Culture

A new study of human olfactory cells has revealed that viral invasion of supportive cells in the nasal cavity might be driving the loss of smell seen in some patients with COVID-19. The findings show that non-neuronal cells in the brain and nose express genes critical for SARS-CoV-2 entry, while neurons do not; therefore, non-neuronal cells are likely to be the primary targets for virus-induced damage leading to loss of smell, or anosmia. Recent investigations into COVID-19-associated anosmia showed that cells from the human upper airway express high levels of receptor genes involved in SARS-CoV-2 entry, suggesting that these respiratory epithelial cells serve as viral reservoirs during CoV-2 infection. However, these studies did not investigate the sheet of cells that line the nasal cavity, called the olfactory epithelium - the first entryway for pathogens before they reach the respiratory epithelium. Using bulk RNA sequencing of human cells from the nasal mucosa, David Brann and colleagues identified cell types in the olfactory epithelium in the nose and the brain's olfactory bulb that express two key receptor genes involved in SARS-CoV-2 entry, ACE2 and TMPRSS2. Single cell RNA sequencing of these cells and neurons provided the key insight that neither gene was detected in olfactory neurons, but both were highly expressed by support cells, stem cells, and perivascular cells in the nose and brain. Fluorescent staining of ACE2 in olfactory cells in mice confirmed this result and revealed pervasive expression of ACE2 protein in structural support cells of the nose and in cells that wrap around the capillaries of the olfactory bulb. Identifying the mechanisms that underlie the olfactory symptoms of COVID-19 can help lead to new diagnostics for SARS-CoV-2 infection, yield insights into the cellular dynamics of the nose, and propel future treatments for anosmia, the authors say.

A new study found raised levels of transforming growth factor beta-induced protein (TGFBIp) in blood sampled from roughly 100 people hospitalized for COVID-19, and further found that elevated levels of both the normal and acetylated forms of TGFBIp correlated with the severity of disease symptoms in these patients. While more work will be required to determine whether heightened levels of acetylated TGFBIp can serve as an exclusive, specific, and reliable diagnostic indicator for the severity of COVID-19, the research also suggests that TGFBIp could be a viable therapeutic target to treat severe inflammation - including deadly "cytokine storms" - in patients suffering from severe cases of the disease. While much work has been done to characterize the immune responses of patients with COVID-19, the inflammatory markers and cytokines known to be induced by SARS-CoV-2 infection are often short-lived. Hee Ho Park and colleagues set out to investigate whether increased levels of both the normal and acetylated forms of TGFBIp, a more stable molecule known to activate the immune-regulating transcription factor NF-κB, might serve as a more lasting signal of SARS-CoV-2 infection. The researchers analyzed blood samples from healthy controls and two cohorts of COVID-19 patients: those admitted to a hospital for treatment with relatively mild symptoms, and those who required ICU care to treat acute respiratory distress syndrome (ARDS) and/or sepsis. Compared with the healthy controls, both patient cohorts exhibited elevated levels of TGFBIp, as well as higher levels of acetylated TGFBIp, with the ICU patients exhibiting even greater levels of both protein forms. Upon treating immune cells taken from these patients with antibodies that neutralize TGFBIp, the researchers also observed a decrease in the production of inflammatory cytokines. While further work will be required to validate these results and assess the safety of the neutralizing antibodies, the finding nonetheless suggests that TGFBIp could be targeted to help treat severe inflammation in COVID-19 patients.

Current observations suggest that the coronavirus SARS-CoV-2 causes severe symptoms mainly in elderly patients with chronic disease. However when two pairs of previously healthy young brothers from two families required mechanical ventilation at the intensive care unit in rapid succession, doctors and researchers at Radboud University Medical Center were inclined to consider that genetic factors had a key role in compromising their immune system. Their research identified the gene TLR7 as an essential player in the immune response against SARS-CoV-2. A finding with potentially major consequences for understanding and possibly treatment of COVID-19.

During the wave of COVID-19 patients that flooded Dutch hospitals in the first half of 2020, two young brothers became seriously ill with the SARS-CoV-2 virus and had to be mechanically ventilated in the ICU. One of them died from the consequences of the infection, the other recovered. The severe course of disease in otherwise healthy young brothers was a relatively rare occurrence, especially because the virus mainly affects the elderly. This observation triggered the curiosity of an attentive physician from the MUMC+ department of clinical genetics. She contacted her colleagues in Nijmegen who then investigated why these two young brothers were so severely affected.

Genetic factors

"In such a case, you immediately wonder whether genetic factors could play a role," says geneticist Alexander Hoischen. "Getting sick from an infection is always an interplay between - in this case - the virus and the human immune system. It may be a mere coincidence that two brothers from the same family become so severely ill. But it is also possible that an inborn error of the immune system has played an important role. We investigated this possibility, together with our multidisciplinary team at Radboudumc."

