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Ann Arbor, June 24, 2019 - According to a new study in the American Journal of Preventive Medicine, published by Elsevier, United States Veterans seeking treatment for posttraumatic stress disorder (PTSD) are at increased risk of death compared with the general population. Veterans with PTSD are twice as likely to die from suicide, accidental injury, and viral hepatitis than the general population. Veterans with PTSD are also more likely to die from diabetes and chronic liver disease than the general population.

"Our findings suggest that treatment-seeking Veterans with PTSD, including young Veterans and women, are dying from largely preventable causes compared with the general population. PTSD is therefore a major public health concern and a priority for preventive health care," explained lead investigator Jenna A. Forehand, MD, MPH, Veterans Affairs Medical Center, White River Junction, VT, US.

This is the first study to investigate specific causes of death by age group among all-era, treatment-seeking Veterans with PTSD and compare death rates to the US general population. Veterans with PTSD had a significant increase in all-cause mortality in the year following initiation of treatment; 1.1 percent of them died, which is a 5 percent higher incidence than in the general population. Veterans with PTSD had a twofold increase in death from suicide, accidental injury, and viral hepatitis compared with the US population. Death from diabetes and chronic liver disease was also significantly higher for Veterans with PTSD. During the first year of VA PTSD treatment, younger Veterans with PTSD were more likely to die from suicide and accidental injury, whereas middle-aged and older Veterans were more likely to die from heart disease and malignant neoplasms. Among individuals dying from accidental injury, more than half died of poisoning, which could include some misclassified suicides.

This retrospective cohort study identified the leading causes of death among 491,040 Veterans who initiated PTSD treatment at any Department of Veterans Affairs Medical Center from 2008 to 2013; 5,215 of them died within the first year of care. The mean age was 48.5 years, 90.7 percent were male, 63.5 percent were of white race, and 34.9 percent served in the wars in Iraq and Afghanistan.

Causes of death during the first year of treatment were grouped according to age (18-34, 35-64, and 65 or older). To statistically compare the observed mortality among Veterans in PTSD treatment with the general population, standardized mortality ratios were calculated from age- and sex-matched mortality tables of the 2014 US population.

Because of advances in medicine and technology, Veterans who served in recent conflicts are more likely to survive combat injuries than previous generations. As a result, the prevalence of PTSD, pain disorders, and opioid use has increased among survivors. As Veterans with PTSD and comorbid pain may be at increased risk of opioid use disorder, the investigators posit that opioids may play a role in accidental injury, suicide, and hepatitis-related deaths, especially in young Veterans with PTSD. Understanding the complex nature of PTSD and its associated mortality risks is important for developing targeted interventions in this age group.

"Future studies should develop preventive interventions that target PTSD and comorbid depression, pain disorder, and substance use to lessen the risk of suicide, accidental poisoning, and viral hepatitis in Veterans with PTSD. Similarly, lifestyle modifications may reduce the risk of diabetes and chronic liver disease in this patient population. Veterans seeking treatment for PTSD should receive comprehensive education on the benefits of diet and exercise and the risks of chronic stress and substance use," commented Dr. Forehand.

Survivors of childhood brain tumors who received radiotherapy and were very young at the time of diagnosis may experience cognitive and socioeconomic burdens decades after treatment, according to a study published early online in CANCER, a peer-reviewed journal of the American Cancer Society. Interventions such as cognitive therapies and educational and occupational services may be needed to mitigate such long-term effects.

Therapies for children diagnosed with brain tumors have prolonged the lives of many patients, but survivors may experience a variety of effects from their disease and its treatment. To assess such burdens, M. Douglas Ris, PhD, of Baylor College of Medicine and Texas Children's Hospital, and his colleagues at St. Jude Children's Research Hospital, compared 181 survivors of pediatric low-grade glioma with 105 siblings of cancer survivors who were participating in the Childhood Cancer Survivor Study. The survivors and siblings all completed a comprehensive battery of standardized cognitive tests and socioeconomic assessments performed at 16 major medical centers in the United States and Canada.

Survivors were a median age of 8 years at the time of diagnosis and they were a median age of 40 years at the time of assessment. Overall, survivors treated with surgery plus radiotherapy at the site of the tumor had lower estimated IQ scores than survivors treated with surgery only, who had lower scores than siblings. Survivors diagnosed at younger ages had low scores on most of the cognitive measures. Survivors--especially those treated with surgery plus radiotherapy--were less educated, earned lower incomes, and had lower prestige occupations than siblings.

"Late effects in adulthood are evident even for children with the least malignant types of brain tumors who were treated with the least toxic therapies available at the time. Also, these neurocognitive and socioeconomic risks are evident many decades after treatment," said Dr. Ris. "As pediatric brain tumors become more survivable with continued advances in treatments, we need to improve surveillance of these populations so that survivors continue to receive the best interventions during their transition to adulthood and well beyond."

ROCHESTER, Minn. -- Micronutrient deficiencies, including vitamins B12 and D, as well as folate, iron, zinc and copper, are common in adults at the time of diagnosis with celiac disease. These deficiencies should be addressed at that time, according to a study by Mayo Clinic researchers.

