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Not enough progress has been made to address physical inactivity worldwide, with adolescents and people living with disabilities (PLWD) among the least likely populations to have the support needed to meet the World Health Organization (WHO)'s physical activity guidelines. Global efforts to improve physical activity have stalled, with overall deaths caused by physical activity remaining at more than 5 million people per year. [1]

Physical inactivity is linked to an increased risk of non-communicable diseases (NCDs) such as heart disease, diabetes, and some cancers and costs at least $54 billion per year in direct health care costs of which $31 billion is paid by the public sector. The slow progress to improve physical activity worldwide has been exacerbated by the COVID-19 pandemic, with lockdowns likely associated with overall less physical activity worldwide. In addition, inactive people and those with NCDs are far more likely to be hospitalized or die if they develop COVID-19.

These findings come from a new three-paper Series published in The Lancet and launched ahead of the postponed 2020 Olympics in Tokyo, Japan. The authors call for immediate and urgent action to prioritize research and public health measures to improve physical activity worldwide, and ensure physical activity is built into every day lives.

More progress needed to improve physical activity among adolescents (paper 1)

Despite the growing number of young people diagnosed with non-communicable diseases (NCDs), including cardio-metabolic and mental health disorders, the authors note that research on adolescent physical activity is limited.

Global analysis shows that 80% of school-going adolescents are failing to meet the WHO recommended guidelines of 60 minutes of physical activity per day, with little progress made since 2012. In addition, 40% of adolescents never walk to school and 25% sit for more than 3 hours per day in addition to sitting at school and for homework.

The researchers also examined screen time in adolescents in 38 European countries and found that 60% of boys and 56% of girls spent two hours or more a day watching television. In addition, 51% of boys and 33% of girls spent two hours a day or more playing video games. However, little is known about how this impacts their cardio-metabolic and mental health.

Lead author of the paper, Dr Esther van Sluijs of the University of Cambridge, UK says, "We desperately need to explore both the short- and long-term consequences physical inactivity has on adolescents, and identify effective ways of promoting increases in physical activity, especially in light of the COVID-19 pandemic. Virtual schooling and social distancing have drastically reduced physical activity and increased use of screens, and the consequences of these changes could last a lifetime." [2]

She adds, "Adolescents make up nearly one quarter of the world's population, and by ensuring that they grow up in social and physical environments that are supportive of physical activity, we are helping to change their health right now, improve their future health, and positively influence the health of the next generation." [2]

More must be done to empower the rights of people living with disabilities to participate in physical activity (paper 2)

Physical activity can provide a range of physical and mental health benefits for the 1.5 billion people worldwide living with a physical, mental, sensory, or intellectual disability. However, researchers found that PLWD are 16-62% less likely to meet physical activity guidelines and are at higher risk of serious health problems related to inactivity, such as cardiovascular disease, diabetes, and obesity.

The proportion of adults with disabilities living in high-income countries who meet physical activity guidelines range from 21% to 60%, in contrast to estimates ranging from 54% to 91% for adults without disabilities. The magnitude of disparities in physical activity for PLWD varies across disability types and is greatest for those with multiple impairments.

In addition, researchers found that any amount of physical activity, even if less than the WHO-recommended 150 minutes per week is beneficial to PLWD. Benefits included improving cardiovascular health, muscular strength, function skills, and mental health.

The study authors call for physical activity action plans worldwide to be adequately resourced, monitored, and implemented to truly advance the fundamental rights of PLWD to fully participate in physical activity.

"Interest in disability sport continues to grow and could be a key driver in promoting more empowerment, participation, and inclusion for PLWD. But we also need more research focused on PLWD as well as cohesive, targeted policies and guidelines to ensure the rights of PLWD are upheld and allow for full and effective participation in physical activity," says Dr Kathleen Martin Ginis of the University of British Columbia, Canada, and lead author of the paper. [2]

The authors highlight that 80% of people with disabilities live in low-income and middle-income countries. However, in this review, virtually all available population data on physical activity in people living with a disability (PLWD) comes from high-income countries in North America and northwest Europe, indicating an urgent need for more research into physical activity for PLWD on a global scale.

Olympics must provide a legacy for health that lasts (paper 3)

Mass sporting events, including the Olympic Games, offer an opportunity to promote physical activity for global populations - including adolescents and PLWD. However, study authors found that Olympic Games had a minimal impact on physical activity in host cities and are a missed opportunity to improve health at the population level.

Researchers found there has been no measurable change in participation in sports either immediately before or after the Olympic Games [figure 1]. This was true even after the Olympic Games initiated the global impact project in 2001, which suggested that cities collect indicator data before and after the Olympic Games that specifically include legacy information on grassroots sports participation. These findings suggest that more planning and greater public health efforts are needed to generate a legacy of more physical activity following the Olympics or other mass sporting events.

"The Olympics and other mass sporting events are a missed opportunity to change health and physical activity at the population level not only in the host city or country but around the world. The Olympics provide a global stage to get people interested in and excited about physical activity. The challenge is how to translate that enthusiasm into sustained public health programs that are achievable and enjoyable for the general public," says lead author of the paper, Prof Adrian Bauman of the University of Sydney, Australia. [2]

The authors call for pre-and post-event planning and partnerships between local and national governments and the International Olympic Committee and a thorough evaluation framework of physical activity host cities and countries to build a legacy that will lead to more physical activity and improve public health.

Physical activity: an essential human need beyond and independent of COVID-19.

Writing in a linked Editorial, Dr Pam Das, Senior Executive Editor of The Lancet says "The pandemic provides a powerful catalyst to advocate for physical activity...Exercise during lockdowns was considered an essential activity by many governments worldwide--physical activity was seen to be as essential as food, shelter, and seeking medical care. Early government campaigns during COVID-19 encouraged the public to go out and exercise. Why then can governments not commit to promoting physical activity as an essential human need beyond and independent of COVID-19?

"The much heightened public awareness about health, presents an opportunity to focus on the benefits of being healthy rather than managing disease. One goal should be to integrate physical activity into the way people lead their lives every day such that the physically active choices, which are often the healthier and more environmentally friendly ones, become the default. Using public transport, active travel, mandatory physical education in schools, and after-school activities are a few possibilities. The pandemic showed how easy it is to go for a 30 min daily walk. By advocating levels of physical activity that people can reasonably integrate into their lives, such as walking, expectations can be managed. Set the bar too high, and people will do nothing. But with reasonable targets, they might just get moving."

