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To understand our brains, scientists need to know their components. This theme underlies a growing effort in neuroscience to define the different building blocks of the brain -- its cells.

With the mouse's 80 million neurons and our 86 billion, sorting through those delicate, microscopic building blocks is no small feat. A new study from the Allen Institute for Brain Science, which was published today in the journal Nature Neuroscience, describes a large profile of mouse neuron types based on two important characteristics of the cells: their 3D shape and their electrical behavior.

The study, which yielded the largest dataset of its kind from the adult laboratory mouse to date, is part of a larger effort at the Allen Institute to discover the brain's "periodic table" through large-scale explorations of brain cell types. The researchers hope a better understanding of cell types in a healthy mammalian brain will lay the foundation for uncovering the cell types that underlie human brain disorders and diseases.

If you think of the classical periodic table, chemical elements can be described and sorted in a number of ways: their mass, their chemical properties, whether they are metal or not. Neuroscientists are faced with a similar challenge. A given neuron will have many different personality traits that distinguish it from other neuron types: its shape, its behavior, the unique set of genes it switches on, its location in the brain, the other types of cells it interacts with.

How do you define a cell type?

To understand what a single cell type does, researchers need to explore all these attributes, said Hongkui Zeng, Ph.D., Executive Director of Structured Science at the Allen Institute for Brain Science, a division of the Allen Institute, and senior author on the study.

"A cell type is a group of cells that have similar functional properties to each other, but we don't understand what all those properties are," Zeng said. "We shouldn't just be looking at a single feature; we need to look at as many features of the cells as possible and ask whether they are consistent with each other."

In the study, the research team sorted through neurons from the visual processing part of the mouse brain to find a few dozen different brain cell types, carefully analyzing close to 2,000 neurons' electrical activity and their detailed 3D shape (also known as morphology) of nearly 500 of those same cells. The researchers also saw that these new cell type categories line up with categories from a complementary study published last year. In that earlier study, Allen Institute researchers used gene expression, or the list of genes that are switched on in any one cell, to sort nearly 24,000 brain cells into different types.

The fact that different features yield similar cell type groups gives the researchers confidence that they're on the right track in their categorization, said Staci Sorensen, Ph.D., a neuroscientist who leads the morphology team at the Allen Institute for Brain Science and is a lead author on the study along with Nathan Gouwens, Ph.D., and Jim Berg, Ph.D. "If we get alignment across multiple properties of a cell, then we can feel more confident that we have a biologically meaningful cell type," Sorensen said.

Why shape and activity matter

Their activity and shape also give the researchers clues about what the individual cells are doing in the larger context of neural circuits in the brain. Electrical signaling using pulses, so-called spikes or action potentials, is the near universal idiom of the way neurons communicate with each ones. Different neurons are tuned to send and receive different patterns of such spikes.

Understanding those signals helps researchers reconstruct how these neurons might connect to others in a circuit. And their shape gives a clue as well.

"A cell's shape is a proxy for how it's connected to other cells," said Gouwens, a computational neuroscientist at the Allen Institute. "We care about how cells are connected to each other because that's how they form circuits to process information."

Data for the community

The researchers hope that these publicly available data -- along with the data about brain cell types' gene expression, all of which are part of the Allen Cell Types database -- will enable deeper exploration into specific cell types in health and disease. If a research team is interested in a specific disease-related gene in the brain, for example, they can see which cell types have that gene switched on, or expressed, and then explore the shape and activity of those neurons to form new hypotheses about how the gene might act -- and what might go wrong in disease if the gene is mutated or missing.

"They can form a hypothesis as to how the gene dysfunction might change that cell type, how it might lead to specific effects," said Berg, a neuroscientist at the Allen Institute for Brain Science who leads the team that measures neurons' electrical activity. "It takes a lot of numbers to get that coverage so that people can trust the data, but I think we're finally at that phase."

An unbiased approach

To study a neuron's morphology, researchers need to first identify a single cell amidst the tangled mess of other neurons and supporting cells in the mouse brain and then inject that one cell with a special dye-containing probe to stain it in its entirety within a slice of brain. The team used mice that were engineered at the Allen Institute to carry genes that make certain neurons glow bright colors under the microscope, letting the researchers more easily pick out individual neurons. The researchers then used those same microscopic probes to read out the cells' electrical activity by studying their responses to different types of electrical input.

