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Feasibility of the 2-poi.t method to determine the load-velocity relationship variables during the countermovement jump exercise

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Journal of Sport and Health Science 2023年第4期12卷 544-552,F0003页

作者： Alejandro Pérez-Castilla Rodrigo Ramirez-Campillo John F.t.Fernandes Amador García-Ramos Department of Physical Education and Sport Faculty of Sport SciencesUniversity of GranadaGranada 18011Spain Human Performance Laboratory Department of Physical Activity SciencesUniversidad de Los LagosSantiago 5170000Chile Centro de investigacion en Fisiologıa del Ejercicio Facultad de CienciasUniversidad MayorSantiago 8580745Chile Higher Education Sport Hartpury UniversityHartpury GL193BEUK Department of Sports Sciences and Physical Conditioning Faculty of EducationUniversidad Catolica de la Santısima ConcepcionConcepcion 4090541Chile

Purpose:this study aimed to examine the reliability and validity of load-velocity(L-V)relationship variables obtained through the 2-poi.t method using different load combinations and velocity ***:twenty men performed 2 identical sessions consi.ting of 2 countermovement jumps against 4 external loads(20 kg,40 kg,60 kg,and80 kg)and a heavy squat against a load linked to a mean velocity(MV)of 0.55 m/s(load_(0.55)).the L-V relationship variables(load-axis i.tercept(L_(0)),velocity-axis i.tercept(v_(0)),and area under the L-V relationship line(A_(line)))were obtained using 3 velocity variables(MV,mean propulsive velocity(MPV),and peak velocity)by the multiple-poi.t method including(20-40-60-80-load_(0.55))and excluding(20-40-60-80)the heavy squat,as well as from their respective 2-poi.t methods(20-load_(0.55)and 20-80).Results:the L-V relationship variables were obtained with an acceptable reliability(coefncient of vari.tion(CV)≤7.30%;i.tra-class correlation coefficient>0.63).the reliability of L_(0)and v_(0)was comparable for both methods(CV_(ratio)(calculated as higher value/lower value):1.11-1.12),but the multiple-poi.t method provided Al_(ine)with a greater reliability(CV_(ratio)=1.26).the use of a heavy squat provided the L-V relationship variables with a comparable or higher reliability than the use of a heavy countermovement jump load(CV_(ratio):1.06-1.19).the peak velocity provided the load-velocity relationship variables with the greatest reliability(CV_(ratio):1.15-1.86)followed by the MV(CV_(ratio):1.07-1.18),and finally the *** 2-poi.t methods only revealed an acceptable validity for the MV and MPV(effect size≤0.19;Pearson s product-moment correlation coefficient≥0.96;Lin's concordance correlation coefficient≥0.94).Conclusion:the 2-poi.t method obtained from a heavy squat load and MV or MPV is a quick,safe,and reliable procedure to evaluate the lower-body maximal neuromuscular capacities through the L-V relationship.

关键词： Force-velocity relationship Mean velocity Multiple-poi.t method Peak velocity Velocity-based training

Synthesis of tiN/a-Si_3N_4 thin film by using a Mather type dense plasma focus system

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Chinese Physics B 2013年第5期22卷 381-385页

作者： t. Hussain R. Ahmad N. Khalid Z. A. Umar A. Hussnain Center For Advanced Studies in Physics (CASP) 1-Church RoadGC University Department of Physics Government College University

A 2.3 kJ Mather type pulsed plasma focus device was used for the synthesis of a tiN/a-Si3N4 thin film at room temperature. the film was characterized using X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, scanning electron microscopy （SEM）, and atomic force microscopy （AFM）. the XRD pattern confirms the growth of polycrystalline tiN thin film. the XPS results indicate that the synthesized film is non-stoichiometric and contains titanium nitride, silicon nitride, and a phase of silicon oxy-nitride. the SEM and AFM results reveal that the surface of the synthesized film is quite smooth with 0.59 nm roughness （root-mean-square）.

