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  • richardmitnick 12:04 pm on December 5, 2018 Permalink | Reply
    Tags: 'Dim the Sun', A high-altitude balloon will fly up to the stratosphere at an altitude of about 20 kilometres and release a small aerosol plume of calcium carbonate, Harvard Scientists Will Actually Launch a Geoengineering Experiment Next Year, Harvard University, , SCoPEx   

    From Harvard Astronomy via Science Alert: “Harvard Scientists Will Actually Launch a Geoengineering Experiment Next Year” 

    Harvard Astronomy Banner
    From Harvard Astronomy

    via

    Science Alert

    1
    (Johnson Space Centre/NASA)

    4 DEC 2018
    PETER DOCKRILL

    Last month, new research from Harvard and Yale led to a flurry of news claiming scientists were proposing to ‘dim the Sun’ [Environmental Research Letters] in an “ingenious but as-yet-unproven way to tackle climate change”.

    Only, they weren’t. As other outlets made clear, the paper was actually an analysis of whether solar geoengineering is technically and economically feasible, nothing more.

    The funny thing is, though, those overblown headlines almost did get it right after all, even if only by accident.

    As it happens, other Harvard scientists are indeed moving ahead with a groundbreaking plan to test the effects of solar geoengineering in the skies above our heads, and their US$3 million experiment could begin as early as next year [Nature].

    The project – called the Stratospheric Controlled Perturbation Experiment (SCoPEx) – is part of Harvard’s Solar Geoengineering Research Program.

    While most studies looking at the effects of spraying chemicals into the atmosphere to cool the planet rely on computer simulations to test their hypotheses, SCoPEx will conduct its testing in the real world.

    In the experiment, a high-altitude balloon will fly up to the stratosphere, at an altitude of about 20 kilometres, and release a small aerosol plume of calcium carbonate.

    Once the chemical payload is released, it’s expected to disperse into a perturbed air mass about 1 kilometre long and 100 metres in diameter. The balloon will then fly back and forth through this cloud repeatedly for about 24 hours, analysing the particles’ behaviour and evolution in the sky.

    The reason we might want to do this is to see whether sunlight-reflecting particles in the atmosphere could cool down the surface of the planet, in an intentionally contrived recreation of the effects of a volcano eruption – most notably, the observed global cooling effects of the Mount Pinatubo eruption in 1991.

    But solar geoengineering is not without its controversies. Some studies suggest spraying huge amounts of sunlight-reflecting particles into the atmosphere could have grave consequences, leading to unintended issues for things like crops, weather patterns, or the ozone layer.

    The ozone layer in particular is one of the reasons the team behind SCoPEx is working with calcium carbonate – because their previous research indicated it could be the safest in terms of stratospheric chemistry.

    That said, there’s still a huge amount we don’t know about what solar geoengineering might unleash, which is all the more reason to conduct small-scale experiments like SCoPEx, which will only release about the same amount of particulate as one minute of commercial airliner emissions.

    “There are all of these downstream effects that we don’t fully understand,” atmospheric chemist and SCoPEx principal investigator Frank Keutsch told Nature.

    As always, even if the experiments prove successful – and demonstrate that solar geoengineering is something we could potentially roll out on a larger scale – it’s not a silver bullet for global warming.

    Drastically reducing existing levels of carbon emissions should still be humanity’s first response to climate change, because that’s the root cause of our heat-trapping problems – and solar geoengineering won’t be able to help other related issues, like ocean acidification.

    “Solar reengineering is a supplement, and in the end we still have to cut emissions,” one of the team, applied physicist David Keith, said in 2016.

    While the world takes care of that, scientists will be testing just what this supplement is capable of, and from the sounds of it, we won’t have to wait too long to find out if ‘dimming the Sun’ can help us.

    A 2014 paper on the SCoPEx research is available here.

    See the full article here .

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  • richardmitnick 12:24 pm on September 27, 2018 Permalink | Reply
    Tags: April Boin Choi, , Harvard University,   

    From Harvard University: Women in STEM – “Silent Infant Gestures May Help Detect Autism” April Boin Choi 

    Harvard University
    From Harvard University

    September 25, 2018
    Andrew Bauld

    1
    With her research, Ph.D. candidate April Boin Choi looks to identify ways to increase early detection of autism in infants.

    Autism affects tens of millions of individuals around the world, but the ability to detect the disorder in young children remains nearly impossible. That may change, thanks in part to the research of Ph.D. candidate April Boin Choi, who has spent her early career studying the disorder and believes that doctors might one day be able to diagnose autism starting in infancy.

