Search results for: higher education in Malaysia
4122 Evaluation of Surgical Site Infection in Bile Spillage Cases Compared to Non Bile Spillage Cases Following Laparoscopic Cholecystectomy
Authors: Ishwor Paudel, Pratima Gautam, Sandeep Bhattarai
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Bile spillage occurs frequently during laparoscopic cholecystectomy yet its impact on postoperative outcomes remains unknown. It might not be as innocuous as some surgeons tend to believe and in fact, might be associated with post-operative surgical site infections (SSI). It often leads to patient dissatisfaction, emergency department visits, with subsequent readmission and additional procedures. While some authors found no increase in SSI following bile spillage (BS) compared to non-bile spillage cases, others found bile spillage to be associated with SSI. Therefore we sought to examine whether bile spillage is indeed associated with an increased risk of postoperative wound infections after laparoscopic cholecystectomy. I hypothesize that patients who experience BS during operation, have an increased risk of SSI compared to those who do not. This is a prospective observational study conducted in the Department of Surgery, Patan Hospital over a period of one year. Patients undergoing Laparoscopic cholecystectomy were included and bile spillage, if happened was noted. All cases were followed up for 30 days and SSI was diagnosed as per CDC-defined criteria. Fisher’s test was applied to compare SSI in bile spillage versus non-bile spillage cases. A total of 112 patients were included in the final analysis. Bile spillage occurred in 20 cases and was absent in the rest i.e.92 cases. Among bile spillage cases, SSI was found in 4 cases (20%), whereas in nonbile spillage cases, SSI was found in 8 cases (8.7%). However, it was statistically not significant (p-value>0.05). Eleven (92%) cases were superficial SSI and one was an organ-space infection. No mortality or 30-day readmission. Spillage of Gallbladder content does not lead to an increase in SSIs. However as the rate of SSI is still higher, Surgeons should be careful to avoid iatrogenic gallbladder perforation and in case of bile spillage thorough peritoneal irrigation with normal saline should be done.Keywords: organ space infection, Laparoscopic cholecystectomy, biliary spillage, surgical site infection
Procedia PDF Downloads 764121 Electrospun Fibers Made from Biopolymers (Cellulose Acetate/Chitosan) for Metals Recovery
Authors: Mauricio Gómez, Esmeralda López, Ian Becar, Jaime Pizarro, Paula A. Zapata
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A biodegradable material is developed with adsorptive capacity for metals ion for intended use in mining tailings mitigating the environmental impact with economic retribution, two types of fibers were elaborated by electrospinning: (1) a cellulose acetate (CA) matrix and (2) a cellulose acetate (CA)/chitosan (CH) matrix evaluating the effect of CH in CA on its physicochemical properties. Through diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) the incorporation of chitosan in the matrix was identified, observing the band of the amino group at 1500 - 1600 [cm-1]. By scanning electron microscopy (SEM), Hg porosimetry, and CO2 isotherm at 273 [K], the intrafiber microporosity and interfiber macroporosity were identified, with an increase in the distribution of macropores for CA/CH fibers. In the tensile test, CH into the matrix produces a more ductile and tenacious behavior, where the % elongation at break increased by 33% with the other parameters constant. Thermal analysis by differential scanning calorimetry (DSC) and Thermogravimetric Analysis (TGA) showed that the incorporation of chitosan produces higher retention of water molecules due to the functional groups (amino groups (- NH3)), but there is a decrease in the specific heat and thermoplastic properties of the matrix since the glass transition temperature and softening temperature disappear. The effect of the optimum pH for CA and CA/CH fibers were studied in a batch system. In the adsorption kinetic study, the best isotherm model adapted to the experimental results corresponds to the Sips model and the kinetics corresponds to pseudo-second orderKeywords: environmental materials, wastewater treatment, electrospun fibers, biopolymers (cellulose acetate/chitosan), metals recovery
Procedia PDF Downloads 784120 The Colorectal Cancer in Patients of Eastern Algeria
Authors: S. Tebibel, C. Mechati, S. Messaoudi
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Algeria is currently experiencing the same rate of cancer progression as that registered these last years in the western countries. Colorectal cancer, constituting increasingly a major public health problem, is the most common form of cancer after breast and Neck-womb cancer at the woman and prostate cancer at the man. Our work is based on a retrospective study to determine the cases of colorectal cancer through eastern Algeria. Our goal is to carry out an epidemiological, histological and immune- histochemical study to investigate different techniques for the diagnosis of colorectal cancer and their interests and specific in detecting the disease. The study includes 110 patients (aged between 20 to 87 years) with colorectal cancer where the inclusions and exclusions criteria were established. In our study, colorectal cancer, expresses a male predominance, with a sex ratio of 1, 99 and the most affected age group is between 50 and 59 years. We noted that the colon cancer rate is higher than rectal cancer rate, whose frequencies are respectively 60,91 % and 39,09 %. In the series of colon cancer, the ADK lieberkunien is histological the most represented type, or 85,07 % of all cases. In contrast, the proportion of ADK mucinous (colloid mucous) is only 1,49% only. Well-differentiated ADKS, are very significant in our series, they represent 83,58 % of cases. Adenocarcinoma moderately and poorly differentiated, whose proportions are respectively 2,99 % and 0.05 %. For histological varieties of rectal ADK, we see in our workforce that ADK lieberkunien represent the most common histological form, or 76,74%, while the mucosal colloid is 13,95 %. Research of the mutation on the gene encoding K-ras, a major step in the targeted therapy of colorectal cancers, is underway in our study. Colorectal cancer is the subject of much promising research concern: the evaluation of new therapies (antiangiogenic monoclonal antibodies), the search for predictors of sensitivity to chemotherapy and new prognostic markers using techniques of molecular biology and proteomics.Keywords: adenocarcinoma, age, colorectal cancer, epidemiology, histological section, sex
Procedia PDF Downloads 3434119 A Feasibility Study on Producing Bio-Coal from Orange Peel Residue by Using Torrefaction
Authors: Huashan Tai, Chien-Hui Lung
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Nowadays people use massive fossil fuels which not only cause environmental impacts and global climate change, but also cause the depletion of non-renewable energy such as coal and oil. Bioenergy is currently the most widely used renewable energy, and agricultural waste is one of the main raw materials for bioenergy. In this study, we use orange peel residue, which is easier to collect from agricultural waste to produce bio-coal by torrefaction. The orange peel residue (with 25 to 30% moisture) was treated by torrefaction, and the experiments were conducted with initial temperature at room temperature (approximately at 25° C), with heating rates of 10, 30, and 50°C / min, with terminal temperatures at 150, 200, 250, 300, 350℃, and with residence time of 10, 20, and 30 minutes. The results revealed that the heating value, ash content and energy densification ratio of the solid products after torrefaction are in direct proportion to terminal temperatures and residence time, and are inversely proportional to heating rates. The moisture content, solid mass yield, energy yield, and volumetric energy density of the solid products after torrefaction are inversely proportional to terminal temperatures and residence time, and are in direct proportion to heating rates. In conclusion, we found that the heating values of the solid products were 1.3 times higher than those of the raw orange peels before torrefaction, and the volumetric energy densities were increased by 1.45 times under operating parameters with terminal temperature at 250°C, residence time of 10 minutes, and heating rate of 10°C / min of torrefaction. The results indicated that the residue of orange peel treated by torrefaction improved its energy density and fuel properties, and became more suitable for bio-fuel applications.Keywords: biomass energy, orange, torrefaction
