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Efficient Orbit Propagation of Orbital Elements Using Modified Chebyshev Picard Iteration Method

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Computer Modeling in Engineering & Sciences 2016年第1期111卷 65-81页

作者： j.L.read A.Bani Younes j.L.junkins Graduate Research Assistant Texas A&M UniversityCollege StationTXUSA. Assistant Professor Khalifa UniversityAbu DhabiUAE. Distinguished Professor Texas A&M UniversityCollege StationTXUSA.

This paper focuses on propagating perturbed two-body motion using orbital elements combined with a novel integration *** previous studies show that Modified Chebyshev Picard Iteration(MCPI)is a powerful tool used to propagate position and velocity,the present results show that using orbital elements to propagate the state vector reduces the number of MCPI iterations and nodes required,which is especially useful for reducing the computation time when including computationally-intensive calculations such as Spherical Harmonic gravity,and it also converges for>5.5x as many revolutions using a single segment when compared with cartesian *** for the Classical Orbital Elements and the Modified Equinoctial Orbital Elements(the latter provides singularity-free solutions)show that state propagation using these variables is inherently well-suited to the propagation method *** benefits are achieved using a segmentation scheme,while future expansion to the two-point boundary value problem is expected to increase the domain of convergence compared with the cartesian *** is an iterative numerical method used to solve linear and nonlinear,ordinary differential equations(ODEs).It is a fusion of orthogonal Chebyshev function approximation with Picard iteration that approximates a long-arc trajectory at every *** studies have shown that it outperforms the state of the practice numerical integrators of ODEs in a serial computing environment;since MCPI is inherently massively parallelizable,this capability is expected to increase the computational efficiency of the method presented.

关键词： Propagation Integration Orbital Mechanics Classical Elements Modified Equinoctial Chebyshev Picard Iteration MCPI Polynomials Initial Value Problem IVP.

Enhancements to Modified Chebyshev-Picard Iteration Efficiency for Perturbed Orbit Propagation

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Computer Modeling in Engineering & Sciences 2016年第1期111卷 29-64页

作者： B.Macomber A.B.Probe R.Woollands j.read j.L.junkins Texas A&M University College StationTXUSA.

Modified Chebyshev Picard Iteration is an iterative numerical method for solving linear or non-linear ordinary differential *** a serial computational environment the method has been shown to compete with,or outperform,current state of practice numerical *** paper presents several improvements to the basic method,designed to further increase the computational efficiency of solving the equations of perturbed orbit propagation.

关键词： Astrodynamics Orbit Propagation Cheybshev Polynomials Picard Iteration.

Aboveground resilience to species loss but belowground resistance to nitrogen addition in a montane plant community

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journal of Plant Ecology 2018年第3期11卷 351-363页

作者： Quentin D.read jeremiah A.Henning Aimée T.Classen Nathan j.Sanders Department of Ecology and Evolutionary Biology University of Tennessee569 Dabney HallKnoxvilleTN 37996USA Rocky Mountain Biological Laboratory PO Box 615Crested ButteCO 81224USA Center for Macroecology Evolutionand ClimateNatural History Museum of DenmarkUniversity of CopenhagenUniversitetsparken 152100 CopenhagenDenmark Rubenstein School of Environment and Natural Resources University of VermontBurlingtonVT 05405USA

Aims Decades of empirical work have demonstrated how dominant plant species and nitrogen fertilization can influence the structure and function of plant *** recent studies have examined the interplay between these factors,but few such studies use an explicit trait-based *** this study,we use an explicit trait-based approach to identify potential mechanisms for community-level responses and to test ecological niche *** We experimentally manipulated plant communities(control,−dom-inant species,−random biomass)and nitrogen(N)inputs(control,+organic N,+inorganic N)in a fully factorial *** predicted that traits related to plants’ability to take up different forms of soil N would differ between dominant and subordinate species,resulting in interactive effects of dominant species loss and N fertilization on plant community structure and *** study took place in a montane meadow in the Rocky Mountains,Colorado,*** Findings After four years,the plant community in removal plots converged toward a species composition whose leaf and root functional traits resembled those of the previously removed dominant *** productivity generally increased with N addition:soil carbon efflux was~50%greater when either form of N was added,while inorganic N addition increased aboveground biomass pro-duction by~60%relative to *** increase in production was mediated by increased average height,leaf mass:area ratio and leaf dry matter content in plant communities to which we added inorganic *** to our predictions,there were no interactive effects of N fertilization and dominant species loss on plant com-munity structure or ecosystem *** plant community com-position in this study exhibited resistance to soil N addition and,given the functional convergence we observed,was resilient to spe-cies ***,our results indicate that the ability of species to compensate functionally for species loss confers

