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Prevalence of metabolic syndrome in type 2 diabetic patients: A comparative study using WHO, NCEP ATP III, IDF and Harmonized definitions
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作者 Mun Chieng Tan Ooi Chuan Ng +3 位作者 Teck Wee Wong Anthony Joseph Yoke Mun Chan Abdul Rahman Hejar 《Health》 2013年第10期1689-1696,共8页
To determine the prevalence of metabolic syndrome (MetS) in Malaysian type 2 diabetic patients using WHO, NCEP ATP III, IDF and the new Harmonized definitions, and the concordance between these definitions. This study... To determine the prevalence of metabolic syndrome (MetS) in Malaysian type 2 diabetic patients using WHO, NCEP ATP III, IDF and the new Harmonized definitions, and the concordance between these definitions. This study involved 313 patients diagnosed with type 2 diabetes mellitus (T2DM) at two Malaysian tertiary hospitals. Socio-demographic data were assessed using a pre-tested interviewer-administered structured questionnaire. Anthropometric measurements were carried out according to standard protocols. Clinical and laboratory characteristics were examined. Kappa (k) statistics were used for the agreement between the four MetS definitions. The overall prevalence rates of MetS (95% CI) were 95.8% (93.6-98.1), 96.1% (94.0-98.3), 84.8% (80.8-88.9) and 97.7% (96.1-99.4) according to the WHO, NCEP ATP III, IDF and the Harmonized definitions, respectively. The Kappa statistics demonstrated a slight to substantial agreement between the definitions (k = 0.179-0.875, p k = 0.875, p hest specificity (100%) in identifying MetS. In conclusion, the new Harmonized criteria established the highest prevalence of MetS among the four definitions applied. There was a very good concordance between the WHO and NCEP ATP III criteria. The extremely high prevalence of MetS observed in type 2 diabetic patients indicates an impending pandemic of CVD risk in Malaysia. Aggressive treatment of MetS components is required to reduce cardiovascular risk in T2DM. 展开更多
关键词 Metabolic Syndrome TYPE 2 DIABETES Mellitus (T2DM) World Health Organization (WHO) Third Report of the National CHOLESTEROL Education Expert Panel on Detection Evaluation Treatment of High Blood CHOLESTEROL in Adults (NCEP ATP III) International DIABETES Federation (IDF) Harmonized definition
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Higher Variations of the Monty Hall Problem (3.0, 4.0) and Empirical Definition of the Phenomenon of Mathematics, in Boole’s Footsteps, as Something the Brain Does 被引量:1
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作者 Leo Depuydt Richard D. Gill 《Advances in Pure Mathematics》 2012年第4期243-273,共31页
In Advances in Pure Mathematics (www.scirp.org/journal/apm), Vol. 1, No. 4 (July 2011), pp. 136-154, the mathematical structure of the much discussed problem of probability known as the Monty Hall problem was mapped i... In Advances in Pure Mathematics (www.scirp.org/journal/apm), Vol. 1, No. 4 (July 2011), pp. 136-154, the mathematical structure of the much discussed problem of probability known as the Monty Hall problem was mapped in detail. It is styled here as Monty Hall 1.0. The proposed analysis was then generalized to related cases involving any number of doors (d), cars (c), and opened doors (o) (Monty Hall 2.0) and 1 specific case involving more than 1 picked door (p) (Monty Hall 3.0). In cognitive terms, this analysis was interpreted in function of the presumed digital nature of rational thought and language. In the present paper, Monty Hall 1.0 and 2.0 are briefly reviewed (§§2-3). Additional generalizations of the problem are then presented in §§4-7. They concern expansions of the problem to the following items: (1) to any number of picked doors, with p denoting the number of doors initially picked and q the number of doors picked when switching doors after