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The dynamical complexity of work-hardening:a large-scale molecular dynamics simulation

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Acta Mechanica Sinica 2005年第2期21卷 103-111页

作者： MarkusJ.Buehler AlexanderHartmaier marka.Duchaineau FaridEAbraham HuajianGao MaxPlanckInstituteforMetalsResearch Heisenbergstrasse3D-70569StuttgartGermany CaliforniaInstituteofTechnology 1201EastCaliforniaBlvd.Pasadena91125CAUSA//MaxPlanckInstituteforMetalsResearchHeisenbergstrasse3D-70569StuttgartGermany LawrenceLivermoreNationalLaboratory 7000EastAve.LivermoreCA94550USA IBMAlmadenResearchCenter 650HarryRoadSanJoseCA95120USA

We analyze a large-scale molecular dynamics simulation of work hardening in a model system of a ductile solid. With tensile loading, we observe emission of thousands of dislocations from two sharp cracks. The dislocations interact in a complex way, revealing three fundamental mechanisms of work-hardening in this ductile material. These are (1) dislocation cutting processes, jog formation and generation of trails of point defects; (2) activation of secondary slip systems by Frank-Read and cross-slip mechanisms; and (3) formation of sessile dislocations such as Lomer-Cottrell locks. We report the discovery of a new class of point defects referred to as trail of partial point defects, which could play an important role in situations when partial dislocations dominate plasticity. Another important result of the present work is the rediscovery of the Fleischer-mechanism of cross-slip of partial dislocations that was theoretically proposed more than 50 years ago, and is now, for the first time, confirmed by atomistic simulation. On the typical time scale of molecular dynamics simulations, the dislocations self-organize into a complex sessile defect topology. Our analysis illustrates numerous mechanisms formerly only conjectured in textbooks and observed indirectly in experiments. It is the first time that such a rich set of fundamental phenomena have been revealed in a single computer simulation, and its dynamical evolution has been studied. The present study exemplifies the simulation and analysis of the complex nonlinear dynamics of a many-particle system during failure using ultra-large scale computing.

关键词： Work-hardening Large-scale atomistic simulation Dislocation junction Cross-slip

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部分剪切连接的组合梁强度和延性性能

华南理工大学学报（自然科学版） 2000年第12期28卷 143-148页

作者：季静 marka.13 华南理工大学建筑学院广东广州510640

对部分剪切连接的钢－混凝土组合梁的截面特性进行了全过程分析，同时将计算机分析结果与简单的刚塑性手算方法进行比较，并对部分剪切连接的组合梁的强度和延性进行了探讨。

关键词：组合梁部分剪切连接计算机分析强度延性钢-混凝土组合结构

Preparing for OSHA's voluntary protection programs a guide to success Brian T. Bennett, Norman R. deitch.

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2010年

作者： Brian T. Bennett Norman R. deitch.

来源：畅想之星图书光盘版（南... 评论

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多器官衰竭

国外医学（创伤与外科基本问题分册） 1993年第3期14卷 135-137页

作者： deitch EA 孙珍

本文主要阐述了多器官衰竭(MOF)的发病原因和发病机理,特别是MOF的几个假说,以及MOF的治疗方法和假说推动的可能的治疗方法。

关键词：多器官衰竭病理

Inhibitory effect of tumor suppressor p33^(ING1b) and its synergy with p53 gene in hepatocellular carcinoma

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World Journal of Gastroenterology 2005年第13期11卷 1903-1909页

作者： ZhiZhu JingLin Jian-HuiQu marka.Feitelson Can-RongNi Fang-MeiLi Ming-HuaZhu DepartmentofPathology ChanghaiHospitalSecondMilitaryMedicalUniversityShanghai200433China DepartmentofPathology AnatomyandCellBiologyThomasJeffersonUniversityPhiladelphiaPAUSA

