Wednesday, September 16, 2026

TBI

Blast exposure in military associated with conditions like seizures, stroke years later

American Academy of Neurology

Highlights:

Exposure to high-level blasts among military veterans is associated with an increased risk of conditions such as seizures, neuropathy and stroke years later.
The study does not prove that exposure to blasts causes these conditions; it only shows an association.
The study involved 36,641 veterans who had received care at the Veterans Health Administration.
The findings support monitoring people with high-level blast exposure for the development of cardiovascular, metabolic, neurological and other conditions, according to the study author.

MINNEAPOLIS — Exposure to high-level blasts from incoming explosive devices or land mines among military veterans is associated with an increased risk of several conditions such as seizures, neuropathy and stroke years later, according to a study published September 16, 2026, in Neurology®, the medical journal of the American Academy of Neurology. The study does not prove that exposure to blasts causes these conditions; it only shows an association.

“Blast exposure is often viewed through the lens of acute injury and brain health, but our findings reinforce that blast exposure is a whole-body problem with health implications that extend well beyond the time of exposure,” said study author Sarah L. Martindale, PhD, of the Salisbury VA Health Care System in North Carolina. “In this study, veterans with a history of high-level blast exposure were more likely to be diagnosed with a range of neurological, respiratory, cardiovascular, and metabolic conditions years later.”

The study involved 36,641 veterans who received care at the Veterans Health Administration for at least two years during the study after leaving military service. The participants completed a survey on exposure to blasts and then were followed for up to 10 years. The researchers also looked at participants’ occupations to determine exposure to low-level blasts from outgoing munitions such as heavy artillery or shoulder-fired weapons.

A total of 11% of participants reported exposure to at least one high-level blast and 17% were in an occupation with a high risk of low-level blasts. About 5% had both exposures.

Researchers found that exposure to high-level blasts was associated with increased likelihood of many conditions, including hepatitis B and C, seizures, diabetes, stroke, neuropathy, high cholesterol and the lung diseases chronic bronchitis and emphysema.

For seizures, 3.92% of veterans reported exposure to high-level blasts compared to 1.88% of those with no blast exposure. For neuropathy, prevalence was 11.41% of those with exposure compared to 7.75% of those who did not report blast exposure. For stroke, 2.03% of veterans exposed to high-level blasts compared to 1.62% of those with no exposure.

Once researchers adjusted for other factors that could affect the prevalence of these conditions, such as age, sex and total number of days deployed, they found that veterans with high-level blast exposure were 79% more likely to have a seizure diagnosis, 38% more likely to be diagnosed with neuropathy and 35% more likely to have a stroke diagnosis..

For low-level blast exposure, researchers found that service members were less likely to be diagnosed with conditions such as diabetes, high cholesterol and Crohn’s disease. However, Martindale noted that several factors could have affected these findings, including that many of the participants were relatively young at the start of the study and the follow-up period may not have been long enough for conditions to develop. She said the absence of elevated risk from low-level exposure in this study should not be interpreted as evidence that low-level exposure to blasts has no long-term physical health consequences.

“Understanding a veteran’s history of blast exposure may give us another piece of the puzzle when considering their long-term health risks and how those risks should be monitored over time,” Martindale said.

A limitation of the study was that exposure to high-level blasts was reported by participants and no information was available about the intensity of the blast, type and severity of injuries or treatment. Also, information on diagnosis of conditions was limited to cases documented through the VA health care system after the survey. Diagnoses occurring before the start of the study or outside the VA system were not captured.

The study was supported by the Salisbury VA Health Care System, Naval Health Research Center, VA Puget Sound Health Care System and the Henry M. Jackson Foundation for the Advancement of Military Medicine.

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Journal

Neurology

DEI

Gender representation key to women’s job interest, study suggests

The research comprised analyses of a series of questionnaire experiments

Emory University

Women make up about half the U.S. population, yet remain in the minority in many professions, such as politics, technology, science and academia.

A key reason for this disparity is that women prefer to work in fields with more female representation, suggests new research by psychologists at Emory University. The journal PLOS One published the findings.

The research comprised analyses of a series of questionnaire experiments, including some involving hypothetical advertisements for employment.

The results showed the effect of gender demographics on responses of participants was robust, particularly among women. Women were more likely to express interest in jobs portrayed as having more female representation — even when the required abilities specified by the ads were ones stereotypically associated with men.

“Some people may think of gender representation as mostly symbolic — that it’s simply nice for women to see themselves represented in a field,” says Stella Lourenco, Emory professor of psychology and first author of the study. “What we found is that gender representation is more consequential. It is perhaps a primary reason women decide whether to enter a particular occupation in the first place.”

