Showing papers by "Macquarie University published in 2015"
Memorial Sloan Kettering Cancer Center1, Institut Gustave Roussy2, Harvard University3, Roswell Park Cancer Institute4, Johns Hopkins University5, Stanford University6, University of Washington7, Vanderbilt University8, Fox Chase Cancer Center9, Macquarie University10, Aarhus University11, University of Helsinki12, The Royal Marsden NHS Foundation Trust13, University of Duisburg-Essen14, Niigata University15, Swansea University16, University of British Columbia17, Bristol-Myers Squibb18, University of Texas MD Anderson Cancer Center19
TL;DR: Overall survival was longer and fewer grade 3 or 4 adverse events occurred with nivolumab than with everolimus among patients with previously treated advanced renal-cell carcinoma.
Abstract: BackgroundNivolumab, a programmed death 1 (PD-1) checkpoint inhibitor, was associated with encouraging overall survival in uncontrolled studies involving previously treated patients with advanced renal-cell carcinoma. This randomized, open-label, phase 3 study compared nivolumab with everolimus in patients with renal-cell carcinoma who had received previous treatment. MethodsA total of 821 patients with advanced clear-cell renal-cell carcinoma for which they had received previous treatment with one or two regimens of antiangiogenic therapy were randomly assigned (in a 1:1 ratio) to receive 3 mg of nivolumab per kilogram of body weight intravenously every 2 weeks or a 10-mg everolimus tablet orally once daily. The primary end point was overall survival. The secondary end points included the objective response rate and safety. ResultsThe median overall survival was 25.0 months (95% confidence interval [CI], 21.8 to not estimable) with nivolumab and 19.6 months (95% CI, 17.6 to 23.1) with everolimus. The haz...
4,643 citations
TL;DR: This work highlights the advances in functionalization strategies that enable the broad utility of upconversion nanocrystals for multimodal imaging, cancer therapy, volumetric displays and photonics.
Abstract: Lanthanide-doped upconversion nanocrystals enable anti-Stokes emission with pump intensities several orders of magnitude lower than required by conventional nonlinear optical techniques. Their exceptional properties, namely large anti-Stokes shifts, sharp emission spectra and long excited-state lifetimes, have led to a diversity of applications. Here, we review upconversion nanocrystals from the perspective of fundamental concepts and examine the technical challenges in relation to emission colour tuning and luminescence enhancement. In particular, we highlight the advances in functionalization strategies that enable the broad utility of upconversion nanocrystals for multimodal imaging, cancer therapy, volumetric displays and photonics.
1,162 citations
TL;DR: In this paper, the evolution of the rest-frame UV luminosity function (LF) from to was mapped using the HST data sets from optical, near-IR, and mid-IR observations.
Abstract: The remarkable Hubble Space Telescope?(HST) data sets from the CANDELS, HUDF09, HUDF12, ERS, and BoRG/HIPPIES programs have allowed us to map the evolution of the rest-frame UV luminosity function (LF) from to . We develop new color criteria that more optimally utilize the full wavelength coverage from the optical, near-IR, and mid-IR observations over our search fields, while simultaneously minimizing the incompleteness and eliminating redshift gaps. We have identified 5859, 3001, 857, 481, 217, and 6 galaxy candidates at , , , , , and , respectively, from the ?1000 arcmin2 area covered by these data sets. This sample of >10,000 galaxy candidates at is by far the largest assembled to date with HST. The selection of 4?8 candidates over the five CANDELS fields allows us to assess the cosmic variance; the largest variations are at . Our new LF determinations at and span a 6 mag baseline and reach to ?16 AB mag. These determinations agree well with previous estimates, but the larger samples and volumes probed here result in a more reliable sampling of galaxies and allow us to reassess the form of the UV LFs. Our new LF results strengthen our earlier findings to significance for a steeper faint-end slope of the UV LF at , with ? evolving from at to at (and at ), consistent with that expected from the evolution of the halo mass function. We find less evolution in the characteristic magnitude M* from to the observed evolution in the LF is now largely represented by changes in . No evidence for a non-Schechter-like form to the z ? 4?8 LFs is found. A simple conditional LF model based on halo growth and evolution in the M/L ratio of halos provides a good representation of the observed evolution.
1,143 citations
Posted Content•
TL;DR: An interpretive framework is presented that analyzes the definitional perspectives and the applications of big data, and a general taxonomy is provided that helps broaden the understanding ofbig data and its role in capturing business value.
Abstract: Big data has the potential to revolutionize the art of management. Despite the high operational and strategic impacts, there is a paucity of empirical research to assess the business value of big data. Drawing on a systematic review and case study findings, this paper presents an interpretive framework that analyzes the definitional perspectives and the applications of big data. The paper also provides a general taxonomy that helps broaden the understanding of big data and its role in capturing business value. The synthesis of the diverse concepts within the literature on big data provides deeper insights into achieving value through big data strategy and implementation.
1,024 citations
TL;DR: A brave new world with a wider view Researchers have long attempted to follow animals as they move through their environment, but such efforts were limited to short distances and times in species large enough to carry large batteries and transmitters, while new technologies have opened up new frontiers in animal tracking remote data collection.
