Search results for: optical polarization feedback
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3183

Search results for: optical polarization feedback

693 Effect of Al on Glancing Angle Deposition Synthesized In₂O₃ Nanocolumn for Photodetector Application

Authors: Chitralekha Ngangbam, Aniruddha Mondal, Naorem Khelchand Singh

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Aluminium (Al) doped In2O3 (Indium Oxide) nanocolumn array was synthesized by glancing angle deposition (GLAD) technique on Si (n-type) substrate for photodetector application. The sample was characterized by scanning electron microscopy (SEM). The average diameter of the nanocolumn was calculated from the top view of the SEM image and found to be ∼80 nm. The length of the nanocolumn (~500 nm) was calculated from cross sectional SEM image and it shows that the nanocolumns are perpendicular to the substrate. The EDX analysis confirmed the presence of Al (Aluminium), In (Indium), O (Oxygen) elements in the samples. The XRD patterns of the Al-doped In2O3 nanocolumn show the presence of different phases of the Al doped In2O3 nanocolumn i.e. (222) and (622). Three different peaks were observed from the PL analysis of Al doped In2O3 nanocolumn at 365 nm, 415 nm and 435 nm respectively. The peak at PL emission at 365 nm can be attributed to the near band gap transition of In2O3 whereas the peaks at 415 nm and 435 nm can be attributed to the trap state emissions due to oxygen vacancies and oxygen–indium vacancy centre in Al doped In2O3 nanocolumn. The current-voltage (I–V) characteristics of the Al doped In2O3 nanocolumn based detector was measured through the Au Schottky contact. The devices were then examined under the halogen light (20 W) illumination for photocurrent measurement. The Al-doped In2O3 nanocolumn based optical detector showed high conductivity and low turn on voltage at 0.69 V under white light illumination. A maximum photoresponsivity of 82 A/W at 380 nm was observed for the device. The device shows a high internal gain of ~267 at UV region (380 nm) and ∼127 at visible region (760 nm). Also the rise time and fall time for the device at 650 nm is 0.15 and 0.16 sec respectively which makes it suitable for fast response detector.

Keywords: glancing angle deposition, nanocolumn, semiconductor, photodetector, indium oxide

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692 Facile Fabrication of TiO₂NT/Fe₂O₃@Ag₂CO₃ Nanocomposite and Its Highly Efficient Visible Light Photocatalytic and Antibacterial Activity

Authors: Amal A. Al-Kahlawy, Heba H. El-Maghrabi

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Due to the increasing need to environment protection in real time need to energize new materials are under extensive investigations. Between others, TiO2 nanotubes (TNTs) nanocomposite with iron oxide and silver carbonate, are promising alternatives as high-efficiency visible light photocatalyst due to their unique properties and their superior charge transport properties. Our efforts in this domain aim the construction of novel nanocomposite of TiO2NT/Fe2O3@Ag2CO3. The structure, surface morphology, chemical composition and optical properties were characterized by X-ray diffraction (XRD), Raman, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and UV–vis diffuse reflectance spectroscopy (DRS). XRD results confirm the interaction of TiO2-NT with iron oxide. This novel nanocomposite shows remarkably enhanced performance for phenol compounds photodegradation. The experimental data shows a promising photocatalytic activity. In particular, a maximum value of 450 mg/g was removed within 60 min at solar light irradiation with degradation efficiency of 99.5%. The high photocatalytic activity of the nanocomposite is found to be related to the increased adsorption toward chemical species, enhanced light absorption and efficient charge separation and transfer. Finally, the designed TiO2NT/Fe2O3@Ag2CO3 nanocomposite has a great degree of sustainability and could has a potential application for the industrial treatment of wastewater containing toxic organic materials.

Keywords: nanocomposite, photocatalyst, solar energy, titanium dioxide nanotubes

Procedia PDF Downloads 216
691 Remote Sensing and GIS-Based Environmental Monitoring by Extracting Land Surface Temperature of Abbottabad, Pakistan

Authors: Malik Abid Hussain Khokhar, Muhammad Adnan Tahir, Hisham Bin Hafeez Awan

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Continuous environmental determinism and climatic change in the entire globe due to increasing land surface temperature (LST) has become a vital phenomenon nowadays. LST is accelerating because of increasing greenhouse gases in the environment which results of melting down ice caps, ice sheets and glaciers. It has not only worse effects on vegetation and water bodies of the region but has also severe impacts on monsoon areas in the form of capricious rainfall and monsoon failure extensive precipitation. Environment can be monitored with the help of various geographic information systems (GIS) based algorithms i.e. SC (Single), DA (Dual Angle), Mao, Sobrino and SW (Split Window). Estimation of LST is very much possible from digital image processing of satellite imagery. This paper will encompass extraction of LST of Abbottabad using SW technique of GIS and Remote Sensing over last ten years by means of Landsat 7 ETM+ (Environmental Thematic Mapper) and Landsat 8 vide their Thermal Infrared (TIR Sensor) and Optical Land Imager (OLI sensor less Landsat 7 ETM+) having 100 m TIR resolution and 30 m Spectral Resolutions. These sensors have two TIR bands each; their emissivity and spectral radiance will be used as input statistics in SW algorithm for LST extraction. Emissivity will be derived from Normalized Difference Vegetation Index (NDVI) threshold methods using 2-5 bands of OLI with the help of e-cognition software, and spectral radiance will be extracted TIR Bands (Band 10-11 and Band 6 of Landsat 7 ETM+). Accuracy of results will be evaluated by weather data as well. The successive research will have a significant role for all tires of governing bodies related to climate change departments.

Keywords: environment, Landsat 8, SW Algorithm, TIR

Procedia PDF Downloads 334
690 Investigation of Detectability of Orbital Objects/Debris in Geostationary Earth Orbit by Microwave Kinetic Inductance Detectors

Authors: Saeed Vahedikamal, Ian Hepburn

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Microwave Kinetic Inductance Detectors (MKIDs) are considered as one of the most promising photon detectors of the future in many Astronomical applications such as exoplanet detections. The MKID advantages stem from their single photon sensitivity (ranging from UV to optical and near infrared), photon energy resolution and high temporal capability (~microseconds). There has been substantial progress in the development of these detectors and MKIDs with Megapixel arrays is now possible. The unique capability of recording an incident photon and its energy (or wavelength) while also registering its time of arrival to within a microsecond enables an array of MKIDs to produce a four-dimensional data block of x, y, z and t comprising x, y spatial, z axis per pixel spectral and t axis per pixel which is temporal. This offers the possibility that the spectrum and brightness variation for any detected piece of space debris as a function of time might offer a unique identifier or fingerprint. Such a fingerprint signal from any object identified in multiple detections by different observers has the potential to determine the orbital features of the object and be used for their tracking. Modelling performed so far shows that with a 20 cm telescope located at an Astronomical observatory (e.g. La Palma, Canary Islands) we could detect sub cm objects at GEO. By considering a Lambertian sphere with a 10 % reflectivity (albedo of the Moon) we anticipate the following for a GEO object: 10 cm object imaged in a 1 second image capture; 1.2 cm object for a 70 second image integration or 0.65 cm object for a 4 minute image integration. We present details of our modelling and the potential instrument for a dedicated GEO surveillance system.

