Search results for: constrained optimization problems
464 Health Counseling in the Republic of Estonia through Magazines (1930 – 1940): Striving for a European Lifestyle
Authors: Merle Talvik, Taimi Tulva, Kristi Puusepp, Ulle Ernits
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Background data. This is a study in the field of health humanities. The 1930s were years of rapid cultural and economic development in Europe and in Estonia. The urban way of life the glamorous lifestyle gained popularity, although the society of Estonia in the 1930s had traditionally been agrarian. People's free time increased, which needed to be filled with activities either at home or outside the home. Therefore, the number of popular magazines aimed at housewives increased. More than 200 magazines and bulletins were published in the Republic of Estonia before the Second World War (in 1934, the population of Estonia was 1,126,000). In the 1930s, the Republic of Estonia faced several challenges in healthcare. Infectious diseases, alcoholism, prostitution and child mortality had to be dealt with. Healers without medical education operated in the villages. For the average person, medical care was quite expensive, and despite efforts, by 1940, only 20% of the population was covered by health insurance. Advice published in popular family magazines provided help in solving, understanding and preventing health problems. Aim. The aim of the study is to analyze the health counseling through magazines during the Republic of Estonia (1930-1940) in historical and cultural context. Method. In total, 420 magazine issues were processed. An extensive textual analysis, as well as an analysis of photographs and illustrations from the aspect of health advice was carried out to achieve the research objective. Results. Health counseling was written by well-known doctors of the time, leaders of the abstinence movement and others. There was advice in various areas: prevention of infectious and non-infectious diseases and their treatment with simple methods, first aid, combating sexually transmitted diseases, women's and children's health, mental health, folk medicine techniques, abstinence, healthy eating, skin care, hygiene, introducing pharmacy products. Advice was offered in both written and visual form. Photos and illustrations helped to empower the health advice. Folk heritage and health knowledge of the time were relied upon, and a scientific point of view was popularized. Aspirations towards a European lifestyle were reflected in articles and illustrations. Contribution. The article has an ethnological attitude, and its impact comes down to understanding the history of health care in its socio-cultural context. The health counseling topics of the 1930s are also applicable in today's health education and research. Health counseling builds on the legacy of the past, and it helps to understand that the past is in the future and the main principles of health counseling arise from our history and background.Keywords: estonian republic, health counseling, lifestyle, magazines, media
Procedia PDF Downloads 64463 Organ Donation after Medical Aid in Dying: A Critical Study of Clinical Processes and Legal Rules in Place
Authors: Louise Bernier
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Under some jurisdictions (including Canada), eligible patients can request and receive medical assistance in dying (MAiD) through lethal injections, inducing their cardiocirculatory death. Those same patients can also wish to donate their organs in the process. If they qualify as organ donors, a clinical and ethical rule called the 'dead donor rule' (DDR) requires the transplant teams to wait after cardiocirculatory death is confirmed, followed by a 'no touch' period (5 minutes in Canada) before they can proceed with organ removal. The medical procedures (lethal injections) as well as the delays associated with the DDR can damage organs (mostly thoracic organs) due to prolonged anoxia. Yet, strong scientific evidences demonstrate that operating differently and reconsidering the DDR would result in more organs of better quality available for transplant. This idea generates discomfort and resistance, but it is also worth considering, especially in a context of chronic shortage of available organs. One option that could be examined for MAiD’ patients who wish and can be organ donors would be to remove vital organs while patients are still alive (and under sedation). This would imply accepting that patient’s death would occur through organ donation instead of lethal injections required under MAiD’ legal rules. It would also mean that patients requesting MAiD and wishing to be organ donors could aspire to donate better quality organs, including their heart, an altruistic gesture that carries important symbolic value for many donors and their families. Following a patient centered approach, our hypothesis is that preventing vital organ donation from a living donor in all circumstance is neither perfectly coherent with how legal mentalities have evolved lately in the field of fundamental rights nor compatible with the clinical and ethical frameworks that shape the landscape in which those complex medical decisions unfold. Through a study of the legal, ethical, and clinical rules in place, both at the national and international levels, this analysis raises questions on the numerous inconsistencies associated with respecting the DDR with patients who have chosen to die through MAiD. We will begin with an assessment of the erosion of certain national legal frameworks that pertain to the sacred nature of the right to life which now also includes the right to choose how one wishes to die. We will then study recent innovative clinical protocols tested in different countries to help address acute organ shortage problems in creative ways. We will conclude this analysis with an ethical assessment of the situation, referring to principles such as justice, autonomy, altruism, beneficence, and non-malfeasance. This study will build a strong argument in favor of starting to allow vital organ donations from living donors in countries where MAiD is already permitted.Keywords: altruism, autonomy, dead donor rule, medical assistance in dying, non-malfeasance, organ donation
Procedia PDF Downloads 178462 Household Socioeconomic Factors Associated with Teenage Pregnancies in Kigali City, Rwanda
Authors: Dieudonne Uwizeye, Reuben Muhayiteto
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Teenage pregnancy is a challenging problem for sustainable development due to restrictions it poses to socioeconomic opportunities for young mothers, their children and families. Being unable to take appropriate economic and social responsibilities, teen mothers get trapped into poverty and become economic burden to their family and country. Besides, teenage pregnancy is also a health problem because children born to very young mothers are vulnerable with greater risk of illnesses and deaths, and teenage mothers are more likely to be exposed to greater risk of maternal mortality and to other health and psychological problems. In Kigali city, in Rwanda, teenage pregnancy rate is currently high and its increase in recent years is worrisome. However, only individual factors influencing the teenage pregnancy tend to be the basis of interventions. It is important to understand the important socioeconomic factors at the household level that are associated with teenage pregnancy to help government, parents, and other stakeholders to appropriately address the problem with sustainable measures. This study analyzed secondary data from the Fifth Rwanda Demographic and Health Survey (RDHS-V 2014-2015) conducted by the National Institute of Statistics of Rwanda (NISR). The aim was to examine household socio-economic factors that are associated with incidence of teenage pregnancies in Kigali city. In addition to descriptive analysis, Pearson’s Chi Square and Binary Logistic Regression were used in the analysis. Findings indicate that marital status and age of household head, number of members in a household, number of rooms used for sleeping, educational level of the household head and household's wealth are significantly associated with teenage pregnancy in Rwanda ( p< 0.05). It was found that teenagers living with parents, those having parents with higher education and those from richer families are less likely to become pregnant. Age of household head was pinpointed as factor to teenage pregnancy, with teenage-headed households being more vulnerable. The findings also revealed that household composition correlates with the probability of teenage pregnancy (p < 0.05) with teenagers from households with less number of members being more vulnerable. Regarding the size of the house, the study suggested that the more rooms available in households, the less incidences of teenage pregnancy are likely to be observed (p < 0.05). However, teenage pregnancy was not significantly associated with physical violence among parents (p = 0.65) and sex of household heads (p = 0.52), except in teen-headed households of which female are predominantly heads. The study concludes that teenage pregnancy remains a serious social, economic and health problem in Rwanda. The study informs government officials, parents and other stakeholders to take interventions and preventive measures through community sex education, policies and strategies to foster effective parental guidance, care and control of young girls through meeting their necessary social and financial needs within households.Keywords: household socio-economic factors, Rwanda, Rwanda demographic and health survey, teenage pregnancy
Procedia PDF Downloads 179461 Effect of Two Types of Shoe Insole on the Dynamics of Lower Extremities Joints in Individuals with Leg Length Discrepancy during Stance Phase of Walking
Authors: Mansour Eslami, Fereshte Habibi
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Limb length discrepancy (LLD), or anisomeric, is defined as a condition in which paired limbs are noticeably unequal. Individuals with LLD during walking use compensatory mechanisms to dynamically lengthen the short limb and shorten the long limb to minimize the displacement of the body center of mass and consequently reduce body energy expenditure. Due to the compensatory movements created, LLD greater than 1 cm increases the odds of creating lumbar problems and hip and knee osteoarthritis. Insoles are non-surgical therapies that are recommended to improve the walking pattern, pain and create greater symmetry between the two lower limbs. However, it is not yet clear what effect insoles have on the variables related to injuries during walking. The aim of the present study was to evaluate the effect of internal and external heel lift insoles on pelvic kinematic in sagittal and frontal planes and lower extremity joint moments in individuals with mild leg length discrepancy during the stance phase of walking. Biomechanical data of twenty-eight men with structural leg length discrepancy of 10-25 mm were collected while they walked under three conditions: shoes without insole (SH), with internal heel lift insoles (IHLI) in shoes, and with external heal lift insole (EHLI). The tests were performed for both short and long legs. The pelvic kinematic and joint moment were measured with a motion capture system and force plate. Five walking trials were performed for each condition. The average value of five successful trials was used for further statistical analysis. Repeated measures ANCOVA with Bonferroni post hoc test were used for between-group comparisons (p ≤ 0.05). In both internal and external heel lift insoles (IHLI, EHLI), there was a significant decrease in the peak values of lateral and anterior pelvic tilts of the long leg, hip, and knee moments of a long leg and ankle moment of short leg (p ≤ 0.05). Furthermore, significant increases in peak values of lateral and anterior pelvic tilt of short leg in IHLI and EHLI were observed as compared to Shoe (SH) condition (p ≤ 0.01). In addition, a significant difference was observed between the IHLI and EHLI conditions in peak anterior pelvic tilt of long leg and plantar flexor moment of short leg (p=0.04; p= 0.04 respectively). Our findings indicate that both IHLI and EHLI can play an important role in controlling excessive pelvic movements in the sagittal and frontal planes in individuals with mild LLD during walking. Furthermore, the EHLI may have a better effect in preventing musculoskeletal injuries compared to the IHLI.Keywords: kinematic, leg length discrepancy, shoe insole, walking
