Search results for: health social work
6515 Knowledge Attitude and Practices of COVID-19 among Tamil Nadu Residence
Authors: Shivanand Pawar
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In India, a collective range of measurements had been adopted to control the massive spread of the COVID-19 pandemic, but World Health Organization (2022) revealed 525 930 fatalities and 43,847,065 confirmed cases. There are currently 30,857 cases per million people. Lack of knowledge, attitude and practices are the main causes thought to be increased COVID-19. The present study aims to assess the knowledge, attitude, and practice among Tamil Nadu residents. The participants (N=332) were aged 20 to 50 (mean=42.78, & SD=13.98) and were selected using purposive sampling, and data were collected online using knowledge, attitude and practice scale. Data were analyzed using person correlation and multiple regression analysis. The result found that 31.30% had satisfactory knowledge, 68.70% had non-satisfactory knowledge, followed by 45.20% had a positive attitude, 54.80% had a negative attitude, and 34.30% had a good practice, and 65.70% had poor practice towards COVID-19. Correlation results revealed that age has a negative and significant relationship with Knowledge and Practice towards COVID-19. The current study results contribute to the existing literature on knowledge, attitude and practice of COVID-19 to reduce the COVID-19 cases by managing unhealthy knowledge, attitude and practice to control the massive spread of COVID-19.Keywords: COVID-19, knowledge, practice, attitude, Fisherman community
Procedia PDF Downloads 1076514 The Influence of Phosphate Fertilizers on Radiological Situation of Cultivated Lands: ²¹⁰Po, ²²⁶Ra, ²³²Th, ⁴⁰K and ¹³⁷Cs Concentrations in Soil
Authors: Grzegorz Szaciłowski, Marta Konop, Małgorzata Dymecka, Jakub Ośko
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In 1996, the European Council Directive 96/29/EURATOM pointed phosphate fertilizers to have a potentially negative influence on the environment from the radiation protection point of view. Fertilizers along with irrigation and crop rotation were the milestones that allowed to increase agricultural productivity. Firstly based on natural materials such as compost, manure, fish processing waste, etc., and since the 19th century created synthetically, fertilizers caused a boom in crop yield and helped to propel global food production, especially after World War II. In this work the concentrations of ²¹⁰Po, ²²⁶Ra, ²³²Th, ⁴⁰K, and ¹³⁷Cs in selected fertilizers and soil samples were determined. The results were used to calculate the annual addition of natural radionuclides and increment of the external radiation exposure caused by the use of studied fertilizers. Soils intended for different types of crops were sampled in early spring when no vegetation had occurred yet. Analysed fertilizers were those with which the soil was previously fertilized. For gamma radionuclides, a high purity germanium detector GX3520 from Canberra was used. The polonium concentration was determined by radiochemical separation followed by measurement by means of alpha spectrometry. The spectrometer used in this study was equipped with 450 cm² PIPS detector from Canberra. Obtained results showed significant differences in radionuclide composition between phosphate and nitrogenous fertilizers (e.g. the radium equivalent activity for phosphate fertilizer was 207.7 Bq/kg in comparison to <5.6 Bq/kg for nitrogenous fertilizer). The calculated increase of external radiation exposure due to use of phosphate fertilizer ranged between 3.4 and 5.4 nG/h, which represents up to 10% of the polish average outdoor exposure due to terrestrial gamma radiation (45 nGy/h).Keywords: ²¹⁰Po, alpha spectrometry, exposure, gamma spectrometry, phosphate fertilizer, soil
Procedia PDF Downloads 2926513 The Relationship between Spindle Sound and Tool Performance in Turning
Authors: N. Seemuang, T. McLeay, T. Slatter
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Worn tools have a direct effect on the surface finish and part accuracy. Tool condition monitoring systems have been developed over a long period and used to avoid a loss of productivity resulting from using a worn tool. However, the majority of tool monitoring research has applied expensive sensing systems not suitable for production. In this work, the cutting sound in turning machine was studied using microphone. Machining trials using seven cutting conditions were conducted until the observable flank wear width (FWW) on the main cutting edge exceeded 0.4 mm. The cutting inserts were removed from the tool holder and the flank wear width was measured optically. A microphone with built-in preamplifier was used to record the machining sound of EN24 steel being face turned by a CNC lathe in a wet cutting condition using constant surface speed control. The sound was sampled at 50 kS/s and all sound signals recorded from microphone were transformed into the frequency domain by FFT in order to establish the frequency content in the audio signature that could be then used for tool condition monitoring. The extracted feature from audio signal was compared to the flank wear progression on the cutting inserts. The spectrogram reveals a promising feature, named as ‘spindle noise’, which emits from the main spindle motor of turning machine. The spindle noise frequency was detected at 5.86 kHz of regardless of cutting conditions used on this particular CNC lathe. Varying cutting speed and feed rate have an influence on the magnitude of power spectrum of spindle noise. The magnitude of spindle noise frequency alters in conjunction with the tool wear progression. The magnitude increases significantly in the transition state between steady-state wear and severe wear. This could be used as a warning signal to prepare for tool replacement or adapt cutting parameters to extend tool life.Keywords: tool wear, flank wear, condition monitoring, spindle noise
Procedia PDF Downloads 3296512 Strengths and Weaknesses of Tally, an LCA Tool for Comparative Analysis
Authors: Jacob Seddlemeyer, Tahar Messadi, Hongmei Gu, Mahboobeh Hemmati
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The main purpose of this first tier of the study is to quantify and compare the embodied environmental impacts associated with alternative materials applied to Adohi Hall, a residence building at the University of Arkansas campus, Fayetteville, AR. This 200,000square foot building has5 stories builtwith mass timber and is compared to another scenario where the same edifice is built with a steel frame. Based on the defined goal and scope of the project, the materials respectivetothe respective to the two building options are compared in terms of Global Warming Potential (GWP), starting from cradle to the construction site, which includes the material manufacturing stage (raw material extract, process, supply, transport, and manufacture) plus transportation to the site (module A1-A4, based on standard EN 15804 definition). The consumedfossil fuels and emitted CO2 associated with the buildings are the major reason for the environmental impacts of climate change. In this study, GWP is primarily assessed to the exclusion of other environmental factors. The second tier of this work is to evaluate Tally’s performance in the decision-making process through the design phases, as well as determine its strengths and weaknesses. Tally is a Life Cycle Assessment (LCA) tool capable of conducting a cradle-to-grave analysis. As opposed to other software applications, Tally is specifically targeted at buildings LCA. As a peripheral application, this software tool is directly run within the core modeling application platform called Revit. This unique functionality causes Tally to stand out from other similar tools in the building sector LCA analysis. The results of this study also provide insights for making more environmentally efficient decisions in the building environment and help in the move forward to reduce Green House Gases (GHGs) emissions and GWP mitigation.Keywords: comparison, GWP, LCA, materials, tally
Procedia PDF Downloads 2196511 Interdisciplinary Collaborative Innovation Mechanism for Sustainability Challenges
Authors: C. Park, H. Lee, Y-J. Lee
