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Journal of Integrative Plant Biology 2006年第1期48卷 85-98页

作者： David H. Burk Ruiqin Zhong w. herbert Morrison III Zheng-Hua Ye Department of Plant Biology University of Georgia Athens Georgia 30602 USA Richard B. Russell Agriculture Research Center U.S. Department of Agriculture Agricultural Research Service Athens Georgia 30604 USA

It has been known that the transverse orientation of cortical microtubules （MTs） along the elongation axis is essential for normal cell morphogenesis, but whether cortical MTs are essential for normal cell wall synthesis is still not clear. In the present study, we have investigated whether cortical MTs affect cell wall synthesis by direct alteration of the cortical MT organization in Arabidopsis thaliana. Disruption of the cortical MT organization by expression of an excess amount of green fluorescent protein-tagged a-tubulin 6 （GFP-TUA6） in transgenic Arabidopsis plants was found to cause a marked reduction in cell wall thickness and a de- crease in the cell wall sugars glucose and xylose. Concomitantly, the stem strength of the GFP-TUA6 overexpressors was markedly reduced compared with the wild type. In addition, expression of excess GFP- TUA6 results in an alteration in cell morphogenesis and a severe effect on plant growth and development. Together, these results suggest that the proper organization of cortical MTs is essential for the normal synthesis of plant cell walls.

关键词： Arabidopsis thaliana cell elongation cell wall synthesis cortical microtubules microtubule organization.

microRNAs: Fad or future of liver disease

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world Journal of Gastroenterology 2011年第20期17卷 2536-2542页

作者： Ashley M Lakner herbert L Bonkovsky Laura w Schrum Department of Biology University of North Carolina at Charlotte Liver Digestive and Metabolic Disorders Laboratory and the Liver-Biliary-Pancreatic Center Carolinas Medical Center Department of Medicine University of North Carolina at Chapel Hill Departments of Medicine and Molecular Microbial and Structural Biology University of Connecticut Health Center

microRNAs (miRs) are small non-coding RNAs that regulate both mRNA and protein expression of target genes, which results in alterations in mRNA stability or translation inhibition. miRs influence at least one third of all human transcripts and are known regulators of various important cellular growth and differentiation factors. miRs have recently emerged as key regulatory molecules in chronic liver disease. This review details recent contributions to the field of miRs that influence liver development and the broad spectrum of disease, from non-alcoholic fatty liver disease to fibrosis/cirrhosis, with particular emphasis on hepatic stellate cells and potential use of miRs as therapeutic tools.

关键词： Liver Fibrosis microRNA mRNA Hepatic stellate cells

Comparison of direct fecal smear microscopy,culture,and polymerase chain reaction for the detection of Blastocystis *** human stool samples

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Asian Pacific Journal of Tropical Medicine 2013年第10期6卷 780-784页

作者： herbert J Santos windell L Rivera Institute of Biology College of ScienceUniversity of the Philippines Molecular Protozoology Laboratory Natural Sciences Research InstituteUniversity of the Philippines

Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis *** human ***:Human stool samples were collected from a community in San Isidro,Rodriguez,Rizal,*** samples were subjected to direct fecal smear microscopy,culture and polymerase chain reaction to detect the presence of Blastocystis ***:Of the 110 stool samples collected,28(25%)were detected positive for the presence of Blastocystis *** two or more *** method detected the highest number of Blastocystis-positive stool samples(n=36),followed by PCR of DNA extracted from culture(n=26),PCR of DNA extracted from stool(n=10),and direct fecal smear(n=9).Compared to culture,the sensitivity of the other detection methods were 66.7%for PCR from culture and 19.4%for both PCR from stool and direct fecal *** of the methods was high,with PCR from culture and direct fecal smear having97.3%,while PCR from stool at 95.9%.Conclusions:In this study,in vitro culture is the best method for detecting Blastocystis *** human stool samples.

关键词： Blastocystis sp. Direct fecal smear Culture Polymerase chain reaction(PCR) Human stool Sensitivity Specificity

Molecular mapping of a novel wheat powdery mildew resistance gene Ml92145E8-9 and its application in wheat breeding by marker-assisted selection

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The Crop Journal 2018年第6期6卷 621-627页

作者： Xiaocheng Yu Shizhong Ren Lanfei Zhao Jun Guo Yinguang Bao Yingxue Ma Hongwei wang herbert w.Ohm Dazhao Yu Hongjie Li Lingrang Kong State Key Laboratory of Crop Biology College of AgronomyShandong Agricultural UniversityTai'an 271018ShandongChina Department of Agronomy Purdue UniversityWest LafayetteIN 47907-1150USA Hubei Academy of Agricultural Sciences Wuhan 430064HubeiChina Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China

