Search results for: sociocultural influence
1946 Evaluating Gene-Gene Interaction among Nicotine Dependence Genes on the Risk of Oral Clefts
Authors: Mengying Wang, Dongjing Liu, Holger Schwender, Ping Wang, Hongping Zhu, Tao Wu, Terri H Beaty
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Background: Maternal smoking is a recognized risk factor for nonsyndromic cleft lip with or without cleft palate (NSCL/P). It has been reported that the effect of maternal smoking on oral clefts is mediated through genes that influence nicotine dependence. The polymorphisms of cholinergic receptor nicotinic alpha (CHRNA) and beta (CHRNB) subunits genes have previously shown strong associations with nicotine dependence. Here, we attempted to investigate whether the above genes are associated with clefting risk through testing for potential gene-gene (G×G) and gene-environment (G×E) interaction. Methods: We selected 120 markers in 14 genes associated with nicotine dependence to conduct transmission disequilibrium tests among 806 Chinese NSCL/P case-parent trios ascertained in an international consortium which conducted a genome-wide association study (GWAS) of oral clefts. We applied Cordell’s method using “TRIO” package in R to explore G×G as well as G×E interaction involving environmental tobacco smoke (ETS) based on conditional logistic regression model. Results: while no SNP showed significant association with NSCL/P after Bonferroni correction, we found signals for G×G interaction between 10 pairs of SNPs in CHRNA3, CHRNA5, and CHRNB4 (p<10-8), among which the most significant interaction was found between RS3743077 (CHRNA3) and RS11636753 (CHRNB4, p<8.2×10-12). Linkage disequilibrium (LD) analysis revealed only low level of LD between these markers. However, there were no significant results for G×ETS interaction. Conclusion: This study fails to detect association between nicotine dependence genes and NSCL/P, but illustrates the importance of taking into account potential G×G interaction for genetic association analysis in NSCL/P. This study also suggests nicotine dependence genes should be considered as important candidate genes for NSCL/P in future studies.Keywords: Gene-Gene Interaction, Maternal Smoking, Nicotine Dependence, Non-Syndromic Cleft Lip with or without Cleft Palate
Procedia PDF Downloads 3381945 Identifying and Prioritizing Critical Success Factors (Csfs) in Retaining and Developing Knowledge Workers in Oil and Gas Project–Based Companies
Authors: Ehsan Samimi, Mohammaa Ali Shahosseeni, Ali Abasltian, Shahriar Shafaghi
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Background/Objectives: Voluntary turnover and early retirement request by specialists and experienced people in project-based organizations (PBO) has caused many problems in finding suitable experts to execute the projects. Methods/Statistical analysis: The present study is a descriptive and applied research. Research population consists of KWs in oil and gas PBO. The engineers in these organizations were considered as research sample. Interviews and questionnaire were used to gather information. Interviews with experts were used to identify factors and questionnaires were utilized to identify the importance and prioritization. 72 factors were identified and categorized into 9 groups within organizational and HR initiative levels. Results: Results of the research indicate the priority of each group of factors according to the proposed model in the view of KWs in oil, gas and petrochemical industries. On this basis, the following factors have the highest effect ratio based on the respondents’ point of view: 1. knowledge management 2. Performance appraisal system 3. Communication 4.Training and development 5.Job design and analysis 6. Employment policies 7. Career planning 8. Project/organizational factors 9. Salary and rewards. Additionally, in each group the priority of effective sub-factors has been identified as the result of the research .The results support the definitions of KWs and influence of factors examined and specified by similar studies in retention and development of KWs. The high importance of knowledge management and low rank for salary and rewards can be mentioned as example in this regard. Despite the priority of each group of factors the uniqueness of the result is due to identification of effective factors in the specific industry (oil and gas) and type of organization (PBO). Conclusion/Application: The findings of present study can be used to devise plans for retaining and developing KWs in PBO especially in oil and gas industry.Keywords: project–based organizations, knowledge workers, HR management, turnover, retaining and developing employees
Procedia PDF Downloads 2941944 Integrating Human Rights into Countering Violent Extremism: A Comparative Analysis of Women Without Borders and Hedayah Initiatives
Authors: Portia Muehlbauer
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This paper examines the evolving landscape of preventing and countering violent extremism (PCVE) by delving into the growing importance of integrating human rights principles into violence prevention strategies on the local, community level. This study sheds light on the underlying theoretical frameworks of violent extremism and the influence of gender while investigating the intersection between human rights preservation and violent extremism prevention. To gain practical insight, the research focuses on two prominent international non-governmental organizations, Women without Borders (WwB) and Hedayah, and their distinct PCVE initiatives. WwB adopts a gender-sensitive approach, implementing parental education programs that empower mothers in at-risk communities to prevent the spread of violent extremism. In contrast, Hedayah takes an indirect route, employing capacity building programs that enhance the capabilities of educators, social workers, and psychologists in early intervention, rehabilitation and reintegration efforts. Qualitative data for this comparative analysis was collected through an extensive four-month internship at WwB during the fall of 2020, a three-month internship at Hedayah in the spring of 2021, a thought-provoking semi-structured interview with the executive director of WwB, personal field notes, and a comprehensive discourse analysis of the prevailing literature on human rights considerations in PCVE practices. This study examines the merits and challenges of integrating human rights into PCVE programming through the lens of both organizations, WwB and Hedayah. The findings of this study will inform policymakers, practitioners, and researchers on the intricate relationship between human rights protection and effective PCVE strategies.Keywords: preventing and countering violent extremism, human rights, counterterrorism, peacebuilding, capacity building programs, gender studies
Procedia PDF Downloads 631943 Infant Care Practice in Hadiya Culture: Case Study of Harche Auyaya
Authors: Dawit Thomas
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Feeding and weaning practices vary from culture to culture and depend on different child-rearing values. The socio-cultural dimensions that influence the acceptable infant feeding practices are varied and complex. Understanding cultural differences in beliefs and practices relating to infant feeding is important to enhance designing programs for delivering successful psychological, social, physiological and economic well-being of mothers and infants. The main purpose of this study was exploring mothers infant feeding practices in the context of Hadiyya culture. After purposively selecting Harche Huyaya Uyaya Kebele eight infant feeding mothers were selected using snowball sampling technique. The study employed interviews and focus group discussion. The study found out early initiation and prolonged breastfeeding and early complementary feeding in some instances immediately after birth. In addition, infants were not forced to wean unless the mothers encounter pressing issues like pregnancy and health related problems. Furthermore, the main weaning techniques were putting unpleasant materials on the tip of nipples and sending infants to grandparents home. The study also found out gender difference in weaning, i.e., early initiation of weaning for girls. This can be indicative of gender-based bias on weaning practice. Finally, health extension workers, office of women and children affairs and Hadiyya Zone Tourism office should organize awareness raising programs to preserve vital infant feeding practices like prolonged breastfeeding and length of weaning. In addition, the offices should raise awareness among communities on negative side effects of sending infant to grandparents home that may weaken infant-mothers attachment and create favorable ground for the development of phobia.Keywords: feeding, infant, practices, weaning
