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  • richardmitnick 10:59 am on September 8, 2020 Permalink | Reply
    Tags: "Grains of dust revise Solar System history", , Asteroids like Vesta formed in the inner Solar System are built of materials with a different array of chemical isotopes than those from asteroids which formed farther out in the Solar System., , , , Carbonaceous chondrite meteorites, , , Such meteorites are chips off asteroids that have been blasted into space by collisions only to eventually fall to Earth where they can be examined in laboratories., UC Davis   

    From UC Davis via COSMOS: “Grains of dust revise Solar System history” 

    UC Davis bloc

    From UC Davis

    via

    Cosmos Magazine bloc

    COSMOS

    8 September 2020
    Richard A Lovett

    Scientists study the chemical composition of meteorites.

    1
    Credit: Science Photo Library – andrzej/Getty Images.

    Asteroids that formed far out in the Solar System appear to contain dust grains that themselves condensed from the infant Solar System’s protoplanetary disc much closer to the Sun, scientists say.

    That means this dust was somehow transported from the inner reaches of the disc to its outer reaches, says Curtis Williams, a geochemist at the University of California, Davis. Once there, it mixed with material that condensed from that part of the disc to form larger objects that eventually became asteroids.

    In a study described in the journal PNAS, Williams and a team of US and Japanese researchers found these dust grains in a type of meteorite known as carbonaceous chondrites.

    Such meteorites are chips off asteroids that have been blasted into space by collisions, only to eventually fall to Earth, where they can be examined in laboratories.

    Previous studies had found that rocks from Earth and Mars, as well as asteroids like Vesta, which formed in the inner Solar System, are built of materials with a different array of chemical isotopes than those from asteroids known to have formed farther out in the Solar System.

    Based on that, scientists had assumed that inner Solar System dust – which is different from outer Solar System dust because it condensed in hotter regions closer to the Sun – did not mix with outer Solar System dust. Instead, they assumed, it remained relatively close to the Sun.

    The reason for this separation, they assumed, was the formation of the giant planet Jupiter, whose enormous gravity created a gap through which dust could not migrate. This, they assumed, divided the young Solar System into two distinct parts.

    In the new study, however, Williams’s team delved into 30 carbonaceous chondrites and looked at their individual components. “They have microcomponents, called inclusions,” Williams says.

    Looking carefully at isotopes in these sand-grain-sized inclusions, he says, his team found that some formed in the outer Solar System, but some must have formed closer to the Sun, then migrated outward before accreting into a larger body.

    Since Jupiter is believed to have already been present at the time these grains dispersed, Williams says, “that has big implications. Either Jupiter was not a complete barrier, or these particles somehow jumped over Jupiter and landed in the outer Solar System.”

    It’s an important finding partly because it will help planet-formation modellers better understand how dust grains migrate around a protoplanetary disk – including one in which giant planets are forming – before being incorporated into larger objects.

    But it will also help modellers figure out important aspects of conditions in these protoplanetary discs, including the viscosity and turbulence of their gas and dust.

    “That plays a role in how you build planets,” Williams says.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Davis Campus

    The University of California, Davis, is a major public research university located in Davis, California, just west of Sacramento. It encompasses 5,300 acres of land, making it the second largest UC campus in terms of land ownership, after UC Merced.

     
  • richardmitnick 2:29 pm on January 28, 2020 Permalink | Reply
    Tags: "UC Davis Releases 5 New Wine Grape Varieties", Food & Agriculture, Pierce’s disease also threatens wine grapes in the southeastern U.S., Pierce’s disease costs California grape growers more than $100 million a year., Pierce’s disease is caused by a bacterium spread by a group of insects called sharpshooters., Pierce’s disease occurs most often near rivers and creeks and around urban and rural landscaping where sharpshooter populations reside., UC Davis   

    From UC Davis: “UC Davis Releases 5 New Wine Grape Varieties” 

    UC Davis bloc

    From UC Davis

    December 18, 2019 [Just now in social media.]
    Amy Quinton

    Plants Are Resistant to Deadly Pierce’s Disease.

    1
    Paseante noir, is one of five new Pierce’s disease resistant grape varieties developed by Andrew Walker, geneticist and professor of viticulture and enology at UC Davis. It has characteristics similar to a zinfandel. (Dan Ng/UC Davis)

    2
    Ambulo blanc, one of two new white grape varieties, is similar to sauvignon blanc and has been tested in Sonoma, Temecula and Napa. Credit: (Dan Ng/UC Davis)

    For the first time since the 1980s, University of California, Davis, researchers have released new varieties of wine grapes. The five new varieties, three red and two white, are highly resistant to Pierce’s disease, which costs California grape growers more than $100 million a year. The new, traditionally bred varieties also produce high-quality fruit and wine.

    “People that have tasted the wine made from these varieties are extremely excited,” said Andrew Walker, geneticist and professor of viticulture and enology at UC Davis, who developed the new Pierce’s disease resistant varieties. “They are impressed that they’re resistant but also that they make good wine.”

    Pierce’s disease a growing threat

    Pierce’s disease is caused by a bacterium spread by a group of insects called sharpshooters. It causes grapevine leaves to yellow or “scorch” and drop from the vine. The grape clusters also dehydrate, and infected vines soon die. While the disease has been around since the beginning of wine grape production in California, concerns have escalated with the arrival of the nonnative glassy-winged sharpshooter, which has the potential to spread the disease more rapidly. Pierce’s disease occurs most often near rivers and creeks, and around urban and rural landscaping where sharpshooter populations reside.

    Pierce’s disease also threatens wine grapes in the southeastern U.S. Rising temperatures from climate change could increase the spread of the disease, which is thought to be limited by cold winters. Growers in the Southeast can usually only grow Pierce’s disease resistant varieties that don’t have the same wine quality as the European wine grape species, Vitis vinifera, which is typically grown in California.

    New varieties more sustainable

    To create the new varieties, Walker crossed a grapevine species from the southwestern U.S. and northern Mexico, Vitis arizonica, which carries a single dominant gene for resistance to Pierce’s disease and was used to cross back to Vitis vinifera over four to five generations. It’s taken about 20 years to develop the five patent-pending selections that are now being released.

