Culture

Discovered by Victor Hess in 1912, cosmic rays, relativisitic particles that shower Earth, contribute a signicant part of the energy density in the universe and carries unambiguous informations on various astrophysical processes . Yet until now, origin of cosmic rays is still a mystery.

A key problem in understanding the origin of cosmic rays is the searching for the acceleration site up to or even beyond Ultra-high energy (UHE). Such extreme accelerators are dubbed as PeVatrons. However, composed of subatomic particles, such as protons or atomic nuclei, cosmic rays are charged and lose the direction information in propagating in the magnetic field in the interstellar medium, which make it impossible to identify the PeVatrons from direct cosmic ray measurement. On the other hand, UHE γ-rays, those fall in peta-electronvolt (1015 eV) range, are produced unavoidably inside or in the vicinity of PeVatrons. γ-rays are not charged and travel straight , thus they can be regarded as the straightforward signature to identify PeVatrons.

A new observatory, the Large High Altitude Air Shower Observatory (LHAASO) located at Sichuan, China, detected dozen Ultra-high Energy gamma-ray sources, opening a new window into the γ-ray sky, which indicate that the existence of a population of PeVatrons in our Galaxy.

In this article, though not fully installed, the half Kilometer Square Array (KM2A), one of the three interconnected detectors that constitute LHAASO, reported 12 PeVatrons with the statistical significance greater than 7 standard devition after observation using 11 months data. Of these sources, two have been detected with energy over 0.8 PeV, an energy equivilant to accelerate an electron with electric potential of 0.8 million billion electronvolts, and one with highest energy exceeded 1.4 PeV.

The 12 γ-ray emitting regions identified by LHAASO prompts the presence of active or recent PeVatrons. Team led by Professor YANG Ruizhi from the University of Science and Technology of China discussed some possible candidates, including pulsar wind nebulae, supernova remnants and star-forming regions, with multi-wavelength data.

To support the detection of UHE γ-rays, the team led by Professor LI Cheng from the University was responsible for the design and quality assurance/check of over 3000 high-dynamic-range large-size photodetectors for muon detectors of KM2A and Water Cherenkov Detector Array (WCDA), another component of LHAASO.

The team led by Professor AN Qi from the University designed, tested, and installed the readout electronics system for the 8'' and 20'' PMTs in WCDA, which achieves high precsion time and charge measurement over a large input dynamic range of 1 Photon Electron (P.E.) ~4000/2000 P.E..

Full article was published on Nature.

With comprehensive multi-wavelength data, researcher will be able to firmly identify and locate PeVatrons in the future. Longer observation and full installation of LHAASO is also expected to provide more detailed information on reported PeVatrons and to discover even more PeVatrons, which would advance the understanding of the origin of cosmic rays.

Press release - Abstract 481: Effects of testosterone therapy on morphology and grade of NAFLD in obese men with functional hypogonadism and type 2 diabetes

According to a new study, testosterone therapy may reduce non-alcoholic fatty liver disease in obese men with functional hypogonadism and type-2 diabetes.

Testosterone therapy may help obese men with functional hypogonadism and type-2 diabetes reduce the prevalence of non-alcoholic fatty liver disease (NAFLD), according to a study being presented at the 23rd?European Congress of Endocrinology (e-ECE 2021), on Tuesday 25 May 2021 at 14:00 CET (http://www.ece2021.org). The two-year study found that therapy with testosterone undecanoate normalised testosterone levels, reduced NAFLD, and suppressed the symptoms of hypogonadism in men living with these conditions.

NAFLD is emerging as a public health issue worldwide. It is estimated that prevalent cases will increase 21% by 2030, from 83.1 million to 100.9 million. NAFLD is more commonly found in people with type-2 diabetes, and is linked to obesity, insulin resistance and atherogenic dyslipidemia. NAFLD refers to excess fat accumulation in the liver, in the absence of excessive alcohol consumption. Alcohol consumption of less than 30 g (3.75 units) per day for men is used as the cut-off to diagnose NAFLD. As an increasing global health issue, this study and its findings may be a promising area for further research.

Dr Kristina Groti Antonic and her team from the University of Ljubljana, Slovenia, carried out a large study on the effects of testosterone therapy on glycemic control, metabolic parameters, vascular function and morphology in obese men with hypogonadism and type-2 diabetes mellitus. They presented a part of this study at e-ECE 2021 in which they evaluated the effects of testosterone therapy on morphology and grade of NAFLD in this population. The two-year clinical trial saw 55 males with functional hypogonadism and type-2 diabetes participate. The first year focused on a double blind, placebo-controlled study and the following year was used for follow-up.

During the study, the participants were randomised into two groups. The first group received testosterone undecanoate during both years of the study, while the second group received a placebo in the first year and testosterone therapy in the second year. A range of tests including testosterone levels, prostate specific antigen and routine blood tests were assessed at the beginning of the trial, 12 and 24 months. Liver ultrasounds for NAFLD grade assessments were performed at the beginning and after two years, which showed an improvement in NAFLD grades after two years of the trial.

