Search results for: interface formation
1497 Effect of Sulfur on the High-Temperature Oxidation of DIN1.4091
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Centrifugal casting is a metal casting method that uses forces make by centripetal acceleration to distribute molten material in mold. Centrifugal cast parts manufactured in industry contain gas pipes and water supply lines, moreover rings, turbocharger, bushings, brake drums. Turbochargers were exposed to exhaust temperatures of 900-1050°C require a material for the corrosion resistance that will withstand such high component temperatures during the entire service life of the vehicle. Hence, the study of corrosion resistance for turbocharger is important for practical application. DIN1.4091 steels were used widely. The DIN1.4091 steels whose compositions were Fe-34.4Cr-14.5Ni-2.5Mo-0.4W-0.4Mn-0.5Si-(0.009 or 0.35)S (wt.%) were centrifugally cast, and oxidized at 900°C for 50-200 h in order to find the effect of sulfur on the high-temperature oxidation of Fe-34.4Cr-14.5Ni-2.5Mo-0.4W-0.4Mn-0.5Si-(0.009 or 0.35)S (wt.%) alloys. These alloys formed oxide scales that consisted primarily of Cr₂O₃ as the major oxide and Cr₂MnO₄ as the minor one through preferential oxidation of Cr and Mn. Cr formed a thin CrOx oxide film on the surface to prevent further oxidation, and when it is added more than 20%, the sulphide decreased corrosion rate. The high affinity of Mn with S, led to the formation of scattered MnS inclusions, particularly in the 0.35S-containing cast alloy. Sulfur was harmful to the oxidation resistance because it deteriorated the scale/alloy adherence so as to accelerate the adherence and compactness of the formed scales. Acknowledgement: This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2016R1A2B1013169).Keywords: centrifugal casting, turbocharger, sulfur, oxidation, Fe-34.4Cr-14.5Ni alloy
Procedia PDF Downloads 1991496 The Impact of Music on Social Identity Formation and Intergroup Relations in American-Born Korean Skaters in 2018 Winter Olympics
Authors: Sehwan Kim, Jepkorir Rose Chepyator Thomson
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Music provides opportunities to affirm social identities and facilitate the internalization of one’s identity. The purpose of this study was to examine the role of music in breaking down boundaries between the in-group and out-of-group sport participants. Social identity theory was used to guide an understanding of two American-born South Korean skaters—Yura Min and Alexander Gamelin—who used a Korean representative traditional folk song, Arirang, at the 2018 Winter Olympics. This was an interpretive case study that focused on 2018 Winter Olympic participants whose performance and use of music was understood through the lenses of Koreans. Semi-structured interviews were conducted with 15 Korean audiences who watched two American-born South Korean skaters’ performances. Data analysis involved the determination of themes in the data collected. The findings of this study are as follows: First Koreans viewed the skaters as the out-group based on ethnic appearances and stereotypes. Second, Koreans’ inter-group bias against the skaters was meditated after Koreans watched the skaters as they used Arirang song in performance. Implications for this study include the importance of music as an instrument of unity across diverse populations, including intergroup relations. Music can also offer ways to understand people’s cultures and bridge gaps between age and gender across categories of naturalization.Keywords: impact of music, intergroup relations, naturalized athletes, social identity theory
Procedia PDF Downloads 2071495 Experimental Investigation of Gas Bubble Behaviours in a Domestic Heat Pump Water Heating System
Authors: J. B. Qin, X. H. Jiang, Y. T. Ge
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The growing awareness of global warming potential has internationally aroused interest and demand in reducing greenhouse gas emissions produced by human activity. Much national energy in the UK had been consumed in the residential sector mainly for space heating and domestic hot water production. Currently, gas boilers are mostly applied in the domestic water heating which contribute significantly to excessive CO2 emissions and consumption of primary energy resources. The issues can be solved by popularizing heat pump systems that are attributable to higher performance efficiency than those of traditional gas boilers. Even so, the heat pump system performance can be further enhanced if the dissolved gases in its hot water circuit can be efficiently discharged. To achieve this target, the bubble behaviors in the heat pump water heating system need to be extensively investigated. In this paper, by varying different experimental conditions, the effects of various heat pump hot water side parameters on gas microbubble diameters were measured and analyzed. Correspondingly, the effect of each parameter has been investigated. These include varied system pressures, water flow rates, saturation ratios and heat outputs. The results measurement showed that the water flow rate is the most significant parameter to influence on gas microbubble productions. The research outcomes can significantly contribute to the understanding of gas bubble behaviors at domestic heat pump water heating systems and thus the efficient way for the discharging of the associated dissolved gases.Keywords: heat pump water heating system, microbubble formation, dissolved gases in water, effectiveness
Procedia PDF Downloads 2661494 Agarose Based Multifunctional Nanofibrous Bandages for Wound Healing Applications
Authors: Sachin Latiyan, T. S. Sampath Kumar, Mukesh Doble
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Natural polymer based nanofibrous wound dressings have gained increased attention because of their high surface area, bioactivity, biodegradability and resemblance to extracellular matrix. Agarose (a natural polymer) have been used largely for angiogenesis, cartilage formation and wound healing applications. However, electrospinning of agarose is tedious thereby rendering limited studies on fabrication and evaluation of agarose based nanofibrous wound dressings. Thus, present study focuses on the fabrication of agarose (10% w/v)/ polyvinyl alcohol (12% w/v) based multifunctional nanofibrous scaffolds. Zinc citrate (1, 3 and 5% w/w of the polymer) was added as a potential antibacterial agent to combat wound infections. The fabricated scaffolds exhibit ~500% swelling (in phosphate buffer saline) with enhanced mechanical strength which is suitable for most of the wound healing applications. In vitro studies were found to reveal an increased migration and proliferation of L929 mouse fibroblasts with agarose blends w.r.t to the control. The fabricated dressings were found to be effective against both Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacterial strains. Hence, a multifunctional (as provides effective swelling and mechanical support along with antibacterial property), natural product based, eco-friendly scaffold was successfully fabricated to serve as a potential wound dressing material.Keywords: antibacterial dressings, benign solvent, nanofibrous agarose, biocompatibility, enhanced swelling and mechanical strength, biopolymeric dressings
Procedia PDF Downloads 931493 Low-Temperature Fabrication of Reaction Bonded Composites, Based on Sic and (Sic+B4C) Mixture, Infiltrated with Si-Al Alloy
Authors: Helen Dilman, Eyal Oz, Shmuel Hayun, Nahum Frage
