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  • richardmitnick 9:33 am on October 9, 2017 Permalink | Reply
    Tags: , , Baryons, , , , , New Scientist,   

    From New Scientist: “Half the universe’s missing matter has just been finally found” 

    NewScientist

    New Scientist

    9 October 2017
    Leah Crane

    1
    Discoveries seem to back up many of our ideas about how the universe got its large-scale structure
    Andrey Kravtsov (The University of Chicago) and Anatoly Klypin (New Mexico State University). Visualisation by Andrey Kravtsov

    The missing links between galaxies have finally been found. This is the first detection of the roughly half of the normal matter in our universe – protons, neutrons and electrons – unaccounted for by previous observations of stars, galaxies and other bright objects in space.

    Two separate teams found the missing matter – made of particles called baryons rather than dark matter – linking galaxies together through filaments of hot, diffuse gas.

    “The missing baryon problem is solved,” says Hideki Tanimura at the Institute of Space Astrophysics in Orsay, France, leader of one of the groups. The other team was led by Anna de Graaff at the University of Edinburgh, UK.

    Because the gas is so tenuous and not quite hot enough for X-ray telescopes to pick up, nobody had been able to see it before.

    “There’s no sweet spot – no sweet instrument that we’ve invented yet that can directly observe this gas,” says Richard Ellis at University College London. “It’s been purely speculation until now.”

    So the two groups had to find another way to definitively show that these threads of gas are really there.

    Both teams took advantage of a phenomenon called the Sunyaev-Zel’dovich effect that occurs when light left over from the big bang passes through hot gas. As the light travels, some of it scatters off the electrons in the gas, leaving a dim patch in the cosmic microwave background [CMB] – our snapshot of the remnants from the birth of the cosmos.

    CMB per ESA/Planck

    ESA/Planck

    Stack ‘em up

    In 2015, the Planck satellite created a map of this effect throughout the observable universe. Because the tendrils of gas between galaxies are so diffuse, the dim blotches they cause are far too slight to be seen directly on Planck’s map.

    Universe map Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift Survey

    Both teams selected pairs of galaxies from the Sloan Digital Sky Survey that were expected to be connected by a strand of baryons. They stacked the Planck signals for the areas between the galaxies, making the individually faint strands detectable en masse.

    Tanimura’s team stacked data on 260,000 pairs of galaxies, and de Graaff’s group used over a million pairs. Both teams found definitive evidence of gas filaments between the galaxies. Tanimura’s group found they were almost three times denser than the mean for normal matter in the universe, and de Graaf’s group found they were six times denser – confirmation that the gas in these areas is dense enough to form filaments.

    “We expect some differences because we are looking at filaments at different distances,” says Tanimura. “If this factor is included, our findings are very consistent with the other group.”

    Finally finding the extra baryons that have been predicted by decades of simulations validates some of our assumptions about the universe.

    “Everybody sort of knows that it has to be there, but this is the first time that somebody – two different groups, no less – has come up with a definitive detection,” says Ralph Kraft at the Harvard-Smithsonian Center for Astrophysics in Massachusetts.

    “This goes a long way toward showing that many of our ideas of how galaxies form and how structures form over the history of the universe are pretty much correct,” he says.

    Journal references: arXiv, 1709.05024
    A Search for Warm/Hot Gas Filaments Between Pairs of SDSS Luminous Red Galaxies

    and 1709.10378v1
    Missing baryons in the cosmic web revealed by the Sunyaev-Zel’dovich effect

    See the full article here .

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  • richardmitnick 10:28 am on October 8, 2017 Permalink | Reply
    Tags: , By December 1998 the US Food and Drug Administration approved the release of Lymerix developed by SmithKline Beecham now GSK. But the company voluntarily withdrew the drug after only four years, If you do test positive for Lyme disease a course of antibiotics will usually stop the infection in its tracks fairly quickly, If you know it has been on you for under 36 hours use tweezers to pull it out correctly and you will probably be fine, IF YOU’VE MISSED THE WINDOW - It’s best to see a doctor for a Lyme disease test – but not right away. Your antibodies to Lyme disease take weeks to form so an early test can give a false reassur, Left untreated Lyme disease can lead to a host of problems chronic joint inflammation facial palsy issues with short-term memory heart rhythm irregularities and inflammation of the brain and spinal co, Lyme disease is set to explode and we still don’t have a vaccine, Lyme disease is the most common infection following a pest bite in the US, Make sure you check your partner’s armpits scalp and groin for ticks, , Mouse blood carries the Lyme-causing bacterium Borrelia burgdorferi, New Scientist, Nymph ticks are so tiny they can be hard to spot so find a partner strip down and go over places that are hard to reach, Thanks in part to warmer winters the disease is spreading beyond its usual territory extending across the US, The best way to prevent Lyme disease is to do a thorough tick check, This followed a series of lawsuits – including one where recipients claimed Lymerix caused chronic arthritis, We predict the mice population based on the acorns and we predict infected nymph ticks with the mice numbers, When the FDA reviewed the vaccine’s adverse event reports in a retrospective study they found only 905 reports for 1.4 million doses. Still the damage was done and the vaccine was benched   

    From New Scientist: “Lyme disease is set to explode and we still don’t have a vaccine” 

    NewScientist

    New Scientist

    29 March 2017 [Just found this in social media.]
    Chelsea Whyte

    1
    Tick tock. Mike Peres/Custom Medical Stock Photo/SPL

    A new prediction says 2017 and 2018 will see major Lyme disease outbreaks in new areas. This could lead to lifelong health consequences, so where’s the vaccine?

    BY THE time he had finished his walk through the woods in New York state, Rick Ostfeld was ready to declare a public health emergency. He could read the warning signs in the acorns that littered the forest floor – seeds of a chain of events that will culminate in an unprecedented outbreak of Lyme disease this year.

