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A new analysis of thousands of native and nonnative Michigan bees shows that the most diverse bee communities have the lowest levels of three common viral pathogens.

University of Michigan researchers netted and trapped more than 4,000 bees from 60 species. The bees were collected at winter squash farms across Michigan, where both managed honeybee colonies and wild native bees pollinate the squash flowers.

All but one species--Apis mellifera, the common European honeybee--are native bees. The number of bee species found at each farm ranged from seven to 49.

Consistently, lower virus levels were strongly linked to greater species richness among the local bee communities. The study was published online Feb. 11 in the journal Ecology.

"This result is exciting because it suggests that promoting diverse bee communities may be a win-win strategy to simultaneously reduce viral infections in managed honeybee colonies while helping to maintain native bee biodiversity," said study lead author Michelle Fearon, a postdoctoral researcher in the University of Michigan Department of Ecology and Evolutionary Biology.

"In light of recent global pollinator population declines that are due in part to the spread of pathogens, these results offer hope that conservation efforts could also broadly benefit pollinator health," said Fearon, who conducted the study for her doctoral dissertation. She is now pursuing a follow-up study that explores how natural areas keep pollinator communities healthy.

The Ecology study is the first to show that high levels of biodiversity within bee communities can help dilute the harmful effects of viral pathogens. Support for this "dilution effect" has been reported in other host­--pathogen systems--such as tick-borne Lyme disease--but this is the first time it's been seen with pollinator viruses. The idea of a dilution effect remains controversial among ecologists, however.

Fearon and her colleagues collected 4,349 bees at 14 Michigan winter squash farms over two summers. Michigan winter squashes include acorn squash, butternut squash, spaghetti squash and pumpkins.

Honeybees were found at all of the sites, and a diverse array of native bees were also present in the squash fields and along field edges. In fact, native pollinators were much more common visitors to the squash flowers than honeybees at most locations.

Four types of bees--the European honeybee, the eastern bumblebee (Bombus impatiens), the squash bee (Eucera pruinosa) and several species of sweat bee (genus Lasioglossum)--were the most consistently abundant species among the bee communities that were sampled.

Those four groups were tested for the presence of three viruses that commonly infect managed honeybee colonies: deformed wing virus, black queen cell virus and sacbrood virus.

These pathogens contribute to high rates of colony loss among honeybees, and there are no widely available treatments that beekeepers can use to control them. Previous studies suggested that native bees are less commonly infected and may be less likely to transmit the pathogens to other bees.

The viruses spread as bees move from flower to flower, gathering pollen and nectar and pollinating the plants in the process. Consumption of virus-contaminated pollen is believed to be a primary mode of transmission.

For each of the four target bee groups in the U-M study, researchers found that lower viral prevalence was strongly linked to greater biodiversity of the local bee community: the more bee species present, the lower the percentage of bees infected.

Species-rich communities included many native bee species, which apparently helped to dilute the impact of the pathogens.

"Native bees likely reduce the viral prevalence in pollinator communities because they are poorer viral hosts than honeybees. This means that some native bees don't get as sick as honeybees and are less likely to spread the virus to other bees," said study co-author Elizabeth Tibbetts, a professor in the U-M Department of Ecology and Evolutionary Biology who was Fearon's dissertation adviser.

"So, bees from pollinator communities with lots of species are less likely to get sick because they are sharing flowers with many bee species that are less likely to spread the virus, while bees from communities dominated by honeybees are more likely to share flowers with honeybees that are good at spreading the virus," Tibbetts said.

Bees are indispensable pollinators, supporting both agricultural productivity and the diversity of flowering plants worldwide. In recent decades, both native bees and managed honeybee colonies have seen population declines blamed on multiple interacting factors including habitat loss, parasites and disease, and pesticide use.

"We found encouraging evidence that pollinator conservation efforts can broadly benefit the health of both managed honeybee colonies and native bees," Fearon said. "This management strategy could be especially crucial in agricultural areas where crop flowers are visited by both honeybees and native bees--places that may be hot spots for viral transmission among bee species."

How much does a power system's reliability depend on the temperature? Electric power system generator resource adequacy modeling is designed to help determine capacity requirements for electric power system operators across the United States. While calculating resource adequacy requirements has been done for a century, it requires ongoing attention as the generation mix is constantly expanding and changing. A new paper contributes to these ongoing reliability considerations by using a unique data set to determine how both low and high temperatures reduce the reliability of coal, gas, diesel, hydroelectric, and nuclear power generators and thus affect the amount of generation markets should contract for.

The paper, "Resource Adequacy Implications of Temperature-dependent Electric Generator Availability," by researchers at Carnegie Mellon University, was published in Applied Energy.

"Our focus is on better understanding the determinants of generator availability and incorporating these considerations into resource adequacy modeling," says Jay Apt, a Professor and Co-Director of the Carnegie Mellon Electricity Industry Center, who co-authored the paper. "Ultimately, this could improve a system operator's ability to determine how much generation is needed when the temperature is very cold or very hot."

The researchers evaluated the PJM Interconnection, the largest electric transmission system operator by installed generation capacity and load in North America, by making use of observed temperature-dependent forced outage rates over 25 years. Current grid resource adequacy modeling assumes that generator failures are unrelated to temperature, though this presents substantial resource adequacy risk. For example, in PJM's case, extreme weather events such as the Polar Vortex cold snap of 2014 added significant stress to the electric grid, suggesting that contrary to prevailing assumptions, generator failures are correlated. Further, assuming unconditional independence can lead to underestimating power system capacity requirements.

The researchers first determined that extreme temperatures, both hot and cold, resulted in less output from PJM's fleet. They then computed capacity requirements for PJM in two different scenarios for a 12-month period in 2018 and 2019. The first represented current practices wherein unconditional independence is assumed, and the second allowed for generator availability to depend on temperature. Additionally, they explored how accelerating changes to the resource mix (i.e.; moving from fossil fuels to solar and wind energy) and future temperature increases under climate change may affect resource adequacy at PJM.

Given the strong seasonality of extreme temperatures, the researchers considered whether monthly procurement targets would help PJM reduce capacity requirements as opposed to the current annual procurement model. They observed the accumulated loss of load expectation (LOLE) - the probability of a blackout due to insufficient power generation - during each calendar month under an annual procurement approach, using both unconditional and temperature-dependent forced outage rates. After accounting for temperature dependence of generator availability, they determined that monthly capacity procurement targets would substantially reduce annual average reserve procurement in PJM with negligible effect on LOLE. This, they explained, is because spring and fall months experience mild temperatures, leading to both lower loads and increased generator availability.