Procedia PDF Downloads 3301942 Occupational Health and Well-Being of Healthcare Workers at Tertiary Care Hospitals in Lahore, Pakistan: A Comparison of Public and Private Sector
Authors: Mehwish Sarfaraz Ahmad
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Background: There is a prevailing perception in Pakistan that private hospitals offer better services than government hospitals. Unfortunately, Pakistan faces challenges in providing efficient healthcare due to limited resources and management capabilities, resulting in demotivation among healthcare workers. Aim: The purpose of this study was to conduct a comprehensive assessment of the occupational health and well-being of healthcare workers in both public and private sector tertiary care hospitals in Lahore, Pakistan, to compare the well-being of healthcare professionals in these two sectors and investigate the influence of workplace culture and experiences on their overall health. Methods: A cross-sectional study was conducted using a validated International Questionnaire, and data from 440 participants was collected using a stratified random sampling technique from a diverse group of healthcare professionals from the public and private tertiary care hospitals in Lahore, Pakistan. The researcher conducted a comparative analysis using appropriate statistical tests, such as Anova, t-tests, chi-square tests, and regression analysis, to explore potential relationships between various factors. Results: The majority of respondents (70.2%) reported their health as "Good" or "Very good, a small percentage (8.2%) rated their health as "Poor," while 24.1% considered their health as "Fair". 39.6% reported being satisfied with their workplace culture, while a majority of 60.4% indicated being unsatisfied with their workplace culture. Results showed that workplace culture has a positive correlation with the overall health and well-being of healthcare professionals. The study found significant differences in health ratings, prevalence of chronic health conditions, workplace culture, and safety perceptions between healthcare professionals in public and private sector tertiary care hospitals. Conclusion: The study's findings emphasize the significance of promoting a positive workplace culture, ensuring workplace safety, and addressing chronic health conditions among healthcare workers.Keywords: occupational health and well-being, workplace culture, frequency of fatigue, availabity of benefits
Procedia PDF Downloads 691941 Alumni Experiences of How Their Undergraduate Medical Education Instilled and Fostered a Commitment to Community-Based Work in Later Life: A Sequential Exploratory Mixed-Methods Study
Authors: Harini Aiyer, Kalyani Premkumar
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Health professionals are the key players who can help achieve the goals of population health equity. Social accountability (SA) of health professionals emphasizes their role in addressing issues of equity in the population they serve. Therefore, health professional education must focus on instilling SA in health professionals. There is limited literature offering a longitudinal perspective of how students sustain the practice of SA in later life. This project aims to identify the drivers of social accountability among physicians. This study employed an exploratory mixed methods design (QUAL-> Quant) to explore alumni perceptions and experiences. The qualitative data, collected via 20 in-depth, semi-structured interviews, provided an understanding of the perceptions of the alumni regarding the influence of their undergraduate learning environment on their SA. This was followed by a quantitative portion -a questionnaire designed from the themes identified from the qualitative data. Emerging themes from the study highlighted community-centered education and a focus on social and preventative medicine in both curricular and non-curricular facilitators of SA among physicians. Curricular components included opportunities to engage with the community, such as roadside clinics, community-orientation programs, and postings at a secondary hospital. Other facilitators that emerged were the faculty leading by example, a subsidized fee structure, and a system that prepared students for practice in rural and remote areas. The study offers a fresh perspective and dimension on how SA is addressed by medical schools. The findings may be adapted by medical schools to understand how their own SA initiatives have been sustained among physicians over the long run.Keywords: community-based work, global health, health education, medical education, providing health in remote areas, social accountability
Procedia PDF Downloads 831940 Numerical Solution of Portfolio Selecting Semi-Infinite Problem
Authors: Alina Fedossova, Jose Jorge Sierra Molina
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SIP problems are part of non-classical optimization. There are problems in which the number of variables is finite, and the number of constraints is infinite. These are semi-infinite programming problems. Most algorithms for semi-infinite programming problems reduce the semi-infinite problem to a finite one and solve it by classical methods of linear or nonlinear programming. Typically, any of the constraints or the objective function is nonlinear, so the problem often involves nonlinear programming. An investment portfolio is a set of instruments used to reach the specific purposes of investors. The risk of the entire portfolio may be less than the risks of individual investment of portfolio. For example, we could make an investment of M euros in N shares for a specified period. Let yi> 0, the return on money invested in stock i for each dollar since the end of the period (i = 1, ..., N). The logical goal here is to determine the amount xi to be invested in stock i, i = 1, ..., N, such that we maximize the period at the end of ytx value, where x = (x1, ..., xn) and y = (y1, ..., yn). For us the optimal portfolio means the best portfolio in the ratio "risk-return" to the investor portfolio that meets your goals and risk ways. Therefore, investment goals and risk appetite are the factors that influence the choice of appropriate portfolio of assets. The investment returns are uncertain. Thus we have a semi-infinite programming problem. We solve a semi-infinite optimization problem of portfolio selection using the outer approximations methods. This approach can be considered as a developed Eaves-Zangwill method applying the multi-start technique in all of the iterations for the search of relevant constraints' parameters. The stochastic outer approximations method, successfully applied previously for robotics problems, Chebyshev approximation problems, air pollution and others, is based on the optimal criteria of quasi-optimal functions. As a result we obtain mathematical model and the optimal investment portfolio when yields are not clear from the beginning. Finally, we apply this algorithm to a specific case of a Colombian bank.Keywords: outer approximation methods, portfolio problem, semi-infinite programming, numerial solution
Procedia PDF Downloads 3101939 Connecting Teachers in a Web-Based Professional Development Community in Crisis Time: A Knowledge Building Approach
Authors: Wei Zhao
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The pandemic crisis disrupted normal classroom practices so that the constraints of the traditional practice became apparent. This turns out to be new opportunities for technology-based learning and teaching. However, how the technology supports the preschool teachers go through this sudden crisis and how preschool teachers conceived of the use of technology, appropriate and design technological artifacts as a mediator of knowledge construction in order to suit young children’s literacy level are rarely explored. This study addresses these issues by looking at the influence of a web-supported teacher community on changes/shifts in preschool teachers’ epistemological beliefs and practices. This teachers’ professional development community was formulated before the pandemic time and developed virtually throughout the home-based learning caused by Covid-19. It served as a virtual and asynchronous community for those teachers to collaboratively plan for and conduct online lessons using the knowledge-building approach for the purpose of sustaining children’s learning curiosity and opening up new learning opportunities during the lock-down period. The knowledge-building approach helps to increase teachers’ collective responsibility to collaboratively work on shared educational goals in the teacher community and awareness of noticing new ideas or innovations in their classroom. Based on the data collected across five months during and after the lock-down period and the activity theory, results show a dynamic interplay between the evolution of the community culture, the growth of teacher community and teachers’ identity transformation and professional development. Technology is useful in this regard not only because it transforms the geographical distance and new gathering guidelines after the outbreak of pandemic into new ways of communal communication and collaboration. More importantly, while teachers selected, monitored and adapted the technology, it acts as a catalyst for changes in teachers’ old teaching practices and epistemological dispositions.Keywords: activity theory, changes in epistemology and practice, knowledge building, web-based teachers’ professional development community
