633 research outputs found

    Geomorphologic Character & Receding Trend of Kolahoi Glacier in Kashmir Himalaya

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    Glaciers are a valuable source of fresh water which sustain life and provide water for drinking, irrigation, hydro power generation, etc. Besides, these exert considerable influence on the climate of a region and fluctuate in dimension in response to the climatological changes and therefore, these are regarded as sensitive indicators of the climate of a region. Glaciers are in the process of retreat in almost all the parts of the world due to global warming. The same process of retreat is found in the valley’s largest glacier, Kolahoi. Thus, it is of great significance to obtain the accurate information of changes in Kolahoi glacier  (34° 07′ to 34° 12′ N latitude; & 75° 16′ to 75° 23′ E longitude, Liddar valley, Kashmir Himalayas). The study was carried out using Remote Sensing and GIS techniques and thorough field observations were conducted to identify the geomorphologic features. The area of the glacier receded from 13.57km² in 1963 to 10.69km² in 2005, registering a change of 2.88km2at a rate of 0.068km2per year. The Crevasses developed in the ablation portion of the Kolahoi Glacier and the formation of numerous caves at its snout position act as the important indicators of its recession. The result of this retreat will prove disastrous for the valley in many fields like drinking water, agriculture, horticulture, ground water, hydro power capacity of the state, etc. Therefore, we need to make efforts to save this precious source of water for the present as well as for future generations

    Probabilistic Simulation of Multi-Scale Composite Behavior

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    A methodology is developed to computationally assess the non-deterministic composite response at all composite scales (from micro to structural) due to the uncertainties in the constituent (fiber and matrix) properties, in the fabrication process and in structural variables (primitive variables). The methodology is computationally efficient for simulating the probability distributions of composite behavior, such as material properties, laminate and structural responses. Bi-products of the methodology are probabilistic sensitivities of the composite primitive variables. The methodology has been implemented into the computer codes PICAN (Probabilistic Integrated Composite ANalyzer) and IPACS (Integrated Probabilistic Assessment of Composite Structures). The accuracy and efficiency of this methodology are demonstrated by simulating the uncertainties in composite typical laminates and comparing the results with the Monte Carlo simulation method. Available experimental data of composite laminate behavior at all scales fall within the scatters predicted by PICAN. Multi-scaling is extended to simulate probabilistic thermo-mechanical fatigue and to simulate the probabilistic design of a composite redome in order to illustrate its versatility. Results show that probabilistic fatigue can be simulated for different temperature amplitudes and for different cyclic stress magnitudes. Results also show that laminate configurations can be selected to increase the redome reliability by several orders of magnitude without increasing the laminate thickness--a unique feature of structural composites. The old reference denotes that nothing fundamental has been done since that time

    Productivity and economic evaluation of Willow (Salix alba L.) based silvopastoral agroforestry system in Kashmir valley

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    Performance of two fodder crops namely, sorghum (Sorghum vulgare L.) and maize (Zea mays L.) was investigated with Willow (Salix alba L.) to evaluate productivity and economics of the silvopastoral agroforestry system in Kashmir valley. The experiment was laid out by planting two year old willows at 2.0m × 2.0m spacing and dividing the main plot into sub-plots of size 8m × 2m each with 5 replications in randomized block design (RDB). The intercrops of sorghum and maize were maintained at 20cm × 10 cm spacing and supplied with recommended doses of fertilizers. The economics of the willow plantation intercropped with fodder crops was compared with sole willow farming by the benefit-cost ratio and net present worth. The study revealed the differential behaviour of Salix alba regarding growth parameters (height, diameter and girth) by different intercrops and various fodder intercrops with respect to yield, above ground biomass, dry matter production and soil nutrient status (pH, organic carbon, available nitrogen, phosphorus and potassium). The willow based silvopastoral system was estimated to have benefit-cost ratio of 2.71 with maize and 2.68 with sorghum, while as sole crop the willows accrued a benefit-cost ratio of 2.66. The study is useful in discovering growth of willows, productivity of fodder crops and soil nutrient status under various silvopastoral agroforestry systems for maximizing economic gains. The findings envisaged evidences in favour of adopting willow based silvopastoral agroforestry instead of sole tree farming and the knowledge of interactions will be helpful in proper management of the system for sustained multiple productions

    Wilson chains are not thermal reservoirs

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    Wilson chains, based on a logarithmic discretization of a continuous spectrum, are widely used to model an electronic (or bosonic) bath for Kondo spins and other quantum impurities within the numerical renormalization group method and other numerical approaches. In this short note we point out that Wilson chains can not serve as thermal reservoirs as their temperature changes by a number of order Delta E when a finite amount of energy Delta E is added. This proves that for a large class of non-equilibrium problems they cannot be used to predict the long-time behavior.Comment: 2 page

