Sunday, December 18, 2022

Why aren’t all black bears black?

Researchers at HudsonAlpha, the University of Memphis, and the University of Pennsylvania have discovered what causes cinnamon color coats in some black bears

Peer-Reviewed Publication

HUDSONALPHA INSTITUTE FOR BIOTECHNOLOGY

Sometimes a name is just a name. Take bears, for example. In Yellowstone National Park, black bears outnumber their brownish-colored grizzly bear cousins, and in coastal areas of the Pacific Northwest, if someone says “brown bear,” they mean grizzly bear. But not all brown bears are grizzly bears.

American black bears (Ursus americanus), which one would logically assume are, well, black, actually come in a range of colors, including brown (also known as cinnamon), blond, or bluish-grey. Others have coats that are a mixture of several colors. So, how do you tell a cinnamon-colored Ursus americanus from its brown (grizzly) Ursus arctos cousin? Differences in body shape and size can be subtle. One hypothesis for the cinnamon color of Ursus americanus is that it mimics the appearance of a grizzly bear, helping with camouflage or defense.

Now, researchers at HudsonAlpha, the University of Memphis, and the University of Pennsylvania, have discovered what causes the cinnamon color, which sheds some light on this color confusion.

Gene variant responsible for cinnamon morph black bear

Emily Puckett, PhD, an Assistant Professor of Biological Sciences at the University of Memphis, has devoted her career to learning more about the evolution and genetics of bears. With help from partners in state, provincial, and federal wildlife agencies, she collected hundreds of DNA and hair samples from North American bears. She teamed up with Greg Barsh, MD, PhD, Faculty Investigator at HudsonAlpha, and animal pigmentation expert to figure out why black bears aren’t always black.

In mammals, pigment is produced by skin cells called melanocytes. There are two types of melanin: eumelanin is black or brown, and pheomelanin is red or yellow. It is widely accepted that genetic variation in melanin biosynthesis gives rise to differences in hair, eye, and skin color. By studying photos of bears and chemically analyzing their corresponding hair samples, the team determined that cinnamon-colored black bears have reduced amounts of eumelanin, just like grizzly bears. 

Genome sequence analysis of nearly 200 bears uncovered different missense mutations in the gene Tyrosinase-related protein 1 (TYRP1): cinnamon-colored black bears have a mutation called TYRP1R153C, while most (but not all) grizzly bears have a mutation called TYRP1R114C. The TYRP1 gene produces an enzyme within melanocytes that helps produce eumelanin, so it makes sense that the cinnamon and grizzly bears have less eumelanin. Furthermore, functional studies carried out by Mickey Marks, PhD, Professor of Pathology at the University of Pennsylvania, and his lab, determined that the TYRP1R153C and TYRP1R114C mutations interfere with melanin synthesis and distribution.

“When we looked at other species, we were surprised to find the TYRP1R153C variant responsible for cinnamon U. americanus is identical to one previously described as a cause of oculocutaneous albinism (OCA3) in humans,” says Barsh. OCA3 is characterized by reddish skin and hair and frequent visual abnormalities and is most common in people of African or Puerto Rican ancestry. But according to Puckett, bears with TYRP1 mutations have normal skin and can see just fine.

When and where did the cinnamon morph arise?

The TYRP1R153C variant was primarily found in the southwest United States, at lower frequencies moving northward to Southeast Alaska and the Yukon Territory. TYRP1R153C was associated with the cinnamon color in black bears and the chocolate and light brown colors, meaning it accounts for almost all of the color diversity among U. americanus.

The researchers used their data to learn more about the TYRP1R153C mutation. One hypothesis is that it may have started in grizzly bears and then was transferred to black bears, but demographic analysis indicated that was not the case. Instead, the TYRP1R153C mutation arose spontaneously about 9,360 years ago in black bears living in the western United States, then spread as the bears moved across their current geographic range.

“Based on its wide range today, the TYRP1R153C mutation that arose in black bears over 9,000 years ago probably gave an advantage to the cinnamon bears,” says Puckett. “We used genetic modeling and simulations to predict the selective forces acting on the cinnamon morph. But our predictions ruled out the grizzly mimicry hypothesis as well as another hypothesis having to do with thermoregulation.”

