South China's Guangdong Province to subsidize 1,000 yuan ($137) to companies that hire young people aged 16 to 24 after January 1, 2023, until December 31, in an effort to encourage the employment of young people, local authorities said in a statement on Wednesday.

Enterprises that recruit unemployed college graduates and registered unemployed youth aged 16-24, sign labor contracts and pay insurance for them will have the chance to receive subsidies, read the statement.

China announced to suspend releasing jobless data for the youth starting from August, as labor market statistics work needs improvement amid economic and social development, the National Bureau of Statistics (NBS) said on Tuesday.

The number of students in China continues to expand. In 2022, the country's population of young people aged between 16 and 24 exceeded 96 million, and over 65 million were students.

Since the main task of young people aged 16 to 24 is mastering knowledge, there are different views on whether students starting to look for jobs before graduation should be included in the labor force survey, said Fu Linghui, spokesperson of the NBS, adding that the country's statistics work and the survey and statistics of labor force need to undergo continuous improvement along with social and economic development.

Besides, China will have more than 11 million university graduates in 2023, most of whom already found jobs before graduation, Fu said citing figures from the education department, noting the rate and number of job settlements among graduates had both seen year-on-year increases.

"19 policy employment campaigns were commenced across China's state-owned enterprises and made significant progress. A series of subsidies targeting social insurance and jobs were granted to private-sector enterprises, which created 670,000 jobs for graduates," said Fu.

In addition to graduates, local authorities in Guangdong also encourage employers to actively set up positions for women with children, providing them with flexible employment options, and said that the government would provide subsidies for such enterprises.

At the same time, many places in the country, including Guangdong, are also actively supporting the development of small and micro enterprises. Guangdong said in the statement that it would encourage financial institutions to increase lending and simplify procedures for promising small and micro businesses.

According to the data from the Guangdong Provincial Taxation Bureau of the State Administration of Taxation, in the first half of 2023, Guangdong added 66.8 billion yuan in tax reduction and fee reduction and tax refund delay, of which 43.3 billion yuan was set aside for tax refund by two batches of continuous optimization and innovation preferential tax policies.

Because it plays an important role in developing the economy, expanding employment, invigorating the market, and improving people's livelihood, as the main beneficiaries of preferential tax and fee policies, micro, small and medium-sized enterprises have benefited the most, with an additional tax reduction and fee reduction and tax refund delay of 45 billion yuan, accounting for 67.37 percent.

China's urban surveyed unemployment rate stood at 5.3 percent in July, up 0.1 percentage points from June, the National Bureau of Statistics (NBS) said on Tuesday, adding that the general employment situation is stable.

Fu said unemployment issues related to university graduates will be rectified as more support measures take effect gradually, and pledged that the NBS will carry out an in-depth study and further improve labor surveys to better reflect the country's employment situation.

As Earth whips around the sun, it casts a shadow into the galaxy. If that shadow passes over cosmic neighbors that host reasonably intelligent aliens, they would see Earth the same way NASA’s Kepler space telescope sees some of them: as a periodic dip in the light from our sun. If we want to listen for alien radio broadcasts, those are the parts of the sky we should tune into, argue astronomers René Heller of the Max Planck Institute for Solar System Research in Göttingen, Germany, and Ralph Pudritz of McMaster University in Hamilton, Canada.

Within 3,500 light-years of Earth, there are 82 known stars that might host curious extraterrestrials who could detect Earth’s shadow, the researchers report in the April Astrobiology. The stars, roughly similar to or a bit cooler than the sun, encircle the solar system in nearly the same plane as Earth’s orbit — a narrow band that’s home to the 12 zodiac constellations. And these are just the stars that astronomers know about. Heller and Pudritz calculate that there could be 300,000 stars hosting 30,000 rocky habitable worlds in this sliver of the galaxy.

Since there’s a chance that the inhabitants of those worlds know about us, they might already be trying to get in touch, the researchers suggest. Even if we have no interest in an interstellar palaver, they say, we can’t hide from aliens that might see Earth silhouetted against the sun.

The 2015–2016 El Niño, one of the three strongest on record, is officially dead in the water.

More than a year after the weather-disrupting El Niño’s conception, the unusually warm seawater in the eastern Pacific Ocean has dissipated, the National Oceanic and Atmospheric Administration’s Climate Prediction Center reported June 9. During its reign, this El Niño boosted rainfall California, hastened coral bleaching and helped make 2015 the hottest year on record.

