Search results for: I. Made Joni
Commenced in January 2007
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Edition: International
Paper Count: 7275

Search results for: I. Made Joni

585 Towards Bridging the Gap between the ESP Classroom and the Workplace: Content and Language Needs Analysis in English for an Administrative Studies Course

Authors: Vesna Vulić

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Croatia has made large steps forward in the development of higher education over the past 10 years. Purposes and objectives of the tertiary education system are focused on the personal development of young people so that they obtain competences for employment on a flexible labour market. The most frequent tensions between the tertiary institutions and employers are complaints that the current tertiary education system still supplies students with an abundance of theoretical knowledge and not enough practical skills. Polytechnics and schools of professional higher education should deliver professional education and training that will satisfy the needs of their local communities. The 21st century sets demand on undergraduates as well as their lecturers to strive for the highest standards. The skills students acquire during their studies should serve the needs of their future professional careers. In this context, teaching English for Specific Purposes (ESP) presents an enormous challenge for teachers. They have to cope with teaching the language in classes with a large number of students, limitations of time, inadequate equipment and teaching material; most frequently, this leads to focusing on specialist vocabulary neglecting the development of skills and competences required for future employment. Globalization has transformed the labour market and set new standards a perspective employee should meet. When knowledge of languages is considered, new generic skills and competences are required. Not only skillful written and oral communication is needed, but also information, media, and technology literacy, learning skills which include critical and creative thinking, collaborating and communicating, as well as social skills. The aim of this paper is to evaluate the needs of two groups of ESP first year Undergraduate Professional Administrative Study students taking ESP as a mandatory course: 47 first-year Undergraduate Professional Administrative Study students, 21 first-year employed part-time Undergraduate Professional Administrative Study students and 30 graduates with a degree in Undergraduate Professional Administrative Study with various amounts of work experience. The survey adopted a quantitative approach with the aim to determine the differences between the groups in their perception of the four language skills and different areas of law, as well as getting the insight into students' satisfaction with the current course and their motivation for studying ESP. Their perceptions will be compared to the results of the questionnaire conducted among sector professionals in order to examine how they perceive the same elements of the ESP course content and to what extent it fits into their working environment. The results of the survey indicated that there is a strong correlation between acquiring work experience and the level of importance given to particular areas of law studied in an ESP course which is in line with our initial hypothesis. In conclusion, the results of the survey should help lecturers in re-evaluating and updating their ESP course syllabi.

Keywords: English for Specific Purposes (ESP), language skills, motivation, needs analysis

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584 Methods for Early Detection of Invasive Plant Species: A Case Study of Hueston Woods State Nature Preserve

Authors: Suzanne Zazycki, Bamidele Osamika, Heather Craska, Kaelyn Conaway, Reena Murphy, Stephanie Spence

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Invasive Plant Species (IPS) are an important component of effective preservation and conservation of natural lands management. IPS are non-native plants which can aggressively encroach upon native species and pose a significant threat to the ecology, public health, and social welfare of a community. The presence of IPS in U.S. nature preserves has caused economic costs, which has estimated to exceed $26 billion a year. While different methods have been identified to control IPS, few methods have been recognized for early detection of IPS. This study examined identified methods for early detection of IPS in Hueston Woods State Nature Preserve. Mixed methods research design was adopted in this four-phased study. The first phase entailed data gathering, the phase described the characteristics and qualities of IPS and the importance of early detection (ED). The second phase explored ED methods, Geographic Information Systems (GIS) and Citizen Science were discovered as ED methods for IPS. The third phase of the study involved the creation of hotspot maps to identify likely areas for IPS growth. While the fourth phase involved testing and evaluating mobile applications that can support the efforts of citizen scientists in IPS detection. Literature reviews were conducted on IPS and ED methods, and four regional experts from ODNR and Miami University were interviewed. A questionnaire was used to gather information about ED methods used across the state. The findings revealed that geospatial methods, including Unmanned Aerial Vehicles (UAVs), Multispectral Satellites (MSS), and Normalized Difference Vegetation Index (NDVI), are not feasible for early detection of IPS, as they require GIS expertise, are still an emerging technology, and are not suitable for every habitat for the ED of IPS. Therefore, Other ED methods options were explored, which include predicting areas where IPS will grow, which can be done through monitoring areas that are like the species’ native habitat. Through literature review and interviews, IPS are known to grow in frequently disturbed areas such as along trails, shorelines, and streambanks. The research team called these areas “hotspots” and created maps of these hotspots specifically for HW NP to support and narrow the efforts of citizen scientists and staff in the ED of IPS. The results further showed that utilizing citizen scientists in the ED of IPS is feasible, especially through single day events or passive monitoring challenges. The study concluded that the creation of hotspot maps to direct the efforts of citizen scientists are effective for the early detection of IPS. Several recommendations were made, among which is the creation of hotspot maps to narrow the ED efforts as citizen scientists continues to work in the preserves and utilize citizen science volunteers to identify and record emerging IPS.

Keywords: early detection, hueston woods state nature preserve, invasive plant species, hotspots

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583 Seismotectonics and Seismology the North of Algeria

Authors: Djeddi Mabrouk

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The slow coming together between the Afro-Eurasia plates seems to be the main cause of the active deformation in the whole of North Africa which in consequence come true in Algeria with a large zone of deformation in an enough large limited band, southern through Saharan atlas and northern through tell atlas. Maghrebin and Atlassian Chain along North Africa are the consequence of this convergence. In junction zone, we have noticed a compressive regime NW-SE with a creases-faults structure and structured overthrust. From a geological point of view the north part of Algeria is younger then Saharan platform, it’s changing so unstable and constantly in movement, it’s characterized by creases openly reversed, overthrusts and reversed faults, and undergo perpetually complex movement vertically and horizontally. On structural level the north of Algeria it's a part of erogenous alpine peri-Mediterranean and essentially the tertiary age It’s spread from east to the west of Algeria over 1200 km.This oogenesis is extended from east to west on broadband of 100 km.The alpine chain is shaped by 3 domains: tell atlas in north, high plateaus in mid and Saharan atlas in the south In extreme south we find the Saharan platform which is made of Precambrian bedrock recovered by Paleozoic practically not deformed. The Algerian north and the Saharan platform are separated by an important accident along of 2000km from Agadir (Morocco) to Gabes (Tunisian). The seismic activity is localized essentially in a coastal band in the north of Algeria shaped by tell atlas, high plateaus, Saharan atlas. Earthquakes are limited in the first 20km of the earth's crust; they are caused by movements along faults of inverted orientation NE-SW or sliding tectonic plates. The center region characterizes Strong Earthquake Activity who locates mainly in the basin of Mitidja (age Neogene).The southern periphery (Atlas Blidéen) constitutes the June, more Important seism genic sources in the city of Algiers and east (Boumerdes region). The North East Region is also part of the tellian area, but it is characterized by a different strain in other parts of northern Algeria. The deformation is slow and low to moderate seismic activity. Seismic activity is related to the tectonic-slip earthquake. The most pronounced is that of 27 October 1985 (Constantine) of seismic moment magnitude Mw = 5.9. North-West region is quite active and also artificial seismic hypocenters which do not exceed 20km. The deep seismicity is concentrated mainly a narrow strip along the edge of Quaternary and Neogene basins Intra Mountains along the coast. The most violent earthquakes in this region are the earthquake of Oran in 1790 and earthquakes Orléansville (El Asnam in 1954 and 1980).

Keywords: alpine chain, seismicity north Algeria, earthquakes in Algeria, geophysics, Earth

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582 Optimization of Cobalt Oxide Conversion to Co-Based Metal-Organic Frameworks

Authors: Aleksander Ejsmont, Stefan Wuttke, Joanna Goscianska

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Gaining control over particle shape, size and crystallinity is an ongoing challenge for many materials. Especially metalorganic frameworks (MOFs) are recently widely studied. Besides their remarkable porosity and interesting topologies, morphology has proven to be a significant feature. It can affect the further material application. Thus seeking new approaches that enable MOF morphology modulation is important. MOFs are reticular structures, where building blocks are made up of organic linkers and metallic nodes. The most common strategy of ensuring metal source is using salts, which usually exhibit high solubility and hinder morphology control. However, there has been a growing interest in using metal oxides as structure-directing agents towards MOFs due to their very low solubility and shape preservation. Metal oxides can be treated as a metal reservoir during MOF synthesis. Up to now, reports in which receiving MOFs from metal oxides mostly present ZnO conversion to ZIF-8. However, there are other oxides, for instance, Co₃O₄, which often is overlooked due to their structural stability and insolubility in aqueous solutions. Cobalt-based materials are famed for catalytic activity. Therefore the development of their efficient synthesis is worth attention. In the presented work, an optimized Co₃O₄transition to Co-MOFviaa solvothermal approach was proposed. The starting point of the research was the synthesis of Co₃O₄ flower petals and needles under hydrothermal conditions using different cobalt salts (e.g., cobalt(II) chloride and cobalt(II) nitrate), in the presence of urea, and hexadecyltrimethylammonium bromide (CTAB) surfactant as a capping agent. After receiving cobalt hydroxide, the calcination process was performed at various temperatures (300–500 °C). Then cobalt oxides as a source of cobalt cations were subjected to reaction with trimesic acid in solvothermal environment and temperature of 120 °C leading to Co-MOF fabrication. The solution maintained in the system was a mixture of water, dimethylformamide, and ethanol, with the addition of strong acids (HF and HNO₃). To establish how solvents affect metal oxide conversion, several different solvent ratios were also applied. The materials received were characterized with analytical techniques, including X-ray powder diffraction, energy dispersive spectroscopy,low-temperature nitrogen adsorption/desorption, scanning, and transmission electron microscopy. It was confirmed that the synthetic routes have led to the formation of Co₃O₄ and Co-based MOF varied in shape and size of particles. The diffractograms showed receiving crystalline phase for Co₃O₄, and also for Co-MOF. The Co₃O₄ obtained from nitrates and with using low-temperature calcination resulted in smaller particles. The study indicated that cobalt oxide particles of different size influence the efficiency of conversion and morphology of Co-MOF. The highest conversion was achieved using metal oxides with small crystallites.

