Culture

Even the mention of lavender evokes the distinct fragrance of the flower. This beautiful flower has been used to make perfumes and essential oils since time immemorial. The aesthetics of the flower have captured the imagination of hundreds, worldwide. So, what makes this flower so special? What are the "magical" compounds that gives it its unique fragrance? What is the genetic basis of these compounds? These questions have long puzzled scientists.

To find out the answers, a group of scientists from China have sequenced the genome of lavender, which is known in the scientific world as Lavandula angustifolia. The team headed by Dr. Lei Shi, Professor at the Key Laboratory of Plant Resources and Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, was specifically interested in the genetics and diversity of a class of volatile terpenoids produced by lavender.

Terpenoids play important roles in the biology of fragrant flowers including lavender. In the environment, terpenoids have been shown to attract potential insect pollinators. In real-life applications, terpenoids lend their potential benefits, including stress relief and skin conditioning, through products like essential oils. Keeping these in mind, it is essential to understand the fundamentals of terpenoid biosynthesis at the genetic level to manipulate lavender to produce better quality of these compounds.

The team began by analyzing the high-quality reference genome data of the Chinese variety of lavender 'Jingxun 2'. Through phylogenetic analysis, they identified genomic events through the evolutionary history of lavender that led to the expansion of terpenoid biosynthetic genes in this species. Their analysis also yielded important insights into changes in these genes with respect to changes in the environment under which they grew.

Firstly, the scientists assembled the genetic sequences of the Chinese lavender cultivar. Next, they identified and named, or "annotated," the genomic regions in the lavender sequence and performed phylogenetic analysis on these sequences to better understand the evolutionary history of the lavender. Then they identified the events that affected the entire lavender genome and specifically the terpenoid producing genes. Finally, they associated genes on the lavender genome sequences with different terpenoids found in the plant, to construct gene-terpenoid networks.

Their results, published in a recent issue of Horticulture Research, reported the successful assembly of the 894.5 Mb lavender genome sequence distributed across 27 chromosomes, and could possibly be the best quality lavender sequence assembly, so far. In addition, the scientists were able to show that lavender has exclusively undergone major genetic events, including two whole genome duplications, which allowed them to better adapt and thrive in colder Mediterranean weather conditions.

Explaining their observations, Dr. Shi says, "Plants have the capacity to duplicate their genomes and when this happens there is freedom for the duplicated genes to evolve to do other things. This has allowed plants to develop new machinery to make a diverse array of chemical compounds that are used to defend against attack from harmful microbes and herbivores, and to attract beneficial species such as bees to assist in pollination." In fact, this explanation by Dr. Shi is supported by the findings of the team's study. His team identified gene duplications caused by the previously mentioned genetic events, which in turn led to terpenoid diversification. Upon further analysis, they also observed gene clusters specifically corresponding to attractive and defensive terpenoids.

Dr. Shi is excited about the potential real-life applications of this work. "The introduction of lavender into China can be traced back to the 1950s by pioneers of the Institute of Botany, The Chinese Academy of Sciences. Degradation of the cultivated species is of concern; hence, improved varieties are urgently needed. With a better understanding of the lavender genome, scientists will have an easier time developing new varieties, which may produce high-quality essential oils, have strong ornamental uses, and are resistant to pathogens and climate fluctuations.", he exclaims.

Sharing Dr. Shi's enthusiasm, we can indeed hope this study paves the way for better varieties of lavender and provide a template for research in plant volatile-environmental interactions.

Psychology researchers at UC Santa Cruz have found that playing games in virtual reality creates an effect called "time compression," where time goes by faster than you think. Grayson Mullen, who was a cognitive science undergraduate at the time, worked with Psychology Professor Nicolas Davidenko to design an experiment that tested how virtual reality's effects on a game player's sense of time differ from those of conventional monitors. The results are now published in the journal Timing & Time Perception.

Mullen designed a maze game that could be played in both virtual reality and conventional formats, then the research team recruited 41 UC Santa Cruz undergraduate students to test the game. Participants played in both formats, with researchers randomizing which version of the game each student started with. Both versions were essentially the same, but the mazes in each varied slightly so that there was no repetition between formats.

Participants were asked to stop playing the game whenever they felt like five minutes had passed. Since there were no clocks available, each person had to make this estimate based on their own perception of the passage of time.

Prior studies of time perception in virtual reality have often asked participants about their experiences after the fact, but in this experiment, the research team wanted to integrate a time-keeping task into the virtual reality experience in order to capture what was happening in the moment. Researchers recorded the actual amount of time that had passed when each participant stopped playing the game, and this revealed a gap between participants' perception of time and the reality.

The study found that participants who played the virtual reality version of the game first played for an average of 72.6 seconds longer before feeling that five minutes had passed than students who started on a conventional monitor. In other words, students played for 28.5 percent more time than they realized in virtual reality, compared to conventional formats.

This time compression effect was observed only among participants who played the game in virtual reality first. The paper concluded this was because participants based their judgement of time in the second round on whatever initial time estimates they made during the first round, regardless of format. But if the time compression observed in the first round is translatable to other types of virtual reality experiences and longer time intervals, it could be a big step forward in understanding how this effect works.

While there are many informal descriptions of time compression in virtual reality from people who have experienced it first-hand, it's still an active area of research. One particularly well-known prior study applied virtual reality time compression to shorten the perceived duration of treatment for chemotherapy patients, but that experiment didn't compare virtual reality with conventional screen formats.

"This is the first time we can really isolate that it's not just that you're playing a video game, or the content of whatever you're seeing," Mullen said. "It's really the fact that it is virtual reality versus a conventional screen that contributes to this time compression effect."

