1,083 research outputs found

    The methodology for developing a prospective meta-analysis in the family planning community

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Prospective meta-analysis (PMA) is a collaborative research design in which individual sites perform randomized controlled trials (RCTs) and pool the data for meta-analysis. Members of the PMA collaboration agree upon specific research interventions and outcome measures, ideally before initiation but at least prior to any individual trial publishing results. This allows for uniform reporting of primary and secondary outcomes. With this approach, heterogeneity among trials contributing data for the final meta-analysis is minimized while each site maintains the freedom to design a specific trial. This paper describes the process of creating a PMA collaboration to evaluate the impact of misoprostol on ease of intrauterine device (IUD) insertion in nulliparous women.</p> <p>Methods</p> <p>After the principal investigator developed a preliminary PMA protocol, he identified potential collaborating investigators at other sites. One site already had a trial underway and another site was in the planning stages of a trial meeting PMA requirements. Investigators at six sites joined the PMA collaborative. Each site committed to enroll subjects to meet a pre-determined total sample size. A final common research plan and site responsibilities were developed and agreed upon through email and face-to-face meetings. Each site committed to contribute individual patient data to the PMA collaboration, and these data will be analyzed and prepared as a multi-site publication. Individual sites retain the ability to analyze and publish their site's independent findings.</p> <p>Results</p> <p>All six sites have obtained Institutional Review Board approval and each has obtained individual funding to meet the needs of that site's study. Sites have shared resources including study protocols and consents to decrease costs and improve study flow. This PMA protocol is registered with the Cochrane Collaboration and data will be analyzed according to Cochrane standards for meta-analysis.</p> <p>Conclusions</p> <p>PMA is a novel research method that improves meta-analysis by including several study sites, establishing uniform reporting of specific outcomes, and yet allowing some independence on the part of individual sites with respect to the conduct of research. The inclusion of several sites increases statistical power to address important clinical questions. Compared to multi-center trials, PMA methodology encourages collaboration, aids in the development of new investigators, decreases study costs, and decreases time to publication.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00613366">NCT00613366</a>, <a href="http://www.clinicaltrials.gov/ct2/show/NCT00886834">NCT00886834</a>, <a href="http://www.clinicaltrials.gov/ct2/show/NCT01001897">NCT01001897</a>, <a href="http://www.clinicaltrials.gov/ct2/show/NCT01147497">NCT01147497</a> and <a href="http://www.clinicaltrials.gov/ct2/show/NCT01307111">NCT01307111</a></p

    The differential hormonal milieu of morning versus evening, may have an impact on muscle hypertrophic potential

    Get PDF
    Substantial gains in muscle strength and hypertrophy are clearly associated with the routine performance of resistance training. What is less evident is the optimal timing of the resistance training stimulus to elicit these significant functional and structural skeletal muscle changes. Therefore, this investigation determined the impact of a single bout of resistance training performed either in the morning or evening upon acute anabolic signalling (insulin-like growth factor-binding protein-3 (IGFBP-3), myogenic index and differentiation) and catabolic processes (cortisol). Twenty-four male participants (age 21.4±1.9yrs, mass 83.7±13.7kg) with no sustained resistance training experience were allocated to a resistance exercise group (REP). Sixteen of the 24 participants were randomly selected to perform an additional non-exercising control group (CP) protocol. REP performed two bouts of resistance exercise (80% 1RM) in the morning (AM: 0800 hrs) and evening (PM: 1800 hrs), with the sessions separated by a minimum of 72 hours. Venous blood was collected immediately prior to, and 5 min after, each resistance exercise and control sessions. Serum cortisol and IGFBP-3 levels, myogenic index, myotube width, were determined at each sampling period. All data are reported as mean ± SEM, statistical significance was set at P≤0.05. As expected a significant reduction in evening cortisol concentration was observed at pre (AM: 98.4±10.5, PM: 49.8±4.4 ng/ml, P0.05). Timing of resistance training regimen in the evening appears to augment some markers of hypertrophic potential, with elevated IGFBP-3, suppressed cortisol and a superior cellular environment. Further investigation, to further elucidate the time course of peak anabolic signalling in morning vs evening training conditions, are timely

    Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

    Get PDF
    Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

    How long will it take? Conceptualizing the temporal dynamics of energy transitions

    Get PDF
    Transitioning away from our current global energy system is of paramount importance. The speed at which a transition can take place—its timing, or temporal dynamics—is a critical element of consideration. This study therefore investigates the issue of time in global and national energy transitions by asking: What does the mainstream academic literature suggest about the time scale of energy transitions? Additionally, what does some of the more recent empirical data related to transitions say, or challenge, about conventional views? In answering these questions, the article presents a “mainstream” view of energy transitions as long, protracted affairs, often taking decades to centuries to occur. However, the article then offers some empirical evidence that the predominant view of timing may not always be supported by the evidence. With this in mind, the final part of the article argues for more transparent conceptions and definitions of energy transitions, and it asks for analysis that recognizes the causal complexity underlying them

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

    Get PDF
    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

    Get PDF
    A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

    Borderline Personality Disorder Symptoms in College Students: The Complex Interplay between Alexithymia, Emotional Dysregulation and Rumination.

