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Soil quality assessment for desertification based on multi-indicators with the best-worst method in a semi-arid ecosystem

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Journal of Arid Land 2023年第7期15卷 779-796页

作者： Orhan DENGİZ İnci DEMİraĞTUraN Department of Soil Science and Plant Nutrition Faculty of AgricultureOndokuz Mayıs UniversitySamsun-55139Turkey Department of Geography Faculty of EconomicAdministrative and Social SciencesSamsun UniversitySamsun-55030Turkey

Since there are some signs of land degradation and desertification showing how soil sustainability is threatened, it is crucial to create a soil quality index(SQI) model in the semi-arid ?orum Basin, situated between the Black Sea and Anatolia Region, Central Turkey. The primary aims of the study are:(1) to determine SQI values of the micro-basin in terms of land degradation and ***, the best-worst method(BWM) was used to determine the weighting score for each parameter;(2) to produce the soils' spatial distribution by utilizing different geostatistical models and GIS(geographic information system) techniques;and(3) to validate the obtained SQI values with biomass reflectance values. Therefore, the relationship of RE-OSAVI(red-edge optimized soil-adjusted vegetation index) and NDVI(normalized difference vegetation index) generated from Sentinel-2A satellite images at different time series with soil quality was examined. Results showed that SQI values were high in the areas that had almost a flat and slight slope. Moreover, the areas with high clay content and thick soil depth did not have salinity problems, and were generally distributed in the middle parts of the basin. However, the areas with a high slope, poor vegetation, high sand content, and low water holding capacity had low SQI ***, a statistically high positive correlation of RE-OSAVI and NDVI indices with soil quality was found, and NDVI had the highest correlative value for June(R~2=0.802) compared with RE-OSAVI.

关键词： soil quality land degradation desertification best-worst method remote sensing

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A new view of the local Universe

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 167-168页

作者： Lister Staveley-smith International Centre for radio Astronomy Research(ICraR) University of Western AustraliaCrawley WA 6009Australia ARC Centre of Excellence for All Sky Astrophysics(ASTRO 3D) Crawley WA 6009Australia

The distribution and kinematics of gas in and around dark matter halos, the formation of stellar populations from the gravitational collapse of gas clouds, and the interaction of stars and their remnants with interste... 详细信息

关键词： galaxies stars galactic

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Inherent Complexities of a Multi-stakeholder Approach to Building Community Resilience

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International Journal of Disaster Risk Science 2020年第1期11卷 32-45页

作者： Josephine Adekola Denis Fischabcher-smith Moira Fischabcher-smith Finance Accounting and RiskGlasgow Caledonian UniversityGlasgow G40BAScotlandUK College of Social Sciences University of GlasgowGlasgow G128QQScotlandUK

Enhancing community resilience has increasingly involved national and regional governments adopting a multi-stakeholder approach because of the potential interagency benefits. This has led to questions about how best to involve stakeholder groups in translating community resilience policies into practice. This exploratory study contributes to this discussion by addressing two key areas that are fundamental in the concerted effort to build community resilience to natural hazards:(1) stakeholder understanding of community resilience as a concept;and(2) the difficulties associated with the processes of risk assessment and preparedness that stakeholders face locally in building community resilience. Data were collected through semistructured interviews with 25 practitioners and experts within Scotland’s resilience community, and were analyzed through an inductive approach to thematic analysis. These data show how the interpretation of community resilience differs across stakeholder groups. Analysis of the data reveals challenges around the nature of the risk assessment and its role in shaping risk perception and communication. Significant complications occur in communicating about low probability-high consequence events, perceived territoriality, competing risk prioritizations, and the challenges of managing hazards within a context of limited resources. The implications of these issues for policy and practice are also discussed.