Two years on from its pledge to make England smoke free by 2030, the UK government has failed to deliver on the policies it promised to deliver this ambition, say a group of leading doctors, professional bodies and charities in The BMJ today.

In an open letter to the Prime Minister and Secretary of State for health, they say smoking is likely to have killed more people last year than covid-19 and it will carry on doing so for many years to come unless the government takes action.

They call for a US-style 'polluter pays' levy on tobacco manufacturers to fund the strategy, saying "the time has come to make the tobacco manufacturers pay to end the epidemic they and they alone have caused."

The rate of decline in smoking in the years leading up to 2019 was not sufficient to deliver this ambition, they explain. In the last two years it is estimated that over 200,000 children under 16 have started to smoke, two thirds of whom will go on to become regular smokers.

Delivering the Smokefree ambition "would play a major role in achieving Government manifesto commitments to increase healthy life expectancy by five years by 2035, while reducing inequalities and levelling up the nation," they write.

The blueprint to achieve this is laid out in the All Party Parliamentary Group (APPG) on Smoking and Health recommendations for the forthcoming Tobacco Control Plan, but it needs to be properly funded.

The APPG report sets out how a levy on manufacturers could raise £700 million in year one alone, without the costs being passed on to smokers, now that we have left Europe. "This could pay for delivery of the Tobacco Control Plan, and provide additional funding that public health desperately needs."

They point out that in 2019 Imperial Tobacco made £71 for every £100 in sales. "These are extreme profits, many times higher than those made by other consumer product manufacturers," they say. "The time has come to make the tobacco manufacturers pay to end the epidemic they and they alone have caused."

Chestnut Hill, Mass. (7/21/2021) - Researchers have discovered a "layer" Hall effect in a solid state chip constructed of antiferromagnetic manganese bismuth telluride, a finding that signals a much sought-after topological Axion insulating state, the team reports in the current edition of the journal Nature.

Researchers have been trying to find evidence of a topological Axion insulating (TAI) state and developed some candidate materials based on theoretical calculations. The layered Hall effect represents the first clear experimental evidence of the state, a feature bound by the laws of quantum physics, according to Boston College Assistant Professor of Physics Qiong Ma, a senior researcher on the project, which included 36 scientists from universities in the U.S., Japan, China, Taiwan, Germany, and India.

Researchers believe that when it is fully understood, TAI can be used to make semiconductors with potential applications in electronic devices, Ma said. The highly unusual properties of Axions will support a new electromagnetic response called the topological magneto-electric effect, paving the way for realizing ultra-sensitive, ultrafast, and dissipationless sensors, detectors and memory devices.

At the center of this line of inquiry among physicists and materials scientists are Axions, weakly-interacting particles first postulated by theorists more than 30 years ago, Ma said. They are one of the primary candidates for Dark Matter, a mysterious form of matter thought to account for approximately 85 percent of the universe.

While the search for Axions in high-energy physics is actively ongoing, it has been recently proposed that Axions can be realized as quasi-particles in solid state materials. The prime candidate as the place to locate Axions is in a quantum TAI material, where researchers suggest Axions exist as low-energy electronic excitations, Ma said.

"We set out to search for the topological Axion insulating state in a carefully designed quantum device made of even-number-layered MnBi2Te4 - or manganese bismuth telluride," Ma said. "Previous studies have demonstrated the insulating state, namely, very large resistance, which is, however, true for any insulator. We wanted to further demonstrate properties that are unique to Axion insulators and do not exist in regular insulators, such as diamond."

The material forms a two-dimensional layered crystal structure, which allowed Ma and her colleagues to mechanically exfoliate atom-thick flakes using cellophane tape that can be found in most drug stores and supermarkets. Thin flake structures with even numbers of layers were proposed to be an Axion insulator.

Ma worked closely with fellow Boston College physicists Brian Zhou and Kenneth Burch. Zhou used a unique quantum technique to detect the magnetism of MnBi2Te4. Burch has a unique glovebox facility used to process the sample in an inert environment.

"We first characterized the layer number with optical methods and then performed electrical transport measurements, such as measuring the sample resistance under different conditions, including varying electric field, magnetic field and environmental temperature," Ma said.

The researchers found the Hall effect, a well known law of physics where electrons travel at an angle from the axis under the influence of an applied magnetic field. But in this case, these electrons were traveling without such assistance, Ma said. The key was the materials' topology, or the quantum characteristics of its electrons and the waves in which they function.

"We observed a novel property for electrons travelling across this material in its Axion insulating state: The electrons do not travel in a straight line; instead, they deflect to the transverse direction. This effect was usually only observed under a large magnetic field, known as the Hall effect," Ma said. "But here, the deflection occurs due to inherent topology of the materials and without external magnetic field. More interestingly, the electrons deflect to opposite sides on the top and bottom layers. Therefore, we coined it as the layer Hall effect. The layer Hall effect serves as a distinct signature of the topological Axion insulating state, which will not happen in regular insulators."

Ma, whose research on the project is supported by the U.S. Department of Energy, said the team was surprised to find that the topological Axion insulating state and the layer Hall effect can be effectively controlled by the so-called Axion field, which is the product of applying both an electric field and a magnetic field.

"This means that whether the electrons deflect to the left or to the right on the top and bottom layers can be switched by the collective application of the electrical and magnetic fields," Ma said. "A single field is not able to switch one situation to the other."

Harvard University Assistant Professor of Chemistry Suyang Xu, a lead author of the report, added, "We are very excited about this work because it demonstrates the first realistic platform for the topological Axion insulator state."

Ma said the identification of the topological Axion insulating state leads to the next step of searching for signatures of the defining Axion dynamics in this system, which is known as the topological magnetoelectric effect (ME).

"The topological ME effect is a fundamentally new mechanism to convert electricity to magnetism, or vice versa, without lost energy, and has great potential to realize ultra-energy-efficient spintronic and memory devices," said Ma.