doors have been opened to reveal goats (Monty Hall 3.0;see §4);(3) to the precise conditions under which one’s chances increase or decrease in instances of Monty Hall 3.0 (Monty Hall 3.2;see §6);and (4) to any number of switches of doors (s) (Monty Hall 4.0;see §7). The afore-mentioned article in APM, Vol. 1, No. 4 may serve as a useful introduction to the analysis of the higher variations of the Monty Hall problem offered in the present article. The body of the article is by Leo Depuydt. An appendix by Richard D. Gill (see §8) provides additional context by building a bridge to modern probability theory in its conventional notation and by pointing to the benefits of certain interesting and relevant tools of computation now available on the Internet. The cognitive component of the earlier investigation is extended in §9 by reflections on the foundations of mathematics. It will be proposed, in the footsteps of George Boole, that the phenomenon of mathematics needs to be defined in empirical terms as something that happens to the brain or something that the brain does. It is generally assumed that mathematics is a property of nature or reality or whatever one may call it. There is not the slightest intention in this paper to falsify this assumption because it cannot be falsified, just as it cannot be empirically or positively proven. But there is no way that this assumption can be a factual observation. It can be no more than an altogether reasonable, yet fully secondary, inference derived mainly from the fact that mathematics appears to work, even if some may deem the fact of this match to constitute proof. On the deepest empirical level, mathematics can only be directly observed and therefore directly analyzed as an activity of the brain. The study of mathematics therefore becomes an essential part of the study of cognition and human intelligence. The reflections on mathematics as a phenomenon offered in the present article will serve as a prelude to planned articles on how to redefine the foundations of probability as one type of mathematics in cognitive fashion and on how exactly Boole’s theory of probability subsumes, supersedes, and completes classical probability theory. §§2-7 combined, on the one hand, and §9, on the other hand, are both self-sufficient units and can be read independently from one another. The ultimate design of the larger project of which this paper is part remains the increase of digitalization of the analysis of rational thought and language, that is, of (rational, not emotional) human intelligence. To reach out to other disciplines, an effort is made to describe the mathematics more explicitly than is usual. 展开更多
关键词 Artificial INTELLIGENCE Binary Structure BOOLEAN ALGEBRA BOOLEAN Operators Booles ALGEBRA Brain Science Cognition Cognitive Science definitION of MATHEMATICS definitION of Probability Theory Digital MATHEMATICS Electrical Engineering Foundations of MATHEMATICS Human INTELLIGENCE Linguistics Logic Monty HALL Problem Neuroscience Non-quantitative and Quantitative MATHEMATICS Probability Theory Rational Thought and Language
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Partial Formalization: An Approach for Critical Analysis of Definitions and Methods Used in Bulk Extraction-Based Molecular Microbial Ecology
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作者 Donald A. Klein 《Open Journal of Ecology》 2015年第8期400-407,共8页
