Search results for: size and content effects
982 Influence of Atmospheric Circulation Patterns on Dust Pollution Transport during the Harmattan Period over West Africa
Authors: Ayodeji Oluleye
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This study used Total Ozone Mapping Spectrometer (TOMS) Aerosol Index (AI) and reanalysis dataset of thirty years (1983-2012) to investigate the influence of the atmospheric circulation on dust transport during the Harmattan period over WestAfrica using TOMS data. The Harmattan dust mobilization and atmospheric circulation pattern were evaluated using a kernel density estimate which shows the areas where most points are concentrated between the variables. The evolution of the Inter-Tropical Discontinuity (ITD), Sea surface Temperature (SST) over the Gulf of Guinea, and the North Atlantic Oscillation (NAO) index during the Harmattan period (November-March) was also analyzed and graphs of the average ITD positions, SST and the NAO were observed on daily basis. The Pearson moment correlation analysis was also employed to assess the effect of atmospheric circulation on Harmattan dust transport. The results show that the departure (increased) of TOMS AI values from the long-term mean (1.64) occurred from around 21st of December, which signifies the rich dust days during winter period. Strong TOMS AI signal were observed from January to March with the maximum occurring in the latter months (February and March). The inter-annual variability of TOMSAI revealed that the rich dust years were found between 1984-1985, 1987-1988, 1997-1998, 1999-2000, and 2002-2004. Significantly, poor dust year was found between 2005 and 2006 in all the periods. The study has found strong north-easterly (NE) trade winds were over most of the Sahelianregion of West Africa during the winter months with the maximum wind speed reaching 8.61m/s inJanuary.The strength of NE winds determines the extent of dust transport to the coast of Gulf of Guinea during winter. This study has confirmed that the presence of the Harmattan is strongly dependent on theSST over Atlantic Ocean and ITD position. The locus of the average SST and ITD positions over West Africa could be described by polynomial functions. The study concludes that the evolution of near surface wind field at 925 hpa, and the variations of SST and ITD positions are the major large scale atmospheric circulation systems driving the emission, distribution, and transport of Harmattan dust aerosols over West Africa. However, the influence of NAO was shown to have fewer significance effects on the Harmattan dust transport over the region.Keywords: atmospheric circulation, dust aerosols, Harmattan, West Africa
Procedia PDF Downloads 315981 Risks of Investment in the Development of Its Personnel
Authors: Oksana Domkina
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According to the modern economic theory, human capital became one of the main production factors and the most promising direction of investment, as such investment provides opportunity of obtaining high and long-term economic and social effects. Informational technology (IT) sector is the representative of this new economy which is most dependent on human capital as the main competitive factor. So the question for this sector is not whether investment in development of personal should be made, but what are the most effective ways of executing it and who has to pay for the education: Worker, company or government. In this paper we examine the IT sector, describe the labor market of IT workers and its development, and analyze the risks that IT companies may face if they invest in the development of their workers and what factors influence it. The main problem and difficulty of quantitative estimation of risk of investment in human capital of a company and its forecasting is human factor. Human behavior is often unpredictable and complex, so it requires specific approaches and methods of assessment. To build a comprehensive method of estimation of the risk of investment in human capital of a company considering human factor, we decided to use the method of analytic hierarchy process (AHP), that initially was created and developed. We separated three main group of factors: Risks related to the worker, related to the company, and external factors. To receive data for our research, we conducted a survey among the HR departments of Ukrainian IT companies used them as experts for the AHP method. Received results showed that IT companies mostly invest in the development of their workers, although several hire only already qualified personnel. According to the results, the most significant risks are the risk of ineffective training and the risk of non-investment that are both related to the firm. The analysis of risk factors related to the employee showed that, the factors of personal reasons, motivation, and work performance have almost the same weights of importance. Regarding internal factors of the company, there is a high role of the factor of compensation and benefits, factors of interesting projects, team, and career opportunities. As for the external environment, one of the most dangerous factor of risk is competitor activities, meanwhile the political and economical situation factor also has a relatively high weight, which is easy to explain by the influence of severe crisis in Ukraine during 2014-2015. The presented method allows to take into consideration all main factors that affect the risk of investment in human capital of a company. This gives a base for further research in this field and allows for a creation of a practical framework for making decisions regarding the personnel development strategy and specific employees' development plans for the HR departments.Keywords: risks, personnel development, investment in development, factors of risk, risk of investment in development, IT, analytic hierarchy process, AHP
Procedia PDF Downloads 302980 Examination of the South African Fire Legislative Framework
Authors: Mokgadi Julia Ngoepe-Ntsoane
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The article aims to make a case for a legislative framework for the fire sector in South Africa. Robust legislative framework is essential for empowering those with obligatory mandate within the sector. This article contributes to the body of knowledge in the field of policy reviews particularly with regards to the legal framework. It has been observed overtime that the scholarly contributions in this field are limited. Document analysis was the methodology selected for the investigation of the various legal frameworks existing in the country. It has been established that indeed the national legislation on the fire industry does not exist in South Africa. From the documents analysed, it was revealed that the sector is dominated by cartels who are exploiting the new entrants to the market particularly SMEs. It is evident that these cartels are monopolising the system as they have long been operating in the system turning it into self- owned entities. Commitment to addressing the challenges faced by fire services and creating a framework for the evolving role that fire brigade services are expected to execute in building safer and sustainable communities is vital. Legislation for the fire sector ought to be concluded with immediate effect. The outdated national fire legislation has necessitated the monopolisation and manipulation of the system by dominating organisations which cause a painful discrimination and exploitation of smaller service providers to enter the market for trading in that occupation. The barrier to entry bears long term negative effects on national priority areas such as employment creation, poverty, and others. This monopolisation and marginalisation practices by cartels in the sector calls for urgent attention by government because if left attended, it will leave a lot of people particularly women and youth being disadvantaged and frustrated. The downcast syndrome exercised within the fire sector has wreaked havoc and is devastating. This is caused by cartels that have been within the sector for some time, who know the strengths and weaknesses of processes, shortcuts, advantages and consequences of various actions. These people take advantage of new entrants to the sector who in turn find it difficult to manoeuvre, find the market dissonant and end up giving up their good ideas and intentions. There are many pieces of legislation which are industry specific such as housing, forestry, agriculture, health, security, environmental which are used to regulate systems within the institutions involved. Other regulations exist as bi-laws for guiding the management within the municipalities.Keywords: sustainable job creation, growth and development, transformation, risk management
Procedia PDF Downloads 177979 Charcoal Traditional Production in Portugal: Contribution to the Quantification of Air Pollutant Emissions
Authors: Cátia Gonçalves, Teresa Nunes, Inês Pina, Ana Vicente, C. Alves, Felix Charvet, Daniel Neves, A. Matos
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The production of charcoal relies on rudimentary technologies using traditional brick kilns. Charcoal is produced under pyrolysis conditions: breaking down the chemical structure of biomass under high temperature in the absence of air. The amount of the pyrolysis products (charcoal, pyroligneous extract, and flue gas) depends on various parameters, including temperature, time, pressure, kiln design, and wood characteristics like the moisture content. This activity is recognized for its inefficiency and high pollution levels, but it is poorly characterized. This activity is widely distributed and is a vital economic activity in certain regions of Portugal, playing a relevant role in the management of woody residues. The location of the units establishes the biomass used for charcoal production. The Portalegre district, in the Alto Alentejo region (Portugal), is a good example, essentially with rural characteristics, with a predominant farming, agricultural, and forestry profile, and with a significant charcoal production activity. In this district, a recent inventory identifies almost 50 charcoal production units, equivalent to more than 450 kilns, of which 80% appear to be in operation. A field campaign was designed with the objective of determining the composition of the emissions released during a charcoal production cycle. A total of 30 samples of particulate matter and 20 gas samples in Tedlar bags were collected. Particulate and gas samplings were performed in parallel, 2 in the morning and 2 in the afternoon, alternating the inlet heads (PM₁₀ and PM₂.₅), in the particulate sampler. The gas and particulate samples were collected in the plume as close as the emission chimney point. The biomass (dry basis) used in the carbonization process was a mixture of cork oak (77 wt.