    Since that day in 2015, Ostfeld has been publicising the coming outbreak. Thanks to a changing climate it could be one of the worst on record: the ticks that carry the disease have been found in places where it has never before been a problem – and where most people don’t know how to respond. The danger zone isn’t confined to the US: similar signs are flagging potential outbreaks in Europe. Polish researchers predict a major outbreak there in 2018.

    In theory, Ostfeld’s early warning system gives public health officials a two-year window to prepare. In many other cases, this would be enough time to roll out a vaccination programme. But there is no human vaccine for Lyme disease. Why not? And what can you do to protect yourself in the meantime?

    Lyme disease is the most common infection following a pest bite in the US: the Centers for Disease Control estimates that 300,000 Americans contract Lyme disease each year, calling it “a major US public health problem”. While it is easy enough to treat if caught early, we are still getting to grips with lifelong health problems that can stem from not catching it in time (see “Do I have Lyme disease?“).

    This is less of a problem when Lyme is confined to a few small areas of the US, but thanks in part to warmer winters, the disease is spreading beyond its usual territory, extending across the US (see map) and into Europe and forested areas of Asia. In Europe in particular, confirmed cases have been steadily rising for 30 years – today, the World Health Organization estimates that 65,000 people get Lyme disease each year in the region. In the UK, 2000 to 3000 cases are diagnosed each year, up tenfold from 2001, estimates the UK’s National Health Service.

    So how could a floor of acorns two years ago tell Ostfeld, a disease ecologist at the Cary Institute of Ecosystem Studies in Millbrook, New York, that 2017 would see an outbreak of Lyme disease? It’s all down to what happens next.

    A bumper crop of the seeds – “like you were walking on ball bearings” – comes along every two to five years in Millbrook. Crucially, these nutrient-packed meals swell the mouse population: “2016 was a real mouse plague of a year,” he says. And mouse plagues bring tick plagues.

    Soon after hatching, young ticks start “questing” – grasping onto grasses or leaves with their hind legs and waving their forelegs, ready to hitch a ride on whatever passes by, usually a mouse.

    Gut reaction

    Once on board, the feast begins. Just one mouse can carry hundreds of immature ticks in their post-larval nymph stage.

    This is where the problems for us start. Mouse blood carries the Lyme-causing bacterium Borrelia burgdorferi, which passes to a tick’s gut as it feeds. The tick itself is unharmed, but each time it latches onto a new host to feed, the bacteria can move from its gut to the blood – including that of any human passers-by.

    “We predict the mice population based on the acorns and we predict infected nymph ticks with the mice numbers. Each step has a one year lag,” Ostfeld says.

    Ostfeld published his discovery of this chain of causation in 2006. Last year, researchers in Poland found the same trend there, with the same implications. “Last year we had a lot of oak acorns, so we might expect 2018 will pose a high risk of Lyme,” says Jakub Szymkowiak at Adam Mickiewicz University in Poznan, Poland.

    Those who live in traditional Lyme disease zones are well versed in tick awareness – wear long trousers in the woods, check yourself thoroughly afterwards, and more. But this advice will be less familiar in places that used to sit outside Lyme zones – like Poland. “That’s sort of the perfect storm,” says Ostfeld. “The public is unaware, so they’re not looking for it and they don’t get treated.”

    It’s not obvious when you have been bitten or infected: ticks are the size of a poppy seed, and not everyone gets the classic “bullseye” rash that is supposed to tip you off. The flu-like symptoms that follow are also easy to misdiagnose. And because antibodies to Lyme disease take a few weeks to develop, early tests can miss it. “That’s when you get late-stage, untreated, supremely problematic Lyme disease,” Ostfeld says.

    The best approach would be to vaccinate people at risk – but there is currently no vaccine. We used to have one, but thanks to anti-vaccination activists, that is no longer the case.

    In the late 1990s, a race was on to make the first Lyme disease vaccine. By December 1998, the US Food and Drug Administration approved the release of Lymerix, developed by SmithKline Beecham, now GSK. But the company voluntarily withdrew the drug after only four years.

    2

    This followed a series of lawsuits – including one where recipients claimed Lymerix caused chronic arthritis. Influenced by now-discredited research purporting to show a link between the MMR vaccine and autism, activists raised the question of whether the Lyme disease vaccine could cause arthritis.

    Media coverage and the anti-Lyme-vaccination groups gave a voice to those who believed their pain was due to the vaccine, and public support for the vaccine declined. “The chronic arthritis was not associated with Lyme,” says Stanley Plotkin, an adviser to pharmaceutical company Sanofi Pasteur. “When you’re dealing with adults, all kinds of things happen to them. They get arthritis, they get strokes, heart attacks. So unless you have a control group, you’re in la-la land.”

    But there was a control group – the rest of the US population. And when the FDA reviewed the vaccine’s adverse event reports in a retrospective study, they found only 905 reports for 1.4 million doses. Still, the damage was done, and the vaccine was benched.

    After that, “no one touched it”, says Thomas Lingelbach, CEO at Valneva, a biotech company based in France. Until now: Valneva has a vaccine in early human trials. It will improve on Lymerix, acting against all five strains of the disease instead of just the one most common in the US, and it will be suitable for children.

    Lingelbach knows the battles his firm will face. “It will be hard to convince anti-vax lobbyists,” he says. That fight is still some way off: any public roll-out is at least six years away.

    What makes this wait especially galling for some is that there is a vaccine for your pet. “It’s ironic that you can vaccinate your animal and you can’t vaccinate yourself,” Plotkin says.

    In the animal vaccine, instead of exposing Fido to a weakened version of the antigen to trigger antibodies, it works within the tick, neutralising B. burgdorferi by altering the expression of a protein on the bacterium before it enters the bloodstream. This is how a human version would work. “The underlying scientific principle is not very far away from what it is in the veterinary environment,” says Lingelbach.