Time compression could be useful in some situations--like enduring an unpleasant medical treatment or passing the time on a long flight--but in other circumstances, it could have harmful consequences.

"As virtual reality headsets get more comfortable to wear for longer periods of time, and as more immersive games are made for this format, I think it would be good to avoid having it become like a virtual casino, where you end up playing more because you don't realize how much time you're spending," Mullen said.

Research on game addiction shows that losing track of time during gameplay can negatively affect a player's sleep cycle and mood. These effects could be more pronounced in virtual reality, but Mullen says game designers can help to minimize the risk, perhaps by integrating a clock that would appear at regular intervals during gameplay.

It will also be important to discover why virtual reality seems to contribute to time compression. In the paper, Mullen describes one possibility, which relates to the fact that, in virtual reality, a player has less body awareness. Psychology Professor Nicolas Davidenko, a coauthor and advisor on the paper, explained why this might be important.

"In virtual reality, when you look down, you might see nothing where your body normally would be, or you might see a schematic of a body, but it won't feel like your body," Davidenko said. "There are theories that we may rely on our heartbeat and other bodily rhythms to help our brain track the passage of time, so if you have a less vivid sense of your body in virtual reality, you might be missing the pulses of this timekeeping mechanism."

Future experiments to test this theory could yield new insights to help designers maximize benefits and minimize harm from time compression as virtual reality technology continues to grow.

A new study with zebrafish shows that a deadly form of skin cancer -- melanoma -- alters the metabolism of healthy tissues elsewhere in the body. The research from Washington University in St. Louis suggests that these other tissues could potentially be targeted to help treat cancer.

"Tumors rely on a constant supply of nutrients to grow. Instead of competing with tumors for nutrients, other tissues can reprogram their metabolism to be complementary. In some instances, this may even allow healthy tissues to feed the tumor," said Gary Patti, the Michael and Tana Powell Professor of Chemistry in Arts & Sciences at Washington University and a professor of chemistry and medicine at the School of Medicine.

Patti is the corresponding author of the study published May 13 in Cell Metabolism.

Cancer consumes tremendous amounts of glucose, a key source of energy for cells in the body. Glucose, or blood sugar, is derived from food and transported around the body through the bloodstream after eating. Tumors actively soak up glucose as a fuel to support their rapid growth.

This trait is so well known that physicians regularly use it as a diagnostic test for cancer, where patients are administered a specific form of glucose that can be monitored with a PET scan. What is less clear is how a tumor's penchant for glucose affects other tissues.

"Glucose levels are tightly regulated," Patti said. "When glucose levels get too low, it's dangerous. We wanted to know whether a tumor with a high avidity for glucose might influence glucose levels in the blood."

Even when healthy people go a long period of time without eating, blood glucose levels are kept relatively constant. That is because glucose can be made by the liver when it cannot be obtained directly from food.

"As it turns out, the liver counters the impact of the tumor by synthesizing glucose," Patti said. "It's very similar to what occurs during a fast."

Working with zebrafish, Patti and co-authors including other researchers at the School of Medicine developed a new approach to study melanoma's impact on different tissues in the body that uses a technology called metabolomics.

The scientists fed the zebrafish special versions of nutrients tagged with isotope labels. These labels allowed the scientists to track where nutrients go and into what molecules they get broken down. They found that a molecule being spit out by the tumor was being taken up by the liver to make glucose.

By applying metabolomics to individual zebrafish, the scientists observed that melanoma tissues in the body consume about 15 times more glucose than the other tissues they measured. Despite this burden, the zebrafish were able to maintain circulating glucose levels, apparently by making glucose in the liver through a process that is ordinarily triggered when we go without eating.

But it was clear that otherwise healthy tissues were affected in many ways by the presence of melanoma.

The scientists examined tissues in the liver, intestine, fin, muscle, brain, blood, and eye of the zebrafish. They observed metabolic dysregulation across most of the tissues -- indicating that melanoma broadly impacts whole-body metabolism.

"There is clear metabolic crosstalk between melanoma and other tissues," Patti said. "The metabolic relationship between melanoma and liver is partly characterized by a gene called BCAT1 in the cancer cells. BCAT1 goes from essentially being turned off in healthy skin cells to being highly expressed in zebrafish melanoma. By looking at melanoma from human patients, we were able to confirm that the same pattern holds in people."

Much of the previous research on cancer has focused on the metabolism of the tumor itself.

"Our work shows that a lot of interesting metabolic changes are also occurring beyond the tumor," Patti said. "We have demonstrated that, at least in some cases, these metabolic changes in non-malignant tissues occur to support the tumor. This is exciting because it means that we might be able to target the metabolism of healthy tissues as a potential treatment for cancer."

A group of the world's leading experts in the transmission of airborne pathogens is calling for a tightened regulatory system to control air quality in buildings - as a way of reducing the spread of covid-19 and other illnesses.

Writing in the journal Science, the 40 scientists say: "A paradigm shift is needed on the scale that occurred when Chadwick's Sanitary Report in 1842 led the British government to encourage cities to organise clean water supplies and centralised sewage systems.

"In the 21st century we need to establish the foundations to ensure that the air in our buildings is clean with a significantly reduced pathogen count, contributing to the building occupants' health, just as we expect for the water coming out of our taps."

The scientists who have contributed to the analysis include Cath Noakes, Professor of Environmental Engineering for Buildings at the University of Leeds and a member of SAGE, the body that advises the UK Government on scientific emergencies.

