Analysis of potential flow around two-dimensional body by finite element method

The paper presents a numerical method for analyzing the potential flow around two dimensional body such as single circular cylinder, NACA0012 hydrofoil and double circular cylinders by finite element method. The numerical technique is based upon a general formulation for the Laplace’s equation using Galerkin technique finite element approach. The solution of the systems of algebraic equations is approached by Gaussian elimination scheme. Laplace’s equation is expressed in terms of both steam function and velocity potential formulation. A finite element program is developed in order to analyze the result. The contours of stream and velocity potential function are drawn. The contour of stream function exhibits the characteristics of potential flow and does not intersect each other. The calculated pressure co-efficient shows the pressure decreasing around the forwarded face from the initial total pressure at the stagnation point and reaching a minimum pressure at the top of the cylinder

Evaluation of SLAM algorithms for Search and Rescue applications

This research investigates three SLAM algorithms on a low-cost mobile robot and finds the algorithms’ performance through a set of experiments including different types of ground surfaces

Angelica archengelica extract induced perturbation of rat skin and tight junctional protein (ZO-1) of HaCaT cells

"n  Background and purpose of the study: Herbal enhancers compared to the synthetic ones have shown less toxis effects. Coumarins have been shown at concentrations inhibiting phospoliphase C-Y (Phc-Y) are able to enhance tight junction (TJ) permeability due to hyperpoalation of Zonolous Occludense-1 (ZO-1) proteins. The purpose of this study was to evaluate the influence of ethanolic extract of Angelica archengelica (AA-E) which contain coumarin on permeation of repaglinide across rat epidermis and on the tight junction plaque protein ZO-1 in HaCaT cells. "n Methods: Transepidermal water loss (TEWL) from the rat skin treated with different concentrations of AA-E was assessed by Tewameter. Scanning and Transmission Electron Microscopy (TEM) on were performed on AA-E treated rat skin portions. The possibility of AA-E influence on the architecture of tight junctions by adverse effect on the cytoplasmic ZO-1 in HaCaT cells was investigated. Finally, the systemic delivery of repaglinide from the optimized transdermal formulation was investigated in rats. "n Results: The permeation of repaglinide across excised rat epidermis was 7-fold higher in the presence of AA-E (5% w/v) as compared to propylene glycol:ethanol (7:3) mixture. The extract was found to perturb the lipid microconstituents in both excised and viable rat skin, although, the effect was less intense in the later. The enhanced permeation of repaglinide across rat epidermis excised after treatment with AA-E (5% w/v) for different periods was in concordance with the high TEWL values of similarly treated viable rat skin. Further, the observed increase in intercellular space, disordering of lipid structure and corneocyte detachment indicated considerable effect on the ultrastructure of rat epidermis. Treatment of HaCaT cell line with AA-E (0.16% w/v) for 6 hrs influenced ZO-1 as evidenced by reduced immunofluorescence of anti-TJP1 (ZO-1) antibody in Confocal Laser Scanning Microscopy studies (CLSM) studies. The plasma concentration of repaglinide from transdermal formulation was maintained higher and for longer time as compared to oral administration of repaglinide. "n Major conclusion: Results suggest the overwhelming influence of Angelica archengelica in enhancing the percutaneous permeation of repaglinide to be mediated through perturbation of skin lipids and tight junction protein (ZO-1)

Developing an ESP-Based Language Learning Environment to Help Students Improve Critical Thinking Skills in Written Output