Procedia PDF Downloads 119460 Employment of Persons with Disabilities in Georgia: Challenges and Perspectives
Authors: Tamar Makharadze, Anastasia Kitiashvili, Irine Zhvania, Tamar Abashidze
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After ratification of UN Convention on the Rights of Persons with Disabilities (UN CRPD) by the Parliament of Georgia in 2013, ensuring equal access to education and employment for people with disabilities has become one of the priorities of the government. The current research has analyzed the attitudes of people with disabilities, employers and society towards various challenges that employment of persons with disabilities faces in Georgia. The study has been carried out in the capital city and three towns in West and East Georgia. Both quantitative and qualitative research methods have been used. Employers’ attitudes have been studied by analyzing research data from six focus groups and 12 in-depth interviews. Views of persons with disabilities have been analyzed relied on data from eight focus groups and 14 in-depth interviews. The quantitative study covered 490 surveyed respondents from four cities in Georgia. The research was carried out with the employees of companies selected based on the Simple Random Sample; in each company, based on the size of the company 7–10 employees were surveyed. A survey was conducted using a specially developed structured questionnaire. Data analysis was carried out using SPSS (21.0). The research was carried out during June-August 2015. The research data shows that both qualitative and quantitative research participants view employment of persons with disabilities positively; however persons with severe intellectual disabilities and mental problems are viewed as less workable and desired at workplaces. The respondents support the idea of employment of persons with disabilities at an open labour market; at the same time idea of a development of sheltered workshops is also supported. The vast majority of research participants believe that employers should be rather encouraged to hire persons with disabilities than force them to do so. For employers it is important to have the state assistance in adjusting working place to the needs of employee with disabilities. Some tax benefits for employers having employees with disabilities also are seen as encouraging employment of persons with disabilities. Both employers and persons with disabilities believe that development of job coaching will help persons with disabilities to find and maintain a job at the open market. Majority of survey respondents think that the main reasons discouraging employment of persons with disabilities in Georgia are: poor socioeconomic background and high level of unemployment in the country, absence of related state programs and existed stigma towards persons with disabilities within the society. To conclude it can be said that both employers and persons with disabilities expect initiative from the government – development of the programs and services focusing on employment of persons with disabilities that will be rather encouraging and supporting than punishing and forcing. Relied on survey data it can be said that people have positive attitudes to see persons with disabilities at workplaces, educational institutions and public places. This creates a good background for extensive and consistent work towards social inclusion of persons with disabilities in Georgia.Keywords: supported employment, job coaching, employment of persons with disabilities in Georgia, social inclusion
Procedia PDF Downloads 354459 Solution-Focused Wellness: An Evidence-Based Approach to Wellness Promotion
Authors: James Beauchemin
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Research indicates that college students are experiencing mental health challenges of greater severity, and an increased number of students are seeking help. Contributing to the compromised wellness of the college student population are the prevalence of unhealthy lifestyle habits and behaviors such as alcohol consumption, tobacco use, dietary concerns, risky sexual behaviors, and lack of physical activity. Alternative approaches are needed for this population that emphasize prevention and holistic lifestyle change that mitigate mental health and wellness challenges and alleviate strain on campus resources. This presentation will introduce a Solution-Focused Wellness (SFW) intervention model and examine wellness domains solution-focused strategies to promote personal well-being, and provide supporting research from multiple studies that illustrate intervention effectiveness with a collegiate population. Given the subjective and personal nature of wellness, a therapeutic approach that provides the opportunity for individuals to conceptualize and operationalize wellness themselves is critical to facilitating lasting wellness-based change. Solution-Focused Brief Therapy (SFBT) is a strength-based modality defined by its emphasis on constructing solutions rather than focusing on problems and the assumption that clients have the resources and capacity to change. SFBT has demonstrated effectiveness as a brief therapeutic intervention with the college population in groups and related to health and wellness. By integrating SFBT strategies with personal wellness, a brief intervention was developed to support college students in establishing lifestyles trends consistent with their conceptualizations of wellness. Research supports the effectiveness of a SFW model in improving college student wellness in both face-to-face and web-based formats. Outcomes of controlled and longitudinal studies will be presented, demonstrating significant improvements in perceptions of stress, life satisfaction, happiness, mental health, well-being, and resilience. Overall, there is compelling evidence that utilization of a Solution-Focused Brief Therapy approach with college students can help to improve personal wellness and establish healthy lifestyle trends, providing an effective prevention-focused strategy for college counseling centers and wellness centers to employ. Primary research objectives include: 1)establish an evidence-based approach to facilitating wellness pro motion among the college student population, 2) examine the effectiveness of a Solution-Focused Wellness (SFW) intervention model in decreasing stress, improving personal wellness, mental health, life satisfaction, and resiliency,3) investigate intervention impacts over time (e.g. 6-week post-intervention), and 4) demonstrate SFW intervention utility in wellness promotion and associated outcomes when compared with no-treatment control, and alternative intervention approaches.Keywords: wellness, college students, solution-focused, prevention
Procedia PDF Downloads 72458 The Role of Interest Groups in Foreign Policy: Assessing the Influence of the 'Pro-Jakarta Lobby' in Australia and Indonesia's Bilateral Relations
Authors: Bec Strating
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This paper examines the ways that domestic politics and pressure–generated through lobbying, public diplomacy campaigns and other tools of soft power-contributes to the formation of short-term and long-term national interests, priorities and strategies of states in their international relations. It primarily addresses the conceptual problems regarding the kinds of influence that lobby groups wield in foreign policy and how this influence might be assessed. Scholarly attention has been paid to influential foreign policy lobbies and interest groups, particularly in the areas of US foreign policy. Less attention has been paid to how lobby groups might influence the foreign policy of a middle power such as Australia. This paper examines some of the methodological complexities in developing and conducting a research project that can measure the nature and influence of lobbies on foreign affairs priorities and activities. This paper will use Australian foreign policy in the context of its historical bilateral relationship with Indonesia as a case study for considering the broader issues of domestic influences on foreign policy. Specifically, this paper will use the so-called ‘pro-Jakarta lobby’ as an example of an interest group. The term ‘pro-Jakarta lobby’ is used in media commentary and scholarship to describe an amorphous collection of individuals who have sought to influence Australian foreign policy in favour of Indonesia. The term was originally applied to a group of Indonesian experts at the Australian National University in the 1980s but expanded to include journalists, think tanks and key diplomats. The concept of the ‘pro-Jakarta lobby’ was developed largely through criticisms of Australia’s support for Indonesia’s sovereignty of East Timor and West Papua. Pro-Independence supporters were integral for creating the ‘lobby’ in their rhetoric and criticisms about the influence on Australian foreign policy. In these critical narratives, the ‘pro-Jakarta lobby’ supported a realist approach to relations with Indonesia during the years of President Suharto’s regime, which saw appeasement of Indonesia as paramount to values of democracy and human rights. The lobby was viewed as integral in embedding a form of ‘foreign policy exceptionalism’ towards Indonesia in Australian policy-making circles. However, little critical and scholarly attention has been paid to nature, aims, strategies and activities of the ‘pro-Jakarta lobby.' This paper engages with methodological issues of foreign policy analysis: what was the ‘pro-Jakarta lobby’? Why was it considered more successful than other activist groups in shaping policy? And how can its influence on Australia’s approach to Indonesia be tested in relation to other contingent factors shaping policy? In addressing these questions, this case study will assist in addressing a broader scholarly concern about the capacities of collectives or individuals in shaping and directing the foreign policies of states.Keywords: foreign policy, interests groups, Australia, Indonesia
Procedia PDF Downloads 343457 Impact of Collieries on Groundwater in Damodar River Basin
Authors: Rajkumar Ghosh
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The industrialization of coal mining and related activities has a significant impact on groundwater in the surrounding areas of the Damodar River. The Damodar River basin, located in eastern India, is known as the "Ruhr of India" due to its abundant coal reserves and extensive coal mining and industrial operations. One of the major consequences of collieries on groundwater is the contamination of water sources. Coal mining activities often involve the excavation and extraction of coal through underground or open-pit mining methods. These processes can release various pollutants and chemicals into the groundwater, including heavy metals, acid mine drainage, and other toxic substances. As a result, the quality of groundwater in the Damodar River region has deteriorated, making it unsuitable for drinking, irrigation, and other purposes. The high concentration of heavy metals, such as arsenic, lead, and mercury, in the groundwater has posed severe health risks to the local population. Prolonged exposure to contaminated water can lead to various health problems, including skin diseases, respiratory issues, and even long-term ailments like cancer. The contamination has also affected the aquatic ecosystem, harming fish populations and other organisms dependent on the river's water. Moreover, the excessive extraction of groundwater for industrial processes, including coal washing and cooling systems, has resulted in a decline in the water table and depletion of aquifers. This has led to water scarcity and reduced availability of water for agricultural activities, impacting the livelihoods of farmers in the region. Efforts have been made to mitigate these issues through the implementation of regulations and improved industrial practices. However, the historical legacy of coal industrialization continues to impact the groundwater in the Damodar River area. Remediation measures, such as the installation of water treatment plants and the promotion of sustainable mining practices, are essential to restore the quality of groundwater and ensure the well-being of the affected communities. In conclusion, the coal industrialization in the Damodar River surrounding has had a detrimental impact on groundwater. This research focuses on soil subsidence induced by the over-exploitation of ground water for dewatering open pit coal mines. Soil degradation happens in arid and semi-arid regions as a result of land subsidence in coal mining region, which reduces soil fertility. Depletion of aquifers, contamination, and water scarcity are some of the key challenges resulting from these activities. It is crucial to prioritize sustainable mining practices, environmental conservation, and the provision of clean drinking water to mitigate the long-lasting effects of collieries on the groundwater resources in the region.Keywords: coal mining, groundwater, soil subsidence, water table, damodar river
