Search results for: tar elimination
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 409

Search results for: tar elimination

139 A New Cytoprotective Drug on the Basis of Cytisine: Phase I Clinical Trial Results

Authors: B. Yermekbayeva, A. Gulyayaev, T. Nurgozhin, C. Bektur

Abstract:

Cytisine aminophosphonate under the name "Cytafat" was approved for clinical trials in Republic of Kazakhstan as a putative liver protecting drug for the treatment of acute toxic hepatitis. A method of conducting the clinical trial is a double blind study. Total number of patients -71, aged from 16 to 56 years. Research on healthy volunteers determined the maximal tolerable doze of "Cytafat" as 200 mg/kg. Side effects when administered at high dozes (100-200 mg/kg) are tachycardia and increase of arterial blood pressure. The drug is tested in the treatment of 28 patients with a syndrome of hepatocellular failure (a poisoning with substitutes of alcohol, rat poison, or medical products). "Cytafat" was intravenously administered at a dose of 10 mg/kg in 200 ml of 5 % glucose solution once daily. The number of administrations: 1-3. In the comparison group, 23 patients were treated intravenously once a day with “Essenciale H” at a dose of 10 ml. 20 patients received a placebo (10 ml of glucose intravenously). In all cases of toxic hepatopathology the significant positive clinical effect of the testing drug distinguishable from placebo and surpassing the alternative was observed. Within a day after administration a sharp reduction of cytolitic syndrome parameters (ALT, AST, alkaline phosphatase, thymol turbidity test, GGT) was registered, a reduction of the severity of cholestatic syndrome (bilirubin decreased) was recorded, significantly decreased indices of lipid peroxidation. The following day, in all cases the positive dynamics was determined with ultrasound study (reduction of diffuse changes and events of reactive pancreatitis), hepatomegaly disappeared. Normalization of all parameters occurred in 2-3 times faster, than when using the drug "Essenciale H" and placebo. Average term of elimination of toxic hepatopathy when using the drug "Cytafat" -2,8 days, "Essenciale H" -7,2 days, and placebo -10,6 days. The new drug "Cytafat" has expressed cytoprotective properties.

Keywords: cytisine, cytoprotection, hepatopathy, hepatoprotection

Procedia PDF Downloads 337
138 A Proposed Optimized and Efficient Intrusion Detection System for Wireless Sensor Network

Authors: Abdulaziz Alsadhan, Naveed Khan

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In recent years intrusions on computer network are the major security threat. Hence, it is important to impede such intrusions. The hindrance of such intrusions entirely relies on its detection, which is primary concern of any security tool like Intrusion Detection System (IDS). Therefore, it is imperative to accurately detect network attack. Numerous intrusion detection techniques are available but the main issue is their performance. The performance of IDS can be improved by increasing the accurate detection rate and reducing false positive. The existing intrusion detection techniques have the limitation of usage of raw data set for classification. The classifier may get jumble due to redundancy, which results incorrect classification. To minimize this problem, Principle Component Analysis (PCA), Linear Discriminant Analysis (LDA), and Local Binary Pattern (LBP) can be applied to transform raw features into principle features space and select the features based on their sensitivity. Eigen values can be used to determine the sensitivity. To further classify, the selected features greedy search, back elimination, and Particle Swarm Optimization (PSO) can be used to obtain a subset of features with optimal sensitivity and highest discriminatory power. These optimal feature subset used to perform classification. For classification purpose, Support Vector Machine (SVM) and Multilayer Perceptron (MLP) used due to its proven ability in classification. The Knowledge Discovery and Data mining (KDD’99) cup dataset was considered as a benchmark for evaluating security detection mechanisms. The proposed approach can provide an optimal intrusion detection mechanism that outperforms the existing approaches and has the capability to minimize the number of features and maximize the detection rates.

Keywords: Particle Swarm Optimization (PSO), Principle Component Analysis (PCA), Linear Discriminant Analysis (LDA), Local Binary Pattern (LBP), Support Vector Machine (SVM), Multilayer Perceptron (MLP)

Procedia PDF Downloads 336
137 Healthy Feeding and Drinking Troughs for Profitable Intensive Deep-Litter Poultry Farming

Authors: Godwin Ojochogu Adejo, Evelyn UnekwuOjo Adejo, Sunday UnenwOjo Adejo

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The mainstream contemporary approach to controlling the impact of diseases among poultry birds rely largely on curative measures through the administration of drugs to infected birds. Most times as observed in the deep liter poultry farming system, entire flocks including uninfected birds receive the treatment they do not need. As such, unguarded use of chemical drugs and antibiotics has led to wastage and accumulation of chemical residues in poultry products with associated health hazards to humans. However, wanton and frequent drug usage in poultry is avoidable if feeding and drinking equipment are designed to curb infection transmission among birds. Using toxicological assays as guide and with efficiency and simplicity in view, two newly field-tested and recently patented equipments called 'healthy liquid drinking trough (HDT)' and 'healthy feeding trough (HFT)' that systematically eliminate contamination of the feeding and drinking channels, thereby, curbing wide-spread infection and transmission of diseases in the (intensive) deep litter poultry farming system were designed. Upon combined usage, they automatically and drastically reduced both the amount and frequency of antibiotics use in poultry by over > 50%. Additionally, they conferred optimization of feed and water utilization/elimination of wastage by > 80%, reduced labour by > 70%, reduced production cost by about 15%, and reduced chemical residues in poultry meat or eggs by > 85%. These new and cheap technologies which require no energy input are likely to elevate safety of poultry products for consumers' health, increase marketability locally and for export, and increase output and profit especially among poultry farmers and poor people who keep poultry or inevitably utilize poultry products in developing countries.

Keywords: healthy, trough, toxicological, assay-guided, poultry

Procedia PDF Downloads 129
136 Habitat-Specific Divergences in the Gene Repertoire among the Reference Prevotella Genomes of the Human Microbiome

Authors: Vinod Kumar Gupta, Narendrakumar M. Chaudhari, Suchismitha Iskepalli, Chitra Dutta

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Background-The community composition of the human microbiome is known to vary at distinct anatomical niches. But little is known about the nature of variations if any, at the genome/sub-genome levels of a specific microbial community across different niches. The present report aims to explore, as a case study, the variations in gene repertoire of 28 Prevotella reference draft genomes derived from different body-sites of human, as reported earlier by the Human Microbiome Consortium. Results-The analysis reveals the exclusive presence of 11798, 3673, 3348 and 934 gene families and exclusive absence of 17, 221, 115 and 645 gene families in Prevotella genomes derived from the human oral cavity, gastro-intestinal tracts (GIT), urogenital tract (UGT) and skin, respectively. The pan-genome for Prevotella remains “open”. Distribution of various functional COG categories differs appreciably among the habitat-specific genes, within Prevotella pan-genome and between the GIT-derived Bacteroides and Prevotella. The skin and GIT isolates of Prevotella are enriched in singletons involved in Signal transduction mechanisms, while the UGT and oral isolates show higher representation of the Defense mechanisms category. No niche-specific variations could be observed in the distribution of KEGG pathways. Conclusion-Prevotella may have developed distinct genetic strategies for adaptation to different anatomical habitats through selective, niche-specific acquisition and elimination of suitable gene-families. In addition, individual microorganisms tend to develop their own distinctive adaptive stratagems through large repertoires of singletons. Such in situ, habitat-driven refurbishment of the genetic makeup can impart substantial intra-lineage genome diversity within the microbes without perturbing their general taxonomic heritage.

