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Association of 25-hydroxy-vitamin D levels with semen and hormonal parameters

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Asian Journal of Andrology 2012年第6期14卷 855-859页

作者： Ahmad O Hammoud A Wayne meikle C matthew peterson Joseph Stanford mark Gibson Douglas T Carrell Division of Reproductive Endocrinology and Infertility University of Utah Salt Lake City UT 84108 USA Division of Endocrinology Metabolism and Diabetes Department of Internal Medicine University of Utah School of Medicine Salt Lake City UT 84108 USA ARUP Institute for Clinical and Experimental Pathology Salt Lake City UT 84108 USA Department of Preventive and Family medicine University of Utah Salt Lake City UT 84108 USA Department of Surgery (Urology) and Physiology Andrology and IVF Laboratories University of Utah Salt Lake City UT 84108 USA

Vitamin D levels have been linked to various health outcomes including reproductive disorders. The purpose of this study was to explore the association between serum vitamin D level （25-hydroxy-vitamin D, or 250HD） and semen and hormonal parameters. This is a cross-sectional study that included 170 healthy men recruited for the study of spermatogenesis from the general population. men completed general and reproductive health questionnaires, and donated blood and semen samples. The main measures were hormonal （total and free testosterone, sex hormone-binding globulin, estradiol, follicle-stimulating hormone and luteinizing hormone） and semen parameters, adjusted （n= 147） for age, body mass index （BmI）, season, alcohol intake and smoking, in relation to categories of vitamin D levels, determined apriori. The mean age of the study population was 29.0±8.5 years and mean BmI was 24.3±3.2 kg m-2. The mean 250HD was 34.1± 15.06 ng m1-1. BmI showed a negative association with 250HD. Sperm concentration, sperm progressive motility, sperm morphology, and total progressively motile sperm count were lower in men with ‘250HD ≥ 50 ng ml-1＇ when compared to men with‘20 ng ml-1 ≤ 250H D〈 50 ng ml-1,. Total sperm count and total progressive motile sperm count were lower in men with ‘250HD〈20 ng ml-1＇ when compared to men with‘20 ng ml-1≤250HD〈50 ng ml-1＇. The adjusted means of various hormonal parameters did not show statistical difference in the different categories of 250HD. In conclusion, serum vitamin D levels at high and low levels can be negatively associated with semen parameters.

关键词： low semen count obesity semen parameters vitamin D

Strain Energy Release from the 2011 9.0 mw Tōhoku Earthquake, Japan

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Open Journal of Earthquake Research 2013年第4期2卷 75-83页

作者： Kenneth m. Cruikshank Curt D. peterson Department of Geology Portland State University Portland USA

The purpose of this paper is to compare the strain energy released due to elastic rebound of the crust from the tragic 2011 9.0 mwTōhoku earthquake in Japan with the observed radiated seismic energy. The strain energy was calculated by analyzing coseismic displacements of 1024 GPS stations of the Japanese GEONET network. The value of energy released from the analysis is 1.75 × 1017J, which is of the same order of magnitude as the USGS-observed radiated seismic energy of 1.9 × 1017Nm (J). The strain energy method is independent of seismic methods for determining the energy released during a large earthquake. The analysis shows that although the energy release is concentrated in the epicentral region, about 12% of the total energy was released throughout the Japanese islands at distances greater than 500 km west of the epicenter. Our results also show that outside the epicentral region, the strainenergy was concentrated along known tectonic zones throughout Japan.

关键词： Japan Earthquake Crustal Strain GPS Radiated Energy

Late Stage Interseismic Strain Interval, Cascadia Subduction Zone margin, USA and Canada

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Open Journal of Earthquake Research 2017年第1期6卷 1-34页

作者： Kenneth m. Cruikshank Curt D. peterson Department of Geology Portland State University Portland OR USA

modern horizontal strain (2006-2016) measured along 56 new and 108 previously published GPS station baselines are used to establish the length (800 km) and width (300 - 400 km) of the central Cascadia convergent margin seismogenic structure. Across-margin (west-east) annual rates of shortening range from 10﹣9 a﹣1 at the eastern (landward) limit of the central Cascadia seismogenic structure to 10﹣7 a﹣1 along the western onshore portion of the interplate zone. Relatively high shortening strain rates (10﹣8 a﹣1 to 10﹣7 a﹣1) are also measured in western transects from the northern (Explorer plate) and southern (Gorda plate) segments of the convergent margin, demonstrating that the full length of the margin (1300 km length) is currently capable of sustaining and/or initiating a major great earthquake. Vertical GPS velocities are averaged over the last decade at 321 stations to map patterns of uplift (0 - 5 mm yr﹣1) and subsidence (0 - 9 mm yr﹣1) relative to the study area mean. Along-margin belts of relative uplift and subsidence, respectively, are approximately associated with Coast Ranges and the Cascade volcanic arc. However, the vertical velocity data are locally heterogeneous, demonstrating patchy “anomalies” within the larger along-margin belts. A large coastal subsidence anomaly occurs in southwest Washington where the modern short-term trend is reversed from the long-term (~200 yr) tidal marsh record of coastal uplift since the last co-seismic subsidence event (AD1700). The modern vertical displacements represent a late stage of the current inter-seismic interval. If the horizontal strain is considered largely or fully elastic, extrapolating the modern strain rates over the last 100 years show the accumulated strains would be similar in magnitude to the observed co-seismic strains resulting from the Tōhoku, Japan, mw 9.0 earthquake in 2011. We believe that the central Cascadia seismogenic structure has accumulated sufficient elastic strain energy, during the last