The agency estimates a 75 percent chance that El Niño’s meteorological sibling, La Niña, will take over in the coming months. La Niña conditions caused by relatively cool equatorial waters in the eastern Pacific can cause droughts in South America, heavy rainfall in Southeast Asia and can intensify Atlantic hurricane seasons.

People hooked on cocaine are more likely to stick to other habits, too. They’re also less sensitive to negative feedback that tends to push nonaddicts away from harmful habitual behaviors, new research published in the June 17 Science suggests.

The findings might help explain why cocaine addicts will do nearly anything to keep using the drug, despite awareness of its negative consequences. Instead, treatments that encourage new, healthier habits in place of drug use might click better.
Similar results have been demonstrated with mice and rats, but the effect hadn’t been well-established in humans.

There’s no pharmacological treatment approved by the U.S. Food and Drug Administration that targets cocaine addiction as there is for opioid addiction. So the best treatment currently focuses on changing patients’ behavior — and it’s not easy.

“It’s such a devastating situation for families,” says Karen Ersche, a psychologist at the University of Cambridge who led the study. Drug users “know they’ll lose their job. They’ll tell you they want to change, but still they carry on using the drug. It seems incomprehensible.”

Habits can be helpful because they free up brainpower for other things. A new driver has to think through every push of the pedal and flick of the turn signal, while an experienced one can perform these actions almost effortlessly, allowing them to also carry on a conversation. But people can also snap out of that automation when necessary, slamming on the brakes when a deer darts across the road. It’s harder for someone addicted to cocaine to get off autopilot.

Ersche and her colleagues showed sets of animal pictures to 125 people (some cocaine-dependent, others who had never chronically used drugs or alcohol). In one set of tests the participants learned through trial and error that certain responses to specific pictures would earn them points or not. In another, responding correctly let them escape an unpleasant electrical shock.
When animal pictures that once scored lots of points no longer did, the participants who weren’t using drugs adjusted to the change and were less likely to choose those pictures. Cocaine-addicted participants couldn’t adjust their behavior in the same way in light of the new information. They were also less successful at avoiding electrical shocks.

“That knowledge of something bad happening to them doesn’t really sink in,” Ersche says.

These results mirror those of another recent study showing that people with a history of drug or alcohol addiction (even though they were no longer using the substances) formed habits more easily and had a harder time changing them, says Charlotte Boettiger, a psychologist at the University of North Carolina at Chapel Hill. Boettiger led that study, published in the July Journal of Cognitive Neuroscience.

Both teams found that stimulants like cocaine seemed to influence habit formation more than other types of drugs did.

Successful behavioral treatment for cocaine addiction might take advantage of addicts’ habit-keeping tendencies, Ersche suggests.

“In some senses, the treatment community already capitalizes on this,” says Boettiger, pointing to programs that help patients replace their drug-use habits with healthier ones, like taking a walk after dinner instead of shooting up. There’s growing evidence that these strategies might work, though breaking the cycle of addiction is still tough.

Scientists don’t know whether people who form and keep habits more easily are more likely to become addicted to drugs in the first place, or whether drug addiction makes the brain more susceptible to habitual behavior. Boettiger suspects both might contribute —and that understanding the behavior and its neurological basis might someday help scientists develop medications to supplement behavior-based addiction treatments.

NEW ORLEANS — Black holes and superfluids make for strange bedfellows: One is famous for being so dense that light can’t escape, and the other is a bizarre liquid that flows without friction. But new computer simulations confirm that superfluid helium follows an unusual rule known from black holes — one with mysterious significance for physics.

Scientists demonstrated that entropy, a measure of the information contained in a system, behaves in a counterintuitive way in superfluid helium. Entropy grows at the same rate as the surface area of the superfluid helium, instead of its volume — mimicking how the entropy of a black hole grows as it gobbles up matter and expands. It’s the first time the phenomenon, known as the “area law,” has been demonstrated in simulations of a naturally occurring state of matter. Physicists reported the result March 14 at a meeting of the American Physical Society and March 13 in Nature Physics.
“If you double the size of a box, you expect to be able to double the amount of information in that box,” says physicist Christopher Herdman of the University of Waterloo in Canada. But that’s not the case for black holes. Progress toward a theory that unifies quantum mechanics and general relativity, a still thorny problem, has convinced many physicists that black holes instead follow the area law.

