Search results for: Marangoni stress
442 Advancing Microstructure Evolution in Tungsten Through Rolling in Laser Powder Bed Fusion
Authors: Narges Shayesteh Moghaddam
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Tungsten (W), a refractory metal known for its remarkably high melting temperature, offers tremendous potential for use in challenging environments prevalent in sectors such as space exploration, defense, and nuclear industries. Additive manufacturing, especially the Laser Powder-Bed Fusion (LPBF) technique, emerges as a beneficial method for fabricating tungsten parts. This technique enables the production of intricate components while simultaneously reducing production lead times and associated costs. However, the inherent brittleness of tungsten and its tendency to crack under high-temperature conditions pose significant challenges to the manufacturing process. Our research primarily focuses on the process of rolling tungsten parts in a layer-by-layer manner in LPBF and the subsequent changes in microstructure. Our objective is not only to identify the alterations in the microstructure but also to assess their implications on the physical properties and performance of the fabricated tungsten parts. To examine these aspects, we conducted an extensive series of experiments that included the fabrication of tungsten samples through LPBF and subsequent characterization using advanced materials analysis techniques. These investigations allowed us to scrutinize shifts in various microstructural features, including, but not limited to, grain size and grain boundaries occurring during the rolling process. The results of our study provide crucial insights into how specific factors, such as plastic deformation occurring during the rolling process, influence the microstructural characteristics of the fabricated parts. This information is vital as it provides a foundation for understanding how the parameters of the layer-by-layer rolling process affect the final tungsten parts. Our research significantly broadens the current understanding of microstructural evolution in tungsten parts produced via the layer-by-layer rolling process in LPBF. The insights obtained will play a pivotal role in refining and optimizing manufacturing parameters, thus improving the mechanical properties of tungsten parts and, therefore, enhancing their performance. Furthermore, these findings will contribute to the advancement of manufacturing techniques, facilitating the wider application of tungsten parts in various high-demand sectors. Through these advancements, this research represents a significant step towards harnessing the full potential of tungsten in high-temperature and high-stress applications.Keywords: additive manufacturing, rolling, tungsten, refractory materials
Procedia PDF Downloads 101441 Patients in Opioid Maintenance Programs: Psychological Features that Predict Abstinence
Authors: Janaina Pereira, Barbara Gonzalez, Valentina Chitas, Teresa Molina
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Intro: The positive impact of opioid maintenance programs on the health of heroin addicts, and on public health in general, has been widely recognized, namely on the prevalence reduction of infectious diseases as HIV, and on the social reintegration of this population. Nevertheless, a part of patients in these programs cannot remain heroin abstinent, or has relapses, during the treatment. Method: Thus, this cross-sectional research aims at analyzing the relation between a set of psychological and psychosocial variables, which have been associated with the onset of heroin use, and assess if they are also associated with absence of abstinence in participants in an opioid maintenance program. A total of 62 patients, aged between 26 and 58 years old (M= 40.87, DP= 7.39) with a time in opioid maintenance program between 1 and 10 years (M= 5.42, DP= 3.05), 77.4% male and 22.6% female, participated in this research. To assess the criterion variable (heroin use) we used the mean value of positive results in urine tests during the participation in the program, weighted according to the number of months in program. The predictor variables were the coping strategies, the dispositional sensation seeking, and the existence of Posttraumatic stress disorder (PTSD). Results: The results showed that only 33.87% of the patients were totally abstinent of heroin use since the beginning of the program, and the absence of abstinence, as the number of positive heroin tests, was primarily predicted by less proactive coping, and secondarily by a higher level of sensation seeking. 16.13% of the sample fulfilled diagnosis criteria for PTSD, and 67.74 % had at least one traumatic experience throughout their lives. The total of PTSD symptoms had a positive correlation with the number of physical health problems, and with the lack of professional occupation. These results have several implications for the clinical practice in this field, and we suggest the promotion of proactive coping strategies should integrate these opioid maintenance programs, as they represent the tendency to face future events as challenges and opportunities, being positively related to positive results on several fields. The early identification of PTSD in the participants, before entering the opioid maintenance programs, would be important as it is related to negative features that hinder social reintegration, Finally, to identify individuals with a sensation seeking profile would be relevant, not only because they face a higher risk of relapse, but also because the therapeutical approaches should not ignore this dispositional feature in the alternatives they propose to the patients.Keywords: opioid maintenance programs, proactive coping, PTSD, sensation seeking
Procedia PDF Downloads 131440 Factors in a Sustainability Assessment of New Types of Closed Cavity Facades
Authors: Zoran Veršić, Josip Galić, Marin Binički, Lucija Stepinac
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With the current increase in CO₂ emissions and global warming, the sustainability of both existing and new solutions must be assessed on a wide scale. As the implementation of closed cavity facades (CCF) is on the rise, a variety of factors must be included in the analysis of new types of CCF. This paper aims to cover the relevant factors included in the sustainability assessment of new types of CCF. Several mathematical models are being used to describe the physical behavior of CCF. Depending on the type of CCF, they cover the main factors which affect the durability of the façade: thermal behavior of various elements in the façade, stress, and deflection of the glass panels, pressure inside a cavity, exchange rate, and the moisture buildup in the cavity. CCF itself represents a complex system in which all mentioned factors must be considered mutually. Still, the façade is only an envelope of a more complex system, the building. Choice of the façade dictates the heat loss and the heat gain, thermal comfort of inner space, natural lighting, and ventilation. Annual consumption of energy for heating, cooling, lighting, and maintenance costs will present the operational advantages or disadvantages of the chosen façade system in both the economic and environmental aspects. Still, the only operational viewpoint is not all-inclusive. As the building codes constantly demand higher energy efficiency as well as transfer to renewable energy sources, the ratio of embodied and lifetime operational energy footprint of buildings is changing. With the drop in operational energy CO₂ emissions, embodied energy emissions present a larger and larger share in the lifecycle emissions of the building. Taken all into account, the sustainability assessment of a façade, as well as other major building elements, should include all mentioned factors during the lifecycle of an element. The challenge of such an approach is a timescale. Depending on the climatic conditions on the building site, the expected lifetime of CCF can exceed 25 years. In such a time span, some of the factors can be estimated more precisely than others. The ones depending on the socio-economic conditions are more likely to be harder to predict than the natural ones like the climatic load. This work recognizes and summarizes the relevant factors needed for the assessment of new types of CCF, considering the entire lifetime of a façade element and economic and environmental aspects.Keywords: assessment, closed cavity façade, life cycle, sustainability
Procedia PDF Downloads 196439 Impact of Ethnic and Religious Identity on Coping Behavior in Young Adults: Cross-Cultural Research
Authors: Yuliya Kovalenko
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Given the social nature of people, it is interesting to explore strategies of responding to psycho-traumatic situations in individuals of different ethnic and religious identity. This would allow to substantially expand the idea of human behavior in general, and coping behavior, in particular. This paper investigated the weighted impact of ethnic and religious identities on the patterns of coping behavior. This cross-cultural research empirically revealed intergroup differences in coping strategies and behavior in the samples of young students and teachers of different ethnic identities (Egyptians N=216 and Ukrainians N=109) and different religious identities (Egyptian Muslims N=147 and Christians, including Egyptian Christians N=68 and Ukrainian Christians N = 109). The empirical data were obtained using the questionnaires SACS and COPE. Statistical analysis and interpretation of the results were performed with IBM SPSS-23.0. It was found that, compared to the religious identity, the ethnic identity of the subjects appeared more predictive of coping behavior. It was shown that the constant exchange of information and the unity of biological and social contributed to a more homogeneous picture in the society where Christians and Muslims were integrated into a single cultural space. It was concluded that depending on their ethnic identity, individuals would form a specific hierarchy of coping strategies resulting in a specific pattern of coping with certain stressors. The Egyptian subjects revealed the following pattern of coping with various kinds of academic stress: 'seeking social support', 'problem solving', 'adapting', 'seeking information'. The coping pattern demonstrated by the Ukrainian subjects could be presented as 'seeking information', 'adapting', 'seeking social support', 'problem solving'. There was a tendency in the group of Egyptians to engage in more collectivist coping strategies (with the predominant coping strategy 'religious coping'), in contrast to the Ukrainians who displayed more individualistic coping strategies (with 'planning' and 'active coping' as the mostly used coping strategies). At the same time, it was obvious that Ukrainians should not be unambiguously attributed to the individualistic coping behavior due to their reliance on 'seeking social support' and 'social contact'. The final conclusion was also drawn from the peculiarities of developing religious identity, including religiosity, in Egyptians (formal religious education of both Muslims and Christians) and Ukrainians (more spontaneous process): Egyptians seem to learn to resort to the religious coping, which could be an indication that, in principle, it is possible and necessary to train individuals in desirable coping behavior.Keywords: coping behavior, cross-cultural research, ethnic and religious identity, hierarchical pattern of coping
