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    Novel assay finds new mechanism underlying red blood cell aging

    Red blood cells are the most abundant cell type in blood, carrying oxygen throughout the human body. In blood circulation, they repetitively encounter various levels of oxygen tension. Hypoxia, a low oxygen tension condition, is a very common micro-environmental factor in physiological processes of blood circulation and various pathological processes such as cancer, chronic inflammation, heart attacks and stroke. In addition, an interplay between poor cellular deformability and impaired oxygen delivery is found in various pathological processes such as sickle cell disease. Sickle red blood cells simultaneously undergo drastic mechanical deformation during the sickling and unsickling process.
    The interactions between hypoxia and cell biomechanics and the underlying biochemical mechanisms of the accelerated damage in diseased red blood cells are well understood, however, the exact biomechanical consequences of hypoxia contributing to red blood cell degradation (aging) remains elusive.
    Researchers from Florida Atlantic University’s College of Engineering and Computer Science, in collaboration with the Massachusetts Institute of Technology (MIT), sought to identify the role of hypoxia on red blood cell aging via the biomechanical pathways. In particular, they examined hypoxia-induced impairment of red blood cell deformability at the single cell level, compared the differences between non-cyclic hypoxia and cyclic hypoxia, and documented any cumulative effect vs. hypoxia cycles, such as aspects that have not been studied quantitatively. Red blood cell deformability is an important biomarker of its functionality.
    For the study, published in the journal Lab on a Chip, researchers developed a multifaceted microfluidic in vitro assay to precisely control the gaseous environment while probing the mechanical performance of red blood cells, which can be used as a characterization tool for other cell types involved in oxygen-dependent biological processes. The assay holds promise for investigating hypoxic effects on the metastatic potential and relevant drug resistance of cancer cells. Cancer cells are more metastatic in a hypoxic tumor microenvironment and cancer cell stiffness has been shown to be an effective biomarker of their metastatic potential.
    Findings from the study indicate an important biophysical mechanism underlying red blood cell aging in which the cyclic hypoxia challenge alone can lead to mechanical degradation of the red blood cell membrane. This process in combination with the deformation-induced mechanical fatigue represents two major fatigue loading conditions that circulating red blood cells experience.
    “A unique feature of our system lies in that the cell deformability measurement can be made on multiple, individually tracked red blood cells under a well-controlled oxygen tension environment,” said Sarah Du, Ph.D., senior author, an associate professor in FAU’s Department of Ocean and Mechanical Engineering, and a member of FAU’s Institute for Human Health and Disease Intervention (I-HEALTH). “Our results showed that the deformability of red blood cells decreases under deoxygenation conditions by before-and-after mechanical characterization of individual cells in response to the switching of oxygen levels within a microfluidic device.”
    Microfluidics serves as a miniaturized and efficient platform for gas diffusion by interfacing the gas and aqueous solution through flow or a gas-permeable membrane, which also is amenable to the control of the cellular gaseous microenvironment.
    For the study, researchers subjected red blood cells to a well-controlled repeated hypoxia microenvironment while allowing simultaneous characterization of the cell mechanical properties. They integrated an electro-deformation technique into a microdiffusion chamber, which was easy to implement and flexible in simultaneous applications of cyclic hypoxia challenge and shear stresses on individual cells in suspension and under quasi-stationary conditions.
    Measurements of biomarkers, such as oxidative damage, can provide additional information to establish quantitative relationships between the fatigue loading and the biological processes, allowing a better understanding of red blood cell failure and aging. The microfluidic assay also can be extended to study other types of biological cells for their mechanical performance and response to gaseous environments.
    “The unique method developed by professor Du’s lab also can be a useful tool to predict the mechanical performance of natural and artificial red blood cells for transfusion purposes as well as to assess the efficacy of relevant reagents in extending the cellular lifespan in circulation,” said Stella Batalama, Ph.D., dean, College of Engineering and Computer Science. “This promising and cutting-edge assay has the potential to further extend to red blood cells in other blood diseases and other cell types.”
    Study co-authors are Ming Dao, Ph.D., Department of Materials Science and Engineering, MIT; Yuhao Qiang, Ph.D., FAU College of Engineering and Computer Science and currently a postdoctoral researcher at MIT; and Jia Liu, Ph.D., FAU College of Engineering and Computer Science.
    This research is based on the materials supported by the National Science Foundation.
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    Materials provided by Florida Atlantic University. Original written by Gisele Galoustian. Note: Content may be edited for style and length. More

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    A new way to solve the ‘hardest of the hard’ computer problems

