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For more than a decade, astronomers have searched for planets orbiting AU Microscopii, a nearby star still surrounded by a disk of debris left over from its formation. Now scientists using data from NASA's Transiting Exoplanet Survey Satellite (TESS) and retired Spitzer Space Telescope report the discovery of a planet about as large as Neptune that circles the young star in just over a week.

The system, known as AU Mic for short, provides a one-of-kind laboratory for studying how planets and their atmospheres form, evolve and interact with their stars.

"AU Mic is a young, nearby M dwarf star. It's surrounded by a vast debris disk in which moving clumps of dust have been tracked, and now, thanks to TESS and Spitzer, it has a planet with a direct size measurement," said Bryson Cale, a doctoral student at George Mason University in Fairfax, Virginia. "There is no other known system that checks all of these important boxes."

The new planet, AU Mic b, is described in a paper co-authored by Cale and led by his advisor Peter Plavchan, an assistant professor of physics and astronomy at George Mason. Their report was published on Wednesday, June 24, in the journal Nature.

AU Mic b is featured in a new NASA poster available in English and Spanish, part of a Galaxy of Horrors series. The fun but informative series resulted from a collaboration of scientists and artists and was produced by NASA's Exoplanet Exploration Program Office.

AU Mic is a cool red dwarf star with an age estimated at 20 million to 30 million years, making it a stellar infant compared to our Sun, which is at least 150 times older. The star is so young that it primarily shines from the heat generated as its own gravity pulls it inward and compresses it. Less than 10% of the star's energy comes from the fusion of hydrogen into helium in its core, the process that powers stars like our Sun.

The system is located 31.9 light-years away in the southern constellation Microscopium. It's part of a nearby collection of stars called the Beta Pictoris Moving Group, which takes its name from a bigger, hotter A-type star that harbors two planets and is likewise surrounded by a debris disk.

Although the systems have the same age, their planets are markedly different. The planet AU Mic b almost hugs its star, completing an orbit every 8.5 days. It weighs less than 58 times Earth's mass, placing it in the category of Neptune-like worlds. Beta Pictoris b and c, however, are both at least 50 times more massive than AU Mic b and take 21 and 3.3 years, respectively, to orbit their star.

"We think AU Mic b formed far from the star and migrated inward to its current orbit, something that can happen as planets interact gravitationally with a gas disk or with other planets," said co-author Thomas Barclay, an associate research scientist at the University of Maryland, Baltimore County and an associate project scientist for TESS at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "By contrast, Beta Pictoris b's orbit doesn't appear to have migrated much at all. The differences between these similarly aged systems can tell us a lot about how planets form and migrate."

Detecting planets around stars like AU Mic poses a particular challenge. These stormy stars possess strong magnetic fields and can be covered with starspots -- cooler, darker and highly magnetic regions akin to sunspots -- that frequently erupt powerful stellar flares. Both the spots and their flares contribute to the star's brightness changes.

In July and August 2018, when TESS was observing AU Mic, the star produced numerous flares, some of which were more powerful than the strongest flares ever recorded on the Sun. The team performed a detailed analysis to remove these effects from the TESS data.

When a planet crosses in front of its star from our perspective, an event called a transit, its passage causes a distinct dip in the star's brightness. TESS monitors large swaths of the sky, called sectors, for 27 days at a time. During this long stare, the mission's cameras regularly capture snapshots that allow scientists to track changes in stellar brightness.

Regular dips in a star's brightness signal the possibility of a transiting planet. Usually, it takes at least two observed transits to recognize a planet's presence.

"As luck would have it, the second of three TESS transits occurred when the spacecraft was near its closest point to Earth. At such times, TESS is not observing because it is busy downlinking all of the stored data," said co-author Diana Dragomir, a research assistant professor at the University of New Mexico in Albuquerque. "To fill the gap, our team was granted observing time on Spitzer, which caught two additional transits in 2019 and enabled us to confirm the orbital period of AU Mic b."

Spitzer was a multipurpose infrared observatory operating from 2003 until its decommissioning on Jan. 30, 2020. The mission proved especially adept at detecting and studying exoplanets around cool stars. Spitzer returned the AU Mic observations during its final year.

Because the amount of light blocked by a transit depends on the planet's size and orbital distance, the TESS and Spitzer transits provide a direct measure of AU Mic b's size. Analysis of these measurements show that the planet is about 8% larger than Neptune.

Observations from instruments on ground-based telescopes provide upper limits for the planet's mass. As a planet orbits, its gravity tugs on its host star, which moves slightly in response. Sensitive instruments on large telescopes can detect the star's radial velocity, its motion to-and-fro along our line of sight. Combining observations from the W. M. Keck Observatory and NASA's InfraRed Telescope Facility in Hawaii and the European Southern Observatory in Chile, the team concluded that AU Mic b has a mass smaller than 58 Earths.

This discovery shows the power of TESS to provide new insights into well-studied stars like AU Mic, where more planets may be waiting to be found.

"There is an additional candidate transit event seen in the TESS data, and TESS will hopefully revisit AU Mic later this year in its extended mission," Plavchan said. "We are continuing to monitor the star with precise radial velocity measurements, so stay tuned."

For decades, AU Mic has intrigued astronomers as a possible home for planets thanks to its proximity, youth and bright debris disk. Now that TESS and Spitzer have found one there, the story comes full circle. AU Mic is a touchstone system, a nearby laboratory for understanding the formation and evolution of stars and planets that will be studied for decades to come.

TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA's Goddard Space Flight Center. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA's Ames Research Center in California's Silicon Valley; the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts; MIT's Lincoln Laboratory; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes and observatories worldwide are participants in the mission.

