More evidence of causal link between air pollution and early death

Study of more than 68 million older Americans using state-of-the-art analyses suggests that US air pollution standards are not protective enough

HARVARD T.H. CHAN SCHOOL OF PUBLIC HEALTH

 

Boston, MA - Strengthening U.S. air quality standards for fine particulate pollution to be in compliance with current World Health Association (WHO) guidelines could save more than 140,000 lives over the course of a decade, according to a new study from Harvard T.H. Chan School of Public Health.

The study, published June 26, 2020 in Sciences Advances, provides the most comprehensive evidence to date of the causal link between long-term exposure to fine particulate (PM2.5) air pollution and premature death, according to the authors.

"Our new study included the largest-ever dataset of older Americans and used multiple analytical methods, including statistical methods for causal inference, to show that current U.S. standards for PM2.5 concentrations are not protective enough and should be lowered to ensure that vulnerable populations, such as the elderly, are safe," said doctoral student Xiao Wu, a co-author of the study.

The new research builds on a 2017 study that showed that long-term exposure to PM2.5 pollution and ozone, even at levels below current U.S. air quality standards, increases the risk of premature death among the elderly in the U.S.

For the new study, researchers looked at 16 years' worth of data from 68.5 million Medicare enrollees--97% of Americans over the age of 65--adjusting for factors such as body mass index, smoking, ethnicity, income, and education. They matched participants' zip codes with air pollution data gathered from locations across the U.S. In estimating daily levels of PM2.5 air pollution for each zip code, the researchers also took into account satellite data, land-use information, weather variables, and other factors. They used two traditional statistical approaches as well as three state-of-the-art approaches aimed at teasing out cause and effect.

Results were consistent across all five different types of analyses, offering what authors called "the most robust and reproducible evidence to date" on the causal link between exposure to PM2.5 and mortality among Medicare enrollees--even at levels below the current U.S. air quality standard of 12 μg/m3 (12 micrograms per cubic meter) per year.

The authors found that an annual decrease of 10 μg/m3 in PM2.5 pollution would lead to a 6%-7% decrease in mortality risk. Based on that finding, they estimated that if the U.S. lowered its annual PM2.5 standard to 10 μg/m3--the WHO annual guideline--143,257 lives would be saved in one decade.

The authors included additional analyses focused on causation, which address criticisms that traditional analytical methods are not sufficient to inform revisions of national air quality standards. The new analyses enabled the researchers, in effect, to mimic a randomized study--considered the gold standard in assessing causality--thereby strengthening the finding of a link between air pollution and early death.

"The Environmental Protection Agency has proposed retaining current national air quality standards. But, as our new analysis shows, the current standards aren't protective enough, and strengthening them could save thousands of lives. With the public comment period for the EPA proposal ending on June 29, we hope our results can inform policymakers' decisions about potentially updating the standards," said co-author Francesca Dominici, Clarence James Gamble Professor of Biostatistics, Population, and Data Science.

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Other Harvard Chan School co-authors of the study included research scientist Danielle Braun and Joel Schwartz, professor of environmental epidemiology.

Funding for the study came from NIH grants R01 ES024332-01A1, P50 MD010428, R21 ES024012, R01 ES026217, R01 ES028033, MD012769, R01 ES030616, and P30 ES09089; HEI grant 4953-RFA14-3/16-4; and USEPA grants 83587201-0 and RD-83479801.

"Evaluating the Impact of Long-term Exposure to Fine Particulate Matter on Mortality Among the Elderly," Xiao Wu, Danielle Braun, Marianthi-Anna Kioumourtzoglou, Francesca Dominici, Science Advances, June 26, 2020, doi: 10.1126/sciadv.aba5692.

Visit the Harvard Chan School website for the latest news, press releases, and multimedia offerings.

Harvard T.H. Chan School of Public Health brings together dedicated experts from many disciplines to educate new generations of global health leaders and produce powerful ideas that improve the lives and health of people everywhere. As a community of leading scientists, educators, and students, we work together to take innovative ideas from the laboratory to people's lives--not only making scientific breakthroughs, but also working to change individual behaviors, public policies, and health care practices. Each year, more than 400 faculty members at Harvard Chan School teach 1,000-plus full-time students from around the world and train thousands more through online and executive education courses. Founded in 1913 as the Harvard-MIT School of Health Officers, the School is recognized as America's oldest professional training program in public health.

Report points to intergroup tensions from different interpretations of social distancing

UNIVERSITY OF BATH

 

Changes to lockdown measures in the UK and around the world in an effort to restart the economy could lead to wide disparity in how the public adheres to social distancing, according to a new report from psychologists at the University of Bath.

In a paper published in the British Journal of Social Psychology, the researchers warn of emerging tensions that will arise between groups who interpret messages about social distancing in different ways and the challenge this poses to policymakers.

They suggest that in March, strict lockdown guidelines supported by legal and policy changes, meant that most people adhered to the same mitigating practices including isolation and distancing.

Now that lockdown is easing in many parts of the world, with policies becoming more ambiguous, many practices now need to be negotiated on an interpersonal level, they argue. This means that ensuring compliance will increasingly rely on informal, social policing between individuals: both for those who do, versus those who do not uphold social distancing.

Over recent weeks in the UK, scenes of packed sunny beaches have filled newspapers, leading some to question the sense of others, labelled 'covidiots'. For the researchers this is a sign of mixed messaging surrounding the relaxation of lockdown with different interpretations by individuals.

