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Considering the Navier Stokes equations paired with the heat equation for ferrohydrodynamic flow of magnetic nanofluid amidst two rotating porous disks, nothing is known on the significance of geothermal viscosity for the magnetic fluid flow between co-rotating porous surfaces. The current analysis considers the effects of changing viscosity and thermal radiation. Additionally, the stretching and angular velocities of the two disks differ. The flow model's estimated basic equations are transformed into nondimensional ordinary differential equations (ODEs) with the proper transformation before being numerically solved using Maple's built-in BVP Midrich approach. For velocity and temperature fields, the effects of active flow parameters such as the depth-dependent viscosity variation parameter, ferro-hydrodynamics interaction parameter, Reynolds number, Prandtl number, Darcy number, Eckert number, and radiation parameter are discussed. It is worth noticing that the temperature field tends to decline as the Darcy parameter is higher estimated. It is worth concluding that there exists a high fluctuating viscosity around the lower disk, the magnitude of horizontal velocity decreased, but vertical velocity increased everywhere else. Furthermore, skin friction becomes more valuable at higher Reynolds numbers and porosity estimates. [ABSTRACT FROM AUTHOR]

An investigation has been carried out on heat and mass transport phenomena for mixed-convection flow over a vertically non-Darcy Forchheimer porous stretching/shrinking sheet considering the Soret - Dufour effects. With consideration of the appropriate similarity framework, the fundamental governing flow equations are converted into a system of non-dimensional equations. The bvp4c, a built-in solver of MATLAB software, is utilized to compute the numerical results of the flow problem. The present model is validated with previously published literature. The impacts of several related flow parameters on velocity, temperature, and concentration profiles have been displayed graphically. Also, the mass and heat transfer rates along with the coefficients of skin friction are calculated and discussed numerically. It is found that an increment in the thermal radiation parameter increases the fluid temperature, and the concentration gradient boosts up for the enhancement of the Soret number. [ABSTRACT FROM AUTHOR]

An attempt has been made to describe the effects of geothermal viscosity with viscous dissipation on the three dimensional time dependent boundary layer flow of magnetic nanofluids due to a stretchable rotating plate in the presence of a porous medium. The modelled governing time dependent equations are transformed a from boundary value problem to an initial value problem, and thereafter solved by a fourth order Runge-Kutta method in MATLAB with a shooting technique for the initial guess. The influences of mixed temperature, depth dependent viscosity, and the rotation strength parameter on the flow field and temperature field generated on the plate surface are investigated. The derived results show direct impact in the problems of heat transfer in high speed computer disks (Herrero et al. [1]) and turbine rotor systems (Owen and Rogers [2]).

The current study computationally investigates the thermally radiative incompressible flow of hybrid nanofluid induced by a radially stretchable rotating disk with entropy generation analysis. The temperature-dependent viscosity of hybrid nanofluid, stretching of the disk, chemical reaction, Joule, and viscous dissipation effects are incorporated in the formulation of the mathematical flow model. In this study, Karman's transformations are used to convert the governing equations of partial derivative form into their ordinary derivative form, which is evaluated numerically together with boundary conditions using the BVP Midrich technique built-in Maple software. The impacts of variable viscosity parameter, magnetic field parameter, radiation parameter, Eckert number, Prandtl number, Biot Number, and chemical reaction parameter on flow-field factors and entropy generation rate are presented graphically. The outcomes indicate that higher estimations of magnetic field parameter and entropy generation rate increase the velocity distribution. Also, an increment in Schmidt number and chemical reaction parameter diminishes hybrid fluid concentration, and a higher magnetic field parameter maximizes the same. This study is significant in industrial thermal management and heat transport increment in renewable energy systems. [ABSTRACT FROM AUTHOR]