    A relatively new type of computing that mimics the way the human brain works was already transforming how scientists could tackle some of the most difficult information processing problems.
    Now, researchers have found a way to make what is called reservoir computing work between 33 and a million times faster, with significantly fewer computing resources and less data input needed.
    In fact, in one test of this next-generation reservoir computing, researchers solved a complex computing problem in less than a second on a desktop computer.
    Using the now current state-of-the-art technology, the same problem requires a supercomputer to solve and still takes much longer, said Daniel Gauthier, lead author of the study and professor of physics at The Ohio State University.
    “We can perform very complex information processing tasks in a fraction of the time using much less computer resources compared to what reservoir computing can currently do,” Gauthier said.
    “And reservoir computing was already a significant improvement on what was previously possible.”
    The study was published today (Sept. 21, 2021) in the journal Nature Communications. More

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    New AI tool accelerates discovery of truly new materials

    Researchers at the University of Liverpool have created a collaborative artificial intelligence tool that reduces the time and effort required to discover truly new materials.
    Reported in the journal Nature Communications, the new tool has already led to the discovery of four new materials including a new family of solid state materials that conduct lithium. Such solid electrolytes will be key to the development of solid state batteries offering longer range and increased safety for electric vehicles. Further promising materials are in development.
    The tool brings together artificial intelligence with human knowledge to prioritise those parts of unexplored chemical space where new functional materials are most likely to be found.
    Discovering new functional materials is a high-risk, complex and often long journey as there is an infinite space of possible materials accessible by combining all of the elements in the periodic table, and it is not known where new materials exist.
    The new AI tool was developed by a team of researchers from the University of Liverpool’s Department of Chemistry and Materials Innovation Factory, led by Professor Matt Rosseinsky, to address this challenge.
    The tool examines the relationships between known materials at a scale unachievable by humans. These relationships are used to identify and numerically rank combinations of elements that are likely to form new materials. The rankings are used by scientists to guide exploration of the large unknown chemical space in a targeted way, making experimental investigation far more efficient. Those scientists make the final decisions, informed by the different perspective offered by the AI.
    Lead author of the paper Professor Matt Rosseinsky said: “To date, a common and powerful approach has been to design new materials by close analogy with existing ones, but this often leads to materials that are similar to ones we already have.
    “We therefore need new tools that reduce the time and effort required to discover truly new materials, such as the one developed here that combines artificial intelligence and human intelligence to get the best of both.
    “This collaborative approach combines the ability of computers to look at the relationships between several hundred thousand known materials, a scale unattainable for humans, and the expert knowledge and critical thinking of human researchers that leads to creative advances.
    “This tool is an example of one of many collaborative artificial intelligence approaches likely to benefit scientists in the future.”
    Society’s capacity to solve global challenges such as energy and sustainability is constrained by our capability to design and make materials with targeted functions, such as better solar absorbers making better solar panels or superior battery materials making longer range electric cars, or replacing existing materials by using less toxic or scarce elements.
    These new materials create societal benefit by driving new technologies to tackle global challenges, and they also reveal new scientific phenomena and understanding. All modern portable electronics are enabled by the materials in lithium ion batteries, which were developed in the 1980s, which emphasises how just one materials class can transform how we live: defining accelerated routes to new materials will open currently unimaginable technological possibilities for our future.
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    Materials provided by University of Liverpool. Note: Content may be edited for style and length. More

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    One of nature’s key constants is much larger in a quantum material

    A crucial number that rules the universe goes big in a strange quantum material.

    The fine-structure constant is about 10 times its normal value in a type of material called quantum spin ice, physicists calculate in the Sept. 10 Physical Review Letters. The new calculation hints that quantum spin ice could give a glimpse at physics within an alternate universe where the constant is much larger.

    With an influence that permeates physics and chemistry, the fine-structure constant sets the strength of interactions between electrically charged particles. Its value, about 1/137, consternates physicists because they can’t explain why it has that value, even though it is necessary for the complex chemistry that is the basis of life (SN: 11/2/16).

    If the fine-structure constant throughout the cosmos were as large as the one in quantum spin ices, “the periodic table would only have 10 elements,” says theoretical physicist Christopher Laumann of Boston University. “And it probably would be hard to make people; there wouldn’t be enough richness to chemistry.”

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    Quantum spin ices are a class of substances in which particles can’t agree. The materials are made up of particles with spin, a quantum version of angular momentum, which makes them magnetic. In a normal material, particles would come to a consensus below a certain temperature, with the magnetic poles lining up in either the same direction or in alternating directions. But in quantum spin ices, the particles are arranged in such a way that the magnetic poles, or equivalently the spins, can’t agree even at a temperature of absolute zero (SN: 2/13/11).

    The impasse occurs because of the materials’ geometry: The particles are located at the corners of an array of pyramids that are connected at the corners. Conflicts between multiple sets of neighbors mean that the closest these particles can get to harmony is arranging themselves so that two spins face out from each pyramid, and two face in.