Keywords: body niche adaptation, human microbiome, pangenome, Prevotella

Procedia PDF Downloads 226
135 Achieving Process Stability through Automation and Process Optimization at H Blast Furnace Tata Steel, Jamshedpur

Authors: Krishnendu Mukhopadhyay, Subhashis Kundu, Mayank Tiwari, Sameeran Pani, Padmapal, Uttam Singh

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Blast Furnace is a counter current process where burden descends from top and hot gases ascend from bottom and chemically reduce iron oxides into liquid hot metal. One of the major problems of blast furnace operation is the erratic burden descent inside furnace. Sometimes this problem is so acute that burden descent stops resulting in Hanging and instability of the furnace. This problem is very frequent in blast furnaces worldwide and results in huge production losses. This situation becomes more adverse when blast furnaces are operated at low coke rate and high coal injection rate with adverse raw materials like high alumina ore and high coke ash. For last three years, H-Blast Furnace Tata Steel was able to reduce coke rate from 450 kg/thm to 350 kg/thm with an increase in coal injection to 200 kg/thm which are close to world benchmarks and expand profitability. To sustain this regime, elimination of irregularities of blast furnace like hanging, channeling, and scaffolding is very essential. In this paper, sustaining of zero hanging spell for consecutive three years with low coke rate operation by improvement in burden characteristics, burden distribution, changes in slag regime, casting practices and adequate automation of the furnace operation has been illustrated. Models have been created to comprehend and upgrade the blast furnace process understanding. A model has been developed to predict the process of maintaining slag viscosity in desired range to attain proper burden permeability. A channeling prediction model has also been developed to understand channeling symptoms so that early actions can be initiated. The models have helped to a great extent in standardizing the control decisions of operators at H-Blast Furnace of Tata Steel, Jamshedpur and thus achieving process stability for last three years.

Keywords: hanging, channelling, blast furnace, coke

Procedia PDF Downloads 162
134 The Use of Additives to Prevent Fouling in Polyethylene and Polypropylene Gas and Slurry Phase Processes

Authors: L. Shafiq, A. Rigby

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All polyethylene processes are highly exothermic, and the safe removal of the heat of reaction is a fundamental issue in the process design. In slurry and gas processes, the velocity of the polymer particles in the reactor and external coolers can be very high, and under certain conditions, this can lead to static charging of these particles. Such static charged polymer particles may start building up on the reactor wall, limiting heat transfer, and ultimately leading to severe reactor fouling and forced reactor shut down. Statsafe™ is an FDA approved anti-fouling additive currently used around the world for polyolefin production as an anti-fouling additive. The unique polymer chemistry aids static discharge, which prevents the build-up of charged polyolefin particles, which could lead to fouling. Statsafe™ is being used and trailed in gas, slurry, and a combination of these technologies around the world. We will share data to demonstrate how the use of Statsafe™ allows more stable operation at higher solids level by eliminating static, which would otherwise prevent closer packing of particles in the hydrocarbon slurry. Because static charge generation depends also on the concentration of polymer particles in the slurry, the maximum slurry concentration can be higher when using Statsafe™, leading to higher production rates. The elimination of fouling also leads to less downtime. Special focus will be made on the impact anti-static additives have on catalyst performance within the polymerization process and how this has been measured. Lab-scale studies have investigated the effect on the activity of Ziegler Natta catalysts when anti-static additives are used at various concentrations in gas and slurry, polyethylene and polypropylene processes. An in-depth gas phase study investigated the effect of additives on the final polyethylene properties such as particle size, morphology, fines, bulk density, melt flow index, gradient density, and melting point.

Keywords: anti-static additives, catalyst performance, FDA approved anti-fouling additive, polymerisation

Procedia PDF Downloads 163
133 Experimental Study of an Isobaric Expansion Heat Engine with Hydraulic Power Output for Conversion of Low-Grade-Heat to Electricity

Authors: Maxim Glushenkov, Alexander Kronberg

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Isobaric expansion (IE) process is an alternative to conventional gas/vapor expansion accompanied by a pressure decrease typical of all state-of-the-art heat engines. The elimination of the expansion stage accompanied by useful work means that the most critical and expensive parts of ORC systems (turbine, screw expander, etc.) are also eliminated. In many cases, IE heat engines can be more efficient than conventional expansion machines. In addition, IE machines have a very simple, reliable, and inexpensive design. They can also perform all the known operations of existing heat engines and provide usable energy in a very convenient hydraulic or pneumatic form. This paper reports measurement made with the engine operating as a heat-to-shaft-power or electricity converter and a comparison of the experimental results to a thermodynamic model. Experiments were carried out at heat source temperature in the range 30–85 °C and heat sink temperature around 20 °C; refrigerant R134a was used as the engine working fluid. The pressure difference generated by the engine varied from 2.5 bar at the heat source temperature 40 °C to 23 bar at the heat source temperature 85 °C. Using a differential piston, the generated pressure was quadrupled to pump hydraulic oil through a hydraulic motor that generates shaft power and is connected to an alternator. At the frequency of about 0.5 Hz, the engine operates with useful powers up to 1 kW and an oil pumping flowrate of 7 L/min. Depending on the temperature of the heat source, the obtained efficiency was 3.5 – 6 %. This efficiency looks very high, considering such a low temperature difference (10 – 65 °C) and low power (< 1 kW). The engine’s observed performance is in good agreement with the predictions of the model. The results are very promising, showing that the engine is a simple and low-cost alternative to ORC plants and other known energy conversion systems, especially at low temperatures (< 100 °C) and low power range (< 500 kW) where other known technologies are not economic. Thus low-grade solar, geothermal energy, biomass combustion, and waste heat with a temperature above 30 °C can be involved into various energy conversion processes.

Keywords: isobaric expansion, low-grade heat, heat engine, renewable energy, waste heat recovery

Procedia PDF Downloads 186
132 Optimization of an Electro-Submersible Pump for Crude Oil Extraction Processes

Authors: Deisy Becerra, Nicolas Rios, Miguel Asuaje

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The Electrical Submersible Pump (ESP) is one of the most artificial lifting methods used in the last years, which consists of a serial arrangement of centrifugal pumps. One of the main concerns when handling crude oil is the formation of O/W or W/O (oil/water or water/oil) emulsions inside the pump, due to the shear rate imparted and the presence of high molecular weight substances that act as natural surfactants. Therefore, it is important to perform an analysis of the flow patterns inside the pump to increase the percentage of oil recovered using the centrifugal force and the difference in density between the oil and the water to generate the separation of liquid phases. For this study, a Computational Fluid Dynamic (CFD) model was developed on STAR-CCM+ software based on 3D geometry of a Franklin Electric 4400 4' four-stage ESP. In this case, the modification of the last stage was carried out to improve the centrifugal effect inside the pump, and a perforated double tube was designed with three different holes configurations disposed at the outlet section, through which the cut water flows. The arrangement of holes used has different geometrical configurations such as circles, rectangles, and irregular shapes determined as grating around the tube. The two-phase flow was modeled using an Eulerian approach with the Volume of Fluid (VOF) method, which predicts the distribution and movement of larger interfaces in immiscible phases. Different water-oil compositions were evaluated, such as 70-30% v/v, 80-20% v/v and 90-10% v/v, respectively. Finally, greater recovery of oil was obtained. For the several compositions evaluated, the volumetric oil fraction was greater than 0.55 at the pump outlet. Similarly, it is possible to show an inversely proportional relationship between the Water/Oil rate (WOR) and the volumetric flow. The volumetric fractions evaluated, the oil flow increased approximately between 41%-10% for circular perforations and 49%-19% for rectangular shaped perforations, regarding the inlet flow. Besides, the elimination of the pump diffuser in the last stage of the pump reduced the head by approximately 20%.

