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  • 2021-09-07关于多相式睡眠 科学家到底知道什么?[ ♪ Intro ][片头音乐] Conventional wisdom says we’re supposed to get 8 hours of sleep a night.人们普遍认为 我们晚上的睡眠时间 应该达到8个小时 Fewer of us actually do,事实上能做到的人特别少 with the CDC reporting that a third of American adults snooze for less than 7.美国疾病控制与预防中心公布 三分之一的美国成年人 睡眠时间达不到7个小时 Now, the current consensus from sleep researchers is目前 睡眠研究者们的普遍共识是 that we need to sleep for long enough, continuously enough, and deeply enough我们需求足够长久 连续 深沉的睡眠 to receive the proper benefits of sleep.以便 能够获得相当的睡眠好处 And that’s a long list of benefits…睡眠好处可以列成一张长长的清单 like top cognitive performance, proper storage of memories,比如 很好的认知能力 正确的记忆储存 or avoiding health problems like high blood pressure and obesity.或者 防止诸如高血压 肥胖症之类的健康问题 We need sleep.我们需要睡眠 But some people try to break their sleep into chunks不过 有部分人设法将他们的睡眠分成几个时间段 instead of getting a single — or monophasic — stretch of Zs.而不是 保持单个的 或者说单相式的 睡眠时间段 Despite the trends,这种睡法尽管流行 there’s not much scientific evidence to suggest但是 并没太多科学证据表明 polyphasic sleep is better than monophasic.多相式睡眠比单相式睡眠更好 And some polyphasic sleep patterns are distinctly worse.而且 某些多相式的睡眠方式 明显更加糟糕 We don’t fully understand how sleep works.我们并没有完全弄懂 睡眠是如何运作的 The leading model for why and when you sleep关于你为什么和在什么时候睡觉 最重要的模型 is called the two-process model.被称为 双进程模型 It states that there are two, well, processes going on in your brain它表示 在你的大脑里 发生着这样两种进程 that dictate how sleepy you are at any given time.这两种进程决定着 你在任何特定的时间下 会感觉到有多困 One, called process C,其中一个 被称为C进程 is a product of your circadian rhythm,它是昼夜节律的产物 or the attunement of your brain to the cycle of day and night.或者说 是大脑对昼夜循环适应的产物 Your biological clock is run out of your brain’s anterior hypothalamus.你的生物钟受到下丘脑前部的控制 It ticks along in response to light,生物钟的运作受到阳光的影响 and makes you sleepier at night.它让你在晚上会觉得更困 The other, called process S,另外一个 被称为S进程 is homeostatic,它是内环境稳态的进程 which is to say换句话说 it reflects the need for your body to maintain a steady state in all things.它反映了 你身体需要让一切维持在一个稳定的状态中 We don’t know what exactly regulates process S,我们不知道 究竟是什么控制着S进程 but it may have to do with the buildup and clearing out of chemicals like adenosine in your brain.不过 它可能与大脑中化学物质 比如腺苷的累积和消耗有关系 The longer you’re awake,你醒着的时间越长 the more sleepy process S makes you.S进程就会让你觉得越困 And the longer you’re asleep,而你睡眠的时间越长 the more likely it is to wake you up.S进程就会更加有可能使你醒来 While scientists are still revising the two-process model,尽管 科学家们还在修正双进程模型 those basic parts do seem to explain不过 模型的基本框架 好像确能解释 why we sleep for a long time at night.为什么我们在晚上会睡上很长的时间 Process S and process C can change as you get older,随着你年龄的增长 S进程和C进程能够产生变化 and they operate independently from one another.并且 两种进程彼此独立运作 So it’s possible to separate your sleeping patterns因此 这有可能让你的睡眠模式 from the pattern of sunrise and sunset.不再遵循日出日落的模式 And scientists use this fact科学家们利用这个事实 to study sleep by placing subjects on an altered schedule.通过改变实验对象作息安排的方式来研究睡眠 In one oft-cited 1992 study published in the Journal of Sleep Research,在一项经常被引用的 1992年发表于《睡眠研究》期刊的研究中 7 participants were placed on a schedule7名实验参与者的作息计划 被安排为 with 10 hours of light and 14 hours of darkness.光照时间10个小时 无光照时间14个小时 Over the course of several weeks, they eventually took to他们经过几周的时间 最终养成这样的睡眠习惯 sleeping in two blocks during the dark period,他们在无光照的时候 分成两个时间段进行睡眠 with a few hours awake in between.而两段之间则会有几个小时的清醒时间 This, combined with historical knowledge, is sometimes used to suggest这个实验 结合历史知识 有时会被用来表明 that humans naturally adopted a biphasic sleeping pattern人类在拥有使自己熬夜的电灯之前的时代 in the days before we had electric lights to keep us up.会本能地采用两段式的睡眠方式 The idea of breaking up sleep into a polyphasic pattern, though,不过 采用多相式睡眠方式的想法 has been taken to some extremes.已经走向了某种极端 The scientist Buckminster Fuller somewhat infamously subscribed to the Dymaxion sleep schedule,科学家巴克敏斯特·富勒因为提出了 Dymaxion睡眠计划 而有些名声狼藉 which involves 4 30-minute naps evenly spaced throughout a 24-hour period.这种睡眠计划是 在24小时里间隔相同时间进行4次30分钟的睡眠 Some swear by similarly draconian napping schedules, like the Uberman,有一些人对类似的严酷睡眠计划推崇备至 比如Uberman式的睡眠计划 totaling only a couple hours of sleep per day.这种睡眠计划 每天总共也只有两个小时的睡眠时间 While others recommend longer “core” rests at night.然而 另一些人则建议晚上应该有更长的“核心”睡眠时间 Napping in the afternoon, or taking a siesta,中午打盹 或者说午睡 is technically a polyphasic sleep schedule,严格说来 就是多相式睡眠计划 and it’s followed in many parts of the world.世界很多地方都在采用 Breaking up your rests could work by affecting process S,多相式睡眠产生作用的方式 可能就是影响大脑的S进程 basically resetting the make-you-sleepier ticker more often.大致来讲就是 更加频繁地重新设置“让你更想睡觉”的时钟 However, polyphasic sleep isn’t well studied.不过 对多相式睡眠的研究并不完善 When it is, it’s in the context of shift work,多相式睡眠 总是出现在轮班制的工作环境中 like of people providing essential services in hospitals and fire stations.比如 在医院和消防站的轮班制工作中 A 2014 study in the journal Chronobiology International《国际时间生物学》2014年发表的一篇研究 argued that 12-hour shifts probably aren’t great for productivity.论证了 12小时轮班制很有可能对生产效率没有好处 After 12 hours of work,在工作12小时后 people may suffer from decreased alertness,人们警觉程度可能会降低 especially at night尤其在晚上 when their circadian rhythm is making them naturally sleepy. Instead,晚上昼夜节律会让他们自然而然地犯困 the researchers proposed shorter schedules,研究者们反而建议 更加短暂的作息安排 like 6 hours on and 6 hours off,比如 工作6小时 休息6小时 or 4 hours on and 8 hours off.或者 工作4小时 休息8小时 In the experiments they ran,在他们进行的实验里 29 participants were put on29名实验参与者的作息计划 被安排为 a 28-hour schedule with at least 9 hours of time in bed.总时长28小时 其中睡眠时间至少达到9小时 Half were on a conventional light-dark schedule其中一半参与者 采用传统昼夜式的作息安排 and half were broken up,而另一半 则采用多相式的作息安排 with periods of 4.6 hours of rest and 9.3 hours awake.睡眠时间4.6小时 清醒时间9.3小时 The two groups didn’t differ in their performance在警觉程度和反应时间的测验中 on a test that measured their alertness and reaction times这两组参与者的表现并没有区别 — even though participants on the split schedule尽管 采用多相式作息安排的参与者 sometimes reported feeling less alert.有时候会报告说感觉警觉程度在降低 And this led the authors to suggest这让实验制定者们认为 that shorter work shifts with shorter rest periods工作轮班时间短些 同时休息时间短些 could help shift workers.这对轮班制的工人 是有帮助的 However, it’s important to note the不过 重点要指出的是 participants still got in这些实验参与者的睡眠时间 a solid one third of their “ day ” as rest.还是整整占到了他们“一天”时间的三分之一 Less than that and you enter the realm of sleep deprivation,你睡眠时间少于三分之一 就会进入睡眠缺乏状态 which comes with a list of symptoms同时会伴随有很多症状 like anxiety, irritability, poor reaction times,比如 焦虑 易怒 迟钝 and longer-term health risks like high blood pressure and diabetes.以及 诸如高血压 糖尿病之类的健康危险 Some early sleep research failed to某些早期的睡眠实验表明 show any ill effects实验参与者每天睡眠时间只有4或5个小时 when participants slept for only 4 or 5 hours a day.而并没有产生任何负面的影响 But now, researchers think those experiments were poorly controlled.不过现在 研究者们认为 这些实验缺乏有效的控制 And more recent studies show最近更多的研究表明 drop-offs in cognitive function when less than 7 hours are spent in bed.睡眠时间没有达到7个小时 认知功能就会降低 Even worse, you may not know how exhausted you are.更糟糕的是 你可能并不知道 你到底有多疲倦 Some studies, including one from the journal Sleep in 2003,一些研究 其中包括2003年《睡眠》期刊上的一项研究 have found a disconnect between self-reported sleepiness and objective sleepiness利用脑电图通过对脑电波活动的检测 as measured by electrical activity in the brain, with EEG.已经发现了 主观上的困意和客观上的困意 是彼此分开的 Sleep-deprived people tended to think they睡眠缺乏者往往认为 were way better off than their scores on cognitive tests actually indicated.比起认知测试中真正得到分数 自己的认知状态要好上很多 And while it might be okay to break up your sleep a little,尽管 睡眠时间稍微分隔一下 是没问题的 researchers have also studied sleep fragmentation不过 研究者们还是对碎片化睡眠开展了研究 — when you wake up too many times during your rest period.碎片化睡眠 指的是 睡觉时醒来次数过多的睡眠 For instance, many researchers think比如 很多研究者认为 that uninterrupted sleep is necessary to store memories properly.对正确的记忆存储而言 不间断的睡眠是必须的 A study published in 2012 in the journal PLoS One found一项在2012年发表于《PLoS One》期刊上的研究 that subjects whose sleep was interrupted during a monophasic rest pattern发现了 在采用多相式睡眠方式期间 间断睡眠的实验对象 had an impaired ability to form memories.记忆形成功能方面 会受到损伤 So while we don’t understand everything yet,那么 尽管我们还没有弄清楚所有的事情 it’s clear that we need sleep to be our best selves.但我们清楚的是 我们需要睡眠来成就最好的自我 And our brains definitely need more than two hours.而且 我们大脑肯定需要超过2个小时的睡眠时间 You can try to reprogram it if you want to,如果你想要 你可以尝试对大脑重新编程 but it’s at your own risk.不过 风险自负 Thanks for watching this episode of SciShow!谢谢收看本期《心理科学秀》 If you want to learn more如果你想了解更多 about some groundbreaking discoveries biologists have made about sleep,生物学家们对于睡眠领域的突破性发现 check out our list show all about it!请收看我们所有关于睡眠的节目吧 And if you just want to keep getting smarter with us,你要是想要和我们一起不断变得更加聪明 you can go to youtube.com/scishow请登录网址youtube.com/scishow and subscribe.订阅我们吧 [ ♪ Outro ][片尾音乐]
  • 2021-09-07机器人外科医生和其他4项如科幻小说的医学进展《科学秀》 Modern medicine is pretty incredible.现代医学成就让人叹为观止 But even in a world where open-heart surgery但即便在心脏直视手术 and brain-scanning headsets sound almost mundane,和耳机式脑扫描仪都很寻常的当今世界 some medical advances do truly一些医学进展确实 seem like science fiction.看起来像科幻小说一样 So here are five recent developments下面五项近期医学进展 that sound like they’re straight out of the future,尽管听起来像是来自未来 but are already around today.但如今已成为现实 Robots and surgeons go way back—机器人外科医生很早就有 in fact, robots have been in operating rooms实际上 机器人在手术室中应用 since the late 1980s,开始于20世纪80年代末 helping out with all types of routine procedures.用于辅助完成各种常规的工作 But in February 2020,但是 2020年2月 surgeons in the Netherlands kicked things up a notch.荷兰外科医生提高了机器人应用水平 They used a very precise robotic arm他们使用了非常精确的 with teeny tiny tools on the end末端带有微型工具的机械臂 to operate on blood vessels just a few times the size of a human hair.能在只有几倍头发直径的血管内进行操作 It was the first human trial这是人类进行的首次 of robot-assisted supermicrosurgery,机器人辅助超显微外科手术试验 which is surgery on vessels smaller than eight-tenths of a millimeter.手术是在小于8/10毫米的血管内进行的 Surgeries at these scales are really tricky for humans,这样微观级别的手术对人类是很困难的 because our hands do shake— maybe just a little bit,因为人手难免会抖动 哪怕幅度很小 but at these scales, every millimeter counts.但在这个级别一毫米都很重要 So only highly-trained surgeons所以只有训练有素的外科医生 are capable of doing these procedures.才能够完成这类手术 One of these very precise surgeries,此类精确手术的其中一种 called a lymphatico-venous anastomosis, or an LVA,被称为淋巴静脉吻合术 或LVA is a treatment for breast cancer patients它是针对淋巴液不能正常回流的 whose lymph isn’t draining properly.乳腺癌患者的一种治疗方法 Lymph is a fluid that transports white blood cells淋巴液是一种在体内输送白细胞 and other nutrients around the body—和其它营养物质的液体 and when it doesn’t drain properly,如果不能正常回流 it can cause swelling and pain.会引起肿胀和疼痛 But with surgery, tiny lymph vessels can be connected to blood vessels但通过手术将小淋巴管与血管相连 to give the lymph another way out.给了淋巴液另一个引流途径 This surgery is at the very limit of human capabilities,这项手术几乎超出了人类能力的极限 but the team of surgeons and roboticists in the Netherland但是荷兰的外科医生和机器人团队 thought they might just be able to认为他们也许能够 make the procedure easier and safer.让手术变得更容易 更安全 They devised a robot called MUSA,他们设计了一款名叫MUSA的机器人 which mimics a surgeon.完全模仿外科医生 It has two arms that go over the patient,它用两条机械臂给病人实施精细操作 with tiny surgical tools on the ends instead of hands.其末端的微型手术工具可代替人的双手 To manipulate the robot,为了操控机器人 a surgeon looks at the patient through a microscope外科医生通过显微镜观察病人身体 and moves a set of controllers并操作一组控制器 as if they were operating directly on a person.就像直接在病人身上操作一样 But it’s the robot’s tiny tools that are actually performing the surgery.但实际上是机器人的微形工具在完成手术 The robot mimics the surgeon’s movements exactly,机器人可以精确地模拟外科医生的动作 except it filters out tremors.只是滤除了抖动 It also scales those movements down,机器人也缩小了动作幅度 since the surgeon is looking at the patient through a microscope因为医生在用显微镜观察患者 and making bigger motions.手上动作幅度较大 Out of 20 surgeries, MUSA assisted in eight,MUSA协助了20例手术中的8例 and all of them were a success.都获得了成功 Unlike a human, the robot didn’t twitch or get tired,与人类不同 机器人不会痉挛或疲劳 and it could hold an awkward position forever if it had to.需要的话它可以永远保持一个别扭的姿势 This success is really exciting,这次成功很令人鼓舞 because a robot like MUSA could因为MUSA这类机器人 make this type of complex surgery possible for more surgeons—能够帮更多外科医生进行此类的复杂手术 which means more people could get the treatment they need.这意味着更多人可以获得所需的手术治疗 The reason a lot of people who are paralyzed can’t move their limbs许多瘫痪的人无法移动四肢是因为 is because the nerves that should be taking signals本应在大脑与其他身体部位间 from the brain to the rest of the body传递信号的神经组织 aren’t working the way they should.没有正常工作 And for many people with this kind of nerve damage,对许多此类神经损伤患者 the condition is permanent.这种病是终身的 But in a case study published in 2019 in the journal但在2019年《柳叶刀神经病学》 期刊的 The Lancet Neurology,一项病例研究中 a team of researchers in France found a creative way一个法国研究团队发现了一个开创性方法 for a man who was paralyzed below the neck可以让一个脖子以下瘫痪的男子 to control his limbs again.再次控制自己的四肢 Their idea was to bypass the nerves completely—他们的方案是完全绕开神经 by recording messages straight from the brain直接记录来自大脑的消息指令 and sending them to a machine that could carry out its orders.并将其发送给能执行指令的机器 The solution combined incredible advances方案结合了两项不可思议的先进科技 in both brain scanning and robotics.脑扫描和机器人技术 First, the team inserted two small implants into the patient’s brain首先研究团队将两个小装置植入患者大脑 to measure activity in the areas that control movement.以检测运动控制区域的大脑活动 The implants were hooked up wirelessly to a computer system,植入装置以无线方式连接到计算机系统 which decoded the brain signals对大脑信号进行解码 and translated them into instructions将其转换为控制虚拟化身 for a virtual avatar or a full-body exosuit.或全身机械装置的指令 But it was not as straightforward as it sounds.但这并不像听起来那样简单 See, scientists know which regions科学家知道大脑的哪些区域 of the brain broadly control movement,在大体控制人的运动 but for this contraption to work,但是要使这些装置起作用 the system needed to match up an exact pattern of active brain cells该系统需要将确切的脑细胞活跃模式 with a specific movement.与特定的运动相匹配 And that’s not exactly easy.而这并不容易 Like, what does [this] look like on a brain scan, compared to, like, [this]?“这样”和“这样”时 脑扫描有什么区别呢? The team started by having the patient think about a specific action —该团队先让患者思考一个特定的动作 like rotating his wrist or moving a wheelchair forward.比如旋转手腕或向前移动轮椅 The computer—which was hooked up wirelessly to his brain—无线连接到患者大脑的计算机 would record the signals that thought created.会记录思考时产生的大脑信号 Then, over the course of two years,这样 在两年的时间里 the computer created a model of the patient’s brain—计算机创建了一个患者大脑活动的模型 basically like a dictionary that matched brain patterns to movements.就像是将脑的活动模式与特定运动相匹配的字典 In a way, he was both training the computer一方面 患者要训练计算机 to understand his brain signals,理解他的大脑信号 and training himself to think in a structured and focused way同时训练自己有条理地 专注地思考 that a computer would understand.以便于计算机理解 And in the end, the patient was able to use the system最终 患者能够使用该系统 to do all sorts of things!执行各种操作 He drove a wheelchair and made virtual hands do things可以开动轮椅 让虚拟手臂做诸如 like turn over or touch a target.翻转或触摸目标的动作 He also gained the ability to start and stop an exoskeleton.患者还有了启动和停止机械外骨骼的能力 It was attached to a harness mounted on the ceiling,外骨骼与装在天花板上的系带相连 so while he wasn’t completely independent,因此虽然患者不是完全独立 he could essentially walk.但他确实可以走路 Now, this wasn’t the first time scientists created an interface这不是科学家们第一次创建 between a brain and a computer,大脑和计算机的接口 but the small surgery it required但这次所需的小手术 was much less invasive than other methods.比其它方法带来的伤害小得多 And while it’s still a long ways from widespread use,尽管该系统离广泛使用还很遥远 it’s a big step toward developing a way for paralyzed people但在为瘫痪人士开发出仅用意念 to control robotic limbs with nothing but their thoughts.就能控制义肢方法的道路上前进了一大步 In March 2020, doctors in Oregon announced that2020年3月 俄勒冈州的医生宣布 they had used the DNA-editing tool CRISPR-Cas9他们首次在活人身上使用了 in a living person for the first time.基因编辑工具CRISPR-Cas9 Their goal was to treat a rare genetic condition that causes blindness他们的目标是通过修复出错的基因编码 by just fixing the faulty code in the DNA.来治疗导致失明的罕见遗传病 Which is actually possible这其实是可能的 because Cas9 is an enzyme that can cut apart molecules,因为Cas9是一种能切开分子链的酶 and it allows researchers to snip a strand of DNA它使研究人员可以在精确的位置 at a precise location把DNA链剪断 and replace faulty code with new instructions.并用新基因编码替换错误的编码 This technology itself isn’t that new.这项技术本身并不是特别新奇 Scientists have been using it to edit genes2013年以来 科学家们一直在用它 in bacteria, fruit flies, plants, and other organisms since 2013.编辑细菌 果蝇 植物和其它生物的基因 And in a different study, also published in February of 2020,2020年2月发表的另一项研究显示 doctors actually edited the white blood cells of three people with cancer—医生实际上编辑了三名癌症患者的白细胞 but they did the editing outside the patients’ bodies.但他们是在患者体外进行编辑的 That same month, though,不过 就在同月 the team in Oregon took gene-editing a step further俄勒冈州团队将基因编辑向前推进了一步 when they announced that they had used it directly in the human body他们宣布已开始使用该技术直接在人体内 to edit the genes of living cells—编辑活细胞的基因 although when we filmed this video,不过我们录制此视频时 they didn’t yet have their results.他们的结果还没有出来 This clinical trial involved a patient该临床试验涉及的患者 with a rare inherited eye disease患有一种罕见的遗传性眼病 called Leber congenital amaurosis,叫作利伯氏先天性黑矇 which affects the cells of the retina and causes blindness.能影响视网膜细胞 并可导致失明 And this disease can be caused by这种疾病可能是由于 a mistake in a gene called CEP290 –CEP290基因的突变而引起的 that’s what researchers wanted to fix.这就是研究人员想要修复的问题 In the trial, doctors used a needle to inject a few drops在试验中 医生用针头将几滴 of a solution containing the CRISPR-Cas9 system含有CRISPR-Cas9系统的溶液 into the space just behind the retina.注入视网膜后方的空间 The idea was that CRISPR-Cas9 would find the cells of the retina医生设想CRISPR-Cas9会找到视网膜细胞 and snip away the mutation,并剪除突变基因 leaving behind a functional gene.留下一个功能正常的基因 If it works, it should be a permanent cure.如果起作用的话 应该能永久性治愈该病 And the retina is a good place to test out gene editing in humans,视网膜是测试人体内基因编辑的好地方 because it’s isolated from the rest of the body—因为它独立于人体其他部位 so changes made on one eye won’t affect any other part of the body.一只眼的变化不会影响身体的其它部位 After all, there are a lot of valid reasons毕竟 在人体内做基因编辑 to be concerned about doing gene-editing in humans—我们是有足够理由感到忧虑的 but this is a pretty safe place to start.但这是一个非常安全的起点 And if the procedure does cure the patient’s blindness,如果该手术确实治愈了患者的失明症 it’s not just good news for people with this rare disease;这不仅对患有该罕见病的人是个好消息 it could open up the possibility for other gene therapy treatments as well.它也许会为其它基因疗法开辟可能性 These days, there’s not much you can do现如今 要是你刮破了膝盖 if you scrape up a knee or get any injury that breaks the skin.或受到任何皮肤损伤 你能做的很有限 It’s just got to heal, and it takes as long as it takes.只能等它愈合 而且需要的时间很长 But in 2018, 但在2018年 researchers at the University of Wisconsin-Madison威斯康星大学麦迪逊分校的研究人员称 reported that they had built a device他们制作的装置 that healed injuries in rats four times能使老鼠伤口的愈合速度 faster than they heal on their own.比其自然愈合速度提高四倍 The device itself is really simple:装置本身非常简单 It’s basically a little electric bracelet其实就是一个小的电子手镯 that delivers gentle electric pulses to the site of an injury.可以向受伤部位传递柔和的电脉冲 Now electricity naturally plays a role in helping wounds heal.电流天然地就有帮助伤口愈合的作用 Scientists have known since the 1800s that从19世纪初期 科学家就己经知道 anytime you get an injury,如果你受伤了 your body naturally creates an electric field around it.你的身体会自然地在伤口周围产生电场 And in more recent studies, researchers have even watched在最近的研究中 研究人员甚至观察到 cells move around and restructure themselves细胞在电场作用下 in response to an electric field.开始移动并自行重组 You know. As they do.研究人员做这些试验时 They still don’t know exactly他们仍不清楚 how the cells are responding to that electricity,细胞对于电流的反应的确切原理 but electricity seems to promote the growth of new cells,但是电流似乎可以促进新细胞的生长 which is what it takes to close a wound.而这恰好是伤口愈合所需要的 So this device was designed to speed up healing因此 该装置的作用是为创伤区域 by providing additional electricity to the injured region.提供额外的电流以加快伤口愈合速度 And in rats, the results were kind of incredible.在老鼠身上试验的结果出人意料的好 An injury that normally took almost two weeks to heal通常几乎要两周才能愈合的伤口 closed up in three days.三天就愈合了 Eventually, researchers hope to最终 研究人员希望 test something like this on human skin.在人类皮肤上测试类似装置 And in the meantime, they’ve found evidence that同时他们发现 有证据表明 this technology may even have an extra perk—该技术甚至可能还有一个意外功效 it might reverse baldness.可能会逆转脱发进程 In a separate experiment,在另一个实验中 they applied a patch with the same technology他们把运用相同技术的贴片 to mice with a genetic condition用到患遗传病的老鼠身上 keeping them from producing certain chemicals that make hair grow.该病会阻止老鼠产生某些促进毛发生长的化学物质 So the mice are naturally hairless,所以这些老鼠天然是没有毛发的 but after just nine days,然而仅仅过了9天 they’d grown hair under the electric patch.老鼠电极贴片下的皮肤长出了毛发 Researchers believe the patch works研究人员认为 这些贴片 by stimulating the cells in the area通过刺激该区域的细胞起作用 so they release those chemicals that tell hair to grow.释放出了促进毛发生长的化学物质 Now, you may have noticed that你可能已经注意到 your head is not mouse skin.你的头皮不同于老鼠皮肤 But if tests in humans go well,但如果人体试验顺利的话 products with this technology could eventually hit the market,采用该技术的产品有望最终推向市场 but in the meantime— in case you need me to say it—但同时 我要提醒大家的是 don’t try this at home.请不要在家中尝试 Everywhere around the world,在世界各地 there are more people who need organs than there are donors.需要器官的人都比捐献者要多 Like, right now, there are over 100,000 people in the U.S. waiting for kidneys.比如目前 美国有超过10万人在等待肾源 And even in a record-setting year like 2019,即使在2019年这一创纪录的年份 fewer than a quarter of those people will get them.也只有不到1/4的人能得到所需肾脏 So lives depend on finding more kidneys.所以 生命的延续有赖于寻找更多的肾脏 And in 2015, doctors in the U.K. found a new way2015年 英国医生发现了一个 to put kidneys from deceased donors back in business,能将死者肾脏恢复正常功能的新方法 using a technique called ex-vivo normothermic perfusion.使用了一种称为体外常温灌注的技术 This technique uses a jolt of nutrients该技术使用了一些营养素 to repair kidneys from deceased donors来修复已故器官捐献者的肾脏 and make them usable again—which is not easy.并使它们可以再次使用 这并不容易 Because, as soon as a person dies, their organs start to deteriorate.因为人一旦死亡 器官状况就开始恶化 Doctors can slow that deterioration by chilling an organ,医生可以通过冷却器官减缓恶化进程 but even then, kidneys have to be transplanted within a day or two,即便如此 肾脏必须在一两天内移植 or they’re often too far gone.否则通常就不能用了 This new procedure helps by putting new life into kidneys这项新技术通过给肾脏注入新的生机 that have passed the usual point of no return.来挽救通常已经过了使用时限的肾脏 First, the kidney gets removed from the deceased donor先像平常一样 将肾脏从捐献者体内取出 and kept cold, just like usual.并保持冷藏状态 Then it has to travel—然后是运送过程 sometimes down the hall, other times to a different city.或运过大厅 或运送到另一个城市 Once it gets where it’s going,一旦到达目的地 it goes into a special machine that’s kind of like a spa肾脏会被放入一台类似水疗的特殊机器 But for kidneys,it pumps warm blood and nutrients它专为肾脏设计 通过器官向肾脏输送 through the organ until it’s working at peak efficiency.温热的血液和营养 直至其达到最强功能 Then it’s good to go back to work in the world of the living.然后欣然回到一个有活力的身体继续工作 What’s cool about this procedure is该技术的优点在于 it doesn’t just wake the kidney back up—它不仅可以唤醒肾脏 it also gives the surgeons a chance to make sure还能让外科医生有机会确认 the kidney works on a machine, before it goes into a human.肾脏在进入人体之前 能先在机器上运作 Kidneys that were borderline become healthy enough处于生死边缘的肾脏在水疗之旅后 to use after this little trip to the kidney spa.就能重获健康 再次应用 And, so far, the early results are promising.目前为止 早期结果比较乐观 Initial studies show that the revived kidneys are at least初始研究表明 机器恢复的肾脏至少 as safe as kidneys typically used for transplants.与通常用于移植的肾脏一样安全 Other trials are still in progress to make sure it’s completely safe,其他试验仍在进行 以确保其绝对安全 but if things go well, this could save a lot of lives.但如果一切顺利 它能挽救很多人的生命 For now, many of these advances are proofs of concept目前 这些进展还处于概念验证阶段 and still far from being your everyday reality,距离我们的日常生活还很遥远 but they show how quickly science fiction can become science但这展示了科幻小说正快速变为科学现实 and help us to live longer, healthier lives.并让我们更加长寿和健康 Thanks for watching this episode of SciShow!感谢收看本期《科学秀》 And a special thanks to our patrons on Patreon特别感谢我们在Patreon上的支持者 who make it possible for us to share让我们得以跟大家分享 all this amazing science with you.这些惊人的科学资讯 If you’d like to join our amazing community of patrons,如果您想加入我们优秀的赞助人团 you can find out more at patreon.com/SciShow.可在patreon.com/SciShow找到更多信息
