Search results for: feasibility studies
8559 Cellular Mechanisms Involved in the Radiosensitization of Breast- and Lung Cancer Cells by Agents Targeting Microtubule Dynamics
Authors: Elsie M. Nolte, Annie M. Joubert, Roy Lakier, Maryke Etsebeth, Jolene M. Helena, Marcel Verwey, Laurence Lafanechere, Anne E. Theron
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Treatment regimens for breast- and lung cancers may include both radiation- and chemotherapy. Ideally, a pharmaceutical agent which selectively sensitizes cancer cells to gamma (γ)-radiation would allow administration of lower doses of each modality, yielding synergistic anti-cancer benefits and lower metastasis occurrence, in addition to decreasing the side-effect profiles. A range of 2-methoxyestradiol (2-ME) analogues, namely 2-ethyl-3-O-sulphamoyl-estra-1,3,5 (10) 15-tetraene-3-ol-17one (ESE-15-one), 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10),15-tetraen-17-ol (ESE-15-ol) and 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16) were in silico-designed by our laboratory, with the aim of improving the parent compound’s bioavailability in vivo. The main effect of these compounds is the disruption of microtubule dynamics with a resultant mitotic accumulation and induction of programmed cell death in various cancer cell lines. This in vitro study aimed to determine the cellular responses involved in the radiation sensitization effects of these analogues at low doses in breast- and lung cancer cell lines. The oestrogen receptor positive MCF-7-, oestrogen receptor negative MDA-MB-231- and triple negative BT-20 breast cancer cell lines as well as the A549 lung cancer cell line were used. The minimal compound- and radiation doses able to induce apoptosis were determined using annexin-V and cell cycle progression markers. These doses (cell line dependent) were used to pre-sensitize the cancer cells 24 hours prior to 6 gray (Gy) radiation. Experiments were conducted on samples exposed to the individual- as well as the combination treatment conditions in order to determine whether the combination treatment yielded an additive cell death response. Morphological studies included light-, fluorescence- and transmission electron microscopy. Apoptosis induction was determined by flow cytometry employing annexin V, cell cycle analysis, B-cell lymphoma 2 (Bcl-2) signalling, as well as reactive oxygen species (ROS) production. Clonogenic studies were performed by allowing colony formation for 10 days post radiation. Deoxyribonucleic acid (DNA) damage was quantified via γ-H2AX foci and micronuclei quantification. Amplification of the p53 signalling pathway was determined by western blot. Results indicated that exposing breast- and lung cancer cells to nanomolar concentrations of these analogues 24 hours prior to γ-radiation induced more cell death than the compound- and radiation treatments alone. Hypercondensed chromatin, decreased cell density, a damaged cytoskeleton and an increase in apoptotic body formation were observed in cells exposed to the combination treatment condition. An increased number of cells present in the sub-G1 phase as well as increased annexin-V staining, elevation of ROS formation and decreased Bcl-2 signalling confirmed the additive effect of the combination treatment. In addition, colony formation decreased significantly. p53 signalling pathways were significantly amplified in cells exposed to the analogues 24 hours prior to radiation, as was the amount of DNA damage. In conclusion, our results indicated that pre-treatment of breast- and lung cancer cells with low doses of 2-ME analogues sensitized breast- and lung cancer cells to γ-radiation and induced apoptosis more so than the individual treatments alone. Future studies will focus on the effect of the combination treatment on non-malignant cellular counterparts.Keywords: cancer, microtubule dynamics, radiation therapy, radiosensitization
Procedia PDF Downloads 2078558 Neuroendocrine Tumors of the Oral Cavity: A Summarized Overview
Authors: Sona Babu Rathinam, Lavanya Dharmendran, Therraddi Mutthu
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Objectives: The purpose of this paper is to provides an overview of the neuroendocrine tumors that arise in the oral cavity. Material and Methods: An overview of the relevant papers on neuroendocrine tumors of the oral cavity by various authors was studied and summarized. Results: On the basis of the relevant studies, this paper provides an overview of the classification and histological differentiation of the neuroendocrine tumors that arise in the oral cavity. Conclusions: The basis of classification of neuroendocrine tumors is largely determined by their histologic differentiation. Though they reveal biologic heterogeneity, there should be an awareness of the occurrence of such lesions in the oral cavity to enable them to be detected and treated early.Keywords: malignant peripheral nerve sheath tumor, olfactory neuroblastoma, paraganglioma, schwannoma
Procedia PDF Downloads 808557 Antiglycemic Activity of Raw Plant Materials as Potential Components of Functional Food
Authors: Ewa Flaczyk, Monika Przeor, Joanna Kobus-Cisowska, Józef Korczak
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The aim of this paper was to collect the information concerning the most popular raw plant materials of antidiabetic activity, in a context of functional food developing production. The elaboration discusses morphological elements possible for an application in functional food production of the plants such as: common bean, ginger, Ceylon cinnamon, white mulberry, fenugreek, French lilac, ginseng, jambolão, and bitter melon. An activity of bioactive substances contained in these raw plant materials was presented, pointing their antiglycemic and also hypocholesterolemic, antiarthritic, antirheumatic, antibacterial, and antiviral activity in the studies on humans and animals. Also the genesis of functional food definition was presented.Keywords: antiglycemic activity, raw plant materials, functional food, food, nutritional sciences
Procedia PDF Downloads 4708556 Reimagining Urban Food Security Through Informality Practices: The Case of Street Food Vending in Johannesburg, South Africa
Authors: Blessings Masuku
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This study positions itself within the nascent of street food vending that plays a crucial role in addressing urban household food security across the urban landscape of South Africa. The study aimed to understand how various forms of infrastructure systems (i.e., energy, water and sanitation, housing, and transport, among others) intersect with food and urban informality and how vendors and households’ choices and decisions made around food are influenced by infrastructure assemblages. This study noted that most of the literature studies on food security have mainly focused on the rural agricultural sector, with limited attention to urban food security, notably the role of informality practices in addressing urban food insecurity at the household level. This study pays close attention to how informal informality practices such as street food vending can be used as a catalyst to address urban poverty and household food security and steer local economies for sustainable livelihoods of the urban poor who live in the periphery of the city in Johannesburg. This study