Culture

New risk prediction model could identify those at higher risk of pancreatic cancer

Bottom Line: A risk prediction model that combined genetic and clinical factors with circulating biomarkers identified people at significantly higher than normal risk of pancreatic cancer.

Journal in Which the Study was Published: Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research

Author: Peter Kraft, PhD, professor of epidemiology at the Harvard T.H. Chan School of Public Health in Boston.

Background: "Pancreatic cancer is a particularly deadly cancer, with about 80 percent of patients diagnosed with advanced, incurable disease," said Kraft. "Catching it at an earlier stage makes it more likely that surgery will be an option, increasing the chances of survival."

Kraft explained that existing screening techniques, such a magnetic resonance imaging (MRI), are not recommended for the general public because they may generate excessive rates of false positives. They are most appropriate for people at higher risk of pancreatic cancer, and therefore, improving identification of the high-risk population could improve tailored prevention and screening efforts, he said.

Risk factors for pancreatic cancer include family history, chronic conditions like diabetes and pancreatitis, and smoking. Kraft said prospective studies have shown that certain circulating biomarkers tied to insulin resistance have also been shown to influence risk. "These factors have been investigated individually, and in this study, we wanted to examine the combined effect of clinical factors, common genetic predisposition variants, and circulating biomarkers."

How the Study was Conducted:
The study examined data from four large prospective cohort studies: the Health Professionals Follow-up Study; the Nurses' Health Study; the Physicians' Health Study; and the Women's Health Initiative. They analyzed data from 500 patients diagnosed with primary pancreatic adenocarcinoma between 1984 and 2010, as well as 1,091 matched controls. The study enrolled only U.S. non-Hispanic white participants, because genomic risk variants have been confirmed in the white population but not in other groups, Kraft said.

The researchers collected data on lifestyle and clinical characteristics from patient questionnaires; blood samples; and genomic DNA from peripheral blood leukocytes of the participants. They calculated a weighted genetic risk score based on data from two large genome-wide association studies.

The researchers developed three relative risk models for men and women separately. One featured only clinical factors; one added the weighted genetic risk score to the clinical factors; and the third added biomarkers proinsulin, adiponectin, IL-6, and total branched-chain amino acids.

Results: Kraft said that each new level of data improved "model fit," allowing for more accurate identification of pancreatic cancer risk.

Ultimately, the models identified subsets of participants who were at three-fold or higher increased risk of pancreatic cancer than the general population. The model that featured only clinical characteristics identified 0.2 percent of men and 1.5 percent of women who were at three-fold or higher increased risk. The model that combined clinical and genetic factors identified 0.3 percent of men and 2.3 percent of women at three-fold or greater risk. The model that added weighted genetic risk score and circulating biomarkers identified 1.8 percent of men and 0.7 percent of women who were at three-fold or higher increased risk. The final integrated model identified 2.0 percent of men and 2.3 percent of women who had at least three times greater than average risk in 10 years of follow-up. The individuals in the top 1 percent of risk carried a 4 percent lifetime risk of pancreatic cancer.

Author's Comments: While this model would have to be confirmed and studied in other populations, Kraft said the study indicates that combining biomarkers with clinical and genetic factors can result in better identification of the people who could benefit from screening and early detection of pancreatic cancer.

"Like most cancers, pancreatic cancer is multifactorial," Kraft said. "The more we are able to combine information from multiple domains, the better we will become at identifying those who could benefit from screening."

Study Limitations: The study's key limitation is that family history of pancreatic cancer was not collected from most participants, making it difficult to estimate the relative risk of this important factor. The impact of smoking status also could not be directly estimated, as the contributing studies matched patients with pancreatic cancer to cancer-free individuals based on their smoking status.

Credit: 
American Association for Cancer Research

A history of cannabis dependence associated with many negative mental health outcomes

More than 1% of Canadians have been dependent on cannabis at some point in their lives. Despite the fact that marijuana use is expected to grow with the recent legalization of recreational cannabis in Canada, little research has focused on factors associated with recovery from addiction.

New research published online this month in the journal Advances in Preventive Medicine found that Canadians with a history of cannabis dependence are much less likely to be in excellent mental health and much more likely to have some form of mental illness or substance dependence compared to those who have never been dependent on cannabis.

The study compared 336 Canadians with a history of cannabis dependence to 20,441 who had never been addicted to the substance. The data were drawn from Statistics Canada's 2012 Canadian Community Health Survey-Mental Health.

"Our findings illustrate that for many adults, a history of cannabis dependence casts a very long shadow, with a wide range of associated negative mental health outcomes" says lead author Esme Fuller-Thomson, professor at the University of Toronto's Factor-Inwentash Faculty of Social Work (FIFSW) and Director of the Institute for Life Course and Aging.

More than a quarter (28%) of those with a history of cannabis dependence were still dependent on cannabis, while almost one-half (47%) had some form of mental illness or substance dependence, compared to only 8% among those without a history of cannabis dependence.

Overall, 74% of those without a history of dependence were in excellent mental health, while only 43% of those with a history of dependence were. To be considered in excellent mental health, subjects had to report: 1) almost daily happiness or life satisfaction in the past month, 2) high levels of social and psychological well-being in the past month, and 3) freedom from all forms of substance dependence, depressive and generalized anxiety disorder and serious suicidal thoughts for at least the preceding full year.

Social support was strongly associated with remission from cannabis attendance and achieving excellent mental health.

"It is important to consider ways to best facilitate social integration and social support for clients who are recovering from cannabis addiction," says co-author Janany Jayanthikumar, a Master of Social work graduate from U of T. "Clinicians may be more effective if they expand the focus of their treatment for substance dependence to include strategies to assist clients in creating and maintaining healthy social connections."

In addition, women with a history of cannabis dependence were more likely than men to be in remission and to have excellent mental health.

"Women may experience more acutely negative physical, mental, and social consequences of substance use than men which may motivate them to discontinue use," says co-author Melissa Redmond, Assistant Professor of Social Work at Carleton University. "Women may also decrease substance use during pregnancy or periods of child-rearing due to side effects and associated feelings of responsibility or guilt."

The study also found that with each decade of age, adults had double the likelihood of achieving both remission and excellent mental health.

"Decreases in impulsivity, increased role responsibility, awareness of the impact of drug use on health as well as negative social consequences are thought to play a role in remission among older individuals." says co-author Senyo Agbeyaka, a recent Master of Social Work graduate from U of T.