In recent years, as a result of both research discoveries in the fields of foreign language acquisition and learning, the concept of teaching and learning has undergone a significant transformation. English for Specific Purposes (ESP) is a learner-centered approach to teaching English as a foreign language that emphasizes developing communicative proficiency in niche industries such agronomy, commerce, academia, accountancy, education, engineering, and information technology. This concept of English-for-Teaching as a restricted form of ESP for the classroom builds on the knowledge that instructors already have about teaching while also introducing and validating specific classroom terminology. When students interact and cooperate with one another, ESP practice emerges naturally in a language learning setting. Two major aspects that ESP highlights are the growth of dialogical interaction and the establishment of ecologically complete learning environments. In this essay, we create an ESP to aid students in the development of their critical thinking (CT) abilities in written output. We combine the Synergy model, Brain-based learning, and the Flipped Classroom models to create an ESP environment. Students CT abilities and academic success served as the studys criteria. The Course Satisfaction Questionnaire and placement exams were used to obtain the statistical data. Using the Cronbach Alpha coefficient (CAC) and Spearman correlation coefficient, the test on CT data was interpreted, and the combined data was examined using SPSS (V 26.0). By immersing students in problem-solving- based learning (PBL), this paradigm helps students develop their CT skills. It also helps students achieve academically by elevating their sense of accountability for learning outcomes and promoting the use of a variety of learning strategies

Integer Programming Formulations and Cutting Plane Algorithms for the Maximum Selective Tree Problem

This paper considers the Maximum Selective Tree Problem (MSelTP) as a generalization of the Maximum Induced Tree problem. Given an undirected graph with a partition of its vertex set into clusters, MSelTP aims to choose the maximum number of vertices such that at most one vertex per cluster is selected and the graph induced by the selected vertices is a tree. To the best of our knowledge, MSelTP has not been studied before although several related optimization problems have been investigated in the literature. We propose two mixed integer programming formulations for MSelTP; one based on connectivity constraints, the other based on cycle elimination constraints. In addition, we develop two exact cutting plane procedures to solve the problem to optimality. On graphs with up to 25 clusters, up to 250 vertices, and varying densities, we conduct computational experiments to compare the results of two solution procedures with solving a compact integer programming formulation of MSelTP. Our experiments indicate that the algorithm CPAXnY outperforms the other procedures overall except for graphs with low density and large cluster size, and that the algorithm CPAX yields better results in terms of the average time of instances optimally solved and the overall average time

Reinvestigation into the mechanisms of Campylobacter jejuni invasion of intestinal epithelial cells

Background: Campylobacter jejuni is an important foodborne pathogen and the leading cause of bacterial gastroenteritis. Despite the importance of C. jejuni infection and decades of research, the mechanisms for colonisation of the human intestinal tract by C. jejuni and how this causes diarrhoeal disease remain unclear, with a significant number of conflicting reports in the literature creating controversy in this area. Methods: The effect of different inhibitors of host cell pathways on the ability of the C. jejuni 81-176 wild-type strain to interact with and invade intestinal epithelial cells (IECs) was investigated. Defined isogenic C. jejuni 81-176 & 11168H ciaB, cadF and flpA mutants were constructed and characterised for the ability to interact with and invade host cells. Results: Disruption of microfilaments with Cytochalasin D increased C. jejuni invasion. Disruption of caveolae-mediated endocytosis with Methyl-beta-cyclodextrin, disruption of microtubules with Colchicine, disruption of clathrin-mediated endocytosis with Monodansylcadaverine, inhibition of phosphatidylinositol 3-kinase with Wortmannin all decreased C. jejuni invasion. Infection of the Galleria mellonella insect model with ciaB, cadF and flpA mutants resulted in a significantly reduced cytotoxic effect on the larvae. The ability of ciaB, cadF and flpA mutants to interact with and invade Caco-2 and T84 IECs was significantly reduced. The ciaB, cadF and flpA mutants exhibited a more significant decrease in the number of invasive bacteria when co-cultured with IECs in the Vertical Diffusion Chamber model. Pre-treatment of Caco-2 IECs with OMVs isolated from the ciaB, cadF and flpA mutants reduced interactions and invasion of these IECs by live C. jejuni. Conclusion: C. jejuni invasion of IECs involves modulation of many host cell pathways. CiaB, CadF and FlpA all play an important role in C. jejuni interactions with IECs leading to bacterial invasion. Further studies are still required to elucidate the exact roles that these important C. jejuni virulence factors play during interactions with and invasion of host cells

