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A Radial Basis Function Method with Improved Accuracy for Fourth Order Boundary Value Problems

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Journal of Applied Mathematics and Physics 2024年第7期12卷 2559-2573页

作者： Scott A. sarra Derek Musgrave Marcus Stone Joseph I. Powell Department of Mathematics Marshall University Huntington WV USA

Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with Radial Basis Function methods. The method is used to solve fourth order boundary value problems. The use and location of ghost points are examined in order to enforce the extra boundary conditions that are necessary to make a fourth-order problem well posed. The use of ghost points versus solving an overdetermined linear system via least squares is studied. For a general fourth-order boundary value problem, the recommended approach is to either use one of two novel sets of ghost centers introduced here or else to use a least squares approach. When using either ghost centers or least squares, the random variable shape parameter strategy results in significantly better accuracy than when a constant shape parameter is used.

关键词： Numerical Partial Differential Equations Boundary Value Problems Radial Basis Function Methods Ghost Points Variable Shape Parameter Least Squares

A Comparative Analysis on Surgical Outcomes and Complications of Endoscopic and Open Vein Harvesting Techniques

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Open Journal of Thoracic Surgery 2024年第2期14卷 29-39页

作者： Mohammed Fawzy Eltaweel Ismail N. El-Sokkary Ahmed Alherazi Mohamed Wael Badawi Mohammed G. Abdellatif Bahaa A. Elkhonezy Ibrahim K. Gamil Haytham Mohamed Abd El Moaty sarra Sadmi Mahmoud Khalil Department of Cardiothoracic Surgery Faculty of Medicine Menoufia University Shibin El Kom Egypt Department of Cardiovascular & Thoracic Surgery Faculty of Medicine Al-Azhar University Cairo Egypt Department of Cardiothoracic Surgery Faculty of Medicine Alexandria University Alexandria Egypt Faculty of Medicine University of Algiers Algiers Algeria Department of Cardiac Surgery Sabah Al-Ahmed Cardiac Center Al-Amiri Hospital Kuwait City Kuwait

Objective: The great saphenous vein (GSV) is commonly used as a conduit for grafting during CABG surgery, and open GSV harvesting (OVH), commonly used with long incision to expose the vein. However, endoscopic vein harvesting (EVH) is an alternative approach, utilizing specialized instruments and small incisions to harvest the vein. Methods: A retrospective analysis was conducted on a cohort of patients who underwent Coronary artery bypass graft (CABG) requiring great saphenous vein (GSV) harvesting which was done by EVH or OVH procedures. Demographic variables, including age and gender, were assessed for both groups. Intraoperative variables such as the number of grafts, cardiopulmonary bypass time, X clamp time, and type of procedure were analyzed. Postoperative variables, including infection and bleeding rates, were also evaluated. Results: The study included 30 patients each undergoing Coronary artery bypass graft (CABG) with need of great saphenous vein harvesting which was done by EVH and OVH. Demographic variables were well-matched between the two groups in terms of age, while a significant difference in gender distribution was observed. Obesity and smoking were more prevalent in the OVH group, and EVH was associated with a higher mean number of grafts compared to OVH. Conversion to an open technique occurred in a portion of the EVH cases, and infection rates did not significantly differ between the EVH and OVH groups. However, the incidence of postoperative bleeding was significantly higher in the EVH group. Conclusion: This study provides valuable insights into the demographic, intraoperative, and postoperative variables associated with EVH and OVH techniques. EVH demonstrated advantages in terms of reduced infection rates compared to OVH. However, the higher incidence of postoperative bleeding associated with EVH raises concerns about potential risks.

关键词： Endoscopic Vein Harvesting (EVH) Open Vein Harvesting (OVH) Coronary Artery Bypass Grafting (CABG) Great Saphenous Vein (GSV) Surgical Outcomes

Effect of an Inclined Slots on the Power Consumption and Vortices Size in a Rushton Turbine Agitated Tank

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 261-276页

作者： sarra Youcefi Mohamed Bouzit Abdelkader Youcefi Abderrahim Mokhefi Laboratory of Applied Mechanics Department of Mechanical EngineeringUniversity of Sciences and Technology of OranOran 31000Algeria Laboratory of Maritime Sciences and Engineering Department of Marine EngineeringUniversity of Science and Technology of OranOran 31000Algeria Laboratory of Aeronautics and Propulsion Systems Department of Mechanical EngineeringUniversity of Science and Technology of OranOran 31000Algeria Laboratory of Mechanics Modeling and ExperimentationDepartment of Mechanical EngineeringTahri Mohamed University of BecharBechar 08000Algeria

Mechanical agitation in baffled vessels with turbines plays a vital role in achieving homogeneous fluid mixing and promoting various transfer ***,designing vessels with optimal energy efficiency and flow dynamics is essential to enhance operational performance and eliminate flow ***,the present research focuses on a numerical investigation of the impact of inclined slots with different angles installed at the side-wall of a cylindrical vessel equipped with a Rushton *** study explores power consumption and vortex size while considering various rotation directions of the impeller with different rotation *** numerical simulations are conducted for Reynolds numbers ranging from 104 to 105,using the RANS k-εturbulence model to govern the flow inside the stirred vessel,accounting for mass and momentum *** results have shown that the installation of slots reduces power consumption and vortex size compared to conventional vessel ***,increasing the slot angle from 0 to 32.5°further reduces energy consumption and vortex size,especially with negative rotation *** the other hand,increasing the Reynolds numbers leads to a decrease in power consumption and an increase in vortex *** present research therefore proposes a design for con-structing Rushton-turbine stirred vessels offering optimal operation,characterized by reduced energy consumption and minimized vortex size.

