53 research outputs found

    LIFE HISTORY AND MORPHOMETRIC VARIATION OF GAMBUSIA NOBILIS AT BITTER LAKE NATIONAL WILDLIFE REFUGE

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    The Pecos Gambusia, Gambusia nobilis, is an endangered, live bearing fish inhabiting sinkholes in a restricted range of the Pecos River Watershed in New Mexico and Texas. The sink holes at Bitter Lake National Wildlife Refuge (BLNWR), Roswell, NM create isolated habitats with varying ecological conditions (habitat size, community composition, dissolved oxygen, salinity and pH). This ecological variation imposes unique selective pressures that may shape differences in life history characteristics and morphology between populations. The goals of this research were to characterize seasonal and population variation in 1) life history characteristics, 2) embryo development patterns, 3) morphology and 4) explore cursory relationships between ecological conditions and G. nobilis morphology and life history. Monthly sampling was conducted at BLNWR (May 2011 through April 2012) at sinkholes 7, 27 South, 31, and 37. A trade-off between egg size and brood size was observed from investment in many small embryos to fewer large offspring from April through August. Despite differences in ecological parameters, no significant differences in reproductive traits were observed between the populations. Interestingly, reproductive effort and average egg size were not correlated with female size. Larger females invested relatively the same amount into reproduction but invested in larger broods rather than increased average egg mass. An analysis of embryo developmental stages identified 1) asynchronous reproduction between females, 2) eggs in multiple stages of development within some gravid females (evidence for superfetation), and 3) increasing average egg mass of later developmental stages suggesting some element of matrotrophy (post-fertilization nutrient transfer). Geometric morphometric techniques were used to evaluate seasonal and population shape differences. During the reproductive season, females tended to be deeper bodied with a posteriorly shifted anal fin. Males and females from sinkhole 31 differed significantly from the other populations; they had deeper body profiles and shorter caudal peduncles than sinkholes 7, 27 South, and 37 which could be related to less predation and higher dissolved oxygen in sinkhole 31. Analyzing life history allocation strategies and identifying seasonal and population differences in morphology and reproduction contributes information that may be important in formulating management strategies and conservation plans for this endangered species

    Evolution of star formation in the UKIDSS ultra deep survey field-I. Luminosity functions and cosmic star formation rate out to z = 1.6

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    We present new results on the cosmic star formation history in the Subaru/XMM-Newton Deep Survey (SXDS)-Ultra Deep Survey (UDS) field out to z = 1.6. We compile narrowband data from the Subaru Telescope and the Visible and Infrared Survey Telescope forAstronomy (VISTA) in conjunction with broad-band data from the SXDS and UDS, to makea selection of 5725 emission-line galaxies in 12 redshift slices, spanning 10 Gyr of cosmictime. We determine photometric redshifts for the sample using 11-band photometry, and usea spectroscopically confirmed subset to fine tune the resultant redshift distribution. We usethe maximum-likelihood technique to determine luminosity functions in each redshift slice and model the selection effects inherent in any narrow-band selection statistically, to obviatethe retrospective corrections ordinarily required. The deep narrow-band data are sensitive tovery low star formation rates (SFRs), and allow an accurate evaluation of the faint end slopeof the Schechter function, α We find that a is particularly sensitive to the assumed faintest broad-band magnitude of a galaxy capable of hosting an emission line, and propose thatthis limit should be empirically motivated. For this analysis, we base our threshold on thelimiting observed equivalent widths of emission lines in the local Universe. We compute thecharacteristic SFR of galaxies in each redshift slice, and the integrated SFR density,ρ SFR. Wefind our results to be in good agreement with the literature and parametrize the evolution of the SFR density as ρ SFR α(1 + z)4.58 confirming a steep decline in star formation activity since z ~ 1.6.Peer reviewe

    Healthy Annapolis

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    Final project for Urban Studies and Planning Studio (Summer 2017). University of Maryland, College Park.Annapolis, Maryland, located in Anne Arundel County, is home to the United States Naval Academy and Saint John’s College. The small waterfront capital city is also a popular tourist destination for sailors and history buffs drawn to the nationally recognized historic district. While continuing to focus on preserving the City’s historic and natural resources and strong local economy, Annapolis is taking steps to become a healthier city by participating in the Let’s Move! Cities Towns, and Counties (LMCTC) initiative, a national campaign to end childhood obesity by providing guidance to elected officials, parents, schools, community leaders, and other stakeholders in order to make healthy living accessible for everyone. Annapolis has successfully met the five initial program goals for LMCTC, and has achieved All-Star status. This report will help the City pursue three of the four All-Star strategies it is now eligible to pursue after achieving All-Star status. This report highlights disadvantaged communities, as they are more likely to suffer from poor health. In addition to an increased likelihood of health issues, these communities are also less likely to have resources such as education and community support to improve certain aspects of their health. This University of Maryland PALS summer studio project is meant to help guide the City of Annapolis in creating a healthier city for all residents, and in reaching their LMCTC All-Star strategies. Four chapters were written by groups that focused on health-related aspects of the city that relate directly to areas of focus for achieving All-Star status: 1) updates to incorporate health into the Comprehensive Plan, 2) parks and open space, 3) bicycle infrastructure, and 4) urban agriculture and community gardens. We hope that by providing recommendations for integrating health into the planning process and city design, and by suggesting strategies to make the most effective use of existing tools, Annapolis will be better situated to achieve its LMCTC All-Star strategies.The City of Annapoli

    Recent smell loss is the best predictor of COVID-19 among individuals with recent respiratory symptoms

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    In a preregistered, cross-sectional study we investigated whether olfactory loss is a reliable predictor of COVID-19 using a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. Both C19+ and C19- groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both univariate and multivariate models (ROC AUC=0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0-10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≀2 indicate high odds of symptomatic COVID-19 (4<10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable

    The genetic architecture of the human cerebral cortex

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    The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    The genetic architecture of the human cerebral cortex

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    The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570
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