1,303 research outputs found

    Data approximation strategies between generalized line scales and the influence of labels and spacing

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    Comparing sensory data gathered using different line scales is challenging. We tested whether adding internal labels to a generalized visual analog scale (gVAS) would improve comparability to a typical generalized labeled magnitude scale (gLMS). Untrained participants evaluated cheeses using one of four randomly assigned scales. Normalization to a cross‐modal standard and/or two gLMS transformations were applied to the data. Response means and distributions were lower for the gLMS than the gVAS, but no difference in resolving power was detected. The presence of labels, with or without line markings, caused categorical‐like lumping of responses. Closer low‐end label spacing for gLMS increased influenced participants to mark near higher intensity labels when they were evaluating low‐intensity samples. Although normalization reduced differences between scales, neither transformation nor normalization was supported as appropriate gLMS/gVAS approximation strategies. This study supports previous observations that neither scale offers a systematic advantage and that participant usage differences limit direct scale comparisons

    Chromospheric Variability in SDSS M Dwarfs. II. Short-Timescale H-alpha Variability

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    [Abridged] We present the first comprehensive study of short-timescale chromospheric H-alpha variability in M dwarfs using the individual 15 min spectroscopic exposures for 52,392 objects from the Sloan Digital Sky Survey. Our sample contains about 10^3-10^4 objects per spectral type bin in the range M0-M9, with a total of about 206,000 spectra and a typical number of 3 exposures per object (ranging up to a maximum of 30 exposures). Using this extensive data set we find that about 16% of the sources exhibit H-alpha emission in at least one exposure, and of those about 45% exhibit H-alpha emission in all of the available exposures. Within the sample of objects with H-alpha emission, only 26% are consistent with non-variable emission, independent of spectral type. The H-alpha variability, quantified in terms of the ratio of maximum to minimum H-alpha equivalent width (R_EW), and the ratio of the standard deviation to the mean (sigma_EW/), exhibits a rapid rise from M0 to M5, followed by a plateau and a possible decline in M9 objects. In particular, R_EW increases from a median value of about 1.8 for M0-M3 to about 2.5 for M7-M9, and variability with R_EW>10 is only observed in objects later than M5. For the combined sample we find that the R_EW values follow an exponential distribution with N(R_EW) exp[-(R_EW-1)/2]; for M5-M9 objects the characteristic scale is R_EW-1\approx 2.7, indicative of stronger variability. In addition, we find that objects with persistent H-alpha emission exhibit smaller values of R_EW than those with intermittent H-alpha emission. Based on these results we conclude that H-alpha variability in M dwarfs on timescales of 15 min to 1 hr increases with later spectral type, and that the variability is larger for intermittent sources.Comment: Submitted to ApJ; 20 pages, 15 figure

    A hazard model of the probability of medical school dropout in the United Kingdom

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    From individual level longitudinal data for two entire cohorts of medical students in UK universities, we use multilevel models to analyse the probability that an individual student will drop out of medical school. We find that academic preparedness—both in terms of previous subjects studied and levels of attainment therein—is the major influence on withdrawal by medical students. Additionally, males and more mature students are more likely to withdraw than females or younger students respectively. We find evidence that the factors influencing the decision to transfer course differ from those affecting the decision to drop out for other reasons

    To what extent can the activities of the South Australian Health in All Policies initiative be linked to population health outcomes using a program theory-based evaluation?

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    BACKGROUND: This paper reports on a five-year study using a theory-based program logic evaluation, and supporting survey and interview data to examine the extent to which the activites of the South Australian Health in All Policies initiative can be linked to population health outcomes. METHODS: Mixed-methods data were collected between 2012 and 2016 in South Australia (144 semi-structured key informant interviews; two electronic surveys of public servants in 2013 (n = 435) and 2015 (n = 483); analysis of state government policy documents; and construction of a program logic model to shape assessment of the feasibility of attribution to population health outcomes). RESULTS: Multiple actions on social determinants of health in a range of state government sectors were reported and most could be linked through a program logic model to making some contribution to future population health outcomes. Context strongly influences implementation; not all initiatives will be successful and experimentation is vital. Successful initiatives included HiAP influencing the urban planning department to be more concerned with the health impacts of planning decisions, and encouraging the environment department to be concerned with the health impacts of its work. CONCLUSIONS: The theory-based program logic suggests that SA HiAP facilitated improved population health through working with multiple government departments. Public servants came to appreciate how their sectors impact on health. Program logic is a mechanism to evaluate complex public health interventions in a way that takes account of political and economic contexts. SA HiAP was mainly successful in avoiding lifestyle drift in strategy. The initiative encouraged a range of state government departments to tackle conditions of daily living. The broader underpinning factors dictating the distribution of power, money and resources were not addressed by HiAP. This reflects HiAP's use of a consensus model which was driven by (rather than drove) state priorities and sought 'win-win' strategies

