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Recent advances and remaining gaps in our knowledge of associations between gut microbiota and human health

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World Journal of Gastroenterology 2009年第1期15卷 81-85页

作者： volker Mai Peter V Draganov Department of Gastroenterology Hepatology and Nutrition University of Florida1600 SW Archer Rd Room HD 602 PO Box 100214 Gainesville Florida 32610 United States

The complex gut microbial flora harbored by individuals(microbiota) has long been proposed to contribute tointestinal health as well as disease. Pre-and probioticproducts aimed at improving health by modifyingmicrobiota composition have already become widelyavailable and acceptance of these products appearsto be on the rise. However, although required forthe development of effective microbiota basedinterventions, our basic understanding of microbiotavariation on a population level and its dynamics withinindividuals is still rudimentary. Powerful new parallelsequence technologies combined with other efficientmolecular microbiota analysis methods now allow forcomprehensive analysis of microbiota composition inlarge human populations. Recent fi ndings in the fi eldstrongly suggest that microbiota contributes to thedevelopment of obesity, atopic diseases, inflammatorybowel diseases and intestinal cancers. Through theongoing National Institutes of Health Roadmap 'HumanMicrobiome Project' and similar projects in other partsof the world, a large coordinated effort is currentlyunderway to study how microbiota can impact humanhealth. Translating findings from these studies intoeffective interventions that can improve health,possibly personalized based on an individuals existingmicrobiota, will be the task for the next decade(s).

关键词： Microbiota Intestinal microbial flora Probiotic Gut Intestine

State of the Art Treatment of Non-Ferrous Castings 3-in-l Heat Treatment Systems Combine Foundry Processes

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材料热处理学报 2004年第5期25卷 552-554页

作者： volker R. Knobloch CEC - Consolidated Engineering Co. Inc.

The interior of a high-pressure die-casting is of an unsatisfactory quality. Engine blocks made with this die casting process show lower specific engine performance. Pressure die-casting can hardly be heat treated for obvious reasons. PSM (Precision Sand Molds) process uses sand and organic binder to generate a mold and even allows the manufacturing of complex diesel engine blocks in aluminum alloys. Combined technologies are available for semi-permanent mold castings with cores and castings made in Precision Sand Molds with organic binders. Castings are placed into the special heat treatment furnace immediately after pouring without the operations in stand alone machinery. This patented Sand Lion 3- in-1 technology processes hot castings and carries out three (3) foundry processes simultaneously in one (1) automated machine: 1) De-coring and sand removal; 2) Thermal sand reclamation; 3) Solution heat treatment of castings. The combination of several main casting processes is reflected in significant reductions of energy consumption, of production costs, and improving the quality of the castings. Audits in foundries using the 3-in-l process showed an average reduction in production costs of more than 30%.

关键词：沙模固溶热处理集成铸造流化床

Regenerative capacity of Müller cells and their modulation as a tool to treat retinal degenerations

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Neural Regeneration Research 2023年第1期18卷 139-140页

作者： Federica M.Conedera volker Enzmann Advanced Microscopy Program Center for Systems BiologyMassachusetts General HospitalBostonMAUSA Wellman Center for Photomedicine Massachusetts General HospitalBostonMAUSA(Conedera FM)Department of OphthalmologyUniversity HospitalUniversity of BernBernSwitzerland Department of BioMedical Research University of BernBernSwitzerland

Vision is one of our most precious senses,and its impairment has a high socio-economic *** the industrialized world,degenerative diseases of the retina lead to vision loss,particularly among the *** degenerations include,for instance,retinitis pigmentosa,age-related macular degeneration,and diabetic *** treatments are evolving to manage late-stage symptoms of retinal degenerations,no effective therapies to recover vision loss *** degeneration often involves loss or damage to specialized neural cells,such as photoreceptors,and their death stimulates the activation and proliferation of Müller cells(Salman et al.,2021).

