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Effect of medical and surgical treatment of barrett's metaplasia

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World Journal of Gastroenterology 2010年第30期16卷 3773-3779页

作者： Eelco b Wassenaar brant k Oelschlager Center for Videoendoscopic Surgery Department of SurgeryUniversity of WashingtonSeattleWA 98195United States

barrett’s esophagus (bE) is a change in the esophageal mucosa as a result of long-standing gastroesophageal reflux disease. The importance of bE is that it is the main risk factor for the development of esophageal adenocarcinoma, whose incidence is currently growing faster than any other cancer in the Western world. The aim of this review was to compare the common treatment modalities of bE, with the focus on proton pump inhibitors and operative fundoplication. We performed a literature search on medical and surgical treatment of bE to determine eligible studies for this review. Studies on medical and surgical treatment of bE are discussed with regard to treatment effect on progression and regression of disease. Although there is some evidence for control of reflux with either medical or surgical therapy, there is no def initive evidence that either treatment modality decreases the risk of progression to dysplasia or cancer. Even though there is a trend toward antireflux surgery being superior, there are no def initive studies to prove this.

关键词： barrett’s esophagus Intestinal metaplasia Proton pump inhibitors Nissen fundoplication Esophageal adenocarcinoma Gastroesophageal reflux

A model for expansion ratio in liquid-solid fluidized beds

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Particuology 2013年第6期11卷 789-792页

作者： Alok Tripathy A.k.Sahu S.k.biswal b.k.Mishra Council of Scientific and Industrial Research Institute of Minerals and Materials Technology

Liquid-solid fluidized beds are used in mineral processing industries to separate particles based on parti- cle size, density, and shape. Understanding the expanded fluidized bed is vital for accurately assessing its performance. Expansion characteristics of the fluidized bed were studied by performing several experi- ments with iron ore, chromite, quartz, and coal samples. Using water as liquid medium, experiments were conducted to study the effects of particle size, particle density, and superficial velocity on fluidized bed expansion. The experimental data were utilized to develop an empirical mathematical model based on dimensional analysis to estimate the expansion ratio of the fluidized bed in terms of particle character- istics, operating and design parameters. The predicted expansion ratio obtained from the mathematical model is in good agreement with the experimental data.

关键词： Fluidization bed expansion Mathematical modelling Dimensional analysis Particle processing Void fraction

Enhanced green emission from La＿(0.4)F＿3:Ce＿(0.45),Tb＿(0.15)/TiO＿2 core/shell structure

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Journal of Rare Earths 2015年第1期33卷 20-26页

作者： T.k.Srinivasan b.S.Panigrahi N.Suriyamurthy P.k.Parida b.Venkatraman Indira Gandhi Centre for Atomic Research Kalpakkam–603102 India

Nano sized La0.4F3：Ce0.45,Tb0.15（core）, La0.4F3：Ce0.45,Tb0.15（Ti O2）（core） shell, La0.55F：Ce0.45, and La0.85F3：Tb0.15 particles were synthesized by adopting co-precipitation technique in acidic environment and coated with Ti O2 to form a core-shell structure by adopting a mechanical dispersion method at room temperature. The synthesized materials were characterized using X-ray diffraction（XRD）, transmission electron microscopy（TEM）, Fourier transform infrared spectroscopy（FTIR）, ultraviolet-visible spectroscopy（UV-Vis） absorption, photoluminescence and lifetime spectroscopy. The crystal structure of La0.4F3：Ce0.45,Tb0.15 remained the same as La F3 after being doped with Ce and Tb ions but with a slight decrease in the lattice parameter. TEM image confirmed the formation of a core-shell structure. The La0.4F3：Ce0.45,Tb0.15/Ti O2 exhibited Tb3＋ fluorescence enhancement by a factor of 1.76. Scintillation from the synthesized materials was also observed under X-ray excitation.