Procedia PDF Downloads 1831938 Representation of Memory of Forced Displacement in Central and Eastern Europe after World War II in Polish and German Cinemas
Authors: Ilona Copik
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The aim of this study is to analyze the representation of memories of the forced displacement of Poles and Germans from the eastern territories in 1945 as depicted by Polish and German feature films between the years 1945-1960. The aftermath of World War II and the Allied agreements concluded at Yalta and Potsdam (1945) resulted in changes in national borders in Central and Eastern Europe and the large-scale transfer of civilians. The westward migration became a symbol of the new post-war division of Europe, new spheres of influence separated by the Iron Curtain. For years it was a controversial topic in both Poland and Germany due to the geopolitical alignment (the socialist East and capitalist West of Europe), as well as the unfinished debate between the victims and perpetrators of the war. The research premise is to take a comparative view of the conflicted cultures of Polish and German memory, to reflect on the possibility of an international dialogue about the past recorded in film images, and to discover the potential of film as a narrative warning against totalitarian inclinations. Until now, films made between 1945 and 1960 in Poland and the German occupation zones have been analyzed mainly in the context of artistic strategies subordinated to ideology and historical politics. In this study, the intention is to take a critical approach leading to the recognition of how films work as collective memory media, how they reveal the mechanisms of memory/forgetting, and what settlement topoi and migration myths they contain. The main hypothesis is that feature films about forced displacement, in addition to the politics of history - separate in each country - reveal comparable transnational individual experiences: the chaos of migration, the trauma of losing one's home, the conflicts accompanying the familiar/foreign, the difficulty of cultural adaptation, the problem of lost identity, etc.Keywords: forced displacement, Polish and German cinema, war victims, World War II
Procedia PDF Downloads 681937 Rock-Bed Thermocline Storage: A Numerical Analysis of Granular Bed Behavior and Interaction with Storage Tank
Authors: Nahia H. Sassine, Frédéric-Victor Donzé, Arnaud Bruch, Barthélemy Harthong
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Thermal Energy Storage (TES) systems are central elements of various types of power plants operated using renewable energy sources. Packed bed TES can be considered as a cost–effective solution in concentrated solar power plants (CSP). Such a device is made up of a tank filled with a granular bed through which heat-transfer fluid circulates. However, in such devices, the tank might be subjected to catastrophic failure induced by a mechanical phenomenon known as thermal ratcheting. Thermal stresses are accumulated during cycles of loading and unloading until the failure happens. For instance, when rocks are used as storage material, the tank wall expands more than the solid medium during charge process, a gap is created between the rocks and tank walls and the filler material settles down to fill it. During discharge, the tank contracts against the bed, resulting in thermal stresses that may exceed the wall tank yield stress and generate plastic deformation. This phenomenon is repeated over the cycles and the tank will be slowly ratcheted outward until it fails. This paper aims at studying the evolution of tank wall stresses over granular bed thermal cycles, taking into account both thermal and mechanical loads, with a numerical model based on the discrete element method (DEM). Simulations were performed to study two different thermal configurations: (i) the tank is heated homogeneously along its height or (ii) with a vertical gradient of temperature. Then, the resulting loading stresses applied on the tank are compared as well the response of the internal granular material. Besides the study of the influence of different thermal configurations on the storage tank response, other parameters are varied, such as the internal angle of friction of the granular material, the dispersion of particles diameters as well as the tank’s dimensions. Then, their influences on the kinematics of the granular bed submitted to thermal cycles are highlighted.Keywords: discrete element method (DEM), thermal cycles, thermal energy storage, thermocline
Procedia PDF Downloads 4031936 A Multinomial Logistic Regression Analysis of Factors Influencing Couples' Fertility Preferences in Kenya
Authors: Naomi W. Maina
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Fertility preference is a subject of great significance in developing countries. Studies reveal that the preferences of fertility are actually significant in determining the society’s fertility levels because the fertility behavior of the future has a high likelihood of falling under the effect of currently observed fertility inclinations. The objective of this study was to establish the factors associated with fertility preference amongst couples in Kenya by fitting a multinomial logistic regression model against 5,265 couple data obtained from Kenya demographic health survey 2014. Results revealed that the type of place of residence, the region of residence, age and spousal age gap significantly influence desire for additional children among couples in Kenya. There was the notable high likelihood of couples living in rural settlements having similar fertility preference compared to those living in urban settlements. Moreover, geographical disparities such as in northern Kenya revealed significant differences in a couples desire to have additional children compared to Nairobi. The odds of a couple’s desire for additional children were further observed to vary dependent on either the wife or husbands age and to a large extent the spousal age gap. Evidenced from the study, was the fact that as spousal age gap increases, the desire for more children amongst couples decreases. Insights derived from this study would be attractive to demographers, health practitioners, policymakers, and non-governmental organizations implementing fertility related interventions in Kenya among other stakeholders. Moreover, with the adoption of devolution, there is a clear need for adoption of population policies that are County specific as opposed to a national population policy as is the current practice in Kenya. Additionally, researchers or students who have little understanding in the application of multinomial logistic regression, both theoretical understanding and practical analysis in SPSS as well as application on real datasets, will find this article useful.Keywords: couples' desire, fertility, fertility preference, multinomial regression analysis
Procedia PDF Downloads 1831935 The Influence of the Normative Gender Binary in Diversity Management: A Multi-Method Study on Gender Diversity of Diversity Management
Authors: Robin C. Ladwig
