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Evaluating methods to quantify sediment volumes trapped behind check dams,Saldana badlands(Spain)

International Journal of Sediment Research 2017年第1期32卷 1-11页

作者： Iván Ramos-diez Joaquín Navarro-Hevia Roberto San Martín Fernández virginia díaz-gutiérrez Jorge Mongil-Manso department of Agricultural and Forestry Engineering University of Valladolid Sustainable Forest Management Research Institute department of Statistics and Operations Research.University of Valladolid Hydrology and Conservation Research Group.Catholic University of vila

The determination of sediment yield in catchments based on the sediment trapped by check dams is becoming a subject of *** fact,several methods have been developed in recent years to estimate the sediment retained by check *** complexity,precision and accuracy of each method vary *** this study,we evaluate the sediment trapped by check dams comparing the Sections method respect to the Prism,Pyramid,dTMs and Trapezoid *** analyzed a sample of 25 check dams(α-1=90%;ε=10%) in the Saldana badlands(Spain).The results showed that the Sections method offered a volume of retained sediment between the others,which gave an absolute variation from 22%to40%.The high variability of the check dam and sediment wedge sizes made necessary to compare methods in groups combining both *** significant differences in sediment volumes could be found between the methods for very small(height(h):1.8-2.3 m;trapped volume(V):6-102 m3) or large check dams(h > 2.3 m;V:165-387 m3),while significant differences are found for small(h ddle-sized check dams(h:2.2-3.2 m;V:65-235 m3).Nevertheless,volume differences between groups ranged up to + 25%.For these reason,the size of the check dam,the shape of the sediment wedge and the accuracy of the measure methods must considered when selecting an appropriate method to obtain the volume of retained sediment by check dams.A correct estimation of the sediment retention is needed to evaluate the role and efficiency of check dams in restoration projects or to estimate sediment yields.

关键词： Erosion Gullies Check dam construction Sediment retention Erosion models Topographic survey

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Macroinvertebrate　assemblages　of　surface　mine　wetlands　of　Southwest　virginia，USA

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Journal of Environmental Sciences 1996年第1期8卷 1-14页

作者： david H.Jones Robert B. Atkinson John Cairns,Jr.(department of Biology,virginia Polytechnic Institute and State University, Blacksburg,virginia 24061 USA) dept Biol Virginia Poly Inst Blacksburg VA 24061 United States

The focus of this study was to investigate the macroinvertebrate community in surface mine wetlands. Nine wetlands were sampled for macroinvertebrates from July 1993 through May *** sites represented a range of physical,chemical, and biological parameters. Macroinvertebrates were found in all sites;a total of 14 orders, 40 families,and 70 genera were identified in the samples. Insects were the most common invertebrates,and most functional feeding groups were represented. Predators dominated with 63% of the taxa, followed by the collector/gathers with 20%,shredders 14%, and scrapers 3%. Sites differed in the number of taxa inhabiting *** ranged from 10 genera to *** lowest richness was found in two seasonal wetlands that were dry for the majority of the year. A permanently flooded site with no water quality problems and a dense growth of aquatic plants had the highest richness.

关键词： macroinvertebrate assemblages surface mine wetlands wetland faunas.

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Subclinical carotid atherosclerosis predicts all-cause mortality and cardiovascular events in obese patients with negative exercise echocardiography

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World Journal of Cardiology 2019年第1期11卷 24-36页

作者： Rafael Vidal-Perez Raúl Franco-gutiérrez Alberto J Pérez-Pérez virginia Franco-gutiérrez Alberto Gascón-Vázquez Andrea López-López Ana María Testa-Fernández Carlos González-Juanatey department of Cardiology Hospital Universitario Lucus Augusti department of Otolaryngology Hospital Carmen y Severo Ochoa Faculty of Medicine University of Santiago de Compostela

BACKGROUNd Obesity is a major health problem due to its high prevalence. The relationship between obesity and cardiovascular disease is unclear. Some studies agree that certain conditions associated with obesity, such as physical inactivity or cardiovascular risk factors, are responsible for cardiovascular risk excess among obese people. Carotid intima-media thickness and carotid plaques(CP) have been associated with cardiovascular adverse events in healthy populations, and recent data suggest a higher prevalence of subclinical carotid atherosclerosis in obese and metabolically unhealthy patients. However, there are no studies correlating subclinical atherosclerosis and adverse events(AE) in obese *** To determine the association between carotid disease and AE in obese patients with negative exercise echocardiography(EE).METHOdS From January 1, 2006 to december 31, 2010, 2000 consecutive patients with a suspicion of coronary artery disease were submitted for EE and carotid ultrasonography. Exclusion criteria included previous vascular disease, left ventricular ejection fraction disease and inferior to submaximal EE. An AE was defined as all-cause mortality,myocardial infarction and cerebrovascular accident. Subclinical atherosclerosis was defined as CP presence according to Manheim and the American Society of Echocardiography *** Of the 652 patients who fulfilled the inclusion criteria, 226(34.7%) had body mass indexes ≥ 30 kg/m2, and 76 of them(33.6%) had CP. during a mean follow-up time of 8.2(2.1) years, 27 AE were found(11.9%). Mean event-free survival at 1, 5 and 10 years was 99.1%(0.6), 95.1%(1.4) and 86.5%(2.7), respectively. In univariate analysis, CP predicted AE [hazard ratio(HR) 2.52, 95% confidence interval(CI) 1.17-5.46; P = 0.019]. In multivariable analysis, the presence of CP remained a predictor of AE(HR 2.26, 95%CI 1.04-4.95, P = 0.041). Other predictors identified were glomerular