To demonstrate such will require further optimization of the material quality, the geometry of the device, and expanded experimental capabilities, Ma said.

Scientists at St. Jude Children's Research Hospital have found a link between post-cancer treatment frailty and neurocognitive decline in young adult childhood cancer survivors. A paper on this work was published today in the Journal of Clinical Oncology.

Though frailty is often associated with the elderly, 8% of young adult childhood cancer survivors meet the criteria for frailty. This study confirms that those who undergo childhood cancer treatment can experience frailty, which can create an early onset of neurocognitive decline in young adults. This study will help with further research to prevent such neurocognitive decline.

"We think this is going to put more attention on this accelerated aging phenotype in young adult survivors," said first author AnnaLynn Williams, Ph.D., St. Jude Epidemiology and Cancer Control. "It's going to make it a bit easier for us to identify the survivors most at risk for neurocognitive decline.

"We can use this information, and the rest of our frailty research, to design a broad intervention that might simultaneously help us improve frailty in survivors as well as neurocognitive functioning," Williams said.

More important than previously recognized

Cancer-related neurocognitive impairment is present in up to 35% of childhood cancer survivors. It can influence all aspects of their lives, including their physical functioning and daily activities.

Over the span of five years, researchers found that survivors who experienced treatment-related frailty had significantly greater declines in memory, attention, processing speed and other functions as compared to survivors who did not experience frailty.

The intensive chemotherapies that young adult survivors experience during their childhood years are known to contribute to health problems later in life. Frailty is just one such late effect of care.

This study and many others relied on data from the St. Jude Lifetime Cohort study (St. Jude LIFE). This study brings long-term childhood cancer survivors back to St. Jude for regular health screenings throughout their adult lives. To date, more than 4,300 participants and 580 controls have undergone comprehensive health evaluations tracking a wide range of health outcomes, such as cardiac, reproductive, neuromuscular, neurocognitive and psychosocial function, among others.

"Our work has shown that childhood cancer survivors are at an increased risk of frailty," said corresponding author Kirsten Ness, Ph.D., of St. Jude Epidemiology and Cancer Control. "Since frailty has now been shown to contribute to neurocognitive deficits among other health problems, it is increasingly apparent that addressing frailty may aid this patient population.

"This is why St. Jude LIFE studies are so important," Ness continued. "It allows us to identify risk factors for poor health outcomes in the the next generation of children with cancer so we can provide interventions to help them."

One of the major challenges in modern cancer therapy is the adaptive response of cancer cells to targeted therapies: initially, these therapies are very often effective, then adaptive resistance occurs, allowing the tumor cells to proliferate again. Although this adaptive response is theoretically reversible, such a reversal is hampered by numerous molecular mechanisms that allow the cancer cells to adapt to the treatment. The analysis of these mechanisms is limited by the complexity of cause and effect relationships that are extremely difficult to observe in vivo in tumor samples. In order to overcome this challenge, a team from the University of Geneva (UNIGE) and the University Hospitals of Geneva (HUG), Switzerland, has used information theory for the first time, in order to objectify in vivo the molecular regulations at play in the mechanisms of the adaptive response and their modulation by a therapeutic combination. These results are published in the journal Neoplasia.

Adaptive response limits the efficiency of targeted therapies used to fight the development of tumors: after an effective treatment phase that reduces the tumor size, an adaptation to the used molecule occurs that allows the tumor cells to proliferate again. "We now know that this resistance to treatment has a large reversible component that does not involve mutations, which are an irreversible process", explains Rastine Merat, a researcher in the Department of Pathology and Immunology at the UNIGE Faculty of Medicine, the head of the Onco-Dermatology Unit at the HUG and the principal investigator of the study.

Research confronted with the complexity of biological regulations

In order to prevent resistance to targeted therapies, scientists need to understand the molecular mechanisms of the adaptive response. "These mechanisms may involve variations in gene expression, for example", explains Rastine Merat. It is then necessary to modify or prevent these variations by means of a therapeutic combination that blocks the consequences or even prevents them. One challenge remains: the description of these mechanisms and their modulation under the effect of a therapeutic combination is very often carried out on isolated cultured cells and not validated in tumor tissue in the body. "This is essentially due to the difficulty of objectifying these mechanisms, which may occur in a transient manner and only in a minority of cells in tumor tissues, and above all which involve non-linear cause and effect relationships", explains the Geneva researcher.

Applying information theory to tumors

To counter these difficulties, the UNIGE and HUG team came up with the idea of using information theory, more specifically by quantifying mutual information. This approach has previously been used in biology, mainly to quantify cell signaling and understand genetic regulation networks. "This statistical method makes it possible to link two parameters involved in a mechanism by measuring the reduction in the uncertainty of one of the parameters when the value of the other parameter is known", simplifies Rastine Merat.

Practically, the scientists proceed step by step: they take biopsies of tumors (in this case melanomas) in a mouse model at different stages of their development during therapy. Using immunohistochemical analyses - i.e. tumor sections - they measure, using an automated approach, the expression of proteins involved in the mechanism at play in the adaptive response. "The proposed mathematical approach is easily applicable to routine techniques such as immunohistochemistry and makes it possible to validate in vivo the relevance of the mechanisms under study, even if they occur in a minority of cells and in a transient manner", the Geneva researcher explains. Thus, scientists can not only validate in the organism the molecular mechanisms they are studying, but also the impact of innovative therapeutic combinations that result from the understanding of these mechanisms. "Similarly, we could use this approach in therapeutic trials as a predictive marker of response to therapeutic combinations that seek to prevent adaptive resistance", he continues.

A method suitable for all types of cancer

"This method, developed in a melanoma model, could be applied to other types of cancer for which the same issues of adaptive resistance to targeted therapies occur and for which combination therapy approaches based on an understanding of the mechanisms involved are under development", concludes Rastine Merat.

Rome (Italy), July 21st, 2021 - The remarkable structural properties of the basket sponge (E. aspergillum) might seem fathoms removed from human-engineered structures. However, insights into how the organism's latticework of holes and ridges influences the hydrodynamics of seawater in its vicinity could lead to advanced designs for buildings, bridges, marine vehicles and aircraft, and anything that must respond safely to forces imposed by the flow of air or water.

