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  • richardmitnick 2:22 pm on December 6, 2019 Permalink | Reply
    Tags: "Two of the biggest US earthquake faults might be linked", Cascadia fault, , , NATURE,   

    From Nature: “Two of the biggest US earthquake faults might be linked” 

    Nature Mag
    From Nature

    05 December 2019

    1
    The earthquake that devastated San Francisco, California, in 1906 arose from the San Andreas fault — which might be linked to another major fault zone to the north.Credit: Underwood Archives/Getty

    Two of North America’s most fearsome earthquake zones could be linked.

    A controversial study argues that at least eight times in the past 3,000 years, quakes made a one–two punch off the west coast of the United States. A quake hit the Cascadia fault off the coast of northern California, triggering a second quake on the San Andreas fault just to the south. In some cases, the delay between the quakes may have been decades long.

    The study suggests that Cascadia, which scientists think is capable of unleashing a magnitude-9 earthquake at any time, could set off quakes on the northern San Andreas, which runs under the San Francisco Bay Area.

    Several earthquake scientists told Nature that more work is needed to confirm the provocative idea. Researchers have long considered the two faults seismically separate.

    Chris Goldfinger, a geologist and palaeoseismologist at Oregon State University in Corvallis, will present the findings on 13 December at a meeting of the American Geophysical Union in San Francisco. “This is mostly a circumstantial case,” he says. “I don’t have a smoking gun.”

    Tantalizing clues

    Goldfinger and his colleagues first suggested in 2008 that earthquakes in the southern part of Cascadia could trigger quakes on the northern San Andreas [1]. The scientists reported finding layers of churned-up, sandy sediment in sea-floor cores drilled offshore. These layers, called turbidites, usually form when earthquakes shake the sea floor, causing underwater landslides. The researchers reported finding turbidites in Cascadia that seemed to form just before similar turbidites near the San Andreas — perhaps as a Cascadia quake triggered a San Andreas one.

    But it was hard to pinpoint exactly when the turbidites had formed, and Goldfinger knew he needed more evidence. “So that’s what we did,” he says. “We went out and got more cores.”

    Now he has data from seven cores drilled offshore in southern Cascadia and seven cores drilled near the northern San Andreas. The two sites are around 100 kilometres apart — close enough to feel shaking from both faults.

    At eight places in both sets of cores, Goldfinger spotted unusual, two-layered turbidites and realized that they were telling him something new. “Finally the lights went on for me,” he says. The two-layered turbidite “has to be two quakes recorded together”.

    Doubts remain

    As Goldfinger sees it, a Cascadia quake shook the coastline first, causing landslides that show up in both sets of cores as the first layer of turbidites. Then, at some later point, the northern San Andreas also shook, causing the second turbidite layer to form.

    “This story is pretty convincing,” says Jason Patton, an engineering geologist with the California Geological Survey in Sacramento who was a co-author on the 2008 paper. “Cascadia turbidites are covered by San Andreas turbidites, so the Cascadia turbidites were deposited first.”

    Others are reserving judgement. Turbidites show that the ground shook at some point in the past, but it’s difficult to tell exactly when or where those quakes happened, says Joan Gomberg, a seismologist at the US Geological Survey in Seattle, Washington. “All this uncertainty leaves multiple, equally plausible interpretations on the table — most of which are not sensational,” she says. For instance, the turbidites could have been formed by unrelated quakes happening anywhere across the seismically active Pacific Northwest.

    Ross Stein, a seismologist with the earthquake-preparedness firm Temblor in Redwood City, California, wants to see detailed modelling of how stress from the Cascadia fault might be transferred to the northern San Andreas. Researchers generally agree that a large earthquake can sometimes trigger another on a nearby fault, by transferring stress and bringing the second fault closer to failure. But it’s not clear whether that might happen between southern Cascadia and the northern San Andreas, Stein says.

    Next week at the conference, Goldfinger says, “I’m just going to lay out the case.”

    References

    1.

    Goldfinger, C. et al. Bull. Seismol. Soc. Am. 98, 861–889 (2008).

    See the full article here .

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 4:09 pm on November 30, 2019 Permalink | Reply
    Tags: "Five ways China must cultivate research integrity", , , NATURE   

    From Nature: “Five ways China must cultivate research integrity” 

    Nature Mag
    From Nature

    26 November 2019

    A swift increase in scientific productivity has outstripped the country’s ability to promote rigour and curb academic misconduct; it is time to seize solutions.

    1
    A researcher stacks mouse containers at an animal-breeding facility near Guangzhou, China. Credit: Qilai Shen/Bloomberg/Getty

    How researchers in China behave has an impact on the global scientific community. With more than four million researchers, China has more science and technology personnel than any other nation. In 2008, it overtook the United Kingdom in the number of articles indexed in the Web of Science, and now ranks second in the world. In 2018, China published 412,000 papers.

    But China also produces a disproportionate number of faked peer reviews and plagiarized or fraudulent publications. Its share of retracted papers is around three times that expected from its scientific output (see ‘Outsized retractions’).

    The past few years have witnessed high-profile cases of faked peer reviews, image manipulations and authorships for sale, some involving prominent Chinese scientists. In May last year, China asked two groups to foster research integrity and manage misconduct cases: its Ministry of Science and Technology (MOST) and the Chinese Academy of Social Sciences (CASS) . In November 2018, 41 national government agencies endorsed a set of 43 penalties for major academic misconduct. These range from terminating grants to restricting academic promotion and revoking business licences. This year, the government issued a foundational document to promote the scientific enterprise and foster a culture of academic integrity [1].

    China’s strides towards reform have been well received domestically and abroad, but effecting lasting change is hard [2]. To better characterize the situation, my team has studied global retraction data alongside national grants and applications that were revoked. We also surveyed researchers online and interviewed major stakeholders in China [3],[4]. These included experts on university ethics committees, programmes for research-integrity training and plagiarism detection, as well as funding-programme managers, journal editors and academics. Here, I outline major challenges in research integrity, and potential strategies and solutions to buttress it.

    2
    Source: L. Tang/Web of Science

    Five strategies

    Align norms. What counts as misconduct rather than acceptable practice differs across cultural settings and disciplines. The lack of consensus over what misconduct means is a thorny challenge for an emerging scientific powerhouse. One of our interviewees noted that senior academics even disagreed over what constitutes an allegation.

    Any discussion about misconduct and penalties is buffeted by conflicting norms: historical versus the present, national versus international. For example, the reuse of text without proper citation is, to some degree, accepted in textbook publishing in China. Until 1999, duplicate submissions or even dual publication in Chinese and English were not considered particularly inappropriate. More than 20% of our survey respondents felt that duplicate submission and self-plagiarism were common in their domain. These are deemed misconduct in international scientific communities.

    That presents Chinese scientific leaders with a dilemma: if wrongdoing is not punished, the scientific community could become more tolerant, and there might be more misconduct and recidivism. That would waste public money, erode trust in science and tarnish the country’s reputation. Already, Chinese academics can find it difficult to maintain or expand international collaborations, and universities and funding agencies outside China have ethical concerns about forming partnerships.

    But requiring strict compliance with international norms would target a broad spectrum of misbehaviours that are common practice. And high standards with unworkable rules could legitimize non-compliance [5]. Either scenario could stymie reform.

    Optimize approaches. Research misbehaviour needs to be policed. Strategies can be classed as ‘patrols’ or ‘fire alarms’ [6]. Like other countries, China deploys both.

    On the patrol side, China National Knowledge Infrastructure (CNKI), a Chinese version of the Web of Science database, provides a plagiarism-checking service to Chinese journals and universities. These have deployed CNKI software to detect plagiarized texts, including those saved as manipulated images. Since 2010, grant proposals have been checked for possible plagiarism at the National Natural Science Foundation of China (NSFC). Similarly, the National Social Science Fund of China (NSSFC) instigates systematic clean-ups for its funded projects, halting those that are left unfinished after the completion deadline (typically six years after receiving the grant). This put an end to 302 of 5,035 grants funded from 2002 to 2005. Terminated projects increased from 60 in 2002 to 99 in 2005, but have plummeted since checks were implemented and publicized in 2012 (ref. 3; see ‘Checks changed behaviour’).

    3
    Source: NSSFC

    Patrol deters certain types of misconduct, particularly before a grant or degree is awarded or a paper accepted. But patrols require dedicated software and infrastructure, so are costly to enforce. Every May (just before graduation), college students, university faculty members and support staff spend hours checking theses for plagiarism.

