Search results for: drop hammer
131 Re-Evaluating the Hegemony of English Language in West Africa: A Meta-Analysis Review of the Research, 2003-2018
Authors: Oris Tom-Lawyer, Michael Thomas
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This paper seeks to analyse the hegemony of the English language in Western Africa through the lens of educational policies and the socio-economic functions of the language. It is based on the premise that there is a positive link between the English language and development contexts. The study aims to fill a gap in the research literature by examining the usefulness of hegemony as a concept to explain the role of English language in the region, thus countering the negative connotations that often accompany it. The study identified four main research questions: i. What are the socio-economic functions of English in Francophone/lusophone countries? ii. What factors promote the hegemony of English in anglophone countries? iii. To what extent is the hegemony of English in West Africa? iv. What are the implications of the non-hegemony of English in Western Africa? Based on a meta-analysis of the research literature between 2003 and 2018, the findings of the study revealed that in francophone/lusophone countries, English functions in the following socio-economic domains; they are peace keeping missions, regional organisations, commercial and industrial sectors, as an unofficial international language and as a foreign language. The factors that promote linguistic hegemony of English in anglophone countries are English as an official language, a medium of instruction, lingua franca, cultural language, language of politics, language of commerce, channel of development and English for media and entertainment. In addition, the extent of the hegemony of English in West Africa can be viewed from the factors that contribute to the non-hegemony of English in the region; they are French language, Portuguese language, the French culture, neo-colonialism, level of poverty, and economic ties of French to its former colonies. Finally, the implications of the non-hegemony of English language in West Africa are industrial backwardness, poverty rate, lack of social mobility, drop out of school rate, growing interest in English, access to limited internet information and lack of extensive career opportunities. The paper concludes that the hegemony of English has resulted in the development of anglophone countries in Western Africa, while in the francophone/lusophone regions of the continent, industrial backwardness and low literacy rates have been consequences of English language marginalisation. In conclusion, the paper makes several recommendations, including the need for the early introduction of English into French curricula as part of a potential solution.Keywords: developmental tool, English language, linguistic hegemony, West Africa
Procedia PDF Downloads 141130 Simultaneous Detection of Cd⁺², Fe⁺², Co⁺², and Pb⁺² Heavy Metal Ions by Stripping Voltammetry Using Polyvinyl Chloride Modified Glassy Carbon Electrode
Authors: Sai Snehitha Yadavalli, K. Sruthi, Swati Ghosh Acharyya
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Heavy metal ions are toxic to humans and all living species when exposed in large quantities or for long durations. Though Fe acts as a nutrient, when intake is in large quantities, it becomes toxic. These toxic heavy metal ions, when consumed through water, will cause many disorders and are harmful to all flora and fauna through biomagnification. Specifically, humans are prone to innumerable diseases ranging from skin to gastrointestinal, neurological, etc. In higher quantities, they even cause cancer in humans. Detection of these toxic heavy metal ions in water is thus important. Traditionally, the detection of heavy metal ions in water has been done by techniques like Inductively Coupled Plasma Mass Spectroscopy (ICPMS) and Atomic Absorption Spectroscopy (AAS). Though these methods offer accurate quantitative analysis, they require expensive equipment and cannot be used for on-site measurements. Anodic Stripping Voltammetry is a good alternative as the equipment is affordable, and measurements can be made at the river basins or lakes. In the current study, Square Wave Anodic Stripping Voltammetry (SWASV) was used to detect the heavy metal ions in water. Literature reports various electrodes on which deposition of heavy metal ions was carried out like Bismuth, Polymers, etc. The working electrode used in this study is a polyvinyl chloride (PVC) modified glassy carbon electrode (GCE). Ag/AgCl reference electrode and Platinum counter electrode were used. Biologic Potentiostat SP 300 was used for conducting the experiments. Through this work of simultaneous detection, four heavy metal ions were successfully detected at a time. The influence of modifying GCE with PVC was studied in comparison with unmodified GCE. The simultaneous detection of Cd⁺², Fe⁺², Co⁺², Pb⁺² heavy metal ions was done using PVC modified GCE by drop casting 1 wt.% of PVC dissolved in Tetra Hydro Furan (THF) solvent onto GCE. The concentration of all heavy metal ions was 0.2 mg/L, as shown in the figure. The scan rate was 0.1 V/s. Detection parameters like pH, scan rate, temperature, time of deposition, etc., were optimized. It was clearly understood that PVC helped in increasing the sensitivity and selectivity of detection as the current values are higher for PVC-modified GCE compared to unmodified GCE. The peaks were well defined when PVC-modified GCE was used.Keywords: cadmium, cobalt, electrochemical sensing, glassy carbon electrodes, heavy metal Ions, Iron, lead, polyvinyl chloride, potentiostat, square wave anodic stripping voltammetry
Procedia PDF Downloads 103129 The Impact of COVID-19 on Italian Tourism: the Current Scenario, Opportunity and Future Tourism Organizational Strategies
Authors: Marco Camilli
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This article examines the impact of the pandemic outbreak of COVID-19 in the tourism sector in Italy, analyzing the current scenario, the government decisions and the private company reaction for the summer season 2020. The framework of the data analyzed shows how massive it’s the impact of the pandemic outbreak in the tourism revenue, and the weaknesses of the measures proposed. Keywords Travel &Tourism, Transportation, Sustainability, COVID-19, Businesses Introduction The current COVID-19 scenario shows a shocking situation for the tourism and transportation sectors: it could be the most affected by the Coronavirus in Italy. According to forecasts, depending on the duration of the epidemic outbreak and the lockdown strategy applied by the Government, businesses in the supply chain could lose between 24 and 66 billion in turnover in the period of 2020-21, with huge diversified impacts at the national and regional level. Many tourist companies are on the verge of survival and if there are no massive measures by the government they risk closure. Data analysis The tourism and transport sector could be among the sectors most damaged by Covid-19 in Italy. Considering the two-year period 2020-21, companies operating in the travel & tourism sector (Tour operator, Travel Agencies, Hotel, Guides, Bus Company, etc..) could in suffer losses in revenues of 24 to 64 billion euros, especially in the sectors such as the travel agencies, hotel and rental. According to Statista Research Department, from April 2020 estimated that the coronavirus (COVID-19) pandemic will have a significant impact on revenues of the tourism industry in Italy. Revenues are expected to decrease by over 40 billion euros in the first semester of 2020, compared to the same period of the previous year. According to the study, hotel and non-hotel accommodations will experience the highest loss. Revenues of this sector are expected to decrease by 13 billion euros compared to the first semester of 2019 when accommodations registered revenues for about 17 billion euros. According to Statista.com, in 2020, Italy is expected to register a decrease of roughly 28.5 million tourist arrivals due to the impact of coronavirus (COVID-19) on the country's tourist sector. According to the estimate, the region of Veneto will record the highest drop with a decrease of roughly 4.61 million arrivals. Similarly, Lombardy is expected to register a decrease of about 3.87 million arrivals in 2020.Keywords: travel and tourism, sustainability, COVID-19, businesses, transportation
Procedia PDF Downloads 200128 The Gravitational Impact of the Sun and the Moon on Heavy Mineral Deposits and Dust Particles in Low Gravity Regions of the Earth
Authors: T. B. Karu Jayasundara
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The Earth’s gravity is not uniform. The satellite imageries of the Earth’s surface from NASA reveal a number of different gravity anomaly regions all over the globe. When the moon rotates around the earth, its gravity has a major physical influence on a number of regions on the earth. This physical change can be seen by the tides. The tides make sea levels high and low in coastal regions. During high tide, the gravitational force of the Moon pulls the Earth’s gravity so that the total gravitational intensity of Earth is reduced; it is further reduced in the low gravity regions of Earth. This reduction in gravity helps keep the suspended particles such as dust in the atmosphere, sand grains in the sea water for longer. Dramatic differences can be seen from the floating dust in the low gravity regions when compared with other regions. The above phenomena can be demonstrated from experiments. The experiments have to be done in high and low gravity regions of the earth during high and low tide, which will assist in comparing the final results. One of the experiments that can be done is by using a water filled cylinder about 80 cm tall, a few particles, which have the same density and same diameter (about 1 mm) and a stop watch. The selected particles were dropped from the surface of the water in the cylinder and the time taken for the particles to reach the bottom of the cylinder was measured using the stop watch. The times of high and low tide charts can be obtained from the regional government authorities. This concept is demonstrated by the particle drop times taken at high and low tides. The result of the experiment shows that the particle settlement time is less in low tide and high in high tide. The experiment for dust particles in air can be collected on filters, which are cellulose ester membranes and using a vacuum pump. The dust on filters can be used to make slides according to the NOHSC method. Counting the dust particles on the slides can be done using a phase contrast microscope. The results show that the concentration of dust is high at high tide and low in low tide. As a result of the high tides, a high concentration of heavy minerals deposit on placer deposits and dust particles retain in the atmosphere for longer in low gravity regions. These conditions are remarkably exhibited in the lowest low gravity region of the earth, mainly in the regions of India, Sri Lanka and in the middle part of the Indian Ocean. The biggest heavy mineral placer deposits are found in coastal regions of India and Sri Lanka and heavy dust particles are found in the atmosphere of India, particularly in the Delhi region.Keywords: gravity, minerals, tides, moon, costal, atmosphere