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Diversity Management, as a substantial element of Human Resource Management, aims to secure the economic benefit that assumingly comes with a diverse workforce. Consequently, diversity managers focus on the protection of employees and securing equality measurements to assure organisational gender diversity. Gender diversity as one aspect of Diversity Management seems to adhere to gender binarism and cis-normativity. Workplaces are gendered spaces which are echoing the binary gender-normativity presented in Diversity Management, sold under the label of gender diversity. While the expectation of Diversity Management implies the inclusion of a multiplicity of marginalised groups, such as trans and gender diverse people, in current literature and practice, the reality is curated by gender binarism and cis-normativity. The qualitative multi-method research showed a lack of knowledge about trans and gender diverse matters within the profession of Diversity Management and Human Resources. The semi-structured interviews with trans and gender diverse individuals from various backgrounds and occupations in Australia exposed missing considerations of trans and gender diverse experiences in the inclusivity and gender equity of various workplaces. Even if practitioners consider trans and gender diverse matters under gender diversity, the practical execution is limited to gender binary structures and cis-normative actions as the photo-elicit questionnaire with diversity managers, human resource officers, and personnel management demonstrates. Diversity Management should approach a broader source of informed practice by extending their business focus to the knowledge of humanity studies. Humanity studies could include diversity, queer, or gender studies to increase the inclusivity of marginalised groups such as trans and gender diverse employees and people. Furthermore, the definition of gender diversity should be extended beyond the gender binary and cis-normative experience. People may lose trust in Diversity Management as a supportive ally of marginalised employees if the understanding of inclusivity is limited to a gender binary and cis-normativity value system that misrepresents the richness of gender diversity.Keywords: cis-normativity, diversity management, gender binarism, trans and gender diversity
Procedia PDF Downloads 2041934 Exercise Intensity Increasing Appetite, Energy, Intake Energy Expenditure, and Fat Oxidation in Sedentary Overweight Individuals
Authors: Ghalia Shamlan, M. Denise Robertson, Adam Collins
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Appetite control (i.e. control of energy intake) is important for weight maintenance. Exercise contributes to the most variable component of energy expenditure (EE) but its impact is beyond the energy cost of exercise including physiological, behavioural, and appetite effects. Exercise is known to acutely influence effect appetite but evidence as to the independent effect of intensity is lacking. This study investigated the role of exercise intensity on appetite, energy intake (EI), appetite related hormone, fat utilisation and subjective measures of appetite. One hour after a standardised breakfast, 10 sedentary overweight volunteers. Subjects undertook either 8 repeated 60 second bouts of cycling at 95% VO2max (high intensity) or 30 minutes of continuous cycling, at a fixed cadence, equivalent to 50% of the participant’s VO2max (low intensity) in a randomised crossover design. Glucose, NEFA, glucagon-like peptide-1 (GLP-1) were measured fasted, postprandial, and pre and post-exercise. Satiety was assessed subjectively throughout the study using visual analogue scales (VAS). Ad libitum intake of a pasta meal was measured at the end (3-h post-breakfast). Interestingly, there was not significant difference in EE fat oxidation between HI and LI post-exercise. Also, no significant effect of high intensity (HI) was observed on the ad libitum meal, 24h and 48h EI post-exercise. However the mean 24h EI was 3000 KJ lower following HI than low intensity (LI). Despite, no significant differences in hunger score, glucose, NEFA and GLP-1 between both intensities were observed. However, NEFA and GLP-1 plasma level were higher until 30 min post LI. In conclusion, the similarity of EE and oxidation outcomes could give overweight individuals an option to choose between intensities. However, HI could help to reduce EI. There are mechanisms and consequences of exercise in short and long-term appetite control; however, these mechanisms warrant further explanation. These results support the need for future research in to the role of in regulation energy balance, especially for obese people.Keywords: appetite, exercise, food intake, energy expenditure
Procedia PDF Downloads 5071933 Numerical Modelling of 3-D Fracture Propagation and Damage Evolution of an Isotropic Heterogeneous Rock with a Pre-Existing Surface Flaw under Uniaxial Compression
Authors: S. Mondal, L. M. Olsen-Kettle, L. Gross
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Fracture propagation and damage evolution are extremely important for many industrial applications including mining industry, composite materials, earthquake simulations, hydraulic fracturing. The influence of pre-existing flaws and rock heterogeneity on the processes and mechanisms of rock fracture has important ramifications in many mining and reservoir engineering applications. We simulate the damage evolution and fracture propagation in an isotropic sandstone specimen containing a pre-existing 3-D surface flaw in different configurations under uniaxial compression. We apply a damage model based on the unified strength theory and solve the solid deformation and damage evolution equations using the Finite Element Method (FEM) with tetrahedron elements on unstructured meshes through the simulation software, eScript. Unstructured meshes provide higher geometrical flexibility and allow a more accurate way to model the varying flaw depth, angle, and length through locally adapted FEM meshes. The heterogeneity of rock is considered by initializing material properties using a Weibull distribution sampled over a cubic grid. In our model, we introduce a length scale related to the rock heterogeneity which is independent of the mesh size. We investigate the effect of parameters including the heterogeneity of the elastic moduli and geometry of the single flaw in the stress strain response. The generation of three typical surface cracking patterns, called wing cracks, anti-wing cracks and far-field cracks were identified, and these depend on the geometry of the pre-existing surface flaw. This model results help to advance our understanding of fracture and damage growth in heterogeneous rock with the aim to develop fracture simulators for different industry applications.Keywords: finite element method, heterogeneity, isotropic damage, uniaxial compression
Procedia PDF Downloads 2191932 Educational Engineering Tool on Smartphone
Authors: Maya Saade, Rafic Younes, Pascal Lafon
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This paper explores the transformative impact of smartphones on pedagogy and presents a smartphone application developed specifically for engineering problem-solving and educational purposes. The widespread availability and advanced capabilities of smartphones have revolutionized the way we interact with technology, including in education. The ubiquity of smartphones allows learners to access educational resources anytime and anywhere, promoting personalized and self-directed learning. The first part of this paper discusses the overall influence of smartphones on pedagogy, emphasizing their potential to improve learning experiences through mobile technology. In the context of engineering education, this paper focuses on the development of a dedicated smartphone application that serves as a powerful tool for both engineering problem-solving and education. The application features an intuitive and user-friendly interface, allowing engineering students and professionals to perform complex calculations and analyses on their smartphones. The smartphone application primarily focuses on beam calculations and serves as a comprehensive beam calculator tailored to engineering education. It caters to various engineering disciplines by offering interactive modules that allow students to learn key concepts through hands-on activities and simulations. With a primary emphasis on beam analysis, this application empowers users to perform calculations for statically determinate beams, statically indeterminate beams, and beam buckling phenomena. Furthermore, the app includes a comprehensive library of engineering formulas and reference materials, facilitating a deeper understanding and practical application of the fundamental principles in beam analysis. By offering a wide range of features specifically tailored for beam calculation, this application provides an invaluable tool for engineering students and professionals looking to enhance their understanding and proficiency in this crucial aspect of a structural engineer.Keywords: mobile devices in education, solving engineering problems, smartphone application, engineering education
Procedia PDF Downloads 671931 Investigating Informal Vending Practices and Social Encounters along Commercial Streets in Cairo, Egypt
Authors: Dalya M. Hassan