    Perhaps that is why a fire-alarm tactic is dominant. China’s science agencies and universities often wait to act until contacted by the media, wronged parties or whistle-blowers, and they focus most on cases that grab headlines. This can be effective in the short term: in 2017, after 107 articles by Chinese authors were retracted by the journal Tumor Biology for faked peer reviews, investigations were completed within 4 months. More than 100 people were penalized and some 40 NSFC grants revoked. But the fire-alarm tactic leads to selective investigations and uncertainty. It punishes past offences, but does little to deter future ones.

    Empower enforcement. The burden of policing misconduct is too much for national agencies in any country, China included. That power is delegated to the universities and institutes where researchers work. But these organizations, concerned about soiling reputations and losing grant funds, are often unwilling to investigate alleged misconduct. They tend to respond only when whistles are blown. That depends on whistle-blowers who shoulder great professional and personal risk, especially in Chinese society, which values collectivism and interdependence over individualism and independence. In a 2017 survey of Chinese scholars, more than half of respondents who observed misconduct in the past three years said that they did nothing about it (unpublished results; see also Supplementary Information).

    Assign responsibility. Perhaps the most difficult challenge in China, as elsewhere, is whether and to what extent to hold team members accountable for misconduct in joint work. Increasing specialization and globalization has made collaborations larger and more essential. That complicates how to allocate blame as well as credit. Should each listed author be held accountable for the full work, or just for their own? Should the corresponding author take most of the responsibility for fraud and errors others committed? Although more journals are requiring detailed descriptions of authors’ contributions, discerning who should be responsible for a collaborative piece of work is difficult. This is particularly true when older articles are retracted as a result of proven fraud — often, author contributions have not been specified.

    The supervisor–student relationship poses a particular dilemma. In China, when PhD students are found guilty of misconduct, their supervisors are also punished. In recent scandals, plagiarists were stripped of their doctoral degrees, and their supervisors were demoted and barred from taking on PhD candidates. Alternatively, junior scientists might be punished, while senior ones responsible for misconduct retain status and position. Some argue that holding members of a research team accountable by association will improve enforcement and prevent scapegoating; others say that this shift in responsibility is unfair and burdensome.

    Cultivate integrity. China’s rapid research development must be brought into sync with a culture of integrity. Like other countries, it has seen that tying publication requirements to degree requirements, promotion or monetary rewards can lure researchers into inappropriate behaviour [7].

    Integrated tactics

    What is the best way to implement these strategies? I propose that working on several fronts will make each easier to accomplish.

    Forgive, then be tough. China’s scientific community first needs to agree on a common code of academic integrity that defines misconduct and undesirable research practices and sets out sanctions. China has a greater diversity of funders and a more mobile scientific workforce than ever before, so all stakeholders — including researchers, managers, journal editors and funding officers — must be in accord.

    Penalties should focus on the most egregious acts, which are universally recognized: falsification, fabrication, plagiarism and fake reviews. Researchers should be admonished for past fraud but face harsher penalties for incidents that occur once the code is in place. Less serious questionable practices that were historically accepted should be subject to a statute of limitations.

    Institutionalize. Integrity must be built into scientific institutions, with MOST and CASS taking the lead. CASS should set up departments to oversee misconduct cases, as MOST has. Both agencies should facilitate communication between all stakeholders and coordinate input from research societies to formulate workable rules that are compatible with international norms.

    Transparency will help. Funding agencies should, for example, publicize the claimed achievements and promised research outputs of award recipients in prestigious talent programmes. This accountability will deter fraud and false advertising. China’s General Administration of Press and Publications can help by urging Chinese publishers and database providers to take a proactive stance. For instance, Chinese journals often simply remove retracted articles from their collections and the CNKI database. Instead, journals should explicitly mark articles as retracted, as many Western journals do [8]. They should also share their ‘blacklists’ of authors who have repeatedly been found guilty of duplicate submissions.

    With the right support, universities and research institutes can be best placed to initiate misconduct investigations. MOST and CASS should help them set up procedures. These should include appointing an independent ombudsperson to protect whistle-blowers and those accused of misconduct, for example by developing strategies to prevent cyberbullying and smear campaigns. In addition, each university should employ a professional chief integrity officer — not a faculty ‘volunteer’ — who reports directly to a vice-president.

    Incentivize. Administrative agencies must explicitly link support for a university to whether it vigorously investigates misconduct allegations and promotes integrity education, including putting dedicated professionals in place. Agencies can also set up open, regular communication about reform with junior and senior researchers — for real-world input and to allow institutions to learn from each other.

    Educate. A healthy academic atmosphere cannot be built on penalties for misbehaviour alone. Universities could set up research-integrity help desks and hotlines, making contact information and investigation procedures accessible. The Chinese university code of academic integrity should be linked from every course syllabus. Teachers should have access to plagiarism-checking software and to training so they can understand its shortcomings.

    More broadly, universities must work out how to provide effective integrity education. Training upstream is always better than disciplining transgressors after the fact (see also go.nature.com/2rpdhkv).

    Many Chinese universities now require graduate students to take responsible-conduct courses. Around three-quarters of our survey respondents said they had received training in research ethics and integrity. Those enrolling for a PhD at Fudan University in Shanghai, for example, must attend mandatory ethics modules. Only those who pass the ethics quiz can register for further coursework.

    Such training needs to be universal across Chinese institutions, and at all levels: for faculty members, technicians and non-scientific staff. Principal investigators who coordinate collaborations, as well as young researchers who collect, check and validate data, must know and accept their responsibilities4. ‘Trust and verify’ should be bywords for all. For example, at least two team members should collect and code raw data and record source links and detailed procedures. Pre-registration of analysis plans could also prevent tampering [9].

    Study. Also needed is rigorous research on what kind of institutional structures and programmes foster integrity, which types of training effect the most lasting change, and how to apply best practice. Comparative studies could provide lessons from other countries that have experience in combating academic misconduct and cultivating integrity. For example, in 2014, Denmark adopted a new code of conduct for research integrity as a result of orchestrated efforts by researchers, funding agencies and other stakeholders. The Netherlands followed suit in 2018. Indian efforts against predatory publishing could be adapted for China, as could the long-established US emphasis on quality rather than quantity in research evaluation.

    To gather this knowledge, oversight agencies should have an open-door policy for stakeholders to express constructive and diverse opinions. Proceedings of misconduct investigations should be made public, not be shrouded in secrecy [10]. Funding agencies need to earmark money for research-integrity studies to attract bright minds to the field. This year, the NSFC issued an open call for proposals on research integrity and ethics; it is unclear whether such funds will be available in future.

    China must curb misconduct and foster integrity if it is to realize the central government’s ambition of “world-class universities, world-class disciplines”. It is still too early to anticipate all the changes reforms will bring, but the government has signalled its determination to act. We might see more investigations of misconduct because of closer scrutiny in the next couple of years. Improving the research practices of Chinese scholars will boost innovation and development everywhere.

    How researchers in China behave has an impact on the global scientific community. With more than four million researchers, China has more science and technology personnel than any other nation. In 2008, it overtook the United Kingdom in the number of articles indexed in the Web of Science, and now ranks second in the world. In 2018, China published 412,000 papers.

    But China also produces a disproportionate number of faked peer reviews and plagiarized or fraudulent publications. Its share of retracted papers is around three times that expected from its scientific output (see ‘Outsized retractions’).

    The past few years have witnessed high-profile cases of faked peer reviews, image manipulations and authorships for sale, some involving prominent Chinese scientists. In May last year, China asked two groups to foster research integrity and manage misconduct cases: its Ministry of Science and Technology (MOST) and the Chinese Academy of Social Sciences (CASS) . In November 2018, 41 national government agencies endorsed a set of 43 penalties for major academic misconduct. These range from terminating grants to restricting academic promotion and revoking business licences. This year, the government issued a foundational document to promote the scientific enterprise and foster a culture of academic integrity1.

    China’s strides towards reform have been well received domestically and abroad, but effecting lasting change is hard2. To better characterize the situation, my team has studied global retraction data alongside national grants and applications that were revoked. We also surveyed researchers online and interviewed major stakeholders in China3,4. These included experts on university ethics committees, programmes for research-integrity training and plagiarism detection, as well as funding-programme managers, journal editors and academics. Here, I outline major challenges in research integrity, and potential strategies and solutions to buttress it.

