Search results for: features comparison
2999 Association of Human Immunodeficiency Virus with Incident Autoimmune Hemolytic Anemia: A Population-Based Cohort Study in Taiwan
Authors: Yung-Feng Yen, I-an Jen, Yi-Ming Arthur Chen
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The molecular mimicry between human immunodeficiency virus (HIV) protein and red blood cell (RBC) antigens could induce the production of anti-RBC autoantibodies. However, the association between HIV infection and subsequent development of autoimmune hemolytic anemia (AIHA) remains unclear. This nationwide population-based cohort study aimed to determine the association between incident AIHA and HIV in Taiwan. From 2000–2012, we identified adult people living with HIV/AIDS (PLWHA) from the Taiwan centers for disease control HIV Surveillance System. HIV-infected individuals were defined by positive HIV-1 western blot. Age- and sex-matched controls without HIV infection were selected from the Taiwan National Health Insurance Research Database for comparison. All patients were followed until Dec. 31, 2012, and observed for occurrence of AIHA. Of 171,468 subjects (19,052 PLWHA, 152,416 controls), 30 (0.02%) had incident AIHA during a mean follow-up of 5.45 years, including 23 (0.12%) PLWHA and 7 (0.01%) controls. After adjusting for potential confounders, HIV infection was found to be an independent risk factor of incident AIHA (adjusted hazard ratio [AHR], 20.9; 95% confidence interval [CI], 8.34-52.3). Moreover, PLWHA receiving HAART were more likely to develop AIHA than those not receiving HAART (AHR, 10.8; 95% CI, 2.90-40.1). Additionally, the risk of AIHA was significantly increased in those taking efavirenz (AHR, 3.15; 95% CI, 1.18-8.43) or atazanavir (AHR, 6.58; 95% CI, 1.88-22.9) component of the HAART. In conclusion, HIV infection is an independent risk factor for incident AIHA. Clinicians need to be aware of the higher risk of AIHA in PLWHA.Keywords: autoimmune disease , hemolytic anemia, HIV, highly active antiretroviral treatment
Procedia PDF Downloads 2362998 Assessing Effectiveness of Schema Mode Therapy and Emotionally Focused Couples Therapy in Attachment Styles among Couples with Marital Conflict
Authors: Reza Johari Fard, Najmeh Cheraghi, Parvin Ehtesham Zadeh, Parviz Asgari
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The aim of this study was to investigate and comparison of the effectiveness of schema mode therapy and emotionally focused couples therapy in attachment styles (secure, avoidant, and anxious) in couples with marital conflict in a quasiexperimental method in a pretest, posttest, and follow up design with a control group. The statistical population of the study included all the couples with marital conflict who visited the Mehrana counseling center in 2019 in Ahvaz, Iran 45 couples were selected by voluntary sampling method and randomly divided into two experimental groups and one control group (15 pairs in each group). The participants completed the Adult Attachment Scale (Hazan and Shaver). The experimental groups underwent schema mode therapy and emotionally focused couples therapy for 12 sessions, but the control group did not receive any intervention. The data were analyzed by the statistical analysis of repeated measures in SPSS-19 software. The results showed that both schema mode therapy and emotionally focused couples therapy are effective in increasing the secure attachment style and reducing avoidant and ambivalent attachment styles in couples with marital conflict. There was no significant difference between the schema mode therapy group and the emotionally focused couple's therapy group in attachment styles. Therefore, it is recommended that therapists and family counselors use these therapies along with other therapeutic interventions to increase secure attachment styles and reduce marital conflicts.Keywords: schema mode therapy, emotional focused couple therapy, attachment styles, marital conflict
Procedia PDF Downloads 1172997 The Construct of Personal Choice within Individual Language Shift: A Phenomenological Qualitative Study
Authors: Kira Gulko Morse
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Choosing one’s primary language may not be as common as choosing an additional foreign language to study or use during travel. In some instances, however, it becomes a matter of internal personal struggle, as language is tied not only to specific circumstances but also to human background and identity. This phenomenological qualitative study focuses on the factors affecting the decision of a person to undergo a language shift. Specifically, it considers how these factors relate to identity negotiation and expression. The data for the study include the analysis of published autobiographical narratives and personal interviews conducted using the Responsive Interviewing model. While research participants come from a variety of geographical locations and have used different reasons for undergoing their individual language shift, the study identifies a number of common features shared by all the participants. Specifically, while all the participants have been able to maintain their first language to varying degrees of proficiency, they have all completed the shift to establish a primary language different from their first. Additionally, the process of self-identification is found to be directly connected to the phenomenon of language choice for each of the participants. The findings of the study further tie the phenomenon of individual language shift to a more comprehensive issue of individual life choices – ethnic revival, immigration, and inter-cultural marriage among others. The study discusses varying language roles and the data indicate that language shift may occur whether it is a symbolic driving force or a secondary means in fulfilling a set life goal. The concept of language addition is suggested as an alternative to the arbitrariness of language shift. Thus, instead of focusing on subtractive bilingualism or language loss, the emphasis becomes the integration of languages within the individual. The study emphasizes the importance of the construct of personal choice in its connection to individual language shift. It places the focus from society onto an individual and the ability of an individual to make decisions in matters of linguistic identification.Keywords: choice theory, identity negotiation, language shift, psycholinguistics
Procedia PDF Downloads 1382996 True and False Cognates of Japanese, Chinese and Philippine Languages: A Contrastive Analysis
Authors: Jose Marie E. Ocdenaria, Riceli C. Mendoza