    “These varieties will hopefully make viticulture much more sustainable and provide a high-quality wine that the industry will welcome,” said Walker. “So far there has not been tremendous interest in new wine grape varieties, but climate change may encourage growers to reconsider wine grape breeding as we work to address future climates and diseases.”

    Winemaker Adam Tolmach, owner of The Ojai Vineyard in Ojai, planted four of the new varieties as part of a 1.2-acre experimental field trial. The trial was on the same plot of land where Pierce’s disease wiped out his grapes in 1995. The vineyard then and now is organic, so spraying insecticides to fight the disease spread wasn’t an option.

    “I wasn’t interested in planting in that plot again until I heard about these new Pierce’s disease resistant grape varietals,” said Tolmach. “This year was the first harvest. We’ve just begun to evaluate the wine but I’m very encouraged.”

    3
    Errante noir, a new red grape variety, is most similar to a cabernet sauvignon. (Dan Ng/UC Davis)

    The five new varieties of wines were evaluated by sensory tasting panels. Tasters included leading industry winemakers and enologists in prominent wine-growing regions of California and Texas as well as regions in the southeastern U.S.

    “What I think is exciting is that they’re stand-alone varieties independent of whether they have Pierce’s disease resistance,” said Doug Fletcher, former vice president of winemaking for Terlato Family Wine Group.

    The three new red varieties are camminare noir, paseante noir and errante noir.

    Camminare noir has characteristics of both cabernet sauvignon and petite sirah. The selection has ranked highly at numerous tastings of fruit grown in both Napa and Davis. Tasting comments: dark-red purple color, bright red fruit, raspberry, cherry, ripe, tannic, elegant rather than dense. The variety is 50 percent petite sirah and 25 percent cabernet sauvignon.

    5
    Caminante blanc, a new white grape variety, has characteristics of both sauvignon blanc and chardonnay. (Dan Ng/UC Davis)

    Paseante noir is similar to zinfandel. It has also been ranked highly at tastings. Tasting comments: medium dark red with purple; berry pie, cassis, black olive, herbal, dried hay, coffee, vegetal like cabernet sauvignon, licorice, round, moderate tannins, soft finish. The variety is 50 percent zinfandel, 25 percent petite sirah and 12.5 percent cabernet sauvignon.

    Errante noir is a red wine grape most similar to a cabernet sauvignon and has great blending potential. Tasting comments: dark-red purple color; complex fruit with herbs and earth, plum, big wine, dense, rich middle, tannic yet balanced. The variety is 50 percent sylvaner and 12.5 percent each of cabernet sauvignon, carignane and chardonnay.

    The two new white grape varieties are ambulo blanc and caminante blanc.

    Ambulo blanc is similar to sauvignon blanc and has been tested in Temecula, Sonoma and along the Napa River. Tasting comments: light straw to clear color, citrus, lime, tropical, gooseberry, golden delicious apple flavors; bright fruit, slightly bitter, textured. The variety is 62.5 percent cabernet sauvignon, 12.5 percent carignane and 12.5 percent chardonnay.

    Caminante blanc has characteristics of sauvignon blanc and chardonnay. Wines have been made from Davis fruit and ranked well. Field trials are underway at Pierce’s disease hot spots in Ojai and Napa. Tasting comments: light straw-gold color, apple-melon, lychee, floral aromas, pineapple, green apple, juicy, harmonious, well-balanced. The variety is 62.5 percent cabernet sauvignon, 12.5 percent chardonnay and 12.5 percent carignane.

    These five varieties are ready for patenting and release. There will be limited amounts of plant material available for propagation in 2020 as only a few of the grape nurseries participated in a pre-release multiplication program. Much more will be available in 2021. The Pierce’s disease resistance breeding program continues, and more selections are approaching release.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Davis Campus

    The University of California, Davis, is a major public research university located in Davis, California, just west of Sacramento. It encompasses 5,300 acres of land, making it the second largest UC campus in terms of land ownership, after UC Merced.

     
  • richardmitnick 3:54 pm on January 17, 2020 Permalink | Reply
    Tags: "Taking the Temperature of Dark Matter", , , , , UC Davis   

    From UC Davis: “Taking the Temperature of Dark Matter” 

    UC Davis bloc

    From UC Davis

    January 15, 2020
    Andy Fell

    1
    Gravitational Lensing. This image from the Hubble Space Telescope shows lensing of distant galaxies by gravity. UC Davis astronomers are using this phenomenon to learn more about the properties of dark matter.

    Warm, cold, just right? Physicists at the University of California, Davis, are taking the temperature of dark matter, the mysterious substance that makes up about a quarter of our universe.

    We have very little idea of what dark matter is, and physicists have yet to detect a dark matter particle. But we do know that the gravity of clumps of dark matter can distort light from distant objects. Chris Fassnacht, a physics professor at UC Davis, and colleagues are using this distortion, called gravitational lensing, to learn more about the properties of dark matter.

    The standard model for dark matter is that it is ”cold,” meaning that the particles move slowly compared to the speed of light, Fassnacht said.

    Lamda Cold Dark Matter Accerated Expansion of The universe http scinotions.com the-cosmic-inflation-suggests-the-existence-of-parallel-universes
    Alex Mittelmann, Coldcreation

    This is also tied to the mass of dark matter particles. The lower the mass of the particle, the “warmer” it is and the faster it will move.

    The model of cold (more massive) dark matter holds at very large scales, Fassnacht said, but doesn’t work so well on the scale of individual galaxies. That’s led to other models including “warm” dark matter with lighter, faster-moving particles. “Hot” dark matter with particles moving close to the speed of light has been ruled out by observations.

    A limit on the mass of dark matter

    Former UC Davis graduate student Jen-Wei Hsueh, Fassnacht and colleagues used gravitational lensing to put a limit on the warmth and therefore the mass of dark matter. They measured the brightness of seven distant gravitationally lensed quasars to look for changes caused by additional intervening blobs of dark matter and used these results to measure the size of these dark matter lenses.

    If dark matter particles are lighter, warmer and more rapidly moving, then they will not form structures below a certain size, Fassnacht said.

    “Below a certain size, they would just get smeared out,” he said.

    The results put a lower limit on the mass of a potential dark matter particle while not ruling out cold dark matter, he said. The team’s results represent a major improvement over a previous analysis, from 2002, and are comparable to recent results from a team at UCLA.