Professor Noakes said: "Over the years, we have neglected the role that the air circulating inside a building plays in the way germs and viruses may spread between people. The pandemic has exposed that deficiency in our understanding and the way we seek to make buildings safer to use.

"We need to introduce new mechanisms that keep pathogen levels in the air flow in buildings and other enclosed spaces to a minimum. That approach can be achieved with technology backed-up with a requirement to meet new standards."

"Action to improve ventilation to reduce exposure to airborne pathogens will bring other benefits, including reducing exposure to other air pollutants and improved performance and wellbeing."

Recognising the risk of aerosol pathogen spread

Historically, public health regulations have concentrated on sanitation, drinking water and food safety, whereas the risk from airborne pathogens whether it is flu or covid-19 is "... addressed fairly weakly, if at all, in terms of regulations, standards, and building design and operation, pertaining to the air we breathe", say the scientists.

But research during the covid-19 pandemic has underlined the role that aerosols play in spreading disease. When a person who has a respiratory infection speaks, coughs or sneezes, tiny infective particles are emitted from their nose and mouth. Indoors, those tiny particles are carried in the air and infect other people.

The paper says: "... community outbreaks for COVID-19 infection in particular most frequently occur at larger distances through inhalation of airborne virus-laden particles in indoor spaces shared with infected individuals.

"Such airborne transmission is potentially the dominant mode of transmission of numerous respiratory infections. We also have strong evidence on disease transmission, for example in restaurants, ships, and schools, suggesting that the way we design, operate, and maintain buildings influences transmission."

That risk of people becoming cross infected inside a building can be reduced through ventilation coupled with air disinfection and air filtration systems. However, the scientists note: "... almost no engineering-based measures to limit community respiratory infection transmission had been employed in public buildings - excluding health care facilities - or transport infrastructure anywhere in the world."

Tighter controls

There are ventilation guidelines and standards which architects and builders must follow but the focus is on reducing odours and carbon dioxide levels and in maintaining thermal comfort. None provide recommendations on how to control the spread of pathogens.

The scientists are calling for World Health Organisation indoor air-quality guidelines, which cover pollutants such as carbon monoxide and other chemicals, to be extended to include airborne pathogens. The experts say individual governments need to introduce and enforce domestic regulations.

"None of this means that every indoor space should become a biosafety facility. It means that a building should be designed and operated according to its purpose and the activities conducted there, so that airborne infection risk is maintained below an acceptable level," the scientists write in the paper.

That would mean different standards for a gym where people may be breathing heavily as opposed to people relaxing in a cinema.

The lead author of the paper, Lidia Morawska, Distinguished Professor in the School of Earth and Atmospheric Sciences at Queensland University of Technology in Australia, said: "For decades, the focus of architects and building engineers was on thermal comfort, odour control, perceived air quality, initial investment cost, energy use, and other performance issues, while infection control was neglected."

Quotes from other authors of the paper

Trish Greenhalgh, Professor of Primary Care Health Sciences at the University of Oxford, said: " It's no exaggeration to call this a paradigm shift. Up to now, most of the efforts to prevent transmission of Covid-19 and other airborne respiratory diseases such as tuberculosis has focused on influencing individual behaviour such as mask-wearing, cough hygiene and handwashing. These measures are still important, but they will be relatively ineffective in the indoor environment until we ensure that the air we inhale contains far fewer particles that have been exhaled by others in the room.

"We need to re-think the practice, currently common in many countries, of keeping windows closed and recycling stale air in air-conditioning. Windows should be opened and draughty rooms welcomed; if air is recycled it must be filtered and disinfected; and monitoring air quality--for example using CO2 monitors--should become commonplace. In short, we need to re-think--and re-regulate--what counts as a 'healthy' building."

Stephanie Dancer, Professor of Microbiology at Edninburgh Napier University and Consultant Medical Microbiologist at NHS Lanarkshire, in Scotland, said: "Even just opening the windows provides more than a gesture towards reducing the risk of infection."

Costs

The scientists challenge the argument that costs of air quality control in buildings would be prohibitively expensive. They say the monthly cost of covid-19 is conservatively estimated at $1 trillion. Installing ventilation and air-quality systems designed to remove airborne pathogens would add about one percent to the construction costs of a typical building.

Improving air quality in buildings would bring benefits beyond reducing sickness levels due to respiratory infections. It is likely to reduce allergens and the number of people who experience 'sick building syndrome'.

Scientists exploring the drivers of Antarctic climate change have discovered a new and more efficient pathway for the creation of natural aerosols and clouds which contribute significantly to temperature increases.

The Antarctic Peninsula has shown some of the largest global increases in near-surface air temperature over the last 50 years, but experts have struggled to predict temperatures because little was known about how natural aerosols and clouds affect the amount of sunlight absorbed by the Earth and energy radiated back into space.

Studying data from seas around the Peninsula, experts have discovered that most new particles are formed in air masses arriving from the partially ice-covered Weddell Sea - a significant source of the sulphur gases and alkylamines responsible for 'seeding' the particles.

A new study shows that increased concentrations of sulphuric acid and alkylamines are essential for the formation of new particles around the northern Antarctic Peninsula. High concentrations of other acids and oxygenated organics coincided with high levels of sulphuric acid, but by themselves did not lead to measurable particle formation and growth.

An international team of researchers from the University of Birmingham; Institute of Marine Science, Barcelona, Spain; and King Abdulaziz University, Jeddah, Saudi Arabia studied summertime open ocean and coastal new particle formation in the region, based on data from ship and land stations, and today published its findings in Nature Geoscience.

The researchers revealed that the newly discovered pathway is more efficient than the ion-induced sulphuric acid-ammonia pathway previously observed in Antarctica and can occur rapidly under neutral conditions.