AIM: To investigate the inhibitory effect of tumor suppressor p33ING1b and its synergy with p53 gene in hepatocellular carcinoma (HCC).METHODS: Recombinant sense and antisense p33ING1b plasmids were transfected into hepatoma cell line HepG2 with lipofectamine. Apoptosis, G0/G1 arrest, cell growth rate and cloning efficiency in soft agar of HepG2 were analyzed after transfection. In three hepatoma cell lineswith different endogenous p53 gene expressions, the synergistic effect of p33ING1b with p53 was analyzed by flow cytometry and luciferase assay was performed to detect the activation of p53 downstream gene p21WAF1/CIP1. In addition, the expression and mutation rates of p33ING1b in HCC tissues were measured by immunohistochemistry and polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP).RESULTS: Overexpression of p33ING1b inhibited cell growth of HepG2, induced more apoptosis and protected cells from growth in soft agar. Combined transfer of p33ING1b and p53 gene promoted hepatoma cell apoptosis, G0/G1 arrest and elevated expression of p21WAF1/CIP1. Immunostaining results showed co-localized P33ING1b with P53 protein in HCC tissues and there was a significant relation between protein expression rates of these two genes (P＜0.01).Among 28 HCC samples, p33ING1b presented a low gene mutation rate (7.1%).CONCLUSION: p33ING1b collaborates with p53 in cell growth inhibition, cell cycle arrest and apoptosis in HCC. Loss or inactivation of p33ING1b normal function may be an important mechanism for the development of HCC retaining wildtype p53.

关键词： Gene p33INGlb Gene p53 Apoptosis Cell cycle arrest Gene p21wafl Liver neoplasm

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烧伤的处理

国外医学（创伤与外科基本问题分册） 1991年第4期12卷 205-206页

作者： deitch EA 唐晓熹

作者回顾了1985年以来烧伤处理的进展,提出对一些处理原则的总的看法,特别是对基础研究和临床治疗中有异议的一些领域,如休克复苏、代谢与营养、感染与免疫、创面处理等进行了评论。

关键词：烧伤心肺复苏感染代谢

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肠源性感染的实验研究

第三军医大学学报 1990年第1期12卷 1-69页

作者：马利黎鳌肖光夏 Edwin A deitch 西南医院烧伤研究所美国路易斯安娜州Shreveport医学院外科

感染仍然是外科危重病人的主要死因之一。30％以上死于感染和多脏器功能衰竭病人的感染病灶,即使在尸检时也从未明确。多数感染都是由G^-杆菌、肠球菌以及白色念株菌这一类肠道常驻菌群所致。设想肠道可以是全身感染的感染源。细菌经由... 详细信息

感染仍然是外科危重病人的主要死因之一。30％以上死于感染和多脏器功能衰竭病人的感染病灶,即使在尸检时也从未明确。多数感染都是由G^-杆菌、肠球菌以及白色念株菌这一类肠道常驻菌群所致。设想肠道可以是全身感染的感染源。细菌经由肠道通过肠粘膜侵入肠系膜淋巴结及体内其他脏器中的过程,国外称之谓“细菌的移居”,我们长期以来称之为“肠源性感染”。在外科临床上,休克、营养不良、内毒素血症及以肠道内容物郁滞为特征的肠麻痹等因素常常合并存在,这些因素对于临床的感染率和病死率有促进作用。为澄清它们与肠源性感染之间的关系,本实验选用950只无特殊致病动物及无菌动物,以细菌学研究为主,病理学观察为辅,结合生化和药理学方法;利用烧伤、出血性休克、内毒素血症、蛋白质营养不良及小肠梗阻等不同动物模型;从多个方面,不同层次,对创伤后早期阶段肠源性感染的发生、发展等方面进行了系统的研究。结果发现:烧伤后早期肠道内细菌可以侵入体内;一定时限的低血容量性休克能够造成肠源性感染;循环中的内毒素可以促进肠道中细菌的侵入;蛋白质营养不良对内毒素上述的致病作用具有协同作用以及单纯小肠梗阻后肠道内细菌可进行性地侵入体内;最终导致致死性的肠源性感染。实验证明,创伤后早期阶段。

关键词：肠源性感染烧伤出血性休克内毒素血症蛋白质营养不良肠梗阻

Endogenous fungal endophthalmitis:risk factors,clinical course,and visual outcome in 13 patients

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International Journal of Ophthalmology(English edition) 2021年第1期14卷 97-105页

