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MATHEMATICAL ANALYSIS OF WEST NILE VIRUS MODEL WITH DISCRETE DELAYS

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Acta Mathematica Scientia 2013年第5期33卷 1439-1462页

作者： Salisu M.GARBA mohammad A.safi Department of Mathematics and Applied Mathematics University of Pretoria Department of Mathematics The Hashemite University

The paper presents the basic model for the transmission dynamics of West Nile virus （WNV）. The model, which consists of seven mutually-exclusive compartments representing the birds and vector dynamics, has a locally-asymptotically stable disease- free equilibrium whenever the associated reproduction number （R0） is less than unity. As reveal in [3, 20], the analyses of the model show the existence of the phenomenon of backward bifurcation （where the stable disease-free equilibrium of the model co-exists with a stable endemic equilibrium when the reproduction number of the disease is less than unity）. It is shown, that the backward bifurcation phenomenon can be removed by substituting the associated standard incidence function with a mass action incidence. Analysis of the reproduction number of the model shows that, the disease will persist, whenever R0 〉 1, and increase in the length of incubation period can help reduce WNV burden in the community if a certain threshold quantities, denoted by △b and △v are negative. On the other hand, increasing the length of the incubation period increases disease burden if △b 〉 0 and △v 〉 0. Furthermore, it is shown that adding time delay to the corresponding autonomous model with standard incidence （considered in [2]） does not alter the qualitative dynamics of the autonomous ：system （with respect to the elimination or persistence of the disease）.

关键词： West Nile virus (WNV) equilibria stability persistent reproduction number

A Discrete Model of TB Dynamics in Khyber Pakhtunkhwa-Pakistan

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Computer Modeling in Engineering & Sciences 2020年第5期123卷 777-795页

作者： Muhammad Altaf Khan Khanadan Khan mohammad A.safi Mahmoud H.DarAssi Faculty of Natural and Agricultural Sciences University of the Free StateBloemfonteinSouth Africa Department of Mathematics City University of Science and Information TechnologyPeshawarPakistan Department of Mathematics The Hashemite universityZarqaJordan Department of Basic Sciences Princess Sumaya University for TechnologyAmmanJordan

The present paper investigates the theoretical analysis of the tuberculosis(TB)model in the discrete-time *** model is parameterized by the TB infection cases in the Pakistani province of Khyber Pakhtunkhwa between 2002 and *** model is parameterized and the basic reproduction number is obtained and it is found R_(0)=1:*** stability analysis for the model is presented and it is shown that the discrete-time tuberculosis model is stable at the disease-free equilibrium whenever R_(0)1.A discrete fractional model in the sense of Caputo derivative is *** numerical results of the model with various parameters and their effect on the model are presented.A comparison of discrete-time method with continuous-time model is presented graphically.A discrete fractional approach is compared with the existing method in literature and some reasonable results are ***,a summary of results and conclusion are presented.

关键词： Discrete TB model real data equilibria Lyapunov stability Caputo derivative

Secure Channel Estimation Using Norm Estimation Model for 5G Next Generation Wireless Networks

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Computers, Materials & Continua 2025年第1期82卷 1151-1169页

作者： Khalil Ullah Song Jian Muhammad Naeem Ul Hassan Suliman Khan mohammad Babar Arshad Ahmad Shafiq Ahmad Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Department of Computer Science Abbottabad University of Science and TechnologyHavelianAbbottabad22500Pakistan Department of Computing and Electronics Engineering Middle East CollegeMuscat124Oman Department of CS&IT Pak-Austria Fachhochschule Institute of Applied Sciences and Technology MangHaripur22621Pakistan Industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile *** networks are sufficiently scaled to interconnect billions of users and *** in academia and industry are focusing on technological advancements to achieve highspeed transmission,cell planning,and latency reduction to facilitate emerging applications such as virtual reality,the metaverse,smart cities,smart health,and autonomous *** continuously improves its network functionality to support these *** input multiple output(MIMO)technology offers spectral efficiency,dependability,and overall performance in *** article proposes a secure channel estimation technique in MIMO topology using a norm-estimation model to provide comprehensive insights into protecting NextG network components against adversarial *** technique aims to create long-lasting and secure NextG networks using this extended *** viability of MIMO applications and modern AI-driven methodologies to combat cybersecurity threats are explored in this ***,the proposed model demonstrates high performance in terms of reliability and accuracy,with a 20%reduction in the MalOut-RealOut-Diff metric compared to existing state-of-the-art techniques.

