Serving larger portions of veggies may increase young kids' veggie consumption

PENN STATE

Research News

 

UNIVERSITY PARK, Pa. -- It can be difficult to get young kids to eat enough vegetables, but a new Penn State study found that simply adding more veggies to their plates resulted in children consuming more vegetables at the meal.

The researchers found that when they doubled the amount of corn and broccoli served at a meal -- from 60 to 120 grams -- the children ate 68% more of the veggies, or an additional 21 grams. Seasoning the vegetables with butter and salt, however, did not affect consumption.

The daily recommended amount of vegetables for kids is about 1.5 cups a day, according to the official Dietary Guidelines for Americans as set by the U.S. Departments of Agriculture and Health and Human Services.

"The increase we observed is equal to about one third of a serving or 12% of the daily recommended intake for young children," said Hanim Diktas, graduate student in nutritional sciences. "Using this strategy may be useful to parents, caregivers and teachers who are trying to encourage kids to eat the recommended amount of vegetables throughout the day."

Barbara Rolls, Helen A. Guthrie Chair and director of the Laboratory for the Study of Human Ingestive Behavior at Penn State, said the findings -- recently published in the journal Appetite -- support the MyPlate guidance from the U.S. Department of Agriculture, which recommends meals high in fruits and vegetables.

"It's important to serve your kids a lot of vegetables, but it's also important to serve them ones they like because they have to compete with the other foods on the plate," Rolls said. "Parents can ease into this by gradually exposing kids to new vegetables, cooking them in a way their child enjoys, and experimenting with different flavors and seasonings as you familiarize them."

According to the researchers, the majority of children in the U.S. don't eat the recommended daily amount of vegetables, which could possibly be explained by children having a low preference for them. And while serving larger portions has been found to increase the amount of food children eat -- called the "portion size effect" -- kids tend to eat smaller amounts of vegetables in response to bigger portions compared to other foods.

For this study, the researchers were curious if increasing just the amount of vegetables while keeping the portions of other foods the same would help increase veggie consumption in kids. They also wanted to experiment with whether adding light butter and salt to the vegetables would increase their palatability and also affect consumption.

For the study, the researchers recruited 67 children between the ages of three and five. Once a week for four weeks, the participants were served lunch with one of four different preparations of vegetables: a regular-sized serving of plain corn and broccoli, a regular-sized serving with added butter and salt, a doubled serving of plain corn and broccoli, and a doubled serving with added butter and salt.

During each meal, the vegetables were served alongside fish sticks, rice, applesauce and milk. Foods were weighed before and after the meal to measure consumption.

"We chose foods that were generally well-liked but also not the kids' favorite foods," Rolls said. "If you offer vegetables alongside, say, chicken nuggets you might be disappointed. Food pairings are something you need to be conscious of, because how palpable the vegetables are compared to the other foods on the plate is going to affect the response to portion size. You need to make sure your vegetables taste pretty good compared to the other foods."

After analyzing the results, the researchers found that while the larger portions of vegetables were associated with greater intake, the addition of butter and salt was not. The children also reported liking both versions -- seasoned and unseasoned -- about the same. About 76% of kids rated the vegetables as "yummy" or "just ok."

"We were surprised that the butter and salt weren't needed to improve intake, but the vegetables we served were corn and broccoli, which may have been already familiar to and well-liked by the kids," Diktas said. "So for less familiar vegetables, it's possible some extra flavoring might help to increase intake."

Diktas said that while serving larger portions may increase vegetable consumption, it also has the potential to increase waste if kids don't eat all of the food that is served.

"We're working on additional research that looks into substituting vegetables for other food instead of just adding more vegetables," Diktas said. "In the future, we may be able to give recommendations about portion size and substituting vegetables for other foods, so we can both limit waste and promote veggie intake in children."

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Liane Roe, research nutritionist; Kathleen Keller, associate professor of nutritional sciences; and Christine Sanchez, lab manager at the Laboratory for the Study of Human Ingestive Behavior, also participated in this work.

The National Institute of Diabetes Digestive and Kidney Diseases helped support this research.

 

Real cheese, no animals - More than 70% of consumers want breakthrough cheese

University of Bath press release

UNIVERSITY OF BATH

Research News

 

Berlin and Bath, 24th June 2021 - Precision-fermentation company Formo and the University of Bath co-published the first large-scale study of consumer acceptance for animal-free dairy products.

Researchers surveyed 5,054 individuals from Brazil, Germany, India, the UK, and the USA to understand what consumers think of animal-free dairy products.

Precision fermentation is a process that allows specific proteins to be produced via microorganisms. By inserting a copied stretch of cow DNA, microorganisms produce milk proteins. The process is more efficient than using animals to make proteins and avoids the negative side effects of industrial animal agriculture, which is responsible for 18% of all greenhouse gas emissions.

