Search results for: current mode control
13426 A Low-Cost Memristor Based on Hybrid Structures of Metal-Oxide Quantum Dots and Thin Films
Authors: Amir Shariffar, Haider Salman, Tanveer Siddique, Omar Manasreh
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According to the recent studies on metal-oxide memristors, researchers tend to improve the stability, endurance, and uniformity of resistive switching (RS) behavior in memristors. Specifically, the main challenge is to prevent abrupt ruptures in the memristor’s filament during the RS process. To address this problem, we are proposing a low-cost hybrid structure of metal oxide quantum dots (QDs) and thin films to control the formation of filaments in memristors. We aim to use metal oxide quantum dots because of their unique electronic properties and quantum confinement, which may improve the resistive switching behavior. QDs have discrete energy spectra due to electron confinement in three-dimensional space. Because of Coulomb repulsion between electrons, only a few free electrons are contained in a quantum dot. This fact might guide the growth direction for the conducting filaments in the metal oxide memristor. As a result, it is expected that QDs can improve the endurance and uniformity of RS behavior in memristors. Moreover, we use a hybrid structure of intrinsic n-type quantum dots and p-type thin films to introduce a potential barrier at the junction that can smooth the transition between high and low resistance states. A bottom-up approach is used for fabricating the proposed memristor using different types of metal-oxide QDs and thin films. We synthesize QDs including, zinc oxide, molybdenum trioxide, and nickel oxide combined with spin-coated thin films of titanium dioxide, copper oxide, and hafnium dioxide. We employ fluorine-doped tin oxide (FTO) coated glass as the substrate for deposition and bottom electrode. Then, the active layer composed of one type of quantum dots, and the opposite type of thin films is spin-coated onto the FTO. Lastly, circular gold electrodes are deposited with a shadow mask by using electron-beam (e-beam) evaporation at room temperature. The fabricated devices are characterized using a probe station with a semiconductor parameter analyzer. The current-voltage (I-V) characterization is analyzed for each device to determine the conduction mechanism. We evaluate the memristor’s performance in terms of stability, endurance, and retention time to identify the optimal memristive structure. Finally, we assess the proposed hypothesis before we proceed to the optimization process for fabricating the memristor.Keywords: memristor, quantum dot, resistive switching, thin film
Procedia PDF Downloads 12213425 Dimethyl fumarate Alleviates Valproic Acid-Induced Autism in Wistar Rats via Activating NRF-2 and Inhibiting NF-κB Pathways
Authors: Sandy Elsayed, Aya Mohamed, Noha Nassar
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Introduction: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social deficits and repetitive behavior. Multiple studies suggest that oxidative stress and neuroinflammation are key factors in the etiology of ASD and often associated with worsening of ASD-related behaviors. Nuclear factor erythroid 2-related factor 2 (NRF-2) is a transcription factor that promotes expression of antioxidant response element genes in oxidative stress. In ASD subjects, decreased expression of NRF-2 in frontal cortex shifted the redox homeostasis towards oxidative stress, and resulted in inflammation evidenced by elevation of nuclear factor kappa B (NF-κB) transcriptional activity. Dimethyl fumarate (DMF) is a NRF-2 activator that is used in the treatment of psoriasis and multiple sclerosis. It participates in the transcriptional control of inflammatory factors via inhibition of NF-κB and its downstream targets. This study aimed to investigate the role of DMF in alleviating the cognitive impairments and behavior deficits associated with ASD through mitigation of oxidative stress and inflammation in prenatal valproic acid (VPA) rat model of autism. Methods: Pregnant female Wistar rats received a single intraperitoneal injection of VPA (600 mg/kg) to induce autistic-like-behavioral and neurobiological alterations in their offspring. Chronic oral gavage of DMF (150mg/kg/day) started from postnatal day (PND) 24 till PND62 (39 days). Prenatal VPA exposure elicited autistic behaviors including decreased social interaction and stereotyped behavior. Social interaction was evaluated using three-chamber sociability test and calculation of sociability index (SI), while stereotyped repetitive behavior and anxiety associated with ASD were assessed using marble burying test (MBT). Biochemical analyses were done on prefrontal cortex homogenates including NRF-2, and NF-κB expression. Moreover, inducible nitric oxide synthase (iNOS) gene expression and tumor necrosis factor (TNF-) protein expression were evaluated as markers of inflammation. Results: Prenatal VPA elicited decreased social interaction shown by decreased SI compared to control group (p < 0.001) and DMF enhanced SI (p < 0.05). In MBT, prenatal injection of VPA manifested stereotyped behavior and enhanced number of buried marbles compared to control (p < 0.05) and DMF reduced the anxiety-related behavior in rats exhibiting ASD-like behaviors (p < 0.05). In prefrontal cortex, NRF-2 expression was downregulated in prenatal VPA model (p < 0.0001) and DMF reversed this effect (p < 0.0001). The inflammatory transcription factor NF-κB was elevated in prenatal VPA model (p < 0.0001) and reduced (p < 0.0001) upon NRF-2 activation by DMF. Prenatal VPA expressed higher levels of proinflammatory cytokine TNF- compared to control group (p < 0.0001) and DMF reduced it (p < 0.0001). Finally, the gene expression of iNOS was downregulated upon NRF-2 activation by DMF (p < 0.01). Conclusion: This study proposes that DMF is a potential agent that can be used to ameliorate autistic-like-changes through NRF-2 activation along with NF-κB downregulation and therefore, it is a promising novel therapy for ASD.Keywords: autism spectrum disorders, dimethyl fumarate, neuroinflammation, NRF-2
Procedia PDF Downloads 4113424 The Effect of a 12 Week Rhythmic Movement Intervention on Selected Biomotor Abilities on Academy Rugby Players
Authors: Jocelyn Solomons, Kraak
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Rhythmic movement, also referred to as “dance”, involves the execution of different motor skills as well as the integration and sequencing of actions between limbs, timing and spatial precision. The aim of this study was therefore to investigate and compare the effect of a 16-week rhythmic movement intervention on flexibility, dynamic balance, agility, power and local muscular endurance of academy rugby players in the Western Cape, according to positional groups. Players (N ¼ 54) (age 18.66 0.81 years; height 1.76 0.69 cm; weight 76.77 10.69 kg), were randomly divided into a treatment-control [TCA] (n ¼ 28) and a control-treatment [CTB] (n ¼ 26) group. In this crossover experimental design, the interaction effect of the treatment order and the treatment time between the TCA and CTB group, was determined. Results indicated a statistically significant improvement (p < 0.05) in agility2 (p ¼ 0.06), power2 (p ¼ 0.05), local muscular endurance1 (p ¼ 0.01) & 3 (p ¼ 0.01) and dynamic balance (p < 0.01). Likewise, forwards and backs also showed statistically significant improvements (p < 0.05) per positional groups. Therefore, a rhythmic movement intervention has the potential to improve rugby-specific bio-motor skills and furthermore, improve positional specific skills should it be designed with positional groups in mind. Future studies should investigate, not only the effect of rhythmic movement on improving specific rugby bio-motor skills, but the potential of its application as an alternative training method during off- season (or detraining phases) or as a recovery method.Keywords: agility, dance, dynamic balance, flexibility, local muscular endurance, power, training
Procedia PDF Downloads 6213423 Exploring the Impact of Cultural Values on the Performance of Women Bureaucrats in Pakistan
Authors: Fariya Tahreen
