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对高水平乒乓球运动员腿部爆发力和弹跳力的评价(英文)

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体育科研 2005年第3期26卷 80-85页

作者： Francisco Pradas Carlos de Teresa Maricarmen vargas University of Granada & Spanish Table Tennis Association. Spain Andalusian Center of Sport Medicine. St. John of God Hospital. Granada. Spain.Andalusian Center of Sport Medicine. St. John of God Hospital. Granada. Spain.

乒乓球运动是一项非周期性运动,对抗过程中涉及极其复杂的战术、心理和生理因素,球员面对对手的施压需要做出快速反应,其中速度和爆发力是基本的、必备的素质。研究目的:探讨乒乓球运动员腿部爆发力的重要作用。研究方法:本研究选用29... 详细信息

乒乓球运动是一项非周期性运动,对抗过程中涉及极其复杂的战术、心理和生理因素,球员面对对手的施压需要做出快速反应,其中速度和爆发力是基本的、必备的素质。研究目的:探讨乒乓球运动员腿部爆发力的重要作用。研究方法:本研究选用29名优秀运动员为实验对象,其中包括17名男性(年龄23.5±5.5 岁)和12位女性(年龄20.8±2.9岁),均为西班牙国家乒乓球队成员。采用测力台(Ergotester Globus)、Acer笔记本电脑和一些登记册对运动员进行了全蹲跳(CMJ)和半蹲跳(SJ)测试,并对腿部爆发力和弹跳力进行了评价。实验数据的统计处理由SPSS v12.0 和Excel v10.2软件完成。研究结果: 在腿部爆发力和弹跳力方面,男女组存在显著性差异(p<0.001),男运动员优于女性运动员。同样,不同打法的选手之间也存在差异,防守型打法的选手都低于进攻型选手。讨论和结论:在CMJ和SJ测试中,防守型打法的选手腿部爆发力和弹跳力均低于进攻型选手。在实验中成绩较好的男女选手,排名均在西班牙前十二以内,进一步证实了腿部爆发力在此项运动中的重要性,尤其对进攻型打法的选手。其原因可归结为血液中所含睾丸激素水平的高低,男选手高于女选手,进攻型选手高于防守型。

关键词：乒乓球运动运动员腿部爆发力弹跳力性别打法

Numerical and safety considerations about the Daguangbao landslide induced by the 2008 Wenchuan earthquake

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第5期11卷 1019-1035页

作者： Manchao He L.Ribeiro e Sousa AndréMüller Eurípedes vargas Jr. R.L.Sousa C.Sousa Oliveira Weili Gong State Key Laboratory of Geomechanics and deep Underground Engineering(SKLGDUE) China University of Mining and TechnologyBeijingChina Tongji University ShanghaiChina Pontifical Catholic University of Rio de Janeiro Rio de JaneiroBrazil Khalifa University of Science and Technology Abu DhabiUnited Arab Emirates Technical Institute University of LisbonLisbonPortugal

The 2008 Wenchuan earthquake resulted in a large number of fatalities and caused significant economic *** of landslides,many of which are very large,were triggered by the earthquake.A majority of catastrophic landslides were distributed along the central Longmenshan fault system,at the eastern margin of the Tibetan *** of the landslides resulted in sudden damming of rivers causing flooding,which in turn induced secondary sliding *** the most significant landslides,the Daguangbao landslide was the largest in volume with the maximum *** this,a numerical model of the Daguangbao landslide,using the material point method(MPM),was developed to simulate the interaction of the seismic loads imposed on the *** numerical results then are compared with the post-earthquake *** a consequence of the landslide,a nearly vertical head scarp with a maximum height of about 700 m was *** is considered as a high risk situation that requires constant monitoring and ***,we propose a methodology based on Bayesian networks(BNs)to manage the risk associated with the stability of the rockwall at the Daguangbao landslide site.

