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)
Monday, October 19, 2020
Scientists improve model of landslide-induced tsunami
MIPT researchers Leopold Lobkovsky and Raissa Mazova, and their young colleagues from Nizhny Novgorod State Technical University have created a model of landslide-induced tsunamis that accounts for the initial location of the landslide body. Reported in Landslides, the model reveals that tsunami height is affected by the coastal slope and the position of the land mass before slipping. The highest and most devastating waves result from onshore landslide masses. This realization will make future predictions of tsunamis more accurate, as well as providing deeper insights into past events.
The recent decades have seen unusually large tsunamis that had on-shelf sources and were not always accompanied by seismic events. Instead, the underlying cause may be a fully or partially underwater landslide.
Researchers come up with models to predict wave runup onto the shore following a landslide on an underwater slope. The challenging part is to account for the nonlinear nature of wave runup and rundown, as well as the complex shelf zone geometry. Another important factor at the heart of the models is the technique used to compute landslide mass movement.
A number of landslide-induced tsunami models have been developed, with two of them used the most. The so-called rigid-block models assume a solid state perspective on the motion of the landslide, with shallow-water equations governing the generation of surface water waves. Models of the other type -- referred to as viscoplastic -- rely on shallow-water equations to describe both surface wave generation and landslide movement.
Despite a number of refinements accounting for some features of landslide mass movement, the models have so far remained hydrodynamic in their nature. This means they are not helpful for analyzing the detailed structure of the landslide body or the characteristics of its constituents during the slip. But unless the actual physical properties of the landslide mass are considered, modeling its movement is problematic.
The study reported in this story employs an elastoplastic model presented in 2000 by Igor Garagash and Leopold Lobkovsky. It accounts for the detailed structure of the landslide body and the mechanical characteristics of the land mass constituents during the slip, as well as incorporating the processes occurring in the landslide body. The model implementation in the study relied on the programming code called FLAC 3D, which enables calculations under an explicit finite-difference scheme for solving three-dimensional problems of continuum mechanics.
The researchers found that wave runup onto the shore varied considerably depending on the initial position of the landslide body on the shelf slope, even when the other parameters were fixed.
"In contrast to other models, where the tsunami wave climbs the original coastal slope, here the slope surface is continuously transformed during the landslide motion," study co-author Raissa Mazova from MIPT explained. "In other words, at each moment of time, the tsunami runup occurs onto a new surface of the coastal slope, which leads to a complex displacement of the shoreline. Such an effect has not been obtained before, and it is impossible to obtain within the framework of the movement of a landslide as a solid body or within the framework of a viscous model."
The role of the sediment layer on the slope also proved substantial. The numerical simulation predicts maximum runup on the slope for tsunamis induced by landslide masses initially located on a dry shore.
"Rather than attempting to implement a novel methodology for calculating a landslide model, we used a familiar model, introducing additional boundary conditions," commented Leopold Lobkovsky, a member of the Russian Academy of Sciences and the head of the MIPT Laboratory of Geophysical Research of the Arctic and Continental Margins of the World Ocean. "Our findings demonstrate that shoreline dynamics significantly depend on the initial location of the landslide body, with the shoreline point potentially shifting. This feature may enable us to infer some information about the location of the submarine landslide by solving the inverse problem after a tsunami has taken place."
"However, the inverse problem is fairly difficult to solve, even when determining the location of the seismic source of a tsunami, and it is not always possible to achieve adequate results. That said, we have already begun a study to that end, and hope to estimate the locations of the landslides and gain insights into their nature," the researcher added.
A new study provides strong evidence that exposure to light pollution alters predator-prey dynamics between mule deer and cougars across the intermountain West, a rapidly growing region where nighttime skyglow is an increasing environmental disturbance.
The University of Michigan-led study, published online Oct. 18 in the journal Ecography, is the first to assess the impacts of light pollution on predator-prey interactions at a regional scale. It combines satellite-derived estimates of artificial nighttime lights with GPS location data from hundreds of radio-collared mule deer and cougars across the intermountain West.
The study found that:
Mule deer living in light-polluted areas are drawn to artificial nighttime lighting, which is associated with green vegetation around homes.
Cougars, also known as mountain lions and pumas, are able to successfully hunt within light-polluted areas by selecting the darkest spots on the landscape to make their kill.
While mule deer that live in dark wildland locations are most active around dawn and dusk, those living around artificial night light forage throughout the day and are more active at night than wildland deer--especially during the summer.
The animal data used in the study were collected by state and federal wildlife agencies across the region. Collation of those records by the study authors yielded what is believed to be the largest dataset on interactions between cougars and mule deer, two of the most ecologically and economically important large-mammal species in the West.
