Culture

Our brains are wired to protect us from threats. For social animals like humans, threats often come from other members of our own species when there is conflict over food, mates, or territory. Animals with a strong sense of territory will attack anyone who enters their territory, but will flee if caught in the territory of another individual. In such animals, the decision to stand their ground and attack or to run away and escape depends on where the animal is. How is the decision between these two types of defensive responses made? How does our sense of territory drive our instinctive behaviour?

Previous studies from the Gross group at the site of the European Molecular Biology Laboratory in Rome have revealed the crucial function of a specific brain region, the ventromedial hypothalamus (VMH), in social fear. The VMH is a central node in the brain that receives sensory inputs from the amygdala - a region involved in organising sensory information related to emotional behaviour - and sends outputs to motor areas of the brainstem. This position midway between sensory inputs and motor outputs makes the VMH an ideal subject to understand how threats drive behaviour.

To investigate the possibility that the VMH is involved in the decision between attacking and escaping a social threat, scientists in the Gross group measured the activation of neurons while the mice were exposed to a more aggressive mouse. When the mice were in this situation, activity of a large class of neurons increased proportionally with the threat intensity, confirming that the VMH may encode an internal state of threat that is necessary to trigger defensive responses.

Unexpectedly, the scientists also observed activation of the same neurons when the animal returned to explore the place where it had been threatened previously, even though there was no longer any threat present. And, surprisingly, a second set of neurons now became active when the animal returned (via a corridor) to its home cage. Under these circumstances, the researchers could predict precisely where the animal was located - threat cage or home cage - by looking at the firing of neurons in the VMH. This demonstrates that the VMH encodes spatial context - a function that has never before been attributed to the hypothalamus.

Finally, the researchers showed that exposure to a more aggressive mouse dramatically increased the ability of the VMH to promote flight. When the VMH was artificially activated after such a situation, the animal rapidly ran away from a threat, but not when the VMH was activated before this situation. This shows that social experience can change the VMH. The researchers are currently trying to understand what mechanisms might be involved in this transformation, which allows the neural networks in the VMH to be rewired in response to experience - a process known as neural plasticity.

"This finding has important implications for the field, because previous work had argued that the VMH is hardwired to respond to threats," says group leader Cornelius Gross. "Our view holds that the VMH is dedicated to controlling both attack and flight, and that this choice is driven by its encoding of social space. When an animal is in its own territory it favours attack, but when it is in the territory of another animal it favours flight."

"These results can contribute to understanding how emotions like fear and aggression are regulated, especially in the context of territory," says Piotr Krzywkowski, who conducted the research as a PhD student in the Gross group and is now Senior Data Scientist at the company IQVIA. The results also suggest a novel role of the hypothalamus in behaviour. Rather than being viewed as an innate behavioural response region, the hypothalamus should be seen as a region that integrates present and past sensory and contextual information, processing the level of threat and adapting survival behaviours to a changing environment.

The fur of the platypus - an Australian species threatened with extinction - glows green under ultraviolet light, a new study finds. This is the first observation of biofluorescence in an egg-laying mammal (monotreme), suggesting this extraordinary trait may not be as rare as previously thought.

The research article "Biofluorescence in the platypus (Ornithorhynchus anatinus)" was published in De Gruyter's international journal Mammalia.

Two mammals - the opossum and the flying squirrel - are already known to have fur that biofluoresces under under ultraviolet (UV) light.

One of the paper's authors discovered pink biofluorescence in flying squirrels by accident while conducting a night survey for lichens, a finding reported in an earlier paper. While confirming this field observation with preserved museum specimens, the researchers decided to examine the platypuses in the next drawer along too.

They studied three museum platypus specimens: a female and a male from the Field Museum of Natural History in Chicago and another male specimen from the University of Nebraska State Museum.

In visible light, the fur of all three platypus specimens was uniformly brown. But under UV light they appeared green or cyan. The fur of the platypus absorbs UV (wavelengths of 200-400 nanometers) and re-emits visible light (of 500-600 nanometers), making it fluoresce.

Like the marsupial opossum and the placental flying squirrel, platypuses are most active during the night and at dawn and dusk. It may be that these mammals - and possibly others - developed biofluorescence to adapt to low light conditions. The researchers suggest this may be a way for platypuses to see and interact with each other in the dark.

The researchers would now like to work with an Australian team to observe biofluorescence in wild animals. And with colleagues at Northland College and Colorado State University, they are working on a project to further explore the phenomenon across the mammalian family tree.

"It was a mix of serendipity and curiosity that led us to shine a UV light on the platypuses at the Field Museum," said lead author Professor Paula Spaeth Anich, Associate Professor of Biology and Natural Resources at Northland College. "But we were also interested in seeing how deep in the mammalian tree the trait of biofluorescent fur went. It's thought that monotremes branched off the marsupial-placental lineage more than 150 million years ago. So, it was intriguing to see that animals that were such distant relatives also had biofluorescent fur."

