Search results for: Design techniques
2870 Shape Memory Alloy Structural Damper Manufactured by Selective Laser Melting
Authors: Tiziana Biasutti, Daniela Rigamonti, Lorenzo Palmiotti, Adelaide Nespoli, Paolo Bettini
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Aerospace industry is based on the continuous development of new technologies and solutions that allows constant improvement of the systems. Shape Memory Alloys are smart materials that can be used as dampers due to their pseudoelastic effect. The purpose of the research was to design a passive damper in Nitinol, manufactured by Selective Laser Melting, for space applications to reduce vibration between different structural parts in space structures. The powder is NiTi (50.2 at.% of Ni). The structure manufactured by additive technology allows us to eliminate the presence of joint and moving parts and to have a compact solution with high structural strength. The designed dampers had single or double cell structures with three different internal angles (30°, 45° and 60°). This particular shape has damping properties also without the pseudoelastic effect. For this reason, the geometries were reproduced in different materials, SS316L and Ti6Al4V, to test the geometry loss factor. The mechanical performances of these specimens were compared to the ones of NiTi structures, pointing out good damping properties of the designed structure and the highest performances of the NiTi pseudoelastic effect. The NiTi damper was mechanically characterized by static and dynamic tests and with DSC and microscope observations. The experimental results were verified with numerical models and with some scaled steel specimens in which optical fibers were embedded. The realized structure presented good mechanical and damping properties. It was observed that the loss factor and the dissipated energy increased with the angles of the cells.Keywords: additive manufacturing, damper, nitinol, pseudo elastic effect, selective laser melting, shape memory alloys
Procedia PDF Downloads 1112869 Prevalence of SARS-CoV-2 Infection and Associated Risk Factors in Selected Health Facilities of Tigray, Ethiopia: Cross-Sectional Study Design, 2023
Authors: Weldegerima Gebremedhin Hagos
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Background: The Coronavirus disease of 2019 (COVID-19) is a catastrophic emerging global health threat caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). COVID-19 has a wide range of complications and sequels. It is devastating in developing countries, causing serious health and socioeconomic crises as a result of the increasingly overburdened healthcare system. Ethiopia reported the first case of SARS-CoV-2 on 13th March 2020, with community transmission ensuing by mid-May. The aim of this study was conducted to determine the prevalence of SARS-CoV-2 infection in Tigray, Ethiopia. Methods: Facility-based correctional study designs were used on a total of 380 study participants from March 2023 up to May 2023 in two general hospitals and one comprehensive specialized hospital in Tigray, Ethiopia. A pre-structured questionnaire was used to assess information regarding the socio-demographic, clinical data and other risk factors. A nasal swap was taken by trained health professionals, and the laboratory analysis was done by RT-PCR (quant studio 7-flex, applied biosystems) in Tigrai Health Research Institute and Mekelle University Medical Microbiology Research Laboratory. Result: The mean age of the study participants was 31 (SD+/-3.5) years, with 65% being male and 35% female. The overall seropositivity of sars-cov-2 among the study participants was 5.5%. The prevalence was higher in males (6.2%) than females which were (4.7%). Sars-cov-2 infection was significantly associated with a history of lack of vaccination (p-value 0.002). There was no significant association between seropositivity and demographic factors (P > 0.05). Conclusion: The seroprevalence of SARS-CoV-2 among the study participants is high. Those study participants with a previous history of vaccination have a low probability of developing COVID-19 infection. A low SARS-CoV-2 infection rate was recorded in those who frequently use masks.Keywords: prevalence, SARS-CoV-2, infection, risk factors
Procedia PDF Downloads 632868 Governance Challenges of Consolidated Destinations. The Case of Barcelona
Authors: Montserrat Crespi-Vallbona; Oscar Mascarilla-Miró
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Mature destinations have different challenges trying to attract tourism and please its citizens. Hence, they have to maintain their touristic interest to standard demand and also not to undeceive those tourists with more advanced experiences. Second, they have to be concerned for the daily life of citizens and avoid the negative effects of touristification. This balance is quite delicate and often has to do with the sensitivity and commitment of the party in the local government. However, what is a general consensus is the need for destinations to differentiate from the homogeneous rest of regions and create new content, consumable resources or marketing events to guarantee their positioning. In this sense, the main responsibility of destinations is to satisfy users, tourists and citizens. Hence, its aim has to do with holistic experiences, which collect these wide approaches. Specifically, this research aims to analyze the volume and growth of tourist houses in the central touristic neighborhoods of Barcelona (this is Ciutat Vella) as the starting point to identify the behavior of tourists regarding their interests in searching for local heritage attractiveness and community atmosphere. Then, different cases are analyzed in order to show how Barcelona struggles to keep its attractive brand for the visitors, as well as for its inhabitants. Methodologically, secondary data used in this research comes from official registered tourist houses (Catalunya Government), Open Data (Barcelona municipality), the Airbnb tourist platform, from the Incasol Data and Municipal Register of Inhabitants. Primary data are collected through in-depth interviews with neighbors, social movement managers and political representatives from Turisme de Barcelona (local DMO, Destination Management Organization). Results show what the opportunities and priorities are for key actors to design policies to find a balance between all different interests.Keywords: touristification, tourist houses, governance, tourism demand, airbnbfication
Procedia PDF Downloads 712867 Relationship between Pain, Social Support and Socio-Economic Indicators in Individuals with Spinal Cord Injury
Authors: Zahra Khazaeipour, Ehsan Ahmadipour, Vafa Rahimi-Movaghar, Fereshteh Ahmadipour
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Research Objectives: Chronic pain is one of the common problems associated with spinal cord injuries (SCI), which causes many complications. Therefore, this study intended to evaluate the relationship between pain and demographic, injury characteristics, socio-economic and social support in individuals with spinal cord Injury in Iran. Design: Descriptive cross-sectional study. Setting: Brain and Spinal Cord Injury Research Center (BASIR), Tehran University of Medical Sciences, Tehran, Iran, between 2012 and 2013. Participants: The participants were 140 individuals with SCI, 101 (72%) men and 39 (28%) women, with mean age of 29.4 ±7.9 years. Main Outcome Measure: The Persian version of the Brief Pain Inventory (BPI) was used to measure the pain, and the Multidimensional Scale of Perceived Social Support (MSPSS) was used to measure social support. Results: About 50.7% complained about having pain, which 79.3% had bilateral pain. The most common locations of pain were lower limbs and back. The most quality of pain was described as aching (41.4%), and tingling (32.9%). Patients with a medium level of education had the least pain compared to high and low level of education. SCI individuals with good economic situation reported higher frequency of having pain. There was no significant relationship between pain and social support. There was positive correlation between pain and impairment of mood, normal work, relations with other people and lack of sleep (P < 0.001). Conclusion: These findings revealed the importance of socioeconomic factors such as economic situation and educational level in understanding chronic pain in people with SCI and provide further support for the bio-psychosocial model. Hence, multidisciplinary evaluations and treatment strategies are advocated, including biomedical, psychological, and psycho-social interventions.Keywords: pain, social support, socio-economic indicators, spinal cord injury
Procedia PDF Downloads 3012866 Screening Psychological Wellness in a South African Banking Industry: Psychometric Properties of the Sense of Coherence-29 Questionnaire and Multifactor Leadership Questionnaire
Authors: Nisha Harry, Keshia Sing
