1,109 research outputs found

    Laser Calibration System for Time of Flight Scintillator Arrays

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    A laser calibration system was developed for monitoring and calibrating time of flight (TOF) scintillating detector arrays. The system includes setups for both small- and large-scale scintillator arrays. Following test-bench characterization, the laser system was recently commissioned in experimental Hall B at the Thomas Jefferson National Accelerator Facility for use on the new Backward Angle Neutron Detector (BAND) scintillator array. The system successfully provided time walk corrections, absolute time calibration, and TOF drift correction for the scintillators in BAND. This showcases the general applicability of the system for use on high-precision TOF detectors.Comment: 11 pages, 11 figure

    HDAC-mediated control of ERK- and PI3K-dependent TGF-β-induced extracellular matrix-regulating genes

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    Histone deacetylases (HDACs) regulate the acetylation of histones in the control of gene expression. Many non-histone proteins are also targeted for acetylation, including TGF-ß signalling pathway components such as Smad2, Smad3 and Smad7. Our studies in mouse C3H10T1/2 fibroblasts suggested that a number of TGF-ß-induced genes that regulate matrix turnover are selectively regulated by HDACs. Blockade of HDAC activity with trichostatin A (TSA) abrogated the induction of a disintegrin and metalloproteinase 12 (Adam12) and tissue inhibitor of metalloproteinases-1 (Timp-1) genes by TGF-ß, whereas plasminogen activator inhibitor-1 (Pai-1) expression was unaffected. Analysis of the activation of cell signalling pathways demonstrated that TGF-ß induced robust ERK and PI3K activation with delayed kinetics compared to the phosphorylation of Smads. The TGF-ß induction of Adam12 and Timp-1 was dependent on such non-Smad signalling pathways and, importantly, HDAC inhibitors completely blocked their activation without affecting Smad signalling. Analysis of TGF-ß-induced Adam12 and Timp-1 expression and ERK/PI3K signalling in the presence of semi-selective HDAC inhibitors valproic acid, MS-275 and apicidin implicated a role for class I HDACs. Furthermore, depletion of HDAC3 by RNA interference significantly down-regulated TGF-ß-induced Adam12 and Timp-1 expression without modulating Pai-1 expression. Correlating with the effect of HDAC inhibitors, depletion of HDAC3 also blocked the activation of ERK and PI3K by TGF-ß. Collectively, these data confirm that HDACs, and in particular HDAC3, are required for activation of the ERK and PI3K signalling pathways by TGF-ß and for the subsequent gene induction dependent on these signalling pathways

    Participation factors in optional high school health and physical education

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    Student enrolment rates in optional health and physical education (HPE) classes have been steadily declining, to the point where most Ontario students stop taking HPE after completion of their one required credit, typically taken in grade nine. This study looked at factors that could contribute to HPE enrolment, sampling 227 grade ten students from five schools. These factors included selfefficacy (SE), perceived autonomy support (PAS), task value (TV), motivational regulation (autonomous, AR; controlled, CR), HPE grade average and body size discrepancy (BSD). Qualitative information was also gathered from students regarding likes and dislikes ofHPE, as well as reasons for their HPE enrolment choice. Cronbach Alpha values of each scale fell within acceptable values. ANOVA analysis revealed differences between enrolment groups in SE, TV, AR, HPE grade average, and BSD (p < .05). Reasons students reported for not taking HPE included a dislike of health classes, scheduling challenges, not needing HPE for future endeavors, concerns about social self-presentation, and a dislike of sports and/or competition. This research shows important differences between students and their HPE class choices and calls for a re-evaluation of how HPE classes are structured, advertised and scheduled by high school practitioners. Future works should look toward what other factors could be at play in students' decisions for or against optional HPE and how those factors interact with the constructs that were found to be of significance in this study. Keywords: Health and physical education, high school students, participation

    稲垣足穂『少年愛の美学』の読書論的研究 --念者としての語り--

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    千葉大学大学院人文社会科学研究科研究プロジェクト報告書第144集 『パフォーマンスの民族誌的研究』橋本裕之

    The Dawn of Open Access to Phylogenetic Data

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    The scientific enterprise depends critically on the preservation of and open access to published data. This basic tenet applies acutely to phylogenies (estimates of evolutionary relationships among species). Increasingly, phylogenies are estimated from increasingly large, genome-scale datasets using increasingly complex statistical methods that require increasing levels of expertise and computational investment. Moreover, the resulting phylogenetic data provide an explicit historical perspective that critically informs research in a vast and growing number of scientific disciplines. One such use is the study of changes in rates of lineage diversification (speciation - extinction) through time. As part of a meta-analysis in this area, we sought to collect phylogenetic data (comprising nucleotide sequence alignment and tree files) from 217 studies published in 46 journals over a 13-year period. We document our attempts to procure those data (from online archives and by direct request to corresponding authors), and report results of analyses (using Bayesian logistic regression) to assess the impact of various factors on the success of our efforts. Overall, complete phylogenetic data for ~60% of these studies are effectively lost to science. Our study indicates that phylogenetic data are more likely to be deposited in online archives and/or shared upon request when: (1) the publishing journal has a strong data-sharing policy; (2) the publishing journal has a higher impact factor, and; (3) the data are requested from faculty rather than students. Although the situation appears dire, our analyses suggest that it is far from hopeless: recent initiatives by the scientific community -- including policy changes by journals and funding agencies -- are improving the state of affairs

    Stakeholders' role in improving Ghana's construction safety

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    Health and safety (H&S) management has traditionally been the responsibility of the contractor. Most often, contractors are blamed for the accidents and other ill health that occur on their construction sites. H&S performance is, however, enhanced when there is effective collaboration between those involved in the construction process. This paper therefore explores the role of stakeholders in promoting construction H&S in Ghana through public works procurement. The four main stakeholders identified and evaluated in this study are the government, the client (employer), the contractor and the employee(s). Seven interviewees (comprising procurement managers, consultants and quantity surveyors) from public institutions in Ghana participated in the research. Data were collected using semi-structured interviews and were thematically analysed. Results indicate a conflict in the perceived functions and relation of these stakeholders in the construction process. To address the constraint to improving construction H&S, certain recommendations are offered. These include the identification of specific individuals responsible for supervision and employee training, the development of H&S policies by the government and contracts that clearly outline the contractual obligations of all parties involved. Additionally, the specific roles and involvements of other stakeholders in the procurement process in improving construction H&S are also outlined

    Conscience, conscientiousness and virtue

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