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  • richardmitnick 9:14 am on July 3, 2019 Permalink | Reply
    Tags: , , Cable bacteria grow to astonishing densities. One square inch of sediment may contain as much as eight miles of cables., , Discoveries like these raised the possibility that other bacteria might be dabbling in electricity., Electroactive bacteria, Geobacter can also plug into other species of microbes., Geobacter metallireducens feeds on carbon compounds, Geobacter transfers its electrons to iron oxide or rust., NYT, , The microbe responded by sprouting hairlike growths   

    From The New York Times: “Wired Bacteria Form Nature’s Power Grid: ‘We Have an Electric Planet’ “ 

    New York Times

    From The New York Times

    July 1, 2019
    Carl Zimmer

    Electroactive bacteria were running current through “wires” long before humans learned the trick.

    1
    Gordon Studer

    At three o’clock in the afternoon on September 4, 1882, the electrical age began. The Edison Illuminating Company switched on its Pearl Street power plant, and a network of copper wires came alive, delivering current to a few dozen buildings in the surrounding neighborhood.

    One of those buildings housed this newspaper. As night fell, reporters at The New York Times gloried in the steady illumination thrown off by Thomas Edison’s electric lamps. “The light was soft, mellow, and grateful to the eye, and it seemed almost like writing by daylight,” they reported in an article the following day.

    But nature invented the electrical grid first, it turns out. Even in 1882, thousands of miles of wires were already installed in the ground in the New York region — in meadows, in salt marshes, in muddy river bottoms. They were built by microbes, which used them to shuttle electricity.

    Electroactive bacteria were unknown to science until a couple of decades ago. But now that scientists know what to look for, they’re finding this natural electricity across much of the world, even on the ocean floor. It alters entire ecosystems, and may help control the chemistry of the Earth.
    What on Earth Is Going On?

    “Not to sound too crazy, but we have an electric planet,” said John Stolz, a microbiologist at Duquesne University in Pittsburgh.

    In the mid-1980s, Dr. Stolz was helping to study a baffling microbe fished out of the Potomac River by his colleague Derek Lovley. The microbe, Geobacter metallireducens, had a bizarre metabolism. “It took me six months to figure out how to grow it in the lab,” said Dr. Lovley, now a microbiologist at the University of Massachusetts at Amherst.

    Like us, Geobacter feed on carbon compounds. As our cells break down these compounds to generate energy, they strip off free electrons and transfer them to oxygen atoms, producing water molecules. Geobacter couldn’t use oxygen, however, because it lived at the bottom of the Potomac, where the element was in short supply.

    Instead, Geobacter transfers its electrons to iron oxide, or rust, Dr. Lovley and his colleagues discovered. The process helps turn rust into another iron compound, called magnetite.

    The finding left the scientists with a puzzle. We humans draw oxygen into our cells to utilize it, but Geobacter does not import rust. So the microbe must somehow get the electrons out of its cell body and attach them to rust particles. How?

    A real live wire

    The researchers struggled for years to find the answer. Dr. Stolz eventually turned to other microbes to study. But Dr. Lovley soldiered on. Over the years, he and his colleagues have come across Geobacter in many places far beyond the Potomac. They’ve even encountered the bacteria in oil drilled from deep underground. “It’s basically found everywhere,” Dr. Lovley said.

    In the early 2000s, Dr. Lovley’s team discovered that Geobacter could sense rust in its neighborhood. The microbe responded by sprouting hairlike growths.

    Maybe each of those growths, known as a pilus, was actually a wire that latched onto the rust, Dr. Lovley thought. Electrons could flow from the bacterium down the wire to the receptive rust. “It seemed like a wild idea at the time,” Dr. Lovley said.

    But he and his team found several clues suggesting that the pilus is indeed a living wire. In one experiment, when Geobacter was prevented from making pili, the bacteria couldn’t turn rust to magnetite. In another, Dr. Lovley and his colleagues plucked pili from the bacteria and touched them with an electrified probe. The current swiftly shot down the length of the hairs.

    Subsequent research revealed that Geobacter can deploy its wires in different ways to make a living. Not only can it plug directly into rust, it can also plug into other species of microbes.

    The partners of Geobacter welcome the incoming flow of electrons. They use the current to power their own chemical reactions, which convert carbon dioxide into methane.

    2
    Gordon Studer

    Discoveries like these raised the possibility that other bacteria might be dabbling in electricity. And in recent years, microbiologists have discovered a number of species that do.

    “When people are able to dig down at the molecular level, we’re finding major differences in strategy,” said Jeff Gralnick of the University of Minnesota. “Microbes have solved this issue in several different ways.”

    In the early 2000s, a Danish microbiologist named Lars Peter Nielsen discovered a very different way to build a microbial wire. He dug up some mud from the Bay of Aarhus and brought it to his lab. Putting probes in the mud, he observed the chemical reactions carried out by its microbes.

    “It developed in a very weird direction,” Dr. Nielsen recalled.

    At the base of the mud, Dr. Nielsen observed a buildup of a foul-smelling gas called hydrogen sulfide. That alone was not surprising — microbes in oxygen-free depths can produce huge amounts of hydrogen sulfide. Normally, the gas rises the surface, where oxygen-breathing bacteria can break most of it down.

    But the hydrogen sulfide in the Aarhus mud never made it to the surface. About an inch below the top of the mud, it disappeared; something was destroying it along the way.

    After weeks of perplexity, Dr. Nielsen woke up one night with an idea. If the bacteria at the bottom of the mud broke hydrogen sulfide without oxygen, they would build up extra electrons. This reaction could only take place if they could get rid of the electrons. Maybe they were delivering them to bacteria at the surface.

    “I imagined it could be electric wires, and I could explain all of this,” he said.

    So Dr. Nielsen and his colleagues looked for wires, and they found them. But the wires in the Aarhus mud were unlike anything previously discovered.

    Each wire runs vertically up through the mud, measuring up to two inches in length. And each one is made up of thousands of cells stacked on top of each other like a tower of coins. The cells build a protein sleeve around themselves that conducts electricity.

    As the bacteria at the bottom break down hydrogen sulfide, they release electrons, which flow upward along the “cable bacteria” to the surface. There, other bacteria — the same kind as on the bottom, but employing a different metabolic reaction — use the electrons to combine oxygen and hydrogen and make water.

    Cable bacteria are not unique to Aarhus, it turns out. Dr. Nielsen and other researchers have found them — at least six species so far — in many places around the world, including tidal pools, mud flats, fjords, salt marshes, mangroves and sea grass beds.

    And cable bacteria grow to astonishing densities. One square inch of sediment may contain as much as eight miles of cables. Dr. Nielsen eventually learned to spot cable bacteria with the naked eye. Their wires look like spider silk reflecting the sun.

    Electroactive microbes are so abundant, in fact, that researchers now suspect that they have a profound impact on the planet. The bioelectric currents may convert minerals from one form to another, for instance, fostering the growth of a diversity of other species. Some researchers have speculated that electroactive microbes may help regulate the chemistry of both the oceans and the atmosphere.

    “To me, it’s a strong reminder of how ready we are to ignore things we cannot imagine,” Dr. Nielsen said.

    Electroactive bacteria for hire

    Much about these microbes remains murky, and subject to debate. In April, Nikhil S. Malvankar, a physicist at Yale University, and his colleagues challenged Dr. Lovley’s finding that Geobacter use pili as wires.

    Their research indicates that bacteria use a different structure to pump electrons. It’s a wire built from building blocks called cytochromes. Individual cytochromes are important for moving electrons around inside cells. But until now no one knew they could be stacked into a conductive wire.

    “There never had been a material like this before,” Dr. Malvankar said.

    Sarah Glaven, a research biologist at the United States Naval Research Laboratory who was not involved in the new study, said she found it compelling. “Totally believe it,” she said. “The question is, is it just part of the puzzle?”

    It’s possible that Geobacter uses both structures to move electrons, Dr. Glaven said. Or maybe one serves a different function, and just happens to conduct electricity in the hands of a scientist.

    The answers to such questions matter deeply to scientists, who are tinkering with electroactive bacteria to develop new kinds of technology.

    At Cornell University, Buz Barstow and his colleagues are investigating the possibility of wiring bacteria to solar panels. The panels would capture sunlight and generate a stream of electrons. The electrons would stream down microbial wires to a species of bacteria called Shewanella, which would use the energy to convert sugar into fuel.

    It’s still a distant dream. For now, Dr. Barstow is trying to work out the basic biology by which Shewanella moves electrons from its wires to the molecules it uses for its metabolism. But he is so taken with the elegance of electroactive bacteria that he figures it’s worth a shot. “You’re talking to someone who has drunk the Kool-Aid,” he said.