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Marketplaces and commercial streets represent some of the most used and lively urban public spaces. Not only do they provide an outlet for commercial exchange, but they also facilitate social and recreational encounters. Such encounters can be influenced by both formal as well as informal vending activities. This paper explores and documents forms of informal vending practices and how they relate to social patterns that occur along the sidewalks of Commercial Streets in Cairo. A qualitative single case study approach of ‘Midan El Gami’ marketplace in Heliopolis, Cairo is adopted. The methodology applied includes direct and walk-by observations for two main commercial streets in the marketplace. Four zoomed-in activity maps are also done for three sidewalk segments that displayed varying vending and social features. Main findings include a documentation and classification of types of informal vending practices as well as a documentation of vendors’ distribution patterns in the urban space. Informal vending activities mainly included informal street vendors and shop spillovers, either as product or seating spillovers. Results indicated that staying and lingering activities were more prevalent in sidewalks that had certain physical features, such as diversity of shops, shaded areas, open frontages, and product or seating spillovers. Moreover, differences in social activity patterns were noted between sidewalks with street vendors and sidewalks with spillovers. While the first displayed more buying, selling, and people watching activities, the latter displayed more social relations and bonds amongst traders’ communities and café patrons. Ultimately, this paper provides a documentation, which suggests that informal vending can have a positive influence on creating a lively commercial street and on resulting patterns of use on the sidewalk space. The results can provide a basis for further investigations and analysis concerning this topic. This could aid in better accommodating informal vending activities within the design of future commercial streets.Keywords: commercial streets, informal vending practices, sidewalks, social encounters
Procedia PDF Downloads 1641930 Effect of Duration and Frequency on Ground Motion: Case Study of Guwahati City
Authors: Amar F. Siddique
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The Guwahati city is one of the fastest growing cities of the north-eastern region of India, situated on the South Bank of the Brahmaputra River falls in the highest seismic zone level V. The city has witnessed many high magnitude earthquakes in the past decades. The Assam earthquake occurred on August 15, 1950, of moment magnitude 8.7 epicentered near Rima, Tibet was one of the major earthquakes which caused a serious structural damage and widespread soil liquefaction in and around the region. Hence the study of ground motion characteristics of Guwahati city is very essential. In this present work 1D equivalent linear ground response analysis (GRA) has been adopted using Deep soil software. The analysis has been done for two typical sites namely, Panbazar and Azara comprising total four boreholes location in Guwahati city of India. GRA of the sites is carried out by using an input motion recorded at Nongpoh station (recorded PGA 0.048g) and Nongstoin station (recorded PGA 0.047g) of 1997 Indo-Burma earthquake. In comparison to motion recorded at Nongpoh, different amplifications of bedrock peak ground acceleration (PGA) are obtained for all the boreholes by the motion recorded at Nongstoin station; although, the Fourier amplitude ratios (FAR) and fundamental frequencies remain almost same. The difference in recorded duration and frequency content of the two motions mainly influence the amplification of motions thus getting different surface PGA and amplification factor keeping a constant bedrock PGA. From the results of response spectra, it is found that at the period of less than 0.2 sec the ground motion recorded at Nongpoh station will give a high spectral acceleration (SA) on the structures than at Nongstoin station. Again for a period greater than 0.2 sec the ground motion recorded at Nongstoin station will give a high SA on the structures than at Nongpoh station.Keywords: fourier amplitude ratio, ground response analysis, peak ground acceleration, spectral acceleration
Procedia PDF Downloads 1811929 Identification of Deposition Sequences of the Organic Content of Lower Albian-Cenomanian Age in Northern Tunisia: Correlation between Molecular and Stratigraphic Fossils
Authors: Tahani Hallek, Dhaou Akrout, Riadh Ahmadi, Mabrouk Montacer
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The present work is an organic geochemical study of the Fahdene Formation outcrops at the Mahjouba region belonging to the Eastern part of the Kalaat Senan structure in northwestern Tunisia (the Kef-Tedjerouine area). The analytical study of the organic content of the samples collected, allowed us to point out that the Formation in question is characterized by an average to good oil potential. This fossilized organic matter has a mixed origin (type II and III), as indicated by the relatively high values of hydrogen index. This origin is confirmed by the C29 Steranes abundance and also by tricyclic terpanes C19/(C19+C23) and tetracyclic terpanes C24/(C24+C23) ratios, that suggest a marine environment of deposit with high plants contribution. We have demonstrated that the heterogeneity of organic matter between the marine aspect, confirmed by the presence of foraminifera, and the continental contribution, is the result of an episodic anomaly in relation to the sequential stratigraphy. Given that the study area is defined as an outer platform forming a transition zone between a stable continental domain to the south and a deep basin to the north, we have explained the continental contribution by successive forced regressions, having blocked the albian transgression, allowing the installation of the lowstand system tracts. This aspect is represented by the incised valleys filling, in direct contact with the pelagic and deep sea facies. Consequently, the Fahdene Formation, in the Kef-Tedjerouine area, consists of transgressive system tracts (TST) brutally truncated by extras of continental progradation; resulting in a mixed influence deposition having retained a heterogeneous organic material.Keywords: molecular geochemistry, biomarkers, forced regression, deposit environment, mixed origin, Northern Tunisia
Procedia PDF Downloads 2511928 NiFe-Type Catalysts for Anion Exchange Membrane (AEM) Electrolyzers
Authors: Boldin Roman, Liliana Analía Diaz
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As the hydrogen economy continues to expand, reducing energy consumption and emissions while stimulating economic growth, the development of efficient and cost-effective hydrogen production technologies is critical. Among various methods, anion exchange membrane (AEM) water electrolysis stands out due to its potential for using non-noble metal catalysts. The exploration and enhancement of non-noble metal catalysts, such as NiFe-type catalysts, are pivotal for the advancement of AEM technology, ensuring its commercial viability and environmental sustainability. NiFe-type catalysts were synthesized through electrodeposition and characterized both electrochemically and physico-chemically. Various supports, including Ni foam and Ni mesh, were used as porous transport layers (PTLs) to evaluate the effective catalyst thickness and the influence of the PTL in a 5 cm² AEM electrolyzer. This methodological approach allows for a detailed assessment of catalyst performance under operational conditions typical of industrial hydrogen production. The study revealed that electrodeposited non-noble multi-metallic catalysts maintain stable performance as anodes in AEM water electrolysis. NiFe-type catalysts demonstrated superior activity, with the NiFeCoP alloy outperforming others by delivering the lowest overpotential and the highest current density. Furthermore, the use of different PTLs showed significant effects on the electrochemical behavior of the catalysts, indicating that PTL selection is crucial for optimizing performance and efficiency in AEM electrolyzers. Conclusion: The research underscores the potential of non-noble metal catalysts in enhancing efficiency and reducing the costs of AEM electrolysers. The findings highlight the importance of catalyst and PTL optimization in developing scalable and economically viable hydrogen production technologies. Continued innovation in this area is essential for supporting the growth of the hydrogen economy and achieving sustainable energy solutions.Keywords: AEMWE, electrocatalyst, hydrogen production, water electrolysis.