Abstract: BACKGROUND Global aquatic environments are changing profoundly as a result of human actions; consequently, so too are the ways in which organisms are distributing themselves through space and time. Our ability to predict organism and community responses to these alterations will be dependent on knowledge of animal movements, interactions, and how the physiological and environmental processes underlying them shape species distributions. These patterns and processes ultimately structure aquatic ecosystems and provide the wealth of ecosystem services upon which humans depend. Until recently, the vast size, opacity, and dynamic nature of the aquatic realm have impeded our efforts to understand these ecosystems. With rapid technological advancement over the past several decades, a suite of electronic tracking devices (e.g., acoustic and satellite transmitters) that can remotely monitor animals in these challenging environments are now available. Aquatic telemetry technology is rapidly accelerating our ability to observe animal behavior and distribution and, as a consequence, is fundamentally altering our understanding of the structure and function of global aquatic ecosystems. These advances provide the toolbox to define how future global aquatic management practices must evolve. ADVANCES Aquatic telemetry has emerged through technological advances in miniaturization, battery engineering, and software and hardware development, allowing the monitoring of organisms whose habitats range from the poles to the tropics and the photic zone to the abyssal depths. This is enabling the characterization of the horizontal and vertical movements of individuals, populations, and entire communities over scales of meters to tens of thousands of kilometers and over time frames of hours to years and even over the entire lifetimes of individuals. Electronic tags can now be equipped with sensors that measure ambient physical parameters (depth, temperature, conductivity, fluorescence), providing simultaneous monitoring of animals’ environments. By linking telemetry with biologgers (e.g., jaw-motion sensors), it is possible to monitor individual feeding events. In addition, other devices on instrumented animals can communicate with one another, providing insights into predator-prey interactions and social behavior. Coupling telemetry with minute nonlethal biopsy allows understanding of how trophic dynamics, population connectivity, and gene-level basis for organismal health and condition relate to movement. These advances are revolutionizing the scope and scales of questions that can be addressed on the causes and consequences of animal distribution and movement. OUTLOOK Aquatic animal telemetry has advanced rapidly, yet new challenges present themselves in coordination of monitoring across large-spatial scales (ocean basins), data sharing, and data assimilation. The continued advancement of aquatic telemetry lies in establishing and maintaining accessible and cost-effective infrastructure and in promoting multidisciplinary tagging approaches to maximize cost benefits. A united global network and centralized database will provide the mechanism for global telemetry data and will promote a transparent environment for data sharing that will, in turn, increase global communication, scope for collaboration, intellectual advancement, and funding opportunities. An overarching global network will realize the potential of telemetry, which is essential for advancing scientific knowledge and effectively managing globally shared aquatic resources and their ecosystems in the face of mounting human pressures and environmental change.
1,011 citations
TL;DR: It is suggested that the relative abundance of the clinical class 1 integron-integrase gene, intI1, is a good proxy for pollution because it is linked to genes conferring resistance to antibiotics, disinfectants and heavy metals.
Abstract: Around all human activity, there are zones of pollution with pesticides, heavy metals, pharmaceuticals, personal care products and the microorganisms associated with human waste streams and agriculture. This diversity of pollutants, whose concentration varies spatially and temporally, is a major challenge for monitoring. Here, we suggest that the relative abundance of the clinical class 1 integron-integrase gene, intI1, is a good proxy for pollution because: (1) intI1 is linked to genes conferring resistance to antibiotics, disinfectants and heavy metals; (2) it is found in a wide variety of pathogenic and nonpathogenic bacteria; (3) its abundance can change rapidly because its host cells can have rapid generation times and it can move between bacteria by horizontal gene transfer; and (4) a single DNA sequence variant of intI1 is now found on a wide diversity of xenogenetic elements, these being complex mosaic DNA elements fixed through the agency of human selection. Here we review the literature examining the relationship between anthropogenic impacts and the abundance of intI1, and outline an approach by which intI1 could serve as a proxy for anthropogenic pollution.
919 citations
University of California, San Diego1, Harvard University2, ETH Zurich3, Macquarie University4, Max Planck Society5, Albert Einstein College of Medicine6, Johns Hopkins University7, University of Georgia8, Osaka University9, Discovery Institute10, University of California, Santa Barbara11, Stanford University12, University of California, Davis13, Utrecht University14, University of Giessen15, University of Grenoble16, National Institutes of Health17, Scripps Research Institute18, Kyoto University19, Soka University of America20, Imperial College London21, National Institute of Advanced Industrial Science and Technology22, Washington University in St. Louis23
TL;DR: Author(s): Varki, Ajit; Cummings, Richard D; Aebi, Markus; Packer, Nicole H; Seeberger, Peter H; Esko, Jeffrey D; Stanley, Pamela; Hart, Gerald; Darvill, Alan; Kinoshita, Taroh; Prestegard, James J; Schnaar, Ronald L; Freeze, Hudson H; Marth, Jamey D; Bertozzi, Carolyn R.
Abstract: Author(s): Varki, Ajit; Cummings, Richard D; Aebi, Markus; Packer, Nicole H; Seeberger, Peter H; Esko, Jeffrey D; Stanley, Pamela; Hart, Gerald; Darvill, Alan; Kinoshita, Taroh; Prestegard, James J; Schnaar, Ronald L; Freeze, Hudson H; Marth, Jamey D; Bertozzi, Carolyn R; Etzler, Marilynn E; Frank, Martin; Vliegenthart, Johannes Fg; Lutteke, Thomas; Perez, Serge; Bolton, Evan; Rudd, Pauline; Paulson, James; Kanehisa, Minoru; Toukach, Philip; Aoki-Kinoshita, Kiyoko F; Dell, Anne; Narimatsu, Hisashi; York, William; Taniguchi, Naoyuki; Kornfeld, Stuart
735 citations
TL;DR: The present study aims to comprehensively review the available literature and evidence for different lumbar inter body fusion (LIF) techniques, and proposes a set of recommendations and guidelines for the indications for interbody fusion options.