    Other researchers are looking into using these filaments as sensors. For instance, a wristband with embedded wires might monitor people’s health by delivering electric current when it detects chemical changes in sweat. Dr. Lovley and his colleagues are genetically engineering Geobacter to add molecular hooks to their pili, so that they snag certain molecules.

    Among the many advantages that living wires may have is that they’d be easier on the environment than the man-made kind. “It takes a lot of energy and nasty chemicals to make a lot of those electronic materials, and then none of them are biodegradable,” Dr. Lovley said.

    Bacteria, by contrast, can build wires from little more than sugar. And when it comes time to throw wires away, they become food for other microbes.

    Dr. Nielsen, who now directs the Center for Electromicrobiology at the University of Aarhus in Denmark, said that he is avoiding the technology rush for now. There is still too much to learn about the microbes themselves. “Once we find out what these wires are made from and how they work, a lot of potential applications may show up,” he said.

    See the full article here .

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  • richardmitnick 3:04 pm on June 26, 2019 Permalink | Reply
    Tags: , , , , NYT, Vulcanism om the Moon Io   

    From The New York Times: “This World Is a Simmering Hellscape. They’ve Been Watching Its Explosions.” 

    New York Times

    From The New York Times

    June 26, 2019
    Joshua Sokol

    1
    A volcanic eruption on Jupiter’s moon Io, seen by NASA’s Galileo spacecraft. Credit NASA

    On hundreds of clear nights over the last five years, giant telescopes on a dormant, sacred volcano in Hawaii have trained their gaze across space toward active volcanoes on a simmering hellscape of a moon that orbits Jupiter. It’s called Io.

    2
    NASA’s Galileo spacecraft acquired its highest resolution images of Jupiter’s moon Io on 3 July 1999 during its closest pass to Io since orbit insertion in late 1995. This color mosaic uses the near-infrared, green and violet filters (slightly more than the visible range) of the spacecraft’s camera and approximates what the human eye would see. Most of Io’s surface has pastel colors, punctuated by black, brown, green, orange, and red units near the active volcanic centers. A false color version of the mosaic has been created to enhance the contrast of the color variations.

    NASA/Galileo 1989-2003

    “You just see so many volcanoes. It’s incredible,” said Katherine de Kleer, a planetary scientist at Caltech who has led the effort.

    Last week, Dr. de Kleer’s team released their full five-year record of Io’s volcanic activity in The Astronomical Journal. Their data show a pimple-ridden surface roiling with eruptions. Some hot spots glow continuously, while other areas flare up, then die back down.

    The researchers’ hope is that other planetary scientists may be able to glimpse or dig into the underlying rhythms of this world, the most volcanically active body in the solar system.

    Witnessing eruptions on a faraway moon used to require more of a trek. Forty years ago, the Voyager probes first spotted volcanoes on Io, a body that scientists expected would look dead and cratered. Instead, it turned out to be pockmarked with oozing hot spots.

    NASA/Voyager 1

    The Galileo spacecraft took another close look starting in the 1990s, and the Juno mission, currently at Jupiter, glanced at a volcanic plume sprouting from Io’s surface last December.

    NASA/Juno

    But these short visits didn’t let scientists study whether Io’s drumbeat of eruptions follows underlying patterns.

    Io’s volcanoes are thought to be fueled by tidal heating, a stretching-and-squeezing process whereby gravitational forces treat the inside of Io like a stress ball as the moon swings around Jupiter. That same process might be the main energy source driving geologic activity on many small moons and planets throughout the galaxy.

    Io’s eruptions are also thought to blast material into space, wafting plasma through the entire Jupiter system, where it swirls along magnetic field lines. Some ejecta from volcanoes even fall back on the surfaces of other moons like Europa, a prime candidate in the search for life.

    Hoping to understand them better, Earth-based astronomers have long tried to track where and when Io’s individual volcanoes flare up, then fade. One team including Julie Rathbun of the Planetary Science Institute in Tucson, Ariz., has monitored Io’s brightest volcanoes over two decades. But Dr. de Kleer’s survey captures far more detail.

    “Her observations blow ours out of the water,” Dr. Rathbun says.

    One pattern has already emerged. The moon’s trailing hemisphere — if you think of Io as a car driving in a circle around Jupiter, it’s the back windshield — seems to host far more bright, temporary eruptions than the other side of the moon.

    This could be the result of Io’s crust differing from hemisphere to hemisphere, or because a single big eruption on the trailing hemisphere has triggered subsequent blasts. (Or, it could still be just a fluke in the data.)

    Another suggestive pattern comes from Loki Patera, Io’s single most powerful volcano and a gaping window to the interior of the moon.

    It brightens and fades about every 460 or 480 days, according to an analysis published by Dr. de Kleer and colleagues in the Geophysical Research Letters in May. If Loki Patera continues to wax and wane into the next few years as predicted, that time frame would match other cyclical variations in how Io orbits Jupiter — providing a suggestive link between changing tides exerted by Jupiter and the ebbs and flows of surface volcanoes.

    Back on Earth, Dr. Rathbun said, she and other planetary scientists are proposing a NASA probe that would study Io’s volcanism up close. But she stressed the value of long-term monitoring.

    “I really feel like we need to keep watching this. Five, ten years in the life of a volcano is nothing.”

    See the full article here .

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  • richardmitnick 12:37 pm on June 23, 2019 Permalink | Reply
    Tags: 5 currently useful and operating telescopes to be removed from Mauna Kea, , , , , NYT, TMT work begins on Mauna Kea   

    From The New York Times: “In Hawaii, Construction to Begin on Disputed Telescope Project” 

    New York Times

    From The New York Times

    June 20, 2019
    Dennis Overbye

    TMT-Thirty Meter Telescope, proposed and now approved for Mauna Kea, Hawaii, USA4,207 m (13,802 ft) above sea level

    Gov. David Ige of Hawaii announced on Thursday that a “notice to proceed” had been issued for construction of a giant, long-contested telescope on Mauna Kea, the volcano on the Big Island that 13 major telescopes already call home. Construction could start as soon as July.

    Such an announcement has been anxiously awaited both by astronomers and by Hawaiian cultural activists since last year, when Hawaii’s Supreme Court restored the telescope’s building permit. As part of the deal, five telescopes currently operating on Mauna Kea will be shut down and their sites restored to their original condition.

    “We are all stewards of Mauna Kea,” Governor Ige said. He pledged to respect the rights and cultural traditions of the Hawaiian people, including the freedom to speak out against the telescope.

    He asked that further debate happen away from the mountain, where steep roads and limited water, oxygen and medical services pose a safety risk. As he spoke, arguments were already breaking out on Twitter and Facebook.

    “This decision of the Hawaiian Supreme Court is the law of the land, and it should be respected,” he said.

    The announcement was another skirmish, surely not the last, for control of the volcano’s petrified lava slopes and the sky overhead. The Thirty Meter Telescope would be the largest in the Northern Hemisphere. Hawaiian activists have long opposed it, contending that decades of telescope-building on Mauna Kea have polluted the mountain. In 2014, protesters disrupted a groundbreaking ceremony and blocked work vehicles from accessing the mountain.

    Mauna Kea is considered “ceded land” held in trust for the Hawaiian people, and some Hawaiians have argued that the spate of telescope construction atop the mountain has interfered with cultural and religious practices.

    The Thirty Meter Telescope would be built by an international collaboration called the TMT International Observatory. The project, which involves the University of California and the California Institute of Technology as well as Japan, China, India and Canada, is expected to cost $2 billion.

    In December 2015, the state’s Supreme Court invalidated a previous construction permit, on the grounds that the opponents had been deprived of due process because a state board had granted the permit before the opponents could be heard in a contested case hearing. The court awarded a new permit last year.

    At the time, astronomers with the project said they would build the telescope in the Canary Islands if denied in Hawaii.

    On Wednesday night, in a precursor to Thursday’s announcement, state authorities dismantled an assortment of structures that had been constructed on Mauna Kea by protesters.

    The structures included a pair of shacks called “hales,” one located across from a visitor center halfway up the mountain, where protests had been staged, and another at the base of the mountain that activists were using as a checkpoint.

    Also dismantled were two small stone monuments, or “ahus” — one on the road leading to the telescope site, the other in the middle of the site, according to a spokesman for the TMT project. They were built only recently, without a permit, and so were deemed by the court to have no historical value.

    But Kealoha Pisciotta, a leader of the opposition, called the dismantling a “desecration” and “a hostile and racist act,” in an email. “They call these Religious structures illegal structures but our rights are constitutionally protected and the right specifically protected is our right to ‘continue’ our practice,” she wrote.

    See the full article here .