One X-chromosome

All genes (collectively called the exome) of both brothers were sequenced, after which the investigators combed through the data searching for a possible shared cause. Cas van der Made, PhD student and resident at the department of Internal Medicine: "We mainly looked at genes that play a role in the immune system. We know that several of these genes are located on the X-chromosome, and with two brother pairs affected X-chromosomal genes were most suspicious. Women carry two X-chromosomes, while men possess a Y-chromosome apart from the X. Therefore, men have only one copy of the X-chromosomal genes. In case men have a defect in such a gene, there is no second gene that can take over that role, as in women."

Gene identification

That search quickly revealed mutations in the gene encoding for the Toll-like receptor 7, TLR7 for short. There are multiple TLR-genes, which belong to a family of receptors with an important role in the recognition of pathogens (such as bacteria and viruses) and the activation of the immune system. Hoischen: "A few letters were missing in the genetic code of the TLR7 gene. As a result, the code cannot be read properly and hardly any TLR7 protein is produced. TLR7 function has so far never been associated with an inborn error of immunity. But unexpectedly we now have an indication that TLR7 is essential for protection from this coronavirus. So it seems that the virus can replicate undisturbed because the immune system does not get a message that the virus has invaded. Because TLR7, which must identify the intruder and subsequently activate the defense, is hardly present. That could be the reason for the severity of the disease in these brothers."

Additional confirmation

Then, quite unexpectedly, the doctors and researchers at Radboudumc come across another pair of brothers who have fallen seriously ill with COVID-19. Again, they are both under 35 years of age. Both of them were also in the ICU for mechanical ventilation. "Then the question of the role of genetics became even more obvious." says Hoischen. "We also investigated the genetic code of these two brothers, again via the 'rapid-clinical exome' method. This time we saw no deletion, no loss of letters, but a single spelling mistake of one DNA-letter of the TRL7 gene. The effect on the gene is the same, however, because these brothers also do not make sufficient functional TLR7 protein. Suddenly we had four young people with a defect in the same gene, all of whom had fallen seriously ill from the SARS-CoV-2 virus."

Essential role in the defense

Van der Made and colleagues have investigated the consequences of improper functioning of the TLR7 receptor. "Once activated, TLR7 triggers the production of so-called interferons, signaling proteins that are essential in the defense against virus infections," says van der Made. "This immune response is perhaps all the more important in the fight against the SARS-CoV-2 virus, because we know from the literature that the virus has tricks to reduce the production of interferons by immune cells. When we mimic an infection with the coronavirus, we see that immune cells of the patients without properly functioning TLR7 hardly respond, and that minimal amounts of interferons are produced. These tests make it clear that the virus appears to have free rein in people without properly functioning TLR7 because it [the virus] is not recognized by the immune system."

Consequences

"Due to the serious illness of four brothers in two families, so serious that it cost one of the young men his life, we have discovered this condition," says Hoischen. "It seems to be a very specific abnormality, an immunodeficiency, which is mainly related to this coronavirus. None of the four men have previously suffered from immune-related diseases. It is the first time that we can connect a clinical phenomenon so strongly with TLR7."

"This discovery not only provides us with more insight into the fundamental workings of the immune system, but it may also have important consequences for the treatment of severely ill COVID-19 patients," says Frank van de Veerdonk, immunologist and infectiologist. "The substance interferon can be given as a therapy. It is currently being investigated whether administering interferon in COVID-19 can indeed help."

Living under a translucent rock can be quite comfortable -- if you're a moss in the Mojave Desert.

A graduate student at the University of California, Berkeley, found that some mosses in the California desert seek protection from the relentless sun and heat by sheltering under translucent quartz pebbles, essentially using the rocks as sunshades.

The soil under these rocks retains more moisture than exposed desert soil, said Jenna Ekwealor, while enough light leaks through the milky quartz to allow the tiny mosses to remain green with chlorophyll. Mosses actually prefer dim light, making these conditions ideal for growth. In contrast, nearby mosses in full sun are dried up and black.

One species of desert moss seems able to survive at high elevations only under the milky quartz, which occurs in outcroppings scattered around the desert. Mosses don't grow under granitic stones in the area because sunlight can't get through to the soil.

"We were there (in the Mojave) studying the population biology and reproductive biology of mosses, and picking up these cool quartz rocks, like, oh look at this pretty rock," said Ekwealor, an integrative biology doctoral student who works in the University and Jepson Herbaria at UC Berkeley. While all the other mosses were dry and dormant, she "saw that there was moss growing underneath the quartz and it was bright green. That was the first clue that something was different, that they were responding to the environment differently."