Abstract: Degenerative disc and facet joint disease of the lumbar spine is common in the ageing population, and is one of the most frequent causes of disability Lumbar spondylosis may result in mechanical back pain, radicular and claudicant symptoms, reduced mobility and poor quality of life Surgical interbody fusion of degenerative levels is an effective treatment option to stablize the painful motion segment, and may provide indirect decompression of the neural elements, restore lordosis and correct deformity The surgical options for interbody fusion of the lumbar spine include: posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), minimally invasive transforaminal lumbar interbody fusion (MI-TLIF), oblique lumbar interbody fusion/anterior to psoas (OLIF/ATP), lateral lumbar interbody fusion (LLIF) and anterior lumbar interbody fusion (ALIF) The indications may include: discogenic/facetogenic low back pain, neurogenic claudication, radiculopathy due to foraminal stenosis, lumbar degenerative spinal deformity including symptomatic spondylolisthesis and degenerative scoliosis In general, traditional posterior approaches are frequently used with acceptable fusion rates and low complication rates, however they are limited by thecal sac and nerve root retraction, along with iatrogenic injury to the paraspinal musculature and disruption of the posterior tension band Minimally invasive (MIS) posterior approaches have evolved in an attempt to reduce approach related complications Anterior approaches avoid the spinal canal, cauda equina and nerve roots, however have issues with approach related abdominal and vascular complications In addition, lateral and OLIF techniques have potential risks to the lumbar plexus and psoas muscle The present study aims firstly to comprehensively review the available literature and evidence for different lumbar interbody fusion (LIF) techniques Secondly, we propose a set of recommendations and guidelines for the indications for interbody fusion options Thirdly, this article provides a description of each approach, and illustrates the potential benefits and disadvantages of each technique with reference to indication and spine level performed
653 citations
University of Sydney1, Australian Astronomical Observatory2, Australian National University3, University of New South Wales4, Macquarie University5, University of Ljubljana6, University of Southern Queensland7, Max Planck Society8, Monash University9, University of Cambridge10, INAF11, Joint Institute for Nuclear Astrophysics12, University of Minnesota13, University of Western Australia14, Uppsala University15, Harvard University16
TL;DR: The Galactic Archaeology with HERMES (GALAH) survey is a large high-resolution spectroscopic survey using the newly commissioned High Efficiency and Resolution Multi-element Spectrograph (HERMES) on the Anglo-Australian Telescope as discussed by the authors.
Abstract: The Galactic Archaeology with HERMES (GALAH) survey is a large high-resolution spectroscopic survey using the newly commissioned High Efficiency and Resolution Multi-Element Spectrograph (HERMES) on the Anglo-Australian Telescope. The HERMES spectrograph provides high-resolution (R ~ 28 000) spectra in four passbands for 392 stars simultaneously over a 2 deg field of view. The goal of the survey is to unravel the formation and evolutionary history of the Milky Way, using fossil remnants of ancient star formation events which have been disrupted and are now dispersed throughout the Galaxy. Chemical tagging seeks to identify such dispersed remnants solely from their common and unique chemical signatures; these groups are unidentifiable from their spatial, photometric or kinematic properties. To carry out chemical tagging, the GALAH survey will acquire spectra for a million stars down to V ~ 14. The HERMES spectra of FGK stars contain absorption lines from 29 elements including light proton-capture elements, α-elements, odd-Z elements, iron-peak elements and n-capture elements from the light and heavy s-process and the r-process. This paper describes the motivation and planned execution of the GALAH survey, and presents some results on the first-light performance of HERMES.
630 citations
Princeton University1, University of Idaho2, National Center for Atmospheric Research3, United States Geological Survey4, University of California, Santa Barbara5, United States Forest Service6, University of Montana7, University of Florida8, University of Arizona9, Los Alamos National Laboratory10, University of Wisconsin-Madison11, Macquarie University12
TL;DR: Using data sets from the western USA and associated studies, a framework is presented for determining the relative contribution of drought stress, insect attack, and their interactions, critical for modeling mortality in future climates.
Abstract: Climate change is expected to drive increased tree mortality through drought, heat stress, and insect attacks, with manifold impacts on forest ecosystems. Yet, climate-induced tree mortality and biotic disturbance agents are largely absent from process-based ecosystem models. Using data sets from the western USA and associated studies, we present a framework for determining the relative contribution of drought stress, insect attack, and their interactions, which is critical for modeling mortality in future climates. We outline a simple approach that identifies the mechanisms associated with two guilds of insects - bark beetles and defoliators - which are responsible for substantial tree mortality. We then discuss cross-biome patterns of insect-driven tree mortality and draw upon available evidence contrasting the prevalence of insect outbreaks in temperate and tropical regions. We conclude with an overview of tools and promising avenues to address major challenges. Ultimately, a multitrophic approach that captures tree physiology, insect populations, and tree-insect interactions will better inform projections of forest ecosystem responses to climate change.
602 citations
TL;DR: This review paper is the first of its kind with the aim of providing a “one-stop” information source and a selection guide on impedance-source networks for power conversion for researchers, designers, and application engineers.
Abstract: Impedance networks cover the entire of electric power conversion from dc (converter, rectifier), ac (inverter), to phase and frequency conversion (ac-ac) in a wide range of applications. Various converter topologies have been reported in the literature to overcome the limitations and problems of the traditional voltage source, current source as well as various classical buck-boost, unidirectional, and bidirectional converter topologies. Proper implementation of the impedance-source network with appropriate switching configurations and topologies reduces the number of power conversion stages in the system power chain, which may improve the reliability and performance of the power system. The first part of this paper provides a comprehensive review of the various impedance-source-networks-based power converters and discusses the main topologies from an application point of view. This review paper is the first of its kind with the aim of providing a “one-stop” information source and a selection guide on impedance-source networks for power conversion for researchers, designers, and application engineers. A comprehensive review of various modeling, control, and modulation techniques for the impedance-source converters/inverters will be presented in Part II.
University of Queensland1, Patuxent Wildlife Research Center2, National University of Singapore3, United States Geological Survey4, University of Cambridge5, University of Wollongong6, National Institute of Water and Atmospheric Research7, Macquarie University8, Vietnam National University, Ho Chi Minh City9
TL;DR: It is found that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of sea-level rise, but for 69 per cent of the study sites the current rate of sea level rise exceeded the soil surface elevation gain.