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Women are an important part of the society comprising more than 50% population of the world. Participation of women in public services is increasing in the present era while cultural values embedded with gender differences still influencing the performance of working women. Many researches have been carried out on cultural impact on working women like managers, doctors, and lawyers and other public servants. But very rare efforts were made to study the impact of cultural values on the performance of women bureaucrats. The present study aimed to find out the relationship of cultural values (i.e., collective identity, gender segregation, and gender asymmetrical relations) with the performance of women bureaucrats. Sample of the present study comprised of 130 women bureaucrats from the Office Management Group, Inland Revenue, District Management Group, and Pakistan Police Services which is selected by convenient sampling technique. The locale of the study was Islamabad, Rawalpindi and Lahore city. The current research study was conducted by using a quantitative approach in research method and data were collected through survey method. The measures used in the study included: personal information, three main cultural values, and performance of women bureaucrats. Uni-variate and bi-variate analyses were implied by using correlation and multiple linear regression test. The current study shows a negative significant relationship between cultural values and performance of women bureaucrats (R²= 0.790, p-value 0.000). It shows that cultural values (collective identity, gender segregation and gender asymmetrical relations) significantly influence the performance of women bureaucrats. Due to the influence and pressure of these cultural values, women bureaucrats give less time to the office and avail more leaves. They also avoid contacting with male colleagues, public dealings, field visits and playing leadership role. Further, they attend fewer meetings of policy formulation due to given less importance for it. In a nutshell, the study concluded that cultural values significantly influence the performance of women bureaucrats in Pakistan.Keywords: cultural values, performance, Pakistan, women bureaucrats
Procedia PDF Downloads 12513422 Analysis of the Homogeneous Turbulence Structure in Uniformly Sheared Bubbly Flow Using First and Second Order Turbulence Closures
Authors: Hela Ayeb Mrabtini, Ghazi Bellakhal, Jamel Chahed
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The presence of the dispersed phase in gas-liquid bubbly flow considerably alters the liquid turbulence. The bubbles induce turbulent fluctuations that enhance the global liquid turbulence level and alter the mechanisms of turbulence. RANS modeling of uniformly sheared flows on an isolated sphere centered in a control volume is performed using first and second order turbulence closures. The sphere is placed in the production-dissipation equilibrium zone where the liquid velocity is set equal to the relative velocity of the bubbles. The void fraction is determined by the ratio between the sphere volume and the control volume. The analysis of the turbulence statistics on the control volume provides numerical results that are interpreted with regard to the effect of the bubbles wakes on the turbulence structure in uniformly sheared bubbly flow. We assumed for this purpose that at low void fraction where there is no hydrodynamic interaction between the bubbles, the single-phase flow simulation on an isolated sphere is representative on statistical average of a sphere network. The numerical simulations were firstly validated against the experimental data of bubbly homogeneous turbulence with constant shear and then extended to produce numerical results for a wide range of shear rates from 0 to 10 s^-1. These results are compared with our turbulence closure proposed for gas-liquid bubbly flows. In this closure, the turbulent stress tensor in the liquid is split into a turbulent dissipative part produced by the gradient of the mean velocity which also contains the turbulence generated in the bubble wakes and a pseudo-turbulent non-dissipative part induced by the bubbles displacements. Each part is determined by a specific transport equation. The simulations of uniformly sheared flows on an isolated sphere reproduce the mechanisms related to the turbulent part, and the numerical results are in perfect accordance with the modeling of the transport equation of the turbulent part. The reduction of second order turbulence closure provides a description of the modification of turbulence structure by the bubbles presence using a dimensionless number expressed in terms of two-time scales characterizing the turbulence induced by the shear and that induced by bubbles displacements. The numerical simulations carried out in the framework of a comprehensive analysis reproduce particularly the attenuation of the turbulent friction showed in the experimental results of bubbly homogeneous turbulence subjected to a constant shear.Keywords: gas-liquid bubbly flows, homogeneous turbulence, turbulence closure, uniform shear
Procedia PDF Downloads 46013421 Fires in Historic Buildings: Assessment of Evacuation of People by Computational Simulation
Authors: Ivana R. Moser, Joao C. Souza
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Building fires are random phenomena that can be extremely violent, and safe evacuation of people is the most guaranteed tactic in saving lives. The correct evacuation of buildings, and other spaces occupied by people, means leaving the place in a short time and by the appropriate way. It depends on the perception of spaces by the individual, the architectural layout and the presence of appropriate routing systems. As historical buildings were constructed in other times, when, as in general, the current security requirements were not available yet, it is necessary to adapt these spaces to make them safe. Computer models of evacuation simulation are widely used tools for assessing the safety of people in a building or agglomeration sites and these are associated with the analysis of human behaviour, makes the results of emergency evacuation more correct and conclusive. The objective of this research is the performance evaluation of historical interest buildings, regarding the safe evacuation of people, through computer simulation, using PTV Viswalk software. The buildings objects of study are the Colégio Catarinense, centennial building, located in the city of Florianópolis, Santa Catarina / Brazil. The software used uses the variables of human behaviour, such as: avoid collision with other pedestrians and avoid obstacles. Scenarios were run on the three-dimensional models and the contribution to safety in risk situations was verified as an alternative measure, especially in the impossibility of applying those measures foreseen by the current fire safety codes in Brazil. The simulations verified the evacuation time in situations of normality and emergency situations, as well as indicate the bottlenecks and critical points of the studied buildings, to seek solutions to prevent and correct these undesirable events. It is understood that adopting an advanced computational performance-based approach promotes greater knowledge of the building and how people behave in these specific environments, in emergency situations.Keywords: computer simulation, escape routes, fire safety, historic buildings, human behavior
Procedia PDF Downloads 18713420 The Influence of Different Green Roof Vegetation on Indoor Temperature in Semi-Arid Climate Cyprus
Authors: Sinem Yıldırım, Çimen Özburak, Özge Özden
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Cities are facing a growing environmental issue as a result of the combined effect of urbanization and climate change. Climate change is the most conspicuousimpact on environmental issues. Nowadays, energy conservation is a very important subject for planners. It is known that green roofs can provide environmental benefits, which include building insulation and mitigating urban heat island effect within the cities. Some of the studies shown that green roofs regulate roof temperature and they have an effect on indoor temperatures of buildings. This research looks at the experimental investigation of different type green roof vegetation with control of no vegetation and their effect on indoor temperatures. The research has been carried out at Near East University Campus with the duration of four months in Nicosia, Cyprus. The experiment was consisting of four green roof types; three of them covered with vegetation, and one of them was not vegetated for control of the experiment. Each hut had 2.7 m2 roof areas, and the soil depth was 8 cm. Mediterranean climate drought resistant ground covers and shrubs were planted on the roof of the three huts. Three different vegetation type was used: 1-Low growing ground cover succulents 2-Mixture of low growing succulents and low shrubs 3-Mixture of low growing succulents, low shrubs, and high growing foliage plantsElitech RC-5 temperature data loggers were used in order to measure indoor temperatures of the huts. Research results were shown that the hut with a highly vegetated roof had the lowest temperatures during hot summer period in Cyprus.Keywords: green roofs, indoor temperature, vegetation, mediterranean, cyprus