Procedia PDF Downloads 163438 Dynamic Changes of Shifting Cultivation: Past, Present and Future Perspective of an Agroforestry System from Sri Lanka
Authors: Thavananthan Sivananthawerl
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Shifting cultivation (Chena, Slash & Burn) is a cultivation method of raising, primarily, food crops (mainly annual) where an area of land is cleared off for its vegetation and cultivated for a period, and the abandoned (fallow) for its fertility to be naturally restored. Although this is the oldest (more than 5000 years) farming system, it is still practiced by indigenous communities of several countries such as Sri Lanka, India, Indonesia, Malaysia, Myanmar, West & Central Africa, and Amazon rainforest area. In Sri Lanka, shifting cultivation is mainly practiced during the North-East monsoon (called as Maha season, from Sept. to Dec.) with no irrigation. The traditional system allows farmers to cultivate for a short period of cultivation and a long period fallow period. This was facilitated mainly by the availability of land with less population. In addition, in the old system, cultivation practices were mostly related to religious and spiritual practices (Astrology, dynamic farming, etc.). At present, the majority of the shifting cultivators (SC’s) are cultivating in government lands, and most of them are adopting new technology (seeds, agrochemicals, machineries). Due to the local demand, almost 70% of the SC’s growing maize is mono-crop, and the rest with mixed-crop, such as groundnut, cowpea, millet, and vegetables. To ensure continuous cultivation and reduce moisture stress, they established ‘dug wells’ and used pumps to lift water from nearby sources. Due to this, the fallow period has been reduced drastically to 1- 2 years. To have the future prosperous of system, farmers should be educated so that they can understand the harmful effects of shifting cultivation and require new policies and a framework for converting the land use pattern towards high economic returns (new crop varieties, maintaining soil fertility, reducing soil erosion) while protecting the natural forests. The practice of agroforestry should be encouraged in which both the crops and the tall trees are cared for by farmers simultaneously. To facilitate the continuous cultivation, the system needs to develop water harvesting, water-conserving technologies, and scientific water management for the limited rainy season. Even though several options are available, all the solutions vary from region to region. Therefore, it is only the government and cultivators together who can find solutions to the problems of the specific areas.Keywords: shifting cultivation, agroforestry, fallow, economic returns, government, Sri Lanka
Procedia PDF Downloads 98437 Strategic Risk Issues for Film Distributors of Hindi Film Industry in Mumbai: A Grounded Theory Approach
Authors: Rashmi Dyondi, Shishir K. Jha
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The purpose of the paper is to address the strategic risk issues surrounding Hindi film distribution in Mumbai for a film distributor, who acts as an entrepreneur when launching a product (movie) in the market (film territory).The paper undertakes a fundamental review of films and risk in the Hindi film industry and applies Grounded Theory technique to understand the complex phenomena of risk taking behavior of the film distributors (both independent and studios) in Mumbai. Rich in-depth interviews with distributors are coded to develop core categories through constant comparison leading to conceptualization of the phenomena of interest. This paper is a first-of-its-kind-attempt to understand risk behavior of a distributor, which is akin to entrepreneurial risk behavior under conditions of uncertainty. Unlike extensive scholarly work on dynamics of Hollywood motion picture industry, Hindi film industry is an under-researched area till now. Especially how do film distributors perceive risk is an unexplored study for the Hindi film industry. Films are unique experience products and the film distributor acts as an entrepreneur assuming high risks given the uncertainty in the motion picture business. With the entry of mighty corporate studios and astronomical film budgets posing serious business threats to the independent distributors, there is a need for an in-depth qualitative enquiry (applying grounded theory technique) for unraveling the definition of risk for the independent distributors in Mumbai vis-à-vis the corporate studios. Need for good content was a common challenge to both the groups in the present state of the industry, however corporate studios with their distinct ideologies, focus on own productions and financial power faced different set of challenges than the independents (like achieving sustainability in business). Softer issues like market goodwill and relations with producers, honesty in business dealings and transparency came out to be clear markers for success of independents in long run. The findings from the qualitative analysis stress on different elements of risk and challenges as perceived by the two groups of distributors in the Hindi film industry and provide a future research agenda for empirical investigation of determinants of box-office success of Hindi films distributed in Mumbai.Keywords: entrepreneurial risk behavior, film distribution strategy, Hindi film industry, risk
Procedia PDF Downloads 316436 Interactive Garments: Flexible Technologies for Textile Integration
Authors: Anupam Bhatia
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Upon reviewing the literature and the pragmatic work done in the field of E- textiles, it is observed that the applications of wearable technologies have found a steady growth in the field of military, medical, industrial, sports; whereas fashion is at a loss to know how to treat this technology and bring it to market. The purpose of this paper is to understand the practical issues of integration of electronics in garments; cutting patterns for mass production, maintaining the basic properties of textiles and daily maintenance of garments that hinder the wide adoption of interactive fabric technology within Fashion and leisure wear. To understand the practical hindrances an experimental and laboratory approach is taken. “Techno Meets Fashion” has been an interactive fashion project where sensor technologies have been embedded with textiles that result in set of ensembles that are light emitting garments, sound sensing garments, proximity garments, shape memory garments etc. Smart textiles, especially in the form of textile interfaces, are drastically underused in fashion and other lifestyle product design. Clothing and some other textile products must be washable, which subjects to the interactive elements to water and chemical immersion, physical stress, and extreme temperature. The current state of the art tends to be too fragile for this treatment. The process for mass producing traditional textiles becomes difficult in interactive textiles. As cutting patterns from larger rolls of cloth and sewing them together to make garments breaks and reforms electronic connections in an uncontrolled manner. Because of this, interactive fabric elements are integrated by hand into textiles produced by standard methods. The Arduino has surely made embedding electronics into textiles much easier than before; even then electronics are not integral to the daily wear garments. Soft and flexible interfaces of MEMS (micro sensors and Micro actuators) can be an option to make this possible by blending electronics within E-textiles in a way that’s seamless and still retains functions of the circuits as well as the garment. Smart clothes, which offer simultaneously a challenging design and utility value, can be only mass produced if the demands of the body are taken care of i.e. protection, anthropometry, ergonomics of human movement, thermo- physiological regulation.Keywords: ambient intelligence, proximity sensors, shape memory materials, sound sensing garments, wearable technology
Procedia PDF Downloads 394435 The Employment Experiences of Qualified Refugees in the UK and the Impact on Identity, Integration, and Wellbeing: A Qualitative Enquiry
Authors: Amina El-Warari, Agata Vitale, Laura Caulfield, Jennifer Kinloch