    Choi, Ed.M.’13, began researching autism first as an undergraduate studying neuroscience. She was frustrated by the lack of ability to apply her research directly to individuals with autism, and her desire to bridge science, education, and psychology led her to the Mind, Brain, and Education master’s program.

    Now, in the fifth year of the Ph.D. Program, Choi is working to develop better ways of identifying the development of autism in young children, particularly in children who have an older sibling with autism and who are themselves at higher risk of developing the disorder.

    “Autism affects about 1 percent of the general population. For at-risk children, that number jumps to 20 percent,” says Choi, who believes the average age for detection of autism in children — around age 4 — is too late. “It means that those children may not have the access to resources and support that are especially critical during the earliest years of life,” she explains.

    As a possible pathway to earlier diagnosis, Choi is examining forms of communication, specifically hand gestures. Although researchers have long studied gesturing in preverbal children, less is known about gesturing in high-risk populations. Working in the Boston Children’s Hospital Lab of Cognitive Neuroscience, directed by Professor Charles Nelson, Choi has been able to study a cohort of infants at high risk for developing autism.

    “We found that high-risk infants produce fewer gestures, and that infants with fewer gestures at age 1 were later found to have more language difficulties by age 2 and were more likely to receive autism diagnoses,” says Choi.

    Even in the hands of a skilled clinician, says Nelson, reliably diagnosing autism in children under two years of age is next to impossible. “April has convincingly shown that before the infant’s first birthday they are already showing early motor signs of the disorder,” he says. “If April’s work can be replicated with a larger sample size and perhaps in low-risk infants as well, it may well pave the way for clinicians to identify infants who will develop autism before their first birthday.”

    Nelson isn’t the only one who believes in Choi’s work. In April, she received one of three fellowships through the Novak Djokovic Foundation and the Center on the Developing Child at Harvard. The 2018–2019 grant, which begins this fall, will support her “ground-breaking research,” according to the foundation.

    “This fellowship is unique,” says Choi, “because it brings together students from different disciplines for yearlong skill-building workshops and a chance to receive feedback on research from faculty from across the university.”

    Through the fellowship, Choi is excited to build interdisciplinary thinking skills and translate her science-based research to a wide range of stakeholders, especially for children and families back home in Korea, where she plans to return after her dissertation.

    Despite the fact that nearly 1 in 38 children in Korea is diagnosed with autism, one of the highest rates in the world, there is still a massive stigma attached to the disorder there, resulting in under-diagnosing and fewer support resources for families. Children also report high levels of social exclusion and bullying. There is also a personal motivation for Choi, as she has a close family member with autism in Korea.

    “Having a family member [with autism] instilled in me the commitment to work with autistic students and the core belief that all students can reach their full potential through quality education,” she says.

    Choi says she hopes her research can continue to bridge the gap between autism research and the negative cultural stigma that still exists around the disorder.

    “I want to work in the research world and the outreach world, to hopefully positively impact students and families with autism in Korea and around the world,” Choi says.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Harvard University campus
    Harvard is the oldest institution of higher education in the United States, established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. It was named after the College’s first benefactor, the young minister John Harvard of Charlestown, who upon his death in 1638 left his library and half his estate to the institution. A statue of John Harvard stands today in front of University Hall in Harvard Yard, and is perhaps the University’s best known landmark.

    Harvard University has 12 degree-granting Schools in addition to the Radcliffe Institute for Advanced Study. The University has grown from nine students with a single master to an enrollment of more than 20,000 degree candidates including undergraduate, graduate, and professional students. There are more than 360,000 living alumni in the U.S. and over 190 other countries.

     
  • richardmitnick 11:31 am on September 4, 2018 Permalink | Reply
    Tags: Aftershocks can often be as horrifying as the main event, , , Harvard University, , , , , This New AI Tool Could Solve a Deadly Earthquake Problem We Currently Can't Fix   

    From Harvard University via Science Alert: “This New AI Tool Could Solve a Deadly Earthquake Problem We Currently Can’t Fix” 

    Harvard University
    From Harvard University

    via

    Science Alert

    4 SEP 2018
    DAVID NIELD

    1
    (mehmetakgu/iStock)

    It could literally save lives.

    The aftershocks of a devastating earthquake can often be as horrifying as the main event. Now scientists have developed a system for predicting where such post-quake tremors could take place, and they’ve used an ingenious application of artificial intelligence (AI) to make this happen.

    Knowing more about what’s coming next can be a matter of life or death for communities reeling from a large quake. The aftershocks can often cause further injuries and fatalities, damage buildings, and complicate rescue efforts.