The retrospective study of 309 adults newly diagnosed with celiac disease at Mayo Clinic from 2000 to 2014 also found that low body weight and weight loss, which are commonly associated with celiac disease, were less common. Weight loss was seen in only 25.2% of patients, and the average body mass index was categorized as overweight. The study will appear in the July issue of Mayo Clinic Proceedings.

"It was somewhat surprising to see the frequency of micronutrient deficiencies in this group of newly diagnosed patients, given that they were presenting fewer symptoms of malabsorption," says Adam Bledsoe, M.D., a gastroenterology fellow at Mayo Clinic's Rochester campus.

Celiac disease is an immune reaction to consuming gluten, a protein found in wheat, barley and rye. Eating gluten triggers an immune response in the small intestine that over time damages the intestine's lining and prevents it from absorbing some nutrients, leading to diarrhea, fatigue, anemia, weight loss and other complications.

Based on recent data, the prevalence of celiac disease in the U.S. is 1 in 141 people, and its prevalence has increased over the past 50 years.

"Our study suggests that the presentation of celiac disease has changed from the classic weight loss, anemia and diarrhea, with increasing numbers of patients diagnosed with nonclassical symptoms," says Dr. Bledsoe, the study's primary author. "Micronutrient deficiencies remain common in adults, however, and should be assessed." Assessment should include vitamin D, iron, folic acid, vitamin B12, zinc and copper.

Zinc deficiency was observed most frequently at diagnosis, the study says, with 59.4% of patients having a deficiency. Other deficiencies included iron, vitamin D, copper, vitamin B12 and folate.

The nutritional deficiencies have potential health ramifications, though in this retrospective study the clinical implications remain unknown. "Further studies are needed to better define the implications of the deficiencies, optimal replacement strategies and follow-up," says Dr. Bledsoe.

Scientists from the University of Nottingham have discovered that drinking a cup of coffee can stimulate 'brown fat', the body's own fat-fighting defenses, which could be the key to tackling obesity and diabetes.

The pioneering study, published today in the journal Scientific Reports, is one of the first to be carried out in humans to find components which could have a direct effect on 'brown fat' functions, an important part of the human body which plays a key role in how quickly we can burn calories as energy.

Brown adipose tissue (BAT), also known as brown fat, is one of two types of fat found in humans and other mammals. Initially only attributed to babies and hibernating mammals, it was discovered in recent years that adults can have brown fat too. Its main function is to generate body heat by burning calories (opposed to white fat, which is a result of storing excess calories).

People with a lower body mass index (BMI) therefore have a higher amount of brown fat.

Professor Michael Symonds, from the School of Medicine at the University of Nottingham who co-directed the study said: "Brown fat works in a different way to other fat in your body and produces heat by burning sugar and fat, often in response to cold. Increasing its activity improves blood sugar control as well as improving blood lipid levels and the extra calories burnt help with weight loss. However, until now, no one has found an acceptable way to stimulate its activity in humans.

"This is the first study in humans to show that something like a cup of coffee can have a direct effect on our brown fat functions. The potential implications of our results are pretty big, as obesity is a major health concern for society and we also have a growing diabetes epidemic and brown fat could potentially be part of the solution in tackling them."

The team started with a series of stem cell studies to see if caffeine would stimulate brown fat. Once they had found the right dose, they then moved on to humans to see if the results were similar.

The team used a thermal imaging technique, which they'd previously pioneered, to trace the body's brown fat reserves. The non-invasive technique helps the team to locate brown fat and assess its capacity to produce heat.

"From our previous work, we knew that brown fat is mainly located in the neck region, so we were able to image someone straight after they had a drink to see if the brown fat got hotter," said Professor Symonds.

"The results were positive and we now need to ascertain that caffeine as one of the ingredients in the coffee is acting as the stimulus or if there's another component helping with the activation of brown fat. We are currently looking at caffeine supplements to test whether the effect is similar.

Once we have confirmed which component is responsible for this, it could potentially be used as part of a weight management regime or as part of glucose regulation programme to help prevent diabetes."

ANAHEIM, CA - A first-in-human Phase 1/Phase II study demonstrates that intravenous administration of the radiopharmaceutical imaging agent technetium-99m (99mTc) tilmanocept promises to be a safe, well-tolerated, noninvasive means of monitoring rheumatoid arthritis disease activity. At present, there is no reliable noninvasive way to directly monitor inflammation in joints of RA patients. The study was presented at the 2019 Annual Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI).

According to the Rheumatoid Arthritis Support Network, rheumatoid arthritis (RA)--a chronic, autoimmune, inflammatory joint disease--affects more than 1.3 million Americans. Activated macrophages release pro-inflammatory cytokines and chemokines that significantly contribute to the initiation and propagation of RA. 99mTc tilmanocept (TCT) binds to the macrophage mannose receptor CD206, which is highly expressed on activated macrophages in RA. Previous clinical studies have shown subcutaneous administration of TCT to be safe and effective.