关键词： Next generation networks massive mimo communication network artificial intelligence 5G adversarial attacks channel estimation information security

Engendered nanoparticles for treatment of brain tumors

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Oncology Research 2025年第1期33卷 15-26页

作者： SOROUSH SOLEYMANI mohammad DOROUDIAN MAHDIEH SOEZI ALI BELADI KIARASH ASGARI ASO MOBARAKSHAHI ARYANA AGHAEIPOUR RONAN MACLOUGHLIN Department of Cell and Molecular Biology School of Biological SciencesUniversity of LeicesterLeicesterLE17RHUK Department of Cell and Molecular Biology Faculty of Biological SciencesKharazmi UniversityTehran15719-14911Iran Cancer Epidemiology Research Center Aja University of Medical SciencesTehran14117-18541Iran Medical Biotechnology Research Center Aja University of Medical SciencesTehran14117-18541Iran Department of Life Sciences Faculty of Natural SciencesImperial College LondonLondonSW72AZUK School of Pharmacy and Biomolecular Sciences Royal College of Surgeons in Ireland(RCSI)DublinD02 YN77Ireland Research and Development Science and Emerging TechnologiesAerogen Ltd.Galway Business ParkGalwayH91 HE94Ireland School of Pharmacy and Pharmaceutical Sciences Trinity CollegeDublinD02 PN40Ireland

Brain metastasis and primary glioblastoma multiforme represent the most common and lethal malignant brain *** median survival time is typically less than a year after *** of the major challenges in treating these cancers is the efficiency of the transport of drugs to the central nervous *** blood-brain barrier is cooperating with advanced stages of *** blood-brain barrier poses a significant challenge to delivering systemic medications to brain *** delivery systems have emerged as promising tools for effectively crossing this ***,the development of smart nanoparticles brings new hope for cancer diagnosis and *** nanoparticles improve drug delivery efficiency,allowing for the creation of targeted and stimuli-responsive delivery *** review highlights recent advancements in nanoparticle and smart nanoparticle technologies for brain cancer treatment,exploring the range of nanoparticles under development,their applications,targeting strategies,and the latest progress in enhancing transport across the blood-brain *** also addresses the ongoing challenges and potential benefits of these innovative approaches.

关键词： Nanoparticles Smart nanoparticles Stimuli responsive nanoparticles Targeted nanoparticles Blood-brain barrier(BBB) Brain cancer

Cooperative distributed state estimation:resilient topologies against smart spoofers

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Control Theory and Technology 2022年第4期20卷 488-503页

作者： Mostafa safi Amirkabir University of Technology HafezTehran 424Iran

A network of observers is considered,where through asynchronous(with bounded delay)communications,they cooperatively estimate the states of a linear time-invariant(LTI)*** such a setting,a new type of adversary might affect the observation process by impersonating the identity of the regular node,which is a violation of communication *** adversaries also inherit the capabilities of Byzantine nodes,making them more powerful threats called smart *** show how asynchronous networks are vulnerable to smart spoofing *** the estimation scheme considered in this paper,information flows from the sets of source nodes,which can detect a portion of the state variables each,to the other follower *** regular nodes,to avoid being misguided by the threats,distributively filter the extreme values received from the nodes in their *** conditions based on strong robustness are proposed to guarantee the *** simulation scenarios are provided to verify the results.

关键词： Cyber-physical systems Smart spoofing Distributed resilient algorithm Secure observers

Decoding molecular mechanisms:brain aging and Alzheimer's disease

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Neural Regeneration Research 2025年第8期20卷 2279-2299页

作者： Mahnoor Hayat Rafay Ali Syed Hammad Qaiser mohammad Uzair Khalid Al-Regaiey Roaa Khallaf Lubna Abdullah Mohammed Albassam Imdad Kaleem Xueyi Wang Ran Wang Mehwish SBhatti Shahid Bashir Atta-ur-Rahman School of Applied Biosciences(ASAB) National University of Sciences and Technology(NUST)IslamabadPakistan Department of Biotechnology Quaid-i-Azam UniversityIslamabadPakistan Department of Biological Sciences Faculty of Basic&Applied SciencesInternational Islamic University Islamabad(IIUI)IslamabadPakistan Department of Bioengineering King Fahd University of Petroleum and MineralsDhahranSaudi Arabia Department of Physiology College of MedicineKing Saud UniversityRiyadhSaudi Arabia Department of Neurology Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Mental Health Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Biosciences Commission on Science and Technology for Sustainable Development in the South(COMSATS University)IslamabadPakistan Department of Psychiatry The First Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Mental Health Institute of Hebei Medical University ShijiazhuangHebei ProvinceChina Department of Neurobiology and Behavior University of CaliforniaIrvineCAUSA Neuroscience Center King Fahad Specialist Hospital DammamDammamSaudi Arabia

The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for *** aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's *** these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging *** these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect *** review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease.