deconstructs the infrastructure needs of street food vendors, and the aim was to understand how such infrastructure needs intersect with food and policy that governs urban informality practices. The study argues that the decisions and choices of informality actors in the city of Johannesburg are chiefly determined by the assemblages of infrastructure, including regulatory frameworks that govern the informal sector in the city of Johannesburg. A qualitative approach that includes surveys (open-ended questions), archival research (i., e policy and other key document reviews), and key interviews mainly with city officials and informality actors. A thematic analysis was used to analyze the data collected. This study contributes to greater debates on urban studies and burgeoning literature on urban food security in many ways that include Firstly, the pivotal role that the informal food sector, notably street food vending, plays within the urban economy to address urban poverty and household food security, therefore questioning the conservative perspectives that view the informal sector as a hindrance to a ‘modern city’ and an annoyance to ‘modern’ urban spaces. Secondly, this study contributes to the livelihood and coping strategies of the urban poor who, despite harsh and restrictive regulatory frameworks, devise various agentive ways to generate incomes and address urban poverty and food insecurities.Keywords: urban food security, street food vending, informal food sector, infrastructure systems, livelihood strategies, policy framework and governance
Procedia PDF Downloads 628555 Investigating the Role of Organizational Politics in Human Resource Management: Effects on Performance Appraisal and Downsizing Decisions
Authors: Ibrahim Elshaer, Samar Kamel
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Organizational politics (OP) has received a great deal of attention in the management literature due to its popularity, mystery, and potential advantages for those how can use it. It involves the use of power and social networks within an organization to promote interests and gain potential benefits. Its implication for human resource (HR) management decisions is heretofore one of its least studied aspects, and awaits further investigation. Therefore, it is our intention to investigate certain relations between organizational politics and the validity of HR decisions in addition to the expected dysfunctional consequences. The study is undertaken on two HR management practices- Performance appraisal (measured by the distributive justice scale) and downsizing- depending on data gathered from the hotel industry in Egypt; a developing Non-Western country, in which Political practices of HR management are common in public and private organizations. Data was obtained from a survey of 600 employees in the Egyptian hotel industry. A total of 500 responses were attained. 100 uncompleted questionnaires were excluded leaving 400 usable with response rate of around 80%. Structural equation modeling (SEM) was employed to test the causal relationship between the research variables. The analysis of the current study data reveals that organizational politics is negatively linked to the perception of distributive justice of performance appraisal, additionally, the perception of distributive justice in performance appraisal is positively linked to the perception of validity in the downsizing decisions and finally the perception of OP is negatively linked to the perception of downsizing decisions validity. This study makes three important contributions. First although there have been several studies on OP, the majority of these studies have focused on examining its effect on employees’ attitudes in workplace. This empirical study helps in identifying the influence of OP on the effectiveness and success of HR decisions and accordingly the organizational system. Second, it draws attention to OP as an important phenomenon that influence HR management in hospitality industry, since empirical evidences concerning OP in the hospitality management literature are meager. Third, this study contributes to the existing downsizing literature by examining OP and low distributive justice as challenges of the effectiveness of the downsizing process. Finally, to the best of the authors’ knowledge, no empirical study in the tourism and hospitality management literature has examined the effect of OP and distributive justice on the workplace using data gathered from the hotel industry in Egypt; a developing non-Western setting.Keywords: organizational politics, performance appraisal, downsizing, structural equation modeling, hotel industry
Procedia PDF Downloads 4098554 Grape Seed Extract in Prevention and Treatment of Liver Toxic Cirrhosis in Rats
Authors: S. Buloyan, V. Mamikonyan, H. Hakobyan, H. Harutyunyan, H. Gasparyan
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The liver is the strongest regenerating organ of the organism, and even with 2/3 surgically removed, it can regenerate completely. Hence, liver cirrhosis may only develop when the regenerating system is off. We present the results of a comparative study of structural and functional characteristics of rat liver tissue under the conditions of toxic liver cirrhosis development, induced by carbon tetrachloride, and its prevention/treatment by natural compounds with antioxidant and immune stimulating action. Studies were made on Wister rats, weighing 120~140 g. Grape seeds extracts, separately and in combination with well known anticirrhotic drug ursodeoxycholic acid (ursodiol) have demonstrated effectiveness in prevention of liver cirrhosis development and its treatment.Keywords: carbon tetrachloride, GSE, liver cirrhosis, prevention, treatment
Procedia PDF Downloads 4868553 The Desirable Construction of Urbanity in Spaces for Public Use
Authors: Giselly Barros Rodrigues, Carlos Leite de Souza
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In recent years, there has been a great discussion about urbanism, the right to the city, the search for the public space and the occupation and appropriation of people in the spaces of the city. This movement happens all over the world and also in the great Brazilian metropolises. The more human-friendly city - the desirable construction of urbanity - as well as the encouragement of walking or bicycling to the detriment of cars is one of the major issues addressed by urban planners and challenges in the process of reviewing regulatory frameworks. The fact is that even if there are public spaces or space for public use in private areas - it is essential that there be, besides a project focused on the people and the use of space, a good management not to generate excess of control and consequently the segregation between different ethnicities, classes or creed. With the insertion of the Strategic Master Plan of Sao Paulo (2014), there is great incentive for them to implement - in the private spaces - of mixed uses and active facades (Services and commerce in the basement of buildings), these incentives will generate a city for people in the medium and long term. This research seeks to discuss the extent to which these spaces are democratic, what their perceptions are in relation to the space of public use in private areas and why this perception may be the one that was originally idealized. For this study, we carried out