时间:2018-12-30 作者:英语课 分类:英语流行话题阅读:语境识词4500


英语课

  Unit 42

Answer to the Mystery of Life Is Four

Scientists have found a simple mathematical relationship that connects the whole nature, from the tiniest cell to the vast forest of the Amazon. The connections are all based on the three dimensions of the physical world -- length, depth and width -- plus one, making the number 4. "Four is the magic number of life," says Dr. Geoffrey West of the Santa Fe Institute in New Mexico, a keynote speaker at the NZ Institute of Physics annual conference last week.

Dr. West, a British-born physicist 1, and US ecologists James Brown and Brian Enquist have found more than 50 biological relationships, such as between body size and heart rate, which are based on numbers taken to the power of 1/4.

Much of the theory is based on mathematics that can confuse the mind of anyone who struggled through School Certificate maths. Suffice to say that it centers on equations involving square roots and numbers to the power of 1/4. In simple maths, says Dr. West, "if you are 16 times bigger than your dog, your heart rate is half the dog's rate." Average body size and lifetime are also related in the same ratio. So in principle, if you are 16 times the size of your dog, you will live twice as long. We do better than that, thanks to modern medicine, but the average lifetime of pre-European Maori was around 30.

Remarkably 2, combining these two relationships means that the heart of every mammal beats roughly the same number of times in its average lifetime -- around 1.5 billion times -- regardless of whether it is a dog or a human, a mouse or an elephant. The implication is clear -- we can't beat nature. "This says that there is a maximum lifespan for a given size," Dr. West says.

He and his colleagues have found that similar "quarter-power" rules govern every kind of life on Earth, from the rate at which single-celled bacteria absorb energy to the height of those Amazon trees. They believe this uniformity is because every living thing is made up of distribution networks carrying blood, air and other nutrients 3 first through big tubes such as the aortic 4 artery 5 and then through a succession of smaller tubes to the capillaries 6, which finally distribute the nutrients to cells. Within each class of the last stage of the chain, species, such as mammals, the size of the capillaries, is the same. So are the cells that we are all made of. But as the organism gets bigger, the distribution network increases more than would be expected -- as if it had a fourth dimension. It is this increase in dimensionality that accounts for the 4. The 4 represents actually 3 + 1, where 3 is the dimensionality of the space we live in.

Auckland University physicist Dr. Peter Wills says the theory developed by Dr. West and his colleagues is widely accepted, even though it is still being developed. "There is a great deal of interest in the approach he has taken," Do. Wills said. "I don't know anybody who thinks it's nonsense."



n.物理学家,研究物理学的人
  • He is a physicist of the first rank.他是一流的物理学家。
  • The successful physicist never puts on airs.这位卓有成就的物理学家从不摆架子。
ad.不同寻常地,相当地
  • I thought she was remarkably restrained in the circumstances. 我认为她在那种情况下非常克制。
  • He made a remarkably swift recovery. 他康复得相当快。
n.(食品或化学品)营养物,营养品( nutrient的名词复数 )
  • a lack of essential nutrients 基本营养的缺乏
  • Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》
adj.大动脉的
  • The arterial pulse pressure in aortic insufficiency is widened. 主动脉瓣闭锁不全时脉搏压变宽。 来自辞典例句
  • Valvular heart disease, usually aortic and mitral insufficiency, can complicate a variety of systemic diseases. 瓣膜性心脏病,以主动脉瓣及二尖瓣闭锁不全为最常见,可使各种全身性疾病变得复杂。 来自辞典例句
n.干线,要道;动脉
  • We couldn't feel the changes in the blood pressure within the artery.我们无法感觉到动脉血管内血压的变化。
  • The aorta is the largest artery in the body.主动脉是人体中的最大动脉。
毛细管,毛细血管( capillary的名词复数 )
  • The blood flows from the capillaries back into the veins. 血从毛细血管流回静脉。
  • While Joe sleeps, a large percentage of his capillaries are inactive. 当乔睡觉时,他的毛细血管大部分是不工作的。
学英语单词
-nese
1-naphthylamine hydrochloride
abjustment
Abū Rubayq
alkalinizations
amocarzine
arctic region
autocompounded current transformer
ayyub
azatropylidene
backlog depreciation
be enveloped in
beaumontoside
by right of something
chatham str.
cold dishes
conforming imputation
contingent transaction
cross tolerance
customerinquiry
dative sickness
dehorted
delay set counter
die arrangement for continuous compaction
direct-axis transient voltage
direness
dollar value at point of exportation
doublepressing
drinkings
dropping vessel
dry salted fish
duty of assured clause
ecosophers
ego trip
eructing
face masks
faint with
femaleless
fire-bucket
flexible shaft coupling
foredated
getting away
halmyrogenic
instantaneous cut
integrand
Kaschau
kinorhyncha
kiwifruit
lecturin'
lithophile element
local transaction program
Louis III
magnetic device
measure of transcendence
mileage recorder
militarus
molybdenum complex
myohypertrophia kymoparalytica
naphthalene poisoning
octal indication
open future
open-cavity
optical fiber measurement
period-to-date quantity adjusted
phase wave
phlebodium aureums
pinch-in effect
polluter-pays
proximal point algorithm
puccinia noli-tangere
Pull your chain
pycnanthemum virginianums
rattlers
read untrue
reeling furnace
relocatable linking loader
replays
sale fees
Saxifraga divaricata
semipolitician
side action
single shot trigger
single-sideband
sinopontius aesthetascus
sizing roller
soft snap
spooneristic
steady-state heating
supporter combustion
supporting information
tambay
tetanic induced current
TLC-scanner
trentepholia (mongoma) pennipes
Truth In-lending Act
undercut slope
unimanual palpation
unshunned
vibratory hopper feeder
welders' siderosis
with (an) effort
Zǎbrani