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Commentary on“The deterministic condition for the ground reaction force acting point on the combined knee valgus and tibial internal rotation moments in the early phase of cutting maneuvers in female athletes”

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Journal of Sport and Health Science 2024年第3期13卷 373-375页

作者： Nathan D.Schilaty Nathaniel A.Bates Department of Neurosurgery&Brain Repair University of South FloridaTampaFL 33620USA Department of Medical Engineering University of South FloridaTampaFL 33620USA Center for Neuromusculoskeletal Research University of South FloridaTampaFL 33620USA Department of Orthopaedics The Ohio State University Wexner Medical CenterColumbusOH 43210USA

*** For decades,substantial disagreement has persisted as to whether dynamic knee valgus is the cause of the majority of anterior cruciate ligament(ACL)injuries or rather the result of the ACL rupture.1 Consequently,great effort and expense has gone into capturing 3-dimensional kinetics and kinematics from live athletes to drive in vitro and in silico models of ACL injury in order to elucidate the actual mechanism of injury,as these factors have been demonstrated to be surrogates of intraarticular structural loading on the ACL.2,3 The elucidation of injury mechanisms for non-contact ACL injuries is of great medical value as such knowledge consequently permits quantified examination and validation of interventions and their respective effectiveness in both prevention and rehabilitation of these traumatic knee injuries.

关键词： injuries knee prevention

Evidence on the causes of the rising levels of COD_(Mn) along the middle route of the south-to-North Diversion Project in China:The role of algal dissolved organic matter

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Journal of Environmental Sciences 2022年第3期34卷 281-290页

作者： Chao Wang Hong Zhang Pei Lei Xiaokang Xin Aijing Zhang Wei Yin Changjiang Water Resources Protection Institute Wuhan 430051China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Laboratory of Pollution Control and Resources Reuse School of the EnvironmentNanjing UniversityNanjing 210046China Construction and Administration Bureau of south-to-North Water Diversion Middle Route Project Beijing 100038China Key Laboratory cf Ecological Regulation ofNon-point Source Pollution in Lake and Reservoir Water Sources Wuhan 430051China

As the biggest inter-basin water transfer scheme in the world,the south-to-North Water Diversion Project(SNWD) was designed to alleviate the water crisis in North *** main channel of the middle route of the SNWD is of great concern in terms of the drinking water *** this study,we tested the hypothesis that the dissolved organic matter(DOM) derived from the planktonic algae causes the rising levels of COD_(Mn) along the middle route by monitoring data on water quality(2015-2019,monthly resolution).The results showed that algal density in the main channel increased along the channel and was significantly correlated with COD_(Mn)(p drive the changes in COD_(Mn).Therefore,controlling algal density would be an important measure to prevent further increase in CODMn and for the guarantee of excellent water quality.

关键词： Dissolved organic matter(DOM)Algae COD_(Mn) south-to-North Diversion Project Danjiangkou reservoir Three-dimensional fluorescence excitation emission matrix spectroscopy(3D-EEMs)

Long-term effects of fire frequency and season on herbaceous vegetation in savannas of the Kruger National Park,south Africa

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Journal of Plant Ecology 2013年第1期6卷 71-83页

作者： Melinda D.Smith Brian Wvan Wilgen Catherine E.Burns Navashni Govender Andre L.F.Potgieter Sandy Andelman Harry C.Biggs Judith Botha Winston S.W.Trollope Department of Ecology and Evolutionary Biology Yale UniversityPO Box 208106New HavenCT 06520USA Centre for Invasion Biology Council for Scientific and Industrial Research Natural Resources and the EnvironmentPO Box 320Stellenbosch 7600South Africa North Carolina Chapter Office The Nature Conservancy4705 University DriveSuite 290DurhamNC 27707USA Scientific Services South African National ParksPrivate Bag X402Skukuza 1350South Africa Tropical Ecology Assessment and Monitoring(TEAM)NetworkConservation International2011 Crystal DriveSuite 500ArlingtonVA 22202USA Department of Livestock and Pasture Science University of Fort HarePrivate Bag X1314Alice 5700South Africa

