Earth

Life over the last half century has been pretty good for populations of Svalbard barnacle geese. A hunting ban implemented in the 1950s in their overwintering area in Scotland has led to explosive population growth -- from roughly 2800 birds in 1960 to more than 40000 birds today.

But what will happen to these birds and others like them, which migrate to Arctic nesting grounds, as the climate grows warmer?

You might think that a warmer climate in the Arctic would only be beneficial, but shorter winters with earlier springs -- as has already been recorded in places like Svalbard -- are not necessarily good for birds that migrate there.

Birds can arrive too late to match their breeding period with peak availability of their food. And that's just one possible issue raised by climate change. Another problem is that even when the birds can benefit from earlier springs, their predators can benefit from climate change, too.

Now, a team of researchers from Norway and the Netherlands has put together the puzzle of just how climate change affected a local Svalbard barnacle geese population. They've found that so far, climate change has been both good and bad for the birds -- with a net zero effect.

"When you consider the earlier springs, it's good news so far," says Kate Layton-Matthews, a PhD candidate at the Norwegian University of Science and Technology's (NTNU) Centre for Biodiversity Dynamics and the first author of the new study. "But the predation part outbalances the benefits from climate change."

3487 birds over 28 years

The researchers relied on data on from 3487 geese that have been collected since 1990 from Ny-Ålesund, a small town in the Svalbard archipelago.

Over that period, senior author Maarten J. J. E. Loonen at the University of Groningen in the Netherlands collected sightings and physical data from the birds -- their number of eggs, number of hatchlings and much more -- and also put rings on the birds' legs so they could be re-identified, year after year.

That wealth of information allows the researchers to be able to track overall population changes and to combine population data with other measurable variables, such as temperatures, time of snowmelt, start of growing season and the like. Co-author Eva Fuglei at the Norwegian Polar Institute also collected annual data on the abundance of the main predator, the Arctic fox.

"I have been studying this population for more than 30 years, and have seen increasing complexity in explaining population trends. Too many factors were changing at the same time, including climate change," Loonen said.

"The beauty for me in working with the team in Norway is that they could bring many of these factors together, especially related to climate change all along the flyway. The long data series from the Arctic is unique in its detail, but also the spatial scale on which these migratory birds operated and are affected by climate change."

In short, this huge complex dataset gives a detailed picture of the birds' lifecycles and how and why this has changed over the years, especially as the climate has warmed.

Warmer springs and winters are beneficial

The birds fly to Svalbard from their overwintering grounds in Solway Firth in Scotland. Many of the geese stop in Helgeland, a coastal area in northern Norway, before reaching their nesting grounds in the spring, while others make the flight direct from Scotland to Ny-Ålesund, a distance of 3000 kilometres.

Once on Svalbard, the birds can lay as many as six eggs on islands off Ny-Ålesund. When the goslings have hatched, the birds move inland into the tiny town, in search of more food for them and their young.

All of these different steps in their life cycle can be affected in both good and bad ways by climate change, Layton-Matthews says.

For example, earlier snow melt has so far increased production of eggs, and more of those eggs become goslings, because it has improved the availability of nest sites and food plants.

The researchers were more surprised to discover that the birds survived better when winters were mild in Scotland. If winters get milder in the future, which is expected due to global warming, the result can be that the overwintering populations continue to climb.

"Based on previous research I wasn't expecting to find these pretty large, positive effects from winter temperatures," she said, because the geese are fairly big and don't seem as if the winter cold should be a problem for them.

A cascade of effects

The benefit of the increased number of eggs and goslings due to warmer springs in Svalbard was also a benefit for the critters that prey on them, mainly Arctic foxes and polar bears. In fact, the healthier the goose population on Ny-Ålesund was, the more food there was for both of these animals, particularly for foxes.

Arctic fox numbers on Svalbard are partly linked to the number of reindeer, since they feed on the carcasses in winter and spring. In Svalbard as a whole, reindeer numbers have been increasing due to another effect of climate change: warmer, longer summers and "Arctic greening".

However, as documented by Brage Bremset Hansen, one of the paper's co-authors and Layton-Matthews's supervisor, reindeer populations can also suffer in winters with rain-on-snow events, which cause their grazing areas to be covered with an impenetrable layer of ice.

These kinds of winters are bad news for the reindeer, but good news for foxes, because it boosts cub production in the spring.

And the more Arctic foxes there are, the more they can devastate goose numbers, Layton-Matthews said. "The foxes mainly feed on the goslings," she said. "Which means that, even though gosling production increases with climate change, the net result is fewer adult geese recruited to the population."

"It's a real cascading effect," she said.

Managing goose populations for the future

Still, the huge increase in overwintering birds in Scotland and elsewhere in Europe has led to calls from farmers to regulate the goose populations, Layton-Matthews said. The overwintering geese can reduce the amount of grass or wheat in a field a lot, Layton-Matthews said.

The trouble is, there's little evidence that culling birds in Scotland will actually lead to reduced goose numbers, she said.

Culling overwintering birds in Scotland means the birds that haven't been culled will have more food to eat. The geese are also still colonizing new breeding areas in Svalbard which have come available due to the longer summer seasons, which open up new areas for an entire breeding cycle.

But if the production of young continues to be restricted by hungry foxes and polar bears, the net effect of all these changes may bring population numbers down, over time.
Over the last two years in the study area, there has been more and more predation on the geese by polar bears, which is similar to observed trends elsewhere, Loonen said.

"That means any management of Arctic-breeding geese needs to factor climate change into the plan", Layton-Matthews said.

