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modelling the Effect of self-Immunity and the Impacts of Asymptomatic and symptomatic Individuals on COVID-19 Outbreak

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Computer modeling in Engineering & sciences 2020年第12期125卷 1033-1060页

作者： m.H.A.Biswas m.A.islam s.Akter s.mandal m.s.Khatun s.A.samad A.K.Paul m.R.Khatun mathematics Discipline Science Engineering and Technology SchoolKhulna UniversityKhulna9208Bangladesh Department of mathematics Bangabandhu Sheikh Mujibur Rahman Science and Technology UniversityGopalganj8100Bangladesh

COVID-19 is one of themost highly infectious diseases ever emerged and caused by newly discovered severe acute respiratory syndrome coronavirus 2(sARs-CoV-2).It has already led the entire world to health and economic *** has invaded the whole universe all most every *** present study demonstrates with a nine mutually exclusive compartmental model on transmission dynamics of this pandemic disease(COVID-19),with special focus on the transmissibility of symptomatic and asymptomatic infection from susceptible ***,the compartmental model has been investigated with mathematical analysis and computer simulations in order to understand the dynamics of COVID-19 ***,mathematical analysis of the model has been carried out in broadly by illustrating some well-known methods including exactness,equilibrium and stability analysis in terms of basic reproduction *** investigate the sensitivity of the model with respect to the variation of the parameters’***,computer simulations are performed to illustrate the *** analysis reveals that the death rate from coronavirus disease increases as the infection rate increases,whereas infection rate extensively decreases with the increase of quarantined *** quarantined individuals also lead to increase the concentration of recovered ***,the infection rate of COVID-19 increases more surprisingly as the rate of asymptomatic individuals increases than that of the symptomatic ***,the infection rate decreases significantly due to increase of self-immunity rate.

关键词： COVID-19 asymptomatic and symptomatic individuals selfimmunity mathematical model basic reproductive ratio numerical simulations

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Preventive effect of ethanol extract of Alpinia calcarata Rosc on Ehrlich's ascitic carcinoma cell induced malignant ascites in mice

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Asian Pacific Journal of Tropical medicine 2012年第2期5卷 121-125页

作者： Rasida Perveen Farhadul islam Jahanara Khanum Tanzima Yeasmin Department of Biochemistry and molecular Biology University of RajshahiRajshahi -6205 Bangladesh

Objective:To explore cytotoxic activity of ethanol extract of Alpinia calcarata Rose(EEAC) rhizome against Ehiiich ascites carcinoma(EAC) tumor bearing swiss Albino ***: In the present study,its anti-neoplastic activity has been studied by monitoring parameters like tumor weight measurement,survival time,tumor cell growth inhibition,haematological characteristics ***:It was found that EEAC at dose 8 mg/kg/day(i.p.) significantly decreased tumor weight(62.0%;Psed life span(70.25%;P mor cell growth rate(85.7%;Pmparison to those of EAC bearing *** plant extract also improved the depleted haematological parameters like RBC WBC,Hb%,differential counts(***,neutrophils,monocytes etc) of EAC bearing mice towards *** host toxic effects were not very high and recovered gradually towards normal within a few days after ***:EEAC exhibits potent in vivo cytotoxic activity against EAC tumor bearing swiss Albino ***,the plant can be considered as a probable new source of antitumor agents.

关键词： Antineoplstic Antitumor agents EAC cell Alpinia calcarata Rose Haematology

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Factors Influencing International Trade:A Gravity model Analysis of Bangladesh’s Trade

Factors Influencing International Trade:A Gravity Model Anal...

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作者： mD sHARIFUL islam 山东大学

学位级别：硕士

双边贸易是两国之间促进贸易和投资的货物交换。为了促进贸易和投资,两国将减少或取消税收、进口限制、出口限制和其他贸易壁垒。本研究旨在确定影响孟加拉国双边贸易模式的因素,以及区域贸易协定（RTAs）和优惠贸易协定（PTAs）如何改... 详细信息