    Some people have suggested taking the animal vaccine, but Plotkin doesn’t recommend this as it hasn’t been tested in people so there is insufficient safety data. “You just don’t have classical efficacy data in humans,” he says. It is also illegal in the US and UK for vets to practise medicine on humans.

    While we wait for a human vaccine, you might start keeping track of your local acorn populations – but brush up on your anti-tick measures before you hit the woods.

    _________________________________________________________

    DO I HAVE LYME DISEASE?

    The symptoms of Lyme disease, which you can get from a tick bite, aren’t always obvious. At the site of the bite, a red splotch will often start to grow into what looks like a bullseye target.

    Not everyone gets this unmistakable sign, however. Over the next few weeks, flu-like symptoms, including aches and fever, can follow. Left untreated, Lyme disease can lead to a host of problems, chronic joint inflammation, facial palsy, issues with short-term memory, heart rhythm irregularities, and inflammation of the brain and spinal cord.

    WHAT TO DO

    IF YOU’VE BEEN AROUND TICKS

    The best way to prevent Lyme disease is to do a thorough tick check. Nymph ticks are so tiny they can be hard to spot, so find a partner, strip down, and go over places that are hard to reach. Make sure you check your partner’s armpits, scalp and groin for ticks.

    IF YOU FIND A TICK

    If you know it has been on you for under 36 hours, use tweezers to pull it out correctly, and you will probably be fine. That’s because the Lyme-causing bacteria that live in a tick’s gut are slow, and it takes 36 to 48 hours for them to make it into your bloodstream. Always see a doctor if you are unsure.

    IF YOU’VE MISSED THE WINDOW

    It’s best to see a doctor for a Lyme disease test – but not right away. Your antibodies to Lyme disease take weeks to form, so an early test can give a false reassurance. Wait four to six weeks before requesting a blood test.

    IF YOU TEST POSITIVE

    If you do test positive for Lyme disease, a course of antibiotics will usually stop the infection in its tracks fairly quickly.

    IF SYMPTOMS LINGER

    A small percentage of people who are treated will continue to have symptoms like fatigue or sore joints and muscles. This condition is called post-treatment Lyme disease syndrome, sometimes referred to as chronic Lyme disease. It isn’t exactly clear what causes these symptoms, it could be a delayed immune response or even another illness altogether. Until this controversial area of medicine is clarified, it’s best to avoid getting Lyme disease in the first place, at least while a vaccine is still in development.
    _________________________________________________________

    Article amended on 5 April 2017

    We have corrected how to pull out a tick, and recalled the correct classification of mites.

    See the full article here .

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  • richardmitnick 7:13 am on October 8, 2017 Permalink | Reply
    Tags: , , , , , , New Scientist, , ,   

    From New Scientist: “We still haven’t heard from aliens – here’s why we might never” 

    NewScientist

    New Scientist

    26 April 2017 [Where did this come from? Just found in social media.]
    Leah Crane

    CSIRO/Parkes Observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia

    THE most ambitious search so far for extraterrestrial intelligence has released its first data – and there are no aliens yet. The lack of success could be explained by the result of a new approach to calculating the likelihood of detecting alien signals. This calculation suggests we might never make contact, even if extraterrestrial life is common.

    The search for extraterrestrial intelligence (SETI) has been active for decades.

    Drake Equation, Frank Drake, Seti Institute

    SETI Institute

    SETI/Allen Telescope Array situated at the Hat Creek Radio Observatory, 290 miles (470 km) northeast of San Francisco, California, USA

    SETI@home, BOINC project at UC Berkeley Space Science Lab

    Breakthrough Listen aims to be the largest, most comprehensive search ever. [Using only three telescopes? There are a lot more available.]

    1

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA



    GBO radio telescope, Green Bank, West Virginia, USA


    CSIRO/Parkes Observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia

    The $100 million initiative uses three of the world’s most sensitive telescopes to look for alien signals from the 1 million closest stars to Earth and the 100 closest galaxies.

    “It’s like finding a needle in a haystack,” says Seth Shostak at the SETI Institute in California. “But we don’t know how many needles are there.”

    Breakthrough Listen team members have analysed the light from 692 stars so far. They have found 11 potential alien signals, none of which remained promising after further analysis.

    “It’s the beginning of a very exciting time,” says Avi Loeb at Harvard University. “But while it’s exciting, it’s still very risky. We could find nothing.”

    That’s exactly what an assessment by Claudio Grimaldi at the Swiss Federal Institute of Technology in Lausanne predicts.

    Most methods for calculating the likelihood of detecting alien signals start with an expected number of sources. Instead, Grimaldi started with what volume of the galaxy could be reached by alien signals, a value that requires fewer assumptions about the nature and abundance of extraterrestrial life.

    Grimaldi assumed that signals from an extraterrestrial emitter might get weaker or be blocked as they travel, so they would only cover a certain volume of space. It’s relatively simple to calculate the probability that Earth is within that space and so able to detect the signal. “Not all signals can be visible at the same time – only those that intersect with the Earth,” says Grimaldi.

    He found that even if half of our galaxy was full of alien noise, the average number of signals that we would be able to detect from Earth is less than one (Scientific Reports, doi.org/b562).

    This implies that, even if there are lots of aliens out there, we might never be able to hear from them. But some researchers take umbrage: Grimaldi’s method still requires you to plug in numbers for how far alien signals could be detectable and how long they last – neither of which is known.

    “You have to make some assumptions about what the aliens are doing in all these calculations, unfortunately, and the data set that we have with alien activity is fairly sparse,” says Shostak. Our only example of intelligent life is on Earth, and there’s little reason to expect that ET resembles us.

    But, says Loeb, extraterrestrial signals should be no harder to find than other astronomical events.

