It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Wednesday, May 06, 2020
14 mutations found in SARS-CoV-2: One strain may be more easily spread
by Bob Yirka , Medical Xpress
A colorized scanning electron micrograph of the SARS-CoV-2 virus. Credit: NIAID
A team of researchers from Los Alamos National Laboratory, Sheffield Teaching Hospitals NHS and the Duke Human Vaccine Institute and Department of Surgery has found 14 mutations to the SARS-CoV-2 virus, one of which they suspect might be more easily spread. In the interest of speedy dissemination of findings, the group has uploaded their paper to the bioRxiv preprint server rather than waiting for peer review at another journal.
The work involved analyzing the genomes of the virus found in 6,000 infected people from around the globe. They focused most specifically on the virus genes that are responsible for producing the "spike protein," which is the mechanism the virus uses to attach to human cells. In so doing, they found 14 mutations, but one they named D614G (also known as G614) stood out because it was found in almost all samples outside of China. It was also particularly notable because it appeared to replace a prior mutation called D614. They also noted that in the original outbreak in China, there were only D614 mutations. It was only after the virus began appearing in Europe that the G614 mutation emerged. They suggest that the fact that the G614 virus took over from the prior mutation could mean it is more easily spread. Notably, after the mutation appeared in Europe, the G614 mutation began appearing in samples from other sites around the world, suggesting that this new strain is behind the global pandemic.
Others in the medical science field have expressed skepticism about the suggestions made by the team, insisting that it is far too soon to assume that any of the various strains of the virus are any more contagious than the original strain in China. Some have even suggested that the reason the strain with the G614 mutation has spread so far and wide is because it happened to infect regions that did not begin mitigation efforts in the earliest days of the pandemic. In either case, more work is required to ascertain whether any strains are more contagious than any other, and also to determine if the virus mutates at a rate that could outpace vaccine development.
More information: Bette Korber et al. Spike mutation pipeline reveals the emergence of a more transmissible form of SARS-CoV-2, bioRxiv (2020). DOI: 10.1101/2020.04.29.069054
Climate change could reawaken Indian Ocean El Nino
Evidence of an ice age Indian Ocean El Niño was found in the chemistry of these 21,000 year old foram shells by Thirumalai in 2017, when he was a postdoctoral fellow at the University of Texas Institute for Geophysics. The researchers now think the processes driving Indian Ocean El Niño during global cooling were very similar to those under global warming. Credit: Kaustubh Thirumalai
Global warming is approaching a tipping point that during this century could reawaken an ancient climate pattern similar to El Niño in the Indian Ocean, new research led by scientists from The University of Texas at Austin has found.
If it comes to pass, floods, storms and drought are likely to worsen and become more regular, disproportionately affecting populations most vulnerable to climate change.
Computer simulations of climate change during the second half of the century show that global warming could disturb the Indian Ocean's surface temperatures, causing them to rise and fall year to year much more steeply than they do today. The seesaw pattern is strikingly similar to El Niño, a climate phenomenon that occurs in the Pacific Ocean and affects weather globally.
"Our research shows that raising or lowering the average global temperature just a few degrees triggers the Indian Ocean to operate exactly the same as the other tropical oceans, with less uniform surface temperatures across the equator, more variable climate, and with its own El Niño," said lead author Pedro DiNezio, a climate scientist at the University of Texas Institute for Geophysics, a research unit of the UT Jackson School of Geosciences.
According to the research, if current warming trends continue, an Indian Ocean El Niño could emerge as early as 2050.
The results, which were published May 6 in the journal Science Advances, build on a 2019 paper by many of the same authors who found evidence of a past Indian Ocean El Niño hidden in the shells of microscopic sea life, called forams, that lived 21,000 years ago—the peak of the last ice age when the Earth was much cooler.
To show whether an Indian Ocean El Niño can occur in a warming world, the scientists analyzed climate simulations, grouping them according to how well they matched present-day observations. When global warming trends were included, the most accurate simulations were those showing an Indian Ocean El Niño emerging by 2100.
Rainfall simulations in the Indian Ocean under future global warming show more extreme periods of deluge and drought. According to the University of Texas-led study, the climate swings are the result of Indian Ocean El Niño and La Niña that could emerge within the 21st century if today's greenhouse warming trends continue. Credit: Pedro DiNezio
"Greenhouse warming is creating a planet that will be completely different from what we know today, or what we have known in the 20th century," DiNezio said.
The latest findings add to a growing body of evidence that the Indian Ocean has potential to drive much stronger climate swings than it does today.