Keywords: space debris, orbital debris, detection system, observation, microwave kinetic inductance detectors, MKID

Procedia PDF Downloads 68
689 The Politics of Identity: A Longitudinal Study of the Sociopolitical Development of Education Leaders

Authors: Shelley Zion

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This study examines the longitudinal impact (10 years) of a course for education leaders designed to encourage the development of critical consciousness surrounding issues of equity, oppression, power, and privilege. The ability to resist and challenge oppression across social and cultural contexts can be acquired through the use of transformative pedagogies that create spaces that use the practice of exploration to make connections between pervasive structural and institutional practices and race and ethnicity. This study seeks to extend this understanding by exploring the longitudinal influence of participating in a course that utilizes transformative pedagogies, course materials, exercises, and activities to encourage the practice of exploration of student experiences with racial and ethnic discrimination with the end goal of providing them with the necessary knowledge and skills that foster their ability to resist and challenge oppression and discrimination -critical action- in their lives. To this end, we use the explanatory power of the theories of critical consciousness development, sociopolitical development, and social identity construction that view exploration as a crucial practice in understanding the role ethnic and racial differences play in creating opportunities or barriers in the lives of individuals. When educators use transformative pedagogies, they create a space where students collectively explore their experiences with racial and ethnic discrimination through course readings, in-class activities, and discussions. The end goal of this exploration is twofold: first, to encourage the student’s ability to understand how differences are identified, given meaning to, and used to position them in specific places and spaces in their world; second, to scaffold students’ ability to make connections between their individual and collective differences and particular institutional and structural practices that create opportunities or barriers in their lives. Studies have found the formal exploration of students’ individual and collective differences in relation to their experiences with racial and ethnic discrimination results in developing an understanding of the roles race and ethnicity play in their lives. To trace the role played by exploration in identity construction, we utilize an integrative approach to identity construction informed by multiple theoretical frameworks grounded in cultural studies, social psychology, and sociology that understand social-cultural, racial, and ethnic -identities as dynamic and ever-changing based on context-specific environments. Stuart Hall refers to this practice as taking “symbolic detours through the past” while reflecting on the different ways individuals have been positioned based on their roots (group membership) and also how they, in turn, chose to position themselves through collective sense-making of the various meanings their differences carried through the routes they have taken. The practice of exploration in the construction of ethnic-racial identities has been found to be beneficial to sociopolitical development.

Keywords: political polarization, civic participation, democracy, education

Procedia PDF Downloads 28
688 Effect of High Intensity Ultrasonic Treatment on the Micro Structure, Corrosion and Mechanical Behavior of ac4c Aluminium Alloy

Authors: A.Farrag Farrag, A. M. El-Aziz Abdel Aziz, W. Khlifa Khlifa

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Ultrasonic treatment is a promising process nowadays in the engineering field due to its high efficiency and it is a low-cost process. It enhances mechanical properties, corrosion resistance, and homogeneity of the microstructure. In this study, the effect of ultrasonic treatment and several casting conditions on microstructure, hardness and corrosion behavior of AC4C aluminum alloy was examined. Various ultrasonic treatments of the AC4C alloys were carried out to prepare billets for thixocasting process. Treatment temperatures varied from about 630oC and cooled down to under ultrasonic field. Treatment time was about 90s. A 600-watts ultrasonic system with 19.5 kHz and intensity of 170 W/cm2 was used. Billets were reheated to semisolid state and held for 5 minutes at 582 oC and temperatures (soaking) using high-frequency induction system, then thixocasted using a die casting machine. Microstructures of the thixocast parts were studied using optical and SEM microscopes. On the other hand, two samples were conventionally cast and poured at 634 oC and 750 oC. The microstructure showed a globular none dendritic grains for AC4C with the application of UST at 630-582 oC, Less dendritic grains when the sample was conventionally cast without the application of UST and poured at 624 oC and a fully dendritic microstructure When the sample was cast and poured at 750 oC without UST .The ultrasonic treatment during solidification proved that it has a positive influence on the microstructure as it produced the finest and globular grains thus it is expected to increase the mechanical properties of the alloy. Higher values of corrosion resistance and hardness were recorded for the ultrasound-treated sample in comparison to cast one.

Keywords: ultrasonic treatment, aluminum alloys, corrosion behaviour, mechanical behaviour, microstructure

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687 Electromechanical Reliability of ITO/Ag/ITO Multilayer Coated Pet Substrate for Optoelectronic Application

Authors: D. W. Mohammed, J. Bowen, S. N. Kukureka

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Successful design and fabrication of flexible devices for electrode components requires a low sheet resistance, high optical transmittance, high mechanical reliability. Indium tin oxide (ITO) film is currently the predominant transparent conductive oxide (TCO) film in potential applications such as flexible organic light- emitting diodes, flat-panel displays, solar cells, and thin film transistors (TFTs). However ITO films are too brittle and their resistivity is rather high in some cases compared with ITO/Ag/ ITO, and they cannot completely meet flexible optoelectronic device requirements. Therefore, in this work the mechanical properties of ITO /Ag/ITO multilayer film that deposited on Polyethylene terephthalate (PET) compared with the single layered ITO sample were investigated using bending fatigue, twisting fatigue and thermal cycling experiments. The electrical resistance was monitored during the application of mechanical and thermal loads to see the pattern of relationship between the load and the electrical continuity as a consequent of failure. Scanning electron microscopy and atomic force microscopy were used to provide surface characterization of the mechanically-tested samples. The effective embedment of the Ag layer between upper and lower ITO films led to metallic conductivity and superior flexibility to the single ITO electrode, due to the high failure strain of the ductile Ag layer. These results indicate that flexible ITO/Ag/ITO multilayer electrodes are a promising candidate for use as transparent conductor in flexible displays. They provided significantly reduced sheet resistance compared to ITO, and improved bending and twisting properties both as a function of radius, angle and thermal cycling.