Procedia PDF Downloads 80456 Assessment of the Growth Enhancement Support Scheme in Adamawa State, Nigeria
Authors: Oto J. Okwu, Ornan Henry, Victor A. Otene
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The agricultural sector contributes a great deal to the sustenance of Nigeria’s food security and economy, with an attendant impact on rural development. In spite of the relatively high number of farmers in the country, self-sufficiency in food production is still a challenge. Farmers are faced with myriad problems which hinder their production efficiency, one of which is their access to agricultural inputs required for optimum production. To meet the challenges faced by farmers, the government at the federal level has come up with many agricultural policies, one of which is the Agricultural Transformation Agenda (ATA). The Growth Enhancement Support Scheme (GESS) is one of the critical components of ATA, which is aimed at ensuring the effective distribution of agricultural inputs delivered directly to farmers, and at a regulated cost. After about 8 years of launching this policy, it will be necessary to carry out an assessment of GESS and determine the impact it has made on rural farmers with respect to their access to farm inputs. This study was carried out to assess the Growth Enhancement Support Scheme (GESS) in Adamawa State, Nigeria. Crop farmers who registered under the GESS in Adamawa State, Nigeria, formed the population for the study. Primary data for the study were obtained through a survey, and the use of a structured questionnaire. A sample size of 167 respondents was selected using multi-stage, purposive, and random sampling techniques. The validity and reliability of the research instrument (questionnaire) were obtained through pilot testing and test-retest method, respectively. The objectives of the study were to determine the difference in the level of access to agricultural inputs before and after GESS, determine the difference in cost of agricultural inputs before and after GESS, and to determine the challenges faced by rural farmers in accessing agricultural inputs through GESS. Both descriptive and inferential statistics were used in analyzing the collected data. Specifically, Mann-Whitney, student t-test, and factor analysis were used to test the stated hypotheses. Research findings revealed there was a significant difference in the level of access to farm inputs after the introduction of GESS (Z=14.216). Also, there was a significant difference in the cost of agro-inputs after the introduction of GESS (Pr |T| > |t|= 0.0000). The challenges faced by respondents in accessing agro-inputs through GESS were administrative and technical in nature. Based on the findings of the research, it was recommended that efforts be made by the government to sustain the GESS, as it has significantly improved the level of farmers’ access to agricultural inputs and has reduced the cost of agro-inputs, while administrative challenges faced by the respondents in accessing inputs be addressed by the government, and extension agents assist the farmers to overcome the technical challenges they face in accessing inputs.Keywords: agricultural policy, agro-inputs, assessment, growth enhancement support scheme, rural farmers
Procedia PDF Downloads 109455 Metaphors, Cognition, and Action: Conceptual Metaphor Analysis of President Akuffo-Addo’s Speeches in the COVID-19 Crisis
Authors: Isaac Kwabena Adubofour, Esther Serwaah Afreh
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Political speeches are structured in ways that ensure that the ideology of the leader is communicated in ways that the opinions of the audience are influenced towards certain lines of action, and in crisis situations like the outbreak of a global pandemic, public opinion and action are influenced through speeches. The foregoing explains the presence of metaphors in presidential speeches. Crises require, among other things, that the thoughts, emotions, and actions of the population are controlled in dealing with the problems at hand. The primary question this study assesses is how the use of metaphors in crisis situations, like the COVID-19 pandemic, influences thought, determines the policies a government adopts, and influences the reactions of the people. The study focused on twenty-four (24) addresses of the President of Ghana, Nana Addo Danquah Akuffo-Addo, on the COVID-19 pandemic and his government’s efforts to manage the crisis. The nature and relevance of presidential speeches and the presence of metaphors in such speeches have been investigated. However, there is a paucity of research on the connection between the presence of metaphors in presidential speeches and their influence on thought and action. Especially within the crisis of the COVID-19 pandemic, it is pertinent to investigate how the presence of metaphors in presidential addresses influences social thought and action. Thus, the current study sought to investigate the potential for metaphor use to influence thought and action on a national scale during the COVID crisis. The speeches were collected from the website of the presidency. The analysis was done using Metaphor Identification Process by the Praglejazz Group (2007) with conceptual metaphor theory (Lakoff & Johnson, 1980) as the theoretical foundation. The findings of the study show that the President’s adoption of war metaphors may not have been ideal since it triggered thoughts, policies, and social actions in line with war. For instance, the reference to health workers as heroes, heroines, and frontline workers praised the efforts of these workers over the efforts of the rest of the population, and that may have contributed to the apathy that arose among the citizens in dealing with the pandemic. This prioritization of the frontline workers explains why their taxes were forgiven for a considerable period. The government further absorbed utility bills of citizens during the pandemic. All these financial commitments may not have been advisable for a developing country like Ghana, but the authors argue that the actions may have been influenced by the metaphor that was adopted. Another finding that is explored is the problem of stigmatization in the country during the pandemic and its connection with the war metaphor. This investigation expands the research on metaphors, social thought and action, and crisis communication. Its contribution to metaphor use, thought, and action suggest its potential implication for education and other fields.Keywords: conceptual metaphor theory, COVID-19, crisis communication, presidential addresses, risk communication
Procedia PDF Downloads 104454 Discovering the Effects of Meteorological Variables on the Air Quality of Bogota, Colombia, by Data Mining Techniques
Authors: Fabiana Franceschi, Martha Cobo, Manuel Figueredo
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Bogotá, the capital of Colombia, is its largest city and one of the most polluted in Latin America due to the fast economic growth over the last ten years. Bogotá has been affected by high pollution events which led to the high concentration of PM10 and NO2, exceeding the local 24-hour legal limits (100 and 150 g/m3 each). The most important pollutants in the city are PM10 and PM2.5 (which are associated with respiratory and cardiovascular problems) and it is known that their concentrations in the atmosphere depend on the local meteorological factors. Therefore, it is necessary to establish a relationship between the meteorological variables and the concentrations of the atmospheric pollutants such as PM10, PM2.5, CO, SO2, NO2 and O3. This study aims to determine the interrelations between meteorological variables and air pollutants in Bogotá, using data mining techniques. Data from 13 monitoring stations were collected from the Bogotá Air Quality Monitoring Network within the period 2010-2015. The Principal Component Analysis (PCA) algorithm was applied to obtain primary relations between all the parameters, and afterwards, the K-means clustering technique was implemented to corroborate those relations found previously and to find patterns in the data. PCA was also used on a per shift basis (morning, afternoon, night and early morning) to validate possible variation of the previous trends and a per year basis to verify that the identified trends have remained throughout the study time. Results demonstrated that wind speed, wind direction, temperature, and NO2 are the most influencing factors on PM10 concentrations. Furthermore, it was confirmed that high humidity episodes increased PM2,5 levels. It was also found that there are direct proportional relationships between O3 levels and wind speed and radiation, while there is an inverse relationship between O3 levels and humidity. Concentrations of SO2 increases with the presence of PM10 and decreases with the wind speed and wind direction. They proved as well that there is a decreasing trend of pollutant concentrations over the last five years. Also, in rainy periods (March-June and September-December) some trends regarding precipitations were stronger. Results obtained with K-means demonstrated that it was possible to find patterns on the data, and they also showed similar conditions and data distribution among Carvajal, Tunal and Puente Aranda stations, and also between Parque Simon Bolivar and las Ferias. It was verified that the aforementioned trends prevailed during the study period by applying the same technique per year. It was concluded that PCA algorithm is useful to establish preliminary relationships among variables, and K-means clustering to find patterns in the data and understanding its distribution. The discovery of patterns in the data allows using these clusters as an input to an Artificial Neural Network prediction model.Keywords: air pollution, air quality modelling, data mining, particulate matter
Procedia PDF Downloads 258453 Carbon Dioxide Capture and Utilization by Using Seawater-Based Industrial Wastewater and Alkanolamine Absorbents
Authors: Dongwoo Kang, Yunsung Yoo, Injun Kim, Jongin Lee, Jinwon Park
