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计算机科学 1990年第6期17卷 1-4页

作者： owen,K 王献昌

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Rich as a King

语言教育 1998年第6期 35-36页

作者： David owen 张江云

William I,who conquered England some 930 years ago,had wealth,power and a ruthless *** although Williamwas stupefyingly rich by the standard of his time,he hadnothing remotely resembling a flush *** paper towels,no riding lawn *** did he get by?History books are filled with wealthy people who werepractically destitute compared to me.I have

关键词： Rich as a King

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Comparison of Geometric Partitioning Algorithms for Parallel Analysis of Finite-Discrete System

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Comparison of Geometric Partitioning Algorithms for Parallel...

The Sixth World Congress on Computational Mechanics in Conjunction with the Second Asian-Pacific Congress on Computational Mechanics

作者： D.R.J.owen Civil & Computational Engineering Centre University of Wales Swansea Swansea SA28PP U.K.

The efficient execution of parallel finite-discrete element analysis requires a mapping of the computational objects onto processors such that each processor get s roughly an equal amount of object weight and that the amount of interprocessor communication is minimi zed. Such a mapping is commonly found by partitioning the entire domain. This paper reviews the major classes of partitioning algorithms and discusses the suitability of three typical geometric partitioning algorithms (i.e. RCB, UCB and Octree) on finite -discrete element problems. The main inclusions are as follows: (1) Although topological algorithms can produce better partitions than geometric algorithms, but are more expensive. Geometric methods are more suited to finite -discrete element simulation than topological methods. (2) The quality of partitions generated by RCB is slightly poorer than those produced by UCB and Octree. However, its simplicity an d speed are appealing. Good load balance can be obtained by using a modified RCB algorithm proposed by the authors [1]. (3) Jones and Plassmann reported that URB algorithm leads to a modest reduction in communication cost [2]. However, this result was not observed in the current study. The fact is that the idle seconds for synchronization increase explicitly with the contact developing. Although the communication amount is kept small, but the time used for communication and synchronization is large. It tend s to work well when only no contact occurs. The overall communication performance of URM is much worse than those of RCB. (4) The partitions produced by Octree algorithm are not confined in simple boxes. Octree algorithm is fast and is easy to make data mi gration [3]. However, the long boundary size increases the buffer between two adjacent subdomains. Thus, it results more communications. The programming complicacy of Octree algorithm is larger than any of other methods. If we consider the overall performances of all partitioning algorithms, RCB

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充满机会朝气勃勃的温哥华

技术经济与管理研究 1997年第3期 23-24页

作者： MayorPhilipW.owen

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GOLF JUNK

世界高尔夫 2010年第10期 91-98页

作者： DAN owen barry m 孔祥盈

本月我们为您带来改头换面的Never Compromise推杆、TaylorMade的发球木杆还有日本最热的挖起杆。Never CompromiseNCX-RAY推杆1.29英镑经过几个赛季的冬眠期后,Never Compromise重新回归,产品的种类和颜色更加多样。NCX推杆最大的特点... 详细信息

本月我们为您带来改头换面的Never Compromise推杆、TaylorMade的发球木杆还有日本最热的挖起杆。Never CompromiseNCX-RAY推杆1.29英镑经过几个赛季的冬眠期后,Never Compromise重新回归,产品的种类和颜色更加多样。NCX推杆最大的特点是采用了全新的嵌入物,SFT(Suspended FaceTechnology)技术使打出的球呈现前回旋且滚动平稳。

关键词：推杆击球重心英镑球杆平衡设计击打颜色实现木杆

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A Robust Contact Model for Rigid Super-Quadrics

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A Robust Contact Model for Rigid Super-Quadrics

A Rare Case of Anterior Sacral Meningocele (ASM) in a Young Patient

The Sixth World Congress on Computational Mechanics in Conjunction with the Second Asian-Pacific Congress on Computational Mechanics

作者： D.R.J.owen Civil & Computational Engineering Centre University of Wales Swansea SA2 8PP UK