Abstract: Sea-level rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves. Mangrove forests have the capacity to keep pace with sea-level rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth. The Indo-Pacific region holds most of the world's mangrove forests, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers. This decline is of particular concern because the Indo-Pacific region is expected to have variable, but high, rates of future sea-level rise. Here we analyse recent trends in mangrove surface elevation changes across the Indo-Pacific region using data from a network of surface elevation table instruments. We find that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of sea-level rise, but for 69 per cent of our study sites the current rate of sea-level rise exceeded the soil surface elevation gain. We also present a model based on our field data, which suggests that mangrove forests at sites with low tidal range and low sediment supply could be submerged as early as 2070.
European Southern Observatory1, Liverpool John Moores University2, University of St Andrews3, University of Western Australia4, Max Planck Society5, Ames Research Center6, Australian Astronomical Observatory7, University of the Western Cape8, Durham University9, University of Sussex10, University of Melbourne11, University of Nottingham12, University of Sydney13, Monash University, Clayton campus14, University of Queensland15, University of Edinburgh16, University of Central Lancashire17, Australian National University18, University of Turku19, University of Canterbury20, University of Hertfordshire21, University of Oxford22, Leiden University23, Institute of Cosmology and Gravitation, University of Portsmouth24, National Institute of Astrophysics, Optics and Electronics25, Macquarie University26, National Autonomous University of Mexico27, Carnegie Institution for Science28, University of Bristol29, University of Hull30, Romanian Academy31, Queen Mary University of London32, University of Innsbruck33
TL;DR: The Galaxy And Mass Assembly (GAMA) survey as mentioned in this paper is one of the largest contemporary spectroscopic surveys of low redshift galaxies, covering an area of ∼286 deg2 (split among five survey regions) down to a limiting magnitude of r < 19.8 mag, and collecting spectra and reliable redshifts for 238'000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope.
Abstract: The Galaxy And Mass Assembly (GAMA) survey is one of the largest contemporary spectroscopic surveys of low redshift galaxies. Covering an area of ∼286 deg2 (split among five survey regions) down to a limiting magnitude of r < 19.8 mag, we have collected spectra and reliable redshifts for 238 000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope. In addition, we have assembled imaging data from a number of independent surveys in order to generate photometry spanning the wavelength range 1 nm–1 m. Here, we report on the recently completed spectroscopic survey and present a series of diagnostics to assess its final state and the quality of the redshift data. We also describe a number of survey aspects and procedures, or updates thereof, including changes to the input catalogue, redshifting and re-redshifting, and the derivation of ultraviolet, optical and near-infrared photometry. Finally, we present the second public release of GAMA data. In this release, we provide input catalogue and targeting information, spectra, redshifts, ultraviolet, optical and near-infrared photometry, single-component Sersic fits, stellar masses, Hα-derived star formation rates, environment information, and group properties for all galaxies with r < 19.0 mag in two of our survey regions, and for all galaxies with r < 19.4 mag in a third region (72 225 objects in total). The data base serving these data is available at http://www.gama-survey.org/.
TL;DR: In this paper, a simple, efficient method for simulating Hamiltonian dynamics on a quantum computer by approximating the truncated Taylor series of the evolution operator is described, which can simulate the time evolution of a wide variety of physical systems.
Abstract: We describe a simple, efficient method for simulating Hamiltonian dynamics on a quantum computer by approximating the truncated Taylor series of the evolution operator. Our method can simulate the time evolution of a wide variety of physical systems. As in another recent algorithm, the cost of our method depends only logarithmically on the inverse of the desired precision, which is optimal. However, we simplify the algorithm and its analysis by using a method for implementing linear combinations of unitary operations together with a robust form of oblivious amplitude amplification.
University of Sydney1, Australian Astronomical Observatory2, University of Western Australia3, University of St Andrews4, University of Queensland5, Swinburne University of Technology6, Australian National University7, University of Melbourne8, Liverpool John Moores University9, Rutgers University10, University of North Carolina at Chapel Hill11, University of Oxford12, Durham University13, University of Hawaii14, European Southern Observatory15, Macquarie University16, Indian Institute of Science Education and Research, Mohali17, Leibniz Institute for Astrophysics Potsdam18
TL;DR: The SAMI Galaxy Survey as discussed by the authors is a 3-year survey of 3400 galaxies with the Sydney-AAO Multi-Object Integral Field Spectrograph (SAMI) on the Anglo-Australian Telescope (AAT).
Abstract: The SAMI Galaxy Survey will observe 3400 galaxies with the Sydney-AAO Multi- object Integral-field spectrograph (SAMI) on the Anglo-Australian Telescope (AAT) in a 3-year survey which began in 2013. We present the throughput of the SAMI system, the science basis and specifications for the target selection, the survey observation plan and the combined properties of the selected galaxies. The survey includes four volume-limited galaxy samples based on cuts in a proxy for stellar mass, along with low-stellar-mass dwarf galaxies all selected from the Galaxy And Mass Assembly (GAMA) survey. The GAMA regions were selected because of the vast array of ancillary data available, including ultraviolet through to radio bands. These fields are on the celestial equator at 9, 12, and 14.5 hours, and cover a total of 144 square degrees (in GAMA-I). Higher density environments are also included with the addition of eight clusters. The clusters have spectroscopy from 2dFGRS and SDSS and photometry in regions covered by the Sloan Digital Sky Survey (SDSS) and/or VLT Survey Telescope/ATLAS. The aim is to cover a broad range in stellar mass and environment, and therefore the primary survey targets cover redshifts 0.004 < z < 0.095, magnitudes rpet < 19.4, stellar masses 107– 1012M⊙, and environments from isolated field galaxies through groups to clusters of _ 1015M⊙.
