1,220 research outputs found

    Institutional context: What elements shape how community occupational therapists think about their clientsā€™ care?

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    Abstract : Clinical reasoning (CR) is the cognitive process that therapists use to plan, direct, perform and reflect on client care. Linked to intervention efficiency and quality, CR is a core competency that occurs within an institutional context (legal, regulatory, administrative and organisational elements). Because this context can shape how community therapists think about their clientsā€™ care, its involvement in their CR could have a major impact on the interventions delivered. However, little is known about this involvement. Our study thus aimed to describe the elements of the institutional context involved in community therapistsā€™ CR. From March 2012 to June 2014, we conducted an institutional ethnography (IE) inquiry in three Health and Social Services Centres in QuĆ©bec (Canada). We observed participants and conducted semi-structured interviews with 10 occupational therapists. We also interviewed 12 secondary key informants (colleagues and managers) and collected administrative documents (n = 50). We analysed data using the IE process. Of the 13 elements of the institutional context identified, we found that four are almost constantly involved in participantsā€™ CR. These four elements, that is, institutional procedures, organisation's basket of services, occupational therapistsā€™ mandate and wait times for their services, restrictively shape CR. Specifically, occupational therapists restrict their representation of the client's situation and exploration of potential solutions to what is possible within the bounds of these four elements. In light of such restrictions on the way they think about their clientsā€™ care, therapists should pay close attention to the elements of their own institutional context and how they are involved in their CR. Because of its potentially important impact on the future of professions (e.g. further restrictions on professionalsā€™ role, reduced contribution to population health and well-being), this involvement of the institutional context in CR concerns all professionals, be they clinicians, educators, researchers or regulatory college officers

    Helicity sensitive terahertz radiation detection by dual-grating-gate high electron mobility transistors

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    We report on the observation of a radiation helicity sensitive photocurrent excited by terahertz (THz) radiation in dual-grating-gate (DGG) InAlAs/InGaAs/InAlAs/InP high electron mobility transistors (HEMT). For a circular polarization the current measured between source and drain contacts changes its sign with the inversion of the radiation helicity. For elliptically polarized radiation the total current is described by superposition of the Stokes parameters with different weights. Moreover, by variation of gate voltages applied to individual gratings the photocurrent can be defined either by the Stokes parameter defining the radiation helicity or those for linear polarization. We show that artificial non-centrosymmetric microperiodic structures with a two-dimensional electron system excited by THz radiation exhibit a dc photocurrent caused by the combined action of a spatially periodic in-plane potential and spatially modulated light. The results provide a proof of principle for the application of DGG HEMT for all-electric detection of the radiation's polarization state.Comment: 7 pages, 4 figure

    Poultry management : for 4-H poultry projects

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    November, 1952."University of Missouri College of Agriculture and the United States Department of Agriculture Cooperating"--Page 47.Title from caption

    Arnol'd Tongues and Quantum Accelerator Modes

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    The stable periodic orbits of an area-preserving map on the 2-torus, which is formally a variant of the Standard Map, have been shown to explain the quantum accelerator modes that were discovered in experiments with laser-cooled atoms. We show that their parametric dependence exhibits Arnol'd-like tongues and perform a perturbative analysis of such structures. We thus explain the arithmetical organisation of the accelerator modes and discuss experimental implications thereof.Comment: 20 pages, 6 encapsulated postscript figure

    IFN-Ī³ receptor and STAT1 signaling in B cells are central to spontaneous germinal center formation and autoimmunity.

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    Spontaneously developed germinal centers (GCs [Spt-GCs]) harbor autoreactive B cells that generate somatically mutated and class-switched pathogenic autoantibodies (auto-Abs) to promote autoimmunity. However, the mechanisms that regulate Spt-GC development are not clear. In this study, we report that B cell-intrinsic IFN-Ī³ receptor (IFN-Ī³R) and STAT1 signaling are required for Spt-GC and follicular T helper cell (Tfh cell) development. We further demonstrate that IFN-Ī³R and STAT1 signaling control Spt-GC and Tfh cell formation by driving T-bet expression and IFN-Ī³ production by B cells. Global or B cell-specific IFN-Ī³R deficiency in autoimmune B6.Sle1b mice leads to significantly reduced Spt-GC and Tfh cell responses, resulting in diminished antinuclear Ab reactivity and IgG2c and IgG2b auto-Ab titers compared with B6.Sle1b mice. Additionally, we observed that the proliferation and differentiation of DNA-reactive B cells into a GC B cell phenotype require B cell-intrinsic IFN-Ī³R signaling, suggesting that IFN-Ī³R signaling regulates GC B cell tolerance to nuclear self-antigens. The IFN-Ī³R deficiency, however, does not affect GC, Tfh cell, or Ab responses against T cell-dependent foreign antigens, indicating that IFN-Ī³R signaling regulates autoimmune, but not the foreign antigen-driven, GC and Tfh cell responses. Together, our data define a novel B cell-intrinsic IFN-Ī³R signaling pathway specific to Spt-GC development and autoimmunity. This novel pathway can be targeted for future pharmacological intervention to treat systemic lupus erythematosus

