Computation of stagnation coating flow of electro-conductive ternary Williamson hybrid [Formula: see text] nanofluid with a Cattaneo-Christov heat flux model and magnetic induction.

Modern smart coating systems are increasingly exploiting functional materials which combine multiple features including rheology, electromagnetic properties and nanotechnological capabilities and provide a range of advantages in diverse operations including medical, energy and transport designs (aerospace, marine, automotive). The simulation of the industrial synthesis of these multi-faceted coatings (including stagnation flow deposition processes) requires advanced mathematical models which can address multiple effects simultaneously. Inspired by these requests, this study investigates the interconnected magnetohydrodynamic non-Newtonian movement and thermal transfer in the Hiemenz plane's stagnation flow. Additionally, it explores the application of a transverse static magnetic field to a ternary hybrid nanofluid coating through theoretical and numerical analysis. The base fluid (polymeric) considered is engine-oil (EO) doped with graphene [Formula: see text], gold [Formula: see text] and Cobalt oxide [Formula: see text] nanoparticles. The model includes the integration of non-linear radiation, heat source, convective wall heating, and magnetic induction effects. For non-Newtonian characteristics, the Williamson model is utilized, while the Rosseland diffusion flux model is used for radiative transfer. Additionally, a non-Fourier Cattaneo-Christov heat flux model is utilized to include thermal relaxation effects. The governing partial differential conservation equations for mass, momentum, energy and magnetic induction are rendered into a system of coupled self-similar and non-linear ordinary differential equations (ODEs) with boundary restrictions using appropriate scaling transformations. The dimensionless boundary value problem that arises is solved using the bvp4c built-in function in MATLAB software, which employs the fourth-order Runge-Kutta (RK-4) method. An extensive examination is conducted to evaluate the impact of essential control parameters on the velocity [Formula: see text], induced magnetic field stream function gradient [Formula: see text] and temperature [Formula: see text] is conducted. The relative performance of ternary, hybrid binary and unitary nanofluids for all transport characteristics is evaluated. The inclusion of verification of the MATLAB solutions with prior studies is incorporated. Fluid velocity is observed to be minimized for the ternary [Formula: see text]-[Formula: see text]-[Formula: see text] nanofluid whereas the velocity is maximized for the unitary cobalt oxide [Formula: see text] nanofluid with increasing magnetic parameter ([Formula: see text] Temperatures are elevated with increment in thermal radiation parameter (Rd). Streamlines are strongly modified in local regions with greater viscoelasticity i.e. higher Weissenberg number [Formula: see text]. Dimensionless skin friction is significantly greater for the ternary hybrid [Formula: see text]-[Formula: see text]-[Formula: see text] nanofluid compared with binary hybrid or unitary nanofluid cases.

Progression of blood-borne viruses through bloodstream: A comparative mathematical study.

BACKGROUND AND OBJECTIVES: Blood-borne pathogens are contagious microorganisms that can cause life-threatening illnesses, and are found in human blood. It is crucial to examine how these viruses spread through blood flow in the blood vessel. Keeping that in view, this study aims to determine how blood viscosity, and diameter of the viruses can affect the virus transmission through the blood flow in the blood vessel. A comparative study of bloodborne viruses (BBVs) such as HIV, Hepatitis B, and C, has been addressed in the present model. A couple stress fluid model is used to represent blood as a carrying medium for virus transmission. The Basset-Boussinesq-Oseen equation is taken into account for the simulation of virus transmission. METHODS: An analytical approach to derive the exact solutions under the assumption of long wavelength and low Reynolds number approximations is employed. For the computation of the results, a segment (wavelength) of blood vessels about 120 mm with wave velocities in the range of 49 - 190 mm/sec are considered, where the diameter of BBVs ranges from 40-120 nm. The viscosity of the blood varies from 3.5-5.5 × 10-3Ns/m2 which affect the virion motion having a density range 1.03 - 1. 25 g/m3. RESULTS: It shows that the Hepatitis B virus is more harmful than other blood-borne viruses considered in the analysis. Patients with high blood pressure are highly susceptible for transmission of BBVs. CONCLUSIONS: The present fluid dynamics approach for virus spread through blood flow can be helpful in understanding the dynamics of virus propagation inside the human circulatory system.

Scoping review on the role and interactions of hydroxytyrosol and alpha-cyclodextrin in lipid-raft-mediated endocytosis of SARS-CoV-2 and bioinformatic molecular docking studies.