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Since industrial revolution, energy usage by human-beings has been drastically increased resulting in the enormous emissions of carbon dioxide into the atmosphere. High concentration of carbon dioxide is well recognized as the main reason for the climate change by breaking the heat equilibrium of the earth. In order to decrease the amount of carbon dioxide emission, lots of technologies have been developed. One of the methods is to capture carbon dioxide after combustion process using liquid type absorbents. However, for some nations, captured carbon dioxide cannot be treated and stored properly due to their geological structures. Also, captured carbon dioxide can be leaked out when crust activities are active. Hence, the method to convert carbon dioxide as stable and useful products were developed. It is usually called CCU, that is, Carbon Capture and Utilization. There are several ways to convert carbon dioxide into useful substances. For example, carbon dioxide can be converted and used as fuels such as diesel, plastics, and polymers. However, these types of technologies require lots of energy to make stable carbon dioxide into a reactive one. Hence, converting it into metal carbonates salts have been studied widely. When carbon dioxide is captured by alkanolamine-based liquid absorbents, it exists as ionic forms such as carbonate, carbamate, and bicarbonate. When adequate metal ions are added, metal carbonate salt can be produced by ionic reaction with fast reaction kinetics. However, finding metal sources can be one of the problems for this method to be commercialized. If natural resources such as calcium oxide were used to supply calcium ions, it is not thought to have the economic feasibility to use natural resources to treat carbon dioxide. In this research, high concentrated industrial wastewater produced from refined salt production facility have been used as metal supplying source, especially for calcium cations. To ensure purity of final products, calcium ions were selectively separated in the form of gypsum dihydrate. After that, carbon dioxide is captured using alkanolamine-based absorbents making carbon dioxide into reactive ionic form. And then, high purity calcium carbonate salt was produced. The existence of calcium carbonate was confirmed by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) images. Also, carbon dioxide loading curves for absorption, conversion, and desorption were provided. Also, in order to investigate the possibility of the absorbent reuse, reabsorption experiments were performed either. Produced calcium carbonate as final products is seemed to have potential to be used in various industrial fields including cement and paper making industries and pharmaceutical engineering fields.Keywords: alkanolamine, calcium carbonate, climate change, seawater, industrial wastewater
Procedia PDF Downloads 185452 Research on the Updating Strategy of Public Space in Small Towns in Zhejiang Province under the Background of New-Style Urbanization
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Small towns are the most basic administrative institutions in our country, which are connected with cities and rural areas. Small towns play an important role in promoting local urban and rural economic development, providing the main public services and maintaining social stability in social governance. With the vigorous development of small towns and the transformation of industrial structure, the changes of social structure, spatial structure, and lifestyle are lagging behind, causing that the spatial form and landscape style do not belong to both cities and rural areas, and seriously affecting the quality of people’s life space and environment. The rural economy in Zhejiang Province has started, the society and the population are also developing in relative stability. In September 2016, Zhejiang Province set out the 'Technical Guidelines for Comprehensive Environmental Remediation of Small Towns in Zhejiang Province,' so as to comprehensively implement the small town comprehensive environmental remediation with the main content of strengthening the plan and design leading, regulating environmental sanitation, urban order and town appearance. In November 2016, Huzhou City started the comprehensive environmental improvement of small towns, strived to use three years to significantly improve the 115 small towns, as well as to create a number of high quality, distinctive and beautiful towns with features of 'clean and livable, rational layout, industrial development, poetry and painting style'. This paper takes Meixi Town, Zhangwu Town and Sanchuan Village in Huzhou City as the empirical cases, analyzes the small town public space by applying the relative theory of actor-network and space syntax. This paper also analyzes the spatial composition in actor and social structure elements, as well as explores the relationship of actor’s spatial practice and public open space by combining with actor-network theory. This paper introduces the relevant theories and methods of spatial syntax, carries out research analysis and design planning analysis of small town spaces from the perspective of quantitative analysis. And then, this paper proposes the effective updating strategy for the existing problems in public space. Through the planning and design in the building level, the dissonant factors produced by various spatial combination of factors and between landscape design and urban texture during small town development will be solved, inhabitant quality of life will be promoted, and town development vitality will be increased.Keywords: small towns, urbanization, public space, updating
Procedia PDF Downloads 228451 Research Insights into Making the Premises Spiritually Pure
Authors: Jayant Athavale, Rendy Ekarantio, Sean Clarke
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The Maharshi University of Spirituality was founded on the base of 30 years of spiritual research. It specializes in conducting research on how the subtle-world and spiritual-vibrations affect the lives of people. One such area of research is how to create spiritually positive vibrations in the premises. By using aura and energy scanners along with the sixth sense, the spiritual research team has identified 3 aspects that are instrumental in enhancing or reducing the spiritual positivity of any premises. Firstly, the characteristics of the land should be considered holistically, that is, from a physical, psychological and spiritual point of view. While procedures for the physical assessment of land are well documented, due to ignorance and disbelief, the spiritual aspects are not considered. For example, if the land was previously a graveyard site, it can have highly detrimental effects on the residents within the premises at the spiritual level. This can further manifest as physical and psychological problems that are faced by the residents. Secondly, the manner of construction and the purpose/use of the building affects the subtle-vibrations in the premises. The manner of construction includes gross aspects such as the materials used, kind of architecture, etc. It also includes the subtle aspects provided in detail in the ancient science of Vastu Shastra and Feng Shui. For example, having the front door of the premises facing the south direction can negatively affect the premises because the southern direction is prone to distressing vibrations. The purpose and use of the premises also plays an important role in determining the type of subtle-vibrations that will be predominantly found within its area. Thirdly, the actions, thoughts, value systems and attitudes of the residents play an important part in determining whether the subtle-vibrations will be positive or negative. Residents with many personality defects emit negative vibrations. If some of the residents are affected with negative energies and are not doing any spiritual practice to overcome it, then it can have a harmful spiritual effect on the rest of the residents and the premises. If these three aspects are appropriately considered and attended to, then the premises will generate higher levels of spiritually positive vibrations. Both living and non-living objects within the premises imbibe this positivity and therefore, it holistically enhances the overall well-being of its residents. The positivity experienced in the premises of the Spiritual Research Centre of the Maharshi University of Spirituality, is a testimony to the success of this research. Due to regular and intense spiritual practice carried out by 10 Saints and over 500 seekers residing in its premises, the positivity in the environment can be felt by people when they enter its premises and even from a distance, and can easily be picked up by aura and energy scanners. Extraordinary and fascinating phenomena are observed and experienced in its premises as both living and non-living objects emit spiritually positive vibrations. This also protects the residents from negative vibrations. Examples of such phenomena and their positive impact are discussed in the paper.Keywords: negative energies, positive vibrations on the premises, resident’s spiritual practice, science of the premises
Procedia PDF Downloads 149450 Efficiency of Different Types of Addition onto the Hydration Kinetics of Portland Cement
Authors: Marine Regnier, Pascal Bost, Matthieu Horgnies
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Some of the problems to be solved for the concrete industry are linked to the use of low-reactivity cement, the hardening of concrete under cold-weather and the manufacture of pre-casted concrete without costly heating step. The development of these applications needs to accelerate the hydration kinetics, in order to decrease the setting time and to obtain significant compressive strengths as soon as possible. The mechanisms enhancing the hydration kinetics of alite or Portland cement (e.g. the creation of nucleation sites) were already studied in literature (e.g. by using distinct additions such as titanium dioxide nanoparticles, calcium carbonate fillers, water-soluble polymers, C-S-H, etc.). However, the goal of this study was to establish a clear ranking of the efficiency of several types of additions by using a robust and reproducible methodology based on isothermal calorimetry (performed at 20°C). The cement was a CEM I 52.5N PM-ES (Blaine fineness of 455 m²/kg). To ensure the reproducibility of the experiments and avoid any decrease of the reactivity before use, the cement was stored in waterproof and sealed bags to avoid any contact with moisture and carbon dioxide. The experiments were performed on Portland cement pastes by using a water-to-cement ratio of 0.45, and incorporating different compounds (industrially available or laboratory-synthesized) that were selected according to their main composition and their specific surface area (SSA, calculated using the Brunauer-Emmett-Teller (BET) model and nitrogen adsorption isotherms performed at 77K). The intrinsic effects of (i) dry powders (e.g. fumed silica, activated charcoal, nano-precipitates of calcium carbonate, afwillite germs, nanoparticles of iron and iron oxides , etc.), and (ii) aqueous solutions (e.g. containing calcium chloride, hydrated Portland cement or Master X-SEED 100, etc.) were investigated. The influence of the amount of addition, calculated relatively to the dry extract of each addition compared to cement (and by conserving the same water-to-cement ratio) was also studied. The results demonstrated that the X-SEED®, the hydrated calcium nitrate, the calcium chloride (and, at a minor level, a solution of hydrated Portland cement) were able to accelerate the hydration kinetics of Portland cement, even at low concentration (e.g. 1%wt. of dry extract compared to cement). By using higher rates of additions, the fumed silica, the precipitated calcium carbonate and the titanium dioxide can also accelerate the hydration. In the case of the nano-precipitates of calcium carbonate, a correlation was established between the SSA and the accelerating effect. On the contrary, the nanoparticles of iron or iron oxides, the activated charcoal and the dried crystallised hydrates did not show any accelerating effect. Future experiments will be scheduled to establish the ranking of these additions, in terms of accelerating effect, by using low-reactivity cements and other water to cement ratios.Keywords: acceleration, hydration kinetics, isothermal calorimetry, Portland cement
Procedia PDF Downloads 256449 Analysis Rescuers' Viewpoint about Victims Tracking in Earthquake by Using Radio Frequency Identification (RFID)
Authors: Sima Ajami, Batool Akbari