As to why the coat color variant arose in the first place, the team presents a new hypothesis: crypsis. Crypsis refers to the ability of an animal to conceal itself and blend into the environment. Generally, crypsis is found in prey species and ambush predators who color match within their environments. Here, the researchers suggest crypsis as a broader adaptive mechanism for large-bodied species.

“These results illustrate how genetic variation in melanin biosynthesis can underlie iconic phenotypes and inform our understanding of color variation and recent evolution in large carnivores,” says Barsh.

By: Sarah Sharman, PhD, Science writer

Climate change played key role in dinosaur success story


Peer-Reviewed Publication

UNIVERSITY OF BIRMINGHAM

Life in the Chañares formation 

IMAGE: DINOSAUR ANCESTORS ARE SHOWN IN THIS ARTIST'S CONCEPTION OF LIFE IN THE CHAÑARES FORMATION APPROXIMATELY 235 MILLION YEARS AGO view more 

CREDIT: VICTOR O. LESHYK, WWW.PALEOVISTA.COM

Climate change, rather than competition, played a key role in the ascendancy of dinosaurs through the Late Triassic and Early Jurassic periods.

According to new research, changes in global climate associated with the Triassic-Jurassic mass extinction – which wiped out many large terrestrial vertebrates such as the giant armadillo-like aetosaurs – actually benefitted the earliest dinosaurs.

In particular, sauropod-like dinosaurs, which became the giant herbivore species of the later Jurassic like Diplodocus and Brachiosaurus, were able to thrive and expand across new territories as the planet warmed up after the extinction event, 201 million years ago.

The new evidence is published in Current Biology, by an international team of palaeontologists led by the Universities of Birmingham and Bristol, in the UK, Friedrich-Alexander University Erlangen-Nürnberg (FAU), in Germany, and the University of São Paulo in Brazil.

The team compared computer models of prehistoric global climate conditions such as temperature and rainfall with data on the different locations of dinosaurs taken from sources such as the Paleobiology Database. They showed how the sauropods, and sauropod-like animals, with their long tails and necks and small heads, were the runaway success story of a turbulent period of evolution.

Dr Emma Dunne, now a lecturer in palaeontology at FAU, carried out the research while at the University of Birmingham. She said: “What we see in the data suggests that instead of dinosaurs being outcompeted by other large vertebrates, it was variations in climate conditions that were restricting their diversity. But once these conditions changed across the Triassic-Jurassic boundary, they were able to flourish.

“The results were somewhat surprising, because it turns out that sauropods were really fussy from the get-go: later in their evolution they continue to stay in warmer areas and avoid polar regions.”

Co-author on the paper, Professor Richard Butler, at the University of Birmingham, said: “Climate change appears to have been really important in driving the evolution of early dinosaurs. What we want to do next is use the same techniques to understand the role of climate in the next 120 million years of the dinosaur story”.

The research was funded by the Leverhulme Trust and the European Research Council.

Construction starts of innovative research vessel RV Anna Weber-van Bosse

New ship prepared for new fuel and able to work close to sea ice

Business Announcement

ROYAL NETHERLANDS INSTITUTE FOR SEA RESEARCH

Milestone: representatives of NWO, NIOZ and Spanish shipbuilder Astilleros Armon sign the contract. 

IMAGE: MILESTONE: REPRESENTATIVES OF NWO (MARCEL LEVI), NIOZ (HAN DOLMAN) AND SPANISH SHIPBUILDER ASTILLEROS ARMON (LAUDELINO ALPERI BARAGANO) SIGN THE CONTRACT. PHOTO: EVALIEN WETERINGS. view more 

CREDIT: EVALIEN WETERINGS

Future-proof
“Compared to the current RV Pelagia, the RV Anna Weber-van Bosse will be equipped with much larger laboratories, more accommodations and more modern equipment”, says Han Dolman, Director of NIOZ.  “As we’re increasingly aware that the seas and oceans are fundamental to the natural systems on earth – systems that give us our food, energy and raw materials and that regulate our climate – it is vital for us to better understand trends and potential tipping points in marine processes. That knowledge will serve as a foundation for the sustainable use of oceans, and for climate adaptation and mitigation. This would not be possible without a modern research vessel.”

Technical specifications of the RV Anna Weber-van Bosse.

