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Dynamical Behaviors of Nonlinear Coronavirus (COVID-19) model with Numerical studies

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Computers, materials & Continua 2021年第4期67卷 675-686页

作者： Khaled A.Gepreel mohamed s.mohamed Hammad Alotaibi amr m.s.mahdy Department of mathematics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of mathematics Zagazig UniversityZagazig44519Egypt Department of mathematics Al-Azher UniversityNasr City11884Egypt

The development of mathematical modeling of infectious diseases is a key research area in various elds including ecology and *** aim of these models is to understand the dynamics of behavior in infectious *** the new strain of coronavirus(COVID-19),there is no vaccine to protect people and to prevent its spread so ***,control strategies associated with health care,such as social distancing,quarantine,travel restrictions,can be adopted to control the pandemic of *** article sheds light on the dynamical behaviors of nonlinear COVID-19 models based on two methods:the homotopy perturbation method(HPm)and the modied reduced differential transform method(mRDTm).We invoke a novel signal ow graph that is used to describe the COVID-19 *** our mathematical studies,it is revealed that social distancing between potentially infected individuals who are carrying the virus and healthy individuals can decrease or interrupt the spread of the *** numerical simulation results are in reasonable agreement with the study *** free equilibrium and stability point for the COVID-19 model are ***,the existence of a uniformly stable solution is proved.

关键词： Nonlinear COVID-19 model equilibrium point stability existence of uniformly stable signal ow graph homotopy perturbation method reduced differential transform method

An Approximate Numerical methods for mathematical and Physical studies for Covid-19 models

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Computer systems science & Engineering 2022年第9期42卷 1147-1163页

作者： Hammad Alotaibi Khaled A.Gepreel mohamed s.mohamed amr m.s.mahdy Department of mathematics College of ScienceTaif UniversityTaif21944Saudi Arabia

The advancement in numerical models of serious resistant illnesses is a key research territory in different fields including the nature and the study of disease *** of the aims of these models is to comprehend the elements of conduction of these *** the new strain of Covid-19(Coronavirus),there has been no immunization to protect individuals from the virus and to forestall its spread so *** things being equal,control procedures related to medical services,for example,social distancing or separation,isolation,and travel limitations can be adjusted to control this *** article reveals some insights into the dynamic practices of nonlinear Coronavirus models dependent on the homotopy annoyance strategy(HPm).We summon a novel sign stream chart that is utilized to depict the Coronavirus *** the numerical investigations,it is uncovered that social separation of the possibly tainted people who might be conveying the infection and the healthy virus-free people can diminish or interrupt the spread of the *** mathematical simulation results are highly concurrent with the statistical *** free balance and dependability focus for the Coronavirus model is discussed and the presence of a consistently steady arrangement is demonstrated.

关键词： Covid-19 model optimal control existence of uniformly stable signal stream chart homotopy perturbation technique

Describe the mathematical model for Exchanging Waves Between Bacterial and Cellular DNA

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Computers, materials & Continua 2021年第9期68卷 3615-3628页

作者： mohamed s.mohamed sayed K.Elagan saad J.Almalki muteb R.Alharthi mohamed F.El-Badawy amr m.s.mahdy Department of mathematics College of ScienceTaif UniversityTaif21944Saudi Arabia microbiology and immunology Department Faculty of PharmacyUniversity of Sadat CityMenoufiya GovernorateEgypt

In this article,we have shown that bacterial DNA could act like some coils which interact with coil-like DNA of host *** decreasing the separating distance between two bacterial cellular DNA,the interaction potential,entropy,and the number of microstates of the system ***,the system gives its energy to the medium and the temperature of the host body *** could be seen as fever in *** emitting some special waves and changing the temperature of the medium,the effects of bacterial waves could be reduced and bacterial diseases could be *** investigators have shown that bacterial DNA could emit or absorb electromagnetic *** of the main experiments about bacterial waves has been done by montagnier and his *** have shown that the genomic DNA of most pathogenic bacteria includes sequences that are able to emit electromagnetic *** results have shown that wave affects the crucial physicochemical processes in both Gram-positive and Gram-negative *** emphasis in this survey is on the development of controlling model equations and computer emulation of the model equations rather than on mathematical methods for solving the model equations and differential equations of epidemics.

