Search results for: FE analyses
3338 Rethinking Peace Journalism in Pakistan: A Critical Analysis of News Discourse on the Afghan Refugee Repatriation Conflict
Authors: Ayesha Hasan
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This study offers unique perspectives and analyses of peace and conflict journalism through interpretative repertoire, media frames, and critical discourse analyses. Two major English publications in Pakistan, representing both long and short-form journalism, are investigated to uncover how the Afghan refugee repatriation from Pakistan in 2016-17 has been framed in Pakistani English media. Peace journalism focuses on concepts such as peace initiatives and peace building, finding common ground, and preventing further conflict. This study applies Jake Lynch’s Coding Criteria to guide the critical discourse analysis and Lee and Maslog’s Peace Journalism Quotient to examine the extent of peace journalism in each text. This study finds that peace journalism is missing in Pakistani English press, but represented, to an extent, in long-form print and online coverage. Two new alternative frames are also proposed. This study gives an in-depth understanding of if and how journalists in Pakistan are covering conflicts and framing stories that can be identified as peace journalism. This study represents significant contributions to the remarkably limited scholarship on peace and conflict journalism in Pakistan and extends Shabbir Hussain’s work on critical pragmatic perspectives on peace journalism in Pakistan.Keywords: Afghan refugee repatriation, Critical discourse analysis, Media framing , Peace and conflict journalism
Procedia PDF Downloads 2013337 Static and Dynamic Analysis of Hyperboloidal Helix Having Thin Walled Open and Close Sections
Authors: Merve Ermis, Murat Yılmaz, Nihal Eratlı, Mehmet H. Omurtag
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The static and dynamic analyses of hyperboloidal helix having the closed and the open square box sections are investigated via the mixed finite element formulation based on Timoshenko beam theory. Frenet triad is considered as local coordinate systems for helix geometry. Helix domain is discretized with a two-noded curved element and linear shape functions are used. Each node of the curved element has 12 degrees of freedom, namely, three translations, three rotations, two shear forces, one axial force, two bending moments and one torque. Finite element matrices are derived by using exact nodal values of curvatures and arc length and it is interpolated linearly throughout the element axial length. The torsional moments of inertia for close and open square box sections are obtained by finite element solution of St. Venant torsion formulation. With the proposed method, the torsional rigidity of simply and multiply connected cross-sections can be also calculated in same manner. The influence of the close and the open square box cross-sections on the static and dynamic analyses of hyperboloidal helix is investigated. The benchmark problems are represented for the literature.Keywords: hyperboloidal helix, squared cross section, thin walled cross section, torsional rigidity
Procedia PDF Downloads 3773336 Research of Strong-Column-Weak-Beam Criteria of Reinforced Concrete Frames Subjected to Biaxial Seismic Excitation
Authors: Chong Zhang, Mu-Xuan Tao
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In several earthquakes, numerous reinforced concrete (RC) frames subjected to seismic excitation demonstrated a collapse pattern characterized by column hinges, though designed according to the Strong-Column-Weak-Beam (S-C-W-B) criteria. The effect of biaxial seismic excitation on the disparity between design and actual performance is carefully investigated in this article. First, a modified load contour method is proposed to derive a closed-form equation of biaxial bending moment strength, which is verified by numerical and experimental tests. Afterwards, a group of time history analyses of a simple frame modeled by fiber beam-column elements subjected to biaxial seismic excitation are conducted to verify that the current S-C-W-B criteria are not adequate to prevent the occurrence of column hinges. A biaxial over-strength factor is developed based on the proposed equation, and the reinforcement of columns is appropriately amplified with this factor to prevent the occurrence of column hinges under biaxial excitation, which is proved to be effective by another group of time history analyses.Keywords: biaxial bending moment capacity, biaxial seismic excitation, fiber beam model, load contour method, strong-column-weak-beam
Procedia PDF Downloads 993335 Latitudinal Impact on Spatial and Temporal Variability of 7Be Activity Concentrations in Surface Air along Europe
Authors: M. A. Hernández-Ceballos, M. Marín-Ferrer, G. Cinelli, L. De Felice, T. Tollefsen, E. Nweke, P. V. Tognoli, S. Vanzo, M. De Cort
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This study analyses the latitudinal impact of the spatial and temporal distribution on the cosmogenic isotope 7Be in surface air along Europe. The long-term database of the 6 sampling sites (Ivalo, Helsinki, Berlin, Freiburg, Sevilla and La Laguna), that regularly provide data to the Radioactivity Environmental Monitoring (REM) network managed by the Joint Research Centre (JRC) in Ispra, were used. The selection of the stations was performed attending to different factors, such as 1) heterogeneity in terms of latitude and altitude, and 2) long database coverage. The combination of these two parameters ensures a high degree of representativeness of the results. In the later, the temporal coverage varies between stations, being used in the present study sampling stations with a database more or less continuously from 1984 to 2011. The mean values of 7Be activity concentration presented a spatial distribution value ranging from 2.0 ± 0.9 mBq/m3 (Ivalo, north) to 4.8 ± 1.5 mBq/m3 (La Laguna, south). An increasing gradient with latitude was observed from the north to the south, 0.06 mBq/m3. However, there was no correlation with altitude, since all stations are sited within the atmospheric boundary layer. The analyses of the data indicated a dynamic range of 7Be activity for solar cycle and phase (maximum or minimum), having been observed different impact on stations according to their location. The results indicated a significant seasonal behavior, with the maximum concentrations occurring in the summer and minimum in the winter, although with differences in the values reached and in the month registered. Due to the large heterogeneity in the temporal pattern with which the individual radionuclide analyses were performed in each station, the 7Be monthly index was calculated to normalize the measurements and perform the direct comparison of monthly evolution among stations. Different intensity and evolution of the mean monthly index were observed. The knowledge of the spatial and temporal distribution of this natural radionuclide in the atmosphere is a key parameter for modeling studies of atmospheric processes, which are important phenomena to be taken into account in the case of a nuclear accident.Keywords: Berilium-7, latitudinal impact in Europe, seasonal and monthly variability, solar cycle
Procedia PDF Downloads 3373334 Public Bus Transport Passenger Safety Evaluations in Ghana: A Phenomenological Constructivist Exploration
Authors: Enoch F. Sam, Kris Brijs, Stijn Daniels, Tom Brijs, Geert Wets