Dr Kristina Groti Antonic shared that, "improvement of NAFLD grade was a result of improved insulin resistance, reduction in body mass index and body weight, along with changes in body composition. As we know, testosterone increases lean body mass at the expense of fat mass, either alone or in combination with behavioral and lifestyle modifications. Testosterone with its anti-inflammatory effects also reduced chronic inflammatory state in the liver. Our study shows that testosterone therapy could be used as a suitable therapy for obese men living with non-alcoholic fatty liver disease, and therefore the findings can be used to tackle this growing pandemic."

This knowledge could help obese men living with functional hypogonadism and type-2 diabetes experience normalised testosterone levels and reduced prevalence of non-alcoholic fatty liver disease.

Summary: A new study published by the open access publisher Frontiers shows the usefulness of opportunistically collected specimens, such as stranded carcasses, to study elusive species. The researchers used stable isotope analysis of skin, muscle, and bone tissue of Sowerby’s beaked whales to study their spatial ecology. They found that the species exhibits both short- and long-term habitat fidelity. The results are published in Frontiers in Conservation Science and show the importance of such studies for marine wildlife conservation.

A mysterious whale species

Beaked whales, a species of toothed whales, make up more than 25% of extant cetaceans (dolphins, porpoises, and whales), but are elusive and notoriously difficult to study. They live in deep waters and stay away from shores. Due to a lack of observations from the wild, little is known about their ecology and biology. Because of this, they are considered 'data deficient' by the IUCN Red List and developing conservation plans is challenging.

Some species of beaked whales have never been observed alive and are only known from stranded carcasses. "Beaked whales are really cool, but most people haven't heard of them because they are so enigmatic. Whales are generally large and charismatic - we can go on whale watching trips and see them in the wild, yet there are entire groups of whale species we know almost nothing about," says Dr Kerri Smith, of the University of Texas El Paso and the Smithsonian National Museum of Natural History, United States.

Sowerby's beaked whales (Mesoplodon bidens) were first described more than 200 years ago, yet little is known about this species. The species' geographic range is thought to cover much of the North Atlantic Ocean. Stranded animals have been collected from both North American and European waters, but it is unknown if the species is structured into spatially separate subpopulations or if there is one continuous and highly mobile population.

Stable isotope analysis to study elusive animals

Stable isotopes get incorporated into different tissue types through diet. The rate at which stable isotopes get incorporated into a tissue depends on the tissue's growth and replacement rates. For example, skin turnover rates are faster than those of muscle, which in turn are faster than the turnover of bone. Stable isotope analysis is an efficient tool that can be used when traditional techniques, such as GPS tracking and camera recording from field observations, can't be applied. It can be used to answer ecological and biological questions about a species' diet or spatial origin across time.

To better understand the species' spatial range, the researchers measured the carbon isotope (δ13C) and nitrogen isotope (δ15N) composition of skin, muscle, and bone tissue of Sowerby's beaked whales from the east and west Atlantic. The 102 samples were collected from museum specimens, stranded carcasses, and bycaught animals, and included females and males from all ages.

A treasure trove of data

When researchers work with specimens of opportunity, there is little control over how samples were collected. "In our study, the majority of our specimens came from strandings and fisheries bycatch; since these specimens represent only a small portion of all Sowerby's beaked whales, we only have a few pieces of a large, complex puzzle. Those pieces can tell us a lot, however, and the more we study these whales, the more we will learn about their distributions, behavior, and lives."

The results show that there are at least two subpopulations of Sowerby's beaked whales, one each in the eastern and western Atlantic. "Our study has two major results. First, it demonstrates the power of specimens of opportunity to answer fundamental ecological questions - these specimens are treasure troves of data waiting for someone to query them," says Smith. "Second, it provides some of the first data about Sowerby's beaked whale long-term distribution and population structure, something that would be nearly impossible to learn by studying living whales in their habitat. We can learn a lot about beaked whale ecology from specimens of opportunity." The researchers suggest genetic analysis to explore possible genetic differentiation between the two populations.

The findings have implications for marine wildlife conservation. The two populations found here likely have different conservation needs. Smith concludes: "A key action to take going forward is generating more fundamental data through studies like this one - successful conservation action requires a strong foundation of reliable data, and there is still so much we do not know about beaked whales and many other marine species. As we learn more about them and their habitats, we may need to set aside important habitats as marine protected areas. Additional research to identify the potential influence of fishing activities and naval sonar on critical beaked whale habitats is also needed."

What The Study Did: This study evaluates the association between bitter taste receptor types (supertasters who experience greater intensity of bitter tastes; tasters; and nontasters who experience low intensity of bitter tastes or no bitter tastes) and outcomes after infection with SARS-CoV-2.

Authors: Henry P. Barham, MD, Sinus and Nasal Specialists of Louisiana in Baton Rouge, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2021.11410)

Editor's Note: The article includes conflict of interest disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.

What The Study Did: Researchers examined if circulating sex hormones are associated with disease severity in patients with COVID-19.

Authors: Sandeep Dhindsa, M.D., of the St Louis University School of Medicine and Abhinav Diwan, M.D., of the Washington University School of Medicine, both in St. Louis, are the corresponding authors.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2021.11398)

Editor's Note: The article includes conflict of interest and funding/support disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.

