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  • richardmitnick 7:16 pm on May 22, 2019 Permalink | Reply
    Tags: , , carbon and ice, , , , Most people behave differently when under extreme pressure. Carbon and ice are no different., , UCLA   

    From UCLA Newsroom: “New insights about carbon and ice could clarify inner workings of Earth, other planets” 


    From UCLA Newsroom

    Media Contact

    Stuart Wolpert
    UCLA
    310-206-0511
    swolpert@stratcomm.ucla.edu

    May 22, 2019
    Christopher Crockett

    1
    New simulations suggest that carbon (C) routinely bonded with iron (Fe), silicon (Si) and oxygen (O) deep within the magma ocean that covered Earth when it was young. Natalia Solomatova/École Normale Supérieure de Lyon.

    2
    ORNL super-cold states of water. phys.org

    Most people behave differently when under extreme pressure. Carbon and ice are no different.

    Two new studies show how these key planetary ingredients take on exotic forms that could help researchers better understand the composition of Earth’s core as well as the cores of planets across the galaxy. Craig Manning, a UCLA professor of geology and geochemistry, is a co-senior author of one of the papers, which was published today in the journal Nature, and senior author of the other, which was published in Nature Communications in February.

    The Nature Communications paper revealed that high pressure deep inside the young Earth may have driven vast stores of carbon into the planet’s core while also setting the stage for diamonds to form. In the Nature report, researchers found that water ice undergoes a complex crystalline metamorphosis as the pressure slowly ratchets up.

    Scientists have long understood that the amount of carbon sequestered in present-day Earth’s rocks, oceans and atmosphere is always in flux because the planet shuffles the element around in a vast cycle that helps regulate climate. But researchers don’t know whether the Earth locked away even more carbon deep in its interior during its formative years — information that could reveal a little more about how our planet and others like it are built.

    To pursue an answer to that question, Manning and colleagues calculated how carbon might have interacted with other atoms under conditions similar to those that prevailed roughly 4.5 billion years ago, when much of Earth was still molten. Using supercomputers, the team created simulations to explore what would happen to carbon at temperatures above 3,000 degrees Celsius (more than 5,400 degrees Fahrenheit) and at pressures more than 100,000 times of those on Earth’s surface today.

    The experiment revealed that under those conditions, carbon tends to link up with iron, which implies that there might be considerable quantities of carbon sealed in Earth’s iron core today. Researchers had already suspected that in the young planet’s magma ocean, iron atoms hooked up with one another and then dropped to the planet’s center. But the new research suggests that this molten iron rain may have also dragged carbon down with it. Until now, researchers weren’t even sure whether carbon exists down there.

    The team also found that as the pressure ramps up, carbon increasingly bonds with itself, forming long chains of carbon atoms with oxygen atoms sticking out.

    “These complex chains are a form of carbon bonding that we really hadn’t anticipated at these conditions,” Manning said.

    Such molecules could be a precursor to diamonds, which consist of many carbon atoms linked together.

    Solving an icy enigma

    The machinations of carbon under pressure provide clues as to how Earth-like planets are built. Frozen planets and moons in other solar systems, however, may also have to contend with water ice. In a separate paper, Manning and another team of scientists looked at how the molecular structure of extremely cold ice changes when put under intense pressure.

    Under everyday conditions, water ice is made up of molecules laid out in honeycomb-like mosaics of hexagons. But when ice is exposed to crushing pressure or very low temperature — in labs or possibly deep inside remote worlds — the molecules can assume a bewildering variety of patterns.

    One of those patterns, known as amorphous ice, is an enigma. In amorphous ice, the water molecules eschew rigid crystalline order and take on a free-form arrangement. Manning and colleagues set out to try and understand how amorphous ice forms.

    First, they chilled normal ice to about 170 degrees below zero Celsius (about 274 degrees below zero Fahrenheit). Then, they locked the ice in the jaws of a high-tech vice grip inside a cryogenic vacuum chamber. Finally, over the span of several hours, they slowly stepped up the pressure in the chamber to about 15,000 times atmospheric pressure. They stopped raising the pressure periodically to fire neutrons through the ice so that they could see the arrangement of the water molecules.

    Surprisingly to the researchers, the amorphous ice never formed. Instead, the molecules went through a series of previously known crystalline arrangements.

    However, when the researchers conducted the same experiment but raised the pressure much more rapidly — this time in just 30 minutes — amorphous ice formed as expected. The results suggest that time is the secret ingredient: When pressure increases slowly, tiny seeds of crystalline ice have time to form and take over the sample. Otherwise, those seeds never get a chance to grow.

    The findings, published May 23 in the journal Nature [above], could be useful to researchers who study worlds orbiting other suns and are curious about what conditions might be like deep inside frozen planets.

    “It’s entirely likely that there are planets dominated by ice in other solar systems that could obtain these pressures and temperatures with ease,” Manning said. “We have to have this right if we’re going to have a baseline for understanding the interiors of cold worlds that may not be like Earth.”

    Both papers were funded in part by the Deep Carbon Observatory, a 10-year program started in 2009 to investigate the quantities, movements, forms and origins of deep carbon inside Earth. The Nature Communications paper was also funded by the European Research Council and was co-authored by researchers at the Ecole Normale Supérieure de Lyon in France, one of whom — Natalia Solomatova — completed her undergraduate studies at UCLA. The Nature paper was co-authored by UCLA geologist Adam Makhluf and researchers from Oak Ridge National Laboratory and the National Research Council of Canada.

    See the full article here .
    See also in phys.org here.


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 2:36 pm on March 8, 2019 Permalink | Reply
    Tags: "New UCLA fellowship aims to make environmental science more inclusive", “Diversity provides comfort in a work environment and shows that you can do anything despite your race religious beliefs or sexuality” said Thompson., “If you don’t have women in science you’re missing some of that talent pool” McKinnon said., “The experience of having only a small number of female peers was challenging because you always felt just a little bit out of place” said Karen McKinnon of UCLA, Center for Diverse Leadership in Science’s inaugural fellows seek to build network of support., Change is coming in the demographics of science and like most things the earliest examples come from California, Climate change touches every life on the planet — so why are so many environmental scientists white men?, In the United States 86 percent of the environmental science workforce is white and 70 percent is male., Its goal: to inspire a generation of leaders that actually matches the demographics of the U.S. population., Lack of diversity in such programs can have global implications when it comes to environmental issues., Last year UCLA became the first university to launch a center for diversity in environmental science to counter the problem., Next year Thompson will be paired with a faculty fellow for one-on-one mentorship a cornerstone of the fellowship program., Ronald Thompson a second-year environmental science student from Sacramento said he is one of few black students in most of his classes, The fellows aim to break barriers that prevent women and minorities from pursuing academic careers in the sciences through group collaboration., The inaugural fellows class consists of 47 high school undergraduate students graduate students and postdoctoral researchers along with 22 faculty fellows from UCLA., UCLA   

    From UCLA Newsroom: “New UCLA fellowship aims to make environmental science more inclusive” 


    From UCLA Newsroom

    March 07, 2019
    Sonia Aronson

    Center for Diverse Leadership in Science’s inaugural fellows seek to build network of support.

    1
    Justin Caram, assistant professor of chemistry and biochemistry in the UCLA College, and graduate student Dayanni Bhagwandin.

    Climate change touches every life on the planet — so why are so many environmental scientists white men?

    Last year, UCLA became the first university to launch a center for diversity in environmental science to counter the problem. Its goal: to inspire a generation of leaders that actually matches the demographics of the U.S. population.

    This year, the Center for Diverse Leadership in Science’s first class of fellows takes flight, building a critical mass to ensure students and faculty of diverse backgrounds have what they’ll need to succeed, from funding to a supportive community of scientists with similar backgrounds.