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Notwithstanding the growing body of literature that recognises the importance of personal safety to public transport (PT) users, it remains unclear what PT users consider regarding their safety. In this study, we explore the criteria PT users in Ghana use to assess bus safety. This knowledge will afford a better understanding of PT users’ risk perceptions and assessments which may contribute to theoretical models of PT risk perceptions. We utilised phenomenological research methodology, with data drawn from 61 purposively sampled participants. Data collection (through focus group discussions and in-depth interviews) and analyses were done concurrently to the point of saturation. Our inductive data coding and analyses through the constant comparison and content analytic techniques resulted in 4 code categories (conceptual dimensions), 27 codes (safety items/criteria), and 100 quotations (data segments). Of the number of safety criteria participants use to assess bus safety, vehicle condition, driver’s marital status, and transport operator’s safety records were the most considered. With each criterion, participants rightly demonstrated its respective relevance to bus safety. These findings imply that investment in and maintenance of safer vehicles, and responsible and safety-conscious drivers, and prioritization of passengers’ safety are key-targets for public bus/minibus operators in Ghana.Keywords: safety evaluations, public bus/minibus, passengers, phenomenology, Ghana
Procedia PDF Downloads 3373333 The Indebtedness of Men and Women: A Study of Personal Bankruptcies in the Czech Republic
Authors: Zuzana Fišerová, Marie Paseková
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Debt relief (also labelled personal bankruptcy) is a bankruptcy settlement method which was implemented into Czech legislation by the Insolvency Act (Act No. 182/2006 Coll. on Insolvency and its Resolution) on 1 January 2008. The need to implement the institute of personal bankruptcy arose from the excessive over-indebtedness of many inhabitants of the Czech Republic after the crisis that arose around 2008 and 2009. The contribution analyses the development in the manner in which households approach personal bankruptcy and assesses and surveys the differences between indebtedness among men and women. The first section analyses the development in numbers of filed personal bankruptcy petitions and the successfulness thereof; it likewise analyses the impact of other economic influences (regional differences, unemployment etc.). The differences between debtors in dependency to gender are also surveyed. A survey of insolvency proceedings for 664 persons whose insolvency proceedings were commenced in 2008 was conducted, whilst the data were acquired from the publicly accessible insolvency register. The hypothesis on the equality of the average debt level of men and women was tested when comparing indebtedness in dependency to debtor gender. At a significance level of 0.05, the test confirmed that the mean value of debt level for women is lower than the mean value of debt level for men. Through analysis of further results, it was found that the average level of debt among women was CZK 537 thousand, while the average level of creditor satisfaction reached 46.2%. Men in the monitored sample had an average level of reported receivables of CZK 652 thousand, satisfaction of their creditors reached 58.8%. The main changes in the institute of personal bankruptcy are then evaluated in the closing discussion, and the impacts of these changes for households are assessed. The development of legislation in the Czech Republic and practice are shifting towards broader usage of personal bankruptcy, especially insofar as it can now also be used by entrepreneurs. Furthermore, the amendment of the Insolvency Act has enabled married couples to apply for joint debt relief, which has improved the position of the marriage partner with lower income and who would not get permission for debt relief on his/her own (mostly women are at issue). In current practice, the condition of adequate income is also solved by the fact that another person (usually a family member) undertakes to donate a certain monthly sum throughout the duration of the debt relief. Personal bankruptcy can thus be completed also by individuals to whom it would previously have been denied by the court.Keywords: debtor, households, insolvency act, over-indebtedness, personal bankruptcy
Procedia PDF Downloads 2843332 A Demonstration of How to Employ and Interpret Binary IRT Models Using the New IRT Procedure in SAS 9.4
Authors: Ryan A. Black, Stacey A. McCaffrey
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Over the past few decades, great strides have been made towards improving the science in the measurement of psychological constructs. Item Response Theory (IRT) has been the foundation upon which statistical models have been derived to increase both precision and accuracy in psychological measurement. These models are now being used widely to develop and refine tests intended to measure an individual's level of academic achievement, aptitude, and intelligence. Recently, the field of clinical psychology has adopted IRT models to measure psychopathological phenomena such as depression, anxiety, and addiction. Because advances in IRT measurement models are being made so rapidly across various fields, it has become quite challenging for psychologists and other behavioral scientists to keep abreast of the most recent developments, much less learn how to employ and decide which models are the most appropriate to use in their line of work. In the same vein, IRT measurement models vary greatly in complexity in several interrelated ways including but not limited to the number of item-specific parameters estimated in a given model, the function which links the expected response and the predictor, response option formats, as well as dimensionality. As a result, inferior methods (a.k.a. Classical Test Theory methods) continue to be employed in efforts to measure psychological constructs, despite evidence showing that IRT methods yield more precise and accurate measurement. To increase the use of IRT methods, this study endeavors to provide a comprehensive overview of binary IRT models; that is, measurement models employed on test data consisting of binary response options (e.g., correct/incorrect, true/false, agree/disagree). Specifically, this study will cover the most basic binary IRT model, known as the 1-parameter logistic (1-PL) model dating back to over 50 years ago, up until the most recent complex, 4-parameter logistic (4-PL) model. Binary IRT models will be defined mathematically and the interpretation of each parameter will be provided. Next, all four binary IRT models will be employed on two sets of data: 1. Simulated data of N=500,000 subjects who responded to four dichotomous items and 2. A pilot analysis of real-world data collected from a sample of approximately 770 subjects who responded to four self-report dichotomous items pertaining to emotional consequences to alcohol use. Real-world data were based on responses collected on items administered to subjects as part of a scale-development study (NIDA Grant No. R44 DA023322). IRT analyses conducted on both the simulated data and analyses of real-world pilot will provide a clear demonstration of how to construct, evaluate, and compare binary IRT measurement models. All analyses will be performed using the new IRT procedure in SAS 9.4. SAS code to generate simulated data and analyses will be available upon request to allow for replication of results.Keywords: instrument development, item response theory, latent trait theory, psychometrics
Procedia PDF Downloads 3563331 Physico-Chemical and Antibacterial Properties of Neem Extracts
Authors: C. C. Igwe
