World's smallest, best acoustic amplifier emerges from 50-year-old hypothesis

Acousto-electric devices reveal new road to miniaturizing wireless tech

DOE/SANDIA NATIONAL LABORATORIES

Research News

 

IMAGE: SCIENTISTS MATT EICHENFIELD, LEFT, AND LISA HACKETT LED THE TEAM AT SANDIA NATIONAL LABORATORIES THAT CREATED THE WORLD'S SMALLEST AND BEST ACOUSTIC AMPLIFIER. view more 

CREDIT: BRET LATTER, SANDIA NATIONAL LABORATORIES

ALBUQUERQUE, N.M. -- Scientists at Sandia National Laboratories have built the world's smallest and best acoustic amplifier. And they did it using a concept that was all but abandoned for almost 50 years.

According to a paper published May 13 in Nature Communications, the device is more than 10 times more effective than the earlier versions. The design and future research directions hold promise for smaller wireless technology.

Modern cell phones are packed with radios to send and receive phone calls, text messages and high-speed data. The more radios in a device, the more it can do. While most radio components, including amplifiers, are electronic, they can potentially be made smaller and better as acoustic devices. This means they would use sound waves instead of electrons to process radio signals.

"Acoustic wave devices are inherently compact because the wavelengths of sound at these frequencies are so small -- smaller than the diameter of human hair," Sandia scientist Lisa Hackett said. But until now, using sound waves has been impossible for many of these components.

Sandia's acoustic, 276-megahertz amplifier, measuring a mere 0.0008 square inch (0.5 square millimeter), demonstrates the vast, largely untapped potential for making radios smaller through acoustics. To amplify 2 gigahertz frequencies, which carry much of modern cell phone traffic, the device would be even smaller, 0.00003 square inch (0.02 square millimeter), a footprint that would comfortably fit inside a grain of table salt and is more than 10 times smaller than current state-of-the-art technologies.

The team also created the first acoustic circulator, another crucial radio component that separates transmitted and received signals. Together, the petite parts represent an essentially uncharted path toward making all technologies that send and receive information with radio waves smaller and more sophisticated, said Sandia scientist Matt Eichenfield.

"We are the first to show that it's practical to make the functions that are normally being done in the electronic domain in the acoustic domain," Eichenfield said.

Resurrecting a decades-old design

Scientists tried making acoustic radio-frequency amplifiers decades ago, but the last major academic papers from these efforts were published in the 1970s.

Without modern nanofabrication technologies, their devices performed too poorly to be useful. Boosting a signal by a factor of 100 with the old devices required 0.4 inch (1 centimeter) of space and 2,000 volts of electricity. They also generated lots of heat, requiring more than 500 milliwatts of power.

The new and improved amplifier is more than 10 times as effective as the versions built in the '70s in a few ways. It can boost signal strength by a factor of 100 in 0.008 inch (0.2 millimeter) with only 36 volts of electricity and 20 milliwatts of power.

Previous researchers hit a dead end trying to enhance acoustic devices, which are not capable of amplification or circulation on their own, by using layers of semiconductor materials. For their concept to work well, the added material must be very thin and very high quality, but scientists only had techniques to make one or the other.

Decades later, Sandia developed techniques to do both in order to improve photovoltaic cells by adding a series of thin layers of semiconducting materials. The Sandia scientist leading that effort happened to share an office with Eichenfield.

"I had some pretty heavy peripheral exposure. I heard about it all the time in my office," Eichenfield said. "So fast forward probably three years later, I was reading these papers out of curiosity about this acousto-electric amplifier work and reading about what they tried to do, and I realized that this work that Sandia had done to develop these techniques for essentially taking very, very thin semiconductors and transferring them onto other materials was exactly what we would need to make these devices realize all their promise."

Sandia made its amplifier with semiconductor materials that are 83 layers of atoms thick -- 1,000 times thinner than a human hair.

Fusing an ultrathin semiconducting layer onto a dissimilar acoustic device took an intricate process of growing crystals on top of other crystals, bonding them to yet other crystals and then chemically removing 99.99% of the materials to produce a perfectly smooth contact surface. Nanofabrication methods like this are collectively called heterogeneous integration and are a research area of growing interest at Sandia's Microsystems Engineering, Science and Applications complex and throughout the semiconductor industry.

Amplifiers, circulators and filters are normally produced separately because they are dissimilar technologies, but Sandia produced them all on the same acousto-electric chip. The more technologies that can be made on the same chip, the simpler and more efficient manufacturing becomes. The team's research shows that the remaining radio signal processing components could conceivably be made as extensions of the devices already demonstrated.

Work was funded by Sandia's Laboratory Directed Research and Development program and the Center for Integrated Nanotechnologies, a user facility jointly operated by Sandia and Los Alamos national laboratories.

So how long until these petite radio parts are inside your phone? Probably not for a while, Eichenfield said. Converting mass-produced, commercial products like cell phones to all acousto-electric technology would require a massive overhaul of the manufacturing infrastructure, he said. But for small productions of specialized devices, the technology holds more immediate promise.