  • 2021-09-07伪装:动物捉迷藏嘘!我们正在玩捉迷藏!Shh! We’re playing hide and seek! 但是,我似乎不能找到Squeaks.你能吗?But, I can’t seem to find Squeaks. Can you? 轻音乐播放着[Soft music playing] 啊哈!找到了!Hah! Found yah! 咯咯的笑![Giggles] 在这里,我们很擅长捉迷藏。Here at the fort, we’re pretty good at hide and seek. 你知道为什么吗?You know why? 因为我们从大自然中学到了许多很棒的技巧。Because we’ve learned a lot of great tricks from nature! 许多动物都有它们自己的捉迷藏方式。There are lots of kinds of animals that have their own kind of hide and seek — 一些动物藏起来,因此它们能悄悄靠近它们的猎物Some animals hide so they can sneak up on their prey– 其他动物藏起来,因此它们不会成为晚餐other animals hide so they don’t become dinner! 不管怎样,这些动物不会藏在窗帘后面或者桌子下面Either way, these animals don’t hide behind curtains or under tables 像是当我们捉迷藏时做的那样like we do when we want to play hide and seek — 它们躲藏在大自然当中they hide in plain sight! 听起来很不错!That sounds amazing! 它们能这样做多亏了伪装的本事And, they can do it thanks to camouflage. 一个叫做Rianne的SciShow Kids电视观众想要知道One SciShow Kids viewer named Rianne wants to know: 伪装是什么,是怎么工作的?What is camouflage and how does it work? 问题非常好!Great question! 伪装是一些动物迷惑或者躲避其他动物的一种方式Camouflage is a way for animals to confuse, or hide from, other animals. 自从许多不同的动物都在躲藏或者寻觅Since lots of different animals are all either hiding, or seeking, 在大自然中就有了许多不同种类的伪装there are lots of different kinds of camouflage in nature. 对于动物伪装的一个简单方法就是把它们自己混入到背景当中One easy way for an animal to camouflage itself is to just blend in with the background. 比方说你在树林中安静的散步时Let’s say you take a quiet walk in the woods — 你希望看到什么动物?what kind of animals would you expect to see? 好吧,在我住的地方,我可能会看到一些松鼠Well, where I live, I might see some squirrels, 或者是一头鹿,也可能是一只可爱的小田鼠or, a deer, or maybe a cute little field mouse. 你觉得这些哺乳动物们拥有的共同点是什么?And you know what these mammals all have in common? 它们都有棕色或者灰色的渐变色They’re all shades of brown or gray — 它们搭配着它们居住地方的树皮的颜色和森林底色they match the color of tree bark and the forest floor where they live. 这使它们更难被发现This makes them harder to spot. 许多动物混入到它们所处的环境中Lots of animals blend in with their environment, 但是并非所有动物都依赖它们的颜色去伪装but not all of them rely on their color to do it — 一些动物也从它们的皮毛图案中得到帮助some animals get help from the patterns on their skin and fur. 老虎的黑色大条纹使它们在高高的草丛中更难被发现Tigers have big black stripes, which makes them harder to find in tall grass. 在小鹿身上斑点是浅黄褐色的And the spots on baby deer, called fawns, 看起来的图案像是阳光闪烁着look like patterns that sunlight makes as it shines 照射穿过树木和草丛down through trees and grass, 因此当它们想要美美的休息一会时会蜷缩在植被中so when they curl up among some plants for a nice nap, 很好的混入其中they blend right in. 现在,生活在水里的动物们Now, animals that live in the water have a 有一个不同的环境需要去混入different environment that they have to blend into. 许多海洋动物,像是海豚,鲨鱼,和鲸鱼Many ocean animals, like dolphins, sharks, and whales, 通常都是浅灰色,或者蓝色来搭配水的颜色are often light gray, or blue-ish, to match the color of the water. 但是它们也有另外一个技巧,它们胃的颜色要But they have another trick, too, they’re lighter on 比他们背的颜色更浅their stomachs than they are on their back. 看这只鲨鱼,它被叫做灰色暗礁鲨Look at this shark, it’s called a gray reef shark. 如果你在这只鲨鱼上面游泳时,往下看If you were swimming above the shark, looking down, 它的蓝灰色的背会和它身下海水的颜色混为一体its blue-and-gray back would blend in with the waters of the ocean below it. 但是如果你在鲨鱼下面游泳往上看时But if you were swimming under the shark and looking up, 当阳光穿过它时,它的白色的胃会和上面的水的颜色相匹配its white belly would match the lighter water above, as the sun shines through it. 你可能会说这个鲨鱼从头到尾被覆盖了You might say this shark is covered from top to bottom! 一些动物既不依靠颜色也不依靠它们自身的图案And some animals don’t just take on the color or pattern 它们利用它们的形状来伪装of their surroundings — they camouflage themselves using their shape! 看看这个家伙。你能看到吗?Take a look at this guy. Can you see it? 这被叫做行走的树叶!毫无疑问!It’s called the walking leaf! And no wonder! 这个行走的树叶不仅有绿叶的颜色和形状The walking leaf not only has the color and shape of a 他甚至标记他的身体看起来像是被啃咬了一样green leaf, it even has markings on its body that make it look like it’s been nibbled on. 现在,试着找到这条多叶的海龙Now, try to spot this leafy sea dragon. 全身被小鱼鳍覆盖,Covered in small fins all over its body, the leafy sea 多叶海龙完美的融入到他们生活的海草当中。dragon blends perfectly in the seaweed where it lives. 这种多叶海龙甚至像是一片海草一样移动,The leafy sea dragon even moves like a piece of seaweed, 优雅的在水里翻筋头gracefully tumbling around in the water. 这是一种很有说服力的伪装That’s some convincing camouflage! 但是当然,许多动物和他们身处环境中的东西看起来并不完全一样But of course, a lot of animals don’t naturally look like things in their environment. 所以他们中找到一些方法去隐藏自己…像是玩装扮So some of them have found ways to hide themselves by … playing dress up. 装扮过的螃蟹沿着海底漫步,The dresser crab walks along the seafloor, looking for 寻找它们可以穿上的外壳little things that it can wear on its shell– 像是珊瑚,海葵或者海藻。like coral, sea anemones, or seaweed. When it’s all 当他掩盖或者静坐时,这个螃蟹几乎是看不见的!covered up and sitting still, the crab is nearly invisible! 然后还有这种叫做蒙面猎人的昆虫。Then there’s this insect called the masked hunter. 当它们年幼的时候,它们被细毛覆盖。When they’re young, masked hunters are covered in tiny hairs. 当他丢掉身体上面的灰尘时,他会黏在毛发上,When it throws dust on top of its body, it sticks to the hairs, 完全覆盖它。covering it completely. 它像是一个隐形的斗篷!It’s kind of like an invisibility cloak! 所以现在你明白了吧。So there you have it. 动物们利用各种技巧去隐藏它们自己,Animals use all kinds of tricks to keep them hidden, and 每种动物的方法都有稍微的不同。every animal has a slightly different way to do it, 取决于它们是什么,生活在哪里depending on what kind of animal it is, and where it lives. 谢谢和我们一起学习伪装Thanks for learning about camouflage with us! 你有什么想要了解更多的问题吗?Do you have a question about something that you’d like to learn more about? 从父母那里得到帮助。请在下面留下你的评论或者电子邮件kids@thescishow.comGet help from a parent, and leave a comment below or email us at kids@thescishow.com. 让我们下次再见And we’ll see you next time! 音乐播放中[Music playing]
  • 2021-09-07关于猫咪的冷知识What if I told you that there might be a sneaky predator如果我跟你说 在你家里可能有一个 with super powers in your house right now?潜在的 拥有超强能力的捕食者该怎么办呢? If you live with one of these, there is!如果你和其中的一只在一起生活 那就是真有 I’m talking about cats!其实我说的就是猫! And even if you do have a cat of your own,即使你有猫 I bet you don’t know some amazing things那我敢肯定你也不知道 about our little furry friends!我们毛绒绒的小伙伴的神奇事儿 For example!比如! Did you know that all pet cats are actually related to lions,你知道其实所有的宠物猫都和狮子 and other big cats, like tigers,以及其他像老虎 leopards, and jaguars? 豹子和美洲虎这样的大型猫科动物有关吗? Wait…this…is related to this? 等等……小猫咪……和大老虎有关系? Yes it is!是的! All cats, from the biggest lion to the tiniest of house cats,所有的猫科动物 大到狮子小到家猫 evolved from the same small, cat-like creature 都从一种小而像猫的生物进化而来 that lived millions of years ago 它们叫做原猫或“第一只猫” called proailurus or “first cat”.生活在几百万年以前 Then after a long time,在很长一段时间之后 there came to be two major types of cats.猫科动物进化出了两个种类 One kind became the bigger cats, like the lion and the tiger.一种变成了更大的猫科动物 像狮子和老虎 And the other kind became the smaller cats,而另一种变成了更小的猫科动物 which includes the ones we keep as pets today.包括我们现在养的宠物 So…if all big cats and all little cats descended所以…如果所有的大猫小猫 from this same animal from long, long ago都从同一种生物进化而来 that means they’re related那么即使它们之间有差别 even if it is only distantly.但还是有联系的 That’s one big furry family! 那可是一个毛绒绒的大家庭! Now another cool thing about cats?接下来另一件关于猫的很酷的事情 They have excellent hearing!它们的听力很棒 Lots of animals, including dogs, have better hearing than we do.包括狗在内的很多动物都比人的听力好 But cats can hear better than both human and dogs.但是猫的听力比人和狗的更好 Even if your cat just looks like it’s curled up and enjoying a relaxing nap,即使你觉得你的猫看起来喜欢蜷起来睡午觉 extremely aware of its surroundings.但它仍然对周围的一切了解得一清二楚 Their little ears are super-sensitive, 它们的小耳朵非常灵敏 and they’re always listening.并且一直保持听的状态 Your cat can can hear everything that’s going猫可以听到它周围的一切 on around it, from the sound of you从你在楼上任何位置的卧室里 listening to music in your bedroom all the way upstairs,听音乐的声音 to the sound of birds chirping到邻居院子外面 outside in your neighbor’s yard.小鸟叽叽喳喳的声音 In fact, cats can hear things up事实上 猫能听到的声音的距离 to four times further away than you or I can是我们的四倍远! And they can not only hear things而且它们不仅能听到远处的声音 from far away—they can figure out exactly where而且能精确的判断 those far-away sounds are coming from.这些声音从哪来 So if your cat’s snoozing in the basement,所以如果你的猫正在地下室打盹 and you open the kitchen cupboard where you那么当你打开存放它们 keep their favorate treats,最喜欢的零食的橱柜时 they’ll probably come running.它们就会马上跑过来 But if you open another cabinet in a different part但是如果你打开厨房里 of the kitchen, they’ll probably be另一个橱柜 able to tell the difference and just keep snoozing!它们可能会听出区别然后接着打盹 Thousands of years ago,几千年之前 cats needed this super sense of hearing to help them track down food猫需要有极好的听力来帮助他们寻找食物 and to escape predators in the wild. Today,并且在野外逃离捕食者 now that they live among humans 现在既然它们已经和人类生活 who help provide for them人类可以给它们食物 they don’t need it quite as much.它们就不太需要它了 But it’s always good to know但是 当橱门打开时能听到 when that treat cupboard opens!这总是很好的 And lastly, our third cool thing about cats: They rule! Well,最后一件酷事儿:它们的地位至高无上 sort of!在某种程度上是这样 Some ancient cultures—like people who lived一些古老文化—像几千年前 in Egypt thousands of years ago — 生活在埃及的人们—— treated cats like royalty,把猫当做 皇室成员对待 almost as if they were kings and queens!大部分猫像国王和王后一样 Early Egyptians were thought 据说早期的埃及人总是觉得 to have had problems with rats in their homes.自己家里有老鼠 In order to get rid of the rats,为了赶走这些老鼠 they brought in cats to hunt them.人们引进了猫来捕捉 And the people liked the cats so much,人们非常喜欢猫 they supposedly kept them 所以就收养了它们 and treated them extremely well.并对它们非常好 Ancient Egyptians even mummified the animals古埃及人甚至为了来世的旅行 for their journey to the afterlife,就像对待人类统治者一样 just like they did with their human rulers.把猫做成了木乃伊 So sorry, dogs.所以很抱歉 狗狗们 in ancient Egypt at least, 至少在古埃及 cats ran the show.猫更胜一筹 Now the next time you see a cat,下一次你看见猫的时候 you’ll know that you’re looking at 你就知道你在看 a super-cuddly animal with super-hearing一只超可爱并且听力超棒的动物 that was once treated like royalty 那是一只曾经地位至高无上 and is related to lions and tigers!并与狮子老虎同源的动物 And if you’d like us to sniff out所以如果你想了解 more information about cats or anything,更多关于猫的知识 just let us know!就来联系我们! Get help from a grown up让父母帮助你们 and leave a comment down below,在下方评论 or send us an email或者给我们发邮件 kids@thescishow.com.邮箱为kids@thescishow.com Thanks for joining us!感谢加入我们 We’ll see you next time, here at the fort!我们下次再会!
  • 2021-09-07木星,是敌是友?[INTRO ♪][前奏] Jupiter is more than twice as massive as all the other planets in our solar system combined,木星比太阳系中其他所有行星加起来的两倍还要大 and it has a history of throwing that weight around.而且它的质量一直都在向四周散失 In fact, it likely used its gravity to shape the way our solar system looks today.事实上 木星可能凭其质量塑造了太阳系今天的样子 And that’s generally a good thing for us!整体上来说 这对我们是好事 We have a nice stable orbit at a cozy distance from our star,地球与太阳距离适中 公转轨道平稳 and things are usually pretty calm in our planetary neighborhood.周边行星环境相当平静 So, here on Earth, we have a lot to thank Jupiter for…所以 我们地球有很多需要感谢木星的 but it isn’t always the nicest neighbor.但它并非一直是个好邻居 Now and then, it also sends some hazards our way.它也时不时的使地球处于危险中 That makes sharing a solar system with Jupiter … complicated.这使得与木星同处一个太阳系的感情变得复杂了 On a good day, Jupiter’s got our back.好的时候 木星在背后支持我们 When comets from the outermost reaches of the solar system head toward Earth,比如彗星从宇宙深处来到太阳系冲向地球时 Jupiter’s gravity often acts like a shield by chucking them straight into interstellar space.木星的引力像护盾一样 将它们直接抛到星际空间 And we’ve even seen Jupiter take some pretty big hits for us.我们见识过木星帮我们挡掉一些相当严重的撞击 In 1994, fragments of the comet Shoemaker-Levy 9 smashed into Jupiter.1994年 彗星Shoemaker-Levy 9的碎片撞击了木星 As the impact site rotated into the Earth’s view,当撞击点旋转到面向地球时 scientists could see dark scars on the surface of the planet科学家观测到了木星表面上的黑斑 and plumes of debris rising in its atmosphere.还有碎片尘埃漂浮在大气层中 If a comet like this had hit Earth,假如类似的彗星撞击地球 it would have kicked up an enormous cloud of dust that would have blotted out the Sun将会扬起巨大的尘埃云 遮蔽阳光 and caused mass extinctions on par with the ones that took out the dinosaurs.造成地球生物大灭绝 规模与恐龙灭绝那次不相上下 So not only does Jupiter routinely protect us from comets like Shoemaker-Levy 9,所以木星不仅日常保护地球不受类似Shoemaker-Levy 9彗星的撞击 but that dramatic collision gave astronomers a wake-up call它被撞击也给天文学家提了个醒 —if it happened to our neighbor, it could also happen to us.能发生在邻星上 那也能发生在地球上 Just four years later, in 1998,就在四年后的1998年 NASA got serious about tracking near-Earth objects, or NEOs,NASA开始重视追踪近地天体 简称NEOs that could have catastrophic effects if they hit our planet.指撞击后会导致地球灾难性后果的天体 And now NASA estimates that we’ve found almost all of the thousand or so NEOsNASA目前估算已找到近千个 big enough to cause apocalyptic worldwide destruction.几乎所有大到能导致地球末日的NEOs There are, of course, still plenty of smaller ones that could potentially do some serious damage,虽然仍有许多可能造成严重破坏的较小近地天体 but thanks to Jupiter’s wake-up call in the ’90s,但还是要感谢木星在90年代的提醒 we have a pretty good handle on the scariest threats.让我们对其中最具威胁的彗星做好了应对措施 So, Jupiter deflects some dangerous comets木星使一些彗星偏离方向 and reminds us to keep a lookout for incoming asteroids,并提醒我们注意将到来的小行星 but the biggest planet in the neighborhood doesn’t always play nice.但这个最大的行星邻居并不总是那么友好 For example, in 1770, the comet Lexell flew past it,比如1770年 彗星Lexell掠过木星时 and Jupiter’s huge gravity directed the comet right at Earth.其巨大引力使该彗星直冲地球 It came within 2.3 million kilometers of us!最近时离我们只有230万千米 That’s how far Earth travels in just 21 hours.相当于地球公转21小时的距离 So we dodged it by less than a day!所以我们躲开它时只剩不到一天 And research suggests that this type of event—而且研究表明 类似事件像 where Jupiter throws things into the inner solar system rather than sending them out木星吸引小行星到太阳系内部而不是将其抛向外太空 —might be happening more often than we thought.发生频率可能比我们想象的更多 Like, one simulation of 30,000 space objects比如一个包含3万个天体的模拟 showed that Jupiter might even be teaming up with Saturn显示木星甚至可能与土星协作 to send threatening space rocks our way.将颇具威胁的太空岩石抛向地球 In the model, each simulated object began in a non-threatening orbit somewhere in the outer solar system.模拟开始时 每个天体运行轨道在外太空某个地方 But by the end of the simulation, 8% of those objects were crossing paths with Earth.而到最后 有8%的轨道会与地球相交 And while Jupiter’s gravity was the real culprit slinging objects inward,虽然是木星将它们吸引到太阳系 堪称罪魁祸首 Saturn was guiding objects toward Jupiter.但是土星将它们引向木星 也“功”不可没 In the real world, a good deal of Jupiter’s ammo is likely made up of objects called Centaurs.现实中 木星的“弹药”可能大部分由半人马小行星构成 They’re named after the mythical creature that’s half-person, half-horse,它们的名字来源于半人半马的神话动物 and Centaurs are like hybrids between asteroids and comets:而它们也像是小行星和彗星的“混血” They can have the same make-up as asteroids,它们与小行星组成成分相同 but many of them have comet-like properties like tails of debris.同时很多还有彗星的特征 比如彗尾 For the most part, Centaurs stick to the outermost solar system.大多时候 半人马小行星呆在外太空 But if they get close enough to Jupiter,但一旦它们离木星足够近 the planet’s gravity can alter their path木星的引力就能改变它们的轨道 and throw them into the inner solar system,把它们吸引到太阳系 potentially on a collision course with Earth.并可能与地球发生激烈碰撞 Even when it’s not hurling Centaurs our way,就算木星没有把它们投向地球 Jupiter may make ordinary comets more of a threat than they already are.它也能使本具威胁的彗星变本加厉 Although it throws some of them out of the solar system altogether,尽管木星把一些彗星清出了太阳系 in other cases, a run-in with Jupiter can tighten a comet’s orbit.但其他时候 木星的干扰会缩短彗星的轨道 That means it’ll go around the Sun faster,意味着彗星将加速环绕太阳运行 giving it more chances to hit Earth.增加撞击地球的可能性 In fact, that’s exactly what happened with the famous Comet Hale-Bopp.事实上 这正是著名的海尔波普彗星发生的事情 It last swung by the Sun in 1997,它最近一次掠过近日点是在1997年 and that was the first time it was visible in 4,000 years.这是它4000年来第一次被观测到 But around the same time, an encounter with Jupiter cut its orbital period almost in half,就在那时 木星的干扰使其公转周期缩短将近一半 meaning it’ll come by again in just over 2,000 years!意味着它最快将于二千多年后回归 And just to keep us on our toes, Jupiter’s gravity can also pluck rocks from the Asteroid Belt需要警惕的是 木星引力可以将岩石从小行星带剥离 and send them our way too—which isn’t very neighborly!朝地球扔来 这不是好邻居该做的 But even if we have to give Jupiter a little side-eye now and then,不过尽管我们不得不经常对木星侧目 it could have helped make life on Earth possible.它有可能帮助了地球生物出现 During the formation of the solar system, 太阳系形成之初 its enormous gravity likely helped carve space for our planet to form in the first place.首先 木星巨大的引力可能为地球的形成创造了空间 And even when Jupiter seemed like our enemy,尽管木星看起来像敌人 the space debris it sent our way during Earth’s early years地球形成初期 木星送过来的太空碎片 may also have delivered organic material that helped life form.可能含有机物 帮助孕育生命 So thanks, Jupiter, for helping to get us going early on!所以 谢谢你木星 帮助我们早期出现 You can stop sending us all those asteroids and comets, though.不过 你可以停止向我们扔小行星和彗星了 Beyond helping us learn how to defend our own planet, 除了帮助我们学习如何保卫地球之外 understanding Jupiter’s role in our solar system could help us search for life beyond it.弄清木星在太阳系中的职能可以帮助我们搜寻太阳系外的生命 When we look for habitable worlds orbiting other stars,在我们寻找围绕其他恒星公转的宜居行星时 it might be useful not just to look for Earth-like planets, 不要只关注类地行星 but also to see what a Jupiter-like frenemy might be up to nearby.也看看附近亦敌亦友的类木行星会比较好 Thanks for watching this episode of SciShow Space!感谢观看本期《太空科学秀》 If you want to learn more about how Jupiter tosses its weight around in the solar system,如何你想知道更多关于木星如何在太阳系“减重” you might like our video about the group of asteroids Jupiter has held prisoner你可能会喜欢我们的视频 木星“囚禁”的小行星群 —possibly for billions of years!可能已经“囚禁”了几十亿年 You can find out more about Jupiter’s Trojan asteroids after this.之后你可以了解更多关于木星的特洛伊小行星介绍 [OUTRO ♪][结束曲]
  • 2021-09-07为什么船会浮在水面上?大家好!嘿,Squid在这儿啊!一切还好吗?Hey guys! Hey there, Squid! How’s it going? 唔唔唔,我现在有那么点异常情况。TGS: Mmmph. I’m kinda cranky right now. 噢,不。没有人想那样。是什么在困惑着你?Jessi: Oh no. No one wants that. What’s bothering you? 巡航舰TGS: Cruise ships. 巡航舰?Jessi: Cruise ships? 是的,巡航舰。你知道的,人们会用来到处航行的那些巨型的舰船。TGS: Yeah, cruise ships. You know, those giant boats that you people sail around in. There’s 他们整天在我上面开来开去,我根本没法睡觉。been one floating above me all day, and I can’t get any sleep! 我是说,他们非常大!而且特别吵闹!就像是一个漂浮的城市!I mean, it’s huge! And noisy! It’s like a floating city! 所以,我没有睡觉,只是醒着,四周游荡,瞪着巡航舰,想着为什么。So, instead of sleeping, I’ve just been bobbing awake, staring at it, and wondering. 这么巨大的一艘船是怎样在水上漂浮的呢?How does a giant ship like that float on the water? 我是说,通常情况下重的东西会沉到水底,是这样吧?就像有人扔石子I mean, heavy things sink in water, right? Like when someone up there tosses a rock into 到海里——你知道的,有时候会发生这种事——然后石子会沉入水底。the ocean — which happens, you know — it sinks. 所以说为什么那么重的船能浮起来呢?So why does that heavy ship get to float? 又大又重的船能浮起来和它的形状有关。Jessi: The reason a big, heavy ship like that can float has to do with its shape. 物体的是沉下去还是浮起来有很大一部分影响是来自于Whether an object sinks or floats to begin with has a lot to do with something called 排水量。displacement. 排水量指的是物体在水中排出或移开了多少水。所以说,当你Displacement is when an object displaces, or pushes aside, water. So, like, when you 把冰块放进一杯装满水的玻璃杯里面,会有一些水溢出来。drop an ice cube into an already-full glass of water, some water spills out. 那就是排水量吗?TGS: That’s displacement? 是的——溢出的水的量与Jessi: That’s right — the amount of water that spills out is actually equal to the amount 冰块占据的体积是相等的!of space the ice cube takes up! 或者想想你洗澡的时候。Or think about when you take a bath. 停一下。等等。洗澡是什么?TGS: Hold up. Wait. What’s a bath? 事实上,在陆地上,我们喜欢把自己浸湿在一大盆温暖的水里来清洁身体,Jessi: Well, up here, we like to clean ourselves up by soaking in a tub full of nice warm, 用上肥皂。soapy water. 听上去好粗野!那是不是说你们人类就是每天都要到处走弄得脏兮兮的?TGS: That sounds gross! Do that mean that humans just walk around all day getting dirty? 如果你们都能想我一样所有时间都在水里度过,你就不会弄脏,If you spent all of your time in the water like me, you’d never get dirty in the first 最开始就不会。place. 又不是每个人都是相同的,对吧?我知道肯定有一些在看视频的人知道Jessi: Well, not everyone’s the same, right? I know some of the people watching here know 洗澡是什么的。what a bath is. 好吧好吧。TGS: Mmmrph, okay. 所以,比如说你把浴缸加满水-加到最满。然后你跳进浴缸。Jessi: So, say you fill the bathtub up — all the way to the top. And then you climb in. 现在有水在地板上,很多水。水的体积Now there’s water on the floor. Lots of water. The amount of water equal to the amount 等同于你所占据的空间的体积of space that you took up! 一个物体之所以能飘浮的秘密在于,它必须置换足够的水Now, one of the secrets to an object being able to float, is that it has to displace 以便水能尽量的将它托起enough water so that the water it pushes aside weighs as much as it does. 好的,你在桶里,你想做个实验,你可以Alright, so, say you’re in the tub and you want to do an experiment. You can bring in 带一个小碗,一些岩石收藏品里的石头。a small bowl, and some rocks from your rock collection. 如果你把碗放入水中,它将浮起来,因为碗的底部置换了If you put the bowl in the water, it’ll float. Because the bottom of the bowl is displacing 一些水。水的体积和将碗托起的体积是一样的some water. And the amount of water that it’s pushing aside weighs the same as the bowl. 现在,我们将一个小石头放进去碗里Now, drop a little rock in there. 放进一个,再加一个Add another, and another. 碗变得越来越重了,所以每次都有点往下沉The bowl is getting heavier, so it’s sinking a little bit each time. 但即使碗越来越重,它同时也置换了更多的水But even though the bowl is heavier, it’s also displacing more water — so the amount 水的体积和将碗托起的体积是相同的of water that it’s pushing aside still weighs the same as the bowl. 那么巡航舰怎么解释?它为什么没有沉下去?TGS: So what does that mean for the cruise ship? Why doesn’t it sink? 嗯,轮船被设计得能排开尽可能多的水Jessi: Well, ships are designed to displace as much water as possible. 它们非常非常宽,并且它们的底部延伸得非常远,所以它们推开They’re realllly wide, and their bottoms tend stretch down really far, so they push 大量的水aside a lot of water. 另外,一艘轮船在它的内部有着很大的空间–它的很多地方是中空的–这帮助Plus, a ship has lots of empty space inside it — a lot of it is hollow — which helps 它保持轻,以及与被它所置换的、总量巨大的水比较to keep it light, compared to the huge amount of water that it’s displacing. 瞧…它浮起来了And voila… it floats. 好吧,好吧。所以现在在我头上那么大而且吵闹的聚会正在排出足够TGS: OK, OK. So that giant, noisy party over my head right now is displacing enough water 能使它浮起来的水that it can float. 噢,你们人类可能就是吵闹的,但是你们能够想出怎样建造能够漂浮巨大的金属东西Well, you people may be noisy, but the fact that you figured out how to build giant metal 的事实……非常聪明。我会给你们那个评价things that float… that’s pretty clever, I’ll give you that. 对,我并不了解你,但是我喜爱的一些东西往往是聪明Jessi: Yeah, and I don’t know about you, but some of my favorite things tend to clever 并且吵闹的。谢谢加入乌贼和我,学习排水量。下次and noisy. Thanks for joining Squid and me, learning about displacement. See you next 见time! 旅途愉快TGS: Bon voyage!