关键词： Wenchuan earthquake Longmenshan fault Daguangbao landslide Material point method(MPM) Rockwall

Adsorption Study of Acid Red 114 and Basic Blue 3 on Sunflower Stalk

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Journal of Water Resource and Protection 2019年第1期11卷 68-81页

作者： Erika Janneth Montes-Alba Gabriel de Jesús Camargo-vargas Rafael Nikolay Agudelo-Valencia Germán Eduardo Dévora-Isiordia Environmental Engineering Universidad Libre Bogotá Colombia Universidad Libre (Bogotá Branch) Bogotá Colombia Instituto Tecnológico de Sonora Obregón México

The aim of this work was to evaluate the sunflower stalk (SS) as an adsorbent in the removal of red acid 114 (AR 114) and basic blue 3 (BB 3) in aqueous solutions, without any physicochemical treatment, where temperature and concentration were the studied variables. The research was developed by using the batch processing mode;the contact time was one hour, with constant agitation of 200 rpm and pH of 7000 ± 0.050, using a central composite design. The adsorbent was characterized through BET, SEM, acid sites and basic sites, charging point, and infrared. The results indicated that the sunflower stalk was a viable and economical alternative for the removal of water that had been contaminated by dyes, showing a better performance for the AR 114 dye, reaching a 71.96% of removal with respect to the initial load. In addition, the EPI Web software was used to model the environmental performance of colorants.

关键词： Adsorption Textile Dyes Low Cost Adsorbents SEM BET EPI Web

Near-UV light assisted green reduction of graphene oxide films through l-ascorbic acid

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International Journal of Smart and Nano Materials 2021年第1期12卷 20-35页

作者： Jaime Regis Sebastian vargas Andrea Irigoyen Elsa Bramasco-Rivera Jose L.Bañuelos Luis C.delfin Anabel Renteria Ulises Martinez Tommy RockwardYirong Lin department of Mechanical Engineering The University of Texas at El PasoEl PasoTX USA W.M.Keck Center for 3D Innovation the University of Texas at El PasoEl PasoTX USA department of Physics The University of Texas at El PasoEl PasoTX USA Materials Physics and Applications Los Alamos National LaboratoryLos AlamosNM USA department of Mechanical Engineering The University of Texas At El Paso 500 W.University Ave.El Paso TX 79968United States

Recent studies have highlighted the effects of various stimuli on the chemical reduction of graphene oxide(GO)through green reductant L-ascorbic acid(L-AA);however,the combination of near ultraviolet(NUV)light to increase the reduction rate has yet to be thoroughly *** this study,drop-casted GO films were subjected to chemical reduction through L-AA with various levels of exposure under 405 nm NUV *** structure and uniformity of GO stackings that form the film were characterized through scanning electron microscopy(SEM)and wide-angle x-ray scattering(WAXS).Additionally,WAXS was used to track the removal of oxygen-containing functional groups along with Fourier-transform infrared(FT-IR)spectroscopy and x-ray photoelectron spectroscopy(XPS)as a function of L-AA and NUV light exposure *** results demonstrated that the interaction between L-AA and NUV exposure has a significant effect on the reduction of ***,the results that yielded the highest reduction(C-C bond concentration of 60.7%)were the longest L-AA and NUV light exposure times(48 hours and 3 hours,respectively).This report provides a study on the effects of NUV on the green reduction of GO films through L-AA with potential application in solar energy and chemical sensing applications.

关键词： Graphene Oxide Films Green Reduction Near Ultraviolet Light L-Ascorbic Acid Wide-Angle X-Ray Scattering

Nitric oxide and hydrogen sulfide share regulatory functions in higher plant events

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BIOCELL 2022年第1期46卷 1-5页

作者： FRANCISCO J.CORPAS SALVADOR GONZÁLEZ-GORDO MARTA RODRÍGUEZ-RUIZ MARÍA A.MUÑOZ-vargas JOSÉM.PALMA Group of Antioxidants Free Radicals and Nitric Oxide in BiotechnologyFood and AgricultureDepartment of BiochemistryCell and Molecular Biology of PlantsEstación Experimental del Zaidín(Spanish National Research CouncilCSIC)Granada18008Spain

Nitric oxide(NO)and hydrogen sulfide(HS)are two molecules that share signaling properties in plant and animal cells NO and H2S originate two farmilies of de rived mol ecules designated reactive nitrogen and sulfur species(RNS and RSS,respectively).These molecules are responsible for certain protein regulatory processes through posttranslational modifications(PTMs),being the most remarkable S nitrosation and persufidation,which afect the thiol group of cysteine *** and H2S can also exert regulatory functions due to their interaction through the iron present in proteins that contain heme groups or iron-sulfur dlusters,as reported mainly in animal ***,the available information in plant cells is still very limited thus *** higher plants,NO and H2S are involved in a myriad of physiological events from seed germination to fruit ripening,but also the mec hanism of response to biotic and abiotic stress *** vie wpoint manuscript highlights the functional regulatory parllelism of these two molecules which also interact with the metabolism of reactive oxygen species(ROS)in plant cells.