They warn that morally blaming individuals for the impact of their behaviour on the pandemic - as evidenced in the recent threat to close beaches - may detract from a much-needed discussion over whether guidelines are fit for purpose and their effect on infection rates.

Equally, they draw attention to moral challenges faced by others who wish to maintain strict distancing or isolation and the challenges they now face under pressure to socialise without wanting to appear rude or overdramatic. The researchers suggest that how individuals continue to differently interpret public health messages about COVID-19 will lead to increased tensions between groups moving further into summer.

Lead researcher Annayah Prosser from the Department of Psychology at the University of Bath explains: "Strict lockdown guidelines meant that until recently everyone was adhering to the same mitigating practices such as isolation and distancing. However, now that lockdown is easing, and policy is becoming more ambiguous, many practices now need to be negotiated on an interpersonal level. For example, at the height of lockdown you didn't need to decline an invitation to a social gathering, because it was technically against the law. Now, if you decline an invitation, you could be perceived as rude, or as a 'do-gooder' who thinks they're better than everyone else."

In their report, the team outline how this person-to-person informal regulation poses difficulties for people who want to continue to maintain strict practices over time, who may increasingly face social derogation and ostracism from others who behave differently.

Annayah Prosser added: "Our main recommendation for individuals is to avoid portraying others as morally 'good' or 'bad' for their actions. People may have complex reasons for their behaviour, that may not be visible on sight or through a short social media post. These choices are tough and simplifying behaviour as 'good' or 'bad' without knowing the full story could lead to increased tensions and polarisation at a time when communities need to work together constructively to address the crisis."

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Spraying ethanol to nanofiber masks makes them reusable

POHANG UNIVERSITY OF SCIENCE & TECHNOLOGY (POSTECH)

IMAGE: EVALUATION OF BREATHING COMFORT BY INFRARED THERMAL CAMERA: (A) AIR AND MOISTURE TRANSMISSION AND (B) CO2 TRANSMISSION view more 

CREDIT: HYUNG JOON CHA (POSTECH)

As the COVID-19 pandemic spreads around the world, masks have become an essential personal hygiene product as the first line of defense to protect one's respiratory system against the viruses and germs that spread through droplets in the air. It's a waste to dispose the masks after single use but troubling to reuse them. In light of this, a Korea-Japan research team recently released findings that compare and analyze the performance and functional differences of the filters used in masks after they are cleaned with ethanol.

Professor Hyung Joon Cha and doctoral candidates Jaeyun Lee and Yeonsu Jeong of the Department of Chemical Engineering at POSTECH and Professor Ick-Soo Kim and doctoral candidates Sana Ullah and Azeem Ullah of Shinshu University in Japan have been jointly analyzing the filtration efficiency, airflow rate, surface and morphological properties of the mask filters after they undergo cleaning treatments.

The research team verified the results using two types of cleaning procedures: First one was spraying 75% ethanol on the mask filter then air drying it, second was to saturate the filter in a 75% ethanol solution then air drying it.

A study of the melt-blown filters commonly used in N95 masks and the nanofiber filters produced by electrospinning found that just by spraying ethanol three or more times on the two materials or dipping them in the ethanol solution for more than five minutes effectively inhibit pathogens that can remain inside the mask filter.

The filtration efficiency of both materials in its first usage was measured at 95% and above, indicating that the wearer's respiratory system is effectively protected. It was also confirmed that surface of both materials do not allow water to adhere well, sufficiently hindering wetting by moisture or saliva (droplets).

However, the filtration efficiency of the melt-blown filter decreased by up to 64% when cleaned with ethanol solution and reused. On the other hand, the filtration efficiency of nanofiber filters when reused 10 times through ethanol spray cleaning or immersion in ethanol solution for 24 hours maintained nearly consistent high filtration efficiency.

Schematic diagram on spraying and dipping treatments of face mask filters using 75% ethanol for evaluation of reusability

The joint research team attributed this difference to the decrease in static electricity in the filters after cleaning. Melt-blown filters rely in part on the electrostatic effect of the surface when filtering particles. However, nanofiber does not rely on static electricity but filters according to the morphological properties and pore size of the surface, and is not deformed by ethanol.

Moreover, nanofiber filters have better breathability because they have much higher heat and carbon dioxide emission capabilities compared to the melt-blown filters. Biosafety tests using human skin and vascular cells also confirmed no cytotoxicity.

In summary, both mask filters have similar filtration performance in its initial use, but only nanofiber filters can be reused multiple times through a simple ethanol cleaning process.

POSTECH Professor Hyung Joon Cha explained the significance of the research by commenting, "This research is an experiment that has verified the biosafety of nanofiber masks - which have recently become a hot issue - and their ability to maintain filtration efficiency after cleaning."

In addition, Professor Ick-Soo Kim of Shinshu University added, "I hope the nanofiber masks will help everyone as a means of preventing contagion in the possible second or third wave of COVID-19.

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These research findings were recently published online in the international journal ACS Applied Nano Materials published by the American Chemical Society.

Ladder falls have long-lasting consequences for older blokes

UNIVERSITY OF QUEENSLAND

IT only takes a moment to fall off a ladder, but the psychological impacts are long-lasting, particularly for older males.

In the world's first study of long-term impacts from ladder falls, Queensland researchers have found half of fallers experience a deterioration in their psychological wellbeing for at least six months after the incident.