The Sandia team is now exploring whether they can adapt their technology to improve all-optical signal processing, too. They are also interested in finding out if the technology can help isolate and manipulate single quanta of sound, called phonons, which would potentially make it useful for controlling and making measurements in some quantum computers.

CAPTION

An acousto-electric chip, top, produced at Sandia National Laboratories includes a radio-frequency amplifier, circulator and filter. An image taken by scanning electron microscopy shows details of the amplifier.

CREDIT

Photo by Bret Latter. Microscopy image courtesy of Matt Eichenfield

Sandia National Laboratories is a multimission laboratory operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy's National Nuclear Security Administration. Sandia Labs has major research and development responsibilities in nuclear deterrence, global security, defense, energy technologies and economic competitiveness, with main facilities in Albuquerque, New Mexico, and Livermore, California.

Study evaluates the filtration efficacy of 227 commercially available face masks in Brazil

Models for professional use were the most effective at retaining aerosol particles of a size equivalent to the novel coronavirus, followed by TNT masks sold in drugstores; the efficacy of fabric masks ranged from 15% to 70%

FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO

Research News

 

IMAGE: DIGITAL MICROSCOPE IMAGE OF DIFFERENT FACE MASKS MADE OF HYBRID MATERIAL. view more 

CREDIT: FERNANDO G. MORAIS

By Karina Toledo  |  Agência FAPESP - The novel coronavirus is transmitted mainly via inhalation of saliva droplets or respiratory secretions suspended in air, so that face covering and social distancing are the most effective ways to prevent COVID-19 until enough vaccines are available for all. In Brazil, fabric masks are among the most widely used because they are cheap, reusable and available in several colors or designs. However, this type of face covering's capacity to filter aerosol particles of a size equivalent to the novel coronavirus can vary between 15% and 70%, according to a study conducted in Brazil by the University of São Paulo (USP).

The study was supported by FAPESP, and the principal investigator was Paulo Artaxo, a professor in the university's Physics Institute (IF-USP). It was part of an initiative called (respire! to assure access to safe masks for the university community. The results are reported in an article in the journal Aerosol Science and Technology.

"We appraised the filtration efficacy of 227 models sold by drugstores and other common types of store in Brazil to see how much genuine protection they afford the general public," Artaxo told Agência FAPESP.

The scientists conducted a test using a device that contained a sodium chloride solution and emitted aerosol particles of 100 nanometers. SARS-CoV-2 is about 120 nanometers in diameter. A burst of aerosols was triggered, and particle concentration was measured before and after the mask.

As expected, surgical masks were most effective in the test, as were the FFP2 or N95 models certified for professional use, filtering 90%-98% of the particles. Next came masks made of non-woven fabric (TNT) or polypropylene and sold in many kinds of store, with an efficiency of 80%-90%, followed by those made of ordinary cotton, spandex or microfiber, which filtered 40% on average (15%-70%). 

Several factors were critical in enhancing or reducing the degree of protection. "Generally speaking, masks with a central seam protect less because the sewing machine makes holes that increase the passage of air. A tightly fitting top edge improves filtration significantly. Some masks made of fabric include fibers of nickel, copper or other metals that inactivate the virus and hence protect the wearer more effectively. There are even electrically charged models that retain more particles. In all cases, however, efficacy drops when the mask is washed because of wear and tear," said Fernando Morais, first author of the article. Morais is a PhD candidate at IF-USP and a researcher at the Nuclear and Energy Research Institute (IPEN), an agency of the São Paulo State Government. 

Breathability

According to Artaxo, dual-layer cotton masks filtered considerably better than single-layer models, but efficacy was hardly altered by a third layer, which reduced breathability.

"The study innovated in several ways. One was its evaluation of breathability or resistance to air passage," Artaxo said. "TNT and cotton masks were best in this regard. The FFP2 and N95 models were not as comfortable, but paper masks were the worst. This is important because if a person can't bear wearing a mask even for five minutes, it's useless."

The authors of the article note that although mask efficacy varies, all types help reduce transmission of the virus, and mask-wearing in conjunction with social distancing is fundamental to control the pandemic. They advocate mass production of FFP2/N95 masks for distribution free of charge to the general public. This "should be considered in future pandemics", according to Vanderley John, penultimate author and coordinator of (respire!, which is organized by USP's Innovation Agency.

"Transmission of the virus is demonstrably airborne and wearing a mask all the time is one of the best prevention strategies, as well as leaving doors and windows open to ventilate rooms as much as possible," Artaxo said.

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About São Paulo Research Foundation (FAPESP)

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at http://www.fapesp.br/en and visit FAPESP news agency at http://www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.

