时间:2018-12-24 作者:英语课 分类:2017年Scientific American(一)月


英语课

 


Last time you hit the beach—and yeah, probably seems like a distant memory in the currently chilly 1 parts of the world—did you pack sunscreen? A beach umbrella? Or both?


Researchers put the two sun-protecting products to the test. First contender: a beach umbrella, which they evaluated with a spectrophotometer to see if UV rays passed through. They didn't…good sign so far. The second contender was sunscreen: 100 SPF.


Then the scientists rallied 81 people to go sunbathing 2 at a lake outside Dallas, for three hours around mid-day. Half got beach umbrellas. The other half, all-you-can-apply sunscreen. And because this is science—not a day at the beach, eh, let me rephrase that, not a walk in the park—the participants were not allowed to take a dip.


Twenty four hours after the solar exposure—enough time for any sunburns to ripen—the researchers visually inspected the sunseekers' skin. And they found that three times as many umbrella-sitters had sunburns somewhere on their bodies, compared to their sunscreen-slathering neighbors. And since the umbrellas themselves block UV rays, the burns are likely due to UV light bouncing off the sand and other surfaces, then hitting unprotected skin. The study is in JAMA Dermatology. [Hao Ou-Yang et al., Sun Protection by Beach Umbrella vs Sunscreen With a High Sun Protection Factor A Randomized Clinical Trial]


The caveat 3? Even sunscreen users weren't completely burn-free. So the researchers—some of whom, full disclosure, work at Johnson & Johnson, which makes sunscreen—instead recommend hedging your bets. Wear a wide-brimmed hat. Sit in the shade. Use sunblock, too. To ensure you don't need that fourth strategy: aloe vera.


—Christopher Intagliata



1 chilly
adj.凉快的,寒冷的
  • I feel chilly without a coat.我由于没有穿大衣而感到凉飕飕的。
  • I grew chilly when the fire went out.炉火熄灭后,寒气逼人。
2 sunbathing
n.日光浴
  • tourists sunbathing on the beach 在海滩上沐浴着阳光的游客
  • We've been sunbathing on the beach. 我们一直在海滩上晒日光浴。
3 caveat
n.警告; 防止误解的说明
  • I would offer a caveat for those who want to join me in the dual calling.为防止发生误解,我想对那些想要步我后尘的人提出警告。
  • As I have written before,that's quite a caveat.正如我以前所写,那确实是个警告。
学英语单词
a bar of chocolate
achilleic acid
age- earnings profile
AM Her binary
amino acid pattern
appledura
aspires to
authorized program facility
baers
Batuata
belegar
biograft
boxing
brushing electroplating
bullaries
butterworth-heinemann
cargo handling by gravity
center ice
central cylinder
centre-run mould
chun-lee
construction surveying
coordain
corails
Cori ester
DISC assessments
discharge of fluid
encephalomere
fluorocarbon plastics
Flying Spaghetti Monsterism
foodlessness
fur-effect fabric
glyceritum guaiaci
hdcopy
headfucks
high-temperature creep
Hookdale
Ireko
iverye
juniata
knudsen region
latent trait theory
LDMS
lead a fast life
log-log range
logging technique
loose egg
lumbosacral radiculitis
mago
manganous dichloride
mastard
mru (mobile radio unit)
N-acetyl-D-galactosamine
natural gas tank
noise attenuation duct
nonpaying
occidental cat's-eye
open coil annealing furnace
pergelic
physics of planetary interior
piermarini
plant shoot
polich
presidential Medal of Freedom
pressure-biased valve
primitive recursive
Puntagorda
rastergram
rattel
raveyne
reduction method
Rothmund's syndrome
Rājāhar
semipositone
seocndary pollutant
service-producing
space planning
sphenoid of the first order
spinnlers
stock savings bank
stock-markets
sussex
suturae primosecundaria
systematic convergence error
tarsal pad
tengmalms
the Great War
thiolin sodium
Time Warner
transitional motion
translate phase
tub bath
tubulo-
undulatory movements
unfashionableness
uniform ensemble
unpointedness
unwinding of loop
uranophane (uranotile)
voice band compressor
Wadai
windy cities