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Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.el jariri F.L.Sefyani A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib M.Sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPM ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(Morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko ***,we found that the Van Hoof effect is also modulated by the Blazhko ***,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

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Designing a Protection Scheme in Micro-Grid Systems with DG Using Central Protection Unite and Multiple Setting Group Protection Relays

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Journal of Power and Energy Engineering 2024年第9期12卷 37-49页

作者： Mostafa I. Saleh Gaber el-Saady Ali M. Yousef el-Noby A. Ibrahim Alfanar Company Mecca Saudi Arabia Department of electrical Engineering Faculty of Engineering Asyut University Asyut Egypt

Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this continuous changes in generation condition, the fault current level in network will be affected, this changes in fault current level will affect in the coordination between protection relays and to keep the coordination at right way, an adaptive protection system is required that can adaptive its setting according to generation changes, the fault current level in each case is evaluated using ETAP software, and the required relay setting in each case is also evaluated using Grey Wolf Optimizer (GWO) algorithm, and to select suitable setting which required in each condition, to select the active setting group of protection relay according to generation capacity, central protection unite can be used, and to improve protection stability and minimizing relays tripping time, a proposed method for selecting suitable backup relay is used, which leads to decrease relays tripping time and increase system stability, output settings for relays in all cases achieved our constrains.

关键词： Directional Overcurrent Relay Protection Coordination Distributed Generators Central Protection Unite Multiple Setting Group Protection Relay

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Study of Hygrothermal Behavior of Bio-Sourced Material Treated Ecologically for Improving Thermal Performance of Buildings

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Journal of Renewable Materials 2024年第5期12卷 1007-1027页

作者： Soumia Mounir Miloudia Slaoui Youssef Maaloufa Fatima Zohra el Wardi Yakubu Aminu Dodo Sara Ibn-elhaj Abdelhamid Khabbazi National School of Architecture Agadir New Complex Ibn Zohr AgadirHay dakhla80000Morocco EMDD CERNE2DUniversity Mohammed V in RabatEst SaléSaléMedinaMorocco Physics Department LPMAT LaboratoryFaculty of Sciences Ain ChockHassan II UniversityCasablancaMorocco Architectural Engineering Department College of Engineering Najran UniversityNajran66426Saudi Arabia The Centre of Scientific and Engineering Research Najran UniversityNajranSaudi Arabia

Creating sustainable cities is the only way to live in a clean environment,and this problem can be solved by using bio-sourced and recycled *** this purpose,the authors contribute to the valuation of sheep wool waste as an eco-friendly material to be used in *** paper investigates the thermal,hygrothermal,and biological aspects of sheep wool by testing a traditional *** biological method of aerobic mesophilicﬂora has been *** X was used to determine the chemical composition of the materials ***,thermal characterization has been *** thermal conductivity is above 0.046(W·m^(-1)·K^(-1))and the thermal diffusivity is 1.56.10^(-6) m^(2)·s^(-1).Besides,the energy efﬁciency of using sheep wool in buildings was ***,its humidity behavior was evaluated in different aspects in both winter and *** of biological analyses show the efﬁciency of the treatment by removing the majority of the microorgan-isms:the value of yeast and mildew was reduced from 38.10^(2) to 2.10^(2)(UFC·g^(-1)).In addition to that,sheep wool permits obtaining a low thermal transmittance on the scale of the walls and low cooling needs on the scale of the building with a gain of 45%and 52%,respectively.

关键词： Sustainability sheep wool biological treatment hygrothermal wool behavior hot wire method

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Stem cell transplantation in cerebrovascular accidents:A global bibliometric analysis(2000-2023)

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World Journal of Stem Cells 2024年第9期16卷 832-841页