NASA's Jet Propulsion Laboratory (JPL) in Southern California managed the Spitzer mission for the agency's Science Mission Directorate in Washington. Spitzer science data continue to be analyzed by the science community via the Spitzer data archive located at the Infrared Science Archive housed at IPAC at Caltech in Pasadena. Science operations were conducted at the Spitzer Science Center at Caltech. Spacecraft operations were based at Lockheed Martin Space in Littleton, Colorado. Caltech manages JPL for NASA.

En español: http://ciencia.nasa.gov/las-misiones-tess-y-spitzer-de-la-nasa-descubren-un-planeta-orbitando-una-joven-e-inusual-estrella

"Squeezing" is used in physics, among other things, to improve the resolution of measuring instruments. It allows disturbing noise to be suppressed in a way that smaller signals can be detected more sensitively.

The research team led by physicist Professor Eva Weig at the University of Konstanz has now been able to show how such a squeezed state can be measured in a much simpler way than with the existing methods. Moreover, the new method allows examining squeezed states in systems where such measurements were not possible before.

The results are published in the current issue of the journal Physical Review X.

An international research team led by Dr. Tali Ilovitsh of the Biomedical Engineering Department at Tel Aviv University developed a noninvasive technology platform for gene delivery into breast cancer cells. The technique combines ultrasound with tumor-targeted microbubbles. Once the ultrasound is activated, the microbubbles explode like smart and targeted warheads, creating holes in cancer cells' membranes, enabling gene delivery. Conducted over two years, the research was published on June 9 in the journal Proceedings of the National Academy of Sciences (PNAS).

Dr. Ilovitsh developed this breakthrough technology during her post-doctorate research at the lab of Prof. Katherine Ferrara at Stanford University. The technique utilizes low frequency ultrasound (250 kHz) to detonate microscopic tumor-targeted bubbles. In vivo, cell destruction reached 80% of tumor cells.

"Microbubbles are microscopic bubbles filled with gas, with a diameter as small as one tenth of a blood vessel," Dr. Ilovitsh explains. "At certain frequencies and pressures, sound waves cause the microbubbles to act like balloons: they expand and contract periodically. This process increases the transfer of substances from the blood vessels into the surrounding tissue. We discovered that using lower frequencies than those applied previously, microbubbles can significantly expand, until they explode violently. We realized that this discovery could be used as a platform for cancer treatment and started to inject microbubbles into tumors directly."

Dr. Ilovitsh and the rest of the team used tumor-targeted microbubbles that were attached to tumor cells' membranes at the moment of the explosion, and injected them directly into tumors in a mouse model. "About 80% of tumor cells were destroyed in the explosion, which was positive on its own," says Dr. Ilovitsh. "The targeted treatment, which is safe and cost-effective, was able to destroy most of the tumor. However, it is not enough. In order to prevent the remaining cancer cells to spread, we needed to destroy all of the tumor cells. That is why we injected an immunotherapy gene alongside the microbubbles, which acts as a Trojan horse, and signaled the immune system to attack the cancer cell."

On its own, the gene cannot enter into the cancer cells. However, this gene aimed to enhance the immune system was co-injected together with the microbubbles. Membrane pores were formed in the remaining 20% of the cancer cells that survived the initial explosion, allowing the entry of the gene into the cells. This triggered an immune response that destroyed the cancer cell.

"The majority of cancer cells were destroyed by the explosion, and the remaining cells consumed the immunotherapy gene through the holes that were created in their membranes," Dr. Ilovitsh explains. "The gene caused the cells to produce a substance that triggered the immune system to attack the cancer cell. In fact, our mice had tumors on both sides of their bodies. Despite the fact that we conducted the treatment only on one side, the immune system attacked the distant side as well."

Dr. Ilovitsh says that in the future she intends to attempt using this technology as a noninvasive treatment for brain-related diseases such as brain tumors and other neurodegenerative conditions such as Alzheimer's and Parkinson's diseases. "The blood-brain barrier does not allow for medications to penetrate through, but microbubbles can temporary open the barrier, enabling the arrival of the treatment to the target area without the need for an invasive surgical intervention."

COLUMBUS, Ohio - The rapid politicization of the COVID-19 pandemic can be seen in messages members of the U.S. Congress sent about the issue on the social media site Twitter, a new analysis found.

Using artificial intelligence and resources from the Ohio Supercomputer Center, researchers conducted an analysis that covered all 30,887 tweets that members sent about COVID-19 from the first one on Jan. 17 through March 31.

The algorithm they created could correctly classify the political party of the member who sent each tweet 76 percent of the time, based only on the text of the tweet and the date it was sent.

"We found that once the parties started to figure out the political implications of the issue, polarization was evident in the tweets pretty quickly," said Jon Green, co-author of the study and doctoral student in political science at The Ohio State University.

The study was published today (June 24, 2020) in the journal Science Advances.

"It is remarkable that we could identify partisanship even when members have only 280 characters to send their messages in Twitter," said study co-author Skyler Cranmer, the Carter Phillips and Sue Henry Professor of Political Science at Ohio State.

Democrats sent out significantly more tweets (19,803) about COVID-19 than did Republicans (11,084), the study showed.

The gap in the number of tweets sent by Democratic versus Republican politicians widened after the first case of community spread was identified in California and grew further following the declaration of a national emergency.

"This suggests Democratic members were sending earlier and stronger signals to their constituents that they should be concerned about the crisis," Cranmer said.

What Democrats and Republicans tweeted about concerning the pandemic was different, too, results showed.

For example, the word "health" was used in 26 percent of Democratic tweets, but only 15 percent of Republican tweets.

Overall, Democrats were more likely to discuss public health and safety, as well as American workers, while Republicans emphasized a general need for national unity, discussed China and business, and framed the pandemic as a war.

As one component of the analysis, the researchers identified members who fell in the range of what they called "partisan overlap." Congressional members in this overlap area were those whose tweets were more likely to be confused by the algorithm with those of someone from the other party.

Only 31 percent of members fell in this area.