While past research has investigated the structure of the sponge, there have been few studies of the hydrodynamic fields surrounding and penetrating the organism, and whether, besides improving its mechanical properties, the skeletal motifs of E. Aspergillum underlie the optimization of the flow physics within and beyond its body cavity.

A collaboration across three continents at the frontiers of physics, biology, and engineering led by
Giacomo Falcucci (from the Tor Vergata University of Rome and Harvard University), in collaboration with Sauro Succi (Italian Institute of Technology) and Maurizio Porfiri (Tandon School of Engineering, New York University) applied super computational muscle and special software to gain a deeper understanding of these interactions, creating a first-ever simulation of the deep-sea sponge and how it responds to and influences the flow of nearby water.

The work, "Extreme flow simulations reveal skeletal adaptations of deep-sea sponges" published in the journal Nature, revealed a profound connection between the sponge's structure and function, shedding light on both the basket sponge's ability to withstand the dynamic forces of the surrounding ocean and its ability to create a nutrient-rich vortex within the body cavity "basket."

"This organism has been studied a lot from a mechanical point of view because of its amazing ability to deform substantially in spite of its brittle, glassine structure," said first author Giacomo Falcucci of Tor Vergata University of Rome and Harvard University. "We were able to investigate aspects of hydrodynamics to understand how the geometry of the sponge offers a functional response to fluid, to produce something special with respect to interaction with water"

"By exploring the fluid flow within and outside the body cavity of the sponge, we uncovered the footprints of an expected adaptation to the environment. Not only does the sponge's structure contribute to a reduced drag, but also it facilitates the creation on low-velocity swirls within the body cavity that are used for feeding and reproduction" added Porfiri, a co-author of the study.

The structure of E. Aspergillum, reproduced by co-author Pierluigi Fanelli, of the University of Tuscia, Italy, resembles a delicate glass vase in the form of a thin-walled, cylindrical tube with a large central atrium, siliceous spicules -- thus their commonly used appellation, "glass sponges". The spicules are composed of three perpendicular rays, giving them six points. The microscopic spicules "weave" together to form a very fine mesh, which gives the sponge's body a rigidity not found in other sponge species and allows it to survive at great depths in the water column.

To understand how Venus flower basket sponges do this, the team made extensive use of the Marconi100 exascale-class computer at the CINECA high performance computing center in Italy, which is capable of creating comprehensive simulations using billions of dynamic, temporospatial data points in three dimensions.

The researchers also exploited special software developed by study co-author Giorgio Amati, of SCAI (Super Computing Applications and Innovation) at CINECA, Italy. The software enabled super computational simulations based on Lattice Boltzmann methods, a class of computational fluid dynamics methods for complex systems that represents fluid as a collection of particles and tracks the behavior of each of them.

The in-silico experiments, featuring approximately 100 billion virtual particles, reproduced the hydrodynamic conditions on the deep-sea floor where E. Aspergillum lives. Results processed by Vesselin K. Krastev at Tor Vergata University of Rome allowed the team to explore how the organization of holes and ridges in the sponge improves its ability to reduce the forces applied by moving seawater (a mechanical engineering question formulated by Falcucci and Succi), and how its structure affects the dynamics of flow within the sponge body cavity to optimize selective filter feeding and gamete encounter for sexual reproduction (a biological question formulated by Porfiri and a biologist expert on ecological adaptations in aquatic creatures, co-author Giovanni Polverino from the Centre for Evolutionary Biology at The University of Western Australia, Perth).

"This work is an exemplary application of discrete fluid dynamics in general and the Lattice Boltzmann method, in particular," said co-author Sauro Succi of the Italian Institute of Technology and Harvard University. Sauro Succi is internationally recognized as one of the fathers of the Lattice Boltzmann Method. "The accuracy of the method, combined with access to one of the top super computers in the world made it possible for us to perform levels of computation never attempted before, which shed light on the role of fluid flows in the adaption of living organisms in the abyss."

"Our investigation of the role of the sponge geometry on its response to the fluid flow, has a lot of implications for the design of high-rise buildings or, really, any mechanical structure, from skyscrapers to low-drag novel structures for ships, or fuselages of airplanes," said Falcucci. "For example, will there be less aerodynamic drag on high-rise buildings built with a similar latticework of ridges and holes? Will it optimize the distribution of forces applied? Addressing these very questions is a key objective of the team."

At low temperatures, certain materials lose their electrical resistance and conduct electricity without any loss - this phenomenon of superconductivity has been known since 1911, but it is still not fully understood. And that is a pity, because finding a material that would still have superconducting properties even at high temperatures would probably trigger a technological revolution.

A discovery made at TU Wien (Vienna) could be an important step in this direction: A team of solid-state physicists studied an unusual material - a so-called "strange metal" made of ytterbium, rhodium and silicon. Strange metals show an unusual relationship between electrical resistance and temperature. In the case of this material, this correlation can be seen in a particularly wide temperature range, and the underlying mechanism is known. Contrary to previous assumptions, it now turns out that this material is also a superconductor and that superconductivity is closely related to strange metal behaviour. This could be the key to understanding high-temperature superconductivity in other classes of materials as well.

Strange metal: linear relationship between resistance and temperature

In ordinary metals, electrical resistance at low temperatures increases with the square of the temperature. In some high-temperature superconductors, however, the situation is completely different: at low temperatures, below the so-called superconducting transition temperature, they show no electrical resistance at all, and above this temperature the resistance increases linearly instead of quadratically with temperature. This is what defines "strange metals".

"It has therefore already been suspected in recent years that this linear relationship between resistance and temperature is of great importance for superconductivity," says Prof. Silke Bühler-Paschen, who heads the research area "Quantum Materials" at the Institute of Solid State Physics at TU Wien. "But unfortunately, until now we didn't know of a suitable material to study this in great depth." In the case of high-temperature superconductors, the linear relationship between temperature and resistance is usually only detectable in a relatively small temperature range, and, furthermore, various effects that inevitably occur at higher temperatures can influence this relationship in complicated ways.