    Fassnacht hopes to continue adding lensed objects to the survey to improve the statistical accuracy.

    “We need to look at about 50 objects to get a good constraint on how warm dark matter can be,” he said.

    A paper describing the work is published in the Monthly Notices of the Royal Astronomical Society. Additional co-authors are: W. Enzi, S. Vegetti and G. Despali, Max Planck Institute for Astrophysics, Garching, Germany; M.W. Auger, Institute of Astronomy, University of Cambridge, U.K.; L.V.E. Koopmans, Kapteyn Astronomical Institute, University of Groningen, The Netherlands; and J.P. McKean, Netherlands Institute for Radio Astronomy. The work was supported by the National Science Foundation, the Netherlands Organization for Scientific Research and the Chinese Academy of Sciences.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Davis Campus

    The University of California, Davis, is a major public research university located in Davis, California, just west of Sacramento. It encompasses 5,300 acres of land, making it the second largest UC campus in terms of land ownership, after UC Merced.

     
  • richardmitnick 12:09 pm on January 11, 2020 Permalink | Reply
    Tags: "Satellite constellations harvest energy for near-total global coverage", A four-satellite constellation to maintain nearly continuous 24/7 coverage of almost every point on Earth., , , , , , , The Aerospace Corporation, The company’s expertise in cutting-edge astrophysics operational logistics and simulations., UC Davis   

    From Cornell Chronicle: “Satellite constellations harvest energy for near-total global coverage” 

    From Cornell Chronicle

    January 10, 2020
    David Nutt

    1
    Patrick Reed collaborated with researchers from The Aerospace Corporation to determine the right combination of factors that would enable a four-satellite constellation to maintain nearly continuous 24/7 coverage of almost every point on Earth. The Aerospace Corporation.

    Think of it as a celestial parlor game: What is the minimum number of satellites needed to see every point on Earth? And how might those satellites stay in orbit and maintain continuous 24/7 coverage while contending with Earth’s gravity field, its lumpy mass, the pull of the sun and moon, and pressure from solar radiation?

    In the mid-1980s, researcher John E. Draim proposed what is generally considered to be the ideal solution: a four-satellite constellation. However, the amount of propellant needed to keep the satellites in place, and the ensuing cost, made the configuration unfeasible.

    Now, a National Science Foundation-sponsored collaboration led by Patrick Reed, the Joseph C. Ford Professor of Engineering, has discovered the right combination of factors to make a four-satellite constellation possible, which could drive advances in telecommunication, navigation and remote sensing.

    And in an ingenious twist, the researchers accomplished this by making the forces that ordinarily degrade satellites instead work in their favor.

    “One of the interesting questions we had was, can we actually transform those forces? Instead of degrading the system, can we actually flip it such that the constellation is harvesting energy from those forces and using them to actively control itself?” Reed said.

    Their paper, Low Cost Satellite Constellations for Nearly Continuous Global Coverage, published Jan. 10 in Nature Communications.

    The AI-based evolutionary computing search tools that Reed has developed are ideally suited for navigating the numerous complications of satellite placement and management.

    For this project, Reed collaborated with researchers from The Aerospace Corporation, combining his algorithmic know-how with the company’s expertise in cutting-edge astrophysics, operational logistics and simulations.

    In order to sift through the hundreds of thousands of possible orbits and combinations of perturbations, the team used the Blue Waters supercomputer at University of Illinois, Urbana-Champaign.

    NCSA U Illinois Urbana-Champaign Blue Waters Cray Linux XE/XK hybrid machine supercomputer

    Blue Waters compressed 300 or 400 years’ worth of computational exploration into the equivalent of roughly a month of actual computing, Reed said.

    They winnowed their constellation designs to two models that could orbit for either a 24- or 48-hour period and achieve continuous coverage over 86% and 95% of the globe, respectively. While 100% performance coverage would be ideal in theory, the researchers found that sacrificing only 5%-14% created greater gains in terms of harvesting energy from the same gravitational and solar radiation forces that would normally make a satellite constellation short lived and difficult to control.

    The tradeoff is worth it, Reed said, especially since satellite operators could control where the gaps in coverage would occur. Outages in these low-priority regions would last approximately 80 minutes a day, at most, in the worst-case scenario.

    “This is one of those things where the pursuit of perfection actually could stymie the innovation,” Reed said. “And you’re not really giving up a dramatic amount. There might be missions where you absolutely need coverage of everywhere on Earth, and in those cases, you would just have to use more satellites or networked sensors or hybrid platforms.”

    Using this type of passive control could potentially extend a constellation’s lifespan from five years to 15 years. These satellites would require less propellant and would float at higher elevations, removing them from the risky high-traffic zone of low Earth orbit. But perhaps the biggest selling point is the low cost. Commercial interests or countries without the financial resources to launch a large constellation of satellites could attain near-continuous global coverage very economically, with reduced long-term technical overhead.

    “Even one satellite can cost hundreds of millions or billions of dollars, depending on what sensors are on it and what its purpose is. So having a new platform that you can use across the existing and emerging missions is pretty neat,” Reed said. “There’s a lot of potential for remote sensing, telecommunication, navigation, high-bandwidth sensing and feedback around the space, and that’s evolving very, very quickly. There’s likely all sorts of applications that might benefit from a long-lived, self-adapting satellite constellation with near global coverage.”

    The paper’s lead author is Lake Singh with The Aerospace Corporation. Researchers from the University of California, Davis, also contributed.

    “We leveraged Aerospace’s constellation design expertise with Cornell’s leadership in intelligent search analytics and discovered an operationally feasible alternative to the Draim constellation design,” said Singh, systems director for The Aerospace Corporation’s Future Architectures department. “These constellation designs may provide substantive advantages to mission planners for concepts out at geostationary orbits and beyond.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Once called “the first American university” by educational historian Frederick Rudolph, Cornell University represents a distinctive mix of eminent scholarship and democratic ideals. Adding practical subjects to the classics and admitting qualified students regardless of nationality, race, social circumstance, gender, or religion was quite a departure when Cornell was founded in 1865.

    Today’s Cornell reflects this heritage of egalitarian excellence. It is home to the nation’s first colleges devoted to hotel administration, industrial and labor relations, and veterinary medicine. Both a private university and the land-grant institution of New York State, Cornell University is the most educationally diverse member of the Ivy League.