Procedia PDF Downloads 2884118 Review of Sulfur Unit Capacity Expansion Options
Authors: Avinashkumar Karre
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Sulfur recovery unit, most commonly called as Claus process, is very significant gas desulfurization process unit in refinery and gas industries. Explorations of new natural gas fields, refining of high-sulfur crude oils, and recent crude expansion projects are needing capacity expansion of Claus unit for many companies around the world. In refineries, the sulphur recovery units take acid gas from amine regeneration units and sour water strippers, converting hydrogen sulfide to elemental sulfur using the Claus process. The Claus process is hydraulically limited by mass flow rate. Reducing the pressure drop across control valves, flow meters, lines, knock-out drums, and packing improves the capacity. Oxygen enrichment helps improve the capacity by removing nitrogen, this is more commonly done on all capacity expansion projects. Typical upgrades required due to oxygen enrichment are new burners, new refractory in thermal reactor, resizing of 1st condenser, instrumentation changes, and steam/condensate heat integration. Some other capacity expansion options typically considered are tail gas compressor, replacing air blower with higher head, hydrocarbon minimization in the feed, water removal, and ammonia removal. Increased capacity related upgrades in sulfur recovery unit also need changes in the tail gas treatment unit, typical changes include improvement to quench tower duty, packing area upgrades in quench and absorber towers and increased amine circulation flow rates.Keywords: Claus process, oxygen enrichment, sulfur recovery unit, tail gas treatment unit
Procedia PDF Downloads 1234117 Critical Success Factors of OCOP Business Model in Pattani Province Thailand: A Qualitative Approach
Authors: Poonsook Thatchaopas, Nik Kamariah Nikmat, Nattakarn Eakuru
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Since 2003, the Thai Government has implemented several initiatives to encourage and incubate entrepreneurial skills and motivation among her citizens. One of the initiatives is the “One College One Product” business model or well known as ‘OCOP’, launched by the Vocational Education Commission to encourage partnership between college students to choose at least one product for business venture. In line with this mission, several business enterprises were established such as food products, restaurants, spa, Thai massage, minimart, computer maintenance, karaoke centre, internet café, mini theater etc. Currently, these business incubator projects can be observed at 404 vocational colleges and 21 incubation centres to encourage entrepreneurial small and medium enterprise (SME) development. However, the number of successful OCOP projects is still minimal. Out of the 404 individual OCOP projects at Vocational Colleges around Thailand, very few became successful. The objective of this paper is to identify the critical success factors needed to be a successful OCOP business entrepreneur. This study uses qualitative method by interviewing business partners of an OCOP business called Crispy Roti Krua Acheeva Brand (CRKAB). It is a snack food company that is developed at Pattani Vocational College in South Thailand. This project was initiated by three female entrepreneurs who were alumni student cum owners of the CRKAB. The finding shows that the main critical success factors are self-confidence, creativity or innovativeness, knowledge, skills and perseverance. Additionally, they reiterated that the keys to business success are product quality, perceived price, promotion, branding, new packaging to increase sales and continuous developments. The results implies for a student business SME to be successful, the company should have credible partners and effective marketing plan.Keywords: student entrepreneurship, business incubator, food industry, qualitative, Thailand
Procedia PDF Downloads 3914116 The Imperative for Disability Studies as an Independent Area of Enquiry in Indian Academia
Authors: Anita Ghai
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The present paper explores the imperative to establish disability studies as an independent area of academic inquiry in India through the establishment of specific programmes in disability studies. The case study of the efforts made by the Ambedkar University, Delhi, to develop such programs and courses shall be used to substantiate this imperative as well as to explore some of the challenges entailed. The paper shall explore the certain extent aspects of relevant scholarship in the area of disability studies in India today and critically reflect on the perspectives of disability in this scholarship. The study of disability in India has hitherto been the prerogative of special education, rehabilitation psychology, and social work departments. While instances of these departments adopting critical approaches to disability can be identified, their empirical focus has perpetuated the production of disability as the site of suffering and oppression. The complex cultural, phenomenological, historical and economic discourses within which disability is embedded can be better captured within distinctive programmes that have disability sui generis as their focus. Such programs would foreground disability as an epistemology, which universalizes the study of disability from disabled people alone to an analysis of various other groups who have been historically marginalized. It will also play an important role in recuperating disability from a state of alterity. The interdisciplinary nature of disability studies offers an opportunity to integrate perspectives from the humanities and the social sciences in the proposed programs. Some of the challenges or rather aspects of reflection that emerge in the course of developing these programs are the criteria for determining the suitability of faculty to teach these programs and the challenges in identifying faculty and in addressing any apprehensions about career prospects that prospective students might have. The manner in which these concerns are being addressed through the collaboration of expertise as well as through the interdisciplinary and flexible nature of the program shall be addressed in the course of the paper. In conclusion, the paper shall foreground the need for disability studies programs in India, the re-appropriation of existing scholarship in the process of formulation these programs, emerging concerns and the manner in which these concerns will be addressed.Keywords: academia, disability studies, epistemology, India
Procedia PDF Downloads 1444115 Green Synthesis of Silver Nanoparticles with Aqueous Extract of Moringa oleifera Lam Leaves and Its Ameliorative Effect on Benign Prostatic Hyperplasia in Wistar Rat
Authors: Rotimi Larayetana, Yahaya Abdulrazaq, Oladunni O. Falola, Abayomi Ajayi
