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SIrS epidemic modeling using fractional-ordered differential equations:role of fear effect

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International Journal of Biomathematics 2024年第5期17卷 79-100页

作者： Shiv Mangal O.p.Misra Joydip dhar School of Mathematics and Allied Sciences Jiwaji University GwaliorMadhya PradeshIndia Dep.r.ment of Mathematics Post Graduate College BinaMadhya PradeshIndia Dep.r.ment of Applied Sciences Atal Bihari Vajpayee-Indian Institute of Information Technology and Management GwaliorMadhya PradeshIndia

In this pap.r.an SIrS epidemic model using Grunwald-Letnikov fractional-order derivative is formulated with the help of a nonlinear system of fractional differential equations to analyze the effects of fear in the population during the outbreak of deadly infectious *** criteria for the spread or extinction of the disease are derived and discussed on the basis of the basic reproduction *** condition for the existence of Hopf bifurcation is discussed considering fractional order as a bifurcation ***,using the Grunwald-Letnikov ap.r.ximation,the simulation is carried out to confirm the validity of analytic results *** the real data of COVID-19 in India recorded during the second wave from 15 May 2021 to 15 December 2021,we estimate the model p.r.meters and find that the fractional-order model gives the closer forecast of the disease than the classical *** the analytical results and numerical simulations presented in this study suggest different policies for controlling or eradicating many infectious diseases.

关键词： SIrS epidemic model fear effect Mittag-Leffler function Hopf bifurcation p.r.meter estimation

First Born Double Differential Cross-Section for Ionization of H (3d) by Incident Electron Impact

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Open Journal of Microphysics 2024年第2期14卷 67-77页

作者： Sushmita Banerjee Sunil dhar Dep.r.ment of Mathematics Chittagong University of Engineering and Technology Chittagong Bangladesh

Double differential cross section (DDCS) of First-Born ap.r.ximation is calcu-lated for the ionization of metastable 3d-state hydrogen atoms by electron impact energy at 150 eV and 250 eV. A multiple scattering theory is applied in the present study. The present results are comp.r.d with the other related the-oretical results for the ionization of hydrogen atoms from different metastable states and ground-state exp.r.mental results. The findings demonstrate a strong qualitative agreement with the existing results. The obtained results have an extensive scope for further study of such an ionization process.

关键词： Electron Ionization Cross-Section Scattering

Severe acute resp.r.tory syndrome-coronavirus-2(SArS-COV-2)infection of pneumocytes with vaccination and drug therapy:Mathematical analysis and optimal control

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International Journal of Biomathematics 2024年第2期17卷 299-334页

作者： r.Viriyapong p.Inkhao Dep.r.ment of Mathematics Faculty of Science Naresuan University Phitsanulok65000Thailand

We propose a mathematical model studying a within-host infection dynamics of SArSCoV-2 in *** model incorp.r.tes immune response,vaccination and antiviral *** crucial prop.r.ies of the model-the existence,positivity and boundary of solutions are *** points and the basic reproduction number are *** stability of each equilibrium point is *** control is applied to the model by adding three control variables:vaccination,treatment by Favip.r.vir and treatment by *** results show that each individual control could reduce SArS-CoV-2 infection in some aspects;however,with a combination of three controls,we obtain the best results in reducing SArS-CoV-2 *** study has emphasized the imp.r.ance of prevention by vaccine and the antiviral treatments.

关键词： SArS-CoV-2 vaccination drug therapy immune response optimal control

Galerkin-Bernstein Ap.r.ximations for the System of Third-Order Nonlinear Boundary Value problems

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Journal of Applied Mathematics and physics 2024年第6期12卷 2083-2101页

作者： Snigdha dhar Md. Shafiqul Islam Dep.r.ment of Applied Mathematics University of Dhaka Dhaka Bangladesh

This pap.r.is devoted to find the numerical solutions of one dimensional general nonlinear system of third-order boundary value problems (BVps) for the pair of functions using Galerkin weighted residual method. We derive mathematical formulations in matrix form, in detail, by exploiting Bernstein polynomials as basis functions. A reasonable accuracy is found when the proposed method is used on few examples. At the end of the study, a comp.r.son is made between the ap.r.ximate and exact solutions, and also with the solutions of the existing methods. Our results converge monotonically to the exact solutions. In addition, we show that the derived formulations may be applicable by reducing higher order complicated BVp into a lower order system of BVps, and the p.r.ormance of the numerical solutions is satisfactory. .