"Future management plans to appease both the farming community and conservationists have to consider the potential for direct and indirect effects of climate change, all the way from the Arctic to Europe," she said.

Adults carrying a gene associated with a higher risk of Alzheimer's disease had a harder time accessing recently acquired knowledge, even though they didn't show any symptoms of memory problems, according to findings published in a joint Baycrest-University of Oxford study.

Researchers found that older adults carrying a specific strain of the gene, apolipoprotein E4, otherwise known as APOE4, weren't able to tap into information they had just learned to assist them on a listening test.

These findings suggest greater difficulty for these individuals to access knowledge from their memory to guide their attention in ways that would have improved their performance, according to the study published in the journal Scientific Reports. This work could lead to the development of new ways to detect individuals at risk.

The research team worked with 60 research participants (aged 40 to 61) from the Oxford Biobank who had varying combinations of APOE genes - which includes one group of individuals with a combination of APOE3/APOE4 genes, one group of individuals with a set of APOE4 genes and one group of individuals with a set of APOE3 genes. All research participants had normal hearing, scored within the normal range of cognitive assessments and completed a questionnaire about their memory.

Each research participant listened to 92 audio clips and they were told to pay attention to where the clip was coming from, whether it was presented in the left, right or both ears. After the clip was played, they were asked which side they heard the sound from and if they responded incorrectly, the sound was replayed. Participants had a one-hour break before hearing the 92 audio clips again, but this time they were asked whether there was an additional sound at the end of the clip and to press a button when they heard it. Each clip was placed twice. During the first play-through, the clip's location was replayed and during the second play-through, the additional tone was added.

The study found that no matter the APOE genotype, all older adults were able to learn the information and remember the location of the audio clip, but individuals with the APOE4 gene had greater difficulty in identifying the additional sound at the end of the clip.

"For some reason, people with the APOE4 gene were not able to take advantage of information they learned earlier, such as the expected location of the clip, to boost their performance," says Dr. Claude Alain, a senior author on the paper and senior scientist at Baycrest's Rotman Research Institute. "This study shows we have a test that is sensitive to capture problems or challenges faced by individuals with this gene, before their deficits are observed on a standard neuropsychological assessment."

This was an exciting study looking at healthy, middle-aged people who carry a gene that increases their risk of developing Alzheimer's disease by 15-fold, says Dr. Chris Butler, a senior author on the paper and an associate professor in clinical neurosciences at the University of Oxford.

"The research could lead to more sensitive methods of detecting Alzheimer's disease in its very earliest stages, the time at which treatments are most likely to be effective," says Dr. Butler. "I was delighted to carry out this work with researchers from Baycrest."

As next steps, researchers continue to explore how the brain's ability to process what is heard changes with neurodegenerative conditions, such as mild cognitive impairment.

Increasing atmospheric CO2 concentration is the leading cause of greenhouse effects and global warming. Notably, rapid climate warming can, in turn, either increase or decrease land carbon uptake, leading to negative or positive carbon cycle-climate change feedback, respectively.

Scientists previously did not understand what caused the direction of carbon-climate feedback, making it difficult to predict future climate warming.

Recently, however, a research group led by Dr. NIU Shuli from the Institute of Geographic Sciences and Natural Resources Research (IGSNRR) of the Chinese Academy of Sciences found that water availability in soil determines the direction of carbon-climate feedback. The group's findings were published in Science Advances on August 22, 2019.

The research team drew the conclusion primarily based on a field manipulation experiment in an alpine meadow on the Qinghai-Tibetan Plateau. They found that land carbon uptake increased when soil water content (SWC) was below its optimum but decreased above the optimum.

They revealed clear response surfaces showing how water availability determined the carbon cycle-climate warming feedback direction. Above optimum SWC, warming-induced decreases in SWC enhanced the direct warming effect of increasing soil temperature on land carbon uptake, leading to strong negative feedback.

However, below the optimum, warming-induced reduction in SWC dampened the direct warming effects on carbon uptake under moderately dry conditions and caused positive feedback under severe dry conditions.

"In addition, to test whether this water scaling pattern is generalizable across the ecosystem, we combined the site-level mechanism with a global synthesis. The results also show that warming stimulates net carbon uptake (negative feedback) under wet conditions but depresses it (positive feedback) under very dry conditions," said Prof. NIU.

The water scaling pattern revealed in this study provides compelling evidence that water regulates ecosystem feedback to climate warming at both temporal and spatial scales. It offers generalizable mechanisms that not only help explain varying magnitudes and directions of observed carbon-climate feedback but also improve model prediction of ecosystem carbon dynamics in response to climate warming.

Researchers from The Irish Longitudinal Study on Ageing (TILDA) at Trinity College Dublin have shown in the largest study to date that lower levels of specific dietary vitamins and antioxidants are associated with frailty.

Frailty is a common chronic syndrome which affects up to 25% of adults over 65 years and over half of adults over 80. Frailty is characterised by an overall decline in physical function and a loss of ability to bounce back after experiencing a stressful event such as infection, a fall or surgery. It is associated with poor health, disability and death. The TILDA study examined the association of vitamin B12, folate, vitamin D, lutein and zeaxanthin levels with frailty.

The B vitamins (B12 and folate) are important for several cellular processes throughout the body including DNA repair and energy metabolism. Vitamin D is essential for bone metabolism, muscle strength and mood. Lutein and zeaxanthin have antioxidant and anti-inflammatory properties important in eye health and brain health. Low levels of all of these vitamins and antioxidants is common among Irish adults.