While the Statistics Canada survey used for the study did not gather information on what interventions, if any, those with cannabis dependence received, other research indicates that combined treatments, such as motivational enhancement therapy and cognitive behavioral therapy, are quite successful in reducing cannabis use as well as dependence related symptoms.

Previous research indicates that among cannabis users, dependence is high. A 2013 nationally representative US study found that almost one-third (31%) of current cannabis users were cannabis dependent.

"It is important to remember that the legalization of cannabis is not solely about a profitable new business," warned Fuller-Thomson who is also cross-appointed to the Department of Family and Community Medicine and the Faculty of Nursing at U of T. "With more users and subsequently more people who are cannabis dependent, there will be very serious long-term mental health repercussions that individuals, families and the health care systems must address."

Credit: 
University of Toronto

New study reveals life's earliest evolution was more complicated than previously suspected

image: Phylogenetic tree diagrams form the basis of understanding microbial evolution. Long branches between the two domains in some trees may reflect a period of very rapid evolution, billions of years ago.

Image: 
S. Shiobara, S. McGlynn, ELSI, CC BY 4.0

Biologists have long hoped to understand the nature of the earliest living organisms on Earth. If they could, they might then be able to say something about how, when, and where life arose on Earth, and perhaps by extension, whether life is common in the Universe.

Previous studies have suggested this information can be obtained by comparing the genes present in modern organisms. New research indicates that only limited information can be derived using this approach.

Biologists classify all living organisms into three major groups they call 'domains.' Two of these domains--the Bacteria and the Archaebacteria--consist of single-celled organisms, while the third--the Eukaryota--includes most of the larger, multicellular organisms we are all familiar with: fungi, plants and animals including ourselves. Of the three domains, the Eukaryota almost certainly evolved the most recently, but questions remain about which of the two single-celled domains arose first in the history of life.

Over forty years ago, American biologists Carl Woese and George Fox suggested that these two domains both emerged from a more primitive organism or group of organisms scientists now call LUCA, or the Last Universal Common Ancestor. Scientists would love to be able to say something concrete about what LUCA was like, what types of environment it lived in, and how it made its living.

New research from Tokyo Tech and the Max Planck Institute suggests understanding early life may be trickier than previously thought.

The research, published in the advanced access edition of the journal Molecular Biology and Evolution, was carried out by Sarah Berkemer, based at the Max Planck Institute for Mathematics in the Sciences in Leipzig, Germany, and Shawn McGlynn from the Earth-Life Science Institute at the Tokyo Institute of Technology in Japan comes in. Their analyses confirm other work which suggested that only a limited understanding of the lifestyle of the most ancient cells can be derived from DNA comparison. Although this is a disappointing result for evolutionary biologists, it is important to understand what can and cannot be known from the data that scientists are able to gather from modern organisms. Berkemer and McGlynn's work does supply one silver lining however; while it is clear that we don't know what the first organisms metabolised or where they lived, their work provides insight into how quickly they may have evolved billions of years ago.

To do so, Berkemer and McGlynn analyzed thousands of phylogenetic trees derived from the comparison of DNA similarity data from thousands of microorganisms to try to identify the oldest genes and when they might have evolved, and to understand how genes move between organisms to shed light on the nature of LUCA. Their careful analysis showed that early in life's history, different gene types changed at different rates. This suggests that early mutation rates were much higher than at present and there has been a significant contribution of 'gene jumping' over time which makes a simple interpretation of the early 'family tree' of life misleading. They concluded that previous studies sometimes vastly under-sampled the available data and that the data cannot resolve these questions, but that it does show that early evolution was wildly different from what it is at present.

Professor McGlynn explains, "A fundamental question in biology is what were the first life forms on Earth. There are two basic ways to try and address this. First, we can use the comparison of gene sequences to try and understand which ones seem most ancient. Second, we can look for evidence biology may have left in the geological record." McGlynn says this work shows that although it is clear there is a fuzzy yet remarkable general outline of a family tree of life in the available DNA sequence data, there has been so much evolutionary change that it is still as of yet impossible to say how the earliest organisms made their living or in what types of environments they lived. This is because the signal is simply too noisy due to this early genetic scrambling. As a result, we are still a long way from understanding what the most primitive organisms on Earth were like or the sorts of environments they lived in.

Importantly, however, this study marks the first time scientists have been able to say something about the pace of early evolution. This work shows there is a detectable signal of very rapid early evolution, thus, while we may not know exactly what early organisms were like, it seems likely life was mutating and evolving very quickly early on. Nevertheless, McGlynn believes it is still amazing that this limited information can be understood at all, that it still tells us important things about the evolution of life on Earth, and suggests we need to develop new ways of looking at available DNA data to find novel techniques of learning what Earth's earliest life was like.

Credit: 
SMBE Journals (Molecular Biology and Evolution and Genome Biology and Evolution)

Windows will soon generate electricity, following solar cell breakthrough

image: A semi-transparent perovskite solar cell with contrasting levels of light transparency.

Image: 
Dr Jae Choul Yu

Semi-transparent solar cells that can be incorporated into window glass are a "game-changer" that could transform architecture, urban planning and electricity generation, Australian scientists say in a paper in Nano Energy.

The researchers - led by Professor Jacek Jasieniak from the ARC Centre of Excellence in Exciton Science (Exciton Science) and Monash University - have succeeded in producing next-gen perovskite solar cells that generate electricity while allowing light to pass through. They are now investigating how the new technology could be built into commercial products with Viridian Glass, Australia's largest glass manufacturer.

This technology will transform windows into active power generators, potentially revolutionising building design. Two square metres of solar window, the researchers say, will generate about as much electricity as a standard rooftop solar panel.

The research was also supported by the Australian Renewable Energy Agency (ARENA).

The idea of semi-transparent solar cells is not new, but previous designs have failed because they were very expensive, unstable or inefficient.

Professor Jasieniak and colleagues from Monash's Materials Science and Engineering Department and Australia's national science agency, CSIRO, used a different approach.

They used an organic semiconductor that can be made into a polymer and used it to replace a commonly used solar cell component (known as Spiro-OMeTAD), which shows very low stability because it develops an unhelpful watery coating. The substitute produced astonishing results.

"Rooftop solar has a conversion efficiency of between 15 and 20%," Jacek said.