关键词： degeneration diseases impairment

Prevalence of H pylori associated 'high risk gastritis' for development of gastric cancer in patients with normal endoscopic findings

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World Journal of Gastroenterology 2006年第34期12卷 5509-5512页

作者： Andreas Leodolter Matthias P Ebert Ulrich Peitz Kathlen Wolle Stefan Kahl Michael vieth Peter Malfertheiner Department of Gastroenterology and Hepatology Otto-von-Guericke University Magdeburg Leipziger Street 44 Magdeburg 39120 Germany Institute of Pathology Otto-von-Guericke University Magdeburg Leipziger Street 44 Magdeburg 39120 Germany

AIM： To investigate the prevalence of H pylori associated corpus-predominant gastritis （CPG） or pangastritis, severe atrophy, and intestinal metaplasia （IM） in patients without any significant abnormal findings during upper- GI endoscopy. METHODS： Gastric biopsies from 3548 patients were obtained during upper GI-endoscopy in a 4-year period. Two biopsies from antrum and corpus were histologically assessed according to the updated Sydney-System. Eight hundred and forty-five patients （mean age 54.8 ± 2.8 years） with H pylori infection and no peptic ulcer or abnormal gross findings in the stomach were identified and analyzed according to gastritis phenotypes using different scodng systems. RESULTS： The prevalence of severe H pylori associated changes like pangastritis, CPG, IN, and severe atrophy increased with age, reaching a level of 20% in patients of the age group over 45 years. No differences in frequencies between genders were observed. The prevalence of IM had the highest increase, being 4-fold higher at the age of 65 years versus in individuals less than 45 years. CONCLUSION： The prevalence of gastritis featuring at risk for cancer development increases with age. These findings reinforce the necessity for the histological assessment, even in subjects with normal endoscopic appearance. The age-dependent increase in prevalence of severe histopathological changes in gastric mucosa, however, does not allow estimating the individual risk for gastric cancer development-only a proper follow-up can provide this information.

关键词： H pylori Gastric cancer Gastritis

Current clinical approach to achalasia

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World Journal of Gastroenterology 2009年第32期15卷 3969-3975页

作者： Alexander J Eckardt volker F Eckardt Central Interdisciplinary Endoscopy Unit Department of Gastroenterology and HepatologyCharité University Hospitals BerlinCampus VirchowD-13353 BerlinGermany Department of Gastroenterology Deutsche Klinik für DiagnostikD-65191 WiesbadenGermany

Idiopathic achalasia is a rare primary motility disorder of the esophagus. The classical features are incomplete relaxation of a frequently hypertensive lower esophageal sphincter (LES) and a lack of peristalsis in the tubular esophagus. These motor abnormalities lead to dysphagia, stasis, regurgitation, weight loss, or secondary respiratory complications. Although major strides have been made in understanding the pathogenesis of this rare disorder, including a probable autoimmune mediated destruction of inhibitory neurons in response to an unknown insult in genetically susceptible individuals, a definite trigger has not been identified. The diagnosis of achalasia is suggested by clinical features and conf irmed by further diagnostic tests, such as esophagogastroduodenoscopy (EGD), manometry or barium swallow. These studies are not only used to exclude pseudoachalasia, but also might help to categorize the disease by severity or clinical subtype. Recent advances in diagnostic methods, including high resolution manometry (HRM), might allow prediction of treatment responses. The primary treatments for achieving long-term symptom relief are surgery and endoscopic methods. Although limited high-quality data exist, it appears that laparoscopic Heller myotomy with partial fundoplication is superior to endoscopic methods in achieving long-term relief of symptoms in the majority of patients. However, the current clinical approach to achalasia will depend not only on patients' characteristics and clinical subtypes of the disease, but also on local expertise and patient preferences.

关键词： Achalasia Esophageal motility disorder Dysphagia Esophagus Lower esophageal sphincter Pneumatic dilation Botulinum toxin Heller myotomy

Challenges in microRNAs’ targetome prediction and validation

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Neural Regeneration Research 2019年第10期14卷 1672-1677页

作者： Jesus Eduardo Rojo Arias volker Busskamp Center for Regenerative Therapies (CRTD) Technische Universit?t Dresden

MicroRNAs(miRNAs)are small RNA molecules with important roles in post-transcriptional regulation of gene *** recent years,the predicted number of miRNAs has skyrocketed,largely as a consequence of high-throughput sequencing technologies becoming *** dramatic increase in miRNA candidates poses multiple challenges in terms of data deposition,curation,and *** multiple databases containing miRNA annotations and targets have been developed,ensuring data quality by validating miRNA-target interactions requires the efforts of the research *** order to generate databases containing biologically active miRNAs,it is imperative to overcome a multitude of hurdles,including restricted miRNA expression patterns,distinct miRNA biogenesis machineries,and divergent miRNA-mRNA interaction *** the present review,we discuss recent advances and limitations in miRNA prediction,identification,and ***,we focus on the most enriched neuronal miRNA,miR-124,and its gene regulatory network in human neurons,which has been revealed using a combined computational and experimental approach.

