Culture

What The Study Did: Researchers investigated the effectiveness of using measurements of how pupils react to light as physiologic biomarker to help diagnose sports-related concussion in adolescents.

Authors: Christina L. Master, M.D., of Children's Hospital of Philadelphia, 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/jamaophthalmol.2020.3466)

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AURORA, Colo. (Sept. 24, 2020) - Some forms of blindness and visual impairment can be cured with a corneal transplant surgery using donated eye tissue. However, federal regulations in the United States and Canada severely restrict the ability of sexually active gay and bisexual men from donating their eye tissue.

Corneal donation in the United States is limited by a decades-old policy that bans men from becoming donors if they have had sex with another man in the past five years. Canada similarly bans corneal donations from men who had sex with another man during the previous 12 months.

These restrictions disqualified as many as 3,217 corneal donations from gay and bisexual men in 2018, despite a worldwide need for corneas for vision-restoring surgery and a lack of scientific evidence of harm caused by corneas from these men, according to a new study published in the September 24 issue of the journal JAMA Ophthalmology.

"With millions of people across the world in need of corneal transplants, these discarded corneas from gay and bisexual men could be used to address the shortage and safely restore vision to thousands of patients with corneal blindness or visual impairment," said lead author Michael A. Puente, MD, assistant professor of ophthalmology at the University of Colorado School of Medicine.

The study is the first of its kind to review how these policies have restricted corneal donations and prevented patients from receiving sight-restoring care.

The U.S. Food and Drug Administration's prohibition on corneal donation by men who have sex with men was instituted in May 1994, out of concern that HIV rates were disproportionately high in that demographic. At the time, HIV tests were unreliable up to six months after viral exposure. Since then, however, HIV testing has become faster and increasingly reliable, identifying infection within four to eight days of exposure. All corneal donors in the United States are required to undergo three separate HIV tests. Despite these advances, the FDA continues to require gay and bisexual corneal donors to be abstinent for five years, even if all three HIV tests are negative.

"With modern virologic testing and a better understanding of the low risk of HIV transmission through corneal transplants, this five-year deferral policy for gay men is not supported by current science," Puente said. "We ask federal regulators to reconsider these outdated policies which are depriving patients of the possibility of sight restoration."

The United States and Canada are outliers when it comes to restricting corneal donations from gay and bisexual men, the article says. Many countries, including Spain, Italy, Mexico, Chile, and Argentina, allow gay and bisexual men to donate their eye tissue just as easily as heterosexual donors. Other countries have deferral periods far shorter than five years. For example, the United Kingdom allows corneal donation by gay and bisexual men after only three months of abstinence, while the Netherlands and France only require gay and bisexual corneal donors to be abstinent for four months.

The article in JAMA Ophthalmology also reports that the risk of HIV transmission via corneal transplantation is low, further indicating that the restrictions should be reconsidered.

There has never been a reported case of HIV transmission through corneal transplant surgery. In 10 reported cases of corneal transplants from the 1980s and 1990s using tissue from donors who were found to be HIV-positive after surgery, none of the corneal recipients contracted the virus. Meanwhile, all 12 patients who received solid organ transplants, such as hearts, lungs, and kidneys, from those same donors did contract HIV, indicating that the corneas did not carry enough virus, if any, for transmission. These cases date from a time when HIV tests were unreliable, but now all corneal donors in the United States and Canada are required to undergo three separate highly reliable modern HIV tests. The cornea's avascularity likely prevents it from being a major reservoir of the virus, the JAMA Ophthalmology article says.

To calculate the number of corneal donations lost in one year due to the federal restrictions on corneal donation by gay and bisexual men, Puente and his co-authors surveyed all 65 eye banks in the United States and Canada to investigate how many potential corneal donors were disqualified in 2018 due to these federal restrictions. The survey data was gathered from May 2019 to February 2020.

Fifty-four of the 65 eye banks responded to the inquiries. Of those responding, 24 were able to provide a specific number of donation referrals that were rejected specifically due to the federal restrictions on gay and bisexual corneal donors. Using the reported data, Puente and his colleagues calculated an estimated number of potential corneal donations that were discarded in 2018 due solely to the donors' sexual orientation. They estimate it was between 1,558 and 3,217 eyes.

The need for donated corneas is substantial. An estimated 12.7 million people around the world need a corneal transplant, with only one cornea available for every 70 corneal transplants needed. Despite improvements in the reliability and efficiency of HIV tests, restrictive federal policies for cornea donations have not changed, even as limits on blood donation have been relaxed.

Prior to 2015, gay men in the United States were subject to a lifetime ban on blood donation. In 2015, an FDA review concluded that a lifetime ban was no longer scientifically justified and subsequently recommended that gay blood donors must be abstinent for one year. In April 2020, the FDA announced that blood donors should be deferred for only three months in cases when a man had sexual contact with another man. In cases of solid-organ donation, there is no deferral period at all. Meanwhile, gay corneal donors are still required to be abstinent for five years.

"If it's safe for gay men to donate their blood after three months of abstinence, I can think of no scientific reason to continue to require gay men to be abstinent for five years to donate their eyes," Puente said. "This policy can be changed without increasing the risk of HIV transmission, and I would urge authorities to act as soon as possible to help patients who are waiting for sight-restoring surgery."