    On the Ithaca campus alone nearly 20,000 students representing every state and 120 countries choose from among 4,000 courses in 11 undergraduate, graduate, and professional schools. Many undergraduates participate in a wide range of interdisciplinary programs, play meaningful roles in original research, and study in Cornell programs in Washington, New York City, and the world over.

     
  • richardmitnick 12:26 pm on October 12, 2019 Permalink | Reply
    Tags: "Does Foamy Spacetime Answer the Problem of Dark Energy?", , , , , UC Davis   

    From UC Davis: “Does Foamy Spacetime Answer the Problem of Dark Energy?” 

    UC Davis bloc

    From UC Davis

    October 11th, 2019
    Andy Fell

    What does space look like at a really, really small scale? Answering that question could resolve one of the most difficult problems in modern physics, the huge mismatch between Einstein’s General Relativity, quantum theory and the measured acceleration of the expansion of the universe.

    1
    Physicists have struggled to reconcile predictions of the cosmological constant (the energy of empty space) with the observed dark energy driving the galaxies apart. If spacetime is “foamy” at a tiny scale, it could solve the problem. (Hubble Space Telescope image)

    NASA/ESA Hubble Telescope

    Cosmologists have known for about 20 years that the universe is not just expanding, but that the expansion is speeding up. To explain this cosmic acceleration, theoretical physicists invoked “dark energy,” a force that emerges from quantum fluctuations of the vacuum of space and pushes the galaxies apart.

    Einstein’s theory of general relativity includes a value for the vacuum energy of space, the cosmological constant. When Einstein proposed general relativity in 1915, the universe was thought to be static. So he included the cosmological constant in his equations to counter gravity and prevent the universe from collapsing on itself. In the 1930s, astronomers found that the universe was expanding from the Big Bang and Einstein abandoned the idea as a mistake.

    The discovery of cosmic acceleration and dark energy caused theorists to take another look at the cosmological constant. But there is a problem.

    “We don’t really know how to calculate the cosmological constant,” said Steve Carlip, distinguished professor of physics at UC Davis. “Methods that work in other contexts give an answer 60 to 120 orders of magnitude larger than the observed dark energy, which is pretty bad.”

    Foamy spacetime at a very small scale

    Physicists have been tinkering with ways to cover this gap, including making tweaks to general relativity or invoking multiple universes with different cosmological constants. In a new paper published in Physical Review Letters, Carlip proposes a new direction that sees spacetime at a very small scale as a complex foamy structure.

    The idea of spacetime foam dates back to the 1950s and cosmologist John Wheeler at Princeton University. Wheeler proposed that at the Planck scale – distances of 10 to the negative 35 meters, 100 million trillion times smaller than a proton – space would not be continuous, but foamy.

    If you look at the ocean from a great height, Carlip said, it looks smooth. Get closer and you can see swells and waves. Closer still and you can see the foam and spray among those waves.

    In the same way, the small-scale structure of spacetime would become apparent as you get close to it. Wheeler did not have the mathematical tools to build a model of foamy spacetime but these now exist.

    Carlip’s new approach is to accept that the value of the cosmological constant really is huge as calculated, but that it does not necessarily have the same effect everywhere in the universe. In a model of spacetime made of tiny bubbles, the cosmological constant could cause opposite effects, acceleration or deceleration, in neighboring bubbles. These would tend to cancel each other out leaving only the small, residual effect that we see as dark energy.

    “If you look at space at a fixed time and choose a complex structure, the cosmological constant is almost invisible,” Carlip said.
    The new theory is a “direction to explore” not a complete solution, Carlip said. While it works at a point in time, it’s not clear how it would evolve other time. It’s also not clear how scientists could test the idea experimentally. But it could spur some new developments.

    “The hope is this may give us some hints of where to go in the theory of quantum gravity,” Carlip said.

    See the full article here .
    See also from Physics here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Davis Campus

    The University of California, Davis, is a major public research university located in Davis, California, just west of Sacramento. It encompasses 5,300 acres of land, making it the second largest UC campus in terms of land ownership, after UC Merced.

     
  • richardmitnick 12:29 pm on September 25, 2019 Permalink | Reply
    Tags: , , , Geologists can measure specific isotopes in igneous rocks to learn more about the origin and evolution of the Earth., , The mantle is a layer of rock stretching 2900 kilometers (1802 miles) down inside the Earth., The specific giant rock regions have existed for 4.5 billion years since Earth’s beginning., There are gigantic masses in Earth’s mantle untouched for more than 4 billion years., These distinct regions may have been formed from an ancient magma ocean that solidified during the beginning of Earth’s formation and may have survived the massive Moon-creating impact., Two solid continents were found in the deep mantle. One solid rock body is under Africa and the other is under the Pacific Ocean., UC Davis   

    From UC Davis via AGU GeoSpace blog: “New study suggests gigantic masses in Earth’s mantle untouched for more than 4 billion years” 

    UC Davis bloc

    From UC Davis

    via


    AGU GeoSpace blog

    18 September 2019
    By Abigail Eisenstadt

    Ancient, distinct, continent-sized regions of rocks, isolated since before the collision that created the Moon 4.5 billion years ago, exist hundreds of miles below the Earth’s crust, offering a window into the building blocks of our planet, according to new research.

    The new study in the AGU Journal Geochemistry, Geophysics, Geosystems used models to trace the location and origin of volcanic rock samples found throughout the world back to two solid continents in the deep mantle. The new research suggests the specific giant rock regions have existed for 4.5 billion years, since Earth’s beginning.

    1
    This image shows the divisions between Earth’s layers. The ancient, continent-sized rock regions encircle the liquid outer core. Credit: Lawrence Livermore National Laboratory

    Previously, scientists theorized that separated continents in the deep mantle came from subducted oceanic plates. But the new study indicates these distinct regions may have been formed from an ancient magma ocean that solidified during the beginning of Earth’s formation and may have survived the massive Moon-creating impact.

    Determining the masses’ origin reveals more details about their evolution and composition, as well as clues about primordial Earth’s history in the early Solar System, according to the study’s authors.