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Culturally, languages meet, merge, share, exchange, appropriate, donate, and divide in and to and from each other. Further, this type of recurrence manifests in East Asian cultures, where language influence diffuses across geographical proximities. Historically, China has notable impacts on Japan’s culture. For instance, Japanese borrowed words from China and their way of reading and writing. This qualitative and descriptive employing contrastive analysis study addressed the true and false cognates of Japanese-Philippine languages and Chinese-Philippine languages. It involved a rich collection of data from various sources like textual pieces of evidence or corpora to gain a deeper understanding of true and false cognates between L1 and L2. Cognates of Japanese-Philippine languages and Chinese-Philippine languages were analyzed contrastively according to orthography, phonology, and semantics. The words presented were the roots; however, derivatives, reduplications, and variants of stress were included when they shed emphases on the comparison. The basis of grouping the cognates was its phonetic-semantic resemblance. Based on the analysis, it revealed that there are words which may have several types of lexical relationship. Further, the study revealed that the Japanese language has more false cognates in the Philippine languages, particularly in Tagalog and Cebuano. On the other hand, there are more true cognates of Chinese in Tagalog. It is the hope of this study to provide a significant contribution to a diverse audience. These include the teachers and learners of foreign languages such as Japanese and Chinese, future researchers and investigators, applied linguists, curricular theorists, community, and publishers.Keywords: Contrastive Analysis, Japanese, Chinese and Philippine languages, Qualitative and descriptive study, True and False Cognates
Procedia PDF Downloads 1412995 Prediction of Pounding between Two SDOF Systems by Using Link Element Based On Mathematic Relations and Suggestion of New Equation for Impact Damping Ratio
Authors: Seyed M. Khatami, H. Naderpour, R. Vahdani, R. C. Barros
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Many previous studies have been carried out to calculate the impact force and the dissipated energy between two neighboring buildings during seismic excitation, when they collide with each other. Numerical studies are an important part of impact, which several researchers have tried to simulate the impact by using different formulas. Estimation of the impact force and the dissipated energy depends significantly on some parameters of impact. Mass of bodies, stiffness of spring, coefficient of restitution, damping ratio of dashpot and impact velocity are some known and unknown parameters to simulate the impact and measure dissipated energy during collision. Collision is usually shown by force-displacement hysteresis curve. The enclosed area of the hysteresis loop explains the dissipated energy during impact. In this paper, the effect of using different types of impact models is investigated in order to calculate the impact force. To increase the accuracy of impact model and to optimize the results of simulations, a new damping equation is assumed and is validated to get the best results of impact force and dissipated energy, which can show the accuracy of suggested equation of motion in comparison with other formulas. This relation is called "n-m". Based on mathematical relation, an initial value is selected for the mentioned coefficients and kinetic energy loss is calculated. After each simulation, kinetic energy loss and energy dissipation are compared with each other. If they are equal, selected parameters are true and, if not, the constant of parameters are modified and a new analysis is performed. Finally, two unknown parameters are suggested to estimate the impact force and calculate the dissipated energy.Keywords: impact force, dissipated energy, kinetic energy loss, damping relation
Procedia PDF Downloads 5552994 Numerical Study on Response of Polymer Electrolyte Fuel Cell (PEFCs) with Defects under Different Load Conditions
Authors: Muhammad Faizan Chinannai, Jaeseung Lee, Mohamed Hassan Gundu, Hyunchul Ju
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Fuel cell is known to be an effective renewable energy resource which is commercializing in the present era. It is really important to know about the improvement in performance even when the system faces some defects. This study was carried out to analyze the performance of the Polymer electrolyte fuel cell (PEFCs) under different operating conditions such as current density, relative humidity and Pt loadings considering defects with load changes. The purpose of this study is to analyze the response of the fuel cell system with defects in Balance of Plants (BOPs) and catalyst layer (CL) degradation by maintaining the coolant flow rate as such to preserve the cell temperature at the required level. Multi-Scale Simulation of 3D two-phase PEFC model with coolant was carried out under different load conditions. For detailed analysis and performance comparison, extensive contours of temperature, current density, water content, and relative humidity are provided. The simulation results of the different cases are compared with the reference data. Hence the response of the fuel cell stack with defects in BOP and CL degradations can be analyzed by the temperature difference between the coolant outlet and membrane electrode assembly. The results showed that the Failure of the humidifier increases High-Frequency Resistance (HFR), air flow defects and CL degradation results in the non-uniformity of current density distribution and high cathode activation overpotential, respectively.Keywords: PEM fuel cell, fuel cell modeling, performance analysis, BOP components, current density distribution, degradation
Procedia PDF Downloads 2162993 The Rehabilitation of Drug Addiction by Thai Indigenous Knowledge: A Case Study of Thamkrabok Monastery
Authors: Wanwimon Mekwimon
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Drug addiction is a serious problem in Thailand which has occurred continuously and repeatedly and enormously impacting health and economy of drug users. The indigenous wisdom and folk medicine is an attractive alternative choice, especially in detoxification and rehabilitation period. There are two objectives: First is to study about rehabilitation process and the curing for drug eaters and 2nd is to investigate the effectiveness of the curing and rehabilitation process by indigenous wisdom at Tamkrabok monastery, Pra-Puttabat district, Saraburi province. The main informants are 10 curers, 15 patients and 17 after-1-year rehabilitators. In the process, the semi-structured questionnaire is administered, the data are analyzed and proved by triangulation. The curing and rehabilitation process which use herbal remedies has a period of 15 days (5 days for detoxification and 10 days for recovery period) and the occupational training and self-consciousness awakening were delivered. The follow-up process includes twice-a-month recall for 6 months, follow-up letters and in depth interview with their families. The outcome of 1 year post-treatment was 94% (16 from 17). There are many reasons for not relapsing: the recovering patients have drawn on their inner strength, self-awareness and coping skill as well as their family and social support while rehabilitation process which includes difficulties in contacting with family members. They can void themselves from high risk situations to relapse. Recommendations: The follow-up system should be improved for continuous quality improvement, there should be the qualification standard for herbal remedies and the comparison among rehabilitation process of Tamkrabok and another methods are to be guideline for the further development.Keywords: rehabilitation, drug addiction, Thai indigenous knowledge, herbal remedies
Procedia PDF Downloads 2462992 Misdiagnosed Mammary Analogue Secretory Carcinoma of the Salivary Gland: A Case Report with a Review of the Literature
Authors: Yaya Gao, Jifeng Liu, Yafeng Liu
