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Shear reinforcement effect of reinforced concrete tie-columns on the lateral resistance of confined masonry walls

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 313-324页

作者： samir Bouhedja Abdelkrim Bourzam Ahmed Boukhaled Ammar Nechnech University of Sciences and Technology Houari Boumediene(USTHB)Faculty of Civil EngineeringLaboratory of EnvironmentWaterGeomechanics and Structures(LEEGO)BP 32 El AliaBab EzzouarAlgiers16111Algeria University of Sciences and Technology Houari Boumediene(USTHB)Faculty of Civil EngineeringLaboratory of Built Environment Research(LBE)BP 32 El AliaBab EzzouarAlgiers16111Algeria

Tie-columns improve significantly the lateral resistance of masonry bearing walls against persistent, transient and accidental loads. The research work described herein has been carried out to assess the lateral resistance of confined masonry walls, where contribution of the masonry panel is evaluated according to material mechanics and tie-columns effect is estimated by a proposed analytical formulation based on a model reported on previously. This approach takes into account the effect of dowel support on the reaction of its adjacent shear reinforcement： the conditions for the various contributions of transverse reinforcements are better defined following a clear evaluation of the participation ratio of these reinforcements. Lateral resistances of confined masonry walls measured in full-scale tests and gleaned from the literature are compared and checked with resistances calculated using the present approach.

关键词： reinforcement columns confined reinforced walls Shear formulation panel participation herein

The xanthate route to all-carbon quaternary centers

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Science China Chemistry 2019年第11期62卷 1450-1462页

作者： Béatrice Quiclet-Sire samir Z.Zard Laboratoire de Synthèse Organique Ecole Polytechnique

This review discusses the numerous routes to all-carbon quaternary centers based on the unique radical chemistry of xanthates. Itsummarizes the various approaches to the synthesis of tertiary xanthates then describes the intra- and intermolecular radicaladditions and combinations thereof that have so far been used to construct quaternary centers.

关键词： xanthates quaternary centers radical addition cyclization tandem reactions

Microstructure of coupled Al/gray cast iron obtained by molding and its effect on mass loss

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China Foundry 2018年第5期15卷 378-383页

作者： Mohamed Bouitna Naima Boutarek-Zaourar samir Mansour samir Mourad Chentouf Eric Mossang Laboratory of Materials Technology Faculty of Mechanical Engineering and Process EngineeringUniversity of Science and Technology Houari BoumedieneB.P.32 El Alia16111 AlgiersAlgeria Department of Mechanical Engineering School of Technology Superior1100 Notre-Dame Street WestMontrealQuebec H3C 1K3Canada NEEI Institute National Center for Scientific Research25rue des MartyrsBO 16638042Grenoble CedexFrance

This study aims to consolidate the surface of gray cast iron with aluminum deposition by developing a method that combines the preparation and surface treatment in a single operation. The effect of the wall thickness of the castings on the microstructure of the formed layers was studied, and two thicknesses, 8 mm and 25 mm, were studied. The formation of a continuous and homogeneous rich aluminum layer on the surface of the cast iron was observed. The formed layer is composed of two successive zones identified as two proeutectoid phases FeAl+FeAl/FeAl2 and single-phase FeAl, which significantly increases the surface hardness. Furthermore, this change in surface composition makes it possible to reduce the mass of the immersed samples in a 1 M hydrochloric acid solution during different exposure times(1 to 4 days). Consequently, a clear improvement in the corrosion resistance of the treated layers is highlighted.

关键词： gray cast iron aluminum coating treatment in the mold mass loss

Association of hepatitis C virus infection and diabetes

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World Journal of Gastroenterology 2009年第40期15卷 5114-5115页

作者： samir Rouabhia Rachid Malek Hocine Bounecer Department of Internal Medicine University Hospital Center Touhami Benflis Department of Internal Medicine University Hospital Center Saadna Abdenour Department of Epidemiology and Preventive Medicine University Hospital Center Touhami Benflis

Epidemiologic studies have suggested a relation between hepatitis C virus (HCV) infection and diabetes mellitus. HCV infection is emerging as a metabolic disease, and diabetes mellitus as a risk factor for HCV infection. However, some data on the prevalence of antibodies to HCV in patients with diabetes are conflicting. These seroprevalence data should be interpreted with caution. Some potential bias may occur in those clinic-based studies that target a specif ic disease group. In this letter we explain some reasons for these conflicting studies.

关键词： Prevalence Hepatitis C Diabetes mellitus

Existence Results for a Class of Periodic Evolution Variational Inequalities

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Chinese Annals of Mathematics,Series B 2007年第6期28卷 629-650页

作者： samir ADLY Daniel GOELEVEN Michel THRA DMI-XLIM UMR-CNRS 6172Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. IREMIA Université de La Réunion97400 Saint-DenisFrance.