    In quantum spin ices, particles (black dots) are located at the corners of an array of pyramids (red). Normally, the spins of the particles (green arrows) arrange so that two are pointing into the pyramid and two out. If that rule is broken, as illustrated, quasiparticles called spinons (orange and blue) form.S.D. Pace et al/PRL 2021

    This uneasy truce can give rise to disturbances that behave like particles within the material, or quasiparticles (SN: 10/3/14). Flip particles’ spins around and you can get what are called spinons, quasiparticles that can move through the material and interact with other spinons in a manner akin to electrons and other charged particles found in the world outside the material. The material re-creates the theory of quantum electrodynamics, the piece of particles physics’ standard model that hashes out how electrically charged particles do their thing. But the specifics, including the fine-structure constant, don’t necessarily match those in the wider universe.

    So Laumann and colleagues set out to calculate the fine-structure constant in quantum spin ices for the first time. The team pegged the number at about 1/10, instead of 1/137. What’s more, the researchers found that they could change the value of the fine-structure constant by tweaking the properties of the theoretical material. That could help scientists study the effects of altering the fine-structure constant — a test that’s well out of reach in our own universe, where the fine-structure constant is fixed.

    Unfortunately, scientists haven’t yet found a material that definitively qualifies as quantum spin ice. But one much-studied prospect is a group of minerals called pyrochlores, which have magnetic ions, or electrically charged atoms, arranged in the appropriate pyramid configuration. Scientists might also be able to study the materials using a quantum computer or another quantum device designed to simulate quantum spin ices (SN: 6/29/17).

    If scientists succeed in creating quantum spin ice, the materials could reveal how quantum electrodynamics and the standard model would work in a universe with a much larger fine-structure constant. “That would be the hope,” says condensed matter theorist Shivaji Sondhi of the University of Oxford, who was not involved with the research. “It’s interesting to be able to make a fake standard model … and ask what would happen.” More

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    Students’ certainty about belonging and their performance in a STEM course reinforce each other – for better or worse

    As a first-year college student in an introductory chemistry class sits down for their midterm, which might be their first stepping stone toward a career in academia, research or medicine, a thought may swirl through their head alongside valence numbers, molar masses and oxidation states — an anxiety that forms itself into a supposition: “Maybe people like me don’t belong in this class.”
    That thought is called belonging uncertainty, a feeling of social insecurity related to a person’s identity. New research from the University of Utah shows that belonging insecurity in a STEM course, specifically a first-year chemistry course, can affect a student’s midterm scores, which can then feed back into the student’s belonging uncertainty. For students in groups that are underrepresented in STEM, there’s a danger that such a feedback loop could cause them to decide that science isn’t for them, deterring potential scientists from even entering a STEM field.
    “Students in these early STEM courses face many struggles and challenges, such as learning to adjust their study strategies, that are normal for this academic transitional period from high school to college,” says chemistry professor Gina Frey. “The concern is that a student with a high belonging uncertainty has a less stable sense of belonging and will believe the struggles they encounter in these courses are due to their identities as opposed to a normal part of the academic transition that everyone faces in their early years at college.”
    The research is published in the Journal of Chemical Education in a special issue on diversity, equity, inclusion and respect in chemistry education research and practice.
    Sense of belonging and belonging uncertainty
    Belonging uncertainty is different than simply a sense of belonging. A sense of belonging is an individual feeling, Frey says, (i.e. “Do I belong here?”) while belonging uncertainty is tied to the groups in which a person identifies. More

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    New computational platform to study biological processes

    Scientists have launched a unique software that is able to perform highly complex simulations of a variety of biological processes.
    Agent-based simulations (ABS) are powerful computational tools that help scientists understand complex biological systems. These simulations are an inexpensive and efficient way to quickly test hypotheses about the physiology of cellular tissues, organs, or entire organisms. However, many ABS do not take full advantage of available computational power, and the majority of ABS platforms on the market are designed with a particular use case in mind.
    In a paper published by Bioinformatics, a consortium that includes the University of Surrey, CERN, Newcastle University, GSI Helmholtz Centre, University of Cyprus, University of Geneva, SCImPULSE Foundation and Immunobrain Checkpoint, unveil their open-source, multi-disciplinary simulation platform called BioDynaMo.
    In the paper, the consortium details how BioDynaMo can simulate complex medical cases in neuroscience, oncology, and epidemiology, thanks to its ability to utilise multi-core CPUs and offload computations to hardware accelerators.
    The team’s results show that BioDynaMo performs up to 945 times faster than current state-of-the-art baselines. The advances make it feasible to simulate each use case with one billion cells on a single server, showcasing the potential BioDynaMo has for computational biology research.
    Dr Roman Bauer from the University of Surrey, co-founder of the BioDynaMo initiative and senior author of the study, said:
    “I believe that if we are ever to tackle highly complex health issues such as Alzheimer, computer simulation tools like BioDynaMo will be critical for scientists moving forward.
    “In this paper, we have shown that BioDynaMO’s excellent features and performance. It will help the scientists of tomorrow pitting hypotheses against each other to study their subtle or less so divergences. And more importantly, it will help biomedical research become a truly interdisciplinary field of the 21st century.”
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    Materials provided by University of Surrey. Note: Content may be edited for style and length. More