bibliographic reviews where applied research were carried out in three case studies listed in Sao Paulo. Questionnaires were also applied to the actors who gave answers regarding their perceptions and how they were approached in the places analyzed. After analyzing the material, it was verified that in the three case studies analyzed, sitting on the floor is prohibited. In the two places in Paulista Avenue (Cetenco Plaza and Square of Mall Cidade Sao Paulo) there was no problem whatsoever in relation to the clothes or attitudes of the actors in the streets of Paulista Avenue in Sao Paulo city. Different from what happened in the Itaim neighborhood (Brascan Century Plaza), with more conservative characteristics, where the actors were heavily watched by security and observed by others due to their clothes and attitudes in that area. The city of Sao Paulo is slowly changing, people are increasingly looking for places of quality in public use in their daily lives. The Strategic Master Plan of Sao Paulo (2014) and the Legislation approved in 2016 envision a city more humane and people-oriented in the future. It is up to the private sector, the public, and society to work together so that this glimpse becomes an abundant reality in every city, generating quality of life and urbanity for all.Keywords: urbanity, space for public use, appropriation of space, segregation
Procedia PDF Downloads 2378552 University Students' Perspectives on a Mindfulness-Based App for Weight, Weight Related Behaviors, and Stress: A Qualitative Focus Group Study
Authors: Lynnette Lyzwinski, Liam Caffery, Matthew Bambling, Sisira Edirippulige
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Introduction: A novel method of delivering mindfulness interventions for populations at risk of weight gain and stress-related eating, in particular, college students, is through mHealth. While there have been qualitative studies on mHealth for weight loss, there has not been a study on mHealth for weight loss using mindfulness that has explored student perspectives on a student centred mindfulness app and mindfulness-based text messages for eating and stress. Student perspective data will provide valuable information for creating a specific purpose weight management app and mindfulness-based text messages (for the Mindfulness App study). Methods: A qualitative focus group study was undertaken at St Lucia campus at the University of Queensland in March 2017. Students over the age of 18 were eligible to participate. Interviews were audiotaped and transcribed. One week following the focus group, students were sent sample mindfulness-based text messages based on their responses. Students provided written feedback via email. Data were analysed using N Vivo software. Results: The key themes in a future mindfulness-based app are a simple design interface, a focus on education/practical tips, and real-life practical exercises. Social media should be avoided. Key themes surrounding barriers include the perceived difficulty of mindfulness and a lack of proper guidance or knowledge. The mindfulness-based text messages were received positively. Key themes were creating messages with practical tips about how to be mindful and how to integrate mindful reflection of both one’s body and environment while on campus. Other themes including creating positive, inspirational messages. There was lack of agreement on the ideal timing for messages. Discussion: This is the first study that explored student perspectives on a mindfulness-app and mindfulness-based text messages for stress and weight management as a pre-trial study for the Mindfulness App trial for stress, lifestyle, and weight in students. It is important to consider maximizing the potential facilitators of use and minimize potential identified barriers when developing and designing a future mHealth mindfulness-based intervention tailored to the student consumer. Conclusion: Future mHealth studies may consider integrating mindfulness-based text messages in their interventions for weight and stress as this is a novel feature that appears to be acceptable for participants. The results of this focus group provide the basis to develop content for a specific purpose student app for weight management.Keywords: mindfulness, college students, mHealth, weight loss
Procedia PDF Downloads 1988551 An Overview of PFAS Treatment Technologies with an In-Depth Analysis of Two Case Studies
Authors: Arul Ayyaswami, Vidhya Ramalingam
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Per- and polyfluoroalkyl substances (PFAS) have emerged as a significant environmental concern due to their ubiquity and persistence in the environment. Their chemical characteristics and adverse effects on human health demands more effective and sustainable solutions in remediation of the PFAS. The work presented here encompasses an overview of treatment technologies with two case studies that utilize effective approaches in addressing PFAS contaminated media. Currently the options for treatment of PFAS compounds include Activated carbon adsorption, Ion Exchange, Membrane Filtration, Advanced oxidation processes, Electrochemical treatment, and Precipitation and Coagulation. In the first case study, a pilot study application of colloidal activated carbon (CAC) was completed to address PFAS from aqueous film-forming foam (AFFF) used to extinguish a large fire. The pilot study was used to demonstrate the effectiveness of a CAC in situ permeable reactive barrier (PRB) in effectively stopping the migration of PFOS and PFOA, moving from the source area at high concentrations. Before the CAC PRB installation, an injection test using - fluorescein dye was conducted to determine the primary fracture-induced groundwater flow pathways. A straddle packer injection delivery system was used to isolate discrete intervals and gain resolution over the 70 feet saturated zone targeted for treatment. Flow rates were adjusted, and aquifer responses were recorded for each interval. The results from the injection test were used to design the pilot test injection plan using CAC PRB. Following the CAC PRB application, the combined initial concentration 91,400 ng/L of PFOS and PFOA were reduced to approximately 70 ng/L (99.9% reduction), after only one month following the injection event. The results demonstrate the remedy's effectiveness to quickly and safely contain high concentrations of PFAS in fractured bedrock, reducing the risk to downgradient receptors. The second study involves developing a reductive defluorination treatment process using UV and electron acceptor. This experiment indicates a significant potential in treatment of PFAS contaminated waste media such as landfill leachates. The technology also shows a promising way of tacking these contaminants without the need for secondary waste disposal or any additional pre-treatments.Keywords: per- and polyfluoroalkyl substances (PFAS), colloidal activated carbon (CAC), destructive PFAS treatment technology, aqueous film-forming foam (AFFF)
Procedia PDF Downloads 598550 Followership Styles in the U.S. Hospitality Workforce: A Multi-Generational Comparison Study
Authors: Yinghua Huang, Tsu-Hong Yen