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Background: Unemployment levels among refugees in the UK are much higher than voluntary migrants and UK-born citizens. The lack of employment and/or of suitable employment has detrimental consequences on refugees’ ability to integrate and become active citizens in the host country. Research indicates that, when individuals are forced to migrate, one of the most significant aspects to building their identity is their previous profession; this particularly applies to qualified refugees. Despite this, there is little support available to them. The current study is set in this context and aims to explore highly qualified refugees’ employment-related experiences in the UK as well as their suggestions on how to develop specific interventions that can support them in finding suitable employment. Methods: A qualitative study design was employed. Qualitative methods are in fact well suited to research with refugees, as they allow them to give their direct opinion, rather than this being filtered by stakeholders. Listening to ‘the refugee’s voice’ means developing ‘a refugee centered perspective’ where the diverse narratives told by participants are organized to tell their direct collective story. A total of 12 refugees, attending a non-profit refugee organization in the south-west of England, took part in the study. The selection criteria were being over 18, having a level of English that allows them to sustain a conversation, and having a University degree and/or professional qualification. All participants were interviewed individually; the data were transcribed and analyzed thematically. Findings: Participants had very little support in finding suitable employment; this often only consisted of a few sessions in their local job centers and English tutorials. They indicated that being unemployed/underemployed negatively affected their sense of identity, their acculturative stress, and their in-group/ out-group relations. They suggested that specific employment interventions for qualified refugees should be delivered to them individually in order to address their specific needs. Furthermore, most participants suggested that these interventions should support them in volunteering in organizations that match their skills/ qualifications. They also indicated that the employment interventions should support them in having their qualifications recognized in the UK as well as building links with universities/ centers where they can receive adequate training on how to understand and adapt to the employments needs in the UK. Conclusions: These findings will provide the basis for the second stage of the research where specific employment interventions will be designed and tested with highly qualified refugees. In addition, these findings shed light refugee integration policy.Keywords: employment interventions, identity, integration, qualified refugees
Procedia PDF Downloads 268434 The Effects of Molecular and Climatic Variability on the Occurrence of Aspergillus Species and Aflatoxin Production in Commercial Maize from Different Agro-climatic Regions in South Africa
Authors: Nji Queenta Ngum, Mwanza Mulunda
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Introduction Most African research reports on the frequent aflatoxin contamination of various foodstuffs, with researchers rarely specifying which of the Aspergillus species are present in these commodities. Numerous research works provide evidence of the ability of fungi to grow, thrive, and interact with other crop species and focus on the fact that these processes are largely affected by climatic variables. South Africa is a water-stressed country with high spatio-temporal rainfall variability; moreover, temperatures have been projected to rise at a rate twice the global rate. This weather pattern change may lead to crop stress encouraging mold contamination with subsequent mycotoxin production. In this study, the biodiversity and distribution of Aspergillus species with their corresponding toxins in maize from six distinct maize producing regions with different weather patterns in South Africa were investigated. Materials And Methods By applying cultural and molecular methods, a total of 1028 maize samples from six distinct agro-climatic regions were examined for contamination by the Aspergillus species while the high performance liquid chromatography (HPLC) method was applied to analyse the level of contamination by aflatoxins. Results About 30% of the overall maize samples were contaminated by at least one Aspergillus species. Less than 30% (28.95%) of the 228 isolates subjected to the aflatoxigenic test was found to possess at least one of the aflatoxin biosynthetic genes. Furthermore, almost 20% were found to be contaminated with aflatoxins, with mean total aflatoxin concentration levels of 64.17 ppb. Amongst the contaminated samples, 59.02% had mean total aflatoxin concentration levels above the SA regulatory limit of 20ppb for animals and 10 for human consumption. Conclusion In this study, climate variables (rainfall reduction) were found to significantly (p<0.001) influence the occurrence of the Aspergillus species (especially Aspergillus fumigatus) and the production of aflatoxin in South Africa commercial maize by maize variety, year of cultivation as well as the agro-climatic region in which the maize is cultivated. This included, amongst others, a reduction in the average annual rainfall of the preceding year to about 21.27 mm, and, as opposed to other regions whose average maximum rainfall ranged between 37.24 – 44.1 mm, resulted in a significant increase in the aflatoxin contamination of maize.Keywords: aspergillus species, aflatoxins, diversity, drought, food safety, HPLC and PCR techniques
Procedia PDF Downloads 81433 Effects of Nanoencapsulated Echinacea purpurea Ethanol Extract on the Male Reproductive Function in Streptozotocin-Induced Diabetic Rats
Authors: Jia-Ling Ho, Xiu-Ru Zhang, Zwe-Ling Kong
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Diabetes mellitus (DM) is a major health problem that affects patients’ life quality throughout the world due to its many complications. It characterized by chronic hyperglycemia with oxidative stress, which impaired male reproductive function. Fibroblast growth factor 21 (FGF21) is a metabolic regulator that is required for normal spermatogenesis and protects against diabetes-induced germ cell apoptosis. Echinacea purpurea ethanol extract (EE), which contain phenolic acid and isobutylamide, had been proven to have antidiabetic property. Silica-chitosan nanoparticles (Nano-CS) has drug delivery and controlled release properties. This study aims to investigate whether silica-chitosan nanoparticles encapsulated EE (Nano-EE) had more ameliorating male infertility by analyzing the effect of testicular FGF21. The Nano-EE was characterized before used to treatment the diabetic rat model. Male Sprague-Dawley (SD) rats were obtained and divided into seven groups. A group was no induced Streptozotocin (STZ), marked as normal group. Diabetic rats were induced into diabetes by STZ (33 mg/kg). A diabetic group was no treatment with sample (diabetic control group), and other groups were treatment by Nano-CS (465 mg/kg), Nano-EE (93, 279, 465 mg/kg), and metformin (Met) (200 mg/kg) used as reference drug for 7 weeks. Our results indicated that the average nanoparticle size and zeta potential of Nano-EE were 2630 nm and -21.3 mV, respectively. The encapsulation ratio of Nano-EE was about 70%. It also confirmed the antioxidative activity was unchanged by comparing the DPPH and ABTS scavenging of Nano-EE and EE. In vivo test, Nano-EE can improve the STZ induced hyperglycemia, insulin resistance, and plasma FGF21 levels. Nano-EE has increased sperm motility, mitochondria membrane potential (MMP), plasma testosterone level, and reduction of abnormal sperm, nitric oxide (NO), superoxide production as well as reactive oxygen species (ROS). In addition, in plasma antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD) was increased whereas pro-inflammatory cytokines TNF-α, and IL-1β were decreased. Further, in testis, protein content of FGF21, PGC-1α, and SIRT1 were improved. Nano-EE might improve diabetes-induced down-regulation of testicular FGF21 and SIRT1/PGC-1α signaling hence maintain spermatogenesis.Keywords: diabetes mellitus, Echinacea purpurea, reproductive dysfunction, silica-chitosan nanoparticles
Procedia PDF Downloads 195432 Moderating Effect of Different Social Supports on the Relationship between Workplace Bullying and Intention to Occupation Leave in Nurses
Authors: Chenchieh Chang
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Objectives: This study had two objectives. First, it used affective events theory to investigate the relationship between workplace bullying and the intention to resign in nurses, a topic rarely explored in previous studies. Second, according to the conservation of resource theory, individuals encountering work incidents will utilize resources that are at their disposal to strengthen or weaken the effects of the incidents on them. Such resources include social support that comes from their bosses, colleagues, family, and friends. To answer the question of whether different social supports exert distinct effects on alleviating stress experienced by nurses, this study examined the moderating effects of different social supports on the relationship between workplace bullying and nurses’ intention to resign. Method: This study was approved by an institutional review board (code number: 105070) and adopted purposive sampling to survey 911, full-time nurses. Results: Work-related bullying exerted a significant and positive effect on the intention to resign, whereas bullying pertaining to interpersonal relationships and body-related bullying nonsignificantly affected intention to resign. Support from supervisors enhanced the effect of work-related bullying on an intention to resign, whereas support from colleagues and family did not moderate said effect. Research Limitations/Implications: The self-reporting method and cross-sectional research design adopted in this study might have resulted in common method variance and limited the ability to make causal inferences. This study suggests future studies to obtain measures of predictor and criterion variables from different sources or ensure a temporal, proximal, or psychological separation between predictor and criterion in the collection of data to avoid the common method bias. Practical Implications: First, businesses should establish a friendly work environment and prevent employees from encountering workplace bullying. Second, because social support cannot diminish the effect of workplace bullying on employees’ intention to resign, businesses should offer other means of assistance. For example, business managers may introduce confidential systems for employees to report workplace bullying; or they may establish consultation centers where employees can properly express their thoughts and feelings when encountering workplace bullying.Keywords: workplace bullying, intention to occupation leave, social supports, nurses
Procedia PDF Downloads 116431 The Mediating Role of Positive Psychological Capital in the Relationship between Self-Leadership and Career Maturity among Korean University Students
Authors: Lihyo Sung
