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Effects of Eccentric Pre-loading on Concentric Vertical Jump Performance in Young Female Athletes

Journal of Science in Sport and Exercise 2021年第1期3卷 98-106页

作者： Zachary M.Gillen Marni E.Shoemaker Nicholas A.Bohannon Sydney M.Gibson joel t.Cramer Department of Kinesiology Mississippi State University236 McCarthy GymnasiumStarkvilleMS 39762USA College of Health Sciences The University of Texas at El PasoEl PasoTX 79968USA College of Medicine University of Nebraska Medical CenterOmahaNE 68198USA Department of Nutrition&Health Sciences University of Nebraska-LincolnLincolnNE 68583USA

Purpose this study examined changes in vertical jump performance with progressively greater eccentric pre-loading in relation to growth and development in young female *** twenty young female athletes ranging from 9 to 17 years old performed the following vertical jumps in random order:static jumps(SJs),counter-movement jumps(CMJs),and drop jumps(DJs)from drop heights of 20,30,and 40 cm(DJ20,DJ30,and DJ40,respectively).Measurements included peak force(PF),peak rate of force development(RFD),peak power(PP),eccentric impulse(ECC),and concentric impulse(CON).Measurements of growth included age,maturity offset,height,body mass,fat-free mass,and thigh muscle cross-sectional area(CSA).Results PF increased from the SJ-DJ20(Pthen plateaued from DJ20-DJ40(P=1.000).RFD remained the same from SJ-CMJ(P=1.000),increased from CMJ-DJ20(Pteaued from DJ20-DJ40(P=0.874).PP increased from the SJ-CMJ(Pthen plateaued from the CMJ-DJ40(P≥0.486).CON remained the same across all verti-cal jumps(P=1.000),while ECC increased from the SJ-DJ40(P≤0.038).Jump height(JH)increased from the SJ-CMJ(Pteaued from DJ20-DJ40(P=1.000).the change in PP from the SJ-CMJ(ΔCMJ-SJ)was related to all measurements of growth except CSA(r=0.558-0.815).Conclusion Young females produced greater power during the CMJ than SJ,but equivalent power from the CMJ-DJ40,despite increases in ***,ΔCMJ-SJ was not related to CSA,which suggests other underlying mechanisms affect stretch-shortening cycle utilization in young female athletes.

关键词： Stretch-shortening cycle Youth Ground reaction force Kinetics

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Computational discovery of ultra-strong, stable, and lightweight refractory multi-principal element alloys. Part II: comprehensive ternary design and validation

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npj Computational Materials 2023年第1期9卷 1469-1481页

作者： Kate L.M.Elder joel Berry Aurélien Perron Brandon Bocklund Jibril Shittu Connor J.Rietema Hunter B.Henderson Scott K.McCall Joseph t.McKeown Materials Science Division Lawrence Livermore National LaboratoryLivermoreCA 94550USA.✉

Here the discovery of refractory multi-principal element alloys(MPEAs)with high-temperature strength and stability is pursued within a constrained and application-relevant design space.A comprehensive approach is developed and applied to explore all 165 ternary systems in the Al-Ce-Fe-Hf-Mo-Nb-ta-ti-V-W-Zr family.A subset of ternary systems that contain large areas in composition–temperature space with high strength and robust BCC phase stability is *** sets of high-performing alloys are identified,each set optimized for one combination of phase constraint,optimization target,and temperature *** mechanical tests support the viability of the *** work highlights the importance of considering phase stability,exploring non-equiatomic regions of composition space,and applying application-relevant *** I and II provide three down-selection techniques for identifying high-performing BCC refractory MPEAs,design guidelines,and many candidates predicted to have BCC phase stability and strengths 2–3 times higher than any reported to date.