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Several parts of Neem tree (Azadirachta indica) are used in traditional medicine in many West African countries for the treatment of various human diseases. The leaf, stem - bark and seed were air dried for 8, 5 and 7 days, respectively. The shells were carfully separated from the seeds, each powdered sample obtained with mechanical miller and 250 mm sieve. The neem samples were individually subjected to extraction with acetone, n-hexane for 48hr and 72 hr, respectively. Physico-chemical and antibacterial evaluation were carried out using standard methods. Results of physico - chemical analyses of the extracted oil from the seed shows that it has a brownish colour, with a smell similar to garlic while the moisture content, refractive index are 0.76% and 1.47 respectively. Other vital chemical results obtained from the neem oil such as saponification value (234.62), acid value (10.84 %), free fatty acid (5.84 %) and peroxide value (10.52%) indicated the oil extracted satisfied standard oils parameters for quality soap and cosmetics production. The antibacterial screening by disc diffusion revealed the oil demonstrated high activity against Staphylococcus aureus. Both the physio-chemical and antibacterial of samples have been certified by National Agency for Food and Drugs Administration and Control. The preliminary results of this study may validate the medicinal value of the plant. Further studies are in progress to clarify the in vivo potentials of neem extracts in the management of human communicable diseases and this is a subject of investigation in our group.Keywords: anti-bacterial, neem extract, physico-chemical analyses, staphylococcus aureus
Procedia PDF Downloads 743330 Production of Pig Iron by Smelting of Blended Pre-Reduced Titaniferous Magnetite Ore and Hematite Ore Using Lean Grade Coal
Authors: Bitan Kumar Sarkar, Akashdeep Agarwal, Rajib Dey, Gopes Chandra Das
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The rapid depletion of high-grade iron ore (Fe2O3) has gained attention on the use of other sources of iron ore. Titaniferous magnetite ore (TMO) is a special type of magnetite ore having high titania content (23.23% TiO2 present in this case). Due to high TiO2 content and high density, TMO cannot be treated by the conventional smelting reduction. In this present work, the TMO has been collected from high-grade metamorphic terrain of the Precambrian Chotanagpur gneissic complex situated in the eastern part of India (Shaltora area, Bankura district, West Bengal) and the hematite ore has been collected from Visakhapatnam Steel Plant (VSP), Visakhapatnam. At VSP, iron ore is received from Bailadila mines, Chattisgarh of M/s. National Mineral Development Corporation. The preliminary characterization of TMO and hematite ore (HMO) has been investigated by WDXRF, XRD and FESEM analyses. Similarly, good quality of coal (mainly coking coal) is also getting depleted fast. The basic purpose of this work is to find how lean grade coal can be utilised along with TMO for smelting to produce pig iron. Lean grade coal has been characterised by using TG/DTA, proximate and ultimate analyses. The boiler grade coal has been found to contain 28.08% of fixed carbon and 28.31% of volatile matter. TMO fines (below 75 μm) and HMO fines (below 75 μm) have been separately agglomerated with lean grade coal fines (below 75 μm) in the form of briquettes using binders like bentonite and molasses. These green briquettes are dried first in oven at 423 K for 30 min and then reduced isothermally in tube furnace over the temperature range of 1323 K, 1373 K and 1423 K for 30 min & 60 min. After reduction, the reduced briquettes are characterized by XRD and FESEM analyses. The best reduced TMO and HMO samples are taken and blended in three different weight percentage ratios of 1:4, 1:8 and 1:12 of TMO:HMO. The chemical analysis of three blended samples is carried out and degree of metallisation of iron is found to contain 89.38%, 92.12% and 93.12%, respectively. These three blended samples are briquetted using binder like bentonite and lime. Thereafter these blended briquettes are separately smelted in raising hearth furnace at 1773 K for 30 min. The pig iron formed is characterized using XRD, microscopic analysis. It can be concluded that 90% yield of pig iron can be achieved when the blend ratio of TMO:HMO is 1:4.5. This means for 90% yield, the maximum TMO that could be used in the blend is about 18%.Keywords: briquetting reduction, lean grade coal, smelting reduction, TMO
Procedia PDF Downloads 3193329 Determining Factors of Suspended Glass Systems with Pre-Stress Cable Truss
Authors: Cemil Atakara, Hüseyin Eryaman
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The use of glass as an envelope of a building has been increasing in the twentieth century. For more transparency and dematerialization new glass facade types have emerged in the past two decades which depends on point fixed glazing system (PFGS). The aim of this study is to analyze of the PFGS systems which are used on the glass curtain wall according to their types, degree, architectural and structural effects. This new system is desired because it enhances the transparency of the façade and it minimizes the component of the frames or of the profiles. This PFGS led to new structural elements which use cables, rods, trusses when designing a glass building facades, this structural element called the suspended glass system with pre-stressed cable truss (SGSPCT) which has been used for the first time in 1980 in Serres building. The twenty glass buildings which are designed in different systems have been analyzed during this study. After these analyses five selected SGSPCT building analyzed deeply and one skeletal frame building selected from Lefkosa redesigned according to the analysis results. These selected buildings have been included of various cable-truss system typologies and degree. The methodology of this study is building analysis method and literature survey with the help of books, articles, magazines, drawings, internet sources and applied connection details of the glass buildings. The selected five glass buildings and case building have been detailed analyzed with their architectural drawings, photographs and details. A gridshell structure can be compared with a shell structure; it consists of discrete members connecting nodal points. As these nodal points lie on the surface of an imaginary shell, their shapes function almost identically. Difference between shell and gridshell structures can be found in the fact that, due to their free-form and thus, due to the presence of bending forces, gridshells are required to resist loading through their cross-section. This research is divided into parts. A general study about the glass building and cable-glass and grid shell system will be done in the first chapters. Structural analyses and detailed analyses with schematic drawings with the plans, sections of the selected buildings will be explained in the second part. The third part it consists of the advantages and disadvantages of the use of the SGSPCT and Grid Shell in architecture. The study consists of four chapters including the introduction chapter. The general information of the SGSPCT and glazing system has been mentioned in the first chapter. Structural features, typologies, transparency principle and analytical information on systems have been explained of the selected buildings in the second chapter. The detailed analyses of case building have been done according to their schematic drawings with the plans, sections in the third chapter. After third chapter SGSPCT discussed on to the case building and selected buildings. SGSPCT systems have been compared with their advantages and disadvantages to the other systems. Advantages of cable-truss systems and SGSPCT have been concluded that the use of glass substrates in the last chapter.Keywords: cable truss, glass, grid shell, transparency
Procedia PDF Downloads 4113328 The Influence of Interior Decoration on Customer's Perception of Hotels in Uyo, Akwa Ibom State Nigeria
Authors: O. B. Enemuo, A. A. Onubuogu