During the initial phase of COVID-19 lockdown, rates of loneliness among people in the UK were high and were associated with a number of social and health factors, according to a new study published this week in the open-access journal PLOS ONE by Jenny Groarke of Queen's University Belfast, UK, and colleagues.

Loneliness is a significant public health issue and is associated with worse physical and mental health as well as increased mortality risk. Systematic review findings recommend that interventions addressing loneliness should focus on individuals who are socially isolated. However, researchers have lacked a comprehensive understanding of how vulnerability to loneliness might be different in the context of a pandemic.

In the new study, researchers used an online survey to collect data about UK adults during the initial phase of COVID-19 lockdown in the country, from March 23 to April 24, 2020. 1,964 eligible participants responded to the survey, answering questions about loneliness, sociodemographic factors, health, and their status in relation to COVID-19. Participants were aged 18 to 87 years old (average 37.11), were mostly white (92.7%), female (70.4%), not religious (57.5%) and the majority were employed (71.9%).

The overall prevalence of loneliness, defined as having a high score on the loneliness scale (ie., a score of 7 or higher out of 9), was over a quarter of respondents: 26.6%. In the week prior to completing the survey, 49% to 70% of respondents reported feeling isolated, left out or lacking companionship. Risk factors for loneliness were being in a younger age group (aOR: 4.67 - 5.31), being separated or divorced (OR: 2.29), meeting clinical criteria for depression (OR: 1.74), greater emotion regulation difficulties (OR: 1.04), and poor-quality sleep due to the COVID-19 crisis (OR: 1.30). Higher levels of social support (OR: 0.92), being married/co-habiting (OR: 0.35) and living with a greater number of adults (OR: 0.87) were protective factors.

The authors hope that these findings can inform support strategies and help to target those most vulnerable to loneliness during the pandemic.

Groarke adds: "We found that rates of loneliness during the early stages of the UK lockdown were high. Our results suggest that supports and interventions to reduce loneliness should prioritise young people, those with mental health symptoms, and people who are socially isolated. Supports aimed at improving emotion regulation, sleep quality and increasing social support could reduce the impact of physical distancing regulations on mental health outcomes."

The explosive growth of internet use leads to an explosion of the energy consumption of data centers. Vertical cavity surface emitting lasers VCSELs are key enabling devices meeting the requirements of optical interconnects in such data centers up to a few hundred meters of single or multimode fiber due to their simplicity, low cost, and large data transmission rates. Achieving larger bit rates has been the stated goal of research and development during the last years. The next challenge will be to focus on reducing the energy consumption of the lasers and drivers--a function of the bit rate. The energy cost of transmission at potentially the largest possible bit rates, use of predistortion or forward error correction needs to be compared with the energy cost of data transmission and device life time at lower bit rates. Finally, end of life considerations of the total cost of data centers will move the focus of operators of such centers.

Recently, Prof. Bimberg's group at Bimberg Chinese-German Center for Green Photonics Changchun at Institute of Optics, Fine Mechanics, and Physics, Chinese Academy of Sciences has developed VCSELs emitting at 850 nm, 880 nm, 910 nm, 940 nm, which were optimized to achieve 50+ Gb/s, enabling 200+ Gb/s data transmission across a multimode fiber. This was based on the PAM2-modulation scheme without any kind of predistortion leading to a spectral efficiency around 2 bit.

Furthermore, by optimization of the maximum bit rate of a system, the device lifetime, and the system's energy consumption, this group has demonstrated that 200 Gb/s transmission also can be achieved by using eight lasers with 25 Gb/s each. At 25 Gb/s EDR is even lower than 100 fJ/bit, presenting a 75% reduction as compared to the 50 Gb/s values. For the same BR of 200 Gb/s 50% energy reduction is achieved, although the number of devices has been doubled. In addition, the current density at operating conditions is reduced by 60% and risk of device failure is reduced.

Longer device lifetime together with the reduction total energy consumption by 50% will overcompensate the cost of doubling the number of devices. Lower power consumption leads to less heat, and temperature induced roll-over of the output power occurs at larger currents. Finally, less energy for cooling needs to be provided. Thus, the end of life cost is increased dramatically by choosing two lasers at a medium bit rate instead of one laser operating at maximum technically possible bit rate.

Tsukuba, Japan - Tiny organisms head out on the highway, looking for adventure like they've ridden straight out of the 1960s rock hit, "Born to Be Wild." Researchers from Japan have discovered that while perhaps not as thrill-seeking, bacteria do indeed travel on fungal highways and pay a toll in return.

In a study published this month in Life Science Alliance, researchers from the University of Tsukuba have revealed a mutual bacterial-fungal relationship that lets bacteria travel in exchange for thiamine.

Thiamine (vitamin B1) is essential to the health of almost all living organisms, and is synthesized by bacteria, plants, fungi and some protozoans. Free thiamine is scarce in the environment, and organisms appear to have developed numerous ways of obtaining it.

"Some species have developed mutually beneficial strategies that allow them to coexist," says lead author of the study Professor Norio Takeshita. "But few strategies that satisfy the need for nutrients and physical niches have been documented. So, we examined the interaction of a fungus and a bacterium to investigate strategies that meet those needs."

To do this, the researchers used transcriptomic analyses (i.e., examining all the RNA molecules of an organism), as well as genetic, molecular mass and imaging methods, including live imaging. Stable isotope labeling was used to investigate thiamine transfer from bacteria to the fungus.

