Comparative appraisal of mono and hybrid nanofluid flows comprising carbon nanotubes over a three-dimensional surface impacted by Cattaneo-Christov heat flux.

Carbon nanotubes (CNTs) are nanoscale tubes made of carbon atoms with unique mechanical, electrical, and thermal properties. They have a variety of promising applications in electronics, energy storage, and composite materials and are found as single-wall carbon nanotubes (SWCNTs) and double-wall carbon nanotubes (DWCNTs). Considering such alluring attributes of nanotubes, the motive of the presented flow model is to compare the thermal performance of magnetohydrodynamic (MHD) mono (SWCNTs)/Ethylene glycol) and hybrid (DWCNTs- SWCNTs/Ethylene glycol) nanofluids over a bidirectional stretching surface. The thermal efficiency of the proposed model is gauged while considering the effects of Cattaneo-Christov heat flux with prescribed heat flux (PHF) and prescribed surface temperature (PST). The flow is assisted by the anisotropic slip at the boundary of the surface. The system of partial differential equations (PDEs) is converted into a nonlinear ordinary differential system by the use of similarity transformations and handled using the bvp4c numerical technique. To depict the relationship between the profiles and the parameters, graphs, and tables are illustrated. The significant outcome revealed that the fluid temperature rises in the scenario of both PST and PHF cases. In addition, the heat transfer efficiency of the hybrid nanoliquid is far ahead of the nanofluid flow. The truthfulness of the envisioned model in the limiting scenario is also given.

An Incidental Finding of Asymptomatic Gastric Diverticula.

Gastric diverticula (GD) are the rarest of the gastrointestinal diverticula and are characterized by protrusions of the stomach wall, that can either be congenital or acquired. Despite the fact that the majority of GD are asymptomatic and are detected inadvertently during endoscopy or gastrointestinal (GI) series studies, they might present with a variety of symptoms, including abdominal pain, vomiting, and weight loss. In mild symptomatic instances, GD is treated conservatively with antacids, but surgical excision is indicated for refractory gastric diverticula with persistent symptoms or complications. We represent an incidental finding of asymptomatic gastric diverticulum through endoscopy for a 12-year-old Saudi male who presented after foreign body ingestion.

Magnetic Dipole and Thermophoretic Particle Deposition Impact on Bioconvective Oldroyd-B Fluid Flow over a Stretching Surface with Cattaneo-Christov Heat Flux.

This study emphasizes the performance of two-dimensional electrically non-conducting Oldroyd-B fluid flowing across a stretching sheet with thermophoretic particle deposition. The heat and mass transfer mechanisms are elaborated in the presence of a magnetic dipole, which acts as an external magnetic field. The fluid possesses magnetic characteristics due to the presence of ferrite particles. The gyrotactic microorganisms are considered to keep the suspended ferromagnetic particles stable. Cattaneo-Christov heat flux is cogitated instead of the conventional Fourier law. Further, to strengthen the heat transfer and mass transfer processes, thermal stratification and chemical reaction are employed. Appropriate similarity transformations are applied to convert highly nonlinear coupled partial differential equations into non-linear ordinary differential equations (ODEs). To numerically solve these ODEs, an excellent MATLAB bvp4c approach is used. The physical behavior of important parameters and their graphical representations are thoroughly examined. The tables are presented to address the thermophoretic particle velocity deposition, rate of heat flux, and motile microorganisms' density number. The results show that the rate of heat transfer decreases as the value of the thermal relaxation time parameter surges. Furthermore, when the thermophoretic coefficient increases, the velocity of thermophoretic deposition decreases.

Hybrid Nanofluid Flow Induced by an Oscillating Disk Considering Surface Catalyzed Reaction and Nanoparticles Shape Factor.

Lately, a new class of nanofluids, namely hybrid nanofluids, has been introduced that performs much better compared with the nanofluids when a healthier heat transfer rate is the objective of the study. Heading in the same direction, the present investigation accentuates the unsteady hybrid nanofluid flow involving CuO, Al2O3/C2H6O2 achieved by an oscillating disk immersed in the porous media. In a study of the homogeneous and heterogeneous reactions, the surface catalyzed reaction was also considered to minimize the reaction time. The shape factors of the nanoparticles were also taken into account, as these play a vital role in assessing the thermal conductivity and heat transfer rate of the system. The assumed model is presented mathematically in the form of partial differential equations. The system is transformed by invoking special similarity transformations. The Keller Box scheme was used to obtain numerical and graphical results. It is inferred that the blade-shaped nanoparticles have the best thermal conductivity that boosts the heat transfer efficiency. The oscillation and surface-catalyzed chemical reactions have opposite impacts on the concentration profile. This analysis also includes a comparison of the proposed model with a published result in a limiting case to check the authenticity of the presented model.

Significance of induced hybridized metallic and non-metallic nanoparticles in single-phase nano liquid flow between permeable disks by analyzing shape factor.

