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1.
Comput Methods Programs Biomed ; 200: 105926, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33450503

ABSTRACT

MOTIVATIONS: Now-a-days in medical science, the transport study of biological fluids through non-uniform vessels are going to increase due to their close relation to the reality. Motivated through such type of complex transportation, the current study is presented of cilia hydro-dynamics of an aqueous electrolytic viscous fluid through a non-uniform channel under an applied axial electric field. Mathematical Formulations: Because of the complexity shape and nature of flow channel, we have used curvilinear coordinates in the derivation of continuity and momentum equationsin a fixed frame of reference. A linear transformation is used to renovate the flow system of equations from fixed (laboratory) to moving (wave) frame. For further simplification, the dimensionless variables are introduced to make the flow system of equations into the dimensionless form and at last convert these equations in term of stream function by using the mathematical terminologies of streamlines. The whole analysis is performed under (low Reynolds number) creeping phenomena and long wavelength approximation, respectively. Additionally, small ionic Peclet number and Debye-Huckel linearization are used to simplify the Nernst-Planck and Poisson-Boltzmann equations. The BVP4C technique is used to obtain the numerical solution for velocity distribution, pressure gradient, pressure rise and stream function through MATLAB. MAIN OUTCOMES: The amplitude of velocity distribution is increased (decreased) at larger values of non-uniform parameter (cilia length). The non-uniform parameter played a vital role not only in the enhancement of circulation at the upper half of the channel but also the length of bolus increased. Results of straight channel are gained for larger value of the dimensionless radius of curvature parameter as well as cilia length.


Subject(s)
Body Fluids , Cilia , Kinetics , Peristalsis , Viscosity
2.
Comput Methods Programs Biomed ; 190: 105347, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32062089

ABSTRACT

BACKGROUND AND OBJECTIVE: The scrutiny of nonlinear convected flow aspect has continuously appealed researchers attention because of its ample demands in processes like heat exchangers, building insulation, crystal growth, insulation of nuclear reactor, food processing, solar energy and electronic element chilling etc. Taking into consideration the aforesaid utilizations, we modeled differential type (second-grade) nanoliquid considering non-linear mixed convection. The considered differential type nonlinear model elaborates viscoelasticity (elastic and viscous) characteristics. Furthermore the thermal systems emphases on transportation of heat and irreversibility reduction. Especially, evaluating the systems via thermodynamic second relation is essential with the purpose of finding a standard communication between power input prerequisite and heat transference augmentation. METHOD: Formulated non-dimensional problem is non-linear subject to the assumptions (i.e., Non-linear mixed convection, magnetic field, viscous dissipation, double stratification, Joule heating and convective conditions). Analytic simulations for modeled non-linear systems is not possible. Hence we considered bvp4c scheme for non-linear analysis. CONCLUSIONS: Velocity [Formula: see text] of second grade (non-Newtonian) fluid intensifies for larger estimations of R* and λ* whereas it dwindles for M. Temperature of nanoliquid deteriorates with S1 while (θ(η)) rises against Ec. Entropy generation (EG) and (BN) (Bejan number) significantly affected by physical parameters M, α2 and Br.


Subject(s)
Entropy , Magnetic Fields , Nanostructures , Thermodynamics , Algorithms , Animals , Convection , Models, Statistical
3.
Comput Methods Programs Biomed ; 190: 105363, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32062091

ABSTRACT

Background In this research communication, entropy optimized Darcy-Forchheimer flow with magnetohydrodynamic over a stretched surface is considered. Here Molybdenum disulfide (MOS2) and Silicon dioxide (SiO2) are taken as a nanoparticles and Propylene glycol as a continuous phase liquid. Electrically conducting fluid is considered and flow is generated via stretched surface of sheet. The total entropy rate which is depends on four types of irreversibilities i.e., heat transfer, porosity, fluid friction and dissipation) is calculated via second law of thermodynamics. The energy expression is mathematically modeled and discussed subject to heat generation/absorption, dissipation, thermal radiation and Joule heating. Furthermore, temperature dependent viscosity is accounted. Method The nonlinear PDE's (partial differential equations) are first changed to ODE's (ordinary differential equations) through implementation of appropriate similarity variables (transformations). The numerical results of ordinary ones are computed via Built-In-Shooting method. The results for the flow field, temperature, skin friction, Nusselt number and entropy generation are discussed against various sundry flow parameters graphically. Results Salient characteristics of sundry flow parameters on the entropy generation rate, velocity, Bejan number, gradients of velocity, gradient of temperature and temperature are examined and display graphically. The results are computed for both nanoparticles. From obtained results it is observed that temperature field increases versus higher thermal Biot number for both nanoparticles. It is also observed that the thermal field is more in presence of Molybdenum disulfide as compared to Silicon dioxide, because the thermal conductivity of Molybdenum disulfide is higher than Silicon dioxide. Entropy generation and Bejan number show contrast impact versus higher estimations of Brinkman number versus both nanoparticles.