关键词： dominant species fertilization functional trait removal experiment resilience

Soil Organic Carbon Pools Under Switchgrass Grown as a Bioenergy Crop Compared to Other Conventional Crops

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Pedosphere 2013年第4期23卷 409-416页

作者： F.G.DOU F.M.HONS W.R.OCUMPAUGH j.C.read M.A.HUSSEY j.P.MUIR Texas A&M AgriLife Research &Extension Center at Beaumont Department of Soil and Crop Sciences Texas A&M University Texas A&M AgriLife Research Station at Beeville Texas A&M AgriLife Research and Extension Center at Dallas Texas A&M AgriLife Research and Extension Center at Stephenville

Switchgrass （Panicum virgaturn L.） has been proposed as a sustainable bioenergy crop because of its high yield potential, adap- tation to marginal sites, and tolerance to water and nutrient limitations. A better understanding of the potential effects of biomass energy crop production practices on soil biological properties and organic matter dynamics is critical to its production. Our objective was to evaluate changes in C pools under a warm-season perennial switchgrass in different soils compared to typically-grown crops col- lected at College Station, Dallas, and Stephenville, TX in February 2001. Sampling depths were 0-5, 5-15, and 15-30 cm. Switchgrass increased soil organic C （SOC）, soil microbial biomass C （SMBC）, mineralizable C, and particulate organic matter C （POM-C） com- pared to conventional cropping systems. Soil C concentrations were in the order： long-term coastal bermudagrass [Cynodon dactylon （L.） Pers.] 〉 switchgrass or kleingrass （Panicum coloratura L.） planted in 1992 〉 switchgrass 1997 〉 conventional cropping systems. Soil C concentrations tended to increase with increasing clay content. Greater microbial biomass C followed the order of Dallas 〉 College Station 〉 Stephenville, and ranged from approximately 180 mg C kg-1 soil at Stephenville to 1 900 mg C kg-1 soil at Dallas. Particulate organic C was more sensitive than other fractions to management, increasing as much as 6-fold under long-term coastal bermudagrass compared to conventional cropping systems. Our study indicated that conversion of conventional cropping systems into switchgrass production can sequestrate more SOC and improve soil biological properties in the southern USA.

关键词： cropping systems particulate organic C perennial grasses soil microbial biomass C soil mineralizable C

The Effects of a Four-Week Neuromuscular Training Program on Landing Kinematics in Pre-and Post-Peak Height Velocity Male Athletes

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journal of Science in Sport and Exercise 2021年第1期3卷 37-46页

作者： Paul j.read jon L.Oliver Ian j.Dobbs Megan A.Wong Nakul Tumkur Anil Kumar Rhodri S.Lloyd Institute of Sport Exercise and HealthUniversity College LondonLondonUK School of Sport and Exercise University of GloucestershireGloucesterUK School of Sport and Health Sciences Cardiff Metropolitan UniversityCardiffUK Sport Performance Research Institute New Zealand(SPRINZ)AUT UniversityAuckland Centre for Sport Science and Human Performance Waikato Institute of TechnologyHamiltonNew Zealand