"Our findings illuminate some of the ways that changes in land use are creating a brighter world that impacts the biology and ecology of highly mobile mammalian species, including an apex carnivore," said study lead author Mark Ditmer, formerly a postdoctoral researcher at the University of Michigan School for Environment and Sustainability, now at Colorado State University.
The intermountain West spans nearly 400,000 square miles and is an ideal place to assess how varying light-pollution exposures influence the behavior of mule deer and cougars and their predator-prey dynamics. Both species are widely distributed throughout the region--the mule deer is the cougar's primary prey species--and the region presents a wide range of nighttime lighting conditions.
The intermountain West is home to some of the darkest night skies in the continental United States, as well as some of the fastest-growing metropolitan areas, including Las Vegas and Salt Lake City. Between the dark wildlands and the brightly illuminated cities is the wildland-urban interface, the rapidly expanding zone where homes and associated structures are built within forests and other types of undeveloped wildland vegetation.
For their study, the researchers obtained detailed estimates of nighttime lighting sources from the NASA-NOAA Suomi polar-orbiting satellite. They collected GPS location data for 117 cougars and 486 mule deer from four states: Utah, Arizona, Nevada and California. In addition, wildlife agencies provided locations of 1,562 sites where cougars successfully killed mule deer.
"This paper represents a massive undertaking, and to our knowledge this dataset is the largest ever compiled for these two species," said study senior author Neil Carter, a conservation ecologist at the U-M School for Environment and Sustainability.
Deer in the arid West are attracted to the greenery in the backyards and parks of the wildland-urban interface. Predators follow them there, despite increased nighttime light levels that they would normally shun. Going into the study, the researchers suspected that light pollution within the wildland-urban interface could alter cougar-mule deer interactions in one of two ways.
Perhaps artificial nighttime light would create a shield that protects deer from predators and allows them to forage freely. Alternatively, cougars might exploit elevated deer densities within the wildland-urban interface, feasting on easy prey inside what scientists call an ecological trap.
Data from the study provides support for both the predator shield and ecological trap hypotheses, according to the researchers. At certain times and locations within the wildland-urban interface, there is simply too much artificial light and/or human activity for cougars, creating a protective shield for deer.
An ecological trap occurs when an animal is misled, or trapped, into settling for apparently attractive but in fact low-quality habitat. In this particular case, mule deer are drawn to the greenery of the wildland-urban interface and may mistakenly perceive that the enhanced nighttime lighting creates a predator-free zone.
But the cougars are able to successfully hunt within the wildland-urban interface by carefully selecting the darkest spots on the landscape to make their kill, according to the study. In contrast, cougars living in dark wildland locations hunt in places where nighttime light levels are slightly higher than the surroundings, the researchers found.
"The intermountain West is the fastest-growing region of the U.S., and we anticipate that night light levels will dramatically increase in magnitude and across space," said U-M's Carter. "These elevated levels of night light are likely to fundamentally alter a predator-prey system of ecological and management significance--both species are hunted extensively in this region and are economically and culturally important."
The other authors of the Ecography paper, in addition to Ditmer and Carter, are: David Stoner and Terry Messmer of Utah State University, Clinton Francis of California Polytechnic University, Jesse Barber of Boise State University, James Forester the University of Minnesota, David Choate of the University of Nevada at Las Vegas, Kirsten Ironside and Kathleen Longshore of the U.S. Geological Survey, Kent Hersey and Daniel Olson of the Utah Division of Wildlife Resources, Randy Larson and Brock McMillan of Brigham Young University, Alyson Andreasen of the University of Nevada at Reno, Jon Beckmann of the Wildlife Conservation Society, and Brandon Holton of Grand Canyon National Park.
Funding for the project was provided by NASA; the National Park Service; the U.S. Geological Survey; the Utah Division of Wildlife Resources; the Nevada Department of Wildlife; the Arizona Game and Fish Department; the U.S. Department of Energy; Grand Canyon, Zion and Capitol Reef national parks; the Bureau of Land Management; the U.S. Forest Service; the U.S. Department of Agriculture's Wildlife Services; and the U.S. Fish and Wildlife Service.
Subsidiary funding was provided by the Utah Army National Guard, Kennecott Utah Copper Corp., the African Safari Club of Florida, Utah's Hogle Zoo, and the Utah Chapter of the American Association of Zoo Keepers.
Study: Artificial nightlight alters the predator-prey dynamics of an apex carnivore
A new study, led by the doctors who regularly treat gunshot victims, examined the way the media covers shootings and found that news reports place a disproportionate emphasis on fatal and multiple shootings, while also focusing on uncommon victims, such as women. The researchers fear that the gap between what is covered - and what goes uncovered - in the news could be painting an unrealistic picture of gun violence, which might affect the way the public perceives it. The study was published today in the journal Preventive Medicine.