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Objectives: This study aimed to improve clinicians' understanding and diagnosis of the Mammary analogue secretory carcinoma of the salivary gland(MASC). Methods: The clinical features of a MASC patient who was admitted to WestChina Hospital of Sichuan University in July 2020 were reviewed and analyzed. A 49-year-old woman with left upper neck pain for three months was admitted to the hospital. She underwent adenoma resection of the left submandibular gland 14 years ago and mucoepidermoid carcinoma resection surgery five years ago. Three months before admission, the patient developed pain in the left mandibular angle after "fatigue" and gradually developed radiation pain in the left ear, which could be relieved after rest. A mass of 1cm could be touched at the mandibular, with tenderness, poor mobility, and hard texture. No swelling, heat, pain, rupture, or pus was found on the surrounding skin. Color doppler ultrasonography of the salivary gland indicated a weak echo mass of 23*14*17mm in the left parotid gland. Results: Surgical excision was completed. Immunohistochemistry of the tumor samples after operation showed that P63(a few,+), CK7(+), S100(+), DOG1(-), Ki67(MIB-1)(+,5%),pan-TRK(+), PAS(+) . ETV-6 gene translocation was detected in FISH in postoperative pathology, which indicated MASC. After this diagnosis, the patient sent the postoperative specimen of the second submandibular tumor to our hospital for consultation. The morphology of the two was similar. FISH detected ETV-6 gene translocation, so the second pathological diagnosis was revised to MASC. Conclusion: MASC of the salivary gland is a rare salivary gland tumor whose diagnosis depends on the result of the ETV6-NTRK3 fusion gene.Keywords: mammary analogue secretory carcinoma, ETV6-NTRK3, salivary gland, misdiagnosed
Procedia PDF Downloads 652991 Examining the Relationship between Concussion and Neurodegenerative Disorders: A Review on Amyotrophic Lateral Sclerosis and Alzheimer’s Disease
Authors: Edward Poluyi, Eghosa Morgan, Charles Poluyi, Chibuikem Ikwuegbuenyi, Grace Imaguezegie
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Background: Current epidemiological studies have examined the associations between moderate and severe traumatic brain injury (TBI) and their risks of developing neurodegenerative diseases. Concussion, also known as mild TBI (mTBI), is however quite distinct from moderate or severe TBIs. Only few studies in this burgeoning area have examined concussion—especially repetitive episodes—and neurodegenerative diseases. Thus, no definite relationship has been established between them. Objectives : This review will discuss the available literature linking concussion and amyotrophic lateral sclerosis (ALS) and Alzheimer’s disease (AD). Materials and Methods: Given the complexity of this subject, a realistic review methodology was selected which includes clarifying the scope and developing a theoretical framework, developing a search strategy, selection and appraisal, data extraction, and synthesis. A detailed literature matrix was set out in order to get relevant and recent findings on this topic. Results: Presently, there is no objective clinical test for the diagnosis of concussion because the features are less obvious on physical examination. Absence of an objective test in diagnosing concussion sometimes leads to skepticism when confirming the presence or absence of concussion. Intriguingly, several possible explanations have been proposed in the pathological mechanisms that lead to the development of some neurodegenerative disorders (such as ALS and AD) and concussion but the two major events are deposition of tau proteins (abnormal microtubule proteins) and neuroinflammation, which ranges from glutamate excitotoxicity pathways and inflammatory pathways (which leads to a rise in the metabolic demands of microglia cells and neurons), to mitochondrial function via the oxidative pathways.Keywords: amyotrophic lateral sclerosis, Alzheimer's disease, mild traumatic brain injury, neurodegeneration
Procedia PDF Downloads 932990 Feasibilities for Recovering of Precious Metals from Printed Circuit Board Waste
Authors: Simona Ziukaite, Remigijus Ivanauskas, Gintaras Denafas
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Market development of electrical and electronic equipment and a short life cycle is driven by the increasing waste streams. Gold Au, copper Cu, silver Ag and palladium Pd can be found on printed circuit board. These metals make up the largest value of printed circuit board. Therefore, the printed circuit boards scrap is valuable as potential raw material for precious metals recovery. A comparison of Cu, Au, Ag, Pd recovery from waste printed circuit techniques was selected metals leaching of chemical reagents. The study was conducted using the selected multistage technique for Au, Cu, Ag, Pd recovery of printed circuit board. In the first and second metals leaching stages, as the elution reagent, 2M H2SO4 and H2O2 (35%) was used. In the third stage, leaching of precious metals used solution of 20 g/l of thiourea and 6 g/l of Fe2 (SO4)3. Verify the efficiency of the method was carried out the metals leaching test with aqua regia. Based on the experimental study, the leaching efficiency, using the preferred methodology, 60 % of Au and 85,5 % of Cu dissolution was achieved. Metals leaching efficiency after waste mechanical crushing and thermal treatment have been increased by 1,7 times (40 %) for copper, 1,6 times (37 %) for gold and 1,8 times (44 %) for silver. It was noticed that, the Au amount in old (> 20 years) waste is 17 times more, Cu amount - 4 times more, and Ag - 2 times more than in the new (< 1 years) waste. Palladium in the new printed circuit board waste has not been found, however, it was established that from 1 t of old printed circuit board waste can be recovered 1,064 g of Pd (leaching with aqua regia). It was found that from 1 t of old printed circuit board waste can be recovered 1,064 g of Ag. Precious metals recovery in Lithuania was estimated in this study. Given the amounts of generated printed circuit board waste, the limits for recovery of precious metals were identified.Keywords: leaching efficiency, limits for recovery, precious metals recovery, printed circuit board waste
Procedia PDF Downloads 4002989 The DAQ Debugger for iFDAQ of the COMPASS Experiment
Authors: Y. Bai, M. Bodlak, V. Frolov, S. Huber, V. Jary, I. Konorov, D. Levit, J. Novy, D. Steffen, O. Subrt, M. Virius
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In general, state-of-the-art Data Acquisition Systems (DAQ) in high energy physics experiments must satisfy high requirements in terms of reliability, efficiency and data rate capability. This paper presents the development and deployment of a debugging tool named DAQ Debugger for the intelligent, FPGA-based Data Acquisition System (iFDAQ) of the COMPASS experiment at CERN. Utilizing a hardware event builder, the iFDAQ is designed to be able to readout data at the average maximum rate of 1.5 GB/s of the experiment. In complex softwares, such as the iFDAQ, having thousands of lines of code, the debugging process is absolutely essential to reveal all software issues. Unfortunately, conventional debugging of the iFDAQ is not possible during the real data taking. The DAQ Debugger is a tool for identifying a problem, isolating the source of the problem, and then either correcting the problem or determining a way to work around it. It provides the layer for an easy integration to any process and has no impact on the process performance. Based on handling of system signals, the DAQ Debugger represents an alternative to conventional debuggers provided by most integrated development environments. Whenever problem occurs, it generates reports containing all necessary information important for a deeper investigation and analysis. The DAQ Debugger was fully incorporated to all processes in the iFDAQ during the run 2016. It helped to reveal remaining software issues and improved significantly the stability of the system in comparison with the previous run. In the paper, we present the DAQ Debugger from several insights and discuss it in a detailed way.Keywords: DAQ Debugger, data acquisition system, FPGA, system signals, Qt framework