    A team led by researchers from Harvard University has trained AI to crunch huge amounts of sensor data and apply deep learning to make more accurate predictions.

    The researchers behind the new system say it’s not ready to be deployed yet, but is already more reliable at pinpointing aftershocks than current prediction models.

    In the years ahead, it could become a vital part of the prediction systems used by seismologists.

    “There are three things you want to know about earthquakes – you want to know when they are going to occur, how big they’re going to be and where they’re going to be,” says one of the team, Brendan Meade from Harvard University in Massachusetts.

    “Prior to this work we had empirical laws for when they would occur and how big they were going to be, and now we’re working the third leg, where they might occur.”

    The idea to use deep learning to tackle this came to Meade when he was on a sabbatical at Google – a company where AI is being deployed in many different areas of computing and science.

    Machine learning is just one facet of AI, and is exactly what it sounds like: machines learning from sets of data, so they can cope with new problems that they haven’t been specifically programmed to tackle.

    Deep learning is a more advanced type of machine learning, applying what are called neural networks to try and mimic the thinking processes of the brain.

    In simple terms it means the AI can see more possible results at once, and weigh up a more complex map of factors and considerations, sort-of like neurons in a brain would.

    It’s perfect for earthquakes, with so many variables to consider – from the strength of the shock to the position of the tectonic plates to the type of ground involved. Deep learning could potentially tease out patterns that human analysts could never spot.

    To put this to use with aftershocks, Meade and his colleagues tapped into a database of over 131,000 pairs of earthquake and aftershock readings, taken from 199 previous earthquakes.

    Having let the AI engine chew through those, they then got it to predict the activity of more than 30,000 similar pairs, suggesting the likelihood of aftershocks hitting locations based on a grid of 5 square kilometre (1.9 square mile) units.

    The results were ahead of the Coulomb failure stress change model currently in use. If 1 represents perfect accuracy, and .5 represents flipping a coin, the Coulomb model scored 0.583, and the new AI system managed 0.849.

    “I’m very excited for the potential for machine learning going forward with these kind of problems – it’s a very important problem to go after,” says one of the researchers, Phoebe DeVries from Harvard University.

    “Aftershock forecasting in particular is a challenge that’s well-suited to machine learning because there are so many physical phenomena that could influence aftershock behaviour and machine learning is extremely good at teasing out those relationships.”

    A key ingredient, the researchers say, was the addition of the von Mises yield criterion into the AI’s algorithms – a calculation that can predict when materials will break under stress. Previously used in fields like metallurgy, the calculation hasn’t been extensively used in modelling earthquakes before now.

    There’s still a way to go here – the researchers point out their current AI models are only designed to deal with one type of aftershock trigger, and simple fault lines: it’s not yet a system that can be applied to any kind of quake around the world.

    What’s more, it’s too slow right now to predict the deadly aftershocks that can happen a day or two after the first earthquake.

    However, the good news is that neural networks are designed to continually get better over time, which means with more data and more learning cycles, the system should steadily improve.

    “I think we’ve really just scratched the surface of what could be done with aftershock forecasting… and that’s really exciting,” says DeVries.

    The research has been published in Nature.

    See the full article here .

    Earthquake Alert

    1

    Earthquake Alert

    Earthquake Network projectEarthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

    3
    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Harvard University campus
    Harvard is the oldest institution of higher education in the United States, established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. It was named after the College’s first benefactor, the young minister John Harvard of Charlestown, who upon his death in 1638 left his library and half his estate to the institution. A statue of John Harvard stands today in front of University Hall in Harvard Yard, and is perhaps the University’s best known landmark.

    Harvard University has 12 degree-granting Schools in addition to the Radcliffe Institute for Advanced Study. The University has grown from nine students with a single master to an enrollment of more than 20,000 degree candidates including undergraduate, graduate, and professional students. There are more than 360,000 living alumni in the U.S. and over 190 other countries.

     
  • richardmitnick 2:34 pm on April 14, 2018 Permalink | Reply
    Tags: , Harvard University, Laser 'tweezers', ,   

    From Harvard via Science Alert: “Scientists Just Achieved The World’s Most Precise Chemical Reaction” 

    Harvard University
    Harvard University

    Science Alert

    13 APR 2018
    MIKE MCRAE

    1
    (johnason/istock)

    Scientists have just performed the world’s most precisely controlled chemical reaction, sticking together just two atoms from elements that wouldn’t normally form a molecule.

    The two elements – sodium and caesium – produced an interesting alloy-like molecule. On top of that, this method of creation could set the way of making just the kind of materials we might need in future technology.