Procedia PDF Downloads 20713419 Effects of Alpha Lipoic Acid on Limb Lengths in Neonatal Rats Exposed to Maternal Tobacco Smoke
Authors: Ramazan F. Akkoc, Elif Erdem, Nalan Kaya, Gonca Ozan, D. Özlem Dabak, Enver Ozan
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Maternal tobacco smoke exposure is known to cause growth retardation in the neonatal skeletal system. Alpha lipoic acid, a natural antioxidant found in some foods, limits the activities of osteoclasts and supports the osteoblast's bone formation mechanism. In this study, it was aimed to investigate the effects of alpha lipoic acid (ALA) on the height, long bones and tail lengths of pups exposed to maternal tobacco smoke. The rats were divided into four groups: 1) control group, 2) tobacco smoke group, 3) tobacco smoke + ALA group, and 4) ALA group. Rats in the group 2 (tobacco smoke), group 3 (tobacco smoke + ALA) were exposed to tobacco smoke twice a day for one hour starting from eight weeks before mating and during pregnancy. In addition to tobacco smoke, 20 mg/kg of alpha lipoic acid was administered via oral gavage to the rats in the group 3 (tobacco smoke + ALA). Only alpha lipoic acid was administered to the rats in the group 4. On day 21 postpartum, the height and tail lengths of the pups in all groups were measured, and the length of the extremity long bones was measured after decapitation. All morphometric measurements performed in group 2 (tobacco smoke) showed a significant decrease compared to group 1 (control), while all measurements in group 3 (tobacco smoke + ALA) showed a significant increase compared to group 2 (tobacco smoke). It has been shown that ALA has a protective effect against the regression of height, long bones and tail lengths of pups exposed to maternal tobacco smoke.Keywords: alpha lipoic acid, bone, morphometry, rat, tobacco smoke
Procedia PDF Downloads 36613418 Women’s Financial Literacy and Family Financial Fragility
Authors: Pepur Sandra, Bulog Ivana, Rimac Smiljanić Ana
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During the COVID-19 pandemic, stress and family financial fragility arose worldwide. Economic and health uncertainty created new pressure on the everyday life of families. The work from home, homeschooling, and care of other family members caused an increase in unpaid work and generated a new division of intrahousehold. As many times before, women have taken the higher burden. This paper analyzes family stress and finance during the COVID-19 pandemic. We propose that women's inclusion in paid and unpaid work and their financial literacy influence family finances. We build up our assumptions according to the two theories that explain intrahousehold family decision-making: traditional and barging models. The traditional model assumes that partners specialize in their roles in line with time availability. Consequently, partners less engaged in payable working activities will spend more time on domestic activities and vice versa. According to the bargaining model, each individual has their preferences, and the one with more household bargaining power, e.g., higher income, higher level of education, better employment, or higher financial knowledge, is likely to make family decisions and avoid unpaid work. Our results are based on an anonymous and voluntary survey of 869 valid responses from women older than 18 conducted in Croatia at the beginning of 2021. We found that families who experienced delays in settling current obligations before the pandemic were in a worse financial situation during the pandemic. However, all families reported problems settling current obligations during pandemic times regardless of their financial condition before the crisis. Women from families with financial issues reported higher levels of family and personal stress during the pandemic. Furthermore, we provide evidence that more women's unpaid work negatively affects the family's financial fragility during the pandemic. In addition, in families where women have better financial literacy and are more financially independent, families cope better with finance before and during pandemics.Keywords: family financial fragility, stress, unpaid work, women's financial literacy
Procedia PDF Downloads 7713417 Quorum-Sensing Driven Inhibitors for Mitigating Microbial Influenced Corrosion
Authors: Asma Lamin, Anna H. Kaksonen, Ivan Cole, Paul White, Xiao-Bo Chen
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Microbiologically influenced corrosion (MIC) is a process in which microorganisms initiate, facilitate, or accelerate the electrochemical corrosion reactions of metallic components. Several reports documented that MIC accounts for about 20 to 40 % of the total cost of corrosion. Biofilm formation due to the presence of microorganisms on the surface of metal components is known to play a vital role in MIC, which can lead to severe consequences in various environmental and industrial settings. Quorum sensing (QS) system plays a major role in regulating biofilm formation and control the expression of some microbial enzymes. QS is a communication mechanism between microorganisms that involves the regulation of gene expression as a response to the microbial cell density within an environment. This process is employed by both Gram-positive and Gram-negative bacteria to regulate different physiological functions. QS involves production, detection, and responses to signalling chemicals, known as auto-inducers. QS controls specific processes important for the microbial community, such as biofilm formation, virulence factor expression, production of secondary metabolites and stress adaptation mechanisms. The use of QS inhibitors (QSIs) has been proposed as a possible solution to biofilm related challenges in many different applications. Although QSIs have demonstrated some strength in tackling biofouling, QSI-based strategies to control microbially influenced corrosion have not been thoroughly investigated. As such, our research aims to target the QS mechanisms as a strategy for mitigating MIC on metal surfaces in engineered systems.Keywords: quorum sensing, quorum quenching, biofilm, biocorrosion
Procedia PDF Downloads 9013416 Hemoglobin Levels at a Standalone Dialysis Unit
Authors: Babu Shersad, Partha Banerjee
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Reduction in haemoglobin levels has been implicated to be a cause for reduced exercise tolerance and cardiovascular complications of chronic renal diseases. Trends of hemoglobin levels in patients on haemodialysis could be an indicator of efficacy of hemodialysis and an indicator of quality of life in haemodialysis patients. In the UAE, the rate of growth (of patients on dialysis) is 10 to 15 per cent per year. The primary mode of haemodialysis in the region is based on in-patient hospital-based hemodialysis units. The increase in risk of cardiovascular and cerebrovascular morbidity as well as mortality in pre-dialysis Chronic Renal Disease has been reported. However, data on the health burden on haemodialysis in standalone dialysis facilities is very scarce. This is mainly due to the paucity of ambulatory centres for haemodialysis in the region. AMSA is the first center to offer standalone dialysis in the UAE and a study over a one year period was performed. Patient data was analyzed using a questionnaire for 45 patients with an average of 2.5 dialysis sessions per week. All patients were on chronic haemodialysis as outpatients. The trends of haemoglobin levels as an independent variable were evaluated. These trends were interpreted in comparison with other parameters of renal function (creatinine, uric acid, blood pressure and ferritin). Trends indicate an increase in hemoglobin levels with increased supplementation of iron and erythropoietin over time. The adequacy of hemodialysis shows improvement concomitantly. This, in turn, correlates with better patient outcomes and has a direct impact on morbidity and mortality. This study is a pilot study and further studies are indicated so that objective parameters can be studied and validated for hemodialysis in the region.Keywords: haemodialysis, haemoglobin in haemodialysis, haemodialysis parameters, erythropoietic agents in haemodialysis