In this new research lower levels of lutein, zeaxanthin, and vitamin D were consistently associated with not only frailty but also earlier stages of 'pre-frailty' (a subclinical precursor of frailty). Low levels of B vitamins were associated with pre-frailty. Furthermore, the accumulation of micronutrient insufficiencies - having low levels of more than one micronutrient - was progressively associated with severity stages of frailty.

This data raises the question of the role of dietary supplementation and contributes to the ongoing policy discussions regarding fortification.

Lead author of the study and Senior Research Fellow at TILDA, Dr Aisling O'Halloran, said: "We have presented evidence in the largest study to date that lower levels of specific vitamins and antioxidants - and having low levels of more than one micronutrient - is consistently and progressively associated with the most commonly used methods for measuring frailty. Our data suggest that low micronutrient status may act as an easily modified marker and intervention target for frailty among adults aged 50 years and over".

Principal Investigator of TILDA, Professor Rose-Anne Kenny said:

"Frailty occurs when a number of systems in the body lose reserve capacity and therefore the ability to 'bounce back' after even trivial illnesses. It is an important and challenging state; commonly associated with ageing but also common in patients of any age who have major surgery, cancer treatments and severe infections. The hall mark of frailty is muscle weakness. If it is recognised in its early stages, it can be reversed. However, the longer it is present, the more difficult is it to 'bounce back' and generalised weakness and fatigue become progressively worse. This research suggests new potential treatments for a common and important condition."

Co-author of the study Dr Eamon Laird said "Again we see that micronutrients (including vitamin D) are associated with better health outcomes in older adults. However we still lack a food fortification policy in Ireland and whilst this continues, we miss the opportunity of a cost-effective strategy to prevent and intervene in the progression of these conditions. As of yet there is no sign that the Irish government or the FSAI (Food Safety Authority Ireland) intend to advise or implement on such a strategy".

Ion beams are often used today in cancer treatment: this involves electrically charged atoms being fired at the tumour to destroy cancer cells. Although, it's not actually the ions themselves that cause the decisive damage. When ions penetrate through solid material, they can share part of their energy with many individual electrons, which then continue to move at relatively low speed - and it is precisely these electrons that then destroy the DNA of the cancer cells.

This mechanism is complex and not yet fully understood. Researchers at TU Wien have now been able to demonstrate that a previously little-observed effect actually plays a pivotal role in this context: owing to a process called interatomic Coulombic decay, an ion can pass on additional energy to surrounding atoms. This frees a huge number of electrons, with precisely the right amount of energy to cause optimal damage to the DNA of the cancer cells. In order to understand and further improve the particular effectiveness of ion therapy, this mechanism absolutely has to be taken into account. The results were recently published in the specialist publication Journal of Physical Chemistry Letters.

One fast particle - or lots of slow ones

When a charged particle penetrates a material at great speed - such as human tissue - it leaves a giant atomic mess in its wake: "This can trigger a whole cascade of effects," says Janine Schwestka, lead author of the recent publication, who is currently working on her dissertation in the team led by Prof. Friedrich Aumayr and Dr Richard Wilhelm. When the ion moves through other atoms, these and other particles can become ionised, fast electrons fly around and then collide with other particles. Ultimately, a fast, charged ion can trigger a particle shower of hundreds of electrons each with much lower energy.

In everyday life, we are used to fast objects having more dramatic effects than slower ones - a football kicked with full force causes much more damage in a china shop than one that is gently rolled in. At an atomic level, however, this does not apply: "The likelihood of a slow electron destroying a DNA strand is much greater. Conversely, an extremely fast electron normally just flies right past the DNA molecule without leaving a trace," explains Janine Schwestka.

From one electron shell to another

The team from TU Wien recently took a closer look at an extremely special effect - namely, interatomic Coulombic decay. "The ion's electrons can assume different states. Depending on how much energy they have, they can be located in one of the inner shells, close to the nucleus, or in an outer shell," says Janine Schwestka. Not all possible electron spaces are occupied. If an electron shell in the medium energy range is free, an electron can then cross over to there from a shell with higher energy. This releases energy, which can then be passed to the material via interatomic Coulombic decay: "The ion transfers this energy to several atoms in the direct vicinity at the same time. One electron is detached from each of these atoms but because the energy is divided among several atoms we are talking about lots of really slow electrons," explains Schwestka.

Xenon and graphene

With the help of an ingenious experimental setup, it has now been possible to prove the efficacy of this process. Multiply charged xenon ions are shot at a graphene layer. Electrons from the outer xenon shells switch to a position in another shell with less energy, causing electrons to be detached from numerous carbon atoms in the graphene layer, which are then recorded by a detector, so as to measure their energy. "In fact, in this way, we were able to show that interatomic Coulombic decay plays a vital role in generating a large number of free electrons in the material," says Prof. Friedrich Aumayr.

In order to correctly describe the interaction of ion beams with solid materials or organic tissues, this effect absolutely must be taken into account. This is important, on one hand, for optimising ion beam therapies for treating cancer, but also for other important areas, such as protecting the health of space station crews, where you are exposed to constant particle bombardment from cosmic radiation.

Clear evidence that higher levels of physical activity - regardless of intensity - are associated with a lower risk of early death in middle aged and older people, is published by The BMJ today.

The findings also show that being sedentary, for example sitting still, for 9.5 hours or more a day (excluding sleeping time) is associated with an increased risk of death.

Previous studies have repeatedly suggested that sedentary behaviour is bad and physical activity is good for health and long life.