Keywords: Co-MOF, solvothermal synthesis, morphology control, core-shell

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581 Learners’ Preferences in Selecting Language Learning Institute (A Study in Iran)

Authors: Hoora Dehghani, Meisam Shahbazi, Reza Zare

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During the previous decade, a significant evolution has occurred in the number of private educational centers and, accordingly, the increase in the number of providers and students of these centers around the world. The number of language teaching institutes in Iran that are considered private educational sectors is also growing exponentially as the request for learning foreign languages has extremely increased in recent years. This fact caused competition among the institutions in improving better services tailored to the students’ demands to win the competition. Along with the growth in the industry of education, higher education institutes should apply the marketing-related concepts and view students as customers because students’ outlooks are similar to consumers with education. Studying the influential factors in the selection of an institute has multiple benefits. Firstly, it acknowledges the institutions of the students’ choice factors. Secondly, the institutions use the obtained information to improve their marketing methods. It also helps institutions know students’ outlooks that can be applied to expand the student know-how. Moreover, it provides practical evidence for educational centers to plan useful amenities and programs, and use efficient policies to cater to the market, and also helps them execute the methods that increase students’ feeling of contentment and assurance. Thus, this study explored the influencing factors in the selection of a language learning institute by language learners and examined and compared the importance among the varying age groups and genders. In the first phase of the study, the researchers selected 15 language learners as representative cases within the specified age ranges and genders purposefully and interviewed them to explore the comprising elements in their language institute selection process and analyzed the results qualitatively. In the second phase, the researchers identified elements as specified items of a questionnaire, and 1000 English learners across varying educational contexts rated them. The TOPSIS method was used to analyze the data quantitatively by representing the level of importance of the items for the participants generally and specifically in each subcategory; genders and age groups. The results indicated that the educational quality, teaching method, duration of training course, establishing need-oriented courses, and easy access were the most important elements. On the other hand, offering training in different languages, the specialized education of only one language, the uniform and appropriate appearance of office staff, having native professors to the language of instruction, applying Computer or online tests instead of the usual paper tests respectively as the least important choice factors in selecting a language institute. Besides, some comparisons among different groups’ ratings of choice factors were made, which revealed the differences among different groups' priorities in choosing a language institute.

Keywords: choice factors, EFL institute selection, english learning, need analysis, TOPSIS

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580 Biophysical Analysis of the Interaction of Polymeric Nanoparticles with Biomimetic Models of the Lung Surfactant

Authors: Weiam Daear, Patrick Lai, Elmar Prenner

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The human body offers many avenues that could be used for drug delivery. The pulmonary route, which is delivered through the lungs, presents many advantages that have sparked interested in the field. These advantages include; 1) direct access to the lungs and the large surface area it provides, and 2) close proximity to the blood circulation. The air-blood barrier of the alveoli is about 500 nm thick. The air-blood barrier consist of a monolayer of lipids and few proteins called the lung surfactant and cells. This monolayer consists of ~90% lipids and ~10% proteins that are produced by the alveolar epithelial cells. The two major lipid classes constitutes of various saturation and chain length of phosphatidylcholine (PC) and phosphatidylglycerol (PG) representing 80% of total lipid component. The major role of the lung surfactant monolayer is to reduce surface tension experienced during breathing cycles in order to prevent lung collapse. In terms of the pulmonary drug delivery route, drugs pass through various parts of the respiratory system before reaching the alveoli. It is at this location that the lung surfactant functions as the air-blood barrier for drugs. As the field of nanomedicine advances, the use of nanoparticles (NPs) as drug delivery vehicles is becoming very important. This is due to the advantages NPs provide with their large surface area and potential specific targeting. Therefore, studying the interaction of NPs with lung surfactant and whether they affect its stability becomes very essential. The aim of this research is to develop a biomimetic model of the human lung surfactant followed by a biophysical analysis of the interaction of polymeric NPs. This biomimetic model will function as a fast initial mode of testing for whether NPs affect the stability of the human lung surfactant. The model developed thus far is an 8-component lipid system that contains major PC and PG lipids. Recently, a custom made 16:0/16:1 PC and PG lipids were added to the model system. In the human lung surfactant, these lipids constitute 16% of the total lipid component. According to the author’s knowledge, there is not much monolayer data on the biophysical analysis of the 16:0/16:1 lipids, therefore more analysis will be discussed here. Biophysical techniques such as the Langmuir Trough is used for stability measurements which monitors changes to a monolayer's surface pressure upon NP interaction. Furthermore, Brewster Angle Microscopy (BAM) employed to visualize changes to the lateral domain organization. Results show preferential interactions of NPs with different lipid groups that is also dependent on the monolayer fluidity. Furthermore, results show that the film stability upon compression is unaffected, but there are significant changes in the lateral domain organization of the lung surfactant upon NP addition. This research is significant in the field of pulmonary drug delivery. It is shown that NPs within a certain size range are safe for the pulmonary route, but little is known about the mode of interaction of those polymeric NPs. Moreover, this work will provide additional information about the nanotoxicology of NPs tested.

Keywords: Brewster angle microscopy, lipids, lung surfactant, nanoparticles

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579 Chronic Care Management for the Medically Vulnerable during the Pandemic: Experiences of Family Caregivers of Youth with Substance Use Disorders in Zambia

Authors: Ireen Manase Kabembo, Patrick Chanda

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Background: Substance use disorders are among the chronic conditions that affect all age groups. Worldwide, there is an increase in young people affected by SUDs, which implies that more family members are transitioning into the caregiver role. Family caregivers play a buffering role in the formal healthcare system due to their involvement in caring for persons with acute and chronic conditions in the home setting. Family carers of youth with problematic alcohol and marijuana use experience myriad challenges in managing daily care for this medically vulnerable group. In addition, the poor health-seeking behaviours of youth with SUDs characterized by eluding treatment and runaway tendencies coupled with the effects of the pandemic made caregiving a daunting task for most family caregivers. Issues such as limited and unavailable psychotropic medications, social stigma and discrimination, financial hurdles, systemic barriers in adolescent and young adult mental healthcare services, and the lack of a perceived vulnerability to Covid-19 by youth with SUDs are experiences of family caretakers. Methods: A qualitative study with 30 family caregivers of youth aged 16-24 explored their lived experiences and subjective meanings using two in-depth semi-structured interviews, a caregiving timeline, and participant observation. Findings: Results indicate that most family caregivers had challenges managing care for treatment elusive youth, let alone having them adhere to Covid-19 regulations. However, youth who utilized healthcare services and adhered to treatment regimens had positive outcomes and sustained recovery. The effects of the pandemic, such as job losses and the closure of businesses, further exacerbated the financial challenges experienced by family caregivers, making it difficult to purchase needed medications and daily necessities for the youth. The unabated stigma and discrimination of families of substance-dependent youth in Zambian communities further isolated family caregivers, leaving them with limited support. Conclusion: Since young people with SUDs have a compromised mental capacity due to the cognitive impairments that come with continued substance abuse, they often have difficulties making sound judgements, including the need to utilize SUD recovery services. Also, their tendency to not adhere to the Covid-19 pandemic requirements places them at a higher risk for adverse health outcomes in the (post) pandemic era. This calls for urgent implementation of robust youth mental health services that address prevention and recovery for these emerging adults grappling with substance use disorders. Support for their family caregivers, often overlooked, cannot be overemphasized.

Keywords: chronic care management, Covid-19 pandemic, family caregivers, youth with substance use disorders

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578 Developing Motorized Spectroscopy System for Tissue Scanning

Authors: Tuba Denkceken, Ayse Nur Sarı, Volkan Ihsan Tore, Mahmut Denkceken

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The aim of the presented study was to develop a newly motorized spectroscopy system. Our system is composed of probe and motor parts. The probe part consists of bioimpedance and fiber optic components that include two platinum wires (each 25 micrometer in diameter) and two fiber cables (each 50 micrometers in diameter) respectively. Probe was examined on tissue phantom (polystyrene microspheres with different diameters). In the bioimpedance part of the probe current was transferred to the phantom and conductivity information was obtained. Adjacent two fiber cables were used in the fiber optic part of the system. Light was transferred to the phantom by fiber that was connected to the light source and backscattered light was collected with the other adjacent fiber for analysis. It is known that the nucleus expands and the nucleus-cytoplasm ratio increases during the cancer progression in the cell and this situation is one of the most important criteria for evaluating the tissue for pathologists. The sensitivity of the probe to particle (nucleus) size in phantom was tested during the study. Spectroscopic data obtained from our system on phantom was evaluated by multivariate statistical analysis. Thus the information about the particle size in the phantom was obtained. Bioimpedance and fiber optic experiments results which were obtained from polystyrene microspheres showed that the impedance value and the oscillation amplitude were increasing while the size of particle was enlarging. These results were compatible with the previous studies. In order to motorize the system within the motor part, three driver electronic circuits were designed primarily. In this part, supply capacitors were placed symmetrically near to the supply inputs which were used for balancing the oscillation. Female capacitors were connected to the control pin. Optic and mechanic switches were made. Drivers were structurally designed as they could command highly calibrated motors. It was considered important to keep the drivers’ dimension as small as we could (4.4x4.4x1.4 cm). Then three miniature step motors were connected to each other along with three drivers. Since spectroscopic techniques are quantitative methods, they yield more objective results than traditional ones. In the future part of this study, it is planning to get spectroscopic data that have optic and impedance information from the cell culture which is normal, low metastatic and high metastatic breast cancer. In case of getting high sensitivity in differentiated cells, it might be possible to scan large surface tissue areas in a short time with small steps. By means of motorize feature of the system, any region of the tissue will not be missed, in this manner we are going to be able to diagnose cancerous parts of the tissue meticulously. This work is supported by The Scientific and Technological Research Council of Turkey (TÜBİTAK) through 3001 project (115E662).