    Carbon balance of a restored and cutover raised bog: implications for restoration and comparison to global trends

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    The net ecosystem exchange (NEE) and methane (CH4) flux were measured by chamber measurements for five distinct ecotypes (areas with unique eco-hydrological characteristics) at Abbeyleix Bog in the Irish midlands over a 2-year period. The ecotypes ranged from those with high-quality peat-forming vegetation to communities indicative of degraded, drained conditions. Three of these ecotypes were located in an area where peat was extracted by hand and then abandoned and left to revegetate naturally at least 50 years prior to the start of the study. Two of the ecotypes were located on an adjacent raised bog, which although never mined for peat, was impacted by shallow drainage and then restored (by drain blocking) 6 years prior to the start of the study. Other major aspects of the carbon (C) balance, including dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and open-water CO2 evasion, were quantified for a catchment area at the study site over the same 2-year period. The ecotype average annual ecotype C balance ranged from a net C sink of -58±60&thinsp;g&thinsp;C&thinsp;m−2&thinsp;yr−1, comparable to studies of intact peatlands, to a substantial C source of +205±80&thinsp;g&thinsp;C m−2&thinsp;yr−1, with NEE being the most variable component of the C balance among the five ecotypes. Ecotype annual CH4 flux ranged from 2.7±1.4&thinsp;g&thinsp;C-CH4&thinsp;m−2&thinsp;yr−1 to 14.2±4.8&thinsp;g&thinsp;C-CH4&thinsp;m−2&thinsp;yr−1. Average annual aquatic C losses were 14.4&thinsp;g&thinsp;C&thinsp;m−2&thinsp;yr−1 with DOC, DIC, and CO2 evasion of 10.4&thinsp;g&thinsp;C&thinsp;m−2&thinsp;yr−1, 1.3&thinsp;g&thinsp;C&thinsp;m−2&thinsp;yr−1, and 2.7&thinsp;g&thinsp;C&thinsp;m−2&thinsp;yr−1, respectively. A statistically significant negative correlation was found between the mean annual water table (MAWT) and the plot-scale NEE but not the global warming potential (GWP). However, a significant negative correlation was observed between the plot-scale percentage of Sphagnum moss cover and the GWP, highlighting the importance of regenerating this keystone genus as a climate change mitigation strategy in peatland restoration. The data from this study were then compared to the rapidly growing number of peatland C balance studies across boreal and temperate regions. The trend in NEE and CH4 flux with respect to MAWT was compared for the five ecotypes in this study and literature data from degraded/restored/recovering peatlands, intact peatlands, and bare peat sites.</p

    Trends in the Statistical Assessment of Reliability

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    Changes in technology have had and will continue to have a strong effect on changes in the area of statistical assessment of reliability data. These changes include higher levels of integration in electronics, improvements in measurement technology and the deployment of sensors and smart chips into more products, dramatically improved computing power and storage technology, and the development of new, powerful statistical methods for graphics, inference, and experimental design and reliability test planning. This paper traces some of the history of the development of statistical methods for reliability assessment and makes some predictions about the future

    特別支援教育専攻学生を対象とした障害理解のための教材開発(2)―糖尿病・血友病等の「自己注射」場面を中心にした教材―

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     特別支援教育専攻学生の指導では、対象とする障害児・者が活用する機器・道具を提示し、その使用法の解説がなされてきた。これは感覚・情報系障害領域では指導上意義がある。また肢体不自由・運動障害系では、車イスや生活補助具、障害体験グッズなどが障害理解教材として活用されてきた。しかし病弱教育領域では、子どもの困難理解につながる「病気体験」は、健常学生にはできない。そこで教員は、病院見学、療養生活の映像資料等を活用し、病気の影響や困難をイメージさせる方法をとることが多い。本研究では糖尿病および血友病を例にとり、病気による「困難」を体験・体感させる教材について検討した。糖尿病・血友病の自己注射モデルを提示し、その作製・改善とそれを使用した授業経過を分析対象とした。学生による試作及び改良モデルは、自己注射実施時の困難・不安・躊躇を「体感」させることを目的としているが、作製過程そのものが、学生による困難・不安・躊躇といった自己注射実施を必要とする疾患のもつ障害特性の理解を促進することが推察された
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