Search results for: response history analysis
31006 Analysis of Structural Modeling on Digital English Learning Strategy Use
Authors: Gyoomi Kim, Jiyoung Bae
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The purpose of this study was to propose a framework that verifies the structural relationships among students’ use of digital English learning strategy (DELS), affective domains, and their individual variables. The study developed a hypothetical model based on previous studies on language learning strategy use as well as digital language learning. The participants were 720 Korean high school students and 430 university students. The instrument was a self-response questionnaire that contained 70 question items based on Oxford’s SILL (Strategy Inventory for Language Learning) as well as the previous studies on language learning strategies in digital learning environment in order to measure DELS and affective domains. The collected data were analyzed through structural equation modeling (SEM). This study used quantitative data analysis procedures: Explanatory factor analysis (EFA) and confirmatory factor analysis (CFA). Firstly, the EFA was conducted in order to verify the hypothetical model; the factor analysis was conducted preferentially to identify the underlying relationships between measured variables of DELS and the affective domain in the EFA process. The hypothetical model was established with six indicators of learning strategies (memory, cognitive, compensation, metacognitive, affective, and social strategies) under the latent variable of the use of DELS. In addition, the model included four indicators (self-confidence, interests, self-regulation, and attitude toward digital learning) under the latent variable of learners’ affective domain. Secondly, the CFA was used to determine the suitability of data and research models, so all data from the present study was used to assess model fits. Lastly, the model also included individual learner factors as covariates and five constructs selected were learners’ gender, the level of English proficiency, the duration of English learning, the period of using digital devices, and previous experience of digital English learning. The results verified from SEM analysis proposed a theoretical model that showed the structural relationships between Korean students’ use of DELS and their affective domains. Therefore, the results of this study help ESL/EFL teachers understand how learners use and develop appropriate learning strategies in digital learning contexts. The pedagogical implication and suggestions for the further study will be also presented.Keywords: Digital English Learning Strategy, DELS, individual variables, learners' affective domains, Structural Equation Modeling, SEM
Procedia PDF Downloads 12831005 Scour Damaged Detection of Bridge Piers Using Vibration Analysis - Numerical Study of a Bridge
Authors: Solaine Hachem, Frédéric Bourquin, Dominique Siegert
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The brutal collapse of bridges is mainly due to scour. Indeed, the soil erosion in the riverbed around a pier modifies the embedding conditions of the structure, reduces its overall stiffness and threatens its stability. Hence, finding an efficient technique that allows early scour detection becomes mandatory. Vibration analysis is an indirect method for scour detection that relies on real-time monitoring of the bridge. It tends to indicate the presence of a scour based on its consequences on the stability of the structure and its dynamic response. Most of the research in this field has focused on the dynamic behavior of a single pile and has examined the depth of the scour. In this paper, a bridge is fully modeled with all piles and spans and the scour is represented by a reduction in the foundation's stiffnesses. This work aims to identify the vibration modes sensitive to the rigidity’s loss in the foundations so that their variations can be considered as a scour indicator: the decrease in soil-structure interaction rigidity leads to a decrease in the natural frequencies’ values. By using the first-order perturbation method, the expression of sensitivity, which depends only on the selected vibration modes, is established to determine the deficiency of foundations stiffnesses. The solutions are obtained by using the singular value decomposition method for the regularization of the inverse problem. The propagation of uncertainties is also calculated to verify the efficiency of the inverse problem method. Numerical simulations describing different scenarios of scour are investigated on a simplified model of a real composite steel-concrete bridge located in France. The results of the modal analysis show that the modes corresponding to in-plane and out-of-plane piers vibrations are sensitive to the loss of foundation stiffness. While the deck bending modes are not affected by this damage.Keywords: bridge’s piers, inverse problems, modal sensitivity, scour detection, vibration analysis
Procedia PDF Downloads 11331004 BiFeO3-CoFe2O4-PbTiO3 Composites: Structural, Multiferroic and Optical Characteristics
Authors: Nidhi Adhlakha, K. L. Yadav
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Three phase magnetoelectric (ME) composites (1-x)(0.7BiFeO3-0.3CoFe2O4)-xPbTiO3 (or equivalently written as (1-x)(0.7BFO-0.3CFO)-xPT) with x variations 0, 0.30, 0.35, 0.40, 0.45 and 1.0 were synthesized using hybrid processing route. The effects of PT addition on structural, multiferroic and optical properties have been subsequently investigated. A detailed Rietveld refinement analysis of X-ray diffraction patterns has been performed, which confirms the presence of structural phases of individual constituents in the composites. Field emission scanning electron microscopy (FESEM) images are taken for microstructural analysis and grain size determination. Transmission electron microscopy (TEM) analysis of 0.3CFO-0.7BFO reveals the average particle size to be lying in the window of 8-10 nm. The temperature dependent dielectric constant at various frequencies (1 kHz, 10 kHz, 50 kHz, 100 kHz and 500 kHz) has been studied and the dielectric study reveals that the increase of dielectric constant and decrease of average dielectric loss of composites with incorporation of PT content. The room temperature ferromagnetic behavior of composites is confirmed through the observation of Magnetization vs. Magnetic field (M-H) hysteresis loops. The variation of magnetization with temperature indicates the presence of spin glass behavior in composites. Magnetoelectric coupling is evidenced in the composites through the observation of the dependence of the dielectric constant on the magnetic field, and magnetodielectric response of 2.05 % is observed for 45 mol% addition of PT content. The fractional change of magnetic field induced dielectric constant can also be expressed as ∆ε_r~γM^2 and the value of γ is found to be ~1.08×10-2 (emu/g)-2 for composite with x=0.40. Fourier transformed infrared (FTIR) spectroscopy of samples is carried out to analyze various bonds formation in the composites.Keywords: composite, X-ray diffraction, dielectric properties, optical properties
Procedia PDF Downloads 31331003 Fiber-Optic Sensors for Hydrogen Peroxide Vapor Measurement
Authors: H. Akbari Khorami, P. Wild, N. Djilali
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This paper reports on the response of a fiber-optic sensing probe to small concentrations of hydrogen peroxide (H2O2) vapor at room temperature. H2O2 has extensive applications in industrial and medical environments. Conversely, H2O2 can be a health hazard by itself. For example, H2O2 induces cellular damage in human cells and its presence can be used to diagnose illnesses such as asthma and human breast cancer. Hence, development of reliable H2O2 sensor is of vital importance to detect and measure this species. Ferric ferrocyanide, referred to as Prussian blue (PB), was deposited on the tip of a multimode optical fiber through the single source precursor technique and served as an indicator of H2O2 in a spectroscopic manner. Sensing tests were performed in H2O2-H2O vapor mixtures with different concentrations of H2O2. The results of sensing tests show the sensor is able to detect H2O2 concentrations in the range of 50.6 ppm to 229.5 ppm. Furthermore, the sensor response to H2O2 concentrations is linear in a log-log scale with the adjacent R-square of 0.93. This sensing behavior allows us to detect and quantify the concentration of H2O2 in the vapor phase.Keywords: chemical deposition, fiber-optic sensor, hydrogen peroxide vapor, prussian blue