"That means for 69 percent of members, their tweets are more partisan than the most similar member of the other party," Green said.

Polarization was not constant over time.

In the first full week after the first mention of COVID-19, the algorithm developed by the researchers had relatively low accuracy when trying to determine whether a Democrat or a Republican wrote a particular tweet. That indicates there was little polarization.

However, polarization quickly rose, peaking during the week beginning Feb. 9. It then declined slightly in early-to-mid March before rising again in late March as the parties debated economic relief packages.

The findings suggest that Congress missed an opportunity early in the pandemic to develop a consensus that could have helped the United States respond to the crisis, Cranmer said.

"Something on the scale of COVID-19 requires a large-scale government response. The government can respond much better when it is united in its mission," he said.

Virtually screening antiviral compounds to model their interactions with the SARS-CoV-2 virus may enable scientists to more easily identify antiviral drugs that work against the virus while informing the search for viable vaccine candidates, according to a new study. By screening for interactions with certain structural domains and active sites on the virus, this structure-based approach may help scientists identify existing drugs that can be repurposed, including therapies developed to treat MERS-CoV, SARS-CoV, Ebola, and HIV. This approach may also assist with the development of new drugs and protein-based SARS-CoV-2 vaccines with fewer experiments and higher reliability than traditional methods. Information about SARS-CoV-2 reported from its recent genome sequencing has revealed key targets for drugs and vaccines, including the spike protein complex, which helps mediate viral entry into host cells, as well as the main protease, an enzyme that enables viral replication and transcription. To test how these elements of the virus' structure may be used to search virtually for prospective drugs, Pritam Kumar Panda and colleagues computationally screened 640 antiviral compounds from a database against the spike protein and main protease using AutoDock Vina, an open-source program for identifying the "best fit" orientation of a molecule that binds to a protein. The researchers then used two additional programs, UCSF Chimera and Discovery Studio Visualizer, to analyze these molecular orientations. The researchers found that an antiviral polymerase inhibitor PC786 targets several SARS-CoV-2 receptors with high affinity, making it a standout among the antiviral drugs they studied. Panda et al. also identified several additional antiviral drugs with strong binding affinities to the spike protein and main protease, revealing a number of drugs that may be candidates for further research in efforts to fight SARS-CoV-2.

An analysis of COVID-19-related tweets issued by members of Congress from January 17 through March 31, 2020 finds that Democrats and Republicans quickly polarized along party lines in their messaging about the virus on Twitter. The findings underscore the lack of political consensus as the crisis ballooned in the United States - a consensus that democratic countries rely on during emergencies. Democrats emphasized COVID-19 earlier, with the disparity between total Democratic and Republican tweets becoming pronounced after the CDC identified community spread in California on February 26, widening after the United States declared a national emergency on March 13, and later declining as the severity of the pandemic became undeniable. Democrats also tended to discuss the crisis more frequently, issuing a total of 19,803 tweets about COVID-19 during this time period while Republican Congress members issued 11,084 (a ratio of about 71 tweets per Democrat to 45 tweets per Republican). The parties also favored different word choices, resulting in messaging with different points of emphasis - Democrats most frequently used words such as "health," "leave," and "testing," while Republicans most frequently using words such as "together," "United States," "China," and "businesses." Jon Green and colleagues note that political elites in the United States have not always exhibited such polarization in times of crisis, with Republican and Democratic lawmakers issuing joint statements after the terrorist attacks on September 11, 2001. To investigate polarization in congressional tweets during the COVID-19 crisis, Green et al. collected a list of Twitter handles (including multiple active accounts, both official and personal, for some Congress members) and merged them with data on members' partisanship and ideology. The researchers flagged tweets related to COVID-19, which they identified using a set of dictionaries consisting of terms used to identify a particular topic (for example, "COVID-19" could be identified as "covid," "coronavirus," or "the virus"). Next, they trained a random forest machine learning model to recognize partisanship using 70% of the tweets, then applied this model to predict party affiliations of the authors of the remaining 30% based on the content and timing of the tweets. The model correctly classified the partisanship of 76% of tweets based solely on the language used and the dates on which they were sent.

Related Video from Science's Digital Media Department: https://youtu.be/jNa7PaLNVVU This video should be used in its entirety, not modified. Please credit to Science/AAAS.

A new study led by researchers at the USC Leonard Davis School of Gerontology is the first to demonstrate that a tiny protein has a big impact on health and longevity in both animals and humans.

The researchers examined humanin, a peptide encoded in the small genome of mitochondria -- the powerhouses of the cell. From experiments in laboratory animals to measurements in human patients, the multi-site collaboration demonstrates how higher levels of humanin in the body are connected to longer lifespans and better health. It is linked to a lower risk for diseases such as Alzheimer's.

"Humanin has long been known to help prevent many age-related diseases, and this is the first time that it has been shown that it can also increase lifespan," said senior author Pinchas Cohen, professor of gerontology, medicine and biological sciences and dean of the USC Leonard Davis School.

An intriguing evolutionary history

Humanin has been found not only in human mitochondria but also throughout the animal kingdom, a sign that its related gene has been maintained, or conserved, throughout evolution. The study, which was published online in the journal Aging on June 23, examined humanin in several animal species, including worms and mice, as well as humans, including Alzheimer's patients and children of centenarians.

The results highlight the potential for humanin and other mitochondrial proteins to become treatments for age-related ailments. They also indicate that humanin may be an ancient mitochondrial signaling mechanism that is key for regulating the body's health and lifespan, said first author and USC Leonard Davis Research Assistant Professor Kelvin Yen.

More humanin, longer lifespans

Humanin levels have previously been observed to decrease with age in many species. In this new study, the scientists observed higher levels of humanin in organisms predisposed to long lives, including the famously age-resistant naked mole rat, which experiences only a very slow decline in levels of humanin circulating in the body throughout its 30-year lifespan.

