519 research outputs found

    Assessing Hydrological Response to Changing Climate in the Krishna Basin of India

    Get PDF
    Impact of climate change on water balance components in the Krishna river basin are investigated using a semidistributed hydrological model namely Soil and Water Assessment Tool (SWAT). The model is calibrated and validated using the measured stream flow and meteorological data for the period (1970-1990) at a single guage outlet. The model has been used further for hydrologic parameter simulations. Daily climate simulations from regional climate model PRECIS (Providing Regional Climates for Impacts Studies) is used as input for running SWAT and monthly hydrologic parameters such as precipitation, surface flow, water yield, Evapotranspiration (ET) and Potential Evapotranspiration (PET) are generated under the assumption of no change in Land Use and Land Cover (LULC) pattern over time. Simulations at 23 sub-basins of the Krishna basin have been obtained for the control runs (1961-1990) and the for two time slices of future scenarios (2011-2040) and (2041-2070). Model projections indicate increase in the annual discharge, surface runoff and base flow in the basin in mid-century

    Classical orbital paramagnetism in non-equilibrium steady state

    Full text link
    We report the results of our numerical simulation of classical-dissipative dynamics of a charged particle subjected to a non-markovian stochastic forcing. We find that the system develops a steady-state orbital magnetic moment in the presence of a static magnetic field. Very significantly, the sign of the orbital magnetic moment turns out to be {\it paramagnetic} for our choice of parameters, varied over a wide range. This is shown specifically for the case of classical dynamics driven by a Kubo-Anderson type non-markovian noise. Natural spatial boundary condition was imposed through (1) a soft (harmonic) confining potential, and (2) a hard potential, approximating a reflecting wall. There was no noticeable qualitative difference. What appears to be crucial to the orbital magnetic effect noticed here is the non-markovian property of the driving noise chosen. Experimental realization of this effect on the laboratory scale, and its possible implications are briefly discussed. We would like to emphasize that the above steady-state classical orbital paramagnetic moment complements, rather than contradicts the Bohr-van Leeuwen (BvL) theorem on the absence of classical orbital diamagnetism in thermodynamic equilibrium.Comment: 6 pages, 4 figures, Has appeared in Journal of Astrophysics and Astronomy special issue on 'Physics of Neutron Stars and Related Objects', celebrating the 75th birth-year of G. Srinivasa

    Engineering Art Galleries

    Full text link
    The Art Gallery Problem is one of the most well-known problems in Computational Geometry, with a rich history in the study of algorithms, complexity, and variants. Recently there has been a surge in experimental work on the problem. In this survey, we describe this work, show the chronology of developments, and compare current algorithms, including two unpublished versions, in an exhaustive experiment. Furthermore, we show what core algorithmic ingredients have led to recent successes

    Inhibition of HSV-1 by chemoattracted neutrophils: supernatants of corneal epithelial cells (HCE) and macrophages (THP-1) treated with virus components chemoattract neutrophils (PMN), and supernatants of PMN treated with these conditioned media inhibit viral growth

    Get PDF
    The role of PMNs (neutrophils) in corneal herpes was studied using an in vitro system. Human corneal cells (HCE) and macrophages (THP-1) infected with HSV-1 or treated with virus components (DNA or virus immune complexes) released chemokines, which attracted PMNs. Highly reactive oxygen species were detected in PMNs. PMNs inhibited HSV when overlaid onto infected HCE cells (50:1). PMNs incubated with the supernatants of HCE cells treated with virus components released H2O2 and myeloperoxidase. These inhibited virus growth. PMNs released NO and MIG, which may differentiate CD4 T cells to Th1. PMNs participate in innate immune responses, limit virus growth, and initiate immunopathology

    The association between histamine 2 receptor antagonist use and Clostridium difficile infection: a systematic review and meta-analysis.

    Get PDF
    Background Clostridium difficile infection (CDI) is a major health problem. Epidemiological evidence suggests that there is an association between acid suppression therapy and development of CDI. Purpose We sought to systematically review the literature that examined the association between histamine 2 receptor antagonists (H2RAs) and CDI. Data source We searched Medline, Current Contents, Embase, ISI Web of Science and Elsevier Scopus from 1990 to 2012 for all analytical studies that examined the association between H2RAs and CDI. Study selection Two authors independently reviewed the studies for eligibility. Data extraction Data about studies characteristics, adjusted effect estimates and quality were extracted. Data synthesis Thirty-five observations from 33 eligible studies that included 201834 participants were analyzed. Studies were performed in 6 countries and nine of them were multicenter. Most studies did not specify the type or duration of H2RAs therapy. The pooled effect estimate was 1.44, 95% CI (1.22–1.7), I2 = 70.5%. This association was consistent across different subgroups (by study design and country) and there was no evidence of publication bias. The pooled effect estimate for high quality studies was 1.39 (1.15–1.68), I2 = 72.3%. Meta-regression analysis of 10 study-level variables did not identify sources of heterogeneity. In a speculative analysis, the number needed to harm (NNH) with H2RAs at 14 days after hospital admission in patients receiving antibiotics or not was 58, 95% CI (37, 115) and 425, 95% CI (267, 848), respectively. For the general population, the NNH at 1 year was 4549, 95% CI (2860, 9097). Conclusion In this rigorous systematic review and meta-analysis, we observed an association between H2RAs and CDI. The absolute risk of CDI associated with H2RAs is highest in hospitalized patients receiving antibiotics

    Fe and N self-diffusion in amorphous FeN: A SIMS and neutron reflectivity study

    Full text link
    Simultaneous measurement of self-diffusion of iron and nitrogen in amorphous iron nitride (Fe86N14) using secondary ion mass spectroscopy (SIMS) technique has been done. In addition neutron reflectivity (NR) technique was employed to study the Fe diffusion in the same compound. The broadening of a tracer layer of 57Fe8615N14 sandwiched between Fe86N14 layers was observed after isothermal vacuum annealing of the films at different temperatures in SIMS measurements. And a decay of the Bragg peak intensity after isothermal annealing was observed in [Fe86N14/57Fe86N14]10 multilayers in NR. Strong structural relaxation of diffusion coefficient was observed below the crystallization temperature of the amorphous phase in both measurements. It was observed from the SIMS measurements that Fe diffusion was about 2 orders of magnitude smaller compared to nitrogen at a given temperature. The NR measurements reveal that the mechanism of Fe self-diffusion is very similar to that in metal-metal type metallic glasses. The structural relaxation time for Fe and N diffusion was found comparable indicating that the obtained relaxation time essentially pertain to the structural relaxation of the amorphous phase.Comment: 10 pages 12 figure

    Synthesis and Characterization of Tin Disulfide (SnS2) Nanowires

    Get PDF
    The ordered tin disulfide (SnS2) nanowire arrays were first fabricated by sulfurizing the Sn nanowires, which are embedded in the nanochannels of anodic aluminum oxide (AAO) template. SnS2nanowire arrays are highly ordered and highly dense. X-ray diffraction (XRD) and corresponding selected area electron diffraction (SAED) patterns demonstrate the SnS2nanowire is hexagonal polycrystalline. The study of UV/Visible/NIR absorption shows the SnS2nanowire is a wide-band semiconductor with three band gap energies (3.3, 4.4, and 5.8 eV)
    corecore