关键词： Convergent margin Cascadia Strain Strain-Energy GPS

Selective Activation of Intrinsic Cohesive Elements

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Journal of Applied mathematics and Physics 2014年第12期2卷 1061-1068页

作者： Kyeongsik Woo William m. peterson Douglas S. Cairns School of Civil Engineering Chungbuk National University Cheongju Chungbuk Korea Department of mechanical & Industrial Engineering Montana State University Bozeman MT USA

In this paper, a selective activation strategy is studied in order to alleviate the issue of added compliance in the intrinsic cohesive zone model applied to arbitrary crack propagation. This strategy proceeds by first inserting cohesive elements between bulk elements and subsequently tying the duplicated nodes across the interface using controllable multi-point constraints before the analysis begins. Then, during the analysis, a part of the multi-point constraints are selectively released, thereby reactivating the corresponding cohesive elements and allowing cracks to initiate and propagate along the bulk element boundaries. The strategy is implemented in Abaqus/Standard using a user-defined multi-point constraint subroutine. Analysis results indicate that the strategy significantly alleviates the added compliance problem and reduces the computation time.

关键词： Intrinsic CZm Arbitrary Crack Propagation Added Compliance Selective Activation multi-Point Constraint

(U-Th)/He技术约束下库车盆地北缘构造热演化——以吐孜2井为例

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地球物理学报 2014年第1期57卷 62-74页

作者：喻顺陈文吕修祥 Noreen Evans brent mcInnes 尹继元孙敬博李洁中国地质科学院地质研究所同位素热年代学实验室北京100037 大陆构造与动力学国家重点实验室北京100037 中国石油大学(北京)地球科学学院北京1022494 John De Laeter Center for Isotope Research Applied Geology/Applied PhysicsCurtin University

库车前陆盆地蕴藏着丰富的油气资源,然而盆地中新生代的构造热演化史一直缺乏有效的研究,制约了油气的勘探.本文测试了吐孜2井磷灰石、锆石(U-Th)/He年龄数据,建立了He年龄随现今温度/深度变化的关系,确定该区磷灰石(U-Th)/He体系封闭... 详细信息

库车前陆盆地蕴藏着丰富的油气资源,然而盆地中新生代的构造热演化史一直缺乏有效的研究,制约了油气的勘探.本文测试了吐孜2井磷灰石、锆石(U-Th)/He年龄数据,建立了He年龄随现今温度/深度变化的关系,确定该区磷灰石(U-Th)/He体系封闭温度为89℃.综合利用(U-Th)/He及镜质体反射率(Ro)数据模拟恢复了库车盆地吐孜2井中新生代热演化史,结果表明库车盆地吐孜洛克背斜形成起始时间约为5ma,新生代抬升剥蚀量平均约为670m,平均抬升剥蚀速率为0.133mm/a.根据新生代吐孜洛克背斜的构造演化分析确定了气源断裂活动及圈闭形成的时期,揭示了吐孜洛克背斜天然气成藏时间为5ma以后,且烃源岩生排烃、断裂活动及圈闭形成的时间具有良好的匹配关系,这是吐孜洛克油气田形成的关键因素之一.本文应用(U-Th)/He技术研究沉积盆地构造热演化史,对库车盆地油气勘探具有重要的意义.

关键词： He封闭温度构造热演化隆升剥蚀库车盆地

Typhoon frequency and intensity across the Western Pacific Ocean north of the Equator, 1951 – 2014

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中国科学数据（中英文网络版） 2017年第4期2卷 40-49页

作者： A.Townsend peterson Lindsay P.Campbell Rafe m.Brown Biodiversity Institute University of KansasLawrenceKansas 66045USA

Disturbance has been a repeated theme in ecology in recent decades,yet incorporating its frequency and pattern at broad spatial scales into ecological analyses has been difficult-rather,most environmental datasets used in broad-extent analyses represent average *** present a detailed dataset summarizing the frequency(i.e.,number of typhoons)and intensity(average and maximum windspeeds)of typhoons across the Western Pacific north of the Equator,based on data characterizing tracks for 1673 typhoons from the Japan meteorological *** data presented are aggregated and resampled to 0.2°(~22 km at the Equator)spatial resolution;temporal coverage extends *** also present data specifically for prior to 1980 and after 1999,to respond to questions related to climate change,although no major changes were evident between the time periods.