OBJECTIVE: The aim of the study was to show the effect that two naturally occurring compounds, a cyclodextrin and hydroxytyrosol, can have on the entry of SARS-CoV-2 into human cells. MATERIALS AND METHODS: The PubMed database was searched to retrieve studies published from 2000 to 2020, satisfying the inclusion criteria. The search keywords were: SARS-CoV, SARS-CoV-2, coronavirus, lipid raft, endocytosis, hydroxytyrosol, cyclodextrin. Modeling of alpha-cyclodextrin and hydroxytyrosol were done using UCSF Chimera 1.14. RESULTS: The search results indicated that cyclodextrins can reduce the efficiency of viral endocytosis and that hydroxytyrosol has antiviral properties. Bioinformatic docking studies showed that alpha-cyclodextrin and hydroxytyrosol, alone or in combination, interact with the viral spike protein and its host cell receptor ACE2, thereby potentially influencing the endocytosis process. CONCLUSIONS: Hydroxytyrosol and alpha-cyclodextrin can be useful against the spread of SARS-CoV-2.

Nitric oxide (NO) and salicylic acid (SA): A framework for their relationship in plant development under abiotic stress.

The free radical nitric oxide (NO) and the phenolic phytohormone salicylic acid (SA) are signal molecules which exert key functions at biochemical and physiological levels. Abiotic stresses, especially in early plant development, impose the biggest threats to agricultural systems and crop yield. These stresses impair plant growth and subsequently cause a reduction in root development, affecting nutrient uptake and crop productivity. The molecules NO and SA have been identified as robust tools for efficiently mitigating the negative effects of abiotic stress in plants. SA is engaged in an array of tasks under adverse environmental situations. The function of NO depends on its cellular concentration; at a low level, it acts as a signal molecule, while at a high level, it triggers nitro-oxidative stress. The crosstalk between NO and SA involving different signalling molecules and regulatory factors modulate plant function during stressful situations. Crosstalk between these two signalling molecules induces plant tolerance to abiotic stress and needs further investigation. This review aims to highlight signalling aspects of NO and SA in higher plants and critically discusses the roles of these two molecules in alleviating abiotic stress.

Electrothermal transport of third-order fluids regulated by peristaltic pumping.

The study of heat and electroosmotic characteristics in the flow of a third-order fluid regulated by peristaltic pumping is examined by using governing equations, i.e., the continuity equation, momentum equation, energy equation, and concentration equation. The wavelength is considered long compared to its height and a low Reynolds number is assumed. The velocity slip condition is employed. Analytical solutions are performed through the perturbation technique. The expressions for the dimensionless velocity components, temperature, concentration, and heat transfer rate are obtained. Pumping features were computed numerically for discussion of results. Trapping and heat transfer coefficient distributions were also studied graphically. The findings of the present study can be applied to design biomicrofluidic devices like tumor-on-a-chip and organ-on-a-chip.

Erythrocytes from patients with myeloproliferative neoplasms and splanchnic venous thrombosis show greater expression of Lu/BCAM.

INTRODUCTION: Lutheran/BCAM protein (Lu) on the surface of erythrocytes is key for their adhesion to the endothelium, and erythrocytes from individuals with JAK2V617F-mutated myeloproliferative neoplasms (MPN) have increased endothelial adhesion. Splanchnic vein thrombosis (SVT) is a devastating thrombotic complication of MPN, and frequently, the only diagnostic feature is the JAK2V617F mutation. We sought to examine whether erythrocytes from patients with JAK2V617F mutated SVT (MPN-SVT) exhibited increased Lu expression, thereby supporting a mechanistic contribution to the development of thrombosis. METHODS: We report the validation of a novel flow cytometry assay for Lu expression on erythrocytes. We examined the expression of Lu on erythrocytes from a cohort of MPN patients with and without SVT, and healthy controls. Samples were obtained from 20 normal individuals, 22 with MPN (both JAK2V617F-mutated and wild-type) and 8 with JAK2V617F-mutated MPN-SVT. RESULTS: Lu expression by erythrocytes from patients with MPN and MPN-SVT is significantly increased compared to erythrocytes from healthy individuals (P < .05), but there was no significant difference between patients with MPN-SVT and MPN. CONCLUSIONS: Patients with MPN have increased expression of the red cell Lu/BCAM adhesion molecule. Further work is required to determine the role of the increased Lu/BCAM adhesion to the endothelium in the development of thrombosis in MPN of all genotypes.

Mathematical modelling of pressure-driven micropolar biological flow due to metachronal wave propulsion of beating cilia.