Partial formalization, which involves the development of deductive connections among statements, can be used to examine assumptions, definitions and related methodologies that are used in science. This approach has be... Partial formalization, which involves the development of deductive connections among statements, can be used to examine assumptions, definitions and related methodologies that are used in science. This approach has been applied to the study of nucleic acids recovered from natural microbial assemblages (NMA) by the use of bulk extraction. Six pools of bulk-extractable nucleic acids (BENA) are suggested to be present in a NMA: (pool 1) inactive microbes (abiotic-limited);(pool 2) inactive microbes (abiotic permissive, biotic-limited);(pool 3) dormant microbes (abiotic permissive, biotic-limited, but can become biotic permissive);(pool 4) in situ active microbes (the microbial community);(pool 5) viruses (virocells/virions/cryptic viral genomes);and (pool 6) extracellular nucleic acids including extracellular DNA (eDNA). Definitions for cells, the microbial community (in situ active cells), the rare biosphere, dormant cells (the microbial seed bank), viruses (virocells/virions/cryptic viral genomic), and diversity are presented, together with methodology suggested to allow their study. The word diversity will require at least 4 definitions, each involving a different methodology. These suggested definitions and methodologies should make it possible to make further advances in bulk extraction-based molecular microbial ecology. 展开更多
关键词 Abiotic ENVELOPE Baas Becking Biotic ENVELOPE BULK EXTRACTION Cells Community definitions Dormancy Methodology MICROBIAL Diversity MICROBIAL Seed Bank Natural MICROBIAL Assemblages PARTIAL FORMALIZATION Rare Biosphere
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一种新的宏、细观变形全场测量方法(英文) 被引量:1
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作者 王世斌 李翔宇 +6 位作者 佟景伟 P.Goudeau 王志勇 李林安 沈珉 岳澄 李鸿琦 《实验力学》 CSCD 北大核心 2005年第1期65-71,共7页
基于光学干涉和衍射理论,提出了一种新的用于宏、细观面内变形测量的光学方法。利用三束准直相干光之间的干涉,分别得到面内位移U+V和U-V的两幅耦合条纹图。借助于FFT相移技术,直接计算出全场的U和V分布。本实验系统中包含有长距离显微... 基于光学干涉和衍射理论,提出了一种新的用于宏、细观面内变形测量的光学方法。利用三束准直相干光之间的干涉,分别得到面内位移U+V和U-V的两幅耦合条纹图。借助于FFT相移技术,直接计算出全场的U和V分布。本实验系统中包含有长距离显微镜,三光束系统,数字图像采集和处理系统等。它具有光路简单,避开条纹级次的确定,直接计算得到U、V场等优点。将它用于热塑性复合材料 56层板AS4/PEEK[0/±45/90]7S三点弯曲梁位移场的宏、细观测量。得到了层间的变形规律。本文还利用三维各向异性弹性有限元法对AS4/PEEK[0/±45/90]7S三点弯曲梁进行了数值计算,得到了自由表面的位移场和应变场的数值解。定量分析了层间的变形传递规律,有助于进一步分析AS4/PEEK[0/±45/90]7S层合板宏、细观变形。 展开更多
关键词 FF
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Role of Flexible Macro Fibre Composite (MFC) Actuator on Bragg Wavelength Tuning in Microstructure Polymer Optical Fibre Long Period Grating for Strain Sensing Applications
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作者 Asok K. Dikshit Akhil Raj V. L. 《Journal of Sensor Technology》 2013年第3期75-83,共9页
The microstructure polymer optical fibre (mPOF) inscribed long period grating (LPG) offers a wide field of application in strain sensors arena within the materials elastic limit. Flexible innovative macro fibre compos... The microstructure polymer optical fibre (mPOF) inscribed long period grating (LPG) offers a wide field of application in strain sensors arena within the materials elastic limit. Flexible innovative macro fibre composite (MFC) actuator generates electromechanical force under DC driving voltage. We propose a novel method for Bragg wavelength blue shifting through stretch tuning of mPOF LPG in axial direction under applied DC voltage on attached MFC with LPG. The grating period of mPOF LPG changes refractive index and causes blue shift of Bragg grating fibre wavelength. The shifting governs on the values of generated electromechanically strain transfer from flexible MFC to mPOF LPG and they have potential applications in strain sensor. 展开更多
关键词 Microstructure POLYMER Optical FIBRE (mPOF) Long Period Grating (LPG) macro FIBRE COMPOSITE (MFC) ACTUATOR Strain Sensing Blue Shifting
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Comparative efficacy and safety between endoscopic submucosal dissection,surgery and definitive chemoradiotherapy in patients with cT1N0M0 esophageal cancer
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作者 Shu-Ai Luo Yu-Ying Sun +1 位作者 Ya-Ting Zeng Chun-Yu Huang 《World Journal of Gastrointestinal Endoscopy》 2024年第2期72-82,共11页
