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Principles to Support Modular Software Construction

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Journal of Computer Science & Technology 2017年第1期32卷 3-10页

作者： Jack b. Dennis Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

The construction of large software systems is always achieved through assembly of independently written components -- program modules. For these software components to work together, they must share a common set of data types and principles for representing structured data such as arrays of values and files. This common set of tools for creating and operating on data objects is provided by the infrastructure of the computer system： the hardware, operating system and runtime code. because the nature and properties of these tools are crucial for correct operation of software components and their inter-operation, it is essential to have a precise specification that may be used for verifying correctness of application software on one hand, and to verify correctness of system behavior on the other. We call such a specification a program execution model （PXM）. It is evident that the properties of the PXM implemented by a computer system can have serious impact on the ability of application programmers to practice modular software construction. This paper discusses the concept of program execution models and presents a set of principles that a PXM must satisfy to provide a sound basis for modular software construction. because parallel program execution on computer systems with many processing units is an essential part of contemporary computing environments, the expression of parallelism and modular software construction using components involving parallel operations is included in this treatment. The conclusion is that it is possible to build computer systems that implement a PXM within which any parallel program may be used, unmodified, as a component for building more substantial parallel programs.

关键词： program execution model data flow model codelet abstract architecture parallel computing

经皮冠状动脉介入治疗64例静脉桥血管病变的临床疗效

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中华心血管病杂志 2005年第3期33卷 221-223页

作者：李志忠 sidney L Juergens CP 朱小玲陶英刘彤王苏李勇北京安贞医院心肺血管病医疗抢救中心 100029 澳大利亚Liverpool医院心内科

目的　评价静脉桥血管经皮冠状动脉介入治疗及支架治疗后的早期临床结果。方法对 64例 91处大隐静脉桥血管病变行介入治疗,将术中及住院期间的临床结果和术中应用的其他介入治疗辅助装置一并录入数据库并进行分析。结果　手术成功率 95.... 详细信息

目的　评价静脉桥血管经皮冠状动脉介入治疗及支架治疗后的早期临床结果。方法对 64例 91处大隐静脉桥血管病变行介入治疗,将术中及住院期间的临床结果和术中应用的其他介入治疗辅助装置一并录入数据库并进行分析。结果　手术成功率 95. 3%;术中发生非Q波心肌梗死1例(1. 6% )。一过性无再流现象 4例(6. 3% ),其中 1例置入支架后无再流而出现室颤,经电除颤、心脏按压、气管插管及置入主动脉内气囊反搏装置后血流恢复正常。应用血管远端保护装置 7例(10. 9% ),X sizer取栓系统 4例;术中或术后应用血小板GPⅡb/Ⅲa受体拮抗剂 25例 (39. 1% )。住院期共发生非Q波心肌梗死 2例,主要心脏不良事件发生率为 3. 1%。结论　静脉桥血管的经皮冠状动脉介入加支架治疗的即刻成功率高,近期临床效果满意,中、远期结果有待进一步随访;血管远端保护装置和血小板受体拮抗剂的应用有可能改善预后。

关键词：静脉血管病变经皮冠状动脉介入治疗非Q波心肌梗死支架治疗术中临床疗效远期恢复成功率

Challenge of global climate change:Prospects for a new energy paradigm

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Frontiers of Environmental Science & Engineering 2010年第1期4卷 2-11页

作者： Michael b.MCELROY School of Engineering and Applied Sciences and Department of Earth and Planetary Sciences Harvard UniversityCambridgeMA 02138USA

Perspectives on the challenge posed by potential future climate change are presented including a discussion of prospects for carbon capture followed either by sequestration or reuse including opportunities for alternatives to the use of oil in the transportation *** potential for wind energy as an alternative to fossil fuel energy as a source of electricity is outlined including the related opportunities for cost effective curtailment of future growth in emissions of CO_(2).

关键词： climate change carbon capture wind ethanol CO_(2) radiative forcing

WEIERSTRASS POLYNOMIALS AND PLANE PSEUDO-HOLOMORPHIC CURVES

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Chinese Annals of Mathematics,Series b 2002年第1期23卷 1-10页

作者： b.SIEbERT TIANGANG FakultaetfürMathematik Ruhr-UniversitaetBochumD-44780BochumGermany DepartmentofMathematics MITCambridgeMA02139-4307U.S.A InstituteofMathematics PekingUniversityBeijing100871

For an almost complex structure J on U R4 pseudo-holomorphically fibered over C a J-holomorphic curve C U can be described by a Weierstrass polynomial. The J-holomorphicity equation descends to a perturbed 8-operator on the coefficients; the operator is typically (0, 2/m)-Holder continuous if m is the local degree of C over C. This sheds some light on the problem of parametrizing pseudo-holomorphic deformations of J-holomorphic curve singu-larities.