Procedia PDF Downloads 28813415 Effect of Online Mindfulness Training to Tertiary Students’ Mental Health: An Experimental Research
Authors: Abigaile Rose Mary R. Capay, Janne Ly Castillon-Gilpo, Sheila A. Javier
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The transition to online learning has been a challenging feat on the mental health of tertiary students. This study investigated whether learning mindfulness strategies online would help in improving students’ imagination, conscientiousness, extraversion, agreeableness and emotional stability, as measured by the International Personality Item Pool (IPIP) Big Five Factor Markers, as well as their dispositional mindfulness as measured by the Mindfulness Attention Awareness Scale (MAAS). Fifty-two college students participated in the experiment. The 23 participants assigned to the treatment condition received 6-weekly experiential sessions of online mindfulness training and were advised to follow a daily mindfulness practice, while the 29 participants from the control group only received a 1-hour lecture. Scores were collected at pretest and posttest. Findings show that there was a significant difference in the pretest and posttest scores of students assigned in the treatment group, likewise medium effect sizes in the variables: dispositional mindfulness (t (22) = 2.64, p = 0.015, d = .550), extraversion (t (22) = 2.76, p = 0.011, d = 0.575), emotional stability (t (22) = 2.99, p = 0.007, d = .624), conscientiousness (t (22) = 2.74, p = 0.012, d = .572) and imagination (t (22) = 4.08, p < .001), but not for agreeableness (t (22) = 2.01, p = 0.057, d = .419). No significant differences were observed on the scores of the control group. Educational institutions are recommended to consider teaching basic mindfulness strategies to tertiary students, as a valuable resource in improving their mental health as they navigate through adjustments in online learning.Keywords: mindfulness, school-based interventions, MAAS, IPIP Big Five Markers, experiment
Procedia PDF Downloads 5813414 Quantum Engine Proposal using Two-level Atom Like Manipulation and Relativistic Motoring Control
Authors: Montree Bunruangses, Sonath Bhattacharyya, Somchat Sonasang, Preecha Yupapin
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A two-level system is manipulated by a microstrip add-drop circuit configured as an atom like system for wave-particle behavior investigation when its traveling speed along the circuit perimeter is the speed of light. The entangled pair formed by the upper and lower sideband peaks is bound by the angular displacement, which is given by 0≤θ≤π/2. The control signals associated with 3-peak signal frequencies are applied by the external inputs via the microstrip add-drop multiplexer ports, where they are time functions without the space term involved. When a system satisfies the speed of light conditions, the mass term has been changed to energy based on the relativistic limit described by the Lorentz factor and Einstein equation. The different applied frequencies can be utilized to form the 3-phase torques that can be applied for quantum engines. The experiment will use the two-level system circuit and be conducted in the laboratory. The 3-phase torques will be recorded and investigated for quantum engine driving purpose. The obtained results will be compared to the simulation. The optimum amplification of torque can be obtained by the resonant successive filtering operation. Torque will be vanished when the system is balanced at the stopped position, where |Time|=0, which is required to be a system stability condition. It will be discussed for future applications. A larger device may be tested in the future for realistic use. A synchronous and asynchronous driven motor is also discussed for the warp drive use.Keywords: quantum engine, relativistic motor, 3-phase torque, atomic engine
Procedia PDF Downloads 6313413 Effect of Papaverine on Neurospheres
Authors: Noura Shehab-Eldeen, Mohamed Elsherbeeny, Hossam Elmetwally, Mohamed Salama, Ahmed Lotfy, Mohamed Elgamal, Hussein Sheashaa, Mohamed Sobh
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Mitochondrial toxins including papaverine may be implicated in the etiology and pathogenesis of Parkinson's disease. The aim was to detect the effect of papaverine on the proliferation and viability of neural stem cells. Rat neural progenitor cells were isolated from embryos (E14) brains. The dispersed tissues were allowed to settle, then, The supernatant was centrifuged at 1,000 g for 5 min. The pellet was placed in Hank’s solution cultured as free-floating neurospheres Dulbecco’s modified Eagle medium (DMEM) and Hams F12 (3:1) supplemented with B27 (Invitrogen GmBH, Karlsruhe, Germany), 20 ng/mL epidermal growth factor (EGF; Biosource, Karlsruhe, Germany), 20 ng/mL recombinant human fibroblast growth factor (rhFGF; R&D Systems, Wiesbaden-Nordenstadt, Germany), and penicillin and streptomycin (1:100; Invitrogen) at 37°C with 7.5% CO2 . Differentiation was initiated by growth factor withdrawal and plating onto a poly-d-lysine/ laminin matrix. The neurospheres were fed every 2-3 days by replacing 50% of the culture media with fresh media. The culture suspension was transferred to a dish containing 16 wells. The wells were divided as follows: 4 wells received no papaverine (control), 4 wells 1 u, 4 wells 5 u and 4 wells 10 u of papaverine solution. In the next 2 weeks, photography (0,4,5,11days) and viability test were done. The photographs were analysed. Results : papaverine didn't affect proliferation of neurospheres, while it affected viability compared to control , this was dose related. Conclusion: This indicates the harmful effect of papaverine suggesting it to be a candidate neurotoxin causing Parkinsonism.Keywords: neurospheres, neural stem cells, papaverine, Parkinsonism
Procedia PDF Downloads 66013412 Exploring the Influence of Normative, Financial and Environmental Decision Frames in Nudging 'Green' Behaviour, and Increasing Uptake of Energy-Efficient Technologies
Authors: Rebecca Hafner, Daniel Read, David Elmes
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The persuasive potential of normative and feedback (financial vs. environmental) information in ‘nudging’ people towards making environmentally sound decisions was explored in a hypothetical choice experiment. The research was specifically focused on determining how subtle variations in the decision frame could be used to increase the selection of energy efficient vs. standard technologies, using the context of home heating choice. Participants were given a choice of a standard heating system (a gas boiler) and a relatively more-energy efficient option (a heat pump). The experiment had a 2 (normative vs. no normative information) by 3 feedback type (financial, environmental, none) design. The last group constituted the control. Half of the participants were given normative information about what the majority of others in their neighbourhood had opted to do when faced with the same choice set, prior to making their decision. The other half received no such information. Varying feedback frames were incorporated by providing participants with information on either financial or environmental savings that could be achieved by choosing the heat pump. No such information was provided in the control group. A significant interaction was found between normative information and feedback frame type. Specifically, the impact of feedback frames was found to be reduced when normative information was provided; illustrating the overriding influence of normative information on option preference. Participants were significantly more likely to select the heat pump if they were vs. were not given normative information. Yet when no normative information was provided, the persuasive influence of the financial frame was increased – highlighting this as an effective means of encouraging uptake of new technologies in this instance. Conversely, the environmental frame was not found to differ significantly from the control. Marginal carryover effects were also found for stated future real-life decision-making behaviour, with participants who were versus were not given normative information being marginally more likely to state they would consider installing a heat pump when they next need to replace their heating system in real life. We conclude that normative and financial feedback framing techniques are highly effective in increasing uptake of new, energy efficient heating technologies involving significant upfront financial outlay. The implications for researchers looking to promote ‘green’ choice in the context of new technology adoption are discussed.Keywords: energy-efficient technology adoption, environmental decision making, financial vs. environmental feedback framing techniques, social norms