关键词： core-shell cerium terbium luminescence lanthanum fluoride scintillation rare earths

Flow, thermal, and vibration analysis using three dimensional finite element analysis for a flux reversal generator

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Frontiers in Energy 2016年第4期10卷 424-440页

作者： b. VIDHYA k. N. SRINIVAS 1. Department of Electrical and Electronics Engineering B. S. Abdur Rahman University Chennai 600048 India

This paper presents the simulation of major mechanical properties of a flux reversal generator （FRG） viz., computational fluid dynamic （CFD）, thermal, and vibration. A three-dimensional finite element analysis （FEA） based CFD technique for finding the spread of pressure and air velocity in air regions of the FRG is described. The results of CFD are mainly obtained to fine tune the thermal analysis. Thus, in this focus, a flow analysis assisted thermal analysis is presented to predict the steady state temperature distribution inside FRG. The heat transfer coefficient of all the heat producing inner walls of the machine are evaluated from CFD analysis, which forms the main factor for the prediction of accurate heat distribution. The vibration analysis is illustrated. Major vibration sources such as mechanical, magnetic and applied loads are covered elaborately which consists of a 3D modal analysis to find the natural frequency ofFRG, a 3D static stress analysis to predict the deformation of the stator, rotor and shaft for different speeds, and an unbalanced rotor harmonic analysis to find eccentricity of rotor to make sure that the vibration of the rotor is within the acceptable limits. Harmonic analysis such as sine sweep analysis to identify the range of speeds causing high vibrations and steady state vibration at a mode frequency of 1500 Hz is presented. The vibration analysis investi- gates the vibration of the FRG as a whole, which forms the contribution of this paper in the FRG literature.

关键词： flux reversal generator air velocity computa-tion fluid dynamics thermal analysis vibration analysis,finite element analysis

The emerging roles of microRNAs in the molecular responses of metabolic rate depression

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Journal of Molecular Cell biology 2011年第3期3卷 167-175页

作者： kyle k.biggar kenneth b.Storey Institute of biochemistry and Department of biology Carleton University1125 Colonel By DriveOttawaONCanada K1S 5B6

Metabolic rate depression is an important survival strategy for many animal species and a common element of hibernation,torpor,estivation,anoxia and *** of the molecular mechanisms that regulate reversible transitions to and from hypometabolic states have identified principles of regulatory *** control mechanisms are conserved among biologically diverse organisms and include the coordinated reduction of specific groups of key regulatory enzymes or proteins in the cell,a process likely driven by microRNA target repression/*** present review focuses on a growing area of research in hypometabolism and mechanisms involving the rapid and reversible control of translation facilitated by *** analysis draws primarily from current research on three animal models:hibernating mammals,anoxic turtles and freeze-tolerant frogs(with selected examples from multiple other sources).Here,we demonstrate a link between metabolic rate depression,a well-documented response to periods of environmental stress,and microRNA ***-based expression profiles and PCR-driven studies have revealed that specific microRNAs are induced in response to environmental *** members of this group decrease pro-apoptotic signaling,reduce muscle wasting and reduce protein translation,whereas other members contribute to cell cycle arrest and mitogen-activated protein kinase *** of the same microRNAs are frequently deregulated in numerous disease pathologies and,hence,the hypometabolism model could provide a novel approach for the treatment of stroke and heart attack in humans.

关键词： microRNA metabolism metabolic rate depression protein translation muscle atrophy cell cycle apoptosis

Slurry wear characteristics of zinc-based alloys： Effects of sand content of slurry, silicon addition to alloy system and traversal distance

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中国有色金属学会会刊：英文版 2009年第2期19卷 277-286页

作者： b.k. PRASAD, O.P. MODI Advanced Materials and Processes Research Institute （CSIR） Bhopal-462026 India

这调查处理在泥浆上与标本和泥浆作文以及遍历距离的效果相关的观察穿基于锌的合金的反应。合金的作文被把 4% 硅加到它改变。泥浆作文通过在被推迟在的 060% 的范围改变沙粒子的集中被改变(液体) 电解质。电解质包含了集中的硫的酸在水... 详细信息

这调查处理在泥浆上与标本和泥浆作文以及遍历距离的效果相关的观察穿基于锌的合金的反应。合金的作文被把 4% 硅加到它改变。泥浆作文通过在被推迟在的 060% 的范围改变沙粒子的集中被改变(液体) 电解质。电解质包含了集中的硫的酸在水的 10 L 溶解了的 4 g 钠氯化物和 5 mL。泥浆穿测试在 15500 km 的遍历距离范围上以 7.02 m/s 的速度被进行。wear 率开始与遍历距离增加了，达到了最大值并且不管标本和测试环境，此后减少了。然而， wear 率山峰比液体唯一的媒介在加沙环境的液体是不太突出的。进一步，在液体唯一的媒介的 wear 率山峰在包含泥浆的沙比那座出现在更短的遍历距离。到电解质的沙粒子的增加把样品的 wear 率归结为取决于泥浆的沙集中的 5%15% 。而且，中介(40%) 沙内容导致了最大值穿率什么时候与相比在加沙媒介的液体。然而，这最大值是静止的不到在里面液体唯一的媒介。包含更高受不了的合金的硅比当在液体唯一的媒介测试了时，免费合金取样的硅穿率。相反，而混合回答在包含 60% 沙的泥浆被注意，趋势加 20% 和 40% 沙环境在液体逆行。在后者盒子中，当一个相反的趋势在更长的遍历距离被观察时，硅的存在开始证明有害。样品的 wear 反应在试验性的条件的一个给定的集合以他们象硅和占优势的材料移动机制一样的 microconstituents 的特定的特征被讨论。合金的观察行为也通过他们的影响表面和表面下的区域的特征进一步被证实。