National Institutes of Natural Sciences, Japan1, Macquarie University2, University of Arizona3, PSL Research University4, Ames Research Center5, California Institute of Technology6, University of Sydney7, University of Liège8, Hokkaido University9, Kyoto University10, University of Tokyo11, Search for extraterrestrial intelligence12, University of California, Berkeley13, University of Grenoble14, European Southern Observatory15
TL;DR: The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument as discussed by the authors is a multiband instrument which makes use of light from 600 to 2500 nm, allowing for coronagraphic direct exoplanet imaging of the inner 3λ/D from the stellar host.
Abstract: The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument is a multipurpose high-contrast imaging platform designed for the discovery and detailed characterization of exoplanetary systems and serves as a testbed for high-contrast imaging technologies for ELTs. It is a multiband instrument which makes use of light from 600 to 2500 nm, allowing for coronagraphic direct exoplanet imaging of the inner 3λ/D from the stellar host. Wavefront sensing and control are key to the operation of SCExAO. A partial correction of low-order modes is provided by Subaru's facility adaptive optics system with the final correction, including high-order modes, implemented downstream by a combination of a visible pyramid wavefront sensor and a 2000-element deformable mirror. The well-corrected NIR (y-K bands) wavefronts can then be injected into any of the available coronagraphs, including but not limited to the phase-induced amplitude apodization and the vector vortex coronagraphs, both of which offer an inner working angle as low as 1λ/D. Noncommon path, low-order aberrations are sensed with a coronagraphic low-order wavefront sensor in the infrared (IR). Low noise, high frame rate NIR detectors allow for active speckle nulling and coherent differential imaging, while the HAWAII 2RG detector in the HiCIAO imager and/or the CHARIS integral field spectrograph (from mid-2016) can take deeper exposures and/or perform angular, spectral, and polarimetric differential imaging. Science in the visible is provided by two interferometric modules: VAMPIRES and FIRST, which enable subdiffraction limited imaging in the visible region with polarimetric and spectroscopic capabilities respectively. We describe the instrument in detail and present preliminary results both on-sky and in the laboratory.
Australian Astronomical Observatory1, Macquarie University2, California Institute of Technology3, University of California, Berkeley4, Paris Diderot University5, University of Oxford6, University of Toledo7, University of Hertfordshire8, Leiden University9, European Southern Observatory10, École normale supérieure de Lyon11, University of Edinburgh12, Leibniz Institute for Astrophysics Potsdam13, Kapteyn Astronomical Institute14, Max Planck Society15, University of Sydney16, Commonwealth Scientific and Industrial Research Organisation17, ASTRON18, University of St Andrews19, New Mexico Institute of Mining and Technology20, Academia Sinica Institute of Astronomy and Astrophysics21
TL;DR: In this article, the stellar population content of early-type galaxies from the ATLAS^(3D) survey is analyzed using spectra integrated within apertures covering up to one effective radius.
Abstract: We present the stellar population content of early-type galaxies from the ATLAS^(3D) survey. Using spectra integrated within apertures covering up to one effective radius, we apply two methods: one based on measuring line-strength indices and applying single stellar population (SSP) models to derive SSP-equivalent values of stellar age, metallicity, and alpha enhancement; and one based on spectral fitting to derive non-parametric star formation histories, mass-weighted average values of age, metallicity, and half-mass formation time-scales. Using homogeneously derived effective radii and dynamically determined galaxy masses, we present the distribution of stellar population parameters on the Mass Plane (M_(JAM), σ_e, R^(maj)_e), showing that at fixed mass, compact early-type galaxies are on average older, more metal-rich, and more alpha-enhanced than their larger counterparts. From non-parametric star formation histories, we find that the duration of star formation is systematically more extended in lower mass objects. Assuming that our sample represents most of the stellar content of today's local Universe, approximately 50 per cent of all stars formed within the first 2 Gyr following the big bang. Most of these stars reside today in the most massive galaxies (>10^(10.5) M⊙), which themselves formed 90 per cent of their stars by z ∼ 2. The lower mass objects, in contrast, have formed barely half their stars in this time interval. Stellar population properties are independent of environment over two orders of magnitude in local density, varying only with galaxy mass. In the highest density regions of our volume (dominated by the Virgo cluster), galaxies are older, alpha-enhanced, and have shorter star formation histories with respect to lower density regions.
Macquarie University1, University of Western Sydney2, Imperial College London3, University of Technology, Sydney4, University of Lleida5, Commonwealth Scientific and Industrial Research Organisation6, University of Antwerp7, University of Gothenburg8, Swedish University of Agricultural Sciences9, Lund University10, James Cook University11, Kansas State University12, Colorado State University13, University of Paris-Sud14, Brookhaven National Laboratory15, Oak Ridge National Laboratory16, Tuscia University17, Tohoku University18, Kyoto University19, University of Exeter20, Institut national de la recherche agronomique21, International Sleep Products Association22, University of Melbourne23, University of Auckland24, Spanish National Research Council25, University of Edinburgh26, Charles Darwin University27, Forestry Commission28, Ishikawa Prefectural University29, University of Helsinki30, Obihiro University of Agriculture and Veterinary Medicine31, University of New Mexico32, Federal University of Pará33, Technical University of Denmark34, Pontifical Catholic University of Peru35, University of Oxford36, Northeast Normal University37
TL;DR: In this paper, the authors present a database of globally distributed stomatal conductance (g(s) obtained in the field for a wide range of plant functional types (PFTs) and biomes.