Procedia PDF Downloads 36231002 Optimization of Parameters for Electrospinning of Pan Nanofibers by Taguchi Method
Authors: Gamze Karanfil Celep, Kevser Dincer
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The effects of polymer concentration and electrospinning process parameters on the average diameters of electrospun polyacrylonitrile (PAN) nanofibers were experimentally investigated. Besides, mechanical and thermal properties of PAN nanofibers were examined by tensile test and thermogravimetric analysis (TGA), respectively. For this purpose, the polymer concentration, solution feed rate, supply voltage and tip-to-collector distance were determined as the control factors. To succeed these aims, Taguchi’s L16 orthogonal design (4 parameters, 4 level) was employed for the experimental design. Optimal electrospinning conditions were defined using the signal-to-noise (S/N) ratio that was calculated from diameters of the electrospun PAN nanofibers according to "the-smaller-the-better" approachment. In addition, analysis of variance (ANOVA) was evaluated to conclude the statistical significance of the process parameters. The smallest diameter of PAN nanofibers was observed. According to the S/N ratio response results, the most effective parameter on finding out of nanofiber diameter was determined. Finally, the Taguchi design of experiments method has been found to be an effective method to statistically optimize the critical electrospinning parameters used in nanofiber production. After determining the optimum process parameters of nanofiber production, electrical conductivity and fuel cell performance of electrospun PAN nanofibers on the carbon papers will be evaluated.Keywords: nanofiber, electrospinning, polyacrylonitrile, Taguchi method
Procedia PDF Downloads 20931001 Islam, Gender and Education in Contemporary Georgia: The Example of Kvemo Kartli
Authors: N. Gelovani, D. Ismailov, S. Bochorishvili
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Religious minorities of Georgia include Muslims. Their composition is sufficiently miscellaneous, enclosing both ethnical viewpoint and belonging to the inner Islamic denomination. A majority of Muslims represent Azerbaijanis, who chiefly live in Kvemo Kartli (Bolnisi, Gardabani, Dmanisi, Tetri Tskaro, Marneuli and Tsalka). The catalyst for researchers of Islamic History is the geopolitical interests of Georgia, centuries-old contacts with the Islamic world, the not entirely trivial portion of Islam confessor population, the increasing influence of the Islamic factor in current religious-political processes in the world, the elevating procedure of Muslim religious self-consciousness in the Post-Soviet states, significant challenges of international terrorism, and perspectives of rapid globalization. The rise in the level of religious identity of Muslim citizens of Georgia (first of all of those who are not ethnic Georgians) is noticeable. New mosques have been constructed and, sometimes, even young people are being sent to the religious educational institutions of Muslim countries to gain a higher Islamic education. At a time when gender studies are substantive, the goal of which is to eliminate gender-based discrimination and violence in societies, it is essential in Georgia to conduct researches around the concrete problem – Islamic tradition, woman and education in Georgia. A woman’s right to education is an important indicator of women’s general status in a society. The appropriate resources, innovative analysis of Georgian ethnological materials, and surveying of the population (quantitative and qualitative research reports, working papers), condition the success of these researches. In the presented work, interrelation matters of Islam, gender and education in contemporary Georgia by the example of the Azerbaijani population in Kvemo Kartli during period 1992-2016 are studied. We researched the history of Muslim religious education centers in Tbilisi and Kvemo Kartli (Bolnisi, Gardabani, Dmanisi, Tetri Tskaro, Marneuli and Tsalka) in 1992-2016, on the one hand, and the results of sociological interrogation, on the other. As a result of our investigation, we found that Azeri women in the Kvemo Kartli (Georgia) region mostly receive their education in Georgia and Azerbaijan. Educational and Cultural Institutions are inaccessible for most Azeri women. The main reasons are the absence of educational and religious institutions at their places of residence and state policies towards Georgia’s Muslims.Keywords: Islam, gender, Georgia, education
Procedia PDF Downloads 23031000 Mediterranean Diet, Duration of Admission and Mortality in Elderly, Hospitalized Patients: A Cross-Sectional Study
Authors: Christos Lampropoulos, Maria Konsta, Ifigenia Apostolou, Vicky Dradaki, Tamta Sirbilatze, Irini Dri, Christina Kordali, Vaggelis Lambas, Kostas Argyros, Georgios Mavras
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Objectives: Mediterranean diet has been associated with lower incidence of cardiovascular disease and cancer. The purpose of our study was to examine the hypothesis that Mediterranean diet may protect against mortality and reduce admission duration in elderly, hospitalized patients. Methods: Sample population included 150 patients (78 men, 72 women, mean age 80±8.2). The following data were taken into account in analysis: anthropometric and laboratory data, dietary habits (MedDiet score), patients’ nutritional status [Mini Nutritional Assessment (MNA) score], physical activity (International Physical Activity Questionnaires, IPAQ), smoking status, cause and duration of current admission, medical history (co-morbidities, previous admissions). Primary endpoints were mortality (from admission until 6 months afterwards) and duration of admission, compared to national guidelines for closed consolidated medical expenses. Logistic regression and linear regression analysis were performed in order to identify independent predictors for mortality and admission duration difference respectively. Results: According to MNA, nutrition was normal in 54/150 (36%) of patients, 46/150 (30.7%) of them were at risk of malnutrition and the rest 50/150 (33.3%) were malnourished. After performing multivariate logistic regression analysis we found that the odds of death decreased 30% per each unit increase of MedDiet score (OR=0.7, 95% CI:0.6-0.8, p < 0.0001). Patients with cancer-related admission were 37.7 times more likely to die, compared to those with infection (OR=37.7, 95% CI:4.4-325, p=0.001). According to multivariate linear regression analysis, admission duration was inversely related to Mediterranean diet, since it is decreased 0.18 days on average for each unit increase of MedDiet score (b:-0.18, 95% CI:-0.33 - -0.035, p=0.02). Additionally, the duration of current admission increased on average 0.83 days for each previous hospital admission (b:0.83, 95% CI:0.5-1.16, p<0.0001). The admission duration of patients with cancer was on average 4.5 days higher than the patients who admitted due to infection (b:4.5, 95% CI:0.9-8, p=0.015). Conclusion: Mediterranean diet adequately protects elderly, hospitalized patients against mortality and reduces the duration of hospitalization.Keywords: Mediterranean diet, malnutrition, nutritional status, prognostic factors for mortality
Procedia PDF Downloads 31630999 Visual Representation and the De-Racialization of Public Spaces
Authors: Donna Banks