Co-author Kaustubh Thirumalai, who led the study that discovered evidence of the ice age Indian Ocean El Niño, said that the way glacial conditions affected wind and ocean currents in the Indian Ocean in the past is similar to the way global warming affects them in the simulations.
"This means the present-day Indian Ocean might in fact be unusual," said Thirumalai, who is an assistant professor at the University of Arizona.
The Indian Ocean today experiences very slight year-to-year climate swings because the prevailing winds blow gently from west to east, keeping ocean conditions stable. According to the simulations, global warming could reverse the direction of these winds, destabilizing the ocean and tipping the climate into swings of warming and cooling akin to the El Niño and La Niña climate phenomena in the Pacific Ocean. The result is new climate extremes across the region, including disruption of the monsoons over East Africa and Asia.
Thirumalai said that a break in the monsoons would be a significant concern for populations dependent on the regular annual rains to grow their food.
For Michael McPhaden, a physical oceanographer at the National Oceanic and Atmospheric Administration who pioneered research into tropical climate variability, the paper highlights the potential for how human-driven climate change can unevenly affect vulnerable populations.
"If greenhouse gas emissions continue on their current trends, by the end of the century, extreme climate events will hit countries surrounding the Indian Ocean, such as Indonesia, Australia and East Africa with increasing intensity," said McPhaden, who was not involved in the study. "Many developing countries in this region are at heightened risk to these kinds of extreme events even in the modern climate."Indian Ocean phenomenon spells climate trouble for Australia
A study in the May 6th issue of Nature indicates the increase in rainfall forecast by global climate models is likely to hasten the release of carbon dioxide from tropical soils, further intensifying global warming by adding to human emissions of this greenhouse gas into Earth's atmosphere.
Based on analysis of sediments cored from the submarine delta of the Ganges and Brahmaputra rivers, the study was conducted by an international team led by Dr. Christopher Hein of William & Mary's Virginia Institute of Marine Science. Collaborators include Drs. Valier Galy of the Woods Hole Oceanographic Institution, Muhammed Usman of the University of Toronto, and Timothy Eglinton and Negar Haghipour of the Swiss Federal Institute of Technology in Zurich (ETH Zurich). Major funding was provided by the U.S. National Science Foundation.
"We found that shifts toward a warmer and wetter climate in the drainage basin of the Ganges and Brahmaputra rivers over the last 18,000 years enhanced rates of soil respiration and decreased stocks of soil carbon," says Hein. "This has direct implications for Earth's future, as climate change is likely to increase rainfall in tropical regions, further accelerating respiration of soil carbon, and adding even more CO2 to the atmosphere than that directly added by humans."
Soil respiration refers to release of carbon dioxide by microbes as they decompose and metabolize leaf litter and other organic materials on and just below the ground surface. It's equivalent to the process in which larger multicellular animals—from snails to humans—exhale CO2 as a byproduct of metabolizing their food. Roots also contribute to soil respiration at night, when photosynthesis shuts down and plants burn some of the carbohydrates they produced during daylight.
Sediment cores reveal link between precipitation, soil age
The team's study is based on detailed analysis of three sediment cores collected from the ocean floor seaward of the mouth of the Ganges and Brahmaputra rivers in Bangladesh. Here, the world's largest delta and submarine fan were built by the prodigious volume of sediments eroded from the Himalayas. The two rivers carry more than a billion tons of sediment to the Bay of Bengal each year, more than five times that of the Mississippi River.
The cores record the environmental history of the Ganges-Brahmaputra drainage basin during the 18,000 years since the last Ice Age began to wane. By comparing radiocarbon dates of bulk sediment samples from these cores with samples from organic molecules known to be derived directly from land plants, the researchers were able to gauge changes though time in the age of the sediments' parent soils.
Their results showed a strong correlation between runoff rates and soil age—wetter epochs were associated with younger, rapidly respiring soils; while drier, cooler epochs were linked to older soils capable of storing carbon for longer periods.
The wetter periods themselves correlate with the strength of the Indian summer monsoon, the primary source of precipitation across India, the Himalayas, and south-central Asia. The researchers confirmed changes in monsoon strength using several independent lines of paleoclimatic evidence, including analysis of oxygen-isotope ratios from Chinese cave deposits and the skeletons of open-ocean phytoplankton.
Small changes, big effects
The magnitude of the correlation discovered by Hein and colleagues corresponds to a near doubling in the rate of soil respiration and carbon turnover in the 2,600 years following the end of the last Ice Age, as India's summer monsoon strengthened. "We found that a small increase in precipitation values corresponds to a much larger decrease in soil age," says Hein.