关键词： alloys element ternary

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Reconstructing f(t) modified gravity from ECHDE and ECNADE models

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Communications in theoretical Physics 2020年第9期72卷 75-88页

作者： A E Godonou Ines G Salako M J S Houndjo Etienne Baffou joel tossa Institut de Mathematiques et de Sciences Physiques(IMSP) 01 BP 613 Porto-NovoBenin Ecole de Genie Rural(EGR) 01 BP 55 KetouBenin Faculte des Sciences et techniques de Natitingou(FASt) BP 72NatitingouBenin

We investigate alternative candidates to dark energy(DE) that can explain the current state of the Universe in the framework of the generalized teleparallel theory of gravity f(t), where t denotes the torsion scalar. to achieve this, we carry out a series of reconstructions taking into account the ordinary and entropy-corrected versions of the holographic and new agegraphic DE *** models are used as alternatives to DE in the literature in order to describe the current state of our Universe. It is remarked that the proposed models indicate behavior akin to phantom or quintessence models. Furthermore, we also generate the parameters of the equation of state associated with entropy-corrected models and we observe a phase transition between the quintessence state and phantom state as it is shown by the recent observational data. We also investigate the stability of these models and we create the {r-s} trajectories and compare with the ΛCDM limit. the behavior of certain physical parameters such as the speed of sound and the Statefinder diagnostic pair {r-s} is compatible with the current observational data.

关键词： teleparallel gravity ECHDE ECNADE

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Implementation of Network Intrusion Detection System Using Soft Computing Algorithms (Self Organizing Feature Map and Genetic Algorithm)

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Journal of Information Security 2019年第1期10卷 1-24页

作者： joel t.Hounsou thierry Nsabimana Jules Degila Institut de Mathématiques et de Sciences Physiques Porto-NovoBeninUniversitéd’Abomey Calavi

In today’s world, computer network is evolving very rapidly. Most public or/and private companies set up their own local networks system for the purpose of promoting communication and data sharing within the companies. Unfortunately, their data and local networks system are under risks. With the advanced computer networks, the unauthorized users attempt to access their local networks system so as to compromise the integrity, confidentiality and availability of resources. Multiple methods and approaches have to be applied to protect their data and local networks system against malicious attacks. the main aim of our paper is to provide an intrusion detection system based on soft computing algorithms such as Self Organizing Feature Map Artificial Neural Network and Genetic Algorithm to network intrusion detection system. KDD Cup 99 and 1998 DARPA dataset were employed for training and testing the intrusion detection rules. However, GA’s traditional Fitness Function was improved in order to evaluate the efficiency and effectiveness of the algorithm in classifying network attacks from KDD Cup 99 and 1998 DARPA dataset. SOFM ANN and GA training parameters were discussed and implemented for performance evaluation. the experimental results demonstrated that SOFM ANN achieved better performance than GA, where in SOFM ANN high attack detection rate is 99.98%, 99.89%, 100%, 100%, 100% and low false positive rate is 0.01%, 0.1%, 0%, 0%, 0% for DoS, R2L, Probe, U2R attacks, and Normal traffic respectively.

关键词： SOFM Intrusion Detection Systems False Positive Rate Detection Rate KDD Cup 99 GA

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High-throughput computational discovery of In_(2)Mn_(2)O_(7) as a high Curie temperature ferromagnetic semiconductor for spintronics

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npj Computational Materials 2019年第1期5卷 529-535页

作者： Wei Chen Janine George joel B.Varley Gian-Marco Rignanese Geoffroy Hautier Institute of Condensed Matter and Nanoscicence(IMCN) Universitécatholique de Louvain1348 Louvain-la-NeuveBelgium Lawrence Livermore National Laboratory LivermoreCA 94550USA

Materials combining strong ferromagnetism and good semiconducting properties are highly desirable for spintronic applications(e.g.,in spin-filtering devices).In this work,we conduct a search for concentrated ferromagnetic semiconductors through highthroughput computational *** screening reveals the limited availability of semiconductors combining ferromagnetism and a low effective *** identify the manganese pyrochlore oxide In_(2)Mn_(2)O_(7) as especially promising for spin transport as it combines low electron effective mass(0.29m0),a large exchange splitting of the conduction band(1.1 eV),stability in air,and a Curie temperature(about 130 K)among the highest of concentrated ferromagnetic *** rationalise the high performance of In_(2)Mn_(2)O_(7) by the unique combination of a pyrochlore lattice favouring ferromagnetism with an adequate alignment of O–2p,Mn–3d,and In–5s forming a dispersive conduction band while enhancing the Curie temperature.