Working with her former master's thesis advisor, Kirsten Fisher of California State University, Los Angeles, they placed temperature and humidity sensors under milky quartz pebbles to record the microclimate from September of last year to February of 2020.

"The rock acts as a buffer for the extremes of the climate," Ekwealor said. "The desert is at a high elevation, it gets really hot in the summer and really cold in the winter. And days can be hot, and nights can be cold. The rock keeps the mosses underneath cooler during the hot parts of the year and warmer during the cold periods. The increased relative humidity was just a positive, an important thing for these plants that dry out when the relative humidity is too low."

Astrobiologists have long studied cyanobacteria that live under translucent desert rocks -- a possible model for the types of extreme life that could exist on other planets -- but this is the first green plant known to take advantage of these natural refuges.

"In the desert, for all organisms, it is like life or death all the time," she said. "So anytime you can find a little boost, a little benefit, it makes a really big difference."

Ekwealor and Fisher reported their discovery this week in the journal PLOS ONE.

Cool mosses

As one of the first land plants to evolve more than 300 million years ago, mosses are well adapted to extreme environments, able to survive repeated desiccation and freezing. Some produce sunscreens to protect against intense ultraviolet sunlight. Some can remain essentially dead, with zero metabolic activity, for a decade, and then revive in seconds when wetted. They're found in the Arctic and Antarctic as well as the hottest, driest deserts.

One of the moss species that often lives under milky quartz, Syntrichia caninervis, typically grows on exposed soil in biocrusts, an association with lichens and cyanobacteria. These crusts are a feature of many deserts, protecting the soil from erosion and providing nutrients for other plants.

As part of the desert's biological crust, Syntrichia are inconspicuous -- about 1 millimeter in diameter and 5 millimeters long. They grow only when wet, and since the Mojave may get only five "precipitation events" per year -- half of which could be snow, which is not conducive to growth -- they grow slowly. Ekwealor estimates that Syntrichia grows only a couple of millimeters per year.

The rest of the time, the Syntrichia mosses on exposed soil remain dormant, turning a dark brown-black, possibly as a sunscreen -- something Ekwealor is trying to figure out for her Ph.D. thesis.

She found that, in contrast to the exposed mosses, mosses that crawl under a rock grow about 60% faster.

"The mosses that normally live at that elevation are small and brown on the soil surface, and under the rocks they are tall and green," she said.

At its lowest, the average relative humidity under the rocks was about twice that of exposed soil -- 63% versus 33%. The daily temperature swing in the "hypolithic microenvironment" was reduced by about 4 degrees Celsius (7 degrees Fahrenheit) from that on the soil surface.

A second moss species, Tortula inermis, grows commonly in full sun at lower altitudes, but at the elevation of the study site, 1,900 meters (6,200 feet), it appears to grow only under milky quartz.

"The rocks offer mosses two big benefits: either a boost in their normal habitat, or they get to live in a habitat that you wouldn't normally live in," Ekwealor said.

Though mosses prefer dim, moist conditions, they, like all plants, require some light or they turn white and die. According to her measurements, between 4% and 0.4% of incident light is transmitted through milky quartz rocks, depending on the size of the rock. At her study site, in a place called Sheep Creek Wash, the quartz ranged in thickness from 25 to 14 millimeters, or an inch to two-fifths of an inch.

The researchers suspect that the quartz not only reduces the overall light and heat, but also provides protection from damaging UV rays. Mosses growing under quartz had less pigmented sunscreen than those growing in exposed areas.

A self-described "moss evangelist," Ekwealor is fascinated by the tiny world of mosses, and occasionally leads local moss walks for the bryophyte chapter of the California Native Plant Society.

"For these tiny plants, a thing like this giant quartz rock over you blocking out all the sun and keeping you wet -- it is like a huge habitat," she said. "You can be in the middle of the desert, but a small rock makes you feel like you are in a spring. We have to remember to see the world from the perspective of a very small plant."

Tiny, 3D-printed bricks have been designed to heal broken bones -- and could one day lead to lab-made organs for human transplant.

Inspired by Lego blocks, the small, hollow bricks serve as scaffolding onto which both hard and soft tissue can regrow better than today's standard regeneration methods, according to new research published in Advanced Materials. Each brick is 1.5 millimeters cubed, or roughly the size of a small flea.

"Our patent-pending scaffolding is easy to use; it can be stacked together like Legos and placed in thousands of different configurations to match the complexity and size of almost any situation," said Luiz Bertassoni, Ph.D., who led the technology's development and is an associate professor in the OHSU School of Dentistry and an associate professor of biomedical engineering in the OHSU School of Medicine.

