459 research outputs found

    Evolutionary Divergence in Brain Size between Migratory and Resident Birds

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    Despite important recent progress in our understanding of brain evolution, controversy remains regarding the evolutionary forces that have driven its enormous diversification in size. Here, we report that in passerine birds, migratory species tend to have brains that are substantially smaller (relative to body size) than those of resident species, confirming and generalizing previous studies. Phylogenetic reconstructions based on Bayesian Markov chain methods suggest an evolutionary scenario in which some large brained tropical passerines that invaded more seasonal regions evolved migratory behavior and migration itself selected for smaller brain size. Selection for smaller brains in migratory birds may arise from the energetic and developmental costs associated with a highly mobile life cycle, a possibility that is supported by a path analysis. Nevertheless, an important fraction (over 68%) of the correlation between brain mass and migratory distance comes from a direct effect of migration on brain size, perhaps reflecting costs associated with cognitive functions that have become less necessary in migratory species. Overall, our results highlight the importance of retrospective analyses in identifying selective pressures that have shaped brain evolution, and indicate that when it comes to the brain, larger is not always better

    PNF 2.0? Initial evidence that gamification can increase the efficacy of brief, web-based personalized normative feedback alcohol interventions

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    Gamified interventions exploit the motivational characteristics of a game in order to provide prevention information and promote behavior change. Despite the modest effect sizes observed in increasingly popular web-based personalized normative feedback (PNF) alcohol interventions for college students, previous research has yet to consider how gamification might be used to enhance efficacy. This study examines whether a novel, gamified PNF intervention format, which includes a point-based reward system, the element of chance, and personal icons to visually represent users, is more effective in reducing short-term alcohol use than the standard web-based style of PNF currently used on college campuses. Two-hundred and thirty-seven college students were randomly assigned to receive either a standard brief, web-based PNF alcohol intervention or the same alcohol intervention components delivered within a Facebook-connected social game called CampusGANDR (Gamified Alcohol Norm Discovery and Readjustment). In both study conditions participants answered identical questions about their perceptions of peer drinking norms and own drinking and then received the same PNF slides. Two weeks following PNF delivery, participants again reported their perceptions of peers\u27 alcohol use and own drinking. Students in the CampusGANDR condition reported significantly reduced peer drinking norms and alcohol use at the two-week follow-up relative to students who received identical PNF delivered by standard online survey. Further, a mediation model demonstrated that this effect was driven by larger reductions in perceived drinking norms among participants assigned to receive CampusGANDR, relative to control. As web-based PNF is becoming an increasingly universal prevention strategy, findings from this study suggest gamification may represent one method by which intervention efficacy could be substantially improved. The potential methodological and economic benefits associated with gamified PNF interventions are emphasized and directions for future research are discussed

    Risk Assessment and Comparative Effectiveness of Left Ventricular Assist Device and Medical Management in Ambulatory Heart Failure Patients The ROADMAP Study 2-Year Results

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    OBJECTIVES The authors sought to provide the pre-specified primary endpoint of the ROADMAP (Risk Assessment and Comparative Effectiveness of Left Ventricular Assist Device and Medical Management in Ambulatory Heart Failure Patients) trial at 2 years. BACKGROUND The ROADMAP trial was a prospective nonrandomized observational study of 200 patients (97 with a left ventricular assist device [LVAD], 103 on optimal medical management [OMM]) that showed that survival with improved functional status at 1 year was better with LVADs compared with OMM in a patient population of ambulatory New York Heart Association functional class IIIb/IV patients. METHODS The primary composite endpoint was survival on original therapy with improvement in 6-min walk distance \u3e= 75 m. RESULTS Patients receiving LVAD versus OMM had lower baseline health-related quality of life, reduced Seattle Heart Failure Model 1-year survival (78% vs. 84%; p = 0.012), and were predominantly INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) profile 4 (65% vs. 34%; p \u3c 0.001) versus profiles 5 to 7. More LVAD patients met the primary endpoint at 2 years: 30% LVAD versus 12% OMM (odds ratio: 3.2 [95% confidence interval: 1.3 to 7.7]; p = 0.012). Survival as treated on original therapy at 2 years was greater for LVAD versus OMM (70 +/- 5% vs. 41 +/- 5%; p \u3c 0.001), but there was no difference in intent-to-treat survival (70 +/- 5% vs. 63 +/- 5%; p = 0.307). In the OMM arm, 23 of 103 (22%) received delayed LVADs (18 within 12 months; 5 from 12 to 24 months). LVAD adverse events declined after year 1 for bleeding (primarily gastrointestinal) and arrhythmias. CONCLUSIONS Survival on original therapy with improvement in 6-min walk distance was superior with LVAD compared with OMM at 2 years. Reduction in key adverse events beyond 1 year was observed in the LVAD group. The ROADMAP trial provides risk-benefit information to guide patient- and physician-shared decision making for elective LVAD therapy as a treatment for heart failure. (Risk Assessment and Comparative Effectiveness of Left Ventricular Assist Device and Medical Management in Ambulatory Heart Failure Patients [ROADMAP]; NCT01452802