"The semi-transparent cells have a conversion efficiency of 17%, while still transmitting more than 10% of the incoming light, so they are right in the zone. It's long been a dream to have windows that generate electricity, and now that looks possible."

Co-author and CSIRO research scientist, Dr Anthony Chesman, said the team is now working on scaling up the manufacturing process.

"We'll be looking to develop a large-scale glass manufacturing process that can be easily transferred to industry so manufacturers can readily uptake the technology," he said.

Solar windows will be a boon for building owners and residents, and will bring new challenges and opportunities for architects, builders, engineers and planners.

"There is a trade-off," explained Professor Jasieniak, "The solar cells can be made more, or less, transparent. The more transparent they are, the less electricity they generate, so that becomes something for architects to consider."

He added that solar windows tinted to the same degree as current glazed commercial windows would generate about 140 watts of electricity per square metre.

The first application is likely to be in multistorey buildings.

Large windows deployed in high-rise buildings are expensive to make. The additional cost of incorporating the semi-transparent solar cells into them will be marginal.

"But even with the extra spend, the building then gets its electricity free!" Professor Jasieniak said.

"These solar cells mean a big change to the way we think about buildings and the way they function. Up until now every building has been designed on the assumption that windows are fundamentally passive. Now they will actively produce electricity.

"Planners and designers might have to even reconsider how they position buildings on sites, to optimise how the walls catch the sun."

Lead author Dr Jae Choul Yu, also from Exciton Science and Monash, added that more efficiency gains would flow from further research.

"Our next project is a tandem device," he said. "We will use perovskite solar cells as the bottom layer and organic solar cells as the top one."

As to when the first commercial semi-transparent solar cells will be on the market, "that will depend on how successful scaling of the technology will be, but we are aiming to get there within 10 years," said Professor Jasieniak.

Jatin Khanna, Operations Manager for Viridian Glass, added: "The development of such solar windows presents an opportunity that could translate into the new glass innovations and technologies going forward."

Credit: 
ARC Centre of Excellence in Exciton Science

New report: Inclusive food systems needed to boost development, resilience

image: Report Cover

Image: 
IFPRI

Washington, D.C. - The rapid spread of COVID-19 and efforts to contain it are generating growing concerns that food insecurity, malnutrition, and poverty may escalate, particularly among marginalized people in the developing world. To build more resilient, climate-smart, and healthy food systems that help people withstand these types of shocks policymakers must prioritize making them inclusive, according to the 2020 Global Food Policy Report, released earlier this month by the International Food Policy Research Institute (IFPRI).

"Food systems provide opportunities to improve food and nutrition security, generate income, and drive inclusive economic growth, but even in prosperous times too many people are excluded from fully participating in them and securing these benefits," said Johan Swinnen, director general of IFPRI. "In times of crisis like today, inclusion is an even greater imperative for protecting the most vulnerable."

The report highlights the central role that inclusive food systems play in meeting global goals to end poverty, hunger, and malnutrition, and offers recommendations for making food systems more inclusive for four marginalized groups - smallholders, women, youth, and conflict-affected people - as well as analysis on transforming national food system.

More than 60% of people in low income countries are employed in agriculture and smallholders comprise more than 70% of farm units in Africa south of the Sahara and 85% of farms in South Asia. The rapid expansion of food markets across Africa and Asia offers tremendous potential for many of these smallholders to benefit if they can increase farm production or engage themselves in food distribution, processing and other parts of the supply chain where ample well-paying employment opportunities will emerge.

Currently, many smallholders lack the means and kind of support to gain from growing food demand. "Initiating and sustaining a process of inclusive transformation requires supporting smallholders' market access by investing in basic infrastructure, creating market incentives, and promoting inclusive agribusiness models. But it is as important to invest in the 'hidden middle' of supply chains where millions of small- and medium-scale enterprises already operate in food processing, storage, logistics and distribution. Getting this right will be essential to lift smallholders from poverty and food insecurity," said Rob Vos director of IFPRI's Markets, Trade and Institutions Division.

Women are already making significant contributions throughout food systems, but these contributions are often not formally recognized, and women often face constraints that prevent them from engaging on equitable terms. Increasing women's decision-making power and control over resources and assets such as credit, land, and training helps empower them to contribute to food systems in ways that benefit both men and women. "Women's empowerment can spur a wide range of improvements that often reverberate throughout households and societies - from agricultural productivity, to household food security and dietary quality, to maternal and child nutrition," said Hazel Malapit, senior research coordinator at IFPRI.

In African south of the Sahara, youth are expected to play a growing role in food systems but their role in driving growth is often misunderstood. Projections show Africa south of the Sahara will add 30 million people to its working age population each year by 2050, and that much of this growth will be in rural areas. "Africa's rural areas will need to play a major role in providing employment opportunities for young people, but focusing on broad-based rural growth to create thriving economic environments for food system business will likely do more to support these growing youth populations than policies narrowly focused on youth," said James Thurlow, senior research fellow at IFPRI.

Political instability and conflict have been fundamental drivers to the recent surge in global hunger numbers, with more than half of all undernourished people living in conflict-affected countries. "Integrating conflict-affected people into food systems - either in their places of origin or the locales to which they have fled - can substantially help them rebuild their lives," said Vos. Providing long-term refugees with access to land and means to build secure livelihoods can support their own food security while also contributing to local economies. Rebuilding local agriculture and food value chains for conflict-affected people will bolster resilience thereby reducing the risk of further conflict and sowing the seeds for last peace.

Across the developing world national food systems are already transforming rapidly, creating challenges and opportunities to make them more inclusive to all these groups. Case studies of these transformations in Bangladesh, Ethiopia, Nigeria, and Viet Nam provide useful examples of the drivers and components of change, as well as the promising entry points for actions that can increase inclusion. "Approaches to food system transformation must be country specific, as each country's food system is unique," said John McDermott, director of the CGIAR Research Program on Agriculture for Nutrition and Health.

Governments can foster these inclusive food systems by enacting laws, policies, and regulations that provide basic infrastructure, create the right market incentives, promote inclusive agribusiness models and leverage the potential of digital technology. Additionally, investments in human capital in areas such as secure land tenure rights, improved access to information, and stronger social protections can lower the barriers to participation that man marginalized groups face.