关键词： Community disaster preparedness Community resilience Multi-stakeholder approach Natural hazards Risk assessment

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Phylogenetic reconstruction of Chirita and allies (Gesneriaceae) with taxonomic treatments

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Journal of Systematics and Evolution 2011年第1期49卷 50-64页

作者： James F. smith Department of Biological Sciences Boise State University

Chirita D. Don, a large genus in the subfamily Cyrtandroideae of Gesneriaceae, has been the subject of much debate whether it is a natural group or not. In addition, the highly heterogeneous Chirita has also been very problematic with regard to delimitation and subdivision. Here we used the nrDNA internal transcribed spacer and cpDNA trnL-F for molecular phylogenetic analaysis, combined with morphological data. Our results suggest that Chirita is an artificial, polyphyletic genus. The most important character that defines Chirita, the dorso-ventrally oblique and bilamellar stigma, has evolved convergently in different clades of diandrous Cyrtandroideae. Chirita sensu stricto only includes the species of Chirita sect. Chirita, whereas Chirita sect. Microchirita is an independent clade located at the basal node of the phylogenetic tree. Chirita sect. Liebigia is closely related to Didymocarpus with an entire stigma unlike other species of Chirita. The species of Chirita sect. Gibbosaccus, Chiritopsis, Primulina, and Wentsaiboea form a monophyletic group that is sister to a strongly supported clade comprising four monotypic genera Paralagarosolen, Calcareoboea, Petrocodon, and Tengia. We further analyzed the morphological evolution of Chirita and identified a series of morphological synapomorphies for the monophyletic groups revealed herein, and thereby provide a taxonomic treatment in this study.

关键词： Chirita D. Don morphological evolution phylogenetic reconstruction polyphyly taxonomic treatment.

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Novel Heat Transfer Issues Associated with the Design and Safe Operation of the MEGAPIE Spallation Source Target

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Journal of Thermal Science 2007年第1期16卷 63-78页

作者： Brian L.smith Thermal Hydraulics Laboratory Paul Scherrer InstituteSwitzerland

Critical heat transfer problems are discussed in the context of the operation of a spallation source target, which represents a first demonstration of the feasibility of an innovative concept for generating energy using a particle accelerator. Within the framework of the umbrella project MEGAPIE, an R＆D support group was organized to take responsibility for target cooling. This involved the use of advanced numerical methods - Computational Fluid Dynamics （CFD） and Finite Element Method （FEM） - validated against suitable experimental data, and by means of appropriate benchmarking exercises. The design studies using CFD resulted in an optimum flow configuration being defined for the coolant circulation. Flow visualization tests were undertaken using a glass/water test section, with the velocity field mapped using optical and ultrasonic measuring techniques. These were followed by heat transfer tests, using the actual target materials （lead-bismuth-eutectic coolant and steel confinement）. Further CFD/FEM work to analyze operational transients and accident sequences was also carded out, and is described in the paper.

关键词： computational fluid dynamics finite element method liquid-metal coolant spallation source target

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Stellar structure model in hydrostatic equilibrium in the context of f(R)-gravity

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Research in Astronomy and Astrophysics 2017年第12期17卷 31-40页

作者： raíla Andr Gilberto M.Kremer Departamento de Fisica Universidade Federal do Parana81531-980 CuritibaBrazil Manipal Centre for Natural Sciences Manipal UniversityManipal 576104India

In this work we present a stellar structure model from the f（R）-gravity point of view capable of describing some classes of stars（white dwarfs, brown dwarfs, neutron stars, red giants and the Sun）. This model is based on f（R）-gravity field equations for f（R） = R ＋ f2R2, hydrostatic equilibrium equation and a polytropic equation of state. We compare the results obtained with those found by Newtonian theory. It has been observed that in these systems, where high curvature regimes emerge,stellar structure equations undergo modifications. Despite the simplicity of this model, the results are satisfactory. The estimated values of pressure, density and temperature of the stars are within those determined by observations. This f（R）-gravity model has proved to be necessary to describe stars with strong fields such as white dwarfs, neutron stars and brown dwarfs, while stars with weaker fields, such as red giants and the Sun, are best described by Newtonian theory.

关键词： cosmology:theory stars:general massive brown dwarfs white dwarfs neutron

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Nutritional therapy for active Crohn’s disease

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World Journal of Gastroenterology 2008年第27期14卷 4420-4423页

作者： Paul A smith Specialist Registrar in Gastroenterology North Manchester General Hospital Gastroenterology Department Delaunays Road Crumpsall Manchester

Nutritional therapy for active Crohn’s disease (CD) is an underutilised form of treatment in adult patients, though its use is common in the paediatric population. There is evidence that nutritional therapy can effectively induce remission of CD in adult patients. Enteral nutrition therapy is safe and generally well tolerated. Meta-analysis data suggest that corticosteroids are superior to nutritional treatment for induction of remission in active CD. However, the potential side effects of such pharmacotherapy must be taken into consideration. This review examines the evidence for the efficacy of elemental and polymeric diets, and the use of total parenteral nutrition in active CD.