Keywords: motorized spectroscopy, phantom, scanning system, tissue scanning

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577 Evaluation of Oral Biofilm Suppression by Carribean Herbal Extracts

Authors: Ravi Teja Chitturi Suryaprakash, Chandrashekhar Unakal, Haytham Al-Bayaty, Duraisamy Saravanakumar

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Background and significance: Oral biofilm formation is a well-known causative factor for caries and periodontal diseases. Scientists over the years have been trying to find a solution against the formation of oral biofilms. Though several advances have been made to understand the microbial ecology and how the bio film survives, it is still an enigma to researchers to find a chemical product that not only can inhibit the formation of oral bio film but also not disturb the oral micro flora required for oral health and not to cause damage to the cells of the oral cavity. One such product that has never been investigated much are herbal preparations. Some of the microorganisms important in the formation of biofilm are Streptococcus mutans, Actinomyces naeslundi, Streptococuss oralis and Prevotella intermedia. The aim of this study was to study the antimicrobial property of some herbal extracts available in Trinidad and Tobago against these pathogens. The significance of this study is that identification of biologically effective plant extracts can result in indigenous development of mouth rinses and tooth pastes that the people can benefit from to not only develop effective but also a cheap solution. Methodology: The extracts from the leaves of Plectranthus ambonicus, Ocmium tenuiflorum, Azadirchata indica, Anacardium occidentale, Psidium guajava were prepared by dissolving them in water. The extracts from the roots of Curcuma longa were prepared similarly and the antimicrobial activity of these six plant extracts was determined by the agar well diffusion method using minimum inhibitory concentration (MIC) against Streptococcus mutans, Actinomyces naeslundi, Streptococuss oralis and Prevotella intermedia and compared with chlorhexidine. Results: The six plant extracts showed variable effect on the oral micro-organisms. Ocmium tenuiflorum (16.66 ± 0.44, 14 ± 0.58, 13.33 ± 0.88, 12.83 ± 0.60), Azadirchata indica (17.5 ± 0.28, 14.83 ± 0.17, 15 ± 0.58, 12.83 ± 0.6) and Curcuma longa (16.16 ± 0.44, 13.66 ± 0.88, 12.33 ± 0.88, 11.33 ± 0.67) were found to have highest inhibitory activity against all the four pathogens (Streptococcus mutans, Streptococuss oralis, Actinomyces naeslundi, and Prevotella intermedia) respectively. Conclusion: Although the extracts were not pure compounds we obtained antimicrobial results which determine that they are potent antimicrobial agents. Further derivation of pure compounds from these extracts could be lucrative as it might lead to the development of a cost effective and biologically safe medicine to act against oral biofilms. Acknowledgement: The authors would like to acknowledge the Campus Research and Publication Fund Committee, The University of the West Indies for funding this study and would also like to acknowledge Dr. Leonette Cox, Department of Chemistry, Faculty of Science and Technology, The University of the West Indies, St. Augustine Campus, Trinidad and Tobago for helping to prepare the plant extracts.

Keywords: agar well diffusion method, herbal extracts, minimum inhibitory concentration, oral biofilm forming microorganisms

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576 Gas Metal Arc Welding of Clad Plates API 5L X-60/316L Applying External Magnetic Fields during Welding

Authors: Blanca A. Pichardo, Victor H. Lopez, Melchor Salazar, Rafael Garcia, Alberto Ruiz

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Clad pipes in comparison to plain carbon steel pipes offer the oil and gas industry high corrosion resistance, reduction in economic losses due to pipeline failures and maintenance, lower labor risk, prevent pollution and environmental damage due to hydrocarbons spills caused by deteriorated pipelines. In this context, it is paramount to establish reliable welding procedures to join bimetallic plates or pipes. Thus, the aim of this work is to study the microstructure and mechanical behavior of clad plates welded by the gas metal arc welding (GMAW) process. A clad of 316L stainless steel was deposited onto API 5L X-60 plates by overlay welding with the GMAW process. Welding parameters were, 22.5 V, 271 A, heat input 1,25 kJ/mm, shielding gas 98% Ar + 2% O₂, reverse polarity, torch displacement speed 3.6 mm/s, feed rate 120 mm/s, electrode diameter 1.2 mm and application of an electromagnetic field of 3.5 mT. The overlay welds were subjected to macro-structural and microstructural characterization. After manufacturing the clad plates, a single V groove joint was machined with a 60° bevel and 1 mm root face. GMA welding of the bimetallic plates was performed in four passes with ER316L-Si filler for the root pass and an ER70s-6 electrode for the subsequent welding passes. For joining the clad plates, an electromagnetic field was applied with 2 purposes; to improve the microstructural characteristics and to assist the stability of the electric arc during welding in order to avoid magnetic arc blow. The welds were macro and microstructurally characterized and the mechanical properties were also evaluated. Vickers microhardness (100 g load for 10 s) measurements were made across the welded joints at three levels. The first profile, at the 316L stainless steel cladding, was quite even with a value of approximately 230 HV. The second microhardness profile showed high values in the weld metal, ~400 HV, this was due to the formation of a martensitic microstructure by dilution of the first welding pass with the second. The third profile crossed the third and fourth welding passes and an average value of 240 HV was measured. In the tensile tests, yield strength was between 400 to 450 MPa with a tensile strength of ~512 MPa. In the Charpy impact tests, the results were 86 and 96 J for specimens with the notch in the face and in the root of the weld bead, respectively. The results of the mechanical properties were in the range of the API 5L X-60 base material. The overlap welding process used for cladding is not suitable for large components, however, it guarantees a metallurgical bond, unlike the most commonly used processes such as thermal expansion. For welding bimetallic plates, control of the temperature gradients is key to avoid distortions. Besides, the dissimilar nature of the bimetallic plates gives rise to the formation of a martensitic microstructure during welding.

Keywords: clad pipe, dissimilar welding, gas metal arc welding, magnetic fields

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575 Blade-Coating Deposition of Semiconducting Polymer Thin Films: Light-To-Heat Converters

Authors: M. Lehtihet, S. Rosado, C. Pradère, J. Leng

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Poly(3,4-ethylene dioxythiophene) polystyrene sulfonate (PEDOT: PSS), is a polymer mixture well-known for its semiconducting properties and is widely used in the coating industry for its visible transparency and high electronic conductivity (up to 4600 S/cm) as a transparent non-metallic electrode and in organic light-emitting diodes (OLED). It also possesses strong absorption properties in the Near Infra-Red (NIR) range (λ ranging between 900 nm to 2.5 µm). In the present work, we take advantage of this absorption to explore its potential use as a transparent light-to-heat converter. PEDOT: PSS aqueous dispersions are deposited onto a glass substrate using a blade-coating technique in order to produce uniform coatings with controlled thicknesses ranging in ≈ 400 nm to 2 µm. Blade-coating technique allows us good control of the deposit thickness and uniformity by the tuning of several experimental conditions (blade velocity, evaporation rate, temperature, etc…). This liquid coating technique is a well-known, non-expensive technique to realize thin film coatings on various substrates. For coatings on glass substrates destined to solar insulation applications, the ideal coating would be made of a material able to transmit all the visible range while reflecting the NIR range perfectly, but materials possessing similar properties still have unsatisfactory opacity in the visible too (for example, titanium dioxide nanoparticles). NIR absorbing thin films is a more realistic alternative for such an application. Under solar illumination, PEDOT: PSS thin films heat up due to absorption of NIR light and thus act as planar heaters while maintaining good transparency in the visible range. Whereas they screen some NIR radiation, they also generate heat which is then conducted into the substrate that re-emits this energy by thermal emission in every direction. In order to quantify the heating power of these coatings, a sample (coating on glass) is placed in a black enclosure and illuminated with a solar simulator, a lamp emitting a calibrated radiation very similar to the solar spectrum. The temperature of the rear face of the substrate is measured in real-time using thermocouples and a black-painted Peltier sensor measures the total entering flux (sum of transmitted and re-emitted fluxes). The heating power density of the thin films is estimated from a model of the thin film/glass substrate describing the system, and we estimate the Solar Heat Gain Coefficient (SHGC) to quantify the light-to-heat conversion efficiency of such systems. Eventually, the effect of additives such as dimethyl sulfoxide (DMSO) or optical scatterers (particles) on the performances are also studied, as the first one can alter the IR absorption properties of PEDOT: PSS drastically and the second one can increase the apparent optical path of light within the thin film material.