An earlier paper by Hein, Galy, and colleagues reported a threefold increase in annual rainfall in the Ganges-Brahmaputra river basin since the last Ice Age. This new study shows that upturn in precipitation led to a halving of soil age due to more rapid soil turnover.
Hein says "small changes in the amount of carbon stored in soils can moreover play an outsized role in modulating atmospheric CO2 concentrations and, therefore, global climate, as soils are a primary global reservoir of this element."
The current concentration of carbon dioxide in Earth's atmosphere—416 parts per million—equates to about 750 billion tons of carbon. Earth's soils hold around 3,500 billion tons—more than four times as much.
Previous research has highlighted the threat that global warming poses to the permafrost soils of the Arctic, whose widespread thawing is thought to be releasing up to 0.6 billion tons of carbon to the atmosphere each year.
"We've now found a similar climate feedback in the tropics," says Hein, "and are concerned that enhanced soil respiration due to greater precipitation—itself a response to climate change—will further increase concentrations of CO2 in our atmosphere."Forest soils release more carbon dioxide than expected in rainy season
This graphic illustrates the vapor buoyancy effect, in which cold, humid air rises because it is lighter than dry air. Credit: Da Yang/UC Davis
Conventional knowledge has it that warm air rises while cold air sinks. But a study from the University of California, Davis, found that in the tropical atmosphere, cold air rises due to an overlooked effect—the lightness of water vapor. This effect helps to stabilize tropical climates and buffer some of the impacts of a warming climate.
The study, published today in the journal Science Advances, is among the first to show the profound implications water vapor buoyancy has on Earth's climate and energy balance.
"It's well-known that water vapor is an important greenhouse gas that warms the planet," said senior author Da Yang, an assistant professor of atmospheric sciences at UC Davis and a joint faculty scientist with Lawrence Berkeley National Laboratory. "But on the other hand, water vapor has a buoyancy effect which helps release the heat of the atmosphere to space and reduce the degree of warming. Without this lightness of water vapor, the climate warming would be even worse."
Humid air is lighter than dry air under the same temperature and pressure conditions. This is called the vapor buoyancy effect. This study discovered this effect allows cold, humid air to rise, forming clouds and thunderstorms in Earth's tropics. Meanwhile, warm, dry air sinks in clear skies. Earth's atmosphere then emits more energy to space than it otherwise would without vapor buoyancy.
The study found that the lightness of water vapor increases Earth's thermal emission by about 1-3 watts per square meter over the tropics. That value compares with the amount of energy captured by doubling carbon dioxide in the atmosphere. The authors' calculations further suggest that the radiative effects of vapor buoyancy increase exponentially with climate warming.
A better understanding of the vapor buoyancy effect and its stabilizing role in the tropics can also improve cloud and thunderstorm simulations, as well as climate models, the study said.
"Now that we understand how the lightness of water regulates tropical climate, we plan to study whether global climate models accurately represent this effect," said the study's lead author, Seth Seidel, a graduate student researcher at UC Davis. Measuring the effect of water vapor on climate warming More information: "The lightness of water vapor helps to stabilize tropical climate" Science Advances (2020). Journal information: Science Advances
Police stop fewer black drivers at night when a 'veil of darkness' obscures their race
The Stanford-led study also found that when drivers were pulled over, officers searched the cars of blacks and Hispanics more often than whites
STANFORD SCHOOL OF ENGINEERING
The largest-ever study of alleged racial profiling during traffic stops has found that blacks, who are pulled over more frequently than whites by day, are much less likely to be stopped after sunset, when "a veil of darkness" masks their race.
That is one of several examples of systematic bias that emerged from a five-year study that analyzed 95 million traffic stop records, filed by officers with 21 state patrol agencies and 35 municipal police forces from 2011 to 2018.
The Stanford-led study also found that when drivers were pulled over, officers searched the cars of blacks and Hispanics more often than whites. The researchers also examined a subset of data from Washington and Colorado, two states that legalized marijuana, and found that while this change resulted in fewer searches overall, and thus fewer searches of blacks and Hispanics, minorities were still more likely than whites to have their cars searched after a pull-over.
"Our results indicate that police stops and search decisions suffer from persistent racial bias, and point to the value of policy interventions to mitigate these disparities," the researchers write in the May 4th issue of Nature Human Behaviour.
The paper culminates a five-year collaboration between Stanford's Cheryl Phillips, a journalism lecturer whose graduate students obtained the raw data through public records requests, and Sharad Goel, a professor of management science and engineering whose computer science team organized and analyzed the data.