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Background: Radio frequency identification (RFID) system has been successfully applied to the areas of manufacturing, supply chain, agriculture, transportation, healthcare, and services. The RFID is already used to track and trace the victims in a disaster situation. Data can be collected in real time and be immediately available to emergency personnel and saves time by the RFID. Objectives: The aim of this study was, first, to identify stakeholders and customers for rescuing earthquake victims, second, to list key internal and external factors to use RFID to track earthquake victims, finally, to assess SWOT for rescuers' viewpoint. Materials and Methods: This study was an applied and analytical study. The study population included scholars, experts, planners, policy makers and rescuers in the "red crescent society of Isfahan province", "disaster management Isfahan province", "maintenance and operation department of Isfahan", "fire and safety services organization of Isfahan municipality", and "medical emergencies and disaster management center of Isfahan". After that, researchers held a workshop to teach participants about RFID and its usages in tracking earthquake victims. In the meanwhile of the workshop, participants identified, listed, and weighed key internal factors (strengths and weaknesses; SW) and external factors (opportunities and threats; OT) to use RFID in tracking earthquake victims. Therefore, participants put weigh strengths, weaknesses, opportunities, and threats (SWOT) and their weighted scales were calculated. Then, participants' opinions about this issue were assessed. Finally, according to the SWOT matrix, strategies to solve the weaknesses, problems, challenges, and threats through opportunities and strengths were proposed by participants. Results: The SWOT analysis showed that the total weighted score for internal and external factors were 3.91 (Internal Factor Evaluation) and 3.31 (External Factor Evaluation) respectively. Therefore, it was in a quadrant SO strategies cell in the SWOT analysis matrix and aggressive strategies were resulted. Organizations, scholars, experts, planners, policy makers and rescue workers should plan to use RFID technology in order to save more victims and manage their life. Conclusions: Researchers suppose to apply SO strategies and use a firm’s internal strength to take advantage of external opportunities. It is suggested, policy maker should plan to use the most developed technologies to save earthquake victims and deliver the easiest service to them. To do this, education, informing, and encouraging rescuers to use these technologies is essential. Originality/ Value: This study was a research paper that showed how RFID can be useful to track victims in earthquake.Keywords: frequency identification system, strength, weakness, earthquake, victim
Procedia PDF Downloads 322448 Rainfall and Flood Forecast Models for Better Flood Relief Plan of the Mae Sot Municipality
Authors: S. Chuenchooklin, S. Taweepong, U. Pangnakorn
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This research was conducted in the Mae Sot Watershed whereas located in the Moei River Basin at the Upper Salween River Basin in Tak Province, Thailand. The Mae Sot Municipality is the largest urbanized in Tak Province and situated in the midstream of the Mae Sot Watershed. It usually faces flash flood problem after heavy rain due to poor flood management has been reported since economic rapidly bloom up in recently years. Its catchment can be classified as ungauged basin with lack of rainfall data and no any stream gaging station was reported. It was attached by most severely flood event in 2013 as the worst studied case for those all communities in this municipality. Moreover, other problems are also faced in this watershed such shortage water supply for domestic consumption and agriculture utilizations including deterioration of water quality and landslide as well. The research aimed to increase capability building and strengthening the participation of those local community leaders and related agencies to conduct better water management in urban area was started by mean of the data collection and illustration of appropriated application of some short period rainfall forecasting model as the aim for better flood relief plan and management through the hydrologic model system and river analysis system programs. The authors intended to apply the global rainfall data via the integrated data viewer (IDV) program from the Unidata with the aim for rainfall forecasting in short period of 7 - 10 days in advance during rainy season instead of real time record. The IDV product can be present in advance period of rainfall with time step of 3 - 6 hours was introduced to the communities. The result can be used to input to either the hydrologic modeling system model (HEC-HMS) or the soil water assessment tool model (SWAT) for synthesizing flood hydrographs and use for flood forecasting as well. The authors applied the river analysis system model (HEC-RAS) to present flood flow behaviors in the reach of the Mae Sot stream via the downtown of the Mae Sot City as flood extents as water surface level at every cross-sectional profiles of the stream. Both models of HMS and RAS were tested in 2013 with observed rainfall and inflow-outflow data from the Mae Sot Dam. The result of HMS showed fit to the observed data at dam and applied at upstream boundary discharge to RAS in order to simulate flood extents and tested in the field, and the result found satisfied. The result of IDV’s rainfall forecast data was compared to observed data and found fair. However, it is an appropriate tool to use in the ungauged catchment to use with flood hydrograph and river analysis models for future efficient flood relief plan and management.Keywords: global rainfall, flood forecast, hydrologic modeling system, river analysis system
Procedia PDF Downloads 349447 Modeling of Alpha-Particles’ Epigenetic Effects in Short-Term Test on Drosophila melanogaster
Authors: Z. M. Biyasheva, M. Zh. Tleubergenova, Y. A. Zaripova, A. L. Shakirov, V. V. Dyachkov
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In recent years, interest in ecogenetic and biomedical problems related to the effects on the population of radon and its daughter decay products has increased significantly. Of particular interest is the assessment of the consequence of irradiation at hazardous radon areas, which includes the Almaty region due to the large number of tectonic faults that enhance radon emanation. In connection with the foregoing, the purpose of this work was to study the genetic effects of exposure to supernormal radon doses on the alpha-radiation model. Irradiation does not affect the growth of the cell, but rather its ability to differentiate. In addition, irradiation can lead to somatic mutations, morphoses and modifications. These damages most likely occur from changes in the composition of the substances of the cell. Such changes are epigenetic since they affect the regulatory processes of ontogenesis. Variability in the expression of regulatory genes refers to conditional mutations that modify the formation of signs of intraspecific similarity. Characteristic features of these conditional mutations are the dominant type of their manifestation, phenotypic asymmetry and their instability in the generations. Currently, the terms “morphosis” and “modification” are used to describe epigenetic variability, which are maintained in Drosophila melanogaster cultures using linkaged X- chromosomes, and the mutant X-chromosome is transmitted along the paternal line. In this paper, we investigated the epigenetic effects of alpha particles, whose source in nature is mainly radon and its daughter decay products. In the experiment, an isotope of plutonium-238 (Pu238), generating radiation with an energy of about 5500 eV, was used as a source of alpha particles. In an experiment in the first generation (F1), deformities or morphoses were found, which can be called "radiation syndromes" or mutations, the manifestation of which is similar to the pleiotropic action of genes. The proportion of morphoses in the experiment was 1.8%, and in control 0.4%. In this experiment, the morphoses in the flies of the first and second generation looked like black spots, or melanomas on different parts of the imago body; "generalized" melanomas; curled, curved wings; shortened wing; bubble on one wing; absence of one wing, deformation of thorax, interruption and violation of tergite patterns, disruption of distribution of ocular facets and bristles; absence of pigmentation of the second and third legs. Statistical analysis by the Chi-square method showed the reliability of the difference in experiment and control at P ≤ 0.01. On the basis of this, it can be considered that alpha particles, which in the environment are mainly generated by radon and its isotopes, have a mutagenic effect that manifests itself, mainly in the formation of morphoses or deformities.Keywords: alpha-radiation, genotoxicity, morphoses, radioecology, radon
Procedia PDF Downloads 152446 Phenolic Composition and Contribution of Individual Compounds to Antioxidant Activity of Malus domestica Borkh Fruit Cultivars
Authors: Raudone Lina, Raudonis Raimondas, Liaudanskas Mindaugas, Pukalskas Audrius, Viskelis Pranas, Janulis Valdimaras
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Human health fortification, its protection and disease prophylaxis are the main problems of the health care systems. Plant origin materials and their preparations are applied for the prevention of the common diseases. Oxidative stress takes part in the pathogenesis of many autoimmune, neurodegenerative, tumor and ageing processes. The antioxidants are able to protect the human body from the free radicals and to stop the progression of numerous chronic diseases. The research of plant origin materials is relevant for the search of natural antioxidants. A group of compounds that gained scientific attention due to antioxidant properties and effects on human health are phenolic compounds. Phenolic compounds are widely abundant in various parts of plants, i.e. leaves, stems, roots, flowers and fruits. Most commonly consumed fruits all over the world are apples. It is very important to analyze the antioxidant activity of apples as they are extensively used in the prevention of various diseases. The aim of this study was to determine the antioxidant profiles of Malus domestica Borkh fruit cultivars (Aldas, Auksis, Connel Red, Ligol, Lodel, Rajka) and to identify the phenolic compounds with potent contribution to antioxidant activity. Nineteen constituents were identified in apple cultivars using ultra high performance liquid chromatography coupled to quadruple and time-of-flight mass spectrometers (UPLC–QTOF–MS). Phytochemical profile was constituted of phenolic acids, procyanidins, quercetin derivatives and dihydrochalcones. Reducing and radical scavenging activities of individual constituents were determined using high performance liquid chromatography (HPLC) coupled to post-column FRAP and ABTS assay, respectively. Significant differences of total radical scavenging and reducing activity (expressed as trolox equivalents, TE µmol/g) were determined between the investigated cultivars. Chlorogenic acid and complex of procyanidins were the main contributors to antioxidant activity determining up to 35 % and 55 % of total TE values, respectively. Determined phenolic composition and antioxidant activity significantly depend on apple cultivars. It is important to determine the individual compounds that are significant for antioxidant activity and that could be investigated in vivo systems. The identification of the antioxidants provides information for the further research of standardized extracts that could be used for pharmaceutical preparations with specific phenolic traits.Keywords: FRAP, ABTS, antioxidant, phenolic, apples, chlorogenic acid
Procedia PDF Downloads 408445 Educational Institutional Approach for Livelihood Improvement and Sustainable Development
Authors: William Kerua