    “With challenges like climate change, the stakes have never been higher for ensuring we have scientific literacy coupled with representation and innovation,” said Aradhna Tripati, the center’s founder and a UCLA climate scientist. “We need every person’s imagination to overcome some of the greatest challenges our society has faced.”

    Karen McKinnon, a professor in the UCLA Institute of the Environment and Sustainability knows only too well how that sense of isolation affects a student. As one of just a few women in her doctoral program, McKinnon experienced first-hand what it’s like to be a minority in an academic setting.

    “The experience of having only a small number of female peers was challenging because you always felt just a little bit out of place,” said McKinnon, who is also a professor of statistics. “It was a visual reminder that I was not the ‘typical’ scientist.”

    In the United States, 86 percent of the environmental science workforce is white and 70 percent is male, despite the fact that the EPA found in a 2018 study that non-white communities had a 28 percent higher health burden from environmental issues. Those under the poverty line had a 35 percent higher health burden.

    The inaugural fellows class consists of 47 high school, undergraduate students, graduate students and postdoctoral researchers, along with 22 faculty fellows from UCLA. The students will work in groups on research and outreach campaigns while the faculty fellows serve as mentors and role models.

    2
    Postdoctoral scientist Adeyemi Adebiyi and Jasper Kok, associate professor of atmospheric and oceanic sciences.

    The fellows aim to break barriers that prevent women and minorities from pursuing academic careers in the sciences through group collaboration, workshop training sessions and community outreach. Students are paid for their work with financial support from the National Science Foundation and private donations.

    Ronald Thompson, a second-year environmental science student from Sacramento, said he is one of few black students in most of his classes.

    “Diversity provides comfort in a work environment and shows that you can do anything despite your race, religious beliefs or sexuality,” said Thompson, who wants to pursue a research career in conservation biology. “It lets you be comfortable with what you’re doing and makes you feel like you’re not being judged or looked at differently.”

    For his research component of the fellowship, Thompson works with other undergraduates in a group overseen by a doctoral candidate to analyze sediment from ancient lakes across the western United States. Their research aims to discover how those lakes persisted through past changes in climate — and how they might react to modern climate change. While the work is fulfilling, Thompson said the best part is working with others just as passionate as himself about the environment.

    “People go above and beyond what is required of them out of pure passion for the work they do,” Thompson said. “Everyone wants to be a part of the change that promotes a better future.”

    Next year, Thompson will be paired with a faculty fellow for one-on-one mentorship, a cornerstone of the fellowship program.

    Having a continuum of scientists at all levels — from high school students to professors — is an effective strategy to build professional communities for disenfranchised groups, Tripati said.

    “Homogenous environments cause feelings of isolation which can be detrimental to success,” Tripati said.

    Lack of diversity in such programs can have global implications when it comes to environmental issues, she added.

    “If you don’t have women in science, you’re missing some of that talent pool,” McKinnon said. “There remain a lot of fundamental questions to answer about how the climate system responds to human influence.”

    One way to make students more comfortable in class is to encourage teachers to embrace inclusive teaching techniques, said Jasper Kok, who is one of the faculty fellows and an associate professor of atmospheric and oceanic sciences in the UCLA College. Every class includes a 10-minute exercise during which students work with their neighbors.

    “Techniques that engage students and let them work collaboratively help those students who feel like they don’t belong feel more at home and more likely to stay in that field,” he said.

    For student fellow Thompson, the benefits are more personal.

    “It’s an opportunity to give back to communities and be a role model to other college students, high school students and middle school students,” he said.

    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 LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 11:59 am on February 21, 2019 Permalink | Reply
    Tags: "Rare L.A. mega-storm could overwhelm dam and flood dozens of cities experts say", A government study however used computer models to estimate the effects of 900-year 7500-year and 18000-year storm events, Epic runoff from the San Gabriel Mountains could rapidly overwhelm a flood control dam on the San Gabriel river and unleash floodwaters from Pico Rivera to Long Beach says a recent analysis by the U.S, In a series of recent public hearings corps officials told residents that the 60-year-old Whittier Narrows Dam no longer met the agency’s tolerable-risk guidelines and could fail in the event of a v, In each case catastrophic flooding could extend from Pico Rivera to Long Beach inundating cities including Artesia Bell Gardens Bellflower Carson Cerritos Commerce Compton Cypress Downey Hawaiian Gard, , Scientists call it California’s “other big one”- what experts call an ARkStorm, This rare mega-storm — which some say is rendered all the more inevitable due to climate change — would last for weeks and send more than 1.5 million people fleeing as floodwaters inundated cities, UCLA, Whittier Narrows Dam   

    From L.A. Times via UCLA: “Rare L.A. mega-storm could overwhelm dam and flood dozens of cities, experts say” 

    From L.A. Times

    via

    UCLA bloc

    UCLA

    Feb 18, 2019
    Louis Sahagun

    1
    Lead engineer Douglas Chitwood at the Whittier Narrows Dam. The U.S. Army Corps of Engineers says the aging structure could fail in heavy rains. (Irfan Khan / Los Angeles Times)

    Scientists call it California’s “other big one,” and they say it could cause three times as much damage as a major earthquake ripping along the San Andreas Fault.

    Although it might sound absurd to those who still recall five years of withering drought and mandatory water restrictions, researchers and engineers warn that California may be due for rain of biblical proportions — or what experts call an ARkStorm.

    2
    (Los Angeles Times)

    This rare mega-storm — which some say is rendered all the more inevitable due to climate change — would last for weeks and send more than 1.5 million people fleeing as floodwaters inundated cities and formed lakes in the Central Valley and Mojave Desert, according to the U.S. Geological Survey. Officials estimate the structural and economic damage from an ARkStorm (for Atmospheric River 1,000) would amount to more than $725 billion statewide.

    In heavily populated areas of the Los Angeles Basin, epic runoff from the San Gabriel Mountains could rapidly overwhelm a flood control dam on the San Gabriel river and unleash floodwaters from Pico Rivera to Long Beach, says a recent analysis by the U.S. Army Corps of Engineers.

    3
    An aerial view of the Whittier Narrows Dam in the area between Montebello and Pico Rivera. (Brian van der Brug / Los Angeles Times)

    In a series of recent public hearings, corps officials told residents that the 60-year-old Whittier Narrows Dam no longer met the agency’s tolerable-risk guidelines and could fail in the event of a very large, very rare storm, such as the one that devastated California more than 150 years ago.

    Specifically, federal engineers found that the Whittier Narrows structure could fail if water were to flow over its crest or if seepage eroded the sandy soil underneath. In addition, unusually heavy rains could trigger a premature opening of the dam’s massive spillway on the San Gabriel River, releasing more than 20 times what the downstream channel could safely contain within its levees.

    The corps is seeking up to $600 million in federal funding to upgrade the 3-mile-long dam, and say the project has been classified as the agency’s highest priority nationally, due to the risk of “very significant loss of life and economic impacts.”

    The funding will require congressional approval, according to Doug Chitwood, lead engineer on the project.

    Standing atop the 56-foot-tall dam recently, Chitwood surveyed the sprawl of working-class homes, schools and commercial centers about 13 miles south of Los Angeles and said, “All you see could be underwater.”

    4
    Engineer Douglas Chitwood explains the workings of the Whittier Narrows Dam, which engineers predict would not stand up to a mega-storm. (Irfan Khan / Los Angeles Times)

    The dam — which stretches from Montebello to Pico Rivera and crosses both the San Gabriel and Rio Hondo rivers — is one of a number of flood control facilities overseen by the corps. Throughout much of the year, it contains little water.

    A government study, however, used computer models to estimate the effects of 900-year, 7,500-year and 18,000-year storm events.