The findings of the study, published in the journal Frontiers in Sustainable Food Systems, show that consumers around the world are ready for cheese made from real milk proteins produced by microorganisms.

Across countries and age groups, 79% of consumers are willing to try precision-fermentation-derived dairy cheese, with 71% willing to pay for such products. Across dietary preferences, flexitarians showed the highest levels of enthusiasm for these products.

"Just as we have seen plant-based milk taking an increasing share of the milk market in recent years, we now see that consumers are ready for a new kind of animal-free dairy cheese product." Christopher Bryant, PhD, of the University of Bath, said.

"Seeing the growing consumer groups of flexitarians and young people driving adoption of animal-free cheese is a big indicator that these products will appeal to consumers far beyond the niche markets of current vegan cheese."

Findings highlighted that consumers understood the big taste improvements over current vegan cheese products, while also showing that consumers across countries recognised the environmental and ethical advantages of animal-free dairy, which causes 85-97% less greenhouse gas emissions than conventional dairy.

"Most cheese lovers think current vegan cheeses are nowhere near the flavour or functionality level that meets their cheese needs." said Oscar Zollman Thomas, Formo's lead researcher on the project.

"Precision fermentation is allowing us to fundamentally change that and make real cheese without animals involved."

This was reflected in another major finding of the research, that those who currently eat the most cheese were the most likely to want to buy animal-free dairy cheese.

"That finding was explosive because that's always how we've understood the mission: Initiating change not through consumer sacrifice, but rather through delicious, satisfying products" said Oscar Zollman Thomas.

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Adolescent marijuana, alcohol use held steady during COVID-19 pandemic

NIH/NATIONAL INSTITUTE ON DRUG ABUSE

Research News

 

Adolescent marijuana use and binge drinking did not significantly change during the COVID-19 pandemic, despite record decreases in the substances' perceived availability, according to a survey of 12th graders in the United States. The study's findings, which appeared online on June 24, 2021, in Drug and Alcohol Dependence, challenge the idea that reducing adolescent use of drugs can be achieved solely by limiting their supply. The work was led by researchers at the University of Michigan, Ann Arbor, and funded by the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health.

In contrast to consistent rates of marijuana and alcohol use, nicotine vaping in high school seniors declined during the pandemic, along with declines in perceived availability of vaping devices at this time. The legal purchase age is 21 for nicotine products and alcohol in all states, and for cannabis in states that have legalized nonmedical cannabis use.

"Last year brought dramatic changes to adolescents' lives, as many teens remained home with parents and other family members full time," said NIDA Director Nora D. Volkow, M.D. "It is striking that despite this monumental shift and teens' perceived decreases in availability of marijuana and alcohol, usage rates held steady for these substances. This indicates that teens were able to obtain them despite barriers caused by the pandemic and despite not being of age to legally purchase them."

The data for the study came from the annual Monitoring the Future (MTF) survey of substance use behaviors and related attitudes among adolescents in the United States. In a typical year, MTF surveys thousands of middle and high school students at more than a hundred schools across the country in the spring. MTF has been watching substance use trends for 46 years.

To assess the impact of the pandemic, the investigators issued a survey between mid-July and mid-August 2020, which 12th graders could complete outside of school. This summer survey followed up on investigators' standard MTF spring survey, which gathered responses between mid-February and mid-March 2020 before stopping prematurely due to school closures caused by COVID-19. Of the 3,770 12th graders who responded in the spring, 582 submitted a follow-up survey in the summer. All data and statistical analyses used in the study were weighted to be nationally representative.

Analysis of the responses revealed that students perceived a sharp decrease in availability of marijuana and alcohol in the months after the onset of the pandemic. For marijuana, the fraction of students who reported "fairly" or "very" easy access dropped by 17 percentage points, from 76% in the spring before the pandemic to 59% during the pandemic, and for alcohol it dropped by 24 percentage points, from 86% to 62%. These were the largest year-to-year decreases in perceived availability of marijuana and alcohol ever recorded since the survey began in 1975. Prior to 2020, the largest recorded decreases were only two percentage points for marijuana, and one percentage point for alcohol. Between the spring and summer of 2020, there was also a sharp decrease in respondents who said they could "fairly" or "very" easily obtain a vaping device, going from 73% before the pandemic to 63% during the pandemic.

Despite the reported declines in marijuana and alcohol availability, the levels of use of these substances did not change significantly. Before the pandemic, 23% of students said they had used marijuana in the past 30 days, compared to 20% during the pandemic. For alcohol, 17% reported binge drinking in the past two weeks pre-pandemic, compared to 13% during the pandemic. However, there was a moderate and significant decrease in nicotine vaping - before the pandemic, 24% of respondents said they had vaped nicotine in the past 30 days, compared to 17% during the pandemic.

