Earth

Stimulating immune cells with two cancer immunotherapies together can shrink the size of the viral "reservoir" in SIV (simian immunodeficiency virus)-infected nonhuman primates treated with antiviral drugs, Emory University researchers and their colleagues have concluded. The reservoir includes immune cells that harbor virus despite potent antiviral drug treatment.

The findings, reported in Nature Medicine, have important implications for the quest to cure HIV because reservoir shrinkage has not been achieved consistently before. However, the combination treatment does not prevent or delay viral rebound once antiviral drugs are stopped. Finding an HIV cure is of critical importance as, although antiretroviral therapy can reduce the amount of circulating virus to undetectable levels, problematic issues remain such as social stigma in addition to the long-term toxicity and cost of antiretroviral drugs.

"It's a glass-half-full situation," says senior author Mirko Paiardini, PhD. "We concluded immune checkpoint blockade, even a very effective combination, is unlikely to achieve viral remission as a standalone treatment during antiretroviral therapy."

He adds the approach may have greater potential if combined with other immune-stimulating agents. Or it could be deployed at a different point -- when the immune system is engaged in fighting the virus, creating a target-rich environment. Other HIV/AIDS researchers have started to test those tactics, he says.

Paiardini is an associate professor of pathology and laboratory medicine at Emory University School of Medicine and a researcher at Yerkes National Primate Research Center. The study performed in nonhuman primates, considered the best animal model for HIV studies, was carried out in collaboration with co-authors Shari Gordon and David Favre at the University of North Carolina at Chapel Hill and GlaxoSmithKline; Katharine Bar at the University of Pennsylvania; and Jake Estes at Oregon Health & Science University.

Although antiviral drugs are available that can suppress HIV to the point of being undetectable in blood, the virus embeds itself in the DNA of immune cells, frustrating efforts to root it out. Only two individuals have ever achieved what their doctors consider a durable cure, and they went through a bone-marrow transplant for leukemia or lymphoma -- not widely applicable.

Paiardini and his colleagues reasoned chronic viral infection and cancer produce similar states of "exhaustion": immune cells (T cells) that could fight virus or cancer are present, but unable to respond. In long-term HIV or SIV infection, T cells harboring the virus display molecules on the cell surface that make them targets for checkpoint inhibitors, cancer immunotherapy drugs that are designed to counteract the exhausted state. In the context of HIV infection, these types of drugs have been tested to a limited extent in people living with HIV who were being treated for cancer.

In the Nature Medicine paper, the researchers used antibodies to block the surface molecules CTLA-4 and PD-1. In monkeys that received both CTLA-4- and PD-1-blocking agents, researchers observed a stronger activation of T cells, compared to only PD-1 blockade. DNA sequencing of viruses in the blood revealed a broader range of viruses were reactivated with the combination, compared to single checkpoint inhibitors.

"We observed that combining CTLA-4- and PD-1 blockade was effective in reactivating the virus from latency and making it visible to the immune system," Paiardini says.

In previous studies, limited shrinkage of the viral reservoir has been seen only inconsistently with single checkpoint inhibitors or other immune-stimulating agents. Only combination-treated animals showed a consistently measurable and significant reduction in the size of the viral reservoir. The researchers measured this with "DNAscope," an imaging technique to visualize infected cells within tissues. Additionally, researchers quantified the frequency of CD4 cells, the main reservoir of HIV and SIV, harboring intact viral DNA capable of replicating.

Despite this effect, once antiviral drugs were stopped, the virus still came back to the same level in combination-treated animals.

"We believe this is due to having much less viral antigens around after long-term antiretroviral therapy, compared with the situation in cancer," says Justin Harper, lab manager and first author of the paper. "This makes it much more difficult for the immune system to recognize and kill those cells."

A note of caution: the equivalent combination of CTLA-4 and PD-1 blockade in humans has been tested in the context of cancer treatment. While the two drug types can be more effective together, patients sometimes experience adverse side effects: severe inflammation, kidney damage, or liver damage.

In the Nature Medicine paper, the combination-treated animals did not experience comparable adverse events, the researchers reported. Further investigation is necessary to determine whether the combination of checkpoint inhibitors exhibits an acceptable toxicity profile in people living with HIV without cancer.

Paiardini credits the Yerkes National Primate Research Center Animal Resources team for their dedicated care of the animals involved in the study. HIV studies are complex and long-term, so animal care is the backbone of being able to conduct such research focused on improving human health.

A major advance in revealing the unknown plant diversity on planet Earth is made with a new monograph, published in the open-access, peer-reviewed journal PhytoKeys. The global-wide study, conducted by researchers at the University of Oxford, lists details about each of the 425 New World species in the largest genus within the family of morning glories, thanks to an all-round approach combining standard, modern and new-generation identification techniques.

The family of morning glories, also known as bindweeds, whose scientific name is Convolvulaceae, includes prominent members like the sweet potato and ornamental plants such as the moonflower and the blue dawn flower. In fact, one of the key conclusions, made in the present work, is that within this plant group there are many other species, besides the sweet potato, that evolved storage roots long before modern humans appeared on Earth. Furthermore, most of those are yet to be evaluated for economic purposes.