Many experiments have already been carried out with an exotic material (YbRh2Si2) that displays strange metal behaviour over an extremely wide temperature range - but, surprisingly, no superconductivity seemed to emerge from this extreme "strange metal" state. "Theoretical considerations have already been put forward to justify why superconductivity is simply not possible here," says Silke Bühler-Paschen. "Nevertheless, we decided to take another look at this material."

Record-breaking temperatures

At TU Wien, a particularly powerful low-temperature laboratory is available. "There we can study materials under more extreme conditions than other research groups have been able to do so far," explains Silke Bühler-Paschen. First, the team was able to show that in YbRh2Si2 the linear relationship between resistance and temperature exists in an even larger temperature range than previously thought - and then they made the key discovery: at extremely low temperatures of only one millikelvin, the strange metal turns into a superconductor.

"This makes our material ideally suited for finding out in what way the strange metal behaviour leads to superconductivity," says Silke Bühler-Paschen.

Paradoxically, the very fact that the material only becomes superconducting at very low temperatures ensures that it can be used to study high-temperature superconductivity particularly well: "The mechanisms that lead to superconductivity are visible particularly well at these extremely low temperatures because they are not overlaid by other effects in this regime. In our material, this is the localisation of some of the conduction electrons at a quantum critical point. There are indications that a similar mechanism may also be responsible for the behaviour of high-temperature superconductors such as the famous cuprates," says Silke Bühler-Paschen.

Classical molecular sieve membranes, with 3D microparticles and 2D nanosheets as primary building blocks, are promising in chemical separation.

Separation within such membranes relies on molecular movement and transport though their intrinsic or artificial nanopores. Since the weak connections by nature between the neighboring "bricks" usually result in intercrystalline gaps in membranes, the prevailing selectivity for classical molecular sieve membranes is moderate.

Recently, a research group led by Prof. YANG Weishen and Dr. BAN Yujie from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) proposed zero-dimensional molecular sieve membranes that could enhance the separation selectivity of hydrogen (H2) and carbon dioxide (CO2).

The study was published in Angewandte Chemie International Edition on July 16.

"Zero-dimensional molecules, as primary building blocks in the proposed membrane, have the potential to absolutely eliminate intercrystalline gaps in membranes," said Dr. BAN.

The researchers fabricated the zero-dimensional molecular sieve membrane by orderly assembling zero-dimensional 2-methylimidazole (mim) molecules into unprecedented supramolecule array membranes (SAMs) through solvent-free vapor processing on a metal-organic framework.

In SAMs, the "zero-dimensional building blocks" together with supramolecule interactions resulted in the absence of the intercrystalline gaps, which guaranteed an effective mass-transfer through intermolecular spacings instead of an undesirable leakage through non-selective gaps.

In contrast to the classical transport though nanopores of membranes, selective transport through the intermolecular spacing of mim (~0.30 nm) was realized within SAMs, yielding an extremely precise sieving of H2 from CO2. The H2/CO2 selectivity was one order of magnitude higher than selectivities of the state-of-the-art classical membranes.

"Our study opens the door to create a variety of SAMs to distinguish the subtle size/shape differences of a pair of gas molecules," said Prof. YANG. "In the future, we will tailor the intermolecular spacing, control the assembly process, and enable a wide range of application of SAMs to energy-efficient chemical separation processes."

Professors at Ural Federal University (UrFU, Russia) Sergey Shcheklein and Aleksey Dubinin have developed a technology for generating energy for an electric car engine using methanol. An article describing the technology was published in the International Journal of Hydrogen Energy.

"We pour methanol into the fuel tank. An air converter, which processes methanol into a gas mixture, is installed directly inside the vehicle. A mixture or synthesis gas, consisting of hydrogen and carbon monoxide, is formed in a small volume, which is necessary for the current operation of an electric vehicle engine," said Sergey Shcheklein, head of the Department of Nuclear Power Plants and Renewable Energy Sources at UrFU.

The synthesis gas is fed to an electrochemical generator based on a solid oxide fuel cell (SOFC). Hydrogen is oxidized in the SOFC anode, the energy of this chemical reaction is converted into electrical energy. Carbon monoxide enters a separate combustion chamber, where it is oxidized by air with the release of thermal energy. Thermal energy is used to vaporize methanol and heat the catalyst involved in the conversion of methanol into a gas mixture. Emissions of residual carbon dioxide are insignificant.

Methanol is a non-explosive substance, the simplest alcohol, its production is not expensive: methanol can be obtained from any organic resources, including plant biomass and solid domestic waste. At the same time, the electrical efficiency of a power plant with SOFC is more than 42%, which corresponds to the level of the best promising internal combustion engines. For comparison: efficiency, i.e. the efficiency of converting the energy of liquid and gaseous fuels into mechanical energy, of diesel engines is 25%, for gasoline engines - about 20%.

Sergey Shcheklein and Aleksey Dubinin came up with the idea of using methanol after analyzing more than 220 experiments. Scientists have tried to obtain synthesis gas from various natural hydrocarbon fuels: coal, gas, oil products. Development using methanol turned out to be technologically simple, with minimal energy consumption and energy losses, and high efficiency.

"In other words, less fuel and oxidizer are required to produce a unit of energy compared to existing internal combustion engines. Consequently, less air is consumed from the atmosphere, significantly fewer combustion products, such as carbon dioxide and the life-threatening nitrogen dioxide, are formed," said Sergey Shcheklein.

Besides, methanol is suitable for one another task that UrFU scientists are solving - to use nuclear energy sources for the production of "raw materials" for SOFCs.

Conversion of hydrocarbon fuels into gas mixtures requires high temperatures, which modern light-water nuclear reactors cannot provide; their thermodynamic potential is almost half as much. At the same time, obtaining methanol from methane using modern nuclear reactors (such as fast neutron reactors) is not only possible but also the most energetically efficient way.

The methanol processing technology proposed by Sergey Shcheklein and Alexey Dubinin is also suitable for the energy and metallurgical industries. This work is part of the five-year project "Thermodynamic Analysis of Hydrogen Use for Metallurgical and Power Engineering Enterprises," which was carried out under a state assignment from the Ministry of Science and Higher Education of the Russian Federation.