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Orientation: The Multifactor Leadership Questionnaire (MLF) and the sense of coherence-29 (SCS) is an effective tools to assess the prevalence and underlying structures of empirically based taxonomies related to leadership and wellbeing. Research purpose: The purpose of the study was to test the psychometric properties of the SCS and Multifactor Leadership Questionnaire (MLQ) to screen for psychological wellness indices within the banking industry in South Africa. Motivation for the study: The contribution of these two instruments for the purpose of determining psychological wellness in a banking work environment is unique. Research design, approach, or method: The sample consisted of (N = 150) financial staff employed in a South African banking organisation. The age of the sample was: 37% (30 -40 yrs), 31% (20-30 yrs), 26% (40- 50 yrs), and 6% (50+yrs), of which 52% were males, 48% were females. The white race group was the majority at 29%, African at 26%, Coloured at 23%, and Indian was 22%. Main findings: Results from the exploratory factor analysis revealed a two-factor structure as the most satisfactory. Confirmatory factor analyses revealed the two-factor model displayed better good of-fit indices. Practical implications: The factor structure of the Sense of Coherence-29 scale (SCS), and the Multifactor Leadership Questionnaire (MLQ), have a value-added focus to determine psychological wellness within banking staff. It is essential to take into account these constructs when developing employee wellness interventions. Contribution/value add: Understanding the psychometric properties of the SCS, the self-reported form, and the MLQ questionnaire contributes to screening psychological wellness indices such as coping within the banking industry in a developing country like South Africa. Leaders are an important part of the implementation process of organisational employee wellness practices.Keywords: factorial structure, leadership, measurement invariance, psychological wellness, sense of coherence
Procedia PDF Downloads 1162865 A Long Short-Term Memory Based Deep Learning Model for Corporate Bond Price Predictions
Authors: Vikrant Gupta, Amrit Goswami
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The fixed income market forms the basis of the modern financial market. All other assets in financial markets derive their value from the bond market. Owing to its over-the-counter nature, corporate bonds have relatively less data publicly available and thus is researched upon far less compared to Equities. Bond price prediction is a complex financial time series forecasting problem and is considered very crucial in the domain of finance. The bond prices are highly volatile and full of noise which makes it very difficult for traditional statistical time-series models to capture the complexity in series patterns which leads to inefficient forecasts. To overcome the inefficiencies of statistical models, various machine learning techniques were initially used in the literature for more accurate forecasting of time-series. However, simple machine learning methods such as linear regression, support vectors, random forests fail to provide efficient results when tested on highly complex sequences such as stock prices and bond prices. hence to capture these intricate sequence patterns, various deep learning-based methodologies have been discussed in the literature. In this study, a recurrent neural network-based deep learning model using long short term networks for prediction of corporate bond prices has been discussed. Long Short Term networks (LSTM) have been widely used in the literature for various sequence learning tasks in various domains such as machine translation, speech recognition, etc. In recent years, various studies have discussed the effectiveness of LSTMs in forecasting complex time-series sequences and have shown promising results when compared to other methodologies. LSTMs are a special kind of recurrent neural networks which are capable of learning long term dependencies due to its memory function which traditional neural networks fail to capture. In this study, a simple LSTM, Stacked LSTM and a Masked LSTM based model has been discussed with respect to varying input sequences (three days, seven days and 14 days). In order to facilitate faster learning and to gradually decompose the complexity of bond price sequence, an Empirical Mode Decomposition (EMD) has been used, which has resulted in accuracy improvement of the standalone LSTM model. With a variety of Technical Indicators and EMD decomposed time series, Masked LSTM outperformed the other two counterparts in terms of prediction accuracy. To benchmark the proposed model, the results have been compared with traditional time series models (ARIMA), shallow neural networks and above discussed three different LSTM models. In summary, our results show that the use of LSTM models provide more accurate results and should be explored more within the asset management industry.Keywords: bond prices, long short-term memory, time series forecasting, empirical mode decomposition
Procedia PDF Downloads 1402864 Effects of Bed Type, Corm Weight and Lifting Time on Quantitative and Qualitative Criteria of Saffron (Crocus sativus L.)
Authors: A. Mollafilabi, A. Koocheki, P. Rezvani Moghaddam, M. Nassiri Mahalati
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In order to study the effects of corm weights and times of corm lifting saffron in different planting beds, an experiment was conducted as Factorial layout based on a Randomized Complete Block Design with three replications at the Fadak Research Center of Agricultural Research in Food Science during 2010. Treatments were two corm weights (8-10, 10 < g), two planting beds (stone wool and peat moss) and five levels of lifting time (mi-June, early July, mid-July, early August and mid-August). No. of corms were 457 corms.m-2 and for 40 days and were stored for 90 days in incubation, 85% relative humidity and 25°C temperature in the darkness. Then, saffron corms were transferred to growth chamber with 17 °C in 8 hours light and 16 hours darkness. Characteristics were number of flower, fresh weight of flower, dry weight of flower, fresh and dry weight of stigma, fresh and dry weight of style, fresh and dry weight of stigma+style and Picrocrocin, Safronal and Crocin contents of saffron were measured. Results showed that the corm weight, bed type and time of corm lifting had significant effects on economical yield of saffron such as picked flowers, dry weight of stigma and fresh weight of flowers. The highest saffron economical yield was obtained in interaction of corm weight, 10 g, peat moss and lifting time in mid-June as much as 5.2 g.m-2. This yield is 11 fold of average yield of Iranian farms. Picrocrocin, Safranal and Crocin contents was graded as excellent thread in peat moss under controlled conditions compared with ISO Standard of 203.Keywords: corm density, dry stigma, safranal-flowering, yield saffron
Procedia PDF Downloads 3362863 Paradigm Shift in Reducing Greenhouse Gas Emissions for Developing Countries: Focus on Behavioral Changes
Authors: Bishal Saha, Musah Ahmed Rufai Muhyedeen, Jubeyer Hossain Joy, Muhammad Muhitur Rahman, Mohammad Shahedur Rahman, Md Arif Hasan, Syed Masiur Rahman
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Greenhouse gas (GHG) emission is one of the critical problems of today’s world. Many countries have been taking many short- and long-term plans to reduce climate change mitigation. However, the potential of behavioral changes in addressing this problem is promising, as reported by many researchers. This paper presents a comprehensive literature review that focuses on ways to influence people’s behavior in their homes, workplace, and transportation to mitigate the emission directly or indirectly. This study will investigate different theories pertinent to planned behavior and the key elements for modifying behavior like biophilia, reinforcement to use optimum energy and recyclable products, proper application of greenhouse tax, modern technology, and sustainable design adaptation, transportation sharing, social and community norms, proper education and information, and financial incentives. There is a number of challenges associated with behavioral changes. Behavioral interventions have different actions varied by their type and need to combine various policy tools and great social marketing. Many interventions can reduce GHG emissions without any compromise with household well-being. This study will develop a landscape of prevailing theories of environmental psychology by identifying and reviewing the key themes and findings of this field of study. It will support especially the developing countries to reduce GHG emissions without significant capital investment. It is also expected that the behavioral changes will lead to the successful adoption of climate-friendly policies easily. This study will also generate new research questions and directions.Keywords: behavioral changes, climate change mitigation, environmental psychology, greenhouse gas emission
Procedia PDF Downloads 2412862 The LEROS 4: A High Thrust Spacecraft Engine for Interplanetary Applications