Powdery mildew, caused by Blumeria graminis f. sp. tritici(Bgt), is one of the most devastating diseases of common wheat(Triticum aestivum L.). The wheat line 92145 E8-9 is immune to Bgt isolate E09. Genetic analysis reveals that the powdery mildew resistance in 92145 E8-9 is controlled by a single dominant gene, temporarily designated Ml92145 E8-9. Bulkedsegregant analysis(BSA) with simple sequence repeat(SSR) markers indicates that Ml92145 E8-9 is located on chromosome 2 AL. According to the reactions of 92145 E8-9,VPM1(Pm4 b carrier), and Lankao 906(PmLK906 carrier) to 14 Bgt isolates, the resistance spectrum of 92145 E8-9 differs from those of Pm4 b and PmLK906, both of which were previously localized to 2 AL. To test the allelism among Ml92145 E8-9, Pm4 b and PmLK906, two F2 populations of 92145 E8-9 × VPM1(Pm4 b) and 92145 E8-9 × Lankao 906(PmLK906) were developed in this study. Screening of 784 F2 progeny of 92145 E8-9 × VPM1 and 973 F2 progeny of 92145 E8-9 × Lankao 906 for Bgt isolate E09 identified 37 and 19 susceptible plants, respectively. These findings indicated that Ml92145 E8-9 is non-allelic to either Pm4 b or PmLK906. Thus, Ml92145 E8-9 is likely to be a new powdery mildew resistance gene on2 AL. New polymorphic markers were developed based on the collinearity of genomic regions of Ml92145 E8-9 with the reference sequences of the International wheat Genome Sequencing Consortium(IwGSC). Ml92145 E8-9 was mapped to a 3.6 c M interval flanked by molecular markers Xsdauk13 and Xsdauk682. This study also developed five powdery mildew-resistant wheat lines(SDAU3561, SDAU3562, SDAU4173, SDAU4174, and SDAU4175)using flanking marker-aided selection. The markers closely linked to Ml92145 E8-9 would be useful in marker-assisted selection for wheat powdery mildew resistance breeding.

关键词： Marker-assisted selection Ml92145E8-9 Powdery mildew Triticum aestivum L.

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结构方程模型中调节效应的标准化估计

心理学报 2008年第6期40卷 729-736页

作者：温忠麟侯杰泰 herbert w．Marsh 华南师范大学心理应用研究中心广州510631 香港考试及评核局香港香港中文大学教育心理系香港牛津大学教育系英国

回归分析和结构方程分析中,标准化估计对解释模型和比较效应大小有重要作用。对于调节效应模型(或交互效应模型),通常的标准化估计没有意义。虽然显变量的调节效应模型标准化估计问题已经解决,但潜变量的调节效应模型标准化估计问题复... 详细信息

回归分析和结构方程分析中,标准化估计对解释模型和比较效应大小有重要作用。对于调节效应模型(或交互效应模型),通常的标准化估计没有意义。虽然显变量的调节效应模型标准化估计问题已经解决,但潜变量的调节效应模型标准化估计问题复杂得多。本文先介绍回归分析中显变量调节效应模型的标准化估计,然后提出了一种通过参数的原始估计和通常标准化估计来计算潜变量调节效应模型的"标准化"估计的方法,得到的"标准化"估计是尺度不变的,说明可以用"标准化"估计来解释和比较主效应和调节效应。

关键词：结构方程调节效应标准化估计交互效应尺度不变性

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Decomposition of Mathematical Programming Models for Aircraft wing Design Facilitating the Use of Dynamic Programming Approach

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American Journal of Operations Research 2023年第5期13卷 111-131页

作者： Prashant K. Tarun herbert w. Corley Steven L. Craig School of Business Missouri Western State University St. Joseph Missouri USA Department of Industrial Manufacturing & Systems Engineering University of Texas at Arlington Arlington Texas USA

Aircraft designers strive to achieve optimal weight-reliability tradeoffs while designing an aircraft. Since aircraft wing skins account for more than fifty percent of their structural weight, aircraft wings must be designed with utmost care and attention in terms of material types and thickness configurations. In particular, the selection of thickness at each location of the aircraft wing skin is the most consequential task for aircraft designers. To accomplish this, we present discrete mathematical programming models to obtain optimal thicknesses either to minimize weight or to maximize reliability. we present theoretical results for the decomposition of these discrete mathematical programming models to reduce computer memory requirements and facilitate the use of dynamic programming for design purposes. In particular, a decomposed version of the weight minimization problem is solved for an aircraft wing with thirty locations (or panels) and fourteen thickness choices for each location to yield an optimal minimum weight design.