    China must curb misconduct and foster integrity if it is to realize the central government’s ambition of “world-class universities, world-class disciplines”. It is still too early to anticipate all the changes reforms will bring, but the government has signalled its determination to act. We might see more investigations of misconduct because of closer scrutiny in the next couple of years. Improving the research practices of Chinese scholars will boost innovation and development everywhere.

    References [See the original article for links to references.]

    1.

    General Offices of the Communist Party of China Central Committee and the State Council. [in Chinese] ‘Opinions on Further Promoting the Spirit of Scientists and Strengthening the Style of Work and Study Style’ (CPC Central Committee & State Council, 2019); available at https://go.nature.com/2d29xhj
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    Lei, R., Zhai, X., Zhu, W. & Qiu, R. Nature 569, 184–186 (2019).
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    See the full article here .

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  • richardmitnick 12:08 pm on July 31, 2018 Permalink | Reply
    Tags: , , NATURE   

    From Nature: “Ideal witness: a physicist takes on the world” 

    Nature Mag
    From Nature

    30 July 2018

    Robert P. Crease enjoys Steven Weinberg’s rationalist view of science and its history.

    1
    Part of the ring tunnel at the Large Hadron Collider near Geneva, Switzerland.Credit: Thomas Pflaum/VISUM/eyevine

    Third Thoughts Steven Weinberg Belknap (2018)

    In his 1974 book The First Three Minutes (1977), physicist and Nobel laureate Steven Weinberg pictured his ideal reader as “a smart old attorney” who might not know much science, but “expects nonetheless to hear some convincing arguments”. That’s still his approach in Third Thoughts. This essay collection (his third for a lay readership, hence the title), ranges widely over science, the history of science and current affairs, taking on everything from dark energy and quantum field theory to socio-economic inequity and the wastefulness of crewed space missions.

    Steven Weinberg, U Texas, Larry D. Moore CC BY-SA 3.0., https://en.wikipedia.org/wiki/File:Steven_weinberg_2010.jpg

    The volume mixes new pieces with others previously published in The New York Review of Books. Weinberg acknowledges the help he received from the review’s formidable editor, the late Robert Silvers. He clearly apprenticed well: if his ideal reader is an astute lawyer, Weinberg might be described as an ideal witness. He is clear, to the point, frank and transparent about his perspective — “rationalist, realist, reductionist, and devoutly secular”.

    Among half a dozen pieces on particle physics are lucid explications of, for instance, the Higgs boson, Hilbert space and the Large Hadron Collider. Weinberg has a knack for capturing a complex concept in a succinct, unforgettable image. He compares quantum superposition, in which a particle has two states at once, to a musical chord; when measurement collapses the particle to one state, it “somehow shifts all the intensity of the chord to one of the notes, which we then hear on its own”. And he describes the discovery that nature obeys symmetries whose consequences can be worked out as “like having a spy in the enemy’s high command”.

    A few of the essays delve into history. Weinberg has irked professionals in the field by venturing into their territory, but not because he gets his facts wrong. As a self-confessed ‘Whig’ historian, he believes that the past should be judged by values of the present (the term springs from the name of the long-defunct British political party whose members thought history had been building towards Parliamentary government). Weinberg offers a curious panorama that demotes certain canonical figures, such as Democritus, Francis Bacon and René Descartes.

    The ancient Greek philosopher Democritus didn’t make observations, so, although he correctly proposed that matter is made of atoms, Weinberg argues that he “was wrong about how to learn about the world”. Yet Democritus is of supreme importance for the understanding of science history (as Weinberg admits) because he inspired atomic theorists of the early modern period, such as Robert Boyle and other corpuscular philosophers, in their efforts to explain nature without using theology or teleology. Similarly, Bacon and Descartes, although sometimes scientifically misguided by today’s standards, were vastly important for ushering in the mechanical thinking that Weinberg himself practises. Two essays here convey Weinberg’s responses to critics of his Whig convictions, but I wish he had put the arguments and counter-arguments more forcefully and at greater length.

    Weinberg is at his most interesting when probing the big uncertainties in physics. Ultimately, he is not sure, for instance, that he knows what an ‘elementary particle’ actually is, or how best to interpret quantum mechanics. These moments reveal Weinberg’s considerable integrity, where — as one of the smartest and most diligent scientists around — he describes himself as somewhat lost. He has surveyed the present, and all the best paths forward proposed by other scientists; yet, at gut level, he is confident that nothing on the horizon is fully satisfactory, and that other possibilities might be out there. These admissions imply that Weinberg suspects future historians may harbour a perception of today’s thinking very different from ours.

    The articles on public and personal matters — Weinberg’s thoughts about taxes, his disappointment with former US President Barack Obama for failing to confront economic disparities more directly, and educators who are honoured with burial in Texas State Cemetery — are less interesting. Yet here, as elsewhere, he is clever: “The only technology for which the manned space flight program is well suited is the technology of keeping people alive in space. And the only demand for that technology is in the manned space flight program itself.”

    I read the penultimate essay with anticipation. Weinberg reveals in the introduction that he had not published it before because nobody who read it liked it. You can see why. It’s an earnest piece of amateur philosophizing that compares creativity in theoretical physics to that in the arts, building on Weinberg’s feeling that success in each depends on “a sense of inevitability”. He would have been clearer had he consulted a few philosophical concepts, such as Immanuel Kant’s idea that a beautiful work creates the feeling that it has the inevitability of a product of nature. But Weinberg (whose 1992 book Dreams of a Final Theory contains a chapter entitled ‘Against Philosophy’) was not about to take that route. In all these essays, his directness both enlightens and illuminates flaws in his own arguments. Witnesses, of course — even ideal ones — have blind spots. The best thing about Weinberg’s essays is that they do, indeed, make you feel like a smart old attorney.

    See the full article here .

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  • richardmitnick 11:07 am on November 15, 2017 Permalink | Reply
    Tags: , But scientists contacted by Nature have raised concerns about CSNS’s location saying that Dongguan lacks services and infrastructure such as schools and universities that will persuade top scientist, China fires up next-generation neutron-science facility, NATURE, , , Spallation neutron sources produce neutrons by slamming protons onto a metal target — CSNS uses tungsten   

    From Nature: “China fires up next-generation neutron-science facility” 

    Nature Mag
    Nature

    14 November 2017
    David Cyranoski

    Beam generator puts country in elite company for doing experiments in materials science and other fields.

    1
    Engineers work on an instrument at the China Spallation Neutron Source in Dongguan. Jin Liwang/Xinhua via ZUMAPRESS

    China is revving up its next-generation neutron generator and will soon start experiments there. That will lift the country into a select group of nations with facilities that produce intense neutron beams to study the structure of materials.

    The China Spallation Neutron Source (CSNS) in Dongguan, a 2.2-billion-yuan (US$331-million) centre, will allow the country’s growing pool of top-notch physicists and material scientists, along with international collaborators, to compete in multiple physics and engineering fields. Its designers also hope that the facility will lead to commercial products and applications ranging from batteries and bridges to aeroplane engines and cancer therapy.

    “It is not only a big step forward for Chinese scientists, but also a significant event for the international scientist community,” says Wang Xun-Li, a physicist at the City University of Hong Kong who has been involved in planning the facility.

    Beam bombardment

    Spallation neutron sources produce neutrons by slamming protons onto a metal target — CSNS uses tungsten. They are more cost effective and safer than other methods, which use nuclear reactors to produce neutron beams. As neutrons have no charge, they can penetrate materials more easily than some other probing methods, and they are more senstive to light elements such as hydrogen, making them useful for evaluating candidate materials for fuel cells. Similar facilities exist only in the United Kingdom, United States, Japan and Switzerland, and one is under construction in Sweden.

    Fujio Maekawa, a specialist in neutron sources at the Japan Proton Accelerator Research Complex in Tokaimura, says that although the CSNS delivers neutrons at a lower density than other spallation sources — which means that experiments will take longer — a planned upgrade will bring it in line with other facilities. And given their scarcity, “neutron users around the world always welcome new sources”, he says.

    The CSNS will have capacity to host 20 beam lines, supplying as many instruments. Preliminary tests of its first three instruments began on 1 November. “Neutrons arrived at the samples as expected,” says Wang Fangwei, head of the neutron-science division at CSNS. Although debugging might take a couple of years, he expects the instruments to be calibrated and ready for initial experiments by the end of 2017.

