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journal of Central south University 2011年第1期18卷 250-258页

作者：胡小弟 L.f.WALUBITA Texas Transportation Institute Texas A&M University SystemCollege StationTexas 77840-3135USA Transportation Research Center Wuhan Institute of TechnologyWuhan 430073China

A three dimensional finite element program incorporating actually measured vertical tire-pavement contact pressure(TPCP) was utilized for modeling the mechanistic responses in asphalt concrete(AC) layers by simulating various vehicle motions:stationary and non-stationary(*** acceleration or deceleration mode).Analysis of the results indicated the following items.1) It is critical to use the vertical TPCP as the design control criteria for the tensile strains at the bottom of the AC layer when the base layer modulus is lower in magnitude(e.g.≤400 MPa);however,when the base layer modulus is higher in magnitude(e.g.≥7 000 MPa),the horizontal TPCP and the tensile strains in the X-direction at the surface of the AC layer should also be considered as part of the design response criteria.2) The definition of "overload" needs to be revised to include tire pressure over-inflation,i.e.,a vehicle should be considered to be overloaded if the wheel load exceeds the specification and/or the tire inflation pressure is higher than the specification.3) Light trucks have more structural impact on the strain responses and pavement design when the thickness of the surfacing AC layer is thinner(e.g.≤50 mm).4) The acceleration of a vehicle does not significantly impact the AC surface distresses such as rutting at the top of the upgrade slopes or intersections;however,vehicle deceleration can dramatically induce horizontal shear strains and consequently,aggravate shoving and rutting problems at the highway ***,these factors should be taken into account during mechanistic stress-strain modeling and structural design of asphalt pavements.

关键词： asphalt pavement tire-pavement contact pressure vehicle acceleration mechanistic response three-dimensional finiteelement

Verification of a laboratory-based dilation model for in situ conditions using continuum models

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journal of Rock Mechanics and Geotechnical Engineering 2014年第6期6卷 522-534页

作者： G.Walton M.s.Diederichs L.R.Alejano j.Arzúa Queen's University Kingston Canada University of Vigo Vigo Spain

With respect to constitutive models for continuum modeling applications, the post-yield domain remainsthe area of greatest uncertainty. Recent studies based on laboratory testing have led to thedevelopment of a number of models for brittle rock dilation, which account for both the plastic shearstrain and confining stress dependencies of this phenomenon. Although these models are useful inproviding an improved understanding of how dilatancy evolves during a compression test, there hasbeen relatively little work performed examining their validity for modeling brittle rock yield in situ. Inthis study, different constitutive models for rock dilation are reviewed and then tested, in the context of anumber of case studies, using a continuum finite-difference approach （fLAC）. The uncertainty associatedwith the modeling of brittle fracture localization is addressed, and the overall ability of mobilizeddilation models to replicate in situ deformation measurements and yield patterns is evaluated. 2014 Institute of Rock and soil Mechanics, Chinese Academy of sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Dilation Continuum models Case studies Brittle rock

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类固体非晶态材料的变形与失效

力学进展 2021年第2期51卷 406-426页

作者： falk M L Langer j s 陈艳(译) 王云江(校) 约翰霍普金斯大学材料科学与工程系、机械工程系、物理与天文系马里兰州巴尔的摩21218 加州大学物理系加利福尼亚州圣巴巴拉93106-9530 中国科学院力学研究所

自20世纪70年代以来,类固体非晶态材料变形与失效的理论模型相继出现,这些模型基于应力驱动分子重排从而在局部流动缺陷处发生剪切转变这一物理图像.该图像是现代剪切转变区理论的基础,也是本综述的焦点.我们将首先概述该理论框架并给... 详细信息

自20世纪70年代以来,类固体非晶态材料变形与失效的理论模型相继出现,这些模型基于应力驱动分子重排从而在局部流动缺陷处发生剪切转变这一物理图像.该图像是现代剪切转变区理论的基础,也是本综述的焦点.我们将首先概述该理论框架并给出一些应用案例,特别是块体金属玻璃应力−应变测量结果的阐释,剪切带数值模拟分析和剪切转变区运动方程在自由边界计算中的应用.在本综述的第二部分,为简单起见,将关注非晶塑性的非热模型,并基于该模型说明剪切转变区理论是如何从非平衡热力学的系统描述中发展起来的.