Authors: I. Coxhill, P. Stiles, R. Westcott
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This paper provides a comprehensive overview of the LEROS 4 high-thrust apogee engine, intended for use on interplanetary spacecraft. The LEROS 4 rocket engine is a nominal 1.05 kN thrust engine, burning MMH and MON-3 with an Isp of >317s. The engine can be considered an enhanced thrust version of the conventional ~400N apogee engines used on many telecommunication platforms. The motivation for the development of this engine was the need for high-performance, high-thrust propulsion, particularly where gravity losses are high - typical of interplanetary maneuvers. There are a limited number of commercially available engines in the ~1kN class with a high specific impulse. The LEROS 4 engine aimed to fill this gap and provide a flexible engine for high-thrust applications. Two variants of the engine were developed out of the main programme: the LEROS 4 and the LEROS 4-ET. Whilst the LEROS 4 has a nominal thrust of 1.05kN, the ET (Extended Thrust) version operates at a nominal 1.31 kN, albeit at higher inlet pressure. This paper charts the design and development of the engine through the initial concepts, hot fire testing at sea level, hot fire testing at altitude, all the way through to engine qualification for ESA (European Space Agency). In addition to the engine itself, the test facilities in which the engine is tested are discussed. As the LEROS 4 has an unusual thrust level, there are few facilities in the world that can efficiently test an engine at this thrust level. Accordingly, Nammo designed and built a vacuum test facility that allows testing up to 1.5kN of thrust to accommodate the LEROS 4 program. Some unique features of this test facility are explained in the paper. The paper also discusses the in-flight experience of the inaugural flight (the LEROS 4-ET on board the Firefly Blue Ghost lunar lander) and the ongoing LEROS-4 qualification program for ESA, targeted at the EnVision mission to Venus. Finally, the paper summarises the achievements to date and presents a detailed specification of the performance capability.Keywords: apogee, hypergolic, interplanetary, MMH, MON-3, rocket engine, spacecraft
Procedia PDF Downloads 02861 Numerical Analysis of the Flexural Behaviour of Concrete-Filled Rectangular Flange Girders
Authors: R. Al-Dujele, K. A. Cashell
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A tubular flange girder is an I-shaped steel girder with either one of both of the usual flat flange plates replaced with a hollow section. Typically, these hollow sections are either rectangular or circular in shape. Concrete filled tubular flange girders (CFTFGs) are unconventional I-shaped beams that use a hollow structural section as the top flange which is filled with concrete. The resulting section offers very high lateral torsional buckling strength and stiffness compared with conventional steel I-beams of similar depth, width and weight, typically leading to a reduction in lateral bracing requirements. This paper is focussed on investigating the ultimate capacity of concrete filled rectangular tubular flange girders (CFRTFGs). These are complex members and their behaviour is governed by a number of inter-related parameters. The FE model is developed using ABAQUS software, 3-D finite element (FE) model for simply supported CFRTFGs subjected to two point loads applied at the third-span points is built. An initial geometrical imperfection of (L/1000), as well as geometrical and material nonlinearities, are introduced into the model, where L denotes the span of the girder. In this numerical model, the concrete and steel materials are modelled using eight-node solid and four-node shell elements, respectively. In addition to the FE model, simplified analytical expressions for the flexural capacity are also proposed, and the results are compared to those from the FE analyses. The analytical expressions, which are suitable for design, are also shown to be capable of providing an accurate depiction of the bending moment capacity.Keywords: concrete-filled rectangular tubular flange girders, ultimate capacity, confining effect, finite element analysis
Procedia PDF Downloads 1482860 Racial and Ethnic Health Disparities: An Investigation of the Relationship between Race, Ethnicity, Health Care Access, and Health Status
Authors: Dorcas Matowe
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Inequality in health care for racial and ethnic minorities continues to be a growing concern for many Americans. Some of the barriers hindering the elimination of health disparities include lack of insurance, socioeconomic status (SES), and racism. This study will specifically focus on the association between some of these factors- health care access, which includes insurance coverage and frequency of doctor visits, race, ethnicity, and health status. The purpose of this study will be to address the following questions: is having health insurance associated with increased doctor visits? Are racial and ethnic minorities with health insurance more or less likely to see a doctor? Is the association between having health insurance moderated by being an ethnic minority? Given the current implications of the 2010 Affordable Care Act, this study will highlight the need to prioritize health care access for minorities and confront institutional racism. Critical Race Theory (CRT) will demonstrate how racism has reinforced these health disparities. This quantitative study design will analyze secondary data from the 2015 Behavioral Risk Factor Surveillance System (BRFSS) questionnaire, a telephone survey conducted annually in all 50 states and three US territories by state health departments in conjunction with the Center for Disease Control (CDC). Non-identifying health-related data is gathered annually from over 400,000 adults 18 years and above about their health status and use of preventative services. Through Structural Equation Modeling (SEM), the relationship between the predictor variables of health care access, race, and ethnicity, the criterion variable of health status, and the latent variables of emotional support and life satisfaction will be examined. It is hypothesized that there will be an interaction between certain racial and ethnic minorities who went to see a doctor, had insurance coverage, experienced racism, and the quality of their health status, emotional support, and life satisfaction.Keywords: ethnic minorities, health disparities, health access, racism
Procedia PDF Downloads 2762859 Relationship Between Reading Comprehension and Achievement in Science Among Grade Eleven Bilingual Students in a Secondary School, Thailand
Authors: Simon Mauma Efange
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The main aims of this research were to describe, in co-relational terms, the relationship, if any, between reading comprehension and academic achievement in science studied at the secondary level and, secondly, to find out possible trends in gender differences, such as whether boys would perform better than girls or vice versa. This research employed a quantitative design. Two kinds of instruments were employed: the Oxford Online Placement Test and the Local Assessment System Test. The Oxford Online Placement Test assesses students' English level quickly and easily. The results of these tests were subjected to statistical analysis using a special statistical software called SPSS. Statistical tools such as mean, standard deviation, percentages, frequencies, t-tests, and Pearson’s coefficient of correlation were used for the analysis of the results. Results of the t-test showed that the means are significantly different. Calculating the p-value revealed that the results were extremely statistically significant at p <.05. The value of r (Pearson correlation coefficient) was 0.2868. Although technically there is a positive correlation, the relationship between the variables is only weak (the closer the value is to zero, the weaker the relationship). However, in conclusion, calculations from the t-test using SPSS revealed that the results were statistically significant at p <.05, confirming a relationship between the two variables, and high scores in reading will give rise to slightly high scores in science. The research also revealed that having a high score in reading comprehension doesn’t necessarily mean having a high score in science or vice versa. Female subjects performed much better than male subjects in both tests, which is in line with the literature reviewed for this research.Keywords: achievement in science, achievement in English, and bilingual students, relationship
Procedia PDF Downloads 522858 Investigation of the Effect of Lecturers' Attributes on Students' Interest in Learning Statistic Ghanaian Tertiary Institutions
Authors: Samuel Asiedu-Addo, Jonathan Annan, Yarhands Dissou Arthur
