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
2-iodoethyl alcohol
Aeg.
aftercool
air cooling type
all and all
amplitude-sensitive reflectometer
angularity cage antenna
autoinducible enzyme
bath composition
Bigabo
bioclimatic rules
born days
Bulgarus
cadmium eliminator column
catch the sun
centralish
Ceylon ruby
chitooligomer
Ciudad Piar
clinker system
communications media
coriander seed oil
Cornerville
darker shade
deck load certification
deflection signal
delivery in lighter
depth bomb
division of business
downspout conductor
Edinger-Westphal's nucleus
effective full power days
evacuation zone
evaluation standard criteria
fiddle-faddler
fixed tubesheet heat exchanger
flexicostate
float-controlled valve
fly gallery
foreplanes
forestry association
formative photography
fowler-nordheim tunnelling
Gamlan shales
geosynclinal sediments
giant daikon
goozlum
harboursome
hematoxic
hydraulic oil contamination
Ilva Mare
in loc.cit.
ingravescence
insert cutter
interference ripple
internal expanding
invt
jet-pipe oil-operated controller
keyboard display system
law of indifference
leprosed
luzula campestris dc. var. capitata miq.
lymphatic leucocythemia
maximum permissible velocity
mental workload
merrill press
modulating signal
monkey chatter
N-acetyl-3-methoxytyramine
n? ti tzu tui wu
nonapplicant
notched tappet rod
paper consumption
paranyline
paul heyses
polycyclohexyl methacrylate
Port-Royalist
prosene
qo'nos
R-UNIT
reduction apparatus
reference measuring equipment
Reykjanes
sabr
sarafs
sesame seeds
simple lathe
splendacious
spongia
state description schema
still pickling
strobe frequency
stwining stem
subradiance
swing knuckle
teratophiliacs
tierra templada
trichromatic response theory
uk theatrical
Ust'-Umal'ta
valuation vector
Voghera