英国皇家科学院圣诞讲座：如何在太空中生存（2015）

And that's a problem,
因为当骨质流失时
because when bones start to waste,
骨密度会变小
they start to lose their mineral density,
骨头会变脆
they become weaker.
为了近距离向你们展示那种骨状态
Now, to show you what that bone looks like up close,
我们取下
uh, we've taken...
想象一下 我们从股骨颈这里
Imagine, at least, that we've taken a speck of bone
取下一小块骨组织
from the neck of that femur there,
不到一立方厘米的大小
perhaps just slightly less than a centimetre cubed,
做成模型
and made a model.
这正是我们所做的
And that's exactly what we've done.
这是一个骨模型
So this is a model of bone.
这就是从股骨颈上
This is that tiny speck from here -
取下来那很小的一块
from the neck and the femur -
放大了大约400到500倍
blown up maybe 400-500 times,
好让大家对它的结构有个认识
to give you an idea of the structure.
你也许会很吃惊
Now, you might find yourself
它竟然布满了洞
a bit surprised to see that it is full of holes.
你可能以为它应该是实心的
You might have expected it to be solid.
其实不是 因为它既要坚固又要轻便
But it's not, because it has to be strong but also light.
所以就构成了这种有趣的结构
So it's got a very interesting structure
以使它同时满足那两个要求
that makes it behave like that.
这个结构的强度不仅取决于
And the strength of the structure depends on
骨质网络的布局方式
the way that this network of bone is laid down,
还取决于我们有多少骨质
but also how much bone we have in it.
为了向大家演示
So to show you how important it is
适量的骨质很重要
to have the right amount of bone
这样你才不会骨折
so that your bones don't break,
我需要一个志愿者
I'm going to need a volunteer.
让我看一下 你来吧
Let's see... Let's have you.
到这来
Come and stand here.
-你叫什么 -卢卡 -卢卡
-What's your name? - Luka. - Luka.
卢卡 宇航员在太空时会骨质疏松
Luka, when astronauts go into space, their bones waste.
至少他们的脚跟骨 股骨颈
At least their heels, and the neck of femur,
和腰椎的骨质
and their lower back wastes
会以每月1%到2%的速度流失
at about a rate of 1-2% per month.
我们用这块骨模型
Now, what we have done is we have taken this model of the bone
模拟了它在太空中的情形
and we have simulated what would happen if we put it in space.
如果把这块骨头放入太空 卢卡
If we put that bone in space, Luka,
骨质就会流失
it would have wasted
骨密度会变小
and it would have lost some of its density.
这两块骨结构是完全相同的
It's exactly the same structure,
但这块骨质疏松
but it has wasted,
可能是因为这个人得了某种疾病
because maybe this person has a disease,
或他去过太空 懂了吗
or they have been to space. All right?
现在 为了向大家演示当骨密度变小时
Now, to show you how weak a bone gets
骨头会变得多么脆弱
when it starts losing some of its density,
我们要用到挤压盒
we've got this crusher box.
只要有足够骨质
Bone is remarkably strong
骨头就是十分坚固的
for the amount of material that's in it,
这是一块正常的骨头
and this is normal bone.
-卢卡你多重 -40到50千克
- How much do you weigh, Luka? - 40-50 kilos.
40到50千克 让我们看看会发生什么
40 or 50 kilos. All right, let's see what this is like.
你能慢慢站上来吗 好的
So will you very gently climb up on there. All right.
站稳了
And stand on that...
这个骨模型是石膏做的
Now, this model of bone is made of plaster.
然后用3D打印机打印出来
It's printed by a 3-D printer.
让我们看看它有多坚固
So let's see how strong it is.
准备好 开始
OK, ready, steady, go.
好 看来还不错
All right. So, that's pretty good.
可以下来了 卢卡
Let's take you down, Luka.
下来吧 后退一步
Let's come back down. Step down.
让我们再来试一下这个脆弱的骨头
And let's try and do the same thing with the weaker bone.
这块骨头 正如我之前所说
Now, this bone, as I've told you,
模拟了宇航员进入太空14个月
simulates what would happen if you sent an astronaut
发生了骨质疏松后
to space for 14 months
骨头的状态
and you let the bone waste.
如果你的骨密度减少了10%到15%
Now, if you lose maybe 10-15% of the density in that bone,
它的强度可能不止减小了10%或15%
you don't just get a 10% or 15% reduction in its strength.