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The study aims to explore the relational effect of lecturers’ personal attribute on student’s interest in statistics. In this study personal attributes of lecturers’ such as lecturer’s dynamism, communication strategies and rapport in the classroom as well as applied knowledge during lecture were examined. Here, exploratory research design was used to establish the effect of lecturer’s personal attributes on student’s interest. Data were analyzed by means of confirmatory factor analysis and structural equation modeling (SEM) using the SmartPLS 3 program. The study recruited 376 students from the faculty of technical and vocational education of the University of Education Winneba Kumasi campus, and Ghana Technology University College as well as Kwame Nkrumah University of science and Technology. The results revealed that personal attributes of an effective lecturer were lecturer’s dynamism, rapport, communication and applied knowledge contribute (52.9%) in explaining students interest in statistics. Our regression analysis and structural equation modeling confirm that lecturers personal attribute contribute effectively by predicting student’s interest of 52.9% and 53.7% respectively. The paper concludes that the total effect of a lecturer’s attribute on student’s interest is moderate and significant. While a lecturer’s communication and dynamism were found to contribute positively to students’ interest, they were insignificant in predicting students’ interest. We further showed that a lecturer’s personal attributes such as applied knowledge and rapport have positive and significant effect on tertiary student’s interest in statistic, whilst lecturers’ communication and dynamism do not significantly affect student interest in statistics; though positively related.Keywords: student interest, effective teacher, personal attributes, regression and SEM
Procedia PDF Downloads 3612857 Modulating Plasmon Induced Transparency in Terahertz Metamaterials
Authors: Gagan Kumar, Koijam M. Devi, Amarendra K. Sarma, Dibakar Roy Chowdhury
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Research in metamaterials has been gaining momentum over the past decade owing to its ability in controlling electromagnetic wave properties through careful design at the sub-wavelength scale. The metamaterials have led to several important phenomena which are useful in a variety of applications. One such phenomenon is the electromagnetically induced transparency (EIT) effect in which a narrow transparency region is created in an otherwise absorptive spectrum. In our work, we explore plasmon induced transparency (PIT) in terahertz metamaterials which is analogues to EIT effect. The PIT effect is achieved using the plasmonic metamaterials in which a unit cell is comprised of two C (2C) shaped resonators and a cut-wire (CW). When terahertz wave of a particular polarization is normally incident on the proposed metamaterials geometry, it strongly couples with the cut wire, resulting in the excitation of the bright mode. However due to the specific polarization of the incident beam, the fundamental modes of the C-shaped resonators are not excited by the incident terahertz, hence they are termed as the dark mode. The PIT effect occurs as a result of interference between the bright and the dark mode. In order to observe PIT effect, both the bright and dark modes should have similar resonant frequencies with a little deviation. We further have examined that the PIT window can be modulated by displacing the C-shaped resonators w.r.t. the cut-wire. The numerical observations for different coupling configurations can be explained through an equivalent lumped element circuit model. Moving ahead the PIT effect is further explored in a metamaterial comprising of a cross like structure and four C-shaped resonators. For such configuration, equally strong PIT effect is observed for two orthogonally polarized lights. Therefore, such metamaterials demonstrate a polarization independent PIT response w.r.t the incident terahertz radiation. The proposed study could be significant in the development of slow light devices and polarization independent sensing applications.Keywords: terahertz, metamaterial, split ring resonator, plasmon
Procedia PDF Downloads 2162856 Inclusion Body Refolding at High Concentration for Large-Scale Applications
Authors: J. Gabrielczyk, J. Kluitmann, T. Dammeyer, H. J. Jördening
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High-level expression of proteins in bacteria often causes production of insoluble protein aggregates, called inclusion bodies (IB). They contain mainly one type of protein and offer an easy and efficient way to get purified protein. On the other hand, proteins in IB are normally devoid of function and therefore need a special treatment to become active. Most refolding techniques aim at diluting the solubilizing chaotropic agents. Unfortunately, optimal refolding conditions have to be found empirically for every protein. For large-scale applications, a simple refolding process with high yields and high final enzyme concentrations is still missing. The constructed plasmid pASK-IBA63b containing the sequence of fructosyltransferase (FTF, EC 2.4.1.162) from Bacillus subtilis NCIMB 11871 was transformed into E. coli BL21 (DE3) Rosetta. The bacterium was cultivated in a fed-batch bioreactor. The produced FTF was obtained mainly as IB. For refolding experiments, five different amounts of IBs were solubilized in urea buffer with protein concentration of 0.2-8.5 g/L. Solubilizates were refolded with batch or continuous dialysis. The refolding yield was determined by measuring the protein concentration of the clear supernatant before and after the dialysis. Particle size was measured by dynamic light scattering. We tested the solubilization properties of fructosyltransferase IBs. The particle size measurements revealed that the solubilization of the aggregates is achieved at urea concentration of 5M or higher and confirmed by absorption spectroscopy. All results confirm previous investigations that refolding yields are dependent upon initial protein concentration. In batch dialysis, the yields dropped from 67% to 12% and 72% to 19% for continuous dialysis, in relation to initial concentrations from 0.2 to 8.5 g/L. Often used additives such as sucrose and glycerol had no effect on refolding yields. Buffer screening indicated a significant increase in activity but also temperature stability of FTF with citrate/phosphate buffer. By adding citrate to the dialysis buffer, we were able to increase the refolding yields to 82-47% in batch and 90-74% in the continuous process. Further experiments showed that in general, higher ionic strength of buffers had major impact on refolding yields; doubling the buffer concentration increased the yields up to threefold. Finally, we achieved corresponding high refolding yields by reducing the chamber volume by 75% and the amount of buffer needed. The refolded enzyme had an optimal activity of 12.5±0.3 x104 units/g. However, detailed experiments with native FTF revealed a reaggregation of the molecules and loss in specific activity depending on the enzyme concentration and particle size. For that reason, we actually focus on developing a process of simultaneous enzyme refolding and immobilization. The results of this study show a new approach in finding optimal refolding conditions for inclusion bodies at high concentrations. Straightforward buffer screening and increase of the ionic strength can optimize the refolding yield of the target protein by 400%. Gentle removal of chaotrope with continuous dialysis increases the yields by an additional 65%, independent of the refolding buffer applied. In general time is the crucial parameter for successful refolding of solubilized proteins.Keywords: dialysis, inclusion body, refolding, solubilization
Procedia PDF Downloads 2952855 Analysis of Turkish Government Cultural Portal for Supporting Gastronomy Tourism
Authors: Hilmi Rafet Yüncü
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Today Internet has very important role to promote products and services all over the world. Companies and destinations in tourism industry use Internet to sell and to promote their core products to directly potential tourists. Internet technologies have redefined the relationships between tourists, tourism companies, and travel agents. The new relationship allows for accessing and tapping tourism information and services. Internet technologies ensure new opportunities to available for the tourism industry, including travel accommodation, and tourist destination organizations. Websites are important devices to the marketing of a destination. Most people make a research about the destination before arriving via internet. Governments have a considerable role in the process of marketing tourism destinations. Governments make policies and regulations; furthermore, they help to market destinations to potential tourists. Governments have a comprehensive overview of the sector to see changes in tourism market and design better policies, programs and marketing plans. At the same time, governments support developing of alternative tourism in the country with regulations and marketing tools. The aim of this study is to analyse of an Internet website of governmental tourism portal in Turkey to determine effectiveness about gastronomy tourism. The Turkish government has established a culture portal for foreign and local tourists. The Portal provides local and general information about tourism attractions of cities and Turkey. There are 81 official cities in Turkey and all these cities are conducted to analyse to determine how effective marketing is done by Turkish Government in the manner of gastronomy tourism. A content analysis will be conducted to Internet website of the portal with food content, recipes and gastronomic feature of cities.Keywords: culture portal, gastronomy tourism, government, Turkey