    It’s amazing that these regions have survived most of Earth’s volcanic history relatively untouched, said Curtis Williams, a geologist at the University of California, Davis, in Davis, California and lead author of the study.

    Looking inward

    The mantle is a layer of rock, stretching 2,900 kilometers (1,802 miles) down inside the Earth. Earth’s molten, liquid, metallic core lies beneath the mantle. The core-mantle boundary is where the solid mantle meets the metallic liquid core.

    Scientists knew from past seismic imaging studies that two individual rock bodies existed near the core-mantle boundary. One solid rock body is under Africa and the other is under the Pacific Ocean.

    Seismic waves, the vibrations produced by earthquakes, move differently through these masses than the rest of the mantle, suggesting they have distinct physical properties from the surrounding mantle. But geologists couldn’t determine whether seismic waves moved differently through the core-mantle continents because of differences in their temperature, mineral composition or density, or some combination of these properties. That meant they could only hypothesize about the separate rocky masses’ origin and history.

    “We had all of these geochemical measurements from Earth’s surface, but we didn’t know how to relate these geochemical measurements to regions of Earth’s interior. We had all of these geophysical images of the Earth’s interior, but we didn’t know how to relate that to the geochemistry at Earth’s surface,” Williams said.

    Primitive material and plumes

    Williams and his colleagues wanted to determine the distinct masses’ origin and evolution to learn more about Earth’s composition and past. To do this, they needed to be able to identify samples at Earth’s surface with higher concentrations of primitive material and then trace those samples back to their origins.

    Scientists often take rock samples from volcanic regions like Hawaii and Iceland, where deep mantle plumes, or columns of extremely hot rock, rise from the areas near the core, melt in the shallow mantle and emerge far from tectonic fault lines. These samples are made of igneous rock created from cooling lava. The study’s authors used an existing database of samples and also collected new samples from volcanically active areas like the Balleny Islands in Antarctica.

    Geologists can measure specific isotopes in igneous rocks to learn more about the origin and evolution of the Earth. Some isotopes, like Helium-3, are primordial, meaning they were created during the Big Bang. Rocks closer to Earth’s crust have less of the isotope than rocks deeper underground that were never exposed to air. Samples with more Helium-3 are thought to come from more primitive rocks in the mantle.

    The researchers found some of the samples they studied had more Helium-3, indicating they may have come from primitive rocks deep in the Earth’s mantle.

    The researchers then used a new model to trace how these primitive samples could have gotten to the Earth’s surface from the mantle. Geological models assume plumes rise vertically from deep within the mantle to the Earth’s surface. But plumes can move off course, deflected, due to various reasons. The new model took into account this plume deflection, allowing the study’s authors to trace the samples back to the two giant masses near the core-mantle boundary.

    The combination of the isotope information and the new model allowed the researchers to determine the composition of the two giant masses and theorize how they may have formed.

    Understanding the composition of specific rock masses near the core-mantle boundary helps geologists conceptualize ancient Earth-shaping processes that led to the modern-day mantle, according to the study’s authors.

    “It’s a more robust framework to try and answer these questions in terms of not making these assumptions of vertically rising material but rather to take into account how much deflection these plumes have seen,” Williams said.

    See the full article here .

     
  • richardmitnick 3:48 pm on June 10, 2019 Permalink | Reply
    Tags: An alternative to the WIMP model of dark matter calls for a form of “dark electromagnetism” including “dark photons” and other particles, , , , , UC Davis   

    From UC Davis: “A New Candidate for Dark Matter and a Way to Detect It” 

    UC Davis bloc

    From UC Davis

    June 10, 2019
    Andy Fell

    1
    A simulation of the large-scale structure of the universe with filaments of dark matter in blue and places of galaxy formation in yellow. Dark matter cannot yet be detected directly. UC Davis physicists have proposed a new model to explain it. (Image: Zarija Lukic/Lawrence Berkeley National Laboratory)

    Two theoretical physicists at the University of California, Davis, have a new candidate for dark matter, and a possible way to detect it. They presented their work June 6 at the Planck 2019 conference in Granada, Spain, and it has been submitted for publication.

    Dark matter is thought to make up just over a quarter of our universe, with most of the rest being even-more mysterious dark energy. It cannot be seen directly, but dark matter’s presence can be detected because its gravity determines the shape of distant galaxies and other objects.

    Many physicists believe that dark matter is made up of some particle yet to be discovered. For some time, the favorite candidate has been the weakly interacting massive particle or WIMP. But despite years of effort, WIMPs have so far not shown up in experiments designed to detect them.

    “We still don’t know what dark matter is,” said John Terning, professor of physics at UC Davis and co-author on the paper. “The primary candidate for a long time was the WIMP, but it looks like that’s almost completely ruled out.”

    An alternative to the WIMP model of dark matter calls for a form of “dark electromagnetism” including “dark photons” and other particles. Dark photons would have some weak coupling with “regular” photons.

    In their new paper, Terning and postdoctoral researcher Christopher Verhaaren add a twist to this idea: a dark magnetic “monopole” that would interact with the dark photon.

    In the macroscopic world, magnets always have two poles, north and south. A monopole is a particle that acts like one end of a magnet. Monopoles are predicted by quantum theory but have never been observed in an experiment. The scientists suggest that dark monopoles would interact with dark photons and dark electrons in the same way that theory predicts electrons and photons interact with monopoles.

    And that implies a way to detect these dark particles. The physicist Paul Dirac predicted that an electron moving in a circle near a monopole would pick up a change of phase in its wave function. Because electrons exist as both particles and waves in quantum theory, the same electron could pass on either side of the monopole and as a result be slightly out of phase on the other side.

    This interference pattern, called the Aharonov-Bohm effect, means that an electron passing around a magnetic field is influenced by it, even if it does not pass through the field itself.

    Terning and Verhaaren argue that you could detect a dark monopole because of the way it shifts the phase of electrons as they pass by.

    “This is a new type of dark matter but it comes with a new way to look for it as well,” Terning said.

    Electron beams are relatively easy to come by: Electron microscopes were used to demonstrate the Aharonov-Bohm effect in the 1960s, and electron beam technology has improved with time, Terning noted.

    Theoretically, dark matter particles are streaming through us all the time. To be detectable in Terning and Verhaaren’s model, the monopoles would have to be excited by the sun. Then they would take about a month to reach Earth, traveling at about a thousandth of the speed of light.