BACKGROUND Endoscopic submucosal dissection(ESD)and surgical resection are the standard of care for cT1N0M0 esophageal cancer(EC),whereas definitive chemoradiotherapy(d-CRT)is a treatment option.Nevertheless,the compa... BACKGROUND Endoscopic submucosal dissection(ESD)and surgical resection are the standard of care for cT1N0M0 esophageal cancer(EC),whereas definitive chemoradiotherapy(d-CRT)is a treatment option.Nevertheless,the comparative efficiency and safety of ESD,surgery and d-CRT for cT1N0M0 EC remain unclear.AIM To compare the efficiency and safety of ESD,surgery and d-CRT for cT1N0M0 EC.METHODS We retrospectively analyzed the hospitalized data of a total of 472 consecutive patients with cT1N0M0 EC treated at Sun Yat-sen University Cancer center between 2017-2019 and followed up until October 30th,2022.We analyzed demographic,medical recorded,histopathologic characteristics,imaging and endoscopic,and follow-up data.The Kaplan-Meier method and Cox proportional hazards modeling were used to analyze the difference of survival outcome by treatments.Inverse probability of treatment weighting(IPTW)was used to minimize potential confounding factors.RESULTS We retrospectively analyzed patients who underwent ESD(n=99)or surgery(n=220)or d-CRT(n=16)at the Sun Yat-sen University Cancer Center from 2017 to 2019.The median follow-up time for the ESD group,the surgery group,and the d-CRT group was 42.0 mo(95%CI:35.0-60.2),45.0 mo(95%CI:34.0-61.75)and 32.5 mo(95%CI:28.3-40.0),respectively.After adjusting for background factors using IPTW,the highest 3-year overall survival(OS)rate and 3-year recurrence-free survival(RFS)rate were observed in the ESD group(3-year OS:99.7% and 94.7% and 79.1%;and 3-year RFS:98.3%,87.4% and 79.1%,in the ESD,surgical,and d-CRT groups,respectively).There was no difference of severe complications occurring between the three groups(P≥0.05).Multivariate analysis showed that treatment method,histology and depth of infiltration were independently associated with OS and RFS.CONCLUSION For cT1N0M0 EC,ESD had better long-term survival and lower hospitalization costs than those who underwent d-CRT and surgery,with a similar rate of severe complications occurring. 展开更多
关键词 Retrospective study cT1N0M0 Esophageal squamous cell carcinoma Endoscopic submucosal dissection SURGERY definitive chemoradiotherapy
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水安全定义及其评价指数的应用 被引量:109
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作者 张翔 夏军 贾绍凤 《资源科学》 CSSCI CSCD 北大核心 2005年第3期145-149,共5页
随着社会经济的不断发展,资源短缺、人口增长和环境退化等压力日益增加,由此导致的安全问题已超越了传统的国家或公众安全的研究范畴,包括环境变化在内的综合安全研究势在必行,水资源及水生态环境的变化对社会经济发展的影响应纳入综合... 随着社会经济的不断发展,资源短缺、人口增长和环境退化等压力日益增加,由此导致的安全问题已超越了传统的国家或公众安全的研究范畴,包括环境变化在内的综合安全研究势在必行,水资源及水生态环境的变化对社会经济发展的影响应纳入综合安全的研究范畴。本文分析了环境变化与安全问题的本质联系,探讨了水安全的内涵,提出了水安全的定义;针对水安全评价问题,介绍了英国生态与水文中心提出的水贫穷指数,以及该指数监测水资源状况和水行业发展态势的应用情况,将水贫穷指数应用于海河流域,得出海河流域的水贫穷指数为46 6,表明海河流域的水安全状况处于中等程度,基本符合海河流域的实际情况,表明该指数具有一定的实用性,为研究并提出适合我国国情的水安全评价方法提供了有益的借鉴。 展开更多
关键词 退
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精密微塑性成形系统的研制 被引量:14
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作者 王春举 曲东升 +3 位作者 周健 单德彬 郭斌 孙立宁 《锻压技术》 CAS CSCD 北大核心 2005年第3期56-59,共4页
随着微型零件尺寸的减小,对成形设备提出了更高要求,传统的塑性成形设备难以在小行程下实现载荷和位移的精确控制。针对微成形的特点研制了精密微塑性成形系统,设计了宏动/微动相结合的驱动系统,微动部分使用压电陶瓷作为驱动器,宏动部... 随着微型零件尺寸的减小,对成形设备提出了更高要求,传统的塑性成形设备难以在小行程下实现载荷和位移的精确控制。针对微成形的特点研制了精密微塑性成形系统,设计了宏动/微动相结合的驱动系统,微动部分使用压电陶瓷作为驱动器,宏动部分采用精密丝杠旋钮来实现,借助数据采集系统进行数据的实时采集和处理,使用成形工艺控制器对微成形过程进行精确控制,该系统可以对模具进行加热以实现等温成形,由温度PID控制器控制。使用该精密微塑性成形系统进行了微成形试验,所成形的微型齿轮零件质量良好。 展开更多
关键词 PID 齿
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A Matrix Inequality for the Inversions of the Restrictions of a Positive Definite Hermitian Matrix
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作者 Weixiong Mai Mo Yan +2 位作者 Tao Qian Matteo Dalla Riva Saburou Saitoh 《Advances in Linear Algebra & Matrix Theory》 2013年第4期55-58,共4页