而是变得极其脆弱
It becomes incredibly weak.
卢卡 请你再试着站上去
Now, Luka, I'm going to ask you to try and stand on this one
我们来看一下会发生什么
and we'll see how we go.
好的 慢慢来
All right, very gently on.
好 现在让我们快速倒数
OK. Now, let's have a quick countdown.
我们来倒计时
Someone get a countdown for this one.
好 三 二 一 开始
OK, three, two, one, go!
好了 卢卡 下来吧
Oh! OK. Luka, down you get.
卢卡 谢谢你帮我完成这个实验
Luka, thank you so much for helping us.
棒极了
That's fantastic.
这就是你进入太空后会发生的事
So that is what happens if you go into space.
这可是个坏消息
This is bad news.
如果你是刚返回地球或要去拜访火星的宇航员
If you are an astronaut coming back to Earth or visiting Mars,
你肯定不想从宇宙飞船下来后
what you don't want is to get off your spacecraft
因为骨头变得像这个一样脆弱
and have you break both your bones
而发现自己骨折了
because they have become as weak as this.
这就又是个问题了
And that is another problem.
非常感谢你 约翰
Thank you very much, John. Thank you.
这就是肌肉和骨头
So that's muscle and bone.
在你弃置它们
And that's what happens to them when you unload them
或不给它们荷重后 会发生的事
and you stop them having to deal with weight.
最终 身体的所有系统都会受影响
In the end, all your systems are affected.
在地球上 有一个力
And that same thing that pulls the fluid out of your head
使体液从头部流向腿部
and pushes it into your legs on Earth -
也就是重力 在太空中是不存在的
that is gravity - is absent in space.
因此体液流动方向会发生变化
And so the fluids in your body behave rather peculiarly,
这正是提姆·匹克所感受到的
and that's exactly what Tim Peake has been finding out.
让我们来看一下他在空间站的进展如何
So let's go and find out how he's getting on the space station.
我的头感觉有点胀
My head feels a little bit full.
我的体液都涌向了中心区域
All the fluid in my body has shifted up into this central area
所以多少有些胸闷
and so it's almost a little bit of a stuffy feeling,
和鼻塞的感觉
as well as if you've got a bit of a blocked-up nose.
我们来看张提姆的照片 右边是现在的样子
And so let's have a look at a picture of Tim now, on the right,
左边是升空前的样子
and him just before flight, on the left.
你会发现他的脸更圆 更浮肿了
Now, can you see his face is much rounder, much puffier?
这不是因为天上的伙食好
And that's not because there's an enormous module full of pies up there,
而是由于体液从他腿部
it's because the fluid has pushed up
涌向了头部
from his legs into his head.
这也是他会感觉胸闷的原因
And that's why he feels that stuffiness.
他们把这种
They very technically refer to
体液由下半身转移到上半身的现象
this shift in fluid from the lower body into the upper body
称之为"鸡腿"和"面部肿胀"
as "Chicken legs" and "Puffy face".
你当时也是这样吗 丹
Did that happen to you, Dan?
是 会有些
A little bit, yeah.
我见过你那时的照片
I've seen pictures of you.
你当时脸可圆了 好了
You had a really puffy face! All right.
你可以通过健身
You can protect yourself
来预防这类变化
from some of these changes by going to the gym.
宇航员们必须这么做
And astronauts have to do that.
他们必须进行大量的锻炼
They have to go to the gym a lot.
每天在健身房♥练两小时左右
They spend about two hours in the gym.
我们来看个短片
We're going to see a clip here.
这是斯科特·凯利在用高级抗阻力健身器
This is Scott Kelly on something called the ARED.
它看起来像一个举重装置
This is a machine that looks like a weightlifting machine,
宇航员们会在空间站锻炼
and they work out on the space station.
这个装置能帮他做力量训练
It allows him to do some exercise.
不是因为他们是健身狂人
It's not because these guys are fitness freaks.
他们的身材都很好 也很健康
They're all very fit and healthy,
而是因为这就像《爱丽丝梦游仙境》一样
but it's because it's like the Alice In Wonderland story.
你必须尽可能地奔跑
This is all about doing as much running as you can do
才能保持原样
just to stay in the same place.
为了像大家一样保持健康