National marine research
The RV Anna Weber-van Bosse will be the largest new vessel in the national research fleet, and will be available in two years to all of the Netherlands’ marine researchers. The research fleet consists of three vessels managed by the National Marine Facilities (NMF) department of the NIOZ, which is part of the Dutch Research Council (NWO).

Marcel Levi, chair of the NWO Board, has this to say about the future vessel: “With the arrival of the ocean-going RV Anna Weber-van Bosse, the high-quality Dutch marine research community will have a modern, sustainable research vessel for many decades to come. The vessel, the crew and the facilitating organisations NIOZ and NMF offer the entire Dutch marine science community the facilities that are essential for oceanic research.”

NWO recently approved the definitive grant of the contract for this project to Spanish shipbuilder Astilleros Armon, which had emerged as the best option from the obligatory European tender based on price, technical specifications, sustainability, action plan, project organisation and innovation. Astilleros Armon is the party that best complements the Technical Specifications, which include a detailed inventory of all of the scientific, technical and functional requirements of all of the potential Dutch stakeholders, including the NMF and the crew of the RV Pelagia.


Artist impression of the new RV Anna Weber-van Bosse. Image: NIOZ.

CREDIT

NIOZ

A lot of experience with building research vessels
This isn’t Astilleros Armon’s first experience with the construction of research vessels. The shipyard recently delivered the RV Tom Crean to the Irish Marine Institute. Laudelino Alperi Baragano, CEO-owner of Astilleros Armon:  “The Irish vessel is indeed the 10th research vessel delivered by Armon in the past 10 years and we are currently  building other research vessels for New Zealand, Iceland and an Antarctic Polar research vessel for Spain. All of these vessels consolidate Armon as world leader in the design and fabrication of Research Vessels."

Named after female marine biologist
The flagship of the Dutch research fleet will be named after Anna Weber-van Bosse, the Netherlands’ first female marine biologist to conduct research at sea. At the turn of the 20th century, she made substantial contributions to the development of the marine sciences in the Netherlands, as indicated by her many publications, enormous algae collection and honourary doctorate from Utrecht University. One of her contributions was the report on her research into chalkweed and algae as a member of the Siboga expedition to the Dutch East Indies in 1899-1900. Read more about it in her biography.

Warm days are contributing to gun violence surge across the US

For the first time, a study has linked hotter days to an increased risk of shootings in the nation’s 100 largest cities.

Peer-Reviewed Publication

BOSTON UNIVERSITY SCHOOL OF PUBLIC HEALTH

From Philadelphia to Portland, cities across the United States are experiencing spikes in gun violence on warm days. Researchers have begun to explore heat as a contributor to firearm violence, but current research on this subject is limited, focusing only on a few cities.

Now, a new study by Boston University School of Public Health and the University of Washington School of Social Work provides a first-of-its-kind analysis of heat-attributable shootings as a nationwide problem.

Published in the journal JAMA Network Open, the study found a consistent relationship between higher temperatures and higher risk of shootings in 100 of the country’s most populated cities.

The comprehensive study reveals that nearly seven percent of shootings can be attributed to above-average daily temperatures, even after adjusting for seasonal patterns. The findings indicate that the Northeast and Midwest regions experience the sharpest increases in gun violence on hotter-than-normal days.

“Our study provides strong evidence that daily temperature plays a meaningful role in gun violence fluctuations,” says study senior author Dr. Jonathan Jay, assistant professor of community health sciences at BUSPH, director of BUSPH’s Research on Innovations for Safety and Equity (RISE) Lab, and a partnering faculty member of Boston University’s Center for Climate and Health (BU CCH). “Even though some regions showed larger or smaller effects, the general pattern is remarkably consistent across cities.”

Gun violence is the leading cause of death among children and teens, and this violence has worsened substantially during the pandemic. As climate change threatens to raise daily temperatures even more, the researchers say these findings underscore the need for ongoing policies and programs that acclimate communities to heat and mitigate the risk of heat-attributable gun violence.

“Our study really highlights the importance of heat adaptation strategies that can be used all year, as well as a need for specific regional awareness and attention in regions where this relationship is strongest,” says study lead author Dr. Vivian Lyons, a research scientist in the Social Development Research Group at the University of Washington’s School of Social Work, and who began the study as a postdoctoral fellow with the Firearm-safety Among Children & Teens (FACTS) Consortium at the University of Michigan.