Goel and his collaborators, which included Ravi Shroff, a professor of applied statistics at New York University, spent years culling through the data, eliminating records that were incomplete or from the wrong time periods, to create the 95 million-record database that was the basis for their analysis. "There is no way to overstate the difficulty of that task," Goel said.
Creating that database enabled the team to find the statistical evidence that a "veil of darkness" partially immunized blacks against traffic stops. That term and idea has been around since 2006 when it was used in a study that compared the race of 8,000 drivers in Oakland, California, who were stopped at any time of day or night over a six month period. But the findings from that study were inconclusive because the sample was too small to prove a link between the darkness of the sky and the race of the stopped drivers.
The Stanford team decided to repeat the analysis using the much larger dataset that they had gathered. First, they narrowed the range of variables they had to analyze by choosing a specific time of day - around 7 p.m. - when the probable causes for a stop were more or less constant. Next, they took advantage of the fact that, in the months before and after daylight saving time each year, the sky gets a little darker or lighter, day by day. Because they had such a massive database, the researchers were able to find 113,000 traffic stops, from all of the locations in their database, that occurred on those days, before or after clocks sprang forward or fell back, when the sky was growing darker or lighter at around 7 p.m. local time.
This dataset provided a statistically valid sample with two important variables - the race of the driver being stopped, and the darkness of the sky at around 7 p.m. The analysis left no doubt that the darker it got, the less likely it became that a black driver would be stopped. The reverse was true when the sky was lighter.
More than any single finding, the collaboration's most lasting impact may be from the Stanford Open Policing Project, which the researchers started to make their data available to investigative and data-savvy reporters, and to hold workshops to help reporters learn how to use the data to do local stories.
For example, the researchers helped reporters at the Seattle-based non-profit news organization, Investigate West, understand the patterns in the data for stories showing bias in police searches of Native Americans. That reporting prompted the Washington State Patrol to review its practices and boost officer training. Similarly, the researchers helped reporters at the Los Angeles Times analyze data that showed how police searched minority drivers far more often than whites. It resulted in a story that was part of a larger investigative series that prompted changes in Los Angeles Police Department practices.
"All told we've trained about 200 journalists, which is one of the unique things about this project," Phillips said.
Goel and Phillips plan to continue collaborating through a project called Big Local News that will explore how data science can shed light on public issues, such as civil asset forfeitures - instances in which law enforcement is authorized to seize and sell property associated with a crime. Gathering and analyzing records of when and where such seizures occur, to whom, and how such property is disposed will help shed light on how this practice is being used. Big Local News is also working on collaborative efforts to standardize information from police disciplinary cases.
"These projects demonstrate the power of combining data science with journalism to tell important stories," Goel said.
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Study finds stronger links between automation and inequality Job-replacing tech has directly driven the income gap since the late 1980s, economists report.
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
This is part 3 of a three-part series examining the effects of robots and automation on employment, based on new research from economist and Institute Professor Daron Acemoglu.
CAMBRIDGE, Mass. -- Modern technology affects different workers in different ways. In some white-collar jobs -- designer, engineer -- people become more productive with sophisticated software at their side. In other cases, forms of automation, from robots to phone-answering systems, have simply replaced factory workers, receptionists, and many other kinds of employees.
Now a new study co-authored by an MIT economist suggests automation has a bigger impact on the labor market and income inequality than previous research would indicate -- and identifies the year 1987 as a key inflection point in this process, the moment when jobs lost to automation stopped being replaced by an equal number of similar workplace opportunities.
"Automation is critical for understanding inequality dynamics," says MIT economist Daron Acemoglu, co-author of a newly published paper detailing the findings.
Within industries adopting automation, the study shows, the average "displacement" (or job loss) from 1947-1987 was 17 percent of jobs, while the average "reinstatement" (new opportunities) was 19 percent. But from 1987-2016, displacement was 16 percent, while reinstatement was just 10 percent. In short, those factory positions or phone-answering jobs are not coming back.
"A lot of the new job opportunities that technology brought from the 1960s to the 1980s benefitted low-skill workers," Acemoglu adds. "But from the 1980s, and especially in the 1990s and 2000s, there's a double whammy for low-skill workers: They're hurt by displacement, and the new tasks that are coming, are coming slower and benefitting high-skill workers." The new paper, "Unpacking Skill Bias: Automation and New Tasks," will appear in the May issue of the American Economic Association: Papers and Proceedings. The authors are Acemoglu, who is an Institute Professor at MIT, and Pascual Restrepo PhD '16, an assistant professor of economics at Boston University.