"The bacteria cultured with the fungus traveled along fungal filaments using their flagella," explains Professor Nozomu Obana, senior author. "They dispersed farther with the expansion of the fungal colony than they would have otherwise, suggesting that the fungal filaments supply space for bacteria to migrate, disperse and multiply."

The fungus in this study is a type that can synthesize thiamine on its own, but used thiamine produced by the bacteria. Because these bacteria synthesize thiamine extracellularly, neighboring bacteria and fungi in nature could uptake it and use it, saving them the cost of synthesizing it themselves.

"We're proposing a new mutualistic growth mechanism in bacterial-fungal interactions, in which the bacteria move along the fungal highway and pay thiamine as a toll to the growing fungal filaments," says Professor Takeshita.

This research and future studies will contribute to an understanding of selective microbial communication, and live imaging could be used to screen for affinities between bacteria and fungi. Research in this area could be applied to a range of settings from fermentation, biomass degradation, and the promotion of plant growth, as well as plant and human pathogenesis.

High levels of air pollution are forcing people inside to consume more electricity, subsequently causing even greater environmental problems by increasing greenhouse gas emissions.

This is according to a new study from researchers at Cardiff University who have shown that the effects are seen more in lower-income families and those from ethnic minority backgrounds.

The team say the results should encourage decision makers to think about how policy can prevent inequality from widening in terms of both health risks and financial hardships.

The study, which has been published in the journal Nature Energy, examined the energy consumption of over 4,000 residential buildings and 17,000 commercial buildings in the city of Phoenix, Arizona between 2013 and 2018.

The Phoenix metropolitan area has the highest air pollution levels in the United States, with pollution being generated from both natural sources, such as dust storms, and human activities such as energy generation and transport.

The energy consumption data from the buildings in Phoenix was compared to levels of pollution in the area, allowing the researchers to tell whether households with distinct income levels or from various ethnic groups responded to air pollution differently.

The results showed that higher levels of pollution were associated with higher electricity consumption in residential buildings, with increases mainly happening in the daytime.

Higher pollution levels also resulted in higher electricity consumption in commercial buildings in the retail and recreation industries.

"Our results indicate that when air pollution levels are high, people tend to reduce travelling and shift to indoor activities, which lead to more electricity consumption in general, whether it be from heating, cooling and lighting or the increase use of appliances" said lead author of the study Dr Pan He from Cardiff University's School of Earth and Ocean Sciences.

"Lower-income or Hispanic consumers experienced a larger increase, possibly because they have low energy efficiency in their homes and are more exposed to air pollution."

The researchers also examined the impact of high levels of air pollution on energy supplies, specifically solar panels.

It is believed that solar panels can lose their efficiency as air pollution not only absorbs and scatters the sunlight in the air, but also gets deposited on the surface of the panels which hampers their power generation.

Indeed, the results showed that air pollution reduced the power generated by solar panels in both the residential and commercial buildings, with the latter less affected potentially because the panels are better maintained and cleaned.

"Our findings show the importance of considering the interactions and feedbacks of consumer behavior and solar energy systems to air pollution issues," Dr He continued.

"A cost-benefit analysis when accounting for the damages presented in this paper could produce larger welfare gains from pollution control policies. Meanwhile, it is critical to reduce the socio-economic vulnerability in adapting to air pollution, which can be achieved by improving the energy efficiency in the homes of specific income and ethnic groups."

CAMBRIDGE, MA - September 24, 2020--This week, the American Academy of Arts and Sciences and the MIT Press published a new issue of Daedalus that features essays by sixteen prominent climate change witnesses, representing multiple fields, backgrounds, and generations. Guest edited by Nancy L. Rosenblum (Harvard University), the volume assembles personal narratives from men and women immersed in the greatest problem of our time, perhaps of all time.

The many and varied dangers of climate change propel scientists, doctors, public health experts, social scientists, lawyers, journalists, business consultants, and military officers to speak out from the vantage point of their specialized knowledge. We call them witnessing professionals. Their personal narratives describe paths into climate-related work, the constraints imposed on them by disciplinary boundaries and by standard codes of professional ethics, and the need to move beyond them.

Witnessing professionals act on the imperative to communicate widely what they know, and reflect on the broader ethical challenges and political demands of addressing decision-makers and the public. They build institutions to extend their work. Climate change shapes their professional identity and expands their sense of responsibility. They push the bounds of their fields and they push themselves as witnessing professionals. The authors describe painful setbacks while balancing on the knife-edge of hope.

Witnessing Climate Change includes the following essays:

"Introduction: Paths to Witnessing, Ethics of Speaking Out" by Nancy L. Rosenblum (Academy Member; Harvard University)

"On Becoming Witnessing Professionals" by Robert Jay Lifton (Academy Member; Columbia University; CUNY)

"What Is the Social Responsibility of Climate Scientists?" by Naomi Oreskes (Academy Member; Harvard University)

"Witnessing for the Middle to Depolarize the Climate Change Conversation" by Robert H. Socolow (Academy Member; Princeton University)

"The Professional Ethics of Witnessing Professionals" by Dennis F. Thompson (Harvard University)

"An Environmental Lawyer's Fraught Quest for Legal Tools to Hold Back the Seas" by Michael B. Gerrard (Columbia University)

"Racism as a Motivator for Climate Justice" by Mark A. Mitchell (George Mason University)

"From Air Pollution to the Climate Crisis: Leaving the Comfort Zone" by Patrick L. Kinney (Boston University)