Keywords: computational fluid dynamic, CFD, electrical submersible pump, ESP, two phase flow, volume of fluid, VOF, water/oil rate, WOR

Procedia PDF Downloads 126
131 Main Control Factors of Fluid Loss in Drilling and Completion in Shunbei Oilfield by Unmanned Intervention Algorithm

Authors: Peng Zhang, Lihui Zheng, Xiangchun Wang, Xiaopan Kou

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Quantitative research on the main control factors of lost circulation has few considerations and single data source. Using Unmanned Intervention Algorithm to find the main control factors of lost circulation adopts all measurable parameters. The degree of lost circulation is characterized by the loss rate as the objective function. Geological, engineering and fluid data are used as layers, and 27 factors such as wellhead coordinates and WOB are used as dimensions. Data classification is implemented to determine function independent variables. The mathematical equation of loss rate and 27 influencing factors is established by multiple regression method, and the undetermined coefficient method is used to solve the undetermined coefficient of the equation. Only three factors in t-test are greater than the test value 40, and the F-test value is 96.557%, indicating that the correlation of the model is good. The funnel viscosity, final shear force and drilling time were selected as the main control factors by elimination method, contribution rate method and functional method. The calculated values of the two wells used for verification differ from the actual values by -3.036m3/h and -2.374m3/h, with errors of 7.21% and 6.35%. The influence of engineering factors on the loss rate is greater than that of funnel viscosity and final shear force, and the influence of the three factors is less than that of geological factors. Quantitatively calculate the best combination of funnel viscosity, final shear force and drilling time. The minimum loss rate of lost circulation wells in Shunbei area is 10m3/h. It can be seen that man-made main control factors can only slow down the leakage, but cannot fundamentally eliminate it. This is more in line with the characteristics of karst caves and fractures in Shunbei fault solution oil and gas reservoir.

Keywords: drilling and completion, drilling fluid, lost circulation, loss rate, main controlling factors, unmanned intervention algorithm

Procedia PDF Downloads 75
130 Advancements in Predicting Diabetes Biomarkers: A Machine Learning Epigenetic Approach

Authors: James Ladzekpo

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Background: The urgent need to identify new pharmacological targets for diabetes treatment and prevention has been amplified by the disease's extensive impact on individuals and healthcare systems. A deeper insight into the biological underpinnings of diabetes is crucial for the creation of therapeutic strategies aimed at these biological processes. Current predictive models based on genetic variations fall short of accurately forecasting diabetes. Objectives: Our study aims to pinpoint key epigenetic factors that predispose individuals to diabetes. These factors will inform the development of an advanced predictive model that estimates diabetes risk from genetic profiles, utilizing state-of-the-art statistical and data mining methods. Methodology: We have implemented a recursive feature elimination with cross-validation using the support vector machine (SVM) approach for refined feature selection. Building on this, we developed six machine learning models, including logistic regression, k-Nearest Neighbors (k-NN), Naive Bayes, Random Forest, Gradient Boosting, and Multilayer Perceptron Neural Network, to evaluate their performance. Findings: The Gradient Boosting Classifier excelled, achieving a median recall of 92.17% and outstanding metrics such as area under the receiver operating characteristics curve (AUC) with a median of 68%, alongside median accuracy and precision scores of 76%. Through our machine learning analysis, we identified 31 genes significantly associated with diabetes traits, highlighting their potential as biomarkers and targets for diabetes management strategies. Conclusion: Particularly noteworthy were the Gradient Boosting Classifier and Multilayer Perceptron Neural Network, which demonstrated potential in diabetes outcome prediction. We recommend future investigations to incorporate larger cohorts and a wider array of predictive variables to enhance the models' predictive capabilities.

Keywords: diabetes, machine learning, prediction, biomarkers

Procedia PDF Downloads 16
129 In situ Ortho-Quinone Methide Reactions for Construction of Flavonoids with Fused Ring Systems

Authors: Vidia A. Nuraini, Eugene M. H. Yee, Mohan Bhadbhade, David StC. Black, Naresh Kumar

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Flavonoids are naturally occurring compounds that have been shown to exhibit a wide range of biological properties including anticancer and anti-inflammatory activities. However, flavonoids suffer from low bioavailability, which limits their overall utility for therapeutic applications. One of the methods to overcome this limitation is through structural modification of natural flavonoids. In this study, flavanone, isoflavanone, and isoflavene, were structurally modified through the introduction of additional fused-ring systems via ortho-quinone methide intermediates (o-QMs). These intermediates can readily undergo a [4+2] cycloaddition through an inverse-electron-demand Diels–Alder reaction with electron-rich dienophiles. A regioselective Mannich reaction using bis-(N,N-dimethylamino)methane was employed to generate the o-QM precursors of flavanone, isoflavanone, and isoflavene. The o-QM intermediates were subsequently generated in situ through thermal elimination of the dimethylamine functionality and reacted with a variety of dienophiles to produce novel flavonoids with fused-ring systems. A total of 21 novel flavonoid analogs were successfully synthesized. The X-ray crystal structure of cycloaddition adducts, particularly those derived from 3,4-dihydro-2H-pyran and p-methoxystyrene revealed a special case of enantiomeric disorder, where two enantiomers in equal amounts superpose with one another, with the exception for atoms that have opposite configuration. The anticancer properties of fused-ring systems derived from isoflavene were evaluated against the neuroblastoma SKN-BE(2)C, the triple negative breast cancer MDA-MB-231, and the glioblastoma U87 cancer cell lines. One of these cycloaddition adducts had displayed improved anti-proliferative activity against MDA-MB-231 and U87 cancer cell lines as compared to the parent compound. Further anticancer and anti-inflammatory activities of the flavanone and isoflavanone analogs are currently being investigated.

Keywords: Diels-Alder reaction, flavonoids, Mannich reaction, ortho-quinone methide.