Procedia PDF Downloads 128127 The Study of Self-Management of Stress (SMS) of Yoga Program for Pregnant Women in Early Pregnancy in Taiwan
Authors: Shau-Ping Shiu, Shu-Ling Lin
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Pregnancy lead a process of changing in the endocrine system. Either pregnancy itself or the surrounding affect such as the attitude of family to the pregnant lady can bring lots of stress. Sever stress may lead pregnant women display serious mental problem such as mood swings, impulsivity, and abnormal behavior. A method of self management of stress(SMS) has been proved that help patient of cancer in release their stress. This study were going to use SMS to help pregnant women. Methods: In this study, 42 ladies in the first to third months of pregnancy process applied to join SMS of program have divided into 21 participants in both control and experimental group by draw. 24 sessions of Yoga program were conducted once a week for 6 months for experimental group. Verbatim used to gather more feedbacks from the interview followed by each Yoga sessions. Brief symptom Rating scale also conducted pre and post experiment for 42 participations. Results: Overall score of Brief Symptom Rating Scale reduced 17.82 points and suicide drop 9 points in experimental group, compared to the control group increasing 10.24 point of overall score and suicide add 7 points. Feedback from interviews showed participations improved in emotion, physical health and stress management. They indicated having more positive emotion daily, having better gastrointestinal peristalsis movement, releasing back tention, well weight control, reducing stress and changing the quality of interpersonal relationships. Conclusion: SMS of Yoga program in this study included four key training directions which were stimulation, relaxation, awareness and pranayama lead a great improvment of stress management for pregnant lady. Throughout this Yoga program, women learned to ignite eustress, remove distress, create calmness and breath slows down. As the result, Yoga program has helped women in experiment group lower their tension, and bring the extra benifits in emotion and relationships. It support women to overcome their pregnancy. Suggestion: An unexpected result of this study showed all participants had no morning sickness since they engaged in SMS program, and no one absent from course due to the benefits of it. We strongly suggest that SMS of Yoga program can be a add of medication for women in pregnancy, however, the position of Forward in the SMS sequence has been point out pressing participant’s stomach, which can be replace to Bridge position to comfort participants.Keywords: self-management of stress(SMS), yoga program, pregnant women, early pregnancy
Procedia PDF Downloads 330126 The Influence of Morphology and Interface Treatment on Organic 6,13-bis (triisopropylsilylethynyl)-Pentacene Field-Effect Transistors
Authors: Daniel Bülz, Franziska Lüttich, Sreetama Banerjee, Georgeta Salvan, Dietrich R. T. Zahn
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For the development of electronics, organic semiconductors are of great interest due to their adjustable optical and electrical properties. Especially for spintronic applications they are interesting because of their weak spin scattering, which leads to longer spin life times compared to inorganic semiconductors. It was shown that some organic materials change their resistance if an external magnetic field is applied. Pentacene is one of the materials which exhibit the so called photoinduced magnetoresistance which results in a modulation of photocurrent when varying the external magnetic field. Also the soluble derivate of pentacene, the 6,13-bis (triisopropylsilylethynyl)-pentacene (TIPS-pentacene) exhibits the same negative magnetoresistance. Aiming for simpler fabrication processes, in this work, we compare TIPS-pentacene organic field effect transistors (OFETs) made from solution with those fabricated by thermal evaporation. Because of the different processing, the TIPS-pentacene thin films exhibit different morphologies in terms of crystal size and homogeneity of the substrate coverage. On the other hand, the interface treatment is known to have a high influence on the threshold voltage, eliminating trap states of silicon oxide at the gate electrode and thereby changing the electrical switching response of the transistors. Therefore, we investigate the influence of interface treatment using octadecyltrichlorosilane (OTS) or using a simple cleaning procedure with acetone, ethanol, and deionized water. The transistors consist of a prestructured OFET substrates including gate, source, and drain electrodes, on top of which TIPS-pentacene dissolved in a mixture of tetralin and toluene is deposited by drop-, spray-, and spin-coating. Thereafter we keep the sample for one hour at a temperature of 60 °C. For the transistor fabrication by thermal evaporation the prestructured OFET substrates are also kept at a temperature of 60 °C during deposition with a rate of 0.3 nm/min and at a pressure below 10-6 mbar. The OFETs are characterized by means of optical microscopy in order to determine the overall quality of the sample, i.e. crystal size and coverage of the channel region. The output and transfer characteristics are measured in the dark and under illumination provided by a white light LED in the spectral range from 450 nm to 650 nm with a power density of (8±2) mW/cm2.Keywords: organic field effect transistors, solution processed, surface treatment, TIPS-pentacene
Procedia PDF Downloads 447125 MicroRNA Drivers of Resistance to Androgen Deprivation Therapy in Prostate Cancer
Authors: Philippa Saunders, Claire Fletcher
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INTRODUCTION: Prostate cancer is the most prevalent malignancy affecting Western males. It is initially an androgen-dependent disease: androgens bind to the androgen receptor and drive the expression of genes that promote proliferation and evasion of apoptosis. Despite reduced androgen dependence in advanced prostate cancer, androgen receptor signaling remains a key driver of growth. Androgen deprivation therapy (ADT) is, therefore, a first-line treatment approach and works well initially, but resistance inevitably develops. Abiraterone and Enzalutamide are drugs widely used in ADT and are androgen synthesis and androgen receptor signaling inhibitors, respectively. The shortage of other treatment options means acquired resistance to these drugs is a major clinical problem. MicroRNAs (miRs) are important mediators of post-transcriptional gene regulation and show altered expression in cancer. Several have been linked to the development of resistance to ADT. Manipulation of such miRs may be a pathway to breakthrough treatments for advanced prostate cancer. This study aimed to validate ADT resistance-implicated miRs and their clinically relevant targets. MATERIAL AND METHOD: Small RNA-sequencing of Abiraterone- and Enzalutamide-resistant C42 prostate cancer cells identified subsets of miRs dysregulated as compared to parental cells. Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) was used to validate altered expression of candidate ADT resistance-implicated miRs 195-5p, 497-5p and 29a-5p in ADT-resistant and -responsive prostate cancer cell lines, patient-derived xenografts (PDXs) and primary prostate cancer explants. RESULTS AND DISCUSSION: This study suggests a possible role for miR-497-5p in the development of ADT resistance in prostate cancer. MiR-497-5p expression was increased in ADT-resistant versus ADT-responsive prostate cancer cells. Importantly, miR-497-5p expression was also increased in Enzalutamide-treated, castrated (ADT-mimicking) PDXs versus intact PDXs. MiR-195-5p was also elevated in ADT-resistant versus -responsive prostate cancer cells, while there was a drop in miR-29a-5p expression. Candidate clinically relevant targets of miR-497-5p in prostate cancer were identified by mining AGO-PAR-CLIP-seq data sets and may include AVL9 and FZD6. CONCLUSION: In summary, this study identified microRNAs that are implicated in prostate cancer resistance to androgen deprivation therapy and could represent novel therapeutic targets for advanced disease.Keywords: microRNA, androgen deprivation therapy, Enzalutamide, abiraterone, patient-derived xenograft
Procedia PDF Downloads 143124 Experimental Investigation of Cutting Forces and Temperature in Bone Drilling
Authors: Vishwanath Mali, Hemant Warhatkar, Raju Pawade
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Drilling of bone has been always challenging for surgeons due to the adverse effect it may impart to bone tissues. Force has to be applied manually by the surgeon while performing conventional bone drilling which may lead to permanent death of bone tissues and nerves. During bone drilling the temperature of the bone tissues increases to higher values above 47 ⁰C that causes thermal osteonecrosis resulting into screw loosening and subsequent implant failures. An attempt has been made here to study the input drilling parameters and surgical drill bit geometry affecting bone health during bone drilling. A One Factor At a Time (OFAT) method is used to plan the experiments. Input drilling parameters studied include spindle speed and feed rate. The drill bit geometry parameter studied include point angle and helix angle. The output variables are drilling thrust force and bone temperature. The experiments were conducted on goat femur bone at room temperature 30 ⁰C. For measurement of thrust forces KISTLER cutting force dynamometer Type 9257BA was used. For continuous data acquisition of temperature NI LabVIEW software was used. Fixture was made on RPT machine for holding the bone specimen while performing drilling operation. Bone specimen were preserved in deep freezer (LABTOP make) under -40 ⁰C. In case of drilling parameters, it is observed that at constant feed rate when spindle speed increases, thrust force as well as temperature decreases and at constant spindle speed when feed rate increases thrust force as well as temperature increases. The effect of drill bit geometry shows that at constant helix angle when point angle increases thrust force as well as temperature increases and at constant point angle when helix angle increase thrust force as well as temperature decreases. Hence it is concluded that as the thrust force increases temperature increases. In case of drilling parameter, the lowest thrust force and temperature i.e. 35.55 N and 36.04 ⁰C respectively were recorded at spindle speed 2000 rpm and feed rate 0.04 mm/rev. In case of drill bit geometry parameter, the lowest thrust force and temperature i.e. 40.81 N and 34 ⁰C respectively were recorded at point angle 70⁰ and helix angle 25⁰ Hence to avoid thermal necrosis of bone it is recommended to use higher spindle speed, lower feed rate, low point angle and high helix angle. The hard nature of cortical bone contributes to a greater rise in temperature whereas a considerable drop in temperature is observed during cancellous bone drilling.Keywords: bone drilling, helix angle, point angle, thrust force, temperature, thermal necrosis
