Search results for: multi- criteria evaluation method
Commenced in January 2007
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Paper Count: 27962

Search results for: multi- criteria evaluation method

662 The Psychological and Subjective Well-being of Ethiopian adults: Correlates, Explanations, and Cross-Cultural Constructions

Authors: Kassahun Tilahun

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The purpose of the study was two-fold: to examine the socio-demographic and psychological predictors of well-being and formulate a socio-culturally sound approach explaining the meaning and experience of psychological well-being among Ethiopian adults. Ryan and Deci’s Self-Determination Theory was duly considered as a theoretical framework of the study. The study followed a sequential explanatory mixed method design. Both quantitative and qualitative data were obtained, via scales and open-ended questionnaires, from 438 civil servants working in Addis Ababa. 30 interviews were also conducted to gain further information. An in-depth analysis of the reliability and validity of instruments was made before employing them to the main study. The results showed that adults were better off in both their scores of psychological and subjective well-being. Besides, adults’ well-being was found to be quite a function of their gender, age, marital status, educational level and household income. Males had a healthier psychological well-being status than females, where as females were better in their subjective well-being. A significant difference in psychological well-being was also observed between emerging and young adults, in favor of the young; and between cohabitated and married adults, married being advantageous. A significant difference in subjective well-being measures was also noticed among single, cohabitated and married adults, in favor of the married adults in all measures. The finding revealed that happiness level of adults decrease as their educational status increases while the reverse is true to psychological well-being. Besides, as adults’ household income boosts, so do their psychological well-being and satisfaction in life. The regression analysis also produced significant independent contributions of household income to overall well-being of adults. As such, subjective well-being was significantly predicted by dummy variable of sex and marital status. Likewise, the agreeableness, conscientiousness, neuroticism and openness dimensions of personality were notable significant predictors of adults’ psychological well-being where as extraversion and agreeableness were significant predictors of their subjective well-being. Religiosity was also a significant predictor of adults’ psychological well-being. Besides, adults’ well-being was significantly predicted by the interaction between conscientiousness and religiosity. From goal pursuit dimensions, attainment of extrinsic life goals was a significant predictor of both psychological and subjective well-being. Importance and attainment of intrinsic life goals also significantly predicts adults’ psychological well-being. Finally, the subjective well-being of adults was significantly predicted by environmental mastery, positive relations with others, self-acceptance and overall psychological well-being scores of adults. The thematic analysis identified five major categories of themes, which are essential in explaining the psychological well-being of Ethiopian adults. These were; socio-cultural harmony, social cohesion, security, competence and accomplishment, and the self. Detailed discussion on the rational for including these themes was made and appropriate implications were proposed. Researchers are encouraged to expand the findings of this research and in turn develop a suitable approach taping the psychological well-being of adults living in countries like Ethiopia.

Keywords: psychological well-being, subjective well-being, adulthood, Ethiopia

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661 Co-Designing Health as a Social Community Centre: The Case of a 'Doctors of the World Project' in Brussels

Authors: Marco Ranzato, Maguelone Vignes

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The co-design process recently run by the trans-disciplinary urban laboratory Metrolab Brussels for outlining the architecture of a future integrated health centre in Brussels (Belgium) has highlighted that a buffer place open to the local community is the appropriate cornerstone around which organizing a space where diverse professionals and patients are together. In the context of the migrants 'crisis' in Europe, the growing number of vulnerable people in Brussels and the increasing complexity of the health and welfare systems, the NGO Doctors of the World (DoW) has launched a project funded by The European Regional Development Fund, and aiming to create a new community centre combining social and health services in a poor but changing neighborhood of Brussels. Willing not to make a 'ghetto' of this new integrated service, the NGO looks at hosting different publics in order to make the poorest, marginal and most vulnerable people access to a regular kind of service. As a trans-disciplinary urban research group, Metrolab has been involved in the process of co-designing the architecture of the future centre with a set of various health professionals, social workers, and patients’ representatives. Metrolab drawn on the participants’ practice experiences and knowledge of hosting different kinds of publics and professions in a same structure in order to imagine what rooms should fit into the centre, what atmosphere they should convey, how should they be interrelated and organized, and, concurrently, how the building should fit into the urban frame of its neighborhood. The result is that, in order for an integrated health centre framed in the landscape of a disadvantaged neighborhood to function, it has to work as social community centre offering accessibility and conviviality to diverse social groups. This paper outlines the methodology that Metrolab used to design and conduct, in close collaboration with DoW, a series of 3 workshops. Through sketching and paper modeling, the methodology made participants talk about their experience by projecting them into a situation. It included a combination of individual and collective work in order to sharp participants’ eyes on architectural forms, explicit their thoughts and experience through inter-subjectivity and imagine solutions to the challenges they raised. Such a collaborative method encompasses several challenges about patients’ participation and representation, replicability of the conditions of success and the plurality of the research findings communication formats. This paper underlines how this participatory process has contributed to build knowledge on the few-documented topic of the architecture of community health centres. More importantly, the contribution builds on this participatory process to discuss the importance of adapting the architecture of the new integrated health centre to the changing population of Brussels and to the issues of its specific neighborhood.

Keywords: co-design, health, social innovation, urban lab

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660 Glycemic Control in Rice Consumption among Households with Diabetes Patients: The Role of Food Security

Authors: Chandanee Wasana Kalansooriya

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Dietary behaviour is a crucial factor affecting diabetes control. With increasing rates of diabetes prevalence in Asian countries, examining their dietary patterns, which are largely based on rice, is timely required. It has been identified that higher consumption of some rice varieties is associated with increased risk of type 2 diabetes. Although diabetes patients are advised to consume healthier rice varieties, which contains low glycemic, several conditions, one of which food insecurity, make them difficult to preserve those healthy dietary guidelines. Hence this study tries to investigate how food security affects on making right decisions of rice consumption within diabetes affected households using a sample from Sri Lanka, a country which rice considered as the staple food and records the highest diabetes prevalence rate in South Asia. The study uses data from the Household Income and Expenditure Survey 2016, a nationally representative sample conducted by the Department of Census and Statistics, Sri Lanka. The survey used a two-stage stratified sampling method to cover different sectors and districts of the country and collected micro-data on demographics, health, income and expenditures of different categories. The study uses data from 2547 households which consist of one or more diabetes patients, based on the self-recorded health status. The Household Dietary Diversity Score (HDDS), which constructed based on twelve food groups, is used to measure the level of food security. Rice is categorized into three groups according to their Glycemic Index (GI), high GI, medium GI and low GI, and the likelihood and impact made by food security on each rice consumption categories are estimated using a Two-part Model. The shares of each rice categories out of total rice consumption is considered as the dependent variable to exclude the endogeneity issue between rice consumption and the HDDS. The results indicate that the consumption of medium GI rice is likely to increase with the increasing household food security, but low GI varieties are not. Households in rural and estate sectors are less likely and Tamil ethnic group is more likely to consume low GI rice varieties. Further, an increase in food security significantly decreases the consumption share of low GI rice, while it increases the share of medium GI varieties. The consumption share of low GI rice is largely affected by the ethnic variability. The effects of food security on the likelihood of consuming high GI rice varieties and changing its shares are statistically insignificant. Accordingly, the study concludes that a higher level of food security does not ensure diabetes patients are consuming healthy rice varieties or reducing consumption of unhealthy varieties. Hence policy attention must be directed towards educating people for making healthy dietary choices. Further, the study provides a room for further studies as it reveals considerable ethnic and sectorial differences in making healthy dietary decisions.

Keywords: diabetes, food security, glycemic index, rice consumption

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659 Studies of the Reaction Products Resulted from Glycerol Electrochemical Conversion under Galvanostatic Mode

Authors: Ching Shya Lee, Mohamed Kheireddine Aroua, Wan Mohd Ashri Wan Daud, Patrick Cognet, Yolande Peres, Mohammed Ajeel

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In recent years, with the decreasing supply of fossil fuel, renewable energy has received a significant demand. Biodiesel which is well known as vegetable oil based fatty acid methyl ester is an alternative fuel for diesel. It can be produced from transesterification of vegetable oils, such as palm oil, sunflower oil, rapeseed oil, etc., with methanol. During the transesterification process, crude glycerol is formed as a by-product, resulting in 10% wt of the total biodiesel production. To date, due to the fast growing of biodiesel production in worldwide, the crude glycerol supply has also increased rapidly and resulted in a significant price drop for glycerol. Therefore, extensive research has been developed to use glycerol as feedstock to produce various added-value chemicals, such as tartronic acid, mesoxalic acid, glycolic acid, glyceric acid, propanediol, acrolein etc. The industrial processes that usually involved are selective oxidation, biofermentation, esterification, and hydrolysis. However, the conversion of glycerol into added-value compounds by electrochemical approach is rarely discussed. Currently, the approach is mainly focused on the electro-oxidation study of glycerol under potentiostatic mode for cogenerating energy with other chemicals. The electro-organic synthesis study from glycerol under galvanostatic mode is seldom reviewed. In this study, the glycerol was converted into various added-value compounds by electrochemical method under galvanostatic mode. This work aimed to study the possible compounds produced from glycerol by electrochemical technique in a one-pot electrolysis cell. The electro-organic synthesis study from glycerol was carried out in a single compartment reactor for 8 hours, over the platinum cathode and anode electrodes under acidic condition. Various parameters such as electric current (1.0 A to 3.0 A) and reaction temperature (27 °C to 80 °C) were evaluated. The products obtained were characterized by using gas chromatography-mass spectroscopy equipped with an aqueous-stable polyethylene glycol stationary phase column. Under the optimized reaction condition, the glycerol conversion achieved as high as 95%. The glycerol was successfully converted into various added-value chemicals such as ethylene glycol, glycolic acid, glyceric acid, acetaldehyde, formic acid, and glyceraldehyde; given the yield of 1%, 45%, 27%, 4%, 0.7% and 5%, respectively. Based on the products obtained from this study, the reaction mechanism of this process is proposed. In conclusion, this study has successfully converted glycerol into a wide variety of added-value compounds. These chemicals are found to have high market value; they can be used in the pharmaceutical, food and cosmetic industries. This study effectively opens a new approach for the electrochemical conversion of glycerol. For further enhancement on the product selectivity, electrode material is an important parameter to be considered.