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The conventional approach for manufacturing silicon carbide and boron carbide reaction bonded composites is based on infiltrating a ceramic porous preform with molten silicon. The relatively high melting temperature of the silicon infiltrating medium is a drawback of the process. The present contribution is concerned with an approach that allows obtaining reaction bonded composites by pressure-less infiltration at a significantly lower (850-1000oC) temperature range. This approach was applied for the fabrication of fully dense SiC/(Si-Al) and (SiC+B4C)/(Si-Al) composites. The key feature of the approach is based on using Si alloys with low melting temperature and the Mg-vapor atmosphere, under which an adequate wetting between ceramics and liquid alloys for the infiltration process is achieved. In the first set of the experiments ceramic performs compacted from multimodal SiC powders (with the green density of about 27 vol. %) without free carbon addition were infiltrated by Si-20%Al alloy at 950oC. In the second set, 19 vol. % of a fine boron carbide powder was added to SiC powders as a source of carbon. The green density of the SiC-B4C preforms was about 23-25 vol. %. In both cases, successful infiltration was achieved and the composites were fully dense. The density of the composites was about 3g/cm3. For the SiC based composites the hardness value was 750±150HV, Young modulus-280GPa and bending strength-240±30MPa. These values for (SiC-B4C)/(Si-Al) composites (1460±200HV, 317GPa and 360±20MPa) were significantly higher due to the formation of novel ceramics phases. Microstructural characteristics of the composites and their phase composition will be discussed.Keywords: boron carbide, composites, infiltration, low temperatures, silicon carbide
Procedia PDF Downloads 5471492 Effect of Synthesis Parameters on Crystal Size and Perfection of Mordenite and Analcime
Authors: Zehui Du, Chaiwat Prapainainar, Paisan Kongkachuichay, Paweena Prapainainar
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The aim of this work was to obtain small crystalline size and high crystallinity of mordenites and analcimes, by modifying the aging time, agitation, water content, crystallization temperature and crystallization time. Two different hydrothermal methods were studied. Both methods used Na2SiO3 as the silica source, NaAlO2 as the aluminum source, and NaOH as the alkali source. The first method used HMI as the template while the second method did not use the template. Mordenite crystals with spherical shape and bimodal in size of about 1 and 5 µm were obtained from the first method using conditions of 24 hr aging time, 170°C and 24 hr crystallization. Modernites with high crystallinity were formed using agitation system in the crystallization process. It was also found that the aging time of 2 hr and 24 hr did not much affect the formation of mordenite crystals. Analcime crystals were formed in spherical shape and facet on surface with the size between 13-15 µm by the second method using the conditions of 30 minutes aging time, 170°C and 24 hr crystallization without calcination. By increasing water content, the crystallization process was slowed down and resulted in smaller analcime crystals. Larger size of analcime crystals were observed when the samples were calcined at 300°C and 580°C. Higher calcination temperature led to higher crystal growth and resulted in larger crystal size. Finally, mordenite and analcime was used as fillers in zeolite/Nafion composite membrane to solve the fuel cross over problem in direct alcohol fuel cell.Keywords: analcime, hydrothermal synthesis, mordenite, zeolite
Procedia PDF Downloads 2641491 Modeling Operating Theater Scheduling and Configuration: An Integrated Model in Health-Care Logistics
Authors: Sina Keyhanian, Abbas Ahmadi, Behrooz Karimi
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We present a multi-objective binary programming model which considers surgical cases are scheduling among operating rooms and the configuration of surgical instruments in limited capacity hospital trays, simultaneously. Many mathematical models have been developed previously in the literature addressing different challenges in health-care logistics such as assigning operating rooms, leveling beds, etc. But what happens inside the operating rooms along with the inventory management of required instruments for various operations, and also their integration with surgical scheduling have been poorly discussed. Our model considers the minimization of movements between trays during a surgery which recalls the famous cell formation problem in group technology. This assumption can also provide a major potential contribution to robotic surgeries. The tray configuration problem which consumes surgical instruments requirement plan (SIRP) and sequence of surgical procedures based on required instruments (SIRO) is nested inside the bin packing problem. This modeling approach helps us understand that most of the same-output solutions will not be necessarily identical when it comes to the rearrangement of surgeries among rooms. A numerical example has been dealt with via a proposed nested simulated annealing (SA) optimization approach which provides insights about how various configurations inside a solution can alter the optimal condition.Keywords: health-care logistics, hospital tray configuration, off-line bin packing, simulated annealing optimization, surgical case scheduling
Procedia PDF Downloads 2821490 Modification Of Rubber Swab Tool With Brush To Reduce Rubber Swab Fraction Fishing Time
Authors: T. R. Hidayat, G. Irawan, F. Kurniawan, E. H. I. Prasetya, Suharto, T. F. Ridwan, A. Pitoyo, A. Juniantoro, R. T. Hidayat
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Swab activities is an activity to lift fluid from inside the well with the use of a sand line that aims to find out fluid influx after conducting perforation or to reduce the level of fluid as an effort to get the difference between formation pressure with hydrostatic pressure in the well for underbalanced perforation. During the swab activity, problems occur frequent problems occur with the rubber swab. The rubber swab often breaks and becomes a fish inside the well. This rubber swab fishing activity caused the rig operation takes longer, the swab result data becomes too late and create potential losses of well operation for the company. The average time needed for fishing the fractions of rubber swab plus swab work is 42 hours. Innovation made for such problems is to modify the rubber swab tool. The rubber swab tool is modified by provided a series of brushes at the end part of the tool with a thread of connection in order to improve work safety, so when the rubber swab breaks, the broken swab will be lifted by the brush underneath; therefore, it reduces the loss time for rubber swab fishing. This tool has been applied, it and is proven that with this rubber swab tool modification, the rig operation becomes more efficient because it does not carry out the rubber swab fishing activity. The fish fractions of the rubber swab are lifted up to the surface. Therefore, it saves the fuel cost, and well production potentials are obtained. The average time to do swab work after the application of this modified tool is 8 hours.Keywords: rubber swab, modifikasi swab, brush, fishing rubber swab, saving cost
Procedia PDF Downloads 1671489 Exploring the Process of Change in the Identity Constructs of Adolescents Exposed to Family Violence
Authors: Charlene Petersen, Herman Grobler, Karel Botha
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Exposure to family violence has an impact on adolescent development, more specifically the identity process. This article explores the process of change in identity constructs of adolescents’ exposed to family violence in a Cape Town community in South Africa. In order to understand the process of identity formation the article explores and describes how the meaning that these adolescents give to family violence can contribute to change in their identity constructs. A mixed method approached was used in the study. A psycho-education strategy was implemented as the intervention and pretest-post-test scales were used to assess for change after the intervention process. Twelve participants were purposely selected for the study and included both male and female adolescents with ages ranging from 15 to 18 years from three secondary schools. The research data for this article were mainly extracted from the pre-test post-test design and the psycho-education strategy of the overall research study. The research results of the psycho-education strategy were thematically analyzed and a statistical procedure was used to measure for significant change within pre-test-post-test scales. The research merely refers to the outcome of psycho-education strategy and how it correlates with the outcome of the pre-test post-test design. Adolescents’ exposure to a psycho-education strategy, as well the pre-test post-test findings reveal a change within identity construct in terms of how they perceive themselves and interaction with others in the context of family violence.Keywords: process of change in adolescent identity, family violence, psycho-education strategy, pre and post assessment