 BEWARE THE FUNGI FROM YUGGOTH

Using the fungal electrical activity for computing

A UOC scientific publication analyses and proposes techniques for correctly interpreting the fungal electrical internal activity

UNIVERSITAT OBERTA DE CATALUNYA (UOC)

Research News

 

Materials have a variety of properties that can be used to solve computational problems, according to studies in substrate-based computing. BZ computers, slime mould computers, plant computers, and collision-based liquid marbles computers are just a few examples of prototypes produced for future and emergent computing devices. Modelling the computational processes that exist in such systems, however, is a difficult task in general, and determining which part of the embodied system is doing the computation is still somewhat ill-defined.

Claiming that fungi are the most intelligent living organisms in the world sounds like an exaggeration. However, a recent study by Mohammad Mahdi Dehshibi, a UOC researcher who is contributing to a growing body of knowledge on the use of fungal materials, concurs with this idea. Its implications are numerous and practical in both the medium and the long term. They include the possibility of using fungal tissues as actual computing devices. How could we use a fungus as if it were a computer?

Converting the fungal electrical signals into messages

Fungal mycelium like Pleurotus djamor, also known as the pink oyster mushroom, can resolve an incredible range of computational geometry problems, explained Mohammad Mahdi Dehshibi in a previously published article on fungal materials. "By changing the environmental conditions, we can reprogramme a geometry and a theoretical structure of the graphics of mycelium networks and then use the electrical activity of the fungi to create computing circuits", confirmed the researcher.

In a recent study, Electrical activity of fungi: Spikes detection and complexity analysis, published by Mohammad Mahdi Dehshibi of the Scene Understanding and Artificial Intelligence Lab (SUNAI) group at the UOC Faculty of Computer Science, Multimedia and Telecommunications, in collaboration with Andrew Adamatzky of the Unconventional Computing Laboratory at the UWE Bristol, the researchers demonstrate that the pink oyster mushroom generates a series of spikes in electrical potential that are propagated by a growing mycelium.

The electrical activity property of the fungus corresponds to the extremely complex internal communication it uses, and this can be analysed and utilized to operate and develop computing measures. In the research project, the authors propose a variety of measures to be able to "translate" these electrical signals into messages according to the classification of the spikes in potential that can be detected.

The electrical signals in the fungal tissue are so faint and complex that it is impossible to analyse them using the standard techniques of neuroscience, the discipline that traditionally measures them. The researchers' proposal consists of a method for detecting spike arrival time through an exhaustive algorithm that enables fairly efficient characterization of the electrical activity.

The key to the complex language of fungi

Fungi are among the largest, most widely distributed and oldest groups of living organisms in the world. The many advantages for which they are considered an interesting material include their tremendous availability at no cost, their resilience, their capacity for self-maintenance and their rapid growth. To all of this, as demonstrated in the study, we must add the communicative complexity shown by the electrical signals of the fungus.

To obtain a better idea, the researchers have proven that the complexity of this "language" is greater than that of many human languages in terms of communication. That reality opens up the possibility of using the signals as an efficient and practical means of information transmission and computing, giving fungi a very interesting potential as computers.

"At the moment, there are two major challenges to be confronted [in being able to use fungi as computers]", explained Dehshibi. "The first is to implement a computing purpose that makes sense. The second is to characterize the properties of the fungal substrates to discover their true computational potential". These two steps are essential for building functional computing units.

Designing environmental sensors

Will we really see, then, a laptop computer with a microprocessor made with fungi? For the author, the objective of fungal computers is not to replace silicon chips, as the actions in this type of computer are too slow for that. But the properties of fungi could be used as an "environmental sensor on a large scale". Fungal networks could monitor large quantities of data flows as part of their day-to-day activity. If we were able to connect to their networks and interpret the signals, they use to process information, we could learn more about what is happening in an ecosystem and act accordingly.

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This research project is in line with Sustainable Development Goal (SDG) 9, to build resilient infrastructure, promote sustainable industrialization and foster innovation.

Related paper

Mohammad Mahdi Dehshibi, Andrew Adamatzky. "Electrical activity of fungi: Spikes detection and complexity analysis". Biosystems (2021). https://doi.org/10.1016/j.biosystems.2021.104373

UOC R&I

The UOC's research and innovation (R&I) is helping overcome pressing challenges faced by global societies in the 21st century, by studying interactions between technology and human & social sciences with a specific focus on the network society, e-learning and e-health. Over 500 researchers and 51 research groups work among the University's seven faculties and two research centres: the Internet Interdisciplinary Institute (IN3) and the eHealth Center (eHC).

The United Nations' 2030 Agenda for Sustainable Development and open knowledge serve as strategic pillars for the UOC's teaching, research and innovation. More information: research.uoc.edu. #UOC25years

ECT HAS BEEN USED FOR TORTURE

Pandemic shows essential role of ECT as treatment for severe depression

Survey of 20 centers nationwide reveals impacts of reduced services

MICHIGAN MEDICINE - UNIVERSITY OF MICHIGAN

Research News

  

IMAGE: AN ECT TREATMENT ROOM AT MICHIGAN MEDICINE, THE UNIVERSITY OF MICHIGAN'S ACADEMIC MEDICAL CENTER view more 

CREDIT: UNIVERSITY OF MICHIGAN

When the COVID-19 pandemic arrived in North America in March 2020, health care facilities stopped providing all but "essential" care, to reduce infection risks and preserve protective gear known as PPE.

