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News Article | December 12, 2016
Site: www.eurekalert.org

In 2015, the All Sky Automated Survey for SuperNovae (ASAS-SN) detected an event, named ASASSN-15lh, that was recorded as the brightest supernova ever -- and categorised as a superluminous supernova, the explosion of an extremely massive star at the end of its life. It was twice as bright as the previous record holder, and at its peak was 20 times brighter than the total light output of the entire Milky Way. An international team, led by Giorgos Leloudas at the Weizmann Institute of Science, Israel, and the Dark Cosmology Centre, Denmark, has now made additional observations of the distant galaxy, about 4 billion light-years from Earth, where the explosion took place and they have proposed a new explanation for this extraordinary event. "We observed the source for 10 months following the event and have concluded that the explanation is unlikely to lie with an extraordinarily bright supernova. Our results indicate that the event was probably caused by a rapidly spinning supermassive black hole as it destroyed a low-mass star," explains Leloudas. In this scenario, the extreme gravitational forces of a supermassive black hole, located in the centre of the host galaxy, ripped apart a Sun-like star that wandered too close -- a so-called tidal disruption event, something so far only observed about 10 times. In the process, the star was "spaghettified" and shocks in the colliding debris as well as heat generated in accretion led to a burst of light. This gave the event the appearance of a very bright supernova explosion, even though the star would not have become a supernova on its own as it did not have enough mass. The team based their new conclusions on observations from a selection of telescopes, both on the ground and in space. Among them was the Very Large Telescope at ESO's Paranal Observatory, the New Technology Telescope at ESO's La Silla Observatory and the NASA/ESA Hubble Space Telescope [1]. The observations with the NTT were made as part of the Public ESO Spectroscopic Survey of Transient Objects (PESSTO). "There are several independent aspects to the observations that suggest that this event was indeed a tidal disruption and not a superluminous supernova," explains coauthor Morgan Fraser from the University of Cambridge, UK (now at University College Dublin, Ireland). In particular, the data revealed that the event went through three distinct phases over the 10 months of follow-up observations. These data overall more closely resemble what is expected for a tidal disruption than a superluminous supernova. An observed re-brightening in ultraviolet light as well as a temperature increase further reduce the likelihood of a supernova event. Furthermore, the location of the event -- a red, massive and passive galaxy -- is not the usual home for a superluminous supernova explosion, which normally occur in blue, star-forming dwarf galaxies. Although the team say a supernova source is therefore very unlikely, they accept that a classical tidal disruption event would not be an adequate explanation for the event either. Team member Nicholas Stone from Columbia University, USA, elaborates: "The tidal disruption event we propose cannot be explained with a non-spinning supermassive black hole. We argue that ASASSN-15lh was a tidal disruption event arising from a very particular kind of black hole." The mass of the host galaxy implies that the supermassive black hole at its centre has a mass of at least 100 million times that of the Sun. A black hole of this mass would normally be unable to disrupt stars outside of its event horizon -- the boundary within which nothing is able to escape its gravitational pull. However, if the black hole is a particular kind that happens to be rapidly spinning -- a so-called Kerr black hole -- the situation changes and this limit no longer applies. "Even with all the collected data we cannot say with 100% certainty that the ASASSN-15lh event was a tidal disruption event," concludes Leloudas. "But it is by far the most likely explanation." [1] As well as the data from ESO's Very Large Telescope, the New Technology Telescope and the NASA/ESA Hubble Space Telescope the team used observations from NASA's Swift telescope, the Las Cumbres Observatory Global Telescope (LCOGT), the Australia Telescope Compact Array, ESA's XMM-Newton, the Wide-Field Spectrograph (WiFeS and