Keywords: ITO/Ag/ITO multilayer, failure strain, mechanical properties, PET

Procedia PDF Downloads 277
686 Synthesis and Characterization of Chiral Dopant Based on Schiff's Base Structure

Authors: Hong-Min Kim, Da-Som Han, Myong-Hoon Lee

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CLCs (Cholesteric liquid crystals) draw tremendous interest due to their potential in various applications such as cholesteric color filters in LCD devices. CLC possesses helical molecular orientation which is induced by a chiral dopant molecules mixed with nematic liquid crystals. The efficiency of a chiral dopant is quantified by the HTP (helical twisting power). In this work, we designed and synthesized a series of new chiral dopants having a Schiff’s base imine structure with different alkyl chain lengths (butyl, hexyl and octyl) from chiral naphthyl amine by two-step reaction. The structures of new chiral dopants were confirmed by 1H-NMR and IR spectroscopy. The properties were investigated by DSC (differential scanning calorimetry calorimetry), POM (polarized optical microscopy) and UV-Vis spectrophotometer. These solid state chiral dopants showed excellent solubility in nematic LC (MLC-6845-000) higher than 17wt%. We prepared the CLC(Cholesteric Liquid Crystal) cell by mixing nematic LC (MLC-6845-000) with different concentrations of chiral dopants and injecting into the sandwich cell of 5μm cell gap with antiparallel alignment. The cholesteric liquid crystal phase was confirmed from POM, in which all the samples showed planar phase, a typical phase of the cholesteric liquid crystals. The HTP (helical twisting power) is one of the most important properties of CLC. We measured the HTP values from the UV-Vis transmittance spectra of CLC cells with varies chiral dopant concentration. The HTP values with different alkyl chains are as follows: butyl chiral dopant=29.8μm-1; hexyl chiral dopant= 31.8μm-1; octyl chiral dopant=27.7μm-1. We obtained the red, green and blue reflection color from CLC cells, which can be used as color filters in LCDs applications.

Keywords: cholesteric liquid crystal, color filter, display, HTP

Procedia PDF Downloads 237
685 Compact LWIR Borescope Sensor for Thermal Imaging of 2D Surface Temperature in Gas-Turbine Engines

Authors: Andy Zhang, Awnik Roy, Trevor B. Chen, Bibik Oleksandar, Subodh Adhikari, Paul S. Hsu

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The durability of a combustor in gas-turbine engines is a strong function of its component temperatures and requires good control of these temperatures. Since the temperature of combustion gases frequently exceeds the melting point of the combustion liner walls, an efficient air-cooling system with optimized flow rates of cooling air is significantly important to elongate the lifetime of liner walls. To determine the effectiveness of the air-cooling system, accurate two-dimensional (2D) surface temperature measurement of combustor liner walls is crucial for advanced engine development. Traditional diagnostic techniques for temperature measurement in this application include the rmocouples, thermal wall paints, pyrometry, and phosphors. They have shown some disadvantages, including being intrusive and affecting local flame/flow dynamics, potential flame quenching, and physical damages to instrumentation due to harsh environments inside the combustor and strong optical interference from strong combustion emission in UV-Mid IR wavelength. To overcome these drawbacks, a compact and small borescope long-wave-infrared (LWIR) sensor is developed to achieve 2D high-spatial resolution, high-fidelity thermal imaging of 2D surface temperature in gas-turbine engines, providing the desired engine component temperature distribution. The compactLWIRborescope sensor makes it feasible to promote the durability of a combustor in gas-turbine engines and, furthermore, to develop more advanced gas-turbine engines.

Keywords: borescope, engine, low-wave-infrared, sensor

Procedia PDF Downloads 100
684 Photocatalytic Hydrogen Production, Effect of Metal Particle Size and Their Electronic/Optical Properties on the Reaction

Authors: Hicham Idriss

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Hydrogen production from water is one of the most promising methods to secure renewable sources or vectors of energy for societies in general and for chemical industries in particular. At present over 90% of the total amount of hydrogen produced in the world is made from non-renewable fossil fuels (via methane reforming). There are many methods for producing hydrogen from water and these include reducible oxide materials (solar thermal production), combined PV/electrolysis, artificial photosynthesis and photocatalysis. The most promising of these processes is the one relying on photocatalysis; yet serious challenges are hindering its success so far. In order to make this process viable considerable improvement of the photon conversion is needed. Among the key studies that our group has been conducting in the last few years are those focusing on synergism between the semiconductor phases, photonic band gap materials, pn junctions, plasmonic resonance responses, charge transfer to metal cations, in addition to metal dispersion and band gap engineering. In this work results related to phase transformation of the anatase to rutile in the case of TiO2 (synergism), of Au and Ag dispersion (electron trapping and hydrogen-hydrogen recombination centers) as well as their plasmon resonance response (visible light conversion) are presented and discussed. It is found for example that synergism between the two common phases of TiO2 (anatase and rutile) is sensitive to the initial particle size. It is also found, in agreement with previous results, that the rate is very sensitive to the amount of metals (with similar particle size) on the surface unlike the case of thermal heterogeneous catalysis.

Keywords: photo-catalysis, hydrogen production, water splitting, plasmonic

Procedia PDF Downloads 224
683 Roof and Road Network Detection through Object Oriented SVM Approach Using Low Density LiDAR and Optical Imagery in Misamis Oriental, Philippines

Authors: Jigg L. Pelayo, Ricardo G. Villar, Einstine M. Opiso

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The advances of aerial laser scanning in the Philippines has open-up entire fields of research in remote sensing and machine vision aspire to provide accurate timely information for the government and the public. Rapid mapping of polygonal roads and roof boundaries is one of its utilization offering application to disaster risk reduction, mitigation and development. The study uses low density LiDAR data and high resolution aerial imagery through object-oriented approach considering the theoretical concept of data analysis subjected to machine learning algorithm in minimizing the constraints of feature extraction. Since separating one class from another in distinct regions of a multi-dimensional feature-space, non-trivial computing for fitting distribution were implemented to formulate the learned ideal hyperplane. Generating customized hybrid feature which were then used in improving the classifier findings. Supplemental algorithms for filtering and reshaping object features are develop in the rule set for enhancing the final product. Several advantages in terms of simplicity, applicability, and process transferability is noticeable in the methodology. The algorithm was tested in the different random locations of Misamis Oriental province in the Philippines demonstrating robust performance in the overall accuracy with greater than 89% and potential to semi-automation. The extracted results will become a vital requirement for decision makers, urban planners and even the commercial sector in various assessment processes.

Keywords: feature extraction, machine learning, OBIA, remote sensing

Procedia PDF Downloads 338
682 A Visual Analytics Tool for the Structural Health Monitoring of an Aircraft Panel

Authors: F. M. Pisano, M. Ciminello

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Aerospace, mechanical, and civil engineering infrastructures can take advantages from damage detection and identification strategies in terms of maintenance cost reduction and operational life improvements, as well for safety scopes. The challenge is to detect so called “barely visible impact damage” (BVID), due to low/medium energy impacts, that can progressively compromise the structure integrity. The occurrence of any local change in material properties, that can degrade the structure performance, is to be monitored using so called Structural Health Monitoring (SHM) systems, in charge of comparing the structure states before and after damage occurs. SHM seeks for any "anomalous" response collected by means of sensor networks and then analyzed using appropriate algorithms. Independently of the specific analysis approach adopted for structural damage detection and localization, textual reports, tables and graphs describing possible outlier coordinates and damage severity are usually provided as artifacts to be elaborated for information extraction about the current health conditions of the structure under investigation. Visual Analytics can support the processing of monitored measurements offering data navigation and exploration tools leveraging the native human capabilities of understanding images faster than texts and tables. Herein, a SHM system enrichment by integration of a Visual Analytics component is investigated. Analytical dashboards have been created by combining worksheets, so that a useful Visual Analytics tool is provided to structural analysts for exploring the structure health conditions examined by a Principal Component Analysis based algorithm.