That included changes at many centers that provide ECT (electroconvulsive therapy) for severe depression and other conditions, a new survey shows.

Because ECT involves anesthesia, so that patients are unconscious when carefully controlled pulses of electricity are delivered to key areas of the brain, it is considered an 'aerosol generating' procedure. That means it poses special risks when a respiratory virus such as the novel coronavirus is in widespread circulation.

In a new commentary in the American Journal of Psychiatry, a team led by Daniel Maixner, M.D., of the University of Michigan Department of Psychiatry and U-M Eisenberg Family Depression Center, describes the experiences of ECT centers during spring of 2020. Maixner leads the ECT program at Michigan Medicine, U-M's academic medical center.

Some centers temporarily stopped accepting new patients for ECT, or prioritized ECT care for only the most severely ill and hospitalized patients. Many changed the schedule for the repeated treatments that a course of ECT entails. All followed newly developed protocols to reduce staff exposure to aerosols using patient screening, used advanced personal protective equipment, also called PPE, and collaborated extensively with anesthesia teams to safely administer treatments.

In all, 16 of the centers reduced their capacity to less than half of their usual patient volume between March and June, including 5 that treated less than a quarter of their usual number of patients. For new patients, and those who had completed their initial course of treatment but needed maintenance, 18 of the 20 centers reduced the frequency of treatments.

The changes came with a price. One center lost a patient to suicide. Three other centers had patients who made serious suicide attempts. Seventy percent of sites had patients return to inpatient psychiatric care after living in the community because they weren't able to receive ECT on the planned schedule, and 80% of the centers had patients who had to restart ECT care from the beginning to get back on track.

Because of this, the authors call for ECT to be seen as "essential" in future waves of COVID-19 activity, and in other crises and pandemics, so that care can continue.

With improved availability of COVID testing and PPE, and treatment protocols, most of the academic ECT programs were able to react promptly and return to caring for most patients again by mid-summer 2020, despite many challenges.

However, Maixner said, "risks are high for our patients during the time of COVID-19 and any other pandemic if access to ECT is curtailed. It is important for psychiatrists and patients to advocate for ECT to remain an essential treatment and not just be considered elective."

The survey was conducted by the ECT Task Group of the National Network of Depression Centers. In addition to the new commentary, Maixner presented additional data on the effects of the pandemic on ECT practice at a recent meeting of the International Society for ECT and Neurostimulation, which has also issued a position statement on the essential role of ECT.

Maixner and colleagues have also studied the efficacy and cost-effectiveness of ECT as a key option for patients who have not responded to other forms of treatment for depression and other mental health conditions.

After 15 years, deep brain stimulation still effective in people with Parkinson's

AMERICAN ACADEMY OF NEUROLOGY

Research News

 

MINNEAPOLIS - Deep brain stimulation continues to be effective in people with Parkinson's disease 15 years after the device is implanted, according to a study published in the June 2, 2021, online issue of Neurology®, the medical journal of the American Academy of Neurology.

Researchers found that compared to before deep brain stimulation, study participants continued to experience significant improvement in motor symptoms, which are symptoms that affect movement, as well as a reduction in medications 15 years later.

Parkinson's disease can progressively affect speech, walking and balance due to a gradual reduction of a chemical in the brain called dopamine. Parkinson's symptoms of muscle stiffness, tremor and slowness of movement can be treated with a medication call levodopa that temporarily restores dopamine. However, that process of rising and falling levels of dopamine throughout the day can cause dyskinesia, a side effect of medication that may include twisting, swaying or head bobbing.

Deep brain stimulation controls motor symptoms from Parkinson's disease with electrodes that are placed in certain areas of the brain. The electrodes are connected to a device placed under the skin in the upper chest. The device controls the electrical impulses.

"Deep brain stimulation benefits seem to last for several years but not enough data have been available to show that these effects are still present more than 15 years after surgery," said study author Elena Moro, MD, PhD, of the Grenoble Alpes University in France and a Fellow of the American Academy of Neurology. "We wanted to know if people with Parkinson's disease continue to benefit from this treatment. It is exciting to report that our study found in the long run, deep brain stimulation continues to be effective in people with Parkinson's disease."

For the study, researchers identified 51 people who had a deep brain stimulation device implanted at the university hospital. The average age for diagnosis of Parkinson's disease was 40. The average age for device implantation was 51. Study participants had the device an average of 17 years.

Researchers reviewed data for each participant on movement problems, quality of life, medication and scores on tests that measure the severity and progression of Parkinson's disease.

Researchers found that when comparing data on participants before having a device implanted to data 15 years later, the amount of time participants experienced dyskinesia was reduced by 75%.

Researchers also found the amount of time spent in an "off state," when medication was no longer working well, was reduced by 59%. Also, the use of medications to control dopamine levels was reduced by 51%.