the Magellan Telescope. This research was presented in a paper entitled "The Superluminous Transient ASASSN-15lh as a Tidal Disruption Event from a Kerr Black Hole", by G. Leloudas et al. to appear in the new Nature Astronomy magazine. The team is composed of G. Leloudas (Weizmann Institute of Science, Rehovot, Israel; Niels Bohr Institute, Copenhagen, Denmark), M. Fraser (University of Cambridge, Cambridge, UK), N. C. Stone (Columbia University, New York, USA), S. van Velzen (The Johns Hopkins University, Baltimore, USA), P. G. Jonker (Netherlands Institute for Space Research, Utrecht, the Netherlands; Radboud University Nijmegen, Nijmegen, the Netherlands), I. Arcavi (Las Cumbres Observatory Global Telescope Network, Goleta, USA; University of California, Santa Barbara, USA), C. Fremling (Stockholm University, Stockholm, Sweden), J. R. Maund (University of Sheffield, Sheffield, UK), S. J. Smartt (Queen's University Belfast, Belfast, UK), T. Krühler (Max-Planck-Institut für extraterrestrische Physik, Garching b. München, Germany), J. C. A. Miller-Jones (ICRAR - Curtin University, Perth, Australia), P. M. Vreeswijk (Weizmann Institute of Science, Rehovot, Israel), A. Gal-Yam (Weizmann Institute of Science, Rehovot, Israel), P. A. Mazzali (Liverpool John Moores University, Liverpool, UK; Max-Planck-Institut für Astrophysik, Garching b. München, Germany), A. De Cia (European Southern Observatory, Garching b. München, Germany), D. A. Howell (Las Cumbres Observatory Global Telescope Network, Goleta, USA; University of California Santa Barbara, Santa Barbara, USA), C. Inserra (Queen's University Belfast, Belfast, UK), F. Patat (European Southern Observatory, Garching b. München, Germany), A. de Ugarte Postigo (Instituto de Astrofisica de Andalucia, Granada, Spain; Niels Bohr Institute, Copenhagen, Denmark), O. Yaron (Weizmann Institute of Science, Rehovot, Israel), C. Ashall (Liverpool John Moores University, Liverpool, UK), I. Bar (Weizmann Institute of Science, Rehovot, Israel), H. Campbell (University of Cambridge, Cambridge, UK; University of Surrey, Guildford, UK), T.-W. Chen (Max-Planck-Institut für extraterrestrische Physik, Garching b. München, Germany), M. Childress (University of Southampton, Southampton, UK), N. Elias-Rosa (Osservatoria Astronomico di Padova, Padova, Italy), J. Harmanen (University of Turku, Piikkiö, Finland), G. Hosseinzadeh (Las Cumbres Observatory Global Telescope Network, Goleta, USA; University of California Santa Barbara, Santa Barbara, USA), J. Johansson (Weizmann Institute of Science, Rehovot, Israel), T. Kangas (University of Turku, Piikkiö, Finland), E. Kankare (Queen's University Belfast, Belfast, UK), S. Kim (Pontificia Universidad Católica de Chile, Santiago, Chile), H. Kuncarayakti (Millennium Institute of Astrophysics, Santiago, Chile; Universidad de Chile, Santiago, Chile), J. Lyman (University of Warwick, Coventry, UK), M. R. Magee (Queen's University Belfast, Belfast, UK), K. Maguire (Queen's University Belfast, Belfast, UK), D. Malesani (University of Copenhagen, Copenhagen, Denmark; DTU Space, Denmark), S. Mattila (University of Turku, Piikkiö, Finland; Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Piikkiö, Finland; University of Cambridge, Cambridge, UK), C. V. McCully (Las Cumbres Observatory Global Telescope Network, Goleta, USA; University of California Santa Barbara, Santa Barbara, USA), M. Nicholl (Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA), S. Prentice (Liverpool John Moores University, Liverpool, UK), C. Romero-Ca[ñ] - https:/ izales (Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Astrophysics, Santiago, Chile), S. Schulze (Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Astrophysics, Santiago, Chile), K. W. Smith (Queen's University Belfast, Belfast, UK), J. Sollerman (Stockholm University, Stockholm, Sweden), M. Sullivan (University of Southampton, Southampton, UK), B. E. Tucker (Australian National University, Canberra, Australia; ARC Centre of Excellence for All-sky Astrophysics (CAASTRO), Australia), S. Valenti (University of California, Davis, USA), J. C. Wheeler (University of Texas at Austin, Austin, USA), and D. R. Young (Queen's University Belfast, Belfast, UK). ESO is the foremost intergovernmental astronomy organisation in Europe and the world's most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world's largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become "the world's biggest eye on the sky".