"The spread of COVID-19 has highlighted how vulnerable we all can be to global shocks," said Swinnen. "Greater inclusivity in food systems is not a panacea for this or any other crisis, but it is a critical part of strengthening our resilience. Times of crises also offer opportunities for change and it is essential that we act now so that everyone, especially the most vulnerable, can recover from the COVID-19 shock and be prepared to withstand future shocks."

The report also features chapters analyzing developments in agri-food systems in Africa south of the Sahara, the Middle East and North Africa, Central Asia, South Asia, East and Southeast Asia, and Latin America and the Caribbean.

Credit: 
International Food Policy Research Institute

Study finds provider capacity to expand abortion -- implications for access during COVID-19

AURORA, Colo. (April 22, 2020) - Researchers at the University of Colorado Anschutz Medical Campus have found that interest in abortion care among advance practice clinicians (APCs) in Colorado is substantial, though barriers must be addressed in order to increase access with APCs (nurse practitioners, nurse midwives, physician's assistants).

The study, out today in Women's Health Issues, surveyed APCs in Colorado on their interest in and ability to provide abortion. Of the 512 participants, 45% say they are interested, or possibly interested in medication abortion training -- the use of oral medications to end a pregnancy up to 10 weeks. Moreover, one-quarter are interested in, or possibly interested in, training for procedural abortions that occur in the clinic up to 12 weeks of pregnancy. "Both types of first-trimester abortions are 13 times safer than carrying a pregnancy to term and delivering, and 90% of abortions in Colorado occur in the first-trimester," said lead author and Associate Professor with University of Colorado College of Nursing Kate Coleman-Minahan, PhD.

Colorado is one of ten states and the District of Columbia that allows APCs to provide abortion care. Only 12% of respondents in the study indicated they knew that they can legally provide abortion services. "Our study included providers in all types of practice, including primary care, urgent/emergency care and specialty care, like orthopedics. Even though most were not aware they can provide, the fact that almost half have some interest in training to provide abortion shows Colorado has the provider capacity to expand abortion access," says Coleman-Minahan.

But training providers might not be enough. Few study participants believed their facility would allow them to provide. Administrative and regulatory barriers, such as the need to physically separate abortion provision from other services receiving certain federal funds, must be addressed.

Recently, state-level abortion ban attempts have picked up steam because of the COVID-19 pandemic. Eleven states are currently restricting or eliminating abortion care due to "non-essential care" designations and stay-at-home orders. Colorado is not one of those states, however. According to Coleman-Minahan, "Colorado has not restricted abortion access during this pandemic. However, training providers won't be helpful unless more facilities allow them to provide abortion care."

Credit: 
University of Colorado Anschutz Medical Campus

Novel research on African bats pilots new ways in sharing and linking published data

image: One of the possibly three new to science bat species, previously referred to as Hipposideros caffer or Sundevall's leaf-nosed bat.

Image: 
B. D. Patterson / Field Museum

Newly published findings about the phylogenetics and systematics of some previously known, but also other yet to be identified species of Old World Leaf-nosed bats, provide the first contribution to a recently launched collection of research articles, whose task is to help scientists from across disciplines to better understand potential hosts and vectors of zoonotic diseases, such as the Coronavirus. Bats and pangolins are among the animals already identified to be particularly potent vehicles of life-threatening viruses, including the infamous SARS-CoV-2.

The article, publicly available in the peer-reviewed scholarly journal ZooKeys, also pilots a new generation of Linked Open Data (LOD) publishing practices, invented and implemented to facilitate ongoing scientific collaborations in times of urgency like those we experience today with the COVID-19 pandemic currently ravaging across over 230 countries around the globe.

In their study, an international team of scientists, led by Dr Bruce Patterson, Field Museum's MacArthur curator of mammals, point to the existence of numerous, yet to be described species of leaf-nosed bats inhabiting the biodiversity hotspots of East Africa and Southeast Asia. In order to expedite future discoveries about the identity, biology and ecology of those bats, they provide key insights into the genetics and relations within their higher groupings, as well as further information about their geographic distribution.

"Leaf-nosed bats carry coronaviruses--not the strain that's affecting humans right now, but this is certainly not the last time a virus will be transmitted from a wild mammal to humans," says Dr Terrence Demos, a post-doctoral researcher in Patterson's lab and a principal author of the paper. "If we have better knowledge of what these bats are, we'll be better prepared if that happens," he adds.

"With COVID-19, we have a virus that's running amok in the human population. It originated in a horseshoe bat in China. There are 25 or 30 species of horseshoe bats in China, and no one can determine which one was involved. We owe it to ourselves to learn more about them and their relatives," comments Patterson.

In order to ensure that scientists from across disciplines, including biologists, but also virologists and epidemiologists, in addition to health and policy officials and decision-makers have the scientific data and evidence at hand, Patterson and his team supplemented their research publication with a particularly valuable appendix table. There, in a conveniently organized table format, everyone can access fundamental raw genetic data about each studied specimen, as well as its precise identification, origin and the natural history collection it is preserved. However, what makes those data particularly useful for researchers looking to make ground-breaking and potentially life-saving discoveries is that all that information is linked to other types of data stored at various databases and repositories contributed by scientists from anywhere in the world.

Furthermore, in this case, those linked and publicly available data or Linked Open Data (LOD) are published in specific code languages, so that they are "understandable" for computers. Thus, when a researcher seeks to access data associated with a particular specimen he/she finds in the table, he/she can immediately access additional data stored at external data repositories by means of a single algorithm. Alternatively, another researcher might want to retrieve all pathogens extracted from tissues from specimens of a specific animal species or from particular populations inhabiting a certain geographical range and so on.

Credit: 
Pensoft Publishers

Growing volume of gun policy research creates basis for policy decisions

Research evaluating the effectiveness of gun policies has surged over the past two years, providing information policymakers and the public need to make sound decisions on policies designed to reduce homicides and injuries while protecting individuals' rights, according to a new RAND Corporation study.

Scientific evidence now supports the conclusion that child-access prevention laws reduce self-inflicted fatal and nonfatal firearm injuries among young people, including accidental injuries and intentional self-injury.

Researchers also conclude there is supportive evidence that stand-your-ground laws are associated with increases in firearm homicides and moderate evidence that they increase the total number of homicides.

"The evidence base for laws involving firearms has increased enough that there is now supportive evidence about the influence of these types of laws on at least some outcomes, including injuries and deaths," said Rosanna Smart, lead author of the new analysis and an economist at RAND, a nonprofit, nonpartisan research organization. "However, there are many factors that policymakers may need to consider when adopting or modifying policy.

