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Discharge-Stage Relationship on Urban Streams evaluated at USGS Gauging Stations,***,Missouri

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Journal of earth Science 2020年第6期31卷 1133-1141页

作者： Robert e.Criss David l.Nelson Department of earth and Planetary Sciences Washington UniversitySt.Louis MO 63130USA Columbia Cir Pasadena CA 91105USA

extensive USGS data tables and detailed,1 m2 li DAR surveys are used to determine the optimal power n that relates discharge(Q)to stage(h*)above channel bottom(ho)at 39 gauging stations on small streams in the ***,Missouri area,all of which have catchments of 0.6 to 220 *** different methodologies are employed to determine both n and ho:(1)optimizing linearity in a plot of Q1/n *** stage(hl)using USGS field measurements at each site;(2)optimizing linearity in a plot of Q1/n *** using USGS rating tables at each site;(3)a mathematical inverse method applied to the same USGS rating tables;(4)use of li DAR data on channel geometry to determine the power dependences of channel area A and hydraulic radius H on h*,combined with the Manning and rational equations to predict *** these methods,only methods 2 and 3 compare favorably,and these values compare poorly with Method 1 based on field data,and with method 4 based on theoretical and empirical *** Method 4 is predictive,it provides a useful alternative to methods 1–3 that are based on USGS field measurements,which are heavily weighted toward low *** conclude that the apparent values of n in the USGS rating tables are systematically too low for small streams.

关键词： stream gauging li DAR topography urban flooding discharge hydrology

In vivo mouse models to study bile acid synthesis and signaling

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Hepatobiliary & Pancreatic Diseases International 2023年第5期22卷 466-473页

作者： Anisha Bhattacharya Rulaiha e Taylor Grace l Guo Department of Pharmacology and Toxicology Ernest Mario School of PharmacyRutgersThe State University of New JerseyPiscatawayNew JerseyUSA Rutgers Center for lipid Research RutgersThe State University of New JerseyNew BrunswickNew JerseyUSA environmental and Occupational Health Sciences Institute RutgersThe State University of New JerseyPiscatawayNew JerseyUSA VA New Jersey Health Care System Veterans Administration Medical CenterEast OrangeNew JerseyUSA

The synthesis of bile acids(BAs)is carried out by complex pathways characterized by sequential chemical reactions in the liver through various cytochromes P450(CYP)and other *** the integrity of these pathways is crucial for normal physiological function in mammals,encompassing hepatic and neurological *** on the deficiencies in BA synthesis genes offers valuable insights into the significance of BAs in modulating farnesoid X receptor(FXR)signaling and metabolic *** creating mouse knockout(KO)models,researchers can manipulate deficiencies in genes involved in BA synthesis,which can be used to study human diseases with BA *** KO mouse models allow for a more profound understanding of the functions and regulations of genes responsible for BA ***,KO mouse models shed light on the distinct characteristics of individual BA and their roles in nuclear receptor ***,alterations of BA synthesis genes in mouse models have distinct differences when compared to human diseases caused by the same BA synthesis gene *** review summarizes several mouse KO models used to study BA synthesis and related human diseases,including mice deficient in Cyp7a1,Cyp27a1,Cyp7a1/Cyp27a1,Cyp8b1,Cyp7b1,Cyp2c70,Cyp2a12,and Cyp2c70/Cyp2a12,as well as germ-free mice.

关键词： Bile acid Species difference Farnesoid X receptor liver diseases

Pore structure of cementitious material enhanced by graphitic nanomaterial： a critical review

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Frontiers of Structural and Civil engineering 2018年第1期12卷 137-147页

作者： S.A. GHAHARI e. GHAFARI l. ASSI Department of Civil engineering Purdue University USA Department of Civil and environmental engineering University of South Carolina USA

Carbon nano tubes （CNT） has been introduced as an efficient nanomaterial in order to improve the mechanical and durability properties of concrete. The effect of CNT on the microstructures of cementitious materials has been widely reported. This paper combines a critical review on the effect of CNT on the pore and microstructure of cement composite with a discussion on the porosity measurement of pastes containing CNT using mercury intrusion porosimetry techniques （MIP）. It was found that, surface treatment by H2SO4 and HNO3 solution forms carboxyl acid groups on CNTs＇ surfaces that lead to the improvement of reinforcement. In this scope, this review paper involves analyzing the effect of CNT on the microstructure and the pore structure of cementitious materials. The existing methods of measuring the porosity of cementitious material are reviewed, in particular, the contact angle measurement is discussed in detail in which the most effective parameters and possible errors of calculation is presented.

关键词： carbon nano tubes microstructure porosity mercury intrusion porosimetry cement composite

On correction of model of stabilization of distribution of concentration of radiation defects in a multilayer structure with account experiment data

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Journal of Semiconductors 2018年第5期39卷 6-15页

作者： e.l.Pankratov Nizhny Novgorod State University Nizhny Novgorod603950Russia

We introduce a model of redistribution of point radiation defects, their interaction between themselves and redistribution of their simplest complexes（divacancies and diinterstitials） in a multilayer structure. The model gives a possibility to describe qualitatively nonmonotonicity of distributions of concentrations of radiation defects on interfaces between layers of the multilayer structure. The nonmonotonicity was recently found *** take into account the nonmonotonicity we modify recently used in literature model for analysis of distribution of concentration of radiation defects. To analyze the model we used an approach of solution of boundary problems,which could be used without crosslinking of solutions on interfaces between layers of the considered multilayer structures.