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The latest advance in leadership research has revealed that leadership is co-created through the combined action of leading and following. The role of followers is as important as leaders in the leadership process. However, the previous leadership studies often conceptualize leadership as a leader-centric process, while the role of followers is largely neglected in the literature. Until recently, followership studies receives more attention because the character and behavior of followers are as vital as the leader during the leadership process. Yet, there is a dearth of followership research in the context of tourism and hospitality industries. Therefore, this study seeks to fill in the gap of knowledge and investigate the followership styles in the U.S. hospitality workforce. In particular, the objectives of this study are to identify popular followership practices among hospitality employees and evaluate hospitality employees' followership styles using Kelley’s followership typology framework. This study also compared the generational differences in followership styles among hospitality employees. According to the U.S. Bureau of Labor Statistics, the workforce in the lodging and foodservice sectors consists of around 12% baby boomers, 29% Gen Xs, 23% Gen Ys, and 36% Gen Zs in 2019. The diversity of workforce demographics in the U.S. hospitality industry calls for more attention to understand the generational differences in followership styles and organizational performance. This study conducted an in-depth interview and a questionnaire survey to collect both qualitative and quantitative data. A snowball sampling method was used to recruit participants working in the hospitality industry in the San Francisco Bay Area, California, USA. A total of 120 hospitality employees participated in this study, including 22 baby boomers, 32 Gen Xs, 30 Gen Ys, and 36 Gen Zs. 45% of the participants were males, and 55% were female. The findings of this study identified good followership practices across the multi-generational participants. For example, a Gen Y participant said that 'followership involves learning and molding oneself after another person usually an expert in an area of interest. I think of followership as personal and professional development. I learn and get better by hands-on training and experience'. A Gen X participant said that 'I can excel by not being fearful of taking on unfamiliar tasks and accepting challenges.' Furthermore, this study identified five typologies of Kelley’s followership model among the participants: 45% exemplary followers, 13% pragmatist followers, 2% alienated followers, 18% passive followers, and 23% conformist followers. The generational differences in followership styles were also identified. The findings of this study contribute to the hospitality human resource literature by identifying the multi-generational perspectives of followership styles among hospitality employees. The findings provide valuable insights for hospitality leaders to understand their followers better. Hospitality leaders were suggested to adjust their leadership style and communication strategies based on employees' different followership styles.Keywords: followership, hospitality workforce, generational diversity, Kelley’s followership topology
Procedia PDF Downloads 1298549 Ionic Liquids-Polymer Nanoparticle Systems as Breakthrough Tools to Improve the Leprosy Treatment
Authors: A. Julio, R. Caparica, S. Costa Lima, S. Reis, J. G. Costa, P. Fonte, T. Santos De Almeida
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The Mycobacterium leprae causes a chronic and infectious disease called leprosy, which the most common symptoms are peripheral neuropathy and deformation of several parts of the body. The pharmacological treatment of leprosy is a combined therapy with three different drugs, rifampicin, clofazimine, and dapsone. However, clofazimine and dapsone have poor solubility in water and also low bioavailability. Thus, it is crucial to develop strategies to overcome such drawbacks. The use of ionic liquids (ILs) may be a strategy to overcome the low solubility since they have been used as solubility promoters. ILs are salts, liquid below 100 ºC or even at room temperature, that may be placed in water, oils or hydroalcoholic solutions. Another approach may be the encapsulation of drugs into polymeric nanoparticles, which improves their bioavailability. In this study, two different classes of ILs were used, the imidazole- and the choline-based ionic liquids, as solubility enhancers of the poorly soluble antileprotic drugs. Thus, after the solubility studies, it was developed IL-PLGA nanoparticles hybrid systems to deliver such drugs. First of all, the solubility studies of clofazimine and dapsone were performed in water and in water: IL mixtures, at ILs concentrations where cell viability is maintained, at room temperature for 72 hours. For both drugs, it was observed an improvement on the drug solubility and [Cho][Phe] showed to be the best solubility enhancer, especially for clofazimine, where it was observed a 10-fold improvement. Later, it was produced nanoparticles, with a polymeric matrix of poly(lactic-co-glycolic acid) (PLGA) 75:25, by a modified solvent-evaporation W/O/W double emulsion technique in the presence of [Cho][Phe]. Thus, the inner phase was an aqueous solution of 0.2 % (v/v) of the above IL with each drug to its maximum solubility determined on the previous study. After the production, the nanosystem hybrid was physicochemically characterized. The produced nanoparticles had a diameter of around 580 nm and 640 nm, for clofazimine and dapsone, respectively. Regarding the polydispersity index, it was in agreement of the recommended value of this parameter for drug delivery systems (around 0.3). The association efficiency (AE) of the developed hybrid nanosystems demonstrated promising AE values for both drugs, given their low solubility (64.0 ± 4.0 % for clofazimine and 58.6 ± 10.0 % for dapsone), that prospects the capacity of these delivery systems to enhance the bioavailability and loading of clofazimine and dapsone. Overall, the study achievement may signify an upgrading of the patient’s quality of life, since it may mean a change in the therapeutic scheme, not requiring doses of drug so high to obtain a therapeutic effect. The authors would like to thank Fundação para a Ciência e a Tecnologia, Portugal (FCT/MCTES (PIDDAC), UID/DTP/04567/2016-CBIOS/PRUID/BI2/2018).Keywords: ionic liquids, ionic liquids-PLGA nanoparticles hybrid systems, leprosy treatment, solubility
Procedia PDF Downloads 1508548 Sampling Effects on Secondary Voltage Control of Microgrids Based on Network of Multiagent
Authors: M. J. Park, S. H. Lee, C. H. Lee, O. M. Kwon
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This paper studies a secondary voltage control framework of the microgrids based on the consensus for a communication network of multiagent. The proposed control is designed by the communication network with one-way links. The communication network is modeled by a directed graph. At this time, the concept of sampling is considered as the communication constraint among each distributed generator in the microgrids. To analyze the sampling effects on the secondary voltage control of the microgrids, by using Lyapunov theory and some mathematical techniques, the sufficient condition for such problem will be established regarding linear matrix inequality (LMI). Finally, some simulation results are given to illustrate the necessity of the consideration of the sampling effects on the secondary voltage control of the microgrids.Keywords: microgrids, secondary control, multiagent, sampling, LMI