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Aim: This study presents Interdisciplinary Collaborative Innovation Mechanism as a medium to enable the effective generation of innovations for sustainability challenges facing humanities. Background: Interdisciplinary approach of fusing disparate knowledge and perspectives from diverse expertise and subject areas is one of the key requirements to address the intricate nature of sustainability issues. There is a lack of rigorous empirical study of the systematic structure of interdisciplinary collaborative innovation for sustainability to date. Method: To address this research gap, the action research approach is adopted to develop the Interdisciplinary Collaborative Innovation Mechanism (ICIM) framework based on an empirical study of a total of 28 open innovation competitions in the format of MAKEathons between 2016 to 2023. First, the conceptual framework was formulated based on the literature findings, and the framework was subsequently tested and iterated. Outcomes: The findings provide the ICIM framework composed of five elements: Discipline Diversity Quadruple; Systematic Structure; Inspirational Stimuli; Supportive Collaboration Environment; and Hardware and Intellectual Support. The framework offers a discussion of the key elements when attempting to facilitate interdisciplinary collaboration for sustainability innovation. Contributions: This study contributes to two burgeoning areas of sustainable development and open innovation studies by articulating the concrete structure to bridge the gap. In practice, the framework helps facilitate effective innovation processes and positive social and environmental impact created for real-world sustainability challenges.Keywords: action research, interdisciplinary collaboration, open innovation, problem-solving, sustainable development, sustainability challenges
Procedia PDF Downloads 2396510 Modelling the Effect of Psychological Capital on Climate Change Adaptation among Smallholders from South Africa
Authors: Unity Chipfupa, Aluwani Tagwi, Edilegnaw Wale
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Climate change adaptation studies are challenged by a limited understanding of how non-cognitive factors such as psychological capital affect adaptation decisions of smallholder farmers. The concept of psychological capital has not been fully applied in the empirical literature on climate change adaptation strategies. Hence, the study was meant to assess how psychological capital endowment affects climate change adaptation among smallholder farmers. A multivariate probit regression model was estimated using data collected from 328 smallholder farmers in KwaZulu-Natal, South Africa. The findings indicate that, among other factors, self-confidence and hope or aspirations in farming influence climate change adaptation decisions of smallholders. The psychological capital theory proved to be comprehensive in identifying specific psychological dimensions associated with adaptation decisions. However, the non-alignment of approaches for measuring non-cognitive factors made it difficult to compare results among different studies. In conclusion, the study recommends the need for practical ways for enhancing smallholders’ endowment with key non-cognitive abilities. Researchers should develop and agree on a comprehensive framework for assessing non-cognitive factors critical for climate change adaptation. This will improve the use of positive psychology theories to advance the literature on climate change adaptation. Other key recommendations include targeted support for communities facing higher risks of climate change, improving smallholders’ ability to adapt, promotion of social networks and the inclusion of farming objectives as an important indicator in climate change adaptation research.Keywords: adaptive capacity, climate change adaptation, psychological capital, multivariate probit, non-cognitive factors.
Procedia PDF Downloads 1396509 Manage an Acute Pain Unit based on the Balanced Scorecard
Authors: Helena Costa Oliveira, Carmem Oliveira, Rita Moutinho
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The Balanced Scorecard (BSC) is a continuous strategic monitoring model focused not only on financial issues but also on internal processes, patients/users, and learning and growth. Initially dedicated to business management, it currently serves organizations of other natures - such as hospitals. This paper presents a BSC designed for a Portuguese Acute Pain Unit (APU). This study is qualitative and based on the experience of collaborators at the APU. The management of APU is based on four perspectives – users, internal processes, learning and growth, and financial and legal. For each perspective, there were identified strategic objectives, critical factors, lead indicators and initiatives. The strategic map of the APU outlining sustained strategic relations among strategic objectives. This study contributes to the development of research in the health management area as it explores how organizational insufficiencies and inconsistencies in this particular case can be addressed, through the identification of critical factors, to clearly establish core outcomes and initiatives to set up.Keywords: acute pain unit, balanced scorecard, hospital management, organizational performance, Portugal
Procedia PDF Downloads 1406508 Clustering Using Cooperative Multihop Mini-Groups in Wireless Sensor Network: A Novel Approach
Authors: Virender Ranga, Mayank Dave, Anil Kumar Verma
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Recently wireless sensor networks (WSNs) are used in many real life applications like environmental monitoring, habitat monitoring, health monitoring etc. Due to power constraint cheaper devices used in these applications, the energy consumption of each device should be kept as low as possible such that network operates for longer period of time. One of the techniques to prolong the network lifetime is an intelligent grouping of sensor nodes such that they can perform their operation in cooperative and energy efficient manner. With this motivation, we propose a novel approach by organize the sensor nodes in cooperative multihop mini-groups so that the total global energy consumption of the network can be reduced and network lifetime can be improved. Our proposed approach also reduces the number of transmitted messages inside the WSNs, which further minimizes the energy consumption of the whole network. The experimental simulations show that our proposed approach outperforms over the state-of-the-art approach in terms of stability period and aggregated data.Keywords: clustering, cluster-head, mini-group, stability period
Procedia PDF Downloads 3496507 Magnetic Chloromethylated Polymer Nanocomposite for Selective Pollutant Removal
Authors: Fabio T. Costa, Sergio E. Moya, Marcelo H. Sousa
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Nanocomposites designed by embedding magnetic nanoparticles into a polymeric matrix stand out as ideal magnetic-hybrid and magneto-responsive materials as sorbents for removal of pollutants in environmental applications. Covalent coupling is often desired for the immobilization of species on these nanocomposites, in order to keep them permanently bounded, not desorbing or leaching over time. Moreover, unwanted adsorbates can be separated by successive washes/magnetic separations, and it is also possible to recover the adsorbate covalently bound to the nanocomposite surface through detaching/cleavage protocols. Thus, in this work, we describe the preparation and characterization of highly-magnetizable chloromethylated polystyrene-based nanocomposite beads for selective covalent coupling in environmental applications. For synthesis optimization, acid resistant core-shelled maghemite (γ-Fe₂O₃) nanoparticles were coated with oleate molecules and directly incorporated into the organic medium during a suspension polymerization process. Moreover, the cross-linking agent ethylene glycol dimethacrylate (EGDMA) was utilized for co-polymerization with the 4-vinyl benzyl chloride (VBC) to increase the resistance of microbeads against leaching. After characterizing samples with XRD, ICP-OES, TGA, optical, SEM and TEM microscopes, a magnetic composite consisting of ~500 nm-sized cross-linked polymeric microspheres embedding ~8 nm γ-Fe₂O₃ nanoparticles was verified. This nanocomposite showed large room temperature magnetization (~24 emu/g) due to the high content in maghemite (~45 wt%) and resistance against leaching even in acidic media. Moreover, the presence of superficial chloromethyl groups, probed by FTIR and XPS spectroscopies and confirmed by an amination test can selectively adsorb molecules through the covalent coupling and be used in molecular separations as shown for the selective removal of 4-aminobenzoic acid from a mixture with benzoic acid.Keywords: nanocomposite, magnetic nanoparticle, covalent separation, pollutant removal