To make their findings, the research team of John Wood, Dr Pablo Muñoz Rodríguez, Bethany R.M. Williams and Prof Robert Scotland applied the "foundation monograph" concept that they had developed for similarly diverse and globally distributed, yet largely understudied groups. Usually, such groups with hundreds of species have never been surveyed across their entire geographical range, which in turn results in the existence of many overlooked new species or species wrongly named.

As a result, the monograph adds six new to science species and establishes nine new subspecies, previously recognised as either distinct species or varieties. The publication also cites all countries where any of those 425 morning glories occurs. In order to provide detailed knowledge about their identities and ecologies, the authors also produced over 200 illustrative figures: both line drawings and photos.

In their study, the scientists also investigate poorly known phenomena concerning the genus. For instance, the majority of the plants appear to originate from two very large centres, from where they must have consequently radiated: the Parana region of South America and the Caribbean Islands. Today, however, a considerable amount of those species can be found all around the globe. Interestingly, the team also notes a strong trend for individual species or clades (separate species with a common ancestor) to inhabit disjunct localities at comparable latitudes on either side of the tropics in North America and South America, but not the Equator.

The monograph exemplifies the immense value of natural history collections. Even though the researchers have conducted fieldwork, most of their research is based on herbarium specimens. They have even managed to apply DNA sequencing to specimens over 100 years old. The publication also provides detailed information about the characteristics, distribution and ecology of all the species. It is illustrated with over 200 figures, both line drawings and photos.

"A major challenge in monographing these groups is the size of the task given the number of species, their global distribution and extensive synonymy, the large and increasing number of specimens, the numerous and dispersed herbaria where specimens are housed and an extensive, scattered and often obscure literature," comment the scientists.

"Unlike traditional taxonomic approaches, the 'foundation monograph' relies on a combination of standard techniques with the use of online digital images and molecular sequence data. Thereby, the scientists are able to focus on species-level taxonomic problems across the entire distribution range of individual species," they explained.

A major challenge in neuroscience lies in understanding how molecular and circuit differences in the brain synergistically contribute to sex differences in behavioral phenotypes. Sex differences in the brain may arise from the identity, distribution and relative abundance of cell types.

The cannabinoid 1 receptor (CB1R), the main receptor for cannabinoids and endocannabinoids (eCB), is the most abundantly expressed G protein-coupled receptor in the brain and is highly conserved in animal evolution. However, whole-brain mapping of CB1R expression in adult male and female mice had not previously been described in detail.

Recently, a research team led by Dr. WANG Feng from the Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences demonstrated that CB1R mRNA expression displays a sexually dimorphic pattern in several regions in the adult mouse brain.

According to their current study published in Journal of Comparative Neurology on January 29, a systemic mapping of CB1R mRNA expression was conducted and compared for the first time in male and female adult C57BL/6J mouse (a common inbred strain of laboratory mouse) brains.

The researchers found that the neocortex, medial habenula, striatum, hippocampus and cerebellum were enriched with CB1R mRNA signals.

In the orbital cortex, insular cortex, cingulate cortex, piriform cortex, secondary visual cortex, caudate putamen and ventral hippocampus CA1, there were significantly more CB1R positive cells in males than in females. On the contrary, in the fornix and dorsal hypothalamus, CB1R positive cells were displayed more in females.

It is plausible that the difference in CB1R expression in the brain contributes to sex differences in various phenotypes. For example, the striatum, which harbors a greater amount of CB1R positive cells in males, has been widely recognized as the main affected region in Parkinson's disease, which has a higher incidence in males. The dorsal hypothalamus, with a female-biased number of CB1R positive cells, is associated with maternal behaviors.

More interestingly, CB1R mRNA seems to fluctuate with the estrus cycle in female brain regions, including the medial amygdala, basolateral amygdala and parabrachial nucleus, which has not been reported before.

This study maps the localization of CB1R positive cells on a whole-brain scale in both genders for the first time. The findings provide a basis for understanding sexual dimorphism in physiological and pathological brain functions related to cannabinoids and endocannabinoids.

WASHINGTON, D.C. (March 16, 2020)--Latino/a adolescents with a family member who was detained or deported beginning as early as 2017 were at high risk of suicidal thoughts, early alcohol use, and risky behaviors that can lead to school failure and chronic health problems. The findings were published today in JAMA Pediatrics.

"Our study offers the first direct scientific evidence indicating that current U.S. immigration policies might contribute to serious mental and behavioral health risks for Latino/a youth," said Kathleen M. Roche, MSW, PhD, an associate professor of prevention and community health at the George Washington University Milken Institute School of Public Health (Milken Institute SPH). "A deportation or detention in the family may put these young people, most of whom are U.S. citizens, at risk of serious health problems and a downward trajectory that could be hard to reverse."

Since early 2017, the U.S. government has announced or put in place numerous immigration policy changes, such as a substantial push to detain or deport many immigrants, including those who had lived and worked in the United States for many years. In this study, Roche and her colleagues surveyed 547 Latino/a youth attending middle or high school in suburban Atlanta. Most of the students were 11 to 14 years old when enrolled in the study and had been born in the United States.