What The Study Did: Rates of depression, anxiety, suicidal thoughts and posttraumatic stress disorder among current and former coal miners in the United States were examined in this study.

Authors: Drew Harris, M.D., of the University of Virginia in Charlottesville, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2021.11110)

Editor's Note: The article includes conflict of interest disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.

While we sleep, the brain produces particular activation patterns. When two of these patterns - slow oscillations and sleep spindles - gear into each other, previous experiences are reactivated. The stronger the reactivation, the clearer will be our recall of past events, a new study reveals.

Scientists have long known that slow oscillations (SOs) and sleep spindles - sudden half-second to two-second bursts of oscillatory brain activity - play an important role in the formation and retention of new memories.

But experts in the UK and Germany have discovered that the precise combination of SOs and sleep spindles is vital for opening windows during which memories are reactivated; helping to form and cement memories in the human brain.

Researchers at the University of Birmingham and Ludwig-Maximilians-University Munich today published their findings in Nature Communications.

Co-author Dr Bernhard Staresina, from the University of Birmingham's School of Psychology, commented: "Our main means of strengthening memories while we sleep is the reactivation of previously learnt information, which allows us to solidify memories in neocortical long-term stores.

"We have discovered an intricate interplay of brain activity - slow oscillations and sleep spindles - which create windows of opportunity enabling this reactivation."

Co-author Dr Thomas Schreiner, from Ludwig-Maximilians-University, Munich, commented: "Memory reactivation is specifically bound to the presence of SO-spindle complexes. These results shed new light on the memory function of sleep in humans and emphasise the importance of orchestrated sleep rhythms in strengthening our powers of recall and orchestrating the creation of memories."

Before this study, evidence of the brain's capacity to reactivate memories during sleep was scarce, but the team devised novel tests where participants were shown information before taking a nap and closely monitored brain activity during non-rapid eye movement (NREM) sleep using EEG recording. Those taking part were then tested on their memory recall after waking up, allowing the researchers to link the extent of memory reactivation during sleep to memory performance.

The results revealed reactivation of learning material during SO-spindle complexes, with the precision of SO-spindle coupling predicting how strongly the memory would be reactivated by the brain. This in turn predicted the level of memory consolidation across participants and the subsequent clarity of recall.

HOUSTON - (May 25, 2021) - Sometimes things are a little out of whack, and it turns out to be exactly what you need.

That was the case when orthoferrite crystals turned up at a Rice University laboratory slightly misaligned. Those crystals inadvertently became the basis of a discovery that should resonate with researchers studying spintronics-based quantum technology.

Rice physicist Junichiro Kono, alumnus Takuma Makihara and their collaborators found an orthoferrite material, in this case yttrium iron oxide, placed in a high magnetic field showed uniquely tunable, ultrastrong interactions between magnons in the crystal.

Orthoferrites are iron oxide crystals with the addition of one or more rare-earth elements.

Magnons are quasiparticles, ghostly constructs that represent the collective excitation of electron spin in a crystal lattice.

What one has to do with the other is the basis of a study that appears in Nature Communications, where Kono and his team describe an unusual coupling between two magnons dominated by antiresonance, through which both magnons gain or lose energy simultaneously.

Usually, when two oscillators resonantly couple, one gains energy at the expense of the other, conserving total energy, Kono said.

But in antiresonant (or counterrotating) coupling, both oscillators can gain or lose energy at the same time through interaction with the quantum vacuum, the zero-point field predicted to exist by quantum mechanics.

Think of it as an ephemeral seesaw that can be forced to bend in the middle.

Makihara and co-authors Kenji Hayashida of Hokkaido University and physicist Motoaki Bamba of Kyoto University used the discovery to show via theory the likelihood of significant quantum squeezing in the ground state of the coupled magnon-magnon system.

In the squeezed state, the amount of fluctuation, or noise, of a measurable quantity associated with the magnons can be suppressed, with simultaneously increased noise in another quantity, Kono said. "It's related to the Heisenberg uncertainty principle in which a set of variables is correlated, but if you try to precisely measure one, you lose information about the other. If you squeeze one, uncertainty about the other grows.

"Usually, in order to create a quantum squeezed state, one has to strongly drive the system using a laser beam. But Takuma's system is intrinsically squeezed; that is, it can be described as an already squeezed state," he said. "This could become a useful platform for quantum sensing applications."

Makihara said the unique state is achieved with a strong magnetic field like that used in magnetic resonance imaging. The field applies torque to the magnetic moments in atoms, in this case those of the orthoferrite. That causes them to rotate (or precess).

That takes a powerful field. The Kono lab's RAMBO -- the Rice Advanced Magnet with Broadband Optics -- is a unique spectrometer developed with physicist Hiroyuki Nojiri at Tohoku University that allows researchers to expose materials cooled to near absolute zero to powerful magnetic fields up to 30 tesla in combination with ultrashort laser pulses.

"We were saying, 'What can we study with RAMBO? What new physics is there in this unique regime?'" said Makihara, now a graduate student at Stanford University. "Orthoferrites have these magnons that shift up to 30 tesla and frequencies in the terahertz regime. The initial measurements weren't that interesting.