"There is is far less robust evidence about effects of gun policies on other outcomes that may be important, such as defensive or recreational gun use and gun ownership."

The findings are from the second edition of a RAND project that evaluated thousands of studies to assess the available evidence about 18 commonly discussed gun policies on a range of outcomes, including injuries and deaths, mass shootings, defensive gun use, and participation in hunting and sport shooting.

The updated version of the project adds five gun policies to the extensive evaluation and includes a first-of-its-kind database of household gun ownership rates across America from 1980 to 2016.

The RAND analysis identified 123 studies that investigated the causal effects of gun polices on any of the targeted outcomes. The previous edition of the project released in 2018 had found 63 studies that met high-quality standards for causal research.

"With few exceptions, there remains a surprisingly limited base of rigorous scientific evidence concerning the effects of many commonly discussed gun policies," said Andrew Morral, leader of the RAND Gun Policy in America project and a senior behavioral scientist. "By highlighting where scientific evidence is accumulating, we hope to build consensus around a shared set of facts through transparent and impartial review."

In the new version of the RAND gun policy project, researchers determined there now is moderate evidence that state laws that impose firearms prohibitions for individuals subject to domestic violence restraining orders decrease firearm-related homicides against intimate partners and total overall homicides.

While federal law establishes such prohibitions, states also should consider adopting the strategy as a way to reduce homicides against intimate partners, according to the analysis. These laws may be most effective when they can be applied to a wide range of domestic violence cases and where the law ensures that information about the cases are included in databases used to conduct background checks.

Researchers also concluded that there is moderate evidence that waiting periods reduce firearm suicides and total homicides. Waiting-period laws may be an effective policy lever for states to consider to reduce gun deaths.

There is limited evidence that laws prohibiting the purchase or possession of guns by individuals with histories of adjudicated mental health or incapacity reduce violence crime. Researchers recommend that states consider requiring a background check investigating all types of adjudicated mental health histories that lead to federal prohibitions on firearm purchase or possession for private gun sales.

The analysis also found limited evidence that licensing and permitting requirements for purchasing a firearm reduce total suicides and firearm suicides among adults, as well as limited evidence that shall-issue or right-to-carry laws increase violent crime rates.

Limited evidence was found that before adoption of a ban on the sale of assault weapons and high-capacity magazines, there is an increase in the sales and prices of the products that the ban will prohibit. Additionally, there is limited evidence that a minimum age of 21 to purchase firearms may reduce suicides among youth.

Only inconclusive evidence was found for the effects of minimum age of possession laws, firearm-surrender laws, extreme risk protection orders or "red-flag" laws, firearm safety training requirements, firearm sales reporting, recording and registration requirements, bans on low-quality handguns, and permit-less carry laws. No studies meeting the RAND standard were found for gun-free zones, allowing armed staff in K-12 schools and requiring the reporting of lost or stolen firearms.

The vast majority of research has evaluated the effects of laws on gun violence outcomes, such as suicide and homicide, with far less evidence to inform effects on defensive or recreational gun use. In part, the absence of research on these outcomes reflects an absence of reliable and systematic data collection.

The RAND study urges the federal government to make a sustained commitment to fund gun research on an ongoing basis. Sustained large-scale investments are necessary to develop a data infrastructure to measure outcomes such as gun crimes, nonfatal gun injury and gun ownership.

But researchers warn that until that happens, advances in knowledge about gun policies will need to be supported by private foundations.

"While there are promising signs that more high-quality studies are being performed about gun policies, there still needs to be sustained federal support for this work at levels similar to what is spent on comparable public safety threats such as highway safety and the opioid crisis," Morral said.

To make progress toward providing improved data to support gun policy research, the new RAND gun ownership database combines information from a wide range of survey and administrative data sources. It provides estimates of the proportion of individuals living in households with a firearm for every state in each year from 1980 to 2016. The database generally shows that household gun ownership has declined over the period.

The tool should allow other researchers to use the annual state-level measures of household firearm ownership to test theories about firearm ownership and usage, including their relation to crime or public policy.

The United States has the highest gun ownership rate in the world, with estimates suggesting that Americans own as many as 300 million guns. Between 10 million and 20 million Americans actively participate in hunting or sport shooting annually, and the gun industry generates $16 billion in revenue and employs hundreds of thousands in gun manufacturing, distribution, sales and recreation.

At the same time, more than 39,000 people die each year from deliberate and unintentional gun injuries, with two-thirds of these deaths being suicides. Despite wide acknowledgement that gun violence levels are too high, states have pursued diverse approaches to regulating firearms that reflect little consensus on how best to prevent firearm violence while preserving the right to own firearms.

Support for the RAND Gun Policy in American project was provided by Arnold Ventures.

The report, "The Science of Gun Policy: A Critical Synthesis of Research Evidence on the Effects of Gun Policies in the United States," [Second Edition] is available at http://www.rand.org.

Other authors of the project are Sierra Smucker, Samantha Cherney, Terry L. Schell, Samuel Peterson, Sangeeta C. Ahluwalia, Matthew Cefalu, Lea Xenakis, Rajeev Ramchand and Carole Roan Gresenz, Samuel Peterson, Brian Garrett Vegetabile and Adam Scherling.

Credit: 
RAND Corporation

Microwaves power new technology for batteries, energy

image: This image shows disodium terephthalate flowers produced from polyethylene terephthalate via microwave processing in two minutes. Purdue University researchers created a technique to turn waste polyethylene terephthalate, one of the most recyclable polymers, into components of batteries.

Image: 
Vilas Pol/Purdue University

WEST LAFAYETTE, Ind. - New battery technology involving microwaves may provide an avenue for renewable energy conversion and storage.

Purdue University researchers created a technique to turn waste polyethylene terephthalate, one of the most recyclable polymers, into components of batteries.

"We use an ultrafast microwave irradiation process to turn PET, or polyethylene terephthalate, flakes into disodium terephthalate, and use that as battery anode material," said Vilas Pol, a Purdue associate professor of chemical engineering who has worked with the Purdue Research Foundation Office of Technology Commercialization to develop several battery technologies. "We are helping to address the growth in the proliferation of renewable energy conversion and storage, which stems from the societal attention and increasing awareness of climate change and energy resource limitation."