    A team of Harvard University scientists used laser ‘tweezers’ to manipulate individual atoms of the two alkali metals into close proximity, and provided a photon to help them bond into a single molecule.

    Chemical reactions are usually hit-and-miss affairs, where vast numbers of atoms are thrown together under the right conditions, and probability does the rest.

    This ‘stochastic’ method of chemical reactions is all well and good if the combination of elements are a decent match. But when scientists want a really exotic pairing, they need to get creative.

    Sodium (Na) and caesium (Cs) are both found in the same group on the periodic table – as you may remember from high school chemistry, it means they tend to have similar reactive properties.

    Periodic table Sept 2017. Wikipedia

    They also don’t tend to bump into each other and easily bond as a molecule.

    Which is really a shame – the polarised electrical properties of a molecule of NaCs would make it super useful for storing quantum ‘qubit’ states of superposition that can also interact easily with other components.

    This all-in-one combination of qubit storage plus interaction is something desperately needed in future technology.

    “The direction of quantum information processing is one of the things we’re excited about,” says lead researcher and chemist Kang-Kuen Ni.

    Improbable doesn’t mean impossible, though: if these two atoms happen to be close enough with the right energy, a connection can form.

    To achieve this perfect mix of energy and timing, the researchers held single atoms in overlapping magneto-optical traps and pelted them with photons to cool them down to a fraction of a degree above absolute zero.

    Meanwhile, they used a pair of lasers tuned to create an electrical effect, causing each atom to move towards each laser’s focus, as if they were pulled into two sci-fi tractor beams.

    Nearby, the two atoms can collide easily. This still doesn’t necessarily guarantee they’ll bond, given the need to conserve the right momentum and energy levels.

    It’s a tricky juggle of conditions, one the researchers managed using the right laser pulses.

    The end result is a brief flicker of a bond between two atoms in the same quantum state, providing the researchers with details on what’s happening on an extremely fine level.

    Ni says the next step would be to create longer lasting molecules by combining them while in a ground state, rather than an excited one.

    “I think that a lot of scientists will follow, now that we have shown what is possible,” says Ni.

    The ultimate goal would be to tailor the creation of far more complex molecules, making use not only of their classical shapes but creating tiny quantum components for the next generation of computing.

    And for this kind of construction, nothing can be left to sheer chance.

    “The experimental demonstration represents for the first time that a chemical reaction process is deterministically controlled,” Jun Ye of the US National Institute of Standards and Technology told David Bradley from Chemistryworld.

    Though Ye wasn’t part of the study, he expressed excitement over the results.

    “Control of molecular interactions, including reaction, at the most fundamental level has been a long-standing goal in physical science.”

    This research was published in Science.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Harvard University campus
    Harvard is the oldest institution of higher education in the United States, established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. It was named after the College’s first benefactor, the young minister John Harvard of Charlestown, who upon his death in 1638 left his library and half his estate to the institution. A statue of John Harvard stands today in front of University Hall in Harvard Yard, and is perhaps the University’s best known landmark.

    Harvard University has 12 degree-granting Schools in addition to the Radcliffe Institute for Advanced Study. The University has grown from nine students with a single master to an enrollment of more than 20,000 degree candidates including undergraduate, graduate, and professional students. There are more than 360,000 living alumni in the U.S. and over 190 other countries.

     
  • richardmitnick 10:45 am on April 5, 2018 Permalink | Reply
    Tags: A Second 'Big Bang' Could End Our Universe in an Instant, , , Harvard University, , , , , , , Thanks to The Higgs Boson   

    From Harvard via Science Alert: “A Second ‘Big Bang’ Could End Our Universe in an Instant, Thanks to The Higgs Boson” 

    Harvard University
    Harvard University

    ScienceAlert

    Science Alert

    Well, that’s just great.

    1
    A Black Hole Artist Concept. (NASA/JPL-Caltech)

    5 APR 2018
    JEREMY BERKE, BUSINESS INSIDER

    Our universe may end the same way it was created: with a big, sudden bang. That’s according to new research from a group of Harvard physicists, who found that the destabilization of the Higgs boson – a tiny quantum particle that gives other particles mass – could lead to an explosion of energy that would consume everything in the known universe and upend the laws of physics and chemistry.

    As part of their study, published last month in the journal Physical Review D, the researchers calculated when our universe could end.

    It’s nothing to worry about just yet. They settled on a date 10139 years from now, or 10 million trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion years in the future. And they’re at least 95 percent sure – a statistical measure of certainty – that the universe will last at least another 1058 years.