Procedia PDF Downloads 4761488 Combined Synchrotron Radiography and Diffraction for in Situ Study of Reactive Infiltration of Aluminum into Iron Porous Preform
Authors: S. Djaziri, F. Sket, A. Hynowska, S. Milenkovic
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The use of Fe-Al based intermetallics as an alternative to Cr/Ni based stainless steels is very promising for industrial applications that use critical raw materials parts under extreme conditions. However, the development of advanced Fe-Al based intermetallics with appropriate mechanical properties presents several challenges that involve appropriate processing and microstructure control. A processing strategy is being developed which aims at producing a net-shape porous Fe-based preform that is infiltrated with molten Al or Al-alloy. In the present work, porous Fe-based preforms produced by two different methods (selective laser melting (SLM) and Kochanek-process (KE)) are studied during infiltration with molten aluminum. In the objective to elucidate the mechanisms underlying the formation of Fe-Al intermetallic phases during infiltration, an in-house furnace has been designed for in situ observation of infiltration at synchrotron facilities combining x-ray radiography (XR) and x-ray diffraction (XRD) techniques. The feasibility of this approach has been demonstrated, and information about the melt flow front propagation has been obtained. In addition, reactive infiltration has been achieved where a bi-phased intermetallic layer has been identified to be formed between the solid Fe and liquid Al. In particular, a tongue-like Fe₂Al₅ phase adhering to the Fe and a needle-like Fe₄Al₁₃ phase adhering to the Al were observed. The growth of the intermetallic compound was found to be dependent on the temperature gradient present along the preform as well as on the reaction time which will be discussed in view of the different obtained results.Keywords: combined synchrotron radiography and diffraction, Fe-Al intermetallic compounds, in-situ molten Al infiltration, porous solid Fe preforms
Procedia PDF Downloads 2261487 Valorization of Waste Reverse Osmosis Desalination Brine and Crystallization Sequence Approach for Kainite Recovery
Authors: Ayoub Bouazza, Ali Faddouli, Said Amal, Rachid Benhida, Khaoula Khaless
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Brine waste generated from reverse osmosis (RO) desalination plants contains various valuable compounds, mainly salts, trace elements, and organic matter. These wastes are up to two times saltier than standard seawater. Therefore, there is a strong economic interest in recovering these salts. The current practice in desalination plants is to reject the brine back to the sea, which affects the marine ecosystem and the environment. Our study aims to bring forth a reliable management solution for the valorisation of waste brines. Natural evaporation, isothermal evaporation at 25°C and 50°C, and evaporation using continuous heating were used to crystallize valuable salts from a reverse osmosis desalination plant brine located on the Moroccan Atlantic coast. The crystallization sequence of the brine was studied in comparison with standard seawater. The X-Ray Diffraction (XRD) of the precipitated solid phases showed similar results, where halite was the main solid phase precipitated from both the brine and seawater. However, Jänecke diagram prediction, along with FREZCHEM simulations, showed that Kainite should crystallize before Epsomite and Carnallite. As the absence of kainite formation in many experiments in the literature has been related to the metastability of kainite and the critical relative humidity conditions, and the precipitation of K–Mg salts is very sensitive to climatic conditions. An evaporation process is proposed as a solution to achieve the predicted crystallization path and to affirm the recovery of Kainite.Keywords: salts crystallization, reverse osmosis, solar evaporation, frezchem, ZLD
Procedia PDF Downloads 1031486 The Effect of Metacognitive Think-Aloud Strategy on Form 1 Pupils’ Reading Comprehension Skills via DELIMa Platform
Authors: Fatin Khairani Khairul 'Azam
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Reading comprehension requires the formation of an articulate mental representation of the information in a text. It involves three interdepended elements—the reader, the text, and the activity, all situated into an extensive sociocultural context. Incorporating metacognitive think-aloud strategy into teaching reading comprehension would improve learners’ reading comprehension skills as it helps to monitor their thinking as they read. Furthermore, by integrating Digital Educational Learning Initiative Malaysia (DELIMa) platform in teaching reading comprehension, it can make the process interactive and fun. A quasi-experimental one-group pre-test post-test design was used to identify the effectiveness of using metacognitive think-aloud strategy via DELIMa platform in improving pupils’ reading comprehension performance and their perceptions towards reading comprehension. The participants of the study comprised 82 of form 1 pupils from a secondary school in Pasir Gudang, Johor, Malaysia. All participants were required to sit for pre-and post-tests to track their reading comprehension performance and perceptions. The findings revealed that incorporating metacognitive think-aloud strategy is an effective strategy in teaching reading comprehension as the performance of pupils in reading comprehension and their perceptions towards reading comprehension were improved during the post tests. It is hoped that the findings of the study would be useful to the teachers incorporating the same strategy in teaching to improve pupils' reading skills. It is suggested that future study should involve the motivation factor of the participants on incorporating think-aloud strategy into teaching reading comprehension as well.Keywords: DELIMa Platform, ESL Learners, Metacognitive Strategy, Pupils' Perceptions, Reading Comprehension, Think-Aloud Strategy
Procedia PDF Downloads 2101485 A Study of The Contrasts and Cultural Commonalities of the Hazara and Uzbek Peoples of Afghanistan
Authors: Sadullah Rahmani
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Legends, stories, beliefs and traditions in every nation represent the collective dreams, secrets and aspirations of a nation and on the other hand, the foundation of their collective memory; What generally forms the foundation of the culture of any nation has undergone changes and transformations due to the passage of time and changes in political, religious and social conditions. Afghanistan is one of the richest countries in terms of cultural diversity. This country is home to people of different languages, ethnicities and religions. The purpose of this article is to analyze the contrasts and cultural commonalities between two ethnic groups in Afghanistan, namely the Hazara and Uzbek peoples. This research was done with qualitative method and structured interview tool. The method of data analysis is content analysis. In order to explain the intercultural sensitivities of the two groups, Milton Bennett's intercultural sensitivities measures have been used. Based on the theory of intercultural sensitivities, the development of communication is an important factor in reducing intercultural sensitivities. In this research, 8 people from the Hazara and Uzbek tribes were interviewed. Various factors such as customs and manners, music, language, art, lifestyle, etc. have been examined in the article. These factors can contribute to cultural differences and commonalities between the Hazara and Uzbek peoples. The results of this research show that according to Bennett's theory, there are less cultural sensitivities between the Hazara and Uzbek peoples of Afghanistan, especially in matters of marriage, language, economic poverty, being discriminated against, and work relationships; But cultural sensitivities are more in many other cases such as education, religion and the formation of cultural communities.Keywords: Keywords: Uzbek, language, culture, religion, Hazara.