关键词： temperature ferromagnetic semiconductors

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2-吡嗪羧酸Ni(II),Co(II)和Cu(II)配合物的合成、表征、电化学测试及其催化合成2H-吲哚[2,1-b]酞嗪三酮（英文）

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催化学报 2015年第7期36卷 1101-1108页

作者： Behnaz Afzalian joel t.Mague Maryam Mohamadi S.Yousef Ebrahimipour Behjat Pour amiri Esmat tavakolinejad Kermani DepartmentofChemistry PayamNoorUniversity(PNU)19395-4697Tehranlran DepartmentofChemistry TulaneUniversityNewOrleansLA701/8USA DepartmentofChemistry FacultyofScienceShahidBahonarUniversityofKermanKermanlran

three complexes containing 2-pyrazinecarboxylate(pzca–), including [Ni(pzca)2(H2O)2], [Co(pzca)2(H2O)2], and [Cu(pzca)2(H2O)2], have been synthesized and characterized using physicochemical and spectroscopic methods. Furthermore, the structure of each complex was determined by single-crystal X-ray diffraction. All three complexes have an octahedral geometry, where the metal ion chelated by two carboxylate oxygens, two nitrogen atoms belonging to pyrazinic acid molecules, and two oxygen atoms of two water molecules. the catalytic activities of these complexes were also investigated in the green synthesis of 2H-indazolo[2,1-b]phthalazine-triones by the reaction of hydrazine hydrate with an arylaldehyde, phthalic anhydride, and dimedone in acetic acid.

关键词：绿色合成催化活性配合物吡嗪表征吲唑电化学单晶X-射线衍射

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Reduced Annealing time and Enhanced Magnetocaloric Effect of La(Fe,Al)13 Alloy by La-nonstoichiometry and Si-doping

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Acta Metallurgica Sinica(English Letters) 2020年第11期33卷 1535-1542页

作者： Liang Yang Jun Li Defang tu joel C.J.Strickland Qiaodan Hu Hongbiao Dong Jianguo Li School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Engineering University of LeicesterLeicester LE17RHUK Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai Jiao Tong UniversityShanghai 200240China

LaFe13-x Mx(M=Si,Al)alloys are promising for use in magnetic ***,they require long annealing time(30 days)in order to optimize the magnetocaloric *** has shown that the addition of extra La in off-stoichiometric alloys can greatly shorten the annealing ***,the purpose of this study is to investigate the influence of the extra addition of La on the annealing properties of a new off-stoichiometric La1.7Fe11.6Al1.4-xSix(x=0,0.1,0.4)*** was demonstrated that after a 36 h annealing time,a large volume fraction of 1:13 magnetocaloric phase was obtained for all *** microstructural analysis of the off-stoichiometric La1.7Fe11.6Al1.4-xSix alloys revealed a facet-like grain *** La1.7Fe11.6Al1.4 and La1.7Fe11.6Al1Si0.4 alloys were shown to contain large 1:13 phase precipitates separated in a La-rich matrix,while the La1.7Fe11.6Al1.3Si0.1 alloy had a continuous 1:13 phase matrix with a fine dispersion of La-rich precipitates *** the magnetic field varied between 0 and 2 t,the corresponding magnetic entropy change and relative cooling capacity for the La1.7Fe11.6Al1.3Si0.1 specimen were determined as 4.58 J/kg K and 173.6 J/kg,*** importantly,the La1.7Fe11.6Al1.3Si0.1 alloy displayed only a slight volume change when the meta-magnetic phase transition occurred,which is promising for cyclic use.

关键词： Solidifi cation Magnetic properties Heat treatment Microstructure Functional alloys

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A one-step,tunable method of selective reactive sputter deposition as a wrinkling approach for silver/polydimethylsiloxane for electrically conductive pliable surfaces

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Microsystems & Nanoengineering 2022年第4期8卷 221-231页

作者： joel Y.Y.Loh Ali Zeineddine Moein Shayegannia Robyn McNeil Liam McRae Nazir P.Kherani Department of Electrical and Computing Engineering University of TorontoTorontoON M5S 3G4Canada Department of Material Science and Engineering University of TorontoTorontoON M5S 3E4Canada