Bertassoni partnered with colleagues from OHSU, University of Oregon, New York University and Mahidol University in Thailand to develop and evaluate the technology.

When stacked together, the microcages are designed to repair broken bones better than today's methods. Orthopaedic surgeons typically repair more complex bone fractures by implanting metal rods or plates to stabilize the bone and then inserting bio-compatible scaffolding materials packed with powders or pastes that promote healing.

A unique advantage of this new scaffolding system is that its hollow blocks can be filled with small amounts of gel containing various growth factors that are precisely placed closest to where they are needed. The study found growth factor-filled blocks placed near repaired rat bones led to about three times more blood vessel growth than conventional scaffolding material.

"The 3D-printed microcage technology improves healing by stimulating the right type of cells to grow in the right place, and at the right time," said study co-author Ramesh Subbiah, Ph.D., a postdoctoral scholar in Bertassoni's OHSU lab who specializes in growth factor delivery. "Different growth factors can be placed inside each block, enabling us to more precisely and quickly repair tissue."

The small devices are modular and can be assembled to fit into almost any space. When piecing together block segments containing four layers of four-bricks-by-four bricks, the researchers estimate more than 29,000 different configurations can be created.

Bertassoni and colleagues also imagine their 3D-printed technology could be used to heal bones that have to be cut out for cancer treatment, for spinal fusion procedures and to build up weakened jaw bones ahead of a dental implant.

And, by changing the composition of the technology's 3D-printed materials, they envision it could also be used to build or repair soft tissues. With significantly more research, they hope the modular microcage approach could even be used to make organs for transplant.

Bertassoni and his team will further explore the microcages' performance in bone repair. They plan to test the technology's ability to repair more complex bone fractures in rats or larger animals.

If physical distancing measures in the United States are relaxed while there is still no COVID-19 vaccine or treatment and while personal protective equipment remains in short supply, the number of resulting infections could be about the same as if distancing had never been implemented to begin with, according to a UCLA-led team of mathematicians and scientists.

The researchers compared the results of three related mathematical models of disease transmission that they used to analyze data emerging from local and national governments, including one that measures the dynamic reproduction number -- the average number of susceptible people infected by one previously infected person. The models all highlight the dangers of relaxing public health measures too soon.

"Distancing efforts that appear to have succeeded in the short term may have little impact on the total number of infections expected over the course of the pandemic," said lead author Andrea Bertozzi, a distinguished professor of mathematics who holds UCLA's Betsy Wood Knapp Chair for Innovation and Creativity. "Our mathematical models demonstrate that relaxing these measures in the absence of pharmaceutical interventions may allow the pandemic to reemerge. It's about reducing contact with other people, and this can be done with PPE as well as distancing."

The study is published in the journal Proceedings of the National Academy of Sciences and is applicable to both future spikes of COVID-19 and future pandemics, the researchers say.

If distancing and shelter-in-place measures had not been taken in March and April, it is very likely the number of people infected in California, New York and elsewhere would have been dramatically higher, posing a severe burden on hospitals, Bertozzi said. But the total number of infections predicted if these precautions end too soon is similar to the number that would be expected over the course of the pandemic without such measures, she said. In other words, short-term distancing can slow the spread of the disease but may not result in fewer people becoming infected.

Mathematically modeling and forecasting the spread of COVID-19 are critical for effective public health policy, but wide differences in precautionary approaches across the country have made it a challenge, said Bertozzi, who is also a distinguished professor of mechanical and aerospace engineering. Social distancing and wearing face masks reduce the spread of COVID-19, but people in many states are not following distancing guidelines and are not wearing masks -- and the number of infections continues to rise.

What are the implications of these findings for policymakers who want to relax social distancing in an effort to revive their economies?

"Policymakers need to be careful," Bertozzi said. "Our study predicts a surge in cases in California after distancing measures are relaxed. Alternative strategies exist that would allow the economy to ramp up without substantial new infections. Those strategies all involve significant use of PPE and increased testing."

During the 1918 influenza pandemic, social distancing was first enforced and then relaxed in some areas. Bertozzi points to a study published in Proceedings of the National Academy of Sciences in 2007 that looked at several American cities during that pandemic where a second wave of infections occurred after public health measures were removed too early.

That study found that the timing of public health interventions had a profound influence on the pattern of the second wave of the 1918 pandemic in different cities. Cities that had introduced measures early in the pandemic achieved significant reductions in overall mortality. Larger reductions in peak mortality were achieved by those cities that extended the public health measures for longer. San Francisco, St. Louis, Milwaukee and Kansas City, for instance, had the most effective interventions, reducing transmission rates by 30% to 50%.