Roche and her colleagues asked the young participants if they had a parent, aunt, uncle or other family member who had been detained or deported in the prior year, a time frame including 2017 and 2018. "We were startled to find that one out of four of the students reported having a family member who had been detained or deported in that time frame," Roche said.

The researchers surveyed the participants again six months later asking if they had experienced suicidal thoughts, used alcohol, or engaged in risky behaviors such as aggression or delinquency during the time between the first and second survey.

The team found that tweens and teens with a family member who had been detained or deported had more than twice the risk of suicidal thoughts, a warning sign that can lead to a suicide attempt.

These same Latino/a youth also had nearly three times the risk of reporting early alcohol use. Youth who report drinking alcohol during early and middle adolescence are at higher risk of developing a substance abuse disorder later in life, Roche said.

The team found the same group of teens were also more likely to show a high level of problem behaviors, such as aggression or truancy. These so-called externalizing behaviors are frequently a reaction to trauma exposure. Contrary to any assumption that teens in immigrant families are already likely to show such behaviors, this study shows the increase occurred after family members were deported or detained, Roche said.

"This study found that among kids with a deportation or detention in the family, 28 percent later reported thinking of killing themselves sometimes or often; 18 percent said they had consumed alcohol and 23 percent had engaged in a high level of risky behavior," Roche said. "The findings are worrisome because these kinds of risks during the early teen years often result in problems well into adulthood."

Roche cautions that one study alone cannot provide hard and fast proof that the current U.S. immigration policies are harming Latino/a youth. She adds that adolescents engage in risky behaviors and have thoughts of suicide for reasons other than a deportation or detention in the family.

"However, this study controlled for important factors such as the quality of parent-child relationships and risk behaviors reported at the study's start," Roche said. "We still found a strong association with deportation or detention of a family member and the threat of serious behavioral, mental health, and social problems among young adolescents."

The findings add to concerns about the long-term public health impact of deportations, detentions, and other immigration policies on Latino/a families. A study published by Roche in 2018 looked at Latino/a parents and found that changes in U.S. immigration policies may have triggered clinical levels of anxiety and fear--distress that can be passed along to their children.

And in a study published Jan. 6, 2020 in the Journal of Family Issues, Roche and her colleagues conducted focus groups with Latino/a parents, finding that many reported fear and daily life stressors related to U.S. immigration policies. In that study, parents, most of whom were legal residents or U.S. citizens, reported they and their teenage children were subjected to a pervasive uptick in discriminatory comments at work, school or out in public.

In the new study, the researchers focused on teenagers because they are old enough to be involved in family discussions about a pending deportation or detention and can be exposed to more fear and anxiety surrounding that process compared to younger children.

In addition, adolescents are at a vulnerable stage of life when trauma exposure is related to changes in brain structure, Roche said. Prior research suggests that, without mental health services, teens exposed to a trauma like family separations are at risk of post-traumatic stress disorder and chronic mental health problems, including depression or drug and alcohol use. Mental health problems can also lead to difficulties in school or on the job.

"Our findings indicate a critical need for mental health and social services that can ease the stress and trauma facing U.S. Latino/a teens," Roche said, adding that teachers and health care professionals should be alert to early signs of distress in Latino/a youth. "As shown in this study, the current immigration policies may be threatening the health and well-being of future generations."

What The Study Did: Researchers in this survey study of nearly 550 Latino or Latina adolescents looked at how family member detention or deportation was associated with later suicidal thoughts, alcohol use or clinically significant externalizing behaviors such as rule-breaking and aggressive behaviors.

Author: Kathleen M. Roche, Ph.D., of George Washington University in Washington. D.C., is the corresponding author.

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

(doi:10.1001/jamapediatrics.2020.0014)

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

New insights into the architecture of the brain have been revealed by scientists at the Wellcome Sanger Institute, the Wellcome-MRC Cambridge Stem Cell Institute and their collaborators. The researchers discovered that cells in the cerebral cortex of mice, called astrocytes, are more diverse than previously thought, with distinct layers of astrocytes across the cerebral cortex that provide the strongest evidence to date of their specialization across the brain.

Published today (16 March) in Nature Neuroscience, the most in-depth study of its kind is set to change the way we think about the brain and the role of cells such as astrocytes. This knowledge will have with implications for the study of neurological disorders, such as Alzheimer's, multiple sclerosis and autism.

In the past 20 years, research has shown glial cells to be key players in brain development and function, as well as promising targets for better understanding neurological disorders. Alzheimer's causes around two thirds of dementia cases in the UK, which affects around 850,000 individuals at present*. MS is a neurological disorder that affects the central nervous system and impacts around 100,000 people in the UK**. Autism affects around one in every hundred people in the UK***.

'Glial' comes from the Greek word for 'glue' or 'putty'. At one time, glial cells were thought of as 'brain putty' - functionally similar, passive cells whose only function was to fill the space around the 'all important' neurons. However, new studies are showing their critical importance in regulating neuron functions^. Astrocytes are a type of glial cell, so called because of their 'star-shaped' structure^^.