600,000 Danes take medicine containing statins. Statins lower the cholesterol level and thus helps prevent cardiovascular disease and blood clots. But there is a different side to the coin.

Treatment with statins may also have negative side effects, some of which are so severe that people suffering from elevated cholesterol choose to stop treatment. One of the main side effects is muscle pain, also called myalgia, which may lead to reduced quality of life, pain and inactivity due to the pain.

Statin inhibits the production of cholesterol in the cell, but it also inhibits an important element in the energy production in the cells' mitochondria. Mitochondria are small, energy-producing organelles found in almost all cells in the body. Statins are suspected of lowering the energy level in the cells, thus causing myalgia in muscle cells.

The researchers therefore wished to determine whether statins also inhibited the energy production in blood cell mitochondria. And research from the Center for Healthy Aging at the Faculty of Health and Medical Sciences now shows that statins do not have the expected effect.

'We can see that long-term treatment with statins at the recommended dose increases the blood cells' ability to produce energy. These are surprising results. We had expected statins to behave the same way that they do in muscle cells, but in fact they do the exact opposite here', says Executive Director and Professor at the Center for Healthy Aging Lene Juel Rasmussen.

Statins Do Both Good and Bad

Even though the surprising results challenge the theory that statins lower the energy level, this does not necessarily mean that statins do not have adverse effects on some organs.

Because the results say nothing about whether the statins are responsible for affecting the energy level or it is the body that does that to compensate for the change caused by the statins.

'Statins are quite mysterious, as they can have both positive and negative consequences depending on the part of the body', says Lene Juel Rasmussen.

'Our results show an increase in the energy level in the blood cells, but whether that is good or bad, we cannot say. It can either mean that the statins improve the blood cells' ability to produce energy, which would be a good thing, or that the statins do damage and that the body consequently raises the energy level to mend that damage', she explains.

Different Effects on Different Parts of the Body

Even though the mechanism behind statins' effect on the blood remains unknown, the new results provide brand new insight into the effect of statins: Contrary to expectation, statins behave differently in different parts of the body.

'Previous studies suggest that statins have a potentially beneficial effect on some forms of cancer and possibly also on some forms of dementia. If we are able to produce new knowledge on the effect of statins on various parts of the body, we can use this knowledge to design drugs based on the beneficial effects. If statins have a positive effect on the brain, for example, we can focus on using them in the design of drugs for dementia', Lene Juel Rasmussen explains.

UNIVERSITY PARK, Pa. -- Your bag of mulch may not be what you think it is. In a new study, researchers at Penn State found that some bags labeled as "cypress" contain only 50% cypress, while other bags contained no cypress at all.

"Many mulch products claim to be composed of cypress," said researcher Judd Michael, Nationwide Insurance Professor of Ag Safety and Health in the College of Agricultural Sciences. "But some of the largest mulch manufacturers have been accused of intentionally misleading consumers about the species mix, and it is difficult if not impossible for consumers to know whether the product is, indeed, the species listed on the packaging."

In response to complaints about misleading packaging and fraudulent behavior by these companies, Michael and his colleagues conducted an investigation and devised a process to determine the wood species included in bags of mulch and their percentages.

According to Michael, cypress wood is generally considered highly resistant to decay, making it a popular and desired species for landscaping mulch. The research is important because homeowners and professionals apply millions of bags of mulch sold at retail, with estimated U.S. sales of $1 billion dollars annually. There are many large, national mulch brands, and the majority of mulch sold at retail is packaged in 2-cubic-foot bags.

Cypress is promoted by the mulch industry as being superior to other wood species, noted researcher Charles Ray, associate professor of ecosystem science and management. Cypress is more expensive to procure than other species, such as southern pines, he added, so manufacturers may have an economic incentive to replace some percentage of the mulch mix with cheaper, more abundant species.

"Cypress is sold at a premium due to its natural color, rot resistance and resistance to insect infestation," Ray said. "If mulch producers are including at least some non-cypress species in all their products, then this deceptive practice would result in greater profits while harming the consumer. Consumers believe they are receiving a superior wood species but don't get the protection and benefits if the product contains significant volumes of pine or other inferior species."

To assess the situation, the researchers initially tested 10 bags of a nationally distributed, branded cypress mulch product, obtained from six different states. They identified the wood species by low-power microscopic analysis in the College of Agricultural Science's Wood Anatomy Lab. Examination of the largest wood pieces suggested that all bags contained at least some non-cypress.

Next, the researchers developed and utilized a new method to sort the mulch by particle size and estimate species mix by weight. The testing procedure consisted of sifting the entire contents of a bag through a series of graduated screens and then identifying and weighing the wood pieces of similar size. With that information, using a mathematical formula, they were able to estimate the ratio of wood species in a bag.