"As a trauma surgeon, and someone who feels very connected to my patients, I take notice of gun violence coverage in the news--most often the lack thereof. I am particularly saddened when I find there was no media reporting on the shootings that have caused injury and death to my patients, which is most often the case," said the study's lead author, Elinore Kaufman, MD, an assistant professor of Surgery in Traumatology in the Perelman School of Medicine at the University of Pennsylvania. "While I was not surprised to see data on under-reporting in the media, I was startled to see how much it varied related to victim characteristics."
Kaufman and her fellow researchers drew on police reports and information kept by the Gun Violence Archive, a non-profit research group, to monitor media reporting during 2017 inthree different cities: Philadelphia, Cincinnati, and Rochester, NY. Of the 1,801 victims of intentional shootings (outside of self-inflicted shootings), the researchers saw that almost exactly half, 900, were covered in the news.
Of these victims, roughly 83 percent were Black, but just 49 percent of them made the news. Moreover, if the victim was a man, he was about 40 percent less likely to be covered on the news than a woman.
Disparities in news coverage continued when the deadliness of the shootings was examined. Although 16 percent of the victims from the analyzed shootings died, these fatal shootings accounted for 83 percent of the cases covered by the news.
"A vast majority of the victims of gun violence survive, but I don't think the public knows much about people whose lives have been disrupted in so many ways by their injuries, and who need all our support to recover," Kaufman said. "I like to think that more public awareness of the impact of gun violence on survivors would lead to broader support for the services and programs that they need."
Statistics have shown that one in four Americans perceive mass shootings to be the greatest gun violence threat facing their communities, but the study showed that shootings with multiple victims occurred just 22 percent of the time. However, mass shootings were almost six times as likely to make the news.
"This skews our focus toward things like active shooter drills in schools, and away from the kind of community investment that we need to prevent the forms of gun violence that are so much more common," Kaufman said.
There were some differences on the city level data that the study uncovered. Philadelphia had the most shooting victims in 2017 with 1,216 (compared to 407 in Cincinnati and 178 in Rochester), but those victims were also covered the least: only 46 percent of the time (compared to 55 percent in Cincinnati and 65 percent in Rochester).
"I think the news media in any given market has limited space for reporting on violence, and so in areas where violence is common, there's going to be a lot of underreporting. The opposite could be true as well: In areas with little violence, the reporting may be disproportionate," she explained.
While the study focused on the numbers and percentages associated with media reporting on gun violence, Kaufman and her fellow researchers believe that it is just the beginning of the story. Public perception and support are key to making public health policy changes, and media reporting clearly has an influence on them. As such, changing the content of the reports appears key.
That might especially be important as newsrooms are hit by budget cuts and downsizing. With a smaller pool of reporters to cover incidents, shifting the focus of coverage to more truly represent the realities of gun violence could solve issues the study found.
"We understand that reporting community gun violence is an interminable obligation, especially for contracting newsrooms," said senior author Jim McMillan, the director of the Philadelphia Center for Gun Violence Reporting, a project of the Initiative for Better Gun Violence Reporting. "But instead of trying to double down on incident coverage, we recommend that journalists collaborate with other stakeholders to advance best reporting practices such as focusing on evidence-based solutions to the crisis."
So while every instance may not make the news due to the realities of modern newsrooms, such shifts in focus could go a long way toward solving perception issues.
"Many of these reports that we counted were one- or two-liners that tell very little about the humans whose lives are impacted by these shootings," Kaufman said. "We hope to soon study how widely reporters are able to engage more deeply and substantively with the subject, and perhaps even measure the impact of different kinds of stories on readers and watchers of the news."
Earth's history knows catastrophes which are unimaginable for humans. For example, around 66 million years ago an asteroid impact marked the end of the dinosaur era. Long before however, 252 million years ago at the boundary between the Permian and Triassic epochs, Earth witnessed a far more extreme mass extinction event that extinguished about three-quarters of all species on land and some 95 percent of all species in the ocean. Volcanic activity on an enormous scale in today's Siberia has long been debated as a likely trigger of the Permian-Triassic mass extinction, but the exact sequence of events that led to the extinction remained highly controversial. Now, a team of researchers from GEOMAR Helmholtz Centre for Ocean Research Kiel, in collaboration with the Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences and Italian and Canadian universities, provides for the first time a conclusive reconstruction of the key events that led to the mega-catastrophe. Their research also draws bleak lessons for the future. They report about their discoveries in the journal Nature Geoscience.