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This work evaluated the influence of interior of decoration on customer perception of hotels in Uyo Akwa Ibom State. Specifically the study identified the various interior decoration used in hotels in the study area, determined the interior decoration used in hotels that appeal to the customer more, ascertained the influence of interior decoration on the level of patronage in the hotel in the study area and suggested ways of improving the interior decoration of hotels in the study area for sustainability. The study was guided by four research questions and two hypotheses. It adopted survey research design; structured questionnaire was used for data collection. The samples for the study were four hundred (400) staff and managers from the various hotels in the study area. Data generated were analyzed using mean and standard deviation analyses of variance (ANOVA) derived from regression analyses to test the hypotheses. The result of the finding showed that satisfactory interior decoration has a positive influence on the sustainability of the hospitality establishments in Uyo. The hypothesis showed that there was a significant relationship between the gender perception on the influence of interior decoration in the hotel and significant relationship between the gender perceptions on the influence of interior decoration in the hotels. From the finding, it was recommended that the hotels should design interior decorative service delivery system which has an impact on customer satisfaction in the hospitality industry and practiced healthy decorative environment and increased customer satisfaction.Keywords: influence, interior decoration, customer’s perception, hotels
Procedia PDF Downloads 2943327 The Contact Behaviors of Seals Under Combined Normal and Tangential Loading: A Multiscale Finite Element Contact Analysis
Authors: Runliang Wang, Jianhua Liu, Duo Jia, Xiaoyu Ding
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The contact between sealing surfaces plays a vital role in guaranteeing the sealing performance of various seals. To date, analyses of sealing structures have rarely considered both structural parameters (macroscale) and surface roughness information (microscale) of sealing surfaces due to the complex modeling process. Meanwhile, most of the contact analyses applied to seals were conducted only under normal loading, which still existssome distance from real loading conditions in engineering. In this paper, a multiscale rough contact model, which took both macrostructural parameters of seals and surface roughness information of sealing surfaces into consideration for the cone-cone seal, was established. By using the finite element method (FEM), the combined normal and tangential loading was applied to the model to simulate the assembly process of the cone-cone seal. The evolution of the contact behaviors during the assembly process, such as the real contact area (RCA), the distribution of contact pressure, and contact status, are studied in detail. The results showed the non-linear relationship between the RCA and the load, which was different from the normal loading cases. In addition, the evolution of the real contact area of cone-cone seals with isotropic and anisotropic rough surfaces are also compared quantitatively.Keywords: contact mechanics, FEM, randomly rough surface, real contact area, sealing
Procedia PDF Downloads 1833326 Migration Management in the Eastern Mediterranean: The European Union's Legacy of the Securitization and Lacking on the Principle of Solidarity and Burden Sharing
Authors: Tasawar Ashraf
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The paper argues that the European Union’s securitized recourse to migration management which is lacking on the principle of solidarity has enhanced the sufferings of the asylum seekers by influencing the asylum policies of the non-EU states in the Eastern Mediterranean. The research critically analyses the development of the Turkish Asylum Policy and advocates that due to extraordinary burden of refugees and conceivable chances of getting EU membership, Turkey is developing its asylum policy essentially on the footprints of the EU. Such political and economic domination of the EU are resulting in the development of broader securitized migration zone in the EU and MENA region. Therefore, this paper critically analyses two interconnected issues, i.e., securitization of the migration in the EU and MENA region and the deficiency of the principle of solidarity and burden sharing in the European Agenda on Migration and how it reflects on Turkish asylum policy. This paper suggests that the EU must adopt a more generous resettle scheme ensuring the division of the refugee burden on all member and regional states by considering different political, social, and economic factors. Only such corporation can increase the pool of refugee hosting states by collaborating with the regional states to develop their asylum systems in accordance with international law.Keywords: European Agenda on Migration (EAM), EU, Middle East and North Africa (MENA), Treaty on the Functioning of the European Union (TFEU)
Procedia PDF Downloads 1783325 Fabrication and Characterization of Al2O3 Based Electrical Insulation Coatings Around SiC Fibers
Authors: S. Palaniyappan, P. K. Chennam, M. Trautmann, H. Ahmad, T. Mehner, T. Lampke, G. Wagner
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In structural-health monitoring of fiber reinforced plastics (FRPs), every single inorganic fiber sensor that are integrated into the bulk material requires an electrical insulation around itself, when the surrounding reinforcing fibers are electrically conductive. This results in a more accurate data acquisition only from the sensor fiber without any electrical interventions. For this purpose, thin nano-films of aluminium oxide (Al2O3)-based electrical-insulation coatings have been fabricated around the Silicon Carbide (SiC) single fiber sensors through reactive DC magnetron sputtering technique. The sputtered coatings were amorphous in nature and the thickness of the coatings increased with an increase in the sputter time. Microstructural characterization of the coated fibers performed using scanning electron microscopy (SEM) confirmed a homogeneous circumferential coating with no detectable defects or cracks on the surface. X-ray diffraction (XRD) analyses of the as-sputtered and 2 hours annealed coatings (825 & 1125 ˚C) revealed the amorphous and crystalline phases of Al2O3 respectively. Raman spectroscopic analyses produced no characteristic bands of Al2O3, as the thickness of the films was in the nanometer (nm) range, which is too small to overcome the actual penetration depth of the laser used. In addition, the influence of the insulation coatings on the mechanical properties of the SiC sensor fibers has been analyzed.Keywords: Al₂O₃ thin film, electrical insulation coating, PVD process, SiC fibre, single fibre tensile test
Procedia PDF Downloads 1233324 Optimization of End Milling Process Parameters for Minimization of Surface Roughness of AISI D2 Steel
Authors: Pankaj Chandna, Dinesh Kumar
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The present work analyses different parameters of end milling to minimize the surface roughness for AISI D2 steel. D2 Steel is generally used for stamping or forming dies, punches, forming rolls, knives, slitters, shear blades, tools, scrap choppers, tyre shredders etc. Surface roughness is one of the main indices that determines the quality of machined products and is influenced by various cutting parameters. In machining operations, achieving desired surface quality by optimization of machining parameters, is a challenging job. In case of mating components the surface roughness become more essential and is influenced by the cutting parameters, because, these quality structures are highly correlated and are expected to be influenced directly or indirectly by the direct effect of process parameters or their interactive effects (i.e. on process environment). In this work, the effects of selected process parameters on surface roughness and subsequent setting of parameters with the levels have been accomplished by Taguchi’s parameter design approach. The experiments have been performed as per the combination of levels of different process parameters suggested by L9 orthogonal array. Experimental investigation of the end milling of AISI D2 steel with carbide tool by varying feed, speed and depth of cut and the surface roughness has been measured using surface roughness tester. Analyses of variance have been performed for mean and signal-to-noise ratio to estimate the contribution of the different process parameters on the process.Keywords: D2 steel, orthogonal array, optimization, surface roughness, Taguchi methodology