The current communication is designed by keeping in the mind high heat transfer capabilities of nanoliquids with the dispersion of diversified-natured nanoparticles in poorly conducting base liquids. Here, an amalgamation of metallic (Cu) and hybridization of metallic and non-metallic oxide (Cu-TiO2) nanoparticles to uplift thermophysical attributes of water is deliberated. The magnetically affected flow between rotating disks under the impact and permeability aspect is assumed. Empirical relations for effective dynamic viscosity, density, and heat capacitance to show mesmerizing features of obliged nanoparticles are also expressed. In addition, mathematical relations also depend on morphological factors like shape, size, and diameter of inducted nanoparticles. The mathematical formulation of the problem is conceded in the form of a system of ODEs after using similarity transformation on dimensional PDEs. Simulations of the complex coupled differential structure are solved by using a numerical approach by employing shooting and Runge-Kutta procedures jointly. The impact of flow concerning variables on associated distributions is revealed through tabular and graphical manner. Quantities of engineering interest associated with work like wall friction and thermal flux coefficients at walls of the disk are also calculated. It is deduced from an examination that the addition of metallic particles raises heat transfer more than non-metallic particles. A significant impression of magnetic field on shear stress is executed by hybrid nanoparticles along the surface of disks. In addition, elevation in Nusselt number and depreciation in skin friction coefficient is revealed against increasing magnitude of nanoparticle volume fraction. A positive trend in skin friction coefficient is manifested against the increasing magnitude of Reynold number. It is also observed that by increasing the size and shape of hybrid nanoparticles thermal conductivity and viscosity of the base fluid increases.

Hydrodynamic and heat transfer analysis of dissimilar shaped nanoparticles-based hybrid nanofluids in a rotating frame with convective boundary condition.

Solar thermal systems have low efficiency due to the working fluid's weak thermophysical characteristics. Thermo-physical characteristics of base fluid depend on particle concentration, diameter, and shapes. To assess a nanofluid's thermal performance in a solar collector, it is important to first understand the thermophysical changes that occur when nanoparticles are introduced to the base fluid. The aim of this study is, therefore, to analyze the hydrodynamic and heat characteristics of two different water-based hybrid nanofluids (used as a solar energy absorber) with varied particle shapes in a porous medium. As the heat transfer surface is exposed to the surrounding environment, the convective boundary condition is employed. Additionally, the flow of nanoliquid between two plates (in parallel) is observed influenced by velocity slip, non-uniform heat source-sink, linear thermal radiation. To make two targeted hybrid nanofluids, graphene is added as a cylindrical particle to water to make a nanofluid, and then silver is added as a platelet particle to the graphene/water nanofluid. For the second hybrid nanofluid, CuO spherical shape particles are introduced to the graphene/water nanofluid. The entropy of the system is also assessed. The Tiwari-Das nanofluid model is used. The translated mathematical formulations are then solved numerically. The physical and graphical behavior of significant parameters is studied.

Performance-based comparison of Yamada-Ota and Hamilton-Crosser hybrid nanofluid flow models with magnetic dipole impact past a stretched surface.

The nanofluid flows play a vital role in many engineering processes owing to their notable industrial usage and excessive heat transfer abilities. Lately, an advanced form of nanofluids namely "hybrid nanofluids" has swapped the usual nanofluid flows to further augment the heat transfer capabilities. The objective of this envisaged model is to compare the performance of two renowned hybrid nanofluid models namely Hamilton-Crosser and Yamada-Ota. The hybrid nanoliquid (TiO2-SiC/DO) flow model is comprised of Titanium oxide (TiO2) and Silicon carbide (SiC) nanoparticles submerged into Diathermic oil (DO). The subject flow is considered over a stretched surface and is influenced by the magnetic dipole. The uniqueness of the fluid model is augmented by considering the modified Fourier law instead of the traditional Fourier law and slip conditions at the boundary. By applying the suitable similarity transformations, the system of ordinary differential equations obtained from the leading partial differential equations is handled by the MATLAB solver bvp4c package to determine the numerical solution. It is divulged that the Yamada-Ota model performs considerably better than the Hamilton-Crosser flow model as far as heat transfer capabilities are concerned. Further, the velocity reduces on increasing hydrodynamic interaction and slip parameters. It is also noted that both temperature profiles increase for higher hydrodynamic interaction and viscous dissipation parameters. The envisioned model is authenticated when compared with an already published result in a limiting case.

Significance low oscillating magnetic field and Hall current in the nano-ferrofluid flow past a rotating stretchable disk.

The present investigation involves the Hall current effects past a low oscillating stretchable rotating disk with Joule heating and the viscous dissipation impacts on a Ferro-nanofluid flow. The entropy generation analysis is carried out to study the impact of rotational viscosity by applying a low oscillating magnetic field. The model gives the continuity, momentum, temperature, magnetization, and rotational partial differential equations. These equations are transformed into the ODEs and solved by using bvp4c MATLAB. The graphical representation of arising parameters such as effective magnetization and nanoparticle concentration on thermal profile, velocity profile, and rate of disorder along with Bejan number is presented. Drag force and the heat transfer rate are given in the tabular form. It is comprehended that for increasing nanoparticle volume fraction and magnetization parameter, the radial, and tangential velocity reduce while thermal profile surges. The comparison of present results for radial and axial velocity profiles with the existing literature shows approximately the same results.