Despite the wealth of knowledge on neuronal function and the organisation of neurons into layers, prior to this study there had been little investigation into whether glial cells across different layers showed different cellular properties. To answer this question, the researchers developed a new methodological approach to provide a more detailed view of the organisation of astrocytes than ever before.

Nucleic acid imaging was carried out on mouse and human brain samples at the University of Cambridge to map how new genes are expressed within tissue. These maps were combined with single cell genomic data at the Wellcome Sanger Institute to extend the molecular description of astrocytes. These data sets were then combined to create a three-dimensional, high-resolution picture of astrocytes in the cerebral cortex.

The team discovered that astrocytes are not uniform as previously thought, but take distinct molecular forms depending on their location in the cerebral cortex. They found that astrocytes are also organised into multiple layers, but that the boundaries of astrocyte layers are not identical to the neuronal layers. Instead, astrocyte layers have less sharply defined edges and overlap the neuronal layers.

Dr Omer Bayraktar, Group Leader at the Wellcome Sanger Institute, said: "The discovery that astrocytes are organised into layers that are similar, but not identical to, neuronal layers redefines our view of the structure of the mammalian brain. The structure of the cerebral cortex can no longer simply be seen as the structure of neurons. If you want to properly understand how our brains work, you have to consider how astrocytes are organised and what role they play."

As well as increasing our understanding of brain biology, the findings will have implications for the study and treatment of human neurological disorders. Over the past decade glial cells, rather than neurons, have been heavily implicated in diseases such as Alzheimer's and multiple sclerosis.

Professor David Rowitch, senior author of the study and Head of Paediatrics at the University of Cambridge, said: "This study shows that the cortical architecture is more complex than previously thought. It provides a basis to begin to understand the precise roles played by astrocytes, and how they are involved in human neurodevelopmental and neurodegenerative diseases."

Arctic and Antarctic ice loss will account for about one-fifth of the warming that is projected to happen in the tropics, according to a new study led by Mark England, a polar climate scientist at Scripps Institution of Oceanography at the University of California San Diego, and Lorenzo Polvani, the Maurice Ewing and J. Lamar Worzel Professor of Geophysics at Columbia Engineering, England's doctoral supervisor.

While there is a growing body of research showing how the loss of Arctic sea ice affects other parts of the planet, this study is the first to also consider the long-range effect of Antarctic sea ice melt, the research team said.

"We think this is a game-changer as it shows that ice loss at both poles is crucial to understanding future tropical climate change," England said of the study funded by NASA and the National Science Foundation. "Our study will open a hitherto unexplored direction and motivate the science community to study the large effects that Antarctic sea ice loss will have on the climate system."

The years 2017 and 2018 set records for minimum sea ice extent in Antarctica. England and colleagues from Columbia University's School of Engineering, Colorado State University, and the National Center for Atmospheric Research in Colorado used computer simulations to see what scenarios play out near the equator if that decline continues through the end of the century. They found that Antarctic sea ice loss combines with Arctic sea ice loss to create unusual wind patterns in the Pacific Ocean that will suppress the upward movement of deep cold ocean water. This will trigger surface ocean warming, especially in the eastern equatorial Pacific Ocean. Warming there is a well-known hallmark of the El Niño climate pattern that often brings intense rains to North and South America and droughts to Australia and other western Pacific countries.

As that surface ocean water warms, it will also create more precipitation. Overall, the researchers believe the ice loss at both poles will translate to a warming of the surface ocean of 0.5? (0.9?) at the equator and add more than 0.3 millimeters (0.01 inches) of rain per day in the same region.

This study joins several new analyses of the global impact of polar ice loss, including a January analysis by Scripps Oceanography physicist Charles Kennel suggesting that shrinking Arctic ice might change key characteristics of El Niño in the future.

Measures against overfishing tend to protect young, immature fish through measures such as minimum-landing sizes. However, a team of researchers led by Professor Robert Arlinghaus from the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB) and the Humboldt-Universität zu Berlin recommends also keeping the particularly large megaspawners alive in addition to the youngsters. This type of management achieves good compromises between the demands of commercial and recreational fisheries and the desire to conserve the reproductive capacity of fish populations.

The aim of traditional fisheries management is to conserve the stocks being fished in the long term and at the same time to maximize biomass yields. Every wild fish should spawn at least once before it lands on our plate. Commercial and recreational fisheries are therefore not allowed to keep animals below a legally defined minimum size - the minimum-length limit. Large, mature specimens, by contrast, can be fished intensively. The key underlying assumption is that these animals have already contributed to the next generation and that the individual growth rate slows with age.

The fish must fit through the "window"

Fisheries professor Robert Arlinghaus from IGB and Humboldt-Universität zu Berlin worked with three fisheries biologists from the University of Florida and Vancouver to investigate the optimal size-based harvest regulations for a wide range of fish species such as pike, zander and cod, and whether it would be reasonable to also conserve the particularly large fish. These large fish are disproportionally fecund as they invest into reproduction and not personal growth. The researchers compared the effect of classical minimum-length limits with less popular harvest regulation - harvest slots. With the harvest slots, only medium-sized fish are taken home for dinner - figuratively speaking, only fish that fit exactly in the intermediate size window. All animals that reach over the frame or are too small should stay in the water to reproduce.