Low-skill workers: Moving backward The new paper is one of several studies Acemoglu and Restrepo have conducted recently examining the effects of robots and automation in the workplace. In a just-published paper, they concluded that across the U.S. from 1993 to 2007, each new robot replaced 3.3 jobs.
In still another new paper, Acemoglu and Restrepo examined French industry from 2010 to 2015. They found that firms that quickly adopted robots became more productive and hired more workers, while their competitors fell behind and shed workers -- with jobs again being reduced overall.
In the current study, Acemoglu and Restrepo construct a model of technology's effects on the labor market, while testing the model's strength by using empirical data from 44 relevant industries. (The study uses U.S. Census statistics on employment and wages, as well as economic data from the Bureau of Economic Analysis and the Bureau of Labor Studies, among other sources.)
The result is an alternative to the standard economic modeling in the field, which has emphasized the idea of "skill-biased" technological change -- meaning that technology tends to benefit select high-skilled workers more than low-skill workers, helping the wages of high-skilled workers more, while the value of other workers stagnates. Think again of highly trained engineers who use new software to finish more projects more quickly: They become more productive and valuable, while workers lacking synergy with new technology are comparatively less valued. However, Acemoglu and Restrepo think even this scenario, with the prosperity gap it implies, is still too benign. Where automation occurs, lower-skill workers are not just failing to make gains; they are actively pushed backward financially. Moreover, Acemoglu and Restrepo note, the standard model of skill-biased change does not fully account for this dynamic; it estimates that productivity gains and real (inflation-adjusted) wages of workers should be higher than they actually are.
More specifically, the standard model implies an estimate of about 2 percent annual growth in productivity since 1963, whereas annual productivity gains have been about 1.2 percent; it also estimates wage growth for low-skill workers of about 1 percent per year, whereas real wages for low-skill workers have actually dropped since the 1970s. "Productivity growth has been lackluster, and real wages have fallen," Acemoglu says. "Automation accounts for both of those." Moreover, he adds, "Demand for skills has gone down almost exclusely in industries that have seen a lot of automation." Why "so-so technologies" are so, so bad
Indeed, Acemoglu says, automation is a special case within the larger set of technological changes in the workplace. As he puts it, automation "is different than garden-variety skill-biased technological change," because it can replace jobs without adding much productivity to the economy.
Think of a self-checkout system in your supermarket or pharmacy: It reduces labor costs without making the task more efficient. The difference is the work is done by you, not paid employees. These kinds of systems are what Acemoglu and Restrepo have termed "so-so technologies," because of the minimal value they offer.
"So-so technologies are not really doing a fantastic job, nobody's enthusiastic about going one-by-one through their items at checkout, and nobody likes it when the airline they're calling puts them through automated menus," Acemoglu says. "So-so technologies are cost-saving devices for firms that just reduce their costs a little bit but don't increase productivity by much. They create the usual displacement effect but don't benefit other workers that much, and firms have no reason to hire more workers or pay other workers more."
To be sure, not all automation resembles self-checkout systems, which were not around in 1987. Automation at that time consisted more of printed office records being converted into databases, or machinery being added to sectors like textiles and furniture-making. Robots became more commonly added to heavy industrial manufacturing in the 1990s. Automation is a suite of technologies, continuing today with software and AI, which are inherently worker-displacing. "Displacement is really the center of our theory," Acemoglu says. "And it has grimmer implications, because wage inequality is associated with disruptive changes for workers. It's a much more Luddite explanation."
After all, the Luddites -- British textile mill workers who destroyed machinery in the 1810s -- may be synonymous with technophobia, but their actions were motivated by economic concerns; they knew machines were replacing their jobs. That same displacement continues today, although, Acemoglu contends, the net negative consequences of technology on jobs is not inevitable. We could, perhaps, find more ways to produce job-enhancing technologies, rather than job-replacing innovations.
"It's not all doom and gloom," says Acemoglu. "There is nothing that says technology is all bad for workers. It is the choice we make about the direction to develop technology that is critical."
New research finds racial bias in rideshare platforms
Minority riders are twice as likely to have rides canceled than caucasians INSTITUTE FOR OPERATIONS RESEARCH AND THE MANAGEMENT SCIENCES
INFORMS Journal Management Science New Study Key Takeaways:
Under-represented minorities are more than twice as likely to have a ride canceled compared to Caucasians.
The racial bias is lessened during peak demand times.
Rides are more likely to be canceled for people who show support for the LGBT community with no changes during peak demand times.
