9,818 research outputs found

    Elevated Depressive Symptoms In A Community Sample Of African-Americans And Whites

    Full text link
    This study examined demographic and psychosocial correlates of elevated depressive symptoms among African-Americans and Whites from comparable socioeconomic and neighborhood backgrounds. 851 African-Americans and 597 Whites from adjacent census tracts were interviewed using previously validated indicators of depressive symptoms, social support, religious practices and various demographic characteristics. More Whites than African-Americans reported elevated depressive symptoms and the groups also differed on several demographic variables and psychosocial variables. Employment, marital status and age were salient demographic covariates for African Americans, while income was for Whites. For both groups, social support and church attendance were inversely associated with depressive symptoms. Prayer was positively associated with depressive symptoms. Future research should explore within racial/ethnic group variations in depressive symptoms. Insights also are needed into possible changes over time in the relationship between religious variables and depressive symptoms, and how social support limits depressive symptoms in diverse populations

    Severe Lumbar Disability Is Associated With Decreased Psoas Cross-Sectional Area in Degenerative Spondylolisthesis

    Get PDF
    Study Design: Retrospective cohort. Objectives: Alterations in lumbar paraspinal muscle cross-sectional area (CSA) may correlate with lumbar pathology. The purpose of this study was to compare paraspinal CSA in patients with degenerative spondylolisthesis and severe lumbar disability to those with mild or moderate lumbar disability, as determined by the Oswestry Disability Index (ODI). Methods: We retrospectively reviewed the medical records of 101 patients undergoing lumbar fusion for degenerative spondylolisthesis. Patients were divided into ODI score ≤40 (mild/moderate disability, MMD) and ODI score \u3e40 (severe disability, SD) groups. The total CSA of the psoas and paraspinal muscles were measured on preoperative magnetic resonance imaging (MRI). Results: There were 37 patients in the SD group and 64 in the MMD group. Average age and body mass index were similar between groups. For the paraspinal muscles, we were unable to demonstrate any significant differences in total CSA between the groups. Psoas muscle CSA was significantly decreased in the SD group compared with the MMD group (1010.08 vs 1178.6 mm2, P =.041). Multivariate analysis found that psoas CSA in the upper quartile was significantly protective against severe disability (P =.013). Conclusions: We found that patients with severe lumbar disability had no significant differences in posterior lumbar paraspinal CSA when compared with those with mild/moderate disability. However, severely disabled patients had significantly decreased psoas CSA, and larger psoas CSA was strongly protective against severe disability, suggestive of a potential association with psoas atrophy and worsening severity of lumbar pathology. © The Author(s) 2018

    A Mean-Field Theory for Coarsening Faceted Surfaces

    Full text link
    A mean-field theory is developed for the scale-invariant length distributions observed during the coarsening of one-dimensional faceted surfaces. This theory closely follows the Lifshitz-Slyozov-Wagner theory of Ostwald ripening in two-phase systems [1-3], but the mechanism of coarsening in faceted surfaces requires the addition of convolution terms recalling the work of Smoluchowski [4] and Schumann [5] on coalescence. The model is solved by the exponential distribution, but agreement with experiment is limited by the assumption that neighboring facet lengths are uncorrelated. However, the method concisely describes the essential processes operating in the scaling state, illuminates a clear path for future refinement, and offers a framework for the investigation of faceted surfaces evolving under arbitrary dynamics. [1] I. Lifshitz, V. Slezov, Soviet Physics JETP 38 (1959) 331-339. [2] I. Lifshitz, V. Slyozov, J. Phys. Chem. Solids 19 (1961) 35-50. [3] C. Wagner, Elektrochemie 65 (1961) 581-591. [4] M. von Smoluchowski, Physikalische Zeitschrift 17 (1916) 557-571. [5] T. Schumann, J. Roy. Met. Soc. 66 (1940) 195-207

    A Methodology to Assist Faculty in Developing Successful Approaches for Achieving Learner Centered Information Systems Curriculum Outcomes: Team Based Methods