The University of Queensland's Dr Rob Eley said those who fell experienced sleeping problems, anxiety, depression and pain well after checking out of hospital.

"Ladder falls go far beyond that of the physical injury; they significantly impact a person's mental health and the whole family," Dr Eley said.

"It's frustrating because ladder-related falls are frequently preventable, yet they're a common cause of injuries presented at the emergency department.

"Our study found males over 55 years old are particularly at risk, making up more than half of all our ladder-related fall cases."

The researchers followed 134 Queenslanders who presented to emergency at Princess Alexandra and Nambour General Hospitals between October 2015 and October 2016 as a result of a fall from a ladder.

The team used the Assessment of Quality of Life (AQoL) scale to measure the subjects' physical and psychological recovery over time.

The patients spent an average of five days in hospital with the most common injuries including spinal fractures, rib fractures, tibia or fibula fractures, radius or ulna fractures, pelvic fractures, and traumatic pneumothorax.

The study found that most injuries occurred in non-occupational settings during home maintenance.

Of those who were employed at the time, 80 per cent required at least four weeks off work, and 16 per cent were unable to return or perform their normal function after six months.

Dr Eley said the study highlighted the need for improved safety designs and injury prevention strategies.

"Our research reinforces the need for mandated safety instructions for ladders, as well as safety features like rubber feet, hooks, extender arms, fasteners and stabilisers," Dr Eley said.

"We suggest that at the place of purchase, older men are targeted to reinforce safety instructions, and perhaps are provided with mandatory stabilising features.

"The community also needs to do more to educate people that it's OK to request help or employ home service contractors to complete tasks around the home that require a ladder.

"Ladder falls are frequently preventable and our findings demonstrate the need for preventative measures to be taken."

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This study was conducted with Queensland University of Technology and Queensland Health, funded by the Emergency Medicine Foundation, and is published in the journal, PLOS ONE. DOI: 10.1371/journal.pone.0235092.

IMAGE: AN ANIMATION DEPICTING SPECIFIC GENOMIC VARIANTS THAT CAUSE A DISEASE CALLED FAMILIAL MEDITERRANEAN FEVER (FMF) MAY ALSO CONFER INCREASED RESILIENCE TO THE PLAGUE. view more 

CREDIT: CREDIT: ERNESTO DEL AGUILA III, NHGRI.

Ancient disease may increase resilience to bubonic plague

Genomic variants that cause common periodic fever have spread in Mediterranean populations over centuries, potentially protecting people from the plague

NIH/NATIONAL HUMAN GENOME RESEARCH INSTITUTE

 

Researchers have discovered that Mediterranean populations may be more susceptible to an autoinflammatory disease because of evolutionary pressure to survive the bubonic plague. The study, carried out by scientists at the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health, determined that specific genomic variants that cause a disease called familial Mediterranean fever (FMF) may also confer increased resilience to the plague.

The researchers suggest that because of this potential advantage, FMF-causing genomic variants have been positively selected for in Mediterranean populations over centuries. The findings were published in the journal Nature Immunology.

Over centuries, a biological arms race has been fought between humans and microbial pathogens. This evolutionary battle is between the human immune system and microorganisms trying to invade our bodies. Microbes affect the human genome in many ways. For example, they can influence some of the genomic variation that accumulates in human populations over time.

"In this era of a new pandemic, understanding the interplay between microbes and humans is ever critical," said Dr. Dan Kastner, NHGRI scientific director and a co-author on the paper. "We can witness evolution playing out before our very eyes."

One such microbe is Yersinia pestis, the bacterial agent responsible for a series of well-documented bubonic plague epidemics that led to over 50 million deaths.

FMF, like the plague, is an ancient disease. It is the most common periodic fever syndrome, and symptoms of FMF include recurrent fevers, arthritis, rashes and inflammation of the tissues that line the heart, lungs, and abdominal organs. FMF may also lead to renal failure and death without treatment. The disease appears across the Mediterranean region and mostly affects Turkish, Jewish, Armenian and Arab populations.

Genomic variants in the MEFV gene cause FMF. MEFV encodes a protein called pyrin. In healthy people, pyrin plays a role in the inflammatory response of the body. Pyrin is activated when there is an immune response (for example, in the event of an infection). Pyrin increases inflammation and the production of inflammation-related molecules.

In contrast, FMF patients produce abnormal pyrin because of genomic variants (mutations) in the MEFV gene. Mutated pyrin does not need an infection or other immune trigger to be activated; rather, it is able to directly predispose people to seemingly unprovoked episodes of fever and inflammation.

The MEFV mutations also have other usual properties. Researchers have discovered that people with only one copy of a MEFV genomic variant that causes FMF do not get the disease. Also, prior to effective treatment, those with two copies have a high mortality rate by the age of 40 but usually live long enough to have children.

Despite the lower survival rate, almost 10% of Turks, Jews, Arabs and Armenians carry at least one copy of an FMF-causing genomic variant. If chance were the only factor, that percentage would be much lower.

The researchers proposed that this higher percentage was a consequence of positive natural selection, which is an evolutionary process that drives an increase in specific genomic variants and traits that are advantageous in some way.

"Just like sickle cell trait is positively selected for because it protects against malaria, we speculated that the mutant pyrin in FMF might be helping the Mediterranean population in some way," said Jae Jin Chae, Ph.D., senior author of the paper and a staff scientist in NHGRI's Metabolic, Cardiovascular and Inflammatory Disease Genomics Branch. "The mutant pyrin may be protecting them from some fatal infection."