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The aim of this study was to perform green synthesis of silver nanoparticles (AgNPs) with the aqueous extract of Moringa oleifera Lam (M oleifera) leaves and determine its effects on benign prostatic hyperplasia in Wistar rats. Silver nitrate (AgNO₃) solution was reduced using the aqueous extract of Moringa oleifera Lam leaves, the resultant biogenic AgNPs were characterized by Fourier transformed infrared spectrophotometric, SEM, TEM and X-ray diffraction analysis. Animal experiments involved thirty (30) adult male Wistar rats randomly divided into five groups (A to E; n ₌ 5). Group A received only subcutaneous injection of olive oil daily while the other groups got 3 mg/kg/daily of testosterone propionate (TP) subcutaneously plus 50 mg/kg/daily of AgNPs intraperitoneally (B), 3 mg/kg/daily of TP plus 25 mg/kg/daily of AgNPs (C), 3 mg/kg/daily of TP only (D) and 25 mg/kg/daily of AgNPs only (E). The animals were sacrificed after 14 days, and the prostate gland, liver, and kidney were processed for histological analysis. Phytochemical screening and GC-MS analysis were performed to determine the composition of the M oleifera extract used. Biogenic AgNPs with an average diameter of 23 nm were synthesized. Biogenic AgNPs ameliorated hormone-induced prostate enlargement, and the inhibition of prostatic hypertrophy could be due to the presence of a significant amount of plant fatty acids and phytosterols in the aqueous extract of M oleifera extract. However, the administration of biogenic AgNPs at higher doses impacted negatively on the cytoarchitecture of the liver. Green synthesis of AgNPs with the aqueous extract of Moringa oleifera might be beneficial for the treatment of BPH.Keywords: benign prostatic hyperplasia, biogenic synthesis, Moringa oleifera, silver nanoparticles, testosterone
Procedia PDF Downloads 934114 Effect of Information and Communication Technology (ICT) Usage by Cassava Farmers in Otukpo Local Government Area of Benue State, Nigeria
Authors: O. J. Ajayi, J. H. Tsado, F. Olah
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The study analyzed the effect of information and communication technology (ICT) usage on cassava farmers in Otukpo local government area of Benue state, Nigeria. Primary data was collected from 120 randomly selected cassava farmers using multi-stage sampling technique. A structured questionnaire and interview schedule was employed to generate data. Data were analyzed using descriptive (frequency, mean and percentage) and inferential statistics (OLS (ordinary least square) and Chi-square). The result revealed that majority (78.3%) were within the age range of 21-50 years implying that the respondents were within the active age for maximum production. 96.8% of the respondents had one form of formal education or the other. The sources of ICT facilities readily available in area were radio(84.2%), television(64.2%) and mobile phone(90.8%) with the latter being the most relied upon for cassava farming. Most of the farmers were aware (98.3%) and had access (95.8%) to these ICT facilities. The dependence on mobile phone and radio were highly relevant in cassava stem selection, land selection, land preparation, cassava planting technique, fertilizer application and pest and disease management. The value of coefficient of determination (R2) indicated an 89.1% variation in the output of cassava farmers explained by the inputs indicated in the regression model implying that, there is a positive and significant relationship between the inputs and output. The results also indicated that labour, fertilizer and farm size were significant at 1% level of probability while ICT use was significant at 10%. Further findings showed that finance (78.3%) was the major constraint associated with ICT use. Recommendations were made on strengthening the use of ICT especially contemporary ones like the computer and internet among farmers for easy information sourcing which can boost agricultural production, improve livelihood and subsequently food security. This may be achieved by providing credit or subsidies and information centres like telecentres and cyber cafes through government assistance or partnership.Keywords: ICT, cassava farmers, inputs, output
Procedia PDF Downloads 3094113 We Are Thriving: Increasing the Number of Women in Engineering
Authors: Kathryn Redmond, Mojdeh Asadollahi Pajouh, Grace Panther, Rick Evans, Stacey Kulesza, Jia Liang
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An on-going focus in engineering education research is on increasing the number of women in engineering. While the number of women participating in engineering project teams has increased over the past five years, the number of women enrolled in engineering colleges remains stagnant. Previous studies have explored why the number of women enrolled in engineering colleges remains small. In doing so, researchers focused primarily on negative experiences women encountered. Instead of looking at negative experiences, which can further deter women from entering the field, the aim of this study is to explore the personal and institutional factors that allow women to succeed and thrive in undergraduate engineering programs. There are two research questions addressed in this paper. The first is: what are the personal traits and characteristics that allow women to thrive in engineering? The other is: what are the institutional policies and culture, as well as micro-level behaviors on project teams, that influence the environment for women to thrive in engineering? Two women studying engineering at an R1 university were interviewed. Each woman was interviewed three times for a total of six interviews. The phenomenographic interviews focused on the lived experiences of the participants to better understand thriving in engineering. The first interview focused on the women’s personal life and background, the second on their learning journey and project team experiences, and the third focused on videos the women took through a method called Photovoice. Interviews were transcribed, and an inductive thematic analysis was conducted. Four themes were identified. Multiple coders were utilized to ensure trustworthiness and increase interrater reliability. Results indicate that thriving women have supportive families, experienced gender biases, and enjoy hands-on engineering and creating a final product. These traits and experiences may help inspire younger women to pursue engineering degrees and can help inform institutions as they make policy changes to support women. Additional women will be recruited from four different universities to further develop a theoretical framework to help inform institutions in how they can support women to thrive in engineering.Keywords: diversity, inclusion, project teams, women in engineering
Procedia PDF Downloads 1084112 Quality of Bali Beef and Broiler after Immersion in Liquid Smoke on Different Concentrations and Storage Times
Authors: E. Abustam, M. Yusuf, H. M. Ali, M. I. Said, F. N. Yuliati
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The aim of this study was to improve the durability and quality of Bali beef (M. Longissimus dorsi) and broiler carcass through the addition of liquid smoke as a natural preservative. This study was using Longissimus dorsi muscle from male Bali beef aged 3 years, broiler breast and thigh aged 40 days. Three types of meat were marinated in liquid smoke with concentrations of 0, 5, and 10% for 30 minutes at the level of 20% of the sample weight (w/w). The samples were storage at 2-5°C for 1 month. This study designed as a factorial experiment 3 x 3 x 4 based on a completely randomized design with 5 replications; the first factor was meat type (beef, chicken breast and chicken thigh); the 2nd factor was liquid smoke concentrations (0, 5, and 10%), and the 3rd factor was storage duration (1, 2, 3, and 4 weeks). Parameters measured were TBA value, total bacterial colonies, water holding capacity (WHC), shear force value both before and after cooking (80°C – 15min.), and cooking loss. The results showed that the type of meat produced WHC, shear force value, cooking loss and TBA differed between the three types of meat. Higher concentration of liquid smoke, the WHC, shear force value, TBA, and total bacterial colonies were decreased; at a concentration of 10% of liquid smoke, the total bacterial colonies decreased by 57.3% from untreated with liquid smoke. Longer storage, the total bacterial colonies and WHC were increased, while the shear force value and cooking loss were decreased. It can be concluded that a 10% concentration of liquid smoke was able to maintain fat oxidation and bacterial growth in Bali beef and chicken breast and thigh.Keywords: Bali beef, chicken meat, liquid smoke, meat quality
Procedia PDF Downloads 3904111 Problems and Prospects of Agricultural Biotechnology in Nigeria’s Developing Economy
Authors: Samson Abayomi Olasoju, Olufemi Adekunle, Titilope Edun, Johnson Owoseni