The international team led by Hana Jurikova studied isotopes of the element boron in the calcareous shells of fossil brachiopods - clam-like organisms - and with it determined the rate of ocean acidification over the Permian-Triassic boundary. Because the ocean pH and atmospheric carbon dioxide (CO2) are closely coupled, the team was able to reconstruct changes in atmospheric CO2 at the onset of the extinction from boron and carbon isotopes. They then used an innovative geochemical model to study the impact of the CO2 injection on the environment. Their findings showed that volcanic eruptions, from the then active flood basalt province "Siberian Traps", released immense amounts of CO2 into the atmosphere. This large CO2 release lasted several millennia and led to a strong greenhouse effect on the late Permian world, causing extreme warming and acidification of the ocean. Dramatic changes in chemical weathering on land altered productivity and nutrient cycling in the ocean, and ultimately led to vast de-oxygenation of the ocean. The resulting multiple environmental stressors combined to wipe out a wide variety of animal and plant groups. Dr. Jurikova says: "We are dealing with a cascading catastrophe in which the rise of CO2 in the atmosphere set off a chain of events that successively extinguished almost all life in the seas.".
Hana Jurikova adds: "Ancient volcanic eruptions of this kind are not directly comparable to anthropogenic carbon emissions, and in fact all modern fossil fuel reserves are far too insufficient to release as much CO2 over hundreds of years, let alone thousands of years as was released 252 million years ago. But it is astonishing that humanity's CO2 emission rate is currently fourteen times higher than the annual emission rate at the time that marked the greatest biological catastrophe in Earth's history".
A large part of the work was done by the researcher at GEOMAR in Kiel, but she later joined the GFZ (Section 4.3) in Potsdam, and the "icing on the cake" for her were the results from a collaboration with the SIMS laboratory led by Michael Wiedenbeck at the GFZ (Section 3.1). Using the state-of-the-art large-geometry secondary ion mass spectrometer (SIMS), the isotopic composition of the shells could be measured directly on the specimens at the micrometer-scale. This made it possible to determine the boron isotopic composition even in the smallest fragments of brachiopod shells. Depending on the degree of acidification of the seas, the calcareous shells of the organisms living in them differ ever so slightly in their chemical composition. In this way, the pH value of long vanished oceans could be determined in the remains of the shells preserved as fossils in the rock record.
This work is part of the 'BASE-LiNE Earth' Innovative Training Network (ITN) funded by the European Union's Horizon 2020 research and innovation programme (No 643084).
Jurikova H., Gutjahr M., Wallmann K., Flögel S., Liebetrau V., Posenato R., Angiolini L., Garbelli C., Brand U., Wiedenbeck M., Eisenhauer A. (2020): Permian-Triassic mass extinction pulses driven by major marine carbon cycle perturbations. Nature Geoscience, https://www.nature.com/articles/s41561-020-00646-4.
While plastics recycling is not new science, current processes don't make it economically worthwhile-- waste plastics get "down-cycled" into lower grade, less useful material. It's a challenge that continues to be an obstacle in tackling a growing global pollution crisis in single use plastics.
A multi-institutional team of scientists led by the U.S. Department of Energy's Ames Laboratory has developed a first-of-its-kind catalyst that is able to process polyolefin plastics such as polyethylene and polypropylene, types of polymers widely used in things like plastic grocery bags, milk jugs, shampoo bottles, toys, and food containers. The process results in uniform, high-quality components that can be used to produce fuels, solvents, and lubricating oils, products that have high value and could potentially turn these and other used plastics into an untapped resource.
"We've made a big step forward with this work," said Aaron Sadow, a scientist at Ames Laboratory and the Director of the Institute for Cooperative Upcycling of Plastics (iCOUP). "We hypothesized that we could borrow from nature, and mimic the processes by which enzymes precisely break apart macromolecules like proteins and cellulose. We succeeded in doing that, and we're excited to pursue optimizing and developing this process further."
The unique process relies on nanoparticle technology. Ames Lab scientist Wenyu Huang designed a mesoporous silica nanoparticle consisting of a core of platinum with catalytic active sites, surrounded by long silica pores, or channels, through which the long polymer chains thread through to the catalyst. With this design, the catalyst is able to hold on to and cleave the longer polymer chains into consistent, uniform shorter pieces that have the most potential to be upcycled into new, more useful end products.
"This type of controlled catalysis process has never before been designed based on inorganic materials," Huang, who specializes in the design of structurally well-defined nano-catalysts. "We were able to show that the catalytic process is capable of performing multiple identical deconstruction steps on the same molecule before releasing it."
Ames Laboratory's solid state NMR expert Fred Perras' measurements allowed the team to scrutinize the catalyst's activity at the atomic scale, and confirmed that the long polymer chains moved readily through the catalyst pores in the manner resembling the enzymatic processes that the scientists were aiming to emulate.
