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 suspicion of
after deck house
Allmendingen
alveolar region
annealed strip
antidiuretics
apophysiary point
asphalt cemented ballast bed
baling hoop
bear someone company
Belasovka
bifaciatus
blood-CSF barrier
canal mud
chaldeas
chlidanthine
circular arc gear
color graphic monitor
crisis action planning
dealing room
debouches
DIG-BIL
economic base theory
external teeth serrated lock washer
financial forecasts
flat drive
flowed energy
gas tank truck
greyest
haemoglobinuric
Hawkins County
horse riding
hypophyseal-duct tumor
IAIS
industrial controlling
kollophan (collophane)
labor insurance salary
landrums
latin letter
lead(iv) hydroxide
less important work
linear scale ohmmeter
linkage check chain
low pressure gas cylinder
Madhya Pradesh, State of
malli
mercaptans
metals/financial notices
Minh Son
montanic acid
neutral fix-point
Nicotiana tabacum var.anguseifolia
nive
non-spontaneous mutation
nonscriptural
osbeckia crinita benth.
over-indexed
Ped.D
percolation transition
phenylhydrazine levulinic
phylogenetic morphology
pompine
porcelain enameling sheet
potassium acid tartrate
pr-positive
prakticas
pressed-steels
pressure distribution of foundation
primary nitro-compound
read write system
recolonizes
red - hot news
renin-angiotensin system
reserved land
risibility
Risoux, Mt.
rullion
schizogamy
self alienation
shingle structure
skerrett
space-like surface element
strait-laceds
subhaploid
substantia hyalina
sufferante
terminal-banding
termitocole
timber deck
tolazoline hydrochloride
tollbooth
TPI-1
trigger bar
turbine oil
unerwater-surveillance system
uninvitingness
v. lingualis
vacuum tuberculin
velocity skew
venture forth
Wertheim's Ointment
wheel load capacity