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Below please find a summary and link(s) of new coronavirus-related content published today in Annals of Internal Medicine. The summary below is not intended to substitute for the full article as a source of information. A collection of coronavirus-related content is free to the public at http://go.annals.org/coronavirus.

1. Hydroxychloroquine shows no benefit to patients with early, mild COVID-19 in randomized trial

Full text: https://www.acpjournals.org/doi/10.7326/M20-4207

Editorial: https://www.acpjournals.org/doi/10.7326/M20-5041

In a randomized trial, hydroxychloroquine did not substantially reduce symptom severity in outpatients with early, mild COVID-19. These findings may not inform whether an effect would be observed in populations at higher risk for severe COVID-19. Results from a randomized clinical trial are published in Annals of Internal Medicine.

Currently, there are no effective treatments for COVID-19. The majority of previous clinical studies investigating therapies for COVID-19 were small in size and examined hospitalized patients with moderate to severe disease.

Researchers from the University of Minnesota hypothesized that starting hydroxychloroquine within the first few days of symptoms could alter the course of COVID-19 by reducing symptom severity, symptom duration, and preventing hospitalizations. They randomly assigned symptomatic, non-hospitalized adults with lab-confirmed or probable COVID-19 to either oral hydroxychloroquine 800 mg once, followed by 600 mg in 6-8 hours, then 600mg daily for 4 more days, or masked placebo. Of 423 patients with available end-point data, 82 percent had lab-confirmed infection, and 56 percent were enrolled within 1 day of symptoms starting. Change in symptom severity over 14 days did not differ between hydroxychloroquine and placebo groups. At 14 days, 24 percent receiving hydroxychloroquine had ongoing symptoms compared with 30 percent receiving placebo. Side effects were mild, but more common with hydroxychloroquine than with placebo. The researchers note that the study was limited by severe U.S. testing shortages. Only 58 percent of participants received SARS-COV-2 testing.

The author of an accompanying editorial from New York Medical College calls the saga of hydroxychloroquine and COVID-19 a cautionary tale. Research standards should not be lowered during a pandemic. These findings, taken together with other published randomized controlled trials, provide strong evidence that hydroxychloroquine offers no benefit in patients with mild illness. If the peer-reviewed findings confirm the preliminary reports of no benefit in sicker patients in the National Institutes of Health and RECOVERY trials, the saga of hydroxychloroquine and COVID-19 will likely reach its sad end, the author writes.

Media contacts: PDFs for these articles are not yet available. Please click the links above to read full text. The lead authors, Caleb P Skipper MD or David R. Boulware MD MPH, can be reached through Kelly Glynn at glynn040@umn.edu. The editorialist, Neil W. Schluger, MD can be reached at nschluge@nymc.edu.

The first images from ESA/NASA's Solar Orbiter are now available to the public, including the closest pictures ever taken of the Sun.

Solar Orbiter is an international collaboration between the European Space Agency, or ESA, and NASA, to study our closest star, the Sun. Launched on Feb. 9, 2020 (EST), the spacecraft completed its first close pass of the Sun in mid-June.

"These unprecedented pictures of the Sun are the closest we have ever obtained," said Holly Gilbert, NASA project scientist for the mission at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "These amazing images will help scientists piece together the Sun's atmospheric layers, which is important for understanding how it drives space weather near the Earth and throughout the solar system."

"We didn't expect such great results so early," said Daniel Müller, ESA's Solar Orbiter project scientist. "These images show that Solar Orbiter is off to an excellent start."

Getting to this point was no simple feat. The novel coronavirus forced mission control at the European Space Operations Center, or ESOC, in Darmstadt, Germany to close down completely for more than a week. During commissioning, the period when each instrument is extensively tested, ESOC staff were reduced to a skeleton crew. All but essential personnel worked from home.

"The pandemic required us to perform critical operations remotely - the first time we have ever done that," said Russell Howard, principal investigator for one of Solar Orbiter's imagers.

But the team adapted, even readying for an unexpected encounter with comet ATLAS's ion and dust tails on June 1 and 6, respectively. The spacecraft completed commissioning just in time for its first close solar pass on June 15. As it flew within 48 million miles of the Sun, all 10 instruments flicked on, and Solar Orbiter snapped the closest pictures of the Sun to date. (Other spacecraft have been closer, but none have carried Sun-facing imagers.)

Solar Orbiter carries six imaging instruments, each of which studies a different aspect of the Sun. Normally, the first images from a spacecraft confirm the instruments are working; scientists don't expect new discoveries from them. But the Extreme Ultraviolet Imager, or EUI, on Solar Orbiter returned data hinting at solar features never observed in such detail.

Principal investigator David Berghmans, an astrophysicist at the Royal Observatory of Belgium in Brussels, points out what he calls "campfires" dotting the Sun in EUI's images.

