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Boundedness of Rough Operators on Grand Variable Herz Spaces

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Applied Mathematics 2021年第7期12卷 614-626页

作者： bechir mahamat Acyl Shuangping Tao Omer Khalill College of Mathematics and Statistics Northwest Normal University Lanzhou China Faculty of Sciences and Technology Adam Barka University of Abeche Abeche Chad Faculty of Education Sudan University of Science and Technology Khartoum Khartoum State Sudan

In this paper, we prove the boundedness of Calderón-Zygmund singular integral operators TΩ on grand Herz spaces with variable exponent under some conditions.

关键词： Calderón-Zygmund Singular Integral Operator Grand Herz Spaces Variable Exponent

Global Bounded Solutions for the Keller-Segel Chemotaxis System with Singular Sensitivity

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Applied Mathematics 2020年第10期11卷 985-990页

作者： Khalid Ahmed Abbakar Omer Khalil Alhussein Mohamed bechir mahamat Abdoulaye Ali Abeer Alhadi College of Mathematics and Statistics Northwest Normal University Lanzhou China Department of Mathematics and Physics Faculty of Education University of Gadarif Gadarif Sudan College of Physics and Electronic Engineering Northwest Normal University Lanzhou China

In this paper, we consider the Neumann initial-boundary value problem for the Keller-Segel chemotaxis system with singular sensitivity (0.1) is considered in a bounded domain with smooth boundary, Ω ⊂Rn (n ≥ 1), where d1 > 0, d2 > 0 with parameter χ ∈ R. When d1 = d2 + χ, satisfying for all initial data 0 ≤ n0 ∈ C0 and 0 v0∈ W1,∞ (Ω), we prove that the problem possesses a unique global classical solution which is uniformly bounded in Ω × (0, ∞).

关键词： Keller-Segel System Chemotaxis Global Bounded Solution Singular Sensitivity

Uniqueness of Positive Radial Solutions for a Class of Semipositone Systems on the Exterior of a Ball

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Applied Mathematics 2021年第3期12卷 131-146页

作者： Alhussein Mohamed Khalid Ahmed Abbakar Abuzar Awad Omer Khalil bechir mahamat Acyl Abdoulaye Ali Youssouf Mohammed Mousa College of Mathematics and Statistics Northwest Normal University Lanzhou China Department of Mathematics and Physics Faculty of Education University of Gadarif Gadarif Sudan Department of Science College of Education Sudan University of Science and Technology Khartoum Sudan

In this paper, we study the positive radial solutions for elliptic systems to the nonlinear BVP: , where Δu = div (∇u) and Δv = div (∇v) are the Laplacian of u, λ is a positive parameter, Ω = {x ∈ Rn : N > 2, |x| > r0, r0 > 0}, let i = [1,2] then Ki :[r0,∞] → (0,∞) is a continuous function such that limr→∞ ki(r) = 0 and is The external natural derivative, and : [0, ∞) → (0, ∞) is a continuous function. We discuss existence and multiplicity results for classes of f with a) fi > 0, b) fi fi = 0. We base our presence and multiple outcomes via the Sub-solutions method. We also discuss some unique findings.

关键词： Elliptic System Positive Radial Solution Exterior Domains Fixed Point Index

FlowBreakdown of Hybrid Nanofluid on a Rigid Surface with Power Law Fluid as Lubricated Layers

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1485-1499页

作者： Mirza Naveed Jahangeer Baig NadeemSalamat Sohail Nadeem NaeemUllah Mohamed bechir Ben Hamida Hassan Ali Ghazwani Sayed M.Eldin A.S.Al-Shafay Instituite of Mathematics Khwaja Fareed University of Engineering and Information TechnologyRahim yar Khan64200Pakistan Department of Mathematics Quaid-I-Azam UniversityIslamabad44000Pakistan Department of Mathematics Wenzhou UniversityWenzhou325035China College of Engineering Department of Mechanical EngineeringImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11564Saudi Arabia Research Laboratory of Ionized Backgrounds and Reagents Studies(EMIR) Preparatory Institute for Engineering Studies of Monastir(IPEIM)University of MonastirMonastir5060Tunisia Higher School of Sciences and Technology of Hammam Sousse Department of PhysicsJazan82511Kingdom of Saudia Arabia Department of Mechanical Engineering Faculty of engineeringJazan UniversityP.O.Box 45124JazanKingdom of Saudia Arabia Center of Research Faculty of EngineeringFuture University in EgyptNew Cairo11835Egypt Department of Mechanical Engineering College of EngineeringPrince Sattam bin Abdulaziz UniversityAlkharj16436Saudi Arabia

Thiswork investigates an oblique stagnation point flowof hybrid nanofluid over a rigid surface with power lawfluidas lubricated layers. Copper (Cu) and Silver (Ag) solid particles are used as hybrid particles acting in water H2O asa base fluid. The mathematical formulation of flow configuration is presented in terms of differential systemthat isnonlinear in nature. The thermal aspects of the flow field are also investigated by assuming the surface is a heatedsurface with a constant temperature T. Numerical solutions to the governing mathematical model are calculatedby the RK45 algorithm. The results based on the numerical solution against various flow and thermal controllingparameters are presented in terms of line graphs. The specific results depict that the heat flux increases over thelubricated-indexed parameter.