"Researchers Martin Bootsma and Neil Ferguson were able to analyze the effectiveness of distancing measures by comparing the data against an estimate for what might have happened had distancing measures not been introduced," Bertozzi said of the 2007 study. "They considered data from the full pandemic, while we addressed the question of fitting models to early-time data for this pandemic. During the 1918 influenza pandemic, the early relaxation of social distancing measures led to a swift uptick in deaths in some U.S. cities. Our mathematical models help to explain why this effect might occur today."

The COVID-19 data in the new study are from April 1, 2020, and are publicly available. The study is aimed at scientists who are not experts in epidemiology.

"Epidemiologists are in high demand during a pandemic, and public health officials from local jurisdictions may have a need for help interpreting data," Bertozzi said. "Scientists with relevant background can be tapped to assist these people."

You're faced with a big decision so your second brain provides what's normally referred to as 'gut instinct', but how did this sensation reach you before it was too late?

The Enteric Nervous System (ENS) is an extensive network of neurons and transmitters wrapped in and around the human gut with the prime function of managing digestion, but researchers at Flinders University are delving into the complexity of this brain like system to uncover it's secret capabilities.

In a new study published in the eNeuro journal, Professor Nick Spencer's laboratory has identified a particular type of neuron in the gut wall that communicates signals to other neurons outside the gut, near the spinal cord and up to the brain.

"There is significant interest in how the gut communicates with the brain as a major unresolved issue because of growing evidence that many diseases may first start in the gut and then travel to the brain, an example of which is Parkinson's Disease," says Professor Spencer.

"The new study has uncovered how viscerofugal neurons provide a pathway so our gut can "sense" what is going on inside the gut wall, then relay this sensory information more dynamically than was previously assumed to other organs, like the spinal cord and brain which influence our decisions, mood and general wellbeing."

The results reveal why the ENS might play an increasingly important part on human health, and could shed light on potential new treatments for conditions like Parkinson's disease.

This study represents a big step towards understanding ENS functions and the complexity of the gut and brain connection through the neurons that allow communication in the body.

Professor Spencer says there is increasing interest in understanding how the nervous system in the gut (ENS) communicates with the brain, to give us all those sensations we know of.

"What is particularly exciting about the gut, is that it is unlike all other internal organs (e.g. heart, liver, bladder) because the gut has its own nervous system, which can function independently of the brain or spinal cord. Understanding how the gut communicates and controls other organs in the body can lead to important breakthroughs for disease treatment and this is an important step in the right direction."

What The Article Says: In this essay, an experienced oncologist mourns the loss of personal connection with patients and their families that has resulted from the social distancing of the COVID-19 era.

Authors: Hanna K. Sanoff, M.D., of the University of North Carolina, Chapel Hill, is the corresponding author.

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

(doi:10.1001/jamaoncol.2020.2839)

Editor's Note: Please see the articles for additional information, including other authors, author contributions and affiliations, conflicts of interest and financial disclosures, and funding and support.

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Researchers are urging city-dwellers to switch off their garden lights at night-time after a study of magpies and pigeons revealed the harmful impact artificial light is having on the birds' sleep patterns.

The study by La Trobe University and University of Melbourne, published today in Current Biology, is the first to measure neurological responses to light pollution in wildlife.

The researchers looked at how birds' sleep was affected by artificial white light and the apparently more "sleep-friendly" amber light.

They found light comparable in intensity to street lighting can disrupt the length, structure and intensity of sleep in magpies and pigeons, regardless of the light's colour.

Utilising miniature sensors to measure magpie and pigeon brain activity, researchers found their non-rapid eye movement (NREM) and REM sleep cycles were altered when exposed to white and amber lighting at night, but that the magnitude of these effects differed between the species.

La Trobe University sleep expert Dr John Lesku said that while magpie sleep is more disrupted under white light compared to amber light, both types of light are equally disruptive for sleep in pigeons.

"Both magpies and pigeons average 10 hours of sleep per night. We found that magpies lost more NREM sleep under white light than amber light. By comparison, pigeons lost around 4 hours of sleep under both white and amber light," Dr Lesku said.

"Interestingly, neither species fully recovered sleep lost to white or amber light exposure."

University of Melbourne and La Trobe University researcher Dr Anne Aulsebrook said changes to sleeping patterns in birds, caused by human light pollution, is concerning.

"We know sleep is important for animals to not only function, but thrive," Dr Aulsebrook said.

"While amber lighting appears to have a less damaging impact than white light on magpies, our findings suggest the relative impacts of light pollution on birds may be species-specific. Amber lighting can reduce sleep disruption in some birds, but it is not a solution for all species.

"Additionally, disrupted sleeping patterns that force birds to catch up on sleep in the daytime could impact their ability to forage for food, fight off predators and search for mates."

University of Melbourne and La Trobe University graduate researcher Farley Connelly recommended further research into avian circadian rhythms and the implementation of short-term solutions.