News Article | November 17, 2016
Site: phys.org

Though astronomers still do not know what kinds of events or objects produce FRBs, the discovery is a stepping stone for astronomers to understand the diffuse, faint web of material that exists between galaxies, called the cosmic web. The findings are described in a paper appearing in Science on November 17. "Because FRBs like the one we discovered occur billions of light-years away, they help us study the universe between us and them," says Ravi, who is the R A and G B Millikan Postdoctoral Scholar in Astronomy. "Nearly half of all visible matter is thought to be thinly spread throughout intergalactic space. Although this matter is not normally visible to telescopes, it can be studied using FRBs." When FRBs travel through space, they pass through intergalactic material and are distorted, similar to the apparent twinkling of a star because its light is distorted by Earth's atmosphere. By observing these bursts, astronomers can learn details about the regions of the universe through which the bursts traveled on their way to Earth. FRB 150807 appears to only be weakly distorted by material within its host galaxy, which shows that the intergalactic medium in this direction is no more turbulent than theorists originally predicted. This is the first direct insight into turbulence in intergalactic medium. The researchers observed FRB 150807 while monitoring a nearby pulsar—a rotating neutron star that emits a beam of radio waves and other electromagnetic radiation—in our galaxy using the Parkes radio telescope in Australia. "Thanks to a real-time detection system developed by the Swinburne University of Technology, we found that although the FRB is a million times further away than the pulsar, the magnetic fields in their directions appear identical," says Ryan Shannon, research fellow at Commonwealth Scientific and Industrial Research Organisation (CSIRO) Astronomy and Space Science and at Curtin University in Australia, and colead author of the study. This refutes some claims that FRBs are produced in dense environments with strong magnetic fields. The result provides a measure of the magnetism in the space between galaxies, an essential step in determining how cosmic magnetic fields are produced. Only 18 FRBs have been detected to date. Mysteriously, most give off only a single burst and do not flash repeatedly. Additionally, most FRBs have been detected with telescopes that observe large swaths of the sky but with poor resolution, making it difficult to pinpoint the exact location of a given burst. The unprecedented brightness of FRB 150807 allowed Ravi and his team to localize it much more accurately, making it the best-localized FRB to date. In February 2017, pinpointing the locations of FRBs will become much easier for astronomers with the commissioning of the Deep Synoptic Array prototype, an array of 10 radio dishes at Caltech's Owens Valley Radio Observatory in California. "We estimate that there are between 2,000 and 10,000 FRBs occurring in the sky every day," Ravi says. "One in 10 of these are as bright as FRB 150807, and the Deep Synoptic Array prototype will be able to pinpoint their locations to individual galaxies. Measuring the distances to these galaxies enables us to use FRBs to weigh the tenuous intergalactic material." Ravi is the project scientist for the Deep Synoptic Array prototype, which is being constructed by the Jet Propulsion Laboratory (JPL) and Caltech and funded by the National Aeronautics and Space Administration through the JPL President's and Director's Fund Program. The paper is titled "The magnetic field and turbulence of the cosmic web measured using a brilliant fast radio burst." More information: "The magnetic field and turbulence of the cosmic web measured using a brilliant fast radio burst," Science, science.sciencemag.org/lookup/doi/10.1126/science.aaf6807


News Article | November 17, 2016
Site: www.sciencedaily.com

Fast radio bursts, or FRBs, are mysterious flashes of radio waves originating outside our Milky Way galaxy. A team of scientists, jointly led by Caltech postdoctoral scholar Vikram Ravi and Curtin University research fellow Ryan Shannon, has now observed the most luminous FRB to date, called FRB 150807. Though astronomers still do not know what kinds of events or objects produce FRBs, the discovery is a stepping stone for astronomers to understand the diffuse, faint web of material that exists between galaxies, called the cosmic web. The findings are described in a paper appearing in Science on November 17. "Because FRBs like the one we discovered occur billions of light-years away, they help us study the universe between us and them," says Ravi, who is the R A and G B Millikan Postdoctoral Scholar in Astronomy. "Nearly half of all visible matter is thought to be thinly spread throughout intergalactic space. Although this matter is not normally visible to telescopes, it can be studied using FRBs." When FRBs travel through space, they pass through intergalactic material and are distorted, similar to the apparent twinkling of a star because its light is distorted by Earth's atmosphere. By observing these bursts, astronomers can learn details about the regions of the universe through which the bursts traveled on their way to Earth. FRB 150807 appears to only be weakly distorted by material within its host galaxy, which shows that the intergalactic medium in this direction is no more turbulent than theorists originally predicted. This is the first direct insight into turbulence in intergalactic medium. The researchers observed FRB 150807 while monitoring a nearby pulsar -- a rotating neutron star that emits a beam of radio waves and other electromagnetic radiation -- in our galaxy using the Parkes radio telescope in Australia. "Thanks to a real-time detection system developed by the Swinburne University of Technology, we found that although the FRB is a million times further away than the pulsar, the magnetic fields in their directions appear identical," says Ryan Shannon, research fellow at Commonwealth Scientific and Industrial Research Organisation (CSIRO) Astronomy and Space Science and at Curtin University in Australia, and colead author of the study. This refutes some claims that FRBs are produced in dense environments with strong magnetic fields. The result provides a measure of the magnetism in the space between galaxies, an essential step in determining how cosmic magnetic fields are produced. Only 18 FRBs have been detected to date. Mysteriously, most give off only a single burst and do not flash repeatedly. Additionally, most FRBs have been detected with telescopes that observe large swaths of the sky but with poor resolution, making it difficult to pinpoint the exact location of a given burst. The unprecedented brightness of FRB 150807 allowed Ravi and his team to localize it much more accurately, making it the best-localized FRB to date. In February 2017, pinpointing the locations of FRBs will become much easier for astronomers with the commissioning of the Deep Synoptic Array prototype, an array of 10 radio dishes at Caltech's Owens Valley Radio Observatory in California. "We estimate that there are between 2,000 and 10,000 FRBs occurring in the sky every day," Ravi says. "One in 10 of these are as bright as FRB 150807, and the Deep Synoptic Array prototype will be able to pinpoint their locations to individual galaxies. Measuring the distances to these galaxies enables us to use FRBs to weigh the tenuous intergalactic material." Ravi is the project scientist for the Deep Synoptic Array prototype, which is being constructed by the Jet Propulsion Laboratory (JPL) and Caltech and funded by the National Aeronautics and Space Administration through the JPL President's and Director's Fund Program.


