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Spectral lags of flaring events in LS I+61°303 from RXTE Observations

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Research in Astronomy and Astrophysics 2016年第7期16卷 29-38页

作者： Tamal Sarkar samir Sarkar Arunava Bhadra High Energy&Cosmic Ray Research Centre University of North BengalSiliguriWB 734013India University Science Instrumentation Centre University of North BengalSiliguriWB 734013India

This work reports the first discovery of（negative） spectral lags in X-ray emission below 10 ke V from the gamma ray binary LS I＋61？303 during large flaring episodes using Rossi X-ray Timing Explorer（RXTE） observations. It is found from the RXTE data that during the flares, low energy（3–5 ke V） variations lead the higher energy（8–10 ke V） variations by a few tens of seconds whereas no significant time lag is observed during the non-flaring states. The observed spectral lag features for flaring events suggest that inverse Compton scattering may be operating, at least in some part of the system. Another possibility is that the sites of particle acceleration may be different for flaring and non-flaring events such as in the microquasar model, in which the flaring radiation may come from hot spots sitting above the black hole while steady state emissions are due to the jets.

关键词： X-rays:binaries X-rays:individual(LS I+61?303)

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：丙型肝炎病毒病毒感染糖尿病代谢性疾病协会流行病学危险因素集成电路

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：上消化道出血溃疡非典型梅 GIB 血容量源识别可视化

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)

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

当 p53 活动为瘤抑制被要求时，非强迫的 p53 活动在另一方面对有机体有害，导致不恰当的细胞的死亡或增长缺点。未受阻碍的 p53 活动在发展中的胚胎是致命的，加重对维持在在这个时期期间的 p53 活动的紧密的控制的需要。p53， Mdm2 和... 详细信息

当 p53 活动为瘤抑制被要求时，非强迫的 p53 活动在另一方面对有机体有害，导致不恰当的细胞的死亡或增长缺点。未受阻碍的 p53 活动在发展中的胚胎是致命的，加重对维持在在这个时期期间的 p53 活动的紧密的控制的需要。p53， Mdm2 和 Mdm4 的否定管理者的关键角色，在脊椎动物，开发由在老鼠与 Mdm2 和 Mdm4 基因删除被观察的 embryogenesis 的致命的混乱真相大白。胚胎的致命性仅仅由附加 p53 移动被救。这里，我们总结发生在肾开发的多重步的 Mdm2/Mdm4-p53 轴的贡献。有条件，房间类型特定的删除在肾的形态发生揭示这些蛋白质的不同功能。从指向的基因删除的肾的显型上的严重影响强调 Mdm2/Mdm4-p53 连结在 nephrogenesis 上起的关键作用，并且强调需要为肾函数缺点和联系心血管的机能障碍在这条小径与错误监视病人。

关键词：祖先 nephrogenesis 胚胎 metanephric Mdm2/MdmX/p53

Renal calcification in children with renal tubular acidosis:What a paediatrician should know

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World Journal of Clinical Pediatrics 2023年第5期12卷 295-309页

作者： Mohammed Al-Beltagi Nermin Kamal Saeed Adel Salah Bediwy Reem Elbeltagi samir Hasan Mohamed Basiony Hamza Department of Pediatrics Faculty of MedicineTanta UniversityTanta 31511AlghrabiaEgypt Department of Pediatrics University Medical CenterKing Abdulla Medical CityDr.Sulaiman Al Habib Medical GroupManamaBahrainManama 26671ManamaBahrain Medical Microbiology Section Department of PathologySalmaniya Medical ComplexMinistry of HealthKingdom of BahrainManama 12ManamaBahrain Medical Microbiology Section Department of PathologyIrish Royal College of SurgeonBahrainBusaiteen 15503MuharraqBahrain Department of Pulmonology Faculty of MedicineTanta UniversityTanta 31527AlghrabiaEgypt Department of Chest Disease University Medical CenterKing Abdulla Medical CityArabian Gulf UniversityDr.Sulaiman Al Habib Medical GroupManamaManama 26671ManamaBahrain Department of Medicine The Royal College of Surgeons in Ireland-BahrainBusiateen 15503MuharraqBahrain Department of Pediatrics Faculty of MedicineTanta University HospitalTanta 31511AlgharbiaEgypt Department of Pediatrics Faculty of MedicineTanta UniversityTanta 31511AlgharbiaEgypt

Renal tubular acidosis(RTA)can lead to renal calcification in children,which can cause various complications and impair renal *** review provides pediatricians with a comprehensive understanding of the relationship between RTA and renal calcification,highlighting essential aspects for clinical *** article analyzed relevant studies to explore the prevalence,risk factors,underlying mechanisms,and clinical implications of renal calcification in children with *** show that distal RTA(type 1)is particularly associated with nephrocalcinosis,which presents a higher risk of renal ***,there are limitations to the existing literature,including a small number of studies,heterogeneity in methodologies,and potential publication *** data and control groups are also lacking,which limits our understanding of longterm outcomes and optimal management strategies for children with RTA and renal *** play a crucial role in the early diagnosis and management of RTA to mitigate the risk of renal calcification and associated *** addition,alkaline therapy remains a cornerstone in the treatment of RTA,aimed at correcting the acid-base imbalance and reducing the formation of kidney ***,early diagnosis and appropriate therapeutic interventions are paramount in preventing and managing renal calcification to preserve renal function and improve long-term outcomes for affected *** research with larger sample sizes and rigorous methodologies is needed to optimize the clinical approach to renal calcification in the context of RTA in the pediatric population.

关键词： Renal tubular acidosis Nephrocalcinosis Renal calcification Hypercalciuria Kidney stones Metabolic acidosis Children