Search results for: water resource scarcity
1979 Improving the Uptake of Community-Based Multidrug-Resistant Tuberculosis Treatment Model in Nigeria
Authors: A. Abubakar, A. Parsa, S. Walker
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Despite advances made in the diagnosis and management of drug-sensitive tuberculosis (TB) over the past decades, treatment of multidrug-resistant tuberculosis (MDR-TB) remains challenging and complex particularly in high burden countries including Nigeria. Treatment of MDR-TB is cost-prohibitive with success rate generally lower compared to drug-sensitive TB and if care is not taken it may become the dominant form of TB in future with many treatment uncertainties and substantial morbidity and mortality. Addressing these challenges requires collaborative efforts thorough sustained researches to evaluate the current treatment guidelines, particularly in high burden countries and prevent progression of resistance. To our best knowledge, there has been no research exploring the acceptability, effectiveness, and cost-effectiveness of community-based-MDR-TB treatment model in Nigeria, which is among the high burden countries. The previous similar qualitative study looks at the home-based management of MDR-TB in rural Uganda. This research aimed to explore patient’s views and acceptability of community-based-MDR-TB treatment model and to evaluate and compare the effectiveness and cost-effectiveness of community-based versus hospital-based MDR-TB treatment model of care from the Nigerian perspective. Knowledge of patient’s views and acceptability of community-based-MDR-TB treatment approach would help in designing future treatment recommendations and in health policymaking. Accordingly, knowledge of effectiveness and cost-effectiveness are part of the evidence needed to inform a decision about whether and how to scale up MDR-TB treatment, particularly in a poor resource setting with limited knowledge of TB. Mixed methods using qualitative and quantitative approach were employed. Qualitative data were obtained using in-depth semi-structured interviews with 21 MDR-TB patients in Nigeria to explore their views and acceptability of community-based MDR-TB treatment model. Qualitative data collection followed an iterative process which allowed adaptation of topic guides until data saturation. In-depth interviews were analyzed using thematic analysis. Quantitative data on treatment outcomes were obtained from medical records of MDR-TB patients to determine the effectiveness and direct and indirect costs were obtained from the patients using validated questionnaire and health system costs from the donor agencies to determine the cost-effectiveness difference between community and hospital-based model from the Nigerian perspective. Findings: Some themes have emerged from the patient’s perspectives indicating preference and high acceptability of community-based-MDR-TB treatment model by the patients and mixed feelings about the risk of MDR-TB transmission within the community due to poor infection control. The result of the modeling from the quantitative data is still on course. Community-based MDR-TB care was seen as the acceptable and most preferred model of care by the majority of the participants because of its convenience which in turn enhanced recovery, enables social interaction and offer more psychosocial benefits as well as averted productivity loss. However, there is a need to strengthen this model of care thorough enhanced strategies that ensure guidelines compliance and infection control in order to prevent the progression of resistance and curtail community transmission.Keywords: acceptability, cost-effectiveness, multidrug-resistant TB treatment, community and hospital approach
Procedia PDF Downloads 1221978 Large Eddy Simulations for Flow Blurring Twin-Fluid Atomization Concept Using Volume of Fluid Method
Authors: Raju Murugan, Pankaj S. Kolhe
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The present study is mainly focusing on the numerical simulation of Flow Blurring (FB) twin fluid injection concept was proposed by Ganan-Calvo, which involves back flow atomization based on global bifurcation of liquid and gas streams, thus creating two-phase flow near the injector exit. The interesting feature of FB injector spray is an insignificant effect of variation in atomizing air to liquid ratio (ALR) on a spray cone angle. Besides, FB injectors produce a nearly uniform spatial distribution of mean droplet diameter and are least susceptible to variation in thermo-physical properties of fuels, making it a perfect candidate for fuel flexible combustor development. The FB injector working principle has been realized through experimental flow visualization techniques only. The present study explores potential of ANSYS Fluent based Large Eddy Simulation(LES) with volume of fluid (VOF) method to investigate two-phase flow just upstream of injector dump plane and spray quality immediate downstream of injector dump plane. Note that, water and air represent liquid and gas phase in all simulations and ALR is varied by changing the air mass flow rate alone. Preliminary results capture two phase flow just upstream of injector dump plane and qualitative agreement is observed with the available experimental literature.Keywords: flow blurring twin fluid atomization, large eddy simulation, volume of fluid, air to liquid ratio
Procedia PDF Downloads 2141977 First Earth Size
Authors: Ibrahim M. Metwally
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Have you ever thought that earth was not the same earth we live on? Was it bigger or smaller? Was it a great continent surrounded by huge ocean as Alfred Wegener (1912) claimed? Earth is the most amazing planet in our Milky Way galaxy and may be in the universe. It is the only deformed planet that has a variable orbit around the sun and the only planet that has water on its surface. How did earth deformation take place? What does cause earth to deform? What are the results of earth deformation? How does its orbit around the sun change? First earth size computation can be achieved only considering the quantum of iron and nickel rested into earth core. This paper introduces a new theory “Earth expansion Theory”. The principles of “Earth Expansion Theory” are leading to new approaches and concepts to interpret whole earth dynamics and its geological and environmental changes. This theory is not an attempt to unify the two divergent dominant theories of continental drift, plate tectonic theory and earth expansion theory. The new theory is unique since it has a mathematical derivation, explains all the change to and around earth in terms of geological and environmental changes, and answers all unanswered questions in other theories. This paper presents the basic of the introduced theory and discusses the mechanism of earth expansion and how it took place, the forces that made the expansion. The mechanisms of earth size change from its spherical shape with radius about 3447.6 km to an elliptic shape of major radius about 6378.1 km and minor radius of about 6356.8 km and how it took place, are introduced and discussed. This article also introduces, in a more realistic explanation the formation of oceans and seas, the preparation of river formation. It also addresses the role of iron in earth size enlargement process within the continuum mechanics framework.Keywords: earth size, earth expansion, continuum mechanics, continental and ocean formation
Procedia PDF Downloads 4481976 Green Electrochemical Nitration of Bioactive Compounds: Biological Evaluation with Molecular Modelling
Authors: Sara Torabi, Sadegh Khazalpour, Mahdi Jamshidi
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Nitro aromatic compounds are valuable materials because of their applications in the preparation of chemical intermediates for the synthesis of dyes, plastics, perfumes, energetic materials, and pharmaceuticals. Chemical and electrochemical procedures are reported for nitration of aromatic compounds. Flavonoid derivatives are present in many vegetables and fruits and are constituent of many common pharmaceuticals and dietary supplements. Electrochemistry provides very versatile means for the electrosynthesis, mechanistic and kinetic studies. To the best of our knowledge, and despite the importance of these compounds in numerous scientific fields, there are no reports on the electrochemical nitration of Quercetin derivatives. Herein, we describe a green electrochemical synthesis of a nitro compound. In this work, electrochemical oxidation of Quercetin has been studied in the presence of nitrite ion as a nucleophile in acetate buffer solution (c = 0.2 M, pH = 6.0), by means of cyclic voltammetry and controlled-potential coulometry. The results indicate the participation of produced o-benzoquinones in Michael reaction with nitrite ion (in the divided cell) to form the corresponding nitro diol (EC mechanism). The purity of product and characterization was done using ¹H NMR, ¹³C NMR, FTIR spectroscopic techniques. The presented strategies use a water/ethanol mixture as solvent. Ethanol as cosolvent was also used in the previous studies because of its low cost, safety, easy availability, recyclability, bioproductability, and biodegradability. These strategies represent a one-pot and facile process for the synthesis of nitro compound in high yield and purity under green conditions.Keywords: electrochemical synthesis, green chemistry, cyclic voltammetry, molecular docking
