1,156 research outputs found
Percentage of High Schoolers\u27 with Daily Soda Consumption by State Compared to the Percentage of High Schoolers with Obesity by State
We will be presenting a poster on the percentage of high schoolers\u27 with daily soda consumption by state compared to the percentage of high schoolers with obesity by state
Buoyancy Instabilities in Galaxy Clusters: Convection Due to Adiabatic Cosmic Rays and Anisotropic Thermal Conduction
Using a linear stability analysis and two and three-dimensional nonlinear
simulations, we study the physics of buoyancy instabilities in a combined
thermal and relativistic (cosmic ray) plasma, motivated by the application to
clusters of galaxies. We argue that cosmic ray diffusion is likely to be slow
compared to the buoyancy time on large length scales, so that cosmic rays are
effectively adiabatic. If the cosmic ray pressure is of
the thermal pressure, and the cosmic ray entropy (;
is the thermal plasma density) decreases outwards, cosmic rays drive an
adiabatic convective instability analogous to Schwarzschild convection in
stars. Global simulations of galaxy cluster cores show that this instability
saturates by reducing the cosmic ray entropy gradient and driving efficient
convection and turbulent mixing. At larger radii in cluster cores, the thermal
plasma is unstable to the heat flux-driven buoyancy instability (HBI), a
convective instability generated by anisotropic thermal conduction and a
background conductive heat flux. Cosmic-ray driven convection and the HBI may
contribute to redistributing metals produced by Type 1a supernovae in clusters.
Our calculations demonstrate that adiabatic simulations of galaxy clusters can
artificially suppress the mixing of thermal and relativistic plasma;
anisotropic thermal conduction allows more efficient mixing, which may
contribute to cosmic rays being distributed throughout the cluster volume.Comment: submitted to ApJ; 15 pages and 12 figures; abstract shortened to < 24
lines; for high resolution movies see
http://astro.berkeley.edu/~psharma/clustermovie.htm
Recommended from our members
Food geographies I: relational foodscapes and the busy-ness of being more-than-food
The study of foodscapes has spread throughout geography at the same time as food scholarship has spearheaded post-disciplinary research. This report argues that geographers have taken to post-disciplinarity to explore the ways that food is âmore-than-foodâ through analyses of the visceral nature of eating and politics and the vital (re)materializations of foodâs cultural geographies. Visceral food geographies illuminate what I call the âcontingent relationalitiesâ of food in the critical evaluation of the indeterminate, situated politics of âfeeling foodâ and those of the embodied collectivities of obesity. Questions remain, however, about how a visceral framework might be deployed for broader critiques within foodscapes and the study of human geography. The study of foodâs vital materialisms opens up investigation into the practices of the âmakingsâ of meat, food waste and eating networks. Analysis of affect, embodiment and cultural practices is central to these theorizations and suggests consideration of the multiple materialisms of food, space and eating. There is, I contend, in the more radical, âpost-relationalâ approaches to food, the need for a note of caution. Exuberant claims for the ontological, vital agency of food should be tempered by, or at least run parallel to, critical questions of the real politik of political and practical agency in light of recent struggles over austerity, food poverty and food justice
Coping with the effects of fear of failure in young elite athletes
Coping with stress is an important element in effective functioning at the elite level in sports, and fear of failure (FF) is an example of a stressor that athletes experience. Three issues underpin the present preliminary study. First, the prevalence of problems attributed to FF in achievement settings. Second, sport is a popular and significant achievement domain for children and adolescents. Third, there is a lack of research on FF in sport among this population. Therefore, the objectives of the study were to examine the effects of FF on young athletes and to find out their coping responses to the effects of FF. Interviews were conducted individually with nine young elite athÂletes (5 males, 4 females; ages 14-17 years). It was inferred from the data that FF affected the athletes' well-being, interpersonal behavior, sport performance, and schoolwork. The athletes employed a combination of problem-focused, emotion-foÂcused, and avoidance-focused coping strategies, with avoidance strategies being the most frequently reported
MIUSCAT: extended MILES spectral coverage. I. Stellar populations synthesis models
We extend the spectral range of our stellar population synthesis models based
on the MILES and CaT empirical stellar spectral libraries. For this purpose we
combine these two libraries with the Indo-U.S. to construct composite stellar
spectra to feed our models. The spectral energy distributions (SEDs) computed
with these models and the originally published models are combined to construct
composite SEDs for single-age, single-metallicity stellar populations (SSPs)
covering the range 3465 - 9469\AA at moderately high, and uniform, resolution
(FWHM=2.51\AA). The colours derived from these SSP SEDs provide good fits to
Galactic globular cluster data. We find that the colours involving redder
filters are very sensitive to the IMF, as well as a number of features and
molecular bands throughout the spectra. To illustrate the potential use of
these models we focus on the NaI doublet at 8200 \AA and with the aid of the
newly synthesized SSP model SEDs we define a new IMF-sensitive index that is
based on this feature, which overcomes various limitations from previous index
definitions for low velocity dispersion stellar systems. We propose an
index-index diagram based on this feature and the neighboring CaII triplet at
8600 \AA, to constrain the IMF if the age and [Na/Fe] abundance are known.