Procedia PDF Downloads 361484 The Compositional Effects on Electrospinning of Gelatin and Polyvinyl-alcohol Mixed Nanofibers
Authors: Yi-Chun Wu, Nai-Yun Chang, Chuan LI
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This study investigates a feasible range of composition for the mixture of gelatin and polyvinyl alcohol to form nanofibers by electrospinning. Gelatin, one of the most available naturally derived hydrogels of amino acids, is a popular choice for food additives, cosmetic ingredients, biomedical implants, or dressing of its non-toxic and biodegradable nature. Nevertheless, synthetic hydrogel polyvinyl alcohol has long been used as a thickening agent for adhesion purposes. Many biomedical devices are also containing polyvinyl-alcohol as a major content, such as eye drops and contact lenses. To discover appropriate compositions of gelatin and polyvinyl-alcohol for electrospun nanofibers, polymer solutions of different volumetric ratios between gelatin and polyvinyl alcohol were prepared for electrospinning. The viscosity, surface tension, pH value, and electrical conductance of polymer solutions were measured. On the nanofibers, the vibrational modes of molecular structures in nanofibers were investigated by Fourier-transform infrared spectroscopy. The morphologies and surface chemical elements of fibers were examined by the scanning electron microscope and the energy-dispersive X-ray spectroscopy. The hydrophilicity of nanofiberswas evaluated by the water contact angles on the surface of the fibers. To further test the biotoxicity of nanofibers, an in-vitro 3T3 fibroblasts culture further tested the biotoxicity of the electrospun nanofibers. Throughstatistical analyses of the experimental data, it is found that the polyvinyl-alcohol rich composition (the volumetric ratio of gelatin/polyvinyl-alcohol < 1) would be a preferable choice for the formation of nanofibers by the current setup of electrospinning. These electrospun nanofibers tend to be hydrophilic with no biotoxicity threat to the 3T3 fibroblasts.Keywords: gelatin, polyvinyl-alcohol, nanofibers, electrospinning, spin coating
Procedia PDF Downloads 851483 Criminal Responsibility of Minors in Russia: The Age of Liability and Penalties
Authors: Natalia Selezneva
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The level of crime depends on a number of factors, such as political and economic instability, social inequality and ineffective legislation. A special place in the overall level of crime takes juvenile delinquency. United Nations Standard Minimum developed rules for the administration of juvenile justice (The Beijing Rules), in order to ensure the rights of juvenile offenders under the various legal systems. Most countries support these recommendations, and Russia is no exception. Russia's criminal code establishes the minimum age of criminal liability; types of crimes for which the possible involvement of minors to justice; punishment; sentencing and execution of punishment for minors. However, these provisions cause heated debates in the scientific literature. The high level of juvenile crime indicates the ineffectiveness of legal regulation of criminal liability of minors. In order to ensure compliance with international standards require new and modern approaches to improve national legislation and practice of its application. Achieving this goal will be achieved through the following tasks: 1. Create sub-branches of law regulating the legal status of minors; 2. Improving the types of penalties; 3. The possibility of using alternative measures; 4. The introduction of the procedure of extrajudicial settlement of the conflict. The criminal law of each country depends on the historical, national and cultural characteristics. The development of the Russian legislation taking into account international experience is extremely essential and will be a new stage in the formation of a legal state, especially in the sphere of protection of the rights of juvenile offenders.Keywords: criminal law, juvenile offender, punishment, the age of criminal responsibility
Procedia PDF Downloads 5431482 Effect of Varying Scaffold Architecture and Porosity of Calcium Alkali Orthophosphate Based-Scaffolds for Bone Tissue Engineering
Authors: D. Adel, F. Giacomini, R. Gildenhaar, G. Berger, C. Gomes, U. Linow, M. Hardt, B. Peleskae, J. Günster, A. Houshmand, M. Stiller, A. Rack, K. Ghaffar, A. Gamal, M. El Mofty, C. Knabe
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The goal of this study was to develop 3D scaffolds from a silica containing calcium alkali orthophosphate utilizing two different fabrication processes, first a replica technique namely the Schwartzwalder Somers method (SSM), and second 3D printing, i.e. Rapid prototyping (RP). First, the mechanical and physical properties of the scaffolds (porosity, compressive strength, and solubility) was assessed and second their potential to facilitate homogenous colonization with osteogenic cells and extracellular bone matrix formation throughout the porous scaffold architecture. To this end murine and rat calavarie osteoblastic cells were dynamically seeded on both scaffold types under perfusion with concentrations of 3 million cells. The amount of cells and extracellular matrix as well as osteogenic marker expression was evaluated using hard tissue histology, immunohistochemistry, and histomorphometric analysis. Total porosities of both scaffolds were 86.9 % and 50% for SSM and RP respectively, Compressive strength values were 0.46 ± 0.2 MPa for SSM and 6.6± 0.8 MPa for RP. Regarding the cellular behavior, RP scaffolds displayed a higher cell and matrix percentage of 24.45%. Immunoscoring yielded strong osteocalcin expression of cells and matrix in RP scaffolds and a moderate expression in SSM scaffolds. 3D printed RP scaffolds displayed superior mechanical and biological properties compared to SSM. 3D printed scaffolds represent excellent candidates for bone tissue engineering.Keywords: calcium alkali orthophosphate, extracellular matrix mineralization, osteoblast differentiation, rapid prototyping, scaffold
Procedia PDF Downloads 3311481 A Study on Architectural Characteristics of Traditional Iranian Ordinary Houses in Mashhad, Iran
Authors: Rana Daneshvar Salehi
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In many Iranian cities including Mashhad, the capital of Razavi Khorasan Province, ordinary samples of domestic architecture on a small scale is not considered as heritage. While the principals of house formation are respected in all traditional Iranian houses; from moderate to great ones. During the past decade, Mashhad has lost its identity, and has become a modern city. Identifying it as the capital of the Islamic Culture in 2017 by ISESCO and consequently looking for new developments and transfiguration caused to demolish a large number of traditional modest habitation. For this reason, the present paper aims to introduce the three undiscovered houses with the historical and monumental values located in the oldest neighborhoods of Mashhad which have been neglected in the cultural heritage field. The preliminary phase of this approach will be a measured survey to identify the significant characteristics of selected dwellings and understand the challenges through focusing on building form, orientation, room function, space proportion and ornamental elements’ details. A comparison between the case studies and the wealthy domestically buildings presents that a house belongs to inhabitants with an average income could introduce the same accurate, regular, harmonic and proportionate design which can be found in the great mansions. It reveals that an ordinary traditional house can be regarded as valuable construction not only for its historical characteristics but also for its aesthetical and architectural features that could avoid further destructions in the future.Keywords: traditional ordinary house, architectural characteristic, proportion, heritage