    The Higgs boson, discovered in 2012 by researchers smashing subatomic protons together at the Large Hadron Collider, has a specific mass.

    LHC

    CERN/LHC Map

    CERN LHC Tunnel

    CERN LHC particles

    CERN CMS Higgs Event

    CERN ATLAS Higgs Event

    If the researchers are correct, that mass could change, turning physics on its head and tearing apart the elements that make life possible, according to the New York Post.

    And rather than burning slowly over trillions of years, an unstable Higgs boson could create an instantaneous bang, like the Big Bang that created our universe.

    The researchers say a collapse could be driven by the curvature of space-time around a black hole, somewhere deep in the universe. When space-time curves around super-dense objects, like a black hole, it throws the laws of physics out of whack and causes particles to interact in all sorts of strange ways.

    The researchers say the collapse may have already begun – but we have no way of knowing, as the Higgs boson particle may be far away from where we can analyse it, within our seemingly infinite universe. “It turns out we’re right on the edge between a stable universe and an unstable universe,” Joseph Lykken, a physicist from the Fermi National Accelerator Laboratory who was not involved in the study, told the Post.

    He added: “We’re sort of right on the edge where the universe can last for a long time, but eventually, it should go ‘boom.'”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Harvard University campus
    Harvard is the oldest institution of higher education in the United States, established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. It was named after the College’s first benefactor, the young minister John Harvard of Charlestown, who upon his death in 1638 left his library and half his estate to the institution. A statue of John Harvard stands today in front of University Hall in Harvard Yard, and is perhaps the University’s best known landmark.

    Harvard University has 12 degree-granting Schools in addition to the Radcliffe Institute for Advanced Study. The University has grown from nine students with a single master to an enrollment of more than 20,000 degree candidates including undergraduate, graduate, and professional students. There are more than 360,000 living alumni in the U.S. and over 190 other countries.

     
  • richardmitnick 2:08 pm on January 12, 2018 Permalink | Reply
    Tags: Accelerating light beams in curved space, Acceleration, , Harvard University, , ,   

    From Technion, Harvard and CfA via phys.org: “Accelerating light beams in curved space” 

    Technion bloc

    Technion

    Harvard University

    Harvard University

    Harvard Smithsonian Center for Astrophysics

    Center For Astrophysics

    phys.org

    January 12, 2018
    Lisa Zyga

    1
    The accelerating light beam propagates on a nongeodesic trajectory, rather than the geodesic trajectory taken by a non-accelerating beam. Credit: Patsyk et al. ©2018 American Physical Society

    By shining a laser along the inside shell of an incandescent light bulb, physicists have performed the first experimental demonstration of an accelerating light beam in curved space. Rather than moving along a geodesic trajectory (the shortest path on a curved surface), the accelerating beam bends away from the geodesic trajectory as a result of its acceleration.

    Previously, accelerating light beams have been demonstrated on flat surfaces, on which their acceleration causes them to follow curved trajectories rather than straight lines. Extending accelerating beams to curved surfaces opens the doors to additional possibilities, such as emulating general relativity phenomena (for example, gravitational lensing) with optical devices in the lab.

    The physicists, Anatoly Patsyk, Miguel A. Bandres, and Mordechai Segev at the Technion – Israel Institute of Technology, along with Rivka Bekenstein at Harvard University and the Harvard-Smithsonian Center for Astrophysics, have published a paper on the accelerating light beams in curved space in a recent issue of Physical Review X.

    “This work opens the doors to a new avenue of study in the field of accelerating beams,” Patsyk told Phys.org. “Thus far, accelerating beams were studied only in a medium with a flat geometry, such as flat free space or slab waveguides. In the current work, optical beams follow curved trajectories in a curved medium.”

    In their experiments, the researchers first transformed an ordinary laser beam into an accelerating one by reflecting the laser beam off of a spatial light modulator. As the scientists explain, this imprints a specific wavefront upon the beam. The resulting beam is both accelerating and shape-preserving, meaning it doesn’t spread out as it propagates in a curved medium, like ordinary light beams would do. The accelerating light beam is then launched into the shell of an incandescent light bulb, which was painted to scatter light and make the propagation of the beam visible.

    When moving along the inside of the light bulb, the accelerating beam follows a trajectory that deviates from the geodesic line. For comparison, the researchers also launched a nonaccelerating beam inside the light bulb shell, and observed that that beam follows the geodesic line. By measuring the difference between these two trajectories, the researchers could determine the acceleration of the accelerating beam.