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The PNG University of Technology (Unitech) has mandatory access to teaching, research and extension education. Given such function, the Agriculture Department has established the ‘South Pacific Institute of Sustainable Agriculture and Rural Development (SPISARD)’ in 2004. SPISARD is established as a vehicle to improve farming systems practiced in selected villages by undertaking pluralistic extension method through ‘Educational Institutional Approach’. Unlike other models, SPISARD’s educational institutional approach stresses on improving the whole farming systems practiced in a holistic manner and has a two-fold focus. The first is to understand the farming communities and improve the productivity of the farming systems in a sustainable way to increase income, improve nutrition and food security as well as livelihood enhancement trainings. The second is to enrich the Department’s curriculum through teaching, research, extension and getting inputs from farming community. SPISARD has established number of model villages in various provinces in Papua New Guinea (PNG) and with many positive outcome and success stories. Adaption of ‘educational institutional approach’ thus binds research, extension and training into one package with the use of students and academic staff through model village establishment in delivering development and extension to communities. This centre (SPISARD) coordinates the activities of the model village programs and linkages. The key to the development of the farming systems is establishing and coordinating linkages, collaboration, and developing partnerships both within and external institutions, organizations and agencies. SPISARD has a six-point step strategy for the development of sustainable agriculture and rural development. These steps are (i) establish contact and identify model villages, (ii) development of model village resource centres for research and trainings, (iii) conduct baseline surveys to identify problems/needs of model villages, (iv) development of solution strategies, (v) implementation and (vi) evaluation of impact of solution programs. SPISARD envisages that the farming systems practiced being improved if the villages can be made the centre of SPISARD activities. Therefore, SPISARD has developed a model village approach to channel rural development. The model village when established become the conduit points where teaching, training, research, and technology transfer takes place. This approach is again different and unique to the existing ones, in that, the development process take place in the farmers’ environment with immediate ‘real time’ feedback mechanisms based on the farmers’ perspective and satisfaction. So far, we have developed 14 model villages and have conducted 75 trainings in 21 different areas/topics in 8 provinces to a total of 2,832 participants of both sex. The aim of these trainings is to directly participate with farmers in the pursuit to improving their farming systems to increase productivity, income and to secure food security and nutrition, thus to improve their livelihood.Keywords: development, educational institutional approach, livelihood improvement, sustainable agriculture
Procedia PDF Downloads 154444 Autism and Work, From the Perception of People Inserted in the Work
Authors: Nilson Rogério Da Silva, Ingrid Casagrande, Isabela Chicarelli Amaro Santos
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Introduction: People with Autism Spectrum Disorder (ASD) may face difficulties in social inclusion in different segments of society, especially in entering and staying at work. In Brazil, although there is legislation that equates it to the condition of disability, the number of people at work is still low. The United Nations estimates that more than 80 percent of adults with autism are jobless. In Brazil, the scenario is even more nebulous because there is no control and tracking of accurate data on the number of individuals with autism and how many of these are inserted in the labor market. Pereira and Goyos (2019) found that there is practically no scientific production about people with ASD in the labor market. Objective: To describe the experience of people with ASD inserted in the work, facilities and difficulties found in the professional exercise and the strategies used to maintain the job. Methodology: The research was approved by the Research Ethics Committee. As inclusion criteria for participation, the professional should accept to participate voluntarily, be over 18 years of age and have had some experience with the labor market. As exclusion criteria, being under 18 years of age and having never worked in a work activity. Participated in the research of 04 people with a diagnosis of ASD, aged 22 to 32 years. For data collection, an interview script was used that addressed: 1) General characteristics of the participants; 2) Family support; 3) School process; 4) Insertion in the labor market; 5) Exercise of professional activity; (6) Future and Autism; 7) Possible coping strategies. For the analysis of the data obtained, the full transcription of the interviews was performed and the technique of Content Analysis was performed. Results: The participants reported problems in different aspects: In the school environment: difficulty in social relationships, and Bullying. Lack of adaptation to the school curriculum and the structure of the classroom; In the Faculty: difficulty in following the activities, ealizar group work, meeting deadlines and establishing networking; At work: little adaptation in the work environment, difficulty in establishing good professional bonds, difficulty in accepting changes in routine or operational processes, difficulty in understanding veiled social rules. Discussion: The lack of knowledge about what disability is and who the disabled person is leads to misconceptions and negatives regarding their ability to work and in this context, people with disabilities need to constantly prove that they are able to work, study and develop as a human person, which can be classified as ableism. The adaptations and the use of technologies to facilitate the performance of people with ASD, although guaranteed in national legislation, are not always available, highlighting the difficulties and prejudice. Final Considerations: The entry and permanence of people with ASD at work still constitute a challenge to be overcome, involving changes in society in general, in companies, families and government agencies.Keywords: autism spectrum disorder (ASD), work, disability, autism
Procedia PDF Downloads 79443 CsPbBr₃@MOF-5-Based Single Drop Microextraction for in-situ Fluorescence Colorimetric Detection of Dechlorination Reaction
Authors: Yanxue Shang, Jingbin Zeng
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Chlorobenzene homologues (CBHs) are a category of environmental pollutants that can not be ignored. They can stay in the environment for a long period and are potentially carcinogenic. The traditional degradation method of CBHs is dechlorination followed by sample preparation and analysis. This is not only time-consuming and laborious, but the detection and analysis processes are used in conjunction with large-scale instruments. Therefore, this can not achieve rapid and low-cost detection. Compared with traditional sensing methods, colorimetric sensing is simpler and more convenient. In recent years, chromaticity sensors based on fluorescence have attracted more and more attention. Compared with sensing methods based on changes in fluorescence intensity, changes in color gradients are easier to recognize by the naked eye. Accordingly, this work proposes to use single drop microextraction (SDME) technology to solve the above problems. After the dechlorination reaction was completed, the organic droplet extracts Cl⁻ and realizes fluorescence colorimetric sensing at the same time. This method was integrated sample processing and visual in-situ detection, simplifying the detection process. As a fluorescence colorimetric sensor material, CsPbBr₃ was encapsulated in MOF-5 to construct CsPbBr₃@MOF-5 fluorescence colorimetric composite. Then the fluorescence colorimetric sensor was constructed by dispersing the composite in SDME organic droplets. When the Br⁻ in CsPbBr₃ exchanges with Cl⁻ produced by the dechlorination reactions, it is converted into CsPbCl₃. The fluorescence color of the single droplet of SDME will change from green to blue emission, thereby realizing visual observation. Therein, SDME can enhance the concentration and enrichment of Cl⁻ and instead of sample pretreatment. The fluorescence color change of CsPbBr₃@MOF-5 can replace the detection process of large-scale instruments to achieve real-time rapid detection. Due to the absorption ability of MOF-5, it can not only improve the stability of CsPbBr₃, but induce the adsorption of Cl⁻. Simultaneously, accelerate the exchange of Br- and Cl⁻ in CsPbBr₃ and the detection process of Cl⁻. The absorption process was verified by density functional theory (DFT) calculations. This method exhibits exceptional linearity for Cl⁻ in the range of 10⁻² - 10⁻⁶ M (10000 μM - 1 μM) with a limit of detection of 10⁻⁷ M. Whereafter, the dechlorination reactions of different kinds of CBHs were also carried out with this method, and all had satisfactory detection ability. Also verified the accuracy by gas chromatography (GC), and it was found that the SDME we developed in this work had high credibility. In summary, the in-situ visualization method of dechlorination reaction detection was a combination of sample processing and fluorescence colorimetric sensing. Thus, the strategy researched herein represents a promising method for the visual detection of dechlorination reactions and can be extended for applications in environments, chemical industries, and foods.Keywords: chlorobenzene homologues, colorimetric sensor, metal halide perovskite, metal-organic frameworks, single drop microextraction
Procedia PDF Downloads 143442 Hybrid Solutions in Physicochemical Processes for the Removal of Turbidity in Andean Reservoirs
Authors: María Cárdenas Gaudry, Gonzalo Ramces Fano Miranda
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Sediment removal is very important in the purification of water, not only for reasons of visual perception but also because of its association with odor and taste problems. The Cuchoquesera reservoir, which is in the Andean region of Ayacucho (Peru) at an altitude of 3,740 meters above sea level, visually presents suspended particles and organic impurities indicating that it contains water of dubious quality to deduce that it is suitable for direct consumption of human beings. In order to quantitatively know the degree of impurities, water quality monitoring was carried out from February to August 2018, in which four sampling stations were established in the reservoir. The selected measured parameters were electrical conductivity, total dissolved solids, pH, color, turbidity, and sludge volume. The indicators of the studied parameters exceed the permissible limits except for electrical conductivity (190 μS/cm) and total dissolved solids (255 mg/L). In this investigation, the best combination and the optimal doses of reagents were determined that allowed the removal of sediments from the waters of the Cuchoquesera reservoir, through the physicochemical process of coagulation-flocculation. In order to improve this process during the rainy season, six combinations of reagents were evaluated, made up of three coagulants (ferric chloride, ferrous sulfate, and aluminum sulfate) and two natural flocculants: prickly pear powder (Opuntia ficus-indica) and tara gum (Caesalpinia spinoza). For each combination of reagents, jar tests were developed following the central composite experimental design (CCED), where the design factors were the doses of coagulant and flocculant and the initial turbidity. The results of the jar tests were adjusted to mathematical models, obtaining that to treat the water from the Cuchoquesera reservoir, with a turbidity of 150 UTN and a color of 137 U Pt-Co, 27.9 mg/L of the coagulant aluminum sulfate with 3 mg/L of the natural tara gum flocculant to produce a purified water quality of 1.7 UTN of turbidity and 3.2 U Pt-Co of apparent color. The estimated cost of the dose of coagulant and flocculant found was 0.22 USD/m³. This is how “grey-green” technologies can be used as a combination in nature-based solutions in water treatment, in this case, to achieve potability, making it more sustainable, especially economically, if green technology is available at the site of application of the nature-based hybrid solution. This research is a demonstration of the compatibility of natural coagulants/flocculants with other treatment technologies in the integrated/hybrid treatment process, such as the possibility of hybridizing natural coagulants with other types of coagulants.Keywords: prickly pear powder, tara gum, nature-based solutions, aluminum sulfate, jar test, turbidity, coagulation, flocculation