"Climate in the Boardroom: Struggling to Reconcile Business as Usual & the End of the World as We Know It" by Rebecca Henderson (Academy Member; Harvard University)

"Task Force Climate Change: A Patron Saint of Lost Causes, or Just Ahead of Its Time?" by David W. Titley (U.S. Navy; Penn State University)

"Seeing Is Believing: Understanding & Aiding Human Responses to Global Climate Change" by Elke U. Weber (Academy Member; Princeton University)

"Less Talk, More Walk: Why Climate Change Demands Activism in the Academy" by Jessica F. Green (University of Toronto)

"A Conversation" by Nancy L. Rosenblum (Academy Member; Harvard University) and Rafe Pomerance (Woodwell Climate Research Center)

"The Coral Is Not All Dead Yet" by Carolyn Kormann (The New Yorker)

"Slow Disaster in the Anthropocene: A Historian Witnesses Climate Change on the Korean Peninsula" by Scott Gabriel Knowles (Drexel University)

"Let Me Tell You a Story" by Antonio Oposa Jr. (Lawyer, SEA Camp)

Researchers from HSE University compared the effect of two meditation practices - loving-kindness meditation (LKM) and compassion meditation (CM). Loving-kindness meditation turned out to be more effective when it comes to increasing happiness, but, in contrast with previous studies, compassion meditation also did not result in a growth of negative emotions. The paper was published in Mindfulness journal.

Meditation has long become a routine for many people, particularly in the US and Western Europe. It is used to restore energy, decrease stress, and find inspiration. Different types of meditation have different effects. Researchers are increasingly interested in these hardly measurable but nevertheless important differences in the impact that meditation practices have on people's emotional state.

In Buddhism, there is a group of practices called the 'four immeasurable meditations'. It includes loving-kindness meditation, compassion meditation, appreciative joy meditation, and equanimity meditation. While they differ from each other and can be used separately, they are all aimed at forming positive messages to others and oneself.

Judging by their names, loving-kindness meditation and compassion meditation may seem similar, but they also have rooted theoretical differences. While LKM is about the meditator's motivation to see others be happy, CM aims to alleviate the feeling of suffering.

The researchers sought to answer the question as to whether the outcomes of the two practices differ and what emotions they cause. They recommended that volunteers practice one of the meditations: the first group practiced LKM, and the second practiced CM. Each of the participants received a 15-min audio with the meditation practice instructions. The third, control, group, solved a crossword puzzle. Before and after the experiment, the participants completed a questionnaire, where they evaluated the emotions they were experiencing. A total of 201 American students participated in the experiment; none of them had practiced meditation before.

The study showed that the participants who practiced one of the meditations noticed a significant increase in happiness, as well as love and care for other people. LKM was more effective in increasing positive emotions and happiness.

'The higher effectiveness of loving-kindness meditation may be a sign that this type of meditation is more suitable to newcomers - those who have never tried meditation before,' said Ulyana Sirotina, one of the paper's authors. 'Compassion meditation is traditionally practiced after one has already mastered LKM.'

The researchers had assumed that CM would increase negative emotions, since the meditator is focused on suffering, but this did not happen. This conclusion contradicts an earlier study, where those practicing compassion experienced more sadness than before meditation. The researchers believe that the difference in the results may be due to differences in procedures: the instructions in the two experiments were different. While participants focused on compassion toward friends and strangers in the earlier study, this time they were also prompted to show self-compassion, which helped them deal with sadness. Self-compassion is likely a key factor responsible for positive emotions during CM, an assumption that could be evaluated in future studies.

These conclusions gave the researchers a deeper understanding of how strongly various meditation instructions may impact their emotional state. Since meditation is increasingly used by medical professionals and psychologists in clinical practice, such studies serve to enrich knowledge on the use of specific meditation approaches.

The team reported on their findings and conclusions in the British Journal of Sports Medicine on 26 August 2020.

In the first step, Christian Klein, Dr. Patrick Luig, Dr. Thomas Henke, Hendrik Bloch and Professor Petra Platen searched for the match scenes of all moderate and severe football injuries in the period from 2014 to 2017 that had resulted in more than one week of absence for the injured player. For this purpose, they viewed the relevant video sequences via the media portal of the German Football League. In order to systematically analyse all match scenes, they developed an observation sheet in which they recorded, for example, on which surface, after how many minutes and where on the pitch the injury occurred, whether there had been a foul, what position the player was in and where on the body the injury was located.

Predominantly knees, thighs and ankle joints

The team conclusively identified and analysed 345 situations that had led to injuries. "The majority of all injuries affected the knee joint with 24.3 percent, the thigh with 23.5 percent and the ankle joint with 19.1 percent," lists Christian Klein, PhD student in the Department of Sports Medicine and Sport Nutrition at RUB and sports consultant at VBG. Less frequent injuries concerned the shoulder (8.4 percent) and the head (7.8 percent).

Head injuries were often caused by contact between players who, for example, tried to head a ball at the same time. Shoulder injuries often resulted from indirect contact mechanisms, for example when a player falls on his shoulder after tripping on contact with an opponent. Thigh injuries often occurred without contact between players. Fouls were rarely the cause of injuries: more than 70 percent of all contact injuries were not accompanied by foul play by the opponent. In just under 20 percent of all contact injuries, the researchers found a violation of the rules by the injured player himself.