The team turned to Yersinia pestis, the infamous bubonic plague-causing bacterium, as a possible candidate for driving the evolutionary selection for FMF mutations in the Mediterranean population.

It turns out Yersinia pestis contains a particular molecule that represses the function of pyrin in healthy individuals. In doing so, the pathogen suppresses the body's inflammatory response to the infection. This way, the body cannot fight back.

"Inflammation is a process in which white blood cells protect the body from infection. From the host's point of view, inflammation helps us survive. From the bacteria's point of view, inflammation is something to be evaded by any means available," said Daniel Shriner, Ph.D., staff scientist in the Center for Research on Genomics and Global Health at NHGRI.

Researchers were struck by the fact that Yersinia pestis affects the very protein that is mutated in FMF. They considered the possibility that FMF-causing genomic variants may protect individuals from the bubonic plague caused by Yersinia pestis.

The idea that evolution would push for one disease in a group to fight another may seem counterintuitive. But it comes down to what is the least bad option.

The average mortality rate of people with bubonic plague over centuries has been as high as 66%, while, even with a carrier frequency of 10%, less than 1% of the population has FMF. Theoretically, the evolutionary odds are in the latter's favor.

But first, the team had to verify if two of the genomic variants that cause FMF had indeed undergone positive selection in Mediterranean populations.

For this, they performed genetic analysis on a large cohort of 2,313 Turkish individuals. They also examined genomes from 352 ancient archaeological samples, including 261 from before the Christian era. The researchers tested for the presence of two FMF-causing genomic variants in both groups of samples. They also used population genetics principles and mathematical modeling to predict how the frequency of FMF-causing genomic variants changed over generations.

"We found that both FMF-causing genomic variants arose more than 2,000 years ago, before the Justinian Plague and the Black Death. Both variants were associated with evidence of positive selection," said Elaine Remmers, Ph.D., associate investigator in NHGRI's Metabolic, Cardiovascular and Inflammatory Disease Genomics Branch.

Researchers then studied how Yersinia pestis interacts with FMF-causing genomic variants. They took samples of particular white blood cells from FMF patients. In addition, they took samples from people who carry just one copy of the genomic variants (hence, do not get the disease).

The team found that Yersinia pestis does not reduce inflammation in white blood cells acquired from FMF patients and people with one copy of FMF-causing genomic variants. This finding is in stark contrast to the fact that Yersinia pestis reduces inflammation in cells without FMF-associated mutations.

The researchers thought that if Yersinia pestis does not reduce inflammation in people with FMF, then perhaps this could potentially increase patients' survival rate when infected by the pathogen.

To test this hypothesis, the researchers genetically engineered mice with FMF-causing genomic variants. They infected both healthy and genetically engineered mice with Yersinia pestis. Their results showed that infected mice with the FMF-causing genomic variant had significantly increased survival as compared to infected healthy mice.

These findings, in combination, indicate that over centuries, FMF-causing genomic variants positively selected in Turkish populations play a role in providing resistance to Yersinia pestis infection. Whether the same is true for other Mediterranean populations remains to be seen. The study offers a glimpse into the unexpected and long-lasting influence of microbes on human biology.

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BU study: Nearly half of US youth have been stalked/harassed by partners

BOSTON UNIVERSITY SCHOOL OF MEDICINE

 

A new, first-of-its-kind Boston University School of Public Health (BUSPH) study finds that 48% of 12-18-year-olds who have been in a relationship have been stalked or harassed by a partner, and 42% have stalked or harassed a partner.

Published in the journal Youth & Society, the analysis is part of the first nationally-representative study of non-physical youth dating abuse.

"These victimization and perpetration numbers are unacceptably high," says study lead author Dr. Emily Rothman, professor of community health sciences at BUSPH. "Unfortunately, they are in line with estimates of similar problems like dating and sexual violence victimization, so they are both shocking and unsurprising at the same time."

Previous research shows that harassing and stalking behaviors, including destroying belongings or going through social media accounts, can lead to physical violence, Rothman says.

But perhaps especially in the time of COVID, non-physical dating abuse needs to be recognized as real and harmful in its own right, she says.

"Adolescents have already been fully aware of how harmful online forms of abuse can be--that it's valid to be interested in that and to try to address it," Rothman says. "COVID has in some ways made parents, teachers, and other adults more willing to see, right now, that what we do online matters and is fully part of our real lives."

Rothman and colleagues from NORC at the University of Chicago used data from the ongoing Survey on Teen Relationships and Intimate Violence (STRiV) study to look at responses from 148 boys and 172 girls who were currently in relationships or had been in relationships in the past year. The survey asked teens if a partner had ever followed or spied on them, damaged something that belonged to them, or gone through their online accounts. The survey also asked the teens if they had ever done any of these things to a partner.

They found that rates of perpetration and victimization were similar for boys and girls: 46.5% of boys and 50.6% of girls reported stalking or harassing a partner, and 44.6% of boys and 51.1% of girls reported a partner doing these things to them.

The researchers analyzed and controlled for a range of other factors to better understand why particular teens may be at higher risk of perpetration, victimization, or both.