the wrinkle period and morphology of a metal thin film on an elastic substrate is typically controlled by modifying the substrate before carrying out additional metal deposition ***,we show that a simultaneously selective and reactive sputtering plasma that modifies the surface of a polydimethylsiloxane(PDMS)substrate while not reacting with the metal during the deposition process decreases the wrinkle wavelength and induces additional wrinkling components and features such as ripples or *** selective reaction of the nitrogen plasma with PDMS functionalizes the siloxane surface into silicon *** hardens the immediate surface of PDMS,with a quadratic increase in the Young’s modulus as a function of the sputtering flow *** increase in the critical strain mismatch and the corresponding presence of folds in the nitrogen-modified wrinkled silver film form a suitable plasmonic platform for surface-enhanced Raman spectroscopy(SERS),yielding an enhancement factor of 4.8×105 for detecting *** enhancement is linked to the emergence of electromagnetic hotspots from surface plasmon polariton coupling between the folds/wrinkles,which in turn enables the detection of low concentrations of organics using ***,when strained,the nitrogen-modified wrinkles enhance electrical conductivity by a factor of 12 compared with unmodified ***,the optical properties of the substrate can be tuned by altering the N2 *** simple addition of nonreactive nitrogen to silver sputtering enables simultaneous PDMS hardening and growth of the silver film and together provide a new avenue for tuning wrinkling parameters and enhancing the electrical conductivity of pliable surfaces.

关键词： silver reactive film

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Urban Air Pollution May Enhance COVID-19 Case-Fatality and Mortality Rates in the United States

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the Innovation 2020年第3期1卷 114-122页

作者： Donghai Liang Liuhua Shi Jingxuan Zhao Pengfei Liu Jeremy A.Sarnat Song Gao joel Schwartz Yang Liu Stefanie t.Ebelt Noah Scovronick Howard H.Chang Gangarosa Department of Environmental Health Rollins School of Public HealthEmory University1518 Clifton Road NEAtlantaGA 30322USA Surveillance and Health Services Research Program American Cancer SocietyAtlantaGAUSA School of Earth and Atmospheric Sciences Georgia Institute of TechnologyAtlantaGAUSA GeoDS Lab Department of GeographyUniversity of Wisconsin-MadisonMadisonWIUSA Department of Environmental Health Harvard T.H.Chan School of Public HealthBostonMAUSA Department of Biostatistics and Bioinformatics Rollins School of Public HealthEmory UniversityAtlantaGAUSA

BACKGROUND the novel human coronavirus disease 2019(COVID-19)pandemic has claimed more than 600,000 lives worldwide,causing tremendous public health,social,and economic *** the risk factors of COVID-19 are still under investigation,environmental factors,such as urban air pollution,may play an important role in increasing population susceptibility to COVID-19 *** We conducted a cross-sectional nationwide study using zero-inflated negative binomial models to estimate the association between longterm(2010–2016)county-level exposures to NO2,PM2.5,and O3 and county-level COVID-19 case-fatality and mortality rates in the United *** used both single-and multi-pollutant models and controlled for spatial trends and a comprehensive set of potential confounders,including state-level test positive rate,county-level health care capacity,phase of epidemic,population mobility,population density,sociodemographics,socioeconomic status,race and ethnicity,behavioral risk factors,and *** From January 22,2020,to July 17,2020,3,659,828 COVID-19 cases and 138,552 deaths were reported in 3,076 US counties,with an overall observed case-fatality rate of 3.8%.County-level average NO2 concentrations were positively associated with both COVID-19 case-fatality rate and mortality rate in single-,bi-,and tri-pollutant *** adjusted for co-pollutants,per interquartile-range(IQR)increase in NO2(4.6 ppb),COVID-19 case-fatality rate and mortality rate were associated with an increase of 11.3%(95%CI 4.9%–18.2%)and 16.2%(95%CI 8.7%–24.0%),*** did not observe significant associations between COVID-19 case-fatality rate and long-term exposure to PM2.5 or O3,although per IQR increase in PM2.5(2.6 mg/m3)was marginally associated,with a 14.9%(95%CI 0.0%–31.9%)increase in COVID-19 mortality rate when adjusted for *** Long-term exposure to NO2,which largely arises from urban combustion sources such as traffic,may enhanc

关键词： AIR POLLUtION NItROGEN DIOXIDE COVID-19 CASEFAtALItY RAtE MORtALItY

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Sex Differences in Delaying Family＂ Effects on Job and Life Satisfaction

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Psychology Research 2011年第6期1卷 444-452页

作者： Joshua Doemer joel t. Nadler Meghan R. Lowery Southern Illinois UniversityCarbondale Carbondale USA Southern Illinois UniversityEdwardsville Edwardsville UAS Psychological Associates St. Louis USA

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