Particle Physics
Adrian Cho
This month, in a cavernous laboratory 1.4 kilometers beneath Italy's
Apennine Mountains, physicists will begin filling a cylindrical tank
with frigid liquid xenon. The tank is the heart of XENON 1 Ton
(XENON1T), the biggest detector so far to hunt for weakly interacting
massive particles (WIMPs): hypothetical particles that may make up dark
matter. But even as XENON1T gears up to begin taking data, researchers
are starting to have doubts about the concept of WIMPs. A few years ago,
when the biggest WIMP detector weighed a few kilograms, most thought a
1-ton experiment would either find WIMPs or stick a dagger in the idea.
But generations of ever bigger detectors have come up empty, and
physicists are rethinking the argument for WIMPs and what it might take
to find them. They have
bigger detectors in the works and are laying plans for the ultimate
WIMP detector. But even avid dark matter hunters aren't sure that giant
detector is worth pursuing.
Infectious Disease
Gretchen Vogel
Since the Zika virus began racing through the Americas, scientists
have been trying to figure out when and where it entered Brazil, where
it was first detected in March 2015. Speculation has focused on the
influx of fans for the World Cup in June and July 2014, or for a
championship canoe race in September 2014. But a new genome analysis
suggests the virus had likely been spreading there long before either
event, having arrived sometime between May and December 2013. It could
have arrived during the Confederations Cup soccer tournament in late
June 2013, the authors say. That event brought the Tahitian national
team to a stadium in Recife, near the epicenter of the Brazilian
epidemic. But that was several months before cases of Zika were reported
in Tahiti, and the authors think it's
more fruitful to look at broader travel patterns rather than discrete
events. They point out that during 2013, air travel from Zika-endemic
areas to Brazil increased by almost 50%, from roughly 3500 passengers
arriving per month to nearly 5000.
Evolution
Amy Maxmen
Several unprecedented videos of gelatinous sea creatures called comb
jellies, or ctenophores, now threaten to upend the standard view of the
evolution of the so-called through-gut. Comb jellies, jellyfish, sea
sponges, and a few other creatures all were thought to lack an anus,
which meant they had to eat and defecate through a single hole. These
are descendants of some of the first animals to arise, so it has been
thought that the through-gut and anus were an innovation that came after
those lineages emerged-and perhaps something that drove the diversity
of new animal forms. But on 15 March, at the Ctenopolooza meeting in St.
Augustine, Florida, evolutionary biologist William Browne of the
University of Miami in Florida debuted films of comb jellies pooping-and
it wasn't through their
mouths. Browne's videos elicited gasps from the audience, who is now
rethinking when the through-gut first evolved-and whether it may have
emerged more than once.
Synthetic Biology
Robert F. Service
When it comes to genome size, a rare Japanese flower, called Paris japonica
, is the current heavyweight champ, with 50 times more DNA than
humans. At the other end of the scale, there's now a new lightweight
record-holder growing in petri dishes in southern California. This week
in Science
, researchers led by genome sequencing pioneer Craig Venter report
engineering a bacterium to have the smallest genome-and the fewest
genes-of any freely living organism, smaller than the flower's by a
factor of 282,000. Known as Syn 3.0, the new organism has a genome
whittled down to the bare essentials needed to survive and reproduce,
just 473 genes. The microbe's streamlined genetic structure excites
evolutionary biologists and biotechnologists, who anticipate adding
genes back to it one by one to study their effects. "It's a tour de
force," says George Church, a synthetic biologist at Harvard University.
Q&A
John Bohannon
After Kurdish separatists set off a car bomb Turkey's capital last
week, killing 37 people, Turkish President Recep Tayyip Erdoğan
announced that the definition of "terrorism" should be expanded to
include all who provide support in the form of "propaganda" and
specifically called out academics. Within hours of the president's
speech, police arrived at the homes of four Turkish researchers who had
signed a petition calling for peace. Three are now imprisoned; Turkish
academics fear that many more arrests will follow. Science has interviewed one who eluded arrest: Meral Camcı, a literary scholar who had gone to France on vacation.
China
Hao Xin
China's economic slowdown could bring a windfall for basic science.
Cosmic evolution, the structure of matter, the origins of life, and
understanding how the brain works all deserve strengthened support,
according to China's latest 5-year development plan, which could triple
funding for basic research by 2020. An outline of the plan, which covers
2016 through 2020, received pro forma approval by the National People's
Congress on 16 March at its closing session. Though details are still
scarce, one expectation is that funding for basic research will rise to
10% of total R&D spending by 2020, up from less than 5% now. If the
10% goal is achieved, investment in basic research could hit 225 billion
yuan, or about $34.5 billion, in 2020, compared with last year's $10
billion.
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