关键词： typhoon disturbance Western Pacific maps

Joint Contact Forces with Changes in Running Stride Length and midsole Stiffness

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Journal of Science in Sport and Exercise 2020年第1期2卷 69-76页

作者： Joshua m.Thomas Wbrent Edwards Timothy R.Derrick Department of Health Wellnessand SportUniversity of DubuqueDubuqueIA 52001USA Human Performance Laboratory Faculty of KinesiologyUniversity of CalgaryCalgaryAB T2N 1N4Canada Department of Kinesiology Iowa State University111L Forker BuildingAmesIA 50011USA

The purpose of this study was to determine if lower extremity joint loading was influenced by stride length or shoe midsole *** subjects completed 10 trials of overground running at an average speed of 4.43 m/s in each of three condi-tions:normal running,running with a stride length(SL)reduced by 10%of normal,and running with a cushioned midsole stiffness(i.e.,mechanical impact reduction of 13.7-10.9 g).Reaction forces calculated from inverse dynamics were summed with muscle forces estimated from a musculoskeletal model using static optimization to obtain joint contact forces at the hip,knee and ankle *** components of the contact forces[axial,anterior-posterior,and medial-lateral(mL)]were examined using parametric statistics(α=0.05).Reducing stride length resulted in significant decreases in absolute peak ankle contact forces in the axial direction(normal:-14.5±1.5 BW;reduced SL:-14.0±1.6 BW)and the mL direction(normal:0.67±0.23 BW;reduced SL:0.61±0.21 BW).Reducing stride length also reduced the peak absolute axial forces at the knee(normal:-10.6±1.3 BW;reduced SL:-9.8±1.2 BW)and the hip(normal:-7.26±2.24 BW;reduced SL:-6.75±2.10 BW).The cushioned shoe did not statistically reduce the peak absolute contact forces from the normal stride condition at any of the *** hoc stress analysis suggested that the observed changes in anterior hip force would increase stress more than any of the other statistically significant *** in stride length appear to decrease some joint contact variables but cushioning in the heel region of the shoe does not.

关键词： Gait Injury Compressive force Shear force Cushioning Strain

Two-dimensional titanium carbonitride mXene as a highly efficient electrocatalyst for hydrogen evolution reaction

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materials Reports(Energy) 2022年第1期2卷 88-95页

作者： Kun Liang Anika Tabassum manish Kothakonda Xiaodong Zhang Ruiqi Zhang Brianna Kenney brent D.Koplitz Jianwei Sun michael Nagui Department of Physics and Engineering Physics Tulane UniversityNew OrleansLA70118USA Department of Chemistry Tulane UniversityNew OrleansLA70118USA

In this paper,we report,for the first time,on the electrochemical catalytic activity of 2D titanium carbonitride mXene for hydrogen evolution reaction(HER).According to our study,2D titanium carbonitride exhibited much higher electrocatalytic activity than its carbide analogues,achieving an onset overpotential of 53 mV and Tafel slope of 86 mV dec^(-1),superior to the titanium carbide with onset overpotential of 649 mV and Tafel slope of 303 mV dec^(-1).The obtained onset overpotential for 2D titanium carbonitride is lower than those of all the reported transition metal carbides mXene catalysts without additives,so *** functional theory calculations were conducted to further understand the electrochemical *** calculation results show that a greater number of occupied states are active for Ti_(3)CNO_(2),revealing free energy for the adsorption of atomic hydrogen closer to 0 than that of Ti_(3)C_(2)O_(2).Both experimental and calculation studies demonstrate the excellent electrocatalytic behavior of titanium *** investigation of 2D titanium carbonitride opens up a promising paradigm for the conscious design of high-performance non-precious metal catalyst for hydrogen generation.

关键词： Two-dimensional Titanium carbonitride mXene Nanosheets Hydrogen evolution Electrocatalyst Density functional theory calculation

SPATIALLY DISTRIBUTED WATER SURFACE TEmPERATURE mODELING FOR THE GREAT LAKES

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气象科学 2000年第3期20卷 427-432页

作者： Yongchun Zhuu (Cooperative Institute for Limnology and Ecosystem Research,University of michigan,Ann Arbor,michigan) brent m.Lofgren (Great Lakes Environmental Research Laboratory,Ann Arbor,michigan) Cooperative Institute for Limnology and Ecosystem Research Universit y of MichiganAnn ArborMichigan Great Lakes Environmental Research Laboratory Ann ArborMichigan

This paper describes the development and validation of a water temperature model for the Great *** model is keyed to simulate horizontally and temporally varying surface *** ice cover model is coupled with the water temperature model,forming a spatially distributed thermodynamic model for the Great *** model can be used to give long term or short term simulations of water surface temperature and ice cover for the Great Lakes.

关键词： Water surface Temperature modeling