Using the novel testing procedure, in findings published in the current issue of Wood and Fiber Science, the researchers determined the following: One of the bags, purchased in Austin, Texas, contained roughly 50% cypress, with the remainder of the content being lower-valued pine. A bag purchased in Laredo, Texas, contained no cypress, despite being labeled as cypress mulch. The remaining eight bags, researchers estimated, contained cypress percentages ranging from 30% to 60%.

The research results, Michael pointed out, show that regulators charged with protecting environmental or consumer interests need assistance from the wood-science community.

Adequately protecting the interests of consumers who purchase bio-based products, while assisting regulators and ensuring fair competition, is an important service that should be provided by a land-grant university, said Michael.

"The implication of these findings for the industry is that mulch manufacturers should become much better at process management, quality control and perhaps procurement to avoid practices that draw the ire of regulators," Ray said. "Mulch manufacturers need to more accurately meet legal requirements for species as promoted on packaging."

Philadelphia, October 29, 2020--Using sophisticated 3D genomic mapping and integrating with public data resulting from genome-wide association studies (GWAS), researchers at Children's Hospital of Philadelphia (CHOP) have found significant genetic correlations between inflammatory bowel disease (IBD) and stress and depression. The researchers went on to implicate new genes involved in IBD risk that are enriched in both derived hypothalamic neurons, from a part of the brain that has a vital role in controlling stress and depression, and organoids derived from colon cells, a region more commonly studied in the context of IBD.

The findings were published in Cellular and Molecular Gastroenterology and Hepatology.

"Our results implicate a role for the hypothalamus in the genetic susceptibility to IBD," said senior author Struan Grant, PhD, a director of the Center for Spatial and Functional Genomics at CHOP and the Daniel B. Burke Endowed Chair for Diabetes Research. "Epidemiological data has previously shown overlap between IBD and stress and depression, and now we have generated genomics data to support that association. Our results suggest that the hypothalamus warrants further study in the context of IBD pathogenesis."

IBD, which includes both Crohn's disease (CD) and ulcerative colitis (UC), is principally an immune-mediated condition characterized by dysregulated inflammation of the gastrointestinal tract. The disease course ranges from chronically active to intermittent or rare flares. Multiple genetic and environmental factors are known to contribute to the pathogenesis of IBD, including more than 230 loci for the disease that have been reported through GWAS analyses. Many of the genes residing at these loci have been implicated in pathways related to the immune system and the microbiome.

However, there is also increasing evidence for a clinical association of IBD with stress and depression. Given the role of the hypothalamus in stress responses and in the pathogenesis of depression, the researchers decided to explore the genetic role of the hypothalamus in IBD.

To begin, the researchers performed genetic correlation analyses between IBD and depression to assess the degree of genetic commonality between the two conditions, using publicly available data. The research team used depression as a proxy for stress because there are a limited number of GWAS efforts focused on a consistent definition of stress, while in contrast, the genetics of depression has been relatively well-studied, resulting in a large, relatively uniform body of work.

Analyzing eleven autoimmune diseases for correlations with depression, the researchers found IBD was the most statistically significantly trait positively correlated with depression, though asthma and multiple sclerosis were noted as being highly correlated as well.

The research team then performed further analyses in order to validate the correlation between IBD and depression. First, they measured the enrichment of IBD-associated genetic variants in the 3D genomic patterns within hypothalamic-like neurons (HNs) and colonoids from rectal biopsies and found a highly significant four-fold increase in HNs and a seven-fold increase in the better-known colonoid setting. The researchers then used a sophisticated "variant-to-gene mapping" approach devised at CHOP to determine which genes are implicated in the pathogenesis of IBD at these enriched signals. Then, assessing those implicated genes, the researchers looked for pathways potentially influenced by IBD-associated genetic variants.

Through this variant-to-gene mapping effort, the researchers implicated 25 genes in HNs for conferring risk for IBD. Eleven of those genes have known functions in the brain, in particular CREM, CNTF and RHOA, which are genes that encode key regulators of stress. Seven of those genes were also implicated in the colonoids. In terms of pathways, the researchers observed an overall enrichment for hormonal signaling pathways, in addition to the expected enrichment in immune and microbiome signaling pathways.

"We propose that some IBD-associated variants alter the hypothalamus-pituitary-adrenal axis and stress responses, which could in turn play a role in predisposing patients to this disease and exacerbating its presentation," Grant said. "Future studies are warranted to refine our understanding of the role of the hypothalamus in IBD onset."

The gut is an unusually noisy place, where hundreds of species of bacteria live alongside whatever microbes happen to have hitched a ride in on your lunch. Scientists have long suspected that the gut's immune system, in the face of so many stimuli, takes an uncharacteristically blunt approach to population control and protection from foreign invaders--churning out non-specific antibodies with broad mandates to mow the gut's entire microbial lawn without prejudice.

But now, new research published in Nature suggests that the gut's local immune system can be quite precise, creating antibodies that appear to home in on specific microbiota.

