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Is hamstrings-to-quadriceps torque ratio useful for predicting anterior cruciate ligament and hamstring injuries?A systematic and critical review

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Journal of Sport and Health Science 2023年第3期12卷 343-358页

作者： Eleftherios Kellis Chrysostomos Sahinis Vasilios Baltzopoulos laboratory of Neuromechanics Department of Physical Education and Sport Sciences at SerresAristotle University of ThessalonikiSerres 62100Greece Research Institute for Sport and Exercise Sciences(RISES) Faculty of ScienceLiverpool John Moores UniversityLiverpool L35UXUK

Background:For the past 30 years,the hamstring(H)-to-quadriceps(Q)(H:Q)torque ratio has been considered an important index of muscle strength imbalance around the knee *** purpose of this systematic review was to examine the value of H:Q torque ratio as an independent risk factor for hamstring and anterior cruciate ligament(ACl)***:Database searches were performed to identify all relevant articles in PubMed,MEDlINE,Cochrane library,and *** studies evaluating the conventional(concentric H:Q),functional(eccentric H:concentric Q),and mixed(eccentric H at 300/s:concentric Q at2400/s)H:Q ratios as risk factors for occurrence of hamstring muscle strain or ACl injury were *** of bias was assessed using the Quality In Prognosis Studies ***:Eighteen included studies reported 585 hamstrings injuries in 2945 participants,and 5 studies documented 128 ACl injuries in *** evidence synthesis analysis indicated that there is very limited evidence that H:Q strength ratio is an independent risk factor for hamstring and ACl injury,and this was not different between various ratio *** limitations and limited evidence for ACl injuries and some ratio types might have influenced these ***:The H:Q ratio has limited value for the prediction of ACl and hamstring *** strength imbalances along with other modifiable factors during the entire competitive season may provide a better understanding of the association between H:Q ratio and injury.

关键词： ACl Isokinetic Prospective Strains Strength imbalance

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连续进水、恒水位的改进型SBR系统

中国给水排水 2001年第7期17卷 17-22页

作者：吴卫国 Peter l.Timpany 加拿大Stantec consulting Internationalltd.

介绍了一种连续进水、恒水位的改进型SBR系统在生物脱氮除磷方面的应用及其动态模拟 ,讨论了该系统的动态模拟在工程设计中的应用及其数学模型基础 ,并通过工程实例解说了在满足不同出水要求方面的设计灵活性。生产规模系统自 1995年以... 详细信息

介绍了一种连续进水、恒水位的改进型SBR系统在生物脱氮除磷方面的应用及其动态模拟 ,讨论了该系统的动态模拟在工程设计中的应用及其数学模型基础 ,并通过工程实例解说了在满足不同出水要求方面的设计灵活性。生产规模系统自 1995年以来的运转实践表明 :运行可靠、操作简便、处理效果好。在加拿大寒冷气候条件下 ,年平均BOD5、总氮、总磷和TSS的去除率分别为 97%、81%、88%和 94 %。该改进型SBR系统的另一特点为剩余污泥浓度高 ,平均约为 2×10 4 mg/l ,这意味着与传统连续进水活性污泥工艺相比。

关键词：改进型SBR 脱氮连续进水除磷恒水位污泥处理

Identification and imaging of soil and soil-pile deformation in the presence of liquefaction

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Earthquake Engineering and Engineering Vibration 2006年第2期5卷 171-182页

作者： M. Zeghal P. V. Kallou C. Oskay T. Abdoun M. K. Sharp Dept. of Civ.and Env. Engrg. Rensselar Polytechnic Institute Troy NY l2l80 USA Mueser Rutledge consulting Engineers 225 W 34th Street New York NY 10122 USA Engineer Dept. of Civ. and Env. Engrg. Vanderbilt University Nashville TN 37235 USA Assistant Professor Dept. of Civ.and Env. Engrg. Rensselar Polytechnic Institute Troy NY l2l80 USA Associate Professor Centrifuge Research & Development Center Vicksburg MS 39180 USA Director

A simple identification technique is developed to visualize the dynamic deformation mechanisms of centrifuge models of saturated soil and soil-pile systems using the measurements provided by sparsely distributed sensors. Crosscorrelation analyses are employed first to assess the variation of shear wave velocity profile with time as soil experiences stiffness reduction and degradation during dynamic excitations. The corresponding time-dependent modal configurations are determined using the finite-element technique. These configurations are used along with recorded motions to evaluate optimal time histories of displacement and strain fields based on a spectral motion reconstruction. Visualizations of the response of infinite slope and soil-pile centrifuge models revealed salient and complex multi-dimensional deformation patterns, especially at high pore pressure ratios. The developed technique provides an effective tool to visualize and analyze the dynamic response of centrifuge, shake-table and field soil systems.

