scholarly journals The Flow in Periciliary Layer in Human Lungs with Navier-Stokes-Brinkman Equations

2021 ◽  
Vol 54 ◽  
Author(s):  
Kanognudge Wuttanachamsri ◽  
Nattapol Oangwatcharaparkan
Keyword(s):  
Immune System ◽  
Numerical Solutions ◽  
Time Derivative ◽  
The Body ◽  
Navier Stokes ◽  
Human Respiratory Tract ◽  
Brinkman Equations ◽  
Numerical Result ◽  
Human Lungs ◽  
Bottom Boundary Condition

In the human respiratory tract, air breathed in is often contaminated with strange particles such as dust and chemical spray, which may cause people respiratory diseases. However, the human body has an innate immune system that helps to trap the debris by secreting mucus to catch the foreign particles, which are removed from the body by the movement of tiny hairs lining on the surface of the epithelial cells in the immune system. The layer containing the tiny hairs or cilia is called Periciliary Layer (PCL). In this research, we find the velocity of the fluid in the PCL moved by a ciliary beating by using the Navier-Stokes-Brinkman equations. We apply the Galerkin finite element method to determine numerical solutions. For the steady linear case of the equation, the numerical result is in good agreement with an exact solution. Including the time derivative and nonlinear terms, we show that the velocity of the liquid is affected by the velocity of the solid, which follows the physical meaning of the fluid flow. The result can be applied as a bottom boundary condition of the mucous layer to be able to find the velocity of mucus in the human lungs.

NUMERICAL SOLUTIONS OF 2D AND 3D SLAMMING PROBLEMS

2021 ◽  
Vol 153 (A2) ◽  
Author(s):  
Q Yang ◽  
W Qiu
Keyword(s):  
Free Surface ◽  
Numerical Solutions ◽  
Stokes Equations ◽  
Type Equation ◽  
The Body ◽  
Navier Stokes ◽  
Time Step ◽  
Navier Stokes Equations ◽  
Highly Nonlinear ◽  
2D And 3D

Slamming forces on 2D and 3D bodies have been computed based on a CIP method. The highly nonlinear water entry problem governed by the Navier-Stokes equations was solved by a CIP based finite difference method on a fixed Cartesian grid. In the computation, a compact upwind scheme was employed for the advection calculations and a pressure-based algorithm was applied to treat the multiple phases. The free surface and the body boundaries were captured using density functions. For the pressure calculation, a Poisson-type equation was solved at each time step by the conjugate gradient iterative method. Validation studies were carried out for 2D wedges with various deadrise angles ranging from 0 to 60 degrees at constant vertical velocity. In the cases of wedges with small deadrise angles, the compressibility of air between the bottom of the wedge and the free surface was modelled. Studies were also extended to 3D bodies, such as a sphere, a cylinder and a catamaran, entering calm water. Computed pressures, free surface elevations and hydrodynamic forces were compared with experimental data and the numerical solutions by other methods.

Three-Dimensional Effects on Slamming Loads

2021 ◽  
Author(s):  
Shan Wang ◽  
C. Guedes Soares
Keyword(s):  
3D Model ◽  
Numerical Solutions ◽  
Pressure Coefficient ◽  
Three Dimensional ◽  
The Body ◽  
Navier Stokes ◽  
Courant Number ◽  
Dimensional Effects ◽  
Coefficient Distribution ◽  
Experimental Values

Abstract Three-dimensional effects on slamming loads predictions of a ship section are investigated numerically using the unsteady incompressible Reynolds-Average Navier-Stokes (RANS) equations and volume of fluid (VOF) method, which are implemented in interDyMFoam solver in open-source library OpenFoam. A convergence and uncertainty study is performed considering different resolutions and constant Courant number (CFL) following the ITTC guidelines. The numerical solutions are validated through comparisons of slamming loads and motions between the CFD simulations and the available experimental values. The total slamming force and slamming pressures on a 2D ship section and the 3D model are compared and discussed. Three-dimensional effects on the sectional force and the pressures are quantified both in transverse and longitudinal directions of the body considering various entry velocities. The non-dimensional pressure coefficient distribution on the 3D model is presented.

