Search results for: free cash flows
1337 Forecasting Equity Premium Out-of-Sample with Sophisticated Regression Training Techniques
Authors: Jonathan Iworiso
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Forecasting the equity premium out-of-sample is a major concern to researchers in finance and emerging markets. The quest for a superior model that can forecast the equity premium with significant economic gains has resulted in several controversies on the choice of variables and suitable techniques among scholars. This research focuses mainly on the application of Regression Training (RT) techniques to forecast monthly equity premium out-of-sample recursively with an expanding window method. A broad category of sophisticated regression models involving model complexity was employed. The RT models include Ridge, Forward-Backward (FOBA) Ridge, Least Absolute Shrinkage and Selection Operator (LASSO), Relaxed LASSO, Elastic Net, and Least Angle Regression were trained and used to forecast the equity premium out-of-sample. In this study, the empirical investigation of the RT models demonstrates significant evidence of equity premium predictability both statistically and economically relative to the benchmark historical average, delivering significant utility gains. They seek to provide meaningful economic information on mean-variance portfolio investment for investors who are timing the market to earn future gains at minimal risk. Thus, the forecasting models appeared to guarantee an investor in a market setting who optimally reallocates a monthly portfolio between equities and risk-free treasury bills using equity premium forecasts at minimal risk.Keywords: regression training, out-of-sample forecasts, expanding window, statistical predictability, economic significance, utility gains
Procedia PDF Downloads 1071336 Biomass Energy: "The Boon for the Would"
Authors: Shubham Giri Goswami, Yogesh Tiwari
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In today’s developing world, India and other countries are developing different instruments and accessories for the better standard and life to be happy and prosper. But rather than this we human-beings have been using different energy sources accordingly, many persons such as scientist, researchers etc have developed many Energy sources like renewable and non-renewable energy sources. Like fossil fuel, coal, gas, petroleum products as non-renewable sources, and solar, wind energy as renewable energy source. Thus all non-renewable energy sources, these all Created pollution as in form of air, water etc. due to ultimate use of these sources by human the future became uncertain. Thus to minimize all this environmental affects and destroy the healthy environment we discovered a solution as renewable energy source. Renewable energy source in form of biomass energy, solar, wind etc. We found different techniques in biomass energy, that good energy source for people. The domestic waste, and is a good source of energy as daily extract from cow in form of dung and many other domestic products naturally can be used eco-friendly fertilizers. Moreover, as from my point of view the cow is able to extract 08-12 kg of dung which can be used to make wormy compost fertilizers. Furthermore, the calf urine as insecticides and use of such a compounds will lead to destroy insects and thus decrease communicable diseases. Therefore, can be used by every person and biomass energy can be in those areas such as rural areas where non-renewable energy sources cannot reach easily. Biomass can be used to develop fertilizers, cow-dung plants and other power generation techniques, and this energy is clean and pollution free and is available everywhere thus saves our beautiful planet or blue or life giving planet called as “EARTH”. We can use the biomass energy, which may be boon for the world in future.Keywords: biomass, energy, environment, human, pollution, renewable, solar energy, sources, wind
Procedia PDF Downloads 5261335 Design and Performance Evaluation of Plasma Spouted Bed Reactor for Converting Waste Plastic into Green Hydrogen
Authors: Palash Kumar Mollick, Leire Olazar, Laura Santamaria, Pablo Comendador, Gartzen Lopez, Martin Olazar
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Average calorific value of a mixure of waste plastic is approximately 38 MJ/kg. Present work aims to extract maximum possible energy from a mixure of waste plastic using a DC thermal plasma in a spouted bed reactor. Plasma pyrolysis and steam reforming process has shown a potential to generate hydrogen from plastic with much below of legal limit of producing dioxins and furans as the carcinogenic gases. A spouted bed pyrolysis rector can continuously process plastic beads to produce organic volatiles, which later react with steam in presence of catalyst to results in syngas. lasma being the fourth state of matter, can carry high impact electrons to favour the activation energy of any chemical reactions. Computational Fluid Dynamic (CFD) simulation using COMSOL Multiphysics software has been performed to evaluate performance of a plasma spouted bed reactor in producing contamination free hydrogen as a green energy from waste plastic beads. The simulation results will showcase a design of a plasma spouted bed reactor for converting plastic waste into green hydrogen in a single step process. The high temperature hydrodynamics of spouted bed with plastic beads and the corresponding temperature distribution inside the reaction chamber will be critically examined for it’s near future installation of demonstration plant.Keywords: green hydrogen, plastic waste, synthetic gas, pyrolysis, steam reforming, spouted bed, reactor design, plasma, dc palsma, cfd simulation
Procedia PDF Downloads 1141334 Lignin Valorization: Techno-Economic Analysis of Three Lignin Conversion Routes
Authors: Iris Vural Gursel, Andrea Ramirez
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Effective utilization of lignin is an important mean for developing economically profitable biorefineries. Current literature suggests that large amounts of lignin will become available in second generation biorefineries. New conversion technologies will, therefore, be needed to carry lignin transformation well beyond combustion to produce energy, but towards high-value products such as chemicals and transportation fuels. In recent years, significant progress on catalysis has been made to improve transformation of lignin, and new catalytic processes are emerging. In this work, a techno-economic assessment of two of these novel conversion routes and comparison with more established lignin pyrolysis route were made. The aim is to provide insights into the potential performance and potential hotspots in order to guide the experimental research and ease the commercialization by early identifying cost drivers, strengths, and challenges. The lignin conversion routes selected for detailed assessment were: (non-catalytic) lignin pyrolysis as the benchmark, direct hydrodeoxygenation (HDO) of lignin and hydrothermal lignin depolymerisation. Products generated were mixed oxygenated aromatic monomers (MOAMON), light organics, heavy organics, and char. For the technical assessment, a basis design followed by process modelling in Aspen was done using experimental yields. A design capacity of 200 kt/year lignin feed was chosen that is equivalent to a 1 Mt/y scale lignocellulosic biorefinery. The downstream equipment was modelled to achieve the separation of the product streams defined. For determining external utility requirement, heat integration was considered and when possible gasses were combusted to cover heating demand. The models made were used