Because these experiments are so labor-intensive, research groups typically explore one or a handful of cell types at a time, which are often selected based on a specific question. The Allen Institute team, however, wanted to tackle the problem in a broad, unbiased fashion, studying cells under the same experimental conditions and from the same region of the brain so they can be more easily compared to each other.

"Instead of having a list of cell types already in mind and then putting the cells into those categories, we're letting the categories emerge from the data," Gouwens said. "We're trying to be fairly broad and then see what shape the data have."

PHILADELPHIA - The human immune system relies on a delicate balance of finely tuned cell types that keep germs and cancerous cells in check. In cancer and chronic infections this balance can be disrupted, resulting in immune system dysfunction or "exhaustion." An important protein called TOX, which varies in amount in different immune cell types, controls the identity of the cells that become exhausted, according to researchers in the Perelman School of Medicine at the University of Pennsylvania. With this knowledge, investigators now have a way to accurately identify immune cells that are exhausted in a tumor or site of an infection, which could allow clinicians to improve the effectiveness of patients' immune response to cancer treatments by reinvigorating exhausted T cells. This work is published this week in Nature.

"The discovery of TOX as the key regulator of exhausted T cells now allows us to envision immunotherapies that target, or engineer, TOX to reverse or prevent exhaustion and improve immunity to infections or cancer," said senior author E. John Wherry, PhD, chair of the department of Pharmacology and director of the Penn Institute of Immunology.

The T cells the team studied come in three varieties and rely on efficient and coordinated transitions between different identities. Following initial activation by specific proteins, immature T cells replicate and undergo an orchestrated program of molecular rewiring to become effector T cells (TEFF), which produce inflammatory cytokines that kill offending cancer and germ cells.

If an infection or tumor is cleared, most of the TEFF pool dies, but a subset persists. This set undergoes more rewiring and forms long-lived, self-renewing memory T cells (TMEM) capable of mounting a rapid recall response should an invader be detected a second time. However, during chronic infections or with cancer, when T cell stimulation is drawn out, this program of T cell differentiation is diverted and the cells becoming ineffective against the tumor or infection--instead, they become exhausted. But, these exhausted T cells (TEX) are not totally useless. In fact, they may keep low-level germ or tumor presence in the body in check.

In this battle, Wherry likens TEX to an infantry that performs the day in and day out work of containing minor assaults, such as long-term infection by the herpes virus. On the other end of the spectrum, TEFFs are like calling in the Navy SEALs.

"They get the job of containment done, and quickly, by whipping up a cytokine storm, but there is the collateral damage of an overactive inflammatory response," Wherry said. TEX are not strong enough to cause an increased inflammatory response, and in some cases, may strike a necessary balance between partially containing an infection or tumor without causing excessive damage to the host.

The longer TOX is expressed in a T cell the more permanent the TEX identity becomes. The level of TOX in a T cell dictates how an infection or tumor is contained by controlling the number of TEFF versus TEX cells. High and sustained induction of TOX results in the permanent existence of TEX, but the consequences of a restrained ability to fight invaders can be the persistence or progression of disease.

The team also showed that TOX shapes cell identity by making the spools on which genes are wound in the nucleus more or less available to be translated into proteins. This ability of TOX to shape the structure of a cell's genome via its epigenome also provides insight into why changing TEX into TEFF has been difficult with other therapies. Epigenetic changes help "lock" cells into their permanent identity, but these new findings may allow researchers to change that for future immunotherapies.

Most fishing communities from North Carolina to Maine are projected to face declining fishing options unless they adapt to climate change by catching different species or fishing in different areas, according to a study in the journal Nature Climate Change.

Some Maine fishing communities were at greatest risk of losing their current fishing options, according to the study by Rutgers and other scientists.

"Some communities like Portland, Maine, are on track to lose out, while others like Mattituck, New York, or Sandwich, Massachusetts, may do better as waters warm," said senior author Malin Pinsky, an associate professor in the Department of Ecology, Evolution, and Natural Resources at Rutgers University-New Brunswick. "Adapting to climate change for many communities will require fundamentally new approaches to fishing. Change has become the new normal."