关键词： Oblique stagnation point flow hybrid nanofluid lubricated layer magnetohydrodynamics

Social Services for Mobile Pastoralists： Cross-sector Strategy Based on ＂One Health＂

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Journal of Sociology Study 2012年第9期2卷 705-714页

作者： mahamat bechir Zinsstag Jakob mahamat Abdoulaye Schelling Esther Kessely Hamit Fokou Gilbert Moto Daugla Bonfoh Bassirou Tanner Marcel University of N'Djamena Chad Centre de Support en Sante lnternationale Chad Swiss Tropical and Public Health Institute/University ofBasel Swiss Centre Suisse de Recherche Scientifique Cite d'Ivoire

Mobile pastoralist communities in Sahel countries have serious problems of access to social services. Classic strategies for social services were always based on a single sector, focused on settled populations, and hardly reached mobile communities. This paper aims to show a cross‐sector approach as a part of solutions to provide social services for mobile pastoralist communities and describes the ongoing scaling‐up process. The method used is based on a transdisciplinary approach which involves target communities and authorities in all processes through workshops and site visits. Interventions adopted the concept of "one health" benefiting of an added value of closer cooperation between human and animal health. This approach was tested with joint interventions between human and animal health, which provided access to health services for unreached communities and saved resource when compared with single sector intervention. Such approaches could be extended to other social services within cross‐sector interventions such as the delivery of basic education in nomadic areas. Such a strategy was validated by the communities and authorities and was further transformed into a national programme after a series of six national stakeholders’ seminars. The cross‐sector intervention will provide a minimum package of services (MPS) without compromising the structural services.

关键词：社会服务动物健康移动牧民萨赫勒地区利益相关者资源保存保健服务

Fast and Accurate Thoracic SPECT Image Reconstruction

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Computer Modeling in Engineering & Sciences 2022年第5期131卷 881-904页

作者： Afef Houimli Issam Ben Mhamed bechir Letaief Dorra Ben-Sellem University of Tunis El Manar Higher Institute of Medical Technologies of TunisResearch Laboratory in Biophysics and Medical Technologies LR13ES07Tunis1006Tunisia University of Tunis Higher National School of Engineers of TunisSignal Image and Energy Management Laboratory:LR13 ES03 SIMEENSITMontfleury1008Tunisia Faculty of Medicine of Tunis University of Tunis El ManarTunis1007Tunisia Nuclear Medicine Department Salah AZAIEZ InstituteTunis1006Tunisia

In Single-Photon Emission Computed Tomography(SPECT),the reconstructed image has insufficient contrast,poor resolution and inaccurate volume of the tumor size due to physical degradation ***,nonstationary filtering of the projection or the slice is one of the strategies for correcting the resolution and therefore improving the quality of the reconstructed SPECT *** paper presents a new 3D algorithm that enhances the quality of reconstructed thoracic SPECT images and reduces the noise level with the best degree of *** suggested algorithm is composed of three *** first one consists of denoising the acquired projections using the benefits of the complementary properties of both the Curvelet transformand theWavelet transforms to provide the best noise *** second step is a simultaneous reconstruction of the axial slices using the 3D Ordered Subset Expectation Maximization(OSEM)*** last step is post-processing of the reconstructed axial slices using one of the newest anisotropic diffusion models named Partial Differential Equation(PDE).The method is tested on two digital phantoms and clinical bone SPECT images.A comparative study with four algorithms reviewed on state of the art proves the significance of the proposed *** simulated data,experimental results show that the plot profile of the proposed model keeps close to the original one compared to the other ***,it presents a notable gain in terms of contrast to noise ratio(CNR)and execution *** proposed model shows better results in the computation of contrast metric with a value of 0.68±7.2 and the highest signal to noise ratio(SNR)with a value of 78.56±6.4 in real *** experimental results prove that the proposed algorithm is more accurate and robust in reconstructing SPECT images than the other *** could be considered a valuable candidate to correct the resolution of bone in the SPECT images.

关键词： SPECT image resolution correction thoracic SPECT images wavelet transform curvelet transforms 3D-OSEM PDE

Vibrational, Electronic and Structural Study of Sprayed ZnO Thin Film Based on the IR-Raman Spectra and DFT Calculations

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Crystal Structure Theory and Applications 2022年第2期11卷 23-38页

作者： bechir Ouni Tarek Larbi Mosbah Amlouk Unité de Physique des Dispositifs a Semi-Conducteurs Faculté des Sciences de Tunis Tunis El Manar University Tunis Tunisia

Applying the Density Function Theory (DFT) combined with LCAO basis set and employing the B3LYP hybrid functional, the optimized geometrical parameters, electronic properties, as well as the Infrared and Raman spectra for wurtzite-ZnO structure were investigated. Prior to computing, ZnO thin film prepared by the spray pyrolysis method is characterized by X-ray diffraction using Rietveld refinement. This analysis shows that ZnO has hexagonal wurtzite structure (P63mc) with lattice parameters, a = 3.2467 and c = 5.2151 Åin good agreement with our predicted optimized geometry. Atomic force microscopy (AFM), Raman spectroscopy and UV-Vis-NIR spectrophotometry techniques are used to explore morphological, optical and vibrational properties of the sprayed ZnO thin film. The computed band gap is in excellent agreement with that deduced from UV-Vis transmission . The simulated infrared and Raman spectra were also calculated, and a good agreement with the measured spectra is obtained. Finally, a detailed interpretation of the infrared and Raman spectra is reported.