"It was thought that the gut immune system worked sort of like a general-purpose antibiotic, controlling every bug and pathogen," says Gabriel D. Victora, an immunologist and head of the Laboratory of Lymphocyte Dynamics . "But our new findings tell us that there might be a bit more specificity to this targeting."

The research suggests that our immune system may play an active part in shaping the composition of our microbiomes, which are tightly linked to health and disease. "A better understanding of this process could one day lead to major implications for conditions where the microbiome is knocked out of balance," says Daniel Mucida, head of the Laboratory of Mucosal Immunology.

Specificity in the mouse gut

When faced with a pathogen, the immune system's B cells enter sites called germinal centers where they "learn" to produce specific antibodies until one B cell emerges, finely-tuned to recognize its target with high efficiency. Dubbed a winner clone, this B cell replicates to generate a mob of cells that produce potent antibodies.

Victora, Mucida, and colleagues set out to study how these B cells interact with the melting pot of bacterial species in the gut--an overabundance of potential targets. Looking at the germinal centers that form in mice intestines, they found that about 1 in 10 of these gut-associated germinal centers had clear winner clones. They then homed in on the winning B cells and found that their antibodies were indeed designed to bind with ever increasing potency to specific species of bacteria living in the gut.

The findings show that even in the gut, where millions of microbes wave their thousands of different antigens and vie for the immune system's attention, germinal centers manage to select specific, consistent winners.

"We can now investigate the winners and look at evolution in germinal centers as an ecological issue involving many different species, as we try to figure out the rules underlying selection in these complex environments," Victora says. "This opens up a whole new area of inquiry."

ITHACA, N.Y. - In the dark of night, ogre-faced spiders with dominating big eyes dangle from a silk frame to cast a web and capture their ground prey. But these spiders also can capture insects flying behind them with precision, and Cornell University scientists have now confirmed how.

In a new study, researchers confirmed these spiders use metatarsal sensitivity - sensors at the tip of the leg - to detect sound cues of various frequencies from up to 6 feet away. These cues trigger a split-second, ninja-like backflip to strike unsuspecting airborne insects, bag them in a web net, and then dine.

"These spiders have finely tuned sensory systems and a fascinating hunting strategy," said lead author Jay Stafstrom, a postdoctoral researcher in the laboratory of Ronald Hoy, professor of neurobiology and behavior at Cornell. "These spiders have massive eyes so they can see at night and catch things off the ground, but they can 'hear' quite well, detecting sounds through their metatarsal organ, as these spiders excel at catching things from the air."

Net-casting, ogre-faced spiders (Deinopis spinosa), are nocturnal creatures found mostly in the southeastern United States. While people are familiar with spiders that create orb webs, this species makes personal, fuzzy webs - like small nets - and uses the strong, sticky silk like a baseball glove, according to Hoy.

Spiders don't have ears, but they can sense a wide range of sounds thanks to the metatarsal organ located near the tip of their legs.

Stafstrom collected these spiders and brought them to Gil Menda, a postdoctoral researcher in Hoy's lab, who recorded neural activity from both their brains and their legs. He played pure tone frequencies to the spiders and noted the spider's neurons became excited for difference tones.

Stafstrom examined frequencies that ranged from 150 Hz (the flute-like sound of blowing over a glass soda bottle) to 750 Hz (the high-pitched drone of a local television nighttime sign-off) to 10 Khz, a piercing, high-pitched sound.

"While the spiders were sensitive to low-frequency tones, as expected, we didn't really expect to see net-casting spiders sensitive to a wide range of frequencies - all the way to 10 kilohertz," he said.

They look like microscopic bottle brushes: Polymers with a backbone and tufts of side arms. This molecular design gives them unusual abilities: For example, they can bind active agents and release them again when the temperature changes. With the help of neutrons, a research team from the Technical University of Munich (TUM) has now succeeded to unveil the changes in the internal structure in course of the process.

"The structure of the bottle-brush polymers, which are only nanometers in size, cannot be investigated using classical optical methods: It can be seen that an aqueous solution containing these polymers becomes turbid at a certain temperature. But why this is the case, and how the backbone and the side arms stretch out into in the water or contract, has not yet been clarified," reports Prof. Christine Papadakis.

There is a simple reason why scientists would like to know more about the inner life of bottle-brush polymers: The fluffy molecules, which consist of different polymer chains and abruptly change their solubility in water at a certain temperature, are promising candidates for a variety of applications.

For example, they could be used as catalysts to accelerate chemical reactions, as molecular switches to open or close tiny valves, or as transport media for medical drugs - the molecular brushes could thus bring pharmaceuticals to a center of inflammation and, because the temperature is elevated there, release them directly at the site of action.

However, the basic prerequisite for using the brush molecules is that their behavior can be programmed: Theoretically, chemists can use a combination of water-soluble and water-insoluble building blocks to determine precisely at what temperature the polymers clump together and the liquid in which they were just dissolved becomes cloudy. "In practice, however, you have to know exactly how and under what conditions the structure of the polymers changes if you want to design smart brush molecules," explains Papadakis.