关键词： radiation defects nonmonotonicity of distributions of concentrations complex

GUIDeD WAVeS IN MUlTIlAYeReD PlATeS: AN IMPROVeD ORTHOGONAl POlYNOMIAl APPROACH

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Acta Mechanica Solida Sinica 2014年第5期27卷 542-550页

作者： Jiangong Yu J.e.lefebvre l.elmaimouni School of Mechanical and Power engineering Henan Polytechnic University Department of Civil engineering University of Siegen Univ lille Nord de France F-59000 Lille France UVHC IEMN-DOAE F-59313 Valenciennes Cedex 9 France CNRS UMR 8520 F-59650 Villeneuve d’Ascq France eRSITA Faculte Polydisciplinaire d’Ouarzazate Univ. Ibn Zohr 45000 Ouarzazate Morocco lMTI Faculte des Sciences d’Agadir Universite Ibn Zohr BP 28/S Agadir Morocco

Conventional orthogonal polynomial approach can solve the multilayered plate only when the material properties of two adjacent layers do not change significantly. This paper de- veloped an improved orthogonal polynomial approach to solve wave propagation in multilayered plates with very dissimilar material properties. Through numerical comparisons among the exact solution, the results from the conventional polynomial approach and from the improved poly- nomial approach, the validity of the improved polynomial approach is illustrated. Finally, it is shown that the conventional polynomial approach can not yield correct continuous normal stress profiles. The improved orthogonul polynomial approach has overcome this drawback.

关键词： multilayered plate orthogonal polynomial dispersion curves stress profiles

A simple and fast method to calculate the coil currents and the external poloidal flux and magnetic field for fixed boundary equilibria

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Plasma Science and Technology 2024年第11期26卷 65-70页

作者： Ricardo FAReNGO Pablo l GARCÍA-MARTÍNeZ Hugo e FeRRARI Centro Atómico Bariloche Comisión Nacional de Energía AtómicaBariloche 8400Argentina Instituto Balseiro Universidad Nacional de CuyoBariloche 8400Argentina CONICeT CCT-Patagonia Norte Bariloche 8400Argentina

A simple and fast method to calculate the coil currents and the external poloidal flux and magnetic field consistent with a given internal magnetohydrodynamic(MHD) equilibrium and coil geometry is presented. The constrained optimization technique employed allows to fix the exact position of the X-points. The external poloidal flux and field are calculated using Green's functions expressed in terms of elliptic integrals that are calculated using a fast and accurate *** calculation can be limited to the region between the plasma and the device wall. An example for a double null configuration is presented.

关键词： MHD equilibrium Green's functions tokamak

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTlU İsmail e.KIlIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

Social learning contributions to the etiology and treatment of functional abdominal pain and inflammatory bowel disease in children and adults

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World Journal of Gastroenterology 2007年第17期13卷 2397-2403页

作者： Rona l levy Shelby l langer William e Whitehead School of Social Work University of WashingtonUnited States Center for Functional GI and Motility Disorders University-of-North-Carolina-at-Chapel-Hill-United-State

This paper reviews empirical work on cognitive and social learning contributions to the etiology and treatment of illness behavior associated with functional abdominal pain and inflammatory bowel disease. A particular emphasis is placed on randomized controlled trials, the majority of which are multi-modal in orientation, incorporating elements of cognitive behavioral therapy, social learning, and relaxation. Based on this review, we offer methodological and clinical suggestions: (1) Research investigations should include adequate sample sizes, long-term follow-up assessments, and a credible, active control group. (2) Standard gastrointestinal practice should include, when appropriate, learning opportunities for patients and family members, for example, instruction regarding the encouragement of wellness behavior.

关键词： Functional abdominal pain Cognitivebehavioral therapy Social learning Irritable bowelsyndrome Inflammatory bowel disease Illness behavior

Numerical studies towards practical large-eddy simulation

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Journal of Thermal Science 2007年第4期16卷 328-336页

作者： J.Boudet J.Caro l.Shao e.lév(?)que lMFA laboratoire

large-eddy simulation developments and validations are presented for an improved simulation of turbulent internal flows. Numerical methods are proposed according to two competing criteria： numerical qualities （precision and spectral characteristics）, and adaptability to complex configurations. First, methods are tested on academic test-cases, in order to abridge with fundamental studies. Consistent results are obtained using adaptable finite volume method, with higher order advection fluxes, implicit grid filtering and ＂low-cost＂ shear-improved Smagorinsky model. This analysis particularly focuses on mean flow, fluctuations, two-point correlations and spectra. Moreover, it is shown that exponential averaging is a promising tool for leS implementation in complex geometry with deterministic unsteadiness. Finally, adaptability of the method is demonstrated by application to a configuration representative of blade-tip clearance flow in a turbomachine.

关键词： leS adaptable methods validation