Procedia PDF Downloads 108441 Language in International Students’ Cross-Cultural Adaptation: Case Study of Ukrainian Students in Taiwan and Lithuania
Authors: Min-Hsun Liao
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Since the outbreak of war between Russia and Ukraine in February 2022, universities around the world have extended their helping hands to welcome Ukrainian students whose academic careers have been unexpectedly interrupted. Tunghai University (THU) in Taiwan and Mykolas Romeris University (MRU) in Lithuania are among the many other universities offering short- and long-term scholarships to host Ukrainian students in the midst of the war crisis. This mixed-methods study examines the cross-cultural adjustment processes of Ukrainian students in Taiwan. The research team at MRU will also conduct a parallel study with their Ukrainian students. Both institutions are committed to gaining insights into the adjustment processes of these students through cross-institutional collaboration. Studies show that while international students come from different cultural backgrounds, the difficulties they face while studying abroad are comparable and vary in intensity. These difficulties range from learning the language of the host country, adopting cultural customs, and adapting culinary preferences to the sociocultural shock of being separated from family and friends. These problems have been the subject of numerous studies. Study findings indicate that these challenges, if not properly addressed, can lead to significant stress, despair, and failure in academics or other endeavors for international students, not to mention those who have had to leave home involuntarily and settle into a completely new environment. Among these challenges, the language of the host country is foremost. The issue of international students' adjustment, particularly language acquisition, is critical to the psychological, academic, and sociocultural well-being of individuals. Both quantitative and qualitative data will be collected: 1) the International Student Cross-cultural Adaptation Survey (ISCAS) will be distributed to all Ukrainian students in both institutions; 2) one-on-one interviews will be conducted to gain a deeper understanding of their adaptations; and 3) t-tests or ANOVA will be calculated to determine significant differences between the languages used and the adaptation patterns of Ukrainian students. The significance of this study is consistent with three SDGs, namely quality education, peace/justice, and strong institutions and partnerships for the goals. The THU and MRU research teams believe that through partnership, both institutions can benefit exponentially from sharing the data, avoiding fixed interpretation, and sharing contextual insights, which will help improve the overall quality of education for international students and promote peace/justice through strong institutions. The impact of host country language proficiency on academic and sociocultural adjustments remains inconclusive. Therefore, the outcome of the study will shed new light on the relationship between language and various adjustments. In addition, the feedback from Ukrainian students will help other host countries better serve international students who must flee their home countries for an undisturbed education.Keywords: international students, ukrainian students, cross-cultural adaptation, host country language, acculturation theory
Procedia PDF Downloads 75440 Inhibitory Effects of Crocin from Crocus sativus L. on Cell Proliferation of a Medulloblastoma Human Cell Line
Authors: Kyriaki Hatziagapiou, Eleni Kakouri, Konstantinos Bethanis, Alexandra Nikola, Eleni Koniari, Charalabos Kanakis, Elias Christoforides, George Lambrou, Petros Tarantilis
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Medulloblastoma is a highly invasive tumour, as it tends to disseminate throughout the central nervous system early in its course. Despite the high 5-year-survival rate, a significant number of patients demonstrate serious long- or short-term sequelae (e.g., myelosuppression, endocrine dysfunction, cardiotoxicity, neurological deficits and cognitive impairment) and higher mortality rates, unrelated to the initial malignancy itself but rather to the aggressive treatment. A strong rationale exists for the use of Crocus sativus L (saffron) and its bioactive constituents (crocin, crocetin, safranal) as pharmaceutical agents, as they exert significant health-promoting properties. Crocins are water soluble carotenoids. Unlike other carotenoids, crocins are highly water-soluble compounds, with relatively low toxicity as they are not stored in adipose and liver tissues. Crocins have attracted wide attention as promising anti-cancer agents, due to their antioxidant, anti-inflammatory, and immunomodulatory effects, interference with transduction pathways implicated in tumorigenesis, angiogenesis, and metastasis (disruption of mitotic spindle assembly, inhibition of DNA topoisomerases, cell-cycle arrest, apoptosis or cell differentiation) and sensitization of cancer cells to radiotherapy and chemotherapy. The current research aimed to study the potential cytotoxic effect of crocins on TE671 medulloblastoma cell line, which may be useful in the optimization of existing and development of new therapeutic strategies. Crocins were extracted from stigmas of saffron in ultrasonic bath, using petroleum-ether, diethylether and methanol 70%v/v as solvents and the final extract was lyophilized. Identification of crocins according to high-performance liquid chromatography (HPLC) analysis was determined comparing the UV-vis spectra and the retention time (tR) of the peaks with literature data. For the biological assays crocin was diluted to nuclease and protease free water. TE671 cells were incubated with a range of concentrations of crocins (16, 8, 4, 2, 1, 0.5 and 0.25 mg/ml) for 24, 48, 72 and 96 hours. Analysis of cell viability after incubation with crocins was performed with Alamar Blue viability assay. The active ingredient of Alamar Blue, resazurin, is a blue, nontoxic, cell permeable compound virtually nonfluorescent. Upon entering cells, resazurin is reduced to a pink and fluorescent molecule, resorufin. Viable cells continuously convert resazurin to resorufin, generating a quantitative measure of viability. The colour of resorufin was quantified by measuring the absorbance of the solution at 600 nm with a spectrophotometer. HPLC analysis indicated that the most abundant crocins in our extract were trans-crocin-4 and trans-crocin-3. Crocins exerted significant cytotoxicity in a dose and time-dependent manner (p < 0.005 for exposed cells to any concentration at 48, 72 and 96 hours versus cells not exposed); as their concentration and time of exposure increased, the reduction of resazurin to resofurin decreased, indicating reduction in cell viability. IC50 values for each time point were calculated ~3.738, 1.725, 0.878 and 0.7566 mg/ml at 24, 48, 72 and 96 hours, respectively. The results of our study could afford the basis of research regarding the use of natural carotenoids as anticancer agents and the shift to targeted therapy with higher efficacy and limited toxicity. Acknowledgements: The research was funded by Fellowships of Excellence for Postgraduate Studies IKY-Siemens Programme.Keywords: crocetin, crocin, medulloblastoma, saffron
Procedia PDF Downloads 216439 Validation of Global Ratings in Clinical Performance Assessment
Authors: S. J. Yune, S. Y. Lee, S. J. Im, B. S. Kam, S. Y. Baek
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This study aimed to determine the reliability of clinical performance assessments, having been emphasized by ability-based education, and professors overall assessment methods. We addressed the following problems: First, we try to find out whether there is a difference in what we consider to be the main variables affecting the clinical performance test according to the evaluator’s working period and the number of evaluation experience. Second, we examined the relationship among the global rating score (G), analytic global rating score (Gc), and the sum of the analytical checklists (C). What are the main factors affecting clinical performance assessments in relation to the numbers of times the evaluator had administered evaluations and the length of their working period service? What is the relationship between overall assessment score and analytic checklist score? How does analytic global rating with 6 components in OSCE and 4 components in sub-domains (Gc) CPX: aseptic practice, precision, systemic approach, proficiency, successfulness, and attitude overall assessment score and task-specific analytic checklist score sum (C) affect the professor’s overall global rating assessment score (G)? We studied 75 professors who attended a 2016 Bugyeoung Consortium clinical skills performances test evaluating third and fourth year medical students at the Pusan National University Medical school in South Korea (39 prof. in OSCE, 36 prof. in CPX; all consented to participate in our study). Each evaluator used 3 forms; a task-specific analytic checklist, subsequent analytic global rating scale with sub-6 domains, and overall global scale. After the evaluation, the professors responded to the questionnaire on the important factors of clinical performance assessment. The data were analyzed by frequency analysis, correlation analysis, and hierarchical regression analysis using SPSS 21.0. Their understanding of overall assessment was analyzed by dividing the subjects into groups based on experiences. As a result, they considered ‘precision’ most important in overall OSCE assessment, and ‘precise accuracy physical examination’, ‘systemic approaches to taking patient history’, and ‘diagnostic skill capability’ in overall CPX assessment. For OSCE, there was no clear difference of opinion about the main factors, but there was for CPX. Analytic global rating scale score, overall rating scale score, and analytic checklist score had meaningful mutual correlations. According to the regression analysis results, task-specific checklist score sum had the greatest effect on overall global rating. professors regarded task-specific analytic checklist total score sum as best reflecting overall OSCE test score, followed by aseptic practice, precision, systemic approach, proficiency, successfulness, and attitude on a subsequent analytic global rating scale. For CPX, subsequent analytic global rating scale score, overall global rating scale score, and task-specific checklist score had meaningful mutual correlations. These findings support explanations for validity of professors’ global rating in clinical performance assessment.Keywords: global rating, clinical performance assessment, medical education, analytic checklist
Procedia PDF Downloads 235438 Influence of Gamma-Radiation Dosimetric Characteristics on the Stability of the Persistent Organic Pollutants
Authors: Tatiana V. Melnikova, Lyudmila P. Polyakova, Alla A. Oudalova