关键词： Ascorbate peroxidase Hydrogensulfide Nitricoxide Persulfidation S-nitrosation Signaling

Vigorous,but differential mononuclear cell response of cirrhotic patients to bacterial ligands

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World Journal of Gastroenterology 2011年第10期17卷 1317-1325页

作者： Varenka J Barbero-Becerra María Concepción Gutiérrez-Ruiz Carmen Maldonado-Bernal Félix I Téllez-Avila Roberto Alfaro-Lara Florencia vargas-Vorácková department of Gastroenterology Instituto Nacional de Ciencias Médicasy Nutrición Salvador Zubirán Laboratorio de Fisiología Celular División de Ciencias de la Salud Universidad Autónoma Metropolitana-Iztapalapa Unidad de Investigación Médica en Enfermedades Infecciosasy Parasitarias Hospital de Pediatría Unidad de Investigación en Enfermedades Oncológicas Hospital Infantil de México Federico Gómez

AIM： To study the role of gram-positive and gram-negative bacteria in the pathogenesis of liver injury, specifically the activation of inflammatory mediators. METHODS： Peripheral blood mononuclear cells of 20 out-patients were studied, 10 of them with cirrhosis,Peripheral blood mononuclear cells were isolated and exposed to lipopolysaccharide or lipoteichoic acid. CD14, Toll-like receptor 2 and 4 expression was determined by flow cytometry, and tumor necrosis factor （TNF） α, interleukin （1L）-1β, IL-6, IL-12 and IL-10 secretion in su- pernatants was determined by ELISA. RESULTS： Higher CD14, Toll-like receptor 2 and 4 expression was observed in peripheral blood mononudear cells from cirrhotic patients, （P 〈 0.01, P 〈 0.006, P 〈 0.111） respectively. Lipopolysaccharide and lipoteichoic acid induced a further increase in CD14 expression （P 〈 0.111 lipopolysaccharide, P 〈 0.013 lipoteichoic acid）, and a decrease in Toll-like receptor 2 （P 〈 0.008 lipopolysaccharide, P 〈 0.008 lipoteichoic acid） and Toll-like receptor 4 （P 〈 0.008 lipopolysaccharide, P 〈 0.028 li- poteichoic acid） expression. With the exception of TNFα, absolute cytokine secretion of peripheral blood mononuclear cells was lower in cirrhotic patients under nonexposure conditions （P 〈 0.070 IL-6, P 〈 0.009 IL-1]5, P 〈 0.022 IL-12）. Once exposed to lipopolysaccharide or lipoteichoic acid, absolute cytokine secretion of peripheral blood mononuclear cells was similar in cirrhotic and non-cirrhotic patients, determining a more vigorous response in the former （P 〈 0.005 TNFα, IL-1β, IL-6, IL-2 and IL-10 lipopolysaccharide; P 〈 0.037 TNFα; P 〈 0.006 IL-113; P 〈 0.005 IL-6; P 〈 0.007 IL-12; P 〈 0.014 IL-10 lipoteichoic acid）. Response of peripheral blood mononuclear cells was more intense after lipopolysaccharide than after lipoteichoic acid exposure. CONCLUSION： Peripheral blood mononuclear cells of cirrhotic patients are able to respond to a sudden bacterial ligand exposure, particularly lipopolysaccharide, sugg

关键词： Liver cirrhosis Toll-like receptors Cytokines Lipopolysaccharide Lipoteichoic acid

Nucleocytoplasmic Gynodioecy

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Applied Mathematics 2013年第12期4卷 1658-1668页

作者： R. Doroteo J. A. vargas CIIDIR-Oaxaca Instituto Politécnico Nacional Xoxocotlán México departamento de Ciencias Básicas Instituto Tecnológico de Oaxaca Oaxaca México

We study the evolution of a gynodioecious species under mixed-mating through a nucleocytoplasmic male sterility model. We consider two cytoplasmic types and a nuclear locus with two alleles. Here, the interaction between one cytoplasmic type and a recessive nuclear male-sterility factor gives rise to only one female genotype, while the remaining types correspond to hermaphroditic plants. We include two fitness paramaters: the advantageous female fitness t of females relative to that of hermaphrodites;and a silent and dominant cost of restoration, that is, a diminished fitness for plants carrying a dominant restorer gene relative to that of hermaphrodites. The parameter related to the cost of restoration is assumed to be present on outcrossing male fertility only. We find that every population converges to a stable population. We also determine the nature of the attracting stable population, which could be a nucleocytoplasmic polymorphism, a nuclear polymorphism or another population with some genotypes absent. This depends on the position of t with respect to critical values expressed in terms of the other parameters and also on the initial population.