Neutrons reveal their molecular inner life

Together with her team in the Soft Matter Physics Group at the Technical University of Munich, she has now been able to visualize for the first time the changes that bottle-brush polymers with arms made of two different types of building blocks undergo when the temperature reaches the cloud point.

The scientists used neutron radiation from the Research Neutron Source Heinz Maier-Leibnitz (FRM II) on the campus Garching in a special instrument for small angle neutron scattering, which is operated by the Forschungszentrum Jülich

This method is particularly well suited for the investigation because neutrons are electrically neutral and therefore penetrate matter easily. There they are scattered by the atomic nuclei, which results in detailed information about the brush molecules. In combination with modern cryo electron microscopy, a detailed understanding of these molecules could be obtained.

When brushes clump together

The thermoresponsive brush molecules studied by Papadakis' team were synthesized by chemists from the National Hellenic Research Foundation in Greece and the Technische Universität Dresden, respectively.

In the first step, the samples were dissolved in water, then gradually heated up to the cloud point and irradiated with neutrons. A detector monitored the scattered radiation. From the scattering signal, the researchers were able to deduce the structural changes.

Depending on the structure of the polymers, water molecules split-off already before the cloud point was reached. At the cloud point itself, the molecular structure of the polymers collapsed. What remained were water-insoluble polymer coils, which formed loose or compact clusters depending on the residual water content.

"The results will help to develop bottle-brush polymers suitable for practical use," the physicist is convinced. "If you know exactly how polymers change at the cloud point, you can optimize their chemical structure for different applications."

In 2017 the term 'populism' made 'Word of the Year' according to The Cambridge Dictionary for its ubiquitous use across media headlines, in political speeches, campaigns, as well as across numerous academic publications and conferences.

According to new analysis from political scientists at the University of Bath however, the pervasive use of the term - also termed 'populist hype' - has had serious consequences in helping to legitimise certain kinds of politics, most notably the far right.

Writing in the journal Politics, the researchers from the Department of Politics, Languages & International Studies at Bath, analysed coverage from The Guardian's 'new populism' six-month series which ran from November 2018 and was designed to explore the term from different vantages.

In their critique they argue that 'populism' has fast-become a catch-all term attributed to an array of different phenomena and political standpoints - from a jazz musician and the film Sweet Home Alabama, to nationalism, protectionism of an economy and racism. The replacement of more accurate descriptions with 'populism', as well as the lack of care in it use, has muddied the waters as to what exactly we are talking about.

Most commonly though, 'populism' is attributed to far-right politics and this brings its own set of problems. The researchers warn that 'populism' has too often been reported on as a response to pent-up demands from 'the people', while ignoring the role of the media and politicians in its growth in popularity, both as a term and type of politics. Beyond the lack of clarity, it has also created or at least exaggerated links between 'the people' and the far right in particular, lending elitist and minoritarian politics a veneer of democratic legitimacy.

Focusing on The Guardian's new populism series, they suggest this was a missed opportunity to provide clarity on a term and type of politics which have shaped our current political age, but not always as we think it has. Highlighting one article from that series in particular - headline: 'Why is populism suddenly all the rage?'; sub-header: 'In 1998, about 300 Guardian articles mentioned populism. In 2016, 2,000 did. What happened? -they suggest the piece failed to acknowledge that to a large extent the massive upsurge in use was also a result of editorial choices.

Dr Aurelien Mondon of the University of Bath's Department of Politics, Languages & International Studies explains: "While Trump, Orban or Le Pen can indeed make use of populist discourse by pitting a constructed version of a 'people' against an 'elite', this is only a small part of their politics, which draw more from other larger ideologies and ideas such as ultra-conservatism, racism, or even fascism. While populism can help us understand the discursive nature of such politics, it does little on its own to explain their broader meaning and potential consequences."

Co-author Katy Brown also of the Department of Politics, Languages & International Studies, says: "This is by no means a problem unique to The Guardian, and there were many excellent contributions to its 'the new populism' series, but the problems we identify illustrate the importance of critical and careful use of terminology.

"The simplification and trivialisation of the term 'populist' has blurred meanings between phenomena such as nativism, nationalism, protectionism and racism which has helped to legitimate them by avoiding deeper scrutiny of so-called 'populist' policies."

Their critique is not reserved to the media. In their analysis they also highlight a huge upswing in the use of the term 'populism' throughout academic literature, some of it, they argue, without sufficient critical reflection or care taken over how it has been applied.

Dr Mondon adds: "Academics have a real role to play in helping people make sense of society and politics, and the work done on populism is key to this. However, it is essential that we reflect upon the impact our work has and how it is interpreted in wider circles. Hopefully, our article makes one such contribution."

Washington, DC--New work led by Carnegie's Matt Clement reveals the likely original locations of Saturn and Jupiter. These findings refine our understanding of the forces that determined our Solar System's unusual architecture, including the ejection of an additional planet between Saturn and Uranus, ensuring that only small, rocky planets, like Earth, formed inward of Jupiter.