Ultimately, this analysis demonstrates the importance of considering temperature-dependent conditions in resource adequacy modeling. The sort of monthly or seasonal capacity procurement the authors propose could reduce PJM's reserve margin from the 26.6% reserve margin PJM procured in 2018-19 to 22.9%, representing a $315 million annual economic benefit. The authors note that further research is needed to account for the risk of lost load from generator outages during sustained extreme weather events, incorporate demand response resources, quantify operational flexibility needs, and allow system operators to better understand the value of procuring operating reserves.

Astronomers found something they weren't expecting at the heart of the globular cluster NGC 6397: a concentration of smaller black holes lurking there instead of one massive black hole.

Globular clusters are extremely dense stellar systems, which host stars that are closely packed together. These systems are also typically very old -- the globular cluster at the focus of this study, NGC 6397, is almost as old as the universe itself. This cluster resides 7,800 light-years away, making it one of the closest globular clusters to Earth. Due to its very dense nucleus, it is known as a core-collapsed cluster.

At first, astronomers thought the globular cluster hosted an intermediate-mass black hole. These are the long-sought "missing link" between supermassive black holes (many millions of times our Sun's mass) that lie at the cores of galaxies, and stellar-mass black holes (a few times our Sun's mass) that form following the collapse of a single massive star. Their mere existence is hotly debated. Only a few candidates have been identified to date.

"We found very strong evidence for an invisible mass in the dense core of the globular cluster, but we were surprised to find that this extra mass is not 'point-like' (that would be expected for a solitary massive black hole) but extended to a few percent of the size of the cluster," said Eduardo Vitral of the Paris Institute of Astrophysics (IAP) in Paris, France.

To detect the elusive hidden mass, Vitral and Gary Mamon, also of IAP, used the velocities of stars in the cluster to determine the distribution of its total mass, that is the mass in the visible stars, as well as in faint stars and black holes. The more mass at some location, the faster the stars travel around it.

The researchers used previous estimates of the stars' tiny proper motions (their apparent motions on the sky), which allow for determining their true velocities within the cluster. These precise measurements for stars in the cluster's core could only be made with Hubble over several years of observation. The Hubble data were added to well-calibrated proper motion measurements provided by the European Space Agency's Gaia space observatory which are less precise than Hubble's observations in the core.

"Our analysis indicated that the orbits of the stars are close to random throughout the globular cluster, rather than systematically circular or very elongated," explained Mamon. These moderate-elongation orbital shapes constrain what the inner mass must be.

The researchers conclude that the invisible component can only be made of the remnants of massive stars (white dwarfs, neutron stars, and black holes) given its mass, extent, and location. These stellar corpses progressively sank to the cluster's center after gravitational interactions with nearby less massive stars. This game of stellar pinball is called "dynamical friction," where, through an exchange of momentum, heavier stars are segregated in the cluster's core and lower-mass stars migrate to the cluster's periphery.

"We used the theory of stellar evolution to conclude that most of the extra mass we found was in the form of black holes," said Mamon. Two other recent studies had also proposed that stellar remnants, in particular, stellar-mass black holes, could populate the inner regions of globular clusters. "Ours is the first study to provide both the mass and the extent of what appears to be a collection of mostly black holes in the center of a core-collapsed globular cluster," added Vitral.

The astronomers also note that this discovery raises the possibility that mergers of these tightly packed black holes in globular clusters may be an important source of gravitational waves, ripples through spacetime. Such phenomena could be detected by the Laser Interferometer Gravitational-Wave Observatory experiment, which is funded by the National Science Foundation and operated by Caltech in Pasadena, California and MIT in Cambridge, Massachusetts.

EL PASO, Texas - Science is a step closer to a new response to obesity, thanks in part to a study conducted by a team that included Sergio Iñiguez, Ph.D., associate professor of psychology at The University of Texas at El Paso.

The 10-member team led by Brandon Warren, Ph.D., assistant professor of pharmacodynamics at the University of Florida, made discoveries about a specific area of the brain tied to recollection and the desire to seek and consume food. It could lead to a way to inhibit the desire to overeat.

Iñiguez, who directs UTEP's Iñiguez Behavioral Neuroscience Lab and helped design novel experimental techniques for the research, said that people tend to overeat when exposed to cues or environments that remind them of treats, which is one reason why people opt for dessert even after a filling meal. The study showed that neurons in a specific part of the brain control the link between the cue (seeing the dessert) and the action (ordering the dessert). Iñiguez and team found that animal subjects consumed fewer treats when they regulated that region of the animal's brain.

The techniques and the data eventually could help overcome some issues linked to obesity such as stroke, Type 2 diabetes, high blood pressure, high levels of bad cholesterol, and coronary heart disease.

"This is a big discovery because we now have experimental tools that allow us to turn off neurons while the subjects engage in a specific behavior," Iñiguez said. "This research shows that a specific part of the prefrontal cortex of the brain is important for the initial stages of learning to seek food."

BUFFALO, N.Y. - Humpback and bowhead whales are the only mammals other than humans thought to progressively change the songs they sing through a process of cultural learning.

But maybe the humpbacks are no longer part of that trio. Humpbacks might be singing songs that are not as "cultured" as once assumed.

A new study by a University at Buffalo researcher is directly contradicting the widely accepted cultural transmission hypothesis suggesting that whales learn their songs from other whales.

"It seems like that is not correct," says Eduardo Mercado, a professor of psychology in UB's College of Arts and Sciences. "Our findings indicate that neither cultural transmission nor social learning contributes significantly to how humpback whales change their songs over time.

"I think the results are provocative and will probably make other whale researchers livid or dismissive, but at least the discussion won't be boring!"

The study, published Tuesday (Feb. 9) in the Journal of Comparative Psychology, analyzed songs from groups of humpbacks that were not in acoustic contact with each other, yet still produced acoustically comparable songs.

"The idea that humpback whales are a distinguished part of the animal kingdom because of their ability to culturally learn songs is apparently not true," says Mercado. "But to me, what the whales are doing is actually more impressive.

"Cultural transmission implies that what's heard is copied. That means it doesn't matter what is heard or what is copied. But what we found is very specific and precise, without a trace of arbitrary vocalization. The songs change over time in a fashion that's even more precise than what humans do when language develops."