    “The question of whether you can detect a signal has nothing to do with whether it’s artificial or natural, and astronomers routinely detect lots of kinds of signals,” he says.

    “In SETI, theory is great, but observation is the gold standard,” says Douglas Vakoch, president of METI International, which aims to send messages to extraterrestrial intelligence.

    METI (Messaging Extraterrestrial Intelligence) International has announced plans to start sending signals into space

    It’s not difficult to think up a different signal that we would be able to detect, he says.

    For example, if there were alien life at the TRAPPIST-1 planets, just 40 light years away, they wouldn’t need particularly advanced technology to contact us.

    A size comparison of the planets of the TRAPPIST-1 system, lined up in order of increasing distance from their host star. The planetary surfaces are portrayed with an artist’s impression of their potential surface features, including water, ice, and atmospheres. NASA

    The TRAPPIST-1 star, an ultracool dwarf, is orbited by seven Earth-size planets (NASA).

    It seems implausible that we would miss their call.

    See the full article here .

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  • richardmitnick 2:21 pm on September 21, 2017 Permalink | Reply
    Tags: But quantum mechanics doesn’t really define what a measurement is, , Gravity at its most fundamental comes in indivisible parcels called quanta, GRW model-Ghirardi–Rimini–Weber theory, In quantum theory the state of a particle is described by its wave function, Much like the electromagnetic force comes in quanta called photons, New Scientist, ,   

    From New Scientist: “Gravity may be created by strange flashes in the quantum realm” 

    NewScientist

    New Scientist

    20 September 2017
    Anil Ananthaswamy

    1
    Gravity comes about in a flash. Emma Johnson/Getty

    HOW do you reconcile the two pillars of modern physics: quantum theory and gravity? One or both will have to give way. A new approach says gravity could emerge from random fluctuations at the quantum level, making quantum mechanics the more fundamental of the two theories.

    Of our two main explanations of reality, quantum theory governs the interactions between the smallest bits of matter. And general relativity deals with gravity and the largest structures in the universe. Ever since Einstein, physicists have been trying to bridge the gap between the two, with little success.

    Part of the problem is knowing which strands of each theory are fundamental to our understanding of reality.

    One approach towards reconciling gravity with quantum mechanics has been to show that gravity at its most fundamental comes in indivisible parcels called quanta, much like the electromagnetic force comes in quanta called photons. But this road to a theory of quantum gravity has so far proved impassable.

    Now Antoine Tilloy at the Max Planck Institute of Quantum Optics in Garching, Germany, has attempted to get at gravity by tweaking standard quantum mechanics.

    In quantum theory, the state of a particle is described by its wave function. The wave function lets you calculate, for example, the probability of finding the particle in one place or another on measurement. Before the measurement, it is unclear whether the particle exists and if so, where. Reality, it seems, is created by the act of measurement, which “collapses” the wave function.

    But quantum mechanics doesn’t really define what a measurement is. For instance, does it need a conscious human? The measurement problem leads to paradoxes like Schrödinger’s cat, in which a cat can be simultaneously dead and alive inside a box, until someone opens the box to look.

    One solution to such paradoxes is a so-called GRW model that was developed in the late 1980s. It incorporates “flashes”, which are spontaneous random collapses of the wave function of quantum systems. The outcome is exactly as if there were measurements being made, but without explicit observers.

    Tilloy has modified this model to show how it can lead to a theory of gravity. In his model, when a flash collapses a wave function and causes a particle to be in one place, it creates a gravitational field at that instant in space-time. A massive quantum system with a large number of particles is subject to numerous flashes, and the result is a fluctuating gravitational field.

    It turns out that the average of these fluctuations is a gravitational field that one expects from Newton’s theory of gravity (arxiv.org/abs/1709.03809). This approach to unifying gravity with quantum mechanics is called semiclassical: gravity arises from quantum processes but remains a classical force. “There is no real reason to ignore this semiclassical approach, to having gravity being classical at the fundamental level,” says Tilloy.

    “I like this idea in principle,” says Klaus Hornberger at the University of Duisburg-Essen in Germany. But he points out that other problems need to be tackled before this approach can be a serious contender for unifying all the fundamental forces underpinning the laws of physics on scales large and small. For example, Tilloy’s model can be used to get gravity as described by Newton’s theory, but the maths still has to be worked out to see if it is effective in describing gravity as governed by Einstein’s general relativity.

    Tilloy agrees. “This is very hard to generalise to relativistic settings,” he says. He also cautions that no one knows which of the many tweaks to quantum mechanics is the correct one.

    Nonetheless, his model makes predictions that can be tested. For example, it predicts that gravity will behave differently at the scale of atoms from how it does on larger scales. Should those tests find that Tilloy’s model reflects reality and gravity does indeed originate from collapsing quantum fluctuations, it would be a big clue that the path to a theory of everything would involve semiclassical gravity.

    See the full article here .

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  • richardmitnick 11:17 am on May 25, 2017 Permalink | Reply
    Tags: , , , , Messier 87, New Scientist, Weird energy beam seems to travel five times the speed of light   

    From New Scientist: “Weird energy beam seems to travel five times the speed of light” 

    NewScientist

    New Scientist

    22 May 2017
    Joshua Sokol

    1
    Trick of the light. NASA and The Hubble Heritage Team (STScI/AURA)

    Please welcome to the stage a master illusionist. An energy beam that stabs out of galaxy Messier 87 like a toothpick in a cocktail olive is pulling off the ultimate magic trick: seeming to move faster than the speed of light [always means speed of light in a vacuum].

    Almost five times faster, in fact, as measured by the Hubble Space Telescope.

    NASA/ESA Hubble Telescope

    This feat was first observed in 1995 in galaxy Messier 87, and has been seen in many other galaxies since. It might have you questioning your entire reality. Nothing can break the cosmic speed limit, right? You can’t just flaunt the laws of physics… can you?