Procedia PDF Downloads 1441975 The Compositional Effects on Electrospinning of Gelatin and Polyvinyl-alcohol Mixed Nanofibers
Authors: Yi-Chun Wu, Nai-Yun Chang, Chuan LI
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This study investigates a feasible range of composition for the mixture of gelatin and polyvinyl alcohol to form nanofibers by electrospinning. Gelatin, one of the most available naturally derived hydrogels of amino acids, is a popular choice for food additives, cosmetic ingredients, biomedical implants, or dressing of its non-toxic and biodegradable nature. Nevertheless, synthetic hydrogel polyvinyl alcohol has long been used as a thickening agent for adhesion purposes. Many biomedical devices are also containing polyvinyl-alcohol as a major content, such as eye drops and contact lenses. To discover appropriate compositions of gelatin and polyvinyl-alcohol for electrospun nanofibers, polymer solutions of different volumetric ratios between gelatin and polyvinyl alcohol were prepared for electrospinning. The viscosity, surface tension, pH value, and electrical conductance of polymer solutions were measured. On the nanofibers, the vibrational modes of molecular structures in nanofibers were investigated by Fourier-transform infrared spectroscopy. The morphologies and surface chemical elements of fibers were examined by the scanning electron microscope and the energy-dispersive X-ray spectroscopy. The hydrophilicity of nanofiberswas evaluated by the water contact angles on the surface of the fibers. To further test the biotoxicity of nanofibers, an in-vitro 3T3 fibroblasts culture further tested the biotoxicity of the electrospun nanofibers. Throughstatistical analyses of the experimental data, it is found that the polyvinyl-alcohol rich composition (the volumetric ratio of gelatin/polyvinyl-alcohol < 1) would be a preferable choice for the formation of nanofibers by the current setup of electrospinning. These electrospun nanofibers tend to be hydrophilic with no biotoxicity threat to the 3T3 fibroblasts.Keywords: gelatin, polyvinyl-alcohol, nanofibers, electrospinning, spin coating
Procedia PDF Downloads 851974 Eco-City Planning and Urban Design in Lagos, Nigeria: Recent Innovations, Trends, Concerns, Challenges, and Solutions
Authors: Dahunsi Michael Oluseyi
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This paper aims to extensively examine eco-city planning and urban design in Lagos, Nigeria. It will delve into the city's developments, challenges, and potential solutions to offer insights for sustainable urban growth within the rapidly expanding urban landscape. The research will scrutinize recent innovations, emerging trends, and practical remedies to promote ecological sustainability within an urban framework. It will encompass a more in-depth review of current literature, case studies, and qualitative analyses, thereby augmenting the depth and breadth of the research. The objectives are to assess the current eco-city planning initiatives and urban design trends in Lagos, Nigeria, considering the city's unique characteristics and challenges. To identify and analyze the challenges encountered during the implementation of eco-friendly urban developments in Lagos, to explore and evaluate the innovative and practical solutions that are implemented to promote sustainability within the city, to provide comprehensive insights and actionable recommendations for policymakers, urban planners, and other stakeholders involved in sustainable urban development in Lagos, the rapid urbanization of Lagos has brought forth a myriad of challenges, including a burgeoning population, inadequate infrastructure, waste management issues, and environmental pollution. Eco-city planning has emerged as a promising approach to addressing these obstacles, striving to create urban spaces that are more habitable, resource-efficient, and environmentally friendly. This research holds substantial importance in exploring the application of eco-city planning principles within a megacity like Lagos. Analyzing recent innovations, trends, concerns, challenges, and solutions provides invaluable insights for policymakers, urban planners, and stakeholders dedicated to fostering sustainable urban development. The methodologies employed in this research are structured to embrace a multifaceted and intricate approach, aiming to facilitate a comprehensive understanding of the complexities inherent in eco-city planning and urban design in Lagos, Nigeria. This methodological framework is designed to encompass various diverse strategies and analytical tools to effectively capture the multidimensional aspects of sustainable urban development. It involves an in-depth analysis of academic publications, governmental reports, and urban planning documents to highlight global eco-city planning trends and gather Lagos-specific insights through a detailed exploration of eco-friendly initiatives and projects in Lagos to evaluate successes, challenges, and strategies for addressing environmental concerns by engaging key stakeholders, including urban planners, policymakers, environmental experts, and residents, to collect firsthand perspectives, concerns, and insights. Also, a thorough analysis will be carried out on data collected from literature reviews, case studies, interviews, and surveys used to extract prevalent patterns, challenges, and innovative solutions from diverse sources. This study aims to contribute to the discourse on sustainable urban development by offering a comprehensive analysis of eco-city planning in Lagos and providing practical recommendations for a more sustainable urban future.Keywords: eco-friendly, innovation, sustainability, stakeholders
Procedia PDF Downloads 621973 Sheathed Cotton Fibers: Material for Oil-Spill Cleanup
Authors: Benjamin M Dauda, Esther Ibrahim, Sylvester Gadimoh, Asabe Mustapha, Jiyah Mohammed
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Despite diverse optimization techniques on natural hydrophilic fibers, hydrophobic synthetic fibers are still the best oil sorption materials. However, these hydrophobic fibers are not biodegradable, making their disposal problematic. To this end, this work sets out to develop Nonwoven sorbents from epoxy-coated Cotton fibers. As a way of improving the compatibility of the crude oil and reduction of moisture absorption, cotton fibers were coated with epoxy resin by immersion in acetone-thinned epoxy solution. A needle-punching machine was used to convert the fibers into coherent nonwoven sheets. An oil sorption experiment was then carried out. The result indicates that the developed epoxy-modified sorbent has a higher crude oil-sorption capacity compared with those of untreated cotton and commercial polypropylene sorbents. Absorption Curves show that the coated fiber and polypropylene sorbent saturated faster than the uncoated cotton fiber pad. The result also shows that the coated cotton sorbent adsorbed crude faster than the polypropylene sorbent, and the equilibrium exhaustion was also higher. After a simple mechanical squeezing process, the Nonwoven pads could be restored to their original form and repeatedly recycled for oil/water separation. The results indicate that the cotton-coated non-woven pads hold promise for the cleanup of oil spills. Our data suggests that the sorption behaviors of the epoxy-coated Nonwoven pads and their crude oil sorption capacity are relatively stable under various environmental conditions compared to the commercial sheet.Keywords: oil spill, adsorption, cotton, epoxy, nonwoven
Procedia PDF Downloads 551972 Use of Quasi-3D Inversion of VES Data Based on Lateral Constraints to Characterize the Aquifer and Mining Sites of an Area Located in the North-East of Figuil, North Cameroon
Authors: Fofie Kokea Ariane Darolle, Gouet Daniel Hervé, Koumetio Fidèle, Yemele David