Guidelines recommend at least 150 minutes of moderate intensity or 75 minutes of vigorous physical activity each week, but are based mainly on self reported activity, which is often imprecise. So exactly how much activity (and at what intensity) is needed to protect health remains unclear.

To explore this further, researchers led by Professor Ulf Ekelund at the Norwegian School of Sport Sciences in Oslo analysed observational studies assessing physical activity and sedentary time with death ("all cause mortality").

Studies used accelerometers (a wearable device that tracks the volume and intensity of activity during waking hours) to measure total activity in counts per minute (cpm) of wear time. Intensity is usually separated into light, moderate and vigorous - and the time in these intensities is then estimated.

Examples of light intensity activity includes walking slowly or light tasks such as cooking or washing dishes. Moderate activity includes brisk walking, vacuuming or mowing the lawn, while vigorous activity includes jogging, carrying heavy loads or digging.

Data from eight high quality studies involving 36,383 adults aged at least 40 years (average age 62) were included. Activity levels were categorised into quarters, from least to most active, and participants were tracked for an average of 5.8 years.

During follow-up, 2149 (5.9%) participants died. After adjusting for potentially influential factors, the researchers found that any level of physical activity, regardless of intensity, was associated with a substantially lower risk of death.

Deaths fell steeply as total activity increased up to a plateau at 300 cpm, similar to the average activity levels in a population-based sample of US men and about 10-15% lower than that observed in Scandinavian men and women.

A similarly steep decrease in deaths occurred with increasing duration of light physical activity up to a plateau of about 300 minutes (5 hours) per day and of moderate intensity physical activity of about 24 minutes per day.

The largest reduction in risk of death (about 60-70%) was between the first quarter (least active) and the fourth quarter (most active), with approximately five times more deaths in those being inactive compared with those most active. This strengthens the view that any physical activity is beneficial and likely achievable for large segments of the population say the researchers.

In contrast, spending 9.5 hours or more each day sedentary was associated with a statistically significant increased risk of death.

The researchers point to some limitations. For example, all studies were conducted in the US and western Europe, and included adults who were at least 40 years old, so findings may not apply to other populations or to younger people.

Nevertheless, they say the large sample size and device based measures of sedentary time and physical activity provide more precise results than previous studies.

As such, they say their results provide important data for informing public health recommendations, and suggest that the public health message might simply be "sit less and move more and more often."

These findings are important and easy to interpret, say researchers in a linked editorial. However, questions remain, particularly over whether the effect of physical activity continues above a certain threshold.

They acknowledge that increasing activity at the population level is challenging, but say walking is one promising target for intervention, as it is simple, affordable (free), achievable even for older adults, and rarely contraindicated.

"Developing ways to limit sedentary time and increase activity at any level could considerably improve health and reduce mortality," they conclude.

A multi-national team of researchers, including authors from the National Institute for Health Research (NIHR) Leicester Biomedical Research Centre (BRC), have produced clear evidence that higher levels of physical activity - regardless of intensity - are associated with a lower risk of early death in middle aged and older people.

The findings, published in The BMJ today, also show that being sedentary, for example sitting, for 9.5 hours or more a day (excluding sleeping time) is associated with an increased risk of death.

The World Health Organisation guidelines recommend at least 150 minutes of moderate intensity or 75 minutes of vigorous physical activity each week for adults aged between 18 and 64 years. However, these are based mainly on self-reported activity, which is often imprecise. So exactly how much activity (and at what intensity) is needed to protect health remains unclear.

To explore this further, researchers led by Professor Ulf Ekelund at the Norwegian School of Sport Sciences in Oslo analysed observational studies assessing physical activity and sedentary time with death ("all-cause mortality").

Studies included in the research used accelerometers (a wearable device that tracks the volume and intensity of activity during waking hours) to objectively measure daily activity levels.

Examples of light intensity activity include walking slowly or light tasks such as cooking or washing dishes. Moderate activity includes include any activities that make you breath harder, such as brisk walking.

Data from eight high quality studies, including one funded by the NIHR Collaboration for Leadership in Applied Health Research and Care (CLAHRC) East Midlands, involved 36,383 adults aged at least 40 years (average age 62) were used in the analysis. Activity levels were categorised into quarters, from least to most active, and participants were tracked for an average of 5.8 years.

During follow-up, 2,149 (5.9 per cent) participants died. After adjusting for potentially influential factors, the researchers found that any level of physical activity, regardless of intensity, was associated with a substantially lower risk of death.

Deaths fell steeply as total volume of physical activity increased up to a plateau of about 300 minutes (5 hours) per day of light-intensity physical activity or about 24 minutes per day moderate intensity physical activity. At these levels the risk of death was halved compared to those engaging in little or no physical activity.

Professor Tom Yates, a professor of physical activity, sedentary behaviour and health at the University of Leicester and a co-author of the study, said: "These results are fantastic. It has previously been widely assumed that more is better in terms of physical activity for health. However, this study suggests health may be optimised with just 24 minutes per day of brisk walking or other forms of moderate-intensity physical activity.

"Another important finding was that spending 9.5 hours or more each day sedentary - which essentially means sitting was associated with a statistically significant increased risk of death, with each hour more above this threshold increasing the risk of death further. This highlights the importance of avoiding spending most of the day sitting, as well undertaking purposeful physical activity."

The researchers point to some limitations. For example, all studies were conducted in the US and western Europe, and included adults who were at least 40 years old, so findings may not apply to other populations or to younger people.

Nevertheless, they say the large sample size and device based measures of sedentary time and physical activity provide more precise results than previous studies.