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  • richardmitnick 1:57 pm on April 13, 2019 Permalink | Reply
    Tags: , , , , EHT reveals image of Messier 87, Katie Bouman-Harvard Smithsonian Observatory for Astrophysics-headed to Caltech, NYT,   

    From The New York Times: Women in STEM-“How Katie Bouman Accidentally Became the Face of the Black Hole Project” 

    New York Times

    From The New York Times

    April 11, 2019
    Sarah Mervosh

    As the first-ever picture of a black hole was unveiled this week, another image began making its way around the internet: a photo of a young scientist, clasping her hands over her face and reacting with glee to an image of an orange ring of light, circling a deep, dark abyss.

    The first image of a black hole, Messier 87 Credit Event Horizon Telescope Collaboration, via NSF 4.10.19

    It was a photo too good not to share. The scientist, Katie Bouman, a postdoctoral fellow who contributed to the project, became an instant hero for women and girls in STEM, a welcome symbol in a world hungry for representation.

    Katie Bouman-Harvard Smithsonian Astrophysical Observatory. Headed to Caltech.

    Public figures from Washington to Hollywood learned her name. And some advocates, familiar with how history can write over the contributions of women, quickly moved to make sure she received the recognition she deserved.

    Katie Bouman of Harvard Smithsonian Observatory for Astrophysics, headed to Caltech, with EHT hard drives from Messier 87

    In their eagerness to celebrate her, however, many nonscientists on social media overstated her role in what was a group effort by hundreds of people, creating an exaggerated impression as the photo was shared and reshared.

    As Dr. Bouman herself was quick to point out, she was by no means solely responsible for the discovery, which was a result of a worldwide collaboration among scientists who worked together to create the image from a network of radio antennas.

    The project, led by Shep Doeleman, an astronomer at the Harvard-Smithsonian Center for Astrophysics, was the work of more than 200 researchers. About 40 of them were women, according to Harvard’s Black Hole Initiative.

    “There are women involved in every single step of this amazing project,” said Sara Issaoun, 24, a graduate student at Radboud University in the Netherlands who worked on the research. “As a woman in STEM myself, it’s good to have role models out there who young girls and young boys can look up to.”

    But Ms. Issaoun warned against a “lone-wolf success” narrative. “The diversity and group effort and the breadth of our collaboration, I think, is worth celebration,” she said.

    To capture the image of a black hole — a mysterious phenomenon long thought to be unseeable — the scientists used eight radio observatories across the globe to observe the galaxy on and off for 10 days in April 2017. Then they embarked on the painstaking effort to process enormous amounts of data and map it into an image.

    Dr. Bouman, who will soon become an assistant professor at the California Institute of Technology, indeed played a significant role in the imaging process, which involved researchers breaking up into teams to map the data and compare and test the images they created.

    While she led the development of an algorithm to take a picture of a black hole, an effort that was the subject of a TED Talk she gave in 2016, her colleagues said that technique was not ultimately used to create this particular image.

    After the burst of publicity spread her smiling face across Twitter, Facebook, Reddit and news sites around the globe, Dr. Bouman did not initially respond to requests for comment Thursday. In a Facebook post, she said: “No one algorithm or person made this image. It required the amazing talent of a team of scientists from around the globe.”

    “It has been truly an honor,” she added, “and I am so lucky to have had the opportunity to work with you all.”

    In a text message late Thursday night, Dr. Bouman said that she had to turn her phone off because she was getting so many messages. “I’m so glad that everyone is as excited as we are and people are finding our story inspirational,’’ she wrote. “However, the spotlight should be on the team and no individual person. Focusing on one person like this helps no one, including me.”

    Other women on the project also celebrated this week as years of hard work were finally made public.

    “Honestly, it was a dream come true,” Sandra Bustamante, a telescope instrumentalist who worked on the project, said in an interview this week.

    Feryal Ozel, an astronomy and astrophysics professor at the University of Arizona who was on the science council for the project, first published a paper on black hole imaging in 2000. She called the unveiling “a sweet moment that’s been a long time in the making.”

    In an interview on Thursday, Dr. Ozel said that it was exciting to see people interested in the role of women in science, but she highlighted the contributions of other women and men. That included one of her male graduate students, who took multiple trips to the South Pole, where one of the telescopes was located.

    “I think giving credit to any single individual — whether this is a woman or man, young or old — harms the collaboration,” she said.

    Penn Sheppard, who works with Girls Inc., an organization that empowers young women and offers after-school programming to support girls learning in science, technology, engineering and math, said that Dr. Bouman’s story resonated in an industry in which women are underrepresented — and in a world in which their scientific contributions have historically gone unacknowledged.

    “It was an opportunity to see an accomplished woman play a significant role, and being acknowledged in that role,” she said. “That’s significant because girls and young boys are starting to see that women are scientists — not just you can be, but you are.”

    Ms. Issaoun said she also wanted to celebrate the success of a diverse collaboration of scientists, but she said she understood why the photo of Dr. Bouman went viral.

    “We love this photo too, because she looks so happy,” said Ms. Issaoun, who said she got shivers when she saw the image of a black hole. “I think her expression really captures how we all felt when we first saw it.”

    See the full article here .

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  • richardmitnick 1:12 pm on April 13, 2019 Permalink | Reply
    Tags: "When a Black Hole Finally Reveals Itself, , It Helps to Have Our Very Own Cosmic Reporter", , NYT   

    From The New York Times: “When a Black Hole Finally Reveals Itself, It Helps to Have Our Very Own Cosmic Reporter” 

    New York Times

    From The New York Times

    April 12, 2019
    Aidan Gardiner

    Astronomers announced Wednesday that they had captured the first image of a black hole. The Times’s Dennis Overbye answers readers’ questions.

    2
    The first image of a black hole, from the galaxy Messier 87.Credit Event Horizon Telescope Collaboration, via National Science Foundation

    1
    Dennis Overbye, cosmic reporter for The New York Times, answering readers’ questions at his desk.Credit Aidan Gardiner/The New York Times

    When radio waves from the depths of a nearby galaxy known as Messier 87 traveled some 55 million light-years to a constellation of telescopes on Earth, revealing to humanity the face of a black hole for the first time, people around the planet paused in wonder.

    Why does it look like a doughnut? How scary is it when two of these things smash into each other? And if light can’t escape a black hole, what are we even looking at?

    Our coverage Wednesday of the first ever image of a black hole, by our cosmic reporter Dennis Overbye, drew a huge response from our readers. Dennis graduated from M.I.T. with a physics degree and was a Pulitzer Prize finalist in 2014 for his coverage for The New York Times of the race to find the Higgs boson. He sat down Thursday with his feet on his desk, beside a photo of the black hole, to answer some of our readers’ questions and respond to their feedback.

    Below are some of the exchanges that he had during an AMA on Reddit and in the comments on his article. They are edited for clarity.

    What does this image really tell us besides black holes are round?

    This is the first look into the central engine that generates the enormous energies put out by quasars, radio galaxies and other so-called active galactic nuclei. The action all starts down at the edge of oblivion, in a maelstrom of hot gas, gravity, magnetic fields and otherworldly pressures. It extends out beyond the far reaches of the galaxy, as jets of radio-wave energy moving at nearly the speed of light; these lobes of radio energy can accompany shock waves capable of blowing the gas out of galaxies or even entire clusters of them, preventing stars from forming. Through these mechanisms, black holes, blowing hot and cold, control the growth and structure of galaxies. It all starts in the accretion disk, the doughnut of doom.

    Why does it look like a “doughnut of doom” and not a sphere?

    When matter falls together into a black hole, or in almost any other situation, it has angular momentum, and takes on the shape of a flattened pancake spinning around the central attraction. Also, the black hole is probably spinning, pulling the disk around in the same direction. We are seeing the disk almost directly face-on, so it looks like a doughnut hole. (From edge-on it would look different.) Bent by gravity, light wraps around the hole on its way to our eyes, so the black hole magnifies and distorts the image of the accretion disk.

    Will we ever get a clearer image of this black hole?

    We will. The key is to observe black holes at shorter and shorter radio wavelengths, which allows more and more detail to be resolved. The latest images were recorded at a wavelength of 1.3 millimeters in the microwave band. The Event Horizon team hopes to go to shorter wavelengths in the future, and to use more antennas, including one in space, which would increase the size of their “virtual telescope” and also increase resolution.

    Do you feel that coverage of the breakthrough minimized the role of Katherine Bouman, a researcher at the Harvard-Smithsonian Center for Astrophysics?

    The issue of the unsung hero or heroine is a big problem, especially in Big Science, which the Event Horizon Telescope is surely part of.

    There were 207 people in the collaboration, according to one of the physicists I talked to that day. I am sure that many crucial contributions and rich anecdotes of behind-the-scenes science got missed.

    In time, these will come out in more thoughtful, longer narratives. On the day of the announcement there was a tsunami of information released at 9 a.m., and a rush to post stories as soon as possible, an unfortunate fact of the internet age.