Procedia PDF Downloads 1461480 Effect of Variation of Temperature Distribution on Mechanical Properties of Shield Metal Arc Welded Duplex Stainless Steel
Authors: Arvind Mittal, Rajesh Gupta
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Influence of heat input on the micro structure and mechanical properties of shield metal arc welded of duplex stainless steel UNSNO.S-31803 has been investigated. Three heat input combinations designated as low heat (0.675 KJ/mm), medium heat (0.860 KJ/mm) and high heat (1.094 KJ/mm) and weld joints made using these combinations were subjected to micro structural evaluations and tensile and impact testing so as to analyze the effect of thermal arc energy on the micro structure and mechanical properties of these joints. The result of this investigation shows that the joints made using low heat input exhibited higher tensile strength than those welded with medium and high heat input. Heat affected zone of welded joint made with medium heat input has austenitic ferritic grain structure with some patchy austenite provide high toughness. Significant grain coarsening was observed in the heat affected zone (HAZ) of medium and high heat input welded joints, whereas low heat input welded joint shows the fine grain structure in the heat affected zone with small amount of dendritic formation and equiaxed grain structure where inner zone indicates slowly cooled grains in the direction of heat dissipation. This is the main reason for the observable changes of tensile properties of weld joints welded with different arc energy inputs.Keywords: microstructure, mechanical properties, shield metal arc welded, duplex stainless steel
Procedia PDF Downloads 2791479 Macrocycles Enable Tuning of Uranyl Electrochemistry by Lewis Acids
Authors: Amit Kumar, Davide Lionetti, Victor Day, James Blakemore
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Capture and activation of the water-soluble uranyl dication (UO22+) remains a challenging problem, as few rational approaches are available for modulating the reactivity of this species. Here, we report the divergent synthesis of heterobimetallic complexes in which UO22+ is held in close proximity to a range of redox-inactive metals by tailored macrocyclic ligands. Crystallographic and spectroscopic studies confirm assembly of homologous UVI(μ-OAr)2Mn+ cores with a range of mono-, di-, and trivalent Lewis acids (Mn+). X-ray diffraction (XRD) and cyclic voltammetry (CV) data suggest preferential binding of K+ in an 18-crown-6-like cavity and Na+ in a 15-crown-5-like cavity, both appended to Schiff-base type sites that selectively bind UO22+. CV data demonstrate that the UVI/UV reduction potential in these complexes shifts positive and the rate of electron transfer decreases with increasing Lewis acidity of the incorporated redox-inactive metals. Moreover, spectroelectrochemical studies confirm the formation of [UV] species in the case of monometallic UO22+ complex, consistent with results from prior studies. However, unique features were observed during spectroelectrochemical studies in the presence of the K+ ion, suggesting new insights into electronic structure may be accessible with the heterobimetallic complexes. Overall, these findings suggest that interactions with Lewis acids could be effectively leveraged for rational tuning of the electronic and thermochemical properties of the 5f elements, reminiscent of strategies more commonly employed with 3d transition metals.Keywords: electrochemistry, Lewis acid, macrocycle, uranyl
Procedia PDF Downloads 1421478 The Contact between a Rigid Substrate and a Thick Elastic Layer
Authors: Nicola Menga, Giuseppe Carbone
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Although contact mechanics has been widely focused on the study of contacts between half-space, it has been recently pointed out that in presence of finite thickness elastic layers the results of the contact problem show significant difference in terms of the main contact quantities (e.g. contact area, penetration, mean pressure, etc.). Actually, there exist a wide range of industrial application demanding for this kind of studies, such as seals leakage prediction or pressure-sensitive coatings for electrical applications. In this work, we focus on the contact between a rigid profile and an elastic layer of thickness h confined under two different configurations: rigid constrain and applied uniform pressure. The elastic problem at hand has been formalized following Green’s function method and then numerically solved by means of a matrix inversion. We study different contact conditions, both considering and neglecting adhesive interactions at the interface. This leads to different solution techniques: Adhesive contacts equilibrium solution is found, in term of contact area for given penetration, making stationary the total free energy of the system; whereas, adhesiveless contacts are addressed defining an equilibrium criterion, again on the contact area, relying on the fracture mechanics stress intensity factor KI. In particular, we make the KI vanish at the edges of the contact area, as peculiar for adhesiveless elastic contacts. The results are obtained in terms of contact area, penetration, and mean pressure for both adhesive and adhesiveless contact conditions. As expected, in the case of a uniform applied pressure the slab turns out much more compliant than the rigidly constrained one. Indeed, we have observed that the peak value of the contact pressure, for both the adhesive and adhesiveless condition, is much higher for the rigidly constrained configuration than in the case of applied uniform pressure. Furthermore, we observed that, for little contact area, both systems behave the same and the pull-off occurs at approximately the same contact area and mean contact pressure. This is an expected result since in this condition the ratio between the layers thickness and the contact area is very high and both layer configurations recover the half-space behavior where the pull-off occurrence is mainly controlled by the adhesive interactions, which are kept constant among the cases.Keywords: contact mechanics, adhesion, friction, thick layer
Procedia PDF Downloads 5121477 Towards Kurdish Internet Linguistics: A Case Study on the Impact of Social Media on Kurdish Language
Authors: Karwan K. Abdalrahman