No fishing losses despite protection of the large spawning fish

The researchers found that if only the kilogramm yield that a wild exploited stock is to produce is to be maximized, a minimum-length limit is the appropriate regulation. However, other conservation and fisheries objectives usually also count. These include, for example, a naturally composed spawning fish stock, maintaining of catch rates or a certain size of fish in the catch. "Unfortunately, there is a persistent view that the protection of large spawning fish in an exploited fish stock is counterproductive to fishing and costs potential yield. Based on our work this is outdated. Protecting the large animals stabilizes the population dynamics without causing any relevant loss in yields and increases the average size of the fish in the catch. Harvest slots can outperform the classic minimum-length limit when intensively exploited stocks, such as the pike populations in the coastal waters around Rügen, are fished jointly by commercial and recreational fishers and the big fish are also important for nature conservation and fishing quality," Robert Arlinghaus sums up the results.

The age diversity makes sense ecologically

Looking at the ecology, it becomes clear why the large spawning fish should not be missing in a population: a single particularly large female can compensate for the egg count of many small fish. Furthermore, fish of different sizes and ages reproduce at different times and often in different locations. If environmental events destroy the brood of a period, an age-mixed population can still ensure offspring and thus contribute to more stable populations. In addition, old and young have different habitats, migratory routes and feeding schedules, and young fish learn from the experienced leaders. And in many species mate choice also depends on the length of fish.

"If, through intensive fishing, a fish population is created in which predominantly young fish that have just reached sexual maturity are represented, this has a negative effect on many levels: on the reproductive performance of the stock, on the food web and the ecosystem - and also on the quality of the fishery," concludes Robert Arlinghaus.

ITHACA, N.Y. - In 2017, when interviewers asked Latino community members in San Antonio, Texas, about their top environmental concerns, the answers took researchers by surprise.

Poverty. Inequality. Education. Racism.

"They started bringing up things that don't typically come up in environmental studies," said Neil Lewis Jr., assistant professor of communication in the College of Agriculture and Life Sciences at Cornell University. "So, we decided to conduct a survey to see if this was something unique to the group in San Antonio, or if it's a broader phenomenon."

The survey - conducted among more than 1,100 U.S. residents - found that there were, in fact, demographic differences in how people viewed environmental issues, with racial and ethnic minorities and lower-income people more likely to consider human factors such as racism and poverty as environmental, in addition to more ecological issues like toxic fumes from factories or car exhaust.

Their findings were detailed in "What Counts as an Environmental Issue? Differences in Issue Conceptualization by Race, Ethnicity and Socioeconomic Status," which published in the Journal of Environmental Psychology. Lewis co-authored the paper with researchers including senior author Jonathon Schuldt, associate professor of communication. The paper's first author is Hwanseok Song, formerly a doctoral student in the Department of Communication and now an assistant professor of communication at Purdue University.

"The racial minority and low-income participants in our sample reach different conclusions about what counts as an environmental issue from our whiter and wealthier participants," Lewis said. "And the reason we think this is happening is because of the differences in where people live. Given the nature of stratification and segregation in the U.S., minorities tend to live in places with more exposure to environmental hazards. And so, it's easier to see that these other issues in society, like poverty and racism, are likely to affect environmental outcomes."

Understanding how different groups of people view environmental issues is important when building coalitions to seek environmental justice, Lewis said. Marginalized people are underrepresented when it comes to making environmental decisions, according to the researchers, and understanding which issues motivate them could help inspire them to take action.

"You could go out and talk about climate change and invasive species, but those might not be what really counts as the leading environmental issues for the communities you want to reach," Schuldt said. "For certain communities the most pressing environmental issue might be the flooding that prevents their kids from enjoying the city park. It might be related to drug use. So, I think this work can reorient our thinking about how to inspire engagement."

In future work, the researchers hope to further explore these differences using the mobile communication lab, which allows them to travel to communities that can be otherwise difficult to access, to get more detailed information about respondents and their perspectives.

"The conventional wisdom is, we have multiple sets of issues in our society," Lewis said. "We have environmental issues like climate change, and we have inequality issues like poverty and racism. And these are things that are in separate buckets. But there is a set of people who know that these are all intertwined, and we should look at them together in a more holistic way."

There are plenty of good reasons to make sure children get enough sleep, but their parents' evening peace is nowhere near the most important one.

"If we make sure our children get enough sleep, it can help protect them from mental health problems," says Bror M. Ranum, a PhD candidate at the Norwegian University of Science and Technology's (NTNU) Department of Psychology.

A study of almost 800 children followed over several years shows that those who get the fewest hours of sleep are at greatest risk of developing psychiatric difficulties later, including ADHD, anxiety and depression.

"We're seeing an association between sleep duration and a risk of symptoms of emotional and behavioural disorders," says Ranum, first author of a new article on children, sleep and risk of mental health disorders.

Boys who sleep fewer hours have an increased risk of developing behavioural issues. Both girls and boys who get less sleep are at greater risk for future emotional problems. The measurements do not indicate anything about the quality of sleep.