Procedia PDF Downloads 3338547 Computer Simulation Studies of Aircraft Wing Architectures on Vibration Responses
Authors: Shengyong Zhang, Mike Mikulich
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Vibration is a crucial limiting consideration in the analysis and design of airplane wing structures to avoid disastrous failures due to the propagation of existing cracks in the material. In this paper, we build CAD models of aircraft wings to capture the design intent with configurations. Subsequent FEA vibration analysis is performed to study the natural vibration properties and impulsive responses of the resulting user-defined wing models. This study reveals the variations of the wing’s vibration characteristics with respect to changes in its structural configurations. Integrating CAD modelling and FEA vibration analysis enables designers to improve wing architectures for implementing design requirements in the preliminary design stage.Keywords: aircraft wing, CAD modelling, FEA, vibration analysis
Procedia PDF Downloads 1658546 Synthesis and Characterization of Silver Nanoparticles Using Daucus carota Extract
Authors: M. R. Bindhu, M. Umadevi
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Silver nanoparticles have been synthesized by Daucus carota extract as reducing agent was reported here. The involvement of phytochemicals in the Daucus carota extract in the reduction and stabilization of silver nanoparticles has been established using XRD and UV-vis studies. The UV-vis spectrum of the prepared silver nanoparticles showed surface plasmon absorbance peak at 450 nm. The obtained silver nanoparticles were almost spherical in shape with the average size of 15 nm. Crystalline nature of the nanoparticles was evident from bright spots in the SAED pattern and peaks in the XRD pattern. This new, simple and natural method for biosynthesis of silver nanoparticles offers a valuable contribution in the area of green synthesis and nanotechnology avoiding the presence of hazardous and toxic solvents and waste.Keywords: Daucus carota, green synthesis, silver nanoparticles, surface plasmon resonance
Procedia PDF Downloads 4688545 The Efficacy of Preoperative Thermal Pulsation Treatment in Reducing Post Cataract Surgery Dry Eye Disease: A Systematic Review and Meta-analysis
Authors: Lugean K. Alomari, Rahaf K. Sharif, Basil K. Alomari, Hind M. Aljabri, Faisal F. Aljahdali, Amal A. Alomari, Saeed A. Alghamdi
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Background: The thermal pulsation system is a therapy that uses heat and massage to treat dry eye disease; thus, some trials have been published to compare it with the conventional treatment. The aim of this study is to conduct a systematic review and meta-analysis comparing the efficacy of thermal pulsation systems with conventional treatment in patients undergoing cataract surgery. Methods: Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for eligible trials. We included three randomized controlled trials (RCTs) that compared the thermal pulsation system with the conventional treatment in patients undergoing cataract surgery. A table of characteristics was plotted, and the Quality of the studies was assessed using the Cochrane risk-of-bias tool for randomized trials (RoB 2). Forest plots were plotted using the Random-effect Inverse Variance method. χ2 test and the Higgins-I-squared (I2) model were used to assess heterogeneity. A total of 201 cataract surgery patients were included, with 105 undergoing preoperative pulsation therapy and 96 receiving conventional treatment. Demographic analysis revealed comparable distributions across groups. Results: All the studies in our analysis are of good quality with a low risk of bias. A total of 201 patients were included in the analysis, out of which 105 underwent pulsation therapy, and 95 were in the control group. Tear Break-up Time (TBUT) analysis revealed no significant baseline differences, except pulsation therapy being better at 1 month. (SMD 0.42 [95%CI 0.14 - 0.70] p=0.004). This positive trend continued at three months (SMD 0.52 [95% CI (0.20 – 0.84)] p=0.002). Corneal fluorescein staining scores and Meibomian gland-yielding secretion scores showed no significant differences at baseline. However, at one month, pulsation therapy significantly improved Meibomian gland function (SMD -0.86 [95% CI (-1.20 - -0.53)] p<0.00001), indicating a reduced risk of dry eye syndrome. Conclusion: Preoperative pulsation therapy appears to enhance post-cataract surgery outcomes, particularly in terms of tear film stability and Meibomian gland secretory function. The sustained positive effects observed at one and three months post-surgery suggest the potential for long-term benefits.Keywords: lipiflow, cataract, thermal pulsation, dry eye
Procedia PDF Downloads 208544 Thermal Modelling and Experimental Comparison for a Moving Pantograph Strip
Authors: Nicolas Delcey, Philippe Baucour, Didier Chamagne, Geneviève Wimmer, Auditeau Gérard, Bausseron Thomas, Bouger Odile, Blanvillain Gérard
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This paper proposes a thermal study of the catenary/pantograph interface for a train in motion. A 2.5D complex model of the pantograph strip has been defined and created by a coupling between a 1D and a 2D model. Experimental and simulation results are presented and with a comparison allow validating the 2.5D model. Some physical phenomena are described and presented with the help of the model such as the stagger motion thermal effect, particular heats and the effect of the material characteristics. Finally it is possible to predict the critical thermal configuration during a train trip.Keywords: electro-thermal studies, mathematical optimizations, multi-physical approach, numerical model, pantograph strip wear
Procedia PDF Downloads 3278543 Some Observations on the Preparation of Zinc Hydroxide Nitrate Nanoparticles
Authors: Krasimir Ivanov, Elitsa Kolentsova, Nguyen Nguyen, Alexander Peltekov, Violina Angelova
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The nanosized zinc hydroxide nitrate has been recently estimated as perspective foliar fertilizer, which has improved zinc solubility, but low phytotoxicity, in comparison with ZnO and other Zn containing compounds. The main problem is obtaining of stable particles with dimensions less than 100 nm. This work studies the effect of preparation conditions on the chemical compositions and particle size of the zinc hydroxide nitrates, prepared by precipitation. Zn(NO3)2.6H2O and NaOH with concentrations, ranged from 0.2 to 3.2M and the initial OH/Zn ratio from 0.5 to 1.6 were used at temperatures from 20 to 60 °C. All samples were characterized in detail by X-ray diffraction, scanning electron microscopy, differential thermal analysis and ICP. Stability and distribution of the zinc hydroxide nitrate particles were estimated too.Keywords: zinc hydroxide nitrate, nanoparticles, preparation, foliar fertilizer
Procedia PDF Downloads 3498542 Understanding the Challenges of Lawbook Translation via the Framework of Functional Theory of Language
Authors: Tengku Sepora Tengku Mahadi