    On the other hand, the predicted phase shift is extremely small — smaller than that needed to detect gravity waves, for example. However, Terning noted that when the LIGO gravity wave experiment was first proposed, the technology to make it work did not exist — instead, technology caught up over time.

    The work was supported by a grant from the U.S. Department of Energy.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Davis Campus

    The University of California, Davis, is a major public research university located in Davis, California, just west of Sacramento. It encompasses 5,300 acres of land, making it the second largest UC campus in terms of land ownership, after UC Merced.

     
  • richardmitnick 1:46 pm on January 20, 2019 Permalink | Reply
    Tags: , , Developing New Technologies to Extend Care to All Families Affected by Autism Spectrum Disorder, , THE BIG IDEA, UC Davis   

    From UC Davis: “Developing New Technologies to Extend Care to All Families Affected by Autism Spectrum Disorder” 

    UC Davis bloc

    From UC Davis

    January 14, 2019
    Katherine Lee

    UC Davis Has the Big Idea to Make It Happen

    The prevalence of Autism Spectrum Disorder (ASD) has almost tripled since 2000, affecting one in 59 children identified in the U.S., according to the Centers for Disease Control and Prevention (CDC).

    1

    “Everyone knows someone affected by autism. It’s time for us to take responsibility for the growing number of families in need of quality care,” said Leonard Abbeduto, director of the UC Davis Medical Investigation of Neurodevelopmental Disorders (MIND) Institute.

    The MIND Institute, which recently celebrated its 20th anniversary, was founded by families for families to advance scientific discovery and improve access to interdisciplinary, cutting-edge care. The Institute’s mission is “to use the best science we can to help as many families as we can.”

    Although ASD is a lifelong condition, effective treatments can reduce the disabilities associated with ASD and lead to happier, more fulfilling lives for families and individuals, but these treatments must be made more widely available. Currently, gaps in access to providers and affordable care make it especially hard for families who come from under-resourced populations or rural areas. Moreover, gaps in care delay early identification and intervention, affecting developmental outcomes.

    “Families in rural areas and other underserved communities may not be able to see experts without traveling long distances, which creates a financial burden and can delay treatment,” explained Abbeduto, who is also the champion of the Autism, Community and Technology Big Idea. “Technology can be used to overcome such barriers and get help to families in need everywhere.”

    3
    This Big Idea will harness the university’s unique strengths in health, neuroscience, engineering, education, community engagement, and social sciences, involving a variety of disciplines and perspectives to find innovative solutions for ASD.

    UC Davis’ Big Ideas are forward-thinking, interdisciplinary programs and projects that will build upon the strengths of the university to positively impact the world for generations to come. Researchers, scientists, clinicians and others are working on innovative and ambitious initiatives in the field of health, sustainability and more to solve both California’s and the world’s most pressing problems.

    The Autism, Community and Technology Big Idea will pioneer a first-of-its-kind lifespan approach for everyone living with autism. By building partnerships with communities, driving innovation in affordable and accessible technologies, and training doctors, nurses, teachers, employers, and family members, UC Davis will create new ways of advancing science and helping people with autism.

    “Every field of study will be relevant to adding its expertise and creativity to the solutions being proposed by this idea,” added Abbeduto. “However, without donor support, we won’t be able to help families in the way they deserve.”

    UC Davis poised to address urgent needs

    Home to more than 50 faculty and staff across five UC Davis schools and colleges, the MIND Institute will be a hub for the Big Idea, bringing together experts from various disciplines, as well as community groups, businesses, and families, to address autism on a grand scale. This expert knowledge will then be used to train doctors, nurses, teachers, employers and community leaders throughout the country. Such partnerships will address the needs of underserved populations and the unique challenges they face, using innovative technologies and solutions to help individuals living with autism and their families across communities.

    One such partner is Sergio Aguilar-Gaxiola, director of the UC Davis Center for Reducing Health Disparities. For more than 10 years, he has worked on projects with the MIND Institute to improve access to and utilization of services for families affected by autism, fragile X syndrome and other developmental disabilities.

    “When there is an urgent need such as this, we need big ideas to make real progress in advancing solutions,” Aguilar-Gaxiola said.

    Aguilar-Gaxiola and his team serve Solano County and other areas in California and focus on Latino, Filipino, LGBTQ and other diverse families as well as those who are low income or for whom English is not their first language. Children in these populations tend to be diagnosed with autism later than urban or white families – leading to delayed treatment and worse outcomes over time.

    “Some families live two to three hours away from providers, with more than one child with autism at home, so it is critically important for UC Davis to reach them where they are,” Aguilar-Gaxiola said.

    Telemedicine expands access to care

    Telehealth, which is remote access to health services and provider care, makes it possible for UC Davis to care for families affected by autism and other ASD conditions no matter where they live. The face-to-face interaction in their own home through video conferencing, and the use of other technology, allow parents to affordably receive direct feedback and input on how to improve interactions and build important skills in their child.

    The use of telemedicine more broadly and effectively can improve ASD screening and offer treatments in a variety of spoken languages and to families in all areas across California and the country.

    4
    Many children with ASD have challenging behaviors or problems with the change of routine associated with travel. Technology allows these families to overcome this access barrier, bringing care into their own home.

    Abbeduto recalls several patient families who were empowered through telemedicine. During a three- to four-month video conference training series with team members at the MIND Institute, these families learned how to become their child’s language therapist and were empowered to contribute to their child’s care. They were given strategies to support their child’s language development and to reduce the kinds of behaviors that impede social interaction.

    “Originally, family members were skeptical that they would be able to engage their child in play for longer periods of time by themselves,” Abbeduto said. “But at their exit interviews, without exception they each talked about how close they felt to their child and the unexpected positive changes in their life.”

    He concluded, “This kind of knowledge helps parents and caregivers overcome the need to depend on someone else to help their family. It allows them to feel more connected and competent and have more impact on their children.”

    Fostering independence and opportunity

    As part of the Big Idea, the MIND Institute is also developing interventions for adolescents and adults, a subgroup of individuals living with ASD who often experience a sudden lack of services after high school.