%), holm oak (7 wt.%), stumps (11 wt.%), and charred wood (5 wt.%) from previous carbonization processes. A cylindrical batch kiln (80 m³) with 4.5 m diameter and 5 m of height was used in this study. The composition of the gases was determined by gas chromatography, while the particulate samples (PM₁₀, PM₂.₅) were subjected to different analytical techniques (thermo-optical transmission technique, ion chromatography, HPAE-PAD, and GC-MS after solvent extraction) after prior gravimetric determination, to study their organic and inorganic constituents. The charcoal production cycle presents widely varying operating conditions, which will be reflected in the composition of gases and particles produced and emitted throughout the process. The concentration of PM₁₀ and PM₂.₅ in the plume was calculated, ranging between 0.003 and 0.293 g m⁻³, and 0.004 and 0.292 g m⁻³, respectively. Total carbon, inorganic ions, and sugars account, in average, for PM10 and PM₂.₅, 65 % and 56 %, 2.8 % and 2.3 %, 1.27 %, and 1.21 %, respectively. The organic fraction studied until now includes more than 30 aliphatic compounds and 20 PAHs. The emission factors of particulate matter to produce charcoal in the traditional kiln were 33 g/kg (wooddb) and 27 g/kg (wooddb) for PM₁₀ and PM₂.₅, respectively. With the data obtained in this study, it is possible to fill the lack of information about the environmental impact of the traditional charcoal production in Portugal. Acknowledgment: Authors thanks to FCT – Portuguese Science Foundation, I.P. and to Ministry of Science, Technology and Higher Education of Portugal for financial support within the scope of the project CHARCLEAN (PCIF/GVB/0179/2017) and CESAM (UIDP/50017/2020 + UIDB/50017/2020).Keywords: brick kilns, charcoal, emission factors, PAHs, total carbon
Procedia PDF Downloads 149978 Characterization of Polymorphic Forms of Rifaximin
Authors: Ana Carolina Kogawa, Selma Gutierrez Antonio, Hérida Regina Nunes Salgado
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Rifaximin is an oral antimicrobial, gut - selective and not systemic with adverse effects compared to placebo. It is used for the treatment of hepatic encephalopathy, travelers diarrhea, irritable bowel syndrome, Clostridium difficile, ulcerative colitis and acute diarrhea. The crystalline form present in the rifaximin with minimal systemic absorption is α, being the amorphous form significantly different. Regulators are increasingly attention to polymorphisms. Polymorphs can change the form by altering the drug characteristics compromising the effectiveness and safety of the finished product. International Conference on Harmonization issued the ICH Guidance Q6A, which aim to improve the control of polymorphism in new and existing pharmaceuticals. The objective of this study was to obtain polymorphic forms of rifaximin employing recrystallization processes and characterize them by thermal analysis (thermogravimetry - TG and differential scanning calorimetry - DSC), X-ray diffraction, scanning electron microscopy and solubility test. Six polymorphic forms of rifaximin, designated I to VI were obtained by the crystallization process by evaporation of the solvent. The profiles of the TG curves obtained from polymorphic forms of rifaximin are similar to rifaximin and each other, however, the DTG are different, indicating different thermal behaviors. Melting temperature values of all the polymorphic forms were greater to that shown by the rifaximin, indicating the higher thermal stability of the obtained forms. The comparison of the diffractograms of the polymorphic forms of rifaximin with rifaximin α, β and γ constant in patent indicate that forms III, V and VI are formed by mixing polymorph β and α and form III is formed by polymorph β. The polymorphic form I is formed by polymorph β, but with a significant amount of amorphous material. Already, the polymorphic form II consists of polymorph γ, amorphous. In scanning electron microscope is possible to observe the heterogeneity of morphological characteristics of crystals of polymorphic forms among themselves and with rifaximin. The solubility of forms I and II was greater than the solubility of rifaximin, already, forms III, IV and V presented lower solubility than of rifaximin. Similarly, the bioavailability of the amorphous form of rifaximin is considered significantly higher than the form α, the polymorphic forms obtained in this work can not guarantee the excellent tolerability of the reference medicine. Therefore, studies like these are extremely important and they point to the need for greater requirements by the regulatory agencies competent about polymorphs analysis of the raw materials used in the manufacture of medicines marketed globally. These analyzes are not required in the majority of official compendia. Partnerships between industries, research centers and universities would be a viable way to consolidate researches in this area and contribute to improving the quality of solid drugs.Keywords: electronic microscopy, polymorphism, rifaximin, solubility, X-ray diffraction
Procedia PDF Downloads 672977 Screening and Improved Production of an Extracellular β-Fructofuranosidase from Bacillus Sp
Authors: Lynette Lincoln, Sunil S. More
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With the rising demand of sugar used today, it is proposed that world sugar is expected to escalate up to 203 million tonnes by 2021. Hydrolysis of sucrose (table sugar) into glucose and fructose equimolar mixture is catalyzed by β-D-fructofuranoside fructohydrolase (EC 3.2.1.26), commonly called as invertase. For fluid filled center in chocolates, preparation of artificial honey, as a sweetener and especially to ensure that food stuffs remain fresh, moist and soft for longer spans invertase is applied widely and is extensively being used. From an industrial perspective, properties such as increased solubility, osmotic pressure and prevention of crystallization of sugar in food products are highly desired. Screening for invertase does not involve plate assay/qualitative test to determine the enzyme production. In this study, we use a three-step screening strategy for identification of a novel bacterial isolate from soil which is positive for invertase production. The primary step was serial dilution of soil collected from sugarcane fields (black soil, Maddur region of Mandya district, Karnataka, India) was grown on a Czapek-Dox medium (pH 5.0) containing sucrose as the sole C-source. Only colonies with the capability to utilize/breakdown sucrose exhibited growth. Bacterial isolates released invertase in order to take up sucrose, splitting the disaccharide into simple sugars. Secondly, invertase activity was determined from cell free extract by measuring the glucose released in the medium at 540 nm. Morphological observation of the most potent bacteria was examined by several identification tests using Bergey’s manual, which enabled us to know the genus of the isolate to be Bacillus. Furthermore, this potent bacterial colony was subjected to 16S rDNA PCR amplification and a single discrete PCR amplicon band of 1500 bp was observed. The 16S rDNA sequence was used to carry out BLAST alignment search tool of NCBI Genbank database to obtain maximum identity score of sequence. Molecular sequencing and identification was performed by Xcelris Labs Ltd. (Ahmedabad, India). The colony was identified as Bacillus sp. BAB-3434, indicating to be the first novel strain for extracellular invertase production. Molasses, a by-product of the sugarcane industry is a dark viscous liquid obtained upon crystallization of sugar. An enhanced invertase production and optimization studies were carried out by one-factor-at-a-time approach. Crucial parameters such as time course (24 h), pH (6.0), temperature (45 °C), inoculum size (2% v/v), N-source (yeast extract, 0.2% w/v) and C-source (molasses, 4% v/v) were found to be optimum demonstrating an increased yield. The findings of this study reveal a simple screening method of an extracellular invertase from a rapidly growing Bacillus sp., and selection of best factors that elevate enzyme activity especially utilization of molasses which served as an ideal substrate and also as C-source, results in a cost-effective production under submerged conditions. The invert mixture could be a replacement for table sugar which is an economic advantage and reduce the tedious work of sugar growers. On-going studies involve purification of extracellular invertase and determination of transfructosylating activity as at high concentration of sucrose, invertase produces fructooligosaccharides (FOS) which possesses probiotic properties.Keywords: Bacillus sp., invertase, molasses, screening, submerged fermentation
Procedia PDF Downloads 235976 Fatty Acid Translocase (Cd36), Energy Substrate Utilization, and Insulin Signaling in Brown Adipose Tissue in Spontaneously Hypertensive Rats
Authors: Michal Pravenec, Miroslava Simakova, Jan Silhavy
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Brown adipose tissue (BAT) plays an important role in lipid and glucose metabolism in rodents and possibly also in humans. Recently, using systems genetics approach in the BAT from BXH/HXB recombinant inbred strains, derived from the SHR (spontaneously hypertensive rat) and BN (Brown Norway) progenitors, we identified Cd36 (fatty acid translocase) as the hub gene of co-expression module associated with BAT relative weight and function. An important aspect of BAT biology is to better understand the mechanisms regulating the uptake and utilization of fatty acids and glucose. Accordingly, BAT function in the SHR that harbors mutant nonfunctional Cd36 variant (hereafter referred to as SHR-Cd36⁻/⁻) was compared with SHR transgenic line expressing wild type Cd36 under control of a universal promoter (hereafter referred to as SHR-Cd36⁺/⁺). BAT was incubated in media containing insulin and 14C-U-glucose alone or 14C-U-glucose together with palmitate. Incorporation of glucose into BAT lipids was significantly higher in SHR-Cd36⁺/⁺ versus SHR-Cd36⁻/⁻ rats when incubation media contained glucose alone (SHR-Cd36⁻/⁻ 591 ± 75 vs. SHR-Cd36⁺/⁺ 1036 ± 135 nmol/gl./2h; P < 0.005). Adding palmitate into incubation media had no effect in SHR-Cd36⁻/⁻ rats but significantly reduced glucose incorporation into BAT lipids in SHR-Cd36⁺/⁺ (SHR-Cd36⁻/⁻ 543 ± 55 vs. SHR-Cd36⁺/⁺ 766 ± 75 nmol/gl./2h; P < 0.05 denotes significant Cd36 x palmitate interaction determined by two-way ANOVA). This Cd36-dependent reduced glucose uptake in SHR-Cd36⁺/⁺ BAT was likely secondary to increased palmitate incorporation and utilization due to the presence of wild type Cd36 fatty acid translocase in transgenic rats. This possibility is supported by increased incorporation of 14C-U-palmitate into BAT lipids in the presence of both palmitate and glucose in incubation media (palmitate alone: SHR-Cd36⁻/⁻ 870 ± 21 vs. SHR-Cd36⁺/⁺ 899 ± 42; glucose+palmitate: SHR-Cd36⁻/⁻ 899 ± 47 vs. SHR-Cd36⁺/⁺ 1460 ± 111 nmol/palm./2h; P < 0.05 denotes significant Cd36 x glucose interaction determined by two-way ANOVA). It is possible that addition of glucose into the incubation media increased palmitate incorporation into BAT lipids in SHR-Cd36⁺/⁺ rats because of glucose availability for glycerol phosphate production and increased triglyceride synthesis. These changes in glucose and palmitate incorporation into BAT lipids were associated with significant differential expression of Irs1, Irs2, Slc2a4 and Foxo1 genes involved in insulin signaling and glucose metabolism only in SHR-Cd36⁺/⁺ rats which suggests Cd36-dependent effects on insulin action. In conclusion, these results provide compelling evidence that Cd36 plays an important role in BAT insulin signaling and energy substrate utilization.Keywords: brown adipose tissue, Cd36, energy substrate utilization, insulin signaling, spontaneously hypertensive rat