Fishing has been the economic and cultural lifeblood for many coastal towns and cities along the Northeast coast, in some cases for hundreds of years, Pinsky said. But climate change is expected to have a major impact on the distribution, abundance and diversity of marine species worldwide, the study notes.

The researchers, including Kevin St. Martin, an associate professor in the Department of Geography at Rutgers-New Brunswick, studied how climate change will likely affect the fishing opportunities for 85 communities in New England and the Mid-Atlantic. They used 13 global climate models to project how ocean temperatures are likely to change, then examined ocean temperatures and types of bottom habitat to determine where important commercial fisheries species are likely to move. They also looked at whether the species caught by fishing communities are likely to become more or less abundant in the ocean regions where they typically fish.

While fish species may shift as the climate changes, fishers often have limits on where they can fish based on local ecological knowledge, vessel size or gear type, the distance to fishing areas, management or conservation measures and, in some cases, traditional fishing territories.

For 24 of 33 species studied, habitat was projected to improve in some Northeast regions and deteriorate in others by 2040 to 2050. For example, monkfish habitat was expected to expand in the Gulf of Maine but become less suitable throughout the Mid-Atlantic Bight, including waters off the New Jersey coast, according to the study.

Sixty-four of the 85 communities are projected to face increased risk (fewer fish resources due to changes in habitat) by 2050, suggesting declines in fishing options if current practices continue. Communities of small trawlers in Maine faced the most risk because of their historical dependence on species, such as Atlantic cod and witch flounder, that are expected to lose suitable habitats.

For communities, adaptation will likely require shifting where fishing vessels go to follow their target species or focusing on "winner" species versus losers, the study says.

BATON ROUGE, LOUISIANA, June 17, 2019--Getting an excellent rabbiteye blueberry harvest requires helpful pollinators--particularly native southeastern blueberry bees--although growers can bring in managed honey bees to do the job, according to Agricultural Research Service (ARS) scientists.

This is especially true for commercial rabbiteye blueberry producers in Mississippi and Louisiana. With sufficient pollinators, they have been able to increase the percentage of flowers setting fruit from 10-30 percent to 70 percent or more. A mature rabbiteye blueberry bush can produce as much as 15 pounds of berries.

Fully pollinated berries also are bigger and mature earlier than fruit from inadequately pollinated flowers. So, bee-pollinated flowers produce fruit that bring a premium in the marketplace.

"We looked at multiple species of bees to see which did the best job of pollinating rabbiteye blueberries. We tested managed honey bees, native bumble bee species, southeastern blueberry bees and carpenter bees," explained research entomologist Robert Danka with the ARS Honey Bee Breeding, Genetics, and Physiology Research Laboratory in Baton Rouge, Louisiana, who co-led the study.

Of these bees, only the southeastern blueberry bee and the honey bee significantly increased fruit set, according to Danka "And the native southeastern blueberry bee did the best job," he said.

But the only way for commercial growers to have enough southeastern blueberry bees to provide a superior level of pollination is to provide habitat on the edges of their fields that encourages their population to grow.

"What commercial growers can do is provide woodlands near the edges of their fields because that's where southeastern blueberry bees prefer to nest. They are ground-dwelling bees that like shade and leaf litter but don't like wet or soil heavy with organic material," explained research entomologist Blair Sampson with the ARS Thad Cochran Southern Horticultural Laboratory in Poplarville, Mississippi.

A small grower with 1-3 acres of blueberries can probably get by solely with the pollination of native bees, especially if they have encouraged them with attractive habitat. But a grower with fields of 25 acres and more should probably consider supplementing by bringing in honey bee colonies, Sampson pointed out.

Complicating the matter is that some southeastern blueberry bees' population vary greatly from year to year, depending on rain and other weather conditions while other populations were reliably present every year in the study.

"A farmer who sees that during the first few days of bloom they are not getting prolific visits from the native bees should probably arrange to bring in some honey bee colonies. But even that may not guarantee ample pollination, because there is no way to be sure honey bees will stay on blueberries if there is something else in bloom that is more attractive to them," Sampson added.