    5
    (Los Angeles Times)

    In each case, catastrophic flooding could extend from Pico Rivera to Long Beach, inundating cities including Artesia, Bell Gardens, Bellflower, Carson, Cerritos, Commerce, Compton, Cypress, Downey, Hawaiian Gardens, La Palma, Lakewood, Long Beach, Lynwood, Montebello, Norwalk, Paramount, Rossmoor, Santa Fe Springs, Seal Beach and Whittier. Officials say as many as 1 million people could be affected.

    Among the communities hardest hit in a dam failure would be Pico Rivera, a city of about 63,000 people immediately below the dam. In a worst-case scenario, it could be hit with water 20 feet deep, and evacuation routes would be turned into rivers. Downey could see 15 feet of water; Santa Fe Springs, 10 feet.

    In recent years, officials with the U.S. Department of Interior and the U.S. Geological Survey have sought to raise awareness of the threat of mega-storms and promote emergency preparedness. Part of the challenge, however, has been characterizing the scale of such storms. When scientists speak of a 900-year storm, that does not mean the storm will occur every 900 years, or that such a storm cannot happen two years in a row. It means that such a storm has a 1 in 900 — or .1% — chance of occurring in any given year.

    The estimates used by the U.S. Army Corps of Engineers are intended to protect the region from a storm similar to the one that hit California during the rainy season of 1861-1862. That’s when a series of intense storms hammered the state for 45 days and dropped 36 inches of rain on Los Angeles. So much water fell that it was impossible to cross the Central Valley without a boat, and the state capital was moved temporarily from Sacramento to San Francisco.

    Some researchers, however, say climate change has cast doubt on 20th-century assumptions. They argue [nature climate change] that, in a warming world, regions such as California will experience more whiplashing shifts between extremely dry and extremely wet periods — similar to how California’s long drought was quickly followed by the wettest rainy season on record in 2016-2017. These intense cycles will seriously challenge California’s ability to control flooding as well as store and transport water.

    Daniel Swain, a UCLA climate scientist, said hydrological and forecast data used by the corps must be updated.

    “The Army Corps’ estimates of the impacts of an extremely serious weather event … are categorically underestimated,” he said. “That’s because we only have about a century of records to refer to in California. So, they are extrapolating in the dark.”

    As an example, Swain said until recently it was thought a flood the magnitude of the 1861-1862 event was likely to occur every 1,000 to 10,000 years. New research has changed that view considerably, Swain said.

    “A newer study suggests the chances of seeing another flood of that magnitude over the next 40 years are about 50-50,” he said.

    Whittier Narrows, Swain added, is therefore just one of “many pieces of water infrastructure that may not be up to the challenge of the brave new climate of the 21st century.”

    4
    Men ride horseback in the shadow of Whittier Narrows Dam, which Army Corp of Engineers officials say no longer meets their tolerable-risk guidelines. (Irfan Khan / Los Angeles Times)

    Such was the conclusion of a study conducted by UC Irvine researchers and published recently in the scientific journal Geophysical Research Letters. After examining 13 California reservoirs — most of them over 50 years old — the authors argued that the risk of dam failure was likely to increase in a warming climate. The study cited the 2017 crisis at Oroville Dam, when extreme water flows caused the dam spillway to disintegrate and triggered the evacuation of more than 180,000 people.

    In the case of Whittier Narrows Dam, Travis Longcore, a spatial scientist at USC, suggested people had grown complacent about the effectiveness of the area’s flood control system. “People tend to forget about the power of Southern California’s river systems,” he said.

    The San Gabriel River ranks among the steepest rivers in the United States, plunging 9,900 feet from boulder-strewn forks in the mountains down to Irwindale. It then meanders in a gravelly channel before arriving at lush Whittier Narrows — a natural gap in the hills that form the southern boundary of the San Gabriel Valley. From there, its flows are tamed in a concrete-covered channel for most of its final journey to the Pacific Ocean.

    Now, based on the corps’ findings, L.A. County and municipal officials are working with the federal government to develop emergency plans that can be implemented if necessary before the repair project at the dam is completed in 2026.

    Pico Rivera has undertaken an improved preparedness program, but only recently.

    Robert Alaniz, a spokesman for Pico Rivera, said the city was using a $300,000 grant from the California Department of Water Resources to revise its existing evacuation plans, which use major thoroughfares crossing the San Gabriel River to the east and Rio Hondo to the west.

    Separately, Los Angeles County Supervisor Hilda Solis said she discussed the importance of the Whittier Narrows Dam project with members of Congress during a visit to Washington, D.C., in January.

    In the meantime, David Reid, a water historian and expert on the Whittier Narrows area, suggested “the false sense of security included in the phrase ‘900-year flood’ combined with the promises of 20th century water infrastructure have put us in a bind.”

    “That’s because a mega-flood is impossible to predict,” he said. “And if the water infrastructure fails, we’re in big trouble.”

    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 LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 11:09 am on January 23, 2019 Permalink | Reply
    Tags: , , , , H0liCOW collaboration, , Quasar SDSS J1206+4332, Seeing double could help resolve dispute about how fast the universe is expanding, UCLA   

    From UCLA Newsroom: “Seeing double could help resolve dispute about how fast the universe is expanding” 


    From UCLA Newsroom

    January 22, 2019
    Christopher Crockett

    1
    A Hubble Space Telescope picture of a doubly imaged quasar. NASA Hubble Space Telescope, Tommaso Treu/UCLA, and Birrer et al.

    The question of how quickly the universe is expanding has been bugging astronomers for almost a century. Different studies keep coming up with different answers — which has some researchers wondering if they’ve overlooked a key mechanism in the machinery that drives the cosmos.

    Now, by pioneering a new way to measure how quickly the cosmos is expanding, a team led by UCLA astronomers has taken a step toward resolving the debate. The group’s research is published today in Monthly Notices of the Royal Astronomical Society.

    At the heart of the dispute is the Hubble constant, a number that relates distances to the redshifts of galaxies — the amount that light is stretched as it travels to Earth through the expanding universe. Estimates for the Hubble constant range from about 67 to 73 kilometers per second per megaparsec, meaning that two points in space 1 megaparsec apart (the equivalent of 3.26 million light-years) are racing away from each other at a speed between 67 and 73 kilometers per second.

    “The Hubble constant anchors the physical scale of the universe,” said Simon Birrer, a UCLA postdoctoral scholar and lead author of the study. Without a precise value for the Hubble constant, astronomers can’t accurately determine the sizes of remote galaxies, the age of the universe or the expansion history of the cosmos.

    Most methods for deriving the Hubble constant have two ingredients: a distance to some source of light and that light source’s redshift. Looking for a light source that had not been used in other scientists’ calculations, Birrer and colleagues turned to quasars, fountains of radiation that are powered by gargantuan black holes. And for their research, the scientists chose one specific subset of quasars — those whose light has been bent by the gravity of an intervening galaxy, which produces two side-by-side images of the quasar on the sky.

    Light from the two images takes different routes to Earth. When the quasar’s brightness fluctuates, the two images flicker one after another, rather than at the same time. The delay in time between those two flickers, along with information about the meddling galaxy’s gravitational field, can be used to trace the light’s journey and deduce the distances from Earth to both the quasar and the foreground galaxy. Knowing the redshifts of the quasar and galaxy enabled the scientists to estimate how quickly the universe is expanding.

    The UCLA team, as part of the international H0liCOW collaboration, had previously applied the technique to study quadruply imaged quasars, in which four images of a quasar appear around a foreground galaxy. But quadruple images are not nearly as common — double-image quasars are thought to be about five times as abundant as the quadruple ones.

    To demonstrate the technique, the UCLA-led team studied a doubly imaged quasar known as SDSS J1206+4332; they relied on data from the Hubble Space Telescope, the Gemini and W.M. Keck observatories, and from the Cosmological Monitoring of Gravitational Lenses, or COSMOGRAIL, network — a program managed by Switzerland’s Ecole Polytechnique Federale de Lausanne that is aimed at determining the Hubble constant.

