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(R1480) Heat Transfer in Peristaltic Motion of Rabinowitsch Fluid in a Channel with Permeable Wall
Get PDFThis paper is intended to investigate the effect of heat transfer on the peristaltic flow of Rabinowitsch fluid in a channel lined with a porous material. The Navier -Stokes equation governs the channel\u27s flow, and Darcy\u27s law describes the permeable boundary. The Rabinowitsch fluid model\u27s governing equations are solved by utilizing approximations of the long-wavelength and small number of Reynolds. The expressions for axial velocity, temperature distribution, pressure gradient, friction force, stream function are obtained. The influence on velocity, pressure gradient, friction force, and temperature on pumping action of different physical parameters is explored via graphs
(R1523) Abundant Natural Resources, Ethnic Diversity and Inclusive Growth in Sub-Saharan Africa: A Mathematical Approach
Get PDFThe sub-Saharan African region is blessed with abundant natural resources and diverse ethnic groups, yet the region is dominated by the largest number of poor people worldwide due to inequitable distribution of national income. Existing statistics forecast decay in the quality of lives over the years compared to the continent of Asia that shares similar history with the region. In this paper, a-five dimensional first-order nonlinear ordinary differential equations was formulated to give insight into various factors that shaped dynamics of inclusive growth in sub-Saharan Africa. The validity test was performed based on ample mathematical theorems and the model was found to be valid. The model was then studied qualitatively and quantitatively via stability theory of nonlinear differential equations which depended on the policy success ratio and classical fourth-order Runge-Kutta scheme implemented in maple respectively. The results from the analysis showed that inclusive growth from abundant natural resources and ethnic diversity in sub-Saharan Africa was a function of policy reform whereby an increase in both equitable distribution of national income and accessibility of common man to the goods and services provided by the state to narrow inequality gap was accompanied with a low level of nepotism
The Nutrition-COVID-19 Interplay: a Review
No full textPurpose of Review: Nutritional status is affected by the COVID-19 pandemic, directly or indirectly. Even with the recent rollout of the coronavirus disease 2019 (COVID-19) vaccines and availability of medicines such as remdesivir, and monoclonal antibodies, host nutritional status is pivotal in the fight against the acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and outcomes. The purpose of this review is to discuss the effects of COVID-19-related lockdown on lifestyle behaviors, and the nutritional consequences, and the direct sequelae of the infection on nutrition including potential nutritional interventions. Recent Findings: The COVID-19-related lockdown imposed radical changes in lifestyle behaviors with considerable short-term and long-term health and nutritional consequences including weight gain and obesity and increased cardiometabolic risk, consistently linked to worsened prognosis. The extent of the impact was dependent on food insecurity, overall stress and disordered eating, physical inactivity, and exposure to COVID-19-related nutrition information sources. COVID-19 could directly induce inflammatory responses and poor nutrient intake and absorption leading to undernutrition with micronutrient deficiencies, which impairs immune system function with subsequent amplified risk of infection and disease severity. Nutrition interventions through nutrition support, dietary supplementation, and home remedies such as use of zinc, selenium, vitamin D, and omega-3 fatty acids showed the most significant promise to mitigate the course of COVID-19 infection and improve survival rates. Summary: The nutrition-COVID-19 relationship and related dietary changes mimic a vicious cycle of the double burden of malnutrition, both obesity and undernutrition with micronutrient deficiencies, which promote infection, disease progression, and potential death
Differential expression of α6 and β1 integrins reveals epidermal heterogeneity at single-cell resolution
No full textSkin epidermis is a constantly renewing epithelium that is composed of various cell types and provides an ideal model system for tissue regeneration and heterogeneity studies. Integrins are a family of transmembrane receptors that mediate cell adhesion in the epidermis, and integrin expression spatially reflects epidermal heterogeneity. It remains unclear whether differential expression of integrins can characterize cell types in skin epidermis. This study applied a fluorescence-activated cell sorting (FACS) strategy based on differential expression of α6 and β1 integrins, and used transcriptome analysis to explore epidermal heterogeneity. First, epidermal cells were acquired from C57BL/6 mice back skin. Nine bulk-cell populations were sorted with differential expressions of α6 and β1 integrins, and were successfully characterized as the main cell types in the epidermis through RNA-seq and transcriptome analysis. Then, tetOKrt14-H2BGFP mice were used to trace the cell proliferation rate during wound healing with GFP intensity. Epidermal cells were acquired from the re-epithelialized back skin wounds, and a total of 576 single cells were sorted, combining integrin expression and GFP tracing. FACS single-cell RNA-seq enabled high resolution in the classification of subtypes in both interfollicular epidermis and hair follicle, and both quiescent and intermediate cell states of the basal and infundibulum stem cell populations were distinguished. This study proposed a presorted method to investigate the relationship between integrin expression and epidermal heterogeneity. Multiple epidermal cell types and their expression profiles were identified, which provides data resources for dermatology research