"The campfires we are talking about here are the little nephews of solar flares, at least a million, perhaps a billion times smaller," Berghmans said. "When looking at the new high resolution EUI images, they are literally everywhere we look."

It's not yet clear what these campfires are or how they correspond to solar brightenings observed by other spacecraft. But it's possible they are mini-explosions known as nanoflares - tiny but ubiquitous sparks theorized to help heat the Sun's outer atmosphere, or corona, to its temperature 300 times hotter than the solar surface.

To know for sure, scientists need a more precise measurement of the campfires' temperature. Fortunately, the Spectral Imaging of the Coronal Environment, or SPICE instrument, also on Solar Orbiter, does just that.

"So we're eagerly awaiting our next data set," said Frédéric Auchère, principal investigator for SPICE operations at the Institute for Space Astrophysics in Orsay, France. "The hope is to detect nanoflares for sure and to quantify their role in coronal heating."

Other images from the spacecraft showcase additional promise for later in the mission, when Solar Orbiter is closer to the Sun.

The Solar and Heliospheric Imager, or SoloHI, led by Russell Howard of the Naval Research Laboratory in Washington, D.C., revealed the so-called zodiacal light, light from the Sun reflecting off of interplanetary dust - a light so faint that the bright face of the Sun normally obscures it. To see it, SoloHI had to reduce the Sun's light to one trillionth of its original brightness.

"The images produced such a perfect zodiacal light pattern, so clean," Howard said. "That gives us a lot of confidence that we will be able to see solar wind structures when we get closer to the Sun."

Images from the Polar and Helioseismic Imager, or PHI, showed it is also primed for later observations. PHI maps the Sun's magnetic field, with a special focus on its poles. It will have its heyday later in the mission as Solar Orbiter gradually tilts its orbit to 24 degrees above the plane of the planets, giving it an unprecedented view of the Sun's poles.

"The magnetic structures we see at the visible surface show that PHI is receiving top-quality data," said Sami Solanki, PHI's principal investigator at the Max Planck Institute for Solar System Research in Göttingen, Germany. "We're prepared for great science as more of the Sun's poles comes into view."

Today's release highlights Solar Orbiter's imagers, but the mission's four in situ instruments also revealed initial results. In situ instruments measure the space environment immediately surrounding the spacecraft. The Solar Wind Analyser, or SWA instrument, shared the first dedicated measurements of heavy ions (carbon, oxygen, silicon, iron, and others) in the solar wind from the inner heliosphere.

They occur in nature, are reactive and play a role in many biological processes: polyenes. It is no wonder that chemists have for a long time been interested in efficiently constructing these compounds - not least in order to be able to use them for future biomedical applications. However, such designs are currently neither simple nor inexpensive and present organic chemists with major challenges. Scientists at the University of Münster (Germany) headed by Prof. Ryan Gilmour have now found a bio-inspired solution to the problem: They succeeded in constructing complex polyenes such as retinoic acid from simple, geometrically well-defined alkene building blocks. To do this, the scientists used small molecules as "antennas" which they excited with light, thereby enabling difficult chemical reactions to proceed via a process known as "Energy Transfer Catalysis".

"The process provides us with a light-driven, operationally simple solution to a conundrum that has occupied us for a long time," says Dr. John J. Molloy, the first author of the study. The new possibility of forming complex polyenes could facilitate the exploration of these bioactive materials for drug discovery. The study has been published in the journal "Science".

Background and method:

The alkenes used by the scientists are structural units that can exist in two non-equivalent geometrical forms. These so-called stereoisomers - i.e. compounds in which the bonding pattern is the same but which differ in the spatial arrangement of the atoms - are a valuable source of chemical information in biology and are common structural features in larger complex molecules such as retinal, a vitamin A derivative. Although, alkene geometry plays a pivotal role in function, e.g. regulating the mammalian visual cycle, strategies to access geometrically defined alkene building blocks for iterative synthesis are conspicuously underdeveloped. Although many methods exist to access each isomer independently, they are often plagued by poor selectivity or require laborious independent synthesis campaigns.

Much as plants convert light to energy, the researchers harnessed small, inexpensive organic molecules under irradiation to "flip" common alkene building blocks into the more challenging form. This process is termed "energy transfer catalysis".

Since these materials are functionalised at both sites, they could be iteratively extended to construct complex bioactive polyenes such as retinoic acid, which may exist in multiple forms by virtue of alkene stereoisomerism. The Münster team demonstrated the power of their method in short, stereocontrolled syntheses of two retinoic acid-based drugs Isotretinoin and Alitretinoin.

The new method combines the importance of carbonyl chemistry in biosynthesis with the versatility of organoboron motifs in contemporary organic chemistry. "This article is dedicated to Prof. Duilio Arigoni, who recently passed away. He was a pioneer in bio-organic chemistry with whom I had the pleasure to work with in Zürich years ago and he often highlighted the urgency of this problem. This innovative solution is testimony to the hard work, innovation a dedication of a very talented group of highly motivated co-workers," says Ryan Gilmour.