In this paper, we present an analytical study of pressure-driven flow of micropolar non-Newtonian physiological fluids through a channel comprising two parallel oscillating walls. The cilia are arranged at equal intervals and protrude normally from both walls of the infinitely long channel. A metachronal wave is generated due to natural beating of cilia and the direction of wave propagation is parallel to the direction of fluid flow. Appropriate expressions are presented for deformation via longitudinal and transverse velocity components induced by the ciliary beating phenomenon with cilia assumed to follow elliptic trajectories. The conservation equations for mass, longitudinal and transverse (linear) momentum and angular momentum are reduced in accordance with the long wavelength and creeping Stokesian flow approximations and then normalized with appropriate transformations. The resulting non-linear moving boundary value problem is solved analytically for constant micro-inertia density, subject to physically realistic boundary conditions. Closed-form expressions are derived for axial velocity, angular velocity, volumetric flow rate and pressure rise. The transport phenomena are shown to be dictated by several non-Newtonian parameters, including micropolar material parameter and Eringen coupling parameter, and also several geometric parameters, viz eccentricity parameter, wave number and cilia length. The influence of these parameters on streamline profiles (with a view to addressing trapping features via bolus formation and evolution), pressure gradient and other characteristics are evaluated graphically. Both axial and angular velocities are observed to be substantially modified with both micropolar rheological parameters and furthermore are significantly altered with increasing volumetric flow rate. Free pumping is also examined. An inverse relationship between pressure rise and flow rate is computed which is similar to that observed in Newtonian fluids. The study is relevant to hemodynamics in narrow capillaries and also bio-inspired micro-fluidic devices.

Numerical simulation of heat transfer in blood flow altered by electroosmosis through tapered micro-vessels.

A numerical simulation is presented to study the heat and flow characteristics of blood flow altered by electroosmosis through the tapered micro-vessels. Blood is assumed as non-Newtonian (micropolar) nanofluids. The flow regime is considered as asymmetric diverging (tapered) microchannel for more realistic micro-vessels which is produced by choosing the peristaltic wave train on the walls to have different amplitudes and phase. The Rosseland approximation is employed to model the radiation heat transfer and temperatures of the walls are presumed constants. The mathematical formulation of the present problem is simplified under the long-wavelength, low-Reynolds number and Debye-Hückel linearization approximations. The influence of various dominant physical parameters are discussed for axial velocity, microrotation distribution, thermal temperature distribution and nanoparticle volume fraction field. However, our foremost emphasis is to determine the effects of thermal radiation and coupling number on the axial velocity and microrotation distribution beneath electroosmotic environment. This analysis places a significant observation on the thermal radiation and coupling number which plays an influential role in hearten fluid velocity. This study is encouraged by exploring the nanofluid-dynamics in peristaltic transport as symbolized by heat transport in biological flows and also in novel pharmacodynamics pumps and gastro-intestinal motility enhancement.

Joule heating and zeta potential effects on peristaltic blood flow through porous micro vessels altered by electrohydrodynamic.

In most of the medical therapies, electromagnetic field plays important role to modulate the blood flow and to reduce the pain of human body. With this fact, this paper presents a mathematical model to study the peristaltic blood flow through porous microvessels in the presence of electrohydrodynamics. The effects of Joule heating and different zeta potential are also considered. Darcy law is employed for porous medium. The mathematical analysis is carried out in the form of electroosmosis, flow analysis and heat transfer analysis. Velocity slip conditions are imposed to solve momentum equation and thermal energy equation. Time dependent volumetric flow rate is considered which varies exponentially. Closed form solutions for potential function is obtained under Debye-Hückel approximation and velocity and temperature fields are obtained under low Reynolds number and large wavelength approximations. The influence of Hartmann number, electroosmotic parameter, slip parameters, Zeta potential, and couple stress parameter on flow characteristics, pumping characteristics and trapping phenomenon is computed. The effects of thermal slip parameters, Joule heating parameter, and Brinkman number on heat transfer characteristics are also presented graphically. Finally, the effect of Brinkman number on a graph between Nusselt number and Joule heating parameter is examined.

Management of acute upper gastrointestinal bleeding: an update for the general physician.

Acute upper gastrointestinal bleed (AUGIB) is one of the most common medical emergencies in the UK, with roughly one presentation every 6 min. Despite advances in therapeutics and endoscopy provision, mortality following AUGIB over the last two decades has remained high, with over 9,000 deaths annually in the UK; consequently, several national bodies have published UK-relevant guidelines. Despite this, the 2015 UK National Confidential Enquiry into Patient Outcome and Death in AUGIB highlighted variations in practice, raised concerns regarding suboptimal patient care and released a series of recommendations. This review paper incorporates the latest available evidence and UK-relevant guidelines to summarise the optimal pre-endoscopic, endoscopic, and post-endoscopic approach to and management of non-variceal and variceal AUGIB that will be of practical value to both general physicians and gastroenterologists.

