Culture

An international research team led by scientists from Estonian University of Life Sciences has for the first time sequenced and assembled the genome of the wels catfish (Silurus glanis). The maximum reported size of the wels catfish is 5 m and up to 300 kg, which makes it one of the largest freshwater fish species in the whole world. By deciphering the genetic code of the barbelled giant, scientists expect to better understand the secrets of the wels catfish's exceptionally rapid growth, enormous appetite and longevity.

The wels catfish lives in large European rivers and lakes. Catfish is hunting mainly at night and is not a picky eater, with invertebrates, fish, frogs, rodents and birds in its regular diet. When the water is warm and food is plentiful, the catfish grows extremely rapidly: ten-year-old fish can reach one and a half metres length. Given that a catfish can live up to 80 years, it is no wonder it has rightly become the prized trophy fish and a central character in many legends among anglers.

Due to its rapid growth and tender, boneless flesh, the catfish is increasingly gaining popularity for recreational fishing and aquaculture. The greatest number of wels catfish are being caught from the inland waters of Russia, Kazakhstan and Turkey, and its aquaculture production is currently approximately 2000 tonnes per year. At the same time, the lack of genetic information in wels catfish has inhibited application of modern selective breeding methods that utilize genomic information instead of phenotypic traits to estimate the breeding values of fish. "Assembled wels catfish genome allows researchers to find genomic regions and gene variants that impact growth rate, age at sexual maturity, disease resistance and other relevant traits for aquaculture," explained Riho Gross, Chair professor of Aquaculture at Estonian University of Life Sciences, who led the research.

According to Anti Vasemägi, senior researcher of Estonian University of Life Sciences and professor of Swedish University of Agricultural Sciences, who participated in the work, the size of wels catfish genome can be compared to that of other bony fishes (800 million base pairs), and contains a little more than 21 000 genes. He added that the genome assembly will serve as a springboard for future research aimed at addressing the bottlenecks in catfish aquaculture and challenges linked to conservation of wild populations.

The toughest organisms on Earth, called extremophiles, can survive extreme conditions like extreme dryness (desiccation), extreme cold, space vacuum, acid, or even high-level radiation. So far, the toughest of all seems to be the bacterium Deinococcus radiodurans - able to survive doses of radiation a thousand times greater than those fatal to humans. But to this date, scientists remained puzzled by how radio-resistance could have evolved in several organisms on our planet, naturally protected from solar radiation by its magnetic field. While some scientists suggest that radio-resistance in extremophile organisms could have evolved along with other kinds of resistance, such as resistance to desiccation, a question remained: which genes are specifically involved in radio-resistance?

To address this question, the team of Dr. Cox, at the University of Wisconsin-Madison, decided to "let the cells tell them". The researchers started with the naturally non-resistant bacteria, E. coli, and exposed it to iterative cycles of high-level irradiation. After many rounds of radiation exposure and outgrowth, a few radio-resistant populations emerged. Using whole-genome sequencing, the researchers studied the genetic alterations present in each radio-resistant population and determined which mutation provided radio-resistance to the bacteria.

In their first study, the team of Dr. Cox started by exposing E. coli to 50 rounds of ionization (Bruckbauer et al 2019b). After about 10 rounds, some radio-resistant populations emerged, and after 50, the study of their genetic profile highlighted three mutations responsible for radio-resistance - all in genes linked to DNA repair mechanisms. Here, in their new study, the team exposed the bacteria to 50 more rounds of radiation exposure and selection.

The results published in Frontiers in Microbiology show that the populations of radioresistant E. coli, continued to evolve and sub-populations emerged. Surprisingly, while radio-resistance induced by the first series of ionization could mainly be associated with three mutations, the second induced hundreds of mutations including large deletions and duplications of several genes. "The four populations we are evolving in this new trial have now achieved levels of radio-resistance that are approaching the levels seen with Deinococcus radiodurans. As the current trial has progressed, the genomic alterations have proven to be much more complex than anticipated." Dr. Cox says.

Although it is harder to pinpoint all the mutations contributing to the increase of radio-resistance this time around, the researchers show that more cellular metabolisms are affected (ATP synthesis, iron-sulfur cluster biogenesis, cadaverine synthesis, and reactive oxygen species response). Furthermore, this study proves that radio-resistance can develop to the level of Deinococcus radiodurans, independently to desiccation-resistance. As the exposition to radiation and experimental evolution continues, more data are gathered on how to induce radio-resistance in bacteria. This could one day constitute a precious toolbox of mutations to engineer radioresistant probiotics helping for example patients treated with radiotherapy, or astronauts exposed to space radiation.

BATON ROUGE, Louisiana – More than 18 percent of U.S. adults do not know whether they will have enough to eat from day to day, and the numbers are worse for Hispanics, Blacks, people with obesity, and women, a new report shows.

“The percentage of adults with food insecurity ­– the lack of access to adequate food – more than doubled between 1999 and 2016,”  said Candice Myers, PhD, assistant professor at Pennington Biomedical Research Center and lead author of the article published in JAMA.  “The COVID-19 pandemic has undoubtedly worsened the situation.  The country may face long-term economic and health consequences unless we solve this public health crisis.”

The study looked at national trends in food insecurity among U.S. adults from 1999 to 2016 using data from the National Health and Nutrition Examination Survey. The study found that food insecurity rates jumped to:

35 percent among Hispanic adults, from 19.5 percent
1 percent among Blacks, from 12.4 percent.
6 percent among people with obesity, from 10.4 percent.
2 percent among women, from 8.7 percent.