    Get PDF
    All industries face the interrelated challenges of indentifying and training the critical skills needed to be successful in the workplace. Specifically of interest to the information systems field is that any newly trained IS professional has to be equipped to solve increasingly difficult problems with great confidence and competence. In this paper we present the case for IS curriculum implementations (Landry 2008) based on the transformational learner centered methodologies (Saulnier 2008). With this approach, student learners take responsibility for their education and are accountable for the outcomes based on a continuous feedback and self adjustment of goal. We present a methodology for learner centered outcome development by using a template approach developed within a quality process improvement environment. This approach utilizes an existing model curriculum in developing the learner centered attributes. Examples for implementing the approach utilizing team based behaviors are provided

    Effect of Reducing Atmosphere on the Magnetism of Zn1-xCoxO Nanoparticles

    Full text link
    We report the crystal structure and magnetic properties of Zn1-xCoxO nanoparticles synthesized by heating metal acetates in organic solvent. The nanoparticles were crystallized in wurtzite ZnO structure after annealing in air and in a forming gas (Ar95%+H5%). The X-ray diffraction and X-ray photoemission spectroscopy (XPS) data for different Co content show clear evidence for the Co+2 ions in tetrahedral symmetry, indicating the substitution of Co+2 in ZnO lattice. However samples with x=0.08 and higher cobalt content also indicate the presence of Co metal clusters. Only those samples annealed in the reducing atmosphere of the forming gas, and that showed the presence of oxygen vacancies, exhibited ferromagnetism at room temperature. The air annealed samples remained non-magnetic down to 77K. The essential ingredient in achieving room temperature ferromagnetism in these Zn1-xCoxO nanoparticles was found to be the presence of additional carriers generated by the presence of the oxygen vacancies.Comment: 11 pages, 6 figures, submitted to Nanotechnology IO

    Two-dimensional turbulence in magnetised plasmas

    Full text link
    In an inhomogeneous magnetised plasma the transport of energy and particles perpendicular to the magnetic field is in general mainly caused by quasi two-dimensional turbulent fluid mixing. The physics of turbulence and structure formation is of ubiquitous importance to every magnetically confined laboratory plasma for experimental or industrial application. Specifically, high temperature plasmas for fusion energy research are also dominated by the properties of this turbulent transport. Self-organisation of turbulent vortices to mesoscopic structures like zonal flows is related to the formation of transport barriers that can significantly enhance the confinement of a fusion plasma. This subject of great importance in research is rarely touched on in introductory plasma physics or continuum dynamics courses. Here a brief tutorial on 2D fluid and plasma turbulence is presented as an introduction to the field, appropriate for inclusion in undergraduate and graduate courses.Comment: This is an author-created, un-copyedited version of an article published in European Journal of Physics. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The definitive publisher authenticated version is available online at doi: 10.1088/0143-0807/29/5/00

    Nutritional depletion of total mixed rations by red-winged blackbirds and projected impacts on dairy cow performance

    Get PDF
    This Research Communication describes an investigation of the nutritional depletion of total mixed rations (TMR) by pest birds. We hypothesized that species-specific bird depredation of TMR can alter the nutritional composition of the ration and that these changes can negatively impact the performance of dairy cows. Blackbirds selected the high energy fraction of the TMR (i.e., flaked corn) and reduced starch, crude fat and total digestible nutrients during controlled feeding experiments. For Holsteins producing 37·1 kg of milk/d, dairy production modeling illustrated that total required net energy intake (NEI) was 35·8 Mcal/d. For the reference TMR unexposed to blackbirds and the blackbird-consumed TMR, NEI supplied was 41·2 and 37·8 Mcal/d, and the resulting energy balance was 5·4 and 2·0 Mcal/d, respectively. Thus, Holsteins fed the reference and blackbird-consumed TMR were estimated to gain one body condition score in 96 and 254 d, and experience daily weight change due to reserves of 1·1 and 0·4 kg/d, respectively. We discuss these results in context of an integrated pest management program for mitigating the depredation caused by pest birds at commercial dairies
    corecore