In this paper, using the Brouwer topological degree, the authors prove an existence result for finite variational inequalities. This approach is also used to obtain the existence of periodic solutions for a class of e... 详细信息

关键词： Variational inequalities Differential inclusions Topological degree Guiding functions Periodic solutions

Cameron ulcers:An atypical source for a massive upper gastrointestinal bleed

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World Journal of Gastroenterology 2012年第35期18卷 4959-4961页

作者： samir Kapadia Sophia Jagroop Atul Kumar Department of Medicine Stony Book Univer sity School of MedicineStony BrookNY 11794United States Gastroenterology and Hepatol ogy Northport VA Medical CenterNorthportNY 11768United States

Cameron lesions represent linear gastric erosions and ulcers on the crests of mucosal folds in the distal neck of a hiatal hernia(HH).Such lesions may be found in upto 50% of endoscopies performed for another *** typically asymptomatic,these may rarely present as acute,severe upper gastrointestinal bleed(GIB).The aim is to report a case of a non-anemic 87-year-old female with history of HH and atrial fibrillation who presented with hematemesis and melena resulting in hypovolemic *** esophagogastroduodenoscopy was required to identify multiple Cameron ulcers as the *** in a patient with HH should involve meticulous visualization of hernia neck and surrounding *** ulcers should be considered in all patients with severe,acute GIB and especially in those with known HH with or without chronic anemia.

关键词： Cameron lesion Upper gastrointestinalbleeding Shock Hiatal hernia

Regulation of kidney development by the Mdm2/Mdm4-p53 axis

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Journal of Molecular Cell Biology 2017年第1期9卷 26-33页

作者： samir El-Dahr Sylvia Hilliard Zubaida Saifudeen Department of Pediatrics Section of Pediatric Nephrology Tulane University School of Medicine New Orleans LA 70112 USA

While p53 activity is required for tumour suppression, unconstrained p53 activity on the other hand is detrimental to the organism, resulting in inappropriate cellular death or proliferation defects. Unimpeded p53 activity is lethal in the developing embryo, under- lining the need for maintaining a tight control on p53 activity during this period. The critical role of the negative regulators of p53, Mdm2 and Mdm4, in vertebrate development came to light by fatal disruption of embryogenesis that was observed with Mdm2 and Mdm4 gene deletions in mice. Embryonic lethality was rescued only by superimposing p53 removal. Here we summarize the contri- bution of the Mdm2/Mdm4-p53 axis that occurs at multiple steps of kidney development. Conditional, cell type-specific deletions reveal distinct functions of these proteins in renal morphogenesis. The severe impact on the renal phenotype from targeted gene deletions underscores the critical role played by the Mdm2/Mdm4-p53 nexus on nephrogenesis, and emphasizes the need to monitor patients with aberrations in this pathway for kidney function defects and associated cardiovascular dysfunction.

关键词： progenitor nephrogenesis embryonic metanephric Mdm2/MdmX/p53

Fractional order extremum seeking approach for maximum power point tracking of photovoltaic panels

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Frontiers in Energy 2015年第1期9卷 43-53页

作者： Ammar NECAIBIA samir LADACI Abdelfatah CHAREF Jean Jacques LOISEAU Research Unit in Renewable Energies in the Saharan Medium CDEREPST URER-MS Adrar 01000 Algeria Department ofElectrical Engineering University of Skikda Skikda 21000 Algeria Department of Electronics Electrotechnics and Automatics NationalPolytechnic School of Constantine Constantine 25000 Algeria SP-LabLaboratory Department of Electronics University of Constantine 1Constantine 25000 Algeria SP-Lab Laboratory Department of Electronics University of Con-stantine 1 Constantine 25000 Algeria Research Institute in Communications and Cybernetics CNRS UMR6597 1 rue de la No~ 44321 Nantes France

Due to the high interest in renewable energy and diversity of research regarding photovoltaic （PV） array, a great research effort is focusing nowadays on solar power generation and its performance improvement under various weather conditions. In this paper, an integrated framework was proposed, which achieved both maximum power point tracking （MPPT） and minimum ripple signals. The proposed control scheme was based on extremum- seeking （ES） combined with fractional order systems （FOS）. This auto-tuning strategy was developed to maximize the PV panel output power through the regulation of the voltage input to the DC/DC converter in order to lead the PV system steady-state to a stable oscillation behavior around the maximum power point （MPP）. It is shown that fractional order operators can improve the plant dynamics with respect to time response and disturbance rejection. The effectiveness of the proposed controller scheme is illustrated with simulations using measured solar radiation data.

关键词： extremum seeking (ES) fractional ordercontrol (FOC) fractional calculus photovoltaic (PV)

Periodic Solutions of Evolution Variational Inequalities—a Method of Guiding Functions

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Chinese Annals of Mathematics,Series B 2009年第3期30卷 261-272页

作者： samir ADLY Daniel GOELEVEN Michel THRA Département de Math'ematiques et Informatique Laboratoire XLIM(Unité Mixte 6172 du CNRS)Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. Laboratoire d' Informatique et de Mathématiques Université de La Réunion97400 Saint-DenisFrance.

This paper focuses on a part of the presentation given by the third author at the Shanghai Forum on Industrial and Applied Mathematics(Shanghai 2006).It is related to the existence of a periodic solution of evolution ... 详细信息

关键词： Variational inequality Differential inclusion Topological degree Guiding function Periodic solution