For the study, Dr. Jay, Dr. Lyons, and colleagues utilized publicly available data from the Gun Violence Archive, a national repository of gun violence information. The team analyzed daily temperatures and more than 116,000 shootings from 2015 to 2020, in the top 100 US cities with the highest number of assault-related shootings in the country. Accounting for seasonality and regional climate differences, they found that 7,973 shootings were attributable to above-average temperatures. The temperatures associated with increased gun violence varied considerably across cities. For example, both Seattle and Las Vegas experienced the highest elevated risk of gun violence during days when the temperature soared within the 96th percentile range of average daily temperatures—but for Seattle, that temperature was 84 degrees, while in Las Vegas, it was 104 degrees. 

“Cities with high rates of firearm violence should continue to implement firearm-prevention strategies broadly including credible messenger programs and hospital-based violence intervention programs,” Dr. Lyons says. “What our study suggests is that for cities with more heat-attributable shootings, implementing heat adaptation strategies at the community level—such as greening efforts that have been effective at reducing urban heat islands and have some association with reductions in firearm violence—may be particularly important.”

So what might be driving this association between heat and gun violence? “It could be that heat causes stress, which makes people more likely to use aggression,” Dr. Jay says. “Or it could be that people are more likely to get out on warmer days and have more interactions, which creates more opportunities for conflict and violence. Most likely, it’s a combination of both.”

Regionally, heat-attributable gun violence may be most pronounced in the Northeast and Midwest due to sharper fluctuations in temperature in those areas, even within seasons, or because cities in those regions are less acclimated to heat, the researchers say. But those regions are also more racially segregated than other areas of the country. The study findings should be interpreted within the context of structural racism and racial inequities in exposure to gun violence and heat, says Dr. Jay.

“The Northeast and Midwest regions are where we see some of the starkest differences in the built environment and other resources, according to race—to me, these inequities are the most interesting and important direction of this work,” Dr. Jay says. “We know that segregation and disinvestment lead communities of color, especially Black communities, to have greater exposure to adverse environmental conditions that contribute to gun violence risk, such as abandoned buildings, liquor stores, lack of green space, and more intense urban heat islands.”

Healthy tree canopy and other heat mitigation strategies can serve as part of a mission that’s “part racial justice, part climate change mitigation, and part gun violence prevention,” he says. “These are all urgent issues where we need to continue to partner with communities and work across disciplines.”

The researchers will next study differences in heat-related gun violence among neighborhoods, in a project funded by the National Collaborative on Gun Violence Research and led by Dr. Zihan Lin, a postdoctoral associate in the Department of Community Health Sciences at BUSPH and a researcher for BU CCH.

"This study extends our understanding of the many health harms associated with extreme heat,” says Dr. Gregory Wellenius, professor of environmental health and director of BU CCH. “I'm pleased that the new BU Center for Climate and Health can support this work as part of our commitment to research to reduce the health impacts of continued climate change."

The study was coauthored by Emma Gause, research scientist in the Department of Environmental Health (EH) at BUSPH, and Keith Spangler, research scientist in EH and the Biostatistics and Epidemiology Data Analytics Center (BEDAC) at BUSPH.

**

About Boston University School of Public Health
Founded in 1976, 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.

Physician, heal thyself?

Research shows doctors and their families are less likely to follow guidelines about medicine. Why do the medically well-informed comply less often?

Peer-Reviewed Publication

MASSACHUSETTS INSTITUTE OF TECHNOLOGY

Following established guidelines about prescription drugs would seem to be an obvious course of action, especially for the professionals that do the prescribing. Yet doctors and their family members are less likely than other people to comply with those guidelines, according to a large-scale study co-authored by an MIT economist.

Depending on your perspective, that result might seem surprising or it might produce a knowing nod. Either way, the result is contrary to past scholarly hypotheses. Many experts have surmised that knowing more, and having easier communication with medical providers, leads patients to follow instructions more closely.

The new study is based on over a decade of population-wide data from Sweden and includes suggestive evidence about why doctors and their families may ignore medical advice. Overall, the research shows that the rest of the population adheres to general medication guidelines 54.4 percent of the time, while doctors and their families lag 3.8 percentage points behind that.