This research will be expanded and continued under direction of the Institute for Cooperative Upcycling of Plastics (iCOUP), led by Ames Laboratory. iCOUP is an Energy Frontier Research Center consisting of scientists from Ames Laboratory, Argonne National Laboratory, UC Santa Barbara, University of South Carolina, Cornell University, Northwestern University, and the University of Illinois Urbana-Champaign.
The research is further discussed in the paper, "Catalytic upcycling of high-density polyethylene via a processive mechanism," authored by Akalanka Tennakoon, Xun Wu, Alexander L. Paterson, Smita Patnaik, Yuchen Pei, Anne M. LaPointe, Salai C. Ammal, Ryan A. Hackler, Andreas Heyden, Igor I. Slowing, Geoffrey W. Coates, Massimiliano Delferro, Baron Peters, Wenyu Huang, Aaron D. Sadow, and Frédéric A. Perras; and published in Nature Catalysis.
Ames Laboratory is a U.S. Department of Energy Office of Science national laboratory operated by Iowa State University. Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global problems. DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.
Titled Sex Education in the Mosque, the program "addressed sex education and HIV prevention with a primary focus on abstinence and making self-empowered choices," according to the new research by Shaakira Abdullah, DNP, FNP-BC, of Widener University, Chester, Pa., and colleagues. They report on the development and initial evaluation of their program: the first evidence-based curriculum to address sexual education in the Muslim community.
Teens Learn About Sex and Relationships - With a Focus on Muslim Values
Islamic teachings focus on the value of chastity and forbid having sex before marriage. But many Muslim parents do not talk about sex with their children. "Refraining from discussing issues of sexuality in the home in an effort to prevent promiscuity often backfires and leads adolescents to learn from unreliable sources and engage in risky behaviors, potentially exposing themselves to HIV/STIs or teen pregnancy," Dr. Abdullah and coauthors write. They cite statistics showing that Muslim adolescents have risky sexual behaviors similar to their non-Muslim peers.
Sex Education in the Mosque was designed as a comprehensive sex education program for Muslim youth and adolescents, grounded in the framework of Islamic teachings. The authors report their experience with initial implementation of the program in New Jersey, home to the second-largest Muslim population in the United States, with 18 adolescent Muslim females, average age 16 years, at a mosque in Newark. Mosques were targeted to recruit participants because of their integral role in lifelong education in Muslim communities. The program was implemented with the full support of mosque Imams and administrators.
On pretest questionnaires, the young women had low understanding of HIV, STIs, and pregnancy. Posttest questionnaires showed significant gains in knowledge, which were well-maintained at three months' follow-up.
"There was also an increase in positive attitudes and intentions to abstain from sex before marriage on the posttests," the researchers write. All of the young women gave the program positive ratings; one teen wrote that she appreciated learning "many methods on how to be true to ourselves and cool at the same time!"
The program was adapted from an established curriculum that uses social and behavior theories to educate young people about their sexuality. Dr. Abdullah and colleagues integrated Muslim values and a focus on having a strong Islamic identity to strengthen teens' self-confidence and ability to make healthy decisions. "The program distinguished itself from typical abstinence-based programs because it portrayed sex as a pleasurable and natural experience," according to the authors.
"This project laid the groundwork for creating an effective curriculum that can address Muslim youth's unique needs," Dr. Abdullah and coauthors write. They also discuss important lessons for future implementations: many parents felt their daughters didn't need sex education or misunderstood the purpose of the program. The researchers plan to incorporate parental education sessions into future programs.
In response to interest in sex education and HIV prevention from other communities, Dr. Abdullah has initiated a nonprofit organization called Love Beyond Love, dedicated to strengthening and expanding the program. She and her coauthors conclude: "Muslim youth have the power and potential to hold themselves to a higher standard when given the opportunity to access knowledge, confidence, and skills needed to meet today's challenges."
The Journal of the Association of Nurses in AIDS Care(JANAC) is a peer-reviewed, international nursing journal that covers the full spectrum of the global HIV epidemic, focusing on prevention, evidence-based care management, interprofessional clinical care, research, advocacy, policy, education, social determinants of health, epidemiology, and program development. JANAC functions according to the highest standards of ethical publishing practices and offers innovative publication options, including Open Access and prepublication article posting, where the journal can post articles before they are published with an issue.
About the Association of Nurses in AIDS Care
Since 1987, the Association of Nurses in AIDS Care (ANAC) has been the leading nursing organization responding to HIV/AIDS. The mission of ANAC is to foster the professional development of nurses and others involved in the delivery of health care for persons at risk for, living with, and/or affected by the human immunodeficiency virus (HIV) and its co-morbidities. ANAC promotes the health, welfare and rights of people living with HIV around the world.