Dr Charlotte Edwardson, an associate professor in physical activity, sedentary behaviour and health at the University of Leicester and a co-author of the study, said: "These findings really reinforce the saying 'Doing something is better than doing nothing'. They show that physical activity of ANY intensity lowers the risk of death, so if you're someone who doesn't achieve the recommended levels of moderate intensity physical activity, then doing more light activity, for example, pottering around more at work or at home and just generally being on your feet more, will still be beneficial.

"Also, a large risk reduction was seen between the least and the second least active group suggesting that incorporating some time doing physical activity, light or moderate intensity, in daily life is associated with a big health benefit. For example, the difference between the least and second least active groups was about 60 mins of light activity and 5 mins of moderate activity.

"Our results provide important data for informing public health recommendations, and suggest that the public health message might simply be "sit less, move more and more often"."

In a linked editorial in The BMJ, independent researchers acknowledged the importance of the findings, concluding that, "developing ways to limit sedentary time and increase activity at any level could considerably improve health and reduce mortality."

Toxoplasma gondii is a microbial parasite that infect humans and complete its full life cycle only in cats. New research published August 20 in the open-access journal PLOS Biology shows why: the sexual phase of the parasite's life cycle requires linoleic acid, a nutrient/lipid found at uniquely high levels in the felines, because cats lack a key enzyme for breaking it down. The finding, from by Bruno Martorelli Di Genova and Laura Knoll of the University of Wisconsin-Madison and colleagues, is likely to help in the development of treatments to reduce spread of the parasite from cats to their human companions. Also, presents an opportunity to avoid using cats for Toxoplasma research.

Toxoplasma can live asexually in any mammal, including humans. But it forms gametes (sexual cells) only in cats, a restriction that has long been recognized, but whose reason was not understood. The authors suspected something was missing when reproducing the infections in vitro and not observing sexual development. It is known that fungi require linoleic acid for sexual development. To test Toxoplasma's requirement for the same lipid, they generated cat intestinal organoids--three-dimensional "test tube" models that share several essential properties with actual intestines--and showed that linoleic acid was required for sexual reproduction of the parasite. Cats lack an enzyme called delta-6-desaturase, which catalyzes the conversion of linoleic acid to arachidonic acid, accounting for the peculiarly high levels of linoleic acid in the cat intestine, but not in other mammals. When the authors supplemented the diet of mice with linoleic acid, and added a specific inhibitor of the enzyme, Toxoplasma could complete the sexual phase of its life cycle in the mouse intestine.

Toxoplasma is the leading cause of foodborne illness in the US, according to CDC. The most common route of infection for human is by consumption of contaminated raw or undercooked meat. Cat litter, after 24-48 of being cleaned, can also a source of Toxoplasma infection. However, cats can only shed oocysts once in their life time. Pregnant women are urged to avoid eating raw or undercooked meat, as also avoiding cleaning the litterbox after 48 hours, to prevent Toxoplasma infection. Congenital toxoplasmosis can have potentially serious consequences for the unborn child. An improved understanding of the parasite life cycle stemming from this study may lead to production of vaccines that could inhibit Toxoplasma's sexual reproduction or the transmission of Toxoplasma to livestock.

As medicine becomes both bigger and more personalized, the need for massive databases of patient records, such as the 1 million person All of Us Research Program, become increasingly essential to fueling both new discoveries and translational treatments.

But the looming, lingering question is to what degree are individual patients willing to share medical records and biospecimens with researchers and institutions beyond their personal physician or health care system? And more specifically, how should patients be asked and what information are they most likely to share?

In a novel attempt to answer these questions, researchers at University of California San Diego School of Medicine, with collaborators in California, North Carolina and Texas, asked patients at two academic hospitals to respond to a variety of different approaches seeking to share their medical data with other researchers.

The findings are published in the August 21, 2019 online issue of JAMA Network Open.

The survey was conducted at two academic hospitals -- UC San Diego Health and UC Irvine Health between May 1, 2017 and September 31, 2018. Participants were randomly selected to one of four options with different layouts and formats for indicating sharing preferences: opt-in simple, opt-in detailed, opt-out simple and opt-out detailed. In the simple forms, there were 18 categories where participants could choose to share information; in the detailed forms, there were 59 items. The items ranged from demographics like age, sex and race and socioeconomic status to lab results (genetic tests, drug screening, etc.), imaging (x-rays, MRI) and biospecimens (blood, urine, tissue).

Participants were also asked to what degree they would be willing to share their medical data: with researchers only in the same health care organization or with those working at other nonprofit or for-profit institutions.

Among 1,800 eligible participants, 1,246 completed the data sharing survey and were included in the analysis and 850 responded to a satisfaction survey. Slightly less than 60 percent were female and slightly less than 80 percent were white. The mean age was 51 years old.

More than 67 percent of survey participants indicated they would share all items with researchers from the home institution (which patients presumably already trust with their health care), with progressively smaller percentages for sharing with other nonprofit institutions or with other for-profit institutions. Many of the respondents indicated that they were only unwilling to share a few items.

"These results are important because data from a single institution is often insufficient to achieve statistical significance in research findings," said the study's senior author, Lucila Ohno-Machado, MD, PhD, professor of medicine, associate dean for informatics and technology in the UC San Diego School of Medicine and chair of the Department of Biomedical Informatics at UC San Diego Health. "When sample sizes are small, it is unclear whether the research findings generalize to a larger population. Additionally, in alignment with the concept of personalized medicine, it is important to see whether it is possible to personalize privacy settings for sharing clinical data."