    Resolving the Stellar Populations in a z=4 Lensed Galaxy

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    We present deep near-infrared Keck/NIRC imaging of a recently-discovered z=4.04 galaxy (Frye & Broadhurst 1998). This is lensed by the rich foreground cluster Abell~2390 (z~0.23) into highly-magnified arcs 3-5arcsec in length. Our H- and K'-band NIRC imaging allows us to map the Balmer+4000Ang break amplitude. In combination with high-quality archival HST/WFPC2 data, we can spatially resolve stellar populations along the arcs. The WFPC2 images clearly reveal several bright knots, which correspond to sites of active star formation. However, there are considerable portions of the arcs are significantly redder, consistent with being observed >100Myr after star formation has ceased. Keck/LRIS long-slit spectroscopy along the arcs reveals that the Ly-alpha emission is spatially offset by ~1arcsec from the rest-UV continuum regions. We show that this line emission is most probably powered by star formation in neighboring HII regions, and that the z=4 system is unlikely to be an AGN.Comment: Accepted for publication in the Astrophysical Journal. Uses emulateapj.sty and graphics.sty (included). 34 pages - has 5 tables and 21 encapsulated postscript figures, 4 in colour mail (B&W versions also provided

    A universal polymer shell-isolated nanoparticle (SHIN) design for single particle spectro-electrochemical SERS sensing using different core shapes

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    Shell-isolated nanoparticles (SHINs) have attracted increasing interest for non-interfering plasmonic enhanced sensing in fields such as materials science, biosensing, and in various electrochemical systems. The metallic core of these nanoparticles is isolated from the surrounding environment preventing direct contact or chemical interaction with the metal surface, while still being close enough to enable localized surface plasmon enhancement of the Raman scattering signal from the analyte. This concept forms the basis of the shell isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) technique. To date, the vast majority of SHIN designs have focused on SiO 2shells around spherical nanoparticle cores and there has been very limited published research considering alternatives. In this article, we introduce a new polymer-based approach which provides excellent control over the layer thickness and can be applied to plasmonic metal nanoparticles of various shapes and sizes without compromising the overall nanoparticle morphology. The SHIN layers are shown to exhibit excellent passivation properties and robustness in the case of gold nanosphere (AuNP) and anisotropic gold nanostar (AuNS) core shapes. In addition,in situSHINERS spectro-electrochemistry measurements performed on both SHIN and bare Au nanoparticles demonstrate the utility of the SHIN coatings. Correlated confocal Raman and SEM mapping was achieved to clearly establish single nanoparticle SERS sensitivity. Finally, confocalin situSERS mapping enabled visualisation of the redox related molecular structure changes occurring on an electrode surface in the vicinity of individual SHIN-coated nanoparticles

    Longitudinal Cognitive Performance of Alzheimer\u27s Disease Neuropathological Subtypes

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    Introduction: Alzheimer\u27s disease (AD) neuropathological subtypes (limbic predominant [lpAD], hippocampal sparing [HpSpAD], and typical [tAD]), defined by relative neurofibrillary tangle (NFT) burden in limbic and cortical regions, have not been studied in prospectively characterized epidemiological cohorts with robust cognitive assessments. Methods: Two hundred ninety-two participants with neuropathologically confirmed AD from the Religious Orders Study and Memory and Aging Project were categorized by neuropathological subtype based on previously specified diagnostic criteria using quantitative regional NFT counts. Rates of cognitive decline were compared across subtypes using linear mixed-effects models that included subtype, time, and a subtype-time interaction as predictors and four cognitive domain factor scores (memory, executive function, language, visuospatial) and a global score as outcomes. To assess if memory was relatively preserved in HpSpAD, non-memory factor scores were included as covariates in the mixed-effects model with memory as the outcome. Results: There were 57 (20%) with lpAD, 22 (8%) with HpSpAD and 213 (73%) with tAD. LpAD died significantly later than the participants with tAD (2.4 years, P = .01) and with HpSpAD (3.8 years, P = .03). Compared to tAD, HpSpAD, but not lpAD, performed significantly worse in all cognitive domains at the time of initial impairment and declined significantly faster in memory, language, and globally. HpSpAD did not have relatively preserved memory performance at any time point. Conclusion: The relative frequencies of AD neuropathological subtypes in an epidemiological sample were consistent with a previous report in a convenience sample. People with HpSpAD decline rapidly, but may not have a memory-sparing clinical syndrome. Cohort-specific differences in regional tau burden and comorbid neuropathology may explain the lack of clinicopathological correlation

