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A Molecular Dynamics Simulation Study of Two Dipeptide based Molecular Micelles: Effect of Amino Acid Order

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Open Journal of Physical Chemistry 2013年第1期3卷 20-29页

作者： Kevin F. morris Eugene J. billiot Fereshteh H. billiot Kenny b. Lipkowitz William M. Southerland Yayin Fang Department of biochemistry and Molecular biology Howard University College of Medicine Howard University Washington USA Department of Chemistry Carthage College Kenosha USA Department of Physical and Environmental Sciences Texas A&M University-Corpus Christi Corpus Christi USA Office of Naval Research Arlington USA

Molecular dynamics (MD) simulations were used to compare the structures of the chiral molecular micelles (MM) poly-(sodium undecyl-(L,L)-leucine-valine) (poly(SULV)) and poly-(sodium undecyl-(L,L)-valine-leucine) (poly (SUVL)). both MM contained polymerized surfactant monomers terminated by chiral dipeptide headgroups. The study was undertaken to investigate why poly(SULV) is generally a better chiral selector compared to poly(SUVL) in electrokinetic chromatography separations. When comparing poly(SULV) to poly(SUVL), poly(SULV) had the more conformational flexible dipeptide headgroup and hydrogen bond analyses revealed that the poly(SULV) headgroup conformation allowed a larger number of intramolecular hydrogen bonds to form between monomer chains. In addition, a larger number of water molecules surrounded the chiral centers of the poly(SULV) molecular micelle. Poly(SULV) was also found to have a larger solvent accessible surface area (SASA) than poly(SUVL) and fluctuations in the poly(SULV) SASA during the MD simulation allowed dynamic monomer chain motions expected to be important in chiral recognition to be identified. Finally, approximately 50% of the Na+ counterions were found in the first three solvation shells surrounding both MM, with the remainder located in the bulk. Overall the MD simulations point to both greater headgroup flexibility and solvent and analyte access to the chiral centers of the dipeptide headgroup as factors contributing to the enhanced chiral selectivity observed with poly(SULV).

关键词： Chiral Recognition Polymeric Surfactant Molecular Modeling

Investigation of Chiral Molecular Micelles by NMR Spectroscopy and Molecular Dynamics Simulation

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Open Journal of Physical Chemistry 2012年第4期2卷 240-251页

作者： Kevin F. morris Eugene J. billiot Fereshteh H. billiot Kenny b. Lipkowitz William M. Southerland Yayin Fang Department of biochemistry and Molecular biology Howard University College of Medicine Howard University Washington DC USA Department of Chemistry Carthage College Kenosha USA Department of Physical and Environmental Sciences Texas A & M University Corpus Christi USA Office of Naval Research Arlington USA

NMR spectroscopy and Molecular Dynamics (MD) simulation analyses of the chiral molecular micelles poly-(Sodium Undecyl-(L,L)-Leucine-Valine) (poly-SULV) and poly-(Sodium Undecyl-(L,L)-Valine-Leucine) (poly-(SUVL)) are reported. both molecular micelles are used as chiral selectors in electrokinetic chromatography and each consists of covalently linked surfactant chains with chiral dipeptide headgroups. To provide experimental support for the structures from MD simulations, NOESY spectra were used to identify protons in close spatial proximity. Results from the NOESY analyses were then compared to radial distribution functions from MD simulations. In addition, the hydrodynamic radii of both molecular micelles were calculated from NMR-derived diffusion coefficients. Corresponding radii from the MD simulations were found to be in agreement with these experimental results. NMR diffusion experiments were also used to measure association constants for polar and non-polar binaphthyl analytes binding to both molecular micelles. Poly (SUVL) was found to bind the non-polar analyte enantiomers more strongly, while the more polar analyte enantiomers interacted more strongly with poly(SULV). MD simulations in turn showed that poly(SULV) had a more open structure that gave greater access for water molecules to the dipeptide headgroup region.