Dr. Myers said the study further solidifies the link between food insecurity and unhealthy body weight.

Food insecurity has a range of health consequences, all of them negative, she said.  Obesity is key among them. 

“Food insecurity and obesity are not mutually exclusive,” Dr. Myers said.  “Rather, these health issues are linked in such a way that a solution will require public policy that addresses both at the same time.”

Pennington Biomedical Executive Director John Kirwan, PhD, said the intersection of food insecurity and chronic disease highlights the impact of the research center’s work.

“Our research has set the stage to not only continue our current efforts to explore these issues, but also develop new and innovative projects that delve into understanding their impact on the health of the citizens of our community, state and the entire country,” Dr. Kirwan said.

To find out more about how to help, go to:

Greater Baton Rouge Food Bank
Feeding Louisiana
Feeding America

Dr. Myers’ study is at https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2769137.

This work was supported by award GM104940 from the National Institute of General Medical Sciences of the National Institutes of Health, which funds the Louisiana Clinical and Translational Science Center, and by grant P30DK072476 from Nutrition Obesity Research Centers (titled “Nutrition and Metabolic Health Through the Lifespan”) sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases.

The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Instagram users who post self-harm content online are choosing ambiguous hashtags in an attempt to circumvent the social media platform's ban on harmful content, a researcher at the University of Otago, Wellington, has found.

PhD student Jacobo Picardo reviewed research published during the past 10 years about suicide and self-harm content posted on Instagram. Only 10 studies had been published up to the beginning of 2020. Seven of the studies described samples of publicly available Instagram content, while three surveyed or interviewed Instagram users.

Instagram, which has more than a billion active monthly users, is one of the most popular social media platforms among young people.

The studies showed the photo and video-sharing site was a popular platform for posting self-harm content, with depictions of cuts, usually on the arms or legs, the most common.

Users often choose ambiguous hashtags designed to avoid censorship by Instagram, which banned graphic self-harm images from its platform in February 2019, and extended the ban to fictional depictions of self-harm or suicide last October.

Mr Picardo says online communities have emerged around these hashtags, allowing users with self-harm or suicide interests to come together online.

"Instagram's ability to flag such content is limited because hashtags are evolving faster than they can be tracked and assessed by the platform's content moderators.

"Surveillance methods drawing on hashtag and captions to identify self-harming content do not appear to be very effective. Moreover, Instagram's tool for users to report negative content has not been widely adopted, with few Instagram users aware of it.

"Instagram is looking into new technologies, such as using AI automatic image recognition algorithms, which help identify such content. However, there is a lack of consensus about how to best tackle this content."

Mr Picardo says the actual prevalence of self-harm or suicide content on Instagram is unknown, but researchers have found the nature of the content to be diverse, with posts ranging from pictures of wounds and selfies to memes and references to movies or lines from songs.

"In general, self-harm content on Instagram receives a high volume of audience engagement and attention, and visual and gorier posts are likely to receive a greater number of 'likes'."

Users' comments are most likely to show empathic support and care for the content posters, but studies show concerns there may be negative impacts on viewers engaging with such content.

"Self-harm or suicide content online often does not follow media guidelines to prevent negative effects, and some studies show concerns that such content could trigger others to self-harm, as well as perpetuating such behaviour by normalising and validating it and through the sharing of self-harm methods and tips for concealment. However, causal copycat effects have not been proven, and further studies are needed to look into this."

Recent research suggests such content reflects users' expressions of distress, and that there could be some benefits from others engaging with it online, such as by providing a supportive online community and offering alternative coping strategies and tips on reducing self-harming.

Mr Picardo says more accurate and reliable information about those who engage with self-harm content on Instagram is needed.

"We need researchers to speak directly to online users in order to obtain reliable information about them and their views of what constitutes self-harm content online, why they engage with it, how it affects them and how it relates to their lives offline," he says.

As part of his PhD research, he has begun interviewing young adults in Wellington to gain a better understanding of their views of the issue.

New research from UBC Okanagan shows that salvage logging on land damaged by wildfires has negative impacts on a variety of animals.

While post-fire salvage logging is used to mitigate economic losses following wildfire, Karen Hodges, a biology professor in the Irving K. Barber Faculty of Science, says the compounded effects of wildfire and post-fire salvage logging are more severe than what wildlife experience from fire alone.

Wildfires have been increasing in prevalence and severity in recent decades, Hodges says, and salvaging trees after a fire is a common practice. However, the scale and intensity of post-fire logging removes important regenerating habitat for a variety of forest species.

"When trees are removed from a newly burned landscape, birds and mammals lose the last remnants of habitat," she adds. "Salvage logging decreases forest biodiversity and changes ecological processes of post-fire forest regeneration. Mosaics of regenerating forest are changed through the removal of standing and downed trees, which would naturally remain on the landscape following fire."

Hodges notes while BC's logging industry is heavily regulated, harvesting differs between normal harvests and post-fire logging. More frequent wildfires mean an increase in post-fire salvage logging.

"Salvage logging is often done urgently as harvesters attempt to get burned timber to market before the wood deteriorates," she says. "Salvage logging is also done at larger scales and intensities than a standard harvest. This post-fire harvest means wildlife species that can manage after a wildfire do not rebound as quickly from this second disturbance."