Among boys, having worse relationships with parents and living in neighborhoods with higher rates of violent crime were both associated with higher risk of perpetration. Among girls, being in relationships at younger age, living in neighborhoods with higher rates of violent crime, using marijuana, and using alcohol were associated with higher risk of victimization and perpetration. By race/ethnicity, the researchers found that Latino boys and Black girls faced higher risk of both victimization and perpetration.

Further research will need to untangle these associations, but Rothman says the findings show that dating abuse is shaped by forces larger than the individual.

"We know from intervention research that the way to prevent stalking and harassment, or sexual and dating violence, is partly about addressing how young people think about relationships, gender norms, and improving their social-emotional skills, but these are also influenced by the context in which they are operating," she says.

"So, addressing racism, poverty, homophobia, misogyny, and disability-related discrimination is part of the solution, too."

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About the Boston University School of Public Health

Founded in 1976, the Boston University School of Public Health is one of the top five ranked private schools of public health in the world. It offers master's- and doctoral-level education in public health. The faculty in six departments conduct policy-changing public health research around the world, with the mission of improving the health of populations--especially the disadvantaged, underserved, and vulnerable--locally and globally.

Microbiome confers resistance to cholera

Not everyone exposed to infectious diarrhea-causing bacteria gets sick

UNIVERSITY OF CALIFORNIA - RIVERSIDE

 

IMAGE: VIBRIO CHOLERAE BACTERIUM, WHICH IS RESPONSIBLE FOR CAUSING CHOLERA. view more 

CREDIT: CENTERS FOR DISEASE CONTROL AND PREVENTION

Cholera can kill within hours if left untreated, and it sickens as many as 4 million people a year. In a new article in the journal Cell, researchers describe how gut bacteria helps people resist the disease.

Bacteria live everywhere on the planet -- even inside the human body. UCR microbiologist Ansel Hsiao studies whether the bacteria living in our bodies, collectively known as the human microbiome, can protect people from diseases caused by external bacteria such as Vibrio cholerae, which lives in waterways and causes cholera.

Hsiao's team examined the gut microbiomes from people in Bangladesh, where many suffer from cholera as a result of contaminated food, water and poor sanitation infrastructure. "When people get sick, the diarrhea gets flushed into water systems that people drink from, and it's a negative cycle," Hsiao explained.

His team wanted to see whether prior infections or other stresses, like malnutrition, make people more vulnerable, as compared to Americans who don't face these same pressures.

The findings surprised the group, which expected stressed Bangladeshi microbiomes would allow for higher rates of infection. Instead, they saw infection rates varied greatly among individuals in both populations, suggesting susceptibility is based on a person's unique microbiome composition -- not the place they're from.

Vibrio cholerae spends most of its time outside of humans in aquatic environments. It doesn't usually encounter bile, which mammals produce to help digest fats after a meal.

"Because bile is specific to the intestines of humans and animals, many microorganisms, including cholerae, have evolved ways to deal with it," Hsiao said.

Once Vibrio cholerae enters a body, the presence of bile and lack of oxygen in the gut triggers previously dormant genes that enable it to survive in its human host. These genes are responsible for cholera's virulence, helping Vibrio cholerae attach to intestinal walls and cause diarrhea.

Hsiao's team identified one bacterium in the human microbiome, Blautia obeum, that can deactivate the cholera bacterium's disease-causing mechanisms, preventing it from colonizing the intestines. They also figured out how this feat is accomplished.

Cholera patients in Haiti, where an outbreak of cholera occurred after a 7.0 earthquake in 2010

Kendra Helmer/USAID

Blautia obeum produces an enzyme that degrades salts in bile, which Vibrio cholerae uses as signals to control gene activity. When these bile salts are corrupted, the cholera-causing bacteria does not receive the signal to activate the dormant genes that cause infection.

Since it's become clear that more Blautia obeum makes people less susceptible to cholera, a focus of future studies will be how to increase its presence in the gut. "We are extremely interested now in learning which environmental factors, such as diet, can boost levels of obeum," Hsiao said.

Similar studies are also underway with regard to the virus causing another global pandemic -- SARS-CoV-2. Hsiao is collaborating with several groups trying to understand how the microbiome changes with COVID-19 infection.

"One day, we may also understand whether and how the microbiome affects COVID-19 and makes people resistant to other illnesses we don't currently have treatments for," Hsiao said.

Ad blockers may benefit websites, users, and the market at large

SHARE THIS WITH ALL THOSE NEWS SITES NOW BLOCKING AD BLOCKERS

CARNEGIE MELLON UNIVERSITY

 

Millions of websites, including some of the largest Internet companies (e.g., Google, Yahoo), depend on advertising as their main source of revenue, allowing them to offer their content for free. The use of software that blocks ads has surged in recent years, presenting a challenge to platforms that depend on ad revenue. A new study sought to determine the effect of ad blockers on websites' ability to generate revenue and on users' experiences. The study found that contrary to common assumptions, ad blockers may offer some benefits to companies, users, and the market at large. The findings have implications for how online platforms make decisions about advertising.

The study, by researchers at Carnegie Mellon University and the City University of Hong Kong, appears in Management Science.

"While most speculations point to a grim outlook for advertisers and platforms as a result of ad blockers, the results of our study offer a glimmer of hope by arguing that ad blockers could actually benefit companies," suggests Kannan Srinivasan, Professor of Management, Marketing, and Business Technologies at Carnegie Mellon University's Tepper School of Business, who coauthored the study.

