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mathematical model for the ciliary-induced transport of seminal liquids through the ductuli efferentes

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International Journal of Biomathematics 2017年第3期10卷 1-17页

作者： A. A. Farooq A. m. siddiqui Department of mathematics COmSATS Institute of Information Technology Tobe Camp Abbottabad Pakistan Department of mathematics Pennsylvania State University York Campus York PA 17403-3398 USA

This study describes the consequences of the ciliary motion on the transport of seminal liquid through the ductus efferentes of the male reproductive tract. By assuming the seminal liquid as a couple stress fluid, we have formulated a mathematical model for a two-dimensional flow through an axially symmetric tube whose inner surface is ciliated in the form of a metachronal wave. The governing system consists of nonlinear coupled partial differential equations which is reduced to a system of ordinary differential equa- tions by utilizing the long wavelength approximation in an environment of the inertia free flow. Exact solutions for the velocity distribution, the pressure gradient and the stream function are obtained in terms of the couple stress parameters and the ciliary metachronism. Special attention is given to the pumping and the trapping characteristics due to the cilia motility. The study reveals that the ciliary pumping has to be more efficient to transport a couple stress fluid as compared to a Newtonian fluid. moreover, the theoretical results for the couple stress fluid are found to be in good agreement with those reported by IT. J. Laxdner and W. J. Shack, Cilia transport, Bull. math, Biophys, 34 （1972） 325-335]. The analytical results are also displayed in graphical form.

关键词： Ciliary-induced flow metachronal wave couple stress fluid axisymmetric tube.

On study of horizontal thin film flow of Sisko fluid due to surface tension gradient

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Applied mathematics and mechanics(English Edition) 2015年第7期36卷 847-862页

作者： A.m.siddiqui H.ASHRAF A.WALAIT T.HAROON Department of mathematics York CampusPennsylvania State University Department of mathematics COMSATS Institute of Information Technology

The present paper is concerned with the steady thin film flow of the Sisko fluid on a horizontal moving plate, where the surface tension gradient is a driving mechanism. The analytic solution for the resulting nonlinear ordinary differential equation is obtained by the Adomian decomposition method （ADm）. The physical quantities are derived including the pressure profile, the velocity profile, the maximum residue time, the stationary points, the volume flow rate, the average film velocity, the uniform film thickness, the shear stress, the surface tension profile~ and the vorticity vector. It is found that the velocity of the Sisko fluid film decreases when the fluid behavior index and the Sisko fluid parameter increase, whereas it increases with an increase in the inverse capillary number. An increase in the inverse capillary number results in an increase in the surface tension which in turn results in an increase in the surface tension gradient on the Sisko fluid film. The locations of the stationary points are shifted towards the moving plate with the increase in the inverse capillary number, and vice versa locations for the stationary points are found with the increasing Sisko fluid parameter. Furthermore, shear thinning and shear thickening characteristics of the Sisko fluid are discussed. A comparison is made between the Sisko fluid film and the Newtonian fluid film.

关键词： thin film flow Sisko fluid model horizontal moving plate surface tension gradient analytic solution Adomian decomposition method (ADm)

Foliation and the First Law of Black Hole Thermodynamics

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Chinese Physics Letters 2011年第5期28卷 54-56页

作者： Azad A.siddiqui Syed muhammad Jawwad Riaz m.Akbar Department of Basic Sciences and Humanities EME CollegeNational University of Sciences and Technology(NUST)Peshawar RoadRawalpindiPakistan Centre for Advanced mathematics and Physics National University of Sciences and Technology(NUST)Sector H-12IslamabadPakistan

There has been lots of interest in exploring the thermodynamic properties at the horizon of a black hole *** has been shown earlier that for different spacetimes,the Einstein field equations at the horizon can be expressed as the first law of black hole *** the idea of foliation,we develop a simpler procedure toobtain such *** considerγ=constant slices,for the Schwarzschild and Reissner-Nordstrom black hole *** Einstein field equations for the induced 3-dimensional metrics of the hypersurfaces are expressed in thermodynamic quantities under the virtual displacements of the *** expected,it is found that the field equations of the induced metric corresponding to the horizon can be written as afirst law of black hole *** is to be mentioned here that our procedure is much easier,to obtain such results,as here one has to essentially deal with(n-1)-dimensional induced metric for an n-dimensional spacetime.