“There’s a lot of concern that people don’t understand guidelines, that they’re too complex to follow, that people don’t trust their doctors,” says Amy Finkelstein, a professor in MIT’s Department of Economics. “If that’s the case, you should see the most adherence when you look at patients who are physicians or their close relatives. We were struck to find that the opposite holds, that physicians and their close relatives are less likely to adhere to their own medication guidelines.”

The paper, “A Taste of Their Own Medicine: Guideline Adherence and Access to Expertise,” is published this month in the American Economic Review: Insights. The authors are Finkelstein, the John and Jennie S. MacDonald Professor of Economics at MIT; Petra Persson, an assistant professor of economics at Stanford University; Maria Polyakova PhD ’14, an assistant professor of health policy at the Stanford University School of Medicine; and Jesse M. Shapiro, the George Gund Professor of Economics and Business Administration at Harvard University.

Millions of data points

To conduct the study, the scholars examined Swedish administrative data from 2005 through 2016, as applied to 63 prescription drug guidelines. The data enabled the researchers to determine who is a doctor; the study largely defined close relatives as partners, parents, and children. All told, the research involved 5,887,471 people to whom at least one of the medication guidelines applied. Of these people, 149,399 were doctors or their close family members.

Using information on prescription drug purchases, hospital visits, and diagnoses, the researchers could see if people were adhering to medication guidelines by examining whether prescription drug decisions matched these patients’ medical circumstances. In the study, six guidelines pertained to antibiotics; 20 involved medication use by the elderly; 20 focused on medication attached to particular diagnoses; and 17 were about prescription drug use during pregnancy.

Some guidelines recommended use of a particular prescription drug, like a preference of narrow-spectrum antibiotics for an infection; other guidelines were about not taking certain medications, such as the recommendation that pregnant women avoid antidepressants.

Out of the 63 guidelines used in the study, doctors and their families followed the standards less often in 41 cases, with the difference being statistically significant 20 times. Doctors and their families followed the guidelines more often in 22 cases, with the difference being statistically significant only three times.

“What we found, which is quite surprising, is that they [physicians] are on average less adherent to guidelines,” says Polyakova, who received her PhD from MIT’s Department of Economics. “So, in this paper we are also trying to figure out what experts do differently.”

Ruling out other answers

Since doctors and their close relatives adhere to medical guidelines less often than the rest of the population, what exactly explains this phenomenon? While homing in on an answer, the research team examined and rejected several hypotheses.

First, the lower compliance by those with greater access to expertise is unrelated to socioeconomic status. In society overall, there is a link between income and adherence levels, but physicians and their families are an exception to this pattern. As the scholars write in the paper, special “access to doctors is associated with lower adherence despite, rather than because of, the high socioeconomic status” of those families.

Additionally, the researchers did not find any link between existing health status and adherence. They also studied whether a greater comfort with prescription medication — due to being a doctor or related to one — makes people more likely to take prescription drugs than guidelines recommend. This does not appear to be the case. The lower adherence rates for doctors and their relatives were similar in magnitude whether the guidelines pertained to taking medication or, alternately, not taking medication.

“There are a number of first-order alternative explanations that we could rule out,” Polyakova says.

Resolving a medical mystery

Instead, the researchers believe the answer is that doctors possess “superior information about guidelines” for prescription drugs — and then deploy that information for themselves. In the study, the difference in adherence to guidelines between experts and nonexperts is largest in the case of antibiotics: Doctors and their families are 5.2 percentage points less in compliance than everyone else.

Most guidelines in this area recommend starting patients off with “narrow-spectrum” antibiotics, which are more targeted, rather than “broader-spectrum” antibiotics. The latter might be more likely to eradicate an infection, but greater use of them also increases the chances that bacteria will develop resistance to these valuable medications, which can reduce efficacy for other patients. Thus for things like a respiratory tract infection, guidelines call for a more targeted antibiotic first.

The issue, however, is that what is good for the public in the long run — trying more targeted drugs first — may not work well for an individual patient. For this reason, doctors could be more likely to prescribe broader-spectrum antibiotics for themselves and their families.