    NASA/ESA Hubble Telescope

    Gemini/North telescope at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level

    Keck Observatory, Maunakea, Hawaii, USA.4,207 m (13,802 ft), above sea level,

    2

    Tommaso Treu, a UCLA professor of physics and astronomy and the paper’s senior author, said the researchers took images of the quasar every day for several years to precisely measure the time delay between the images. Then, to get the best estimate possible of the Hubble constant, they combined the data gathered on that quasar with data that had previously been gathered by their H0liCOW collaboration on three quadruply imaged quasars.

    “The beauty of this measurement is that it’s highly complementary to and independent of others,” Treu said.

    The UCLA-led team came up with an estimate for the Hubble constant of about 72.5 kilometers per second per megaparsec, a figure in line with what other scientists had determined in research that used distances to supernovas — exploding stars in remote galaxies — as the key measurement. However, both estimates are about 8 percent higher than one that relies on a faint glow from all over the sky called the cosmic microwave background, a relic from 380,000 years after the Big Bang, when light traveled freely through space for the first time.

    “If there is an actual difference between those values, it means the universe is a little more complicated,” Treu said.

    On the other hand, Treu said, it could also be that one measurement — or all three — are wrong.

    The researchers are now looking for more quasars to improve the precision of their Hubble constant measurement. Treu said one of the most important lessons of the new paper is that doubly imaged quasars give scientists many more useful light sources for their Hubble constant calculations. For now, though, the UCLA-led team is focusing its research on 40 quadruply imaged quasars, because of their potential to provide even more useful information than doubly imaged ones.

    Sixteen other researchers from 13 institutions in seven countries contributed to the paper; the research was supported in part by grants from NASA, the National Science Foundation and the Packard 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 LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 5:53 pm on November 12, 2018 Permalink | Reply
    Tags: , , , MicroED-micro-electron diffraction, , NMR-nuclear magnetic resonance, , UCLA, ,   

    From Caltech: “From Beaker to Solved 3-D Structure in Minutes” 

    Caltech Logo

    From Caltech

    11/12/2018

    Whitney Clavin
    (626) 395-1856
    wclavin@caltech.edu

    1
    Graduate student Tyler Fulton prepares samples of small molecules in a lab at Caltech. Credit: Caltech

    2
    Close-up of a powder containing small molecules like those that gave rise to 3-D structures in the new study. (The copper piece is a sample holder used with microscopes.) Credit: Caltech/Stoltz Lab

    3
    Brian Stoltz and Tyler Fulton. Credit: Caltech

    UCLA/Caltech team uncovers a new and simple way to learn the structures of small molecules.

    In a new study that one scientist called jaw-dropping, a joint UCLA/Caltech team has shown that it is possible to obtain the structures of small molecules, such as certain hormones and medications, in as little as 30 minutes. That’s hours and even days less than was possible before.

    The team used a technique called micro-electron diffraction (MicroED), which had been used in the past to learn the 3-D structures of larger molecules, specifically proteins. In this new study, the researchers show that the technique can be applied to small molecules, and that the process requires much less preparation time than expected. Unlike related techniques—some of which involve growing crystals the size of salt grains—this method, as the new study demonstrates, can work with run-of-the-mill starting samples, sometimes even powders scraped from the side of a beaker.

    “We took the lowest-brow samples you can get and obtained the highest-quality structures in barely any time,” says Caltech professor of chemistry Brian Stoltz, who is a co-author on the new study, published in the journal ACS Central Science. “When I first saw the results, my jaw hit the floor.” Initially released on the pre-print server Chemrxiv in mid-October, the article has been viewed more than 35,000 times.

    The reason the method works so well on small-molecule samples is that while the samples may appear to be simple powders, they actually contain tiny crystals, each roughly a billion times smaller than a speck of dust. Researchers knew about these hidden microcrystals before, but did not realize they could readily reveal the crystals’ molecular structures using MicroED. “I don’t think people realized how common these microcrystals are in the powdery samples,” says Stoltz. “This is like science fiction. I didn’t think this would happen in my lifetime—that you could see structures from powders.”

    4
    This movie [animated in the full article] is an example of electron diffraction (MicroED) data collection, in which electrons are fired at a nanocrystal while being continuously rotated. Data from the movie are ultimately converted to a 3-D chemical structure. Credit: UCLA/Caltech

    The results have implications for chemists wishing to determine the structures of small molecules, which are defined as those weighing less than about 900 daltons. (A dalton is about the weight of a hydrogen atom.) These tiny compounds include certain chemicals found in nature, some biological substances like hormones, and a number of therapeutic drugs. Possible applications of the MicroED structure-finding methodology include drug discovery, crime lab analysis, medical testing, and more. For instance, Stoltz says, the method might be of use in testing for the latest performance-enhancing drugs in athletes, where only trace amounts of a chemical may be present.

    “The slowest step in making new molecules is determining the structure of the product. That may no longer be the case, as this technique promises to revolutionize organic chemistry,” says Robert Grubbs, Caltech’s Victor and Elizabeth Atkins Professor of Chemistry and a winner of the 2005 Nobel Prize in Chemistry, who was not involved in the research. “The last big break in structure determination before this was nuclear magnetic resonance spectroscopy, which was introduced by Jack Roberts at Caltech in the late ’60s.”

    Like other synthetic chemists, Stoltz and his team spend their time trying to figure out how to assemble chemicals in the lab from basic starting materials. Their lab focuses on such natural small molecules as the fungus-derived beta-lactam family of compounds, which are related to penicillins. To build these chemicals, they need to determine the structures of the molecules in their reactions—both the intermediate molecules and the final products—to see if they are on the right track.

    One technique for doing so is X-ray crystallography, in which a chemical sample is hit with X-rays that diffract off its atoms; the pattern of those diffracting X-rays reveals the 3-D structure of the targeted chemical. Often, this method is used to solve the structures of really big molecules, such as complex membrane proteins, but it can also be applied to small molecules. The challenge is that to perform this method a chemist must create good-sized chunks of crystal from a sample, which isn’t always easy. “I spent months once trying to get the right crystals for one of my samples,” says Stoltz.

    Another reliable method is NMR (nuclear magnetic resonance), which doesn’t require crystals but does require a relatively large amount of a sample, which can be hard to amass. Also, NMR provides only indirect structural information.

    Before now, MicroED—which is similar to X-ray crystallography but uses electrons instead of X-rays—was mainly used on crystallized proteins and not on small molecules. Co-author Tamir Gonen, an electron crystallography expert at UCLA who began developing the MicroED technique for proteins while at the Howard Hughes Medical Institute in Virginia, said that he only started thinking about using the method on small molecules after moving to UCLA and teaming up with Caltech.

    “Tamir had been using this technique on proteins, and just happened to mention that they can sometimes get it to work using only powdery samples of proteins,” says Hosea Nelson (PhD ’13), an assistant professor of chemistry and biochemistry at UCLA. “My mind was blown by this, that you didn’t have to grow crystals, and that’s around the time that the team started to realize that we could apply this method to a whole new class of molecules with wide-reaching implications for all types of chemistry.”

    The team tested several samples of varying qualities, without ever attempting to crystallize them, and were able to determine their structures thanks to the samples’ ample microcrystals. They succeeded in getting structures for ground-up samples of the brand-name drugs Tylenol and Advil, and they were able to identify distinct structures from a powdered mixture of four chemicals.

    The UCLA/Caltech team says it hopes this method will become routine in chemistry labs in the future.

    “In our labs, we have students and postdocs making totally new and unique molecular entities every day,” says Stoltz. “Now we have the power to rapidly figure out what they are. This is going to change synthetic chemistry.”