Children's sleep was measured with motion sensors every night for a week. The researchers conducted clinical interviews to measure mental health difficulties. These procedures were repeated several times every two years.

The study is part of the Tidlig Trygg I Trondheim project (TtiT - Trondheim Early Secure Study). This is a long-term study that has examined nearly a thousand children when they were 4, 6, 8, 10, 12 and 14 years old. The survey of 16-year-olds in the project has just started. Among the many goals of TtiT is to explore why some children develop mental health problems. https://www.ntnu.no/tidlig-trygg

The study also investigated whether psychological difficulties might cause children to sleep less. The data do not indicate this to be the case. Sleep duration influences the risk of later problems, not the opposite.

"Previous studies have also shown that sleep is related to mental health difficulties. But our study is one of the first to investigate this in children over several years, and to use an objective measurement of sleep," says senior author Silje Steinsbekk at NTNU's Department of Psychology.

Because people tend to be quite poor at reporting how much sleep they get, scientists cannot completely rely on people's self-reported sleep duration data. Self-reported sleep duration does not correlate with objective sleep duration measurements. Laboratory studies measure sleep objectively, but this research study is measuring only the immediate effects and does not comment on whether sleep duration affects individuals' psychiatric health over time.

"Our study shows that the children who sleep fewer hours than others more often develop psychiatric symptoms, even two years later," says Steinsbekk.

Ranum emphasizes that big individual differences exist when it comes to how much sleep each child needs.

What amounts to too little sleep for one child may be more than enough for other kids. So parents shouldn't worry unnecessarily either.

"But if you find that your child seems to be under the weather and can't concentrate, or you notice their mood fluctuate more than normal, then you may want to help them get more sleep," Ranum says.

He says it is difficult to give advice that fits for all families and all children. But having a consistent wake-up time in the morning is perhaps the most important way to develop healthy sleep habits.

And maybe future research will show that sleep can help in treating children's mental health problems.

The research group has also investigated how many people get too little sleep, and whether or not too little sleep tends to persist throughout childhood.

Very few six-year-olds (1.1%) slept less than 7 hours, which is below the internationally recommended sleep guidelines for this age group.

But as the children got older, the number who were not getting enough sleep gradually increased (at age 8: 3.9%; age 10: 4.2% and age 12: 13.6%).

Children who were getting too little sleep when they were 6 years old did not necessarily suffer from a lack of sleep when they got older, with most of them meeting the recommended sleep duration. But if insufficient sleep started later, at age 10 for example, the habit tended to persist. Fewer of these children outgrew their insufficient sleep pattern as they got older.

The study results were based on the average measurement of sleep over a whole week. Could this hide many individual nights with too little sleep? Or was there perhaps a difference between weekdays and weekends?

The researchers counted the number of individual nights with less than 7 hours of sleep per week and found that quite a lot of children experienced one or more nights with less than 7 hours of sleep (age 6: 15.1%; age 8: 39.1%; age10: 45.7%; age 12: 64.5%).

In other words, more children had single nights with too little sleep compared to how many on average (over a week) slept too little. Those who had individual nights with fewer sleep hours continued this pattern as they aged, suggesting that such a sleep pattern often did not change.

"Six- to ten-year-olds tended to sleep less on weekends. This trend flipped between the ages of ten and twelve, when longer sleep times on weekends and not enough sleep on weekdays became more common," says Lars Wichstrøm, also at NTNU's Department of Psychology and a co-author of the study.

"We don't know what the consequences are of a few nights here and there with too little sleep. But we do know that after a night without enough sleep, we're moodier and less able to concentrate, which can affect how we function that day, including at school. So it's advisable to get enough sleep," says Steinsbekk.

But remember that most children who average too little sleep over the course of a week won't continue that pattern. The vast majority of children outgrow insufficient sleep habits.

The study findings suggest that parents don't need to worry unnecessarily. Some adjustments to sleep routines may be advisable if your child is affected by lack of sleep. But more major measures may not be needed.

NASA's Aqua satellite passed over the Southern Indian Ocean and captured an image of a well-developed Tropical Cyclone Herold at hurricane strength, east of Madagascar.

Herold formed on March 13 as Tropical Cyclone 22S and once it intensified into a tropical storm, it was renamed Herold. Herold continued to strengthen and is now at hurricane-force.

On March 16, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua satellite provided forecasters with a visible image of Tropical Cyclone Herold and showed a well-developed hurricane with a visible eye, although slightly obscured by high clouds. Powerful bands of thunderstorms circled the eye.

At 5 a.m. EDT (0900 UTC) on March 16, the center of Tropical Cyclone Herold was located near latitude 15.7 degrees south and longitude 54.2 degrees east, about 295 nautical miles north-northwest of St. Denis, La Reunion Island. Maximum sustained winds were near 80 knots (92 mph/148 kph).

The Joint Typhoon Warning Center or JTWC noted that Herold is forecast to turn to the southeast, passing just west of Rodrigues. The storm will strengthen to 90 knots (104 mph/167 kph) later today before becoming subtropical.