    Decoherence and thermalization dynamics of a quantum oscillator

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    We introduce the quantitative measures characterizing the rates of decoherence and thermalization of quantum systems. We study the time evolution of these measures in the case of a quantum harmonic oscillator whose relaxation is described in the framework of the standard master equation, for various initial states (coherent, `cat', squeezed and number). We establish the conditions under which the true decoherence measure can be approximated by the linear entropy 1āˆ’TrĻ^21-{Tr}\hat\rho^2. We show that at low temperatures and for highly excited initial states the decoherence process consists of three distinct stages with quite different time scales. In particular, the `cat' states preserve 50% of the initial coherence for a long time interval which increases logarithmically with increase of the initial energy.Comment: 24 pages, LaTex, 8 ps figures, accepted for publication in J. Opt.

    Propanil Exposure Induces Delayed but Sustained Abrogation of Cell-Mediated Immunity through Direct Interference with Cytotoxic T-Lymphocyte Effectors

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    The postemergent herbicide propanil (PRN; also known as 3,4-dichloropropionanilide) is used on rice and wheat crops and has well-known immunotoxic effects on various compartments of the immune system, including T-helper lymphocytes, B lymphocytes, and macrophages. It is unclear, however, whether PRN also adversely affects cytotoxic T lymphocytes (CTLs), the primary (1Ā°) effectors of cell-mediated immunity. In this study we examined both the direct and indirect effects of PRN exposure on CTL activation and effector cell function to gauge its likely impact on cell-mediated immunity. Initial experiments addressed whether PRN alters the class I major histocompatibility complex (MHC) pathway for antigen processing and presentation by antigen-presenting cells (APCs), thereby indirectly affecting effector function. These experiments demonstrated that PRN does not impair the activation of CTLs by PRN-treated APCs. Subsequent experiments addressed whether PRN treatment of CTLs directly inhibits their activation and revealed that 1Ā° alloreactive CTLs exposed to PRN are unimpaired in their proliferative response and only marginally inhibited in their lytic activity. Surprisingly, secondary stimulation of these alloreactive CTL effectors, however, even in the absence of further PRN exposure, resulted in complete abrogation of CTL lytic function and a delayed but significant long-term effect on CTL responsiveness. These findings may have important implications for the diagnosis and clinical management of anomalies of cell-mediated immunity resulting from environmental exposure to various herbicides and other pesticides

    Socio-eco-evolutionary dynamics in cities

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    Cities are uniquely complex systems regulated by interactions and feedbacks between nature and human society. Characteristics of human society-including culture, economics, technology and politics-underlie social patterns and activity, creating a heterogeneous environment that can influence and be influenced by both ecological and evolutionary processes. Increasing research on urban ecology and evolutionary biology has coincided with growing interest in eco-evolutionary dynamics, which encompasses the interactions and reciprocal feedbacks between evolution and ecology. Research on both urban evolutionary biology and eco-evolutionary dynamics frequently focuses on contemporary evolution of species that have potentially substantial ecological-and even social-significance. Still, little work fully integrates urban evolutionary biology and eco-evolutionary dynamics, and rarely do researchers in either of these fields fully consider the role of human social patterns and processes. Because cities are fundamentally regulated by human activities, are inherently interconnected and are frequently undergoing social and economic transformation, they represent an opportunity for ecologists and evolutionary biologists to study urban "socio-eco-evolutionary dynamics." Through this new framework, we encourage researchers of urban ecology and evolution to fully integrate human social drivers and feedbacks to increase understanding and conservation of ecosystems, their functions and their contributions to people within and outside cities
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