We exploit the theory of reproducing kernels to deduce a matrix inequality for the inverse of the restriction of a positive definite Hermitian matrix.
关键词 Reproducing Kernel POSITIVE definite HERMITIAN MATRIX Quadratic Inequality Inversion of POSITIVE definite HERMITIAN MATRIX Restriction of POSITIVE definite HERMITIAN MATRIX SCHUR Complement Block MATRIX
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鸡公山自然保护区森林生物量动态模拟及其宏观价值评估 被引量:6
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作者 李海涛 杨柳春 +4 位作者 严茂超 董孝斌 胡聃 张照喜 杜化堂 《资源科学》 CSSCI CSCD 北大核心 2005年第4期154-159,共6页
本文运用鸡公山科学考察资料及1991年森林资源清查资料,采用森林材积源生物量推算方法研究了鸡公山森林生物量及其净生物量的现状,并对生物量的动态变化规律及其宏观价值进行模拟评估。研究结果表明:1991年鸡公山森林生物量为20·1&... 本文运用鸡公山科学考察资料及1991年森林资源清查资料,采用森林材积源生物量推算方法研究了鸡公山森林生物量及其净生物量的现状,并对生物量的动态变化规律及其宏观价值进行模拟评估。研究结果表明:1991年鸡公山森林生物量为20·1×104t,平均森林生物量为70t/hm2,略低于全国平均水平(77·4t/hm2);单位面积的净生产力为14·31t/(hm2·年),鸡公山自然保护区森林的总净生产力4·1×104t/年。从总体上看,鸡公山的森林以中幼龄林为主体,马尾松、杉木和栎类林木的平均生物量较低,分别为35·7Mg/hm2、46·2Mg/hm2和64·8Mg/hm2,而次生阔杂林的平均生物量相对较高,为124·2Mg/hm2。马尾松林、杉木和栎类林的平均生物量较低,这一方面说明这类林木的质量较差,幼龄林和残次林较多,但从另一个侧面也反映了如果对现有森林加以更好的抚育管理,鸡公山森林还有很大的潜力。鸡公山森林生物量的动态模拟结果表明,鸡公山的生物量有巨大增长潜力,加强保护,生物量可从1991年的20×104t增加到2030年的36×104t。根据能值理论与方法对生物量的宏观经济价值评估,生物量的宏观经济价值也会从1991年的5552×104美元增加到2030年的10000×104美元。 展开更多
关键词 1991 2030
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The Logic and Fundamental Concepts of the Grand Unified Theory
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作者 Edgar E. Escultura 《Journal of Modern Physics》 2013年第8期213-222,共10页
The grand unified theory (GUT) originated in mathematics with this question: why are there long standing unsolved problems in mathematics, e.g., Fermat’s conjecture (also known as Fermat’s last theorem (FLT))? The a... The grand unified theory (GUT) originated in mathematics with this question: why are there long standing unsolved problems in mathematics, e.g., Fermat’s conjecture (also known as Fermat’s last theorem (FLT))? The answer came quickly: its underlying fields—foundations and the real number system—are defective. In particular, formal logic is inapplicable to mathematics (language of science) and the real number system is inconsistent. Critique-rectification of these fields was undertaken leading to a new mathematical methodology and the consistent new real number system that provides the main mathematics of GUT. Similar question was posed in physics: why are there long standing problems, e.g., the gravitational n-body and turbulence problems? The answer: the present methodology, quantitative modeling is inadequate and the remedy is a new methodology—qualitative mathematics and modeling that solved these problems and provided the initial formulation of GUT. This paper presents the basic logic of GUT and its fundamental concepts, particularly, the superstring or fundamental building block of matter. 展开更多
关键词 Anti-Matter Big Bang Black Hole Chaos COSMIC BURST COSMOLOGICAL Body Electromagnetic Wave Generalized Physical FRACTAL Qualitative Modeling Quantum and macro Gravity QUARK Primum SUPERSTRING Turbulence
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基准站GPS连续观测得到的垂直位移时间序列 被引量:29
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作者 顾国华 《地震地质》 EI CSCD 北大核心 2005年第2期332-340,共9页
利用1998年9月至2004年3月上旬中国地壳运动观测网络基准站GPS连续观测结果所获得的垂直位移时间序列,讨论了基准的选择,分析了基准站垂直位移的特点。取中国东部一组垂直位移变化形态基本一致、年速率较小的6个基准站作为垂直位移时间... 利用1998年9月至2004年3月上旬中国地壳运动观测网络基准站GPS连续观测结果所获得的垂直位移时间序列,讨论了基准的选择,分析了基准站垂直位移的特点。取中国东部一组垂直位移变化形态基本一致、年速率较小的6个基准站作为垂直位移时间序列的基准。计算结果表明,每周的垂直位移解的精度可达3mm。与基准站的水平位移年速率相比,垂直位移年速率普遍较低;而与基准站的水平位移时间序列相比,一些基准站的垂直位移时间序列有非常显著的年周期变化,幅度达20~50mm。中国大陆西部基准站的年周期变化与地球自转有明显的相关性,并且符合地球自转守恒。基准站垂直位移的变化值得多方面深入研究。 展开更多
关键词 GPS 20043 1998
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基于箭形累积损伤的裂纹尖端力学:奇异性分级和多尺度分段 被引量:2
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作者 薛昌明 吴永礼(译) 《力学进展》 EI CSCD 北大核心 2010年第2期203-229,共27页