Tropical cyclones/hurricanes are the most powerful weather events on Earth. NASA's expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

By Rob Gutro
NASA's Goddard Space Flight Center

A LEGO brick could survive in the ocean for as many as 1,300 years, according to new research.

A study led by the University of Plymouth examined the extent to which items of the ever-popular children's toy were worn down in the marine environment.

By measuring the mass of individual bricks found on beaches against equivalent unused pieces and the age of blocks obtained from storage, researchers estimated that the items could endure for anywhere between 100 and 1,300 years.

They say it once again reinforces the message that people need to think carefully about how they dispose of everyday household items.

The research, published in the journal Environmental Pollution, focused on bricks of LEGO found washed up on the coastlines of South West England.

Over the past decade, voluntary organisations from Cornwall - including Rame Peninsula Beach Care and the LEGO Lost at Sea Project - have retrieved thousands of pieces and other plastic waste during regular beach cleans.

Previous studies have indicated that many of these could have either been lost during beach visits or entered the environment via the household waste process.

For this particular study, 50 pieces of weathered LEGO - constructed of acrylonitrile butadiene styrene (ABS) and collected from beaches - were washed and then weighed in labs at the University, with the size of the studs also being measured.

The chemical characteristics of each block were then determined using an X-ray fluorescence (XRF) spectrometer, with the results used to confirm the age of individual pieces based on the presence of certain elements no longer in use.

By pairing those items with unweathered sets purchased in the 1970s and 80s, researchers were able to identify levels of wear and - as a result - how long the pieces might continue to endure in the marine environment.

The study was led by Dr Andrew Turner, Associate Professor (Reader) in Environmental Sciences, who has previously conducted extensive research into the chemical properties of items washed up as marine litter.

He said: "LEGO is one of the most popular children's toys in history and part of its appeal has always been its durability. It is specifically designed to be played with and handled, so it may not be especially surprising that despite potentially being in the sea for decades it isn't significantly worn down. However, the full extent of its durability was even a surprise to us.

"The pieces we tested had smoothed and discoloured, with some of the structures having fractured and fragmented, suggesting that as well as pieces remaining intact they might also break down into microplastics. It once again emphasises the importance of people disposing of used items properly to ensure they do not pose potential problems for the environment."

A clear majority of participants in a national survey about the zero-tolerance policy on the United States/Mexico border strongly opposed separating immigrant families and charging the parents as criminals, according to Baylor University research.

Researchers analyzed data from the Public Religion Research Institute's June 2018 Immigration Survey, which included questions about respondents' views on how to restrict or accommodate immigrants or refugees -- such as build a border wall or pass a law to prevent refugees from entering the United States.

The article is published in Analyses of Social Issues and Public Policy, a journal of The Society for the Psychological Study of Social Issues.

"Whether one favors or opposes the policy or implementation, research shows that parent-child separation is harmful to children and family systems," said lead author Wade C. Rowatt, Ph.D., Baylor University professor of psychology and neuroscience. "Previous research shows that immigrant children separated from their mothers in the same detention centers report more emotional problems than the detained children who were not separated. In addition, the prevalence of post-traumatic stress disorder among detained immigrant children was higher than the lifetime prevalence among United States adolescents."

Given those effects and the potential consequences for refugees, asylum seekers and their families, researchers sought to identify and better understand factors associated with support for, or opposition to, a zero-tolerance policy, Rowatt said.

The research included two studies. In the first, nearly three-fourths -- 73.3% -- of individuals opposed the policy. Participants from all 50 states numbered 1,018, ages 18 to 94, with 51% female, 64.6% white and 70.6% Christian. Political ideology was coded from 1 (very liberal) to 5 (very conservative).

Respondents were asked to indicate their level of agreement with "an immigration border policy that separates children from their parents and charges parents as criminals when they enter the country without permission." Respondents were divided along political lines, with 53% of Republicans favoring the policy and 90% of Democrats opposing it.

While age, gender and Christian religious affiliation were only weakly associated with support for separating immigrant families, researchers found that Christians did not oppose the policy of family separation as much as non-Christian religious individuals or irreligious individuals (atheists, agnostics and those with no religious affiliation).

In the second study, researchers analyzed data from two samples: 183 U.S. adults recruited from Amazon's Mechanical Turk, a crowdsourcing marketplace, and 144 undergraduate students at a private university in Central Texas. As with the first study, the majority opposed the family separation policy (62% of the college students, 70% of the MTurk sample), and conservative ideology was the strongest correlate among the minority who supported the policy.

The second study also found that variability in support for the policy was correlated consistently with social dominance orientation, which sees a majority group as superior to minority groups; conservative political ideology; and dehumanization -- viewing immigrants as less than fully human.

Researchers said more study is needed about attitudes toward immigrants to promote greater understanding and develop future policies.

Mysterious bone circles made from the remains of dozens of mammoths have revealed clues about how ancient communities survived Europe's ice age.

About 70 of these structures are known to exist in Ukraine and the west Russian Plain.

New analysis shows the bones at one site are more than 20,000 years old, making it the oldest such circular structure built by humans discovered in the region. The bones were likely sourced from animal graveyards, and the circle was then hidden by sediment and is now a foot below current surface level.