Finally we also show a survey-oriented spectrophotometric application which
evidences the accurate flux calibration of these models for carrying out
reliable spectral fitting techniques. These models are available through our
user-friendly website.Comment: 16 pages, 17 figures, 2 tables; MNRAS in press. Model predictions
available at our website: http://miles.iac.e
Intensity Mapping of Lyman-alpha Emission During the Epoch of Reionization
We calculate the absolute intensity and anisotropies of the Lyman-alpha
radiation field present during the epoch of reionization. We consider emission
from both galaxies and the intergalactic medium (IGM) and take into account the
main contributions to the production of Lyman-alpha photons: recombinations,
collisions, continuum emission from galaxies and scattering of Lyman-n photons
in the IGM. We find that the emission from individual galaxies dominates over
the IGM with a total Lyman-alpha intensity (times frequency) of about
(1.43-3.57)x10^{-8} erg s^{-1} cm^{-2} sr^{-1} at a redshift of 7. This
intensity level is low so it is unlikely that the Lyman-\alpha background
during reionization can be established by an experiment aiming at an absolute
background light measurement. Instead we consider Lyman-\alpha intensity
mapping with the aim of measuring the anisotropy power spectrum which has rms
fluctuations at the level of 1 x 10^{-16} [erg s^[-1} cm^{-2} sr^{-1}]^2 at a
few Mpc scales. These anisotropies could be measured with a spectrometer at
near-IR wavelengths from 0.9 to 1.4 \mu m with fields in the order of 0.5 to 1
sq. degrees. We recommend that existing ground-based programs using narrow band
filters also pursue intensity fluctuations to study statistics on the spatial
distribution of faint Lyman-\alpha emitters. We also discuss the
cross-correlation signal with 21 cm experiments that probe HI in the IGM during
reionization. A dedicated sub-orbital or space-based Lyman-\alpha intensity
mapping experiment could provide a viable complimentary approach to probe
reionization, when compared to 21 cm experiments, and is likely within
experimental reach.Comment: 18 pages, 17 figure
MIUSCAT: extended MILES spectral coverage. II. Constraints from optical photometry
In the present work we show a comprehensive comparison of our new stellar
population synthesis MIUSCAT models with photometric data of globular clusters
and early-type galaxies. The models compare remarkably well with the colours of
Milky Way globular clusters in the optical range. Likewise, the colours of M31
globular clusters can also be explained by the models by assuming younger ages
then their Galactic counterparts. When compared with quiescent galaxies we
reproduce the colour evolution at intermediate redshift. On the other hand we
find that the colour relations of nearby early-type galaxies are still a
challenge for present-day stellar population synthesis models. We investigate a
number of possible explanations and establish the importance of alpha-enhanced
models to bring down the discrepancy with observations.Comment: 20 pages, 17 figures; MNRAS in press. Model predictions available at
our website: http://miles.iac.e
The merger that led to the formation of the Milky Way's inner stellar halo and thick disk
The assembly process of our Galaxy can be retrieved using the motions and
chemistry of individual stars. Chemo-dynamical studies of the nearby halo have
long hinted at the presence of multiple components such as streams, clumps,
duality and correlations between the stars' chemical abundances and orbital
parameters. More recently, the analysis of two large stellar surveys have
revealed the presence of a well-populated chemical elemental abundance
sequence, of two distinct sequences in the colour-magnitude diagram, and of a
prominent slightly retrograde kinematic structure all in the nearby halo, which
may trace an important accretion event experienced by the Galaxy. Here report
an analysis of the kinematics, chemistry, age and spatial distribution of stars
in a relatively large volume around the Sun that are mainly linked to two major
Galactic components, the thick disk and the stellar halo. We demonstrate that