关键词： DNA bacteria diseases inductor magnetic field

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa m.G.Cassiano Roney s.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Numerical studies for solving fractional integro-differential equations

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Journal of Ocean Engineering and science 2018年第2期3卷 127-132页

作者： A.m.s.mahdy Department of mathematics Faculty of ScienceZagazig UniversityZagazigEgypt Department of mathematics Faculty of ScienceTaif UniversitySaudi Arabia

In this paper,we give a new numerical method for solving a linear system of fractional integro-differential *** fractional derivative is considered in the Caputo *** proposed method is least squares method aid of Hermite *** suggested method reduces this type of systems to the solution of systems of linear algebraic *** demonstrate the accuracy and applicability of the presented method some test examples are *** results show that this approach is easy to implement and accurate when applied to integro-differential *** show that the solutions approach to classical solutions as the order of the fractional derivatives approach.

关键词： Least squares method Caputo fractional Hermite polynomials Linear fractional integro-differential equations

soil Properties and Wheat Growth and Nutrients as Affected by Compost Amendment Under saline Water Irrigation

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Pedosphere 2011年第6期21卷 773-781页

作者： A.m.mahdy Department of soil and Water College of Agriculture(Elshatby)Alexandria University

A greenhouse experiment was conducted to test and compare the suitability of saline compost and saline irrigation water for nutrient status amendment of a slightly productive sandy clay loam soil, to study the macronutrient utilization and dry matter production of wheat （Triticum aestivum c.v. Gemmiza 7） grown in a modified soil environment and to determine the effects of compost and saline irrigation water on soil productivity. The sandy clay loam soil was treated with compost of five rates （0, 24, 36, 48, and 60 m3 ha-1, equivalent to 0, 3, 4.5, and 6 g kg-1 soil, respectively） and irrigation water of four salinity levels （0.50 （tap water）, 4.9, 6.3, and 8.7 ds m-l）. The results indicated that at harvest, the electrical conductivity （EC） of the soil was significantly （P 〈 0.05） changed by the compost application as compared to the control. In general, the soil salinity significantly increased with increasing application rates of compost. soluble salts, K, C1, HCO3, Na, Ca, and mg, were significantly increased by the compost treatment. soil sodium adsorption ratio （sAR） was significantly affected by the salinity levels of the irrigation water, and showed a slight response to the compost application. The soil organic carbon content was also significantly （P 〈 0.05） affected by application of compost, with a maximum value of 31.03 g kg-1 recorded at the compost rate of 60 m3 ha-1 and the irrigation water salinity level of 8.7 ds m-1 and a minimum value of 12.05 g kg-1 observed in the control. The compost application produced remarkable increases in wheat shoot dry matter production. The maximum dry matter production （75.11 g pot-1） occurred with 60 ma ha-1 compost and normal irrigation water, with a minimum of 19.83 g pot-1 with no addition of compost and irrigation water at a salinity level of 8.70 ds m-1. significant increases in wheat shoot contents of K, N, P, Na, and C1 were observed with addition of compost. The relatively high shoot N values may be attributed

关键词： electrical conductivity plant dry matter soil organic C soil sodium adsorption ratio soluble salts

Predicting maximum Lifespan Limits at mean menopausal Age

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Journal of mathematical Research with Applications 2025年第1期 133-142页

作者： m.sUmATHI s.ANTONY CARLA Department of mathematics N.M.S.S.Vellaichamy Nadar College Research scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

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macroscopic studies on the Properties of the Anodic Oxide Films on Titanium

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Journal of materials science & Technology 1998年第3期14卷 241-246页

作者： mahdy, G.A. mahmoud, s.s. Chemistry Dept. Faculty of Science Helwan University Helwan Cairo Egypt Chemistry Dept. University College for Women Ain-Shams University Helopolis Cairo Egypt

The effect of fluoride ions on the formation and dissolution behaviour of anodic oxide films on Ti has been investigated in acidic fluoride media (pH=1) using impedance and galvanostatic techniques. A5 the fluoride ion concentration and temperature increase the rate of oxide film formation decreases while the dissolution process increases. oxide film formed at high tem-perature and formation voltage was found to contain more defect sites in the film than that formed at a lower one. Activation energies are calculated during the oxide film formation and dissolution and found to be 20.76 and 28.72 kJ/mol, respectively. Formation rate and reciprocal capacitance data are reported as a function of polarizing current density. Values are recorded for the electrolytic parameters A and B. Potentiostatic curves are derived from the galvanostatic results.

关键词： Figure macroscopic studies on the Properties of the Anodic Oxide Films on Titanium

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-mañé Laia Just-Borràs marta Balanyà-segura Aleksandra Polishchuk Laura Nadal marta Tomàs Carolina silvera-simón manel m.santafé maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB