Search results for: disaster response policy
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9193

Search results for: disaster response policy

2323 Undersea Communications Infrastructure: Risks, Opportunities, and Geopolitical Considerations

Authors: Lori W. Gordon, Karen A. Jones

Abstract:

Today’s high-speed data connectivity depends on a vast global network of infrastructure across space, air, land, and sea, with undersea cable infrastructure (UCI) serving as the primary means for intercontinental and ‘long-haul’ communications. The UCI landscape is changing and includes an increasing variety of state actors, such as the growing economies of Brazil, Russia, India, China, and South Africa. Non-state commercial actors, such as hyper-scale content providers including Google, Facebook, Microsoft, and Amazon, are also seeking to control their data and networks through significant investments in submarine cables. Active investments by both state and non-state actors will invariably influence the growth, geopolitics, and security of this sector. Beyond these hyper-scale content providers, there are new commercial satellite communication providers. These new players include traditional geosynchronous (GEO) satellites that offer broad coverage, high throughput GEO satellites offering high capacity with spot beam technology, low earth orbit (LEO) ‘mega constellations’ – global broadband services. And potential new entrants such as High Altitude Platforms (HAPS) offer low latency connectivity, LEO constellations offer high-speed optical mesh networks, i.e., ‘fiber in the sky.’ This paper focuses on understanding the role of submarine cables within the larger context of the global data commons, spanning space, terrestrial, air, and sea networks, including an analysis of national security policy and geopolitical implications. As network operators and commercial and government stakeholders plan for emerging technologies and architectures, hedging risks for future connectivity will ensure that our data backbone will be secure for years to come.

Keywords: communications, global, infrastructure, technology

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2322 Imported Oil Logistics to Central and Southern Europe Refineries

Authors: Vladimir Klepikov

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Countries of Central and Southern Europe have a typical feature: oil consumption in the region exceeds own commodity production capacity by far. So crude oil import prevails in the region’s crude oil consumption structure. Transportation using marine and pipeline transport is a common method of the imported oil delivery in the region. For certain refineries, in addition to possible transportation by oil pipelines from seaports, oil is delivered from Russian oil fields. With the view to these specific features and geographic location of the region’s refineries, three ways of imported oil delivery can be singled out: oil delivery by tankers to the port and subsequent transportation by pipeline transport of the port and the refinery; oil delivery by tanker fleet to the port and subsequent transportation by oil trunk pipeline transport; oil delivery from the fields by oil trunk pipelines to refineries. Oil is also delivered by road, internal water, and rail transport. However, the volumes transported this way are negligible in comparison to the three above transportation means. Multimodal oil transportation to refineries using the pipeline and marine transport is one of the biggest cargo flows worldwide. However, in scientific publications this problem is considered mainly for certain modes of transport. Therefore, this study is topical. To elaborate an efficient transportation policy of crude oil supply to Central and Southern Europe, in this paper the geographic concentration of oil refineries was determined and the capacities of the region’s refineries were assessed. The quantitative analysis method is used as a tool. The port infrastructure and the oil trunk pipeline system capacity were assessed in terms of delivery of raw materials to the refineries. The main groups of oil consuming countries were determined. The trends of crude oil production in the region were reviewed. The changes in production capacities and volumes at refineries in the last decade were shown. Based on the revealed refining trends, the scope of possible crude oil supplies to the refineries of the region under review was forecast. The existing transport infrastructure is able to handle the increased oil flow.

Keywords: European region, infrastructure, oil terminal capacity, pipeline capacity, refinery capacity, tanker draft

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2321 Role of Tyrosine-Phosphorylated STAT3 in Liver Regeneration: Survival, DNA Synthesis, Inflammatory Reaction and Liver Mass Recovery

Authors: JiYoung Park, SueGoo Rhee, HyunAe Woo

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In liver regeneration, quiescent hepatocytes need to be primed to fully respond to growth factors such as hepatocyte growth factor. To understand the priming process, it is necessary to analyze patterns of gene expression that occur during liver regeneration after partial hepatectomy (PHx). Recently, tyrosine phosphorylation of signal transducer and activator of transcription 3 (pYSTAT3) has been shown to play an important role in initiating liver regeneration. In order to evaluate the role of pYSTAT3 on liver regeneration after PHx, we used an intrabody which can selectively inhibit pYSTAT3. In our previous studies, an intrabody had been shown that it bound specifically to the pYSTAT3. Adenovirus-mediated expression of the intrabody in HepG2 cells, as well as mouse liver, blocked both accumulation of pYSTAT3 in the nucleus and downstream target of pYSTAT3. In this study, PHx was performed on intrabody-expressing mice and the expression levels of liver regeneration-related genes were analyzed. We also measured liver/body weight ratios and the related cellular signaling pathways were analyzed. Acute phase response genes were reduced in an intrabody-expressing mice during liver regeneration than in control virus-injected mice. However, the time course of liver mass restoration in intrabody-expressing mice was similar to that observed in control virus-injected mice. We also observed that the expression levels of anti-apoptotic genes, such as Bcl2 and Bcl-xL were decreased in intrabody-expressing mice whereas the expression of cell cycle-related genes such as cyclin D1, and c-myc was increased. Liver regeneration after PHx was partially impaired by the selective inhibition of pYSTAT3 with a phosphorylation site-specific intrabody and these results indicated that pYSTAT3 might have limited role in liver mass recovery.

Keywords: STAT3, pYSTAT3, liver regeneration, intrabody

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2320 Real-Time Monitoring of Drinking Water Quality Using Advanced Devices

Authors: Amani Abdallah, Isam Shahrour

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The quality of drinking water is a major concern of public health. The control of this quality is generally performed in the laboratory, which requires a long time. This type of control is not adapted for accidental pollution from sudden events, which can have serious consequences on population health. Therefore, it is of major interest to develop real-time innovative solutions for the detection of accidental contamination in drinking water systems This paper presents researches conducted within the SunRise Demonstrator for ‘Smart and Sustainable Cities’ with a particular focus on the supervision of the water quality. This work aims at (i) implementing a smart water system in a large water network (Campus of the University Lille1) including innovative equipment for real-time detection of abnormal events, such as those related to the contamination of drinking water and (ii) develop a numerical modeling of the contamination diffusion in the water distribution system. The first step included verification of the water quality sensors and their effectiveness on a network prototype of 50m length. This part included the evaluation of the efficiency of these sensors in the detection both bacterial and chemical contamination events in drinking water distribution systems. An on-line optical sensor integral with a laboratory-scale distribution system (LDS) was shown to respond rapidly to changes in refractive index induced by injected loads of chemical (cadmium, mercury) and biological contaminations (Escherichia coli). All injected substances were detected by the sensor; the magnitude of the response depends on the type of contaminant introduced and it is proportional to the injected substance concentration.