The talented club DJ serves as an appropriate metaphor for changing whale song.

"DJs can't just randomly go from one song to the next," says Mercado. "They have to think about beat matching, tempo and mood in order to maintain a continuous flow.

"I think that might be true of the whales. When they make changes, they do so in relation to what preceded it. They're basically beat matching when they change songs - and we found similarities in populations that had no social contact or genetic links."

Mercado says existing research claims that humpback populations isolated from one another do not change their songs in the same way. Each population is original, taking their songs in original directions.

"These things are not true," says Mercado. "I compare songs over 40 years and compare populations that have never been in contact with one another, and they're doing basically the same thing."

Despite large and sometimes rapid changes, whales often end up singing similar songs, according to Mercado. The cultural transmission hypothesis is attractive in part because it's hard to imagine what mechanism might instigate the song variation.

But previous research has relied heavily on subjectively defined categories. Songs sounding like a human snore would be placed in a "snore" category. Any subsequent analysis would depend on how well the categories captured the intricacies of the song.

"I didn't categorize things at all and used purely acoustic measurements," says Mercado, who specifically chose published records of data to avoid any suggestion of cherry picking the data. "This paper is based on direct measurements of sound features without any categorization or subjective labeling."

Mercado says the results of the current study question the role of vocal imitation and cultural transmission in humpback whale song, but they do not resolve why the songs are changing.

"These results tell me that whales are sophisticated in ways that researchers and observers hadn't previously considered," says Mercado. "What we're hearing is a level of acoustic sophistication which is beyond the ability of humans.

"That's something that deserves both appreciation and further study. I'd like to examine why whale song changes and explore the benefit of that change."

Researchers of the Research Programme on Biomedical Informatics (GRIB) from UPF and Hospital del Mar Medical Research Institute (IMIM) in Barcelona, Spain, have identified behavioural and linguistic changes in tweets in Spanish published by users suffering from depression and who are taking medication to treat this disease.

Their work has been published in Journal of Medical Internet Research and was led by Ferran Sanz; with Angela Leis and Francesco Ronzano as first authors, who conducted the work together with Miguel Angel Mayer and Laura I Furlong, all from the Integrative Biomedical Informatics research group.

Depression is one of the most widespread mental illnesses. According to the World Health Organization, it affects more than 322 million people of all ages and is one of the leading causes of disability worldwide.

The possibility of analysing massive data shared on social networks provides us with new opportunities to better understand the behaviour of their users. In this study, using Big Data and text mining, the scientists analysed tweets by users who mentioned they were taking drugs for the treatment of depressive disorders. The main goal was to detect the effects of this medication through changes in the language used in their tweets or in the way these people used Twitter.

In a previous study, the team of researchers observed that users of Twitter who potentially suffer from depression display specific behavioural and linguistic features. This article focuses on the changes in the features of the messages that may be associated with treatment with antidepressant drugs.

The most notable results revealed that during periods in which users stated they were receiving antidepressant drug treatment their Twitter activity increased with longer messages but posting fewer messages at night. They also interacted more with other users (for example, through an increase in number of mentions per tweet, which may reflect an interest in interacting with other people) and also an increase in positive emotions, related to happiness and surprise. "We can state that the behavioural patterns of people who are in treatment with antidepressant drugs change and tend to resemble those of people who do not suffer from depression", Angela Leis details.

There are various types of antidepressant drugs, and this study focuses specifically on selective serotonin reuptake inhibitors, which are the most commonly prescribed drug for treating depression. First, they selected timelines of users mentioning SSRI antidepressants in their tweets. Then, "we analysed changes in behavioural and linguistic features in the tweets posted while users were in treatment, in comparison with tweets posted by the same users when it was less likely that they were taking these drugs", Francesco Ronzano explains. 186 users and their timelines with 668,842 tweets were finally included in the study.

"The use of techniques based on Big Data and text mining, which enable detecting changes in the way in which users interact in their social networks, such as Twitter, can provide us with new opportunities to follow up and monitor patients suffering from one of the most widespread, disabling health problems as is depression", concludes Ferran Sanz, full professor with the UPF Department of Experimental and Health Sciences (DCEXS) and director of the Research Programme on Biomedical Informatics (GRIB) of the IMIM and UPF.

In your quest for true love and that elusive happily ever after, are you waiting for the "right" person to come along, or do you find yourself going for the cutest guy or girl in the room, hoping things will work out? Do you leave your options open, hoping to "trade-up" at the next opportunity, or do you invest in your relationship with an eye on the cost-benefits analysis?

For something so fundamental to our existence, mate selection remains one of humanity's most enduring mysteries. It's been the topic of intense psychological research for decades, spawning myriad hypotheses of why we choose whom we choose.

"Mate choice is really complicated, especially in humans," said Dan Conroy-Beam(link is external), an assistant professor in the Department of Psychological and Brain Sciences at UC Santa Barbara, and author of a paper(link is external) in the journal Personality and Social Psychology Review. "And there have been a lot of people who have proposed abstract ideas about how it might happen."

One line of thinking, for instance, posits that we assess potential mates against an internal threshold of preferred qualities and attributes -- a "minimum bar," that they have to meet to be considered a potential partner.

"And we learn where that minimum bar is based on how other people treat us," he said. Another model describes the dating market somewhat like the European social dances of the 18th century.

"One side approaches the other side and they get these kinds of temporary relationships going," Conroy-Beam said. "And basically you stay in a relationship until you get a better offer and everybody kind of recurrently ditches their partners for better ones."

But these mate selection models, and others like them, don't capture a lot of the nuance that goes into real-life mate selection, Conroy-Beam noted.

"When you have a system that is particularly complicated like human mating markets are, verbal models are sometimes not such a great way to understand what's going on," he said. Competing desires and social dynamics play heavily into mate selection, he explained, adding layers of complexity and moving parts that can't be captured or quantified.

So what can hold human-like multiple levels of detail and complexity? The next best thing: a computer simulation. In an effort to move understanding of mate choice forward, Conroy-Beam has developed a new approach -- called "couple simulation" -- that essentially test-drives models of mate selection against the attributes and priorities of a sample of real-life couples.

"The real advantage that we have here is that we're going away from just these verbal models and into explicit computational models," he said. "We're directly simulating people's real choices; we're removing the limits of doing this in our own heads because we have computers that can keep track of all the very complicated interactions that are going on."