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In 1998 Winston James called for more research on the Caribbean diaspora and this ethnographic study, incorporating participant observation, interviews, and archival research, adds to the scholarship in this area. The research is grounded in the discipline of cultural studies but is cross-disciplinary in nature, engaging anthropology, psychology, and urban planning. This paper centers on community murals and their contribution to a more culturally diverse and representative community. While many museums are in the process of reassessing their collection, acquiring works, and developing programming to be more inclusive, and public art programs are investing millions of dollars in trying to fashion an identity in which all residents can feel included, local artists in neighborhoods in many countries have been using community murals to tell their stories. Community murals serve a historical, political, and social purpose and are an instrumental strategy in creative placemaking projects. Community murals add to the livability of an area. Even though official measurements of livability do not include race, ethnicity, and gender - which are egregious omissions - murals are a way to integrate historically underrepresented people into the wider history of a country. This paper draws attention to a creative placemaking project in the port city of Bristol, England. A city, like many others, with a history of spacializing race and racializing space. For this reason, Bristol’s Seven Saints of St. Pauls® Art & Heritage Trail, which memorializes seven Caribbean-born social and political change agents, is examined. The Seven Saints of St. Pauls® Art & Heritage Trail is crucial to the city, as well as the country, in its contribution to the de-racialization of public spaces. Within British art history, with few exceptions, portraits of non-White people who are not depicted in a subordinate role have been absent. The artist of the mural project, Michelle Curtis, has changed this long-lasting racist and hegemonic narrative. By creating seven large-scale portraits of individuals not typically represented visually, the artist has added them into Britain’s story. In these murals, however, we see more than just the likeness of a person; we are presented with a visual commentary that reflects each Saint’s hybrid identity of being both Black Caribbean and British, as well as their social and political involvement. Additionally, because the mural project is part of a heritage trail, the murals' are therapeutic and contribute to improving the well-being of residents and strengthening their sense of belonging.Keywords: belonging, murals, placemaking, representation
Procedia PDF Downloads 9730998 Clinical Presentation and Immune Response to Intramammary Infection of Holstein-Friesian Heifers with Isolates from Two Staphylococcus aureus Lineages
Authors: Dagmara A. Niedziela, Mark P. Murphy, Orla M. Keane, Finola C. Leonard
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Staphylococcus aureus is the most frequent cause of clinical and subclinical bovine mastitis in Ireland. Mastitis caused by S. aureus is often chronic and tends to recur after antibiotic treatment. This may be due to several virulence factors, including attributes that enable the bacterium to internalize into bovine mammary epithelial cells, where it may evade antibiotic treatment, or evade the host immune response. Four bovine-adapted lineages (CC71, CC97, CC151 and ST136) were identified among a collection of Irish S. aureus mastitis isolates. Genotypic variation of mastitis-causing strains may contribute to different presentations of the disease, including differences in milk somatic cell count (SCC), the main method of mastitis detection. The objective of this study was to investigate the influence of bacterial strain and lineage on host immune response, by employing cell culture methods in vitro as well as an in vivo infection model. Twelve bovine adapted S. aureus strains were examined for internalization into bovine mammary epithelial cells (bMEC) and their ability to induce an immune response from bMEC (using qPCR and ELISA). In vitro studies found differences in a variety of virulence traits between the lineages. Strains from lineages CC97 and CC71 internalized more efficiently into bovine mammary epithelial cells (bMEC) than CC151 and ST136. CC97 strains also induced immune genes in bMEC more strongly than strains from the other 3 lineages. One strain each of CC151 and CC97 that differed in their ability to cause an immune response in bMEC were selected on the basis of the above in vitro experiments. Fourteen first-lactation Holstein-Friesian cows were purchased from 2 farms on the basis of low SCC (less than 50 000 cells/ml) and infection free status. Seven cows were infected with 1.73 x 102 c.f.u. of the CC97 strain (Group 1) and another seven with 5.83 x 102 c.f.u. of the CC151 strain (Group 2). The contralateral quarter of each cow was inoculated with PBS (vehicle). Clinical signs of infection (temperature, milk and udder appearance, milk yield) were monitored for 30 days. Blood and milk samples were taken to determine bacterial counts in milk, SCC, white blood cell populations and cytokines. Differences in disease presentation in vivo between groups were observed, with two animals from Group 2 developing clinical mastitis and requiring antibiotic treatment, while one animal from Group 1 did not develop an infection for the duration of the study. Fever (temperature > 39.5⁰C) was observed in 3 animals from Group 2 and in none from Group 1. Significant differences in SCC and bacterial load between groups were observed in the initial stages of infection (week 1). Data is also being collected on cytokines and chemokines secreted during the course of infection. The results of this study suggest that a strain from lineage CC151 may cause more severe clinical mastitis, while a strain from lineage CC97 may cause mild, subclinical mastitis. Diversity between strains of S. aureus may therefore influence the clinical presentation of mastitis, which in turn may influence disease detection and treatment needs.Keywords: Bovine mastitis, host immune response, host-pathogen interactions, Staphylococcus aureus
Procedia PDF Downloads 16030997 Analysis of Thermal Damping in Si Based Torsional Micromirrors
Authors: R. Resmi, M. R. Baiju
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The thermal damping of a dynamic vibrating micromirror is an important factor affecting the design of MEMS based actuator systems. In the development process of new micromirror systems, assessing the extent of energy loss due to thermal damping accurately and predicting the performance of the system is very essential. In this paper, the depth of the thermal penetration layer at different eigenfrequencies and the temperature variation distributions surrounding a vibrating micromirror is analyzed. The thermal penetration depth corresponds to the thermal boundary layer in which energy is lost which is a measure of the thermal damping is found out. The energy is mainly dissipated in the thermal boundary layer and thickness of the layer is an important parameter. The detailed thermoacoustics is used to model the air domain surrounding the micromirror. The thickness of the boundary layer, temperature variations and thermal power dissipation are analyzed for a Si based torsional mode micromirror. It is found that thermal penetration depth decreases with eigenfrequency and hence operating the micromirror at higher frequencies is essential for reducing thermal damping. The temperature variations and thermal power dissipations at different eigenfrequencies are also analyzed. Both frequency-response and eigenfrequency analyses are done using COMSOL Multiphysics software.Keywords: Eigen frequency analysis, micromirrors, thermal damping, thermoacoustic interactions
Procedia PDF Downloads 37030996 Valorisation of Mango Seed: Response Surface Methodology Based Optimization of Starch Extraction from Mango Seeds
Authors: Tamrat Tesfaye, Bruce Sithole