Keywords: distribution system, drinking water, refraction index, sensor, real-time

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2319 Reverse Logistics End of Life Products Acquisition and Sorting

Authors: Badli Shah Mohd Yusoff, Khairur Rijal Jamaludin, Rozetta Dollah

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The emerging of reverse logistics and product recovery management is an important concept in reconciling economic and environmental objectives through recapturing values of the end of life product returns. End of life products contains valuable modules, parts, residues and materials that can create value if recovered efficiently. The main objective of this study is to explore and develop a model to recover as much of the economic value as reasonably possible to find the optimality of return acquisition and sorting to meet demand and maximize profits over time. In this study, the benefits that can be obtained for remanufacturer is to develop demand forecasting of used products in the future with uncertainty of returns and quality of products. Formulated based on a generic disassembly tree, the proposed model focused on three reverse logistics activity, namely refurbish, remanufacture and disposal incorporating all plausible means quality levels of the returns. While stricter sorting policy, constitute to the decrease amount of products to be refurbished or remanufactured and increases the level of discarded products. Numerical experiments carried out to investigate the characteristics and behaviour of the proposed model with mathematical programming model using Lingo 16.0 for medium-term planning of return acquisition, disassembly (refurbish or remanufacture) and disposal activities. Moreover, the model seeks an analysis a number of decisions relating to trade off management system to maximize revenue from the collection of use products reverse logistics services through refurbish and remanufacture recovery options. The results showed that full utilization in the sorting process leads the system to obtain less quantity from acquisition with minimal overall cost. Further, sensitivity analysis provides a range of possible scenarios to consider in optimizing the overall cost of refurbished and remanufactured products.

Keywords: core acquisition, end of life, reverse logistics, quality uncertainty

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2318 Media-Based Interventions to Influence English Language Learning: A Case of Bangladesh

Authors: Md. Mizanoor Rahman, Md. Zakir Hossain Talukder, M. Mahruf C. Shohel, Prithvi Shrestha

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In Bangladesh, classroom practice and English Learning (EL) competencies acquired both by the teacher and learner in primary and secondary schools are still very weak. Therefore, English is the most commonly failed examination subject at the school level; in addition, there are severe problems in communicative English by the Bangladeshi nationals– this has been characterized as a constraint to economic development. Job applicants and employees often lack English language skills necessary to work effectively. As a result; both government and its international development partners such as DFID, UNESCO, and CIDA have been very active to uplift the quality of the English language learning and implementing projects with innovative approaches. Recently; the economy has been increasing and in line with this, the technology has been deployed in English learning to improve reading, writing, speaking and listening skills. Young Bangladeshi creative, from a variety of backgrounds including film, animation, photography, and digital media are being trained to develop ideas for English Language Teaching (ELT) media. They are being motivated to develop a wide range of ideas for low cost English learning media products. English Language education policy in Bangladesh supports communicative language teaching practices and accordingly, actors have been influencing curriculum, textbook, deployment of technology and assessment changes supporting communicative ELT. The various projects are also being implemented to reform the curriculum, revise the textbook and adjust the assessment mechanism so that the country can increase in proficiency in communicative English among the population. At present; the numbers of teachers, students and adult learners classified at higher levels of proficiency because of deployment of technology and motivation for learning and using English among school population of Bangladesh. The current paper discusses the various interventions in Bangladesh with appropriate media to improve the competencies of the ELT among population.

Keywords: English learning, technology, education, psychological sciences

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2317 Sick Minds and Social Media: Treacherous Trends in Online Stalking, Aggression, and Murder

Authors: Amanda Maitland

Abstract:

This preliminary study has examined ways in which social media may help cause stalker murder by individuals with personality disorders and a strong sense of sexual propriety. A public display on social media by the intended victim was felt to be a trigger that instigated interpersonal violence. To identify behavioural paradigms, case studies of intimate partner murders were explored using news media sources and documentaries. In all of the case studies, social media interaction and social media postings occurred shortly before the murder. The evidence suggested a preponderance of correlations between the social media postings, stalking behaviours, personality disorders, and the murder of an intimate partner. In addition to this, a profile for of Facebook/social media murder was gleaned from the paradigms of behavior found in the case studies. The evidence showed a complex relationship between severe violence, stalking, borderline personality, and intimate partner violence was identified through the study. The struggle clients have in dealing with the: public, ambiguous and unrelenting nature of social media postings was also observed. The murderers anguish and rage appeared to be further intensified by attitudes of sexual propriety and entitlement. These attitudes were evident in all the case studies. The study concluded with further research on how the public can protect themselves from entering situations where social media postings might trigger a violent response. Further to this, psychological approaches were identified that might support client’s with personality disorders to cope with perceived provocative and distressing data on the internet. Thus, the findings of this study will be of interest to: therapists, psychologists, nurses, criminologists and social workers.

Keywords: social media, borderline personality, murder, cyberstalking, intimate partner violence, sexual propriety, Facebook

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2316 The Impact of Australia's Skilled Migrant Selection System: A Case Study of Japanese Skilled Migrants and Their Families

Authors: Iori Hamada

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Australia's skilled migrant selection system is constantly changing its target skills and criteria according to the labour market demands. The government's intention to employ this highly selective market-driven selection system is to better target the skills needed in the economy, enable skilled migrants to be employed in industries that have the highest need, and consequently boost the economy and population. However, migration scholars have called this intention into question, arguing that the system is not making the best use of skilled migrants. This paper investigates the impact of recent reforms in Australian skilled migration system on skilled migrants' employment and related life conditions. Drawing on semi-structured qualitative interviews with Japanese skilled migrants in Australia, it argues that Australia’s skilled migrant selection system guarantees neither skilled migrants' employment nor successful transfer of their skills to the labour market. The findings show that Japanese skilled migrants are often unemployed or under-employed, although they intend to achieve upward occupational mobility. The interview data also reveal that male unemployment or under-employment status prompts some Japanese men to leave Australia and find a job that better matches their skills and qualifications in a new destination. Further, it finds that Japanese male skilled migrants who experience downward occupational mobility tend to continue to take a primary breadwinner role, which affects the distribution of paid and unpaid work within their families. There is a growing body of research investigating skilled migrants’ downward career mobility. However, little has been written on skilled Japanese migrants. Further, the work-family intersection is a 'hot public policy topic' in Australia and elsewhere. Yet, the existing studies focus almost exclusively on non-migrant families. This calls attention to the urgency of assessing the work-family lives of skilled migrants. This study fills these gaps, presenting additional insight into Japanese skilled migrants’ work and family in and beyond Australia.