Aims:The long-term effects of changing fire regimes on the herbaceous component of savannas are poorly understood but essential for understanding savanna *** present results from one of the longest running(>44 years)fire experiments in savannas,the experimental burn plots(EBPs),which is located in the Kruger National Park(south Africa)and encompasses four major savanna vegetation types that span broad spatial gradients of rainfall(450–700 mm)and soil ***:Herbaceous vegetation was sampled twice in the EBPs using a modified step-point method,once prior to initiation of the experiment(1954)and again after 44–47 *** combinations of three fire frequency(1-,2-and 3-year return intervals)and five season(before the first spring rains,after the first spring rains,mid-summer,late summer and autumn)treatments,as well as a fire exclusion treatment,were applied at the plot level(;7 ha each),with each treatment(n=12 total)replicated four times at each of the four sites(n=192 plots total).The effects of long-term alterations to the fire regime on grass community structure and composition were analyzed separately for each *** Findings:Over the 44+years duration of the experiment,fires were consistently more intense on sites with higher mean annual rainfall(>570 mm),whereas fires were not as intense or consistent for sites with lower and more variable rainfall(<510 mm)and potentially higher herbivory due to greater soil *** the plots were open to grazing,the impacts of herbivory along with more variable rainfall regimes likely minimized the effects of fire for the more arid *** a consequence,fire effects on grass community structure and composition were most marked for the higher rainfall sites and generally not significant for the more arid *** the high-rainfall sites,frequent dry season fires(1-to 3-year return intervals)resulted in high grass richness,evenness and diversity,whereas fire exclusion and growing se

关键词： climate fire intensity grass herbivory soil fertility

Achieving fish passage outcomes at irrigation infrastructure;a case study from the Lower Mekong Basin

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Aquaculture and Fisheries 2021年第2期6卷 113-124页

作者： Lee J.Baumgartner Chris Barlow Martin Mallen-Cooper Craig Boys Tim Marsden Garry Thorncraft Oudom Phonekhampheng Douangkham Singhanouvong William Rice Michael Roy Lin Crase Bethany Cooper Institute for Land Water and SocietyCharles Sturt UniversityElizabeth Mitchell DriveAlburyNew South WalesAustralia Department of Primary Industries Port Stephens Fisheries CentrePrivate Bag 1Nelson BayNew South Wales2315Australia Australasian Fish Passage Services 27 Beachside PlaceShoal PointQLD4750Australia National University of Laos PO Box 10864Dongdok CampusVientianeLao Democratic People’s Republic Living Aquatic Resources Research Centre Phonsavang VillageSikhotabong DistrictVientianeLao Democratic People’s Republic United States Department of the Interior International Technical Assistance Program1849 C StreetNWWashington DC20240United States University of south Australia School of CommerceCity West CampusAdelaideSouth AustraliaAustralia

Irrigation infrastructure expansion threatens the diversity of freshwater fish *** infrastructure creates migration barriers which can block access to important nursery,feeding and spawning *** PDR is a landlocked country situated within the Lower Mekong River Basin where there is a substantial dependency on rice and fish for food,income and *** country is experiencing an unprecedented boom in irrigation infrastructure investment,with modernisation programs being implemented in every *** significant investment in infrastructure upgrades,and the potential impact on freshwater fish,little consideration has been given to fish passage *** 2008,we commenced a fish passage program in Lao *** intent of this case study is to outline the pivotal elements of the program of knowledge development and transfer,in the context of river connectivity and fisheries management in Lao *** also highlight challenges in international research in development and lessons learned.