"We should think about using artificial light only as and where it's needed," Mr Connelly said.

"Switch off that porch light, install sensor lights, remove decorative lights from trees, balconies and other outdoor settings, and keep street and park lights directed to the ground or shielded where possible.

"And if you're ever woken by the early call of a magpie, remember it could be just as sleep deprived as you are."

Throughout history, spikes in mortality due to wars and famines were followed by increased births, while the Spanish Flu resulted in a temporary drop in fertility before recovering during a "baby boom." Contrary to this historic trend, the Covid-19 health emergency will plausibly cause a decline in fertility, without the factors that have brought on a baby boom in the past, according to "The Covid-19 pandemic and human fertility" published on July 24 by Science Magazine, the peer-reviewed journal of the American Association for the Advancement of Science, by Bocconi University's Arnstein Aassve, Nicolò Cavalli, Letizia Mencarini and Samuel Plach, and Massimo Livi Bacci from University of Florence.

The authors emphasize differences in populations' development and their stage in the demographic transition to accurately draw conclusions from the existing research.

"Although it is difficult to make precise predictions, a likely scenario is that fertility will fall, at least in high-income countries and in the short run," said Arnstein Aassve, Professor at the Department of Social and Political Sciences at Bocconi and at the Carlo F. Dondena Centre for Research on Social Dynamics and Public Policy.

This study is part of the Dondena Centre's research activities within Bocconi's Covid Crisis Lab.

In high-income countries, disruption in the organization of family life due to prolonged lockdowns, the reinternalization of childcare within the couple following school closures, and deteriorating economic outlooks are likely to lead to postponements in childbearing. A further fertility fall in high-income countries will accelerate population ageing and population decline, with implications for public policy.

In low- and middle-income countries the fertility decline observed in recent decades from trends such as urbanization, economic development and female occupation is unlikely to be fundamentally reversed by economic setbacks. Difficulties, though, in accessing family planning services might result in a short-run spike in unintended pregnancies and worsening neonatal and reproductive health.

Home-made cloth face masks likely need a minimum of two layers, and preferably three, to prevent the dispersal of viral droplets from the nose and mouth that are associated with the spread of COVID-19, indicates a video case study published online in the journal Thorax.

Viral droplets are generated during coughing, sneezing, or speaking. And face masks are thought to protect healthy people from inhaling infectious droplets as well as reducing the spread from those who are already infected.

But worldwide shortages of personal protective equipment during the pandemic have led some health agencies, such as the US Centers for Disease Control (CDC), to recommend the use of home-made cloth face coverings as an alternative to surgical face masks.

Several types of material have been suggested for these, but based on little or no evidence of how well they work.

A team of Australian researchers therefore compared the effectiveness of single and double-layer cloth face coverings (175 g/m² cotton fabric, with a thread count of 170/ inch) with a 3-ply surgical face mask (Bao Thach) at reducing droplet spread.

The single layer covering was made from a folded piece of cotton T shirt and hair ties; the double layer covering was made using the sew method, as set out by CDC:
https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/how-to-make-cloth-face-covering.html

The researchers used a tailored LED lighting system and a high-speed camera to film the dispersal of airborne droplets produced by a healthy person with no respiratory infection, during speaking, coughing, and sneezing while wearing each type of mask.

The video recording showed that the 3-ply surgical face mask was the most effective at reducing airborne droplet dispersal, although even a single layer cloth face covering reduced the droplet spread from speaking.

But a double layer covering was better than a single layer in reducing the droplet spread from coughing and sneezing, the recording showed.

This is just one case, added to which several other factors contribute to the effectiveness of cloth face masks, note the researchers. These include the type of material used, design and fit, as well as the frequency of washing.

Nevertheless, based on their observations, a home made cloth mask with at least two layers is preferable to a single layer mask, they say, adding: "Guidelines on home-made cloth masks should stipulate multiple layers."

And they emphasise: "There is a need for more evidence to inform safer cloth mask design, and countries should ensure adequate manufacturing or procurement of surgical masks."

This quiet period, likely caused by the total global effect of social distancing measures, closure of services and industry, and drops in tourism and travel, is the longest and most pronounced quiet period of seismic noise in recorded history.

The new research, led by the Royal Observatory of Belgium and five other institutions around the world including Imperial College London, showed that the dampening of 'seismic noise' caused by humans was more pronounced in more densely populated areas.

The relative quietness allowed researchers to listen in to previously concealed earthquake signals, and could help us differentiate between human and natural seismic noise more clearly than ever before.

Co-author Dr Stephen Hicks, from Imperial's Department of Earth Science and Engineering, said: "This quiet period is likely the longest and largest dampening of human-caused seismic noise since we started monitoring the Earth in detail using vast monitoring networks of seismometers.