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The electrical resistivity method is successfully used in this paper in order to have a clearer picture of the subsurface of the North-East ofFiguil in northern Cameroon. It is worth noting that this method is most often used when the objective of the study is to image the shallow subsoils by considering them as a set of stratified ground layers. The problem to be solved is very often environmental, and in this case, it is necessary to perform an inversion of the data in order to have a complete and accurate picture of the parameters of the said layers. In the case of this work, thirty-three (33) Schlumberger VES have been carried out on an irregular grid to investigate the subsurface of the study area. The 1D inversion applied as a preliminary modeling tool and in correlation with the mechanical drillings results indicates a complex subsurface lithology distribution mainly consisting of marbles and schists. Moreover, the quasi-3D inversion with lateral constraint shows that the misfit between the observed field data and the model response is quite good and acceptable with a value low than 10%. The method also reveals existence of two water bearing in the considered area. The first is the schist or weathering aquifer (unsuitable), and the other is the marble or the fracturing aquifer (suitable). The final quasi 3D inversion results and geological models indicate proper sites for groundwaters prospecting and for mining exploitation, thus allowing the economic development of the study area.Keywords: electrical resistivity method, 1D inversion, quasi 3D inversion, groundwaters, mining
Procedia PDF Downloads 1551971 Comparison of Methods for the Synthesis of Eu+++, Tb+++, and Tm+++ Doped Y2O3 Nanophosphors by Sol-Gel and Hydrothermal Methods for Bioconjugation
Authors: Ravindra P. Singh, Drupad Ram, Dinesh K. Gupta
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Rare earth ions doped metal oxides are a class of luminescent materials which have been proved to be excellent for applications in field emission displays and cathode ray tubes, plasma display panels. Under UV irradiation Eu+++ doped Y2O3 is a red phosphor and Tb+++ doped Y 2O3 is a green phosphor. It is possible that, due to their high quantum efficiency, they might serve as improved luminescent markers for identification of biomolecules, as already reported for CdSe and CdSe/ZnS nanocrystals. However, for any biological applications these particle powders must be suspended in water while retaining their phosphorescence. We hereby report synthesis and characterization of Eu+++ and Tb+++ doped yttrium oxide nanoparticles by sol-gel and hydrothermal processes. Eu+++ and Tb+++ doped Y2O3 nanoparticles have been synthesized by hydrothermal process using yttrium oxo isopropoxide [Y5O(OPri)13] (crystallized twice) and it’s acetyl acetone modified product [Y(O)(acac)] as precursors. Generally the sol-gel derived metal oxides are required to be annealed to the temperature ranging from 400°C-800°C in order to develop crystalline phases. However, this annealing also results in the development of aggregates which are undesirable for bio-conjugation experiments. In the hydrothermal process, we have achieved crystallinity of the nanoparticles at 300°C and the development of crystalline phases has been found to be proportional to the time of heating of the reactor. The average particle sizes as calculated from XRD were found to be 28 nm, 32 nm, and 34 nm by hydrothermal process. The particles were successfully suspended in chloroform in the presence of trioctyl phosphene oxide and TEM investigations showed the presence of single particles along with agglomerates.Keywords: nanophosphors, Y2O3:Eu+3, Y2O3:Tb+3, sol-gel, hydrothermal method, TEM, XRD
Procedia PDF Downloads 4021970 Crystallized Colored Towels Obtained by Special Coloration of Yarns
Authors: Hasan Eskin, Gizem Özmen, A. Nazmi Çeler
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When we examine the home textile development process, it follows a parallel line with the other textile products especially in the garment fabrics in terms of raw materials, production technologies and pattern characteristics. As a result, the expectations of people regarding textile, comfort, pattern (texture) and color properties are increasing. One of the places where comfort is most sought after is bath, pool, sea and baths. In addition to the material and technique that make up the physical structure in woven fabrics, color has an impressive importance with its strong effects. Color is the most prominent element in the fabric, and the color and texture are visually reinforcing. Evaluation of color in fabric is a personal phenomenon. Factors that determine color determination in fabric are the amount of color used, color ratio and its relationship with other colors. In this project; Considering the effect of color dimensions on human, we are talking about the crystallized colored towel that we developed in terms of comfort and texture properties. The basis of the effect created in the towel; It is formed by bending the yarn from its own special blend and the harmonious appearance of the natural crystallized rainbow colors with the pattern effect it determines on the warp yarns by using the weft yarns in the weaving. In addition, by using different weaving techniques and colors, alternatives can be created and personalized patterns can be created. One side of the towel determines the properties related to color, while the pile part determines the comfort characteristics with its soft touch and water absorbency.Keywords: color effect, comfort, towel, weaving technique
Procedia PDF Downloads 1621969 Study of the Suitability for the Use of Gravel in the Regions around Araz River in Karabakh as a Concrete Aggregate
Authors: S. B. Shahmarova, F. N. Iskandarli, J. T. Zeynalov, F. N. Mammadov, M. M. Mirzayev, F. Y. Bayramov
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The physical, mechanical, and chemical properties of aggregates play an important role in the production of ready-mixed concrete. Furthermore, the alkali-silicate reaction of aggregates is one of the essential factors in construction projects for the durability and longer service life of buildings and construction structures to be built. It is necessary to use the aggregates from the liberated regions of Karabakh and East Zangazur in the preparation of concretes to be produced for reconstruction and renovation projects in those regions. In this regard, the study of the physical and mechanical properties of aggregates in the regions around the Araz River (Fuzuli, Jabrayil, and Zangilan) became a significant issue. So, gravel samples were taken from seven different sources located in the regions around Araz River, where the quarries are planned to be built. The chemical oxide composition of the samples was determined, water absorption and specific gravity tests, chloride, alkali-silicate reaction tests, aggregate crushing strength test, Los Angeles, and frost resistance (into the solution of MgSO₄ and Na₂SO₄) tests were performed, and the results were evaluated in accordance with the relevant standards. As a result, it was determined that the aggregates in the regions around the Araz River (Fuzuli, Jabrayil, and Zangilan) conform to the relative standards and can be used effectively in the production of various concretes to be used for the projects in Karabakh.Keywords: aggregates of the regions around Araz River (Fuzuli, Jabrayil, and Zangilan), physical and mechanical properties, alkali-silicate reaction, Karabakh, Azerbaijan
Procedia PDF Downloads 931968 Biodiesel Production Using Eggshells as a Catalyst
Authors: Ieva Gaide, Violeta Makareviciene
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Increasing environmental pollution is caused by various factors, including the usage of vehicles. Legislation is focused on the increased usage of renewable energy sources for fuel production. Electric car usage is also important; however, it is relatively new and expensive transport. It is necessary to increase the amount of renewable energy in the production of diesel fuel, whereas many agricultural machineries are powered by diesel, as are water vehicles. For this reason, research on biodiesel production is relevant. The majority of studies globally are related to the improvement of conventional biofuel production technologies by applying the transesterification process of oil using alcohol and catalyst. Some of the more recent methods to produce biodiesel are based on heterogeneous catalysis, which has the advantage of easy separation of catalyst from the final product. It is known that a large amount of eggshells is treated as waste; therefore, it is eliminated in landfills without any or with minimal pre-treatment. CaO, which is known as a good catalyst for biodiesel synthesis, is a key component of eggshells. In the present work, we evaluated the catalytic efficiency of eggshells and determined the optimal transesterification conditions to obtain biodiesel that meets the standards. Content CaO in eggshells was investigated. Response surface methodology was used to determine the optimal reaction conditions. Three independent variables were investigated: the molar ratio of alcohol to oil, the amount of the catalyst, and the duration of the reaction. It was obtained that the optimum transesterification conditions when the methanol and eggshells as a heterogeneous catalyst are used and the process temperature is 64°C are the following: the alcohol-to-oil molar ratio 10.93:1, the reaction duration 9.48 h, and the catalyst amount 6.80 wt%. Under these conditions, 97.79 wt% of the ester yield was obtained.Keywords: heterogeneous catalysis, eggshells, biodiesel, oil