Researchers found few side effects of having the stimulation for 15 years and such side effects were mostly manageable.

"Our study also found that despite the natural progression of Parkinson's disease and the worsening of some symptoms that become resistant to medications over the years, participants still maintained an overall improvement in quality of life," said Moro. "Future studies should continue to examine the benefits of deep brain stimulation over longer periods of time and in larger groups of people."

A limitation of the study was that many of the people who had deep brain stimulation at the hospital were not available for study 15 years later, either because researchers were no longer able to contact them or because they had died. It is possible that the people in the study may have been healthier than those not included, meaning the results may not fully reflect the experience of all people using deep brain stimulation.

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Learn more about Parkinson's disease at BrainandLife.org, home of the American Academy of Neurology's free patient and caregiver magazine focused on the intersection of neurologic disease and brain health. Follow Brain & Life® on Facebook, Twitter and Instagram.

Learn more about Parkinson's disease at BrainandLife.org, home of the American Academy of Neurology's free patient and caregiver magazine focused on the intersection of neurologic disease and brain health. Follow Brain & Life® on Facebook, Twitter and Instagram.

When posting to social media channels about this research, we encourage you to use the hashtags #Neurology and #AANscience.

The American Academy of Neurology is the world's largest association of neurologists and neuroscience professionals, with over 36,000 members. The AAN is dedicated to promoting the highest quality patient-centered neurologic care. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer's disease, stroke, migraine, multiple sclerosis, concussion, Parkinson's disease and epilepsy.

For more information about the American Academy of Neurology, visit AAN.com or find us on Facebook, Twitter, Instagram, LinkedIn and YouTube.

 

Gender differences exist even among university students' wage expectations

Though both male and female students have optimistic wage expectations compared to actual wages of similar graduates, when given information about actual wages, women tended to decrease their expectations--while men actually increased their expectations

PLOS

Research News

 

Gender wage gaps are a well-documented issue, and expectations related to this phenomenon seem to be present even among university students discussing future employment, according to a study published June 2, 2021 in the open-access journal PLOS ONE by Ana Fernandes from the Berner Fachhochschule and the University of Fribourg and Martin Huber from the University of Fribourg, and Giannina Vaccaro from the University of Lausanne, Switzerland.

The gender wage gap is a well-established phenomenon in today's labor market, with elements both explainable (e.g. certain job paths being predominantly held by one gender) and as-yet unexplained. In this paper, the authors assessed the effect of gender on wage expectations in university students.

To gather their data, the authors surveyed a total of 865 students across two Swiss universities. The survey covered general demographic information; professional information, e.g. the type of job and workplace the student hoped to have after graduation and their expected wage (both directly after graduation and three years on); and personal information, e.g. hopes for a future family and/or children, preferences between full- and part-time work in the presence of children, home location, etc. One version of the survey included a bar graph with information on monthly gross income in the private sector.

There was a gender wage gap even among expected wages for surveyed students: this gap was 9.7 percent directly following graduation, and 11.6 percent for wages three years afterward. When comparing expected wages from the students surveyed to averages of actual wages from comparable graduates, the authors found that both men and women were optimistic about their expected wages: on average, male students' expected wages exceeded the actual wages of similar graduates by 13 percent, whereas female students' expected wages exceeded the actual wages of similar graduates by 11.2 percent. Interestingly, for those students given the extra bar graph of gross income information, male students actually increased their average expected wages (incorrectly, based on the actual wages of similar graduates), while female students tended to decrease their average expected wages.

The authors note that including the personal and professional responses in their statistical analysis greatly reduced (by approximately 30 percent) the direct, unexplained effect of gender on wage expectations. Nevertheless, a non-negligible, statistically significant direct, unexplained effect of gender on wage expectations remains for most cases under several statistical models considered.

The authors add: "Males typically forecast higher future earnings than females. We find that a broad set of personal and professional controls -- collected in an own survey of two Swiss institutions of higher education - largely accounts for those gender differences in expectations across most empirical specifications."

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Research article

Peer reviewed; Survey; People

Citation: Fernandes A, Huber M, Vaccaro G (2021) Gender differences in wage expectations. PLoS ONE 16(6): e0250892. https://doi.org/10.1371/journal.pone.0250892

Funding: G.V. Project Grant: P400PS_180732 Swiss National Science Foundation http://www.snf.ch/en/Pages/default.aspx The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: The authors have declared that no competing interests exist.

In your coverage please use this URL to provide access to the freely available article in PLOS ONE: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0250892

Transgender teens may turn to substance use to cope with stress

PLOS

Research News

 

Over half of transgender or gender minority (GM) adolescents engage in substance use, seemingly as a coping strategy in response to GM stressors, according to a new study published this week in the open-access journal PLOS ONE by Sabra L. Katz-Wise of Boston Children's Hospital and Harvard Medical School, US, and colleagues.

Compared to cisgender adolescents, adolescents who have a different gender identity than was their sex assigned at birth report higher rates of emotional distress. Previous studies have found higher prevalence of substance use among GM youth but have not examined longitudinal compounding risk factors and protective factors.