An ad blocker is a type of software, usually added by a user as an extension to an Internet browser, that prevents ads from appearing on the browsed webpages. When a user with an ad blocker visits a website with ads, the blocker identifies the ad content and prevents it from loading--as a result, the website does not receive ad revenue for that user.

Researchers devised an analytical model to assess the effects of ad blockers by modeling competition, the rate of advertising, and users' sensitivity to advertising. The authors identified two classes of users: one that is more sensitive to ads and uses ad blockers and one that does not use ad blockers. Based on the prevailing conditions, each platform had three options to manage the potential use of ad blockers by some users:

1. Ban ad blocking: Continue displaying ads and ban ad blocking. If a viewer used an ad blocker, he or she has to disable it to gain access to the site.
2. Allow ad blocking: Continue to display ads and allow ad-blocking software by any user who installs it.
3. Charge fees for ad blocking: Stop displaying ads and offer only an ad-free site with a subscription fee.

Based on their work, the researchers concluded that ad blockers may be helpful in one of four ways:

• They can make the market more efficient by filtering users who are sensitive to general ads, allowing websites to target more intense ads to the rest of the users.
• They benefit users by allowing the removal of ads that annoy them.
• They help regulate the ad industry by motivating the advertising platform to pay a fee to the ad-blocking company to include it in a list of ads that are allowed past the blocker.
• A more efficient market can boost the quality of websites' content, which also benefits users.

"Our study has implications for platforms dependent on ad revenue, providing general guidelines regarding how they should proceed with decisions about advertising," according to Stylianos Despotakis, Assistant Professor of Marketing at the City University of Hong Kong, who coauthored the study. "For example, if a website has users who are generally sensitive to ads, then its platform cannot expect to receive a lot of ad revenue, even when it prevents the use of ad blockers. By allowing ad blockers, both the platform and the users can benefit."

R. Ravi, Professor of Operations Research and Computer Science at Carnegie Mellon University's Tepper School of Business and a coauthor of the study, adds: "To estimate users' ad sensitivities, platforms can do tests under differing conditions to decide the ideal course of action to manage ad blocking."

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Study: Gay and bisexual youth more likely to abandon churchgoing as they reach adulthood

Prayer remains important to many, however

UNIVERSITY OF NEBRASKA-LINCOLN

 

Religious beliefs have shaped societal attitudes toward sexual minorities, with many religious denominations vocally opposing expanded sexual minority rights. Because of this stigmatization, lesbian, gay and bisexual individuals are less likely to affiliate with a religious group -- but research from the University of Nebraska-Lincoln and Old Dominion University suggests they are not abandoning their faith altogether.

In a new study, sociologists Brandi Woodell and Philip Schwadel found that emerging adults -- from adolescence to early adulthood -- with same-sex attraction are twice as likely to disaffiliate from organized religion than their heterosexual peers, but there was little change in prayer.

"I think that is something we expected, that there'd be a difference between affiliation on one hand and prayer on the other," said Schwadel, Happold Professor of Sociology at Nebraska. "In the previous research on adolescent religion, in particular, and in later adolescence or early emerging adulthood, we see a lot of declines in the organized aspects of religion, but we see less of a decline in prayer. Prayer is something people can often do on their own at home or wherever they want."

And, not in an environment that may be stigmatizing toward sexual minorities, the authors wrote in the paper.

The scholars used two longitudinal surveys, the National Longitudinal Study of Adolescent to Adult Health, and the National Study of Youth and Religion to examine -- for the first time -- these declines in religiosity over time for sexual minorities in emerging adulthood.

"Almost all previous research was cross-sectional, only looking at, 'do people who identify as gay or lesbian -- are their religious activities and beliefs different?'" Schwadel said. "It didn't look at how they change over time, especially during this stage of the life course, when individuals are really figuring out who they are."

The study also showed a significant difference in religiosity declines between gay and bisexual individuals, further demonstrating that sexual minorities are not a monolithic group.

Woodell, a 2018 Nebraska alumna and assistant professor of sociology at Old Dominion University in Norfolk, Virginia, said this study joins a novel line of research examining the differences between bisexual, gay and lesbian individuals.

"Past research has most often combined sexual minorities into one group, and that was largely due to a lack of data that separated them, but some newer research has suggested there are differences, which led us to separate the groups out," Woodell said. "We found that those who identify as bisexual show a greater decline in their religious attendance than gay and lesbian individuals."

This difference could be explained by some research that has found bisexuals are less likely to be accepted than their gay counterparts, even in affirming denominations, Woodell said.

"There is newer research showing that bisexuals have experienced stigmatization in their congregation because their sexuality is viewed as a choice," Woodell said.

While the study found little change in prayer among the sexual minority groups, there was a small decline among bisexuals. Schwadel and Woodell said they are pursuing this research further, breaking down differences among gender.

"We're currently looking at how these things differ for men and women," Schwadel said. "We know that gender is strongly related to religiosity, and we expect that gender plays a role in terms of how sexuality is related to religious change."

Further research is also needed, they said, to examine how these declines in religiosity among lesbian, gay and bisexual individuals continue to change in later adulthood.

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Study: New leaders emerge as organizations go to virtual work spaces

In virtual environments, actions trump more traditional leadership traits

BRIGHAM YOUNG UNIVERSITY

 

When work meetings shifted online this spring, some may have noticed new standouts among their colleagues. According to new research, members of virtual teams identify leaders in significantly different ways compared to members of in-person teams.