in generating necessary data on material and energy flows. Next, an economic assessment was carried out by estimating operating and capital costs. Return on investment (ROI) and payback period (PBP) were used as indicators. The results of the process modelling indicate that series of separation steps are required. The downstream processing was found especially demanding in the hydrothermal upgrading process due to the presence of significant amount of unconverted lignin (34%) and water. Also, external utility requirements were found to be high. Due to the complex separations, hydrothermal upgrading process showed the highest capital cost (50 M€ more than benchmark). Whereas operating costs were found the highest for the direct HDO process (20 M€/year more than benchmark) due to the use of hydrogen. Because of high yields to valuable heavy organics (32%) and MOAMON (24%), direct HDO process showed the highest ROI (12%) and the shortest PBP (5 years). This process is found feasible with a positive net present value. However, it is very sensitive to the prices used in the calculation. The assessments at this stage are associated with large uncertainties. Nevertheless, they are useful for comparing alternatives and identifying whether a certain process should be given further consideration. Among the three processes investigated here, the direct HDO process was seen to be the most promising.Keywords: biorefinery, economic assessment, lignin conversion, process design
Procedia PDF Downloads 2611333 Optimization Parameters Using Response Surface Method on Biomechanical Analysis for Malaysian Soccer Players
Authors: M. F. M. Ali, A. R. Ismail, B. M. Deros
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Soccer is very popular and ranked as the top sports in the world as well as in Malaysia. Although soccer sport in Malaysia is currently professionalized, but it’s plunging achievements within recent years continue and are not to be proud of. After review, the Malaysian soccer players are still weak in terms of kicking techniques. The instep kick is a technique, which is often used in soccer for the purpose of short passes and making a scoring. This study presents the 3D biomechanics analysis on a soccer player during performing instep kick. This study was conducted to determine the optimization value for approach angle, distance of supporting leg from the ball and ball internal pressure respect to the knee angular velocity of the ball on the kicking leg. Six subjects from different categories using dominant right leg and free from any injury were selected to take part in this study. Subjects were asked to perform one step instep kick according to the setting for the variables with different parameter. Data analysis was performed using 3 Dimensional “Qualisys Track Manager” system and will focused on the bottom of the body from the waist to the ankle. For this purpose, the marker will be attached to the bottom of the body before the kicking is perform by the subjects. Statistical analysis was conducted by using Minitab software using Response Surface Method through Box-Behnken design. The results of this study found the optimization values for all three parameters, namely the approach angle, 53.6º, distance of supporting leg from the ball, 8.84sm and ball internal pressure, 0.9bar with knee angular velocity, 779.27 degrees/sec have been produced.Keywords: biomechanics, instep kick, soccer, optimization
Procedia PDF Downloads 2301332 Theatrical Architecture in Bologna at the Beginning of the Twentieth Century: The Renaissance of Modernissimo Cinema
Authors: Giorgia Predari, Riccardo Gulli
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The paper describes the history and the stylistic choices adopted in the construction of Palazzo Ronzani in Bologna, which was the first building to rise after the heavy demolitions carried out in the historical center of the city at the beginning of the twentieth century. In 1910, the local administration adopted a detailed plan to change the aspect of the city, as it was already happening in the main European capitals. In this context, starting from 1911, the architect and scenographer Gualtiero Pontoni designed for Alessandro Ronzani -the owner of a well-known Bolognese beer company- his Palazzo, which is listed among the first multifunctional buildings in Bologna, containing offices, commercial activities, and entertainment spaces. In an area of about 2000 m², the architect was able to propose a theatre with a capacity of 2000 seats at the basement, shops, a cafè-chantant and a restaurant on the ground floor, clubs, studios and commercial stores on the mezzanine and the first plan, and a hotel on the upper floors. The whole core of the building, at the underground levels, consisted of a reinforced concrete frame (one of the first examples of this type of construction in the city), which allowed the hall to have a free span of 11 x 12 meters, and a height of about 9 meters. Used until 2007 as a cinema, the hall has remained then in disuse for almost 10 years, but now an important functional restoration project with a strong architectural and scenographic value is taking place. It will bring the spaces back to the original geometries, in a historical and artistic condition inspired by the styles of the early Twentieth century.Keywords: Modernissimo, Palazzo Ronzani, liberty, Bologna
Procedia PDF Downloads 1211331 Histopathological Effects of Trichodiniasis in Farmed Freshwater Rainbow Trout, Oncorhynchus mykiss, in West of Iran
Authors: Zahra Khoshnood, Reza Khoshnood
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The aim of present study was to monitor the presence of Trichodina sp. in Rainbow trout, Oncorhynchus mykiss collected from various fish farms in the western provinces of Iran during January, 2013- January, 2014. Out of 675 sampled fish 335, (49.16%) were infested with Trichodina. The highest prevalence was observed in the spring and winter followed by autumn and summer. In general, the intensity of infection was low except in cases where outbreaks of Trichodiniasis endangered the survival of fish in some ponds. In light infestation Trichodina is usually present on gills, fins and skin of apparently healthy fish. Clinical signs of Trichodiniasis only appear on fish with heavy infections and cases of moderate ones that are usually exposed to one or more stress factors including, rough handling during transportation from ponds, overcrowdness, malnutrition, high of free ammonia and low of oxygen concentration. Clinical signs of Trichodiniasis in sampled fish were sluggish movement, loss of appetite, black coloration, necrosis and ulcer on different parts of the body, detached scales and excessive accumulation of mucous in gill pouches. The most obvious histopathological changes in diseased fish were sloughing of the epidermal layer, aggregation of leucocytes and melanine-carrying cells (between the dermis and hypodermis) and proliferative changes including hyperplasia and hypertrophy of the epithelial lining cells of gill filaments which resulted in fusion of secondary lamellae. Control of Trichodiniasis, has been achieved by formalin bath treatment at a concentration of 250 ppm for one hour.Keywords: gill, histopathology, rainbow trout, Trichodina
Procedia PDF Downloads 4261330 Pregnant Women’s Views on a Trial of Posture for Fetal Malposition
Authors: Jennifer A. Barrowclough, Caroline A. Crowther, Bridget Kool