    The study was funded by the National Science Foundation, the National Institutes of Health, the Department of Energy, a Beckman Young Investigators award, a Searle Scholars award, a Pew Scholars award, the Packard Foundation, the Sloan Foundation, the Pew Charitable Trusts, and the Howard Hughes Medical Institute. Other co-authors include Christopher Jones,Michael Martynowycz, Johan Hattne, and Jose Rodriguez of UCLA; and Tyler Fulton of Caltech.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus


    Caltech campus

     
  • richardmitnick 8:07 am on August 29, 2018 Permalink | Reply
    Tags: , , , , Jupiter's moons Europa and Ganymede, UCLA   

    From UCLA Newsroom: “‘Chorus waves’ near Jupiter’s moons are explained in new research” 


    From UCLA Newsroom

    August 28, 2018
    Lisa Y. Garibay

    Two UCLA space scientists contribute to study of Europa and Ganymede.

    1
    Natural color view of Ganymede from the Galileo spacecraft during its first encounter with the satellite. (NASA/JPL)

    In 1996, scientists discovered the presence of plasma waves near Ganymede, one of Jupiter’s moons. Those waves, similar in some ways to waves on the surface of water, are often referred to as “chorus waves,” because they can be played thorough a radio and sound something like a choir.

    Until now, it remained unclear if the increases in wave power that the scientists observed were accidental increases associated with natural variability or were systematic and significant. A team of scientists that includes two UCLA researchers has published a study in Nature Communications that might explain the phenomenon.

    The research reports that chorus wave power is increased by up to a million times near Ganymede, and up to 100 times near Europa, another of Jupiter’s moons.

    “It’s really a surprising and puzzling observation showing that a bare presence of the magnetized object can create such a tremendous intensification in the power of waves,” said Yuri Shprits, the study’s first author and a researcher in the department of Earth, planetary and space sciences in the UCLA College.

    Alexander Drozdov, a UCLA assistant researcher, was one of the study’s co-authors.

    More:

    he planet Jupiter has a very strong magnetic field which forms the largest object in the solar physics. Observations of Jupiter’s magnetosphere in the 1990s provided a unique opportunity to understand how magnetic fields interact with particles and how moons of Jupiter can change the environment of the gas giant. One of the most surprising and fascinating discoveries about the moons of the giant planet was made by UCLA’s Margaret Kivelson – a professor emerita in the Department of Earth, Planetary, and Space Sciences – and her team, who found the internal magnetic field on Jupiter’s moon Ganymede.

    In 1996, a team of scientists led by University of Iowa Professor Don Gurnett noticed that strong plasma waves were observed near Ganymede. These waves are similar to waves observed on the surface of the water. However, unlike water waves, it is electric and magnetic fields which increase and decrease during these oscillations. The particular type of waves that they observed are often referred to as “chorus waves,” as they can be played thorough a radio and the sound similar to a multi-voiced chorus.

    Until now, it remained unclear if these observed increases in wave power represented accidental increases associated with natural variability, or if they were systematic and significant. A study published recently in Nature Communications may clear this up.

    The study reports that chorus wave power is increased by up to a factor of million near Ganymede, and up to a factor of 100 near neighboring moon Europa. “It’s really a surprising and puzzling observation showing that a bare presence of the magnetized object can create such a tremendous intensification in the power of waves,” said Yuri Shprits, first author of the study and a researcher in UCLA’s Department of Earth, Planetary, and Space Sciences (EPSS) as well as a professor at GFZ-Potstam/University of Potsdam.

    2

    Similar chorus waves in Earth’s magnetosphere are responsible for accelerating space particles to very high energies, producing so-called “killer electrons,” which are so energetic that they can penetrate a satellite’s shielding and damage or completely knock it down. These processes are also likely to occur in Jupiter’s magnetosphere, says UCLA EPSS assistant researcher Alexander Drozdov, who is a co-author of the study. He and his fellow researchers performed a systematic study of Jupiter’s wave environment and compared average measurements to satellite flybys.

    These observations provided a unique opportunity to understand the fundamental physical processes that may be relevant to laboratory plasmas, as well as processes of acceleration and loss near Earth and in the distant corners of the universe. Similar processes may occur in exoplanetary environments. Thus, the work done by these researchers may help detect the magnetic fields of exoplanets being sought after by many planetary scientists.

    According to Drozdov, this study heralds a greater understanding of plasma dynamics for researchers studying plasmas both in space and in laboratories on Earth.

    “By observing the fundamental process of how particles and waves interact in plasma on Jupiter, it creates important benchmarks for theorists to test their models using this truly remarkable experience that nature’s provided for us,” Shprits added.

    This research was supported by NASA and is a result of collaboration of UCLA, German Research Center for Geosciences, University of Potsdam, University of Iowa, British Antarctic Survey, Jet Propulsion Laboratory, and Applied Physics Lab.

    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 LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 7:30 am on February 2, 2018 Permalink | Reply
    Tags: Educating for equity and access in computer science, UCLA   

    From UCLA: “Educating for equity and access in computer science” 


    UCLA Newsroom

    February 01, 2018
    Joan Harmon

    Media Contact

    John McDonald
    310-880-5332
    mcdonald@gseis.ucla.edu

    1
    Julie Flapan, left, and Jane Margolis say that becoming digitally literate should be required for everyone.

    Jane Margolis, senior researcher at UCLA’s Center X, brings her firsthand experience of inequities in a technical field to her work on bringing computer science education to all students. A summer job as a telephone operator shortly after college led her to become one of the first female telephone installers for Pacific Telephone and Telegraph in the 1970s. She went on to Harvard’s Graduate School of Education where she studied gender socialization and gender, race and inequities in education.

    Margolis emphasizes that her work around computer science has always been about inequality and how fields become segregated. As a researcher at Carnegie Mellon University in the mid-1990s, she was asked to conduct a research study on the lack of female students in what was one of the top computer science departments in the nation. Her findings resulted in her first book, “Unlocking the Clubhouse: Women in Computing,” which she co-wrote with Allan Fisher. Margolis’ work led to more research funded by the National Science Foundation, on why so few African-Americans, Latinos and females were learning computer science in Los Angeles public high schools. The findings revealed the disparities in learning opportunities that fell along race and socio-economic lines, resulting in her second book, “Stuck in the Shallow End: Education, Race, and Computing,” with she authored along with Rachel Estrella, Joanna Goode, Jennifer Jellison Holme and Kim Nao.

    In response to the findings, Margolis and colleagues founded the Exploring Computer Science curriculum and teacher professional development program, which is housed within UCLA Center X’s Computer Science Project.

    ECS is now a national initiative in seven of the largest school districts in the nation, including the Los Angeles Unified School District, the second-largest district in the United States, which has 31 schools in the program. In addition to NSF-funded projects, code.org included the Exploring Computer Science curriculum as the core high school course within their district partnerships across the country.

    Margolis, along with fellow researchers and computer science advocates, helped found the Alliance for California Computing Education for Students and Schools, known as ACCESS. UCLA alumna Julie Flapan, who graduated in 2001 with her doctorate in educataional leadership, serves as the director of the UCLA Computer Science Project and is also the executive director of ACCESS.

    The mission of ECS is to democratize K–12 computer science knowledge and to increase and enhance computer science learning opportunities for underrepresented students, specifically African-American students, Latina and Latino students and females in underserved schools. The ECS program includes professional development for teachers encompassing inquiry, equity and computer science content. The culturally responsive curriculum and teacher education includes an examination of the stereotypes of students who can learn computer science and recommendations of policy change that can institutionalize computer science learning, particularly in schools with high numbers of students of color.

    “Computer science education has been involved in the production and reproduction of inequality, and we are dedicated to changing that,” Margolis said.

    In early 2017, Margolis and Flapan published a commentary in Education Week titled, Stop Scapegoating, Start Educating, that highlighted the need for teachers, schools and families to prepare all students with computer science education, not only for participation in the 21st century job market, but also to empower students to take part in social and political systems in the United States.