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Due to the impacts of the internet and social media, new words and expressions enter the Kurdish language, and a number of familiarized words get new meanings. The case is especially true when the technique of transliteration is taken into consideration. Through transliteration, a number of selected words widely used on social media are entering the Kurdish media discourse. In addition, a selected number of Kurdish words get new cultural and psychological meanings. The significance of this study is to delve into the process of word formation in the Kurdish language and explore how new words and expressions are formed by social media users and got public recognition. First, the study investigates the English words that enter the Kurdish language through different social media platforms. All of these words are transliterated and are used in spoken and written discourses. Second, there are a specific number of Kurdish words that got new meanings in social media. As for these words, there are psychological and cultural factors that make people use these expressions for specific political reasons. It can be argued that they have an indirect political message along with their new linguistic usages. This is a qualitative study analyzing video content that was published in the last two years on social media platforms, including Facebook and YouTube. The collected data was analyzed based on the themes discussed above. The findings of the research can be summarized as follows: the widely used transliterated words have entered both the spoken and written discourses. Authors in online and offline newspapers, TV presenters, literary writers, columnists are using these new expressions in their writings. As for the Kurdish words with new meanings, they are also widely used for psychological, cultural, and political reasons.Keywords: Kurdish language, social media, new meanings, transliteration, vocabulary
Procedia PDF Downloads 1811476 Chemopreventive Efficacy Of Cdcl2(C14H21N3O2) in Rat Colon Carcinogenesis Model Using Aberrant Crypt Foci (ACF) as Endpoint Marker
Authors: Maryam Hajrezaie, Mahmood Ameen Abdulla, Nazia AbdulMajid, Maryam Zahedifard
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Colon cancer is one of the most prevalent cancers in the world. Cancer chemoprevention is defined as the use of natural or synthetic compounds capable of inducing biological mechanisms necessary to preserve genomic fidelity. New schiff based compounds are reported to exhibit a wide spectrum of biological activities of therapeutic importance. To evaluate inhibitory properties of CdCl2(C14H21N3O2) complex on colonic aberrant crypt foci, five groups of 7-week-old male rats were used. Control group was fed with 10% Tween 20 once a day, cancer control group was intra-peritoneally injected with 15 mg/kg Azoxymethan, drug control group was injected with 15 mg/kg azoxymethan and 5-Flourouracil, experimental groups were fed with 2.5 and 5 mg/kg CdCl2(C14H21N3O2) compound each once a day. Administration of compound were found to be effectively chemoprotective. Andrographolide suppressed total colonic ACF formation up to 72% to 74%, respectively, when compared with control group. The results also showed a significant increase in glutathione peroxidase, superoxide dismutase, catalase activities and a decrease in malondialdehyde level. Immunohistochemical staining demonstrated down-regulation of PCNA protein. According to the Western blot comparison analysis, COX-2 and Bcl2 is up-regulated whilst the Bax is down-regulated. according to these data, this compound plays promising chemoprotective activity, in a model of AOM-induced in ACF.Keywords: chemopreventive, Schiff based compound, aberrant crypt foci (ACF), immunohistochemical staining
Procedia PDF Downloads 4021475 Experimental Characterization of Anti-Icing System and Accretion of Re-Emitted Droplets on Turbojet Engine Blades
Authors: Guillaume Linassier, Morgan Balland, Hugo Pervier, Marie Pervier, David Hammond
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Atmospheric icing for turbojet is caused by ingestion of super-cooled water droplets. To prevent operability risks, manufacturer can implement ice protection systems. Thermal systems are commonly used for this purpose, but their activation can cause the formation of a water liquid film, that can freeze downstream the heated surface or even on other components. In the framework of STORM, a European project dedicated to icing physics in turbojet engines, a cascade rig representative of engine inlet blades was built and tested in an icing wind tunnel. This mock-up integrates two rows of blades, the upstream one being anti-iced using an electro-thermal device the downstream one being unheated. Under icing conditions, the anti-icing system is activated and set at power level to observe a liquid film on the surface and droplet re-emission at the trailing edge. These re-emitted droplets will impinge on the downstream row and contribute to ice accretion. A complete experimental database was generated, including the characterization of ice accretion shapes, and the characterization of electro-thermal anti-icing system (power limit for apparition of the runback water or ice accretion). These data will be used for validation of numerical tools for modeling thermal anti-icing systems in the scope of engine application, as well as validation of re-emission droplets model for stator parts.Keywords: turbomachine, anti-icing, cascade rig, runback water
Procedia PDF Downloads 1821474 Development of a Sprayable Piezoelectric Material for E-Textile Applications
Authors: K. Yang, Y. Wei, M. Zhang, S. Yong, R. Torah, J. Tudor, S. Beeby
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E-textiles are traditional textiles with integrated electronic functionality. It is an emerging innovation with numerous applications in fashion, wearable computing, health and safety monitoring, and the military and medical sectors. The piezoelectric effect is a widespread and versatile transduction mechanism used in sensor and actuator applications. Piezoelectric materials produce electric charge when stressed. Conversely, mechanical deformation occurs when an electric field is applied across the material. Lead Zirconate Titanate (PZT) is a widely used piezoceramic material which has been used to fabricate e-textiles through screen printing, electro spinning and hydrothermal synthesis. This paper explores an alternative fabrication process: Spray coating. Spray coating is a straightforward and cost effective fabrication method applicable on both flat and curved surfaces. It can also be applied selectively by spraying through a stencil which enables the required design to be realised on the substrate. This work developed a sprayable PZT based piezoelectric ink consisting of a binder (Fabink-Binder-01), PZT powder (80 % 2 µm and 20 % 0.8 µm) and acetone as a thinner. The optimised weight ratio of PZT/binder is 10:1. The components were mixed using a SpeedMixer DAC 150. The fabrication processes is as follows: 1) Screen print a UV-curable polyurethane interface layer on the textile to create a smooth textile surface. 2) Spray one layer of a conductive silver polymer ink through a pre-designed stencil and dry at 90 °C for 10 minutes to form the bottom electrode. 3) Spray three layers of the PZT ink through a pre-designed stencil and dry at 90 °C for 10 minutes for each layer to form a total thickness of ~250µm PZT layer. 4) Spray one layer of the silver ink through a pre-designed stencil on top of the PZT layer and dry at 90 °C for 10 minutes to form the top electrode. The domains of the PZT elements were aligned by polarising the material at an elevated temperature under a strong electric field. A d33 of 37 pC/N has been achieved after polarising at 90 °C for 6 minutes with an electric field of 3 MV/m. The application of the piezoelectric textile was demonstrated by fabricating a pressure sensor to switch an LED on/off. Other potential applications on e-textiles include motion sensing, energy harvesting, force sensing and a buzzer.Keywords: piezoelectric, PZT, spray coating, pressure sensor, e-textile