关键词：锌基合金磨损特性硅合金泥浆加砂远程系统渣浆泵测试环境

Investigation into machining performance of microstructurally engineered in-situ particle reinforced magnesium matrix composite

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Journal of Magnesium and Alloys 2023年第3期11卷 916-935页

作者： S.k.Sahoo b.N.Sahoo S.k.Panigrahi Department of Mechanical Engineering Indian Institute of Technology MadrasChennai 600036India Applied Magnesium Research Group Center of Excellence in Materials and Manufacturing for Futuristic MobilityIndian Institute of Technology MadrasChennai 600036India Department of Mechanical Engineering Sardar Vallabhbhai National Institute of TechnologySurat 395007India

Magnesium and magnesium in-situ composites have significant potential in the application of design and manufacturing for automotive and aerospace industries because of their high specific strength and reduced fuel *** there are many challenges for machining of Mg based alloys and composites because of the high tendency of fire and *** challenges can be minimized through microstructural *** this present study,the machining performances of AZ91 Mg alloy and in-situ hybrid TiC+Tib_(2)reinforced AZ91 metal matrix composite was *** effectβ-Mg_(17)Al_(12)phases and grain refinement with and without in-situ particles on machinability were studied through microstructural engineering via aging and friction stir *** end milling operation was carried out at different cutting speeds ranging from 25 mm/min to 90 mm/min under dry environment by using an AlTiN-coated tungsten carbide *** optimum cutting speed for machining was found to be 75 mm/min based on the surface roughness values of all conditioned *** base material with dendritic microstructure was found to have poor machinability in terms of inadequate surface finish and edge-burrs *** combined effect of in-situ TiC+Tib_(2)particles addition and grain refinement enhanced the machining performance of the material with superior surface finish,negligible edge-burr formation and better tool wear *** influence of in-situ TiC+Tib_(2)particles,β-Mg_(17)Al_(12)phases and grain refinement on machining characteristics are explained based on the tool wear mechanisms,chip behavior and machining induced affected zone.

关键词： Magnesium In-situ composite End-milling Tool wear Chip morphology

CFD modeling of pressure drop and drag coefficient in fixed beds:Wall effects

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Particuology 2010年第1期8卷 37-43页

作者： Rupesh k.Reddy Jyeshtharaj b.Joshi Department of Chemical Engineering Institute of Chemical TechnologyMatungaMumabiIndia

Simulations of fixed beds having column to particle diameter ratio （D/dp） of 3, 5 and 10 were performed in the creeping, transition and turbulent flow regimes, where Reynolds number （dpVLρL/μL） was varied from 0.1 to 10,000. The deviations from Ergun＇s equation due to the wall effects, which are important in D/dp 〈 15 beds were well explained by the CFD simulations. Thus, an increase in the pressure drop was observed due to the wall friction in the creeping flow, whereas, in turbulent regime a decrease in the pressure drop was observed due to the channeling near the wall. It was observed that, with an increase in the D/dp ratio, the effect of wall on drag coefficient decreases and drag coefficient nearly approaches to Ergun＇s equation. The predicted drag coefficient values were in agreement with the experimental results reported in the literature, in creeping flow regime, whereas in turbulent flow the difference was within 10-15%.

关键词： Computational fluid dynamics Fixed bed Wall effects Pressure drop Drag coefficient

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新疆石油地质 2001年第2期22卷 172-176页

作者： ЕpШObC.b. kaэаненkoвb.A. kароroдиню.H. ИHCTHTYTreoпrиннефтннraaaCибнpckoroOтдениБPoccийckoйAkaдemиинayk HoBocибHpck630090PoccиБ