the inner halo is dominated by debris from an object which at infall was
slightly more massive than the Small Magellanic Cloud, and which we refer to as
Gaia-Enceladus. The stars originating in Gaia-Enceladus cover nearly the full
sky, their motions reveal the presence of streams and slightly retrograde and
elongated trajectories. Hundreds of RR Lyrae stars and thirteen globular
clusters following a consistent age-metallicity relation can be associated to
Gaia-Enceladus on the basis of their orbits. With an estimated 4:1 mass-ratio,
the merger with Gaia-Enceladus must have led to the dynamical heating of the
precursor of the Galactic thick disk and therefore contributed to the formation
of this component approximately 10 Gyr ago. These findings are in line with
simulations of galaxy formation, which predict that the inner stellar halo
should be dominated by debris from just a few massive progenitors.Comment: 19 pages, 8 figures. Published in Nature in the issue of Nov. 1st,
2018. This is the authors' version before final edit
Fine-mapping identifies multiple prostate cancer risk loci at 5p15, one of which associates with TERT expression
Associations between single nucleotide polymorphisms (SNPs) at 5p15 and multiple cancer types have been reported. We have previously shown evidence for a strong association between prostate cancer (PrCa) risk and rs2242652 at 5p15, intronic in the telomerase reverse transcriptase (TERT) gene that encodes TERT. To comprehensively evaluate the association between genetic variation across this region and PrCa, we performed a fine-mapping analysis by genotyping 134 SNPs using a custom Illumina iSelect array or Sequenom MassArray iPlex, followed by imputation of 1094 SNPs in 22 301 PrCa cases and 22 320 controls in The PRACTICAL consortium. Multiple stepwise logistic regression analysis identified four signals in the promoter or intronic regions of TERT that independently associated with PrCa risk. Gene expression analysis of normal prostate tissue showed evidence that SNPs within one of these regions also associated with TERT expression, providing a potential mechanism for predisposition to disease
Emotional and affective geographies of sustainable community leadership: A visceral approach
In this paper, we aim to better understand what mobilises people into being and becoming named as leaders in sustainability in the places where they live. Our premise is that action for sustainability originates with passionate individuals who lead action at the local level. We present our analysis of a walking sensory ethnography conducted in 2012 undertaken as part of exploratory research on adaptation to climate change in the coastal town of Dunbar, Scotland. We sought to understand the complex, embodied and sensorial ways in which places, and our experiences of connection to places, are constituted. The starting point for our discussion is the recognition of the intricate, deeply entangled relations between the human and nonhuman world that have historically been obscured by western understandings of a pristine nature set apart from the world of human culture. Building on literature under the umbrella of âAnthropocene feminismsâ, we suggest that a visceral approach as conceptualised in the work of Hayes-Conroy and Hayes-Conroy (2008) and Hayes-Conroy and Martin (2010) offers embodied knowledge as a radically relational view of the world that allows an entry into the ways in which the micro-scale of the body intersects with the global scale of political praxis. Our detailed discussion of one of our research participants provides an example as to how this individual came to feel connected through a shared sense of consciousness with the human and non-human. In this exploration, we found possibilities in thinking beyond the otherwise paralysing narratives of anthropogenic climate change. Our argument is that this focus brings to the fore the transformative capacity of viscera, emotional and affective responses to anthropogenic climate change, and that these are integral to hope, albeit this is a hope that needs to consider capacity and vulnerability in new ways
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