News Article | February 27, 2017
Site: www.eurekalert.org

Today's Earth is a dynamic planet with an outer layer composed of giant plates that grind together, sliding past or dipping beneath one another, giving rise to earthquakes and volcanoes. Others separate at undersea mountain ridges, where molten rock spreads out from the centers of major ocean basins. But new research suggests that this was not always the case. Instead, shortly after Earth formed and began to cool, the planet's first outer layer was a single, solid but deformable shell. Later, this shell began to fold and crack more widely, giving rise to modern plate tectonics. The research, described in a paper published February 27, 2017 in the journal Nature, is the latest salvo in a long-standing debate in the geological research community: did plate tectonics start right away--a theory known as uniformitarianism--or did Earth first go through a long phase with a solid shell covering the entire planet? The new results suggest the solid shell model is closest to what really happened. "Models for how the first continental crust formed generally fall into two groups: those that invoke modern-style plate tectonics and those that do not," said Michael Brown, a professor of geology at the University of Maryland and a co-author of the study. "Our research supports the latter--a 'stagnant lid' forming the planet's outer shell early in Earth's history." To reach these conclusions, Brown and his colleagues from Curtin University and the Geological Survey of Western Australia studied rocks collected from the East Pilbara Terrane, a large area of ancient granitic crust located in the state of Western Australia. Rocks here are among the oldest known, ranging from 3.5 to about 2.5 billion years of age. (Earth is roughly 4.5 billion years old.) The researchers specifically selected granites with a chemical composition usually associated with volcanic arcs--a telltale sign of plate tectonic activity. Brown and his colleagues also looked at basalt rocks from the associated Coucal formation. Basalt is the rock produced when volcanoes erupt, but it also forms the ocean floor, as molten basalt erupts at spreading ridges in the center of ocean basins. In modern-day plate tectonics, when ocean floor basalt reaches the continents, it dips--or subducts--beneath the Earth's surface, where it generates fluids that allow the overlying mantle to melt and eventually create large masses of granite beneath the surface. Previous research suggested that the Coucal basalts could be the source rocks for the granites in the Pilbara Terrane, because of the similarities in their chemical composition. Brown and his collaborators set out to verify this, but also to test another long-held assumption: could the Coucal basalts have melted to form granite in some way other than subduction of the basalt beneath Earth's surface? If so, perhaps plate tectonics was not yet happening when the Pilbara granites formed. To address this question, the researchers performed thermodynamic calculations to determine the phase equilibria of average Coucal basalt. Phase equilibria are precise descriptions of how a substance behaves under various temperature and pressure conditions, including the temperature at which melting begins, the amount of melt produced and its chemical composition. For example, one of the simplest phase equilibria diagrams describes the behavior of water: at low temperatures and/or high pressures, water forms solid ice, while at high temperatures and/or low pressures, water forms gaseous steam. Phase equilibria gets a bit more involved with rocks, which have complex chemical compositions that can take on very different mineral combinations and physical characteristics based on temperature and pressure. "If you take a rock off the shelf and melt it, you can get a phase diagram. But you're stuck with a fixed chemical composition," Brown said. "With thermodynamic modeling, you can change the composition, pressure and temperature independently. It's much more flexible and helps us to answer some questions we can't address with experiments on rocks." Using the Coucal basalts and Pilbara granites as a starting point, Brown and his colleagues constructed a series of modeling experiments to reflect what might have transpired in an ancient Earth without plate tectonics. Their results suggest that, indeed, the Pilbara granites could have formed from the Coucal basalts. More to the point, this transformation could have occurred in a pressure and temperature scenario consistent with a "stagnant lid," or a single shell covering the entire planet. Plate tectonics substantially affects the temperature and pressure of rocks within Earth's interior. When a slab of rock subducts under the Earth's surface, the rock starts off relatively cool and takes time to gain heat. By the time it reaches a higher temperature, the rock has also reached a significant depth, which corresponds to high pressure--in the same way a diver experiences higher pressure at greater water depth. In contrast, a "stagnant lid" regime would be very hot at relatively shallow depths and low pressures. Geologists refer to this as a "high thermal gradient." "Our results suggest the Pilbara granites were produced by melting of the Coucal basalts or similar materials in a high thermal gradient environment," Brown said. "Additionally, the composition of the Coucal basalts indicates that they, too, came from an earlier generation of source rocks. We conclude that a multi-stage process produced Earth's first continents in a 'stagnant lid' scenario before plate tectonics began." The research paper, "Earth's first stable continents did not form by subduction," Tim Johnson, Michael Brown, Nicholas Gardiner, Christopher Kirkland and Hugh Smithies, was published February 27, 2017 in the journal Nature. This work was supported by The Institute of Geoscience Research at Curtin University, Perth, Australia. The content of this article does not necessarily reflect the views of this organization. University of Maryland College of Computer, Mathematical, and Natural Sciences 2300 Symons Hall College Park, MD 20742 http://www. @UMDscience The College of Computer, Mathematical, and Natural Sciences at the University of Maryland educates more than 7,000 future scientific leaders in its undergraduate and graduate programs each year. The college's 10 departments and more than a dozen interdisciplinary research centers foster scientific discovery with annual sponsored research funding exceeding $150 million.