在适度的空间和时间尺度组合下,裂纹既可在几个月中蠕变几个纳米,也能在几秒钟内扩展10km.虽然裂纹的尖端没有实际的质量,但是它能通过激活周围的物质而处于高能量状态.依赖于材料的损伤方向,激活质量的减少和增加可发生在尺度转变之前... 在适度的空间和时间尺度组合下,裂纹既可在几个月中蠕变几个纳米,也能在几秒钟内扩展10km.虽然裂纹的尖端没有实际的质量,但是它能通过激活周围的物质而处于高能量状态.依赖于材料的损伤方向,激活质量的减少和增加可发生在尺度转变之前或之后.每个尺度区的分段阈值被假定为与裂纹尖端速度的平方a^2和激活质量密度M的乘积有关:W=M_(↓↑)a_(↑↓)~2和D=M^(↓↑)a_(↑↓)~2.W和D分别被称为直接吸收和自耗散能量密度.正如下标/上标符号所示,激活的质量密度M_(↓↑)和M^(↓↑)与裂纹尖端速度a变化趋势相反,既可增加也可减少.a^2和M的互补效应隐含着常用于宇宙物理学建模的膨胀和/或收缩的物理过程.在用于尺度敏感的裂纹尖端的行为时,激活的质量密度有相同的解释.分段时的多尺度可以由…皮观、纳观、微观和宏观…组成.因此,形象地说,材料损伤过程可以通过裂纹扩展过程中非均匀的总体和局部能量的传递来模拟.疲劳裂纹扩展引起的材料损伤被用来阐释由大到小和由慢到快的尺度/时间序,热力学中的冷→热和有序→无序转换.这一过程正巧与宇宙演化的箭形方向相反,宇宙演化遵循小→大和快→慢,而热力学相反,遵循热→冷和无序→有序.为了表示由损伤萌生所造成的类裂缝型缺陷的不均匀性,提出了一个被称为裂纹尖端力学(crack tip mechanics,CTM)的新模式.涉及的范围是模拟原子列之间的界面裂纹或连续体中分叉的切口.假如需要的话,尺寸和时间的范围可以复盖从皮观到宏观甚至更大.虽然采用疲劳裂纹来说明CTM的基本原理,在宇宙物理学背景中与直接吸收和自耗散相关的膨胀和收缩的情况可以描述裂纹周围激活质量的行为,它们可看为能量的汇或源.奇异性被用来捕获能量的源或汇的特性,物理上,两者作为界面的一部分,从数学上看则是不连续的线的一部分.能量从一种形式变为另一种形式取决于能量吸收或耗散的箭形损伤时间,这之中牵涉到尺度分段和奇异性强度的联合应用.材料组分随时间的劣化是根据指定的设计寿命导出的,从而使材料的响应与加载率的时间历史匹配.2024-T3铝板的皮观/纳观/微观/宏观开裂模型用来说明什么地方可以增加结构的寿命部分.皮观/纳观/微观/宏观/结构系统的性能随时间劣化可以用9个尺度转变物理参数来描述:纳观/微观区有3个(μ_(na/mi)~*,σ_(na/mi)~*,d_(na/mi)~*),微观/宏观区有3个(μ_(mi/ma)~*,σ_(mi/ma)~*,d_(mi/ma)~*),皮观/纳观区有3个(μ_(pi/na)~*,σ_(pi/na)~*,d_(pi/na)~*).下标pi,na,mi,ma和struc分别表示皮观、纳观、微观、宏观和结构.只要知道两个相连的尺度敏感参数,在较低尺度的时间相关的局部物理参数就完成了分析连续体的形式论,虽然它们并不需要用实验来知道.更具体地说,根据皮观→纳观→微观→宏观分别有1.25/1.00/0.75/0.50的λ奇异性强度,皮观裂纹、纳观裂纹、微观裂纹和宏观裂纹的转变特征是从时间箭形的指定的寿命预期来确定的.附加的0.25强度的奇异性可用于结构元件.回想起来,λ=0.5相应于断裂力学中的应力分量与r^(0.5)成反比,r是与宏观裂纹尖端的距离.微观裂纹、纳观裂纹和皮观裂纹分别赋予r^(-0.75),r^(-1.0),r^(-1.25)的奇异性.箭形时间(以年为单位)取决于问题的定义.设备的关键部件可用1.5~±/2.5~±/3.5~±/5.5~±寿命分布和总寿命为13~±年(a)的皮观/纳观/微观/宏观尺度来设计运行.上标±表示多于或少于实际运行的时间.累进损伤被假定为发生在皮观→纳观→微观→宏观方向.同样的方案用于20年总寿命的2024-T3铝板的疲劳损伤,按照1.5~±/2.5~±/3.5~±/5.5~±/7.0~±的方式将它的寿命分布在皮观、纳观、微观、宏观和结构的尺度上,这样的指定只是满足在每个尺度范围内损伤内部材料结构所用的能量匹配,因此可以强制执行在总寿命的跨度内精确的时间相关的材料性能劣化过程. 展开更多
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界定西藏冻融侵蚀区分布的一种新方法 被引量:27
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作者 张建国 刘淑珍 《地理与地理信息科学》 CSSCI CSCD 北大核心 2005年第2期32-34,47,共4页
冻融侵蚀区的界定是目前青藏高原冻融侵蚀研究需要解决的重要课题之一。根据笔者和前人相关成果,该文提出了青藏高原冻融侵蚀区界定的理论依据,并在GIS技术支持下,对青藏高原的主体———西藏自治区的冻融侵蚀进行界定,系统分析西藏冻... 冻融侵蚀区的界定是目前青藏高原冻融侵蚀研究需要解决的重要课题之一。根据笔者和前人相关成果,该文提出了青藏高原冻融侵蚀区界定的理论依据,并在GIS技术支持下,对青藏高原的主体———西藏自治区的冻融侵蚀进行界定,系统分析西藏冻融侵蚀区的分布规律。西藏自治区冻融侵蚀区分布具有以下特点:1)冻融侵蚀区分布面积广,占西藏自治区国土面积的55 3%;2)雅江南北冻融侵蚀区分布差异明显,雅江以北分布范围广,雅江以南范围小;3)地区分布差异明显,冻融侵蚀区集中分布在那曲和阿里地区;4)冻融侵蚀是那曲、阿里、拉萨、昌都、日喀则等地区(市)最主要的土壤侵蚀类型。 展开更多
关键词 西 GIS
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Seasonal and Spatial Variations of Macro Benthos in the Intertidal Mudflat of Southern Yellow River Delta,China in 2007/2008 被引量:2
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作者 ZOU Li YAO Xiao +4 位作者 YAMAGUCHI Hitomi GUO Xinyu GAO Huiwang WANG Kai SUN Mingyi 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第2期437-444,共8页
In order to examine the seasonal and spatial distributions of benthic animals in the intertidal mudflat of the southern Yellow River Delta,field investigations were carried out in 2007 and 2008 and multiple methods we... In order to examine the seasonal and spatial distributions of benthic animals in the intertidal mudflat of the southern Yellow River Delta,field investigations were carried out in 2007 and 2008 and multiple methods were applied.Results showed that,the biomass of macro benthos ranged at 0.75-1151.00 g wet m^(-2) and averaged at 156.31 g wet m^(-2),in which Mactra veneriformis accounted for 75.6%-93.4% of the total macro benthic biomass.More than 90% of macro benthos inhabited in the middle and low tide lines,and higher biomass occurred in early summer and lower in winter.Statistical analysis showed that:1)M.veneriformis growth was primarily favored at higher temperature and lower salinity;2)after long time interaction,benthic bivalve grazers led to patching distributions of Chlorophyll a(Chl a);3)macro benthic biomass positively related with Chl a when the concentration of Chl a was low,but they were negatively related when Chl a concentration was high;and 4)furthermore,the biomass of benthic bivalves peaked in the sediment with median grain size about 0.55 mm,but decreased gradually in coarse or fine sediments.The secondary productivity ranged at 0.37-283.68 g m^(-2)yr^(-1) and averaged at 47.88 g m^(-2) yr^(-1),in which 69.7% was contributed by M.veneriformis It was estimated that primary production was transformed to secondary production at a rate of 6.87%approximately,which implies that there is a local sustainability of high bivalve production. 展开更多