双边贸易是两国之间促进贸易和投资的货物交换。为了促进贸易和投资,两国将减少或取消税收、进口限制、出口限制和其他贸易壁垒。本研究旨在确定影响孟加拉国双边贸易模式的因素,以及区域贸易协定（RTAs）和优惠贸易协定（PTAs）如何改变该国的贸易模式。为了估算面板引力模型（panel gravity model）中孟加拉国在2000年至2019年20年间对其51个贸易伙伴的贸易流量,编制了一组具体数据集。研究结果表明,孟加拉国的国内生产总值（GDP）规模、汇率和贸易开放已被证明是孟加拉国对外贸易的关键影响因素。区域贸易协定正在以最小的规模影响孟加拉国的贸易。地理隔离对贸易有重大影响。人们注意到,虽然孟加拉国没有加入欧洲联盟和北美自由贸易协定（NAFATA）,但由于普遍优惠制设施和成衣工业的竞争优势,孟加拉国正在向这些目的地进一步出口。由于以下几个原因,本研究是—个新颖而重要的贡献:考虑到市场动态和孟加拉国贸易趋势最近的转变,以往用引力模型分析孟加拉国贸易模式的研究已经过时。所以,这是重温这个话题的最佳时机。第二,最重要的是,之前的研究从未使用PPmL估计,有限元或REm不足以得出的结果如果零贸易存在的数据集。这项研究有助于填补研究空白,回顾历史上最活跃的部分或最近的贸易和包容的PPmL估计产生无偏和—致的估计量。

关键词：引力模型面板数据 PPmL FEm REm 国际贸易中的孟加拉国

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Collapsing scenario for the k-essence emergent generalized Vaidya spacetime in the context of massive gravity's rainbow

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Chinese Physics C 2022年第12期46卷 271-287页

作者： saibal Ray Arijit Panda Bivash majumder md.Rabiul islam Goutam manna Centre for Cosmology Astrophysics and Space Science(CCASS)GLA UniversityMathura 281406Uttar PradeshIndia Department of Physics Prabhat Kumar CollegeContaiPurba Medinipur 721404India&Department of PhysicsRaiganj UniversityRaiganjUttar Dinajpur 733134West BengalIndia Department of mathematics Prabhat Kumar CollegeContaiPurba Medinipur-721404India Department of Physics Raiganj UniversityRaiganjUttar Dinajpur 733134West BengalIndia Department of Physics Prabhat Kumar CollegeContaiPurba Medinipur-721404India

In this study,we investigate the collapsing scenario for the k-essence emergent Vaidya spacetime in the context of massive gravity's *** this study,we consider that the background metric is Vaidya spacetime in massive gravity's *** show that the k-essence emergent gravity metric closely resembles the new type of generalized Vaidya massive gravity metric with the rainbow deformations for null fluid collapse,where we consider the k-essence scalar field as a function solely of the advanced or the retarded *** k-essence emergent Vaidya massive gravity rainbow mass function is also *** new type k-essence emergent Vaidya massive gravity rainbow metric satisfies the required energy *** existence of a locally naked central singularity and the strength and strongness of the singularities for the rainbow deformations of the k-essence emergent Vaidya massive gravity metric are the interesting outcomes of the present work.

关键词： classical general relativity physics of black holes classical black holes k-essence

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A systematic study on mycochemical profiles, antioxidant, and anti-inflammatory activities of 30 varieties of Jew’s ear(Auricularia auricula-judae)

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Food science and Human Wellness 2022年第4期11卷 781-794页

作者： Tahidul islam Fangjie Yao Wenyi Kang Lixin Lu Baojun Xu College of Horticulture Jilin Agricultural UniversityChangchun 130118China Food science and Technology Program BNU-HKBU United International CollegeZhuhai 519087China National R&D Center for Edible Fungus Processing Technology Henan UniversityKaifeng 475004China

The health-promoting properties and chemical profiles of 30 Jew’s ear mushroom varieties were investigated. The antioxidant properties were determined by ferric reducing antioxidant power(FRAP), 1,1-diphenyl-2-picrylhydrazyl(DPPH) free radical scavenging, 2,2’-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)(ABTs) free radical scavenging, and metal chelating ability(mCA) assays, while phenolic profiles were determined by total phenol content(TPC) and total flavonoid content(TFC) colorimetric assays. Total carbohydrate, β-glucan, and melanin contents were determined by colorimetric methods. 5’-Nucleotides, vitamin D_(2), ergosterol, and ergothioneine contents were determined by high performance liquid chromatography(HPLC). Anti-inflammation activities of Jew’s ear were evaluated by the colorimetric protease inhibitory method. The results showed that Jew’s ear mushrooms possessed substantial phenolics and antioxidant properties. All the Jew’s ear varieties contain high amount of total carbohydrate, β-glucan, reducing sugar, melanin, pectin, vitamin D2, ergosterol, and ergothioneine. The current findings could provide scientific information for breeders to nurture desired varieties and for food industry to develop new health promoting products.