Sim Dating

The process begins by measuring the traits and preferences of a population of a few hundred couples -- real people who have made real-life mate choices. That data is crunched into simulated copies of each person -- "avatar agents" that have the same attributes and desires as their human counterparts, except in the simulated world they're single.

"We break them up and throw all these little agents into the market," said Conroy-Beam, who received support for his research from the National Science Foundation's Early CAREER program. "Then we run various algorithms and see which ones do the best job at putting them back together with the agent representing their real-world partner."

The algorithms represent different models of mate selection, which dictate the rules by which the agents can interact, based on the predictions of the model. In addition to the Aspiration Threshold Model (minimum bar) and the Gale-Shapley Algorithm (optimizing stable pairs), the team also used the Kalick-Hamilton Model (KHM), which assumes people choose mates according to their attractiveness, and a new model Conroy-Beam proposed called the Resource Allocation Model (RAM).

"It's thinking about mate choice in terms of investment of limited resources," he said. "So you've only got so much time and so much money and so much energy that you can dedicate to potential partners. And so your question as the person who's looking for a partner is 'who deserves most of these limited resources?'"

Conroy-Beam's model, it turns out, proved to be the most accurate, correctly matching approximately 45% of the couples in the simulated market in the very first runs of couple simulation. What makes the Resource Allocation Model work so well?

"There are a number of differences between RAM and the other models," he said. "The other models treat attraction like an on/off switch, but RAM allows for gradients of attraction. It also incorporates reciprocity: the more a potential mate pursues you, the more you pursue them in return," he said. The Gale-Shapley algorithm came in second, followed by the aspirational threshold model and then the KHM (attractiveness). Random pairings came in last.

It's still early days for couple simulation; after all, Conroy-Beam said, 45% right is still 55% wrong. For a first pass, however, 45% accuracy is impressive, and according to the study, the people in this cohort also report having higher-quality relationships (more satisfied, more committed, more love, less jealous) than the people in the inaccurately paired couples.

Conroy-Beam and his team at the Computational Mate Choice Lab at UCSB will continue to refine their models, which he calls "really rough sketches," to increase accuracy. They're hoping to soon conduct a longer term longitudinal study to see if couples that are accurately predicted differ in longevity.

"We hope to do this across cultures as well as to incorporate same-sex couples in the near future," he said. "We also have plans in the next couple of years to try to apply this to single people to prospectively predict their future relationships."

CHICAGO (February 12, 2021): Since 2010, National Institutes of Health (NIH) funding to support surgeon scientists has, remarkably, risen significantly while funding to support other non-surgeon physicians has significantly decreased. This growth has occurred despite an overall decrease in NIH funding and an increase in demand for clinical productivity. These findings are according to an "article in press" published on the website of the Journal of the American College of Surgeons ahead of print.

"Our findings challenge the notion that overall funding to support surgeon scientists has decreased; instead, it has dramatically increased," said Martha A. Zeiger, MD, FACS, Director of the Surgical Oncology Program, National Cancer Institute, NIH.

"When we looked at funding to support surgeons alone, we were surprised to find that funding has increased by 40 percent in terms of both numbers of surgeons being supported and the amount of funding. So, it's quite a remarkable and surprising finding."

About the study

Using an NIH portfolio database, study researchers were able to conduct a thorough analysis of funding to support all surgeons, including all surgical specialties and subspecialties in the U.S. Other studies have only captured funding patterns of entire surgical departments, certain institutions, or individual surgical specialties.

For this study, Dr. Zeiger and colleagues searched NIH databases for 2010 and 2020 to identify all active and awarded NIH grants to support surgeon scientists by surgical specialty, total costs, and whether the grant supported basic science, clinical outcomes, or clinical trials research.

The researchers also compared total funding to support surgeon scientists with funding granted to support non-physician scientists with PhDs and funding granted to support other non-surgeon physicians.

The analysis showed increases in both the number of surgeons and the amount of funding for each surgical specialty. The percentage of NIH-funded surgeons (compared with the total number of surgeons) increased by 40 percent. In contrast, the percentage of other NIH-funded physicians dropped by 27 percent.

Key findings

In June 2010, 715 surgeon scientists were supported by 1,113 grants, totaling $614 million in NIH funding. In June of 2020, 1,031 surgeon scientists were supported by 1,453 grants, totaling $872 million in NIH funding.
General surgery-based subspecialties topped the list, comprising one-quarter of the funded specialties and close to 40 percent of the total funding.
Obstetrics/gynecology was the second most funded surgical specialty.
Neurological surgery was third.

Surgical oncology funding remains strong

General surgeons with a sub-subspecialty in surgical oncology led the group of general surgery-trained surgeons in number of NIH-funded surgeons and total grant awards in both 2010 and 2020.

In 2020, 27 percent of those trained in general surgery were surgical oncologists, holding about 44 percent of the total grant cost for all general surgeons.
In 2010, surgical oncology also represented the majority of general surgery subspecialties, holding more than one-third of the funding for surgeons trained in general surgery.

Focus on basic science stable

"We also found that basic science has remained stable since 2010," Dr. Zeiger said. In fact, 70 percent of principal investigator-initiated grants are in basic science, and surgeons have maintained that percentage over the past 10 years."

From 2010 to 2020, the researchers also found an increase in cooperative research grants, underscoring the fact that surgeon scientists working in multidisciplinary team research is on the rise.

"Surgeons contribute a tremendous amount to science, and, historically, they always have. They are very challenged these days because obtaining NIH funding has become more competitive," Dr. Zeiger said. "We also have increasing administrative responsibilities because of the electronic medical record, and clinical productivity is emphasized more and more across the country, especially for surgical subspecialties."

"Overall, I think it's remarkable that surgeon scientists have not only maintained, but significantly increased the amount of NIH funding they are supported by over the past 10 years. Most important, they have also maintained a strong emphasis on basic science research," she concluded.

"Surgeon scientists have made outstanding gains in securing more NIH research funding. These exciting results show the dedication that they have to life-long learning and innovative research, along with a passion for science. Moreover, these findings show how committed surgeons are to seeking scientific pathways to continually improve the quality of surgical care for our patients, which is our highest priority," said ACS Executive Director David B. Hoyt, MD, FACS, a study coauthor.