Keywords: biodiesel, glycerol, electrochemical conversion, galvanostatic mode

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658 Highly Conducting Ultra Nanocrystalline Diamond Nanowires Decorated ZnO Nanorods for Long Life Electronic Display and Photo-Detectors Applications

Authors: A. Saravanan, B. R. Huang, C. J. Yeh, K. C. Leou, I. N. Lin

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A new class of ultra-nano diamond-graphite nano-hybrid (DGH) composite materials containing nano-sized diamond needles was developed at low temperature process. Such kind of diamond- graphite nano-hybrid composite nanowires exhibit high electrical conductivity and excellent electron field emission (EFE) properties. Few earlier reports mention that addition of N2 gas to the growth plasma requires high growth temperature (800°C) to trigger the dopants to generate the conductivity in the films. High growth temperature is not familiar with the Si-based device fabrications. We have used a novel process such as bias-enhanced-grown (beg) MPECVD process to grow diamond films at low substrate temperature (450°C). We observed that the beg-N/UNCD films thus obtained possess high conductivity of σ=987 S/cm, ever reported for diamond films with excellent Electron field emission (EFE) properties. TEM investigation indicated that these films contain needle-like diamond grains about 5 nm in diameter and hundreds of nanometers in length. Each of the grains was encased in graphitic layers about tens of nano-meters in thickness. These materials properties suitable for more specific applications, such as high conductivity for electron field emitters, high robustness for microplasma cathodes and high electrochemical activity for electro-chemical sensing. Subsequently, other hand, the highly conducting DGH films were coated on vertically aligned ZnO nanorods, there is no prior nucleation or seeding process needed due to the use of BEG method. Such a composite structure provides significant enhancement in the field emission characteristics of the cold cathode was observed with ultralow turn on voltage 1.78 V/μm with high EFE current density of 3.68 mA/ cm2 (at 4.06V/μm) due to decoration of DGH material on ZnO nanorods. The DGH/ZNRs based device get stable emission for longer duration of 562min than bare ZNRs (104min) without any current degradation because the diamond coating protects the ZNRs from ion bombardment when they are used as the cathode for microplasma devices. The potential application of these materials is demonstrated by the plasma illumination measurements that ignited the plasma at the minimum voltage by 290 V. The photoresponse (Iphoto/Idark) behavior of the DGH/ZNRs based photodetectors exhibits a much higher photoresponse (1202) than bare ZNRs (229). During the process the electron transport is easy from ZNRs to DGH through graphitic layers, the EFE properties of these materials comparable to other primarily used field emitters like carbon nanotubes, graphene. The DGH/ZNRs composite also providing a possibility of their use in flat panel, microplasma and vacuum microelectronic devices.

Keywords: bias-enhanced nucleation and growth, ZnO nanorods, electrical conductivity, electron field emission, photo-detectors

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657 Listening to Voices: A Meaning-Focused Framework for Supporting People with Auditory Verbal Hallucinations

Authors: Amar Ghelani

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People with auditory verbal hallucinations (AVH) who seek support from mental health services commonly report feeling unheard and invalidated in their interactions with social workers and psychiatric professionals. Current mental health training and clinical approaches have proven to be inadequate in addressing the complex nature of voice hearing. Childhood trauma is a key factor in the development of AVH and can render people more vulnerable to hearing both supportive and/or disturbing voices. Lived experiences of racism, poverty, and immigration are also associated with development of what is broadly classified as psychosis. Despite evidence affirming the influence of environmental factors on voice hearing, the Western biomedical system typically conceptualizes this experience as a symptom of genetically-based mental illnesses which requires diagnosis and treatment. Overemphasis on psychiatric medications, referrals, and directive approaches to people’s problems has shifted clinical interventions away from assessing and addressing problems directly related to AVH. The Maastricht approach offers voice hearers and mental health workers an alternative and respectful starting point for understanding and coping with voices. The approach was developed by voice hearers in partnership with mental health professionals and entails an innovative method to assess and create meaning from voice hearing and related life stressors. The objectives of the approach are to help people who hear voices: (1) understand the problems and/or people the voices may represent in their history, and (2) cope with distress and find solutions to related problems. The Maastricht approach has also been found to help voice hearers integrate emotional conflicts, reduce avoidance or fear associated with AVH, improve therapeutic relationships, and increase a sense of control over internal experiences. The proposed oral presentation will be guided by a recovery-oriented theoretical framework which suggests healing from psychological wounds occurs through social connections and community support systems. The presentation will start with a brainstorming exercise to identify participants pre-existing knowledge of the subject matter. This will lead into a literature review on the relations between trauma, intersectionality, and AVH. An overview of the Maastricht approach and review of research related to its therapeutic risks and benefits will follow. Participants will learn trauma-informed coping skills and questions which can help voice hearers make meaning from their experiences. The presentation will conclude with a review of resources and learning opportunities where participants can expand their knowledge of the Hearing Voices Movement and Maastricht approach.

Keywords: Maastricht interview, recovery, therapeutic assessment, voice hearing

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656 Analysis of the Outcome of the Treatment of Osteoradionecrosis in Patients after Radiotherapy for Head and Neck Cancer

Authors: Petr Daniel Kovarik, Matt Kennedy, James Adams, Ajay Wilson, Andy Burns, Charles Kelly, Malcolm Jackson, Rahul Patil, Shahid Iqbal

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Introduction: Osteoradionecrosis (ORN) is a recognised toxicity of radiotherapy (RT) for head and neck cancer (HNC). Existing literature lacks any generally accepted definition and staging system for this toxicity. Objective: The objective is to analyse the outcome of the surgical and nonsurgical treatments of ORN. Material and Method: Data on 2303 patients treated for HNC with radical or adjuvant RT or RT-chemotherapy from January 2010 - December 2021 were retrospectively analysed. Median follow-up to the whole group of patients was 37 months (range 0–148 months). Results: ORN developed in 185 patients (8.1%). The location of ORN was as follows; mandible=170, maxilla=10, and extra oral cavity=5. Multiple ORNs developed in 7 patients. 5 patients with extra oral cavity ORN were excluded from treatment analysis as the management is different. In 180 patients with oral cavity ORN, median follow-up was 59 months (range 5–148 months). ORN healed in 106 patients, treatment failed in 74 patients (improving=10, stable=43, and deteriorating=21). Median healing time was 14 months (range 3-86 months). Notani staging is available in 158 patients with jaw ORN with no previous surgery to the mandible (Notani class I=56, Notani class II=27, and Notani class III=76). 28 ORN (mandible=27, maxilla=1; Notani class I=23, Notani II=3, Notani III=1) healed spontaneously with a median healing time 7 months (range 3–46 months). In 20 patients, ORN developed after dental extraction, in 1 patient in the neomandible after radical surgery as a part of the primary treatment. In 7 patients, ORN developed and spontaneously healed in irradiated bone with no previous surgical/dental intervention. Radical resection of the ORN (segmentectomy, hemi-mandibulectomy with fibula flap) was performed in 43 patients (all mandible; Notani II=1, Notani III=39, Notani class was not established in 3 patients as ORN developed in the neomandible). 27 patients healed (63%); 15 patients failed (improving=2, stable=5, deteriorating=8). The median time from resection to healing was 6 months (range 2–30 months). 109 patients (mandible=100, maxilla=9; Notani I=3, Notani II=23, Notani III=35, Notani class was not established in 9 patients as ORN developed in the maxilla/neomandible) were treated conservatively using a combination of debridement, antibiotics and Pentoclo. 50 patients healed (46%) with a median healing time 14 months (range 3–70 months), 59 patients are recorded with persistent ORN (improving=8, stable=38, deteriorating=13). Out of 109 patients treated conservatively, 13 patients were treated with Pentoclo only (all mandible; Notani I=6, Notani II=3, Notani III=3, 1 patient with neomandible). In total, 8 patients healed (61.5%), treatment failed in 5 patients (stable=4, deteriorating=1). Median healing time was 14 months (range 4–24 months). Extra orally (n=5), 3 cases of ORN were in the auditory canal and 2 in mastoid. ORN healed in one patient (auditory canal after 32 months. Treatment failed in 4 patients (improving=3, stable=1). Conclusion: The outcome of the treatment of ORN remains in general, poor. Every effort should therefore be made to minimise the risk of development of this devastating toxicity.