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Background: Children and teens in Korea experience extreme levels of academic stress. To perform better on the college entrance exam and gain admission to Korea’s most prestigious universities, they devote a significant portion of their early lives to studying. Because of their excessive preparation for entrance exams, students have become accustomed to passive and involuntary engagement. Any student starting university, however, faces new challenges that require more active involvement and self-regulated practice. As a way to tackle this issue, the study focuses on investigating the mediating effects of positive psychological capital on the relationship between self-leadership and career maturity among Korean university students. Objectives and Hypotheses: The long term goal of this study is to offer insights that promote the use of positive psychological interventions in the development and adaptation of career maturity. The current objective is to assess the role of positive psychological capital as a mediator between self-leadership and career maturity among Korean university students. Based on previous research, the hypotheses are: (a) self-leadership will be positively associated with indices of career maturity, and (b) positive psychological capital will partially or fully mediate the relationship between self-leadership and career maturity. Sample Characteristics and Sample Size: Participants in the current study consisted of undergraduate students enrolled in various courses at 5 large universities in Korea. A total of 181 students participated in the study. Methodology: A quantitative research design was adopted to test the hypotheses proposed in the current study. By using a cross-sectional approach to research, a self-administered questionnaire was used to collect data on indices of positive psychological capital, self-leadership, and career maturity. The data were analyzed by means of Cronbach's alpha, Pierson correlation test, multiple regression, path analysis, and SPSS for Windows version 22.0 using descriptive statistics. Results: Findings showed that positive psychological capital fully mediated the relationship between self-leadership and career maturity. Self-leadership significantly impacted positive psychological capital and career maturity, respectively. Scientific Contribution: The results of the current study provided useful insights into the role of psychological strengths such as positive psychological capital in improving self-leadership and career maturity. Institutions can assist in increasing positive psychological capital through the creation of positive experiences for undergraduate students, such as opportunities for coaching and mentoring.Keywords: career maturity, mediating role, positive psychological capital, self-leadership
Procedia PDF Downloads 129430 Feasibility of Online Health Coaching for Canadian Armed Forces Personnel Receiving Treatment for Depression, Anxiety and PTSD
Authors: Noah Wayne, Andrea Tuka, Adrian Norbash, Bryan Garber, Paul Ritvo
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Program/Intervention Description: The Canadian Armed Forces(CAF) Mental Health Clinicstreat a full spectrum of mental disorder, addictions, and psychosocial issues that include Major Depressive Disorder, Post-Traumatic Stress Disorder, Generalized Anxiety Disorder, and other diagnoses. We evaluated the feasibility of an online health coach interventiondelivering mindfulness based cognitive behavioral therapy (M-CBT) and behaviour changesupport for individuals receiving treatment at CAF Clinics. Participants were provided accounts on NexJ Connected Wellness, a digital health platform, and 16 weeks of phone-based health coaching,emphasizingmild to moderate aerobic exercise, a healthy diet, and M-CBT content. The primary objective was to assess the feasibility of the online deliverywith CAF members. Evaluation Methods: Feasibility was evaluated in terms of recruitment, engagement, and program satisfaction. Weadditionallyevaluatedhealth behavior change, program completion, and mental health symptoms (i.e. PHQ-9, GAD-7, PCL-5) at three time points. Results: Service members were referred from Vancouver, Esquimalt, and Edmonton CAF bases between August 2020 and January 2021. N=106 CAF personnel were referred, and n=77 consented.N=66 participated, and n=44 completed 4-month and follow-up measures. The platform received a mean rating of76.5 on the System Usability Scale, and health coaching was judged the most helpful program feature (95.2% endorsement), while reminders (53.7%), secure messaging (51.2%), and notifications (51.2%) were also identified. Improvements in mental health status during active interventions were observed on the PHQ-9 (-5.4, p<0.001), GAD-7 (-4.0, p<0.001), and PCL-5 (-4.1, p<0.05). Conclusion: Online health coaching was well-received amidst the COVID-19 pandemic and related lockdowns. Uptake and engagement were positively reported. Participants valuedcontacts and reported strong therapeutic alliances with coaches. Healthy diet, regular exercise, and mindfulness practice are important for physical and mental health. Engagements in these behaviors are associated with reduced symptoms. An online health coach program appears feasible for assisting Canadian Armed Forces personnel.Keywords: coaching, CBT, military, depression, mental health, digital
Procedia PDF Downloads 161429 An EEG-Based Scale for Comatose Patients' Vigilance State
Authors: Bechir Hbibi, Lamine Mili
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Understanding the condition of comatose patients can be difficult, but it is crucial to their optimal treatment. Consequently, numerous scoring systems have been developed around the world to categorize patient states based on physiological assessments. Although validated and widely adopted by medical communities, these scores still present numerous limitations and obstacles. Even with the addition of additional tests and extensions, these scoring systems have not been able to overcome certain limitations, and it appears unlikely that they will be able to do so in the future. On the other hand, physiological tests are not the only way to extract ideas about comatose patients. EEG signal analysis has helped extensively to understand the human brain and human consciousness and has been used by researchers in the classification of different levels of disease. The use of EEG in the ICU has become an urgent matter in several cases and has been recommended by medical organizations. In this field, the EEG is used to investigate epilepsy, dementia, brain injuries, and many other neurological disorders. It has recently also been used to detect pain activity in some regions of the brain, for the detection of stress levels, and to evaluate sleep quality. In our recent findings, our aim was to use multifractal analysis, a very successful method of handling multifractal signals and feature extraction, to establish a state of awareness scale for comatose patients based on their electrical brain activity. The results show that this score could be instantaneous and could overcome many limitations with which the physiological scales stock. On the contrary, multifractal analysis stands out as a highly effective tool for characterizing non-stationary and self-similar signals. It demonstrates strong performance in extracting the properties of fractal and multifractal data, including signals and images. As such, we leverage this method, along with other features derived from EEG signal recordings from comatose patients, to develop a scale. This scale aims to accurately depict the vigilance state of patients in intensive care units and to address many of the limitations inherent in physiological scales such as the Glasgow Coma Scale (GCS) and the FOUR score. The results of applying version V0 of this approach to 30 patients with known GCS showed that the EEG-based score similarly describes the states of vigilance but distinguishes between the states of 8 sedated patients where the GCS could not be applied. Therefore, our approach could show promising results with patients with disabilities, injected with painkillers, and other categories where physiological scores could not be applied.Keywords: coma, vigilance state, EEG, multifractal analysis, feature extraction
Procedia PDF Downloads 78428 Numerical Modelling and Experiment of a Composite Single-Lap Joint Reinforced by Multifunctional Thermoplastic Composite Fastener
Authors: Wenhao Li, Shijun Guo
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Carbon fibre reinforced composites are progressively replacing metal structures in modern civil aircraft. This is because composite materials have large potential of weight saving compared with metal. However, the achievement to date of weight saving in composite structure is far less than the theoretical potential due to many uncertainties in structural integrity and safety concern. Unlike the conventional metallic structure, composite components are bonded together along the joints where structural integrity is a major concern. To ensure the safety, metal fasteners are used to reinforce the composite bonded joints. One of the solutions for a significant weight saving of composite structure is to develop an effective technology of on-board Structural Health Monitoring (SHM) System. By monitoring the real-life stress status of composite structures during service, the safety margin set in the structure design can be reduced with confidence. It provides a means of safeguard to minimize the need for programmed inspections and allow for maintenance to be need-driven, rather than usage-driven. The aim of this paper is to develop smart composite joint. The key technology is a multifunctional thermoplastic composite fastener (MTCF). The MTCF will replace some of the existing metallic fasteners in the most concerned locations distributed over the aircraft composite structures to reinforce the joints and form an on-board SHM network system. Each of the MTCFs will work as a unit of the AU and AE technology. The proposed MTCF technology has been patented and developed by Prof. Guo in Cranfield University, UK in the past a few years. The manufactured MTCF has been successfully employed in the composite SLJ (Single-Lap Joint). In terms of the structure integrity, the hybrid SLJ reinforced by MTCF achieves 19.1% improvement in the ultimate failure strength in comparison to the bonded SLJ. By increasing the diameter or rearranging the lay-up sequence of MTCF, the hybrid SLJ reinforced by MTCF is able to achieve the equivalent ultimate strength as that reinforced by titanium fastener. The predicted ultimate strength in simulation is in good agreement with the test results. In terms of the structural health monitoring, a signal from the MTCF was measured well before the load of mechanical failure. This signal provides a warning of initial crack in the joint which could not be detected by the strain gauge until the final failure.Keywords: composite single-lap joint, crack propagation, multifunctional composite fastener, structural health monitoring