Scientists at Lund University have discovered how E. coli bacteria target and degrade the well-known oncogene MYC, which is involved in many forms of cancer. The study is now published in Nature Biotechnology.

Cancer cells grow too fast, outcompete normal cells and spread to distant sites, where they cause metastases. Understanding what makes cancer cells so efficient and threatening is critically important and stopping them has always been the goal of cancer research. Early studies identified so-called ''oncogenes''; genes that that normally control cell growth but when mutated may be responsible for the creation of cancer cells and explain their competitive advantage.

The pleiotropic transcription factor MYC has been named ''the quintessential oncogene'' and is hyperactive in the majority of human cancers. Targeting MYC is therefore highly desirable. Still, finding c-MYC inhibitors for therapeutic use has been problematic and MYC itself has long been viewed as "undruggable".

Researchers at Lund University have made the surprising discovery that uropathogenic E. coli deplete c-MYC protein from infected cells and tissues as a result of accelerated c-MYC protein degradation and attenuated MYC expression.

The discovery was made after observing that children with acute pyelonephritis have decreased MYC expression. By screening molecules released by the bacteria, Lon protease was identified as the main effector of MYC degradation, with selectivity for MYC. The bacterial strategy was then translated into cancer therapy, showing prominent effects of Lon treatment in two different cancer models. Potent treatment effects on tumor growth and increased survival support the therapeutic potential of this molecule.. Surprisingly, the Lon protease was shown to mainly affect cells where MYC is overactive, suggesting limited toxicity. These findings have now been published in Nature Biotechnology

''The next step is to understand this "magical molecule" in more detail and to develop the project for future clinical trials''

HANOVER, N.H. - February 12, 2021 - A newly discovered planetary system will provide researchers with the rare chance to study a group of growing planets, according to research co-led by Dartmouth.

The new system, named TOI 451, is made up of at least three neighboring planets that orbit the same sun. The planets range in size between that of Earth and Neptune.

According to the research team, NASA's Hubble Space Telescope and its planned successor, the James Webb Space Telescope, can be used to study the atmosphere of each planet. Such research could lead to information on how planetary systems like our own solar system evolve.

"The sun in this planetary system is very similar to our own sun, but much younger," said Elisabeth Newton, an assistant professor of physics and astronomy at Dartmouth who co-leads the research team. "By studying these planets in the context of others, we can piece together the picture of how planets form and develop."

The discovery of TOI 451, published in the Astronomical Journal, began in 2019 through the review of data from NASA's Transiting Exoplanet Survey Satellite (TESS).

All three planets were found using data from TESS. Once the discoveries were made, follow-up work was done using NASA's Spitzer Space Telescope, the ground-based Southern African Large Telescope and other resources. Overall, more than 50 researchers representing dozens of institutions contributed to the research.

"The dataset from TESS is really unmatched for discovering these kinds of young planets," said Andrew Mann, an assistant professor at the University of North Carolina at Chapel Hill and research co-lead. "We are fortunate to be working in a time where we have access to data from such a successful exoplanet mission."

The planets complete full orbits around their sun on timescales ranging from about two days to 16 days. The host star is similar in mass to Earth's sun, but much younger at only 120 million years old.

"The sun of the newly discovered planets is like a teenager compared to our own sun. That means its planets are still changing and evolving," said Newton.

The star and its planets are part of the Pisces-Eridanus stellar stream, an association of young stars that stretches across much of the southern galactic hemisphere. The association of stars and its age were previously identified by separate teams using data from TESS and the European Space Agency's Gaia spacecraft.

According to NASA, there are over 4,000 known planets outside of the solar system. Most of these planets are older and much farther away from Earth than the new system.

While most discoveries are single planets, other multi-planet systems have been found in the past. Only seven other young systems with multiple transiting planets have been discovered, according to the research team.

The finding of multiple planets in the same system allows researchers to compare the development of the individual bodies, knowing that they formed and evolved around the same sun.

In addition to the planets, researchers have also found evidence of a disk of debris that is "dustier" but otherwise similar in ways to the solar system's own asteroid belt.
In 2019, the research group discovered DS Tuc Ab, an exoplanet orbiting one of the brightest young stars known.

A more aggressive approach to treating acne that marries the disciplines of psychology and dermatology is needed, according to two UC Riverside psychology researchers.

They also assert that women and people with darker skin disproportionately suffer from acne's psychological impacts.

"Acne is pervasive, physically harmless, and painless, so we all-too-often underestimate its impacts as the quintessential nuisance of adolescence and puberty," said UCR psychology professor Misaki Natsuaki, who authored the paper along with Tuppett Yates, also a UCR psychology professor.

The insinuation, including by developmental scientists, can be that hurtful monikers such as "pizza face" and "crater face" are best shrugged off.

But psychological effects of acne among adolescents are often "toxic," the researchers say. In advocating for a reconsideration of treatment, they allude to the prevalence of acne among adolescents - 20% suffer from moderate to severe acne, and 85% experience recurrent bouts.

"Acne can leave psychological scars, especially during adolescence when physical appearance becomes more salient for self-esteem, and internalizing psychopathology such as depression gains prominence," Natsuaki said.

Numerous studies show direct links between acne and depression, anxiety, and suicidal thoughts. Teens with acne have more difficulty forming friendships, finding romantic partners, and feeling connected to school.
When shown a photograph of a teenager with facial acne, 65% of adolescents said skin was the first thing they notice. In a photo of a clear-skinned teen, youth said they noticed the skin first only 14% of the time. Young people attribute to adolescents who suffer acne traits such as "nerdy," "stressed," and "lonely."

And research has shown females experience negative psychological impacts at a rate higher than males.

"Aesthetic ideals of clear and unblemished skin are held by both sexes," the researchers wrote in their recent paper, "Adolescent Acne and Disparities in Mental Health," published by the journal Child Development Perspectives. "But females experience greater social pressure to attain these ideals than males."

Adolescents with darker skin color, many of whom come from ethnic-racial minority backgrounds in the United States, are likely to suffer disproportionate effects of acne because of heightened incidence of post-acne scarring and hyperpigmentation.

The authors argue that structural systems of inequality, which fuel health care disparities in the United States, further exacerbate acne and related psychosocial distress among individuals receiving public health insurance, who are more likely to belong to one or more ethnic-racial minority groups. The complex infrastructure of the health insurance system, uneven geographical density of health care providers, and reluctance to provide dermatology appointments to children with public insurance all contribute these disparities, the researchers wrote. In one study, only 29% of dermatology clinics schedule appointments with children on public insurance, whereas 96% of children with private insurance received appointments.