The brand new study looked at "emergent leaders"--those who lack formal authority but are recognized as leaders by team members--in teams with varying levels of virtual interaction. Researchers found that in face-to-face gatherings, team members value those with "classic" leadership characteristics, such as extroversion and intelligence, but in virtual settings, those qualities take a backseat.

Online, perhaps because there are fewer cues available for human interaction and more opportunities for miscommunication, team members gravitate toward those who take concrete steps to ensure achievement, rather than toward those with charismatic personalities.

"On a virtual team, it's more important than in a face-to-face meeting to stand out as the one who helps others," said study coauthor Cody Reeves, an assistant professor at the Marriott School of Business at Brigham Young University. "Those who take the time to pause and assist others with tasks are more likely to be viewed as leaders."

Perceived differences between virtual and in-person leaders were "stark," according to Reeves. While it remained essential for leaders in virtual teams to connect socially, successful leadership online was driven primarily by small actions like monitoring timelines, providing feedback, and coordinating teamwork.

For the study, researchers observed 220 student teams at two Midwestern universities who met to work on assigned projects mostly virtually, mostly in person or in a mix of the two. The students completed surveys about their own and their team members' characteristics and behaviors, as well as whom they considered to be team leaders. Combining that data with transcripts of the students' virtual interactions, the researchers identified patterns in how leaders emerge across the spectrum of virtual to in-person teams.

As virtual work becomes more common for organizations, managers and team members alike would benefit from understanding that leadership traits and behaviors impact leadership perceptions differently in different virtual contexts, authors said. For example, organizations should not automatically promote individuals who have distinguished themselves as emergent leaders from a more in-person (and low virtual) context to leadership roles in a highly virtual context.

"In virtual environments, our actions speak loudly," said fellow study author Steven Charlier, a professor of management at Georgia Southern University. "The 'soft' skills that traditional managers rely on might not translate easily to a virtual environment."

Reeves agreed, noting that "a 'natural leader' who doesn't usually engage in these specific leader-like behaviors but always kind of 'has it' needs to be extra careful--because those are the types that are at the highest risk of no longer being viewed as a leader in virtual contexts."

With the "new normal" of work online, "now is the time for organizations and employees to gain virtual leadership competencies," said study lead author Radostina Purvanova of Drake University. "These are the skills of the future. Those companies that have already embraced virtuality are now reaping the benefits -- and the rest of us must catch up quickly, or else we will simply be left behind."

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The study was also co-authored by Lindsey M. Greco of Oklahoma State University and is published in the Journal of Business and Psychology.

Raw milk may do more harm than good

Not properly stored, it's a source of antibiotic-resistant microbes

UNIVERSITY OF CALIFORNIA - DAVIS

Raw or unpasteurized cows' milk from U.S. retail stores can hold a huge amount of antimicrobial-resistant genes if left at room temperature, according to a new study from researchers at the University of California, Davis. The study also found bacteria that harbored antimicrobial-resistant genes can transfer them to other bacteria, potentially spreading resistance if consumed. The study was published in the journal Microbiome.

"We don't want to scare people, we want to educate them. If you want to keep drinking raw milk, keep it in your refrigerator to minimize the risk of it developing bacteria with antibiotic-resistant genes," said lead author Jinxin Liu, a postdoctoral researcher in the Department of Food Science and Technology at UC Davis.

LACKING IN PROBIOTICS

An estimated 3 percent of the U.S. population consumes unpasteurized, or raw, milk, which has not been heated to kill pathogens and extend shelf life. Raw milk is often touted to consumers as having an abundant supply of probiotics, or healthy bacteria, compared with pasteurized milk. UC Davis researchers did not find that to be the case.

"Two things surprised us," said Liu. "We didn't find large quantities of beneficial bacteria in the raw milk samples, and if you leave raw milk at room temperature, it creates dramatically more antimicrobial-resistant genes than pasteurized milk."

Bacteria with antimicrobial-resistant genes, if passed to a pathogen, have the potential to become "superbugs," so that pharmaceuticals to treat infection or disease no longer work. Each year, almost 3 million people get an antibiotic-resistant infection, and more than 35,000 people die, according to the Centers for Disease Control.

THE LONGER IT SITS, THE WORSE IT GETS

UC Davis researchers analyzed more than 2,000 retail milk samples from five states, including raw milk and milk pasteurized in different ways. The study found raw milk had the highest prevalence of antibiotic-resistant microbes when left at room temperature.

"Our study shows that with any temperature abuse in raw milk, whether intentional or not, it can grow these bacteria with antimicrobial resistance genes," said co-author Michele Jay-Russell, research microbiologist and manager with the UC Davis Western Center for Food Safety. "It's not just going to spoil. It's really high risk if not handled correctly."

Some consumers are intentionally letting raw milk sit outside of the refrigerator at room temperature to ferment, in order to make what's known as clabber. Co-author and Peter J. Shields Chair of Dairy Food Science David Mills said if consumers eat raw milk clabber, they are likely adding a high number of antimicrobial-resistant genes to their gut.

"You could just be flooding your gastrointestinal tract with these genes," said Mills. "We don't live in an antibiotic-free world anymore. These genes are everywhere, and we need to do everything we can to stop that flow into our bodies."