Note

According to scientists, given the current level of oil and gas consumption, these sources of energy will be enough for mankind for the next 60 years. At the same time, the development of new deposits of fossil fuels leads to the degradation of production areas, including the Arctic, to the melting of permafrost and the release of colossal volumes of methane. This enhances the greenhouse effect and ozone depletion. The problem is the emissions of hydrocarbon fuel combustion products lead to environmental pollution.

One of the alternative methods of generating electricity is the use of solid oxide fuel cells. SOFCs are environmentally friendly devices with high, up to 70%, and higher efficiency, in which chemical energy is converted into electricity.

Solid oxide fuel cells function on hydrogen fuel. Hydrogen is the most abundant element, its reserves are inexhaustible, and it is environmentally friendly. The use of hydrogen in conjunction with electrochemical power generators opens up great prospects for the creation of electric transport, increasing the energy efficiency and environmental safety of vehicles of any scale. In this case, emissions of harmful substances either have zero values or are tens and hundreds of times less.

However, it is rather difficult to obtain pure hydrogen, since it easily enters into chemical reactions. In addition, hydrogen is characterized by high fluidity, large specific volume in the gaseous form, high potential explosion hazard, and requires complex technologies for storage and transportation. At the same time, the existing methods for producing hydrogen are energy-intensive and require large amounts of electrical energy. Its traditional source is power plants that run on coal, gas, and oil. Thus, the benefits of using hydrogen are significantly leveled, and a large-scale application of hydrogen technologies in transport is not yet possible. However, the prospects for producing hydrogen to obtain atomic and hydraulic energy, all types of renewable energy sources have the opportunity to eliminate these disadvantages and realize all the advantages of hydrogen fuel already in the 21st century.

Carbohydrates have traditionally been the largest source of energy intake for much of the world's population1. However, without a standard definition for carbohydrate quality, some foods that contain carbohydrates are often stigmatized based on isolated and reductionist assessment methods that fail to consider their contributions to nutrient intakes and balanced, healthy diets. A new perspective piece, published in Advances in Nutrition, brings to light the pressing need to define carbohydrate quality, to better assess the value of nutrient-dense carbohydrate-containing foods in healthy lifestyles. Ultimately, the authors call for a more holistic approach to carbohydrate guidance to address the complex needs of both people and the planet.

"To date, terms like 'good carbs' and 'bad carbs' have been inconsistently assigned to a plethora of foods based on overly simplistic and narrowly focused measures, like glycemic index (GI) or fiber content," states Rebekah Schulz of University of Minnesota and perspective piece coauthor. "While these aspects can be individual pieces of the puzzle, they don't reflect the full picture of carbohydrate quality. For example, while GI may be a useful index in isolation, it is not representative of real-life dietary intake when carbohydrates are consumed with other foods, nor does it account for a food's overall nutrient content or planetary impact."

This paper addresses the strengths and weaknesses of current methods used to assess carbohydrate quality, proposes additional indices to include in a standardized quality carbohydrate definition, and defines research questions for further exploration. Within the perspective piece, authors analyzed various existing frameworks for carbohydrate quality and weighed the pros and cons of indexing based solely on measures such as GI, whole grain foods, fiber and added sugar.

The authors concluded that, "for truly relevant and applicable dietary guidance, the framework should focus on nutrient contributions and take into account various ways to measure and analyze nutrients, as well as be nimble to adjust for new research findings and data."

Carbohydrate Quality: Spotlight on Fruits & Vegetables

The authors also note that current approaches to assessing carbohydrate quality may lead to even greater consumer confusion of nutritional recommendations for specific foods, including fruits and vegetables. Given that one in 10 Americans fall short of meeting their fruit and vegetable requirements2, it's important that a holistic and standardized approach to dietary carbohydrate guidance is established to promote both human and planetary health as effectively as possible.

"Potatoes are one example of a food that tends to be misclassified or misunderstood based significantly on their GI value - even though preparation techniques and common consumption methods are not reflected accurately within a GI value," points out Joanne Slavin, PhD, RD of University of Minnesota and perspective piece coauthor. "Potatoes are a nutrient-dense vegetable that provide several important nutrients - like fiber, potassium, Vitamin C and resistant starch - to Americans' diets and have been consumed for centuries as a main staple in various cultures. Additionally, potatoes serve an important role in food security in developing countries."

A Forward-Looking Solution: Establishing a Standardized Carbohydrate Quality Metric

Overall, there is a general shift away from one-directional and overly simplified dietary guidance, as any food or nutrient can have a place as part of a healthy lifestyle. Thus, to best define high quality carbohydrates, the authors call for a standardized carbohydrate quality metric, such as an algorithm that encompasses a broader spectrum of factors.

"There is a need to provide easy tools grounded in strong science," added Schulz. "When consumers need to make a quick choice about carbohydrate-containing foods, they should feel comfortable knowing that there is a comprehensive, science-backed formula or algorithm behind-the-scenes helping guide this decision."

The authors propose several potential quality indices to be considered when assessing carbohydrate quality:

Whole-grain, fiber, and added-sugar content

Ratios of total carbohydrate to fiber and added sugar to fiber in a food

Protein quality

Degree of processing

Environmental impact of a food

"As dietary guidance rightly moves away from isolated nutrient recommendations toward broader and more flexible dietary patterns, it's clear we need to better define the quality underpinnings of these patterns, including carbohydrates," notes Slavin. "By establishing an algorithm to assess carbohydrate quality, the result would positively impact both health and environmental outcomes and create consistent ways to measure intake across populations."

Each year, hundreds of thousands of people worldwide suffer from peripheral nerve injuries, which often leave them with long-term disabilities. The peripheral nervous system is analogous to the circulatory system; a network of vessels that reaches all parts of the body, but instead of blood flowing through vessels, electrical signals propagate information through thin fibers called axons, which are engulfed within nerve trunks. These nerve trunks are the communication network relaying information from all parts of the body to the brain, coordinating activity, and generating motor and sensory function. If one of the nerve trunks is damaged or torn - a common condition in limb injuries - a patient can experience pain, paralysis and even a life-long disability.