关键词：塑性非平衡热力学剪切转变区

Chronic hepatitis C infection in a patient with bone marrow hypoplasia

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World journal of Gastroenterology 2008年第26期14卷 4238-4240页

作者： s Bethlen K Chandrikakumari L de Leval jB Giot D Mukeba P Leonard f frippiat C Meuris j Delwaide M Moutschen Centre Hospitalier Universitaire de Liege Liege 4000Belgium Medical Student Department of Infectious Diseases and Internal Medicine Centre Hospitalier Universitaire de LiegeLiege 4000Belgium Department of Pathology Centre Hospitalier Universitaire de LiegeLiege 4000Belgium Department of Gastroenterology and Hepatology Centre Hospitalier Universitaire de LiegeLiege 4000Belgium

Chronic hepatitis C virus(HCV) infection is associated with multifarious extra-hepatic manifestations;the most described and discussed being mixed cryoglob-ulinemia which is strongly related to B-cell lympho-proliferative disorders(LPDs).We present a case of chronic HCV infection and mixed cryoglobulinemia,with minimal liver *** case is a 53-year-old patient who was diagnosed as having bone marrow hypoplasia at the age of *** received several blood transfusions to normalize her *** the age of 31,she was diagnosed with rheumatoid ar-thritis on account of her diffuse joint pain and inflam-mation,elevated rheumatoid factor(Rf) and Raynaud's *** years later,monoclonal gam-mopathy of IgG Lambda(one year later,changed to IgM Kappa) was detected during a routine examina-tion.A bone marrow biopsy showed hypoplasia,Kappa positive B-lymphocytes and low-grade malignant lym-phoma *** of the bone marrow aspirate was not *** treatment was initiated owing to herpoor bone marrow function and she is under regular follow-up.

关键词： Chronic hepatitis C infection Mixed cryoglobulinemia Prognosis

Granular materials: Bridging damaged solids and turbulent fluids

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Theoretical & Applied Mechanics Letters 2013年第2期3卷 41-45页

作者： Q. sun s. song j. Liu M. fei f. jin state Key Laboratory of Hydroscience & Engineering Tsinghua University

Granular materials exhibit abundant dissipations due to fluctuations in both granular motions and configurations （i.e., granular skeleton） evolutions. Twin granular temperatures Tk and T~ are introduced accounting for two types of fluctuations, and the so-called twin granular temperatures theory is established as an extension of granular solid hydrodynamics. By using simulations, the nonaffine deformations in a 2D assembly are simulated by using discrete element methods. By analogizing with microdamages in deformed solids, double scalar damage variables, Dp and Dq, are proposed to describe the deformed granular solid under triaxial compressions. Granular flows are found intrinsically turbulent due to the presence of Tk and the Naiver stokes equation is obtained for granular flows.

关键词： non-equilibrium thermodynamics granular temperature damage mechanics turbulentflow

慢性静脉功能不全对初次全膝关节置换术的影响:一项120万例分析

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临床骨科杂志 2024年第1期27卷 121-121页

作者： sUMMERs s YAKKANTI R OCKsRIDER j 胡孔足(摘译) 不详

慢性静脉功能不全在老年人群非常多见,美国大约有超过300万例。作者利用管理部门数据库分析了1265534例初次行全膝关节置换术患者的资料,其中210926例合并慢性静脉功能不全,1054608例无慢性静脉功能不全者作为对照。结果发现,合并慢性... 详细信息