The Purdue team tried the approach with both lithium-ion and sodium-ion battery cells. They worked with researchers from the Indian Institute of Technology and Tufts University. The battery technology is presented in the journal ACS Sustainable Chemistry & Engineering.

Pol said that while lithium-ion technology is currently dominating both the portable electronics and electric vehicles market, sodium-ion battery research also has gained significant attention due to its low cost and appealing electrochemical performance in grid applications.

"The applicability of the microwave technique on organic reactions has gained attention in recent times due to its advantage of the rapid reaction process," Pol said. "We have accomplished the complete conversion of PET to disodium terephthalate within 120 seconds, in a typical household microwave setup."

Pol said the materials used in the Purdue technology are low-cost, sustainable and recyclable.

Credit: 
Purdue University

UK coronavirus policy places people aged 60-69 at increased risk

The 7.3 million people in the UK aged between 60 and 69 are at increased risk of severe illness and death from COVID-19. Although the government's age threshold for isolation is 70 years and over, data from countries such as China and Italy show that people aged 60-69 years are also at high risk of complications and death from COVID-19.

Writing in the Journal of the Royal Society of Medicine, Professor Azeem Majeed, Head of the Department of Primary Care & Public Health at Imperial College London, said that while this group is at a lower risk of severe illness when compared to those aged 70 years or older, their risk is still considerable.

Case fatality rates for those aged 60-69 are 3.5% in Italy and 3.6% in China. Other countries, including Switzerland and France, encourage those aged 65 and older to enforce strict public health measures due to their increased risk of severe illness and death from COVID-19.

Prof Majeed, who co-authored the paper with colleagues from Imperial College London and the University of Exeter, said: "The UK's policy is at variance with the World Health Organisation, which states that those above the age of 60 years are at the highest risk, requiring additional preventative measures."

"National and global spread of COVID-19 is accelerating. To reduce hospitalisations, intensive care admissions and death we recommend that those aged between 60 and 69 are particularly stringent when implementing public health measures such as social distancing and personal hygiene."

The authors conclude: "In the absence of government guidance, people in this group can make their own informed decisions on how to minimise their risks of COVID-19 infection. This can include isolating themselves in a similar manner to that recommended by the UK government for people aged 70 years and over."

Credit: 
SAGE

Researchers develop new microneedle array combination vaccine delivery system

image: Microneedle Array Vaccine: The vaccine is delivered into the skin through a fingertip-sized patch of microscopic needles.

Image: 
UPMC

Philadelphia, April 21, 2020 - In parallel to their current work on a potential coronavirus vaccine, researchers at the University of Pittsburgh School of Medicine have developed a new vaccine delivery system for vaccines using live or attenuated viral vectors: a finger-tip sized patch that contains 400 tiny needles, each just half of one millimeter. Their progress is reported in the Journal of Investigative Dermatology, published by Elsevier.

The needles, made from sugar and the specific cargo being delivered, comprise a three-dimensional (3D), multicomponent dissolving microneedle array (MNA). While feeling like having Velcro pressed against the skin, the vaccine would penetrate the upper level of the skin, absorb moisture from the skin, and then dissolve and release molecules that prompt the immune system to make antibodies to attack the virus. In addition to antibody production, this technology has the potential to improve cellular immune responses in patients and expand global immunization capabilities. It is clear evidence of the broad reach and contribution of skin scientists, even extending into pandemic vaccine design.

Explaining the importance of this work, lead author Louis D. Falo, Jr., MD, PhD, Professor and Chairman of the Department of Dermatology, University of Pittsburgh School of Medicine and UPMC, Pittsburgh, PA, USA, explains, "We are developing this new delivery technology because while traditional vaccines are often effective in inducing antibody responses, they frequently fail to generate the cellular responses that are essential to prevent or treat many cancers or infectious diseases."

The skin is an ideal vaccination site because it contains an immune network that is highly responsive and encourages the generation of strong and long-lasting immunity.

Dissolvable MNAs are designed to mechanically penetrate the superficial cutaneous layers, rapidly dissolve upon insertion into the skin, and deliver uniform quantities of biocargo to a defined 3D space within the skin. This enables localized delivery of low amounts of drugs or vaccines to achieve high concentrations in this specific skin microenvironment.

Using in vivo mouse models, investigators generated the 3D multicomponent dissolvable vaccine platform combining a live adenovirus-encoded antigen with an added component, polyinosinic:polycytidylic acid (poly I:C), an immunostimulant used to simulate the skin immune system. This successfully induced both antibody responses and stronger cellular immune responses.

Induction of antigen-specific cellular immunity is a point of emphasis in the vaccine field, as evidenced by recent efforts to generate "universal vaccines" for mutable infectious diseases like influenza, HIV, and coronaviruses by targeting infected cells.

"Remarkably," says Dr. Falo, "the MNA vaccine platforms incorporating both antigen-encoding adenovirus and poly I:C augmented the destruction of targeted cells significantly compared to MNA-delivery of the same adenovirus alone." The researchers also found that the MNAs integrating both poly I:C and adenovirus retained their immunogenicity after one month of storage at 4? C. MNA-delivered vaccines also have advantages in their ease of fabrication, application, and storage compared to other vaccine delivery platforms.

"Our results suggest that multicomponent MNA vaccine platforms uniquely enable delivery of both adjuvant and antigen-encoding viral vectors to the same skin microenvironment, resulting in improved immunogenicity including cellular immune responses," comments Dr. Falo. "This MNA delivery approach could improve the effectiveness of adenoviral vaccines now in development for the prevention of coronavirus disease (COVID-19)."

Credit: 
Elsevier

Computer scientists create a 'laboratory' to improve streaming video

In these days of social distancing, as millions cloister at home to binge-watch TV over the internet, Stanford researchers have unveiled an algorithm that demonstrates a significant improvement in streaming video technology.

This new algorithm, called Fugu, was developed with the help of volunteer viewers who watched a stream of video, served up by computer scientists who used machine learning to scrutinize this data flow in real time, looking for ways to reduce glitches and stalls.

In a scientific paper, the researchers describe how they created an algorithm that pushes out only as much data as the viewer's internet connection can receive without degrading quality.

"In streaming, avoiding stalls depends heavily on these algorithms," says Francis Yan, a doctoral candidate in computer science and first author of the paper, which received the 2020 USENIX NSDI Community Award.