Keywords: Australia, employment, family, Japanese skilled migrants

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2315 Non Enzymatic Electrochemical Sensing of Glucose Using Manganese Doped Nickel Oxide Nanoparticles Decorated Carbon Nanotubes

Authors: Anju Joshi, C. N. Tharamani

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Diabetes is one of the leading cause of death at present and remains an important concern as the prevalence of the disease is increasing at an alarming rate. Therefore, it is crucial to diagnose the accurate levels of glucose for developing an efficient therapeutic for diabetes. Due to the availability of convenient and compact self-testing, continuous monitoring of glucose is feasible nowadays. Enzyme based electrochemical sensing of glucose is quite popular because of its high selectivity but suffers from drawbacks like complicated purification and immobilization procedures, denaturation, high cost, and low sensitivity due to indirect electron transfer. Hence, designing a robust enzyme free platform using transition metal oxides remains crucial for the efficient and sensitive determination of glucose. In the present work, manganese doped nickel oxide nanoparticles (Mn-NiO) has been synthesized onto the surface of multiwalled carbon nanotubes using a simple microwave assisted approach for non-enzymatic electrochemical sensing of glucose. The morphology and structure of the synthesized nanostructures were characterized using scanning electron microscopy (SEM) and X-Ray diffraction (XRD). We demonstrate that the synthesized nanostructures show enormous potential for electrocatalytic oxidation of glucose with high sensitivity and selectivity. Cyclic voltammetry and square wave voltammetry studies suggest superior sensitivity and selectivity of Mn-NiO decorated carbon nanotubes towards the non-enzymatic determination of glucose. A linear response between the peak current and the concentration of glucose has been found to be in the concentration range of 0.01 μM- 10000 μM which suggests the potential efficacy of Mn-NiO decorated carbon nanotubes for sensitive determination of glucose.

Keywords: diabetes, glucose, Mn-NiO decorated carbon nanotubes, non-enzymatic

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2314 The Extent of Land Use Externalities in the Fringe of Jakarta Metropolitan: An Application of Spatial Panel Dynamic Land Value Model

Authors: Rahma Fitriani, Eni Sumarminingsih, Suci Astutik

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In a fast growing region, conversion of agricultural lands which are surrounded by some new development sites will occur sooner than expected. This phenomenon has been experienced by many regions in Indonesia, especially the fringe of Jakarta (BoDeTaBek). Being Indonesia’s capital city, rapid conversion of land in this area is an unavoidable process. The land conversion expands spatially into the fringe regions, which were initially dominated by agricultural land or conservation sites. Without proper control or growth management, this activity will invite greater costs than benefits. The current land use is the use which maximizes its value. In order to maintain land for agricultural activity or conservation, some efforts are needed to keep the land value of this activity as high as possible. In this case, the knowledge regarding the functional relationship between land value and its driving forces is necessary. In a fast growing region, development externalities are the assumed dominant driving force. Land value is the product of the past decision of its use leading to its value. It is also affected by the local characteristics and the observed surrounded land use (externalities) from the previous period. The effect of each factor on land value has dynamic and spatial virtues; an empirical spatial dynamic land value model will be more useful to capture them. The model will be useful to test and to estimate the extent of land use externalities on land value in the short run as well as in the long run. It serves as a basis to formulate an effective urban growth management’s policy. This study will apply the model to the case of land value in the fringe of Jakarta Metropolitan. The model will be used further to predict the effect of externalities on land value, in the form of prediction map. For the case of Jakarta’s fringe, there is some evidence about the significance of neighborhood urban activity – negative externalities, the previous land value and local accessibility on land value. The effects are accumulated dynamically over years, but they will fully affect the land value after six years.

Keywords: growth management, land use externalities, land value, spatial panel dynamic

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2313 Developing a Research Culture in the Faculty of Engineering and Information Technology at the Central University of Technology, Free State: Implications for Knowledge Management

Authors: Mpho Agnes Mbeo, Patient Rambe

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The thirteenth year of the Central University of Technology, Free State’s (CUT) transition from a vocational and professional training orientation institution (i.e. a technikon) into a university with a strong research focus has neither been a smooth nor an easy one. At the heart of this transition was the need to transform the psychological faculties of academic and research staffs compliment who were accustomed to training graduates for industrial placement. The lack of a culture of research that fully embraces a strong ethos of conducting world-class research needed to be addressed. The induction and socialisation of academic staff into the development and execution of cutting-edge research also required the provision of research support and the creation of a conducive academic environment for research, both for emerging and non-research active academics. Drawing on ten cases, comprising four heads of departments, three prolific established researchers, and three emerging researchers, this study explores the challenges faced in establishing a strong research culture at the university. Furthermore, it gives an account of the extent to which the current research interventions have addressed the perceivably “missing research culture”, and the implications of these interventions for knowledge management. Evidence suggests that the endowment of an ideal institutional research environment (comprising strong internet networks, persistent connectivity on and off campus), research peer mentorship, and growing publication outputs should be matched by a coherent research incentive culture and strong research leadership. This is critical to building new knowledge and entrenching knowledge management founded on communities of practice and scholarly networking through the documentation and communication of research findings. The study concludes that the multiple policy documents set for the different domains of research may be creating pressure on researchers to engage research activities and increase output at the expense of research quality.