作者： Jad el Masri Ahmad Afyouni Maya Ghazi Karim Hamideh Israe Moubayed Abdo Jurjus Hanine Haidar Ruzanna Petrosyan Pascale Salameh Hassan Hosseini École Doctorale Sciences de la Vie et de la Santé UniversitéParis-Est CréteilCréteil 94010France INSERM U955-E01 Institut Mondor de Recherche BiomédicaleUniversitéParis-Est CréteilCréteil 94000France Faculty of Medical Sciences Lebanese UniversityBeirut 1533Lebanon Department of Anatomy Cell Biology and Physiological SciencesFaculty of MedicineAmerican University of BeirutBeirut 1107Lebanon Department of Neurology Faculty of MedicineLebanese American UniversityBeirut 1102Lebanon Department of Pathology Faculty of MedicineLebanese American UniversityBeirut 1102Lebanon Faculty of Pharmacy Lebanese UniversityBeirut 1102Lebanon Faculty of Medicine Lebanese American UniversityBeirut 1102Lebanon Department of Primary Care and Population Health University of Nicosia Medical SchoolNicosia 2408Cyprus Institut National de SantéPublique d'Épidémiologie Clinique et de Toxicologie-Liban Beirut 1103Lebanon Department of Neurology Henri Mondor HospitalAP-HPCréteil 94000France

BACKGROUND Cerebrovascular accident(CVA)is a major global contributor to death and *** part of its medical management,researchers have recognized the importance of promising neuroprotective strategies,where stem cell transplantation(SCT)is thought to confer advantages via trophic and neuroprotective *** To evaluate the current state of research on SCT in patients with CVA,assess key trends and highlight literature *** PubMed was screened for SCT in CVA-related articles in October 2023,for each country during the period between 2000 and *** the World Bank data,total population and gross domestic product were collected for ***_1.6.19 was used to create the VOS figure using the results of the same *** and tables were obtained using Microsoft Office *** A total of 6923 studies were identified on SCT in CVA,making 0.03%of all published studies ***,68%were conducted in high-income countries,with a significant focus on mesenchymal stem *** journal“Stroke”featured the largest share of these articles,with mesenchymal SCT having the highest rate of inclusion,followed by hematopoietic *** time,there has been a noticeable shift from in vitro studies,which assess stem cell proliferation and neurogenesis,to in vivo studies aimed at evaluating efficacy and ***,the number of reviews increased along this *** This bibliometric analysis provides a comprehensive guide for physicians and researchers in the field through an objective overview of research activity,and highlights both current trends and *** a potential therapeutic role in CVA,more research is needed in the future to focus on different aspects of SCT,aiming to reach a better treatment strategy and improve life quality in patients.

关键词： Bibliometric analysis PubMed Stem cell transplantation Cerebrovascular accidents Stroke

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Optimizing wind farm layout for enhanced electricity extraction using a new hybrid PSO-ANN method

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Global Energy Interconnection 2024年第3期7卷 254-269页

作者： Mariam el Jaadi Touria Haidi Abdelaziz Belfqih Mounia Farah Atar Dialmy LAGES Laboratory Hassania School of Public Works(EHTP)Casablanca 20230Morocco LESE Laboratory National School of Electricity and Mechanics(ENSEM)Casablanca 20100Morocco LAGCET Laboratory Hassania School of Public Works(EHTP)Casablanca 20230Morocco

With the growing need for renewable energy,wind farms are playing an important role in generating clean power from wind *** best wind turbine architecture in a wind farm has a major influence on the energy extraction *** paper describes a unique strategy for optimizing wind turbine locations on a wind farm that combines the capabilities of particle swarm optimization(PSO)and artificial neural networks(ANNs).The PSO method was used to explore the solution space and develop preliminary turbine layouts,and the ANN model was used to fine-tune the placements based on the predicted energy *** proposed hybrid technique seeks to increase energy output while considering site-specific wind patterns and topographical *** efficacy and superiority of the hybrid PSO-ANN methodology are proved through comprehensive simulations and comparisons with existing approaches,giving exciting prospects for developing more efficient and sustainable wind *** integration of ANNs and PSO in our methodology is of paramount importance because it leverages the complementary strengths of both ***,this novel methodology harnesses historical data through ANNs to identify optimal turbine positions that align with the wind speed and direction and enhance energy extraction efficiency.A notable increase in power generation is observed across various *** percentage increase in the power generation ranged from approximately 7.7%to 11.1%.Owing to its versatility and adaptability to site-specific conditions,the hybrid model offers promising prospects for advancing the field of wind farm layout optimization and contributing to a greener and more sustainable energy future.