关键词 macro BENTHOS Mactra veneriformis distribution INTERTIDAL MUDFLAT SOUTHERN Yellow River Delta
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Can optical diagnosis of small colon polyps be accurate? Comparing standard scope without narrow banding to high definition scope with narrow banding 被引量:1
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作者 Hassan Ashktorab Firoozeh Etaati +8 位作者 Farahnaz Rezaeean Mehdi Nouraie Mansour Paydar Hassan Hassanzadeh Namin Andrew Sanderson Rehana Begum Kawtar Alkhalloufi Hassan Brim Adeyinka O Laiyemo 《World Journal of Gastroenterology》 SCIE CAS 2016年第28期6539-6546,共8页
AIM: To study the accuracy of using high definition(HD) scope with narrow band imaging(NBI) vs standard white light colonoscope without NBI(ST), to predict the histology of the colon polyps, particularly those < 1 ... AIM: To study the accuracy of using high definition(HD) scope with narrow band imaging(NBI) vs standard white light colonoscope without NBI(ST), to predict the histology of the colon polyps, particularly those < 1 cm.METHODS: A total of 147 African Americans patients who were referred to Howard University Hospital for screening or, diagnostic or follow up colonoscopy, during a 12-mo period in 2012 were prospectively recruited. Some patients had multiple polyps and total number of polyps was 179. Their colonoscopies were performed by 3 experienced endoscopists who determined the size and stated whether the polyps being removed were hyperplastic or adenomatous polyps using standard colonoscopes or high definition colonoscopes with NBI. The histopathologic diagnosis was reported by pathologists as part of routine care. RESULTS: Of participants in the study, 55(37%) were male and median(interquartile range) of age was 56(19-80). Demographic, clinical characteristics, past medical history of patients, and the data obtained by two instruments were not significantly different and two methods detected similar number of polyps. In ST scope 89% of polyps were < 1 cm vs 87% in HD scope(P = 0.7). The ST scope had a positive predictive value(PPV) and positive likelihood ratio(PLR) of 86% and 4.0 for adenoma compared to 74% and 2.6 for HD scope. There was a trend of higher sensitivity for HD scope(68%) compare to ST scope(53%) with almost the same specificity. The ST scope had a PPV and PLR of 38% and 1.8 for hyperplastic polyp(HPP) compared to 42% and 2.2 for HD scope. The sensitivity and specificity of two instruments for HPP diagnosis were similar.CONCLUSION: Our results indicated that HD scope was more sensitive in diagnosis of adenoma than ST scope. Clinical diagnosis of HPP with either scope is less accurate compared to adenoma. Colonoscopy diagnosis is not yet fully matched with pathologic diagnosis of colon polyp. However with the advancement of both imaging and training, it may be possible to increase the sensitivity and specificity of the scopes and hence save money for eliminating time and the cost of Immunohistochemistry/pathology. 展开更多
关键词 High definition COLONOSCOPY Narrow band imaging POLYP detection COLON cancer screening
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互助型创伤急救模式下确定性救命手术的探讨 被引量:3
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作者 张宪 张建波 +5 位作者 何忠杰 刘波 马俊勋 彭国球 赵晓东 党伟 《感染.炎症.修复》 2006年第1期30-33,共4页