慢性静脉功能不全在老年人群非常多见,美国大约有超过300万例。作者利用管理部门数据库分析了1265534例初次行全膝关节置换术患者的资料,其中210926例合并慢性静脉功能不全,1054608例无慢性静脉功能不全者作为对照。结果发现,合并慢性静脉功能不全的患者住院时间更长,90 d内再入院率更高,内科并发症发生率更高,假体周围感染率更高,感染以外的假体相关并发症发生率也更高,90 d内治疗费用更多($15583.07vs$14286.95)。

关键词：并发症发生率慢性静脉功能不全假体周围感染再入院率全膝关节置换术老年人群数据库分析治疗费用

Ultrastructural Alterations in Testes from Rats Treated with Cysteine

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Biomedical and Environmental sciences 1993年第2期6卷 172-178页

作者： A.s.BERNACCHI E.C.DEfERREYRA C.R.DECAsTRO j.A.CAsTRO Centro CentroCentroCentro de Investigaciones Toxicologicas(CEITOX)CITEFA/CONICETZufriategui4380(1603)Villa MartelliPcia.de Buenos AiresArgentina

Cysteinc administration in relatively large doses has been repetitively employed as preventive agent against chemically induced cell injury or as *** this work we report that administration of a dose standard for those purposes(1.9gr/kg,po in water)causes significant ultrastructurally evident alterations in testcs at *** involves scrtoli cells and *** found in the former include dilatation of nuclear membrane and of the smooth(sER)and rough endoplasmic reliculum(RER)and detachment of ribosomes from *** appeared more sparse and electron lucent than in controls and contained more lipid droplets and *** exhibited alterations in shape and *** in spermatids consisted of the appearance of irregular shape of the nucleus and alterations in their acrosomal *** was no histochemical evidence for either calcium accumulation or lipid peroxidation occurrence in testes of cysteine-trcated *** indicate that the large doses of cysteine employed in prevention of radiation or chemical effects is able to cause injury to sertoli cells of the *** observed does not reach irreversible stages but may be sufficient to lead to production of abnormal spermatids.

关键词：抗辐射药半胱氨酸处理大鼠睾丸组织生精能力超微结构变化

Transoral surgery for morbid obesity

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World journal of Gastrointestinal Endoscopy 2011年第11期3卷 201-208页

作者： sabrena f Noria Dean j Mikami Department of surgery Division of General and Gastrointestinal SurgeryCenter for Minimally Invasive SurgeryThe Ohio State UniversityColombusOH 43210United States Department of surgery Division of General SurgeryTulane University School of MedicineNew OrleansLA 70112-2699United States

Obesity is a serious health problem in the United *** laparoscopic surgical procedures are effective in achieving weight loss and improving obesity-related co-morbidities,they are not without their limitations and consequently there is a growing demand for less invasive *** techniques,as both primary and revisional procedures,are promising in this regard as they may provide a safer and more cost-effective means of achieving meaningful weight *** aim of this paper is to review the currently available transoral approaches to weight loss,with a particular focus on those applied in human trials.

关键词： Obesity Transoral techniques Humans

Low-cycle fatigue Behaviors of an As-extruded Mg-12%Gd-3%Y-0.5%Zr Alloy

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journal of Materials science & Technology 2013年第8期29卷 775-780页

作者： s.M.Yin s.X.Li shenyang University of Chemical Technology shenyang National Laboratory for Materials science Institute of Metal ResearchChinese Academy of Sciences

Cyclic deformation and fatigue behaviors of Mg-12%Gd-3%Y-0.5%Zr （wt%, GW123K） alloy were investigated at room temperature under axial cyclic loading in strain controlled condition. It is shown that conventional extruded GW123K alloy maintained cyclic stability at strain amplitudes ranging from 2 × 10^-3 to 10^-2. The pronounced symmetric hysteresis loops were also observed during cyclic loading. fracture surface observations indicated that fatigue cracks mainly initiated at large Gd-riched phase or at inclusion clusters at surface or subsurface, and grain boundary （GB） and slip bands （sBs） are also preferential sites for micro-crack incubation.

关键词： Magnesium alloy Low-cycle fatigue Cyclic stabilization fatigue crack fractography