Procedia PDF Downloads 309123 Winkler Springs for Embedded Beams Subjected to S-Waves
Authors: Franco Primo Soffietti, Diego Fernando Turello, Federico Pinto
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Shear waves that propagate through the ground impose deformations that must be taken into account in the design and assessment of buried longitudinal structures such as tunnels, pipelines, and piles. Conventional engineering approaches for seismic evaluation often rely on a Euler-Bernoulli beam models supported by a Winkler foundation. This approach, however, falls short in capturing the distortions induced when the structure is subjected to shear waves. To overcome these limitations, in the present work an analytical solution is proposed considering a Timoshenko beam and including transverse and rotational springs. The present research proposes ground springs derived as closed-form analytical solutions of the equations of elasticity including the seismic wavelength. These proposed springs extend the applicability of previous plane-strain models. By considering variations in displacements along the longitudinal direction, the presented approach ensures the springs do not approach zero at low frequencies. This characteristic makes them suitable for assessing pseudo-static cases, which typically govern structural forces in kinematic interaction analyses. The results obtained, validated against existing literature and a 3D Finite Element model, reveal several key insights: i) the cutoff frequency significantly influences transverse and rotational springs; ii) neglecting displacement variations along the structure axis (i.e., assuming plane-strain deformation) results in unrealistically low transverse springs, particularly for wavelengths shorter than the structure length; iii) disregarding lateral displacement components in rotational springs and neglecting variations along the structure axis leads to inaccurately low spring values, misrepresenting interaction phenomena; iv) transverse springs exhibit a notable drop in resonance frequency, followed by increasing damping as frequency rises; v) rotational springs show minor frequency-dependent variations, with radiation damping occurring beyond resonance frequencies, starting from negative values. This comprehensive analysis sheds light on the complex behavior of embedded longitudinal structures when subjected to shear waves and provides valuable insights for the seismic assessment.Keywords: shear waves, Timoshenko beams, Winkler springs, sol-structure interaction
Procedia PDF Downloads 61122 Hansen Solubility Parameter from Surface Measurements
Authors: Neveen AlQasas, Daniel Johnson
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Membranes for water treatment are an established technology that attracts great attention due to its simplicity and cost effectiveness. However, membranes in operation suffer from the adverse effect of membrane fouling. Bio-fouling is a phenomenon that occurs at the water-membrane interface, and is a dynamic process that is initiated by the adsorption of dissolved organic material, including biomacromolecules, on the membrane surface. After initiation, attachment of microorganisms occurs, followed by biofilm growth. The biofilm blocks the pores of the membrane and consequently results in reducing the water flux. Moreover, the presence of a fouling layer can have a substantial impact on the membrane separation properties. Understanding the mechanism of the initiation phase of biofouling is a key point in eliminating the biofouling on membrane surfaces. The adhesion and attachment of different fouling materials is affected by the surface properties of the membrane materials. Therefore, surface properties of different polymeric materials had been studied in terms of their surface energies and Hansen solubility parameters (HSP). The difference between the combined HSP parameters (HSP distance) allows prediction of the affinity of two materials to each other. The possibilities of measuring the HSP of different polymer films via surface measurements, such as contact angle has been thoroughly investigated. Knowing the HSP of a membrane material and the HSP of a specific foulant, facilitate the estimation of the HSP distance between the two, and therefore the strength of attachment to the surface. Contact angle measurements using fourteen different solvents on five different polymeric films were carried out using the sessile drop method. Solvents were ranked as good or bad solvents using different ranking method and ranking was used to calculate the HSP of each polymeric film. Results clearly indicate the absence of a direct relation between contact angle values of each film and the HSP distance between each polymer film and the solvents used. Therefore, estimating HSP via contact angle alone is not sufficient. However, it was found if the surface tensions and viscosities of the used solvents are taken in to the account in the analysis of the contact angle values, a prediction of the HSP from contact angle measurements is possible. This was carried out via training of a neural network model. The trained neural network model has three inputs, contact angle value, surface tension and viscosity of solvent used. The model is able to predict the HSP distance between the used solvent and the tested polymer (material). The HSP distance prediction is further used to estimate the total and individual HSP parameters of each tested material. The results showed an accuracy of about 90% for all the five studied filmsKeywords: surface characterization, hansen solubility parameter estimation, contact angle measurements, artificial neural network model, surface measurements
Procedia PDF Downloads 94121 A Comparison of Direct Water Injection with Membrane Humidifier for Proton Exchange Membrane Fuel Cells Humification
Authors: Flavien Marteau, Pedro Affonso Nóbrega, Pascal Biwole, Nicolas Autrusson, Iona De Bievre, Christian Beauger
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Effective water management is essential for the optimal performance of fuel cells. For this reason, many vehicle systems use a membrane humidifier, a passive device that humidifies the air before the cathode inlet. Although they offer good performance, humidifiers are voluminous, costly, and fragile, hence the desire to find an alternative. Direct water injection could be an option, although this method lacks maturity. It consists of injecting liquid water as a spray in the dry heated air coming out from the compressor. This work focuses on the evaluation of direct water injection and its performance compared to the membrane humidifier selected as a reference. Two architectures were experimentally tested to humidify an industrial 2 kW short stack made up of 20 cells of 150 cm² each. For the reference architecture, the inlet air is humidified with a commercial membrane humidifier. For the direct water injection architecture, a pneumatic nozzle was selected to generate a fine spray in the air flow with a Sauter mean diameter of about 20 μm. Initial performance was compared over the entire range of current based on polarisation curves. Then, the influence of various parameters impacting water management was studied, such as the temperature, the gas stoichiometry, and the water injection flow rate. The experimental results obtained confirm the possibility of humidifying the fuel cell using direct water injection. This study, however shows the limits of this humidification method, the mean cell voltage being significantly lower in some operating conditions with direct water injection than with the membrane humidifier. The voltage drop reaches 30 mV per cell (4 %) at 1 A/cm² (1,8 bara, 80 °C) and increases in more demanding humidification conditions. It is noteworthy that the heat of compression available is not enough to evaporate all the injected liquid water in the case of DWI, resulting in a mix of liquid and vapour water entering the fuel cell, whereas only vapour is present with the humidifier. Variation of the injection flow rate shows that part of the injected water is useless for humidification and seems to cross channels without reaching the membrane. The stack was successfully humidified thanks to direct water injection. Nevertheless, our work shows that its implementation requires substantial adaptations and may reduce the fuel cell stack performance when compared to conventional membrane humidifiers, but opportunities for optimisation have been identified.Keywords: cathode humidification, direct water injection, membrane humidifier, proton exchange membrane fuel cell
Procedia PDF Downloads 43120 Characterization of a Lipolytic Enzyme of Pseudomonas nitroreducens Isolated from Mealworm's Gut
Authors: Jung-En Kuan, Whei-Fen Wu
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In this study, a symbiotic bacteria from yellow mealworm's (Tenebrio molitor) mid-gut was isolated with characteristics of growth on minimal-tributyrin medium. After a PCR-amplification of its 16s rDNA, the resultant nucleotide sequences were then analyzed by schemes of the phylogeny trees. Accordingly, it was designated as Pseudomonas nitroreducens D-01. Next, by searching the lipolytic enzymes in its protein data bank, one of those potential lipolytic α/β hydrolases was identified, again using PCR-amplification and nucleotide-sequencing methods. To construct an expression of this lipolytic gene in plasmids, the target-gene primers were then designed, carrying the C-terminal his-tag sequences. Using the vector pET21a, a recombinant lipolytic hydrolase D gene with his-tag nucleotides was successfully cloned into it, of which the lipolytic D gene is under a control of the T7 promoter. After transformation of the resultant plasmids into Eescherichia coli BL21 (DE3), an IPTG inducer was used for the induction of the recombinant proteins. The protein products were then purified by metal-ion affinity column, and the purified proteins were found capable of forming a clear zone on tributyrin agar plate. Shortly, its enzyme activities were determined by degradation of p-nitrophenyl ester(s), and the substantial yellow end-product, p-nitrophenol, was measured at O.D.405 nm. Specifically, this lipolytic enzyme efficiently targets p-nitrophenyl butyrate. As well, it shows the most reactive activities at 40°C, pH 8 in potassium phosphate buffer. In thermal stability assays, the activities of this enzyme dramatically drop when the temperature is above 50°C. In metal ion assays, MgCl₂ and NH₄Cl induce the enzyme activities while MnSO₄, NiSO₄, CaCl₂, ZnSO₄, CoCl₂, CuSO₄, FeSO₄, and FeCl₃ reduce its activities. Besides, NaCl has no effects on its enzyme activities. Most organic solvents decrease the activities of this enzyme, such as hexane, methanol, ethanol, acetone, isopropanol, chloroform, and ethyl acetate. However, its enzyme activities increase when DMSO exists. All the surfactants like Triton X-100, Tween 80, Tween 20, and Brij35 decrease its lipolytic activities. Using Lineweaver-Burk double reciprocal methods, the function of the enzyme kinetics were determined such as Km = 0.488 (mM), Vmax = 0.0644 (mM/min), and kcat = 3.01x10³ (s⁻¹), as well the total efficiency of kcat/Km is 6.17 x10³ (mM⁻¹/s⁻¹). Afterwards, based on the phylogenetic analyses, this lipolytic protein is classified to type IV lipase by its homologous conserved region in this lipase family.Keywords: enzyme, esterase, lipotic hydrolase, type IV