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Fetal malposition in labour is associated with adverse maternal and infant health outcomes. Evidence for effective interventions for fetal malposition is inconclusive. The feasibility and design of a randomized controlled trial (RCT) of maternal posture to improve maternal and infant outcomes of malposition should be considered, based on the hypothesis that gravity corrects malposition. The aim was to assess pregnant women’s views on the acceptability of a future trial of maternal posture for fetal malposition in labour, and the enablers and barriers of participation. Method: An online anonymous survey of pregnant women was conducted in Auckland during 2020. Descriptive summaries of quantitative data used chi-square to assess differences in proportions. The influence of maternal characteristics on women’s responses was assessed using cross-tabulation. Free text responses were analysed thematically. Results: Respondents (n=206) were mostly aged26-35 years (75%), of 29-38 weeks gestation (71%), of European (40%) or Asian (36%) ethnicity, were evenly nulliparous or multiparous. Most women (76%) had heard of fetal malposition in labour however only 28% were aware of the use of maternal posture to correct this. Most women (86%) were interested in labour research. Although 37% indicated they would participate in a future RCT of posture for fetal malposition, nearly half (47%) were unsure and a further quarter (15%) indicated they would not participate. Comfort was the predominant concern (22%). Almost half of the respondents (49%) indicated they would consult their partner before deciding on participation in an RCT. Conclusions: Participation in a trial of maternal posture in labour can be enabled through measures to enhance maternal comfort, increased awareness of malposition and the role of posture, and the involvement of partners during trial counselling and recruitment.Keywords: pregnant women, labour, presentation, posture, randomized controlled trial, survey
Procedia PDF Downloads 1631329 Magnetic Silica Nanoparticles as Viable Support for the Immobilization of Oxidative Enzymes
Authors: Y. Moldes-Diz, M. Gamallo, G. Eibes, C. Vazquez-Vazquez, G. Feijoo, J. M. Lema, M. T. Moreira
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Laccases (benzenediol oxygen oxidoreductases, EC 1.10.3.2) are excellent biocatalysts for biotechnological and environmental applications because of their high activity, selectivity, and specificity. Specifically, these characteristics allow them to perform the oxidation of recalcitrant compounds with simple requirements for the catalysis (presence of molecular oxygen). Nevertheless, the low stability under unfavorable conditions (pH, inactivating agents or temperature) and high production costs still limits their use for practical applications. Immobilization of enzymes has proven particularly valuable to avoid some of the aforementioned drawbacks. Magnetic nanoparticles (MNPs) have received increasing attention as carriers for enzyme immobilization since they can potentially provide an easy recovery of the biocatalyst from the reaction medium under an external magnetic field. In the present work, silica-coated magnetic nanoparticles (Fe3O4@SiO2) were prepared, characterized and used for laccase immobilization by covalent binding. The synthesis of Fe3O4@SiO2 was performed in a two-step procedure: co-precipitation and reverse microemulsion. The influence of immobilization conditions: concentrations of the functionalization agent (3-aminopropyl-triethoxy-silane) and the cross-linker (glutaraldehyde) as well as the influence of pH, T or inactivating agents were evaluated. In general, immobilized laccase showed superior stability compared to that of free enzyme. The reusability of the biocatalyst was demonstrated in successive batch reactions, where enzyme activity was maintained above 65% after 8 cycles of oxidation of the substrate 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate).Keywords: silica-coated magnetic nanoparticles, laccase, immobilization, regeneration
Procedia PDF Downloads 2181328 Ergosterol Biosynthesis: Non-Conventional Method for Improving Process
Authors: Madalina Postaru, Alexandra Tucaliuc, Dan Cascaval, Anca Irina Galaction
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Ergosterol (ergosta-5,7,22-trien-3β-ol) is the precursor of vitamin D2 (ergocalciferol), known as provitamin D2 as it is converted under UV radiation to this vitamin. The natural sources of ergosterol are mainly the yeasts (Saccharomyces sp., Candida sp.), but it can be also found in fungus (Claviceps sp.) or plants (orchids). As ergosterol is mainly accumulated in yeast cell membranes, especially in free form in the plasma-membrane, and the chemical synthesis of ergosterol does not represent an efficient method for its production, this study aimed to analyze the influence of aeration efficiency on ergosterol production by S. cerevisiae in batch and fed-batch fermentations, by considering different levels of mixing intensity, aeration rate, and n-dodecane concentration. Our previous studies on ergosterol production by S. cerevisiae in batch and fed-batch fermentation systems indicated that the addition of n-dodecane led to the increase of almost 50% of this sterol concentration, the highest productivity being reached for the fed-batch process. The experiments were carried out in a laboratory stirred bioreactor, provided with computer-controlled and recorded parameters. In batch fermentation system, the study indicated that the oxygen mass transfer coefficient, kLa, is amplified for about 3 times by increasing the volumetric concentration of n-dodecane from 0 to 15%. Moreover, the increase of dissolved oxygen concentration by adding n-dodecane leads to the diminution for 3.5 times of the produced alcohol amount. In fed-batch fermentation process, the positive influence of hydrocarbon on oxygen transfer rate is amplified mainly at its higher concentration level, as the result of the increased yeasts cells amount. Thus, by varying n-dodecane concentration from 0 to 15% vol., the kLa value increase becomes more important than for the batch fermentation, being of 4 timesKeywords: ergosterol, yeast fermentation, n-dodecane, oxygen-vector
Procedia PDF Downloads 1191327 Chitosan Hydrogel Containing Nitric Oxide Donors with Potent Antibacterial Effect
Authors: Milena Trevisan Pelegrino, Bruna De Araujo Lima, Mônica H. M. Do Nascimento, Christiane B. Lombello, Marcelo Brocchi, Amedea B. Seabra
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Nitric oxide (NO) is a small molecule involved in a wide range of physiological and pathophysiological processes, including vasodilatation, control of inflammatory pain, wound healing, and antibacterial activities. As NO is a free radical, the design of drugs that generates therapeutic amounts of NO in controlled spatial and time manners is still a challenge. In this study, the NO donor S-nitrosoglutathione (GSNO) was incorporated into the thermoresponsive Pluronic F-127 (PL) - chitosan (CS) hydrogel, in an easy and economically feasible methodology. CS is a polysaccharide with known antimicrobial and biocompatibility properties. Scanning electron microscopy, rheology and differential scanning calorimetry techniques were used for hydrogel characterization. The results demonstrated that the hydrogel has a smooth surface, thermoresponsive behavior, and good mechanical stability. The kinetics of NO release and GSNO diffusion from GSNO-containing PL/CS hydrogel demonstrated a sustained NO/GSNO release, in concentrations suitable for biomedical applications, at physiological and skin temperatures. The GSNO-PL/CS hydrogel demonstrated a concentration-dependent toxicity to Vero cells, and antimicrobial activity to Pseudomonas aeruginosa (minimum inhibitory concentration and minimum bactericidal concentration values of 0.5 µg·mL-1 of hydrogel, which correspondents to 1 mmol·L-1 of GSNO). Interesting, the concentration range in which the NO-releasing hydrogel demonstrated antibacterial effect was not found toxic to Vero mammalian cell. Thus, GSNO-PL/CS hydrogel is suitable biomaterial for topical NO delivery applications.Keywords: antimicrobial, chitosan, biocompatibility, S-nitrosothiols