CATONSVILLE, MD, May 6, 2020 - New research to be published in the INFORMS journal Management Science has found popular rideshare platforms exhibit racial and other biases that penalize under-represented minorities and others seeking to use their services.
The study, "When Transparency Fails: Bias and Financial Incentives in Ridesharing Platforms," was conducted by Jorge Mejia of Indiana University and Chris Parker of American University. In addition to finding racial biases persist, similar phenomena were also documented against people who show support for the LGBT community.
Data was analyzed from a major rideshare platform in Washington, D.C., between early October to mid-November 2018. The experiment manipulated rider names and profile pictures to observe drivers' behavior patterns in accepting and canceling rides. To illustrate support for LGBT rights a rainbow profile picture filter was used. In addition, times of ride requests varied to determine how peak and non-peak price periods impact bias.
"We found under-represented minorities are more than twice as likely to have a ride canceled than Caucasians, that's about 3% versus 8%," said Mejia, an assistant professor in the Kelley School of Business at Indiana. "Along with racial bias, LGBT biases are persistent, while there is no evidence of gender bias."
Peak timing was found to have a moderating effect, with lower cancelation rates for minority riders, but the timing doesn't appear to change the bias for riders that signal support for the LGBT community.
"Data-driven solutions may exist wherein rider characteristics are captured when a driver cancels, and the platform penalizes the driver for the biased behavior. One possible way to punish drivers is to move them down the priority list when they exhibit biased cancelation behavior, so they have fewer ride requests. Alternatively, less-punitive measures may provide 'badges' for drivers that exhibit especially low cancelation rates for minority riders," concluded Mejia.
About INFORMS and Management Science
Management Science is a premier peer-reviewed scholarly journal focused on research using quantitative approaches to study all aspects of management in companies and organizations. It is published by INFORMS, the leading international association for operations research and analytics professionals. More information is available at http://www.informs.org or @informs.
Study reveals most critically ill patients with COVID-19 survive with standard treatment
MASSACHUSETTS GENERAL HOSPITAL
Clinicians from two hospitals in Boston report that the majority of even the sickest patients with COVID-19--those who require ventilators in intensive care units--get better when they receive existing guideline-supported treatment for respiratory failure. The clinicians, who are from Massachusetts General Hospital (MGH) and Beth Israel Deaconess Medical Center, published their findings in theAmerican Journal of Respiratory and Critical Care Medicine.
During the COVID-19 pandemic, hospitals around the world have shared anecdotal experiences to help inform the care of affected patients, but such anecdotes do not always reveal the best treatment strategies, and they can even lead to harm. To provide more reliable information, a team led by C. Corey Hardin, MD, PhD, an Assistant Professor of Medicine at MGH and Harvard Medical School, carefully examined the records of 66 critically ill patients with COVID-19 who experienced respiratory failure and were put on ventilators, making note of their responses to the care they received.
The investigators found that the most severe cases of COVID-19 result in a syndrome called Acute Respiratory Distress Syndrome (ARDS), a life-threatening lung condition that can be caused by a wide range of pathogens. "The good news is we have been studying ARDS for over 50 years and we have a number of effective evidenced-based therapies with which to treat it," said Dr. Hardin. "We applied these treatments--such as prone ventilation where patients are turned onto their stomachs--to patients in our study and they responded to them as we would expect patients with ARDS to respond."
Importantly, the death rate among critically ill patients with COVID-19 treated this way--16.7%--was not nearly as high as has been reported by other hospitals. Also, over a median follow-up of 34 days, 75.8% of patients who were on ventilators were discharged from the intensive care unit. "Based on this, we recommend that clinicians provide evidence-based ARDS treatments to patients with respiratory failure due to COVID-19 and await standardized clinical trials before contemplating novel therapies," said co-lead author Jehan Alladina, MD, an Instructor in Medicine at Mass General.
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Paper cited: Ziehr DR, Alladina J, Petri CR, et al. Respiratory Pathophysiology of Mechanically Ventilated Patients with COVID-19: A Cohort Study [published online ahead of print, 2020 Apr 29]. Am J Respir Crit Care Med. 2020;10.1164/rccm.202004-1163LE. doi:10.1164/rccm.202004-1163LE
About Massachusetts General Hospital
Massachusetts General Hospital, founded in 1811, is the original and largest teaching hospital of Harvard Medical School. The Mass General Research Institute conducts the largest hospital-based research program in the nation, with annual research operations of more than $1 billion and comprises more than 9,500 researchers working across more than 30 institutes, centers and departments. In August 2019, Mass General was named #2 in the U.S. News & World Report list of "America's Best Hospitals."