    What does current science tell us is supposed to happen in the gravitational extremes of a black hole?

    That’s the biggie everybody wants to know. Whatever happens there, it probably is similar to what happened, maybe in reverse, in the Big Bang. Space, time, matter all go away, replaced by what? Some people think the answers might come from string theory, which unites gravity with quantum theory. But for now it remains an untestable, but mathematically elegant, speculation.

    What happens when two black holes collide?

    Such collisions have happened and been recorded by the LIGO gravitational wave observatory.


    They vibrated the space-time continuum like a drum and released as much energy in a fraction of a second as all the stars in the observable universe. The result in each case was an even bigger, blended black hole.

    But outside the event horizon, the gravitational field of a black hole is just like that of a star and it is no more dangerous. Black holes don’t go roaming around looking to swallow you. They only hurt if you touch them, in which case you won’t ever be able to let go. Otherwise they are like any other animal that you would just let go, and mind your own business.

    How is any of this relevant to our day-to-day lives?

    It can certainly provide context to your daily life, but it won’t move the markets. It will, or could, move your soul. However, Einstein, when he invented the sort of trampoline universe described by general relativity, did not dream that it would lead to pocket devices that keep time and tell you precisely where you are on Earth — that is to say, GPS. But they depend crucially on general relativity to tell you where you are. So who knows?

    See the full article here .

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  • richardmitnick 11:15 am on March 18, 2019 Permalink | Reply
    Tags: "Space Is Very Big. Some of Its New Explorers Will Be Tiny", , , , , NASA MarCO cubesats, , NYT   

    From The New York Times: “Space Is Very Big. Some of Its New Explorers Will Be Tiny” 

    New York Times

    From The New York Times

    March 18, 2019
    Shannon Stirone

    The success of NASA’s MarCO mission means that so-called cubesats likely will travel to distant reaches of our solar system.

    NASA JPL MarCO cubesat replica

    Last year, two satellites the size of cereal boxes sped toward Mars as though they were on an invisible track in space. Officially called MarCO A and MarCO B, engineers at NASA had nicknamed them Wall-E and EVE, after the cartoon robots from the Pixar movie.

    They were just as endearing and vulnerable as their namesakes. The satellites, known as cubesats, were sent to watch over NASA’s larger InSight spacecraft as it attempted a perilous landing on the surface of Mars at the end of November.

    NASA/Mars InSight Lander

    Constellations of small satellites like the MarCOs now orbit Earth, used by scientists, private companies, high school students and even governments seeking low-budget eyes in the skies. But never before had a cubesat traveled 90 million miles into space.

    On Nov. 26, as the InSight lander touched down, its status was swiftly relayed back to Earth by the two trailing cubesats. The operation was a success, and the performance of the MarCO satellites may change the way missions operate, enabling cubesats to become deep space travelers in their own right.

    NASA engineers weren’t sure what to expect when the MarCO mission launched last May. “I think it’s opened up so many doors and kind of shattered expectations,” said Anne Marinan, a systems engineer at the Jet Propulsion Laboratory in Pasadena, Calif. “The fact that we actually got as far as we did with both satellites working was huge.”

    About a month after dropping InSight onto Mars, NASA lost contact with the MarCOs. The agency may attempt to wake them up someday, but for now Wall-E and EVE are silently roaming the solar system, proof of a new space exploration technology that almost never got to the launchpad.

    Uncanceling the cubesat program

    The MarCO mission was canceled repeatedly. After all, the primary goal of NASA’s InSight mission was to land a stationary spacecraft on Mars and listen for marsquakes, giving scientists an improved picture of the red planet’s internal makeup.

    And multiple spacecraft orbiting Mars already relay information from its surface back to Earth. The cubesats wouldn’t play a direct role in InSight’s success or failure, so it was a challenge to persuade NASA to support a nonessential program using unproven technology.

    The MarCO team fought hard, prevailing at last with the argument that at a cost of only $18 million, the idea was worth taking a chance on. If these two tiny satellites worked well, it would not only mean that similar spacecraft could support big planetary missions in the future, but also that cubesats might carry instruments of their own.

    Proving the technology’s reach could stretch NASA’s funding, the engineers said, while creating opportunities for wider exploration of the solar system.

    As InSight safely touched down on Mars, the MarCOs were zipping past the planet, collecting readings from the landing and relaying them home more swiftly than the satellites currently orbiting Mars could.

    “We had some astonishing statistics,” said John Baker, manager of the SmallSat program at J.P.L. “We ended up getting 97 percent of all the InSight data back. And that’s because we had two small spacecraft at exactly the right position over the planet to receive the signals.”

    2
    A picture taken by the InSight lander on Mars’s surface in December.Credit NASA, via Associated Press

    3
    Mars, seen by the MarCO B cubesat, about 4,700 miles from the planet in November. Credit Agence France-Presse — Getty Images

    3
    From left, John Baker, Anne Marinan and Andrew Klesh, engineers who led the MarCO mission at J.P.L. Credit Rozette Rago for The New York Times.

    Having custom cubesats overhead meant that NASA did not need to use other Martian satellites or worry about their alignment at the time of landing. If future missions tow along their own MarCOs, teams back on Earth may always know how their spacecraft are doing.

    The creativity of their design contributed to the cubesats’ success. Before they began constructing the MarCOs, the team made 3D models and used yarn to plan how best to run the guts and wiring inside. The MacGyver-like improvisation resulted in part from the program’s low budget.

    The cubesats run on solar power, and their propellant is fire extinguisher fluid. Lining the front of both spacecraft are eight pen-width nozzles that spray cold gas. The cameras onboard are off-the-shelf, and the radio is similar to that in an iPhone.

    But it wasn’t all easy. On their six-month journey to Mars, both cubesats occasionally lost contact with Earth. A couple of months after launch, MarCO B sprang a fuel leak and started spinning out of control. The team thought they’d lost it.

    “Management is slowly encroaching upon the room,” said Andrew Klesh, MarCO’s chief engineer, describing the scene. “We started to look at all the data. We broke apart the problem, and within about 24 hours we had MarCO B back under control.”

    Just a day before landing, MarCO B stopped communicating with Earth again. The cubesat came back online just in time. The InSight probe moved into the Martian landing phase that NASA officials know as “seven minutes of terror,” and both spacecraft spoke to Earth the entire time.

    The future is getting smaller

    NASA JPL Misson Control. Rozette Rago for The New York Times

    While inexpensive cubesats like the MarCOs may serve as real-time communication relays for future deep-space missions, NASA has more adventurous goals in mind, some of which were hinted at in last week’s budget proposals by the Trump administration.

    “When we have big spacecraft, you don’t want to necessarily take it into a very risky situation,” said Mr. Baker. “But you can take an inexpensive probe and send it down to search or to get up close to something and examine it.”

    Mr. Baker and others at J.P.L. are currently working on planetary cubesat missions. One proposal, nicknamed Cupid’s Arrow, envisions using the spacecraft to study the opaque atmosphere of Venus.

    In other proposals, the next iteration of interplanetary cubesats would be scouts deployed by larger spacecraft studying worlds that could be hospitable to life. They could be sent into the plumes of Enceladus, Saturn’s icy moon, which ejects water vapor into space. Or cubesats could descend toward the surface of Europa, the ocean moon of Jupiter.

    “These spacecraft will allow us to act as the Star Trek probes to go down to the surface of challenging worlds where we might not be able to take the risk of a much larger mission,” said Dr. Klesh.

    When NASA’s next-generation rocket, the Space Launch System, heads for its first practice orbit around the moon (a launch which is facing delays), it will carry 13 cubesats, some as tests of technology and others as science experiments.

    NASA Space Launch System depiction

    One cubesat, for example, will be tasked with mapping sources of water on the moon for future human exploration. Another, called NEA Scout, is being designed by Dr. Marinan to monitor nearby asteroids that could pose potential hazards to our planet.

    Private companies are working on shrinking scientific instruments to be placed aboard the next generation of Earth-orbiting satellites. And as instruments become smaller, the options for singular scientific missions in deep space become greater, as does the potential for whole fleets of MarCO-like satellites.

    Toughening tiny travelers

    But much work remains before more cubesats can travel beyond the moon. The challenges that come with operating full-size planetary missions apply to small satellites, too.

    If you want to go to the Jovian system, you need heavy radiation shielding. If you want to go to Saturn, you need more efficient solar panels and ways to keep the tiny spacecraft warm.

    “We think we can actually send a small spacecraft all the way to Jupiter,” said Dr. Baker. “The problem is, I have to come up with a way of automating the onboard spacecraft so that it can fly itself to Jupiter or you only have to talk to it once a month. Or we create a way for it to only radio home when it needs help.”