关键词： DFT Thin Film Electronic Structure IR and Raman Spectroscopy

Adult Kidney Cancer in Mauritania: Clinical and Therapeutic Aspects

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Open Journal of Urology 2023年第6期13卷 178-184页

作者： Mohamed Mahmoud Beya Yahya Tfeil Aboubacar Traore Mouhamadou Diagana Mohamed bechir Essalem Sheikh Zayed Hospital Nouakchott Mauritania

Introduction: since its creation, our urology department has taken care of tumor pathologies in particular kidney cancer in adults;our goal is to study the clinical and therapeutic epidemiological profiles of adult kidney cancer in Mauritania. Materials and Methods: We carried out a retrospective study over a period of six years, from January 1, 2012 to December 31, 2017, including all cases of adult kidney cancer registered in the urology-andrology departments of the Cheikh Zayed Hospital and Pathological Anatomy of the National Hospital of Nouakchott (Mauritania). Results: we collected 50 cases of kidney cancer. The average annual incidence was 8.3 cases. The average age of the patients was 52.98 years with extremes of 18 and 84 years. There was a female predominance (52%) or 29 women for 21 men. Lumbar pain was the most frequent clinical expression, more than half of the patients had symptoms over a period of at least 12 months before the first consultation. The left kidney was the most frequently affected. The right localization was demonstrated in 23 patients, the extension assessment was made with thoraco-abdomino-pelvic CT in 40 patients. Twelve patients had a tumor localized in the kidney. The extension assessment had made it possible to objectify the existence of metastases in 17 of our patients (37%). The preferred locations of these metastases were pulmonary and hepatic. Surgical intervention was performed in 44 patients (88%), of whom 36 underwent radical nephrectomy (72%), and two patients underwent partial nephrectomy (4.5%). Surgical abstention was decided from the outset in 6 patients (13.6%). None of our patients had received treatment with anti-angiogenics. The histological type most observed in our patients was renal cell carcinoma, observed in 34 patients, or 77.72%. At the time of the study, more than a third of the patients had died. The mortality rate in our series had reached 24%. A specific survival rate could not be assessed due to lack of

关键词： Adult Kidney Cancer Mauritania Clinical and Therapeutic Epidemiological Profiles

Synthesis of novel adsorbent by intercalation of biopolymer in LDH for the removal of arsenic from synthetic and natural water

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Journal of Environmental Sciences 2020年第5期32卷 246-261页

作者： Hanen Bessaies Sidra Iftekhar Bhairavi Doshi Jamel Kheriji Mohamed Chaker Ncibi Varsha Srivastava Mika Sillanpaa bechir Hamrouni Laboratory of Desalination and Water Treatement LR19ES01 Faculty of Sciences of TunisTunis El Manar University2092El Manar ITunisia Department of Separation Science Lappeenranta-Lahti University of Technology(LUT)Sammonfeatu 12FI-50130MikkeliFinland International Water Research Institute MohammedⅥPolytechnic UniversityCity Ben Guerir 43150Morocco Department of Civil and Environmental Engineering Florida International UniversityMiamiFL 33174USA Department of Environmental Engineering University of Engineering and TechnologyTaxilaPakistan

This study focuses on the synthesis of nanocomposites named CCA and CZA that were prepared by the incorporation of cellulose(CL)in the Ca/Al and Zn/Al layered double hydroxide(LDH),*** materials were then used for the uptake of As(Ⅲ)and As(V)from aqueous *** of both nanocomposites(CCA and CZA)was done using FTIR and Raman analysis to identify the functional groups,N2 adsorption-desorption isotherms to determine the specific surface area and pore geometry and XPS analysis to obtain the surface atomic *** other characters were investigated using simultaneous TGA and DTA and elemental chemical analysis(CHNS/O).The crystallinity of the prepared nanocomposites was displayed by XRD ***,the sheet-like structure of the LDHs and the irregularity of surface morphology with porous structure were observed by TEM and SEM *** of maximum adsorption capacity was adjusted using different parameters including pH,contact time and adsorbent *** pseudo-second-order model was in good fitting with kinetics *** adsorption isotherm results showed that CZA exhibits better adsorption capacity for As(Ⅲ)than CCA and the Langmuir isotherm model described the data well for both *** studies illustrated the endothermic nature of CCA and exothermic nature on CZA,as well as the fact that the adsorption process is spontaneous.A real water sample collected from well located in Gabes(Tunisia),has also been *** obtained experimental results were confirmed that these sorbents are efficient for the treatment of hazardous toxic species such as.

关键词： Layered double hydroxide Adsorption Arsenic removal Kinetics Natural water treatment