Keywords: Central University of Technology, performance, publication, research culture, university

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2312 Enhancing Digi-Parenting Strategies to Mitigate Children’s Cyber-Aggression

Authors: Misha Teimouri

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Our world has been transformed by the use of the internet and the constant flow of information. While this transmission has its benefits, it has also added significant challenges to family relations, primarily in the field of parenting and children's digital lives. Screens, speed, and connectedness are the words that characterize the lives of today's digital generation; it's as if the entire world is in their pockets at all times. Parents attempt to regulate and control their children's internet use in the hopes of maximizing the advantages and minimizing the disadvantages of their children's internet use; however, given that children spend more time online, particularly ever since the pandemic, children's cyber-aggression has become an issue for them. Children may externalize their behavior online, bully others, send anger/hatred/resist messages, share violent and bloody content, and engage in sexting. These types of online aggression make parenting more difficult, especially for digital immigrant parents compared to digital native parents. In response to these challenges, this study investigated the level of cyber aggression among children, as well as the effects of digi-parenting (active, monitoring, restrictive, and warm and supportive) on children's cyber-aggression (sexual, verbal, visual) as victims or aggressors. The study also determined whether there were any differences in parenting styles between digital natives (DN) and digital immigrants. In accordance with the study, boys and older children are more likely to engage in cyber aggression as aggressors, whereas girls and younger children are more likely to engage as victims. Warmth and supportive digiparenting have a greater impact on children's cyber-aggression (sexual, verbal, and visual) as victims or aggressors. This study also found that, when compared to DI parents, DN parents are more successful at digi-parenting and reducing their children's exposure to cyber-aggression.

Keywords: digi-parenting, cyber-aggression, digital natives, digital immigrants, children's cyber-aggression (sexual, verbal, visual)

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2311 The Essence and Attribution of Intellectual Property Rights Generated in the Digitization of Intangible Cultural Heritage

Authors: Jiarong Zhang

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Digitizing intangible cultural heritage is a complex and comprehensive process from which sorts of intellectual property rights may be generated. Digitizing may be a repacking process of cultural heritage, which creates copyrights; recording folk songs and indigenous performances can create 'related rights'. At the same time, digitizing intangible cultural heritage may infringe the intellectual property rights of others unintentionally. Recording religious rituals of indigenous communities without authorization can violate the moral right of the ceremony participants of the community; making digital copies of rock paintings may infringe the right of reproduction. In addition, several parties are involved in the digitization process: indigenous peoples, museums, and archives can be holders of cultural heritage; companies and research institutions can be technology providers; internet platforms can be promoters and sellers; the public and groups above can be beneficiaries. When diverse intellectual property rights versus various parties, problems and disputes can arise easily. What are the types of intellectual property rights generated in the digitization process? What is the essence of these rights? Who should these rights belong to? How to use intellectual property to protect the digitalization of cultural heritage? How to avoid infringing on the intellectual property rights of others? While the digitization has been regarded as an effective approach to preserve intangible cultural heritage, related intellectual property issues have not received the attention and full discussion. Thus, parties involving in the digitization process may face intellectual property infringement lawsuits. The article will explore those problems from the intersection perspective of intellectual property law and cultural heritage. From a comparative approach, the paper will analysis related legal documents and cases, and shed some lights of those questions listed. The findings show, although there are no intellectual property laws targeting the cultural heritage in most countries, the involved stakeholders can seek protection from existing intellectual property rights following the suggestions of the article. The research will contribute to the digitization of intangible cultural heritage from a legal and policy aspect.

Keywords: copyright, digitization, intangible cultural heritage, intellectual property, Internet platforms

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2310 Raising Forest Voices: A Cross-Country Comparative Study of Indigenous Peoples’ Engagement with Grassroots Climate Change Mitigation Projects in the Initial Pilot Phase of Community-Based Reducing Emissions from Deforestation and forest Degradation

Authors: Karl D. Humm

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The United Nations’ Community-based REDD+ (Reducing Emissions from Deforestation and forest Degradation) (CBR+) is a programme that directly finances grassroots climate change mitigation strategies that uplift Indigenous Peoples (IPs) and other marginalised groups. A pilot for it in six countries was developed in response to criticism of the REDD+ programme for excluding IPs from dialogues about climate change mitigation strategies affecting their lands and livelihoods. Despite the pilot’s conclusion in 2017, no complete report has yet been produced on the results of CBR+. To fill this gap, this study investigated the experiences with involving IPs in the CBR+ programmes and local projects across all six pilot countries. A literature review of official UN reports and academic articles identified challenges and successes with IP participation in REDD+ which became the basis for a framework guiding data collection. A mixed methods approach was used to collect and analyse qualitative and quantitative data from CBR+ documents and written interviews with CBR+ National Coordinators in each country for a cross-country comparative analysis. The study found that the most frequent challenges were lack of organisational capacity, illegal forest activities, and historically-based contentious relationships in IP and forest-dependent communities. Successful programmes included IPs and incorporated respect and recognition of IPs as major stakeholders in managing sustainable forests. Findings are summarized and shared with a set of recommendations for improvement of future projects.

Keywords: climate change, forests, indigenous peoples, REDD+

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2309 Optimal Power Distribution and Power Trading Control among Loads in a Smart Grid Operated Industry

Authors: Vivek Upadhayay, Siddharth Deshmukh

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In recent years utilization of renewable energy sources has increased majorly because of the increase in global warming concerns. Organization these days are generally operated by Micro grid or smart grid on a small level. Power optimization and optimal load tripping is possible in a smart grid based industry. In any plant or industry loads can be divided into different categories based on their importance to the plant and power requirement pattern in the working days. Coming up with an idea to divide loads in different such categories and providing different power management algorithm to each category of load can reduce the power cost and can come handy in balancing stability and reliability of power. An objective function is defined which is subjected to a variable that we are supposed to minimize. Constraint equations are formed taking difference between the power usages pattern of present day and same day of previous week. By considering the objectives of minimal load tripping and optimal power distribution the proposed problem formulation is a multi-object optimization problem. Through normalization of each objective function, the multi-objective optimization is transformed to single-objective optimization. As a result we are getting the optimized values of power required to each load for present day by use of the past values of the required power for the same day of last week. It is quite a demand response scheduling of power. These minimized values then will be distributed to each load through an algorithm used to optimize the power distribution at a greater depth. In case of power storage exceeding the power requirement, profit can be made by selling exceeding power to the main grid.