Procedia PDF Downloads 2862988 Modeling of Strong Motion Generation Areas of the 2011 Tohoku, Japan Earthquake Using Modified Semi-Empirical Technique Incorporating Frequency Dependent Radiation Pattern Model
Authors: Sandeep, A. Joshi, Kamal, Piu Dhibar, Parveen Kumar
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In the present work strong ground motion has been simulated using a modified semi-empirical technique (MSET), with frequency dependent radiation pattern model. Joshi et al. (2014) have modified the semi-empirical technique to incorporate the modeling of strong motion generation areas (SMGAs). A frequency dependent radiation pattern model is applied to simulate high frequency ground motion more precisely. Identified SMGAs (Kurahashi and Irikura 2012) of the 2011 Tohoku earthquake (Mw 9.0) were modeled using this modified technique. Records are simulated for both frequency dependent and constant radiation pattern function. Simulated records for both cases are compared with observed records in terms of peak ground acceleration and pseudo acceleration response spectra at different stations. Comparison of simulated and observed records in terms of root mean square error suggests that the method is capable of simulating record which matches in a wide frequency range for this earthquake and bears realistic appearance in terms of shape and strong motion parameters. The results confirm the efficacy and suitability of rupture model defined by five SMGAs for the developed modified technique.Keywords: strong ground motion, semi-empirical, strong motion generation area, frequency dependent radiation pattern, 2011 Tohoku Earthquake
Procedia PDF Downloads 5422987 Exploring the Role of Phosphorylation on the β-lactamase Activity of OXA24/40
Authors: Dharshika Rajalingam, Jeffery W. Peng
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Acinetobacter baumannii is a challenging threat to global health, recognized as a multidrug-resistant pathogen. -lactamase is one of the principal resistant mechanisms developed by A. baumannii to survive against -lactam antibiotics. OXA24/40 is one of the types of -lactamases, a well-documented carbapenem hydrolyzing class D -lactamases (CHDL). It was revealed that OXA24/40 showed resistivity against doripenem, one of the carbapenems, by two different mechanisms as hydrolysis and -lactonization. Furthermore, it undergoes genetic mutations to broaden the -lactamase activity to survive against antibiotic environments. One of the crucial characterizations of prokaryotes to develop adaptation is post-translational modification (PTM), mainly phosphorylation. However, the PTM of OXA24/40 is an unknown feature, and the impact of PTM on antibiotic resistivity is yet to be explored. We approached these hypotheses using NMR and MS techniques and found that the OXA24/40 could be phosphorylated in vitro. The Ser81 at the active STFK motif of OXA24/40 of catalytic pocket was identified as the site of phosphorylation using 1D 31P NMR experiment, whereas S81 is required to form an acyl-enzyme complex between enzyme and -lactam antibiotics. The activity of completely phosphorylated OXA24/40 wild type against doripenem revealed that the phosphorylation of active Ser inactivates the -lactamases activity of OXA24/40. The 1D 1H CPMG NMR-based activity assay of phosphorylated OXA24/40 against doripenem confirmed that both deactivating mechanisms are inhibited by phosphorylation. Carbamylated Lysine at the active STFK motif is one of the critical features of CHDL required for the acylation and deacylation reactions of the enzyme. The 1D 13C NMR experiment confirmed that the K84 of phosphorylated OXA24/40 is de-carbamylated. Phosphorylation of OXA24/40 affects both active S81 and carbamylated K84 of OXA24 that are required for the resistivity of -lactamase. So, phosphorylation could be one of the reasons for the genetic mutation of OXA24/40 for the development of antibiotic resistivity. Further research can lead to an understanding of the effect of phosphorylation on the clinical mutants of the OXA24-like -lactamase family on the broadening of -lactamase activity.Keywords: OXA24/40, phosphorylation, clinical mutants, resistivity
Procedia PDF Downloads 832986 Confessional Features of Pilgrimage in Ukraine and Germany: Cultural Experience
Authors: Svitlana Panchenko
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Tourism in Ukraine is an underdeveloped branch of the economy, religious tourism is in its infancy. New challenges of the time, the Covid-19 pandemic and the war are making adjustments, and religious tourism is now in a difficult situation. Although, as scientists describe, it was religious tourism during the pandemic that proved to be a sustainable form of tourism, surviving due to the stability of faith of believers. Tourism in Germany is quite developed and profitable industry, so its interesting for studing such places of pilgrimage in Bavaria as: Passau, Regensburg, Munich, these cities are rich in their shrines and sacred places. In Germany, religious tourism is a well-developed economic sector, so it is necessary to study this issue from the point of view of attracting foreign tourists to Ukrainian lands to visit the shrines. For example, the city of Trier received a large part of the relics of Saint Matthew the Apostle, the relics of the Saint have remained a place of world Christian pilgrimage for centuries. This is the only city in Germany where there are relics of the apostle. Basically, all the relics of the holy apostles are kept in Italy, some in Spain and France. It is important to study different confessional groups, their psychology, the purpose of the pilgrimage, description of shrines. The subject of the study is religious tourism in the cities and villages of Transcarpathia and Bavaria, taking into account the psychological characteristics of pilgrims from a multi-confessional point of view. The article used the culturological, phenomenological, religious studies methods, which allows to analyze the problems of religious tourism from this point of view, taking into account the specifics of this sphere. The results of the research consist in the study of multi-confessional shrines on the example of Ukrainian and German towns to study the importance of cultural heritage and pilgrimage routes, taking into account the psychological factors of pilgrims.Keywords: communications, cultural heritage, pilgrimage, religious tourism
Procedia PDF Downloads 922985 Social Media Factor in Security Environment
Authors: Cetin Arslan, Senol Tayan