In contrast, mice experience a 40% drop in humanin over the first 18 months of life, and primates such as rhesus macaques appeared to have a similarly dramatic drop in humanin between the ages of 19 and 25.

In humans, researchers observed this phenomenon of higher and more sustained levels of humanin in 18 children of centenarians, versus a control group of 19 children of non-centenarians. Individuals whose parents reach 100 years old are statistically more likely than other people to reach very old age.

In some species, including worms and mice, modifying their genes to produce higher amounts of humanin within their bodies was enough to significantly increase lifespans. But these longer-lived animals had fewer offspring. Scientists have observed a similar pattern in long-lived humans.

"This tradeoff between longevity and reproduction is thought to be due to an evolutionarily conserved balance between using energy to produce more offspring or using the energy to maintain the organism for future reproductive efforts," Yen said. "Evolutionarily speaking, the goal of life is to reproduce and then you're done, but if you can't reproduce, you should try to hang around as long as possible, and a side effect of that is longevity."

Indication of - and protection against - disease

Higher humanin levels aren't just linked to increased lifespan; lower levels may increase the risk of disease and lower resistance to toxic exposures.

The researchers analyzed samples of cerebral spinal fluid from a small number of Alzheimer's patients and control individuals without dementia and noticed that humanin levels were much lower in the Alzheimer's patients. And in newborn cord blood samples, high levels of humanin correlated with a high mitochondrial DNA (mtDNA) copy number, or the number of copies of the mitochondrial genome present within each cell.

"Humanin levels are inversely correlated with a decrease in mitochondrial DNA (mtDNA) copy number, which in itself has been associated with a number of different diseases such as cancer, kidney disease, and cardiovascular disease," Yen said.

Potential for treatments

Cohen's laboratory was one of three groups that independently discovered humanin and has continued to unlock the secrets of the mitochondrial genome. Other promising mitochondrial peptides characterized by Cohen's team include MOTS-c, which plays a role in communication between the mitochondria and the nucleus in cells and appears to mimic the effects of exercise.

This new wide-ranging study highlights the importance of humanin as a potentially powerful regulator of lifespan and health, and harnessing it for treatments could address a variety of age-related illnesses, Cohen said.

"This study, as well as many others, suggest that humanin administration would be an effective therapeutic treatment for a large number of diseases and further solidifies the importance of the mitochondria beyond its traditional role as the 'powerhouse of the cell,'" he said.

Astronomers this month released the largest collection of sharp, detailed images of debris disks around young stars, showcasing the great variety of shapes and sizes of stellar systems during their prime planet-forming years. Surprisingly, nearly all showed evidence of planets.

The images were obtained over a period of four years by a precision instrument, the Gemini Planet Imager (GPI), mounted on the 8-meter Gemini South telescope in Chile. The GPI uses a state-of-the-art adaptive optics system to remove atmospheric blur, providing the sharpest images to date of many of these disks.

Ground-based instruments like GPI, which is being upgraded to conduct similar observations in the northern sky from the Gemini North Telescope in Hawaii, can be a way to screen stars with suspected debris disks to determine which are worth targeting by more powerful, but expensive, telescopes to find planets -- in particular, habitable planets. Several 20-, 30- and 40-meter telescopes, such as the Giant Magellan Telescope and the Extremely Large Telescope, will come online in the next couple of decades, while the orbiting James Webb Space Telescope is expected to be launched in 2021.

"It is often easier to detect the dust-filled disk than the planets, so you detect the dust first and then you know to point your James Webb Space Telescope or your Nancy Grace Roman Space Telescope at those systems, cutting down the number of stars you have to sift through to find these planets in the first place," said Tom Esposito, a postdoctoral fellow at the University of California, Berkeley.

Esposito is first author of a paper describing the results that appeared June 15 in The Astronomical Journal.

Comet belts around other stars

The debris disks in the images are the equivalent of the Kuiper Belt in our solar system, a frigid realm about 40 times farther from the sun than Earth -- beyond the orbit of Neptune -- and full of rocks, dust and ice that never became part of any planet in our solar system. Comets from the belt -- balls of ice and rock -- periodically sweep through the inner solar system, occasionally wreaking havoc on Earth, but also delivering life-related materials like water, carbon and oxygen.

Of the 26 images of debris disks obtained by the Gemini Planet Imager (GPI), 25 had "holes" around the central star that likely were created by planets sweeping up rocks and dust. Seven of the 26 were previously unknown; earlier images of the other 19 were not as sharp as those from GPI and often didn't have the resolution to detect an inner hole. The survey doubles the number of debris disks imaged at such high resolution.

"One of the things we found is that these so-called disks are really rings with inner clearings," said Esposito, who is also a researcher at the SETI Institute in Mountain View, California. "GPI had a clear view of the inner regions close to the star, whereas in the past, observations by the Hubble Space Telescope and older instruments from the ground couldn't see close enough to the star to see the hole around it."

The GPI incorporates a coronagraph that blocks the light from the star, allowing it to see as close as one astronomical unit (AU) from the star, or the distance of the Earth from our sun: 93 million miles.

The GPI targeted 104 stars that were unusually bright in infrared light, indicating they were surrounded by debris reflecting the light of the star or warmed by the star. The instrument recorded polarized near-infrared light scattered by small dust particles, about a thousandth of a millimeter (1 micron) in size, likely the result of collisions among larger rocks in a debris disk.

"There has been no systematic survey of young debris disks nearly this large, looking with the same instrument, using the same observing modes and methods," Esposito said. "We detected these 26 debris disks with very consistent data quality, where we can really compare the observations, something that is unique in terms of debris disk surveys."

The seven debris disks never before imaged in this manner were among 13 disks around stars moving together though the Milky Way, members of a group called the Scorpius-Centaurus stellar association, which is located between 100 and 140 parsecs from Earth, or some 400 light years.