Deep in the inky ocean abyss off the coast of British Columbia, reefs made of glass sea sponges cover hundreds of kilometres of the ocean floor. The sponges form multi-storied habitats, their glass skeletons stacked on top of one another to create intricate reefs. And while their description may sound otherworldly, these reefs are home to creatures with whom we are very familiar, including halibut, rockfish, and shrimp.

In February 2017, Fisheries and Oceans Canada designated this region--including Hecate Strait and Queen Charlotte Sound--a marine protected area in order to preserve the delicate, glass reefs. But to effectively manage conservation efforts, scientists must develop a better understanding of the lifeforms that are already there.

"One of the most important reasons for studying the diversity of sea sponges in our oceans is for conservation management," explained Lauren Law, who conducted this research as part of her graduate studies with Sally Leys, professor in the University of Alberta's Department of Biological Sciences. "Many studies in the protected area have focused on describing the crustaceans and fish living in the reefs, but non-reef forming sponges remain overlooked."

Now, the UAlberta research team has published a study on the discovery of a new sponge that is abundant in the region, making up nearly 20 per cent of the live sponges in the reefs off the coast of British Columbia. The new species--called Desmacella hyalina--was discovered using an underwater robot that travelled along the ocean floor, surveying reefs and collecting samples.

"Our findings show Desmacella comprise a surprisingly large amount of live sponge cover in the reefs and can have potential major influence on reef function, recruitment, and overall ecosystem health," said Law, who is now a biologist with Fisheries and Oceans Canada Pacific Region. "While we have discovered a new species, we have yet to determine its relationship with glass sponges in the area."

The researchers recommend further investigation to better understand the role of Desmacella in the ecosystem, as well as more ecological assessment of glass sponge habitat focused on surveying non-reef forming sponges.

"Properly knowing the components of an environment and the linkages between them--here this new species Desmacella hyalina and the reef sponges it lives on--is a major step forward in understanding the ecosystem services and function of the sponge reefs," added Leys. "This is the information we need for concrete management strategies."

For decades, researchers have looked for ways to eliminate cobalt from the high-energy batteries that power electronic devices, due to its high cost and the human rights ramifications of its mining. But past attempts haven't lived up to the performance standards of batteries with cobalt.

Researchers from the Cockrell School of Engineering at The University of Texas at Austin say they've cracked the code to a cobalt-free high-energy lithium-ion battery, eliminating the cobalt and opening the door to reducing the costs of producing batteries while boosting performance in some ways. The team reported a new class of cathodes -- the electrode in a battery where all the cobalt typically resides -- anchored by high nickel content. The cathode in their study is 89% nickel. Manganese and aluminum make up the other key elements.

More nickel in a battery means it can store more energy. That increased energy density can lead to longer battery life for a phone or greater range for an electric vehicle with each charge.

The findings appeared this month in the journal Advanced Materials. The paper was written by Arumugam Manthiram, a professor in the Walker Department of Mechanical Engineering and director of the Texas Materials Institute, Ph.D. student Steven Lee and Ph.D. graduate Wangda Li.

Typically, increased energy density leads to trade-offs, such as a shorter cycle life -- the number of times a battery can be charged and discharged before it loses efficiency and can no longer be fully charged. Eliminating cobalt usually slows down the kinetic response of a battery and leads to lower rate capability -- how quickly the cathode can be charged or discharged. However, the researchers said they've overcome the short cycle life and poor rate capability problems through finding an optimal combination of metals and ensuring an even distribution of their ions.

Most cathodes for lithium-ion batteries use combinations of metal ions, such as nickel-manganese-cobalt (NMC) or nickel-cobalt-aluminum (NCA). Cathodes can make up roughly half of the materials costs for the entire battery, with cobalt being the priciest element. At a price of approximately $28,500 per ton, it is more expensive than nickel, manganese and aluminum combined, and it makes up 10% to 30% of most lithium-ion battery cathodes.

"Cobalt is the least abundant and most expensive component in battery cathodes," Manthiram said. "And we are completely eliminating it."

The key to the researchers' breakthrough can be found at the atomic level. During synthesis, they were able to ensure the ions of the various metals remained evenly distributed across the crystal structure in the cathode. When these ions bunch up, performance degrades, and that problem has plagued previous cobalt-free, high-energy batteries, Manthiram said. By keeping the ions evenly distributed, the researchers were able to avoid performance loss.

"Our goal is to use only abundant and affordable metals to replace cobalt while maintaining the performance and safety," Li said, "and to leverage industrial synthesis processes that are immediately scalable."

Manthiram, Li and former postdoctoral researcher Evan Erickson worked with UT's Office of Technology Commercialization to form a startup called TexPower to bring the technology to market. The researchers have received grants from the U.S. Department of Energy, which has sought to decrease dependency on imports for key battery materials.

