687 research outputs found
A statistical method for measuring the Galactic potential and testing gravity with cold tidal streams
We introduce the Minimum Entropy Method, a simple statistical technique for
constraining the Milky Way gravitational potential and simultaneously testing
different gravity theories directly from 6D phase-space surveys and without
adopting dynamical models. We demonstrate that orbital energy distributions
that are separable (i.e. independent of position) have an associated entropy
that increases under wrong assumptions about the gravitational potential and/or
gravity theory. Of known objects, `cold' tidal streams from low-mass
progenitors follow orbital distributions that most nearly satisfy the condition
of separability. Although the orbits of tidally stripped stars are perturbed by
the progenitor's self-gravity, systematic variations of the energy distribution
can be quantified in terms of the cross-entropy of individual tails, giving
further sensitivity to theoretical biases in the host potential. The
feasibility of using the Minimum Entropy Method to test a wide range of gravity
theories is illustrated by evolving restricted N-body models in a Newtonian
potential and examining the changes in entropy introduced by Dirac, MONDian and
f(R) gravity modifications.Comment: Accepted for publication in ApJ. 11 pages 6 figure
CAMERA: a compact, automated, laser adaptive optics system for small aperture telescopes
CAMERA is an autonomous laser guide star adaptive optics system designed for small aperture telescopes. This system is intended to be mounted permanently on such a telescope to provide large amounts of flexibly scheduled observing time, delivering high angular resolution imagery in the visible and near infrared. The design employs a Shack Hartmann wavefront sensor, a 12x12 actuator MEMS device for high order wavefront compensation, and a solid state 355nm ND:YAG laser to generate a guide star. Commercial CCD and InGaAs detectors provide coverage in the visible and near infrared. CAMERA operates by selecting targets from a queue populated by users and executing these observations autonomously. This robotic system is targeted towards applications that are diffcult to address using classical observing strategies: surveys of very large target lists, recurrently scheduled observations, and rapid response followup of transient objects. This system has been designed and costed, and a lab testbed has been developed to evaluate key components and validate autonomous operations
Mixed policies give more options in multifunctional tropical forest landscapes
This archive stores data utilised in: Mixed policies give more options in multifunctional tropical forest landscapesLaw E.A., Bryan B.A., Meijaard E., Mallawaarachchi T., Struebig M.J., Watts M., Wilson K.A.Journal of Applied Ecology 2016Corresponding author:Elizabeth A. Law*The University of Queensland, School of Biological [email protected]: Jan 18, 2016----------------------DETAILS:Along with this txt file, this archive contains five csv files included, and one folder containing a shape file. These are in the typical format required for input into Marxan with Zones, available from http://www.uq.edu.au/marxan/ (also see new cloud development on Marxan.net). The data time frames relate to a start year of 2008 (see associated publication for further details.Readme.txt - this documentZones.csv - contains zone identification numbers (zoneid) and names (zonenames)FeatureTargets.csv - contains feature id (id), the targets (target; units are specified in supplementary material), species penalty factor (spf; weighting number to determine if the feature is considered as an optimisation threshold constraint, 1, or not, 0), and feature names (name; features 1-9 and 19-20 represent primate species, 10-14 forest types, and 15-17 production values smallholder agriculture, timber, and oil palm, and 18 carbon emissions reduction.Extant.csv - contains planning unit id (pu), the extant class (class; using descriptive codes), and the area (area.ha, in hectares).PuVsFeatures.csv - for every planning unit and feature combination, the 'amount' gives the maximum possible achievement for that feature in that planning unit. Units of measurement are indicated in the main text/supplementary methods and associated papers detailing data development.BaselineZoneContributions.csv - for every zone, planning unit, and feature combination (identified using zoneid, puid, featid codes found in their respective files), this gives the fraction of the full amount possible to achieve within that pu for that feature. Pulayer folder - contains a shape file created in arcgis for the planning units. Coordinate reference system is WGS 84 / UTM zone 49S. One column in the attribute table, indicating the planning unit number (pu)
limma powers differential expression analyses for RNA-sequencing and microarray studies
limma is an R/Bioconductor software package that provides an integrated solution for analysing data from gene expression experiments. It contains rich features for handling complex experimental designs and for information borrowing to overcome the problem of small sample sizes. Over the past decade, limma has been a popular choice for gene discovery through differential expression analyses of microarray and high-throughput PCR data. The package contains particularly strong facilities for reading, normalizing and exploring such data. Recently, the capabilities of limma have been significantly expanded in two important directions. First, the package can now perform both differential expression and differential splicing analyses of RNA sequencing (RNA-seq) data. All the downstream analysis tools previously restricted to microarray data are now available for RNA-seq as well. These capabilities allow users to analyse both RNA-seq and microarray data with very similar pipelines. Second, the package is now able to go past the traditional gene-wise expression analyses in a variety of ways, analysing expression profiles in terms of co-regulated sets of genes or in terms of higher-order expression signatures. This provides enhanced possibilities for biological interpretation of gene expression differences. This article reviews the philosophy and design of the limma package, summarizing both new and historical features, with an emphasis on recent enhancements and features that have not been previously describe
Manifestations of Overarousal Account For the Association Between Cognitive Anxiety Sensitivity and Suicidal Ideation
Background: Recent evidence suggests an association between cognitive anxiety sensitivity and suicidal ideation. Cognitive anxiety sensitivity has also been implicated as a precursor to various forms of overarousal. These manifestations of overarousal (i.e., agitation, insomnia, nightmares, and anger) may account for the association between cognitive anxiety sensitivity and suicidal ideation.