Procedia PDF Downloads 1056506 Organism Profile Causing Prosthetic Joint Infection Continues to Evolve
Authors: Bahaa Eldin Kornah
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The organism profile for peri-prosthetic joint infection caused by hematogenous seeding or direct inoculations is changing. The organisms that cause prosthetic joint infections range from normal skin colonizers to highly virulent pathogens. The pathogens continue to evolve. While Staphylococcus aureus continues to be the leading organism, gram-negative bacilli account for approximately 7% of cases and that incidence is increasing. Methicillin-resistant S. aureus(MRSA) accounts for approximately 10% of all infections occurring in the community setting and 20% of those in the health care setting. The list of organisms causing PJI has expanded in recent years. It is important to have an understanding of which organisms may be causing a periprosthetic joint infection based on where the patient contracted it and their recent medical history. Also, recent technology has expanded rapidly and new methods to detect the pathogen and why we failed in detecting it. There are a number of explanations for the latter finding, perhaps the most important reason being the liberal use of antibiotics that interferes with the isolation of the infective organism.Keywords: infection, periprosthetic, hip, organism profile, joint infection, joint infection
Procedia PDF Downloads 786505 Tourism and Hospitality Education Efficiency Management: The Case of the Tourism Department of Sultan Qaboos University
Authors: Tamer Mohamed Atef
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The tourism and hospitality education is a branch of the overall tourism and hospitality industry that is dedicated to providing the industry with well-educated, well-trained, skilled, enthusiastic and committed workforce. The Tourism Department at the College of Arts and Social Sciences (Sultan Qaboos University), Oman, has been providing the Omani society with undergraduate tourism and hospitality educational services since Fall 2001. Despite the fact that Tourism Department graduates are not facing any employment concerns, fluctuation in the number of enrollees and graduates, however, has been a significant characteristic since the inception of the program. To address this concern, several tactical and strategic decisions have been made, notably that the program has received accreditation from two prestigious international accreditation institutions, which mark two major milestones in the educational journey of the Tourism Department. The current study, thus, aims to provide a tourism and hospitality education efficiency management model. To achieve this aim, the following objectives were identified: to analyze students in - graduates out matrix, and to assess graduates’ employment trends. A survey was conducted to assess the current employment status of the department graduates. Secondary data were collected from Deanship of Admission and Registration statistical reports on the Tourism Department. Data were tabulated and analyzed in such a way that set forth the major findings from the survey and the secondary data. This study sheds light on the educational system created and followed by the Tourism Department, in an effort to provide a tourism and hospitality education efficiency management model, that would help educators and administrators better manage their programs.Keywords: tourism, hospitality, education, students, graduates, employability, indicators
Procedia PDF Downloads 3426504 The Prevalence of Soil Transmitted Helminths among Newly Arrived Expatriate Labors in Jeddah, Saudi Arabia
Authors: Mohammad Al-Refai, Majed Wakid
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Introduction: Soil-transmitted diseases (STD) are caused by intestinal worms that are transmitted via various routes into the human body resulting in various clinical manifestations. The intestinal worms causing these infections are known as soil transmitted helminths (STH), including Hook worms, Ascaris lumbricoides (A. lumbricoides), Trichuris trichiura (T. trichiura), and Strongyloides sterocoralis (S. sterocoralis). Objectives: The aim of this study was to investigate the prevalence of STH among newly arrived expatriate labors in Jeddah city, Saudi Arabia, using three different techniques (direct smears, sedimentation concentration, and real-time PCR). Methods: A total of 188 stool specimens were collected and investigated at the parasitology laboratory in the Special Infectious Agents Unit at King Fahd Medical Research Center, King Abdulaziz University in Jeddah, Saudi Arabia. Microscopic examination of wet mount preparations using normal saline and Lugols Iodine was carried out, followed by the formal ether sedimentation method. In addition, real-time PCR was used as a molecular tool to detect several STH and hookworm speciation. Results: Out of 188 stool specimens analyzed, in addition to STH parasite, several other types were detected. 9 samples (4.79%) were positive for Entamoeba coli, 7 samples (3.72%) for T. trichiura, 6 samples (3.19%) for Necator americanus, 4 samples (2.13%) for S. sterocoralis, 4 samples (2.13%) for A. lumbricoides, 4 samples (2.13%) for E. histolytica, 3 samples (1.60%) for Blastocystis hominis, 2 samples (1.06%) for Ancylostoma duodenale, 2 samples (1.06%) for Giardia lamblia, 1 sample (0.53%) for Iodamoeba buetschlii, 1 sample (0.53%) for Hymenolepis nana, 1 sample (0.53%) for Endolimax nana, and 1 sample (0.53%) for Heterophyes heterophyes. Out of the 35 infected cases, 26 revealed single infection, 8 with double infections, and only one triple infection of different STH species and other intestinal parasites. Higher rates of STH infections were detected among housemaids (11 cases) followed by drivers (7 cases) when compared to other occupations. According to educational level, illiterate participants represent the majority of infected workers (12 cases). The majority of workers' positive cases were from the Philippines. In comparison between laboratory techniques, out of the 188 samples screened for STH, real-time PCR was able to detect the DNA in (19/188) samples followed by Ritchie sedimentation technique (18/188), and direct wet smear (7/188). Conclusion: STH infections are a major public health issue to healthcare systems around the world. Communities must be educated on hygiene practices and the severity of such parasites to human health. As far as drivers and housemaids come to close contact with families, including children and elderlies. This may put family members at risk of developing serious side effects related to STH, especially as the majority of workers were illiterate, lacking the basic hygiene knowledge and practices. We recommend the official authority in Jeddah and around the kingdom of Saudi Arabia to revise the standard screening tests for newly arrived workers and enforce regular follow-up inspections to minimize the chances of the spread of STH from expatriate workers to the public.Keywords: expatriate labors, Jeddah, prevalence, soil transmitted helminths
Procedia PDF Downloads 1416503 Effect of Different Thermomechanical Cycles on Microstructure of AISI 4140 Steel
Authors: L.L. Costa, A. M. G. Brito, S. Khan, L. Schaeffer