Procedia PDF Downloads 221
128 Evaluation of the Gasification Process for the Generation of Syngas Using Solid Waste at the Autónoma de Colombia University

Authors: Yeraldin Galindo, Soraida Mora

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Solid urban waste represents one of the largest sources of global environmental pollution due to the large quantities of these that are produced every day; thus, the elimination of such waste is a major problem for the environmental authorities who must look for alternatives to reduce the volume of waste with the possibility of obtaining an energy recovery. At the Autónoma de Colombia University, approximately 423.27 kg/d of solid waste are generated mainly paper, cardboard, and plastic. A large amount of these solid wastes has as final disposition the sanitary landfill of the city, wasting the energy potential that these could have, this, added to the emissions generated by the collection and transport of the same, has as consequence the increase of atmospheric pollutants. One of the alternative process used in the last years to generate electrical energy from solid waste such as paper, cardboard, plastic and, mainly, organic waste or biomass to replace the use of fossil fuels is the gasification. This is a thermal conversion process of biomass. The objective of it is to generate a combustible gas as the result of a series of chemical reactions propitiated by the addition of heat and the reaction agents. This project was developed with the intention of giving an energetic use to the waste (paper, cardboard, and plastic) produced inside the university, using them to generate a synthesis gas with a gasifier prototype. The gas produced was evaluated to determine their benefits in terms of electricity generation or raw material for the chemical industry. In this process, air was used as gasifying agent. The characterization of the synthesis gas was carried out by a gas chromatography carried out by the Chemical Engineering Laboratory of the National University of Colombia. Taking into account the results obtained, it was concluded that the gas generated is of acceptable quality in terms of the concentration of its components, but it is a gas of low calorific value. For this reason, the syngas generated in this project is not viable for the production of electrical energy but for the production of methanol transformed by the Fischer-Tropsch cycle.

Keywords: alternative energies, gasification, gasifying agent, solid urban waste, syngas

Procedia PDF Downloads 227
127 Management of Autoimmune Diseases with Ayurveda

Authors: Simmi Chopra

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In the last few years, there has been a surge of Autoimmune diseases that have become more like an epidemic all over the world. The reasons vary from stress, insufficient sleep, smoking, genetics, environmental pollution, adulterated foods, and a diet full of “the deadly white,” which is white sugar and white flour. Most of the people diagnosed with these diseases are given steroids, opioids, supplements, or elimination diets to manage their lives, but most of them continue suffering to varying degrees. On the other hand, Ayurveda can help manage autoimmune problems effectively. Ayurveda is a 5000 years old holistic medical system from India that has an individualistic approach where health problems are looked at from the lens of balancing body and mind and by targeting the root cause of the problem. A combination of diet and lifestyle according to Ayurvedic principles, Ayurvedic herbal formulations and Ayurvedic therapies can help in the management of autoimmune and other chronic diseases. Panchkarma, which is an intense six weeks detox method, helps balance our body and mind, and has been very effective in managing autoimmune problems. The paper will introduce the basic concepts of Ayurveda and describe the terminologies- doshas, agni and ama. The paper will discuss the importance of diet and lifestyle according to the individual’s imbalance in the three functional parameters - doshas, which govern every aspect of our body and mind, our cells and tissues. The significance of agni, which can be correlated to digestive strength and ama, which can be correlated to toxins that are formed in our body leading to health problems, will be outlined. The Ayurvedic pathophysiology of autoimmune diseases will be discussed with emphasis on Rheumatoid arthritis, Multiple sclerosis and Psoriasis. Ayurvedic management will be discussed for these autoimmune conditions. As Ayurveda is an individualistic system, one protocol will not work for everyone. Therefore, case studies with Ayurvedic protocols for the above autoimmune disease will be presented. Conclusion: Ayurveda can help in managing as well as arresting the progression of autoimmune problems. Ayurveda is an ancient medical system, is much more needed today than ever. It is a tried and tested holistic system which has been practiced for the past many generations in India.

Keywords: ayurveda, autoimmune, diseases, nutrition

Procedia PDF Downloads 41
126 Sliding Mode Power System Stabilizer for Synchronous Generator Stability Improvement

Authors: J. Ritonja, R. Brezovnik, M. Petrun, B. Polajžer

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Many modern synchronous generators in power systems are extremely weakly damped. The reasons are cost optimization of the machine building and introduction of the additional control equipment into power systems. Oscillations of the synchronous generators and related stability problems of the power systems are harmful and can lead to failures in operation and to damages. The only useful solution to increase damping of the unwanted oscillations represents the implementation of the power system stabilizers. Power system stabilizers generate the additional control signal which changes synchronous generator field excitation voltage. Modern power system stabilizers are integrated into static excitation systems of the synchronous generators. Available commercial power system stabilizers are based on linear control theory. Due to the nonlinear dynamics of the synchronous generator, current stabilizers do not assure optimal damping of the synchronous generator’s oscillations in the entire operating range. For that reason the use of the robust power system stabilizers which are convenient for the entire operating range is reasonable. There are numerous robust techniques applicable for the power system stabilizers. In this paper the use of sliding mode control for synchronous generator stability improvement is studied. On the basis of the sliding mode theory, the robust power system stabilizer was developed. The main advantages of the sliding mode controller are simple realization of the control algorithm, robustness to parameter variations and elimination of disturbances. The advantage of the proposed sliding mode controller against conventional linear controller was tested for damping of the synchronous generator oscillations in the entire operating range. Obtained results show the improved damping in the entire operating range of the synchronous generator and the increase of the power system stability. The proposed study contributes to the progress in the development of the advanced stabilizer, which will replace conventional linear stabilizers and improve damping of the synchronous generators.

Keywords: control theory, power system stabilizer, robust control, sliding mode control, stability, synchronous generator

Procedia PDF Downloads 199
125 Desulfurization of Crude Oil Using Bacteria

Authors: Namratha Pai, K. Vasantharaj, K. Haribabu

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Our Team is developing an innovative cost effective biological technique to desulfurize crude oil. ’Sulphur’ is found to be present in crude oil samples from .05% - 13.95% and its elimination by industrial methods is expensive currently. Materials required :- Alicyclobacillus acidoterrestrius, potato dextrose agar, oxygen, Pyragallol and inert gas(nitrogen). Method adapted and proposed:- 1) Growth of bacteria studied, energy needs. 2) Compatibility with crude-oil. 3) Reaction rate of bacteria studied and optimized. 4) Reaction development by computer simulation. 5) Simulated work tested by building the reactor. The method being developed requires the use of bacteria Alicyclobacillus acidoterrestrius - an acidothermophilic heterotrophic, soil dwelling aerobic, Sulfur bacteria. The bacteria are fed to crude oil in a unique manner. Its coated onto potato dextrose agar beads, cultured for 24 hours (growth time coincides with time when it begins reacting) and fed into the reactor. The beads are to be replenished with O2 by passing them through a jacket around the reactor which has O2 supply. The O2 can’t be supplied directly as crude oil is inflammable, hence the process. Beads are made to move around based on the concept of fluidized bed reactor. By controlling the velocity of inert gas pumped , the beads are made to settle down when exhausted of O2. It is recycled through the jacket where O2 is re-fed and beads which were inside the ring substitute the exhausted ones. Crude-oil is maintained between 1 atm-270 M Pa pressure and 45°C treated with tartaric acid (Ph reason for bacteria growth) for optimum output. Bacteria being of oxidising type react with Sulphur in crude-oil and liberate out SO4^2- and no gas. SO4^2- is absorbed into H2O. NaOH is fed once reaction is complete and beads separated. Crude-oil is thus separated of SO4^2-, thereby Sulphur, tartaric acid and other acids which are separated out. Bio-corrosion is taken care of by internal wall painting (phenolepoxy paints). Earlier methods used included use of Pseudomonas and Rhodococcus species. They were found to be inefficient, time and energy consuming and reduce the fuel value as they fed on skeleton.