Industry has jumped on the cobalt-free push -- most notably an effort from Tesla to eliminate the material from the batteries that power its electric vehicles. With large government organizations and private companies focused on reducing dependence on cobalt, it's no surprise that this pursuit has become competitive. The researchers said they have avoided problems that hindered other attempts at cobalt-free, high-energy batteries with innovations on the right combination of materials and the precise control of their distribution.

"We are increasing the energy density and lowering the cost without sacrificing cycle life," Manthiram said. "This means longer driving distances for electric vehicles and better battery life for laptops and cellphones."

The past is often the window to our future, especially when it comes to natural disasters. Using data from the 2018 floods that struck southwestern Japan to calibrate a machine learning model, researchers from the International Research Institute of Disaster Science (IRIDeS) at Tohoku University and the Japan-Peru Center for Earthquake Engineering Research and Disaster Mitigation (CISMID, in Spanish), have successfully identified the flooding caused by Typhoon Hagibis.

Typhoon Hagibis devastated Japan in October 2019, killing 91 people, damaging 85,000 homes, and causing approximately $15 billion in damage. Flooding across the affected regions was profound.

In natural disaster rescue and recovery efforts, real-time flood mapping is crucial. It allows governments to direct relief to the areas that need it most. To aid this effort, satellite images using artificial intelligence (AI) are often employed.

Crucial to this is training data. Training data allows the algorithms to learn data and produce outputs when new inputs arise in a process known as machine learning. However, the amount of training data is limited in many cases. Collecting training data immediately following a disaster is costly, time-consuming and many times impossible.

At IRIDeS and CISMID, authors of the study, evaluated the performance of a model to learn from the 2018 floods that struck southwestern Japan, and to identify the floods induced by the 2019 Typhoon Hagibis. The resulting flood maps were consistent with the results of actual flooding maps released by local governments and public institutions.

The authors note that "Our model successfully identifies the inundated areas and verified that AI can learn from past disasters, ultimately allowing us to better predict flooding in future events." They add that "Our next step in this project would be to incorporate data from the unknown event into a second stage of training for a more accurate estimation."

Acting like an invisible force field, a new liquid coating being developed by UBC Okanagan researchers may provide an extra layer of protection for front-line workers.

Researchers at the Okanagan Polymer Engineering Research and Applications (OPERA) Lab have developed a coating that repels nearly all substances off a surface. And that new coating will make cleaning personal protective equipment a little bit easier for front-line health care workers, explains Kevin Golovin, an assistant professor at UBCO's School of Engineering and director at OPERA.

Surfaces that can repel a broad range of liquids are called omniphobic, explains UBCO master's student and lead author of the study Behrooz Khatir. Working in Golovin's lab, Khatir has created a spray-on solution that can make any surface, including a face shield, omniphobic.

"Omniphobic--all-liquid repellent--films can repel a broad range of liquids, but the applicability of these coatings has always been limited to silicon wafers or smooth glass," says Khatir. "This new formulation can coat and protect just about any surface, including metals, paper, ceramics and even plastics."

The two-layer coating involves placing an ultra-smooth silica layer on a surface and then functionalizing this layer with a highly-reactive silicone to effectively block all kinds of liquids from sticking on the surface, explains Golovin.

Not only does the coating repel countless substances, but even under harsh exposures like UV light, acids and high temperatures, the coating maintains its resistance qualities. And Golovin notes, if the coating does become damaged it can be easily and repeatedly repaired, fully restoring the omniphobic properties to their initial state.

Golovin recently received COVID-19 funding from the Natural Sciences and Engineering Research Council (NSERC) to optimize the coating for health care face shields so they stay clean, in partnership with Kelowna-based survivability products manufacturer PRE Labs Inc.

"This technology has many applications, but we are currently focused on providing a solution that will keep our nurses and doctors safe and effective," says Golovin. "This new coating will prevent droplets or microbes from sticking to a face shield. This makes disinfecting face shields feasible just with water rather than requiring complex disinfectant procedures."

The original research was recently published in the ACS Applied Materials & Interfaces journal, with funding support from NSERC.

California may see a 54 percent increase in rainfall variability by the end of this century, according to new research from the lab of Assistant Professor Da Yang, a 2019 Packard Fellow and atmospheric scientist with the University of California, Davis.

Writing in the journal Nature Climate Change, Yang and his co-authors predict the entire West Coast will experience greater month-to-month fluctuations in extremely dry and wet weather, especially in California. The lead author is Wenyu Zhou, a postdoctoral researcher in the Lawrence Berkeley National Laboratory where Yang has a dual appointment.

The study explores the Madden-Julian oscillation (MJO), an atmospheric phenomenon that influences rainfall in the tropics and can trigger everything from cyclones over the Indian Ocean to heatwaves, droughts and flooding in the United States. Yang, Zhou and their team show that as the Earth's climate warms, the dynamics controlling MJO will expand eastward and cause a huge uptick in extreme weather in California.