Procedia PDF Downloads 5443323 Lipidomic Profiling of Chlorella sp. and Scenedesmus abundans towards Deciphering Phospholipids and Glycolipids under Nitrogen Limited Condition
Authors: J. Singh, Swati Dubey, R. P. Singh
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Microalgal strains can accumulate greatly enhanced levels of lipids under nitrogen-deficient condition, making these as one of the most promising sustainable sources for biofuel production. High-grade biofuel production from microalgal biomass could be facilitated by analysing the lipid content of the microalgae and enumerating its dynamics under varying nutrient conditions. In the present study, a detailed investigation of changes in lipid composition in Chlorella species and Scenedesmus abundans in response to nitrogen limited condition was performed to provide novel mechanistic insights into the lipidome during stress conditions. The mass spectroscopic approaches mainly LC-MS and GC-MS were employed for lipidomic profiling in both the microalgal strains. The analyses of lipid profiling using LC-MS revealed distinct forms of lipids mainly phospho- and glycolipids, including betaine lipids, and various other forms of lipids in both the microalgal strains. As detected, an overall decrease in polar lipids was observed. However, GC-MS analyses had revealed that the synthesis of the storage lipid i.e. triacylglycerol (TAG) was substantially stimulated in both the strains under nitrogen limited conditions. The changes observed in the overall fatty acid profile were primarily due to the decrease in proportion of polar lipids to TAGs. This study had enabled in analysing a detailed and orchestrated form of lipidomes in two different microalgal strains having potential for biodiesel production.Keywords: biofuel, GC-MS, LC-MS, lipid, microalgae
Procedia PDF Downloads 3703322 Program Level Learning Outcomes in Music and Technology: Toward Improved Assessment and Better Communication
Authors: Susan Lewis
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The assessment of learning outcomes at the program level has attracted much international interest from the perspectives of quality assurance and ongoing curricular redesign and renewal. This paper examines program-level learning outcomes in the field of music and technology, an area of study that has seen an explosion in program development over the past fifteen years. The Audio Engineering Society (AES) maintains an online directory of educational institutions worldwide, yielding the most comprehensive inventory of programs and courses in music and technology. The inventory includes courses, programs, and degrees in music and technology, music and computer science, music production, and the music industry. This paper focuses on published student learning outcomes for undergraduate degrees in music and technology and analyses commonalities at institutions in North America, the United Kingdom, and Europe. The results of a survey of student learning outcomes at twenty institutions indicates a focus on three distinct student learning outcomes: (1) cross-disciplinary knowledge in the fields of music and technology; (2) the practical application of training through the professional industry; and (3) the acquisition of skills in communication and collaboration. The paper then analyses assessment mechanisms for tracking student learning and achievement of learning outcomes at these institutions. The results indicate highly variable assessment practices. Conclusions offer recommendations for enhancing assessment techniques and better communicating learning outcomes to students.Keywords: quality assurance, student learning; learning outcomes, music and technology
Procedia PDF Downloads 1853321 Investigating Jacket-Type Offshore Structures Failure Probability by Applying the Reliability Analyses Methods
Authors: Majid Samiee Zonoozian
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For such important constructions as jacket type platforms, scrupulous attention in analysis, design and calculation processes is needed. The reliability assessment method has been established into an extensively used method to behavior safety calculation of jacket platforms. In the present study, a methodology for the reliability calculation of an offshore jacket platform in contradiction of the extreme wave loading state is available. Therefore, sensitivity analyses are applied to acquire the nonlinear response of jacket-type platforms against extreme waves. The jacket structure is modeled by applying a nonlinear finite-element model with regards to the tubular members' behave. The probability of a member’s failure under extreme wave loading is figured by a finite-element reliability code. The FORM and SORM approaches are applied for the calculation of safety directories and reliability indexes have been detected. A case study for a fixed jacket-type structure positioned in the Persian Gulf is studied by means of the planned method. Furthermore, to define the failure standards, equations suggested by the 21st version of the API RP 2A-WSD for The jacket-type structures’ tubular members designing by applying the mixed axial bending and axial pressure. Consequently, the effect of wave Loades in the reliability index was considered.Keywords: Jacket-Type structure, reliability, failure probability, tubular members
Procedia PDF Downloads 1723320 Physician and Theologian: An Analysis of Ibn Rabban’s Approach on Sīra Nabawiyya
Authors: Ahmad Sanusi Azmi, Amiruddin Mohd Sobali, Zulhilmi Mohamed Nor, Mohd Yusuf Ismail, Amran Abdul Halim
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The non-Muslim communities’ reactions to the denials of the prophethood of Muḥammad in the ninth century created an impact on the development of Islamic prophetology. Vigorous refutations from non-Muslim community, specifically the Jews, Christians and Brahmins urged Muslims to develop a solid mechanism in defense of the status of their beloved prophet. One of the works that has been recognized as an apparatus to defend the Prophet Muḥammad veracity is al-Dīn wa al-Dawla composed by Ibn Rabban, a physician of the Caliph’s court. This study analyses the novelty of his approaches in exploring Sīra Nabawiyya and defending the prophethood of Muḥammad. The study employed a descriptive, comparative and critical approach where it analyses and extracts the author original approach in explaining the legitimacy of Muḥammad’s prophethood and enlightening the Prophet’s biography. The study in its finding argues that most of Ibn Rabban arguments in this work are actually developed from the foundations of Biblical scripture. His style of interpreting Biblical passages indicates a possible dependence on Ibn al-Layth’s letter. However, the way in which he presents Qur’ānic references seems not to be in accordance with Ibn al-Layth’s perspective. This is where the novelty of his approach is distinguished. As a result, the study also affirms that Ibn Rabban imposes his own standards of selection and interpretation of Qur’ānic verses when he applies it as reference to the Prophet life.Keywords: Sīra Nabawiyya, Ibn Rabban, al-Dīn wa al-Dawla, Christian, Dalāil Nubuwwa
Procedia PDF Downloads 3323319 The Influence of Shear Wall Position on Seismic Performance in Buildings
Authors: Akram Khelaifia, Nesreddine Djafar Henni