Keywords: alicyclobacillus acidoterrestrius, potato dextrose agar, fluidized bed reactor principle, reaction time for bacteria, compatibility with crude oil

Procedia PDF Downloads 289
124 Pegylated Liposomes of Trans Resveratrol, an Anticancer Agent, for Enhancing Therapeutic Efficacy and Long Circulation

Authors: M. R. Vijayakumar, Sanjay Kumar Singh, Lakshmi, Hithesh Dewangan, Sanjay Singh

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Trans resveratrol (RES) is a natural molecule proved for cancer preventive and therapeutic activities devoid of any potential side effects. However, the therapeutic application of RES in disease management is limited because of its rapid elimination from blood circulation thereby low biological half life in mammals. Therefore, the main objective of this study is to enhance the circulation as well as therapeutic efficacy using PEGylated liposomes. D-α-tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS) is applied as steric surface decorating agent to prepare RES liposomes by thin film hydration method. The prepared nanoparticles were evaluated by various state of the art techniques such as dynamic light scattering (DLS) technique for particle size and zeta potential, TEM for shape, differential scanning calorimetry (DSC) for interaction analysis and XRD for crystalline changes of drug. Encapsulation efficiency and invitro drug release were determined by dialysis bag method. Cancer cell viability studies were performed by MTT assay, respectively. Pharmacokinetic studies were performed in sprague dawley rats. The prepared liposomes were found to be spherical in shape. Particle size and zeta potential of prepared formulations varied from 64.5±3.16 to 262.3±7.45 nm and -2.1 to 1.76 mV, respectively. DSC study revealed absence of potential interaction. XRD study revealed presence of amorphous form in liposomes. Entrapment efficiency was found to be 87.45±2.14 % and the drug release was found to be controlled up to 24 hours. Minimized MEC in MTT assay and tremendous enhancement in circulation time of RES PEGylated liposomes than its pristine form revealed that the stearic stabilized PEGylated liposomes can be an alternative tool to commercialize this molecule for chemopreventive and therapeutic applications in cancer.

Keywords: trans resveratrol, cancer nanotechnology, long circulating liposomes, bioavailability enhancement, liposomes for cancer therapy, PEGylated liposomes

Procedia PDF Downloads 558
123 Effect of Social Stress on Behavioural and Physiological Responses and its Assessment by non-Invasive Method in Zebu Cattle

Authors: Baishali Deb, Hari Om Pandey, Shrilla Elangbam, Mukesh Singh, Ayon Tarafdar, A. K. S. Tomar, A. K. Pandey, Triveni Dutt

Abstract:

The goal of the present investigation was to determine the impact of social stress on behavioural characteristics, physiological responses, and haemato-biochemical indicators under various social environments in Tharparkar cattle. Serum cortisol and faecal cortisol metabolites analysis were used to determine the stress level of Tharparkar cattle. Social isolation and social mixing were the two different social circumstances used to evaluate the animals. In both the experiments i.e., social isolation and social mixing, the lying period of animals decreased significantly (p<0.05) while standing period significantly (p<0.05) increased. Frequency and duration of activities like idling, walking, exploration, oral manipulation, and elimination increased significantly (p<0.05) in Tharparkar cattle after being subjected to social isolation and social mixing. Time spent in grooming (self-grooming and allo-grooming) in respect to social isolation significantly increased during isolation and post-reunion, whereas there was a significant (p<0.05) decline in the grooming behaviour especially allo-grooming during mixing of the animals. Feeding and rumination time also decreased significantly (p<0.05) in animals during both the experiments. Physiological parameters such as respiration rate, heart rate and pulse rate increased during the treatment periods. There was no significant difference in the haematological parameters for both the experiments. There was significant (p<0.05) increase in serum cortisol and faecal cortisol metabolites (FCM) concentration in animals subjected to social stress. Therefore, it can be concluded that social stress strongly impacts the behaviour and physiological parameters of the animals, causing stress and nervousness, proving that social stress is a valid psychological stress in animals. The higher concentration of FCM in Tharparkar cattle subjected to social stress, further supported by higher serum cortisol and behaviour manifestations, suggest that FCM could be used to assess stress response as a non-invasive method.

Keywords: social stress, fecal cortisol metabolites, non-invasive, animal welfare, behaviour

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122 Disaster Management Supported by Unmanned Aerial Systems

Authors: Agoston Restas

Abstract:

Introduction: This paper describes many initiatives and shows also practical examples which happened recently using Unmanned Aerial Systems (UAS) to support disaster management. Since the operation of manned aircraft at disasters is usually not only expensive but often impossible to use as well, in many cases managers fail to use the aerial activity. UAS can be an alternative moreover cost-effective solution for supporting disaster management. Methods: This article uses thematic division of UAS applications; it is based on two key elements, one of them is the time flow of managing disasters, other is its tactical requirements. Logically UAS can be used like pre-disaster activity, activity immediately after the occurrence of a disaster and the activity after the primary disaster elimination. Paper faces different disasters, like dangerous material releases, floods, earthquakes, forest fires and human-induced disasters. Research used function analysis, practical experiments, mathematical formulas, economic analysis and also expert estimation. Author gathered international examples and used own experiences in this field as well. Results and discussion: An earthquake is a rapid escalating disaster, where, many times, there is no other way for a rapid damage assessment than aerial reconnaissance. For special rescue teams, the UAS application can help much in a rapid location selection, where enough place remained to survive for victims. Floods are typical for a slow onset disaster. In contrast, managing floods is a very complex and difficult task. It requires continuous monitoring of dykes, flooded and threatened areas. UAS can help managers largely keeping an area under observation. Forest fires are disasters, where the tactical application of UAS is already well developed. It can be used for fire detection, intervention monitoring and also for post-fire monitoring. In case of nuclear accident or hazardous material leakage, UAS is also a very effective or can be the only one tool for supporting disaster management. Paper shows some efforts using UAS to avoid human-induced disasters in low-income countries as part of health cooperation.

Keywords: disaster management, floods, forest fires, Unmanned Aerial Systems

Procedia PDF Downloads 204
121 Intestacy and Business Continuity among Entrepreneurs in Ondo State, Nigeria

Authors: Igbekoyi Olusola Esther, Olurankinse Felix

Abstract:

This paper examined the factors that militate against Will writing among entrepreneurs in Ondo State Nigeria and the effect of intestate death on business continuity after the exit of the entrepreneurs. The paper was written with a view to providing information on the reasons why intestate death is common among entrepreneurs in Ondo State and the effects on continuity of business after death of the initial owners. Data were obtained from primary source through the administration of questionnaires to entrepreneurs drawn from 50 registered manufacturing companies. These companies have been in existence for a minimum of 10 years with minimum staff strength of 20 workers each. These companies were selected using the purposive random sampling technique in order to capture firms that meet the requirements of this paper. Data obtained were analyzed using descriptive statistics, chi-square and regression analysis. The findings of the paper revealed that administration of Will, traditional beliefs, Will execution procedures, age and non- admissibility of Wills in court are the major factors that militates against Will writing among entrepreneurs in Ondo State. It was also discovered that chaos and instability in business, reduction in sales and productivity, poor succession planning, polygamous nature of marriages, difficulty in sourcing for funds and gender preference are joint predictors of business continuity in event intestate death which is evident in the result where R2 =.954;(F 6, 26)= 89.644; (P < 0.01). The individual beta co-efficient, t- statistics and significance of each variable revealed that gender preference (.735; 7.031; .000) and poor succession plan (.402; 2.840; .009) have significant positive effect on business continuity; while reduction in sales and productivity (-.059; -.335; .740) and difficulty in sourcing for funds (-.217; -1.367; .188) have negative effect; other variables also have positive relationship but they are not significant. It is therefore concluded that business continuity after the exit of the entrepreneur is highly dependent on the rebuilding of confidence on Wills administration in ondo state Nigeria, proper succession planning and elimination of gender preferences.