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    (a) Experimental setup, (b) propagation of the green beam inside of the red shell of an incandescent light bulb, and (c) photograph of the lobes of the accelerating beam. Credit: Patsyk et al. ©2018 American Physical Society

    Whereas the trajectory of an accelerating beam on a flat surface is determined entirely by the beam width, the new study shows that the trajectory of an accelerating beam on a spherical surface is determined by both the beam width and the curvature of the surface. As a result, an accelerating beam may change its trajectory, as well as periodically focus and defocus, due to the curvature.

    The ability to accelerate light beams along curved surfaces has a variety of potential applications, one of which is emulating general relativity phenomena.

    “Einstein’s equations of general relativity determine, among other issues, the evolution of electromagnetic waves in curved space,” Patsyk said. “It turns out that the evolution of electromagnetic waves in curved space according to Einstein’s equations is equivalent to the propagation of electromagnetic waves in a material medium described by the electric and magnetic susceptibilities that are allowed to vary in space. This is the foundation of emulating numerous phenomena known from general relativity by the electromagnetic waves propagating in a material medium, giving rise to the emulating effects such as gravitational lensing and Einstein’s rings, gravitational blue shift or red shift, which we have studied in the past, and much more.”

    The results could also offer a new technique for controlling nanoparticles in blood vessels, microchannels, and other curved settings. Accelerating plasmonic beams (which are made of plasma oscillations instead of light) could potentially be used to transfer power from one area to another on a curved surface. The researchers plan to further explore these possibilities and others in the future.

    “We are now investigating the propagation of light within the thinnest curved membranes possible—soap bubbles of molecular thickness,” Patsyk said. “We are also studying linear and nonlinear wave phenomena, where the laser beam affects the thickness of the membrane and in return the membrane affects the light beam propagating within it.”

    See the full article here .

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    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

     
  • richardmitnick 9:32 am on July 31, 2017 Permalink | Reply
    Tags: "Bugs in the System", , Harvard University, , Microbiota, , Wendy Garrett,   

    From Harvard: Women in STEM – “Bugs in the System” Wendy Garrett 

    Harvard University
    Harvard University

    Harvard T.H. Chan School of Public Health

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    No image credit.

    7.31.17
    Nicole Davis

    Physician-scientist Wendy Garrett explores the multitude of microbes that live inside the human body, and how they can help fuel—or fend off—disease.

    From a microbial perspective, the human colon is a teeming metropolis, home to the most densely populated collection of microbes on the planet. Remarkably, these organisms are not only tolerated but also often required for normal body functioning—as much a part of human biology as our own cells.

    “We’re used to thinking about microbes as enemies—as major threats to our health—but most microbes don’t cause disease. They actually help us live better,” says Wendy Garrett, professor of immunology and infectious diseases at the Harvard T. H. Chan School of Public Health. “We are symbionts: human cells coexisting with bacterial cells, fungi, viruses, and parasites. We’re multispecies beings.”

    Garrett explores the vast community known as the microbiota, which is increasingly recognized for its central role in human health. Her laboratory has a particular focus on the gut, where more than 1,000 types of microbial habitués reside. Working with a team of postdoctoral scholars, graduate students, and other lab members, she seeks to understand how the microbiota contributes to major diseases of the gastrointestinal system, including colorectal cancer—the fourth-leading cause of death globally and second-leading cause of cancer death in the U.S.—and inflammatory bowel disease (IBD).

    Garrett is also intrigued by how gut microbes might shed light on cancer development and cancer treatments. Why do some tumors respond to certain cancer-fighting therapies—immunotherapy, for example—while others do not? With a deeper knowledge of the microbiota, it may become possible to manipulate microbes in ways that boost the effectiveness of cancer treatments and perhaps prevent the disease from arising in the first place.

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    Wendy Garrett, Professor of Immunology and Infectious Diseases

    Doctor-scientist

    Garrett’s fascination with science began in childhood, when she conducted improvised experiments in her parents’ basement—among other things, culturing various types of mold on bread—and later joining her elementary school electronics club. These early exposures made her not only a passionate mentor to young researchers inside and outside her lab but also deeply supportive of STEM (science, technology, engineering, and math) initiatives for grade-schoolers. She has also steeped her own two children in science, and her entire laboratory visits her kids’ elementary school to lead microbiology lessons. As Garrett sees it, “Everyone’s a scientist.”

    Garrett’s current study of microbes stems in part from her role as an attending physician specializing in gastrointestinal malignancies at the Dana-Farber Cancer Institute. She was influenced by a series of seminal discoveries in the 1980s and ’90s about the bacterium Helicobacter pylori. Those studies revealed it was H. pylori—not stress or spicy foods, as the conventional wisdom had it—that triggered stomach inflammation and ulcers, which in turn raise the risk of gastric cancer. When first proposed in the early 1980s, the bacterium-ulcer model was derided; today, it is the accepted paradigm.