    Chinese physicists are eager to use the facility to analyse the underlying magnetic properties of materials, an area in which the country has significant experience. Wang Xun-Li says that several planned instruments will give scientists the chance to move to the forefront of fields such as the physics of skyrmions — vortex-like excitations in magnetic materials — and high-temperature superconductivity. “There are a whole bunch of early- to mid-career scientists who are hungry to use the facility for studying magnetism,” says Wang Xun-Li.

    Global appeal

    Wang Xun-Li thinks that the latest facility will encourage Chinese researchers to remain in the country instead of pursuing careers elsewhere. “In the past, it was common to see Chinese scientists go abroad for these kinds of studies,” he says.

    The facility’s first instruments are also attracting international researchers. German material scientist Frank Klose says that the CSNS was a major factor when he and material scientist Christine Rehm, his wife, decided to join the new Guangdong Technion Israel Institute of Technology in Shantou, 400 kilometres east of Dongguan. Klose’s research focuses on designing data-storage devices and sensors that could be used in hydrogen-powered cars. He helped design one of the facility’s instruments to investigate the magnetic properties of spintronic devices, which take advantage of the spin of electrons to store data.

    But scientists contacted by Nature have raised concerns about CSNS’s location, saying that Dongguan lacks services and infrastructure, such as schools and universities, that will persuade top scientists and their families to move there. “I believe CSNS is suffering from a lack of first-grade scientists who actually are based in Dongguan,” says a researcher familiar with the facility, who asked for anonymity because of the sensitivity of the issue. Potential users have also expressed some frustration that only 3 instruments will be ready this year, despite the facility’s capacity to host 20.

    But more instruments are already being built. Shenzhen’s government is funding two that are expected to be ready by the end of 2019, including one designed to model high-pressure environments, such as the Earth’s core. Mao Ho-Kwang, a geophysicist at the Carnegie Institution for Science in Washington DC, is keen to use it to simulate what happens to materials in high-pressure conditions. “The CSNS instruments will be a great asset for Earth, environmental and energy science, as well as physics, chemistry and material science,” says Mao. “I am very excited, and the whole neutron community is getting very excited too”.

    See the full article here .

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    STEM Icon

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 12:59 pm on November 1, 2017 Permalink | Reply
    Tags: Astronomers race to learn from first interstellar asteroid ever seen, , , , , NATURE   

    From Naure: “Astronomers race to learn from first interstellar asteroid ever seen” 

    Nature Mag
    Nature

    31 October 2017
    Ken Croswell

    Wonky orbit confirms that this visitor isn’t from around here.

    1
    The interstellar asteroid A/2017 U1 (circled) is rushing away from Earth and is currently traversing the Pisces constellation. Alan Fitzsimmons, Queen’s University Belfast/Isaac Newton Group, La Palma.

    Scientists are trying to learn everything that they can from the first interstellar asteroid they have ever observed crossing into our Solar System. Spotted less than two weeks ago, the object is now whizzing across the constellation Pisces and, in a couple of months, will be too faint and far away for even the largest telescopes to see.

    “It’s fascinating,” says astronomer David Jewitt of the University of California, Los Angeles. “We are seeing a body from elsewhere in the Galaxy passing through our Solar System. It’s the first time we’ve seen such a thing.”

    Unfortunately, the asteroid, dubbed A/2017 U1, is dashing away, never to return. “It’s going really fast,” says Jewitt. “So we have a limited time to get any measurements at all.” Astronomers would love to know what it’s made of, but it’s so dim that spectra — light that observers use to determine the compositions of celestial objects — have so far revealed little information1. Nor can anyone say what solar system it came from, or how old it is.

    A curious path

    Researchers with the Pan-STARRS1 telescope atop Haleakala in Maui, Hawaii, spied the first images of the intruder, made during the new Moon, in mid-October.

    Pann-STARS telescope, U Hawaii, Mauna Kea, Hawaii, USA, 4,207 m (13,802 ft) above sea level

    “It didn’t move like comets or asteroids normally do,” says astronomer Rob Weryk at the University of Hawaii at Manoa, who first noticed the object on the morning of 19 October.

    Comets and asteroids usually move on elliptical orbits around the Sun. These orbits have an eccentricity — a measure used to describe orbital shape — of less than 1. But an object zipping through the Solar System from beyond should instead follow a hyperbolic orbit, whose eccentricity exceeds 1.

    The latest observations of the asteroid’s changing position indicate that its orbital eccentricity is a whopping 1.20. “It is virtually certain that the object moves in a hyperbolic trajectory,” says Carlos de la Fuente Marcos, an astronomer at the Complutense University of Madrid.

    The asteroid skirted the Sun on 9 September, when it was inside Mercury’s orbit, and then passed by Earth at a distance of 24 million kilometres on 14 October.

    On the lookout

    Astronomers know little else about the exotic visitor. It’s faint, which means that it’s small: fewer than 400 metres across. And despite its excursion near the Sun, it did not develop a tail — as a comet would — and so astronomers are currently classifying it as an asteroid.

    2
    The path of A/2017 U1, an interstellar object that swung through our Solar System. NASA/JPL-Caltech

    Researchers have anticipated interstellar visitors for years. “We have waited a long time,” says planetary scientist Alan Stern at the Southwest Research Institute in Boulder, Colorado, who studied the matter in the 1990s.

    That expectation is based on the knowledge that the gravitational pulls of the giant planets Jupiter, Saturn, Uranus and Neptune catapulted trillions of comets and asteroids from the young Solar System into interstellar space. Planets in other solar systems presumably did the same, littering interstellar space with rogue objects. “By measuring how many there are sweeping through our Solar System, we can get a gauge of how many are in the entire Galaxy, and how many solar systems have contributed to that population,” says Stern.

    “If one hadn’t been discovered fairly soon, that would start to worry me a bit,” says astronomer David Hughes, emeritus professor at the University of Sheffield, UK.

    The asteroid came from the direction of the constellation Lyra, which is roughly where our Solar System is heading. Given this trajectory, researchers are expecting to see more objects coming from this direction than from elsewhere, just as runners heading into the rain encounter more drops on their chests than their backs.

    A/2017 U1 is the first of many such objects, predicts Jewitt.

    References

    Masiero, J. Preprint at http://arxiv.org/abs/1710.09977 (2017).

    See the full article here .

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  • richardmitnick 9:35 am on September 27, 2017 Permalink | Reply
    Tags: A new way to hunt for superconductors, , Discovering new states of matter, NATURE, Physicist Gil Lonzarich,   

    From Nature: “A quantum pioneer unlocks matter’s hidden secrets” 

    Nature Mag
    Nature

    27 September 2017
    Elizabeth Gibney

    1
    Physicist Gil Lonzarich has sparked a revolution in the study of phase transitions driven by quantum fluctuations.

    In 1989, surgery for detached retinas left Gilbert Lonzarich blind for a month. Rather than feel shaken or depressed, the condensed-matter physicist at the University of Cambridge, UK, seized the opportunity, inviting his graduate students to his house to share with them how exciting it was to adapt to life without sight. Lonzarich’s embrace of the experience perfectly captures his approach to life, says Andrew Mackenzie, then one of those students and now a director at the Max Planck Institute for Chemical Physics of Solids in Dresden, Germany. “Gil is one of the most positive people I’ve ever met. He finds interest in everything,” he says.

    For more than 40 years, that optimism and curiosity has led Lonzarich to probe materials in ways never thought possible. In pioneering experiments in the 1990s, his team showed that pushing magnetic compounds to extreme pressures and close to absolute zero can make some of them conduct electricity without resistance [1]. This flew in the face of convention, which declared that magnetism and superconductivity could never mix. “It was as if nowadays you were talking about finding aliens or something,” says Malte Grosche, a colleague at Cambridge.

    That work showed physicists a new way to hunt for superconductors, which lie at the heart of technologies such as magnetic resonance imagers and particle accelerators. In recent years, it has offered a potential explanation for why some materials remain superconductors at temperatures much higher than absolute zero, which could pave the way to developing efficient, cheap devices that superconduct at room temperature.

    But the experiments have had an impact well beyond superconductivity. Lonzarich’s method of subjecting materials to extreme conditions has become a general recipe for discovering new states of matter. Around the world, physicists now use this approach to probe a range of materials in which the collective interactions of electrons can give rise to unusual behaviour. Some of these phenomena could potentially revolutionize computing.