Disks and spheres are the most commonly used geometric objects in discrete element simulations, mainly due to their geometric simplicity and highly computational efficiency. However, a drawback of disk/spherical elements is that they completely lack angularity, i.e. cannot provide any resistance to rolling motion. It has been increasingly recognised that the angularity of arbitrary shaped objects generally plays a fundamental role in the dynamic behaviour of many practical problems. Consequently a number of non-circular/spherical discrete elements have been used among which super-quadrics [1] are the most general. A 3D super-quadric is defined by the following implicit function:where parameters a, b, c and m determine the shape of the super-quadric. Note that disk/sphere and ellipse/ellipsoid are all special cases of super-quadrics. Despite its mathematic elegancy and smooth boundary, super-quadrics are not widely used because of a high computational cost associated with its contact detection. An overlap check between two super-quadrics may involve numerically obtaining the intersections of two nonlinear functions, which is a very expensive operation and may fail in certain circumstances. In order to overcome these difficulties, Williams & Pentland [2] proposed a more efficient discretised version but with a degraded accuracy. The present work follows a similar idea. The main steps of the proposed algorithm include: 1) an adaptive sampling procedure is employed to represent a super-quadric by a polygon;2) based on the overlap zone of the bounding boxes of the two super-quadrics, the two polygons are clipped to exclude those edges lying outside the overlap zone;3) an effective polygon intersection algorithm is adopted to find the intersections and overlap area of the two clipped polygons, if they exist;and 4) a robust polygon/polygon contact model [3] is then applied to determine the contact forces between the two objects. The algorithm can be applied to any super-qu

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Open Journal of Modern Neurosurgery 2016年第1期6卷 16-19页

作者： Shanu Gambhir Mark Winder Gareth owen Department of Neurosurgery St. Vincent’s Hospital Darlinghurst Australia

We report a 24-year-old male who presented with abdominal distension, constipation and left sided groin pain. CT and MRI of the abdomen/spine were performed which showed a large anterior sacral meningocele occupying most of the pelvic and abdominal cavity and displacement of their respective contents. Initially a posterior approach with lumbosacral laminectomy (L5 - S4) was performed. The ostium of the meningocele was identified with several nerve roots identified passing through, adjacent and into the defect. As nerve roots traversed the ostium, watertight closure was not feasible without sacrificing nerve roots. Subsequent MRI demonstrated recurrence of approximately 60% of the anterior sacral meningocele. We therefore opted to approach the ASM anteriorly via an anterior approach with the help of colorectal surgical colleague. The ASM was completely embedded within the sigmoid and upper to mid rectal mesentry, with its own vascular supply to the thick walled capsule. This case highlights the need for a combined approach due to the incorporation of the pseudomeningocele into the omentum with the development of its own blood supply.

关键词： Spina Bifida Sacral Meningocele Abdominal Distension

Commercial Whaling Ban Holds-for Now

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当代外语研究 2005年第8期 10-11页

作者： James owen 李海龙

由于人们对自然资源的过度采伐,许多物种都几近灭绝。地球上最大的哺乳动物鲸鱼的数量日益减少,为此,国际捕鲸委员会曾禁止商业性捕捞鲸鱼的活动。有些国家为了本国私利企图恢复商业捕捞,这理所当然地遭到环保人士的普遍反对。这显示了... 详细信息

由于人们对自然资源的过度采伐,许多物种都几近灭绝。地球上最大的哺乳动物鲸鱼的数量日益减少,为此,国际捕鲸委员会曾禁止商业性捕捞鲸鱼的活动。有些国家为了本国私利企图恢复商业捕捞,这理所当然地遭到环保人士的普遍反对。这显示了关于人与自然关系不同观点间的又一次较量。

关键词：哺乳动物自然资源不同观点人与自然关系商业性鲸鱼捕捞委员会灭绝采伐

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外周血foxp3基因特异性甲基化区域甲基化水平检测：可作为自身免疫病与慢性感染患者病情评估潜在的标记物

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外周血foxp3基因特异性甲基化区域甲基化水平检测：可作为自身免...

作者： owen Ngalamika（欧文）中南大学

学位级别：硕士

背景：自身免疫疾病是指机体对自身抗原发生免疫反应而导致自身组织损害所引起的疾病。系统性红斑狼疮和银屑病均为自身免疫性疾病,前者可累及全身多系统,而后者主要累及皮肤。慢性皮肤感染主要为细菌、病毒、真菌感染引起的以皮肤黏膜... 详细信息