作者： Jamel Corredores Itzhak Hemo Tareq Jaouni Zohar Habot-Wilner Michal Kramer Shiri Shulman Haneen Jabaly-Habib Ala'a Al-Talbishi Michael Halpert Edward Averbukh Jaime Levy Iris deitch-Harel Radgonde Amer Department of Ophthalmology Hadassah Medical CenterJerusalem 91240Israel Sackler Faculty of Medicine Tel Aviv UniversityTel Avi 6997801Israel Division of Ophthalmology Tel Aviv Sourasky Medical CenterTel Aviv 64239Israel Division of Ophthalmology Rabin Medical CenterPetah Tikva 49100Israel Department of Ophthalmology Poriya Medical CenterTiberias 1528001Israel St John Eye Hospital Jerusalem 91198Israel Faculty of Medicine Hebrew University of JerusalemJerusalem 9112102Israel

AIM:To analyze the risk factors,ophthalmological features,treatment modalities and their effect on the visual outcome in patients with endogenous fungal endophthalmitis(EFE).METHODS:Data retrieved from the medical files included age at presentation to the uveitis clinic,gender,ocular symptoms and their duration before presentation,history of fever,eye affected,anatomical diagnosis and laboratory evidence of fungal *** therapy recorded included systemic antifungal therapy and its duration,use of intravitreal antifungal agents and use of oral/intravitreal *** procedures and the data of ophthalmologic examination at presentation and at last follow-up were also ***:Included were 13 patients(20 eyes,mean age 58 y).Ten patients presented after gastrointestinal or urological interventions and two presented after organ *** one patient,there was no history of previous *** vitrectomy was performed in 16 eyes(80%)and vitreous cultures were positive in 10 of the vitrectomized eyes(62.5%).In only 4 patients(31%),blood cultures were *** patients received systemic antifungal *** eyes(80%)received intravitreal antifungal agent with voriconazole being the most commonly *** acuity(VA)improved from 0.9±0.9 at initial exam to 0.5±0.8 logMAR at last followup(P=0.03).A trend of greater visual improvement was noted in favor of eyes treated with oral steroids(±intravitreal dexamethasone)than eyes that were not treated with *** most common complication was *** eyes(60%)showed no ocular ***:High index of suspicion in patients with inciting risk factors is essential because of the low yield of blood cultures and the good general condition of patients at *** prognosis is improved with the prompt institution of systemic and intravitreal pharmacotherapy and the immediate surgical ***±local steroids could be considered

关键词： endophthalmitis endogenous fungal endophthalmitis endogenous endophthalmitis fungal endophthalmitis candida endophthalmitis

印楝素、印楝和苦楝种子抽提物在盆栽植物中的内吸作用(英文)

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Insect Science 1998年第2期5卷 177-188页

作者：胡美英,J．A．Klocke,marka．Barnby,赵善欢华南农业大学昆虫毒理研究室!广州 510642 ISKMountainViewResearchCenter!Inc.CA94087 USA ISKMountainViewResearchCenter!Inc.CA94087 USA 华南农业大学昆虫毒理研究室!广州 510642

本文报道具有拒食活性和生长发育调节作用的植物性杀虫剂印楝素、印楝和苦楝种子抽提物的内吸防治几种农业害虫的试验研究。结果表明：内吸施用印楝素或印楝种子粗提物（1mg和2．5mg／盆）能明显降低烟草天蛾幼虫的正常生长和干扰马铃... 详细信息

本文报道具有拒食活性和生长发育调节作用的植物性杀虫剂印楝素、印楝和苦楝种子抽提物的内吸防治几种农业害虫的试验研究。结果表明：内吸施用印楝素或印楝种子粗提物（1mg和2．5mg／盆）能明显降低烟草天蛾幼虫的正常生长和干扰马铃薯甲虫的生长发育；用≥25mg／盆的印楝素和印楝种子租提物能明显控制麦二叉蚜的种群繁殖。而苦楝种子甲醇抽提物对上述三种害虫的内吸控制种群繁殖作用不明显。

关键词： systemic action azadirachtin Azadirachta indica Melia azedarach