“From a public-health perspective, what you want to do is kill it [the infection] off with the narrow-spectrum antibiotic,” Finkelstein observes. “But obviously any given patient would want to knock that infection out as quickly as possible.” Therefore, she adds, “You can imagine the reason doctors are less likely to follow the guidelines than other patients is because they … know there’s this wedge between what’s good for them as a patients and what’s good for society.”

Another suggestive piece of data comes from different types of prescription drugs that are typically avoided during pregnancies. For so-called C-Class drugs, where empirical evidence about the dangers of the drugs is slightly weaker, doctors and their families have an adherence rate 2.3 percentage points below other people (meaning, in this case, that they are more likely to take these medications during pregnancy). For so-called D-Class drugs with slightly stronger evidence of side effects, that dropoff is only 1.2 percentage points. Here too, doctors’ expert knowledge may be influencing their actions.

“The results imply that probably what’s going on is that experts have a more nuanced understanding of what is the right course of action for themselves, and how that might be different than what the guidelines suggest,” Polyakova says.

Still, the findings suggest some unresolved tensions in action. It could be, as Polyakova suggests, that guidelines about antibiotics should be more explicit about the public and private tradeoffs involved, providing more transparency for patients. “Maybe it’s better for the guidelines to be transparent and say they recommend this not because it is [always] the best course of action for you, but because it is the best for society,” she says.

Additional research could also aim to identify areas where lower expert adherence with guidelines may be associated with better health outcomes — to see how often doctors have a point, as it were. Or, as the researchers write in the paper, “An important avenue for further research is to identify whether and when nonadherence is in the patient’s best interest.”

The research was supported, in part, by the Population Studies and Training Center and the Eastman Professorship at Brown University, and the National Institute on Aging.

Written by Peter Dizikes, MIT News Office

Additional background

Paper: “A Taste of Their Own Medicine: Guideline Adherence and Access to Expertise”

https://www.aeaweb.org/articles?id=10.1257/aeri.20210591

 

The AVID college prep program leads to lower substance use, better health behaviors among high school students, UCLA-led research suggests


The findings suggest that “academic tracking,” the practice of separating high and low performing students into different classes, reinforces risky social networks and behaviors


Peer-Reviewed Publication

UNIVERSITY OF CALIFORNIA - LOS ANGELES HEALTH SCIENCES

New UCLA-led research finds that a college preparatory program for youth experiencing educational inequities that operates in about 13% of U.S public high schools has a positive effect on students’ social networks, psycho-social outcomes, and health behaviors. 

The findings, published Dec. 16 in the peer-reviewed journal Pediatrics, suggests that the Advancement via Individual Determination (AVID) program, aimed at increasing educational opportunities for under-represented and economically disadvantaged students, also significantly reduces substance use.

“Academic tracking” is a common practice in high schools through which lower-performing students are clustered with others of similar academic achievement. Although intended to tailor academic rigor to students’ level of preparation, the study findings suggest that this practice may be counterproductive by reinforcing risky behaviors that students pick up from their peers.

“Untracking” these students by mixing them in with higher-performing peers may lead to better physical and psychological health, said lead author Dr. Rebecca Dudovitz, associate professor of pediatrics and director of pediatric health services research at the David Geffen School of Medicine at UCLA.

“This is the first randomized controlled trial of AVID in the United States, so it’s really exciting to see that this program that was designed to help open up educational opportunities for kids, also improved their health,” Dudovitz said.

AVID works with high school students earning B or C grade averages who might not otherwise be placed in more rigorous college preparatory tracks. It operates in 5,400 secondary schools, including both middle and high school, in 46 states and exposes academically middling students to tougher courses than they would have been assigned to under normal circumstances. AVID helps students develop agency, relational capacity, and opportunity knowledge.

“We believe that surrounding students with a supportive community and providing them with the skills and resources they need to reach their goals within existing educational structures is how we make college and career readiness possible for every student,” said Thuan Nguyen, AVID’s CEO. “The findings of the UCLA study are not surprising because AVID educators invest so much in their students’ lives.”

The researchers randomized 270 students in five large public schools who were placed in either an AVID group or in usual school programs. Students completed surveys at the end of 8th grade or beginning of 9th grade, and again at the end of 9th grade.

They found that students in the AVID group had lower odds of using substances--a 33% reduced risk compared to the control group--in addition to a 26% lower risk of associating with substance-using peers and about 1.7 times the odds of socializing with peers who were more involved with academics.