Tackling is dangerous

"Looking at the overall injury pattern, we can describe nine typical injury patterns for moderate and severe injuries," explains co-author Thomas Henke. One of the main findings of the study is that tackling is linked to a high risk of injury for the attacking player himself. Many knee injuries occur due to the respective player tackling, not through the attack of an opponent. "Tackling could therefore be a focus for preventive measures," says Petra Platen, Head of the Department of Sports Medicine and Sport Nutrition at RUB. "Didactic teaching methods for tackling as a component of technical training should be developed and implemented already in youth football."

Preventive training for fast running

Injuries without physical contact occurred mainly when a player was running fast. Injuries to the thigh muscles in particular are caused by sprints or lunges. In these cases, overload is the main injury mechanism. These findings demonstrate a great potential for preventive measures, as the causes result from physiological conditions of the injured person himself. As a preventive measure, the experts consider running training consisting of aerobic elements, anaerobic elements at high continuous speed and sprinting elements.

The large and constantly growing video database developed for the present study should be used in education programmes for coaches, referees and other professions to deliver specific training on injuries and their possible prevention for all parties involved in professional football. The research team also proposes a consensus that takes into account the definitions of playing situations, player and opponent behaviour and biomechanical injury mechanisms, using the study's observation sheet as a basis.

Apps such as Uber are an important mobility feature in many big cities. Driving others from A to B in their own car has become a job for many people. However, many drivers complain that their income is too low. In May 2019, the US television station ABC reported how Uber drivers at Washington airport artificially inflated the price of the service by all going offline at the same time. Within a few minutes, the price of the service had risen by 13 dollars, which almost doubled the amount.

How exactly does this strategy work and when is it used? This is what Dr. Malte Schröder and Professor Marc Timme from the Chair for Network Dynamics at the Center for Advancing Electronics Dresden (cfaed) and the Institute for Theoretical Physics at TU Dresden have been investigating alongside PhD students David-Maximilian Storch and Philip Marszal. The two researchers published a study in the journal Nature Communications: The applied dynamic price mechanisms generally provide incentives to artificially reduce offers and consequently increase the price.

With the dynamic price adjustment, the providers want to bring the market into balance: If demand exceeds the availability, travel costs increase. The idea is to attract more drivers to meet the high demand. At the same time, customers will have an incentive to wait.

Nevertheless, the drivers can activate the price increase themselves: "If many drivers go offline at the same time, the algorithm 'thinks' there is a shortage of drivers," explains Schröder. "It tries to attract more drivers by increasing the price: A flexible surcharge is added to the basic price for the service, which can double or even triple its cost".

By using analytical methods from game theory, Schröder and his colleagues demonstrate when the strategy is profitable. First, the demand must be sufficiently high. Otherwise, the drivers risk not finding customers after their offline phase. Moreover, people should be willing to pay the high price instead of waiting for a taxi or taking the bus. "For the drivers, these are empirical values," Storch assumes. "They have learned over time when the planes arrive with stressed business people whose journey is paid for by their employers anyway."

Moreover, the tactics are only optimal for all drivers if each of them participates in the game. Otherwise, any one of them could run the risk of being the only one to go offline and miss potential customers. Therefore, drivers have to trust each other or make arrangements - like in Washington. "The drivers at the airport know each other and all wait in the same car park," says Marszal. "Of course, communication is much easier this way than if they are spread all over the city."

The researchers have developed a model that enables the identification of offline tactics based on price trends without knowing the exact ratio of availability to demand. They analysed price data of the service in 59 cities around the world. At over 15 locations in America, Asia and Europe, the price developments for services from airports, train stations or exhibition centres were similar to those in Washington. In these cases, Uber limited the surcharge to ten dollars. "This is the most inefficient way to prevent increases in prices," says Schröder. "The trip will cost a maximum of ten dollars more, but this does not change the general incentives or the behaviour of the drivers. In principle, research has only just begun: "The collective dynamics of these kinds of apps are difficult to understand, and many questions are still open, especially in the rapidly changing mobility sector". In any case, an approach would be to offer customers alternatives, such as good local transport, and to pay drivers sufficiently. Until then, travellers should think about having a quick coffee when the journey is too expensive. Outside rush hours, prices usually fall quickly back to their normal level.

New dedicated hubs for Deaf children are needed around the country to provide new social spaces, education and support, an expert has said.

Special schools for Deaf children have had an important role in the Deaf community, acting as places people can meet and learn BSL together. But the move to inclusive education and new technology such as cochlear implants means most children with hearing loss are now educated in mainstream schools.

Deaf education should be remodelled to replace the role previously provided by specialist schools which have closed, Dr Hannah Anglin-Jaffe argues in a study in the British Education Research Journal.

Dr Anglin-Jaffe proposes Deaf education and support could be run in the same way as existing community provision in schools and other social spaces such as libraries or community centres. These hubs could act as a new iteration of the special school for the Deaf and host Deaf clubs, specialist provision, pastoral support and social activity.

The hubs could provide expertise on visual learning methods, sign language tuition for children and their families and could also facilitate a meeting place for Deaf people of all ages. The hubs would work in partnership with mainstream schools and peripatetic Teachers of the Deaf to enable access to a broad mainstream curriculum.

Dr Anglin-Jaffe said: "There is a need for Deaf children to access Deaf culture and sign language, whilst maintaining the positive achievements of inclusive practice such as raised expectations, family and community belonging and high academic achievement.