Keywords: intestacy, business continuity, entrepreneurs, will, succession planning

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120 The Effect of MOOC-Based Distance Education in Academic Engagement and Its Components on Kerman University Students

Authors: Fariba Dortaj, Reza Asadinejad, Akram Dortaj, Atena Baziyar

Abstract:

The aim of this study was to determine the effect of distance education (based on MOOC) on the components of academic engagement of Kerman PNU. The research was quasi-experimental method that cluster sampling with an appropriate volume was used in this study (one class in experimental group and one class in controlling group). Sampling method is single-stage cluster sampling. The statistical society is students of Kerman Payam Noor University, which) were selected 40 of them as sample (20 students in the control group and 20 students in experimental group). To test the hypothesis, it was used the analysis of univariate and Co-covariance to offset the initial difference (difference of control) in the experimental group and the control group. The instrument used in this study is academic engagement questionnaire of Zerang (2012) that contains component of cognitive, behavioral and motivational engagement. The results showed that there is no significant difference between mean scores of academic components of academic engagement in experimental group and the control group on the post-test, after elimination of the pre-test. The adjusted mean scores of components of academic engagement in the experimental group were higher than the adjusted average of scores after the test in the control group. The use of technology-based education in distance education has been effective in increasing cognitive engagement, motivational engagement and behavioral engagement among students. Experimental variable with the effect size 0.26, predicted 26% of cognitive engagement component variance. Experimental variable with the effect size 0.47, predicted 47% of the motivational engagement component variance. Experimental variable with the effect size 0.40, predicted 40% of behavioral engagement component variance. So teaching with technology (MOOC) has a positive impact on increasing academic engagement and academic performance of students in educational technology. The results suggest that technology (MOOC) is used to enrich the teaching of other lessons of PNU.

Keywords: educational technology, distance education, components of academic engagement, mooc technology

Procedia PDF Downloads 115
119 The Impact of International Human Rights Law on Local Efforts to Address Women’s Realities of Violence: Lessons from Jamaica

Authors: Ramona Georgeta Biholar

Abstract:

Gender-based violence against women plagues societies around the world. The work to eliminate it is an ongoing battle. At the international level, Article 5 (a) CEDAW establishes an agenda for social and cultural transformation: it imposes on States parties to CEDAW an obligation to modify sex roles and stereotypical social and cultural patterns of conduct. Also, it provides for the protection of women from violence stemming from such gender norms. Yet, the lived realities of women are frequently disconnected from this agenda. Nonetheless, it is the reality of the local that is crucial for the articulation, implementation and realization of women’s rights in general, and for the elimination of gender-based violence against women in particular. In this paper we discuss the transformation of sex roles and gender stereotyping with a view to realize women’s right to be free from gender-based violence. This paper is anchored in qualitative data collection undertaken in Jamaica and socio-legal research. Based on this research, 1) We explain the process of vernacularisation as a strategy that enables women’s human rights to hit the ground and benefit rights holders, and 2) We present a synergistic model for the implementation of Article 5 (a) CEDAW so that women’s right to be free from gender-based violence can be realized in a concrete national jurisdiction. This model is grounded in context-based demands and recommendations for social and cultural transformation as a remedy for the incidence of gender-based violence against women. Moreover, the synergistic model offers directions that have a general application for the implementation of CEDAW and Article 5 (a) CEDAW in particular, with a view to realize women’s right to be free from gender-based violence. The model is thus not only a conceptual tool of analysis, but also a prescriptive tool for action. It contributes to the work of both academics and practitioners, such as Governmental officials, and national and local civil society representatives. Overall, this paper contributes to understanding the process necessary to bridge that gap between women’s human rights norms and women’s life realities of discrimination and violence.

Keywords: CEDAW, gender-based violence against women, international human rights law, women’s rights implementation, the Caribbean

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118 Principal Component Analysis Combined Machine Learning Techniques on Pharmaceutical Samples by Laser Induced Breakdown Spectroscopy

Authors: Kemal Efe Eseller, Göktuğ Yazici

Abstract:

Laser-induced breakdown spectroscopy (LIBS) is a rapid optical atomic emission spectroscopy which is used for material identification and analysis with the advantages of in-situ analysis, elimination of intensive sample preparation, and micro-destructive properties for the material to be tested. LIBS delivers short pulses of laser beams onto the material in order to create plasma by excitation of the material to a certain threshold. The plasma characteristics, which consist of wavelength value and intensity amplitude, depends on the material and the experiment’s environment. In the present work, medicine samples’ spectrum profiles were obtained via LIBS. Medicine samples’ datasets include two different concentrations for both paracetamol based medicines, namely Aferin and Parafon. The spectrum data of the samples were preprocessed via filling outliers based on quartiles, smoothing spectra to eliminate noise and normalizing both wavelength and intensity axis. Statistical information was obtained and principal component analysis (PCA) was incorporated to both the preprocessed and raw datasets. The machine learning models were set based on two different train-test splits, which were 70% training – 30% test and 80% training – 20% test. Cross-validation was preferred to protect the models against overfitting; thus the sample amount is small. The machine learning results of preprocessed and raw datasets were subjected to comparison for both splits. This is the first time that all supervised machine learning classification algorithms; consisting of Decision Trees, Discriminant, naïve Bayes, Support Vector Machines (SVM), k-NN(k-Nearest Neighbor) Ensemble Learning and Neural Network algorithms; were incorporated to LIBS data of paracetamol based pharmaceutical samples, and their different concentrations on preprocessed and raw dataset in order to observe the effect of preprocessing.

Keywords: machine learning, laser-induced breakdown spectroscopy, medicines, principal component analysis, preprocessing

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117 Urban Ethical Fashion Networks of Design, Production and Retail in Taiwan

Authors: WenYing Claire Shih, Konstantinos Agrafiotis

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The circular economy has become one of the seven fundamental pillars of Taiwan’s economic development, as this is promulgated by the government. The model of the circular economy, with its fundamental premise of waste elimination, can transform the textile and clothing sectors from major pollutant industries to a much cleaner alternative for a better quality of all citizens’ lives. In a related vein, the notion of the creative economy and more specifically the fashion industry can prompt similar results in terms of jobs and wealth creation. The combining forces of the circular and creative economies and their beneficial output have resulted in the configuration of ethical urban networks which potentially may lead to sources of competitive advantage. All actors involved in the configuration of this urban ethical fashion network from public authorities to private enterprise can bring about positive changes in the urban setting. Preliminary results through action research show that this configuration is an attainable task in terms of circularity by reducing fabric waste produced from local textile mills and through innovative methods of design, production and retail around urban spaces where the network has managed to generate a stream of jobs and financial revenues for all participants. The municipal authorities as the facilitating platform have been of paramount importance in this public-private partnership. In the explorative pilot study conducted about a network of production, consumption in terms of circularity of fashion products, we have experienced a positive disposition. As the network will be fully functional by attracting more participant firms from the textile and clothing sectors, it can be beneficial to Taiwan’s soft power in the region and simultaneously elevate citizens’ awareness on circular methods of fashion production, consumption and disposal which can also lead to the betterment of urban lifestyle and may open export horizons for the firms.