Generally speaking, the current state of affairs concerning the sharing of "anonymized" patient health data for secondary research is uneven and unsettled. It has been shown that anonymization methods -- in which data sets are either encrypted or stripped of personally identifiable information -- are not 100 percent effective. Since 2013, newly enrolled patients are required to proactively consent to sharing their personal health information for research studies or future secondary use. In California, a patient's specific permission is required to share mental health, substance abuse, HIV status and genetic information, but other items or conditions are not specified. In many states, there is no requirement for a patient's specific permission on these types of items before they can be shared. Today, for practical purposes, patients have the option to decline any part of their medical record be used for research. They cannot indicate what types of research or researcher should be able to obtain their records.

Almost three-quarters of respondents -- 67.1 percent -- said they would be willing to share all items with researchers from their health care institutions; almost one-quarter said they would be willing to share all items with all interested researchers, a finding the authors said was reassuring and could help in the planning of studies based on EHRs and biospecimens that would be expected to be broadly shared.

Equally encouraging: Less than 4 percent of participants said they were not willing to share any information with anyone.

Ohno-Machado said the way in which preferences are elicited also has an influence. There was greater sharing per item when respondents were asked to opt-out than when they were asked to opt-in. Whether the form had details about the items or used broad categories did not have an influence on sharing.

"This is important because a simple form could be used in the future to elicit choices from all patients, saving their time without significantly affecting their privacy preferences," said Ohno-Machado. "However, different rates of sharing are expected for opt-in and opt-out of sharing clinical records for research."

A key finding was that a majority of survey participants identified at least one item that they did not want to share with a particular type of researcher (for example, a scientist at another for-profit institution), though they were willing to share other items.

"This finding is important," wrote the authors, "because the item to withhold may not be of relevance to a certain study, but the current all-or-nothing option, if chosen, would remove that patient's data from all research studies."

The authors said the survey's tiered-permission system that allows specific removal of data items or categories proves both doable and appealing to patients, in part because there are differences among individuals in where and with whom they share what.

The findings, said the authors, trigger further questions about the ideal balance between giving patients the ability to choose what portions of their data they want to share for research and with whom and the "greater good," i.e., how fast research can be accelerated for the benefit of all.

"Institutions currently make decisions on sharing on behalf of all patients who do not explicitly decline sharing. It is possible that asking patients directly would increase the amount of data shared for research. On the other hand, it is also possible that some types of research would suffer from small sample sizes if patients consistently decline certain categories of items," Ohno-Machado said.

In a large survey in sub-Saharan Africa, adults who said they had paid a bribe for healthcare in the past year were more than four times as likely to report difficulty in obtaining care than those who had not paid bribes. Amber Hsiao and colleagues at the Technical University of Berlin, Germany, report these findings in the open-access journal PLOS ONE on August 21, 2019.

Previous research has explored how institutional corruption--in which healthcare funds are misappropriated or pocketed by officials--harms health outcomes in Africa. Bribery is a different form of corruption in which an individual must pay a bribe in order to receive healthcare, potentially discouraging them from seeking care or sowing distrust in the medical system. However, the extent to which bribery limits healthcare access has been unclear.

To better understand the effects of bribery in healthcare, Hsiao and colleagues analyzed data from a 2014¬-2015 survey of adults in 32 sub-Saharan African countries. Of 31,322 adults who had received medical care in the year the survey was conducted, 14 percent said they had engaged in bribery to obtain care at least once in the past year.

Controlling for individual and regional factors, survey respondents who had paid one or two bribes were 4.11 times more likely to report difficulties in obtaining care than those who had paid no bribes. Respondents who reported paying bribes "often" were nine times more likely to say they had difficulty accessing care.

These results suggest that bribery poses serious challenges to accessing medical care in sub-Saharan Africa. The findings could help inform efforts of policymakers and researchers as they work toward the United Nations' goal of universal health coverage by 2030.
The authors suggest that future research could focus on individual countries to identify potential strategies for reducing bribery. They also call for increased efforts to combat corruption in healthcare.

Amber Hsiao summarizes: "When patients in sub-Saharan Africa have to pay bribes for healthcare, they are much more likely to report difficulties in obtaining medical care. Bribery at the point of care and its implications need to be better monitored and addressed in the quest to reach universal health coverage."

Migration patterns in present-day Denmark shifted at the beginning of the Nordic Bronze Age, according to a study published August 21, 2019 in the open-access journal PLOS ONE by Karin Frei of the National Museum of Denmark and colleagues. Migrants appear to have come from varied and potentially distant locations during a period of unprecedented economic growth in southern Scandinavia in the 2nd millennium BC.

The 2nd and 3rd millennia BC are known to have been a period of significant migrations in western Europe, including the movement of steppe populations into more temperate regions. Starting around 1600 BC, southern Scandinavia became closely linked to long-distance metal trade elsewhere in Europe, which gave rise to a Nordic Bronze Age and a period of significant wealth in the region of present-day Denmark.

In this study, Frei and colleagues investigated whether patterns of migration changed during this Nordic Bronze Age. They examined skeletal remains of 88 individuals from 37 localities across present-day Denmark. Since strontium isotopes in tooth enamel can record geographic signatures from an early age, analysis of such isotopes was used to determine individuals' regions of provenance. Radiocarbon dating was used to determine the age of each skeleton and physical anthropological analyses were also conducted to add information on sex, age and potential injuries or illness.

From c. 1600 BC onwards, around the beginning of the Nordic Bronze Age, the geographic signal of migrants became more varied, an indication that this period of economic growth attracted migrants from a wide variety of foreign locales, possibly including more distant regions. The authors suggest this might reflect the establishment of new cultural alliances as southern Scandinavia flourished economically. They propose that further study using ancient DNA may further elucidate such social dynamics at large scales.