The research led by master's student Angelina Kelly studied populations of snowshoe hares and red squirrels in post-fire and salvage-logged areas of the Chilcotin--an area severely impacted by wildfires in 2010 and 2017. Hares and squirrels are important species because predators such as coyote, bobcats, marten, lynx, goshawks and great horned owls rely on them to survive.

"The main concern of a snowshoe hare is to avoid predators. Hares select stands with protective vegetation cover and avoid open areas like clearcuts--even if those areas provide food," says Kelly. "Because of their need for vegetative cover, snowshoe hare populations decrease immediately following fires, clearcut logging or salvage logging."

Their study area, about 32,000 hectares on the eastern edge of the Chilcotin Plateau, was ravaged by wildfire in 2017. While looking for evidence of hares and squirrels, the researchers also conducted vegetation surveys to quantify important habitat attributes in mature forests, burned forest and areas where salvage logging had taken place.

"Post-fire salvage logging greatly changed the habitat structure of post-fire stands, removing vegetative cover and rendering those sites unsuitable for hares and red squirrels," says Kelly. "The post-fire salvage-logged areas supported no hares or red squirrels for at least eight to nine years after the initial wildfire. Burn areas where no post-fire harvesting took place supported low densities of hares and red squirrels by that time."

This loss of prey species contributes to declines in forest predators such as lynx, marten and owls, as Hodges and her team have documented in this region and other studies.

Hodges and Kelly stress that any trees or vegetation left after a wildfire are critical for wildlife immediately after a fire, and promote a healthy mosaic of post-fire habitat. Residual trees facilitate regeneration of burned areas, while also supporting wildlife.

MADISON, Wis. -- As Americans begin pulling up their sleeves for an annual flu vaccine, researchers at the University of Wisconsin-Madison have provided new insights into an alternative vaccine approach that provides broader protection against seasonal influenza.

In a study published in Cell Reports Medicine today (Sept. 22), scientists describe a T-cell-based vaccine strategy that is effective against multiple strains of influenza virus. The experimental vaccine, administered through the nose, delivered long-lasting, multi-pronged protection in the lungs of mice by rallying T-cells, specialist white blood cells that quickly eliminate viral invaders through an immune response.

The research suggests a potential strategy for developing a universal flu vaccine, "so you don't have to make a new vaccine every year," explains Marulasiddappa Suresh, a professor of immunology in the School of Veterinary Medicine who led the research. The findings also aid understanding of how to induce and maintain T-cell immunity in the respiratory tract, a knowledge gap that has constrained the development of immunization strategies. The researchers believe the same approach could apply to several other respiratory pathogens, including the novel coronavirus that causes COVID-19.

"We don't currently have any vaccine for humans on the market that can be given into the mucosa and stimulate T-cell immunity like this," says Suresh, a veterinarian with specialty training in studying T-cell responses to viral infections.

The strategy addresses the Achilles' heel of flu vaccines, which is to achieve specific antibody responses to different circulating influenza strains annually, by harnessing T-cell immunity against multiple strains. In particular, the new approach calls into action tissue-resident memory T-cells, or TRM cells, which reside in the airways and lining of lung epithelial cells and combat invading pathogens. Like elite soldiers, TRM cells serve as front line defense against infection.

"We didn't previously know how to elicit these tissue-resident memory cells with a safe protein vaccine, but we now have a strategy to stimulate them in the lungs that will protect against influenza," explains Suresh. "As soon as a cell gets infected, these memory cells will kill the infected cells and the infection will be stopped in its tracks before it goes further."

Flu vaccines work by arming the immune system with an enhanced ability to recognize and fight off the flu virus. Vaccines introduce proteins found on the surface of flu viruses, prompting the immune system to produce antibodies that are primed to react should the virus attack.

However, because strains must be predicted ahead of flu season in order to produce vaccines, the vaccine in any given year may not completely match the viral strains in circulation that season. Flu viruses frequently mutate and can differ across time and from region to region. In addition, protection is neither long-lasting nor universal.

"Even though current vaccines that people get annually stimulate antibody responses, these antibodies don't cross-protect," notes Suresh. "If there is a new flu strain not found in that year's vaccine, the antibodies that we generated last year won't be able to protect. That's when pandemics happen because there is a completely new strain for which we have no antibodies. That is a really big problem in the field."

The vaccine developed by Suresh and his team is directed against an internal protein of influenza -- specifically, nucleoprotein. This protein is conserved between flu strains, meaning its genetic sequences are similar across different strains of flu.

The vaccine also utilizes a special combination of ingredients, or adjuvants, that enhance an immune response, which the researchers developed to stimulate protective T-cells in the lungs. These adjuvants spur T-cells to form into different subtypes -- in the case of the experimental flu vaccine, memory helper T-cells and killer T-cells. By doing so, the vaccine leverages multiple modes of immunity.

Killer T-cells hunt down and kill influenza virus-infected cells. Helper T-cells assist killer T-cells and produce molecules to promote influenza control. In laboratory studies, the team found that both T-cell types were needed to protect against flu.

Researchers demonstrated in a mouse model of influenza that the vaccine provides long-lasting immunity -- at least 400 days after vaccination -- against multiple flu strains. They will next test the vaccine in ferrets and nonhuman primates, two animal models of influenza research more biologically similar to human infection and transmission.

The vaccine's combination of adjuvants makes it adaptable to other pathogens and "expands the toolbox" for vaccine research, notes Suresh. He and his team have devised ways to program immunity to target multiple respiratory viruses. They are currently testing the same vaccine strategy against tuberculosis, which infects more than 10 million people globally each year, and human respiratory syncytial virus, or RSV, a major cause of lower respiratory tract infections during infancy and childhood.