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Where the speed of book writing lags behind the high need for such material for tertiary studies, translation offers a way to enhance the equilibrium in this demand-supply equation. Nevertheless, translation is confronted by obstacles that threaten its effectiveness. The primary challenge to the production of efficient translations may well be related to the text-type and in terms of its complexity. A text that is intricately written with unique rhetorical devices, subject-matter foundation and cultural references will undoubtedly challenge the translator. Longer time and greater effort would be the consequence. To understand these text-related challenges, the present paper set out to analyze a lawbook entitled Learning the Law by David Melinkoff. The book is chosen because it has often been used as a textbook or for reference in many law courses in the United Kingdom and has seen over thirteen editions; therefore, it can be said to be a worthy book for studies in law. Another reason is the existence of a ready translation in Malay. Reference to this translation enables confirmation to some extent of the potential problems that might occur in its translation. Understanding the organization and the language of the book will help translators to prepare themselves better for the task. They can anticipate the research and time that may be needed to produce an effective translation. Another premise here is that this text-type implies certain ways of writing and organization. Accordingly, it seems practicable to adopt the functional theory of language as suggested by Michael Halliday as its theoretical framework. Concepts of the context of culture, the context of situation and measures of the field, tenor and mode form the instruments for analysis. Additional examples from similar materials can also be used to validate the findings. Some interesting findings include the presence of several other text-types or sub-text-types in the book and the dependence on literary discourse and devices to capture the meanings better or add color to the dry field of law. In addition, many elements of culture can be seen, for example, the use of familiar alternatives, allusions, and even terminology and references that date back to various periods of time and languages. Also found are parts which discuss origins of words and terms that may be relevant to readers within the United Kingdom but make little sense to readers of the book in other languages. In conclusion, the textual analysis in terms of its functions and the linguistic and textual devices used to achieve them can then be applied as a guide to determine the effectiveness of the translation that is produced.Keywords: functional theory of language, lawbook text-type, rhetorical devices, culture
Procedia PDF Downloads 1498541 Studies on Pre-ignition Chamber Dynamics of Solid Rockets with Different Port Geometries
Authors: S. Vivek, Sharad Sharan, R. Arvind, D. V. Praveen, J. Vigneshwar, S. Ajith, V. R. Sanal Kumar
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In this paper numerical studies have been carried out to examine the starting transient flow features of high-performance solid propellant rocket motors with different port geometries but with same propellant loading density. Numerical computations have been carried out using a 3D SST k-ω turbulence model. This code solves standard k-omega turbulence equations with shear flow corrections using a coupled second order implicit unsteady formulation. In the numerical study, a fully implicit finite volume scheme of the compressible, Reynolds-Averaged, Navier-Stokes equations are employed. We have observed from the numerical results that in solid rocket motors with highly loaded propellants having divergent port geometry the hot igniter gases can create pre-ignition thrust oscillations due to flow unsteadiness and recirculation. Under these conditions the convective flux to the surface of the propellant will be enhanced, which will create reattachment point far downstream of the transition region and it will create a situation for secondary ignition and formation of multiple-flame fronts. As a result the effective time required for the complete burning surface area to be ignited comes down drastically giving rise to a high pressurization rate (dp/dt) in the second phase of starting transient. This in effect could lead to starting thrust oscillations and eventually a hard start of the solid rocket motor. We have also observed that the igniter temperature fluctuations will be diminished rapidly and will reach the steady state value faster in the case of solid propellant rocket motors with convergent port than the divergent port irrespective of the igniter total pressure. We have concluded that the thrust oscillations and unexpected thrust spike often observed in solid rockets with non-uniform ports are presumably contributed due to the joint effects of the geometry dependent driving forces, transient burning and the chamber gas dynamics forces. We also concluded that the prudent selection of the port geometry, without altering the propellant loading density, for damping the total temperature fluctuations within the motor is a meaningful objective for the suppression and control of instability and/or pressure/thrust oscillations often observed in solid propellant rocket motors with non-uniform port geometry.Keywords: ignition transient, solid rockets, starting transient, thrust transient
Procedia PDF Downloads 4498540 CFD Effect of the Tidal Grating in Opposite Directions
Authors: N. M. Thao, I. Dolguntseva, M. Leijon
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Flow blockages referring to the increase in flow are considered as a vital equipment for marine current energy conversion. However, the shape of these devices will result in extracted energy under the operation. The present work investigates the effect of two configurations of a grating, convergent and divergent that located upstream, to the water flow velocity. Computational Fluid Dynamic simulation studies the flow characteristics by using the ANSYS Fluent solver for these specified arrangements of the grating. The results indicate that distinct features of flow velocity between “convergent” and “divergent” grating placements are up to in confined conditions. Furthermore, the velocity in case of granting is higher than that of the divergent grating.Keywords: marine current energy, converter, turbine granting, RANS simulation, water flow velocity
Procedia PDF Downloads 4098539 Early Installation Effect on the Machines’ Generated Vibration
Authors: Maitham Al-Safwani
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Motor vibration issues were analyzed by several studies. It is generally accepted that vibration issues result from poor equipment installation. We had a water injection pump tested in the factory and exceeded the pump the vibration limit. Once the pump was brought to the site, its half-size shim plates were replaced with full-size shims plates that drastically reduced the vibration. In this study, vibration data was recorded for several similar motors run at the same and different speeds. The vibration values were recorded -for two and a half hours- and the vibration readings were analyzed to determine when the readings became consistent. This was as well supported by recording the audio noises produced by some machines seeking a relationship between changes in machine noises and machine abnormalities, such as vibration.Keywords: vibration, noise, installation, machine