Procedia PDF Downloads 1851326 Portfolio Optimization with Reward-Risk Ratio Measure Based on the Mean Absolute Deviation
Authors: Wlodzimierz Ogryczak, Michal Przyluski, Tomasz Sliwinski
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In problems of portfolio selection, the reward-risk ratio criterion is optimized to search for a risky portfolio with the maximum increase of the mean return in proportion to the risk measure increase when compared to the risk-free investments. In the classical model, following Markowitz, the risk is measured by the variance thus representing the Sharpe ratio optimization and leading to the quadratic optimization problems. Several Linear Programming (LP) computable risk measures have been introduced and applied in portfolio optimization. In particular, the Mean Absolute Deviation (MAD) measure has been widely recognized. The reward-risk ratio optimization with the MAD measure can be transformed into the LP formulation with the number of constraints proportional to the number of scenarios and the number of variables proportional to the total of the number of scenarios and the number of instruments. This may lead to the LP models with huge number of variables and constraints in the case of real-life financial decisions based on several thousands scenarios, thus decreasing their computational efficiency and making them hardly solvable by general LP tools. We show that the computational efficiency can be then dramatically improved by an alternative model based on the inverse risk-reward ratio minimization and by taking advantages of the LP duality. In the introduced LP model the number of structural constraints is proportional to the number of instruments thus not affecting seriously the simplex method efficiency by the number of scenarios and therefore guaranteeing easy solvability. Moreover, we show that under natural restriction on the target value the MAD risk-reward ratio optimization is consistent with the second order stochastic dominance rules.Keywords: portfolio optimization, reward-risk ratio, mean absolute deviation, linear programming
Procedia PDF Downloads 4071325 The Impact of Shifting Trading Pattern from Long-Haul to Short-Sea to the Car Carriers’ Freight Revenues
Authors: Tianyu Wang, Nikita Karandikar
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The uncertainty around cost, safety, and feasibility of the decarbonized shipping fuels has made it increasingly complex for the shipping companies to set pricing strategies and forecast their freight revenues going forward. The increase in the green fuel surcharges will ultimately influence the automobile’s consumer prices. The auto shipping demand (ton-miles) has been gradually shifting from long-haul to short-sea trade over the past years following the relocation of the original equipment manufacturer (OEM) manufacturing to regions such as South America and Southeast Asia. The objective of this paper is twofold: 1) to investigate the car-carriers freight revenue development over the years when the trade pattern is gradually shifting towards short-sea exports 2) to empirically identify the quantitative impact of such trade pattern shifting to mainly freight rate, but also vessel size, fleet size as well as Green House Gas (GHG) emission in Roll on-Roll Off (Ro-Ro) shipping. In this paper, a model of analyzing and forecasting ton-miles and freight revenues for the trade routes of AS-NA (Asia to North America), EU-NA (Europe to North America), and SA-NA (South America to North America) is established by deploying Automatic Identification System (AIS) data and the financial results of a selected car carrier company. More specifically, Wallenius Wilhelmsen Logistics (WALWIL), the Norwegian Ro-Ro carrier listed on Oslo Stock Exchange, is selected as the case study company in this paper. AIS-based ton-mile datasets of WALWIL vessels that are sailing into North America region from three different origins (Asia, Europe, and South America), together with WALWIL’s quarterly freight revenues as reported in trade segments, will be investigated and compared for the past five years (2018-2022). Furthermore, ordinary‐least‐square (OLS) regression is utilized to construct the ton-mile demand and freight revenue forecasting. The determinants of trade pattern shifting, such as import tariffs following the China-US trade war and fuel prices following the 0.1% Emission Control Areas (ECA) zone requirement after IMO2020 will be set as key variable inputs to the machine learning model. The model will be tested on another newly listed Norwegian Car Carrier, Hoegh Autoliner, to forecast its 2022 financial results and to validate the accuracy based on its actual results. GHG emissions on the three routes will be compared and discussed based on a constant emission per mile assumption and voyage distances. Our findings will provide important insights about 1) the trade-off evaluation between revenue reduction and energy saving with the new ton-mile pattern and 2) how the trade flow shifting would influence the future need for the vessel and fleet size.Keywords: AIS, automobile exports, maritime big data, trade flows
Procedia PDF Downloads 1211324 A Novel Method for Isolation of Kaempferol and Quercetin from Podophyllum Hexandrum Rhizome
Authors: S. B. Bhandare, K. S. Laddha
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Podphyllum hexandrum belonging to family berberidaceae has gained attention in phytochemical and pharmacological research as it shows excellent anticancer activity and has been used in treatment of skin diseases, sunburns and radioprotection. Chemically it contains lignans and flavonoids such as kaempferol, quercetin and their glycosides. Objective: To isolate and identify Kaempferol and Quercetin from Podophyllum rhizome. Method: The powdered rhizome of Podophyllum hexandrum was subjected to soxhlet extraction with methanol. This methanolic extract is used to obtain podophyllin. Podohyllin was extracted with ethyl acetate and this extract was then concentrated and subjected to column chromatography to obtain purified kaempferol and quercetin. Result: Isolated kaempferol, quercetin were light yellow and dark yellow in colour respectively. TLC of the isolated compounds was performed using chloroform: methanol (9:1) which showed single band on silica plate at Rf 0.6 and 0.4 for kaempferol and quercetin. UV spectrometric studies showed UV maxima (methanol) at 259, 360 nm and 260, 370 nm which are identical with standard kaempferol and quercetin respectively. Both IR spectra exhibited prominent absorption bands for free phenolic OH at 3277 and 3296.2 cm-1 and for conjugated C=O at 1597 and 1659.7 cm-1 respectively. The mass spectrum of kaempferol and quercetin showed (M+1) peak at m/z 287 and 303.09 respectively. 1H NMR analysis of both isolated compounds exhibited typical four-peak pattern of two doublets at δ 6.86 and δ 8.01 which was assigned to H-3’,5’ and H-2’,6’ respectively. Absence of signals less than δ 6.81 in the 1H NMR spectrum supported the aromatic nature of compound. Kaempferol and Quercetin showed 98.1% and 97% purity by HPLC at UV 370 nm. Conclusion: Easy and simple method for isolation of Kaempferol and Quercetin was developed and their structures were confirmed by UV, IR, NMR and mass studies. Method has shown good reproducibility, yield and purity.Keywords: flavonoids, kaempferol, podophyllum rhizome, quercetin