Procedia PDF Downloads 4651473 Activation-TV® to Reduce Elderly Loneliness and Insecurity
Authors: Hannele Laaksonen, Seija Nyqvist, Kari Nurmes
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Objectives: In the year 2011 the City of Vaasa started to develop know-how in the technology and the introduction of services for aging people in cooperation with the Polytechnic Novia University of Applied Sciences and VAMK, University of Applied Sciences. The project´s targets included: to help elderly people to maintain their ability to function, to provide them social and physical activities, to prevent their social exclusion, to decrease their feelings of loneliness and insecurity and to develop their technical know-how. Methods: The project was built based on open source code, tailor-made service system and user interface for the elderly living at home and their families, based on the users´ expectations and experiences of services. Activation-TV®-project vas carried out 1.4.2011-31.3.2014. A pilot group of eight elderly persons, who were living at home, were selected to the project. All necessary technical means as well as guidance and teaching equipment were provided to the pilot group. The students of University of Applied Sciences (VAMK, Novia) and employees of Center of Ageing were made all programs to the Activation-TV®. The project group were interviewed after and before intervention. The data were evaluated both qualitatively and quantitatively. Results: The built service includes a video library, a group room for interactive programs and a personal room for bilateral meetings and direct shipment. The program is bilingual and produced in both national languages. The Activation TV® reduced elderly peoples´ (n=8) feelings of emptiness, added mental well-being and quality of life with social contacts. Relatives felt, that they were able to get in to older peoples´ everyday life with Activation TV®. Discussion: The built application was tailored to the model that has not been developed elsewhere in Finland. This model can be copied from one server to another and thus transferred to other municipalities but the program requires its own personnel system management and maintenance as well as program production cooperation between the different actors. This service can be used for the elderly who are living at home without dementia.Keywords: mental well-being, quality of life, elderly people, Finland
Procedia PDF Downloads 3431472 Photocatalysis with Fe/Ti-Pillared Clays for the Oxofunctionalization of Alkylaromatics by O2
Authors: Houria Rezala, Jose Luis Valverde, Amaya Romero, Alessandra Molinari, Andrea Maldotti
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A pillared montmorillonite containing iron doped titania (Fe/Ti-PILC) has been prepared from a natural clay. This material has been characterized by X-ray diffraction, nitrogen adsorption, temperature programmed desorption of ammonia, inductively coupled plasma atomic emission spectroscopy, atomic absorption, and diffuse reflectance UV-VIS spectroscopy. The layer structure of Fe/Ti-PILC resulted to be ordered with an insertion of pillars, which caused a slight increase in the basal spacing of the clay. Its specific surface area was about three times larger than that of the parent Na-montmorillonite due principally to the creation of a remarkable microporous network. The doped material was a robust photocatalyst able to oxidize liquid alkyl aromatics to the corresponding carbonylic derivatives, using O2 as the oxidizing species, at mild pressure and temperature conditions. Accumulation of valuable carbonylic derivatives was possible since their over-oxidation to carbon dioxide was negligible. Fe/Ti-PILC was able to discriminate between toluene and cyclohexane in favor of the aromatic compound with an efficiency that is about three times higher than that of titanium pillared clays (Ti-PILC). It is likely that the addition of iron favored the formation of new acid sites able to interact with the aromatic substrate. Iron doping caused a significant TiO2 visible light-induced activity (wavelength > 400 nm) with only minor negative effects on its performance under UV-light irradiation (wavelength > 290 nm).Keywords: alkyl aromatics oxidation, heterogeneous photocatalysis, iron doping, pillared clays
Procedia PDF Downloads 4511471 Relevance of Copyright and Trademark in the Gaming Industry
Authors: Deeksha Karunakar
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The gaming industry is one of the biggest industries in the world. Video games are interactive works of authorship that require the execution of a computer programme on specialized hardware but which also incorporate a wide variety of other artistic mediums, such as music, scripts, stories, video, paintings, and characters, into which the player takes an active role. Therefore, video games are not made as singular, simple works but rather as a collection of elements that, if they reach a certain level of originality and creativity, can each be copyrighted on their own. A video game is made up of a wide variety of parts, all of which combine to form the overall sensation that we, the players, have while playing. The entirety of the components is implemented in the form of software code, which is then translated into the game's user interface. Even while copyright protection is already in place for the coding of software, the work that is produced because of that coding can also be protected by copyright. This includes the game's storyline or narrative, its characters, and even elements of the code on their own. In each sector, there is a potential legal framework required, and the gaming industry also requires legal frameworks. This represents the importance of intellectual property laws in each sector. This paper will explore the beginnings of video games, the various aspects of game copyrights, and the approach of the courts, including examples of a few different instances. Although the creative arts have always been known to draw inspiration from and build upon the works of others, it has not always been simple to evaluate whether a game has been cloned. The video game business is experiencing growth as it has never seen before today. The majority of today's video games are both pieces of software and works of audio-visual art. Even though the existing legal framework does not have a clause specifically addressing video games, it is clear that there is a great many alternative means by which this protection can be granted. This paper will represent the importance of copyright and trademark laws in the gaming industry and its regulations with the help of relevant case laws via utilizing doctrinal methodology to support its findings. The aim of the paper is to make aware of the applicability of intellectual property laws in the gaming industry and how the justice system is evolving to adapt to such new industries. Furthermore, it will provide in-depth knowledge of their relationship with each other.Keywords: copyright, DMCA, gaming industry, trademark, WIPO
Procedia PDF Downloads 691470 Thermo-Mechanical Behavior of Steel-Wood Connections of Wooden Structures Under the Effect of a Fire
Authors: Ahmed Alagha, Belkacem Lamri, Abdelhak Kada.