Procedia PDF Downloads 133119 Clean Sky 2 – Project PALACE: Aeration’s Experimental Sound Velocity Investigations for High-Speed Gerotor Simulations
Authors: Benoît Mary, Thibaut Gras, Gaëtan Fagot, Yvon Goth, Ilyes Mnassri-Cetim
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A Gerotor pump is composed of an external and internal gear with conjugate cycloidal profiles. From suction to delivery ports, the fluid is transported inside cavities formed by teeth and driven by the shaft. From a geometric and conceptional side it is worth to note that the internal gear has one tooth less than the external one. Simcenter Amesim v.16 includes a new submodel for modelling the hydraulic Gerotor pumps behavior (THCDGP0). This submodel considers leakages between teeth tips using Poiseuille and Couette flows contributions. From the 3D CAD model of the studied pump, the “CAD import” tool takes out the main geometrical characteristics and the submodel THCDGP0 computes the evolution of each cavity volume and their relative position according to the suction or delivery areas. This module, based on international publications, presents robust results up to 6 000 rpm for pressure greater than atmospheric level. For higher rotational speeds or lower pressures, oil aeration and cavitation effects are significant and highly drop the pump’s performance. The liquid used in hydraulic systems always contains some gas, which is dissolved in the liquid at high pressure and tends to be released in a free form (i.e. undissolved as bubbles) when pressure drops. In addition to gas release and dissolution, the liquid itself may vaporize due to cavitation. To model the relative density of the equivalent fluid, modified Henry’s law is applied in Simcenter Amesim v.16 to predict the fraction of undissolved gas or vapor. Three parietal pressure sensors have been set up upstream from the pump to estimate the sound speed in the oil. Analytical models have been compared with the experimental sound speed to estimate the occluded gas content. Simcenter Amesim v.16 model was supplied by these previous analyses marks which have successfully improved the simulations results up to 14 000 rpm. This work provides a sound foundation for designing the next Gerotor pump generation reaching high rotation range more than 25 000 rpm. This improved module results will be compared to tests on this new pump demonstrator.Keywords: gerotor pump, high speed, numerical simulations, aeronautic, aeration, cavitation
Procedia PDF Downloads 133118 Durham Region: How to Achieve Zero Waste in a Municipal Setting
Authors: Mirka Januszkiewicz
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The Regional Municipality of Durham is the upper level of a two-tier municipal and regional structure comprised of eight lower-tier municipalities. With a population of 655,000 in both urban and rural settings, the Region is approximately 2,537 square kilometers neighboring the City of Toronto, Ontario Canada to the east. The Region has been focused on diverting waste from disposal since the development of its Long Term Waste Management Strategy Plan for 2000-2020. With a 54 percent solid waste diversion rate, the focus now is on achieving 70 percent diversion on the path to zero waste using local waste management options whenever feasible. The Region has an Integrated Waste Management System that consists of a weekly curbside collection of recyclable printed paper and packaging and source separated organics; a seasonal collection of leaf and yard waste; a bi-weekly collection of residual garbage; and twice annual collection of intact, sealed household batteries. The Region also maintains three Waste Management Facilities for residential drop-off of household hazardous waste, polystyrene, construction and demolition debris and electronics. Special collection events are scheduled in the spring, summer and fall months for reusable items, household hazardous waste, and electronics. The Region is in the final commissioning stages of an energy from the waste facility for residual waste disposal that will recover energy from non-recyclable wastes. This facility is state of the art and is equipped for installation of carbon capture technology in the future. Despite all of these diversion programs and efforts, there is still room for improvement. Recent residential waste studies revealed that over 50% of the residual waste placed at the curb that is destined for incineration could be recycled. To move towards a zero waste community, the Region is looking to more advanced technologies for extracting the maximum recycling value from residential waste. Plans are underway to develop a pre-sort facility to remove organics and recyclables from the residual waste stream, including the growing multi-residential sector. Organics would then be treated anaerobically to generate biogas and fertilizer products for beneficial use within the Region. This project could increase the Region’s diversion rate beyond 70 percent and enhance the Region’s climate change mitigation goals. Zero waste is an ambitious goal in a changing regulatory and economic environment. Decision makers must be willing to consider new and emerging technologies and embrace change to succeed.Keywords: municipal waste, residential, waste diversion, zero waste
Procedia PDF Downloads 219117 Whey Protein: A Noval Protective Agent against Oto-Toxicity Induced by Cis-Platin in Male Rat
Authors: Eitedal Daoud, Reda M.Daoud, Khaled Abdel-Wahhab, Maha M.Saber, Lobna Saber
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Background: Cis-platin is a widely used chemotherapeutic drug to treat many malignant disorders including head and neck malignancies. Oto-nephrotxicity is an important and dose - limiting side effect of cis - platin therapy. Nowadays, more attention had been paid to oto-toxicity caused with cis-platin. Aim of the Work: This study was designed to investigate the potential protective effect of Whey protein (WP) against cis-platin induced ototoxicity compared to the effect of N-acetylcysteine (NAC) in rats. Methodology: Male albino rats were randomly divided into 6 groups: untreated rats (control), rats orally treated with whey protein (1g/kg b.w/day) for seven executive days, rats treated orally with N-acetylcysteine (500 mg/kgb.w /day) for seven executive days, rates intoxicated intraperitoneal (ip) with cis- platin (10 mg/kgb.w. once), rats treated with whey protein (1g/kgb.w./day) for seven executive days) followed by one injection (ip) of cis-platin(10 mg/kg b.w.) one hour after the last oral administration of whey protein, rats treated with N- acetylcysteine (for seven executive days followed by one injection (ip) of cis-platin (10 mg/kgb.w) one hour after the last oral administration of N-acetylcysteine. The organ of Corti, the stria vascularis and spiral ganglia were visualized by light microscopy at different magnifications. Results: Cis-platin intoxicated animals showed a significant decrease in serum level of total antioxidant capacity (TAC),with inhibition in the activity of serum glutathione-s transferase(GST) and paraoxonnase-1 (PON-1) in comparison with control. Group treated with either NAC or WP with cis-platin showed significant elevation in the activity of both GST & PON-1 with increased serum level of TAC when compared with cis-platin intoxicated rats. Animals treated with NAC or WP with cis-platin compared to those treated with cis-platin alone showed marked degree of improvement towards control rats as there was significant drop in the serum level of cortecosterone, nitric oxide (NO), and melandialdehyde (MDA).Histopathologic, in NAC pretreated group there was no changes in stria vascularis or spiral ganglia. In group pretreated with WP, there was no histopathologic alteration detected in the organ of Corti and Reissers membrane but oedema and haemorrhage were founded in the stria vascularis in small focal manner. Conclusion: Our finding showed that Whey protein is a natural dietary supplement product proved its ability of protection of anti-oxidant system and the cochlea against cis-platin induced ototoxicity.Keywords: anti-oxidant, cis-platin, N-acetylcysteine, ototoxicity, whey protein
Procedia PDF Downloads 523116 Effects of Bleaching Procedures on Dentine Sensitivity
Authors: Suhayla Reda Al-Banai