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Social media is one of the most important and effective means of social interaction among people in which they create, share and exchange their ideas via photos, videos or voice messages. Although there are lots of communication tools, social media sites are the most prominent ones that allows the users articulate themselves in a matter of seconds all around the world with almost any expenses and thus, they became very popular and widespread after its emergence. As the usage of social media increases, it becomes an effective instrument in social matters. While it is possible to use social media to emphasize basic human rights and protest some failures of any government as in “Arab Spring”, it is also possible to spread propaganda and misinformation just to cause long lasting insurgency, upheaval, turmoil or disorder as an instrument of intervention to internal affairs and state sovereignty by some hostile groups or countries. It is certain that “social media” has positive effects on democracies letting people have chance to express themselves and to organize, but it is also obvious that the misuse of it, is very common that even a five-minute-long video can cause to wage a campaign against a country. Although it looks anti-democratic, when you consider the catastrophic effects of misuse of social media, it is a kind of area that serious precautions are to be taken without limiting democratic rights while allowing constant and perpetual share but preventing the criminal events. This article begins with the current developments in social media and gives some examples on misuse of it. Second part tries to put emphasize on the legal basis that can prevent criminal activities and the upheavals and insurgencies against state security. Last part makes comparison between democratic countries and international organizations’’ actions against such activities and proposes some further actions that are compatible with democratic norms.Keywords: democracy, disorder, security, Social Media
Procedia PDF Downloads 3682984 Viscoelastic Properties of Sn-15%Pb Measured in an Oscillation Test
Authors: Gerardo Sanjuan Sanjuan, Ángel Enrique Chavéz Castellanos
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The knowledge of the rheological behavior of partially solidified metal alloy is an important issue when modeling and simulation of die filling in semisolid processes. Many experiments for like steady state, the step change in shear rate tests, shear stress ramps have been carried out leading that semi-solid alloys exhibit shear thinning, thixotropic behavior and yield stress. More advanced investigation gives evidence some viscoelastic features can be observed. The viscoelastic properties of materials are determinate by transient or dynamic methods; unfortunately, sparse information exists about oscillation experiments. The aim of this present work is to use small amplitude oscillatory tests for knowledge properties such as G´ and G´´. These properties allow providing information about materials structure. For this purpose, we investigated tin-lead alloy (Sn-15%Pb) which exhibits a similar microstructure to aluminum alloys and is the classic alloy for semisolid thixotropic studies. The experiments were performed with parallel plates rheometer AR-G2. Initially, the liquid alloy is cooled down to the semisolid range, a specific temperature to guarantee a constant fraction solid. Oscillation was performed within the linear viscoelastic regime with a strain sweep. So, the loss modulus G´´, the storage modulus G´ and the loss angle (δ) was monitored. In addition a frequency sweep at a strain below the critical strain for characterized its structure. This provides more information about the interactions among solid particles on a liquid matrix. After testing, the sample was removed then cooled, sectioned and examined metallographically. These experiments demonstrate that the viscoelasticity is sensitive to the solid fraction, and is strongly influenced by the shape and size of particles solid.Keywords: rheology, semisolid alloys, thixotropic, viscoelasticity
Procedia PDF Downloads 3832983 Numerical Simulation of the Dynamic Behavior of a LaNi5 Water Pumping System
Authors: Miled Amel, Ben Maad Hatem, Askri Faouzi, Ben Nasrallah Sassi
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Metal hydride water pumping system uses hydrogen as working fluid to pump water for low head and high discharge. The principal operation of this pump is based on the desorption of hydrogen at high pressure and its absorption at low pressure by a metal hydride. This work is devoted to study a concept of the dynamic behavior of a metal hydride pump using unsteady model and LaNi5 as hydriding alloy. This study shows that with MHP, it is possible to pump 340l/kg-cycle of water in 15 000s using 1 Kg of LaNi5 at a desorption temperature of 360 K, a pumping head equal to 5 m and a desorption gear ratio equal to 33. This study reveals also that the error given by the steady model, using LaNi5 is about 2%.A dimensional mathematical model and the governing equations of the pump were presented to predict the coupled heat and mass transfer within the MHP. Then, a numerical simulation is carried out to present the time evolution of the specific water discharge and to test the effect of different parameters (desorption temperature, absorption temperature, desorption gear ratio) on the performance of the water pumping system (specific water discharge, pumping efficiency and pumping time). In addition, a comparison between results obtained with steady and unsteady model is performed with different hydride mass. Finally, a geometric configuration of the reactor is simulated to optimize the pumping time.Keywords: dynamic behavior, LaNi5, performance of water pumping system, unsteady model
Procedia PDF Downloads 2082982 Pneumoperitoneum Creation Assisted with Optical Coherence Tomography and Automatic Identification
Authors: Eric Yi-Hsiu Huang, Meng-Chun Kao, Wen-Chuan Kuo
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For every laparoscopic surgery, a safe pneumoperitoneumcreation (gaining access to the peritoneal cavity) is the first and essential step. However, closed pneumoperitoneum is usually obtained by blind insertion of a Veress needle into the peritoneal cavity, which may carry potential risks suchas bowel and vascular injury.Until now, there remains no definite measure to visually confirm the position of the needle tip inside the peritoneal cavity. Therefore, this study established an image-guided Veress needle method by combining a fiber probe with optical coherence tomography (OCT). An algorithm was also proposed for determining the exact location of the needle tip through the acquisition of OCT images. Our method not only generates a series of “live” two-dimensional (2D) images during the needle puncture toward the peritoneal cavity but also can eliminate operator variation in image judgment, thus improving peritoneal access safety. This study was approved by the Ethics Committee of Taipei Veterans General Hospital (Taipei VGH IACUC 2020-144). A total of 2400 in vivo OCT images, independent of each other, were acquired from experiments of forty peritoneal punctures on two piglets. Characteristic OCT image patterns could be observed during the puncturing process. The ROC curve demonstrates the discrimination capability of these quantitative image features of the classifier, showing the accuracy of the classifier for determining the inside vs. outside of the peritoneal was 98% (AUC=0.98). In summary, the present study demonstrates the ability of the combination of our proposed automatic identification method and OCT imaging for automatically and objectively identifying the location of the needle tip. OCT images translate the blind closed technique of peritoneal access into a visualized procedure, thus improving peritoneal access safety.Keywords: pneumoperitoneum, optical coherence tomography, automatic identification, veress needle