    If you want to just enjoy the illusion from your seat in the audience, stop reading. Otherwise, I welcome you backstage for a look at how the trick works – and how it’s helping astronomers to understand the fate of entire galaxies.

    Blobs faster than light?

    We’ve known about the jet of plasma shooting from the core of Messier 87 since 1918, when astronomer Heber Curtis saw a ray of light connected to the galaxy. To be visible from so far away, it had to be huge – about 6000 light years long.

    As modern astronomers now know, pretty much all galaxies have a central black hole that periodically draws in stars and gas clouds.

    Sag A* NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way

    When gas begins to swirl down the drain, it heats up and magnetic fields focus some of it into jets of hot plasma. These jets shoot out at velocities near to – but not faster than – the speed of light.

    If you were to aim a telescope into the sky towards Messier 87, you would see that this lance of plasma is askew. Instead of pointing exactly into our line of sight, it’s angled a bit to the right.

    To understand the illusion, picture a single glowing blob of plasma starting at the base of this path and emitting a ray of light, both of which travel towards Earth. Now wait 10 years. In that time, the blob has moved closer at a sizeable fraction of the speed of light. That gives the rays emitted from that later position a few light years’ head start on the way to us.

    If you compare the first and second images from Earth’s perspective, it looks like the blob has just moved across the sky to the right. But because the second position is also closer to us, its light has had less far to travel than it appears. That means it seems to have arrived there faster than it actually did – as if the blob spent those 10 years travelling at ludicrous speed.

    One among many

    The jet from Messier 87 is more than just a curiosity, says Eileen Meyer at the University of Maryland, Baltimore County.

    All over the universe, outflows of energy from massive black holes can stop or start the formation of stars throughout galaxies. But it’s unclear how these outflows work and how much energy they contain.

    By appearing to move faster than light, jets such as the Messier 87 one change visibly over just a few years, which is unusual for distant objects like galaxies. That allows astronomers to make precise estimates of how fast the plasma is moving and thus how powerful the process is.

    Messier 87 is special because it is relatively close compared to other galaxies, making it easy to study. In 1999, astronomers used Hubble pictures of the jet taken over four years to see that plasma ripple outwards. In 2013, Meyer lengthened that to 13 years of images, which seemed to show that the plasma might also be moving in corkscrew-like spirals – as if it wasn’t complicated enough.

    Fresh results from Meyer, now being prepared for publication, extend that baseline again to a total of more than two decades and may offer new surprises. “Over 20 years, you know, things go bump in the night,” she says.

    And although the faster-than-light effect is old hat to her, she still stops to appreciate it sometimes. Most things we see travelling across the sky, such as planets and comets, are close to us. But Messier87 is tens of millions of light years away. “We can see, over a human lifetime, things moving,” she says. “Which is crazy.”

    See the full article here .

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  • richardmitnick 8:05 am on March 30, 2017 Permalink | Reply
    Tags: , , , , New Scientist, Ticks on the march   

    From NS: “Lyme disease is set to explode, and you can’t protect yourself” 

    NewScientist

    New Scientist

    29 March 2017
    Chelsea Whyte

    A new prediction says 2017 and 2018 will see major Lyme disease outbreaks in new areas. This could lead to lifelong health consequences, so where’s the vaccine?

    1
    Tick tock. Mike Peres/Custom Medical Stock Photo/SPL

    BY THE time he had finished his walk through the woods in New York state, Rick Ostfeld was ready to declare a public health emergency. He could read the warning signs in the acorns that littered the forest floor – seeds of a chain of events that will culminate in an unprecedented outbreak of Lyme disease this year.

    Since that day in 2015, Ostfeld has been publicising the coming outbreak. Thanks to a changing climate it could be one of the worst on record: the ticks that carry the disease have been found in places where it has never before been a problem – and where most people don’t know how to respond. The danger zone isn’t confined to the US: similar signs are flagging potential outbreaks in Europe. Polish researchers predict a major outbreak there in 2018.

    In theory, Ostfeld’s early warning system gives public health officials a two-year window to prepare. In many other cases, this would be enough time to roll out a vaccination programme. But there is no human vaccine for Lyme disease. Why not? And what can you do to protect yourself in the meantime?

    Lyme disease is the most common infection following an insect bite in the US: the Centers for Disease Control estimates that 300,000 Americans contract Lyme disease each year, calling it “a major US public health problem”. While it is easy enough to treat if caught early, we are still getting to grips with lifelong health problems that can stem from not catching it in time (see “Do I have Lyme disease?“).

    This is less of a problem when Lyme is confined to a few small areas of the US, but thanks in part to warmer winters, the disease is spreading beyond its usual territory, extending across the US (see map) and into Europe and forested areas of Asia. In Europe in particular, confirmed cases have been steadily rising for 30 years – today, the World Health Organization estimates that 65,000 people get Lyme disease each year in the region. In the UK, 2000 to 3000 cases are diagnosed each year, up tenfold from 2001, estimates the UK’s National Health Service.

    So how could a floor of acorns two years ago tell Ostfeld, a disease ecologist at the Cary Institute of Ecosystem Studies in Millbrook, New York, that 2017 would see an outbreak of Lyme disease? It’s all down to what happens next.

    A bumper crop of the seeds – “like you were walking on ball bearings” – comes along every two to five years in Millbrook. Crucially, these nutrient-packed meals swell the mouse population: “2016 was a real mouse plague of a year,” he says. And mouse plagues bring tick plagues.

    Soon after hatching, young ticks start “questing” – grasping onto grasses or leaves with their hind legs and waving their forelegs, ready to hitch a ride on whatever passes by, usually a mouse.

    Gut reaction

    Once on board, the feast begins. Just one mouse can carry hundreds of immature ticks in their post-larval nymph stage.