In its youth, our Sun was surrounded by a rotating disk of gas and dust from which the planets were born. The orbits of early formed planets were thought to be initially close-packed and circular, but gravitational interactions between the larger objects perturbed the arrangement and caused the baby giant planets to rapidly reshuffle, creating the configuration we see today.

"We now know that there are thousands of planetary systems in our Milky Way galaxy alone," Clement said. "But it turns out that the arrangement of planets in our own Solar System is highly unusual, so we are using models to reverse engineer and replicate its formative processes. This is a bit like trying to figure out what happened in a car crash after the fact--how fast were the cars going, in what directions, and so on."

Clement and his co-authors--Carnegie's John Chambers, Sean Raymond of the University of Bordeaux, Nathan Kaib of University of Oklahoma, Rogerio Deienno of the Southwest Research Institute, and André Izidoro of Rice University--conducted 6,000 simulations of our Solar System's evolution, revealing an unexpected detail about Jupiter and Saturn's original relationship.

Jupiter in its infancy was thought to orbit the Sun three times for every two orbits that Saturn completed. But this arrangement is not able to satisfactorily explain the configuration of the giant planets that we see today. The team's models showed that a ratio of two Jupiter orbits to one Saturnian orbit more consistently produced results that look like our familiar planetary architecture.

"This indicates that while our Solar System is a bit of an oddball, it wasn't always the case," explained Clement, who is presenting the team's work at the American Astronomical Society's Division for Planetary Sciences virtual meeting today. "What's more, now that we've established the effectiveness of this model, we can use it to help us look at the formation of the terrestrial planets, including our own, and to perhaps inform our ability to look for similar systems elsewhere that could have the potential to host life."

The model also showed that the positions of Uranus and Neptune were shaped by the mass of the Kuiper belt--an icy region on the Solar System's edges composed of dwarf planets and planetoids of which Pluto is the largest member--and by an ice giant planet that was kicked out in the Solar System's infancy.

COLUMBUS, Ohio - As COVID-19 cases begin climbing again in the United States, the possibility arises of a grim moral dilemma: Which patients should be prioritized if medical resources are scarce?

Researchers from the United States and China asked more than 5,000 people from 11 countries how they would make one version of that ethical decision. Study participants considered 15 possible scenarios, choosing which of two COVID-19 patients should get access to a ventilator that could save their life.

The two patients they had to choose between differed on 10 characteristics, including age, gender, probability of survival and criminal history.

Results showed that people worldwide gave two characteristics the most weight when they made their decision: age and probability of survival.

Those two characteristics explained about 50 percent of their decisions, results showed. The other eight characteristics combined explained the other 50 percent.

"People seemed to want to maximize total benefits to society by choosing those who would live longest as a result of the treatment, either because of their younger age or because of overall probability of survival," said Yunhui Huang, co-author of the study and assistant professor of marketing at The Ohio State University's Fisher College of Business.

"It's a very utilitarian way of deciding."

But there were some differences in how people decided that depended on the culture of their country, the number of cases where they lived, and whether they felt personally threatened by the disease, the study showed.

Huang conducted the study with Liyin Jin and Yongheng Liang of Fudan University in Shanghai and Qiang Zhang of the Chinese University of Hong Kong in Shenzhen. The study was published online recently in the Journal of the Association for Consumer Research.

The 5,175 participants came from 11 countries that at the time of the data collection (April 8-18, 2020) covered about 49 percent of the world's population and 69 percent of confirmed COVID-19 cases. China, the United States, Brazil, the United Kingdom, Australia and South Korea were among them.

All people participated online. In the 15 scenarios, the participants were presented with two COVID-19 patients who both needed a ventilator to survive when only one was available. They were asked which patient should be given the ventilator. They then completed a survey that collected demographic information and asked how much they felt COVID-19 affected their own life.

Both patients in the scenarios were described based on 10 characteristics: age, gender, probability of survival, socioeconomic status, criminal record, the number of people who the patient has infected, family members who have also been infected, the expected number of days that this patient needs to be on the ventilators, the costs paid by public finance and nationality.

"Other than age and probability of survival, the other eight were given considerably lower weight in our sample, and their weights did not differ significantly from one another," said Huang.

Still, the findings showed that people generally preferred prioritizing people who shared their own nationality, those who had never committed a crime, and those who were likely to incur lower costs, would need fewer days on the ventilator and had infected fewer people.

The researchers found differences in the responses of people from collectivist cultures, which emphasize the needs and goals of the group, versus individualistic cultures.

In collectivist cultures like China, which emphasize respect for the elderly, there was a weaker preference for saving young versus old patients. They also prioritized people with the same nationality and those without a criminal record.

Individualistic cultures, like the United States, attached greater importance on the patient's probability of survival when deciding who got the ventilator.

There were also differences in responses depending on the attitude of the culture toward power inequalities in society. Study participants from countries like Korea, where inequality among people is more accepted, put more emphasis on criminal records in their decisions.