Keywords: power flow optimization, power trading enhancement, smart grid, multi-object optimization

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2308 Solar-Blind Ni-Schottky Photodetector Based on MOCVD Grown ZnGa₂O₄

Authors: Taslim Khan, Ray Hua Horng, Rajendra Singh

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This study presents a comprehensive analysis of the design, fabrication, and performance evaluation of a solar-blind Schottky photodetector based on ZnGa₂O₄ grown via MOCVD, utilizing Ni/Au as the Schottky electrode. ZnGa₂O₄, with its wide bandgap of 5.2 eV, is well-suited for high-performance solar-blind photodetection applications. The photodetector demonstrates an impressive responsivity of 280 A/W, indicating its exceptional sensitivity within the solar-blind ultraviolet band. One of the device's notable attributes is its high rejection ratio of 10⁵, which effectively filters out unwanted background signals, enhancing its reliability in various environments. The photodetector also boasts a photodetector responsivity contrast ratio (PDCR) of 10⁷, showcasing its ability to detect even minor changes in incident UV light. Additionally, the device features an outstanding detective of 10¹⁸ Jones, underscoring its capability to precisely detect faint UV signals. It exhibits a fast response time of 80 ms and an ON/OFF ratio of 10⁵, making it suitable for real-time UV sensing applications. The noise-equivalent power (NEP) of 10^-17 W/Hz further highlights its efficiency in detecting low-intensity UV signals. The photodetector also achieves a high forward-to-backward current rejection ratio of 10⁶, ensuring high selectivity. Furthermore, the device maintains an extremely low dark current of approximately 0.1 pA. These findings position the ZnGa₂O₄-based Schottky photodetector as a leading candidate for solar-blind UV detection applications. It offers a compelling combination of sensitivity, selectivity, and operational efficiency, making it a highly promising tool for environments requiring precise and reliable UV detection.

Keywords: wideband gap, solar blind photodetector, MOCVD, zinc gallate

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2307 Structural Damage Detection Using Modal Data Employing Teaching Learning Based Optimization

Authors: Subhajit Das, Nirjhar Dhang

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Structural damage detection is a challenging work in the field of structural health monitoring (SHM). The damage detection methods mainly focused on the determination of the location and severity of the damage. Model updating is a well known method to locate and quantify the damage. In this method, an error function is defined in terms of difference between the signal measured from ‘experiment’ and signal obtained from undamaged finite element model. This error function is minimised with a proper algorithm, and the finite element model is updated accordingly to match the measured response. Thus, the damage location and severity can be identified from the updated model. In this paper, an error function is defined in terms of modal data viz. frequencies and modal assurance criteria (MAC). MAC is derived from Eigen vectors. This error function is minimized by teaching-learning-based optimization (TLBO) algorithm, and the finite element model is updated accordingly to locate and quantify the damage. Damage is introduced in the model by reduction of stiffness of the structural member. The ‘experimental’ data is simulated by the finite element modelling. The error due to experimental measurement is introduced in the synthetic ‘experimental’ data by adding random noise, which follows Gaussian distribution. The efficiency and robustness of this method are explained through three examples e.g., one truss, one beam and one frame problem. The result shows that TLBO algorithm is efficient to detect the damage location as well as the severity of damage using modal data.

Keywords: damage detection, finite element model updating, modal assurance criteria, structural health monitoring, teaching learning based optimization

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2306 On-Farm Research on Organic Fruits Production in the Eastern Thailand

Authors: Sali Chinsathit, Haruthai Kaenla

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Organic agriculture has become a major policy theme for agricultural development in Thailand since October 2005. Organic farming is enlisted as an important national agenda, to promote safe food and national export, and many government authorities have initiated projects and activities centered on organic farming promotion. Currently, Thailand has the market share of about 32 million US$ a year by exporting organic products of rice, vegetables, tea, fruits and a few medicinal herbs. There is high potential in organic crop production as there is the tropical environment promoting crop growth and leader farmer in organic farming. However, organic sector is relatively small (0.2%) comparing with conventional agricultural area, since there are many factors affecting farmers’ adoption and success in organic farming. The objective of this project was to get the organic production technology for at least 3 organic crops. The treatment and method were complied with Thai Organic Standard, and were mainly concerned on increase plant biodiversity and soil improvement by using organic fertilizer and bio-extract from fish, egg, plant and fruits. The bio-logical control, plant-extracts, and cultural practices were used to control insect pests and diseases of 3 crops including mangosteen (Garcinia mangostana L.), longkong (Aglaia dookoo Griff.) and banana (Musa (AA group)). The experiments were carried out at research centers of Department of Agriculture and farmers’ farms in Rayong and Chanthaburi provinces from 2009 to 2013. We found that both locations, plant biodiversity by intercropping mangosteen or longkong with banana and soil improvement with composts and bio-extract from fish could increased yield and farmers’ income by 6,835 US$/ha/year. Farmers got knowledge from these technologies to produce organic crops. The organic products were sold both in domestic and international countries. The organic production technologies were also environmental friendly and could be used as an alternative way for farmers in Thailand.

Keywords: banana, longkong, mangosteen, organic farming

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2305 Impact of Covid-19 on Digital Transformation

Authors: Tebogo Sethibe, Jabulile Mabuza

Abstract:

The COVID-19 pandemic has been commonly referred to as a ‘black swan event’; it has changed the world, from how people live, learn, work and socialise. It is believed that the pandemic has fast-tracked the adoption of technology in many organisations to ensure business continuity and business sustainability; broadly said, the pandemic has fast-tracked digital transformation (DT) in different organisations. This paper aims to study the impact of the COVID-19 pandemic on DT in organisations in South Africa by focusing on the changes in IT capabilities in the DT framework. The research design is qualitative. The data collection was through semi-structured interviews with information communication technology (ICT) leaders representing different organisations in South Africa. The data were analysed using the thematic analysis process. The results from the study show that, in terms of ICT in the organisation, the pandemic had a direct and positive impact on ICT strategy and ICT operations. In terms of IT capability transformation, the pandemic resulted in the optimisation and expansion of existing IT capabilities in the organisation and the building of new IT capabilities to meet emerging business needs. In terms of the focus of activities during the pandemic, there seems to be a split in organisations between the primary focus being on ‘digital IT’ or ‘traditional IT’. Overall, the findings of the study show that the pandemic had a positive and significant impact on DT in organisations. However, a definitive conclusion on this would require expanding the scope of the research to all the components of a comprehensive DT framework. This study is significant because it is one of the first studies to investigate the impact of the COVID-19 pandemic on organisations, on ICT in the organisation, on IT capability transformation and, to a greater extent, DT. The findings from the study show that in response to the pandemic, there is a need for: (i) agility in organisations; (ii) organisations to execute on their existing strategy; (iii) the future-proofing of IT capabilities; (iv) the adoption of a hybrid working model; and for (v) organisations to take risks and embrace new ideas.

