1,186 research outputs found

    Customer information systems: Approaching a new field in information systems from a new perspective

    Get PDF
    Recent years have witnessed an increasing awareness and need for information systems that can fulfil a role on the boundary between organisations and their environments. However, these so-called Customer Information Systems (CIS) have been developed using a traditional design approach with an emphasis on information systems that ignores the role of social systems in business decision-making. Consequently, a number of well-known problems concerning the use of information technology have also risen in the CIS area. Therefore, we propose a new design approach to CIS that addresses responsibilities and norms in business decision-making and focuses on the interplay between information systems design and organisational design. We propose extensions of current design issues that - if successful - could be of interest for researchers as well as practitioners

    The Glycemic, Cholesterol, and Weight Effects of L-carnitine in Diabetes: A Systematic Review and Meta-analysis of Randomized Controlled Trials

    Get PDF
    Introduction L-carnitine possibly impacts insulin sensitivity and glucose metabolism. However, its therapeutic role in diabetes is poorly understood. Methods A systematic review and meta-analysis were conducted using PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) from inception through June 30, 2021. Included studies evaluated the use of L-carnitine in diabetes on fasting blood glucose (FBG), hemoglobin A1c (HbA1c), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), weight, or body mass index (BMI). Weighted mean difference (WMD) and 95% confidence intervals (CI) were calculated using the DerSimonian and Laird random-effects model. Results Seventeen studies involving 1622 patients were included. Reductions in FBG (WMD = -0.46 mmol/L, 95% CI = -0.68 to -0.23 mmol/L), HbA1c (WMD = -0.5%, 95% CI = -0.8 to -0.1%), TC (WMD = -0.29 mmol/L, 95% CI = -0.42 to -0.16 mmol/L), and LDL-C (WMD = -0.23 mmol/L, 95% CI = -0.39 to -0.07 mmol/L) were significant. Effects on HDL-C, TG, weight, or BMI were insignificant. Doses between 1001 to 2000 mg showed greatest benefit (p \u3c 0.02 for all). Discussion/Conclusion L-carnitine plays a potential role as adjunctive therapy in diabetes. Additional research is necessary for patients with higher baseline HbA1c and type 1 diabetes

    The groupoidal analogue Theta~ to Joyal's category Theta is a test category

    Full text link
    We introduce the groupoidal analogue \tilde\Theta to Joyal's cell category \Theta and we prove that \tilde\Theta is a strict test category in the sense of Grothendieck. This implies that presheaves on \tilde\Theta model homotopy types in a canonical way. We also prove that the canonical functor from \Theta to \tilde\Theta is aspherical, again in the sense of Grothendieck. This allows us to compare weak equivalences of presheaves on \tilde\Theta to weak equivalences of presheaves on \Theta. Our proofs apply to other categories analogous to \Theta.Comment: 41 pages, v2: references added, Remark 7.3 added, v3: metadata update

    Uranium on uranium collisions at relativistic energies

    Get PDF
    Deformation and orientation effects on compression, elliptic flow and particle production in uranium on uranium collisions (UU) at relativistic energies are studied within the transport model ART. The density compression in tip-tip UU collisions is found to be about 30% higher and lasts approximately 50% longer than in body-body or spherical UU reactions. The body-body UU collisions have the unique feature that the nucleon elliptic flow is the highest in the most central collisions and remain a constant throughout the reaction. We point out that the tip-tip UU collisions are more probable to create the QGP at AGS and SPS energies while the body-body UU collisions are more useful for studying properties of the QGP at higher energies.Comment: 8 pages + 4 figure

    Introduction to Loop Quantum Gravity

    Full text link
    This article is based on the opening lecture at the third quantum geometry and quantum gravity school sponsored by the European Science Foundation and held at Zakopane, Poland in March 2011. The goal of the lecture was to present a broad perspective on loop quantum gravity for young researchers. The first part is addressed to beginning students and the second to young researchers who are already working in quantum gravity.Comment: 30 pages, 2 figures. arXiv admin note: substantial text overlap with arXiv:gr-qc/041005

