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Biomedical and Environmental Sciences 2010年第4期23卷 305-311页

作者： sohail ejaz AHMED ejaz AMARA sohail CHAE WOONG LIM Department of Clinical Neurosciences Neurology Unit Addenbrookes Hospital University of Cambridge District Headquarter Hospital Government Social Security Hospital Gujranwala Pakistan Biosafety Research Institute and College of Veterinary Medicine Chonbuk National University

Objective Embryonic movements （EM） and angiogenesis pathways are evolutionarily conserved mechanisms which are essential for proper embryonic development. Deviations in these processes by exposure to cigarette smoke condensate （CSC） may cause vascular and morphogenetic disorders. Methods Using chicken and mouse embryos, we have demonstrated the in vivo effects of CSC on EM, vascular development, and organogenesis. Results Examination of the CSC exposed chicken embryos revealed a significant reduction in EM, stunted growth, deviated pattern of blood vessels, hemorrhages, and localized necrosis. Likewise, mouse embryos that were exposed to CSC at E8.5 and E9.5 died between E11.5 and E12.5, respectively. These mouse embryos showed defects in morphogenesis and remodeling of the embryonic vasculature, while littermate controls showed normal development. Conclusion Cigarette smoking during pregnancy is fatal for growing embryos. CSC may induce the remodeling of embryonic vasculature, leading to various pathologies.

关键词： Angiogenesis Embryonic movements Cigarette smoke condensate Vascular remodeling

Mutagenic and cytotoxic potential of Endosulfan and Lambda-cyhalothrin—In vitro study describing individual and combined effects of pesticides

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Journal of Environmental Sciences 2014年第7期26卷 1471-1479页

作者： Umber Saleem sohail ejaz Muhammad Ashraf Muhammad Ovais Omer Imran Iltaf Zainab Batool Riffat Fatima Msbah Afzal Department of Pharmacology & Toxicology University of Veterinary and Animal Sciences Lahore 54000 Pakistan Department of Clinical Neurosciences Neurology Unit Addenbrooke's Hospital University of Cambridge Cambridge UK Microbiology Section Quality Operations Laboratory University of Veterinary and Animal Sciences Lahore Pakistan

Excessive use of pesticides poses increased risks to non target species including humans. In the developing countries, lack of proper awareness about the toxic potential of pesticides makes the farmer more vulnerable to pesticide linked toxicities, which could lead to diverse pathological conditions. The toxic potential of a pesticide could be determined by their ability to induce genetic mutations and cytotoxicity. Hence, determination of genetic mutation and cytotoxicity of each pesticide is unavoidable to legislate health and safety appraisal about pesticides. The objective of current investigation was to determine the genotoxic and cytotoxic potential of Endosulfan（EN） and Lambda-cyhalothrin（LC）; individually and in combination. 3-（4,5-Dimethylthiazol-2-yl）-2,5-Diphenyltetrazolium Bromide（MTT） assay was utilized to determine cytotoxicity, while two mutant histidine dependent Salmonella strains（TA98, TA100） were used to determine the mutagenicity of EN and ***, mutagenicity assay was conducted with and without S9 to evaluate the effects of metabolic activation on mutagenicity. Even though a dose dependent increase in the number of revertant colonies was detected with EN against both bacterial strains, a highly significant（p 〈 0.05） increase in the mutagenicity was detected in TA98 with S9. In comparison, data obtained from LC revealed less mutagenic potential than EN. Surprisingly,the non-mutagenic individual-concentrations of EN and LC showed dose dependent mutagenicity when combined. Combination of EN and LC synergistically induced mutagenicity both in TA98 and TA100. MTT assay spotlighted comparable dose dependent cytotoxicity effects of both pesticides. Interestingly, the combination of EN and LC produced increased reversion and cytotoxicity at lower doses as compared to each pesticide, concluding that pesticide exposure even at sub-lethal doses can produce cytotoxicity and genetic mutations, which could lead to carcinogenicity.