"It is like the perfect fishing spot; our success rate was much greater than anything else we have ever done," said Paul Kalas, a UC Berkeley adjunct professor of astronomy who is second author of the paper. Because all seven are around stars that were born in the same region at roughly the same time, "that group itself is a mini-laboratory where we can compare and contrast the architectures of many planetary nurseries developing simultaneously under a range of conditions, something that we really didn't have before," Esposito added.

Of the 104 stars observed, 75 had no disk of a size or density that GPI could detect, though they may well be surrounded by debris left over from planet formation. Three other stars were observed to host disks belonging to the earlier "protoplanetary" phase of evolution.

What did our solar system look like in its infancy?

The extent of the debris disks varied widely, but most ranged between 20 and 100 AU. These were around stars that ranged in age from tens of millions of years to a few hundred million years, a very dynamic period for the evolution of planets. Most were larger and brighter than the sun.

The one star, HD 156623, that did not have a hole in the center of the debris disk was one of the youngest in the group, which fits with theories of how planets form. Initially, the protoplanetary disk should be relatively uniform, but as the system ages, planets form and sweep out the inner part of the disk.

"When we look at younger circumstellar disks, like protoplanetary disks that are in an earlier phase of evolution, when planets are forming, or before planets have started to form, there is a lot of gas and dust in the areas where we find these holes in the older debris disks," Esposito said. "Something has removed that material over time, and one of the ways you can do that is with planets."

Because polarized light from debris disks can theoretically tell astronomers the composition of the dust, Esposito is hoping to refine models to predict the composition -- in particular, to detect water, which is thought to be a condition for life.

Studies like these could help answer a lingering question about our own solar system, Kalas said.

"If you dial back the clock for our own solar system by 4.5 billion years, which one of these disks were we? Were we a narrow ring, or were we a fuzzy blob?" he said. "It would be great to know what we looked like back then to understand our own origins. That is the great unanswered question."

The researchers, in this perspective, discuss about the recent outbreak of COVID-19 throughout the world and its relation with food safety and biosecurity. This new type of pneumonia of unknown causes in the Hubei Province of China has hit public health and economy extremely hard. COVID-19 has already crossed other forms of flu and viral infections in morbidity and mortality. More than 100,000 confirmed cases had been reported, by March 6, 2020, with a mortality rate of around 3.5%. So far, more than 90 countries have reported confirmed cases of the COVID-19.

Initial epidemiological studies trace to the Huanan seafood market in China where almost half of the infected were found to be exposed to the market. Most patients had visited or come in close contact with the affected individuals from Wuhan. From previous experience with outbreaks of viral infections similar to COVID-19 (MERS-CoV, SARS-CoV) it is known that transmission through food is unlikely. Precautions are, nevertheless, necessary to avoid exposure to agents that can be the source of harboring the viral agents. Bats, for example, are recognized as natural reservoir hosts of Coronavirus. To date, over 200 novel coronaviruses have been identified in bats. And, for a fact, they are favorite indigenous protein culinary in many countries in Asia, Africa, and islands of Oceania. Also, hunting for consumption as bushmeat and medicine is common in these countries.

With the lack of clear knowledge about the source and spread of Coronavirus, it should be feasible to take precautionary measures regarding contact with potential hosts like bats. There must be check and strict measures on legal trade of likely carriers of Coronavirus and the illegal trade of bushmeat and other sources.

Eelgrass, a species of seagrass named for its long slippery texture, is one of nature's superheroes. It offers shade and camouflage for young fish, helps anchor shorelines, and provides food and habitat for many marine species.

A University of Washington study adds one more superpower to the list of eelgrass abilities: warding off the toxin-producing algae that regularly close beaches to shellfish harvests. Researchers found evidence that there are significantly fewer of the single-celled algae that produce harmful toxins in an area more than 45 feet, or 15 meters, around an eelgrass bed.

"We're not in the laboratory. The effect we're seeing is happening in nature, and it's an effect that's really widespread within this group of harmful algae. What we see is this halo of reduced abundance around the eelgrass beds," said Emily Jacobs-Palmer, a research scientist at the UW. She is the lead author of the study published this spring in the open-access journal PeerJ.

Researchers sampled five coastal sites three times in the spring and summer of 2017. Four sites were within Puget Sound and one was in Willapa Bay, on Washington's outer coast.

In addition to a traditional visual ecological survey at each site, the researchers used a type of genetic forensics to detect species that might not be easily seen or present at the time of the survey.

Scientists put on waders and walked parallel to shore in water less than knee deep while scooping up seawater samples to analyze the environmental DNA, or eDNA, present. This method collects fragments of genetic material to identify organisms living in the seawater.

The researchers sampled water from each site at the same point in the tidal cycle both inside the eelgrass bed and at regular intervals up to 45 feet away from the edge. For comparison they also surveyed a location farther away over bare seabed.

"In the DNA fragments we saw everything from shellfish to marine worms, osprey, bugs that fell in the water," Jacobs-Palmer said. "It's quite fascinating to just get this potpourri of organisms and then look for patterns, rather than deciding on a pattern that we think should be there and then looking for that."

The researchers analyzed the eDNA results to find trends among 13 major groups of organisms. They discovered that dinoflagellates, a broad class of single-celled organism, were scarcer in and around the eelgrass beds than in surrounding waters with bare seabed.

"We were asking how the biological community changes inside eelgrass beds, and this result was so strong that it jumped out at us, even though we weren't looking for it specifically," said senior author Ryan Kelly, a UW associate professor of marine and environmental affairs.

The result has practical applications, since certain species of dinoflagellate populations can spike and produce toxins that accumulate in shellfish, making the shellfish dangerous or even deadly to eat.

The phrase "harmful algal bloom" has a formal definition that was not measured for this study. But authors say the trend appeared when the overall dinoflagellate populations were high.