"After all, rabbiteye blueberries are native North American bushes and honey bees are not natives so there was no co-evolved adaptation between these species."

Bottom Line: Adults who had pediatric-onset of multiple sclerosis (MS) before they were 18 were more likely to have greater cognitive consequences than patients who developed MS as adults. This study used Swedish registry data and included 5,704 patients with MS (300 of whom had pediatric-onset of the disease), and it compared test scores reflective of information-processing efficiency. Researchers report scores were lower, and declined faster, among patients with pediatric-onset MS compared to patients with adult-onset MS. Additionally, patients with pediatric-onset MS were more likely to experience cognitive impairment. Study limitations include misclassification of patients because the date of MS onset was largely based on self-reported symptoms.

High-flying careers in the airline industry don't mean sky-high salaries for women, according to new research by Swansea University.

The gender pay gap within airlines is often attributed to the fact that men frequently carry out high technically skilled jobs such as pilots and mechanics, whereas women commonly work in customer service roles like cabin crew.

The gender pay gap is a key focus of a new paper, Women in Aviation, written by Geraint Harvey, Joceleyn Finniear and Mrinalini Greedharry, academics at Swansea University's School of Management that has just been published in Research in Transportation Business and Management.

They argue that "the gendered nature of work in the industry means women commonly occupy lower skilled and less structurally important jobs, and as a consequence are more likely to experience insecurity in their work".

The paper acknowledges that the duties carried out by cabin crew and other customer- facing roles - jobs often done by female staff - require a high degree of emotional labour, a skill not valued in the same way as the technical skill of a pilot.

Nonetheless, a key finding of the study is that a gender pay gap exists for cabin crew after controlling for contract type.

Analysing data from a comprehensive study undertaken in 2014 with support of the European Commission by Geraint Harvey and Peter Turnbull, from Bristol University, the School of Management team contrasted the salaries of male and female cabin crew from Italy, Norway, Sweden and the UK.

Their findings show that UK airlines are lagging behind some of their continental counterparts in terms of pay equality.

The analysis revealed little difference between the percentage of male and female cabin crew who reported a guaranteed income of €1,400 or more per month in Sweden and Norway, but a statistically significant difference in the UK.

The team found also found "a statistically significant difference between the gross monthly income of male and female cabin crew in the UK with less than one quarter of female respondents stating a gross monthly income of €2,000 or more in contrast to over half of the male respondents".

The researchers discovered many of the staff were in the difficult position of having to endure the work-related pressures of a full-time role because part-time working wasn't financially feasible.

They also found work insecurity caused by the rearrangement of shifts at short notice could have a detrimental effect on work-life balance and family commitments.

The paper reported: "A high proportion of female respondents (44.1 per cent) stated that they were usually given less than 24 hours' notice for changes to their roster, while a further third (34.3 per cent) state they were usually given between 24 and 48 hours notification of a change."

In analysing the terms and conditions of male and female workers in the industry and finding a deterioration for both groups, the academics concluded it is not so much a case that women do less well than men but that both groups are doing badly with women faring even worse.

The myth that modern wheat varieties are more heavily reliant on pesticides and fertilisers is debunked by new research published in Nature Plants today.

Lead author on the paper, Dr Kai Voss-Fels, a research fellow at The University of Queensland, said modern wheat cropping varieties actually out-perform older varieties in both optimum and harsh growing conditions.

"There is a view that intensive selection and breeding which has produced the high-yielding wheat cultivars used in modern cropping systems has also made modern wheat less resilient and more dependent on chemicals to thrive," said Dr Voss-Fels.

"However, the data unequivocally shows that modern wheat varieties out-perform older varieties, even under conditions of reduced amounts of fertilisers, fungicides and water," he said.

"We also found that genetic diversity within the often-criticised modern wheat gene pool is rich enough to generate a further 23 per cent increase in yields."

Dr Voss-Fels said the findings might surprise some farmers and environmentalists.

"Quite a few people will be taken aback by just how tough modern wheat varieties proved to be, even in harsh growing conditions, such as drought, and using less chemical inputs."