Modeling choices for ecological solid waste management in suburban municipalities : user fees in Tuba, Philippines

Using a participatory approach, this study looks at how a local government in the Philippines might organize and finance solid waste management to meet strict new national targets. Using a "choice modeling" approach, the researchers were able to see how people and companies value the attributes of various waste management services and how much they would be willing to pay for them. The attributes included frequency of waste collection and the methods used to take away the garbage. Based on survey results and an analysis of waste management costs, the study recommends the option with the lowest maintenance and operating costs and the highest cost recovery levels: once-a-week collection of residual waste by municipal workers with a garbage truck. Even with this option, however, user fees could only partially finance the costs of this service. Achieving the new national standards at even a minimum level would leave a suburban municipality with a "funding gap" of PhP 2 million per year between the costs and expected revenue from user fees

Genotoxic damage in cultured human peripheral blood lymphocytes of oral contraceptive users

Synthetic progestins and estrogens have been reported to be toxic in various experimental models. Their prolonged use has been reported to induce cancer in humans. In the present study the effects of oral contraceptives were studied among users using chromosomal aberrations, sister chromatid exchanges and DNA damage as a parameter, in cultured human peripheral blood lymphocytes. The study was performed on 25 women (users) and 25 age match controls. No significant difference was observed in chromosomal aberrations and DNA damage. A significant increase was observed in sister chromatid exchanges (SCEs) Cell among users. The results obtained and the risk of oral contraceptives (OCs) genotoxicity have been discussed.Keywords: Oral contraceptives; Chromosomal aberrations; DNA damage; Sister chromatid exchanges; Human lymphocyte

Serum biochemical profile of two broiler strains supplemented with vitamin E, raw ginger (Zingiber officinale) and L-carnitine under high ambient temperatures

In this study, the authors evaluated the comparative effects of dietary supplementation of ginger (Zingiber officinale), vitamin E and L-carnitine on certain blood parameters of two strains of broilers in summer. A total of 320 broiler chicks (Hubbard and Cobb) were divided into two groups. The two groups were subdivided into four subgroups with four replicates with 10 chicks per replicate. In each strain subgroup was kept as control while other subgroups were provided with ginger (2%), L-carnitine (500 mg/kg) or vitamin E (250 mg/kg) in the basal diet up to 42 days old. Supplementation of the diet with vitamin E, ginger and L-carnitine significantly decreased mean cholesterol, alanine aminotransferase (ALT), glucose, triglyceride, low density lipoprotein (LDL), and increased high density lipoprotein (HDL) and serum protein concentrations. The results of vitamin E were comparatively better than those of the other two feed additives. The blood biochemical parameters did not vary between the broiler strains. From the findings of the current study, it was concluded that high ambient temperature had a negative effect on broiler hepatic and lipid profiles, and the supplementation of diets with vitamin E, ginger and L-carnitine improved broiler blood biochemical parameters.Keywords: Cholesterol, glucose, liver health, antioxidants, heat stres

Enhanced production of subtilisin of Pyrococcus furiosus expressed in Escherichia coli using autoinducing medium

A subtilisin gene identified in the reported genome sequence of Pyrococcus furiosus was amplified and inserted in pET-22b(+) vector to produce the recombinant plasmid pET-SB. Escherichia coli BL-21 (DE3)CodonPlus was transformed with this plasmid and the enzyme was expressed up to 30% of the total cell protein on induction with IPTG. The expressed protein appeared at a position corresponding to ~20 kDaon SDS-PAGE as compared to theoretical molecular mass of 17.6 kDa. This aberrant electrophoresis mobility could be due to specific amino acid composition of the protein. Auto-induction with lactose also produced a similar level of expression but the total amount of the enzyme produced was 2.4 foldgreater than that when produced with IPTG induction. This was due to a higher cell density obtainable in the auto-inducing medium. The enzyme expressed in the insoluble state could be partially refolded after denaturation with urea at high pH. This study reports for the first time high-level expression ofsubtilisin of P. furiosus in E. coli using an auto-inducing medium