"Research has shown that cultures that accept a higher degree of inequality also prefer a more structured world, so it makes sense that they would not prioritize patients who disrupt that stability," Huang said.

Cultures that find inequality among people less acceptable attached even greater importance to survival probability, possibly because that attribute is not related to social class and status, she said.

Elements of the COVID-19 pandemic itself affected people's moral choices, the study found. People in areas with more COVID-19 cases were even more likely to favor the young. That is consistent with previous findings that have found that perceived loss of control, which is likely common among people during a pandemic, is linked to more utility-based moral preferences.

But people who said they felt more personally impacted by COVID-19 made a different calculation in their decisions: They put less emphasis on survival probability when deciding who should get the ventilator.

"One possible explanation is that people who feel personally threatened by COVID-19 may put more importance on their own personal characteristics when thinking about who should get a ventilator at the expense of survival probability," Huang said.

These findings about how the pandemic itself affected people's choices have important implications.

"During the course of the pandemic, people's moral choices might change as they feel more or less threatened by what is going on around them," Huang said.

The research is not intended to guide decision-making by doctors or policymakers, Huang said. But it is important to know how the public feels about these ethical issues.

For example, the findings showed that factors like criminal records and nationality, which presumably should not influence treatment decisions, sometimes affected people's choices.

"Doctors and policymakers need to know how the public thinks about these issues as they communicate about their policies involving these difficult decisions," Huang said.

LAWRENCE -- How likely you are to trust a self-driving car or advice from Siri?

A University of Kansas interdisciplinary team led by relationship psychologist Omri Gillath has published a new paper in the journal Computers in Human Behavior showing people's trust in artificial intelligence (AI) is tied to their relationship or attachment style.

The research indicates for the first time that people who are anxious about their relationships with humans tend to have less trust in AI as well. Importantly, the research also suggests trust in artificial intelligence can be increased by reminding people of their secure relationships with other humans.

Grand View Research estimated the global artificial-intelligence market at $39.9 billion in 2019, projected to expand at a compound annual growth rate of 42.2% from 2020 to 2027. However, lack of trust remains a key obstacle to adopting new artificial intelligence technologies.

The new research by Gillath and colleagues suggests new ways to boost trust in artificial intelligence.

In three studies, attachment style, thought to play a central role in romantic and parent-child relationships, was shown also to affect people's trust in artificial intelligence. Some of the research's key findings:

People's attachment anxiety predicts less trust in artificial intelligence.

Enhancing attachment anxiety reduced trust in artificial intelligence.

Conversely, enhancing attachment security increases trust in artificial intelligence.

These effects are unique to attachment security and were not found with exposure to positive affect cues.

"Most research on trust in artificial intelligence focuses on cognitive ways to boost trust. Here we took a different approach by focusing on a 'relational affective' route to boost trust, seeing AI as a partner or a team member rather than a device," said Gillath, professor of psychology at KU.

"Finding associations between one's attachment style -- an individual difference representing the way people feel, think and behave in close relationships -- and her trust in AI paves the way to new understandings and potentially new interventions to induce trust."

The research team includes investigators from a wide array of disciplines, including psychology, engineering, business and medicine. This interdisciplinary approach provides a new perspective on artificial intelligence, trust and associations with relational and affective factors.

"The findings show you can predict and increase people's trust levels in non-humans based on their early relationships with humans," Gillath said. "This has the potential to improve adoption of new technologies and the integration of AI in the workplace."

We may wish some memories could last a lifetime, but many physical and emotional factors can negatively impact our ability to retain information throughout life.

A new study published in the journal Psychological Science found that people who feel enthusiastic and cheerful--what psychologists call "positive affect"--are less likely to experience memory decline as they age. This result adds to a growing body of research on positive affect's role in healthy aging.

A team of researchers analyzed data from 991 middle-aged and older U.S. adults who participated in a national study conducted at three time periods: between 1995 and 1996, 2004 and 2006, and 2013 and 2014.

In each assessment, participants reported on a range of positive emotions they had experienced during the past 30 days. In the final two assessments, participants also completed tests of memory performance. These tests consisted of recalling words immediately after their presentation and again 15 minutes later.

The researchers examined the association between positive affect and memory decline, accounting for age, gender, education, depression, negative affect, and extraversion.

"Our findings showed that memory declined with age," said Claudia Haase, an associate professor at Northwestern University and senior author on the paper. "However, individuals with higher levels of positive affect had a less steep memory decline over the course of almost a decade," added Emily Hittner, a PhD graduate of Northwestern University and the paper's lead author.

Areas of future research might address the pathways that could connect positive affect and memory, such as physical health or social relationships.

Zooplankton can grow faster and produce more offspring when exposed to a substance that affects human happiness.