  • 2021-09-07垃圾食品是如何干扰你的大脑的[音乐][INTRO ♪] 众所周知 垃圾食品 虽然它不健康 但是 很好吃Junk food: you know it’s not healthy, butit’s so good. 有时候 很难拒绝它And sometimes, it’s just too hard to resist. 科学家曾经试图弄清楚为什么垃圾食品And scientists have been trying to figureout why junk foods 能够如此风靡一时have so much power over us for a while. 根据《细胞代谢》杂志昨天刊登的一篇研究According to a study published yesterdayin the journal Cell Metabolism, 这可能与it probably has a lot to do with the fact that 垃圾食品大都包含脂肪和碳水化合物 有关they’re usually packed with both fat and carbs. Pff, 我的最爱my favorite! 研究者发现当脂肪和碳水化合物这两种营养素混合在一起时The researchers found that the reward centersof our brains 大脑的奖励中心的活跃度are more active when those nutrients are combinedin a snack— 大大超出你的期待above and beyond what you would expect 如果你只添加脂肪和碳水化合物if you just added the fat and the carbs together. 这就是为什么奶昔 薯条Which is why milkshakes, and french fries, 薯条蘸奶昔会如此诱人and dipping your french fries into milkshakes. 这就意味着And that means that it ’ s not 垃圾食品基本上干扰了大脑 现在just you—junk food basically hacks our brains. Now, 有一些现象可以显示there have been hints to this phenomenon forsome time. Mice, 比如for example, 如果只给老鼠吃碳水化合物或脂肪 老鼠就会显瘦can stay trim if they ’ re given either carbs or fat to eat, 但是如果老鼠吃了碳水化合物和脂肪的混合物的话but they pack on the pounds 老鼠整体重量就会增加if they ’ re given a mix of the two. 但很难弄清楚对大脑的影响But it was less clear how that plays out 或者说 对人的影响in the brain, or how it applies to people. 所以德国和美国的神经病学家和生理学家So neurologists and physiologists in Germanyand the US 建立了一种set up a kind 参与者对零食竞标的食物拍卖of food auction where participants bid for snacks 同时 功能磁共振成像检测参与者脑中的活动while the activity in their brains was measuredwith fMRI. 各种零食中的卡路里大多来自碳水化合物The calories in the various snacks were eithermostly from carbs, 脂肪 碳水化合物和脂肪的混合物mostly from fat, or from a mix of both. 食品按大小分类 每一个种类都包含And the items were sized so that each categorycontained 同样数量的卡路里 从能量方面来讲 所有东西都平等对待the same number of calories, to make them equal from an energetic perspective. 实验小组也尽力确保The team also made sure 所有的食物都是在上一次实验中我们所熟知的和喜爱的that all the foods were similarly well known and liked in a previous experiment. 这样 就会不偏不倚That way, the group couldn ’ t prize any set of foods over the others. 但是 参与者们都在套餐提高标价But the participants consistently put higherbids on the combo foods— 比如 巧克力曲奇饼干 方块糖things like chocolate chip cookies and candy bars— 而不是 像 坚果 奶酪 咸饼干这样的食物rather than things like nuts, cheese, or crackers. 目的是为了提供更多This willingness to shell out more 与包含脂肪和碳水化合物的食物相关的for the foods that had both fat and carbs 大脑区域的反射was associated with more of a response inbrain regions 或奖励 终脑皮层的顶部associated with reward, like the top partof the striatum. 研究者怀疑这也许是因为The researchers suspect this may be becausewe have 脂肪和碳水化合物的不同奖励方式separate reward pathways for fats and carbs, 结合物食物同时表现有不同奖励方式both of which are simultaneously turned onby the combo foods. 研究者认为这 就像是 同时奖励电路And they think this, like, simultaneous reward circuit 大脑如火中烧 只是不知道该如何处理而已firing is something our brainsjust don’t know how to handle. 如果以我们的祖先为例 这也确实行得通That actually makes sense if you look at ourancestors. 远古时期 人们每次大都吃一种食物组For eons, people mostly ate one food group 当条件允许的时候at a time, like when it became available— 一天吃肥肉食物 下一天 吃甜蜂蜜 或浆果食物fatty meat one day, sugary honey or berries the next. 他们确实没有太多的其他的选择They didn’t really have the option to do anything else 因为几乎没有食物是包含大量碳水化合物和水because very few foods are naturally richin carbs and fat. 农业使得营养组合混合在食物中变得更加容易Agriculture made it easier to mix nutrientgroups in meals, 但是but it still wasn ’ t 直到150年前 我们开始真正制作until the last 150 years or so that we started actually making 包含具有更多卡路里的所有营养物质的单一食品名目single food items that contain a dozen or more calories of each nutrient type. 所以 对于 绝大部分进化历史So for the vast majority of our evolutionary history, 我们的大脑 不需要努力地评估包含碳水和脂肪食物的营养价值our brains simply haven ’ t had to try to estimate the nutritional value of fatty, carb-filled foods. 研究者也发现 人们并不擅长做这种判断The researchers also discovered that we ’ re pretty terrible at making such judgements. 当他们要求参与者去判断参与者所竞标的在零食中的种类When they asked the participants to guess the calories in the snacks they were bidding on, 当涉及到碳水类食物和组合食物 参与者并不能给出答案they kinda failed when it came to the carb-y and combo foods. 研究者甚至可以把一部分大脑区分为The researchers even identified a part 梭状回of the brain called the fusiform gyrus— 一个基于大脑的重要的长条区a long strip that’s at the base of our brains—that ’ s important 用来做出各种判断 所以for making these kinds of estimations. So, 如果我们不能if we can’t 在涉及到碳水时 评估分类estimate calories very well when carbs are involved, 我们会从脂肪碳水组合物中得到更大的奖励and we’re getting a bigger reward from thosefat/carb combinations, 需要花费更多去解释为什么that goes a long way to explaining why 会如此困难it’s so hard 当我们携带甜甜圈作为食物 而我们不能吃太多甜甜圈for me to not eat more donuts when somebody brings donuts in to work. 我的意思不是你不能携带甜甜圈 把它当食物I ’ m not saying I resent you for bringing the donuts in, 但是 就是要少吃but it’s just hard, okay? 甜甜圈很好吃They’re so good! 即使不好吃 我也要一直吃 最终Even when they’re not that good I keep eating them. Eventually, 科学家可能用这些信息scientists may be able to usethis information 更好地解释吃得过多和肥胖to better understand overeating and obesity. 幸运地是 这意味着And hopefully, that means they 他们能想出can come up with ways for people 让人们做更好食物选择的方法to make better food choices, 即使他们被垃圾食品所环绕even when they’re surrounded by lots of junk, 正如我们经常吃垃圾食品一样as we so often are. 我们下一个主题 更古怪Our next topic, weirdly enough, 是关于众多稀有天然食物的一种is about one of those rare natural foods 这种食物包含丰富的碳水化合物和脂肪that’s rich in the carb and the fat department. 非洲猴面包树能生产一种包括含淀粉的果肉和含大量脂肪的果核的水果African baobab trees produce fruits that have a starchy pulp and a fatty seed. 这样So in a way, that makes them, like, 这就像是一种原始的垃圾食品kind of a proto-junk food, 除此以外 它们还包含纤维和蛋白质except that they’re also packed with fiber and protein, 所以这种水果也十分健康so they ’ re pretty healthy. 问题是The problem is, 《天然植物》杂志这周发表了一篇文章a new report out this week in the journal Nature Plants 文章指出 很多最大的年龄最大的猴面包树found that many of the biggest and oldestbaobabs— 已经养活人们超过一千多年了some of which have been feeding people forthousands of years— 这些树正在莫名其妙地消亡are inexplicably dying out. 国际研究对于调查了全球60棵树The international research team surveyed 60trees across the globe, 检测他们的健康程度 和他们的体积checking on their health, measuring their size, 提取木头样品来评估他们的树龄and taking wood samples to estimate their ages. 你也可能觉得你可以While you might think you could just, like, 像判断其他树的树龄一样 通过计算树的年伦来评估树龄count the rings like other trees, 猴面包树一生可以生长超出树干的年伦baobabs can grow more than one trunk throughouttheir lives. 这样 有时会创造出一种看起来是一个大的树干These sometimes fuse together, creating whatlooks like one big trunk, 但是中部是空白的假象but inside there are open spaces. 这种复杂确实很难去判断他们的树龄And this complexity makes it really hard todate them— 猴面包树的结构很古怪the baobab ’ s structure is so wacky 树龄并不能说明什么 所以that rings don ’ t tell you very much. So, 科学家依靠特殊的放射性碳来记录日期the scientists relied on special typeof radiocarbon dating instead. 这种方法 使用很少部分的样品In this method, you use a very small sample 从大量的树中from multiple parts of the tree, 计算所有种类碳原子的数量and count the number of all the different types of carbon atoms, 你就能得到一个日期评估结果which can then give you a date estimate. 队伍发现很多树The team found that many trees were more 超过了一千年than 1,000 years old, 其中有一棵树几乎有2500 的树龄including one that was nearly 2,500 years old, 这个星球上最古老的开花的树 但是making it the oldest flowering tree on theplanet. But, 在一个可怕未预期的扭曲中 他们也发现in a horrible and unexpected twist, theyalso discovered that 13棵最古老树中有9棵9 of the 13 oldest trees and 5 6棵最大的树中有5棵 已经死了of the 6 biggest trees were dead 活着之前一个树干已经死亡or had at least one trunk that was dead. 死亡发生在上一个12年之内And those deaths all happened within the last12 years. 科学家不能解释这是为什么Scientists aren’t sure why this is happening, 虽然他们觉得天气变化是主要原因although they suspect climate change mightbe to blame. 越来越高的温度 和越来越多的干旱With warmer temperatures and more drought, 树极力争取足够的水分来支撑他们庞大的框架the trees might be struggling to get enough water to support their large frames. 但是 需要进一步研究来确认这一怀疑But further research is needed to confirmthat suspicion. 所以 现在 关键在于So now, the race is 弄清楚到底发生了什么on to figure out exactly what ’ s going on 在我们频道永远消失之前before we lose these iconic trees for good. 谢谢收看科学秀的本期视频Thanks for watching this episode of SciShow! 如果你想继续了解If you want to keep learning 我们生活的这个古怪的世界about this wacky world we live in, 包括实时观看最新信息including staying up to date with all the new, 令人振奋的科学研究exciting scientific research, 请前往油管科学秀网站观看我们的视频you might want to head on over to YouTube.com/SciShow 观看一系列相关视频 并点击浏览按键to watch a bunch of episodes and also click on that subscribe button. 谢谢Thanks! [音乐][OUTRO ♪]
  • 2021-09-02如何修复古式真皮家具[soft music][轻音乐] [vacuuming][吸尘] Hi. My name’s Steven.嗨 我是Steven Today we’re gonna walk through how to restore a leather chesterfield.今天我们将介绍如何修复真皮沙发 This chesterfield chair we have in眼前的这个沙发 has got a lot of grease marks on the arms,扶手上有许多油渍 scratches on the seats,坐垫上有划痕 and grease marks on the head areas.靠枕上也有油渍 We’re just gonna be restoring it to its original look.而我们要将它恢复原样 [scrubbing][擦洗] So, to start off the process,那么 在开始修复时 we’ll always clean down the sofa with the Ultra Clean,我们都会用奥托克林来清洁沙发 basically just a leather cleaner.实际就是皮革清洁剂 This removes all the dirt and grease, any oils on the surface.它可以去除沙发表面的所有污垢和油脂 This customer liked the old antique look,这位顾客喜欢古色古香的外观 so we would need to mask the studs off,因此我们需要将饰钉蒙起来 just to stop them from getting any overspray on them,这样可以避免粘上过喷的喷剂 so they don’t get damaged when we’re doing the repair process.也就不会在修复过程中遭到破坏 The next stage is the leather prep.下一步是喷上皮革预处理剂 So, before we restore the color,那么 在恢复颜色之前 we will need to remove the existing finishing coatings from the leather.我们要去除皮革上现有的装饰涂层 The leather prep does this,使用皮革预处理剂就能做到 and it allows us to extract all the cracks and the oils from the sofa.我们用它来清理沙发上所有的裂缝和油脂 It can also remove any sort of cracking that’s in the painting coating.它还可以去除油漆涂层中的各种裂缝 Some areas that have cracking might be in the actual leather,一些裂纹可能出现在真皮部位 but the leather prep can sometimes但是皮革预处理剂偶尔也能 remove all of the cracking from the existing painted coatings.去除现有涂漆层上所有的裂纹 This can be seen on the arm areas here.比如扶手这块 We will then apply the leather degreaser然后 我们将皮革脱脂膏 to the hand areas and the head areas涂抹在扶手和靠枕上 and any areas that are feeling greasy.涂抹在任何感觉油腻的地方 This is because they get all of the natural contact with the skin,因为这些地方与皮肤有自然接触 so all of the oils from the head and the hands,所以头和手上的油脂 they’ll soak through into the leather.都会渗透到皮革中 This is an essential part of the process.这是修复过程中很关键的一步 If the oils aren’t removed from the heads and the hand areas,如果不去除扶手和靠枕上的油脂 then the colorant won’t stick, when we come to that stage.那么之后上色时 着色剂就无法牢固 So what we are doing here is所以 我们这一步就是 putting the degreaser paste on and letting it dry.涂上脱脂膏 等待干燥 It may take an hour or two to dry.可能需要一两个小时才能干燥 So, as it dries, it dries into a white powder.脱脂膏会逐渐干燥成白色粉末 If this powder dries a yellow or a greasy color,如果粉末干燥后呈现黄色或油脂色 this means it’ll need another coat applied.就意味着需要再涂抹一遍 Once it is dry, if it is all white,一旦干燥 变得全白 then that means all of the grease has been removed.就说明所有油脂都去除干净了 So, once we are happy that all the leather degreaser has worked,因此 当脱脂膏的效果令我们满意时 we will then clean it off again.就要再次将沙发清理干净 This is essential just to get all of the remaining grease and dirt这么做有利于清理 and all the bits of leather degreaser that’s still in the buttons所有残留在纽扣 甚至渗入到皮革里的 or that might have got into the leather.油脂 污垢 以及脱脂膏 We will need to remove these with the Ultra Clean again.我们还要再次使用奥托克林来清理 We will then need to remove all the grime and the dirt from inside of the buttons.然后要清除纽扣里的灰尘和污垢 We do this with compressed air.我们借助压缩空气来操作 This is so we can get right underneath the buttons这样就可以清洗到纽扣下面 and the hard-to-reach areas.和难以触及的地方 So, the alcohol cleaner is the next part of the process.接下来 使用酒精清洁剂 This neutralizes the leather surface.它可以中和皮革表面 It removes all the silicons that may not be soluble in the leather prep,去除不溶于皮革预处理剂的硅 so it’s important to use alcohol cleaner to所以 使用酒精清洁剂有助于 ensure the repair products adhere properly.确保修复产品附着牢固 Then we will move on to the repair.然后继续修复 修补 Cracks will happen with just general wear and tear日常的磨损会导致皮革产生裂纹 and constant pressure on the leather,持续受力亦是如此 which will crack the existing finish这两个因素导致沙发饰面开裂 and will crack the color from the leather.以及皮革掉色 We’ll be using the leather binder to fix some of these cracks.我们会使用皮革粘合剂来修复部分裂纹 So, the leather binder is just a thin liquid,皮革粘合剂就是一种稀薄的液体 and it’s used for strengthening heavily worn or cracked leather.用于加固严重磨损或开裂的皮革 It just soaks deep into the fibers and repairs minor scuffs.它直接渗入纤维中 修复轻微的磨损 As you can see, on these arms we have a few minor scuffs,如你所见 扶手上有一些轻微磨损 which the leather binder will be able to repair.皮革粘合剂可以修复好它们 Sanding the job down is also a vital part of the process.打磨也是修复过程中很重要的一步 This is to ensure that the leather gets a nice smooth feel to it.打磨是为了确保皮革触感光滑 We need to constantly run our hand around the leather sofa,我们需要不断用手触摸沙发皮面 just to feel we’ve got all the right areas with our sanding pads.以便感知各处是不是都打磨好了 So, if you’ve gone further down the line要是已经顺着这条线打磨过了 and one area hadn’t been sanded,但是漏了某一块 we would then have to use a heavier sanding pad,那么 我们就要用更细的打磨垫 which then might remove the existing color that we’ve already sprayed on,这就可能会破坏已经喷好的颜色 which would then mean we would have to go back to that stage.也就是说 我们要再喷涂一遍 So it’s very important that we keep on top of the sanding.所以做好打磨至关重要 The toughest part of this restoration is probably going to be the arms,这次修复最难的部位可能是扶手 as they’ve got a bit of cracking on.因为它们已经开裂了 And maybe the outside back.还有沙发的背面 Has some quite small tears,上面有一些小磨损 so we’re gonna have to use some flexi filler那么 我们要用一些弹性填充剂 to try and repair these areas.来修复这些地方 It dries clear, so it’s easily colored over.干燥后不着痕迹 很容易上色 This can take just a few minutes to dry.大概几分钟即可干燥 We will apply just enough pressure with a palette knife使用调色刀 适当用力 so that the flexible filler covers all of the damaged area.弹性填充剂就可覆盖受损区域 The excess is then removed so it doesn’t cause a ridge around it然后刮去多余的 这样周围就不会凸起 and so the surface is nice and smooth.表面才能整洁光滑 Once we are happy it is fully filled,一旦填充得令人满意后 we will then dry the area and then move on to the next stage.就要等待干燥 接着进入下一个步骤 [spraying][喷色] So, the base color is applied to the chair first.先给座椅喷上底色 The base color on this chair is called an antique red.这张座椅的底色是复古红 We have this color saved in our database,我们的数据库中保存了这种颜色 as it’s the most common color on an antique chesterfield.因为它是经典长靠沙发中最常见的颜色 And the majority of chesterfields have the antique red base and the antique topcoat.大多数长靠沙发都是复古红色的底漆和面漆 So, the antique red base color is applied with light coats我们使用重力式自动喷枪在浅色面漆上 using a gravity-fed spray gun.覆盖了一层复古红底色 We will slowly build it up until we are happy that it has a full base color on.慢慢上色 直至底色效果令人满意 We will dry in between every single coat每上一层色 我们就要等待干燥 and repeatedly sand,反复打磨 just to give the leather a nice smooth feel.直到感觉皮面非常光滑 Once we are happy with the base color,当底色上好了 we will then move on to the buttons.我们就要开始处理纽扣 As you can see, we need to darken the buttons down.如你所见 我们要将纽扣喷成深色 All of the chesterfield buttons are always dark.所有的长靠沙发纽扣都是深色的 So, after we’ve sprayed the antique red base color on,喷好了复古红色的底漆之后 we’ll then apply the antique topcoat.我们就要喷上复古式的面漆了 We start with the buttons, and then we’ll move on to the pleats.先喷纽扣 然后喷褶皱处 As we darken the pleats,褶皱颜色变深时 it creates a diamond effect,会产生钻石般的效果 which we will then color in with a topcoat,之后我们会喷上面漆 allowing the base color to come through the sofa.让沙发的底色透出来 Gives it that antique two-tone effect.赋予沙发古色古香的双色调效果 The leather finish is applied last.最后喷上皮革涂饰剂 The leather finish we are using here is a gloss.我们所使用的是光泽型 It’s a signature of chesterfield sofas这也是长靠沙发的一个标志 and gives it that antique look.可以赋予沙发古典韵味 [soft music][轻音乐]
  • 2021-09-02思想实验“体验机”:快乐是美好生活的秘诀吗?Here is the Thought Experiment. 这里是《思想实验》 A good life isn’t just about having a good time.美好生活不只是过得愉快 It’s about having a true time.更要活得真实 《电视点子》 In this episode, we’re going to talk about本期节目 我们要讨论的是 a philosophical thought experiment concerning simulated experiences.一场关于仿真经历的哲学思维实验 But before we do that, I have a question for you.在此之前 我先问大家一个问题 How ya doing? Really, tell me. I want to know.你过得好吗?说真的 告诉我 我想知道 I know politeness dictates that you’ve got to be like, Good. And you?你也许会礼貌地回答:“很好 你呢?” But really, dig deep.但 你要深思熟虑 I don’t care about your day.我问的不是你今天过得怎样 I want to know if you’re having a good life.我想知道的是 你是否拥有美好生活 What even makes a good life?怎么才算美好生活? It’s a tough question, so here’s a little bit of guidance.这个问题比较棘手 我稍微给点提示 Is a good life having lots of pleasurable experiences?有很多快乐的经历就算拥有美好生活吗? Is that the best situation?那就是生活最美的样子吗? Here, I’ll give you a second to think.给你时间思考一下 有快乐的经历就算拥有美好生活吗? If you said yes,如果你回答“是” Are you sure?你确定吗? Hedonism is a philosophy that argues享乐主义哲学认为 a good life is one that is filled with pleasure.“美好生活是快乐至上” Historically, hedonism has gotten kind of a bad rap.古往今来 享乐主义一直备受诋毁 People confuse that with indulgence,人们把它和放纵 堕落 vice,bacchanalian revelry, and outright sin.纵酒狂欢和彻头彻尾的罪恶混为一谈 But a hedonistic life isn’t necessarily extravagant or debaucherous.但享乐主义并不一定就是奢侈或放荡 In fact, ancient Greek philosopher Epicurus —实际上 古希腊哲学家伊壁鸠鲁 one of the first and most famous hedonists–作为最早也是最著名的享乐主义者之一 encouraged a life of detachment and temperance.他提倡过一种超然而适度的生活 Those were his pleasures.这才是他所谓的“快乐” Life of the bacchanal, that’s not Epicurus.每天沉溺饮酒作乐 并非伊壁鸠鲁主义 What this means is that how you do hedonism就是说 你定义快乐的方式 is determined by what you consider pleasure.决定了你奉行享乐主义的方式 There are lots of ways to determine what counts as pleasure.定义快乐的方式有千千万万种 But for our purposes,但为满足实验需求 we’re going to focus on one– preference hedonism,我们只聚焦其中一种——偏好享乐主义 where pleasure is any mental state that is desired.即 快乐是任何让人渴望的心理状态 This is just one interpretation of hedonism这只是享乐主义的其中一种解释 and to simplify it at that.如果你想简要了解它 Link Doobly-Doo for more.打开Doobly-Doo链接了解更多 Preference hedonism says,偏好享乐主义认为 if you desire the experience of spending all day in the ball pit如果你想在查尔斯娱乐城的 at a Charles Entertainment Cheese fine diversion establishment,海洋球里玩上一整天 then doing so is pleasurable for you.那这种行为对你来说就是愉悦的 And that means your life is good.这意味着你的生活很好 Counting blades of grass, playing the tuba,数草叶 吹大号 building a castle of junk– all great.用垃圾造城堡 这些都是可以的 Hedonism ain’t going to judge,享乐主义不会歧视任何一种偏好 which gets a little bleak if what’s good for you is bad for others.如果对你有利的事对其他人不利 那就不太妙 But basically, if you’re having the experiences you want,但大多数情况下 享乐主义认为 hedonism says, you good.如果你做了想做的事 就会快乐 But are you?但你真的快乐吗? This brings us– drum roll please– to today’s thought experiment,这就可以——音乐起——引出我们今天的思想实验 philosopher Robert Nozick’s Experience Machine,哲学家罗伯特·诺齐克的体验机 an attempt to dismantle or at least examine hedonism出自他的《无政府 国家和乌托邦》一书 from his book “Anarchy, State, and Utopia.”旨在试图消除或至少审视享乐主义 The Experience Machine is sort of like the ultimate virtual reality headset.体验机有点像终极的虚拟现实头盔 Its simulations are lifelike and indistinguishable from reality.它的模拟栩栩如生 无法与现实区分开 Even on the neural level,即使在神经层面 no difference between you in the Experience Machine and, well, the experiences.体验机与现实体验之间也没有区别 Nozick writes that super-duper neuropsychologists诺齐克写道 这台“超级神经心理学家” could stimulate your brain so that you would think and feel可以刺激你的大脑 使你思考并感觉到 you were writing a great novel or making a friend自己正在写一本伟大的小说或结交朋友 or reading an interesting book.或读一本有趣的书 All the time, you would be floating in a tank整个过程 你都漂浮在一个 with electrodes attached to your brain.通过电极连接到你大脑的水箱 He then poses the big question.然后他提出了一个大问题 Should you plug in to this machine for life,你是否应该终生接入这台机器 preprogramming your life’s experiences?对你的生活经历预先编程? You can program the Experience Machine你可以对体验机进行编程 to give you any experience让它给你任何体验 even a whole lifetime of pleasures,甚至是一生的愉悦感 even temperate and detached pleasures.甚至是适度 超然的愉悦感 Pick your poison– the point being living in the machine选择你的毒药——生活在机器中 you’d have more net pleasure in it than IRL.你会获得比现实生活更多的净乐趣 The only practical difference is唯一的实际区别是 what your physical body is up to.你的身体在做什么 It’s up to nothing.什么都没做 Do you do it? Do you plug in?你想这样做吗?你想插入吗? Is that a good life?那是美好的生活吗? I’ll give you some time to think.给你点时间思考一下 你愿意进入体验机吗? [MUSIC PLAYING] Time’s up.时间到 Nozick says诺齐克说 the true hedonist who thinks the good life is pleasurable experiences认为“美好生活是愉快经历”的真正享乐主义者 must do it.必须做到这一点 Hedonism says more pleasure equals a better life.享乐主义认为 更多的快乐等于更好的生活 And pleasure is any desired mental state,而快乐是任何让人渴望的心理状态 which is exactly what the machine produces.这些正是由机器创造 So plug them in!因此 插入吧! Nozick wagers, however, that most people然而 诺齐克打赌说 大多数人 would regard the Experience Machine with extreme skepticism会对体验机产生极大的怀疑 and shouldn’t plug in.因此不会插入 Now, if you’re like me you may agree.如果你跟我一样 你可能会认同 And one of the first places your mind goes is “The Matrix”–你首先能想到的就是《黑客帝国》 fake experiences, people batteries, ignorance is bliss.虚假经历 人类电池 无知是福 But a closer analog I think is “Total Recall”– the original on Mars–但我认为更接近的是《全面回忆》(原版中火星上的情节) or even Philip K. Dick’s short story甚至是菲利普·K·迪克的短篇小说 “We Can Remember It For You Wholesale”《我们可以为你全部记住》 where Douglas Quail– Quaid in the movies–书中的道格拉斯·奎尔(电影中的奎德) elects to undergo a procedure developed by Recall,选择接受“回忆”公司开发的程序 Incorporated whereby he sits in a machine他坐在机器中 and is given false memories of a trip to Mars as a secret agent.被赋予了前往火星的秘密特工的虚假记忆 Central to the tension of the story is the question of, wait,故事张力的核心在于…… 等等 did this really happen?这真的发生了吗? Whether Quail’s experiences are true or not奎尔的经历是否真实 determines how important they are to the story.决定了这对故事有多重要 Nozick’s take on the Experience Machine is similar.诺齐克对体验机的看法与此类似 His wager is that, even as card-carrying hedonists,他打赌 即使作为名副其实的享乐主义者 we wouldn’t just care about我们也不会只在乎 experiences being fun or challenging, exciting or pleasurable.有趣的 充满挑战的 令人兴奋或愉悦的经历 We’d also care if they’re true.我们也会关心它们是否真实 And that is what makes them important.这就是它们的重要所在 And broadly speaking, if that’s the case then从广义上讲 如果是这种情况 hedonism is false, isn’t it?享乐主义就是错误的 不是吗? The best life then isn’t simply one因此 最好的生活不仅仅是 with the most pleasurable experiences拥有最愉快经历 but rather one with true experiences.而是拥有真实经历 According to Nozick, there’s an appreciable difference根据诺齐克的说法 在经历和实践之间 between what one experiences and what one does存在着明显的区别 and that people value doing more than mental states that resemble doing.还有 相比于模仿实践的心理感受 人们更看重实践 If you or I were to get into the Experience Machine,如果你或我要进入体验机 he may wager, upon exiting we’d say,他可能会打赌 我们在退出时会说 huh! That was fun.“呵呵!蛮好玩的! Shame it wasn’t real, though.可惜这不是真的” Another way to think about this abandons one type of machine for another.对此 另一种方法是将体验机换成另一种机器 Consider Truman Burbank of “The Truman Show”想想《楚门的世界》的楚门·伯班克 and the well-oiled machine和运转良好的“社会机器” that is the cast and crew that works tirelessly to make his real to him其中的演员和工作人员孜孜不倦地为他创造真实感 but fictional to his audience life what it is.但这对观众来说却是虚构的 Up until things start to unravel,直到一切瓦解之前 the hedonist has to say Truman has a great life.享乐主义者都可以说楚门过着美好的生活 Maybe he’s being lied to, but he has no idea.也许他被骗了 但他不知道 He’s an on-top-of-the-world lucky son of a gun.他是举世无双的幸运之子 But if what we care about is truth,但是如果我们关心的是事实 then we may have to say那么我们可能不得不说 Truman’s life is garbage even before he gets wise.甚至在楚门认清一切之前 他的生活就是垃圾 Those people are lying to him,那些人向他撒了谎 perpetrating what you could call an unexperienced harm that你可以称之为“未经历的伤害” makes his life worse even if he never directly experiences it.即使他从未直接经历 这也使他的生活变得更糟 On the flip, though, there must also be unexperienced benefits.但另一方面 肯定也有未经历的好处 His life could be going great即使这感觉像一场丑陋的表演 even if it feels like a total poop show.他也可以过得很好 People love him and respect him.人们爱他并尊重他 They support him, though he never directly experiences it.他们支持他 尽管他从未直接经历过这些 “The Truman Show” charts this whole territory《楚门的世界》将整个图景 from unexperienced harms to unexperienced benefits从“未经历的伤害”描绘成“未经历的好处” and shows how a good life is not a straightforward thing.并证明 美好生活不是一件简单的事情 Like Nozick’s Experience Machine,就像诺齐克的体验机一样 “The Truman Show” illustrates《楚门的世界》表明 how pleasurable experiences sort of pale in comparison to what is truly the case,与常常超出经历之外的真实情况相比 a thing that is often beyond experience,令人愉悦的经历是多么苍白的东西 which is all Nozick’s mental pod offers–而这正是诺齐克的体验机能提供的全部 experience, nothing else except for maybe, like, nutrient goop,除了经历别无其他 至多还有营养液—— everything the body needs.提供身体所需的各种营养 which brings us actually to some interesting complications这实际上给我们带来了一些 with the Experience Machine thought experiment not having to do with nutrient goop–关于“体验机思想实验与营养液无关”的有趣意外 well, sort of not having to do with nutrient goop.好吧 与营养液或多或少有点关系 In “Welfare, Happiness, and Ethics,”加拿大哲学家伦纳德·萨姆纳在 Canadian philosopher Leonard Sumner says《福利 幸福与道德》一书中说 it’s hard to imagine anyone would abandon很难想象有人会放弃 their body, family, friends for permanent feel-good pod residence,他们的身体 家人和朋友来获得永久舒适的休眠舱 that even a keen hedonist would be skeptical of Experience Machine Corps’s promises,即使热衷享乐主义的人也会怀疑体验机公司的承诺 the fidelity of the output, or the robustness of the tech in the case of a technological malfunction–输出的保真度 或遇到技术故障时的稳定性 function– function– function. [STATIC]性…… [静电噪音] Basically, if someone has family or friends;基本上 如果一个人有家人或朋友 has seen a movie in 4K and thought,看了一部4K电影 然后想 oh, it doesn’t look all that great;哦 看起来也不怎么样 or if the movie was, in fact, “Total Recall”– or “The Matrix”–或如果电影实际上是《全面回忆》或《黑客帝国》 they’d see the EM and go (PROLONGED) uh, no thanks.他们会看着体验机说(拖长音)“嗯 不用了 谢谢” A world without relations or responsibility一个没有亲缘关系 不需要负责任 and with perfectly trustworthy technology拥有完全可信赖技术的世界 is totally unlike our own–完全和我们自己的世界不同 “alien,” Sumner writes, concluding“迥异” 萨姆纳总结中写道: “who knows what we would choose in a world like that?”“谁知道在那样的世界中我们会选择什么?” Sumner says that EM becomes more fruitful萨姆纳说:“如果我们想象‘不那么宏大的幻想’ if we imagine “less-grand illusions.”体验机将变得更加富有成效” He suggests imagining highly-realistic movies and video games他建议想象高逼真的电影和视频游戏 as opposed to simulated life experiences,而不是模拟生活经历 which, I mean, might not be too much of a stretch我的意思是把我们的娱乐技术 imagining that our entertainment technology’s a kind of temporary residence Experience Machine.想象成一种临时居住的体验机可能并不算太离谱 And after spending some time with your VIVE当花了一些时间在VIVE上 or getting sucked into a particularly good book,或沉迷于一本特别好的书之后 do you stop and say, well, that was great–你会停下来说 “太棒了! shame it wasn’t real, though?可惜那不是真的”么? Stories and video games are not our lives.故事和视频游戏不是我们的生活 But for the moments that we’re engaged with them,但是 在与它们建立联系的那一刻 we may reasonably say我们可以合理地说 they’re experienced as part of our lives– often meaningfully它们作为我们生活经历的一部分 通常是有意义的 and as a mental state more so than a direct experience,它们是一种心理状态 而不是直接的经历 by which I mean, as engrossing as “Game of Thrones” is,我的意思是 它们像《权力的游戏》一样引人入胜 you haven’t had the experience of being crushed by a phalanx,尽管你没有被方阵击溃的经历 though you may feel like you have.但你可能会觉得你有过 Insofar as immersive entertainment experiences contribute to them,就沉浸式娱乐对此的贡献而言 would we say our lives are我们是否会说 我们的生活 “not circumstantially but intrinsically worse”– as Sumner puts it–“并非视情况而定 而是本质上就更糟糕”(引自萨姆纳) because those experiences aren’t real?因为这些经历不是真实的? I don’t think so.我不这么认为 For one, the experience of media is just as real as unmediated experience.一方面 有媒介体验与无媒介体验一样真实 They’re just different types of real experience.它们只是不同类型的真实体验 Put more grandly,更广义地说 something doesn’t have to be actual to be impactful.有些事情不一定要实际才能产生影响 Wait, doesn’t this bring us back to full-on hedonism?等等 这是否会使我们重返享乐主义? Didn’t we say like two minutes ago我们大约两分钟前不是说过 that a good life is a true life with true experiences?“美好的生活就是具有真实经历的真实生活”吗? [SIGHS DEEPLY] How do we reconcile all of this?[深思] 我们如何协调所有这些? Well, Sumner has an idea.好吧 萨姆纳有个主意 He writes, “The lesson of the Experience Machine他写道:“体验机器教会我们的 may be not that mental state theories are deficient as accounts of the nature of welfare可能不是 心理状态理论不足以说明“幸福”的性质 but that welfare attracts only one dimension of the value of life.”而是“幸福”仅包含了生活价值的一个维度” In other words,换句话说 a good life is not comprised of only pleasurable experiences.美好的生活不只是愉悦的经历 Pleasurable experiences are just one part of a good life.愉悦的经历只是美好生活的一部分 The other parts– well,至于其他部分 好吧 I’ll let you figure out what those are in the comments.我会让你在评论中给出答案 But if you need some help,但如果你需要提示 think about what you would worry about想一想 如果你准备踏入体验机 if you were getting ready to step into the Experience Machine享受一生超然而适度的快乐 for a lifetime of detached and temperate pleasure.你会担心什么? Let us know in the comments.让我们在评论中知道 I’ll respond to some of them in next week’s comment response video.我将在下周的评论回复视频中回答其中一些问题 In this week’s comment response video,在本周的评论回复视频中 we talked about your thoughts regarding我们谈到了你对 the ruiners of all things, millennials.万物破坏者——千禧一代的看法 If you want to watch that one,如果你想观看 you can click here or find a link in the Doobly-Doo.可以点击此处或在Doobly-Doo找到链接 We have a prep thread going我们有一个准备帖 for the next thing we’re reading for the Idea Channel Book Club,为创意频道读书俱乐部准备下一本书 which is “The Library of Babel” by Jorge Luis Borges.即Jorge Luis Borges的《通天塔图书馆》 We’re going to be discussing that on the subreddit next week.我们下周将在subreddit上进行讨论 If you want to go check out the prep thread,如果您想查看准备帖 it has some awesome supplementary material,它有一些很棒的补充材料 some sort of preliminary ideas.和一些初步的想法 It’s really good, already super interesting.这真的很好 已经很有趣了 We’ll put a link to that in the description, too.我们也将在视频简介中添加一个链接 And in case you missed it, I was on the most recent episode以防错过 我在《艺术任务》的最新一集中 of The Art Assignment talking to Sarah about five of my favorite works of art,与莎拉谈论了我最喜欢的五件艺术作品 Including some Robert Ashley stuff, Agnes Martin,包括罗伯特·阿什利的一些作品 还有阿格尼丝·马丁的 this punk rock show that I went to this one time in 1999.还有1999年我去过的一次朋克摇滚表演 We’ll put a link to that in the description, too.我们也将在视频简介中添加一个链接 And if you aren’t already subscribed to The Art Assignment,如果您还没有订阅《艺术任务》 you gotta. You just– you gotta.那就订阅吧 你只需订阅 We have a Facebook and IRC and a subreddit.我们有Facebook IRC和subreddit账号 Links to those also in the Doobly-Doo.这些链接也在Doobly-Doo里 And the tweet of the week comes from theodinspire,还有来自theodinspire的一周推文 who points us towards the Chrome extension它提到了我们的谷歌扩展程序 that I meant to mention in last week’s episode我本想在上周视频中提及的 but totally forgot that turns the word “millennials” into “snake people”但完全忘记将“千禧一代”一词转换为“蛇人” because that’s what we are.因为我们就是“千禧一代” And last but certainly not least,最后但同样重要的是 this week’s episode would not have been possible or good如果没有这些名副其实的享乐主义者的辛勤工作 without the very hard work of these card-carrying hedonists.本周的节目将不可能完成或者成功 [WHOOSHING][呼嘶] [DING][叮] [MUSIC PLAYING][音乐响起]