关键词： NOESY Chiral Recognition Polymeric Surfactant Molecular Modeling

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数字钢丝新技术

国外测井技术 2013年第4期33卷 68-75页

作者： Matthew billingham Vincent Chatelet morris Cox William b.Paulsen Nexen石油(美国)公司 ATP油气公司

长期以来修井技术一直依靠机械系统和液压系统传送井下工具，完成测量工作。因此，很多井下作业的结果（其深度通常是近似值）在很大程度上依赖于操作人员的经验和工具的有效设计。数字钢丝的开发成功有效克服了上述因素的限制。

关键词：钢丝新技术井下工具液压系统机械系统修井技术测量工作有效设计

Early infant male circumcision:Systematic review,risk-benefit analysis,and progress in policy

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世界临床儿科杂志 2017年第1期6卷 89-102页

作者： brian J morris Sean E Kennedy Alex D Wodak Adrian Mindel David Golovsky Leslie Schrieber Eugenie R Lumbers David J Handelsman John b Ziegler School of Medical Sciences and bosch Institute University of Sydney School of Women’s and Children’s Health University of New South Wales St Vincent’s Hospital and Kirby Institute for Infection and Immunity in Society University of New South Wales IVF Australia Department of Medicine Sydney Medical SchoolRoyal North Shore Hospital School of biomedical Sciences and Pharmacy Mothers and Babies Research CentreHunter Medical Research InstituteUniversity of Newcastle Department of Medicine and ANZAC Research Institute Concord Hospital Department of Immunology and Infectious Diseases Sydney Children’s Hospital

AIM To determine whether recent evidence-based United States polices on male circumcision(MC) apply to comparable Anglophone countries,Australia and New *** Articles in 2005 through 2015 were retrieved from PubM ed using the keyword "circumcision" together with 36 relevant subtopics.A further PubM ed search was performed for articles published in *** of the EMbASE and Cochrane databases did not yield additional citable *** were assessed for quality and those rated 2+ and above according to the Scottish Intercollegiate Grading System were studied *** most relevant andrepresentative of the topic were *** were examined to retrieve further key *** controlled trials,recent high quality systematic reviews or meta-analyses(level 1++ or 1+ evidence) were prioritized for inclusion.A risk-benefit analysis of articles rated for quality was *** efficiency and reliability,recent randomized controlled trials,metaanalyses,high quality systematic reviews and large welldesigned studies were used if *** searches were conducted for other relevant information,including policies and Australian data on claims under Medicare for *** Evidence-based policy statements by the American Academy of Pediatrics(AAP) and the Centers for Disease Control and Prevention(CDC) support infant and later age male circumcision(MC) as a desirable public health *** systematic review of relevant literature over the past decade yielded 140 journal articles that met our inclusion ***,these showed that early infant MC confers immediate and lifelong benefits by protecting against urinary tract infections having potential adverse long-term renal effects,phimosis that causes difficult and painful erections and "ballooning" during urination,inflammatory skin conditions,inferior penile hygiene,candidiasis,various sexually transmissible infections in both sexes,genital ulcers,and penil

关键词： Male circumcision Evidence-based policy Infants Adults Urinary tract infections Adverse events Sexually transmitted infections Genital cancers Riskbenefit analysis Cost-benefit

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中国室外地上木材腐朽危害分级

林业科学 2008年第9期44卷 113-117页

作者：蒋明亮王洁瑛吴讯英 morris Paul I 中国林业科学研究院木材工业研究所国家林业局木材科学与技术重点实验室北京100091 FPInnovations-Forintek Division Durability & ProtectionVancouverB C Canada V6T1 W5 国家气象局气象信息中心北京100081

以国内194个气象观测点月平均气温、月平均降水天数的数据为基础,计算出估测室外地上木材腐朽可能性的Scheffer气象指数,对室外地上木材腐朽危害等级进行划分并绘制出中国木材腐朽危害地图。南方大部分地区的Scheffer气象指数都高于70,... 详细信息

以国内194个气象观测点月平均气温、月平均降水天数的数据为基础,计算出估测室外地上木材腐朽可能性的Scheffer气象指数,对室外地上木材腐朽危害等级进行划分并绘制出中国木材腐朽危害地图。南方大部分地区的Scheffer气象指数都高于70,属于木材腐朽高危害地带,此地区包括云南南部,四川大部分地区和重庆市,湖南、湖北南部、安徽南部、江西和浙江南部,以及福建、广西、贵州、广东、海南、台湾。木材腐朽危害中等地带Scheffer气象指数在35～70之间,主要位于中国的中部,一个从西到东的狭长地带,包括西藏南部、云南北部、青海部分地区、甘肃部分地区、陕西部分地区、山西部分地区、河南部分地区、湖北大部、安徽大部、江苏以及上海市。另外,北京及其周围的一小块区域也属于木材腐朽危害中等地带。北方的大部分区域,从西到东,包括西藏大部、新疆大部、内蒙古、青海大部、甘肃大部、宁夏、陕西、山西大部、河北部分地区及河南小部,腐朽的危害指数低于35,属于低危害地带。本腐朽地图为中国不同地区室外地上木材的合理使用及防护提供了参考依据。