关键词： Mixing Stirred tank Rushton turbine Inclined slots Hydrodynamic Power consumption Vortices size

Trends in insulin resistance:insights into mechanisms and therapeutic strategy

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Signal Transduction and Targeted Therapy 2022年第8期7卷 2762-2786页

作者： Mengwei Li Xiaowei Chi Ying Wang sarra Setrerrahmane Wenwei Xie Hanmei Xu The Engineering Research Center of Synthetic Peptide Drug Discovery and Evaluation of Jiangsu Province China Pharmaceutical UniversityNanjing 210009China State Key Laboratory of Natural Medicines Ministry of EducationChina Pharmaceutical UniversityNanjing 210009China Development Center for Medical Science&Technology National Health Commission of the People’s Republic of China 100044 BeijingChina NANJING ANJI BIOTECHNOLOGY CO.LTD Nanjing 210033China

The centenary of insulin discovery represents an important opportunity to transform diabetes from a fatal diagnosis into a medically manageable chronic *** is a key peptide hormone and mediates the systemic glucose metabolism in different *** resistance(IR)is a disordered biological response for insulin stimulation through the disruption of different molecular pathways in target *** conditions and genetic factors have been implicated in *** genetic and biochemical studies suggest that the dysregulated metabolic mediators released by adipose tissue including adipokines,cytokines,chemokines,excess lipids and toxic lipid metabolites promote IR in other *** is associated with several groups of abnormal syndromes that include obesity,diabetes,metabolic dysfunction-associated fatty liver disease(MAFLD),cardiovascular disease,polycystic ovary syndrome(PCOS),and other *** no medication is specifically approved to treat IR,we summarized the lifestyle changes and pharmacological medications that have been used as efficient intervention to improve insulin ***,the systematic discussion of complex mechanism will help to identify potential new targets and treat the closely associated metabolic syndrome of IR.

关键词： metabolism stimulation diagnosis

Potential risk of soil irrigation with treated wastewater over 40 years:a field experiment under semi-arid conditions in northeastern Tunisia

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Journal of Arid Land 2023年第4期15卷 407-423页

作者： sarra HECHMI Samira MELKI Mohamed-Naceur KHELIL Rim GHRIB Moncef GUEDDARI Naceur JEDIDI Water Research and Technology Center University of CarthageSoliman 8020Tunisia National Institute for Research in Rural Engineering Water and ForestryAriana 2080Tunisia Faculty of Sciences of Tunis University of Tunis El ManarTunis 2092Tunisia

In Tunisia,water scarcity is only adding pressure on water demand in *** the context of sustainable development goals,Tunisia has been reusing treated wastewater(TWW)as a renewable and inexpensive source for soil fertigation and groundwater(GW)***,major risks can be expected when the irrigation water is of poor *** study aims for evaluating the potential risk of TWW and GW irrigation on soil ***,we evaluated the suitability of water quality through the analysis of major and minor cations and anions,metallic trace elements(MTEs),and the sodium hazard by using the sodium adsorption ratio(SAR)and the soluble sodium percentage(SSP).The risk of soil sodicity was further assessed by SAR and the exchangeable sodium percentage(ESP).The degree of soil pollution caused by MTEs accumulation was evaluated using geoaccumulation index(Igeo)and pollution load index(PLI).Soil maps were generated using inverse spline interpolation in ArcGIS *** results show that both water samples(i.e.,TWW and GW)are suitable for soil irrigation in terms of salinity(electrical conductivity5.00),followed by Ni^(2+)and Pb^(2+).Nevertheless,Cd^(2+)presents the lowest risk of soil pollution(Igeo50.0%).This study shows that the use of imagery tools,such as ArcGIS,can

关键词： treated wastewater metallic trace elements(MTEs) pollution indices sodium adsorption ratio(SAR) geoaccumulation index(Igeo) Tunisia

Smart MobiNet:A Deep Learning Approach for Accurate Skin Cancer Diagnosis

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Computers, Materials & Continua 2023年第12期77卷 3533-3549页

作者： Muhammad Suleman Faizan Ullah Ghadah Aldehim Dilawar Shah Mohammad Abrar Asma Irshad sarra Ayouni Department of Computer Science Bacha Khan UniversityCharsaddaPakistan Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Faculty of Computer Studies Arab Open UniversityMuscatOman School of Biochemistry and Biotechnology University of the PunjabLahorePakistan