Abstract: Stomatal conductance (g(s)) is a key land-surface attribute as it links transpiration, the dominant component of global land evapotranspiration, and photosynthesis, the driving force of the global carbon cycle. Despite the pivotal role of g(s) in predictions of global water and carbon cycle changes, a global-scale database and an associated globally applicable model of g(s) that allow predictions of stomatal behaviour are lacking. Here, we present a database of globally distributed g(s) obtained in the field for a wide range of plant functional types (PFTs) and biomes. We find that stomatal behaviour differs among PFTs according to their marginal carbon cost of water use, as predicted by the theory underpinning the optimal stomatal model(1) and the leaf and wood economics spectrum(2,3). We also demonstrate a global relationship with climate. These findin g(s) provide a robust theoretical framework for understanding and predicting the behaviour of g(s) across biomes and across PFTs that can be applied to regional, continental and global-scale modelling of ecosystem productivity, energy balance and ecohydrological processes in a future changing climate.
J. W. Ferry Slik, Víctor Arroyo-Rodríguez1, Shin-ichiro Aiba2, Patricia Alvarez-Loayza3 +173 more•Institutions (74)
TL;DR: It is shown that most tree species are extremely rare, meaning that they may be under serious risk of extinction at current deforestation rates, and a methodological framework for estimating species richness in trees is provided that may help refine species richness estimates of tree-dependent taxa.
Abstract: The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher's alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between similar to 40,000 and similar to 53,000, i.e., at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of similar to 19,000-25,000 tree species. Continental Africa is relatively depauperate with a minimum of similar to 4,500-6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa.
TL;DR: In this article, a comprehensive database of zircon composition in West Australian magmatic rocks reveals negative correlations between both U and Th ZIRcon/whole rock ratio and the zircons saturation temperature, with the observed change with temperature less for U(zircon/Whole rock) than for Th(Zircon-whole-rock).
Paris Diderot University1, PSL Research University2, European Southern Observatory3, University of Oxford4, California Institute of Technology5, University of California, Berkeley6, University of Toledo7, Leiden University8, École normale supérieure de Lyon9, University of Edinburgh10, Leibniz Institute for Astrophysics Potsdam11, Australian Astronomical Observatory12, Macquarie University13, ASTRON14, Kapteyn Astronomical Institute15, Max Planck Society16, University of Hertfordshire17, University of Sydney18, Australia Telescope National Facility19, University of St Andrews20, Academia Sinica Institute of Astronomy and Astrophysics21, New Mexico Institute of Mining and Technology22
TL;DR: In this article, the authors presented a catalogue of 92 galaxies from the ATLAS^(3D) sample, which are located in low- to medium-density environments, which achieved a gain of several magnitudes in the limiting surface brightness with respect to classical imaging surveys.
Abstract: Galactic archaeology based on star counts is instrumental to reconstruct the past mass assembly of Local Group galaxies. The development of new observing techniques and data reduction, coupled with the use of sensitive large field of view cameras, now allows us to pursue this technique in more distant galaxies exploiting their diffuse low surface brightness (LSB) light. As part of the ATLAS^(3D) project, we have obtained with the MegaCam camera at the Canada–France–Hawaii Telescope extremely deep, multiband images of nearby early-type galaxies (ETGs). We present here a catalogue of 92 galaxies from the ATLAS^(3D) sample, which are located in low- to medium-density environments. The observing strategy and data reduction pipeline, which achieve a gain of several magnitudes in the limiting surface brightness with respect to classical imaging surveys, are presented. The size and depth of the survey are compared to other recent deep imaging projects. The paper highlights the capability of LSB-optimized surveys at detecting new prominent structures that change the apparent morphology of galaxies. The intrinsic limitations of deep imaging observations are also discussed, among those, the contamination of the stellar haloes of galaxies by extended ghost reflections, and the cirrus emission from Galactic dust. The detection and systematic census of fine structures that trace the present and past mass assembly of ETGs are one of the prime goals of the project. We provide specific examples of each type of observed structures – tidal tails, stellar streams and shells – and explain how they were identified and classified. We give an overview of the initial results. The detailed statistical analysis will be presented in future papers.
TL;DR: The current approach to patient safety, labelled Safety I, is predicated on a 'find and fix' model, which identifies things going wrong, after the event, and aims to stamp them out, in order to ensure that the number of errors is as low as possible as discussed by the authors.
Abstract: The current approach to patient safety, labelled Safety I, is predicated on a 'find and fix' model. It identifies things going wrong, after the event, and aims to stamp them out, in order to ensure that the number of errors is as low as possible. Healthcare is much more complex than such a linear model suggests. We need to switch the focus to what we have come to call Safety II: a concerted effort to enable things to go right more often. The key is to appreciate that healthcare is resilient to a large extent, and everyday performance succeeds much more often than it fails. Clinicians constantly adjust what they do to match the conditions. Facilitating work flexibility, and actively trying to increase the capacity of clinicians to deliver more care more effectively, is key to this new paradigm. At its heart, proactive safety management focuses on how everyday performance usually succeeds rather than on why it occasionally fails, and actively strives to improve the former rather than simply preventing the latter.
Australian National University1, University of Western Sydney2, University of Minnesota3, Carnegie Institution for Science4, Institut national de la recherche agronomique5, Max Planck Society6, Commonwealth Scientific and Industrial Research Organisation7, James Cook University8, Pontifical Catholic University of Peru9, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto10, Purdue University11, National and Kapodistrian University of Athens12, Princeton University13, University of Leeds14, Lamont–Doherty Earth Observatory15, University of Edinburgh16, University of New Hampshire17, University of Western Australia18, Imperial College London19, University of Waikato20, Environmental Change Institute21, Macquarie University22, University of Exeter23, University of Toronto24, National Parks Board25, Estonian University of Life Sciences26, Wageningen University and Research Centre27, Colorado State University28, Smithsonian Tropical Research Institute29, University of Florida30, University of Canterbury31, University of Regina32, Spanish National Research Council33, University of Peradeniya34, Leipzig University35, Chinese Academy of Sciences36
TL;DR: A new global database of Rdark and associated leaf traits is analyzed and values at any given Vcmax or leaf nitrogen concentration were higher in herbs than in woody plants, and variation in Rdark among species and across global gradients in T and aridity is highlighted.