    These are the kinds of engineering challenges the MarCO team worked to overcome with the journey to Mars.

    “It’s really opened a door of possibilities now that we have shown that this has actually worked,” said Dr. Marinan. “It’s not an impossible concept anymore”

    The engineers even managed to get around one of the tricker issues with how to collect data and talk to the cubesats. Typically, when a spacecraft calls home, it will spend several hours using NASA’s Deep Space Network, the very expensive phone system for calls beyond the moon.

    NASA Deep Space Network


    NASA Deep Space Network Madrid Spain


    NASA Deep Space Network dish, Goldstone, CA, USA


    NASA Canberra, AU, Deep Space Network

    But these long-distance conversations weren’t an option for the MarCOs. So the team at J.P.L. created new ways of monitoring the spacecraft that allowed them to collect in a one-hour period the data that would usually take eight hours.

    “MarCO is a herald of new things to come,” said Dr. Klesh. “Not necessarily better things, but different, and a new way of space exploration that will complement all the larger missions that we do.”

    As it passed Mars, MarCO B returned the first photo ever taken from a cubesat in deep space. It revealed the copper-colored entirety of Mars in the dark of space, and a small section of the spacecraft’s antenna.

    The angle of the photo was intentional — not only to show where we’ve been, but a hint at where these tiny wanderers could go next.

    See the full article here .

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  • richardmitnick 9:29 am on March 17, 2019 Permalink | Reply
    Tags: "Ebola Epidemic in Congo Could Last Another Year C.D.C. Director Warns", , , NYT   

    From The New York Times: “Ebola Epidemic in Congo Could Last Another Year, C.D.C. Director Warns” 

    New York Times

    From The New York Times

    March 16, 2019
    Denise Grady

    1
    A health care worker washing protective gear in Beni, Democratic Republic of Congo, in December. Credit Goran Tomasevic/Reuters

    The Ebola outbreak in the Democratic Republic of Congo is not under control and could continue for another year, Dr. Robert R. Redfield, director of the Centers for Disease Control and Prevention, said in an interview on Friday.

    “Let’s not underestimate this outbreak,” he said.

    His outlook was less optimistic than that of the director general of the World Health Organization, Dr. Tedros Adhanom Ghebreyesus, who said at a news conference on Thursday that his goal was to end the outbreak in six months.

    Dr. Redfield has just returned from a trip to the region that included a visit on March 9 to a treatment center in Butembo that, just hours before, had come under gunfire by attackers who killed a police officer. It was the second attack on that center.

    Another was attacked on Thursday.

    Also on Thursday, Dr. Redfield related his observations from the region, telling a Senate subcommittee that sometime between May and mid-September, Congo could run out of an Ebola vaccine that is widely believed to have kept the epidemic from becoming even worse.

    More than 87,000 people have received the vaccine, which is being donated by its manufacturer, Merck. The vaccine is not yet licensed and cannot be sold. So far, Merck has donated 133,000 doses.

    In response to Dr. Redfield’s warning that vaccine supplies could become dangerously low, Pamela L. Eisele, a spokeswoman for Merck, said in an email that the company could not comment on the C.D.C.’s projections. She also said that Merck keeps a stockpile of 300,000 doses, which it replenishes by making more vaccine whenever doses are deployed for outbreaks.

    “Our commitment is to keep at least 300,000 doses,” she said.

    This outbreak began in August. There had been 932 cases and 587 deaths as of Wednesday, according to the World Health Organization. The epidemic is the second largest ever, after the one in West Africa from 2014 to 2016, which killed more than 11,000 people.

    The disease has struck two of Congo’s northeastern provinces, North Kivu and Ituri, a conflict zone where people have for decades lived in fear of armed militias, the police and soldiers. The most heavily affected areas are urban, with a surrounding population of about one million.

    The region is close to Rwanda, South Sudan and Uganda, and tens of thousands of people cross those borders every day. Some 20 million have gone back and forth from the outbreak zone since August, Dr. Redfield estimated, and added, “Truly, it’s nearly miraculous that we haven’t seen cross-border spread yet.”

    The C.D.C. has worked with the neighboring countries to set up screening stations to stop the disease from reaching them. Some travelers with suspicious symptoms have been tested, but so far none have been infected.

    Dr. Redfield said that experts from his agency could do more to help stop the disease, but that so far, because of violence in the area, the United States government had not permitted them to work where they are needed most, in the epicenters of the outbreak. Some were deployed in August to Beni, but were quickly relocated because of unrest in the area. C.D.C. employees are working in other parts of Congo, however, to train health workers and help coordinate the response.

    The State Department decides whether it is safe for government employees to work in other countries.

    “We’re ready to deploy as soon as they tell us it’s time,” Dr. Redfield said.

    He noted that health workers from the World Health Organization, Doctors Without Borders, Alima and other aid groups, had been working nonstop in the region for more than seven months. Fatigue was setting in, he said, and workers needed reinforcements, especially leaders with deep experience in this kind of outbreak.

    Several red flags indicate that the outbreak is not under control, Dr. Redfield said. One is that too many people — about 40 percent — are dying at home and never going to treatment centers. There is a high risk that they have infected family members, health workers and other patients at local clinics they might have gone to for help. The disease is spread by bodily fluids and becomes highly contagious when symptoms start.

    Corpses are very infectious and pose a big risk to relatives who may wash, dress and prepare them for burial.

    To control an outbreak, at least 70 percent of patients need to be isolated and treated safely in isolation units so that they do not infect anyone else, and that percentage needs to be maintained for several months. In the epicenters in Congo now, that figure is only about 58 percent, Dr. Redfield said.

    Another bad sign is that too many new cases are turning up who were not known contacts of patients and were not being monitored, meaning they could have infected yet more unknown people.

    Also problematic is that a high percentage of patients, about 25 percent, became infected at local health centers, and about 75 health workers from those centers have also been infected. Rates that high indicate that information about the disease and how to avoid spreading it have not reached those clinics.

    Many patients in the current outbreak, about 30 percent, have been children, and doctors say they think some caught Ebola when they were taken to local clinics for other illnesses.

    In addition, the contact tracing has not always been effective. In some cases, if contacts missed a scheduled appointment to be checked for symptoms, their names were simply dropped from the list, Dr. Redfield said.

    He said one incentive to encourage contacts to cooperate was to offer food if they showed up. But then a decision was made locally to hand out the food at a central location, which defeated the purpose of using it as an incentive.

    He said local workers needed on-the-ground training in person from experts in this kind of epidemiologic work — something the C.D.C. can offer if its employees are given permission to deploy into the hot zones.

    Dr. Redfield also echoed a concern expressed by Dr. Joanne Liu, the president of Doctors Without Borders, that medical teams had not fully gained the trust of the affected communities. Without that connection, people will continue to avoid testing and treatment, and decline help in carrying out safe funerals and burials.

    “How exactly to accomplish that is going to take some time, some thought,” Dr. Redfield said. “I haven’t seen evidence to date that we have an effective partnership with the community.”

    Speaking to the Senate subcommittee, he said: “The community doesn’t trust its own government. And it sure doesn’t trust outsiders.”

    2
    Health workers with a coffin of a child suspected of dying from Ebola in Beni, Democratic Republic of Congo, in December. Credit Goran Tomasevic/Reuters

    See the full article here .

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  • richardmitnick 10:52 am on March 9, 2019 Permalink | Reply
    Tags: "Bit by Bit Scientists Gain Ground on AIDS", A a relatively new drug dolutegravir was better than the standard treatment for women about to give birth, A study of the “test and treat” strategy in one million people in South Africa and Zambia — the largest H.I.V. prevention study ever conducted — produced mixed results., Both studies tested monthly injections of cabotegravir and rilpivirine deep into the buttocks., But offering immediate treatment to all did not help as much as had been expected., But other research released this week showed that scientists are making slow but steady progress on the tactics and medicines needed to fight the epidemic especially in Africa, But other studies have suggested that Descovy is more likely to raise cholesterol., Doctors working in poor countries are eager for injections or implants that will release small daily doses of antiretroviral drugs because the devices can be used in secrecy., In another study Descovy a new formulation of the H.I.V. treatment Truvada proved just as effective at suppressing the virus, In poor countries cabotegravir may be especially useful because it does not need to be refrigerated., It was assumed that communities where patients were offered treatment immediately would have by far the lowest rates of new infection. But they did not., Long-lasting contraceptive injections like Depo-Provera are much more popular in Africa than in the United States because many women must conceal birth control from their partners, Many gay or bisexual men would welcome a discreet way to take H.I.V. drugs, Monthly injections of long-acting H.I.V. drugs proved as good as daily pills at suppressing the virus, NYT, Offering treatment without offering PrEP at the same time “is not the way to epidemic control. Frustrating!, Offering widespread home testing plus treatment to the sickest patients did reduce the number of new infections., Only 43 percent of the women who got older efavirenz-based combinations reached that benchmark., People who take Truvada every day as PrEP or pre-exposure prophylaxis are almost 100 percent protected against getting H.I.V. whether from unprotected sex or drug injection., Post-trial surveys found that 98 percent of the subjects preferred injections to pills., Providing injections may be harder than handing out pills but the option may attract patients with H.I.V. who would otherwise stay away., Proving that injectable H.I.V. drugs work is important because many people forget to take their daily pills or cannot keep pills in their homes., The clinical trial involving Descovy showed that it suppressed the virus just as well as Truvada did., The pregnancy trial called Dolphin-2 showed that 74 percent of women who got dolutegravir-based drug cocktails in their third trimester had no H.I.V. in their blood when they gave birth., The shots worked and only a handful of participants dropped out complaining they were too painful., The success of the two injectable-drug studies named Atlas and Flair raised hopes among H.I.V. experts that these shots may eventually be used to protect the uninfected., The trial known as Discover found that Descovy was slightly less likely than Truvada to harm kidneys or bone density., The unnamed “London patient” — the second person apparently cured of H.I.V. — earned all the headlines, Truvada has been very safe for most patients but its high price now about $20000 a year and the red tape needed to help the uninsured pay for it have become major obstacles to ending the AIDS epidemic   