News Article | October 26, 2016
Site: phys.org

Published today in the Monthly Notices of the Royal Astronomical Society, the GaLactic and Extragalactic All-sky MWA, or 'GLEAM' survey, has produced a catalogue of 300,000 galaxies observed by the Murchison Widefield Array (MWA), a $50 million radio telescope located at a remote site north-east of Geraldton. Lead author Dr Natasha Hurley-Walker, from Curtin University and the International Centre for Radio Astronomy Research (ICRAR), said this is the first radio survey to image the sky in such amazing technicolour. "The human eye sees by comparing brightness in three different primary colours – red, green and blue," she said. "GLEAM does rather better than that, viewing the sky in each of 20 primary colours. That's much better than we humans can manage, and it even beats the very best in the animal kingdom, the mantis shrimp, which can see 12 different primary colours." GLEAM is a large-scale, high-resolution survey of the radio sky observed at frequencies from 70 to 230 MHz, observing radio waves that have been travelling through space—some for billions of years. "Our team are using this survey to find out what happens when clusters of galaxies collide," Dr Hurley-Walker said. "We're also able to see the remnants of explosions from the most ancient stars in our galaxy, and find the first and last gasps of supermassive black holes." MWA director Dr Randall Wayth said GLEAM is one of the biggest radio surveys of the sky ever assembled. "The area surveyed is enormous," he said. "Large sky surveys like this are extremely valuable to scientists and they're used across many areas of astrophysics, often in ways the original researchers could never have imagined." Completing the GLEAM survey with the Murchison Widefield Array is a big step on the path to SKA-low, the low frequency part of the international Square Kilometre Array radio telescope to be built in Australia in the coming years. "It's a significant achievement for the MWA telescope and the team of researchers that have worked on the GLEAM survey," Dr Wayth said. "The survey gives us a glimpse of the Universe that SKA-low will be probing once it's built. By mapping the sky in this way we can help fine-tune the design for the SKA and prepare for even deeper observations into the distant Universe." Explore further: Astronomers smash cosmic records to see hydrogen in distant galaxy More information: Original publication, 'GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey I: A low-frequency extragalactic catalogue', published in the Monthly Notices of the Royal Astronomical Society onOctober 27th, 2016. Available from s3-ap-southeast-2.amazonaws.com/icrar.org/wp-content/uploads/2016/10/18223055/GLEAM-Paper_sml.pdf