Keywords: PEDOT: PSS, blade-coating, heat, thin-film, Solar spectrum

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574 The Importance of Development Evaluation to Preterm Children in Remote Area

Authors: Chung-Yuan Wang, Min Hsu, Bo-Ya Juan, Hsiv Ching Lin, Hsveh Min Lin, Hsiu-Fang Yeh

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The success of Taiwan's National Health Insurance (NHI) system attracts widespread praise from the international society. However, the availability of medical care in a emote area is limited. Without the convenient public transportation system and mature social welfare policy, these people are difficult to regain their health and prevent disability. Preterm children have more risk to get development delay. Preterm children in a remote area have the human right to get rehabilitation resources as those in the city area. Therefore, the aim of this study was to show the importance of development screening to preterm children in a remote area and a tract the government to notice the issue. In Pingtung, children who are suspected development delay would be suggested to take a skillful screening evaluation in our hospital. Those preterm children (within 1-year-old) visited our pediatric clinic would also be referred to take the development evaluation. After the physiatrist’s systemic evaluation, the subjects would be scheduled to take the development evaluation. Gross motor, fine motor, speech comprehension/expression and mental study were included. The evaluation was in-charged by a physical therapist, occupational therapy, speech therapist and pediatric psychologist. The tools were Peabody developmental scale, Bayley Scales of Infant and Toddler Development (Bayley-III) and Wechsler Preschool & Primary Scale of Intelligence-Revised (WPPSI-R). In 2013, 459 children received the service in our hospital. Among these children, fifty-seven were noted with preterm baby history (gestation within 37 weeks). Thirty-six of these preterm children, who had never receive development evaluation, were included in this study. Thirty-six subjects (twenty-six male and ten female) were included. Nineteen subjects were found development delay. Six subjects were found suspected development delay. In gross motor, six subjects were development delay and eight were suspected development delay. In fine motor, five subjects were development delay and three were suspected development delay. In speech, sixteen subjects were development delay and six were suspected development delay. In our study, through the provision of development evaluation service, 72.2% preterm baby were found their development delay or suspected delay. They need further early intervention rehabilitation service. We made their parents realize that when development delay was recognized at the early stage, they are often reversible. No only the patients but also their families were improved their health status. The number of the subjects was limited in our study. Further study might be needed. Compared with 770 physical therapist (PT) and 370 occupational therapy (OT) in Taipei, there are only 108 PT and 54 OT in Pingtung. Further, there are much fewer therapists working on the field of pediatric rehabilitation. Living healthy is a human's right, no matter where does he live. For those development delay children in remote area, particularly preterm children, early detection, and early intervention rehabilitation service could play an important role in decreasing their disability and improving their quality of life. Through this study, we suggest the government to add more national resources on the development evaluation to preterm children in a remote area.

Keywords: development, early intervention, preterm children, rehabilitation

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573 Promoting Incubation Support to Youth Led Enterprises: A Case Study from Bangladesh to Eradicate Hazardous Child Labour through Microfinance

Authors: Md Maruf Hossain Koli

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The issue of child labor is enormous and cannot be ignored in Bangladesh. The problem of child exploitation is a socio-economic reality of Bangladesh. This paper will indicate the causes, consequences, and possibilities of using microfinance as remedies of hazardous child labor in Bangladesh. Poverty is one of the main reasons for children to become child laborers. It is an indication of economic vulnerability, inadequate law, and enforcement system and cultural and social inequities along with the inaccessible and low-quality educational system. An attempt will be made in this paper to explore and analyze child labor scenario in Bangladesh and will explain holistic intervention of BRAC, the largest nongovernmental organization in the world to address child labor through promoting incubation support to youth-led enterprises. A combination of research methods were used to write this paper. These include non-reactive observation in the form of literature review, desk studies as well as reactive observation like site visits and, semi-structured interviews. Hazardous Child labor is a multi-dimensional and complex issue. This paper was guided by the answer following research questions to better understand the current context of hazardous child labor in Bangladesh, especially in Dhaka city. The author attempted to figure out why child labor should be considered as a development issue? Further, it also encountered why child labor in Bangladesh is not being reduced at an expected pace? And finally what could be a sustainable solution to eradicate this situation. One of the most challenging characteristics of child labor is that it interrupts a child’s education and cognitive development hence limiting the building of human capital and fostering intergenerational reproduction of poverty and social exclusion. Children who are working full-time and do not attend school, cannot develop the necessary skills. This leads them and their future generation to remain in poor socio-economic condition as they do not get a better paying job. The vicious cycle of poverty will be reproduced and will slow down sustainable development. The outcome of the research suggests that most of the parents send their children to work to help them to increase family income. In addition, most of the youth engaged in hazardous work want to get training, mentoring and easy access to finance to start their own business. The intervention of BRAC that includes classroom and on the job training, tailored mentoring, health support, access to microfinance and insurance help them to establish startup. This intervention is working in developing business and management capacity through public-private partnerships and technical consulting. Supporting entrepreneurs, improving working conditions with micro, small and medium enterprises and strengthening value chains focusing on youth and children engaged with hazardous child labor.

Keywords: child labour, enterprise development, microfinance, youth entrepreneurship

Procedia PDF Downloads 128
572 Training for Safe Tree Felling in the Forest with Symmetrical Collaborative Virtual Reality

Authors: Irene Capecchi, Tommaso Borghini, Iacopo Bernetti

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One of the most common pieces of equipment still used today for pruning, felling, and processing trees is the chainsaw in forestry. However, chainsaw use highlights dangers and one of the highest rates of accidents in both professional and non-professional work. Felling is proportionally the most dangerous phase, both in severity and frequency, because of the risk of being hit by the plant the operator wants to cut down. To avoid this, a correct sequence of chainsaw cuts must be taught concerning the different conditions of the tree. Virtual reality (VR) makes it possible to virtually simulate chainsaw use without danger of injury. The limitations of the existing applications are as follow. The existing platforms are not symmetrical collaborative because the trainee is only in virtual reality, and the trainer can only see the virtual environment on a laptop or PC, and this results in an inefficient teacher-learner relationship. Therefore, most applications only involve the use of a virtual chainsaw, and the trainee thus cannot feel the real weight and inertia of a real chainsaw. Finally, existing applications simulate only a few cases of tree felling. The objectives of this research were to implement and test a symmetrical collaborative training application based on VR and mixed reality (MR) with the overlap between real and virtual chainsaws in MR. The research and training platform was developed for the Meta quest 2 head-mounted display. The research and training platform application is based on the Unity 3D engine, and Present Platform Interaction SDK (PPI-SDK) developed by Meta. PPI-SDK avoids the use of controllers and enables hand tracking and MR. With the combination of these two technologies, it was possible to overlay a virtual chainsaw with a real chainsaw in MR and synchronize their movements in VR. This ensures that the user feels the weight of the actual chainsaw, tightens the muscles, and performs the appropriate movements during the test allowing the user to learn the correct body posture. The chainsaw works only if the right sequence of cuts is made to felling the tree. Contact detection is done by Unity's physics system, which allows the interaction of objects that simulate real-world behavior. Each cut of the chainsaw is defined by a so-called collider, and the felling of the tree can only occur if the colliders are activated in the right order simulating a safe technique felling. In this way, the user can learn how to use the chainsaw safely. The system is also multiplayer, so the student and the instructor can experience VR together in a symmetrical and collaborative way. The platform simulates the following tree-felling situations with safe techniques: cutting the tree tilted forward, cutting the medium-sized tree tilted backward, cutting the large tree tilted backward, sectioning the trunk on the ground, and cutting branches. The application is being evaluated on a sample of university students through a special questionnaire. The results are expected to test both the increase in learning compared to a theoretical lecture and the immersive and telepresence of the platform.

Keywords: chainsaw, collaborative symmetric virtual reality, mixed reality, operator training

Procedia PDF Downloads 107
571 In Search of Innovation: Exploring the Dynamics of Innovation

Authors: Michal Lysek, Mike Danilovic, Jasmine Lihua Liu

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HMS Industrial Networks AB has been recognized as one of the most innovative companies in the industrial communication industry worldwide. The creation of their Anybus innovation during the 1990s contributed considerably to the company’s success. From inception, HMS’ employees were innovating for the purpose of creating new business (the creation phase). After the Anybus innovation, they began the process of internationalization (the commercialization phase), which in turn led them to concentrate on cost reduction, product quality, delivery precision, operational efficiency, and increasing growth (the growth phase). As a result of this transformation, performing new radical innovations have become more complicated. The purpose of our research was to explore the dynamics of innovation at HMS from the aspect of key actors, activities, and events, over the three phases, in order to understand what led to the creation of their Anybus innovation, and why it has become increasingly challenging for HMS to create new radical innovations for the future. Our research methodology was based on a longitudinal, retrospective study from the inception of HMS in 1988 to 2014, a single case study inspired by the grounded theory approach. We conducted 47 interviews and collected 1 024 historical documents for our research. Our analysis has revealed that HMS’ success in creating the Anybus, and developing a successful business around the innovation, was based on three main capabilities – cultivating customer relations on different managerial and organizational levels, inspiring business relations, and balancing complementary human assets for the purpose of business creation. The success of HMS has turned the management’s attention away from past activities of key actors, of their behavior, and how they influenced and stimulated the creation of radical innovations. Nowadays, they are rhetorically focusing on creativity and innovation. All the while, their real actions put emphasis on growth, cost reduction, product quality, delivery precision, operational efficiency, and moneymaking. In the process of becoming an international company, HMS gradually refocused. In so doing they became profitable and successful, but they also forgot what made them innovative in the first place. Fortunately, HMS’ management has come to realize that this is the case and they are now in search of recapturing innovation once again. Our analysis indicates that HMS’ management is facing several barriers to innovation related path dependency and other lock-in phenomena. HMS’ management has been captured, trapped in their mindset and actions, by the success of the past. But now their future has to be secured, and they have come to realize that moneymaking is not everything. In recent years, HMS’ management have begun to search for innovation once more, in order to recapture their past capabilities for creating radical innovations. In order to unlock their managerial perceptions of customer needs and their counter-innovation driven activities and events, to utilize the full potential of their employees and capture the innovation opportunity for the future.