"According to dermatology research, the psychological burden of acne is on par with that of other serious illnesses, such as diabetes," Yates said. "Acne is a medical condition with clear psychological effects - effects that are non-randomly distributed as a function of gender, skin color, and socioeconomic status."

"So effective acne treatment rests at the intersection of medicine, psychology, and sociology."

The recently published study is a follow-up to a study Natsuaki published this past year. In that study, Natsuaki suggested that an effective-but-tightly-regulated acne medication, isotretinoin, should be revisited. Isotretinoin was associated with a higher incidence of adolescent suicide - a link some say was unwarranted - and Natsuaki asserted the benefits of the drug outweigh its risks.

Using observations from NASA's Transiting Exoplanet Survey Satellite (TESS), an international team of astronomers has discovered a trio of hot worlds larger than Earth orbiting a much younger version of our Sun called TOI 451. The system resides in the recently discovered Pisces-Eridanus stream, a collection of stars less than 3% the age of our solar system that stretches across one-third of the sky.

The planets were discovered in TESS images taken between October and December 2018. Follow-up studies of TOI 451 and its planets included observations made in 2019 and 2020 using NASA's Spitzer Space Telescope, which has since been retired, as well as many ground-based facilities. Archival infrared data from NASA's Near-Earth Object Wide-Field Infrared Survey Explorer (NEOWISE) satellite - collected between 2009 and 2011 under its previous moniker, WISE - suggests the system retains a cool disk of dust and rocky debris. Other observations show that TOI 451 likely has two distant stellar companions circling each other far beyond the planets.

"This system checks a lot of boxes for astronomers," said Elisabeth Newton, an assistant professor of physics and astronomy at Dartmouth College in Hanover, New Hampshire, who led the research. "It's only 120 million years old and just 400 light-years away, allowing detailed observations of this young planetary system. And because there are three planets between two and four times Earth's size, they make especially promising targets for testing theories about how planetary atmospheres evolve."

A paper reporting the findings was published on Jan. 14 in The Astronomical Journal and is available online.

Stellar streams form when the gravity of our Milky Way galaxy tears apart star clusters or dwarf galaxies. The individual stars move out along the cluster's original orbit, forming an elongated group that gradually disperses.

In 2019, a team led by Stefan Meingast at the University of Vienna used data from the European Space Agency's Gaia mission to discover the Pisces-Eridanus stream, named for the constellations containing the greatest concentrations of stars. Stretching across 14 constellations, the stream is about 1,300 light-years long. However, the age initially determined for the stream was much older than we now think.

Later in 2019, researchers led by Jason Curtis at Columbia University in New York City analyzed TESS data for dozens of stream members. Younger stars spin faster than their older counterparts do, and they also tend to have prominent starspots - darker, cooler regions like sunspots. As these spots rotate in and out of our view, they can produce slight variations in a star's brightness that TESS can measure.

The TESS measurements revealed overwhelming evidence of starspots and rapid rotation among the stream's stars. Based on this result, Curtis and his colleagues found that the stream was only 120 million years old - similar to the famous Pleiades cluster and eight times younger than previous estimates. The mass, youth, and proximity of the Pisces-Eridanus stream make it an exciting fundamental laboratory for studying star and planet formation and evolution.

"Thanks to TESS's nearly all-sky coverage, measurements that could support a search for planets orbiting members of this stream were already available to us when the stream was identified," said Jessie Christiansen, a co-author of the paper and the deputy science lead at the NASA Exoplanet Archive, a facility for researching worlds beyond our solar system managed by Caltech in Pasadena, California. "TESS data will continue to allow us to push the limits of what we know about exoplanets and their systems for years to come."

The young star TOI 451, better known to astronomers as CD-38 1467, lies about 400 light-years away in the constellation Eridanus. It has 95% of our Sun's mass, but it is 12% smaller, slightly cooler, and emits 35% less energy. TOI 451 rotates every 5.1 days, which is more than five times faster than the Sun.

TESS spots new worlds by looking for transits, the slight, regular dimmings that occur when a planet passes in front of its star from our perspective. Transits from all three planets are evident in the TESS data. Newton's team obtained measurements from Spitzer that supported the TESS findings and helped to rule out possible alternative explanations. Additional follow-up observations came from Las Cumbres Observatory - a global telescope network headquartered in Goleta, California - and the Perth Exoplanet Survey Telescope in Australia.

Even TOI 451's most distant planet orbits three times closer than Mercury ever approaches to the Sun, so all of these worlds are quite hot and inhospitable to life as we know it. Temperature estimates range from about 2,200 degrees Fahrenheit (1,200 degrees Celsius) for the innermost planet to about 840 F (450 C) for the outermost one.

TOI 451 b orbits every 1.9 days, is about 1.9 times Earth's size, and its estimated mass ranges from two to 12 times Earth's. The next planet out, TOI 451 c, completes an orbit every 9.2 days, is about three times larger than Earth, and holds between three and 16 times Earth's mass. The farthest and largest world, TOI 451 d, circles the star every 16 days, is four times the size of our planet, and weighs between four and 19 Earth masses.

Astronomers expect planets as big as these to retain much of their atmospheres despite the intense heat from their nearby star. Different theories of how atmospheres evolve by the time a planetary system reaches TOI 451's age predict a wide range of properties. Observing starlight passing through the atmospheres of these planets provides an opportunity to study this phase of development and could aid in constraining current models.

"By measuring starlight penetrating a planet's atmosphere at different wavelengths, we can infer its chemical composition and the presence of clouds or high-altitude hazes," said Elisa Quintana, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "TOI 451's planets offer excellent targets for such studies with Hubble and the upcoming James Webb Space Telescope."

Observations from WISE show that the system is unusually bright in infrared light, which is invisible to human eyes, at wavelengths of 12 and 24 micrometers. This suggests the presence of a debris disk, where rocky asteroid-like bodies collide and grind themselves to dust. While Newton and her team cannot determine the extent of the disk, they envision it as a diffuse ring of rock and dust centered about as far from the star as Jupiter is from our Sun.