To demonstrate the law in a superfluid, Herdman and colleagues created a computer simulation of helium. The isotope they studied, helium-4, is the same stuff that keeps birthday balloons aloft, and it becomes a superfluid at temperatures below about 2 kelvins (–271° Celsius).

In the simulation, the researchers kept track of the helium atoms’ entanglement — quantum linkages that intertwine particles. Within the superfluid, scientists selected an imaginary sphere of the material, and studied the entanglement between atoms inside the sphere and those outside of it. That entanglement gives rise to a type of entropy in the superfluid. As the researchers increased the size of that sphere, the entropy of entanglement increased as well. The rate of increase matched that of the sphere’s increase in surface area, which grows more slowly than its volume.

The superfluid sphere is analogous to a black hole’s event horizon, the region of no return surrounding the black hole, beyond which light can’t escape. In black holes, particles on one side of the event horizon can be entangled with those on the other side, creating entanglement entropy in a similar way.

“I think it’s a fascinating result,” says physicist Joe Serene of Georgetown University in Washington, D.C. But, to advance from simulations to a measurement of entanglement entropy in real-life helium would likely be difficult. “It remains to be clear how much they can actually get out of real experimental systems,” Serene says.
This area law has outsize importance in physics. The realization that a black hole’s entropy is proportional to its surface area led to the holographic principle, the idea that the information within a region of space might be completely reproduced on its surface (SN Online: 9/8/14). Scientists hope this concept could lead to a full theory of quantum gravity, uniting the physics of the very small with large-scale gravity.

What’s more, some scientists now believe that the very structure of spacetime might be the result of quantum entanglement (SN: 5/31/14, p. 16), an idea that also grew out of the area law.

“Entanglement entropy is a concept that is successful across many different areas of physics,” says physicist Markus Greiner of Harvard University. “The big problem is no one knows how to measure that in … real-world systems.”

A new twist on gene editing makes the CRISPR/Cas9 molecular scissors act as a highlighter for the genetic instruction book. Such highlighting helps turn on specific genes.

Using the new tool, researchers treated mouse versions of type 1 diabetes, kidney injury and Duchenne muscular dystrophy, the team reports December 7 in Cell. The new method may make some types of gene therapy easier and could be a boon for researchers hoping to control gene activity in animals, scientists say.
CRISPR/Cas9 is a two-part molecular scissors. A short, guide RNA leads the DNA-cutting enzyme Cas9 to specific places in the genetic instructions that scientists want to slice. Snipping DNA is the first step to making or fixing mutations. But researchers quickly realized the editing system could be even more versatile.

In the roughly five years since CRISPR/Cas9 was first wielded, researchers have modified the tool to make a variety of changes to DNA (SN: 9/3/16, p. 22). Many of those modifications involve breaking the Cas9 scissors so they cannot cut DNA anymore. Strapping other molecules to this “dead Cas9” allows scientists to alter genes or change the genes’ activities.

Gene-activating CRISPR/Cas9, known as CRISPRa, could be used to turn on dormant genes for treating a variety of diseases. For instance, doctors might be able to turn on alternate copies of genes to compensate for missing proteins or to reinvigorate genes that grow sluggish with age. So far, researchers have mostly turned on genes with CRISPRa in cells growing in lab dishes, says Charles Gersbach, a biomedical engineer at Duke University not involved in the new study.

Being able to precisely turn on genes within an animal and influence the animal’s health is a “great advance,” Gersbach says. It has been difficult to do before because CRISPR activators are too big to fit inside viruses needed to deliver the tools to body cells.
In the new study, Juan Carlos Izpisua Belmonte of the Salk Institute for Biological Studies in La Jolla, Calif., and colleagues shrank the tool. This time, the researchers “killed” and modified the guide RNA instead of the DNA-cutting enzyme. The team used short guide RNAs, just 14 or 15 units long, instead of the usual 20 to 22.
The short leash can still lead Cas9 to specific spots in DNA, but once there, the enzyme — although still capable of cutting — doesn’t snip the DNA. Another piece of RNA tacked onto the “dead” guide attracts proteins that help turn genes on. The pieces of the dead guide activators are small enough to fit in gene therapy viruses.

