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News Article | May 23, 2017
Site: www.eurekalert.org

AMHERST, Mass. - A lightweight, comfortable jacket that can generate the power to light up a jogger at night may sound futuristic, but materials scientist Trisha Andrew at the University of Massachusetts Amherst could make one today. In a new paper this month, she and colleagues outline how they have invented a way to apply breathable, pliable, metal-free electrodes to fabric and off-the-shelf clothing so it feels good to the touch and also transports enough electricity to power small electronics. She says, "Our lab works on textile electronics. We aim to build up the materials science so you can give us any garment you want, any fabric, any weave type, and turn it into a conductor. Such conducting textiles can then be built up into sophisticated electronics. One such application is to harvest body motion energy and convert it into electricity in such a way that every time you move, it generates power." Powering advanced fabrics that can monitor health data remotely are important to the military and increasingly valued by the health care industry, she notes. Generating small electric currents through relative movement of layers is called triboelectric charging, explains Andrew, who trained as a polymer chemist and electrical engineer. Materials can become electrically charged as they create friction by moving against a different material, like rubbing a comb on a sweater. "By sandwiching layers of differently materials between two conducting electrodes, a few microwatts of power can be generated when we move," she adds. In the current early online edition of Advanced Functional Materials, she and postdoctoral researcher Lu Shuai Zhang in her lab describe the vapor deposition method they use to coat fabrics with a conducting polymer, poly(3,4-ethylenedioxytiophene) also known as PEDOT, to make plain-woven, conducting fabrics that are resistant to stretching and wear and remain stable after washing and ironing. The thickest coating they put down is about 500 nanometers, or about 1/10 the diameter of a human hair, which retains a fabric's hand feel. The authors report results of testing electrical conductivity, fabric stability, chemical and mechanical stability of PEDOT films and textile parameter effects on conductivity for 14 fabrics, including five cottons with different weaves, linen and silk from a craft store. "Our article describes the materials science needed to make these robust conductors," Andrew says. "We show them to be stable to washing, rubbing, human sweat and a lot of wear and tear." PEDOT coating did not change the feel of any fabric as determined by touch with bare hands before and after coating. Coating did not increase fabric weight by more than 2 percent. The work was supported by the Air Force Office of Scientific Research. Until recently, she and Zhang point out, textile scientists have tended not to use vapor deposition because of technical difficulties and high cost of scaling up from the laboratory. But over the last 10 years, industries such as carpet manufacturers and mechanical component makers have shown that the technology can be scaled up and remain cost-effective. The researchers say their invention also overcomes the obstacle of power-generating electronics mounted on plastic or cladded, veneer-like fibers that make garments heavier and/or less flexible than off-the-shelf clothing "no matter how thin or flexible these device arrays are." "There is strong motivation to use something that is already familiar, such as cotton/silk thread, fabrics and clothes, and imperceptibly adapting it to a new technological application." Andrew adds, "This is a huge leap for consumer products, if you don't have to convince people to wear something different than what they are already wearing." Test results were sometimes a surprise, Andrew notes. "You'd be amazed how much stress your clothes go through until you try to make a coating that will survive a shirt being pulled over the head. The stress can be huge, up to a thousand newtons of force. For comparison, one footstep is equal to about 10 newtons, so it's yanking hard. If your coating is not stable, a single pull like that will flake it all off. That's why we had to show that we could bend it, rub it and torture it. That is a very powerful requirement to move forward." Andrew is director of wearable electronics at the Center for Personalized Health Monitoring in UMass Amherst's Institute of Applied Life Sciences (IALS). Since the basic work reported this month was completed, her lab has also made a wearable heart rate monitor with an off-the-shelf fitness bra to which they added eight monitoring electrodes. They will soon test it with volunteers on a treadmill at the IALS human movement facility. She explains that a hospital heart rate monitor has 12 electrodes, while the wrist-worn fitness devices popular today have one, which makes them prone to false positives. They will be testing a bra with eight electrodes, alone and worn with leggings that add four more, against a control to see if sensors can match the accuracy and sensitivity of what a hospital can do. As the authors note in their paper, flexible, body-worn electronics represent a frontier of human interface devices that make advanced physiological and performance monitoring possible. For the future, Andrew says, "We're working on taking any garment you give us and turning it into a solar cell so that as you are walking around the sunlight that hits your clothes can be stored in a battery or be plugged in to power a small electronic device." Zhang and Andrew believe their vapor coating is able to stick to fabrics by a process called surface grafting, which takes advantage of free bonds dangling on the surface chemically bonding to one end of the polymer coating, but they have yet to investigate this fully.