"Intravenous (IV) administration of TCT provides a novel noninvasive molecular imaging marker that demonstrates joint-specific, CD206-expressing synovial macrophage involvement," explains Arash Kardan, associate professor of radiology at Case Western University in Cleveland, Ohio. "It reveals potentially significant qualitative and quantitative immunodiagnostic information regarding the distribution and severity of active disease involvement in RA patients."

For the study, 39 subjects (33 with active RA and six healthy controls) were divided into 11 groups and received various combinations of intravenous 99mTc at 1, 5 and 10 mCi with 50, 200, or 400 μg of tilmanocept. They then had standard gamma camera whole-body planar imaging, as well as spot view of the hands and wrists from front to back at one hour and three hours post-injection. Twelve of the 39 subjects (six RA/six healthy controls) underwent whole-body planar scans for radiodosimetry assessment and pharmacokinetic analysis.

No adverse drug reactions or serious adverse events were observed in any dose group. Planar imaging revealed that TCT localizes specifically in the inflamed joints of RA patients and not in the joints of healthy individuals. Qualitative and quantitative data analysis and modeling established an optimal mass dose of 134 μg tilmanocept/10 mCi of 99m TC, stable over an imaging time frame of one to three hours post-injection.

For the purposes of accuracy and streamlining practice, a mass dose of 150 μg and imaging time frame of one to three hours post-injection are recommended for future use.

Kardan says, "These results enable the initiation of further clinical studies to assess if intravenous 99mTc tilmanocept imaging can provide physicians with a noninvasive, receptor-specific molecular imaging marker of rheumatoid arthritis disease activity status to guide the most effective therapeutic strategy for their patients. This includes when to initiate therapy and evaluation of response to therapy, thereby improving outcomes for all patients with rheumatoid arthritis."

ANAHEIM, CA (Embargoed until 4:30 p.m. PDT, Saturday, June 22, 2019) - Researchers have discovered a novel radioligand that can effectively differentiate progressive supranuclear palsy (PSP) from similar brain disorders, allowing for earlier and more reliable diagnosis of the disease. Presented at the Society of Nuclear Medicine and Molecular Imaging's 2019 Annual Meeting, these findings bring physicians a step closer to being able to definitively diagnose PSP with imaging rather than waiting for confirmation upon autopsy.

PSP is a rare brain disorder characterized by loss of balance, blurred vision and uncontrolled eye movement, slurred speech, cognitive decline and mood changes. The disease worsens over time, and there is no cure. Often, PSP symptoms are similar to Parkinson's disease and dementia, making it hard to diagnose.

"Currently, PSP can only be definitively diagnosed post-mortem by examining region-specific tau deposits in the brain," said Matthias Brendel, MD, MHBA, at Ludwig-Maximilians-University of Munich in Germany. "Future interventional trials targeting tau in PSP would strongly benefit from biomarkers to validate the specific presence of the tau deposits and to monitor treatment response during therapy."

In the study, researchers utilized a novel second-generation radioligand, 18F-PI-2620, to evaluate patients with suspected tau pathology in clinically diagnosed PSP. Seventeen patients with probable or possible PSP underwent 18F-PI-2620 positron emission tomography (PET) imaging at four different health care centers, along with 10 healthy control patients and seven disease control patients who had multi-system atrophy, Parkinson's disease or Alzheimer's disease. Standardized uptake value (SUV) ratios of 18F-PI-2620 in predetermined brain areas were obtained and compared between the PSP, healthy control and disease control patients. In addition, disease severity, measured by the PSP rating scale, was correlated with PET findings.

A significantly elevated mean 18F-PI-2620 SUV ratio was found in the globus pallidus and the substantia nigra areas of the brain in the PSP patients as compared to the healthy control group. In contrast, the disease control group showed similar or only slightly elevated SUV ratios when compared to the healthy control group. Furthermore, results showed that even patients with low disease severity already had significantly elevated 18F-PI-2620 uptake in the globus pallidus when compared to the healthy control group.

"My colleagues and I were able to detect an elevated signal in the majority of evaluated PSP patients and could clearly discriminate the PSP group from healthy controls and disease controls," noted Brendel. "Importantly, PSP patients at early disease stages also revealed an elevated PI-2620 signal, which points at the suitability of this ligand as an early PSP biomarker. Detection of tau in PSP patients by PI-2620 could play a role in future anti-tau trials for this disease, and molecular imaging could serve to select the right patients for targeted therapies."

Eating a plant-based diet may be an effective treatment for Crohn's disease, according to a case study published in the journal Nutrients.

The case study followed a man in his late 20s who had been diagnosed with Crohn's disease after experiencing fatigue, bloating, episodic severe abdominal pain, nausea, and occasional ulcers for several years. His condition did not reach remission after more than a year of intravenous treatment.

During his second year of treatment, the patient removed all animal products and processed foods from his diet for a 40-day religious observation and experienced a total absence of symptoms. The patient decided to maintain the new dietary pattern--which was based on fruits, vegetables, whole grains, and legumes--and experienced a complete remission of Crohn's disease. Tests showed complete mucosal healing, and the patient was able to cease medications. He reports no relapses since.