Procedia PDF Downloads 165427 Laser-Dicing Modeling: Implementation of a High Accuracy Tool for Laser-Grooving and Cutting Application
Authors: Jeff Moussodji, Dominique Drouin
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The highly complex technology requirements of today’s integrated circuits (ICs), lead to the increased use of several materials types such as metal structures, brittle and porous low-k materials which are used in both front end of line (FEOL) and back end of line (BEOL) process for wafer manufacturing. In order to singulate chip from wafer, a critical laser-grooving process, prior to blade dicing, is used to remove these layers of materials out of the dicing street. The combination of laser-grooving and blade dicing allows to reduce the potential risk of induced mechanical defects such micro-cracks, chipping, on the wafer top surface where circuitry is located. It seems, therefore, essential to have a fundamental understanding of the physics involving laser-dicing in order to maximize control of these critical process and reduce their undesirable effects on process efficiency, quality, and reliability. In this paper, the study was based on the convergence of two approaches, numerical and experimental studies which allowed us to investigate the interaction of a nanosecond pulsed laser and BEOL wafer materials. To evaluate this interaction, several laser grooved samples were compared with finite element modeling, in which three different aspects; phase change, thermo-mechanical and optic sensitive parameters were considered. The mathematical model makes it possible to highlight a groove profile (depth, width, etc.) of a single pulse or multi-pulses on BEOL wafer material. Moreover, the heat affected zone, and thermo-mechanical stress can be also predicted as a function of laser operating parameters (power, frequency, spot size, defocus, speed, etc.). After modeling validation and calibration, a satisfying correlation between experiment and modeling, results have been observed in terms of groove depth, width and heat affected zone. The study proposed in this work is a first step toward implementing a quick assessment tool for design and debug of multiple laser grooving conditions with limited experiments on hardware in industrial application. More correlations and validation tests are in progress and will be included in the full paper.Keywords: laser-dicing, nano-second pulsed laser, wafer multi-stack, multiphysics modeling
Procedia PDF Downloads 213426 Effect of Dietary Organic Zinc Supplementation on Immunocompetance and Reproductive Performance in Rats
Authors: D. Nagalakshmi, S. Parashuramulu K. Sadasiva Rao, G. Aruna, L. Vikram
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The zinc (Zn) is the second most abundant trace element in mammals and birds, forming structural component of over 300 enzymes, playing an important role in anti-oxidant defense, immune response and reproduction. Organic trace minerals are more readily absorbed from the digestive tract and more biologically available compared with its inorganic salt. Thus, the present study was undertaken on 60 adult female Sprague Dawley rats (275±2.04 g) for experimental duration of 12 weeks to investigate the effect of dietary Zn supplementation from various organic sources on immunity, reproduction, oxidative defense mechanism and blood biochemical profile. The rats were randomly allotted to 30 replicates (2 per replicate) which were in turn randomly allotted to 5 dietary treatments varying in Zn source i.e., one inorganic source (Zn carbonate) and 4 organic sources (Zn-proteinate, Zn-propionate, Zn-amino acid complex and Zn-methionine) so as to supply NRC recommended Zn concentration (12 ppm Zn). Supplementation of organic Zn had no effect on various haematological and serum biochemical constituents compared to inorganic Zn fed rats. The TBARS and protein carbonyls concentration in liver indicative of oxidative stress was comparable between various organic and inorganic groups. The glutathione reductase activity in haemolysate (P<0.05) and reduced glutathione concentration in liver (P<0.01) was higher when fed organic Zn and RBC catalase activity was higher (P<0.01) on Zn methionine compared to other organic sources tested and the inorganic source. The humoral immune response assessed as antibody titres against sheep RBC was higher (P<0.05) when fed organic sources of zinc compared to inorganic source. The cell mediated immune response expressed as delayed type hypersensitivity reaction was higher (P<0.05) in rats fed Zn propionate with no effect of other organic Zn sources. The serum progesterone concentration was higher (P<0.05) in rats fed organic Zn sources compared to inorganic zinc. The data on ovarian folliculogenesis indicated that organic Zn supplementation increased (P<0.05) the number of graafian follicles and corpus luteum with no effect on primary, secondary and tertiary follicle number. The study indicated that rats fed organic sources of Zn had higher antioxidant enzyme activities, immune response and serum progesterone concentration with higher number of mature follicles. Though the effect of feeding various organic sources were comparable, rats fed zinc methionine had higher antioxidant activity and cell mediated immune response was higher in rats on Zn propionate.Keywords: organic zinc, immune, rats, reproductive
Procedia PDF Downloads 288425 Pomegranates Attenuates Cognitive and Behavioural Deficts and reduces inflammation in a Transgenic Mice Model of Alzheimer's Disease
Authors: M. M. Essa, S. Subash, M. Akbar, S. Al-Adawi, A. Al-Asmi, G. J. Guillemein
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Objective: Transgenic (tg) mice which contain an amyloid precursor protein (APP) gene mutation, develop extracellular amyloid beta (Aβ) deposition in the brain, and severe memory and behavioural deficits with age. These mice serve as an important animal model for testing the efficacy of novel drug candidates for the treatment and management of symptoms of Alzheimer's disease (AD). Several reports have suggested that oxidative stress is the underlying cause of Aβ neurotoxicity in AD. Pomegranates contain very high levels of antioxidants and several medicinal properties that may be useful for improving the quality of life in AD patients. In this study, we investigated the effect of dietary supplementation of Omani pomegranate extract on the memory, anxiety and learning skills along with inflammation in an AD mouse model containing the double Swedish APP mutation (APPsw/Tg2576). Methods: The experimental groups of APP-transgenic mice from the age of 4 months were fed custom-mix diets (pellets) containing 4% pomegranate. We assessed spatial memory and learning ability, psychomotor coordination, and anxiety-related behavior in Tg and wild-type mice at the age of 4-5 months and 18-19 months using the Morris water maze test, rota rod test, elevated plus maze test, and open field test. Further, inflammatory parameters also analysed. Results: APPsw/Tg2576 mice that were fed a standard chow diet without pomegranates showed significant memory deficits, increased anxiety-related behavior, and severe impairment in spatial learning ability, position discrimination learning ability and motor coordination along with increased inflammation compared to the wild type mice on the same diet, at the age of 18-19 months In contrast, APPsw/Tg2576 mice that were fed a diet containing 4% pomegranates showed a significant improvements in memory, learning, locomotor function, and anxiety with reduced inflammatory markers compared to APPsw/Tg2576 mice fed the standard chow diet. Conclusion: Our results suggest that dietary supplementation with pomegranates may slow the progression of cognitive and behavioural impairments in AD. The exact mechanism is still unclear and further extensive research needed.Keywords: Alzheimer's disease, pomegranates, oman, cognitive decline, memory loss, anxiety, inflammation
Procedia PDF Downloads 531424 Implementing Mindfulness into Wellness Plans: Assisting Individuals with Substance Abuse and Addiction
Authors: Michele M. Mahr
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The purpose of this study is to educate, inform, and facilitate scholarly conversation and discussion regarding the implementation of mindfulness techniques when working with individuals with substance use disorder (SUD) or addictive behaviors in mental health. Mindfulness can be recognized as the present moment, non-judgmental awareness, initiated by concentrated attention that is non-reactive and as openheartedly as possible. Individuals with SUD or addiction typically are challenged with triggers, environmental situations, cravings, or social pressures which may deter them from remaining abstinent from their drug of choice or addictive behavior. Also, mindfulness is recognized as one of the cognitive and behavioral treatment approaches and is both a physical and mental practice that encompasses individuals to become aware of internal situations and experiences with undivided attention. That said, mindfulness may be an effective strategy for individuals to employ during these experiences. This study will reveal how mental health practitioners and addiction counselors may find mindfulness to be an essential component of increasing wellness when working with individuals seeking mental health treatment. To this end, mindfulness is simply the ability individuals have to know what is actually happening as it is occurring and what they are experiencing at the moment. In the context of substance abuse and addiction, individuals may employ breathing techniques, meditation, and cognitive restructuring of the mind to become aware of present moment experiences. Furthermore, the notion of mindfulness has been directly connected to the development of neuropathways. The creation of the neural pathways then leads to creating thoughts which leads to developing new coping strategies and adaptive behaviors. Mindfulness strategies can assist individuals in connecting the mind with the body, allowing the individual to remain centered and focused. All of these mentioned above are vital components to recovery during substance abuse and addiction treatment. There are a variety of therapeutic modalities applying the key components of mindfulness, such as Mindfulness-Based Stress Reduction (MBSR) and Mindfulness-Based Cognitive Therapy for depression (MBCT). This study will provide an overview of both MBSR and MBCT in relation to treating individuals with substance abuse and addiction. The author will also provide strategies for readers to employ when working with clients. Lastly, the author will create and foster a safe space for discussion and engaging conversation among participants to ask questions, share perspectives, and be educated on the numerous benefits of mindfulness within wellness.Keywords: mindfulness, wellness, substance abuse, mental health