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Science offers opportunities for revolutionizing human activities, enriched by input from scientific research and technology. Biotechnology is a major force for development in developing countries such as Nigeria. It is found to contribute to solving human problems like water and food insecurity that impede national development and threaten peace wherever it is applied. This review identified the problems of agricultural biotechnology in Nigeria. On the part of rural farmers, there is a lack of adequate knowledge or awareness of biotechnology despite the fact that they constitute the bulk of Nigerian farmers. On part of the government, the problems include: lack of adequate implementation of government policy on bio-safety and genetically modified products, inadequate funding of education as well as research and development of products related to biotechnology. Other problems include: inadequate infrastructures (including laboratory), poor funding and lack of national strategies needed for development and running of agricultural biotechnology. In spite of all the challenges associated with agricultural biotechnology, its prospects still remain great if Nigeria is to meet with the food needs of the country’s ever increasing population. The introduction of genetically engineered products will lead to the high productivity needed for commercialization and food security. Insect, virus and other related diseases resistant crops and livestock are another viable area of contribution of biotechnology to agricultural production. In conclusion, agricultural biotechnology will not only ensure food security, but, in addition, will ensure that the local farmers utilize appropriate technology needed for large production, leading to the prosperity of the farmers and national economic growth, provided government plays its role of adequate funding and good policy implementation.Keywords: biosafety, biotechnology, food security, genetic engineering, genetic modification
Procedia PDF Downloads 1734110 A Comparative Study: Influences of Polymerization Temperature on Phosphoric Acid Doped Polybenzimidazole Membranes
Authors: Cagla Gul Guldiken, Levent Akyalcin, Hasan Ferdi Gercel
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Fuel cells are electrochemical devices which convert the chemical energy of hydrogen into the electricity. Among the types of fuel cells, polymer electrolyte membrane fuel cells (PEMFCs) are attracting considerable attention as non-polluting power generators with high energy conversion efficiencies in mobile applications. Polymer electrolyte membrane (PEM) is one of the essential components of PEMFCs. Perfluorosulfonic acid based membranes known as Nafion® is widely used as PEMs. Nafion® membranes water dependent proton conductivity which limits the operating temperature below 100ᵒC. At higher temperatures, proton conductivity and mechanical stability of these membranes decrease because of dehydration. Polybenzimidazole (PBI), which has good anhydrous proton conductivity after doped with acids, as well as excellent thermal stability, shows great potential in the application of high temperature PEMFCs. In the present study, PBI polymers were synthesized by solution polycondensation at 190 and 210ᵒC. The synthesized polymers were characterized by FTIR, 1H NMR, and TGA. Phosphoric acid doped PBI membranes were prepared and tested in a PEMFC. The influences of reaction temperature on structural properties of synthesized polymers were investigated. Mechanical properties, acid-doping level, proton conductivity, and fuel cell performances of prepared phosphoric acid doped PBI membranes were evaluated. The maximum power density was found as 32.5 mW/cm² at 120ᵒC.Keywords: fuel cell, high temperature polymer electrolyte membrane, polybenzimidazole, proton exchange membrane fuel cell
Procedia PDF Downloads 1834109 Body Mass Components in Young Soccer Players
Authors: Elizabeta Sivevska, Sunchica Petrovska, Vaska Antevska, Lidija Todorovska, Sanja Manchevska, Beti Dejanova, Ivanka Karagjozova, Jasmina Pluncevic Gligoroska
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Introduction: Body composition plays an important role in the selection of young soccer players and it is associated with their successful performance. The most commonly used model of body composition divides the body into two compartments: fat components and fat-free mass (muscular and bone components). The aims of the study were to determine the body composition parameters of young male soccer players and to show the differences in age groups. Material and methods: A sample of 52 young male soccer players, with an age span from 9 to 14 years were divided into two groups according to the age (group 1 aged 9 to 12 years and group 2 aged 12 to 14 years). Anthropometric measurements were taken according to the method of Mateigka. The following measurements were made: body weight, body height, circumferences (arm, forearm, thigh and calf), diameters (elbow, knee, wrist, ankle) and skinfold thickness (biceps, triceps, thigh, leg, chest, abdomen). The measurements were used in Mateigka’s equations. Results: Body mass components were analyzed as absolute values (in kilograms) and as percentage values: the muscular component (MC kg and MC%), the bone component (BCkg and BC%) and the body fat (BFkg and BF%). The group up to 12 years showed the following mean values of the analyzed parameters: MM=21.5kg; MM%=46.3%; BC=8.1kg; BC%=19.1%; BF= 6.3kg; BF%= 15.7%. The second group aged 12-14 year had mean values of body composition parameters as follows: MM=25.6 kg; MM%=48.2%; BC = 11.4 kg; BC%=21.6%; BF= 8.5 kg; BF%= 14. 7%. Conclusions: The young soccer players aged 12 up to 14 years who are in the pre-pubertal phase of growth and development had higher bone component (p<0.05) compared to younger players. There is no significant difference in muscular and fat body component between the two groups of young soccer players.Keywords: body composition, young soccer players, body fat, fat-free mass
Procedia PDF Downloads 4574108 Effect of Food Supplies Holstein Calves Supplemented with Bacillus Subtilis PB6 in Morbidity and Mortality
Authors: Banca Patricia Pena Revuelta, Ramiro Gonzalez Avalos, Juan Leonardo Rocha Valdez, Jose Gonzalez Avalos, Karla Rodriguez Hernandez
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Probiotics are a promising alternative to improve productivity and animals' health. In addition, they can be part of the composition of different types of products, including foods (functional foods), medicines, and dietary supplements. The objective of the present work was to evaluate the effect of the feeding of Holstein calves supplemented with bacillus subtilis PB6 in morbidity and mortality. 60 newborn animals were used, randomly included in 1 of 3 treatments. The treatments were as follows: T1 = control, T2 = 10 g / calf / day. The first takes within 20 min after birth, T3 = 10 g / calf/day. The first takes between 12 and 24 h after birth. In all the treatments, 432 L of pasteurized whole milk divided into two doses/day 07:00 and 15:00, respectively, were given for 60 days. The addition of bacillus subtilis PB6 was carried out in the milk tub at the time of feeding them. The first colostrum intake (2 L • intake) was given within 2 h after birth, after which they were given a second 6 h after the first one. The diseases registered to monitor the morbidity and mortality of the calves were: diarrhea and pneumonia. The registry was carried out from birth to 60 days of life. The parameter evaluated was food consumption. The variable statistical analysis was performed using analysis of variance, and comparison of means was performed using the Tukey test. The value of P < 0.05 was used to consider the statistical difference. The results of the present study in relation to the consumption of food show no statistical difference P < 0.05 between treatments (14,762, 11,698, and 12,403 kg of food average, respectively). Calves group to which they were not provided Bacillus subtilis PB6 obtained higher feed intake. The addition of Bacillus subtilis PB6 in feeding calves does not increase feed intake.Keywords: feeding, development, milk, probiotic