The researchers believe the same vaccine technology can applied against SARS-CoV-2, the coronavirus that causes COVID-19. "Based on the COVID-19 immunology, we know this vaccine strategy would most likely work," says Suresh.

The team is now developing an experimental vaccine against COVID-19 and conducting laboratory tests to measure its effectiveness in mice and hamsters, animal models for COVID-19. Initial unpublished studies in mice show that the vaccine stimulates strong T-cell immunity against COVID-19 in the lungs.

Along with its adaptability, this vaccine approach may harbor important safety benefits. Typically, long-lasting T-cell immune responses are stimulated by live vaccines. For instance, the measles, mumps and chickenpox vaccines administered worldwide are live, replicating vaccines -- essentially benign versions of the pathogenic organism. These live vaccines stimulate strong, almost lifelong immunity. However, they can't typically be given to pregnant or immunocompromised individuals due to health risks.

In the case of the UW-Madison team's vaccine, because it is a protein vaccine and not a live vaccine, it should be safe for delivery to those who are pregnant or immunocompromised -- an advantage in delivering protection to a wider patient population. Suresh says that in recent years, vaccine development efforts have shifted away from live vaccines toward protein vaccines because an increasing number of people are living with compromised immune systems due to chemotherapy, radiation treatments or conditions such as HIV/AIDS.

"Previously, we didn't know how to induce T-cell immunity in the lung without live viruses," says Suresh. "If we cleverly use a combination adjuvant, which we have developed, you can induce T-cell immunity that should stay in the lungs and protect longer."

A group of social scientists who conduct cross-cultural research are casting a critical lens on their own practices.

While this is by no means the first time that such self-reflection has been undertaken, the analysis, published in the Sept. 23 issue of Proceedings of the Royal Society B, is particularly timely given the growing appetite for including diverse populations in work on demography, health, economic development, cooperation, cognition, infant and child development, and belief systems. The push to expand research beyond western, educated, industrialized, rich, and democratic societies has meant that scientists are striving to capture evermore cultural diversity -- but how does this actually work when embarking on a research endeavor and selecting a community to study?

The international group of authors, led by Tanya Broesch (Simon Fraser University, British Columbia), Alyssa Crittenden (University of Nevada, Las Vegas, USA), and Monique Borgerhoff Mulder (UC Davis, USA; Max Planck Institute for Evolutionary Anthropology, Germany), draw upon years of cross-cultural work in anthropology and psychology to provide actionable suggestions to address the logistical and ethical quandaries of study site selection, engagement with communities in research, and the significance of culturally-appropriate research methods and reporting practices - both in publications and in media representations.

The authors argue that if researchers, like themselves, fail to seriously consider "the historical, political, sociological and cultural forces" acting on both the communities where they work, and the individuals within those societies, inaccurate and possibly harmful inferences might be drawn. This is particularly the case where investigators have limited time and budget, something that might be glossed as "helicopter anthropology", Borgerhoff Mulder commented.

They suggest that it is the general approach of the researchers -- from project development through to publication and data management -- that matters, where establishing and maintaining communication with participants is always prioritized.

"There is no one-size-fits-all approach, yet a productive baseline may be for researchers to consider community inclusion as part of their project design from the start," the authors write. "Ideally, the community is not only central to the planned research, but is leading it."

The research team, which spans all stages of academic careers from doctoral students to senior scholars, argues that despite the long history of exploitation and colonialism inherent in much ethnographic discourse, comparative research in the 21st century can be successfully and ethically conducted in a wide range of communities (including small-scale societies) across a variety of academic disciplines - as long as a community-centered approach is taken.

Access the full article here: http://dx.doi.org/10.1098/rspb.2020.1245.

Reno, Nev. (Sept. 22, 2020) - For people who suffer from asthma, wildfire smoke is more hazardous than other types of air pollution, according to a new study from the Desert Research Institute (DRI), the Renown Institute for Health Innovation (Renown IHI) and the Washoe County Health District (WCHD).

The study, which published last month in the journal Environmental Health, examined associations between airborne particulate matter (PM) from sources such as wildfire, transportation and industry, and medical visits for asthma at Renown Health's emergency departments and urgent care centers in Reno, Nev. during the six-year period from 2013-2018.

According to their results, on days when wildfire smoke was present, elevated levels of PM2.5 (fine particles of 0-2.5 micrometers in size, about 30 times smaller than a human hair) led to a 6.1 percent increase in medical visits for asthma patients when compared with days of similar pollution levels that came from non-wildfire sources.

"Since we found significantly stronger associations of PM2.5 with asthma visits when wildfire smoke was present, our results suggest that wildfire PM is more hazardous than non-wildfire PM for patients with asthma," said lead author Daniel Kiser, M.S., Data Scientist with DRI and Renown IHI.

An increase in the harmfulness of PM from wildfires compared to PM from other sources may be attributable to differences in the chemical composition of PM or changes in human behavior, since people are more likely to be outdoors in the summer, when wildfires typically occur. The research team notes that caution should be used when applying these results to other areas of the country, such as the Southeastern United States, since the harmfulness of wildfire smoke may be affected by the type of fuel that is being burned. Other factors, such as the distance that wildfire smoke was carried by the wind and burn temperature, may also play a role in the harmfulness of wildfire smoke.