Study co-author Roy Harrison OBE, Professor of Environmental Health at the University of Birmingham, commented: "New particle formation is globally one of the major sources of aerosol particles and cloud condensation nuclei. This previously overlooked pathway to natural aerosol formation could prove a key tool in predicting the future climate of polar regions.

"The key to unlocking Antarctica's climate change lies in examining particles created in the atmosphere by the chemical reaction of gases. These particles start tiny and grow bigger, becoming cloud condensation nuclei leading to more reflective clouds which direct outgoing terrestrial radiation back to earth and warm the lower atmosphere."

New particle formation is globally one of the major sources of aerosol particles and cloud condensation nuclei. Existing research suggests that natural aerosols contribute disproportionately to global warming, whilst sulphuric acid is thought to be responsible for most aerosol seeding observed in the atmosphere.

The research team identified numerous sulphuric acid-amine cluster peaks during new particle formation events - providing evidence that alkylamines provided the basis for sulphuric acid nucleation.

"We found that sulphuric acid-amine-water nucleation is a dominant process in the Antarctic Peninsula, with the amines coming from regions of sea ice in the Antarctic Peninsula-western Weddell Sea region," added Professor Harrison. "Waters in this region with significant amounts of sea ice are rich in amines, and aerosols originating from such regions show a near five-fold enhancement in amine concentrations."

Today, the rocks of the Hanna Formation in south-central Wyoming are hundreds of miles away from the nearest ocean. But around 58 million years ago, Wyoming was oceanfront property, with large hippo-like mammals traipsing through nearshore lagoons.

In a study published in Scientific Reports, geologist Anton Wroblewski, an adjunct associate professor in the Department of Geology and Geophysics, and applied biodiversity scientist Bonnie Gulas-Wroblewski of the Texas A&M Natural Resources Institute, report the discovery of several sets of fossilized tracks, likely from the brown bear-sized Coryphodon, that represent the earliest known evidence of mammals gathering near an ocean.

"Trace fossils like footprints record interactions between organisms and their environments, providing information that body fossils alone cannot," Wroblewski says. "In this case, trace fossils show that large- bodied mammals were regularly using marine environments only eight million years after non-avian dinosaurs went extinct."

The tracks that the Drs. Wroblewski found in the Hanna Formation of Wyoming include underprints, impressions in soft sediment made when heavy animals walk on overlying sediment layers, as well as prints pressed into the surfaces of ancient tidal flats. Now preserved in sandstone, the tracks are more than half a mile (one kilometer) long and were made by two different animals, one with four toes and one with five. The five-toed tracks are consistent with Coryphodon, a semi-aquatic mammal similar to a hippopotamus. The owner of the four-toed tracks remains a mystery.

"Paleontologists have been working in this area for thirty years, but they've been looking for bones, leaf fossils, and pollen, so they didn't notice footprints or trackways," Wroblewski says. He first saw the tracks in September 2019. "When I found them, it was late afternoon and the setting sun hit them at just the right angle to make them visible on the tilted slabs of sandstone. At first, I couldn't believe what I was seeing; I had walked by this outcrop for years without noticing them. Once I saw the first few, I followed out the ridge of sandstone and realized they were part of a much larger, more extensive trackway."

Fossilized plants and pollen helped the researchers determine the age of the tracks to be around 58 million years old, during the Paleocene epoch. Before this finding, the earliest known evidence of mammals interacting with marine environments came from the Eocene epoch, around 9.4 million years later. Wroblewski says that the Hanna Formation tracks are the first Paleocene mammal tracks found in the USA and only the fourth in the world, with two sets of tracks previously found in Canada and one in Svalbard, Norway. It's also the largest accumulation of Paleocene mammal tracks in the world in both aerial extent and the absolute number of tracks, he says. With at least two species leaving the tracks, it's also the most taxonomically diverse.

Today's large mammals congregate near marine environments for a variety of reasons, including protection from predators and biting insects, foraging for unique foods, and access to salt sources, which may have been limited in the tropical forests of North America during the Paleocene. The researchers say ancient mammals may have had similar reasons for seeking out a day at the beach.

The research shows, Wroblewski says, that hypotheses of behavior and evolution based on isotopic, molecular and body fossil data can be empirically tested using trace fossils. "No other line of evidence directly records behaviors of extinct organisms preserved in their preferred habitats," he says. "There's still a lot of important information out there in the rocks, waiting for somebody to spot it when the lighting is just right!"

What The Study Did: This survey study examined differences between male and female physicians in the use of social media and reported career and professional benefits.

Authors: Shikha Jain, M.D., of the University of Illinois at Chicago, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2021.9834)

Editor's Note: The article includes conflict of interest disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.

Scientists reveal that the deterioration of modern concrete and asphalt structures is due to the presence of trace quantities of organic matter in these structures.

Cement and asphalt are vital to modern construction materials; cement is used for the construction of various buildings and structures, while asphalt is primarily used for highways and runways. They have been widely used for these purposes since the 1800s. It has been observed modern concrete structures and asphalt structures tend to deteriorate much faster than historical structures, but the reason for this phenomenon was unknown.

A team of scientists from six institutions, including Akihiro Moriyoshi, Emeritus Professor Hokkaido University, have revealed that the presence of trace quantities of organic matter in modern concrete structures and asphalt pavements drive the deterioration of these structures. Their findings, which include novel methods to assess deterioration, were published in the journal PLOS ONE.