  • 2021-09-02大堡礁是如何形成的?20,000 years ago, this area wasn’t even underwater.两万年前这片区域甚至都没在水下 It was covered with eucalyptus and paper bark forests.而是被桉树和纸树皮林所覆盖 And it was home to animals commonly found on the Australian plains.它是澳大利亚平原上常见的动物的家园 Aboriginal people would have lived here too,土著人也居住在这里 hunting wildlife in areas狩猎野生动物 that are now deep underwater.这里现在是深海 Then 10,000 years ago,一万年前 at the end of the last Ice Age,在最后一个冰河时代的末期 ice at the poles melted and sea levels rose all around the world,两极的冰融化使全世界的海平面都上升 flooding this low lying coast.淹没了这片低洼的海岸 Stories of the Great Flood are still passed down in Aboriginal culture today.关于大洪水的故事仍然流传在今天的土著文化中 As the sea rose随着海平面上升 corals began to grow on the Rocky fringes of the continental shelf,珊瑚就开始在大陆架的岩石边缘生长 creating the Great Barrier Reef we see today.创造了今天我们所看到的大堡礁 These shallow tropical waters are clear and warm这些热带浅水清澈温暖 perfect conditions for coral to thrive.非常适合珊瑚的生长 Sheltered behind this long strip of reef,而隐藏在这片狭长的暗礁后面 a lagoon was born,一个泻湖就诞生了 an area of protected water larger than all of Great Britain.是比整个英国面积都大的受保护水域 With it came a new coastline of shallow sandy waters.随之而来的是一条新的浅湾海岸线 The rising sea cut off areas of high ground,上升的海水把高地隔开 creating the 600 islands that dot the lagoon.在泻湖上形成了600座小岛 Some are little more than rocks.有些比岩石大不了多少 Others substantial mountains covered in Woodland.其它的则是被森林覆盖的巨大山脉 The Great Barrier Reef is so large大堡礁是如此的大 that it can be seen from space,以至于在太空都能看到 quite an achievement considering the size of the creatures that built it.考虑到建造它的生物的大小 这是一项相当大的成就
  • 2021-09-02为什么月亮会变成红色?If there’s one thing we can rely on,如果说有一件事情我们能永远相信 it’s that the moon will always be there.那就是月亮会一直在 Night after night.夜夜如此 But our long-serving lunar satellite但作为长期守护地球的卫星 is actually changing,月球其实一直在变 and in stranger ways than we could have have ever imagined.并且变化奇异 令人难以想象 This is Unveiled,欢迎来到《揭秘未知》 and today we’re answering the extraordinary question;本集视频会解开一个奇异之谜: why is the moon turning red?为什么月亮正变红? Are you a fan for facts?你痴迷于真相吗 Are you constantly curious?你一直充满好奇吗 Then why not subscribe to Unveiled是的话 快来订阅《揭秘未知》 for more clips like this one?有更多这样的揭秘视频等你 And ring the bell for more fascinating content!记得设个提醒 获取更多精彩内容! The Moon Mineralogy Mapper is a device月球矿物测绘仪 designed by NASA’s Jet Propulsion Laboratory由美国宇航局喷气推进实验室设计 to study the composition of the moon.用以探究月球的组成成分 It’s what’s known as a spectrometer,它是一种光谱仪 which is a machine that produces spectral maps;即能够生成光谱图的机器 which are maps that show the exact chemical arrangements光谱图能显示指定行星或卫星的化学组成 of any given planet or, in this case, satellite.本视频中指定的是作为卫星的月球 The Moon Mapper works because every element on the moon月球上每一种元素发出的光波长不同 emits a different wavelength of light on the electromagnetic spectrum,显示在电磁波谱上自然各异 so it meticulously records these to provide us月球矿物测绘仪就会仔细记录这些信息 with some of the most detailed images we’ve ever seen.从而呈现出我们能看到的最为详实的图像 It was this same mapper, in fact,也正是这台测绘仪 that first detected water on the moon in 2009.在2009年首次探测出月球上存在水 In 2020, scientists re-examined some past data2020年 科学家们再次研究 from the Moon Minerology Mapper;以往通过月球矿物测绘仪获得的数据 data that was originally gathered as part of a survey taken twelve years earlier,这是12年前 月球矿物测绘仪 back when the mapper had been installed被安装在印度月球探测器月船1号上时 on Chandrayaan-1, an Indian spacecraft.在探测过程中最早得到的数据 Upon looking again, the scientists – from the University of Hawaii – discovered something经过再次研究 夏威夷大学的科学家们 previously thought to be completely impossible.发现了之前认为绝对不可能的事情 Analysing the lunar poles in particular,仔细分析月球两极的光谱 they appeared to be going rusty.会发现月球两极似乎正在生锈 Specifically, the mapper identified hematite, an iron oxide具体来说就是 测绘仪识别出了一种氧化物:赤铁矿 produced when iron meets water and oxygen, leaving rust.也就是铁暴露在氧气和水中产生的铁锈 The problem here is that问题在于 the moon shouldn’t have enough water or oxygen for rust to form,月球上没有足够的水和氧气能生成铁锈 so how did it get there?那铁锈从何而来? Well, it most likely has a lot to do with our planet, Earth.这就跟我们的地球有很大关系了 The most straightforward theory is that最直接的推测是 for at least 2.5 billion years,在过去至少25亿年中 Earth’s plants have been pumping out oxygen,地球上的植物源源不断产生氧气 and the moon has picked up some of that.而月球获得了其中一部分 We can find proof of this in certain isotopes of oxygen在目前发现的月球氧气中 that have now been found on the moon,某些同位素来源于地球 because they’re isotopes that originate from Earth.这就为这一推测提供了一些证据 The leading idea is that目前最好的解释是 when the moon passes through Earth’s magnetotail,当月亮通过地球磁尾 which is the trail the planet leaves behind as it orbits the sun,即地球绕日时磁场在地球后侧的延伸 it’s then subjected to at least a little bit of our world’s oxygen.至少有一小部分地球氧气可能到达月球 This happens only for short periods, but regularly.这一过程时间不长 但会定期发生 Although it still doesn’t completely solve the mystery.但这种推测仍未完全揭开谜底 Because, what about the water?因为水的来源还未知 While we know that the moon does have ice,虽然我们知道月球上有水冰存在 the rusty hematite found by the mapper但月球矿物测绘仪发现的赤铁矿 was not close enough to these deposits.离发现水冰的地方很远 The best theory for where the required water至于生锈所需水的来源 comes from, then, is space dust,最可靠的解释是太空尘埃 the idea being that this dust has in some way也就是说 在数十亿年的时间里 reacted with the lunar surface over billions of years,太空尘埃以某种方式与月球表面发生反应 to form traces of water.形成少量水分子 This, combined with the oxygen inherited from Earth,有了水 再加上来自地球的氧气 is what has created the conditions就为月球上铁的氧化 necessary for the moon’s iron to oxidize – for the rust to form.即铁锈的形成创造了条件 We’re still a long way from being able to see但我们现在还无法用肉眼 the effects of this with the naked eye, however.观察到月球生锈的效果 If you go out and look up at the moon tonight,如果你今晚出去看看月亮 you’re not about to notice你没法看到 big red splodges at the top and bottom of it…月亮两极大块的红色锈斑 because, without the Minerology Mapper,因为如果不是月球矿物测绘仪 we’d really have no idea that this was happening.我们甚至不会知道月球正生锈 In fact, it’s thought that the rust is only able to form其实 科学家们认为 在一个月内 for a few days each month.只有几天能发生铁锈反应 it’s just that those days have now added up正是数十亿年间每月几天的积累 over billions of years to cause this interesting phenomenon.才让如此有趣的现象得以出现 This is by no means the first time无疑 这是我们在太阳系中 that we’ve seen this happen in the solar system, though.第一次发现这样的现象 It’s also iron oxide that gives Mars its distinctive colour,同样因为氧化铁 火星有了特别的颜色 putting the “Red” into the Red Planet.名字中的“火”才由此而来 So, if the moon developing hematite is an inevitable process所以 如果月球生锈不可避免 thanks to Earth’s abundant plant life地球又有充裕的植物 and the huge amounts of oxygen our planet produces,还能提供大量氧气 then, one day, the lunar surface could even look a bit like Mars does now.那么月表有一天可能会变得有点像现在的火星 And, unlike so many other long-term ecological or atmospheric changes,并且 与很多其他长期生态或大气变化不同 this is something which should happen regardless of what humans do.人类无法对月球生锈产生丝毫影响 Even if Earth’s environment is severely damaged by human activity,即便人类活动严重破坏了地球环境 and even if we eventually go extinct…甚至即便人类最终灭绝 it’s thought that, given enough time, the Earth will recover.人们认为 有足够的时间 地球还会复原 And it will continue producing oxygen all the while,也就还会持续产生氧气 so its magnetotail will remain,地球磁尾也会继续存在 and the Moon will still slowly be fed月球仍会慢慢获得 all that it needs to gradually rust.其逐渐生锈所需的条件 Sure, if the current predictions play out,当然 如果按照现在的预测 it will take a long time (like, billions more years!)这需要很长时间 比如再有数十亿年 but it’s thought that not even Mars was always red.但据说火星也并非一直都是红色 Its colour is iconic now,虽然现在它的红色极具标志性 but it’s believed that our planetary neighbour但据说这位地球近邻 once had a gray-ish, charcoal look, a long time ago.在很久以前曾有着浅灰色木炭一般的外表 All of which means that这些都表明 we shouldn’t be too worried about the moon going rusty,我们不必太担心月球生锈 even if it does initially sound like虽然最开始这听起来 it might be a bad thing.可能是个坏消息 The creation of iron oxide is a natural process,氧化铁的生成是自然过程 and what we’re discovering now doesn’t mean that我们目前的发现并不意味着 the moon is in some way being damaged.月球受到了某种形式的损伤 It isn’t going to fall apart or collapse月球不会分崩离析 or rust away into nothingness.也不会生锈而消失殆尽 It’s not like an old bicycle that’s been left out in the rain,它不像被扔在雨中的老旧自行车 or a rusty hinge that no longer works,也不像生了锈没法用的铰链 it’s just evidence of the moon目前的发现只证明了 evolving along with the rest of the solar system.月球和太阳系其余各物一样正不断变化 And, regardless, the amount of iron oxide present today且不论目前已生成的氧化铁 is still so negligible that数量微不足道 we need a spectrometer to see it at all.我们需要分光仪才能看到 By the time it becomes significant enough to see from Earth,就算到了我们能从地球上看到的时候 who knows what other changes our planet will’ve also gone through!也没人知道那时地球已经历了什么变化 But if you think a red moon is more interesting但如果你不觉得红月亮可怕 也不为之忧心 than it is scary or worrying,反而觉得很有趣 there’s good news:也有好消息 because, technically,因为严格来说 you won’t have to wait hundreds of millions of years to see one.你不用等上亿万年才能看到红月亮 In fact, red moons are a fairly regular occurrence on the calendar,其实 红月亮会定期出现 just not in the same way.只不过并非因为生锈变红 During a lunar eclipse,在月蚀期间 a phenomenon called Rayleigh scattering –会出现一种现象:瑞利散射 a type of scattering of light它是光散射的一种 – means that the moon appears red in the sky,此时 天上的月亮会呈现红色 in what’s also known as a “blood moon”.这种月亮也被称为“血月” Rayleigh scattering and blood moons但瑞利散射和血月的出现 have zero to do with iron oxide and rust, though,与氧化铁和铁锈毫无关系 and are all to do with how light reaches our eyes,而与光进入我们眼睛的方式有关 with Rayleigh scattering also being the reason瑞利散射也是黎明和黄昏时 why the sky often appears vividly red, especially at dawn and dusk.天空经常变得艳红无比的原因 Culturally-speaking,从文化角度看 blood moons are believed by some to be harbingers of doom,血月在一些文化中是厄运的征兆 but really, physically-speaking,但从自然规律上看 they’re completely harmless-they only indicate a lunar eclipse.血月只象征着月蚀发生 完全无害 Blood moons can also coincide with other lunar events, too,血月也会和其他月球现象一同出现 like supermoons,比如超级月亮 with a supermoon being when a full moon happens precisely超级月亮出现时 月亮要是满月 when the moon is at its perigee而且要恰好位于近地点 (i.e., when it’s the closest it gets to Earth –即月亮离地球最近的一点 which is roughly 221,500 miles away).此时地月距离约为221,500英里 When the moon is at its apogee and is further away,月亮在远地点 离我们非常远时 this can be called a “micro moon”.“微型月亮”就会出现 So, technically, we could also experience a “blood micro moon”,所以严格说来 如果所有条件符合 if all those things aligned.我们也能见到“微型血月” The harvest moon is another of note,而收获月出现的原理则不同 described as the full moon closest to the autumnal equinox收获月是指出现在最接近秋分时的满月 – the date in fall when night and day are the same lengths.秋分是指秋季昼夜等长的那一天 We call it a harvest moon because, traditionally,之所以称之为收获月 farmworkers could continue to reap that year’s harvest long into the night是因为收获月的月光很亮 because the light of this particular moon is so bright.按照传统 农夫能在晚上借月光继续采收 Lots of full moons have nicknames like this, though,很多满月也都有这样的绰号 including the hunter’s moon (which is directly after the harvest moon)比如紧随收获月之后的狩猎月 and the wolf moon (which is the full moon in January).以及狼月 即出现在1月的满月 In 2019, the world was treated2019年 我们曾迎来一次 to an incredibly rare “super blood wolf moon”,极为罕见的“超级血狼月” a full moon happening in January也就是一月份的满月 during a total lunar eclipse when the moon was at its perigee.又赶上月亮位于近地点 出现月全食 Similarly, a blue moon is a lunar phenomenon同样 蓝月也是月球现象其中的一种 that doesn’t really denote any change in colour,尽管这种现象被称为蓝月 despite the name.但并不代表月亮变色了 Most of the time,大多数时候 a blue moon is simply the second full moon in a month,蓝月只是指一个月中的第二轮满月 which happens from time to time但只会偶尔时出现 because the lunar cycle is only around twenty-eight days long,因为一个月亮周期只有约28天 making it shorter than the length of a calendar month.比日历上的一个月要短 It’s where the saying “once in a blue moon” comes from,谚语里会用蓝月表示“千载难逢” because it’s quite rare.就是因为它极为罕见 But the moon can also appear physically blue to us here on Earth, as well,但在地球上也会看到蓝色的月亮 although this is to do with Earth’s own environment rather than the lunar cycle.虽然这与地球自身环境而非月亮周期有关 Whenever there are large amounts of debris in the atmosphere,每当大气层中出现大量碎屑 it can tint the sky different colours,比如火山喷发或森林火灾发生后 like after volcanic eruptions and forest fires.这些碎屑都会让天空变色 And, that colour can sometimes be blue.月亮有时候就会变成蓝色 After the 1883 eruption of Krakatoa,例如 史上最著名的火山喷发之一 one of history’s most famous eruptions, for example,1883年喀拉喀托火山喷发后 it was reported that the moon looked blue据报道 因为空中灰烬太多 because there was so much ash in the sky.月亮看起来就成了蓝色 We also have reports of a blue moon1980年圣海伦火山爆发后 after the eruption of Mount St. Helens in 1980.也有对蓝色的月亮的报道 And finally, the human eye does sometimes perceive standard moonlight as blue,最后 人眼有时确实会把正常的月光视为蓝色 even though it definitely isn’t.虽然月光正常情况下绝不会是蓝色 This is because of the Purkinje effect,这是薄暮现象造成的 which relates to how human eyes are better at也就是说 在暗光条件下 比如夜晚 seeing blues and greens in low light conditions – like, at night相比红色和黄色 – as opposed to reds and yellows.人眼更擅长识别蓝色和绿色 All to say, however, that it’s no bad thing这一切都是说 月球慢慢生锈 that the moon is slowly rusting,并不是什么坏事 even if Earth is ultimately to blame,虽然最后发现是地球造成的 because it’s happening due to completely ordinary –但其实背后的原因是再正常不过 if incredibly rare – astronomical circumstances.但异常罕见的天文学现象 There are also other explanations as to why the moon目前也有很多其他解释来说明 might appear a different colour to us when we look at it,为什么我们看月亮时 它会呈现不同的颜色 but that’s why the moon is turning red.但总之 这就是我们对月亮变红的解释 What do you think?你有什么想法? Is there anything we missed?有什么我们没有涉及的地方吗? Let us know in the comments,留下你的评论 check out these other clips from Unveiled,也欢迎点击《揭秘未知》的其他视频 and make sure you subscribe一定要订阅我们的频道 and ring the bell for our latest content.并设置好最新发布提醒哦
  • 2021-08-30身处险境能给激发你的超能力吗?问题:身处险境能激发你的超能力吗?QQs: Can danger give you super strength? 你可能听过这种版本的故事:孩子被困在车下You might’ve heard some version of this story before: A kid is trapped under a car, 恐慌中的母亲举起了汽车 使孩子转危为安and, in a panic, his mom somehow lifts the car up to get him to safety. 这听起来就像电影里的桥段 但它确实发生了!This sounds like something straight out of a movie, but it actually does happen! 所以危急关头到底会发生什么呢?So what really goes on in these life-threatening moments? 真的有人能爆发出超人的力量吗?Can anyone summon superhuman strength? 哦 可能吧Well, kind of. 在极端环境下 某些生物学变化会让你如获神助Some biological changes can give you a boost in extreme situations, 但是存在身体方面的限制but there’s a limit to what your body can do. 当你感到压力或恐惧时 大脑会发出信号When you’re stressed or terrified, your brain signals your adrenal gland 促使肾上腺释放皮质醇和肾上腺素 进入你的血液to release hormones like cortisol and adrenaline into your bloodstream. 皮质醇能增加血液中葡萄糖的含量Cortisol can increase the amount of glucose in your blood, 肾上腺素可以提高呼吸频率和心率 往你的身体里 包括你的肌肉and adrenaline can pump up your breathing and heart rate to shuttle more oxygen around your body, 输送更多的氧气including to your muscles. 这会让你充满能量And this can give you an energy boost! 还有证据表明 处于压力下 你的大脑会释放一种叫“内源性大麻素”的化学物质There’s also some evidence that your brain releases chemicals called endocannabinoids it is when you’re under stress, 它可以减轻你的痛苦which can reduce the pain you feel. 目前 科学家不能在实验室里制造高压 危险的情况来研究这一切Now, scientists can’t exactly create high-pressure, dangerous situations in a lab to study all this. 就像 你知道 让志愿者和具有攻击性的熊共处一室之类的Like, y’know, trapping a volunteer in a room with an aggressive bear or something. 所以很难理解这些化学物质会让身体达到怎样的极限So it’s hard to understand how much of an effect these chemicals have on pushing your body to its limits. 搞清楚这些极限的具体内容就更难了And figuring out what those limits are is even harder. 研究人体运动的科学家 被称为“人体运动学家”Scientists who research human body movement, called kinesiologists, 他们试图通过研究竞技运动员 来更好地了解这些限制have tried to study competitive athletes to get a better idea of these limits. 通常认为你的身体不会用尽全力It’s thought that your body doesn’t usually generate all the force it’s capable of. 部分原因是它更有效率Partially because it’s more efficient 毕竟 你拿起手机发短信时 不需要调动手臂上所有肌细胞after all, you don’t need every muscle cell in your arm to pick up your phone and send a text. 但它也是神经系统的一种保护方式But it’s also a way your nervous system makes sure you don’t injure yourself by 确保你不会由于过度用力而损伤肌肉组织pushing your muscles too hard and damaging tissues. 生死存亡之际 或者奥运会之类的高压环境下In a life-or-death situation, or a high-pressure situation like the Olympics, 你的大脑似乎决定莽撞行事your brain seems to throw caution to the wind. 应激反应会让你的身体消耗更多能量And stress responses cause your body to use more energy. 但是 切记你自己的身体极限:如果你状态良好时能举起50公斤Still, it’s important to remember your body has its limits: If you can only lift 50 kilograms on a good day, 那么无论如何你可能都举不起两吨重的汽车you probably can’t pick up a 2000-kilogram car no matter what. 另外 这些轰动的新闻可能有几分误导Plus, those sensational news stories can be kind of misleading. 当然啦 或许确实有人举车救子Sure, maybe someone did pick up a car to save their kid, 但他们可能不会“美国队长”一样轻而易举but they probably didn’t deadlift the whole thing like Captain America. 他们可能只是举起了一端 这并不是太重好吗They probably just lifted one end, which isn’t nearly as heavy. 所以对于时不时出现的超能力事件 我们得分清科学和科幻小说的区别So while there’s some evidence for bouts of super strength, we’ve still got to separate science from science fiction. 所以 你不要学超人 用血肉之躯挡火车So… probably don’t try to stop a train like Superman or anything. 感谢提问 特别鸣谢“众筹网站”的所有赞助人Thanks for asking, and thanks especially to all of our patrons on Patreon! 如果你想为我们提供此类素材 请登录 patreon.com/scishowIf you’d like to help us keep making episodes like this, you can go to patreon.com/scishow. 不要忘记在YouTube上订阅我们 youtube.com/scishowAnd don’t forget to go to youtube.com/scishow and subscribe!
  • 2021-08-30强度最高的材料周一 《物理评论快报》On Monday, a paper came out 刊发了一篇关于in the journal Physical Review Letters 宇宙中强度最大的材料的论文that describes what may be the strongest material in the universe. 它被称为核团It’s called nuclear pasta. 存于中子星中It’s found inside neutron stars: 中子星是由 恒星在超新星爆炸后剩下的体积超大the supermassive, dense remains of stars 密度超大的残骸形成的that have gone supernova. 事实上 它们主要由中子构成They are, in fact, made mostly of neutrons. 我们知道核团已经有一段时间了We’ve known about nuclear pasta for a while, 直到现在我们才搞清楚它的性质but we haven’t really understood its properties until now. 虽然它不会成为下一代建筑材料And while it probably won’t be the next big building material, 但是它可以让天文学家们了解中子星的行为it could help astronomers understand how neutron stars behave. 总的来说 中子星是非常超乎我们的想象的东西In general, neutron stars are pretty wildobjects! 因此 它们的内部结构也超出我们的想象And so as a result, their anatomy is alsopretty wild. 举个例子 就在上世纪七十年代初For one, they have brittle crusts, 中子星被发现后不久 我们就知道了which we’ve known about since the early 1970s, 它们有脆弱的外壳shortly after these stars were discovered. 外壳由中子构成The crust is formed by neutrons that are forced 这些中子被中子星的极端巨大的引力拉入晶格中into a crystal lattice by the star’s extreme gravity. 这种脆性的一个很有意思的特性就是A pretty cool consequence of that brittleness is 在足够的拉力下外壳会破裂that the crusts break if put under enough strain. 外壳破裂会引起各种现象And crust breaking can cause all kinds ofbehavior, 比如会引起转速增加和磁暴like an increase in rotational speed, and magnetic outbursts. 上世纪80年代有人提出Just beneath that outer crust lies the nuclear pasta, 核团就位于外壳下面which was first proposed in the 1980s. 核团这种材料是由恒星的中子和幸存的质子This material is formed when, at high pressures, 在高压下被剧烈压缩而形成的the star’s neutrons and any surviving protons are compressed so much 它们形成了非常奇特的结构that they start organizingthemselves into some really odd structures. 举个例子 这种长线状的称为意大利面For example, they form these long strings, called spaghetti, 还有这些板状的称为千层面and these board-like shapes, called lasagna. 需要声明 这些都是专业术语And for the record, those are both the technical terms! 科学家们真伟大Scientists are great. 在很长一段时间 尽管我们For a long time, though, we’ve 确实不知道中子星具有核团really had no idea what it meant for 意味着什么neutron stars to have nuclear pasta. 除了它奇怪的外形和大体组成Apart from the weird shapes and the general composition, 我们对它的特征了解甚少 比如we didn’t know much about its characteristics. Like, 如果外壳易碎 核团也是易碎吗if the crust can break, can the pasta? 为了弄清楚In an effort to figure out 壳下面发生了什么what was going on down there, 一只由麦吉尔大学 印第安纳大学以及加州理工大学的成员组成的团队a team from McGill University, Indiana University, and Caltech 借助超级计算机来模拟这种材料ran the largest supercomputer simulations of this material. 他们进行了各种各样的伸展和拉力测试They tested it under all kinds of stretching and strain, 为了能够破坏它trying to get it to break. 模拟结果显示它需要非常大的拉力才能弄破And it turns out it needed a lot of strain. Like, 比其他所有材料都要大more than it would take to snap anyother material, 这就让它很有可能成为宇宙中最强的材料making it potentially the strongest stuff in the universe. 核团层也有可能影响到上面的壳的破裂过程This pasta layer might also influence how the crust above it breaks. 这意味着 当天文学家That means that, when astronomers get data 从中子星的壳获得数据from a neutron star’s crust, 他们就很有可能推测出they might be able to extrapolate what’s going 壳下面的核团内发生了什么on in the pasta below! 当然这只是目前所做的Of course, this is the only simulation 模拟的结果of its kind that has been done so far, 因此 随着科学家继续相似的模拟 以后会有更多的新闻出现so there should be more news to come as scientists perform similar tests. 在本月早些时候的其他新闻中In other news, earlier this month, 科学家发现他们观测到物质落入黑洞中scientists reported that they observed matter falling into a black hole! Now, 落入黑洞中 这没什么大不了的 黑洞就是这样的运转的that in itself isn’t remarkable, that’show black holes work. 黑洞都会这样That’s kind of their deal. 但是研究发现物质以一个非常奇特的角度移动But these observations show matter moving at a really weird angle, 而且超级快and super fast. 这就成了新闻And that’s what makes this news! 物质聚集在黑洞周围的一个巨大的吸积盘中Matter collects around black holes in massive accretion disks, 吸积盘最深处的物质有时会被吸入黑洞中where the innermost matter can sometimes fall in. 我们所有的关于黑洞的模型All our models of black holes, 以及我们所有的关于黑洞如何吞噬物体的知识and basically all our understanding of how they gobble up stuff, 都假设它们的吸积盘没有一点倾斜assume that their accretion disks orbit with no tilt. 它们如同许多非常大的环平行于黑洞的赤道They’re like big rings parallel to the hole’sequator. Except, 当然这种假设现实中并不一定对there’s no physical reason thatneeds to be true. 吸积盘可以朝着任何方向Accretion disks could have any orientation. 我们过去并不曾看到一个黑洞的吸积盘We had just never seen a black hole behaving 不平行于自己的赤道 但现在我们发现了like its disk wasn’t parallel, until now. 在这个新的研究中In this new study, 刊登在皇家天文学会月刊上published in the Monthly Notices of the Royal Astronomical Society, 一个团队研究了一个离我们10亿光年远的a team studied a black hole at the center 处于银河系中心的黑洞of a galaxy almost a billion light-years away. 他们使用了欧洲航天局的XMM-牛顿望远镜的数据They used data from the European Space Agency’sXMM-Newton telescope: 这个太空望远镜主要利用X射线观测a space telescope that mainly observes things using X-rays, 而黑洞就会放射出巨量的X射线which black holes emit tons of. Specifically, 团队正在寻找某种元素的痕迹the group was looking for thefingerprints of certain elements. 这些痕迹就是光谱上的一些条形图案These fingerprints appear as patterns of linesin an emission spectrum, 图案上的每一条线都与某些元素发出特定波长的光有关and each line is associated with an element emitting specific wavelengths of light. 如果一些元素的图案相较于正常图案在波长上有偏移If an element’s pattern appears shifted from its usual wavelengths, 这意味着它们在移动that likely means it’s moving. 科学家可以借助这些偏移来计算物体的移动速度And scientists can use that difference to calculate the speed of the material. 在上面的例子中In this case, 落入黑洞的物体的移动速度大概是光速的三成the stuff falling into the black hole was moving around 30% the speed of light. 如果你觉得这速度非常快 那就对了And if you think that’s fast, you are totally correct. 这比我们通常看到的物质的移动速度It’s significantly faster than what we usually see 要快得多得多from this kind of matter. 比较奇怪的是What was maybe stranger, though, 物体似乎径直掉到黑洞is that this stuff appeared to be falling directly onto the black hole, 并不像我们通常看到的螺旋着掉入not spiraling inward from a disk like we usually see. 根据前面的模拟 结果显示Turns out, based on earlier simulations, 如果黑洞有着倾斜的吸积盘this is exactly what you would expect 就能看到前面所说的状况if the black hole had a tilted disk. 看 吸积盘的倾斜会引起一定程度的不稳定See, disk tilting can cause some instability, 吸积盘的大块物质会破裂并与其它物质分离and chunks of the accretion disk can break off and separate from the rest. 这些大块物质相互碰撞并抵消彼此And those chunks can collide and cancel out some 一部分的转速of each other’s rotation. 因此 不再旋转And without all the spinning, 物质被径直拉入黑洞 速度比正常快得多the matter is pulled directly into the black hole way faster than normal. 多亏了模拟Thanks to simulations, 我们可以认为称为“混沌吸积”的现象we’d thought that this so-called chaotic accretion might 在超大的黑洞中或许很常见be pretty common for supermassive black holes, 但是我们过去从未看到过but we’d never seen it happening. 吸积现象毕竟很简单After all, accretion events are pretty brief, 因此我们需要在对的时间so we’d have to catch a black hole 发现对的黑洞才能观测到at just the right moment. 但是现在 似乎我们终于做到了But now, it looks like we’ve finally done it! 当然我们必须Of course we’ll have 做更多的研究来确认结果to do more studies to confirm these results, 但这是在黑洞研究领域前进的一大步but this is a big step forward in black hole research. 当我们发现And it’s always kind 预测似乎是正确的 这件事非常让人开心of nice when our simulations seem to be right. 感谢收看本集《科学秀》太空新闻Thanks for watching this episode of SciShow Space News, 特别感谢Patreon上的赞助者们especially to our patrons on Patreon! 你们帮助我们的团队获得最新的论文和You help our team get access to the latest papers as well 影片以及这么酷的视频as film and edit all this cool research, 没有你们 我们做不到这些and we couldn’t do it without you. 如果你愿意帮助我们持续做出像本集这样的更多节目If you’d like to help us keep making episodes like this one, 可以访问Patreon.com/scishowyou can go to patreon.com/scishow.