Keywords: interactive dashboards, optical fibers, structural health monitoring, visual analytics

Procedia PDF Downloads 100
681 Chromosomal Damage in Human Lymphocytes by Ultraviolet Radiation

Authors: Felipe Osorio Ospina, Maria Adelaida Mejia Arango, Esteban Onésimo Vallejo Agudelo, Victoria Lucía Dávila Osorio, Natalia Vargas Grisales, Lina María Martínez Sanchez, Camilo Andrés Agudelo Vélez, Ángela Maria Londoño García, Isabel Cristina Ortiz Trujillo

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Excessive exposure to ultraviolet radiation, has shown to be a risk factor for photodamage, alteration of the immune mechanisms to recognize malignant cells and cutaneous pro-inflamatorios States and skin cancers. Objective: Identify the time of exposure to ultraviolet radiation for the production of chromosomal damage in human lymphocytes. Methodology: We conducted an in vitro study serial, in which samples were taken from heparinized blood of healthy people, who do not submit exposure to agents that could induce chromosomal alterations. The samples were cultured in RPMI-1640 medium containing 10% fetal bovine serum, penicillin and streptomycin antibiotic. Subsequently, they were grouped and exposed to ultraviolet light for 1 to 20 seconds. At the end of the treatments, cytology samples were prepared, and it was colored with Giemsa (5%). Reading was carried out in an optical microscope and 100 metaphases analysed by treatment for posting chromosomal alterations. Each treatment was conducted at three separate times and each became two replicas. Results: We only presented chromosomal alterations in lymphocytes exposed to UV for a groups 1 to 3 seconds (p<0.05). Conclusions: Exposure to ultraviolet radiation generates visible damage in chromosomes from human lymphocytes observed in light microscopy, the highest rates of injury was observed between two and three seconds, and above this value, the reduction in the number of mitotic cells was evident.

Keywords: ultraviolet rays, lymphocytes, chromosome breakpoints, photodamage

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680 Ultraviolet Radiation and Chromosomal Damage in Human Lymphocytes

Authors: Felipe Osorio Ospina, Maria Adelaida Mejia Arango, Esteban Onésimo Vallejo Agudelo, Victoria Lucía Dávila Osorio, Natalia Vargas Grisales, Lina María Martínez Sanchez, Camilo Andrés Agudelo Vélez, Ángela Maria Londoño García, Isabel Cristina Ortiz Trujillo

Abstract:

Excessive exposure to ultraviolet radiation, has shown to be a risk factor for photodamage, alteration of the immune mechanisms to recognize malignant cells and cutaneous pro-inflamatorios states and skin cancers. Objective: To identify the time of exposure to ultraviolet radiation for the production of chromosomal damage in human lymphocytes. Methodology: We conducted an in vitro study serial, in which samples were taken from the heparinized blood of healthy people, who do not submit exposure to agents that could induce chromosomal alterations. The samples were cultured in RPMI-1640 medium containing 10% fetal bovine serum, penicillin, and streptomycin antibiotic. Subsequently, they were grouped and exposed to ultraviolet light for 1 to 20 seconds. At the end of the treatments, cytology samples were prepared, and it was colored with Giemsa (5%). Reading was carried out in an optical microscope and 100 metaphases analysed by treatment for posting chromosomal alterations. Each treatment was conducted at three separate times and each became two replicas. Results: We only presented chromosomal alterations in lymphocytes exposed to UV for groups 1 to 3 seconds (p < 0.05). Conclusions: Exposure to ultraviolet radiation generates visible damage in chromosomes from human lymphocytes observed in light microscopy, the highest rates of injury was observed between two and three seconds, and above this value, the reduction in the number of mitotic cells was evident.

Keywords: chromosome breakpoints, lymphocytes, photodamage, ultraviolet rays

Procedia PDF Downloads 551
679 Dealing with Buckling Effect in Snorkel by Finite Element Analysis: A Life Enhancement Approach in CAS-OB Operation

Authors: Subodh Nath Patel, Raja Raman, Mananshi Adhikary, Jitendra Mathur, Sandip Bhattacharyya

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The composition adjustment by sealed argon bubbling–oxygen blowing (CAS-OB) process is a process designed for adjusting steel composition and temperature during secondary metallurgy. One of the equipment in the said process is a snorkel or bell, fixed to a movable bracket. Snorkel serves the purpose of feeding ferroalloys into the liquid metal simultaneously removing gases to the gas cleaning system through its port at its top. The bell-shaped snorkel consists of two parts. The upper part has an inside liner, and the lower part is lined on both side with high-alumina castable reinforced with 2% stainless steel needles. Both the parts are coupled with a flange bolt system. These flanges were found to get buckled during operation, and the gap was generating between them. This problem was chronic since its. It was expected to give a life of 80 heats, but it was failing within 45-50 heats. After every 25-30 heats, it had to be repaired by changing and/or tightening its nuts and bolts. Visual observation, microstructural analysis through optical microscopes and SEM, hardness measurement and thermal strain calculation were carried out to find out the root cause of this problem. The calculated thermal strain was compared with actual thermal strain; comparison of the two revealed that thermal strain was responsible for buckling. Finite element analysis (FEA) was carried out to reaffirm the effect temperature on the flanges. FEA was also used in the modification in the design of snorkel flange to accommodate thermal strain. Thermal insulation was also recommended which increased its life from 45 heats to 65 heats, impacting business process positively.

Keywords: CAS OB process, finite element analysis, snorkel, thermal strain

Procedia PDF Downloads 112
678 Plasma Spraying of 316 Stainless Steel on Aluminum and Investigation of Coat/Substrate Interface

Authors: P. Abachi, T. W. Coyle, P. S. Musavi Gharavi

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By applying coating onto a structural component, the corrosion and/or wear resistance requirements of the surface can be fulfilled. Since the layer adhesion of the coating influences the mechanical integrity of the coat/substrate interface during the service time, it should be examined accurately. At the present work, the tensile bonding strength of the 316 stainless steel plasma sprayed coating on aluminum substrate was determined by using tensile adhesion test, TAT, specimen. The interfacial fracture toughness was specified using four-point bend specimen containing a saw notch and modified chevron-notched short-bar (SB) specimen. The coating microstructure and fractured specimen surface were examined by using scanning electron- and optical-microscopy. The investigation of coated surface after tensile adhesion test indicates that the failure mechanism is mostly cohesive and rarely adhesive type. The calculated value of critical strain energy release rate proposes relatively good interface status. It seems that four-point bending test offers a potentially more sensitive means for evaluation of mechanical integrity of coating/substrate interfaces than is possible with the tensile test. The fracture toughness value reported for the modified chevron-notched short-bar specimen testing cannot be taken as absolute value because its calculation is based on the minimum stress intensity coefficient value which has been suggested for the fracture toughness determination of homogeneous parts in the ASTM E1304-97 standard. 