The majority of the bones found at the site investigated, in the Russian Plains, are from mammoths. A total of 51 lower jaws and 64 individual mammoth skulls were used to construct the walls of the 30ft by 30ft structure and scattered across its interior. Small numbers of reindeer, horse, bear, wolf, red fox and arctic fox bones were also found.

Archaeologists from the University of Exeter have also found for the first time the remains of charred wood and other soft non-woody plant remains within the circular structure, situated just outside the modern village of Kostenki, about 500km south of Moscow. This shows people were burning wood as well as bones for fuel, and the communities who lived there had learned where to forage for edible plants during the Ice Age. The plants could also have been used for poisons, medicines, string or fabric. More than 50 small charred seeds were also found - the remains of plants growing locally or possibly food remains from cooking and eating.

Dr Alexander Pryor, who led the study, said: "Kostenki 11 represents a rare example of Palaeolithic hunter-gatherers living on in this harsh environment. What might have brought ancient hunter gatherers to this site? One possibility is that the mammoths and humans could have come to the area on masse because it had a natural spring that would have provided unfrozen liquid water throughout the winter - rare in this period of extreme cold.

"These finds shed new light on the purpose of these mysterious sites. Archaeology is showing us more about how our ancestors survived in this desperately cold and hostile environment at the climax of the last ice age. Most other places at similar latitudes in Europe had been abandoned by this time, but these groups had managed to adapt to find food, shelter and water."

The last ice age, which swept northern Europe between 75-18,000 years ago, reached its coldest and most severe stage at around 23-18,000 years ago, just as the site at Kostenki 11 was being built. Climate reconstructions indicate at the time summers were short and cool and winters were long and cold, with temperatures around -20 degrees Celsius or colder. Most communities left the region, likely because of lack of prey to hunt and plant resources they depended upon for survival. Eventually the bone circles were also abandoned as the climate continued to get colder and more inhospitable.

Previously archaeologists have assumed that the circular mammoth bone structures were used as dwellings, occupied for many months at a time. The new study suggests this may not always have been the case as the intensity of activity at Kostenki 11 appears less than would be expected from a long term base camp site.

Other finds include more than 300 tiny stone and flint chips just a few millimetres in size, debris left behind the site's inhabitants as they knapped stone nodules into sharp tools with distinctive shapes used for tasks such as butchering animals and scraping hides.

The research, conducted by academics from the University of Exeter, University of Cambridge, Kostenki State Museum Preserve, University of Colorado Boulder and the University of Southampton, is published in the journal Antiquity.

A noblewoman from Imperial China enjoyed playing polo on donkeys so much she had her steeds buried with her so she could keep doing it in the afterlife, archaeologists found. This discovery by a team that includes Fiona Marshall, the James W. and Jean L. Davis Professor in Arts & Sciences at Washington University in St. Louis, is published March 17 in the journal Antiquity.

The research provides the first physical evidence of donkey polo in Imperial China, which previously was only known from historical texts. It also sheds light on the role for donkeys in the lives of high status women in that period.

Researchers found donkey bones in the tomb of Cui Shi, a noblewoman who died in 878 AD in Xi'an, China. The presence of work animals in a wealthy woman's tomb was unexpected, the researchers said.

"Donkeys were the first pack animal, the steam engines of their day in Africa and western Eurasia, but we know almost nothing about their use in eastern Asia," said Marshall, an archaeologist in the Department of Anthropology. She helped study the animal bones found in Cui Shi's tomb.

"Donkey skeletons just have not been found -- this is probably because they died along trade routes and were not preserved," she said. "The donkeys buried in the Tang Dynasty noble tomb in Xian provided a first opportunity -- and a very rare one -- to understand donkeys' roles in east Asian societies."

"There was no reason for a lady such as Cui Shi to use a donkey, let alone sacrifice it for her afterlife," said lead author Songmei Hu, from the Shaanxi Academy of Archaeology. "This is the first time such a burial has been found."

Polo is thought to have its origins in Iran; however, the sport flourished during the Tang Dynasty, which ruled China from AD 618 to 907. During this time, polo became a favorite sport of the royal and noble families, to the point where an emperor used a polo competition to pick generals. This included Cui Shi's husband, Bao Gao, who was promoted to general by Emperor Xizong for winning a match.

However, the sport was dangerous when played on large horses, with one emperor killed during a game. As such, some nobles preferred to play Lvju, or donkey polo. Although both forms of polo are mentioned in the historical literature, horse polo is the only form depicted in art and artifacts.

The researchers conducted radiocarbon dating and analyzed the size and patterns of stresses and strains on the donkey bones from Cui Shi's tomb. Their findings suggest that these small and active donkeys were being used for Lvju. Given that animals were typically included in burials for use in the afterlife, the donkeys' presence with Cui Shi allowed the researchers to conclude that she wanted to keep playing her favorite sport after death.

Taken together, this research provides the first physical evidence of donkeys being used by elite women and of donkey polo in Imperial China, the researchers said. As the first donkey skeletons from eastern Asia to be thoroughly studied, they also broaden the understanding of the role of donkeys in the past.