"I was surprised by the magnitude of the effect," said Yang, an assistant professor with the UC Davis Department of Land, Air and Water Resources. "A 54 percent increase in rainfall variability will have very significant impacts on agriculture, flood control and water management."

In 2019, Yang was among 22 early-career scientists and engineers nationwide to receive the prestigious Packard Fellowship. He is the first recipient of the award for the UC Davis College of Agricultural and Environmental Sciences.

This study was supported by the David and Lucille Packard Foundation and by the project "Toward Accurately Predicting California Hydroclimate by Cracking the Tropical Storm King," which is funded by the U.S. Department of Energy.

Yang and his team use satellite observations and computer models to study the physics of rainstorms and atmospheric circulation in a changing climate. They are working to understand what environmental factors control the size and duration of rainstorms and how the collective effects of rainstorms, in turn, shape Earth's climate.

A research led by the Department of Geography at Hong Kong Baptist University (HKBU) has revealed that the observed average moving speed (or translation speed) of tropical cyclones making landfall over the coast of China dropped by 11% between 1961 and 2017. These slow-moving tropical cyclones brought about 20% more local total rainfall on average when compared with fast-moving ones, resulting in greater flood risks in the region.

The study also found that the occurrence of tropical cyclones with lower moving speeds and higher total rainfalls became more frequent after 1990 in the Pearl River Delta. The discovery offers invaluable insights that will enable the development of better flood management and adaptation strategies in the coastal region of China which is under threat due to tropical cyclones.

Over 400 tropical cyclones under study

The research team led by Dr Li Jianfeng, Assistant Professor of the Department of Geography at HKBU, studied 406 tropical cyclones which made landfall and lasted for more than two days over the coast of China, and specifically the Pearl River Delta where Hong Kong is located, between 1961 and 2017. The study, which started in 2018, aimed to investigate the trend of tropical cyclones' moving speeds and its correlation with the volume of rainfall in the long run.

The research team analysed track data of the 406 tropical cyclones from the International Best Track Archive for Climate Stewardship (IBTrACS) and numerical simulations of eight Global Climate Models (GCMs) developed by meteorological and modelling centres around the world. IBTrACS is one of the most commonly used datasets for tropical cyclone studies, while GCMs are important tools for scientific communities to investigate and project climate behaviour.

Tropical cyclone's moving speed correlates negatively with local rainfall volume

The team found that the observed moving speed of the tropical cyclones underwent a significant drop of 11%, decreasing from 21 km per hour in 1961 to 18.6 km per hour in 2017. The simulated moving speed also showed a drop of 10%, decreasing from 21.2 km per hour to 19.1 km per hour during the same period.

Data on the volume of local rainfall brought about by the 406 tropical cyclones was also examined. While the mean total volume of local rainfall increased by 8% between 1961 and 2017, the 90th percentile of the total volume of local rainfall increased even more significantly by 18%, rising from 187 mm to 223 mm. As a result, the data indicated an increase in extreme rainfall caused by tropical cyclones over the 57-year period examined.

Using statistical analysis, the team detected a negative correlation between the moving speeds of the tropical cyclones and their volume of local rainfall. The mean volume of local rainfall of slow-moving tropical cyclones with moving speeds of 15 km per hour or below was 99.1 mm, while that of fast-moving tropical cyclones with moving speeds of 25 km per hour or above was 80.5 mm. In other words, slow-moving tropical cyclones brought about 20% more rainfall on average when compared with fast-moving ones.

"The total amount of rainfall over a specific region brought about by a tropical cyclone is directly proportional to rainfall intensity, and inversely proportional to moving speed. The slower a tropical cyclone moves, the longer it spends passing over the region. As the region is affected for a longer duration, slower tropical cyclones bring about more rainfall," said Dr Li.

Slow-moving tropical cyclones more frequent since 1990

The study further examined the correlation between the moving speeds of tropical cyclones and total rainfall in the Pearl River Delta. Among the 147 tropical cyclones that affected the Pearl River Delta between 1961 and 2017, 14 of them were slow-moving and had a rainfall intensity of 30 mm per day or more. Ten of them occurred after 1990, including three with a total volume of rainfall of more than 200 mm, indicating a substantial increase of flood risks caused by slow-moving tropical cyclones in recent years.

Among the 406 tropical cyclones examined in this study, 82 affected Hong Kong and moved within 200 km of the city. Out of these 82 tropical cyclones, 22 were slow-moving, and 14 of them (about 64%) occurred after 1990. They include Typhoon York in 1999 and Severe Tropical Storm Goni in 2009 which caused extensive damage in the region.

More holistic flood risk management strategies needed

"With analysis backed by long-term observations, we have provided evidence showing that slower tropical cyclone movement tends to elevate rainfall volume and thus it imposes greater flood risks at a regional scale. Therefore, more holistic and integrated flood risk management strategies, as well as flexible adaptation options, will be needed to deal with the growing threat of floods," said Dr Li.