About Wolters Kluwer
Wolters Kluwer (WKL) is a global leader in professional information, software solutions, and services for the clinicians, nurses, accountants, lawyers, and tax, finance, audit, risk, compliance, and regulatory sectors. We help our customers make critical decisions every day by providing expert solutions that combine deep domain knowledge with advanced technology and services.
Wolters Kluwer reported 2019 annual revenues of €4.6 billion. The group serves customers in over 180 countries, maintains operations in over 40 countries, and employs approximately 19,000 people worldwide. The company is headquartered in Alphen aan den Rijn, the Netherlands.
Wolters Kluwer provides trusted clinical technology and evidence-based solutions that engage clinicians, patients, researchers and students with advanced clinical decision support, learning and research and clinical intelligence. For more information about our solutions, visit https://www.wolterskluwer.com/en/health and follow us on LinkedIn and Twitter @WKHealth.
HERSHEY, Pa. -- Certain oral antiseptics and mouthwashes may have the ability to inactivate human coronaviruses, according to a Penn State College of Medicine research study. The results indicate that some of these products might be useful for reducing the viral load, or amount of virus, in the mouth after infection and may help to reduce the spread of SARS-CoV-2, the coronavirus that causes COVID-19.
Craig Meyers, distinguished professor of microbiology and immunology and obstetrics and gynecology, led a group of physicians and scientists who tested several oral and nasopharyngeal rinses in a laboratory setting for their ability to inactivate human coronaviruses, which are similar in structure to SARS-CoV-2. The products evaluated include a 1% solution of baby shampoo, a neti pot, peroxide sore-mouth cleansers, and mouthwashes.
The researchers found that several of the nasal and oral rinses had a strong ability to neutralize human coronavirus, which suggests that these products may have the potential to reduce the amount of virus spread by people who are COVID-19-positive.
"While we wait for a vaccine to be developed, methods to reduce transmission are needed," Meyers said. "The products we tested are readily available and often already part of people's daily routines."
Meyers and colleagues used a test to replicate the interaction of the virus in the nasal and oral cavities with the rinses and mouthwashes. Nasal and oral cavities are major points of entry and transmission for human coronaviruses. They treated solutions containing a strain of human coronavirus, which served as a readily available and genetically similar alternative for SARS-CoV-2, with the baby shampoo solutions, various peroxide antiseptic rinses and various brands of mouthwash. They allowed the solutions to interact with the virus for 30 seconds, one minute and two minutes, before diluting the solutions to prevent further virus inactivation. According to Meyers, the outer envelopes of the human coronavirus tested and SARS-CoV-2 are genetically similar so the research team hypothesizes that a similar amount of SARS-CoV-2 may be inactivated upon exposure to the solution.
To measure how much virus was inactivated, the researchers placed the diluted solutions in contact with cultured human cells. They counted how many cells remained alive after a few days of exposure to the viral solution and used that number to calculate the amount of human coronavirus that was inactivated as a result of exposure to the mouthwash or oral rinse that was tested. The results were published in the Journal of Medical Virology.
The 1% baby shampoo solution, which is often used by head and neck doctors to rinse the sinuses, inactivated greater than 99.9% of human coronavirus after a two-minute contact time. Several of the mouthwash and gargle products also were effective at inactivating the infectious virus. Many inactivated greater than 99.9% of virus after only 30 seconds of contact time and some inactivated 99.99% of the virus after 30 seconds.
According to Meyers, the results with mouthwashes are promising and add to the findings of a study showing that certain types of oral rinses could inactivate SARS-CoV-2 in similar experimental conditions. In addition to evaluating the solutions at longer contact times, they studied over-the-counter products and nasal rinses that were not evaluated in the other study. Meyers said the next step to expand upon these results is to design and conduct clinical trials that evaluate whether products like mouthwashes can effectively reduce viral load in COVID-19-positive patients.
"People who test positive for COVID-19 and return home to quarantine may possibly transmit the virus to those they live with," said Meyers, a researcher at Penn State Cancer Institute. "Certain professions including dentists and other health care workers are at a constant risk of exposure. Clinical trials are needed to determine if these products can reduce the amount of virus COVID-positive patients or those with high-risk occupations may spread while talking, coughing or sneezing. Even if the use of these solutions could reduce transmission by 50%, it would have a major impact."
Future studies may include a continued investigation of products that inactive human coronaviruses and what specific ingredients in the solutions tested inactivate the virus.
Janice Milici, Samina Alam, David Quillen, David Goldenberg and Rena Kass of Penn State College of Medicine and Richard Robison of Brigham Young University also contributed to this research.
The research was supported by funds from Penn State Huck Institutes for the Life Sciences. The researchers declare no conflict of interest.
When the air outside is bad, office workers are more likely to order food delivery than go out for lunch, which in turn increases plastic waste from food packaging, according to a study by researchers from the National University of Singapore (NUS).