Keywords: barriers to innovation, dynamics of innovation, in search of excellence and innovation, radical innovation

Procedia PDF Downloads 379
570 Motivation and Constraints of Athletes’ Migration: Foreign Players in Korean Volleyball League (V-League)

Authors: Young Ik Suh, Sanghak Lee, Tywan G. Martin

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An increasing number of athletes, across all sports, are moving from their home countries to play in foreign countries. The migration of athletes, coaches, managers, and administrators within and between nations is an important aspect of the social and cultural changes taking place in modern, global sports. It is especially important to understand the context of these migrations as they are critical factors in the successful development of sports policies. In previous decades, efforts have been made to understand the motives of migrating athletes from a variety of sports, including rugby, cricket, baseball, and soccer. These studies focused on the athletes’ motivations, experiences as migrants, and recruit process. However, few studies have been conducted in order to understand athletes’ constraints of migration. The concept of constraints in leisure studies refers to the barriers that exist between an individual’s desire for participation and an individual’s real participation. The study of constraints is not a new topic in the fields of sports and recreation. In addition to understanding the motives that drive athletes to work or play in foreign countries, it is also important to recognize that negative dimensions exist that stop some athletes from migrating. Furthermore, little research has explored what makes athletes consider playing in small and unknown volleyball markets, such as the Korean Volleyball League (V-League). The V-League is a professional men’s and women’s volleyball league, started in 2005. It consists of seven men’s clubs, and six women’s clubs and each team has one foreign player. In addition, several limitations are placed on the foreign players, such as on height, position, and salary to play in the V-League. Thus, the main focus of the present research is to understand why foreign athletes (e.g., European, American, Brazil, etc.) are attracted to the V-League, which has a smaller market compared to its neighbors (i.e., China, Japan, and The Philippines). In addition, the current study seeks to identify the negative factors that prevent athletes from playing in the V-League. The participants for this study will be foreign volleyball players participating in the V-League. The investigators will provide a brief introduction to this study and inform the potential participants that they can choose whether to participate in this study. In terms of theoretical saturation, at least 12 participants are generally an adequate number to reach saturation, if they belong to a relatively homogenous group based on culture and ethnicity. This study utilizes a qualitative approach in order to understand the migration experiences foreign volleyball athletes playing in the V-League. The proposed study represents ongoing research to support work conducted by the investigators to understand the possible motivations and constraints for foreign volleyball players playing in the V-League. In addition, significant contributions to scholarship in the field of sports, psychology, and coaching studies will be an outcome of this study along with additions to the body of knowledge in several disciplines, including psychology, sociology, and social work.

Keywords: athletes’ migration, motivation, constraints, volleyball

Procedia PDF Downloads 262
569 Experimental Field for the Study of Soil-Atmosphere Interaction in Soft Soils

Authors: Andres Mejia-Ortiz, Catalina Lozada, German R. Santos, Rafael Angulo-Jaramillo, Bernardo Caicedo

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The interaction between atmospheric variables and soil properties is a determining factor when evaluating the flow of water through the soil. This interaction situation directly determines the behavior of the soil and greatly influences the changes that occur in it. The atmospheric variations such as changes in the relative humidity, air temperature, wind velocity and precipitation, are the external variables that reflect a greater incidence in the changes that are generated in the subsoil, as a consequence of the water flow in descending and ascending conditions. These environmental variations have a major importance in the study of the soil because the conditions of humidity and temperature in the soil surface depend on them. In addition, these variations control the thickness of the unsaturated zone and the position of the water table with respect to the surface. However, understanding the relationship between the atmosphere and the soil is a somewhat complex aspect. This is mainly due to the difficulty involved in estimating the changes that occur in the soil from climate changes; since this is a coupled process where act processes of mass transfer and heat. In this research, an experimental field was implemented to study in-situ the interaction between the atmosphere and the soft soils of the city of Bogota, Colombia. The soil under study consists of a 60 cm layer composed of two silts of similar characteristics at the surface and a deep soft clay deposit located under the silky material. It should be noted that the vegetal layer and organic matter were removed to avoid the evapotranspiration phenomenon. Instrumentation was carried on in situ through a field disposal of many measuring devices such as soil moisture sensors, thermocouples, relative humidity sensors, wind velocity sensor, among others; which allow registering the variations of both the atmospheric variables and the properties of the soil. With the information collected through field monitoring, the water balances were made using the Hydrus-1D software to determine the flow conditions that developed in the soil during the study. Also, the moisture profile for different periods and time intervals was determined by the balance supplied by Hydrus 1D; this profile was validated by experimental measurements. As a boundary condition, the actual evaporation rate was included using the semi-empirical equations proposed by different authors. In this study, it was obtained for the rainy periods a descending flow that was governed by the infiltration capacity of the soil. On the other hand, during dry periods. An increase in the actual evaporation of the soil induces an upward flow of water, increasing suction due to the decrease in moisture content. Also, cracks were developed accelerating the evaporation process. This work concerns to the study of soil-atmosphere interaction through the experimental field and it is a very useful tool since it allows considering all the factors and parameters of the soil in its natural state and real values of the different environmental conditions.

Keywords: field monitoring, soil-atmosphere, soft soils, soil-water balance

Procedia PDF Downloads 137
568 Exploring Barriers to Quality of Care in South African Midwifery Obstetric Units: The Perspective of Nurses and Midwives

Authors: J. Dutton, L. Knight

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Achieving quality and respectful maternal health care is part of the global agenda to improve reproductive health and achieve universal reproductive rights. Barriers to quality of care in South African maternal health facilities exist at both systemic and individual levels. Addition to this, the normalization of gender violence within South Africa has a large impact on people seeking health care as well as those who provide care within health facilities. The hierarchical environment of South Africa’s public health system penalizes both patients and providers who battle to assume any assessable power. This paper explores how systemic and individual level barriers to quality of care affect the midwifery profession within South African maternal health services and create, at times, an environment of enmity rather than care. This paper analyzes and discusses the data collected from in-depth, semi-structured interviews with nurses and midwives at three maternal health facilities in South Africa. This study has taken a holistic approach to understand the realities of nurses and midwives in order to explore the ways in which experience informs their practice and treatment of pregnant women. Through collecting and analyzing narratives, linkages between nurses and midwives day-to-day and historical experiences and disrespectful care have been made. Findings from this study show that barriers to quality of care take form in complex and interrelated ways. The physical structure of the health facility, human resource shortages, and the current model of maternal health care, which often lacks a person-centered approach, is entangled within personal beliefs and attitudes of what it means to be a midwife to create an environment that is often not conducive to a positive birthing experience. This entanglement sits within a society of high rates of violence, inequality, and poverty. Having teased out the nuances of each of these barriers and the multiple ways they reinforce each other, the findings of this paper demonstrate that birth, and the work of a midwife, are situated in a mode of discipline and punishment within this context. For analytical purposes, this paper has broken down the individual barriers to quality care and discusses the current and historical significance before returning to the interrelated forms in which barriers to quality maternal health care manifest. In conclusion this paper questions the role of agency in the ability to subvert systemic barriers to quality care and ideas around shifting attitudes and beliefs of and about midwives. International and local policies and guidelines have a role to play in realizing such shifts, however, as this paper suggests, when policy does not speak to the local context there is the risk of it contributing to frustrations and impeding the path to quality and respectful maternal health care.

Keywords: disrespect and abuse in childbirth, midwifery, South African maternal health care, quality of care

Procedia PDF Downloads 172
567 The Beauty and the Cruel: The Price of Ethics

Authors: Camila Lee Park, Mauro Fracarolli Nunes

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Understood as the preference for products and services that do not involve moral dilemmas, ethical consumption has been increasingly discussed by scholars, practitioners, and consumers. Among its diverse trends, the defense of animal rights and welfare seems to have gained particular momentum in past decades. Not surprisingly, companies, governments, ideologues, and virtually any institution or group interested in (re)shaping society invest in the building of narratives oriented to influence consumption behavior. The animal rights movement, for example, is devoted to the elimination of the use of animals in science, as well as of commercial animal agriculture and hunting activities. Although advances in ethical consumption may be observed in practice, it still seems more popular as rhetoric. Diverse scholars have addressed the disparities between self-professed ethical consumers and their actual purchase patterns, with differences being attributed to factors such as price sensitivity, lack of information, quality, cynicism, and limited availability. The gap is also linked to the 'consumer sovereignty myth', according to which consumers are only able to choose from a pre-determined range of choices made before products reach them. On the other hand, academics also debate ethical consumption behavior as more likely to occur when it assumes compliance with social norms. As sustainability becomes a permanent issue, customers may tend to adhere to ethical consumption, either because of an individual value or due to a social one. Regardless of these efforts, the actual value attributed to ethical businesses remains unclear. Likewise, the power of stakeholders’ initiatives to influence corporate strategies is dubious. In search to offer new perspectives on these matters, the present study concentrates on the following research questions: Do customers value products/companies that respect animal rights? If so, does such enhanced value convert into actions from the part of the companies? Broadly, we aim to understand if customers’ perception holds performative traits (i.e., are capable of either trigger or contribute to changes in organizational behaviour around the respect for animal rights). In addressing these issues, two preliminary behavioral vignette-based experiments were conducted, with the perspectives of 307 participants being assessed. Building on a case of the cosmetics industry, social, emotional, and functional values were hypothesized as directly impacting positive word-of-mouth, which, in turn, would carry direct effects on purchase intention. A first structural equation model was analyzed with the combined samples of studies I and II. Results suggest that emotional value strongly impacts both positive word-of-mouth and purchase intention. Data confirms initial expectations on customers valuing products and companies that comply with ethical postures concerning animals, especially if social-oriented practices are also present.