"This case study offers hope for hundreds of thousands of people suffering from the painful symptoms associated with Crohn's disease," says study co-author Hana Kahleova, MD, PhD, director of clinical research at the Physicians Committee for Responsible Medicine.

Using current treatment regimens, only about 10 percent of traditionally managed Crohn's disease patients achieve long-term remission, and 50 percent of patients require surgery within 10 years of diagnosis.

The study authors note that plant-based diets are high in fiber, which promotes overall gut health. Fiber also feeds the healthy bacteria in the gut--which may offer a protective effect against Crohn's disease and other digestive problems. While more research is needed, previous studies have supported the conclusion that diets rich in plant proteins and whole foods may benefit Crohn's disease patients.

"This case study supports the idea that food really is medicine," adds Dr. Kahleova. "Not only does it show that eating a high-fiber, plant-based diet could help lead to Crohn's disease remission, but all the 'side effects' are good ones, including a reduced risk for heart disease, type 2 diabetes, and certain types of cancer."

The fly hasn't eaten for an entire day and it's starving. Finally, it finds a pile of edible gelatinous goo. It begins eating when suddenly a green light appears, and the food, which was far from delicious a moment ago, becomes irresistibly sweet. The fly, excited by the sudden improvement, eats with increased vigor. But its enthusiasm quickly wanes when the green light disappears and the flavour of the food reverts to its original blandness.

Reflecting on such an unusual situation, one might guess that it was the result of an added sweetener, or some sort of temporary delusion. But no, the answer lies within the realm of what might have been considered until recently to be science fiction.

"The fly's experience was very real. It was a virtual taste created by directly manipulating its taste neurons", says Carlos Ribeiro, head of the behavior and Metabolism lab at the Champalimaud Centre for the Unknown in Lisbon, Portugal. Together with his team, Ribeiro developed the optoPAD: a system that creates "virtual taste realities", in a way that can be flexibly paired with the fly's behavior. They describe this new technology in a scientific article published today June 21st in the journal eLife.

Creating virtual taste realities

The optoPAD combines two high-tech elements: the first is optogenetics, a powerful method that uses light to control the activity of neurons (quite literally to turn them "on" or "off"). For instance, the fly mentioned earlier was briefly enjoying more appetizing food because its sweet-sensing neurons were optogenetically activated by exposure to green light.

The second element of the optoPAD is an additional system, previously developed in the lab, called flyPAD. "The flyPAD uses touchscreen-type technology to monitor the fly's feeding behavior. Just like your phone is able to detect the touch of your finger on the screen, flyPAD is able to detect whenever the fly touches the food", explains José-Maria Moreira, one of the leading co-authors of study.

By combining flyPAD with optogenetics, the researchers were able to overcome one of the main challenges in the field of feeding research: precisely controlling taste sensations.

Unlike auditory or visual information, which can be altered instantaneously and independently of the animal's behavior, animals only experience taste information when they voluntarily touch the food with their tongue, or proboscis (in the case of the fly). "With optoPAD, we are constantly monitoring the behavior of the fly, to ensure that we optogenetically change the taste of the food precisely when the fly is in contact with it", Moreira explains.

Taste and beyond

In this study, which shows that the optoPAD is able to effectively pair active feeding with optogenetic manipulations, the researchers demonstrate that these virtual tastes have a very real effect on the behavior of the flies.

For instance, they are able to make the fly eat excessively by optogenetically activating sweet-sensing neurons; or make the fly stop eating all together, regardless of how hungry it is, by optogenetically activating bitter-sensing neurons.

For the researchers, manipulating taste was a good beginning, but it wasn't enough. "We developed the optoPAD, because we are interested in understanding how the brain makes one of the most fundamental decisions for our health: what food to eat", says Dennis Goldschmidt, another leading co-author, "but food choices do not only depend on taste, many parts of the brain are involved, so we wanted to ensure that optoPAD can be used to study the activity of neurons anywhere".

Since taste neurons are located in the mouth of the fly, which makes them easily accessible to the light needed for manipulation, the team chose a more difficult target: neurons at the center of the brain that are involved in jumping reactions.

The results were clear: "as we expected, optogenetic stimulation of these 'jumping' neurons, made the flies jump and stop feeding, showing that indeed, we can study any neuron, regardless of its location, in order to understand its role in the brain's feeding circuitry", says Goldschmidt.

Next steps

Though optoPAD seems like a fantastic way to improve one's nutrition without compromising taste, the researchers' goal is to use this technology to improve human life in a more fundamental way. "The food we eat affects all aspects of our lives, including aging, ability to reproduce, lifespan, mental state and mood", says Ribeiro. "Yet, how the brain controls food choice is still a mystery. The optoPAD can help us identify the neurons and genes that may have a direct impact on nutrition and hence our well-being in years to come."