Procedia PDF Downloads 341927 Evaluation of the Spectrum of Cases of Perforation Peritonitis at Jawaharlal Nehru Medical College, Aligarh Muslim University
Authors: Mujahid Ali, Wasif Mohammed Ali, Meraj Ahmad
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Background: Perforation peritonitis is the most common surgical emergency encountered by surgeons all over the world as well as in India. The etiology of perforation peritonitis in India continues to be different from its western counterparts. The aim of this study is to evaluate the spectrum of cases of perforation peritonitis at our hospital. Methods: A prospective study conducted includes three hundred thirtysix patients of perforation peritonitis at J. N. Medical College from October 2015 to July 2017. The patients were admitted, resuscitated and underwent emergency laparotomy. Data were collected in terms of demographic profile, clinical presentations, site of perforations, causes and surgical outcomes. Results: In this study, the most common cause of perforation peritonitis was peptic ulcer disease (43%), followed by enteric perforation (12.8%), tubercular perforation (12.5%), traumatic perforation (11.9%), appendicular perforation (9.8%), amoebic caecal perforation (3%), malignant perforation (1.5%), etc. The sites of perforations were stomach in majority (38.3%), ileum (31%), appendix (8%), duodenum (5.%), caecum (4.4%) ,colon (3%), jejunum (8.5%) and gall bladder (2%). The overall mortality was 21% in our study. Age >50 years (p= <0.0001, OR= 3.9260, CI= 2.2 to 6.9), organ failure (p= <0.0001, OR= 29.2, CI= 14.8 to 57.6), shock (p=<0.0001, OR=20.20, CI= 10.56 to 38.6), diffuse peritonitis (p<0.0015, OR= 6.8810, CI= 2.09 to 22.57) and faecal exudates (p<0.0001) were found to be significant factors affecting mortality. The most common complication associated was superficial wound infection (40%), followed by burst abdomen seen in 21% cases, intra-abdominal sepsis in 18% cases, electrolyte imbalances in 15% cases, anastomotic leak in 6% cases. Conclusion: In this study, stomach is the most common site of perforation with peptic ulcer disease being the most common etiology. Older age, presence of shock, organ failure and faecal peritonitis were the risk factors affecting the mortality of the patients. Early recognition, adequate resuscitation and referral of patients can influence outcome and reduces mortality as well as morbidity.Keywords: etiology, mortality, perforation, spectrum
Procedia PDF Downloads 2581926 Effects of Ensiled Mulberry Leaves and Sun-Dried Mulberry Fruit Pomace on the Composition of Bacteria in Feces of Finishing Steers
Authors: Yan Li, Qingxiang Meng, Bo Zhou, Zhenming Zhou
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The objective of this study was to compare the effects of ensiled mulberry leaves (EML), and sun-dried mulberry fruit pomace (SMFP) on fecal bacterial communities in Simmental crossbred finishing steers fed the following 3 diets: a standard TMR diet, standard diet containing EML and standard diet containing SMFP, and the diets had similar protein and energy levels. Bacterial communities in the fecal content were analyzed using Illumina Miseq sequencing of the V4 region of the 16S rRNA gene amplification. Quantitative real-time PCR was used to detect the selected bacterial species in the feces. Most of the sequences were assigned to phyla Firmicutes (56.67%) and Bacteroidetes(35.90%), followed by Proteobacteria(1.86%), Verrucomicrobia(1.80%) and Tenericutes(1.37%). And the predominant genera included the 5-7N15 (5.91%), CF231 (2.49%), Oscillospira (2.33%), Paludibacter (1.23%) and Akkermansia(1.11%). As for the treatments, no significant differences were observed in Firmicutes (p = 0.28), Bacteroidetes (p = 0.63), Proteobacteria (p = 0.46), Verrucomicrobia (p = 0.17) and Tenericutes (p = 0.75). On the genus level, classified genera with high abundance (more than 0.1%) mainly came from two phyla: Bacteroidetes and Firmicutes. Also no differences were observed in most genera level, 5-7N15 (p = 0.21), CF231 (p = 0.62), Oscillospira (p = 0.9), Paludibacter (p = 0.33) and Akkermansia (p = 0.37), except that rc4-4 were lower in the CON and SMFP groups compared to the EML animals (p = 0.02). Additionally, there were no differences in richness estimate and diversity indices (p > 0.16), and treatments had no significant effect on most selected bacterial species in the fecal (p > 0.06), except that Ruminococcus albus were higher in the EML group (p < 0.01) and Streptococcus bovis were lower in the CON group (p < 0.01). In conclusion, diets supplemented with EML and SMFP have little influence on fecal bacterial community composition in finishing steers.Keywords: fecal bacteria community composition, sequencing, ensiled mulberry leaves (EML), sun-dried mulberry fruit pomace (SMFP)
Procedia PDF Downloads 3251925 Long-Term Effects of Psychosocial Interventions for Adolescents on Depression and Anxiety: A Systematic Review and Meta-Analysis
Authors: Denis Duagi, Ben Carter, Maria Farrelly, Stephen Lisk, June S. L. Brown
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Background: Adolescence represents a distinctive phase of development, and variables linked to this developmental period could affect the efficiency of prevention and treatment for depression and anxiety, as well as the long-term prognosis. The objectives of this study were to investigate the long-term effectiveness of psychosocial interventions for adolescents on depression and anxiety symptoms and to assess the influence of different intervention parameters on the long-term effects. Methods: Searches were carried out on the 11ᵗʰ of August 2022 using five databases (Cochrane Library, Embase, Medline, PsychInfo, Web of Science), as well as trial registers. Randomized controlled trials of psychosocial interventions targeting specifically adolescents were included if they assessed outcomes at 1-year post-intervention or more. The Cochrane risk of bias-2 quality assessment tool was used. The primary outcome was depression, and studies were pooled using a standardised mean difference, with an associated 95% confidence interval, p-value, and I². The study protocol was pre-registered (CRD42022348668). Findings: A total of 57 reports (n= 46,678 participants) were included in the review. Psychosocial interventions led to small reductions in depressive symptoms, with a standardised mean difference (SMD) at 1-year of -0.08 (95%CI -0.20, -0.03, p=0.002, I²=72%), 18-months SMD=-0.12, 95% CI -0.22, -0.01, p=0.03, I²=63%) and 2-years SMD=-0.12 (95% CI -0.20, -0.03, p=0.01, I²=68%). Sub-group analyses indicated that targeted interventions produced stronger effects, particularly when delivered by trained mental health professionals (K=18, SMD=-0.24, 95% CI -0.38, -0.10, p=0.001, I²=60%). No effects were detected for anxiety at any assessment. Conclusion: Psychosocial interventions specifically targeting adolescents were shown to have small but positive effects on depression symptoms but not anxiety symptoms, which were sustained for up to 2 years. These findings highlight the potential population-level preventive effects if such psychosocial interventions become widely implemented in accessible settings such as schools.Keywords: psychosocial, adolescent, interventions, depression, anxiety, meta-analysis, randomized controlled trial
Procedia PDF Downloads 731924 Dynamic Control Theory: A Behavioral Modeling Approach to Demand Forecasting amongst Office Workers Engaged in a Competition on Energy Shifting
Authors: Akaash Tawade, Manan Khattar, Lucas Spangher, Costas J. Spanos
