30 research outputs found

    Effect of local environment and stellar mass on galaxy quenching and morphology at 0.5<z<2.00.5<z<2.0

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    We study galactic star-formation activity as a function of environment and stellar mass over 0.5<z<2.0 using the FourStar Galaxy Evolution (ZFOURGE) survey. We estimate the galaxy environment using a Bayesian-motivated measure of the distance to the third nearest neighbor for galaxies to the stellar mass completeness of our survey, log(M/M)>9(9.5)\log(M/M_\odot)>9 (9.5) at z=1.3 (2.0). This method, when applied to a mock catalog with the photometric-redshift precision (σz/(1+z)0.02\sigma_z / (1+z) \lesssim 0.02), recovers galaxies in low- and high-density environments accurately. We quantify the environmental quenching efficiency, and show that at z> 0.5 it depends on galaxy stellar mass, demonstrating that the effects of quenching related to (stellar) mass and environment are not separable. In high-density environments, the mass and environmental quenching efficiencies are comparable for massive galaxies (log(M/M)\log (M/M_\odot)\gtrsim 10.5) at all redshifts. For lower mass galaxies (log(M/M))\log (M/M)_\odot) \lesssim 10), the environmental quenching efficiency is very low at zz\gtrsim 1.5, but increases rapidly with decreasing redshift. Environmental quenching can account for nearly all quiescent lower mass galaxies (log(M/M)\log(M/M_\odot) \sim 9-10), which appear primarily at zz\lesssim 1.0. The morphologies of lower mass quiescent galaxies are inconsistent with those expected of recently quenched star-forming galaxies. Some environmental process must transform the morphologies on similar timescales as the environmental quenching itself. The evolution of the environmental quenching favors models that combine gas starvation (as galaxies become satellites) with gas exhaustion through star-formation and outflows ("overconsumption"), and additional processes such as galaxy interactions, tidal stripping and disk fading to account for the morphological differences between the quiescent and star-forming galaxy populations.Comment: 29 pages, 15 figure, accepted for publication in Ap

    ZFOURGE/CANDELS: On the Evolution of \u3cem\u3eM\u3c/em\u3e* Galaxy Progenitors from \u3cem\u3ez\u3c/em\u3e=3 to 0.5*

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    Galaxies with stellar masses near M* contain the majority of stellar mass in the universe, and are therefore of special interest in the study of galaxy evolution. The Milky Way (MW) and Andromeda (M31) have present-day stellar masses near M*, at 5 × 1010 M ☉ (defined here to be MW-mass) and 1011 M ☉ (defined to be M31-mass). We study the typical progenitors of these galaxies using the FOURSTAR Galaxy Evolution Survey (ZFOURGE). ZFOURGE is a deep medium-band near-IR imaging survey, which is sensitive to the progenitors of these galaxies out to z ~ 3. We use abundance-matching techniques to identify the main progenitors of these galaxies at higher redshifts. We measure the evolution in the stellar mass, rest-frame colors, morphologies, far-IR luminosities, and star formation rates, combining our deep multiwavelength imaging with near-IR Hubble Space Telescope imaging from Cosmic Near-IR Deep Extragalactic Legacy Survey (CANDELS), and Spitzer and Herschel far-IR imaging from Great Observatories Origins Deep Survey-Herschel and CANDELS-Herschel. The typical MW-mass and M31-mass progenitors passed through the same evolution stages, evolving from blue, star-forming disk galaxies at the earliest stages to redder dust-obscured IR-luminous galaxies in intermediate stages and to red, more quiescent galaxies at their latest stages. The progenitors of the MW-mass galaxies reached each evolutionary stage at later times (lower redshifts) and with stellar masses that are a factor of two to three lower than the progenitors of the M31-mass galaxies. The process driving this evolution, including the suppression of star formation in present-day M* galaxies, requires an evolving stellar-mass/halo-mass ratio and/or evolving halo-mass threshold for quiescent galaxies. The effective size and SFRs imply that the baryonic cold-gas fractions drop as galaxies evolve from high redshift to z ~ 0 and are strongly anticorrelated with an increase in the Sérsic index. Therefore, the growth of galaxy bulges in M* galaxies corresponds to a rapid decline in the galaxy gas fractions and/or a decrease in the star formation efficiency

    The criminal justice voluntary sector: concepts and an agenda for an emerging field