Keywords: animal rights, business ethics, emotional value, ethical consumption

Procedia PDF Downloads 119
566 Impact of Agricultural Infrastructure on Diffusion of Technology of the Sample Farmers in North 24 Parganas District, West Bengal

Authors: Saikat Majumdar, D. C. Kalita

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The Agriculture sector plays an important role in the rural economy of India. It is the backbone of our Indian economy and is the dominant sector in terms of employment and livelihood. Agriculture still contributes significantly to export earnings and is an important source of raw materials as well as of demand for many industrial products particularly fertilizers, pesticides, agricultural implements and a variety of consumer goods, etc. The performance of the agricultural sector influences the growth of Indian economy. According to the 2011 Agricultural Census of India, an estimated 61.5 percentage of rural populations are dependent on agriculture. Proper Agricultural infrastructure has the potential to transform the existing traditional agriculture into a most modern, commercial and dynamic farming system in India through its diffusion of technology. The rate of adoption of modern technology reflects the progress of development in agricultural sector. The adoption of any improved agricultural technology is also dependent on the development of road infrastructure or road network. The present study was consisting of 300 sample farmers out which 150 samples was taken from the developed area and rest 150 samples was taken from underdeveloped area. The samples farmers under develop and underdeveloped areas were collected by using Multistage Random Sampling procedure. In the first stage, North 24 Parganas District have been selected purposively. Then from the district, one developed and one underdeveloped block was selected randomly. In the third phase, 10 villages have been selected randomly from each block. Finally, from each village 15 sample farmers was selected randomly. The extents of adoption of technology in different areas were calculated through various parameters. These are percentage area under High Yielding Variety Cereals, percentage area under High Yielding Variety pulses, area under hybrids vegetables, irrigated area, mechanically operated area, amount spent on fertilizer and pesticides, etc. in both developed and underdeveloped areas of North 24 Parganas District, West Bengal. The percentage area under High Yielding Variety Cereals in the developed and underdeveloped areas was 34.86 and 22.59. 42.07 percentages and 31.46 percentages for High Yielding Variety pulses respectively. In the case the area under irrigation it was 57.66 and 35.71 percent while for the mechanically operated area it was 10.60 and 3.13 percent respectively in developed and underdeveloped areas of North 24 Parganas district, West Bengal. It clearly showed that the extent of adoption of technology was significantly higher in the developed area over underdeveloped area. Better road network system helps the farmers in increasing his farm income, farm assets, cropping intensity, marketed surplus and the rate of adoption of new technology. With this background, an attempt is made in this paper to study the impact of Agricultural Infrastructure on the adoption of modern technology in agriculture in North 24 Parganas District, West Bengal.

Keywords: agricultural infrastructure, adoption of technology, farm income, road network

Procedia PDF Downloads 101
565 Gold-Mediated Modification of Apoferritin Surface with Targeting Antibodies

Authors: Simona Dostalova, Pavel Kopel, Marketa Vaculovicova, Vojtech Adam, Rene Kizek

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Protein apoferritin seems to be a very promising structure for use as a nanocarrier. It is prepared from intracellular ferritin protein naturally found in most organisms. The role of ferritin proteins is to store and transport ferrous ions. Apoferritin is a hollow protein cage without ferrous ions that can be prepared from ferritin by reduction with thioglycolic acid or dithionite. The structure of apoferritin is composed of 24 protein subunits, creating a sphere with 12 nm in diameter. The inner cavity has a diameter of 8 nm. The drug encapsulation process is based on the response of apoferritin structure to the pH changes of surrounding solution. In low pH, apoferritin is disassembled into individual subunits and its structure is “opened”. It can then be mixed with any desired cytotoxic drug and after adjustment of pH back to neutral the subunits are reconnected again and the drug is encapsulated within the apoferritin particles. Excess drug molecules can be removed by dialysis. The receptors for apoferritin, SCARA5 and TfR1 can be found in the membrane of both healthy and cancer cells. To enhance the specific targeting of apoferritin nanocarrier, it is possible to modify its surface with targeting moieties, such as antibodies. To ensure sterically correct complex, we used a a peptide linker based on a protein G with N-terminus affinity towards Fc region of antibodies. To connect the peptide to the surface of apoferritin, the C-terminus of peptide was made of cysteine with affinity to gold. The surface of apoferritin with encapsulated doxorubicin (ApoDox) was coated either with gold nanoparticles (ApoDox-Nano) or gold (III) chloride hydrate reduced with sodium borohydride (ApoDox-HAu). The applied amount of gold in form of gold (III) chloride hydrate was 10 times higher than in the case of gold nanoparticles. However, after removal of the excess unbound ions by electrophoretic separation, the concentration of gold on the surface of apoferritin was only 6 times higher for ApoDox-HAu in comparison with ApoDox-Nano. Moreover, the reduction with sodium borohydride caused a loss of doxorubicin fluorescent properties (excitation maximum at 480 nm with emission maximum at 600 nm) and thus its biological activity. Fluorescent properties of ApoDox-Nano were similar to the unmodified ApoDox, therefore it was more suited for the intended use. To evaluate the specificity of apoferritin modified with antibodies, we used ELISA-like method with the surface of microtitration plate wells coated by the antigen (goat anti-human IgG antibodies). To these wells, we applied ApoDox without targeting antibodies and ApoDox-Nano modified with targeting antibodies (human IgG antibodies). The amount of unmodified ApoDox on antigen after incubation and subsequent rinsing with water was 5 times lower than in the case of ApoDox-Nano modified with targeting antibodies. The modification of non-gold ApoDox with antibodies caused no change in its targeting properties. It can therefore be concluded that the demonstrated procedure allows us to create nanocarrier with enhanced targeting properties, suitable for nanomedicine.

Keywords: apoferritin, doxorubicin, nanocarrier, targeting antibodies

Procedia PDF Downloads 389
564 Ambient Factors in the Perception of Crowding in Public Transport

Authors: John Zacharias, Bin Wang

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Travel comfort is increasingly seen as crucial to effecting the switch from private motorized modes to public transit. Surveys suggest that travel comfort is closely related to perceived crowding, that may involve lack of available seating, difficulty entering and exiting, jostling and other physical contacts with strangers. As found in studies on environmental stress, other factors may moderate perceptions of crowding–in this case, we hypothesize that the ambient environment may play a significant role. Travel comfort was measured by applying a structured survey to randomly selected passengers (n=369) on 3 lines of the Beijing metro on workdays. Respondents were standing with all seats occupied and with car occupancy at 14 levels. A second research assistant filmed the metro car while passengers were interviewed, to obtain the total number of passengers. Metro lines 4, 6 and 10 were selected that travel through the central city north-south, east-west and circumferentially. Respondents evaluated the following factors: crowding, noise, smell, air quality, temperature, illumination, vibration and perceived safety as they experienced them at the time of interview, and then were asked to rank these 8 factors according to their importance for their travel comfort. Evaluations were semantic differentials on a 7-point scale from highly unsatisfactory (-3) to highly satisfactory (+3). The control variables included age, sex, annual income and trip purpose. Crowding was assessed most negatively, with 41% of the scores between -3 and -2. Noise and air quality were also assessed negatively, with two-thirds of the evaluations below 0. Illumination was assessed most positively, followed by crime, vibration and temperature, all scoring at indifference (0) or slightly positive. Perception of crowding was linearly and positively related to the number of passengers in the car. Linear regression tested the impact of ambient environmental factors on perception of crowding. Noise intensity accounted for more than the actual number of individuals in the car in the perception of crowding, with smell also contributing. Other variables do not interact with the crowding variable although the evaluations are distinct. In all, only one-third of the perception of crowding (R2=.154) is explained by the number of people, with the other ambient environmental variables accounting for two-thirds of the variance (R2=.316). However, when ranking the factors by their importance to travel comfort, perceived crowding made up 69% of the first rank, followed by noise at 11%. At rank 2, smell dominates (25%), followed by noise and air quality (17%). Commuting to work induces significantly lower evaluations of travel comfort with shopping the most positive. Clearly, travel comfort is particularly important to commuters. Moreover, their perception of crowding while travelling on metro is highly conditioned by the ambient environment in the metro car. Focussing attention on the ambient environmental conditions of the metro is an effective way to address the primary concerns of travellers with overcrowding. In general, the strongly held opinions on travel comfort require more attention in the effort to induce ridership in public transit.

Keywords: ambient environment, mass rail transit, public transit, travel comfort

Procedia PDF Downloads 262
563 Developing a Tissue-Engineered Aortic Heart Valve Based on an Electrospun Scaffold

Authors: Sara R. Knigge, Sugat R. Tuladhar, Alexander Becker, Tobias Schilling, Birgit Glasmacher

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Commercially available mechanical or biological heart valve prostheses both tend to fail long-term due to thrombosis, calcific degeneration, infection, or immunogenic rejection. Moreover, these prostheses are non-viable and do not grow with the patients, which is a problem for young patients. As a result, patients often need to undergo redo-operations. Tissue-engineered (TE) heart valves based on degradable electrospun fiber scaffolds represent a promising approach to overcome these limitations. Such scaffolds need sufficient mechanical properties to withstand the hydrodynamic stress of intracardiac hemodynamics. Additionally, the scaffolds should be colonized by autologous or homologous cells to facilitate the in vivo remodeling of the scaffolds to a viable structure. This study investigates how process parameters of electrospinning and degradation affect the mechanical properties of electrospun scaffolds made of FDA-approved, biodegradable polymer polycaprolactone (PCL). Fiber mats were produced from a PCL/tetrafluoroethylene solution by electrospinning. The e-spinning process was varied in terms of scaffold thickness, fiber diameter, fiber orientation, and fiber interconnectivity. The morphology of the fiber mats was characterized with a scanning electron microscope (SEM). The mats were degraded in different solutions (cell culture media, SBF, PBS and 10 M NaOH-Solution). At different time points of degradation (2, 4 and 6 weeks), tensile and cyclic loading tests were performed. Fresh porcine pericardium and heart valves served as a control for the mechanical assessment. The progression of polymer degradation was quantified by SEM and differential scanning calorimetry (DSC). Primary Human aortic endothelial cells (HAECs) and Human induced pluripotent stem cell-derived endothelial cells (iPSC-ECs) were seeded on the fiber mats to investigate the cell colonization potential. The results showed that both the electrospinning parameters and the degradation significantly influenced the mechanical properties. Especially the fiber orientation has a considerable impact and leads to a pronounced anisotropic behavior of the scaffold. Preliminary results showed that the polymer became strongly more brittle over time. However, the embrittlement can initially only be detected in the mechanical test. In the SEM and DSC investigations, neither morphological nor thermodynamic changes are significantly detectable. Live/Dead staining and SEM imaging of the cell-seeded scaffolds showed that HAECs and iPSC-ECs were able to grow on the surface of the polymer. In summary, this study's results indicate a promising approach to the development of a TE aortic heart valve based on an electrospun scaffold.