Associate Professor Alberto Salvo from the Department of Economics at the NUS Faculty of Arts and Social Sciences and an author of the study, said, "Plastic waste is a growing global environmental concern. While we see more research on the impact plastic pollution is having on the natural environment, there has been less work trying to understand the human behaviour that drives plastic pollution. This is where our study seeks to contribute - finding a strong causal link between air pollution and plastic waste through the demand for food delivery. Air quality in the urban developing world is routinely poor and in the past decade, the food delivery industry has been growing sharply. The evidence we collected shows a lot of single-use plastic in delivered meals, from containers to carrier bags."
The results of the study were published in the journal Nature Human Behaviour.
Air pollution drives demand for food delivery services
The NUS team, including Assoc Prof Liu Haoming and Assoc Prof Chu Junhong, focused their study on China, which is among the world's largest users of online food delivery platforms, with 350 million registered users. An estimated 65 million meal containers are discarded each day across China, with office workers contributing over one-half of demand.
The study surveyed the lunch choices of 251 office workers repeatedly over time (each worker for 11 workdays) in three often smog-filled Chinese cities - Beijing, Shenyang and Shijiazhuang - between January and June 2018. To complement the office-worker survey, the researchers also accessed the 2016 Beijing order book of an online food delivery platform, which broadly represented all market segments served by the food delivery industry - collecting observational data on 3.5 million food delivery orders from about 350,000 users.
Data from the survey and order book were then compared with PM2.5 measurements (fine particles less than 2.5 micrometres in diameter) during lunchtime periods from the air-monitoring network in all three cities. It was observed that PM2.5 levels during these periods were often well above the 24-hour US National Ambient Air Quality Standard of 35 μg/m³, making pollution highly visible. The researchers were careful to control for confounding factors such as economic activity.
Both data sources indicated a strong link between PM2.5 (haze) pollution and food delivery consumption. Correcting for weather and seasonal influences, the firm's order book revealed that a 100 μg/m³ increase in PM2.5 raised food delivery consumption by 7.2 per cent. The impact of a 100 μg/m³ PM2.5 shift on office workers' propensity to order delivery was six times larger, at 43 per cent.
Assoc Prof Chu from the Department of Marketing at NUS Business School elaborated, "Faced with smog or haze outside, a typical office worker at lunchtime can avoid exposure only by ordering food to be delivered to his or her doorstep. A broader base of consumers has more alternatives to avoiding the outdoor environment on a polluted day, for example, by using a home kitchen when at home. This explains why the impact of air pollution on food delivery is smaller in the firm's order book study than what we observed among workers, particularly those without access to a canteen in their office building. Nevertheless, we find the impact to be economically large also among the broader population served by the food delivery platform that we examined."
Air pollution control brings plastic waste co-benefits
Over 3,000 photos of meals were submitted by office workers, enabling the NUS team to quantify how much disposable plastic varies across different lunch choices, in particular, meals eaten at the restaurant versus those delivered to the office. The researchers estimated that a 100 μg/m³ PM2.5 increase raised a meal's disposable plastic use by 10 grams on average - equivalent to about one-third the mass of a plastic container. Photographs that were published as part of the study indicated that the average delivered meal used 2.8 single-use plastic items and an estimated 54 grams of plastic. The average dine-in meal used an estimated 6.6 grams of plastic, such as in chopstick sleeves or bottles.
Based on the order book, the researchers also estimated that on a given day, if all of China were exposed to a 100 μg/m³ PM2.5 increase in dose as is routinely observed in Beijing, 2.5 million more meals would be delivered, requiring an additional 2.5 million plastic bags and 2.5 million plastic containers.
Assoc Prof Liu from the Department of Economics said, "Our findings probably apply to other typically polluted developing-nation cities, such as in Bangladesh, India, Indonesia and Vietnam. Waste management practices vary widely, with wind blowing plastic debris away from uncovered landfills or plastic being discarded into rivers and from there into the ocean. So, with eight million tonnes of plastic estimated to enter the seas each year, our study speaks to a wider issue. Individuals protect themselves from - and show their distaste for - air pollution by ordering food delivery which often comes in plastic packaging. It is evident from our study that air pollution control can reduce plastic waste."
Moving forward, the researchers will continue working on behavioural feedback by which pollution begets pollution: in particular, to defend themselves from environmental pollution, humans use more natural resources and pollute more. As a recent example, the researchers note how concern over exposure to COVID-19 has led to booming demand for home-delivered meals which are predominantly packaged in plastic. They hope that their work will add to the voices calling for more environmentally friendly packaging and improved waste management.