Co-authors of the study include Arber Tasimi, Emory assistant professor of psychology; Kylee Novick, who did the work as an Emory undergraduate student of psychology and has since graduated; and Ryno Kruger, who worked on the project as an Emory graduate student and is currently an assistant professor of psychology at Brigham Young University.

Lingering disparities

One hundred years ago, most women in the United States did not work outside the home. Their workplace presence kept growing over the decades, however, as societal norms changed and more doors began opening for the female sex.

By 2023, 77% of prime working-age women held jobs outside the home, according to the U.S. Bureau of Labor Statistics. Women have forged careers in many fields where their numbers were once few. And yet, large disparities in gender representation remain in many crucial sectors.

Research has shown that an array of factors likely account for this phenomenon.

‘Brilliance’ vs ‘dedication’

Recent work, for instance, supports the field-specific ability beliefs (FAB) theory. FAB posits that female underrepresentation in a field may reflect societal stereotypes that link men, but not women, with “brilliance,” or intrinsic aptitude. In this scenario, women may feel unwelcome in fields believed to emphasize brilliance, such as philosophy, economics and science, technology, engineering and mathematics.

On the flip side, FAB posits that women may feel more welcome in fields such as education and nursing, reflecting a stereotype that women are better suited to fields perceived to require more dedication and diligence than brilliance.

Research has also delved into potential impacts on women’s career choices of what has been called “masculinity contest culture.” The term applies to fields, such as technology, perceived to emphasize stereotypical male traits of aggressiveness, assertiveness, independence, ambition and competitiveness.

“We wanted to tease out to what extent current gender representation matters to women’s career preferences,” Lourenco says. “Does it matter more than perceptions about what it takes to succeed in a particular field and the workplace culture associated with it?”

Inherent beliefs

The researchers recruited U.S. participants for a series of studies on the online testing platform Prolific. A total of 1,680 adults, ages 18 to 64, participated, including 851 women and 829 men.

In the first study, a group of participants were presented with an occupation and asked to use a sliding scale to estimate the gender ratio within that occupation. The results showed that participants’ average estimates significantly correlated with actual gender representation across 60 different fields.

To assess their inherent beliefs about these fields, participants were asked to respond to a series of statements on a sliding scale, from “strongly disagree” to “strongly agree.” Examples of these statements include:

“This job requires a special aptitude that just can’t be taught.”
“With the appropriate training and resources, I feel like I would belong in this occupation.”
“In this job, one person’s loss is another person’s gain.”

They were also asked to respond on a sliding scale of “not at all similar” to “very similar” to the question:

“How similar do you think you are to the other people who hold this occupation?”

Analysis of the results largely supported previous research, suggesting that beliefs about brilliance, dedication and the culture of the workplace contribute to people’s interest in different jobs. Women showed a preference for jobs associated with dedication; while men showed a preference for those emphasizing brilliance and competition.

The results also extended the work by showing the importance of perceived gender demographics, particularly among women. The greater the expected female representation, the higher women’s anticipated belonging, even after accounting for effects of FAB and, in some cases, for masculinity contest culture and ratings of their feelings of similarity to prototypical characteristics of individuals within the field.

Hypothetical ads

In a separate study, participants were presented with hypothetical job advertisements that either emphasized the need for brilliance or dedication in the role. The ads also provided explicit information about the male-female distribution in each job. Participants were asked to rate their interest in applying for each position and their anticipated sense of belonging if they got the job.

Strikingly, anticipated belonging among women participants was even higher for a female-dominated job that emphasized brilliance compared to a male-dominated job that emphasized dedication.

In this experiment, men’s ratings of an anticipated sense of belong for hypothetical jobs were largely unaffected by either messaging of brilliance versus dedication or by gender representation.

Percentage matters

In another study, the researchers did a quantitative test of how gender demographics may shape interest and a sense of belonging for future employment. Participants were presented with hypothetical job advertisements that included the ratio of male versus female colleagues.

The higher the ratio of women in the female-dominated jobs, the stronger the women’s ratings were for belonging. Men also expressed greater anticipated belonging for jobs with their gender majority, although they showed less variation in anticipated belonging as a function of gender ratio.

A self-reinforcing cycle

Throughout the studies, women’s responses consistently placed a higher value on female representation compared to other variables in the job advertisements.

“One hypothesis is that gender representation may be a proxy for workplace climate,” Lourenco says, signaling expectations about support, inclusivity and competitiveness.

For example, she says, women may believe that fields represented by fewer women are also more likely to be fields with masculine-stereotyped competitive culture.