Procedia PDF Downloads 80423 Response of Planktonic and Aggregated Bacterial Cells to Water Disinfection with Photodynamic Inactivation
Authors: Thayse Marques Passos, Brid Quilty, Mary Pryce
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The interest in developing alternative techniques to obtain safe water, free from pathogens and hazardous substances, is growing in recent times. The photodynamic inactivation of microorganisms (PDI) is a promising ecologically-friendly and multi-target approach for water disinfection. It uses visible light as an energy source combined with a photosensitiser (PS) to transfer energy/electrons to a substrate or molecular oxygen generating reactive oxygen species, which cause cidal effects towards cells. PDI has mainly been used in clinical studies and investigations on its application to disinfect water is relatively recent. The majority of studies use planktonic cells. However, in their natural environments, bacteria quite often do not occur as freely suspended cells (planktonic) but in cell aggregates that are either freely floating or attached to surfaces as biofilms. Microbes can form aggregates and biofilms as a strategy to protect them from environmental stress. As aggregates, bacteria have a better metabolic function, they communicate more efficiently, and they are more resistant to biocide compounds than their planktonic forms. Among the bacteria that are able to form aggregates are members of the genus Pseudomonas, they are a very diverse group widely distributed in the environment. Pseudomonas species can form aggregates/biofilms in water and can cause particular problems in water distribution systems. The aim of this study was to evaluate the effectiveness of photodynamic inactivation in killing a range of planktonic cells including Escherichia coli DSM 1103, Staphylococcus aureus DSM 799, Shigella sonnei DSM 5570, Salmonella enterica and Pseudomonas putida DSM 6125, and aggregating cells of Pseudomonas fluorescens DSM 50090, Pseudomonas aeruginosa PAO1. The experiments were performed in glass Petri dishes, containing the bacterial suspension and the photosensitiser, irradiated with a multi-LED (wavelengths 430nm and 660nm) for different time intervals. The responses of the cells were monitored using the pour plate technique and confocal microscopy. The study showed that bacteria belonging to Pseudomonads group tend to be more tolerant to PDI. While E. coli, S. aureus, S. sonnei and S. enterica required a dosage ranging from 39.47 J/cm2 to 59.21 J/cm2 for a 5 log reduction, Pseudomonads needed a dosage ranging from 78.94 to 118.42 J/cm2, a higher dose being required when the cells aggregated.Keywords: bacterial aggregation, photoinactivation, Pseudomonads, water disinfection
Procedia PDF Downloads 298422 The Prevalence of Obesity among a Huge Sample of 5-20 Years Old Jordanian Children and Adolescents Based on CDC Criteria
Authors: Walid Al-Qerem, Ruba Zumot
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Background: The rise of obesity among children and adolescents remains a primary challenge for healthcare providers globally and in the Middle East. The aim of the present study is to determine the prevalence of obesity among 5-20 years old Jordanians based on CDC criteria. Method: A total of 5722 Jordanians (37% males; 63% females) aged 5-20 years data were retrieved from the Jordanian Ministry of Health electronic database (Hakeem). As per the CDC selection criteria, the chosen data pertains exclusively to healthy Jordanian children and adolescents who are medically sound, not suffering from health conditions, and not undergoing any treatments that could hinder normal growth patterns, such as severe infection, chronic kidney disease (CKD), Down’s syndrome, attention deficit hyperactivity disorder, cancer, heart disease, lung disease, cystic fibrosis, Crohn’s disease, type 1 diabetes, hormonal disturbances, any stress-related conditions, hormonal therapy such as corticosteroids, Growth hormones (GHS) or gonadotropin-releasing hormone agonists, insulin, and amphetamines or any other stimulants. In addition, participants with missing or invalid data values for anthropometric measurements were excluded from the study. Weight for age and body mass index for age were analyzed comparatively for Jordanian children and adolescents against the international growth standards. The Z-score for each record was computed based on CDC equations. As per CDC classifications, BMI for age percentiles, values ≥85th and < 95th are classified as overweight, and value at ≥ 95th is classified as obesity. Results: The average age of the evaluated sample was 12.33 ±4.39 years (10.79 ±3.39 for males and 13.23 ± 4.66 for females). The mean weight for males and females were 33.16±14.17 Kg and 133.54±17.17 cm for males, 43.86 ±18.82 Kg, and 142.19±18.35 for females, while for BMI the mean was for boys and girls 17.81±3.88 and 20.52±5.03 respectively. The results indicated that based on CDC criteria, 8.9% of males were classified as children/adolescents with overweight, and 9.7% were classified as children/adolescents with obesity, while in females, 17.8% were classified as children/adolescents with overweight and 10.2% were classified as children/adolescents with obesity. Discussion: The high prevalence of obesity reported in the present study emphasizes the importance of applying different strategies to prevent childhood obesity, including encouraging physical activity, promoting healthier food options, and behavioral changes. Conclusion: The results presented in this study indicated the high prevalence of overweight/obesity among Jordanian adolescents and children, which must be tagged by healthcare planners and providers.Keywords: CDC, obesity, childhood, Jordan
Procedia PDF Downloads 59421 The Views of German Preparatory Language Programme Students about German Speaking Activity
Authors: Eda Üstünel, Seval Karacabey
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The students, who are enrolled in German Preparatory Language Programme at the School of Foreign Languages, Muğla Sıtkı Koçman University, Turkey, learn German as a foreign language for two semesters in an academic year. Although the language programme is a skills-based one, the students lack German speaking skills due to their fear of making language mistakes while speaking in German. This problem of incompetency in German speaking skills exists also in their four-year departmental study at the Faculty of Education. In order to address this problem we design German speaking activities, which are extra-curricular activities. With the help of these activities, we aim to lead Turkish students of German language to speak in the target language, to improve their speaking skills in the target language and to create a stress-free atmosphere and a meaningful learning environment to communicate in the target language. In order to achieve these aims, an ERASMUS+ exchange staff (a German trainee teacher of German as a foreign language), who is from Schwabisch Gmünd University, Germany, conducted out-of-class German speaking activities once a week for three weeks in total. Each speaking activity is lasted for one and a half hour per week. 7 volunteered students of German preparatory language programme attended the speaking activity for three weeks. The activity took place at a cafe in the university campus, that’s the reason, we call it as an out-of-class activity. The content of speaking activity is not related to the topics studied at the units of coursebook, that’s the reason, we call this activity as extra-curricular one. For data collection, three tools are used. A questionnaire, which is an adapted version of Sabo’s questionnaire, is applied to seven volunteers. An interview session is then held with each student on individual basis. The interview questions are developed so as to ask students to expand their answers that are given at the questionnaires. The German trainee teacher wrote fieldnotes, in which the teacher described the activity in the light of her thoughts about what went well and which areas were needed to be improved. The results of questionnaires show that six out of seven students note that such an acitivity must be conducted by a native speaker of German. Four out of seven students emphasize that they like the way that the activities are designed in a learner-centred fashion. All of the students point out that they feel motivated to talk to the trainee teacher in German. Six out of seven students note that the opportunity to communicate in German with the teacher and the peers enable them to improve their speaking skills, the use of grammatical rules and the use of vocabulary.Keywords: Learning a Foreign Language, Speaking Skills, Teaching German as a Foreign Language, Turkish Learners of German Language
Procedia PDF Downloads 321420 Antioxidant, Hypoglycemic and Hypotensive Effects Affected by Various Molecular Weights of Cold Water Extract from Pleurotus Citrinopileatus
Authors: Pao-Huei Chen, Shu-Mei Lin, Yih-Ming Weng, Zer-Ran Yu, Be-Jen Wang