"Our study uniquely highlights just how much human activities impact the solid Earth, and could let us see more clearly than ever what differentiates human and natural noise."

The paper is published today in Science.

Anthropause

Measured by instruments called seismometers, seismic noise is caused by vibrations within the Earth, which travel like waves. The waves can be triggered by earthquakes, volcanoes, and bombs - but also by daily human activity like travel and industry.

Although 2020 has not seen a reduction in earthquakes, the drop in human-caused seismic noise is unprecedented. The strongest drops were found in urban areas, but the study also found signatures of the lockdown on sensors buried hundreds of metres underground and in more remote areas.

Human-generated noise usually dampens during quiet periods like over the Christmas/New Year period and Chinese New Year, and during weekends and overnight. However, the drop in vibrations caused by COVID-19 lockdown measures eclipse even those seen during these periods.

Some researchers are dubbing this drop in anthropogenic (human-caused) noise and pollution the 'anthropause'.

Dr Hicks said: "This is the first global study of the impact of the coronavirus anthropause on the solid Earth beneath our feet."

To gather the data, researchers looked at seismic data from a global network of 268 seismic stations in 117 countries and found significant noise reductions compared to before any lockdown at 185 of those stations. Beginning in China in late January 2020, and followed by Europe and the rest of the world in March to April 2020, researchers tracked the 'wave' of quietening between March and May as worldwide lockdown measures took hold.

The largest drops in vibrations were seen in the most densely populated areas, like Singapore and New York City, but drops were also seen in remote areas like Germany's Black Forest and Rundu in Namibia.
Citizen-owned seismometers, which tend to measure more localised noise, noted large drops around universities and schools around Cornwall, UK and Boston, USA - a drop in noise 20 per cent larger than seen during school holidays.
Countries like Barbados, where lockdown coincided with the tourist season, saw a 50 per cent decrease in noise. This coincided with flight data that suggested tourists returned home in the weeks before official lockdown.

Listening in

Over the past few decades, seismic noise has gradually increased as economies and populations have grown.

The drastic changes to daily life caused by the pandemic have provided a unique opportunity to study their environmental impacts, such as reductions in emissions and pollution in the atmosphere. The changes have also given us the opportunity to listen in to the Earth's natural vibrations without the distortions of human input.

The study reports the first evidence that previously concealed earthquake signals, especially during daytime, appeared much clearer on seismometers in urban areas during lockdown.

The researchers say the lockdown quietening could also help them differentiate between human-caused noise and natural signals that might warn of upcoming natural disasters.

Lead author Dr Thomas Lecocq from the Royal Observatory of Belgium said: "With increasing urbanisation and growing global populations, more people will be living in geologically hazardous areas. It will therefore become more important than ever to differentiate between natural and human-caused noise so that we can 'listen in' and better monitor the ground movements beneath our feet. This study could help to kick-start this new field of study."

The study's authors hope that their work will spawn further research on the seismic lockdown, as well as finding previously hidden signals from earthquakes and volcanoes.

Dr Hicks said: "The lockdowns caused by the coronavirus pandemic may have given us a glimmer of insight into how human and natural noise interact within the Earth. We hope this insight will spawn new studies that help us listen better to the Earth and understand natural signals we would otherwise have missed."

A new 42-country study has found that the more gender egalitarian the country, the less likely men are to support women's causes.

The study, published in the European Journal of Social Psychology, was led by Dr Natasza Kosakowska-Berezecka from the University of Gda?sk, Poland, and involved a team of experts including Dr Magdalena Zawisza of Anglia Ruskin University (ARU), who was a member of the lead research group.

Gender equality benefits both men and women at individual and society levels. It is associated with greater human rights observance, higher levels of happiness and wellbeing, and better physical and mental health, in addition to greater relationship satisfaction and economic benefits, including higher average levels of GDP.

The new research is the largest study on this topic ever undertaken, forming part of the Towards Gender Harmony project, and involved 6,734 men from 42 nations ranging from Norway, ranked second out of 153 countries for gender equality in the World Economic Forum's 2020 Global Gender Gap Index (GGGI) to Pakistan, ranked 151st.

The researchers found, regardless of nationality, that the more men believe in "zero-sum" thinking - that gains for women equate to losses for men - the less they are inclined to support gender equality and are more likely to express attitudes of hostile sexism.

Counterintuitively, the study also found that the higher the national level of gender egalitarianism, the less men are willing to engage in activities such as signing petitions in favour of workplace gender equality, endorsing gender egalitarian political candidates, and using social media to raise awareness about gender issues. Norway, the Philippines, and Ireland were the most egalitarian countries (according to their GGGI scores) included in this study.