  • 2021-08-30动物能预测地震吗?In 2011, about three weeks before a magnitude-7 earthquake hit Peru,2011年 在秘鲁7级地震发生约三周前 mammals and birds reportedly started clearing out of a national park in the Andes.报道显示 安第斯山脉的国家公园里 哺乳动物和鸟类开始不断逃离 You’ve probably heard stories like this before,你之前很有可能听过这样的故事 about animals that seem to somehow sense an earthquake coming.故事中 动物似乎以某种方式预感到了地震来临 Unfortunately, a 2018 review of more than 700 of these reports found that但不幸的是 在2018年 对700多个此类报道的调查发现 most of them were just anecdotes or single observations;这些故事大多只是传闻或者单次观察结果 they couldn’t really be backed up scientifically.无法得到科学的证实 So recently, different groups of researchers have been trying所以近期 不同的研究小组们正努力尝试 to get to the bottom of this claim for real.找出事情的真相 They’ve been trying to figure out研究者们试图弄清楚 if there really are changes in animal behavior before an earthquake地震前动物的行为是否真的会发生变化 and what could possibly explain them.以及导致这些变化的可能原因 Now, you might think, given the hundreds of times people have reported你可能认为 既然人们上百次声称 that animals were behaving oddly before an earthquake,动物在地震前表现异常 there must be something to it.那么其中必有原因 But the problem is, humans are pattern-finding machines但问题是 人类总倾向于寻找模式 and we’re also prone to a psychological phenomenon known as hindsight bias并且容易形成“后视偏差”的心理现象 where we think things that happened make sense after they happened but not beforehand.人们会在事后而非事前认为事情就该如此 We kind of can’t trust our memories.我们的记忆是不太可靠的 So, instead of looking back after an earthquake happens因而 与其在地震发生后 and trying to remember what animals were doing,试图回想动物的行为 it’s better to track animal behavior over a long period of time.不如对动物行为进行长期追踪 That way, when an earthquake happens,这样的话 当有地震发生 we can use data to compare animal behavior before and after.我们可以利用数据比较动物在地震发生前后的行为 And in a few cases, scientists have actually been able to do that.在一些研究中 科学家们确实已经能这样做 For example, in 2014, researchers at a farm in Japan例如 在2014年 研究者们在日本的农场 tracked the amount of milk a few dozen cows were making each day.跟踪记录几十头奶牛每天的产奶量 which might sound like a weird metric,这可能听起来是个奇怪的度量方式 but since most farm animals get milked at least once a day,但因为农场上大多数农场动物每天至少被挤奶一次 it was an easy way to monitor their behavior.这是个跟踪调查它们行为的简便方法 And the study found that, on average,这项研究发现 平均来看 cows produced less milk in the three weeks before an earthquake.地震发生前三周 奶牛的产奶量下降 Authors could not explain why that was happening,研究者们无法解释这一现象 but it wasn’t the only study that measured a change但这也不是唯一一个 in the behavior of farm animals before a quake.测量地震前农场动物行为变化的研究 A couple years later, in Italy, researchers in a separate study几年后 在意大利的另一项研究中 mounted accelerometers on a farm’s cows, sheep, and dogs研究者在农场的奶牛 羊和狗身上安装了加速度计 to track their movements over a few months between 2016 and 2017.追踪记录它们在2016至2017年几个月的行动 They basically put fitbits on them.他们就是在动物身上安装了Fitbit And the data showed that about five hours before a quake hit,数据显示 地震来临前约5小时 the animals’ activity patterns did change significantly.动物的行为模式的确发生了明显变化 Not only that, but the closer they were to the earthquake, the earlier their behavior changed不仅如此 距离地震发生地越近 它们的行为变化就越早 possibly because whatever signals they were detecting were stronger.可能因为它们探测到的某种信号要更强 The results were interesting for two reasons:从两个方面看 这项研究发现很有意思 First, they suggested that it might be possible to set up首先 它显示出这样一种可能 some kind of early warning system for earthquakes using—of all things—farm animals in different locations.利用不同地方农场上的动物已建立某种地震预警系统 But second, they showed that it wasn’t enough just to track a single species—其次 结果表明只追踪一种动物还不够 a good prediction required data from multiple animals好的预测需要多种动物的数据 that captured how they interacted with each other.这些数据能显示出动物行为间的联系 And soon, we’re actually going to have a lot more data like that.不久后 我们会有更多类似的数据 At the beginning of 2020, scientists from Germany and Russia2020年初 德国和俄罗斯的科学家们 launched a project called Icarus开展了名为Icarus的项目 that tracks the movement of thousands of birds, mammals, and insects across the globe.追踪全球数以千计的鸟类 哺乳动物和昆虫的行为 Rather than just looking at what one animal or a small group of animals is doing,项目并非仅关注一只或一小群动物的行为 the idea behind Icarus is to use computer algorithms to analyze big patterns of movement.而是旨在利用计算机算法分析总体行为模式 To do this, researchers plan to tag thousands of animals with small transmitters因而 研究者们计划在数千只动物身上安装小型发射器 that regularly send information on their location, activity, and local weather conditions发射器定期将它们的位置 活动和当地天气信息 to an antenna mounted on the International Space Station.发送至安装于国际空间站的天线 It is an enormous project.这是个巨型项目 And right now, it’s still in its test phase,目前项目还在试验阶段 but the goal is that, by the end of 2020,但目标是 到2020年结束前 researchers will be able to start gathering data and seeing how well it can be used研究者们能开始收集数据并检验其使用效果 to predict earthquakes and other natural events, like volcanic eruptions.即预测地震和诸如火山爆发等自然事件的效果 All these findings are pretty exciting,所有这些研究发现都很让人兴奋 and recent advances in things like artificial intelligence and satellite technology人工智能 卫星技术等科技的最新进展 have made these sorts of studies easier.让进行这类研究变得更加容易 But despite all of the evidence that尽管目前已有一些证据表明 at least some animals may be able to sense earthquakes well before they happen,至少有些动物或许能预知地震发生 we still don’t know how they’ re doing it.我们仍不清楚这些动物是如何做到的 Some scientists hypothesize that animals might be sensing vibrations in the Earth一些科学家假设动物可能会通过地震前地壳的运动 from movements in the crust right before a quake,感知到地球的震动 but there’s no strong evidence for that.但目前没有强有力的证据证明这一点 However, it’s also possible that animals are picking up on other environmental events不过 也有可能是动物感知到了 that are triggered by that movement in the crust.由这种地壳运动引发的其他环境事件 For example, the air can become electrically charged比如 空气会变得带电 as the squeezing and shifting of the Earth break chemical bonds in minerals,因为地球的挤压和变化导致矿物质中的化学键断裂 releasing charged atoms into the air.将带电原子释放到空气中 Some animals may be able to pick up on that change in the air itself.有些动物或许能感知到这类空气本身的变化 Those charged atoms can also dissolve into water, turning the water acidic.带电的原子也能溶于水 让水具酸性 And we know that, for instance, amphibians are super sensitive to changes in water chemistry比如 我们知道两栖动物对水化学成分的变化极为敏感 because their skin is permeable,因为它们的皮肤是透水的 which could explain why a whole bunch of toads fled their regular breeding pond这或许能解释 为什么在2009年意大利拉奎拉发生地震5天前 five days before the 2009 earthquake in L’Aquila, Italy.一群蟾蜍逃离了它们日常进行繁殖的池塘 Scientists who observed this behavior didn’t measure the water acidity,观察到这一现象的科学家并未测量水体酸度 so we don’t know for sure.所以我们也不是很确定 But at least it’s plausible.但至少听起来有道理 And as we learn more about how animals behave around earthquakes当我们对地震发生前后动物的行为 and how they might detect the early signals of them以及它们如何可能探测到地震早期信号的了解越来越多 we may be able to better protect ourselves from the disasters they cause,我们或许能更好保护自己 免受地震灾难的伤害 whether it’s by setting up a network of farm animals不管是通过将农场动物的行为联系起来 or building sensors that mimic certain animals’ abilities,还是开发能模仿特定动物本领的传感器 perhaps we can learn from them how to predict earthquakes on our own.或许我们能向动物学习如何自己预测地震 To learn more about how scientists study earthquakes,如果想更多了解科学家如何研究地震 you can watch our episode on earthquake science and the disaster that created it.可以收看我们介绍地震科学及引发地震的灾害的视频 And, as always, thank you for watching SciShow!跟往常一样 感谢你收看《科学秀》!
  • 2021-08-30怎样让手机电池寿命更长?很多日常生活中使用的设备都要用到电池So many of the devices we use every day have batteries 似乎大家都会有一些能使电池使用寿命延长的方法and it seems like everyone has their own rituals for making them last 有人把电池放在冰箱里Some people store them in the fridge 有人在电池充满后就马上拔掉电源or unplug as soon as the battery is charged 有的甚至坚持到电池没电时才充电or even insist on only charging when the battery is on the brink of dying. 但是当你给手机和手提电脑之类的设备充电时But when it comes to charging the batteries in things like your phone and laptop, 会发现以上大部分方法都没有显著效果it turns out that many of these strategies don’t do very much. 事实上 有些还会适得其反And some are actually counter productive. 电池的放电原理是电子在两个电极之间的流动Batteries work using electrons that try to flow between electrodes. 但是电子在电池内部的移动受到电解质的阻碍But they’re blocked by an electrolyte, 只有当电池两极被外部电线连接时才会产生电流which only lets charges flow when the two sides are directly connected by wires. 一旦所有的电子都流向正极Once all the electrons have reached the positive electrode, 电池则放电完毕 电量耗尽the battery is considered discharged, meaning it’s out of power. 对电池重新充电涉及到一个过程Recharging the battery just involves pushing those electrons 即通过外部的能量使电子重新回到负极由此电池得以再次放电back onto the negative electrode to reset the whole process. 随着电解质的消耗和电极的钝化All rechargeable batteries lose the ability to hold charge over time 所有可充电电池都将逐渐失去储存电能的能力as the electrolyte breaks down and the pieces wear out. 但电池电极的制作材料But what those pieces are made of 很大程度上决定了让电池寿命更久的方法determines a lot about how to make a battery last as long as possible. 你听到的很多关于延长电池寿命的小窍门A lot of those battery life myths you might hear 仅适用于镍镉和镍氢电池apply to nickel-cadmium and nickel-metal hydride batteries. 它们常用于电视遥控器中The kind you might have in your TV remote. 由于在这种电池里自由电子通过化学反应产生With those, because of the chemical reaction that produces the electrons, 在对其充电前应该完全放电it really is better to let them run all the way down before recharging them, 而充满电后应立即停止充电and to stop charging pretty much as soon as they’re fully charged. 否则会在电池极板上产生许多晶体 导致电池损坏Otherwise, crystals can form on the electrolyte and the batteries can break 或者造成电池容量损失or at least not hold as much charge as they should. 但如今大多数便携式设备 如手机和笔记本电脑But most portable devices these days, like your phone and your laptop, 使用的锂离子电池其工作原理不同use lithium-ion batteries which work differently. 过度充电确实会损坏锂离子电池Lithium-ion batteries do get damaged if they’re overcharged 但电池和充电器通常拥有自动在过度充电前停止充电的功能but the batteries and chargers are usually designed to stop charging before that happens. 因此您无需考虑在手机或笔记本电脑充电后立即拔下电源插头的问题So you don’t have to worry about unplugging your phone or laptop as soon as it’s charged. 并且等到锂离子电池电量即将用完再充电的电池And waiting until lithium-ion batteries are close to dead before charging them 实际上其寿命比放电深度达到70%就充电的电池寿命短5倍can actually make their lives up to 5 times shorter than always charging before they dip below 70%. 充电前电量越高 电池寿命越长The higher the charge before you plug in, the longer the battery will last. 因此 如果想要一个指标With that said, if you have something that tells you 来衡量电池剩余使用时间而不只是可用电量的百分比how much time you have left on your battery, not just the percentage, 你应该每个月进行一次完全放电帮助电脑重新校正电池总使用时间的估计值you should fully discarge it about once a month to help the computer recalibrate its estimate. 但是影响电池寿命的最大因素是温度But the biggest thing that affects all batteries is temperature. 温度越高 电化学反应越快Electrochemical reactions happen faster when it’s hotter. 所以电池在持续受热的情况下会快速老化So batteries do break down faster in prolonged heat. 但这并不意味着你应该把电池储存在冰箱中But that doesn’t mean you should store your batteries in the freezer. 冰箱里的空气或者用来放进冰箱的装电池的袋子里的空气The air in the freezer, or in the bag with batteries in it you put in the freezer 含有大量水蒸气 能快速依附在介质上结晶成冰has plenty of water vapor just waiting for a place to crystallize into ice. 没人想要一个湿漉 结冰的电池吧And you really, really don’t want wet, icy batteries. 所以如果想要手机或笔记本电脑的电池寿命更长So if you want your phone and laptop batteries to last, 应该尽可能让它们多充电keep them plugged in as much as possible. 不管你用的是哪种电池And no matter what kinds of batteries you’re storing, 储存的时候放在抽屉里就行了they’ll be just fine if you stick them in a drawer. 感谢来自Patreon的用户Dorian提出的这个问题Thanks to Patreon patron Dorian for asking this question 感谢在Patroen上不断为大家提供解答的所有用户and thanks to all of our patrons who keep these answers coming. 如果你想提交一个问题供别人解答 只需访问patreon.com/scishowIf you’d like to submit a question to be answered, just go to patreon.com/scishow. 别忘了去youtube.com/scishow观看和订阅我们的视频And don’t forget to go to youtube.com/scishow and subscribe.
  • 2021-08-30为什么水果会变面?快问快答:为什么水果会变面? Nearly everyone knows the sadness of biting into a fresh piece of fruit看似新鲜的水果一口咬下去 却又面又干 only to find the inside is dry and mealy.这种让人难过的事 大家应该都经历过 It happens to lots of produce:很多水果都会这样 peaches, watermelons, tomatoes, you name it.桃子 西瓜 西红柿等等 无一幸免 Some of the worst offenders are apples,其中最为严重的要数苹果 like those shiny Red Delicious that are beautiful on the outside比如红蛇果光鲜亮丽其外 and all grainy when you take a bite.咬一口发现败絮其中 But these fruits aren’t inherently terrible.但这些水果不是本来就很难吃 They can start off yummy, and become grainy.是刚开始十分甘甜美味 慢慢变得粗糙无味 And a lot of the problem has to do with the way they’re stored.这大多是储藏方式出了问题 When ripe apples are stored at cool temperatures,将熟透的苹果储存在较低温度下 like inside your fridge,比如冰箱里时 the cells making up the flesh of the fruit unstick from one another.构成果肉的细胞开始彼此分离 But the tough outer walls of these cells stay strong,但每个细胞外侧较硬的细胞壁依旧坚韧 so when you take a bite,你咬下一口时 they don’t break apart and release any juice.细胞不会破裂 释放果汁 So instead of a burst of flavor, you just get that mealy texture.所以你尝到的口感是面的 而不是香味迸发 That gets worse as the apple dries out.而苹果变干后 情况会更糟 Without moisture, the cells shrivel—苹果失去水分后 细胞缩水 and biting into those shriveled cells is like trying to pop a deflated balloon.咬下去的感觉就像试图扎破一个瘪掉的气球 The cells are less likely to burst and release their flavor.细胞不容易破裂 释放苹果香味 And the more mature an apple is, the more it dries out.而且苹果越熟 越容易变干 Plus, the cold air inside a refrigerator speeds up the drying process,外加冰箱里的冷气加速了变干的过程 since it holds less moisture than warmer air.因为相较热空气 冷空气里含水量更少 So research suggests that if you want to save an apple for a few weeks,所以有研究提出 如果一个苹果想要保存几星期 your best bet is to pop it in the fridge right away,做好的办法是在苹果变得过熟之前 before it becomes /too/ mature.尽快放进冰箱 But the same rule doesn’t apply to all potentially-mealy fruits.但是这条建议并不适用于所有可能会变面的水果 Soft fruits, like peaches and nectarines,偏软的水果 如桃子和油桃 can become mealy if you refrigerate them /too soon/.过早放入冰箱反而容易变面 That’s because their mealy texture is tied to因为与它们变面有关的 the breakdown of a substance called pectin.是果胶这种物质的溶解 Pectin is a carbohydrate in cell walls水果成熟时会生成果胶 that fruit generates as it ripens.这是细胞壁中的一种碳水化合物 It strengthens cell walls and makes them stick together.能强化细胞壁 使它们紧密连接在一起 But pectin can dissolve in water.但是果胶可溶于水 And over time, as it dissolves,随着时间的推移 果胶慢慢溶解 the cell walls lose their strength.细胞壁变得不再强韧 In some fruits, pectin doesn’t /just/ dissolve, either—而在一些水果中 果胶并不只是溶解 it also gets broken into pieces by enzymes.它还会被酶分解成小块 And that’s a good thing. Under normal conditions,这是好事 在正常情况下 the cell walls weaken through these processes,水果细胞壁在上述过程后软化 and the fruit becomes nice and soft.使水果变得柔软美味 When you bite into it,一口咬下 the cell walls burst and release their juice just like a proper fruit.细胞壁破裂流出果汁 这是水果的最佳状态 But as soon as you stick these fruits in the fridge,而一旦你把这些水果放进冰箱 that natural process starts to veer off track.自然的成熟流程开始脱轨 In general, low temperatures slow down chemical reactions,简单来说 低温放慢了化学反应 so if you keep fruit cold,所以如果将水果冷藏 its pectin molecules break down less.果胶溶解程度变低 And /that/ means the cell walls hold up when you bite into them,这意味着 一口咬下 细胞壁还是完整的 so whole cells break apart, rather than bursting.细胞之间完整地分离 而不是破裂 And you get a sad, mealy mouthful.满口都是面软水果 太难过了 But not all fruits will come out of the fridge equally pathetic.但不是所有水果从冰箱里拿出来都不好吃 Different kinds have different compounds attached to the pectin molecule,不同的水果的果胶分子构成不同 so they often ripen differently.它们的成熟流程通常也不同 And as a result, they /also/ react differently to refrigeration.因此 水果冷藏后 结果是不一样的 Still, as a general rule,不过 有个基本规律 fruits that continue to soften after they’re harvested—像桃子 油桃 哈密瓜和西红柿这类 like peaches, nectarines, cantaloupe, and tomatoes—采摘收割后会继续变软的水果 should only be refrigerated /after/ they’re fully ripened如果你不想吃到口感很差的面软水果 if you want to avoid that gross, grainy texture.那一定要在其熟透后再放进冰箱 Unfortunately,可惜的是 you can’t always know what happened to your fruit before it got to the store.很多时候只有在储藏后 你才知道水果会变什么样 And from the outside,而且从外表看 it’s impossible to tell which fruit already has a mealy texture.无法判断哪个水果已经变面了 But you can make sure it’s not your fault但是学会在合适的时候储藏 that it becomes mealy by storing it at the right time.水果变面就不是你的错 Thanks for watching this episode of SciShow!感谢收看本期《科学秀》! If you liked this episode如果你喜欢本期视频 and you want to learn about another reason we end up with disappointing fruit,并且想了解水果变差的另一个原因 you might be interested in this video about why apples turn brown.你或许会对《为什么苹果会变褐色》这个视频感兴趣
  • 2021-08-30超级骨骼!相信吗?在你我的身体里都有这样一些东西Believe it or not, there’s something a lot like this inside of you and inside me, too! 那就是骨骼!It’s a skeleton! 你也许在博物馆中看到过——比如恐龙的骨骼 或者You may have seen skeletons in a museum — like the ones they have of dinosaurs — or maybe 塑料人体骨骼模型plastic models of human skeletons, like this. 甚至你在好莱坞电信中看到过会跳舞的人影骨架Maybe you’ve even seen dancing skeletons around Halloween. 但是你知道你的骨架很重要 而且又酷又强大吗?But do you know how important, and cool, and powerful your skeleton really is? 让我们从骨头如何帮助你运动 不同的Let’s get to know your bones — from how they help you move, to the different 骨头类型和他们承担的特殊工作来了解他们kinds of bones you have, and even a super special job they have to do! 开始吧Let’s get started! 骨骼最重要的工作之一当然就是支撑你的身体One of a skeleton’s super important jobs is, of course, to hold your body up! 你的肌肉虽然很强壮 但是需要骨骼来支撑它 如果没有骨骼Your muscles are strong, but they need a frame, something to hold on to. Without a skeleton, 你会垮成一摊 不会成为现在有完整外形的你you’d be all loosey goosey, and you wouldn’t be shaped like …you! 当然 没有肌肉的话 你的骨骼也只是一堆骨头And it goes both ways! Without your muscles, your skeleton would just be a pile of bones. 而且只有通过收缩或舒张肌肉才能控制你的骨头It’s only by squeezing and relaxing your muscles that you’re able to move your bones 运动around. 还记得会跳舞的人体骨架吗?那只能是假的——因为没有So that silly dancing Halloween skeleton? It’s just pretend — because it doesn’t 肌肉包被have muscles! 你的骨头很坚实 因此可以支撑住你的体重So, your bones are hard enough to hold the weight of the rest of your body. 而且它们可以像盾甲一样包围保护着But they’re also hard enough to act like a protective shield around your soft, squishy 你的器官organs. 比如你的肋骨 它们保护你的心和肺 让你在被熊抱的时候Your ribs, for example, are bones that protect your lungs and heart so that even when you 不会挤压到肋骨里的器官get a great big bear hug, your insides don’t get squeezed too! 再者 你身体里有一类最大 最长And speaking of strong–the strongest bone in your body is also the biggest, the longest 最重的骨头and the heaviest one you have. 它处于你的臀部到你的膝盖之间 叫做股骨 It’s the bone that goes from your hip to your knee, called the femur! 不管是跑 跳 走 或者直立 你的体重有一大部分都压在股骨上 And that bone has to be big and strong — because when you run, jump, walk, or even just stand 所以它长得大而且很坚实still, a lot of the weight of your body falls on the femur. 你猜你身体中最小的骨头是怎样的?Now, where do you think your smallest bone might be? 它就在你的耳朵里The very smallest bone you have is actually in your ear. 这小块马蹄形骨头叫做听骨 即使是成年人This little bone, called the stapes, looks kind of like a stirrup. Even in adults, 听骨也只有一粒米粒大小it’s only about the size of a grain of rice. 但这毫不起眼的小骨头却有至关重要的作用 当声音进入耳朵时 But this tiny bone has a big job. When sounds enter your ear, they make this little bone 听骨就会振动 这些振动就是耳朵转化声音得到的 move back and forth. Those vibrations are what your ears pick up as sound. So, without 所以如果没有这一小块骨头 你就听不到声音this teeny bone, you wouldn’t be able to hear. 那现在我问你 人有多少块骨头Now I have a question, how many bones do you think we have? 幼儿骨头最多Well … it kinda depends. 虽然听起来荒诞 但你现在的骨头确实比刚刚出生时少It sounds crazy, but you have fewer bones now than when you were born! 新生婴儿有300块骨头 随着慢慢长大 Newborn babies have about 300 bones, but — by the time you’re finished growing — you’ll 就只有206块骨头have only 206. 那多余的骨头去哪了?So, where did all those extra bones go? 随着婴儿成长 有一些骨头会长在一起 或直接融合成一块大骨头Nowhere! As babies grow, some of their bones grow together, or fuse, into one bigger bone. 比如……你的头骨For example … your skull! 你坚硬的脑袋是由21块骨头融合在一起 再加上Your hard noggin is actually 21 bones that are fused together, plus one bone that always 一块单独——下颌骨组成remains separate — your jaw! 头骨一开始是一块块分开的 为你的大脑提供Your skull starts out as a bunch of separate bones, because that leaves lots of room for 足够的生长空间your brain to get bigger. 当你发育完全时 它们融合在一起为你的大脑提供And once you’re fully grown, the fused parts make an incredibly strong shield to protect 强有力的保护your precious brain. 最后一个有趣的事实是 你的骨头是活着的One final fun fact about your skeleton? Your bones … are alive! 我们一直以为骨头是死的——像博物馆里的那些Even though we often think of skeletons as not living — like the ones we see in a museum, 或者模型 但事实是骨头充盈着活细胞or in this model –your bones are full of living cells. 有一些细胞可以让骨头生长 或者修复受损的骨头Some of these cells are what make your bones grow, and repair them if they get hurt. 也有一些生存在骨腔中厚厚的海绵状物体里And other cells — which are tucked away in a thick spongy layer deep inside your bones 它们有着非常特殊的工作:造血— have a very special job: They make your blood. 是的!许多血液里的物质是在骨腔里That’s right! Most of the stuff that’s in your blood is actually made inside of your 产生的bones! 因为骨头里的细胞是活的 所以可以不断生长It’s because your bones are alive that they’re able to grow — like they are, in you, right 直至你25岁的时候 才停止生长now! And they won’t be done until you’re about 25 years old. 即使如此 骨头还在为支撑你的外形 帮助你听But even then, your bones will still be busy holding you up, helping you hear, and making 和造血而工作your blood. 博物馆的骨头很酷 好莱坞电影里的很有趣 但是不要被迷惑So bones in museums are cool, and Halloween skeletons are fun — don’t get me wrong. 没有什么比身体里活着的骨骼对我们的贡献更强大But nothing’s more scary-powerful than your own living skeleton and all the great stuff 更令人惊奇it does for you! 如果你有关于动物骨骼的有无或大小之类的疑问Do you have a question about animals with big bones, small bones, or no bones at all? 可以在家长的帮助下给我们留言或者通过写邮件发送just let us know by getting help from a parent, and leaving a comment below or emailing us 到kids@thescishow.com给我们at kids@thescishow.com. 下期见!See you next time!
  • 2021-08-28被纸划伤为何反而更痛设想你忙碌一天后 终于有时间躺在床上读本书There you are, reading a book in bed after a long day. 正当你读完某章节准备合上书时You finish the chapter and go to close the book and… 哎哟Ow! 被纸划伤了Paper cut! 划伤通常口子较小而且较浅 但因为某些原因 能让人感到相当痛Paper cuts are usually small and shallow, but they do tend to hurt a lot, for a few reasons. 事实就是大多划伤都发生在你的手上There’s the fact that most paper cuts happen on your hands, since you don’t 因为你通常是不会用比如大腿来翻页的usually try to move pieces of paper with, like, your legs. 当伤口是在身体上某个一直用到的部位时You’re going to pay more attention to an injury when it’s on a body part that you 你是会倍加关注的 比如大脑关心手use all the time, your brain thinks about your hands at least 10 times more than your 是关心手臂或大腿的十倍多arms or your legs. 当然 关心伤口意味着关注着疼痛And of course, thinking about your cut means you’re focusing on the pain. 进一步来说 指尖上的疼痛 一般来说会更痛Plus, cuts on your fingertips are just more painful in general. 由于你主要是依靠手指和手去感知你周围的事物Since you mainly use your fingers and your hands to feel the world around you, they’re full 手上会有很多能对压力和温度起反应的痛觉感受器of nociceptors, pain receptors that respond to things like pressure and temperature. 纸划伤会直接损伤最外层皮肤即表皮的疼痛感受器Paper cuts directly damage the nociceptors in your outermost layer of skin, the epidermis, 以及那些把疼痛信号传递到大脑的神经束and those nerve bundles send pain signals to your brain. 手上每平方英寸的疼痛感受器要比其他部位多得多Considering your hands have more nociceptors per square inch than almost any other part 也就说得通 为什么在手上的划伤会让人感觉痛得多of your body, it makes sense that a paper cut on your hand would be much more painful 相比于在其他地方 比如说胳膊than a paper cut on, say, your arm. 而且在各种日常能划伤你的物件中 纸是最为参差不齐中的一种Plus, of the different kinds of everyday objects that could cut you, paper is one of the most jagged. 刀子一般会留下一个干净无残痕的口子A knife will generally leave a clean, residue-free cut, but dull, flexible paper will tear your 但又钝又软的纸则像一把锯把皮肤细胞撕开skin cells apart like a saw. 纸也会留下碎片和化学品Paper can also leave fragments and chemicals behind that irritate your vulnerable inner 这些东西会刺激易受损的的内层皮肤即内皮skin layer, or dermis. 即使发生很多纸划伤深度不足以伤害血管的情况Even with all that skin damage, many paper cuts aren’t deep enough to hit blood vessels, 所以几乎没有出血或是凝血的情况 其实会使情况变得更糟so there’s very little bleeding or clotting, which actually makes things worse. 没有痂来保护暴露的组织时 你所做的每件小事都能Without a scab to protect the exposed tissue, every little thing you do can stimulate pain 刺激疼痛感受器receptors. 手表面的伤需要很长时间才能痊愈And superficial hand wounds take a long time to heal. 当你用手去做事 洗碟子 弹吉他 拿杂物时When you use your hands to do things, wash dishes, play guitar, carry groceries, your 纸划伤会持续撕裂 变脏 延长痊愈时间paper cut keeps tearing and getting dirty, increasing the healing time. 于是有各种各样不同的原因综合起来令纸划伤让人更痛So there are lots of different factors that combine to make paper cuts more painful than 相对于其他引起浅口的损伤you’d otherwise expect from such a shallow cut. 手和纸的边缘就是一对冤家Hands and the edges of paper are just a bad combination. 感谢PatreonpatronsUrbanAbybos 和Elvina Lui的提问Thanks to Patreon patrons UrbanAbydos and Elvina Lui for asking, and thanks to all our 以及所有一直思考得出这些答案的所有人patrons who keep these answers coming. 如果你想要提交一个能被回复的问题 就到网站patreon.com/scishow查询If you’d like to submit a question to be answered, just go to patreon.com/scishow, 接着别忘了去youtube.com/scishow订阅哦and don’t forget to go to youtube.com/scishow and subscribe.