The team is now gearing up to start a series of new experiments, and they are already freely sharing this exciting new technology with the scientific community by making all the blueprints and software freely available here: http://ribeirolab.org/optopad/. "We expect that the flexibility of the optoPAD will allow researchers not only to study feeding behavior but to also explore how flies adapt their behavior to complex environmental features, which will in turn may lead to the identification of novel neuronal circuits and computations", Ribeiro concludes.

San Francisco, CA - June 21, 2019 - New research has demonstrated the presence of S. aureus in 40% of the cell phones of students sampled at a university. S. aureus is a common cause of hospital and community-based infections and is currently considered an important pathogen because of its level of antibiotic resistance. The research, conducted at the Western University of São Paulo, Brazil, is presented at ASM Microbe, the annual meeting of the American Society for Microbiology.

Of the bacteria isolated, 85% were resistant to the antibiotic penicillin and 50% had the ability to adhere to surfaces. In addition, the presence of genes related to adhesion, antimicrobial resistance and toxins were present a high level. Samples were collected from 100 cell phones of students from the Biomedicine (20), Pharmacy (20), Dentistry (20), Nutrition (20), and Nursing (20) courses. The vast majority of the bacteria isolated belonged to students of the nursing course.

Nursing students are very likely to become carriers of S. aureus since clinical practice in hospital settings is part of their coursework and exposure to occupational hazards is inherent to this setting, which could favor the colonization and contamination of the surface of cell devices. Cell phones used in healthcare environments allow for the transmission of bacteria that harbor genes of virulence and resistance, contributing to increasing the infection rates as well as an increase in the morbidity/mortality from these infections.

"The widespread use of cell devices in hospitals and healthcare settings has raised major concerns about nosocomial infections, especially in areas requiring the highest standards of hygiene, such as the operating room," said Lizziane Kretli, Professor at the Western University of São Paulo, Brazil. Students in the health area attend practical classes and clinical stages where they have direct contact with samples, objects, and clinical environments containing pathogenic microorganisms.

Cell phones are an indispensable accessory in the professional and social life of a large part of the population. In the medical field they are considered an integral part of the life of health professionals and have improved communication, collaboration, and information sharing.

"In this context, cell phones may thus serve as a reservoir of bacteria known to cause nosocomial infections and could play a role in their transmission to patients through the hands of health professionals," said Kretli.

(Philadelphia, PA) - By adulthood, the heart is no longer able to replenish injured or diseased cells. As a result, heart disease or an event like a heart attack can be disastrous, leading to massive cell death and permanent declines in function. A new study by scientists at the Lewis Katz School of Medicine at Temple University (LKSOM), however, shows that it may be possible to reverse this damage and restore heart function, even after a severe heart attack.

The study, published June 21 in the print edition of the journal Circulation Research, is the first to show that a very small RNA molecule known as miR-294, when introduced into heart cells, can reactivate heart cell proliferation and improve heart function in mice that have suffered the equivalent of a heart attack in humans.

"In previous work, we discovered that miR-294 actively regulates the cell cycle in the developing heart," said Mohsin Khan, PhD, Assistant Professor of Physiology at the Center for Metabolic Disease Research at LKSOM. "But shortly after birth miR-294 is no longer expressed."

Dr. Khan and colleague Raj Kishore, PhD, Professor of Pharmacology and Medicine and Director of the Stem Cell Therapy Program in the Center for Translational Medicine at LKSOM, both senior investigators on the new study, wondered whether miR-294 could serve as a sort of fountain of youth for heart cells.

"The heart is very proliferative when miR-294 is expressed in early life," Dr. Kishore explained. "We wanted to see if reintroducing it into adult heart cells would turn them back to an embryonic-like state, allowing them to make new heart cells."

The researchers tested their idea in mice that had myocardial infarction (heart attack). Mice were treated with miR-294 continuously for two weeks after sustaining myocardial injury. Two months following treatment, the researchers observed noticeable improvements in heart function and a decrease in the area of damaged tissue. Examination of treated heart cells revealed evidence of cell cycle reentry, indicating that the cells had been reactivated, regaining the ability to produce new cells.

"The miR-294 treatment reawakened an embryonic signaling program in the adult heart cells," said Dr. Khan. "Because of this, the old heart cells were no longer quite like adult cells, but neither were they fully embryonic. In this in-between state, however, they had the ability to make new cells."

The researchers were able to control miR-294 expression, turning it on or off and thereby dictating the amount of proliferative activity in the heart.

Drs. Khan and Kishore plan next to replicate the study in a large animal model. They also want to gain a deeper understanding of what miR-294 is doing in the heart. "There is evidence that it does more than control the cell cycle," Dr. Khan said. "If it has multiple targets, we need to find them."

The promise of thermoelectric materials as a source of clean energy has driven the search for materials that can efficiently produce substantial amounts of power from waste heat.

Researchers reported a major step forward Friday, publishing in Science Advances the discovery of a new explanation for asymmetrical thermoelectric performance, the phenomenon that occurs when a material that is highly efficient in a form which carries a positive charge is far less efficient in the form which carries a negative charge, or vice versa.