The deterioration of modern concrete structures and asphalt pavements are a major issue. The features that lead to deterioration include cracks, disaggregation (breakdown into fine white powder) and delamination (separation into layers). These deteriorated structures are unsafe for their intended purposes; rapid deterioration reduces the expected lifespan of structures, thereby increasing the costs for maintenance or replacement.

The scientists set out to develop a new method to assess the rate of deterioration in concrete. The current method is based on the width of surface cracks in concrete and a simple chemical test; however, it only gives an incomplete picture of the level of damage. During their experiments, the scientists happened to notice that a strange odor developed when commercial cement was mixed with water. They hypothesized that organic matter was responsible for the odor, and investigated the effect it has on deterioration of concrete.

The scientists developed the one-dimensional transient moisture permeation apparatus to accurately reproduce the field environmental conditions that concrete structures and asphalt pavements are exposed to, in the laboratory, over a period of 24 hours. When combined with CT scans, this method can be used to evaluate the precise extent of the damage. They tested a variety of asphalt samples from Japan dating back to 1960; a number of concrete samples from across the world were also tested, and a 120-year-old concrete sample was used as a reference.

The scientists showed that there are a number of organic molecules, from diverse sources, present in modern concrete structures and asphalt pavements: phthalates, diesel exhaust particulates, surfactants, and windshield washer fluids. These molecules are either introduced during the manufacturing process -- the contents of phthalates, phosphate compounds, and AE water reducing agents present in commercially available cements are 0.0012%, 0.12%, and 0.25%, respectively -- or absorbed from the environment, and cause rapid deterioration of concrete structures and asphalt pavements.

Of the organic matter present in cement, phthalates have the highest effect on deterioration more than phosphates and AE water reducing agents. Organic matter in water accelerates deterioration of asphalt pavements. The scientists also showed that crack width and length is the best determinant of concrete damage, while the degree of formation of amorphization is the best determinant of deterioration. They believe that their findings can be used to develop novel formulations for long-lasting concrete structures and asphalt pavements.

Higher levels of ozone from air pollution are linked to an increased risk of developing fibroids among Black American women according to a large study published today (Friday) in Human Reproduction [1], one of the world's leading reproductive medicine journals.

Fibroids are non-cancerous growths that develop in and around the womb. They are diagnosed in 25-30% of pre-menopausal women, but the true incidence is thought to be between 70-80%. Many fibroids do not cause symptoms but when they do, they are one of the main reasons women are admitted to hospital for inpatient care. Symptoms can include heavy or painful periods, stomach and back pain, constipation, frequent need to urinate, and pain or discomfort during sex. In some cases they can affect fertility and pregnancy. Women of African-Caribbean origin are diagnosed with fibroids two to three times more often than white women, and they tend to experience earlier onset of symptoms and more severe disease.

Previous research has shown that Black people are exposed to higher levels of air pollution than white people in the USA but, until now, there has been no investigation into the association between air pollution and fibroids in Black women.

The study published today investigated concentrations of three environmental pollutants in the air in 56 US metropolitan areas between 1997 and 2011: particulate matter smaller than 2.5 microns (PM2.5), nitrogen dioxide (NO2) and ozone (O3). The 21,998 premenopausal Black women who lived in these areas and were included in the research were part of the ongoing Black Women's Health Study. They answered questionnaires every two years and were followed up until 2019.

During the 14-year follow-up period, 6238 (28.4%) of women reported having fibroids diagnosed by a doctor and confirmed by ultrasound or surgery. Average (median) concentrations of ozone were 36.9 parts per billion (ppb), with a range of 25.4 to 55 ppb.

After adjusting for factors that could affect the results, such as education, smoking, body mass index, diet and whether or not the women had been pregnant, the researchers found that the risk of self-reported fibroids increased with increasing levels of ozone in the atmosphere, but not with PM2.5 or NO2.

Ozone was linked to a 35% increased risk of fibroids among the 20% of women exposed to the highest levels of ozone (42-55 ppb) - a rate of 33.6 cases per 1000 women, compared with the 20% exposed to the lowest levels (25-33 ppb) - a rate of 31.4 cases per 1000 women [2]. The association was stronger among women aged less than 35 years and for women who had been pregnant.

First author of the study, Dr Amelia Wesselink, an Assistant Professor in the Department of Epidemiology at Boston University School of Public Health (Massachusetts, USA), said: "We were surprised to see an association for ozone but not for PM2.5 and NO2. The mechanisms that we think could explain the association between ozone and fibroids are also relevant for the other pollutants, so this was an unexpected finding. It may reflect that there is a mechanism unique to ozone that we are missing, but it might also mean that there is factor that we've not been able to measure that could affect the results. For example, we were unable to account for vitamin D exposure and vitamin D deficiency is a suspected risk factor for fibroids."

Biological mechanisms that might be involved in the link between ozone and fibroids include an immune inflammatory response; oxidative stress (an imbalance between molecules in the body, leading to cell and DNA damage); high blood pressure that could lead to fatty deposits on artery walls; and activation of the body's stress response.

Dr Wesselink said that the increased risk of fibroids among Black women was not explained by known risk factors, or by socioeconomic status, or access to or quality of health care.

"We are still trying to figure out what specific exposures explain this disparity. Possible explanations that are under investigation include stress throughout life due to systematic oppression and racism; vitamin D deficiency; and environmental factors like air pollution, which we know are inequitably distributed across populations in the United States.

"There have now been three studies suggesting a link between air pollution and fibroids, but ours is the first to show this in Black women. Because Black women are inequitably exposed to air pollution, these findings have important implications for racial disparity in fibroids."