The researchers found that air quality in the Reno area was affected by wildfire smoke on a total of 188?days during the study period. A total of 18,836 asthma-related emergency room and urgent care visits occurred over the same five-year period of time, indicating that the influences of wildfire smoke and other types of air pollution on this medical condition are important to understand.

"In places like Reno, where wildfire events occur regularly during parts of the year and are expected to become more frequent in the future, an accurate understanding of the impacts of wildfire smoke on population health is critical," Kiser said.

The small blood vessels in muscles of women after menopause are less able to grow compared to young women, according to new research published today in the Journal of Physiology. This means exercising before menopause is all the more important for women in order to develop blood vessels in muscles, and thus the ability to develop muscle strength.

Recent studies have shown that there are some substantial differences in the way the blood vessels, which influences susceptibility to conditions like heart disease and stroke, are affected by aging and physical activity between women and men, a difference which to a large extent is related to the female sex-hormone, estrogen.

Estrogen is protective of the heart and blood vessels in women for about half of their lives, but, at menopause, there is an abrupt permanent loss of estrogen, leading to a decline in the health of our blood vessels.

In this study, the researchers at the University of Copenhagen examined the smallest of blood vessels in muscle, called capillaries. The number of capillaries in skeletal muscle can change a lot and is mainly affected by how much the muscle is used, such as during exercise. This is the first study to isolate and examine cells from skeletal muscle samples of young and old women.

Capillaries in skeletal muscle (as opposed to heart muscle) are very important for skeletal muscle function, physical capacity and health as it is here that oxygen and nutrients, such as sugar and fats, are taken up into muscle when needed. It is known that loss of capillaries in muscle can affect insulin sensitivity and thereby the development of Type II diabetes.

The study also found that, when the aged women completed a period of aerobic exercise training by cycling, they did not achieve an increase in the number of capillaries in muscle, in contrast to what has been repeatedly shown in young and older men.

Aging is known to lead to a loss of capillaries in the muscle, an effect which, in men, has been shown to be counteracted by a physically active lifestyle. This new study suggests that women do not attain capillary growth as readily and that an underlying cause may be a flaw in the cells that make up capillaries.

It is important to underline that both men and women have a vast benefit from being physically active throughout life, regardless of age, but the current study supports the idea that women may benefit from being physically active before menopause, while they still have estrogen, so that they have a good physical starting point as they get older.

The researchers studied older women (over 60 years old) and young (around 25 years old) ones. The women underwent a series of physical tests, and the researchers obtained small samples from their thigh muscles.

The muscle biopsies were used to isolate blood vessel cells and muscle cells for further detailed study in the lab. The older women then also conducted 8 weeks of cycling training, where they trained three times per week at moderate to high intensity.

The women were tested for fitness and several other parameters before and after the training. After the training period samples were again obtained from the thigh muscle and used for analysis of capillary number and specific proteins.

Line Nørregaard Olsen, first author on the study said:

"Another aspect that is worth highlighting is that many people doubted that the older women could handle such intensive training. However, the women, who conducted the cycle exercise training (spinning training) 3 times per week for 8 weeks, with heart rates over 80% of maximal heart rate for more than 60% of the time, were excited and handled the training without problems. This underlines that the popular view of how hard women of that age can train should be revised."

A systematic review of evidence being presented at this week's ESCMID Conference on Coronavirus Disease shows that air around patients with COVID-19, as well as patients toilets, and staff and public areas in hospitals are all show significant levels of contamination with SARS-CoV-2. The study is by Dr Gabriel Birgand, University Hosptial Centre Nantes, France, and colleagues.

Controversy remains worldwide regarding the transmission mode of SARS-CoV-2 virus in hospital settings. In this study, the authors reviewed the current evidence on the air contamination with SARS-CoV-2 in hospital settings, the viral load and the particle size, and the factors associated to the contamination.

The authors searched the MEDLINE, Embase, Web of Science databases for original English-language articles detailing COVID-19 air contamination in hospital settings between 1 December 2019 and 21 July 2020.

The positivity rate of SARS-CoV-2 viral RNA and culture were described and compared according to the setting, clinical context, air ventilation system, and distance from patient. The SARS-CoV-2 RNA concentrations in copies per m3 of air were pooled and their distribution were described by hospital areas.

Among 2,034 records identified, 17 articles were deemed eligible and included in the review. Overall, 27.5% (68/247) of air sampled from close patients' environment were positive for SARS-CoV-2 RNA, with no difference between settings (ICU: 27/97, 27.8%; non-ICU: 41/150, 27.3%). Just 1/67 (1.5%) of samples in the air less than 1 metre from the patient tested positive for SARS-CoV-2, and just 4/67 (6%) of samples 1-5 metres away. (see results in abstract and poster)

In other areas, the positivity rate was 23.8% (5/21) in patient toilets, 9.5% (20/221) in clinical areas, 12.4% (15/121) in staff areas, and 34.1% (14/41) in public areas (see table in abstract). A total of 78 viral cultures were performed, and 3 (4%) were positives (meaning the virus was viable and capable of reproduction), all from close patients' environment (3/39, 7.7%) in non-ICU settings.

The median SARS-CoV-2 RNA concentrations were found to be 10 times higher in patient toilets than in the patients' rooms.