Zhifeng Ren, M. D. Anderson Chair Professor of Physics at the University of Houston, director of the Texas Center for Superconductivity at UH and corresponding author on the paper, said they have developed a model to explain the previously unaddressed disparity in performance between the two types of formulations. They then applied the model to predict promising new materials to generate power using waste heat from power plants and other sources.

The researchers already knew thermoelectric efficiency depends on the performance of the material in both forms, known as "p-type" and "n-type" for carrying a positive and negative charge, respectively. But most materials either don't exist in both formulations or one type is more efficient than the other.

Promising New Material Synthesized

It is possible to build effective thermoelectric devices using just a p-type or n-type compound, but it is easier to design a device that contains both types; Ren said the best performance would come when both types exhibit similar properties.

The researchers synthesized one of the predicted materials, a zirconium-cobalt-bismuth compound, and reported a measured heat-to-electricity conversion efficiency of 10.6% at both the cold side, about 303 Kelvin, or about 86 degrees Fahrenheit, and the hot side, about 983 Kelvin (1,310 Fahrenheit) for both the p-type and the n-type.

Jun Mao, a post-doctoral researcher at UH and a first author of the report, said they determined the asymmetrical performance of some materials is linked to the fact that the charge moves at different rates in the two types of formulation. "If the charge movement of both the positive charge, for p-type, and the negative charge, for n-type, is similar, the thermoelectric performance of both types is similar," he said.

Knowing that, they were able to use the mobility ratio to predict performance of previously unstudied formulations.

"When the thermoelectric performance for one type of a material has been experimentally studied, while the other type has not yet been investigated, it is possible to predict the ZT by using the identified relationship between the asymmetry and weighted mobility ratio," the researchers wrote. ZT, or the figure of merit, is a metric used to determine how efficiently a thermoelectric material converts heat to electricity.

New Model Predicts Highly Efficient Materials

Hangtian Zhu, a post-doctoral researcher at UH and the report's other first author, said the next step is determining how to formulate the corresponding type of material, once a material with a high efficiency in either p-type or n-type is found.

That can require experimentation to determine the best dopant - researchers tweak performance by adding a tiny amount of an additional element to the compound, known as "doping" - to improve performance, Zhu said.

That's where the new understanding of asymmetrical performance comes in. Zhu said by predicting which compounds will have high performance in both types, researchers are encouraged to continue looking for the best combination, even if early efforts did not succeed.

New research by neuroscientists from the University of Sussex shows that drinking only one pint of beer or large glass of wine is enough to significantly compromise a person's sense of agency.

Sense of agency is the feeling of being in control of our actions. It is an important aspect of human social behaviour, as it implies knowledge of the consequences of those actions.

This new study, Effect of alcohol on the sense of agency in healthy humans, is the first to test the effect of alcohol on sense of agency. The study focused on low doses of alcohol, typically consumed during social drinking, that do not produce a large impairment of behaviour. Until now, research has mostly focused on the loss of inhibitory control produced by obvious drunkenness, characterised by impulsivity, aggression, and risky behaviour.

Dr Silvana De Pirro, lead author of the research paper, said: "Our study presents a compelling case that even one pint of beer is enough to significantly compromise a person's sense of agency. This has important implications for legal and social responsibility of drivers, and begs the question: are current alcohol limits for driving truly safe?"

Explaining how the study was conducted, Dr De Pirro said: "Measuring a person's sense of agency is tricky. When people are explicitly asked to tell how in control they feel, their answers are affected by several cognitive biases, such as poor introspection, the desire to conform to researchers' expectations, or even the inability to understand the question correctly."

Sussex researchers relied therefore on an indirect measure called 'intentional binding', which has been developed to investigate the unconscious mechanisms of 'volition'. When physical stimuli (such as sounds or lights) follow voluntary actions (such as moving a finger or a hand), people judge actions as occurring later and stimuli as occurring earlier than in reality, hence 'binding' the two. The neural mechanisms responsible for this phenomenon are thought to participate in creating the sense of agency.

In the experiments, subjects drank a cocktail containing doses of alcohol proportional to their BMI to produce blood alcohol concentrations within the legal limits for driving in England and Wales. These doses of alcohol, corresponding to one or two pints of beer, produced tighter binding between voluntary actions and sensory stimuli. This suggests that small amounts of alcohol might exaggerate the sense of agency, leading to overconfidence in one's driving ability and to inappropriate, potentially dangerous behaviour.

Professor Aldo Badiani, Director of the Sussex Addiction Research and Intervention Centre (SARIC), said: "It's important to note that in our experiments, all the participants stayed within the legal alcohol limit for driving in England, Wales, the US and Canada. And yet we still saw an impairment in their feeling of being in control.

"In England, Wales and North-America, the argument to lower the limit has much momentum. The results of our study support the implementation of such a change in the law."

The legal limit for driving in England and Wales is currently 80 mg/100 ml. The legal limit for driving in Scotland and most European countries is 50 mg/100 ml.

A nanomaterial made from phosphorus, known as phosphorene, is shaping up as a key ingredient for more sustainable and efficient next-generation perovskite solar cells (PSCs).