    Discovery of a massive giant planet with extreme density around a sub-giant star TOI-4603

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    We present the discovery of a transiting massive giant planet around TOI-4603, a sub-giant F-type star from NASA's Transiting Exoplanet Survey Satellite (TESS). The newly discovered planet has a radius of 1.0420.035+0.0381.042^{+0.038}_{-0.035} RJR_{J}, and an orbital period of 7.245990.00021+0.000227.24599^{+0.00022}_{-0.00021} days. Using radial velocity measurements with the PARAS {and TRES} spectrographs, we determined the planet's mass to be 12.890.57+0.5812.89^{+0.58}_{-0.57} MJM_{J}, resulting in a bulk density of 14.11.6+1.714.1^{+1.7}_{-1.6} g cm3{cm^{-3}}. This makes it one of the few massive giant planets with extreme density and lies in the transition mass region of massive giant planets and low-mass brown dwarfs, an important addition to the population of less than five objects in this mass range. The eccentricity of 0.325±0.0200.325\pm0.020 and an orbital separation of 0.0888±0.00100.0888\pm0.0010 AU from its host star suggest that the planet is likely undergoing high eccentricity tidal (HET) migration. We find a fraction of heavy elements of 0.130.06+0.050.13^{+0.05}_{-0.06} and metal enrichment of the planet (ZP/ZstarZ_{P}/Z_{star}) of 4.22.0+1.64.2^{+1.6}_{-2.0}. Detection of such systems will offer us to gain valuable insights into the governing mechanisms of massive planets and improve our understanding of their dominant formation and migration mechanisms.Comment: accepted for publication in A&A Letter

    The Role of Pathological Aging in Cardiac and Pulmonary Fibrosis

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    Aging promotes a range of degenerative pathologies characterized by progressive losses of tissue and/or cellular function. Fibrosis is the hardening, overgrowth and scarring of various tissues characterized by the accumulation of extracellular matrix components. Aging is an important predisposing factor common for fibrotic heart and respiratory disease. Age-related processes such as senescence, inflammaging, autophagy and mitochondrial dysfunction are interconnected biological processes that diminish the regenerative capacity of the aged heart and lung and have been shown to play a crucial role in cardiac fibrosis and idiopathic pulmonary fibrosis. This review focuses on these four processes of aging in relation to their role in fibrosis. It has long been established that the heart and lung are linked both functionally and anatomically when it comes to health and disease, with an ever-expanding aging population, the incidence of fibrotic disease and therefore the number of fibrosis-related deaths will continue to rise. There are currently no feasible therapies to treat the effects of chronic fibrosis therefore highlighting the importance of exploring the processes of aging and its role in inducing and exacerbating fibrosis of each organ. The focus of this review may help to highlight potential avenues of therapeutic exploration</p

    Superhydrophilic Functionalization of Microfiltration Ceramic Membranes Enables Separation of Hydrocarbons from Frac and Produced Water

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    The environmental impact of shale oil and gas production by hydraulic fracturing (fracking) is of increasing concern. The biggest potential source of environmental contamination is flowback and produced water, which is highly contaminated with hydrocarbons, bacteria and particulates, meaning that traditional membranes are readily fouled. We show the chemical functionalisation of alumina ceramic microfiltration membranes (0.22 μm pore size) with cysteic acid creates a superhydrophilic surface, allowing for separation of hydrocarbons from frac and produced waters without fouling. The single pass rejection coefficients was >90% for all samples. The separation of hydrocarbons from water when the former have hydrodynamic diameters smaller than the pore size of the membrane is due to the zwitter ionically charged superhydrophilic pore surface. Membrane fouling is essentially eliminated, while a specific flux is obtained at a lower pressure (<2 bar) than that required achieving the same flux for the untreated membrane (4–8 bar)
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