Keywords: bonding strength, four-point bend test, interfacial fracture toughness, modified chevron-notched short-bar specimen, plasma sprayed coating, tensile adhesion test

Procedia PDF Downloads 234
677 Creating a Multilevel ESL Learning Community for Adults

Authors: Gloria Chen

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When offering conventional level-appropriate ESL classes for adults is not feasible, a multilevel adult ESL class can be formed to benefit those who need to learn English for daily function. This paper examines the rationale, the process, the contents, and the outcomes of a multilevel ESL class for adults. The action research discusses a variety of assessments, lesson plans, teaching strategies that facilitate lifelong language learning. In small towns where adult ESL learners are only a handful, often advanced students and inexperienced students have to be placed in one class. Such class might not be viewed as desirable, but with on-going assessments, careful lesson plans, and purposeful strategies, a multilevel ESL class for adults can overcome the obstacles and help learners to reach a higher level of English proficiency. This research explores some hand-on strategies, such as group rotating, cooperative learning, and modifying textbook contents for practical purpose, and evaluate their effectiveness. The data collected in this research include Needs Assessment (beginning of class term), Mid-term Self-Assessment (5 months into class term), End-of-term Student Reflection (10 months into class), and End-of-term Assessment from the Instructor (10 months into class). A descriptive analysis of the data explains the practice of this particular learning community, and reveal the areas for improvement and enrichment. This research answers the following questions: (1) How do the assessments positively help both learners and instructors? (2) How do the learning strategies prepare students to become independent, life-long English learners? (3) How do materials, grouping, and class schedule enhance the learning? The result of the research contributes to the field of teaching and learning in language, not limited in English, by (a) examining strategies of conducting a multilevel adult class, (b) involving adult language learners with various backgrounds and learning styles for reflection and feedback, and (c) improving teaching and learning strategies upon research methods and results. One unique feature of this research is how students can work together with the instructor to form a learning community, seeking and exploring resources available to them, to become lifelong language learners.

Keywords: adult language learning, assessment, multilevel, teaching strategies

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676 Brand Tips of Thai Halal Products

Authors: Pibool Waijittragum

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The purpose of this research is to analyze the marketing strategies of Thai Halal products which related to the way of life for Thai Muslims. The expected benefit is the marketing strategy for brand building process for Halal products in Thailand. 4 elements of marketing strategies which necessary for the brand identity creation is the research framework: Consists of Attributes, Benefits, Values and Personality. The research methodology was applied using qualitative and quantitative; 19 marketing experts with dynamic roles in Thai consumer products were interviewed. In addition, a field survey of 122 Thai Muslims selected from 175 Muslim communities in Bangkok was studied. Data analysis will be according to 5 categories of Thai Halal product: 1) Meat 2) Vegetable and Fruits 3) Instant foods and Garnishing ingredient 4) Beverages, desserts and snacks 5) Hygienic daily products; such as soap, shampoo and body lotion. The results will explain some suitable representation in the marketing strategies of Thai Halal products as are: 1) Benefit; the characteristics of the product with its benefit. Consumers will purchase this product with the reason of; it is beneficial nutrients product, there are no toxic or chemical residues. Fresh and clean materials 2) Attribute; the exterior images that attract to consumer. Consumers will purchase this product with the reason of; there is a standard proof mark, food and drug secure proof mark and Halal products mark. Packaging and its materials should be draw attention. Use an attractive graphic. Use outstanding images of product, material or ingredients. 3) Value; the value of products that affect to consumers perception; it is healthy products. Accumulate quality of life. It is a product of expertise, manufacturing of research result. Consumers are important. It’s sincere, honest and reliable to all. 4) Personality; reflection of consumers thought. The personality feedback to them after they were consumes this product; they are health care persons. They are the rational person, moral person, justice person and thoughtful person like a progressive thinking.

Keywords: marketing strategies, product identity, branding, Thai Halal products

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675 Development of an Optimised, Automated Multidimensional Model for Supply Chains

Authors: Safaa H. Sindi, Michael Roe

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This project divides supply chain (SC) models into seven Eras, according to the evolution of the market’s needs throughout time. The five earliest Eras describe the emergence of supply chains, while the last two Eras are to be created. Research objectives: The aim is to generate the two latest Eras with their respective models that focus on the consumable goods. Era Six contains the Optimal Multidimensional Matrix (OMM) that incorporates most characteristics of the SC and allocates them into four quarters (Agile, Lean, Leagile, and Basic SC). This will help companies, especially (SMEs) plan their optimal SC route. Era Seven creates an Automated Multidimensional Model (AMM) which upgrades the matrix of Era six, as it accounts for all the supply chain factors (i.e. Offshoring, sourcing, risk) into an interactive system with Heuristic Learning that helps larger companies and industries to select the best SC model for their market. Methodologies: The data collection is based on a Fuzzy-Delphi study that analyses statements using Fuzzy Logic. The first round of Delphi study will contain statements (fuzzy rules) about the matrix of Era six. The second round of Delphi contains the feedback given from the first round and so on. Preliminary findings: both models are applicable, Matrix of Era six reduces the complexity of choosing the best SC model for SMEs by helping them identify the best strategy of Basic SC, Lean, Agile and Leagile SC; that’s tailored to their needs. The interactive heuristic learning in the AMM of Era seven will help mitigate error and aid large companies to identify and re-strategize the best SC model and distribution system for their market and commodity, hence increasing efficiency. Potential contributions to the literature: The problematic issue facing many companies is to decide which SC model or strategy to incorporate, due to the many models and definitions developed over the years. This research simplifies this by putting most definition in a template and most models in the Matrix of era six. This research is original as the division of SC into Eras, the Matrix of Era six (OMM) with Fuzzy-Delphi and Heuristic Learning in the AMM of Era seven provides a synergy of tools that were not combined before in the area of SC. Additionally the OMM of Era six is unique as it combines most characteristics of the SC, which is an original concept in itself.

Keywords: Leagile, automation, heuristic learning, supply chain models

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674 The Study of Platelet-Rich Plasma(PRP) on Wounds of OLEFT Rats Using Expression of MMP-2, MMP-9 mRNA

Authors: Ho Seong Shin

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Introduction: A research in relation to wound healing also showed that platelet-rich plasma (PRP) was effective on normal tissue regeneration. Nonetheless, there is no evidence that when platelet-rich plasma was applied on diabetic wound, it normalize diabetic wound healing process. In this study, we have analyzed matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) expression to know the effect of PRP on diabetic wounds using Reverse transcription-polymerase chain reaction (RT-PCR) of MMP-2, MMP-9 mRNA. Materials and Methods: Platelet-rich plasma (PRP) was prepared from blood of 6 rats. The whole 120-mL was added immediately to an anticoagulant. Citrate phosphonate dextrose(CPD) buffer (0.15 mg CPDmL) in a ratio of 1 mL of CPD buffer to 5 mL of blood. The blood was then centrifuged at 220g for 20minutes. The supernatant was saved to produce fibrin glue. The participate containing PRP was used for second centrifugation at 480g for 20 minutes. The pellet from the second centrifugation was saved and diluted with supernatant until the platelet concentration became 900,000/μL. Twenty male, 4week-old OLETF rats were underwent operation; each rat had two wounds created on left and right sides. The each wound of left side was treated with PRP gel, the wound of right side was treated with physiologic saline gauze. Results: RT-PCR analysis; The levels of MMP-2 mRNA in PRP applied tissues were positively related to postwounding days, whereas MMP-2 mRNA expression in saline-applied tissues remained in 5day after treatment. MMP-9 mRNA was undetectable in saline-applied tissues for either tissue, except 3day after treatment. Following PRP-applied tissues, MMP-9 mRNA expression was detected, with maximal expression being seen at third day. The levels of MMP-9 mRNA in PRP applied tissues were reported high intensity of optical density related to saline applied tissues.

