1,102 research outputs found

    The psychology and method of personal youth guidance

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    Thesis (M.A.)--Boston University, 1938. This item was digitized by the Internet Archive

    Using Proxies to assess Quality of Life: A Review of the Issues and Challenges

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    Molecular Gas and Star Formation in the Cartwheel

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    Atacama Large Millimeter/submillimeter Array (ALMA) 12CO(J=1-0) observations are used to study the cold molecular ISM of the Cartwheel ring galaxy and its relation to HI and massive star formation (SF). CO moment maps find (2.69±0.05)×109(2.69\pm0.05)\times10^{9} M_{\odot} of H2_2 associated with the inner ring (72%) and nucleus (28%) for a Galactic I(CO)-to-N(H2) conversion factor (αCO\alpha_{\rm CO}). The spokes and disk are not detected. Analysis of the inner ring's CO kinematics show it to be expanding (Vexp=68.9±4.9V_{\rm exp}=68.9\pm4.9 km s1^{-1}) implying an 70\approx70 Myr age. Stack averaging reveals CO emission in the starburst outer ring for the first time, but only where HI surface density (ΣHI\Sigma_{\rm HI}) is high, representing MH2=(7.5±0.8)×108M_{\rm H_2}=(7.5\pm0.8)\times10^{8} M_{\odot} for a metallicity appropriate αCO\alpha_{\rm CO}, giving small ΣH2\Sigma_{\rm H_2} (3.73.7 M_{\odot} pc2^{-2}), molecular fraction (fmol=0.10f_{\rm mol}=0.10), and H2_2 depletion timescales (τmol50600\tau_{\rm mol} \approx50-600 Myr). Elsewhere in the outer ring ΣH22\Sigma_{\rm H_2}\lesssim 2 M_{\odot} pc2^{-2}, fmol0.1f_{\rm mol}\lesssim 0.1 and τmol140540\tau_{\rm mol}\lesssim 140-540 Myr (all 3σ3\sigma). The inner ring and nucleus are H2_2-dominated and are consistent with local spiral SF laws. ΣSFR\Sigma_{\rm SFR} in the outer ring appears independent of ΣH2\Sigma_{\rm H_2}, ΣHI\Sigma_{\rm HI} or ΣHI+H2\Sigma_{\rm HI+H_2}. The ISM's long confinement in the robustly star forming rings of the Cartwheel and AM0644-741 may result in either a large diffuse H2_2 component or an abundance of CO-faint low column density molecular clouds. The H2_2 content of evolved starburst rings may therefore be substantially larger. Due to its lower ΣSFR\Sigma_{\rm SFR} and age the Cartwheel's inner ring has yet to reach this state. Alternately, the outer ring may trigger efficient SF in an HI-dominated ISM.Comment: 10-pages text; 5-figure

    TreeToReads - a pipeline for simulating raw reads from phylogenies.

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    BackgroundUsing phylogenomic analysis tools for tracking pathogens has become standard practice in academia, public health agencies, and large industries. Using the same raw read genomic data as input, there are several different approaches being used to infer phylogenetic tree. These include many different SNP pipelines, wgMLST approaches, k-mer algorithms, whole genome alignment and others; each of these has advantages and disadvantages, some have been extensively validated, some are faster, some have higher resolution. A few of these analysis approaches are well-integrated into the regulatory process of US Federal agencies (e.g. the FDA's SNP pipeline for tracking foodborne pathogens). However, despite extensive validation on benchmark datasets and comparison with other pipelines, we lack methods for fully exploring the effects of multiple parameter values in each pipeline that can potentially have an effect on whether the correct phylogenetic tree is recovered.ResultsTo resolve this problem, we offer a program, TreeToReads, which can generate raw read data from mutated genomes simulated under a known phylogeny. This simulation pipeline allows direct comparisons of simulated and observed data in a controlled environment. At each step of these simulations, researchers can vary parameters of interest (e.g., input tree topology, amount of sequence divergence, rate of indels, read coverage, distance of reference genome, etc) to assess the effects of various parameter values on correctly calling SNPs and reconstructing an accurate tree.ConclusionsSuch critical assessments of the accuracy and robustness of analytical pipelines are essential to progress in both research and applied settings

    The Zeeman effects in ruthenium I

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Physics, 1941.Includes bibliographical references.by J. Rand McNally, Jr.M.S

    Developing an Easy Read version of the Adult Social Care Outcomes Toolkit (ASCOT)

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    Background: This paper reports the experiences of developing and pre-testing an Easy Read version of the Adult Social Care Outcomes Toolkit (ASCOT) for self-report by people with intellectual disabilities. Method: The study has combined survey development and pre-testing methods with approaches to create accessible information for people with intellectual disabilities. A working group assisted researchers in identifying appropriate question formats, pictures and wording. Focus groups and cognitive interviews were conducted to test various iterations of the instrument. Results: Substantial changes were made to the questionnaire, which included changes to illustrations, the wording of question stems and response options. Conclusions: The process demonstrated the benefits of involving people with intellectual disabilities in the design and testing of data collection instruments. Adequately adapted questionnaires can be useful tools to collect information from people with intellectual disabilities in survey research; however its limitations must be recognised

    Multiple Comparison Procedures, Trimmed Means And Transformed Statistics

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    A modification to testing pairwise comparisons that may provide better control of Type I errors in the presence of non-normality is to use a preliminary test for symmetry which determines whether data should be trimmed symmetrically or asymmetrically. Several pairwise MCPs were investigated, employing a test of symmetry with a number of heteroscedastic test statistics that used trimmed means and Winsorized variances. Results showed improved Type I error control than competing robust statistics
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