背景：自身免疫疾病是指机体对自身抗原发生免疫反应而导致自身组织损害所引起的疾病。系统性红斑狼疮和银屑病均为自身免疫性疾病,前者可累及全身多系统,而后者主要累及皮肤。慢性皮肤感染主要为细菌、病毒、真菌感染引起的以皮肤黏膜病变为主的一类疾病。调节性T细胞(regulatory T cells, Tregs)是能够抑制免疫反应的细胞群,在免疫病理、移植物耐受、阻止自身免疫反应和维持机体免疫平衡方面发挥重要的作用。调节性T细胞功能失调与人类多种重大疾病,如自身免疫性疾病、感染性疾病、过敏性疾病、恶性肿瘤、移植排斥的发生、发展及治疗都密切相关。FOXP3是叉状头转录因子家族中的一个成员,它是调节性T细胞(Treg)的标志性分子。FOXP3基因突变能引起严重的自身免疫性疾病,因此Foxp3在调节机体免疫自稳中起关键作用。FOXP3作为一个转录调控因子,通过直接调控多种基因来调节Treg的活性。表观遗传学是研究基因的核苷酸序列不发生改变的情况下,基因表达了可遗传的变化的一门遗传学分支学科。表观遗传的现象很多,已知的有DNA甲基化(DNA methylation),基因组印记(genomic impriting),母体效应(maternal effects),基因沉默(gene silencing),核仁显性,休眠转座子激活和RNA编辑(RNA editing)等。FOXP3基因中TSDR是一段高度保守的富含CpG位点的区域,在自然Treg中这段区域是完全去甲基化,但非Treg T细胞中则是完全甲基化的。高分辨率熔解(High-resolution melting,简称HRM)分析是一门新兴的技术。它仅仅通过PCR之后的熔解曲线分析,就能检测PCR片段的微小序列差异,从而应用在突变扫描、序列配对和基因分型等多个万面。凭借其速度和简便性，高分辨率熔解这种方法正在迅速普及。目前国内外尚无关于采用高分辨率溶解曲线分析技术检测上述疾病foxp3基因TSDR区域甲基化状态的相关资料。目的：此研究采用高分辨率溶解曲线分析技术检测自身免疫病与慢性感染患者foxp3基因TSDR区域甲基化状态,以探讨FOXP3基因TSDR区域甲基化对天然调节性T细胞的影响,同时观察FOXP3基因TSDR甲基化水平与系统性红斑狼疮疾病活动性的相关性。方法：从65例系统性红斑狼疮(包括狼疮活动期与非活动期患者)、30例银屑病、30例慢性皮肤感染(痤疮、甲真菌病、生殖器疱疹和单纯疱疹)患者以及23例健康人中抽取静脉血200ul,提取基因组DNA,重亚硫酸盐处理未发生甲基化的胞嘧啶,然后在rotor gene-6000仪器上进行高分辨率溶解曲线-PCR以检测溶解温度。结果：与其它各组比较,活动期SLE患者溶解温度最高(溶解温度越高代表甲基化水平越高,反之亦然),且有统计学意义(79.00±0.28vs其它组,p<0.001).与非活动性SLE组比较,银屑病组溶解温度较高,且有统计学意义(78.62+0.20vs78.49±0.29,p<0.05);与健康组比较,银屑病组溶解温度较高,且有统计学意义(78.62±0.20vs78.44±0.25,p<0.01)。非活动性SLE与健康人比较,溶解温度无明显统计学意义(78.49±0.29vs78.44±0.25,p=0.464)。SLE活动性与溶解温度呈明显正相关。另外,慢性感染组与健康组比较,溶解温度更低,具有统计学差异(78.28±0.21vs78.44±0.25,p<0.05)。讨论：Foxp3是Treg发育过程中的主要调控者,其表达直接影响体内Treg水平。因此,Foxp3的高表达与体内Treg的高水平相关,反之亦然。Foxp3基因中TSDR是一段高度保守的富含CpG位点的区域,在自然Treg中这段区域是完全去甲基化,但非Treg T细胞中则是完全甲基化的。TSDR的去甲基化与foxp3的稳定表达相关,而TSDR的甲基化则可以降低foxp3的转录活性。现已证实通过PCR及其他DNA甲基化分析方法来检测foxp3中TSDR甲基化状态是一种能监测和定量外周血及组织中Treg含量的可靠方法。Foxp3中TSDR处于非甲基化状态时,能够通过结合转录因子如CREB和ATF,进而促进启动子活性。另外,通过比较Treg及非Treg T细胞中foxp3TSDR组蛋白H3、H4乙酰化水平发现组蛋白H3、H4乙酰化使foxp3稳定表达。在此研究中,我们通过运用HRM-PCR法,以自身免疫性疾病患者及慢性皮肤微生物感染患者为研究对象,分析其外周血分离的全基因组DNA中foxp3TSDR甲基化水平。研究结果发现,活动性SLE患者及银屑病患者的foxp3TSDR甲基化水平明显高于正常对

关键词：自身免疫病慢性感染 FOXP3基因TSDR区域调节性T细胞高分辨率溶解曲线-PCR

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三维纹理与贴图创作艺术