Fractional order model of immune cells influenced by cancer cells

2019 ◽  
Vol 14 (3) ◽  
pp. 308 ◽  
Author(s):  
Esmehan Ucar ◽  
Necati Özdemir ◽  
Eren Altun
Keyword(s):  
Mathematical Model ◽  
Immune System ◽  
Cancer Cells ◽  
Numerical Solutions ◽  
Excellent Result ◽  
Interleukin 2 ◽  
The Body ◽  
Living Body ◽  
Fractional Models ◽  
The Mathematical Model

In this paper, we study the mathematical model of interaction cancer cells and immune system cells presented Castiglione and Piccoli. As the interaction between cancer cells and the immune system is weak, when the immune system of the body begins to decrease, the cancer cells get stronger and increase rapidly. Helper CD4+ T and cytotoxic CD8+ T cells, cancer cells, dendritic cells and cytokine interleukin-2 (IL-2) cells are involved in the mathematical model of this competition in the living body. As can be seen in the literature, since the cancer cells have memory structure, fractional models describe the struggle between the cancer cells and immune system give more meaningful results than classical models as closer to the reality. The main motivation of the present work is to generalize the model in Castiglione and Piccoli [J. Theor. Biol. 247 (2007) 723–732] by using Caputo fractional derivative. The main aim is to analyze the behaviors of system cells by changing of the fractional parameter. In this sense, we study on the stability analysis of treatment free and the fixed points of the prescribed model. To get the numerical solutions, we apply the Adam-Bashforth-Moulton (ABM) algorithm and also illustrate the results by the graphics held by Matlab program. We have reached the excellent result that cancer cells decrease as θ diminishes in this process.

All Speed and High-Resolution Scheme Applied to Three-Dimensional Multi-Block Complex Flowfield System

2004 ◽  
Vol 20 (1) ◽  
pp. 13-25 ◽  
Author(s):  
Uzu- Kuei Hsu ◽  
Chang- Hsien Tai ◽  
Chien- Hsiung Tsai
Keyword(s):  
Steady State ◽  
Incompressible Flows ◽  
Numerical Solutions ◽  
Stokes Equations ◽  
Diffusion Flux ◽  
Time Derivative ◽  
Splitting Method ◽  
Three Dimensional ◽  
Navier Stokes ◽  
Complex Flow

ABSTRACTThe improved numerical approach is implemented with preconditioned Navier-Stokes solver on arbitrary three-dimensional (3-D) structured multi-block complex flowfield. With the successful application of time-derivative preconditioning, present hybrid finite volume solver is performed to obtain the steady state solutions in compressible and incompressible flows. This solver which combined the adjective upwind splitting method (AUSM) family of low-diffusion flux-splitting scheme with an optimally smoothing multistage scheme and the time-derivative preconditioning is used to solve both the compressible and incompressible Euler and Navier-Stokes equations. In addition, a smoothing procedure is used to provide a mechanism for controlling the numerical implementation to avoid the instability at stagnation and sonic region. The effects of preconditioning on accuracy and convergence to the steady state of the numerical solutions are presented. There are two validation cases and three complex cases simulated as shown in this study. The numerical results obtained for inviscid and viscous two-dimensional flows over a NACA0012 airfoil at free stream Mach number ranging from 0.1 to 1.0E-7 indicates that efficient computations of flows with very low Mach numbers are now possible, without losing accuracy. And it is effectively to simulate 3-D complex flow phenomenon from compressible flow to incompressible by using the advanced numerical methods.