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Microstructure resulting from the forging process is studied as a function of variables such as temperature, deformation, austenite grain size and cooling rate. The purpose of this work is to study the thermomechanical behavior of DIN 42CrMo4 (AISI 4140) steel maintained at the temperatures of 900°, 1000°, 1100° and 1200°C for the austenization times of 22, 66 and 200 minutes each and subsequently forged. These samples were quenched in water in order to study the austenite grain and to investigate the microstructure instead of quenching the annealed samples after forging they were cooled down naturally in the air. The morphologies and properties of the materials such as hardness; prepared by these two different routes have been compared. In addition to the forging experiments, the numerical simulation using the finite element model (FEM), microhardness profiles and metallography images have been presented. Forging force vs position curves has been compared with metallographic results for each annealing condition. The microstructural phenomena resulting from the hot conformation proved that longer austenization time and higher temperature decrease the forging force in the curves. The complete recrystallization phenomenon (static, dynamic and meta dynamic) was observed at the highest temperature and longest time i.e., the samples austenized for 200 minutes at 1200ºC. However, higher hardness of the quenched samples was obtained when the temperature was 900ºC for 66 minutes. The phases observed in naturally cooled samples were exclusively ferrite and perlite, but the continuous cooling diagram indicates the presence of austenite and bainite. The morphology of the phases of naturally cooled samples has shown that the phase arrangement and the previous austenitic grain size are the reasons to high hardness in obtained samples when temperature were 900ºC and 1100ºC austenization times of 22 and 66 minutes, respectively.Keywords: austenization time, thermomechanical effects, forging process, steel AISI 4140
Procedia PDF Downloads 1416502 Detailed Degradation-Based Model for Solid Oxide Fuel Cells Long-Term Performance
Authors: Mina Naeini, Thomas A. Adams II
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Solid Oxide Fuel Cells (SOFCs) feature high electrical efficiency and generate substantial amounts of waste heat that make them suitable for integrated community energy systems (ICEs). By harvesting and distributing the waste heat through hot water pipelines, SOFCs can meet thermal demand of the communities. Therefore, they can replace traditional gas boilers and reduce greenhouse gas (GHG) emissions. Despite these advantages of SOFCs over competing power generation units, this technology has not been successfully commercialized in large-scale to replace traditional generators in ICEs. One reason is that SOFC performance deteriorates over long-term operation, which makes it difficult to find the proper sizing of the cells for a particular ICE system. In order to find the optimal sizing and operating conditions of SOFCs in a community, a proper knowledge of degradation mechanisms and effects of operating conditions on SOFCs long-time performance is required. The simplified SOFC models that exist in the current literature usually do not provide realistic results since they usually underestimate rate of performance drop by making too many assumptions or generalizations. In addition, some of these models have been obtained from experimental data by curve-fitting methods. Although these models are valid for the range of operating conditions in which experiments were conducted, they cannot be generalized to other conditions and so have limited use for most ICEs. In the present study, a general, detailed degradation-based model is proposed that predicts the performance of conventional SOFCs over a long period of time at different operating conditions. Conventional SOFCs are composed of Yttria Stabilized Zirconia (YSZ) as electrolyte, Ni-cermet anodes, and LaSr₁₋ₓMnₓO₃ (LSM) cathodes. The following degradation processes are considered in this model: oxidation and coarsening of nickel particles in the Ni-cermet anodes, changes in the pore radius in anode, electrolyte, and anode electrical conductivity degradation, and sulfur poisoning of the anode compartment. This model helps decision makers discover the optimal sizing and operation of the cells for a stable, efficient performance with the fewest assumptions. It is suitable for a wide variety of applications. Sulfur contamination of the anode compartment is an important cause of performance drop in cells supplied with hydrocarbon-based fuel sources. H₂S, which is often added to hydrocarbon fuels as an odorant, can diminish catalytic behavior of Ni-based anodes by lowering their electrochemical activity and hydrocarbon conversion properties. Therefore, the existing models in the literature for H₂-supplied SOFCs cannot be applied to hydrocarbon-fueled SOFCs as they only account for the electrochemical activity reduction. A regression model is developed in the current work for sulfur contamination of the SOFCs fed with hydrocarbon fuel sources. The model is developed as a function of current density and H₂S concentration in the fuel. To the best of authors' knowledge, it is the first model that accounts for impact of current density on sulfur poisoning of cells supplied with hydrocarbon-based fuels. Proposed model has wide validity over a range of parameters and is consistent across multiple studies by different independent groups. Simulations using the degradation-based model illustrated that SOFCs voltage drops significantly in the first 1500 hours of operation. After that, cells exhibit a slower degradation rate. The present analysis allowed us to discover the reason for various degradation rate values reported in literature for conventional SOFCs. In fact, the reason why literature reports very different degradation rates, is that literature is inconsistent in definition of how degradation rate is calculated. In the literature, the degradation rate has been calculated as the slope of voltage versus time plot with the unit of voltage drop percentage per 1000 hours operation. Due to the nonlinear profile of voltage over time, degradation rate magnitude depends on the magnitude of time steps selected to calculate the curve's slope. To avoid this issue, instantaneous rate of performance drop is used in the present work. According to a sensitivity analysis, the current density has the highest impact on degradation rate compared to other operating factors, while temperature and hydrogen partial pressure affect SOFCs performance less. The findings demonstrated that a cell running at lower current density performs better in long-term in terms of total average energy delivered per year, even though initially it generates less power than if it had a higher current density. This is because of the dominant and devastating impact of large current densities on the long-term performance of SOFCs, as explained by the model.Keywords: degradation rate, long-term performance, optimal operation, solid oxide fuel cells, SOFCs
Procedia PDF Downloads 1256501 A Case Study on Performance of Isolated Bridges under Near-Fault Ground Motion
Authors: Daniele Losanno, H. A. Hadad, Giorgio Serino
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This paper presents a numerical investigation on the seismic performance of a benchmark bridge with different optimal isolation systems under near fault ground motion. Usually, very large displacements make seismic isolation an unfeasible solution due to boundary conditions, especially in case of existing bridges or high risk seismic regions. Hence, near-fault ground motions are most likely to affect either structures with long natural period range like isolated structures or structures sensitive to velocity content such as viscously damped structures. The work is aimed at analyzing the seismic performance of a three-span continuous bridge designed with different isolation systems having different levels of damping. The case study was analyzed in different configurations including: (a) simply supported, (b) isolated with lead rubber bearings (LRBs), (c) isolated with rubber isolators and 10% classical damping (HDLRBs), and (d) isolated with rubber isolators and 70% supplemental damping ratio. Case (d) represents an alternative control strategy that combines the effect of seismic isolation with additional supplemental damping trying to take advantages from both solutions. The bridge is modeled in SAP2000 and solved by time history direct-integration analyses under a set of six recorded near-fault ground motions. In addition to this, a set of analysis under Italian code provided seismic action is also conducted, in order to evaluate the effectiveness of the suggested optimal control strategies under far field seismic action. Results of the analysis demonstrated that an isolated bridge equipped with HDLRBs and a total equivalent damping ratio of 70% represents a very effective design solution for both mitigation of displacement demand at the isolation level and base shear reduction in the piers also in case of near fault ground motion.Keywords: isolated bridges, near-fault motion, seismic response, supplemental damping, optimal design