    “When students in underserved schools are denied access, experience and role models in computing, they are left further behind,” Flapan and Margolis wrote. “Only 13 percent of AP computer science test takers identified as African-American or Latino, while these students made up more than 24 percent of test takers across all AP exams in 2015. Ensuring access for all students to this foundational knowledge is important preparation for college, careers and civic participation. Becoming digitally literate, critical and constructive thinkers about how to use technology responsibly should be required learning for everyone.”

    With this year’s release of an updated edition of “Stuck in the Shallow End,” Ed and IS magazine [where this story originally appeared] spoke with Flapan and Margolis — who in 2016 was selected by President Barack Obama as a White House Champion of Change. They discussed why their work focuses on equity in computer science and how computing knowledge beyond consumerism can prepare today’s students for college, careers and civic participation.

    How do you ensure that all students have access to high quality computer science?

    Julie Flapan: We bring educational theory about equity into the world of computer science education and are working on parallel tracks to increase demand at the local level for CS in our schools, while also working at the state level to ensure equitable access to teaching and learning opportunities. This includes expanding the pool of teachers who can teach high quality computer science by providing professional development in equity and curriculum. One of the pillars of [the Exploring Computer Science program] is that teachers have intensive preparation to teach the curriculum, which includes research-based culturally responsive pedagogy.

    How has your partnership with LAUSD informed your statewide advocacy?

    Jane Margolis: Our experience with implementing ECS in local districts provides research-based evidence as we scale up computer science statewide. Our efforts to ensure access to high-quality computer science are informed by this research as we insist that equity and inquiry must be integrated with meaningful computer science content.

    Flapan: ACCESS promotes public engagement to build the political will to support opportunities for teaching and learning computer science for all kids. We’re always asking the tough questions about the potential unintended consequences of well-intentioned proposals, and what research and experiences we can provide to help education leaders and policymakers make more informed decisions to benefit all California’s students, especially those who are underrepresented.

    With the growing demand for CS education, where will the teachers come from?

    Flapan: Most people are surprised to learn that there is no single subject CS certification for teachers. ACCESS is working to expand the pool of qualified teachers by updating a computer science supplementary authorization that will allow interested teachers from a variety of subjects to teach computer science.

    Margolis: Our initiatives are all dependent on teachers being active proponents in broadening participation and challenging the underrepresentation that has persisted in this field. There is also a need to bring computer science education into teacher preparation programs in graduate schools of education nationwide. We, along with other people, are working on this.

    Flapan: Computer science is not just about learning how to use the computer, or even just programming. Computer science is really about deeper learning — computational thinking, problem solving, design, algorithmic thinking, and creativity that goes into technological innovation. It crosses a broad range of career opportunities and it is important to expose kids to possibilities that they may not even know exist.

    Can you talk more about the new CSforAll movement?

    Flapan: Computer science is now on the national education scene and has become part of a broader CSforAll movement which was supported by the Obama administration. Many cities, states and large school districts across the country are leading bold initiatives to expand computer science education, led by governors, mayors and other elected officials. There are a handful of national coalitions like Code.org, Expanding Computing Education Pathways, and the CSforAll consortium that are helping states address issues like computer science standards, funding and teacher credentialing issues. All of the states are learning from each other. ACCESS has worked hard the past few years to provide evidence-based research that informs policymakers and other key decisionmakers about the most equitable and effective strategies to scale up computer science. We are working in partnership with a diverse group of organizations and school district leadership on launching a CSforCA campaign to broaden our coalition, build capacity of local leadership and increase communications about the importance of computer science education and ensuring equity and access across California.

    What are the benefits of focusing on a more equitable approach to computer science education?

    Margolis: Computer science has been a highly segregated field. There have been so many strong biases associated with computer science, such as it is best suited for white and Asian male students who are assumed to be the “best and the brightest.” But, we have found the “preparatory privilege” of home resources, early access such as going to computer camp or having a tutor, really gives a jump start for a narrow strata of students. People assume that these are the students who have “innate” talent.

    What’s next for the Exploring Computer Science program?

    Margolis We’re at a very critical juncture between our roles as both researchers and program providers. There’s always a tension when an educational reform program scales really fast. We want to make sure there’s an iterative cycle of learning as we scale, keeping equity at the center. We just received NSF funding for the next five years to conduct another wave of research to highlight the experiences and trajectories of students and teachers going through the program. We will also facilitate a national teachers learning community so that we are able to leverage all the learning that is going on among ECS teachers and program developers.

    Flapan: Computer science is now recognized as its own discipline in K–12 and is also getting integrated into other subjects such as math, science and art. Before ECS, there had never been a computer science course that was designed to be culturally responsive and to appeal to all kids with the expressed intent to expand participation among girls and students of color. There are a lot of institutional forces at play that challenge the introduction of a new discipline to the education system, especially with deeply held biases and beliefs around who can be successful in computer science. Our work is centered on making sure that the focus is on equity so that all kids have access to meaningful and sustainable computer science education.

    Margolis: We have to challenge assumptions about who has what it takes to become a computer scientist, and policies that promote computer science for some students and not others. This means educating teachers, school administrators, and kids themselves. All youth need to feel that, “I belong in this field. I’m going to do this and I belong. And, I can accomplish great things with computing that will positively impact the lives of myself, my family, my community, my world.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 2:46 pm on January 12, 2018 Permalink | Reply
    Tags: Bone morphogenetic proteins, Embryonic stem cells, Scientists make cells that enable the sense of touch, UCLA   

    From UCLA Newsroom: “UCLA scientists make cells that enable the sense of touch” 


    UCLA Newsroom

    January 11, 2018
    Sarah C.P. Williams

    1
    Human embryonic stem cell-derived neurons (green) showing nuclei in blue. Left: with retinoic acid added. Right: with retinoic acid and BMP4 added, creating proprioceptive sensory interneurons (pink).

    Researchers at the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA have, for the first time, coaxed human stem cells to become sensory interneurons — the cells that give us our sense of touch. The new protocol could be a step toward stem cell–based therapies to restore sensation in paralyzed people who have lost feeling in parts of their body.

    The study, which was led by Samantha Butler, a UCLA associate professor of neurobiology and member of the Broad Stem Cell Research Center, was published today in the journal Stem Cell Reports.Researchers at the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA have, for the first time, coaxed human stem cells to become sensory interneurons — the cells that give us our sense of touch. The new protocol could be a step toward stem cell–based therapies to restore sensation in paralyzed people who have lost feeling in parts of their body.

    The study, which was led by Samantha Butler, a UCLA associate professor of neurobiology and member of the Broad Stem Cell Research Center, was published today in the journal Stem Cell Reports.

    Sensory interneurons, a class of neurons in the spinal cord, are responsible for relaying information from throughout the body to the central nervous system, which enables the sense of touch. The lack of a sense of touch greatly affects people who are paralyzed. For example, they often cannot feel the touch of another person, and the inability to feel pain leaves them susceptible to burns from inadvertent contact with a hot surface.

    “The field has for a long time focused on making people walk again,” said Butler, the study’s senior author. “‘Making people feel again doesn’t have quite the same ring. But to walk, you need to be able to feel and to sense your body in space; the two processes really go hand in glove.”

    In a separate study, published in September by the journal eLife, Butler and her colleagues discovered how signals from a family of proteins called bone morphogenetic proteins, or BMPs, influence the development of sensory interneurons in chicken embryos. The Stem Cell Reports research applies those findings to human stem cells in the lab.

    When the researchers added a specific bone morphogenetic protein called BMP4, as well as another signaling molecule called retinoic acid, to human embryonic stem cells, they got a mixture of two types of sensory interneurons. DI1 sensory interneurons give people proprioception — a sense of where their body is in space — and dI3 sensory interneurons enable them to feel a sense of pressure.