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    This is the peer reviewed version of the following article: Tomczak, P. & Buck, G. (2019). The criminal justice voluntary sector: concepts and an agenda for an emerging field. Howard Journal of Crime and Justice, 58(3), which has been published in final form at https://doi.org/10.1111/hojo.12326. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.Volunteers and voluntary organisations play significant roles pervading criminal justice. They are key actors, with unrecognised potential to shore up criminal justice and/or collaboratively reshape social justice. Unlike public and for-profit agents, criminal justice volunteers and voluntary organisations (CJVVOs) have been neglected by scholars. We call for analyses of diverse CJVVOs, in national and comparative contexts. We provide three categories to highlight distinctive organising auspices, which hold across criminal justice: statutory volunteers, quasi-statutory volunteers and voluntary organisations. The unknown implications of these different forms of non-state, non-profit justice involvement deserve far greater attention from academics, policymakers and practitioners

    Eye trauma in children and adolescents in urgent and emergency medical services: a scoping review

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    Ocular trauma is defined as an injury to the eyeball that can be caused by mechanical, chemical, or thermal trauma. It is considered the most common cause of non-congenital blindness in children. It has serious short—and long-term consequences, such as impaired visual acuity, angular recession, and traumatic cataracts. For this reason, identifying in the world scientific literature the mechanisms of trauma, types of injury, risk factors, and initial management of ocular trauma in children and adolescents is of clinical relevance for greater knowledge on the subject. Furthermore, the information obtained in the literature can help prevent this type of injury and serious complications that can impact the patient's quality of life in the short and long term. Furthermore, preventive public health strategies must include patient education, family members, and adults close to the child and adolescent, such as teachers and physical educators, about eye health

    Moulage in high-fidelity simulation-A chest wall burn escharotomy model for visual realism and as an educational tool

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    Introduction: There is a paucity of literature pertaining to the role and techniques of moulage for creating high-fidelity medical simulations. As part of an Intensive Care Crisis Event Management Course, simulation of an extensive torso burn was desired. The aim of the moulage was to enhance the realism of the scenario but additionally to enable a chest wall escharotomy to be performed

    The S.T.A.B. Trial-Standardized testing of artificial blood: A comparative study of various products that may be used as artificial blood for high fidelity simulation training in the critical care setting

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    Aim: In the current climate of medical education, there is an ever-increasing demand for and emphasis on simulation as both a teaching and training tool. The objective of our study was to compare the realism and practicality of a number of artificial blood products that could be used for high-fidelity simulation. Method: A literature and internet search was performed and 15 artificial blood products were identified from a variety of sources. One product was excluded due to its potential toxicity risks. Five observers, blinded to the products, performed two assessments on each product using an evaluation tool with 14 predefined criteria including color, consistency, clotting, and staining potential to manikin skin and clothing. Each criterion was rated using a five-point Likert scale. The products were left for 24 hours, both refrigerated and at room temperature, and then reassessed. Statistical analysis was performed to identify the most suitable products, and both inter- and intra-rater variability were examined. Results: Three products scored consistently well with all five assessors, with one product in particular scoring well in almost every criterion. This highest-rated product had a mean rating of 3.6 of 5.0 (95% posterior Interval 3.4-3.7). Inter-rater variability was minor with average ratings varying from 3.0 to 3.4 between the highest and lowest scorer. Intrarater variability was negligible with good agreement between first and second rating as per weighted kappa scores (K = 0.67). Conclusion: The most realistic and practical form of artificial blood identified was a commercial product called KD151 Flowing Blood Syrup. It was found to be not only realistic in appearance but practical in terms of storage and stain removal

    Histopathological classification of precursor lesions of esophageal adenocarcinoma: A Deep Multiple Instance Learning Approach

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    In this paper, we hypothesize that morphological properties of nuclei are crucial for classifying dysplastic changes. Therefore, we propose to represent a whole histopathology slide as a collection of smaller images containing patches of nuclei and adjacent tissue. For this purpose, we use a deep multiple instance learning approach. Within this framework we first embed patches in a low-dimensional space using convolutional and fully-connected layers. Next, we combine the lowdimensional embeddings using a multiple instance learning pooling operator and eventually we use fully-connected layers to provide a classification. We evaluate our approach on esophagus cancer histopathology dataset
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