    Lonzarich’s research may be legendary in his community, but the physicist’s humility and generosity are what endear him to his colleagues. He is famously unconscious of time; a casual conversation with Lonzarich can easily lead to an hours-long random walk through the byways of physics, philosophy, politics and history. That might mean a missed lunch, says Michael Sutherland, a Cambridge colleague — “but it’s the most productive few hours you’ll have all week”. Phone calls with peers frequently last into the small hours of the morning, and on the rare occasions when Lonzarich goes to a conference, he invariably attracts a mass of fellow attendees. “People who meet him even once or twice develop a sense of attachment and awe,” says Louis Taillefer, another former student, who is now a physicist at the University of Sherbrooke in Canada.

    At 72, Lonzarich now has a part-time role in the Cambridge quantum-matter group, but he is still making new discoveries by pushing materials to ever-greater extremes. He sees this little-explored realm as just as fundamental to unravelling the laws of physics as the high-energy experiments at particle colliders, and expects that there is plenty more to discover. “Gil has never believed that we’re now just filling in the details,” says Piers Coleman, a theoretical physicist at Rutgers University in Piscataway, New Jersey. “He really views the exploration of quantum matter as a true frontier.”

    Collective efforts

    Walking around a timeworn study at Trinity College, Cambridge, Lonzarich is eager to point out a portrait of the economist John Kenneth Galbraith, one of his heroes, and he talks enthusiastically about the impressive work of his colleagues. But when conversation turns to his own achievements, Lonzarich becomes reticent. It is human nature is to celebrate heroes, he says, but science is a collective activity, and singling out individuals for praise stifles a team.

    Although colleagues are quick to highlight Lonzarich’s influence, he never would — a practice that could be traced back to his upbringing, by Italian parents, on the Istria peninsula. His father told him to “always cut the larger slice of the pie for the other person”, he recalls. At school, he learnt about the Roman Republic and was intrigued by the importance placed on reason, compromise and collaborative governance.

    His family moved to the United States when he was nine. By the 1960s, Lonzarich had grown into a studious young man. His interest in physics began at the University of California, Berkeley, where he earned a liberal arts degree. It was there that he met Gerie Simmons (now Lonzarich). The pair had admired each other from afar before she engineered their meeting by pretending to need a physics tutor; they married in 1967.

    “On the rare occasions I’ve seen pictures of him from those days, he had long hair. He was a physics hippy,” says Coleman. But although Lonzarich felt strongly that people should challenge the government, including the United States’ nascent war in Vietnam, he became disillusioned with the counter-culture’s free use of drugs and rejection of family. “I wanted to be able to do something tangible, to make good use of life. I didn’t think we were doing that,” he says.

    After a they spent a spell at the University of Minnesota in Minneapolis, the darker side of the movement eventually drove Gerie and Gil away from the United States altogether, to the University of British Columbia in Vancouver, Canada. There, Lonzarich became fascinated with magnetism, while working on his PhD in a new laboratory led by condensed-matter physicist Andrew Gold. When he left in 1976 for a stint at Cambridge, he found his new Rome. The collegiate structure had no real hierarchy and boasted two giants of condensed-matter physics — Brian Pippard and David Shoenberg. What was intended to be a one-year European adventure ended up lasting more than 40 years.

    Lonzarich arrived at Cambridge wanting to study magnets — materials in which the spins of electrons all spontaneously align. His approach raised a few eyebrows at first: he developed his own mathematical notation and would spend weeks preparing his experiments while seeming to do nothing. But his methods soon began to bear fruit.

    In magnetic materials, spins maintain their orderly arrangement only up to a point; above a certain temperature, electrons have so much energy that they can easily overcome the forces that cause their spins to align. Lonzarich reckoned that the best way to understand magnetic materials was to push them to that point, where they would be poised on the knife-edge between order and disorder. In particular, he was interested in exploring what might happen if the magnetic transition were shifted so that quantum effects could potentially alter the material’s state. At higher pressures, the transition occurs at lower temperatures. And with enough pressure, a material can be ‘tuned’ so that its magnetic transition point occurs close to absolute zero. Here, thermal vibrations don’t provide enough energy for the material to lose its magnetic order. Instead, quantum fluctuations — transient changes in electron properties, such as velocity and position, caused by the inherent uncertainty of the quantum world — dominate and can cause the material to switch states. In this regime, a region around a spot at absolute zero called the quantum critical point, magnetic materials become unstable and teeter on the brink of magnetism: they lack order but itch to align.

    With larger physical forces suppressed around the quantum critical point, ordinarily weak interactions between electrons could have huge effects. And they might, Lonzarich reasoned, give rise to new states of matter through their collective interaction. “It’s like in a forest; the little plants won’t grow until the big tree is cut down,” he says.

    In particular, Lonzarich predicted that antiferromagnets — magnetic materials in which neighbouring spins align in opposite directions below a certain temperature — would become superconducting near the quantum critical point. On the verge of magnetism, he reasoned, the electrons would be so eager to align that they might spontaneously form pairs with opposite spins. Such antiparallel pairs would stick together, and their attraction to each other would stabilize their journey through the material’s atomic lattice (see ‘Hidden powers‘).

    ______________________________________________________________________

    2
    ______________________________________________________________________

    Since the mid-1980s, various theorists had suggested that such magnetically mediated superconductivity could arise, but Lonzarich’s team was the first to provide solid experimental proof. When the group pushed a sample of the antiferromagnet cerium indium-3 close to the quantum critical point by cooling it at high pressure, the researchers saw it flip into a superconducting phase — something never before seen in a magnetic material1.

    The work, which was performed in 1994, demonstrated a new category of superconductor. It also provided a road map by which to search for other superconducting materials. Today, physicists routinely push the phase transition in magnetic materials down to absolute zero to see whether this behaviour emerges.

    New terrain

    The quantum critical point, and the strong quantum interactions that can take place around it, can give rise to other exotic states, not just superconductivity. “It’s like a breeding ground for discovering new states of matter,” says Cambridge physicist Stephen Rowley. Physicists around the world now manipulate a range of different factors — pressure, magnetic fields and chemical composition — to push phase transitions towards lower temperatures and so approach a quantum critical point.

    In the late 1990s, this method led Lonzarich and then-student Christian Pfleiderer to discover strange behaviour in the material manganese silicide [2]. Experiments done in the past few years have hinted that this may be connected to swirling two-dimensional magnetic vortices, known as skyrmions, that were later described by Pfleiderer and his colleagues [3] and are now being touted as a super-efficient way to store information. By probing around a quantum critical point of strontium ruthenate oxide, in 2007 Mackenzie and his team confirmed the existence of a new phase of matter, in which electrons flow but still show an orderly spatial structure [4].

    Fellow physicists say Lonzarich is unique in that he is not only a good theorist but also an exceptional experimenter. “You have to look back to Enrico Fermi to someone able to think so deeply about theory and do really good experiments,” says David Pines, a physicist and distinguished research professor at the University of California, Davis. Lonzarich grows his own samples to extreme levels of purity and pioneered a technique, known as quantum oscillation, that allows physicists to determine the electronic structure of complex, interacting systems [5]. Patricia Alireza, who runs the high-pressure laboratory at Cambridge’s Cavendish Laboratory, says that Lonzarich will often encourage her to create devices that squeeze samples well beyond what was thought possible. “Gil will smile and say, ‘I think we could probably do a factor of 100 better than that’,” she says. “And you know what? We always do.”

    Many of Lonzarich’s students have continued in physics and flourished. Suchitra Sebastian, for example, led work with Lonzarich a few years ago on samarium hexaboride, an insulator that exhibits metal-like behaviour when exposed to strong magnetic fields [6]. She says that without his advice she would probably have left the field. “He is not just teaching you ‘this is how you do physics’ but ‘this is how to survive in the world of physics’,” she says. Lonzarich is modest about how much he contributed to the success of those he has mentored, saying that they taught him at least as much as the other way around.

    One thing he always has for people is time, says Rowley. It helps that he is adept at escaping unnecessary bureaucracy, adds Pines. “He has many different offices so he can always hide at one.” But Lonzarich’s freedom to think is largely enabled by his wife, Gerie. She ensures that grant applications are handed in on time and that flights are caught. Gil says his wife is like the Sun: “So big and important that sometimes you forget it’s the reason everything is there.”