News Article | February 17, 2017
Site: www.eurekalert.org

A minor planet in the Solar System will officially be known as Bernardbowen from today after Australian citizen science project theSkyNet won a competition to name the celestial body. The minor planet was named by the International Centre for Radio Astronomy Research (ICRAR) in honour of their founding chairman Dr Bernard Bowen. Bernardbowen sits in the asteroid belt between Mars and Jupiter and takes 3.26 Earth years to orbit the Sun. The minor planet was discovered on October 28, 1991, and until now has been known as (6196) 1991 UO4. Based at ICRAR, theSkyNet has been running since 2011 and sees citizen scientists donating their spare computing power to help Australian astronomers uncover the mysteries of the Universe. Its 50,000-odd volunteers entered an International Astronomical Union (IAU) contest to name planets beyond our Solar System. Project founders ICRAR also won the right to name a minor planet within our Solar System. Bernardbowen was one of 17 minor planets to be christened today. Other newly named minor planets include Kagura, after a traditional Shinto theatrical dance, and Mehdia, which is equivalent to the Arabic word for gift. Dr Bowen is renowned as one of the country's finest science administrators and has presided over scientific advances ranging from the oceans to the skies. He was instrumental in the establishment of ICRAR in 2009, and helped bring part of the Square Kilometre Array telescope to Western Australia. A full list of the citation of the minor planets can be found at the IAU Minor Planet Circular. http://bit. Bernardbowen on the Minor Planet Centre site, including an interactive showing its position in the Solar System. http://bit. Images of the orbit of minor planet Bernardbowenare available at http://www. A minor planet is an astronomical object in direct orbit around the Sun that is neither a planet nor exclusively classified as a comet. Minor planets can be dwarf planets, asteroids, trojans, centaurs, Kuiper belt objects, and other trans-Neptunian objects. The International Centre for Radio Astronomy Research (ICRAR) is a joint venture between Curtin University and The University of Western Australia with support and funding from the State Government of Western Australia. http://www. By connecting 100s and 1000s of computers together through the Internet, it's possible to simulate a single machine capable of doing some pretty amazing stuff. That's what theSkyNet is all about - using your spare computing power to process radio astronomy data. http://www. The IAU is the international astronomical organisation that brings together more than 10 000 professional astronomers from almost 100 countries. Its mission is to promote and safeguard the science of astronomy in all its aspects through international cooperation. The IAU also serves as the internationally recognised authority for assigning designations to celestial bodies and the surface features on them. Founded in 1919, the IAU is the world's largest professional body for astronomers. http://www.


News Article | February 21, 2017
Site: www.eurekalert.org

WASHINGTON -- Community-based palliative care -- care delivered at home, not the hospital -- was associated with a 50 percent reduction in emergency department visits for patients in their last year of life. The results of an Australian study were published online February 3rd in Annals of Emergency Medicine ("The Association of Community-Based Palliative Care with Reduced Emergency Department Visits in the Last Year of Life Varies by Patient Factors"). Researchers studied nearly 12,000 records for patients who died of cancer, heart failure, kidney failure, chronic obstructive pulmonary disease and/or liver failures in Western Australia from 2009 to 2010. Dying patients visited the emergency department on average twice a year during their last year of life. The average number of emergency department visits was reduced when patients received palliative care. "It is encouraging that palliative care was associated with reduced emergency department visits for five different diseases, so isn't limited to just cancer or heart failure, for example," said study lead Lorna Rosenwax, PhD. of Curtin University in Perth, Australia. "Most patients who were in their last year of life visited the emergency department at least once, with one person visiting 74 times in the space of a year. Only about one-third (32 percent) of the patients we studied received community-based palliative care but they were much less likely to require emergency medical treatment as a result." The greatest reduction in emergency department visits for patients receiving palliative care was seen in patients who were older, had a partner, lived in major cities, lived in more affluent areas and had no prior history of emergency department visits. The proportion of end-of-life patients who had three or more emergency department visits increased with younger age, geographic remoteness, social disadvantage and end-stage liver failure. End-of-life cancer patients were most likely to receive community-based palliative care (47 percent) while end-of-life liver failure patients were least likely to receive it (13 percent). "Ideally, high-quality palliative care should be able to manage the most common acute symptoms of the dying person without the need for hospitalization," said Ms. Rosenwax. "For these fragile patients, providing care at home should be the goal, but how we get there is the question. When planning community-based palliative care service delivery in the last year of life, it is important to consider patients' social, demographic and health factors." Annals of Emergency Medicine is the peer-reviewed scientific journal for the American College of Emergency Physicians, the national medical society representing emergency medicine. ACEP is committed to advancing emergency care through continuing education, research, and public education. Headquartered in Dallas, Texas, ACEP has 53 chapters representing each state, as well as Puerto Rico and the District of Columbia. A Government Services Chapter represents emergency physicians employed by military branches and other government agencies. For more information, visit http://www. .