关键词： Layout optimization Turbine placement Wind energy Hybrid optimization Particle swarm optimization Artificial neural networks Renewable energy Energy efficiency

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Development and Validation of a Scaled electric Combat Vehicle Tire Model

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World Journal of Engineering and Technology 2024年第1期12卷 24-39页

作者： Haniyeh Fathi Aricha Mehrotra Zeinab el-Sayegh Department of Automotive and Mechatronics Engineering Ontario Tech University Oshawa Canada

Pneumatic tire modeling and validation have been the topic of several research papers, however, most of these papers only deal with pneumatic passenger and truck tires. In recent years, wheeled-scaled vehicles have gained lots of attention as a feasible testing platform, nonetheless up to the authors’ knowledge there has been no research regarding the use of scaled tires and their effect on the overall vehicle performance characteristics. This paper presents a novel scaled electric combat vehicle tire model and validation technique. The pro-line lockdown tire size 3.00 × 7.35 is modeled using the Finite element Analysis (FEA) technique and several materials including layered membrane, beam elements, and Mooney-Rivlin for rubber. The tire-rim assembly is then described, and the rigid body analysis is presented. The tire is then validated using an in-house custom-made static tire testing machine. The tire test rig is made specifically to test the pro-line tire model and is designed and manufactured in the laboratory. The tire is validated using vertical stiffness and footprint tests in the static domain at different operating conditions including several vertical loads. Then the tire is used to perform rolling resistance and steering analysis including the rolling resistance coefficient and the cornering stiffness. The analysis is performed at different operating conditions including longitudinal speeds of 5, 10, and 15 km/h. This tire model will be further used to determine the tractive and braking performance of the tire. Furthermore, the tire test rig will also be modified to perform cornering stiffness tests.

关键词： Tire Modeling Tire Testing Machine Vehicle Dynamics Unmanned Vehicle Modeling Finite element Analysis Tire Mechanics

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Assessing the Water-Energy-Food-Ecosystems Nexus in Smart Irrigation: A Potato Farming Case Study in Lebanon

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Journal of Geoscience and Environment Protection 2024年第8期12卷 80-96页

作者： Ali Karnib Hammou Laamrani Jauad el Kharraz Liberal Education Department Lebanese American University Beirut Lebanon United Nations ESCWA Beirut Lebanon Regional Center for Renewable Energy & Energy Efficiency (RCREEE) Cairo Egypt

This study examines the Water-Energy-Food-Ecosystems (WEFE) nexus in Lebanese agriculture, with a focus on the shift from conventional surface irrigation techniques to advanced smart irrigation systems in the Bekaa region, specifically targeting potato cultivation. The study quantitatively analyzes the interaction among water, energy, and agricultural outputs at the farm scale using the WEFE Nexus framework for scenario analysis. It evaluates variations in water productivity, environmental effects, and economic outcomes, offering a detailed view of existing practices and their sustainable improvement potential. The WEFE Nexus assessment demonstrates that smart irrigation integration significantly decreased resource usage: water consumption was reduced by 58%, diesel fuel use for irrigation dropped by 57%, and the demand for labor and fertilizers decreased by 47% and 49%, respectively. This change led to enhanced crop yields and increased resource efficiency, demonstrating the potential of smart irrigation as a transformative strategy for sustainable agriculture in Lebanon and other arid areas. Economic analysis showed that farmers could recover the costs of installing the smart irrigation system within 3 months. The findings highlight the need for further research on integrating smart irrigation with renewable energy, showing potential for sustainable agricultural development. .

关键词： Water-Energy-Food-Ecosystems Nexus Sustainable Agriculture Smart Irrigation Q-Nexus Model

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Analysis of cerium substitution in Co-Sr based spinel ferrites for high frequency application

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Journal of Rare Earths 2024年第9期42卷 1755-1763,I0005页

作者： Laura Khudaysh Inas A.Ahmed Syeda Rabia Ejaz Sajjad Ahmad Khan Yasir A.Haleem Mohamed M.Ibrahim Mahmood Ali Hafiz Muhammad Tahir Farid Zeinhom M.el-Bahy Department of Physics Faculty of ScienceJazan UniversityJazan45142Saudi Arabia Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha62224Saudi Arabia Department of Physics The Government Sadiq College Women UniversityBahawalpur63100Pakistan Institute of Physics Khwaja Fareed University of Engineering and Information TechnologyRahim Yar Khan64200Pakistan Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Centre of Excellence in Solid State Physics University of the PunjabLahorePakistan Department of Physics Government CollegeTaunsa Sharif32200Pakistan Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt

Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic *** sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co_(0.6)Sr_(0.4)Ce_(x)Fe_(2-x)O_(4). Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized *** the utilization of the M-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and *** ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation *** logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is *** a change in the amount of cerium,the activation energy goes up from 0.19 to *** changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were *** the frequency goes up,the dielectric constant goes *** ferrites that have been made better in every way can be used in high-frequency applications.