关键词： soil dynamics liquefaction visualization centrifuge model

Mercury bioaccumulation in aquatic biota along a salinity gradient in the Saint john River estuary

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Journal of Environmental Sciences 2018年第6期30卷 41-54页

作者： Bethany l.Reinhart Karen A.Kidd R.Allen Curry Nelson J.O’Driscoll Scott A.Pavey Department of Biology and Canadian Rivers Institute University of New Brunswick Saint John Saint John New Brunswick E2L4L5 Canada Department of Biology Forestry and Environmental Management and Canadian Rivers Institute University of New Brunswick Fredericton New Brunswick E3B4A3 Canada Department of Earth and Environmental Sciences Acadia University Wolfville Nova Scotia B4P2R6 Canada Department of Biology and School of Geography & Earth Sciences McMaster University Hamilton Ontario LSS 4K1 Canada

Although estuaries are critical habitats for many aquatic species, the spatial trends of toxic methylmercury（MeHg） in biota from fresh to marine waters are poorly understood. Our objective was to determine if MeHg concentrations in biota changed along a salinity gradient in an estuary. Fourspine Stickleback（Apeltes quadracus）, invertebrates（snails,amphipods, and chironomids）, sediments, and water were collected from ten sites along the Saint john River estuary, New Brunswick, Canada in 2015 and 2016, with salinities ranging from 0.06 to 6.96. Total mercury（proxy for MeHg） was measured in whole fish and MeHg was measured in a subset of fish, pooled invertebrates, sediments, and water. Stable sulfur（δ34S）, carbon（δ13 C）, and nitrogen（δ15N） isotope values were measured to assess energy sources（S, C） and relative trophic level（N）. There were increases in biotic δ13C and δ34S from fresh to more saline sites and these measures were correlated with *** aqueous MeHg was higher at the freshwater than more saline sites, only chironomid MeHg increased significantly with salinity. In the Saint john River estuary, there was little evidence that MeHg and its associated risks increased along a salinity gradient.

关键词： Stickleback Amphipod Methylmercury Biomagnification Stable isotopes Food web

Emergency logistics Management for Hazardous Materials with Demand Uncertainty and link Unavailability

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Journal of Systems Science and Systems Engineering 2023年第2期32卷 175-205页

作者： Ginger Y.Ke James H.Bookbinder Faculty of Business Administration Memorial University of NewfoundlandSt.John’sNewfoundland and LabradorA1B 3X5Canada Department of Management Sciences University of WaterlooWaterlooOntarioN2L 3G1Canada

Due to its harmful nature,any incident associated with hazardous material(hazmat)may cause tremendous impacts on the surrounding people and the *** on the incident involving this specific type of good,we develop a reliable and robust emergency logistics network that considers both demand uncertainty and possible unavailability of particular links.A time-based risk measure is carefully designed upon the traditional risk assessment to reflect the stakeholder’s sensitivity to risk over response *** disruption and uncertainty are modeled as two sets of scenarios which are integrated into a bi-objective robust model to evaluate the trade-offs between risk and *** effectiveness of the emergency response can be assured by expenditures that add extra capacities to certain links or establish additional facilities that aid recovery from *** apply our model and approach to a real-world network in Guangdong *** results reveal the necessity of embedding consideration of uncertainty and unreliability into emergency network design problems;outline the importance of hedging against unpredictability by system redundancies;and indicate the impact of stakeholder’s orientation towards cost and risk on the location,allocation,and routing decisions in hazmat emergency response.

关键词： Emergency response hazardous materials robust optimization link disruption emergency demand uncertainty

Stand management optimization——the role of simplifications

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Forestry Studies in China 2014年第1期16卷 12-22页

作者： Timo Pukkala Erkki lhde Olavi laiho Faculty of Science and Forestry University of Eastern Finland Joen Forest Program consulting

Background:Studies on optimal stand management often make simplifications or restrict the choice of treatments,Examples of simplifications are neglecting natural regeneration that appears on a plantation site,omitting advance regeneration in simulations,or restricting thinning treatments to low thinning(thinning from below).Methods:This study analyzed the imparts of simplifications on the optimization results for Fennoscandian boreal *** of pine and spruce plantations was optimized by gradually reducing the number of simplifying ***:Forced low thinning,cleaning the plantation from the natural regeneration of mixed species and ignoring advance regeneration all had a major impact on optimization *** thinning(thinning from above) resulted in higher NPV and longer rotation length than thinning from *** was profitable to leave a mixed stand in the tending treatment of young *** advance regeneration was taken into account,it was profitable to increase the number of thinnings and postpone final *** the optimal management,both pine and spruce plantation was gradually converted into uneven-aged mixture of spruce and ***:The results suggest that,with the current management costs and timber price level,it may be profitable to switch to continuous cover management on medium growing sites of Fennoscandian boreal forests.