CALGARY, ALBERTA--(Marketwired - March 1, 2017) - PROSPECTOR RESOURCES CORP. ("Prospector" or the "Company") (TSX VENTURE:PRR) announces that it has strengthened its management team with the appointments of Mr. Tim Williams as Executive Vice President - COO, Mr. Jose Luis Martinez as Executive Vice President - Corporate Development & Strategy, Mr. Ian Dreyer as Senior Vice President - Geology and Mr. David D'Onofrio as Chief Financial Officer and Corporate Secretary. Tim Williams, who will initially be based in Peru, will provide overall leadership in projects, engineering, construction and mining and will also participate in the technical review of all M&A activities. Prior to joining Prospector Resources Corp., Tim was Vice President Operations for Rio Alto Mining Limited from 2010 to 2015. Tim's responsibilities included overseeing the construction and operation of the La Arena gold mine, and overseeing the construction of the Shahuindo gold mine, both located in Peru. Following the acquisition of Rio Alto Mining Limited by Tahoe Resources Inc. in April 2015, Tim was the Vice President Operations and Country Manager in Peru until August 2016. Prior to his involvement with Rio Alto Mining Limited, Tim managed the El Brocal and the Marcona open pit mining contracts for Stracon - GyM in Peru. Tim has also held senior operating positions in Compania Minera Volcan at their Cerro de Pasco operations also located in Peru. Before arriving in Peru, Tim held mining production roles with Anglo Gold Ashanti at Geita in Tanzania, geotechnical and mine planning roles at WMCs Leintster Nickel Operations and MIM's McArthur River mine both located in Australia. Tim has also worked in the consulting industry with AMC Mining at their Perth, WA office. Tim holds a Masters Degree in Mining Geomechanics, a Bachelors Degree in Mining and Economic Geology, and a Post Graduate Diploma in Mining, from Curtin University, Western Australian School of Mines. He is a Fellow of the Australasian Institute of Mining and Metallurgy. Jose Luis Martinez lives in Toronto, Canada and has extensive Global Banking experience over 23 years in the Canadian financial services sector. Jose Luis is an accomplished Investment Banking professional with extensive Global Banking experience in the Canadian Financial Services sector who is now deploying his capital markets expertise and regional knowledge to make Prospector Resources Corp. a success story. From 2006 to 2016, Jose Luis led business development and relationship management for TD Securities Investment Banking in Latin America, where he had a focus in the Mining sector. Transactions originated included Mergers & Acquisitions Advisory Assignments, Equity Underwriting, and Debt Financing for a wide variety of clients in Canada and Latin America. Prior to this, Jose Luis spent over 12 years covering the Latin American market originating and executing on a wide array of financing transactions for large corporations. He also served as Head of TD Securities' South America Regional Representative Office in Chile. Jose Luis has strong relationships with executives of large public and private companies, as well as controlling shareholders of leading private conglomerates across Latin America. Jose Luis holds an MBA from University of Toronto in Canada and a Bachelor of Business Administration from Universidad de Lima in Peru. Ian Dreyer who is based in Lima, Peru has 30 years of geological and mining related experience ranging from open pit and underground mine production, resource definition to grass roots exploration in Australia, Africa, Indonesia and Latin America. His work in Latin America since 2010 has broadly been in a consulting role, working on deposits in Peru, Chile, Mexico, Brazil and Uruguay. Ian has resided in Lima since 2010 and was a key member of the Rio Alto Mining Limited team that developed the La Arena and Shahuindo gold mines located in Peru. Ian has been involved in the optimization of three major gold deposits: The Golden Mile and its transformation into the "Super Pit", the Mount Charlotte Underground Gold Mine and the Telfer Gold Mine, all located in Australia and brings a mix of technical and operational strengths to the team. Ian holds a BSc in Geology from Curtin University of Western Australia and is a Chartered Professional Geologist (AUSIMM). David D'Onofrio is currently the CFO of a diversified merchant bank focused on providing early stage capital and advisory services to emerging growth companies globally. Mr. D'Onofrio has over 10 years' experience working in public accounting in audit and taxation advisory roles, and has acted as CEO, CFO, Director, Audit Committee member and in other financial advisory positions to a number of private and public enterprises. David is a Chartered Professional Accountant, graduate from Schulich School of Business and holds a Masters of Taxation Degree from the University of Waterloo. Prospector thanks Anthony Jackson for his service over the past years and wishes him continued success on his future endeavours. Alex Black, Prospector Resources Corp. President & CEO stated, "The executive management appointments announced today form the core management team from which our company will grow its future business. The appointments follow on from our stated objective to assemble a highly experienced technical and corporate management team with a solid experience base of developing and building mines and a track record of creating significant shareholder value. We created an enviable business and work culture at Rio Alto Mining Limited that we intend to replicate at Prospector Resources Corp. and have a number of our old management team ready to join our company as we advance our business. We are currently actively reviewing a number of business opportunities that I believe will form a solid base for a new entrant in the precious metals mining space." Prospector is also pleased to announce that it has issued, as part of its variable incentive compensation program, an aggregate of 430,000 Restricted Share Units ("RSUs") and 2,050,000 options to purchase Prospector common shares ("Options"), all pursuant to Prospector's Share Incentive Plan and Stock Option Plan. Of the 430,000 RSUs and 2,050,000 Options, 430,000 RSUs and 1,550,000 Options are being granted to the directors and officers of Prospector, including the individuals announced in this press release. The RSUs, which vest 1/3 equally over a three year period, include a time-based and a performance-based component with a multiplier as determined by the Company's Board of Directors, and entitle the holder to an amount computed by the value of a notional number of Common Shares designated in the award. Each Option entitles the holder to purchase one Prospector common share at a price of $1.02 for a period of five years from the date of grant. The options also vest 1/3 equally over a three year period. The grant of the RSUs and Options are subject to the terms of the Share Incentive Plan and the Stock Option Plan respectively, and final regulatory approval and if applicable, shareholder approval. The focus of Prospector is to compile an attractive portfolio of precious metals assets that can be developed into mines and to assemble a highly experienced technical and corporate management team with a solid experience base of developing and building mines in South America, Central America and South America. Through its strategy of evaluating and acquiring precious metals projects and through a combination of organic exploration and development and strategic acquisitions, the new management team intends to grow the recapitalized Prospector and create long-term shareholder value through the development of high-margin, strong free-cash-flowing mining operations. Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.


