2,665 research outputs found

    Two-Particle Microrheology of quasi-2D Viscous Systems

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    We study the correlated motions of colloidal particles in a quasi-2D system (Human Serum Albumin (HSA) protein molecules at an air-water interface) for different surface viscosities ηs\eta_{s}. We observe a transition in the behavior of the correlated motion, from 2-D interface dominated at high ηs\eta_{s} to bulk fluid-dependent at low ηs\eta_{s}. The correlated motions can be scaled onto a master curve which captures the features of this transition. This master curve also characterizes the spatial dependence of the flow field of a viscous interface in response to a force. From the flow field and the correlated particle motions, we calculate a two-particle MSD (mean square displacement) for direct comparison with rheological measurements.Comment: 4 pages, 4 figures, submitted to PR

    Incorporating Acupuncture Into American Healthcare: Initiating a Discussion on Implementation Science, the Status of the Field, and Stakeholder Considerations

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    Introduction: The field of implementation science is the study of methods that promote the uptake of evidence-based interventions into healthcare policy and practice. While acupuncture has gained significant traction in the American healthcare landscape, its journey has been somewhat haphazard and non-linear. Methods: In June 2019, a group of thirty diverse stakeholders was convened by the Society for Acupuncture Research with the support of a Patient Centered Outcomes Research Institute, Eugene Washington Engagement Award. This group of stakeholders represented a diverse mix of patients, providers, academicians, researchers, funders, allied health professionals, insurers, association leaders, certification experts, and military program developers. The collective engaged in discussion that explored acupuncture\u27s status in healthcare, including reflections on its safety, effectiveness, best practices, and the actual implementation of acupuncture as seen from diverse stakeholder viewpoints. Objectives: A primary goal was to consider how to utilize knowledge from the field of implementation science more systematically and intentionally to disseminate information about acupuncture and its research base, through application of methods known to implementation science. The group also considered novel challenges that acupuncture may present to known implementation processes. Findings: This article summarizes the initial findings of this in-person meeting of stakeholders and the ongoing discussion among the subject matter experts who authored this report. The goal of this report is to catalyze greater conversation about how the field of implementation science might intersect with practice, access, research, and policymaking pertaining to acupuncture. Core concepts of implementation science and its relationship to acupuncture are introduced, and the case for acupuncture as an Evidence Based Practice (EBP) is established. The status of the field and current environment of acupuncture is examined, and the perspectives of four stakeholder groups--patients, two types of professional practitioners, and researchers--are explored in more detail

    Stretching and squeezing of sessile dielectric drops by the optical radiation pressure

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    We study numerically the deformation of sessile dielectric drops immersed in a second fluid when submitted to the optical radiation pressure of a continuous Gaussian laser wave. Both drop stretching and drop squeezing are investigated at steady state where capillary effects balance the optical radiation pressure. A boundary integral method is implemented to solve the axisymmetric Stokes flow in the two fluids. In the stretching case, we find that the drop shape goes from prolate to near-conical for increasing optical radiation pressure whatever the drop to beam radius ratio and the refractive index contrast between the two fluids. The semi-angle of the cone at equilibrium decreases with the drop to beam radius ratio and is weakly influenced by the index contrast. Above a threshold value of the radiation pressure, these "optical cones" become unstable and a disruption is observed. Conversely, when optically squeezed, the drop shifts from an oblate to a concave shape leading to the formation of a stable "optical torus". These findings extend the electrohydrodynamics approach of drop deformation to the much less investigated "optical domain" and reveal the openings offered by laser waves to actively manipulate droplets at the micrometer scale

    Temporal and spatial structure of multi‐millennial temperature changes at high latitudes during the Last Interglacial