关键词： Carotid intima media thickness Carotid plaque Carotid disease Myocardial infarction Mortality Stroke Exercise stress echocardiography

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Perverse incentives and perverse publishing practices

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Science Bulletin 2015年第14期60卷 1225-1226页

作者： virginia Barbour Committee on Publication Ethics (COPE)

Over the past few years,publishing has becoming increasingly complex with new journals and business models,new technology,new models of peer review and new ways to collaborate and disseminate *** this,the pressure on academics to publish has become increasingly *** have always been the currency of academia—the key to tenure,grant renewal and ***,however,it is

关键词：出版物行为反常货币价值商业模式学术界

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domestic reptiles as source of zoonotic bacteria:a mini review

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Asian Pacific Journal of Tropical Medicine 2017年第8期10卷 789-794页

作者： Valentina virginia Ebani department of Veterinary Science University of PisaI 56124 PisaItaly

Captive reptiles, always more often present in domestic environment as pets, may harbor and excrete a large variety of zoonotic pathogens. Among them, Salmonella is the most wellknown agent, whereas there are very scant data about infections by mycobacteria, chlamydiae and leptospirae in cold-blooded animals. However, the investigations that found antibody reactions and/or the bacteria in samples collected from free-ranging and captive reptiles show that herpetofauna may be involved in the epidemiology of these infections. The present review reports the updated knowledge about salmonellosis, mycobacteriosis, chlamydiosis and leptospirosis in reptiles and underlines the risk of infection to which people, mainly children, are exposed.

关键词： Reptiles Zoonosis Salmonellosis Mycobacteriosis Chlamydiosis Leptospirosis

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TiO<sub>2</sub>Films Synthesis over Polypropylene by Sol-Gel Assisted with Hydrothermal Treatment for the Photocatalytic Propane degradation

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Green and Sustainable Chemistry 2014年第3期4卷 120-132页

作者： Vanessa Guzmán-Velderrain Yudith Ortega López Jesús Salinas gutiérrez Alejandro López Ortiz virginia H. Collins-Martínez Centro de Investigación en Materiales Avanzados S. C. Laboratorio Nacional de Nanotecnología Depto. de Materiales Nanoestructurados Chihuahua México

The present investigation shows experimental results obtained with TiO2 thin films synthesized by the sol-gel method assisted with hydrothermal treatment over polypropylene, using the dip coating technique. Obtained coatings were characterized through SEM, XRd, UV-Vis and the photo- catalytic activity was monitored by GC. According to results, the hydrothermal treatment facilitates the crystallization of the TiO2 anatase phase, which is present in all synthesized films. Crystal size formed from precursor solutions (estimated by the Scherrer’s equation) depends on the time and temperature of the hydrothermal treatment, wherein solution exposed to a higher temperature treatment of 150。C for 1.5 h (H150/1.5) exhibited a larger crystal size compared to those synthesized at 80。C for 1.5 h and 3 h (H80/1.5 and H80/3). Sample H150/1.5 over polypropylene resulted in a uniform and crack free coating. This behavior was attributed to the precursor solution being denser than those synthesized at 80。C. Additionally, the photocatalytic activity of the coatings was evaluated through the degradation of propane. Coating H150/1.5 reached 100% conversion after 3 h of UV light irradiation.

关键词： TiO2 Coating Polypropylene Propane Photodegradation Photocatalysis

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Virtual ballistic impact testing of Kevlar soft armor:Predictive and validated finite element modeling of the V0-V100 probabilistic penetration response

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defence Technology（防务技术） 2018年第3期14卷 213-225页

作者： Gaurav Nilakantan Suzanne Horner virginia Halls James Zheng Teledyne Scientific&Imaging Thousand OaksCA 91360USA Program Executive Office Soldier Fort BelvoirVA 22060USA

This works presents the first fully validated and predictive capability to model the V_0-V_(100) probabilistic penetration response of a woven fabric using a yarn-level fabric finite element model. The V_0-V_(100) curve describes the probability of complete fabric penetration as a function of projectile impact velocity. The exemplar case considered in this paper comprises of a single-layer, fully-clamped, plain-weave Kevlar fabric impacted at the center by a 17-gr, 0.22 cal FSP or fragment-simulating projectile. Each warp and fill yarn in the fabric is individually modeled using 3 d finite elements and the virtual fabric microstructure is validated in detail against the experimental fabric microstructure. Material and testing sources of statistical variability including yarn strength and modulus, inter-yarn friction, precise projectile impact location, and projectile rotation are mapped into the finite element model. A series of impact simulations at varying projectile impact velocities is executed using LS-dYNA on the fabric models, with each model comprising unique mappings. The impact velocities together with the outcomes(penetration, nonpenetration) are used to generate the numerical V_0-V_(100) curve which is then validated against the experimental V_0-V_(100) curve. The numerical Vi-Vrdata(impact, residual velocities) is also validated against the experimental Vi-Vrdata. For completeness, this paper also reports the experimental characterization data and its statistical analysis used for model input, viz. the Kevlar yarn tensile strengths, moduli, and inter-yarn friction, and the experimental ballistic test data used for model validation.

