Biologically-inspired transport of solid spherical nanoparticles in an electrically-conducting viscoelastic fluid with heat transfer

Bio-inspired pumping systems exploit a variety of mechanisms including peristalsis to achieve more efficient propulsion. Non-conducting, uniformly dispersed, spherical nano-sized solid particles suspended in viscoelastic medium forms a complex working matrix. Electromagnetic pumping systems often employ complex working fluids. A simulation of combined electromagnetic bio-inspired propulsion is observed in the present article. Currents formation has increasingly more applications in mechanical and medical industries. A mathematical study is conducted for magnetohydrodynamic pumping of a bi-phase nanofluid coupled with heat transfer in a planar channel. Two-phase model is employed to separately identity the effects of solid nanoparticles. Base fluid employs Jeffery’s model to address viscoelastic characteristics. The model is simplified using of long wavelength and creeping flow approximations. The formulation is taken to wave frame and non-dimensionalize the equations. The resulting boundary value problem is solved analytically, and exact expressions are derived for the fluid velocity, particulate velocity, fluid/particle temperature, fluid and particulate volumetric flow rates, axial pressure gradient and pressure rise. The influence of volume fraction density, Prandtl number, Hartmann number, Eckert number and relaxation time on flow and thermal characteristics is evaluated in detail. The axial flow is accelerated with increasing relaxation time and greater volume fraction whereas it is decelerated with greater Hartmann number. Both fluid and particulate temperature are increased with increment in Eckert and Prandtl number whereas it is reduced when the volume fraction density increases. With increasing Hartmann, number pressure rise is reduced. Furthermore, pressure is reduced with greater relaxation time in the retrograde pumping region whereas it is elevated in the co-pumping and free pumping regions. The number of the trapped boluses is decreased whereas the quantity of boluses increases with a rise in volume fraction density of particles

Coordination of opposing sex-specific and core muscle groups regulates male tail posture during Caenorhabditis elegans male mating behavior

Background To survive and reproduce, animals must be able to modify their motor behavior in response to changes in the environment. We studied a complex behavior of Caenorhabditis elegans, male mating behavior, which provided a model for understanding motor behaviors at the genetic, molecular as well as circuit level. C. elegans male mating behavior consists of a series of six sub-steps: response to contact, backing, turning, vulva location, spicule insertion, and sperm transfer. The male tail contains most of the sensory structures required for mating, in addition to the copulatory structures, and thus to carry out the steps of mating behavior, the male must keep his tail in contact with the hermaphrodite. However, because the hermaphrodite does not play an active role in mating and continues moving, the male must modify his tail posture to maintain contact. We provide a better understanding of the molecular and neuro-muscular pathways that regulate male tail posture during mating. Results Genetic and laser ablation analysis, in conjunction with behavioral assays were used to determine neurotransmitters, receptors, neurons and muscles required for the regulation of male tail posture. We showed that proper male tail posture is maintained by the coordinated activity of opposing muscle groups that curl the tail ventrally and dorsally. Specifically, acetylcholine regulates both ventral and dorsal curling of the male tail, partially through anthelmintic levamisole-sensitive, nicotinic receptor subunits. Male-specific muscles are required for acetylcholine-driven ventral curling of the male tail but dorsal curling requires the dorsal body wall muscles shared by males and hermaphrodites. Gamma-aminobutyric acid activity is required for both dorsal and ventral acetylcholine-induced curling of the male tail and an inhibitory gamma-aminobutyric acid receptor, UNC-49, prevents over-curling of the male tail during mating, suggesting that cross-inhibition of muscle groups helps maintain proper tail posture. Conclusion Our results demonstrated that coordination of opposing sex-specific and core muscle groups, through the activity of multiple neurotransmitters, is required for regulation of male tail posture during mating. We have provided a simple model for regulation of male tail posture that provides a foundation for studies of how genes, molecular pathways, and neural circuits contribute to sensory regulation of this motor behavior

Numerical study of slip and radiative effects on magnetic Fe3O4-water-based nanofluid flow from a nonlinear stretching sheet in porous media with Soret and Dufour diffusion