The early detection of skin cancer,particularly melanoma,presents a substantial risk to human *** study aims to examine the necessity of implementing efficient early detection systems through the utilization of deep learning ***,the existing methods exhibit certain constraints in terms of accessibility,diagnostic precision,data availability,and *** address these obstacles,we put out a lightweight model known as Smart MobiNet,which is derived from MobileNet and incorporates additional distinctive *** model utilizes a multi-scale feature extraction methodology by using various convolutional *** ISIC 2019 dataset,sourced from the International Skin Imaging Collaboration,is employed in this *** data augmentation approaches are implemented to address the issue of model *** this study,we conduct experiments to evaluate and compare the performance of three different models,namely CNN,MobileNet,and Smart MobiNet,in the task of skin cancer *** findings of our study indicate that the proposed model outperforms other architectures,achieving an accuracy of ***,the model exhibits balanced precision,sensitivity,and F1 scores,all measuring at *** model serves as a vital instrument that assists clinicians efficiently and precisely detecting skin cancer.

关键词： Deep learning Smart MobiNet machine learning skin lesion melanoma skin cancer classification

Local Radial Basis Function Methods: Comparison, Improvements, and Implementation

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Journal of Applied Mathematics and Physics 2023年第12期11卷 3867-3886页

作者： Scott A. sarra Department of Mathematics Marshall University Huntington USA

Radial Basis Function methods for scattered data interpolation and for the numerical solution of PDEs were originally implemented in a global manner. Subsequently, it was realized that the methods could be implemented more efficiently in a local manner and that the local approaches could match or even surpass the accuracy of the global implementations. In this work, three localization approaches are compared: a local RBF method, a partition of unity method, and a recently introduced modified partition of unity method. A simple shape parameter selection method is introduced and the application of artificial viscosity to stabilize each of the local methods when approximating time-dependent PDEs is reviewed. Additionally, a new type of quasi-random center is introduced which may be better choices than other quasi-random points that are commonly used with RBF methods. All the results within the manuscript are reproducible as they are included as examples in the freely available Python Radial Basis Function Toolbox.

关键词： Radial Basis Functions Shape Parameter Selection Quasi-Random Centers Numerical PDEs Scientific Computing Open Source Software Python Programming Language Reproducible Research

Centranthera grandiflore alleviates alcohol-induced oxidative stress and cell apoptosis

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Chinese Journal of Natural Medicines 2022年第8期20卷 572-579页

作者： GAO Xin-Mei DONG Wen-Han XIA Chun-Lei MA Zhuo-Yi WANG Ying sarra Setrerrahmane XU Han-Mei QI Wei-Yan The Engineering Research Center of Synthetic Peptide Drug Discovery and Evaluation Jiangsu ProvinceState Key Laboratory of Natural MedicinesMinistry of EducationDepartment of Marine PharmacyChina Pharmaceutical UniversityNanjing 211198China Science and Technology Administration Department of Yunnan Agricultural University Yunnan 650205China Nanjing Anji Biotechnology Co. Ltd.Nanjing 210033China

Alcohol liver disease(ALD)has become a global threat to human *** is associated with a wide range of liver diseases including alcohol fatty liver,steatosis,fibrosis and cirrhosis,and finally leads to liver cancer and even *** grandiflora is a traditional Chinese medicinal herb commonly used to treat ALD,but no research about its mechanism is *** study evaluated the hepatoprotective effect and mechanism of *** against alcohol-induced liver injury in *** found that the ethanol extracts of ***(CgW)alleviated the alcohol-induced liver injury,enhanced the levels of antioxidant enzymes,and reduced the amount of lipid *** also affected cell apoptosis by inhibiting the activity of Bax,cleaved-caspase 3 and cleaved-caspase 9,and increasing the activity of *** conclusion,the results showed that CgW can effectively improve ALD through alleviating oxidative stress and inhibiting cell apoptosis for the first *** study suggested that *** is a promising herbal medicine for ALD treatment.

关键词： Centranthera grandiflora Alcohol liver diseases Oxidative stress Apoptosis Hepatoprotective effect

A Filtered Milne-Simpson ODE Method with Enhanced Stability Properties

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Journal of Applied Mathematics and Physics 2023年第1期11卷 192-208页

作者： Ari Aluthge Scott A. sarra Marshall University Huntington WV USA

The Milne-Simpson method is a two-step implicit linear multistep method for the numerical solution of ODEs that obtains the theoretically highest order of convergence for such a method. The stability region of the method is only an interval on the imaginary axis and the method is classified as weakly stable which causes non-physical oscillations to appear in numerical solutions. For this reason, the method is seldom used in applications. This work examines filtering techniques that improve the stability properties of the Milne-Simpson method while retaining its fourth-order convergence rate. The resulting filtered Milne-Simpson method is attractive as a method of lines integrator of linear time-dependent partial differential equations.

关键词： Ordinary Differential Equations Numerical Methods Weak Instability