Keywords: digital transformation, COVID-19, bimodal-IT, digital transformation framework

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2304 Retrospective/Prospective Analysis of Guideline Implementation and Transfusion Rates

Authors: B. Kenny

Abstract:

The complications associated with transfusions are well documented, with the serious hazards of transfusion (SHOT) reporting system continuing to report deaths and serious morbidity due to the transfusion of allogenic blood. Many different sources including the TRICC trial, NHMRC and Cochrane recommending similar transfusion triggers/guidelines. Recent studies found the rate of infection (deep infection, wound infection, chest infection, urinary tract infection, and others) were purely a dose response relationship, increasing the Relative Risk by 3.44. It was also noted that each transfused patient stayed in hospital for one additional day. We hypothesise that providing an approved/standardised, guideline with a graphical summary of decision pathways for anaemic patients will reduce unnecessary transfusions. We retrospectively assessed patients undergoing primary knee or hip arthroplasties over a 4 year period, 1459 patients. Of these, 339 (23.24%) patients received allogenic blood transfusions and 858 units of blood were transfused, 9.14% of patients transfused had haemoglobin levels above 100 g/L, 7.67% of patients were transfused without knowing the haemoglobin level, 24 hours prior to transfusion initiation and 4.5% had possible transfusion reactions. Overall, 17% of allogenic transfusions topatients admitted to the Orthopaedic department within a 4 year period were outside NHMRC and Cochrane guidelines/recommendations. If our transfusion frequency is compared with that of other authors/hospitals, transfusion rates are consistently being high. We subsequently implemented a simple guideline for transfusion initiation. This guideline was then assessed. We found the transfusion rate post transfusion implementation to be significantly lower, without increase in patient morbidity or mortalitiy, p <0.001). Transfusion rates and patient outcome can be optimized by a simple graphical aid for decision making.

Keywords: transfusion, morbidity, mortality, neck of femur, fracture, arthroplasty, rehabilitation

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2303 Analysis of the Advent of Multinational Corporations in Developing Countries: Case Study of Nike Factories Expansion in Vietnam

Authors: Khue Do Phan

Abstract:

Nike has been confronted by the press with their harsh working conditions, underpayment and highly-labor intensive requirement to their manufacturing workers and hiring of underage workers in Vietnam, Nike's largest production center. To analyze this topic critically through an international relations perspective, theory of dependency will be used to criticize the notion of exploitation of resources from developed countries towards developing countries. Theory of economic liberalism will be used to support the notion private property, the free market and generally capitalism as beneficial to both developing and developed countries. Workers are mentally, physically and sexually abused in the factories. In addition to this, their working conditions consist of improper training, lack of safety equipment, exposure of chemicals (glues and pants), their average wage is below the minimum wage in their country; the workers have to work around 60 hours or more a week. Even Nike says that the conditions are regulated often to make sure the workers get a voice to have their work rights and safe working environment. The monitors come to analyze the factories but in the end talk to the employers, whom are the direct abusers to the employees. Health benefits are rarely granted to the employees; they are forced to pay their bills first then the company will reimburse them later. They would also get in trouble for using the bathroom, taking a lunch break or sick days off because this would mean it would decrease their hours of work, leading to an even lower wage and a really angry employer. Of course with the press criticizing Nike’s lack of respect for human rights and working rights, Nike has been working on policy making and implementation to deal with the abuses. Due to its large chains and a great number of outsourcing host countries, the changes that Nike wish or attempt to make have not be in effect as quickly nor spreading to all countries it holds accountable for in its outsourcing factories.

Keywords: dependency theory, economic liberalism, human rights, outsource

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2302 Understanding the Influence of Cross-National Distances on Tourist Expenditure

Authors: Wei-Ting Hung

Abstract:

Inbound tourist expenditure might not only have influenced by individual tourist characteristics but may also be affected by nationality characteristics. The cross national distance effects on tourist consumption behavior should be incorporated in the analytical framework. Additionally, the often used factor analysis, cluster analysis and regression analysis overlook the hierarchical tourist consumption data structure and may lead to misleading results. The objectives of the present study were twofold. First, we propose a multilevel model that takes individual and cross-national differences into account under a hierarchical framework. Second, we further sought to determine the types of cross-national differences affecting tourist expenditure. Thus, this study incorporates the individual tourist effects and cross national distance effects simultaneously, uses the data of 2010 Annual Survey Report on Visitors’ Expenditure and Trends in Taiwan to investigate the determinants of inbound tourist expenditure. Multilevel analysis was used to investigate the influence of individual tourist effects and cross national distance effects on inbound tourist expenditure. The empirical results show that cross national distance plays a crucial role in tourist consumption behavior. Our findings also indicate age and income have positive influence on tourism expenditure., whereas education and gender do not have significant impact. Regarding macro-level factors, geographic and cultural differences exhibited significant positive relationships on tourism expenditure, while economic differences did not. Based on the above empirical results, it is suggested that tour operators should take tourists’ individual attributes, particularly their income and age, into consideration when arranging tours. In addition, nationality holds sway over tourists’ consumption behavior, of which geographic and cultural differences are the two major factors at play. The empirical results of this study serve as practical suggestions for tourism marketing strategies and policy implications for government policies.

Keywords: cross national distance, inbound tourist, multilevel analysis, tourist expenditure

Procedia PDF Downloads 354
2301 Quantifying Wave Attenuation over an Eroding Marsh through Numerical Modeling

Authors: Donald G. Danmeier, Gian Marco Pizzo, Matthew Brennan

Abstract:

Although wetlands have been proposed as a green alternative to manage coastal flood hazards because of their capacity to adapt to sea level rise and provision of multiple ecological and social co-benefits, they are often overlooked due to challenges in quantifying the uncertainty and naturally, variability of these systems. This objective of this study was to quantify wave attenuation provided by a natural marsh surrounding a large oil refinery along the US Gulf Coast that has experienced steady erosion along the shoreward edge. The vegetation module of the SWAN was activated and coupled with a hydrodynamic model (DELFT3D) to capture two-way interactions between the changing water level and wavefield over the course of a storm event. Since the marsh response to relative sea level rise is difficult to predict, a range of future marsh morphologies is explored. Numerical results were examined to determine the amount of wave attenuation as a function of marsh extent and the relative contributions from white-capping, depth-limited wave breaking, bottom friction, and flexing of vegetation. In addition to the coupled DELFT3D-SWAN modeling of a storm event, an uncoupled SWAN-VEG model was applied to a simplified bathymetry to explore a larger experimental design space. The wave modeling revealed that the rate of wave attenuation reduces for higher surge but was still significant over a wide range of water levels and outboard wave heights. The results also provide insights to the minimum marsh extent required to fully realize the potential wave attenuation so the changing coastal hazards can be managed.