Procedia PDF Downloads 30813411 An Effort at Improving Reliability of Laboratory Data in Titrimetric Analysis for Zinc Sulphate Tablets Using Validated Spreadsheet Calculators
Authors: M. A. Okezue, K. L. Clase, S. R. Byrn
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The requirement for maintaining data integrity in laboratory operations is critical for regulatory compliance. Automation of procedures reduces incidence of human errors. Quality control laboratories located in low-income economies may face some barriers in attempts to automate their processes. Since data from quality control tests on pharmaceutical products are used in making regulatory decisions, it is important that laboratory reports are accurate and reliable. Zinc Sulphate (ZnSO4) tablets is used in treatment of diarrhea in pediatric population, and as an adjunct therapy for COVID-19 regimen. Unfortunately, zinc content in these formulations is determined titrimetrically; a manual analytical procedure. The assay for ZnSO4 tablets involves time-consuming steps that contain mathematical formulae prone to calculation errors. To achieve consistency, save costs, and improve data integrity, validated spreadsheets were developed to simplify the two critical steps in the analysis of ZnSO4 tablets: standardization of 0.1M Sodium Edetate (EDTA) solution, and the complexometric titration assay procedure. The assay method in the United States Pharmacopoeia was used to create a process flow for ZnSO4 tablets. For each step in the process, different formulae were input into two spreadsheets to automate calculations. Further checks were created within the automated system to ensure validity of replicate analysis in titrimetric procedures. Validations were conducted using five data sets of manually computed assay results. The acceptance criteria set for the protocol were met. Significant p-values (p < 0.05, α = 0.05, at 95% Confidence Interval) were obtained from students’ t-test evaluation of the mean values for manual-calculated and spreadsheet results at all levels of the analysis flow. Right-first-time analysis and principles of data integrity were enhanced by use of the validated spreadsheet calculators in titrimetric evaluations of ZnSO4 tablets. Human errors were minimized in calculations when procedures were automated in quality control laboratories. The assay procedure for the formulation was achieved in a time-efficient manner with greater level of accuracy. This project is expected to promote cost savings for laboratory business models.Keywords: data integrity, spreadsheets, titrimetry, validation, zinc sulphate tablets
Procedia PDF Downloads 16913410 Antistress Effects of Hydrangeae Dulcis Folium on Net Handing Stress-Induced Anxiety-Like Behavior in Zebrafish: Possible Mechanism of Action of Adrenocorticotropin Hormone (ACTH) Receptor
Authors: Lee Seungheon, Kim Ba-Ro
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In this study, the anti-stress effects of the ethanolic extract of Hydrangeae Dulcis Folium (EHDF) were investigated. To determine the effects of EHDF on physical stress, changes in the whole-body cortisol level and behaviour were monitored in zebrafish. To induce physical stress, we used the net handling stress (NHS). Fish were treated with EHDF for 6 min before they were exposed to stress, and the fish were either evaluated via behavioural tests, including a novel tank test and an open field test or sacrificed to collect body fluid from the whole body. The results indicate that increased anxiety-like behaviours in the novel tank test and open field test under stress were recovered by treatment with EHDF at 5, 10 and 20 mg/L (P < 0.05). Moreover, compared with the normal group, which was not treated with NHS, the whole-body cortisol level was significantly increased by treatment with NHS in the control group. Compared with the control group, pre-treatment with EHDF at concentrations of 5, 10 and 20 mg/L for 6 min significantly prevented the increase in the whole-body cortisol level induced by NHS (P < 0.05). In addition, adrenocorticotropin hormone (ACTH) challenge studies showed that EHDF completely blocked the effects of ACTH (0.2 IU/g, IP) on cortisol secretion. These results suggest that EHDF may be a good anti-stress candidate and that its mechanism of action may be related to its positive effects on cortisol release.Keywords: net handling stress, zebrafish, hydrangeae dulcis folium, whole-body cortisol, novel tank test, open field test
Procedia PDF Downloads 29913409 System Identification of Timber Masonry Walls Using Shaking Table Test
Authors: Timir Baran Roy, Luis Guerreiro, Ashutosh Bagchi
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Dynamic study is important in order to design, repair and rehabilitation of structures. It has played an important role in the behavior characterization of structures; such as bridges, dams, high-rise buildings etc. There had been a substantial development in this area over the last few decades, especially in the field of dynamic identification techniques of structural systems. Frequency Domain Decomposition (FDD) and Time Domain Decomposition are most commonly used methods to identify modal parameters; such as natural frequency, modal damping, and mode shape. The focus of the present research is to study the dynamic characteristics of typical timber masonry walls commonly used in Portugal. For that purpose, a multi-storey structural prototypes of such walls have been tested on a seismic shake table at the National Laboratory for Civil Engineering, Portugal (LNEC). Signal processing has been performed of the output response, which is collected from the shaking table experiment of the prototype using accelerometers. In the present work signal processing of the output response, based on the input response has been done in two ways: FDD and Stochastic Subspace Identification (SSI). In order to estimate the values of the modal parameters, algorithms for FDD are formulated, and parametric functions for the SSI are computed. Finally, estimated values from both the methods are compared to measure the accuracy of both the techniques.Keywords: frequency domain decomposition (fdd), modal parameters, signal processing, stochastic subspace identification (ssi), time domain decomposition
Procedia PDF Downloads 26413408 Development of a Table-Top Composite Wire Fabrication System for Additive Manufacturing
Authors: Krishna Nand, Mohammad Taufik