"But then we received crystals (grown by Shanghai University physicist Shixun Cao and his group) that didn't have perfectly parallel faces," he said. "They were kind of cut at an angle. And one day, we loaded the crystal on the magnet at such an angle that the magnetic field was not applied along the crystal axis.

"We expected the magnon frequency to just shift up with the magnetic field, but when it was tilted, we saw a small gap," Makihara said. "So, after discussing this finding with Professor Bamba, we explicitly requested crystals that were cut at different angles and measured those, and saw this huge degree of anti-crossing. That's the signature of ultrastrong coupling."

Antiresonance always exists in light-matter and matter-matter interactions but is a minor presence compared to the dominant resonant interaction, the researchers noted. That was not the case with the orthoferrites studied by the Kono lab.

Exposing the material to a high magnetic field and tilting the crystal with respect to the field pumped antiresonance that equaled and even surpassed the resonance.

If additional rotating magnetic fields (for instance, from circularly polarized light) are introduced, the precessing moments strongly interact with fields that rotate with the moments (the co-rotating fields), whereas they weakly interact with fields that rotate in the opposite directions (the counterrotating fields).

In quantum theory, Bamba said, these so-called counterrotating interactions lead to bizarre interactions where both the light and matter subsystems can gain or lose energy at the same time. The interactions between the magnetic moments and the counterrotating fields are considered antiresonant and normally have little effect. However, in the matter-matter coupled system studied at Rice, the antiresonant interactions could be made dominant.

"The strength of the co-rotating and counterrotating interactions is usually a fixed constant in a system, and the effects of the co-rotating interactions always dominate those of the counterrotating interactions," Kono said. "But this system is counterintuitive because there are two independent coupling strengths, and they are incredibly tunable via crystal orientation and magnetic field strength. We can create a novel situation where effects from the counterrotating terms are more dominant than from the co-rotating terms.

"In light-matter systems, when the frequencies of light and matter become equal, they mix together to form a polariton," he said. "Something similar happens in our case, but it's between matter and matter. Two magnon modes hybridize. There is a long-standing question of what happens when the degree of hybridization becomes so high that it even exceeds the resonance energy.

"In such a regime, exotic phenomena are predicted to occur due to counterrotating interactions, including a squeezed vacuum state and a phase transition into a novel state where static fields spontaneously appear," he said. "And we found that we can achieve such conditions by tuning the magnetic field."

The new study advances the Kono team's efforts to observe the Dicke superradiant phase transition, a phenomenon that could create a new exotic state of matter and lead to advances in quantum memory and transduction. The lab found a promising approach for realizing it in matter-matter coupling in 2018, reporting its discovery in Science.

The discovery also demonstrates that orthoferrite in a magnetic field could serve as a quantum simulator, a simple and highly tunable quantum system that represents a more complex one with an intractable number of interacting particles or an experimentally inaccessible regime of parameters, Kono said.

Tunable magnon-magnon coupling in orthoferrites can be used to provide insight into the nature of the ground state of an ultrastrong, coupled light-matter hybrid, he said.

Kono said their findings will also prompt a search for more materials that exhibit the effect. "Rare-earth orthoferrites is a big family of materials, and we studied just one," he said.

Researchers from University of Sydney, University of Florida, and Rutgers University published a new paper in the Journal of Marketing that examines the role of serendipity in customer satisfaction and how marketers can provide it.

The study, forthcoming in the Journal of Marketing, is titled "Serendipity: Chance Encounters in the Marketplace Enhance Consumer Satisfaction" and is authored by Aekyoung Kim, Felipe Affonso, Juliano Laran, and Kristina Durante.

Netflix knows you are tired of choice. The streaming service recently introduced what might be the perfect hack: a shuffle button that eliminates choice and plays a randomly selected program for the consumer. Under COVID-19 restrictions, the newly homebound were happy to have so many programming options, but this faded over time.

Recall a time when you heard a beloved song come across the radio or stumbled upon a favorite movie while channel surfing. These accidents become "happy" because they lead to feelings of serendipity, which our new research shows heighten enjoyment. When a product, service, or experience is positive, unexpected, and involving chance, our research team reasoned that this would generate congruent feelings. Consumers would feel that the encounter was a good surprise, make attributions to chance, and feel lucky that it happened--which we collectively call "feelings of serendipity." Using a series of experiments, we set out to test our contention that marketers can create serendipity in the marketplace.

Across multiple consumer domains (online subscription services, museums, movies, food consumption, and music), creating serendipity through positive, unexpected, chance encounters increased satisfaction, enjoyment, perceptions of meaningfulness, willingness to pay, willingness to recommend a service, and interest. For example, members of subscription box services (e.g., Birchbox, Stitchfix) enjoyed their assortment more when they received a random selection of products compared to members who made selections themselves. A similar phenomenon occurred during the researchers' curated experiments. For instance, they measured consumer satisfaction using two platforms; one delivering movie recommendations and another delivering music recommendations. As Kim explains, "Compared to a condition where consumers chose for themselves, enjoyment increased when consumers received a movie or song delivered at random from a set of alternatives we had previously selected. Increased enjoyment occurred because the seemingly randomly delivered product was thought to be a good surprise, attributed to chance and luck. In other words, serendipity was born."