The study authors cite the wide availability of alcohol and marijuana, even during the pandemic, as a factor in the continued use of these substances. While pandemic-related restrictions limited social interactions, and even with record-breaking decreases in perceived availability among participants, most students said they still had access to marijuana and alcohol. In addition, the authors suggest that when the substances became less available, the students may have intensified their efforts to obtain them.

While a dip in the perceived supply of vaping devices may have contributed to the decline in nicotine vaping that occurred during the pandemic, there may have been other factors as well. The federal minimum age for tobacco product purchases, including vaping devices and liquids, rose from 18 to 21 years and went into effect in early 2020. News reports on vaping-induced lung injuries may have also had a chilling effect on usage.

"These findings suggest that reducing adolescent substance use through attempts to restrict supply alone would be a difficult undertaking," said Richard A. Miech, Ph.D., lead author of the paper and team lead of the Monitoring the Future study at the University of Michigan. "The best strategy is likely to be one that combines approaches to limit the supply of these substances with efforts to decrease demand, through educational and public health campaigns."

Monitoring the Future continues to survey respondents as they progress through adulthood, providing the researchers with the opportunity to explore the impact of the pandemic and the social changes it brought about on future substance use trends.

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Reference: Miech R, et al. Adolescent Drug Use Before and During U.S. National COVID-19 Social Distancing Policies. Drug and Alcohol Dependence. DOI: 10.1016/j.drugalcdep.2021.108822(2021)

About the National Institute on Drug Abuse (NIDA): NIDA is a component of the National Institutes of Health, U.S. Department of Health and Human Services. NIDA supports most of the world's research on the health aspects of drug use and addiction. The Institute carries out a large variety of programs to inform policy, improve practice, and advance addiction science. For more information about NIDA and its programs, visit http://www.nida.nih.gov.

About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.

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Study highlights natural history and conservation importance of Chinese mountain cat

Study highlights the evolutionary uniqueness and premier conservation importance of the elusive Chinese mountain cat

NOVA SOUTHEASTERN UNIVERSITY

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IMAGE: CHINESE MOUNTAIN CAT. view more 

CREDIT: SONG DAZHAO, CFCA

FORT LAUDERDALE/DAVIE, Fla. - We know that the domestic cat has distant relatives that roam the earth - lions, tigers, cheetahs and mountain lions. Less familiar are the 38 distinct species in the Family Felidae, many with strange names like pampas cat, kodkod and rusty spotted cat. The new field of genomics - the unravelling of DNA genomes of separate species - is resolving old conundrums and revealing new secrets across the history of evolutionarily related species among cats, dogs, bears and ourselves.

In the largest-ever study undertaken of Chinese cats, genetic detectives highlight the evolutionary uniqueness and premier conservation importance of the elusive Chinese mountain cat (Felis silvestris bieti), found only in the Tibetan plateau of China. Also called Chinese desert cat or Steppe cat, the Chinese mountain cat has a distinctive appearance of sand colored fur, with faint dark stripes a thick tail and light blue pupils.

The research is published in Science Advances.

This new study compared three different felines living in China: the Chinese mountain cat, Felis silvestris bieti, the Asiatic wildcat Felis silvestris ornata, and feral domestic cats Felis silvestris catus. The Asiatic wildcat has distinguishing spotted coat pattern across a wide range extending from the Caspian Sea in the East through western India and southern Mongolia to parts of western China. Approximately 600 million domestic cats are found across the world.

The study was led by the Laboratory of Genomic Diversity at Peking University in Beijing and supported by an international team including lead genetic researchers at Nova Southeastern University, USA and in Malaysia. The genomic data resolves a taxonomic classification uncertainty, reveals the timing of evolutionary divergence and pinpoints the prospects for survival of an important endangered species.

Using 270 individual samples, the molecular genetic study finds that the Chinese mountain cat is a unique subspecies of the wide-ranging Wildcat, Felis silvestris. The wildcat species is found throughout Europe, Africa, and much of Western Asia. The Felis silvestris bieti subspecies, however, is found only in China, being adapted to the prey and alpine climate of the Tibetan plateau.

Applying the molecular clock hypotheses, the date of evolutionary split between F. s. bieti and F. s. ornata was a estimated at ~1.5 million years ago while the genetic distance from both to the closest Felis species relative, the black footed cat, Felis nigripes is twice that at 3.0 MY ago. These different times support the classification of F. s. ornata and F. s. bieti as subspecies of Felis silvestris. A closely related subspecies from Central Asia and north Africa, Felis silvestris lybica , is the clear predecessor of the world's domestic cats, including those throughout China. The cat domestication process happened 10-12,000 years ago in the Near East at around the same time and locale, when humankind ancestors morphed from peripatetic hunter-gatherers to sedentary farmers in the Fertile Crescent region.