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Fused Filament Fabrication (FFF) is one of the most popular additive manufacturing (AM) technology. In FFF technology, a wire form material (filament) is fed inside a heated chamber, where it gets converted into semi-solid form and extruded out of a nozzle to be deposited on the build platform to fabricate the part. FFF technology is expanding and covering the market at a very rapid rate, so the need of raw materials for 3D printing is also increasing. The cost of 3D printing is directly affected by filament cost. To make 3D printing more economic, a compact and portable filament/wire extrusion system is needed. Wire extrusion systems to extrude ordinary wire/filament made of a single material are available in the market. However, extrusion system to make a composite wire/filament are not available. Hence, in this study, initial efforts have been made to develop a table-top composite wire extruder. The developed system is consisted of mechanical parts, electronics parts, and a control system. A multiple channel hopper, extrusion screw, melting chamber and nozzle, cooling zone, and spool winder are some mechanical parts. While motors, heater, temperature sensor, cooling fans are some electronics parts, which are used to develop this system. A control board has been used to control the various process parameters like – temperature and speed of motors. For the production of composite wire/filament, two different materials could be fed through two channels of hopper, which will be mixed and carried to the heated zone by extrusion screw. The extrusion screw is rotated by a motor, and the speed of this motor will be controlled by the controller as per the requirement of material extrusion rate. In the heated zone, the material will melt with the help of a heating element and extruded out of the nozzle in the form of wire. The developed system occupies less floor space due to the vertical orientation of its heating chamber. It is capable to extrude ordinary filament as well as composite filament, which are compatible with 3D printers available in the market. Further, the developed system could be employed in the research and development of materials, processing, and characterization for 3D printer. The developed system presented in this study could be a better choice for hobbyists and researchers dealing with the fused filament fabrication process to reduce the 3D printing cost significantly by recycling the waste material into 3D printer feed material. Further, it could also be explored as a better alternative for filament production at the commercial level.Keywords: additive manufacturing, 3D Printing, filament extrusion, pellet extrusion
Procedia PDF Downloads 16813407 A Faunistic Study of Tetranychid and Phytoseiid Mites Associated with Diverse Crops From Samsun, Turkey
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This research was implemented from March to September to reveal tetranychid and phytoseiid mites on different field crops in Samsun province, Turkey. In consequence of microscope slide-mounting of mite samples in Hoyer’s medium, a total of six species belonging to Tetranychidae and fourteen species belonging to Phytoseiidae were found. Tetranychus urticae Koch, Tetranychus turkestani Ugarov and Nikolski, Tetranychus viennensis Zacher, Panonychus ulmi (Koch), Panonychus citri (Mc Gregor) and Bryobia rubrioculus (Scheuten) were detected as phytophaous mites. Euseius finlandicus (Oudemans), Kampimodromus aberrans (Oudemans), Amblyseius agrestris (Karg), Amblyseius andersoni (Chant), Amblyseius bicaudus Wainstein, Amblyseius zwölferi (Dosse), Amblyseius barkeri (Hughes), Paraseilus soleiger (Ribaga), Anthoseius recki (Wainstein), Phytoseius finitimus Ribaga, Typhlodromus pyri Scheuten, Typhloctonus tiliarum Oudemans, Phytoseiulus macropilis (Banks) and Phytoseiulus persimilis Athias-Henriot were identified to be predatory mites in Phytoseiidae. Among the phytoseiid species Kampimodromus aberrans, Amblyseius andersoni, Anthoseius recki, Phytoseius finitimus, Phytoseiulus persimilis and Phytoseiulus macropilis were widespread. Relationship between tetranychid and phytoseiid mites on different crops that can make considerable contribution to biological control in integrated pest management (IPM) programs is also reported.Keywords: biological control, IPM, interaction, phytoseiidae, tetranychidae
Procedia PDF Downloads 15513406 Satellites and Drones: Integrating Two Systems for Monitoring Air Quality and the Stress of the Plants
Authors: Bernabeo R. Alberto
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Unmanned aerial vehicles (UAV) platforms or remotely piloted aircraft system (Rpas) - with dedicated sensors - are fundamental support to the planning, running, and control of the territory in which public safety is or may be at risk for post-disaster assessments such as flooding or landslides, for searching lost people, for crime and accident scene photography, for assisting traffic control at major events, for teaching geography, history, natural science and all those subjects that require a continuous cyclical process of observation, evaluation and interpretation. Through the use of proximal remote sensing information related to anthropic landscape and nature integration, there is an opportunity to improve knowledge and management decision-making for the safeguarding of the environment, for farming, wildlife management, land management, mapping, glacier monitoring, atmospheric monitoring, for the conservation of archeological, historical, artistic and architectural sites, allowing an exact delimitation of the site in the territory. This paper will go over many different mission types. Within each mission type, it will give a broad overview to familiarize the reader but not make them an expert. It will also give detailed information on the payloads and other testing parameters the Unmanned Aerial Vehicles (UAV) use to complete a mission. The project's goal is to improve satellite maps about the stress of the plants, air quality monitoring, and related health issues.Keywords: proximal remote sensing, remotely piloted aircraft system, risk, safety, unmanned aerial vehicle
Procedia PDF Downloads 2213405 Managing Organizational Change for a Transformation Project: The Billing and Customer Relationship Management Journey
Authors: Sharifah I. N. A. Syed Azmi, Nazarina Mohd Nasir
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The Billing & Customer Relationship Management (BCRM) project is an important enabler towards realizing customer experience transformation. It involves technological shifts for future scalability, revision of multiple business processes and adoption of change by the users and impacted employees. This massive transition, if not managed properly, may result in the decline of business performance due to productivity drop. Organizational change management is an essential element in BCRM project implementation to ensure the system is well understood and embraced by all stakeholders. In order to move impacted employees from unaware state or denial mode to full-acceptance mindset and committing themselves in using the new system, their involvement in the whole change process starting from the initial stage is imperative. Through the BCRM Change Management Plan, a holistic approach was taken whereby the strategy and program for five key components namely executive sponsorship, continuous communication, process change readiness, organizational readiness and individual readiness were all carefully established. Roles of the project sponsor, change agents, change ambassadors and community of practice (CoP) were clearly defined in gaining high commitment and support across the entire organization. Continuous communication and engagement initiatives throughout project implementation have been carried out to reach all stakeholders. The business readiness was constantly monitored and assessed including effectiveness of end-user training, thorough review of process documentation and completion of roles realignment exercise.Keywords: BCRM, change management, organizational change, transformation project
Procedia PDF Downloads 14113404 The Regulation of Alternative Dispute Resolution Institutions in Consumer Redress and Enforcement: A South African Perspective
Authors: Jacolien Barnard, Corlia Van Heerden