Purpose Neuromuscular training aims to enhance motor skill competency and increase muscle ***,the effectiveness of short-duration interventions focused on addressing lower limb injury risk factors in male youth athletes at different stages of maturity remains *** Forty-eight young male academy cricket players[pre-peak height velocity(PHV)(n=26)and post-PHV(n=22)]were subdivided into an experimental group(EXP)who completed a 4-week progressive neuromuscular training program and controls(CON)participating in sport training *** in injury risk were examined using the Tuck jump Assess-ment(TjA)and Landing Error Scoring System(LESS).Results Total LESS score was significantly lower in both EXP maturity groups compared to CON following the 4-week program(10 to 6 and 6 to 4(~20%to 40%))in the pre-and post-PHV EXP groups,*** within-group reductions in total LESS score were shown for the pre-PHV EXP group only(PjA total score were shown in post-PHV(5 to 3;40%)versus pre-PHV EXP(6 to 4.5;26%).Pre-PHV players showed positive changes in individual LESS criteria indicative of frontal plane control but not in knee valgus during the TjA,whereas post-PHV players did improve this *** This study indicates it is possible to reduce TjA and LESS scores in male youth athletes by performing a 4-week neuromuscular training program,improving landing mechanics and reducing injury risk irrespective of maturity,but their effects are somewhat influenced by stage of maturation and the task performed.

关键词： Injury risk Maturation Landing

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碳酸盐岩台地相模式

国外油气勘探 1995年第2期7卷 132-154页

作者： j.Fred read 金福锦物探局地研院

不同类型的碳酸盐岩台地相以不同的外形、沉积相以及演化序列为特征。斜坡可能是单斜的,抑或远端变陡,且可能有裙边或鲕粒砂屑浅水滩坝复合体或者骨屑滩。单斜的斜坡向海方向进入较深的水域,没有明显大陆坡折,且缺少深水角砾岩。远端变... 详细信息

不同类型的碳酸盐岩台地相以不同的外形、沉积相以及演化序列为特征。斜坡可能是单斜的,抑或远端变陡,且可能有裙边或鲕粒砂屑浅水滩坝复合体或者骨屑滩。单斜的斜坡向海方向进入较深的水域,没有明显大陆坡折,且缺少深水角砾岩。远端变陡的斜坡可能系低能量环境,且以浪基面下广布的浅水泥质盖层为特征。若在高能环境下,则可能有海岸沙滩沙丘复合体以及广布的骨骸质砂臂盖层。陆坡相可能拥有丰富的陆坡驱动碎屑所致的角砾岩。镶边的大陆架顶部相对平坦,在高能环境下具有明显的坡折。浅水大陆架边端经由该坡折便进入深水域。这类大陆架的大部分区域可能有潮缘相加积,也可能被早期淹没,这取决于海平面的起伏幅度。它们可能是加积的,也可能是过水型的,包含有沟蚀斜坡,陡坎以及高起伏的侵蚀形态。某些大陆架上发育有陆架内盆地,这种盆地控制着储集层和生油层的分布。孤立的台地通常被深水包围,它们可能位于断裂的大陆边缘上或者海底火山之上。绝大多数的台地具有高起伏的镶边边缘。经受过海平面迅速上升期的台地可能在早期就被淹没,它们以抬升的边缘,生长的斑礁或塔礁以及广布的浅海碳酸盐岩或细粒碎屑岩盖层为特征。完全淹没的大陆架发育在大陆架沉没到水体了透光深度的地方,且通常终止了浅水沉积作用,一般只形成半深水相的薄盖层。某些边缘显示有广泛的向盆地下掉的断裂作用,同时伴有碳酸盐岩沉积,或者厚层的进积碎屑岩层序。台地相的类型随沉积作用,盆地沉降或海平面上升的变化而异,并可能形成不同的演化序列。这里所介绍的几种模式看来足以包容绝大多数地质实例。其中一些则拥有较重要的储集岩相。

关键词：碳酸盐岩台地模式岩相沉积储集岩油气勘探

In-depth profiling of tumor tissue derived from malignant pleural mesothelioma patients identifies potential biomarkers predicting response to immune-checkpoint inhibitor therapy

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Genes & Diseases 2024年第6期11卷 28-31页

作者： Dmitri Shek Bo Gao Hema Mahajan Adnan Nagrial Matteo S.Carlino Fabio Luciani Scott A.read Golo Ahlenstiel Blacktown Clinical School Western Sydney UniversitySydneyNSW 2148Australia Westmead Institute for Medical Research SydneyNsw 2145Australia Blacktown Mt Druitt Hospital SydneyNSW 2148Australia Westmead Hospital SydneyNsw 2145Australia Westmead Clinical School University of SydneySydneyNSW 2145Australia Institute of Clinical Pathology and Medical Research SydneyNSW 2145Australia Melanoma Institute Australia SydneyNSW 2065Australia School of Medical Sciences University of New South WalesSydneyNSW 2052Australia Garvan Institute for Medical Research SydneyNSW 2010Australia