Procedia PDF Downloads 142975 Testing a Motivational Model of Physical Education on Contextual Outcomes and Total Moderate to Vigorous Physical Activity of Middle School Students
Authors: Arto Grasten
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Given the rising trend in obesity in children and youth, age-related decline in moderate- to- vigorous-intensity physical activity (MVPA) in several Western, African, and Asian countries in addition to limited evidence of behavioral, affective, cognitive outcomes in physical education, it is important to clarify the motivational processes in physical education classes behind total MVPA engagement. The present study examined the full sequence of the Hierarchical Model of Motivation in physical education including motivational climate, basic psychological needs, intrinsic motivation, contextual behavior, affect, cognition, total MVPA, and associated links to body mass index (BMI) and gender differences. A cross-sectional data comprised self-reports and objective assessments of 770 middle school students (Mage = 13.99 ± .81 years, 52% of girls) in North-East Finland. In order to test the associations between motivational climate, psychological needs, intrinsic motivation, cognition, behavior, affect, and total MVPA, a path model was implemented. Indirect effects between motivational climate and cognition, behavior, affect and total MVPA were tested by setting basic needs and intrinsic motivation as mediators into the model. The findings showed that direct and indirect paths for girls and boys associated with different contextual outcomes and girls’ indirect paths were not related with total MVPA. Precisely, task-involving climate-mediated by physical competence and intrinsic motivation related to enjoyment, importance, and graded assessments within girls, whereas task-involving climate associated with enjoyment and importance via competence and autonomy, and total MVPA via autonomy, intrinsic motivation, and importance within boys. Physical education assessments appeared to be essential in motivating students to participate in greater total MVPA. BMI was negatively linked with competence and relatedness only among girls. Although, the current and previous empirical findings supported task-involving teaching methods in physical education, in some cases, ego-involving climate should not be totally avoided. This may indicate that girls and boys perceive physical education classes in a different way. Therefore, both task- and ego-involving teaching practices can be useful ways of driving behavior in physical education classes.Keywords: achievement goal theory, assessment, enjoyment, hierarchical model of motivation, physical activity, self-determination theory
Procedia PDF Downloads 282974 Factors Relating to Motivation to Change Behaviors in Individuals Who Are Overweight
Authors: Teresa Wills, Geraldine Mccarthy, Nicola Cornally
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Background: Obesity is an emerging healthcare epidemic affecting virtually all age and socio-economic groups and is one of the most serious and prevalent diseases of the 21st century. It is a public health challenge because of its prevalence, associated costs and health effects. The increasing prevalence of obesity has created a social perception that overweight body sizes are healthy and normal. This normalization of obesity within our society and the acceptance of higher body weights have led to individuals being unaware of the reality of their weight status and gravity of this situation thus impeding recognition of obesity. Given the escalating global health problem of obesity and its co-morbidities, the need to re-appraise its management is more compelling than ever. It is widely accepted that the causes of obesity are complex and multi-factorial. Engagement of individuals in weight management programmes is difficult if they do not perceive they have a problem with their weight. Recognition of the problem is a key component of obesity management and identifying the main predictors of behaviour is key to designing health behaviour interventions. Aim: The aim of the research was to determine factors relating to motivation to change behaviours in individuals who perceive themselves to be overweight. Method: The research design was quantitative, correlational and cross-sectional. The design was guided by the Health Belief Model. Data were collected online using a multi-section and multi-item questionnaire, developed from a review of the theoretical and empirical research. A sample of 202 men and women who perceived themselves to be overweight participated in the research. Descriptive and inferential statistical analyses were employed to describe relationships between variables. Findings: Following multivariate regression analysis, perceived barriers to weight loss and perceived benefits of weight loss were significant predictors of motivation to change behaviour. The perceived barriers to weight loss which were significant were psychological barriers to weight loss (p = < 0.019) and environmental barriers to physical activity (p= < 0.032).The greatest predictor of motivation to change behaviour was the perceived benefits of weight loss (p < 0.001). Perceived susceptibility to obesity and perceived severity of obesity did not emerge as significant predictors in this model. Total variance explained by the model was 33.5%. Conclusion: Perceived barriers to weight loss and perceived benefits of weight loss are important determinants of motivation to change behaviour. These findings have important implications for health professionals to help inform their practice and for the development of intervention programmes to prevent and control obesity.Keywords: motivation to change behaviours, obesity, predictors of behavior, interventions, overweight
Procedia PDF Downloads 417973 Silk Fibroin-PVP-Nanoparticles-Based Barrier Membranes for Tissue Regeneration
Authors: Ivone R. Oliveira, Isabela S. Gonçalves, Tiago M. B. Campos, Leandro J. Raniero, Luana M. R. Vasconcellos, João H. Lopes
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Originally, the principles of guided tissue/bone regeneration (GTR/GBR) were followed to restore the architecture and functionality of the periodontal system. In essence, a biocompatible polymer-based occlusive membrane is used as a barrier to prevent migration of epithelial and connective tissue to the regenerating site. In this way, progenitor cells located in the remaining periodontal ligament can recolonize the root area and differentiate into new periodontal tissues, alveolar bone, and new connective attachment. The use of synthetic or collagen-derived membranes with or without calcium phosphate-based bone graft materials has been the treatment used. Ideally, these membranes need to exhibit sufficient initial mechanical strength to allow handling and implantation, withstand the various mechanical stresses suffered during surgery while maintaining their integrity, and support the process of bone tissue regeneration and repair by resisting cellular traction forces and wound contraction forces during tissue healing in vivo. Although different RTG/ROG products are available on the market, they have serious deficiencies in terms of mechanical strength. Aiming to improve the mechanical strength and osteogenic properties of the membrane, this work evaluated the production of membranes that integrate the biocompatibility of the natural polymer (silk fibroin - FS) and the synthetic polymer poly(vinyl pyrrolidone - PVP) with graphene nanoplates (NPG) and gold nanoparticles (AuNPs), using the electrospinning equipment (AeroSpinner L1.0 from Areka) which allows the execution of high voltage spinning and/or solution blowing and with a high production rate, enabling development on an industrial scale. Silk fibroin uniquely solved many of the problems presented by collagen and was used in this work because it has unique combined merits, such as programmable biodegradability, biocompatibility and sustainable large-scale production. Graphene has attracted considerable attention in recent years as a potential biomaterial for mechanical reinforcement because of its unique physicochemical properties and was added to improve the mechanical properties of the membranes associated or not with the presence of AuNPs, which have shown great potential in regulating osteoblast activity. The preparation of FS from silkworm cocoons involved cleaning, degumming, dissolution in lithium bromide, dialysis, lyophilization and dissolution in hexafluoroisopropanol (HFIP) to prepare the solution for electrospinning, and crosslinking tests were performed in methanol. The NPGs were characterized and underwent treatment in nitric acid for functionalization to improve the adhesion of the nanoplates to the PVP fibers. PVP-NPG membranes were produced with 0.5, 1.0 and 1.5 wt% functionalized or not and evaluated by SEM/FEG, FTIR, mechanical strength and cell culture assays. Functionalized GNP particles showed stronger binding, remaining adhered to the fibers. Increasing the graphene content resulted in higher mechanical strength of the membrane and greater biocompatibility. The production of FS-PVP-NPG-AuNPs hybrid membranes was performed by electrospinning in separate syringes and simultaneously the FS solution and the solution containing PVP-NPG 1.5 wt% in the presence or absence of AuNPs. After cross-linking, they were characterized by SEM/FEG, FTIR and behavior in cell culture. The presence of NPG-AuNPs increased the viability and the presence of mineralization nodules.Keywords: barrier membranes, silk fibroin, nanoparticles, tissue regeneration.