Dr Voss-Fels said the findings could have potentially important implications for raising the productivity of organic cropping systems.
"It's been widely assumed that the older wheat cultivars are more robust and resilient but it's actually the modern cultivars that perform best in optimum and sub-optimum conditions."

Wheat is the world's most important food crop.

However, with global wheat yields reduced due to droughts in recent years and more climate risk anticipated in the future, the hardiness of modern wheat varieties is an issue of global significance.

The study is believed to provide the most detailed description of the consequences of intensive breeding and genetic selection for high grain yield and associated traits in European wheat over the past 50 years.

It was led by Professor Rod Snowdon of the Justus-Liebig-University Gießen (JLU), who is also an honorary Professor at UQ, in collaboration with seven other German universities.

The genetic analysis was undertaken at QAAFI under the leadership of Professor Ben Hayes.

The first part of the study involved testing 200 wheat varieties that have been essential to agriculture in Western Europe in the past 50 years.

Performance was compared between those varieties in side-by-side field trials under high, medium and low chemical input conditions.
The second part of the study was undertaken at QAAFI, to match the performance differences with the different varieties' genetic make-up.

"This genetic information allows us to take the discovery to the next level," Dr Voss-Fels says.

"We can use artificial intelligence (AI) algorithms to predict the optimal crosses needed to bring together the most favourable segments as fast as possible."

New research from Northwestern University finds that balanced professional networks are more important than individual talent when it comes to high-risk decision making.

The study, published today, June 14, in Nature Communications, is the first longitudinal study to prove several key tenants of structural balance theory (SBT), which provides an analytical framework to characterize how relationships change over time. SBT consists of four primary rules for relationships among individuals:

A friend of a friend is a friend

A friend of an enemy is an enemy

An enemy of an enemy is a friend

An enemy of a friend is an enemy

When all of these conditions are met, a network is said to be balanced. Through a two-year study of day traders, the researchers found that: (A) workers gravitate toward a state of balance in their relationships; and (B) performance improves when there is a high level of balance.

"This data shows that companies reap the benefits when conflict among employees is reduced," said corresponding author Brian Uzzi, the Richard L. Thomas Professor of Leadership and Organizational Change in Northwestern's Kellogg School of Management. "There are certain types of conflict that can't resolve themselves. This work can help managers identify those conflicts and actively step in to resolve them, ultimately leading to better performance."

From 2007 to 2009, researchers analyzed day traders' instant messages to determine the relationships among traders and compared those relationships to performance data for individual traders, controlling for factors including market volatility and work days. They found that the traders with the highest level of balance in their networks also made the best trades, regardless of the objective level of talent of any individual trader.

"We suspect that conflict in networks monopolizes some portion of workers' mental energy," Uzzi said. "Resolving that conflict frees up mental energy to make better decisions and perform at a higher level."

The findings of this study apply to individuals who engage in extensive high-risk decision making, particularly in situations where polarization is common, such as politics or in the military.

Further research is needed to determine whether the same rules hold in other work situations, such as creative and innovative endeavors.

Sleep patterns can predict the accumulation of Alzheimer’s pathology proteins later in life, according to a new study of older men and women published in JNeurosci. These findings could lead to new sleep-based early diagnosis and prevention measures in the treatment of Alzheimer’s disease.

Alzheimer's disease is associated with disrupted sleep and the accumulation of tau and proteins in the brain, which can emerge long before characteristic memory impairments appear. Two types of hippocampal sleep waves, slow oscillations and sleep spindles, are synced in young individuals, but have been shown to become uncoordinated in old age.

Matthew Walker, Joseph Winer, and colleagues at the University of California, Berkeley found a decrease in slow oscillations/sleep spindle synchronization was associated with higher tau, while reduced slow-wave-activity amplitude was associated with higher β-amyloid levels.

The researchers also found that a decrease in sleep quantity throughout aging, from the 50s through 70s, was associated with higher levels of β-amyloid and tau later in life. This means that changes in brain activity during sleep and sleep quantity during these time frames could serve as a warning sign for Alzheimer's disease, allowing for early preventive care.