This good news suggests that marketers can capitalize on the power of serendipity to increase consumer satisfaction. To do this, marketers must go beyond surprising consumers, because serendipity is not just a pleasant surprise. To test the depths of serendipity, the research team carefully removed one or more of the "ingredients" to see if the serendipity effect would go away. First, they found that when an encounter was negative, consumers no longer felt increased enjoyment. In fact, there was a boomerang effect. A negative encounter that was unexpected and attributed to chance was perceived to be even more negative.

Second, when they increased and decreased the degree of randomness, it exacerbated and attenuated serendipity. Consumers who viewed a movie trailer that was described as randomly selected from 100 possible options enjoyed it more than when it came from a menu of 10 options, which made it seem less random. Moreover, making consumers aware that a marketer was selecting the options also decreased serendipity and enjoyment, because now it was clear that someone was behind the curtain and the selection was not random.

Finally, they reasoned that educating consumers about a product or service would eliminate the serendipity effect. Affonso says that "Coming to learn more about a product not only eliminates unexpectedness (a key ingredient for serendipity), but can create a sense of expertise that leads consumers to think they have the knowledge to make better choices." In one experiment, they used a platform that recommends functional music that can enhance focus. Approximately half of the participants were provided with information on which attributes increase a song's ability to increase people's concentration. When consumers were educated this way, encountering music from the platform in a serendipitous way later on (via random chance) no longer enhanced enjoyment. This suggests that aficionados may not appreciate marketplace serendipity as much as the rest of us.

"In today's marketplace, which affords an abundance of choice, our research provides marketers with insights on how to build some magic into marketplace encounters," says Laran. When attempting to enhance serendipity, companies may sometimes want to increase perceptions that an encounter is the result of chance or randomness. For example, consumers may enjoy some unexpected events more as part of vacation packages or enjoy product samples that arrive randomly without a lot of information. Companies should also eliminate marketing communications that highlight the targeting process, avoiding telling consumers that a product was especially selected for them based on what the company knows about their preferences. In such instances, an attribution to chance is replaced by attribution to being watched and targeted by the company.

BINGHAMTON, N.Y. - A team of evolutionary biologists including faculty at Binghamton University, State University of New York have shown that some Anolis lizards, or anoles, have adapted to rebreathe exhaled air underwater using a bubble clinging to their snouts.

Semi-aquatic anoles live along neotropical streams and frequently dive for refuge, remaining underwater for up to 16 minutes. Lindsey Swierk, assistant research professor of biological sciences at Binghamton University, documented this behavior in a Costa Rican anole species in 2019. She had been shocked to see an anole submerge itself for such long periods and used a GoPro underwater to document the behavior.

"It's easy to imagine the advantage that these small, slow anoles gain by hiding from their predators underwater - they're really hard to spot!" says Swierk. "But the real question is how they're managing to stay underwater for so long."

The researchers conducted experiments documenting routine air-based underwater respiration in several distantly related semi-aquatic anole species. They found that semi-aquatic anoles can respire underwater by ''rebreathing'' exhaled air that is trapped between their skin and surrounding water.

"We found that semi-aquatic anoles exhale air into a bubble that clings to their skin," said lead author Chris Boccia, a recent master of science graduate from the University of Toronto. "The lizards then re-inhale the air, a maneuver we've termed 'rebreathing' after the scuba-diving technology."

The researchers believe that hydrophobic skin, which they observed in all sampled anoles, may have been exaptative, facilitating the repeated evolution of specialized rebreathing in species that regularly dive. Their analyses strongly suggest that specialized rebreathing is adaptive for semi-aquatic habitat specialists. Air-based rebreathing may enhance dive performance by incorporating dead space air from the buccal cavity or plastron into the lungs, facilitating clearance of carbon dioxide, or allowing uptake of oxygen from surrounding water (i.e., a ''physical gill'' mechanism.) The team used an oxygen sensor inside the rebreathed bubbles to determine whether anoles were consuming oxygen from the bubble. In true "scuba-tank" fashion, the researchers discovered that the oxygen concentration in an anole's air bubble decreases over the length of the dive, in support of this idea.

"The finding that different species of semi-aquatic anoles have evolutionarily converged to extract oxygen from their rebreathed air bubbles leads to other exciting questions," says Swierk. "For example, the rate of oxygen consumption from the bubble decreases the longer an anole dives, which could possibly be explained a reduction in an anole's metabolic rate with increased dive time." Binghamton graduate student co-author, Alexandra Martin, is currently exploring whether body cooling during dives may help explain this phenomenon.

"Rebreathing had never been considered as a potential natural mechanism for underwater respiration in vertebrates," says Luke Mahler, an assistant professor in EEB at the University of Toronto and Boccia's thesis supervisor. "But our work shows that this is possible and that anoles have deployed this strategy repeatedly in species that use aquatic habitats."

Swierk and Mahler are planning future projects to better understand the evolution of the physiology and behavior related to rebreathing. "Anoles are a remarkable group of lizards, and the number of ways that this taxon has diversified to take advantage of their environments is mind-boggling," said Swierk.