Keywords: electrospun scaffolds, long-term polymer degradation, mechanical behavior of electrospun PCL, tissue engineered aortic heart valve

Procedia PDF Downloads 143
562 The Development of Modernist Chinese Architecture from the Perspective of Cultural Regionalism in Taiwan: Spatial Practice by the Fieldoffice Architects

Authors: Yilei Yu

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Modernism, emerging in the Western world of the 20th century, attempted to create a universal international style, which pulled the architectural and social systems created by classicism back to an initial pure state. However, out of the introspection of the Modernism, Regionalism attempted to restore a humanistic environment and create flexible buildings during the 1950s. Meanwhile, as the first generation of architects came back, the wind of the Regionalism blew to Taiwan. However, with the increasing of political influence and the tightening of free creative space, from the second half of the 1950s to the 1980s, the "real" Regional Architecture, which should have taken roots in Taiwan, becomes the "fake" Regional Architecture filled with the oriental charm. Through the Comparative Method, which includes description, interpretation, juxtaposition, and comparison, this study analyses the difference of the style of the Modernist Chinese Architecture between the period before the 1980s and the after. The paper aims at exploring the development of Regionalism Architecture in Taiwan, which includes three parts. First, the burgeoning period of the "modernist Chinese architecture" in Taiwan was the beginning of the Chinese Nationalist Party's coming to Taiwan to consolidate political power. The architecture of the "Ming and Qing Dynasty Palace Revival Style" dominated the architectural circles in Taiwan. These superficial "regional buildings" have nearly no combination with the local customs of Taiwan, which is difficult to evoke the social identity. Second, in the late 1970s, the second generation of architects headed by Baode Han began focusing on the research and preservation of traditional Taiwanese architecture, and creating buildings combined the terroirs of Taiwan through the imitation of styles. However, some scholars have expressed regret that very few regionalist architectural works that appeared in the 1980s can respond specifically to regional conditions and forms of construction. Instead, most of them are vocabulary-led representations. Third, during the 1990s, by the end of the period of martial law, community building gradually emerged, which made the object of Taiwan's architectural concern gradually extended to the folk and ethnic groups. In the Yilan area, there are many architects who care about the local environment, such as the Field office Architects. Compared with the hollow regionality of the passionate national spirits that emerged during the martial law period, the local practice of the architect team in Yilan can better link the real local environmental life and reflect the true regionality. In conclusion, with the local practice case of the huge construction team in Yilan area, this paper focuses on the Spatial Practice by the Field office Architects to explore the spatial representation of the space and the practical enlightenment in the process of modernist Chinese architecture development in Taiwan.

Keywords: regionalism, modernism, Chinese architecture, political landscape, spatial representation

Procedia PDF Downloads 129
561 Measurement of Influence of the COVID-19 Pandemic on Efficiency of Japan’s Railway Companies

Authors: Hideaki Endo, Mika Goto

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The global outbreak of the COVID-19 pandemic has seriously affected railway businesses. The number of railway passengers decreased due to the decline in the number of commuters and business travelers to avoid crowded trains and a sharp drop in inbound tourists visiting Japan. This has affected not only railway businesses but also related businesses, including hotels, leisure businesses, and retail businesses at station buildings. In 2021, the companies were divided into profitable and loss-making companies. This division suggests that railway companies, particularly loss-making companies, needed to decrease operational inefficiency. To measure the impact of COVID-19 and discuss the sustainable management strategies of railway companies, we examine the cost inefficiency of Japanese listed railway companies by applying stochastic frontier analysis (SFA) to their operational and financial data. First, we employ the stochastic frontier cost function approach to measure inefficiency. The cost frontier function is formulated as a Cobb–Douglas type, and we estimated parameters and variables for inefficiency. This study uses panel data comprising 26 Japanese-listed railway companies from 2005 to 2020. This period includes several events deteriorating the business environment, such as the financial crisis from 2007 to 2008 and the Great East Japan Earthquake of 2011, and we compare those impacts with those of the COVID-19 pandemic after 2020. Second, we identify the characteristics of the best-practice railway companies and examine the drivers of cost inefficiencies. Third, we analyze the factors influencing cost inefficiency by comparing the profiles of the top 10 railway companies and others before and during the pandemic. Finally, we examine the relationship between cost inefficiency and the implementation of efficiency measures for each railway company. We obtained the following four findings. First, most Japanese railway companies showed the lowest cost inefficiency (most efficient) in 2014 and the highest in 2020 (least efficient) during the COVID-19 pandemic. The second worst occurred in 2009 when it was affected by the financial crisis. However, we did not observe a significant impact of the 2011 Great East Japan Earthquake. This is because no railway company was influenced by the earthquake in this operating area, except for JR-EAST. Second, the best-practice railway companies are KEIO and TOKYU. The main reason for their good performance is that both operate in and near the Tokyo metropolitan area, which is densely populated. Third, we found that non-best-practice companies had a larger decrease in passenger kilometers than best-practice companies. This indicates that passengers made fewer long-distance trips because they refrained from inter-prefectural travel during the pandemic. Finally, we found that companies that implement more efficiency improvement measures had higher cost efficiency and they effectively used their customer databases through proactive DX investments in marketing and asset management.

Keywords: COVID-19 pandemic, stochastic frontier analysis, railway sector, cost efficiency

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560 Methodology to Assess the Circularity of Industrial Processes

Authors: Bruna F. Oliveira, Teresa I. Gonçalves, Marcelo M. Sousa, Sandra M. Pimenta, Octávio F. Ramalho, José B. Cruz, Flávia V. Barbosa

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The EU Circular Economy action plan, launched in 2020, is one of the major initiatives to promote the transition into a more sustainable industry. The circular economy is a popular concept used by many companies nowadays. Some industries are better forwarded to this reality than others, and the tannery industry is a sector that needs more attention due to its strong environmental impact caused by its dimension, intensive resources consumption, lack of recyclability, and second use of its products, as well as the industrial effluents generated by the manufacturing processes. For these reasons, the zero-waste goal and the European objectives are further being achieved. In this context, a need arises to provide an effective methodology that allows to determine the level of circularity of tannery companies. Regarding the complexity of the circular economy concept, few factories have a specialist in sustainability to assess the company’s circularity or have the ability to implement circular strategies that could benefit the manufacturing processes. Although there are several methodologies to assess circularity in specific industrial sectors, there is not an easy go-to methodology applied in factories aiming for cleaner production. Therefore, a straightforward methodology to assess the level of circularity, in this case of a tannery industry, is presented and discussed in this work, allowing any company to measure the impact of its activities. The methodology developed consists in calculating the Overall Circular Index (OCI) by evaluating the circularity of four key areas -energy, material, economy and social- in a specific factory. The index is a value between 0 and 1, where 0 means a linear economy, and 1 is a complete circular economy. Each key area has a sub-index, obtained through key performance indicators (KPIs) regarding each theme, and the OCI reflects the average of the four sub-indexes. Some fieldwork in the appointed company was required in order to obtain all the necessary data. By having separate sub-indexes, one can observe which areas are more linear than others. Thus, it is possible to work on the most critical areas by implementing strategies to increase the OCI. After these strategies are implemented, the OCI is recalculated to check the improvements made and any other changes in the remaining sub-indexes. As such, the methodology in discussion works through continuous improvement, constantly reevaluating and improving the circularity of the factory. The methodology is also flexible enough to be implemented in any industrial sector by adapting the KPIs. This methodology was implemented in a selected Portuguese small and medium-sized enterprises (SME) tannery industry and proved to be a relevant tool to measure the circularity level of the factory. It was witnessed that it is easier for non-specialists to evaluate circularity and identify possible solutions to increase its value, as well as learn how one action can impact their environment. In the end, energetic and environmental inefficiencies were identified and corrected, increasing the sustainability and circularity of the company. Through this work, important contributions were provided, helping the Portuguese SMEs to achieve the European and UN 2030 sustainable goals.