Subject(s)
Disulfides , Entropy , Hydrodynamics , Molybdenum , Nanostructures , Silicon Dioxide , Algorithms , Computer Simulation , Convection , Viscosity
4.
Comput Methods Programs Biomed ; 190: 105355, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32058189

ABSTRACT

BACKGROUND: Peristaltic is a basic way of fluid transportation in physiology, engineering and nuclear industry. Importance of peristalsis is due to its contraction and compulsion property of symmetric and asymmetric type channel walls. Another beauty of this mechanism is that the channel walls propagates and push the material along the tube/conduit channel walls. This mechanism shows its presence in physiology while food particles are transferred through esophagus and stomach, urine through intestines, spermatoza transportation in reproductive tract. In industry it is found in roller and finger pumps, drug delivery and various nuclear materials e.g. toxic, corrosive, noxious etc. Magnetic field in peristalsis is found helpful in treatment of various treatments using magnets. Actually earth and human body as a whole comprises of magnetic and electric fields. The medical specialists found that unbalances of electromagnetic field in human body is the reason for emotional and physical disturbance. In addition it has significant and potential utilizations in modification of medical, industrial and chemical, procedures for example MRI, evaporation, convection, thermoregulation, MHD throttles, and in various types of tumor treatments. Entropy production work out irreversibility in complex systems which are frequently encountered in industrial mechanisms. In view of that, this methodology is effectually implemented in distinct technological applications covering porous media, propulsion ducts, electronic cooling, turbo-machinery and combustion. METHOD: Modelled flow mechanism is nonlinear and coupled due to considered assumptions (i.e. nanofluid, nonlinear porous channel, mixed convection, variable viscosity and thermal conductivity, activation energy and chemical reaction). Such nonlinear and coupled system is difficult to tackle analytically. Thus to obtain the solution we employed RK algorithm for numerical simulations. RESULTS: Stronger magnetic parameter shows resistive characteristics to the flow field. Nonlinear Darcy medium assists the fluid motion at channel center and resits at walls vicinity. Variable characteristics of thermal conductivity moderate the soak or disperse up heat ability which corresponds to temperature reduction. Thermal slip quantity increase the temperature whereas concentration slip deduct the concentration of Carreau nanomaterial. Entropy and Bejan number shows maximum response for higher dissipation estimations. Brownian and thermopherotic motions aspects has reverse impact on nanomaterial concentration. CONCLUSION: Entropy and Bejan number deduces for higher variable thermal conductivity values. Carreau material variable enhance the entropy of the system as a whole.


Subject(s)
Hot Temperature , Hydrodynamics , Nanostructures , Peristalsis , Thermal Conductivity , Viscosity , Algorithms , Humans
5.
Comput Methods Programs Biomed ; 190: 105362, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32032806

ABSTRACT

Hydromagnetic second order velocity slip flow of viscous material with nonlinear mixed convection towards a stretched rotating disk is numerically examined here. Important slip mechanism of Buongiorno's nanofluid model i.e., Brownian motion and thermophoretic diffusion is incorporated in the mathematical modeling. Heat transport aspects are examined via Joule heating, thermal radiation and dissipation. Convective conditions at the stretchable surface of disk is implemented for the heat transport analysis. Chemical reaction subject to activation energy is also considered. Through appropriate transformations and shooting method the outcomes are computed and demonstrated graphically. The flow field, temperature, surface drag force, concentration and Nusselt number are deliberated subject to pertinent parameters. Total entropy rate is obtained. The outcomes show that magnetic field significantly affects the flow field as well as entropy rate.


Subject(s)
Convection , Entropy , Hydrodynamics , Magnetic Fields , Algorithms , Computer Simulation , Nanotechnology
6.
Korean J Parasitol ; 50(1): 37-43, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22451732

ABSTRACT

Although schistosomicidal drugs and other control measures exist, the advent of an efficacious vaccine remains the most potentially powerful means for controlling this disease. In this study, native fatty acid binding protein (FABP) from Fasciola gigantica was purified from the adult worm's crude extract by saturation with ammonium sulphate followed by separation on DEAE-Sephadex A-50 anion exchange chromatography and gel filtration using Sephacryl HR-100, respectively. CD1 mice were immunized with the purified, native F. gigantica FABP in Freund's adjuvant and challenged subcutaneously with 120 Schistosoma mansoni cercariae. Immunization of CD1 mice with F. gigantica FABP has induced heterologous protection against S. mansoni, evidenced by the significant reduction in mean worm burden (72.3%), liver and intestinal egg counts (81.3% and 80.8%, respectively), and hepatic granuloma counts (42%). Also, it elicited mixed IgG(1)/IgG(2b) immune responses with predominant IgG1 isotype, suggesting that native F. gigantica FABP is mediated by a mixed Th1/Th2 response. However, it failed to induce any significant differences in the oogram pattern or in the mean granuloma diameter. This indicated that native F. gigantica FABP could be a promising vaccine candidate against S. mansoni infection.


Subject(s)
Fasciola/chemistry , Fatty Acid-Binding Proteins/administration & dosage , Helminth Proteins/administration & dosage , Schistosoma mansoni/physiology , Schistosomiasis mansoni/prevention & control , Animals , Antibodies, Helminth/immunology , Fatty Acid-Binding Proteins/immunology , Fatty Acid-Binding Proteins/isolation & purification , Female , Helminth Proteins/immunology , Helminth Proteins/isolation & purification , Humans , Immunization , Mice , Mice, Inbred Strains , Schistosoma mansoni/immunology , Schistosomiasis mansoni/immunology , Schistosomiasis mansoni/parasitology
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