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    Using internet in retirement boosts cognitive function

    Using the internet during your retirement years can boost your cognitive function, a new study has found.
    Researchers from Lancaster University Management School, the Norwegian University Science and Technology and Trinity College Dublin examined the cognitive function of more than 2,000 retired people from across Europe, and found that post-retirement internet usage is associated with substantially higher scores on tests.
    The study, published in the Journal of Economic Behavior and Organization, uses data drawn from the Survey of Health, Ageing and Retirement in Europe (SHARE) that collects information about the health, employment history and socio-economic status of older people.
    Focusing on a sample of 2,105 older people from Austria, Belgium, Denmark, France, Germany, Italy, Israel, Spain, Sweden and Switzerland who have been retired since 2004, researchers examined retirees’ cognitive function in both 2013 and 2015. They specifically focused on a word recall test, where individuals were asked to recall a list of 10 words immediately, and then again five minutes later.
    Results found that, on average, people who used the internet after they retired were able to recall 1.22 extra words in the recall test compared to non-internet users. However, retirees who used the internet were also more likely to be male, younger, better educated, and have been retired for a shorter period. They also appear to be in better health — even though they drink and smoke more.
    Dr Vincent O’Sullivan, a co-author from Lancaster University Management School said: “Our results reveal that using the internet, post-retirement, leads to a marked reduction in the rate of cognitive decline. More

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    Augmented reality helps tackle fear of spiders

    Researchers from the University of Basel have developed an augmented reality app for smartphones in order to help people reduce their fear of spiders. The app has already shown itself to be effective in a clinical trial, with subjects experiencing less fear of real spiders after completing just a few training units with the app at home.
    Fear of spiders is one of the most common phobias and leads to a variety of limitations in everyday life, as those affected seek to avoid situations involving spiders. For example, sufferers are known to avoid social occasions outdoors, visits to the zoo or certain travel destinations — or to excessively check rooms for spiders or avoid certain rooms, such as basements or lofts, altogether. One effective treatment for a fear of spiders is “exposure therapy,” in which patients are guided through therapeutic exposure to the situations they fear in order to gradually break down their phobia. This treatment is rarely used, however, because those affected are reluctant to expose themselves to real spiders.
    To remedy this situation, the interdisciplinary research team led by Professor Dominique de Quervain has developed a smartphone-based augmented reality app called Phobys. Writing in the Journal of Anxiety Disorders, the researchers have reported promising results with this app designed to tackle the fear of spiders.
    Phobys is based on exposure therapy and uses a realistic 3D spider model that is projected into the real world. “It’s easier for people with a fear of spiders to face a virtual spider than a real one,” explains Anja Zimmer, lead author of the study.
    Effectiveness verified in a study
    Zimmer and her colleagues analyzed the effectiveness of Phobys in a clinical trial involving 66 subjects. Over the course of two weeks, the participants — who all suffered from a fear of spiders — either completed six half-hour training units with Phobys or, in the case of the control group, were offered no intervention. Before and after treatment, the subjects approached a real spider in a transparent box as closely as their fear of spiders allowed. The group that had trained using Phobys showed significantly less fear and disgust in the real-life spider situation and was able to get closer to the spider than the control group.
    The Phobys app offers nine different levels so that subjects can get closer to — and even interact with — the virtual spider. With each level, the tasks become more intensive and therefore more difficult. Each level ends with an assessment of one’s own fear and disgust, and the app decides whether the level should be repeated or the user can move on to the next one. The app also makes use of game elements, such as rewarding feedback, animation and sound effects, to maintain a high level of motivation.
    Phobys is available in app stores
    Following refinement with the help of GeneGuide AG (specifically, the MindGuide Division), a spin-off from the University of Basel, the app is now available in the app stores for iPhones and Android smartphones. People suffering from mild forms of a fear of spiders can use the app on their own. In the case of people who suffer from a serious fear of spiders, the researchers recommend that the app only be used with the supervision of a professional. The app allows users to test whether they are afraid of a virtual spider for free, while the training to reduce their fear of spiders can be purchased in the app.
    The current study is one of several projects in progress at the Transfaculty Research Platform for Molecular and Cognitive Neurosciences, led by Professor Andreas Papassotiropoulos and Professor Dominique de Quervain, with the aim of improving the treatment of mental disorders through the use of new technologies and making these treatments widely available.
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    Materials provided by University of Basel. Note: Content may be edited for style and length. More