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Effective and accessible consensual dispute resolution and in particular alternative dispute resolution, are central to consumer protection legislation. In this regard, the Consumer Protection Act 68 of 2008 (CPA) of South Africa is no exception. Due to the nature of consumer disputes, alternative dispute resolution (in theory) is an effective vehicle for the adjudication of disputes in a timely manner avoiding overburdening of the courts. The CPA sets down as one of its core purposes the provision of ‘an accessible, consistent, harmonized, effective and efficient system of redress for consumers’ (section 3(1)(h) of the CPA). Section 69 of the Act provides for the enforcement of consumer rights and provides for the National Consumer Commission to be the Central Authority which streamlines, adjudicates and channels disputes to the appropriate forums which include Alternative Dispute Resolution Agents (ADR-agents). The purpose of this paper is to analyze the regulation of these enforcement and redress mechanisms with particular focus on the Central Authority as well as the ADR-agents and their crucial role in successful and efficient adjudication of disputes in South Africa. The South African position will be discussed comparatively with the European Union (EU) position. In this regard, the European Union (EU) Directive on Alternative Dispute Resolution for Consumer Disputes (2013/11/EU) will be discussed (The ADR Directive). The aim of the ADR Directive is to solve contractual disputes between consumers and traders (suppliers or businesses) regardless of whether the agreement was concluded offline or online or whether or not the trader is situated in another member state (Recitals 4-6). The ADR Directive provides for a set of quality requirements that an ADR body or entity tasked with resolving consumer disputes should adhere to in member states which include regulatory mechanisms for control. Transparency, effectiveness, fairness, liberty and legality are all requirements for a successful ADR body and discussed within this chapter III of the Directive. Chapters III and IV govern the importance of information and co-operation. This includes information between ADR bodies and the European Commission (EC) but also between ADR bodies or entities and national authorities enforcing legal acts on consumer protection and traders. (In South Africa the National Consumer Tribunal, Provincial Consumer Protectors and Industry ombuds come to mind). All of which have a responsibility to keep consumers informed. Ultimately the papers aims to provide recommendations as to the successfulness of the current South African position in light of the comparative position in Europe and the highlight the importance of proper regulation of these redress and enforcement institutions.Keywords: alternative dispute resolution, consumer protection law, enforcement, redress
Procedia PDF Downloads 23313403 Governance and Financial Constraints the Impact on Corporate Social Responsibility Implementation in Cooperatives
Authors: Wanlapha Phraibueng, Patrick Sentis, Geraldine Riviere-Giordano
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Corporate Social Responsibility (CSR) initiatives have been widely discussed especially in investor-oriented firms. In contrast, cooperatives pay less attention to CSR because their activities have integrated the responsibility and the solidity of social, economic and environment. On the other hand, by adopting ownership theory and agency theory – cooperatives ignore CSR investment due to unclarified decision control in the governance and the limitation to acquire the capital financed. The unique governance and financial structures in cooperatives lead to the conflict among the stakeholders and long-term investment which have an impact on firm financial performance. As an illustration of cooperatives dilemmas, we address the question of Whether or not cooperatives in term of governance and financial structures are the constraints on implementing CSR policies. We find that the governance and financial structures in large cooperatives are the influence factors which predispose cooperatives to invest on CSR. In contrast, in the startup or small cooperatives, its governance and financial structures are the constraints on implementing CSR policies. We propose the alternative financial structure based on the trade-off between debt and equity which aims to relax the restrictions in cooperatives’ governance and allow cooperatives to acquire the capital financed either from its members or non-members. We suggest that engaging equity as a financial structure induces cooperatives to invest on CSR policies. Alternative financial structure eliminates not only cooperative ownership control problem but also the constraints in capital acquisition. By implementing CSR activities consistent with the alternative financial choice, cooperatives can increase firm’s value and reduce the conflict among their stakeholders.Keywords: cooperatives, corporate social responsibility, financial, governance
Procedia PDF Downloads 13913402 Investigation on Single Nucleotide Polymorphism in Candidate Genes and Their Association with Occurrence of Mycobacterium avium Subspecies Paratuberculosis Infection in Cattle
Authors: Ran Vir Singh, Anuj Chauhan, Subhodh Kumar, Rajesh Rathore, Satish Kumar, B Gopi, Sushil Kumar, Tarun Kumar, Ramji Yadav, Donna Phangchopi, Shoor Vir Singh
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Paratuberculosis caused by Mycobacterium avium subspecies paratuberculosis (MAP) is a chronic granulomatous enteritis affecting ruminants. It is responsible for significant economic losses in livestock industry worldwide. This organism is also of public health concern due to an unconfirmed link to Crohn’s disease. Susceptibility to paratuberculosis has been suggested to have genetic component with low to moderate heritability. Number of SNPs in various candidates genes have been observed to be affecting the susceptibility toward paratuberculosis. The objective of this study was to explore the association of various SNPs in the candidate genes and QTL region with MAP. A total of 117 SNPs from SLC11A1, IFNG, CARD15, TLR2, TLR4, CLEC7A, CD209, SP110, ANKARA2, PGLYRP1 and one QTL were selected for study. A total of 1222 cattle from various organized herds, gauhsalas and farmer herds were screened for MAP infection by Johnin intradermal skin test, AGID, serum ELISA, fecal microscopy, fecal culture and IS900 blood PCR. Based on the results of these tests, a case and control population of 200 and 183 respectively was established for study. A total of 117 SNPs from 10 candidate genes and one QTL were selected and validated/tested in our case and control population by PCR-RFLP technique. Data was analyzed using SAS 9.3 software. Statistical analysis revealed that, 107 out of 117 SNPs were not significantly associated with occurrence of MAP. Only SNP rs55617172 of TLR2, rs8193046 and rs8193060 of TLR4, rs110353594 and rs41654445 of CLEC7A, rs208814257of CD209, rs41933863 of ANKRA2, two loci {SLC11A1(53C/G)} and {IFNG (185 G/r) } and SNP rs41945014 in QTL region was significantly associated with MAP. Six SNP from 10 significant SNPs viz., rs110353594 and rs41654445 from CLEC7A, rs8193046 and rs8193060 from TLR4, rs109453173 from SLC11A1 rs208814257 from CD209 were validated in new case and control population. Out of these only one SNP rs8193046 of TLR4 gene was found significantly associated with occurrence of MAP in cattle. ODD ratio indicates that animals with AG genotype were more susceptible to MAP and this finding is in accordance with the earlier report. Hence it reaffirms that AG genotype can serve as a reliable genetic marker for indentifying more susceptible cattle in future selection against MAP infection in cattle.Keywords: SNP, candidate genes, paratuberculosis, cattle
Procedia PDF Downloads 35813401 Integrating Life Skills Education for Mental Health and Academic Benefits of Adolescents in Schools in Schools
Authors: Sarwat Sultan, Muhammad Saleem, Frasat Kanwal
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Adolescence is a transition period of life that brings physical and psychological changes and always results in several challenges for an adolescent. An adolescent must learn life skills for a healthy transition from adolescence period to adulthood. Therefore this study was planned to examine the effects of life skill education on adolescents' mental health and academic benefits. A random sample of 720 school students aged between 13-17 years was categorized into two groups; experimental (n=360) and control (n=360). Life skill education was given to the students of the intervention group with repeated assessments of mental health and academic benefits at pre-intervention (T1) and post-intervention (T2) for both groups. Both groups were compared on scores of mental health and academic benefits across two times T1 and T2 by employing a mixed between-within-subjects analysis of variance. Findings showed the main effect of time suggesting the largest changes in mental health and academic benefits over time. Interaction effects between time and both groups were also found significant indicating the largest changes across time between both groups. Results of between-group comparisons showed significant values for Wilks’ Lambda and partial eta squared for students of the intervention group who scored higher on mental health and academic benefits after receiving life skills training than the students of the control group. Results of the present study determined the efficacy of life skill education and have implications for both teachers and psychotherapists to improve the students’ mental health and academic performance.Keywords: academic benefits, life skills, mental health, adolescents