    The researchers found the identical mixture of sensory interneurons developed when they added the same signaling molecules to induced pluripotent stem cells, which are produced by reprogramming a patient’s own mature cells such as skin cells. This reprogramming method creates stem cells that can create any cell type while also maintaining the genetic code of the person they originated from. The ability to create sensory interneurons with a patient’s own reprogrammed cells holds significant potential for the creation of a cell-based treatment that restores the sense of touch without immune suppression.

    Butler hopes to be able to create one type of interneuron at a time, which would make it easier to define the separate roles of each cell type and allow scientists to start the process of using these cells in clinical applications for people who are paralyzed. However, her research group has not yet identified how to make stem cells yield entirely dI1 or entirely dI3 cells — perhaps because another signaling pathway is involved, she said.

    The researchers also have yet to determine the specific recipe of growth factors that would coax stem cells to create other types of sensory interneurons.

    The group is currently implanting the new dI1 and dI3 sensory interneurons into the spinal cords of mice to understand whether the cells integrate into the nervous system and become fully functional. This is a critical step toward defining the clinical potential of the cells.

    “This is a long path,” Butler said. “We haven’t solved how to restore touch but we’ve made a major first step by working out some of these protocols to create sensory interneurons.”

    The research was supported by grants from the California Institute for Regenerative Medicine and its Cal State Northridge–UCLA Bridges to Stem Cell Research program, the National Institutes of Health and the UCLA Broad Stem Cell Research Center.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 12:52 pm on December 26, 2017 Permalink | Reply
    Tags: , , , J. William Schopf, John Valley, , , Oldest fossils ever found show life on Earth began before 3.5 billion years ago, SIMS-secondary ion mass spectrometer, Some represent now-extinct bacteria and microbes from a domain of life called Archaea, The study describes 11 microbial specimens from five separate taxa, , UCLA   

    From U Wisconsin Madison and UCLA: “Oldest fossils ever found show life on Earth began before 3.5 billion years ago” 

    U Wisconsin

    University of Wisconsin

    UCLA bloc

    UCLA

    December 18, 2017
    Kelly April Tyrrell
    ktyrrell2@wisc.edu

    1
    Geoscience Professor John Valley, left, and research scientist Kouki Kitajima collaborate in the Wisconsin Secondary Ion Mass Spectrometer Lab (WiscSIMS) in Weeks Hall. Photo: Jeff Miller

    Researchers at UCLA and the University of Wisconsin–Madison have confirmed that microscopic fossils discovered in a nearly 3.5 billion-year-old piece of rock in Western Australia are the oldest fossils ever found and indeed the earliest direct evidence of life on Earth.

    2
    An epoxy mount containing a sliver of a nearly 3.5 billion-year-old rock from the Apex chert deposit in Western Australia is pictured at the Wisconsin Secondary Ion Mass Spectrometer Lab (WiscSIMS) in Weeks Hall. Photo: Jeff Miller

    The study, published Dec. 18, 2017 in the Proceedings of the National Academy of Sciences, was led by J. William Schopf, professor of paleobiology at UCLA, and John W. Valley, professor of geoscience at the University of Wisconsin–Madison. The research relied on new technology and scientific expertise developed by researchers in the UW–Madison WiscSIMS Laboratory.

    4
    J. William Schopf, U Wisconsin Madison

    5
    John Valley, UCLA

    2
    An example of one of the microfossils discovered in a sample of rock recovered from the Apex Chert. A new study used sophisticated chemical analysis to confirm the microscopic structures found in the rock are biological. Courtesy of J. William Schopf

    The study describes 11 microbial specimens from five separate taxa, linking their morphologies to chemical signatures that are characteristic of life. Some represent now-extinct bacteria and microbes from a domain of life called Archaea, while others are similar to microbial species still found today. The findings also suggest how each may have survived on an oxygen-free planet.

    The microfossils — so called because they are not evident to the naked eye — were first described in the journal Science in 1993 by Schopf and his team, which identified them based largely on the fossils’ unique, cylindrical and filamentous shapes. Schopf, director of UCLA’s Center for the Study of Evolution and the Origin of Life, published further supporting evidence of their biological identities in 2002.

    He collected the rock in which the fossils were found in 1982 from the Apex chert deposit of Western Australia, one of the few places on the planet where geological evidence of early Earth has been preserved, largely because it has not been subjected to geological processes that would have altered it, like burial and extreme heating due to plate-tectonic activity.

    But Schopf’s earlier interpretations have been disputed. Critics argued they are just odd minerals that only look like biological specimens. However, Valley says, the new findings put these doubts to rest; the microfossils are indeed biological.

    “I think it’s settled,” he says.

    Using a secondary ion mass spectrometer (SIMS) at UW–Madison called IMS 1280 — one of just a handful of such instruments in the world — Valley and his team, including department geoscientists Kouki Kitajima and Michael Spicuzza, were able to separate the carbon composing each fossil into its constituent isotopes and measure their ratios.

    Isotopes are different versions of the same chemical element that vary in their masses. Different organic substances — whether in rock, microbe or animal ­— contain characteristic ratios of their stable carbon isotopes.

    Using SIMS, Valley’s team was able to tease apart the carbon-12 from the carbon-13 within each fossil and measure the ratio of the two compared to a known carbon isotope standard and a fossil-less section of the rock in which they were found.

    “The differences in carbon isotope ratios correlate with their shapes,” Valley says. “If they’re not biological there is no reason for such a correlation. Their C-13-to-C-12 ratios are characteristic of biology and metabolic function.”

    Based on this information, the researchers were also able to assign identities and likely physiological behaviors to the fossils locked inside the rock, Valley says. The results show that “these are a primitive, but diverse group of organisms,” says Schopf.

    The team identified a complex group of microbes: phototrophic bacteria that would have relied on the sun to produce energy, Archaea that produced methane, and gammaproteobacteria that consumed methane, a gas believed to be an important constituent of Earth’s early atmosphere before oxygen was present.

    3
    UW–Madison geoscience researchers on a 2010 field trip to the Apex Chert, a rock formation in western Australia that is among the oldest and best-preserved rock deposits in the world. Courtesy of John Valley

    It took Valley’s team nearly 10 years to develop the processes to accurately analyze the microfossils — fossils this old and rare have never been subjected to SIMS analysis before. The study builds on earlier achievements at WiscSIMS to modify the SIMS instrument, to develop protocols for sample preparation and analysis, and to calibrate necessary standards to match as closely as possible the hydrocarbon content to the samples of interest.

    In preparation for SIMS analysis, the team needed to painstakingly grind the original sample down as slowly as possible to expose the delicate fossils themselves — all suspended at different levels within the rock and encased in a hard layer of quartz — without actually destroying them. Spicuzza describes making countless trips up and down the stairs in the department as geoscience technician Brian Hess ground and polished each microfossil in the sample, one micrometer at a time.

    Each microfossil is about 10 micrometers wide; eight of them could fit along the width of a human hair.

    Valley and Schopf are part of the Wisconsin Astrobiology Research Consortium, funded by the NASA Astrobiology Institute, which exists to study and understand the origins, the future and the nature of life on Earth and throughout the universe.

    Studies such as this one, Schopf says, indicate life could be common throughout the universe. But importantly, here on Earth, because several different types of microbes were shown to be already present by 3.5 billion years ago, it tells us that “life had to have begun substantially earlier — nobody knows how much earlier — and confirms it is not difficult for primitive life to form and to evolve into more advanced microorganisms,” says Schopf.

    Earlier studies by Valley and his team, dating to 2001, have shown that liquid water oceans existed on Earth as early as 4.3 billion years ago, more than 800 million years before the fossils of the present study would have been alive, and just 250 million years after the Earth formed.

    “We have no direct evidence that life existed 4.3 billion years ago but there is no reason why it couldn’t have,” says Valley. “This is something we all would like to find out.”