"These substances are antidepressants, so-called 'happy pills,' that are often used in the treatment of smoking cessation and depression. Our wastewater is one pathway for the substances to end up in nature," says Professor Sigurd Einum at the Norwegian University of Science and Technology's (NTNU) Centre for Biodiversity Dynamics (CBD) in the Department of Biology.

A research group at NTNU is studying how different substances affect animals. Einum and Professor Veerle Jaspers from the same department are leading the group. PhD candidate Semona Issa is the first author of their recently published article. She is also affiliated with the Centre for Biodiversity Dynamics.

The researchers have investigated how changes in the level of the drug dopamine affect daphnia, a small genus of water fleas. Water fleas are small zooplankton that are found in large numbers in many kinds of water. They are important for controlling the growth of algae and bacteria, and also as prey for a number of species.

There are over 400 species of water fleas. The group studied the Daphnia magna species, which is common in freshwater in large parts of the world.

"Dopamine is a neurotransmitter that is produced naturally in the body, and which raises or lowers the activity in various nerve cells. Among other things, dopamine can trigger a feeling of happiness," says Einum.

The release of drug residues or substances that affect dopamine levels in the body occur all the time, especially in wastewater. In Norway alone, doctors prescribe more than 100 million doses of antidepressants a year.

The researchers measured the effect of higher concentrations of both dopamine and the drug bupropion in water fleas. Bupropion is used to reduce depression and to help people quit smoking. The drug affects the concentration of dopamine in human cells.

"We're finding that this substance also affects various characteristics of water fleas, like growth rate and age at sexual maturation," says Einum.

The effect was most evident when little food was to be had in the surroundings.

Apparently, bupropion causes water fleas to grow and produce offspring faster.

"A faster life cycle is usually a sign of stress," says Issa. "But we don't know if this is a short-term effect."

"Water fleas that are exposed to higher dopamine levels could undergo behavioural changes that make them more vulnerable to being eaten, for example, but we haven't tested that yet," Einum says.

"Faster growth due to increased dopamine levels also reduces the amount of energy that can be used for immune function. It could make the water fleas more vulnerable to parasites and diseases," says Issa.

We don't yet know for sure that higher dopamine levels are any advantage over time, nor do we know why water fleas do not naturally produce higher levels of dopamine.

It could be that increased production of dopamine can also increase so-called oxidative stress. This can cause harmful substances to accumulate when the cell releases energy. Oxidation of dopamine occurs in the nerve cells where dopamine is produced. Then reactive oxygen compounds are formed that damage the cells.

As the country enters the final days of a marathon and polarizing election season, politicians' faces are everywhere. And that trend is not likely going anywhere, especially in the realm of social media.

A University of Georgia researcher used computer vision to analyze thousands of images from over 100 Instagram accounts of United States politicians and discovered posts that showed politicians' faces in nonpolitical settings increased audience engagement over traditional posts such as politicians in professional or political settings.

"Faces are a very important vehicle to extracting emotions," said Yilang Peng, an assistant professor in the UGA College of Family and Consumer Sciences. "In general, people are paying attention to posts that feature faces, and especially faces of people they recognize."

Using computer vision methods, Peng analyzed over 59,000 images published on Instagram of 159 U.S. politicians sampled in fall 2018, including presidential candidates, governors, senators and Cabinet members.

"Computer vision is an emerging field that looks at how we can train computers to imitate human vision, like detecting objects," Peng said.

The technique has been applied to facial recognition software, self-driving cars and even in medical imaging, whereby a computer can extract and identify common features from thousands or millions of images.

Using this method, visual messages can be described both in terms of content as well as aesthetic appeal, including brightness, blur, color, composition and even facial expressions, Peng said.

Peng identified four broad categories to classify the setting of the politicians' images:

professional/political setting, such as press conferences, offices, rallies and protests;

text/illustration, such as graphics and test-based messages;

personal setting, showing individuals in private or nonpolitical settings such as restaurants, homes or gyms;

and architecture/landscape, featuring views of buildings or landscapes, often without people.

Roughly 60 percent of the posts analyzed fell into the professional/political setting category.

"These kinds of posts are generally not that successful in terms of attracting comments or likes," Peng said.

On average, images in the personal setting category received about 20 percent more likes on Instagram compared to the professional setting and text/illustration categories.

Images with only the politician's face, as opposed to the politician with other people or images without faces, also attracted more likes and comments.

Personalization strategies, such as posts showing the politician at the local soccer field or at home with a pet, seemed to help drive interaction, Peng said.

"In summary, faces drove audience engagement," Peng said.

Peng said computer vision can have a variety of applications for future political campaigns, including analysis of political videos on social media and other media effects beyond audience engagement.

Peng also published a study in 2018 that used computer vision to detect media bias in portrayals of President Donald Trump and Hillary Clinton.

"In the future you can look at how do these visual materials actually change people's perception of the candidate," Peng said.

Peng's study, "What makes politicians' Instagram posts popular? Analyzing social media strategies of candidates and office holders with computer vision," was published by The International Journal of Press/Politics.