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Box-Behnken Response surface methodology was used to determine the optimum processing conditions that give maximum extraction yield and whiteness index from mango seed. The steeping time ranges from 2 to 12 hours and slurring of the steeped seed in sodium metabisulphite solution (0.1 to 0.5 w/v) was carried out. Experiments were designed according to Box-Behnken Design with these three factors and a total of 15 runs experimental variables of were analyzed. At linear level, the concentration of sodium metabisulphite had significant positive influence on percentage yield and whiteness index at p<0.05. At quadratic level, sodium metabisulphite concentration and sodium metabisulphite concentration2 had a significant negative influence on starch yield; sodium metabisulphite concentration and steeping time*temperature had significant (p<0.05) positive influence on whiteness index. The adjusted R2 above 0.8 for starch yield (0.906465) and whiteness index (0.909268) showed a good fit of the model with the experimental data. The optimum sodium metabisulphite concentration, steeping hours, and temperature for starch isolation with maximum starch yield (66.428%) and whiteness index (85%) as set goals for optimization with the desirability of 0.91939 was 0.255w/v concentration, 2hrs and 50 °C respectively. The determined experimental value of each response based on optimal condition was statistically in accordance with predicted levels at p<0.05. The Mango seeds are the by-products obtained during mango processing and possess disposal problem if not handled properly. The substitution of food based sizing agents with mango seed starch can contribute as pertinent resource deployment for value-added product manufacturing and waste utilization which might play significance role of food security in Ethiopia.Keywords: mango, synthetic sizing agent, starch, extraction, textile, sizing
Procedia PDF Downloads 23630995 Experimental Demonstration of an Ultra-Low Power Vertical-Cavity Surface-Emitting Laser for Optical Power Generation
Authors: S. Nazhan, Hassan K. Al-Musawi, Khalid A. Humood
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This paper reports on an experimental investigation into the influence of current modulation on the properties of a vertical-cavity surface-emitting laser (VCSEL) with a direct square wave modulation. The optical output power response, as a function of the pumping current, modulation frequency, and amplitude, is measured for an 850 nm VCSEL. We demonstrate that modulation frequency and amplitude play important roles in reducing the VCSEL’s power consumption for optical generation. Indeed, even when the biasing current is below the static threshold, the VCSEL emits optical power under the square wave modulation. The power consumed by the device to generate light is significantly reduced to > 50%, which is below the threshold current, in response to both the modulation frequency and amplitude. An operating VCSEL device at low power is very desirable for less thermal effects, which are essential for a high-speed modulation bandwidth.Keywords: vertical-cavity surface-emitting lasers, VCSELs, optical power generation, power consumption, square wave modulation
Procedia PDF Downloads 16830994 Seroprevalence and Associated Factors of Hepatitis B and Hepatitis C Viral Infections Among Prisoners in Tigray, Northern Ethiopia
Authors: Belaynesh Tsegay, Teklay Gebrecherkos, Atsebaha Gebrekidan Kahsay, Mahmud Abdulkader
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Background: Hepatitis B and C viruses are important health and socioeconomic problem across the globe, with a remarkable number of diseases and deaths in sub-Saharan African countries. The burden of hepatitis is unknown in the prison settings of Tigray. Therefore, we aimed to describe the seroprevalence and associated factors of hepatitis B and C viruses among prisoners in Tigray, Ethiopia. Methods: A cross-sectional study was carried out from February 2020 to May 2020 at the prison facilities of Tigray. Demographics and associated factors were collected from 315 prisoners prospectively. Five milliliters of blood were collected and tested using rapid tests kits of HBsAg (Zhejiang orient Gene Biotech Co., Ltd., China) and HCV antibodies (Volkan Kozmetik Sanayi Ve Ticaret Ltd. STI, Turkey). Positive samples were confirmed using ELISA (Beijing Wantai Biological Pharmacy Enterprise Co. Ltd). Data were analyzed using the SPSS version 20, and p<0.05 was considered statistically significant. Results: The overall seroprevalence of HBV and HCV were 25 (7.9%) and 1 (0.3%), respectively. The majority of hepatitis B viral infections were identified from the age groups of 18–25 years (10.7%) and unmarried prisoners (11.8%). Prisoners greater than 100 per cell (AOR=3.95, 95% CI=1.15–13.6, p=0.029) and with a history of alcohol consumption (AOR=3.01, 95% CI=1.17–7.74, p=0.022) were significantly associated with HBV infections. Conclusion: The seroprevalence of HBV among prisoners was nearly high or borderline, with a very low HCV prevalence. HBV was most prevalent among young adults, those housed with a large number of prisoners per cell, and those who had a history of alcohol consumption. This study recommends that there should be prison-focused intervention, including regular health education, with the emphasis on the mode of transmission and introducing HBV screening policy for prisoners, especially when they enter the prison.Keywords: seroprevalence, HBV, HCV, prisoners, tigray
Procedia PDF Downloads 9330993 Mediation Analysis of the Efficacy of the Nimotuzumab-Cisplatin-Radiation (NCR) Improve Overall Survival (OS): A HPV Negative Oropharyngeal Cancer Patient (HPVNOCP) Cohort
Authors: Akshay Patil
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Objective: Mediation analysis identifies causal pathways by testing the relationships between the NCR, the OS, and an intermediate variable that mediates the relationship between the Nimotuzumab-cisplatin-radiation (NCR) and OS. Introduction: In randomized controlled trials, the primary interest is in the mechanisms by which an intervention exerts its effects on the outcomes. Clinicians are often interested in how the intervention works (or why it does not work) through hypothesized causal mechanisms. In this work, we highlight the value of understanding causal mechanisms in randomized trial by applying causal mediation analysis in a randomized trial in oncology. Methods: Data was obtained from a phase III randomized trial (Subgroup of HPVNOCP). NCR is reported to significantly improve the OS of patients locally advanced head and neck cancer patients undergoing definitive chemoradiation. Here, based on trial data, the mediating effect of NCR on patient overall survival was systematically quantified through progression-free survival(PFS), disease free survival (DFS), Loco-regional failure (LRF), and the disease control rate (DCR), Overall response rate (ORR). Effects of potential mediators on the HR for OS with NCR versus cisplatin-radiation (CR) were analyzed by Cox regression models. Statistical analyses were performed using R software Version 3.6.3 (The R Foundation for Statistical Computing) Results: Effects of potential mediator PFS was an association between NCR treatment and OS, with an indirect-effect (IE) 0.76(0.62 – 0.95), which mediated 60.69% of the treatment effect. Taking into account baseline confounders, the overall adjusted hazard ratio of death was 0.64 (95% CI: 0.43 – 0.96; P=0.03). The DFS was also a significant mediator and had an IE 0.77 (95% CI; 0.62-0.93), 58% mediated). Smaller mediation effects (maximum 27%) were observed for LRF with IE 0.88(0.74 – 1.06). Both DCR and ORR mediated 10% and 15%, respectively, of the effect of NCR vs. CR on the OS with IE 0.65 (95% CI; 0.81 – 1.08) and 0.94(95% CI; 0.79 – 1.04). Conclusion: Our findings suggest that PFS and DFS were the most important mediators of the OS with nimotuzumab to weekly cisplatin-radiation in HPVNOCP.Keywords: mediation analysis, cancer data, survival, NCR, HPV negative oropharyngeal
