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 walking skeleton
a-except-b gate
administrative detainees
adoxograph
air balloon
aluminium profile polishing machine
asebotin
Atomic Hydrogen Weld
baia delle zagare
bowed handle
brake beam safety chain eye
bust caps
Celendin
center front point
conjugate kernel
contingent depreciation
continuous wave magnetron
copulist
credit issue
Cumberland I.
danakils
dishouse
docent
driving gear bush speedometer
electropneumatic valve positioner
emergency power
experimental computer network
face painting
fatherliness
feed with
fine grinder
flat screen printing machine
flight-path recorder
flights of stairs
forward biassd p-n junction
genus crexes
geratic period
green chalcedony
Grimentz
grippen
Guerissa
H-like ion
Hamasaka
higher-levels
incorporate in/into
internal exposure reference dose
interpretation of Kuhn-Tucker conditions
jannett
job control task
Kioga
laser gasification
mafalda
Mechlin
mercurial lamp metal-film resistor
miarolite
mithridates the greats
motor generator arc welder
multi-object spec-trograph
multilanguage processor
nannyberry (vibernum sp.)
Noflame
non-numeric operation
non-separated topological group
oil and fat product
opp film
Ownership-specific advantages
paraumbilical veins
pass-outs
paving seam
personal bankruptcy
Pilea bracteosa
plain concrete
posterior wall colporrhaphy
pressure zone
production sampling tests
proximate composition
pure chance call
queued control
radiobeacon in general
remated
repititional regeneration
ronggengs
sao franciscoes
scouting tank
sea-bird
sea-kale
sequential index access command
shelbyville
singing propeller
soft-seller
state-assisted
Tanzawa-san
terminal office
thick-walled pod
thumb war
thumbshots
Trichobilharzia gigantica
twilight brightness
upper rail
uricoxidase
winterhome
zollar