PSCs which are one of the fastest developing new solar technologies and can achieve efficiencies comparable to more commonly used commercially available silicon solar cells.

For the first time, an international team of clean chemistry researchers led by Professor Joseph Shapter and Flinders University, has made very thin phosphorene nanosheets for low-temperature PSCs using the rapid shear stress of the University's revolutionary vortex fluidic device (VFD).

"Silicon is currently the standard for rooftop solar, and other solar panels, but they take a lot of energy to produce them. They are not as sustainable as these newer options," says adjunct Professor Shapter, now at University of Queensland.

"Phosphorene is an exciting material because it is a good conductor that will absorb visible light. In the past most non-metallic materials would have one property but not both," he says.

"We've found exciting new way to convert exfoliated black phosphorus into phosphorene which can help produce more efficient and also potentially cheaper solar cells," says Dr Christopher Gibson, from the College of Science and Engineering at Flinders University.

"Our latest experiments have improved the potential of phosphene in solar cells, showing an extra efficiency of 2%-3% in electricity production."

Research into making high quality 2D phosphorene in large quantities- along with other future materials such as graphene - are paving the way to more efficient and sustainable production with the use of the SA-made VFD, near-infrared laser light pulses, and even an industrial-scale microwave oven.

"The work with phosphorene is exploring the addition of different atoms to the matrix which is showing very promising results in catalysis, particularly in the area of water splitting to produce hydrogen and oxygen," says Professor Shapter.

With the ability to artificially produce perovskite structures, commercial viability is at the threshold and not too far away once the cells can be successfully scaled up. Meanwhile research around the world continues to look for ways to improve and optimise perovskite cell performance.

Often, the findings of fundamental scientific research are many steps away from a product that can be immediately brought to the public. But every once in a while, opportunity makes an early appearance.

Such was the case for a team from the Department of Energy's Joint BioEnergy Institute (JBEI), whose outside-the-box thinking when investigating microbe-based biomanufacturing led straight to an eco-friendly production platform for a blue pigment called indigoidine. With a similar vividly saturated hue as synthetic indigo, a dye used around the world to color denim and many other items, the team's fungi-produced indigoidine could provide an alternative to a largely environmentally unfriendly process.

"Originally extracted from plants, most indigo used today is synthesized," said lead researcher Aindrila Mukhopadhyay, who directs the Host Engineering team at JBEI. "These processes are efficient and inexpensive, but they often require toxic chemicals and generate a lot of dangerous waste. With our work we now have a way to efficiently produce a blue pigment that uses inexpensive, sustainable carbon sources instead of harsh precursors. And so far, the platform checks many of the boxes in its promise to be scaled-up for commercial markets."

Importantly, these commercial markets already have considerable demand for what the scientists hope to supply. After meeting with many key stakeholders in the textile industry, the team found that many companies are eager for more sustainably sourced pigments because customers are increasingly aware of the impacts of conventional dyes. "There seems to be a shift in society toward wanting better processes for creating everyday products," said Maren Wehrs, a graduate student at JBEI and first author of the paper describing the discovery, now published in Green Chemistry. "That's exactly what JBEI is trying to do, using tools derived from biological systems - it just so happens that our engineered biological platform worked very well."

The story began when the team set out to test how well a hardy fungi species called Rhodosporidium toruloides could express nonribosomal peptide synthetases (NRPSs) - large enzymes that bacteria and fungi use to assemble important compounds. The scientists examined this fungi's NRPS expression capability by inserting a bacterial NRPS into its genome. They chose an NRPS that converts two amino acid molecules into indigoidine - a blue pigment - to make it easy to tell if the strain engineering had worked. Quite simply, when it did, the culture would turn blue.

Going into this experiment, indigoidine itself was not the main interest for the team. Instead, they were focused on the larger picture: exploring how the assembly line functionality of these enzymes could be harnessed to create biosynthetic manufacturing pathways for valuable organic compounds, such as biofuels, and assessing whether or not the fungi represented a good host species for the production of these compounds. But when they cultivated their engineered strain, and saw just how blue the culture was, they knew something incredible had happened.

With an average titer of 86 grams of indigoidine per liter of bioreactor culture, the yield of the strain - which they named Bluebelle - is by far the highest that has ever been reported. (Other research groups, including the JBEI team, have synthesized indigoidine using different host microbes.) Adding to the weight of the achievement, the record-breaking yield was obtained from a culture process that uses nutrient and precursor inputs sourced from sustainable plant material. Previous pathways required considerably more expensive inputs yet made about one tenth the amount of indigoidine.

Beyond the potential applications of indigoidine, the study succeeded in its original goal of providing a potential production pathway for other NRPSs - something that is much more valuable than any single product. These complex enzymes have multiple subunits that each perform a distinct and predictable action in assembling a compound out of smaller molecules. Scientists at JBEI and beyond are keen to engineer enzymes that use NRPSs' Lego block-like features to produce advanced bioproducts that are currently hard to make.