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    The Last Interglacial (LIG, 129–116 thousand of years BP, ka) represents a test bed for climate model feedbacks in warmer-than-present high latitude regions. However, mainly because aligning different palaeoclimatic archives and from different parts of the world is not trivial, a spatio-temporal picture of LIG temperature changes is difficult to obtain. Here, we have selected 47 polar ice core and sub-polar marine sediment records and developed a strategy to align them onto the recent AICC2012 ice core chronology. We provide the first compilation of high-latitude temperature changes across the LIG associated with a coherent temporal framework built between ice core and marine sediment records. Our new data synthesis highlights non-synchronous maximum temperature changes between the two hemispheres with the Southern Ocean and Antarctica records showing an early warming compared to North Atlantic records. We also observe warmer than present-day conditions that occur for a longer time period in southern high latitudes than in northern high latitudes. Finally, the amplitude of temperature changes at high northern latitudes is larger compared to high southern latitude temperature changes recorded at the onset and the demise of the LIG. We have also compiled four data-based time slices with temperature anomalies (compared to present-day conditions) at 115 ka, 120 ka, 125 ka and 130 ka and quantitatively estimated temperature uncertainties that include relative dating errors. This provides an improved benchmark for performing more robust model-data comparison. The surface temperature simulated by two General Circulation Models (CCSM3 and HadCM3) for 130 ka and 125 ka is compared to the corresponding time slice data synthesis. This comparison shows that the models predict warmer than present conditions earlier than documented in the North Atlantic, while neither model is able to produce the reconstructed early Southern Ocean and Antarctic warming. Our results highlight the importance of producing a sequence of time slices rather than one single time slice averaging the LIG climate conditions

    Sexuality generates diversity in the Aflatoxin Gene cluster: evidence on a global scale

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    Aflatoxins are produced by Aspergillus flavus and A. parasiticus in oil-rich seed and grain crops and are a serious problem in agriculture, with aflatoxin B1 being the most carcinogenic natural compound known. Sexual reproduction in these species occurs between individuals belonging to different vegetative compatibility groups (VCGs). We examined natural genetic variation in 758 isolates of A. flavus, A. parasiticus and A. minisclerotigenes sampled from single peanut fields in the United States (Georgia), Africa (Benin), Argentina (CoÂŽrdoba), Australia (Queensland) and India (Karnataka). Analysis of DNA sequence variation across multiple intergenic regions in the aflatoxin gene clusters of A. flavus, A. parasiticus and A. minisclerotigenes revealed significant linkage disequilibrium (LD) organized into distinct blocks that are conserved across different localities, suggesting that genetic recombination is nonrandom and a global occurrence. To assess the contributions of asexual and sexual reproduction to fixation and maintenance of toxin chemotype diversity in populations from each locality/species, we tested the null hypothesis of an equal number of MAT1-1 and MAT1-2 mating-type individuals, which is indicative of a sexually recombining population. All samples were clone-corrected using multi-locus sequence typing which associates closely with VCG. For both A. flavus and A. parasiticus, when the proportions of MAT1-1 and MAT1-2 were significantly different, there was more extensive LD in the aflatoxin cluster and populations were fixed for specific toxin chemotype classes, either the non-aflatoxigenic class in A. flavus or the B1-dominant and G1-dominant classes in A. parasiticus. A mating type ratio close to 1:1 in A. flavus, A. parasiticus and A. minisclerotigenes was associated with higher recombination rates in the aflatoxin cluster and less pronounced chemotype differences in populations. This work shows that the reproductive nature of the population (more sexual versus more asexual) is predictive of aflatoxin chemotype diversity in these agriculturally important fungi.Fil: Moore, Geromy G.. United States Department of Agriculture; Estados UnidosFil: Elliott, Jacalyn L.. University Of North Carolina; Estados UnidosFil: Singh, Rakhi. University Of North Carolina; Estados UnidosFil: Horn, Bruce W.. United States Department Of Agriculture; Estados UnidosFil: Dorner, Jeo W.. United States Department Of Agriculture; Estados UnidosFil: Stone, Eric A.. University Of North Carolina; Estados UnidosFil: Chulze, Sofia Noemi. Universidad Nacional de RĂ­o Cuarto. Facultad de Ciencias Exactas, FisicoquĂ­micas y Naturales. Departamento de MicrobiologĂ­a E InmunologĂ­a; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Barros, GermĂĄn Gustavo. Universidad Nacional de RĂ­o Cuarto. Facultad de Ciencias Exactas, FisicoquĂ­micas y Naturales. Departamento de MicrobiologĂ­a E InmunologĂ­a; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Naik, Manjunath K.. College of Agriculture. Department of Plant Pathology; IndiaFil: Wright, Graeme C.. Department of Primary Industries; AustraliaFil: Hell, Kerstin. International Institute of Tropical Agriculture; BenĂ­nFil: Carbone, Ignazio. University Of North Carolina; Estados Unido