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Problem Statement: Tooth whitening was used for over one hundred and fifty year. The question concerning the whiteness of teeth is a complex one since tooth whiteness will vary from individual to individual, dependent on age and culture, etc. Tooth whitening following treatment may be dependent on the type of whitening system used to whiten the teeth. There are a few side-effects to the process, and these include tooth sensitivity and gingival irritation. Some individuals may experience no pain or sensitivity following the procedure. Purpose: To systematically review the available published literature until 31st December 2021 to identify all relevant studies for inclusion and to determine whether there was any evidence demonstrating that the application of whitening procedures resulted in the tooth sensitivity. Aim: Systematically review the available published works of literature to identify all relevant studies for inclusion and to determine any evidence demonstrating that application of 10% & 15% carbamide peroxide in tooth whitening procedures resulted in tooth sensitivity. Material and Methods: Following a review of 70 relevant papers from searching both electronic databases (OVID MEDLINE and PUBMED) and hand searching of relevant written journals, 49 studies were identified, 42 papers were subsequently excluded, and 7 studies were finally accepted for inclusion. The extraction of data for inclusion was conducted by two reviewers. The main outcome measures were the methodology and assessment used by investigators to evaluate tooth sensitivity in tooth whitening studies. Results: The reported evaluation of tooth sensitivity during tooth whitening procedures was based on the subjective response of subjects rather than a recognized methodology for evaluating. One of the problems in evaluating was the lack of homogeneity in study design. Seven studies were included. The studies included essential features namely: randomized group, placebo controls, doubleblind and single-blind. Drop-out was obtained from two of included studies. Three of the included studies reported sensitivity at the baseline visit. Two of the included studies mentioned the exclusion criteria Conclusions: The results were inconclusive due to: Limited number of included studies, the study methodology, and evaluation of DS reported. Tooth whitening procedures adversely affect both hard and soft tissues in the oral cavity. Sideeffects are mild and transient in nature. Whitening solutions with greater than 10% carbamide peroxide causes more tooth sensitivity. Studies using nightguard vital bleaching with 10% carbamide peroxide reported two side effects tooth sensitivity and gingival irritation, although tooth sensitivity was more prevalent than gingival irritationKeywords: dentine, sensitivity, bleaching, carbamide peroxde
Procedia PDF Downloads 70115 Applying Sociometer Theory to Different Age Groups and Groups Differences regarding State Self-Esteem Sensitivity
Authors: Yun Yu Stephanie Law
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Sociometer Theory is well tested among young adults in western population, however, limited research is found for other age groups, like adolescent and middle-adulthood in Asia population. Thus, one of the main purposes of this study is to verify the validity of Sociometer Theory in different age groups among Asian. To be specific, we hypothesized that an increase in one’s perceived social rejection is associated to a decrease in his/her state self-esteem among all age groups in Asian population. And we expected that this association can be found among all age groups including adolescent, young adults and middle-adults group in our first study. In this way, we can verify the validity of Sociometer Theory across different age groups as well as its significance in Asian population. Furthermore, those participants who received rejection about ‘mate-role’ would also receive some negative feedbacks regarding their current/future capacity of being a good mate. Results suggested that participants’ state self-esteem sensitivity for mating-capacity rejection is higher when comparing to that of friend-capacity rejection, i.e. greater drop in state self-esteem when receiving mating-capacity feedbacks then receiving friend-capacity feedbacks. These results, however, is just applicable on young adults. Thus, the main purpose of study two would be testing the state self-esteem sensitivity towards social rejection in different domains among three age groups. We hypothesized that group differences would be found for three age groups regarding state self-esteem sensitivity. Research question 1: perceived social rejection is associated to decrease in state self-esteem, is applicable among different age groups in Asia population. Research question 2: there are significant group differences for three age groups regarding state self-esteem sensitivity. Methods: 300 subjects are divided into three age groups, adolescents group, young adult group and middle-adult group, with 100 subjects in each group. Two questionnaires were used in testing this fundamental concept. Subjects were then asked to rate themselves on questionnaire in measuring their current state self-esteem in order to obtain the baseline measurements for later comparison. In order to avoid demand characteristics from subjects, other unrelated tasks like word matching were also given after the first test. Results: A positive correlation between scores in questionnaire 1 and questionnaire 2 among all age groups. Conclusion: State self-esteem decrease to both imagined social rejection (study1) and experienced social rejection (study2). Moreover, level of decrease in state self-esteem vary when receiving different domains of social rejection. Implications: a better understanding of self-esteem development for various age group might bring insights for education systems and policies for teaching approaches and learning methods among different age groups.Keywords: state self-esteem, social rejection, stage theory, self-feelings
Procedia PDF Downloads 230114 Systematic Evaluation of Convolutional Neural Network on Land Cover Classification from Remotely Sensed Images
Authors: Eiman Kattan, Hong Wei
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In using Convolutional Neural Network (CNN) for classification, there is a set of hyperparameters available for the configuration purpose. This study aims to evaluate the impact of a range of parameters in CNN architecture i.e. AlexNet on land cover classification based on four remotely sensed datasets. The evaluation tests the influence of a set of hyperparameters on the classification performance. The parameters concerned are epoch values, batch size, and convolutional filter size against input image size. Thus, a set of experiments were conducted to specify the effectiveness of the selected parameters using two implementing approaches, named pertained and fine-tuned. We first explore the number of epochs under several selected batch size values (32, 64, 128 and 200). The impact of kernel size of convolutional filters (1, 3, 5, 7, 10, 15, 20, 25 and 30) was evaluated against the image size under testing (64, 96, 128, 180 and 224), which gave us insight of the relationship between the size of convolutional filters and image size. To generalise the validation, four remote sensing datasets, AID, RSD, UCMerced and RSCCN, which have different land covers and are publicly available, were used in the experiments. These datasets have a wide diversity of input data, such as number of classes, amount of labelled data, and texture patterns. A specifically designed interactive deep learning GPU training platform for image classification (Nvidia Digit) was employed in the experiments. It has shown efficiency in both training and testing. The results have shown that increasing the number of epochs leads to a higher accuracy rate, as expected. However, the convergence state is highly related to datasets. For the batch size evaluation, it has shown that a larger batch size slightly decreases the classification accuracy compared to a small batch size. For example, selecting the value 32 as the batch size on the RSCCN dataset achieves the accuracy rate of 90.34 % at the 11th epoch while decreasing the epoch value to one makes the accuracy rate drop to 74%. On the other extreme, setting an increased value of batch size to 200 decreases the accuracy rate at the 11th epoch is 86.5%, and 63% when using one epoch only. On the other hand, selecting the kernel size is loosely related to data set. From a practical point of view, the filter size 20 produces 70.4286%. The last performed image size experiment shows a dependency in the accuracy improvement. However, an expensive performance gain had been noticed. The represented conclusion opens the opportunities toward a better classification performance in various applications such as planetary remote sensing.Keywords: CNNs, hyperparamters, remote sensing, land cover, land use
Procedia PDF Downloads 168113 Effect of Laser Ablation OTR Films and High Concentration Carbon Dioxide for Maintaining the Freshness of Strawberry ‘Maehyang’ for Export in Modified Atmosphere Condition
Authors: Hyuk Sung Yoon, In-Lee Choi, Min Jae Jeong, Jun Pill Baek, Ho-Min Kang
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This study was conducted to improve storability by using suitable laser ablation oxygen transmission rate (OTR) films and effectiveness of high carbon dioxide at strawberry 'Maehyang' for export. Strawberries were grown by hydroponic system in Gyeongsangnam-do province. These strawberries were packed by different laser ablation OTR films (Daeryung Co., Ltd.) such as 1,300 cc, 20,000 cc, 40,000 cc, 80,000 cc, and 100,000 cc•m-2•day•atm. And CO2 injection (30%) treatment was used 20,000 cc•m-2•day•atm OTR film and perforated film was as a control. Temperature conditions were applied simulated shipping and distribution conditions from Korea to Singapore, there were stored at 3 ℃ (13 days), 10 ℃ (an hour), and 8 ℃ (7 days) for 20 days. Fresh weight loss rate was under 1% as maximum permissible weight loss in treated OTR films except perforated film as a control during storage. Carbon dioxide concentration within a package for the storage period showed a lower value than the maximum CO2 concentration tolerated range (15 %) in treated OTR films and even the concentration of high OTR film treatment; from 20,000cc to 100,000cc were less than 3%. 1,300 cc had a suitable carbon dioxide range as over 5 % under 15 % at 5 days after storage until finished experiments and CO2 injection treatment was quickly drop the 15 % at storage after 1 day, but it kept around 15 % during storage. Oxygen concentration was maintained between 10 to 15 % in 1,300 cc and CO2 injection treatments, but other treatments were kept in 19 to 21 %. Ethylene concentration was showed very higher concentration at the CO2 injection treatment than OTR treatments. In the OTR treatments, 1,300 cc showed the highest concentration in ethylene and 20,000 cc film had lowest. Firmness was maintained highest in 1,300cc, but there was not shown any significant differences among other OTR treatments. Visual quality had shown the best result in 20,000 cc that showed marketable quality until 20 days after storage. 20,000 cc and perforated film had better than other treatments in off-odor and the 1,300 cc and CO2 injection treatments have occurred strong off-odor even after 10 minutes. As a result of the difference between Hunter ‘L’ and ‘a’ values of chroma meter, the 1,300cc and CO2 injection treatments were delayed color developments and other treatments did not shown any significant differences. The results indicate that effectiveness for maintaining the freshness was best achieved at 20,000 cc•m-2•day•atm. Although 1,300 cc and CO2 injection treatments were in appropriate MA condition, it showed darkening of strawberry calyx and excessive reduction of coloring due to high carbon dioxide concentration during storage. While 1,300cc and CO2 injection treatments were considered as appropriate treatments for exports to Singapore, but the result was shown different. These results are based on cultivar characteristics of strawberry 'Maehyang'.Keywords: carbon dioxide, firmness, shelf-life, visual quality