Increasingly sophisticated techniques are being developed for the manufacture of functional nanomaterials. A growing interest is also developing in magnetic nanofluid coatings which contain magnetite nanoparticles suspended in a base fluid and are responsive to external magnetic fields. These nanomaterials are “smart” and their synthesis features high-temperature environments in which radiative heat transfer is present. Diffusion processes in the extruded nanomaterial sheet also feature Soret and Dufour (cross) diffusion effects. Filtration media are also utilized to control the heat, mass and momentum characteristics of extruded nanomaterials and porous media impedance effects arise. Magnetite nanofluids have also been shown to exhibit hydrodynamic wall slip which can arise due to non-adherence of the nanofluid to the boundary. Motivated by the multi-physical nature of magnetic nanomaterial manufacturing transport phenomena, in this paper, we develop a mathematical model to analyze the collective influence of hydrodynamic slip, radiative heat flux and cross-diffusion effects on transport phenomena in ferric oxide (Fe3O4-water) magnetic nanofluid flow from a nonlinear stretching porous sheet in porous media. Hydrodynamic slip is included. Porous media drag is simulated with the Darcy model. Viscous magnetohydrodynamic theory is used to simulate Lorentzian magnetic drag effects. The Rosseland diffusion flux model is employed for thermal radiative effects. A set of appropriate similarity transformation variables are deployed to convert the original partial differential boundary value problem into an ordinary differential boundary value problem. The numerical solution of the coupled, multi-degree, nonlinear problem is achieved with an efficient shooting technique in MATLAB symbolic software. The physical influences of Hartmann (magnetic) number, Prandtl number, Richardson number, Soret (thermo-diffusive) number, permeability parameter, concentration buoyancy ratio, radiation parameter, Dufour (diffuso-thermal) parameter, momentum slip parameter and Schmidt number on transport characteristics (e.g. velocity, nanoparticle concentration and temperature profiles) are investigated, visualized and presented graphically. Flow deceleration is induced with increasing Hartmann number and wall slip, whereas flow acceleration is generated with greater Richardson number and buoyancy ratio parameter. Temperatures are elevated with increasing Dufour number and radiative parameter. Concentration magnitudes are enhanced with Soret number, whereas they are depleted with greater Schmidt number. Validation of the MATLAB computations with special cases of the general model is included. Further validation with generalized differential quadrature (GDQ) is also included

Computational framework of magnetized MgO-Ni/water based stagnation nanoflow past an elastic stretching surface : application in solar energy coatings

In this article, motivated by novel nanofluid solar energy coating systems, a mathematical model of hybrid Magnesium oxide (MgO)-nickel (Ni) nanofluid magnetohydrodynamic (MHD) stagnation point flow impinging on a porous elastic stretching surface in a porous medium is developed. The hybrid nanofluid is electrically conducting and magnetic Reynolds number is sufficiently large to invoke induced magnetic field. A Darcy model is adopted for the isotropic, homogenous porous medium. The boundary conditions account for the impacts of velocity slip and thermal slip. Heat generation (source)/absorption (sink) and also viscous dissipation effects are included. The mathematical formulation has been performed with the help of similarity variables and the resulting coupled nonlinear dimensionless ordinary differential equations have been solved numerically with the help of shooting method. To test the validity of the current results and the convergence of the solutions, a numerical comparison with previously published results is included. Numerical results are plotted for the effect of emerging parameters on velocity, temperature, magnetic induction, skin friction and Nusselt number. With increment in nanoparticle volume fraction of both MgO and Ni nanoparticles, the temperature and thermal boundary layer thickness of the nanofluid are elevated. An increase in porous medium parameter (Darcy number), velocity slip and thermal Grashof number all enhance the induced magnetic field. Initially increment in nanoparticle volume fraction for both MgO and Ni suppress the magnetic induction near the wall although subsequently further from the wall this effect is reversed. Temperature is enhanced with heat generation whereas it is depleted with heat absorption and thermal slip effects. Overall excellent thermal enhancement is achieved by the hybrid nanofluid

Use of Cinnamon and Black Cumin as Effective Alternative of Antibiotics on Growth Performance of Broiler

ABSTRACT The experiment was conducted with Cobb-500 broiler strain. For this purpose 360 broiler chicks were purchased from Kazi Hatchery, Gazipur, Dhaka. The experiment was conducted in the month of November and December 2013 for 28 days at SAU Poultry farm. There were six treatments, Such as, T1: 0.25 % of cinnamon/ black cumin; T2: 0.50 % of cinnamon/ black cumin; T3: 0.75 % of cinnamon/ black cumin; T4: 1.0 % of cinnamon/ black cumin; T5: Basal Diets + Antibiotics and T6: Control (Basal Diet with no antibiotics or cinnamon/ black cumin) The number of replications was three for each treatment. So the total number of replications was 18 units which were randomly selected. Each replication had 10 chicks. Two experiment was conducted both for Cinnamon and Black Cumin at same time. The best common cinnamon and black cumin dose was 0.50% for feed consumption. For both cinnamon and black cumin, the height LW was found in 0.75 % level. The FCR results indicated that any dose of cinnamon and black cumin can be used for best FCR. The analytical results of mortality both for cinnamon and black cumin showed no significant difference (P>0.05) within them. So considering market price 0.25% or 0.50% dose of cinnamon or black cumin can be used for best survivevality. Similarly, lower doses of cinnamon and black cumin were suitable to keep lower blood glucose and blood cholesterol level. SP ratio for Gumboro disease were significantly higher (P<0.05) in all cinnamon supplementation groups which had positive effects on immune responses, whereas higher doses of black cumin showed positive effects on immune responses. SP ratio for Newcastle disease were significantly higher (P<0.05) in all cinnamon supplementation groups which had positive effects on immune responses. But, cumin supplementation groups had not positive effects on immune responses