Procedia PDF Downloads 19972 Exploring the Influence of Normative, Financial and Environmental Decision Frames in Nudging 'Green' Behaviour, and Increasing Uptake of Energy-Efficient Technologies
Authors: Rebecca Hafner, Daniel Read, David Elmes
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The persuasive potential of normative and feedback (financial vs. environmental) information in ‘nudging’ people towards making environmentally sound decisions was explored in a hypothetical choice experiment. The research was specifically focused on determining how subtle variations in the decision frame could be used to increase the selection of energy efficient vs. standard technologies, using the context of home heating choice. Participants were given a choice of a standard heating system (a gas boiler) and a relatively more-energy efficient option (a heat pump). The experiment had a 2 (normative vs. no normative information) by 3 feedback type (financial, environmental, none) design. The last group constituted the control. Half of the participants were given normative information about what the majority of others in their neighbourhood had opted to do when faced with the same choice set, prior to making their decision. The other half received no such information. Varying feedback frames were incorporated by providing participants with information on either financial or environmental savings that could be achieved by choosing the heat pump. No such information was provided in the control group. A significant interaction was found between normative information and feedback frame type. Specifically, the impact of feedback frames was found to be reduced when normative information was provided; illustrating the overriding influence of normative information on option preference. Participants were significantly more likely to select the heat pump if they were vs. were not given normative information. Yet when no normative information was provided, the persuasive influence of the financial frame was increased – highlighting this as an effective means of encouraging uptake of new technologies in this instance. Conversely, the environmental frame was not found to differ significantly from the control. Marginal carryover effects were also found for stated future real-life decision-making behaviour, with participants who were versus were not given normative information being marginally more likely to state they would consider installing a heat pump when they next need to replace their heating system in real life. We conclude that normative and financial feedback framing techniques are highly effective in increasing uptake of new, energy efficient heating technologies involving significant upfront financial outlay. The implications for researchers looking to promote ‘green’ choice in the context of new technology adoption are discussed.Keywords: energy-efficient technology adoption, environmental decision making, financial vs. environmental feedback framing techniques, social norms
Procedia PDF Downloads 310971 Phytochemical Composition and Biological Activities of the Vegetal Extracts of Six Aromatic and Medicinal Plants of Algerian Flora and Their Uses in Food and Pharmaceutical Industries
Authors: Ziani Borhane Eddine Cherif, Hazzi Mohamed, Mouhouche Fazia
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The vegetal extracts of aromatic and medicinal plants start to have much of interest like potential sources of natural bioactive molecules. Many features are conferred by the nature of the chemical function of their major constituents (phenol, alcohol, aldehyde, cetone). This biopotential lets us to focalize on the study of three main biological activities, the antioxidant, antibiotic and insecticidal activities of six Algerian aromatic plants in the aim of making in evidence by the chromatographic analysis (CPG and CG/SM) the phytochemical compounds implicating in this effects. The contents of Oxygenated monoterpenes represented the most prominent group of constituents in the majority of plants. However, the α-Terpineol (28,3%), Carvacrol (47,3%), pulégone (39,5%), Chrysanthenone (27,4%), Thymol 23,9%, γ-Terpinene 23,9% and 2-Undecanone(94%) were the main components. The antioxyding activity of the Essential oils and no-volatils extracts was evaluated in vitro using four tests: inhibition of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the 2,2-Azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) radical-scavenging activity (ABTS•+), the thiobarbituric acid reactive substances (TBARS) assays and the reducing power. The measures of the IC50 of these natural compounds revealed potent activity (between 254.64-462.76mg.l-1), almost similar to that of BHT, BHA, Tocopherol and Ascorbic acid (126,4-369,1 mg.l-1) and so far than the Trolox one (IC50= 2,82mg.l-1). Furthermore, three ethanol extracts were found to be remarkably effective toward DPPH and ABTS inhibition, compared to chemical antioxidant BHA and BHT (IC = 9.8±0.1 and 28±0.7 mg.l-1, respectively); for reducing power test it has also exhibited high activity. The study on the insecticidal activity effect by contact, inhalation, fecundity and fertility of Callosobruchus maculatus and Tribolium confusum showed a strong potential biocide reaching 95-100% mortality only after 24 hours. The antibiotic activity of our essential oils were evaluated by a qualitative study (aromatogramme) and quantitative (MIC, MBC and CML) on four bacteria (Gram+ and Gram-) and one strain of pathogenic yeast, the results of these tests showed very interesting action than that induced by the same reference antibiotics (Gentamycin, and Nystatin Ceftatidine) such that the inhibition diameters and MIC values for tested microorganisms were in the range of 23–58 mm and 0.015–0.25%(v/v) respectively.Keywords: aromatic plants, essential oils, no-volatils extracts, bioactive molecules, antioxidant activity, insecticidal activity, antibiotic activity
Procedia PDF Downloads 222970 The Impact of Hosting an On-Site Vocal Concert in Preschool on Music Inspiration and Learning Among Preschoolers
Authors: Meiying Liao, Poya Huang
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The aesthetic domain is one of the six major domains in the Taiwanese preschool curriculum, encompassing visual arts, music, and dramatic play. Its primary objective is to cultivate children’s abilities in exploration and awareness, expression and creation, and response and appreciation. The purpose of this study was to explore the effects of hosting a vocal music concert on aesthetic inspiration and learning among preschoolers in a preschool setting. The primary research method employed was a case study focusing on a private preschool in Northern Taiwan that organized a school-wide event featuring two vocalists. The concert repertoires included children’s songs, folk songs, and arias performed in Mandarin, Hakka, English, German, and Italian. In addition to professional performances, preschool teachers actively participated by presenting a children’s song. A total of 5 classes, comprising approximately 150 preschoolers, along with 16 teachers and staff, participated in the event. Data collection methods included observation, interviews, and documents. Results indicated that both teachers and children thoroughly enjoyed the concert, with high levels of acceptance when the program was appropriately designed and hosted. Teachers reported that post-concert discussions with children revealed the latter’s ability to recall people, events, and elements observed during the performance, expressing their impressions of the most memorable segments. The concert effectively achieved the goals of the aesthetic domain, particularly in fostering response and appreciation. It also inspired preschoolers’ interest in music. Many teachers noted an increased desire for performance among preschoolers after exposure to the concert, with children imitating the performers and their expressions. Remarkably, one class extended this experience by incorporating it into the curriculum, autonomously organizing a high-quality concert in the music learning center. Parents also reported that preschoolers enthusiastically shared their concert experiences at home. In conclusion, despite being a single event, the positive responses from preschoolers towards the music performance suggest a meaningful impact. These experiences extended into the curriculum, as firsthand exposure to performances allowed teachers to deepen related topics, fostering a habit of autonomous learning in the designated learning centers.Keywords: concert, early childhood music education, aesthetic education, music develpment
Procedia PDF Downloads 51969 Collaboration with Governmental Stakeholders in Positioning Reputation on Value
Authors: Zeynep Genel
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The concept of reputation in corporate development comes to the fore as one of the most frequently discussed topics in recent years. Many organizations, which make worldwide investments, make effort in order to adapt themselves to the topics within the scope of this concept and to promote the name of the organization through the values that might become prominent. The stakeholder groups are considered as the most important actors determining the reputation. Even, the effect of stakeholders is not evaluated as a direct factor; it is signed as indirect effects of their perception are a very strong on ultimate reputation. It is foreseen that the parallelism between the projected reputation and the perceived c reputation, which is established as a result of communication experiences perceived by the stakeholders, has an important effect on achieving these objectives. In assessing the efficiency of these efforts, the opinions of stakeholders are widely utilized. In other words, the projected reputation, in which the positive and/or negative reflections of corporate communication play effective role, is measured through how the stakeholders perceptively position the organization. From this perspective, it is thought that the interaction and cooperation of corporate communication professionals with different stakeholder groups during the reputation positioning efforts play significant role in achieving the targeted reputation or in sustainability of this value. The governmental stakeholders having intense communication with mass stakeholder groups are within the most effective stakeholder groups of organization. The most important reason of this is that the organizations, regarding which the governmental stakeholders have positive perception, inspire more confidence to the mass stakeholders. At this point, the organizations carrying out joint projects with governmental stakeholders in parallel with sustainable communication approach come to the fore as the organizations having strong reputation, whereas the reputation of organizations, which fall behind in this regard or which cannot establish the efficiency from this aspect, is thought to be perceived as weak. Similarly, the social responsibility campaigns, in which the governmental stakeholders are involved and which play efficient role in strengthening the reputation, are thought to draw more attention. From this perspective, the role and effect of governmental stakeholders on the reputation positioning is discussed in this study. In parallel with this objective, it is aimed to reveal perspectives of seven governmental stakeholders towards the cooperation in reputation positioning. The sample group representing the governmental stakeholders is examined under the lights of results obtained from in-depth interviews with the executives of different ministries. It is asserted that this study, which aims to express the importance of stakeholder participation in corporate reputation positioning especially in Turkey and the effective role of governmental stakeholders in strong reputation, might provide a new perspective on measuring the corporate reputation, as well as establishing an important source to contribute to the studies in both academic and practical domains.Keywords: collaborative communications, reputation management, stakeholder engagement, ultimate reputation
Procedia PDF Downloads 229968 Optimizing the Residential Design Process Using Automated Technologies
Authors: Milena Nanova, Martin Georgiev, Damyan Damov