The present study investigates the Marangoni convective fluid flow over a rotating disk with an inclined magnetic field and in the presence of a nonuniform heat source when the disk moves upward/downward with nonconstant velocity with the incorporation of the second law of thermodynamics. The Keller‐box method is applied to the reduced system of equations to draw graphical illustrations. The study of these illustrations to examine the effects of involved pertinent parameters, like, magnetic field, Marangoni number, angle of inclination, vertical disk movement parameter, heat source, and disk rotation, on velocity and temperature profiles, reveals some interesting findings. From the analysis, it can be concluded that the skin friction coefficient increases with more angle of inclination and the Marangoni number with the reverse trend in case of vertical disk movement. Also, the Marangoni number and vertical disk motion diminish the Nusselt number with a positive effect in the case of more angle of inclination. The rate of entropy generation is enhanced with the temperature ratio parameter while it diminishes with the inclined magnetic field of any strength. The current study in its reduced form is in excellent agreement with earlier published work to ensure the validity of the used numerical scheme. [ABSTRACT FROM AUTHOR]

Influenza is a viral infection that affects human respiratory system: lungs, throat, nose etc. Influenza virus spreads from person to person by sneezing, coughing as well as the fluid medium. Further, the virus is carried to various parts of the human body to infect tissues during swallowing, breathing, drinking. In the present model, we study the diffusion of H1N1 virus in the viscous fluid medium via saliva which will help to predict the spread of the virus particles in the esophagus. According to that, a mathematical model is developed to simulate the nature of Swine Influenza virus through the saliva driven by the natural pumping mechanism. The BBO equation is considered for simulation of progression of virus particles in cervical esophagus. The impacts of fluid (saliva viscosity), and virus particle diameter have been analyzed and addressed the significance of various pertinent physical parameters. [ABSTRACT FROM AUTHOR]

Genes that are primarily expressed in cochlear glia-like supporting cells (GLSs) have not been clearly associated with progressive deafness. Herein, we present a deafness locus mapped to chromosome 3p25.1 and an auditory neuropathy spectrum disorder (ANSD) gene, TMEM43, mainly expressed in GLSs. We identify p.(Arg372Ter) of TMEM43 by linkage analysis and exome sequencing in two large Asian families segregating ANSD, which is characterized by inability to discriminate speech despite preserved sensitivity to sound. The knock-in mouse with the p.(Arg372Ter) variant recapitulates a progressive hearing loss with histological abnormalities in GLSs. Mechanistically, TMEM43 interacts with the Connexin26 and Connexin30 gap junction channels, disrupting the passive conductance current in GLSs in a dominant-negative fashion when the p.(Arg372Ter) variant is introduced. Based on these mechanistic insights, cochlear implant was performed on three subjects, and speech discrimination was successfully restored. Our study highlights a pathological role of cochlear GLSs by identifying a deafness gene and its causal relationship with ANSD. [ABSTRACT FROM AUTHOR]

Astrocytic Ca2+ fluctuations associated with functional hyperemia have typically been measured from large cellular compartments such as the soma, the whole arbor and the endfoot. The most prominent Ca2+ event is a large magnitude, delayed signal that follows vasodilation. However, previous work has provided little information about the spatio-temporal properties of such Ca2+ transients or their heterogeneity. Here, using an awake, in vivo two-photon fluorescence-imaging model, we performed detailed profiling of delayed astrocytic Ca2+ signals across astrocytes or within individual astrocyte compartments using small regions of interest next to penetrating arterioles and capillaries along with vasomotor responses to vibrissae stimulation. We demonstrated that while a 5-s air puff that stimulates all whiskers predominantly generated reproducible functional hyperemia in the presence or absence of astrocytic Ca2+ changes, whisker stimulation inconsistently produced astrocytic Ca2+ responses. More importantly, these Ca2+ responses were heterogeneous among subcellular structures of the astrocyte and across different astrocytes that resided within the same field of view. Furthermore, we found that whisker stimulation induced discrete Ca2+ "hot spots" that spread regionally within the endfoot. These data reveal that astrocytic Ca2+ dynamics associated with the microvasculature are more complex than previously thought, and highlight the importance of considering the heterogeneity of astrocytic Ca2+ activity to fully understanding neurovascular coupling. [ABSTRACT FROM AUTHOR]