COLUMBUS, Ohio - A comprehensive analysis of 437 studies from around the world provides the best evidence to date that narcissism is an important risk factor for both aggression and violence, researchers said.

The link between narcissism and aggression was found for all dimensions of narcissism and for a variety of types of aggression. Results were similar regardless of gender, age, whether they were college students, or country of residence.

And, to have an impact, narcissism doesn't have to be at levels so high as to be pathological. Findings showed that even when narcissism was within what is considered a normal range, higher levels were linked to aggression.

"It is a pretty straightforward message: Narcissism is a significant risk factor for aggressive and violent behavior across the board," said Brad Bushman, co-author of the study and professor of communication at The Ohio State University.

The study was led by Sophie Kjaervik, a graduate student in communication at Ohio State. It was published yesterday (May 24, 2021) in the journal Psychological Bulletin.

"The link we found between narcissism and aggression was significant - it was not trivial in size," Kjaervik said. "The findings have important real-world implications."

The researchers combined and analyzed data from many studies to provide a comprehensive view of this research area. In this meta-analysis, they examined data from 437 independent studies with a total of 123,043 participants.

Narcissism is characterized by an overblown sense of self-importance, Bushman said. The key component of narcissism is entitlement. Narcissism also has two peripheral components: grandiose (those with high self-esteem) and vulnerable (those with low self-esteem). The study found all of these components were linked to aggression.

Narcissism was related to all forms of aggression measured in the studies the researchers analyzed, including physical, verbal, bullying, direct or indirect, and displaced onto innocent targets.

"Individuals who are high in narcissism are not particularly picky when it comes to how they attack others," Kjaervik said.

Findings showed that narcissism was linked to online cyberbullying, as well as bullying offline.

"That's a highly important finding now that we live in an online world," she said.

People higher in narcissism were not only more likely to lash out in anger, but were also more likely to be "cold, deliberate and proactive" in their aggression, Bushman said.

People high in narcissism were more likely than others to be aggressive whether they were provoked or not, the study found. But the risk for aggression was significantly higher when they felt provoked, such as being ignored or insulted.

The researchers were somewhat surprised to find that the link between narcissism and violence was nearly as strong as its link with less serious forms of aggression. Violence is more rare than and is generally more difficult to predict than lesser forms of aggression, Bushman said. In this study, violence was defined as aggression intended to cause physical harm such as injury or death.

But these results are consistent with research suggesting that narcissism might be a risk factor for extremely violent acts such as mass shootings, he said.

One argument could be that the narcissism-aggression link would be more likely to occur in individualistic countries, like the United States, where people emphasize their personal rights. But the analysis found that narcissism and aggression were related even in more collectivist countries.

And findings were similar whether the research participants were college students or a more general population.

It might be tempting to think these results apply only to people who are "narcissists," but that would be wrong, Bushman said.

For one, you can't separate people into those who are narcissists and those who are not. Nearly everyone has some degree of narcissism, even though only a minority have levels high enough to be called pathological.

Findings in this study suggest that higher levels of narcissism are related to more aggression even before it reaches pathological levels.

"All of us are prone to being more aggressive when we are more narcissistic," Bushman said.

One thing that clearly stood out in the analysis, he said, was how people high in narcissism respond when they feel threatened.

"Our results suggest provocation is a key moderator of the link between narcissism and aggression," Bushman said.

"Those who are high in narcissism have thin skins, and they will lash out if they feel ignored or disrespected."

A study by Monash University and Alfred Health found a 70 per cent reduction in one type of human papillomavirus (HPV) in gay and bisexual men after the implementation of the school-based HPV vaccination program.

The HYPER2 study, published in The Lancet Infectious Diseases, and led by Associate Professor Eric Chow, found there was a significant reduction in all four vaccine-preventable genotypes in gay/bisexual men aged 16-20 years following the introduction of the vaccine for boys in 2013.

Australia is one of the first and few countries that have both boys and girls vaccination programs for HPV. The vaccine covers four genotypes: 6/11/16/18. Genotypes 6/11 cause about 90 per cent of the genital wart cases and genotypes 16/18 cause about 70 per cent of cervical and anal cancers.

This is the first study to show that the implementation of the gender-neutral program can reduce high-risk anal HPV and potentially reduce the incidence of anal cancer in gay and bisexual men.

This repeated cross-sectional study recruited 400 gay and bisexual men with a median age of 19 years from sexual health clinics and the community in Melbourne.

The results are compared with the HYPER1 group of 200 gay/bisexual men pre-vaccination in 2010-2012 and the HYPER2 group of 200 gay/bisexual men post-vaccination in 2017-2018.

It showed a reduction in anal quadrivalent genotypes from 28 per cent down to 7.3 per cent and penile quadrivalent genotypes also lower in the post-vaccination group 6.1 per cent compared to 11.9 per cent.

Anal cancer incidence has increased globally among men over the last three decades. It is overrepresented among gay and bisexual men, particularly those living with HIV.

A meta-analysis estimated the incidence of anal cancer to be 45.9 per 100,000 among HIV-positive MSM. Results from the HYPER2 study suggest that male vaccination may lead to a potential reduction in anal cancer among gay and bisexual men in Australia, which is similar to the reduction in cervical cancer among Australian women after the HPV vaccination program launched in 2007.