关键词： Kevlar 有限元素测试数据验证概率预兆弹道虚拟

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Marsh persistence under sea-level rise is controlled by multiple,geologically variable stressors

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Ecosystem Health and Sustainability 2017年第10期3卷 22-38页

作者： M.Mitchell J.Herman d.M.Bilkovic C.Hershner virginia Institute of Marine Science College of William&MaryGloucester PointVAUSA

Introduction:Marshes contribute to habitat and water quality in estuaries and coastal *** importance to continued ecosystem functioning has led to concerns about their ***:Concurrent with sea-level rise,marshes are eroding and appear to be disappearing through ponding in their interior;in addition,in many places,they are being replaced with shoreline stabilization *** examined the changes in marsh extent over the past 40 years within a subestuary of Chesapeake Bay,the largest estuary in the United States,to better understand the effects of sea-level rise and human pressure on marsh ***:Approximately 30 years ago,an inventory of York River estuary marshes documented the historic extent of *** were resurveyed in 2010 to examine shifts in tidal marsh extent and *** change varied spatially along the estuary,with watershed changes between a 32%loss and an 11%gain in marsh *** of marsh was apparent in high energy sections of the estuary while there was marsh gain in the upper/riverine section of the estuary and where forested hummocks on marsh islands have become *** showed little change in the small tributary creeks,except in the creeks dominated by fringing marshes and high shoreline ***:differential resilience to sea-level rise and spatial variations in erosion,sediment supply,and human development have resulted in spatially variable changes in specific marsh extents and are predicted to lead to a redistribution of marshes along the estuarine gradient,with consequences for their unique communities.

关键词： Chesapeake Bay climate change coastal resilience marsh change salt marsh sea-level rise tidal wetlands

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State-of-the-art review on multi-criteria decision-making in the transport sector

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第4期7卷 413-431页

作者： George Yannis Angeliki Kopsacheili Anastasios dragomanovits virginia Petraki department of Transportation Planning and Engineering National Technical University of AthensZografou 15773Greece Attiko Metro S.A. Athens 11525Greece

Consistent decision-making requires a structured and systematic evaluation of advantages and disadvantages of different choice *** transport projects,policies or policy measures,and transport options evaluation,various multi-criteria methods have been developed and effectively applied to complement conventional cost effectiveness and cost benefit *** present paper aims to present a state-of-the-art review of pertinent literature regarding multi-criteria decision-making(MCd M)in the transport sector,focusing on the basic concepts and procedure for multi-criteria decision-making in the transport sector,along with its role and evaluation parameters.A large selection of over 50 papers and publications between 1982 and 2019 have been reviewed,in order to provide an insight into the uses of MCdM methods in transport *** commonly used MCdM metho ds techniques are identified and discussed through a wide review of pertinent literature,research and case studies,leading to interesting conclusions that provide a valuable insight into the use of multicriteria analysis techniques in transport sector related *** on the wide range of reviewed literature,it is concluded that MCdM methods are being applied mostly to evaluate transport options rather than transport policies or projects and the most commonly used MCdM method in transport sector problems are analytic hierarchy process(AHP).

关键词： Traffic engineering Multi-criteria analysis Multiple-attribute decision-making Multiple-objective decision-making

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The Role of Public Health Within the United Nations Post-2015 Framework for disaster Risk Reduction

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International Journal of disaster Risk Science 2015年第1期6卷 28-37页

作者： virginia Murray Amina Aitsi-Selmi Kevin Blanchard Public Health Strategy division Public Health England

This article explores the role of public health systems before, during, and after disasters, particularly within the scope of the United Nations Post-2015 Framework for disaster Risk Reduction. It also examines the role of scientific and technological developments in assisting with improving the resilience of public health professionals and the communities they work in. In addition, it explores how the wide-ranging activities in public health have already contributed to the improved management of disasters and a decrease in associated risks. The article identifies areas of synergy in five key areas of recent policy and practice in public health(the health systems approach, risk assessments, the WHO/UNISdR/HPA disaster Risk Management fact sheets, chronic disease and disasters, and mental health impacts following disasters) and makes suggestions based on lessons identified from the previous(2005) global disaster risk reduction framework. In particular, we advocate the use of scientific evidence that addresses health and disaster risk simultaneously to increase the effectiveness of policy and practice in disaster risk reduction, health, and public health.

关键词： disaster risk reduction Health systems Post-2015 framework Public health Risk assessments

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