时间:2018-12-24 作者:英语课 分类:2017年Scientific American(二)月


英语课

 


Time spent in zero G changes the body: Astronauts come home with bone loss and muscle weakness. But what happens in their heads? To find out, researchers examined MRI’s of astronauts’ brains taken before and after flight. They looked at 12 astronauts who spent two weeks on the shuttle crew and 14 who spent half a year on the International Space Station.


What they saw is that the spacefarers’ gray matter appeared compressed…particularly around the front and sides of the brain and the area around the eyes. That’s probably due to a redistribution of cerebrospinal fluid, which is no longer being pulled down by gravity, the researchers say. 


The exception to this compression is in a small area of the brain that controls the feeling in, and movement of, the legs. This region expanded in the astronauts—particularly the ones who spent six months circling the earth. That change, the researchers say, could reflect the formation of new neural 1 connections as the brain tries to adapt to the weightless conditions. The study is in the Nature partner journal Microgravity. [Vincent Koppelmans et al., Brain structural 2 plasticity with spaceflight]


The findings could have applications back here on terra firma. For example, we could learn more about treating the brain changes that take place in people who are on extended bedrest, with their feet elevated and thus higher than their heads.


The brain change is yet another thing that future space travelers, like those that may someday head to Mars, should keep in mind. No matter what size that mind may be.


—Karen Hopkin 



1 neural
adj.神经的,神经系统的
  • The neural network can preferably solve the non- linear problem.利用神经网络建模可以较好地解决非线性问题。
  • The information transmission in neural system depends on neurotransmitters.信息传递的神经途径有赖于神经递质。
2 structural
adj.构造的,组织的,建筑(用)的
  • The storm caused no structural damage.风暴没有造成建筑结构方面的破坏。
  • The North American continent is made up of three great structural entities.北美大陆是由三个构造单元组成的。
学英语单词
A.C.asynchronous motor
aethylis chloridum
anti-skid control
appetise
Arbutus uva-ursi
assessors
automatic slat
bas reliefs
base operand
bay head beach
binocular observation
cataphatism
Chelidonium majus
chicken-wing
chromium(iii) iodide
cleavage poor
common bird cherry
compact algebraic group
compressed air press
construction trust
Crép-en-Valois
cyclic parthenogenesis
deep v stem
developmental biology of prokaryotes
dispersed learning
display units
drunk in
duct carcinoma
dystrophic water
excuser
exp. exit permit
extra-tropical
ezell
f'ing
ferric rhodanide
finder telescope
flat-screen TV
gating system plan
giudice
glassfibre reinforced polyester resin
gruenbaum
gusty wind
Guyenne
hand reamer
heavy sections
hemispheric sulcus
hittiter
househunts
hover performance
imaginary places
imperforated hymen
in the course
included slag
incoherent speech
income standstill policy
intelligent test
Jeduthun
judgement for the plaintiff
junction nevus
Khmer script
kidbrooke
kwailo
lawn sprinkler
limit of telephone transmission
Markets in Financial Instruments Directive
matel
medicos
mid-ocean canyon
miniclimaxes
nuttily
oratorios
outward unit normal vector
Panimycin
Paraxonia
photo electron spectroscopy
plasma desmearer
postcolonic gastrojejunostomy
pressure-sensitive diode
Prudentopolis
rauthe
recumbent fold trap
reflection invariance
server status
Setian
sialith
single output function
situational intimacy
social-chauvinism
soft vinyl
spilsbury
superintends
superparasite
take the position
take the shine off
temperature tester
transferred position line
turfy
vertical constitution
virtual realities
wraak
yarls
Zechstein(series)