The study has some limitations. These include the way exposure to air pollution was measured; the fact that women reported doctors' diagnoses of fibroids, which could have led to an under-estimation of the problem; and that the researchers were unable to measure factors that could affect the results, such as vitamin D exposure.

Dr Wesselink said: "Vitamin D deficiency is a key hypothesis that is under investigation to explain the racial disparity in fibroids. It is certainly possible that our findings could be explained by vitamin D. This is something that should be considered in future work on this topic."

She concluded: "Further research and additional funding is needed to understand the role of air pollution in fibroid development. For instance, a prospective, ultrasound-based study could identify fibroids, regardless of whether or not they are causing symptoms that lead to women seeking medical care. In addition, we need to consider the role of other features in the physical and built environment in the development of fibroids; factors such as environmental noise, access to green spaces and other neighbourhood exposures."

People with healthier heart structure and function appear to have better cognitive abilities, including increased capacity to solve logic problems and faster reaction times, according to research led by Queen Mary University of London and the Radcliffe Department of Medicine at University of Oxford.

Dr Zahra Raisi-Estabragh, BHF Clinical Research Training Fellow at Queen Mary University of London said: "Heart disease and dementia are important and growing public health problems, particularly in ageing populations.

"We already knew that patients with heart disease were more likely to have dementia, and vice versa, but we've now shown that these links between heart and brain health are also present in healthy people. We demonstrated for the first time, in a very large group of healthy people, that individuals with healthier heart structure and function have better cognitive performance.

"With more research, these findings may help us to establish strategies for early prevention and reduce the burden of heart and brain disease in the future."

The brain has previously been proposed as a target for damage from heart disease, and the risk factors leading to heart disease have also been associated with both vascular and Alzheimer's dementia. However, the mechanisms by which these associations occur are not well understood, and studies had not been carried out in large groups of people or those without disease.

The new study, published in the European Heart Journal Cardiovascular Imaging, examined links between heart health and cognitive function in over 32,000 UK Biobank participants. The team assessed heart health using measures of anatomy and function obtained from MRI scans. Cognitive function was assessed using tests of fluid intelligence (the capacity to solve logic-based problems) and reaction time.

The results show that, in this large group of mostly healthy individuals, those with healthier heart structure and function performed significantly better in tests of cognitive ability.

To investigate underlying mechanisms for the observed relationships, the team also considered whether the links between heart and brain health may be related to shared risk factors for vascular disease, such as diabetes, smoking, high blood pressure and obesity.

They found that although these factors were important in determining both heart and brain health, they did not provide a complete explanation for the observed associations. This suggests that alternative mechanism may be important in mediating interactions across the heart and brain.

For instance, other studies have shown that proteins which are abnormally deposited in the brain in Alzheimer's disease may also accumulate and cause disease in the heart muscle. Another possibility is that poorer brain and heart health may both be a consequence of accelerated ageing.

The researchers caution that, as this was an observational study, it is not possible to make any definitive inferences about causality and it cannot be stated that heart disease causes impaired cognition, or vice versa. It is also possible that there may be residual confounding (i.e. that brain and heart health may appear to be connected due to their common association with a third factor).

Cooperation as a successful strategy has evolved in both nature and human society, but understanding its emergence can be a difficult task. Researchers have to abstract interactions between individuals into mathematical formulas to be able to create a model that can be used for predictions and simulations.

In the field of evolutionary game theory, they often investigate strategies of players in a simple game of giving and receiving benefits. Such strategies tell players how to behave in a given interaction. The scientists' findings counter the narrative that only the strongest and most selfish flourish and survive. Instead, they show how cooperation can be a successful and stable strategy.

Researchers, spearheaded by Laura Schmid from the Chatterjee group at IST Austria, have created a new mathematical framework that combines so far incompatible descriptions of cooperation. In their simulations of many interactions between players, they show how prior experiences with and reputation of a potential partner affect the willingness of a players to cooperate with them.

Scratched Backs and Flawless Reputation

The central concept in the researchers' work is that of interactions based on direct and indirect reciprocity. "An interaction based on direct reciprocity simply means 'I'll scratch your back if you scratch mine'," Laura Schmid explains, "It can be found both among humans and several animal species."

On the other hand, indirect reciprocity is based on the reputation of an individual. "This means that if they behave well towards others, I will cooperate with them, even if I have not interacted with that individual before," Schmid continues, "So far this has conclusively only been shown among humans."

Resolving conflicts that arise when these two kinds of reciprocity lead to competing suggestions is not straightforward. Should the player cooperate with a person who behaves well towards others, even if they have treated them unfairly in the past? The strategies adopted by the players then answer this kind of question.

One of the key insights the researchers gained from their unified model of both direct and indirect reciprocity was that the evolution of strategies, the amount of cooperation, as well as which kind of reciprocity individuals prefer all depend on the environment: factors like how often players interact and whether they know the truth about their partner's reputation.

Stabilized Cooperation

This model can help researchers understand the fundamental dynamics of how cooperative strategies evolve and stabilize. "Using mathematical tools that were developed only recently, we explored which strategies of direct or indirect reciprocity give rise to a Nash equilibrium," Schmid points out. "Once the evolving population of players in our simulation adopts such strategies, none of them has an incentive to divert."

These findings shed some light on how the evolution of cooperation in early human societies could have been influenced by their social norms based on experience and reputation. A more current application would be the modeling of rating systems of online stores based on both a buyer's personal experience and the reputation of a seller.

Bridging different fields such as game theory and evolutionary modeling has been a topic for Laura Schmid for some time. Growing up in Vienna, she first studied physics at TU Wien as well as piano at the Music and Arts University of the City of Vienna before joining the Chatterjee group at IST Austria for her PhD. After completing her degree later this year, she plans to continue her research career abroad.