Keywords: head and neck cancer, radiotherapy, osteoradionecrosis, treatment outcome

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655 Advancing Equitable Healthcare for Trans and Gender-Diverse Students: A Community-Based Participatory Action Project

Authors: Al Huuskonen, Clio Lake, K. M. Naude, Polina Petlitsyna, Sorsha Henning, Julia Wimmers-Klick

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This project presents the outcomes of a community-based participatory action initiative aimed at advocating for equitable healthcare and human rights for trans, two-spirit, and gender-diverse individuals, building upon the University of British Columbia (UBC) Trans Coalition's ongoing efforts. Participatory Action Research (PAR) was chosen as the research method with the goal of improving trans rights on the UBC campus, particularly regarding equitable access to healthcare. PAR involves active community contribution throughout the research process, which in this case was done by way of liaising with student resource groups and advocacy leaders. The goals of this project were as follows: a) identify gaps in gender-affirming healthcare for UBC students by consulting the community and collaborating with UBC services, b) develop an information package outlining provincial and university-based health insurance for gender-affirming care (including hormone therapy and surgeries), FAQs, and resources for UBC's trans students, c) make this package available to UBC students and other national transgender advocacy organizations. The initiative successfully expanded the UBC AMS Student Health and Dental Plan to include gender-affirming procedural coverage, developed a care access guide for students, and advocated for improved health records inclusivity, mechanisms for trans students to report negative care experiences, and increased access to gender-affirming primary care through the on-campus health clinic. Collaboration with other universities' pride organizations and Trans Care BC yielded positive outcomes through broader coalition building and resource sharing. Ongoing efforts are underway to update provincial policies, particularly through expanding coverage under fair pharma care and addressing the compounding effects of the primary care crisis for trans individuals. The project's tangible results include improved trans rights on campus, especially in terms of healthcare access. Expanding healthcare coverage through student care benefits thousands of students, making the ability to undergo important affirming procedures more affordable. Providing students with information on extended coverage options and communication with their doctors further removes barriers to care and positively impacts student wellbeing. This initiative demonstrates the effectiveness of community-based participatory action in advancing equitable healthcare for trans and gender-diverse individuals and serves as a model for other institutions and organizations striving to promote inclusivity and advocate for marginalized populations' rights.

Keywords: equitable healthcare, trans and gender-diverse individuals, inclusivity, participatory action research project

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654 Empowering South African Female Farmers through Organic Lamb Production: A Cost Analysis Case Study

Authors: J. M. Geyser

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Lamb is a popular meat throughout the world, particularly in Europe, the Middle East and Oceania. However, the conventional lamb industry faces challenges related to environmental sustainability, climate change, consumer health and dwindling profit margins. This has stimulated an increasing demand for organic lamb, as it is perceived to increase environmental sustainability, offer superior quality, taste, and nutritional value, which is appealing to farmers, including small-scale and female farmers, as it often commands a premium price. Despite its advantages, organic lamb production presents challenges, with a significant hurdle being the high production costs encompassing organic certification, lower stocking rates, higher mortality rates and marketing cost. These costs impact the profitability and competitiveness or organic lamb producers, particularly female and small-scale farmers, who often encounter additional obstacles, such as limited access to resources and markets. Therefore, this paper examines the cost of producing organic lambs and its impact on female farmers and raises the research question: “Is organic lamb production the saving grace for female and small-scale farmers?” Objectives include estimating and comparing production costs and profitability or organic lamb production with conventional lamb production, analyzing influencing factors, and assessing opportunities and challenges for female and small-scale farmers. The hypothesis states that organic lamb production can be a viable and beneficial option for female and small-scale farmers, provided that they can overcome high production costs and access premium markets. The study uses a mixed-method approach, combining qualitative and quantitative data. Qualitative data involves semi-structured interviews with ten female and small-scale farmers engaged in organic lamb production in South Africa. The interview covered topics such as farm characteristics, practices, cost components, mortality rates, income sources and empowerment indicators. Quantitative data used secondary published information and primary data from a female farmer. The research findings indicate that when a female farmer moves from conventional lamb production to organic lamb production, the cost in the first year of organic lamb production exceed those of conventional lamb production by over 100%. This is due to lower stocking rates and higher mortality rates in the organic system. However, costs start decreasing in the second year as stocking rates increase due to manure applications on grazing and lower mortality rates due to better worm resistance in the herd. In conclusion, this article sheds light on the economic dynamics of organic lamb production, particularly focusing on its impact on female farmers. To empower female farmers and to promote sustainable agricultural practices, it is imperative to understand the cost structures and profitability of organic lamb production.

Keywords: cost analysis, empowerment, female farmers, organic lamb production

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653 Knowledge Creation Environment in the Iranian Universities: A Case Study

Authors: Mahdi Shaghaghi, Amir Ghaebi, Fariba Ahmadi

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Purpose: The main purpose of the present research is to analyze the knowledge creation environment at a Iranian University (Alzahra University) as a typical University in Iran, using a combination of the i-System and Ba models. This study is necessary for understanding the determinants of knowledge creation at Alzahra University as a typical University in Iran. Methodology: To carry out the present research, which is an applied study in terms of purpose, a descriptive survey method was used. In this study, a combination of the i-System and Ba models has been used to analyze the knowledge creation environment at Alzahra University. i-System consists of 5 constructs including intervention (input), intelligence (process), involvement (process), imagination (process), and integration (output). The Ba environment has three pillars, namely the infrastructure, the agent, and the information. The integration of these two models resulted in 11 constructs which were as follows: intervention (input), infrastructure-intelligence, agent-intelligence, information-intelligence (process); infrastructure-involvement, agent-involvement, information-involvement (process); infrastructure-imagination, agent-imagination, information-imagination (process); and integration (output). These 11 constructs were incorporated into a 52-statement questionnaire and the validity and reliability of the questionnaire were examined and confirmed. The statistical population included the faculty members of Alzahra University (344 people). A total of 181 participants were selected through the stratified random sampling technique. The descriptive statistics, binomial test, regression analysis, and structural equation modeling (SEM) methods were also utilized to analyze the data. Findings: The research findings indicated that among the 11 research constructs, the levels of intervention, information-intelligence, infrastructure-involvement, and agent-imagination constructs were average and not acceptable. The levels of infrastructure-intelligence and information-imagination constructs ranged from average to low. The levels of agent-intelligence and information-involvement constructs were also completely average. The level of infrastructure-imagination construct was average to high and thus was considered acceptable. The levels of agent-involvement and integration constructs were above average and were in a highly acceptable condition. Furthermore, the regression analysis results indicated that only two constructs, viz. the information-imagination and agent-involvement constructs, positively and significantly correlate with the integration construct. The results of the structural equation modeling also revealed that the intervention, intelligence, and involvement constructs are related to the integration construct with the complete mediation of imagination. Discussion and conclusion: The present research suggests that knowledge creation at Alzahra University relatively complies with the combination of the i-System and Ba models. Unlike this model, the intervention, intelligence, and involvement constructs are not directly related to the integration construct and this seems to have three implications: 1) the information sources are not frequently used to assess and identify the research biases; 2) problem finding is probably of less concern at the end of studies and at the time of assessment and validation; 3) the involvement of others has a smaller role in the summarization, assessment, and validation of the research.

Keywords: i-System, Ba model , knowledge creation , knowledge management, knowledge creation environment, Iranian Universities

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652 Gender Gap in Returns to Social Entrepreneurship

Authors: Saul Estrin, Ute Stephan, Suncica Vujic

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Background and research question: Gender differences in pay are present at all organisational levels, including at the very top. One possible way for women to circumvent organizational norms and discrimination is to engage in entrepreneurship because, as CEOs of their own organizations, entrepreneurs largely determine their own pay. While commercial entrepreneurship plays an important role in job creation and economic growth, social entrepreneurship has come to prominence because of its promise of addressing societal challenges such as poverty, social exclusion, or environmental degradation through market-based rather than state-sponsored activities. This opens the research question whether social entrepreneurship might be a form of entrepreneurship in which the pay of men and women is the same, or at least more similar; that is to say there is little or no gender pay gap. If the gender gap in pay persists also at the top of social enterprises, what are the factors, which might explain these differences? Methodology: The Oaxaca-Blinder Decomposition (OBD) is the standard approach of decomposing the gender pay gap based on the linear regression model. The OBD divides the gender pay gap into the ‘explained’ part due to differences in labour market characteristics (education, work experience, tenure, etc.), and the ‘unexplained’ part due to differences in the returns to those characteristics. The latter part is often interpreted as ‘discrimination’. There are two issues with this approach. (i) In many countries there is a notable convergence in labour market characteristics across genders; hence the OBD method is no longer revealing, since the largest portion of the gap remains ‘unexplained’. (ii) Adding covariates to a base model sequentially either to test a particular coefficient’s ‘robustness’ or to account for the ‘effects’ on this coefficient of adding covariates might be problematic, due to sequence-sensitivity when added covariates are correlated. Gelbach’s decomposition (GD) addresses latter by using the omitted variables bias formula, which constructs a conditional decomposition thus accounting for sequence-sensitivity when added covariates are correlated. We use GD to decompose the differences in gaps of pay (annual and hourly salary), size of the organisation (revenues), effort (weekly hours of work), and sources of finances (fees and sales, grants and donations, microfinance and loans, and investors’ capital) between men and women leading social enterprises. Database: Our empirical work is made possible by our collection of a unique dataset using respondent driven sampling (RDS) methods to address the problem that there is as yet no information on the underlying population of social entrepreneurs. The countries that we focus on are the United Kingdom, Spain, Romania and Hungary. Findings and recommendations: We confirm the existence of a gender pay gap between men and women leading social enterprises. This gap can be explained by differences in the accumulation of human capital, psychological and social factors, as well as cross-country differences. The results of this study contribute to a more rounded perspective, highlighting that although social entrepreneurship may be a highly satisfying occupation, it also perpetuates gender pay inequalities.