  • 2021-08-28不是植物也不是动物的菌类蘑菇我和吱吱刚决定午饭要吃啥Squeaks and I were just deciding what to have for lunch, 我们现在想吃:披萨!and we’re thinking: pizza! 你可能听说过一些我希望加上的表层配料You’ve probably heard of the topping that I want on mine, 但是它有点不大寻常but it’s a little out of the ordinary. 我来给你个提示I’ll give you a hint. 它含有大量的维生素和矿物质it has lots of vitamins and minerals. 但并不是一种植物But it’s not a plant, 所以不是西兰花或者辣椒 或者橄榄so it’s not broccoli or peppers or olives, 虽然这些蔬菜我都挺喜欢的though I do love all of those vegetables! 它也不是来自动物And it doesn’t come from an animal, 所以它不是腊肠或者意大利辣香肠 尽管我也喜欢这些so it’s not sausage or pepperoni, though I do like those, too! 你能猜到我想的是什么吗Can you guess what I’m thinking of? 我打算吃一些蘑菇!I’m going to have some mushrooms! 没错 蘑菇不是植物That’s right, mushrooms aren’t plants, 也不是动物and they aren’t animals, either. [吱吱][Squeaks] 蘑菇是一种真菌Mushrooms are a type of fungus! 真菌是一种完全区别于其他物种的生命体——Fungi are a whole separate kind of living thing– 既不是植物 也不是动物not plants, and not animals. 有些长得很像Some of them look a lot 那种我想放到披萨上的蘑菇like the mushrooms I’ll be having on my pizza. 但是别的一些就非常奇怪了!But others are much weirder! 这里有黑女巫的黄油There’s black witches’ butter, 那是一种果冻真菌which is a type of fungus called a jelly fungus. 我打赌你可以猜到原因I bet you can guess why. 它长得很像又厚又黑的果冻!It looks a lot like dark, thick jelly! 这是大脑蘑菇Then there’s the brain mushroom, 看起来像是……好吧 一个大脑which looks a lot like…well, a brain. 甚至还有生长在黑暗中的蘑菇!There are even mushrooms that glow in the dark! 真菌看着就像是外面长的植物Fungi might seem like plants from the outside, 因为它们大多生长在地面上because many of them grow from the ground. 但科学家们有了一些非常酷的发现But scientists have made some pretty cool discoveries 使得它们与植物相比与众不同about fungi that make them different from plants! 例如 让植物显得特别的一件事是For example, one thing that makes plants special is 它们利用阳光合成自己的食物that they make their own food out of sunlight. 那是所有植物获得食物的方式 但真菌无法做到That’s how all plants eat, but fungi can’tdo that! 相反 它们所需要的食物Instead, they have to get their food 只能从其他生命体获取 比如说我们动物from other living things, just like us animals. 这也是蘑菇能在黑暗中生长的原因——That’s also why you might see mushrooms growing in dark places– 它们可不需要阳光!they don’t need the sunlight! 但是植物不能在黑暗中生长But plants won’t grow in the dark. 并且记住这点Also, get this, 当你近距离观察真菌时when you look at a fungus really close up, 你可以看到 它们实际上you can tell that they’re actually 是由组成动物的物质组成的 而不是植物!made of some of the same stuff as animals, not plants! 但是请记住 真菌也不是动物But remember, fungi aren’t animals, either. 首先For one thing, 即使真菌不能像植物一样合成食物even though fungi have to seek out their food 而不得不寻找食物since they can’t make it themselves like plants do, 它们也不能像动物一样跑或走甚至飞行they can’t run or walk or even fly to get it like animals can. [吱吱][Squeaks] 它们是怎么获得食物的?How do they get food? 事实上 真菌就生长于它们的食物上Well, fungi actually grow right on top of theirown food. 例如 蘑菇会吃死的植物Mushrooms, for example, eat dead plants, 这也就是为什么它们长在树上或森林地面上which is why they often grow on trees or the forest floor. 随着真菌长得越来越大 它们能够吸收As fungi get bigger, they’re able to absorb, 越来越多的食物or soak up, more and more food. 在这方面 它们很特别They’re pretty special that way. 你我一样的动物When animals like you and me 需要分解食物并且将其转化为能量break down our food and turn it into energy, 而我们就在体内完成这一步we do it inside our bodies. 我们的胃会分泌特殊的胃酸Our stomachs add special stomach juices to the food 来更容易地消化食物in our bodies to break it down more easily. 真菌则用完全不同的方式消化食物Fungi digest food in a totally different way! 它们也会分泌酸液到食物上They add stomach juices to their food, too, 但它们却是直接将其分泌到要吃的食物上but they spread it right on what they’re eating, 所以食物的分解过程so the food gets broken down 是在身体外部进行 而不是内部!outside of their bodies, not on the inside! 食物被分解完后Then, after the food is broken down, 真菌就吸收掉剩下的部分the fungi just soak up what’s left over. [吱吱][Squeaks] 我同意——真菌真的很了不起!I agree–fungi are pretty awesome! 尤其是蘑菇Especially mushrooms. 但是即使很多蘑菇对你有好处But even though a lot of mushrooms are good for you, 像披萨上这一类的 我们like the ones on pizza, we definitely 绝对不要自己挑选蘑菇don’t want to go picking mushrooms ourselves 那是因为世界上有That’s because there are sooooo many different types 太多太多种类的蘑菇of mushrooms in the world, and some 而且其中的一些会让你吃出大毛病of them could make you really sick if you eat them. 它们往往会导致胃痛They can give people a stomach ache, 或者呕吐 甚至更糟or make them feel like throwing up, or much worse! 一些蘑菇是对你有害的And some of the mushrooms that are bad for you 但它们像极了那些对你有益的种类actually look a lot like mushrooms that are good for you! 所以我们把正生长的蘑菇留给专家们吧So we leave the mushroom growing to the experts 不要自己去挑选and don’t pick them ourselves. 现在我认为到了点些披萨的时候啦!Now I think it’s about time that we ordered some pizza! 谢谢观看!Thanks for joining us! 如果你想要与吱吱和我继续If you want to keep learning and having fun 学习或者是享受乐趣 请点击订阅按钮with Squeaks and me, hit the subscribe button, 不要忘了在YouTube Kids软件上了解我们and don’t forget to check us out on the YouTube Kids app. 谢谢大家 下次见 这里是FortThanks, I’ll see you next time, here at the Fort!
  • 2021-08-2810分钟了解四十亿年地球史地球自形成以来的四十五亿年间Earth has been through a lot 历经了沧海桑田in the four and a half billion years since it formed. 地球的大部分历史面貌都已被Most of Earth’s history has been shaped 板块运动带来的大陆间相互碰撞所改变by plate tectonics, where continents slide around. 与恰好绕开相反的是But instead of skirting around each other neatly, 大陆之间相互作用的方式the continents can interact in some 往往会十分地出人意料pretty unexpected ways. 大陆相聚到一起 又崩裂开来Continents come together and burst apart 中心位置的岩石却又能保持稳定while the rocks at their centers stay put. 地壳在地质构造运动和Earth’s crust is flung upward 大气的风化作用下被不断剥离by tectonics and weathered back down by the atmosphere. 多年来由此导致了诸多变化And that’s led to a lot of changes overthe years. 在地球历史的初始阶段For the earliest part of Earth’s history, 我们根本没有岩石可寻 也就是说we don’t have any rocks at all, meaning 我们无法直接进行研究we can’t study it directly. 在生命的第一段时期For the first part of its life, 这颗行星还是个火球 经常遭遇小行星撞击the planet was a molten mess, constantly bombarded by 而且不够稳定 难以保存那段历史asteroids and not stable enough to preserve much record of that time. 因此地球的所有地质史So any geological history of the Earth 都只能以大陆开始稳定之际为起点has to start when the continents started to stabilize, 差不多是30到35亿年前somewhere between 3.5 and 3 billion yearsago. 这些古老岩石上并未记载任何日期These super-old rocks don’t exactly have dates written on them, 但它们的化学转变but a quirk of chemistry 却能帮助我们判断它们的年代can tell us how old they are. 并由此产生了一个全新领域 同位素地球化学And that has led to an entire field calledisotope geochemistry. 每个原子的原子核中都有See, each atom comes with a certain number 一定数量的质子和中子of protons and neutrons in its nucleus. 不同元素的区分靠的是核中质子的数量Different elements are defined by the number of protons 因此每种元素的原子中in the nucleus, so the atoms of 都有相同数量的质子each element all have the same number of protons. 而中子的数量通常有可变的余地But there’s usually some wiggle room inthe number of neutrons. 举例来说 碳原子有六个质子For example, carbon has six protons, 而天然的碳原子可以有六到八个中子不等but natural carbon can have six, seven, or eight neutrons. 这些变体统称为同位素Those carbon variants are called isotopes, 命名原则也是依据其质子and they’re named based on how many protons 和中子的数量and neutrons they have. 因此有六个质子和六个中子的碳原子为碳12So carbon atoms with 6 protons and 6 neutrons are carbon-12, 六个质子七个中子就是碳13 以此类推6 protons and 7 neutrons makes carbon-13, and so on. 不同的同位素有不同数量的Because different isotopes have different numbers 中子 其重量也因此而异of neutrons in them, they weigh different amounts. 差别细微 却足以让地球化学家们It’s a tiny difference, but it’s enough that geochemists 区分并计算can separate them and calculate 每种同位素的数量how much of each one there is. 有些同位素会随时间衰变Some isotopes decay over time. 比如 碳14会失去一个质子Carbon-14, for example, loses a proton 衰变为氮14and turns into nitrogen-14. 开始是铀238的原子And atoms that start out as uranium-238 经过不断的衰变 最终全部decay over and over again until they eventually 变为铅206become lead-206. 我们已知这些衰变的时长Because we know how long those decaying processes take, 那么测量已衰变和未衰变的同位素数量之比the ratio of decayed isotopes to their non-decayed precursors 就可以帮助我们很好地确定某件东西的年代can give us a good estimate of an object’s age. 铀衰变为铅所需的时间十分漫长Uranium decays to lead over a very long period of time, 因此不同的铅同位素所占的比例so the ratio of different lead isotopes 是一种很有用的判定岩石年代的资源can be a very useful resource in telling the age of a rock. 这只是同位素地球化学中的一种简单方法And that’s only one of the simpler things isotope geochemistry can do. 导致同位素比例发生变化的原因Ratios of isotopes can change as a result 除了放射性 还包括各种自然进程of all sorts of natural processes, not just radioactivity. 碳同位素的比例可以显示出The ratio of carbon isotopes can show whether carbon trapped 某块矿石中的碳是否被用于光合作用in a mineral was once used for photosynthesis, 也就能判断其是否曾被用于组成生命体and therefore was part of something alive at some point. 硫同位素可以用来判断And sulfur isotopes can be used to show 某块矿石是在地球表面附近whether a mineral was formed near the surface of the Earth, 还是在更深处形成or much farther down. 同位素地球化学可以提供给我们Isotope geochemistry gives us all kinds of information 这世界上最古老岩石的各种信息about the world’s oldest rocks. 这些远古的石头又能帮我们And those ancient rocks give us a way 拼凑出大陆板块的浮沉历史to piece together the history of the continents, 包括板块运动带给它们的移变including the way plate tectonics has shifted them around. 板块构造的存在是因为地球像洋葱一样有着分层Plate tectonics are a thing because Earth, like an onion, has layers. 有些分层是固态 有些则更有流动性Some layers are solid and some are more fluid. 最外层当然是固态The outermost layer is, obviously, solid. 即岩石圈That’s the lithosphere, 它构成了托起大陆与海洋的底盘which makes up the plates that hold the continents and oceans. 向下一层则有些液体特征Underneath that is a layer that is little bit more liquid-y, 岩石就漂在这上面where rock is flowing. 该层的运动推动着大陆That movement pushes the continents around, 也就造成了板块运动which gives us plate tectonics. 但是有一个问题:并非圈圈生而平等But there’s a catch: not all lithosphereis created equal. 支撑大陆的地壳The crust that holds up the continents is 比海洋底部的厚 密度要小thicker and less dense than the crust beneath the oceans. 大陆板块漂浮得很好The continental crust floats really well, 你可以想象一块数千千米厚的if you can imagine a slab of rock thousands 岩石平板在那漂着of kilometers across floating. 这就意味着 海洋板块与大陆板块相遇时That means, when oceanic crust and continental crust meet up, 前者容易被推到下面the oceanic crust tends to get shoved underneath 通过一种叫做俯冲作用的过程而消失and melted in a process called subduction. 大陆板块则向上仰冲The continental crust rides on top 得以幸存 有朝一日再次碰撞and survives to collide another day. 也就是说每片大陆的某些块And that means that certain chunks of every continent 都有三十亿年及以上的历史go back as much as three billion years or more. 这些超稳定的陆地块叫做稳定地块These super-stable continental chunks arecalled cratons. 它们由坚硬而又能浮动的岩石组成They’re made of tough, floaty rock 而这些岩石已经存在至少三十亿年that often hasn’t been melted by plate tectonics 在板块运动中成功逃生了for three billion years or so. 最年轻的一批存在了大约五亿年The youngest ones clock in around half a billion. 在地球还是熔岩遍地的大火球时期Back when Earth was still a liquidy mess of molten rock, 更重的元素缓慢地向地核下沉the denser elements slowly sank towards the core. 就像油会浮到水面上一样And just like oil floats on top of water, 轻的元素上浮到表面the less dense elements rose toward the surface. 所以大陆板块大多是由So continental crust is mostly made of 相对较轻的富含二氧化硅的岩石构成relatively light rocks rich in silica. 随着这些轻石头逐渐冷凝下来As these light rocks started to cool and condense, 它们会像软木塞一样they would have bobbed like a cork 在地球表面鼓起来on the surface of the planet. 这些能浮起来的小塞子会互相挤压Those little floaty corks would have bashed into each other 但不会一个俯冲到另一个下面and instead of one subducting under the other, 而是粘连到一起they would have stuck together. 一段时间后就成了大木塞了After a while, you would get bigger floaty corks. 这些大块开始稳定下来These chunks really started to stabilize 逐渐变为大陆into continents during the Archean eon, 时间大概在25到40亿年前的太古宙about 4 billion to 2.5 billion years ago. 这一时期的稳定地块构成了第一批大陆的核心Archean cratons formed the nuclei of the first continents, 且从此以后就滞留在这个状态and they’ve stuck around ever since. 地理学家们认为大多数大陆的构建Geologists think that most continent building happened 都开始在太古宙之前 而大部分形成在此阶段之后way back then and was pretty much done after that. 当然 板块运动帮助重造了很多Sure, they’ve rearranged a ton by plate tectonics, 但很多的陆地but much of the actual land is 自太古宙时期就已存在 仍是一样的the same land that existed in the Archean. 而有证据表明But some evidence suggests 有时候地球内部的轻岩石仍能浮上来that lighter rock can still bubble up from inside Earth sometimes 增添成为星星点点的陆地and add new bits and pieces. 你可能听过盘古大陆You might heard of Pangea, 就是恐龙时代存在的超大陆the supercontinent that existed around the time of the dinosaurs. 地理学家认为其只是最近一次Geologists think Pangea is only the latest supercontinent 行星撞击周期中的一个超大陆in a planetary boom and bust cycle, 这种聚成与崩裂是会频繁发生的where supercontinents assemble andbreak up every so often. 他们此对此事发生的原因不能完全确定They aren’t totally sure why this happens, 但主流的说法是but the leading hypothesis is that 这些厚重的大陆板块构成的巨大障碍those big blocks of thick continental crust 困住了底部的大量热能trap lots of heat beneath them. 最终 被困住的热量以岩浆热柱的形式Eventually, the trapped heat bubbles over in the form 喷薄而出 喷得超大陆分崩离析of magma plumes and blows the supercontinent apart, 就像慢动作下被撞开的台球一样like billiard ballsbreaking up in slow motion. 各片大陆相互分开 直到下次相遇时Then the pieces bounce around until they meet up again, 大陆板块又会粘连到一起with continental crust sticking together, 而不是发生俯冲instead of getting subducted. 这样 下一个周期又开始了And the cycle begins again. 地理学家对地球上的大陆Geologists have a pretty good understanding 一直以来的运动有着非常不错的理解of how Earth’s continents have moved around over time, 而这是基于像拼图一样对岩石进行匹配得来的which they’ve figured out by essentially matching up rocks like puzzle pieces. 板块构造学说首次被部分提出是基于Plate tectonics was first proposed in part based on 南美洲与非洲轮廓恰到好处的相互拼合how neatly South America and Africa fit together, 其暗示了它们都曾是同一片广袤大地——suggesting they were once part of 盘古大陆的一部分the same landmass–Pangea. 对更古老的超大陆的探寻也是如此Hunting for older supercontinents is like that too, 但难度系数要上升到11but with the difficulty ramped up to 11. 地理学家使用的主要工具叫做古地磁学The main tool geologists use for this is called paleomagnetism, 使用这一工具主要是基于which is based on the fact 地球磁场会规律性地发生反转that Earth’s magnetic field regularly reversesitself. 岩石在形成时When a rock forms, 其中的任何磁元any magnetic bits in it 都会与地球当时的磁场对齐will line up with Earth’s magnetic field at the time. 也就是说 含有磁性粒子的岩石That means a rock containing magnetic particles 会反映出其形成时will reflect where Earth’s magnetic field 地球磁场的指向was pointing when the rock formed. 由于磁场的反转And since the magnetic field reverses on the order 为数千年一次of thousands of years, 这就为我们探寻数十亿年来发生的事that provides a ton of data when we’re looking 提供了海量的数据at things that happened over billions of years. 利用数学 我们能十分精确地找到Using math, we can pinpoint pretty accurately 所需的岩石究竟在何处where on Earth the rock was. 大陆在这漫漫地球史中都去了哪The question of where the continents have been 仍是个颇具挑战性的问题throughout Earth’s history is a challenging puzzle, 并非轻易就能解决and one that’s far from being solved. 不过我们还是有可以使用的工具But we do have some tools that we can used to figure it out, 地理学家也有关于and geologists have some ideas about 泛大陆之前聚集成的超大陆的看法the supercontinents that assembledbefore Pangea. 我们把最开始的那个叫做乌尔大陆We call the very first continent Ur, 它是第一个由小岛屿形成的大片陆地and it was the first big bit of land to form from small islands. 乌尔大陆存在于约三十亿年前Ur goes back about three billion years, 组成它的陆地可以在今天的非洲and was made up of bits of what is now Africa, 澳大利亚和印度找到 或许还有南极Australia, India, and maybe Antarctica. 实际上 乌尔大陆在盘古大陆形成时才分裂In fact, Ur only broke up recently, when Pangeadid. 一块大陆能维持将近三十亿年A continent that can last nearly three billion 真是大陆中的佼佼者years is one heck of a continent! 一些证据指向比乌尔还要古老的大陆的存在Some evidence points to a landmass even older than Ur, 它被称为瓦巴拉大陆 能追溯到36亿年前known as Vaalbara, as far back as 3.6 billion years ago, 但关于其存在的证据还不够确凿but the evidence for its existence isn’t conclusive. 乌尔大陆最终加盟了更多新生大陆Ur was eventually joined by more brand new continents, 如北极大陆 大西洋大陆和妮娜大陆like Arctica, Atlantica, and Nena. 顺便说下 这些大陆可能名字很奇怪By the way, these continents might have odd-sounding names, 但如果你把它们拆开来看的话 你会发现but if you pick them apart you’ll realize that 它们很多都是很多单词杂糅在一起a lot of them are smashed-together words 来表示其中包含的陆块to represent the smashed-together landmasses. 举个例子 Nena这个名字Nena, for example, 就取自Northern Europe(北欧)gets its name from the first letters of 和North America(北美)这些单词的首字母Northern Europe and North America. 上述大陆都被认为All these continents are thought to have joined up 曾在大约19亿年前about 1.9 billion years ago to form the 参与组成过第一个first supercontinent that can be identified 具有几分可信度的超大陆 即哥伦比亚超大陆with some degree of confidence, called Columbia. 哥伦比亚超大陆持续到约15亿年前才分裂Columbia lasted until about 1.5 billion years ago, when it broke up. 大陆碎片分而又合The pieces then rebounded and joined up 在大约11亿年前形成了罗迪尼亚超大陆to form the supercontinent of Rodinia about 1.1 billion years ago. 在此之后 可能又After Rodinia, there may have been 短暂存在过一个叫潘诺西亚的超大陆a very short-lived supercontinent called Pannotia, 但4亿5000万年前盘古大陆的形成but things were definitely on their way to becoming Pangea 是可以确定的by 450 million years ago, 并在约2亿5000万年前达到全盛and at maximum scrunchiness around 250 millionyears ago. 然后1亿7000万年到一亿年前之间Then between 170 and 100 million years ago, 盘古大陆分裂为我们今天熟知的大陆Pangea broke up into the continents we know today. 我们正跟踪另一个超大陆We’re on track for another supercontinent 时间差不多是在2亿5000万年后in about 250 million years, give or take. 如果南北美洲继续向西漂移If North and South America continue to drift westward 横渡太平洋 它们会与俄国相遇across the Pacific, they’ll meet up with Russia 并形成阿美西亚超大陆and form the supercontinentof Amasia. 现在这些大陆之间推来搡去Now all those continents shoving each other around 对我们这个地面上的世界doesn’t come without consequences 不是没有影响的for our world on the surface. 正是这样才有了各种山——That’s actually how we get mountains– 各板块边界处常常会有造山运动the boundaries between tectonic plates often produce mountain ranges. 海洋板块俯冲到大陆板块下面时When oceanic crust is subducted under continental crust, 后者相应地被向上推起the continental crust is shoved upward to compensate. 南美洲的安第斯山脉就是个典型The Andes in South America are a good exampleof that. 当两个更富有弹性的大陆板块相遇时When two pieces of more-resilient continental crust meet up, 结果会更具戏剧性the results can be even more dramatic. 大陆板块不会向下俯冲Continental crust doesn’t tend to subduct, 所以就会有点向上折叠so instead it just kind of folds upward. 甚至于 即便基于同样的过程形成了山And even when mountains form through the same basic process, 它们互相之间they can still look hugely 还是会差异巨大different from one another. 一个关键的不同在于年龄One key difference is their age. 北美洲的阿巴拉契亚山脉The Appalachian mountains in North America 比个山丘高不了多少aren’t much more than hills at this point, 跟别的山脉比 基本就是风景秀丽 有点起伏的山坡而已basically scenic, rolling slopes compared to some other mountain ranges, 就像是亚洲的喜马拉雅山脉like the Himalayas in Asia, 这颗星球上最雄伟的山脉 同时也是珠峰所在the greatest mountain range on the planet and home to Mt. Everest. 但阿巴拉契亚曾一度高过喜马拉雅But the Appalachians were once even tallerthan the Himalayas. 二者形成的原因类似The Appalachians and the Himalayas were formedin similar ways: 喜马拉雅诞生自印度次大陆向亚洲的冲撞The Himalayas came from the Indian subcontinentcrashing into Asia. 印度必须横渡大洋来到达那里India had to cross the ocean to get there, 这也就意味着其北边的海洋部分板块meaning the oceanic crust north of it was 要俯冲到青藏高原下面subducting under the Tibetan plateau. 但这片次大陆以其厚实的稳定地块撞了上去But then the subcontinent hit, with its thick,cratonic continental crust. 印度与青藏高原直接对撞India and the Tibetan plateau crunched directly 并像手风琴一般发生了折叠into one another and folded up like an accordion. 这一切都发生在相对来说的近期All this happened relatively recently, 差不多4000万年前within the last 40 million years or so. 实际上 这一过程仍在继续In fact, it’s still happening, 喜马拉雅山脉仍在长高 尽管and the Himalayas are still growing, although that growth 风化与侵蚀作用可能与之相消might be matched by weathering and erosion. 时间足够长的话 风化作用可能会大幅地Given enough time, weathering can shrink mountain ranges 削减山脉 如同在阿巴拉契亚所发生的一样by a lot, which is what happened to the Appalachians. 阿巴拉契亚山脉形成于The Appalachian mountains formed when 盘古大陆形成时期北美与非洲板块the North American and African plates collided 之间的相互碰撞during the formation of Pangea. 那时的它可能比今天的喜马拉雅They might have been even taller and more impressive 还要高大与震撼than the Himalayas are now, 两个大陆板块奋力向前 毫不退让with two continental plates colliding and refusingto give way. 但那是将近5亿年前的事了But that was almost 500 million years ago, 5亿年足够让风雨and 500 million years is enough time for 将阿巴拉契亚消磨殆尽a lot of rain and wind to wear the Appalachiansdown. 因此 巨大的陆地相撞相离So, huge continents smash together and break apart. 一条条山脉生而复灭Mountain ranges form and wear back down. 即使我们无法在一旁看到这些事情的发生And even though we weren’t around to see those things happen, 我们仍可以通过脚下的岩石去了解这一切we can still learn about them just by studying rocks. 感谢收看本集SciShowThanks for watching this episode of SciShow, 视频由来自Patreon的赞助商赞助播出brought to you by our patrons on Patreon. 如果你想支持这个节目If you want to help support this show, 请前往patreon.com/scishowjust go to patreon.com/scishow, 同时别忘了前往youtube.com/scishow点击订阅and don’t forget to go to youtube.com/scishowand subscribe.
  • 2021-08-28真实的机器人是怎样的当想到机器人的时候 你脑海里会浮现怎样的场景呢What do you picture in your mind, when you think of … robots? 你是不是想到了一个像这样的能边走边说话的金属物体Do you think of a walking, talking piece of metal like this? 很多人都是这样想的 因为有些机器人看起来确实有些像人类A lot of people do! Because some robots really do look sort of like people… 但是 除了电影里的机器人现实生活中大部分机器人看起来并不像人类But, despite what you see in the movies, most real-life robots don’t look like us. 他们看起来可能像动物 就像这里的Squeaks或者可能是一些我们从没有见过的形状They can look like animals, like Squeaks here, or like things you’ve never even seen before. 因为工作不同 机器人的形状和大小也不尽相同Robots come in all different shapes and sizes, because they all have different jobs to do. 如果你在好奇机器人到底是什么 并且他们是干什么的And if you’re wondering what robots really are, and what they can do … 那么 你不是唯一一个You are not alone! 七岁的罗恩最近给我们发了一封邮件 问我们“什么是机器人 他们是怎么工作的”7-year-old Rowan recently emailed us to ask: “What is a robot, and how do robots work?” Squeaks说“问得好 罗恩 ”Squeaks says “Great, question, Rowan!” 机器人是设计来做一项特殊工作的机器A robot is a machine that’s designed by people to do a specific job. And the scientists 并且 设计机器人的科学家被称为机器人专家who design and build robots are called roboticists. 大部分机器人做的都是人类无法做或不想做的工作Most robots do jobs that people can’t do, or don’t want to do. 比如说有些无聊 需要反反复复做同一件事的工作If a job is kind of boring — like if it involves doing the same thing over and over — or if 又比如非常危险需要去一些很容易受伤的地方的工作a job is very dangerous — and it means going places where people could get hurt — then 那么机器人很可能代替我们做这些工作chances are, a robot has been built to do it instead! 最早的机器人是大约50年前创造的 用于帮助工厂生产汽车The very first robot was built over 50 years ago to help build cars in a factory. 直到今天 汽车制造厂仍旧依赖机器人做各种各样的工作:Today, car factories still depend on robots a lot like that one to do all kinds of jobs: 从组装零件from putting the pieces of car together 到组装完成喷漆上色to spraying them paint when they’re finished. 机器人也做各种其他的工作–像制造电脑And robots work in lots of /other/ kinds of factory jobs, too — like building computers, 甚至是包装糖果and even putting candies in their wrappers! 机器人很擅长这样的工作 因为他们不像人类Robots are good at jobs like these, because unlike humans, they’re less likely to make 当他们工作时他们犯的错误更少并且他们不需要放假 甚至不需要午休mistakes when they’re working, and they don’t go on vacation, or even lunch breaks. 除此之外 他们从不觉得厌倦 能够一直工作 一直工作 一直工作Plus, they never get bored. They can keep going, and going, and going. 这就使得机器人非常适合在夜间工作This makes nighttime jobs the perfect fit for rabots. They can do things like control 比如在我们睡觉时替我们控制城市火车city trains after dark while we get our sleep! 机器人也能在人类很难适应的地方工作Robots can also work in places that humans would have a tough time adjusting to — or 或者我们根本无法到达的地方where we could never go. 有些机器人在非常炎热的地方工作 比如火山附近There are robots that work in really hot places, like volcanoes… 还有些在非常寒冷的地方 比如深海…and really cold places like deeeep underwater in the ocean 甚至有些在非常臭的地方 比如污水处理厂….and even in really smelly places like sewage plants. 更甚至有些机器人在别的星球上为我们工作There are even robots doing jobs for us on other planets. 是的 那意味着有些机器人在太空里Yup, that means there are robots in space! 这是两个有轮子的机器人 一个叫机遇号 另一个叫勇气号There are two robots-on-wheels, named Opportunity and Curiosity, 现在正在火星上漫步 that are cruising around on Mars right now! 科学家叫他们漫游机器人 他们看起来可能像小车或是手推车Scientists call them rovers, and they might look like cars or go-carts, but they’re 但他们也是机器人 因为他们能接收来自地球的科学家的指令considered robots, too, because they get instructions from scientists here on Earth to do all kinds 去做各种重要的工作 像检测火星的空气质量 挖掘土壤 甚至钻取of important work — like studying the planet’s air, digging up soil, and even drilling into 岩石以研究其组成成分rocks to see what they’re made of! 科学家希望通过机遇号和勇气号的发现能够Scientists hope that the discoveries that are made by Opportunity and Curiosity will 帮助我们研究出把人类送上火星的方法help us figure out how we can one day send humans to Mars! 另一个叫R2的机器人被送上了国际空间站 因此成为了第一个Another robot called R2 was sent to the International Space Station, making it the first human-like 在太空的类人机器人robot in space. 即使他们并不寻常 还是有些像R2的机器人Even though they’re not very common, there are other robots, like R2, that look and act 外表和行为都有些像人类sort of like people. 他们中的一种 叫阿西莫的机器人能够做一些令人惊叹 十分像人类行为的事One of them, called ASIMO, has been built to do some amazing, lifelike things. Although 尽管至今他没去过太空 阿西莫能走路 跑步 上楼梯 甚至跳舞he hasn’t been to space—yet!—ASIMO can walk, run, climb stairs, and even dance! 类似阿西莫的智能机器人向我们展示了从约50年前创造了第一个机器人至今Robots like ASIMO show us just how far roboticists have come since they built the very first 机器人专家们取得了多么大的进步robot over 50 years ago. 可能距机器人能陪你写作业 或每天早上载着你It’ll probably be a long time before a robot can do your homework with you, or fly you 飞向学校还有很长时间 但是他们已经在很多家庭出现了to school every morning. But they’re already showing up in lot of homes, doing ordinary 做着一些非常简单的家务 像修理草坪或打扫房子而我们所需要做的仅仅是插上插头接通电源chores, like mowing the lawn or vacuuming the house. All we have to do is plug them 或按下启动按钮in or press the START button. 所以啊 谁能想象得出未来50年里的超级机器人的样子呢So, who knows what super-cool robots there will be in the next 50 years! 我已经迫不及待想看个究竟了I can’t wait to find out! 谢谢罗恩提出了一个这么有趣的问题 并且感谢你和Thanks to Rowan for asking such a fun question, and thanks to you for learning about robots 我与Squeaks一起了解机器人with Squeaks and me. 如果你有任何疑问 想了解更多信息And remember, if you have a question about anything you’d like to learn more about, 请通过爸爸妈妈的帮助让我们知道并且在下方写下评论或者发送邮件just let us know by getting help from a parent, and leaving a comment below or emailing us 到kids@thescishow.comat kids@thescishow.com. 我们下期节目再见 See you next time!