The research findings were published in the renowned scientific journal Proceedings of the National Academy of Sciences of the United States of America.

Apart from HKBU researchers, the research team also comprised researchers from Shenzhen University, China University of Geosciences, The Chinese University of Hong Kong (Shenzhen), University of Alberta, and Princeton University.

A systematic review and meta-analysis of published studies from three continents published in the journal Anaesthesia (a journal of the Association of Anaesthetists) shows that overall mortality of COVID-19 patients in intensive care units (ICUs) has fallen from almost 60% at the end of March to 42% at the end of May -- a relative decrease of almost one third.

The review also shows ICU mortality for the disease is not significantly different across the three continents included: Europe, Asia and North America. The study is by Professor Tim Cook, Consultant in Anaesthesia and Intensive Care Medicine, Royal United Hospitals Bath NHS Foundation Trust, Bath, UK, and School of Medicine, University of Bristol, UK, and colleagues.

The researchers searched the MEDLINE, EMBASE, PubMed and Cochrane databases up to 31 May 2020 for studies reporting ICU mortality for adult patients admitted with COVID-19. The primary outcome measure was death in ICU as a proportion of completed ICU admissions, either through discharge from the ICU or death. The definition thus did not include patients still alive on ICU.

A total of 24 observational studies including 10,150 patients were identified from centres across Asia, Europe and North America. In patients with completed ICU admissions with COVID-19 infection, combined ICU mortality across all the studies up to the end of May was 41.6%. This represents a fall of around a third from the 59.5% ICU mortality seen in the studies up to the end of March.

The authors say: "The in-ICU mortality from COVID-19, at around 40%, remains almost twice that seen in ICU admissions with other viral pneumonias, at 22%."

There are, say the authors, several explanations for the findings regarding decreasing ICU mortality over time. They say: "It may reflect the rapid learning that has taken place on a global scale due to the prompt publication of clinical reports early in the pandemic. It may also be that ICU admission criteria have changed over time, for example, with greater pressure on ICUs early in the pandemic surge."

They add the findings are also likely to reflect the fact that long ICU stays, for example, due slow weaning from a ventilator, take time to be reflected in the data. Critical illness associated with COVID-19 can last for long periods, with approximately 20% of UK ICU admissions lasting more than 28 days, and 9% more than 42 days.
They say: "The important message, however, is that as the pandemic has progressed and all these factors combine, survival of patients admitted to ICU with COVID-19 has significantly improved."

The ICU mortality did not differ significantly across continents despite some evidence of variations in admission criteria, treatments delivered and the thresholds for their application. The authors say this is consistent with research findings up until the end of May suggesting that no specific therapy reduces ICU mortality. In the last few weeks dexamethasone has been found to have significant benefit and there is hope this will improve survival further.

They conclude: "This systematic review and meta-analysis of ICU outcome in patients with COVID-19 found an in-ICU mortality rate of 41.6% across international studies. There were no significant effects of geographical location, but reported ICU mortality fell over time. Optimistically, as the pandemic progresses, we may be coping better with COVID-19."

Over 70% of young people, some as young as eight, are using apps, YouTube videos and other digital online technologies to track and manage their health, according to the authors of a new report.

The researchers, based at the universities of Bath, Salford and University of New South Wales (Australia) say their findings highlight risks and opportunities for young people and suggest that more needs to be done to expand digital literacy lessons at school to focus on health.

Their recently published report with the Wellcome Trust, Digital Health Generation, describes young people in the UK and around the world as 'growing up in a time when healthcare is increasingly turning towards digital tools'.

From survey data of over 1000 young people, it uncovers that young people are accessing digital health technologies from a very young age - 75% of survey respondents said that they owned their first mobile or tablet between the ages of 8-11 years - with 70% of respondents saying they use these devices for health purposes in relation to fitness or dieting.

According to the report, the growth of these technologies poses problems both in terms of data collection, security and ownership, but also in how young people navigate the multiple and sometimes competing health advice and guidance. As a priority schools should be supported in educating young people about digital health as part of the health curriculum, suggest the researchers.

They point to the significant growth over recent years in a range of websites, blogs, social platforms, apps and wearable technologies accessed and used by young people for health purposes as well as a surge in their use throughout lockdown this year. These cover a diverse range of technologies measuring performance and activity, such as Fitbits and Strava, as well as numerous dieting apps and YouTube videos.

Many of these technologies are focused on promoting 'healthy lifestyles' and can provide young people with important information on their health, including by collecting, tracking and sharing data for instance about how far we run or how much we eat. Yet despite their proliferation, there are currently no guidelines, and young people say they need more support.

Among findings, responses found that while young people often draw on the health advice provided through digital health (e.g. training plans and dietary advice), many were concerned that they would not be able to recognise if they were over-exercising or dieting too much. Digital health tools can also lead some young people to engage with forms of self-monitoring, which have been linked with disordered eating or excessive exercising regimes. In extreme cases, parents or others have intervened to stop young people from using fitness and dieting apps because of their perceived harmful effects.