In her future work, Laura Schmid wants to look into how many players in a group have to use a strategy based on indirect reciprocity for it to become successful. With this, she will be able to investigate the effect of the spread of social norms within a society.

The majority of children infected with SARS-CoV-2 may not show typical symptoms such as fever, cough or shortness of breath, according to a study published in Scientific Reports, which examined data on 12,306 children with laboratory-confirmed COVID-19 across the United States.

Pakaj Arora and colleagues found that 18.8% of the children included in the study were recorded as having symptoms such as fever, malaise, muscle or joint pain, and disturbances of smell or taste. . 16.5% of children had respiratory symptoms including cough and shortness of breath, 13.9% had gastrointestinal symptoms such as nausea, vomiting and diarrhea, 8.1% had dermatological symptoms (rash), and 4.8% had headaches.

5.5% (672) of children included in the study were hospitalized. Of those, 118 (17.6%) and 38 (4.1%) required critical care services and mechanical ventilation, respectively. The risk of hospitalization was similar between males and females, but higher in non-Hispanic Black and Hispanic children compared with non-Hispanic White children. The risk of requiring critical care and mechanical ventilation was similar across all groups.

The findings suggest that children and adolescents with COVID-19 may have a milder course of illness than adults, but disparities in severity appear to exist between non-Hispanic Black, Hispanic and non-Hispanic White children in the US. Given the high frequency of cases without typical symptoms, increased vigilance, innovative screening, and frequent testing may be required among school-going children and their immediate contacts as schools reopen. Implementation of these strategies may need to be enhanced among children from racial/ethnic minorities to curtail the existing COVID-19 related health disparities.

New research led by the University of Kent has found that adolescents and older adults pay less attention to social cues in real-world interactions than young adults.

The findings published by Nature Human Behaviour show that social attention undergoes age-related change, which has potential implications for how successfully we can interpret social interactions in daily life and throughout the lifespan.

Interpreting the facial expression, tone of voice and gestures of others is a vital element of social interaction that allow us to make rapid inferences about others' mental states, such as their intentions, emotions, desires and beliefs. Successful social interaction prompts perspective-taking and empathy along with other essential social skills, and plays an important role in enhancing our wellbeing.

The research led by PhD student, Martina De Lillo, alongside Professor Heather Ferguson and other colleagues at the University of Kent's School of Psychology, is the first of its kind to examine how social attention is allocated during adolescence and whether it differs from adulthood. Furthermore, no previous research has examined the lifespan developmental differences of social attention while people actively participate in real-world interactive situations.

The researchers recorded participants in two real-world social interaction situations (a face-to-face conversation and navigating an environment) using mobile eye-tracking glasses to monitor their attention to social and non-social information. Adolescents (10-19 years old), young (20-40 years old) and older (60-80 years old) adults were assessed in both scenarios.

In the first experiment adolescents and older adults spent less time looking at the experimenter's face during conversation, and more time fixating the background, compared to young adults. In the second experiment adolescents and older adults spent less time looking at people while navigating a busy University environment, compared to young adults. This is likely because adolescents and older adults found the social situation more challenging to maintain than young adults, and they managed this difficulty by avoiding the complex social information of the face.

Martina De Lillo said: 'Using mobile eye-tracking technology allowed us to gain a unique understanding into social interaction and the everyday use of social cognition in real-world contexts. It can play a critical role in further understanding how social interaction develops across the lifespan.'

Professor Ferguson said: 'Focusing less on people and their faces means that adolescents and older adults miss important cues, and this could lead to larger impairments in social interaction, or less opportunities to engage in social interaction with others.

'During adolescence, 10-19-year-olds are still learning and developing peer relationships, so they are experiencing a rapid change in their social experiences and preferences. For older adults, a substantial decline in social participation can lead to isolation, loneliness and poor health. Both groups can therefore be significantly impacted by a lack of social engagement.'

Multiple studies have shown that African American women with breast cancer have lower survival rates than white women with the disease. But the association between race or ethnicity and treatment outcomes in triple-negative breast cancer -- an aggressive type of tumor that does not respond to hormonal or other targeted therapies -- has not been well defined.

Now, new research from Washington University School of Medicine in St. Louis shows that non-Hispanic African American women with triple-negative breast cancer also do not fare as well as non-Hispanic white women with this type of breast cancer. The study demonstrates the need for additional research to address disparities in cancer care and understand whether tumor biology or nonbiological reasons such as systemic racism -- or a combination of such factors -- may prevent African American women from receiving the same quality of care as white women.

The study appears online May 13 in JAMA Oncology.

Among women with triple-negative breast cancer, the researchers found that African Americans had a 28% increased risk of death compared with Americans of European descent, and that this disparity was at least partially due to lower rates of surgery and chemotherapy among African American patients.

"Regardless of subtypes of breast cancer, many studies have shown that African American patients have lower survival than white patients," said epidemiologist and senior author Ying Liu, MD, PhD, an assistant professor of surgery in the Division of Public Health Sciences. "But there have been conflicting studies on triple-negative breast cancer outcomes. Some of these studies have shown no disparity in survival, but these were smaller studies with fewer triple-negative or African American patients. Our research uses a large study from a national dataset demonstrating that African American patients also have lower survival for this type of breast cancer. If we want to eliminate these disparities, we must first identify what they are and work to understand what drives them."

Breast cancer is classified into categories based on whether the tumor's growth is driven by hormones such as estrogen or progesterone or by proteins such as HER2, called growth factors. Hormonal therapies that block or reduce these hormones and drugs that target HER2 can be effective in treating these tumor types. In contrast, triple-negative breast cancer continues to grow even in the absence of all these hormones and growth factors, forcing doctors and patients to rely on surgery, chemotherapy and, less often, radiation.