  • 2021-08-28考拉是怎么保持凉爽的?[Intro][Intro] 大家好,我是Jessi,这是儿童科学秀。这里有点儿热啊Hello, I’m Jessi and this is SciShow Kids. It’s kind of warm in here. 除非你变成一只机器鼠,不然有时你可能会觉得很热Unless you happen to be a robotic rat, you probably get hot from time to time. 我们人类和许多其他动物同样如此,而且不同的动物有不同的诀窍Us humans and lots of other animals do, too, and different animals have different tricks 保持凉爽for keeping cool. 在夏天,例如,我喜欢踢足球。比赛结束时In the summer, for example, I like to play soccer. And by the end of the game, after 在跑跑跳跳之后,我的头发和脸上都满是汗水all that kicking and running around, my hair and my face are wet with sweat. 朋友们,汗水是你的身体产生的最好的东西Sweat, my friends, is one of the best things your body will ever do! 当我们发热时我们的皮肤就会产生汗水,随着汗水干了,我们就会觉得凉爽Our skin makes sweat when we get hot, because as the sweat dries, it cools us down. 但是问题是:并不是所有动物的汗水都像我们一样But the thing is: not all animals can sweat like we do. 例如,狗,汗水只能来自他们身体没有被毛发覆盖的那一部分Dogs, for example, can only sweat through the parts of their bodies that aren’t covered 像他们走路时的爪子in fur, like the pads of their paws. 所以为了保持凉爽,他们通常舔他们的鼻子,当狗经历了大量短促的呼吸后So to keep cool, they lick their noses, and they pant — that’s when dogs take a lot 他们会伸出舌头来喘气of short, quick breaths, with their tongues sticking out. 随着他们舌头和鼻子上的水分干了后,就会变得凉爽——很像As the moisture on their tongues and noses dries, it cools them down — a lot like when 当你汗水干了的时候your sweat dries. 但是你知道谁会在保持凉爽上有更大的问题吗But you know who has an even BIGGER problem keeping cool? 考拉Koalas. 考拉栖息于澳大利亚,这里特别是在夏天会变得非常炎热和干燥Koalas live in Australia, where it can get really hot and dry, especially in the summer. 但是考拉不能排汗But koalas can’t sweat! 而且当它觉得很热的时候,他们不喜欢舔他们自己,因为这样做会AND when it gets really hot they don’t like to lick themselves, because doing that can 消耗他们身体内许多水分use up a lot of water in their bodies. 当你生活在一个炎热,干燥的地方,是很难得到水的And when you live in a hot, dry place, water can be really hard to come by. 那就是为什么考拉通常不喝很多水的原因。相反,他们通常And that’s why koalas don’t normally drink very much — instead, they usually get the 从他们吃的叶子上获取所需的水分water they need from the leaves they eat. 但是,如果考拉不能排汗,而且他们也不喜欢舔自己或者像狗一样的喘气But, if koalas can’t sweat, and they don’t like to lick themselves, or pant like a dog, 那么一只感到炎热的考拉会怎么做呢then what’s a hot koala to do? 就在最近,科学家们发现考拉是如何保持凉爽的Well, just recently, scientists have figured out how koalas keep cool. 他们紧抱大树They hug trees! 你一定听过吧You heard me right! 在很长一段时间内,科学家们都观察到考拉花很多时间For a long time, scientists have noticed that koalas spend a lot of their time with their 环抱着树干或者大树的分枝arms wrapped around the trunk or branch of a tree. 似乎这并不太让人惊讶,因为考拉几乎所有时间都在That might not seem so surprising, because koalas spend almost all of their time in the 树上trees. 但是这儿有很多其他的动物,像一些猴子也住在树上。但是But there are plenty of other animals, like some monkeys, that live in trees, too. But 他们并没有感觉需要一直抱着树木they don’t feel the need to hug trees all the time. 科学家们的发现表明,即使天气炎热,树木通常What scientists discovered is that, even when the weather’s hot, the trees are usually 比周围的空气更加凉快a lot cooler than the air around them. 所以,尽可能的用身体靠着大树,考拉自己会感到凉爽So, by spreading as much of their bodies against the tree as possible, koalas can cool themselves 而不会通过舔他们自己或者喘气丢失水分down — without losing water by licking themselves, or panting. 聪明的考拉!非常感谢参与这一期的儿童科学秀;随后这周可以查阅更多Clever koalas! Thanks for joining me at SciShow Kids; check back later in the week for more 关于动物和所有与科学相关的视频videos about animals and all things science!
  • 2021-08-28什么是流星雨?吱吱和我最近建造了一个瞭望台 我们也陶醉于用它来看Squeaks and I built this awesome observatory recently, and we love using it to look at 夜空the night sky! 如果你曾在晴夜仰望过夜空 你也许会注意到这里If you’ve ever looked up on a dark, clear night, you probably noticed that there are 繁华炫目a lot of things to see. 你能看见月亮 星星 甚至一些行星You can see the Moon, the stars, and even some planets! 如果你十分幸运 你也许会看到一颗流星:划过天际后的And if you’re really lucky, you might get to see a meteor: a streak of light that bursts 一条光迹across the sky. 因为流星产生的光看起来就像恒星所产生的亮光Since the light that meteors make looks kind of like the bright light that stars make, 许多人管流星叫“陨星”a lot of people call meteors “shooting stars.” 但流星根本不是恒星But meteors aren’t stars at all! 在太空中 恒星是由气体组成出口的大球体 离地球很远Stars are big balls of gas way out in space, far, far away from the Earth. 但流星的产生却是缘于小块岩石和金属被引力拉到了地球附近But meteors are caused by pieces of rock and metal that are pulled close to the Earth. 这一切都始于小块岩石和金属It all starts when a small piece of rock or metal breaks away 在遥远的太空中被分离出来from something bigger in space. 许多时候 这些小东西也不比一粒米大很多Most of the time, these pieces are small — not much bigger than a grain of rice. 有一些只有灰尘般大小And some are only about the size of a piece of dust! 当这些小东西向地球跌落时 他们的速度非常快 以至于加热了周围的空气When the pieces fall toward Earth, they’re going so fast that they heat up the air all 然后燃烧起来 使得空气绚丽夺目around them and burn up, making the air glow. 我们在空中看到的亮光——是一块小石头或金属在燃烧That’s the light we see in the sky — it’s a little piece of rock or metal burning up! 我们把下落的东西叫做流星体 它所产生的光是流星We call the falling piece a meteoroid, and the light it makes is the meteor. 当流星体彻底的燃烧 流星便消亡了 光亮也暗淡了When the meteoroid is completely burned, the meteor is gone, and the light disappears. 如果下落体很小 光亮或许会稍纵即逝If the piece is very small, the light might only last for less than a second. 如果下落体很大 光迹也许会划过整片天空If the piece is larger, though, the streak might race the whole way across the sky! 如果下落体足够大 它可以一直穿过大气层And if the piece is large enough, it can make it all the way through the layer of gases… 撞在地球的表面and hit the surface of the Earth. 如果发生了 它会得到一个新名字——一颗陨石If it does, then it gets a new name … a meteorite. [吱吱声][Squeaks squeaks] 我知道I know! 有很多单词听起来都非常相像That’s a lot of words that sound almost the same. 但他们完全不同 流星是一条光迹 流星体是But they’re all different: the meteor is the streak of light, the meteoroid is what 降落时的小岩石或金属we call the bit of rock or metal as it falls, and the meteorite is what we call it when 当它落在地面上时就称为陨石it hits the ground. 每年都有成千上万的陨石落在地球上 但他们中的绝大多数都是很小的Thousands of meteorites fall to the ground every year, but most of them are really small, 所以我们都没注意到他们so we don’t notice them! 更多的流星体甚至在落到地球上之前就燃烧完了And there are even more meteoroids that burn up before they can get to the ground. 在每年的某些时候 这会有比平常更多的流星During certain times of the year, there are a lot more meteors than usual. 一个小时内就有六十多颗There can be 60 of them in an hour! 这被称为流星雨 因为这有如此多的流星划过天际That’s called a meteor shower, because there are so many meteors falling through the sky 这很像我们在其中洗澡that it’s almost like we’re taking a shower in them! [吱吱笑声][Squeaks laughs] 我知道 这很有趣I know, that is kind of funny! 你能想像在跌落的岩石和灰尘中洗澡吗Can you imagine taking a shower in falling rocks and dust? 我想还是坚持用水来洗澡吧I think I’d rather stick to water instead 流星雨之所以产生 是因为在太空中叫彗星的东西Meteor showers happen because of something else in outer space, called a comet. 彗星通常离地球很远 始终处于Comets are usually very far away from the Earth, all the way out at the edge of the 太阳系的边缘solar system. 但有时 它会在地球绕着太阳转的轨道的附近But sometimes one passes close by, right near the path where Earth moves around the sun! 当它经过时 彗星上的一些灰尘脱落了 可以在这As it passes by, some dust from the comet breaks off, and the dust can stay in that 停留挺长一段时间spot for a really long time. 每年 当地球接近尘埃在太阳周围移动的地方Every year, when the Earth gets close to the spot where the dust is as it moves around 许多的尘埃向地球跌落 每颗小小的跌落物都会成为一颗流星the sun, lots of the dust falls toward Earth, and each little piece of it creates a meteor. 那就是我们所看到的流星雨That’s when we get a meteor shower! 全年都有几种不同的流星雨There are a few different meteor showers all throughout the year. 场面壮观的流星雨在一月 四月 五月 七月 八月 十月 十一月和十二月There are big ones in January, April, May, July, August, October, November, and December, 所以会有很多的机会去看他们so there are lots of chances to see them! 事实上 在今年吱吱和我将要去看最壮观的流星雨In fact, Squeaks and I are about to get to see one of the biggest meteor showers of the 它被称为英仙座流星群year, called the Perseids. 去看它的最佳的夜晚是在八月十二日左右The best nights to see it are right around August 12. 当你下次能去看流星雨时 你可以叫一名成年人You can ask a grownup to help you find out when you’ll next be able to see a meteor 去帮你查明shower. 然后你需要去找到一个漆黑的地方 抬头 接着欣赏流星雨Then, all you need to do is to find a dark spot, look up … and enjoy the light show! 你曾看见过流星吗Have you ever seen a meteor? 你认为流星雨如何呢How about a meteor shower? 请一名成年人帮你在下方发表评论吧 或者向我们 kids@scishow.com网站寄一份邮件吧Ask a grownup to help you leave a comment below, or send us an email at kids@scishow.com.
  • 2021-08-28NASA的捕获小行星计划欢迎收看SciShow Space News 我是这期节目的主持人Caitlin HofmeisterWelcome to SciShow Space News. I’m Caitlin Hofmeister, your host on our first voyage 觉得这个消息怎样 建一个机器人 把它送进太空together. So tell me how this sounds to you. We build a robot, huck it into space, use 用它捕捉一个千吨级的小行星 再把小行星带入近月轨道it to grab a thousand ton asteroid and park it in orbit around the Moon so astronauts 然后宇航员就可以登陆这个小行星 是不是听起来很棒啊can walk around on it, because I think that sounds awesome. And that’s exactly what 然而这就是NASA正在计划做的事情NASA’s planning to do. 自1998年以来 NASA近地天体观察计划就已经开始搜寻Since 1998, NASA’s Near Earth Object Observation Program has been searching local space for 可能会对我们造成威胁的彗星和小行星 到目前为止已找出超过10,000颗符合条件的小行星comets and asteroids that might kill us. So far it’s identified over 10,000 nearby asteroids, 现在NASA的科学家正在加快收集太空岩石数据的进程and now NASA scientists are ramping up their plan to use that data to take rock collection 几天前 NASA邀请各地技术公司帮助to a whole new level. A few days ago, NASA invited tech companies everywhere to help 构建探索新小行星计划所需要的数据build the technology they’ll need for their new asteroid retrieval mission. 小行星有可能是最棒的原材料来源 Asteroids have the potential to be a mindboggling source of raw materials. A space rock just 一颗直径500米的太空岩石含有的贵金属比我们所认知的储备量还要多500 meters across could contain more precious metals than humanities entire known reserve. 处于火星和木星间的16号小行星Psyche被认为有着1.7兆吨的One large asteroid between Mars and Jupiter named 16 Psyche is thought to hold 17 million 镍和铁 这足以满足地球数百万年对镍铁的需求billion tons of nickel and iron, enough to satisfy demand on Earth for millions of years. 还有 小行星上的水可以被用来做火箭去火星所需的燃料Plus, asteroids contain water, which could be used as a source of fuel for rockets enroute 所以收集小行星可能是殖民火星至关重要的一步 to Mars. So harvesting asteroids could probably be a crucial component of any serious 然而问题是这些东西都在太空attempt at colonizing Mars. The problem is that all that stuff is out there in space. 与此同时 小行星和地球都有着很长的一段历史 真是戏剧性Meanwhile, asteroids and Earth have a long history together and it’s full of drama. 那么 第一步就是从这些符合要求的小行星中带一个回来研究So, the first step in harnessing all the goodness from these rocks is to bring one home for 在2017年或2018年 NASA计划向第一颗小行星发射一个us to study. In 2017 or 18, NASA plans to launch the first asteroid redirect vehicle 像是带着大麻袋的50千瓦太阳能装置which basically looks like a 50-kilowatt solar-power array attached to a really giant sack. Using 利用太阳能飞行至NASA指定的地点 这大约耗时2年solar power, it’ll fly out to whichever asteroid NASA picks, taking about two years to get 当它飞到太空岩石附近时就用袋子把小行星包裹起来 然后拉着小行星there, and when it arrives at the rock it’ll just bag it. Then it’ll pull the asteroid 脱离它原来的轨道 利用月球引力把它拉向近月轨道out of its orbit so that it spirals in towards us just in time to get pulled into the lunar 整个过程将要2-5年orbit by the Moon’s gravity, a whole process that’ll take another 2-5 years. 然后 这个装置会带小行星进入所谓的逆行轨道After that, the vehicle will park the asteroid in what scientists call a distant retrograde 这个轨道大约在离月70,000公里左右 orbit, some 70,000 kilometers above the surface of the Moon. And then it’s just a 25 day 宇航员到达逆行轨道大约需要25天trip for a crew of two to fly out there and see what’s up. NASA predicts that astronauts NASA预测宇航员将在2025年登陆这颗小行星并采集岩石样品will be visiting our adopted asteroid by 2025 to inspect it, collect samples and eventually 直到最后这颗小行星的岩石被采集完 这将是我们有史以来对小行星的结构组成dismantle it. It’ll be our closest look ever at the structure and composition of an 最深入的一次研究asteroid. 现在你明白了吧 太空工厂和火星殖民可能还有很长一段路要走So there you have it. Space factories and Martian colonies might be a long way off, 为了让这个计划马上实现 我们需要大力发展科技but we’re developing the technology we’ll need to make them happen right now. 感谢收看我们的SciShow Space News 特别是支持我们的Subbable用户Thanks for joining me for SciShow Space News, especially to our Subbable subscribers who 如果你对我们的节目感兴趣make this channel possible. If you’d like a little bit of SciShow for yourself, like 想要得到我们节目的特制领带和巧克力棒的话 欢迎登陆subbable.com/scishowa SciShow tie or chocolate bar, go to subbable.com/scishow to learn more. And if you have questions or 如果你对这期视频有什么问题或想法 你可以通过脸书 推特或者像往常一样ideas for an episode you’d like to see, you can find us on Facebook and Twitter and, 在下面的评论区留言如果你想和我们一起变得越来越博识as always, in the comments below. And if you want to keep getting smarter with us, go to 记得订阅我们的youtube.com/scishowspaceyoutube.com/scishowspace and subscribe.
  • 2021-08-28科学解释说谎嘿 大家好 让我们玩个两真一假的测谎游戏吧Hey y’all, time for two truths and a lie. 我会告诉你们关于我的三件事I’m gonna tell you three things about myself, 你们要找出哪件是假的and you’re gonna have to pick out the one that is not true. 准备好了吗?好的 第一个 我家有一台机器Ready? Okay. Number one, I have a machine at home 可以把淡水变成碳酸饮料that transforms plain water into carbonated water. 二 我打牌技术非常糟糕Two, I’m really bad at the card game Set, or three, 三 迈克尔.杰克逊是我姑妈Michael Jackson is my aunt. 答案是否显而易见?Is it that obvious? [摄影师:是……] 唉 我对游戏真是太不在行了[camera man: Yeeeeah.] God, I’m so bad at game. [导入音乐][intro music] 撒谎!Lying! 我们经常撒谎 而且我们比自己想象的更擅长说谎We do it a lot, and we’re a lot better at it than you’d like to think. 比如 我不傻 相比于迈克尔.杰克逊是我姑妈 我完全可以说一个更好的谎Like, I’m not stupid, I could totally have made up a better lie than Michael Jackson is my aunt. 说白了 我看起来很不擅长说谎这件事 本身就是个谎言But check it out, the fact that I appeared to be terrible at lying was in fact…A lie. 我们人类与陌生人进行一次10分钟交谈 平均要说三次谎In a ten minute conversation with a stranger, we humans will tell an average of three lies. 研究说谎的调查者说 研究对象甚至往往意识不到自己在撒谎Researchers who study lying say that the subjects of these lying studies rarely even realize 这是为什么?撒谎究竟是为了什么?that they’re doing it. But why? What purpose does lying actually serve? 我们要理性地看待人类的撒谎行为 值得一提的是We’ll to put human deception into perspective, it’s worth 人类并不是自然界唯一会撒谎的生物pointing out, humans aren’t the only fibbers in nature. 有个关于非人类撒谎的很有趣的例子我特别喜欢 Koko 那只有名的大猩猩My favorite anecdotal example of non-human lying – Koko the gorilla 被教会了手语 那是在二十世纪七十年代的时候who was taught sign language back in the 1970’s 有一次 她把房间墙上的水槽扯了下来 却把责任推到宠物猫身上once actually blamed her pet kitten for ripping a sink out of the wall in her room. 真坏…大家都好坏啊 所以说撒谎在自然界真不算新鲜事Bad…bad All Ball. So yeah, lying is nothing new in nature, 但为什么人类特别爱撒谎?but why do humans specifically do so much of it? 正如我在之前的一次SciShow中提过的 人类是最早的也是最有代表性的社会性动物Well as I’ve mentioned here before on a SciShow, humans are first and foremost social animals. 人类拥有超极容量的大脑 这主要是因为我们需要它去处理时时刻刻的社会交流信息Got really super huge brains, and that’s mainly because we need them for all the interacting we’re always doing. 对于人类而言 成功的社会交流是生活中很多事情成功的关键For humans, successful social interaction is key to success in much of our lives. 所以很明显撒谎是很不错的方法 不仅可以维护精密的社会结构平稳运转So it’s clear that lying is a great way of keeping elaborate social structures running smoothly 同时还可以寻求自身利益最大化while looking out for number one. 打个比方 如果你可以让同伴高兴 你将得到非常多的好处 比如食物For instance, if you can keep your social group happy you’re going to reap all kinds of benefits like food, 更高的社会地位 更多更好的配偶 你知道你没法higher social standing, more and better sexual partners, and you know you don’t 交到朋友或是影响周围的人们make friends and influence people going around saying things like “Actually, that 仅仅通过说“确实 那件腰布裙使你的屁股看上去很大” 或是loin cloth does make your butt look big,” or “嘿 你出去猎乳齿象那会我和你哥哥做爱了“Hey, uh, I have been having sex with your brother while you’re out hunting 所以那边的小Glurgmastodon, so the little Glurg over there’s… 可能是你的侄子” 所以说谎probably your cave nephew.”So the ability to lie, 和识破谎言的能力 对于早期的人类变得十分重要 因为and to detect a lie, became pretty important to early humans because lying 说谎对于大脑来说确实不是很容易 它实际上会导致is actually not very easy for a brain to do, and it actually caused a bit 大脑的进化竞赛of an evolutionary arms race. 于是人们开始变得越来越擅长撒谎 而且更擅长撒谎的人会得到更好的东西So people started to get better and better at lying, and better liars got better stuff, 同时很有希望在团体里保持好的地位while hopefully remaining in good standing with their communities. 同样的 那些更擅长识别谎言的人By the same token, those who were better at detecting lies 被配偶欺骗或者在骆驼交易中翻船的几率会小很多were cheated on by their mates and screwed over in camel trades a lot less often. 所以是的 我们现在已经进化成撒谎高手 并且很擅长识别低级谎言So yes, now we’ve evolved to be good liars and also good at spotting bad liars. 但随着社会变得越来越复杂 人们会说“好了 好了 别再撒谎了!”But as societies became more sophisticated, folks were like “Okay okay, enough with the lying!”, 因为生活在结构紧密的团体或者有组织的社会中 有很多好处because there are lots of advantages to living in tight-knit communities and structured societies, 但是你无法真的拥有它们but y’can’t really have them, 当你不确定你正在抚养的小孩是否是自己的when you don’t know for sure if the kids you’re raising are yours, 或者你刚买的骆驼是否出过事故或其它……诸如此类的事and if the camel you just bought has ever been in an accident or…Whatever. 而一个对厚颜无耻的面对面谎言完全不加以抑制的社会So a society in which bold face lying goes completely unchecked leads 会……完全失去秩序!to… total anarchy! 所以有组织的社会开始使用锤子进行打击So organized societies started putting the hammer down. 宗教系统开始引导人们 上帝会奖励和关爱说真话的人Religious systems began to drive home the point that God rewards and cares for the truthful 也会惩罚说谎者and punishes liars. 所以如果你绑着一袋锤子被扔进池塘还能活下来So if you could survive being thrown into the pond tied up with a 那么上帝是站在你那边的 你说的那些是真话sack of hammers, God was on your side and you were telling the truth. 如果没能活下来 那么很明显 你在撒谎If not you were obviously lying. Oh!中世纪欧洲的审判系统 我是多么爱你Oh, medieval European judicial system, how I love you. 即使是现代社会 也有法律明令禁止说谎Even in our modern times there are laws that prohibit lying and 罔顾我们言论自由的权利override even our rights to free speech. 比如 你会因为在法庭上撒谎或者谎称For instance, you go to a jail for lying in a court of law, or for lying about having received a 自己因为在军队的奉献而收到了荣誉勋章而蹲监狱Medal of Honor for service in the armed forces. 别那样做 因为你又没那么……邪恶Don’t do that. Also ’cause you’re not… evil. 为什么有人会撒谎呢 撒谎 是不对的Why would someone do that? So lying. It’s not okay. 但是同时我们又擅长撒谎 而且我们的大脑想要撒谎But we’re also good at it, and our brains want to do it. 我们非常小的时候就开始撒谎 一些研究者声称我们早在六个月大时就会说谎We start lying really early, some researchers say as early as six months old. 我指的是 你也见过婴儿装哭 对吧?I mean you’ve seen a baby fake cry, right? 那很容易看出来 比如他们正在哭[模仿婴儿假哭音] 然后他们会看一下是否有人It’s very obvious, like they’re crying [fake crying noises] then they like, check to see if anybody’s 过来表示一下关心 再然后他们会像这样“懊 我要接着哭了!”coming over to sympathize, and then they’re like “Oh, I’m going to keep crying then!” 科学家们认为这是婴儿Scientists think that this is the time when babies 正式开始学习怎么成为一个更好的撒谎者的时候are actually learning how to be better liars. 到了上大学 每五次和妈妈的交流中 他们大约会撒一次谎By the time the kid’s in college they’re lying to their mom about once in every five interactions, 而实际上这对我来说是低水平的And actually that seems low to me. 我想说依我的大学经历 五次交流里我会说五次谎I would say five out of five for my college experience. 这就是现在的孩子Kids these days. 确实 孩子每天都撒谎Actually, kids every day. 到我们成年 我们已经相当擅长撒谎By the time we’re adults, we’ve gotten so very good at lying that we’re 事实上我们还可以非常有效地欺骗自己actually able to do it to ourselves very effectively. 所谓欺骗自己 就是在我们的脑中The trick to lying to yourself is in the holding of two pieces of 有两条相冲突的信息同时存在 我们只关注了其中一条conflicting information in your head at the same time and paying attention to one, 而忽略了另一条while ignoring the other. 善于撒谎的人的大脑能将一连串相冲突的信息马上全部处理完People who are good liars can hold a bunch of conflicting information in their heads all at once, 并且一切信息尽在掌控and keep track of it all. 拿那些病态撒谎者举例 即那些Take pathological liars – people who habitually and compulsively 撒谎成性 欺骗成瘾 爱操纵别人的人lie, cheat, and manipulate other people. 病态撒谎者非常擅长自我欺骗The thing about pathological liars is that they’re super good at self deception. 当他们说谎时 他们全心全意地相信自己所说的话At the moment they’re telling it, they whole-heartedly believe their own lie. 有趣的是Interestingly enough there is 的确存在不同 在正常人的大脑an actual difference between the brains of a normal person 和病态撒谎者的大脑之间and the brain of a pathological liar. 不同之处在大脑最前部一个叫做前额皮质层的地方That difference is in the very front of the brain in a place called the prefrontal cortex. 大多数神经科学的研究集中在Most neuro-science studies focus on the 大脑的灰质 那些物质实际上负责处理信息的on the gray matter of the brain, that’s the material that actually processes information. 然而 我们的大脑几乎有一半是由所谓的白质构成的However, nearly half our brains is made up of what’s called white matter, which is 它由结缔组织组成composed of connective tissues that 结缔组织将电子信号从一组神经元传递到另一组carry electrical signals from one group of neurons to another. So grey matter is 所以灰质负责所有的信息处理 白质负责连接where all the processing happens, and white matter connects the different 大脑的不同部分parts of the brain. 在南加州大学的一项研究中 研究人员发现In a study at the University of Southern California, researchers found that 病态说谎者pathological liars 前额皮质层的白质比一般人多约25%have about 25 percent more white matter in their prefrontal cortex than the rest of us, 这表明病态说谎者可以非常迅速地在大脑中做出一连串的联系suggesting that pathological liars can make a bunch of connections in their brain really fast. 这让他们有条理地记住所有需要的信息And that lets them keep all the information in order that they need 以此维持谎言to sustain the lie, 同时解读他们正在欺骗的人 对那些人进行施压also to read the person that they’re lying to, to suppress their emotions, 最重要的是 使对方有可能相信他们所说的and probably believe what they’re saying on top of it all. 所以 为什么病态说谎者还没有接管这个世界So, why haven’t pathological liars taken over the world? 我的意思是他们似乎是人类进化的下一步I mean they seem to be the next step in human evolution. 其实不然 病态说谎者是有比较多的白质While pathological liars have a surplus of white matter, 但同时他们的灰质比其他人少14%左右 而灰质they also have around 14 percent less gray matter than other people, and gray matter 是所有批判性思维发生的地方is where all the critical thinking happens. 所以白质多的人只会说 “我要告诉吉姆我以前是个战斗机飞行员!” 而灰质多的人则会分析So the white matter is all alike, “I’m gonna tell Jim I used to be a fighter pilot!” and the grey matter’s all “我可以告诉吉姆我以前是个战斗机飞行员 但我也许不应该这样做 因为“I could tell Jim I used to be a fighter pilot, but I probably shouldn’t because 那会危及我和苔米的关系”that would jeopardize my relationship with Tammy.” 所以说极端说谎者很难维持人际关系并So extreme liars have a really hard time maintaining relationships and 保住工作 因为不久之后每个人都会意识到holding down jobs because after a while everybody realizes 他们满脑子废话 结果是被抛弃或被解雇that they’re full of crap, and they get dumped or fired. 这对说谎者来说是适得其反Which is not ideal for the person. 但对其他人都是好事It’s great for everyone else. 但如果真有超级骗子 我们要怎么知道自己是否正在被欺骗?But if there are these super liars out there, how do we know if we’re being lied to? 我的意思是 测谎仪也许可以捕捉到信号 比如骗子声音的变化I mean, lie detectors might be able to pick up signals like change in the liar’s voice, 或心率的增加 或出汗 所有那些or increased heart rate, or sweating, all stuff that we 在我们真的在撒谎时的身体变化do when we’re fibbing outright. 但是一个真的擅长撒谎的人也许不会显示任何这种症状But a really good liar might not display any of those symptoms. 然而 无论你是一个多么好的说谎者Well, no matter how good of a liar you 你正在说谎这件事are, the fact that you are lying 常常会露馅 通过你的肢体语言和你的词汇选择will often leak out, both through your body language and through your word choices. 让我们看一个简单的句子Let’s look at a sample sentence. “相信我 我不是那个放屁的和导致人们撤出那家电影院的人!”“Believe me, I was not the one who farted and evacuated that movie theater!” 你相信我吗?So do you believe me? 可能不相信 因为在那个句子里我做了三件事情 使你Probably not, because I did three things in that sentence that made you 完全确信实际上是我让他们撤出totally certain that I was in fact the person who made them evacuate 电影院的the movie theater. 即:一 我说“相信我” 而骗子总是会那样说To wit: one, I said “believe me”. Liars will always say that, 或者“老实说” 又或者理查德.尼克松最喜欢的“坦白讲”or “to be totally honest”, or Richard Nixon’s favorite “in all candour”. 二 我突然停止使用缩略语Two, I all of a sudden stopped using contractions. 撒谎者经常使用更正式的语言来否认他们确实做过的事情Liars often use more formal language to deny something that they’ve actually done. 三 我说“那家电影院”而不是“电影院”And three, I said “that movie theater” instead of “the movie theater” – I was 我正在试图与整个局势保持距离trying to distance myself from the whole situation. 我们以为说谎者是坐立不安的 但实际上我们倾向于在说谎时保持上半身僵硬We think of liars as being fidgety, but we actually tend to freeze our upper bodies when we lie. 我们会做更多的 而不是更少的目光接触We make more, not less eye contact. 为了撒个小谎这也许有点矫枉过正了Maybe a little too much to overcompensate for telling a fib. 说谎者还会做下面这些事 比如在说“是”的时候摇头Liars will also do things like shake their heads while saying yes 比如讲完一个故事会笑 即使那是个恐怖故事and smile when they’re done telling a story even if it’s a terrible one. 所有这些 通过观察我们的用词以及肢体语言所泄露的信息All of this stuff, the reading of what we leak through our words and bodies is 实际上是测谎的未来趋势actually the future of lie detection – 训练执法人员去解读潜在罪犯(所泄露出来的信息)training law enforcement officers to read potential criminals to catch them 从而在罪犯说谎时将其逮捕in the act of lying. 当然人们也常常发明出各种各样的新的小工具Of course they’re always coming up with new kinds of gadgets all the time too. 眼球跟踪器 核磁共振成像脑部扫描仪将会代替老式测谎仪Eye trackers, MRI brain scanners that are going to replace the old lie-detector tests. 也许我可以试试对着脑部扫描仪说我的两真一假 看看它会怎么反应Maybe I’ll tell my two truths and a lie on a brain scanner, see how it does. [摄影师:非常确定我们都知道会发生什么] 好吧 你是对的[camera man: Pretty sure we all know how that’s going to turn out.] Yeah, you’re right. 我是一个糟糕的说谎者 也许不是?I’m a terrible liar. Or am I? [疯笑][maniacal laughter] 感谢观看这期节目Thank you for watching this infusion. 我们讲述的所有的事实都不是谎言 我们保证All of the facts contained within are not lies, we promise. 但是如果你想较真 描述部分有写明引文出处But if you wanna check there are citations in the description, 是的因为我们在这里是科学家of course because we’re scientists here. 如果你对未来的节目有想法 你可以在评论区留言If you have ideas for future episodes of infusions you can leave those in the comments 也可以通过Facebook或Twitter联系我们or connect with us on Facebook or Twitter. 有问题也欢迎来问 我们同样会非常开心去解答 下次见Also questions, we’ll be happy to answer those as well. See you next time. [结束曲][ending music]
  • 2021-08-28人们真的会因为年龄太大而死去吗?在某些观点中 你很有可能已经听说过At some point, you ’ ve probably heard 在通常情况下 一个人一般被认为是“因年老而死”of someone who supposedly “ died of old age. ” Usually, 这就是说他们的死亡与变老有关that just means they died of complications related to getting older, 或者由于某些情况or from something 一个更年轻的人有可能从疾病幸存 比如肺炎a younger person might have survived, likepneumonia. Because, 因为即使年龄能够加速一些人的死亡速度even though age can contribute to someone ’ s death, 事实几乎上完全不是这样it almost definitely won ’ t 年龄不是直接原因be the direct cause. 我们身体内的细胞的确有固定的使用寿命The cells in our bodies do have a set lifespan — 或者一种现象表明它们不再分裂or a point at which they quit dividing 但是你永远不会看见这被写在一张死亡证明上— but you’ll never find that written ona death certificate. 这叫做细胞衰老It ’ s called cellular senescence, 科学家们认为这极有可能是因为一些小构造and scientists think it ’ s mostly because of little structures 存在于你的染色体的末尾的染色体终端on the end of your chromosomes called telomeres. 染色体终端是重复的脱氧核苷酸的扩张部分 也是组成DNA的混合物Telomeres are stretches of repeating nucleotides, the compounds that make up DNA. 它们像帽子一样覆盖基因原料的顶端去保护它们And they act as caps to protect the genetic material 在你的染色体移动 复制的时候in your chromosomes during cellular reproduction. 每次细胞分裂时Each time a cell divides, 这些染色体终端就会变短一点 多亏了那种特殊结构those telomeres get a little shorter, thanks to the mechanics 当染色体复制的时候of how chromosomes are copied. 当它们变得足够短时 细胞衰老就开始了And when they get short enough, senescence sets in, 这些衰老的细胞再也不能复制了and the cell can ’ t duplicate itself anymore. 但是其它因素也可以加速细胞老化But other factors also contribute to cellaging. 一种就是氧化反应One is oxidative stress, 或者由于剧烈的化学反应对你的DNA造成的伤害or damage done to your DNA by highly reactive molecules that 包括氧化反应contain oxygen. 另一种就是糖化Another is glycation, 就是当糖分子附着在你细胞的主要部分上which is when sugar molecules bind to key parts of your cells 然后糖分子就会阻止这些细胞的功能 不幸的是and prevent them from functioning. Unfortunately, 所有的这些随着时间的流逝都是无可避免的all of these things are prettymuch inevitable over time. 你可以采取一些措施去抵抗他们 比如You can take some actions to combat them — like, 你可能听说过抗氧化剂you might ’ ve heard how antioxidants in certain 食物可以抵抗氧化的影响foods can fight the effects of oxidation — 但是你不能完全停止它们but you can ’ t stop them completely. 在你的细胞完全不能复制之前Scientists aren ’ t sure how old you ’ d have to be 科学家们不知道你究竟能活多少岁before your cells just couldn ’ t duplicate anymore, 而这是but that ’ s 因为年龄性的疾病和损伤往往会because age-related diseases and injuries will catch up with someone 远早于细胞衰老直接导致的死亡long before they can die directly of cellularsenescence. 当一个人变得越来越老 所有这些来源引起的损伤堆积在一起As someone gets older and damage from all these sources pile up, 他们的细胞更有their cells are more 可能在一些问题发生时 在正常工作和自我修复方面出现问题likely to have problems working correctly and fixing themselves when something goes wrong. 就是说他们的免疫系统变得更不堪一击了That means their immune system gets weaker, 他们变得更容易被这些情况影响然后患上and they become more susceptible to all kinds 所有种类的损伤和疾病 例如心脏病和高血压of injuries and diseases, like heart and blood pressure problems, 还有阿兹海默症and Alzheimer ’ s. 当这些疾病出现时When these diseases appear, 它们能够影响人们自由行动和自理的能力they can affect someone ’ s ability to get around and take 同样它们也可以导致一些器官类的疾病care of themselves, and can also cause problems in their organ systems. 即使年龄可能是一个促进因素And those will be the direct causes of death, 但是那些才是直接导致死亡的原因even though age may be a contributing factor. 感谢Patreon的赞助人Tommy Boyer的技术支持Thanks to Patreon patron Tommy Boyer for asking, 感谢所有的投票支持者and thanks to all of our patrons who voted 帮助我们票选出这个问题进行解答on our poll to help us choose this question to be answered. 如果你想要提出你的问题 帮助西客秀继续存在下去If you ’ d like to submit your questions and help SciShow keep existing, 访问以下网址 “patron.com/scishow”go to patron.com/scishow.