Procedia PDF Downloads 3041323 Role of Agriculture Equipment toward Food Security: Case Study of Agriculture Equipment Assistance during President Joko Widodo Era in Indonesia
Authors: Raihan Zahirah Mauludy Ridwan, Frisca Devi Choirina
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Indonesia is an agrarian country endowed by fertile soil, supportive weather, and natural resources which can support agricultural activities. There are commodities which produced by local farmers. Even though Indonesia had commodities, it still imports stocks of staple food. To reduce the dependency on imported staple food, President Joko Widodo wants to generate more locally-produced staple food by giving 69.000 tractors, free seeds, and fertilizers to the local farmers. In Indonesia, the problem revolves around the amount of food production especially rice derived from farmers who cannot afford technologies which can support the agricultural activities. Moreover, they cannot afford seeds and fertilizers which can make the production of commodities more effective and have high quality. Therefore, the paper would like to answer how agriculture equipment assistance during President Joko Widodo era can give significant impact towards food security. The purpose of this paper is to explore the role of agriculture equipment assistance and its impact towards Indonesia’s food security. This paper uses Boserup and Ruthenberg theory of agricultural intensification to link agriculture equipment and intensification of production which in the end will have impact towards food security through case study method. The paper affirms that the role of agricultural equipment assistance toward food security in Indonesia is significant toward Indonesia’s food production and security.Keywords: agricultural equipment, agricultural intensification, Boserup, Indonesia, Joko Widodo, Ruthenberg
Procedia PDF Downloads 1841322 Organic Co-Polymer Monolithic Columns for Liquid Chromatography Mixed Mode Protein Separations
Authors: Ahmed Alkarimi, Kevin Welham
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Organic mixed mode monolithic columns were fabricated from; glycidyl methacrylate-co-ethylene dimethacrylate-co-stearyl methacrylate, using glycidyl methacrylate and stearyl methacrylate as co monomers representing 30% and 70% respectively of the liquid volume with ethylene dimethacrylate crosslinker and 2,2-dimethoxy-2-phenylacetophenone as the free radical initiator. The monomers were mixed with a binary porogenic solvent, comprising propan-1-ol, and methanol (0.825 mL each). The monolith was formed by photo polymerization (365 nm) inside a borosilicate glass tube (1.5 mm ID and 3 mm OD x 50 mm length). The monolith was observed to have formed correctly by optical examination and generated reasonable backpressure, approximately 650 psi at a flow rate of 0.2 mL min⁻¹ 50:50 acetonitrile: water. The morphological properties of the monolithic columns were investigated using scanning electron microscopy images, and Brunauer-Emmett-Teller analysis, the results showed that the monolith was formed properly with 19.98 ± 0.01 mm² surface area, 0.0205 ± 0.01 cm³ g⁻¹ pore volume and 6.93 ± 0.01 nm average pore size. The polymer monolith formed was further investigated using proton nuclear magnetic resonance, and Fourier transform infrared spectroscopy. The monolithic columns were investigated using high-performance liquid chromatography to test their ability to separate different samples with a range of properties. The columns displayed both hydrophobic/hydrophilic and hydrophobic/ion exchange interactions with the compounds tested indicating that true mixed mode separations. The mixed mode monolithic columns exhibited significant separation of proteins.Keywords: LC separation, proteins separation, monolithic column, mixed mode
Procedia PDF Downloads 1621321 The Automatic Transliteration Model of Images of the Book Hamong Tani Using Statistical Approach
Authors: Agustinus Rudatyo Himamunanto, Anastasia Rita Widiarti
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Transliteration using Javanese manuscripts is one of methods to preserve and legate the wealth of literature in the past for the present generation in Indonesia. The transliteration manual process commonly requires philologists and takes a relatively long time. The automatic transliteration process is expected to shorten the time so as to help the works of philologists. The preprocessing and segmentation stage firstly done is used to manage the document images, thus obtaining image script units that will compile input document images free from noise and have the similarity in properties in the thickness, size, and slope. The next stage of characteristic extraction is used to find unique characteristics that will distinguish each Javanese script image. One of characteristics that is used in this research is the number of black pixels in each image units. Each image of Java scripts contained in the data training will undergo the same process similar to the input characters. The system testing was performed with the data of the book Hamong Tani. The book Hamong Tani was selected due to its content, age and number of pages. Those were considered sufficient as a model experimental input. Based on the results of random page automatic transliteration process testing, it was determined that the maximum percentage correctness obtained was 81.53%. The percentage of success was obtained in 32x32 pixel input image size with the 5x5 image window. With regard to the results, it can be concluded that the automatic transliteration model offered is relatively good.Keywords: Javanese script, character recognition, statistical, automatic transliteration
Procedia PDF Downloads 3391320 Eco-Friendly Control of Bacterial Speck on Solanum lycopersicum by Azadirachta indica Extract
Authors: Navodit Goel, Prabir K. Paul
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Tomato (Solanum lycopersicum) is attacked by Pseudomonas syringae pv. tomato causing speck lesions on the leaves leading to severe economic casualty. In the present study, aqueous fruit extracts of Azadirachta indica (neem) were sprayed on a single node of tomato plants grown under controlled contamination-free conditions. The treatment of plants was performed with neem fruit extract either alone or along with the pathogen. The parameters of observation were activities of polyphenol oxidase (PPO) and lysozyme, and isoform analysis of PPO; both at the treated leaves as well as untreated leaves away from the site of extract application. Polyphenol oxidase initiates phenylpropanoid pathway resulting in the synthesis of quinines from cytoplasmic phenols and production of reactive oxygen species toxic to broad spectrum microbes. Lysozyme is responsible for the breakdown of bacterial cell wall. The results indicate the upregulation of PPO and lysozyme activities in both the treated and untreated leaves along with de novo expression of newer PPO isoenzymes (which were absent in control samples). The appearance of additional PPO isoenzymes in bioelicitor-treated plants indicates that either the isoenzymes were expressed after bioelicitor application or the already expressed but inactive isoenzymes were activated by it. Lysozyme activity was significantly increased in the plants when treated with the bioelicitor or the pathogen alone. However, no new isoenzymes of lysozyme were expressed upon application of the extract. Induction of resistance by neem fruit extract could be a potent weapon in eco-friendly plant protection strategies.Keywords: Azadirachta indica, lysozyme, polyphenol oxidase, Solanum lycopersicum