    This is where the problems for us start. Mouse blood carries the Lyme-causing bacterium Borrelia burgdorferi, which passes to a tick’s gut as it feeds. The tick itself is unharmed, but each time it latches onto a new host to feed, the bacteria can move from its gut to the blood – including that of any human passers-by.

    “We predict the mice population based on the acorns and we predict infected nymph ticks with the mice numbers. Each step has a one year lag,” Ostfeld says.

    Ostfeld published his discovery of this chain of causation in 2006 [PLOS Biology]. Last year, researchers in Poland found the same trend there, with the same implications. “Last year we had a lot of oak acorns, so we might expect 2018 will pose a high risk of Lyme,” says Jakub Szymkowiak at Adam Mickiewicz University in Poznan, Poland.

    Those who live in traditional Lyme disease zones are well versed in tick awareness – wear long trousers in the woods, check yourself thoroughly afterwards, and more. But this advice will be less familiar in places that used to sit outside Lyme zones – like Poland. “That’s sort of the perfect storm,” says Ostfeld. “The public is unaware, so they’re not looking for it and they don’t get treated.”

    It’s not obvious when you have been bitten or infected: ticks are the size of a poppy seed, and not everyone gets the classic “bullseye” rash that is supposed to tip you off. The flu-like symptoms that follow are also easy to misdiagnose. And because antibodies to Lyme disease take a few weeks to develop, early tests can miss it. “That’s when you get late-stage, untreated, supremely problematic Lyme disease,” Ostfeld says.

    The best approach would be to vaccinate people at risk – but there is currently no vaccine. We used to have one, but thanks to anti-vaccination activists, that is no longer the case.

    In the late 1990s, a race was on to make the first Lyme disease vaccine. By December 1998, the US Food and Drug Administration approved the release of Lymerix, developed by SmithKline Beecham, now GSK. But the company voluntarily withdrew the drug after only four years.

    This followed a series of lawsuits – including one where recipients claimed Lymerix caused chronic arthritis. Influenced by now-discredited research purporting to show a link between the MMR vaccine and autism, activists raised the question of whether the Lyme disease vaccine could cause arthritis.

    Media coverage and the anti-Lyme-vaccination groups gave a voice to those who believed their pain was due to the vaccine, and public support for the vaccine declined. “The chronic arthritis was not associated with Lyme,” says Stanley Plotkin, an adviser to pharmaceutical company Sanofi Pasteur. “When you’re dealing with adults, all kinds of things happen to them. They get arthritis, they get strokes, heart attacks. So unless you have a control group, you’re in la-la land.”

    But there was a control group – the rest of the US population. And when the FDA reviewed the vaccine’s adverse event reports in a retrospective study, they found only 905 reports for 1.4 million doses. Still, the damage was done, and the vaccine was benched.

    After that, “no one touched it”, says Thomas Lingelbach, CEO at Valneva, a biotech company based in France. Until now: Valneva has a vaccine in early human trials. It will improve on Lymerix, acting against all five strains of the disease instead of just the one most common in the US, and it will be suitable for children.

    Lingelbach knows the battles his firm will face. “It will be hard to convince anti-vax lobbyists,” he says. That fight is still some way off: any public roll-out is at least six years away.

    What makes this wait especially galling for some is that there is a vaccine for your pet. “It’s ironic that you can vaccinate your animal and you can’t vaccinate yourself,” Plotkin says.

    In the animal vaccine, instead of exposing Fido to a weakened version of the antigen to trigger antibodies, it works within the tick, neutralising B. burgdorferi by altering the expression of a protein on the bacterium before it enters the bloodstream. This is how a human version would work. “The underlying scientific principle is not very far away from what it is in the veterinary environment,” says Lingelbach.

    Some people have suggested taking the animal vaccine, but Plotkin doesn’t recommend this as it hasn’t been tested in people so there is insufficient safety data. “You just don’t have classical efficacy data in humans,” he says. It is also illegal in the US and UK for vets to practise medicine on humans.

    While we wait for a human vaccine, you might start keeping track of your local acorn populations – but brush up on your anti-tick measures before you hit the woods.

    See the full article here .

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    • stbarbebaker 4:50 pm on March 30, 2017 Permalink | Reply

      Reblogged this on stbarbebaker and commented:
      Here is an intriguing article about ticks and Lyme disease. Get your tea tree oil and diatomaceous earth now before Easter arrives, around about when the ticks begin to show up.

      Like

  • richardmitnick 10:29 am on March 1, 2017 Permalink | Reply
    Tags: , , , New Scientist   

    From New Scientist: “If an asteroid hit London only 3% of deaths would be from impact” 

    NewScientist

    New Scientist

    24 February 2017
    Leah Crane

    1
    Chances are it won’t land anywhere near you. Getty

    Wind kills. The most casualties from an asteroid impact won’t come from the impact itself. The wind, pressure and heat caused by the crash are far more dangerous, no matter where the asteroid hits.

    Clemens Rumpf at the University of Southampton, UK, and his colleagues have calculated the mortality risk, should an asteroid hit a residential area. They considered asteroids that burn up completely, those that hit the ground, and those that strike in water. Surprisingly, the airborne side effects were the ones that cost the most lives.

    As an asteroid hurtles towards the ground, it deposits a huge amount of energy into the atmosphere, resulting in a powerful shockwave, tornado-like winds and a plume of fire trailing behind it. When it crashes down, it forms a crater, shaking the ground around the impact and hurling debris into the air.

    If the asteroid hits water (which is twice as likely as hitting land), it would create a tsunami, with waves reaching dozens of metres high. The farther from shore the impact is, the deeper the water and the taller the waves.

    Far-reaching effect

    In the past, people have shown that tsunamis posed the greatest risks from an asteroid impact, but the events are notoriously difficult to model. Rumpf and his colleagues have worked out that the continental shelf helps protect the shore by dissipating waves both at its steep edge and over its gentle beachward slope.