News Article | April 26, 2017
Site: phys.org

"Frogs of the World" represents the first-ever use of 3D technology to preserve accurate, high-resolution models of some of the most endangered frog species on the planet, say Irschick and members of the interdisciplinary Digital Life team. Many of the 3D models released today were created with a new photogrammetry rig created by UMass Amherst undergraduate Trevor Mayhan called the "Beastcam MACRO," customized for small live animals. It is part of the broader Beastcam technology platform designed for rapidly capturing high-resolution, full-color 3D models of living organisms, Irschick explains. The Digital Life team is using this technology to create accurate, high-resolution models of all life on earth. Tatjana Dzambazova of the 3D design and software firm Autodesk, Inc. and a member of the Digital Life advisory committee, says the 3D models already captured - of frogs, sharks, scorpions, toads, lizards, flowers and invertebrates—can be useful as educational tools in virtual reality or in other computer software, and can be 3D printed to educate children about animal diversity. Also, models can benefit scientists because they represent true-to-life digital replicas of live organisms, enabling a range of new scientific inquiries. "Imagine a comprehensive, true-to-life 3D library of all the existing species in the world available online to anyone. With technology developed by Digital Life and accessible tools such as Autodesk ReMake, technology today can help us understand and appreciate the natural world around us in a new way," she adds. Digital Life's new online 3D frog images include some of the rarest frogs on earth, such as the Panamanian golden frog, Atelopus zeteki, as well as more common species such as the horned frog Ceratophrys. They were scanned in the field in the Philippines by researchers from the University of Oklahoma, as well as at Zoo Atlanta, the Amphibian Foundation and at UMass Amherst. Their photogrammetric process integrates 2D digital photos into 3D models using software such as ReMake. Digital Life director Irschick explains that he and his team hope that making 3D models of living animals will promote conservation, science and research, and public awareness, not only for endangered species but for more common ones that are crucial to ecosystems around the world. "In a race against time, I believe that Digital Life has taken a large step forward in preserving the heritage of these frogs," says photographer Christine Shepard, a member of the Digital Life team. Mark Mandica, executive director of the Amphibian Foundation, a partner on the Frogs of the World project, says the models will provide needed support for the worldwide effort to conserve frog species. The amphibians represent a good test case for the Digital Life's project, he adds. "Aside from frogs facing global population declines, they represent some of the greatest biodiversity the earth has to offer. Frogs are virtually limitless in color and pattern variation, as well as shapes and sizes," he notes. Joseph Mendelson, director of research at Zoo Atlanta, points out that approximately 38 percent of all amphibians face significant threats from development, climate change or the chytrid fungus. Cameron Siler at the University of Oklahoma adds, "In addition to their conservation value, these models show the promise of using 3D technology to digitally preserve specimens for biodiversity and museum-based research." Explore further: New 'digital life' initiative aims to create 3-D models of all living creatures