Methods: In Study 1, undergraduate students selectively sampled for recent suicidal ideation completed all measures online. In Study 2, clinical outpatients completed all measures prior to their initial intake appointments at a psychology clinic.
Results: Study 1 demonstrated that agitation and insomnia individually and jointly accounted for the association between cognitive anxiety sensitivity and suicidal ideation, controlling for general anxiety and demographic variables. Study 2 replicated and extended these findings, such that, controlling for demographics, general anxiety, and physical and social anxiety sensitivity, agitation and anger each independently and together accounted for the association between cognitive anxiety sensitivity and suicidal ideation, whereas insomnia and nightmares did not.
Limitations: This study utilized a cross-sectional design and self-report measures in both samples as well as a sample of undergraduate students in Study 1.
Conclusions: Together, these findings suggest that agitation and anger may explain the previously established relationship between cognitive anxiety sensitivity and suicidal ideation. Targeting cognitive anxiety sensitivity in treatment may in turn reduce these forms of overarousal and thereby suicide risk
Impact of Age and Estimated Glomerular Filtration Rate on the Glycemic Efficacy and Safety of Canagliflozin: A Pooled Analysis of Clinical Studies.
AbstractObjectiveReduced efficacy has been reported in the elderly; it may be a consequence of an age-dependent decline in estimated glomerular filtration rate (eGFR) rather than ageing per se. We sought to determine the impact of these 2 parameters, as well as sex and baseline body mass index (BMI), on the efficacy and safety of canagliflozin, a sodium glucose co-transporter 2 inhibitor, in people with type 2 diabetes.MethodsData were pooled from 6 randomized, double-blind, placebo-controlled studies (18 or 26 weeks; N=4053). Changes in glycated hemoglobin (A1C) and systolic blood pressure (BP) from baseline with canagliflozin 100āmg and 300āmg and placebo were evaluated in subgroups by sex, baseline BMI, baseline age and baseline eGFR. Safety was assessed by reports of adverse events.ResultsPlacebo-subtracted reductions in A1C with canagliflozin 100āmg and 300āmg were similar in men and women. A1C reductions with canagliflozin were seen across BMI subgroups and in participants aged <65 years and ā„65 years. Significantly greater placebo-subtracted reductions in A1C were seen with both canagliflozin doses in participants with higher baseline eGFR (ā„90āmL/min/1.73ām2). Reductions in systolic BP were seen with canagliflozin across subgroups of sex, BMI, age and eGFR. A1C reductions with canagliflozin were similar for participants aged <65 or ā„65 years who had baseline eGFR ā„60āmL/min/1.73ām2 and were smaller in older than in younger participants with baseline eGFR 45 to <60āmL/min/1.73ām2. The overall incidence of adverse events was similar across treatment groups regardless of sex, baseline BMI, baseline age or baseline eGFR.ConclusionsCanagliflozin improved glycemic control, reduced BP and was generally well tolerated in people with type 2 diabetes across a range of ages, BMIs and renal functions
CAMERA: a compact, automated, laser adaptive optics system for small aperture telescopes
CAMERA is an autonomous laser guide star adaptive optics system designed for small aperture telescopes. This system is intended to be mounted permanently on such a telescope to provide large amounts of flexibly scheduled observing time, delivering high angular resolution imagery in the visible and near infrared. The design employs a Shack Hartmann wavefront sensor, a 12x12 actuator MEMS device for high order wavefront compensation, and a solid state 355nm ND:YAG laser to generate a guide star. Commercial CCD and InGaAs detectors provide coverage in the visible and near infrared. CAMERA operates by selecting targets from a queue populated by users and executing these observations autonomously. This robotic system is targeted towards applications that are diffcult to address using classical observing strategies: surveys of very large target lists, recurrently scheduled observations, and rapid response followup of transient objects. This system has been designed and costed, and a lab testbed has been developed to evaluate key components and validate autonomous operations
Does wage rank affect employees' well-being?
How do workers make wage comparisons? Both an experimental study and an analysis of 16,000 British employees are reported. Satisfaction and well-being levels are shown to depend on more than simple relative pay. They depend upon the ordinal rank of an individual's wage within a comparison group. āRankā itself thus seems to matter to human beings. Moreover, consistent with psychological theory, quits in a workplace are correlated with pay distribution skewness
Estimated mortality of adult HIV-infected patients starting treatment with combination antiretroviral therapy
To provide estimates of mortality among HIV-infected patients starting combination antiretroviral therapy
KELT-8b: A highly inflated transiting hot Jupiter and a new technique for extracting high-precision radial velocities from noisy spectra
We announce the discovery of a highly inflated transiting hot Jupiter
discovered by the KELT-North survey. A global analysis including constraints
from isochrones indicates that the V = 10.8 host star (HD 343246) is a mildly
evolved, G dwarf with K, , , an inferred mass
M, and radius
R. The planetary companion has mass , radius
, surface gravity , and density
g cm. The planet is on a roughly
circular orbit with semimajor axis AU and
eccentricity . The best-fit linear ephemeris is
BJD and
days. This planet is one of the most inflated of all known transiting
exoplanets, making it one of the few members of a class of extremely low
density, highly-irradiated gas giants. The low stellar and large
implied radius are supported by stellar density constraints from follow-up
light curves, plus an evolutionary and space motion analysis. We also develop a
new technique to extract high precision radial velocities from noisy spectra
that reduces the observing time needed to confirm transiting planet candidates.
This planet boasts deep transits of a bright star, a large inferred atmospheric
scale height, and a high equilibrium temperature of
K, assuming zero albedo and perfect heat redistribution, making it one of the
best targets for future atmospheric characterization studies.Comment: Submitted to ApJ, feedback is welcom
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