Procedia PDF Downloads 399112 Progressive Damage Analysis of Mechanically Connected Composites
Authors: Şeyma Saliha Fidan, Ozgur Serin, Ata Mugan
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While performing verification analyses under static and dynamic loads that composite structures used in aviation are exposed to, it is necessary to obtain the bearing strength limit value for mechanically connected composite structures. For this purpose, various tests are carried out in accordance with aviation standards. There are many companies in the world that perform these tests in accordance with aviation standards, but the test costs are very high. In addition, due to the necessity of producing coupons, the high cost of coupon materials, and the long test times, it is necessary to simulate these tests on the computer. For this purpose, various test coupons were produced by using reinforcement and alignment angles of the composite radomes, which were integrated into the aircraft. Glass fiber reinforced and Quartz prepreg is used in the production of the coupons. The simulations of the tests performed according to the American Society for Testing and Materials (ASTM) D5961 Procedure C standard were performed on the computer. The analysis model was created in three dimensions for the purpose of modeling the bolt-hole contact surface realistically and obtaining the exact bearing strength value. The finite element model was carried out with the Analysis System (ANSYS). Since a physical break cannot be made in the analysis studies carried out in the virtual environment, a hypothetical break is realized by reducing the material properties. The material properties reduction coefficient was determined as 10%, which is stated to give the most realistic approach in the literature. There are various theories in this method, which is called progressive failure analysis. Because the hashin theory does not match our experimental results, the puck progressive damage method was used in all coupon analyses. When the experimental and numerical results are compared, the initial damage and the resulting force drop points, the maximum damage load values , and the bearing strength value are very close. Furthermore, low error rates and similar damage patterns were obtained in both test and simulation models. In addition, the effects of various parameters such as pre-stress, use of bushing, the ratio of the distance between the bolt hole center and the plate edge to the hole diameter (E/D), the ratio of plate width to hole diameter (W/D), hot-wet environment conditions were investigated on the bearing strength of the composite structure.Keywords: puck, finite element, bolted joint, composite
Procedia PDF Downloads 102111 Structural and Binding Studies of Peptidyl-tRNA Hydrolase from Pseudomonas aeruginosa Provide a Platform for the Structure Based Inhibitor Design against Peptidyl-tRNA Hydrolase
Authors: Sujata Sharma, Avinash Singh, Lovely Gautam, Pradeep Sharma, Mau Sinha, Asha Bhushan, Punit Kaur, Tej P. Singh
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Peptidyl-tRNA hydrolase (Pth) Pth is an essential bacterial enzyme that catalyzes the release of free tRNA and peptide moeities from peptidyl tRNAs during stalling of protein synthesis. In order to design inhibitors of Pth from Pseudomonas aeruginosa (PaPth), we have determined the structures of PaPth in its native state and in the bound states with two compounds, amino acylate-tRNA analogue (AAtA) and 5-azacytidine (AZAC). The peptidyl-tRNA hydrolase gene from Pseudomonas aeruginosa was amplified by Phusion High-Fidelity DNA Polymerase using forward and reverse primers, respectively. The E. coliBL21 (λDE3) strain was used for expression of the recombinant peptidyl-tRNA hydrolase from Pseudomonas aeruginosa. The protein was purified using a Ni-NTA superflow column. The crystallization experiments were carried out using hanging drop vapour diffusion method. The crystals diffracted to 1.50 Å resolution. The data were processed using HKL-2000. The polypeptide chain of PaPth consists of 194 amino acid residues from Met1 to Ala194. The centrally located β-structure is surrounded by α-helices from all sides except the side that has entrance to the substrate binding site. The structures of the complexes of PaPth with AAtA and AZAC showed the ligands bound to PaPth in the substrate binding cleft and interacted with protein atoms extensively. The residues that formed intermolecular hydrogen bonds with the atoms of AAtA included Asn12, His22, Asn70, Gly113, Asn116, Ser148, and Glu161 of the symmetry related molecule. The amino acids that were involved in hydrogen bonded interactions in case of AZAC included, His22, Gly113, Asn116, and Ser148. As indicated by fittings of two ligands and the number of interactions made by them with protein atoms, AAtA appears to be a more compatible with the structure of the substrate binding cleft. However, there is a further scope to achieve a better stacking than that of O-tyrosyl moiety because it is not still ideally stacked. These observations about the interactions between the protein and ligands have provided the information about the mode of binding of ligands, nature and number of interactions. This information may be useful for the design of tight inhibitors of Pth enzymes.Keywords: peptidyl tRNA hydrolase, Acinetobacter baumannii, Pth enzymes, O-tyrosyl
Procedia PDF Downloads 430110 Utilization of Bio-Glycerol to Synthesize Fuel Additive in Presence of Modified Mesoporous Heterogeneous Catalysts
Authors: Ala’a H. Al-Muhtaseb, Farrukh Jamil, Sandeep K. Saxena
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The fast growth rate of energy consumption along with world population expected to demand 50% more energy by 2030 than nowadays. At present, the energy demand is mostly provided by limited fossil fuel sources such as oil, natural gas, and coal that are resulting in dramatic increase in CO2 emissions from combustion of fossil fuels. The growth of the biodiesel industry over the last decade has resulted in a price drop because glycerol is obtained as a by-product during transesterification of vegetable oil or animal fats, which accounts for one tenth of every gallon of biodiesel produced. The production of oxygenates from glycerol gains much importance due to the excellent diesel-blending property of the oxygenates that not only improve the quality of the fuel but also increases the overall yield of the biodiesel in helping to meet the target for energy production from renewable sources for transport in the energy utilization directives. The reaction of bio-glycerol with bio-acetone was carried out in a magnetically stirred two necked round bottom flaskS. Condensation of bio-glycerol with acetone in the presence of various modified forms of beta zeolite has been done for synthesizing solketal (AB-2 modified with nitric acid, AB-3 modified with oxalic acid). Among all modified forms of beta zeolite, AB-2 showed the best performance for maximum glycerol conversion 94.26 % with 94.21 % solketal selectivity and minimum acetal formation 0.05 %. The physiochemical properties of parent beta zeolite and all its modified forms were analyzed by XRD, SEM, TEM, BET, FTIR and TPD. It has been revealed that AB-2 catalysts with high pore volume and surface area gave high glycerol conversion with maximum solketal selectivity. Despite this, the crystallinity of AB-3 was lower than AB-2 which helps to provide the shorter path length for reactants and product but due high pore volume AB-2 was preferred which gave maximum bio-glycerol conversion. Temperature does matter the glycerol conversion and selectivity of solketal, as it increases from 40 ºC to 60 ºC the conversion of glycerol rises from 80.04 % to 94.26 % and selectivity of solketal from 80.0 % to 94.21 % but further increase in temperature to 100 ºC glycerol conversion reduced to 93.06 % and solketal selectivity to 92.08 %. AB-2 was found to be highly stable as up to 4 repeated experimental runs there was less than 10% decrease in its activity. This process offers an attractive route for converting bio-glycerol, the main by-product of biodiesel to solketal with bio-acetone; a value-added green product with potential industrial applications as a valuable green fuel additive or combustion promoter for gasoline/diesel engines.Keywords: beta-zeolite, bio-glycerol, catalyst, solketal
Procedia PDF Downloads 214109 A Bottleneck-Aware Power Management Scheme in Heterogeneous Processors for Web Apps
Authors: Inyoung Park, Youngjoo Woo, Euiseong Seo
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With the advent of WebGL, Web apps are now able to provide high quality graphics by utilizing the underlying graphic processing units (GPUs). Despite that the Web apps are becoming common and popular, the current power management schemes, which were devised for the conventional native applications, are suboptimal for Web apps because of the additional layer, the Web browser, between OS and application. The Web browser running on a CPU issues GL commands, which are for rendering images to be displayed by the Web app currently running, to the GPU and the GPU processes them. The size and number of issued GL commands determine the processing load of the GPU. While the GPU is processing the GL commands, CPU simultaneously executes the other compute intensive threads. The actual user experience will be determined by either CPU processing or GPU processing depending on which of the two is the more demanded resource. For example, when the GPU work queue is saturated by the outstanding commands, lowering the performance level of the CPU does not affect the user experience because it is already deteriorated by the retarded execution of GPU commands. Consequently, it would be desirable to lower CPU or GPU performance level to save energy when the other resource is saturated and becomes a bottleneck in the execution flow. Based on this observation, we propose a power management scheme that is specialized for the Web app runtime environment. This approach incurs two technical challenges; identification of the bottleneck resource and determination of the appropriate performance level for unsaturated resource. The proposed power management scheme uses the CPU utilization level of the Window Manager to tell which one is the bottleneck if exists. The Window Manager draws the final screen using the processed results delivered from the GPU. Thus, the Window Manager is on the critical path that determines the quality of user experience and purely executed by the CPU. The proposed scheme uses the weighted average of the Window Manager utilization to prevent excessive sensitivity and fluctuation. We classified Web apps into three categories using the analysis results that measure frame-per-second (FPS) changes under diverse CPU/GPU clock combinations. The results showed that the capability of the CPU decides user experience when the Window Manager utilization is above 90% and consequently, the proposed scheme decreases the performance level of CPU by one step. On the contrary, when its utilization is less than 60%, the bottleneck usually lies in the GPU and it is desirable to decrease the performance of GPU. Even the processing unit that is not on critical path, excessive performance drop can occur and that may adversely affect the user experience. Therefore, our scheme lowers the frequency gradually, until it finds an appropriate level by periodically checking the CPU utilization. The proposed scheme reduced the energy consumption by 10.34% on average in comparison to the conventional Linux kernel, and it worsened their FPS by 1.07% only on average.Keywords: interactive applications, power management, QoS, Web apps, WebGL