Procedia PDF Downloads 1211967 Towards a Measuring Tool to Encourage Knowledge Sharing in Emerging Knowledge Organizations: The Who, the What and the How
Authors: Rachel Barker
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The exponential velocity in the truly knowledge-intensive world today has increasingly bombarded organizations with unfathomable challenges. Hence organizations are introduced to strange lexicons of descriptors belonging to a new paradigm of who, what and how knowledge at individual and organizational levels should be managed. Although organizational knowledge has been recognized as a valuable intangible resource that holds the key to competitive advantage, little progress has been made in understanding how knowledge sharing at individual level could benefit knowledge use at collective level to ensure added value. The research problem is that a lack of research exists to measure knowledge sharing through a multi-layered structure of ideas with at its foundation, philosophical assumptions to support presuppositions and commitment which requires actual findings from measured variables to confirm observed and expected events. The purpose of this paper is to address this problem by presenting a theoretical approach to measure knowledge sharing in emerging knowledge organizations. The research question is that despite the competitive necessity of becoming a knowledge-based organization, leaders have found it difficult to transform their organizations due to a lack of knowledge on who, what and how it should be done. The main premise of this research is based on the challenge for knowledge leaders to develop an organizational culture conducive to the sharing of knowledge and where learning becomes the norm. The theoretical constructs were derived and based on the three components of the knowledge management theory, namely technical, communication and human components where it is suggested that this knowledge infrastructure could ensure effective management. While it is realised that it might be a little problematic to implement and measure all relevant concepts, this paper presents effect of eight critical success factors (CSFs) namely: organizational strategy, organizational culture, systems and infrastructure, intellectual capital, knowledge integration, organizational learning, motivation/performance measures and innovation. These CSFs have been identified based on a comprehensive literature review of existing research and tested in a new framework adapted from four perspectives of the balanced score card (BSC). Based on these CSFs and their items, an instrument was designed and tested among managers and employees of a purposefully selected engineering company in South Africa who relies on knowledge sharing to ensure their competitive advantage. Rigorous pretesting through personal interviews with executives and a number of academics took place to validate the instrument and to improve the quality of items and correct wording of issues. Through analysis of surveys collected, this research empirically models and uncovers key aspects of these dimensions based on the CSFs. Reliability of the instrument was calculated by Cronbach’s a for the two sections of the instrument on organizational and individual levels.The construct validity was confirmed by using factor analysis. The impact of the results was tested using structural equation modelling and proved to be a basis for implementing and understanding the competitive predisposition of the organization as it enters the process of knowledge management. In addition, they realised the importance to consolidate their knowledge assets to create value that is sustainable over time.Keywords: innovation, intellectual capital, knowledge sharing, performance measures
Procedia PDF Downloads 1951966 Bacterial Cellulose: A New Generation Antimicrobial Wound Dressing Biomaterial
Authors: Bhavana V. Mohite, Satish V. Patil
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Bacterial cellulose (BC) is an alternative for plant cellulose (PC) that prevents global warming leads to preservation of nature. Although PC and BC have the same chemical structure, BC is superior with its properties like its size, purity, porosity, degree of polymerization, crystallinity and water holding capacity, thermal stability etc. On this background the present study focus production and applications of BC as antimicrobial wound dressing material. BC was produced by Gluconoacetobacter hansenii (strain NCIM 2529) under shaking condition and statistically enhanced upto 7.2 g/l from 3.0 g/l. BC was analyzed for its physico mechanical, structural and thermal characteristics. BC produced at shaking condition exhibits more suitable properties in support to its high performance applications. The potential of nano silver impregnated BC was determined for sustained release modern antimicrobial wound dressing material by swelling ratio, mechanical properties and antimicrobial activity against Staphylococcus aureus. BC in nanocomposite form with other synthetic polymer like PVA shows improvement in its properties such as swelling ratio (757% to 979%) and sustainable release of antibacterial agent. The high drug loading and release potential of BC was evidenced in support to its nature as antimicrobial wound dressing material. The nontoxic biocompatible nature of BC was confirmed by MTT assay on human epidermal cells with 90% cell viability that allows its application as a regenerative biomaterial. Thus, BC as a promising new generation antimicrobial wound dressing material was projected.Keywords: agitated culture, biopolymer, gluconoacetobacter hansenii, nanocomposite
Procedia PDF Downloads 3011965 Project Management and International Development: Competencies for International Assignment
Authors: M. P. Leroux, C. Coulombe
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Projects are popular vehicles through which international aid is delivered in developing countries. To achieve their objectives, many northern organizations develop projects with local partner organizations in the developing countries through technical assistance projects. International aid and international development projects precisely have long been criticized for poor results although billions are spent every year. Little empirical research in the field of project management has the focus on knowledge transfer in international development context. This paper focuses particularly on personal dimensions of international assignees participating in project within local team members in the host country. We propose to explore the possible links with a human resource management perspective in order to shed light on the less research problematic of knowledge transfer in development cooperation projects. The process leading to capacity building being far complex, involving multiple dimensions and far from being linear, we propose here to assess if traditional research on expatriate in multinational corporations pertain to the field of project management in developing countries. The following question is addressed: in the context of international development project cooperation, what personal determinants should the selection process focus when looking to fill a technical assistance position in a developing country? To answer that question, we first reviewed the literature on expatriate in the context of inter organizational knowledge transfer. Second, we proposed a theoretical framework combining perspectives of development studies and management to explore if parallels can be draw between traditional international assignment and technical assistance project assignment in developing countries. We conducted an exploratory study using case studies from technical assistance