关键词：腐朽危害等级 Scheffer气象指数室外地上用木材腐朽危害地图中国

Puroindolineb位点近等基因系对小麦面粉及面包和馒头品质的影响

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作物学报 2010年第2期36卷 261-266页

作者：马冬云张艳夏先春 Craig F morris 何中虎中国农业科学院作物科学研究所国家小麦改良中心北京100081 河南农业大学国家小麦工程技术研究中心河南郑州450002 USDA-ARS Western Wheat Quality Laboratory P.O.Box 646394PullmanWA 99164-6394USA 国际玉米小麦改良中心中国办事处北京100081

明确不同硬度等位基因与加工品质的关系对小麦品质改良具有重要意义。本文以7个Puroindoline b位点近等基因系为材料,研究了不同硬度等位基因对小麦面粉及面包和馒头品质的影响。结果表明,Pina-D1b/Pinb-D1a基因型的籽粒硬度值、蛋白质... 详细信息

明确不同硬度等位基因与加工品质的关系对小麦品质改良具有重要意义。本文以7个Puroindoline b位点近等基因系为材料,研究了不同硬度等位基因对小麦面粉及面包和馒头品质的影响。结果表明,Pina-D1b/Pinb-D1a基因型的籽粒硬度值、蛋白质含量以及破损淀粉含量较高;而Pina-D1a/Pinb-D1d基因型的出粉率、面粉亮度较高,具有较好的磨粉品质。和面仪参数中的峰高、峰宽和8min尾高均以Pina-D1b/Pinb-D1a基因型数值最高,Pina-D1a/Pinb-D1d基因型最低,且两者之间的差异均达到显著水平;Pina-D1b/Pinb-D1a基因型的衰落角最小。Pina-D1a/Pinb-D1c和Pina-D1a/Pinb-D1d基因型具有较高馒头色泽和张弛性评分,较好的馒头制作品质;Pina-D1a/Pinb-D1e和Pina-D1a/Pinb-D1g基因型次之。Pina-D1a/Pinb-D1f基因型的面包总评分略优于其他基因型。

关键词：普通小麦 Puroindoline基因近等基因系面粉品质馒头品质面包品质

Gastric cancer in women: A regional health-center seven year retrospective study

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World Journal of Gastroenterology 2015年第25期21卷 7805-7813页

作者： Kunal Suryawala Demiana Soliman Monica Mutyala Shaheen Nageeb Moheb boktor Abhishek Seth Avinash Aravantagi Ankur Sheth James morris Paul Jordan Kenneth Manas Urska Cvek Marjan Trutschl Felix becker Jonathan Alexander Department of Gastroenterology and Hepatology Louisiana State University Health Sciences Center Department of Molecular and Cellular Physiology Louisiana State University Health Sciences Center Department of Computer Science LSU Shreveport and Center for Molecular and Tumor Virology Louisiana State University Health Sciences Center Department of General and Visceral Surgery University Hospital Muenster