In one experiment, the team wanted to restore the ability of mice with a version of type 1 diabetes to make insulin, a hormone that controls blood sugar. In type 1 diabetes, the immune system destroys the pancreas, the organ that normally makes insulin. Since pancreatic cells are gone, the researchers needed a new type of cell to take over the pancreas’s job.

So Belmonte’s group infected diabetic mice with viruses carrying the dead guide activators. The researchers used the dead guide RNAs to turn on the Pdx gene in the mice’s livers, which caused the liver cells to produce insulin, reversing the mice’s diabetes. Essentially the liver cell was transformed into one that does an important job of the pancreas.

“Labs have been trying to do that for decades,” says Kirk Wangensteen, a physician scientist at the University of Pennsylvania Perelman School of Medicine. Such experiments will help scientists understand what factors determine a cell’s identity.

But to do the gene therapy in humans, scientists would need to tackle another problem. In the diabetes experiment, they could use mice already engineered to make their own Cas9. But people don’t naturally make Cas9, and the entire dead guide activator and Cas9 system won’t fit in a single virus. So Belmonte’s team wanted to know if two viruses could be used at once to deliver all the pieces to target cells.

The Salk researchers tested their system in mice with a muscle-wasting disease that mimics Duchenne muscular dystrophy. Duchenne muscular dystrophy is caused by mutations in a huge gene called dystrophin. There’s no way to cram the dystrophin gene into a virus to do traditional replacement gene therapy, but researchers have found that turning on other genes can compensate and bulk up muscles. So in the dual-virus experiment, the scientists turned on a muscle-building gene called follistatin.

This time, the dead guide activator for turning on the follistatin gene was packaged in one virus and Cas9 in another virus. Both viruses were used to infect muscle cells in the hind legs of mice that had muscular dystrophy. Treated mice had more muscle mass in their hind legs than untreated mice did.

Much higher levels of gene activity were triggered in these experiments than scientists have achieved before, says Michael Hemann, a cancer biologist at MIT. High levels of activity are probably needed to produce enough protein to correct diseases.

Hemann and others say the new activator system will be useful for research, but some challenges remain before the therapy can be used in people. Researchers always have a challenge getting the therapy to the right place in the body, he says. The technology’s safety and efficacy must also be demonstrated.

2017 was a good year for worrying about nutrient losses that might come with a changing climate.

The idea that surging carbon dioxide levels could stealthily render some major crops less nutritious has long been percolating in plant research circles. “It’s literally a 25-year story, but it has come to a head in the last year or so,” says Lewis Ziska, a plant physiologist with the U.S. Agricultural Research Service in Beltsville, Md.

Concerns are growing that wheat, rice and some other staple crops could, pound for pound, deliver less of some minerals and protein in decades to come than those crops do today. In 2017, three reports highlighted what changes in those crops could mean for global health. Also this year, an ambitious analysis made an almost-global assessment of sources of selenium, a trace element crucial for health, and warned of regions where climate change might cut the element’s availability (SN: 4/1/17, p. 14).
Crop responses to rising CO2 might affect nutrition and health for billions of people, Ziska says, but the idea has been difficult to convey to nonspecialists. One complication is that though plants certainly need CO2 to grow, providing more of it doesn’t mean that all aspects of plant biology change in sync. In hoping for a farming bonus, Ziska warns, people often overlook the disproportionate zest of weeds. An outdoor experiment wafting extra CO2 through a forest has already shown, for example, that poison ivy grew faster than the trees.

In the 2017 Annual Review of Public Health, Samuel Myers of Harvard University and colleagues wrote that global shortfalls in human nutrition are already “staggering.” More than a billion people aren’t getting enough zinc now, raising risks of premature birth, stunted childhood growth and weak immune systems. To estimate future shortfalls, Myers and colleagues turned to nutrient data they published in 2014 in Nature.

That report compared staple crops grown in various outdoor setups on three continents at either ambient or enhanced atmospheric CO2 concentrations. Fancy research piping boosted ambient levels of 363 to 386 parts per million to 546 and 584 ppm. (A moderate scenario puts late-century levels at 580 to 720 ppm.)
Decreases in zinc concentrations, including in rice and wheat, could plunge an additional 150 million to 200 million people into zinc deficiency, the researchers calculate. Likewise, predicted declines in iron content in some grains and legumes look worrisome for countries with anemia rates already higher than 20 percent, such as India and Algeria, Myers and colleagues reported in August in GeoHealth. Such high-anemia nations have a lot of people especially at risk, including 1.4 billion young children and women of childbearing age.