The Chinese mountain cat faces several major threats, one from modern agricultural practices that divert precious habitat. A second, more existential threat, is from interbreeding with domestic cats brought by the growing human population in the cat's limited habitat. And finally, climate change, that may be expanding the range of neighboring wildcats into the mountain cat's core homeland.

"This study will help conservation scientists to identify threats and decide the best ways to conserve this special cat in its native range," said Stephen J. O'Brien, Ph.D., a world-renowned geneticist and research scientist at NSU's Halmos College of Arts and Sciences.

The study solidifies the taxonomic status of the mountain cat, Felis silvestris lybica, through an analysis of the cat's genome, placing the cat in an evolutionary context relative to other species and subspecies of cats. These arcane taxonomic distinctions are important for conservation because scientists have to be sure they are all talking about the same animal when discussing strategies, and no less important, because legal protections have to be specific to the group in question. Without an agreed-upon taxonomy, legal protections and conservation come to a stop.

Another important result of this study is the finding that domestic cats in China are derived from the same common stock and origin as domestic cats throughout the world, and that there was not an independent origin of domesticity in China. Previous studies have hinted at close associations between early Chinese farming communities and local wild animals, including Asian mountain cats, and that some of these animals may have begun the crossing from the wild to living with people in settled communities.

What the current study shows is that this did not happen with domestic cats; now the focus of research can move to determining - why? Why were some species domesticated in some place but not in others? Why did these processes happen when they did, and what were the conditions obtaining that allowed, maybe even promoted, the integration of wild animals into human societies? Answering these related questions will help us understand the history of early China, indeed helps us understand the history of the ancient anthropocentric world, in more detail.

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CAPTION

Chinese mountain cat.

CREDIT

Song Dazhao, CFCA

The job you want vs. the job you get

Research connects dream jobs with the future of work

UNIVERSITY OF HOUSTON

Research News

IMAGE: KEVIN HOFF, ASSISTANT PROFESSOR OF PSYCHOLOGY, UNIVERSITY OF HOUSTON REPORTS THE EXISTENCE OF IMPORTANT DISCREPANCIES BETWEEN YOUNG PEOPLE'S DREAM JOBS AND EMPLOYMENT REALITIES. view more 

CREDIT: UNIVERSITY OF HOUSTON

When it comes to career aspirations for teenagers, a University of Houston psychology researcher believes it's best to shoot for the moon, so you can at least land in the stars. The truth is the moon may sometimes be unreachable.

In the Journal of Career Assessment, Kevin Hoff, assistant professor of psychology, reports the existence of important discrepancies between young people's dream jobs and employment realities.

"Almost 50% of adolescents aspired to investigative or artistic careers, which together account for only 8% of the U.S. labor market," reports Hoff, whose research examined the career aspirations of 3,367 adolescents (age 13-18 years) from 42 U.S. states. Investigative jobs include those in the field of science and research.

Hoff's team conducted a large-scale coding effort using the Occupational Information Network (O*NET) to compile the automation risk levels, educational requirements, and vocational interests of career aspirations.

"Results revealed that most adolescents aspired to careers with low potential for automation. However, there were large discrepancies between adolescents' aspirations and the number of jobs available in the labor market," said Hoff.

For females, the most popular aspirations were doctors, veterinarians, teachers, and nurses. Doctor was most popular in early adolescence (accounting for around 12% of all female aspirations at ages 13-15), whereas veterinarian, teacher, and nurse were more popular in late adolescence (ages 16-18). For males, athlete was overwhelmingly the most popular aspiration during early adolescence (accounting for 22-32% of male aspirations at ages 13-15) but became less popular in late adolescence (accounting for 5-13% at ages 16-18).

"Both males and females showed a similar pattern of increasing variability in their career aspirations with age, indicating more diverse career goals," said Hoff. Indeed, reality may have set in. Many 13-year-old males who wanted to be professional athletes had changed their minds by 18 to aspire towards more attainable jobs.

One of the most important ways to help children find ambitious, yet realistic career goals is through exposing them to a variety of career types they would not naturally see in their daily lives.

"Young girls often want to become teachers because that is what they see every day," said Hoff. "It's equally important to show them that other occupations exist, especially lesser-known careers with growing employment demands, such as those in the STEM fields." Hoff said teachers often struggle with directing students who have very lofty career ambitions but mediocre grades, although there's an upside to having such ambition.