    “Cancer is really complex, and microbes are complex too,” Garrett says. “But if we could work on both sides of the challenge simultaneously—the cancer and the microbes—we might find something new that can help treat or even prevent malignancy.”

    Her dual roles as a physician-scientist—“the broad, thoughtful process of medicine and the experimental, reductionist path in basic science”—feed each other, Garrett adds. In the hospital, she talks to colleagues about how the microbiota affects patient care and well-being; witnessing her patients’ struggles up close, meanwhile, spurs her to do the research that may someday ease such suffering.

    Microbial revival

    The microbiota (sometimes called the “microbiome,” although technically that term refers to the microbes’ aggregate genomes) may seem like a new concept, but scientists have been talking about and studying it for at least a century. In the early 1900s, Élie Metchnikoff, a Russian zoologist known for his Nobel Prize–winning work on the immune system, theorized that toxic bacteria in the gut caused aging and senility. He was particularly taken with the idea of replacing native gut microbes with “host-friendly” microbes, such as those found in yogurt, to promote health and longevity—work that presaged the now-booming field of probiotics.

    While the notion of “good bacteria” hearkens back to the days of Metchnikoff, Garrett’s work draws on technological capabilities that the 19th-century experimentalist could only dream of. Today’s tools for studying microbial communities—hundreds or thousands of species at once—include large-scale DNA sequencing, which has evolved rapidly over the last 20 years. Instead of culturing bacteria and other microbes in the laboratory to study them, scientists can now directly analyze their DNA, bypassing the need to precisely match microbes with their preferred growth conditions.

    Similar technological leaps have helped expand scientists’ view beyond microbial DNA to RNA, metabolites (by-products of the body’s metabolism), and other sources of biological information. “Now when we study the microbiota, there are many ‘omes’ beyond the conventional genomes that we can think about,” says Garrett, referring to such biological data sets as the metabolome (the small-molecule metabolic chemicals found in tissue), proteome (the complement of proteins expressed in an organism), exposome (all of an individual’s nongenetic exposures over a lifetime), and others.

    Gut signatures

    Harnessing this information could help scientists construct new models of how host cells and symbiont microbes communicate. Alongside the gut’s dense microbial community, for example, are patrols of immune cells perpetually on high alert against infection. When these cells and the defensive inflammation they trigger careen out of control, however, IBD can develop. Garrett’s laboratory seeks to pinpoint what provokes this extreme response: Is it driven by the immune system, the microbes, or a mix of both?

    In some IBD patients, the immune systems are altered in critical ways, and these differences affect key immune gatekeepers known as regulatory T cells. There are also notable differences in the types and number of bacteria that live in the guts of healthy individuals, compared with those suffering from IBD.

    “We thought about the bacteria that are decreased in people with IBD or increased in people without IBD, and that got us thinking about bacterial metabolism in the colon,” explains Garrett. “We had this idea that maybe short-chain fatty acids, which are an abundant bacterial metabolite in the colon, might play an important role.”

    These molecules have relatively compact chemical backbones, comprising just a handful of carbon atoms. Gut microbes make them by using building blocks from fiber-rich foods. Remarkably, when Garrett’s team fed short-chain fatty acids to mice, healthy or not, they found that the number of regulatory T cells rose. And in a mouse model of IBD, the treatment dramatically improved their disease. Garrett and her colleagues are now extending this line of research by exploring the biological mechanisms behind the therapeutic effect and extrapolating how these mechanisms might play out in humans.

    “Tasting” parasitic intruders

    The gastrointestinal tract is also home to parasites—both single-celled organisms and large, multicellular ones such as roundworms and other wormlike creatures. “One of the next frontiers of microbiota research is to better understand how the gut senses and determines whether a parasite is friend or foe, and how those differences contribute to health and disease,” says Garrett.

    In a paper published in Science in 2016, Garrett and her colleagues describe how specialized cells in the gut detect parasites. Known as tuft cells, for the clumps of hairlike projections at their tip, they can sample intestinal contents using a form of taste similar to the one taste buds use to signal whether foods are bitter, savory, or sweet. When tuft cells encounter parasites, the cells release a chemical that not only triggers the immune system but also orchestrates tuft cell proliferation, thereby expanding their own numbers in the gut. This in turn rallies the immune system, enabling it to fight off parasitic intruders.