initiatives led in Haiti, a country in Central America. Data were collected from multiple sources following qualitative study research methods. Direct observations in the field were allowed by local leaders of six organization; individual interviews with present and past international assignees, individual interview with local team members, and focus groups were organized in order to triangulate information collected. Contrary from empirical research on knowledge transfer in multinational corporations, results tend to show that technical expertise rank well behind many others characteristics. Results tend to show the importance of soft skills, as a prerequisite to succeed in projects where local team have to collaborate. More importantly, international assignees who were talking knowledge sharing instead of knowledge transfer seemed to feel more satisfied at the end of their mandate than the others. Reciprocally, local team members who perceived to have participated in a project with an expat looking to share instead of aiming to transfer knowledge seemed to describe the results of project in more positive terms than the others. Results obtained from this exploratory study open the way for a promising research agenda in the field of project management. It emphasises the urgent need to achieve a better understanding on the complex set of soft skills project managers or project chiefs would benefit to develop, in particular, the ability to absorb knowledge and the willingness to share one’s knowledge.Keywords: international assignee, international project cooperation, knowledge transfer, soft skills
Procedia PDF Downloads 1421964 Macrocycles Enable Tuning of Uranyl Electrochemistry by Lewis Acids
Authors: Amit Kumar, Davide Lionetti, Victor Day, James Blakemore
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Capture and activation of the water-soluble uranyl dication (UO22+) remains a challenging problem, as few rational approaches are available for modulating the reactivity of this species. Here, we report the divergent synthesis of heterobimetallic complexes in which UO22+ is held in close proximity to a range of redox-inactive metals by tailored macrocyclic ligands. Crystallographic and spectroscopic studies confirm assembly of homologous UVI(μ-OAr)2Mn+ cores with a range of mono-, di-, and trivalent Lewis acids (Mn+). X-ray diffraction (XRD) and cyclic voltammetry (CV) data suggest preferential binding of K+ in an 18-crown-6-like cavity and Na+ in a 15-crown-5-like cavity, both appended to Schiff-base type sites that selectively bind UO22+. CV data demonstrate that the UVI/UV reduction potential in these complexes shifts positive and the rate of electron transfer decreases with increasing Lewis acidity of the incorporated redox-inactive metals. Moreover, spectroelectrochemical studies confirm the formation of [UV] species in the case of monometallic UO22+ complex, consistent with results from prior studies. However, unique features were observed during spectroelectrochemical studies in the presence of the K+ ion, suggesting new insights into electronic structure may be accessible with the heterobimetallic complexes. Overall, these findings suggest that interactions with Lewis acids could be effectively leveraged for rational tuning of the electronic and thermochemical properties of the 5f elements, reminiscent of strategies more commonly employed with 3d transition metals.Keywords: electrochemistry, Lewis acid, macrocycle, uranyl
Procedia PDF Downloads 1421963 Creation of a Trust-Wide, Cross-Speciality, Virtual Teaching Programme for Doctors, Nurses and Allied Healthcare Professionals
Authors: Nelomi Anandagoda, Leanne J. Eveson
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During the COVID-19 pandemic, the surge in in-patient admissions across the medical directorate of a district general hospital necessitated the implementation of an incident rota. Conscious of the impact on training and professional development, the idea of developing a virtual teaching programme was conceived. The programme initially aimed to provide junior doctors, specialist nurses, pharmacists, and allied healthcare professionals from medical specialties and those re-deployed from other specialties (e.g., ophthalmology, GP, surgery, psychiatry) the knowledge and skills to manage the deteriorating patient with COVID-19. The programme was later developed to incorporate the general internal medicine curriculum. To facilitate continuing medical education whilst maintaining social distancing during this period, a virtual platform was used to deliver teaching to junior doctors across two large district general hospitals and two community hospitals. Teaching sessions were recorded and uploaded to a common platform, providing a resource for participants to catch up on and re-watch teaching sessions, making strides towards reducing discrimination against the professional development of less than full-time trainees. Thus, creating a learning environment, which is inclusive and accessible to adult learners in a self-directed manner. The negative impact of the pandemic on the well-being of healthcare professionals is well documented. To support the multi-disciplinary team, the virtual teaching programme evolved to included sessions on well-being, resilience, and work-life balance. Providing teaching for learners across the multi-disciplinary team (MDT) has been an eye-opening experience. By challenging the concept that learners should only be taught within their own peer groups, the authors have fostered a greater appreciation of the strengths of the MDT and showcased the immense wealth of expertise available within the trust. The inclusive nature of the teaching and the ease of joining a virtual teaching session has facilitated the dissemination of knowledge across the MDT, thus improving patient care on the frontline. The weekly teaching programme has been running for over eight months, with ongoing engagement, interest, and participation. As described above, the teaching programme has evolved to accommodate the needs of its learners. It has received excellent feedback with an appreciation of its inclusive, multi-disciplinary, and holistic nature. The COVID-19 pandemic provided a catalyst to rapidly develop novel methods of working and training and widened access/exposure to the virtual technologies available to large organisations. By merging pedagogical expertise and technology, the authors have created an effective online learning environment. Although the authors do not propose to replace face-to-face teaching altogether, this model of virtual multidisciplinary team, cross-site teaching has proven to be a great leveler. It has made high-quality teaching accessible to learners of different confidence levels, grades, specialties, and working patterns.Keywords: cross-site, cross-speciality, inter-disciplinary, multidisciplinary, virtual teaching
Procedia PDF Downloads 1701962 Effects of Particle Size Distribution on Mechanical Strength and Physical Properties in Engineered Quartz Stone
Authors: Esra Arici, Duygu Olmez, Murat Ozkan, Nurcan Topcu, Furkan Capraz, Gokhan Deniz, Arman Altinyay
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Engineered quartz stone is a composite material comprising approximately 90 wt.% fine quartz aggregate with a variety of particle size ranges and `10 wt.% unsaturated polyester resin (UPR). In this study, the objective is to investigate the influence of particle size distribution on mechanical strength and physical properties of the engineered stone slabs. For this purpose, granular quartz with two particle size ranges of 63-200 µm and 100-300 µm were used individually and mixed with a difference in ratios of mixing. The void volume of each granular packing was measured in order to define the amount of filler; quartz powder with the size of less than 38 µm, and UPR required filling inter-particle spaces. Test slabs were prepared using vibration-compression under vacuum. The study reports that both impact strength and flexural strength of samples increased as the mix ratio of the particle size range of 63-200 µm increased. On the other hand, the values of water absorption rate, apparent density and abrasion resistance were not affected by the particle size distribution owing to vacuum compaction. It is found that increasing the mix ratio of the particle size range of 63-200 µm caused the higher porosity. This led to increasing in the amount of the binder paste needed. It is also observed that homogeneity in the slabs was improved with the particle size range of 63-200 µm.Keywords: engineered quartz stone, fine quartz aggregate, granular packing, mechanical strength, particle size distribution, physical properties.