"Adolescents who want to become doctors may end up with a really good job doing something else in the medical field, and that's a positive outcome. The negatives are they might end up working toward an unattainable career, pursuing education that's a bad fit in interest or ability," said Hoff.

Despite a rapidly changing labor market, little research exists on how youth's career goals correspond to projections about the future of work. "This kind of career development research can make a positive impact in helping individuals and societies prepare for the future of work," said Hoff.

In the end, Hoff's work does not discourage ambition, but amplifies the need for a good back-up plan.

"It's good to encourage students to have prestigious careers, but as they get older, parents, teachers or counselors should also be real with them and help them understand how many people actually work in their dream fields, and how likely it is they will get a job in that field," said Hoff.

Spoiler alert: Only 2% of Americans are employed in the arts.

Hoff's team included Drake Van Egdom, University of Houston; Alexis Hanna, University of Nevada-Reno; Chris Napolitano and James Rounds, University of Illinois at Urbana-Champaign.

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Are zebra mussels eating or helping toxic algae?

MICHIGAN STATE UNIVERSITY

Research News

 

While invasive zebra mussels consume small plant-like organisms called phytoplankton, Michigan State University researchers discovered during a long-term study that zebra mussels can actually increase Microcystis, a type of phytoplankton known as "blue-green algae" or cyanobacteria, that forms harmful floating blooms.

"Microcystis literally means small cell, but numerous cells cluster together in colonies that can float to the surface to form scums," said Orlando Sarnelle, a professor emeritus with the Department of Fisheries and Wildlife within the College of Agriculture and Natural Resources. "It is one of the most common causes of nuisance algal blooms in nutrient-enriched waters, including Lake Erie where it is a concern for municipal water supplies."

In the 1990s, researchers observed the appearance of dime-sized zebra mussels in Gull Lake, Michigan. Shortly after the mussels arrived, the researchers noticed an increase in Microcystis, which was surprising because the lake has low levels of phosphorus and Microcystis has a well-documented need for high-nutrient waters.

"Lakes colonized by zebra mussels tend to have about three times more Microcystis," said Stephen Hamilton, a professor at the W.K. Kellogg Biological Station and the Department of Integrative Biology within the College of Natural Science, who was also curious to see if there was a relationship between the Microcystis and zebra mussels.

"We observed that zebra mussels can filter out the Microcystis with other particles, but then they spit out the Microcystis because evidently it is unpalatable to them," Hamilton said.

Sarnelle collaborated with Hamilton on a multiyear study that was part of the National Science Foundation's Long-Term Ecological Research Network. Forty years ago, the NSF recognized the need for research studies that lasted more than a few years and launched the LTER Network. This study is one of five projects highlighted in a recent issue of the Ecological Society of America's journal, Ecosphere.

"Long-term measurements are essential to our understanding of many ecological phenomena," Sarnelle said. "There are many things you can't answer in the typical two- to four-year grant cycle."

The researchers suspected the zebra mussels were consuming competitors of Microcystis, which paved the way for the cyanobacteria to flourish under lower nutrient availability than it usually needs. In 2010, an unexpected summer die-off of zebra mussels in Gull Lake during prolonged warm temperatures provided a whole-lake test of the relationship, an opportunity that scientists sometimes call a "natural experiment."

"Normally, Microcystis thrives in warmer water," said Jeffrey White, who was a graduate student advised by Sarnelle at the time and is now a faculty member at Framingham State University in Framingham, Massachusetts. "Instead, we saw an 80% decrease in the Gull Lake Microcystis population when the zebra mussels died despite optimal temperatures for its growth."

The researchers were able to use the long-term study data to confirm their hypothesis.

"This fortuitous observation following years of sampling strengthens the argument that there is a cause-and-effect relationship, and not just a correlation, between zebra mussels and increased Microcystis," Hamilton said. "Multiyear studies can catch slow, unusual or extreme events that could be making important changes resulting in long-term lasting effects in the ecosystems."

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Spreading of infections = need for collaboration between biology and physics

UNIVERSITY OF COPENHAGEN - FACULTY OF SCIENCE

Research News

 

IMAGE: THE FIGURE SHOWS A MODEL OF A SOCIAL NETWORK. THERE ARE 150 INDIVIDUALS (THE DOTS), WHOSE SOCIAL CONNECTIONS ARE MARKED BY THE LINES BETWEEN THEM. THERE ARE THREE CATEGORIES: 1.... view more 

CREDIT: BJARKE FROST NIELSEN/KIM SNEPPEN

Researchers at the Niels Bohr Institute, University of Copenhagen, together with epidemiologist Lone Simonsen from Roskilde University form part of the panel advising the Danish government on how to tackle the different infection-spreading situations we have all seen unfold over the past year. Researchers have modelled the spread of infections under a variety of scenarios, and the Coronavirus has proven to not follow the older models of disease spreading. An increasingly varied picture of its behaviour and thus its impact on society has emerged. In several scientific articles, researchers have described the knowledge accrued to date, most recently around the concept of "superspreaders". It turns out that only approximately 10% of those infected account for roughly 80% of the spread of the infection. The results have been published in the scientific journal Proceedings of the National Academy of Sciences, PNAS.