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Reinforced concrete shear walls are essential components in protecting buildings from seismic forces by providing both strength and stiffness. This study focuses on optimizing the placement of shear walls in a high seismic zone. Through nonlinear analyses conducted on an eight-story building, various scenarios of shear wall positions are investigated to evaluate their impact on seismic performance. Employing a performance-based seismic design (PBSD) approach, the study aims to meet acceptance criteria related to inter-story drift ratio and damage levels. The findings emphasize the importance of concentrating shear walls in the central area of the building during the design phase. This strategic placement proves more effective compared to peripheral distributions, resulting in reduced inter-story drift and mitigated potential damage during seismic events. Additionally, the research explores the use of shear walls that completely infill the frame, forming compound shapes like Box configurations. It is discovered that incorporating such complete shear walls significantly enhances the structure's reliability concerning inter-story drift. Conversely, the absence of complete shear walls within the frame leads to reduced stiffness and the potential deterioration of short beams.Keywords: performance level, pushover analysis, shear wall, plastic hinge, nonlinear analyses
Procedia PDF Downloads 533318 Microscopic Simulation of Toll Plaza Safety and Operations
Authors: Bekir O. Bartin, Kaan Ozbay, Sandeep Mudigonda, Hong Yang
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The use of microscopic traffic simulation in evaluating the operational and safety conditions at toll plazas is demonstrated. Two toll plazas in New Jersey are selected as case studies and were developed and validated in Paramics traffic simulation software. In order to simulate drivers’ lane selection behavior in Paramics, a utility-based lane selection approach is implemented in Paramics Application Programming Interface (API). For each vehicle approaching the toll plaza, a utility value is assigned to each toll lane by taking into account the factors that are likely to impact drivers’ lane selection behavior, such as approach lane, exit lane and queue lengths. The results demonstrate that similar operational conditions, such as lane-by-lane toll plaza traffic volume can be attained using this approach. In addition, assessment of safety at toll plazas is conducted via a surrogate safety measure. In particular, the crash index (CI), an improved surrogate measure of time-to-collision (TTC), which reflects the severity of a crash is used in the simulation analyses. The results indicate that the spatial and temporal frequency of observed crashes can be simulated using the proposed methodology. Further analyses can be conducted to evaluate and compare various different operational decisions and safety measures using microscopic simulation models.Keywords: microscopic simulation, toll plaza, surrogate safety, application programming interface
Procedia PDF Downloads 1833317 An Efficient Propensity Score Method for Causal Analysis With Application to Case-Control Study in Breast Cancer Research
Authors: Ms Azam Najafkouchak, David Todem, Dorothy Pathak, Pramod Pathak, Joseph Gardiner
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Propensity score (PS) methods have recently become the standard analysis as a tool for the causal inference in the observational studies where exposure is not randomly assigned, thus, confounding can impact the estimation of treatment effect on the outcome. For the binary outcome, the effect of treatment on the outcome can be estimated by odds ratios, relative risks, and risk differences. However, using the different PS methods may give you a different estimation of the treatment effect on the outcome. Several methods of PS analyses have been used mainly, include matching, inverse probability of weighting, stratification, and covariate adjusted on PS. Due to the dangers of discretizing continuous variables (exposure, covariates), the focus of this paper will be on how the variation in cut-points or boundaries will affect the average treatment effect (ATE) utilizing the stratification of PS method. Therefore, we are trying to avoid choosing arbitrary cut-points, instead, we continuously discretize the PS and accumulate information across all cut-points for inferences. We will use Monte Carlo simulation to evaluate ATE, focusing on two PS methods, stratification and covariate adjusted on PS. We will then show how this can be observed based on the analyses of the data from a case-control study of breast cancer, the Polish Women’s Health Study.Keywords: average treatment effect, propensity score, stratification, covariate adjusted, monte Calro estimation, breast cancer, case_control study
Procedia PDF Downloads 1053316 Development and Validation of Sense of Humor Questionnaire in China
Authors: Yunshi Peng, Shanshan Gao, Sang Qin
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The sense of humor is an integration of cognition, emotion and behavioral tendencies in the process of expressing humor. Previous studies evidenced the positive impact of sense of humor on promoting mental health. However, very few studies investigated this with Chinese populations. The absence of a validated questionnaire limits empirical research on sense of humor in China. This study aimed to develop a Chinese instrument to examine the sense of humor among college students in China. A pool of 72 items was developed by conducting a series of qualitative methods including open-ended questionnaire, individual interviews and literature analysis, followed by an expert rating. A total of 500 college students were recruited from 7 provinces in China to complete all 72 items. The factor structure of sense of humor was established and 25 items were eventually formed by utilizing the exploratory factor analyses (EFA). The questionnaire composed 4 subscales: humor comprehension, humor creativity, attitudes towards humor and optimism level. Confirmatory factor analyses (CFA) from a follow-up study with a different sample of 1200 colleges students showed good model fit. All subscales and the overall questionnaire display satisfying internal consistency. Correlations with criterion variables demonstrated good convergent and discriminant validity. The sense of humor questionnaire is a psychometrically-sound instrument for the population of college students in China. This is applicable for future studies to identify the structure of sense of humor and evaluate the levels of humor for individuals.Keywords: college students, EFA and CFA, questionnaire, sense of humor
Procedia PDF Downloads 3443315 Ice Load Measurements on Known Structures Using Image Processing Methods
Authors: Azam Fazelpour, Saeed R. Dehghani, Vlastimil Masek, Yuri S. Muzychka
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This study employs a method based on image analyses and structure information to detect accumulated ice on known structures. The icing of marine vessels and offshore structures causes significant reductions in their efficiency and creates unsafe working conditions. Image processing methods are used to measure ice loads automatically. Most image processing methods are developed based on captured image analyses. In this method, ice loads on structures are calculated by defining structure coordinates and processing captured images. A pyramidal structure is designed with nine cylindrical bars as the known structure of experimental setup. Unsymmetrical ice accumulated on the structure in a cold room represents the actual case of experiments. Camera intrinsic and extrinsic parameters are used to define structure coordinates in the image coordinate system according to the camera location and angle. The thresholding method is applied to capture images and detect iced structures in a binary image. The ice thickness of each element is calculated by combining the information from the binary image and the structure coordinate. Averaging ice diameters from different camera views obtains ice thicknesses of structure elements. Comparison between ice load measurements using this method and the actual ice loads shows positive correlations with an acceptable range of error. The method can be applied to complex structures defining structure and camera coordinates.Keywords: camera calibration, ice detection, ice load measurements, image processing