“Gender representation is often spoken of simply as a result of women choosing not to work in a particular field,” Lourenco adds. “Our work suggests that gender representation is also an important underlying cause of fewer women choosing to work in certain fields. It’s really a self-reinforcing cycle. Today’s gender representation likely plays a role in shaping tomorrow’s gender representation.”

The work was funded by the Templeton World Charity Foundation.

Journal

PLOS One

DOI

10.1371/journal.pone.0351865

Method of Research

Survey

Subject of Research

People

Article Title

Gender representation begets gender representation

NATURE IS AN ANARCHIST

Rich neighborhoods more likely to burn

Wealthy enclaves at higher risk, but bounce back faster

University of California - Riverside

Burning home — image:
Firefighters battling a blaze that consumed a house.
view more
Credit: Ada Be

Frequently located on hillsides and in canyons surrounded by wildlands, rich neighborhoods are more likely to catch fire. However, a UC Riverside study shows they are also likely to recover faster than lower-income areas.

Unlike most fire research focused on wildland blazes or single catastrophic events, the UCR study represents one of the most comprehensive looks at the unique dynamics of fires in cities.

Published in the journal NPJ Urban Sustainability, the study examined 141 fires across the U.S. going back to 1984. Combining these records with population, development, climate, and demographic data offered a more in-depth understanding of the lead-up to and aftermath of fires.

The results show that risk of fire in cities is not distributed randomly. “These urban fires consistently occur in suburban, high-income, owner-occupied development,” said UCR postdoctoral researcher in urban ecology and study author Dion Kucera. “That hasn’t changed in more than 40 years.”

According to the study, neighborhoods with substantially higher median incomes had about 30% higher odds of fire exposure.

One of the study's most critical findings for city planners is what precedes these fires. It’s not long-term drought, but rather a short, intense drying of the environment in the six months prior. “That suggests three- to six-month moisture measures may be more important for city managers trying to identify periods of heightened risk, rather than longer-term drought assessments,” Kucera said.

Once a neighborhood burns, recovery can be slow. The researchers measured whether vegetation and surface temperatures returned to their pre-fire ranges during the following five years. For most places, they did not.

About 78% of severely burned areas failed to return to their pre-fire temperature range within five years, while 73% failed to recover their previous level of greenness. In general, burned urban areas became hotter and less green, with the effects persisting for years.

Income emerged as an important factor in recovery as well. Higher-income neighborhoods tended to recover their pre-fire temperatures more quickly and experienced smaller losses in vegetation.

The results suggest that understanding urban fire requires looking at the social characteristics of the places that burn. With these factors in mind, the researchers found important regional differences. Nationally, neighborhoods with higher proportions of white residents had lower odds of experiencing fire. In California and other dry parts of the West, however, that relationship was reversed, with white as well as Black populations experiencing greater odds of exposure.

The study also found that urban fires behave differently from fires in wildlands. While wildland fires have been growing both larger and more frequent, the number of fires reaching urban areas did not show a clear increase over the study period.

There was, however, evidence that the amount of urban land burned is increasing. The trend was heavily influenced by especially destructive fire years, suggesting that extreme years may be driving greater losses even without an increase in the overall number of fires.

These findings could have implications for how communities prepare for fire and how insurers assess risk, though the study did not examine insurance markets directly. Kucera said additional research should explore those questions.

More broadly, he argues that scientists need to stop treating fires that enter developed areas as simply extensions of wildland fire. Cities have their own patterns of exposure and recovery, shaped by where people build, who lives there, and the resources they have available.

“The urban fire problem isn’t just structured by climate like it is in wildlands,” Kucera said. “Adapting to the growing intensity of urban fires requires looking beyond the forest and into the social fabric of our cities.”

Journal

npj Urban Sustainability

DOI

10.1038/s42949-026-00455-5

Article Title

Increasing burned area and unequal ecological recovery in U.S. urban-intersecting fires

BIDEN DEEP STATE

US officials suppressed warnings over flawed covid vaccine safety algorithm

Investigation reignites questions about what steps were taken to safeguard public health from any unintended consequences of the vaccination rollout

BMJ Group

US health officials knowingly relied on a compromised algorithm to detect signals of harm from mRNA covid-19 vaccines and silenced efforts to fix it, finds an investigation published by The BMJ today.

The findings are based on government emails released under the Freedom of Information Act and in response to US Senate investigators, as well as exclusive interviews with public health officials and other scientists by investigative journalist David Willman.