Where does our knowledge of infections spreading stem from?

The data researchers use to" feed" and develop computer models comes from a wide range of different sources. The Danish municipalities have kept inventories of the spread of the infection, and this data has the advantage that it stems from units that are not overly large. There is a high degree of detail and this means that one can trace local development more clearly and thus construct parameters for superspreading, which Postdoc Julius Kirkegaard has contributed to. Contact tracing is another source of information. In that case, the focus is on localising and limiting the individual's transmission of the virus. The third source is slightly more complicated as it seeks to follow the chain of infections via the gene sequence of the virus.

Who are the superspreaders?

Regardless of which source researchers examine, the results deliver roughly the same: 10% of all those infected account for as much as 80% of the spread of the infection. It is therefore crucial, in relation to the spread of the virus to locate the so-called superspreaders and uncover how superspreading occurs. Researchers stress that, at the moment, we are not quite sure what constitutes a person as a superspreader. It may purely be down to personal, physiological characteristics. In addition, there are varying degrees of superspreading in the population, so it is not necessarily just one or the other. Some people simply spread the virus more than others and the variation from persons with almost no transmission to superspreaders is great.

How do researchers model a population of just under 6 million individuals?

Three basic categories are considered important when modelling the population's behaviour, when calculating a scenario for the spread of infection: 1. The family context, 2. Work context and 3. The random contexts people find themselves in - in other words, people in proximity on public transport, at leisure activities etc. The time factor in all three is crucial, as it takes time to infect other people. In terms of time, these three categories are somewhat identical when it comes to common diseases, but not a superpreader coronavirus variant.

But this is where the individual characteristics of the virus come into play: Superspreaders are quite different when handled in a computer model. Methods known from physics become important here, as it is necessary to model individuals and their contacts. Researchers have set up computer models both for scenarios with and without superspreaders, and it transpires that shutting down workspaces as well as sporting events, and public transport has the same effect when the model does not take superspreaders into account. But when we include superspreaders, there is a pronounced difference, and the shutdown of public events has a much greater effect.

Disease modelling faces new challenges and strong interdisciplinary collaboration

Diseases can behave very differently and it is therefore incredibly important to be both ready and capable of rapid change in relation to the development of new models that reflect the characteristics of different diseases as accurately as possible, if we hope to contain them. Professor Kim Sneppen explains:" The biological variation of different viruses is enormous. SARS-CoV-2 contains a special feature in that it is at its most contagious just before one develops symptoms. This is the exact opposite of an earlier disease that threatened to become a pandemic, namely SARS, which is mostly contagious after one displays symptoms. Viruses are extremely advanced machines that each find specific weak points to exploit. A new field of research is rapidly developing, which examines how viruses attack the cells in our body. COVID-19 has proven to lead to very different sickness progressions for different patients. In that senses, it behaves chaotically, as we say in physics.".

Ph.D. student Bjarke Frost Nielsen and Professor Kim Sneppen see a large open field of research within the collaboration between physics and biology. Gathering as much possible information about different viruses is crucial thus enabling physists to deploy this knowledge in mapping scenarios to respond to them.

The potential for research into the spread of infections is great

Bjarke Frost Nielsen says:" We need to create a toolbox that contains a wide variation in the way we tackle the spread of transmission, in our computer programs. This is the immediate perspective we can see in front of us, at the moment. Mathematical disease modelling has been around for almost 100 years, but unfortunately not a lot of headway has been made over that period. To put it bluntly, the same equations from the 1930's are still in use today. In relation to some diseases, they can be correct, but in relation to others they can be way off. This is where, as physicists, we have a completely different approach. There are numerous parameters, i.e., social dynamics and much more varied interactions between individuals that we can build our scenarios upon. This is badly needed, when we see the enormous variations in the different diseases".

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New findings unveil a missing piece of human prehistory

CHINESE ACADEMY OF SCIENCES HEADQUARTERS

Research News

 

IMAGE: GEOGRAPHICAL AND TEMPORAL DISTRIBUTION OF NEWLY SAMPLED INDIVIDUALS view more 

CREDIT: IVPP

A joint research team led by Prof. FU Qiaomei from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences sequenced the ancient genomes of 31 individuals from southern East Asia, thus unveiling a missing piece of human prehistory.

The study was published in Cell on June 24.