"I have heard people talk about a trade-off between shellfish and eelgrass, in terms of land use in Puget Sound. Now, from our perspective, there's not a clean trade-off between those things -- these systems might be able to complement one another," Kelly said.

To explore the reasons for the result, the authors looked at differences in water chemistry or current motion around the bed. But neither could explain why dinoflagellate populations were lower around the eelgrass.

Instead, the authors hypothesize that the same biological reasons why dinoflagellates don't flourish inside eelgrass beds -- likely bacteria that occur with eelgrass and are harmful to dinoflagellates -- may extend past the bed's edge.

"It was known that there is some antagonistic relationship between eelgrass and algae, but it's really important that this effect seems to span beyond the bounds of the bed itself," Jacobs-Palmer said.

The discovery of a "halo effect" by which eelgrass discourages the growth of potentially harmful algae could have applications in shellfish harvesting, ecological restoration or shoreline planning.

"These beds are often really large, and that means that their perimeter is also really large," Jacobs-Palmer said. "That's a lot of land where eelgrass is potentially having an effect."

In follow-up work, researchers chose two of the sites, in Port Gamble on the Kitsap Peninsula and Skokomish on Hood Canal, to conduct weekly sampling from late June through October 2019. They hope to verify the pattern they discovered and learn more about the environmental conditions that might allow the halo to exist.

Out beyond our solar system, visible only as the smallest dot in space with even the most powerful telescopes, other worlds exist. Many of these worlds, astronomers have discovered, may be much larger than Earth and completely covered in water — basically ocean planets with no protruding land masses. What kind of life could develop on such a world? Could a habitat like this even support life?

A team of researchers led by Arizona State University (ASU) recently set out to investigate those questions. And since they couldn’t travel to distant exoplanets to take samples, they decided to recreate the conditions of those water worlds in the laboratory. In this case, that laboratory was the Advanced Photon Source (APS), a U.S. Department of Energy (DOE) Office of Science User Facility at the DOE’s Argonne National Laboratory.

“People hardly think about astrophysics when talking about an X-ray facility. But we can use a facility like the APS to understand an object too distant for us to see.” — Dan Shim, associate professor, Arizona State University

What they found — recently published in Proceedings of the National Academy of Sciences — was a new transitional phase between silica and water, indicating that the boundary between water and rock on these exoplanets is not as solid as it is here on Earth. This pivotal discovery could change the way astronomers and astrophysicists have been modeling these exoplanets, and inform the way we think about life evolving on them.

Dan Shim, associate professor at ASU, led this new research. Shim leads ASU’s Lab for Earth and Planetary Materials and has long been fascinated by the geological and ecological makeup of these distant worlds. That composition, he said, is nothing like any planet in our solar system — these planets may have more than 50% water or ice atop their rock layers, and those rock layers would have to exist at very high temperatures and under crushing pressure.

“Determining the geology of exoplanets is tough, since we can’t use telescopes or send rovers to their surfaces,” Shim said. “So we try to simulate the geology in the lab.”

How does one do that? First, you need the right tools. For this experiment, Shim and his team brought their samples to two APS beamlines: GeoSoilEnviroCARS (GSECARS) at beamline 13-ID-D, operated by the University of Chicago, and High-Pressure Collaborative Access Team (HPCAT) at beamline 16-ID-B, operated by Argonne’s X-ray Science Division.

The samples were compressed in diamond anvil cells, essentially two gem quality diamonds with tiny flat tips. Place a sample between them and you can squeeze the diamonds together, increasing the pressure.

“We can raise the pressure up to multiple millions of atmospheres,” said Yue Meng, a physicist in Argonne’s X-ray Science Division and a co-author on the paper. Meng was one of the main designers of the techniques used at HPCAT, which specializes in high-pressure, high-temperature experiments.

“The APS is one of the few places in the world where you can conduct this kind of cutting-edge research,” she said. “The beamline scientists, technicians and engineers make this research possible.”

The pressure of exoplanets, Shim said, can be calculated, even though the data we have on these planets is limited. Astronomers can measure the mass and density, and if the size and the mass of the planet are known, the right pressure can be determined.

Once the sample is pressurized, infrared lasers — which can be adjusted to smaller than the width of a human blood cell — are used to heat it up. “We can bring the sample up to thousands of degrees Fahrenheit,” said Vitali Prakapenka, a beamline scientist at GSECARS, a research professor at the University of Chicago and a co-author on the paper. “We have two high power lasers that shine on the sample from both sides precisely aligned with an ultra-bright APS X-ray probe and temperature measurements along the optical paths with a sub-micron accuracy.”

The temperature of exoplanets is harder to measure, because there are so many factors that determine it: the amount of heat contained inside the planet, the age of the planet, and the amount of radioactive isotopes decaying inside the structure, giving off more heat. Shim’s team calculated a range of temperatures to work from.

Once the sample is pressurized and heated up, the APS’ ultra-bright X-ray beams (which can see through the diamonds and into the sample itself) can allow scientists to take snapshots of atomic scale structure changes during the chemical reactions as they happen. In this case, Shim and his team immersed a small amount of silica in water, increased the pressure and temperature, and monitored how the materials would react.

What they discovered is that at high temperature and pressure of about 30 gigapascals (about 300,000 times the standard atmospheric pressure on Earth), the water and rock start to merge.

“If you were to build a planet with water and rock, you would assume that the water forms a layer above rock,” he said. “What we found is that is not necessarily true. With enough heat and pressure, the boundary between rock and water becomes fuzzy.”

This is a new idea that will need to be incorporated into models of exoplanets, Prakapenka said.

“The main point is that it tells the people modeling the structure of these planets that the composition is more complicated than we thought,” Prakapenka said. “Before we believed that there was a separation between rock and water, but based on these studies, there is no sharp boundary.”