Procedia PDF Downloads 3472854 The Development of Quality Standards for the Qualification of Community Interpreters in Germany: A Needs Assessment
Authors: Jessica Terese Mueller, Christoph Breitsprecher, Mike Oliver Mosko
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Due to an unusually high number of asylum seekers entering Germany over the course of the past few years, the need for community interpreters has increased dramatically, in order to make the communication between asylum seekers and various actors in social and governmental agencies possible. In the field of social work in particular, there are community interpreters who possess a wide spectrum of qualifications spanning from state-certified professional interpreters with graduate degrees to lay or ad-hoc interpreters with little to no formal training. To the best of our knowledge, Germany has no official national quality standards for the training of community interpreters at present, which would serve to professionalise this field as well as to assure a certain degree of quality in the training programmes offered. Given the current demand for trained community interpreters, there is a growing number of training programmes geared toward qualifying community interpreters who work with asylum seekers in Germany. These training programmes range from short one-day workshops to graduate programmes with specialisations in Community Interpreting. As part of a larger project to develop quality standards for the qualification of community interpreters working with asylum seekers in the field of social work, a needs assessment was performed in the city-state of Hamburg and the state of North Rhine Westphalia in the form of focus groups and individual interviews with relevant actors in the field in order to determine the content and practical knowledge needed for community interpreters from the perspectives of those who work in and rely on this field. More specifically, social workers, volunteers, certified language and cultural mediators, paid and volunteer community interpreters and asylum seekers were invited to take part in focus groups in both locations, and asylum seekers, training providers, researchers, linguists and other national and international experts were individually interviewed. The responses collected in these focus groups and interviews have been analysed using Mayring’s concept of content analysis. In general, the responses indicate a high degree of overlap related to certain categories as well as some categories which seemed to be of particular importance to certain groups individually, while showing little to no relevance for other groups. For example, the topics of accuracy and transparency of the interpretations, as well as professionalism and ethical concerns were touched on in some form in most groups. Some group-specific topics which are the focus of experts were topics related to interpreting techniques and more concretely described theoretical and practical knowledge which should be covered in training programmes. Social workers and volunteers generally concentrated on issues regarding the role of the community interpreters and the importance of setting and clarifying professional boundaries. From the perspective of service receivers, asylum seekers tended to focus on the importance of having access to interpreters who are from their home region or country and who speak the same regiolect, dialect or variety as they do in order to prevent misunderstandings or misinterpretations which might negatively affect their asylum status. These results indicate a certain degree of consensus with trainings offered internationally for community interpreters.Keywords: asylum seekers, community interpreting, needs assessment, quality standards, training
Procedia PDF Downloads 1712853 Plasmonic Biosensor for Early Detection of Environmental DNA (eDNA) Combined with Enzyme Amplification
Authors: Monisha Elumalai, Joana Guerreiro, Joana Carvalho, Marta Prado
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DNA biosensors popularity has been increasing over the past few years. Traditional analytical techniques tend to require complex steps and expensive equipment however DNA biosensors have the advantage of getting simple, fast and economic. Additionally, the combination of DNA biosensors with nanomaterials offers the opportunity to improve the selectivity, sensitivity and the overall performance of the devices. DNA biosensors are based on oligonucleotides as sensing elements. These oligonucleotides are highly specific to complementary DNA sequences resulting in the hybridization of the strands. DNA biosensors are not only an advantage in the clinical field but also applicable in numerous research areas such as food analysis or environmental control. Zebra Mussels (ZM), Dreissena polymorpha are invasive species responsible for enormous negative impacts on the environment and ecosystems. Generally, the detection of ZM is made when the observation of adult or macroscopic larvae's is made however at this stage is too late to avoid the harmful effects. Therefore, there is a need to develop an analytical tool for the early detection of ZM. Here, we present a portable plasmonic biosensor for the detection of environmental DNA (eDNA) released to the environment from this invasive species. The plasmonic DNA biosensor combines gold nanoparticles, as transducer elements, due to their great optical properties and high sensitivity. The detection strategy is based on the immobilization of a short base pair DNA sequence on the nanoparticles surface followed by specific hybridization in the presence of a complementary target DNA. The hybridization events are tracked by the optical response provided by the nanospheres and their surrounding environment. The identification of the DNA sequences (synthetic target and probes) to detect Zebra mussel were designed by using Geneious software in order to maximize the specificity. Moreover, to increase the optical response enzyme amplification of DNA might be used. The gold nanospheres were synthesized and characterized by UV-visible spectrophotometry and transmission electron microscopy (TEM). The obtained nanospheres present the maximum localized surface plasmon resonance (LSPR) peak position are found to be around 519 nm and a diameter of 17nm. The DNA probes modified with a sulfur group at one end of the sequence were then loaded on the gold nanospheres at different ionic strengths and DNA probe concentrations. The optimal DNA probe loading will be selected based on the stability of the optical signal followed by the hybridization study. Hybridization process leads to either nanoparticle dispersion or aggregation based on the presence or absence of the target DNA. Finally, this detection system will be integrated into an optical sensing platform. Considering that the developed device will be used in the field, it should fulfill the inexpensive and portability requirements. The sensing devices based on specific DNA detection holds great potential and can be exploited for sensing applications in-loco.Keywords: ZM DNA, DNA probes, nicking enzyme, gold nanoparticles
Procedia PDF Downloads 2512852 Exploring Program Directors’ and Faculty’s Perception and Factors Leading to Burnout in Higher Education Institutions in Azerbaijan
Authors: Gunay Imanguliyeva