An expanded set of experiments suggested that protein content in rice and wheat could sink by roughly 8 percent, Myers and colleagues wrote in the August Environmental Health Perspectives. Thus, rising CO2 could add some 148 million people worldwide to the roughly 1.4 billion expected to be short of protein by 2050.

Also this year, grazing cattle joined the list of animals facing a protein downturn in their food. (Ziska and colleagues raised the issue for bees in 2016.) For cattle, 22 years and more than 36,000 fecal measurements suggest that plants on U.S. grazing lands have grown poorer in protein, ecologist Joseph Craine of Jonah Ventures, in Boulder, Colo., and colleagues reported April 10 in Environmental Research Letters. For every kilogram of plants that cattle ate in 2015, there were 10.6 grams less protein than there had been 22 years before. The yearly loss is equivalent to the protein available in $1.9 billion worth of soy meal — and rising CO2 is a possible culprit.

Plant reactions will be varied and complex, Ziska points out. An Artemisia plant’s anti-malarial compound, artemisinin, can get more concentrated as CO2 increases, possibly good news for plant-based medicine. But the mix of urushiols, oils that put the itch in poison ivy, can become more allergy-provoking when exposed to extra CO2, a test suggested. Ziska is now looking into how much caffeine will turbocharge future coffee beans.

Whatever the changes, concern is growing, says mathematical biologist Irakli Loladze of Bryan College of Health Sciences in Lincoln, Neb. He, Ziska and nine coauthors included nutritional erosion in the 2016 U.S. scientific assessment of the impacts of climate change on human health. To raise the public profile of the issue, though, Myers says, “We have a ways to go.”

An itinerant interstellar asteroid may actually be a comet in disguise.

Known as ‘Oumuamua, the object was detected in October and is the first visitor from another star spotted touring our solar system (SN: 11/ 25/17, p. 14). Early observations suggested the vagabond was rocky. But after additional analysis, a team of researchers suggests December 18 in Nature Astronomy that the object might have an icy core.

In general, comets are icy and asteroids are rocky. Ice gives comets their characteristic tails: As a comet passes near the sun, the heat warms the ice, causing it to sublimate, releasing gas and dust. Because no tail appeared despite ‘Oumuamua’s passage by the sun, the mysterious visitor was dubbed an asteroid — a surprising conclusion since the vast majority of objects ejected from star systems are expected to be icy.
“Everybody’s been assuming that this is just a lump of rock,” says astronomer Alan Fitzsimmons of Queen’s University Belfast in Northern Ireland. “This may not be the case.” So ‘Oumuamua might not be as odd as originally thought.

Fitzsimmons and colleagues used the Very Large Telescope in Chile and the William Herschel Telescope in La Palma, Spain to capture the object’s spectrum — its light sliced up according to wavelength. “It’s an impressive piece of work,” says astronomer Olivier Hainaut of the European Southern Observatory in Garching, Germany, who was not involved with the research. “It was a very faint object and to observe such a faint moving target is horribly difficult.”

The object’s spectrum revealed a reddish hue with no signs of ice. But ‘Oumuamua could have an exterior crust — about half a meter thick or thicker — which hid the ice and insulated it from the sun’s heat, the researchers calculated. “You could have a lot of ice in this thing and really not know it,” says astronomer Jessica Sunshine of the University of Maryland in College Park, who was not involved with the research. Such a crust could have formed as energetic particles known as cosmic rays bombarded the object over its lifetime, creating an ice-free surface rich in organic compounds. ‘Oumuamua’s spectrum is similar to those of other objects in the solar system suspected of concealing such icy interiors.
Studies of ‘Oumuamua continue — with some researchers looking for evidence of even more surprising hypotheses. Using the Green Bank Telescope in West Virginia, scientists with the Breakthrough Listen project are searching for signatures of artificial origin — that is, aliens — on the off chance that the object might be an interstellar spacecraft. Sorry, X-Files fans: So far no such signals have been detected.

Some reports from 2017 hint at potentially big discoveries — if the research holds up to additional scientific scrutiny.