The authors conclude: "In hospital, the air near COVID-19 patients is frequently contaminated with SARS-CoV-2 RNA, with however, poor proof of its infectivity - meaning we detected the viral RNA, but when trying to culture (grow) these samples, there was little evidence of viable virus. High viral loads found in toilet/bathrooms, staff and public hallways means these areas require strong compliance with cleaning measures and personal protective equipment."

CORVALLIS, Ore. - Squeezed by changing ocean conditions that limit their food options and the long-term loss of old forest needed for nesting, marbled murrelets would benefit most from conservation efforts that take both ocean and forest into account, new research by Oregon State University shows.

Published in Conservation Letters, the findings are based on two decades of murrelet surveys at nearly 20,000 sites in the Oregon Coast Range and illustrate how the elusive seabird is at risk of its habitat gradually shrinking to the point of local extinctions or worse.

"It turns out that the same ocean conditions that influence salmon returns, including the forage fish murrelets need to successfully nest, had a huge influence on the likelihood that murrelets will come inland to breed," said lead author Matt Betts, a researcher in the Oregon State College of Forestry and the director of the OSU-based Forest Biodiversity Research Network. "Given that these prey items tend to be in lower abundance when ocean temperatures are high, changing climate conditions could reduce prey availability as well as the tendency for murrelets to nest in the future."

Marbled murrelets are closely related to puffins and murres, but unlike those birds, murrelets raise their young as much as 60 miles inland in mature forests. Disturbance in either the ocean or forest environment has the potential to impact murrelet populations.

"There aren't many species like it," said study co-author and project director Jim Rivers, also a faculty member in the College of Forestry. "There's no other bird that feeds in the ocean and commutes such long distances inland to nest sites. That's really unusual."

The dove-sized bird spends most of its time in coastal waters eating krill, other invertebrates and forage fish such as herring, anchovies, smelt and capelin. Murrelets can only produce one offspring per year, if the nest is successful, and their young require forage fish for proper growth and development.

Murrelets generally nest in solitude, although multiple nests sometimes occur within a small area. They typically lay their single egg high in a tree on a horizontal limb at least 4 inches in diameter, with Steller's jays, crows and ravens the main predators of murrelet nests.

"The end goal for these birds is to be very secretive and quiet so predators don't find their nests and they can produce young,' said Rivers.

Along the West Coast, marbled murrelets are found regularly from Santa Cruz, California, north to the Aleutian Islands. Their populations have been declining by about 4% a year in Washington, Oregon and California, and the species is listed as threatened under the U.S. Endangered Species Act in those states.

"Early on in our work, we noticed strong fluctuations in the numbers of marbled murrelets coming inland to nest, so this study was about trying to get to the bottom of those highs and lows," Betts said. "We found the first evidence that ocean conditions combined with old-forest nesting habitat influence the murrelets' long-term occupancy dynamics. In particular, we learned ocean conditions are a key driver of those dynamics."

The finding has potential key implications for forest policy in Oregon, where any state-owned site that goes two consecutive years without murrelet detection is classified as unoccupied and thus available for timber harvest.

"Our data show that below-average ocean conditions might last for more than two successive years," Rivers said. "That means there could be a scenario where sites on state lands that are suitable for breeding go unused for more than two years which, under current guidelines, would let them be considered available for harvest. Thus, murrelets might be missing from inland sites not because the forest is unsuitable for nesting, but because they have inadequate forage fish during the summer breeding season. That means it is critical that we consider factors that influence both marine food resources and terrestrial nesting habitat when considering how to recover murrelet populations."

Betts was part of a research collaboration that published a 2019 paper in the Proceedings of the National Academy of Sciences that showed that old forest is still declining across the Pacific Northwest 25 years into the Northwest Forest Plan, a 100-year federal road map to protect older forests.

"This is now less due to the saw and more due to fire," he said. "That means that even with strong land conservation measures, climate could not only result in warmer ocean conditions but also greater fire frequency and extent, and therefore more old forest loss."

From toilet paper to industrial chemicals, there's no doubt the COVID-19 pandemic has been disruptive to global supply chains.

But how important are large, multinational companies in maintaining both local and international logistic networks and should governments be so focused on maintaining larger organisations through subsidies and bail-outs over their smaller counterparts?

A new network analysis by researchers from the University of Sydney's School of Project Management and the Centre for Complex Systems within the School of Civil Engineering has found that large, multi-national organisations are not always as crucial to local supply chains, and that it's sometimes the smaller operators that can deliver the hardest logistic shocks to a community when disrupted.

"In the current context where a pandemic is spreading in the world, industry output has already been severely impacted and supply chains have been disrupted. The full effect of this will only become apparent in coming months and years, but it's clear that COVID-19 has already caused 'kinks' in the movement of goods and services around the globe," said lead author Dr Mahendra Piraveenan from the Faculty of Engineering.

"Our study has sought to understand whether types of businesses play more central or local roles, and how shocks might cascade along the chain of firms.

"Governments often provide bail-out packages to large organisations in a bid to save jobs. However, organisations which are central to supply chains should also be supported, even if they are relatively small, because they may be more important to a country's economy.

"For example, there is no point bailing out a car manufacturer if many of the companies that supply the necessary parts go bankrupt - that will mean the car manufacturer cannot get back on its feet regardless."

School of Project Management academic, Dr Petr Matous said that when the operations of some organisations are disrupted by social distancing policies, they may send shocks "downstream" to their clients who cannot access their components, which in turn triggers disruptions to the clients of clients.