Keywords: Gelbach’s decomposition, gender gap, returns to social entrepreneurship, values and preferences

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651 Enhancing of Antibacterial Activity of Essential Oil by Rotating Magnetic Field

Authors: Tomasz Borowski, Dawid Sołoducha, Agata Markowska-Szczupak, Aneta Wesołowska, Marian Kordas, Rafał Rakoczy

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Essential oils (EOs) are fragrant volatile oils obtained from plants. These are used for cooking (for flavor and aroma), cleaning, beauty (e.g., rosemary essential oil is used to promote hair growth), health (e.g. thyme essential oil cures arthritis, normalizes blood pressure, reduces stress on the heart, cures chest infection and cough) and in the food industry as preservatives and antioxidants. Rosemary and thyme essential oils are considered the most eminent herbs based on their history and medicinal properties. They possess a wide range of activity against different types of bacteria and fungi compared with the other oils in both in vitro and in vivo studies. However, traditional uses of EOs are limited due to rosemary and thyme oils in high concentrations can be toxic. In light of the accessible data, the following hypothesis was put forward: Low frequency rotating magnetic field (RMF) increases the antimicrobial potential of EOs. The aim of this work was to investigate the antimicrobial activity of commercial Salvia Rosmarinus L. and Thymus vulgaris L. essential oil from Polish company Avicenna-Oil under Rotating Magnetic Field (RMF) at f = 25 Hz. The self-constructed reactor (MAP) was applied for this study. The chemical composition of oils was determined by gas chromatography coupled with mass spectrometry (GC-MS). Model bacteria Escherichia coli K12 (ATCC 25922) was used. Minimum inhibitory concentrations (MIC) against E. coli were determined for the essential oils. Tested oils in very small concentrations were prepared (from 1 to 3 drops of essential oils per 3 mL working suspensions). From the results of disc diffusion assay and MIC tests, it can be concluded that thyme oil had the highest antibacterial activity against E. coli. Moreover, the study indicates the exposition to the RMF, as compared to the unexposed controls causing an increase in the efficacy of antibacterial properties of tested oils. The extended radiation exposure to RMF at the frequency f= 25 Hz beyond 160 minutes resulted in a significant increase in antibacterial potential against E. coli. Bacteria were killed within 40 minutes in thyme oil in lower tested concentration (1 drop of essential oils per 3 mL working suspension). Rapid decrease (>3 log) of bacteria number was observed with rosemary oil within 100 minutes (in concentration 3 drops of essential oils per 3 mL working suspension). Thus, a method for improving the antimicrobial performance of essential oil in low concentrations was developed. However, it still remains to be investigated how bacteria get killed by the EOs treated by an electromagnetic field. The possible mechanisms relies on alteration in the permeability of ionic channels in ionic channels in the bacterial cell walls that transport in the cells was proposed. For further studies, it is proposed to examine other types of essential oils and other antibiotic-resistant bacteria (ARB), which are causing a serious concern throughout the world.

Keywords: rotating magnetic field, rosemary, thyme, essential oils, Escherichia coli

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650 Stability in Slopes Related to Expansive Soils

Authors: Ivelise M. Strozberg, Lucas O. Vale, Maria V. V. Morais

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Expansive soils are characterized by their significant volumetric variations, tending to suffer an increase of this volume when added water in their voids and a decrease of volume when this water is removed. The parameters of resistance (especially the angle of friction, cohesion and specific weight) of expansive or non-expansive soils of the same field present differences, as found in laboratory tests. What is expected is that, through this research, demonstrate that this variation directly affects the results of the calculation of factors of safety for slope stability. The expansibility due to specific clay minerals such as montmorillonites and vermiculites is the most common form of expansion of soils or rocks, causing expansion pressures. These pressures can become an aggravating problem in regions across the globe that, when not previously studied, may present high risks to the enterprise, such as cracks, fissures, movements in structures, breaking of retaining walls, drilling of wells, among others. The study provides results based on analyzes carried out in the Slide 2018 software belonging to the Rocsience group, where the software is a two-dimensional equilibrium slope stability program that calculates the factor of safety or probability of failure of certain surfaces composed of soils or rocks (or both, depending on the situation), - through the methods of: Bishop simplified, Fellenius and Janbu corrected. This research compares the factors of safety of a homogeneous earthfill dam geometry, analysed for operation and end-of-construction situations, having a height of approximately 35 meters, with a slope of 1.5: 1 in the slope downstream and 2: 1 on the upstream slope. As the water level is 32.73m high and the water table is drawn automatically by the Slide program using the finite element method for the operating situation, considering two hypotheses for the use of materials - the first with soils with characteristics of expansion and the second with soils without expansibility. For this purpose, soil samples were collected from the region of São Bento do Una - Pernambuco, Brazil and taken to the soil mechanics laboratory to characterize and determine the percentage of expansibility. There were found 2 types of soils in that area: 1 site of expansive soils (8%) and another with non- expansive ones. Based on the results found, the analysis of the values of factors of safety indicated, both upstream and downstream slopes, the highest values were obtained in the case where there is no presence of materials with expansibility resulting, for one of the situations, values of 1.353 (Fellenius), 1,295 (Janbu corrected) and 1,409 (Bishop simplified). There is a considerable drop in safety factors in cases where soils are potentially expansive, resulting in values for the same situation of 0.859 (Fellenius), 0.809 (Janbu corrected) and 0.842 (Bishop simplified), in the case of higher expansibility (8 %). This shows that the expansibility is a determinant factor in the fall of resistance of soil, determined by the factors of cohesion and angle of friction.

Keywords: dam. slope. software. swelling soil

Procedia PDF Downloads 122
649 Zeolite 4A-confined Ni-Co Nanocluster: An Efficient and Durable Electrocatalyst for Alkaline Methanol Oxidation Reaction

Authors: Sarmistha Baruah, Akshai Kumar, Nageswara Rao Peela

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The global energy crisis due to the dependence on fossil fuels and its limited reserves as well as environmental pollution are key concerns to the research communities. However, the implementation of alcohol-based fuel cells such as methanol is anticipated as a reliable source of future energy technology due to their high energy density, environment friendliness, ease of storage, transportation, etc. To drive the anodic methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs), an active and long-lasting catalyst is necessary for efficient energy conversion from methanol. Recently, transition metal-zeolite-based materials have been considered versatile catalysts for a variety of industrial and lab-scale processes. Large specific surface area, well-organized micropores, and adjustable acidity/basicity are characteristics of zeolites that make them excellent supports for immobilizing small-sized and highly dispersed metal species. Significant advancement in the production and characterization of well-defined metal clusters encapsulated within zeolite matrix has substantially expanded the library of materials available, and consequently, their catalytic efficacy. In this context, we developed bimetallic Ni-Co catalysts encapsulated within LTA (also known as 4A) zeolite via a method combined with the in-situ encapsulation of metal species using hydrothermal treatment followed by a chemical reduction process. The prepared catalyst was characterized using advanced characterization techniques, such as X-ray diffraction (XRD), field emission transmission electron microscope (FETEM), field emission scanning electron microscope (FESEM), energy dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS). The electrocatalytic activity of the catalyst for MOR was carried out in an alkaline medium at room temperature using techniques such as cyclic voltammetry (CV), and chronoamperometry (CA). The resulting catalyst exhibited better catalytic activity of 12.1 mA cm-2 at 1.12 V vs Ag/AgCl and retained remarkable stability (~77%) even after 1000 cycles CV test for the electro-oxidation of methanol in alkaline media without any significant microstructural changes. The high surface area, better Ni-Co species integration in the zeolite, and the ample amount of surface hydroxyl groups contribute to highly dispersed active sites and quick analyte diffusion, which provide notable MOR kinetics. Thus, this study will open up new possibilities to develop a noble metal-free zeolite-based electrocatalyst due to its simple synthesis steps, large-scale fabrication, improved stability, and efficient activity for DMFC application.

Keywords: alkaline media, bimetallic, encapsulation, methanol oxidation reaction, LTA zeolite.

Procedia PDF Downloads 65
648 Accidental U.S. Taxpayers Residing Abroad: Choosing between U.S. Citizenship or Keeping Their Local Investment Accounts

Authors: Marco Sewald

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Due to the current enforcement of exterritorial U.S. legislation, up to 9 million U.S. (dual) citizens residing abroad are subject to U.S. double and surcharge taxation and at risk of losing access to otherwise basic financial services and investment opportunities abroad. The United States is the only OECD country that taxes non-resident citizens, lawful permanent residents and other non-resident aliens on their worldwide income, based on local U.S. tax laws. To enforce these policies the U.S. has implemented ‘saving clauses’ in all tax treaties and implemented several compliance provisions, including the Foreign Account Tax Compliance Act (FATCA), Qualified Intermediaries Agreements (QI) and Intergovernmental Agreements (IGA) addressing Foreign Financial Institutions (FFIs) to implement these provisions in foreign jurisdictions. This policy creates systematic cases of double and surcharge taxation. The increased enforcement of compliance rules is creating additional report burdens for U.S. persons abroad and FFIs accepting such U.S. persons as customers. FFIs in Europe react with a growing denial of specific financial services to this population. The numbers of U.S. citizens renouncing has dramatically increased in the last years. A case study is chosen as an appropriate methodology and research method, as being an empirical inquiry that investigates a contemporary phenomenon within its real-life context; when the boundaries between phenomenon and context are not clearly evident; and in which multiple sources of evidence are used. This evaluative approach is testing whether the combination of policies works in practice, or whether they are in accordance with desirable moral, political, economical aims, or may serve other causes. The research critically evaluates the financial and non-financial consequences and develops sufficient strategies. It further discusses these strategies to avoid the undesired consequences of exterritorial U.S. legislation. Three possible strategies are resulting from the use cases: (1) Duck and cover, (2) Pay U.S. double/surcharge taxes, tax preparing fees and accept imposed product limitations and (3) Renounce U.S. citizenship and pay possible exit taxes, tax preparing fees and the requested $2,350 fee to renounce. While the first strategy is unlawful and therefore unsuitable, the second strategy is only suitable if the U.S. citizen residing abroad is planning to move to the U.S. in the future. The last strategy is the only reasonable and lawful way provided by the U.S. to limit the exposure to U.S. double and surcharge taxation and the limitations on financial products. The results are believed to add a perspective to the current academic discourse regarding U.S. citizenship based taxation, currently dominated by U.S. scholars, while providing sufficient strategies for the affected population at the same time.