Procedia PDF Downloads 2796500 Development and Characterization of Multiphase Hydrogel Systems for Wound Healing
Authors: Rajendra Jangde, Deependra Singh
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Present work was based with objective to release of the antimicrobial and debriding agent in sustained manner at the wound surface. In order to provide a long-lasting antimicrobial action and moist environment on wound space, Biocompatible moist system was developed for complete healing. In the present study, a biocompatible moist system of PVA-gelatin hydrogel was developed capable of carrying multiple drugs- Quercetin and Cabopol in controlled manner for effective and complete wound healing. Carbopol and Quercetin were prepared by thin film hydration techniques and optimized system was incorporated in PVA-Gelatin slurry. PVA-Gelatin hydrogels were prepared by freeze thaw method. The prepared dispersion was casted into films to prepare multiphase hydrogel system and characterized by in vitro and in vivo studies. Results revealed the uniform dispersion of microspheres in a three-dimensional matrix of the PVA-Gelatin hydrogel observed at different magnifications. The in vitro release data showed typical biphasic release pattern, i.e., a burst release followed by a slower sustained release for 5 days. Prepared system was found to be stable under both normal and accelerated conditions. Histopathological study showed significant (p<0.05) increase in fibroblast cells, collagen fibres and blood vessels formation. All parameters such as wound contraction, tensile strength, histopathological and biochemical parameters- hydroxyproline content, protein level, etc. were observed significant (p<0.05) in comparison to control group. Present results suggest an accelerated re-epithelialization under moist wound environment with delivery of multiple drugs effective at different stages of wound healing cascade with minimum disturbance of wound bed.Keywords: multiphase hydrogel, optimization quercetin, wound healing
Procedia PDF Downloads 2376499 The Triad Experience: Benefits and Drawbacks of the Paired Placement of Student Teachers in Physical Education
Authors: Todd Pennington, Carol Wilkinson, Keven Prusak
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Traditional models of student teaching practices typically involve the placement of a student teacher with an experienced mentor teacher. However, due to the ever-decreasing number of quality placements, an alternative triad approach is the paired placement of student teachers with one mentor teacher in a community of practice. This study examined the paired-placement of student teachers in physical education to determine the benefits and drawbacks after a 14-week student teaching experience. PETE students (N = 22) at a university in the United States were assigned to work in a triad with a student teaching partner and a mentor teacher, making up eleven triads for the semester. The one exception was a pair that worked for seven weeks at an elementary school and then for seven weeks at a junior high school, thus having two mentor teachers and participating in two triads. A total of 12 mentor teachers participated in the study. All student teachers and mentor teachers volunteered and agreed to participate. The student teaching experience was structured so that students engaged in: (a) individual teaching (one teaching the lesson with the other observing), (b) co-planning, and (c) peer coaching. All students and mentor teachers were interviewed at the conclusion of the experience. Using interview data, field notes, and email response data, the qualitative data was analyzed using the constant comparative method. The benefits of the paired placement experience emerged into three categories (a) quality feedback, (b) support, and (c) collaboration. The drawbacks emerged into four categories (a) unrealistic experience, (b) laziness in preparation, (c) lack of quality feedback, and (d) personality mismatch. Recommendations include: providing in-service training prior to student teaching to optimize the triad experience, ongoing seminars throughout the experience specifically designed for triads, and a hybrid model of paired placement for the first half of student teaching followed by solo student teaching for the second half of the experience.Keywords: community of practice, paired placement, physical education, student teaching
Procedia PDF Downloads 3946498 Drought Risk Analysis Using Neural Networks for Agri-Businesses and Projects in Lejweleputswa District Municipality, South Africa
Authors: Bernard Moeketsi Hlalele
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Drought is a complicated natural phenomenon that creates significant economic, social, and environmental problems. An analysis of paleoclimatic data indicates that severe and extended droughts are inevitable part of natural climatic circle. This study characterised drought in Lejweleputswa using both Standardised Precipitation Index (SPI) and neural networks (NN) to quantify and predict respectively. Monthly 37-year long time series precipitation data were obtained from online NASA database. Prior to the final analysis, this dataset was checked for outliers using SPSS. Outliers were removed and replaced by Expectation Maximum algorithm from SPSS. This was followed by both homogeneity and stationarity tests to ensure non-spurious results. A non-parametric Mann Kendall's test was used to detect monotonic trends present in the dataset. Two temporal scales SPI-3 and SPI-12 corresponding to agricultural and hydrological drought events showed statistically decreasing trends with p-value = 0.0006 and 4.9 x 10⁻⁷, respectively. The study area has been plagued with severe drought events on SPI-3, while on SPI-12, it showed approximately a 20-year circle. The concluded the analyses with a seasonal analysis that showed no significant trend patterns, and as such NN was used to predict possible SPI-3 for the last season of 2018/2019 and four seasons for 2020. The predicted drought intensities ranged from mild to extreme drought events to come. It is therefore recommended that farmers, agri-business owners, and other relevant stakeholders' resort to drought resistant crops as means of adaption.Keywords: drought, risk, neural networks, agri-businesses, project, Lejweleputswa
Procedia PDF Downloads 1176497 Process of Analysis, Evaluation and Verification of the 'Real' Redevelopment of the Public Open Space at the Neighborhood’s Stairs: Case Study of Serres, Greece
Authors: Ioanna Skoufali
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The present study is directed towards adaptation to climate change closely related to the phenomenon of the urban heat island (UHI). This issue is widespread and common to different urban realities, but particularly in Mediterranean cities that are characterized by dense urban. The attention of this work of redevelopment of the open space is focused on mitigation techniques aiming to solve local problems such as microclimatic parameters and the conditions of thermal comfort in summer, related to urban morphology. This quantitative analysis, evaluation, and verification survey involves the methodological elaboration applied in a real study case by Serres, through the experimental support of the ENVImet Pro V4.1 and BioMet software developed: i) in two phases concerning the anteoperam (phase a1 # 2013) and the post-operam (phase a2 # 2016); ii) in scenario A (+ 25% of green # 2017). The first study tends to identify the main intervention strategies, namely: the application of cool pavements, the increase of green surfaces, the creation of water surface and external fans; moreover, it obtains the minimum results achieved by the National Program 'Bioclimatic improvement project for public open space', EPPERAA (ESPA 2007-2013) related to the four environmental parameters illustrated below: the TAir = 1.5 o C, the TSurface = 6.5 o C, CDH = 30% and PET = 20%. In addition, the second study proposes a greater potential for improvement than postoperam intervention by increasing the vegetation within the district towards the SW/SE. The final objective of this in-depth design is to be transferable in homogeneous cases of urban regeneration processes with obvious effects on the efficiency of microclimatic mitigation and thermal comfort.Keywords: cool pavements, microclimate parameters (TAir, Tsurface, Tmrt, CDH), mitigation strategies, outdoor thermal comfort (PET & UTCI)