"A big challenge is to get a microbe to efficiently express such enzymes. This host has huge potential to fulfill that need," said Mukhopadhyay.

The team's next steps will be to characterize how indigoidine could be used as a dye and to dig deeper into the capabilities of R. toruloides.

This work was made possible by the expertise of multiple groups, including John Gladden from Sandia National Laboratories, who leads JBEI's Fungal Biotechnology team, and Berkeley Lab's Advanced Biofuels and Bioproducts Process Development Unit (ABPDU). The other researchers included Yuzhong Liu, Lukas Platz, Jan-Philip Prahl, Jadie Moon, Gabriella Papa, Eric Sundstrom, Gina Geiselman, Deepti Tanjore, Todd Pray, Jay Keasling, and Blake Simmons. JBEI is funded by the Department of Energy Office of Science. ABPDU is funded by the DOE Office of Energy Efficiency and Renewable Energy.

It's easy to think of cities as being the enemy of nature. When we talk about escaping the skyscrapers and car horns, we have visions of breathing in fresh mountain air while hiking through forests in mind. But for Monarch butterflies, the busy cities we know could be key to their survival.

Monarchs, with their striking orange and black wings, are some of the most well-known butterflies in the US. But the Monarch population has declined over 80% in the last twenty years, and scientists warn that as milkweed--the only plant Monarchs can lay their eggs on--continues to disappear across the United States, these butterflies could disappear too. Two new studies in the journal Frontiers of Ecology and Evolution show that one of the most important things we can do to save the Monarchs is plant milkweed in cities.

"Metropolitan areas actually matter for wildlife conservation, and that's especially true for pollinators like the Monarch that can survive with very small patches of habitat," says Abigail Derby Lewis, a senior conservation ecologist at the Field Museum and lead author of the paper Does Nature Need Cities? "There's an assumption that cities are not important places for plants and animals, but that's because no one had looked at these landscapes in a systematic way, or at the collective impact from many small-scale plantings across large urban geographies."

"This is the first study that estimates the amount of habitat in cities available to Monarchs and other pollinators, and how much potential there is to add more," says Mark Johnston, a conservation ecologist at the Field and lead author of the team's second paper. This paper dives deep into the science of quantifying the role that large urban areas play in supporting Monarchs while mapping out opportunities to plant more by providing planning tools to guide Monarch conservation efforts in cities.

In order to discover how much milkweed cities could contribute, the research team used field research coupled with high resolution spatial images to map where milkweed already occurs across large metropolitan regions and where there's potenital to add. For example, while there's not much milkweed found in residential areas, yards represent an enormous opportunity to boost milkweed numbers because of how many homes there are.

"This approach to examining metropolitan landscapes allows us to 'see' cities in a way we haven't been able to before, and this enables us to get a better estimate of how much potential space there is to create habitat," says Johnston. Researchers have estimated that saving Monarchs would entail planting 1.8 billion stems of milkweed. To put that in perspective, if we planted one stem of milkweed per square foot, it would cover an area about the size of Washington, DC. But a lot of that habitat space is available in America's cities. "We think that cities could support 15 to 30 percent of the milkweed that's needed to save Monarchs," says Johnston.

"Urban areas are only three percent of US landmass," adds Derby Lewis. "Conservationists and urban planners were shocked to learn what an outsize implication cities could have for Monarch conservation."

"We've looked at cities from a Monarch's point of view by identifying the best places and most effective ways to engage different land owners to transform low-quality green space, like lawn grass, into high-quality homes for these butterflies" says Derby Lewis. "This perspective also helps us understand the role cities can play to support a wide range of other wildlife, including ones that aren't as beloved by the public as butterflies. Beetles are incredible pollinators, but a campaign to 'plant for beetles' probably wouldn't go anywhere. By helping Monarch butterflies, we're helping other pollinators, which are on the decline. Many of our main crops need pollinators to pollinate them--things like apples and avocados."

Just because urban dwellers can plant milkweed, however, doesn't always mean they will. In some regards, researchers say the most interesting effect of the study is yet to come. While urban landscapes have the capacity to help a whole suite of species by creating green spaces that are teeming with food and shelter for these small but mighty pollinators, there are some challenges to face in order to make that a reality. A critical one is moving toward a public perception that milkweed and native flowers are acceptable and beautiful elements in home landscaping. "Certainly having the term 'weed' in the name of milkweed--which isn't a weed--has not helped the reputation of these superstar native plants," says Derby Lewis.

Shifting societal norms of what is desirable in neighborhood gardens is something both Derby Lewis and Johnston were passionate about. Gardening has been a favorite pastime for decades, and is one of the most accessible ways for people to feel connected to the earth. To give gardeners and non-gardeners alike another purpose for their planting is an important message of this study. "I would encourage people to question the grassy lawns that dominate our urban landscape--could we plant something else that would provide habitat for Monarchs and other wildlife?" asks Johnston.

As once unoccupied land continues to develop, we're reminded that nature can be found everywhere and in many forms, and every patch of land can be valuable. As with most things, it takes a village - and a city.