  • 2021-08-28火山的一切:它们如何形成、喷发还有更多嘿 Squeaks 你知道吗 昨晚你熟睡的时候Hey Squeaks, did you know that while you were asleep last night, a volcano off the coast 意大利的一座沿海的火山大喷发了耶of Italy was wide awake? 斯特隆博利岛火山已经持续喷发至少2000年了The Stromboli volcano has been awake for at least the last 2,000 years! 也就是说 它和别的火山相比 喷发时间更长That means it’s been erupting for longer than any other volcano. 斯特隆博利岛的火山喷发很频繁 基本上没停过Stromboli’s eruptions happen really often, practically non-stop! At night, its glowing 夜晚 火山口发出火光 让人觉着那就是个巨型灯塔light-shows have reminded some people of a giant lighthouse. [松鼠语][Squeaks squeaks] 真是个好问题一个像斯特隆博利岛的火山起初是That’s a really good question! How does a volcano like Stromboli form in the first 怎么形成的呢place? 在地球深处 我是说比我们的地下室还要深还要深的地方Deep inside the Earth — and I’m talking waaaaay deeper than our fort goes — it’s 那里相当热really hot. 热到能把组成地球的那部分岩石都融化了It’s so hot that the rock that makes up this layer of the earth is actually melted! 那部分融化的岩石叫岩浆It’s called magma. 有时候 岩浆可被储存在地壳下Now, sometimes magma can collect in a pocket just beneath Earth’s surface, and if the 但如果岩浆从地壳下喷溢出来 然后碰到空气 就形成了熔岩magma breaks through all the way to the surface and reaches the air, it’s called lava. 观众朋友们 现在你的手上就有个火山And now, my friends, you have a volcano on your hands. 当熔岩一开始从地下喷出来的时候 它是鲜红滚烫的Lava is bright red and very hot when it first erupts out of the ground. But soon the lava 但很快 等熔岩冷却下来 就变成了一层岩石cools down and creates a layer of rock. 随着时间推移 流出岩浆的地点周围就会形成多层岩石堆积而成的火山堆Over time, many layers build up around the spot where the lava came out, to form the 也就是大多数人认为的火山mountain that many of us think of as a volcano. 如果火山持续喷发 那火山堆就还会继续变高And if the volcano keeps erupting, it keeps growing. 随着每个火山的喷发 更多的岩浆从中部形成的管道流出With each eruption of a volcano, more magma flows up the tube that forms in the middle, 这就是火山通道 当从顶部流出时 就是火山口called the vent, and it comes out at the top, called the crater. 等岩浆冷却下来变成坚硬的岩石后 火山就又变高了Then, once more, the lava cools and hardens into solid rock, and the volcano has grown! 但其实每座火山的形状和喷发都是不一样的But not all volcanoes look, or act, the same. 火山的形状决定了岩浆是怎么从火山口喷出来的Lava can come out of craters in different ways. It depends on the type of volcano. For 对于很多火山来说 比如斯特隆博利岛火山 岩浆就像炙热的泉水一样喷涌而出some volcanoes, like Stromboli, lava shoots out like a fiery fountain. 当斯特隆博利岛火山这样喷发时 大块的熔岩和石块When Stromboli erupts like this, big blocks of lava and stone can be thrown hundreds of 可能被抛到数百米远meters away. 至于别的火山 岩浆只是从火山口慢慢溢出 就像是粘稠的糖浆But for other volcanoes, lava just oozes out of the crater, more like a lazy syrup. 随着时间推移 这种慢慢形成的熔岩也就形成了巨大的火山Over time, this slow-moving lava can create massive volcanoes, too. 夏威夷岛的莫纳罗亚火山就是这样的 并且它是世界上最高的火山One volcano like this, called Mauna Loa in Hawaii, is the tallest volcano in the world. 事实上 夏威夷群岛是由火山的水下喷发形成的And in fact, all of the islands of Hawaii are made of volcanoes that began underwater. 这过程已经持续数百万年了 随着时间推移 所有的熔岩层越堆积越高They’ve been growing for millions of years, and over time, all of the layers of lava that 直到浮出水面have oozed out have built up, until they reached above the surface of the ocean. 意大利的斯特隆博利火山也是这样的Our fiery old friend Stromboli, in Italy, formed this way, too. Its whole island is 整个岛基本上就是个大火山basically one big volcano! 你不必非要有个地下城堡来了解So, you don’t have to have an underground fort to know that there’s a lot of amazing 这里发生了什么有趣的东西stuff going on beneath the surface of the Earth. 一直以来都有一股不可思议的力量在塑造着我们生活的这个世界There are incredible forces at work all the time shaping the world that we live in. 感谢收看《SciShow Kids》嘿 Squeaks 在这个火山实验喷发前Thanks for watching SciShow Kids! Hey Squeaks! Let’s get going before one of our experiments 我们快点离开吧erupts!
  • 2021-08-28地球能有多冷?Thanks to Brilliant for supporting this episode of SciShow.感谢Brilliant对本期《科学秀》的支持 Go to Brilliant.org/SciShow to learn how登录Brilliant.org/SciShow学习如何 you can take your STEM skills to the next level.把你的理工科技能提升到一个新的水平 地球能有多冷? In July 1983, a weather station in Antarctica1983年7月 南极洲的一个气象站 recorded the lowest air temperature ever measured on Earth.测量出了地球史上的最低气温 It was about -89 degrees Celsius…大约是-89摄氏度 which is colder than the average temperature on Mars.比火星的平均温度还要低 But 25 years later, scientists analyzing satellite data但25年后 科学家分析卫星数据时发现 found small pockets high up on the East Antarctic Plateau在南极洲东部高原之上的小片地区 where temperatures routinely drop about five degrees lower,其温度会在定期降到-94℃左右 making them the coldest spots we know of on Earth.成为地球上已知最冷的地方 But these pockets aren’t just for record books:但这些地区不只创造低温记录 They’re also helping us understand how cold it’s possible to get on the surface of our planet还有助于我们了解地球表面能有多冷 and what conditions it takes to get that cold.以及什么条件下会如此寒冷 These record-breaking temperatures happen during long这些破纪录的温度都是在 polar nights within little hollows in the ice sheet,极地极夜时 more than three-and-a-half kilometers above sea level.海拔3.5公里以上的冰原小洞里量出的 On still nights when the sky is clear,在晴朗无风的夜晚 the air near the surface of the snow cools down当热量辐射到太空时 as heat radiates into space,雪面附近的空气会变冷 and it becomes denser than the slightly warmer air surrounding it.比周围温度略高的空气有更大的密度 As a result, it starts sliding downhill along the ice sheet于是 它开始沿着冰原向下滑动 and sinks into these hollows.沉到这些洞里 If the wind is light enough, the super-cold air gets trapped down there,如果风够小 超级冷空气就会困在那里 and it acts like a kind of ice pack,就像一个冰袋 which brings down the temperature of the surface even more.进一步降低了地表的温度 When that happens,当这种情况发生时 the air temperature drops down to those record low气温会降至历史最低水平 until weather stirs things up again.直到受到天气的干扰 But the lack of wind isn’t the only thing you need to get those temperatures.但少风并非是导致低温的唯一条件 It also has to be extremely dry,还必须非常干燥 because water vapor can keep heat from escaping.因为水蒸气可以防止热量流失 See, heat might feel like this abstract thing,热量一词听起来可能感觉很抽象 but it’s just waves of infrared radiation.但它只是红外辐射波 So when heat escapes our planet,所以当热量从地面散发出去时 infrared waves are radiating from the ground and into space.红外波从地面辐射到太空中 When temperatures drop, there’s less heat coming from the surface,当温度下降时 来自地表的热量就会减少 so the waves carrying that heat away lose energy and stretch out.所以携带热量的红外波会失去能量 波长会变长 And those longer waves are more easily absorbed by water vapor in the air.更长的电磁波更容易被空气中的水蒸气吸收 So if there’s any moisture in the air,所以如果空气中有水分 a lot of that radiation won’t escape into space;很多辐射不会进入太空 it will be absorbed by the water它会被水吸收 and sent back to the ground to warm things up.然后返还地面 增加地表温度 In fact, to get below about -90 degrees,事实上 要想温度低于-90度 you need less than a millimeter’s worth of water in the entire atmosphere从地表到太空的整个大气中 stretching from the ground all the way into space.降雨量要低于一毫米 In other words, if you wrung out all the water from that air,换句话说 如果你从空气中拧出所有的水 it wouldn’t even reach the one-millimeter line on a rain gauge.它甚至连雨量计上的一毫米都达不到 Those are some strict requirements.这些要求都十分严格 But for the researchers studying this,但对研究人员来说 the really surprising thing wasn’t just that真正令人惊讶的事情不仅是 the temperature got so low in these pockets:这些地方的温度变得很低 It was that, over time,而是随着时间的推移 it dropped to nearly the same low temperature over and over again.温度反复下降 但与之前的记录几乎一致 Like, across 14 years and hundreds of kilometers of the Plateau,比如 历经14年 在数百公里的高原 the lows at the coldest sites hovered right around -94 degrees,最冷地区的最低温度在-94度左右上下徘徊 just above the all-time low of -98.略高于历史最低点-98 So scientists wondered if the temperature was hitting some kind of threshold因此 科学家猜想温度是否达到了某种阈值 if it was reaching the coldest temperature possible on the surface of our planet.是否达到了地球表面可能达到的最低温度 And that seems to be what’s happening!这件事情似乎正在发生! See, even on still, dry nights,你看 在干燥平静的夜晚 the heat doesn’t radiate away forever.热量永远也不会散发出去 Instead, a lot of that infrared radiation gets trapped by carbon dioxide相反 大量的红外辐射会被二氧化碳捕获 because while CO2 always absorbs some heat,因为二氧化碳总是会吸收一些热量 it’s especially good at absorbing these longer wavelengths.尤其擅长吸收较长的电磁波 So at that point, the air itself is trapping heat所以在这一点上 空气本身就在吸收热量 and sending it back toward the surface.然后把它送回地面 The atmosphere essentially acts like a blanket,大气就像一张毯子 and heat can only escape from the surface really slowly.热量只能缓慢地从表面逸出 Eventually, around -98 degrees Celsius,最终 到-98摄氏度左右 the temperature is dropping less than half a degree a day温度开始以一天不到半度的温度下降 too slowly to really change温度降低得太慢 以至于 befor the weather shifts and winds stir things up.在天气变化和有风干扰之前 还无法降下来 In theory,理论上 if air could sit still for days or weeks on end,如果空气可以连续几天或几周保持静止 the temperature could drop lower,温度可能会下降得更低 but on a planet with so much weather,但在一个气候多样的星球上 -98 degrees is essentially as cold as it gets.-98度基本上是能达到的最冷温度 Which, hey, is fine by me.这对我来说 倒无所谓 It takes some creative thinking发现和揭开某些事物的神秘面纱 to find and demystify something like比如地球上最冷的地方 the coldest place on Earth.需要一些创造性思维 And if you’re interested in learning to think like a scientist如果你很有兴趣想学会像科学家一样思考 or better understand the science behind discoveries like this或更好地理解这类发现背后的科学原理 you might be interested in the courses offered by Brilliant.你可能会对Brilliant提供的课程感兴趣 Brilliant offers dozens of courses in science, engineering, and math.Brilliant提供数十门科学 工程和数学课程 They’re hands-on,这些都是需要亲身实践的课程 with interactive quizzes and guided problems, with explanations有互动式测验 指导问题 并进行解释 all designed by educators at leading universities,都是由顶尖大学的教育工作者设计的 like MIT, Caltech, and Duke.比如麻省理工学院 加州理工学院和杜克大学 And you can save 20% on an annual premium subscription如果你是Brilliant.org/SciShow网站首批注册的前200人之一 if you’re one of the first 200 people to sign up at Brilliant.org/SciShow.年费会员可以打八折哦
  • 2021-08-28如何搭建一个毛毯城堡[简介][Intro] 看这里Hey there! Squeeks和我刚刚在外面玩 我俩搭了一个毛毯城堡Squeeks and I are just hanging out, building a blanket fort. 没错 我们搭了个城堡…在我们的城堡里That’s right! We built a fort…inside our fort! 我敢打赌 你以前也搭过城堡 如果你发挥想象I bet you’ve built a fort before, too. If you use your imagination, you can come up 你可以用各种创意 搭建出自己的空间 用来阅读、吃零食with all kinds of creative ways to make a space of your own, for reading, snacking and 还有躲藏!— hiding! 你可以使用靠垫 毛毯 甚至是家具 但不管你是怎么搭的 所有的城堡You can use cushions, blankets, and even furniture. But no matter how you build them, all forts 都有个很重要的共通点: 它们需要搭在一起的力have one really important thing in common; they need forces to stay together. 你可能记得我们之前讨论过“力”––推和拉You might remember that we’ve talked about forces before—they’re the pushes and pulls 物体间互相作用that objects put on each other. 力无处不在 工程师经常研究力Forces are everywhere. And experts called engineers are always studying forces, so they 所以他们能设计建造摩天大楼和桥梁can design and build things like skyscrapers and bridges. 那么 当你建造自己的城堡时你就是一个工程师!So when you build your fort… you’re thinking like an engineer! 现在 如果你要搭建一座完美的城堡 你需要知道的一种力Now, if you’re gonna become a successful fort builder, one of the forces you’ll need 就是—-张力to get to know is called tension. 张力的意思是 把物体拉紧 所以这是一种拉力Tension is just another word for pulling something tight, so it’s a force that pulls rather 而不是推力than pushes. 如果你觉得张力耳熟 那是因为我们之前讲过它And if tension sounds familiar, it’s because we’ve talked about it before! 之前我们的节目收到来自观众的问题 大桥为什么这么结实When an awesome SciShow Kids viewer wrote in to us to ask why bridges were so strong, 我们讲解了原因 吊桥重要的力之一就是张力we learned that tension is one of the forces that help suspension bridges hold up the cars 它使得汽车和卡车能安全通过吊桥and trucks that drive across them 吊桥被钢索吊起。。。再用很重的锚拉紧这些钢索And that’s because the bridge is held up by cables…and the cables are pulled tight 这些锚被深深地沉入桥两端的地下by heavy anchors that are sunk deep into the ground on either side of the bridge. When 当钢索被牵拉时 就产生了张力 这样就能吊起大桥了the cables are pulled, it creates tension, which holds up the bridge! 那么 你应该怎么利用这种力建造一座城堡So! How can you build a fort using the same force that holds up giant structures like 就像金门大桥那样the Golden Gate Bridge? 首先 形成张力 你需要一些能拉紧的东西 比如说Well, to make tension, you’ll need something you can pull tight, like a sheet from the 亚麻织物衣橱里的床单linen closet. 然后 找来一对椅子 一些很重的书 把床单的边Next, you can grab a couple of chairs, a few nice heavy books and then put the ends of 搭在椅背上 接着把书压在床单的四个角上the sheet over the backs of the chairs. Then you can put the books on each corner of the 这样就拉紧了sheet, so it’s stretched tight. 书就像是锚 让床单的四个角相互分开The heavy books acts like anchors, pulling the corners of the sheet away from each other. 这样把床单拉开 形成了张力 就像吊桥那样This stretches the sheet tight, and causes tension, just like the suspension bridge. 现在 你有了一个漂亮的屋顶And now, you have a nifty roof for your fort! 但是这只是其中一种方法But that’s just one way that you can use tension to build a fort. 让我们试试另一种Let’s try another design. 用绳子怎么样?把绳子系在一个很重的 坚固的家具上 比如床柱How about tying a string to a big, heavy, sturdy piece of furniture, like a bedpost? 然后把绳子拉直 另一头也系在牢固的家具上Then you can pull the string tight, and tie the other end to something heavy, too. 系好以后 把床单盖在绳子上 用厚的书固定床单的每个角Once you’ve done that, you can drape the sheet over the string, anchor the edges of the sheet 这样你就有一个帐篷了!with your heavy books, and then you’ll have a tent! 这个帐篷才是一箭双雕因为我们在两个不同的地方This tent-fort is actually a tension two-fer! Because: We’ve used tension in two different 都利用到张力places. 绳子在两个家具之间拉紧The string is pulled tight between the two pieces of furniture, and the sheet is being 由上面的绳子和下面的书的重量 拉紧了床单pulled up by the string, and down by the weight of the books. 没有张力 柔软的床单就不能形成任何形状 你应该说Without tension, that floppy sheet wouldn’t have any shape. You could say: The force makes 是力造就了城堡the fort! 现在你只需要一个手电筒和一些零食无论你想蜷缩在城堡里看书 吃零食All you’ll need now is a flashlight and some snacks. So whether you’re in the mood to snuggle 还是只需要一个极佳隐匿点up with a book and a couple of cookies, or just make a super-secret hideout, all you 你只需要一个床单 一些用来悬挂的东西 一些锚 还有想象力need is a sheet, something to hang it on, some anchors, and your imagination. Tension 张力会做好其余的一切will do the rest. 你是怎么搭建自己的城堡的你有过自己的得意作品吗How do you like to build your forts? Have you made one that you’re really proud of? 给我们发来照片 或者询问我们任何问题Send us a picture! Or ask us about anything that’s on your mind! Just leave a comment 只要在下方评论 或者发送邮件下次见below, or email us at kids@thescishow.com, and we’ll see you next time!
  • 2021-08-28为什么有的人对辛辣的食物忍耐力那么高?你可能注意到了人们对于辛辣食物的忍受力You’ve probably noticed that people have wildly different tolerances, when it comes 有着很大的差异to spicy food. 你的朋友可以吃完一整碗的红辣椒 浇蘸上额外的辣汤 而你Your friend can eat an entire bowl of chili — doused with extra hot sauce — while you 或者说我 也许我们不得不把那碗东西送回厨房 然后点一碗or said me, maybe we have to send that bowl back to the kitchen, and order something little 没那么辣的less spicy. 譬如黄油面Like buttered noodles. 是什么原因导致了这种差异呢What gives? 然而 科学家们并不确定是什么让一些人狼吞虎咽的吃下哈瓦那人用洋葱做的辣调味汁Well, scientists don’t know for sure what allows some people to gulp down habanero salsa 就像喝水一样 但这里面可能混合了很多因素like it’s water, but it’s probably a mix of several factors. 一则 有些人可能仅仅是天生的对调味品没那么敏感For one thing, some people may simply be born with less sensitivity to spice. 那是因为辛辣是被一种叫做TRPV1的辣椒素受体来侦测的That’s because spiciness is detected by a sensory receptor called TRPV1. 辣椒素受体是一些蛋白质 对体温变化发生反应TRPV1 is a little protein that opens up in response to physical temperature, but also 当它和像辣椒素这样活性分子结合时也会产生反应 这也就是为什么一点墨西哥青椒就会when fiery molecules like capsaicin bind to it, which is why a bite of jalapeño will 让你的舌头感觉像是在燃烧make your tongue feel like it’s on fire. 科学家们知道产生辣椒素受体蛋白质的基因序列因人而异Scientists know that gene sequences that produce the TRPV1 protein vary from person to person, 所以它能变成稳定版本受体的几率或多或少的so it could be that certain versions of the receptor are more or less responsive than 超过其他基因others. 还有一个因素是你用了多少你的辣椒素受体There’s also the matter of how much you use your TRPV1 receptors. 许多研究表明人体有一种脱敏效果 当人们吃了Lots of studies have documented a kind of desensitization effect, while people who eat 很多使辣椒变辣的辣椒素混合物 将不得不吃a lot of capsaicin, the compound that makes hot peppers spicy, will have to eat even 甚至更多的辣椒素以品尝到同样水平的辛辣more capsaicin in order to taste the same level of spiciness. 所以 人们可能因为他们更加经常吃辛辣食物而对辛辣有更强的忍受力So, people might have higher spice tolerances because as they eat spicy food more regularly, 他们逐渐不感觉那么辣得烧了they literally aren’t feeling as much burn. 所以就用拉差辣酱来冲破对辣的忍受力极限吧So just hit it with that siracha! 另一个研究表明对于一些人来说并不是辛辣食物消耗更少 相反Another theory suggests that it’s not that spicy food burns less for some people — instead, 有些人就是喜欢那种燃烧的感觉it’s that some people like the burn. 如果你是吃玉米粉蒸肉或咖喱长大的 那你很容易学会享受If you grow up eating tamales or curry, it could be that you simply learn to enjoy the 这种感觉 因为你经常接触sensation because of repeated exposure. 或者说 这种燃烧本身可能是真正的吸引你Or, the burn itself could be the real draw. 毕竟 问道任何辣椒爱好者是否能感受到那种热量他们会很肯定的告诉你After all, ask any chili-head if they can feel the heat, and they most certainly tell 他们可以…… 那就是他们喜欢的东西you that they can… that’s what they love about it! 一个心理学家称这个现象为良性的受虐狂One psychologist calls this phenomenon benign masochism. 就像坐过山车 这是一个做危险事情的安全方法Like a roller coaster ride, it’s a safe way to do something dangerous. 有一种研究甚至将此和人格类型联系起来One study has even linked this to personality type. 在一群大多都是白人的大学生中 喜欢吃辣的人Among a group of mostly white college students, people who reported liking spicy foods were 更有可能是寻求刺激的人more likely to be sensation seekers. 所以 如果你对辛辣有很强的忍受力 可能一部分原因是你的基因 或者So, if you have a high spice tolerance, it could be partly because of your genes, or 因为你长期的饮食是塔巴斯科辣沙司而降低了你的敏感性because you’re on a constant diet of Tabasco sauce that lowers your sensitivity… 但最可能的是因为你是已经学会仅仅去享受舌头的麻刺感But it’s most likely to be because you’ve simply learned to enjoy that tongue-tingling. 感谢提问 特别感谢我们在Patreon上的赞助商Thanks for asking, and thanks especially to all of our patrons on Patreon. Patreon是一个人们可以在上面浏览并且可以给那些他们想要让其继续存在的作品投资Patreon is the site where people can go and give money to things that they want to keep 的网站existing. 所以如果你接着想要保存这些回答 或者如果你想要给我们提问So if you’d like to keep these answers coming, or if you’d like to submit questions for 让我们来回答 你可以上patreon网站或者SciShowus to answer, you can go to patreon.com/SciShow. 如果你想要帮助我们解决问题 通过及时观看我们的更新And if you wanna help us out just by watching, and watching whenever a new episode comes 我们将对此感到很高兴 希望你们也是 你可以访问YouTube网站或scishow观看out, we would love that, hopefully you would too, and you can do that by going to youtube.com/scishow 搜索来做这个and subscribe!

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