Procedia PDF Downloads 1454107 Representational Conference Profile of Secondary Students in Understanding Selected Chemical Principles
Authors: Ryan Villafuerte Lansangan
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Assessing students’ understanding in the microscopic level of an abstract subject like chemistry poses a challenge to teachers. Literature reveals that the use of representations serves as an essential avenue of measuring the extent of understanding in the discipline as an alternative to traditional assessment methods. This undertaking explored the representational competence profile of high school students from the University of Santo Tomas High School in understanding selected chemical principles and correlate this with their academic profile in chemistry based on their performance in the academic achievement examination in chemistry administered by the Center for Education Measurement (CEM). The common misconceptions of the students on the selected chemistry principles based on their representations were taken into consideration as well as the students’ views regarding their understanding of the role of chemical representations in their learning. The students’ level of representation task instrument consisting of the main lessons in chemistry with a corresponding scoring guide was prepared and utilized in the study. The study revealed that most of the students under study are unanimously rated as Level 2 (symbolic level) in terms of their representational competence in understanding the selected chemical principles through the use of chemical representations. Alternative misrepresentations were most observed on the students’ representations on chemical bonding concepts while the concept of chemical equation appeared to be the most comprehensible topic in chemistry for the students. Data implies that teachers’ representations play an important role in helping the student understand the concept in a microscopic level. Results also showed that the academic achievement in the chemistry of the students based on the standardized CEM examination has a significant association with the students’ representational competence. In addition, the students’ responses on the students’ views in chemical representations questionnaire evidently showed a good understanding of what a chemical representation or a mental model is by drawing a negative response that these tools should be an exact replica. Moreover, the students confirmed a greater appreciation that chemical representations are explanatory tools.Keywords: chemical representations, representational competence, academic profile in chemistry, secondary students
Procedia PDF Downloads 4044106 Strengthening Regulation and Supervision of Microfinance Sector for Development in Ethiopia
Authors: Megersa Dugasa Fite
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This paper analyses regulatory and supervisory issues in the Ethiopian micro finance sector, which caters to the needs of those who have been excluded from the formal financial sector. Micro-finance has received increased importance in development because of its grand goal to give credits to the poor to raise their economic and social well-being and improve the quality of lives. The micro-finance at present has been moving towards a credit-plus period through covering savings and insurance functions. It thus helps in reducing the rate of financial exclusion and social segregation, alleviating poverty and, consequently, stimulating development. The Ethiopian micro finance policy has been generally positive and developmental but major regulatory and supervisory limitations such as the absolute prohibition of NGOs to participate in micro credit functions, higher risks for depositors of micro-finance institutions, lack of credit information services with research and development, the unmet demand, and risks of market failures due to over-regulation are disappointing. Therefore, to remove the limited reach and high degree of problems typical in the informal means of financial intermediation plus to deal with the failure of formal banks to provide basic financial services to a significant portion of the country’s population, more needs to be done on micro finance. Certain key regulatory and supervisory revisions hence need to be taken to strengthen the Ethiopian micro finance sector so that it can practically provide majority poor access to a range of high quality financial services that help them work their way out of poverty and the incapacity it imposes.Keywords: micro-finance, micro-finance regulation and supervision, micro-finance institutions, financial access, social segregation, poverty alleviation, development, Ethiopia
Procedia PDF Downloads 3934105 Self-Reported Health Status and Its Consistency: Evidence from India
Authors: Dona Ghosh, Zakir Husain
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In India, the increase in share of aged has generated many social and economic issues, of which health concerns is a major challenge that society must confront in coming years. Self-reported health (SRH) is a popular health measure in this regard but has been questioned in recent years due to its heavy dependence on the socioeconomic status. So, the validity of SRH, as a measure of health status during old age, is needed to be verified. This paper emphasizes on the self-reported health and related inconsistent responses among elderly in India. The objective of the study is bifurcated into two parts: firstly, to identify the socioeconomic determinants of subjective health status and its change over time; and secondly, to analyse the role of the socioeconomic components in providing inconsistent responses regarding the health status of elderly. Inconsistency in response can rise in two ways: positive response bias (if an individual has a health problem but reports his/her health as good) and negative response bias (if bad health is reported even if there is no health problem). However, in the present study, we focus only on the negative response bias of elderly individuals. To measure the inconsistencies in responses, self-reported health is compared with two types of physical health conditions – existence of chronicle ailment and physical immobility. Using NSS dataset of 60th and 71st rounds, the study found that subjective health has worsened over time in both rural and urban areas. Findings suggest that inconsistency in responses, related to chronic ailment, vary across social classes, living environments, geographical regions, age groups and education levels. On the contrary, variation in inconsistent responses regarding physical mobility is quite rare and difficult to explain by socioeconomic characteristics because most of the indicators are found to be insignificant in this regard. The findings indicate that in case of chronicle ailment, inconsistency between objective and subjective health status largely depends on socioeconomic conditions but the importance of such factors disappears for physical immobility.Keywords: India, aging, self-reported health, inconsistent responses
Procedia PDF Downloads 2904104 Efficacy of Clickers in L2 Interaction
Authors: Ryoo Hye Jin Agnes