News Article | May 15, 2017
Site: www.eurekalert.org

Main goal is to develop new methods and tools any country can use to monitor and advance national reproductive health AMHERST, Mass. - Biostatistics expert Leontine Alkema at the School of Public Health and Health Sciences at the University of Massachusetts Amherst recently was awarded a three-year, $1.4 million grant from the Bill & Melinda Gates Foundation to explore and analyze family planning indicators such as contraceptive use in 69 countries. The main goal is to develop new methods and tools any country can use to monitor and advance national reproductive health. Improving access to reproductive health services and products is central to a nation's development, Alkema and colleagues point out. To date, most efforts to monitor progress have focused on national estimates, "but such analyses can mask local disparities," Alkema says. Knowing what is going on within a country at the provincial or district level, for example, is important for programming, she explains. "This grant will help to provide more detailed family planning information at the subnational level using statistical models," focusing at first on a subset of countries and expanding later to all 69 nations. Alkema's involvement in the estimation of family planning indicators started with developing a statistical model to produce national-level estimates for all countries in the world in collaboration with the United Nations Population Division. She says, "Our modeling work on family planning indicators coincided with the start of Family Planning 2020 (FP2020), a global initiative to expand access to family planning services in the world's 69 poorest countries." To aid in monitoring progress, in particular by FP2020 monitoring and evaluation officers in each country, Alkema and colleagues developed an online web application called the Family Planning Estimation Tool (FPET), now being used in national workshops and for FP2020 reporting. "While monitoring at national levels is important for tracking progress, such analyses may mask subnational disparities, or not provide useful information to countries for subnational programming. Hence we started exploring how to obtain information at subnational levels," Alkema explains. Most recently, she and colleagues used FPET for a subnational analysis in India to analyze and report province-level results on trends in contraceptive demand and use, and unmet need for family planning. She says, "The subnational analysis in India showed great disparities. For example, we found that the percentage of married women who indicate that they do not want more children, or would like to wait before having their next child but are not using any contraceptive method, ranged from 6 to 40 percent." The grant from the Bill & Melinda Gates Foundation allows Alkema, her UMass Amherst collaborator Krista Gile and others to develop new methods to assess levels and trends in family planning indicators for smaller subnational populations. The end product will include a tool that can be used for in-country monitoring of contraceptive use as well as the total demand and unmet need for modern methods. "In addition to the challenge of producing estimates of contraceptive use, we will also address the challenge of assessing the size of the population of interest, which are women of reproductive age." Alkema explains. This information can be obtained from censuses but censuses, when they are done, are generally carried out only every 10 years. "The estimation of subnational population sizes in between census years, and for years past a census is another problem to tackle using statistical models." "To move towards the goal of providing every woman with access to the contraceptive method of her choice, we need better monitoring of family planning indicators, and for that, we need statistical methods." according to Alkema. "I am grateful for the support from the Bill & Melinda Gates Foundation to focus on the stats part of this important goal."


News Article | May 23, 2017
Site: www.chromatographytechniques.com

A lightweight, comfortable jacket that can generate the power to light up a jogger at night may sound futuristic, but materials scientist Trisha Andrew at the University of Massachusetts Amherst could make one today. In a new paper this month, she and colleagues outline how they have invented a way to apply breathable, pliable, metal-free electrodes to fabric and off-the-shelf clothing so it feels good to the touch and also transports enough electricity to power small electronics. "Our lab works on textile electronics. We aim to build up the materials science so you can give us any garment you want, any fabric, any weave type, and turn it into a conductor. Such conducting textiles can then be built up into sophisticated electronics," said Andrew. "One such application is to harvest body motion energy and convert it into electricity in such a way that every time you move, it generates power." Powering advanced fabrics that can monitor health data remotely are important to the military and increasingly valued by the health care industry, she notes. Generating small electric currents through relative movement of layers is called triboelectric charging, explains Andrew, who trained as a polymer chemist and electrical engineer. Materials can become electrically charged as they create friction by moving against a different material, like rubbing a comb on a sweater. "By sandwiching layers of differently materials between two conducting electrodes, a few microwatts of power can be generated when we move," she adds. In the current early online edition of Advanced Functional Materials, she and postdoctoral researcher Lu Shuai Zhang in her lab describe the vapor deposition method they use to coat fabrics with a conducting polymer, poly(3,4-ethylenedioxytiophene) also known as PEDOT, to make plain-woven, conducting fabrics that are resistant to stretching and wear and remain stable after washing and ironing. The thickest coating they put down is about 500 nanometers, or about 1/10 the diameter of a human hair, which retains a fabric's hand feel. The authors report results of testing electrical conductivity, fabric stability, chemical and mechanical stability of PEDOT films and textile parameter effects on conductivity for 14 fabrics, including five cottons with different weaves, linen and silk from a craft store. "Our article describes the materials science needed to make these robust conductors," Andrew says. "We show them to be stable to washing, rubbing, human sweat and a lot of wear and tear." PEDOT coating did not change the feel of any fabric as determined by touch with bare hands before and after coating. Coating did not increase fabric weight by more than two percent. The work was supported by the Air Force Office of Scientific Research. Until recently, she and Zhang point out, textile scientists have tended not to use vapor deposition because of technical difficulties and high cost of scaling up from the laboratory. But over the last 10 years, industries such as carpet manufacturers and mechanical component makers have shown that the technology can be scaled up and remain cost-effective. The researchers say their invention also overcomes the obstacle of power-generating electronics mounted on plastic or cladded, veneer-like fibers that make garments heavier and/or less flexible than off-the-shelf clothing "no matter how thin or flexible these device arrays are." "There is strong motivation to use something that is already familiar, such as cotton/silk thread, fabrics and clothes, and imperceptibly adapting it to a new technological application." Andrew adds, "This is a huge leap for consumer products, if you don't have to convince people to wear something different than what they are already wearing." "You'd be amazed how much stress your clothes go through until you try to make a coating that will survive a shirt being pulled over the head. The stress can be huge, up to a thousand newtons of force. For comparison, one footstep is equal to about 10 newtons, so it's yanking hard. If your coating is not stable, a single pull like that will flake it all off. That's why we had to show that we could bend it, rub it and torture it. That is a very powerful requirement to move forward." Andrew is director of wearable electronics at the Center for Personalized Health Monitoring in UMass Amherst's Institute of Applied Life Sciences (IALS). Since the basic work reported this month was completed, her lab has also made a wearable heart rate monitor with an off-the-shelf fitness bra to which they added eight monitoring electrodes. They will soon test it with volunteers on a treadmill at the IALS human movement facility. She explains that a hospital heart rate monitor has 12 electrodes, while the wrist-worn fitness devices popular today have one, which makes them prone to false positives. They will be testing a bra with eight electrodes, alone and worn with leggings that add four more, against a control to see if sensors can match the accuracy and sensitivity of what a hospital can do. As the authors note in their paper, flexible, body-worn electronics represent a frontier of human interface devices that make advanced physiological and performance monitoring possible. For the future, Andrew says, "We're working on taking any garment you give us and turning it into a solar cell so that as you are walking around the sunlight that hits your clothes can be stored in a battery or be plugged in to power a small electronic device." Zhang and Andrew believe their vapor coating is able to stick to fabrics by a process called surface grafting, which takes advantage of free bonds dangling on the surface chemically bonding to one end of the polymer coating, but they have yet to investigate this fully.