关键词： plasma focus tiN/a-Si3N4 films X-ray diffraction

Viral vector platforms within the gene therapy landscape

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Signal transduction and targeted therapy 2021年第3期6卷 664-687页

作者： Jote t.Bulcha Yi Wang Hong Ma Phillip W.L.tai Guangping Gao Horae Gene therapy Center University of Massachusetts Medical SchoolWorcesterMAUSA Department of Microbiology and Physiological Systems University of Massachusetts Medical SchoolWorcesterMAUSA Department of Pathophysiology West China College of Basic medical sciences&Forensic MedicineSichuan UniversityChengduChina ViDE Program University of Massachusetts Medical SchoolWorcesterMAUSA Li Weibo institute for Rare Diseases Research University of Massachusetts Medical SchoolWorcesterMAUSA

throughout its 40-year hi.tory,the field of gene therapy has been marked by many *** has seen great strides in combating human disease,has given hope to patients and families with limited treatment options,but has also been subject to many *** of patients with this class of investigational drugs has resulted in severe adverse effects and,even in rare cases,*** the heart of this dichotomous field are the viral-based vectors,the delivery vehicles that have allowed researchers and clinicians to develop powerful drug platforms,and have radically changed the face of *** the past 5 years,the gene therapy field has seen a wave of drugs based on viral vectors that have gained regulatory approval that come in a vari.ty of designs and purposes,these modalities range from vector-based cancer therapies,to treating monogenic diseases with life-altering *** present,the three key vector strategies are based on adenoviruses,adeno-associ.ted viruses,and *** have led the way in preclinical and clinical successes in the past two ***,despite these successes,many challenges still limit these approaches from attaining their full *** review the viral vector-based gene therapy landscape,we focus on these three highly regarded vector platforms and describe mechanisms of action and their roles in treating human disease.

关键词： drugs landscape approval

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绝缘物上硅晶体管的栅氧化物质量

微电子学 1988年第4期 64-65页

作者： t.i.Kamins 江碧蓉

本文通过测量氧化物的初始击穿强度和与时间相关的介质击穿,估计了在硅片表面下注入氧化层后,在硅薄膜上生长的栅氧化物的质量。初始介质强度和击穿电荷与体硅片上生长的氧化物是相同的,因而作者认为硅膜里的高位错密度,不会使氧化物的... 详细信息

本文通过测量氧化物的初始击穿强度和与时间相关的介质击穿,估计了在硅片表面下注入氧化层后,在硅薄膜上生长的栅氧化物的质量。初始介质强度和击穿电荷与体硅片上生长的氧化物是相同的,因而作者认为硅膜里的高位错密度,不会使氧化物的质量严重下降。

关键词：击穿强度绝缘物硅膜电流电气强度玻璃膜半导体膜硅片 SiMOX 质量

Anticancer activity test of ethyl acetate extract of endophytic fungi isolated from soursop leaf(Annona muricata L.)

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Asian Pacific Journal of tropical Medicine 2017年第6期10卷 635-640页

作者： Minarni i Made Artika Heddy Juli.tiono Nurliani Bermawie Eny ida Riyanti Hasim Akhmad Endang Zainal Hasan Department of Biochemi.try Faculty of Mathematics and SciencesBogor Agricultural UniversityDarmaga CampusBogor 16680Indonesia Research Center for Biology The Indonesian Institute of Sciences(LIPI)Cibinong-Bogor Indonesia Research institute of Medicinal and Aromatic Plants Agricultural Research AgencyBogor-Indonesia Center for Bi.technology and Genetic Resources of Agriculture Agricultural Research AgencyBogor-Indonesia

Objective: to analyze anticancer activity of an ethyl acetate extract of endophytic fungi isolated from soursop leaf(Annona muricata L.). Methods: Anticancer activity of fungal extracts was determined by observing its toxicity against MCF-7(Michigan Cancer Foundation-7) cells in vitro by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(Mtt) assay method. At an extract concentration of 100 μg/m L, 4 isolates out of 12 showed high activity against the cancer cell growth. the four isolates were then selected for further iC50 determination, by measuring the inhibition of cancer cell proliferation at extract concentration of 25 μg/m L, 50 μg/m L, 100 μg/m L, 200 μg/m L and 400 μg/m L. Results: Results showed that isolate Sir-G5 had the highest anticancer activity with an iC50 of 19.20 μg/m L. the best isolates were screened again using a normal cell(Chang cells) to determine its toxicity against normal cells. Results indicated that the extracts do not affect the proliferation of normal cells. Molecular identification showed that the fungal isolate Sir-G5 has a close relationship with Phomopsis sp. Conclusions: the endophytic fungi isolated from soursop leaf has the potential to be used as a source of anticancer agents.