Lead researcher behind the report, Professor Emma Rich from the Department for Health at the University of Bath explains: "Over recent years there has been a surge of new online apps, blogs and videos specifically targeting young people with messages all about personal improvement in their health and lifestyle. These technologies offer certain opportunities for young people, but they also carry risks both in terms of the direct advice and guidance given - and the implications this can have in relation to body image for instance - but also wider concerns about data storage and ownership by third parties.

"Our findings suggest young people want to learn more about this topic, but need help in navigating a fast-paced, fast-changing online environment. Digital health education should promote learning that will benefit young people in ways that help them feel better prepared to manage their online health identities, particularly in relation to social media. Educational policymakers need to take notice of this specific issue in order to update and expand current provision within the curriculum. This trend in online digital health technologies will only continue to increase and we need to ensure young people have the skills and know-how to best cope."

Co-author, Professor Andy Miah of the University of Salford added: "The research is a world-first, addressing a major and pressing gap in health knowledge by providing unique insights into young people's experiences of digital health technologies promoting 'healthy lifestyles'. The experiences of the young people we spoke to highlighted complexities in digital health: many of the young people who participated in our research and forums have experiences of digital health which are both positive and problematic."

In addressing this issue, the researchers argue that it is essential to bring together different stakeholders, crucially with young people front and centre of policy interventions.

The report was also authored by Dr Sarah Lewis (Bath), Professor Deborah Lupton (New South Wales) and Dr Lukasz Piwek (Bath).

Proponents of campaign finance reform claim that putting limits on how much money can be raised and spent to support a political candidate leads to more competitive elections by helping level the political playing field between incumbents -- the people holding the political office -- and challengers. However, a new study by two social scientists at the University of Missouri finds state campaign finance reforms actually have no beneficial effect on the competitiveness of state legislative elections. Instead, some reforms, such as limits on corporate political spending and public financing of elections, advantage incumbents.

Jeff Milyo, a professor and chair of the Department of Economics in the MU College of Arts and Science, said the study improves on previous studies conducted prior to the ruling in the U.S. Supreme Court case, "Citizens United v. Federal Election Commission." The ruling struck down state laws prohibiting corporations from using their money for political advertising as a violation of the First Amendment's guarantee of freedom of speech.

In the study, researchers examined the competitiveness of state legislative elections before and after various changes in state laws, such as this ruling, Milyo said.

"Our analysis of nearly 66,000 state contests over 30 years -- from 1986 to 2018 -- reveals that most campaign finance reforms have little impact on state legislative elections," Milyo said. "But if anything, the much-maligned Citizens United decision has led to an increase in electoral competitiveness. That decision, which struck down regulations in a number of states, provides a kind of natural experiment to examine the relationship between corporate political spending and the incumbency advantage in state legislative elections."

Milyo said the study also demonstrates that full public financing of legislative elections, or "clean money" reforms that provide a set amount of financing to candidates, may also favor the reelection of an incumbent state legislator. He said it can be difficult for challengers to be successful in winning an election over a longtime state legislator.

"Challengers need to be able to raise and spend money to overcome the many advantages that incumbent legislators enjoy in elections," Milyo said. "That's why campaign finance reforms that limit political spending do not increase competitiveness in elections and sometimes have the opposite effect as might have been intended."

The use of tethered unmanned aerial vehicles (TUAVs) has been modeled as a powerful new tool for improving cellular phone and internet networks. When employed as flying base stations with a cable connection, multirotor drones promise to quickly ramp up coverage, increase the efficiency of urban networks and provide much needed access in remote rural areas.

"Our aim has been to show that TUAVs offer a very appealing solution as a bridge between fixed base stations and free-flying drones," says Mohamed-Slim Alouini, who has authored two papers on the subject with other KAUST mathematicians Mustafa A. Kishk and Ahmed Bader. "We hope our theoretical investigation will spur others to develop the idea to its full potential," says Alouini.

In 2017, after Hurricane Maria devastated Puerto Rico, the U.S. telecommunications company AT&T showed how drones (UAVs) fitted with cellular transceivers could quickly be deployed to replace inoperable base stations and restore mobile coverage. Mathematicians have been calculating the optimal positioning of such "COWs" (cells on wings) ever since.

Adding a cable for power and data has been an obvious development. A U.S. startup called Spooky Action, for example, has been experimenting with TUAVs to connect remote areas of Africa.

TUAVs on the market today can stay aloft for a month or more, much longer than their untethered counterparts, which must land to recharge every hour or so. With a fiber optic line running alongside their power connection, TUAVs can also "backhaul" their data to the core network with much greater efficiency. Their drawback is their restricted mobility, although the cable connecting currently available products can be as long as 150 meters.