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Modern residential architecture is increasingly influenced by rapid urbanization, technological advancements, and growing investor expectations. The integration of AI and digital tools such as CAD and BIM (Building Information Modelling) is transforming the design process by improving efficiency, accuracy, and speed. However, urban development faces challenges, including the high competition for viable sites and the time-consuming nature of traditional investment feasibility studies and architectural planning. Finding and analyzing suitable sites for residential development is complicated by intense competition and rising investor demands. Investors require quick assessments of property potential to avoid missing opportunities, while traditional architectural design processes rely on the experience of the team and can be time-consuming, adding pressure to make fast, effective decisions. The widespread use of CAD tools has sped up the drafting process, enhancing both accuracy and efficiency. Digital tools allow designers to manipulate drawings quickly, reducing the time spent on revisions. BIM further advances this by enabling native 3D modelling, where changes to a design in one view are automatically reflected in all others, minimizing errors and saving time. AI is becoming an integral part of architectural design software. While AI is currently being incorporated into existing programs like AutoCAD, Revit, and ArchiCAD, its full potential is reached in parametric modelling. In this process, designers define parameters (e.g., building size, layout, and materials), and the software generates multiple design variations based on those inputs. This method accelerates the design process by automating decisions and enabling the quick generation of alternative solutions. The study utilizes generative design, a specific application of parametric modelling that uses Machine Learning (ML) to explore a wide range of design possibilities based on predefined criteria. It optimizes designs through iterations, testing many variations to find the best solutions. This process is particularly beneficial in the early stages of design, where multiple options are explored before refining the best ones. ML’s ability to handle complex mathematical tasks allows it to generate unconventional yet effective designs that a human designer might overlook. Residential architecture, with its anticipated and typical layouts and modular nature, is especially suitable for generative design. The relationships between rooms and the overall organization of apartment units follow logical patterns, making it an ideal candidate for parametric modelling. Using these tools, architects can quickly explore various apartment configurations, considering factors like apartment sizes, types, and circulation patterns, and identify the most efficient layout for a given site. Parametric modelling and generative design offer significant benefits to residential architecture by streamlining the design process, enabling faster decision-making, and optimizing building layouts. These technologies allow architects and developers to analyze numerous design possibilities, improving outcomes while responding to the challenges of urban development. By integrating ML-driven generative design, the architecture industry can enhance creativity, efficiency, and adaptability in residential projects.Keywords: architectural design, generative design, parametric models, residential buildings, workflow optimization
Procedia PDF Downloads 14967 Enforceability of the Right to Education and Rights in Education for Refugees after the European Refugee Crisis
Authors: Kurt Willems
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The right to education is a fundamental human right, which has been entrenched in many international and regional treaties and national constitutions. Nevertheless, practice shows that many obstacles impede easy access to quality education for refugees. Overall, the material effects of international human rights legislation on improving (irregular) migrants’ access to social rights in the European countries have remained limited due to the lack of guarantees on effective incorporation in the municipal legal order and due to the lack of effective enforcement mechanisms. After the recent refugee crisis in Europe, this issue has grown in importance. The presentation aims to give a brief overview of the most important issues impeding the effective enforceability of the right to education for refugees. I. Do refugees fall within the scope of application of the relevant human rights treaties and to which extent can they invoke human rights treaties in domestic courts to set aside domestic legislation? II. How is the justiciability of the right to education organized in those treaties? III. What is the legal answer to questions raised in practice when dealing with the influx of refugees in Europe: (i) can refugees be placed in separate schools or classes until they can follow the regular curriculum?; (ii) can higher school fees be asked from pupils without legal documents?; (iii) do refugees have a right to be taught in their own native language until they learn to speak the national language? To answer the above questions, the doctrinal and comparative legal method will be used. The normative framework, as interpreted within Europe, will be distilled from the recent and relevant international treaties and European law instruments (in particular the Convention on the Rights of the Child, the European Convention on human rights, the European Social Charter and the International Covenant on Economic, Social and Cultural Rights) and their underlying policy documents, the legal literature, the (limited) European jurisprudence, and the general comments to those treaties. The article is mainly descriptive in nature. Its aim is to serve as a summary of the legal provisions, case law and legal literature on the topic of the right to education for refugees. The research shows that the reasons for the delicate enforceability of the rights to and the rights in education are multifold. The research will categorize the different contributing factors under the following headings: (i) problems related to the justiciability of international law as such; (ii) problems specifically related to the educational field; (iii) problems related to policy issues in the refugee debate. By categorizing the reasons contributing to the difficult enforceability of the right to education and the rights in education for refugees, this research hopes to facilitate the search for solutions to this delicate problem.Keywords: right to education, refugees, discrimination, enforceability of human rights
Procedia PDF Downloads 243966 Oncology and Phytomedicine in the Advancement of Cancer Therapy for Better Patient Care
Authors: Hailemeleak Regassa
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Traditional medicines use medicinal plants as a source of ingredients, and many modern medications are indirectly derived from plants. Consumers in affluent nations are growing disenchanted with contemporary healthcare and looking for alternatives. Oxidative stress is the primary cause of multiple diseases, and exogenous antioxidant supplementation or strengthening the body's endogenous antioxidant defenses are potential ways to counteract the negative effects of oxidative damage. Plants can biosynthesize non-enzymatic antioxidants that can reduce ROS-induced oxidative damage. Aging often aids the propagation and development of carcinogenesis, and older animals and older people exhibit increased vulnerability to tumor promoters. Cancer is a major public health issue, with several anti-cancer medications in clinical use. Potential drugs such as flavopiridol, roscovitine, combretastatin A-4, betulinic acid, and silvestrol are in the clinical or preclinical stages of research. Methodology: Microbial Growth media, Dimethyl sulfoxide (DMSO), methanol, ethyl acetate, and n-hexane were obtained from Himedia Labs, Mumbai, India. plant were collected from the Herbal Garden of Shoolini University campus, Solan, India (Latitude - 30.8644° N and longitude - 77.1184° E). The identity was confirmed by Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni, Solan (H.P.), India, and documented in Voucher specimens - UHF- Herbarium no. 13784; vide book no. 3818 Receipt No. 086. The plant materials were washed with tap water, and 0.1% mercury chloride for 2 minutes, rinsed with distilled water, air dried, and kept in a hot air oven at 40ºc on blotting paper until all the water evaporated and became well dried for grinding. After drying, the plant materials were grounded using a mixer grinder into fine powder transferred into airtight containers with proper labeling, and stored at 4ºc for future use (Horablaga et al., 2023). The extraction process was done according to Altemimi et al., 2017. The 5g powder was mixed with 15 ml of the respective solvents (n-hexane, ethyl acetate, and methanol), and kept for 4-5 days on the platform shaker. The solvents used are based on their increasing polarity index. Then the extract was centrifuged at 10,000rpm for 5 minutes and filtered using No.1 Whatman filter paper.Keywords: cancer, phytomedicine, medicinal plants, oncology
Procedia PDF Downloads 76965 Leadership in the Emergence Paradigm: A Literature Review on the Medusa Principles
Authors: Everard van Kemenade
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Many quality improvement activities are planned. Leaders are strongly involved in missions, visions and strategic planning. They use, consciously or unconsciously, the PDCA-cycle, also know as the Deming cycle. After the planning, the plans are carried out and the results or effects are measured. If the results show that the goals in the plan have not been achieved, adjustments are made in the next plan or in the execution of the processes. Then, the cycle is run through again. Traditionally, the PDCA-cycle is advocated as a means to an end. However, PDCA is especially fit for planned, ordered, certain contexts. It fits with the empirical and referential quality paradigm. For uncertain, unordered, unplanned processes, something else might be needed instead of Plan-Do-Check-Act. Due to the complexity of our society, the influence of the context, and the uncertainty in our world nowadays, not every activity can be planned anymore. At the same time organisations need to be more innovative than ever. That provides leaders with ‘wicked tendencies’. However, that raises the question how one can innovate without being able to plan? Complexity science studies the interactions of a diverse group of agents that bring about change in times of uncertainty, e.g. when radical innovation is co-created. This process is called emergence. This research study explores the role of leadership in the emergence paradigm. Aim of the article is to study the way that leadership can support the emergence of innovation in a complex context. First, clarity is given on the concepts used in the research question: complexity, emergence, innovation and leadership. Thereafter a literature search is conducted to answer the research question. The topics ‘emergent leadership’ or ‘complexity leadership’ are chosen for an exploratory search in Google and Google Scholar using the berry picking method. Exclusion criterion is emergence in other disciplines than organizational development or in the meaning of ‘arising’. The literature search conducted gave 45 hits. Twenty-seven articles were excluded after reading the title and abstract because they did not research the topic of emergent leadership and complexity. After reading the remaining articles as a whole one more was excluded because the article used emergent in the limited meaning of ‗arising‘ and eight more were excluded because the topic did not match the research question of this article. That brings the total of the search to 17 articles. The useful conclusions from the articles are merged and grouped together under overarching topics, using thematic analysis. The findings are that 5 topics prevail when looking at possibilities for leadership to facilitate innovation: enabling, sharing values, dreaming, interacting, context sensitivity and adaptivity. Together they form In Dutch the acronym Medusa.Keywords: complexity science, emergence, leadership in the emergence paradigm, innovation, the Medusa principles
Procedia PDF Downloads 35964 Finite Element Analysis of Layered Composite Plate with Elastic Pin Under Uniaxial Load Using ANSYS
Authors: R. M. Shabbir Ahmed, Mohamed Haneef, A. R. Anwar Khan