    From The New York Times: “Bit by Bit, Scientists Gain Ground on AIDS” 

    New York Times

    From The New York Times

    March 8, 2019
    Donald G. McNeil Jr.

    1
    Students from the University of the Witwatersrand in Johannesburg explained how to use a self-testing H.I.V. kit last year. Credit Mujahid Safodien/Agence France-Presse — Getty Images

    The unnamed “London patient” — the second person apparently cured of H.I.V. — earned all the headlines. But other research released this week at the Conference on Retroviruses and Opportunistic Infections showed that scientists are making slow but steady progress on the tactics and medicines needed to fight the epidemic, especially in Africa.

    Monthly injections of long-acting H.I.V. drugs proved as good as daily pills at suppressing the virus, according to two trials involving more than 1,000 patients. In another study, Descovy, a new formulation of the H.I.V. treatment Truvada, proved just as effective at suppressing the virus, and may have fewer — or at least different — side effects.

    A study of the “test and treat” strategy in one million people in South Africa and Zambia — the largest H.I.V. prevention study ever conducted — produced mixed results.

    Offering widespread home testing plus treatment to the sickest patients did reduce the number of new infections. But offering immediate treatment to all did not help as much as had been expected.

    And a study of pregnant women in Uganda and South Africa showed that a relatively new drug, dolutegravir, was better than the standard treatment for women about to give birth.

    The results of those trials were revealed at the C.R.O.I. meeting in Seattle, a scientific conference held each year in the United States. It tends to offer more research and fewer theatrics than the International AIDS Society conferences that move to new cities around the globe every two years.

    Proving that injectable H.I.V. drugs work is important because many people forget to take their daily pills or cannot keep pills in their homes.

    The success of the two injectable-drug studies named Atlas and Flair [nam] raised hopes among H.I.V. experts that these shots may eventually be used to protect the uninfected. (Trials testing that idea are underway now, but results are not expected for about three years.)

    Doctors working in poor countries are eager for injections or implants that will release small daily doses of antiretroviral drugs because the devices can be used in secrecy. Providing injections may be harder than handing out pills, but the option may attract patients with H.I.V. who would otherwise stay away.

    3
    A study of pregnant women in Uganda and South Africa found dolutegravir to be more effective in fighting H.I.V. than the standard treatment. Credit Baz Ratner/Reuters

    African women often say they cannot be caught with pills, microbicides, vaginal rings or other anti-H.I.V. measures because they fear that their husbands, lovers, family members or neighbors will mistakenly assume they are infected.

    Long-lasting contraceptive injections like Depo-Provera are much more popular in Africa than in the United States because many women must conceal birth control from their partners, who may get angry that they do not want more children.

    Similarly, many gay or bisexual men would welcome a discreet way to take H.I.V. drugs because they are hiding from their spouses or families that they have sex with men.

    Both studies tested monthly injections of cabotegravir and rilpivirine deep into the buttocks. The shots worked, and only a handful of participants dropped out complaining they were too painful. Post-trial surveys found that 98 percent of the subjects preferred injections to pills.

    In poor countries, cabotegravir may be especially useful because it does not need to be refrigerated.

    The clinical trial involving Descovy, a new pill from Gilead Sciences containing a form of tenofovir known as TAF — instead of TDF, the form in Truvada — showed that it suppressed the virus just as well as Truvada did.

    People who take Truvada every day as PrEP, or pre-exposure prophylaxis, are almost 100 percent protected against getting H.I.V., whether from unprotected sex or drug injection.

    The trial, known as Discover, found that Descovy was slightly less likely than Truvada to harm kidneys or bone density, but other studies have suggested that Descovy is more likely to raise cholesterol.

    Gilead said it will soon ask the Food and Drug Administration to let it market Descovy as PrEP. Some AIDS activists worry that people at risk will be urged to switch to Descovy just as low-cost generic versions of Truvada become available.

    Truvada has been very safe for most patients, but its high price — now about $20,000 a year — and the red tape needed to help the uninsured pay for it have become major obstacles to ending the AIDS epidemic in the United States.

    Gilead has already sold $33 billion worth of tenofovir; it is now shifting its new H.I.V. drug cocktails to TAF, which will remain patented — and, presumably, expensive — for many more years.

    The trial in 21 neighborhoods in Zambia and South Africa — a region where H.I.V. infection rates are the world’s highest — was designed to see whether infection rates could be dramatically [nam] cut if teams of counselors went door-to-door, testing anyone who agreed and offering pills to anyone testing positive. Counselors also offered advice, condoms, circumcisions, tuberculosis tests and other incentives to lower infection rates during the trial, which is known as PopArt and ran from 2013 to 2018.

    It was assumed that communities where patients were offered treatment immediately would have by far the lowest rates of new infection. But they did not, even though tests suggested that more people there were taking their pills; further analysis of that quandary will be done, the investigators said.

    “PopArt is a head-scratcher,” Mitchell J. Warren, executive director of A.V.A.C., an advocacy group for H.I.V. prevention, said in an email.

    Combining the results of the two main subgroups — those offered pills immediately and those offered pills only when they showed early signs of illness — showed that these strategies lowered new infections by about 20 percent.

    Therefore, Mr. Warren said, offering treatment without offering PrEP at the same time “is not the way to epidemic control. Frustrating!”

    The pregnancy trial, called Dolphin-2, showed that 74 percent of women who got dolutegravir-based drug cocktails in their third trimester had no H.I.V. in their blood when they gave birth. Only 43 percent of the women who got older efavirenz-based combinations reached that benchmark.

    That was a “highly significant” difference in how fast each drug drove the virus out of the blood, said Dr. Saye Khoo, an H.I.V. specialist at the University of Liverpool who led the trial.

    That is important because many women in Africa find out they are infected late in pregnancy, and it can be hard to prevent them from infecting their babies.

    Some babies in each test group died, and a few were born infected anyway. The investigators believed the deaths were from unrelated causes like sepsis or pneumonia, and that the rare H.I.V. infections occurred early in the pregnancies, before either drug regimen could kick in.

    See the full article here .

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  • richardmitnick 1:41 pm on March 6, 2019 Permalink | Reply
    Tags: "Another Obstacle for Women in Science: Men Get More Federal Grant Money", Among the top 50 institutions funded by the N.I.H. the researchers found that women received median awards of $94000 compared with $135000 for men, At the Big Ten schools including Penn State the University of Michigan and Northwestern female principal investigators received a median grant of $66000 compared with $148000 for men, “It means women are working harder with less money to get to the same level as men” said Dr. Woodruff a researcher at the Northwestern University Feinberg School of Medicine, “That first grant is monumentally important and determines your trajectory” said Carolina Abdala a head and neck specialist at the University of Southern California who won her first N.I.H. grant , But when it comes to the size of those awards men are often rewarded with bigger grants than women according to a study published Tuesday in JAMA, For ambitious young scientists trying to start their own research labs winning a prestigious grant from the National Institutes of Health can be career making, Having less money put women at a disadvantage making it harder to hire graduate students and buy lab equipment, Identifying the problem is a step toward solving the problem, NYT, Only one in five applicants for an N.I.H. grant lands one, Over all the median N.I.H. award for female researchers at universities was roughly $126600 compared with $167700 for men., The disparity was even greater at the nation’s top universities, The N.I.H. did not dispute the study’s findings and said it was working to address the funding disparities and more broadly the gender inequities that bedevil women in the fields, The study analyzed 54000 grants awarded from 2006 to 2017 and used key benchmarks to ensure recipients were at similar points in their careers, The study by researchers at Northwestern University confirms longstanding disparities between men and women in the fields of science, There was one exception to the pattern- the study found that women who were applying for individual research grants received nearly $16000 more than male applicants 11% of grants,   

    From The New York Times: Women in STEM-“Another Obstacle for Women in Science: Men Get More Federal Grant Money” 

    New York Times

    From The New York Times

    March 5, 2019
    Andrew Jacobs

    1
    A scientist working with radioactive material in the isotope laboratory of the National Institutes of Health, circa 1950. Credit National Institutes of Health.