Procedia PDF Downloads 1838538 Numerical Investigation of Flow Past in a Staggered Tube Bundle
Authors: Kerkouri Abdelkadir
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Numerical calculations of turbulent flows are one of the most prominent modern interests in various engineering applications. Due to the difficulty of predicting, following up and studying this flow for computational fluid dynamic (CFD), in this paper, we simulated numerical study of a flow past in a staggered tube bundle, using CFD Code ANSYS FLUENT with several models of turbulence following: k-ε, k-ω and SST approaches. The flow is modeled based on the experimental studies. The predictions of mean velocities are in very good agreement with detailed LDA (Laser Doppler Anemometry) measurements performed in 8 stations along the depth of the array. The sizes of the recirculation zones behind the cylinders are also predicted. The simulations are conducted for Reynolds numbers of 12858. The Reynolds number is set to depend experimental results.Keywords: flow, tube bundle, ANSYS Fluent, CFD, turbulence, LDA, RANS (k-ε, k-ω, SST)
Procedia PDF Downloads 1648537 Digitalization, Economic Growth and Financial Sector Development in Africa
Authors: Abdul Ganiyu Iddrisu
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Digitization is the process of transforming analog material into digital form, especially for storage and use in a computer. Significant development of information and communication technology (ICT) over the past years has encouraged many researchers to investigate its contribution to promoting economic growth, and reducing poverty. Yet compelling empirical evidence on the effects of digitization on economic growth remains weak, particularly in Africa. This is because extant studies that explicitly evaluate digitization and economic growth nexus are mostly reports and desk reviews. This points out an empirical knowledge gap in the literature. Hypothetically, digitization influences financial sector development which in turn influences economic growth. Digitization has changed the financial sector and its operating environment. Obstacles to access to financing, for instance, physical distance, minimum balance requirements, low-income flows among others can be circumvented. Savings have increased, micro-savers have opened bank accounts, and banks are now able to price short-term loans. This has the potential to develop the financial sector, however, empirical evidence on digitization-financial development nexus is dearth. On the other hand, a number of studies maintained that financial sector development greatly influences growth of economies. We therefore argue that financial sector development is one of the transmission mechanisms through which digitization affects economic growth. Employing macro-country-level data from African countries and using fixed effects, random effects and Hausman-Taylor estimation approaches, this paper contributes to the literature by analysing economic growth in Africa focusing on the role of digitization, and financial sector development. First, we assess how digitization influence financial sector development in Africa. From an economic policy perspective, it is important to identify digitization determinants of financial sector development so that action can be taken to reduce the economic shocks associated with financial sector distortions. This nexus is rarely examined empirically in the literature. Secondly, we examine the effect of domestic credit to private sector and stock market capitalization as a percentage of GDP as used to proxy for financial sector development on 2 economic growth. Digitization is represented by the volume of digital/ICT equipment imported and GDP growth is used to proxy economic growth. Finally, we examine the effect of digitization on economic growth in the light of financial sector development. The following key results were found; first, digitalization propels financial sector development in Africa. Second, financial sector development enhances economic growth. Finally, contrary to our expectation, the results also indicate that digitalization conditioned on financial sector development tends to reduce economic growth in Africa. However, results of the net effects suggest that digitalization, overall, improves economic growth in Africa. We, therefore, conclude that, digitalization in Africa does not only develop the financial sector but unconditionally contributes the growth of the continent’s economies.Keywords: digitalization, economic growth, financial sector development, Africa
Procedia PDF Downloads 1038536 Unpacking the Rise of Social Entrepreneurship over Sustainable Entrepreneurship among Sri Lankan Exporters in SMEs Sector: A Case Study in Sri Lanka
Authors: Amarasinghe Shashikala, Pramudika Hansini, Fernando Tajan, Rathnayake Piyumi
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This study investigates the prominence of the social entrepreneurship (SE) model over the sustainable entrepreneurship model among Sri Lankan exporters in the small and medium enterprise (SME) sector. The primary objective of this study is to explore how the unique socio-economic contextual nuances of the country influence this behavior. The study employs a multiple-case study approach, collecting data from thirteen SEs in the SME sector. The findings reveal a significant alignment between SE and the lifestyle of the people in Sri Lanka, attributed largely to its deep-rooted religious setting and cultural norms. A crucial factor driving the prominence of SE is the predominantly labor-intensive nature of production processes within the exporters of the SME sector. These processes inherently lend themselves to SE, providing employment opportunities and fostering community engagement. Further, SE initiatives substantially resonate with community-centric practices, making them more appealing and accessible to the local populace. In contrast, the findings highlight a dilemma between cost-effectiveness and sustainable entrepreneurship. Transitioning to sustainable export products and production processes is demanded by foreign buyers and acknowledged as essential for environmental stewardship, which often requires capital-intensive makeovers. This investment inevitably raises the overall cost of the export product, making it less competitive in the global market. Interestingly, the study notes a disparity between international demand for sustainable products and the willingness of buyers to pay a premium for them. Despite the growing global preference for eco-friendly options, the findings suggest that the additional costs associated with sustainable entrepreneurship are not adequately reflected in the purchasing behavior of international buyers. The abundance of natural resources coupled with a minimal occurrence of natural catastrophes renders exporters less environmentally sensitive. The absence of robust policy support for environmental preservation exacerbates this inclination. Consequently, exporters exhibit a diminished motivation to incorporate environmental sustainability into their business decisions. Instead, attention is redirected towards factors such as the local population's minimum standards of living, prevalent social issues, governmental corruption and inefficiency, and rural poverty. These elements impel exporters to prioritize social well-being when making business decisions. Notably, the emphasis on social impact, rather than environmental impact, appears to be a generational trend, perpetuating a focus on societal aspects in the realm of business. In conclusion, the manifestation of entrepreneurial behavior within developing nations is notably contingent upon contextual nuances. This investigation contributes to a deeper understanding of the dynamics shaping the prevalence of SE over sustainable entrepreneurship among Sri Lankan exporters in the SME sector. The insights generated have implications for policymakers, industry stakeholders, and academics seeking to navigate the delicate balance between socio-cultural values, economic feasibility, and environmental sustainability in the pursuit of responsible business practices within the export sector.Keywords: small and medium enterprises, social entrepreneurship, Sri Lanka, sustainable entrepreneurship