Procedia PDF Downloads 5613400 Spectrophotometric Determination of Phenylephrine Hydrochloride by Coupling with Diazotized 2,4-Dinitroaniline
Authors: Sulaiman Gafar Muhamad
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A rapid spectrophotometric method for the micro-determination of phenylephrine-HCl (PHE) has been developed. The proposed method involves the coupling of phenylephrine-HCl with diazotized 2,4-dinitroaniline in alkaline medium at λmax 455 nm. Under the present optimum condition, Beer’s law was obeyed in the range of 1.0-20 μg/ml of PHE with molar absorptivity of 1.915 ×104 l. mol-1.cm-1, with a relative error of 0.015 and a relative standard deviation of 0.024%. The current method has been applied successfully to estimate phenylephrine-HCl in pharmaceutical preparations (nose drop and syrup).Keywords: diazo-coupling, 2, 4-dinitroaniline, phenylephrine-HCl, spectrophotometry
Procedia PDF Downloads 25713399 Microbial Fuel Cells: Performance and Applications
Authors: Andrea Pietrelli, Vincenzo Ferrara, Bruno Allard, Francois Buret, Irene Bavasso, Nicola Lovecchio, Francesca Costantini, Firas Khaled
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This paper aims to show some applications of microbial fuel cells (MFCs), an energy harvesting technique, as clean power source to supply low power device for application like wireless sensor network (WSN) for environmental monitoring. Furthermore, MFC can be used directly as biosensor to analyse parameters like pH and temperature or arranged in form of cluster devices in order to use as small power plant. An MFC is a bioreactor that converts energy stored in chemical bonds of organic matter into electrical energy, through a series of reactions catalysed by microorganisms. We have developed a lab-scale terrestrial microbial fuel cell (TMFC), based on soil that acts as source of bacteria and flow of nutrient and a lab-scale waste water microbial fuel cell (WWMFC), where waste water acts as flow of nutrient and bacteria. We performed large series of tests to exploit the capability as biosensor. The pH value has strong influence on the open circuit voltage (OCV) delivered from TMFCs. We analyzed three condition: test A and B were filled with same soil but changing pH from 6 to 6.63, test C was prepared using a different soil with a pH value of 6.3. Experimental results clearly show how with higher pH value a higher OCV was produced; indeed reactors are influenced by different values of pH which increases the voltage in case of a higher pH value until the best pH value of 7 is achieved. The influence of pH on OCV of lab-scales WWMFC was analyzed at pH value of 6.5, 7, 7.2, 7.5 and 8. WWMFCs are influenced from temperature more than TMFCs. We tested the power performance of WWMFCs considering four imposed values of ambient temperature. Results show how power performance increase proportionally with higher temperature values, doubling the output power from 20° to 40°. The best value of power produced from our lab-scale TMFC was equal to 310 μW using peaty soil, at 1KΩ, corresponding to a current of 0.5 mA. A TMFC can supply proper energy to low power devices of a WSN by means of the design of three stages scheme of an energy management system, which adapts voltage level of TMFC to those required by a WSN node, as 3.3V. Using a commercial DC/DC boost converter, that needs an input voltage of 700 mV, the current source of 0.5 mA, charges a capacitor of 6.8 mF until it will have accumulated an amount of charge equal to 700 mV in a time of 10 s. The output stage includes an output switch that close the circuit after a time of 10s + 1.5ms because the converter can boost the voltage from 0.7V to 3.3V in 1.5 ms. Furthermore, we tested in form of clusters connected in series up to 20 WWMFCs, we have obtained a high voltage value as output, around 10V, but low current value. MFC can be considered a suitable clean energy source to be used to supply low power devices as a WSN node or to be used directly as biosensor.Keywords: energy harvesting, low power electronics, microbial fuel cell, terrestrial microbial fuel cell, waste-water microbial fuel cell, wireless sensor network
Procedia PDF Downloads 20713398 A Three Elements Vector Valued Structure’s Ultimate Strength-Strong Motion-Intensity Measure
Authors: A. Nicknam, N. Eftekhari, A. Mazarei, M. Ganjvar
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This article presents an alternative collapse capacity intensity measure in the three elements form which is influenced by the spectral ordinates at periods longer than that of the first mode period at near and far source sites. A parameter, denoted by β, is defined by which the spectral ordinate effects, up to the effective period (2T_1), on the intensity measure are taken into account. The methodology permits to meet the hazard-levelled target extreme event in the probabilistic and deterministic forms. A MATLAB code is developed involving OpenSees to calculate the collapse capacities of the 8 archetype RC structures having 2 to 20 stories for regression process. The incremental dynamic analysis (IDA) method is used to calculate the structure’s collapse values accounting for the element stiffness and strength deterioration. The general near field set presented by FEMA is used in a series of performing nonlinear analyses. 8 linear relationships are developed for the 8structutres leading to the correlation coefficient up to 0.93. A collapse capacity near field prediction equation is developed taking into account the results of regression processes obtained from the 8 structures. The proposed prediction equation is validated against a set of actual near field records leading to a good agreement. Implementation of the proposed equation to the four archetype RC structures demonstrated different collapse capacities at near field site compared to those of FEMA. The reasons of differences are believed to be due to accounting for the spectral shape effects.Keywords: collapse capacity, fragility analysis, spectral shape effects, IDA method
Procedia PDF Downloads 23913397 Preliminary Analysis for Oil and Gas Geological Characteristics and Exploration Prospects of Doseo Basin in Central Africa
Authors: Haiqiang Song, Huiqing Liu
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The Doseo basin in Chad, Central Africa is one of the most important oil and gas blocks in the world. However, the low degree of oil and gas exploration and the lack of relevant geological data restrict the understanding and resource evaluation of the basin. To further develop the Doseo basin efficiently, it is urgent to deeply analyze the source rock characteristics and hydrocarbon generation potential of the Doseo basin. Based on seismic and drilling data in recent years, this paper systematically evaluates the geochemical characteristics of source rocks and their generated oils in Doseo Basin, explores the development, distribution, and evolution characteristics of source rocks, and evaluates the exploration potential of Doseo Basin according to the hydrocarbon enrichment law. The results show that the Lower Cretaceous Baliemian and Apudian source rocks in Doseo Basin are well developed, with high organic matter abundance (average TOC≥3%) and good organic matter types (type I~II), which are the main development layers of source rocks, but the organic matter maturity is generally low (Ro of the drilled source rocks is mainly between 0.4%~0.8%). The planar structure also shows that the main hydrocarbon accumulation mode in Doseo sag is the forward tectonic reservoirs such as near source anticlines and faulted noses. Finally, it is estimated that the accumulative resources of the main source rocks in the Doseo Basin are about 4.33× 108T in Apudite and Balim terrace layers. The results of this study will help guide the next step of oil and gas exploration, which is expected to drive the next step of oil and gas development.Keywords: Doseo basin, lower cretaceous, source rock characteristics, developmental characteristics, hydrocarbon generation potential
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