Immunity boosting diet during Covid 19

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 832-838
Author(s):  
Roshna Sukheoji Bhutada ◽  
Renu Rathi ◽  
Devyani Dasar
Keyword(s):  
Immune System ◽  
Food Studies ◽  
Egg Yolk ◽  
The Body ◽  
Leafy Vegetables ◽  
Green Leafy Vegetables ◽  
Custard Apple ◽  
The Right ◽  
Daily Physical Activities ◽  
Physiological Reactions

WHO declared Covid 19 /SARS -COV-2 as a global pandemic.Till date, there is no medicine for COVID-19. If the Infection arises in the body then the defence mechanism activated against infection. A recent study suggests that temporarily augmenting the body's immune system in the early stages of COVID-19 can help patient to avoid severe symptoms as it is rightly said prevention is better than cure. Ayurveda approaches to develop physiological reactions to facilitate immunity. Planning of diet is most important to boost immunity.As per many researches to provide supplementary food which contains Zinc, Vitamin C,Vitamin D and immunity boosting foodsuch as citrus natural products, custard apple, apple, papaya is among the Fruits. Vegetables include broccoli, onion, garlic and green leafy vegetables. Nuts, ginger, turmeric, pepper, egg yolk, shellfish, mushroom. The need of the hour is a quick boost to immune system to keep it fit, fighting. One should get the right amount of nutrients from the diet, supplementation regimen to boost immune system.In this review, there are few common supplements and super food studies have been included. It might be a torch bearer as sample menu and their alternatives are given for a normal adult. Needy may change contemplated according to age, sex, body mass index and daily physical activities.

Nutritional Recommendation for COVID-19

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 753-757
Author(s):  
Anagha Gulhane ◽  
Shamli Hiware
Keyword(s):  
Immune System ◽  
Global Health ◽  
Infectious Diseases ◽  
Immune Function ◽  
The Body ◽  
Health Issue ◽  
System Quality ◽  
Life Phase ◽  
Global Health Issue ◽  
Nutritional Recommendation

It is the most unreliable truth that anybody can get infected by the COVID-19, and nobody can escape from the danger of getting tainted by the virus. Yet, the line of hope is that anyone and everyone can boost their resistance, thus avoid the risk of getting affected by the illness. The immunity of humans pulls down as they grow older. If their immune system is robust, them falling sick is feeble. If their resistance is weak, them getting ill is sound. Several factors affect the immune system and its ability, including its nourishment. A two-way connection between nutrition, infection and immunity presents. Changes in one part will affect the others part in our body that's the nature's rule. Well defined immune system quality which is present between each life phase may influence the type, generality and the degree of infections. At the same time, low nutrition to the body will decrease the immune function and expose the body to the danger of getting infected by infectious diseases. Different quantity of micronutrients is required for increasing the immunity power of our body. Generally the vitamins A,C,D,E,B2,B6,B12, iron, zinc and selenium.The deficiencies of micronutrients are acknowledged as a global health issue, and also low nutrition makes it prone to establishes the infections in the body.

Role of Rasayana in Prevention of COVID-19 - A Review

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 716-722
Author(s):  
Sneha Dhakite ◽  
Sadhana Misar Wajpeyi
Keyword(s):  
Immune System ◽  
Respiratory System ◽  
Viral Infections ◽  
Cost Effective ◽  
The Body ◽  
Healthy Life ◽  
Vital Functions ◽  
Healthy Life Style ◽  
And Control