"However, how much a failure of one firm affects economies around the world depends on multiple factors, it's not so simple that a disruption of a larger firm would always cause more losses. The structure of the international supply networks plays a role in this," said Dr Matous.

Organisations deliver supply chain shocks like COVID-19 super-spreaders

"Similarly to COVID-19 "super-spreaders", organisations that can facilitate the spread of supply chain shocks are not always the biggest ones nor necessarily the ones with the most supply chain connections," said Dr Matous.

"We identified when supply chain clusters overlap with country boundaries but often they don't and in such cases and industries, fast international contagion of shocks is possible," he said.

The researchers also found that organisations that originate from a certain country, but register themselves elsewhere, are often less central to the supply chain network of the country in which they are registered, yet are more central in the global supply chain network due to their international roots.

For example, a Chinese packaging group that was registered in the United States was found not to be important to their supply chains but was important on a global scale.

Strength in numbers

The study found that structural clustering - known as community structures - of global supply chains are strongly influenced by the industries that organisations belong to.

"We identified industry sectors and countries which tend to form strong communities in terms of supply chains, and are therefore are less vulnerable to fluctuations in the global supply chain network, such as finance, insurance, real estate, transportation, construction, manufacturing," said Dr Piraveenan.

Insight-HXMT, China's first space X-ray astronomical satellite, has discovered a low-frequency quasi-periodic oscillation (QPO) above 200 kiloelectron volts (keV) in a black hole binary, making it the highest energy low-frequency QPO ever found. The scientists also found that the QPO originated from the precession of a relativistic jet (high-speed outward-moving plasma stream) near the event horizon of the black hole. These discoveries have important implications for resolving the long-running debate about the physical origin of low-frequency QPOs.

This work, published online in Nature Astronomy on Sept. 21, was primarily conducted by scientists from the Institute of High Energy Physics (IHEP) of the Chinese Academy of Sciences (CAS), the University of Southampton (United Kingdom), Eberhard Karls University of Tübingen (Germany), and the Shanghai Astronomical Observatory of CAS.

Low-frequency QPOs, discovered in the 1980s, are a common observational timing feature in transient black hole binaries. They are quasi-periodic, but not precisely periodic, modulations in light curves. For more than 30 years, the origin of low-frequency QPOs was not understood. The two most popular models explaining their origin are: 1) the oscillations are caused by the instability of the accretion disk when matter rotates around and finally falls into the black hole; and 2) the quasi-periodic X-ray modulations are produced by the oscillation or precession of the coronal X-ray emitting region close to the black hole.

Before the era of Insight-HXMT, X-ray satellites could only detect and study low-frequency QPOs below 30 keV; thus, it was difficult to test these models. Insight-HXMT, in contrast, has a wide effective energy range of 1-250 keV and has the largest effective area above 30 keV. Therefore, after Insight-HXMT was launched, scientists expected it would detect rich low-frequency QPOs above 30 keV, and thus be able to fully test previous models.

The new black hole X-ray binary MAXI J1820+070, consisting of a black hole of several solar masses and a companion star, started to undergo an outburst on March 11, 2018. It has been one of the brightest X-ray sources in the sky for a long time. Insight-HXMT quickly responded and performed high-cadence pointing observations on this source for several months, accumulating a huge amount of observational data.

Based on these data, the scientists found that the low-frequency QPO of MAXI J1820+070 appeared in a wide energy range and its maximum detection energy exceeded 200 keV, which is almost an order of magnitude higher than previous QPOs observed by other telescopes, indicating that the QPO could not come from the thermal radiation region of the accretion disk. Further studies revealed that the frequency and variability amplitude of the QPO are energy independent and the high-energy QPO precedes the low-energy one.

These results unambiguously conflicted with most currently existing models. Therefore, the scientists proposed that the low-frequency QPO was produced by the precession of a jet near the black hole's event horizon; the precession was probably caused by the frame-dragging effect of general relativity, generated by the rotation of the black hole.

Jets are high-speed matter streams moving at close to the speed of light. Plenty of jets have been observed in black hole binaries and distant quasars hosting supermassive black holes (i.e., those of millions to tens of billions of solar masses) in the radio, optical and X-ray bands. Jets are an important observational characteristic of black hole systems, and are the main means by which black holes influence the surrounding environment via feedback when swallowing nearby matter.

However, these jets are far from black holes. They are usually located at a distance of more than a million times the black hole's event horizon. At such a long distance, the black hole's gravitational force actually has no effect. Therefore, it is unclear where these jets are generated, how far they are from the black holes, how they can escape from the strong gravitational field of the black holes and how they are accelerated to a speed close to the speed of light.

Insight-HXMT's discovery is particularly important because it's the first time a jet has been found only hundreds of kilometers away from a black hole (i.e., several times the black hole's event horizon). As the closest relativistic jet observed in a black hole so far, the finding is of great significance for studying the relativistic effects, dynamical processes and radiation mechanisms.

The Institute of High Energy Physics proposed the Insight-HXMT satellite project and leads the development of its payloads, ground application system and scientific research. The China Academy of Space Technology, Tsinghua University, the National Space Science Center of CAS and Beijing Normal University have also participated in the project and have made important contributions.

New bioarchaeology research from a University of Otago PhD candidate has shown how infectious diseases may have spread 4000 years ago, while highlighting the dangers of letting such diseases run rife.

Yaws - from the same bacteria species responsible for syphilis (Treponema pallidum) - is a childhood disease causing highly infectious skin lesions. It is spread via touch from person to person and, in advanced cases, can leave sufferers with severe bone disfigurement. While it is easily curable in its early stages, the bone disfigurements are irreversible.