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This study aims to investigate the efficacy of clickers in fostering L2 class interaction. In an L2 classroom, active learner-to-learner interactions and learner-to-teacher interactions play an important role in language acquisition. In light of this, introducing learning tools that promote such interactions would benefit L2 classroom by fostering interaction. This is because the anonymity of clickers allows learners to express their needs without the social risks associated with speaking up in the class. clickers therefore efficiently help learners express their level of understanding during the process of learning itself. This allows for an evaluative feedback loop where both learners and teachers understand the level of progress of the learners, better enabling classrooms to adapt to the learners’ needs. Eventually this tool promotes participation from learners. This, in turn, is believed to be effective in fostering classroom interaction, allowing learning to take place in a more comfortable yet vibrant way. This study is finalized by presenting the result of an experiment conducted to verify the effectiveness of this approach when teaching pragmatic aspect of Korean expressions with similar semantic functions. The learning achievement of learners in the experimental group was found higher than the learners’ in a control group. A survey was distributed to the learners, questioning them regarding the efficacy of clickers, and how it contributed to their learning in areas such as motivation, self-assessment, increasing participation, as well as giving feedback to teachers. Analyzing the data collected from the questionnaire given to the learners, the study presented data suggesting that this approach increased the scope of interactivity in the classroom, thus not only increasing participation but enhancing the type of classroom participation among learners. This participation in turn led to a marked improvement in their communicative abilities.Keywords: second language acquisition, interaction, clickers, learner response system, output from learners, learner’s cognitive process
Procedia PDF Downloads 5194103 Canine Neonatal Mortality at the São Paulo State University Veterinary Hospital, Botucatu, São Paulo, Brazil – Preliminary Data
Authors: Maria L. G. Lourenço, Keylla H. N. P. Pereira, Viviane Y. Hibaru, Fabiana F. Souza, João C. P. Ferreira, Simone B. Chiacchio, Luiz H. A. Machado
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The neonatal mortality rates in dogs are considered high, varying between 5.7 and 21.2% around the world, and the causes of the deaths are often unknown. Data regarding canine neonatal mortality are scarce in Brazil. This study aims at describing the neonatal mortality rates in dogs, as well as the main causes of death. The study included 152 litters and 669 neonates admitted to the São Paulo State University (UNESP) Veterinary Hospital, Botucatu, São Paulo, Brazil between January 2018 and September 2019. The overall mortality rate was 16.7% (112/669), with 40% (61/152) of the litters presenting at least one case of stillbirth or neonatal mortality. The rate of stillbirths was 7.7% (51/669), while the neonatal mortality rate was 9% (61/669). The early mortality rate (0 to 2 days) was 13.7% (92/669), accounting for 82.1% (92/112) of all deaths. The late mortality rate (3 to 30 days) was 2.7% (18/669), accounting for 16% (18/112) of all deaths. Infection was the causa mortis in 51.8% (58/112) of the newborns, of which 30.3% (34/112) were caused by bacterial sepsis, and 21.4% (24/112) were caused by other bacterial, viral or parasite infections. Other causes of death included congenital malformations (15.2%, 17/112), of which 5.3% (6/112) happened through euthanasia due to malformations incompatible with life; asphyxia/hypoxia by dystocia (9.8%, 11/112); wasting syndrome in debilitated newborns (6.2%, 7/112); aspiration pneumonia (3.6%, 4/112); agalactia (2.7%, 3/112); trauma (1.8%, 2/112); administration of contraceptives to the mother (1.8%, 2/112) and unknown causes (7.1%, 8/112). The neonatal mortality rate was considered high, but they may be even higher in locations without adequate care for the mothers and neonates. Therefore, prenatal examinations and early neonatal care are of utmost importance for the survival of these patients.Keywords: neonate dogs, puppies, mortality rate, neonatal death
Procedia PDF Downloads 2014102 Effect of Built in Polarization on Thermal Properties of InGaN/GaN Heterostructures
Authors: Bijay Kumar Sahoo
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An important feature of InₓGa₁-ₓN/GaN heterostructures is strong built-in polarization (BIP) electric field at the hetero-interface due to spontaneous (sp) and piezoelectric (pz) polarizations. The intensity of this electric field reaches several MV/cm. This field has profound impact on optical, electrical and thermal properties. In this work, the effect of BIP field on thermal conductivity of InₓGa₁-ₓN/GaN heterostructure has been investigated theoretically. The interaction between the elastic strain and built in electric field induces additional electric polarization. This additional polarization contributes to the elastic constant of InₓGa₁-ₓN alloy. This in turn modifies material parameters of InₓGa₁-ₓN. The BIP mechanism enhances elastic constant, phonon velocity and Debye temperature and their bowing constants in InₓGa₁-ₓN alloy. These enhanced thermal parameters increase phonon mean free path which boost thermal conduction process. The thermal conductivity (k) of InxGa1-xN alloy has been estimated for x=0, 0.1, 0.3 and 0.9. Computation finds that irrespective of In content, the room temperature k of InₓGa₁-ₓN/GaN heterostructure is enhanced by BIP mechanism. Our analysis shows that at a certain temperature both k with and without BIP show crossover. Below this temperature k with BIP field is lower than k without BIP; however, above this temperature k with BIP field is significantly contributed by BIP mechanism leading to k with BIP field become higher than k without BIP field. The crossover temperature is primary pyroelectric transition temperature. The pyroelectric transition temperature of InₓGa₁-ₓN alloy has been predicted for different x. This signature of pyroelectric nature suggests that thermal conductivity can reveal pyroelectricity in InₓGa₁-ₓN alloy. The composition dependent room temperature k for x=0.1 and 0.3 are in line with prior experimental studies. The result can be used to minimize the self-heating effect in InₓGa₁-ₓN/GaN heterostructures.Keywords: built-in polarization, phonon relaxation time, thermal properties of InₓGa₁-ₓN /GaN heterostructure, self-heating
Procedia PDF Downloads 4074101 Process Parameter Study on Friction Push Plug Welding of AA6061 Alloy
Authors: H. Li, W. Qin, Ben Ye
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Friction Push Plug Welding (FPPW) is a solid phase welding suitable for repairing defective welds and filling self-reacting weld keyholes in Friction Stir Welds. In FPPW process, a tapered shaped plug is rotated at high speed and forced into a tapered hole in the substrate. The plug and substrate metal is softened by the increasing temperature generated by friction and material plastic deformation. This paper aims to investigate the effect of process parameters on the quality of the weld. Orthogonal design methods were employed to reduce the amount of experiment. Three values were selected for each process parameter, rotation speed (1500r/min, 2000r/min, 2500r/min), plunge depth (2mm, 3mm, 4mm) and plunge speed (60mm/min, 90mm/min, 120r/min). AA6061aluminum alloy plug and substrate plate was used in the experiment. In a trial test with the plunge depth of 1mm, a noticeable defect appeared due to the short plunge time and insufficient temperature. From the recorded temperature profiles, it was found that the peak temperature increased with the increase of the rotation speed, plunge speed and plunge depth. In the initial stage, the plunge speed was the main factor affecting heat generation, while in the steady state welding stage, the rotation speed played a more important role. The FPPW weld defect includes flash and incomplete penetration in the upper, middle and bottom interface with the substrate. To obtain defect free weld, the higher rotation speed and proper plunge depth were recommended.Keywords: friction push plug welding, process parameter, weld defect, orthogonal design
Procedia PDF Downloads 1454100 Effect of the Vertical Pressure on the Electrical Behaviour of the Micro-Copper Polyurethane Composite Films
Authors: Saeid Mehvari, Yolanda Sanchez-Vicente, Sergio González Sánchez, Khalid Lafdi