关键词： Weierstrass polynomials Plane pseudo-holomorphic curves

Pleistocene glaciation advances the cryptic speciation of Stellera chamaejasme *** a major biodiversity hotspot

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Journal of Integrative Plant biology 2024年第6期66卷 1192-1205页

作者： Santosh Kumar Rana Hum Kala Rana Jacob bLandis Tianhui Kuang Juntong Chen Hengchang Wang Tao Deng Charles C.Davis Hang Sun CAS Key Laboratory for Plant Diversity and biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Arkansas biosciences Institute Arkansas State UniversityJonesboroArkansas 72401USA School of Integrative Plant Science Section of Plant Biology and the L.H.Bailey HortoriumCornell UniversityIthacaNew York 14853USA bTI Computational biology Center Boyce Thompson InstituteIthacaNew York 14853USA CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Chinese Academy of SciencesWuhan Botanical GardenWuhan 430074China Department of Organismic and Evolutionary biology HerbariaHarvard UniversityCambridgeMassachusetts 02138USA

The mountains of Southwest China comprise a significant large mountain range and biodiversity hotspot imperiled by global climate *** high species diversity in this mountain system has long been attributed to a complex set of factors,and recent large-scale macroevolutionary investigations have placed a broad timeline on plant diversification that stretches from 10 million years ago(Mya)to the *** our increasing understanding of the temporal mode of speciation,finer-scale populationlevel investigations are lacking to better refine these temporal trends and illuminate the abiotic and biotic influences of cryptic *** is largely due to the dearth of organismal sampling among closely related species and populations,spanning the incredible size and topological heterogeneity of this *** study dives into these evolutionary dynamics of speciation using genomic and ecomorphological data of Stellera chamaejasme *** identified four previously unrecognized cryptic species having indistinct morphological traits and large metapopulation of evolving lineages,suggesting a more recent diversification(~2.67-0.90 Mya),largely influenced by Pleistocene glaciation and biotic *** factors likely influenced allopatric speciation and advocated cyclical warming–cooling episodes along elevational gradients during the *** study refines the evolutionary timeline to be much younger than previously implicated and raises the concern that projected future warming may influence the alpine species diversity,necessitating increased conservation efforts.

关键词： cryptic speciation glacial-interglacial Hengduan Mountains north-south migration Stellera chamaejasme

Toxicity and Carcinogenicity of Ozone in Combination with 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone and Dibutyl Phthalate in b6C3F1 Mice for 16 and 32 Weeks

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biomedical and Environmental Sciences 2009年第3期22卷 216-222页

作者： MIN YOUNG KIM M YUNG CHO Laboratory of Toxicology College of Veterinary MedicineSeoul National University biological Engineering Department Massachusetts Institute of Technology

Objective To evaluate the toxic and carcinogenic potential of ozone alone or in combination with 4-（N-methyl-N-nitrosamino）-1-（3-pyridyl）-1-butanone （NNK） and/or dibutyl phthalate （DbP）. Methods Male and female b6C3F1 mice were exposed, through inhalation, intravenous administration and diet, to 0.5 ppm of ozone, 1.0 mg/kg of NNK and 5000 ppm of DbP, individually and in combination for 16 and 32 weeks. Results No treatment-related death was seen, but significant differences in body and organ weights between control and treated mice were observed during the study. No incidence of lung tumor incidence was recorded in mice exposed to either ozone alone or combined treatment. Oviductal carcinomas were observed in female mice exposed to ozone or DbP alone for 16 weeks and ozone in combination with NNK and DbP for 32 weeks. Conclusion Although ozone alone and in conjunction with NNK and/or DbP does not induce lung cancer under our experimental conditions, they induce oviductal carcinomas in b6C3F1 mice.