Procedia PDF Downloads 3683314 Assessing Influence of End-Boundary Conditions on Stability and Second-Order Lateral Stiffness of Beam-Column Elements Embedded in Non-Homogeneous Soil
Authors: Carlos A. Vega-Posada, Jeisson Alejandro Higuita-Villa, Julio C. Saldarriaga-Molina
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This paper presents a simplified analytical approach to conduct elastic stability and second-order lateral stiffness analyses of beam-column elements (i.e., piles) with generalized end-boundary conditions embedded on a homogeneous or non-homogeneous Pasternak foundation. The solution is derived using the well-known Differential Transformation Method (DTM), and it consists simply of solving a system of two linear algebraic equations. Using other conventional approaches to solve the governing differential equation of the proposed element can be cumbersome and the solution challenging to implement, especially when the non-homogeneity of the soil is considered. The proposed formulation includes the effects of i) any rotational or lateral transverse spring at the ends of the pile, ii) any external transverse load acting along the pile, iii) soil non-homogeneity, and iv) the second-parameter of the elastic foundation (i.e., shear layer connecting the springs at the top). A parametric study is conducted to investigate the effects of different modulus of subgrade reactions, degrees of non-homogeneities, and intermediate end-boundary conditions on the pile response. The same set of equations can be used to conduct both elastic stability and static analyses. Comprehensive examples are presented to show the simplicity and practicability of the proposed method.Keywords: elastic stability, second-order lateral stiffness, soil-non-homogeneity, pile analysis
Procedia PDF Downloads 2093313 Moving beyond the Gender Pay Gap: An Investigation of Pension Gender Inequalities across European Counties
Authors: Enva Doda
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Recent statistical analyses within the European Union (EU) underscore the enduring significance of the Gender Pay Gap in amplifying the Gender Pension Gap, a phenomenon resisting proportional reduction over time. This study meticulously calculates the Pension Gap, scrutinizing contributing variables within diverse pension systems. Furthermore, it investigates whether the "unexplained" segment of the Gender Gap correlates with political institutions, economic systems, historical events, or discrimination, utilizing quantitative methods and the Blinder-Oaxaca Decomposition Method to pinpoint potential discriminatory factors. The descriptive analysis reveals a conspicuous Gender Pension Gap across European nations, displaying notable variation. While an overall reduction in the Gender Gap is observed, the degree of improvement varies among countries. Subsequent analyses will delve into the specific reasons or variables influencing distinct Gender Gap percentages, forming the basis for nuanced policy recommendations. This comprehensive research enriches the ongoing discourse on gender equality and economic equity. By focusing on the root causes of the Pension Gap, the study has the potential to instigate policy adjustments, urging policymakers to reassess systemic structures and contribute to informed decision-making. Emphasizing gender equality as essential for a flourishing and resilient economy, the research aspires to drive positive change on academic and policy fronts.Keywords: blinder Oaxaca decomposition method, discrimination, gender pension gap, quantitative methods, unexplained gender gap
Procedia PDF Downloads 423312 Gene Expression Meta-Analysis of Potential Shared and Unique Pathways Between Autoimmune Diseases Under anti-TNFα Therapy
Authors: Charalabos Antonatos, Mariza Panoutsopoulou, Georgios K. Georgakilas, Evangelos Evangelou, Yiannis Vasilopoulos
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The extended tissue damage and severe clinical outcomes of autoimmune diseases, accompanied by the high annual costs to the overall health care system, highlight the need for an efficient therapy. Increasing knowledge over the pathophysiology of specific chronic inflammatory diseases, namely Psoriasis (PsO), Inflammatory Bowel Diseases (IBD) consisting of Crohn’s disease (CD) and Ulcerative colitis (UC), and Rheumatoid Arthritis (RA), has provided insights into the underlying mechanisms that lead to the maintenance of the inflammation, such as Tumor Necrosis Factor alpha (TNF-α). Hence, the anti-TNFα biological agents pose as an ideal therapeutic approach. Despite the efficacy of anti-TNFα agents, several clinical trials have shown that 20-40% of patients do not respond to treatment. Nowadays, high-throughput technologies have been recruited in order to elucidate the complex interactions in multifactorial phenotypes, with the most ubiquitous ones referring to transcriptome quantification analyses. In this context, a random effects meta-analysis of available gene expression cDNA microarray datasets was performed between responders and non-responders to anti-TNFα therapy in patients with IBD, PsO, and RA. Publicly available datasets were systematically searched from inception to 10th of November 2020 and selected for further analysis if they assessed the response to anti-TNFα therapy with clinical score indexes from inflamed biopsies. Specifically, 4 IBD (79 responders/72 non-responders), 3 PsO (40 responders/11 non-responders) and 2 RA (16 responders/6 non-responders) datasetswere selected. After the separate pre-processing of each dataset, 4 separate meta-analyses were conducted; three disease-specific and a single combined meta-analysis on the disease-specific results. The MetaVolcano R package (v.1.8.0) was utilized for a random-effects meta-analysis through theRestricted Maximum Likelihood (RELM) method. The top 1% of the most consistently perturbed genes in the included datasets was highlighted through the TopConfects approach while maintaining a 5% False Discovery Rate (FDR). Genes were considered as Differentialy Expressed (DEGs) as those with P ≤ 0.05, |log2(FC)| ≥ log2(1.25) and perturbed in at least 75% of the included datasets. Over-representation analysis was performed using Gene Ontology and Reactome Pathways for both up- and down-regulated genes in all 4 performed meta-analyses. Protein-Protein interaction networks were also incorporated in the subsequentanalyses with STRING v11.5 and Cytoscape v3.9. Disease-specific meta-analyses detected multiple distinct pro-inflammatory and immune-related down-regulated genes for each disease, such asNFKBIA, IL36, and IRAK1, respectively. Pathway analyses revealed unique and shared pathways between each disease, such as Neutrophil Degranulation and Signaling by Interleukins. The combined meta-analysis unveiled 436 DEGs, 86 out of which were up- and 350 down-regulated, confirming the aforementioned shared pathways and genes, as well as uncovering genes that participate in anti-inflammatory pathways, namely IL-10 signaling. The identification of key biological pathways and regulatory elements is imperative for the accurate prediction of the patient’s response to biological drugs. Meta-analysis of such gene expression data could aid the challenging approach to unravel the complex interactions implicated in the response to anti-TNFα therapy in patients with PsO, IBD, and RA, as well as distinguish gene clusters and pathways that are altered through this heterogeneous phenotype.Keywords: anti-TNFα, autoimmune, meta-analysis, microarrays