    Get PDF
    Both Emotional Cascade Theory and Linehan's Biosocial Theory suggest dysregulated behaviors associated with Borderline Personality Disorder (BPD) emerge, in part, because of cycles of rumination, poor emotional recognition and poor emotion regulation. In this study we examined relationships between rumination, alexithymia, and emotion regulation in predicting dysregulated behaviors associated with BPD (e.g. self-harm, substance use, aggression), and explored both indirect and moderating effects among these variables. The sample comprised 2261 college students who completed self-report measures of the aforementioned constructs. BPD symptoms, stress, family psychological illness, and alexithymia exerted direct effects on behaviors. Symptoms had an indirect effect on behaviors through rumination, alexithymia and emotional dysregulation. In addition, the relationship between symptoms and dysregulated behaviors was conditional on level of rumination and alexithymia. Implications for early identification and treatment of BPD and related behaviors in college settings are discussed

    Feedback Enhances Feedforward Figure-Ground Segmentation by Changing Firing Mode

    Get PDF
    In the visual cortex, feedback projections are conjectured to be crucial in figure-ground segregation. However, the precise function of feedback herein is unclear. Here we tested a hypothetical model of reentrant feedback. We used a previous developed 2-layered feedforwardspiking network that is able to segregate figure from ground and included feedback connections. Our computer model data show that without feedback, neurons respond with regular low-frequency (∼9 Hz) bursting to a figure-ground stimulus. After including feedback the firing pattern changed into a regular (tonic) spiking pattern. In this state, we found an extra enhancement of figure responses and a further suppression of background responses resulting in a stronger figure-ground signal. Such push-pull effect was confirmed by comparing the figure-ground responses withthe responses to a homogenous texture. We propose that feedback controlsfigure-ground segregation by influencing the neural firing patterns of feedforward projecting neurons

    Safety and Immunogenicity Study of Multiclade HIV-1 Adenoviral Vector Vaccine Alone or as Boost following a Multiclade HIV-1 DNA Vaccine in Africa

    Get PDF
    We conducted a double-blind, randomized, placebo-controlled Phase I study of a recombinant replication-defective adenovirus type 5 (rAd5) vector expressing HIV-1 Gag and Pol from subtype B and Env from subtypes A, B and C, given alone or as boost following a DNA plasmid vaccine expressing the same HIV-1 proteins plus Nef, in 114 healthy HIV-uninfected African adults.Volunteers were randomized to 4 groups receiving the rAd5 vaccine intramuscularly at dosage levels of 1×10(10) or 1×10(11) particle units (PU) either alone or as boost following 3 injections of the DNA vaccine given at 4 mg/dose intramuscularly by needle-free injection using Biojector® 2000. Safety and immunogenicity were evaluated for 12 months. Both vaccines were well-tolerated. Overall, 62% and 86% of vaccine recipients in the rAd5 alone and DNA prime - rAd5 boost groups, respectively, responded to the HIV-1 proteins by an interferon-gamma (IFN-γ) ELISPOT. The frequency of immune responses was independent of rAd5 dosage levels. The highest frequency of responses after rAd5 alone was detected at 6 weeks; after DNA prime - rAd5 boost, at 6 months (end of study). At baseline, neutralizing antibodies against Ad5 were present in 81% of volunteers; the distribution was similar across the 4 groups. Pre-existing immunity to Ad5 did not appear to have a significant impact on reactogenicity or immune response rates to HIV antigens by IFN-γ ELISPOT. Binding antibodies against Env were detected in up to 100% recipients of DNA prime - rAd5 boost. One volunteer acquired HIV infection after the study ended, two years after receipt of rAd5 alone.The HIV-1 rAd5 vaccine, either alone or as a boost following HIV-1 DNA vaccine, was well-tolerated and immunogenic in African adults. DNA priming increased the frequency and magnitude of cellular and humoral immune responses, but there was no effect of rAd5 dosage on immunogenicity endpoints.ClinicalTrials.gov NCT00124007
    corecore