Procedia PDF Downloads 1956496 Legal Theories Underpinning Access to Justice for Victims of Sexual Violence in Refugee Camps in Africa
Authors: O. E. Eberechi, G. P. Stevens
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Legal theory has been referred to as the explanation of why things do or do not happen. It also describes situations and why they ensue. It provides a normative framework by which things are regulated and a foundation for the establishment of legal mechanisms/institutions that can bring about a desired change in a society. Furthermore, it offers recommendations in resolving practical problems and describes what the law is, what the law ought to be and defines the legal landscape generally. Some legal theories provide a universal standard, e.g. human rights, while others are capable of organizing and streamlining the collective use, and, by extension, bring order to society. Legal theory is used to explain how the world works and how it does not work. This paper will argue for the application of the principles of legal theory in the achievement of access to justice for female victims of sexual violence in refugee camps in Africa through the analysis of legal theories underpinning the access to justice for these women. It is a known fact that female refugees in camps in Africa often experience some form of sexual violation. The perpetrators of these incidents may never be apprehended, prosecuted, convicted or sentenced. Where prosecution does occur, the perpetrators are either acquitted as a result of poor investigation, inept prosecution, a lack of evidence, or the case may be dismissed owing to tardiness on the part of the prosecutor, which accounts for the culture of impunity in refugee camps. In other words, victims do not have access to the justice that could ameliorate the plight of the victims. There is, thus, a need for a legal framework that will facilitate access to justice for these victims. This paper will start with an introduction, and be followed by the definition of legal theory, its functions and its application in law. Secondly, it will provide a brief explanation of the problems faced by female refugees who are victims of sexual violence in refugee camps in Africa. Thirdly, it will embark on an analysis of theories which will be a help to an understanding of the precarious situation of female refugees, why they are violated, the need for access to justice for these victims, and the principles of legal theory in its usefulness in resolving access to justice for these victims.Keywords: access to justice, underpinning legal theory, refugee, sexual violence
Procedia PDF Downloads 4246495 Viscoelastic Characterization of Gelatin/Cellulose Nanocrystals Aqueous Bionanocomposites
Authors: Liliane Samara Ferreira Leite, Francys Kley Vieira Moreira, Luiz Henrique Capparelli Mattoso
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The increasing environmental concern regarding the plastic pollution worldwide has stimulated the development of low-cost biodegradable materials. Proteins are renewable feedstocks that could be used to produce biodegradable plastics. Gelatin, for example, is a cheap film-forming protein extracted from animal skin and connective tissues of Brazilian Livestock residues; thus it has a good potential in low-cost biodegradable plastic production. However, gelatin plastics are limited in terms of mechanical and barrier properties. Cellulose nanocrystals (CNC) are efficient nanofillers that have been used to extend physical properties of polymers. This work was aimed at evaluating the reinforcing efficiency of CNC on gelatin films. Specifically, we have employed the continuous casting as the processing method for obtaining the gelatin/CNC bionanocomposites. This required a first rheological study for assessing the effect of gelatin-CNC and CNC-CNC interactions on the colloidal state of the aqueous bionanocomposite formulations. CNC were isolated from eucalyptus pulp by sulfuric acid hydrolysis (65 wt%) at 55 °C for 30 min. Gelatin was solubilized in ultra-pure water at 85°C for 20 min and then mixed with glycerol at 20 wt.% and CNC at 0.5 wt%, 1.0 wt% and 2.5 wt%. Rotational measurements were performed to determine linear viscosity (η) of bionanocomposite solutions, which increased with increasing CNC content. At 2.5 wt% CNC, η increased by 118% regarding the neat gelatin solution, which was ascribed to percolation CNC network formation. Storage modulus (G’) and loss modulus (G″) further determined by oscillatory tests revealed that a gel-like behavior was dominant in the bionanocomposite solutions (G’ > G’’) over a broad range of temperature (20 – 85 °C), particularly at 2.5 wt% CNC. These results confirm effective interactions in the aqueous gelatin-CNC bionanocomposites that could substantially increase the physical properties of the gelatin plastics. Tensile tests are underway to confirm this hypothesis. The authors would like to thank the Fapesp (process n 2016/03080-3) for support.Keywords: bionanocomposites, cellulose nanocrystals, gelatin, viscoelastic characterization
Procedia PDF Downloads 1476494 Agile Software Effort Estimation Using Regression Techniques
Authors: Mikiyas Adugna
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Effort estimation is among the activities carried out in software development processes. An accurate model of estimation leads to project success. The method of agile effort estimation is a complex task because of the dynamic nature of software development. Researchers are still conducting studies on agile effort estimation to enhance prediction accuracy. Due to these reasons, we investigated and proposed a model on LASSO and Elastic Net regression to enhance estimation accuracy. The proposed model has major components: preprocessing, train-test split, training with default parameters, and cross-validation. During the preprocessing phase, the entire dataset is normalized. After normalization, a train-test split is performed on the dataset, setting training at 80% and testing set to 20%. We chose two different phases for training the two algorithms (Elastic Net and LASSO) regression following the train-test-split. In the first phase, the two algorithms are trained using their default parameters and evaluated on the testing data. In the second phase, the grid search technique (the grid is used to search for tuning and select optimum parameters) and 5-fold cross-validation to get the final trained model. Finally, the final trained model is evaluated using the testing set. The experimental work is applied to the agile story point dataset of 21 software projects collected from six firms. The results show that both Elastic Net and LASSO regression outperformed the compared ones. Compared to the proposed algorithms, LASSO regression achieved better predictive performance and has acquired PRED (8%) and PRED (25%) results of 100.0, MMRE of 0.0491, MMER of 0.0551, MdMRE of 0.0593, MdMER of 0.063, and MSE of 0.0007. The result implies LASSO regression algorithm trained model is the most acceptable, and higher estimation performance exists in the literature.Keywords: agile software development, effort estimation, elastic net regression, LASSO
Procedia PDF Downloads 576493 Angiogenesis and Blood Flow: The Role of Blood Flow in Proliferation and Migration of Endothelial Cells
Authors: Hossein Bazmara, Kaamran Raahemifar, Mostafa Sefidgar, Madjid Soltani