Numerical investigation of radiative optically-dense transient magnetized reactive transport phenomena with cross diffusion, dissipation and wall mass flux effects

High temperature electromagnetic materials fabrication systems in chemical engineering require ever more sophisticated theoretical and computational models for describing multiple, simultaneous thermophysical effects. Motivated by this application, the present article addresses transient magnetohydrodynamic heat and mass transfer in chemically-reacting fluid flow from an impulsively-started vertical perforated sheet. Thermal radiation flux, internal heat generation (heat source), Joule magnetic heating (Ohmic dissipation), thermo-diffusive and diffuso-thermal (i.e. cross-diffusion) effects and also viscous dissipation are incorporated in the mathematical model. To facilitate numerical solutions of the coupled, nonlinear boundary value problem, non-similar transformations are employed and the partial differential conservation equations are normalized into a dimensionless system of momentum, energy and concentration equations with associated boundary thermal conditions. An implicit finite difference method (FDM) is utilized to solve the unsteady equations. Verification of the FDM solutions for dimensionless velocity, temperature and concentration functions is achieved with a variational finite element method code (MAGNETO-FEM) and also a network simulation method code (MAG-PSPICE). The influence of the emerging thermo-physical parameters on transient velocity, temperature, concentration, wall shear stress, Nusselt number and Sherwood number is elaborated. The flow is accelerated with increasing thermal radiative flux, Eckert number, heat generation and Soret number whereas the flow is decelerated with greater wall suction, heat absorption, magnetic field and Prandtl number. Temperatures are also observed to be elevated with magnetic parameter, radiation heat transfer, Dufour number, heat generation (source) and Eckert number with the contrary effects computed for increasing suction parameter or Prandtl number. The species concentration is enhanced with Soret number and generative chemical reaction whereas it is depressed with greater wall suction, Schimidt number and destructive chemical reaction paramete

Effects of Papaya Leaf (Carica papaya) and Black Cumin (Nigella sativa) as an Alternative to Antibiotics on Production Index and Hematological Indicators of Broiler Chicken

ABSTRACT The purpose of the study was to determine the effectiveness of dietary supplements of papaya leaf meal (Carica papaya) and black cumin (Nigella sativa) seeds on the production index and hematological status of commercial broiler chicken. T1 (Control), T2 (antibiotic), T3 (2% PLM: Papaya Leaf Meal), T4 (1% BCS: Black Cumin Seed) and T5 (1% of each PLM & BCS) were the five treatment groups that the 150day-old Cobb 500 straight run chicks were randomly assigned. Ten chicks were used in each of the three replications of each treatment. The findings demonstrated that feeding broilers supplements of PLM and BCS did not significantly (p>0.05) affect feed consumption (FC) (g), final live weight (g) and feed conversion ratio (FCR) when compared to the control and antibiotic group. FC was found to be numerically (p>0.05) higher in the control group than in the other groups. However, the T3 group of birds given 2% PLM had superior ultimate live weight and an improved FCR value compared to antibiotic, control, and the values of the other groups, which were statistically insignificant (p>0.05). The relative weight of the spleen in various groups was unaffected (p>0.05) by dietary supplementation with PLM and BCS. But the T3 (2% PLM) group had significantly (p<0.05) increased bursa weight (g). The concentrations of glucose and cholesterol were similar across all groups (p>0.05), while the group receiving 2% PLM supplements had relatively lower cholesterol levels (mg/dl). Moreover, the supplemented groups with PLM and BCS revealed a significant (p<0.05) increase in the hematological parameters red blood cell (RBC), white blood cell (WBC), lymphocyte, and packed cell volume (PCV) as compared to the antibiotic and control groups. The final live weight, FCR, immune organ weight, and blood indices were all improved in birds fed a meal supplemented with 2% PLM, leading to superior results