Worldwide demand for food from the tropics that meets higher environmental and social standards has risen sharply in recent years. Consumers often have to make ethically questionable decisions: products may be available to the global market through child labour, starvation wages or environmental destruction. Building on an interdisciplinary project in Peru, an international research team with the participation of the University of Göttingen has now published an overview article on the transition to responsible, high-quality cocoa production. Chocolate is made from cocoa beans, and because cocoa is originally from Peru, using indigenous varieties means a premium price can be charged. A large cooperative for small-holder farmers in northern Peru stands for social and ecological improvements with the help of organic and fair-trade certification, as well as the cultivation of native varieties in species-rich cocoa agroforestry systems. The work was published as a "Perspective" article in the journal Trends in Ecology and Evolution.
Shade trees in traditional cocoa agroforestry systems improve conditions for cocoa growth and promote biodiversity, for instance of birds. However, these trees are increasingly being removed to increase productivity, even though moderate, partial shade does not significantly reduce productivity. In addition, proven high-yielding varieties are imported, although there are unique indigenous varieties in Peru that may be associated with a particular trade advantage. The researchers' project group is working together with the cooperative Norandino Ltda. in Piura, northern Peru, which is committed to working towards developing high social and ecological standards. It represents 5,400 smallholder farmers and stands for sustainable production that pursues both ecological and economic goals. Furthermore, the cooperative is committed to fighting all forms of discrimination. The result is ecologically certified and fair-trade chocolate of a high standard, which achieves up to twice the regular market price, protects smallholder farmers against market fluctuations and moves towards the greater use of local cocoa bean varieties in the future.
Dr Bea Maas, first author of the article and now at the University of Vienna, emphasises: "Large cooperatives that stand for high social, economic and ecological standards in production should receive more support." Carolina Ocampo-Ariza and Professor Teja Tscharntke from the Agroecology group at the University of Göttingen add: "Such exemplary initiatives that benefit the livelihoods of smallholder farmers while maximising nature conservation should be the focus of interdisciplinary research now more than ever before."
A STUDY into the impact of the COVID-19 lockdown on the mental health of people in Soweto has found a significant link between symptoms of depression and how likely people felt they were to be infected.
Researchers also found that both the perceived risk of infection and the likelihood of depression and anxiety increased among people who had suffered childhood trauma and among those already suffering the effects of poverty and deprivation.
Associations between depression and issues such as hunger, violence, poor healthcare, and high rates of poverty have long been recognised, but this study is the first to look at the mental health effects of the pandemic and national lockdown in South Africa under those conditions.
Researchers spoke to more than 200 adults who were already part of a long-term health study in Soweto. This had surveyed 957 people in the months before the pandemic, measuring their risk of mental ill-health, including depression, by asking them to score their mood, feelings, and behaviour. The participants were also asked about day-to-day adversity, such as family strife, poverty, deprivation, and violence; about their ways of coping, including support from friends, family, and church; and about adverse experiences in childhood like abuse, neglect, and household dysfunction.
The follow-up survey was carried out over the phone after the first six weeks of lockdown. It asked people to score themselves against major symptoms of depression during the previous month, assessed their knowledge of COVID-19 and how to protect against it, and asked whether they thought they were at less risk, the same risk or a greater risk than others.
The results, published in the Cambridge journal, Psychological Medicine, showed people were two times as likely to experience significant depressive symptoms for every step increase in their perceived risk from COVID-19. It was also found that those with a history of childhood trauma were more likely to have a higher perceived risk of contracting the virus.
In all, 14.5 per cent of those surveyed were found to be at risk of depression, with 20 per cent indicating that COVID-19 caused them deep worry, anxiety, or led to them 'thinking too much' about the virus and its impact.
While the majority did not think COVID-19 affected their mental health, both the data and what people said about its impact on their lives suggested otherwise.
Dr. Andrew Wooyoung Kim of Northwestern University, who co-directed the study for the Developmental Pathways for Health Research Unit at the University of the Witwatersrand, said: "This discrepancy may be due to different ideas of mental health, including mental health stigma.
"While participants believed that the pandemic did not affect their mental health or their 'mind', the strong relationship between perceived risk and depressive symptoms raises the concern that they may not be aware of the potential threats to their mental health during COVID-19."
These threats were amplified by other pre-existing adversities, said Dr Kim and his colleagues, including hunger and violence, an overburdened healthcare system, a high prevalence of chronic and infectious disease, and alarming rates of poverty and unemployment.
They argue that the pressures of COVID-19 and lockdown risk adding to the already high levels of mental illness among people in South Africa, where one in three experience some kind of mental disorder in their lifetimes and where only 27 per cent of patients with a severe mental illness receive treatment.
Dr Kim said: "Our study re-emphasizes the importance of prioritizing and provisioning accessible mental health resources for resource-limited communities in Soweto and across South Africa."