Pigmented spherical body floating within the globe.

Vitreous cysts are rare ocular malformations. We report an unusual case of a pigmented free-floating vitreous cyst incidentally detected in a highly myopic 28-year-old woman who was referred by her optometrist.

Expression of two novel transcripts in the mouse definitive endoderm.

Here we describe the expression of two novel transcripts, Ende (AK014119) and Npe (AK084355), during early mouse embryogenesis. Ende mRNA was first detected at embryonic day (E) 7.0 in a small population of epiblast cells in the distal half of the embryo. At E7.5, Ende was expressed by newly formed definitive endoderm cells in the proximal half of the embryo, and was not expressed in extra-embryonic endoderm. This expression pattern then changed to the ventral aspect of the developing foregut pocket and the entire hindgut pocket at E8.0-8.5, before becoming restricted to the foregut overlying the heart and the posterior-most hindgut. By E9.25 Ende expression was also observed in the posterior half of the ventral neural tube. Thus, Ende was expressed dynamically and in specific populations of the definitive endoderm from E7.0 to E8.5. We found Npe expression to be restricted to the node/posterior notochord region at the distal tip of the embryo between E7.0 and E8.0. By E9.5, Npe expression was observed in the posterior-most population of dorsal hindgut cells and notochord cells. Given their expression in mouse definitive endoderm populations, Ende and Npe will be valuable tools to study formation and development of this tissue.

A simultaneous radioimmunoassay for aldosterone and its precursors: human plasma levels following the inhibition of converting enzyme, before and after blockade of prostaglandin biosynthesis.

Plasma aldosterone, 18-hydroxycorticosterone, corticosterone, 18-hydroxydeoxycorticosterone, and deoxycorticosterone were determined in 15 healthy male volunteers (34 +/- 2 years) following the inhibition of converting enzyme with captopril (SQ 14.225), either with or without indomethacin pretreatment. These studies were performed with the aid of a radioimmunological method for the simultaneous determination of the steroids from 1.0 ml of plasma. The procedure involves one extraction and one chromatographic step. Highly sensitive and specific rabbit antisera were raised for all steroids. Precision and accuracy are shown to be equivalent to those of single steroid radioimmunoassays. Without indomethacin pretreatment a constant and significant fall in aldosterone and 18-hydroxycorticosterone plasma levels was obtained after captopril. 18-Hydroxydeoxycorticosterone and corticosterone did not change after inhibition of converting enzyme. Under indomethacin pretreatment all basal steroid levels were significantly reduced. After captopril, aldosterone did not change and 18-hydroxycorticosterone showed a smaller decrease than without indomethacin. 18-Hydroxydeoxycorticosterone and corticosterone increased significantly 1 1/2 hour after captopril. We conclude that indomethacin significantly reduces basal mineralocorticoid production of adrenal zona glomerulosa and fasciculata. Furthermore, the effect of captopril on aldosterone and 18-hydroxycorticosterone is abolished or diminished by inhibition of prostaglandin biosynthesis, but indomethacin does not prevent an augmented secretion of 18-hydroxydeoxycorticosterone and corticosterone.

Paper chromatographic systems for the separation of aldosterone, 18-hydroxycorticosterone, 18-hydroxydeoxycorticosterone, corticosterone and deoxycorticosterone.

Regulation of aldosterone (Aldo) biosynthesis is still open to controversy. The direct sites of action of the known stimulants (e.g., potassium, angiotensin II, adrenocorticotropin) on the different enzymes involved in the biochemical pathway of Aldo are not yet clearly defined. We have developed a radioimmunoassay for the determination of Aldo, 18-hydroxycorticosterone (18OH-B), 18-hydroxydeoxycorticosterone (18OH-DOC), corticosterone (B) and deoxycorticosterone (DOC) in plasma. The aim was to evaluate a single chromatographic system for the separation of these five mineralocorticoids before radioimmunoassay.

Aldosterone 18-glucuronide excretion determined with and without chromatography in human hypertensives.

24 h-urine excretion of aldosterone-18-glucuronide was determined with and without preceding paper chromatography in patients with essential hypertension (n = 50). Radioimmunoassay was performed with a highly specific antibody against aldosterone. Urine specimens determined without chromatography gave significantly higher values than aliquots which were estimated at the same time with chromatography. A highly significant correlation was found between the two methods (r = 0.91, p less than 0.0001). Without chromatography, mean over estimation in samples with concentrations in the low and middle range was on average 32 and 24% respectively, whereas aldosterone concentrations in the upper range showed a 14% over estimation. The RIA procedure for aldosterone without chromatography as here described is suitable for hypertension screening programmes to exclude known forms of primary hyperaldosteronism in which elevated aldosterone excretion rates have to be differentiated from values lying within the normal range.