Computation of non-isothermal thermo-convective micropolar fluid dynamics in a Hall MHD generator system with non-linear distending wall

A theoretical model for steady non-isothermal convective heat transfer in non-Newtonian magnetized micropolar gas flow from a non-linear stretching/contracting wall in the presence of strong magnetic field is presented, as a simulation of an MHD (magnetohydrodynamic) Hall energy generator. Subsonic flow is considered, and compressibility effects neglected. The strength of the magnetic field which is applied in the general case obliquely to the wall is sufficient to invoke the collective effects of Hall current and Ohmic heating (Joule dissipation). Viscous heating is also included in the energy balance. Deploying similarity transformations, the governing equations are normalized into nonlinear ordinary differential equations with associated boundary conditions. The non-linear boundary value problem thus posed is then solved computationally with Nachtsheim-Swigert iteration technique along with the fourth-fifth order Runge-Kutta integration method (RKM). Verification of solutions is obtained with the semi-analytical Homotopy analysis method (HAM). Further validation is conducted with the semi-numerical Adomian Decomposition Method (ADM). In both cases excellent agreement is obtained with the Runge-Kutta shooting quadrature solutions. Additional validation is conducted with earlier Newtonian studies in the absence of micropolar, Hall current and dissipation effects. The influence of local Grashof number, local Hartmann number, Eringen microrotational parameter, Eringen coupling vortex parameter, Prandtl number and Eckert number on non-dimensional velocity components (primary, secondary and angular) and temperature within the boundary layer are graphically illustrated and interpreted at length. Furthermore, the effects of the thermophysical (e.g. non-isothermal power law index), electromagnetic parameters (e.g. Hall parameter) and geometric parameter (wall extension/contraction parameter) on the skinfriction coefficient (i.e. primary and secondary shear stress and wall couple stress) and surface heat transfer rate (Nusselt number) are evaluated. The study is relevant to near wall transport phenomena in novel MHD Hall power generators

Differential transform solution for hall and ion slip effects on radiative-convective casson flow from a stretching sheet with convective heating

Magnetohydrodynamic (MHD) materials processing is becoming increasingly popular in the 21st century since it offers significant advantages over conventional systems including improved manipulation of working fluids, reduction in wear and enhanced sustainability. Motivated by these developments, the present work develops a mathematical model for Hall and Ion slip effects on non-Newtonian Casson fluid dynamics and heat transfer towards a stretching sheet with a convective heating boundary condition under a transverse magnetic field. The governing conservation equations for mass, linear momentum and thermal (energy) are simplified with the aid of similarity variables and Ohm’s law. The emerging nonlinear coupled ordinary differential equations are solved with an analytical technique known as the differential transform method (DTM). The impact of different emerging parameters is presented and discussed with the help of graphs and tables. Generally aqueous electro-conductive polymers are considered for which a Prandtl number of 6.2 is employed. With increasing Hall parameter and ion slip parameter the flow is accelerated whereas it is decelerated with greater magnetic parameter and rheological (Casson) fluid parameter. Skin friction is also decreased with greater magnetic field effect whereas it is increased with stronger Hall parameter and ion slip parameter values

Xylanase and β-xylosidase production by Aspergillus ochraceus: new perspectives for the application of wheat straw autohydrolysis liquor

The xylanase biosynthesis is induced by its substrate—xylan. The high xylan content in some wastes such as wheat residues (wheat bran and wheat straw) makes them accessible and cheap sources of inducers to be mainly applied in great volumes of fermentation, such as those of industrial bioreactors. Thus, in this work, the main proposal was incorporated in the nutrient medium wheat straw particles decomposed to soluble compounds (liquor) through treatment of lignocellulosic materials in autohydrolysis process, as a strategy to increase and undervalue xylanase production by Aspergillus ochraceus. The wheat straw autohydrolysis liquor produced in several conditions was used as a sole carbon source or with wheat bran. The best conditions for xylanase and β-xylosidase production were observed when A. ochraceus was cultivated with 1% wheat bran added of 10% wheat straw liquor (produced after 15 min of hydrothermal treatment) as carbon source. This substrate was more favorable when compared with xylan, wheat bran, and wheat straw autohydrolysis liquor used separately. The application of this substrate mixture in a stirred tank bioreactor indicated the possibility of scaling up the process to commercial production.This work was supported by Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP/Brazil), Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq/Brazil), National System for Research on Biodiversity (SISBIOTA-Brazil, CNPq 563260/2010-6/FAPESP no. 2010/52322-3), and Fundacao para a Ciencia e a Tecnologia (FCT/Portugal)