The aim of this study was to examine the association between maternal alcohol use disorder and intellectual disability in children. All mothers with an International Classification of Diseases (ICD) 9 and/or 10 alcohol-related diagnosis, a proxy for alcohol use disorder, recorded on the Western Australian health, mental health, and drug and alcohol data sets were identified through the Western Australian Data Linkage Unit (n=5614 non-Aboriginal; n=2912 Aboriginal). A comparison cohort of mothers without an alcohol-related diagnosis was frequency matched on maternal age within maternal Aboriginal status and year of birth of their children. Linkage with the Western Australian Midwives Notification System (1983-2001) identified all births to these mothers (n=10 664 and 7907 respectively). Linkage to the Western Australian Intellectual Disability Database and Register of Developmental Anomalies identified cases of intellectual disability with no identified genetic origin (intellectual disability) (n=1487) and fetal alcohol syndrome (n=66). Odds ratios (ORs) and 95% confidence intervals (CIs) for intellectual disability were calculated using logistic regression incorporating generalized estimating equations and used to estimate population-attributable fractions. At least 3.8% (95% CI 2.84-4.89%) of cases of intellectual disability could be avoided by preventing maternal alcohol use disorder: 1.3% (95% CI 0.81-1.86%) in non-Aboriginal and 15.6% (95% CI 10.85-20.94%) in Aboriginal children. We observed a three-fold increase in the adjusted odds of intellectual disability in children of mothers with an alcohol-related diagnosis recorded during pregnancy (non-Aboriginal OR 2.89, 95% CI 1.62-5.18; Aboriginal OR 3.12, 95% CI 2.13-4.56), with a net excess proportion of 3.7% and 5.5% respectively. One-third (32%) of children diagnosed with fetal alcohol syndrome had intellectual disability. Maternal alcohol use disorder is the leading known risk factor for intellectual disability with no identified genetic origin. © The Authors. Developmental Medicine & Child Neurology © 2012 Mac Keith Press.


News Article | February 20, 2017
Site: www.newscientist.com

The ocean might seem like a quiet place, but listen carefully and you might just hear the sounds of the fish choir. Most of this underwater music comes from soloist fish, repeating the same calls over and over. But when the calls of different fish overlap, they form a chorus. Robert McCauley and colleagues at Curtin University in Perth, Australia, recorded vocal fish in the coastal waters off Port Headland in Western Australia over an 18-month period, and identified seven distinct fish choruses, happening at dawn and at dusk. You can listen to three of them here: The low “foghorn” call is made by the Black Jewfish (Protonibea diacanthus) while the grunting call that researcher Miles Parsons compares to the “buzzer in the Operation board game” comes from a species of Terapontid. The third chorus is a quieter batfish that makes a “ba-ba-ba” call. “I’ve been listening to fish squawks, burble and pops for nearly 30 years now, and they still amaze me with their variety,” says McCauley, who led the research. Sound plays an important role in various fish behaviours such as reproduction, feeding and territorial disputes. Nocturnal predatory fish use calls to stay together to hunt, while fish that are active during the day use sound to defend their territory. “You get the dusk and dawn choruses like you would with the birds in the forest,” says Steve Simpson, a marine biologist at the University of Exeter, UK. The recordings were captured by two sea-noise loggers: the first positioned near the Port Headland shore and the second 21.5 kilometres away in offshore waters. “This is a method that allows us to understand what’s happening at Port Headland 24/7 for a year and a half,” says Simpson. “I don’t know any scuba diver that can stay down there that long!” Listening to choruses over a long period of time allows scientists to monitor fish and their ecosystems, particularly in low visibility waters, such as those off Port Headland. “We are only just beginning to appreciate the complexity involved and still have only a crude idea of what is going on in the undersea acoustic environment,” says McCauley. Read more: Ocean commotion: Protecting sea life from our noise

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