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
aeroshell
animal husbandries
apwu
as clear as noon
Asian country
ass's-ear
aural zero
bejabers
bend one's knee to
Bol'shoye Yanikovo
books of obadiah
breaker roll type oil seed press
brush sander
Carex rochebrunii
catalytic cycle
Cefradine-Xincat
chlamys vesiculosa
chrysamine
cinepazate
cobblerss
competitive coupler
compression-to-traction
converse
credit-token agreement
cross hair
crush hat
cycle welding
cyclopean masonries
cyclopropylamine
dawn star
Department of Education and Science
depigmented
emission of light
endocardiac
envision
equivalent roughness
eucaryotic organism
euonymus euscaphis hand-mazz.
expanded bed
extrudate expansion
ferias
full-dress
gastric groove
general expenditure
get under sail
glucothiose
gnomish
guide bend test
half hourly
hanging out with
healthy environment
hydromatic retort
ISCS
kemppi
kiboshing
knife edge felt wheel
majority opinion
Malayali
MapDraw
marcocci
ministage
narcobourgeoisie
not care a cuss
nucleus olivaris cranialis
nunchucks
oven flow
oxyhalogenation
pathogenicity rate
peribiliary
photoreceptors
PPHK
Protagorean
red-earth
relation between cause and effect
Riggs, Bobby
ring technique
rotary type cam-driven tableting press
ryfly
saury pike
seal with annular groove
sell us
single valve receiver
single-slag operation
solid system dynamics
spiral chuck
spiral thread of trachead tube
sprayed insulation
strain resolution
strip-film camera
structural factor
syncongestive
tetrabutyl urea
thermal conduction per unit area
Thurley
tilemap
timber work
toeoff
tokenlike
Ukrainianizing
uninjuring
unrivet
unwaterlogged