    Technology will allow interventions from the MIND Institute to better address the needs of these individuals. Virtual reality, apps, artificial intelligence and facial recognition software will be further developed and tested to support positive behaviors in communication and social skills needed for daily life.

    “We can use advances in technology to continue to monitor and support individuals living with autism so they can have fulfilling jobs and take part in a wider range of social activities throughout their lifespan,” explains Abbeduto.

    Furthermore, virtual support groups could connect individuals with autism or their families to additional social skills workshops, helping them move to independence and easing some of the burden on caregivers. Smart homes, for example, could be used to provide prompts for when it’s time to take medication or a bath, and give cues for getting ready for work or making a meal. Autism experts partnering with engineers could also utilize robotics to realize new ways of providing therapies and medications.

    The vision of this Big Idea will extend the reach of this technology, employing it in communities where experts in autism or specialized services are limited or non-existent. Through virtual conferences or workshops, UC Davis will be able to train the next generation of providers, teachers and administrators. This will empower and promote positive change at the individual level and create opportunities at a systems level.

    “Through this Big Idea, and with the help of donors, we will be able to create technologies that will take the expertise of the MIND Institute and extend its reach all over the world,” said Abbeduto. “It has the ability to make a positive impact on families everywhere.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Davis Campus

    The University of California, Davis, is a major public research university located in Davis, California, just west of Sacramento. It encompasses 5,300 acres of land, making it the second largest UC campus in terms of land ownership, after UC Merced.

     
  • richardmitnick 1:17 pm on January 20, 2019 Permalink | Reply
    Tags: , , , , Mantle Neon Illuminates Earth’s Formation, Neon is actually a stand-in for where gases such as water carbon dioxide and nitrogen came from, Neon keeps a memory of where it came from even after four and a half billion years, UC Davis   

    From UC Davis: “Mantle Neon Illuminates Earth’s Formation” 

    UC Davis bloc

    From UC Davis

    December 5, 2018
    Andy Fell
    530-752-4533
    ahfell@ucdavis.edu

    1
    Artist’s impression of a young star surrounded by a protoplanetary disk in which planets are forming. Based on measures of neon isotopes, UC Davis researchers conclude that the Earth formed relatively quickly from this cloud of dust and gas, collecting water, carbon and nitrogen in the deep Earth. (European Southern Observatory)

    The Earth formed relatively quickly from the cloud of dust and gas around the sun, trapping water and gases in the planet’s mantle, according to research published Dec. 5 in the journal Nature. Apart from settling Earth’s origins, the work could help in identifying extrasolar systems that could support habitable planets.

    Drawing on data from the depths of the Earth to deep space, University of California, Davis, Professor Sujoy Mukhopadhyay and postdoctoral researcher Curtis Williams used neon isotopes to show how the planet formed.

    “We’re trying to understand where and how the neon in Earth’s mantle was acquired, which tells us how fast the planet formed and in what conditions,” Williams said.

    Neon is actually a stand-in for where gases such as water, carbon dioxide and nitrogen came from, Williams said. Unlike these compounds that are essential for life, neon is an inert noble gas, and it isn’t influenced by chemical and biological processes.

    “So neon keeps a memory of where it came from even after four and a half billion years,” Mukhopadhyay said.

    There are three competing ideas about how the Earth formed from a protoplanetary disk of dust and gas over 4 billion years ago and how water and other gases were delivered to the growing Earth. In the first, the planet grew relatively quickly over 2 to 5 million years and captured gas from the nebula, the swirling cloud of dust and gas surrounding the young sun. The second theory suggests dust particles formed and were irradiated by the sun for some time before condensing into miniature objects called planetesimals that were subsequently delivered to the growing planet. In the third option, the Earth formed relatively slowly, and gases were delivered by carbonaceous chondrite meteorites that are rich in water, carbon and nitrogen.

    These different models have consequences for what the early Earth was like, Mukhopadhyay said. If the Earth formed quickly out of the solar nebula, it would have had a lot of hydrogen gas at or near the surface. But if the Earth formed from carbonaceous chondrites, its hydrogen would have come in the more oxidized form, water.

    Neon from ocean floor to deep space

    To figure out which of the three competing ideas on planet formation and delivery of gases was correct, Williams and Mukhopadhyay accurately measured the ratios of neon isotopes that were trapped in the Earth’s mantle when the planet formed. Neon has three isotopes, neon-20, 21 and 22. All three are stable and nonradioactive, but neon-21 is formed by radioactive decay of uranium. So the amounts of neon-20 and 22 in the Earth have been stable since the planet formed and will remain so forever, but neon-21 slowly accumulates over time. The three scenarios for Earth’s formation are predicted to have different ratios of neon-20 to neon-22.

    The closest they could get to the mantle was to look at rocks called pillow basalts on the ocean floor. These glassy rocks are the remains of flows from deep in the Earth that spilled out and cooled in the ocean, later to be collected by a drilling expedition led by the University of Rhode Island, which makes its collection available to other scientists.

    The gases are found in tiny bubbles within the basalt. Using a press, Williams cracked basalt chips in a sealed chamber, allowing the gases to flow into a sensitive mass spectrometer.

    Now for the space part. Previous researchers established the neon isotope ratio for the “solar nebula” (early rapid formation) model with data from the Genesis mission, which captured particles of the solar wind. Data for the “irradiated particles” model came from analyses of lunar soils and of meteorites. Finally, carbonaceous chondrite meteorites provided data for the “late accretion” model.

    Minimum size for a habitable planet

    The isotope ratios they found were well above those for the “irradiated particles” or “late accretion” models, Williams said, and support rapid early formation.

    “This is a clear indication that there is nebular neon in the deep mantle,” Williams said.

    Neon, remember, is a marker for those other volatile compounds. Hydrogen, water, carbon dioxide and nitrogen would have been condensing into the Earth at the same time — all ingredients that, as far as we know, go into making up a habitable planet.

    The results imply that to absorb these vital compounds, a planet must reach a certain size — the size of Mars or a little larger — before the solar nebula dissipates. Observations of other solar systems show that this takes about 2 to 3 million years, Williams said.

    Does the same process happen around other stars? Observations from the Atacama Large Millimeter Array, or ALMA, observatory in Chile suggest that it does, the researchers said.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    ALMA uses an array of 66 radiotelescopes working as a single instrument to image dust and gas in the universe. It can see the planet-forming disks of dust and gas around some nearby stars. In some cases, there are dark bands in those disks where dust has been depleted.