About 10% to 12% of all invasive breast cancer diagnoses in the U.S. are triple-negative. And for reasons that remain unclear, African American women are at higher risk of developing triple-negative breast cancer than white American women.

For the study, researchers mined a large database maintained by the National Cancer Institute that included over 23,000 women diagnosed with triple-negative breast cancer from 2010 to 2015. Twenty-five percent of the patients were African American, and patients' tumors were stages 1, 2 or 3, but not stage 4, meaning they had not yet spread to other parts of the body. In a follow-up 3½ years later, 3,276 patients had died from breast cancer. The five-year survival rate was about 77% for African American women and about 83% for white women.

Compared with white patients, African American patients had 31% lower odds of receiving surgery and 11% lower odds of receiving chemotherapy. Radiation therapy is used less often for this type of cancer, but the researchers found no difference between the two groups. After adjusting for socioeconomic factors, tumor stage and size, treatment differences and other factors, the risk of death among African Americans remained increased by 16%.

Even when chemotherapy was given, there was some evidence that the treatment was less effective in African American patients. "This suggests there may be differences in tumor biology or tumor environment between African American and white patients," said Liu, also a research member of Siteman Cancer Center. "We need more research to understand if any differences exist between these tumors in their molecular biology or in their immune landscape, for example, so we can try to address them with different targeted therapies."

On average, African American patients were diagnosed at younger ages (56 years) than white patients (59 years). Tumors of African American patients also tended to be larger, diagnosed at more advanced stages and included more lymph node involvement, which is a sign the cancer is beginning to spread.

Additionally, African American patients were more likely to have health insurance through Medicaid and to live in urban areas and in counties that were more socioeconomically disadvantaged.

"There are a lot of factors beyond tumor biology that are likely contributing to these disparities," Liu said. "Our study couldn't measure many of these factors, but we know, for example, that African American patients are more likely to have unsatisfying communications with their doctors, experience discrimination in the health-care system, and have more difficulty with transportation to and from their appointments."

Curiously, researchers said the racial disparity in mortality was not found among triple-negative breast cancer patients over age 65 or those living in rural or socioeconomically poorer counties.

"Some of these associations are difficult to explain because data is limited," Liu said. "We can speculate that perhaps health care in rural or poorer communities is more difficult for cancer patients to access in general, so perhaps disparities are less apparent. But at this point, we don't know. We will need more research to understand what factors are causing these differences in treatment and survival, so that we can find ways to address them."

University of Massachusetts Amherst neuroscientists examining genetically identified neurons in a songbird's forebrain discovered a remarkable landscape of physiology, auditory coding and network roles that mirrored those in the brains of mammals.

The research, published May 13 in Current Biology, advances insight into the fundamental operation of complex brain circuits. It suggests that ancient cell types in the pallium - the outer regions of the brain that include cortex - most likely retained features over millions of years that are the building blocks for advanced cognition in birds and mammals.

"We as neuroscientists are catching on that birds can do sophisticated things and they have sophisticated circuits to do those things," says behavioral neuroscientist Luke Remage-Healey, associate professor of psychological and brain sciences and senior author of the paper.

For the first time, the team of neuroscientists, including lead author Jeremy Spool, who worked as a National Institutes of Health (NIH) postdoctoral fellow in Remage-Healey's lab, used viral optogenetics to define the molecular identities of excitatory and inhibitory cell types in zebra finches (Taeniopygia guttata) and match them to their physiological properties.

"In the songbird community, we've had a hunch for a long time that when we record the electrical signatures of these two cell types, we say - 'that's a putative excitatory neuron, that's a putative inhibitory neuron.' Now we know that these features are grounded in molecular truth," Remage-Healey says. "Without being able to pinpoint the cell types with these viruses, we wouldn't be able to learn how the cell and network features bear resemblance to those in mammals, because the brain architectures are so different."

The research team used viruses from a collection curated by co-author Yoko Yazaki-Sugiyama at the Okinawa Institute of Science and Technology in Japan to conduct viral optogenetic experiments in the brain. With optogenetics, the team used flashes of light to manipulate one cell type independent of the other. The team targeted excitatory vs. inhibitory neurons (using CaMKIIα and GAD1 promoters, respectively) in the zebra finch auditory pallium to test predictions based on the mammalian pallium.

"There's so much work out there on the physiology of these different cell types in the mammalian cortex that we were able to line up a series of predictions about what features birds may or may not have," Spool says.

The CaMKIIα and GAD1 populations in the songbird were distinct "in exactly the proportions you would expect from the mammalian brain," Spool says. With the cell type populations isolated, the researchers then examined systematically whether each population would correspond to the physiology of their mammalian counterparts.

"As we kept moving forward, again and again these cell populations were acting as if they were essentially from the mammalian cortex in a lot of physiological ways," Spool says.

Remage-Healey adds, "The correspondence between the cortex in mammals and what we're pulling out with molecularly identified cell types in birds is pretty striking."

In both birds and mammals, these neurons are thought to support advanced cognitive functions, such as memory, individual recognition and associative learning, Spool says.

Remage-Healey says the research, supported by NIH grants, helps delineate "the basic nuts and bolts of how the brain operates." Knowing the nuts and bolts builds foundations necessary to develop breakthroughs that could lead to neurological interventions for brain disorders.

"This can help us figure out what brain diversity is out there by unpacking these circuits and the ways they can go awry," Remage-Healey says.