Are you someone who will happily spend days sprawled on your sofa watching TV? Or could you sit in the same spot for hours with only a computer game for company? If you answered yes to any of the above questions, then the future of human space travel could rest with you. Nasa is recruiting volunteers to lie a bed for 70 days to research the effects of microgravity on the human body. And the study, which is on-going, will give you around £3,137 ($5,000) a month for the pleasure. The study takes place at the Johnson Space Centre in Houston where you stay for two weeks, doing every day activities, so that scientists can monitor your body in normal conditions. You then spend 70 days in a tilted bed where you will have light for 16 hours per day and darkness for eight hours per day. Access to computer games, TV, books, the internet and visitors is permitted, and all food is provided to keep you at a constant weight. You can even get a shower while you’re in bed. The only time you can move is when scientists carry out tests to find out any changes in bone, muscle, circulation, nutrition and the immune system. Or as part of the newly-introduced exercise called the ‘countermeasure and function testing’ study, that will monitor how different movements can effect muscle size and strength, bone health, and cardiovascular function. Even then you will be lying in bed and will exercise on specially-designed equipment. Following 70 days, there is a 14-day rehabilitation period to get your body back into shape. If all this sounds like your dream come true, applications can be made here. Self-described ‘pillownaut’ Heather Archuletta has taken part in the study three times. ‘I'm a very active person, so it's difficult to be restricted to bed sometimes, but many of us are willing to do it for the sake of future space exploration,’ she wrote on her blog. ‘The... money... is... pretty freaking awesome, however. About $5,000 per month, which is great if you've just graduated, can't find a job, are between jobs, or just plain love space exploration,’ added Ms Archuletta. A similar study is being undertaken by the European's Space Agency's (ESA) Programme for Life and Physical Sciences at the Medes Institute in Toulouse, France. But while it may sound like easy money, it isn’t the walk in the park that it might first seem. During extended periods, microgravity takes a serious toll on the human body. Without the pulls of normal gravity, blood doesn't flow downhill, but pools in the extremities including the face, hands and feet, causing a puffy appearance. And without that downward pressure, height increases. Body mass often decreases with a loss of muscular tissue from nitrogen depletion; the veins and arteries of the legs become weaker, anaemia occurs, accompanied by a reduction in blood count. The most serious concern is the loss of bone calcium that increases with the length of a mission. The calcium loss from bones subjected to extended microgravity takes place at 10 times the rate of an elderly person suffering from osteoporosis. Astronauts report an overall feeling of weakness and loss of balance upon return to Earth, though recovery is nearly complete after a week. Researching the effects of microgravity has been an on-going programme at Nasa for the past 25 years. There are a number of other ways to create low-gravity environments on Earth for research, but these last for short periods of time. For instance releasing experiment samples from tall drop towers provides about four seconds of microgravity. Research aircraft can expose experiments to about 30 seconds of low-gravity while the aircraft approaches the top of a steep climb and begins a sharp descent.
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你喜歡整天躺在沙發(fā)上看電視嗎?愿意坐在一個(gè)地方玩上數(shù)小時(shí)的游戲嗎?如果答案是肯定的,那么恭喜你,你可以申請(qǐng)成為美國(guó)航空航天局的志愿者了。 據(jù)英國(guó)《每日郵報(bào)》9月16日?qǐng)?bào)道,美國(guó)國(guó)家航空航天局(NASA)正在招聘臥床70天的志愿者,用以研究微重力對(duì)人體的研究。志愿者將獲得每個(gè)月5000美元左右的報(bào)酬。 這項(xiàng)研究在休斯敦的約翰遜航天中心進(jìn)行,志愿者將在那里待上兩周,做一些日?;顒?dòng),讓科學(xué)家檢測(cè)其在正常情況下的身體狀態(tài)。 接下來(lái),志愿者將在一個(gè)傾斜的床上躺上70天,每天有16個(gè)小時(shí)可以見(jiàn)到光,另外8小時(shí)則要在黑暗中度過(guò)。當(dāng)然,你可以玩電腦游戲、看電視、看書(shū)、上網(wǎng)、會(huì)客,獲得定量的食物供給,甚至可以在床上淋浴。 然而,只有在研究人員前來(lái)檢查骨頭、肌肉、血液循環(huán)、營(yíng)養(yǎng)和免疫系統(tǒng)的變化時(shí),志愿者才能移動(dòng)。即便在那個(gè)時(shí)候,志愿者也只能躺在床上,并接受特制設(shè)備的檢驗(yàn)。 70天后,志愿者會(huì)接受一個(gè)14天的康復(fù)期,讓身體恢復(fù)正常。 三次參加該實(shí)驗(yàn)的希瑟?阿楚萊塔在博客上寫(xiě)道:“我是一個(gè)很活躍的人,所以被困在床上很難受。但是很多人都愿意為了未來(lái)的太空探索去做這個(gè)實(shí)驗(yàn)。報(bào)酬還是很豐厚的,大約5000美元一個(gè)月。如果你剛畢業(yè),找不到工作,剛辭去上一份工作又沒(méi)找到下家,或者僅僅是熱愛(ài)太空探索,都可以去報(bào)名參加?!?/p> 盡管聽(tīng)上去很容易,但該實(shí)驗(yàn)絕不像在公園散步那么簡(jiǎn)單。長(zhǎng)期看來(lái),微重力會(huì)對(duì)人體產(chǎn)生嚴(yán)重不良影響。血液無(wú)法往下流,而是停留在臉部和手足等處,造成浮腫;肌肉組織會(huì)隨著氮源的消耗而減少,體重隨之減輕;腿部的靜脈和動(dòng)脈變?nèi)?;隨著血細(xì)胞減少,將出現(xiàn)貧血癥狀;骨鈣大量流失。 微重力是指重力或其它的外力引起的加速度不超過(guò)10e-5~10e-4g。太空環(huán)境就是微重力環(huán)境。據(jù)報(bào)道,NASA在過(guò)去25年里一直在研究微重力的影響。 相關(guān)閱讀 2014全美大學(xué)排行榜出爐 普林斯頓大學(xué)登頂 英大學(xué)生注冊(cè)表公開(kāi)調(diào)查學(xué)生性取向 美方對(duì)敘軍事打擊將持續(xù)3天 或動(dòng)用航母戰(zhàn)斗群 (譯者 信蓮 編輯 王輝) |
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