关键词： miRNAs miRNA regulation miR-124 wTO analysis miRNA biogenesis miRNA prediction miRNA identification miRNA validation

Effect of Continuous Phase Viscosity on Membrane Emulsification

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Chinese Journal of Chemical Engineering 2000年第2期8卷 108-112页

作者：王志王世昌 volker Schroeder Helmar Schubert Institute of Food Process Engineering Karlsruhe UniversityD-76128 KarlsruheGermany

Oil-in-water(o/w) emulsions were produced with a membrane emulsification system. The effect of the continuous phase viscosity on the emulsification was studied. The theoretical analyses show that the continuous phase viscosity influences not only the flow field of the continuous phase but also the interfacial tension. The droplet size distribution and disperse phase flux for different continuous phase viscosity were investigated experimentally at constant wall shear stress and constant volume flow rate of the continuous phase respectively.

关键词： membrane emulsification viscosity continuous phase

rCOS： a formal model-driven engineering method for component-based software

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Frontiers of Computer Science 2012年第1期6卷 17-39页

作者： Wei KE Xiaoshan LI Zhiming LIU volker STOLZ School of Computer Science and Engineering Beihang University Beijing 100191 China Faculty of Science and Technology University of Macao Macao China UNU-IIST Macao China Department of Informatics University of Oslo Oslo 0316 Norway Macao Polytechnic Institute Macao China

Model-driven architecture （MDA） has become a main stream technology for software-intensive system design. The main engineering principle behind it is that the inherent complexity of software development can only be mastered by building, analyzing and manipulating system models. MDA also deals with system complexity by provid- ing component-based design techniques, allowing indepen- dent component design, implementation and deployment, and then system integration and reconfiguration based on com- ponent interfaces. The model of a system in any stage is an integration of models of different viewpoints. Therefore, for a model-driven method to be applied effectively, it must pro- vide a body of techniques and an integrated suite of tools for model construction, validation, and transformation. This requires a number of modeling notations for the specifica- tion of different concerns and viewpoints of the system. These notations should have formally defined syntaxes and a unified theory of semantics. The underlying theory of the method is needed to underpin the development of tools and correct use of tools in software development, as well as to formally ver- ify and reason about properties of systems in mission-critical applications. The modeling notations, techniques, and tools must be designed so that they can be used seamlessly in sup- porting development activities and documentation of artifactsin software design processes. This article presents such a method, called the rCOS, focusing on the models of a system at different stages in a software development process, their se- mantic integration, and how they are constructed, analyzed, transformed, validated, and verified.

关键词： component-based design models model trans-formations verification tool support

Evaluation of Turbulence Models in Predicting Hypersonic and Subsonic Base Flows Using Grid Adaptation Techniques

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Chinese Journal of Aeronautics 2012年第3期25卷 325-334页

作者： YOU Yancheng BUANGA Bjorn HANNEMANN volker LUDEKE Heinrich Institute of Aerodynamics and Flow Technology German Aerospace Center (DLR) Braunschweig 38108 Germam Institute of Aerodynamics and Flow Technology German Aerospace Center (DLR) Gottingen 37073 Germany Department of Aeronautics Xiamen University Xiamen 361005 China

The flows behind the base of a generic rocket, at both hypersonic and subsonic flow conditions, are numerically studied. The main concerns are addressed to the evaluation of turbulence models and the using of grid adaptation techniques. The investigation focuses on two configurations, related to hypersonic and subsonic experiments. The applicability tests of different turbu- lence models are conducted on the level of two-equation models calculating the steady state solution of the Reynolds-averaged Navier-Stokes（RANS） equations. All used models, the original Wilcox k-co, the Menter shear-stress transport （SST） and the ex- plicit algebraic Reynolds stress model（EARSM） formulation, predict an asymmetric base flow in both cases caused by the support of the models. A comparison with preliminary experimental results indicates a preference for the SST and EARSM results over the results from the older k-co model. Sensitivity studies show no significant influence of the grid topology or the location of the laminar to turbulent transition on the base flow field, but a strong influence of even small angles of attack is reported from the related experiments.

关键词： base flows turbulence models steady calculation grid adaptation numerical simulation