Procedia PDF Downloads 14930992 Translators as Agents: Jewish Translators and Zsolnay Publishing House’s Translational Culture in Pre-Anschluss Austria,1924-1938
Authors: Tatsiana Haiden
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The role of the translator in the publishing process has been underestimated for centuries. Any translation is produced in a certain socio-political context by agents with different background, interests, and opinions, i.e., no translation is neutral. Any translation goes beyond the text; it is not only an interlingual transfer of signs but a social phenomenon. The case study shows how Jewish social networks influence publishing translations and aims to explain the unexpected success of the Jewish publishing house in pre-Anschluss Austria. The research shows that translators play a central role (‘Translator’s visibility’ - Pym, ‘Activist turn’ - Wolf, ‘Translator studies’ - Chesterman) in choosing what has to be translated and establishing communication between the author and the publisher. The concept of Translationskultur of Prunc is being historized and applied to the publishing house for the first time by analyzing business correspondence between the main actors of translation (publisher-translator-author). The translation studies project has become interdisciplinary –it encompasses sociology (concepts of Bourdieu’s ‘Field theory’ are used) and history. The historical research method Histoire croiseé is being used to avoid subjectivity and to introduce a new ‘translator-oriented’ vision in translation studies instead of the author-oriented one. In the course of the archival research, it was established that Jewish background plays an essential role in the destiny of the translators and the publishing house, so the Jewish studies have been added to the project. The study goes beyond the Austrian translational culture; it can be used as an example of dealing with publishing houses policies, publishing translations, and translator studies.Keywords: history of translation, Jewish studies, publishing translations, translation sociology, translator studies, translators as actors
Procedia PDF Downloads 16230991 Structural Performance of Prefabricated Concrete and Reinforced Concrete Structural Walls under Blast Loads
Authors: S. Kamil Akin, Turgut Acikara
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In recent years the world and our country has experienced several explosion events occurred due to terrorist attacks and accidents. In these explosion events many people have lost their lives and many buildings have been damaged. If structures were designed taking the blast loads into account, these results may not have happened or the casualties would have been less. In this thesis analysis of the protection walls have been conducted to prevent the building damage from blast loads. These analyzes was carried out for two different types of wall, concrete and reinforced concrete. Analyses were carried out on four different thicknesses of each wall element. In each wall element the stresses and displacements of the exposed surface due to the detonation charge has been calculated. The limit shear stress and displacement of the wall element according to their material properties has been taken into account. As the result of the analyses the standoff distances and TNT equivalent amount has been determined. According to equivalent TNT amounts and standoff distances the structural response of the protective wall elements has been observed. These structural responses have been observed by ABAQUS finite element package. Explosion loads were brought into effect to the protective wall element models by using the ABAQUS / CONWEP.Keywords: blast loading, blast wave, TNT equivalent method, CONWEP, finite element analysis, detonation
Procedia PDF Downloads 44230990 Evaluation of a Piecewise Linear Mixed-Effects Model in the Analysis of Randomized Cross-over Trial
Authors: Moses Mwangi, Geert Verbeke, Geert Molenberghs
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Cross-over designs are commonly used in randomized clinical trials to estimate efficacy of a new treatment with respect to a reference treatment (placebo or standard). The main advantage of using cross-over design over conventional parallel design is its flexibility, where every subject become its own control, thereby reducing confounding effect. Jones & Kenward, discuss in detail more recent developments in the analysis of cross-over trials. We revisit the simple piecewise linear mixed-effects model, proposed by Mwangi et. al, (in press) for its first application in the analysis of cross-over trials. We compared performance of the proposed piecewise linear mixed-effects model with two commonly cited statistical models namely, (1) Grizzle model; and (2) Jones & Kenward model, used in estimation of the treatment effect, in the analysis of randomized cross-over trial. We estimate two performance measurements (mean square error (MSE) and coverage probability) for the three methods, using data simulated from the proposed piecewise linear mixed-effects model. Piecewise linear mixed-effects model yielded lowest MSE estimates compared to Grizzle and Jones & Kenward models for both small (Nobs=20) and large (Nobs=600) sample sizes. It’s coverage probability were highest compared to Grizzle and Jones & Kenward models for both small and large sample sizes. A piecewise linear mixed-effects model is a better estimator of treatment effect than its two competing estimators (Grizzle and Jones & Kenward models) in the analysis of cross-over trials. The data generating mechanism used in this paper captures two time periods for a simple 2-Treatments x 2-Periods cross-over design. Its application is extendible to more complex cross-over designs with multiple treatments and periods. In addition, it is important to note that, even for single response models, adding more random effects increases the complexity of the model and thus may be difficult or impossible to fit in some cases.Keywords: Evaluation, Grizzle model, Jones & Kenward model, Performance measures, Simulation
Procedia PDF Downloads 12630989 Life in the Time of Lockdown: An Analysis of the Lockdown Imposed during the First Wave of the Novel Corona Virus Pandemic and the Resultant Stress and Anxiety It Caused
Authors: Charu Kriti
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The year 2020 will be remembered in history as the year when everything changed suddenly. As the world is engrossed in fighting a pandemic, individual life has taken a hit. The sudden imposition of lockdown, the perpetual fear of testing positive for the COVID virus, and rescheduling one’s entire life around this one global phenomenon have created unprecedented stress among all cadres. This paper aims to highlight the level of stress that students face during the shift of the classroom from the physical setup to the virtual one. The paper takes into account the day-to-day hassles that a student faces during online classes. The paper also attempts to analyse these from the other perspective of the students’ lives and the difficulties faced by them on all fronts. This is an empirical research paper that takes into account responses from a total of 4,241 students. The responses have been collected via the online survey, which is being assessed and inferred for the purposes of this paper. The final results show the extent of stress that online classes have induced upon the students.Keywords: anxiety, COVID, stress, anxiety disorder
Procedia PDF Downloads 8530988 Challenges in Experimental Testing of a Stiff, Overconsolidated Clay
Authors: Maria Konstadinou, Etienne Alderlieste, Anderson Peccin da Silva, Ben Arntz, Leonard van der Bijl, Wouter Verschueren