Procedia PDF Downloads 2881319 Biotechnological Recycling of Apple By-Products: A Reservoir Model to Produce a Dietary Supplement Fortified with Biogenic Phenolic Compounds
Authors: Ali Zein Aalabiden Tlais, Alessio Da Ros, Pasquale Filannino, Olimpia Vincentini, Marco Gobbetti, Raffaella Di Cagno
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This study is an example of apple by-products (AP) recycling through a designed fermentation by selected autochthonous Lactobacillus plantarum AFI5 and Lactobacillus fabifermentans ALI6 used singly or as binary cultures with the selected Saccharomyces cerevisiae AYI7. Compared to Raw-, Unstarted- and Chemically Acidified-AP, Fermented-AP promoted the highest levels of total and insoluble dietary fibers, antioxidant activity, and free phenolics. The binary culture of L. plantarum AFI5 and S. cerevisiae AYI7 had the best effect on the bioavailability phenolic compounds as resulted by the Liquid chromatography-mass spectrometry validated method. The accumulation of phenolic acid derivatives highlighted microbial metabolism during AP fermentation. Bio-converted phenolic compounds were likely responsible for the increased antioxidant activity. The potential health-promoting effects of Fermented-AP were highlighted using Caco-2 cells. With variations among single and binary cultures, fermented-AP counteracted the inflammatory processes and the effects of oxidative stress in Caco-2 cells and preserved the integrity of tight junctions. An alternative and suitable model for food by-products recycling to manufacture a dietary supplement fortified with biogenic compounds was proposed. Highlighting the microbial metabolism of several phenolic compounds, undoubted additional value to such downstream wastes was created.Keywords: apple by-products, antioxidant, fermentation, phenolic compounds
Procedia PDF Downloads 1411318 Encapsulation of Probiotic Bacteria in Complex Coacervates
Authors: L. A. Bosnea, T. Moschakis, C. Biliaderis
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Two probiotic strains of Lactobacillus paracasei subsp. paracasei (E6) and Lactobacillus paraplantarum (B1), isolated from traditional Greek dairy products, were microencapsulated by complex coacervation using whey protein isolate (WPI, 3% w/v) and gum arabic (GA, 3% w/v) solutions mixed at different polymer ratio (1:1, 2:1 and 4:1). The effect of total biopolymer concentration on cell viability was assessed using WPI and GA solutions of 1, 3 and 6% w/v at a constant ratio of 2:1. Also, several parameters were examined for optimization of the microcapsule formation, such as inoculum concentration and the effect of ionic strength. The viability of the bacterial cells during heat treatment and under simulated gut conditions was also evaluated. Among the different WPI/GA weight ratios tested (1:1, 2:1, and 4:1), the highest survival rate was observed for the coacervate structures made with the ratio of 2:1. The protection efficiency at low pH values is influenced by both concentration and the ratio of the added biopolymers. Moreover, the inoculum concentration seems to affect the efficiency of microcapsules to entrap the bacterial cells since an optimum level was noted at less than 8 log cfu/ml. Generally, entrapment of lactobacilli in the complex coacervate structure enhanced the viability of the microorganisms when exposed to a low pH environment (pH 2.0). Both encapsulated strains retained high viability in simulated gastric juice (>73%), especially in comparison with non-encapsulated (free) cells (<19%). The encapsulated lactobacilli also exhibited enhanced viability after 10–30 min of heat treatment (65oC) as well as at different NaCl concentrations (pH 4.0). Overall, the results of this study suggest that complex coacervation with WPI/GA has a potential to deliver live probiotics in low pH food systems and fermented dairy products; the complexes can dissolve at pH 7.0 (gut environment), releasing the microbial cells.Keywords: probiotic, complex coacervation, whey, encapsulation
Procedia PDF Downloads 2971317 Appliance of the Analytic Hierarchy Process Methodology for the Selection of a Small Modular Reactors to Enhance Maritime Traffic Decarbonisation
Authors: Sara Martín, Ying Jie Zheng, César Hueso
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International shipping is considered one of the largest sources of pollution in the world, accounting for 812 million tons of CO2 emissions in the year 2018. Current maritime decarbonisation is based on the implementation of new fuel alternatives, such as LNG, biofuels, and methanol, among others, which are less polluting as well as less efficient. Despite being a carbon-free and highly-developed technology, nuclear propulsion is hardly discussed as an alternative. Scientifically, it is believed that Small Modular Reactors (SMR) could be a promising solution to decarbonized maritime traffic due to their small dimensions and safety capabilities. However, as of today, there are no merchant ships powered by nuclear systems. Therefore, this project aims to understand the challenges of the development of nuclear-fuelled vessels by analysing all SMR designs to choose the most suitable one. In order not to fall into subjectivities, the Analytic Hierarchy Process (AHP) will be used to make the selection. This multiple-criteria evaluation technique analyses complex decisions by pairwise comparison of a number of evaluation criteria that can be applied to each SMR. The state-of-the-art 72 SMRs presented by the International Atomic Energy Agency (IAEA) will be analysed and ranked by a global parameter, calculated by applying the AHP methodology. The main target of the work is to find an adequate SMR system to power a ship. Top designs will be described in detail, and conclusions will be drawn from the results. This project has been conceived as an effort to foster the near-term development of zero-emission maritime traffic.Keywords: international shipping, decarbonization, SMR, AHP, nuclear-fuelled vessels
Procedia PDF Downloads 1251316 Vibration Analysis of Magnetostrictive Nano-Plate by Using Modified Couple Stress and Nonlocal Elasticity Theories
Authors: Hamed Khani Arani, Mohammad Shariyat, Armaghan Mohammadian
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In the present study, the free vibration of magnetostrictive nano-plate (MsNP) resting on the Pasternak foundation is investigated. Firstly, the modified couple stress (MCS) and nonlocal elasticity theories are compared together and taken into account to consider the small scale effects; in this paper not only two theories are analyzed but also it improves the MCS theory is more accurate than nonlocal elasticity theory in such problems. A feedback control system is utilized to investigate the effects of a magnetic field. First-order shear deformation theory (FSDT), Hamilton’s principle and energy method are utilized in order to drive the equations of motion and these equations are solved by differential quadrature method (DQM) for simply supported boundary conditions. The MsNP undergoes in-plane forces in x and y directions. In this regard, the dimensionless frequency is plotted to study the effects of small scale parameter, magnetic field, aspect ratio, thickness ratio and compression and tension loads. Results indicate that these parameters play a key role on the natural frequency. According to the above results, MsNP can be used in the communications equipment, smart control vibration of nanostructure especially in sensor and actuators such as wireless linear micro motor and smart nano valves in injectors.Keywords: feedback control system, magnetostrictive nano-plate, modified couple stress theory, nonlocal elasticity theory, vibration analysis