关键词： Fish passage Tropical rivers Lower mekong basin Migration Fishway Lao PDR

Quad-channel broadband compact multi-antenna GNSS down-converter for high-reliability navigation

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Transportation Safety and Environment 2023年第4期5卷 100-106页

作者： Riyan Wang Bin Li Hongyin He Kunming Yang Wei Feng Zhijian Chen School of Microelectronics South China University of TechnologyGuangzhou 510640GuangdongChina Guangzhou Runxin Information Technology Co. LtdGuangzhou 510663GuangdongChina

A high-reliability broadband high-linearity down-converter for multi-antenna global navigation satellite system(GNSS)receiver is presented in this *** on direction-of-arrival estimation,the multi-antenna GNSS receiver can separate the GNSS signals from the interfering signals and suppress harmful broadband radio frequency *** drive the off-chip 50Ω2 resistive load and meet the stringent requirements of linearity,a quad-channel down-converter with a broadband common-gate low-noise transcon-ductance amplifier,current-driven passive mixer and novel bridge mode transimpedance driving amplifier have been proposed to contruct the multi-antenna *** operating frequency of this down-converter is from 1.15 to 1.65 GHz,covering all bands for global positioning system(GPS),Beidou navigation satellite system(BDS),global navigation satellite system(GLONASS)and *** measured results show that the proposed quad-channel down-converter achieves+38 dBm output 3rd order intercept point(OIP3)and+17 dBm OP1dB(output-referred 1 dB compression point),9.5 dB to 12.9 dB noise figure(NF)across the variable gain of 10 dB to 27 dB and approximately 47 dB channel isolation.

关键词： down-converter radio frequency(RF)front-end multi-antenna receiver quad-channel global navigation satellite system(GNSS) broadband

Characterizing receiver clock behaviors onboard Low Earth Orbiters:A case study of GRACE satellites

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Geodesy and Geodynamics 2019年第4期10卷 276-281页

作者： Tzu-Pang Tseng C.K.Shum Ting-Yi Yang Geoscience Australia Jerrabomberra Ave&Hindmarsh DriveSymonstonACT2609Australia Division of Geodetic Science School of Earth SciencesThe Ohio State University125 South Oval MallColumbusOH43210USA Institute of Geodesy and Geophysics Chinese Academy of SciencesWuhanHubei430077China

Accurate estimation of clocks, for example for the Gravity Recovery And Climate Experiment(GRACE)twin-satellites, is a critical part of precise orbit determination(POD) that ensures temporal gravity inversion. Characterizing the periodic variations of the receiver clocks is critical for precise clock modeling and prediction. In this study, the receiver clock is estimated using two different POD procedure: kinematic and reduced-dynamic approaches. Choices and the number of orbital parameters estimated in POD process affect the clock estimates, e.g., there are 8895 and 34,560 total parameters in the reduced-dynamic and kinematic approaches, respectively. In the both cases, the periodic variations of GRACE receiver clock are mainly dominated by the GPS orbit period, as well as once-(1-pr) and twiceper-revolution(2-pr) effects. Here the 1-pr effect is coupled with the relativistic effect, resulting in a difficulty to separate both signals. The clock amplitudes caused by the GPS orbit period, 1-pr and 2-pr are about 0.1, 0.03 and 0.01 ns, respectively. The GPS orbit period is almost one order magnitude larger than the 1-and 2-pr effect. The 0.1-ns amplitude of the 12-h periodic variation is equivalent to a 3-cm error in range. Such a systematic error should be considered in the receiver clock modeling for both the improvement of positioning accuracy and the reduction of number of unknown parameters, if the precise point positioning(PPP) technique is used for the orbit determination of the GRACE.

关键词： GPS GRACE Precision orbit determination Clock modeling

Testing point of Care Portable Data Capture in a Hospital HIV Transmission Prevention Programme and Experience from Computerized Patient Management in a Sub-Saharan Clinic Setting

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Computer Technology and Application 2011年第12期2卷 1015-1022页

作者： Michael Kavuma Maurice Mars Management Sciences for Health Plot 15 Princess Anne Drive Bugolobi P.O Box 71419 Kampala Uganda Department of Tele-Health Nelson R Mandela Medical School University of KwaZulu Natal 719 Umbilo Road 4001 DurbanPrivate Bag 7 Congella 4013 South Africa

Clinicians involved in HIV/AIDS (Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome) prevention of mother to child transmission (PMTCT) programme and research activities can benefit from the advantages that computerized systems add to medical practice even in resource constrained sub-Saharan clinic settings. Their continued use of paper based systems presents clinical data management and patient care challenges. A portable point of care data capture electronic system and a computerized clinic patient management system (CCPMS) were implemented to remedy these challenges. PMTCT report compilation was easier with the portable data collection system whose data were found to be more complete and accurate with a 0.83% error rate compared to a 4.1% error rate in the paper registers. A resounding majority of clinicians preferred using the new CCPMS with many of the view that it improved drug inventory and general clinic management with a positive effect on patient care.