IL-21-dependent expansion of memory-like NK cells enhances protective immune responses against Mycobacterium tuberculosis.

Natural killer (NK) cells are traditionally considered as innate cells, but recent studies suggest that NK cells can distinguish antigens, and that memory NK cells expand and protect against viral pathogens. Limited information is available about the mechanisms involved in memory-like NK cell expansion, and their role in bacterial infections and vaccine-induced protective immune responses. In the current study, using a mouse model of tuberculosis (TB) infection, we found that interferon-gamma producing CD3-NKp46+CD27+KLRG1+ memory-like NK cells develop during Bacille Calmette-Guérin vaccination, expand, and provide protection against challenge with Mycobacterium tuberculosis (M. tb). Using antibodies, short interfering RNA and gene-deleted mice, we found that expansion of memory-like NK cells depends on interleukin 21 (IL-21). NKp46+CD27+KLRG1+ NK cells expanded in healthy individuals with latent TB infection in an IL-21-dependent manner. Our study provides first evidence that memory-like NK cells survive long term, expansion depends on IL-21, and involved in vaccine-induced protective immunity against a bacterial pathogen.

Early House Dust Mite Sensitivity in Mumbai Children.

OBJECTIVE: To identify house dust mite (HDM) sensitivity by skin prick test in children with allergic rhinitis, allergic wheezing and eczema. METHODS: In this prospective study, children with persistent or recurrent allergic symptoms of rhinitis, wheezing and eczema were enrolled to undergo skin prick testing. Sensitivity was checked for three mites: Dermatophagoide farinae, Dermatophagoide pteronyssinus, and Blomia tropicalis. RESULTS: Total 92 children underwent skin prick test; 49 (53.2 %) showed significant positivity to one or more dust mite. In the HDM sensitized group, a positive family history of allergic disorders was present in 32 children (65.3 %). In the HDM sensitized group, 18 (36.7 %) children had allergic rhinitis. The youngest child in this group was 12-mo-old. Ten (55.55 %) children were less than 24 mo of age. Significant sensitization to mites was detected in 7 (14.28 %) children with eczema. All children were below 24 mo of age. In children with a tendency to wheeze frequently without any evidence of infections or other systemic disease, 24 (48.9 %) had sensitization to HDM. The youngest child was 15 mo of age. Ten (41.6 %) children were below 24 mo of age. Sensitivity to Blomia tropicalis was detected in 6 (12.24 %) children. Significantly more number of children were sensitive to D. pteronyssinus as compared to D. farinae (65.31 % vs. 46.94 %; p = 0.034). CONCLUSIONS: Children in Mumbai show early sensitization to HDM. D. pteronyssinus is the commonest offending allergen in the index study.

Synthesis, Characterization and Screening for Analgesic and Anti-inflammatory activities of 2, 5-disubstituted 1, 3, 4-oxadiazole derivatives.

The aim of the present investigation was to synthesize, characterize and evaluate analgesic and anti- inflammatory activities of 2, 5-disubstituted 1, 3, 4-oxadiazole derivatives. The reaction of starting material 4-chloro-m-cresol with ethyl chloroacetate in dry acetone affords ethyl (4-chloro-3-methylphenoxy) acetate, which after reacting with the hydrazine hydrate in ethanol yields 2(4-chloro-3-methylphenoxy) acetohydrazide. When 2(4-chloro-3-methylphenoxy) acetohydrazide was treated with different aromatic aldehydes, aromatic acids and carbon disulfide in alcoholic solution, different 3-acetyl-5-[(4-chloro-3-methylphenoxy) methyl]-2-aryl-2, 3-dihydro-1, 3, 4-oxadiazole and 2-[(4-chloro-3-methylphenoxy) methyl]-5-aryl-1, 3, 4-oxadiazole derivatives were obtained. Purity of the derivatives was confirmed by thin layer chromatography and melting point. Structure of these derivatives was set up by determining infrared spectroscopy, nuclear magnetic resonance spectroscopy and mass spectroscopy. Further, the synthesized derivatives were evaluated for their analgesic and anti-inflammatory activities in rodents. In animal studies, the derivatives 3-acetyl-5-[(4-chloro-3- methylphenoxy)methyl]-2-(4-methoxyphenyl)-2,3-dihydro-1, 3, 4-oxadiazole and 4-{5-[(4-chloro-3- methylphenoxy)methyl]-1, 3, 4-oxadiazol-2-yl}pyridine show more potent analgesic activity and the derivatives 2-{3-acetyl-5-[(4-chloro-3-methylphenoxy)methyl]-2,3-dihydro-1, 3, 4-oxadiazol-2-yl}phenol and 3-acetyl-5- [(4-chloro-3-methylphenoxy)methyl]-2-(4-methoxyphenyl)-2,3-dihydro-1, 3, 4-oxadiazole exhibit more potent anti-inflammatory effect as compared to other derivatives. The results of the current study indicate that cyclization of acetohydrazide produces novel oxadiazole derivatives with potent analgesic and anti-inflammatory activities.