关键词： Auricularia auricula-judae Phenolic compounds Antioxidant properties Chemical composition Anti-inflammation High performance liquid chromatography

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PREssURE FLOW OF A sECOND GRADE FLUID THROUGH A CHANNEL OF VARYING WIDTH WITH APPLICATION TO sTENOsED ARTERY

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International Journal of Biomathematics 2013年第3期6卷 81-100页

作者： A. m. sIDDIQUI T. HAROON Z. BANO s. islam Pennsylvania state University York Campus Edgecomb PA 1703 USA Department of mathematics COmsATs Institute of Information TechnologyPark Road Chak Shehzad Islarnabad ~000 Pakistan Department of mathematics COmsATs Institute of Information TechnologyPark Road Chak Shehzad Islamabad 44000 Pakistan Department mathematicsAbdul Wali Khan University mardan Pakistan

Analytical solutions are obtained for steady flow of an incompressible second grade fluid in an axisymmetric channel of varying width. Three approximate methods are used depending upon three different geometrical configuration. The results obtained are applied to study the flow of a second grade fluid through a smooth constriction. To understand the flow behavior near stenosis, resistance to the flow, shear stress at the wall and stress at the stenosis throat are calculated. The results obtained are numerically evaluated for different values of dimensionless non-Newtonian parameters λ1 and λ2 and maximum height of the stenosis δm. It is observed that as we increase the value of these parameters the resistance to the flow, wall shear stress and stress at the stenosis throat increase.

关键词： second grade fluid varying width, stenosis resistance to flow.

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Low-temperature oxidation behavior of mosi_2 powders

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Journal of University of science and Technology Beijing 2007年第6期14卷 558-561页

作者： Peizhong Feng Xuanhui Qu islam s. Humail Xueli Du state Key Laboratory for Advanced metals and materials University of Science and Technology Beijing Beijing 100083 China school of materials science and Engineering China University of Mining and Technology Xuzhou 221116 China

The oxidation behavior of molybdenum disilicide （mosi2） powders at 400, 500, and 600℃ for 12 h in air were investigated by using X-ray diffraction （XRD） and transmission electron microscopic （TEm） techniques. significant changes were observed in volume, mass, and color. Especially at 500℃, the volume expansion was found to be as high as 7-8 times, the color changed from black to yellow-white, and the mass gain was about 169.34% after 8 h, with siO2 and moO3 as main reaction products. The gains in volume and mass were less at 400 and 600℃ compared with those at 500℃, probably due to the less reaction rate at 400℃ and the formation of silica glass scale at 600℃, which would protect the matrix and restrain the diffusion of oxygen and molybdenum. Thus, the accelerated oxidation behavior of mosi2 powder appeared at 500℃ and the volume expansion was the sign of accelerated oxidation.

关键词： molybdenum disilicide low-temperature oxidation accelerated oxidation volume expansion

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Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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A systematic review of progenitor survival and maturation in Parkinsonian models

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Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&Therapeutics and Galway Neuroscience Center University of GalwayGalwayIreland

stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the Pubmed database was completed to identify relevant studies published up to march *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged froms transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant

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Perceived stigma and quality of life in Parkinson’s disease with additional health conditions

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General Psychiatry 2022年第3期35卷 192-200页

作者： samia s islam sandy Neargarder shraddha B Kinger Joshua T Fox-Fuller Robert D salazar Alice Cronin-Golomb Department of Psychological and Brain sciences Boston UniversityBostonMassachusettsUSA Department of Psychology Bridgewater State UniversityBridgewaterMassachusettsUSA

Background Parkinson’s disease(PD)is associated with perceived stigma and affects quality of life(QoL).Additional health conditions may influence these consequences of *** This study assessed the impact of health conditions on perceived stigma and QoL in persons with *** hypothesised that individuals with more health conditions would report more stigma and poorer *** also examined the contributions of demographic and clinical characteristics to the correlations between health conditions and perceived stigma/*** We identified 196 eligible participants from the Boston University Online survey study of Parkinson’s Disease and examined their health history,performance on multiple stigma measures,and scores on the 39-item Parkinson’s Disease Questionnaire assessing *** At least one health condition was reported by 79%of the sample,with a median of 2 and a range of 0–7 health *** perceived stigma and poorer QoL were associated with thyroid disease,depression,anxiety,and the total number of health *** correlations were related to younger age,less education,and earlier disease *** health conditions(high blood pressure,back/leg surgery,headache,cancer/tumours,and heart disease)were not significantly correlated with stigma or *** Having more health conditions,or thyroid disease,depression,or anxiety,was associated with more perceived stigma and poorer QoL,with younger age,less education,and earlier disease onset affecting the *** is important to consider the burden of health conditions and how they affect persons with PD with specific clinical characteristics.

关键词： younger life education

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