News Article | May 25, 2017
Site: www.sciencedaily.com

A lightweight, comfortable jacket that can generate the power to light up a jogger at night may sound futuristic, but materials scientist Trisha Andrew at the University of Massachusetts Amherst could make one today. In a new paper this month, she and colleagues outline how they have invented a way to apply breathable, pliable, metal-free electrodes to fabric and off-the-shelf clothing so it feels good to the touch and also transports enough electricity to power small electronics. She says, "Our lab works on textile electronics. We aim to build up the materials science so you can give us any garment you want, any fabric, any weave type, and turn it into a conductor. Such conducting textiles can then be built up into sophisticated electronics. One such application is to harvest body motion energy and convert it into electricity in such a way that every time you move, it generates power." Powering advanced fabrics that can monitor health data remotely are important to the military and increasingly valued by the health care industry, she notes. Generating small electric currents through relative movement of layers is called triboelectric charging, explains Andrew, who trained as a polymer chemist and electrical engineer. Materials can become electrically charged as they create friction by moving against a different material, like rubbing a comb on a sweater. "By sandwiching layers of differently materials between two conducting electrodes, a few microwatts of power can be generated when we move," she adds. In the current early online edition of Advanced Functional Materials, she and postdoctoral researcher Lu Shuai Zhang in her lab describe the vapor deposition method they use to coat fabrics with a conducting polymer, poly(3,4-ethylenedioxytiophene) also known as PEDOT, to make plain-woven, conducting fabrics that are resistant to stretching and wear and remain stable after washing and ironing. The thickest coating they put down is about 500 nanometers, or about 1/10 the diameter of a human hair, which retains a fabric's hand feel. The authors report results of testing electrical conductivity, fabric stability, chemical and mechanical stability of PEDOT films and textile parameter effects on conductivity for 14 fabrics, including five cottons with different weaves, linen and silk from a craft store. "Our article describes the materials science needed to make these robust conductors," Andrew says. "We show them to be stable to washing, rubbing, human sweat and a lot of wear and tear." PEDOT coating did not change the feel of any fabric as determined by touch with bare hands before and after coating. Coating did not increase fabric weight by more than 2 percent. The work was supported by the Air Force Office of Scientific Research. Until recently, she and Zhang point out, textile scientists have tended not to use vapor deposition because of technical difficulties and high cost of scaling up from the laboratory. But over the last 10 years, industries such as carpet manufacturers and mechanical component makers have shown that the technology can be scaled up and remain cost-effective. The researchers say their invention also overcomes the obstacle of power-generating electronics mounted on plastic or cladded, veneer-like fibers that make garments heavier and/or less flexible than off-the-shelf clothing "no matter how thin or flexible these device arrays are." "There is strong motivation to use something that is already familiar, such as cotton/silk thread, fabrics and clothes, and imperceptibly adapting it to a new technological application." Andrew adds, "This is a huge leap for consumer products, if you don't have to convince people to wear something different than what they are already wearing." Test results were sometimes a surprise, Andrew notes. "You'd be amazed how much stress your clothes go through until you try to make a coating that will survive a shirt being pulled over the head. The stress can be huge, up to a thousand newtons of force. For comparison, one footstep is equal to about 10 newtons, so it's yanking hard. If your coating is not stable, a single pull like that will flake it all off. That's why we had to show that we could bend it, rub it and torture it. That is a very powerful requirement to move forward." Andrew is director of wearable electronics at the Center for Personalized Health Monitoring in UMass Amherst's Institute of Applied Life Sciences (IALS). Since the basic work reported this month was completed, her lab has also made a wearable heart rate monitor with an off-the-shelf fitness bra to which they added eight monitoring electrodes. They will soon test it with volunteers on a treadmill at the IALS human movement facility. She explains that a hospital heart rate monitor has 12 electrodes, while the wrist-worn fitness devices popular today have one, which makes them prone to false positives. They will be testing a bra with eight electrodes, alone and worn with leggings that add four more, against a control to see if sensors can match the accuracy and sensitivity of what a hospital can do. As the authors note in their paper, flexible, body-worn electronics represent a frontier of human interface devices that make advanced physiological and performance monitoring possible. For the future, Andrew says, "We're working on taking any garment you give us and turning it into a solar cell so that as you are walking around the sunlight that hits your clothes can be stored in a battery or be plugged in to power a small electronic device." Zhang and Andrew believe their vapor coating is able to stick to fabrics by a process called surface grafting, which takes advantage of free bonds dangling on the surface chemically bonding to one end of the polymer coating, but they have yet to investigate this fully.