Prof. FU's team used DNA capture techniques to retrieve ancient DNA from Guangxi and Fujian, two provincial-level regions in southern China. They sequenced genome-wide DNA from 31 individuals dating back 11,747 to 194 years ago. Of these, two date back to more than 10,000 years ago, making them the oldest genomes sampled from southern East Asia and Southeast Asia to date.

Previous ancient DNA studies showed that ~8,000-4,000-year-old Southeast Asian Hòabìnhian hunter-gatherers possessed deeply divergent Asian ancestry, whereas the first Southeast Asian farmers beginning ~4,000 years ago show a mixture of ancestry associated with Hòabìnhian hunter-gatherers and present-day southern Chinese populations. In coastal southern China, ~9,000-4,000-year-old individuals from Fujian province show ancestry not as deeply divergent as the Hòabìnhian.

In Guangxi, FU and her team's sampling showed that the ancestry present was unlike that sampled previously in Fujian and Southeast Asia. Instead, they found a unique East Asian ancestral population (represented by the 11,000-year-old Longlin individual from Guangxi). Their findings highlight that 11,000 years ago, at least three genetically distinct ancestries composed the human landscape in southern East Asia and Southeast Asia: Fujian ancestry, Hòabìnhian ancestry, and Guangxi ancestry.

In addition to sharing Longlin ancestry, the Dushan and Baojianshan individuals in Guangxi also show strong evidence for admixture in southern China ~9,000 to 6,000 years ago. Dushan and Baojianshan were a mixture of local Guangxi ancestry, southern ancestry previously sampled in Fujian, and Deep Asian ancestry related to Southeast Asian Hòabìnhian hunter-gatherers.

Previously, it was shown that southern Chinese populations expanded to Southeast Asia, mixing with and eventually replacing Hòabìnhians in Southeast Asia. FU's team showed that the dynamics were more complex, since populations carrying Hòabìnhian ancestry either co-existed with populations carrying Guangxi ancestry in southern China or gene flow upwards from Southeast Asia to southern China also occurred as early as ~8,000-6,000 years ago.

The study fills a research gap in the region connecting East and Southeast Asia, revealing a new genetic ancestry different from that found in coastal areas of southern China and in Southeast Asia.

Furthermore, it shows the impact of migration and admixture of populations at the crossroads of East and Southeast Asia in the last 11,000 years, revealing a long history of intermingling between these two regions.

"While we now have a better understanding of the population history in the last 11,000 years at the crossroads of East and Southeast Asia, future sampling in regions near the Yangtze River and southwest China are needed for a comprehensive understanding of the genetic history of humans in southern China," said Prof. FU.

Genetic samples from ancient humans in these regions will likely further clarify the remarkably diverse genetic prehistory of humans in southeastern Asia, and inform the genetic shifts that occurred between 6,000 and 1,500 years ago and contributed to the genetic composition observed today in southern China.

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Overview of population dynamical history at the crossroads of East and Southeast Asia since 11,000 years ago

CREDIT

IVPP

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Phylogenetic tree of early Asian populations

CREDIT

 

People with fibromyalgia are substituting CBD for opioids to manage pain

The cannabis-derived substance provides fewer side effects, with less potential for abuse

MICHIGAN MEDICINE - UNIVERSITY OF MICHIGAN

Research News

 

Fibromyalgia is one of many chronic pain conditions that remains stubbornly difficult to treat.

As the ravages of the opioid epidemic lead many to avoid these powerful painkillers, a significant number of people with fibromyalgia are finding an effective replacement in CBD-containing products, finds a new Michigan Medicine study.

CBD, short for cannabidiol, is the second most common cannabinoid in the cannabis plant, and has been marketed for everything from mood stabilization to pain relief, without the intoxicating effects produced by the most common cannabinoid, THC. THC, which stands for delta-9-tetrahydrocannabinol, is the ingredient in marijuana that causes people to feel high.

The cannabis industry has exploded, aided by the legalization of medical and recreational marijuana in states around the United States and the removal of hemp-derived CBD from Schedule 1 status--reserved for drugs with no currently accepted medical use and a high potential for abuse--at the federal level.

Previous research shows that some people substitute medical cannabis (often with high concentrations of THC) for opioids and other pain medications, reporting that cannabis provides better pain relief and fewer side effects. However, there is far less data on CBD use.

"CBD is less harmful than THC, as it is non-intoxicating and has less potential for abuse," said Kevin Boehnke, Ph.D., a research investigator in the Department of Anesthesiology and the Chronic Pain and Fatigue Research Center. "If people can find the same relief without THC's side effects, CBD may represent a useful as a harm reduction strategy."

Boehnke and his team surveyed people with fibromyalgia about their use of CBD for treatment of chronic pain.