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Abstract- Materials with a combination of transparency, electrical conductivity, and flexibility are required in the growing electronic sector. In this research, electrically conductive and flexible films have been prepared. These composite films consist of dispersing micro-copper particles into polyurethane (PU) matrix. Two sets of samples were made using both spin coating technique (sample thickness lower than 30 μm) and materials casting (sample thickness lower than 100 μm). Copper concentrations in the PU matrix varied from 0.5 to 20% by volume. The dispersion of micro-copper particles into polyurethane (PU) matrix were characterised using optical microscope and scanning electron microscope. The electrical conductivity measurement was carried out using home-made multimeter set up under pressures from 1 to 20 kPa through thickness and in plane direction. It seems that samples made by casting were not conductive. However, the sample made by spin coating shows through-thickness conductivity when they are under pressure. The results showed that spin-coated films with higher concentration of 2 vol. % of copper displayed a significant increase in the conductivity value, known as percolation threshold. The maximum conductivity of 7.2 × 10-1 S∙m-1 was reached at concentrations of filler with 20 vol. % at 20kPa. A semi-empirical model with adjustable coefficients was used to fit and predict the electrical behaviour of composites. For the first time, the finite element method based on the representative volume element (FE-RVE) was successfully used to predict their electrical behaviour under applied pressures. Keywords: electrical conductivity, micro copper, numerical simulation, percolation threshold, polyurethane, RVE model
Procedia PDF Downloads 1944099 Harmonic Assessment and Mitigation in Medical Diagonesis Equipment
Authors: S. S. Adamu, H. S. Muhammad, D. S. Shuaibu
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Poor power quality in electrical power systems can lead to medical equipment at healthcare centres to malfunction and present wrong medical diagnosis. Equipment such as X-rays, computerized axial tomography, etc. can pollute the system due to their high level of harmonics production, which may cause a number of undesirable effects like heating, equipment damages and electromagnetic interferences. The conventional approach of mitigation uses passive inductor/capacitor (LC) filters, which has some drawbacks such as, large sizes, resonance problems and fixed compensation behaviours. The current trends of solutions generally employ active power filters using suitable control algorithms. This work focuses on assessing the level of Total Harmonic Distortion (THD) on medical facilities and various ways of mitigation, using radiology unit of an existing hospital as a case study. The measurement of the harmonics is conducted with a power quality analyzer at the point of common coupling (PCC). The levels of measured THD are found to be higher than the IEEE 519-1992 standard limits. The system is then modelled as a harmonic current source using MATLAB/SIMULINK. To mitigate the unwanted harmonic currents a shunt active filter is developed using synchronous detection algorithm to extract the fundamental component of the source currents. Fuzzy logic controller is then developed to control the filter. The THD without the active power filter are validated using the measured values. The THD with the developed filter show that the harmonics are now within the recommended limits.Keywords: power quality, total harmonics distortion, shunt active filters, fuzzy logic
Procedia PDF Downloads 4774098 The Development of a Nanofiber Membrane for Outdoor and Activity Related Purposes
Authors: Roman Knizek, Denisa Knizkova
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This paper describes the development of a nanofiber membrane for sport and outdoor use at the Technical University of Liberec (TUL) and the following cooperation with a private Czech company which launched this product onto the market. For making this membrane, Polyurethan was electrospun on the Nanospider spinning machine, and a wire string electrode was used. The created nanofiber membrane with a nanofiber diameter of 150 nm was subsequently hydrophobisied using a low vacuum plasma and Fluorocarbon monomer C6 type. After this hydrophobic treatment, the nanofiber membrane contact angle was higher than 125o, and its oleophobicity was 6. The last step was a lamination of this nanofiber membrane with a woven or knitted fabric to create a 3-layer laminate. Gravure printing technology and polyurethane hot-melt adhesive were used. The gravure roller has a mesh of 17. The resulting 3-layer laminate has a water vapor permeability Ret of 1.6 [Pa.m2.W-1] (– measured in compliance with ISO 11092), it is 100% windproof (– measured in compliance with ISO 9237), and the water column is above 10 000 mm (– measured in compliance with ISO 20811). This nanofiber membrane which was developed in the laboratories of the Technical University of Liberec was then produced industrially by a private company. A low vacuum plasma line and a lamination line were needed for industrial production, and the process had to be fine-tuned to achieve the same parameters as those achieved in the TUL laboratories. The result of this work is a newly developed nanofiber membrane which offers much better properties, especially water vapor permeability, than other competitive membranes. It is an example of product development and the consequent fine-tuning for industrial production; it is also an example of the cooperation between a Czech state university and a private company.Keywords: nanofiber membrane, start-up, state university, private company, product
Procedia PDF Downloads 1394097 Potential Use of Leaching Gravel as a Raw Material in the Preparation of Geo Polymeric Material as an Alternative to Conventional Cement Materials
Authors: Arturo Reyes Roman, Daniza Castillo Godoy, Francisca Balarezo Olivares, Francisco Arriagada Castro, Miguel Maulen Tapia
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Mining waste–based geopolymers are a sustainable alternative to conventional cement materials due to their contribution to the valorization of mining wastes as well as to the new construction materials with reduced fingerprints. The objective of this study was to determine the potential of leaching gravel (LG) from hydrometallurgical copper processing to be used as a raw material in the manufacture of geopolymer. NaOH, Na2SiO3 (modulus 1.5), and LG were mixed and then wetted with an appropriate amount of tap water, then stirred until a homogenous paste was obtained. A liquid/solid ratio of 0.3 was used for preparing mixtures. The paste was then cast in cubic moulds of 50 mm for the determination of compressive strengths. The samples were left to dry for 24h at room temperature, then unmoulded before analysis after 28 days of curing time. The compressive test was conducted in a compression machine (15/300 kN). According to the laser diffraction spectroscopy (LDS) analysis, 90% of LG particles were below 500 μm. The X-ray diffraction (XRD) analysis identified crystalline phases of albite (30 %), Quartz (16%), Anorthite (16 %), and Phillipsite (14%). The X-ray fluorescence (XRF) determinations showed mainly 55% of SiO2, 13 % of Al2O3, and 9% of CaO. ICP (OES) concentrations of Fe, Ca, Cu, Al, As, V, Zn, Mo, and Ni were 49.545; 24.735; 6.172; 14.152, 239,5; 129,6; 41,1;15,1, and 13,1 mg kg-1, respectively. The geopolymer samples showed resistance ranging between 2 and 10 MPa. In comparison with the raw material composition, the amorphous percentage of materials in the geopolymer was 35 %, whereas the crystalline percentage of main mineral phases decreased. Further studies are needed to find the optimal combinations of materials to produce a more resistant and environmentally safe geopolymer. Particularly are necessary compressive resistance higher than 15 MPa are necessary to be used as construction unit such as bricks.Keywords: mining waste, geopolymer, construction material, alkaline activation
Procedia PDF Downloads 934096 Metagovernance and Sustainable Development Goals: Importance of Sustainable Policies and Democratic Institutions
Authors: Ghulam Rasool Madni