关键词： Plantation management Continuous cover forestry Even-aged management Mixed stands

“RAISING THE BAR”IN TOIlET PERFORMANCE

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Journal of Green Building 2006年第2期1卷 77-85页

作者： Bill Gauley john Koehler Veritec consulting Inc.1495 Bonhill Rd.Unit 12MississaugaON L5T 1M2 Koeller and Company 5962 Sandra DriveYorba LindaCA 92886-5337

INTRODUCTION There are generally two phases in the consumer’s purchasing process,at least insofar as plumbing fixtures are concerned—the research and decision phase,and the purchase *** consumers may be content to expend considerable energy and time researching and investigating the various pros and cons associated with each product model considered,once they have actually made their purchase,they expect that product to perform as *** do not anticipate expending any more energy wondering about the performance of the product.

关键词： product. phase. concerned

Height increment of understorey Norway spruces under different tree canopies

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Forestry Studies in China 2014年第1期16卷 23-30页

作者： Olavi laiho Timo Pukkala Erkki lhde1 Joen Forest Program consulting Faculty of Science and Forestry University of Eastern Finland

Background:Stands having advance regeneration of spruce are logical places to start continuous cover forestry(CCF) in fertile and mesic boreal ***,the development of advance regeneration is poorly ***:This study used regression analysis to model the height increment of spruce understorey as a function of seedling height,site characteristics and canopy ***:An admixture of pine and birch in the main canopy improves the height increment of *** the stand basal area is 20 m2ha-1 height increment is twice as fast under pine and birch canopies,as compared to *** increment of understorey spruce increases with increasing seedling ***-stand and within-stand residual variation in the height increment of understorey spruces is *** increment of 1/6 fastest-growing seedlings is at least 50%greater than the ***:The results of this study help forest managers to regulate the density and species composition of the stand,so as to obtain a sufficient height development of the *** pure and almost pure spruce stands,the stand basal area should be low for a good height increment of the understorey.

关键词： Advance regeneration Continuous cover forestry Growth model Picea abies Uneven-aged management

Fertilizer-Induced Advances in Corn Growth Stage and Quantitative Definitions of Nitrogen Deficiencies

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Pedosphere 2008年第1期18卷 60-68页

作者： J. ZHANG A. M. blackMER P. M. KYVERYGA B. W. VAN DE WOESTYNE T. M. blackMER Department of Agronomy Iowa State University Ames IA 50011 (USA) Iowa Soybean Association 4554 114th Street Urbandale IA 50322 (USA) john Deere Ag Management Solutions 140 114th Street Urbandale IA 50322 (USA) Statistieal consulting Center 130 MM Wright State University Dayton OH 45435 (USA)

Evidence that nitrogen (N) fertilization tends to accelerate maturation as well as increase rates of growth has received little attention when diagnosing N deficiencies in corn (Zea mays l.).Such a tendency could be a potential source of errors when the diagnosis is solely based on comparing plants with different rates of *** N fertilization could accelerate rates of growth and maturation was tested in a field study with 12 paired plots representing relatively large variability in soil properties and landscape *** plots were located under conditions where preplant N fertilization reduced or avoided temporary N shortages for some plants but did not reduce for other plants early in the *** measured corn heights to the youngest leaf collar,stages of growth and chlorophyll meter readings (CMRs). The added N advanced growth stages as well as increased corn heights and CMRs at any given *** effects on corn heights,growth stages and ear weights were statistically significant (Pl variability associated with *** in growth due to a temporary shortage of N within a growth stage might be partially offset by longer periods of growth within that stage to physiological *** shortages of N,therefore,may produce symptoms of N deficiency in situations where subsequent additions of N should not be expected to increase *** of these two somewhat different effects (i.e.,increase growth rates and advance growth stages) on corn growth could help to define N deficiency more precisely and to improve the accuracy of diagnosing N status in production agriculture.

关键词： chlorophyll corn fertilizer growth stage nitrogen deficiency