Abstract: Leaf dark respiration (R-dark) is an important yet poorly quantified component of the global carbon cycle. Given this, we analyzed a new global database of R-dark and associated leaf traits. Data for 899 species were compiled from 100 sites (from the Arctic to the tropics). Several woody and nonwoody plant functional types (PFTs) were represented. Mixed-effects models were used to disentangle sources of variation in R-dark. Area-based R-dark at the prevailing average daily growth temperature (T) of each siteincreased only twofold from the Arctic to the tropics, despite a 20 degrees C increase in growing T (8-28 degrees C). By contrast, R-dark at a standard T (25 degrees C, R-dark(25)) was threefold higher in the Arctic than in the tropics, and twofold higher at arid than at mesic sites. Species and PFTs at cold sites exhibited higher R-dark(25) at a given photosynthetic capacity (V-cmax(25)) or leaf nitrogen concentration ([N]) than species at warmer sites. R-dark(25) values at any given V-cmax(25) or [N] were higher in herbs than in woody plants. The results highlight variation in R-dark among species and across global gradients in T and aridity. In addition to their ecological significance, the results provide a framework for improving representation of R-dark in terrestrial biosphere models (TBMs) and associated land-surface components of Earth system models (ESMs).
TL;DR: This paper provides as a guide and quick reference for researchers and practicing engineers in deciding which control and modulation method to consider for an application in a given topology at a certain power level, switching frequency and demanded dynamic response.
Abstract: Impedance-source networks cover the entire spectrum of electric power conversion applications (dc-dc, dc-ac, ac-dc, ac-ac) controlled and modulated by different modulation strategies to generate the desired dc or ac voltage and current at the output. A comprehensive review of various impedance-source-network-based power converters has been covered in a previous paper and main topologies were discussed from an application point of view. Now Part II provides a comprehensive review of the most popular control and modulation strategies for impedance-source network-based power converters/inverters. These methods are compared in terms of theoretical complexity and performance, when applied to the respective switching topologies. Further, this paper provides as a guide and quick reference for researchers and practicing engineers in deciding which control and modulation method to consider for an application in a given topology at a certain power level, switching frequency and demanded dynamic response.
TL;DR: An unprecedented worldwide database including 831 within-canopy gradients with standardized light estimates for 304 species belonging to major vascular plant functional types is constructed, and an old enigma of the role of mass- vs area-based traits in vegetation acclimation is solved.
Abstract: Extensive within-canopy light gradients importantly affect the photosynthetic productivity of leaves in different canopy positions and lead to light-dependent increases in foliage photosynthetic capacity per area (AA). However, the controls on AA variations by changes in underlying traits are poorly known. We constructed an unprecedented worldwide database including 831 within-canopy gradients with standardized light estimates for 304 species belonging to major vascular plant functional types, and analyzed within-canopy variations in 12 key foliage structural, chemical and physiological traits by quantitative separation of the contributions of different traits to photosynthetic acclimation. Although the light-dependent increase in AA is surprisingly similar in different plant functional types, they differ fundamentally in the share of the controls on AA by constituent traits. Species with high rates of canopy development and leaf turnover, exhibiting highly dynamic light environments, actively change AA by nitrogen reallocation among and partitioning within leaves. By contrast, species with slow leaf turnover exhibit a passive AA acclimation response, primarily determined by the acclimation of leaf structure to growth light. This review emphasizes that different combinations of traits are responsible for within-canopy photosynthetic acclimation in different plant functional types, and solves an old enigma of the role of mass- vs area-based traits in vegetation acclimation.
TL;DR: In this paper, the authors employ ion beam polishing and high resolution scanning electron microscopy to show that primary organic matter (OM)-hosted pores are common in thermally immature shales.
TL;DR: The review compares mechanisms of antibiotic resistance at cellular and community levels in the light of past and present antibiotic discovery efforts and concludes that community level resistance provided by biofilms is distinct from resistance mechanisms that operate at a cellular level.
Abstract: Bacterial resistance is a rapidly escalating threat to public health as our arsenal of effective antibiotics dwindles. Therefore, there is an urgent need for new antibiotics. Drug discovery has historically focused on bacteria growing in planktonic cultures. Many antibiotics were originally developed to target individual bacterial cells, being assessed in vitro against microorganisms in a planktonic mode of life. However, towards the end of the 20th century it became clear that many bacteria live as complex communities called biofilms in their natural habitat, and this includes habitats within a human host. The biofilm mode of life provides advantages to microorganisms, such as enhanced resistance towards environmental stresses, including antibiotic challenge. The community level resistance provided by biofilms is distinct from resistance mechanisms that operate at a cellular level, and cannot be overlooked in the development of novel strategies to combat infectious diseases. The review compares mechanisms of antibiotic resistance at cellular and community levels in the light of past and present antibiotic discovery efforts. Future perspectives on novel strategies for treatment of biofilm-related infectious diseases are explored.
TL;DR: Hippocampal volume was reduced in subjects with PTSD, with a greater reduction in the left hippocampus, and bilateral volume reductions in the ACC may underpin the attentional deficits and inabilities to modulate emotions that are characteristically associated with PTSD patients.