    Collective modes of asymmetric nuclear matter in Quantum HadroDynamics

    Full text link
    We discuss a fully relativistic Landau Fermi liquid theory based on the Quantum Hadro-Dynamics (QHDQHD) effective field picture of Nuclear Matter ({\it NM}). From the linearized kinetic equations we get the dispersion relations of the propagating collective modes. We focus our attention on the dynamical effects of the interplay between scalar and vector channel contributions. A beautiful ``mirror'' structure in the form of the dynamical response in the isoscalar/isovector degree of freedom is revealed, with a complete parallelism in the role respectively played by the compressibility and the symmetry energy. All that strongly supports the introduction of an explicit coupling to the scalar-isovector channel of the nucleon-nucleon interaction. In particular we study the influence of this coupling (to a δ\delta-meson-like effective field) on the collective response of asymmetric nuclear matter (ANMANM). Interesting contributions are found on the propagation of isovector-like modes at normal density and on an expected smooth transition to isoscalar-like oscillations at high baryon density. Important ``chemical'' effects on the neutron-proton structure of the mode are shown. For dilute ANMANM we have the isospin distillation mechanism of the unstable isoscalar-like oscillations, while at high baryon density we predict an almost pure neutron wave structure of the propagating sounds.Comment: 18 pages (LATEX), 8 Postscript figures, uses "epsfig

    Atomic X-ray Spectroscopy of Accreting Black Holes

    Full text link
    Current astrophysical research suggests that the most persistently luminous objects in the Universe are powered by the flow of matter through accretion disks onto black holes. Accretion disk systems are observed to emit copious radiation across the electromagnetic spectrum, each energy band providing access to rather distinct regimes of physical conditions and geometric scale. X-ray emission probes the innermost regions of the accretion disk, where relativistic effects prevail. While this has been known for decades, it also has been acknowledged that inferring physical conditions in the relativistic regime from the behavior of the X-ray continuum is problematic and not satisfactorily constraining. With the discovery in the 1990s of iron X-ray lines bearing signatures of relativistic distortion came the hope that such emission would more firmly constrain models of disk accretion near black holes, as well as provide observational criteria by which to test general relativity in the strong field limit. Here we provide an introduction to this phenomenon. While the presentation is intended to be primarily tutorial in nature, we aim also to acquaint the reader with trends in current research. To achieve these ends, we present the basic applications of general relativity that pertain to X-ray spectroscopic observations of black hole accretion disk systems, focusing on the Schwarzschild and Kerr solutions to the Einstein field equations. To this we add treatments of the fundamental concepts associated with the theoretical and modeling aspects of accretion disks, as well as relevant topics from observational and theoretical X-ray spectroscopy.Comment: 63 pages, 21 figures, Einstein Centennial Review Article, Canadian Journal of Physics, in pres

    Coronal Diagnostics from Narrowband Images around 30.4 nm

    Full text link
    Images taken in the band centered at 30.4 nm are routinely used to map the radiance of the He II Ly alpha line on the solar disk. That line is one of the strongest, if not the strongest, line in the EUV observed in the solar spectrum, and one of the few lines in that wavelength range providing information on the upper chromosphere or lower transition region. However, when observing the off-limb corona the contribution from the nearby Si XI 30.3 nm line can become significant. In this work we aim at estimating the relative contribution of those two lines in the solar corona around the minimum of solar activity. We combine measurements from CDS taken in August 2008 with temperature and density profiles from semiempirical models of the corona to compute the radiances of the two lines, and of other representative coronal lines (e.g., Mg X 62.5 nm, Si XII 52.1 nm). Considering both diagnosed quantities from line ratios (temperatures and densities) and line radiances in absolute units, we obtain a good overall match between observations and models. We find that the Si XI line dominates the He II line from just above the limb up to ~2 R_Sun in streamers, while its contribution to narrowband imaging in the 30.4 nm band is expected to become smaller, even negligible in the corona beyond ~2 - 3 R_Sun, the precise value being strongly dependent on the coronal temperature profile.Comment: 26 pages, 11 figures; to be published in: Solar Physic

    Employment Changes following Breast Cancer Diagnosis: The Effects of Race and Place

    Get PDF
    The financial implications of breast cancer diagnosis may be greater among rural and black women. Women with incident breast cancer were recruited as part of the Carolina Breast Cancer Study. We compared unadjusted and adjusted prevalence of cancer-related job or income loss, and a composite measure of either outcome, by rural residence and stratified by race. We included 2435 women: 11.7% were rural; 48.5% were black; and 38.0% reported employment changes after diagnosis. Rural women more often reported employment effects, including reduced household income (43.6% vs 35.4%, two-sided ?2 test P =. 04). Rural white, rural black, and urban black women each more often reported income reduction (statistically significant vs. urban white women), although these groups did not meaningfully differ from each other. In multivariable regression, rural differences were mediated by socioeconomic factors, but racial differences remained. Programs and policies to reduce financial toxicity in vulnerable patients should address indirect costs of cancer, including lost wages and employment
    • …
    corecore