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Analysis of stresses plays important role in the optimization of structures. Prior stress estimation helps in better design of the products. Composites find wide usage in the industrial and home applications due to its strength to weight ratio. Especially in the air craft industry, the usage of composites is more due to its advantages over the conventional materials. Composites are mainly made of orthotropic materials having unequal strength in the different directions. Composite materials have the drawback of delamination and debonding due to the weaker bond materials compared to the parent materials. So proper analysis should be done to the composite joints before using it in the practical conditions. In the present work, a composite plate with elastic pin is considered for analysis using finite element software Ansys. Basically the geometry is built using Ansys software using top down approach with different Boolean operations. The modelled object is meshed with three dimensional layered element solid46 for composite plate and solid element (Solid45) for pin material. Various combinations are considered to find the strength of the composite joint under uniaxial loading conditions. Due to symmetry of the problem, only quarter geometry is built and results are presented for full model using Ansys expansion options. The results show effect of pin diameter on the joint strength. Here the deflection and load sharing of the pin are increasing and other parameters like overall stress, pin stress and contact pressure are reducing due to lesser load on the plate material. Further material effect shows, higher young modulus material has little deflection, but other parameters are increasing. Interference analysis shows increasing of overall stress, pin stress, contact stress along with pin bearing load. This increase should be understood properly for increasing the load carrying capacity of the joint. Generally every structure is preloaded to increase the compressive stress in the joint to increase the load carrying capacity. But the stress increase should be properly analysed for composite due to its delamination and debonding effects due to failure of the bond materials. When results for an isotropic combination is compared with composite joint, isotropic joint shows uniformity of the results with lesser values for all parameters. This is mainly due to applied layer angle combinations. All the results are represented with necessasary pictorial plots.Keywords: bearing force, frictional force, finite element analysis, ANSYS
Procedia PDF Downloads 338963 Intrigues of Brand Activism versus Brand Antagonism in Rival Online Football Brand Communities: The Case of the Top Two Premier Football Clubs in Ghana
Authors: Joshua Doe, George Amoako
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Purpose: In an increasingly digital world, the realm of sports fandom has extended its borders, creating a vibrant ecosystem of online communities centered around football clubs. This study ventures into the intricate interplay of motivations that drive football fans to respond to brand activism and its profound implications for brand antagonism and engagement among two of Ghana's most revered premier football clubs. Methods: A sample of 459 fervent fans from these two rival clubs were engaged through self-administered questionnaires expertly distributed via social media and online platforms. Data was analysed, using PLS-SEM. Findings: The tapestry of motivations that weave through these online football communities is as diverse as the fans themselves. It becomes apparent that fans are propelled by a spectrum of incentives. They seek education, yearn for information, revel in entertainment, embrace socialization, and fortify their self-esteem through their interactions within these digital spaces. Yet, it is the nuanced distinction in these motivations that shapes the trajectory of brand antagonism and engagement. Surprisingly, the study reveals a remarkable pattern. Football fans, despite their fierce rivalries, do not engage in brand antagonism based on educational pursuits, information-seeking endeavors, or socialization. Instead, it is motivations rooted in entertainment and self-esteem that serve as the fertile grounds for brand antagonism. Paradoxically, it is these very motivations coupled with the desire for socialization that nurture brand engagement, manifesting as active support and advocacy for their chosen club brand. Originality: Our research charters new waters by extending the boundaries of existing theories in the field. The Technology Acceptance Uses and Gratifications Theory, and Social Identity Theory all find new dimensions within the context of online brand community engagement. This not only deepens our understanding of the multifaceted world of online football fandom but also invites us to explore the implications these insights carry within the digital realm. Contribution to Practice: For marketers, our findings offer a treasure trove of actionable insights. They beckon the development of targeted content strategies that resonate with fan motivations. The implementation of brand advocacy programs, fostering opportunities for socialization, and the effective management of brand antagonism emerge as pivotal strategies. Furthermore, the utilization of data-driven insights is poised to refine consumer engagement strategies and strengthen brand affinity. Future Studies: For future studies, we advocate for longitudinal, cross-cultural, and qualitative studies that could shed further light on this topic. Comparative analyses across different types of online brand communities, an exploration of the role of brand community leaders, and inquiries into the factors that contribute to brand community dissolution all beckon the research community. Furthermore, understanding motivation-specific antagonistic behaviors and the intricate relationship between information-seeking and engagement present exciting avenues for further exploration. This study unfurls a vibrant tapestry of fan motivations, brand activism, and rivalry within online football communities. It extends a hand to scholars and marketers alike, inviting them to embark on a journey through this captivating digital realm, where passion, rivalry, and engagement harmonize to shape the world of sports fandom as we know it.Keywords: online brand engagement, football fans, brand antagonism, motivations
Procedia PDF Downloads 68962 Changes in Cognition of Elderly People: A Longitudinal Study in Kanchanaburi Province, Thailand
Authors: Natchaphon Auampradit, Patama Vapattanawong, Sureeporn Punpuing, Malee Sunpuwan, Tawanchai Jirapramukpitak
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Longitudinal studies related to cognitive impairment in elderly are necessary for health promotion and development. The purposes of this study were (1) to examine changes in cognition of elderly over time and (2) to examine the impacts of changes in social determinants of health (SDH) toward changes in cognition of elderly by using the secondary data derived from the Kanchanaburi Demographic Surveillance System (KDSS) by the Institute for Population and Social Research (IPSR) which contained longitudinal data on individuals, households, and villages. Two selected projects included the Health and Social Support for Elderly in KDSS in 2007 and the Population, Economic, Social, Cultural, and Long-term Care Surveillance for Thai Elderly People’s Health Promotion in 2011. The samples were 586 elderly participated in both projects. SDH included living arrangement, social relationships with children, relatives, and friends, household asset-based wealth index, household monthly income, loans for livings, loans for investment, and working status. Cognitive impairment was measured by category fluency and delayed recall. This study employed Generalized Estimating Equation (GEE) model to investigate changes in cognition by taking SDH and other variables such as age, gender, marital status, education, and depression into the model. The unstructured correlation structure was selected to use for analysis. The results revealed that 24 percent of elderly had cognitive impairment at baseline. About 13 percent of elderly still had cognitive impairment during 2007 until 2011. About 21 percent and 11 percent of elderly had cognitive decline and cognitive improvement, respectively. The cross-sectional analysis showed that household asset-based wealth index, social relationship with friends, working status, age, marital status, education, and depression were significantly associated with cognitive impairment. The GEE model revealed longitudinal effects of household asset-based wealth index and working status against cognition during 2007 until 2011. There was no longitudinal effect of social conditions against cognition. Elderly living with richer household asset-based wealth index, still being employed, and being younger were less likely to have cognitive impairment. The results strongly suggested that poorer household asset-based wealth index and being unemployed were served as a risk factor for cognitive impairment over time. Increasing age was still the major risk for cognitive impairment as well.Keywords: changes in cognition, cognitive impairment, elderly, KDSS, longitudinal study
Procedia PDF Downloads 146961 Technological Affordances of a Mobile Fitness Application- A Role of Escapism and Social Outcome Expectation
Authors: Inje Cho
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The leading health risks threatening the world today are associated with a modern lifestyle characterized by sedentary behavior, stress, anxiety, and an obesogenic food environment. To counter this alarming trend, the Centers for Disease Control and Prevention have proffered Physical Activity guidelines to bolster physical engagement. Concurrently, the burgeon of smartphones and mobile applications has witnessed a proliferation of fitness applications aimed at invigorating exercise adherence and real-time activity monitoring. Grounded in the Uses and gratification theory, this study delves into the technological affordances of mobile fitness applications, discerning the mediating influences of escapism and social outcome expectations on attitudes and exercise intention. The theory explains how individuals employ distinct communication mediums to satiate their exigencies and desires. Technological affordances manifest as attributes of emerging technologies that galvanize personal engagement in physical activities. Several features of mobile fitness applications include affordances for goal setting, virtual rewards, peer support, and exercise information. Escapism, denoting the inclination to disengage from normal routines, has emerged as a salient motivator for the consumption of new media. This study postulates that individual’s perceptions technological affordances within mobile fitness applications, can affect escapism and social outcome expectations, potentially influencing attitude, and behavior formation. Thus, the integrated model has been developed to empirically examine the interrelationships between technological affordances, escapism, social outcome expectations, and exercise intention. Structural Equation Modelling serves as the methodological tool, and a cohort of 400 Fitbit users shall be enlisted from the Prolific, data collection platform. A sequence of multivariate data analyses will scrutinize both the measurement and hypothesized structural models. By delving into the effects of mobile fitness applications, this study contributes to the growing of new media studies in sport management. Moreover, the novel integration of the uses and gratification theory, technological affordances, via the prism of escapism, illustrates the dynamics that underlies mobile fitness user’s attitudes and behavioral intentions. Therefore, the findings from this study contribute to theoretical understanding and provide pragmatic insights to developers and practitioners in optimizing the impact of mobile fitness applications.Keywords: technological affordances, uses and gratification, mobile fitness apps, escapism, physical activity
Procedia PDF Downloads 82960 Self-Assembling Layered Double Hydroxide Nanosheets on β-FeOOH Nanorods for Reducing Fire Hazards of Epoxy Resin