    “What sets tsunamis apart is that they’re really the most far-reaching effect of all the impact effects,” says Rumpf. A pressure wave or heat plume can’t travel very far, and craters only form right at the impact site, but tsunamis can traverse hundreds of kilometres of ocean to hit coastal communities.

    A tsunami caused by the impact of a 200-metre-wide asteroid 130 kilometres off the coast of Rio de Janeiro, for example, could cause more than 50,000 deaths, with 75 per cent of those being directly caused by the tsunami and the rest due to high winds.

    But an asteroid over or in a city would kill millions. Most of those deaths would be due to wind as well, even if the asteroid did crash to the ground instead of exploding in the air.

    For an airburst, about 15 per cent of casualties would come from heat. In a direct impact, the effects of gusting wind and surging temperatures are joined by pressure waves, which can rupture internal organs.

    Only about 3 per cent of casualties would be caused by the actual impact or the earthquakes and debris that result, says the team. The group plans to discuss the results with disaster managers to come up with suggestions for preparedness.

    Very rare events

    Luckily, large asteroids don’t hit Earth often: an impact by a 200-metre asteroid is expected only once every 40,000 years. And an asteroid could fall anywhere, and most of the planet’s surface is unpopulated.

    “Chances are that an asteroid hits the water, and even if it hits land it’s much more likely that it will hit away from populated regions,” says Rumpf. “These are very rare events, but with potentially high consequences.”

    In case you are starting to worry, there are lots of projects dedicated to planetary defence against asteroids: telescopes have spotted most of the big ones, and there are several potential ways to avoid an asteroid impact if we see it coming.
    “We are in the business of detecting asteroids well in advance of an impact, so this kind of work is only really important if we totally fail to do our jobs,” says Erik Christensen, director of the Catalina Sky Survey at the University of Arizona.

    Journal reference: arXiv:1702.05798

    See the full article here .

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  • richardmitnick 7:42 am on February 23, 2017 Permalink | Reply
    Tags: Accidental find, , New Scientist, ,   

    From New Scientist: “Far-off asteroid caught cohabiting with Uranus around the sun” 

    NewScientist

    New Scientist

    16 February 2017
    Ken Croswell

    1
    Now with added Trojans. NASA/Erich Karkoschka (Univ. Arizona)

    A rare Trojan asteroid of Uranus has been found, following the same orbit as the planet. Its existence implies there could be many more of these companion asteroids, and that they are more common than we thought.

    A Trojan asteroid orbits the sun 60 degrees ahead of or behind a planet. Jupiter and Neptune have numerous Trojans, many of which have been in place for billions of years. These primordial rocks hold information about the solar system’s birth, and NASA has just announced plans to visit several of them in the 2020s and 2030s.

    But Saturn and Uranus live in a rougher neighbourhood: the giant planets on either side of them yank Trojans away through their gravitational pull. So Saturn has no known Trojan, and Uranus had only one.

    In July, though, astronomers reported a new asteroid, named 2014 YX49, that shares Uranus’s orbital period of 84 years. Now computer simulations of the solar system by brothers Carlos and Raul de la Fuente Marcos at the Complutense University of Madrid, Spain, indicate the asteroid is a Uranus Trojan. The simulations show that the asteroid has maintained its position ahead of Uranus for thousands of years.

    “It is bigger, probably twice as big as the first one,” says Carlos. The new asteroid is brighter than the first, but its exact size depends on how much light its surface reflects. If it reflects half the sunlight striking it, it’s 40 kilometres across; if it reflects 5 per cent, its diameter is 120 kilometres.

    Accidental find

    The new asteroid was found by accident, which Carlos says implies there should be more waiting to be discovered. He thinks its Trojans could number in the hundreds.

    Unlike the Trojans of Jupiter and Neptune, the simulations suggest that the two known Uranus Trojans are transient rather than permanent. Carlos suspects Uranus lacks primordial Trojans because the other giant planets kicked them away.

    The simulations indicate that the new asteroid was once a centaur, an object that skirts between the orbits of the giant planets. About 60,000 years ago, buffeted by their gravitational tugs, it was caught ahead of Uranus in its orbit around the sun and became a Trojan; it is likely to remain so for another 80,000 years, before eventually becoming a centaur again.

    Although Carlos thinks Uranus has no permanent Trojans, David Jewitt at the University of California at Los Angeles is willing to wait and see. “In the end the answer will come — as always — from observations,” he says. “People will either find permanent Uranus Trojans or not.”

    And Saturn? “The neighbourhood of Saturn is even more chaotic than that of Uranus,” Carlos says, due to Jupiter’s proximity. Still, he thinks Trojans of Saturn could exist.

    Journal references: Monthly Notices of the Royal Astronomical Society and ArXiv, arxiv.org/abs/1701.05541

    See the full article here .

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  • richardmitnick 4:13 am on December 29, 2016 Permalink | Reply
    Tags: a third of way to Earth’s core, Deepest water found 1000km down, New Scientist,   

    From Northwestern via New Scientist: “Deepest water found 1000km down, a third of way to Earth’s core” 

    Northwestern U bloc
    Northwestern University

    NewScientist

    New Scientist

    23 November 2016 [Hidden under a rock under a lake]
    Andy Coghlan

    1
    Priceless imperfection. Mederic Palot

    JULES VERNE’s idea of an ocean deep below the surface in Journey to the Centre of the Earth may not have been too far off. Earth’s mantle may contain many oceans’ worth of water – with the deepest 1000 kilometres down.

    “If it wasn’t down there, we would all be submerged,” says Steve Jacobsen at Northwestern University in Evanston, Illinois, whose team made the discovery. “This implies a bigger reservoir of water on the planet than previously thought.”