In the new study, researchers surveyed 30 GM adolescents aged 13 to 17 as part of the longitudinal Trans Teen and Family Narratives Project. Participants were asked to complete an online survey every six months for two years. GM-related stressors, including rejection, harassment and threats due to gender identity, were quantified along with substance use and possible risk and protective factors. Most participants were white (73 percent) and participants identified as trans feminine (11), trans masculine (15) and nonbinary (4).

Among all participants at the outset of the study, 17 percent reported any substance use, including tobacco, alcohol and marijuana; by the conclusion of the study two years later, 56 percent of participants reported any substance use. Higher exposure to GM stressors significantly increased the odds of alcohol use (OR=1.59, 95% CI 1.02-2.49) but not tobacco or marijuana use. Internalized transphobia was found to be a significant mediator of the association between these stressors and substance use. Increased resilience and gender-related pride tended to predict lower odds of substance use (all adjusted odds ratios below 1), and family functioning and social support both significantly moderated the association between GM stressors and alcohol use. The authors conclude that future interventions with GM youth should focus on addressing internalized transphobia and strengthening resilience, gender-related pride and family functioning.

The authors add: "This study found that gender minority adolescents use substances to cope with gender minority stress experiences. Interventions to address substance use in gender minority adolescents should focus on addressing internalized transphobia and strengthening resilience, gender-related pride, and family functioning."

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Research article

Peer reviewed; Survey; People

Citation: Katz-Wise SL, Sarda V, Austin SB, Harris SK (2021) Longitudinal effects of gender minority stressors on substance use and related risk and protective factors among gender minority adolescents. PLoS ONE 16(6): e0250500. https://doi.org/10.1371/journal.pone.0250500

Funding: The Trans Teen and Family Narratives Project was funded by grants from the Eunice Kennedy Shriver National Institute of Child Health & Human Development (K99R00HD082340) and the Boston Children's Hospital Aerosmith Endowment Fund for Prevention and Treatment of AIDS and HIV Infections, both awarded to SKW. SKW and SBA were also funded by the Maternal and Child Health Bureau, Health Resources and Services Administration (Leadership Education in Adolescent Health project 6T71-MC00009). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: The authors have declared that no competing interests exist.

In your coverage please use this URL to provide access to the freely available article in PLOS ONE: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0250500

US conservatives less able than liberals to distinguish truth from falsehoods in study of responses to 20 political news stories

Conservatives' susceptibility to political misperceptions

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE

Research News

In a six-month study of more than 1,000 Americans, R. Kelly Garrett and Robert Bond found that U.S. conservatives were less able to distinguish truth from falsehoods in 20 viral political news stories that appeared online between January and July 2019. Differences in the political orientation of these stories may help explain this observation, the researchers note, writing that "we find that high-profile true political claims tend to promote issues and candidates favored by liberals, while falsehoods tend to be better for conservatives." Two-thirds (65%) of the high-profile true stories were characterized as benefiting the political left, compared with only 10% that were described as benefiting the political right. Among high-profile false stories, 45.8% were perceived to benefit the political right while 23.3% benefited the left. While there has been a widespread perception that U.S. conservatives are likely to believe in false political news, most research in this area has focused on a narrow set of "hot-button" issues such as climate change and weapons of mass destruction in Iraq. Garrett and Bond sought to assess this idea systematically by measuring responses to a richer dataset of political information. They used a social media monitoring service to identify 10 true and 10 false viral political stories and asked the people in their study about their beliefs about those stories in 12 waves over the course of six months. The researchers then assigned 5 Democrats and 5 Republicans recruited through Amazon's Mechanical Turk service to evaluate the political slant of these belief statements. The study found that conservatives' propensity to hold misperceptions is partially explained by the political implications of widely shared news; socially-engaging, truthful claims tended to favor the left, while engaging falsehoods disproportionately favored the right. "In such an environment, the belief accuracy of liberals and conservatives would be expected to diverge even if ideological bias is symmetrical," the authors say. "Collectively, these results underscore the importance of policies designed to ensure that news shared in the political information environment is reliable and factually accurate," Garrett and Bond conclude. They note several limitations of their study, including - as with studies before theirs - the inability to provide definitive evidence as to whether bias is ideologically asymmetrical.

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Conservatives more susceptible to believing falsehoods

Study finds news environment hurts ability to find truth

OHIO STATE UNIVERSITY

Research News

 

COLUMBUS, Ohio - Conservatives are less able to distinguish political truths from falsehoods than liberals, mainly because of a glut of right-leaning misinformation, a new national study conducted over six months shows.

Researchers found that liberals and conservatives in the United States both tended to believe claims that promoted their political views, but that this more often led conservatives to accept falsehoods while rejecting truths.

One of the main drivers of the findings appeared to be the American media and information environment.

"Both liberals and conservatives tend to make errors that are influenced by what is good for their side," said Kelly Garrett, co-author of the study and professor of communication at The Ohio State University.