    Lingering mystery

    In the past few years, Lonzarich’s ideas about the intimate link between superconductivity and magnetism have gained new relevance. Physicists explain conventional superconductivity using BCS theory [7], named after the initials of the surnames of the three people who published it in 1957. The theory states that an electron speeding through some materials creates a positively charged distortion in the atomic lattice behind it. This pulls in a second electron, which follows the first like a cyclist riding in a competitor’s slipstream. If enough of these relatively stable ‘Cooper pairs’ form, they create an ordered state in which the two electrons keep one another on course and flow without resistance.

    But this explanation cannot account for sandwiches of copper-based insulators known as cuprates and for iron-based semiconductors. These two classes of superconductor can carry currents without resistance at temperatures up to 133 kelvin. If such transitions can be boosted to room temperature, around 300 kelvin, those superconductors could allow for cheaper energy, medical imaging and transportation. But debate about how they work has raged for 30 years.

    From the start, one camp thought that magnetic interaction — which can be more resilient to temperature than are interactions caused by distortions in the lattice — might somehow bind electrons together to create superconductivity in cuprates. Lonzarich theorized that this magnetic glue might stem from the same quantum fluctuations that ramp up around antiferromagnet quantum critical points. This idea is now hotly debated, and gained some supporting evidence last year in experiments conducted by Taillefer’s team, with collaborators at the National Laboratory for Intense Magnetic Fields in Toulouse, France. The group found that stripping a cuprate of its superconductivity with a powerful magnetic field and adding increasing levels of impurities revealed a sharp phase transition — an otherwise hidden quantum critical point [8]. Although the precise nature of that point is still not clear, it seems likely that antiferromagnetic correlations are at play, says Taillefer. “Which would mean Gil had a hell of an intuition,” he says.

    Lonzarich is now looking beyond conventional high-temperature superconductors. With Rowley and other colleagues, he is examining the nature of ferroelectrics, a little-studied class of ionic materials that generate their own electric field. At low temperature, ferroelectrics can become superconductors in a manner that parallels how superconductivity emerges in magnetic materials. Lonzarich has a hunch that in ferroelectric materials that also exhibit magnetism, electron pairs bind so strongly that the state could survive to room temperature.

    The Universe is richer than most scientists give it credit for, Lonzarich says. Each newly discovered state of matter emerges only when conditions are right and a material is sufficiently pure. Lonzarich speculates that probing the boundaries around those states could reveal more phases, and studying the boundaries of those could reveal yet more, with discoveries unfolding in a fractal manner. “What if each quantum critical point is just the beginning of another generation? There’s some indication we’re heading in that direction,” he says.

    The idea is highly speculative, but Taillefer says people would be wise to listen. The notion that a now-familiar principle could hide deep, complex behaviour “is typical Gil”, he says. “I would definitely put my money on him.”

    References:
    See the full article for references.

    See the full article here .

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  • richardmitnick 1:26 pm on August 26, 2017 Permalink | Reply
    Tags: , , , , , , NATURE, , Rumours swell over new kind of gravitational-wave sighting,   

    From Nature: “Rumours swell over new kind of gravitational-wave sighting” 

    Nature Mag
    Nature

    24 August 2017
    Davide Castelvecchi

    Gossip over potential detection of colliding neutron stars has astronomers in a tizzy.

    1
    The galaxy NGC 4993 (fuzzy bright spot) in the constellation Hydra, where detectors are rumoured to have spotted gravitational waves from a neutron star merger. Digitized Sky Survey

    Astrophysicists may have detected gravitational waves last week from the collision of two neutron stars in a distant galaxy — and telescopes trained on the same region might also have spotted the event.

    Rumours to that effect are spreading fast online, much to researchers’ excitement. Such a detection could mark a new era of astronomy: one in which phenomena are both seen by conventional telescopes and ‘heard’ as vibrations in the fabric of space-time. “It would be an incredible advance in our understanding,” says Stuart Shapiro, an astrophysicist at the University of Illinois at Urbana–Champaign.

    Scientists who work with gravitational-wave detectors won’t comment on the gossip because the data is still under analysis. Public records show that telescopes around the world have been looking at the same galaxy since last week, but astronomers caution that they could have been picking up signals from an unrelated source.

    As researchers hunt for signals in their data, Nature explains what is known so far, and the possible implications of any discovery.

    What is the gossip?

    The Laser Interferometer Gravitational-Wave Observatory (LIGO) in Louisiana and Washington state has three times detected gravitational waves — ripples in the fabric of space-time — emerging from colliding black holes.


    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project


    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    ESA/eLISA the future of gravitational wave research

    But scientists have been hoping to detect ripples from another cosmic cataclysm, such as the merger of neutron stars, remnants of large stars that exploded but were not massive enough to collapse into a black hole. Such an event should also emit radiation across the electromagnetic spectrum — from radio waves to γ-rays — which telescopes might be able to pick up.

    On 18 August, astronomer J. Craig Wheeler of the University of Texas at Austin began the public rumour mill when he tweeted, “New LIGO. Source with optical counterpart. Blow your sox off!” An hour later, astronomer Peter Yoachim of the University of Washington in Seattle tweeted that LIGO had seen a signal with an optical counterpart (that is, something that telescopes could see) from a galaxy called NGC 4993, which is around 40 million parsecs (130 million light years) away in the southern constellation Hydra. “Merging neutron-neutron star is the initial call”, he followed up. Some astronomers who do not want to be identified say that rumours had been privately circulating before Wheeler’s and Yoachim’s tweets.

    If gravitational-wave researchers saw a signal, it is plausible that they could know very quickly whether it emerged from colliding black holes or neutron stars, because each type of event has its own signature, even though data must be studied carefully to be more precise about an event’s origin.

    It’s also possible that LIGO’s sister observatory Virgo in Pisa, Italy, which has been helping LIGO to hunt for gravitational waves since August, after taking a break for an upgrade, might have spotted the event.

    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    That would give researchers more confidence about its source. (Virgo has an average sensitivity for neutron-star mergers of only 25 million to 27 million parsecs, but in some regions of the sky, it can see farther, up to 60 million parsecs away, says physicist Giovanni Losurdo, who led the detector’s upgrade work.)

    Both Wheeler and Yoachim declined to comment, and Wheeler later apologized on Twitter. “Right or wrong, I should not have sent that tweet. LIGO deserves to announce when they deem appropriate. Mea culpa,” he wrote.

    What about the telescope observations?

    Public records show that NASA’s Fermi Gamma-ray Space Telescope has spotted γ-rays emerging from the same region of sky as the potential gravitational-wave source.

    NASA/Fermi Telescope

    A senior Fermi member declined to comment on the observation, but it would be consistent with expectations that neutron-star collisions may be behind the enigmatic phenomena known as short γ-ray bursts (GRBs), which typically last a couple of seconds and are usually followed by an afterglow of visible light and sometimes, radio waves and x-rays, lasting up to a few days.

    But although the Fermi telescope has seen a GRB, it may not be able to pinpoint its origin with high precision, astronomers caution.

    2
    A simulation of the merger of a binary neutron star: magnetic field lines are in white. Simulations by M. Ruiz, R. N. Lang, V. Paschalidis and S. L.Shapiro at the University of Illinois at Urbana-Champaign, with visualization assistance from the Illinois Relativity REU team.

    Other telescopes were also turned to look at NGC 4993 after an alert about a potential gravitational wave sighting. On 22 August, a Twitter feed called Space Telescope Live, which provides live updates of what the Hubble Space Telescope is looking at, suggested that a team of astronomers was looking at a binary neutron-star merger using the probe’s on-board spectrograph, which is what astronomers would normally use to look at the afterglow of a short GRB. The Hubble tweet has since been deleted. Public records also confirm that multiple teams have used the Hubble Space Telescope over the last week to examine NGC 4993, and state as their reason that they are trying to follow up on a candidate observation of gravitational waves.

    On 23 August, a commenter on the blog of astrophysicist Peter Coles, of Cardiff University in the UK, noted that NASA’s Chandra X-ray observatory had jumped into the action, too.

    The Chandra website contains a public record of an observation made on 19 August.

    NASA/Chandra Telescope

    The telescope pointed at celestial coordinates in the galaxy NGC 4993 and observed an event called SGRB170817A — indicating ‘short GRB of 2017-August-17’. The most revealing part of the report is the “trigger criteria” section, which explains the reason for over-riding any previously scheduled observation to turn the telescope in that direction. It says: “Gravitational wave source detected by aLIGO, VIRGO, or both.”