    Sexuality Generates Diversity in the Aflatoxin Gene Cluster: Evidence on a Global Scale

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    Aflatoxins are produced by Aspergillus flavus and A. parasiticus in oil-rich seed and grain crops and are a serious problem in agriculture, with aflatoxin B₁ being the most carcinogenic natural compound known. Sexual reproduction in these species occurs between individuals belonging to different vegetative compatibility groups (VCGs). We examined natural genetic variation in 758 isolates of A. flavus, A. parasiticus and A. minisclerotigenes sampled from single peanut fields in the United States (Georgia), Africa (Benin), Argentina (CĂłrdoba), Australia (Queensland) and India (Karnataka). Analysis of DNA sequence variation across multiple intergenic regions in the aflatoxin gene clusters of A. flavus, A. parasiticus and A. minisclerotigenes revealed significant linkage disequilibrium (LD) organized into distinct blocks that are conserved across different localities, suggesting that genetic recombination is nonrandom and a global occurrence. To assess the contributions of asexual and sexual reproduction to fixation and maintenance of toxin chemotype diversity in populations from each locality/species, we tested the null hypothesis of an equal number of MAT1-1 and MAT1-2 mating-type individuals, which is indicative of a sexually recombining population. All samples were clone-corrected using multi-locus sequence typing which associates closely with VCG. For both A. flavus and A. parasiticus, when the proportions of MAT1-1 and MAT1-2 were significantly different, there was more extensive LD in the aflatoxin cluster and populations were fixed for specific toxin chemotype classes, either the non-aflatoxigenic class in A. flavus or the B₁-dominant and G₁-dominant classes in A. parasiticus. A mating type ratio close to 1∶1 in A. flavus, A. parasiticus and A. minisclerotigenes was associated with higher recombination rates in the aflatoxin cluster and less pronounced chemotype differences in populations. This work shows that the reproductive nature of the population (more sexual versus more asexual) is predictive of aflatoxin chemotype diversity in these agriculturally important fungi

    Epistasis dominates the genetic architecture of Drosophila quantitative traits

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    Epistasis-nonlinear genetic interactions between polymorphic loci-is the genetic basis of canalization and speciation, and epistatic interactions can be used to infer genetic networks affecting quantitative traits. However, the role that epistasis plays in the genetic architecture of quantitative traits is controversial. Here, we compared the genetic architecture of three Drosophila life history traits in the sequenced inbred lines of the Drosophila melanogaster Genetic Reference Panel (DGRP) and a large outbred, advanced intercross population derived from 40 DGRP lines (Flyland). We assessed allele frequency changes between pools of individuals at the extremes of the distribution for each trait in the Flyland population by deep DNA sequencing. The genetic architecture of all traits was highly polygenic in both analyses. Surprisingly, none of the SNPs associated with the traits in Flyland replicated in the DGRP and vice versa. However, the majority of these SNPs participated in at least one epistatic interaction in the DGRP. Despite apparent additive effects at largely distinct loci in the two populations, the epistatic interactions perturbed common, biologically plausible, and highly connected genetic networks. Our analysis underscores the importance of epistasis as a principal factor that determines variation for quantitative traits and provides a means to uncover genetic networks affecting these traits. Knowledge of epistatic networks will contribute to our understanding of the genetic basis of evolutionarily and clinically important traits and enhance predictive ability at an individualized level in medicine and agricultur

    Efficacy and safety of fluticasone furoate 100 Όg and 200 Όg once daily in the treatment of moderate-severe asthma in adults and adolescents: a 24-week randomised study