Keywords: citizenship based taxation, FATCA, FBAR, qualified intermediaries agreements, renounce U.S. citizenship

Procedia PDF Downloads 201
647 Treatment of Onshore Petroleum Drill Cuttings via Soil Washing Process: Characterization and Optimal Conditions

Authors: T. Poyai, P. Painmanakul, N. Chawaloesphonsiya, P. Dhanasin, C. Getwech, P. Wattana

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Drilling is a key activity in oil and gas exploration and production. Drilling always requires the use of drilling mud for lubricating the drill bit and controlling the subsurface pressure. As drilling proceeds, a considerable amount of cuttings or rock fragments is generated. In general, water or Water Based Mud (WBM) serves as drilling fluid for the top hole section. The cuttings generated from this section is non-hazardous and normally applied as fill materials. On the other hand, drilling the bottom hole to reservoir section uses Synthetic Based Mud (SBM) of which synthetic oils are composed. The bottom-hole cuttings, SBM cuttings, is regarded as a hazardous waste, in accordance with the government regulations, due to the presence of hydrocarbons. Currently, the SBM cuttings are disposed of as an alternative fuel and raw material in cement kiln. Instead of burning, this work aims to propose an alternative for drill cuttings management under two ultimate goals: (1) reduction of hazardous waste volume; and (2) making use of the cleaned cuttings. Soil washing was selected as the major treatment process. The physiochemical properties of drill cuttings were analyzed, such as size fraction, pH, moisture content, and hydrocarbons. The particle size of cuttings was analyzed via light scattering method. Oil present in cuttings was quantified in terms of total petroleum hydrocarbon (TPH) through gas chromatography equipped with flame ionization detector (GC-FID). Other components were measured by the standard methods for soil analysis. Effects of different washing agents, liquid-to-solid (L/S) ratio, washing time, mixing speed, rinse-to-solid (R/S) ratio, and rinsing time were also evaluated. It was found that drill cuttings held the electrical conductivity of 3.84 dS/m, pH of 9.1, and moisture content of 7.5%. The TPH in cuttings existed in the diesel range with the concentration ranging from 20,000 to 30,000 mg/kg dry cuttings. A majority of cuttings particles held a mean diameter of 50 µm, which represented silt fraction. The results also suggested that a green solvent was considered most promising for cuttings treatment regarding occupational health, safety, and environmental benefits. The optimal washing conditions were obtained at L/S of 5, washing time of 15 min, mixing speed of 60 rpm, R/S of 10, and rinsing time of 1 min. After washing process, three fractions including clean cuttings, spent solvent, and wastewater were considered and provided with recommendations. The residual TPH less than 5,000 mg/kg was detected in clean cuttings. The treated cuttings can be then used for various purposes. The spent solvent held the calorific value of higher than 3,000 cal/g, which can be used as an alternative fuel. Otherwise, the recovery of the used solvent can be conducted using distillation or chromatography techniques. Finally, the generated wastewater can be combined with the produced water and simultaneously managed by re-injection into the reservoir.

Keywords: drill cuttings, green solvent, soil washing, total petroleum hydrocarbon (TPH)

Procedia PDF Downloads 155
646 The Impact Of Türki̇ye’s Decision-making Mechanism On The Transformation In Türkiye-syria Relations (2002-2024)

Authors: Ibrahim Akkan

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This study analyses the transformation of Türkiye's Syria policy between 2002 and 2024 and the impact of domestic political dynamics in this process. Since the collapse of the Ottoman Empire, Türkiye and Syria have had a tense relationship for a long time due to reasons such as border issues, water sharing, security concerns and the activities of terrorist organizations. However, the process that started with the Adana Agreement in 1998 gained momentum with the Justice and Development Party (Ak Party) coming to power in 2002 and a historical period of rapprochement began between the two countries. During this period, Türkiye adopted the concept of “zero problems with neighbors” in its foreign policy and deepened its strategic partnerships in the region. Turkish-Syrian relations also developed within this framework, the trade volume between the two countries increased and cooperation was strengthened through mutual visits and diplomatic agreements. However, the Arab Spring that started in 2011 was a sharp turning point in Turkish-Syrian relations. The harsh stance of the Bashar Assad administration against the popular uprisings in Syria caused Türkiye to take a stance against Assad and support opposition groups. This process led to the severing of diplomatic ties between the two countries and the gradual deterioration of relations until 2024. Türkiye directly intervened in the civil war in Syria after the Arab Spring and conducted military operations in northern Syria that highlighted security policies. The main purpose of this study is to examine the transformation in Türkiye's Syria policies between 2002 and 2024 and to analyze the role of domestic political dynamics in Türkiye in this transformation. The main research question of the study is how domestic political actors in Türkiye, especially decision-makers (leaders, governments, political parties), shape foreign policy. In this context, the extent to which the leadership of the Ak Party government is decisive in decision-making processes and how the impact of domestic dynamics on foreign policy emerges will be studied. In this study, how both the pressures of the international system and domestic political dynamics shape foreign policy will be analyzed using the theoretical framework of neoclassical realism. How decision-making processes are decisive in foreign policy will be examined through a case study specific to Türkiye-Syria relations. In addition, the strategic preferences of leaders such as Recep Tayyip Erdoğan and Ahmet Davutoğlu in foreign policy and how these preferences overlap with developments in domestic politics will be evaluated using the discourse analysis method. This study aims to make a new contribution to the literature by providing a comprehensive analysis of how domestic dynamics shape foreign policy in Türkiye-Syria relations.

Keywords: decision-making mechanisms, foreign policy analysis, neoclassical realism, syria, türkiye

Procedia PDF Downloads 2
645 Contributory Antioxidant Role of Testosterone and Oxidative Stress Biomarkers in Males Exposed to Mixed Chemicals in an Automobile Repair Community

Authors: Saheed A. Adekola, Mabel A. Charles-Davies, Ridwan A. Adekola

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Background: Testosterone is a known androgenic and anabolic steroid, primarily secreted in the testes. It plays an important role in the development of testes and prostate and has a range of biological actions. There is evidence that exposure to mixed chemicals in the workplace leads to the generation of free radicals and inadequate antioxidants leading to oxidative stress, which may serve as an early indicator of a pathophysiologic state. Based on findings, testosterone shows direct antioxidant effects by increasing the activities of antioxidant enzymes like glutathione peroxidase, thus indirectly contributing to antioxidant capacity. Objective: To evaluate the antioxidant role of testosterone as well as the relationship between testosterone and oxidative stress biomarkers in males exposed to mixed chemicals in the automobile repair community. Methods: The study included 43 participants aged 22- 60years exposed to mixed chemicals (EMC) from the automobile repair community. Forty (40) apparently healthy, unexposed, age-matched controls were recruited after informed consent. Demographic, sexual and anthropometric characteristics were obtained from pre-test structured questionnaires using standard methods. Blood samples (10mls) were collected from each subject into plain bottles and sera obtained were used for biochemical analyses. Serum levels of testosterone and luteinizing hormone (LH) were determined by enzyme immunoassay method, EIA (Immunometrics UK.LTD). Levels of total antioxidant capacity (TAC), total plasma peroxide (TPP), Malondialdehyde (MDA), hydrogen peroxide (H2O2), glutathione peroxide (GPX), superoxide dismutase (SOD), glutathione-S-transferase (GST), and reduced glutathione (GSH) were determined using spectrophotometric methods respectively. Results obtained were analyzed using the Student’s t-test and Chi-square test for quantitative variables and qualitative variables respectively. Multiple regression was used to find associations and relationships between the variables. Results: Significant higher concentrations of TPP, MDA, OSI, H2O2 and GST were observed in EMC compared with controls (p < 0.001). Within EMC, significantly higher levels of testosterone, LH and TAC were observed in eugonadic when compared with hypogonadic participants (p < 0.001). Diastolic blood pressure, waist circumference, waist height ratio and waist hip ratio were significantly higher in participants EMC compared with the controls. Sexual history and dietary intake showed that the controls had normal erection during sex and took more vegetables in their diet which may therefore be beneficial. Conclusion: The significantly increased levels of total antioxidant capacity in males exposed to mixed chemicals despite their exposure may probably reflect the contributory antioxidant role testosterone that prevents oxidative stress.

Keywords: mixed chemicals, oxidative stress, antioxidant, hypogonadism testosterone

Procedia PDF Downloads 145
644 A Failure to Strike a Balance: The Use of Parental Mediation Strategies by Foster Carers and Social Workers

Authors: Jennifer E Simpson

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Background and purpose: The ubiquitous use of the Internet and social media by children and young people has had a dual effect. The first is to open a world of possibilities and promise that is characterized by the ability to consume and create content, connect with friends, explore and experiment. The second relates to risks such as unsolicited requests, sexual exploitation, cyberbullying and commercial exploitation. This duality poses significant difficulties for a generation of foster carers and social workers who have no childhood experience to draw on in terms of growing up using the Internet, social media and digital devices. This presentation is concerned with the findings of a small qualitative study about the use of digital devices and the Internet by care-experienced young people to stay in touch with their families and the way this was managed by foster carers and social workers using specific parental mediation strategies. The findings highlight that restrictive strategies were used by foster carers and endorsed by social workers. An argument is made for an approach that develops a series of balanced solutions that move foster carers from such restrictive approaches to those that are grounded in co-use and are interpretive in nature. Methods: Using a purposive sampling strategy, 12 triads consisting of care-experienced young people (aged 13-18 years), their foster carers and allocated social workers were recruited. All respondents undertook a semi-structured interview, with the young people detailing what social media apps and other devices they used to contact their families via an Ecomap. The foster carers and social workers shared details of the methods and approaches they used to manage digital devices and the Internet in general. Data analysis was performed using a Framework analytic method to explore the various attitudes, as well as complementary and contradictory perspectives of the young people, their foster carers and allocated social workers. Findings: The majority of foster carers made use of parental mediation strategies that erred on the side of typologies that included setting rules and regulations (restrictive), ad-hoc checking of a young person’s behavior and device (monitoring), and software used to limit or block access to inappropriate websites (technical). It was noted that minimal use was made by foster carers of parental mediation strategies that included talking about content (active/interpretive) or sharing Internet activities (co-use). Amongst the majority of the social workers, they also had a strong preference for restrictive approaches. Conclusions and implications: Trepidations on the part of both foster carers and social workers about the use of digital devices and the Internet meant that the parental strategies used were weighted more towards restriction, with little use made of approaches such as co-use and interpretative. This lack of balance calls for solutions that are grounded in co-use and an interpretive approach, both of which can be achieved through training and support, as well as wider policy change.