News Article | May 9, 2017
Site: www.eurekalert.org

AMHERST, Mass. - The National Fish, Wildlife and Plants Climate Adaptation Strategy working group announced May 8 that it has selected the Massachusetts Wildlife Climate Action Tool to receive its 2017 Climate Adaptation Leadership Award for Natural Resources in the "broad partnership" category. It recognizes the partners for "demonstrating exemplary leadership in reducing climate-related threats and promoting adaptation of the nation's natural resources." The honor is one of eight national awards announced yesterday at the National Adaptation Forum in St. Paul, Minn. In its citation, the working group noted that the Massachusetts Wildlife Climate Action Tool "inspires action to protect natural resources and help them adapt in a changing climate." Though designed for Massachusetts, the tool launched in 2015 offers "broadly relevant information and could serve as a model" for many other states, the working group noted. It is intended to help decision-makers, conservation groups and managers find information on climate change impacts and the vulnerabilities of fish and wildlife species and their habitats. The team that developed the online climate action tool included extension associate professor of environmental conservation Scott Jackson, Michelle Staudinger, adjunct professor of environmental conservation and science coordinator of the Northeast Climate Science Center, and project manager Melissa Ocana, all at UMass Amherst, and Massachusetts Division of Fisheries and Wildlife biologist John O'Leary. Staudinger says, "There are actions we can take now to adapt to climate change and protect fish, wildlife and their habitats, as well as help human communities increase their resilience to better cope with these changes. This tool is designed to inform and inspire local action to protect the Commonwealth's natural resources including species of greatest conservation need." Tool users can explore adaptation strategies and actions to maintain healthy, resilient natural communities in the face of climate change. The tool synthesizes the best available science, providing information on climate change impacts with projections for over 30 variables, vulnerability assessments for fish and wildlife species and habitats, information about non-climate stressors such as development and loss of landscape connectivity that must be accounted for, and on-the-ground actions including forestry practices, land protection and restoring wildlife movement corridors through landscape connectivity. The tool highlights challenges for such iconic species as brook trout that are affected by warming stream temperatures and fragmented habitat, marbled salamanders affected by changing rainfall patterns, piping plover and other coastal shorebirds susceptible to sea-level rise and storm events and beech-birch-maple forests where warming temperatures affect sugar maples and other northern trees. Melissa Ocana, project manager in the department of environmental conservation at UMass Amherst, says "We've built a dynamic platform where we can showcase the best available science and case studies of adaptation action from partners across Massachusetts. Now, partners and experts can help us continue to populate the tool with new information and success stories as they develop." The climate action tool was developed by scientists at the Massachusetts Division of Fisheries and Wildlife, UMass Amherst's Center for Agriculture, Food and the Environment and its Department of Interior Northeast Climate Science Center, and the U.S. Geological Survey's Massachusetts Cooperative Fish and Wildlife Research Unit. In addition to the National Fish, Wildlife and Plants Climate Adaptation Strategy working group, the award is sponsored by the Natural Resource Conservation Service, National Oceanic and Atmospheric Administration, U.S.D.A. Forest Service and the Association of Fish and Wildlife Agencies.