Keywords: the circular economy, the creative economy, ethical urban networks, action research

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116 Decommissioning of Nuclear Power Plants: The Current Position and Requirements

Authors: A. Stifi, S. Gentes

Abstract:

Undoubtedly from construction's perspective, the use of explosives will remove a large facility such as a 40-storey building , that took almost 3 to 4 years for construction, in few minutes. Usually, the reconstruction or decommissioning, the last phase of life cycle of any facility, is considered to be the shortest. However, this is proved to be wrong in the case of nuclear power plant. Statistics says that in the last 30 years, the construction of a nuclear power plant took an average time of 6 years whereas it is estimated that decommissioning of such plants may take even a decade or more. This paper is all about the decommissioning phase of a nuclear power plant which needs to be given more attention and encouragement from the research institutes as well as the nuclear industry. Currently, there are 437 nuclear power reactors in operation and 70 reactors in construction. With around 139 nuclear facilities already been shut down and are in different decommissioning stages and approximately 347 nuclear reactors will be in decommissioning phase in the next 20 years (assuming the operation time of a reactor as 40 years), This fact raises the following two questions (1) How far is the nuclear and construction Industry ready to face the challenges of decommissioning project? (2) What is required for a safety and reliable decommissioning project delivery? The decommissioning of nuclear facilities across the global have severe time and budget overruns. Largely the decommissioning processes are being executed by the force of manual labour where the change in regulations is respectively observed. In term of research and development, some research projects and activities are being carried out in this area, but the requirement seems to be much more. The near future of decommissioning shall be better through a sustainable development strategy where all stakeholders agree to implement innovative technologies especially for dismantling and decontamination processes and to deliever a reliable and safety decommissioning. The scope of technology transfer from other industries shall be explored. For example, remotery operated robotic technologies used in automobile and production industry to reduce time and improve effecincy and saftey shall be tried here. However, the innovative technologies are highly requested but they are alone not enough, the implementation of creative and innovative management methodologies should be also investigated and applied. Lean Management with it main concept "elimination of waste within process", is a suitable example here. Thus, the cooperation between international organisations and related industries and the knowledge-sharing may serve as a key factor for the successful decommissioning projects.

Keywords: decommissioning of nuclear facilities, innovative technology, innovative management, sustainable development

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115 Role of Autophagic Lysosome Reformation for Cell Viability in an in vitro Infection Model

Authors: Muhammad Awais Afzal, Lorena Tuchscherr De Hauschopp, Christian Hübner

Abstract:

Introduction: Autophagy is an evolutionarily conserved lysosome-dependent degradation pathway, which can be induced by extrinsic and intrinsic stressors in living systems to adapt to fluctuating environmental conditions. In the context of inflammatory stress, autophagy contributes to the elimination of invading pathogens, the regulation of innate and adaptive immune mechanisms, and regulation of inflammasome activity as well as tissue damage repair. Lysosomes can be recycled from autolysosomes by the process of autophagic lysosome reformation (ALR), which depends on the presence of several proteins including Spatacsin. Thus ALR contributes to the replenishment of lysosomes that are available for fusion with autophagosomes in situations of increased autophagic turnover, e.g., during bacterial infections, inflammatory stress or sepsis. Objectives: We aimed to assess whether ALR plays a role for cell survival in an in-vitro bacterial infection model. Methods: Mouse embryonic fibroblasts (MEFs) were isolated from wild-type mice and Spatacsin (Spg11-/-) knockout mice. Wild-type MEFs and Spg11-/- MEFs were infected with Staphylococcus aureus (multiplication of infection (MOI) used was 10). After 8 and 16 hours of infection, cell viability was assessed on BD flow cytometer through propidium iodide intake. Bacterial intake by cells was also calculated by plating cell lysates on blood agar plates. Results: in-vitro infection of MEFs with Staphylococcus aureus showed a marked decrease of cell viability in ALR deficient Spatacsin knockout (Spg11-/-) MEFs after 16 hours of infection as compared to wild-type MEFs (n=3 independent experiments; p < 0.0001) although no difference was observed for bacterial intake by both genotypes. Conclusion: Suggesting that ALR is important for the defense of invading pathogens e.g. S. aureus, we observed a marked increase of cell death in an in-vitro infection model in cells with compromised ALR.

Keywords: autophagy, autophagic lysosome reformation, bacterial infections, Staphylococcus aureus

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114 Evaluating the Performance of Passive Direct Methanol Fuel Cell under Varying Operating and Structural Conditions

Authors: Rahul Saraswat

Abstract:

More recently, a focus is given on replacing machined stainless steel metal flow-fields with inexpensive wiremesh current collectors. The flow-fields are based on simple woven wiremesh screens of various stainless steels, which are sandwiched between a thin metal plate of the same material to create a bipolar plate/flow-field configuration for use in a stack. Major advantages of using stainless steel wire screens include the elimination of expensive raw materials as well as machining and/or other special fabrication costs. Objective of the project is to improve the performance of the passive direct methanol fuel cell without increasing the cost of the cell and to make it as compact and light as possible. From the literature survey, it was found that very little is done in this direction & the following methodology was used. 1.) The passive DMFC cell can be made more compact, lighter and less costly by changing the material used in its construction. 2.) Controlling the fuel diffusion rate through the cell improves the performance of the cell. A passive liquid feed direct methanol fuel cell ( DMFC ) was fabricated using given MEA( Membrane Electrode Assembly ) and tested for different current collector structure. Mesh current collectors of different mesh densities, along with different support structures, were used, and the performance was found to be better. Methanol concentration was also varied. Optimisation of mesh size, support structure and fuel concentration was achieved. Cost analysis was also performed hereby. From the performance analysis study of DMFC, we can conclude with the following points : Area specific resistance (ASR) of wiremesh current collectors is lower than ASR of stainless steel current collectors. Also, the power produced by wiremesh current collectors is always more than that produced by stainless steel current collectors. Low or moderate methanol concentrations should be used for better and stable DMFC performance. Wiremesh is a good substitute of stainless steel for current collector plates of passive DMFC because of lower cost( by about 27 %), flexibility and light in weight characteristics of wiremesh.

Keywords: direct methanol fuel cell, membrane electrode assembly, mesh, mesh size, methanol concentration and support structure

Procedia PDF Downloads 43
113 Impact of Climate Change on Forest Ecosystem Services: In situ Biodiversity Conservation and Sustainable Management of Forest Resources in Tropical Forests

Authors: Rajendra Kumar Pandey

Abstract:

Forest genetic resources not only represent regional biodiversity but also have immense value as the wealth for securing livelihood of poor people. These are vulnerable to ecological due to depletion/deforestation and /or impact of climate change. These resources of various plant categories are vulnerable on the floor of natural tropical forests, and leading to the threat on the growth and development of future forests. More than 170 species, including NTFPs, are in critical condition for their survival in natural tropical forests of Central India. Forest degradation, commensurate with biodiversity loss, is now pervasive, disproportionately affecting the rural poor who directly depend on forests for their subsistence. Looking ahead the interaction between forest and water, soil, precipitation, climate change, etc. and its impact on biodiversity of tropical forests, it is inevitable to develop co-operation policies and programmes to address new emerging realities. Forests ecosystem also known as the 'wealth of poor' providing goods and ecosystem services on a sustainable basis, are now recognized as a stepping stone to move poor people beyond subsistence. Poverty alleviation is the prime objective of the Millennium Development Goals (MDGs). However, environmental sustainability including other MDGs, is essential to ensure successful elimination of poverty and well being of human society. Loss and degradation of ecosystem are the most serious threats to achieving development goals worldwide. Millennium Ecosystem Assessment (MEA, 2005) was an attempt to identify provisioning and regulating cultural and supporting ecosystem services to provide livelihood security of human beings. Climate change may have a substantial impact on ecological structure and function of forests, provisioning, regulations and management of resources which can affect sustainable flow of ecosystem services. To overcome these limitations, policy guidelines with respect to planning and consistent research strategy need to be framed for conservation and sustainable development of forest genetic resources.