In such situations, surgical intervention is necessary to repair the damaged nerve. The standard treatments are direct suturing of detached nerves or, in cases where the gap formed in the nerve trunk is large, surgeons transfer an intact nerve trunk from the patient's leg and implant it at the site of the injury, thus creating damage in another area (i.e., the leg). Today, there are methods to rejoin nerve trunks to allow the axons to regrow and restore motor and sensory function. One such method is by implanting a synthetic hollow nerve conduit aimed at bridging the gap and allowing the nerve to heal without secondary damage to the patient.

One of the main problems preventing optimal regeneration is that axons within severed nerves have difficulty regenerating and reaching their target. This may be attributed in part to misguided axons that sprout in multiple directions, decreasing probability to reach their target organs. "They need orienting cues to help them," explains Prof. Orit Shefi, of Bar-Ilan University's Kofkin Faculty of Engineering, Institute for Nanotechnology and Advanced Materials, and Gonda (Goldschmied) Multidisciplinary Brain Research Center. Dr. Merav Antman-Passig, a researcher in her lab, adds: "These guiding instructions need to remain in the body for an extended time, since axons grow fairly slowly."

A technique developed by the research team of Prof. Shefi's laboratory, led by Dr. Antman-Passig and Dr. Jonathan Giron, is used to fill a nerve conduit with gel containing a number of physical and chemical components that promote and align axon regrowth. Their technique was recently published in Advanced Functional Materials.

The researchers filled hollow nerve conduits with engineered aligned collagen gels. In the body, aligned collagen fibers help axon pathfinding, but, in the hollow nerve guides available today, the aligned collagen fibers are absent. The aligned collagen gel acts as a scaffold for axons and directs their growth. In addition, the conduits contain a substance called NGF (nerve growth factor) which, as its name implies, is essential for the growth of the nervous system. "Imagine that we implanted guiding cues in the gel, which are the aligned collagen fibers, and that these guiding cues also have a treat for the growing axons," explains Dr. Antman-Passig "like bait neatly scattered for the growing axons." Prof. Shefi adds: "An axon that reaches the gel follows these cues and finds the right direction more easily. In fact, the novel system combines several techniques for nerve regeneration. Axons like to grow toward these markers that can be left for them, like collagen scaffolding and NGF. The novelty of our method is in the engineering of an organized tissue-like gel that contains components that help restore the nerves, and especially in extending the duration of activity of the gel in the body. If collagen and NGF are simply added in hollow nerve conduits, just like real bait, different cells consume them and actually break them down. After a short time, the growing axons do not have these road signs. In the method we developed, we extended the time that these factors are accessible to axons during regeneration. We did this by incorporating NGF-coated magnetic particles that we arranged into the correct structure via a magnetic alignment strategy. This also creates an arrangement of the particles and collagen."

After characterizing the gel components, the researchers implanted them in nerve conduits and examined the direction of their growth and the platform's efficacy. The researchers measured the direction of the cell growth and found that with the help of the gel combining aligned collagen and NGF- coated particles, they were able to direct and enhance their growth. Subsequently, they examined the efficacy of the conduit in the rehabilitation of rats with peripheral nerve injury at the sciatic nerve, which prevented them from walking properly. The number of axons that penetrated the innovative gel-filled tube and successfully crossed the injured area was greater compared to the empty tube, and accordingly the restoration of nerve tissue was the highest. The researchers showed that with the implantation of the tubes and the use of the engineered collagen gel, the functional motor restoration was highest, in comparison to the use of other types of conduits and compared to conduits with gel that was not enriched.

The researchers are now exploring commercialization options and hope that will help functional recovery and accelerate nerve repair following injury.

A far-reaching new study of the life-cycle greenhouse gas (GHG) emissions from passenger cars, including SUVs, draws sharp and meticulous distinctions between the climate impacts of battery and fuel cell electric vehicles on one hand and combustion vehicles on the other.

The detailed findings can be summarized straightforwardly. Only battery electric vehicles (BEVs) and fuel cell electric vehicles (FCEVs) powered by renewable electricity can achieve the kind of deep reductions in GHG emissions from transportation that comport with the Paris Agreement's goal of keeping global warming well below 2 °C. There is no realistic pathway to that goal that relies on combustion-engine vehicles, including hybrids of any sort.

The study, carried out by the International Council on Clean Transportation (ICCT), analyzes present and projected future GHG emissions attributable to every stage in the life cycles of both vehicles and fuels, from extracting and processing raw materials through refining and manufacture to operation and eventual disposal. The analysis was performed separately and in depth for the European Union, the United States, China, and India, and captured the differences among those markets, which together account for about 70% of new car sales worldwide.

"One important result of the analysis is to show that life-cycle emissions trends are similar in all four regions, despite the differences among them in vehicle mix, grid mix, and so on. Already for cars registered today, BEVs have better relative GHG emissions performance everywhere than conventional vehicles," said ICCT Deputy Director Rachel Muncrief.

In addition to its global scope, the study is methodologically comprehensive in considering all relevant powertrain types, including plug-in hybrid electric vehicles, and an array of fuel types including biofuels, electrofuels, hydrogen, and electricity. The life-cycle GHG emissions of cars registered in 2021 are compared with those of cars expected to be registered in 2030.

"Our aim with this study was to capture the elements that policymakers in these major markets need to fairly and critically evaluate different technology pathways for passenger cars," said ICCT researcher Georg Bieker, the study's author. "We know we need transformational change to avoid the worst impacts of climate change, and the results show that certain technologies are going to be capable of delivering deep decarbonization and others are clearly not."

The study methodology is innovative and distinguished from other life-cycle analyses' in additional important ways. It considers lifetime average carbon intensity of fuel and electricity mixes, and accounts for changes in the carbon intensity over vehicle lifetime given present energy policies. It also looks at real-world usage rather than relying on official test values to estimate fuel and electricity consumption; this is especially important in assessing GHG emissions of plug-in hybrid electric vehicles (PHEVs). It uses the most recent data on industrial-scale battery production and considers regional supply chains, which results in significantly lower estimates of GHG emissions from battery production than other studies have found. And it factors in the near-term global warming potential of methane leakage in natural gas and natural gas-derived hydrogen pathways.