Procedia PDF Downloads 1471961 Phosphate Bonded Hemp (Cannabis sativa) Fibre Composites
Authors: Stephen O. Amiandamhen, Martina Meinken, Luvuyo Tyhoda
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The properties of Hemp (Cannabis sativa) in phosphate bonded composites were investigated in this research. Hemp hurds were collected from the Hemporium institute for research, South Africa. The hurds were air-dried and shredded using a hammer mill. The shives were screened into different particle sizes and were treated separately with 5% solution of acetic anhydride and sodium hydroxide. The binding matrix was prepared using a reactive magnesia, phosphoric acid, class S fly ash and unslaked lime. The treated and untreated hemp fibers were mixed thoroughly in different ratios with the inorganic matrix. Boric acid and excess water were used to retard and control the rate of the reaction and the setting of the binder. The Hemp composite was formed in a rectangular mold and compressed at room temperature at a pressure of 100KPa. After de-molding the composites, they were cured in a conditioning room for 96 h. Physical and mechanical tests were conducted to evaluate the properties of the composites. A central composite design (CCD) was used to determine the best conditions to optimize the performance of the composites. Thereafter, these combinations were applied in the production of the composites, and the properties were evaluated. Scanning electron microscopy (SEM) was used to carry out the advance examination of the behavior of the composites while X-ray diffractometry (XRD) was used to analyze the reaction pathway in the composites. The results revealed that all properties of phosphate bonded Hemp composites exceeded the LD-1 grade classification of particle boards. The proposed product can be used for ceiling, partitioning, wall claddings and underlayment.Keywords: CCD, fly ash, magnesia, phosphate bonded hemp composites, phosphoric acid, unslaked lime
Procedia PDF Downloads 4351960 Service Delivery Disparity Conundrum at Winnie Madikizela Mandela Local Municipality: Exploration of the Enhanced Future
Authors: Mandisi Matyana
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Although the South African local government is doing all the best in ensuring improved service delivery for the citizens, service delivery disparity still remains the real challenge for other municipalities. The unequal distribution of services within municipal wards is causing unequal happiness among the citizens; hence others do enjoy different provided municipal services, while others do not. It is acknowledged that less access to municipal services infringes one’s rights, such as the right to human dignity and the right to life. Some of the municipal services are basic services and they are the mainstay of human survival, such as water, housing, etc. It is quite evident that the service delivery disparity could be caused by the various factors within the local municipality affairs, including both administrative and political factors. Therefore, this study is undertaken to check and evaluate the main foundations of service delivery disparity in ensuring equal development of the state, particularly for local communities. The study used the qualitative method to collect the data from the citizens of Winnie Madikizela Mandela Local Municipality. An extensive literature was also conducted in understanding the causes of service delivery disparity. Study findings prove that the service delivery disparity could be caused by factors such as political interference in administration, corruption and fraud, elevated unemployment levels, inadequate institutional capacity, etc. Therefore, the study recommends strong community participation and constant external supervision in the local government so as to encourage openness in local government to ensure fair administration towards services to be provided.Keywords: administration, development, municipal services, service delivery disparity, Winnie Madikizela Mandela local municipality
Procedia PDF Downloads 1101959 The Utilization of Banana Leaves as a Substitute for Synthetic Mosquito Repellant
Authors: Beryl Apondi Obola
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Introduction: Mosquitoes are known to transmit various diseases such as malaria, dengue fever, and Zika virus. Mosquito repellents are commonly used to prevent mosquito bites. However, some of these repellents contain chemicals that can be harmful to human health and the environment. Therefore, there is a need to find alternative mosquito repellents that are safe and effective. Objective: The objective of this research is to investigate the effectiveness of banana leaves as an alternative mosquito repellent on Plasmodium falciparum and Plasmodium vivax. Methodology: The research will be conducted in two phases. In the first phase, the repellent properties of banana leaves will be tested in a laboratory setting. The leaves will be crushed and mixed with water to extract the active ingredients. The extract will be tested against mosquitoes in a controlled environment. The number of mosquitoes that are repelled by the extract will be recorded. In the second phase, the effectiveness of the banana leaf extract will be tested in the field. The extract will be applied to the skin of human volunteers, and the number of mosquito bites will be recorded. The results will be compared to a commercially available mosquito repellent. Expected Outcomes: The expected outcome of this research is to determine whether banana leaves can be used as an effective mosquito repellent. If the results are positive, banana leaves could be used as an alternative to chemical-based mosquito repellents. Conclusion: Banana leaves have been used for various purposes in traditional medicine. This research aims to investigate the potential of banana leaves as an alternative mosquito repellent. The results of this research could have significant implications for public health and the environmentKeywords: banana leaf extract, mosquito repellant, plasmodium falciparum, public health
Procedia PDF Downloads 921958 A Study of Laminar Natural Convection in Annular Spaces between Differentially Heated Horizontal Circular Cylinders Filled with Non-Newtonian Nano Fluids
Authors: Behzad Ahdiharab, Senol Baskaya, Tamer Calisir
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Heat exchangers are one of the most widely used systems in factories, refineries etc. In this study, natural convection heat transfer using nano-fluids in between two cylinders is numerically investigated. The inner and outer cylinders are kept at constant temperatures. One of the most important assumptions in the project is that the working fluid is non-Newtonian. In recent years, the use of nano-fluids in industrial applications has increased profoundly. In this study, nano-Newtonian fluids containing metal particles with high heat transfer coefficients have been used. All fluid properties such as homogeneity has been calculated. In the present study, solutions have been obtained under unsteady conditions, base fluid was water, and effects of various parameters on heat transfer have been investigated. These parameters are Rayleigh number (103 < Ra < 106), power-law index (0.6 < n < 1.4), aspect ratio (0 < AR < 0.8), nano-particle composition, horizontal and vertical displacement of the inner cylinder, rotation of the inner cylinder, and volume fraction of nanoparticles. Results such as the internal cylinder average and local Nusselt number variations, contours of temperature, flow lines are presented. The results are also discussed in detail. From the validation study performed it was found that a very good agreement exists between the present results and those from the open literature. It was found out that the heat transfer is always affected by the investigated parameters. However, the degree to which the heat transfer is affected does change in a wide range.Keywords: heat transfer, circular space, non-Newtonian, nano fluid, computational fluid dynamics.