Keywords: climate change, forest ecosystem services, sustainable forest management, biodiversity conservation

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112 Molluscicidal Effect of Cassia occidentalis and Physalis angulata Leaf Extract in the Elimination of Water Snail

Authors: Haruna Karamba, Nafisa Muhammad Danyaro

Abstract:

The study describe the action of natural latex (extract) of two sub-aquatic macrophytes plants i.e., Cassia occidentalis and Physalis angulata which were tested against two water snail species; Bulinus globusus and Lymnaea natalensis, the intermediate host of Bilharziasis (chistosomiasis) in the tropical countries. Bilherziasis is a disease prevalent and endermic to tropical Africa, seriously undermining health status of Nigerian youth. The easiest way to eradicate the disease is to eliminate the secondary host of the pathogen, chistosoma species. Therefore we carried out a research to investigate the molluscicidal effect of the leaf extract of C. occidentalis and P. angulata on mortality rate of B. globusus and L. natalensis water snails using pond water in the laboratory of science laboratory department of Kano State Polytechnic, Nigeria. One hundred and fifty juveniles’ snails were collected from Jakara Dam in the Northeastern part of Kano, Nigeria. The snails were put inside a plastic container and transported immediately to the laboratory where they were transferred into reservoir tank containing pond water and kept for 48 hours to get acclimatized with laboratory environment. Twelve water bathes 2/3 filled with pond water were prepared and kept in the laboratory. Leaf extract of the plants were obtained by blending and homogenizing the leaf tissue from which the extract were obtained and prepared in 10, 20, 30, 40 and 50 ppm, in addition to 0 ppm, which served as control. Ten snails were placed in each of the twelve water bathes. Six water bathes for the species of C. accidentalis extract and other six for P. angulata. The treatment combinations were maintained for 2 days after which the number of living snails present in each water bathes were counted and subsequently at 2 days intervals. The result indicated that extracts from both plants were lethal to the snails as concentration of the extract increases particularly mortality rate was highest at 40 and 50 ppm. Conclusively the toxicity of the extracts from these plants proven lethal to snails and hence can be used as molluscicides for cheap and easy method of eliminating water snails and therefore reducing the incidence of Bilharziasis.

Keywords: schistosomiasis, bilharziasis, Bulinus globusus, Lymnea natalensis, Physalis angulata, Cassia occidentalis, Kano

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111 Formulation and In vivo Evaluation of Venlafaxine Hydrochloride Long Acting Tablet

Authors: Abdulwahhab Khedr, Tamer Shehata, Hanaa El-Ghamry

Abstract:

Venlafaxine HCl is a novel antidepressant drug used in the treatment of major depressive disorder, generalized anxiety disorder, social anxiety disorder and panic disorder. Conventional therapeutic regimens with venlafaxine HCl immediate-release dosage forms require frequent dosing due to short elimination half-life of the drug and reduced bioavailability. Hence, this study was carried out to develop sustained-release dosage forms of venlafaxine HCl to reduce its dosing frequency, to improve patient compliance and to reduce side effects of the drug. The polymers used were hydroxypropylmethyl cellulose, xanthan gum, sodium alginate, sodium carboxymethyl cellulose, Carbopol 940 and ethyl cellulose. The physical properties of the prepared tablets including tablet thickness, diameter, weight uniformity, content uniformity, hardness and friability were evaluated. Also, the in-vitro release of venlafaxine HCl from different matrix tablets was studied. Based on physical characters and in-vitro release profiles, certain formulae showing promising sustained-release profiles were subjected to film coating with 15% w/v EC in dichloromethane/ethanol mixture (1:1 ratio) using 1% w/v HPMC as pore former and 30% w/w dibutyl phthalate as plasticizer. The optimized formulations were investigated for drug-excipient compatibility using FTIR and DSC studies. Physical evaluation of the prepared tablets fulfilled the pharmacopoeial requirements for tablet friability test, where the weight loss of the prepared formulae did not exceed 1% of the weight of the tested tablets. Moderate release was obtained from tablets containing HPMC. FTIR and DSC studies for such formulae revealed the absence of any type of chemical interaction between venlafaxine HCl and the used polymers or excipients. Forced swimming test in rats was used to evaluate the antidepressant activity of the selected matrix tablets of venlafaxine HCl. Results showed that formulations significantly decreased the duration of animals’ immobility during the 24 hr-period of the test compared to non-treated group.

Keywords: antidepressant, sustained-release, matrix tablet, venlafaxine hydrochloride

Procedia PDF Downloads 202
110 Evaluating the Performance of Passive Direct Methanol Fuel Cell under Varying Operating and Structural Conditions

Authors: Rahul Saraswat

Abstract:

More recently, a focus has been given to replacing machined stainless steel metal flow fields with inexpensive wire mesh current collectors. The flow fields are based on simple woven wire mesh screens of various stainless steels, which are sandwiched between a thin metal plate of the same material to create a bipolar plate/flow field configuration for use in a stack. Major advantages of using stainless steel wire screens include the elimination of expensive raw materials as well as machining and/or other special fabrication costs. The objective of the project is to improve the performance of the passive direct methanol fuel cell without increasing the cost of the cell and to make it as compact and light as possible. From the literature survey, it was found that very little is done in this direction, and the following methodology was used. 1. The passive direct methanol fuel cell (DMFC) can be made more compact, lighter, and less costly by changing the material used in its construction. 2. Controlling the fuel diffusion rate through the cell improves the performance of the cell. A passive liquid feed direct methanol fuel cell (DMFC) was fabricated using a given MEA (Membrane Electrode Assembly) and tested for different current collector structures. Mesh current collectors of different mesh densities along with different support structures, were used, and the performance was found to be better. Methanol concentration was also varied. Optimisation of mesh size, support structure, and fuel concentration was achieved. Cost analysis was also performed hereby. From the performance analysis study of DMFC, we can conclude with the following points: Area specific resistance (ASR) of wire mesh current collectors is lower than the ASR of stainless steel current collectors. Also, the power produced by wire mesh current collectors is always more than that produced by stainless steel current collectors. 1. Low or moderate methanol concentrations should be used for better and stable DMFC performance. 2. Wiremesh is a good substitute for stainless steel for current collector plates of passive DMFC because of its lower cost (by about 27 %), flexibility, and light in weight characteristics of wire mesh.

Keywords: direct methanol fuel cell, membrane electrode assembly, mesh, mesh size, methanol concentration, support structure

Procedia PDF Downloads 56