3,180 research outputs found

    Realist synthesis: a critique and an alternative

    Get PDF
    Realist synthesis is often offered as a useful strategy to understand intervention complexity. Its unique selling point is its basis in a critical realist philosophy of science. However, we argue that the philosophical basis of current approaches to realist synthesis is closer to positivism, notably the focus on bringing a theoretical reduction to complex problems, a strategy eschewed in critical realism’s concern with complex independent ontology. We critique three recently published reviews to illustrate our arguments and apply an analytic strategy to findings from a realist review that, we argue, is more in line with critical realism

    Numerical Solution of the Two-Dimensional Gross-Pitaevskii Equation for Trapped Interacting Atoms

    Full text link
    We present a numerical scheme for solving the time-independent nonlinear Gross-Pitaevskii equation in two dimensions describing the Bose-Einstein condensate of trapped interacting neutral atoms at zero temperature. The trap potential is taken to be of the harmonic-oscillator type and the interaction both attractive and repulsive. The Gross-Pitaevskii equation is numerically integrated consistent with the correct boundary conditions at the origin and in the asymptotic region. Rapid convergence is obtained in all cases studied. In the attractive case there is a limit to the maximum number of atoms in the condensate.Comment: 5 pages LATEX, 3 postscript figure

    Accountability, evaluation and the role of evidence for charitable funders

    Get PDF
    This paper explores the link between accountability, evaluation and identity in the context of charitable funders. We argue that the notion of ‘evidence based’ action has influenced these charities to make claims for their evaluation processes that are established to account for activity rather then to generate knowledge. Although the terms evaluation and accountability are frequently used interchangeably, there is an essential difference as the site of interest in accountability is the relationship between funder and funded, whilst for evaluation, it is quality of knowledge produced. We look at the consequences of this distinction on identity for two funders in an analysis of website pamphlets, published to promote the use of evidence

    Blackbody excitation of an atom controlled by a tunable cavity

    Get PDF
    No description supplie

    ICP polishing of silicon for high quality optical resonators on a chip

    Full text link
    Miniature concave hollows, made by wet etching silicon through a circular mask, can be used as mirror substrates for building optical micro-cavities on a chip. In this paper we investigate how ICP polishing improves both shape and roughness of the mirror substrates. We characterise the evolution of the surfaces during the ICP polishing using white-light optical profilometry and atomic force microscopy. A surface roughness of 1 nm is reached, which reduces to 0.5 nm after coating with a high reflectivity dielectric. With such smooth mirrors, the optical cavity finesse is now limited by the shape of the underlying mirror

    Bar graph monitor

    Get PDF
    Bar graph monitor of pulse position modulation telemetry ground station equipment for sounding rocket

    Silage additive update: 1984

    Get PDF
    Numerous commercial silage additives, whose manufacturers claim will improve silage quality, are available to Kansas farmers and ranchers. We believe that these claims must ultimately be documented with farm-scale research. To date, Manhattan and Ft. Hays farm-scale silo results clearly indicate that a few silage additives do improve silage quality and are cost-effective. Several of them have consistently reduced in silo losses. But results probably will not be favorable with all additives under every farm condition. Nor will research results obtained with one commercial product in our trials also apply to other products on the market, however similar in ingredient formulation

    CULBACÂŽ and ADD-FÂŽ (formic acid) additives for sudangrass and high moisture shelled corn silages

    Get PDF
    Laboratory silos were used in three trials to evaluate sudangrass (slightly or moderately wilted) and high moisture corn silages, each receiving the following treatments: (1) control (no additive); (2) CULBACÂŽ dry; (3) CULBACÂŽ liquid; and (4) ADD-FÂŽ (formic acid). Although the 12 silages were well preserved visually, there were differences in their chemical compositions. Silages treated with CULBAC dry had the highest DM recoveries and probably the most efficient fermentations. As expected, formic acid restricted the amount of fermentation, but surprisingly, it did not improve DM recovery

    Clinical validity assessment of a breast cancer risk model combining genetic and clinical information

    Get PDF
    _Background:_ The extent to which common genetic variation can assist in breast cancer (BCa) risk assessment is unclear. We assessed the addition of risk information from a panel of BCa-associated single nucleotide polymorphisms (SNPs) on risk stratification offered by the Gail Model.

_Methods:_ We selected 7 validated SNPs from the literature and genotyped them among white women in a nested case-control study within the Women’s Health Initiative Clinical Trial. To model SNP risk, previously published odds ratios were combined multiplicatively. To produce a combined clinical/genetic risk, Gail Model risk estimates were multiplied by combined SNP odds ratios. We assessed classification performance using reclassification tables and receiver operating characteristic (ROC) curves. 

_Results:_ The SNP risk score was well calibrated and nearly independent of Gail risk, and the combined predictor was more predictive than either Gail risk or SNP risk alone. In ROC curve analysis, the combined score had an area under the curve (AUC) of 0.594 compared to 0.557 for Gail risk alone. For reclassification with 5-year risk thresholds at 1.5% and 2%, the net reclassification index (NRI) was 0.085 (Z = 4.3, P = 1.0×10^-5^). Focusing on women with Gail 5-year risk of 1.5-2% results in an NRI of 0.195 (Z = 3.8, P = 8.6×10^−5^).

_Conclusions:_ Combining clinical risk factors and validated common genetic risk factors results in improvement in classification of BCa risks in white, postmenopausal women. This may have implications for informing primary prevention and/or screening strategies. Future research should assess the clinical utility of such strategies.
&#xa

    Genome-wide analysis points to roles for extracellular matrix remodeling, the visual cycle, and neuronal development in myopia

    Get PDF
    Myopia, or nearsightedness, is the most common eye disorder, resulting primarily from excess elongation of the eye. The etiology of myopia, although known to be complex, is poorly understood. Here we report the largest ever genome-wide association study (43,360 participants) on myopia in Europeans. We performed a survival analysis on age of myopia onset and identified 19 significant associations (p < 5e-8), two of which are replications of earlier associations with refractive error. These 19 associations in total explain 2.7% of the variance in myopia age of onset, and point towards a number of different mechanisms behind the development of myopia. One association is in the gene PRSS56, which has previously been linked to abnormally small eyes; one is in a gene that forms part of the extracellular matrix (LAMA2); two are in or near genes involved in the regeneration of 11-cis-retinal (RGR and RDH5); two are near genes known to be involved in the growth and guidance of retinal ganglion cells (ZIC2, SFRP1); and five are in or near genes involved in neuronal signaling or development. These novel findings point towards multiple genetic factors involved in the development of myopia and suggest that complex interactions between extracellular matrix remodeling, neuronal development, and visual signals from the retina may underlie the development of myopia in humans
    • …
    corecore