    Density-functional embedding using a plane-wave basis

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    The constrained electron density method of embedding a Kohn-Sham system in a substrate system (first described by P. Cortona, Phys. Rev. B {\bf 44}, 8454 (1991) and T.A. Wesolowski and A. Warshel, J. Phys. Chem {\bf 97}, 8050 (1993)) is applied with a plane-wave basis and both local and non-local pseudopotentials. This method divides the electron density of the system into substrate and embedded electron densities, the sum of which is the electron density of the system of interest. Coupling between the substrate and embedded systems is achieved via approximate kinetic energy functionals. Bulk aluminium is examined as a test case for which there is a strong interaction between the substrate and embedded systems. A number of approximations to the kinetic-energy functional, both semi-local and non-local, are investigated. It is found that Kohn-Sham results can be well reproduced using a non-local kinetic energy functional, with the total energy accurate to better than 0.1 eV per atom and good agreement between the electron densities.Comment: 11 pages, 4 figure

    Antidepressants have complex associations with longitudinal depressive burden in bipolar disorder

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    Aims: Antidepressants are common in bipolar disorder (BD), but controversial due to questionable efficacy/tolerability. We assessed baseline antidepressant use/depression associations in BD. Methods: Stanford BD Clinic outpatients, enrolled during 2000\u20132011, assessed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation, were monitored up to two years with the STEP-BD Clinical Monitoring Form while receiving naturalistic expert treatment. Prevalence/correlates of baseline antidepressant use in recovered (euthymic 658 weeks)/depressed patients were assessed. Kaplan\u2013Meier survival analyses assessed times to depressive recurrence/recovery in patients with/without baseline antidepressant use, and Cox Proportional Hazard regression analyses assessed covariate effects. Results: Baseline antidepressant use was significantly (albeit without Bonferroni multiple comparison correction) less among 105 recovered (31.4%) versus 153 depressed (44.4%) patients, and among recovered patients (again without Bonferroni correction), associated with Caucasian race, earlier onset, worse Clinical Global Impression scores, and hastened depressive recurrence (only if mood elevation episodes were not censored), driven by lifetime anxiety disorder, and more (even with Bonferroni correction) bipolar II disorder, lifetime anxiety and eating disorders, and core psychotropics. Baseline antidepressant use among depressed patients was associated with significantly (again without Bonferroni correction) older age, female gender, and more (even with Bonferroni correction) anxiolytics/hypnotics, complex pharmacotherapy, and core psychotropics, but no other unfavorable illness characteristic/current mood symptom, and not time to depressive recovery. Limitations: Tertiary BD clinic referral sample receiving open naturalistic expert treatment. Analyses without/with Bonferroni correction. Conclusions: Additional research is required to assess the complex associations between baseline antidepressant use and longitudinal depressive burden in BD

    Overcoming challenges to data quality in the ASPREE clinical trial

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    © 2019 The Author(s). Background: Large-scale studies risk generating inaccurate and missing data due to the complexity of data collection. Technology has the potential to improve data quality by providing operational support to data collectors. However, this potential is under-explored in community-based trials. The Aspirin in reducing events in the elderly (ASPREE) trial developed a data suite that was specifically designed to support data collectors: the ASPREE Web Accessible Relational Database (AWARD). This paper describes AWARD and the impact of system design on data quality. Methods: AWARD's operational requirements, conceptual design, key challenges and design solutions for data quality are presented. Impact of design features is assessed through comparison of baseline data collected prior to implementation of key functionality (n = 1000) with data collected post implementation (n = 18,114). Overall data quality is assessed according to data category. Results: At baseline, implementation of user-driven functionality reduced staff error (from 0.3% to 0.01%), out-of-range data entry (from 0.14% to 0.04%) and protocol deviations (from 0.4% to 0.08%). In the longitudinal data set, which contained more than 39 million data values collected within AWARD, 96.6% of data values were entered within specified query range or found to be accurate upon querying. The remaining data were missing (3.4%). Participant non-attendance at scheduled study activity was the most common cause of missing data. Costs associated with cleaning data in ASPREE were lower than expected compared with reports from other trials. Conclusions: Clinical trials undertake complex operational activity in order to collect data, but technology rarely provides sufficient support. We find the AWARD suite provides proof of principle that designing technology to support data collectors can mitigate known causes of poor data quality and produce higher-quality data. Health information technology (IT) products that support the conduct of scheduled activity in addition to traditional data entry will enhance community-based clinical trials. A standardised framework for reporting data quality would aid comparisons across clinical trials

    Differential core pharmacotherapy in bipolar I versus bipolar II disorder and European versus American patients not in a syndromal episode