Procedia PDF Downloads 1362981 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 2892980 Adaptable Buildings for More Sustainable Housing: Energy Life Cycle Analysis
Authors: Rafael Santos Fischer, Aloísio Leoni Schmid, Amanda Dalla-Bonna
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The life cycle analysis and the energy life cycle analysis are useful design support tools when sustainability becomes imperative. The final phase of buildings life cycle is probably the least known, on which less knowledge is available. In the Brazilian building industry, the lifespan of a building design rarely is treated as a definite design parameter. There is rather a common sense attitude to take any building demands as permanent, and to take for granted that buildings solutions are durable and solid. Housing, being a permanent issue in any society, presents a real challenge to the choice of a design lifespan. In Brazilian history, there was a contrast of the native solutions of collective, non-durable houses built by several nomadic tribes, and the stone and masonry buildings introduced by the sedentary Portuguese conquerors. Durable buildings are commonly associated with welfare. However, social dynamics makes traditional families of both parents and children be just one of several possible arrangements. In addition, a more liberal attitude towards family leads to an increase in the number of people living in alternative arrangements. Japan is an example of country where houses have been made intentionally ephemeral since the half of 20th century. The present article presents the development of a flexible housing design solution on the basis of the Design Science Research approach. A comparison in terms of energy life cycle shows how flexibility and dematerialization may point at a feasible future for housing policies in Brazil.Keywords: adaptability, adaptable building, embodied energy, life cyclce analysis, social housing
Procedia PDF Downloads 5922979 Paleogene Syn-Rift Play Identification in Palembang Sub-Basin, South Sumatera, Indonesia
Authors: Perdana Rakhmana Putra, Hansen Wijaya, Sri Budiyani, Muhamad Natsir, Alexis badai Samudra
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The Palembang Sub-Basin (PSB) located in southern part of South Sumatera basin (SSB) consist of half-graben complex trending N-S to NW-SE. These geometries are believe as an impact of strike-slip regime developed in Eocene-Oligocene. Generally, most of the wells in this area produced hydrocarbon from late stage of syn-rift sequences called Lower Talang Akar (LTAF) and post-rift sequences called Batu Raja Formation (BRF) and drilled to proved hydrocarbon on structural trap; three-way dip anticline, four-way dip anticline, dissected anticline, and stratigraphy trap; carbonate build-up and stratigraphic pinch out. Only a few wells reached the deeper syn-rift sequences called Lahat Formation (LAF) and Lemat Formation (LEF). The new interpretation of subsurface data was done by the tectonostratigraphy concept and focusing on syn-rift sequence. Base on seismic characteristic on basin centre, it divided into four sequences: pre-rift sequence, rift initiation, maximum rift and late rift. These sequences believed as a new exploration target on PSB mature basin. This paper will demonstrate the paleo depositional setting during Paleogene and exploration play concept of syn-rift sequence in PSB. The main play for this area consists of stratigraphic and structure play, where the stratigraphic play is Eocene-Oligocene sediment consist of LAF sandstone, LEF-Benakat formation, and LAF with pinch-out geometry. The pinch-out, lenses geometry and on-lap features can be seen on the seismic reflector and formed at the time of the syn-rift sequence. The structural play is dominated by a 3 Way Dip play related to reverse fault trap.Keywords: syn-rift, tectono-stratigraphy, exploration play, basin center play, south sumatera basin
Procedia PDF Downloads 2062978 Misconception on Multilingualism in Glorious Quran
Authors: Muhammed Unais
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The holy Quran is a pure Arabic book completely ensured the absence of non Arabic term. If it was revealed in a multilingual way including various foreign languages besides the Arabic, it can be easily misunderstood that the Arabs became helpless to compile such a work positively responding to the challenge of Allah due to their lack of knowledge in other languages in which the Quran is compiled. As based on the presence of some non Arabic terms in Quran like Istabrq, Saradiq, Rabbaniyyoon, etc. some oriental scholars argued that the holy Quran is not a book revealed in Arabic. We can see some Muslim scholars who either support or deny the presence of foreign terms in Quran but all of them agree that the roots of these words suspected as non Arabic are from foreign languages and are assimilated to the Arabic and using as same in that foreign language. After this linguistic assimilation was occurred and the assimilated non Arabic words became familiar among the Arabs, the Quran revealed as using these words in such a way stating that all words it contains are Arabic either pure or assimilated. Hence the two of opinions around the authenticity and reliability of etymology of these words are right. Those who argue the presence of foreign words he is right by the way of the roots of that words are from foreign and those who argue its absence he is right for that are assimilated and changed as the pure Arabic. The possibility of multilingualism in a monolingual book is logically negative but its significance is being changed according to time and place. The problem of multilingualism in Quran is the misconception raised by some oriental scholars that the Arabs became helpless to compile a book equal to Quran not because of their weakness in Arabic but because the Quran is revealed in languages they are ignorant on them. Really, the Quran was revealed in pure Arabic, the most literate language of the Arabs, and the whole words and its meaning were familiar among them. If one become positively aware of the linguistic and cultural assimilation ever found in whole civilizations and cultural sets he will have not any question in this respect. In this paper the researcher intends to shed light on the possibility of multilingualism in a monolingual book and debates among scholars in this issue, foreign terms in Quran and the logical justifications along with the exclusive features of Quran.Keywords: Quran, foreign Terms, multilingualism, language
Procedia PDF Downloads 4012977 Established Novel Approach for Chemical Oxygen Demand Concentrations Measurement Based Mach-Zehner Interferometer Sensor
Authors: Su Sin Chong, Abdul Aziz Abdul Raman, Sulaiman Wadi Harun, Hamzah Arof
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Chemical Oxygen Demand (COD) plays a vital role determination of an appropriate strategy for wastewater treatment including the control of the quality of an effluent. In this study, a new sensing method was introduced for the first time and developed to investigate chemical oxygen demand (COD) using a Mach-Zehner Interferometer (MZI)-based dye sensor. The sensor is constructed by bridging two single mode fibres (SMF1 and SMF2) with a short section (~20 mm) of multimode fibre (MMF) and was formed by tapering the MMF to generate evanescent field which is sensitive to perturbation of sensing medium. When the COD concentration increase takes effect will induce changes in output intensity and effective refractive index between the microfiber and the sensing medium. The adequacy of decisions based on COD values relies on the quality of the measurements. Therefore, the dual output response can be applied to the analytical procedure enhance measurement quality. This work presents a detailed assessment of the determination of COD values in synthetic wastewaters. Detailed models of the measurement performance, including sensitivity, reversibility, stability, and uncertainty were successfully validated by proficiency tests where supported on sound and objective criteria. Comparison of the standard method with the new proposed method was also conducted. This proposed sensor is compact, reliable and feasible to investigate the COD value.Keywords: chemical oxygen demand, environmental sensing, Mach-Zehnder interferometer sensor, online monitoring