Under pressure
Putting the squeeze on hydrogen gas turned it into a long-elusive metal that may superconduct, Harvard University physicists claimed (SN: 2/18/17, p. 14). A diamond vise, supercold temperatures and intense pressure made the element reflective — a key property of metals. But other researchers in the field don’t buy it; one experiment with a slew of caveats isn’t enough to confirm the claim, those scientists say.
Woman warrior?
The skeleton of a 10th century Viking woman buried in full warrior regalia has scientists sparring over women’s roles in Viking society (SN: 10/14/17, p. 6). Researchers who confirmed the skeleton’s sex through DNA analysis contend that the woman was a high-ranking Viking warrior, the first Viking woman warrior known. But other archaeologists argue that the bones — with no obvious signs of injury or strenuous physical activity — are too pristine to have seen battle.
A far-flung star’s extra wink, spotted in data from the Kepler space telescope and further probed by the Hubble Space Telescope, may be the first evidence for an exomoon — a moon orbiting a planet orbiting a distant star. If it exists, the Neptune-sized candidate moon (dubbed Kepler 1625b i) is roughly 4,000 light-years away and orbits a planet a tad larger than Jupiter (SN: 8/19/17, p. 15).

Rooting out hominid origins
The first members of the human evolutionary family may have originated in Europe, not Africa. New analyses of a fossilized jaw (shown) and teeth from Graecopithecus, a chimpanzee-sized primate that lived in southeastern Europe roughly 7 million years ago, suggest that it may be the earliest known hominid (SN: 6/24/17, p. 9). But more complete fossils are needed to determine whether Graecopithecus was truly a hominid.

SAN FRANCISCO — Even moderate light pollution can roughly double the time a house sparrow remains a risk for passing along the worrisome West Nile virus.

House sparrows, about as widespread across the United States as artificial lighting itself, make a useful test species for a first-of-its-kind study of how night illumination might contribute to disease spread, said Meredith Kernbach, an eco-immunologist at the University of South Florida in Tampa. Passer domesticus brought into the lab and kept dimly illuminated at night were slower in fighting off West Nile infections than lab sparrows allowed full darkness, Kernbach reported January 7 at the annual meeting of the Society for Integrative and Comparative Biology.
Sparrows kept under a dim night light typically had enough virus in their bloodstreams for at least four days to turn biting mosquitoes into disease spreaders, she said. Sparrows housed in darkness had high virus concentrations for only about two days. Doubling the time a bird can pass along a big dose of virus could in theory increase the likelihood that a disease will spread.

The broader question of whether light pollution affects human health has been a concern for shift workers. Researchers have also looked at possible changes in reproduction and other behavior in wildlife (SN: 12/26/15, p. 29).

Kernbach’s project opens new territory by testing the effects of light on physiological factors that control how diseases that can infect humans might hopscotch among animals, says Jenny Ouyang, of the University of Nevada, Reno. As light pollution studies go, “I don’t know of anything like this,” says Ouyang, an integrative physiologist who also has studied light pollution and birds.

The tests intensify Ouyang’s curiosity about whether light might affect the spread of malaria among humans. There have been hints and speculation in the scientific literature, she says, that vector mosquitoes might be drawn to light sources in some circumstances, which could mean that excess illumination might compound urban disease risks.
Kernbach based much of her lab test on real-world conditions. The viral dose she gave the birds was strong enough to kill about 40 percent of them, and it was well within what a mosquito might pick up vampirizing birds or mammals. She used white incandescent lighting, basically the last century’s universal light bulb, which is still common despite inroads by LED lighting.

The white incandescence in the experiment has plenty of warmer tones, but does include some of blue wavelengths from common cool white LEDs, or light-emitting diodes. The sparrows on average experienced about 8 lux of this white incandescence during their seven-hour nights. (A heavily overcast day, by comparison, ranks at about 100 lux.)

Other studies in birds are showing that artificial night lighting can affect concentrations of the hormone corticosterone, which helps orchestrate reactions of the immune system. But Kernbach said she found no signs in her experiment that corticosterone controlled the results she saw in house sparrows.

What lights do to the birds is only part of the story, points out Davide Dominoni, an eco-physiologist at the Netherlands Institute of Ecology in Wageningen. Researchers will also need to look for effects on the virus itself. And on the mosquitoes.