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Burnout is one of the concerning issues in education. The present paper aimed to explore the concept of burnout among program directors and faculty working in three higher education institutions (HEIs) in Azerbaijan and identify the factors contributing to burnout and the possible consequences of this syndrome on research participants’ professional and personal life. The researcher believed that if the concept of burnout was defined precisely and explored among more faculty, administration, and educational institutions, university leadership may have looked for the ways to support program directors and faculty, which would increase job satisfaction and decrease turnover. An exploratory qualitative research design was chosen for this study. The conceptual framework of this study was based on the Maslach Burnout Inventory. The instruments of the research were semi-structured interviews, observation, and document review. Three EFL (Teaching English as a Foreign Language) instructors and three program directors of the English Language Department working in three higher educational institutions in Azerbaijan participated in this study. The major findings of this study showed that both program directors and faculty suffered from burnout. Though they were aware of the factors that caused burnout, they did not know how to deal with this feeling. While research participants had high feeling of Emotional Exhaustion and Depersonalization, they had a low feeling of Personal Accomplishment. The researcher suggests that further research is important to measure the level of burnout and to enable HEIs to increase the productivity of program directors’ and faculty’s work as well as decrease the rate of retention in future. Also, in order to help program directors and faculty to cope with burnout, the research recommends the university leadership to meet their psycho-social needs, emotional-physical needs, and personal-intellectual needs. Keywords: burnout, emotional exhaustion, factors, well-being, higher educationKeywords: burnout, well-being, higher education, factors
Procedia PDF Downloads 1102851 Design of an Automatic Bovine Feeding Machine
Authors: Huseyin A. Yavasoglu, Yusuf Ziya Tengiz, Ali Göksenli
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In this study, an automatic feeding machine for different type and class of bovine animals is designed. Daily nutrition of a bovine consists of grass, corn, straw, silage, oat, wheat and different vitamins and minerals. The amount and mixture amount of each of the nutrition depends on different parameters of the bovine. These parameters are; age, sex, weight and maternity of the bovine, also outside temperature. The problem in a farm is to constitute the correct mixture and amount of nutrition for each animal. Faulty nutrition will cause an insufficient feeding of the animal concluding in an unhealthy bovine. To solve this problem, a new automatic feeding machine is designed. Travelling of the machine is performed by four tires, which is pulled by a tractor. The carrier consists of eight bins, which each of them carries a nutrition type. Capacity of each unit is 250 kg. At the bottom of each chamber is a sensor measuring the weight of the food inside. A funnel is at the bottom of each chamber by which open/close function is controlled by a valve. Each animal will carry a RFID tag including ID on its ear. A receiver on the feeding machine will read this ID and by given previous information by the operator (veterinarian), the system will detect the amount of each nutrition unit which will be given to the selected animal for feeding. In the system, each bin will open its exit gate by the help of the valve under the control of PLC (Programmable Logic Controller). The amount of each nutrition type will be controlled by measuring the open/close time. The exit canals of the bins are collected in a reservoir. To achieve a homogenous nitration, the collected feed will be mixed by a worm gear. Further the mixture will be transported by a help of a funnel to the feeding unit of the animal. The feeding process can be performed in 100 seconds. After feeding of the animal, the tractor pulls the travelling machine to the next animal. By the help of this system animals can be feeded by right amount and mixture of nutritionKeywords: bovine, feeding, nutrition, transportation, automatic
Procedia PDF Downloads 3442850 Response of Different Mulch Materials on Cowpea (Vigna unguiculata ) Growth and Yield in Tolon District
Authors: Adu Micheal Kwaku, Lamptey Shirley
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Cowpea (Vigna unguiculata (L.) Walpis) is a major food grain legume in Ghana and plays a significant role in consumer diets. Drought in rain-fed crop production is known to cause substantial crop yield reduction due to their negative impacts on plant growth, physiology, and reproduction. There are various ways of reducing the effect of drought or addressing the problem of drought stress, including irrigation, breeding, and mulching. Among these three ways of reducing the effect of drought stress, the cheapest and quickest method is mulching. The broad objective of this project is to determine the influence of mulching on the performance of cowpea. The experiment was conducted at Planting for future garden located at Nyankpala Campus of the University for Development Studies (UDS), comprising five treatments (black plastic, rice hull, groundnut hull, dry grass mulch, and control). The treatments were evaluated in a Randomized Complete Block Design (RCBD) with three replications. The result shows that black plastic mulch increased soil moisture by 1, 8, 15, and 24% compared to rice hull, groundnut hull, dry grass, and control, respectively. Increased soil moisture translated into black plastic mulch increasing grain yield by 8, 25, 39, and 46% compared to groundnut hull, rice hull, dry grass and control, respectively. However, black plastic mulch increased the cost of production, resulting in decreased net returns compared to the other treatment. This study recommends the use of rice and groundnut hull as mulching material to improve soil moisture, grain yield, and profit of smallholder cowpea farmers and also because they are almost free and available.Keywords: mulch, plastic mulch, cowpea, growth response
Procedia PDF Downloads 962849 4D Monitoring of Subsurface Conditions in Concrete Infrastructure Prior to Failure Using Ground Penetrating Radar
Authors: Lee Tasker, Ali Karrech, Jeffrey Shragge, Matthew Josh
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Monitoring for the deterioration of concrete infrastructure is an important assessment tool for an engineer and difficulties can be experienced with monitoring for deterioration within an infrastructure. If a failure crack, or fluid seepage through such a crack, is observed from the surface often the source location of the deterioration is not known. Geophysical methods are used to assist engineers with assessing the subsurface conditions of materials. Techniques such as Ground Penetrating Radar (GPR) provide information on the location of buried infrastructure such as pipes and conduits, positions of reinforcements within concrete blocks, and regions of voids/cavities behind tunnel lining. This experiment underlines the application of GPR as an infrastructure-monitoring tool to highlight and monitor regions of possible deterioration within a concrete test wall due to an increase in the generation of fractures; in particular, during a time period of applied load to a concrete wall up to and including structural failure. A three-point load was applied to a concrete test wall of dimensions 1700 x 600 x 300 mm³ in increments of 10 kN, until the wall structurally failed at 107.6 kN. At each increment of applied load, the load was kept constant and the wall was scanned using GPR along profile lines across the wall surface. The measured radar amplitude responses of the GPR profiles, at each applied load interval, were reconstructed into depth-slice grids and presented at fixed depth-slice intervals. The corresponding depth-slices were subtracted from each data set to compare the radar amplitude response between datasets and monitor for changes in the radar amplitude response. At lower values of applied load (i.e., 0-60 kN), few changes were observed in the difference of radar amplitude responses between data sets. At higher values of applied load (i.e., 100 kN), closer to structural failure, larger differences in radar amplitude response between data sets were highlighted in the GPR data; up to 300% increase in radar amplitude response at some locations between the 0 kN and 100 kN radar datasets. Distinct regions were observed in the 100 kN difference dataset (i.e., 100 kN-0 kN) close to the location of the final failure crack. The key regions observed were a conical feature located between approximately 3.0-12.0 cm depth from surface and a vertical linear feature located approximately 12.1-21.0 cm depth from surface. These key regions have been interpreted as locations exhibiting an increased change in pore-space due to increased mechanical loading, or locations displaying an increase in volume of micro-cracks, or locations showing the development of a larger macro-crack. The experiment showed that GPR is a useful geophysical monitoring tool to assist engineers with highlighting and monitoring regions of large changes of radar amplitude response that may be associated with locations of significant internal structural change (e.g. crack development). GPR is a non-destructive technique that is fast to deploy in a production setting. GPR can assist with reducing risk and costs in future infrastructure maintenance programs by highlighting and monitoring locations within the structure exhibiting large changes in radar amplitude over calendar-time.Keywords: 4D GPR, engineering geophysics, ground penetrating radar, infrastructure monitoring
Procedia PDF Downloads 1812848 Microbubbles Enhanced Synthetic Phorbol Ester Degradation by Ozonolysis
Authors: D. Kuvshinov, A. Siswanto, W. Zimmerman