While more work is needed to fully understand whether antibiotic-resistant genes in raw milk translate into health risks for humans, Mills suggests that consumers instead use a starter culture if they want to ferment raw milk, which carries specific strains of bacteria to inoculate the milk.

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Other authors include Yuanting Zhu of UC Davis and Danielle Lemay of USDA ARS Western Human Nutrition Research Center. This study was funded with support from the National Institutes of Health and the Peter J. Shields Endowed Chair in Dairy Food Science.

New eye drops may prevent a common cause of blindness

COLUMBIA UNIVERSITY IRVING MEDICAL CENTER

 

IMAGE: EYEDROPS WITH A CASPASE-9 INHIBITOR PREVENT RETINAL INJURY FROM RETINAL VEIN OCCLUSION. IN THE LEFT IMAGE, RVO CAUSES SWELLING IN THE RETINA AND THE RETINAL LAYERS ARE LESS DISTINCT.... view more 

CREDIT: TROY LAB (CUIMC)

NEW YORK, NY (June 29, 2020) -- Researchers at Columbia University Irving Medical Center have developed eye drops that could prevent vision loss after retinal vein occlusion, a major cause of blindness for millions of adults worldwide.

A study, in mice, suggests that the experimental therapy -- which targets a common cause of neurodegeneration and vascular leakage in the eye -- could have broader therapeutic effects than existing drugs.

The study was published in Nature Communications.

What is Retinal Vein Occlusion?

Retinal vein occlusion occurs when a major vein that drains blood from the retina is blocked, usually due to a blood clot. As a result, blood and other fluids leak into the retina, damaging specialized light-sensing neurons called photoreceptors.

Standard treatment for the condition currently relies on drugs that reduce fluid leakage from blood vessels and abnormal blood vessel growth. But there are significant drawbacks. These therapies require repeated injections directly into the eye, and for the patients who brave this daunting prospect, the treatment ultimately fails to prevent vision loss in the majority of cases.

The new treatment targets an enzyme called caspase-9, says Carol M. Troy, MD, PhD, professor of pathology & cell biology and of neurology in the Taub Institute for Research on Alzheimer's Disease and the Aging Brain at Columbia University Vagelos College of Physicians and Surgeons, who led the studies. Under normal conditions, caspase-9 is believed to be primarily involved in programmed cell death, a tightly regulated mechanism for naturally eliminating damaged or excess cells.

However, in studies of mice, the Troy lab discovered that when blood vessels are injured by retinal vein occlusion, the caspase-9 becomes uncontrollably activated, triggering processes that can damage the retina.

Eye Drops Prevent Retinal Injury

The Troy lab found that a highly selective caspase-9 inhibitor, delivered in the form of eye drops, improved a variety of clinical measures of retinal function in a mouse model of the condition. Most importantly, the treatment reduced swelling, improved blood flow, and decreased neuronal damage in the retina.

"We believe these eye drops may offer several advantages over existing therapies," says Troy. "Patients could administer the drug themselves and wouldn't have to get a series of injections. Also, our eye drops target a different pathway of retinal injury and thus may help patients who do not respond to the current therapy."

Next Steps

The researchers are preparing to test the eye drops in people with retinal vein occlusion during a phase I clinical trial.

Moving forward, the Troy lab will also study whether caspase-9 inhibitors can be used to treat other vascular injuries caused by overactivation of the enzyme, including diabetic macular edema (another common cause of blindness) and stroke.

"Vascular dysfunction is at the heart of many chronic neurological and retinal disorders, because high energy demands in the brain and eye render these tissues exceptionally vulnerable to disruption in blood supply," says the study's first author, Maria Avrutsky, PhD, postdoctoral research scientist in pathology & cell biology at Columbia University Vagelos College of Physicians and Surgeons.

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More Information

The study is titled, "Endothelial activation of caspase-9 promotes neurovascular injury in retinal vein occlusion."

The other contributors, all from Columbia University Irving Medical Center except where indicated, are: Crystal Colón Ortiz, Kendra V. Johnson, Anna M. Potenski, Claire W. Chen, Jacqueline M. Lawson, Alexandra J. White, Stephanie K. Yuen, Fatima N. Morales, Elisa Canepa, Scott Snipas (Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA), Guy S. Salvesen (Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA), and Ying Y. Jean.

The study was funded by grants from the National Institute of Neurological Disorders and Stroke (RO1 NS081333, R03 NS099920), the National Eye Institute (T32 EY013933), the National Science Foundation (DGE-1644869), the National Institute on Aging (T35 AG044303), the National Institute of General Medical Sciences (R01GM09040), and the Department of Defense Army/Air Force.

The following authors have patent applications related to this research: Dr. Troy (US20150165061), Drs. Troy, Salvesen, and Snipas (US 20140024597), and Drs. Troy and Jean (WO2018013519). The remaining authors declare no competing interests.

Columbia University Irving Medical Center provides international leadership in basic, preclinical, and clinical research; medical and health sciences education; and patient care. The medical center trains future leaders and includes the dedicated work of many physicians, scientists, public health professionals, dentists, and nurses at the Vagelos College of Physicians and Surgeons, the Mailman School of Public Health, the College of Dental Medicine, the School of Nursing, the biomedical departments of the Graduate School of Arts and Sciences, and allied research centers and institutions. Columbia University Irving Medical Center is home to the largest medical research enterprise in New York City and State and one of the largest faculty medical practices in the Northeast. For more information, visit cuimc.columbia.edu or columbiadoctors.org.