"Australia has a very successful HPV vaccination program for both boys and girls with high vaccine coverage," Associate Professor Chow said.

"The vaccine is effective in reducing HPV-related diseases and showing some promising evidence that this may lead to a reduction in HPV-related cancer in the future."

In the last year, one thing has become clear: we cannot live life without risk. In fact, every part of our daily routines became subject to analysis: How risky is the action and is its value worth the potential cost?

Risk analysis, though seemingly more ever-present in our thoughts today, has always been a part of how we operate and how the systems around us work. As new pressures, such as climate change, deepen, the accuracy and reliability of risk analysis models regarding issues as basic as the cleanliness of our drinking water have become more important than ever.

USC researchers, including Felipe de Barros, associate professor of civil and environmental engineering in the USC Viterbi School of Engineering, have developed a variety of models that can help assess how emerging contaminants disperse, dissolve and ultimately impact water quality and the resilience of aquifers.

"The subsurface environment is very complex and challenging to track, because we cannot see it," de Barros said. "We don't have detailed information on how deep the contaminants are, how far out they are spread, where they are coming from, what other contaminants they have mixed with or how the geological properties vary in space."

These questions are exactly what de Barros and his team work on. Recently, de Barros and collaborators developed an analytical model that can help predict contaminant spreading in fractured porous media under different water flow scenarios. This work was featured in Physics Review Fluids. The advantage of the analytical model developed by de Barros and collaborators is that it allows to look at the relationships between varying geological and physical parameters to see how they impact dissolution of a contaminant as water flows from one point to another.

"It's like studying alternative realities--like in a comic book universe," de Barros said. "If you can understand what happens with each different scenario, you can better predict outcomes in real time and better allocate resources to mitigate the problem."

"With tools like this one, you can do probabilistic risk analysis and compute and assess the risks associated with a waste disposal facility, for example, or with an accidental leak," he said. "We can also understand how fast these chemicals are going to travel in these environments."

For example, say there was a chemical spill near an aquifer. With accurate risk modeling that accounts for key heterogeneous variables in the environment, health professionals and regulatory bodies could better understand how much of a contaminant they can expect to be in the end water source, de Barros said.

"This modeling can help with questions like, 'Should I invest more money in public health or in characterizing the geological site? Should I shut down the well--which is very costly--or bring in tap water from another location or buy bottled water, or is there reasonable knowledge that the water can still be used, once treated?" he said.

A Complex System Simplified

Felipe de Barros and his team looked at the complex physics of water flow through different flow systems, namely where restricted flow, like through a porous membrane, meets free flow, like the space between two porous surfaces. How these areas interact are important in determining how a chemical dissolves or mixes in a water source, he said.

Instead of solving the physical equations numerically to model different outcomes, the team looked tackled the problem by developing analytical solutions that are computationally cheap. Identifying relationships between elements of the model allowed them to "upscale" it, simplifying the math involved by distilling these trends into fewer terms then embedded into their equation.

To create a model that encapsulated these key parameters and behaviors, the researchers looked at the geometric features of the subsurface structures. Porosity and permeability of the subsurface environment or aspect ratio characterizing the fractures were key elements that were considered, de Barros said.

Decision Making with Data

It is difficult to make decisions in a vacuum. This is why de Barros says the tools developed within his research group could change how water treatment facilities, regulators and others decide what to do in various scenarios. As surface water becomes increasingly scarce, subsurface sources and treatment options will need to be tapped into increasingly. At the same time, however, with pollution and chemical contaminants leaking into water sources, the challenge is identifying how to gauge safety of a certain flow without fully understanding the invisible unknowns impacting it.

One thing our research aims to go, de Barros said, is to develop application-oriented models that improve our fundamental understanding on the interaction between the geological media and solute transport behavior. This would allow to see how contaminant dispersion is influenced by shifting conditions. For example, how does a contaminant leak through to the other side of a cracked rock versus one that has no fissures? Because so many potential contaminants can be found in the water, this helps create a general understanding of the subsurface system without relying on knowing the exact contaminants in question.

This knowledge can also allow for reverse engineering, for example building a system to have certain hydrogeological conditions that could be help achieve a desired chemical concentration or water quality output.

"Understanding how the concentration of a chemical changes in a given system through space and time can have implications for public health, water treatment operations and also regulatory policies, for instance as issued by the U.S. EPA," de Barros said.

A study published today in Scientific Reports suggests that new health challenges may be emerging as a result of conservationists' success in pulling mountain gorillas back from the brink of extinction.

The study, the first species-wide survey of parasite infections across the entire range of the mountain gorilla, was conducted by an international science team led by the Institute of Vertebrate Biology, Czech Academy of Sciences; University of Veterinary Sciences Brno, Czech Republic; Gorilla Doctors; and the Dian Fossey Gorilla Fund. The work was conducted in collaboration with the protected area authorities of Rwanda, Uganda and the Democratic Republic of Congo (the Rwanda Development Board, the Uganda Wildlife Authority and l'Institut Congolais pour la Conservation de la Nature, respectively).