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A phorbol-12-myristate-13-acetate (TPA) is a synthetic analogue of phorbol ester (PE), a natural toxic compound of Euphorbiaceae plant. The oil extracted from plants of this family is useful source for primarily biofuel. However this oil can also be used as a food stock due to its significant nutrition content. The limitations for utilizing the oil as a food stock are mainly due to a toxicity of PE. Nowadays a majority of PE detoxification processes are expensive as include multi steps alcohol extraction sequence. Ozone is considered as a strong oxidative agent. It reaction with PE it attacks the carbon double bond of PE. This modification of PE molecular structure results into nontoxic ester with high lipid content. This report presents data on development of simple and cheap PE detoxification process with water application as a buffer and ozone as reactive component. The core of this new technique is a simultaneous application of new microscale plasma unit for ozone production and patented gas oscillation technology. In combination with a reactor design the technology permits ozone injection to the water-TPA mixture in form of microbubbles. The efficacy of a heterogeneous process depends on diffusion coefficient which can be controlled by contact time and interface area. The low velocity of rising microbubbles and high surface to volume ratio allow fast mass transfer to be achieved during the process. Direct injection of ozone is the most efficient process for a highly reactive and short lived chemical. Data on the plasma unit behavior are presented and influence of the gas oscillation technology to the microbubbles production mechanism has been discussed. Data on overall process efficacy for TPA degradation is shown.Keywords: microbubble, ozonolysis, synthetic phorbol ester, chemical engineering
Procedia PDF Downloads 2212847 Growth Performance, Body Linear Measurements and Body Condition Score of Savanna Brown Goats Fed Enzyme Treated Sawdust Diets as Replacement for Maize Offal and Managed Semi-intensively
Authors: Alabi Olushola John, Ogbiko Anthonia, Tsado Daniel Nma, Mbajiorgu Ejike Felix, Adama Theophilus Zubairu
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A total of thirty (30) goats weighting between 5.8 and 7.3 kg were used to determine the growth performance, body linear measurements and body condition score of Semi intensively manged Savanna Brown goats fed enzyme treated sawdust diets (ETSD). They divided into five dietary treatments (T) groups with three replications using a completely randomized design. Treatment one (1) comprises of animals fed diet on 0 % enzyme treated sawdust while Treatment 2 (T2), Treatment 3 (T3), Treatment 4 (T4) and Treatment 5 (T5) comprises of animals fed diets containing 10, 20, 30 and 40 % enzyme treated sawdust diets, respectively. The study lasted 16 weeks. Data on growth performance parameters, body linear measurement (height at wither, body length, chest girth, hind leg length, foreleg length, facial length) and body condition score were collected and analyzed using one way analysis of variance. No significant difference (p>0.05) was observed in the all growth performance parameters and linear body measurements. However, significant difference was observed in body length and daily body length gains with highest value observed in animals fed the control diets (7.38 and 0.08 cm respectively) and animals on 30 % ETSD (7.25 and 0.07 cm respectively) and lowest values (4.75 and 0.05 cm respectively) were observed in animals fed 10 % ETSD among the treatment groups. It was, therefore, concluded that enzyme treated sawdust can be used in the diets of Savanna Brown goats up to 40 % replacement for maize offal since this treatment improved the body length and daily body length gains.Keywords: performance, sawdust, enzyme treated, semi-intensively, replacement
Procedia PDF Downloads 1102846 A Policy Strategy for Building Energy Data Management in India
Authors: Shravani Itkelwar, Deepak Tewari, Bhaskar Natarajan
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The energy consumption data plays a vital role in energy efficiency policy design, implementation, and impact assessment. Any demand-side energy management intervention's success relies on the availability of accurate, comprehensive, granular, and up-to-date data on energy consumption. The Building sector, including residential and commercial, is one of the largest consumers of energy in India after the Industrial sector. With economic growth and increasing urbanization, the building sector is projected to grow at an unprecedented rate, resulting in a 5.6 times escalation in energy consumption till 2047 compared to 2017. Therefore, energy efficiency interventions will play a vital role in decoupling the floor area growth and associated energy demand, thereby increasing the need for robust data. In India, multiple institutions are involved in the collection and dissemination of data. This paper focuses on energy consumption data management in the building sector in India for both residential and commercial segments. It evaluates the robustness of data available through administrative and survey routes to estimate the key performance indicators and identify critical data gaps for making informed decisions. The paper explores several issues in the data, such as lack of comprehensiveness, non-availability of disaggregated data, the discrepancy in different data sources, inconsistent building categorization, and others. The identified data gaps are justified with appropriate examples. Moreover, the paper prioritizes required data in order of relevance to policymaking and groups it into "available," "easy to get," and "hard to get" categories. The paper concludes with recommendations to address the data gaps by leveraging digital initiatives, strengthening institutional capacity, institutionalizing exclusive building energy surveys, and standardization of building categorization, among others, to strengthen the management of building sector energy consumption data.Keywords: energy data, energy policy, energy efficiency, buildings
Procedia PDF Downloads 1872845 Photophysics and Torsional Dynamics of Thioflavin T in Deep Eutectic Solvents
Authors: Rajesh Kumar Gautam, Debabrata Seth
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Thioflavin-T (ThT) play a key role of an important biologically active fluorescent sensor for amyloid fibrils. ThT molecule has been developed a method to detect the analysis of different type of diseases such as neurodegenerative disorders, Alzheimer’s, Parkinson’s, and type II diabetes. ThT was used as a fluorescent marker to detect the formation of amyloid fibril. In the presence of amyloid fibril, ThT becomes highly fluorescent. ThT undergoes twisting motion around C-C bonds of the two adjacent benzothiazole and dimethylaniline aromatic rings, which is predominantly affected by the micro-viscosity of the local environment. The present study articulates photophysics and torsional dynamics of biologically active molecule ThT in the presence of deep-eutectic solvents (DESs). DESs are environment-friendly, low cost and biodegradable alternatives to the ionic liquids. DES resembles ionic liquids, but the constituents of a DES include a hydrogen bond donor and acceptor species, in addition to ions. Due to the presence of the H-bonding network within a DES, it exhibits structural heterogeneity. Herein, we have prepared two different DESs by mixing urea with choline chloride and N, N-diethyl ethanol ammonium chloride at ~ 340 K. It was reported that deep eutectic mixture of choline chloride with urea gave a liquid with a freezing point of 12°C. We have experimented by taking two different concentrations of ThT. It was observed that at higher concentration of ThT (50 µM) it forms aggregates in DES. The photophysics of ThT as a function of temperature have been explored by using steady-state, and picoseconds time-resolved fluorescence emission spectroscopic techniques. From the spectroscopic analysis, we have observed that with rising temperature the fluorescence quantum yields and lifetime values of ThT molecule gradually decreases; this is the cumulative effect of thermal quenching and increase in the rate of the torsional rate constant. The fluorescence quantum yield and fluorescence lifetime decay values were always higher for DES-II (urea & N, N-diethyl ethanol ammonium chloride) than those for DES-I (urea & choline chloride). This was mainly due to the presence of structural heterogeneity of the medium. This was further confirmed by comparison with the activation energy of viscous flow with the activation energy of non-radiative decay. ThT molecule in less viscous media undergoes a very fast twisting process and leads to deactivation from the photoexcited state. In this system, the torsional motion increases with increasing temperature. We have concluded that beside bulk viscosity of the media, structural heterogeneity of the medium play crucial role to guide the photophysics of ThT in DESs. The analysis of the experimental data was carried out in the temperature range 288 ≤ T = 333K. The present articulate is to obtain an insight into the DESs as media for studying various photophysical processes of amyloid fibrils sensing molecule of ThT.Keywords: deep eutectic solvent, photophysics, Thioflavin T, the torsional rate constant