Keywords: parental mediation strategies, risk, children in state care, online safety

Procedia PDF Downloads 73
643 Cities Under Pressure: Unraveling Urban Resilience Challenges

Authors: Sherine S. Aly, Fahd A. Hemeida, Mohamed A. Elshamy

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In the face of rapid urbanization and the myriad challenges posed by climate change, population growth, and socio-economic disparities, fostering urban resilience has become paramount. This abstract offers a comprehensive overview of the study on "Urban Resilience Challenges," exploring the background, methodologies, major findings, and concluding insights. The paper unveils a spectrum of challenges encompassing environmental stressors and deep-seated socio-economic issues, such as unequal access to resources and opportunities. Emphasizing their interconnected nature, the study underscores the imperative for holistic and integrated approaches to urban resilience, recognizing the intricate web of factors shaping the urban landscape. Urbanization has witnessed an unprecedented surge, transforming cities into dynamic and complex entities. With this growth, however, comes an array of challenges that threaten the sustainability and resilience of urban environments. This study seeks to unravel the multifaceted urban resilience challenges, exploring their origins and implications for contemporary cities. Cities serve as hubs of economic, social, and cultural activities, attracting diverse populations seeking opportunities and a higher quality of life. However, the urban fabric is increasingly strained by climate-related events, infrastructure vulnerabilities, and social inequalities. Understanding the nuances of these challenges is crucial for developing strategies that enhance urban resilience and ensure the longevity of cities as vibrant and adaptive entities. This paper endeavors to discern strategic guidelines for enhancing urban resilience amidst the dynamic challenges posed by rapid urbanization. The study aims to distill actionable insights that can inform strategic approaches. Guiding the formulation of effective strategies to fortify cities against multifaceted pressures. The study employs a multifaceted approach to dissect urban resilience challenges. A qualitative method will be employed, including comprehensive literature reviews and data analysis of urban vulnerabilities that provided valuable insights into the lived experiences of resilience challenges in diverse urban settings. In conclusion, this study underscores the urgency of addressing urban resilience challenges to ensure the sustained vitality of cities worldwide. The interconnected nature of these challenges necessitates a paradigm shift in urban planning and governance. By adopting holistic strategies that integrate environmental, social, and economic considerations, cities can navigate the complexities of the 21st century. The findings provide a roadmap for policymakers, planners, and communities to collaboratively forge resilient urban futures that withstand the challenges of an ever-evolving urban landscape.

Keywords: resilient principles, risk management, sustainable cities, urban resilience

Procedia PDF Downloads 54
642 Catalytic Ammonia Decomposition: Cobalt-Molybdenum Molar Ratio Effect on Hydrogen Production

Authors: Elvis Medina, Alejandro Karelovic, Romel Jiménez

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Catalytic ammonia decomposition represents an attractive alternative due to its high H₂ content (17.8% w/w), a product stream free of COₓ, among others; however, challenges need to be addressed for its consolidation as an H₂ chemical storage technology, especially, those focused on the synthesis of efficient bimetallic catalytic systems, as an alternative to the price and scarcity of ruthenium, the most active catalyst reported. In this sense, from the perspective of rational catalyst design, adjusting the main catalytic activity descriptor, a screening of supported catalysts with different compositional settings of cobalt-molybdenum metals is presented to evaluate their effect on the catalytic decomposition rate of ammonia. Subsequently, a kinetic study on the supported monometallic Co and Mo catalysts, as well as on the bimetallic CoMo catalyst with the highest activity is shown. The synthesis of catalysts supported on γ-alumina was carried out using the Charge Enhanced Dry Impregnation (CEDI) method, all with a 5% w/w loading metal. Seeking to maintain uniform dispersion, the catalysts were oxidized and activated (In-situ activation) using a flow of anhydrous air and hydrogen, respectively, under the same conditions: 40 ml min⁻¹ and 5 °C min⁻¹ from room temperature to 600 °C. Catalytic tests were carried out in a fixed-bed reactor, confirming the absence of transport limitations, as well as an Approach to equilibrium (< 1 x 10⁻⁴). The reaction rate on all catalysts was measured between 400 and 500 ºC at 53.09 kPa NH3. The synergy theoretically (DFT) reported for bimetallic catalysts was confirmed experimentally. Specifically, it was observed that the catalyst composed mainly of 75 mol% cobalt proved to be the most active in the experiments, followed by the monometallic cobalt and molybdenum catalysts, in this order of activity as referred to in the literature. A kinetic study was performed at 10.13 – 101.32 kPa NH3 and at four equidistant temperatures between 437 and 475 °C the data were adjusted to an LHHW-type model, which considered the desorption of nitrogen atoms from the active phase surface as the rate determining step (RDS). The regression analysis were carried out under an integral regime, using a minimization algorithm based on SLSQP. The physical meaning of the parameters adjusted in the kinetic model, such as the RDS rate constant (k₅) and the lumped adsorption constant of the quasi-equilibrated steps (α) was confirmed through their Arrhenius and Van't Hoff-type behavior (R² > 0.98), respectively. From an energetic perspective, the activation energy for cobalt, cobalt-molybdenum, and molybdenum was 115.2, 106.8, and 177.5 kJ mol⁻¹, respectively. With this evidence and considering the volcano shape described by the ammonia decomposition rate in relation to the metal composition ratio, the synergistic behavior of the system is clearly observed. However, since characterizations by XRD and TEM were inconclusive, the formation of intermetallic compounds should be still verified using HRTEM-EDS. From this point onwards, our objective is to incorporate parameters into the kinetic expressions that consider both compositional and structural elements and explore how these can maximize or influence H₂ production.

Keywords: CEDI, hydrogen carrier, LHHW, RDS

Procedia PDF Downloads 56
641 Determining Factors of Suspended Glass Systems with Pre-Stress Cable Truss

Authors: Cemil Atakara, Hüseyin Eryaman

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The use of glass as an envelope of a building has been increasing in the twentieth century. For more transparency and dematerialization new glass facade types have emerged in the past two decades which depends on point fixed glazing system (PFGS). The aim of this study is to analyze of the PFGS systems which are used on the glass curtain wall according to their types, degree, architectural and structural effects. This new system is desired because it enhances the transparency of the façade and it minimizes the component of the frames or of the profiles. This PFGS led to new structural elements which use cables, rods, trusses when designing a glass building facades, this structural element called the suspended glass system with pre-stressed cable truss (SGSPCT) which has been used for the first time in 1980 in Serres building. The twenty glass buildings which are designed in different systems have been analyzed during this study. After these analyses five selected SGSPCT building analyzed deeply and one skeletal frame building selected from Lefkosa redesigned according to the analysis results. These selected buildings have been included of various cable-truss system typologies and degree. The methodology of this study is building analysis method and literature survey with the help of books, articles, magazines, drawings, internet sources and applied connection details of the glass buildings. The selected five glass buildings and case building have been detailed analyzed with their architectural drawings, photographs and details. A gridshell structure can be compared with a shell structure; it consists of discrete members connecting nodal points. As these nodal points lie on the surface of an imaginary shell, their shapes function almost identically. Difference between shell and gridshell structures can be found in the fact that, due to their free-form and thus, due to the presence of bending forces, gridshells are required to resist loading through their cross-section. This research is divided into parts. A general study about the glass building and cable-glass and grid shell system will be done in the first chapters. Structural analyses and detailed analyses with schematic drawings with the plans, sections of the selected buildings will be explained in the second part. The third part it consists of the advantages and disadvantages of the use of the SGSPCT and Grid Shell in architecture. The study consists of four chapters including the introduction chapter. The general information of the SGSPCT and glazing system has been mentioned in the first chapter. Structural features, typologies, transparency principle and analytical information on systems have been explained of the selected buildings in the second chapter. The detailed analyses of case building have been done according to their schematic drawings with the plans, sections in the third chapter. After third chapter SGSPCT discussed on to the case building and selected buildings. SGSPCT systems have been compared with their advantages and disadvantages to the other systems. Advantages of cable-truss systems and SGSPCT have been concluded that the use of glass substrates in the last chapter.