关键词： thermodynamic Einstein mentioned

Effect of Cu/Zn Substitution in mgO Nanostructures for Tuning the Optical Bandgap and Structural Properties

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Journal of Wuhan University of Technology(materials Science) 2022年第6期37卷 1035-1040页

作者： ATIF Dawar S NASEEm Shah m ASIF siddiqui YASmEEN Bibi Department of Physics Federal Urdu University of ArtsScience and TechnologyKarachiPakistan Department of Chemistry Federal Urdu University of ArtsScience and TechnologyKarachiPakistan

Low cost co-precipitation method was used to synthesize Cu(0-0.05)doped mgO samples with fixed concertation of Zn=0.01.X-ray diffraction(XRD)spectra confirmed the phase purity of the samples for 0≤Cu≤0.03 doping *** secondary phase for 0.04≤Cu≤0.05 exhibited the formation of mixed metal *** crystallite size was found to increase from 17.5 to 23.5 nm for 0≤Cu≤0.03 and then decreased from 22 to 18.5 nm for 0.04≤Cu≤*** estimated bandgap first reduced from 5.48 to 4.88 eV and then increased from 5.21 to 5.36 *** morphology of the samples transformed from spheroidal shape to star-like *** obtained results reveal that the structural and optical property are in good agreement with the morphological *** peak shifting towards the lower values of vibrational frequency from 694 to 579 cm^(-1) confirms the incorporation of Cu/Zn in mg-O *** tuning of optical bandgap and structural properties with varying dopant concentration in mgO nanomaterials can be used for multifunctional modern energy storage and optoelectronic devices.

关键词： Cu/Zn doping mgO optical bandgap morphology vibrational modes

EXACT SOLUTIONS FOR mAGNETOHYDRODYNAmIC FLOW IN A ROTATING FLUID

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Acta mechanica Sinica 2002年第3期18卷 244-251页

作者： S. Asghar masood Khan A.m. siddiqui T. Hayat Department of mathematics Quaid-i-Azam University Islamabad Pakistan Department of mathematics Pennsylvania State University York Campus 1031 Edgecomb Avenue New York PA 17403 USA

An analytical solution is obtained for the flow due to solid-body rotations an oscillating porous disk and of a fluid at infinity. Neglecting the induced magnetic field, the effects of the transversely applied magnetic field on the flow are studied. Further, the flow confined between two disks is also discussed. It is found that an infinite number of solutions exist for the flow confined between two disks.

关键词： rotating fluid porous disk double disks magnetohydrodynamic flow

Incidence and predictors of hypocalcemia in end-stage renal disease patients on denosumab therapy: A systematic review and metaanalysis

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World Journal of meta-Analysis 2024年第3期12卷 68-78页

作者： Abdul Hannan siddiqui misbah Shaikh Afia Salman muhammad Ahmed Ali Fahim Fizzah Batool Tahreem mari Sarah musani muneeb Fareed Rooma Rehan Amna Hassni Urooj Nizami Ayesha Amir Abdul moeed Salim R Surani Department of Internal medicine Dow University of Health SciencesKarachi 74200SindhPakistan Department of medicine&Pharmacology Texas A&M UniversityCollege StationTX 77843United States

BACKGROUND Denosumab inhibits the receptor activator of nuclear factor *** markedly increases bone mineral density and has been proven to reduce the risk of ***,numerous adverse effects,notably hypocalcemia,are prevalent in patients with end-stage renal disease(ESRD).AIm To analyze the incidence and predictors of hypocalcemia caused by denosumab compared to control in patients with *** We conducted this study in accordance with the Preferred Reporting Items for Systematic Reviews and meta-analyses ***,Scopus,Cochrane Central,and EmBASE were systematically searched from inception through march *** original studies investigating the effects of denosumab on patients with ESRD compared to control were *** primary outcomes of our study were the incidence of mild,severe,and very severe *** outcomes included serum levels of intact parathyroid hormone,calcium,and *** results were pooled and analyzed using a random-effects *** Seven articles comprising 3240 patients were included in our *** treated with denosumab had a significantly increased incidence of mild hypocalcemia[risk ratio(RR):2.79;95%confidence interval(CI):0.99-7.91;P=0.05;I^(2)=37%]and of very severe hypocalcemia(RR:9.58;95%CI:1.58-57.98;P=0.01;I^(2)=49%).However,an increase in the occurrence of severe hypocalcemia was non-significant(RR:4.23;95%CI:0.47-38.34;P=0.20;I^(2)=96%).Alternatively,denosumab showed a significant decrease in serum intact parathyroid hormone[mean difference(mD):-433.20,95%CI:-775.12 to-91.28,I2=98%,P=0.01],while there was a non-significant decrease in phosphate(mD:-0.47,95%CI:-1.35 to 0.41,I^(2)=88%,P=0.30)and calcium levels(mD:-0.33,95%CI:-0.95 to 0.29,I^(2)=94%,P=0.29).CONCLUSION Our study demonstrated that denosumab is significantly associated with mild and very severe hypocalcemia in patients with ESRD making it necessary to detect and prevent this side effect of treatmen

关键词： Denosumab End-stage renal disease Hypocalcemia Parathyroid hormone Dialysis

Structural and mechanical properties of Al–C–N films deposited at room temperature by plasma focus device