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Many grids are increasing the share of renewable energy in their generation mix, which is causing the energy generation to become less controllable. Buildings, which consume nearly 33% of all energy, are a key target for demand response: i.e., mechanisms for demand to meet supply. Understanding the behavior of office workers is a start towards developing demand response for one sector of building technology. The literature notes that dynamic computational modeling can be predictive of individual action, especially given that occupant behavior is traditionally abstracted from demand forecasting. Recent work founded on Social Cognitive Theory (SCT) has provided a promising conceptual basis for modeling behavior, personal states, and environment using control theoretic principles. Here, an adapted linear dynamical system of latent states and exogenous inputs is proposed to simulate energy demand amongst office workers engaged in a social energy shifting game. The energy shifting competition is implemented in an office in Singapore that is connected to a minigrid of buildings with a consistent 'price signal.' This signal is translated into a 'points signal' by a reinforcement learning (RL) algorithm to influence participant energy use. The dynamic model functions at the intersection of the points signals, baseline energy consumption trends, and SCT behavioral inputs to simulate future outcomes. This study endeavors to analyze how the dynamic model trains an RL agent and, subsequently, the degree of accuracy to which load deferability can be simulated. The results offer a generalizable behavioral model for energy competitions that provides the framework for further research on transfer learning for RL, and more broadly— transactive control.Keywords: energy demand forecasting, social cognitive behavioral modeling, social game, transfer learning
Procedia PDF Downloads 1101923 From Binary Solutions to Real Bio-Oils: A Multi-Step Extraction Story of Phenolic Compounds with Ionic Liquid
Authors: L. Cesari, L. Canabady-Rochelle, F. Mutelet
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The thermal conversion of lignin produces bio-oils that contain many compounds with high added-value such as phenolic compounds. In order to efficiently extract these compounds, the possible use of choline bis(trifluoromethylsulfonyl)imide [Choline][NTf2] ionic liquid was explored. To this end, a multistep approach was implemented. First, binary (phenolic compound and solvent) and ternary (phenolic compound and solvent and ionic liquid) solutions were investigated. Eight binary systems of phenolic compound and water were investigated at atmospheric pressure. These systems were quantified using the turbidity method and UV-spectroscopy. Ternary systems (phenolic compound and water and [Choline][NTf2]) were investigated at room temperature and atmospheric pressure. After stirring, the solutions were let to settle down, and a sample of each phase was collected. The analysis of the phases was performed using gas chromatography with an internal standard. These results were used to quantify the values of the interaction parameters of thermodynamic models. Then, extractions were performed on synthetic solutions to determine the influence of several operating conditions (temperature, kinetics, amount of [Choline][NTf2]). With this knowledge, it has been possible to design and simulate an extraction process composed of one extraction column and one flash. Finally, the extraction efficiency of [Choline][NTf2] was quantified with real bio-oils from lignin pyrolysis. Qualitative and quantitative analysis were performed using gas chromatographic connected to mass spectroscopy and flame ionization detector. The experimental measurements show that the extraction of phenolic compounds is efficient at room temperature, quick and does not require a high amount of [Choline][NTf2]. Moreover, the simulations of the extraction process demonstrate that [Choline][NTf2] process requires less energy than an organic one. Finally, the efficiency of [Choline][NTf2] was confirmed in real situations with the experiments on lignin pyrolysis bio-oils.Keywords: bio-oils, extraction, lignin, phenolic compounds
Procedia PDF Downloads 1111922 Application of Various Methods for Evaluation of Heavy Metal Pollution in Soils around Agarak Copper-Molybdenum Mine Complex, Armenia
Authors: K. A. Ghazaryan, H. S. Movsesyan, N. P. Ghazaryan
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The present study was aimed in assessing the heavy metal pollution of the soils around Agarak copper-molybdenum mine complex and related environmental risks. This mine complex is located in the south-east part of Armenia, and the present study was conducted in 2013. The soils of the five riskiest sites of this region were studied: surroundings of the open mine, the sites adjacent to processing plant of Agarak copper-molybdenum mine complex, surroundings of Darazam active tailing dump, the recultivated tailing dump of “ravine - 2”, and the recultivated tailing dump of “ravine - 3”. The mountain cambisol was the main soil type in the study sites. The level of soil contamination by heavy metals was assessed by Contamination factors (Cf), Degree of contamination (Cd), Geoaccumulation index (I-geo) and Enrichment factor (EF). The distribution pattern of trace metals in the soil profile according to Cf, Cd, I-geo and EF values shows that the soil is much polluted. Almost in all studied sites, Cu, Mo, Pb, and Cd were the main polluting heavy metals, and this was conditioned by Agarak copper-molybdenum mine complex activity. It is necessary to state that the pollution problem becomes pressing as some parts of these highly polluted region are inhabited by population, and agriculture is highly developed there; therefore, heavy metals can be transferred into human bodies through food chains and have direct influence on public health. Since the induced pollution can pose serious threats to public health, further investigations on soil and vegetation pollution are recommended. Finally, Cf calculating based on distance from the pollution source and the wind direction can provide more reasonable results.Keywords: Agarak copper-molybdenum mine complex, heavy metals, soil contamination, enrichment factor (EF), Armenia
Procedia PDF Downloads 2381921 Angiogenic Potential of Collagen Based Biomaterials Implanted on Chick Embryo Chorioallantoic Membrane as Alternative Microenvironment for in Vitro and in Vivo Angiogenesis Assays
Authors: Anca Maria Cimpean, Serban Comsa
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Chick embryo chorioallantoic membrane (CAM) is a well vascularised in vivo experimental model used as a platform for testing the behavior of different implants inserted on it from tumor fragments to therapeutic agents or various biomaterials. Five types of collagen-based biomaterials with 2D and 3D structure (MotifMesh, Optimaix2D, Optimaix3D, Dual Layer Collagen and Xenoderm) were implanted on CAM and continuously evaluated by stereomicroscope for up to 5 days post-implant with an emphasis of their ability to requisite and develop new blood vessels (BVs) followed by microscopic analysis. MotifMEsh did not induce any angiogenic response lacking to be invaded by BVs from the CAM, but it induced intense inflammatory response necrosis and fibroblastic reaction around the implant. Optimaix2D has good adherence. CAM with minimal or no inflammatory reaction, a good integration of the CAM between the collagen mesh’s fibers, consistent adhesion of the cells to the collagen fibers,and a good ability to form pseudo-vascular channels filled with cells. Optimaix3D induced the highest angiogenic effects on CAM. The material shows good integration on CAM. The collagen fibers of the material show the ability to organize themselves into linear and tubular structures. It is possible to see blood elements, especially at the periphery of the implant. Dual-layer collagen behaves similar to Optimaix 3D, while Xenoderm induced a moderate angiogenic effect on CAM. Based on these data, we may conclude that collagen-based materials have variable ability to requisite and develop new blood vessels. A proper selection of collagen-based biomaterial scaffolds may crucially influence the acquisition and development of blood vessels during angiogenesis assays.Keywords: chick embryo chorioallantoic membrane, collagen scaffolds, blood vessels, vascular microenvironment
Procedia PDF Downloads 1951920 Gender Difference and Conflict Management Strategy Preference among Managers in Public Organizations in South-Western Nigeria
Authors: D. I. Akintayo, C. O. Aje