关键词： Aircraft wing Design Maximum Reliability Design Minimum weight Design Dynamic Programming Optimization Decomposition

A Dynamic Programming Approach to the Design of Composite Aircraft wings

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American Journal of Operations Research 2022年第5期12卷 194-207页

作者： Prashant K. Tarun herbert w. Corley Steven L. Craig School of Business Missouri Western State University St. Joseph USA Department of Industrial Manufacturing & Systems Engineering University of Texas at Arlington Arlington USA

A light and reliable aircraft has been the major goal of aircraft designers. It is imperative to design the aircraft wing skins as efficiently as possible since the wing skins comprise more than fifty percent of the structural weight of the aircraft wing. The aircraft wing skin consists of many different types of material and thickness configurations at various locations. Selecting a thickness for each location is perhaps the most significant design task. In this paper, we formulate discrete mathematical programming models to determine the optimal thicknesses for three different criteria: maximize reliability, minimize weight, and achieve a trade-off between maximizing reliability and minimizing weight. These three model formulations are generalized discrete resource-allocation problems, which lend themselves well to the dynamic programming approach. Consequently, we use the dynamic programming method to solve these model formulations. To illustrate our approach, an example is solved in which dynamic programming yields a minimum weight design as well as a trade-off curve for weight versus reliability for an aircraft wing with thirty locations (or panels) and fourteen thickness choices for each location.

关键词： Aircraft wing Design Maximum Reliability Design Minimum weight Design Dynamic Programming Multiple Objective Optimization Pareto Optimality

无均值结构的潜变量交互效应模型的标准化估计

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心理学报 2011年第10期43卷 1219-1228页

作者：吴艳温忠麟侯杰泰 herbert w.Marsh 广东外语外贸大学应用心理学系广州510420 华南师范大学心理应用研究中心广州510631 香港中文大学教育心理系牛津大学教育系

潜变量交互效应建模研究近年来有两项重要进展,一是提出了潜变量交互效应模型的标准化估计及其计算公式;二是发现无均值结构模型可以取代传统的有均值结构模型,建模大为简化。但标准化估计是在传统的有均值结构模型中建立的,在简化的模... 详细信息

潜变量交互效应建模研究近年来有两项重要进展,一是提出了潜变量交互效应模型的标准化估计及其计算公式;二是发现无均值结构模型可以取代传统的有均值结构模型,建模大为简化。但标准化估计是在传统的有均值结构模型中建立的,在简化的模型中同样适用吗?本文在无均值结构模型的框架内,给出了潜变量交互效应模型的标准化形式、计算公式和建模步骤,并通过模拟研究比较了极大似然和广义最小二乘两种估计方法、配对乘积指标和全部乘积指标两种指标类型,结果表明,在计算交互效应的标准化估计时,应当使用配对乘积指标建模,并且首选极大似然估计。

关键词：潜变量交互效应结构方程乘积指标估计方法

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薄层介质中的AVO计算误差

国外油气勘探 1992年第1期 46-58页

作者： herbert w.Swan 陈少娴

前不久,Spratt(1987)曾证明,AVO 分析对小的剩余速度误差可能是很敏感的。但是,由于动校正拉伸,作为炮检距函数的微分调谐误差、球面扩散以及震源和检波器的方向性组合等原因,即使能相当精确地确定速度时,AVO 畸变依然非常严重。业已发... 详细信息

前不久,Spratt(1987)曾证明,AVO 分析对小的剩余速度误差可能是很敏感的。但是,由于动校正拉伸,作为炮检距函数的微分调谐误差、球面扩散以及震源和检波器的方向性组合等原因,即使能相当精确地确定速度时,AVO 畸变依然非常严重。业已发现,假如零炮检距反射时间比子波宽度长得多,则所有这些误差可以用一个关于零炮检距反射时间的泰勒级数展开式表示。这个级数的第一项表示 Spratt 提出的剩余速度误差项,第二项则表示上面提到的所有其他影响。实际上,每项都可能比要估算的基本的隐含振幅变化大。例如,即使速度场是均匀和正确的,雷克子波拉伸也要导致 AVO 峰值误差达零炮检距最大反射的61%。这个结果与子波频率和分析中使用的入射角范围无关。动校速度的正梯度将加大这个误差,而在 AVO 分析之前对资料进行窄带滤波又将极大地展宽其时间延伸。在子波叠掩的薄目的层中,用静态时移代替正常时差校正以校直一具体反射可能消除拉伸,但不能消除微分调谐误差。

关键词：薄层反射振幅炮检距计算方法误差分析