Keywords: diabetes, MMP-2, MMP-9, OLETF, PRP, wound healing MMP-9

Procedia PDF Downloads 249
673 Electro-Optic Parameters of Ferroelectric Particles- Liquid Crystal Composites

Authors: T. D. Ibragimov, A. R. Imamaliyev, G. M. Bayramov

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Influence of barium titanate particles on electro-optic properties of liquid crystal 4-cyano-4′-pentylbiphenyl (5CB) with positive dielectric anisotropy and the liquid crystalline (LC) mixture Н-37 consisting of 4-methoxybezylidene-4'–butylaniline and 4-ethoxybezylidene-4'–butylaniline with negative dielectric anisotropy was investigated. It was shown that a presence of particles inside 5СВ and H-37 decreased the clearing temperature from 35.2 °С to 32.5°С and from 61.2 oC to 60.1oC, correspondingly. The threshold voltage of the Fredericksz effect became 0.3 V for the BaTiO3-5CB colloid while the beginning of this effect of the pure 5СВ was observed at 2.1 V. Threshold voltage of the Fredericksz effect increased from 2.8 V to up 3.1 V at additive of particles into H-37. A rise time of the BaTiO3-5CB colloid improved while a decay time worsened in comparison with the pure 5CB at all applied voltages. The inverse trends were observed for the H-37 matrix, namely, a rise time worsened and a decay time improved. Among other things, the effect of fast light modulation was studied at application of the rectangular impulse with direct bias to an electro-optical cell with the BaTiO3 particles+5CB and the pure 5CB. At this case, a rise time of the composite worsened, a decay time improved in comparison with the pure 5CB. The pecularities of electrohydrodynamic instability (EHDI) formation was also investigated into the composite with the H-37 matrix. It was found that the voltage of the EHDI formation decreased, a rise time increased and a decay time decreased in comparison with the pure H-37. First of all, experimental results are explained by appearance of local electric fields near the polarized ferroelectric particles at application of external electric field and an existence of the additional obstacles (particles) for movement of ions.

Keywords: liquid crystal, ferroelectric particles, composite, electro-optics

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672 Crab Shell Waste Chitosan-Based Thin Film for Acoustic Sensor Applications

Authors: Maydariana Ayuningtyas, Bambang Riyanto, Akhiruddin Maddu

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Industrial waste of crustacean shells, such as shrimp and crab, has been considered as one of the major issues contributing to environmental pollution. The waste processing mechanisms to form new, practical substances with added value have been developed. Chitosan, a derived matter from chitin, which is obtained from crab and shrimp shells, performs prodigiously in broad range applications. A chitosan composite-based diaphragm is a new inspiration in fiber optic acoustic sensor advancement. Elastic modulus, dynamic response, and sensitivity to acoustic wave of chitosan-based composite film contribute great potentials of organic-based sound-detecting material. The objective of this research was to develop chitosan diaphragm application in fiber optic microphone system. The formulation was conducted by blending 5% polyvinyl alcohol (PVA) solution with dissolved chitosan at 0%, 1% and 2% in 1:1 ratio, respectively. Composite diaphragms were characterized for the morphological and mechanical properties to predict the desired acoustic sensor sensitivity. The composite with 2% chitosan indicated optimum performance with 242.55 µm thickness, 67.9% relative humidity, and 29-76% light transmittance. The Young’s modulus of 2%-chitosan composite material was 4.89×104 N/m2, which generated the voltage amplitude of 0.013V and performed sensitivity of 3.28 mV/Pa at 1 kHz. Based on the results above, chitosan from crustacean shell waste can be considered as a viable alternative material for fiber optic acoustic sensor sensing pad development. Further, the research in chitosan utilisation is proposed as novel optical microphone development in anthropogenic noise controlling effort for environmental and biodiversity conservation.

Keywords: acoustic sensor, chitosan, composite, crab shell, diaphragm, waste utilisation

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671 Residential Satisfaction and Public Perception of Socialized Housing Projects in Davao City, Philippines

Authors: Micah Amor P. Yares

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Aside from the provision of adequate housing, the Philippine government faces the challenge of ensuring that the housing units provided conform to the Filipino’s ambition to self as manifested by owning a small house on a big lot. The study aimed to explore the levels of satisfaction of end-users and the public perception towards socialized housing in Davao City, Philippines. The residential satisfaction survey includes three types of respondents, which are end-users of single-detached, duplex and rowhouse socialized housing units. Respondents were asked to rate their level of satisfaction and perception to the following housing components: Dwelling Unit; Public Facilities; Social Environment; Neighborhood Facilities; Management Systems; and Acquisition and Financing. The data were subjected to Exploratory Factor Analysis to determine if variables can be grouped together, and Confirmatory Factor Analysis to measure if the model fits the construct. In determining which component affects the level of perception and satisfaction, a Multiple Linear Regression Analysis was employed. Lastly, an Individual Samples T-Test was performed to compare the levels of satisfaction and perception among respondents. Results revealed that residents of socialized housing were highly satisfied with their living conditions despite concerns on management systems, public and neighborhood facilities. Residents' satisfaction is primarily influenced by the Social Environment, Acquisition and Financing, and the Dwelling Unit. However, a significant difference in residential satisfaction level was observed among different types of housing with rowhouse residents recording the lowest satisfaction level compared to single-detached and duplex units. Moreover, the general public perceived Socialized housing as moderately satisfactory having the same determinant as the end-users aside from the Public Facilities. This study recommends revisiting the current Socialized Housing policies by considering the feedback from the end-users based on their lived experience and the public according to their perception.