The researchers also investigated a faint neighboring star that appears about two pixels away from TOI 451 in TESS images. Based on Gaia data, Newton's team determined this star to be a gravitationally bound companion located so far from TOI 451 that its light takes 27 days to get there. In fact, the researchers think the companion is likely a binary system of two M-type dwarf stars, each with about 45% of the Sun's mass and emitting only 2% of its energy.

A tiny population of neurons known to be important to appetite appear to also have a significant role in depression that results from unpredictable, chronic stress, scientists say.

These AgRP neurons reside exclusively in the bottom portion of the hypothalamus called the arcuate nucleus, or ARC, and are known to be important to energy homeostasis in the body as well prompting us to pick up a fork when we are hungry and see food.

Now Medical College of Georgia scientists and their colleagues report the first evidence that, not short-term stress, like a series of tough college exams, rather chronic, unpredictable stress like that which erupts in our personal and professional lives, induces changes in the function of AgRP neurons that may contribute to depression, they write.

The small number of AgRP neurons likely are logical treatment targets for depression, says Dr. Xin-Yun Lu, chair of the Department of Neuroscience and Regenerative Medicine at MCG at Augusta University and Georgia Research Alliance Eminent Scholar in Translational Neuroscience.

While it's too early to say if the shift in neuron activity prompted by chronic stress and associated with depression starts with these neurons, they are a definite and likely key piece of the puzzle, says Lu, corresponding author of the study in the journal Molecular Psychiatry.

"It is clear that when we manipulate these neurons, it changes behavioral reactions," she says, but many questions remain, like how these AgRP neurons in the human brain help us cope with and adapt to unpredictable chronic stress over time.

They have shown this type of stress, which results in an animal model of depression, decreases the activity of AgRP, or agouti-related protein, neurons, decreasing the neurons' ability to spontaneously fire, increasing firing irregularities and otherwise altering the usual firing properties of AgRP neurons in both their male and female mouse model of depression.

Additionally, when they used a small molecule to directly inhibit the neurons, it increased their susceptibility to chronic, unpredictable stress, inducing depression-like behavior in the mice, including reducing usual desires for rewards like consuming palatable sucrose and sex. When they activated the neurons, it reversed classic depressive behaviors like despair and the inability to experience pleasure.

"We can remotely stimulate those neurons and reverse depression," Lu says, using a synthetic small molecule agonist that binds to an also manmade chemogenetic receptor in their target neurons -- a common method for studying the relationship between behavior and particular neurons -- delivered directly to those neurons via a viral vector.

As in life, unpredictability can increase stress' impact, Lu says, so they also used that approach in their studies, with techniques like social isolation and switching light and dark cycles, and found that mice began exhibiting depressive behavior by 10 days.

The scientists found that the stress-related decrease in AgRP neuron activity seems to produce an increase in the activity of other nearby neuron types in the ARC, and are pursuing that observation further. They also are looking at adjustments that may happen to other neurons that respond to stress and reward in other subregions of the hypothalamus as well as other parts of the brain to help define the circuitry involved.

They also already are looking at the more time-consuming process of assessing whether removing the chronic stressors alone will also eventually result in the AgRP neurons resuming more normal activity.

Major depression is one of the most common mental health disorders in the United States, according to the National Institute of Mental Health, with an estimated 17.3 million adults experiencing at least one episode. Prevalence rates are highest among 18-25 year olds, females having about twice the risk of men, and depression can run in families.

Only about one-third of patients achieve full remission with existing treatments and anhedonia, the inability to experience pleasure, which increases suicide risk, typically is the last symptom to resolve. However, mechanisms behind depression's effects remain poorly understood, the scientists say.

"We want to find better ways to treat it, including more targeted treatments that may reduce side effects, which often are significant enough to prompt patients to stop taking them," Lu says. Undesirable effects can include weight gain and insomnia.

Prozac, for example, reduces the uptake of serotonin, a neurotransmitter involved in mood regulation, but serotonin also has important functions like regulating the sleep cycle, and sleep disturbances are an established side effect of selective serotonin-reuptake inhibitors.

While it's unknown if some of the existing antidepressants happen to impact AgRP neurons, it's possible that new therapies designed to target the neurons could also produce weight gain because of the neurons' role in feeding behavior and metabolism, Lu notes.

Lu was among the scientists who earlier characterized the network of AgRP neurons in the brain, and was the first to show fluctuations in the production of AgRP over the course of the day and that a surge of glucocorticoid stress hormones comes before peak expression of AgRP and feeding.

The new study shows that AgRP neurons are a key component to the neural circuitry underlying depression-like behavior, they write, and chronic stress causes AgRP dysfunction. They suspect one reason for the reduced excitability of the neurons is increased sensitivity to the inhibitory neurotransmitter GABA.

AgRP neurons are stimulated by hunger signals and inhibited by satiety. Previous studies have shown that when activated, AgRP neurons can produce significant increases in eating that can result in significant weight gain. Activating these neurons in mice, in fact, increases their eating and food seeking. Just the presence of food increases the firing of AgRP neurons, reinforcing that you are hungry and driving you to pick up that fork, Lu says of the neuron sometimes dubbed the hanger neuron.

Eliminating AgRP neurons conversely suppresses feeding and has been shown to enhance anorexia.

In a recent article in the Journal of Osteopathic Medicine, authors gathered previously published research to summarize current thinking on the feasibility and efficacy of using scent detection dogs to screen for the COVID-19 virus. The researchers report that sensitivity, specificity, and overall success rates reported by the canine scent detection studies are comparable or better than the standard RT-PCR and antigen testing procedures.

These findings indicate scent detection dogs can likely be used to effectively screen and identify individuals infected with the COVID-19 virus in hospitals, senior care facilities, schools, universities, airports, and even large public gatherings for sporting events and concerts.

"Accurate and rapid screening of individuals who may be carriers, symptomatic or asymptotic, of the COVID-19 virus will remain important for slowing and limiting the spread of infection," said Tommy Dickey, PhD, professor, University of California, Santa Barbara. "These preliminary studies suggest the use of medical scent detection dogs offers a promising approach."

Documented success detecting disease

Dogs can sense a broad range of molecules with extremely small concentrations: 1 part in a quadrillion compared with 1 part in 1 billion for humans. This capability is used for search and for identification of diseases with their individual chemistries and odors.

Using inhaled air molecules and particulates, dogs can detect odorous human molecules (volatile organic compounds, or VOCs) that originate from flaked off skin or hair cells, blood, breath, saliva, sweat, tears, nasal mucous, urine, semen, or feces. Since smells linger, dogs can maintain a historical library of the smells of complex molecules.