关键词： Annona muricata L Anticancer MCF-7 Endophytic fungi Soursop leaf

impact of tillage and Fertilizer Application Method on Gas Emissions in a Corn Cropping System

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Pedosphere 2012年第5期22卷 604-615页

作者： K. SMitH D. WAttS t. WAY H. tORBERt S. PRiOR Department of Math Science and Technology University of Minnesota Crookston Crookston MN 56716 (USA) USDA-ARS National Soil Dynamics Laboratory 411 S. Donahue Dr. Auburn AL 36832 (USA)

tillage and fertilization practices used in row crop production are thought to alter greenhouse gas emissions from soil. this study was conducted to determine the impact of fertilizer sources, land management practices, and fertilizer placement methods on greenhouse gas （CO2, CH4, and N2O） emissions. A new prototype implement developed for applying poultry li.ter in subsurface bands in the soil was used in this study. the field site was located at the Sand Mountain Research and Extension Center in the Appalachian Plateau region of northeast Alabama, USA, on a Hartsells fine sandy loam （fine-loamy, siliceous, subactive, thermic typic Hapludults）. Measurements of carbon dioxide （CO2）, methane （CH4）, and nitrous oxide （N20） emissions followed GRACEnet （greenhouse gas reduction through agricultural carbon enhancement network） protocols to assess the effects of different tillage （conventional vs. no-tillage） and fertilizer placement （subsurface banding vs. surface application） practices in a corn （Zea mays L.） cropping system. Fertilizer sources were urea-ammonium nitrate （UAN）, ammonium nitrate （AN） and poultry li.ter （M） applied at a rate of 170 kg ha^（-1） of available N. Banding of fertilizer resulted in the greatest concentration of gaseous loss （CO2 and N2O） compared to surface applications of fertilizer. Fertilizer banding increased CO2 and N2O loss on various sampling days throughout the season with poultry li.ter banding emi.ting more gas than UAN banding. Conventional tillage practices also resulted in a higher concentration of CO2 and N2O loss when evaluating tillage by sampling day. throughout the course of this study, CH4 flux was not affected by tillage, fertilizer source, or fertilizer placement method. these results suggest that poultry li.ter use and banding practices have the potential to increase greenhouse gas emissions.

关键词： conventional tillage global warming potential greenhouse gases no-tillage poultry li.ter

Platinum-group Mineral(PGM) and Base-metal Sulphide(BMS) inclusions in Chromitites of the Zedang Ophiolite, Southern tibet, China and their Petrogenetic Significance

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Acta Geologica Sinica(English Edition) 2016年第3期90卷 900-912页

作者： GUO Guolin YANG Jingsui Paul t.ROBiNSON LiU Xiaodong XU Xiangzhen XiONG Fahui State Key Laboratory Breeding Base of Nuclear Resources and Environment East China University of Technology CARMA State Key Laboratory of Continental Tectonics and Dynamics Institute of Geology Chinese Academy of Geological Sciences School of earth sciences East China University of Technology

Voluminous platinum-group mineral （PGM） inclusions including erlichmanite （Os,Ru）S2, laurite （Ru,Os）S2, and irarsite （ir, Os,Ru,Rh）AsS, as well as native osmium Os（ir） and inclusions of base metal sulphides （BMS）, including millerite （NiS）, heazlewoodite （NiaS2）, covellite （CuS） and digenite （Cu3S2）, accompanied by native iron, have been identified in chromitites of the Zedang ophiolite, tibet. the PGMs occur as both inclusions in magnesiochromite grains and as small i.terstitial granules between them; most are less than 10 ~m in size and vary in shape from euhedral to anhedral. they occur either as single or composite （biphase or polyphase） grains composed solely of PGM, or PGM associ.ted with silicate grains. Os-, ir-, and Ru-rich PGMs are the common species and Pt-, Pd-, and Rh-rich vari.ties have not been identified. Sulfur fugacity and temperature appear to be the main factors that controlled the PGE mineralogy during crystallization of the host chromitite in the upper mantle. if the activity of chalcogenides （such as S, and As） is low, PGE clusters will remain suspended in the silicate melt until they can coalesce to form alloys. Under appropri.te conditions of fS2 and fO2, PGE alloys might react with the melt to form sulfides-sulfarsenides. thus, we suggest that the Os, ir and Ru metallic clusters and alloys in the Zedang chromitites crystallized first under high temperature and low fS2, followed by crystallization of sulphides of the laurite-erlichmanite, solid-solution series as the magma cooled and fS2 increased. the abundance of primary BMS in the chromitites suggests that fS2 reached relatively high values during the final stages of magnesiochromite crystallization. the diversity of the PGE minerals, in combination with differences in the petrological characteri.tics of the magnesiochromites, suggest different degrees of partial melting, perhaps at different depths in the mantle. the estimated parental magma composition suggests formation in a suprasubdu