Peristaltic Creeping Flow of Power Law Physiological Fluids through a Nonuniform Channel with Slip Effect.

A mathematical study on creeping flow of non-Newtonian fluids (power law model) through a nonuniform peristaltic channel, in which amplitude is varying across axial displacement, is presented, with slip effects included. The governing equations are simplified by employing the long wavelength and low Reynolds number approximations. The expressions for axial velocity, stream function, pressure gradient, and pressure difference are obtained. Computational and numerical results for velocity profile, pressure gradient, and trapping under the effects of slip parameter, fluid behavior index, angle between the walls, and wave number are discussed with the help of Mathematica graphs. The present model is applicable to study the behavior of intestinal flow (chyme movement from small intestine to large intestine). It is also relevant to simulations of biomimetic pumps conveying hazardous materials, polymers, and so forth.

Autophagy mediates HIF2α degradation and suppresses renal tumorigenesis.

Autophagy is a conserved process involved in lysosomal degradation of protein aggregates and damaged organelles. The role of autophagy in cancer is a topic of intense debate, and the underlying mechanism is still not clear. The hypoxia-inducible factor 2α (HIF2α), an oncogenic transcription factor implicated in renal tumorigenesis, is known to be degraded by the ubiquitin-proteasome system (UPS). Here, we report that HIF2α is in part constitutively degraded by autophagy. HIF2α interacts with autophagy-lysosome system components. Inhibition of autophagy increases HIF2α, whereas induction of autophagy decreases HIF2α. The E3 ligase von Hippel-Lindau and autophagy receptor protein p62 are required for autophagic degradation of HIF2α. There is a compensatory interaction between the UPS and autophagy in HIF2α degradation. Autophagy inactivation redirects HIF2α to proteasomal degradation, whereas proteasome inhibition induces autophagy and increases the HIF2α-p62 interaction. Importantly, clear-cell renal cell carcinoma (ccRCC) is frequently associated with monoallelic loss and/or mutation of autophagy-related gene ATG7, and the low expression level of autophagy genes correlates with ccRCC progression. The protein levels of ATG7 and beclin 1 are also reduced in ccRCC tumors. This study indicates that autophagy has an anticancer role in ccRCC tumorigenesis, and suggests that constitutive autophagic degradation of HIF2α is a novel tumor suppression mechanism.

Mathematica numerical simulation of peristaltic biophysical transport of a fractional viscoelastic fluid through an inclined cylindrical tube.

This paper studies the peristaltic transport of a viscoelastic fluid (with the fractional second-grade model) through an inclined cylindrical tube. The wall of the tube is modelled as a sinusoidal wave. The flow analysis is presented under the assumptions of long wave length and low Reynolds number. Caputo's definition of fractional derivative is used to formulate the fractional differentiation. Analytical solutions are developed for the normalized momentum equations. Expressions are also derived for the pressure, frictional force, and the relationship between the flow rate and pressure gradient. Mathematica numerical computations are then performed. The results are plotted and analysed for different values of fractional parameter, material constant, inclination angle, Reynolds number, Froude number and peristaltic wave amplitude. It is found that fractional parameter and Froude number resist the flow pattern while material constant, Reynolds number, inclination of angle and amplitude aid the peristaltic flow. Furthermore, frictional force and pressure demonstrate the opposite behaviour under the influence of the relevant parameters emerging in the equations of motion. The study has applications in uretral biophysics, and also potential use in peristaltic pumping of petroleum viscoelastic bio-surfactants in chemical engineering and astronautical applications involving conveyance of non-Newtonian fluids (e.g. lubricants) against gravity and in conduits with deformable walls.