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Steel-wood assemblies often have complex geometric configurations whose overall behavior under the effect of a fire is conditioned by the thermal response, by combining the two materials steel and wood, whose thermal characteristics are greatly influenced by high temperatures. The objective of this work is to study the thermal behavior of a steel-wood connection, with or without insulating material, subjected to an ISO834 standard fire model. The analysis is developed by the analytical approach using the Eurocode, and numerically, by the finite element method, through the ANSYS calculation code. The design of the connections is evaluated at room temperature taking the cases of single shear and double shear. The thermal behavior of the connections is simulated in transient state while taking into account the modes of heat transfer by convection and by radiation. The variation of temperature as a function of time is evaluated in different positions of the connections while talking about the heat produced and the formation of the carbon layer. The results relate to the temperature distributions in the connection elements as a function of the duration of the fire. The results of the thermal analysis show that the temperature increases rapidly and reaches more than 260 °C in the steel material for an hour of exposure to fire. The temperature development in wood material is different from that in steel because of its thermal properties. Wood heats up on the outside and burns, its surface can reach very high temperatures in points on the surface.Keywords: Eurocode 5, finite elements, ISO834, simple shear, thermal behaviour, wood-steel connection
Procedia PDF Downloads 861469 New Targets Promoting Oncolytic Virotherapy
Authors: Felicia Segeth, Florian G. Klein, Lea Berger, Andreas Kolk, Per S. Holm
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The entry of oncolytic viruses (OVs) into clinical application opens groundbreaking changes in current and future treatment regimens. However, despite their potent anti-cancer activity in vitro, clinical studies revealed limitations of OVs as monotherapy. The same applies to CDK 4/6 inhibitors (CDK4/6i) targeting cell cycle as well as bromodomain and extra-terminal domain inhibitors (BETi) targeting gene expression. In this study, the anti-tumoral effect of XVir-N-31, an YB-1 dependent oncolytic adenovirus, was evaluated in combination with Ribociclib, a CDK4/6i, and JQ1, a BETi. The head and neck squamous cell carcinoma (HNSCC) cell lines Fadu, SAS, and Cal-33 were used. DNA replication and gene expression of XVir-N-31 was measured by RT-qPCR, protein expression by western blotting, and cell lysis by SRB assays. Treatment with CDK4/6i and BETi increased viral gene expression, viral DNA replication, and viral particle formation. The data show that the combination of oncolytic adenovirus XVir-N-31 with CDK4/6i & BETi acts highly synergistic in cancer cell lysis. Furthermore, additional molecular analyses on this subject demonstrate that the positive transcription elongation factor P-TEFb plays a decisive role in this regard, indicating an influence of the combinational therapy on gene transcription control. The combination of CDK4/6i & BETi and XVir-N-31 is an attractive strategy to achieve substantial cancer cell killing and is highly suitable for clinical testing.Keywords: adenovirus, BET, CDK4/6, HNSCC, P-TEFb, YB-1
Procedia PDF Downloads 1191468 A Non-Invasive Neonatal Jaundice Screening Device Measuring Bilirubin on Eyes
Authors: Li Shihao, Dieter Trau
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Bilirubin is a yellow substance that is made when the body breaks down old red blood cells. High levels of bilirubin can cause jaundice, a condition that makes the newborn's skin and the white part of the eyes look yellow. Jaundice is a serial-killer in developing countries in Southeast Asia such as Myanmar and most parts of Africa where jaundice screening is largely unavailable. Worldwide, 60% of newborns experience infant jaundice. One in ten will require therapy to prevent serious complications and lifelong neurologic sequelae. Limitations of current solutions: - Blood test: Blood tests are painful may largely unavailable in poor areas of developing countries, and also can be costly and unsafe due to the insufficient investment and lack of access to health care systems. - Transcutaneous jaundice-meter: 1) can only provide reliable results to caucasian newborns, due to skin pigmentations since current technologies measure bilirubin by the color of the skin. Basically, the darker the skin is, the harder to measure, 2) current jaundice meters are not affordable for most underdeveloped areas in Africa like Kenya and Togo, 3) fat tissue under the skin also influences the accuracy, which will give overestimated results, 4) current jaundice meters are not reliable after treatment (phototherapy) because bilirubin levels underneath the skin will be reduced first, while overall levels may be quite high. Thus, there is an urgent need for a low-cost non-invasive device, which can be effective not only for caucasian babies but also Asian and African newborns, to save lives at the most vulnerable time and prevent any complications like brain damage. Instead of measuring bilirubin on skin, we proposed a new method to do the measurement on the sclera, which can avoid the difference of skin pigmentations and ethnicities, due to the necessity for the sclera to be white regardless of racial background. This is a novel approach for measuring bilirubin by an optical method of light reflection off the white part of the eye. Moreover, the device is connected to a smart device, which can provide a user-friendly interface and the ability to record the clinical data continuously A disposable eye cap will be provided avoiding contamination and fixing the distance to the eye.Keywords: Jaundice, bilirubin, non-invasive, sclera
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