The “Coronavirus disease 19 (COVID-19)” is caused by “Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)”, a newly discovered member of the Coronaviridae family of viruses which is a highly communicable. There is no effective medical treatment till date for Coronavirus disease hence prevention is the best way to keep disease away. Rasayana proved to be highly efficacious and cost effective for the Prevention and Control of viral infections when vaccines and standard therapies are lacking. Rasayana Chikitsa is one of the eight branches of Ashtanga Ayurveda which helps to maintain healthy life style. Rasayana improves immunity and performs many vital functions of human body. Vyadhikshamatva that is immune mechanism of the body is involved in Prevention of the occurrence of a new disease and it also decreases the virulence and progression of an existing disease. In COVID-19 the Respiratory system mainly get affected which is evident from its symptoms like cold, cough and breathlessness. Here the drugs help in enhancing immune system and strengthening functions of Respiratory system can be useful. For this purpose, the Rasayana like Chyavanprasha, Agastya Haritaki, Pippali Rasayana, Guduchi, Yashtimadhu, Haridra, Ashwagandha, Tulsi are used. Rasayana working on Respiratory system are best for Prevention of Coronavirus and boosting immune system. Rasayana Chikitsa can be effective in the Prevention as well as reducing symptoms of COVID-19.

Pathway of Inflammation due to Asbestiform fiber "Fluoro-edenite" Exposure: an Update

2020 ◽  
Vol 16 ◽  
Author(s):  
Caterina Ledda ◽  
Claudia Lombardo ◽  
Elisabetta A. Tendi ◽  
Maria Hagnas ◽  
Gianluca Paravizzini ◽  
...  
Keyword(s):  
Immune System ◽  
Autoimmune Disease ◽  
Early Response ◽  
The Body ◽  
Volcanic Area ◽  
Asbestos Fibers ◽  
Inflammatory Processes

: Fluoro-edenite (FE) is an asbestos-like amphibole present in the bentonitic lavas extracted from a stone quarry in Biancavilla, a village sited in the Etnean Volcanic Area (Italy). : Thoracic pathologies are the results of excessive inflammatory processes that are the early response of the immune system to inhaled fibers. As demonstrated for asbestos, fibers may trigger immune system cells in an acute and/or chronic manner. This review aims to clarify the pathways of inflammation in workers exposed to FE fibers. : Based on the articles reviewed, it seems that a permanent stimulus created by repeatedly inhaling the FE fibers and their persistence in the body can act as trigger both in promoting inflammatory processes and in immunological induction of autoimmune disease.

scholarly journals Involvement of Probiotics and Postbiotics in the Immune System Modulation

Biologics ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 89-110
Author(s):  
Neslihan Yeşilyurt ◽  
Birsen Yılmaz ◽  
Duygu Ağagündüz ◽  
Raffaele Capasso
Keyword(s):  
Immune System ◽  
Pharmaceutical Industry ◽  
Intestinal Microbiota ◽  
Health Benefits ◽  
The Body ◽  
Future Research ◽  
Immune Systems ◽  
Advantages And Disadvantages ◽  
Immune System Modulation ◽  
Molecular Patterns

Intestinal microbiota interacts with other systems, especially the immune system, which is responsible for protecting the body by recognizing “stranger” (pathogen associated molecular patterns-PAMPs) and “danger” (damage-associated molecular patterns-DAMPs) molecular motifs. In this manner, it plays an important role in the pathogenesis of various diseases and health. Despite the use of probiotics that modulate the intestinal microbiota in providing health benefits and in the treatment of diseases, there are some possible concerns about the possibility of developing adverse effects, especially in people with suppressed immune systems. Since probiotics provide health benefits with bioactive compounds, studies are carried out on the use of products containing non-living probiotic microorganisms (paraprobiotics) and/or their metabolites (postbiotics) instead of probiotic products. It is even reported that these microbial compounds have more immunomodulatory activities than living microorganisms via some possible mechanism and eliminates some disadvantages of probiotics. Considering the increasing use of functional foods in health and disease, further studies are needed with respect to the benefits and advantages of parabiotic and/or postbiotic use in the food and pharmaceutical industry as well as immune system modulation. Although probiotics have been extensive studied for a long time, it seems that postbiotics are promising tools for future research and applications according to the recent literature. This review aimed to evaluate the interaction of probiotics and postbiotics with the immune systems and also their advantages and disadvantages in the area of food-pharmaceutical industry and immune system modulation.

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