"Even for India and China, which are still heavily reliant on coal power, the life-cycle benefits of BEVs are present today," said Peter Mock, ICCT's managing director for Europe. Pointing to the importance of the findings to the European Union's recently proposed changes to its passenger car CO2 emission regulation, he added, "The results highlight the importance of grid decarbonization alongside vehicle electrification. The life-cycle GHG performance of electric cars will improve as grids decarbonize, and regulations that promote electrification are crucial to capturing the future benefits of renewable energy."

A new wearable brain-machine interface (BMI) system could improve the quality of life for people with motor dysfunction or paralysis, even those struggling with locked-in syndrome - when a person is fully conscious but unable to move or communicate.

A multi-institutional, international team of researchers led by the lab of Woon-Hong Yeo at the Georgia Institute of Technology combined wireless soft scalp electronics and virtual reality in a BMI system that allows the user to imagine an action and wirelessly control a wheelchair or robotic arm.

The team, which included researchers from the University of Kent (United Kingdom) and Yonsei University (Republic of Korea), describes the new motor imagery-based BMI system this month in the journal Advanced Science.

"The major advantage of this system to the user, compared to what currently exists, is that it is soft and comfortable to wear, and doesn't have any wires," said Yeo, associate professor on the George W. Woodruff School of Mechanical Engineering.

BMI systems are a rehabilitation technology that analyzes a person's brain signals and translates that neural activity into commands, turning intentions into actions. The most common non-invasive method for acquiring those signals is ElectroEncephaloGraphy, EEG, which typically requires a cumbersome electrode skull cap and a tangled web of wires.

These devices generally rely heavily on gels and pastes to help maintain skin contact, require extensive set-up times, are generally inconvenient and uncomfortable to use. The devices also often suffer from poor signal acquisition due to material degradation or motion artifacts - the ancillary "noise" which may be caused by something like teeth grinding or eye blinking. This noise shows up in brain-data and must be filtered out.

The portable EEG system Yeo designed, integrating imperceptible microneedle electrodes with soft wireless circuits, offers improved signal acquisition. Accurately measuring those brain signals is critical to determining what actions a user wants to perform, so the team integrated a powerful machine learning algorithm and virtual reality component to address that challenge.

The new system was tested with four human subjects, but hasn't been studied with disabled individuals yet.

"This is just a first demonstration, but we're thrilled with what we have seen," noted Yeo, Director of Georgia Tech's Center for Human-Centric Interfaces and Engineering under the Institute for Electronics and Nanotechnology, and a member of the Petit Institute for Bioengineering and Bioscience.

New Paradigm

Yeo's team originally introduced soft, wearable EEG brain-machine interface in a 2019 study published in the Nature Machine Intelligence. The lead author of that work, Musa Mahmood, was also the lead author of the team's new research paper.

"This new brain-machine interface uses an entirely different paradigm, involving imagined motor actions, such as grasping with either hand, which frees the subject from having to look at too much stimuli," said Mahmood, a Ph. D. student in Yeo's lab.

In the 2021 study, users demonstrated accurate control of virtual reality exercises using their thoughts - their motor imagery. The visual cues enhance the process for both the user and the researchers gathering information.

"The virtual prompts have proven to be very helpful," Yeo said. "They speed up and improve user engagement and accuracy. And we were able to record continuous, high-quality motor imagery activity."

According to Mahmood, future work on the system will focus on optimizing electrode placement and more advanced integration of stimulus-based EEG, using what they've learned from the last two studies.

Activism and the Clinical Ethicist

Christopher Meyers

Although clinical ethics scholarship and practice have largely avoided assuming an activist stance, the many health care crises of the last 18 months motivated a distinct change: activist language has permeated conversations over such issues as the impact of triage policies on persons with disabilities and of color, and how the health care system has historically failed African Americans. "This activism is, to my mind, an overdue and welcome turn, and my goal here is to defend it--generally and with particular emphasis on institutional activism," writes Meyers, a professor emeritus of philosophy and a director emeritus of the Kegley Institute of Ethics at California State University, Bakersfield.

Other Voices:

Activism and Bioethics: Taking a Stand on Things That Matter

Wendy A. Rogers and Jackie Leach Scully take a broader view than Meyers, looking beyond activism within individual institutions and arguing that some issues are so morally egregious that bioethicists have a duty to take a stand against them, even if the prospects of success are dim.

Antiracism Activism in Clinical Ethics: What's Stopping Us?

Holly Vo and Georgina D. Campelia write that clinical ethicists should recognize barriers imbedded in the field of clinical ethics itself and support antiracism work by altering their institutional structures to be more inclusive.

Why Clinical Ethicists Are Not Activists

Carl Elliott notes that activism is rare among clinical ethicists because they have little formal power and few job protections. "Asking the clinical ethicist to fix the problems of an academic health center is like asking the butler to fix the problems of the British monarchy. He is not there to rule, but to serve."

New Rochelle, NY, July 21, 2021-- Evaluating the efficacy of novel therapies requires the ability to monitor wound progression accurately and reproducibly over time. Researchers have proposed a new scoring system for wound healing in mice based on parameters in each phase of healing, as described in an article in the peer-reviewed journal Stem Cells and Development. Click here to read the article for free through August 21, 2021.

The parameters include re-epithelization, epithelial thickness index, keratinization, granulation tissue thickness, remodeling, and the scar elevation index. The parameters can be assessed using either Hematoxylin & Eosin or Masson's Trichrome staining. Mari van de Vyver, from Stellenbosch University, and colleagues developed this histology scoring system for murine cutaneous wounds. They then validated the system in four different types of murine skin wound models.

"This histological scoring system defines and describes the minimum recommended criteria for assessing wound healing dynamics," state the authors. "The experience and ability of investigators to accurately identify structures in histology slides at different stages of healing is crucial for consistency and repeatability of measures to deliver meaningful results."

"The development and validation of this scoring system in a randomized blinded investigation by researchers from Stellenbosch University (South Africa), Polish Academy of Sciences in Olsztyn (Poland), University of Texas Southwestern Medical Center (Texas, USA) and Obatala Sciences Inc. (New Orleans, USA) represents a truly international effort to advance the robust and accurate assessment of wound healing," states Graham C. Parker, PhD, Editor-in-Chief of Stem Cells and Development and The Carman and Ann Adams Department of Pediatrics, Wayne State University School of Medicine, Detroit, MI.