Before rolling out covid-19 vaccines in December 2020, the US Centers for Disease Control and Prevention (CDC) assured healthcare professionals and the public that its Vaccine Adverse Event Reporting System (VAERS) could quickly spot any potentially harmful reactions following vaccination.

The CDC planned to use two “data mining” techniques: “proportional reporting ratios” (PRRs) and an “empirical bayesian” method provided by the Food and Drug Administration (FDA), which operated VAERS jointly with the CDC. The two agencies planned to share and discuss results.

But according to a letter by CDC Director Rochelle Walensky, the agency did not perform PRR analyses until 2022, and both CDC and FDA “chose to rely” entirely on FDA’s bayesian method.

The BMJ can reveal that the FDA’s algorithm failed to signal a potential relationship between mRNA covid vaccination and myocarditis (inflammation of the heart muscle), pericarditis (inflammation of the fluid-filled sac around the heart), Bell’s palsy, tinnitus, and other reported disorders owing to a flaw in the detection methodology.

The problem arose because over 90% of initial VAERS reports were for the new mRNA covid vaccines made by Pfizer and Moderna. If both vaccines elevated the risk of an adverse event like myocarditis in roughly equal amounts, however, the “observed” frequency and “expected” frequency would be similar, resulting in no automated alert.

Internal records show that FDA officials were aware of this limitation before and during the pandemic. Government documents also show that CDC officials were informed during rollout of the vaccines.

In early 2021, FDA medical officer Dr Ana Szarfman, working with statistician William DuMouchel, who had developed the bayesian algorithm, warned top officials about the flaw and proposed an updated algorithm that flagged signals. But Szarfman was asked to “cease and desist.” Meanwhile, officials continued to cite the lack of system alerts while reassuring clinicians and the public of the vaccines' safety.

When the CDC finally ran PRR analyses in 2022, CDC director Walensky said results revealed “no additional unexpected safety signals.” Yet the analyses - examined by The BMJ - show hundreds of adverse events that met the agency’s alert criteria, including myocarditis, pericarditis, Bell’s palsy, and tinnitus, which the FDA’s bayesian method had not triggered.

In October 2023, the FDA’s pharmacovigilance chief acknowledged in an email to colleagues that the agency knew - as the vaccines had rolled out more than two years earlier - of the detection deficiency, but did not respond to requests for comment.

Approached by The BMJ, Szarfman insisted that she had not sought to undermine public support for the covid vaccines. Expressing frustration, she noted, “Very few people understand the statistics. That’s the problem.”

DuMouchel said he could not explain officials’ resistance to switch to the updated method, stating, “I think that they were wrong.” He also regretted that FDA officials rejected Szarfman's proposed fixes for VAERS, adding, “If they had paid attention to Ana, they would have done better.”

Journal

The BMJ

DOI

10.1136/bmj-2026-100806

Method of Research

News article

Subject of Research

People

Article Title

US officials knew covid vaccine safety system was flawed—but suppressed the FDA doctor who alerted them

Article Publication Date

16-Sep-2026

KAIST develops microbially produced adhesive materials from glucose instead of petroleum

Distinguished Professor Sang Yup Lee's team (Department of Chemical and Biomolecular Engineering) engineered the metabolic pathways of E. coli to produce polymers from glucose for adhesive applications

The Korea Advanced Institute of Science and Technology (KAIST)

KAIST Develops Microbially Produced Adhesive Materials from Glucose Instead of Petroleum — image:
Schematic summary of the study
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Credit: KAIST

KAIST researchers have demonstrated the potential of using microorganisms to produce a bio-based alternative to petroleum-derived materials for hot-melt adhesives. These heat-activated glues are widely used in packaging, furniture, electronics, and automobiles. Using Escherichia coli, the team produced a new polymer from glucose and demonstrated adhesive performance and thermal properties that support its potential use as a hot-melt adhesive.

KAIST (President Choongsik Bae) announced on September 17 that a research team led by Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering developed a microbial cell factory by engineering E. coli to produce the new aromatic polyhydroxyalkanoate (PHA) polymers from glucose for adhesive applications.

The research team applied systems metabolic engineering, an approach that redesigns a microorganism's overall metabolism to produce a target compound, to re-engineer the metabolic pathways of E. coli. Through this approach, the researchers successfully produced two new adhesive materials from glucose, poly(4HB-co-PhLA) and poly(3HB-co-4HB-co-PhLA), both belonging to the PHA family of biodegradable polymers.

Adhesives are essential materials used in a wide range of industries, including packaging materials, electronics, automobiles, and construction materials. In particular, hot-melt adhesives (HMAs) are solid adhesives that are melted with heat for bonding and then solidify as they cool. Because they do not require separate organic solvents and enable rapid bonding, they are widely used in industry.