    Publicly available records from other major astronomy facilities — including the European Southern Observatory’s Very Large Telescope and the world’s premiere radio observatory, the Atacama Large Millimeter/submillimeter Array (ALMA), both in Chile — show that those also targeted NGC 4993 on 18 and 19 August.

    ESO/VLT at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level

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

    What could we learn from a neutron-star merger?

    Gravitational-wave signals from black-hole mergers are brief, typically lasting a second or less. But a neutron-star merger could yield a signal that lasts up to a minute: neutron stars are less massive than black holes and emit less-powerful gravitational waves, so it takes longer for their orbits to decay and for the stars to spiral into each other. Longer events enable much more precise tests of Albert Einstein’s general theory of relativity, which predicts gravitational waves — perhaps giving more clues to the origins of neutron stars.

    The short GRB that telescopes might have observed would be significant, too — not least because if it is associated with gravitational waves, it would validate decades of astrophysical theorizing that GRBs are associated with neutron-star collisions. “Only gravitational waves could give us the smoking gun,” says Eleonora Troja, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

    Still, a short GRB would be an important discovery on its own. Most such events are seen in the distant Universe, billions of parsecs away. NGC 4993, at 40 million parsecs away, would probably be the closest short GRB ever detected, says astrophysicist Derek Fox of Pennsylvania State University in University Park.

    Details of the gravitational waves at the time of the collision and in the following instances could also reveal information about the structure of neutron stars — which is largely unknown — and whether their merger resulted again in a neutron star or in the formation of a new black hole.

    When will we know?

    On 25 August, LIGO and Virgo will end their current data-collecting run. After that, researchers will post only a “top-level update”, meaning a brief note indicating whether the observatories have picked up potential ‘candidate events’ that need further analysis, says David Shoemaker, a physicist at the Massachusetts Institute of Technology who is LIGO’s spokesperson.

    “It will take time to do justice to the data, and ensure that we publish things in which we have very high confidence,” he says.

    Update 25 August: The LIGO–Virgo collaboration posted its top-level update, saying: “Some promising gravitational-wave candidates have been identified in data from both LIGO and Virgo during our preliminary analysis, and we have shared what we currently know with astronomical observing partners. We are working hard to assure that the candidates are valid gravitational-wave events, and it will require time to establish the level of confidence needed to bring any results to the scientific community and the greater public. We will let you know as soon we have information ready to share.”

    See the full article here .

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    • Jose 5:40 am on October 29, 2017 Permalink | Reply

      The detection of the gravitational waves produced by the merger of two neutron stars –GW170817– has allowed scientists to fix at 70 km/s per megaparsec * the value of the increase in speed of the expansion of the universe in the 130 million light years that separate us from the origin of said merger.
      As these calculations approach the speed of light throughout the age of the universe, we can do the inverse calculation to determine the average increase in the velocity of expansion so that the observable universe is of the age stated by the Big Bang Theory.
      The result is 300.000 km/s /(13.799/3,26) Mpc =70,820 km/s Mpc. https://molwick.com/en/gravitation/072-gravitational-waves.html#big-bang

      Like

    • richardmitnick 7:09 am on October 29, 2017 Permalink | Reply

      Thanks for visiting sciencesprings. I went to your site. Beautiful and instructive.

      Like

    • Jose 12:34 pm on October 29, 2017 Permalink | Reply

      Thank you too. My pleasure!

      Like

  • richardmitnick 5:36 pm on July 11, 2017 Permalink | Reply
    Tags: , , Female astronomers of colour face daunting discrimination, NATURE, Not in this article but so do caucasion women esp in Physics and Astronomy   

    From Nature: “Female astronomers of colour face daunting discrimination” 

    Nature Mag
    Nature

    11 July 2017
    Rachael Lallensack

    Two-fifths report feeling unsafe at work, and 21% have concerns about attending conferences.

    Women of colour working in astronomy and planetary science experience high rates of harassment at work, a study finds. In a survey, a striking 40% of these scientists reported feeling unsafe in their workplaces owing to their gender, and 28% reported feeling unsafe on account of their race.

    The findings, published on 10 July in the Journal of Geophysical Research: Planets [1], illustrate a well-researched phenomenon: a woman’s risk of being subjected to gendered or race-based harassment is higher if she belongs to multiple minority groups. Women of colour were more likely than white women or men of colour to recall a negative workplace experience during a five-year period from 2011-2015. Such incidents included having their mental or physical ability questioned.

    “This is something that I’ve known about, that I’ve seen and experienced, as someone of colour, for as long as I’ve been in the field. So I’m not surprised,” says Cristina Thomas, an astronomer at the Planetary Science Institute who is based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “I was very happy to see someone quantify what was happening so other people would see it.”

    The study, whose participants ranged from undergraduate students to senior researchers, suggests that the negative environment experienced by many female scientists of colour is often apparent to colleagues of other genders or ethnicities.

    Eighty-eight per cent of the 474 participants — a group that was 84% white and included both men and women — had heard remarks that were racist, sexist or directed at a person’s gender or intelligence in their current workplace.

    Survey respondents included 45 women of colour, who collectively accounted for 11% of participants. That proportion is double the percentage of minority women in the United States who hold bachelor’s degrees in physical science. [That is a sad statistic. In The U.S. we suck at acknowledging talent and we just lose it.]

    The analysis is the first of its kind in the astronomy and planetary-science fields, and one of few in a science, technology, engineering or medicine discipline that specifically examines the experiences of women of colour, says study co-author Christina Richey, former chair of the American Astronomical Society’s Committee on the Status of Women in Astronomy in Washington DC. The research team was made up of two planetary scientists and two social scientists, including anthropologist Kathryn Clancy of the University of Illinois at Urbana-Champaign, who led a high-profile survey of harassment in scientific fieldwork that was published in 2014 in PLoS ONE [2]

    The latest study found that harassment and discrimination can have a heavy impact on an individual’s career decisions. Twenty-one per cent of men of colour, 18% of women of colour and 12% of white women reported avoiding a class, conference or professional event because they did not feel safe attending. [Think of the talent lost.] Such events can help to foster professional networks, mentorship and opportunities for collaboration — connections that can advance a scientist’s career, says Zuleyka Zevallos, a sociologist at Swinburne University of Technology in Melbourne, Australia.

    Systemic solutions

    “If a culture of hostility remains in place, it doesn’t matter what we do at the individual level because the system is broken. The pipeline is broken,” says Zevallos, who helped to implement gender-education programmes at universities in her former position at the Australian Academy of Science in Canberra.

    The analysis has sparked intense discussion online among astronomers and planetary scientists. Several female scientists of colour have shared their stories on Twitter, describing the significant, but sometimes subtle, consequences of harassment and discrimination in their own lives.

    Chanda Prescod-Weinstein, a theoretical physicist at the University of Washington in Seattle, tweeted that when faced with events that she thought might expose her to harassment, discrimination or other negative experiences, she sometimes brought her husband along. But that created an extra financial burden for the couple.

    In recent years, professional societies such as the American Astronomical Society and American Geophysical Union have taken steps to prevent harassment at their meetings. The latest study suggests several actions that research institutions, funding agencies and scientific societies can take to reduce harassment. These include updating their codes of conduct to bar harassment; instituting mandatory cultural-awareness training; encouraging leading researchers to model appropriate behaviour; and putting in place swift sanctions for perpetrators.

    “It’s time to pivot away from the conversation of, ‘Is gender equity and racism a problem in science?’, and shift to taking action,” Zevallos says. “We can’t afford to lose more women of colour, white women and under-represented minorities.”

    [Think about it: if a back Jewish female lesbian magician pulled a rabbit out of a hat, no one would give a rat’s ass about her race, religion or sexual preference. She just pulled a rabbit out of a hat.]

    See the full article here .

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 10:12 am on July 5, 2017 Permalink | Reply
    Tags: , “...Full and continued engagement” with the United Kingdom in FP9 would be “an obvious win-win for the UK and the EU”, , , Europe’s next big science-funding programme urged to double its budget, FP9-Framework Programme Nine, , Less bureaucracy, NATURE, One-fifth of the number of fast-growing start-up firms that the United States does, Pascal Lamy, Science Europe, The region trails South Korea on business-research spending, Uncertainty over Brexit negotiations   

    From Nature: “Europe’s next big science-funding programme urged to double its budget” 

    Nature Mag
    Nature

    04 July 2017
    Alison Abbott

    1
    Pascal Lamy. Julien Warnand/EPA.

    Midway through the European Union’s sprawling 7-year, €75-billion (US$85-billion) research-funding programme known as Horizon 2020 (H2020), scientists are already angling for more money and less red tape in its successor.