关键词： Ozone NNK DbP Combined treatment Toxicity Carcinogenicity

STAbLE,FLUXIONAL AND LESS STAbLE SMALL bORANES——THEORETICAL STUDIES

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分子科学与化学研究 1982年第4期 9-14页

作者： WilliamN.Lipscomb Gibbs Chemical Laboratory Harvard University Cambrudge Massachusetts 02138 USA

ELECTTON correlation corrections are required in order to ac-count for the stability of bH5,the dissociation energy ofb2H6,and the selection of the most stable isomers of b3H7,b4H8,b4H10 and *** fluxional nature of b3... 详细信息

关键词： St STAbLE,FLUXIONAL AND LESS STAbLE SMALL bORANES THEORETICAL STUDIES

1989—1990年中天山的冰川径流状况研究(英文)

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冰川冻土 1993年第3期15卷 442-459页

作者： Vladimir b. Aizen Elena M. Aizen(Institute of Geography of the Russian Academy of Sciences, borisovskiy Pr. 36, Korp. 3, 115563 Moscow, RUSSIA)Victor N. Nesterov(Institute of Oceanography, Far East branch Russian Academy of Science, Kaplunova str.8, flat 175, Vladivostok 690013 RUSSIA )David D. Sexton(Scott Polar Research Institute, University of cambridge Lensfield Road, cambridge ENGLAND Cb2 IER.)

通过冰川学、气象学、日射、地球化学和同位素分析,以及野外观测和统计分析,认清了控制—内陆冰川作用大系统的各主要过程。野外工作包括不同天气类型和不同高度(积累区、粒雪界和消融区)的气象条件、各辐射和热量平衡分量、积累和消融... 详细信息

通过冰川学、气象学、日射、地球化学和同位素分析,以及野外观测和统计分析,认清了控制—内陆冰川作用大系统的各主要过程。野外工作包括不同天气类型和不同高度(积累区、粒雪界和消融区)的气象条件、各辐射和热量平衡分量、积累和消融。.划分了成冰带,提出系统内水转换的估算方法,可能对各水文要素作短期和长期预报。

关键词：冰川径流天山

消泡剂和溶粘液剂作为术前用药改善胃镜观察效果

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消泡剂和溶粘液剂作为术前用药改善胃镜观察效果

作者：杰克斯（Jecson sidney De Carvalho Sanches）东南大学

学位级别：硕士

背景:上消化道内镜检查是诊断和治疗上消化道疾病最常用的方法之一,为鉴别早期肿瘤病变提供了独特的机会。为了获得最佳高质量的上消化道内镜,良好的胃和粘膜的可视化非常重要。然而,泡沫、气泡和黏液常常阻碍其可见性,此外,还延长了手... 详细信息

背景:上消化道内镜检查是诊断和治疗上消化道疾病最常用的方法之一,为鉴别早期肿瘤病变提供了独特的机会。为了获得最佳高质量的上消化道内镜,良好的胃和粘膜的可视化非常重要。然而,泡沫、气泡和黏液常常阻碍其可见性,此外,还延长了手术的持续时间,影响了患者的耐受性和执行内镜医师的满意度。目前内镜医师在内镜检查中使用不同的术前药物,以减少泡沫、气泡和黏液的含量。目的:评价不同术前用药的疗效及它们在上内镜检查中增强粘膜可视性和安全性的联合作用方法:单中心、前瞻性、双盲（患者和医生）、随机研究。共有250名患者转诊至东南大学附属中大医院,在消化科门诊和住院接受选择性胃镜检查。参与者被随机分配接受五种药物中的一种:A组:西甲硅油,b组:西甲硅油加链霉蛋白酶,C组:二甲硅油,D组:二甲硅油加链霉蛋白酶,E组:链霉蛋白酶。在内窥镜检查前15到30分钟,患者接受了指定组的术前准备。在内镜检查中,对食管、胃体和胃窦的粘膜可见度进行评估,可见度评分分为1-3分。1=无气泡和轻微气泡（≤25%气泡）),无黏液,粘膜清晰可见;2=中等气泡（25%0%气泡）黏液薄层,但不遮挡视力;3=严重气泡（≥50%气泡）黏液遮挡视力。符合以下排除标准的患者被排除在外:急诊病例,以前接受过全胃切除术的患者,胃肠道出血,已知肿瘤或狭窄,对试验药物过敏,孕妇或哺乳期妇女。结果:将250例患者、122例男性患者和128例女性患者随机分为5组,每组50例。5组在年龄、性别和主要手术指征方面均无统计学意义。在食管部位,C组和D组总得分最高。而在胃体和胃窦部位,b组和D组有着更好的视觉效果。结论:为了获得上消化道的最佳视野,使其不存在过多的气泡和黏液,建议在上消化道内镜检查前使用消泡剂（西甲硅油或二甲硅油）和溶黏液剂（链霉蛋白酶）。

关键词：上消化道内镜西甲硅油二甲硅油链霉蛋白酶内镜术前用药