    For ambitious young scientists trying to start their own research labs, winning a prestigious grant from the National Institutes of Health can be career making.

    But when it comes to the size of those awards, men are often rewarded with bigger grants than women, according to a study published Tuesday in JAMA, which found that men who were the principal investigators on research projects received $41,000 more than women.

    The disparity was even greater at the nation’s top universities. At Yale, women received $68,800 less than men, and at Brown, the median disparity was $76,500. Over all, the median N.I.H. award for female researchers was roughly $126,600, compared with $167,700 for men.

    The study, by researchers at Northwestern University, confirms longstanding disparities between men and women in the field of science. In recent years, a cavalcade of studies has documented biases that favor male researchers in hiring, pay, prize money, speaking invitations and even the effusiveness displayed in letters of recommendation.

    “It’s disappointing, but identifying the problem is a step toward solving the problem,” said Cori Bargmann, a neuroscientist who runs the $3 billion science arm of the Chan Zuckerberg Initiative, a philanthropic organization, and who was not involved in the study.

    In a statement, the N.I.H. did not dispute the study’s findings and said it was working to address the funding disparities and, more broadly, the gender inequities that bedevil women in the field.

    “We have and continue to support efforts to understand the barriers and factors faced by women scientists and to implement interventions to overcome them,” it said.

    Only one in five applicants for an N.I.H. grant lands one, an achievement that can be crucial in whether a young researcher succeeds or drops out of the field.

    “That first grant is monumentally important and determines your trajectory,” said Carolina Abdala, a head and neck specialist at the University of Southern California, who won her first N.I.H. grant in 1998. “It can help get you on the tenure track and it gets you into that club of successful scientists who can procure their own funding, which makes it easier to change jobs.”

    But the size of the grant can also be important in determining the scale and ambition of a junior researcher’s first lab. Teresa K. Woodruff, a co-author of the JAMA study, said that having less money put women at a disadvantage, making it harder to hire graduate students and buy lab equipment.

    “It means women are working harder with less money to get to the same level as men,” said Dr. Woodruff, a researcher at the Northwestern University Feinberg School of Medicine. “If we had the same footing, the engine of science would move a little faster toward the promise of basic science and medical cures.”

    The study analyzed 54,000 grants awarded from 2006 to 2017 and used key benchmarks to ensure recipients were at similar points in their careers. Among the top 50 institutions funded by the N.I.H., the researchers found that women received median awards of $94,000 compared with $135,000 for men. At the Big Ten schools, including Penn State, the University of Michigan and Northwestern, female principal investigators received a median grant of $66,000 compared with $148,000 for men.

    There was one exception to the pattern; in a curious twist, the study found that women who were applying for individual research grants received nearly $16,000 more than male applicants. Dr. Woodruff noted that such grants made up only 11 percent of N.I.H. grant money, but said more research was needed into funding disparities.

    See the full article here .

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  • richardmitnick 7:01 pm on February 25, 2019 Permalink | Reply
    Tags: A disturbance in the Force, Adam Riess [High-Z Supernova Search Team] Saul Perlmutter [Supernova Cosmology Project] and Brian Schmidt [High-Z Supernova Search Team]shared the Nobel Prize in physics awarded in 2011 for proving th, As space expands it carries galaxies away from each other like the raisins in a rising cake. The farther apart two galaxies are the faster they will fly away from each other. The Hubble constant simpl, , , Axions? Phantom energy? Astrophysicists scramble to patch a hole in the universe- rewriting cosmic history in the process, , , , Dark energy might be getting stronger and denser leading to a future in which atoms are ripped apart and time ends, , NYT, The Hubble constant- named after Edwin Hubble the Mount Wilson astronomer who in 1929 discovered that the universe is expanding, Thus far there is no evidence for most of these ideas, Under the influence of dark energy the cosmos is now doubling in size every 10 billion years   

    From The New York Times: “Have Dark Forces Been Messing With the Cosmos?” 

    New York Times

    From The New York Times

    Feb. 25, 2019
    Dennis Overbye

    1
    Brian Stauffer

    Axions? Phantom energy? Astrophysicists scramble to patch a hole in the universe, rewriting cosmic history in the process.

    There was, you might say, a disturbance in the Force.

    Long, long ago, when the universe was only about 100,000 years old — a buzzing, expanding mass of particles and radiation — a strange new energy field switched on. That energy suffused space with a kind of cosmic antigravity, delivering a not-so-gentle boost to the expansion of the universe.

    Then, after another 100,000 years or so, the new field simply winked off, leaving no trace other than a speeded-up universe.

    So goes the strange-sounding story being promulgated by a handful of astronomers from Johns Hopkins University. In a bold and speculative leap into the past, the team has posited the existence of this field to explain an astronomical puzzle: the universe seems to be expanding faster than it should be.

    The cosmos is expanding only about 9 percent more quickly than theory prescribes. But this slight-sounding discrepancy has intrigued astronomers, who think it might be revealing something new about the universe.

    And so, for the last couple of years, they have been gathering in workshops and conferences to search for a mistake or loophole in their previous measurements and calculations, so far to no avail.

    “If we’re going to be serious about cosmology, this is the kind of thing we have to be able to take seriously,” said Lisa Randall, a Harvard theorist who has been pondering the problem.

    At a recent meeting in Chicago, Josh Frieman, a theorist at the Fermi National Accelerator Laboratory in Batavia, Ill., asked: “At what point do we claim the discovery of new physics?”

    Now ideas are popping up. Some researchers say the problem could be solved by inferring the existence of previously unknown subatomic particles. Others, such as the Johns Hopkins group, are invoking new kinds of energy fields.

    Adding to the confusion, there already is a force field — called dark energy — making the universe expand faster. And a new, controversial report suggests that this dark energy might be getting stronger and denser, leading to a future in which atoms are ripped apart and time ends.

    Dark Energy Survey


    Dark Energy Camera [DECam], built at FNAL


    NOAO/CTIO Victor M Blanco 4m Telescope which houses the DECam at Cerro Tololo, Chile, housing DECam at an altitude of 7200 feet

    Thus far, there is no evidence for most of these ideas. If any turn out to be right, scientists may have to rewrite the story of the origin, history and, perhaps, fate of the universe.

    Or it could all be a mistake. Astronomers have rigorous methods to estimate the effects of statistical noise and other random errors on their results; not so for the unexamined biases called systematic errors.

    As Wendy L. Freedman, of the University of Chicago, said at the Chicago meeting, “The unknown systematic is what gets you in the end.”

    2
    Edwin Hubble in 1949, two decades after he discovered that the universe is expanding.CreditBoyer/Roger Viollet, via Getty Images

    Hubble trouble

    Generations of great astronomers have come to grief trying to measure the universe. At issue is a number called the Hubble constant, named after Edwin Hubble, the Mount Wilson astronomer who in 1929 discovered that the universe is expanding.

    Edwin Hubble looking through a 100-inch Hooker telescope at Mount Wilson in Southern California

    Mt Wilson 100 inch Hooker Telescope, perched atop the San Gabriel Mountains outside Los Angeles, CA, USA, Mount Wilson, California, US, Altitude 1,742 m (5,715 ft)

    As space expands, it carries galaxies away from each other like the raisins in a rising cake. The farther apart two galaxies are, the faster they will fly away from each other. The Hubble constant simply says by how much.

    But to calibrate the Hubble constant, astronomers depend on so-called standard candles: objects, such as supernova explosions and certain variable stars, whose distances can be estimated by luminosity or some other feature. This is where the arguing begins.

    Standard Candles to measure age and distance of the universe NASA

    Until a few decades ago, astronomers could not agree on the value of the Hubble constant within a factor of two: either 50 or 100 kilometers per second per megaparsec. (A megaparsec is 3.26 million light years.)

    But in 2001, a team using the Hubble Space Telescope, and led by Dr. Freedman, reported a value of 72. For every megaparsec farther away from us that a galaxy is, it is moving 72 kilometers per second faster.