Procedia PDF Downloads 1662844 Protective Coating Layers via Phosphazene Compounds for Stabilizing Silicon Anode Materials
Authors: Adjmal Ghaur, Christoph Peschel, Iris Dienwiebel, Lukas Haneke, Leilei Du , Laurin Profanter, Tobias Placke, Martin Winter
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In recent years, lithium-ion batteries (LIBs)are widely used in electric vehicles (EVs) and mobile energy storage devices (ESDs), which has led to higher requirements for energy density. To fulfill these requirements, tremendous attention has been paid to design advanced LIBs with various siliconactive materials as alternative negative electrodes to replace graphite (372 mAh g⁻¹)due to their high theoretical gravimetric capacity (4200mAh g⁻¹). However, silicon as potential anode material suffers from huge volume changes during charging and discharging and has poor electronicconductivity which negatively impacts the long-term performance and preventshigh silicon contents from practical application. Additionally, an unstable crystalline silicon structure tends to pulverization during the (de)lithiation process. To compensate for the volume changes, alleviate pulverization, and maintain high electronicconductivity, silicon-doped graphite composites with protecting coating layers are a promising approach. In this context, phosphazene compounds are investigated concerning their silicon protecting properties in silicon-doped graphite composites. In detail, electrochemical performance measurements in pouch full-cells(NCM523||SiOx/C), supressing gas formation properties, and post-mortem analyzes were carried out to characterize phosphazene compounds as additive materials. The introduction of the dual-additive approach in state-of-the-art electrolytes leads to synergistic effects between FEC and phosphazene compounds which accelerate the durability of silicon particles and results in enhanced electrochemical performance.Keywords: silicon, phosphazene, solid electrolyte interphase, electrolyte, gasmeasurements
Procedia PDF Downloads 1722843 Surface Morphology and Wetting Behavior of the Aspidiotus spp. Scale Covers
Authors: Meril Kate Mariano, Billy Joel Almarinez Divina Amalin, Jose Isagani Janairo
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The scale insects Aspidiotus destructor and Aspidiotus rigidus exhibit notable scale covers made of wax which provides protection against water loss and is capable to resist wetting, thus making them a desirable model for biomimetic designs. Their waxy covers enable them to infest mainly leaves of coconut trees despite the harsh wind and rain. This study aims to describe and compare the micro morphological characters on the surfaces of their scale covers consequently, how these micro structures affect their wetting properties. Scanning electron microscope was used for the surface characterization while an optical contact angle meter was employed in the wetting measurement. The scale cover of A. destructor is composed of multiple overlapping layers of wax that is arranged regularly while that of A. rigidus is composed of a uniform layer of wax with much more prominent wax ribbons irregularly arranged compared to the former. The protrusions found on the two organisms are formed by the wax ribbons that differ in arrangement with their height being A. destructor (3.57+1.29) < A. rigidus (4.23+1.22) and their density A. destructor (15+2.94) < A. rigidus (18.33+2.64). These morphological measurements could affect the contact angle (CA θ) measurement of A. destructor (102.66+9.78°) < A. rigidus (102.77 + 11.01°) wherein the assessment that the interaction of the liquid to the microstructures of the substrate is a large factor in the wetting properties of the insect scales is realized. The calculated surface free energy of A. destructor (38.47 mJ/m²) > A. rigidus (31.02 mJ/m²) shows inverse proportionality with the CA measurement. The dispersive interaction between the surface and liquid is more prevalent compared to the polar interaction for both Aspidiotus species, which was observed using the Fowkes method. The results of this study have possible applications to be a potential biomimetic design for various industries such as textiles and coatings.Keywords: Aspidiotus spp., biomimetics, contact angle, surface characterization, wetting behavior
Procedia PDF Downloads 1272842 Ensuring Safe Operation by Providing an End-To-End Field Monitoring and Incident Management Approach for Autonomous Vehicle Based on ML/Dl SW Stack
Authors: Lucas Bublitz, Michael Herdrich
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By achieving the first commercialization approval in San Francisco the Autonomous Driving (AD) industry proves the technology maturity of the SAE L4 AD systems and the corresponding software and hardware stack. This milestone reflects the upcoming phase in the industry, where the focus is now about scaling and supervising larger autonomous vehicle (AV) fleets in different operation areas. This requires an operation framework, which organizes and assigns responsibilities to the relevant AV technology and operation stakeholders from the AV system provider, the Remote Intervention Operator, the MaaS provider and regulatory & approval authority. This holistic operation framework consists of technological, processual, and organizational activities to ensure safe operation for fully automated vehicles. Regarding the supervision of large autonomous vehicle fleets, a major focus is on the continuous field monitoring. The field monitoring approach must reflect the safety and security criticality of incidents in the field during driving operation. This includes an automatic containment approach, with the overall goal to avoid safety critical incidents and reduce downtime by a malfunction of the AD software stack. An End-to-end (E2E) field monitoring approach detects critical faults in the field, uses a knowledge-based approach for evaluating the safety criticality and supports the automatic containment of these E/E faults. Applying such an approach will ensure the scalability of AV fleets, which is determined by the handling of incidents in the field and the continuous regulatory compliance of the technology after enhancing the Operational Design Domain (ODD) or the function scope by Functions on Demand (FoD) over the entire digital product lifecycle.Keywords: field monitoring, incident management, multicompliance management for AI in AD, root cause analysis, database approach
Procedia PDF Downloads 802841 Greenhouse Controlled with Graphical Plotting in Matlab
Authors: Bruno R. A. Oliveira, Italo V. V. Braga, Jonas P. Reges, Luiz P. O. Santos, Sidney C. Duarte, Emilson R. R. Melo, Auzuir R. Alexandria
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This project aims to building a controlled greenhouse, or for better understanding, a structure where one can maintain a given range of temperature values (°C) coming from radiation emitted by an incandescent light, as previously defined, characterizing as a kind of on-off control and a differential, which is the plotting of temperature versus time graphs assisted by MATLAB software via serial communication. That way it is possible to connect the stove with a computer and monitor parameters. In the control, it was performed using a PIC 16F877A microprocessor which enabled convert analog signals to digital, perform serial communication with the IC MAX232 and enable signal transistors. The language used in the PIC's management is Basic. There are also a cooling system realized by two coolers 12V distributed in lateral structure, being used for venting and the other for exhaust air. To find out existing temperature inside is used LM35DZ sensor. Other mechanism used in the greenhouse construction was comprised of a reed switch and a magnet; their function is in recognition of the door position where a signal is sent to a buzzer when the door is open. Beyond it exist LEDs that help to identify the operation which the stove is located. To facilitate human-machine communication is employed an LCD display that tells real-time temperature and other information. The average range of design operating without any major problems, taking into account the limitations of the construction material and structure of electrical current conduction, is approximately 65 to 70 ° C. The project is efficient in these conditions, that is, when you wish to get information from a given material to be tested at temperatures not as high. With the implementation of the greenhouse automation, facilitating the temperature control and the development of a structure that encourages correct environment for the most diverse applications.Keywords: greenhouse, microcontroller, temperature, control, MATLAB
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