In addition, AVID males experienced lower stress and higher self-efficacy, determination and engagement with school than their peers who were assigned to the usual tracked academic program. These effects, however, were not seen among females, possibly because supportive academic environment have a greater effect on boys of color, the researchers write.

“AVID positively impacts social networks, health behaviors, and psycho-social outcomes suggesting academic untracking may have substantial beneficial spillover effects on adolescent health,” the researchers write.

The study has some limitations. The schools were all from a single school district and primarily serve low-income Latino students, and the findings were all from one school year, the researchers note. They did not directly observe how AVID was implemented or examine if the program actually increased college enrollment. In addition, it was not possible to blind the participants, meaning that students knew who was assigned to each group, which could have led them to respond to survey questions in ways that they thought the researchers would view favorably.

While more research is needed, the findings still provide important evidence that “ensuring schools have the resources and structures necessary to expand access to educational opportunities and facilitate healthy social connections, particularly in marginalized communities, may be key to achieving education and health equity more broadly,” the researchers write.

The Robert Wood Johnson Foundation Evidence for Action Program (Grant 74086) and National Institutes of Health (1K23DA040733-01A1) funded this research.

Study co-authors are Dr. Paul Chung, Kulwant Dosanjh, Meredith Phillips, Christopher Biely, Chi-Hong Tseng, and Dr. Mitchell Wong of UCLA; Joan Tucker of RAND Corporation; Mary Ann Pentz of USC; and Arzie Galvez and Guadalupe Arellano of Los Angeles Unified School District. Chung is also affiliated with Kaiser Permanente.

 

FOR PROFIT HEALTHCARE U$A

Cost concerns keep older adults from seeking emergency care

People in their pre-Medicare years, especially those who are uninsured or have low incomes, are most likely to skip a trip to the ER because of what they might have to pay

Peer-Reviewed Publication

MICHIGAN MEDICINE - UNIVERSITY OF MICHIGAN

Worries about what emergency care might cost them have kept some older adults from seeking medical attention even when they felt they might need it, a new study shows.

In all, 22% of older adults who may have needed care from the emergency department didn’t go because of concerns about what they might have to pay, according to the new findings published in the American Journal of Managed Care.

People in their 50s and early 60s, women, those who lack health insurance, people with household incomes under $30,000, and those who say their mental health is fair or poor were most likely to say they’d avoided getting emergency care because of cost concerns.

The study, based on a survey conducted in June 2020, asked older adults to think back on the previous two years, including the first months of the COVID-19 pandemic.

Even among those who hadn’t had a medical emergency in this time, worries about what an emergency visit might cost them were high. Four out of five older adults said they were concerned about the cost of emergency care (35% somewhat concerned and 45% very concerned, and 18% were not confident they could afford a visit.

The data from the study come from the National Poll on Healthy Aging, based at the University of Michigan Institute for Healthcare Policy and Innovation and supported by AARP and Michigan Medicine, U-M’s academic medical center. The findings build on the poll report published earlier and are based on responses from a nationally representative sample of 2,074 people age 50 to 80.

The findings confirm the experience of lead author Rachel Solnick, M.D., M.Sc., who trained in IHPI’s National Clinician Scholars Program before joining the faculty at the Icahn School of Medicine at Mount Sinai Health System in New York.

“As an emergency physician, I have seen patients come to the emergency room having postponed their care. They often come in sicker than they would have been had they received care sooner,” she said. “That scenario is what I find most alarming in this survey’s findings. Some groups that are medically vulnerable or have suffered worse outcomes from COVID-19 were more likely to report cost-related avoidance of the ER than their counterparts. These findings highlight the importance of reducing the number of uninsured individuals and the need for insurers to clearly communicate coverage for emergency services.”

Keith Kocher, M.D., the study’s senior author and an associate professor of emergency medicine at U-M, notes that the federal No Surprises Act was enacted after the study was done. That act seeks to reduce “surprise billing” for emergency care when a privately insured person receives it from hospitals or providers outside their health insurance plan’s network. At the time of the study, Medicare and Medicaid already prohibited emergency care providers from doing this kind of “balance billing.”

Even so, a person with private insurance might owe hundreds of dollars in co-pays or deductibles for an emergency visit, the authors note. That’s especially true for people with high-deductible health plans, which are growing in enrollment.