Keywords: public perception, residential satisfaction, rowhouse, socialized housing

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670 Synthesis of Pyrimidine-Based Polymers Consist of 2-{4-[4,6-Bis-(4-Hexyl-Thiophen-2-yl)-Pyrimidin-2-yl]-Phenyl}-Thiazolo[5,4-B]Pyridine with Deep HOMO Level for Photovoltaics

Authors: Hyehyeon Lee, Jiwon Yu, Juwon Kim, Raquel Kristina Leoni Tumiar, Taewon Kim, Juae Kim, Hongsuk Suh

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Photovoltaics, which have many advantages in cost, easy processing, and light-weight, have attracted attention. We synthesized pyrimidine-based conjugated polymers with 2-{4-[4,6-bis-(4-hexyl-thiophen-2-yl)-pyrimidin-2-yl]-phenyl}-thiazolo[5,4-b]pyridine (pPTP) which have an ability of powerful electron withdrawing and introduced into the PSCs. By Stille polymerization, we designed the conjugated polymers, pPTPBDT-12, pPTPBDT-EH, pPTPBDTT-EH and pPTPTTI. The HOMO energy levels of four polymers (pPTPBDT-12, pPTPBDT-EH, pPTPBDTT-EH and pPTPTTI) were at -5.61 ~ -5.89 eV, their LUMO (Lowest Unoccupied Molecular Orbital) energy levels were at -3.95 ~ -4.09 eV. The device including pPTPBDT-12 and PC71BM (1:2) indicated a V_oc of 0.67 V, a J_sc of 1.33 mA/cm², and a fill factor (FF) of 0.25, giving a power conversion efficiency (PCE) of 0.23%. The device including pPTPBDT-EH and PC71BM (1:2) indicated a V_oc of 0.72 V, a J_sc of 2.56 mA/cm², and a fill factor (FF) of 0.30, giving a power conversion efficiency of 0.56%. The device including pPTPBDTT-EH and PC71BM (1:2) indicated a V_oc of 0.72 V, a J_sc of 3.61 mA/cm², and a fill factor (FF) of 0.29, giving a power conversion efficiency of 0.74%. The device including pPTPTTI and PC71BM (1:2) indicated a V_oc of 0.83 V, a J_sc of 4.41 mA/cm², and a fill factor (FF) of 0.31, giving a power conversion efficiency of 1.13%. Therefore, pPTPBDT-12, pPTPBDT-EH, pPTPBDTT-EH, and pPTPTTI were synthesized by Stille polymerization. And We find one of the best efficiency for these polymers, called pPTPTTI. Their optical properties were measured and the results show that pyrimidine-based polymers especially like pPTPTTI have a great promise to act as the donor of the active layer.

Keywords: polymer solar cells, pyrimidine-based polymers, photovoltaics, conjugated polymer

Procedia PDF Downloads 172
669 The Hydrotrope-Mediated, Low-Temperature, Aqueous Dissolution of Maize Starch

Authors: Jeroen Vinkx, Jan A. Delcour, Bart Goderis

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Complete aqueous dissolution of starch is notoriously difficult. A high-temperature autoclaving process is necessary, followed by cooling the solution below its boiling point. The cooled solution is inherently unstable over time. Gelation and retrogradation processes, along with aggregation-induced by undissolved starch remnants, result in starch precipitation. We recently observed the spontaneous gelatinization of native maize starch (MS) in aqueous sodium salicylate (NaSal) solutions at room temperature. A hydrotropic mode of solubilization is hypothesized. Differential scanning calorimetry (DSC) and polarized optical microscopy (POM) of starch dispersions in NaSal solution were used to demonstrate the room temperature gelatinization of MS at different concentrations of MS and NaSal. The DSC gelatinization peak shifts to lower temperatures, and the gelatinization enthalpy decreases with increasing NaSal concentration. POM images confirm the same trend through the disappearance of the ‘Maltese cross’ interference pattern of starch granules. The minimal NaSal concentration to induce complete room temperature dissolution of MS was found to be around 15-20 wt%. The MS content of the dispersion has little influence on the amount of NaSal needed to dissolve it. The effect of the NaSal solution on the MS molecular weight was checked with HPSEC. It is speculated that, because of its amphiphilic character, NaSal enhances the solubility of MS in water by association with the more hydrophobic MS moieties, much like urea, which has also been used to enhance starch dissolution in alkaline aqueous media. As such small molecules do not tend to form micelles in water, they are called hydrotropes rather than surfactants. A minimal hydrotrope concentration (MHC) is necessary for the hydrotropes to structure themselves in water, resulting in a higher solubility of MS. This is the case for the system MS/NaSal/H₂O. Further investigations into the putative hydrotropic dissolution mechanism are necessary.

Keywords: hydrotrope, dissolution, maize starch, sodium salicylate, gelatinization

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668 Creation and Implementation of A New Palliative Care Drug Chart, via A Closed-Loop Audit

Authors: Asfa Hussain, Chee Tang, Mien Nguyen

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Introduction: The safe usage of medications is dependent on clear, well-documented prescribing. Medical drug charts should be regularly checked to ensure that they are fit for purpose. Aims: The purpose of this study was to evaluate whether the Isabel Hospice drug charts were effective or prone to medical errors. The aim was to create a comprehensive palliative care drug chart in line with medico-legal guidelines and to minimise drug administration and prescription errors. Methodology: 50 medical drug charts were audited from March to April 2020, to assess whether they complied with medico-legal guidelines, in a hospice within East of England. Meetings were held with the larger multi-disciplinary team (MDT), including the pharmacists, nursing staff and doctors, to raise awareness of the issue. A preliminary drug chart was created, using the input from the wider MDT. The chart was revised and trialled over 15 times, and each time feedback from the MDT was incorporated into the subsequent template. In the midst of the COVID-19 pandemic in September 2020, the finalised drug chart was trialled. 50 new palliative drug charts were re-audited, to evaluate the changes made. Results: Prescribing and administration errors were high prior to the implementation of the new chart. This improved significantly after introducing the new drug charts, therefore improving patient safety and care. The percentage of inadequately documented allergies went down from 66% to 20% and incorrect oxygen prescription from 40% to 16%. The prescription drug-drug interactions decreased by 30%. Conclusion: It is vital to have clear standardised drug charts, in line with medico-legal standards, to allow ease of prescription and administration of medications and ensure optimum patient-centred care. This closed loop audit demonstrated significant improvement in documentation and prevention of possible fatal drug errors and interactions.

Keywords: palliative care, drug chart, medication errors, drug-drug interactions, COVID-19, patient safety

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667 Characterization and Evaluation of the Dissolution Increase of Molecular Solid Dispersions of Efavirenz

Authors: Leslie Raphael de M. Ferraz, Salvana Priscylla M. Costa, Tarcyla de A. Gomes, Giovanna Christinne R. M. Schver, Cristóvão R. da Silva, Magaly Andreza M. de Lyra, Danilo Augusto F. Fontes, Larissa A. Rolim, Amanda Carla Q. M. Vieira, Miracy M. de Albuquerque, Pedro J. Rolim-Neto