Procedia PDF Downloads 1813311 Factors Affecting Cesarean Section among Women in Qatar Using Multiple Indicator Cluster Survey Database
Authors: Sahar Elsaleh, Ghada Farhat, Shaikha Al-Derham, Fasih Alam
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Background: Cesarean section (CS) delivery is one of the major concerns both in developing and developed countries. The rate of CS deliveries are on the rise globally, and especially in Qatar. Many socio-economic, demographic, clinical and institutional factors play an important role for cesarean sections. This study aims to investigate factors affecting the prevalence of CS among women in Qatar using the UNICEF’s Multiple Indicator Cluster Survey (MICS) 2012 database. Methods: The study has focused on the women’s questionnaire of the MICS, which was successfully distributed to 5699 participants. Following study inclusion and exclusion criteria, a final sample of 761 women aged 19- 49 years who had at least one delivery of giving birth in their lifetime before the survey were included. A number of socio-economic, demographic, clinical and institutional factors, identified through literature review and available in the data, were considered for the analyses. Bivariate and multivariate logistic regression models, along with a multi-level modeling to investigate clustering effect, were undertaken to identify the factors that affect CS prevalence in Qatar. Results: From the bivariate analyses the study has shown that, a number of categorical factors are statistically significantly associated with the dependent variable (CS). When identifying the factors from a multivariate logistic regression, the study found that only three categorical factors -‘age of women’, ‘place at delivery’ and ‘baby weight’ appeared to be significantly affecting the CS among women in Qatar. Although the MICS dataset is based on a cluster survey, an exploratory multi-level analysis did not show any clustering effect, i.e. no significant variation in results at higher level (households), suggesting that all analyses at lower level (individual respondent) are valid without any significant bias in results. Conclusion: The study found a statistically significant association between the dependent variable (CS delivery) and age of women, frequency of TV watching, assistance at birth and place of birth. These results need to be interpreted cautiously; however, it can be used as evidence-base for further research on cesarean section delivery in Qatar.Keywords: cesarean section, factors, multiple indicator cluster survey, MICS database, Qatar
Procedia PDF Downloads 1163310 Evidence of Total Mercury Biomagnification in Tropical Estuary Lagoon in East Coast of Peninsula, Malaysia
Authors: Quang Dung Le, Kentaro Tanaka, Viet Dung Luu, Kotaro Shirai
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Mercury pollutant is great concerns in globe due to its toxicity and biomagnification through the food web. Recently increasing approaches of stable isotope analyses which have applied in food-web structure are enabled to elucidate more insight trophic transfer of pollutants in ecosystems. In this study, the integration of total mercury (Hg) and stable isotopic analyses (δ13C and δ15N) were measured from basal food sources to invertebrates and fishes in order to determine Hg transfer in Setiu lagoon food webs. The average Hg concentrations showed the increasing trend from low to high trophic levels. The result also indicated that potential Hg exposure from inside mangrove could be higher than that from the tidal flat of mangrove creek. Fish Hg concentrations are highly variable, and many factors driving this variability need further examinations. A positive correlation found between Hg concentrations and δ15N values (the trophic magnification factor was 3.02), suggesting Hg biomagnification through the lagoon food web. Almost all Hg concentrations in fishes and mud crabs did not present a risk for human consumption, however, the Hg concentrations of Caranx ignobilis exceed the permitted level could raise a concern of the potential risk for the marine system. Further investigations should be done to elucidate whether trophic relay relates to high Hg concentrations of some fish species in coastal systems.Keywords: mercury, transfer, stable isotopes, health risk, mangrove, food web
Procedia PDF Downloads 3083309 Moderate Electric Field Influence on Carotenoids Extraction Time from Heterochlorella luteoviridis
Authors: Débora P. Jaeschke, Eduardo A. Merlo, Rosane Rech, Giovana D. Mercali, Ligia D. F. Marczak
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Carotenoids are high value added pigments that can be alternatively extracted from some microalgae species. However, the application of carotenoids synthetized by microalgae is still limited due to the utilization of organic toxic solvents. In this context, studies involving alternative extraction methods have been conducted with more sustainable solvents to replace and reduce the solvent volume and the extraction time. The aim of the present work was to evaluate the extraction time of carotenoids from the microalgae Heterochlorella luteoviridis using moderate electric field (MEF) as a pre-treatment to the extraction. The extraction methodology consisted of a pre-treatment in the presence of MEF (180 V) and ethanol (25 %, v/v) for 10 min, followed by a diffusive step performed for 50 min using a higher ethanol concentration (75 %, v/v). The extraction experiments were conducted at 30 °C and, to keep the temperature at this value, it was used an extraction cell with a water jacket that was connected to a water bath. Also, to enable the evaluation of MEF effect on the extraction, control experiments were performed using the same cell and conditions without voltage application. During the extraction experiments, samples were withdrawn at 1, 5 and 10 min of the pre-treatment and at 1, 5, 30, 40 and 50 min of the diffusive step. Samples were, then, centrifuged and carotenoids analyses were performed in the supernatant. Furthermore, an exhaustive extraction with ethyl acetate and methanol was performed, and the carotenoids content found for this analyses was considered as the total carotenoids content of the microalgae. The results showed that the application of MEF as a pre-treatment to the extraction influenced the extraction yield and the extraction time during the diffusive step; after the MEF pre-treatment and 50 min of the diffusive step, it was possible to extract up to 60 % of the total carotenoids content. Also, results found for carotenoids concentration of the extracts withdrawn at 5 and 30 min of the diffusive step did not presented statistical difference, meaning that carotenoids diffusion occurs mainly in the very beginning of the extraction. On the other hand, the results for control experiments showed that carotenoids diffusion occurs mostly during 30 min of the diffusive step, which evidenced MEF effect on the extraction time. Moreover, carotenoids concentration on samples withdrawn during the pre-treatment (1, 5 and 10 min) were below the quantification limit of the analyses, indicating that the extraction occurred in the diffusive step, when ethanol (75 %, v/v) was added to the medium. It is possible that MEF promoted cell membrane permeabilization and, when ethanol (75 %) was added, carotenoids interacted with the solvent and the diffusion occurred easily. Based on the results, it is possible to infer that MEF promoted the decrease of carotenoids extraction time due to the increasing of the permeability of the cell membrane which facilitates the diffusion from the cell to the medium.Keywords: moderate electric field (MEF), pigments, microalgae, ethanol
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