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Global economies are prioritizing the attainment of Sustainable Development Goals (SDGs) for well-being of their people. An emphasis lies on the concept of metagovernance when contemplating the role of government in SDGs, especially in the context of its influence and guidance. Existing literature acknowledges the pivotal role of metagovernance in achieving the SDGs, but aspects of metagovernance unclear that are important for 17 SDGs. Using data from 41 countries, a comparative analysis is conducted for the year 2022. Utilizing a multiple regression analysis, the impact of different dimensions of metagovernance to achieve SDGs is explored, with a particular focus on sustainable policies, strategic capacity, policy coherence, democratic institutions, reflexivity, and adaptation. It is found that sustainable policies have a positive and significant relationship with different SDGs, including no poverty, zero hunger, health, sanitation and clean water, affordable and clean energy, decent work and economic growth, industry, innovation and infrastructure, reduced inequalities while democratic institutions also have a positive relationship with no poverty, good health and well-being, quality education, gender equality, clean water and sanitation, clean and affordable energy, and peace, justice, and strong institutions in these countries. Policymakers are suggested to ensure that sustainable policies are backed by legislation to provide them with a strong legal foundation. It is suggested to develop a long-term vision for sustainability that goes beyond short-term political cycles. Economies are encouraged to invest in building the capacity of government agencies, civil society organizations, and other stakeholders to effectively implement sustainable policies. Moreover, democratic institutions may be established through a constitution providing a solid foundation for democratic governance, including protection of human rights, separation of powers, and mechanisms for accountability and transparency.Keywords: metagovernance, sustainable development goals, sustainable policies, democratic institutions
Procedia PDF Downloads 184095 Effects of Nitrogen Addition on Litter Decomposition and Nutrient Release in a Temperate Grassland in Northern China
Authors: Lili Yang, Jirui Gong, Qinpu Luo, Min Liu, Bo Yang, Zihe Zhang
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Anthropogenic activities have increased nitrogen (N) inputs to grassland ecosystems. Knowledge of the impact of N addition on litter decomposition is critical to understand ecosystem carbon cycling and their responses to global climate change. The aim of this study was to investigate the effects of N addition and litter types on litter decomposition of a semi-arid temperate grassland during growing and non-growing seasons in Inner Mongolia, northern China, and to identify the relation between litter decomposition and C: N: P stoichiometry in the litter-soil continuum. Six levels of N addition were conducted: CK, N1 (0 g Nm−2 yr−1), N2 (2 g Nm−2 yr−1), N3 (5 g Nm−2 yr−1), N4 (10 g Nm−2 yr−1) and N5 (25 g Nm−2 yr−1). Litter decomposition rates and nutrient release differed greatly among N addition gradients and litter types. N addition promoted litter decomposition of S. grandis, but exhibited no significant influence on L. chinensis litter, indicating that the S. grandis litter decomposition was more sensitive to N addition than L. chinensis. The critical threshold for N addition to promote mixed litter decomposition was 10 -25g Nm−2 yr−1. N addition altered the balance of C: N: P stoichiometry between litter, soil and microbial biomass. During decomposition progress, the L. chinensis litter N: P was higher in N2-N4 plots compared to CK, while the S. grandis litter C: N was lower in N3 and N4 plots, indicating that litter N or P content doesn’t satisfy microbial decomposers with the increasing of N addition. As a result, S. grandis litter exhibited net N immobilization, while L. chinensis litter net P immobilization. Mixed litter C: N: P stoichiometry satisfied the demand of microbial decomposers, showed net mineralization during the decomposition process. With the increasing N deposition in the future, mixed litter would potentially promote C and nutrient cycling in grassland ecosystem by increasing litter decomposition and nutrient release.Keywords: C: N: P stoichiometry, litter decomposition, nitrogen addition, nutrient release
Procedia PDF Downloads 4814094 Estimation Model for Concrete Slump Recovery by Using Superplasticizer
Authors: Chaiyakrit Raoupatham, Ram Hari Dhakal, Chalermchai Wanichlamlert
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This paper is aimed to introduce the solution of concrete slump recovery using chemical admixture type-F (superplasticizer, naphthalene base) to the practice, in order to solve unusable concrete problem due to concrete loss its slump, especially for those tropical countries that have faster slump loss rate. In the other hand, randomly adding superplasticizer into concrete can cause concrete to segregate. Therefore, this paper also develops the estimation model used to calculate amount of second dose of superplasticizer need for concrete slump recovery. Fresh properties of ordinary Portland cement concrete with volumetric ratio of paste to void between aggregate (paste content) of 1.1-1.3 with water-cement ratio zone of 0.30 to 0.67 and initial superplasticizer (naphthalene base) of 0.25%- 1.6% were tested for initial slump and slump loss for every 30 minutes for one and half hour by slump cone test. Those concretes with slump loss range from 10% to 90% were re-dosed and successfully recovered back to its initial slump. Slump after re-dosed was tested by slump cone test. From the result, it has been concluded that, slump loss was slower for those mix with high initial dose of superplasticizer due to addition of superplasticizer will disturb cement hydration. The required second dose of superplasticizer was affected by two major parameter, which were water-cement ratio and paste content, where lower water-cement ratio and paste content cause an increase in require second dose of superplasticizer. The amount of second dose of superplasticizer is higher as the solid content within the system is increase, solid can be either from cement particles or aggregate. The data was analyzed to form an equation use to estimate the amount of second dosage requirement of superplasticizer to recovery slump to its original.Keywords: estimation model, second superplasticizer dosage, slump loss, slump recovery
Procedia PDF Downloads 1984093 Revenue Management of Perishable Products Considering Freshness and Price Sensitive Customers
Authors: Onur Kaya, Halit Bayer
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Global grocery and supermarket sales are among the largest markets in the world and perishable products such as fresh produce, dairy and meat constitute the biggest section of these markets. Due to their deterioration over time, the demand for these products depends highly on their freshness. They become totally obsolete after a certain amount of time causing a high amount of wastage and decreases in grocery profits. In addition, customers are asking for higher product variety in perishable product categories, leading to less predictable demand per product and to more out-dating. Effective management of these perishable products is an important issue since it is observed that billions of dollars’ worth of food is expired and wasted every month. We consider coordinated inventory and pricing decisions for perishable products with a time and price dependent random demand function. We use stochastic dynamic programming to model this system for both periodically-reviewed and continuously-reviewed inventory systems and prove certain structural characteristics of the optimal solution. We prove that the optimal ordering decision scenario has a monotone structure and the optimal price value decreases by time. However, the optimal price changes in a non-monotonic structure with respect to inventory size. We also analyze the effect of 1 different parameters on the optimal solution through numerical experiments. In addition, we analyze simple-to-implement heuristics, investigate their effectiveness and extract managerial insights. This study gives valuable insights about the management of perishable products in order to decrease wastage and increase profits.Keywords: age-dependent demand, dynamic programming, perishable inventory, pricing
Procedia PDF Downloads 246