Many of the prevailing systems for streaming video are based on something called the Buffer-Based Algorithm, known as BBA, which was developed seven years ago by then-Stanford graduate student Te-Yuan Huang, along with professors Nick McKeown and Ramesh Johari.

BBA simply asks the viewer's device how much video it has in its buffer. For example, if it has less than 5 seconds stored, the algorithm sends lower quality footage to guard against interruptions. If the buffer has more than 15 seconds stored, the algorithm sends the highest quality video possible. If the number falls in between, the algorithm adjusts the quality accordingly.

Although BBA and similar algorithms are widespread in the industry, there have been repeated attempts by researchers over the years to develop more sophisticated algorithms using machine learning -- a form of artificial intelligence in which computers teach themselves to optimize some process.

But in a modern variation of the old garbage-in-garbage-out computer adage, these machine learning algorithms generally require simulated data to learn from, rather than the real thing delivered over the real internet. Therein lies a problem.

"The internet turns out to be a much messier place than our simulations can model," said Keith Winstein, an assistant professor of computer science who supervised the project and advised Yan along with associate professor of computer science and electrical engineering Philip Levis. "What Francis found is that there can be a gulf between making one of these algorithms work in simulation versus making it work on the real internet."

To create a realistic microcosm of the TV-viewing world, Winstein's team erected an antenna atop Stanford's Packard Building to pull in free, over-the-air broadcast signals which they then compressed and streamed to volunteers who signed up to participate in the research project, known as Puffer.

Starting in late 2018, the volunteers streamed and watched TV programs via Puffer and the computer scientists simultaneously monitored the data stream using their own machine learning algorithm, Fugu, and four other leading contenders, including BBA, that were trained to adjust their performance based on the actual quality conditions the viewers were experiencing.

At the start of their stream, each viewer was randomly assigned one of the five streaming algorithms and the Stanford team recorded streaming data like the average video quality, the number of stalls and the length of time the viewer tuned in.

The results disagreed with some earlier research studies that had been based on simulations or on smaller tests. When the supposedly sophisticated machine learning algorithms were tested against BBA in the real world, the simpler standard held its own. By the end of the trial, however, Fugu had outperformed the other algorithms -- including BBA -- in terms of least interruption time, highest image resolution and the consistency of video quality. What's more, those improvements appear to have the power to keep viewers tuned in. Viewers watching Fugu-fed video streams lingered an average of 5-9% longer than other tested algorithms.

"We've found some surprising ways in which the real world differs from simulation, and how machine learning can sometimes produce misleading results. That's exciting in that it suggests a lot of interesting challenges to be solved," Winstein says.

Credit: 
Stanford University School of Engineering

How SARS-CoV-2 gets into respiratory tissue -- and how it may exploit one of our defenses

What makes SARS-CoV-2, the virus behind COVID-19, such a threat? A new study, led by Jose Ordovas-Montanes, PhD at Boston Children's Hospital and Alex K. Shalek, PhD at MIT, pinpoints the likely cell types the virus infects. Unexpectedly, it also shows that one of the body's main defenses against viral infections may actually help the virus infect those very cells. Findings were published April 21 by the journal Cell.

The peer-reviewed study, published as a preprint, will help focus efforts to understand what SARS-COV-2 does in the body, why some people are more susceptible, and how best to search for treatments, the researchers say.

Multiple research models

When news broke about a new coronavirus in China, Ordovas-Montanes and Shalek had already been studying different cell types from throughout the human respiratory system and intestine. They also had gathered data from primates and mice.

In February, they began diving into these data.

"We started to look at cells from tissues such as the lining of the nasal cavity, the lungs, and gut, based on reported symptoms and where the virus has been detected," says Ordovas-Montanes. "We wanted to provide the best information possible across our entire spectrum of research models."

COVID-19-susceptible cells

Recent research had found that SARS-CoV-2 -- like the closely related SARS-CoV that caused the SARS pandemic, uses a receptor called ACE2 to gain entry into human cells, aided by an enzyme called TMPRSS2. That led Ordovas-Montanes and Shalek and colleagues to ask a simple question: Which cells in respiratory and intestinal tissue express both ACE2 and TMPRSS2?

To address this question, the team turned to single-cell RNA sequencing, which identifies which of roughly 20,000 genes are "on" in individual cells. They found that only a tiny percentage of human respiratory and intestinal cells, often well below 10 percent, make both ACE2 and TMPRSS2. Those cells fall in three types: goblet cells in the nose that secrete mucus; lung cells known as type II pneumocytes that help maintain the alveoli (the sacs where oxygen is taken in); and one type of so-called enterocytes that line the small intestine and are involved in nutrient absorption.

Sampling from non-human primates showed a similar pattern of susceptible cells.

"Many existing respiratory cell lines may not contain the full mix of cell types, and may miss the types that are relevant," Ordovas-Montanes notes. "Once you understand which cells are infected, you can start to ask, 'How do these cells work?' 'Is there anything within these cells that is critical for the virus's life cycle?' With more refined cellular models, we can perform better screens to find what existing drugs target that biology, providing a stepping stone to go into mice or non-human primates."

Interferon: Helpful or harmful?

But it was the study's second finding that most intrigues the scientists. They discovered that the ACE2 gene, which encodes the receptor used by SARS-CoV-2 to enter human cells, is stimulated by interferon -- one of the body's main defenses when it detects a virus. Interferon actually turned the ACE2 gene on at higher levels, potentially giving the virus new portals to get in.

"ACE2 is also critical in protecting people during various types of lung injury," notes Ordovas-Montanes. "When ACE2 comes up, that's usually a productive response. But since the virus uses ACE2 as a target, we speculate that it might be exploiting that normal protective response."

Interferons, in fact, are being tested as a treatment for COVID-19. Would they help, or would they do more harm than good? That's not yet clear.

"It might be that in some patients, because of the timing or the dose, interferon can contain the virus, while in others, interferon promotes more infection," says Ordovas-Montanes. "We want to better understand where the balance lies, and how we can maintain a productive antiviral response without producing more target cells for the virus to infect."

ACE inhibitors and cytokine storms

The findings may also raise new lines of inquiry around ACE inhibitors. These drugs are commonly used to treat hypertension, which has been linked to more severe COVID-19 disease. Are ACE inhibitors affecting people's risk?