Procedia PDF Downloads 1351315 Low-Surface Roughness and High Optical Quality CdS Thin Film Grown by Modified Chemical Surface Deposition Method
Authors: A. Elsayed, M. H. Dewaidar, M. Ghali
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We report on deposition of smooth, pinhole-free, low-surface roughness ( < 4nm) and high optical quality cadmium sulfide (CdS) thin films on glass substrates using our new method based on chemical surface deposition principle. In this method, cadmium acetate and thiourea are used as reactants under special growth conditions for deposition of CdS films. X-ray diffraction (XRD) measurements were used to examine the crystal structure properties of the deposited CdS films. In addition, UV-vis transmittance and low-temperature (4K) photoluminescence (PL) measurements were performed for quantifying optical properties of the deposited films. Interestingly, we found that XRD pattern of the deposited films has dramatically changed when the growth temperature was raised during the reaction. Namely, the XRD measurements reveal a structural change of CdS film from Cubic to Hexagonal phase upon increase in the growth temperature from 75 °C to 200 °C. Furthermore, the deposited films show high optical quality as confirmed from observation of both sharp edge in the transmittance spectra and strong PL intensity at room temperature. Also, we found a strong effect of the growth conditions on the optical band gap of the deposited films; where remarkable red-shift in the absorption edge with temperature is clearly seen in both transmission and PL spectra. Such tuning of both optical band gap and crystal structure of the deposited CdS films; can be utilized for tuning the electronic bands alignments between CdS and other light harvesting materials, like CuInGaSe or CdTe, for potential improvement in the efficiency of all-solution processed solar cells devices based on these heterostructures.Keywords: thin film, CdS, new method, optical properties
Procedia PDF Downloads 2601314 Preparation of Frozen Bivalent Babesial (Babesia Bovis and Babesia Bigemina) Vaccine from Field Isolates and Evaluation of Its Efficacy in Calves
Authors: Muhammad Fiaz Qamar, Ahmad Faraz, Muhammad Arfan Zaman, Kazim Ali, Waleed Akram
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Babesiosis is reflected as the most important disease of cattle that are transmitted by arthropods. In Pakistan, its prevalence is up to 29% in the cattle and buffalo population in different regions. Cattle show a long lasting and durable immunity by giving an infection of B.bovis, B. bigemina, or Babesiadivergens. this is used in cattle to immunize them in a few countries as anti-babesiosis vaccine. Development of frozen vaccine allows for complete testing after production of each batch, However, once thawed, its reduced its shelf life, frozen vaccines are more difficult to transport as well as expensive to produce as compared to chilled vaccine. The contamination of blood derived vaccine has the potential risk that makes pre-production and post-production quality control necessary. For the trail master seed production of whole blood frozen bivalent Babesia(Babesiabovis and Babesiabigemina), 100 blood samples of Babesial positive suspected cattle was taken and processed for separation microscopic detection and rectification by PCR. Vaccine passages were done to reduce the parasitaemiasis in live calves. After 8 passages, parasitemia of Babesia reduced from 80% to 15%. Infected donor calf’s blood was taken by jugular cannulation by using preservative free lithium heparin as an anticoagulant (5 International Units IU heparin/ml blood). In lab, parasite containing blood was mixed in equal volumes with 3 M glycerol in PBS supplemented with 5 mM glucose (final concentration of glycerol 1.5 M) at 37°C. The mixture was then equilibrized at 37°C for 30 minutes and were dispensed in required containers (e.g., 5 ml cryovials).Keywords: distribution, babesia, primer sequences, PCV
Procedia PDF Downloads 1041313 Exploring Psychosocial Factors That Enable Teachers to Cope with Workplace Adversity at a Rural District School Setting
Authors: K. R. Mukuna
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Teachers are faced many challenges in the South African rural schools such as stress, depression, lack of resources, poor working relationships, inflexible curriculum etc. These could affect their wellbeing and effectiveness at the workplace. As a result, the study had a significance in the teacher’s lives, and community due teachers worked under conditions that are unfavourable to perform their jobs effectively. Despite these conditions, they still managed to do their jobs and the community is uplifted. However, this study aimed to explore factors that enable teachers to cope with workplace adversities at a rural school district in the Free State Province. It adopted a qualitative case study as a research design. Semi-structured interviews and colleges had employed as tools to collect data. Ten participants (n=10; 5 males and 5 females) were selected through purposive and convenience sampling. All participants selected from a South African rural school. Sesotho culture was their home language, and most of them had 5 years of teaching experiences. The thematic findings revealed that they developed abilities to cope with and adjust to the social and cultural environment. These included self-efficacy, developing problem-solving skills, awareness of strengths and asserts, self-managing of emotions, and self-confidence. This study concluded that these psychosocial factors contributed to coping with teacher’s diversities, and effectively stabilized their wellbeing in the schools.Keywords: psychosocial factors, teachers counselling, teacher stress, workplace adversity, rural school, teachers’ wellbeing, teachers’ resilience, teachers’ self-efficacy, social interaction
Procedia PDF Downloads 1271312 Early Evaluation of Long-Span Suspension Bridges Using Smartphone Accelerometers
Authors: Ekin Ozer, Maria Q. Feng, Rupa Purasinghe
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Structural deterioration of bridge systems possesses an ongoing threat to the transportation networks. Besides, landmark bridges’ integrity and safety are more than sole functionality, since they provide a strong presence for the society and nations. Therefore, an innovative and sustainable method to inspect landmark bridges is essential to ensure their resiliency in the long run. In this paper, a recently introduced concept, smartphone-based modal frequency estimation is addressed, and this paper targets to authenticate the fidelity of smartphone-based vibration measurements gathered from three landmark suspension bridges. Firstly, smartphones located at the bridge mid-span are adopted as portable and standalone vibration measurement devices. Then, their embedded accelerometers are utilized to gather vibration response under operational loads, and eventually frequency domain characteristics are deduced. The preliminary analysis results are compared with the reference publications and high-quality monitoring data to validate the usability of smartphones on long-span landmark suspension bridges. If the technical challenges such as high period of vibration, low amplitude excitation, embedded smartphone sensor features, sampling, and citizen engagement are tackled, smartphones can provide a novel and cost-free crowdsourcing tool for maintenance of these landmark structures. This study presents the early phase findings from three signature structures located in the United States.Keywords: smart and mobile sensing, structural health monitoring, suspension bridges, vibration analysis