Procedia PDF Downloads 4151957 The Impacts of Land Use Change and Extreme Precipitation Events on Ecosystem Services
Authors: Szu-Hua Wang
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Urban areas contain abundant potential biochemical storages and renewable and non-renewable flows. Urban natural environments for breeding natural assets and urban economic development for maintaining urban functions can be analyzed form the concept of ecological economic system. Land use change and ecosystem services change are resulting from the interactions between human activities and environments factually. Land use change due to human activities is the major cause of climate change, leading to serious impacts on urban ecosystem services, including provisioning services, regulating services, cultural services and supporting services. However, it lacks discussion on the interactions among urban land use change, ecosystem services change, and extreme precipitation events. Energy synthesis can use the same measure standard unit, solar energy, for different energy resources (e.g. sunlight, water, fossil fuels, minerals, etc.) and analyze contributions of various natural environmental resources on human economic systems. Therefore, this research adopts the concept of ecological, economic systems and energy synthesis for analyzing dynamic spatial impacts of land use change on ecosystem services, using the Taipei area as a case study. The analysis results show that changes in land use in the Taipei area, especially the conversion of natural lands and agricultural lands to urban lands, affect the ecosystem services negatively. These negative effects become more significant during the extreme precipitation events.Keywords: urban ecological economic system, extreme precipitation events, ecosystem services, energy
Procedia PDF Downloads 1901956 Condensation Heat Transfer and Pressure Drop of R-134a Flowing inside Dimpled Tubes
Authors: Kanit Aroonrat, Somchai Wongwises
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A heat exchanger is one of the vital parts in a wide variety of applications. The tube with surface modification is generally referred to as an enhanced tube. With this, the thermal performance of the heat exchanger is improved. A dimpled tube is one of many kinds of enhanced tube. The heat transfer and pressure drop of two-phase flow inside dimpled tubes have received little attention in the literature, despite of having an important role in the development of refrigeration and air conditioning systems. As a result, the main aim of this study is to investigate the condensation heat transfer and pressure drop of refrigerant-134a flowing inside dimpled tubes. The test section is a counter-flow double-tube heat exchanger, which the refrigerant flows in the inner tube and water flows in the annulus. The inner tubes are one smooth tube and three dimpled tubes with different helical pitches. All test tubes are made from copper with an inside diameter of 8.1 mm and length of 1500 mm. The experiments are conducted over mass fluxes ranging from 300 to 500 kg/m²s, heat flux ranging from 10 to 20 kW/m², and condensing temperature ranging from 40 to 50 ˚C. The results show that all dimpled tubes provide higher heat transfer coefficient and frictional pressure drop compared to the smooth tube. In addition, the heat transfer coefficient and frictional pressure drop increase with decreasing of helical pitch. It can be observed that the dimpled tube with lowest helical pitch yields the heat transfer enhancement in the range of 60-89% with the frictional pressure drop increase of 289-674% in comparison to the smooth tube.Keywords: condensation, dimpled tube, heat transfer, pressure drop
Procedia PDF Downloads 2151955 Comparative Study of Properties of Iranian Historical Gardens by Focusing on Climate
Authors: Malihe Ahmadi
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Nowadays, stress, tension and neural problems are among the most important concerns of the present age. The environment plays key role on improving mental health and reducing stress of citizens. Establishing balance and appropriate relationship between city and natural environment is of the most important approaches of present century. Type of approach and logical planning for urban green spaces as one of the basic sections of integration with nature, not only plays key role on quality and efficiency of comprehensive urban planning; but also it increases the system of distributing social activities and happiness and lively property of urban environments that leads to permanent urban development. The main purpose of recovering urban identity is considering culture, history and human life style in past. This is a documentary-library research that evaluates the historical properties of Iranian gardens in compliance with climate condition. Results of this research reveal that in addition to following Iranian gardens from common principles of land lot, structure of flowers and plants, water, specific buildings during different ages, the role of climate at different urban areas is among the basics of determining method of designing green spaces and different buildings located at diverse areas i.e. Iranian gardens are a space for merging natural and artificial elements that has inseparable connection with semantic principles and guarantees different functions. Some of the necessities of designing present urban gardens are including: recognition and recreation.Keywords: historical gardens, climate, properties of Iranian gardens, Iran
Procedia PDF Downloads 3971954 Urban Dust Influence on the Foliar Surface and Biochemical Constituents of Selected Plants in the National Capital Region of Delhi, India
Authors: G. P. Gupta, B. Kumar, S. Singh, U. C. Kulshrestha
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Very high loadings of atmospheric dust in the Indian region contribute to remarkably higher levels of particulate matter. During dry weather conditions which prevail most of the year, dustfall is deposited onto the foliar surfaces affecting their morphology, stomata and biochemical constituents. This study reports chemical characteristics of dustfall, its effect on foliar morphology and biochemical constituents of two medicinal plants i.e. Morus (Morus alba) and Arjun (Terminalia arjuna) in the urban environment of National Capital Region (NCR) of Delhi at two sites i.e. Jawaharlal Nehru University (residential) and Sahibabad (industrial). Atmospheric dust was characterized for major anions (F-, Cl-, NO3-, SO4--) and cations (Na+, NH4+, K+, Mg++, Ca++) along with the biochemical parameters Chl a, Chl b, total chlorophyll, carotenoid, total soluble sugar, relative water content (RWC), pH, and ascorbic acid. The results showed that the concentrations of major ions in dustfall were higher at the industrial site as compared to the residential site due to the higher level of anthropogenic activities. Both the plant species grown at industrial site had significantly lower values of chlorophyll ‘a’, chlorophyll ‘b’, total chlorophyll, carotenoid but relatively higher values of total soluble sugar and ascorbic acid indicating stressful conditions due to industrial and vehicular emissions.Keywords: dustfall, urban environment, biochemical constituents, atmospheric dust