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The shear strength and compression properties of stiff Boom clay from Belgium at the depth of about 30 m has been investigated by means of cone penetration and laboratory testing. The latter consisted of index classification, constant rate of strain, direct, simple shear, and unconfined compression tests. The Boom clay samples exhibited strong swelling tendencies. The suction pressure was measured via different procedures and has been compared to the expected in-situ stress. The undrained shear strength and OCR profile determined from CPTs is not compatible with the experimental measurements, which gave significantly lower values. The observed response can be attributed to the presence of pre-existing discontinuities, as shown in microscale CT scans of the samples. The results of this study demonstrate that the microstructure of the clay prior to testing has an impact on the mechanical behaviour and can cause inconsistencies in the comparison of the laboratory test results with in-situ data.Keywords: boom clay, laboratory testing, overconsolidation ratio, stress-strain response, swelling, undrained shear strength
Procedia PDF Downloads 15130987 Primary Resonance in Vortex-Induced Vibration of a Pipeline Close to a Plane Boundary
Authors: Yiming Jin, Ping Dong
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The primary resonance of a pipeline close to a plane boundary is investigated in this paper. Based on classic Van der Pol equation and added a nonlinear item, a new wake oscillator model is proposed to predict the vortex-induced vibration (VIV) of a circular cylinder close to a plane boundary. Then, with the multi-scale method, the approximate solution for the case of the primary resonance is obtained. Besides, to study the characteristic of the primary resonance, the effects of the mass ration, frequency, damp ratio and gap ratio on the frequency-response curves of the pipeline are analysed. On the whole, the trend of the numerical results match up with that of the experimental data well and the mass ration, frequency, damp ratio and gap ratio play an important role in the vortex-induced vibration (VIV) of a circular cylinder close to a plane boundary, especially, the smaller is the mass ratio, the larger impact the gap ratio has on the frequency-response curves of the primary resonance.Keywords: primary resonance, gap ratio, vortex-induced vibration, multi-scale method
Procedia PDF Downloads 37430986 Mathematical Modelling and AI-Based Degradation Analysis of the Second-Life Lithium-Ion Battery Packs for Stationary Applications
Authors: Farhad Salek, Shahaboddin Resalati
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The production of electric vehicles (EVs) featuring lithium-ion battery technology has substantially escalated over the past decade, demonstrating a steady and persistent upward trajectory. The imminent retirement of electric vehicle (EV) batteries after approximately eight years underscores the critical need for their redirection towards recycling, a task complicated by the current inadequacy of recycling infrastructures globally. A potential solution for such concerns involves extending the operational lifespan of electric vehicle (EV) batteries through their utilization in stationary energy storage systems during secondary applications. Such adoptions, however, require addressing the safety concerns associated with batteries’ knee points and thermal runaways. This paper develops an accurate mathematical model representative of the second-life battery packs from a cell-to-pack scale using an equivalent circuit model (ECM) methodology. Neural network algorithms are employed to forecast the degradation parameters based on the EV batteries' aging history to develop a degradation model. The degradation model is integrated with the ECM to reflect the impacts of the cycle aging mechanism on battery parameters during operation. The developed model is tested under real-life load profiles to evaluate the life span of the batteries in various operating conditions. The methodology and the algorithms introduced in this paper can be considered the basis for Battery Management System (BMS) design and techno-economic analysis of such technologies.Keywords: second life battery, electric vehicles, degradation, neural network
Procedia PDF Downloads 7130985 Item-Trait Pattern Recognition of Replenished Items in Multidimensional Computerized Adaptive Testing
Authors: Jianan Sun, Ziwen Ye
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Multidimensional computerized adaptive testing (MCAT) is a popular research topic in psychometrics. It is important for practitioners to clearly know the item-trait patterns of administered items when a test like MCAT is operated. Item-trait pattern recognition refers to detecting which latent traits in a psychological test are measured by each of the specified items. If the item-trait patterns of the replenished items in MCAT item pool are well detected, the interpretability of the items can be improved, which can further promote the abilities of the examinees who attending the MCAT to be accurately estimated. This research explores to solve the item-trait pattern recognition problem of the replenished items in MCAT item pool from the perspective of statistical variable selection. The popular multidimensional item response theory model, multidimensional two-parameter logistic model, is assumed to fit the response data of MCAT. The proposed method uses the least absolute shrinkage and selection operator (LASSO) to detect item-trait patterns of replenished items based on the essential information of item responses and ability estimates of examinees collected from a designed MCAT procedure. Several advantages of the proposed method are outlined. First, the proposed method does not strictly depend on the relative order between the replenished items and the selected operational items, so it allows the replenished items to be mixed into the operational items in reasonable order such as considering content constraints or other test requirements. Second, the LASSO used in this research improves the interpretability of the multidimensional replenished items in MCAT. Third, the proposed method can exert the advantage of shrinkage method idea for variable selection, so it can help to check item quality and key dimension features of replenished items and saves more costs of time and labors in response data collection than traditional factor analysis method. Moreover, the proposed method makes sure the dimensions of replenished items are recognized to be consistent with the dimensions of operational items in MCAT item pool. Simulation studies are conducted to investigate the performance of the proposed method under different conditions for varying dimensionality of item pool, latent trait correlation, item discrimination, test lengths and item selection criteria in MCAT. Results show that the proposed method can accurately detect the item-trait patterns of the replenished items in the two-dimensional and the three-dimensional item pool. Selecting enough operational items from the item pool consisting of high discriminating items by Bayesian A-optimality in MCAT can improve the recognition accuracy of item-trait patterns of replenished items for the proposed method. The pattern recognition accuracy for the conditions with correlated traits is better than those with independent traits especially for the item pool consisting of comparatively low discriminating items. To sum up, the proposed data-driven method based on the LASSO can accurately and efficiently detect the item-trait patterns of replenished items in MCAT.Keywords: item-trait pattern recognition, least absolute shrinkage and selection operator, multidimensional computerized adaptive testing, variable selection
Procedia PDF Downloads 13330984 Case for Simulating Consumer Response to Feed in Tariff Based on Socio-Economic Parameters
Authors: Fahad Javed, Tasneem Akhter, Maria Zafar, Adnan Shafique