News Article | September 15, 2017
Site: www.eurekalert.org

UMass Amherst researchers plan to develop a new computational tool that will help researchers in interpreting fMRI of the brain and improve accuracy in relating fMRI data to neural responses in the brain AMHERST, Mass. - Cognitive neuroscientists Rosie Cowell and David Huber at the University of Massachusetts Amherst recently received a four-year, $2.36 million grant from the National Institutes of Health to develop a new computational tool that will help researchers in interpreting functional magnetic resonance images (fMRI) of the brain and improve accuracy in relating fMRI data to neural responses in the brain. Cowell says, "Right now it can be difficult to relate fMRI data to the underlying brain activations to see how different groups of neurons are responding when a person is performing a task. This is because, with the methods we have now, the signal is averaged across too many neurons, millions of them at once. Even the narrowest view we can achieve is too coarse; you can't see how smaller subsets of neurons are behaving." Huber adds, "Our goal is to develop a mathematical tool for more accurately interpreting fMRI in a more fine-grained way. This is a computational technique that will be useful for researchers to understand what's going on the brain. We hope to fully develop and validate this technique and provide software that other fMRI researchers throughout the world can use, with publications on how to use it and when, that is, what types of experiments it is best suited for." The neuroscientists will use the campus's new MRI scanner at the Institute for Applied Life Sciences to compare their computational models of the brain with what happens in the visual cortex when people view different visual stimuli. Their co-investigators on the grant are John Serences at the University of California, San Diego, and Earl Miller at MIT. Cowell and Huber's "Foundations of Non-Invasive Functional Human Brain Imaging and Recording" grant is part of former President Obama's Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative, launched in 2013 to "revolutionize understanding of the human brain" by accelerating the development and application of new technologies and tools for treating and preventing brain disorders. A major goal is to "produce a new dynamic picture of the brain that, for the first time, will show how individual cells and complex neural circuits interact in both time and space." As Cowell explains, "With fMRI you can see what different parts of the brain are doing when it is performing a task, for example, paying attention to the orientation of a straight line viewed on a screen." Scientists already know that certain groups of neurons "light up" predictably in response to a seeing a horizontal line, but those same neurons remain quiet when presented with a vertical line. The 1960s discovery of this in cat neurons led to a Nobel Prize, she notes. "It's called orientation tuning," Cowell adds, "and these types of experiments are rarely carried out in humans because except in very unusual circumstances we do not put electrodes into peoples' brains for research. And our current fMRI methods don't allow us to measure brain activation with the kind of spatial resolution that would be required to link the stimulus with the neural responses. We just see neural responses aggregated over too many millions of neurons." "The ultimate goal of the project is to be able to use fMRI to discover how neurons' responses change with certain changes in our mental circumstances," she notes. For example, "Does the way in which a neuron responds to an oriented line change if you are paying attention to the line, compared to when you are ignoring it? These kinds of questions will tell us about the mechanisms of cognition." Huber suggests that the problem can be thought of as similar to interpreting election results. "If all you know is that candidate A narrowly won, you have no idea how different groups voted, whether one group voted in a landslide for candidate A while the other groups narrowly preferred candidate B, or whether all groups had a slight preference for candidate A. Well, with current fMRI methods, researchers can only know how millions of neurons responded to a stimulus on average. It's a very coarse measure," he notes. "The computational technique we're developing allows us to break those millions of neurons into pools, so we can narrow the response down and know more about how smaller groups of neurons are behaving. We'll be applying mathematical modeling figure out how different parts of the population are responding," Huber adds. "If you collect enough brain data by presenting lots of different line orientations to people while they're in the scanner, and use our mathematical method to analyze the data, you get a more accurate picture of different clusters and what they are doing. Our technique uses the numbers that roll off the scanner to infer what is going on. The large amount of data allows you to break it down more finely, and the more orientations we test, the more precise we can be," he says. They will also take advantage of previously collected data from monkeys as they viewed visual stimuli while researchers recorded neuronal activity in their brains using electrodes. Cowell and Huber will compare those laboratory experimental results with the output of their computational tool to evaluate how well the mathematical model is performing. The researchers say this work "will advance our ability to accurately and precisely infer the properties of neural-level responses from data obtained via non-invasive fMRI in humans."