"Fibromyalgia is not easy to treat, often involving several medications with significant side effects and modest benefits," Boehnke explained. "Further, many alternative therapies, like acupuncture and massage, are not covered by insurance."

For this study, the team focused on 878 people with fibromyalgia who said they used CBD to get more insight into how they used CBD products.

The U-M team found that more than 70% of people with fibromyalgia who used CBD substituted CBD for opioids or other pain medications. Of these participants, many reported that they either decreased use or stopped taking opioids and other pain medications as a result.

"I was not expecting that level of substitution," said Boehnke, noting that the rate is quite similar to the substitution rate reported in the medical cannabis literature. People who said they used CBD products that also contained THC had higher odds of substitution and reported greater symptom relief.

Yet the finding that products containing only CBD also provided pain relief and were substituted for pain medications is promising and merits future study, noted Boehnke.

The team noted that much of the widespread use of CBD is occurring without physician guidance and in the absence of relevant clinical trials. "Even with that lack of evidence, people are using CBD, substituting it for medication and doing so saying it's less harmful and more effective," he said.

Boehnke stressed the need for more controlled research into how CBD may provide these benefits, as well as whether these benefits may be due to the placebo effect.

Clinically, opening up lines of discussion around CBD use for chronic pain is imperative, said Boehnke, for medication safety reasons as well as for "enhancing the therapeutic alliance and improving patient care."

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Additional authors include Joel J. Gagnier, Lynne Matallana and David A. Williams.

Paper cited: "Substituting Cannabidiol for Opioids and Pain Medications Among Individuals with Fibromyalgia: A Large Online Survey," The Journal of Pain. DOI: 10.1016/j.jpain.2021.04.011

Race, ethnicity not a factor in recent weapon-carrying behaviors at US schools

The University of Minnesota Medical School study says a school's social climate plays the strongest role when weapon-carrying behaviors increase

UNIVERSITY OF MINNESOTA MEDICAL SCHOOL

Research News

 

MINNEAPOLIS/ST. PAUL (06/24/2021) -- A study led by researchers at the University of Minnesota Medical School sheds new light on boys' weapon-carrying behaviors at U.S. high schools. The results indicate that weapon-carrying is not tied to students' race or ethnicity but rather their schools' social climates.

The study was published in the journal Pediatrics and led by Patricia Jewett, PhD, a researcher in the Department of Medicine at the U of M Medical School.

"Narratives of violence in the U.S. have been distorted by racist stereotyping, portraying male individuals of color as more dangerous than white males," Jewett said. "Instead, our study suggests that school climates may be linked to an increase in weapon-carrying at schools."

The study analyzed self-reported weapon-carrying behaviors among 88,000 young males at U.S. high schools between 1993 and 2019 based on data from the Youth Risk Behavior Surveillance System. From that data, they identified four key findings:

- Since 1993, weapon-carrying in schools has declined among all males.

- Over the last 20 years, in schools perceived as safer, Non-Hispanic, white males have been more likely to bring weapons into schools than Non-Hispanic Black/African American or Hispanic males.

- Between 2017 and 2019, while comparing all schools, no significant differences in weapon-carrying behaviors existed by race or ethnicity.

- More frequent weapon-carrying is associated with experiences of unsafety or violence at school. Males who experienced violence or felt unsafe at school brought weapons at least twice as often, and such negative school experiences were more common among males of color (8-12%) than among Non-Hispanic white males (4-5%).

"Our work underscores the association of experiences of unsafety at school with weapon-carrying at school and highlights large knowledge gaps in the field of gun violence research in the U.S.," Jewett said. "This is an important foundation for much needed research to disentangle the intertwined phenomena of racism, toxic environments of violence and gun- and weapon-culture in the U.S. We are currently reaching out to other researchers who work in the field to collaborate on this urgent public health topic."

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Co-authors of the study include Iris W. Borowsky, MD, PhD, with the U of M Medical School, Eunice M. Areba, PhD, with the U of M School of Nursing; Ronald E. Gangnon, PhD, and Kristen Malecki, PhD, with the University of Wisconsin, Madison; and Judith Kafka, PhD, with the City University of New York.

About the University of Minnesota Medical School

The University of Minnesota Medical School is at the forefront of learning and discovery, transforming medical care and educating the next generation of physicians. Our graduates and faculty produce high-impact biomedical research and advance the practice of medicine. We acknowledge that the U of M Medical School, both the Twin Cities campus and Duluth campus, is located on traditional, ancestral and contemporary lands of the Dakota and the Ojibwe, and scores of other Indigenous people, and we affirm our commitment to tribal communities and their sovereignty as we seek to improve and strengthen our relations with tribal nations. For more information about the U of M Medical School, please visit med.umn.edu.