"But the deck is stacked against conservatives because there is so much more misinformation that supports conservative positions. As a result, conservatives are more often led astray."

Garrett conducted the study with Robert Bond, associate professor of communication at Ohio State. Their results were published today (June 2, 2021) in the journal Science Advances.

The study involved 1,204 American adults who participated online between January and June 2019.

Every two weeks, the researchers identified viral political news stories, 10 true and 10 false, that received high social media engagement.

The researchers then asked participants to assess a series of 20 statements that were based on these stories. Participants labeled each one as true or false and indicated how confident they were in their label.

In the end, participants had evaluated as many as 240 statements on a broad range of topics and representing many different viewpoints.

A separate group of people, recruited online, were surveyed to determine whether the claims, if true, would be better for liberals or for conservatives, or if they were neutral.

Overall, both liberals and conservatives were more likely to believe stories that favored their side - whether they were true or not.

The differences in beliefs were often stark, Garrett said.

For example, participants rated this true statement that received widespread social media engagement when it came out: "Investigators for the DHS Office of the Inspector General have identified poor conditions in several Texas migrant facilities, including extreme overcrowding and serious health risks."

Results showed that 54% of Democrats correctly said that the statement was "definitely true" - compared to only 18% of Republicans.

Another statement - a false one - was "While serving as Sec. of State, Hillary Clinton colluded with Russia, selling 20% of the U.S. uranium supply to that country in exchange for donations to the Clinton Foundation."

Here, only 2% of Democrats said this was "definitely true," but 41% of Republicans did.

"These are important factual claims, yet we see vast partisan differences in belief," Garrett said.

One of the major issues identified in the study was that these widely shared truths and falsehoods have different implications for liberals and conservatives.

Two-thirds (65%) of the high-engagement true statements were characterized as benefiting liberals, while only 10% of accurate claims were considered beneficial to conservatives. On the other side, 46% of falsehoods were rated as advantageous to conservatives, compared to 23% of false claims benefiting liberals.

"We saw that viral political falsehoods tended to benefit conservatives, while truths tended to favor liberals. That makes it a lot harder for conservatives to avoid misperceptions," Garrett said.

Although the information environment was the primary reason conservatives were susceptible to misinformation, it may not be the only one.

Results showed that even when the information environment was taken into account, conservatives were slightly more likely to hold misperceptions than were liberals.

"It is difficult to say why that is," Garrett said. "We can't explain the finding with our data alone."

Results did show further distinctions between how conservatives and liberals approached the political claims in the viral stories they evaluated.

Liberals showed greater overall sensitivity, which characterizes an individual's ability to distinguish truths and falsehoods. Conservatives and liberals were equally good at detecting truths and falsehoods when most true stories were labeled politically neutral.

But if more of the factually accurate stories were labeled political - benefiting either liberal or conservative positions - liberals became better than conservatives at distinguishing true from false statements.

"Conservatives did not get any worse, but they did not keep up with liberals who were getting better at discerning truths and falsehoods," Garrett said.

Conservatives also showed a stronger "truth bias," meaning that they were more likely to say that all the claims they were asked about were true.

"That's a problem because some of the claims were outlandish - there should have been no ambiguity about whether they were true or not," he said.

Garrett said a strength of this study, compared to many previous ones, is that it analyzed a wide range of political claims, reflecting the diversity of the media environment that Americans are exposed to. It clearly confirms the point made by many media commentators that conservatives are awash in false statements that support what they want to believe.

"We show that the media environment is shaping people's ability to do this very basic, fundamental task. Democracy depends on people being able to tell the difference between what is true and false and it falters when people have difficulty agreeing on what's real," he said.

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Contact: Kelly Garrett, Garrett.258@osu.edu

Written by Jeff Grabmeier, 614-292-8457; Grabmeier.1@osu.edu

WATER IS LIFE

World's lakes losing oxygen rapidly as planet warms

Changes threaten biodiversity and drinking water quality

RENSSELAER POLYTECHNIC INSTITUTE

Research News

 

IMAGE: OXYGEN LEVELS IN THE WORLD'S TEMPERATE FRESHWATER LAKES ARE DECLINING FASTER THAN IN THE OCEANS. view more 

CREDIT: GRETCHEN HANSEN, UNIVERSITY OF MINNESOTA

TROY, N.Y. -- Oxygen levels in the world's temperate freshwater lakes are declining rapidly -- faster than in the oceans -- a trend driven largely by climate change that threatens freshwater biodiversity and drinking water quality.

Research published today in Nature found that oxygen levels in surveyed lakes across the temperate zone have declined 5.5% at the surface and 18.6% in deep waters since 1980. Meanwhile, in a large subset of mostly nutrient-polluted lakes, surface oxygen levels increased as water temperatures crossed a threshold favoring cyanobacteria, which can create toxins when they flourish in the form of harmful algal blooms.