High blood pressure may affect conditions such as Alzheimer's disease by interfering with the brain's waste management system, according to new research in rats published in JNeurosci. Maintaining blood vessel health could therefore help stave off cognitive decline.

Hypertension causes stiffening and elasticity loss in blood vessels, which hinders clearance of waste molecules from the brain. Using a rat model of hypertension, Maiken Negergaard and colleagues at the University of Copenhagen and Yale School of Medicine studied how the condition affects the movement of cerebrospinal fluid into and interstitial fluid out of brain cells.

The researchers tracked the flow of cerebrospinal fluid and found that the hypertensive rats exhibited larger ventricles, decreased brain volume, and impaired fluid transport. They concluded that hypertension interferes with the clearance of macromolecules from the brain, such as the Alzheimer's pathology protein β-amyloid. Treatments targeting hypertension could in turn reduce β-amyloid buildup and delay the onset of Alzheimer's disease.

BUFFALO, N.Y. -- For decades, Big Tobacco has sold African American smokers on menthol-flavored cigarettes through targeted marketing campaigns. That's among the reasons why, in the U.S., black smokers who prefer menthols are 12% less likely to quit smoking compared to non-menthol users, according to the results of a newly published study.

The findings, reported today in the journal Nicotine & Tobacco Research, underscore the role that mentholated cigarettes play in smoking cessation efforts, particularly among African American tobacco users, says the study's lead author, Philip Smith, an assistant professor in the Department of Kinesiology and Health at Miami University (OH).

Menthol cigarettes were first sold in the 1920s. The tobacco industry began targeting African Americans in the 1940s and menthol use grew along with the belief that menthols were less dangerous, according to Gary Giovino, the study's senior author and a professor of community health and health behavior at the University at Buffalo who has extensively studied the marketing and use of menthol cigarettes.

The study -- a meta-analysis of 19 studies plucked from a review of more than 400 abstracts -- looks at the association between menthol use and smoking cessation.

The finding that menthol flavoring was associated with less success in quitting smoking among African Americans wasn't surprising, Smith said. The lack of association for white smokers, however, was.

"Much of the rationale for why menthol flavoring might impede cessation has to do with how menthol flavoring might make the nicotine in cigarettes more reinforcing," Smith said.

"This would be true regardless of race or ethnicity, so we might expect to see menthol flavoring making it more difficult for everyone to quit. The fact that we didn't find consistency across racial and ethnic groups, we think, might point to the causal role of social influences like tobacco marketing," he added.

Big Tobacco's marketing efforts have included heavier advertising of menthols on billboards in predominantly African American neighborhoods, and ads in African American-centric magazines, compared to white communities and periodicals.

In addition, the industry has provided philanthropic support to organizations such as the National Association for the Advancement of Colored People and the National Urban League, Giovino added.

A recent study by Giovino and colleagues suggests that tobacco companies are holding onto the menthol market better than non-menthol cigarettes. "Less quitting by menthol smokers is part of the reason why," he said.

Smokers' inaccurate perceptions of menthol cigarettes have further compounded cessation efforts, Giovino says.

"Some people believe they are less dangerous, even though they are, in epidemiological studies, found to be at least as dangerous as non-mentholated cigarettes," he said. "Menthol is a topical anesthetic that numbs the respiratory tract. People inhale them more easily, which gives the perception of safety."

The idea for the study stemmed from a conversation between Smith and study co-author Biruktawit Assefa, now with Yale University School of Public Health, who worked with Smith when she was an undergraduate intern at Yale.

"We wanted to more conclusively look at whether there are racial differences in how menthol flavoring may impede smoking cessation, across studies published on the topic," Smith said.

Essentially, it's about social injustice, said Smith, who wants to use research "to give power back to communities from which power has been taken."

"It all comes down to power and who has more of it and who has less of it, and why," Smith added. Banning menthol from tobacco products -- which the study recommends -- might help shift the power, he said.

"Such a policy might effectively take some power away from the tobacco industry and give it back to blacks and African Americans in the U.S.," Smith said.

Wearable fitness trackers have made it all too easy for us to make assumptions about our health. We may look to our heart rate to determine whether we really felt the stress of that presentation at work this morning, or think ourselves healthier based on the number of steps we've taken by the end of the day.