Scientists have conducted similar experiments before, Shim said, but those were predicated on an Earth-like setting with smaller increments of water. Observing this new phase transition gives modelers a better idea about the actual geological makeup of water-rich exoplanets, and also insights into what kinds of life might call those exoplanets home.

“It’s a starting point to build the way chemistry works on these planets,” Shim said. “How water interacts with rock is important for life on Earth, and therefore, it is also important to understanding the type of life that might be on some of these worlds.”

Shim acknowledges that this research is not the first thing one might picture when thinking about a light source like the APS. But it’s exactly that diversity that he said is an advantage of large-scale user facilities.

“People hardly think about astrophysics when talking about an X-ray facility,” he said. “But we can use a facility like the APS to understand an object too distant for us to see.”

Background: The characterization of COVID-19 in patients with cancer remains limited in published studies and nationwide surveillance analyses. Reports from China and Italy have raised the possibility that patients with cancer on active therapy have a higher risk of COVID-19 related severe events, although there is a knowledge gap as to which aspects of cancer and its treatment increase the risk of severe COVID-19 disease.

A team of researchers at Memorial Sloan Kettering Cancer Center (MSK) reported on the epidemiology of COVID-19 illness experienced at an NCI-designated cancer center during the height of pandemic in New York City.

Bottom Line: According to a new study from Memorial Sloan Kettering published June 24 in Nature Medicine, patients in active cancer treatment who develop COVID-19 infection don't fare any worse than other hospitalized patients. Notably, metastatic disease, recent chemotherapy, or major surgery within the previous 30 days did not show a significant association with either hospitalization or severe respiratory illness due to COVID-19. Researchers say their findings suggest that no one should delay cancer treatment because of concerns about the virus.

Author Comments: "If you're an oncologist and you're trying to figure out whether to give patients chemotherapy, or if you're a patient who needs treatment, these findings should be very reassuring," says Ying Taur, MD, PhD, an Infectious Disease Specialist at MSK.

"The course and clinical spectrum of this disease is still not fully understood and this is just one of many studies that will need to be done on the connections between cancer and COVID-19," explained Mini Kamboj, MD, Chief Medical Epidemiologist, Infection Control at MSK. "But the big message now is clear: People shouldn't stop or postpone cancer treatment."

Method and Findings: The study looked at 423 MSK patients diagnosed with COVID-19 between March 10 and April 7. Overall, 40 percent were hospitalized for COVID-19, and 20 percent developed severe respiratory illness. About 9 percent had to be placed on a mechanical ventilator, and 12 percent died. The most frequent cancer types included solid tumors such as breast, colorectal, and lung cancer. Lymphoma was the most common hematologic malignancy. Over half of the cases were metastatic solid tumors.

Similar to other studies in the general population, the researchers found that age, race, cardiac disease, hypertension, and chronic kidney disease correlated with severe outcomes. The investigators found that patients taking immunotherapy drugs called immune checkpoint inhibitors were more likely to develop severe disease and require hospitalization. Further research is required to look at the effects of these drugs. But other cancer treatments, including chemotherapy and surgery, did not contribute to worse outcomes.

Although most beer consumers can distinguish between different bitter tastes in beer, this does not appear to influence which beer they like. It seems they just like beer, regardless of the source of the bitterness.

That is the conclusion of Penn State sensory researchers who conducted multiple studies with more than 150 self-identified beer drinkers to see if they could differentiate bitterants in beer. But the question of whether humans can discriminate between types of bitterness remains controversial, according to researcher John Hayes, associate professor of food science.

"Given that countless craft breweries around the country have been very successful in selling a near-endless variety of India pale ales -- better known as IPAs -- we wanted to move past testing bitter chemicals in water to see if consumers could differentiate different bitters in a real food such as beer," he said.

To determine beer drinkers' ability to distinguish between bitter chemicals, study participants in blind taste tests were given commercially available nonalcoholic beer spiked with hop extract Isolone, quinine -- the ingredient that makes tonic water bitter -- and sucrose octaacetate, a food additive so bitter it has been used as a nail-biting and thumb-sucking deterrent.

Participants, about half men and half women, most in their 30s, took part in three experiments. In the first, researchers asked subjects to rate the amount of bitterness and other beer flavor attributes in samples using an intensity scale, to ensure the beer samples were equally bitter.

In the next experiment, beer consumers rated how samples differed from a reference on a seven-point scale. Then, to understand how each sample differed from others, participants checked attributes on a list of 13 descriptors to describe the samples.

In the final experiment, beer consumers tasted the beer samples, rated how much they liked each sample and provided a forced-choice ranking for best-liked to worst-liked.

According to Hayes, who is director of Penn State's Sensory Evaluation Center in the College of Agricultural Sciences, most participants were able to discern differences in bitterness -- even though the samples had been matched for bitterness intensity.

"But our results also show that, despite being able to differentiate between the different bitter chemicals, they were not able to verbally describe these differences, even when provided a list of attributes," he said. "Further, we found no consistent effect on liking or preference. The source of bitterness did not influence which beers they liked."

In the sampled beers, researchers attempted to match the flavor profile of a pale ale style beer, in which high bitterness is not only accepted but desired by consumers, noted lead researcher Molly Higgins, who will receive her doctoral degree in food science this August. Higgins explained that she recruited regular beer consumers because they are more likely to be aware of the various flavor profiles of beer and respond positively to the bitter qualities of samples during testing.

"What we found was unsurprising in hindsight -- beer consumers simply like beer," she said. "So, it seems that for consumers who drink IPAs, a beer just needs to have a bitter profile. For them, it's about bitterness in general, not the specific bitter quality -- if it's there, they will like it."

Higgins suggests that this finding may help in quality assurance at breweries. "Beer consumers may be more forgiving than previously believed when it comes to small variations across batches," she said.