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Evaluation and quantification of techniques is critical element of research and development of technology. Simulations and models play an important role in providing the tools for such assessments. When we look at technologies which impact or is dependent on an average Joe consumer then modeling the socio-economic and psychological aspects of the consumer also gain an importance. For feed in tariff for home consumers which is being deployed for average consumer may force many consumers to be adapters of the technology. Understanding how consumers will adapt this technologies thus hold as much significance as evaluating how the techniques would work in consumer agnostic scenarios. In this paper we first build the case for simulators which accommodate socio-economic realities of the consumers to evaluate smart grid technologies, provide a glossary of data that can aid in this effort and present an abstract model to capture and simulate consumers' adaptation and behavioral response to smart grid technologies. We provide a case study to express the power of such simulators.Keywords: smart grids, simulation, socio-economic parameters, feed in tariff (FiT), forecasting
Procedia PDF Downloads 36030983 Communicating Through Symbolisms in Anthropoligical Medicine with Reference to Traditional Performances of Wayang Kulit, Main Puteri and Kuda Kepang
Authors: M. G. Nasuruddin, S. Ishak
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In anthropological medicine (traditional therapeutic healing) symbolic interface are used to connect with the cognitive and metacognitive mechanisms to activate conscious and unconscious response of patients or other recipients. At the same time they are used to communicate with the inhabitants of the nether world to whom are ascribed almost all cases of psychosomatic illness. The symbols, which are cultural specific, are divided into verbal and non-verbal forms of communication. The verbal forms are chanting of mantra and doa and the invocation to invoke the spirits while the non-verbal ones are the physical materials such as the offerings, props and decorative elements, music, movements, olfactory sensation and the performance space. The process of communication through these symbols is affected by the Shaman who is a link or intermediary between the healer (Shaman) and the patients and between the healer and the spirits of the nether world. The paper also examines the scientific perspective of the traditional healing through the use of these symbols. The response to these symbols as external stimuli is embedded in the genes that are linked to the hereditary factor in the person’s DNA. When the patients are tuned in to external stimuli such as music, chanting and singing (sonic orders), it can triggers a response from the brain, which may activate its inner pharmacy by releasing drugs such as dopamine and/or opiodsto ameliorate pain and counter depression, anxiety and create a feel good feeling. These symbols act like placebo, evoking the power of the mind over the body and triggering the innate self-healing energy. At the same time they could also be used as nocebo, for example black magic, which has the opposite effect of placebo. In whatever capacity they operate these symbols, which are either visual or auditory, is an integral part of anthropological medicine. For they communicate and conjure emotional responses that are conducive to healing by activating the internal brain pharmacy.Keywords: communication, healing, placebo, nacebo, symbol
Procedia PDF Downloads 44630982 Defect Induced Enhanced Photoresponse in Graphene
Authors: Prarthana Gowda, Tushar Sakorikar, Siva K. Reddy, Darim B. Ferry, Abha Misra
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Graphene, a two-dimensional carbon allotrope has demonstrated excellent electrical, mechanical and optical properties. A tunable band gap of grapheme demonstrated broad band absorption of light with a response time of picoseconds, however it suffers a fast recombination of the photo generated carriers. Many reports have explored to overcome this problem; in this presentation, we discuss defect induced enhanced photoresponse in a few layer graphene (FLG) due to exposure of infrared (IR) radiation. The two and four-fold enhancement in the photocurrent is achieved by addition of multiwalled carbon nano tubes (MWCNT) to an FLG surface and also creating the wrinkles in the FLG (WG) respectively. In our study, it is also inferred that the photo current generation is highly dependent on the morphological defects on the graphene. It is observed that the FLG (without defects) generates the photo current instantaneously, and after a prolonged exposure to the IR radiation decays the generation rate. Importantly, the presence of MWCNT on FLG enhances the stability and WG presented both stable as well as enhanced photo response.Keywords: graphene, multiwalled carbon nano tubes, wrinkled graphene, photo detector, photo current
Procedia PDF Downloads 41830981 Community Strengths and Indigenous Resilience as Drivers for Health Reform Change
Authors: Shana Malio-Satele, Lemalu Silao Vaisola Sefo
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Introductory Statement: South Seas Healthcare is Ōtara’s largest Pacific health provider in South Auckland, New Zealand. Our vision is excellent health and well-being for Pacific people and all communities through strong Pacific values. During the DELTA and Omicron outbreak of COVID-19, our Pacific people, indigenous Māori, and the community of South Auckland were disproportionately affected and faced significant hardship with existing inequities magnified. This study highlights the community-based learnings of harnessing community-based strengths such as indigenous resilience, family-informed experiences and stories that provide critical insights that inform health reform changes that will be sustainable and equitable for all indigenous populations. This study is based on critical learnings acquired during COVID-19 that challenge the deficit narrative common in healthcare about indigenous populations. This study shares case studies of marginalised groups and religious groups and the successful application of indigenous cultural strengths, such as collectivism, positive protective factors, and using trusted relationships to create meaningful change in the way healthcare is delivered. The significance of this study highlights the critical conditions needed to adopt a community-informed way of creating integrated healthcare that works and the role that the community can play in being part of the solution. Methodologies: Key methodologies utilised are indigenous and Pacific-informed. To achieve critical learnings from the community, Pacific research methodologies, heavily informed by the Polynesian practice, were applied. Specifically, this includes; Teu Le Va (Understanding the importance of trusted relationships as a way of creating positive health solutions); The Fonofale Methodology (A way of understanding how health incorporates culture, family, the physical, spiritual, mental and other dimensions of health, as well as time, context and environment; The Fonua Methodology – Understanding the overall wellbeing and health of communities, families and individuals and their holistic needs and environmental factors and the Talanoa methodology (Researching through conversation, where understanding the individual and community is through understanding their history and future through stories). Major Findings: Key findings in the study included: 1. The collectivist approach in the community is a strengths-based response specific to populations, which highlights the importance of trusted relationships and cultural values to achieve meaningful outcomes. 2. The development of a “village model” which identified critical components to achieving health reform change; system navigation, a sense of service that was culturally responsive, critical leadership roles, culturally appropriate support, and the ability to influence the system enablers to support an alternative way of working. Concluding Statement: There is a strong connection between community-based strengths being implemented into healthcare strategies and reforms and the sustainable success of indigenous populations and marginalised communities accessing services that are cohesive, equitably resourced, accessible and meaningful for families. This study highlights the successful community-informed approaches and practices used during the COVID-19 response in New Zealand that are now being implemented in the current health reform.Keywords: indigenous voice, community voice, health reform, New Zealand