关键词： chromite ophiolite petrogenetic PGM Zedang

大石围天坑群地下河沉积物中PAHs的污染特征

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环境科学与技术 2011年第8期34卷 42-48,159页

作者：孔祥胜祁士华 Oramah i.t 黄保健张原中国地质大学(武汉)教育部生物地质和环境地质重点实验室湖北武汉430074 中国地质科学院岩溶地质研究所广西桂林541004 中国地质科学院岩溶生态系统与石漠化治理重点开放实验室广西桂林541004

为探索喀斯特地下河沉积物中多环芳烃(PAHs)的污染特征、来源,研究选择典型的广西乐业大石围天坑群地下河进行,沿途采集7个断面的沉积物样品,利用气相色谱-质谱(GC-MS)对16种优控PAHs进行定量分析.结果表明,大石围天坑群地下河上层沉积... 详细信息

为探索喀斯特地下河沉积物中多环芳烃(PAHs)的污染特征、来源,研究选择典型的广西乐业大石围天坑群地下河进行,沿途采集7个断面的沉积物样品,利用气相色谱-质谱(GC-MS)对16种优控PAHs进行定量分析.结果表明,大石围天坑群地下河上层沉积物中总PAHs浓度为37.75～1 662.72 ng/g,下层沉积物为43.46～1 220.79 ng/g,大部分采样点上、下层浓度没有明显的变化.研究显示,沉积物中PAHs浓度进口高于出口,进口以4～6环的为主,出口以2～3环的为主;由于正辛醇-水分配系数(lgKOW)的差异,在地下河中4～6环PAHs显示近距离迁移,而2～3环PAHs显示远距离迁移;由于沉降和吸附作用,地下河环境对污水中的PAHs具有较强的净化作用;通过PAHs成份谱比较,发现沿途大石围天坑群的"冷陷阱效应"富集作用及土壤侵蚀作用使大石围河段沉积物中的PAHs增加了106%;比值法来源分析,表征县城区域沉积物中PAHs的来源为石油类和燃烧源的混合源,乡村区域以草、木燃和煤燃烧源为主;生态风险评价显示地下河沉积物中PAHs的污染处于较低的生态风险水平。

关键词：多环芳烃大石围天坑群地下河沉积物喀斯特污染特征

Mobile Devices i.terface Adaptivity Using Ontologies

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Computers, Materials & Continua 2022年第6期71卷 4767-4784页

作者： Muhammad Waseem iqbal Muhammad Raza Naqvi Muhammad Adnan Khan Faheem Khan t.Whangbo Department of Software Engineering The Superior UniversityLahore53700Pakistan iNP-ENit University of ToulouseTarbes65000France Riphah School of Computing&innovation Faculty of ComputingRiphah International University Lahore CampusLahore54000Pakistan Pattern Recognition and Machine Learning Lab Department of SoftwareGachon UniversitySeongnam13557Korea Department of Computer Engineering Gachon UniversitySeongnam13557Korea

Currently,many mobile devices provide various i.teraction styles and modes which create complexity in the usage of *** context offers the information base for the development of Adaptive user i.terface(AUi)frameworks to overcome the *** this purpose,the ontological modeling has been made for specific context and *** type of philosophy states to the relationship among elements(e.g.,classes,relations,or capacities etc.)with understandable satisfied *** contextmechanisms can be examined and understood by anymachine or computational framework with these formal definitions expressed in Web ontology language(WOL)/Resource descri.tion frame work(RDF).the Protégéis used to create taxonomy in which system is framed based on four contexts such as user,device,task and *** competency questions and use-cases are utilized for knowledge obtaining while the information is refined through the instances of concerned parts of context *** consi.tency of the model has been verified through the reasoning software while SPARQL querying ensured the data availability in the models for defined *** semantic context model is focused to bring in the usage of adaptive *** exploration has finished up with a versatile,scalable and semantically verified context learning *** model can be mapped to individual User i.terface(Ui)display through smart calculations for versatile Uis.

关键词： User context adaptive i.terfaces human computer i.teraction