    “There are a couple of ways dust could be depleted from the disk, and one of them is that they are forming planets,” Williams said.

    “We can observe planet formation in a gas disk in other solar systems, and there is a similar record of our own solar system preserved in Earth’s interior,” Mukhopadhyay said. “This might be a common way for planets to form elsewhere.”

    The work was funded by the National Science Foundation.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Davis Campus

    The University of California, Davis, is a major public research university located in Davis, California, just west of Sacramento. It encompasses 5,300 acres of land, making it the second largest UC campus in terms of land ownership, after UC Merced.

     
  • richardmitnick 12:03 pm on December 26, 2018 Permalink | Reply
    Tags: , Fruit bats in Sierra Leone, Marburg virus in Sierra Leone, , UC Davis   

    From UC Davis: “Deadly Marburg Virus Found in Sierra Leone Bats” 

    UC Davis bloc

    From UC Davis

    December 20, 2018
    Kat Kerlin

    1
    Scientists detected Marburg virus in five Egyptian fruit bats, like this one, in Sierra Leone. (Getty)

    Scientists have discovered Marburg virus in fruit bats in Sierra Leone. This is the first time the deadly virus has been found in West Africa. Five Egyptian rousette fruit bats tested positive for active Marburg virus infection. Scientists caught the bats separately in three health districts: Moyamba, Koinadugu and Kono.

    The virus was found in advance of any reported cases of illness in people in Sierra Leone, and there remain no reported cases of Marburg in humans there. However, the virus’s presence in bats means people who live nearby could be at risk for becoming infected with Marburg virus, a cousin to Ebola virus that causes similar disease in people.

    The Marburg virus co-discovery occurred through two projects — one by the USAID-funded PREDICT project led by University of California, Davis, and the University of Makeni; and another by Centers for Disease Control and Prevention and Njala University.

    “That the discovery was made in bats before the recognition of any known human illnesses or deaths is exactly what PREDICT’s One Health approach to disease surveillance and capacity building are designed to do,” said Brian Bird from the UC Davis One Health Institute and global lead for Sierra Leone and Multi-Country Ebola operations for PREDICT-USAID.

    Natural reservoir

    Scientists had previously shown that the Egyptian rousette bat (Rousettus aegyptiacus) is the natural reservoir for Marburg virus, which means the bats can carry the virus long-term and pass it on to animals or humans without getting sick themselves. Sequencing of virus genetic material from the five Marburg-positive bats found multiple genetically diverse strains, suggesting Marburg virus has been present in these bat colonies in Sierra Leone for many years.

    “We have known for a long time that the bats that carry Marburg virus live in West Africa, so it makes sense that we’d find the virus in bats there,” said CDC ecologist Jonathan Towner, who led the CDC team. “This discovery is an excellent example of how this type of ecology work can help us identify a threat and warn people before they get sick.”

    2
    Thousands of Egyptian fruit bats roost in a cave in Uganda’s Queen Elizabeth National Park. (Getty)

    Egyptian fruit bats live in caves or underground mines throughout much of Africa. Marburg virus has been detected in Egyptian rousette bats caught in sub-Saharan Africa, primarily in Uganda and the Democratic Republic of Congo, but also Gabon, Kenya and South Africa. In eastern and central Africa, these bats can roost in colonies of more than 100,000 animals.

    However, the colonies of Egyptian fruit bats identified in Sierra Leone so far have been much smaller, which may explain why there haven’t been any known Marburg virus disease outbreaks in people in Sierra Leone like those found in eastern and central Africa.

    Angolan strains detected in bats for first time

    To date, there have been 12 known Marburg virus outbreaks with direct links to Africa, with the most recent in Uganda in 2017. The largest and deadliest Marburg virus outbreak occurred in Angola in 2005. It killed 227 of 252 cases, or about 90 percent of those infected. Two of the four strains identified among the five Marburg-positive bats in Sierra Leone are genetically similar to the strain that caused the outbreak in Angola. It is the first time scientists have detected these Angolan strains in bats.

    Egyptian rousette bats primarily feed on fruit. When infected, the bats shed the virus in their saliva, urine and feces. These Egyptian rousette bats are known to test-bite fruits, urinate and defecate where they eat, potentially contaminating fruit or other food sources consumed by other animals like monkeys or people, particularly children. Due to their significant size, these types of bats sometimes serve as a food source for local populations, as well. People may be exposed to Marburg virus through bat bites as they catch the bats.

    Community engagement

    In Sierra Leone, researchers and government officials are in the process of meeting with local communities to present their findings, answer questions about Marburg virus, and address how to reduce people’s risk of exposure and live safely with bats.

    Bats play important ecological and agricultural roles. Fruit bats pollinate important crops, and insect-eating bats eat thousands of insects each night, including mosquitoes, which helps control pests that transmit disease and damage crops.

    Scientists emphasize that people should not attempt to kill or eradicate bats in response to the discovery. Killing and coming into direct contact with bats can actually increase the risk of virus transmission, not halt it.

    Finding viruses before they find us

    The PREDICT team at UC Davis/University of Makeni and the team led by CDC/Njala both began work in Sierra Leone in 2016 following the massive Ebola outbreak in West Africa. They each sought to discover the Ebola reservoir, the animal that helps maintain the virus in nature by spreading it without getting sick.

    The Marburg discovery and the PREDICT-team’s report earlier this year of the discovery of a new ebolavirus species, Bombali virus, illustrate the strengths and mission of USAID’s PREDICT project, which is to find viruses before they spill over into humans and become epidemics.

    Media contact(s)

    Brian Bird, UC Davis PREDICT and One Health Institute, 530-752-7544, bhbird@ucdavis.edu

    Tracey Goldstein, UC Davis PREDICT and One Health Institute, 415-902-1486, tgoldstein@ucdavis.edu

    Kat Kerlin, UC Davis News and Media Relations, 530-752-7704, kekerlin@ucdavis.edu

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Davis Campus

    The University of California, Davis, is a major public research university located in Davis, California, just west of Sacramento. It encompasses 5,300 acres of land, making it the second largest UC campus in terms of land ownership, after UC Merced.

     
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