Keywords: green infrastructure, wave attenuation, wave modeling, wetland

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2300 Sports Preferente Intervention as a Predictor of Sustainable Participation at Risk Teenagers in Ibadan Metropolis, Ibadan Nigerian

Authors: Felix Olajide Ibikunle

Abstract:

Introductory Statement: Sustainable participation of teenagers in sport requires deliberate and concerted plan and managerial policy rooted in the “philosophy of catch them young”. At risk, teenagers need proper integration into societal aspiration: This direction will go a long way to streamline them into the security breach and attractive nuisance free lifestyles. Basic Methodology: The population consists of children within 13-19 years old. A proportionate sampling size technique of 60% was adopted to select seven zones out of 11 geo-political zones in the Ibadan metropolis. Qualitative information and interview were used to collect needed information. Majority of the teenagers were out of school, street hawkers, motor pack, touts, and unserious vocation apprentices. These groups have the potentials of security breaches in the metropolis and beyond. Five hundred and thirty-four (534) respondents were used for the study. They were drawn from Ojoo, Akingbile, and Moniya axis = 72, Agbowo, Ajibode, and Apete axis = 74; Akobo, Basorun, and Idi-ape axis 79; Wofun, Monatan, and Iyana-Church axis = 78; Molete, Oke-ado and Oke-Bola axis = 75; Beere, Odinjo, Elekuro axis = 77; Eleyele, Ologuneru, and Alesinloye axis = 79. Major Findings: Multiple regression was used to analyze the independent variables and percentage. The respondents average age was 15.6 years old, and with 100% male. The instrument(questionnaire) used yielded; sport preference (r = 0.72); intervention (r = 0.68) and the sustainable participation (r = 0.70).The relative contributions of sport preference on participation of at risk teenagers was (F-ratio = 1.067); Intervention contribution of sport on participation of at risk teenagers = produced (F-ratio of 12.095) was significant while sustainable participation of at risk teenager produced (F-ratio = 1.062) was significant. Closing Statement: The respondents’ sport preference stimulated their participation in sport. The intervention exposed at risk-teenagers to coaching, which activated their interest and participation in sport. While sustainable participation contributed positively to evolve at risk teenagers participation in their preferred sport.

Keywords: sport, preference, intervention, teenagers, sustainable, participation and risk teenagers

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2299 Exploring the Impact of Cultural Values on the Performance of Women Bureaucrats in Pakistan

Authors: Fariya Tahreen

Abstract:

Women are an important part of the society comprising more than 50% population of the world. Participation of women in public services is increasing in the present era while cultural values embedded with gender differences still influencing the performance of working women. Many researches have been carried out on cultural impact on working women like managers, doctors, and lawyers and other public servants. But very rare efforts were made to study the impact of cultural values on the performance of women bureaucrats. The present study aimed to find out the relationship of cultural values (i.e., collective identity, gender segregation, and gender asymmetrical relations) with the performance of women bureaucrats. Sample of the present study comprised of 130 women bureaucrats from the Office Management Group, Inland Revenue, District Management Group, and Pakistan Police Services which is selected by convenient sampling technique. The locale of the study was Islamabad, Rawalpindi and Lahore city. The current research study was conducted by using a quantitative approach in research method and data were collected through survey method. The measures used in the study included: personal information, three main cultural values, and performance of women bureaucrats. Uni-variate and bi-variate analyses were implied by using correlation and multiple linear regression test. The current study shows a negative significant relationship between cultural values and performance of women bureaucrats (R²= 0.790, p-value 0.000). It shows that cultural values (collective identity, gender segregation and gender asymmetrical relations) significantly influence the performance of women bureaucrats. Due to the influence and pressure of these cultural values, women bureaucrats give less time to the office and avail more leaves. They also avoid contacting with male colleagues, public dealings, field visits and playing leadership role. Further, they attend fewer meetings of policy formulation due to given less importance for it. In a nutshell, the study concluded that cultural values significantly influence the performance of women bureaucrats in Pakistan.

Keywords: cultural values, performance, Pakistan, women bureaucrats

Procedia PDF Downloads 122
2298 Impact of Output Market Participation on Cassava-Based Farming Households' Welfare in Nigeria

Authors: Seyi Olalekan Olawuyi, Abbyssiania Mushunje

Abstract:

The potential benefits of agricultural production to improve the welfare condition of smallholder farmers in developing countries is no more a news because it has been widely documented. Yet majority of these farming households suffer from shortfall in production output to meet both the consumption needs and market demand which adversely affects output market participation and by extension welfare condition. Therefore, this study investigated the impacts of output market participation on households’ welfare of cassava-based farmers in Oyo State, Nigeria. Multistage sampling technique was used to select 324 sample size used for this study. The findings from the data obtained and analyzed through composite score and crosstab analysis revealed that there is varying degree of output market participation among the farmers which also translate to the observed welfare profile differentials in the study area. The probit model analysis with respect to the selection equation identified gender of household head, household size, access to remittance, off-farm income and ownership of farmland as significant drivers of output market participation in the study area. Furthermore, the treatment effect model of the welfare equation and propensity score matching (PSM) technique were used as robust checks; and the findings attest to the fact that, complimentarily with other significant variables highlighted in this study, output market participation indeed has a significant impact on farming households’ welfare. As policy implication inferences, the study recommends female active inclusiveness and empowerment in farming activities, birth control strategies, secondary income smoothing activities and discouragement of land fragmentation habits, to boost productivity and output market participation, which by extension can significantly improve farming households’ welfare.