    This water is much deeper than any seen before, at a third of the way to the edge of Earth’s core. Its presence was indicated by a diamond spat out 90 million years ago by a volcano near the São Luíz river in Juina, Brazil.

    The diamond has an imperfection – a sealed-off inclusion – that contains minerals that became trapped during the diamond’s formation. When the researchers took a closer look at it with infrared microscopy, they saw unmistakable evidence of the presence of hydroxyl ions, which normally come from water. They were everywhere, says Jacobsen.

    To work out the depth the diamond formed at – and hence the origins of this water – the team again turned to the inclusion. It is made of a ferropericlase mineral, which is composed of iron and magnesium oxide, and can also absorb other metals such as chromium, aluminium and titanium at ultra-high temperatures and pressures typical of the lower mantle.

    Jacobsen found that these additional metals had separated from the ferropericlase – something that happens in the milder conditions a diamond experiences as it edges up through shallower depths. But for the metals to be present at all, the diamond must have originated in the intense conditions of the lower mantle (Lithos, doi.org/btcn). “Based on the composition of the trapped mineral, we speculate that the depth was around 1000 kilometres,” says Jacobsen.

    The clincher is that as the inclusion was trapped in the diamond the whole time, the water signature can only have come from the diamond’s place of formation in the lower mantle. “This is the deepest evidence for water recycling on the planet,” he says. “The big take-home message is that the water cycle on Earth is bigger than we ever thought, extending into the deep mantle.”

    His team has previously found evidence of massive amounts of water some 600 kilometres down, mixed in with rock.

    “Water clearly has a role in plate tectonics, and we didn’t know before how deep these effects could reach,” he says. “It has implications for the origin of water on the planet.” For example, it is possible that Earth had water from day one in the very dust and rocks that first formed it.

    But it’s still not clear exactly how water got so far down. It may have arrived in the mantle even earlier than 90 million years ago, through sedimentary oceanic crust burrowing downwards as primitive tectonic plates thrust against and past each other.

    The new study suggests cycling of subducted material, even at these depths, says Lydia Hallis at the University of Glasgow, UK. “Ultimately, this research will help us better understand the way our planet recycles itself.”

    Jacobsen thinks that this water may help explain why Earth is the only planet we know to have plate tectonics. “Water mixes with ocean crust and gets subducted at convergent plate boundaries,” he says. “Introducing water into the mantle promotes melting and weakens rock, likely helping out the motions of plates like grease.”

    The hope is that such research will yield insights into how our oceans and atmosphere formed in the first place.

    See the full article here .

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    Northwestern South Campus
    South Campus

    On May 31, 1850, nine men gathered to begin planning a university that would serve the Northwest Territory.

    Given that they had little money, no land and limited higher education experience, their vision was ambitious. But through a combination of creative financing, shrewd politicking, religious inspiration and an abundance of hard work, the founders of Northwestern University were able to make that dream a reality.

    In 1853, the founders purchased a 379-acre tract of land on the shore of Lake Michigan 12 miles north of Chicago. They established a campus and developed the land near it, naming the surrounding town Evanston in honor of one of the University’s founders, John Evans. After completing its first building in 1855, Northwestern began classes that fall with two faculty members and 10 students.
    Twenty-one presidents have presided over Northwestern in the years since. The University has grown to include 12 schools and colleges, with additional campuses in Chicago and Doha, Qatar.

    Northwestern is recognized nationally and internationally for its educational programs.

     
  • richardmitnick 1:48 pm on December 13, 2016 Permalink | Reply
    Tags: , New Scientist,   

    From New Scientist: “Quantum computers ditch all the lasers for easier engineering” 

    NewScientist

    New Scientist

    7 December 2016
    Michael Brooks

    1
    Lasers are not the only option. Richard Kail/Science Photo Library

    They will be the ultimate multitaskers – but quantum computers might take a bit of juggling to operate. Now, a team has simplified their inner workings.

    Computers that take advantage of quantum laws allowing particles to exist in multiple states at the same time promise to run millions of calculations at once. One of the candidate technologies involves ion traps, which hold and manipulate charged particles, called ions, to encode information.

    But to make a processor that works faster than a classical computer would require millions of such traps, each controlled with its own precisely aligned laser – making it extremely complicated.

    Now, Winfried Hensinger at the University of Sussex in the UK and his colleagues have replaced the millions of lasers with some static magnets and a handful of electromagnetic fields. “Our invention has led to a radical simplification of the engineering required, which means we are now able to construct a large-scale device,” he says.

    In their scheme, each ion is trapped by four permanent magnets, with a controllable voltage across the trap. The entire device is bathed in a set of tuned microwave and radio-frequency electromagnetic fields. Tweaking the voltage shifts the ions to a different position in the magnetic field, changing their state.

    Promising technology

    The researchers have already used this idea to build and operate a quantum logic gate, a building block of a processor. This particular gate involves entangling two ions – in other words, linking their quantum states such that they are fully dependent on each other. Hensinger says this is the most difficult kind of logic gate to build.

    Manas Mukherjee at the National University of Singapore is impressed with the new technology. “It’s a promising development, with good potential for scaling up,” he says.

    That’s exactly what the team is planning: they hope to have a trial device containing tens of ions ready within four years.

    The fact that the device uses current technologies such as techniques for silicon-chip manufacturing means there are no known roadblocks to scaling up to create a useful quantum computer.

    It won’t be plain sailing, though. Scaling up will mean creating magnetic fields that vary in strength over relatively short distances. This a significant engineering challenge, says Mukherjee. Then there’s the challenge of handling waste heat, which becomes more problematic as the processor gets bigger. “As with any architecture, you need low heating rates,” he says.

    Journal reference: Physical Review Letters, DOI: 10.1103/PhysRevLett.117.220501

    See the full article here .

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