关键词： Endosulfan Lambda-cyhalothrin Mutagenicity Cytotoxicity

Total Particulate Matter and Wound Healing: An in vivo Study with Histological Insights

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Biomedical and Environmental Sciences 2009年第4期22卷 278-287页

作者： sohail ejaz MUHAMMAD ASHRAF MUHAMMAD NAWAZ CHAE WOONG LIM Department of Clinical Neurosciences Neurology Unit Addenbrookes Hospital University of Cambridge Angiogenesis and Toxicology Research Laboratory Department of Toxicology and Pharmacology University of Veterinary and Animal Sciences Biosafety Research Institute and College of Veterinary Medicine Chonbuk National University

Objectives Wound healing in the skin is a multifarious orchestration of cellular processes and cigarette smoking may be a cause for delayed wound healing. The aim of this study was to investigate the plausible association between exposures of cigarette total particulate matter （TPM） and wound healing. Methods An in vivo wound healing model of mice was established for determination of assorted events of wound healing, dermal matrix regeneration, re-epithelialization, and neovascularization. A total of 72 adult mice, separated in eight groups, were exposed to TPM for 12 days. Results A highly considerable diminution in wound closure （P〈0.001） was pragmatic among all TPM-treated mice from day 6 to day 8 post-wounding. Histological investigations unveiled a noteworthy impede in the outcome of re-epithelialization, dermal matrix regeneration and maturation of collagen bundles among all TPM-exposed wounds. Delayed commencement of neovascularization was pragmatic among all TPM-treated mice, on day 12 post wounding. Abbot curve, angular spectrum, and other different parameters of 3D surface behavior of wounds revealed a very highly significant reduction （P〈0.001） in angiogenesis on days 6 and 8 post-wounding, which points that application of TPM instigates extensive delay in trigging the progression of angiogenesis, resulting in delayed onset of wound healing. Conclusion Our annotations validate the damaging effects of TPM on wound healing and excessive use of TPM may lead to the production of chronic wounds and oral ulcers.

关键词： Cigarette Total particulate matter Wound healing Re-epithelialization Angiogenesis

Analysis of cerium substitution in Co-Sr based spinel ferrites for high frequency application

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Journal of Rare Earths 2024年第9期42卷 1755-1763页

作者： Laura Khudaysh Inas A.Ahmed Syeda Rabia ejaz Sajjad Ahmad Khan Yasir A.Haleem Mohamed M.Ibrahim Mahmood Ali Hafiz Muhammad Tahir Farid Zeinhom M.El-Bahy Department of Physics Faculty of ScienceJazan University Department of Chemistry Faculty of ScienceKing Khalid University Department of Physics The Government Sadiq College Women University Institute of Physics Khwaja Fareed University of Engineering and Information Technology Department of Chemistry College of ScienceTaif University Centre of Excellence in Solid State Physics University of the Punjab Department of Physics Government College Department of Chemistry Faculty of ScienceAl-Azhar University

Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic *** sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co0.6Sr0.4CexFe2-xO4. Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized *** the utilization of the M-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and *** ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation *** logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is *** a change in the amount of cerium,the activation energy goes up from 0.19 to *** changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were *** the frequency goes up,the dielectric constant goes *** ferrites that have been made better in every way can be used in high-frequency applications.

关键词： Activation energy DC electrical resistance Remanence magnetization Cobalt strontium spinel ferrites High frequency application Rare earths

Computational Modeling of Reaction-Diffusion COVID-19 Model Having Isolated Compartment

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1719-1743页

作者： Muhammad Shoaib Arif Kamaleldin Abodayeh Asad ejaz Department of Mathematics and Sciences College of Humanities and SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Mathematics Air UniversityPAF Complex E-9Islamabad44000Pakistan

Cases of COVID-19 and its variant omicron are raised all across the *** most lethal form and effect of COVID-19 are the omicron version,which has been reported in tens of thousands of cases daily in numerous *** WHO(World health organization)records on 30 December 2021,the cases of COVID-19 were found to be maximum for which boarding individuals were found 1,524,266,active,recovered,and discharge were found to be 82,402 and 34,258,778,*** there were 160,989 active cases,33,614,434 cured cases,456,386 total deaths,and 605,885,769 total samples *** far,1,438,322,742 individuals have been *** coronavirus or COVID-19 is inciting panic for several *** is a new virus that has affected the whole *** have introduced certain ways to prevent the *** can lower the danger of infection by reducing the contact rate with other *** crowded places and social events withmany people reduces the chance of one being exposed to the *** deadly COVID-19 spreads *** is thought that the upcoming waves of this pandemicwill be evenmore *** have presented severalmathematical models to study the pandemic and predict future *** need of the hour is to restrict the mobility to control the infection from ***,separating affected individuals from healthy people is essential to control the *** consider the COVID-19 model in which the population is divided into five *** present model presents the population’s diffusion effects on all susceptible,exposed,infected,isolated,and recovered *** reproductive number,which has a key role in the infectious models,is *** equilibrium points and their stability is *** numerical simulations,finite difference(FD)schemes like nonstandard finite difference(NSFD),forward in time central in space(FTCS),and Crank Nicolson(CN)schemes are *** core characteristics