    So researchers are delighted with an influential 3 July report that urges the EU to double the budget of its next funding scheme, called Framework Programme Nine (FP9), which is due to launch in 2021. The report says that FP9’s structure should be largely similar to that of H2020, but with less bureaucracy, and suggests that it includes a few major ‘moonshot’ missions in areas such as energy and information technology.

    “Scientists are generally happy with the report because it mostly confirms our thinking,” says Stephan Kuster, the acting director of Science Europe, a Brussels-based organization that represents member-state research agencies. But it lacks details on some of its aims, he says: in particular, how to persuade politicians to approve such a large budget hike.

    The report comes from a group of academic and industry experts invited by the European Commission to formulate a vision for future research plans, headed by a former director-general of the World Trade Organization, Pascal Lamy. Commission insiders say its ideas will strongly influence the shape of FP9 — set to be the first major EU funding programme to take place after the United Kingdom leaves the union in 2019.

    Uncertainty over Brexit negotiations means that the commission isn’t close to determining its total post-2020 budget, and it will not propose what FP9 might look like until the end of this year. That has not stopped advocates asking for more cash: in June, a research committee for the European Parliament proposed a €120-billion budget for FP9, assuming that, like H2020, it will run for 7 years.

    In an interview with the European Commission alongside his report, Lamy calls that “a bare minimum”. His team’s report says that whatever the result of Brexit negotiations, “full and continued engagement” with the United Kingdom in FP9 would be “an obvious win-win for the UK and the EU”. The programme should also be opened up more widely to non-EU countries, the report says.

    Falling success rates

    European scientists have a love–hate relationship with the EU’s massive research programmes. Researchers appreciate the funding and the support of collaborative projects, but deplore the bureaucracy and the way each new programme changes the rules. An interim evaluation of H2020, published in May, suggests it has been more popular than its predecessors, in part because of cuts to red tape.

    Still, the evaluation noted that H2020 is heavily oversubscribed, with barely 1 in 9 applications funded — well down on its predecessor programme, which funded nearly 1 in 5. FP9 should return to earlier levels, the Lamy report says.

    Success rates are even lower, below 1 in 10, at the prestigious European Research Council (ERC), which as part of H2020 was given a €13.1-billion budget to fund basic research for 2014–20. The ERC is supposed to reward excellence, but in some of its grant programmes, half of the projects deemed “excellent” by reviewers have gone unfunded. “We would need to double our budget to make sense of our mission,” says ERC president Jean-Pierre Bourguignon.

    The Lamy report recommends keeping H2020’s broad divisions into grants for excellent science, for industrial-innovation projects, and for multinational collaborations that meet societal grand challenges. It suggests that rules of participation be made simpler — with documentation and reporting obligations kept to a minimum, and audits restricted to cases where fraud is suspected. And it proposes that FP9 adopt broader measures of the ‘impact’ of work — going beyond scientific impact to capture effects on policymaking and industrial competitiveness, for instance.

    The EU has an ‘innovation gap’ compared with its trading partners, the report says, noting that the region trails South Korea on business-research spending, and has one-fifth of the number of fast-growing start-up firms that the United States does.

    The report also argues that FP9 should do more to involve Europe’s citizens, including involving them in choosing ‘moonshot’ missions in areas of societal importance, such as climate change, that set targets to be achieved within precise time frames. (As an example, it suggests producing carbon-free steel by 2030.)

    In general, scientists should get better at communicating their work using stories that citizens can understand, the report says: “Communicating on science should become part of researchers’ career and their reward system.”

    See the full article here .

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 1:15 pm on June 25, 2017 Permalink | Reply
    Tags: , , Bacteriophages, , Genetically modified viruses, NATURE   

    From Nature: “Modified viruses deliver death to antibiotic-resistant bacteria” 

    Nature Mag
    Nature

    21 June 2017
    Sara Reardon

    Engineered microbes turn a bacterium’s immune response against itself using CRISPR.

    1
    Phages (green) attack a bacterium (orange). Researchers are hoping to use engineered versions of these viruses to fight antibiotic resistance. AMI Images/SPL

    Genetically modified viruses that cause bacteria to kill themselves could be the next step in combating antibiotic-resistant infections [Nature].

    Several companies have engineered such viruses, called bacteriophages, to use the CRISPR gene-editing system to kill specific bacteria, according to a presentation at the CRISPR 2017 conference in Big Sky, Montana, last week. These companies could begin clinical trials of therapies as soon as next year.

    Initial tests have saved mice from antibiotic-resistant infections that would otherwise have killed them, said Rodolphe Barrangou, chief scientific officer of Locus Biosciences in Research Triangle Park, North Carolina, at the conference.

    Bacteriophages isolated and purified from the wild have long been used to treat infections in people, particularly in Eastern Europe. These viruses infect only specific species or strains of bacteria, so they have less of an impact on the human body’s natural microbial community, or microbiome, than antibiotics do. They are also generally thought to be very safe for use in people.

    But the development of phage therapy has been slow, in part because these viruses are naturally occurring and so cannot be patented. Bacteria can also quickly evolve resistance to natural phages, meaning researchers would have to constantly isolate new ones capable of defeating the same bacterial strain or species. And it would be difficult for regulatory agencies to continually approve each new treatment.

    CRISPR-fuelled death

    To avoid these issues, Locus and several other companies are developing phages that turn the bacterial immune system known as CRISPR against itself. In Locus’ phages, which target bacteria resistant to antibiotics, the CRISPR system includes DNA with instructions for modified guide RNAs that home in on part of an antibiotic-resistance gene. Once the phage infects a bacterium, the guide RNA latches on to the resistance gene. That prompts an enzyme called Cas3, which the bacterium normally produces to kill phages, to destroy that genetic sequence instead. Cas3 eventually destroys all the DNA, killing the bacterium. “I see some irony now in using phages to kill bacteria,” says Barrangou.

    Another company, Eligo Bioscience in Paris, uses a similar approach. It has removed all the genetic instructions that allow phages to replicate, and inserted DNA that encodes guide RNAs and the bacterial enzyme Cas9. Cas9 cuts the bacterium’s DNA at a designated spot, and the break triggers the bacterium to self-destruct. The system will target human gut pathogens, says Eligo chief executive Xavier Duportet, although he declined to specify which ones.

    The two companies hope to start clinical trials in 18–24 months. Their first goal is to treat bacterial infections that cause severe disease. But eventually, they want to develop phages that let them precisely engineer the human microbiome by removing naturally occurring bacteria associated with conditions such as obesity, autism and some cancers.

    Both Barrangou and Duportet acknowledge that for now, causal links between the human microbiome and these conditions are tenuous at best. But they hope that by the time their therapies have been proved safe and effective in humans, the links will be better understood. Phages could also allow researchers to manipulate the microbiomes of experimental animals, which could help them to untangle how certain bacteria influence conditions such as autism, says Timothy Lu, a synthetic biologist at the Massachusetts Institute of Technology in Cambridge and a co-founder of Eligo.

    An engineered solution

    Other companies are working to get phages to perform different tasks. ‘Supercharged’ phages, created by a group at Synthetic Genomics in La Jolla, California, could contain dozens of special features, including enzymes that break down biofilms or proteins that help to hide the phages from the human immune system.

    But engineered phages still have to overcome some hurdles. Treating an infection might require a large volume of phages, says Elizabeth Kutter, a microbiologist at Evergreen State College in Olympia, Washington, and it’s unclear whether this would trigger immune reactions, some of which could interfere with the treatment. Phages could also potentially transfer antibiotic-resistance genes to non-resistant bacteria, she notes.

    Lu adds that bacteria may still develop resistance even to the engineered phages. So researchers might have to frequently modify their phages to keep up with bacterial mutations.

    But as antibiotic resistance spreads, Kutter says, there will be plenty of space for both engineered phages and natural phage therapies, which are also growing in popularity. “I think they’ll complement the things that can be done by natural phages that have been engineered for hundreds of thousands of years,” she says.

    Related stories and links
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    See the full article here .

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
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