AIM: To investigate whether regional geography influences ethnic and gender trends for the development of gastric cancer(GC).METHODS: This retrospective analysis of the INVISION patient database at Louisiana State University Health Sciences Center-Shreveport(LSUHSC-S), a southern United States regional hospital, was performed from 2005-2011. Using the international statistical classification of diseases 9(ICD-9), inpatient, day surgery outpatient, and emergency outpatient diagnosis codes entered into medical records were used to identify GC patients. For each study year, the patients were evaluated for age, ethnicity, and gender, and each patient was counted only once throughout the study. Subsequent patient encounters were counted as visits and separated by inpatient and clinic visits. Complex or severe disease may require more frequent and intensive clinical management; therefore, we evaluated annual clinic visits as "surrogate markers" of disease severity. Finally, we studied the primary diagnosis for Helicobacter pylori(H. pylori) infection(ICD-9 code 41.86) as an additional factor that might increase the risk of ***: A total of 285 patients were diagnosed with GC at LSUHSC-S between 2005 and 2011. African Americans(181 patients, 89 males and 92 females, 63.5% of total patients) had significantly higher frequencies of GC diagnosis compared with non-Hispanic whites(104 patients, 54 males and 50 females, 36.5% of total patients), at a ratio of 1.74(P = 0.002). Within each ethnic group, men and women were diagnosed at approximately equal annual rates. Our findings differed significantly from United States national trends, which found that African American females and white females had lower risks for GC than their corresponding male counterparts. The United States national trend between 2005 and 2011 showed that African Americans males had a higher incidence of GC, with an annual mean(per 100000) of 16.31 ± 0.76 compared with white males(9 ± 0.1, P < 0.001),

关键词： Gender Helicobacter pylori Ethnicity Riskfactors Health disparities

ADAS——由微型计算机控制的一种通用大气数据获取系统

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气象科技 1984年第4期 86-88页

作者： David b.Call Alvin L.morris 张菊生美国大气仪器研究公司美国环境分析公司

本文描述用微型计算机控制的一种新的数据获取系统,它可以作为一些气象观测系统如自动气象站、用作二级标准的气象传感器以及系留气球或自由气球探测系统的核心设备。一、概述大气数据获取系统(ADAS)是一种小型的通用系统,它由 Z-80微... 详细信息

本文描述用微型计算机控制的一种新的数据获取系统,它可以作为一些气象观测系统如自动气象站、用作二级标准的气象传感器以及系留气球或自由气球探测系统的核心设备。一、概述大气数据获取系统(ADAS)是一种小型的通用系统,它由 Z-80微处理机、可编程序的频率计数器、可选择的超高速数理芯片、几块 ROM 片、纸带读出器、发光二极管数字显示器、键盘、几个输入/输出端口、经纬仪接口组成,还带有供比较用的 HP-97计算器和盒式磁带记录器。与 ADAS 配合使用的各输入装置必须提供音频信号,此信号的频率是所测变量的测值的函数,由可编程序的频率计数器测出。参考频率和各种校准系数,通过键盘或纸带输入,然后由微型计算机计算所测气象变量的取样值并进而算出各种导出数

关键词： ADAS 经纬仪音频测绘仪器无线电探空仪轴角编码器微型计算机控制数据收集数据获取

Pelage color of red bats Lasiurus borealis varies with body size:An image analysis of museum specimens

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Current Zoology 2010年第4期56卷 401-405页

作者： Andrew K.DAVIS Steven b.CASTLEbERRY D.b. Warnell School of Forestry and Natural Resources The University of Georgia

Mammalian pelage color can vary among individuals of many species, although this intraspecific variation is oftenoverlooked by researchers, perhaps because of its sometimes subtle nature and difficulty in assessing it quantitatively. Thus, suchvariation is rarely studied in mammals, and this is especially true within the order Chiroptera, where there has been very little empiricalresearch. We examined museum specimens of red bats (Lasiurus borealis, family Vespertilionidae) from Georgia, USA, todetermine the extent of sexual dimorphism in pelage color and to explore possible associations between body size and pelagecolor. We photographed 54 specimens under uniform lighting, and used an image analysis program to measure pelage hue on theuropatagium region, which is fully furred in members of the genus Lasiurus. Statistical analyses of pelage hue scores showedmales had significantly redder pelage than females when considered alone, but when examined together with effects of body sizeand collection year, sex was not significant, and collection year and body size were. More recent specimens tended to be less redthan older specimens, which might indicate a wearing of the buffy tips of hairs from older specimens, and smaller bats of bothsexes tended to be more red. These interesting findings are encouraging and we suggest that future explorations into intraspecificvariation in pelage color of bats using this or similar approaches are warranted to clarify the significance of the patterns. Thisstudy also demonstrated that care must be taken in analyses of mammalian pelage color from older museum skins, or at least thatresearchers must take into account the age of the specimens .

关键词： Pelage color Sexual dimorphism Red bats Lasiurus borealis Image analysis