Procedia PDF Downloads 192108 Evaluation of an Integrated Supersonic System for Inertial Extraction of CO₂ in Post-Combustion Streams of Fossil Fuel Operating Power Plants
Authors: Zarina Chokparova, Ighor Uzhinsky
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Carbon dioxide emissions resulting from burning of the fossil fuels on large scales, such as oil industry or power plants, leads to a plenty of severe implications including global temperature raise, air pollution and other adverse impacts on the environment. Besides some precarious and costly ways for the alleviation of CO₂ emissions detriment in industrial scales (such as liquefaction of CO₂ and its deep-water treatment, application of adsorbents and membranes, which require careful consideration of drawback effects and their mitigation), one physically and commercially available technology for its capture and disposal is supersonic system for inertial extraction of CO₂ in after-combustion streams. Due to the flue gas with a carbon dioxide concentration of 10-15 volume percent being emitted from the combustion system, the waste stream represents a rather diluted condition at low pressure. The supersonic system induces a flue gas mixture stream to expand using a converge-and-diverge operating nozzle; the flow velocity increases to the supersonic ranges resulting in rapid drop of temperature and pressure. Thus, conversion of potential energy into the kinetic power causes a desublimation of CO₂. Solidified carbon dioxide can be sent to the separate vessel for further disposal. The major advantages of the current solution are its economic efficiency, physical stability, and compactness of the system, as well as needlessness of addition any chemical media. However, there are several challenges yet to be regarded to optimize the system: the way for increasing the size of separated CO₂ particles (as they are represented on a micrometers scale of effective diameter), reduction of the concomitant gas separated together with carbon dioxide and provision of CO₂ downstream flow purity. Moreover, determination of thermodynamic conditions of the vapor-solid mixture including specification of the valid and accurate equation of state remains to be an essential goal. Due to high speeds and temperatures reached during the process, the influence of the emitted heat should be considered, and the applicable solution model for the compressible flow need to be determined. In this report, a brief overview of the current technology status will be presented and a program for further evaluation of this approach is going to be proposed.Keywords: CO₂ sequestration, converging diverging nozzle, fossil fuel power plant emissions, inertial CO₂ extraction, supersonic post-combustion carbon dioxide capture
Procedia PDF Downloads 141107 Effect on the Integrity of the DN300 Pipe and Valves in the Cooling Water System Imposed by the Pipes and Ventilation Pipes above in an Earthquake Situation
Authors: Liang Zhang, Gang Xu, Yue Wang, Chen Li, Shao Chong Zhou
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Presently, more and more nuclear power plants are facing the issue of life extension. When a nuclear power plant applies for an extension of life, its condition needs to meet the current design standards, which is not fine for all old reactors, typically for seismic design. Seismic-grade equipment in nuclear power plants are now generally placed separately from the non-seismic-grade equipment, but it was not strictly required before. Therefore, it is very important to study whether non-seismic-grade equipment will affect the seismic-grade equipment when dropped down in an earthquake situation, which is related to the safety of nuclear power plants and future life extension applications. This research was based on the cooling water system with the seismic and non-seismic grade equipment installed together, as an example to study whether the non-seismic-grade equipment such as DN50 fire pipes and ventilation pipes arranged above will damage the DN300 pipes and valves arranged below when earthquakes occur. In the study, the simulation was carried out by ANSYS / LY-DYNA, and Johnson-Cook was used as the material model and failure model. For the experiments, the relative positions of objects in the room were restored by 1: 1. In the experiment, the pipes and valves were filled with water with a pressure of 0.785 MPa. The pressure-holding performance of the pipe was used as a criterion for damage. In addition to the pressure-holding performance, the opening torque was considered as well for the valves. The research results show that when the 10-meter-long DN50 pipe was dropped from the position of 8 meters height and the 8-meter-long air pipe dropped from a position of 3.6 meters height, they do not affect the integrity of DN300 pipe below. There is no failure phenomenon in the simulation as well. After the experiment, the pressure drop in two hours for the pipe is less than 0.1%. The main body of the valve does not fail either. The opening torque change after the experiment is less than 0.5%, but the handwheel of the valve may break, which affects the opening actions. In summary, impacts of the upper pipes and ventilation pipes dropdown on the integrity of the DN300 pipes and valves below in a cooling water system of a typical second-generation nuclear power plant under an earthquake was studied. As a result, the functionality of the DN300 pipeline and the valves themselves are not significantly affected, but the handwheel of the valve or similar articles can probably be broken and need to take care.Keywords: cooling water system, earthquake, integrity, pipe and valve
Procedia PDF Downloads 112106 Children Overcome Learning Disadvantages through Mother-Tongue Based Multi-Lingual Education Programme
Authors: Binay Pattanayak
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More than 9 out of every 10 children in Jharkhand struggle to understand the texts and teachers in public schools. The medium of learning in the schools is Hindi, which is very different in structure and vocabulary than those in children’s home languages. Hence around 3 out of 10 children enrolled in early grades drop out in these schools. The state realized the cause of children’s high dropout in 2013-14 when the M-TALL, the language research shared the findings of a state-wide socio-linguistic study. The study findings suggested that there was a great need for initiating a mother-tongue based multilingual education (MTB-MLE) programme for the state in early grades starting from pre-school level. Accordingly, M-TALL in partnership with department of education designed two learning packages: Bhasha Puliya pre-school education programme for 3-6-year-old children for their school readiness with bilingual picture dictionaries in 9 tribal and regional languages. This was followed by a plan for MTB-MLE programme for early primary grades. For this textbooks in five tribal and two regional languages were developed under the guidance of the author. These books were printed and circulated in the 1000 schools of the state for each child. Teachers and community members were trained for facilitating culturally sensitive mother-tongue based learning activities in and around the schools. The mother-tongue based approach of learning has worked very effectively in enabling them to acquire the basic literacy and numeracy skills in own mother-tongues. Using this basic early grade reading skills, these children are able to learn Hindi and English systematically. Community resource groups were constituted in each school for promoting storytelling, singing, painting, dancing, acting, riddles, humor, sanitation, health, nutrition, protection, etc. and were trained. School academic calendar was designed in each school to enable the community resource persons to visit the school as per the learning plan to assist children and teacher in facilitating rich cultural activities in mother-tongue. This enables children to take part in plethora of learning activities and acquire desired knowledge, skills and interest in mother-tongues. Also in this process, it is attempted to promote 21st Century learning skills by enabling children to apply their new knowledge and skills to look at their local issues and address those in a collective manner through team work, innovations and leadership.Keywords: community resource groups, learning, MTB-MLE, multilingual, socio-linguistic survey
Procedia PDF Downloads 236105 Promoting Patients' Adherence to Home-Based Rehabilitation: A Randomised Controlled Trial of a Theory-Driven Mobile Application
Authors: Derwin K. C. Chan, Alfred S. Y. Lee