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Epoxy resins (EP), one of the most important thermosetting polymers, is widely applied in various fields due to its desirable properties, such as excellent electrical insulation, low shrinkage, outstanding mechanical stiffness, satisfactory adhesion and solvent resistance. However, like most of the polymeric materials, EP has the fatal drawbacks including inherent flammability and high yield of toxic smoke, which restricts its application in the fields requiring fire safety. So, it is still a challenge and an interesting subject to develop new flame retardants which can not only remarkably improve the flame retardancy, but also render modified resins low toxic gases generation. In recent work, polymer nanocomposites based on nanohybrids that contain two or more kinds of nanofillers have drawn intensive interest, which can realize performance enhancements. The realization of previous hybrids of carbon nanotubes (CNTs) and molybdenum disulfide provides us a novel route to decorate layered double hydroxide (LDH) nanosheets on the surface of β-FeOOH nanorods; the deposited LDH nanosheets can fill the network and promote the work efficiency of β-FeOOH nanorods. Moreover, the synergistic effects between LDH and β-FeOOH can be anticipated to have potential applications in reducing fire hazards of EP composites for the combination of condense-phase and gas-phase mechanism. As reported, β-FeOOH nanorods can act as a core to prepare hybrid nanostructures combining with other nanoparticles through electrostatic attraction through layer-by-layer assembly technique. In this work, LDH nanosheets wrapped β-FeOOH nanorods (LDH-β-FeOOH) hybrids was synthesized by a facile method, with the purpose of combining the characteristics of one dimension (1D) and two dimension (2D), to improve the fire resistance of epoxy resin. The hybrids showed a well dispersion in EP matrix and had no obvious aggregation. Thermogravimetric analysis and cone calorimeter tests confirmed that LDH-β-FeOOH hybrids into EP matrix with a loading of 3% could obviously improve the fire safety of EP composites. The plausible flame retardancy mechanism was explored by thermogravimetric infrared (TG-IR) and X-ray photoelectron spectroscopy. The reasons were concluded: condense-phase and gas-phase. Nanofillers were transferred to the surface of matrix during combustion, which could not only shield EP matrix from external radiation and heat feedback from the fire zone, but also efficiently retard transport of oxygen and flammable pyrolysis.Keywords: fire hazards, toxic gases, self-assembly, epoxy
Procedia PDF Downloads 175959 Progressive Damage Analysis of Mechanically Connected Composites
Authors: Şeyma Saliha Fidan, Ozgur Serin, Ata Mugan
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While performing verification analyses under static and dynamic loads that composite structures used in aviation are exposed to, it is necessary to obtain the bearing strength limit value for mechanically connected composite structures. For this purpose, various tests are carried out in accordance with aviation standards. There are many companies in the world that perform these tests in accordance with aviation standards, but the test costs are very high. In addition, due to the necessity of producing coupons, the high cost of coupon materials, and the long test times, it is necessary to simulate these tests on the computer. For this purpose, various test coupons were produced by using reinforcement and alignment angles of the composite radomes, which were integrated into the aircraft. Glass fiber reinforced and Quartz prepreg is used in the production of the coupons. The simulations of the tests performed according to the American Society for Testing and Materials (ASTM) D5961 Procedure C standard were performed on the computer. The analysis model was created in three dimensions for the purpose of modeling the bolt-hole contact surface realistically and obtaining the exact bearing strength value. The finite element model was carried out with the Analysis System (ANSYS). Since a physical break cannot be made in the analysis studies carried out in the virtual environment, a hypothetical break is realized by reducing the material properties. The material properties reduction coefficient was determined as 10%, which is stated to give the most realistic approach in the literature. There are various theories in this method, which is called progressive failure analysis. Because the hashin theory does not match our experimental results, the puck progressive damage method was used in all coupon analyses. When the experimental and numerical results are compared, the initial damage and the resulting force drop points, the maximum damage load values , and the bearing strength value are very close. Furthermore, low error rates and similar damage patterns were obtained in both test and simulation models. In addition, the effects of various parameters such as pre-stress, use of bushing, the ratio of the distance between the bolt hole center and the plate edge to the hole diameter (E/D), the ratio of plate width to hole diameter (W/D), hot-wet environment conditions were investigated on the bearing strength of the composite structure.Keywords: puck, finite element, bolted joint, composite
Procedia PDF Downloads 105958 Perceived Restorativeness Scale– 6: A Short Version of the Perceived Restorativeness Scale for Mixed (or Mobile) Devices
Authors: Sara Gallo, Margherita Pasini, Margherita Brondino, Daniela Raccanello, Roberto Burro, Elisa Menardo
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Most of the studies on the ability of environments to recover people’s cognitive resources have been conducted in laboratory using simulated environments (e.g., photographs, videos, or virtual reality), based on the implicit assumption that exposure to simulated environments has the same effects of exposure to real environments. However, the technical characteristics of simulated environments, such as the dynamic or static characteristics of the stimulus, critically affect their perception. Measuring perceived restorativeness in situ rather than in laboratory could increase the validity of the obtained measurements. Personal mobile devices could be useful because they allow accessing immediately online surveys when people are directly exposed to an environment. At the same time, it becomes important to develop short and reliable measuring instruments that allow a quick assessment of the restorative qualities of the environments. One of the frequently used self-report measures to assess perceived restorativeness is the “Perceived Restorativeness Scale” (PRS) based on Attention Restoration Theory. A lot of different versions have been proposed and used according to different research purposes and needs, without studying their validity. This longitudinal study reported some preliminary validation analyses on a short version of original scale, the PRS-6, developed to be quick and mobile-friendly. It is composed of 6 items assessing fascination and being-away. 102 Italian university students participated to the study, 84% female with age ranging from 18 to 47 (M = 20.7; SD = 2.9). Data were obtained through a survey online that asked them to report their perceived restorativeness of the environment they were in (and the kind of environment) and their positive emotion (Positive and Negative Affective Schedule, PANAS) once a day for seven days. Cronbach alpha and item-total correlations were used to assess reliability and internal consistency. Confirmatory Factor Analyses (CFA) models were run to study the factorial structure (construct validity). Correlation analyses between PRS and PANAS scores were used to check discriminant validity. In the end, multigroup CFA models were used to study measurement invariance (configural, metric, scalar, strict) between different mobile devices and between day of assessment. On the whole, the PRS-6 showed good psychometric proprieties, similar to those of the original scale, and invariance across devices and days. These results suggested that the PRS-6 could be a valid alternative to assess perceived restorativeness when researchers need a brief and immediate evaluation of the recovery quality of an environment.Keywords: restorativeness, validation, short scale development, psychometrics proprieties
Procedia PDF Downloads 255957 Colorful Ethnoreligious Map of Iraq and the Current Situation of Minorities in the Country
Authors: Meszár Tárik
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The aim of the study is to introduce the minority groups living in Iraq and to shed light on their current situation. The Middle East is a rather heterogeneous region in ethnic terms. It includes many ethnic, national, religious, linguistic, or ethnoreligious groups. The relationship between the majority and minority is the main cause of various conflicts in the region. It seems that most of the post-Ottoman states have not yet developed a unified national identity capable of integrating their multi-ethnic societies. The issue of minorities living in the Middle East is highly politicized and controversial, as the various Arab states consider the treatment of minorities as their internal affair, do not recognize discrimination or even deny the existence of any kind of minorities on their territory. This attitude of the Middle Eastern states may also be due to the fact that the minority issue can be abused and can serve as a reference point for the intervention policies of Western countries at any time. Methodologically, the challenges of these groups are perceived through the manifestos of prominent individuals and organizations belonging to minorities. The basic aim is to present the minorities’ own history in dealing with the issue. It also introduces the different ethnic and religious minorities in Iraq and analyzes their situation during the operation of the terrorist organization „Islamic State” and in the aftermath. It is clear that the situation of these communities deteriorated significantly with the advance of ISIS, but it is also clear that even after the expulsion of the militant group, we cannot necessarily report an improvement in this area, especially in terms of the ability of minorities to assert their interests and physical security. The emergence of armed militias involved in the expulsion of ISIS sometimes has extremely negative effects on them. Until the interests of non-Muslims are adequately represented at the local level and in the legislature, most experts and advocates believe that little will change in their situation. When conflicts flare, many Iraqi citizens usually leave Iraq, but because of the poor public security situation (threats from terrorist organizations, interventions by other countries), emigration causes serious problems not only outside the country’s borders but also within the country. Another ominous implication for minorities is that their communities are very slow if ever, to return to their homes after fleeing their own settlements. An important finding of the study is that this phenomenon is changing the face of traditional Iraqi settlements and threatens to plunge groups that have lived there for thousands of years into the abyss of history. Therefore, we not only present the current situation of minorities living in Iraq but also discuss their future possibilities.Keywords: Middle East, Iraq, Islamic State, minorities
Procedia PDF Downloads 91956 MicroRNA-1246 Expression Associated with Resistance to Oncogenic BRAF Inhibitors in Mutant BRAF Melanoma Cells
Authors: Jae-Hyeon Kim, Michael Lee