Co-author Kristian Kristiansen notes: "Around 1600 BC, the amount of metal coming into southern Scandinavia increased dramatically, arriving mostly from the Italian Alps, whereas tin came from Cornwall in south England. Our results support the development of highly international trade, a forerunner for the Viking Age period."

Karin Frei adds: "Our data indicates a clear shift in human mobility at the breakthrough point of the Nordic Bronze Age, when an unprecedented rich period in southern Scandinavia emerged. This suggests to us that these aspects might have been closely related."

Almost one-third of people migrating to the US via Mexico experience physical, psychological, and/or sexual violence along the way, according to a study published August 21, 2019 in the open-access journal PLOS ONE by René Leyva-Flores and Cesar Infante from the National Institute of Public Health (Mexico), Juan Pablo Gutierrez from the National Autonomous University of Mexico, and colleagues.

In recent years, multiple studies have shown that traditional migration routes have become more dangerous around the world. As part of a research collaboration with the migrant shelter group Casas del migrante, the authors and Casas del migrante staff surveyed 12,023 migrants in transit through Mexico to the US between 2009 and 2015. They collected information from these migrants, who stayed at one of five Casas del migrante shelters in Mexico, about any violence they'd experienced en route as well as gathering demographic data. 58 of the migrants also participated in longer interviews, and the authors performed statistical and descriptive analyses on their transcripts.

The researchers found that almost 30 percent of the surveyed migrants had experienced some form of violence. More specifically, 24 percent reported physical violence, 19 percent reported psychological violence, and approximately 2 percent reported sexual violence. Transgender, transsexual and transvestite migrants experienced a significantly greater burden of overall violence compared to men and women, and both this group and women experienced a significantly greater burden of sexual violence compared to men. Violence was experienced more frequently by migrants from Central American countries (30.6 percent) and other countries (40.0 percent) than by Mexican migrants (20.5 percent).

The researchers note that many violent incidents are not reported because victims in Central America and Mexico may have normalized violence and because many migrants don't trust authorities enough to reveal their experiences. Nonetheless, this study underscores that migrants are subjected to high levels of violence while journeying to the US, with gender and nationality significantly affecting the amount and type of violence migrants face. The authors stress that protective measures are urgently needed to ensure migrants' human rights.

Dr Infante notes: "Migrants are subjected to a high level of violence while in transit to the US. Those traveling under irregular migratory conditions are targets of even greater violence, a condition exacerbated by gender inequality. Protective measures regarding access to health care and legal services are urgently needed to ensure the human rights of these populations."

Scientists may have uncovered how sea-surface temperature patterns influence the number, strength and distributions of April tornado formation in the south-central region of the United States known as "Tornado Alley." Their results underscore how shifting climate patterns potentially affect tornado formation within seasons, which could help reduce fatalities and widespread property loss during peak tornado months - by facilitating improved predictions. In 2011, nearly 1,700 tornadoes were recorded in North America, resulting in more than 500 deaths and $10 billion in property and crop damage. The subsequent tornado season, in 2012, saw an estimated 900 tornadoes and 70 deaths. Seeking to better understand the potential causes underlying such year-to-year variations, J.-E. Chu et al. conducted a month-by-month analysis of tornado counts across North America spanning 1954 to 2016, with a focus on the springtime Tornado Alley twisters. The researchers found no significant connection between May tornado numbers and sea surface temperature patterns. This observation hints that tornadoes occurring in May are more strongly influenced by internal atmospheric processes. In contrast, they discovered that April tornado activity is strongly influenced by large-scale climate patterns. For example, the April tornados were more frequent when equatorial Pacific and eastern North Pacific waters were cooler and subtropical Pacific and western Atlantic waters were warmer. Based on these results, Chu and colleagues' findings suggest that shifting weather patterns within seasons--rather than seasonal averages alone--are important factors to consider in studies that measure the impact of climate change on tornado frequencies.

The majority of soft robots today rely on external power and control, keeping them tethered to off-board systems or rigged with hard components. Now, researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and Caltech have developed soft robotic systems, inspired by origami, that can move and change shape in response to external stimuli, paving the way for fully untethered soft robots.

The research is published in Science Robotics.

"The ability to integrate active materials within 3D-printed objects enables the design and fabrication of entirely new classes of soft robotic matter," said Jennifer A. Lewis, the Hansjorg Wyss Professor of Biologically Inspired Engineering at SEAS and co-lead author of the study.

The researchers turned to origami to create multifunctional soft robots. Through sequential folds, origami can encode multiple shapes and functionalities in a single structure. Using materials known as liquid crystal elastomers that change shape when exposed to heat, the research team 3D-printed two types of soft hinges that fold at different temperatures and thus can be programmed to fold in a specific order.

"With our method of 3D printing active hinges, we have full programmability over temperature response, the amount of torque the hinges can exert, their bending angle, and fold orientation. Our fabrication method facilitates integrating these active components with other materials," said Arda Kotikian, a graduate student at SEAS and the Graduate School of Arts and Sciences and co-first author of the paper.

"Using hinges makes it easier to program robotic functions and control how a robot will change shape. Instead of having the entire body of a soft robot deform in ways that can be difficult to predict, you only need to program how a few small regions of your structure will respond to changes in temperature," said Connor McMahan, a graduate student at Caltech and co-first author of the paper.