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The integrated model of self-determination theory and the theory of planned behaviour has been successfully applied to explain individuals’ adherence to health behaviours, including behavioural adherence toward rehabilitation. This study was a randomised controlled trial that examined the effectiveness of an mHealth intervention (i.e., mobile application) developed based on this integrated model in promoting treatment adherence of patients of anterior cruciate ligament rupture during their post-surgery home-based rehabilitation period. Subjects were 67 outpatients (aged between 18 and 60) who undertook anterior cruciate ligament (ACL) reconstruction surgery for less than 2 months for this study. Participants were randomly assigned either into the treatment group (who received the smartphone application; N = 32) and control group (who receive standard treatment only; N = 35), and completed psychological measures relating to the theories (e.g., motivations, social cognitive factors, and behavioural adherence) and clinical outcome measures (e.g., subjective knee function (IKDC), laxity (KT-1000), muscle strength (Biodex)) relating to ACL recovery at baseline, 2-month, and 4-month. Generalise estimating equation showed the interaction between group and time was significant on intention was only significant for intention (Wald x² = 5.23, p = .02), that of perceived behavioural control (Wald x² = 3.19, p = .07), behavioural adherence (Wald x² = 3.08, p = .08, and subjective knee evaluation (Wald x² = 2.97, p = .09) were marginally significant. Post-hoc between-subject analysis showed that control group had significant drop of perceived behavioural control (p < .01), subjective norm (p < .01) and intention (p < .01), behavioural adherence (p < .01) from baseline to 4-month, but such pattern was not observed in the treatment group. The treatment group had a significant decrease of behavioural adherence (p < .05) in the 2-month, but such a decrease was not observed in 4-month (p > .05). Although the subjective knee evaluation in both group significantly improved at 2-month and 4-month from the baseline (p < .05), and the improvements in the control group (mean improvement at 4-month = 40.18) were slightly stronger than the treatment group (mean improvement at 4-month = 34.52). In conclusion, the findings showed that the theory driven mobile application ameliorated the decline of treatment intention of home-based rehabilitation. Patients in the treatment group also reported better muscle strength than control group at 4-month follow-up. Overall, the mobile application has shown promises on tackling the problem of orthopaedics outpatients’ non-adherence to medical treatment.Keywords: self-determination theory, theory of planned behaviour, mobile health, orthopaedic patients
Procedia PDF Downloads 198104 Support Services in Open and Distance Education: An Integrated Model of Open Universities
Authors: Evrim Genc Kumtepe, Elif Toprak, Aylin Ozturk, Gamze Tuna, Hakan Kilinc, Irem Aydin Menderis
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Support services are very significant elements for all educational institutions in general; however, for distance learners, these services are more essential than traditional (face-to-face) counterparts. One of the most important reasons for this is that learners and instructors do not share the same physical environment and that distance learning settings generally require intrapersonal interactions rather than interpersonal ones. Some learners in distance learning programs feel isolated. Furthermore, some fail to feel a sense of belonging to the institution because of lack of self-management skills, lack of motivation levels, and the need of being socialized, so that they are more likely to fail or drop out of an online class. In order to overcome all these problems, support services have emerged as a critical element for an effective and sustainable distance education system. Within the context of distance education support services, it is natural to include technology-based and web-based services and also the related materials. Moreover, institutions in education sector are expected to use information and communication technologies effectively in order to be successful in educational activities and programs. In terms of the sustainability of the system, an institution should provide distance education services through ICT enabled processes to support all stakeholders in the system, particularly distance learners. In this study, it is envisaged to develop a model based on the current support services literature in the field of open and distance learning and the applications of the distance higher education institutions. Specifically, content analysis technique is used to evaluate the existing literature in the distance education support services, the information published on websites, and applications of distance higher education institutions across the world. A total of 60 institutions met the inclusion criteria which are language option (English) and availability of materials in the websites. The six field experts contributed to brainstorming process to develop and extract codes for the coding scheme. During the coding process, these preset and emergent codes are used to conduct analyses. Two coders independently reviewed and coded each assigned website to ensure that all coders are interpreting the data the same way and to establish inter-coder reliability. Once each web page is included in descriptive and relational analysis, a model of support services is developed by examining the generated codes and themes. It is believed that such a model would serve as a quality guide for future institutions, as well as the current ones.Keywords: support services, open education, distance learning, support model
Procedia PDF Downloads 197103 The Influence of Hydrolyzed Cartilage Collagen on General Mobility and Wellbeing of an Active Population
Authors: Sara De Pelsmaeker, Catarina Ferreira da Silva, Janne Prawit
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Recent studies show that enzymatically hydrolysed collagen is absorbed and distributed to joint tissues, where it has analgesic and active anti-inflammatory properties. Reviews of the associated relevant literature also support this theory. However, these studies are all using hydrolyzed collagen from animal hide or skin. This study looks into the effect of daily supplementation of hydrolyzed cartilage collagen (HCC), which has a different composition. A consumer study was set up using a double-blind placebo-controlled design with a control group using twice a day 0.5gr of maltodextrin and an experimental group using twice 0.5g of HCC, over a trial period of 12 weeks. A follow-up phase of 4 weeks without supplementation was taken into the experiment to investigate the ‘wash-out’ phase. As this consumer study was conducted during the lockdown periods, a specific app was designed to follow up with the participants. The app had the advantage that in this way, the motivation of the participants was enhanced and the drop-out range of participants was lower than normally seen in consumer studies. Participants were recruited via various sports and health clubs across the UK as we targeted a general population of people that considered themselves in good health. Exclusion criteria were ‘not experiencing any medical conditions’ and ‘not taking any prescribed medication’. A minimum requirement was that they regularly engaged in some level of physical activity. The participants had to log the type of activity that they conducted and the duration of the activity. Weekly, participants were providing feedback on their joint health and subjective pain using the validated pain measuring instrument Visual Analogue Scale (VAS). The weekly repoAbstract Public Health and Wellbeing Conferencerting section in the app was designed with simplicity and based on the accuracy demonstrated in previous similar studies to track subjective pain measures of participants. At the beginning of the trial, each participant indicated their baseline on joint pain. The results of this consumer study indicated that HCC significantly improved joint health and subjective pain scores compared to the placebo group. No significant differences were found between different demographic groups (age or gender). The level of activity, going from high intensive training to regular walking, did not significantly influence the effect of the HCC. The results of the wash-out phase indicated that when the participants stopped the HCC supplementation, their subjective pain scores increased again to the baseline. In conclusion, the results gave a positive indication that the daily supplementation of HCC can contribute to the overall mobility and wellbeing of a general active populationKeywords: VAS-score, food supplement, mobility, joint health
Procedia PDF Downloads 162102 Prevalence of Emotional Problems among Adolescent Students of Corporation Schools in Chennai
Authors: Vithya Veeramani, Karunanidhi Subbaiah
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Emotional problems were found to be the predominant cause of suicide and second leading cause of death among adolescents in India. Emotional problems seem to be the underlying cause for various other severe psycho-social problems experienced in adolescence and also in later years of life. The Corporation schools in Chennai city are named as Chennai High School or Chennai Higher Secondary School run by the Corporation of Chennai. These schools fulfill the educational needs of students who hail from lower socio-economic status living in slums of the Chennai city. Adolescent students of Chennai schools tend to lack basic needs like food, clothes, shelter, etc. Some of the other significant problems faced by them are broken family, lack of parental support, frequent quarrel between parents, alcoholic parents, drug abuse and substance abuse among parents and neighbors, extended family, illiterate parents, deprivation of love and care, and lack of sense of belongingness. This prevailing condition may affect them emotionally and could lead to maladaptive behaviour, aggressiveness, poor interpersonal relationship with others, school refusal behaviour, school drop-out, suicide, etc. Therefore, it is very important to investigate the emotional problems faced by the adolescent students studying in Chennai schools, Chennai. A cross-sectional survey design was used to find the prevalence of emotional problems among adolescent students. Cluster sampling technique was used to select the schools for the present study considering the school as a cluster. In total, there are 15 zones, under the control of Chennai Corporation, of which only 7 zones have Corporation Schools in Chennai city, comprising of 32 Chennai Higher Secondary Schools and 38 Chennai High Schools. Out of these 70 schools, 29 schools comprising of 17 high schools and 12 higher secondary schools were selected randomly using lottery method. A sample of 2594 adolescent students from 9th standard and 11th standard was chosen for the study. Percentage analysis was done to find out the prevalence rate of emotional problems among adolescents students studying in Chennai Schools. Results of the study revealed that, out of 2594 students surveyed, 21.04% adolescent students were found to have academic problems (n = 546), 15.99% adolescent students had social problems (n = 415), behaviour problems was found to be prevalent among 12.87% adolescent students (n = 334), depression was prevalent among 15.88% adolescent students (n = 412) and anxiety was prevalent among 14.42% adolescent students (n = 374). Prevalence of emotional problems among male and female revealed that academic problems were more prevalent compared to other problems. Behaviour problems were least prevalent among boys and anxiety was least prevalent among girls than other problems. The overall prevalence rate of emotional problems was found to be on an increasing trend among adolescent students of low socio-economic status in Chennai city. The findings indicated the need for intervention to prevent and rehabilitate these adolescent students.Keywords: adolescents, corporation schools, emotional problems, prevalence
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