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Efavirenz (EFV) is a drug used as first-line treatment of AIDS. However, it has poor aqueous solubility and wettability, presenting problems in the gastrointestinal tract absorption and bioavailability. One of the most promising strategies to improve the solubility is the use of solid dispersions (SD). Therefore, this study aimed to characterize SD EFZ with the polymers: PVP-K30, PVPVA 64 and SOLUPLUS in order to find an optimal formulation to compose a future pharmaceutical product for AIDS therapy. Initially, Physical Mixtures (PM) and SD with the polymers were obtained containing 10, 20, 50 and 80% of drug (w/w) by the solvent method. The best formulation obtained between the SD was selected by in vitro dissolution test. Finally, the drug-carrier system chosen, in all ratios obtained, were analyzed by the following techniques: Differential Scanning Calorimetry (DSC), polarization microscopy, Scanning Electron Microscopy (SEM) and spectrophotometry of absorption in the region of infrared (IR). From the dissolution profiles of EFV, PM and SD, the values of area Under The Curve (AUC) were calculated. The data showed that the AUC of all PM is greater than the isolated EFV, this result is derived from the hydrophilic properties of the polymers thus favoring a decrease in surface tension between the drug and the dissolution medium. In adittion, this ensures an increasing of wettability of the drug. In parallel, it was found that SD whom had higher AUC values, were those who have the greatest amount of polymer (with only 10% drug). As the amount of drug increases, it was noticed that these results either decrease or are statistically similar. The AUC values of the SD using the three different polymers, followed this decreasing order: SD PVPVA 64-EFV 10% > SD PVP-K30-EFV 10% > SD Soluplus®-EFV 10%. The DSC curves of SD’s did not show the characteristic endothermic event of drug melt process, suggesting that the EFV was converted to its amorphous state. The analysis of polarized light microscopy showed significant birefringence of the PM’s, but this was not observed in films of SD’s, thus suggesting the conversion of the drug from the crystalline to the amorphous state. In electron micrographs of all PM, independently of the percentage of the drug, the crystal structure of EFV was clearly detectable. Moreover, electron micrographs of the SD with the two polymers in different ratios investigated, we observed the presence of particles with irregular size and morphology, also occurring an extensive change in the appearance of the polymer, not being possible to differentiate the two components. IR spectra of PM corresponds to the overlapping of polymer and EFV bands indicating thereby that there is no interaction between them, unlike the spectra of all SD that showed complete disappearance of the band related to the axial deformation of the NH group of EFV. Therefore, this study was able to obtain a suitable formulation to overcome the solubility limitations of the EFV, since SD PVPVA 64-EFZ 10% was chosen as the best system in delay crystallization of the prototype, reaching higher levels of super saturation.

Keywords: characterization, dissolution, Efavirenz, solid dispersions

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666 Real-Time Monitoring of Drinking Water Quality Using Advanced Devices

Authors: Amani Abdallah, Isam Shahrour

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The quality of drinking water is a major concern of public health. The control of this quality is generally performed in the laboratory, which requires a long time. This type of control is not adapted for accidental pollution from sudden events, which can have serious consequences on population health. Therefore, it is of major interest to develop real-time innovative solutions for the detection of accidental contamination in drinking water systems This paper presents researches conducted within the SunRise Demonstrator for ‘Smart and Sustainable Cities’ with a particular focus on the supervision of the water quality. This work aims at (i) implementing a smart water system in a large water network (Campus of the University Lille1) including innovative equipment for real-time detection of abnormal events, such as those related to the contamination of drinking water and (ii) develop a numerical modeling of the contamination diffusion in the water distribution system. The first step included verification of the water quality sensors and their effectiveness on a network prototype of 50m length. This part included the evaluation of the efficiency of these sensors in the detection both bacterial and chemical contamination events in drinking water distribution systems. An on-line optical sensor integral with a laboratory-scale distribution system (LDS) was shown to respond rapidly to changes in refractive index induced by injected loads of chemical (cadmium, mercury) and biological contaminations (Escherichia coli). All injected substances were detected by the sensor; the magnitude of the response depends on the type of contaminant introduced and it is proportional to the injected substance concentration.

Keywords: distribution system, drinking water, refraction index, sensor, real-time

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665 Modified Norhaya Upper Limp Elevation Sling-Quick Approach Ensuring Timely Limb Elevation

Authors: Prem, Norhaya, Vwrene C., Mohammad Harris A., Amarjit, Fazir M.

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Upper limb surgery is a common orthopedic procedure. After surgery, it is necessary to raise the patient's arm to reduce limb swelling and promote recovery. After an injury or surgery, swelling (edema) in the limbs is common. This swelling can be painful, cause stiffness, and affect movement and ability to do daily activities. One of the easiest ways to manage swelling is to elevate the swollen limb. The goal is to elevate the swollen limb slightly above the level of the heart. This helps the extra fluid move back towards the heart for circulation to the rest of the body. Conventional arm sling or pillows are usually placed under the arm to raise it, but in this way the arm cannot be fixed well and easily slide down, without ideal raising effect. Conventional arm sling need experience to tie the sling and this delay in the application process. To reduce the waiting time and cost, modified Norhaya upper limb elevation sling was designed and made readily available. The sling is made from calico fabric, readily available in the ward. Measurements of patients’ arm lengths are obtained, and fabric sizes are cut into the average arm lengths, as well as 1 size above and below. The cut calico fabric is then sewn together with thick sewing threads. Its application is easy and junior most staff or doctor will be able to apply it on patient. The time taken to set up the sling is also reduced. Feedback gathered from ground staff regarding ease of setting up the sling was tremendous and patient also feel comfort in the modified Norhaya sling. The device can freely adjust the raising height of the affected limb and effectively fix the affected limb to reduce its swelling, thus promoting recovery. This device is worthy to be clinically popularized and applied. The Modified Norhaya upper limb elevation sling is the quickest to set up and the delay in elevating the patient’s hand is significantly reduced. Moreover, it is reproducible and there is also significant cost savings.

Keywords: elevate, effective, sling, timely

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664 Investigation on Reducing the Bandgap in Nanocomposite Polymers by Doping

Authors: Sharvare Palwai, Padmaja Guggilla

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Smart materials, also called as responsive materials, undergo reversible physical or chemical changes in their properties as a consequence of small environmental variations. They can respond to a single or multiple stimuli such as stress, temperature, moist, electric or magnetic fields, light, or chemical compounds. Hence smart materials are the basis of many applications, including biosensors and transducers, particularly electroactive polymers. As the polymers exhibit good flexibility, high transparency, easy processing, and low cost, they would be promising for the sensor material. Polyvinylidene Fluoride (PVDF), being a ferroelectric polymer, exhibits piezoelectric and pyro electric properties. Pyroelectric materials convert heat directly into electricity, while piezoelectric materials convert mechanical energy into electricity. These characteristics of PVDF make it useful in biosensor devices and batteries. However, the influence of nanoparticle fillers such as Lithium Tantalate (LiTaO₃/LT), Potassium Niobate (KNbO₃/PN), and Zinc Titanate (ZnTiO₃/ZT) in polymer films will be studied comprehensively. Developing advanced and cost-effective biosensors is pivotal to foresee the fullest potential of polymer based wireless sensor networks, which will further enable new types of self-powered applications. Finally, nanocomposites films with best set of properties; the sensory elements will be designed and tested for their performance as electric generators under laboratory conditions. By characterizing the materials for their optical properties and investigate the effects of doping on the bandgap energies, the science in the next-generation biosensor technologies can be advanced.

Keywords: polyvinylidene fluoride, PVDF, lithium tantalate, potassium niobate, zinc titanate

Procedia PDF Downloads 105