However, most hot-melt adhesives currently in use are based on petroleum-derived polymers such as ethylene-vinyl acetate (EVA). Although they offer excellent adhesive performance, most do not readily degrade in nature and can cause waste and microplastic problems. In particular, even when biodegradable packaging materials are used, if the adhesive does not degrade, the biodegradability and recyclability of the entire product may be reduced.

To address this problem, the research team focused on PHA, a type of biodegradable plastic produced by microorganisms. PHA can be produced by microorganisms using renewable feedstocks such as glucose. It also has the advantage that properties such as polymer flexibility, strength, and heat resistance can be adjusted in various ways depending on which components are included and in what proportions.

Using this principle, the research team incorporated 4-hydroxybutyrate (4HB) and phenyllactate (PhLA) into a single polymer. 4HB contributes to the material’s softness and adhesion, while PhLA increases the material’s rigidity and heat resistance. When the research team varied the relative proportions of the two components, the thermal properties and adhesive performance of the polymers also changed. In particular, polymers containing approximately 24–34 mol% 4HB showed excellent adhesive performance.

The research team designed intracellular metabolic pathways so that E. coli consumes glucose, produces 4HB and PhLA on its own, and then links them together into polymers.

To address metabolic imbalances that arise when multiple monomers are produced simultaneously, the team adjusted the strength and timing of gene expression, added a CoA transferase to facilitate the reactions, and used a genome-scale metabolic model to identify and optimize metabolic pathways associated with insufficient precursor supply and production bottlenecks.

As a result, through fed-batch fermentation, in which nutrients are continuously supplied during microbial cultivation, the team successfully produced 10.2 g of poly(4HB-co-PhLA) per liter of culture medium. By additionally introducing a biosynthetic pathway for producing 3HB, the team successfully produced up to 52.8 g/L of poly(3HB-co-4HB-co-PhLA).

The research team also tested whether the produced polymers could be used as hot-melt adhesives.

In a lap shear adhesion test using stainless steel as the substrate, poly(4HB-co-PhLA) recorded a lap-shear strength of 4.58 MPa. This is higher than the 4.20 MPa achieved by a commercial EVA adhesive. Poly(3HB-co-4HB-co-PhLA) also showed performance comparable to EVA in a wood adhesion test.

In addition, poly(4HB-co-PhLA) retained a substantial level of adhesive strength even after repeated melting and rebonding. The incorporation of the PhLA component improved heat resistance.

Furthermore, after treatment with lipase, an enzyme that breaks down fats, surface damage to the polymers was observed, while the molecular weight and overall mass of the polymers also decreased. These results indicate that the newly developed aromatic PHA can be degraded by enzymes.

This study is significant not only for the development of an eco-friendly adhesive but also for demonstrating the potential of metabolic engineering to produce functional materials with tunable properties. Going forward, this approach could be extended into a biomanufacturing technology that tunes polymer properties, such as adhesion strength, flexibility, and heat resistance, to meet specific application needs, and produces such materials using microorganisms.

The approach also makes it possible to produce functional polymers that have traditionally been produced through petrochemical processes, from renewable feedstocks such as glucose instead. This is expected to serve as a sustainable production technology not only for adhesives but for a wide range of functional polymer materials going forward.

Distinguished Professor Sang Yup Lee said, “This study demonstrates that by engineering microbial metabolism, it is possible to go beyond simply producing polymers and directly produce functional materials,” adding, “In the future, by utilizing various non-natural monomers and microbial cell factories, this approach could be expanded into biomanufacturing technologies for the sustainable production not only of petroleum-based adhesive alternatives but also of a wide range of functional polymers.”

The study, co-authored by Ph.D. student Minju Kang, Dr. Youngjoon Lee, and Dr. Gi Bae Kim of the KAIST Department of Chemical and Biomolecular Engineering, was published online on July 20 in the international journal Nature Communications.

※ Paper title: Synthesis of poly(4HB-co-PhLA) and poly(3HB-co-4HB-co-PhLA) as sustainable hot-melt adhesives using engineered Escherichia coli. DOI: 10.1038/s41467-026-75809-9

※ Author information: Minju Kang (KAIST), Youngjoon Lee (KAIST), Gi Bae Kim (KAIST), Sang Yup Lee (KAIST, corresponding author)

This research was supported by the National Research Foundation of Korea through a grant funded by the Ministry of Science and ICT. (Grant No. 2022M3J5A1056117).

Journal

Nature Communications

DOI

10.1038/s41467-026-75809-9