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Angiogenesis is formation of new blood vessels from existing vessels. Due to flow of blood in vessels, during angiogenesis, blood flow plays an important role in regulating the angiogenesis process. Multiple mathematical models of angiogenesis have been proposed to simulate the formation of the complicated network of capillaries around a tumor. In this work, a multi-scale model of angiogenesis is developed to show the effect of blood flow on capillaries and network formation. This model spans multiple temporal and spatial scales, i.e. intracellular (molecular), cellular, and extracellular (tissue) scales. In intracellular or molecular scale, the signaling cascade of endothelial cells is obtained. Two main stages in development of a vessel are considered. In the first stage, single sprouts are extended toward the tumor. In this stage, the main regulator of endothelial cells behavior is the signals from extracellular matrix. After anastomosis and formation of closed loops, blood flow starts in the capillaries. In this stage, blood flow induced signals regulate endothelial cells behaviors. In cellular scale, growth and migration of endothelial cells is modeled with a discrete lattice Monte Carlo method called cellular Pott's model (CPM). In extracellular (tissue) scale, diffusion of tumor angiogenic factors in the extracellular matrix, formation of closed loops (anastomosis), and shear stress induced by blood flow is considered. The model is able to simulate the formation of a closed loop and its extension. The results are validated against experimental data. The results show that, without blood flow, the capillaries are not able to maintain their integrity.Keywords: angiogenesis, endothelial cells, multi-scale model, cellular Pott's model, signaling cascade
Procedia PDF Downloads 4166492 Microgrid: An Alternative of Electricity Supply to an Island in Thailand
Authors: Pawitchaya Srijaiwong, Surin Khomfoi
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There are several solutions to supply electricity to an island in Thailand such as diesel generation, submarine power cable, and renewable energy power generation. However, each alternative has its own limitation like fuel and pollution of diesel generation, submarine power cable length resulting in loss of cable and cost of investment, and potential of renewable energy in the local area. This paper shows microgrid system which is a new alternative for power supply to an island. It integrates local power plant from renewable energy, energy storage system, and microgrid controller. The suitable renewable energy power generation on an island is selected from geographic location and potential evaluation. Thus, photovoltaic system and hydro power plant are taken into account. The capacity of energy storage system is also estimated by transient stability study in order to supply electricity demand sufficiently under normal condition. Microgrid controller plays an important role in conducting, communicating and operating for both sources and loads on an island so that its functions are discussed in this study. The conceptual design of microgrid operation is investigated in order to analyze the reliability and power quality. The result of this study shows that microgrid is able to operate in parallel with the main grid and in case of islanding. It is applicable for electricity supply to an island and a remote area. The advantages of operating microgrid on an island include the technical aspect like improving reliability and quality of power system and social aspects like outage cost saving and CO₂ reduction.Keywords: energy storage, islanding, microgrid, renewable energy
Procedia PDF Downloads 3216491 Role of Radiologic Technologist Specialist in Plain Image Interpretation of Adults in the Middle East: A Radiologist’s Perspective
Authors: Awad Mohamed Elkhadir, Rajab M. Ben Yousef
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Background/Aim: Radiological technologists are medical professionals who perform diagnostic imaging tests such as X-rays, magnetic resonance imaging (MRI) scans, and computer tomography (CT) scans. Despite the recognition of image interpretation by British radiologists, it is still considered a problem in the Arab world. This study evaluates the perceptions of radiologists in the Middle East concerning the plain image interpretation of adults by radiologic technologist specialists. Methods: This is a cross-sectional study that follows a quantitative approach. A close-ended questionnaire was distributed among 103 participants who were radiologists by profession from various hospitals in Saudi Arabia and Sudan. The gathered data was then analyzed through Statistical Package for Social Sciences (SPSS). Results: The results showed that 29% recognized the Radiologic Technologist Specialist (RTS) role of writing image reports, while 61% did not. A total of 38% of participants believed that RTS image interpretation would help diagnose unreported radiographs. 47% of the sample responded that the workload and stress on radiologists would reduce by allowing reporting for RTS, while 37% did not. Lastly, 43% believe that image interpretation by RTS can be introduced into the Middle East in the future. Conclusion: The study's findings reveal that the combination of image reporting and radiography improves the care of the patients. The study's outcomes also show that the burden of the medical practitioners reduces due to image reporting of the radiographers. Further researches need to be conducted in the Arab World to obtain and measure the associated factors of the desired criteria.Keywords: Arab world, image interpretation, radiographer, radiologist, Saudi Arabia, Sudan
Procedia PDF Downloads 946490 Eco-Fashion Dyeing of Denim and Knitwear with Particle-Dyes
Authors: Adriana Duarte, Sandra Sampaio, Catia Ferreira, Jaime I. N. R. Gomes
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With the fashion of faded worn garments the textile industry has moved from indigo and pigments to dyes that are fixed by cationization, with products that can be toxic, and that can show this effect after washing down the dye with friction and/or treating with enzymes in a subsequent operation. Increasingly they are treated with bleaches, such as hypochlorite and permanganate, both toxic substances. An alternative process is presented in this work for both garment and jet dyeing processes, without the use of pre-cationization and the alternative use of “particle-dyes”. These are hybrid products, made up by an inorganic particle and an organic dye. With standard soluble dyes, it is not possible to avoid diffusion into the inside of the fiber unless using previous cationization. Only in this way can diffusion be avoided keeping the centre of the fibres undyed so as to produce the faded effect by removing the surface dye and showing the white fiber beneath. With “particle-dyes”, previous cationization is avoided. By applying low temperatures, the dye does not diffuse completely into the inside of the fiber, since it is a particle and not a soluble dye, being then able to give the faded effect. Even though bleaching can be used it can also be avoided, by the use of friction and enzymes they can be used just as for other dyes. This fashion brought about new ways of applying reactive dyes by the use of previous cationization of cotton, lowering the salt, and temperatures that reactive dyes usually need for reacting and as a side effect the application of a more environmental process. However, cationization is a process that can be problematic in applying it outside garment dyeing, such as jet dyeing, being difficult to obtain level dyeings. It also should be applied by a pad-fix or Pad-batch process due to the low affinity of the pre-cationization products making it a more expensive process, and the risk of unlevelness in processes such as jet dyeing. Wit particle-dyes, since no pre-cationizartion is necessary, they can be applied in jet dyeing. The excess dye is fixed by a fixing agent, fixing the insoluble dye onto the surface of the fibers. By applying the fixing agent only one to 1-3 rinses in water at room temperature are necessary, saving water and improving the washfastness.Keywords: denim, garment dyeing, worn look, eco-fashion
Procedia PDF Downloads 5326489 Associations Between Positive Body Image, Physical Activity and Dietary Habits in Young Adults
Authors: Samrah Saeed