Keywords: cable truss, glass, grid shell, transparency

Procedia PDF Downloads 412
640 The Social Ecology of Serratia entomophila: Pathogen of Costelytra giveni

Authors: C. Watson, T. Glare, M. O'Callaghan, M. Hurst

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The endemic New Zealand grass grub (Costelytra giveni, Coleoptera: Scarabaeidae) is an economically significant grassland pest in New Zealand. Due to their impacts on production within the agricultural sector, one of New Zealand's primary industries, several methods are being used to either control or prevent the establishment of new grass grub populations in the pasture. One such method involves the use of a biopesticide based on the bacterium Serratia entomophila. This species is one of the causative agents of amber disease, a chronic disease of the larvae which results in death via septicaemia after approximately 2 to 3 months. The ability of S. entomophila to cause amber disease is dependant upon the presence of the amber disease associated plasmid (pADAP), which encodes for the key virulence determinants required for the establishment and maintenance of the disease. Following the collapse of grass grub populations within the soil, resulting from either natural population build-up or application of the bacteria, non-pathogenic plasmid-free Serratia strains begin to predominate within the soil. Whilst the interactions between S. entomophila and grass grub larvae are well studied, less information is known on the interactions between plasmid-bearing and plasmid-free strains, particularly the potential impact of these interactions upon the efficacy of an applied biopesticide. Using a range of constructed strains with antibiotic tags, in vitro (broth culture) and in vivo (soil and larvae) experiments were conducted using inoculants comprised of differing ratios of isogenic pathogenic and non-pathogenic Serratia strains, enabling the relative growth of pADAP+ and pADAP- strains under competition conditions to be assessed. In nutrient-rich, the non-pathogenic pADAP- strain outgrew the pathogenic pADAP+ strain by day 3 when inoculated in equal quantities, and by day 5 when applied as the minority inoculant, however, there was an overall gradual decline in the number of viable bacteria for both strains over a 7-day period. Similar results were obtained in additional experiments using the same strains and continuous broth cultures re-inoculated at 24-hour intervals, although in these cultures, the viable cell count did not diminish over the 7-day period. When the same ratios were assessed in soil microcosms with limited available nutrients, the strains remained relatively stable over a 2-month period. Additionally, in vivo grass grub co-infections assays using the same ratios of tagged Serratia strains revealed similar results to those observed in the soil, but there was also evidence of horizontal transfer of pADAP from the pathogenic to the non-pathogenic strain within the larval gut after a period of 4 days. Whilst the influence of competition is more apparent in broth cultures than within the soil or larvae, further testing is required to determine whether this competition between pathogenic and non-pathogenic Serratia strains has any influence on efficacy and disease progression, and how this may impact on the ability of S. entomophila to cause amber disease within grass grub larvae when applied as a biopesticide.

Keywords: biological control, entomopathogen, microbial ecology, New Zealand

Procedia PDF Downloads 156
639 Navigate the Labyrinth of Leadership: Leaders’ Experiences in Saudi Higher Education

Authors: Laila Albughayl

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The purpose of this qualitative case study was to explore Saudi females’ leadership journeys as they navigate the labyrinth of leadership in higher education. To gain a better understanding of how these leaders overcame challenges and accessed support as they progressed through the labyrinth to top positions in Saudi higher education. The significance of this research derived from the premise that leaders need to acquire essential leadership competencies such as knowledge, skills, and practices to effectively lead through economic transformation, growing globalism, and rapidly developing technology in an increasingly diverse world. In addition, understanding Saudi women’s challenges in the labyrinth will encourage policymakers to improve the situation under which these women work. The metaphor ‘labyrinth’ for Eagly and Carli (2007) encapsulates the winding paths, dead ends, and maze-like pathways that are full of challenges and supports that women traverse to access and maintain leadership positions was used. In this study, ‘labyrinth’ was used as the conceptual framework to explore women leaders’ challenges and opportunities in leadership in Saudi higher education. A proposed model for efficient navigation of the labyrinth of leadership was used. This model focused on knowledge, skills, and behaviours (KSB) as the analytical framework for examining responses to the research questions. This research was conducted using an interpretivist qualitative approach. A case study was the methodology used. Semi-structured interviews were the main data collection method. Purposive sampling was used to select ten Saudi leaders in three public universities. In coding, the 6-step framework of thematic analysis for Braun and Clarke was used to identify, analyze, and report themes within the data. NVivo software was also used as a tool to assist with managing and organizing the data. The resultant findings showed that the challenges identified by participants in navigating the labyrinth of leadership in Saudi higher education replicated some of those identified in the literature. The onset findings also revealed that the organizational barriers in Saudi higher education came as the top hindrance to women’s advancement in the labyrinth of leadership, followed by societal barriers. The findings also showed that women’s paths in the labyrinth of leadership in higher education were still convoluted and tedious compared to their male counterparts. In addition, the findings revealed that Saudi women leaders use significant strategies to access leadership posts and effectively navigate the labyrinth; this was not indicated in the literature. In addition, the resultant findings revealed that there are keys that assisted Saudi female leaders in effectively navigating the labyrinth of leadership. For example, the findings indicated that spirituality (religion) was a powerful key that enabled Saudi women leaders to pursue and persist in their leadership paths. Based on participants' experiences, a compass for effective navigation of the labyrinth of leadership in higher education was created for current and aspirant Saudi women leaders to follow. Finally, the findings had several significant implications for practice, policy, theory, and future research.

Keywords: women, leadership, labyrinth, higher education

Procedia PDF Downloads 83
638 Temporal Profile of Exercise-Induced Changes in Plasma Brain-Derived Neurotrophic Factor Levels of Schizophrenic Individuals

Authors: Caroline Lavratti, Pedro Dal Lago, Gustavo Reinaldo, Gilson Dorneles, Andreia Bard, Laira Fuhr, Daniela Pochmann, Alessandra Peres, Luciane Wagner, Viviane Elsner

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Approximately 1% of the world's population is affected by schizophrenia (SZ), a chronic and debilitating neurodevelopmental disorder. Among possible factors, reduced levels of Brain-derived neurotrophic factor (BDNF) has been recognized in physiopathogenesis and course of SZ. In this context, peripheral BDNF levels have been used as a biomarker in several clinical studies, since this neurotrophin is able to cross the blood-brain barrier in a bi-directional manner and seems to present a strong correlation with the central nervous system fluid levels. The patients with SZ usually adopts a sedentary lifestyle, which has been partly associated with the increase in obesity incidence rates, metabolic syndrome, type 2 diabetes and coronary heart disease. On the other hand, exercise, a non-invasive and low cost intervention, has been considered an important additional therapeutic option for this population, promoting benefits to physical and mental health. To our knowledge, few studies have been pointed out that the positive effects of exercise in SZ patients are mediated, at least in part, to enhanced levels of BDNF after training. However, these studies are focused on evaluating the effect of single bouts of exercise of chronic interventions, data concerning the short- and long-term exercise outcomes on BDNF are scarce. Therefore, this study aimed to evaluate the effect of a concurrent exercise protocol (CEP) on plasma BDNF levels of SZ patients in different time-points. Material and Methods: This study was approved by the Research Ethics Committee of the Centro Universitário Metodista do IPA (no 1.243.680/2015). The participants (n=15) were subbmited to the CEP during 90 days, 3 times a week for 60 minutes each session. In order to evaluate the short and long-term effects of exercise, blood samples were collected pre, 30, 60 and 90 days after the intervention began. Plasma BDNF levels were determined with the ELISA method, from Sigma-Aldrich commercial kit (catalog number RAB0026) according to manufacturer's instructions. Results: A remarkable increase on plasma BDNF levels at 90 days after training compared to baseline (p=0.006) and 30 days (p=0.007) values were observed. Conclusion: Our data are in agreement with several studies that show significant enhancement on BDNF levels in response to different exercise protocols in SZ individuals. We might suggest that BDNF upregulation after training in SZ patients acts in a dose-dependent manner, being more pronounced in response to chronic exposure. Acknowledgments: This work was supported by Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS)/Brazil.

Keywords: exercise, BDNF, schizophrenia, time-points

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637 Hyperelastic Constitutive Modelling of the Male Pelvic System to Understand the Prostate Motion, Deformation and Neoplasms Location with the Influence of MRI-TRUS Fusion Biopsy

Authors: Muhammad Qasim, Dolors Puigjaner, Josep Maria López, Joan Herrero, Carme Olivé, Gerard Fortuny

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Computational modeling of the human pelvis using the finite element (FE) method has become extremely important to understand the mechanics of prostate motion and deformation when transrectal ultrasound (TRUS) guided biopsy is performed. The number of reliable and validated hyperelastic constitutive FE models of the male pelvis region is limited, and given models did not precisely describe the anatomical behavior of pelvis organs, mainly of the prostate and its neoplasms location. The motion and deformation of the prostate during TRUS-guided biopsy makes it difficult to know the location of potential lesions in advance. When using this procedure, practitioners can only provide roughly estimations for the lesions locations. Consequently, multiple biopsy samples are required to target one single lesion. In this study, the whole pelvis model (comprised of the rectum, bladder, pelvic muscles, prostate transitional zone (TZ), and peripheral zone (PZ)) is used for the simulation results. An isotropic hyperelastic approach (Signorini model) was used for all the soft tissues except the vesical muscles. The vesical muscles are assumed to have a linear elastic behavior due to the lack of experimental data to determine the constants involved in hyperelastic models. The tissues and organ geometry is taken from the existing literature for 3D meshes. Then the biomechanical parameters were obtained under different testing techniques described in the literature. The acquired parametric values for uniaxial stress/strain data are used in the Signorini model to see the anatomical behavior of the pelvis model. The five mesh nodes in terms of small prostate lesions are selected prior to biopsy and each lesion’s final position is targeted when TRUS probe force of 30 N is applied at the inside rectum wall. Code_Aster open-source software is used for numerical simulations. Moreover, the overall effects of pelvis organ deformation were demonstrated when TRUS–guided biopsy is induced. The deformation of the prostate and neoplasms displacement showed that the appropriate material properties to organs altered the resulting lesion's migration parametrically. As a result, the distance traveled by these lesions ranged between 3.77 and 9.42 mm. The lesion displacement and organ deformation are compared and analyzed with our previous study in which we used linear elastic properties for all pelvic organs. Furthermore, the visual comparison of axial and sagittal slices are also compared, which is taken for Magnetic Resource Imaging (MRI) and TRUS images with our preliminary study.