Procedia PDF Downloads 9530980 Mesenteric Vasculitis Causing Perforated Diverticulitis Mimicking Abdominal Sepsis
Authors: Christopher Leung, Assad Zahid
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Mesenteric vasculitis can often mimic abdominal sepsis in a postoperative setting leading to a predicament where steroids could improve mesenteric vasculitis whilst worsening abdominal sepsis. Here this study presents a unique and rare case of perforated sigmoid diverticulitis secondary to systemic vasculitis. A 68-year-old gentleman presented with perforated sigmoid diverticulitis requiring an emergency Hartmann’s procedure. Early in his postoperative course, he had painful and asymmetrical neuropathy that, after a careful history and examination, revealed a patient with mono neuritis multiplex on a background history of longstanding rheumatoid arthritis. On day seven of his postoperative course, he had rising inflammatory markers and a CT abdomen and pelvis showing fluid around the mesentery. Whilst contamination from sigmoid perforation was somewhat congruent with these signs, a diagnosis of polyarteritis nodosa, a common cause of mononeuritis multiplex, is also possible, although involvement of the large bowel in polyarteritis nodosa is extremely rare. The histopathology from the initial Hartmann’s procedure was re-examined, showing medium vessel disease vasculitis. Given his lack of fevers, absence of abdominal pain, and worsening neurology, he was given a provisional diagnosis of polyarteritis nodosa and was treated successfully, not on IV antibiotics but on steroids. Large bowel involvement of polyarteritis nodosa is extremely rare and this is the first case of polyarteritis nodosa causing perforated diverticulitis. The learning point here is to obtain a good clinical picture of a patient to identify mesenteric vasculitis as compared to abdominal sepsis as the treatment of one worsens the other.Keywords: abdominal sepsis, diverticulitis, mesenteric vasculitis, polyarteritis nodosa
Procedia PDF Downloads 25730979 The Problem of Suffering: Job, The Servant and Prophet of God
Authors: Barbara Pemberton
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Now that people of all faiths are experiencing suffering due to many global issues, shared narratives may provide common ground in which true understanding of each other may take root. This paper will consider the all too common problem of suffering and address how adherents of the three great monotheistic religions seek understanding and the appropriate believer’s response from the same story found within their respective sacred texts. Most scholars from each of these three traditions—Judaism, Christianity, and Islam— consider the writings of the Tanakh/Old Testament to at least contain divine revelation. While they may not agree on the extent of the revelation or the method of its delivery, they do share stories as well as a common desire to glean God’s message for God’s people from the pages of the text. One such shared story is that of Job, the servant of Yahweh--called Ayyub, the prophet of Allah, in the Qur’an. Job is described as a pious, righteous man who loses everything—family, possessions, and health—when his faith is tested. Three friends come to console him. Through it, all Job remains faithful to his God who rewards him by restoring all that was lost. All three hermeneutic communities consider Job to be an archetype of human response to suffering, regarding Job’s response to his situation as exemplary. The story of Job addresses more than the distribution of the evil problem. At stake in the story is Job’s very relationship to his God. Some exegetes believe that Job was adapted into the Jewish milieu by a gifted redactor who used the original ancient tale as the “frame” for the biblical account (chapters 1, 2, and 4:7-17) and then enlarged the story with the complex center section of poetic dialogues creating a complex work with numerous possible interpretations. Within the poetic center, Job goes so far as to question God, a response to which Jews relate, finding strength in dialogue—even in wrestling with God. Muslims only embrace the Job of the biblical narrative frame, as further identified through the Qur’an and the prophetic traditions, considering the center section an errant human addition not representative of a true prophet of Islam. The Qur’anic injunction against questioning God also renders the center theologically suspect. Christians also draw various responses from the story of Job. While many believers may agree with the Islamic perspective of God’s ultimate sovereignty, others would join their Jewish neighbors in questioning God, not anticipating answers but rather an awareness of his presence—peace and hope becoming a reality experienced through the indwelling presence of God’s Holy Spirit. Related questions are as endless as the possible responses. This paper will consider a few of the many Jewish, Christian, and Islamic insights from the ancient story, in hopes adherents within each tradition will use it to better understand the other faiths’ approach to suffering.Keywords: suffering, Job, Qur'an, tanakh
Procedia PDF Downloads 19030978 Photocatalytic Degradation of Produced Water Hydrocarbon of an Oil Field by Using Ag-Doped TiO₂ Nanoparticles
Authors: Hamed Bazrafshan, Saeideh Dabirnia, Zahra Alipour Tesieh, Samaneh Alavi, Bahram Dabir
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In this study, the removal of pollutants of a real produced water sample from an oil reservoir (a light oil reservoir), using a photocatalytic degradation process in a cylindrical glass reactor, was investigated. Using TiO₂ and Ag-TiO₂ in slurry form, the photocatalytic degradation was studied by measuring the COD parameter, qualitative analysis, and GC-MS. At first, optimization of the parameters on photocatalytic degradation of hydrocarbon pollutants in real produced water, using TiO₂ nanoparticles as photocatalysts under UV light, was carried out applying response surface methodology. The results of the design of the experiment showed that the optimum conditions were at a catalyst concentration of 1.14 g/lit and pH of 2.67, and the percentage of COD removal was 72.65%.Keywords: photocatalyst, Ag-doped, TiO₂, produced water, nanoparticles
Procedia PDF Downloads 13530977 Optimization of Moisture Content for Highest Tensile Strength of Instant Soluble Milk Tablet and Flowability of Milk Powder
Authors: Siddharth Vishwakarma, Danie Shajie A., Mishra H. N.
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Milk powder becomes very useful in the low milk supply area but the exact amount to add for one glass of milk and the handling is difficult. So, the idea of instant soluble milk tablet comes into existence for its high solubility and easy handling. The moisture content of milk tablets is increased by the direct addition of water with no additives for binding. The variation of the tensile strength of instant soluble milk tablets and the flowability of milk powder with the moisture content is analyzed and optimized for the highest tensile strength of instant soluble milk tablets and flowability, above a particular value of milk powder using response surface methodology. The flowability value is necessary for ease in quantifying the milk powder, as a feed, in the designed tablet making machine. The instant soluble nature of milk tablets purely depends upon the disintegration characteristic of tablets in water whose study is under progress. Conclusions: The optimization results are very useful in the commercialization of milk tablets.Keywords: flowability, milk powder, response surface methodology, tablet making machine, tensile strength
Procedia PDF Downloads 185