Disclaimer: AAAS and EurekAlert! are not responsible for the
During tough times, ancient 'tourists' sought solace in Florida oyster feasts
FLORIDA MUSEUM OF NATURAL HISTORY
IMAGE: OUT-OF-TOWNERS FLOCKED TO CEREMONIAL SITES ON FLORIDA'S GULF COAST FOR HUNDREDS OF YEARS TO SOCIALIZE AND FEAST. CRYSTAL RIVER WAS HOME TO ONE OF THE MOST PROMINENT SITES, WHICH FEATURED... view more
CREDIT: THOMAS J. PLUCKHAHN
GAINESVILLE, Fla. --- More than a thousand years ago, people from across the Southeast regularly traveled to a small island on Florida's Gulf Coast to bond over oysters, likely as a means of coping with climate change and social upheaval.
Archaeologists' analysis of present-day Roberts Island, about 50 miles north of Tampa Bay, showed that ancient people continued their centuries-long tradition of meeting to socialize and feast, even after an unknown crisis around A.D. 650 triggered the abandonment of most other such ceremonial sites in the region. For the next 400 years, out-of-towners made trips to the island, where shell mounds and a stepped pyramid were maintained by a small group of locals. But unlike the lavish spreads of the past, the menu primarily consisted of oysters, possibly a reflection of lower sea levels and cool, dry conditions.
People's persistence in gathering at Roberts Island, despite regional hardship, underscores their commitment to community, said study lead author C. Trevor Duke, a researcher in the Florida Museum of Natural History's Ceramic Technology Lab.
"What I found most compelling was the fact that people were so interested in keeping their ties to that landscape in the midst of all this potential climate change and abandonment," said Duke, a Ph.D. candidate in the University of Florida department of anthropology. "They still put forth the effort to harvest all these oysters and keep these social relationships active. These gatherings probably occurred when different groups of people were getting together and trying to figure out the future."
Duke and his collaborators compared animal remains from shell mounds and middens - essentially kitchen trash heaps - at Roberts Island and Crystal River, home to an older, more prominent ceremonial site. Their findings showed Crystal River residents "pulled out all the stops" for ritual feasts, regaling visitors with deer, alligator, sharks and dozens of other dishes, while at Roberts Island, feasts consisted of "oysters and very little else," Duke said.
The Roberts Island ceremonial site, which was vacated around A.D. 1050, was one of the last outposts in what was once a flourishing network of religious sites across the Eastern U.S. These sites were characterized by burial grounds with distinctly decorated ceramics known as Swift Creek and Weeden Island pottery. What differentiated Roberts Island and Crystal River from other sites was that their continuous occupation by a small group of residents who prepared for the influx of hundreds of visitors - not unlike Florida's tourist towns today.
"These were very cosmopolitan communities," Duke said. "I'm from Broward County, but I also spent time in the Panhandle, so I'm used to being part of a small residential community that deals with a massive population boom for a month or two months a year. That has been a Florida phenomenon for at least two thousand years."
Archaeologists estimate small-scale ceremonies began at Crystal River around A.D. 50, growing substantially after a residential community settled the site around A.D. 200. Excavations have uncovered minerals and artifacts from the Midwest, including copper breastplates from the Great Lakes. Similarly, conch shells from the Gulf Coast have been found at Midwestern archaeological sites.
"There was this long-distance reciprocal exchange network going on across much of the Eastern U.S. that Crystal River was very much a part of," Duke said.
Religious ceremonies at Crystal River included ritual burials and marriage alliances, Duke said, solidifying social ties between different groups of people. But the community was not immune to the environmental and social crises that swept the region, and the site was abandoned around A.D. 650. A smaller ceremonial site was soon established less than a mile downstream on Roberts Island, likely by a remnant of the Crystal River population.
Duke and his collaborators collected samples from mounds and middens at the two ceremonial sites, identifying the species present and calculating the weight of the meat they would have contained. They found that feasts at hard-strapped Roberts Island featured far fewer species. Meat from oysters and other bivalves accounted for 75% of the weight of Robert Island samples and roughly 25% of the weight from Crystal River. Meat from deer and other mammals made up 45% of the weight in Crystal River samples and less then 3% from Roberts Island.
Duke said evidence suggests that Roberts Island residents also had to travel farther to harvest food. As sea levels fell, oyster beds may have shifted seaward, possibly explaining why the Crystal River population relocated to the island, which was small and had few resources.