Keywords: code-aster, magnetic resonance imaging, neoplasms, transrectal ultrasound, TRUS-guided biopsy

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636 Exploring Disengaging and Engaging Behavior of Doctoral Students

Authors: Salome Schulze

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The delay of students in completing their dissertations is a worldwide problem. At the University of South Africa where this research was done, only about a third of the students complete their studies within the required period of time. This study explored the reasons why the students interrupted their studies, and why they resumed their research at a later stage. If this knowledge could be utilised to improve the throughput of doctoral students, it could have significant economic benefits for institutions of higher education while at the same time enhancing their academic prestige. To inform the investigation, attention was given to key theories concerning the learning of doctoral students, namely the situated learning theory, the social capital theory and the self-regulated learning theory, based on the social cognitive theory of learning. Ten students in the faculty of Education were purposefully selected on the grounds of their poor progress, or of having been in the system for too long. The collection of the data was in accordance with a Finnish study, since the two studies had the same aims, namely to investigate student engagement and disengagement. Graphic elicitation interviews, based on visualisations were considered appropriate to collect the data. This method could stimulate the reflection and recall of the participants’ ‘stories’ with very little input from the interviewer. The interviewees were requested to visualise, on paper, their journeys as doctoral students from the time when they first registered. They were to indicate the significant events that occurred and which facilitated their engagement or disengagement. In the interviews that followed, they were requested to elaborate on these motivating or challenging events by explaining when and why they occurred, and what prompted them to resume their studies. The interviews were tape-recorded and transcribed verbatim. Information-rich data were obtained containing visual metaphors. The data indicated that when the students suffered a period of disengagement, it was sometimes related to a lack of self-regulated learning, in particular, a lack of autonomy, and the inability to manage their time effectively. When the students felt isolated from the academic community of practice disengagement also occurred. This included poor guidance by their supervisors, which accordingly deprived them of significant social capital. The study also revealed that situational factors at home or at work were often the main reasons for the students’ procrastinating behaviour. The students, however, remained in the system. They were motivated towards a renewed engagement with their studies if they were self-regulated learners, and if they felt a connectedness with the academic community of practice because of positive relationships with their supervisors and of participation in the activities of the community (e.g., in workshops or conferences). In support of their learning, networking with significant others who were sources of information provided the students with the necessary social capital. Generally, institutions of higher education cannot address the students’ personal issues directly, but they can deal with key institutional factors in order to improve the throughput of doctoral students. It is also suggested that graphic elicitation interviews be used more often in social research that investigates the learning and development of the students.

Keywords: doctoral students, engaging and disengaging experiences, graphic elicitation interviews, student procrastination

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635 Improving Working Memory in School Children through Chess Training

Authors: Veena Easvaradoss, Ebenezer Joseph, Sumathi Chandrasekaran, Sweta Jain, Aparna Anna Mathai, Senta Christy

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Working memory refers to a cognitive processing space where information is received, managed, transformed, and briefly stored. It is an operational process of transforming information for the execution of cognitive tasks in different and new ways. Many class room activities require children to remember information and mentally manipulate it. While the impact of chess training on intelligence and academic performance has been unequivocally established, its impact on working memory needs to be studied. This study, funded by the Cognitive Science Research Initiative, Department of Science & Technology, Government of India, analyzed the effect of one-year chess training on the working memory of children. A pretest–posttest with control group design was used, with 52 children in the experimental group and 50 children in the control group. The sample was selected from children studying in school (grades 3 to 9), which included both the genders. The experimental group underwent weekly chess training for one year, while the control group was involved in extracurricular activities. Working memory was measured by two subtests of WISC-IV INDIA. The Digit Span Subtest involves recalling a list of numbers of increasing length presented orally in forward and in reverse order, and the Letter–Number Sequencing Subtest involves rearranging jumbled alphabets and numbers presented orally following a given rule. Both tasks require the child to receive and briefly store information, manipulate it, and present it in a changed format. The Children were trained using Winning Moves curriculum, audio- visual learning method, hands-on- chess training and recording the games using score sheets, analyze their mistakes, thereby increasing their Meta-Analytical abilities. They were also trained in Opening theory, Checkmating techniques, End-game theory and Tactical principles. Pre equivalence of means was established. Analysis revealed that the experimental group had significant gains in working memory compared to the control group. The present study clearly establishes a link between chess training and working memory. The transfer of chess training to the improvement of working memory could be attributed to the fact that while playing chess, children evaluate positions, visualize new positions in their mind, analyze the pros and cons of each move, and choose moves based on the information stored in their mind. If working-memory’s capacity could be expanded or made to function more efficiently, it could result in the improvement of executive functions as well as the scholastic performance of the child.

Keywords: chess training, cognitive development, executive functions, school children, working memory

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634 Developing a High Performance Cement Based Material: The Influence of Silica Fume and Organosilane

Authors: Andrea Cretu, Calin Cadar, Maria Miclaus, Lucian Barbu-Tudoran, Siegfried Stapf, Ioan Ardelean

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Additives and mineral admixtures have become an integral part of cement-based materials. It is common practice to add silica fume to cement based mixes in order to produce high-performance concrete. There is still a lack of scientific understanding regarding the effects that silica fume has on the microstructure of hydrated cement paste. The aim of the current study is to develop high-performance materials with low permeability and high resistance to flexural stress using silica fume and an organosilane. Organosilane bonds with cement grains and silica fume, influencing both the workability and the final properties of the mix, especially the pore size distributions and pore connectivity. Silica fume is a known pozzolanic agent which reacts with the calcium hydroxide in hydrated cement paste, producing more C-S-H and improving the mechanical properties of the mix. It is believed that particles of silica fume act as capillary pore fillers and nucleation centers for C-S-H and other hydration products. In order to be able to design cement-based materials with added silica fume and organosilane, it is necessary first to understand the formation of the porous network during hydration and to observe the distribution of pores and their connectivity. Nuclear magnetic resonance (NMR) methods in low-fields are non-destructive and allow the study of cement-based materials from the standpoint of their porous structure. Other methods, such as XRD and SEM-EDS, help create a comprehensive picture of the samples, along with the classic mechanical tests (compressive and flexural strength measurements). The transverse relaxation time (T₂) was measured during the hydration of 16 samples prepared with two water/cement ratios (0.3 and 0.4) and different concentrations or organosilane (APTES, up to 2% by mass of cement) and silica fume (up to 6%). After their hydration, the pore size distribution was assessed using the same NMR approach on the samples filled with cyclohexane. The SEM-EDS and XRD measurements were applied on pieces and powders prepared from the samples that were used in mechanical testing, which were kept under water for 28 days. Adding silica fume does not influence the hydration dynamics of cement paste, while the addition of organosilane extends the dormancy stage up to 10 hours. The size distribution of the capillary pores is not influenced by the addition of silica fume or organosilane, while the connectivity of capillary pores is decreased only when there is organosilane in the mix. No filling effect is observed even at the highest concentration of silica fume. There is an apparent increase in flexural strength of samples prepared only with silica fume and a decrease for those prepared with organosilane, with a few exceptions. XRD reveals that the pozzolanic reactivity of silica fume can only be observed when there is no organosilane present and the SEM-EDS method reveals the pore distribution, as well as hydration products and the presence or absence of calcium hydroxide. The current work was funded by the Romanian National Authority for Scientific Research, CNCS – UEFISCDI, through project PN-III-P2-2.1-PED-2016-0719.

Keywords: cement hydration, concrete admixtures, NMR, organosilane, porosity, silica fume

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633 De-Densifying Congested Cores of Cities and Their Emerging Design Opportunities

Authors: Faith Abdul Rasak Asharaf

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Every city has a threshold known as urban carrying capacity based on which it can withstand a particular density of people, above which the city might need to resort to measures like expanding its boundaries or growing vertically. As a result of this circumstance, the number of squatter communities is growing, as is the claustrophobic feeling of being confined inside a "concrete jungle." The expansion of suburbs, commercial areas, and industrial real estate in the areas surrounding medium-sized cities has resulted in changes to their landscapes and urban forms, as well as a systematic shift in their role in the urban hierarchy when functional endowment and connections to other territories are considered. The urban carrying capacity idea provides crucial guidance for city administrators and planners in better managing, designing, planning, constructing, and distributing urban resources to satisfy the huge demands of an evergrowing urban population. An ecological footprint is a criterion of urban carrying capacity, which is the amount of land required to provide humanity with renewable resources and absorb its trash. However, as each piece of land has its unique carrying capacity, including ecological, social, and economic considerations, these metropolitan areas begin to reach a saturation point over time. Various city models have been tried throughout the years to meet the increasing urban population density by moving the zones of work, life, and leisure to achieve maximum sustainable growth. The current scenario is that of a vertical city and compact city concept, in which the maximum density of people is attempted to fit into a definite area using efficient land use and a variety of other strategies, but this has proven to be a very unsustainable method of growth, as evidenced by the COVID-19 period. Due to a shortage of housing and basic infrastructure, densely populated cities gave rise to massive squatter communities, unable to accommodate the overflowing migrants. To achieve optimum carrying capacity, planning measures such as polycentric city and diffuse city concepts can be implemented, which will help to relieve the congested city core by relocating certain sectors of the town to the city periphery, which will help to create newer spaces for design in terms of public space, transportation, and housing, which is a major concern in the current scenario. The study's goal is focused on suggesting design options and solutions in terms of placemaking for better urban quality and urban life for the citizens once city centres have been de-densified based on urban carrying capacity and ecological footprint, taking the case of Kochi as an apt example of a highly densified city core, focusing on Edappally, which is an agglomeration of many urban factors.

Keywords: urban carrying capacity, urbanization, urban sprawl, ecological footprint

Procedia PDF Downloads 79