Malignant pleural mesothelioma(MPM)is a rare and aggressive cancer with low survival probability as it is generally diagnosed at later stages.'Using a combination of immune-checkpoint inhibitors(ICls)ipilimumab(IPl)and nivolumab(NivO)as a first-line treatment for unresectable MPM,the CheckMate 743 trial reported higher overall survival and prolonged duration of response compared with traditional chemotherapy.

关键词： pleural chemotherapy immune

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疝病学：历史现状和未来

中国实用外科杂志 2010年第7期30卷 558-561页

作者： read R C University of Arkansas for Medical Sciences 304 Potomac Street Rockville MD 20850 USA

疝修补术是一种常见手术,大多数医生认为这是一种小手术。但是有些医生却不这么认为。疝修补术的创造者是Bassini(1884),他发明了腹股沟疝的根治性治疗方法:切开腹股沟的三层,即腹内斜肌、腹横肌、腹横筋膜,进入了腹膜前间隙,以高位结... 详细信息

疝修补术是一种常见手术,大多数医生认为这是一种小手术。但是有些医生却不这么认为。疝修补术的创造者是Bassini(1884),他发明了腹股沟疝的根治性治疗方法:切开腹股沟的三层,即腹内斜肌、腹横肌、腹横筋膜,进入了腹膜前间隙,以高位结扎疝囊和以上三层缝合至腹股沟韧带。这种手术方式只有2.7%的复发率,因此引起世界范围内的争相仿效。但同时问题也接踵而至,提睾肌仍然残留,没有切开的层面不缝合,没有重叠加强修补,采用提睾肌或腹直肌加强修补,使用筋膜瓣,减张切开。这种讹误使人们对Bassini的工作产生了怀疑。自1906年采用Russsel(lLancet,1906,2:1197-1203.)的疝囊结扎手术直到1953年。此后Shoudice诊所使Bassini原则重新流行,并被奉为疝修补的金标准而历时数十年。Cheatle引入了后路腹膜前疝修补术(BrMedj,1920,2:68-69)。Acquaviva和Bourret设计了第一个植入假体(尼龙),后来被聚丙烯取代。这些贡献为Rives、Stoppa、Wantz及Gilbert等后来者的修补方法,Ger的腹腔镜修补法以及一些不常见的疝修补术铺平了道路。Chevrel(1979)创建了GREPA,这就是后来的欧洲疝学会,后来又和美国疝学会一起创建了《Hernia》杂志。Nilsson(1993)制定了全国性疝登记制度,致力于更低的复发率和更好的前瞻性研究。在21世纪,Lichtenstein疝修补术逐渐占据主流地位。疝学者接受了系统性结缔组织疾病是腹部疝和盆底脱垂的原因。这种病因可以解释为什么植入物推迟了复发但并没有根除复发。更好的解决方法还有待研究和应用。

关键词：疝病学

SARS-CoV-2 inhibition and specific targeting of infected cells by VSV particles carrying the ACE2 receptor

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Signal Transduction and Targeted Therapy 2023年第6期8卷 2463-2466页

作者： Fabian Zech Stefanie Weber Hanna Dietenberger Linyun Zhang Sabrina Noettger Meta Volcic Tim Bergner Clarissa read Konstantin M.j.Sparrer Thomas F.E.Barth Frank Kirchhoff Institute of Molecular Virology Ulm University Medical CenterUlmGermany Institute of Pathology Ulm UniversityUlmGermany Central Facility for Electron Microscopy Ulm UniversityUlmGermany

Dear Editor Effective vaccines and some antiviral agents against SARS-CoV-2,the causative agent of coronavirus disease 2019(COVID-19),have been ***,additional therapeutics are needed since emerging SARS-CoV-2 variants evade immunity induced by vaccination or previous infection and are resistant to therapeutic antibodies and fusion inhibitors.^(1)In addition,many patients experience prolonged post-acute sequelae of SARS-CoV-2.

关键词： ACE2 immunity acute