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Pancreatic α-amylase and intestinal α-glucosidase are the critical enzymes for the breakdown of complex carbohydrates into di- or mono-saccharide, which play an important role in modulating postprandial blood sugars. Angiotensin converting enzyme (ACE) converts inactive angiotensin-I into active angiotensin-II, which subsequently increase blood pressure through triggering vasoconstriction and aldosterone secretion. Thus, inhibition of carbohydrate-digestion enzymes and ACE will help the management of blood glucose and blood pressure, respectively. Studies showed Pleurotus citrinopileatus (PC), an edible mushroom and commonly cultured in oriental countries, exerted anticancer, immune improving, antioxidative, hypoglycemic and hypolipidemic effects. Previous studies also showed various molecular weights (MW) fractioned from extracts may affect biological activities due to varying contents of bioactive components. Thus, the objective of this study is to investigate the in vitro antioxidant, hypoglycemic and hypotenstive effects and distribution of active compounds of various MWs of cold water extract from P. citrinopileatus (CWEPC). CWEPC was fractioned into four various MW fractions, PC-I (<1 kDa), PC-II (1-3.5 kDa), PC-III (3.5-10 kDa), and PC-IV (>10 kDa), using an ultrafiltration system. The physiological activities, including antioxidant activities, the inhibition capabilities of pancreatic α-amylase, intestinal α-glucosidase, and hypertension-linked ACE, and the active components, including polysaccharides, protein, and phenolic contents, of CWEPC and four fractions were determined. The results showed that fractions with lower MW exerted a higher antioxidant activity (p<0.05), which was positively correlated to the levels of total phenols. In contrast, the inhibition effects on the activities of α-amylase, α-glucosidase, and ACE of PC-IV fraction were significantly higher than CWEPC and the other three low MW fractions (< 10 kDa), which was more related to protein contents. The inhibition capability of CWEPC and PC-IV on α-amylase activity was 1/13.4 to 1/2.7 relative to that of acarbose (positive control), respectively. However, the inhibitory ability of PC-IV on α-glucosidase (IC50 = 0.5 mg/mL) was significantly higher than acarbose (IC50 = 1.7 mg/mL). Kinetic data revealed that PC-IV fraction followed a non-competitive inhibition on α-glucosidase activity. In conclusion, the distribution of various bioactive components contribute to the functions of different MW fractions on oxidative stress prevention, and blood pressure and glucose modulation.Keywords: α-Amylase, angiotensin converting enzyme, α-Glucosidase, Pleurotus citrinopileatus
Procedia PDF Downloads 462419 Associations among Fetuin A, Cortisol and Thyroid Hormones in Children with Morbid Obesity and Metabolic Syndrome
Authors: Mustafa Metin Donma, Orkide Donma
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Obesity is a disease with an ever-increasing prevalence throughout the world. The metabolic network associated with obesity is very complicated. In metabolic syndrome (MetS), it becomes even more difficult to understand. Within this context, hormones, cytokines, and many others participate in this complex matrix. The collaboration among all of these parameters is a matter of great wonder. Cortisol, as a stress hormone, is closely associated with obesity. Thyroid hormones are involved in the regulation of energy as well as glucose metabolism with all of its associates. Fetuin A is known for years; however, the involvement of this parameter in obesity discussions is rather new. Recently, it has been defined as one of the new generation markers of obesity. In this study, the aim was to introduce complex interactions among all to be able to make clear comparisons, at least for a part of this complicated matter. Morbid obese (MO) children participated in the study. Two groups with 46 MO children and 43 with MetS were constituted. All children included in the study were above 99th age- and sex-adjusted body mass index (BMI) percentiles according to World Health Organization criteria. Forty-three morbid obese children in the second group had also MetS components. Informed consent forms were filled by the parents of the participants. The institutional ethics committee has given approval for the study protocol. Data as well as the findings of the study were evaluated from a statistical point of view. Two groups were matched for their age and gender compositions. Significantly higher body mass index (BMI), waist circumference, thyrotropin, and insulin values were observed in the MetS group. Triiodothyronine concentrations did not differ between the groups. Elevated levels for thyroxin, cortisol, and fetuin-A were detected in the MetS group compared to the first group (p > 0.05). In MO MetS- group, cortisol was correlated with thyroxin and fetuin-A (p < 0.05). In the MO MetS+ group, none of these correlations were present. Instead, a correlation between cortisol and thyrotropin was found (p < 0.05). In conclusion, findings have shown that cortisol was the key player in severely obese children. The association of this hormone with the participants of thyroid hormone metabolism was quite important. The lack of association with fetuin A in the morbid obese MetS+ group has suggested the possible interference of MetS components in the behavior of this new generation obesity marker. The most remarkable finding of the study was the unique correlation between cortisol and thyrotropin in the morbid obese MetS+ group, suggesting that thyrotropin may serve as a target along with cortisol in the morbid obese MetS+ group. This association may deserve specific attention during the development of remedies against MetS in the pediatric population.Keywords: children, cortisol, fetuin A, morbid obesity, thyrotropin
Procedia PDF Downloads 182418 Reasons for Food Losses and Waste in Basic Production of Meat Sector in Poland
Authors: Sylwia Laba, Robert Laba, Krystian Szczepanski, Mikolaj Niedek, Anna Kaminska-Dworznicka
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Meat and its products are considered food products, having the most unfavorable effect on the environment that requires rational management of these products and waste, originating throughout the whole chain of manufacture, processing, transport, and trade of meat. From the economic and environmental viewpoints, it is important to limit the losses and food wastage and the food waste in the whole meat sector. The link to basic production includes obtaining raw meat, i.e., animal breeding, management, and transport of animals to the slaughterhouse. Food is any substance or product, intended to be consumed by humans. It was determined (for the needs of the present studies) when the raw material is considered as a food. It is the moment when the animals are prepared to loading with the aim to be transported to a slaughterhouse and utilized for food purposes. The aim of the studies was to determine the reasons for loss generation in the basic production of the meat sector in Poland during the years 2017 – 2018. The studies on food losses and waste in the meat sector in basic production were carried out in two areas: red meat i.e., pork and beef and poultry meat. The studies of basic production were conducted in the period of March-May 2019 at the territory of the whole country on a representative trial of 278 farms, including 102 pork production, 55–beef production, and 121 poultry meat production. The surveys were carried out with the utilization of questionnaires by the PAPI (Paper & Pen Personal Interview) method; the pollsters conducted direct questionnaire interviews. Research results indicate that it is followed that any losses were not recorded during the preparation, loading, and transport of the animals to the slaughterhouse in 33% of the visited farms. In the farms where the losses were indicated, the crushing and suffocations, occurring during the production of pigs, beef cattle and poultry, were the main reasons for these losses. They constituted ca. 40% of the reported reasons. The stress generated by loading and transport caused 16 – 17% (depending on the season of the year) of the loss reasons. In the case of poultry production, in 2017, additionally, 10.7% of losses were caused by inappropriate conditions of loading and transportation, while in 2018 – 11.8%. The diseases were one of the reasons for the losses in pork and beef production (7% of the losses). The losses and waste, generated during livestock production and in meat processing and trade cannot be managed or recovered. They have to be disposed of. It is, therefore, important to prevent and minimize the losses throughout the whole production chain. It is possible to introduce the appropriate measures, connected mainly with the appropriate conditions and methods of animal loading and transport.Keywords: food losses, food waste, livestock production, meat sector
Procedia PDF Downloads 145417 Legal Initiatives for Afghan Humanitarian Crisis
Authors: Fereshteh Ganjavi, Rachel Schaffer, Varsha Jorawar
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Elena’s Light is a non-profit organization focused on building brighter futures for refugees, especially women and children. Our mission is to empower refugee women and children by addressing social, legal, and public health issues that predominantly concern them. Elena’s Light offers a range of services that support refugees from structural disadvantages, cultural and social stress, marginalization, and other stressors related to migration. Using a three-pronged approach, our programs focus on legal advocacy, English language acquisition, and health and wellness. Following the Afghan humanitarian crisis, Elena’s Light has developed and intensified advocacy efforts in the legal realm to address the influx of refugees who desperately need assistance. We developed and hosted a Know Your Rights presentation with local immigration lawyers and professionals in February 2022 on the Afghan Humanitarian Parole, which was very successful with over 100 attendees. Elena’s Light is hosting the second Know Your Rights session in early August 2022 on immigration options for Afghans, including Temporary Protected Status (TPS), asylum, Special Immigrant Visa (SIV), and humanitarian parole. Lastly, EL is also leading the local initiative to develop a pro-bono committee to respond to the overwhelming need for lawyers to work on legal cases for Afghan during this crisis. Furthermore, through our other services, we provide free, in-home customizable ESL tutoring sessions to refugee women with a focus on driver’s education, facilitating acculturation, and improving employment opportunities. We also provide in-home maternal, pediatric, and mental health education and wellness services that are aimed at addressing the explicit and implicit barriers to healthcare for refugee populations. Elena’s Light’s diverse community aims to counter the structural disadvantages and anxiety-inducing emotions and experiences related to being a refugee. We would like to join this International Conference on Refugee Law since protecting refugee rights is our mission. We would like to share what we have learned from our legal initiatives for refugee rights. We would also like to listen, learn from, and discuss with experts and researchers how to better understand and advocate for refugee rights. We hope to improve our understanding of how to provide better legal aid for our clients through this conference.Keywords: legal, advocacy, Afghan humanitarian crisis, policy, pro-bono
Procedia PDF Downloads 136416 Market Solvency Capital Requirement Minimization: How Non-linear Solvers Provide Portfolios Complying with Solvency II Regulation