关键词： Activation energy DC electrical resistance Remanence magnetization Cobalt strontium spinel ferrites High frequency application Rare earths

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Primary Hyperoxaluria Type 1 in Adulthood: Case Series

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Open Journal of Nephrology 2024年第3期14卷 350-360页

作者： Sara el Maakoul Nada el Kadiri Nabil Hmaidouch Salma Belmokadem Loubna Benamar Tarik Bouattar Naima Ouzeddoun Department of Nephrology Dialysis Renal Transplantation Ibn Sina University Hospital-Rabat Rabat Morocco Faculty of Medicine and Pharmacy Mohammed V University Rabat Morocco

Introduction: Primary hyperoxaluria type 1 (HP1) is a rare lithiasis with systemic involvement, due to the accumulation of calcium oxalate crystals. In the absence of therapeutic management, it progresses to end-stage chronic renal failure. The aim of this study is to describe and analyse the observations of our patients with HP1. Patients and methods: This is a retrospective study carried out between 2014 and 2023 in the Nephrology-Dialysis Transplant Department of the Ibn Sina University Hospital in Rabat. The clinical, paraclinical and evolutionary elements were taken from the patients’ medical records. Results: We collected 11 cases, with a mean age of 27 ± 8.5 years and a M/F sex ratio of 1.7. The diagnosis of HP1 was made on the basis of genetic analysis in 8 patients, morphological and spectro-photometric analysis of the calculus in one patient, biopsy of the graft in one patient and crystalluria and a family history of PH1 in one patient. Two patients died, and 8 patients were on chronic haemdialysis with systemic damage. Only one patient maintained a stable GFR at 60 ml/min. Conclusion: Early diagnosis combined with conservative treatment is the only way to limit the rapid progression of this disease. This requires awareness and collaboration between nephrologists, urologists and biologists within a specialised team.

关键词： Primary Hyperoxaluria Adulthood Kidney Disease

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Pattern of Potential Laboratory Markers for COVID-19 in Eastern Sudan

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Open Journal of Epidemiology 2024年第3期14卷 508-516页

作者： Nazik Sir el Khatim Bakhit Suliman Mohammed Omer Abaker Gibreel Mervat Sir el Khatim Bakhit Suliman Department of Clinical Chemistry College of Medical Laboratory Science Eastern Sudan University of Medical Science and Technology Port Sudan Sudan Dean of the Secretariat of Academic Affairs Port Sudan Ahlia University Port Sudan Sudan Cardiology Department Cath Lab Fujaira Hospital Fujaira UAE

Background: Coronavirus disease 2019 (COVID-19) is a recent global health crisis. One of the major issues of COVID-19 is its unpredictable manifestations and serious outcomes. Many hematological parameters are thought to change dramatically during the course of the disease. These include white blood cells, red blood cells, and platelets. This study aimed at evaluating certain laboratory results;peripheral blood lymphopenia, relative neutrophilia, high neutrophil-lymphocyte ratio, and elevated C-reactive protein as potential laboratory markers of COVID-19 in Eastern Sudanese patients. Methods: We, retrospectively, aimed at the evaluation of peripheral blood leucocytes count, neutrophil-lymphocyte ratio NLR and C-reactive protein (CRP) levels in confirmed COVID-19 eastern Sudanese patients during the course of the disease. Results: The mean total leucocytes count, % neutrophils count, absolute neutrophils count and C-reactive protein (CRP) were significantly higher (P. value = 0.000) in COVID-19 patients than in the control group while the mean % lymphocytes count and % mixed cells count were found to be significantly lower in COVID-19 patients than in the control group (P. value 0.000). Conclusion: Peripheral blood leucocyte alterations (simultaneous presence of lymphopenia, relative neutrophilia and high neutrophil lymphocyte ratio (NLR) along with elevated CRP levels may be valuable biomarkers associated with COVID-19 in Port Sudan city, Red Sea state, Sudan. These markers might be important in prediction, inspection of disease progression and prognosis.

关键词： COVID-19 SARS 2 WBCs CRP NLR Port Sudan

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