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    Assess bipolar disorder subtype and treatment location effects on bipolar disorder core pharmacotherapy. Outpatients not in a syndromal episode referred to the University of Milan and Stanford University Bipolar Disorder Clinics were assessed with SCID for the fourth Edition of the Diagnostic and Statistical Manual of Mood Disorders, and the Systematic Treatment Enhancement Program for Bipolar Disorder Affective Disorders Evaluation, respectively. Prevalence and clinical correlates of antidepressant, antipsychotic, and mood stabilizer use, in aggregate and individually, were compared in bipolar I (BDI) versus II (BDII) patients in Milan/Stanford and in Milan versus Stanford patients, stratified by subtype. Milan/Stanford pooled BDI versus BDII patients significantly more often took antipsychotic (69.8 versus 44.8%), mood stabilizers (68.6 versus 57.7%), and valproate (40.1 versus 17.5%), and less often took antidepressants (23.1 versus 55.6%) and lamotrigine (9.9 versus 25.2%). Milan versus Stanford patients (stratified by bipolar disorder subtype) significantly more often took antipsychotic (BDI and BDII), antidepressants (BDII), and valproate (BDII), and less often took lamotrigine (BDI). Research regarding bipolar disorder core pharmacotherapy relationships with bipolar subtype and treatment location is warranted to enhance clinical management

    A diversity of patterns to new (3 + 1)-dimensional hirota bilinear equation that models dynamics of waves in fluids

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    DATA AVAILABITY STATEMENT: Data will be made available on request.This article discusses the behavior of specific dispersive waves to new (3+1)-dimensional Hirota bilinear equation (3D-HBE). The 3D-HBE is used as a governing equation for the propagation of waves in fluid dynamics. The Hirota bilinear method (HBM) is successfully applied together with various test strategies for securing a class of results in the forms of lump-periodic, breather-type, and two-wave solutions. Solitons for nonlinear partial differential equations (NLPDEs) can be identified via the well-known mathematical methodology known as the Hirota method. However, this requires for bilinearization of nonlinear PDEs. The method employed provides a comprehensive explanation of NLPDEs by extracting and also generating innovative exact solutions by merging the outcomes of various procedures. To further illustrate the impact of the parameters, we also include a few numerical visualizations of the results. These findings validate the usefulness of the used method in improving the nonlinear dynamical behavior of selected systems. These results are used to illustrate the physical properties of lump solutions and the collision-related components of various nonlinear physical processes. The outcomes demonstrate the efficiency, rapidity, simplicity, and adaptability of the applied algorithm.http://www.elsevier.com/locate/rinpMechanical and Aeronautical EngineeringSDG-09: Industry, innovation and infrastructur

    Recalibration of the limiting antigen avidity EIA to determine mean duration of recent infection in divergent HIV-1 subtypes.

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    ArticleBackground: Mean duration of recent infection (MDRI) and misclassification of long-term HIV-1 infections, as proportion false recent (PFR), are critical parameters for laboratory-based assays for estimating HIV-1 incidence. Recent review of the data by us and others indicated that MDRI of LAg-Avidity EIA estimated previously required recalibration. We present here results of recalibration efforts using >250 seroconversion panels and multiple statistical methods to ensure accuracy and consensus. Methods: A total of 2737 longitudinal specimens collected from 259 seroconverting individuals infected with diverse HIV-1 subtypes were tested with the LAg-Avidity EIA as previously described. Data were analyzed for determination of MDRI at ODn cutoffs of 1.0 to 2.0 using 7 statistical approaches and sub-analyzed by HIV-1 subtypes. In addition, 3740 specimens from individuals with infection >1 year, including 488 from patients with AIDS, were tested for PFR at varying cutoffs. Results: Using different statistical methods,MDRI values ranged from 88-94 days at cutoff ODn = 1.0 to 177-183 days at ODn = 2.0. The MDRI values were similar by different methods suggesting coherence of different approaches. Testing formisclassification among long-terminfections indicated that overall PFRs were 0.6%to 2.5%at increasing cutoffs of 1.0 to 2.0, respectively. Balancing the need for a longer MDRI and smaller PFR (<2.0%) suggests that a cutoff ODn = 1.5, corresponding to an MDRI of 130 days should be used for cross-sectional application. The MDRI varied among subtypes from 109 days (subtype A&D) to 152 days (subtype C). Conclusions: Based on the new data and revised analysis, we recommend an ODn cutoff = 1.5 to classify recent and long-term infections, corresponding to an MDRI of 130 days (118-142). Determination of revised parameters for estimation of HIV-1 incidence should facilitate application of the LAg-Avidity EIA for worldwide use.This research has been supported by the President’s Emergency Plan for AIDS Relief (PEPFAR) through the Centers for Disease Control and Prevention (CDC)
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