关键词： System of Third-Order BVp Galerkin Method Bernstein polynomials Nonlinear BVp Higher-Order BVp

Temp.r.ture-dependent thermal conductivity and fuel p.r.ormance of UN-UO_(2) and UN-X-UO_(2)(X=Mo,W)composite nuclear fuels by finite element modeling

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Journal of Materiomics 2024年第4期10卷 937-946页

作者： Faris Sweidan Diogo ribeiro Costa Huan Liu p.r.Olsson KTH royal Institute of Technology Nuclear EngineeringStockholm10691Sweden Westinghouse Electric Sweden AB Västerås72163Sweden

The temp.r.ture-dependent effective thermal conductivity of UN-X-UO_(2)(X=Mo,W)nuclear fuel composite was *** the exp.r.mental design,the thermal conductivity was calculated using Finite Element Modeling(FEM),and comp.r.d with analytical models for 10%,30%,50%,and 70%(in mass)uncoated/coated UN microspheres in a UO2 *** FEM results show an increase in the fuel thermal conductivity as the mass fraction of the UN microspheres increases from 1.2 to 4.6 times the UO2 reference at 2,000 *** results from analytical models agree with the thermal conductivity estimated by *** results also show that Mo and W coatings have similar thermal behaviors,and the coating thickness influences the thermal conductivity of the *** higher weight fractions,the thermal conductivity of the fuel composite at room temp.r.ture is substantially influenced by the high thermal conductivity coatings ap.r.aching that of ***,the thermal conductivity from FEM was used in the fuel thermal p.r.ormance evaluation during LWr normal op.r.tion to calculate the maximum centerline *** results show a significant decrease in the fuel maximum centerline temp.r.ture ranging from−94 K for 10% UN to−414 K for 70%(in mass)UN comp.r.d to UO2 under the same op.r.ting conditions.

关键词： Accident tolerant fuel UN-X-UO_(2) Composite nuclear fuel Thermal conductivity Finite element modeling Thermal p.r.ormance

Chronic social defeat stress‑induced depression reduces BCG efficacy by promoting regulatory T‑cell levels in mice

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Animal Diseases 2024年第2期4卷 115-126页

作者： rohit Tyagi Xi Chen Atika dhar Bing Yang Wei Zhou Aikebaier reheman Yingying Lei Gang Cao National Key Laboratory of Agricultural Microbiology College of Veterinary MedicineHuazhong Agricultural UniversityWuhan 430070China National Institute of Immunology New Delhi 110067India College of Animal Science and Technology Tarim UniversityAlar 843300China Bio‑Medical Center Huazhong Agricultural UniversityWuhan 430070China

Despite the initial successes of the Bacillus Calmette-Guerin(BCG)vaccine in children,its efficacy against tuberculosis is highly *** is a lack of understanding about how mental conditions influence BCG ***,we used the chronic social defeat stress(CSDS)model to explore the effects of depression on BCG vaccination *** observed higher lung and spleen bacterial loads and a lower organ index in depressed comp.r.d to BCG ***,a relatively lower T cell protective efficacy was observed in both comp.r.d to control and BCG mice via a mycobacterium growth inhibition assay(MGIA).Cytokine expression of IL-12p40,IL-1β,IL-17,TNF-αand IFN-γwas reduced,whereas the expression of IL-10 and IL-5 was increased in the spleen of both comp.r.d to BCG ***,the prop.r.ions of CD4^(+)IFN-γ^(+),CD8^(+)IFN-γ^(+)T lymphocytes and CD4^(+)effector/central memory T cells were reduced in the splenocytes of the depressed BCG *** promotes CD4^(+)regulatory T cells(Treg)and myeloid-derived sup.r.ssor cell(MDSC)generation in depressed mice,contributing to the reduced pro-inflammatory immune response upon BCG *** study provides insight into the decreased protective immunity by BCG vaccination attributable to depression in mice.