Abstract: Posttraumatic stress disorder (PTSD) is a debilitating condition associated with mild to moderate cognitive impairment and with a prevalence rate of up to 22% in veterans This systematic review and quantitative meta-analysis explore volumetric differences of three key structural brain regions (hippocampus, amygdala and anterior cingulate cortex (ACC)), all of which have been implicated in dysfunction of both salience network (SN) and default mode network (DMN) in PTSD sufferers A literature search was conducted in Embase, Medline, PubMed and PsycINFO in May 2013 Fifty-nine volumetric analyses from 44 articles were examined and included (36 hippocampus, 14 amygdala and nine ACC) with n=846 PTSD participants, n=520 healthy controls (HCs) and n=624 traumatised controls (TCs) Nine statistical tests were performed for each of the three regions of interest (ROIs), measuring volume differences in PTSD subjects, healthy and traumatised controls Hippocampal volume was reduced in subjects with PTSD, with a greater reduction in the left hippocampus A medium effect size reduction was found in bilateral amygdala volume when compared with findings in healthy controls; however, no significant differences in amygdala volume between PTSD subjects and trauma-exposed controls were found Significant volume reductions were found bilaterally in the ACC While often well matched with their respective control groups, the samples of PTSD subjects composed from the source studies used in the meta-analyses are limited in their homogeneity The current findings of reduced hippocampal volume in subjects with PTSD are consistent with the existing literature Amygdala volumes did not show significant reductions in PTSD subjects when compared with volumes in trauma-exposed controls-congruous with reported symptoms of hypervigilance and increased propensity in acquisition of conditioned fear memories-but a significant reduction was found in the combined left and right hemisphere volume analysis when compared with healthy controls Bilateral volume reductions in the ACC may underpin the attentional deficits and inabilities to modulate emotions that are characteristically associated with PTSD patients Language: en
TL;DR: Key findings include the importance of designing for active learning, the need to select and utilise technologies appropriately to meet communicative requirements, varying degrees of co-presence depending on technological and human factors, and heightened cognitive load.
Abstract: Increasingly, universities are using technology to provide students with more flexible modes of participation. This article presents a cross-case analysis of blended synchronous learning environments—contexts where remote students participated in face-to-face classes through the use of rich-media synchronous technologies such as video conferencing, web conferencing, and virtual worlds. The study examined how design and implementation factors influenced student learning activity and perceived learning outcomes, drawing on a synthesis of student, teacher, and researcher observations collected before, during, and after blended synchronous learning lessons. Key findings include the importance of designing for active learning, the need to select and utilise technologies appropriately to meet communicative requirements, varying degrees of co-presence depending on technological and human factors, and heightened cognitive load. Pedagogical, technological, and logistical implications are presented in the form of a Blended Synchronous Learning Design Framework that is grounded in the results of the study.
TL;DR: The data demonstrate that ctDNA is a useful biomarker of response to kinase inhibitor therapy and can be used to monitor tumor evolution and detect the early appearance of resistance effectors.
Abstract: // Elin S. Gray 1 , Helen Rizos 2,8 , Anna L. Reid 1 , Suzanah C. Boyd 2,8 , Michelle R. Pereira 1 , Johnny Lo 3 , Varsha Tembe 4 , James Freeman 1 , Jenny H.J. Lee 4,5 , Richard A. Scolyer 6,8 , Kelvin Siew 9 , Chris Lomma 9 , Adam Cooper 5 , Muhammad A. Khattak 10,11 , Tarek M. Meniawy 9,11 , Georgina V. Long 7,8 , Matteo S. Carlino 5,8 , Michael Millward 9,11 and Melanie Ziman 1,12 1 School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia 2 Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales, Australia 3 School of Engineering, Edith Cowan University, Joondalup, Western Australia, Australia 4 Centre for Cancer Research, The University of Sydney at Westmead Millennium Institute, Westmead Hospital, Westmead, New South Wales, Australia 5 Department of Medical Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Westmead, New South Wales, Australia 6 Disciplines of Pathology, The University of Sydney, Sydney, New South Wales, Australia 7 Medicine, Sydney Medical School, The University of Sydney, Sydney, New South Wales, Australia 8 Melanoma Institute Australia, Sydney, New South Wales, Australia 9 Department of Medical Oncology, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia 10 Department of Medical Oncology, Fiona Stanley Hospital, Murdoch, Western Australia, Australia 11 School of Medicine and Pharmacology, The University of Western Australia, Crawley, Western Australia, Australia 12 School of Pathology and Laboratory Medicine, The University of Western Australia, Crawley, Western Australia, Australia Correspondence to: Elin Gray, email: // Keywords : melanoma, ctDNA, acquired resistance, MAPK inhibition, immunotherapy Received : August 03, 2015 Accepted : August 31, 2015 Published : September 22, 2015 Abstract Repeat tumor biopsies to study genomic changes during therapy are difficult, invasive and data are confounded by tumoral heterogeneity. The analysis of circulating tumor DNA (ctDNA) can provide a non-invasive approach to assess prognosis and the genetic evolution of tumors in response to therapy. Mutation-specific droplet digital PCR was used to measure plasma concentrations of oncogenic BRAF and NRAS variants in 48 patients with advanced metastatic melanoma prior to treatment with targeted therapies (vemurafenib, dabrafenib or dabrafenib/trametinib combination) or immunotherapies (ipilimumab, nivolumab or pembrolizumab). Baseline ctDNA levels were evaluated relative to treatment response and progression-free survival (PFS). Tumor-associated ctDNA was detected in the plasma of 35/48 (73%) patients prior to treatment and lower ctDNA levels at this time point were significantly associated with response to treatment and prolonged PFS, irrespective of therapy type. Levels of ctDNA decreased significantly in patients treated with MAPK inhibitors ( p < 0.001) in accordance with response to therapy, but this was not apparent in patients receiving immunotherapies. We show that circulating NRAS mutations, known to confer resistance to BRAF inhibitors, were detected in 3 of 7 (43%) patients progressing on kinase inhibitor therapy. Significantly, ctDNA rebound and circulating mutant NRAS preceded radiological detection of progressive disease. Our data demonstrate that ctDNA is a useful biomarker of response to kinase inhibitor therapy and can be used to monitor tumor evolution and detect the early appearance of resistance effectors.