    NASA/ESA Hubble Telescope

    More recent efforts by Adam G. Riess, of Johns Hopkins and the Space Telescope Science Institute, and others have obtained similar numbers, and astronomers now say they have narrowed the uncertainty in the Hubble constant to just 2.4 percent.

    But new precision has brought new trouble. These results are so good that they now disagree with results from the European Planck spacecraft, which predict a Hubble constant of 67.

    ESA/Planck 2009 to 2013

    4
    Workers with the European Planck spacecraft at the European Space Agency spaceport in Kourou, French Guiana, in 2009.CreditESA – S. Corvaja

    The discrepancy — 9 percent — sounds fatal but may not be, astronomers contend, because Planck and human astronomers do very different kinds of observations.

    Planck is considered the gold standard of cosmology. It spent four years studying the cosmic bath of microwaves [CMB] left over from the end of the Big Bang, when the universe was just 380,000 years old.

    CMB per ESA/Planck

    But it did not measure the Hubble constant directly. Rather, the Planck group derived the value of the constant, and other cosmic parameters, from a mathematical model largely based on those microwaves.

    In short, Planck’s Hubble constant is based on a cosmic baby picture. In contrast, the classical astronomical value is derived from what cosmologists modestly call “local measurements,” a few billion light-years deep into a middle-aged universe.

    What if that baby picture left out or obscured some important feature of the universe?

    ‘Cosmological Whac-a-Mole’

    And so cosmologists are off to the game that Lloyd Knox, an astrophysicist from the University of California, Davis, called “cosmological Whac-a-Mole” at the recent Chicago meeting: attempting to fix the model of the early universe, to make it expand a little faster without breaking what the model already does well.

    One approach, some astrophysicists suggest, is to add more species of lightweight subatomic particles, such as the ghostlike neutrinos, to the early universe. (Physicists already recognize three kinds of neutrinos, and argue whether there is evidence for a fourth variety.) These would give the universe more room to stash energy, in the same way that more drawers in your dresser allow you to own more pairs of socks. Thus invigorated, the universe would expand faster, according to the Big Bang math, and hopefully not mess up the microwave baby picture.

    A more drastic approach, from the Johns Hopkins group, invokes fields of exotic anti-gravitational energy. The idea exploits an aspect of string theory, the putative but unproven “theory of everything” that posits that the elementary constituents of reality are very tiny, wriggling strings.

    String theory suggests that space could be laced with exotic energy fields associated with lightweight particles or forces yet undiscovered. Those fields, collectively called quintessence, could act in opposition to gravity, and could change over time — popping up, decaying or altering their effect, switching from repulsive to attractive.

    The team focused in particular on the effects of fields associated with hypothetical particles called axions. Had one such field arisen when the universe was about 100,000 years old, it could have produced just the right amount of energy to fix the Hubble discrepancy, the team reported in a paper late last year. They refer to this theoretical force as “early dark energy.”

    “I was surprised how it came out,” said Marc Kamionkowski, a Johns Hopkins cosmologist who was part of the study. “This works.”

    The jury is still out. Dr. Riess said that the idea seems to work, which is not to say that he agrees with it, or that it is right. Nature, manifest in future observations, will have the final say.

    Dr. Knox called the Johns Hopkins paper “an existence proof” that the Hubble problem could be solved. “I think that’s new,” he said.

    Dr. Randall, however, has taken issue with aspects of the Johns Hopkins calculations. She and a trio of Harvard postdocs are working on a similar idea that she says works as well and is mathematically consistent. “It’s novel and very cool,” Dr. Randall said.

    So far, the smart money is still on cosmic confusion. Michael Turner, a veteran cosmologist at the University of Chicago and the organizer of a recent airing of the Hubble tensions, said, “Indeed, all of this is going over all of our heads. We are confused and hoping that the confusion will lead to something good!”

    Doomsday? Nah, nevermind

    Early dark energy appeals to some cosmologists because it hints at a link to, or between, two mysterious episodes in the history of the universe. As Dr. Riess said, “This is not the first time the universe has been expanding too fast.”

    The first episode occurred when the universe was less than a trillionth of a trillionth of a second old. At that moment, cosmologists surmise, a violent ballooning propelled the Big Bang; in a fraction of a trillionth of a second, this event — named “inflation” by the cosmologist Alan Guth, of M.I.T. — smoothed and flattened the initial chaos into the more orderly universe observed today. Nobody knows what drove inflation.

    The second episode is unfolding today: cosmic expansion is speeding up. But why? The issue came to light in 1998, when two competing teams of astronomers asked whether the collective gravity of the galaxies might be slowing the expansion enough to one day drag everything together into a Big Crunch.

    To great surprise, they discovered the opposite: the expansion was accelerating under the influence of an anti-gravitational force later called dark energy. The two teams won a Nobel Prize.

    Studies of Universe’s Expansion Win Physics Nobel

    By DENNIS OVERBYE OCT. 4, 2011

    3
    From left, Adam Riess [High-Z Supernova Search Team], Saul Perlmutter [Supernova Cosmology Project] and Brian Schmidt [High-Z Supernova Search Team]shared the Nobel Prize in physics awarded Tuesday. Credit Johns Hopkins University; University Of California At Berkeley; Australian National University

    Dark energy comprises 70 percent of the mass-energy of the universe. And, spookily, it behaves very much like a fudge factor known as the cosmological constant, a cosmic repulsive force that Einstein inserted in his equations a century ago thinking it would keep the universe from collapsing under its own weight. He later abandoned the idea, perhaps too soon.

    Under the influence of dark energy, the cosmos is now doubling in size every 10 billion years — to what end, nobody knows.

    Early dark energy, the force invoked by the Johns Hopkins group, might represent a third episode of antigravity taking over the universe and speeding it up. Perhaps all three episodes are different manifestations of the same underlying tendency of the universe to go rogue and speed up occasionally. In an email, Dr. Riess said, “Maybe the universe does this from time-to-time?”

    If so, it would mean that the current manifestation of dark energy is not Einstein’s constant after all. It might wink off one day. That would relieve astronomers, and everybody else, of an existential nightmare regarding the future of the universe. If dark energy remains constant, everything outside our galaxy eventually will be moving away from us faster than the speed of light, and will no longer be visible. The universe will become lifeless and utterly dark.

    But if dark energy is temporary — if one day it switches off — cosmologists and metaphysicians can all go back to contemplating a sensible tomorrow.

    “An appealing feature of this is that there might be a future for humanity,” said Scott Dodelson, a theorist at Carnegie Mellon who has explored similar scenarios [Physical Review D].

    The phantom cosmos

    But the future is still up for grabs.

    Far from switching off, the dark energy currently in the universe actually has increased over cosmic time, according to a recent report in Nature Astronomy. If this keeps up, the universe could end one day in what astronomers call the Big Rip, with atoms and elementary particles torn asunder — perhaps the ultimate cosmic catastrophe.

    This dire scenario emerges from the work of Guido Risaliti, of the University of Florence in Italy, and Elisabeta Lusso, of Durham University in England. For the last four years, they have plumbed the deep history of the universe, using violent, faraway cataclysms called quasars as distance markers.

    Quasars arise from supermassive black holes at the centers of galaxies; they are the brightest objects in nature, and can be seen clear across the universe. As standard candles, quasars aren’t ideal because their masses vary widely. Nevertheless, the researchers identified some regularities in the emissions from quasars, allowing the history of the cosmos to be traced back nearly 12 billion years. The team found that the rate of cosmic expansion deviated from expectations over that time span.

    One interpretation of the results is that dark energy is not constant after all, but is changing, growing denser and thus stronger over cosmic time. It so happens that this increase in dark energy also would be just enough to resolve the discrepancy in measurements of the Hubble constant.

    The bad news is that, if this model is right, dark energy may be in a particularly virulent and — most physicists say — implausible form called phantom energy. Its existence would imply that things can lose energy by speeding up, for instance. Robert Caldwell, a Dartmouth physicist, has referred to it as “bad news stuff.”

    As the universe expands, the push from phantom energy would grow without bounds, eventually overcoming gravity and tearing apart first Earth, then atoms.

    The Hubble-constant community responded to the new report with caution. “If it holds up, this is a very interesting result,” said Dr. Freedman.

    Astronomers have been trying to take the measure of this dark energy for two decades. Two space missions — the European Space Agency’s Euclid and NASA’s Wfirst — have been designed to study dark energy and hopefully deliver definitive answers in the coming decade. The fate of the universe is at stake.

    ESA/Euclid spacecraft

    NASA/WFIRST

    In the meantime, everything, including phantom energy, is up for consideration, according to Dr. Riess.

    “In a list of possible solutions to the tension via new physics, mentioning weird dark energy like this would seem appropriate,” he wrote in an email. “Heck, at least their dark energy goes in the right direction to solve the tension. It could have gone the other way and made it worse!”

    See the full article here .

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