Procedia PDF Downloads 4972976 Towards a Robust Patch Based Multi-View Stereo Technique for Textureless and Occluded 3D Reconstruction
Authors: Ben Haines, Li Bai
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Patch based reconstruction methods have been and still are one of the top performing approaches to 3D reconstruction to date. Their local approach to refining the position and orientation of a patch, free of global minimisation and independent of surface smoothness, make patch based methods extremely powerful in recovering fine grained detail of an objects surface. However, patch based approaches still fail to faithfully reconstruct textureless or highly occluded surface regions thus though performing well under lab conditions, deteriorate in industrial or real world situations. They are also computationally expensive. Current patch based methods generate point clouds with holes in texturesless or occluded regions that require expensive energy minimisation techniques to fill and interpolate a high fidelity reconstruction. Such shortcomings hinder the adaptation of the methods for industrial applications where object surfaces are often highly textureless and the speed of reconstruction is an important factor. This paper presents on-going work towards a multi-resolution approach to address the problems, utilizing particle swarm optimisation to reconstruct high fidelity geometry, and increasing robustness to textureless features through an adapted approach to the normalised cross correlation. The work also aims to speed up the reconstruction using advances in GPU technologies and remove the need for costly initialization and expansion. Through the combination of these enhancements, it is the intention of this work to create denser patch clouds even in textureless regions within a reasonable time. Initial results show the potential of such an approach to construct denser point clouds with a comparable accuracy to that of the current top-performing algorithms.Keywords: 3D reconstruction, multiview stereo, particle swarm optimisation, photo consistency
Procedia PDF Downloads 2072975 Anti-Inflammatory, Analgesic and Antipyretic Activity of Terminalia arjuna Roxb. Extract in Animal Models
Authors: Linda Chularojmontri, Seewaboon Sireeratawong, Suvara Wattanapitayakul
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Terminalia arjuna Roxb. (family Combretaceae) is commonly known as ‘Sa maw thet’ in Thai. The fruit is used in traditional medicine as natural mild laxatives, carminative and expectorant. Aim of the study: This research aims to study the anti-inflammatory, analgesic and antipyretic activities of Terminalia arjuna extract by using animal models in comparison to the reference drugs. Materials and Methods: The anti-inflammatory study was conducted by two experimental animal models namely ethyl phenylpropionate (EPP)-induced ear edema and carrageenan-induced paw edema. The study of analgesic activity used two methods of pain induction including acetic acid and heat-induced pain. In addition, the antipyretic activity study was performed by induced hyperthermia with yeast. Results: The results showed that the oral administration of Terminalia arjuna extract possessed acute anti-inflammatory effect in carrageenan-induced paw edema. Terminalia arjuna extract showed the analgesic activity in acetic acid-induced writhing response and heat-induced pain. This indicates its peripheral effect by inhibiting the biosynthesis and/or release of some pain mediators and some mechanism through Central nervous system. Moreover, Terminalia arjuna extract at the dose of 1000 and 1500 mg/kg body weight showed the antipyretic activity, which might be because of the inhibition of prostaglandins. Conclusion: The findings of this study indicated that the Terminalia arjuna extract possesses the anti-inflammatory, analgesic and antipyretic activities in animals.Keywords: analgesic activity, anti-inflammatory activity, antipyretic activity, Terminalia arjuna extract
Procedia PDF Downloads 2662974 Suggested Role for Neutrophil Extracellular Traps Formation in Ewing Sarcoma Immune Microenvironment
Authors: Rachel Shukrun, Szilvia Baron, Victoria Fidel, Anna Shusterman, Osnat Sher, Netanya Kollender, Dror Levin, Yair Peled, Yair Gortzak, Yoav Ben-Shahar, Revital Caspi, Sagi Gordon, Michal Manisterski, Ronit Elhasid
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Ewing sarcoma (EWS) is a highly aggressive cancer with a survival rate of 70–80% for patients with localized disease and under 30% for those with metastatic disease. Tumor-infiltrating neutrophils (TIN) can generate extracellular net-like DNA structures known as neutrophil extracellular traps (NETs). However, little is known about the presence and prognostic significance of tumor-infiltrating NETs in EWS. Herein, we investigated 46 patients diagnosed with EWS and treated in the Tel Aviv Medical Center between 2010 and 2021. TINs and NETs were identified in diagnostic biopsies of EWS by immunofluorescent. In addition, NETs were investigated in neutrophils isolated from peripheral blood samples of EWS patients at diagnosis and following neoadjuvant chemotherapy. The relationships between the presence of TINs and NETs, pathological and clinical features, and outcomes were analyzed. Our results demonstrate that TIN and NETs at diagnosis were higher in EWS patients with metastatic disease compared to those with local disease. High NETs formation at diagnosis predicted poor response to neo-adjuvant chemotherapy, relapse, and death from disease (P < .05). NETs formation in peripheral blood samples at diagnosis was significantly elevated among patients with EWS compared to pediatric controls and decreased significantly following neoadjuvant chemotherapy. In conclusion, NETs formation seems to have a role in the EWS immune microenvironment. Their presence can refine risk stratification, predict chemotherapy resistance and survival, and serve as a therapeutic target in patients with EWS.Keywords: Ewing sarcoma, tumor microenvironment, neutrophil, neutrophil extracellular traps (NETs), prognosis
Procedia PDF Downloads 692973 Dual Electrochemical Immunosensor for IL-13Rα2 and E-Cadherin Determination in Cell, Serum and Tissues from Cancer Patients
Authors: Amira ben Hassine, A. Valverde, V. Serafín, C. Muñoz-San Martín, M. Garranzo-Asensio, M. Gamella, R. Barderas, M. Pedrero, N. Raouafi, S. Campuzano, P. Yáñez-Sedeño, J. M. Pingarrón