"ACE and ACE2 work in the same pathway, but they actually have different biochemical properties," Ordovas-Montanes cautions. "It's complex biology, but it will be important to understand the impact of ACE inhibitors on people's physiological response to the virus."

It's also too soon to try to relate the study findings to the "cytokine storm," a runaway inflammatory response that has been reported in very sick COVID-19 patients. Cytokines are a family of chemicals that rally the body's immune responses to fight infections, and interferon is part of the family.

"It might be that we're seeing a cytokine storm because of a failure of interferon to restrict the virus to begin with, so the lungs start calling for more help. That's exactly what we're trying to understand right now."

Future directions

The team also wants to explore what the virus is doing in the cells it targets, and to study tissue samples from children and adults to understand why COVID-19 is typically less severe in younger people. Studies will continue at Boston Children's with the support of Benjamin Raby, MD, MPH, chief of pulmonary medicine, Bruce Horwitz, MD, PhD, in emergency medicine, and Scott Snapper, MD, PhD, chief of gastroenterology.

Carly Ziegler, Samuel Allon, and Sarah Nyquist, of MIT and Harvard, and Ian Mbano of the Africa Health Research Institute were co-first authors on the paper in Cell. The study was done in collaboration with the Human Cell Atlas (HCA) Lung Biological Network group. The authors report no competing interests. See the paper for a full list of funders and authors.

"This has been an incredible community effort -- not just within Boston, but also with collaborators around the world who have all shared their unpublished data to try and make potentially relevant information available as rapidly as possible," says Shalek, who was co-senior author on the paper with Ordovas-Montanes. "It's inspiring to see how much can be accomplished when everyone comes together to tackle a problem."

Credit: 
Boston Children's Hospital

Easing the burden of coronavirus with virtual reality

image: Explores the psychological and social issues surrounding the Internet and interactive technologies.

Image: 
Mary Ann Liebert Inc., publishers

New Rochelle, NY, April 21, 2020--A new article discusses the psychological stresses imposed by the coronavirus pandemic and suggests that virtual reality can help alleviate the psychological impact of the need for social isolation. The article, which provides a link to a free 3-dimensional 360 video and suggestions for how to use it, is published in Cyberpsychology, Behavior, and Social Networking, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. Click here to read the full-text article free on the Cyberpsychology, Behavior, and Social Networking website.

Giuseppe Riva, PhD, IRCCS Istituto Auxologico Italiano and Università Cattolica del Sacro Cuore (Milan, Italy), and Journal Editor-in-Chief Brenda Wiederhold, PhD, Virtual Reality Medical Center (La Jolla, CA) and Virtual Reality Medical Institute (Brussels, Belgium), coauthored the article entitled "How Cyberpsychology and Virtual Reality Can Help Us to Overcome the Psychological Burden of Coronavirus."

The coronavirus pandemic is forcing people to manage three different psychological problems at the same time: the stress of the disease, the disappearance of places, and the crisis of the sense of community. The fear of getting sick is making us anxious and the need to quarantine is making us lose our sense of place and community. Virtual reality simulates reality. The cost of virtual reality technology has come down considerably in recent years. Now there is free access to the specialized 360-degree immersive videos that allow a person to feel like they are actually in a virtual space. The article provides a day-by-day suggested plan for how to use the free 360 video.

"As our society continues to face these difficult times, it becomes imperative to address mental well-being. It is uplifting to see practical uses of advanced technologies, such as Virtual Reality, making a positive impact. Although previously characterized by some as isolating, we see this new use of shared virtual spaces becoming increasingly important as a means to bring individuals and families together. We look forward to continued exploration of ways that can enrich our shared human experience," says Editor-in-Chief Brenda K. Wiederhold, PhD, MBA, BCB, BCN, Interactive Media Institute, San Diego, California and Virtual Reality Medical Institute, Brussels, Belgium.

Credit: 
Mary Ann Liebert, Inc./Genetic Engineering News

ASU scientists lead study of galaxy's 'water worlds'

image: In a diamond-anvil cell, two gem quality single crystal diamonds are shaped into anvils (flat top in the photo) and then faced with each other. Samples are loaded between the culets (flat surfaces), then the sample is compressed between the anvils.

Image: 
Dan Shim/ASU

Astrophysical observations have shown that Neptune-like water-rich exoplanets
are common in our galaxy. These "water worlds" are believed to be covered with a thick layer of water, hundreds to thousands of miles deep, above a rocky mantle.

While water-rich exoplanets are common, their composition is very different from Earth, so there are many unknowns in terms of these planets' structure, composition and geochemical cycles.

In seeking to learn more about these planets, an international team of researchers, led by Arizona State University, has provided one of the first mineralogy lab studies for water-rich exoplanets. The results of their study have been recently published in the journal Proceedings of the National Academy of Sciences.

"Studying the chemical reactions and processes is an essential step toward developing an understanding of these common planet types," said co-author Dan Shim, of ASU's School of Earth and Space Exploration.

The general scientific conjecture is that water and rock form separate layers in the interiors of water worlds. Because water is lighter, underneath the water layer in water-rich planets, there should be a rocky layer. However, the extreme pressure and temperature at the boundary between water and rocky layers could fundamentally change the behaviors of these materials.

To simulate this high pressure and temperature in the lab, lead author and research scientist Carole Nisr conducted experiments at Shim's Lab for Earth and Planetary Materials at ASU using high pressure diamond-anvil cells.

For their experiment, the team immersed silica in water, compressed the sample between diamonds to a very high pressure, then heated the sample with laser beams to over a few thousand degrees Fahrenheit.

The team also conducted laser heating at the Argonne National Laboratory in Illinois. To monitor the reaction between silica and water, X-ray measurements were taken while the laser heated the sample at high pressures.

What they found was an unexpected new solid phase with silicon, hydrogen and oxygen all together.

"Originally, it was thought that water and rock layers in water-rich planets were well-separated," Nisr said. "But we discovered through our experiments a previously unknown reaction between water and silica and stability of a solid phase roughly in an intermediate composition. The distinction between water and rock appeared to be surprisingly 'fuzzy' at high pressure and high temperature."

The researchers hope that these findings will advance our knowledge on the structure and composition of water-rich planets and their geochemical cycles.

"Our study has important implications and raises new questions for the chemical composition and structure of the interiors of water-rich exoplanets," Nisr said. "The geochemical cycle for water-rich planets could be very different from that of the rocky planets, such as Earth."

Credit: 
Arizona State University