Procedia PDF Downloads 2921311 A BIM-Based Approach to Assess COVID-19 Risk Management Regarding Indoor Air Ventilation and Pedestrian Dynamics
Authors: T. Delval, C. Sauvage, Q. Jullien, R. Viano, T. Diallo, B. Collignan, G. Picinbono
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In the context of the international spread of COVID-19, the Centre Scientifique et Technique du Bâtiment (CSTB) has led a joint research with the French government authorities Hauts-de-Seine department, to analyse the risk in school spaces according to their configuration, ventilation system and spatial segmentation strategy. This paper describes the main results of this joint research. A multidisciplinary team involving experts in indoor air quality/ventilation, pedestrian movements and IT domains was established to develop a COVID risk analysis tool based on Building Information Model. The work started with specific analysis on two pilot schools in order to provide for the local administration specifications to minimize the spread of the virus. Different recommendations were published to optimize/validate the use of ventilation systems and the strategy of student occupancy and student flow segmentation within the building. This COVID expertise has been digitized in order to manage a quick risk analysis on the entire building that could be used by the public administration through an easy user interface implemented in a free BIM Management software. One of the most interesting results is to enable a dynamic comparison of different ventilation system scenarios and space occupation strategy inside the BIM model. This concurrent engineering approach provides users with the optimal solution according to both ventilation and pedestrian flow expertise.Keywords: BIM, knowledge management, system expert, risk management, indoor ventilation, pedestrian movement, integrated design
Procedia PDF Downloads 1071310 Black-Legged Tick (Ixodes Scapularis) Impacts on Hematology and Ectoparasite Communities of Peromyscus Mice
Authors: Erica Fellin, Albrecht Schulte-Hostedde
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As the climate warms, the black-legged tick’s (Ixodes scapularis) range expands further north in Ontario, Canada, reaching new host populations that have not previously interacted with this blood-feeding parasite. Peromyscus mice in these northern areas are unfamiliar and inexperienced to the effects of these ticks compared to their southern counterparts that have adapted to living with these organisms. The purpose of this study was to see if there is a difference in physiology between these two groups – deer mice living in areas where tick populations have established and deer mice living in black-legged tick-free environments – looking specifically to see if there is significant variation in hemoglobin levels, which can negatively impact how these mice function in their environment. Along with this, a comparison of the parasite community structure on these mice hosts was analyzed to see if ticks change the composition of these micro-environments. Blood samples were collected from individual mice from populations where black-legged ticks were either present or absent to assess haemoglobin levels. At the same time, ectoparasites were collected from these same mice to determine parasite loads and species diversity. Haemoglobin levels were found to be lower when tick loads were high, and parasite diversity appeared to be higher when ticks were absent. Since black-legged ticks are carriers of many pathogens that can be passed on to humans, including Lyme’s disease, it is important to understand their movement and distribution across Ontario as well as their interactions with their hosts (and co-occurring parasites) in their environments.Keywords: community ecology, hematology, hosts, parasites
Procedia PDF Downloads 1411309 Chaupadi Practice: A Cruel Discrimination against Women a Case Study of Achham District of Nepal
Authors: Santosh Thapa, Sankar Gurung
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Chaupadi is a tradition widely practiced in the far and mid-western region of Nepal. It is a practice where girls and women are not allowed to inter the house and touch the food, water and milk during their menstruation period of 4-7 days. They have to spend all the nights during the period in a specific hut (Chhaupadi Goth) which is a bit far from their residence where they faces various kinds of risk and violence like bullying, snakes and insect bite, wild animal attack etc. Sometimes the girls even do not go to school during their menstruation periods. After childbirth, the woman must stay in a cow shed for 11 days in such Chhaupadi practiced areas. This study limits the Achham district of the far western region which is the most vulnerable Chhaupadi practicing district. Several governmental and non-governmental organizations have been involving and spending huge amount of money for capacity building and awareness raising campaign for last 2 decades but still 9 out of 75 Village Development Committees (VDCs) have been partially practicing Chaupadi in the district. This study shows that the school attendance rate of the girls during the period have visibly increased which helps to increase the number of the girl graduation as well. Similarly, the practice of Chhaupadi is one of the reasons for increasing the number of cases of uterus prolapsus and poor reproductive health of women and girls. Triggering tools are the one of the best ways to accelerate the awareness campaign in the VDCs. This study recommends that the local bodies should coordinate and lead the overall awareness campaign program to sustain the Chaupadi free VDCs.Keywords: awareness campaign, chaupadi practice, gender discrimination, violence
Procedia PDF Downloads 3101308 Effect of Dissolved Oxygen Concentration on Iron Dissolution by Liquid Sodium
Authors: Sami Meddeb, M. L Giorgi, J. L. Courouau
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This work presents the progress of studies aiming to guarantee the lifetime of 316L(N) steel in a sodium-cooled fast reactor by determining the elementary corrosion mechanism, which is akin to an accelerated dissolution by dissolved oxygen. The mechanism involving iron, the main element of steel, is particularly studied in detail, from the viewpoint of the data available in the literature, the modeling of the various mechanisms hypothesized. Experiments performed in the CORRONa facility at controlled temperature and dissolved oxygen content are used to test both literature data and hypotheses. Current tests, performed at various temperatures and oxygen content, focus on specifying the chemical reaction at play, determining its free enthalpy, as well as kinetics rate constants. Specific test configuration allows measuring the reaction kinetics and the chemical equilibrium state in the same test. In the current state of progress of these tests, the dissolution of iron accelerated by dissolved oxygen appears as directly related to a chemical complexation reaction of mixed iron-sodium oxide (Na-Fe-O), a compound that is soluble in the liquid sodium solution. Results obtained demonstrate the presence in the solution of this corrosion product, whose kinetics is the limiting step under the conditions of the test. This compound, the object of hypotheses dating back more than 50 years, is predominant in solution compared to atomic iron, presumably even for the low oxygen concentration, and cannot be neglected for the long-term corrosion modeling of any heat transfer system.Keywords: corrosion, sodium fast reactors, iron, oxygen
Procedia PDF Downloads 179