The disease has been eradicated from much of the world but is still prevalent in the Western Pacific, affecting some 30,000 people. A previous global attempt to eradicate this tropical disease failed at the last hurdle in the 1950's and a new attempt was curtailed by the COVID-19 outbreak, University of Otago Department of Anatomy PhD candidate Melandri Vlok says.

Ms Vlok's PhD research uses archaeology to shed light on the spread of diseases when different human populations interact for the first time. Her specific interest is in what she calls the "friction zone", where ancient agricultural people met hunter gatherer people.

In 2018 she travelled to Vietnam to study skeletal remains from the Man Bac archaeological site. From the Ninh Bình Province in the north of the country, Man Bac was excavated in 2005 and 2007 and has delivered a treasure trove of information for archaeologists thanks to its role during the transition away from foraging to farming in Mainland Southeast Asia.

Now housed in Hanoi's Institute of Archaeology those remains are well-studied but had not been analysed for evidence of yaws, Ms Vlok says.

Her supervisor at Otago, renowned bioarchaeologist Professor Hallie Buckley, had seen what she thought might be yaws on a photograph of Man Bac remains. Professor Buckley travelled with Ms Vlok and together with a passionate team of experts from Vietnam they confirmed their suspicions, Ms Vlok says. Later, Ms Vlok found a second example of the disease.

This was significant, as the Man Bac site dates back 4000 years. Till now, there was no strong evidence for yaws in prehistoric Asia.

Ms Vlok's research suggests yaws was introduced to hunter-gathers in present-day Vietnam by an agricultural population moving south from modern-day China. These hunter-gathers descended from the first people out of Africa and into Asia who also eventually inhabited New Guinea, the Solomon Islands and Australia.

The farmers had been in China for at least 9000 years but it wasn't until around 4000 years ago farming was introduced to Southeast Asia. It is possible this movement of people brought diseases, including yaws, at the same time.

Ms Vlok says the length of time the disease has existed in the region is relevant when addressing how hard it has been to eradicate.

"This matters, because knowing more about this disease and its evolution, it changes how we understand the relationship people have with it. It helps us understand why it's so difficult to eradicate. If it's been with us thousands of years it has probably developed to fit very well with humans."

This year's COVID-19 pandemic has focused people's attention on infectious diseases, and there are lessons to be learned from the past, Ms Vlok says.

"Archaeology like this is the only way to document how long a disease has been with us and been adapting to us. We understand with COVID-19 today how fantastic that disease is at adapting to humans. And Treponema has been with us for so much longer.

"So, this shows us what happens when we don't take action with these diseases. It's a lesson of what infectious diseases can do to a population if you let them spread widely. It highlights the need to intervene, because sometimes these diseases are so good at adapting to us, at spreading between us."

Classifying olive oils into the categories of extra virgin (EVOO), virgin (VOO) and lampante (LOO) is still quite a challenge to deal with since the official method includes physical-chemical and sensory analyses by means of a panel of tasters. These tasters need to be specialized, and on many occasions are not available, in addition to being expensive and slow. All of this has created the necessity to develop new analytical methods using affordable, reliable tools that are transferable to the industry.

The AGR-287 research group, led by Professor Lourdes Arce, was a pioneer in demonstrating the possibilities that Gas Chromatography along with Ion Mobility Spectrometry (GC-IMS) could provide in order to classify oils into three categories (EVOO, VOO and LOO). This methodology allows for analyzing two samples an hour. When a representative number of samples has been analyzed, the chemical information gathered is dealt with using statistical tools in order to create calibration equations that will allow for classification of samples of unknown oil into their respective categories in the future.

A crucial point in the validation of this method is the number of samples needed to calibrate the equipment. The research done has shown that, in order to obtain good results, it is not only necessary to analyze a representative number of samples but to also have samples of olive oil belonging to each of the three categories, from different varietals, from different seasons and tasted by at least two panels whose results coincide. Hence, these methods do not seek to substitute, but rather complement and support, the role of accredited tasting panels. In these research projects, the importance of building a bank of oil samples has been demonstrated, so that they can be reference standards that will be used to construct calibrated equations. These equations will establish the categories of analyzed oil samples.

The results obtained from this research have aroused interest among different businesses in the oil sector that are currently collaborating on carrying out transferring this research to the industry. What is more, using the knowledge ensuing from this research, a new instrument is being developed that will classify oils based on the use of IMS technology. This makes up one of the lines of Project Innolivar, whose aim is to increase competitiveness, international positioning, technological capacity and financial profitability of olive groves and their associated business sector.

Another research project being carried out by doctoral student Natividad Jurado, has revealed that the proper classification of oils requires taking the chemical compounds that each taster discerns into consideration as well. The proposed methodology is based on the extraction of certain compounds present in oil, for instance polyphenols, and then determining them using capillary electrophoresis (CE-UV) - a technique to separate different molecules - coupled with an ultraviolet detector. In a paper published in Talanta, the integrated use of both techniques (CE-UV and GC-IMS) was suggested in order to detect non-volatile compounds detected by the mouth, and also the volatile compounds detected by the nose. All the information obtained with both techniques is dealt with by statistical tools suitable for classifying an oil sample into the correct category. This fusion of data has been proven to be useful when classifying borderline samples that are at the interface of two groups (EVOO/VOO or VOO/LOO).