关键词： Reproductive number stability Routh Hurwitz criterion variational matrix NSFD scheme FTCS scheme Crank Nicolson scheme consistency

Temperature-controlled fabrication of hydrophilic manganese oxide microspheres as high-performance electrode materials for supercapacitors

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Chinese Chemical Letters 2023年第5期34卷 516-520页

作者： Yuchen Wang Yaoyu Liu Ahsan ejaz Kai Yan Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology School of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Department of Civil Engineering Mirpur University of Science and TechnologyAJKMirpur 10250Pakistan

The supercapacitive properties of manganese oxides(MnO_(x))are strongly affected by their crystal ***,the relationship between the crystal structure and supercapacitive performance of Mn O_(x)is ***,a temperature-controlled fabrication method was developed to achieve MnO_(2),Mn_(3)O_(4),MnO and Mn_(2)O_(3)microspheres with various crystal structure as electrode materials tunable for *** detailed material and electrochemical characterizations revealed the structureactivity relationship of Mn O_(x)microspheres by systematically investigating the effect of valence state,specific surface area,conductivity and morphology on supercapacitive *** these MnO_(x)materials,nanoneedle-like Mn O_(2)delivered a relatively high specific capacitance of 274.1 F/g at 1 A/g due to a high Mn valence state of+4,a large specific surface area of 113.4 m^(2)/g and a desirable electronic conductivity of 1.73×10^(-5)S/***,MnO_(2)presented a remarkable cycle stability with 115%capacitance retention after 10,000 cycles owing to the enhancement of *** work not only provides a facile strategy to modulate MnO_(x)crystal structure,but also offers a deep understanding of structure-dependent supercapacitive performance of MnO_(x).

关键词： Temperature-controlled Manganese oxide Microsphere Supercapacitors Hydrophilic

Numerical Study for Magnetohydrodynamic(MHD)Unsteady Maxwell Nanofluid Flow Impinging on Heated Stretching Sheet

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Computer Modeling in Engineering & Sciences 2022年第11期133卷 303-325页

作者： Muhammad Shoaib Arif Muhammad Jhangir Yasir Nawaz Imran Abbas Kamaleldin Abodayeh Asad ejaz Department of Mathematics and Sciences College of Humanities and SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Mathematics Air UniversityIslamabad44000Pakistan

The numerous applications of Maxwell Nanofluid Stagnation Point Flow,such as those in production industries,the processing of polymers,compression,power generation,lubrication systems,food manufacturing and air conditioning,among other applications,require further research into the effects of various parameters on flow *** this paper,a study has been carried out for the heat andmass transfer of Maxwell nanofluid flow over the heated stretching sheet.A mathematical model with constitutive expressions is constructed in partial differential equations(PDEs)through obligatory basic conservation laws.A series of transformations are then used to take the system into an ordinary differential equation(ODE).The boundary conditions(BCs)are also treated similarly for transforming into first-order ordinary differential equations(ODEs).Then these ODEs are computed by using the Shooting *** effect of factors on the skin friction coefficient,the local Nusselt number,and the local Sherwood number are explored,and the results are displayed *** obtained results demonstrate that by increasing the values of the Maxwell and slip velocity parameters,velocity *** investigators tasked with addressing unresolved difficulties in the realm of enclosures used in industry and engineering,we thought this work would serve as a guide.

关键词： Maxwell fluid stagnation point flow heat and mass transfer thermal radiations shooting method

Stability Analysis of Predator-Prey System with Consuming Resource and Disease in Predator Species

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Computer Modeling in Engineering & Sciences 2022年第8期132卷 489-506页

作者： Asad ejaz Yasir Nawaz Muhammad Shoaib Arif Daoud S.Mashat Kamaleldin Abodayeh Department of Mathematics Air UniversityPAF Complex E-9Islamabad44000Pakistan Department of Mathematics King Abdulaziz UniversityJeddah22254Saudi Arabia Department of Mathematics and Sciences College of Humanities and SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia

The present study is concerned with formulating a predator-prey eco-epidemiological mathematical model assuming that an infection exists in the predator *** two classes of predator species(susceptible and infected)compete for the same sources available in the environment with the predation *** is assumed that the disease does not spread *** proposed model is analyzed for the stability of the coexistence of the predators and *** fixed points are carried out,and the coexisting fixed point is studied in detail by constructing the Lyapunov *** movement of species in search of food or protection in their habitat has a significant influence,examined through *** ecological influences of self-diffusion on the population density of both species are *** is theoretically proved that all the under consideration species can coexist in the same *** coexistence fixed point is discussed for both diffusive and non-diffusive ***,a numerical scheme is constructed for solving time-dependent partial differential *** stability of the scheme is given,and it is applied for solving presently modified eco-epidemiological mathematical model with and without *** comparison of the constructed scheme with two exiting schemes,Backward in Time and Central in Space(BTCS)and Crank Nicolson,is also given in the form of ***,we run a computer simulation to determine the effectiveness of the proposed numerical *** readers’convenience,a computational code for the proposed discrete model scheme may be made available upon request.

关键词： Eco-epidemiology self-diffusion stability Lyapunov function proposed numerical scheme

Development of stability-preserving time-limited model reduction framework for 2-D and 1-D models with error bound

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Control Theory and Technology 2022年第3期20卷 371-381页

作者： Muhammad Imran Syeda Hira Ambreen Syed Nooh Hamdani Muhammad Imran Muhammad ejaz Naveed Maria Siddiqui Department of Electrical Engineering Military College of Signals(MCS)National University of Sciences and Technology(NUST)Islamabad43000Pakistan Department of Electrical Engineering Sir Syed(Center For Advanced Studies)Institute of Technology(SSCASE)Islamabad43000Pakistan College of Science and Humanities Rumah Majmaah UniversityRumahKingdom of Saudi Arabia

Due to their complex structure,2-D models are challenging to work with;additionally,simulation,analysis,design,and control get increasingly difficult as the order of the model ***,in particular time intervals,Gawronski and Juang’s time-limited model reduction schemes produce an unstable reduced-order model for the 2-D and 1-D *** revealed some stability preservation solutions to address this key flaw which ensure the stability of 1-D reduced-order systems;nevertheless,these strategies result in large approximation ***,to the best of the authors’knowledge,there is no literature available for the stability preserving time-limited-interval Gramian-based model reduction framework for the 2-D discrete-time *** this article,2-D models are decomposed into two separate sub-models(i.e.,two cascaded 1-D models)using the condition of minimal *** reduction procedures are conducted on these obtained two 1-D sub-models using limited-time *** suggested methodology works for both 2-D and 1-D ***,the suggested methodology gives the stability of the reduced model as well as a priori error-bound expressions for the 2-D and 1-D *** results and comparisons between existing and suggested methodologies are provided to demonstrate the effectiveness of the suggested methodology.

关键词： Model reduction Weighted Gramian Limited interval Gramian Minimal realization Approximation error Error bound

Optimal Parameter Estimation of Transmission Line Using Chaotic Initialized Time-Varying PSO Algorithm

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Computers, Materials & Continua 2022年第4期71卷 269-285页

作者： Abdullah Shoukat Muhammad Ali Mughal Saifullah Younus Gondal Farhana Umer Tahir ejaz Ashiq Hussain Department of Electrical Engineering HITEC UniversityTaxila47080Pakistan Department of Electrical Engineering Islamia UniversityBahawalpur63100Pakistan Department of Electrical Engineering Iqra UniversityIslamabad44000Pakistan

Transmission line is a vital part of the power system that connects two major points,the generation,and the *** an efficient design,stable control,and steady operation of the power system,adequate knowledge of the transmission line parameters resistance,inductance,capacitance,and conductance is of great *** parameters are essential for transmission network expansion planning in which a new parallel line is needed to be installed due to increased load demand or the overhead line is replaced with an underground *** paper presents a method to optimally estimate the parameters using the input-output quantities i.e.,voltages,currents,and power factor of the transmission *** equivalentπ-network model is used and the terminal data i.e.,sending-end and receiving-end quantities are assumed as available measured *** parameter estimation problem is converted to an optimization problem by formulating an error-minimizing objective *** improved particle swarm optimization(PSO)in terms of time-varying control parameters and chaos-based initialization is used to optimally estimate the line *** cases are considered for parameter estimation,the first case is when the line conductance is neglected and in the second case,the conductance is considered into *** results obtained by the improved algorithm are compared with the standard version of the algorithm,firefly algorithm and artificial bee colony algorithm for 30 number of *** is concluded that the improved algorithm is tremendously sufficient in estimating the line parameters in both cases validated by low error values and statistical analysis,comparatively.

关键词： Chaos parameter estimation transmission line time-varying particle swarm optimization pi-network