But to get a better reading on your overall health and wellness, you'd be better off looking at the strength and structure of your circle of friends, according to a new study in the Public Library of Science journal, PLOS ONE.

While previous studies have shown how beliefs, opinions and attitudes spread throughout our social networks, researchers at the University of Notre Dame were interested in what the structure of social networks says about the state of health, happiness and stress.

"We were interested in the topology of the social network -- what does my position within my social network predict about my health and well-being?" said Nitesh V. Chawla, Frank M. Freimann Professor of Computer Science and Engineering at Notre Dame, director of the Interdisciplinary Center for Network Science and Applications and a lead author of the study. "What we found was the social network structure provides a significant improvement in predictability of wellness states of an individual over just using the data derived from wearables, like the number of steps or heart rate."

For the study, participants wore Fitbits to capture health behavior data -- such as steps, sleep, heart rate and activity level -- and completed surveys and self-assessments about their feelings of stress, happiness and positivity. Chawla and his team then analyzed and modeled the data, using machine learning, alongside an individual's social network characteristics including degree, centrality, clustering coefficient and number of triangles. These characteristics are indicative of properties like connectivity, social balance, reciprocity and closeness within the social network. The study showed a strong correlation between social network structures, heart rate, number of steps and level of activity.

Social network structure provided significant improvement in predicting one's health and well-being compared to just looking at health behavior data from the Fitbit alone. For example, when social network structure is combined with the data derived from wearables, the machine learning model achieved a 65 percent improvement in predicting happiness, 54 percent improvement in predicting one's self-assessed health prediction, 55 percent improvement in predicting positive attitude, and 38 percent improvement in predicting success.

"This study asserts that without social network information, we only have an incomplete view of an individual's wellness state, and to be fully predictive or to be able to derive interventions, it is critical to be aware of the social network structural features as well," Chawla said.

The findings could provide insight to employers who look to wearable fitness devices to incentivize employees to improve their health. Handing someone a means to track their steps and monitor their health in the hopes that their health improves simply may not be enough to see meaningful or significant results. Those employers, Chawla said, would benefit from encouraging employees to build a platform to post and share their experiences with each other. Social network structure helps complete the picture of health and well-being.

"I do believe these incentives that we institute at work are meaningful, but I also believe we're not seeing the effect because we may not be capitalizing on them the way we should," Chawla said. "When we hear that health and wellness programs driven by wearables at places of employment aren't working, we should be asking, is it because we're just taking a single dimensional view where we just give the employees the wearables and forget about it without taking the step to understand the role social networks play in health?"

Young adults who live in neighborhoods with more medical marijuana dispensaries use marijuana more frequently than their peers and have more-positive views about the drug, according to a new RAND Corporation study.

The associations were strongest among young adults who lived near dispensaries that had storefront signs, suggesting that regulating such advertising could be one strategy if policymakers were concerned about curbing use of marijuana. Based on research from this same project, the city of Los Angeles adopted an ordinance in 2018 to restrict some storefront and billboard advertising.

The study, which examined a group of people aged 18 to 22 who lived in Los Angeles County in 2016-17, is the first to show that storefront marijuana signage is extremely influential and substantially magnifies the associations between higher density of medical marijuana dispensaries with greater use of marijuana and positive views about the drug. The study is published online by the journal Addiction.

"Our findings suggest that as the marijuana retail outlets become more visible and more numerous, they may influence the way that young adults perceive and use marijuana," said Regina Shih, the study's lead author and a senior behavioral scientist at RAND, a nonprofit research organization.

California was the first state to legalize medical marijuana in 1996, with 33 states now having some type of medical marijuana law. In addition, California and nine other states allow the sale of marijuana for recreational use.

Although research supports some medicinal benefits of marijuana, youth who frequently use marijuana are more likely to experience negative consequences such as increased risk of mental and physical health problems, school drop-out, relationship problems and motor vehicle accidents.

RAND researchers analyzed survey results from 1,887 people aged 18 to 22 who live in Los Angeles County and have been long-term participants in an ongoing RAND project examining multiple factors about the use of alcohol, marijuana and other drugs. Most of those in the study were in college or trade school at the time of the survey.