Sievert L.L.,UMass Amherst
American Journal of Human Biology | Year: 2013

Up to 75% of women in the US report having experienced hot flashes during the menopausal transition. The purpose of this review is to describe the physiology of hot flashes, and the ways in which hot flashes have been examined by subjective report and by objective measurement. Hot flashes occur because of an activation of the heat dissipation response, possibly triggered by a hypothalamic mechanism within the context of declining estrogen levels. There is cross-population variation in the frequency of self-reported hot flashes, although cross-study comparisons are problematic because of incompatibilities in study design. Diaries are a good way to collect information on the time and severity of hot flashes, and body diagrams allow researchers to study the pattern of heat and sweating. Hot flashes can be objectively measured by increases in heart rate, finger blood flow, respiratory exchange ratio, skin temperature, and core body temperature. Sternal skin conductance is the method most highly correlated with subjective hot flash report. In a laboratory, concordance between subjective report and sternal skin conductance can approach 100%. Ambulatory monitoring allows for the tracking of hot flashes during a woman's daily routine or sleep; however, concordance is much lower with ambulatory, compared to laboratory, monitoring. The study of hot flashes at menopause provides a model for the study of any experience that can be assessed by both self-report and biometric measurement. © 2013 Wiley Periodicals, Inc.


Objectives: To characterize challenges experienced during stages of female-to-male sex transition and investigate associations between transition-specific measures of psychosocial stress, nocturnal decline in ambulatory blood pressure (amBP), and changes in C-reactive protein (CRP) levels. Methods: For this biocultural study, 65 healthy transmen who were using testosterone (T) therapy participated in interviews to assess transition-specific stress experience. They provided perceived stress scores, self-esteem scores, 24-h amBP measures, salivary samples for T levels, and a blood spot for CRP levels. Psychosocial stress was examined in relation to amBP and CRP using linear regression while adjusting for age, body mass index, and smoking. Results: There were no differences in mean levels of amBP in association with stage of transition. Men reporting stress associated with being "out" as transgender had significantly diminished nocturnal decline in systolic and diastolic amBP compared to men who did not report such stress. The associations remained significant when examined among men in stages 1 and 2 (≤3 years on T), but not among men in stage 3 (>3 years on T) of transition. Men reporting stress related to "passing" as someone born male had higher CRP levels than those who did not report such stress. The association remained significant when examined among men in stages 2 and 3 (>0.5-3 years on T). Conclusion: Measures of stress that captured individuals' experiences of gender liminality were associated with diminished nocturnal decline in amBP and increased levels of CRP. There are significant differences between men grouped into different stages of the transition process. © 2011 Wiley Periodicals, Inc.


Strain-gated logic devices are important for the development of advanced flexible electronics. Using a dual-monolayer-promoted film-transfer technique, a flexible multilayer structure capable of undergoing large compressive deformation was prepared. Formation of a crease in the gap between electrodes at a geometrically tunable strain leads to formation of an electrical connection in a reversible and reproducible fashion. A strain-gated electrical switch includes at least two conductive electrodes disposed on a surface of an elastomer substrate, the at least two conductive electrodes forming a gap between the at least two electrodes in an off-state of the strain-gated electrical switch, the gap diminishing under compressive strain to form a crease, the compressive strain pressing the at least two electrodes into contact with each other in an on-state of the strain-gated electrical switch.

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