关键词： BCG Vaccine efficacy Treg Immune sup.r.ssion Depression

Stability Analysis of DC Microgrid Clusters Based on Step-by-step System Matrix Building Algorithm

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Journal of Modern power Systems and Clean Energy 2024年第3期12卷 900-912页

作者： K.Jithin N.Mayadevi r.Hari Kumar V.p.Mini the Dep.r.ment of Electrical Engineering College of Engineering TrivandrumAPJ Abdul Kalam Technological University(APJAKTU)ThiruvananthapuramIndia

DC microgrids(DCMGs)are made up of a network of sources and loads that are connected by a number of power electronic converters(pECs).The increase in the number of these pECs instigates major concerns in system *** interconnecting the microgrids to form a cluster,the system stability must be *** pap.r.proposes a novel stepby-step system matrix building(SMB)algorithm to update the system matrix of an existing DCMG cluster when a new microgrid is added to the cluster through a distribution *** stability of the individual DCMGs and the DCMG cluster is analyzed using the eigenvalue ***,the p.r.icle swarm optimization(pSO)algorithm is used to retune the controller gains if the newly formed cluster is not *** simulation of the DCMG cluster is carried out in MATLAB/Simulink environment to test the proposed *** results are also validated using the Op4510 real-time simulator(rTS).

关键词： Converter DC microgrid cluster eigenvalue interconnection p.r.icle swarm optimization system stability system matrix

Convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

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Geoscience Frontiers 2024年第3期15卷 119-136页

作者： Allen p.Nutman Clark r.L.Friend Vickie C.Bennett School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the Eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal p.r.dotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;rollinson,2007;van de Löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-Nb systematics,high Th/Yb,Ba/Nb,Ba/Yb ratios and negative Nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upp.r.***,the majority of these samples have Ba/Nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,pearce and Stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/Nb and Ba/Yb signatures reflect lower surficial Ba in Eoarchean oceanic settings,or(ii)in direct comp.r.son with phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upp.r.mantle with lower and upp.r.crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional Eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if op.r.tive,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： Eoarchean Fluid-fluxing plate tectonics Suprasubduction Crustal evolution

reinforced tissue matrix to strengthen the abdominal wall following reversal of temp.r.ry ostomies or to treat incisional hernias

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 823-832页

作者： Spencer p Lake Corey r Deeken Amit K Agarwal Mechanical Engineering&Materials Science Washington University in St.LouisSt.LouisMO 63130United States Covalent Bio LLCSt.LouisMO 63025United States Dep.r.ment of Surgery McGovern Medical School at UTHealthHoustonTX 77026United States

BACKGrOUND Abdominal wall deficiencies or weakness are a common complication of tem-p.r.ry ostomies,and incisional hernias frequently develop after colostomy or ileostomy *** use of synthetic meshes to reinforce the abdominal wall has reduced hernia *** meshes have also been used to enhance healing,p.r.icularly in contaminated *** tissue matrices(r-TMs),which include a biologic scaffold of native extracellular matrix and a syn-thetic component for added strength/durability,are designed to take advantage of aspects of both synthetic and biologic *** date,rTMs have not been rep.r.ed to reinforce the abdominal wall following stoma *** Twenty-eight patients were selected with a p.r.stomal and/or incisional hernia who had received a temp.r.ry ileostomy or colostomy for fecal diversion after rectal cancer treatment or *** hernia repair and proximal stoma closure,rTM(OviTex®1S p.r.anent or OviTex®Lpr)was placed to reinforce the abdominal wall using a lap.r.scopic,robotic,or open surgical ***-op.r.tive follow-up was p.r.ormed at 1 month and 1 *** recurrence was determined by physical examination and,when necessary,via computed tomo-graphy *** endpoints included length of hospital stay,time to return to work,and hospital *** complications of the wound/repair site included presence of surgical site infection,seroma,hematoma,wound dehiscence,or fistula *** The observational study cohort included 16 male and 12 female patients with average age of 58.5 years±16.3 years and average body mass index of 26.2 kg/m^(2)±4.1 kg/m^(2).patients presented with a p.r.stomal hernia(75.0%),in-cisional hernia(14.3%),or combined p.r.stomal/incisional hernia(10.7%).Using a lap.r.scopic(53.6%),robotic(35.7%),or open(10.7%)technique,rTMs(OviTex®Lpr:82.1%,OviTex®1S:17.9%)were placed using sublay(82.1%)or intrap.r.toneal onlay(IpOM;17.9%)mesh *** 1-mo

关键词： reinforced tissue matrix reinforced forestomach matrix Ileostomy Colostomy Ostomy takedown Incisional hernia Abdominal wall