"Statistics suggest there are now less specialist provision for Deaf children in mainstream schools. We need to find new social spaces which meets the needs of Deaf children and adults."

Many special schools have closed and those that survive are faced with the threat of closure. They also support children with complex and additional needs. Whenever a school is threatened with closure grass roots activism from the Deaf community is mobilised, showing they inspire strong feelings of loyalty from parents, pupils, staff and the Deaf community.

The key features of the new Deaf education hubs proposed by Dr Anglin-Jaffe would be the ability for Deaf children to meet with their peers and use sign language. This would safeguard the existence of culturally significant places and social spaces for the Deaf community.

Hubs could be set up in areas where there are Deaf children who could benefit from access to BSL. They could be coordinated by local authorities and social enterprises.

Dr Anglin-Jaffe said: "New hubs within communities could provide linguistic support, social space and access to a peer group. Young Deaf children would spend part of their time learning and socialising there, and the majority in mainstream schools local to their families.

"From this hub 'ripples' could expand allowing Deaf children to engage as bilingual and bicultural learners moving between different languages and developing positive identities. This will challenge the perception of a hostile, inaccessible 'hearing world'. Empowering young Deaf children to see the whole world as theirs to inhabit would be a profound but welcome change at the heart of Deaf education."

New research published in EPJ B reveals that the higher-than-expected efficiency of PLEDs can be reached through interactions between triplet excitons, and impurities embedded in their polymer layers.

Molecular dynamics simulations have shown that the mysteriously high efficiency of polymer LEDs arises from interactions between triplet excitons in their polymer chains, and unpaired electrons in their molecular impurities.

Polymer LEDs (PLEDs) are devices containing single layers of luminescent polymers, sandwiched between two metal electrodes. They produce light as the metal layers inject electrons and holes into the polymer, creating distortions which can combine to form two different types of electron-hole pair: either light-emitting 'singlets,' or a non-emitting 'triplets.' Previous theories have suggested that the ratio between these two types should be around 1:3, which would produce a light emission efficiency of 25%.

However, subsequent experiments showed that the real value can be as high as 83%. In new research published in EPJ B, physicists in China, led by Yadong Wang at Hebei North University, found that this higher-than-expected efficiency can be reached through interactions between triplet excitons, and impurities embedded in the polymer.

Owing to their scientific and commercial value, PLEDs are becoming an increasingly popular field of research. The discoveries of Wang's team could now lead to more widespread applications of the devices in the future.

Within PLED polymer layers, excitons are known to be produced through the recombination of 'polarons' - distortions in electrical charges which form and disappear as electrons move through solid materials. However, other mechanisms must also be involved to explain why their luminescence efficiencies are so much higher than previous theories predicted. One proposal suggests that their electrical and optical properties of PLEDs are strongly influenced by unpaired electrons trapped within molecular impurities.

Wang and colleagues explored this idea through molecular dynamics simulations, which allowed them to recreate collisions between a non-emitting triplet exciton in a polymer chain, and an unpaired impurity electron. Their calculations revealed that light-emitting singlet excitons are among the main products of this reaction; with their overall proportion varying with the size of the impurity, and its degree of coupling with the polymer chain. For the first time, the result offers conclusive evidence that impurities can significantly boost the efficiency of PLEDs, and offers new clues about the molecular mechanisms involved.

Lesbian, gay and bisexual (LGB) individuals report higher rates of medical, non-medical, and illegal stimulant use compared to heterosexuals, mirroring patterns seen in other substance use. The study by Columbia University Mailman School of Public Health researchers provides the most detailed picture to date on stimulant use by LGB subgroups and gender. Findings are published in the American Journal of Preventive Medicine.

The researchers analyzed data from the 2015-2017 National Survey on Drug Use and Health to examine associations between sexual identity and past-year use of medical and non-medical stimulants (i.e., Adderall, Ritalin) and illegal stimulants (i.e., cocaine, crack, methamphetamine). They found that bisexual women's illegal stimulant use in the past year was fivefold that of heterosexual women (7.8% vs. 1.5%), while gay men's use was threefold that of heterosexual men (9.2% vs. 3.2%). Non-medical use of prescription stimulants was higher among gay and bisexual men than heterosexual men (5.4% and 6.6% vs. 2.4%) and among gay/lesbian and bisexual women versus heterosexual women (3.3% and 6.8% vs. 1.6%). Past-year medical use of prescription stimulants was higher among gay men than heterosexual men (6.6% vs. 4.1%) and bisexual women than heterosexual women (7.9% vs. 4.9%). There were no differences between bisexual men and women compared to their gay/lesbian counterparts.

Potential consequences of stimulant include substance use disorder and overdose, particularly given increases in fentanyl contamination in illegally produced pills and cocaine and methamphetamine. As many as half of LGB individuals who reported nonmedical and illegal stimulant use also reported nonmedical prescription opioid use.

"This study highlights the need for future interventions to target stimulant use among LGB populations, with a particular focus on harm reduction approaches," says first author Morgan Philbin, PhD, assistant professor of sociomedical sciences. "The findings have important implications across sexual identities, and demonstrate the need to disaggregate stimulant use by subgroup and gender, particularly related to polysubstance use."

Higher drug use among LGB individuals is likely a result of minority stress--that is, the fact that exposure to stigma and discrimination based on sexual orientation results in health disparities. Structural stigma (e.g., employment or housing discrimination) drives psychological and physical health morbidities among LGB populations, and perceived stigma is associated with cocaine use. Bisexuals can also experience "double discrimination" from heterosexuals and lesbian and gay communities, which the researchers say may account for the particularly high substance use among bisexual individuals.

The paper outlines several avenues to address stimulant use, including by educating healthcare providers who focus on LGB communities to screen for and discuss substance use, including stimulants. Communities and providers can also scale-up access to medication disposal and harm reduction services.

The researchers note that their dataset started assessing sexual identity among adults in 2015, so these relationships could not be examined in earlier years or among adolescents. The options for gender included only "male" or "female" and thus did not allow researchers to differentiate between transgender and cis-gender individuals. The dataset does not assess sexual behavior, so this study only captured associations based on individuals' sexual identity.

Survey of geosynchronous orbital debris led by University of Warwick found over 75% of debris detected could not be matched to known objects in public satellite catalogues

Astronomers are calling for more regular surveys with large telescopes to help quantify the risks posed to active satellites

Many of the objects detected show optical signatures of tumbling, providing insight into the dynamical evolution of debris within the geosynchronous environment

First instalment of DebrisWatch, an ongoing collaboration between the University of Warwick and the Defence Science and Technology Laboratory (UK)

University of Warwick astronomers are warning that orbital debris posing a threat to operational satellites is not being monitored closely enough, as they publish a new survey finding that over 75% of the orbital debris they detected could not be matched to known objects in public satellite catalogues.

The astronomers are calling for more regular deep surveys of orbital debris at high altitudes to help characterise the resident objects and better determine the risks posed to the active satellites that we rely on for essential services, including communications, weather monitoring and navigation.

The research forms part of DebrisWatch, an ongoing collaboration between the University of Warwick and the Defence Science and Technology Laboratory (UK) aiming to provide a fresh take on surveys of the geosynchronous region that have been conducted in the past. The results are reported in the journal Advances in Space Research. The research was part-funded by the Science and Technology Facilities Council (STFC), part of UK Research and Innovation, and was supported by the Royal Society.

This survey was optimised to search for faint debris, objects that are too small or poorly reflective to be regularly monitored and recorded in publicly available catalogues. The US Strategic Command (USSTRATCOM) maintains the most complete public catalogue of space objects, using its global Space Surveillance Network (SSN) comprising over 30 ground-based radars and optical telescopes, alongside 6 satellites in orbit. The SSN is able to monitor high-altitude objects down to roughly 1 metre in diameter. Although certain residents of the geosynchronous region are often referred to as 'stationary', collisions can still occur with relative velocities of kilometres per second. With this in mind, even small objects could cause a lot of damage to an active satellite.

Images from the survey were analysed using a custom software pipeline designed to pick out candidate debris objects and investigate their brightness over time. The resulting 'light curves' contain a wealth of information about the objects themselves, including their shape, surface properties and attitude, but are also affected by other factors like viewing geometry and atmospheric interference. Disentangling these components remains a very difficult task, and large quantities of high-quality data will be key to developing and refining the necessary techniques.

The astronomers focused their survey on the geosynchronous region, located roughly 36,000 kilometres above the Equator, where satellites orbit with a period that matches the Earth's rotation. Far above the outermost layer of the Earth's atmosphere, there are no natural mechanisms (like atmospheric drag) to induce orbital decay, so debris generated in the vicinity of the geosynchronous region will remain there for a very long time indeed.

To help them uncover faint debris, the astronomers made use of the Isaac Newton Telescope on the Canary Island of La Palma, which has a large 2.54 m aperture, allowing it to collect photons of light over a large area. They used an optimised strategy to ensure that the sunlight reflecting off of candidate objects would fall within the same pixels of the camera, to increase their chances of being detected. Strips of sky were scanned above, along and below the geostationary belt, where most of the operational geosynchronous satellites reside.

The majority of the orbital tracks detected by the astronomers had brightnesses corresponding to roughly 1 metre or less. Sure enough, over 95% of these faint detections failed to match with a known object in the publicly available USSTRATCOM catalogue, as they are too faint to be regularly and reliably monitored by the SSN. When the researchers included all their detections - including those above and below 1m - over 75% failed to match.

Lead author James Blake, a PhD student in the University of Warwick Department of Physics, said: "The light curves extracted from our survey images show just how varied these objects can be, both in terms of their physical nature and of their attitude or behaviour within orbit. Many of the faint, uncatalogued debris appear to be tumbling, showing significant brightness variation across the observation window. These sorts of features can tell us a lot about the perturbative forces acting on residents of the geosynchronous region, but also highlight that we need to be more careful when making assumptions about the properties of these objects. We need to probe the faint debris population further and obtain more data to gain a better understanding of what's out there.

"It's important that we continue to observe the geosynchronous region with large telescopes wherever possible, to start to build up a more complete feel for the faint debris environment. With this survey, we've probed deeper than ever before, and still the population appears to be climbing as our sensitivity limit is reached. While we're dealing with small number statistics here, it's unsurprising that we see many more small, faint objects than large, bright ones."

Artificial debris orbiting the Earth can originate for a number of reasons: the satellites themselves become debris when they reach the end of their mission lifetime; rocket bodies abandoned after successfully launching their payloads can explode or 'break-up' after many years in orbit; collisions can occur between orbiting bodies, sometimes resulting in thousands of new fragments; the harsh environment of space can deteriorate satellites over time, shedding bits of insulating blanket and paint flakes.

The astronomers are now investigating ways to extract even more information from the survey data, using simultaneous observations that were taken with a second, smaller instrument. They aim to foster new collaborations to ensure this survey can act as a gateway to an enduring activity.

Co-author Professor Don Pollacco, from the University of Warwick Department of Physics, said: "This kind of data will be key in the development of algorithms to characterise objects in the geosynchronous region. Remember that we're not dealing with close-up photographs here, even the big satellites appear as non-resolved blobs of light in our images. Light curves offer a great opportunity to learn more about the way these objects behave and what they might be. The more high-quality data we take, the better chance we have of developing these tools."

WASHINGTON--Scientists have spotted a once-in-a-century climate anomaly during World War I that likely increased mortality during the war and the influenza pandemic in the years that followed.

Well-documented torrential rains and unusually cold temperatures affected the outcomes of many major battles on the Western Front during the war years of 1914 to 1918. Most notably, the poor conditions played a role in the battles of Verdun and the Somme, during which more than one million soldiers were killed or wounded.

The bad weather may also have exacerbated the Spanish flu pandemic that claimed 50 to 100 million lives between 1917 and 1919, according to the new study. Scientists have long studied the spread of the H1N1 influenza strain that caused the pandemic, but little research has focused on whether environmental conditions played a role.

In a new study in AGU's journal GeoHealth, scientists analyzed an ice core taken from a glacier in the European Alps to reconstruct climate conditions during the war years. They found an extremely unusual influx of air from the North Atlantic Ocean affected weather on the European continent from 1914 to 1919. The incessant rain and cold caused by this influx of ocean air hung over major battlefields on the Western Front but also affected the migratory patterns of mallard ducks, the main animal host for H1N1 flu virus strains.

Mallard ducks likely stayed put in western Europe in the autumns of 1917 and 1918 because of the bad weather, rather than migrating northeast to Russia as they normally do, according to the new study. This kept them close to military and civilian populations and may have allowed the birds to transfer a particularly virulent strain of H1N1 influenza to humans through bodies of water. Listen to the latest episode of AGU's podcast Third Pod from the Sun to learn more about climate and pandemics.

The findings help scientists better understand the factors that contributed to making the war and pandemic so deadly, according to Alexander More, a climate scientist and historian at the Harvard University/Climate Change Institute, associate professor of environmental health at Long Island University and lead author of the new study.

"I'm not saying that this was 'the' cause of the pandemic, but it was certainly a potentiator, an added exacerbating factor to an already explosive situation," More said.

"It's interesting to think that very heavy rainfall may have accelerated the spread of the virus," said Philip Landrigan, director of the Global Public Health Program at Boston College who was not connected to the new study. "One of the things we've learned in the COVID pandemic is that some viruses seem to stay viable for longer time periods in humid air than in dry air. So it makes sense that if the air in Europe were unusually wet and humid during the years of World War I, transmission of the virus might have been accelerated."

War and weather

The rainy, cold, muddy landscapes of the Western Front are well documented by historians. Poet Mary Borden described it as "the liquid grave of our armies" in her poem "The Song of the Mud" about 1916's Battle of the Somme.

Historical accounts of early battles in France describe how the intense rain affected British, French and German troops. Newly dug trenches and tunnels filled with rainwater; muddy fields slowed the movement of troops during the day; and cold nighttime temperatures caused thousands to endure frostbite. However, little research has been done on the environmental conditions that may have caused the torrential rains and unusual cold.

In the new study, More and his colleagues reconstructed the environmental conditions over Europe during the war using data from an ice core taken from the Alps. They then compared the environmental conditions to historical records of deaths during the war years.

They found mortality in Europe peaked three times during the war, and these peaks occurred during or soon after periods of cold temperatures and heavy rain caused by extremely unusual influxes of ocean air in the winters of 1915, 1916 and 1918.

"Atmospheric circulation changed and there was much more rain, much colder weather all over Europe for six years," More said. "In this particular case, it was a once in a 100-year anomaly."

The new ice core record corroborates historical accounts of torrential rain on battlefields of the Western Front, which caused many soldiers to die from drowning, exposure, pneumonia and other infections.

Interestingly, the results suggest the bad weather may have kept mallard ducks and other migratory birds in Europe during the war years, where they could easily transmit influenza to humans by water contaminated with their fecal droppings. Mallard ducks are the main animal reservoir of H1N1 flu viruses and as many as 60 percent of mallard ducks can be infected with H1N1 every year. Previous research has shown that migratory patterns of mallards and other birds are disrupted during bouts of unusual weather.

"Mallards have been shown to be very sensitive to climate anomalies in their migration patterns," More said. "So it is likely is that they stayed put for much of that period."

The first wave of H1N1 influenza infection in Europe occurred in the spring of 1918, most likely originating among allied troops arriving in France from Asia in the fall and winter of 1917, according to previous research. The new study found the deadliest wave of the pandemic in Europe began in the autumn of 1918, closely following a period of heavy precipitation and cold temperatures.

"These atmospheric reorganizations happen and they affect people," More said. "They affect how we move, how much water is available, what animals are around. Animals bring their own diseases with them in their movements, and their migrations are due to the environment and how it changes, or how we change it."

"I think it's a very credible, provocative study that makes us think in new ways about the interplay between infectious diseases and the environment," Landrigan said.