关键词： Crohn's disease Nutrition Dietary Treatment Steroids

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Periodic Solutions of Evolution Variational Inequalities—a Method of Guiding Functions

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Chinese Annals of Mathematics,Series B 2009年第3期30卷 261-272页

作者： Samir ADLY Daniel GOELEVEN Michel THra Département de Math'ematiques et Informatique Laboratoire XLIM(Unité Mixte 6172 du CNRS)Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. Laboratoire d' Informatique et de Mathématiques Université de La Réunion97400 Saint-DenisFrance.

This paper focuses on a part of the presentation given by the third author at the Shanghai Forum on Industrial and Applied Mathematics(Shanghai 2006).It is related to the existence of a periodic solution of evolution ... 详细信息

关键词： Variational inequality Differential inclusion Topological degree Guiding function Periodic solution

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ROBUST HIGH ORDER CONVERGENCE OF AN OVERLAPPING SCHWARZ METHOD FOR SINGULARLY PERTURBED SEMILINEAR REACTION-DIFFUSION PROBLEMS

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Journal of Computational Mathematics 2013年第5期31卷 509-521页

作者： S. Chandra Sekhara ra~ Sunil Kumar Department of Mathematics Indian Institute of Technology Delhi Hauz khas New Delhi-110016 India

In this article we propose an overlapping Schwarz domain decomposition method for solving a singularly perturbed semilinear reaction-diffusion problem. The solution to this problem exhibits boundary layers of width O（√ε ln（1/√ε）） at both ends of the domain due to the presence of singular perturbation parameter ε. The method splits the domain into three overlapping subdomains, and uses the Numerov or Hermite scheme with a uniform mesh on two boundary layer subdomains and a hybrid scheme with a uniform mesh on the interior subdomain. The numerical approximations obtained from this method are proved to be almost fourth order uniformly convergent （in the maximum norm） with respect to the singular perturbation parameter. Furthermore, it is proved that, for small ε, one iteration is sufficient to achieve almost fourth order uniform convergence. Numerical experiments are given to illustrate the theoretical order of convergence established for the method.

关键词： Singular perturbation Semilinear reaction-diffusion Overlapping Schwarzmethod Robust convergence Numerov scheme.

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Future prospectives for the management of chronic hepatitis B

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World Journal of Gastroenterology 2007年第18期13卷 2554-2567页

作者： WF Leemans HLA Janssen ra de Man Department of Gastroenterology & Hepatology Erasmus MC University Medical Center Rotterdam The Netherlands

Chronic hepatitis B virus infection affects about 400 million people around the globe and causes approximately a million deaths a year. Since the discovery of interferon-α as a therapeutic option the treatment of hepatitis B has evolved fast and management has become increasingly complicated. The amount of viral replication reflected in the viral load （HBV-DNA） plays an important role in the development of cirrhosis and hepatocellular carcinoma. The current treatment modalities for chronic hepatitis B are immunomodulatory （interferons） and antiviral suppressants （nucleoside and nucleotide analogues） all with their own advantages and limitations. An overview of the treatment efficacy for both immunomodulatory as antiviral compounds is provided in order to provide the clinician insight into the factors influencing treatment outcome. With nucleoside or nucleotide analogues suppression of viral replication by 5-7 log10 is feasible, but not all patients respond to therapy. Known factors influencing treatment outcome are viral load, ALT levels and compliance. Many other factors which might influence treatment are scarcely investigated. Identifying the factors associated with response might result in stopping rules, so treatment could be adapted in an early stage to provide adequate treatment and avoid the development of resistance. The efficacy of compounds for the treatment of mutant virus and the cross-resistance is largely unknown. However, genotypic and phenotypic testing as well as small clinical trials provided some data on efficacy in this population. Discontinuation of nucleoside or nucleotide analogues frequently results in viral relapse; however, some patients have a sustained response. Data on the risk factors for relapse are necessary in order to determine when treatment can be discontinued safely. In conclusion： chronic hepatitis B has become a treatable disease; however, much research is needed to tailor therapy to an individual patient, to predict the susta

关键词： Hepatitis B virus Cirrhosis Treatment Interferon Nucleoside analogues Nucleotide analogues Lamivudine Adefovir Entecavir Telbivudine Tenofovir Resistance Genotype

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