    UW–Madison has a legacy of pushing back the accepted dates of early life on Earth. In 1953, the late Stanley Tyler, a geologist at the university who passed away in 1963 at the age of 57, was the first person to discover microfossils in Precambrian rocks. This pushed the origins of life back more than a billion years, from 540 million to 1.8 billion years ago.

    “People are really interested in when life on Earth first emerged,” Valley says. “This study was 10 times more time-consuming and more difficult than I first imagined, but it came to fruition because of many dedicated people who have been excited about this since day one … I think a lot more microfossil analyses will be made on samples of Earth and possibly from other planetary bodies.”

    See the full U Wisconsin article here .
    See the full uCLA article by Stuart Wolpert here.
    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

    In achievement and prestige, the University of Wisconsin–Madison has long been recognized as one of America’s great universities. A public, land-grant institution, UW–Madison offers a complete spectrum of liberal arts studies, professional programs and student activities. Spanning 936 acres along the southern shore of Lake Mendota, the campus is located in the city of Madison.

     
    • stewarthoughblog 1:44 am on December 27, 2017 Permalink | Reply

      Schopf’s wishful speculation that what was discovered indicates life must be common is intellectually insulting with his failure that somehow live emerged rapidly, which strains the slow, methodical Darwinian theory of how life developed, given the relative complexity of the microorganisms. This is a wonderful discovery, but does nothing to solve the origin of life and raises serious questions about the power of naturalism to explain the origin of life as well as the rapid development of higher order complex organisms.

      The only extraterrestrial organisms that will be found will be those of Earth origin.

      Like

  • richardmitnick 9:53 am on December 6, 2017 Permalink | Reply
    Tags: Acoustic Doppler Current Profiler, , At least half of sea level rise from Greenland is from melting ice, , , Extreme fieldwork drones and climate modeling yield new insights about Greenland’s melting ice sheet, , UCLA   

    From UCLA Newsroom: “Extreme fieldwork, drones, climate modeling yield new insights about Greenland’s melting ice sheet” 


    UCLA Newsroom

    December 05, 2017
    Jessica Wolf

    1
    A UCLA-led team was the first to measure Greenland’s melting glaciers from the top of the ice sheet. Their discoveries could help scientists better predict sea level rise. Matthew Cooper

    A new UCLA-led study reinforces the importance of collaboration in assessing the effects of climate change.

    The research, published today in the journal Proceedings of the National Academy of Sciences, offers new insights about previously unknown factors affecting Greenland’s melting ice sheet, and it could ultimately help scientists more accurately predict how the phenomenon could cause sea levels to rise.

    Greenland is the single largest melting ice sheet in terms of meltwater runoff contributing to rising sea levels — and at least half of sea level rise from Greenland is from melting ice, said Laurence C. Smith, a UCLA professor of geography. (That’s even more than the amount caused by ice calving, when large blocks of ice separate from the ice sheet, forming icebergs, which eventually melt into the sea.)

    Since 2012, a team led by Smith has visited Greenland’s ice sheet several times, using satellites, drones and sophisticated sensors to track flow rates of meltwater rivers atop the glaciers, and to map their watersheds, which include the surface areas between the rivers.

    In 2015, Smith and a group of UCLA graduate students and collaborators focused on a 27-square-mile watershed, and they discovered an important process that had previously been left out of climate-model calculations. Some of the meltwater from the lakes and rivers atop the region’s glaciers, which end in large sinkholes called “moulins” and barrel down through the glacier, is being stored and trapped on top of the glacier inside a low-density, porous “rotten ice.”

    “Ours is the first independent data-gathering effort to directly measure rates of meltwater runoff from the top of the ice,” Smith said. The team’s research was funded by NASA. “Researchers, including us, have attempted gather information using flows from the edge of the ice, but those measurements are problematic for testing climate models.”

    Smith’s team found a discrepancy between its data and the calculations of meltwater runoff from five climate models. Those models’ estimates were 21 to 58 percent higher than what Smith’s team measured on the ice.

    So Smith invited the scientists who created those models to collaborate with him. Together, they checked real-time statistics from weather stations on the ice to confirm that the data in the climate models were correct — and they found the models’ calculations were accurate. Which meant that the meltwater’s journey over the ice surface was more complex than previously imagined: The scientists recognized that before the water passes through the ice via moulins, it can pool, sit indefinitely or refreeze in porous ice at the surface, Smith said.

    “After eliminating all other possibilities, we deduced that the disagreement in our data is because of sunlight penetrating into the ice, causing subsurface melting and meltwater storage,” said Dirk van As, a co-author of the study and a senior researcher at the Geological Survey of Denmark and Greenland. “And now we know this is happening in the higher reaches of the bare ice zone that cover large regions of the ice sheet.

    “We now know that calculation of meltwater retention in porous ice should be included somehow,” he said.

    To measure river discharge on the ice, Smith and his team adapted a technique normally used on land. Working in shifts, they collected data hourly, around the clock, for three days in July 2015, braving the cold, wind and 20 hours a day of blazing sunshine. The researchers used safety gear to anchor themselves to the ice and protect themselves from the swift-moving water flowing into dangerous moulins, where surface water plummets into the ice sheet interior.

    Among the many logistical challenges was determining how to set up equipment to measure river flow in a way that researchers didn’t need to be positioned on both sides of a river.

    “Unless you have a helicopter, you can’t station people on both sides of a large river on top of the ice,” said Lincoln Pitcher, a UCLA doctoral student in geography, who figured out a way to keep sensors in place after trial and error on land and ice. They needed to come up with a stable and strong system that would stay in place even though the ice surface around them was melting.

    Study co-author, Asa Rennermalm, professor of geography at Rutgers University-New Brunswick was part of the field team.

    “We used a device called an Acoustic Doppler Current Profiler, which tracks discharge based on sound,” she said. “We attached it to a floatable platform, and then attached that to ropes, which were attached to poles on either side of the ice river. We moved the platform back and forth across the river every hour for 72 hours. No one has ever done that before on the Greenland ice sheet.”

    Van As said the project proved that combining expertise from multiple disciplines — among them meteorology, oceanography and hydrology (the study of the properties and movement of water over land) — is essential for fully understanding how glaciers and ice sheets respond to the climate system.

    “It is important that hydrologists like Larry bring their extensive knowledge into the field of glaciology, using approaches that are new to our discipline,” he said.

    In general, glaciologists are not accustomed to thinking about watersheds on top of the ice, Smith said. The irregularities those watersheds impart on the timing and amount of meltwater penetrating the ice are not currently considered in geophysical models of “ice dynamics,” meaning the speed and spatial pattern of sliding glacial ice as it moves toward the sea.

    “We’re taking the very mature field of land surface hydrology, which deals with river flow and watersheds on land, and applying it to the ice sheet, which has typically been the scientific domain of solid-ice geophysics,” he said. “We have to borrow from hydrology because the ice surface is becoming more of a hydrologic phenomenon. And we can take these tools from another discipline and apply them and actually have a conceptual breakthrough.”

    Smith and his team now are working on a study based on data from a 2016 trip to Greenland, when they spent a week tracking watersheds and digging into the rotten ice.

    Led by UCLA graduate student Matthew Cooper, the researchers are attempting to better explain how rotten ice traps water. They have tracked the rotten ice to a depth of nearly 3 feet below the surface — a finding that could help scientists who develop climate models to better understand how ice sheets are losing mass.

    Part of Smith’s mission in Greenland is empowering a new generation of hydrologists who are eager to join the front lines of tracking global climate change.

    “Climate change is not remote news for me anymore,” said Kang Yang, a former UCLA postdoctoral scholar, who was part of the field team for this study. Now a professor at China’s Nanjing University, Yang will continue to work with Smith on mapping the rivers on Greenland’s ice sheet.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
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