Authors: Abraham Castellanos, Christophe Durville, Sophie Echenim
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In this article, a portfolio optimization problem is performed in a Solvency II context: it illustrates how advanced optimization techniques can help to tackle complex operational pain points around the monitoring, control, and stability of Solvency Capital Requirement (SCR). The market SCR of a portfolio is calculated as a combination of SCR sub-modules. These sub-modules are the results of stress-tests on interest rate, equity, property, credit and FX factors, as well as concentration on counter-parties. The market SCR is non convex and non differentiable, which does not make it a natural optimization criteria candidate. In the SCR formulation, correlations between sub-modules are fixed, whereas risk-driven portfolio allocation is usually driven by the dynamics of the actual correlations. Implementing a portfolio construction approach that is efficient on both a regulatory and economic standpoint is not straightforward. Moreover, the challenge for insurance portfolio managers is not only to achieve a minimal SCR to reduce non-invested capital but also to ensure stability of the SCR. Some optimizations have already been performed in the literature, simplifying the standard formula into a quadratic function. But to our knowledge, it is the first time that the standard formula of the market SCR is used in an optimization problem. Two solvers are combined: a bundle algorithm for convex non- differentiable problems, and a BFGS (Broyden-Fletcher-Goldfarb- Shanno)-SQP (Sequential Quadratic Programming) algorithm, to cope with non-convex cases. A market SCR minimization is then performed with historical data. This approach results in significant reduction of the capital requirement, compared to a classical Markowitz approach based on the historical volatility. A comparative analysis of different optimization models (equi-risk-contribution portfolio, minimizing volatility portfolio and minimizing value-at-risk portfolio) is performed and the impact of these strategies on risk measures including market SCR and its sub-modules is evaluated. A lack of diversification of market SCR is observed, specially for equities. This was expected since the market SCR strongly penalizes this type of financial instrument. It was shown that this direct effect of the regulation can be attenuated by implementing constraints in the optimization process or minimizing the market SCR together with the historical volatility, proving the interest of having a portfolio construction approach that can incorporate such features. The present results are further explained by the Market SCR modelling.Keywords: financial risk, numerical optimization, portfolio management, solvency capital requirement
Procedia PDF Downloads 118415 CFD Simulation of Spacer Effect on Turbulent Mixing Phenomena in Sub Channels of Boiling Nuclear Assemblies
Authors: Shashi Kant Verma, S. L. Sinha, D. K. Chandraker
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Numerical simulations of selected subchannel tracer (Potassium Nitrate) based experiments have been performed to study the capabilities of state-of-the-art of Computational Fluid Dynamics (CFD) codes. The Computational Fluid Dynamics (CFD) methodology can be useful for investigating the spacer effect on turbulent mixing to predict turbulent flow behavior such as Dimensionless mixing scalar distributions, radial velocity and vortices in the nuclear fuel assembly. A Gibson and Launder (GL) Reynolds stress model (RSM) has been selected as the primary turbulence model to be applied for the simulation case as it has been previously found reasonably accurate to predict flows inside rod bundles. As a comparison, the case is also simulated using a standard k-ε turbulence model that is widely used in industry. Despite being an isotropic turbulence model, it has also been used in the modeling of flow in rod bundles and to produce lateral velocities after thorough mixing of coolant fairly. Both these models have been solved numerically to find out fully developed isothermal turbulent flow in a 30º segment of a 54-rod bundle. Numerical simulation has been carried out for the study of natural mixing of a Tracer (Passive scalar) to characterize the growth of turbulent diffusion in an injected sub-channel and, afterwards on, cross-mixing between adjacent sub-channels. The mixing with water has been numerically studied by means of steady state CFD simulations with the commercial code STAR-CCM+. Flow enters into the computational domain through the mass inflow at the three subchannel faces. Turbulence intensity and hydraulic diameter of 1% and 5.9 mm respectively were used for the inlet. A passive scalar (Potassium nitrate) is injected through the mass fraction of 5.536 PPM at subchannel 2 (Upstream of the mixing section). Flow exited the domain through the pressure outlet boundary (0 Pa), and the reference pressure was 1 atm. Simulation results have been extracted at different locations of the mixing zone and downstream zone. The local mass fraction shows uniform mixing. The effect of the applied turbulence model is nearly negligible just before the outlet plane because the distributions look like almost identical and the flow is fully developed. On the other hand, quantitatively the dimensionless mixing scalar distributions change noticeably, which is visible in the different scale of the colour bars.Keywords: single-phase flow, turbulent mixing, tracer, sub channel analysis
Procedia PDF Downloads 208414 Component Test of Martensitic/Ferritic Steels and Nickel-Based Alloys and Their Welded Joints under Creep and Thermo-Mechanical Fatigue Loading
Authors: Daniel Osorio, Andreas Klenk, Stefan Weihe, Andreas Kopp, Frank Rödiger
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Future power plants currently face high design requirements due to worsening climate change and environmental restrictions, which demand high operational flexibility, superior thermal performance, minimal emissions, and higher cyclic capability. The aim of the paper is, therefore, to investigate the creep and thermo-mechanical material behavior of improved materials experimentally and welded joints at component scale under near-to-service operating conditions, which are promising for application in highly efficient and flexible future power plants. These materials promise an increase in flexibility and a reduction in manufacturing costs by providing enhanced creep strength and, therefore, the possibility for wall thickness reduction. At the temperature range between 550°C and 625°C, the investigation focuses on the in-phase thermo-mechanical fatigue behavior of dissimilar welded joints of conventional materials (ferritic and martensitic material T24 and T92) to nickel-based alloys (A617B and HR6W) by means of membrane test panels. The temperature and external load are varied in phase during the test, while the internal pressure remains constant. At the temperature range between 650°C and 750°C, it focuses on the creep behavior under multiaxial stress loading of similar and dissimilar welded joints of high temperature resistant nickel-based alloys (A740H, A617B, and HR6W) by means of a thick-walled-component test. In this case, the temperature, the external axial load, and the internal pressure remain constant during testing. Numerical simulations are used for the estimation of the axial component load in order to induce a meaningful damage evolution without causing a total component failure. Metallographic investigations after testing will provide support for understanding the damage mechanism and the influence of the thermo-mechanical load and multiaxiality on the microstructure change and on the creep and TMF- strength.Keywords: creep, creep-fatigue, component behaviour, weld joints, high temperature material behaviour, nickel-alloys, high temperature resistant steels
Procedia PDF Downloads 123413 Structural Optimization, Design, and Fabrication of Dissolvable Microneedle Arrays
Authors: Choupani Andisheh, Temucin Elif Sevval, Bediz Bekir
Abstract:
Due to their various advantages compared to many other drug delivery systems such as hypodermic injections and oral medications, microneedle arrays (MNAs) are a promising drug delivery system. To achieve enhanced performance of the MN, it is crucial to develop numerical models, optimization methods, and simulations. Accordingly, in this work, the optimized design of dissolvable MNAs, as well as their manufacturing, is investigated. For this purpose, a mechanical model of a single MN, having the geometry of an obelisk, is developed using commercial finite element software. The model considers the condition in which the MN is under pressure at the tip caused by the reaction force when penetrating the skin. Then, a multi-objective optimization based on non-dominated sorting genetic algorithm II (NSGA-II) is performed to obtain geometrical properties such as needle width, tip (apex) angle, and base fillet radius. The objective of the optimization study is to reach a painless and effortless penetration into the skin along with minimizing its mechanical failures caused by the maximum stress occurring throughout the structure. Based on the obtained optimal design parameters, master (male) molds are then fabricated from PMMA using a mechanical micromachining process. This fabrication method is selected mainly due to the geometry capability, production speed, production cost, and the variety of materials that can be used. Then to remove any chip residues, the master molds are cleaned using ultrasonic cleaning. These fabricated master molds can then be used repeatedly to fabricate Polydimethylsiloxane (PDMS) production (female) molds through a micro-molding approach. Finally, Polyvinylpyrrolidone (PVP) as a dissolvable polymer is cast into the production molds under vacuum to produce the dissolvable MNAs. This fabrication methodology can also be used to fabricate MNAs that include bioactive cargo. To characterize and demonstrate the performance of the fabricated needles, (i) scanning electron microscope images are taken to show the accuracy of the fabricated geometries, and (ii) in-vitro piercing tests are performed on artificial skin. It is shown that optimized MN geometries can be precisely fabricated using the presented fabrication methodology and the fabricated MNAs effectively pierce the skin without failure.Keywords: microneedle, microneedle array fabrication, micro-manufacturing structural optimization, finite element analysis
Procedia PDF Downloads 115