The study used geocoding techniques and multiple data sources about marijuana businesses to determine the density of medical marijuana dispensaries within four miles of participants' homes. It is the first analysis to account for the socioeconomic status of the neighborhood and medical marijuana card ownership, and used validated methods to locate and verify medical marijuana dispensary availability.

Researchers found that nearly 85 percent of the study participants lived within four miles of 10 or more medical marijuana dispensaries.

Living near more medical marijuana dispensaries was associated with using marijuana on a greater number of days over the past month and with higher positive expectations about marijuana.

Living near more medical marijuana dispensaries that had storefront signage was associated with a four- to six-times larger effect both on marijuana usage and on positive expectations about marijuana.

"Attention is needed on access to marijuana for young adults, as marijuana use is most prevalent among this age group and is also associated with increased risk for several substance use disorders," Shih said.

Researchers say that as the marketplace for medical and recreational marijuana change rapidly, future studies should track whether access to recreational dispensaries influences youth marijuana use and risk factors over time.

A chubby teen lolling on the sofa for hours on end, the game controller in one hand, a bag of crisps at his side and a bottle of coke on the coffee table. This is the mental picture many people have of the typical gamer. Along with this goes the widespread notion that frequent gaming contributes to obesity. Is this justified?

"The study contradicts this stereotype for children and teenagers. In adults, there is a slight positive correlation between playing video games and body mass," explains Professor Markus Appel, a communication psychologist at the University of Würzburg. Researchers from the University of Würzburg (Markus Appel, Caroline Marker) and from the Johannes Kepler University Linz and the Leibniz Institute for Educational Trajectories in Bamberg (Professor Timo Gnambs) conducted a meta analysis comprising a total of 20 relevant studies with more than 38,000 participants. However, the analysis revealed only a small correlation between video game playing and excess weight or body mass. Only one percent of a person's overweight can thus be attributed to time spent playing computer games.

No link in children and teenagers

The link was only established for adults but not for children and teenagers. "It may be that people who are overweight are more likely to continue their hobby of playing video games during the transition to adulthood whereas new leisure time activities become more important for others," Appel suggests.

In the past, the link between gaming and overweight has already been studied by several researchers. "Overweight and obesity are usually associated with sedentary media consumption such as watching television or playing non-active video games," the team of researchers writes in its current study published in the journal Social Science and Medicine. The new meta analysis was launched because the individual studies yielded different results.

Less time exercising

How can the correlation be explained? "We identified a significant indirect effect which shows that people who spend more time playing video games also spend less time exercising and therefore weigh more or have more body mass," the team from Würzburg and Linz writes. Other factors such as eating junk food while gaming or lack of sleep were not verified because there were not enough relevant studies available.

The scientists considered only sedentary video games in their current analysis - i.e. games that are played in a sitting position. Active video games such as Wii Sports or Pokémon Go, which require the players to move, were not taken into consideration.

CATONSVILLE, MD, June 17, 2019 - While serious economic and societal issues continue to swirl around the gender pay gap, new research published in the INFORMS journal Organization Science shows one area where this inequality is starting to disappear--higher education. Researchers have found that the gender pay gap disappears at more prestigious universities.

The research, conducted by Dane Blevins of the University of Central Florida, Steve Sauerwald of the University of Illinois at Chicago, Jenny Hoobler of the University of Pretoria, and Chris Robertson of Northeastern University is based on 17 years of data from more than 1,100 university presidents working for more than 700 universities in the United States. The status of universities in the study is determined by data collected from U.S News & World Report's Best College Rankings.

While the study reveals that in higher education there is typically a 9 percent compensation difference between male and female presidents, with women receiving less pay than men on average, at higher status universities, female presidents are receiving similar levels of total compensation as male presidents- and some are even earning more than male presidents at prestigious universities.

"Our research finds accounting for where the glass ceiling is broken is an important consideration in understanding the gender pay gap," said Blevins, an associate professor in the Department of Management at the University of Central Florida. "Higher status universities are often viewed as guideposts and their standard of compensation among female presidents may encourage other universities, businesses and organizations of all types, to follow suit and further reduce, if not close, the gender pay gap in the United States."