关键词： Population Genetics Gynodioecy Dynamical System Nucleocytoplasmic Interaction Matrix of Linear Forms

Air Pollution in the Brazilian Road Transport and Its Environmental and Social Consequences

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Journal of Environmental Protection 2014年第15期5卷 1466-1476页

作者： Geórgia Amaral Mothé Marcelo Silva Sthel Maria Priscila Pessanha de Castro Rosane Toledo Alexandre Stumbo Marcelo Gomes Israel Esquef Helion vargas Laboratory of Physical Sciences North Fluminense State University Center for Science and Technology Campos dos Goytacazes Brazil Laboratory of Chemical Sciences North Fluminense State University Center for Science and Technology Campos dos Goytacazes Brazil

The use of fossil fuels has been greatly increased since the eighteenth century with advent of the industrial revolution. Currently, the use of these fuels is responsible for, on average, 80% of energy generation in human society, producing large emission of pollutant gases and particulate material. Thus the transport sector is a major source of air pollution worldwide. This issue causes serious damages to the environment through phenomena such as acid rain, global warming and photochemical smog. Moreover, the emission of pollutants is also related to damages in human health. Brazil is a country with great territorial dimensions and its transport array is eminently by road, so it is a major consumer of fossil fuels, such as diesel, which has been producing serious environmental and social problems. Thus, this paper presents an analysis of the emission of gaseous pollutants and particulate matter from the transport sector (buses and trucks), gaseous pollutants such as NO2 and SO2 were detected in ppmv concentrations using electrochemical sensors. The composition constituents of the particulate materials emitted in diesel combustion and their respective concentrations were determined by X rays fluorescence spectrometry (XRF). The identified elements were: S, Fe, Si, Ca, Zn, P, Ni, Cr, Ti, Mn and Cu.

关键词： Pollutant Gases Particulate Materials Electrochemical Sensors X-Ray Fluorescence

Polyphenols as potential enhancers of stem cell therapy against neurodegeneration

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Neural Regeneration Research 2022年第10期17卷 2093-2101页

作者： Diana Rodríguez-Vera Antonio Abad-García Nancy vargas-Mendoza Rodolfo Pinto-Almazán Eunice D.Farfán-García José A.Morales-González Marvin A.Soriano-Ursúa Sección de Estudios de Posgrado e Investigación.Escuela Superior de Medicina Instituto Politécnico NacionalMéxico CityMéxico Unidad de Investigación Hospital Regional de Alta Especialidad IxtapalucaCarretera Federal México-Puebla km 34.5State of MéxicoMéxico

The potential of polyphenols for treating chronic-degenerative diseases(particularly neurodegenerative diseases)is ***,the selection of the best polyphenol for each treatment,the mechanisms by which they act,and their efficacy are frequently *** this review,the basics and the advances in the field,as well as suggestions for using natural and synthetic polyphenols alone or in a combinatorial strategy with stem cell assays,are compiled and ***,stem cells exhibit several responses when polyphenols are added to their environment,which could provide us with knowledge for advancing the elucidation of the origin of *** also,polyphenols are being included in the innovative strategies of novel therapies for treating neurodegenerative diseases as well as metabolic diseases related to *** this regard,flavonoid compounds are suggested as the best natural polyphenols due to their several mechanisms for acting in ameliorative effects;but increasing reports are involving other *** if some facts limiting bioactivity prevent them from conventional use,some natural polyphenols and derivatives hold the promise for being improved compounds,judged by their induced *** current results suggest polyphenols as enhancers of stem cell therapy against the targeted diseases.

关键词： Alzheimer’s disease chronic degenerative diseases combinatorial therapy metabolism neurodegenerative diseases neuronal damage neuroprotection Parkinson’s disease polyphenols stem cell assays