"The science behind and efficacy of using dogs in detecting medical conditions and diseases such as cancers, diabetes, malaria, Parkinson's disease, and more has been documented," said Heather Junqueira. "These new studies provide support for additional research to determine their ability to detect COVID-19 at scale."

The qualified studies

For their review, the authors assessed four recent studies analyzing the success of scent detecting dogs at identifying VOCs associated with COVID-19. First, they described the work of a team of collaborating researchers from France and Lebanon, who tested with 8 dogs that had previously been trained to detect both explosives and colon cancer.

These dogs were independently presented with cotton or wool gauze samples that had been soaked with sweat from one of 198 human armpits of patients in different hospitals. While the COVID-19 virus does not itself have a smell, researchers hypothesized that the resulting infection generates metabolic changes, which cause the release of a distinctive type of sweat odor that can be detected by a dog.

The dogs were trained to only sit in front of a COVID-19-positive sample contained in a box with a sample canister. After four days of training using COVID-19 samples, the success rate for the dogs ranged between 83 and 100%.

Saliva or tracheobronchial secretions

In another study described by the authors, a research team in Germany conducted a randomized, double-blinded, controlled pilot study to determine whether previously trained scent dogs could successfully detect the presence of the COVID-19 virus. Dogs were trained over 1 week to detect the COVID-19 virus in samples of saliva or tracheobronchial secretions collected from infected patients.

Each dog, its handler, and the person observing the study were blindfolded. The number and duration of each dogs' "nose dips" into the scent holes, along with the location of the positive and negative samples, were automatically recorded and verified using time-stamped video analysis, which automated the process and reduced trainer interference.

The results, derived from 1,012 automated sample presentations, showed an overall average detection rate of 94%: 157 correct indications of positive, 792 correct rejections of negative, 33 false positives, and 30 false negative indications. Interestingly, the team reported no notable difference in detection ability between the use of sample saliva and sample tracheal secretion.

While that pilot study had limitations--in particular, the positive samples came only from severely affected, hospitalized COVID-19 patients and the negative samples were from healthy individuals with no indications of respiratory infections--the authors of the present study found those results encouraging.

Support for additional research

A third study done by a team in Colombia tested 6 trained scent dogs of various and mixed breeds to develop a screening method for detecting COVID-19 in individuals who may be asymptomatic, pre-symptomatic, or symptomatic.

The researchers developed a device to safely expose the scent-trained dogs to VOC samples collected from respiratory secretions of COVID-19-positive patients, and their detailed study was conducted in 3 phases, with the third phase ongoing.

"Of the 6,000 samples, the dogs' performances [in that study] resulted in a sensitivity of 95.5% and a selectivity of 99.6%," said Dickey. "The high success rates among different types of dogs suggests a range of breeds or mixed breeds may be trained to effectively screen for COVID-19."

Challenges remain

"The results of recently reported and ongoing research are encouraging; however, there remain challenges to be considered before broad-scale implementation of scent detecting dogs to identify and screen for COVID-19," said Junqueira. "Nonetheless, the research supports the use of scent detection dogs for pilot COVID-19 screening studies in venues such as airports and sporting events."

The authors hope that their research review, which presented recent information and perspectives on the potential for broad application of trained scent dogs for screening of COVID-19-infected individuals, can be used to assist in the development of future studies and implementation of screening programs to benefit preventative medical research.

Palo Alto, CA-- Understanding how plants respond to stressful environmental conditions is crucial to developing effective strategies for protecting important agricultural crops from a changing climate. New research led by Carnegie's Zhiyong Wang, Shouling, Xu, and Yang Bi reveals an important process by which plants switch between amplified and dampened stress responses. Their work is published by Nature Communications.

To survive in a changing environment, plants must choose between different response strategies, which are based on both external environmental factors and internal nutritional and energy demands. For example, a plant might either delay or accelerate its lifecycle, depending on the availability of the stored sugars that make up its energy supply.

"We know plants are able to modulate their response to environmental stresses based on whether or not nutrients are available," Wang explained. "But the molecular mechanisms by which they accomplish this fine tuning are poorly understood."

For years, Carnegie plant biologists have been building a treasure trove of research on a system by which plants sense available nutrients. It is a sugar molecule that gets tacked onto proteins and alters their activities. Called O-linked N-Acetylglucosamine, or O-GlcNAc, this sugar tag is associated with changes in gene expression, cellular growth, and cell differentiation in both animals and plants.

The functions of O-GlcNAc are well studied in the context of human diseases, such as obesity, cancer, and neurodegeneration, but are much less understood in plants. In 2017, the Carnegie-led team identified for the first time hundreds of plant proteins modified by O-GlcNAc, providing a framework for fully parsing the nutrient-sensing network it controls.

In this most recent report, researchers from Wang's lab--lead author Bi, Zhiping Deng, Dasha Savage, Thomas Hartwig, and Sunita Patil--and Xu's lab--Ruben Shrestha and Su Hyun Hong--revealed that one of the proteins modified by an O-GlcNAc tag provides a cellular physiological link between sugar availability and stress response. It is an evolutionarily conserved protein named Apoptotic Chromatin Condensation Inducer in the Nucleus, or Acinus, which is known in mammals to play numerous roles in the storage and processing of a cell's genetic material.

Through a comprehensive set of genetic, genomic, and proteomic experiments, the Carnegie team demonstrated that in plants Acinus forms a similar protein complex as its mammalian counterpart and plays a unique role in regulating stress responses and key developmental transitions, such as seed germination and flowering. The work further demonstrates that sugar modification of the Acinus protein allows nutrient availability to modulate a plant's sensitivity to environmental stresses and to control seed germination and flowering time.

"Our research illustrates how plants use the sugar sensing mechanisms to fine tune stress responses," Xu explained. "Our findings suggest that plants choose different stress response strategies based on nutrient availability to maximize their survival in different stress conditions."

Looking forward, the researchers want to study more proteins that are tagged by O-GlcNAc and better understand how this important system could be harnessed to fight hunger.

"Understanding how plants make cellular decisions by integrating environmental and internal information is important for improving plant resilience and productivity in a changing climate," Wang concluded. "Considering that many parts of the molecular circuit are conserved in plant and human cells, our research findings can lead to improvement of not only agriculture and ecosystems, but also of human health."