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This study investigated the moderating influence of gender difference and conflict resolution strategy preference on managers` efficiency in managing industrial conflict in work organizations in South-Western Nigeria. This was for the purpose of ascertaining the relevance of gender difference and conflict resolution strategy preference to managerial efficiency towards ensuring sustainable industrial peace and harmonious labour-management relations at workplaces in Nigeria. Descriptive ex-post-facto research design was adopted for the study. A total of 185 respondents were selected for the study using purposive stratified sampling technique. A set of questionnaire titled ‘Rahim Organizational Conflict Inventory’ (ROCI) and Managerial Conflict Efficiency Scale (MCES) were adopted for the study. The three generated hypotheses were tested using Pearson Product Moment Correlation and t-test statistical methods. The findings of the study revealed that: A significant relationship exists between gender difference and conflict management preference of the managers(r = 0.644; P < 0.05). I t was also found that there was no significant difference between male and female managers’ conflict management strategy preference (t (181) = 11.08; P > 0.05).The finding reveals that there is no significant difference between female and male managers’ conflict management efficiency on the basis of conflict management preference of the managers (t (181) = 10.23; P > 0.05). Based on the findings of the study, it is recommended that collective bargaining strategy should be encouraged as conflict resolution strategy in order to guarantee effective management of industrial conflict and harmonious labour-management relations. Also, both male and female managers should be empowered to be appointed to managerial positions and should avoid the use of coercion, competition, aggressiveness and pro-task in the course of managing industrial conflict. Rather, persuasion, compromising, relational, lobbying and participatory approaches should be employed during collective bargaining process in order to foster effective management of conflict at workplaces.Keywords: conflict management, gender difference, managerial studies, public organization and managers, strategy preference
Procedia PDF Downloads 4611919 Influence of Degassing on the Curing Behaviour and Void Occurrence Properties of Epoxy / Anhydride Resin System
Authors: Latha Krishnan, Andrew Cobley
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Epoxy resin is most widely used as matrices for composites of aerospace, automotive and electronic applications due to its outstanding mechanical properties. These properties are chiefly predetermined by the chemical structure of the prepolymer and type of hardener but can also be varied by the processing conditions such as prepolymer and hardener mixing, degassing and curing conditions. In this research, the effect of degassing on the curing behaviour and the void occurrence is experimentally evaluated for epoxy /anhydride resin system. The epoxy prepolymer was mixed with an anhydride hardener and accelerator in an appropriate quantity. In order to investigate the effect of degassing on the curing behaviour and void content of the resin, the uncured resin samples were prepared using three different methods: 1) no degassing 2) degassing on prepolymer and 3) degassing on mixed solution of prepolymer and hardener with an accelerator. The uncured resins were tested in differential scanning calorimeter (DSC) to observe the changes in curing behaviour of the above three resin samples by analysing factors such as gel temperature, peak cure temperature and heat of reaction/heat flow in curing. Additionally, the completely cured samples were tested in DSC to identify the changes in the glass transition temperature (Tg) between the three samples. In order to evaluate the effect of degassing on the void content and morphology changes in the cured epoxy resin, the fractured surfaces of cured epoxy resin were examined under the scanning electron microscope (SEM). In addition, the amount of void, void geometry and void fraction were also investigated using an optical microscope and image J software (image analysis software). It was found that degassing at different stages of resin mixing had significant effects on properties such as glass transition temperature, the void content and void size of the epoxy/anhydride resin system. For example, degassing (vacuum applied on the mixed resin) has shown higher glass transition temperature (Tg) with lower void content.Keywords: anhydride epoxy, curing behaviour, degassing, void occurrence
Procedia PDF Downloads 2171918 Comparative Study on the Social Behaviour of Sambar Deer (Rusa unicolor) in Captive Facilities in Peninsular Malaysia
Authors: Kushaal Selvarajah, Geetha Annavi, Mohd Noor Hisham Mohd Nadzir
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Sambar deer (Rusa unicolor) was uplisted from Least Concern to Vulnerable by the International Union for Conservation of Nature Red list in 2015 due to drastic population decline in the wild throughout its geographical range. Sambar deer is a valued prey for the highly endangered species such as the Malayan tiger. Ex-situ conservation efforts, i.e., captive breeding, initiated by local government to boost sambar deer numbers in captivity and to reintroduce into the wild to support a higher number of tigers, consistent with the goal of our National Tiger Conservation Action Plan. The reproductive success of sambar deer and their welfare management practices in captivity are important components for effective captive breeding programs. However, there is a lack of study carried out on sambar deer in recent years and their behavior in captivity. Three captive sites (Zoo Negara, Zoo Taiping, and Sungkai Conservation Centre) were selected and observed for an average of 40 days each site (6 hours/day). A Generalized Linear Model (GLM) was used to determine the correlation between social behavior and extrinsic parameters. A comparison between all three captive sites showed the strongest correlation in behavioral variability, followed by a time of observation. This proves that there is a difference between in behavioral consistency and frequency between herds across captive sites rising to the possibility of external factors that are influential. Time of day of observation also had significant influence on certain extrinsic parameters being skewed to morning observations and this could be due to an adaptive behavior to the feeding time in the captive sites being in the morning which caused the deer to be resting towards the afternoon. Extensive study need to be done on sambar deer to pinpoint the specifics and better understanding of these possible influential factors in their behavior.Keywords: behaviour ecology, captivity, ex-situ conservation, husbandry
Procedia PDF Downloads 1591917 Using Hierarchical Modelling to Understand the Role of Plantations in the Abundance of Koalas, Phascolarctos cinereus
Authors: Kita R. Ashman, Anthony R. Rendall, Matthew R. E. Symonds, Desley A. Whisson
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Forest cover is decreasing globally, chiefly due to the conversion of forest to agricultural landscapes. In contrast, the area under plantation forestry is increasing significantly. For wildlife occupying landscapes where native forest is the dominant land cover, plantations generally represent a lower value habitat; however, plantations established on land formerly used for pasture may benefit wildlife by providing temporary forest habitat and increasing connectivity. This study investigates the influence of landscape, site, and climatic factors on koala population density in far south-west Victoria where there has been extensive plantation establishment. We conducted koala surveys and habitat characteristic assessments at 72 sites across three habitat types: plantation, native vegetation blocks, and native vegetation strips. We employed a hierarchical modeling framework for estimating abundance and constructed candidate multinomial N-mixture models to identify factors influencing the abundance of koalas. We detected higher mean koala density in plantation sites (0.85 per ha) than in either native block (0.68 per ha) or native strip sites (0.66 per ha). We found five covariates of koala density and using these variables, we spatially modeled koala abundance and discuss factors that are key in determining large-scale distribution and density of koala populations. We provide a distribution map that can be used to identify high priority areas for population management as well as the habitat of high conservation significance for koalas. This information facilitates the linkage of ecological theory with the on-ground implementation of management actions and may guide conservation planning and resource management actions to consider overall landscape configuration as well as the spatial arrangement of plantations adjacent to the remnant forest.Keywords: abundance modelling, arboreal mammals plantations, wildlife conservation
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