Procedia PDF Downloads 738535 MegaProjects and the Governing Processes That Lead to Success and Failure: A Literature Review
Authors: Fangwei Zhu, Wei Tian, Linzhuo Wang, Miao Yu
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Megaproject has long been a critical issue in project governance, for its low success rate and large impact on society. Although the extant literature on megaproject governance is vast, to our best knowledge, the lacking of a thorough literature review makes it hard for us to gain a holistic view on current scenario of megaproject governance. The study conducts a systematic literature review process to analyze the existing literatures on megaproject governance. The finding indicates that mega project governance needs to be handled at network level and forming a network level governance provides a holistic framework for governing megaproject towards sustainable development of the projects. Theoretical and practical implications, as well as future studies and limitations, were discussed.Keywords: megaproject, governance, literature review, network
Procedia PDF Downloads 2008534 L2 Reading in Distance Education: Analysis of Students' Reading Attitude and Interests
Authors: Ma. Junithesmer, D. Rosales
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The study is a baseline description of students’ attitude and interests about L2 reading in a state university in the Philippines that uses distance education as a delivery mode. Most research conducted on this area dealt with the analysis of reading in a traditional school set-up. For this reason, this research was written to discover if there are implications as regards students’ preferences, interests and attitude reveal about L2 reading in a non-traditional set-up. To form the corpus of this study, it included the literature and studies about reading, preferred technological devices, titles of books and authors, reading medium traditional/ print and electronic books that juxtapose with students’ interest and feelings when reading at home and in school; and their views about their strengths and weaknesses as readers.Keywords: distance education, L2 reading, reading, reading attitude
Procedia PDF Downloads 3458533 The Study about the New Monitoring System of Signal Equipment of Railways Using Radio Communication
Authors: Masahiko Suzuki, Takashi Kato , Masahiro Kobayashi
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In our company, the monitoring system for signal equipment has already implemented. So, we can know the state of signal equipment, sitting in the control room or the maintenance center. But this system was installed over 20 years ago, so it cannot stand the needs such as 'more stable operation', 'broadband data transfer', 'easy construction and easy maintenance'. To satisfy these needs, we studied the monitoring system using radio communication as a new method which can realize the operation in the terrible environment along railroads. In these studies, we have developed the terminals and repeaters based on the ZigBee protocol and have implemented the application using two different radio bands simultaneously. At last, we got the good results from the fundamental examinations using the developed equipment.Keywords: monitoring, radio communication, 2 bands, ZigBee
Procedia PDF Downloads 5888532 Employees’ Work Performance Quality Development for Organizational Competency
Authors: Pornpong Porpraphant
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This paper aimed to demonstrate how work performance quality development activity carried out for employees in an organization could lead to the organizational success and competency as a whole. The case studies selected for this research were the Thai huge corporate including Siam Cement Group or SCG, PTT Public Company Limited, and Electricity Generating Authority of Thailand or EGAT. The in- depth interview was applied with the three main groups that included the facilitator group, the managerial group, and the operational officer group. The Plan- Do- Check- Act approach was also utilized as to build up a conceptual model in corporate management that fostered employees’ knowledge acquisition, resulting in an improved work performance.Keywords: high performance organization, quality, work performance quality development
Procedia PDF Downloads 2948531 Public Spending and Economic Growth: An Empirical Analysis of Developed Countries
Authors: Bernur Acikgoz
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The purpose of this paper is to investigate the effects of public spending on economic growth and examine the sources of economic growth in developed countries since the 1990s. This paper analyses whether public spending effect on economic growth based on Cobb-Douglas Production Function with the two econometric models with Autoregressive Distributed Lag (ARDL) and Dynamic Fixed Effect (DFE) for 21 developed countries (high-income OECD countries), over the period 1990-2013. Our models results are parallel to each other and the models support that public spending has an important role for economic growth. This result is accurate with theories and previous empirical studies.Keywords: public spending, economic growth, panel data, ARDL models
Procedia PDF Downloads 3708530 Interaction of Vegetable Fillers with Polyethylene Matrix in Biocomposites
Authors: P. V. Pantyukhov, T. V. Monakhova, A. A. Popov
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The paper studies the diffusion of low molecular weight components from vegetable fillers into polyethylene matrix during the preparation of biocomposites. In order to identify the diffusible substances a model experiment used where the hexadecane acted as a model of polyethylene. It was determined that polyphenolic compounds and chlorophyll penetrate from vegetable fillers to hexadecane to the maximum extent. There was found a correlation between the amount of polyphenolic compounds diffusible from the fillers to hexadecane and thermal oxidation kinetics of real biocomposites based on polyethylene and vegetable fillers. Thus, it has been assumed the diffusion of polyphenols and chlorophyll from vegetable fillers into polyethylene matrix during the preparation of biocomposites.Keywords: biocomposite, composite, diffusion, polyethylene, vegetable filler
Procedia PDF Downloads 446