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Introduction: This study considers a measure of positive body image and the associations between body appreciation, beauty ideals internalization, dietary habits, and physical activity in young adults. Positive body image is assessed by Body Appreciation Scale 2. It is used to assess a person's acceptance of the body, the degree of positivity, and respect for the body.Regular physical activity and healthy eating arebasically important for the body, and they play an important role in creating a positive image of the body. Objectives: To identify the associations between body appreciation and beauty ideals internalization. To compare body appreciation and body ideals internalization among students of different physical activity. To explore the associations between dietary habits (unhealthy, healthy), body appreciation and body ideals internalization. Research methods and organization: Study participants were young adult students, aged 18-35, both male and female.The research questionnaire consisted of four areas: body appreciation, beauty ideals internalization, dietary habits, and physical activity.The questionnaire was created in Google Forms online survey platform.The questionnaire was filled out anonymously Result and Discussion: Physical dissatisfaction, diet, eating disorders and exercise disorders are found in young adults all over the world.Thorough nutrition helps people understand who they are by reassuring them that they are okay without judging or accepting themselves. Social media can positively influence body image in many ways.A healthy body image is important because it affect self-esteem, self-acceptance, and your attitude towards food and exercise.Keywords: pysical activity, dietary habits, body image, beauty ideals internalization, body appreciation
Procedia PDF Downloads 896488 A Pilot Study Exploring Dog Owners’ Perceptions on Volunteering With Their Dogs in Animal-Assisted Therapy Program in Singapore
Authors: Julia Wong, Hua Beng Lim, Cheryl Ho, Gin Jen Gwee, Rachel Tay
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In Singapore, a few hospitals and non-governmental social service agencies have been utilising animal-assisted therapy (AAT) in their practice in recent years, although the animals used (e.g., dogs, cats, and horses) and program modality may differ due to the different practice settings, client profiles, and intervention goals. This pilot study explores dog owners’ perceptions of AAT with a focus on examining the enablers and barriers towards volunteering with their dogs in AAT programs in Singapore. A qualitative, thematic analysis study was conducted using in-depth, semi-structured interviews with 16 dog owners. 3 of the dog owners had previous experience volunteering with their dogs serving elderly patients in a community hospital, while the rest of the dog owners had no previous experience volunteering with their dogs. The former group was recruited with the help of the hospital, while the latter group was recruited via word-of-mouth. Dog owners who had volunteering experiences in AAT program versus those who had none differed in their perceptions towards AAT. Dog owners who had volunteered with their dogs in an AAT program in a hospital felt that their volunteering experience were meaningful to patients and to themselves, as they were intrinsically motivated by the desire to serve the community. Those who had not volunteered were hesitant to volunteer with their dogs as they were not comfortable with strangers touching their dogs. They also felt that it would be a huge commitment in terms of time and money; most of them do not own a car as it is uneconomical, and pets are not allowed on Singapore’s public transport systems. This study is limited by its small sample size, and its findings are not generalisable. However, given that volunteers are an invaluable resource in healthcare settings, future studies can examine more stakeholders’ perceptions towards AAT.Keywords: animal-assisted therapy, dog-assisted therapy, volunteers, complementary therapy
Procedia PDF Downloads 946487 Yields and Composition of the Gas, Liquid and Solid Fractions Obtained by Conventional Pyrolysis of Different Lignocellulosic Biomass Residues
Authors: María del Carmen Recio-Ruiz, Ramiro Ruiz-Rosas, Juana María Rosas, José Rodríguez-Mirasol, Tomás Cordero
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Nowadays, fossil resources are main precursors for fuel production. Due to their contribution to the greenhouse effect and their future depletion, there is a constant search for environmentally friendly feedstock alternatives. Biomass residues constitute an interesting replacement for fossil resources because of their zero net CO₂ emissions. One of the main routes to convert biomass into energy and chemicals is pyrolysis. In this work, conventional pyrolysis of different biomass residues highly available such as almond shells, hemp hurds, olive stones, and Kraft lignin, was studied. In a typical experiment, the biomass was crushed and loaded into a fixed bed reactor under continuous nitrogen flow. The influence of temperature (400-800 ºC) and heating rate (10 and 20 ºC/min) on the pyrolysis yield and composition of the different fractions has been studied. In every case, the mass yields revealed that the solid fraction decreased with temperature, while liquid and gas fractions increased due to depolymerization and cracking reactions at high temperatures. The composition of every pyrolysis fraction was studied in detail. The results showed that the composition of the gas fraction was mainly CO, CO₂ when working at low temperatures, and mostly CH₄ and H₂at high temperatures. The solid fraction developed an incipient microporosity, with narrow micropore volume of 0.21 cm³/g. Regarding the liquid fraction, pyrolysis of almond shell, hemp hurds, and olive stones led mainly to a high content in aliphatic acids and furans, due to the high volatile matter content of these biomass (>74 %wt.), and phenols to a lesser degree, which were formed due to the degradation of lignin at higher temperatures. However, when Kraft lignin was used as bio-oil precursor, the presence of phenols was very prominent, and aliphatic compounds were also detected in a lesser extent.Keywords: Bio-oil, biomass, conventional pyrolysis, lignocellulosic
Procedia PDF Downloads 1286486 Acclimation of in vitro-Propagated Apple Plantlets as Affected by Light Intensity
Authors: Guem-Jae Chung, Jin-Hui Lee, Myung-Min Oh
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Environmental control of in vitro-propagated apple plantlets is required for successful acclimation to ex vitro due to its low survival rate. This study aimed to determine the proper lighting condition for ex vitro acclimation of the apple plantlets in plant factories. In vitro-propagated M9 apple plantlets treated with pre-acclimatization for 1 week were exposed to following light treatments for additional 6 weeks; 60 μmol·m⁻²·s⁻¹ (A), 100 μmol·m⁻²·s⁻¹ (B), 140 μmol·m⁻²·s⁻¹ (C), 180 μmol·m⁻²·s⁻¹ (D), 60 μmol·m⁻²·s⁻¹ → 100 μmol·m⁻²·s⁻¹ at 2 weeks (E) or 4 weeks (F), 60 μmol·m⁻²·s⁻¹ → 100 μmol·m⁻²·s⁻¹ at 2 weeks → 140 μmol·m⁻²·s⁻¹ at 4 weeks (G) and 60 μmol·m⁻²·s⁻¹ → 140 μmol·m⁻²·s⁻¹ at 4 weeks (H). Shoot height, total leaf area, soil-plant analysis development (SPAD) value, root length, fresh and dry weights of shoots and roots were measured every 2 weeks after transplanting. In addition, the photosynthetic rate was measured at 5 weeks after transplanting. At 6 weeks after transplanting, shoot height of B was significantly higher than the other treatments. SPAD value, total leaf area and root length of B and F were relatively higher than the other treatments. Root fresh weights of B, D, F, and G were relatively higher than those in the other treatments. D induced the highest value in shoot fresh weight probably due to stem hardening, but it also resulted in shoot damage in the early stage of acclimation. Photosynthetic rate at 5 weeks after the transplanting was significantly increased as the light intensity increased. These results suggest that 100 μmol·m⁻²·s⁻¹ for 6 weeks (B) or gradually increased treatment from 60 μmol·m⁻²·s⁻¹ to 140 μmol·m⁻²·s⁻¹ at 2 weeks interval (F) were the proper lighting conditions for successful acclimation of in vitro-propagated apple plantlets. Acknowledgment: This work was supported by Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (IPET) through Agri-Bio industry Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA) (315003051SB020).Keywords: acclimation, in vitro-propagated apple plantlets, light intensity, plant factory
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