目的:探讨互助型创伤急救模式下确定性救命手术的规律及其现实意义。方法:建立由急救医师以“白金十分钟”的理念对病人进行链式流程复苏、由专科医师实行确定性救命手术的互助型创伤小组工作模式,总结分析1993年-2005年2428例中等严重... 目的:探讨互助型创伤急救模式下确定性救命手术的规律及其现实意义。方法:建立由急救医师以“白金十分钟”的理念对病人进行链式流程复苏、由专科医师实行确定性救命手术的互助型创伤小组工作模式,总结分析1993年-2005年2428例中等严重度以上的急诊创伤病例。结果:伤员构成:男1882例,女546例,男女比例为3.45:1;年龄30.5±17.2岁(4-86岁);创伤评分(TS)11.5±3.5、CRAMS评分7.46±2.4;严重度:中度(ISS≤13)1250例(51.5%)、重度(ISS≥13-25)838例(34.5%)、极重度(ISS≥25)40(14.0%)。合并伤:复合伤29例(1.2%),多发伤687例(28.3%),休克1076例(44.3%),其中创伤性休克767(31.6%),失血性休克309 (12.7%);死亡197例(8.1%),其中主要引起死亡的原因按脏器分类:脑140例(71.1%),腹45例(22.8%),胸8例(4.1%),大血管4例(2.0%);抢救互助情况:急救部完成急救手术481例,急救部+专科手术1440例,急救部+SICU完成507例。结论:互助型创伤急救模式在当前城市创伤救治中仍具有普遍意义,加强急救与专科的密切协作是救治成功关键。 展开更多
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Chaos, Turbulence and Fractal: Theory and Applications
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作者 Edgar E. Escultura 《International Journal of Modern Nonlinear Theory and Application》 2013年第3期176-185,共10页
The paper identifies chaos, turbulence and fractal of quantum and macro gravity and studies their behavior, properties and applications based on the grand unified theory (GUT) and qualitative mathematics and modeling.... The paper identifies chaos, turbulence and fractal of quantum and macro gravity and studies their behavior, properties and applications based on the grand unified theory (GUT) and qualitative mathematics and modeling. Applications include devising electromagnetic engines, tornado aborter and terminator and technologies for electromagnetic treatment of genetic diseases such as cancer, systemic lupos erythematosus, diabetes and mental disorder without harm to normal cell and side effect. Typhoon in the Western Pacific which is turbulence is impossible to terminate and impractical to deflect but prediction can be improved because it follows the Northern Pacific Wind Cycle (Southern Pacific Wind Cycle in the Southern Hemisphere) and is affected by the temperature variation over the Philippine Deep and around Mayon Volcano. The electromagnetic engine uses the clean, inexhaustible, free dark matter, specifically, the energy of magnetic flux, in place of conventional fuel, e.g., fossil, nuclear and geothermal. The tornado aborter and terminator utilize the gravitational flux of the Earth, its vortex flux of superstrings as a cosmological vortex which is turbulence. The technologies for electromagnetic treatment of genetic diseases utilize electromagnetic waves based on resonance. All of them are GUT technologies because they are applications of GUT. Except for the magnetic train which is in operation the rest is still at the conceptual and research and development (R&D) phase but the theory is complete and the strategy for R&D are laid down in detail in the cited original papers. 展开更多
关键词 CHAOS Cosmological Vortex Dark Matter ELECTROMAGNETIC Engine ELECTROMAGNETIC Treatment of Genetic Diseases FRACTAL Gravitational FLUX Magnetic FLUX Prima Quantum and macro Gravity SUPERSTRING Toroidal FLUX TURBULENCE
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绿色行政的定位、价值及其实施路径 被引量:11
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作者 刘铮 雷志松 《江汉大学学报(社会科学版)》 2005年第2期10-13,共4页
绿色行政是一种新的依法行政理念,它包含行政权限、行政民主、监督责任等丰富的内涵。绿色行政对促进绿色制度创新、弘扬民族绿色文化、规范环境执法行为和推进行政管理绿色化具有重要作用。绿色行政的实施路径包括健全对环境管理环节... 绿色行政是一种新的依法行政理念,它包含行政权限、行政民主、监督责任等丰富的内涵。绿色行政对促进绿色制度创新、弘扬民族绿色文化、规范环境执法行为和推进行政管理绿色化具有重要作用。绿色行政的实施路径包括健全对环境管理环节的行政评估制度、推行国际环境管理标准、推行环境电子行政管理和实施绿色GDP等。 展开更多
关键词 绿 绿GDP 绿 绿
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中国新三大地带宏观区域格局的划分 被引量:43
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作者 刘勇 《地理学报》 EI CSCD 北大核心 2005年第3期361-370,共10页
随着区域经济社会的快速发展,中国现行三大地带的划分已难以适应新形势下统筹区域发展的要求。在全面介绍了完整的区域经济体系和美国4层次区域经济体系划分的基础上,按照科学发展观以及“五个统筹”的要求,提出了未来中国东北及东部沿... 随着区域经济社会的快速发展,中国现行三大地带的划分已难以适应新形势下统筹区域发展的要求。在全面介绍了完整的区域经济体系和美国4层次区域经济体系划分的基础上,按照科学发展观以及“五个统筹”的要求,提出了未来中国东北及东部沿海、中部及近西部和远西部等新的三大地带和东北、京津冀鲁沿海、沪苏浙沿海、粤闽琼沿海、黄河上中游、长江上中游、珠江上中游、内蒙古、新疆和青藏高原等10大综合经济区的划分方案。 展开更多
关键词 沿 西
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