"Previous research suggests that environmental change completely rearranged the distribution of reefs and the ecosystem," Duke said. "They had to go far out to harvest these things to keep their ritual program active."
No one knows what caused the widespread abandonment of most of the region's ceremonial sites in A.D. 650, Duke said. But the production of Weeden Island pottery, likely associated with religious activities, ramped up as bustling sites became ghost towns.
"That's kind of counterintuitive," he said. "This religious movement comes on really strong right as this abandonment is happening. It almost seems like people were trying to do something, create some kind of intervention to stop whatever was happening."
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Thomas Pluckhahn of the University of South Florida and J. Matthew Compton of Georgia Southern University also co-authored the study.
Infectious disease modeling study casts doubt on impact of Justinianic plague
Work shows value of new examinations of old narratives of this pandemic
UNIVERSITY OF MARYLAND
ANNAPOLIS, Md. - Many have claimed the Justinianic Plague (c. 541-750 CE) killed half of the population of Roman Empire. Now, historical research and mathematical modeling challenge the death rate and severity of this first plague pandemic.
Researchers Lauren White, PhD and Lee Mordechai, PhD, of the University of Maryland's National Socio-Environmental Synthesis Center (SESYNC), examined the impacts of the Justinianic Plague with mathematical modeling. Using modern plague research as their basis, the two developed novel mathematical models to re-examine primary sources from the time of the Justinianic Plague outbreak. From the modeling, they found that it was unlikely that any transmission route of the plague would have had both the mortality rate and duration described in the primary sources. Their findings appear in a paper titled "Modeling the Justinianic Plague: Comparing hypothesized transmission routes" in PLOS ONE.
"This is the first time, to our knowledge, that a robust mathematical modeling approach has been used to investigate the Justinianic Plague," said lead author Lauren White, PhD, a quantitative disease ecologist and postdoctoral fellow at SESYNC. "Given that there is very little quantitative information in the primary sources for the Justinianic Plague, this was an exciting opportunity to think creatively about how we could combine present-day knowledge of plague's etiology with descriptions from the historical texts."
White and Mordechai focused their efforts on the city of Constantinople, capital of the Roman Empire, which had a comparatively well-described outbreak in 542 CE. Some primary sources claim plague killed up to 300,000 people in the city, which had a population of some 500,000 people at the time. Other sources suggest the plague killed half the empire's population. Until recently, many scholars accepted this image of mass death. By comparing bubonic, pneumonic, and combined transmission routes, the authors showed that no single transmission route precisely mimicked the outbreak dynamics described in these primary sources.
Existing literature often assumes that the Justinianic Plague affected all areas of the Mediterranean in the same way. The new findings from this paper suggest that given the variation in ecological and social patterns across the region (e.g., climate, population density), it is unlikely that a plague outbreak would have impacted all corners of the diverse empire equally.
"Our results strongly suggest that the effects of the Justinianic Plague varied considerably between different urban areas in late antiquity," said co-author Lee Mordechai, an environmental historian and a postdoctoral fellow at SESYNC when he wrote the paper. He is now a senior lecturer at the Hebrew University of Jerusalem, and co-lead of Princeton's Climate Change and History Research Initiative (CCHRI). He said, "This paper is part of a series of publications in recent years that casts doubt on the traditional interpretation of plague using new methodologies. It's an exciting time to do this kind of interdisciplinary research!"
Using an approach called global sensitivity analysis, White and Mordechai were able to explore the importance of any given model parameter in dictating simulated disease outcomes. They found that several understudied parameters are also very important in determining model results. White explained, "One example was the transmission rate from fleas to humans. Although the analysis described this as an important parameter, there hasn't been enough research to validate a plausible range for that parameter."
These high importance variables with minimal information also point to future directions for empirical data collection. "Working with mathematical models of disease was an insightful process for me as a historian," reflected Mordechai. "It allowed us to examine traditional historical arguments with a powerful new lens."
Together, with other recent work from Mordechai, this study is another call to examine the primary sources and narratives surrounding the Justinianic Plague more critically.
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White, L.A. & Mordechai, L. (2020). Modeling the Justinianic Plague: Comparing hypothesized transmission routes. PLOS ONE. doi: 10.1371/journal.pone.0231256
About SESYNC: The University of Maryland's National Socio-Environmental Synthesis Center (SESYNC) in Annapolis brings together the science of the natural world with the science of human behavior and decision making to find solutions to complex environmental problems. SESYNC is funded by an award to the University of Maryland from the National Science Foundation. For more information on SESYNC and its activities, please visit http://www.sesync.org.