"All complex life depends on oxygen. It's the support system for aquatic food webs. And when you start losing oxygen, you have the potential to lose species," said Kevin Rose , author and professor at Rensselaer Polytechnic Institute. "Lakes are losing oxygen 2.75-9.3 times faster than the oceans, a decline that will have impacts throughout the ecosystem."

Researchers analyzed a combined total of over 45,000 dissolved oxygen and temperature profiles collected since 1941 from nearly 400 lakes around the globe. Most long-term records were collected in the temperate zone, which spans 23 to 66 degrees north and south latitude. In addition to biodiversity, the concentration of dissolved oxygen in aquatic ecosystems influences greenhouse gas emissions, nutrient biogeochemistry, and ultimately, human health.

Although lakes make up only about 3% of Earth's land surface, they contain a disproportionate concentration of the planet's biodiversity. Lead author Stephen F. Jane, who completed his Ph.D. with Rose, said the changes are concerning both for their potential impact on freshwater ecosystems and for what they suggest about environmental change in general.

"Lakes are indicators or 'sentinels' of environmental change and potential threats to the environment because they respond to signals from the surrounding landscape and atmosphere. We found that these disproportionally more biodiverse systems are changing rapidly, indicating the extent to which ongoing atmospheric changes have already impacted ecosystems," Jane said.

Watch a video about this research.

Although widespread losses in dissolved oxygen across the studied lakes are linked to climate change, the path between warming climate and changing freshwater oxygen levels is driven by different mechanisms between surface and deep waters.

Deoxygenation of surface waters was mostly driven by the most direct path: physics. As surface water temperatures increased by .38 degrees Centigrade per decade, surface water dissolved oxygen concentrations declined by .11 milligrams per liter per decade.

"Oxygen saturation, or the amount of oxygen that water can hold, goes down as temperatures go up. That's a known physical relationship and it explains most of the trend in surface oxygen that we see," said Rose.

However, some lakes experienced simultaneously increasing dissolved oxygen concentrations and warming temperatures. These lakes tended to be more polluted with nutrient-rich runoff from agricultural and developed watersheds and have high chlorophyll concentrations. Although the study did not include phytoplankton taxonomic measurements, warm temperatures and elevated nutrient content favor cyanobacteria blooms, whose photosynthesis is known to cause dissolved oxygen supersaturation in surface waters.

"The fact that we're seeing increasing dissolved oxygen in those types of lakes is potentially an indicator of widespread increases in algal blooms, some of which produce toxins and are harmful. Absent taxonomic data, however, we can't say that definitively, but nothing else we're aware of can explain this pattern," Rose said.

The loss of oxygen in deeper waters, where water temperatures have remained largely stable, follows a more complex path most likely tied to increasing surface water temperatures and a longer warm period each year. Warming surface waters combined with stable deep-water temperatures means that the difference in density between these layers, known as "stratification," is increasing. The stronger this stratification, the less likely mixing is to occur between layers. The result is that oxygen in deep waters is less likely to get replenished during the warm stratified season, as oxygenation usually comes from processes that occur near the water surface.

"The increase in stratification makes the mixing or renewal of oxygen from the atmosphere to deep waters more difficult and less frequent, and deep-water dissolved oxygen drops as a result," said Rose. Water clarity losses were also associated with deep-water dissolved oxygen losses in some lakes. However, there was no overarching decline in clarity across lakes.

Oxygen concentrations regulate many other characteristics of water quality. When oxygen levels decline, bacteria that thrive in environments without oxygen, such as those that produce the powerful greenhouse gas methane, begin to proliferate. This suggests the potential that lakes are releasing increased amounts of methane to the atmosphere as a result of oxygen loss. Additionally, sediments release more phosphorous under low oxygen conditions, adding nutrients to already stressed waters.

"Ongoing research has shown that oxygen levels are declining rapidly in the world's oceans. This study now proves that the problem is even more severe in fresh waters, threatening our drinking water supplies and the delicate balance that enables complex freshwater ecosystems to thrive," said Curt Breneman, dean of the School of Science. "We hope this finding brings greater urgency to efforts to address the progressively detrimental effects of climate change."

"Widespread deoxygenation of temperate lakes" was published with support from the National Science Foundation. Rose and Jane were joined by dozens of collaborators in GLEON, the Global Lake Ecological Observatory Network, and based in universities, environmental consulting firms, and government agencies around the world.

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About Rensselaer Polytechnic Institute

Founded in 1824, Rensselaer Polytechnic Institute is America's first technological research university. Rensselaer encompasses five schools, 32 research centers, more than 145 academic programs, and a dynamic community made up of more than 7,900 students and over 100,000 living alumni. Rensselaer faculty and alumni include more than 145 National Academy members, six members of the National Inventors Hall of Fame, six National Medal of Technology winners, five National Medal of Science winners, and a Nobel Prize winner in Physics. With nearly 200 years of experience advancing scientific and technological knowledge, Rensselaer remains focused on addressing global challenges with a spirit of ingenuity and collaboration. To learn more, please visit http://www.rpi.edu.