关键词：便携式数据采集系统病毒传播数据管理撒哈拉预防计算机化医疗艾滋病毒

A New DC Side Capacitance Voltages Balancing Method for Three-level Inverters Based on Hybrid Space Vector Modulation

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中国电机工程学报 2012年第27期32卷 I0017-I0017页

作者： Fan Bishuang Tan Guanzheng Fan Shaosheng Deng zelin Central south University Changsha University of Science & Technology

针对二极管中点钳位型(neutral point clamped,NPC)三电平逆变器容易造成直流侧电容电压不平衡问题,提出一种新的中点电位平衡控制方法。在该方法中,采用分扇区精细控制,对不同的小矢量设置不同的时间分配因子,以增加相应正或负小矢量... 详细信息

针对二极管中点钳位型(neutral point clamped,NPC)三电平逆变器容易造成直流侧电容电压不平衡问题,提出一种新的中点电位平衡控制方法。在该方法中,采用分扇区精细控制,对不同的小矢量设置不同的时间分配因子,以增加相应正或负小矢量对中点电流的控制能力。对于正负小矢量不能成对出现的扇区,根据相电流的变化情况,使调制在传统算法和基于虚拟矢量的算法之间切换,从而削弱中矢量对中点电流不可控的影响。仿真和实验证实了该方法的正确性和有效性。

关键词：直流侧电容电压空间矢量调制三电平逆变器平衡方法混合基础平衡算法功率驱动器

Photometric observations of three high mass X-ray binaries and a search for variations induced by orbital motion

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Research in Astronomy and Astrophysics 2011年第8期11卷 947-964页

作者： Gordon E. Sarty Bogumil Pilecki Daniel E. Reichart Kevin M. Ivarsen Joshua B. Haislip Melissa C. Nysewander Aaron P. LaCluyze Helen M. Johnston Robert R. Shobbrook Lászl L. Kiss Kinwah Wu Departments of Psychology and Physics University of Saskatchewan9 Campus DriveSaskatoonSaskatchewan S7N 5A5Canada Warsaw University Observatory Al. Ujazdowskie 400-478 WarsawPoland Universidad de Concepcion Departamento de AstronomaCasilla 160-CConcepcionChile Department of Physics and Astronomy University of North Carolina-Chapel HillCB 3255Phillips HallChapel HillNC 27599-3255USA School of Physics A28 University of SydneyNew South Wales 2006Australia Konkoly Observatory H-1525 BudapestP.O. Box 67Hungary Mullard Space Science Laboratory University College LondonHolmbury St. MaryDorkingSurrey RH5 6NTUnited Kingdom

We searched for long period variation in V-band, It-band and RXTE X-ray light curves of the High Mass X-ray Binaries （HMXBs） LS 1698 / RX J1037.5-5647, HD 110432 / 1H 1249-637 and HD 161103 / RX J1744.7-2713 in an attempt to discover orbitally induced variation. Data were obtained primarily from the ASAS database and were supplemented by shorter term observations made with the 24- and 40-inch ANU telescopes and one of the robotic PROMPT telescopes. Fourier periodograms suggested the existence of long period variation in the V-band light curves of all three HMXBs, however folding the data at those periods did not reveal convincing periodic variation. At this point we cannot rule out the existence of long term V-band variation for these three sources and hints of longer term variation may be seen in the higher precision PROMPT data. Long term V-band observations, on the order of several years, taken at a frequency of at least once per week and with a precision of 0.01 mag, therefore still have a chance of revealing long term variation in these three HMXBs.

关键词： accretion -- stars: Be stars -- stars: neutron stars -- stars: individual LS 1698 HD 110432 HD 161103 -- X-rays: binaries