Keywords: Cassava market participation, households' welfare, propensity score matching, treatment effect model

Procedia PDF Downloads 155
2297 Application of Single Tuned Passive Filters in Distribution Networks at the Point of Common Coupling

Authors: M. Almutairi, S. Hadjiloucas

Abstract:

The harmonic distortion of voltage is important in relation to power quality due to the interaction between the large diffusion of non-linear and time-varying single-phase and three-phase loads with power supply systems. However, harmonic distortion levels can be reduced by improving the design of polluting loads or by applying arrangements and adding filters. The application of passive filters is an effective solution that can be used to achieve harmonic mitigation mainly because filters offer high efficiency, simplicity, and are economical. Additionally, possible different frequency response characteristics can work to achieve certain required harmonic filtering targets. With these ideas in mind, the objective of this paper is to determine what size single tuned passive filters work in distribution networks best, in order to economically limit violations caused at a given point of common coupling (PCC). This article suggests that a single tuned passive filter could be employed in typical industrial power systems. Furthermore, constrained optimization can be used to find the optimal sizing of the passive filter in order to reduce both harmonic voltage and harmonic currents in the power system to an acceptable level, and, thus, improve the load power factor. The optimization technique works to minimize voltage total harmonic distortions (VTHD) and current total harmonic distortions (ITHD), where maintaining a given power factor at a specified range is desired. According to the IEEE Standard 519, both indices are viewed as constraints for the optimal passive filter design problem. The performance of this technique will be discussed using numerical examples taken from previous publications.

Keywords: harmonics, passive filter, power factor, power quality

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2296 Influence of Reinforcement Stiffness on the Performance of Back-to-Back Reinforced Earth Wall upon Rainwater Infiltration

Authors: Gopika Rajagopal, Sudheesh Thiyyakkandi

Abstract:

Back-to-back reinforced earth (RE) walls are extensively used in these days as bridge abutments and highway ramps, owing to their cost efficiency and ease of construction. High quality select fill is the most suitable backfill material due to its excellent engineering properties and constructability. However, industries are compelled to use low quality, locally available soil because of its ample availability on site. However, several failure cases of such walls are reported, especially subsequent to rainfall events. The stiffness of reinforcement is one of the major factors affecting the performance of RE walls. The present study focused on analyzing the effect of reinforcement stiffness on the performance of complete select fill, complete marginal fill, and hybrid-fill (i.e., combination of select and marginal fills) back-to-back RE walls, immediately after construction and upon rainwater infiltration through finite element modelling. A constant width to height (W/H) ratio of 3 and height (H) of 6 m was considered for the numerical analysis and the stiffness of reinforcement layers was varied from 500 kN/m to 10000 kN/m. Results showed that reinforcement stiffness had a noticeable influence on the response of RE wall, subsequent to construction as well as rainwater infiltration. Facing displacement was found to decrease and maximum reinforcement tension and factor of safety were observed to increase with increasing the stiffness of reinforcement. However, beyond a stiffness of 5000 kN/m, no significant reduction in facing displacement was observed. The behavior of fully marginal fill wall considered in this study was found to be reasonable even after rainwater infiltration when the high stiffness reinforcement layers are used.

Keywords: back-to-back reinforced earth wall, finite element modelling, rainwater infiltration, reinforcement stiffness

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2295 Computer-Aided Depression Screening: A Literature Review on Optimal Methodologies for Mental Health Screening

Authors: Michelle Nighswander

Abstract:

Suicide can be a tragic response to mental illness. It is difficult for people to disclose or discuss suicidal impulses. The stigma surrounding mental health can create a reluctance to seek help for mental illness. Patients may feel pressure to exhibit a socially desirable demeanor rather than reveal these issues, especially if they sense their healthcare provider is pressed for time or does not have an extensive history with their provider. Overcoming these barriers can be challenging. Although there are several validated depression and suicide risk instruments, varying processes used to administer these tools may impact the truthfulness of the responses. A literature review was conducted to find evidence of the impact of the environment on the accuracy of depression screening. Many investigations do not describe the environment and fewer studies use a comparison design. However, three studies demonstrated that computerized self-reporting might be more likely to elicit truthful and accurate responses due to increased privacy when responding compared to a face-to-face interview. These studies showed patients reported positive reactions to computerized screening for other stigmatizing health conditions such as alcohol use during pregnancy. Computerized self-screening for depression offers the possibility of more privacy and patient reflection, which could then send a targeted message of risk to the healthcare provider. This could potentially increase the accuracy while also increasing time efficiency for the clinic. Considering the persistent effects of mental health stigma, how these screening questions are posed can impact patients’ responses. This literature review analyzes trends in depression screening methodologies, the impact of setting on the results and how this may assist in overcoming one barrier caused by stigma.

Keywords: computerized self-report, depression, mental health stigma, suicide risk

Procedia PDF Downloads 126
2294 Effect of Oxytocin on Cytosolic Calcium Concentration of Alpha and Beta Cells in Pancreas

Authors: Rauza Sukma Rita, Katsuya Dezaki, Yuko Maejima, Toshihiko Yada

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Oxytocin is a nine-amino acid peptide synthesized in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) of the hypothalamus. Oxytocin promotes contraction of the uterus during birth and milk ejection during breast feeding. Although oxytocin receptors are found predominantly in the breasts and uterus of females, many tissues and organs express oxytocin receptors, including the pituitary, heart, kidney, thymus, vascular endothelium, adipocytes, osteoblasts, adrenal gland, pancreatic islets, and many cell lines. On the other hand, in pancreatic islets, oxytocin receptors are expressed in both α-cells and β-cells with stronger expression in α- cells. However, to our knowledge there are no reports yet about the effect of oxytocin on cytosolic calcium reaction on α and β-cell. This study aims to investigate the effect of oxytocin on α-cells and β-cells and its oscillation pattern. Islet of Langerhans from wild type mice were isolated by collagenase digestion. Isolated and dissociated single cells either α-cells or β-cells on coverslips were mounted in an open chamber and superfused in HKRB. Cytosolic concentration ([Ca2+]i) in single cells were measured by fura-2 microfluorimetry. After measurement of [Ca2+]i, α-cells were identified by subsequent immunocytochemical staining using an anti-glucagon antiserum. In β-cells, the [Ca2+]i increase in response to oxytocin was observed only under 8.3 mM glucose condition, whereas in α-cells, [Ca2+]i an increase induced by oxytocin was observed in both 2.8 mM and 8.3 mM glucose. The oscillation incidence was induced more frequently in β-cells compared to α-cells. In conclusion, the present study demonstrated that oxytocin directly interacts with both α-cells and β-cells and induces increase of [Ca2+]i and its specific patterns.

Keywords: α-cells, β-cells, cytosolic calcium concentration, oscillation, oxytocin

Procedia PDF Downloads 181