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This work describes the development of a dual electrochemical immunosensing platform for accurate determination of two target proteins, IL-13 Receptor α2 (IL-13Rα2) and E-cadherin (E-cad). The proposed methodology is based on the use of sandwich immunosensing approaches (involving horseradish peroxidase-labeled detector antibodies) implemented onto magnetic microbeads (MBs) and amperometric transduction at screen-printed dual carbon electrodes (SPdCEs). The magnetic bioconjugates were captured onto SPdCEs and the amperometric transduction was performed using the H2O2/hydroquinone (HQ) system. Under optimal experimental conditions, the developed bio platform demonstrates linear concentration ranges of 1.0–25 and 5.0-100 ng mL-1, detection limits of 0.28 and 1.04 ng mL-1 for E-cad and IL-13Rα2, respectively, and excellent selectivity against other non-target proteins. The developed immuno-platform also offers a good reproducibility among amperometric responses provided by nine different sensors constructed in the same manner (Relative Standard Deviation values of 3.1% for E-cad and 4.3% for IL-13Rα2). Moreover, obtained results confirm the practical applicability of this bio-platform for the accurate determination of the endogenous levels of both extracellular receptors in colon cancer cells (both intact and lysed) with different metastatic potential and serum and tissues from patients diagnosed with colorectal cancer at different grades. Interesting features in terms of, simplicity, speed, portability and sample amount required to provide quantitative results, make this immuno-platform more compatible than conventional methodologies with the clinical diagnosis and prognosis at the point of care.Keywords: electrochemistry, mmunosensors, biosensors, E-cadherin, IL-13 receptor α2, cancer colorectal
Procedia PDF Downloads 1392972 Women, Quality of Life, and Infertility: The Mediating Role of Social Support and Hope
Authors: Saeideh Lotfi Nikoo, Azadeh Ghaheri, Reza Omani Samani
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Context: In most cultures around the globe, infertility is recognized as a crisis and exposed infertile couples are under psychosocial pressure. Indeed, the quality of life (QoL) for infertile women is lower in comparison with fertile control. Objective, The purpose of this study, was to investigate the impact of social support and hope on QoL in women undergoing infertility treatment. Methods: A cross-sectional study. Patient(s): In this cross-sectional study, 350 infertile women were recruited who were referred to an infertility clinic for the first time and had no history of Assisted Reproductive Techniques (ART) failure. Intervention(s): Questionnaires on the Fertility Quality of Life (FertiQoL), Multi-dimensional Scale of Perceived Social Support (family and friends), and Snyder Hope Scale (pathway and agency) were used to collect data. Data analysis was done by univariate and multivariate analysis. P value <0.05 was considered statistically significant. Result(s): Multivariate analysis indicated that infertile women with a higher score of social support (by family & friends) (b= 0.59 (CI 95%: 0.03, 1.15) (P = 0.040), b= 0.61 (CI 95%: 0.17, 1.04) (P = 0.006)) and hope (pathway & agency) (b= 0.94 (CI 95%: 0.29, 1.59) (P = 0.005), b= 1.13 (CI 95%: 0.45, 1.82) (P = 0.001) respectively) have significantly better Core FertiQoL. The result revealed that social support and hope are significantly and positively associated with other subscales of FertiQoL as well. Conclusions: According to the results, lifestyle interventions such as receiving social support, building a sound family with effective communication, and providing appropriate health education are of crucial importance to address psychological distress and improve the fertility QoL of women experiencing fertility problems.Keywords: inertility, social support, infertile women, hope
Procedia PDF Downloads 1002971 Environmental and Safety Studies for Advanced Fuel Cycle Fusion Energy Systems: The ESSENTIAL Approach
Authors: Massimo Zucchetti
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In the US, the SPARC-ARC projects of compact tokamaks are being developed: both are aimed at the technological demonstration of fusion power reactors with cutting-edge technology but following different design approaches. However, they show more similarities than differences in the fuel cycle, safety, radiation protection, environmental, waste and decommissioning aspects: all reactors, either experimental or demonstration ones, have to fulfill certain "essential" requirements to pass from virtual to real machines, to be built in the real world. The paper will discuss these "essential" requirements. Some of the relevant activities in these fields, carried out by our research group (ESSENTIAL group), will be briefly reported, with the aim of showing some methodology aspects that have been developed and might be of wider interest. Also, a non-competitive comparison between our results for different projects will be included when useful. The question of advanced D-He3 fuel cycles to be used for those machines will be addressed briefly. In the past, the IGNITOR project of a compact high-magnetic field D-T ignition experiment was found to be able to sustain limited D-He3 plasmas, while the Candor project was a more decisive step toward D-He3 fusion reactors. The following topics will be treated: Waste management and radioactive safety studies for advanced fusion power plants; development of compact high-field advanced fusion reactors; behavior of nuclear materials under irradiation: neutron-induced radioactivity due to side DT reactions, radiation damage; accident analysis; reactor siting.Keywords: advanced fuel fusion reactors, deuterium-helium3, high-field tokamaks, fusion safety
Procedia PDF Downloads 852970 Micro-Scale Digital Image Correlation-Driven Finite Element Simulations of Deformation and Damage Initiation in Advanced High Strength Steels
Authors: Asim Alsharif, Christophe Pinna, Hassan Ghadbeigi
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The development of next-generation advanced high strength steels (AHSS) used in the automotive industry requires a better understanding of local deformation and damage development at the scale of their microstructures. This work is focused on dual-phase DP1000 steels and involves micro-mechanical tensile testing inside a scanning electron microscope (SEM) combined with digital image correlation (DIC) to quantify the heterogeneity of deformation in both ferrite and martensite and its evolution up to fracture. Natural features of the microstructure are used for the correlation carried out using Davis LaVision software. Strain localization is observed in both phases with tensile strain values up to 130% and 110% recorded in ferrite and martensite respectively just before final fracture. Damage initiation sites have been observed during deformation in martensite but could not be correlated to local strain values. A finite element (FE) model of the microstructure has then been developed using Abaqus to map stress distributions over representative areas of the microstructure by forcing the model to deform as in the experiment using DIC-measured displacement maps as boundary conditions. A MATLAB code has been developed to automatically mesh the microstructure from SEM images and to map displacement vectors from DIC onto the FE mesh. Results show a correlation of damage initiation at the interface between ferrite and martensite with local principal stress values of about 1700MPa in the martensite phase. Damage in ferrite is now being investigated, and results are expected to bring new insight into damage development in DP steels.Keywords: advanced high strength steels, digital image correlation, finite element modelling, micro-mechanical testing
Procedia PDF Downloads 149