Procedia PDF Downloads 3051953 Allium Cepa Extract Provides Neuroprotection Against Ischemia Reperfusion Induced Cognitive Dysfunction and Brain Damage in Mice
Authors: Jaspal Rana, Alkem Laboratories, Baddi, Himachal Pradesh, India Chitkara University, Punjab, India
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Oxidative stress has been identified as an underlying cause of ischemia-reperfusion (IR) related cognitive dysfunction and brain damage. Therefore, antioxidant based therapies to treat IR injury are being investigated. Allium cepa L. (onion) is used as culinary medicine and is documented to have marked antioxidant effects. Hence, the present study was designed to evaluate the effect of A. cepa outer scale extract (ACE) against IR induced cognition and biochemical deficit in mice. ACE was prepared by maceration with 70% methanol and fractionated into ethylacetate and aqueous fractions. Bilateral common carotid artery occlusion for 10 min followed by 24 h reperfusion was used to induce cerebral IR injury. Following IR injury, ACE (100 and 200 mg/kg) was administered orally to animals for 7 days once daily. Behavioral outcomes (memory and sensorimotor functions) were evaluated using Morris water maze and neurological severity score. Cerebral infarct size, brain thiobarbituric acid reactive species, reduced glutathione, and superoxide dismutase activity was also determined. Treatment with ACE significantly ameliorated IR mediated deterioration of memory and sensorimotor functions and rise in brain oxidative stress in animals. The results of the present investigation revealed that ACE improved functional outcomes after cerebral IR injury, which may be attributed to its antioxidant properties.Keywords: stroke, neuroprotection, ischemia reperfusion, herbal drugs
Procedia PDF Downloads 1061952 Effects of the Food Colour Erythrosine on Thyroid Gland Function in Experimental Rats
Authors: Maha M.Saber, Eitedal Daoud, Moetazza M. Alshafei, Lobna M. Abd El-Latif
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Children in the third world consumes many food products colored red like sweets and soft drink without knowing its effect on health or the type of color used in these products Erythrosine (ER,FD & C Red No.3) is one of the most common coloring agent used in these products and in coloring cherry in compotes. The possible adverse effect of erythrosine ER on the thyroid gland function is investigated in albino rats. Forty-five adult male albino rats were divided to three groups two groups will receive ER orally in doses 68 and I36mg/kg respectively. Third group will receive distilled water for three months Sections of thyroid glands were examined for histopathological, morphometric analysis and MIB-I Ki67 (proliferative marker). Serum concentration of triiodothyronine (T3), Thyroxin (T4) and thyrotrophin (TSH) were determined, results showed histological changes in the two treatment groups versus control group in the group with 68mg/kg dose show vaculation of the cytoplasm of follicular cells and pleomorphism of their nuclei. While the other treated group {136mg /kg} showed congestion of blood vessels, hyperplasia of the interstitial cells and increased multilayer of the follicular cells. Highly significant increase in the mean area of the thyroid follicles in both treated groups compared to control group.Erythrosine treated groups showed a very highly significant decrease (P < 0.001) in serum concentration of T3 and T 4 while TSH showed a very highly significant increase versus control.Keywords: erythrosine, thyroid, morphometrics, proliferative marker
Procedia PDF Downloads 4071951 Synthesis and Characterization of Lactic Acid Grafted TiO2 Nanocomposites
Authors: Qasar Saleem
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The aim of this project was to synthesize and analyze Polylactic acid-grafted TiO2 nanocomposite. When dispersed at the nanoscale TiO2 can behave as see through transparent UV filters and thermomechanical materials. The synthesis plan involved three stages. First, dispersion of TiO2 white powder in water/ethanol solvent system. Second grafting TiO2 surface by oligomers of lactic acid aimed at changing its surface features. Third polymerization of lactic acid monomer with grafted TiO2 in the presence of anhydrous stannous chloride as a catalyst. Polylactic acid grafted-TiO2 nanocomposite was synthesized by melt polycondensation in situ of lactic acid onto titanium oxide (TiO2) nanoparticles surface. The product was characterized by TGA, DSC, FTIR, and UV analysis and degradation observation. An idea regarding bonds between the grafting polymer and surface modified titanium oxide nanoparticles. Characteristics peaks of Ti–carbonyl bond, the related intensities of the Fourier transmission absorption peaks of graft composite, the melt and decomposition behavior stages of Polylactic acid-grafted TiO2 nanocomposite convinced that oligomers of polylactic acid were chemically bonded on the surface of TiO2 nanoparticles. Through grafting polylactic acid, the Polylactic acid grafted -TiO2 sample shown good absorption in UV region and degradation behavior under normal atmospheric conditions. Regaining transparency of degraded white opaque Polylactic acid-grafted TiO2 nanocomposite on heating was another character. Polylactic acid-grafted TiO2 nanocomposite will be a potential candidate in future for biomedical, UV shielding and environment friendly material.Keywords: condensation, nanocomposites, oligomers, polylactic
Procedia PDF Downloads 2091950 Igbo Art: A Reflection of the Igbo’s Visual Culture
Authors: David Osa-Egonwa
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Visual culture is the expression of the norms and social behavior of a society in visual images. A reflection simply shows you how you look when you stand before a mirror, a clear water or stream. The mirror does not alter, improve or distort your original appearance, neither does it show you a caricature of what stands before it, this is the case with visual images created by a tribe or society. The ‘uli’ is hand drawn body design done on Igbo women and speaks of a culture of body adornment which is a practice that is appreciated by that tribe. The use of pattern of the gliding python snake ‘ije eke’ or ‘ijeagwo’ for wall painting speaks of the Igbo culture as one that appreciates wall paintings based on these patterns. Modern life came and brought a lot of change to the Igbo-speaking people of Nigeria. Change cloaked in the garment of Westernization has influenced the culture of the Igbos. This has resulted in a problem which is a break in the cultural practice that has also affected art produced by the Igbos. Before the colonial masters arrived and changed the established culture practiced by the Igbos, visual images were created that retained the culture of this people. To bring this point to limelight, this paper has adopted a historical method. A large number of works produced during pre and post-colonial era which range from sculptural pieces, paintings and other artifacts, just to mention a few, were studied carefully and it was discovered that the visual images hold the culture or aspects of the culture of the Igbos in their renditions and can rightly serve as a mirror of the Igbo visual culture.Keywords: artistic renditions, historical method, Igbo visual culture, changes
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