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Chinese Physics B 2016年第7期25卷 299-304页

作者： Z A Umar R Ahmad R S Rawat m A Baig J siddiqui T Hussain National Centre for Physics Quaid-i-Azam University Campus Department of Physics GC University NSSE National Institute of Education Nanyang Technological University Centre for Advanced Studies in Physics GC University

The Al–C–N films are deposited on Si substrates by using a dense plasma focus（DPF） device with aluminum fitted central electrode（anode） and by operating the device with CH_4/N_2 gas admixture ratio of 1：1. XRD results verify the crystalline Al N（111） and Al_3CON（110） phase formation of the films deposited using multiple shots. The elemental compositions as well as chemical states of the deposited Al–C–N films are studied using XPS analysis, which affirm Al–N, C–C, and C–N bonding. The FESEm analysis reveals that the deposited films are composed of nanoparticles and nanoparticle agglomerates. The size of the agglomerates increases at a higher number of focus deposition shots for multiple shot depositions. Nanoindentation results reveal the variation in mechanical properties（nanohardness and elastic modulus）of Al–C–N films deposited with multiple shots. The highest values of nanohardness and elastic modulus are found to be about 11 and 185 GPa, respectively, for the film deposited with 30 focus deposition shots. The mechanical properties of the films deposited using multiple shots are related to the Al content and C–N bonding.

关键词： dense plasma focus XPS field emission scanning electron microscope elastic modulus

Tea beverage in chemoprevention and chemotherapy of prostate cancer

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Acta Pharmacologica Sinica 2007年第9期28卷 1392-1408页

作者： Imtiaz A siddiqui mohammad SALEEm Vaqar m ADHAmI mohammad ASIm Hasan mUKHTAR Department of Dermatology University of WisconsinMedical Sciences CenterRoom B-25 1300 University AvenueMadisonWisconsin 53706USA

Prostate cancer (PCa) is the most frequently diagnosed malignancy and the sec-ond leading cause of cancer-related deaths in American males with similar trendsin many western *** existing treatment approaches and surgical inter-vention have not been able to effectively cope with this dreaded *** reasons,it is necessary to intensify our efforts for a better understanding ofthe disease process and for the development of novel approaches for its preven-tion and *** on considerable evidence from in vivo and in vitro dataand epidemiological studies,in recent years the beverage tea has gained consid-erable attention for reducing the risk of several *** of the cancerpreventive effects of tea,especially green tea appear to be mediated by the polyphe-nols present *** evidence suggests that the incidence andoccurrence of PCa is lower in populations that consume tea *** evi-dence suggests that tea polyphenols could be extrapolated to optimize theirchemopreventive properties against *** represents an excellent candidatedisease for chemoprevention because it is typically diagnosed in men over 50years of age and therefore,even a modest delay in neoplastic development achievedthrough pharmacological or nutritional intervention could result in a substantialreduction in the incidence of clinically detectable *** this review weaddress the issue of possible use of tea,especially green tea,for the prevention aswell as treatment of PCa.

关键词： Green tea (-)epigallocatechin-3-gallate (-) epicatechin apoptosis androgen receptor PSA tumor xenograft epidemiology clinical studies

An investigation of non-Newtonian fluid flow due to metachronal beating of cilia in a tube

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International Journal of Biomathematics 2015年第2期8卷 29-51页

作者： A. m. siddiqui A. A. Farooq m. A. Rana Department of mathematics Pennsylvania State University York Campus York PA 17403-3398 USA Department of Basic Sciences Riphah International University Islamabad 44000 Pakistan Department of mathematics COmSATS Institute of Information Technology Tobe Camp Abbottabad Pakistan

The aim of this study is to explain theoretically the role of ciliary motion on the transport of epididymal fluid through the ductus efferentes of the male reproductive track. For this purpose, a mathematical model has been developed for the flow of a non-Newtonian fluid in an axisymmetric tube due to metachronal wave of cilia motion for the more realistic consequences. Carreau viscous fluid model is considered to see the rheological effects on the pumping characteristics of the flow. Regular perturbation method has been employed to obtain the analytical expressions for the stream function, the velocity field and a relation between the pressure difference and the volume flow rate. It is found that the volume flow rate is influenced significantly by Weissenberg number We and the cilia length parameter ε. The computational results are presented graphically to see the effects of various physical parameters. Finally, the analysis is applied and compared with the observed value of the flow rate of spermatic fluid in the ductus efferentes of the male reproductive track. The volume flow rate is reported closed to the estimated value 6 × 10^-3 ml/h in the human ductus efferentes when We = 0.5 and e is near by 0.25.

关键词： Cilia-induced motion axisymmetric tube metachronal wave Carreau fluid analytic solutions pumping and trapping.