    “It’s an elegant system, and one that can teach us a lot about diseases with a significant global impact—like giardiasis, roundworm, and hookworm,” says Garrett. “This will teach us how parasites influence the immune system, which has implications not only for how we fight parasitic diseases of the gut but also how we think about allergic and inflammatory diseases.” Research from other labs suggests that people with microbiota that harbor or have harbored parasites are less likely to suffer from IBD and other autoimmune diseases.

    Sticky business

    Although her laboratory studies a variety of microbes, Garrett has focused on one in particular: Fusobacterium nucleatum. About five years ago, she and her colleagues, including scientists at the Broad Institute and Dana-Farber Cancer Institute, discovered that these bacteria live inside colorectal tumors. “A subset of patients with colon cancer had large numbers of these bacteria in their tumors,” she says.

    Fusobacteria, which typically thrive in the mouth, are more than mere biological bystanders. In the gut, they appear to incite tumor growth, acting via the immune system itself. Garrett’s group found that the microbes recruit certain immune cells that, instead of rallying the immune system, actively suppress it, allowing colorectal tumors to grow unchecked.

    In the last few years, Garrett and her colleagues have delved more deeply into these subversive tactics through collaborations with Gilad Bachrach and Ofer Mandelboim at the Hebrew University of Jerusalem in Israel. In a paper published in Immunity in 2015, they revealed some of the key molecular players that inhibit the immune system. Last August, in a study published in Cell Host & Microbe, the team described how fusobacteria find their way to colon tumors—through a special sugar-binding protein that sits on the bacterial cell surface and enables the microbes to stick to the sugary coatings on colon cancer cells.

    “These bacteria have evolved a mechanism to avoid the immune system. If the bacteria are inside a cancer, the consequence is that it helps the cancer escape the immune system too,” says Garrett. “If we can find a way to block the sugar-binding proteins on these bacteria, then we may be able to prevent their role in tumor progression.”

    Such groundbreaking ideas have earned Garrett accolades from colleagues. “By deciphering the mechanistic bases of the interactions between the microbiota and the immune system, Dr. Garrett and her colleagues have revealed stunning new insights into the causes of inflammatory and neoplastic diseases,” says Matthew Waldor, the Edward H. Kass Professor of Medicine at Harvard Medical School. “She is one of the rare remaining ‘triple threats’: amazing clinician, teacher, and scientist.”

    Search for gold

    Colorectal cancer is squarely in the sights of medical research. Over the last four decades, timely screening beginning at age 50 has helped detect precancerous polyps (which can be removed) as well as early cancer (for which treatment is most effective). New therapies are also in the pipeline.

    But prevention—precisely targeted, powerful means to block tumors from growing in the first place, particularly in high-risk individuals—is equally urgent and equally promising, Garrett says. “We understand so much about the disease and its risk factors, both within the microbiota and within the host, that we may someday prevent colon cancer from ever developing.”

    Garrett’s lab has a Latin motto: Aurum ex Stercore. It means “to gold from dung,” a phrase that dates back to the classic challenge in medieval alchemy of transforming something seen as repugnantly useless into something inestimably precious. “Gold represents a scientific discovery that has the potential to help humanity,” Garrett says. “My sincere wish is to build a better system from a microbial perspective, so that we don’t even meet the eventuality of cancer.”

    See the full article here .

    Please help promote STEM in your local schools.

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    Harvard T.H. Chan School of Public Health traces its roots to public health activism at the beginning of the last century, a time of energetic social reform. From the start, faculty were expected to commit themselves to research as well as teaching. In 1946, no longer affiliated with the medical school, the School became an independent, degree-granting body.

    Today, the Harvard T.H. Chan School of Public Health brings together dedicated experts from many disciplines to educate new generations of global health leaders and produce powerful ideas that improve the lives and health of people everywhere.

    We work together as a community of leading scientists, educators, and students to take innovative ideas from the laboratory to people’s lives, not only making scientific breakthroughs, but also working to change individual behaviors, public policies, and health care practices.

    Harvard University campus
    Harvard is the oldest institution of higher education in the United States, established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. It was named after the College’s first benefactor, the young minister John Harvard of Charlestown, who upon his death in 1638 left his library and half his estate to the institution. A statue of John Harvard stands today in front of University Hall in Harvard Yard, and is perhaps the University’s best known landmark.

    Harvard University has 12 degree-granting Schools in addition to the Radcliffe Institute for Advanced Study. The University has grown from nine students with a single master to an enrollment of more than 20,000 degree candidates including undergraduate, graduate, and professional students. There are more than 360,000 living alumni in the U.S. and over 190 other countries.

     
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