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Intrinsic and acquired resistance limits the therapeutic benefits of oncogenic BRAF inhibitors in melanoma. MicroRNAs (miRNA) regulate the expression of target mRNAs by repressing their translation. Thus, we investigated miRNA expression patterns in melanoma cell lines to identify candidate biomarkers for acquired resistance to BRAF inhibitor. Here, we used Affymetrix miRNA V3.0 microarray profiling platform to compare miRNA expression levels in three cell lines containing BRAF inhibitor-sensitive A375P BRAF V600E cells, their BRAF inhibitor-resistant counterparts (A375P/Mdr), and SK-MEL-2 BRAF-WT cells with intrinsic resistance to BRAF inhibitor. The miRNAs with at least a two-fold change in expression between BRAF inhibitor-sensitive and –resistant cell lines, were identified as differentially expressed. Averaged intensity measurements identified 138 and 217 miRNAs that were differentially expressed by 2 fold or more between: 1) A375P and A375P/Mdr; 2) A375P and SK-MEL-2, respectively. The hierarchical clustering revealed differences in miRNA expression profiles between BRAF inhibitor-sensitive and –resistant cell lines for miRNAs involved in intrinsic and acquired resistance to BRAF inhibitor. In particular, 43 miRNAs were identified whose expression was consistently altered in two BRAF inhibitor-resistant cell lines, regardless of intrinsic and acquired resistance. Twenty five miRNAs were consistently upregulated and 18 downregulated more than 2-fold. Although some discrepancies were detected when miRNA microarray data were compared with qPCR-measured expression levels, qRT-PCR for five miRNAs (miR-3617, miR-92a1, miR-1246, miR-1936-3p, and miR-17-3p) results showed excellent agreement with microarray experiments. To further investigate cellular functions of miRNAs, we examined effects on cell proliferation. Synthetic oligonucleotide miRNA mimics were transfected into three cell lines, and proliferation was quantified using a colorimetric assay. Of the 5 miRNAs tested, only miR-1246 altered cell proliferation of A375P/Mdr cells. The transfection of miR-1246 mimic strongly conferred PLX-4720 resistance to A375P/Mdr cells, implying that miR-1246 upregulation confers acquired resistance to BRAF inhibition. We also found that PLX-4720 caused much greater G2/M arrest in A375P/Mdr cells transfected with miR-1246mimic than that seen in scrambled RNA-transfected cells. Additionally, miR-1246 mimic partially caused a resistance to autophagy induction by PLX-4720. These results indicate that autophagy does play an essential death-promoting role inPLX-4720-induced cell death. Taken together, these results suggest that miRNA expression profiling in melanoma cells can provide valuable information for a network of BRAF inhibitor resistance-associated miRNAs.Keywords: microRNA, BRAF inhibitor, drug resistance, autophagy
Procedia PDF Downloads 329955 Lab-on-Chip Multiplexed qPCR Analysis Utilizing Melting Curve Analysis Detects Up to 144 Alleles with Sub-hour Turn-around Time
Authors: Jeremy Woods, Fanqing Chen
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Rapid genome testing can provide results in at best hours to days, though there are certain clinical decisions that could be guided by genetic test results that need results in hours to minutes. As such, methods of genetic Point of Care Testing (POCT) are required if genetic data is to guide management in illnesses in a wide variety of critical and emergent medical situations such as neonatal sepsis, chemotherapy administration in endometrial cancer, and glucose-6-phosphate dehydrogenase deficiency (G6PD)-associated neonatal hyperbilirubinemia. As such, we developed a POCT “lab-on-chip” technology capable of identifying up to 144 alleles in under an hour. This test required no specialized training to utilize and is suitable to deployment in clinics and hospitals for use by non-laboratory personnel such as nurses. We developed a multiplexed qPCR-based sample-to-answer system with melting curve analysis capable of detecting up to 144 alleles utilizing the Kelliop RapidSeq126 PCR platform combined with a single-use microfluidic cartridge. The RapidSeq126 is the size of a standard desktop printer and the microfluidic cartridges are smaller than a deck of playing cards. Thus the system was deployable in the outpatient setting for clinical trials of MT-RNR1 genotyping. The sample (buccal swab from volunteers or plasmids in media) used for DNA extraction was placed in the cartridge sample inlet prior to inserting the cartridge into the RapidSeq126. The microfluidic cartridge was composed of heat resistant polymer with a sample inlet, 100um conduits, liquid and solid reagents, valves, extraction chamber, lyophilization chamber, 12 PCR reaction chambers, and a waste chamber. No human effort was required for processing the sample and performing the assay other than placing the sample in the cartridge and placing the cartridge in the RapidSeq126. The RapidSeq126 has demonstrated ex vivo detection in plasmids and in vivo detection from human volunteer samples of up to 144 alleles per microfluidic cartridge used and did not require specialized laboratory training to operate. Efficacy was proven for several applications, such as multiple microsatellite instability (MSI) sites (SULF/RYR3/MRE11/ACVR2A/DIDO1/SEC31A/BTBD7), endometrial cancer POLE exonuclease domain (EMD) mutation status, and G6PD variants such as those commonly associated with hemolysis (c.202G>A, c.376A>G, c.680G>A>T, c.968T>C, 404A>C, c.871G>A). The RapidSeq126 system was also able to identify the three MT-RNR1 variants associated with aminoglycoside-induced sensorineural hearing loss (m.1555A>G, m.1095T>C, m.1494C>T). Results were provided in under an hour in a sample-to-answer fashion requiring no processing other than inserting the cartridge with the sample into the RapidSeq126. Results were provided in a digital, HL7-compliant format suitable for interfacing with Electronic Healthcare Record (EHR). The RapidSeq126 system provides a solution for emergency and critical medical situations requiring results in a matter of minutes to hours. The HL7-compliant data format of results enables the RapidSeq126 to interface directly with EHRs to generate best practice advisories and further reduce errors and time to diagnosis by providing digital results.Keywords: genetic testing, pharmacogenomics, point of care testing, rapid genetic testing
Procedia PDF Downloads 16954 High Performance Lithium Ion Capacitors from Biomass Waste-Derived Activated Carbon
Authors: Makhan Maharjan, Mani Ulaganathan, Vanchiappan Aravindan, Srinivasan Madhavi, Jing-Yuan Wang, Tuti Mariana Lim
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The ever-increasing energy demand has made research to develop high performance energy storage systems that are able to fulfill energy needs. Supercapacitors have potential applications as portable energy storage devices. In recent years, there have been huge research interests to enhance the performances of supercapacitors via exploiting novel promising carbon precursors, tailoring textural properties of carbons, exploiting various electrolytes and device types. In this work, we employed orange peel (waste material) as the starting material and synthesized activated carbon by pyrolysis of KOH impregnated orange peel char at 800 °C in argon atmosphere. The resultant orange peel-derived activated carbon (OP-AC) exhibited BET surface area of 1,901 m² g-1, which is the highest surface area so far reported for the orange peel. The pore size distribution (PSD) curve exhibits the pores centered at 11.26 Å pore width, suggesting dominant microporosity. The high surface area OP-AC accommodates more ions in the electrodes and its well-developed porous structure facilitates fast diffusion of ions which subsequently enhance electrochemical performance. The OP-AC was studied as positive electrode in combination with different negative electrode materials, such as pre-lithiated graphite (LiC6) and Li4Ti5O12 for making hybrid capacitors. The lithium ion capacitor (LIC) fabricated using OP-AC with pre-lithiated graphite delivered high energy density of ~106 Wh kg–1. The energy density for OP-AC||Li4Ti5O12 capacitor was ~35 Wh kg⁻¹. For comparison purpose, configuration of OP-AC||OP-AC capacitors were studied in both aqueous (1M H2SO4) and organic (1M LiPF6 in EC-DMC) electrolytes, which delivered the energy density of 8.0 Wh kg⁻¹ and 16.3 Wh kg⁻¹, respectively. The cycling retentions obtained at current density of 1 A g⁻¹ were ~85.8, ~87.0 ~82.2 and ~58.8% after 2500 cycles for OP-AC||OP-AC (aqueous), OP-AC||OP-AC (organic), OP-AC||Li4Ti5O12 and OP-AC||LiC6 configurations, respectively. In addition, characterization studies were performed by elemental and proximate composition, thermogravimetry analysis, field emission-scanning electron microscopy, Raman spectra, X-ray diffraction (XRD) pattern, Fourier transform-infrared, X-ray photoelectron spectroscopy (XPS) and N2 sorption isotherms. The morphological features from FE-SEM exhibited well-developed porous structures. Two typical broad peaks observed in the XRD framework of the synthesized carbon implies amorphous graphitic structure. The ratio of 0.86 for ID/IG in Raman spectra infers high degree of graphitization in the sample. The band spectra of C 1s in XPS display the well resolved peaks related to carbon atoms in various chemical environments. The presence of functional groups is also corroborated from the FTIR spectroscopy. Characterization studies revealed the synthesized carbon to be promising electrode material towards the application for energy storage devices. Overall, the intriguing properties of OP-AC make it a new alternative promising electrode material for the development of high energy lithium ion capacitors from abundant, low-cost, renewable biomass waste. The authors gratefully acknowledge Agency for Science, Technology and Research (A*STAR)/ Singapore International Graduate Award (SINGA) and Nanyang Technological University (NTU), Singapore for funding support.Keywords: energy storage, lithium-ion capacitors, orange peels, porous activated carbon
Procedia PDF Downloads 230953 The Prospects of Optimized KOH/Cellulose 'Papers' as Hierarchically Porous Electrode Materials for Supercapacitor Devices
Authors: Dina Ibrahim Abouelamaiem, Ana Jorge Sobrido, Magdalena Titirici, Paul R. Shearing, Daniel J. L. Brett
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Global warming and scarcity of fossil fuels have had a radical impact on the world economy and ecosystem. The urgent need for alternative energy sources has hence elicited an extensive research for exploiting efficient and sustainable means of energy conversion and storage. Among various electrochemical systems, supercapacitors attracted significant attention in the last decade due to their high power supply, long cycle life compared to batteries and simple mechanism. Recently, the performance of these devices has drastically improved, as tuning of nanomaterials provided efficient charge and storage mechanisms. Carbon materials, in various forms, are believed to pioneer the next generation of supercapacitors due to their attractive properties that include high electronic conductivities, high surface areas and easy processing and functionalization. Cellulose has eco-friendly attributes that are feasible to replace man-made fibers. The carbonization of cellulose yields carbons, including activated carbon and graphite fibers. Activated carbons successively are the most exploited candidates for supercapacitor electrode materials that can be complemented with pseudocapacitive materials to achieve high energy and power densities. In this work, the optimum functionalization conditions of cellulose have been investigated for supercapacitor electrode materials. The precursor was treated with potassium hydroxide (KOH) at different KOH/cellulose ratios prior to the carbonization process in an inert nitrogen atmosphere at 850 °C. The chalky products were washed, dried and characterized with different techniques including transmission electron microscopy (TEM), x-ray tomography and nitrogen adsorption-desorption isotherms. The morphological characteristics and their effect on the electrochemical performances were investigated in two and three-electrode systems. The KOH/cellulose ratios of 0.5:1 and 1:1 exhibited the highest performances with their unique hierarchal porous network structure, high surface areas and low cell resistances. Both samples acquired the best results in three-electrode systems and coin cells with specific gravimetric capacitances as high as 187 F g-1 and 20 F g-1 at a current density of 1 A g-1 and retention rates of 72% and 70%, respectively. This is attributed to the morphology of the samples that constituted of a well-balanced micro-, meso- and macro-porosity network structure. This study reveals that the electrochemical performance doesn’t solely depend on high surface areas but also an optimum pore size distribution, specifically at low current densities. The micro- and meso-pore contribution to the final pore structure was found to dominate at low KOH loadings, reaching ‘equilibrium’ with macropores at the optimum KOH loading, after which macropores dictate the porous network. The wide range of pore sizes is detrimental for the mobility and penetration of electrolyte ions in the porous structures. These findings highlight the influence of various morphological factors on the double-layer capacitances and high performance rates. In addition, they open a platform for the investigation of the optimized conditions for double-layer capacitance that can be coupled with pseudocapacitive materials to yield higher energy densities and capacities.Keywords: carbon, electrochemical performance, electrodes, KOH/cellulose optimized ratio, morphology, supercapacitor
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