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    Background: Inhaled corticosteroids are a mainstay of therapy for persistent asthma, but suboptimal adherence with twice-daily use is widespread. Fluticasone furoate (FF) is a new inhaled corticosteroid (ICS) suitable for once-daily dosing in asthma. This study was performed to descriptively assess the efficacy and safety of two doses of FF, with no planned formal statistical hypothesis testing. Methods: This was a 24-week double-blind, multicentre, parallel-group study (NCT01431950). Patients aged ≄ 12 years with moderate-severe persistent asthma and uncontrolled on mid-high dose ICS were stratified by baseline FEV1 and randomised (1:1) to treatment with FF 100 ÎŒg or 200 ÎŒg once daily in the evening. The primary endpoint was change from baseline trough FEV1 after 24 weeks; secondary and other endpoints included peak expiratory flow (PEF) and rescue-free and symptom-free 24-hour periods over Weeks 1–24, and Asthma Control Testℱ (ACT) score at Week 24. A pre-specified subgroup analysis of patients by randomisation strata was performed for the primary and selected secondary and other endpoints. Safety assessments included adverse events, laboratory and vital sign measurements, and change from baseline in 24-hour urinary cortisol at Week 24. Results: With FF 100 ÎŒg and 200 ÎŒg, least squares mean trough FEV1 improved from baseline by 208 mL and 284 mL, respectively, at Week 24; treatment difference: 77 mL (95% CI: –39, 192). Similar improvements from baseline in rescue- and symptom-free periods, and morning and evening PEF were observed in both groups. Patients were 42% more likely to be well-controlled (ACT score ≄ 20) with FF 200 ÎŒg than with FF 100 ÎŒg. Slightly more patients receiving FF 200 ÎŒg vs. FF 100 ÎŒg reported adverse events (63% vs. 59%) and events deemed treatment related (5% vs. <1%). Seven serious adverse events (FF 200 ÎŒg 4; FF 100 ÎŒg 3) were reported, none of which were deemed treatment related. No clinically relevant effects of either dose on 24-hour urinary cortisol were observed. Conclusion: Improvements from baseline in trough FEV1 were observed after 24 weeks of treatment with both doses of FF, with a numerically greater improvement in FEV1 observed in patients receiving FF 200 ÎŒg. Secondary endpoint findings were similar between groups. No safety concerns were identified during the study

    Identification of RNA binding motif proteins essential for cardiovascular development

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    Background We recently identified Rbm24 as a novel gene expressed during mouse cardiac development. Due to its tightly restricted and persistent expression from formation of the cardiac crescent onwards and later in forming vasculature we posited it to be a key player in cardiogenesis with additional roles in vasculogenesis and angiogenesis. Results To determine the role of this gene in cardiac development, we have identified its zebrafish orthologs (rbm24a and rbm24b), and functionally evaluated them during zebrafish embryogenesis. Consistent with our underlying hypothesis, reduction in expression of either ortholog through injection of morpholino antisense oligonucleotides results in cardiogenic defects including cardiac looping and reduced circulation, leading to increasing pericardial edema over time. Additionally, morphant embryos for either ortholog display incompletely overlapping defects in the forming vasculature of the dorsal aorta (DA), posterior caudal vein (PCV) and caudal vein (CV) which are the first blood vessels to form in the embryo. Vasculogenesis and early angiogenesis in the trunk were similarly compromised in rbm24 morphant embryos at 48 hours post fertilization (hpf). Subsequent vascular maintenance was impaired in both rbm24 morphants with substantial vessel degradation noted at 72 hpf. Conclusion Taken collectively, our functional data support the hypothesis that rbm24a and rbm24b are key developmental cardiac genes with unequal roles in cardiovascular formation

    Evaluation of Services Provided to Pregnant African Refugees by Catholic Social Services Refugee Resettlement Agency in Dayton Ohio

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    In 2016 Public Health - Dayton and Montgomery County declared birth outcomes the number one priority in their Community Health Improvement Plan. To improve the infant mortality rate (IMR), racial disparities must be address and considerations should be given to Dayton’s newest and most vulnerable neighbors. Dayton receives between 200 and 250 refugees each year, 70% of whom are from the Democratic Republic of the Congo. African refugees have higher infant mortally and poorer birth outcomes than native populations in the U.S. Early and regular prenatal care is protective against infant mortality, and African refugees consistently report delayed and infrequent prenatal care. Five categories affect utilization of prenatal services by African refugees; migration factors, cultural factors, treatment and communication factors, socioeconomic and accessibility factors, and social and psychological factors. This paper describes the services that Catholic Social Services (CSS) Refugee Resettlement Agency provides to newly-arrived pregnant refugees and compares these services to published guidelines and best practice models. When compared, CSS provide adequate services to address socioeconomic and accessibility factors through funding provided by the Department of State. While CSS provided some services towards the other four categories, none of them are comprehensive. The acculturation process provides an opportunity for CSS to address migration and cultural factors. But it is through strong community partnerships with local stakeholders that CSS can provide comprehensive services to address all the factors that affect prenatal care utilization in African refugees
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