Even though the percentage of older adults who lack any health insurance is small (4% of the study sample), they were 35% more likely to say they were not confident they could afford emergency care. Solnick notes that both the pandemic’s economic impacts, and the decision by more than a dozen states including Texas and Florida to not expand Medicaid to all low-income adults, mean that millions of people may face paying out of pocket for emergency visits.

American Journal of Managed Care, 2023;29(4): In Press, https://www.ajmc.com/view/older-adults-perspectives-on-emergency-department-costs-during-covid-19

Scientists discover what was on the menu of the first dinosaurs


Peer-Reviewed Publication

UNIVERSITY OF BRISTOL

Fig 1 

IMAGE: THE THREE MAIN DINOSAUR LINEAGES AND THEIR TYPICAL TOOTH SHAPES view more 

CREDIT: ANTONIO BALLELL

The earliest dinosaurs included carnivorous, omnivorous and herbivorous species, according to a team of University of Bristol palaeobiologists.

By looking at the tooth shapes of the earliest dinosaurs and simulating their tooth function with computational modelling, experts were able to compare them to living reptiles and their diets. Their findings, published today in Science Advances, show that many groups of plant-eating dinosaurs were ancestrally omnivorous and that the ancestors of our famous long-necked herbivores, such as Diplodocus, ate meat. This ability to diversify their diets early in their evolution likely explains their evolutionary and ecological success.

The earliest dinosaurs are enigmatic: they were much smaller than their later relatives and for most of the Triassic they were in the shadow of the crocodile-like reptiles. It is unknown how diverse they were in terms of diets and ecology, but scientists know something must have happened in the Triassic that allowed dinosaurs to endure the Triassic–Jurassic mass extinction and adapt in its aftermath, becoming the dominant group for the rest of the Mesozoic.

Lead author Dr. Antonio Ballell from the University of Bristol said “Soon after their origin, dinosaurs start to show an interesting diversity of skull and tooth shapes. For decades, this has made palaeontologists suspect that different species were already experimenting with different kinds of diets. They have compared them to modern lizard species and tried to infer what they ate based on the similarities in their teeth.

“We investigated this by applying a set of computational methods to quantify the shape and function of the teeth of early dinosaurs and compare them to living reptiles that have different diets. This included mathematically modelling their tooth shapes and simulating their mechanical responses to biting forces with engineering software.”

Professor Mike Benton, co-author of the study, said: “With this battery of methods, we were able to numerically quantify how similar early dinosaurs were to modern animals, providing solid evidence for our inferences of diets. Theropod dinosaurs have pointy, curved and blade-like teeth with tiny serrations, which behaved like those of modern monitor lizards. In contrast, the denticulated teeth of ornithischians and sauropodomorphs are more similar to modern omnivores and herbivores, like iguanas.”

The study is also innovative in using machine learning models to classify the earliest dinosaurs in different diet categories based on their tooth shape and mechanics. For instance, Thecodontosaurus, the Bristol dinosaur, had teeth well adapted for a diet of plants.

Professor Emily Rayfield, senior co-author, said: “Our analyses reveal that ornithischians – the group that includes many plant-eating species like the horned dinosaurs, the armoured ankylosaurs and the duck-billed dinosaurs – started off as omnivores. And another interesting finding is that the earliest sauropodomorphs, ancestors of the veggie long-necked sauropods like Diplodocus, were carnivores. This shows that herbivory was not ancestral for any of these two lineages, countering traditional hypotheses, and that the diets of early dinosaurs were quite diverse.”

Dr. Ballell concluded: “It seems that one of the things that made the first dinosaurs special is that they evolved different diets throughout the Triassic, and we think this might have been key for their evolutionary and ecological success.”

Dinosaurs dominated the land during the Mesozoic era until their extinction 66 million years ago. They included giant veggie groups like the long-necked sauropods and meat-eating species like Tyrannosaurus rex and its relatives. However, their origins were much humbler and date back to the Triassic period, with the first definitive dinosaurs appearing approximately 235 million years ago.

Paper:

‘Dental form and function in the early feeding diversification of dinosaurs’ by Antonio Ballell, Michael J. Benton and Emily J. Rayfield in Science Advances.

DOI: 10.1126/sciadv.abq5201