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As a result of environmental pollution, the production of agriculture and foodstuffs inevitably contain residual amounts of Persistent Organic Pollutants (POP). The special attention must be given to organic pollutants, including various organochlorinated pesticides (OCP). Among priorities, OCP is DDT (and its metabolite DDE), alfa-HCH, gamma-HCH (lindane). The control of these substances spends proceeding from requirements of sanitary norms and rules. During too time often is lost sight of that the primary product can pass technological processing (in particular irradiation treatment) as a result of which transformation of physicochemical forms of initial polluting substances is possible. The goal of the present work was to study the OCP radiation degradation at a various gamma-radiation dosimetric characteristics. The problems posed for goal achievement: to evaluate the content of the priority of OCPs in food; study the character the degradation of OCP in model solutions (with micro concentrations commensurate with the real content of their agricultural and food products) depending upon dosimetric characteristics of gamma-radiation. Qualitative and quantitative analysis of OCP in food and model solutions by gas chromatograph Varian 3400 (Varian, Inc. (USA)); chromatography-mass spectrometer Varian Saturn 4D (Varian, Inc. (USA)) was carried out. The solutions of DDT, DDE, alpha- and gamma- isomer HCH (0.01, 0.1, 1 ppm) were irradiated on "Issledovatel" (60Co) and "Luch - 1" (60Co) installations at a dose 10 kGy with a variation of dose rate from 0.0083 up to 2.33 kGy/sec. It was established experimentally that OCP residual concentration in individual samples of food products (fish, milk, cereal crops, meat, butter) are evaluated as 10-1-10-4 mg/kg, the value of which depends on the factor-sensations territory and natural migration processes. The results were used in the preparation of model solutions OCP. The dependence of a degradation extent of OCP from a dose rate gamma-irradiation has complex nature. According to our data at a dose 10 kGy, the degradation extent of OCP at first increase passes through a maximum (over the range 0.23 – 0.43 Gy/sec), and then decrease with the magnification of a dose rate. The character of the dependence of a degradation extent of OCP from a dose rate is kept for various OCP, in polar and nonpolar solvents and does not vary at the change of concentration of the initial substance. Also in work conditions of the maximal radiochemical yield of OCP which were observed at having been certain: influence of gamma radiation with a dose 10 kGy, in a range of doses rate 0.23 – 0.43 Gy/sec; concentration initial OCP 1 ppm; use of solvent - 2-propanol after preliminary removal of oxygen. Based on, that at studying model solutions of OCP has been established that the degradation extent of pesticides and qualitative structure of OCP radiolysis products depend on a dose rate, has been decided to continue researches radiochemical transformations OCP into foodstuffs at various of doses rate.Keywords: degradation extent, dosimetric characteristics, gamma-radiation, organochlorinated pesticides, persistent organic pollutants
Procedia PDF Downloads 249437 Towards the Rapid Synthesis of High-Quality Monolayer Continuous Film of Graphene on High Surface Free Energy Existing Plasma Modified Cu Foil
Authors: Maddumage Don Sandeepa Lakshad Wimalananda, Jae-Kwan Kim, Ji-Myon Lee
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Graphene is an extraordinary 2D material that shows superior electrical, optical, and mechanical properties for the applications such as transparent contacts. Further, chemical vapor deposition (CVD) technique facilitates to synthesizing of large-area graphene, including transferability. The abstract is describing the use of high surface free energy (SFE) and nano-scale high-density surface kinks (rough) existing Cu foil for CVD graphene growth, which is an opposite approach to modern use of catalytic surfaces for high-quality graphene growth, but the controllable rough morphological nature opens new era to fast synthesis (less than the 50s with a short annealing process) of graphene as a continuous film over conventional longer process (30 min growth). The experiments were shown that high SFE condition and surface kinks on Cu(100) crystal plane existing Cu catalytic surface facilitated to synthesize graphene with high monolayer and continuous nature because it can influence the adsorption of C species with high concentration and which can be facilitated by faster nucleation and growth of graphene. The fast nucleation and growth are lowering the diffusion of C atoms to Cu-graphene interface, which is resulting in no or negligible formation of bilayer patches. High energy (500W) Ar plasma treatment (inductively Coupled plasma) was facilitated to form rough and high SFE existing (54.92 mJm-2) Cu foil. This surface was used to grow the graphene by using CVD technique at 1000C for 50s. The introduced kink-like high SFE existing point on Cu(100) crystal plane facilitated to faster nucleation of graphene with a high monolayer ratio (I2D/IG is 2.42) compared to another different kind of smooth morphological and low SFE existing Cu surfaces such as Smoother surface, which is prepared by the redeposit of Cu evaporating atoms during the annealing (RRMS is 13.3nm). Even high SFE condition was favorable to synthesize graphene with monolayer and continuous nature; It fails to maintain clean (surface contains amorphous C clusters) and defect-free condition (ID/IG is 0.46) because of high SFE of Cu foil at the graphene growth stage. A post annealing process was used to heal and overcome previously mentioned problems. Different CVD atmospheres such as CH4 and H2 were used, and it was observed that there is a negligible change in graphene nature (number of layers and continuous condition) but it was observed that there is a significant difference in graphene quality because the ID/IG ratio of the graphene was reduced to 0.21 after the post-annealing with H2 gas. Addition to the change of graphene defectiveness the FE-SEM images show there was a reduction of C cluster contamination of the surface. High SFE conditions are favorable to form graphene as a monolayer and continuous film, but it fails to provide defect-free graphene. Further, plasma modified high SFE existing surface can be used to synthesize graphene within 50s, and a post annealing process can be used to reduce the defectiveness.Keywords: chemical vapor deposition, graphene, morphology, plasma, surface free energy
Procedia PDF Downloads 244436 New Insulation Material for Solar Thermal Collectors
Authors: Nabila Ihaddadene, Razika Ihaddadene, Abdelwahaab Betka
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1973 energy crisis (rising oil prices) pushed the world to consider other alternative energy resources to existing conventional energies consisting predominantly of hydrocarbons. Renewable energies such as solar, the wind and geothermal have received renewed interest, especially to preserve nature ( the low-temperature rise of global environmental problems). Solar energy as an available, cheap and environmental friendly alternative source has various applications such as heating, cooling, drying, power generation, etc. In short, there is no life on earth without this enormous nuclear reactor, called the sun. Among available solar collector designs, flat plate collector (FPC) is low-temperature applications (heating water, space heating, etc.) due to its simple design and ease of manufacturing. Flat plate collectors are permanently fixed in position and do not track the sun (non-concentrating collectors). They operate by converting solar radiation into heat and transferring that heat to a working fluid (usually air, water, water plus antifreeze additive) flowing through them. An FPC generally consists of the main following components: glazing, absorber plate of high absorptivity, fluid tubes welded to or can be an integral part of the absorber plate, insulation and container or casing of the above-mentioned components. Insulation is of prime importance in thermal applications. There are three main families of insulation: mineral insulation; vegetal insulation and synthetic organic insulation. The old houses of the inhabitants of North Africa were built of brick made of composite material that is clay and straw. These homes are characterized by their thermal comfort; i.e. the air inside these houses is cool in summer and warm in winter. So, the material composed from clay and straw act as a thermal insulation. In this research document, the polystyrene used as insulation in the ET200 flat plate solar collector is replaced by the cheapest natural material which is clay and straw. Trials were carried out on a solar energy demonstration system (ET 200). This system contains a solar collector, water storage tank, a high power lamp simulating solar energy and a control and command cabinet. In the experimental device, the polystyrene is placed under the absorber plate and in the edges of the casing containing the components of the solar collector. In this work, we have replaced the polystyrene of the edges by the composite material. The use of the clay and straw as insulation instead of the polystyrene increases temperature difference (T2-T1) between the inlet and the outlet of the absorber by 0.9°C; thus increases the useful power transmitted to water in the solar collector. Tank Water is well heated when using the clay and straw as insulation. However, it is less heated when using the polystyrene as insulation. Clay and straw material improves also the performance of the solar collector by 5.77%. Thus, it is recommended to use this cheapest non-polluting material instead of synthetic insulation to improve the performance of the solar collector.Keywords: clay, insulation material, polystyrene, solar collector, straw
Procedia PDF Downloads 461435 Synergy Surface Modification for High Performance Li-Rich Cathode
Authors: Aipeng Zhu, Yun Zhang
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The growing grievous environment problems together with the exhaustion of energy resources put urgent demands for developing high energy density. Considering the factors including capacity, resource and environment, Manganese-based lithium-rich layer-structured cathode materials xLi₂MnO₃⋅(1-x)LiMO₂ (M = Ni, Co, Mn, and other metals) are drawing increasing attention due to their high reversible capacities, high discharge potentials, and low cost. They are expected to be one type of the most promising cathode materials for the next-generation Li-ion batteries (LIBs) with higher energy densities. Unfortunately, their commercial applications are hindered with crucial drawbacks such as poor rate performance, limited cycle life and continuous falling of the discharge potential. With decades of extensive studies, significant achievements have been obtained in improving their cyclability and rate performances, but they cannot meet the requirement of commercial utilization till now. One major problem for lithium-rich layer-structured cathode materials (LLOs) is the side reaction during cycling, which leads to severe surface degradation. In this process, the metal ions can dissolve in the electrolyte, and the surface phase change can hinder the intercalation/deintercalation of Li ions and resulting in low capacity retention and low working voltage. To optimize the LLOs cathode material, the surface coating is an efficient method. Considering the price and stability, Al₂O₃ was used as a coating material in the research. Meanwhile, due to the low initial Coulombic efficiency (ICE), the pristine LLOs was pretreated by KMnO₄ to increase the ICE. The precursor was prepared by a facile coprecipitation method. The as-prepared precursor was then thoroughly mixed with Li₂CO₃ and calcined in air at 500℃ for 5h and 900℃ for 12h to produce Li₁.₂[Ni₀.₂Mn₀.₆]O₂ (LNMO). The LNMO was then put into 0.1ml/g KMnO₄ solution stirring for 3h. The resultant was filtered and washed with water, and dried in an oven. The LLOs obtained was dispersed in Al(NO₃)₃ solution. The mixture was lyophilized to confer the Al(NO₃)₃ was uniformly coated on LLOs. After lyophilization, the LLOs was calcined at 500℃ for 3h to obtain LNMO@LMO@ALO. The working electrodes were prepared by casting the mixture of active material, acetylene black, and binder (polyvinglidene fluoride) dissolved in N-methyl-2-pyrrolidone with a mass ratio of 80: 15: 5 onto an aluminum foil. The electrochemical performance tests showed that the multiple surface modified materials had a higher initial Coulombic efficiency (84%) and better capacity retention (91% after 100 cycles) compared with that of pristine LNMO (76% and 80%, respectively). The modified material suggests that the KMnO₄ pretreat and Al₂O₃ coating can increase the ICE and cycling stability.Keywords: Li-rich materials, surface coating, lithium ion batteries, Al₂O₃
Procedia PDF Downloads 131