Iron(0)-Catalyzed Hydrothermal Liquefaction of Switchgrass: the Effects of Co-Catalysts and Reductive Conditions
No full textThe effects of a series of co-catalysts: iron(III)chloride, zinc chloride, sodium borate, acetic acid, oxalic acid, 10% Pd-C, sodium carbonate, and Raney-Ni as well as H2 at 200 psi reductive conditions were studied on the iron(0)-catalyzed hydrothermal liquefaction of switchgrass at 210 °C. The addition 10% (w/w) iron(III)chloride as a co-catalyst in 60% aq. ethanol, without a hydrogen atmosphere enhanced the liquefaction yield from 55.7 ± 1.5 to 67.6 ± 2.5%. The use of Pd/C (5% w/w) and Raney-Ni (5% w/w) as co-catalysts could also enhance the liquefaction yields to 67.0 ± 3.0 and 72.3 ± 1.8% respectively, in reactions carried out under hydrogen atmosphere at 200 psi, in H2O, 210 °C, 24 h. GC-MS analysis of the liquefaction products revealed that C5-C10 range partially oxygenated products are formed and the composition of the liquefaction product depends on the co-catalyst used. The thermogravimetric and FT-IR analysis of liquefaction residues indicated that polysaccharide fraction is mainly liquefied in these iron(0)-catalyzed liquefactions of switchgrass at 210 °C
Effect of Induced Magnetic Field on Mixed Convection Flow in a Vertical Channel with Symmetric and Asymmetric Wall Heating Conditions
Get PDFThe present paper concerns the study of the induced magnetic field effect on mixed convection flow of viscous incompressible electrically conducting fluid in a vertical channel with symmetric and asymmetric wall heating conditions with heat generation. A steady, laminar, and fully developed flow is considered. Through the appropriate choice of dimensionless variable, the governing equations are developed and three types of thermal boundary conditions isothermal-isothermal, isoflux-isothermal, and isothermal-isoflux for the left-right wall of the channel have prescribed. The analytical solutions for the velocity field, temperature field, magnetic field, and induced current density have been acquired for three types of thermal boundary conditions. A parametric study has been conducted and, the graphical results are exhibited for the velocity field, magnetic field, induced current density, and Nusselt number
Fuzzy Solutions to Second Order Three Point Boundary Value Problem
Get PDFIn this manuscript, the proposed work is to study the existence of second-order differential equations with three point boundary conditions. Existence is proved using fuzzy set valued mappings of a real variable whose values are normal, convex, upper semi continuous and compactly supported fuzzy sets. The sufficient conditions are also provided to establish the existence results of fuzzy solutions of second order differential equations for three point boundary value problem. By using Banach fixed point principle, a new existence theorem of solutions for these equations in the metric space of normal fuzzy convex sets with distance given by the maximum of the Hausdorff distance between level sets is obtained. Then to further establish the existence, fixed point theorem for absolute retracts is used by taking consideration that space of fuzzy sets can be embedded isometrically as a cone in Banach space. Finally, an example is provided to illustrate the result
Approximate Solutions for the Nonlinear Systems of Algebraic Equations Using the Power Series Method
Get PDFIn this paper, the approximate solutions for systems of nonlinear algebraic equations by the power series method (PSM) are presented. Illustrative examples have been presented to demonstrate the efficiency of the proposed method. In addition, the obtained results are compared with those obtained from the standard Adomian decomposition method. It turns out that the convergence of the proposed algorithm is rapid
On an Ecological Model of Mutualisim Between Two Species With a Mortal Predator
Get PDFIn this paper, we study an ecological model of a three-space food chain consists of two logically growing mutual species and third species acts as a predator to second mutual species with Holling type II functional response. This model is constituted by a system of nonlinear decoupled ordinary differential equations. By using perturbed method, we identify the nature of the system at each equilibrium point and also global stability is investigated for this model using Lypanov function at the possible equilibrium points
Generation of HeLa spheroids in Ca-alginate-PEG microbeads using flicking technique as an improved three-dimensional cell culture system
No full textIn a conventional three-dimensional (3D) cell culture system based on microencapsulation, the calcium alginate microcapsules tend to rupture within 7 days of culture, causing unwanted cell leakage. The microencapsulation based on flicking model of calcium-alginate-polyethylene glycol (Ca-alg-PEG) was proposed to rectify this problem. An analytical model to simulate the flicking process based on the deflection of a needle cantilever was also successfully developed and used to predict the size of the microbeads. The size of the microbeads were ranged from 300 to 500 μm and it is controlled by varying the liquid flow rate from 4.8 to 366 μL/min and flicking speed from 70 to 120 rpm. Under a flicking force of 0.58 N, uniform sized and spherical shaped Ca-alginate-PEG microbeads were produced at a liquid flow rate of 40 μL/min and a flicking rate of 100 rpm. The microbeads were characterized by Field Emission Scanning Microscopy, Atomic Force Microscopy, Raman Spectroscopy and Nanoindentation, and the results indicated improved bio-physical properties of the ca-alginate microbeads after added with PEG. The cell viability test demonstrated that Ca-alginate-PEG microbeads were able to support the growth of viable HeLa cells into spheroids. Resilient calcium-alginate-polyethylene glycol (Ca-alg-PEG) microbeads were found to be able to last up to 15 days before rupturing and greatly reduced the cell leakage problem