Higgins noted that some breweries use highly trained expert tasters to evaluate each batch. If these experts detect any off notes or flaws in the final product, they may throw out an entire batch. "When breweries can establish an acceptable range for sensory attributes for their final products, they can make better decisions about how much variation is tolerable," she said.

However, there are many segments of beer consumers, Higgins added, and within the craft beer market there is a unique subgroup of consumers who are devoted to their IPAs. Those beer drinkers, she explained, doubtlessly pick up on more of the finer bitter notes created by novel blends of hops. Those consumers patronize craft breweries and are willing to try many different beers.

The bitter beer tasting study, recently published in Nutrients, was part of a larger research project conducted by Higgins at Penn State for her dissertation. Because of its sensory complexity and wide acceptance by many consumers, she contends, beer is a good model food to explore the capacity of people to perceive bitter taste.

Higgins said when people ask her why she would do this kind of a study, she points out that it's not about beer.

"The overall goal of my dissertation research was to learn more about bitterness and bitterness perception, and to better understand how individuals learn to like bitter products," she said. "We hope that understanding bitterness can guide further research that helps people incorporate healthy bitter foods into their diet. The overall goal is to look at more complex bitter foods, such as kale and broccoli, and figure out ways to increase their consumption and liking."

People with inoperable anal cancer treated with carboplatin-paclitaxel had fewer complications and lived longer than those who received another chemotherapy that has been more often administered.

The results from an international trial, published by the Journal of Clinical Oncology, suggest that carboplatin-paclitaxel become the standard of care for anal cancer, a rare disease that accounts for less than 3% of all gastrointestinal malignancies. The InterAAct trial compared carboplatin-paclitaxel with cisplatin plus 5-flourouracil (5FU).

"The InterAAct trial identifies carboplatin-paclitaxel as the optimal chemotherapy regimen in the first-line setting for inoperable anal cancer," said lead U.S. investigator Cathy Eng, MD, David H. Johnson Chair in Surgical and Medical Oncology at Vanderbilt University and co-leader of the Gastrointestinal Cancer Research Program at Vanderbilt-Ingram Cancer Center. "Carboplatin-paclitaxel was associated with less toxicity and a trend toward improved survival, which suggests that it should become the standard of care for these patients and the backbone for future phase three trials."

The overall survival of patients enrolled on the carboplatin-paclitaxel arm of the clinical trial was 20 months compared to 12.3 months for those on the cisplatin-5FU arm. Carboplatin-paclitaxel was associated with significantly less adverse effects (36%) compared to cisplatin-5FU (62%).

The study enrolled 91 patients from the United States, Australia, Germany, Norway and the United Kingdom between December 2013 and November 2017. The International Rare Cancers Initiative formed the Anal Cancer Working Group to design and conduct trials with the goal of providing metastatic anal cancer patients with new treatment strategies.

Patients with inoperable anal cancer have a five-year survival rate of approximately 30%.

Paclitaxel was first documented as a treatment for advanced anal cancer in 2011 and was later combined with carboplatin. Response rates of 69% had led some clinicians to administer it as a first-line treatment, but the cisplatin-5FU regimen had been adopted internationally.

UC Davis MIND Institute researchers found an unexpected set of mental illnesses in patients with a spectrum of a rare genetic disorder. Their study revealed the need for clinicians to consider the complexities of co-existing conditions in patients with both psychological and fragile X associated disorders.

Double-hit fragile X spectrum cases

The patients had a "double-hit" condition that combined features and symptoms of fragile X syndrome and premutation disorder.

Fragile X syndrome (FXS), a rare single-gene disorder, is the leading inherited cause of intellectual disability. It is caused by a lack of the fragile X mental retardation protein (FMRP) resulting from a change, called mutation, in the FMR1 gene.

In most people, the CGG section of the FMR1 gene is repeated between 10 to 40 times. In some rare cases, individuals have premutation disorder when their FMR1 gene has 55 to 200 CGG repeats. When this section expands to over 200 repeats, there is a full mutation in the gene. This full mutation causes an inability to produce FMRP and leads to FXS.

The study presented 14 cases of male patients with FMR1-gene mutations and a variety of psychiatric disorders. These patients, ages ranging between nine and 58 years, had features resembling FXS and symptoms common among premutation carriers.

FXS symptoms include hand flapping, hyperactivity, recurrent ear infections, severe anxiety and tantrums. Individuals with FXS frequently have speech and language delays, behavior challenges and symptoms of autism spectrum disorder (ASD).

Premutation, on the other hand, is associated with the development of neurological problems associated with aging. One example of such age-related problems is Fragile X-associated tremor ataxia syndrome (FXTAS). FXTAS is a disease characterized by progressively severe tremor and difficulty with walking and balance. Premutation is also associated with medical and psychiatric problems such as migraines, hypertension, sleep apnea, restless legs syndrome, anxiety and depression.

Neurological and developmental problems

The study found that patients with premutation had a much earlier onset of neurological problems. Some even had earlier symptoms of neurodegeneration, particularly if they had developmental delay or ASD during their childhood. They also showed trouble with their emotional processing.

"Lower levels of FMRP can cause a range of emotional processing issues," said Andrea Schneider, associate research scientist in the Department of Pediatrics and at UC Davis MIND Institute and the lead author on the study. "Some of the common emotion-related disorders we found are mood disorders, anxiety and psychotic features."

The researchers called for more studies on the association of psychosis and lower FMRP levels - especially in patients with a double hit condition. The case series also highlighted the need for clinicians to consider additional possible diagnosis for FMR1 mutations in psychiatric patients.

"Clinicians need to be aware of the physical and mental toll on patients with a FMR1 mutation who also show symptoms of psychosis or early onset of neurological problems," said Paul Hagerman, professor of biochemistry and molecular medicine at UC Davis and co-author on the study. "This understanding helps develop treatment plans that address the multiple needs of these patients."