All mountain gorillas live in fully protected national parks in Rwanda, Uganda and DR Congo, where the potential for spatial expansion is extremely limited due to dense human communities living nearby. Consequently, as gorilla population densities within the protected areas increase, their susceptibility to infectious diseases may also.

The Virunga mountain gorilla population has not increased uniformly across its habitat, possibly due to varying ecological conditions that are linked to different vegetation types. Additionally, in areas of the Virunga Massif where some of the highest growth rates occurred, the mountain gorillas experienced major changes in their social structure, leading to a threefold increase in group densities.

Clinical gastrointestinal diseases linked to helminths, a type of parasitic worm, have been recorded in mountain gorilla populations in both the Virunga Massif and the Bwindi Impenetrable Forest, and may pose a threat to these endangered animals.

"Gastrointestinal disease from helminths is typically asymptomatic in wild non-human primates," said first author Dr. Klara Petrzelkova, senior researcher at the Czech Academy of Sciences. "But host and extrinsic factors can alter helminth transmission and host susceptibility. This study has put a spotlight on these factors."

The study elucidates the drivers and patterns of helminth infections and provides a comprehensive foundation for future assessments of the impact of these parasites on gorilla population dynamics. Strongylid and tapeworm infections were quantified in fecal samples collected from night nests and from individually identified gorillas living in five social groups using fecal egg counts.

"Detecting significant differences in parasite burdens among gorilla family groups is critical information for guiding our decisions in providing life-saving veterinary care for this endangered species," said Julius Nziza, head veterinarian in Rwanda for Gorilla Doctors, which is a collaboration of the Mountain Gorilla Veterinary Project and the University of California, Davis' Karen C. Drayer Wildlife Health Center.

Striking geographic differences in strongylid infections were detected, with higher egg counts measured mostly in gorillas living in areas where there has been a higher occurrence of gastrointestinal disease in gorillas. Differences in population growth rates across the Virunga Massif subpopulations and the Bwindi population, differences in the social structure of groups, especially in the Virungas, and differences in habitat characteristics (for example, vegetation types at altitudinal gradients) across the distribution range of mountain gorillas may explain observed differences in strongylid infections.

"The knowledge we acquired from this study will help develop future plans for protecting these endangered primates and their critical habitat" said Felix Ndagijimana of the Dian Fossey Gorilla Fund.

This highly collaborative study points to new challenges emerging as possible "side effects" of the remarkable conservation success of the past few decades. Unraveling the patterns of parasite infections in both gorilla populations, evaluating host exposure to infective parasite stages, and studying susceptibility to infection and its consequences on host health will be an important next step for the continued success and survival of this and other endangered animal species with small, isolated populations.

An investigation carried out by the astrophysicists of the Instituto de Astrofísica de Canarias (IAC) ?ofia Chrobáková, a doctoral student at the IAC and the University of La Laguna (ULL), and Martín López Corredoira, questions one of the most interesting findings about the dynamics of the Milky Way in recent years: the precession, or the wobble in the axis of rotation of the disc warp is incorrect. The results have just been published in The Astrophysical Journal.

The Milky Way is a spiral galaxy, which means that it is composed, among other components, of a disc of stars, gas and dust, in which the spiral arms are contained. At first, it was thought that the disc was completely flat, but for some decades now it is known that the outermost part of the disc is distorted into what is called a "warp": in one direction it is twisted upwards, and in the opposite direction downwards. The stars, the gas, and the dust are all warped, and so are not in the same plane as the extended inner part of the disc, and an axis perpendicular to the planes of the warp defines their rotation.

In 2020, an investigation announced the detection of the precession of the warp of the Milky Way disc, which means that the deformation in this outer region is not static, but that just like a spinning top the orientation of its axis is itself rotating with time. Furthermore, these researchers found that it was quicker than the theories predicted, a cycle every 600-700 million years, some three times the time it takes the Sun to travel once round the centre of the Galaxy.

Precession is not a phenomenon which occurs only in galaxies, it also happens to our planet. As well as its annual revolution around the Sun, and its rotation period of 24 hours, the axis of the Earth precesses, which implies that the celestial pole is not always close to the present pole star, but that (as an example) 14,000 years ago it was close to the star Vega.

Now, a new study by ?ofia Chrobáková and Martín López Corredoira has taken into account the variation of the amplitude of the warp with the ages of the stars. The study concludes that, using the warp of the old stars whose velocities have been measured, it is possible that the precession can disappear, or at least become slower than what is presently believed. To arrive at this result the researchers have used data from the Gaia Mission of the European Space Agency (ESA), analysing the positions and velocities of hundreds of millions of stars in the outer disc.

"In previous studies it had not been noticed", explains ?ofia Chrobáková, a predoctoral researcher at the IAC and the first author of the article, "that the stars which are a few tens of millions of years old, such as the Cepheids, have a much larger warp than that of the stars visible with the Gaia mission, which are thousands of millions of years old".

"This does not necessarily mean that the warp does not precess at all, it could do so, but much more slowly, and we are probably unable to measure this motion until we obtain better data", concludes Martín López Corredoira, and IAC researcher and co-author of the article.