To demonstrate this method, Kotikian, McMahan, and the team built several soft devices, including an untethered soft robot nicknamed the "Rollbot." The Rollbot begins as a flat sheet, about 8 centimeters long and 4 centimeters wide. When placed on a hot surface, about 200°C, one set of hinges folds and the robot curls into a pentagonal wheel.

Another set of hinges is embedded on each of the five sides of the wheel. A hinge folds when in contact with the hot surface, propelling the wheel to turn to the next side, where the next hinge folds. As they roll off the hot surface, the hinges unfold and are ready for the next cycle.

"Many existing soft robots require a tether to external power and control systems or are limited by the amount of force they can exert. These active hinges are useful because they allow soft robots to operate in environments where tethers are impractical and to lift objects many times heavier than the hinges," said McMahan.

Another device, when placed in a hot environment, can fold into a compact folded shape resembling a paper clip and unfold itself when cooled.

"These untethered structures can be passively controlled," said Kotikian. "In other words, all we need to do is expose the structures to specific temperature environments and they will respond according to how we programmed the hinges."

While this research only focused on temperature responses, liquid crystal elastomers can also be programmed to respond to light, pH, humidity and other external stimuli.

"This works demonstrates how the combination of responsive polymers in an architected composite can lead to materials with self-actuation in response to different stimuli. In the future, such materials can be programmed to perform ever more complex tasks, blurring the boundaries between materials and robots," said Chiara Daraio, Professor of Mechanical Engineering and Applied Physics at Caltech and co-lead author of the study.

Increasingly frequent and severe forest fires could burn generations-old carbon stored in the soils of boreal forests, according to results from the Arctic-Boreal Vulnerability Experiment (ABoVE) funded by NASA's Earth Science Division. Releasing this previously buried carbon into the atmosphere could change these forests' balance of carbon gain and loss, potentially accelerating warming.

Canada's Northwest Territories were scorched by record-breaking wildfires in 2014. The team of researchers from the United States and Canada took soil samples from more than 200 locations in the region. They found that for old forests (more than 70 years old) and forests in wet locations, a thick layer of organic matter in the soil protected the oldest carbon, called "legacy carbon," that was not burned in previous cycles of burn and regrowth. However, in younger, drier forests, the shallower soil organic matter layer allowed fires to reach the legacy carbon, releasing it into the atmosphere.

As Earth's northern regions grow warmer and drier due to climate change, fire seasons are getting longer and fires are becoming more severe. Boreal forests have long been thought to absorb more carbon from the atmosphere than they release into it, making them carbon "sinks." But if bigger and more frequent fires start burning legacy carbon, these forests could start releasing more carbon than they store. Carbon dioxide is a greenhouse gas, so releasing more of it into the atmosphere could affect the balance of the global carbon cycle and contribute to climate change

Boreal forests are located in the northernmost regions of North America, Europe and Canada, and contain spruce, fir, pine, larch, aspen and birch trees. These forests store 30%-40% of all land-based carbon in the world, and most of that carbon is found in the soils. Soil-based carbon includes soil microbes; plant material made up of dead leaves, branches and stems; and both living and dead roots, as well as burned material from previous fires.

During intense fires, the organic material that contains the soil carbon can burn along with trees and plants. Older carbon deeper in the soil does not always burn in a fire, but can stay protected in the soil. The researchers called this "legacy carbon."

After observing the intensity of the 2014 fires, the team wondered if these pools of legacy carbon were at risk.

"Carbon accumulates in these soils like tree rings, with the newest carbon at the surface and the oldest carbon at the bottom," said senior author Michelle Mack, a professor at Northern Arizona University's Center for Ecosystem Science and Society. "We thought we could use this layering to see how far back in time, in the history of the forest, fires were burning."

The team measured the age of the trees, how deep in the soil the fire burned, how moist the sampled area was, and the depth of the topmost soil organic layer, composed of plant and animal matter. They also used radiocarbon dating of the soils to determine if the legacy carbon pools burned in the fire.

The team found that wetter forests and those less than 60 years old were more likely to contain legacy carbon than older, drier forests. But the ones most likely to lose that legacy carbon were the young forests in drier areas. These forests were less likely to have accumulated enough organic matter to protect the older carbon between previous fires and the 2014 fire. Almost half of the plots under 60 years old lost legacy carbon, while just one older plot did.

In total, about 12% of the forests that burned in the 2014 fires met the criteria for being vulnerable to legacy carbon loss. The researchers estimate that these forests released about 8.8 million tons of carbon as they burned, compared to the nearly 104 million tons released by all the fires.

The team said their results show that in order to understand the effects of future fires on Canada's boreal forests and the global carbon cycle, researchers must account for legacy carbon loss.

"By defining and analyzing 'legacy carbon,' this paper offers a new way to think about long-sequestered carbon stocks in boreal forests and how vulnerable they are to being burned during increasingly frequent and severe wildfires," said Brendan Rogers, a scientist at Woods Hole Research Center who co-authored the Nature study. "This tool helps us understand when burning goes 'outside the norm' from a historical perspective and begins to combust carbon stocks that survived past fires."

If wildfires do become more frequent, they could increase the number of young forests vulnerable to burning and legacy carbon loss, they added.

"In older stands that burn, legacy carbon is protected by thick organic soils," said Xanthe Walker, lead author and postdoctoral researcher at the Center for Ecosystem Science and Society at Northern Arizona University. "But in younger stands that burn, the soil does not have time to re-accumulate after the previous fire, making legacy carbon vulnerable to burning. This pattern could shift boreal forests into a new domain of carbon cycling, where they become a carbon source instead of a sink."