关键词： Alzheimer’s disease brain aging cognitive health dementia molecular mechanisms neuronal activity neuroplasticity neurotransmission

Nonlinear Vibration Analysis of Functionally GradedNanobeam Using Homotopy Perturbation Method

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Advances in Applied Mathematics and Mechanics 2017年第1期9卷 144-156页

作者： Majid Ghadiri Mohsen safi Faculty of Engineering Department of MechanicsImam Khomeini International UniversityQazvinIran

In this paper, He’s homotopy perturbation method is utilized to obtainthe analytical solution for the nonlinear natural frequency of functionally gradednanobeam. The functionally graded nanobeam is modeled using the Eringen’s nonlocalelasticity theory based on Euler-Bernoulli beam theory with von Karman nonlinearityrelation. The boundary conditions of problem are considered with both sidessimply supported and simply supported-clamped. The Galerkin’s method is utilizedto decrease the nonlinear partial differential equation to a nonlinear second-order ordinarydifferential equation. Based on numerical results, homotopy perturbationmethodconvergence is illustrated. According to obtained results, it is seen that the second termof the homotopy perturbation method gives extremely precise solution.

关键词： Homotopy perturbation method Lindstedt-Poincare method analytical solution nonlocal nonlinear free vibration functionally graded nanobeam

SRResNet Performance Enhancement Using Patch Inputs and Partial Convolution-Based Padding

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Computers, Materials & Continua 2023年第2期74卷 2999-3014页

作者： safi Ullah Seong-Ho Song Division of Software Hallym University1 Hallymdaehak-gilChuncheonGangwon-doKorea Department of Information Technology University of GujratJalalpur Jattan RoadGujratPakistan

Due to highly underdetermined nature of Single Image Super-Resolution(SISR)problem,deep learning neural networks are required to be more deeper to solve the problem *** of deep neural networks successful in the Super-Resolution(SR)problem is ResNet which can render the capability of deeper networks with the help of skip ***,zero padding(ZP)scheme in the network restricts benefits of skip connections in SRResNet and its performance as the ratio of the number of pure input data to that of zero padded data *** this *** consider the ResNet with Partial Convolution based Padding(PCP)instead of ZP to solve SR *** training of deep neural networks using patch images is advantageous in many aspects such as the number of training image data and network complexities,patch image based SR performance is compared with single full image based *** experimental results show that patch based SRResNet SR results are better than single full image based ones and the performance of deep SRResNet with PCP is better than the one with ZP.

关键词： Single image super-resolution SRResNet patch inputs zero padding partial convolution based padding

Risk factors for congenital nasolacrimal duct obstruction in children under two years of age

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国际眼科杂志 2025年第1期25卷 17-23页

作者： Rozhin Kasiri Gholamreza Khataminia Ali Kasiri mohammad Sadegh Mirdehghan mohammad Armin Kasiri Infectious Ophthalmologic Research Center Ahvaz Jundishapur University of Medical SciencesAhvaz ***Iran Islamic Azad University Tehran Medical Sciences Tehran ***Iran

·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case group of 122 children less than two years of age with CNLDO who underwent probing and irrigation treatment at the ophthalmology department of Imam Khomeini Hospital in Ahvaz,Iran,from June 2022 to June2024.A control group of 122 age-matched children without CNLDO was also included for *** was collected from the children's medical records.·RESULTS:The study found a significant correlation between the occurrence of CNLDO and several maternal factors,such as preeclampsia,the use of levothyroxine,hypothyroidism,having more than three pregnancies(gravidity>3),natural pregnancy,and gestational diabetes ***,in children,factors,such as oxygen therapy,anemia,reflux,jaundice,and a family history of CNLDO in first-degree relatives were associated with CNLDO,and maternal preeclampsia and hypothyroidism were found to significantly increase the risk of developing CNLDO in children.·CONCLUSION:Given that CNLDO affects both premature and full-term children,the present findings may potentially facilitate the early identification of children and infants at risk of nasolacrimal duct obstruction,thereby preventing the onset of chronic dacryocystitis.

关键词： risk factors congenital nasolacrimal duct obstruction children