Keywords: circular economy, circularity index, sustainability, tannery industry, zero-waste

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559 Speech Acts of Selected Classroom Encounters: Analyzing the Speech Acts of a Career Technology Lesson

Authors: Michael Amankwaa Adu

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Effective communication in the classroom plays a vital role in ensuring successful teaching and learning. In particular, the types of language and speech acts teachers use shape classroom interactions and influence student engagement. This study aims to analyze the speech acts employed by a Career Technology teacher in a junior high school. While much research has focused on speech acts in language classrooms, less attention has been given to how these acts operate in non-language subject areas like technical education. The study explores how different types of speech acts—directives, assertives, expressives, and commissives—are used during three classroom encounters: lesson introduction, content delivery, and classroom management. This research seeks to fill the gap in understanding how teachers of non-language subjects use speech acts to manage classroom dynamics and facilitate learning. The study employs a mixed-methods design, combining qualitative and quantitative approaches. Data was collected through direct classroom observation and audio recordings of a one-hour Career Technology lesson. The transcriptions of the lesson were analyzed using John Searle’s taxonomy of speech acts, classifying the teacher’s utterances into directives, assertives, expressives, and commissives. Results show that directives were the most frequently used speech act, accounting for 59.3% of the teacher's utterances. These speech acts were essential in guiding student behavior, giving instructions, and maintaining classroom control. Assertives made up 20.4% of the speech acts, primarily used for stating facts and reinforcing content. Expressives, at 14.2%, expressed emotions such as approval or frustration, helping to manage the emotional atmosphere of the classroom. Commissives were the least used, representing 6.2% of the speech acts, often used to set expectations or outline future actions. No declarations were observed during the lesson. The findings of this study reveal the critical role that speech acts play in managing classroom behavior and delivering content in technical subjects. Directives were crucial for ensuring students followed instructions and completed tasks, while assertives helped in reinforcing lesson objectives. Expressives contributed to motivating or disciplining students, and commissives, though less frequent, helped set clear expectations for students’ future actions. The absence of declarations suggests that the teacher prioritized guiding students over making formal pronouncements. These insights can inform teaching strategies across various subject areas, demonstrating that a diverse use of speech acts can create a balanced and interactive learning environment. This study contributes to the growing field of pragmatics in education and offers practical recommendations for educators, particularly in non-language classrooms, on how to utilize speech acts to enhance both classroom management and student engagement.

Keywords: classroom interaction, pragmatics, speech acts, teacher communication, career technology

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558 Identification and Quantification of Lisinopril from Pure, Formulated and Urine Samples by Micellar Thin Layer Chromatography

Authors: Sudhanshu Sharma

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Lisinopril, 1-[N-{(s)-I-carboxy-3 phenyl propyl}-L-proline dehydrate is a lysine analog of enalaprilat, the active metabolite of enalapril. It is long-acting, non-sulhydryl angiotensin-converting enzyme (ACE) inhibitor that is used for the treatment of hypertension and congestive heart failure in daily dosage 10-80 mg. Pharmacological activity of lisinopril has been proved in various experimental and clinical studies. Owing to its importance and widespread use, efforts have been made towards the development of simple and reliable analytical methods. As per our literature survey, lisinopril in pharmaceutical formulations has been determined by various analytical methodologies like polaragraphy, potentiometry, and spectrophotometry, but most of these analytical methods are not too suitable for the Identification of lisinopril from clinical samples because of the interferences caused by the amino acids and amino groups containing metabolites present in biological samples. This report is an attempt in the direction of developing a simple and reliable method for on plate identification and quantification of lisinopril in pharmaceutical formulations as well as from human urine samples using silica gel H layers developed with a new mobile phase comprising of micellar solutions of N-cetyl-N, N, N-trimethylammonium bromide (CTAB). Micellar solutions have found numerous practical applications in many areas of separation science. Micellar liquid chromatography (MLC) has gained immense popularity and wider applicability due to operational simplicity, cost effectiveness, relatively non-toxicity and enhanced separation efficiency, low aggressiveness. Incorporation of aqueous micellar solutions as mobile phase was pioneered by Armstrong and Terrill as they accentuated the importance of TLC where simultaneous separation of ionic or non-ionic species in a variety of matrices is required. A peculiarity of the micellar mobile phases (MMPs) is that they have no macroscopic analogues, as a result the typical separations can be easily achieved by using MMPs than aqueous organic mobile phases. Previously MMPs were successfully employed in TLC based critical separations of aromatic hydrocarbons, nucleotides, vitamin K1 and K5, o-, m- and p- aminophenol, amino acids, separation of penicillins. The human urine analysis for identification of selected drugs and their metabolites has emerged as an important investigation tool in forensic drug analysis. Among all chromatographic methods available only thin layer chromatography (TLC) enables a simple fast and effective separation of the complex mixtures present in various biological samples and is recommended as an approved testing for forensic drug analysis by federal Law. TLC proved its applicability during successful separation of bio-active amines, carbohydrates, enzymes, porphyrins, and their precursors, alkaloid and drugs from urine samples.

Keywords: lisnopril, surfactant, chromatography, micellar solutions

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557 Preparation of Activated Carbon From Waste Feedstock: Activation Variables Optimization and Influence

Authors: Oluwagbemi Victor Aladeokin

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In the last decade, the global peanut cultivation has seen increased demand, which is attributed to their health benefits, rising to ~ 41.4 MMT in 2019/2020. Peanut and other nutshells are considered as waste in various parts of the world and are usually used for their fuel value. However, this agricultural by-product can be converted to a higher value product such as activated carbon. For many years, due to the highly porous structure of activated carbon, it has been widely and effectively used as an adsorbent in the purification and separation of gases and liquids. Those used for commercial purposes are primarily made from a range of precursors such as wood, coconut shell, coal, bones, etc. However, due to difficulty in regeneration and high cost, various agricultural residues such as rice husk, corn stalks, apricot stones, almond shells, coffee beans, etc, have been explored to produce activated carbons. In the present study, the potential of peanut shells as precursors in the production of activated carbon and their adsorption capacity is investigated. Usually, precursors used to produce activated carbon have carbon content above 45 %. A typical raw peanut shell has 42 wt.% carbon content. To increase the yield, this study has employed chemical activation method using zinc chloride. Zinc chloride is well known for its effectiveness in increasing porosity of porous carbonaceous materials. In chemical activation, activation temperature and impregnation ratio are parameters commonly reported to be the most significant, however, this study has also studied the influence of activation time on the development of activated carbon from peanut shells. Activated carbons are applied for different purposes, however, as the application of activated carbon becomes more specific, an understanding of the influence of activation variables to have a better control of the quality of the final product becomes paramount. A traditional approach to experimentally investigate the influence of the activation parameters, involves varying each parameter at a time. However, a more efficient way to reduce the number of experimental runs is to apply design of experiment. One of the objectives of this study is to optimize the activation variables. Thus, this work has employed response surface methodology of design of experiment to study the interactions between the activation parameters and consequently optimize the activation parameters (temperature, impregnation ratio, and activation time). The optimum activation conditions found were 485 °C, 15 min and 1.7, temperature, activation time, and impregnation ratio respectively. The optimum conditions resulted in an activated carbon with relatively high surface area ca. 1700 m2/g, 47 % yield, relatively high density, low ash, and high fixed carbon content. Impregnation ratio and temperature were found to mostly influence the final characteristics of the produced activated carbon from peanut shells. The results of this study, using response surface methodology technique, have revealed the potential and the most significant parameters that influence the chemical activation process, of peanut shells to produce activated carbon which can find its use in both liquid and gas phase adsorption applications.

Keywords: chemical activation, fixed carbon, impregnation ratio, optimum, surface area

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556 Liquefaction Phenomenon in the Kathmandu Valley during the 2015 Earthquake of Nepal

Authors: Kalpana Adhikari, Mandip Subedi, Keshab Sharma, Indra P. Acharya

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The Gorkha Nepal earthquake of moment magnitude (Mw) 7.8 struck the central region of Nepal on April 25, 2015 with the epicenter about 77 km northwest of Kathmandu Valley . Peak ground acceleration observed during the earthquake was 0.18g. This motion induced several geotechnical effects such as landslides, foundation failures liquefaction, lateral spreading and settlement, and local amplification. An aftershock of moment magnitude (Mw) 7.3 hit northeast of Kathmandu on May 12 after 17 days of main shock caused additional damages. Kathmandu is the largest city in Nepal, have a population over four million. As the Kathmandu Valley deposits are composed mainly of sand, silt and clay layers with a shallow ground water table, liquefaction is highly anticipated. Extensive liquefaction was also observed in Kathmandu Valley during the 1934 Nepal-Bihar earthquake. Field investigations were carried out in Kathmandu Valley immediately after Mw 7.8, April 25 main shock and Mw 7.3, May 12 aftershock. Geotechnical investigation of both liquefied and non-liquefied sites were conducted after the earthquake. This paper presents observations of liquefaction and liquefaction induced damage, and the liquefaction potential assessment based on Standard Penetration Tests (SPT) for liquefied and non-liquefied sites. SPT based semi-empirical approach has been used for evaluating liquefaction potential of the soil and Liquefaction Potential Index (LPI) has been used to determine liquefaction probability. Recorded ground motions from the event are presented. Geological aspect of Kathmandu Valley and local site effect on the occurrence of liquefaction is described briefly. Observed liquefaction case studies are described briefly. Typically, these are sand boils formed by freshly ejected sand forced out of over-pressurized sub-strata. At most site, sand was ejected to agricultural fields forming deposits that varied from millimetres to a few centimeters thick. Liquefaction-induced damage to structures in these areas was not significant except buildings on some places tilted slightly. Boiled soils at liquefied sites were collected and the particle size distributions of ejected soils were analyzed. SPT blow counts and the soil profiles at ten liquefied and non-liquefied sites were obtained. The factors of safety against liquefaction with depth and liquefaction potential index of the ten sites were estimated and compared with observed liquefaction after 2015 Gorkha earthquake. The liquefaction potential indices obtained from the analysis were found to be consistent with the field observation. The field observations along with results from liquefaction assessment were compared with the existing liquefaction hazard map. It was found that the existing hazard maps are unrepresentative and underestimate the liquefaction susceptibility in Kathmandu Valley. The lessons learned from the liquefaction during this earthquake are also summarized in this paper. Some recommendations are also made to the seismic liquefaction mitigation in the Kathmandu Valley.

Keywords: factor of safety, geotechnical investigation, liquefaction, Nepal earthquake

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