1,149 research outputs found

    Adsorption of Fibrinogen on Thin Oriented Poly(Tetrafluoroethylene) (PTFE) Fibres Studied by Scanning Force Microscopy

    Get PDF
    We have investigated fibrinogen adsorption on ordered poly(tetrafluoroethylene), PTFE, fibres deposited on hydrophilic and hydrophobic silicon substrates. Fibrinogen molecules appear to adsorb with their long axis perpendicular to the fibre direction for PTFE fibres having widths of less than 100 nm. On these thin fibres, fibrinogen apparently forms close packed bands or clusters, consisting of small integer numbers of molecules arranged parallel to each other. On broader (\u3e 100 nm) PTFE fibres, the fibrinogen forms two dimensional networks. The orientation of the molecules in these networks is random in the central flat part of the fibres but perpendicular to the fibre direction at the fibre edges. As a tentative explanation, we propose that the observed orientation may be linked to the radius of curvature of the fibre surface

    Deep learning exotic hadrons

    Full text link
    We perform the first amplitude analysis of experimental data using deep neural networks to determine the nature of an exotic hadron. Specifically, we study the line shape of the Pc(4312) signal reported by the LHCb collaboration, and we find that its most likely interpretation is that of a virtual state. This method can be applied to other near-threshold resonance candidates

    Psychotherapy Versus Pharmacotherapy For Posttraumatic Stress Disorder: Systemic Review And Meta-Analyses To Determine First-Line Treatments

    Get PDF
    Background: Current clinical practice guidelines (CPGs) for posttraumatic stress disorder (PTSD) offer contradictory recommendations regarding use of medications or psychotherapy as first-line treatment. Direct head-to-head comparisons are lacking. Methods: Systemic review of Medline, EMBASE, PILOTS, Cochrane Central Register of Controlled Trials, PsycINFO, and Global Health Library was conducted without language restrictions. Randomized clinical trials \u3e8 weeks in duration using structured clinical interview-based outcome measures, active-control conditions (e.g. supportive psychotherapy), and intent-to-treat analysis were selected for analyses. Independent review, data abstraction, and bias assessment were performed using standardized processes. Study outcomes were grouped around conventional follow-up time periods (3, 6, and 9 months). Combined effect sizes were computed using meta-analyses for medication versus control, medication pre-/posttreatment, psychotherapy versus control, and psychotherapy pre-/posttreatment. Results: Effect sizes for trauma-focused psychotherapies (TFPs) versus active control conditions were greater than medications versus placebo and other psychotherapies versus active controls. TFPs resulted in greater sustained benefit over time than medications. Sertraline, venlafaxine, and nefazodone outperformed other medications, although potential for methodological biases were high. Improvement following paroxetine and fluoxetine treatment was small. Venlafaxine and stress inoculation training (SIT) demonstrated large initial effects that decreased over time. Bupropion, citalopram, divalproex, mirtazapine, tiagabine, and topiramate failed to differentiate from placebo. Aripiprazole, divalproex, guanfacine, and olanzapine failed to differentiate from placebo when combined with an antidepressant. Conclusions: Study findings support use of TFPs over nontrauma-focused psychotherapy or medication as first-line interventions. Second-line interventions include SIT, and potentially sertraline or venlafaxine, rather than entire classes of medication, such as SSRIs. Future revisions of CPGs should prioritize studies that utilize active controls over waitlist or treatment-as-usual conditions. Direct head-to-head trials of TFPs versus sertraline or venlafaxine are needed

    Multiple causes of interannual sea surface temperature variability in the equatorial Atlantic Ocean

    Get PDF
    The eastern equatorial Atlantic Ocean is subject to interannual fluctuations of sea surface temperatures, with climatic impacts on the surrounding continents. The dynamic mechanism underlying Atlantic temperature variability is thought to be similar to that of the El Nino/Southern Oscillation (ENSO) in the equatorial Pacific, where air-sea coupling leads to a positive feedback between surface winds in the western basin, sea surface temperature in the eastern basin, and equatorial oceanic heat content. Here we use a suite of observational data, climate reanalysis products, and general circulation model simulations to reassess the factors driving the interannual variability. We show that some of the warm events can not be explained by previously identified equatorial wind stress forcing and ENSO-like dynamics. Instead, these events are driven by a mechanism in which surface wind forcing just north of the equator induces warm ocean temperature anomalies that are subsequently advected toward the equator. We find the surface wind patterns are associated with long-lived subtropical sea surface temperature anomalies and suggest they therefore reflect a link between equatorial and subtropical Atlantic variability

    Fecal Short-Chain Fatty Acid Ratios as Related to Gastrointestinal and Depressive Symptoms in Young Adults

    Get PDF
    Objective: Short-chain fatty acids (SCFAs) are produced by the gut microbiota and may reflect health. Gut symptoms are common in individuals with depressive disorders, and recent data indicate relationships between gut microbiota and psychiatric health. We aimed to investigate potential associations between SCFAs and self-reported depressive and gut symptoms in young adults.Methods: Fecal samples from 164 individuals (125 were patients with psychiatric disorders: mean [standard deviation] age = 21.9 [2.6] years, 14% men; 39 nonpsychiatric controls: age = 28.5 [9.5] years, 38% men) were analyzed for the SCFA acetate, butyrate, and propionate by nuclear magnetic resonance spectroscopy. We then compared SCFA ratios with dimensional measures of self-reported depressive and gut symptoms.Results: Depressive symptoms showed a positive association with acetate levels (rho = 0.235, p =.003) and negative associations with both butyrate (rho = -0.195, p =.014) and propionate levels (rho = -0.201, p =.009) in relation to total SCFA levels. Furthermore, symptoms of diarrhea showed positive associations with acetate (rho = 0.217, p =.010) and negative associations with propionate in relation to total SCFA levels (rho = 0.229, p = 0-007). Cluster analysis revealed a heterogeneous pattern where shifts in SCFA ratios were observed in individuals with elevated levels of depressive symptoms, elevated levels of gut symptoms, or both.Conclusions: Shifts in SCFAs are associated with both depressive symptoms and gut symptoms in young adults and may have of relevance for treatment
    corecore