Unlike free-flying UAVs, little theoretical work has been done on how best to position their tethered counterparts. The KAUST researchers took two approaches. First, they used exhaustive search optimization; crunching numbers for every item in a set of possible locations, with each location corresponding to a value of coverage probability. Secondly, they derived closed-form expressions for a suboptimal solution; faster arrived at but less accurate. Future modeling will likely use both methods, with the latter greatly reducing the size of the set searched through by the former.

"An interesting result was that with longer tethers, TUAVs will outperform free-flying UAVs in just about every scenario," says Kishk. "Tomorrow's 5G equipment is heavier and consumes more power than 4G today, so their advantage will become more apparent."

Eventually, the three KAUST researchers envisage TUAVs complementing fixed base stations in high-density urban networks.

Tethered to tall buildings, they would offload data during peak hours and shift their position around the clock to cover varying traffic distribution throughout the day.

In the low-density countryside, meanwhile, high-flying TUAVs promise a more viable alternative to expensive, tall towers needed to provide coverage to large but sparsely populated regions.

While the KAUST researchers only looked into the optimal placing of one TUAV for their papers, they are now developing more complex models, featuring two or more flying base stations. They hope that other mathematicians will join them in their pursuit to optimize the use of TUAVs.

Like other highly migratory sharks, tiger sharks (Galeocerdo cuvier) often traverse regional, national and international boundaries where they encounter various environmental and manmade stressors. Their range and habitat use in the Gulf of Mexico, a complex marine environment significantly impacted by the Deepwater Horizon Oil Spill in 2010, has been understudied and remains unknown.

Using sophisticated satellite telemetry, a study is the first to provide unique insights into how tiger sharks move and use habitats in the Gulf of Mexico across life-stages. Data from the study, just published in PLOS ONE, provide an important baseline for comparison against, and/or predicting their vulnerability to future environmental change such as climate variability or oil spills.

For the study, Matt Ajemian, Ph.D., lead author and an assistant research professor at Florida Atlantic University's Harbor Branch Oceanographic Institute, and a team of scientists examined size and sex-related movement and distribution patterns of tiger sharks in the Gulf of Mexico. They fitted 56 tiger sharks with Smart Position and temperature transmitting tags between 2010 - following the Deepwater Horizon Oil Spill - and 2018 - spanning shelf waters from south Texas to south Florida and examined seasonal and spatial distribution patterns across the Gulf of Mexico. The tags transmitted whenever the fin-mounted tags broke the sea surface, with orbiting satellites estimating shark positions based on these transmissions. Ajemian also analyzed overlap of core habitats among individuals relative to large benthic features including oil and gas platforms, natural banks, and bathymetric breaks.

"While all life stages of tiger sharks are known to occur in the Gulf of Mexico, detailed habitat use has never been quantified," said Ajemian. "This is rather striking as this marine system faces numerous manmade stressors, complex tri-national management, and indications of size reductions in recreational landings for large sharks."

Results showed significant ontogenetic and seasonal differences in distribution patterns as well as across-shelf (i.e., regional) and sex-linked variability in movement rates. Prior studies into tiger shark horizontal movements in the western North Atlantic Ocean have been restricted primarily to males or females separately, in disparate locations. By simultaneously tracking many males and females of varying life stages within the same region, the researchers observed sex and size-specific differences in distribution and movement rates, as well as associations with large-scale habitat features. For example, researchers found evidence of tiger shark core regions encompassing the National Oceanographic and Atmospheric Administration designated Habitat Areas of Particular Concern during cooler months, particularly by females. These are specifically bottom features of the Gulf that rise up from the edges of the continental shelf, and include places like the Flower Garden Banks National Marine Sanctuary. Additionally, shark core regions intersected with 2,504 oil and gas platforms, where previous researchers have observed them along the bottom.

The scientists note that future research may benefit from combining alternative tracking tools, such as acoustic telemetry and genetic approaches, which can facilitate long-term assessment of tiger shark movement dynamics and help identify the role of the core habitats identified in this study.

"This research is just a first glimpse into how these iconic predators use the Gulf of Mexico's large marine ecosystem," said Ajemian.

Smartphone accelerometers are effective tools to measure key time-under-tension indicators of muscle training - and could help in resistance-based workouts and rehabilitation protocols.

Article Title: "Using smartphone accelerometer data to obtain scientific mechanical-biological descriptors of resistance exercise training"

Funding: ETH Zurich supplied funding for the hardware used in the current study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Kieser Training AG provided support in the form of salaries for author DA, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of this author is articulated in the 'author contributions' section.

Competing interests: Kieser Training AG provided support in the form of salaries for author DA. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Citation: Viecelli C, Graf D, Aguayo D, Hafen E, Füchslin RM (2020) Using smartphone accelerometer data to obtain scientific mechanical-biological descriptors of resistance exercise training. PLoS ONE 15(7): e0235156. https://doi.org/10.1371/journal.pone.0235156

Article URL: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0235156