Dr Zawisza, Reader in Consumer and Gender Psychology at Anglia Ruskin University (ARU), said: "Some men view women as competitors rather than allies, and our research found that men, regardless of their nationality, withdraw their support for gender equality when they think that women's gains threaten their own status.

"What is particularly interesting is that higher levels of gender equality within a country appear to have the effect of demotivating men from supporting gender equality causes. This could be due to a perceived threat to men's masculinity or men's belief that women are doing perfectly well on their own and do not need any extra help.

"Although we are seeing more women in senior management and executive roles, globally women earn 21% less than men and hold only 29% of the positions of power. This 'zero-sum' thinking, where gains for women equate to losses for men, remains a key barrier to further improvements in equality. Instead, 'her gain equals his gain' thinking needs to be promoted if we are to move towards gender harmony."

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Leesburg, VA, July 23, 2020--According to an open-access article published in ARRS' American Journal of Roentgenology (AJR), lung ultrasound (US) was highly sensitive for detecting abnormalities in patients with coronavirus disease (COVID-19), with B-lines, a thickened pleural line, and pulmonary consolidation the most commonly observed features.

"In addition," concluded Yao Zhang of at China's Beijing Ditan Hospital, "our results indicate that lung US findings can be used to reflect both the infection duration and disease severity."

From March 3 to March 30, 2020, Zhang and colleagues performed lung US on consecutive patients with positive reverse transcriptase polymerase chain reaction (RTPCR) test results for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), using the Fisher exact test to compare the percentages of patients with each US finding between groups with different symptom durations and disease severity.

All 28 patients (14 men and 14 women; age range, 21-92 years) had positive findings on both lung US and chest CT. On US, B-lines were present in 100% of patients, and 19 (67.9%) patients had pulmonary consolidation. Thickened pleural lines were observed in 17 patients (60.7%), and only one patient (3.6%) showed a small amount of pleural effusion.

"A thickened pleural line was more frequently observed on US in patients with longer time intervals after the initial onset of symptoms," Zhang et al. noted, adding that pulmonary consolidations--visualized as tissuelike hypoechoic regions, reflecting highly reduced air flow and increased quantity of inflammatory cellular exudate--were more common in severe and critical cases.

Acknowledging that portable radiography could be just as useful in evaluating consolidation, "a bedside portable, handheld US system or even a robot-assisted tele-US system (a unique technique for physicians to remotely scan patients) further minimizes the number of health care workers and medical devices exposed to COVID-19," wrote Zhang and team.

The authors of this AJR article also proposed that severity scoring for lung US, similar to CT severity scores, should be developed to facilitate more accurate comparisons in future studies.

The latest AJR Podcast episode takes a closer look at "Lung US Findings in Coronavirus Disease-19 (COVID-19) Patients," noting that compared to CT, US is portable, less costly, and does not use radiation--making US a useful tool for triage, particularly in pre-hospital/outpatient settings, and severity stratification and monitoring, especially for critically ill patients who may be challenging to transport and require careful ventilation management:

https://ajrpodcast.libsyn.com/lung-us-findings-in-coronavirus-disease-19-covid-19-patients

Juvenile fishes have one of the highest mortality rates compared to other life stages. Within two days of settling into a reef almost 60 percent are consumed by predators. Our recent study found noisy boats and ships can also affect the prey response of these young fishes.

When exposed to the noise of vessels, juvenile fishes decreased their activity, which reduced their swimming distance. Previous research found more active fishes learn faster about their environment and potential predators, which results in a higher chance of survival (2).

We also found juveniles exposed to boat and ship noise were slower to escape when exposed to a simulated predator attack. This is highly relevant as the timing of the escape response to a predator is critical for success--a slower fish is more likely to get eaten.

Noise pollution is mostly concentrated in coastal areas. The higher the human population the higher the incidence of recreational boating activities such as diving and recreational fishing. More than 250,000 boats are registered in the Great Barrier Reef region and this number is projected to increase 500 percent by 2040. This means vessel noise is not only already widespread, but increasing along the Great Barrier Reef.

Our results suggest boat and ship noise could increase the mortality of juvenile fishes during their critical period of growth (and remember, ~60 percent already die within two days). In areas such as the Great Barrier Reef, fishes are likely exposed to recreational boats and ships multiple times throughout their life. An increase in the mortality rate could have implications for population structure and community dynamics.

Man-made noise is easier to manage compared to other pollutants, which provides an opportunity to mitigate its effects on coral reef communities. The main goal of our research is to investigate the effects of noise on reef fishes in order to provide governmental institutions with information for its management and regulation. Future research will investigate the long-term effects of noise pollution on fishes and whether there are interactive effects with other stressors.