Search results for: enhanced oil recovery
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4399

Search results for: enhanced oil recovery

3559 The Effects of Varying Nutrient Conditions on Hydrogen Production in PGR5 Deficient C. Reinhardtii Mutants

Authors: Samuel Mejorado

Abstract:

C. Reinahrdtii serves as one of the most promising organisms from which to obtain biological hydrogen. However, its production catalyst, [FeFe]-hydrogenase, is largely inhibited by the presence of oxygen. In recent years, researchers have identified a Proton Gradient Regulation 5 (PGR5) deficient mutant, which shows enhanced respiration and lower accumulations of oxygen within the system. In this research, we investigated the effects of varying nutrient conditions on PGR5 mutants' ability to produce hydrogen. After growing PGR5 mutants in varying nutrient conditions under 55W fluorescent lamps at 30℃ with constant stirring at 200 rpm, a common water displacement method was utilized to obtain a definitive volumetric reading of hydrogen produced by these mutants over a period of 12 days. After the trials, statistical t-tests and ANOVAs were performed to better determine the effect which nutrient conditions have on PGR5 mutants' ability to produce hydrogen. In this, we report that conditions of sulfur deprivation most optimally enhanced hydrogen production within these mutants, with groups grown under these conditions demonstrating the highest production capacity over the entire 12-day period. Similarly, it was found that when grown under conditions of nitrogen deprivation, a favorable shift towards carbon fixation and overall lipid/starch metabolism was observed. Overall, these results demonstrate that PGR5-deficient mutants stand as a promising source of biohydrogen when grown under conditions of sulfur deprivation. To date, photochemical characteristics of [FeFe]-hydrogenase in these mutants have yet to be investigated under conditions of sulfur deprivation.

Keywords: biofuel, biohydrogen, [FeFe]-hydrogenase, algal biofuel

Procedia PDF Downloads 139
3558 Students' ExperiEnce Enhancement Through Simulaton. A Process Flow in Logistics and Transportation Field

Authors: Nizamuddin Zainuddin, Adam Mohd Saifudin, Ahmad Yusni Bahaudin, Mohd Hanizan Zalazilah, Roslan Jamaluddin

Abstract:

Students’ enhanced experience through simulation is a crucial factor that brings reality to the classroom. The enhanced experience is all about developing, enriching and applications of a generic process flow in the field of logistics and transportations. As educational technology has improved, the effective use of simulations has greatly increased to the point where simulations should be considered a valuable, mainstream pedagogical tool. Additionally, in this era of ongoing (some say never-ending) assessment, simulations offer a rich resource for objective measurement and comparisons. Simulation is not just another in the long line of passing fads (or short-term opportunities) in educational technology. It is rather a real key to helping our students understand the world. It is a way for students to acquire experience about how things and systems in the world behave and react, without actually touching them. In short, it is about interactive pretending. Simulation is all about representing the real world which includes grasping the complex issues and solving intricate problems. Therefore, it is crucial before stimulate the real process of inbound and outbound logistics and transportation a generic process flow shall be developed. The paper will be focusing on the validization of the process flow by looking at the inputs gains from the sample. The sampling of the study focuses on multi-national and local manufacturing companies, third party companies (3PL) and government agency, which are selected in Peninsular Malaysia. A simulation flow chart was proposed in the study that will be the generic flow in logistics and transportation. A qualitative approach was mainly conducted to gather data in the study. It was found out from the study that the systems used in the process of outbound and inbound are System Application Products (SAP) and Material Requirement Planning (MRP). Furthermore there were some companies using Enterprises Resources Planning (ERP) and Electronic Data Interchange (EDI) as part of the Suppliers Own Inventories (SOI) networking as a result of globalized business between one countries to another. Computerized documentations and transactions were all mandatory requirement by the Royal Custom and Excise Department. The generic process flow will be the basis of developing a simulation program that shall be used in the classroom with the objective of further enhanced the students’ learning experience. Thus it will contributes to the body of knowledge on the enrichment of the student’s employability and also shall be one of the way to train new workers in the logistics and transportation filed.

Keywords: enhancement, simulation, process flow, logistics, transportation

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3557 Anethum graveolens Prevents Liver and Kidney Injury, Oxidative Stress and Inflammation in Mice Exposed to Nicotine Perinatally

Authors: Saleh N. Maodaa

Abstract:

Perinatal exposure to nicotine imbalances the redox status in newborns. This study investigated the effect of Anethum graveolens (dill) extract on oxidative stress and tissue injury in the liver and kidney of mice newborns exposed to nicotine perinatally. Pregnant mice received nicotine (0.25 mg/kg) on gestational day 12 to day 5 after birth and/or A. graveolens extract on a gestational day 1 to day 15 after birth. Newborn mice exposed to nicotine showed multiple histopathological alterations in the kidney and liver, including inflammatory cell infiltration and degenerative changes. Nicotine exposure increased hepatic and renal reactive oxygen species (ROS), lipid peroxidation, tumor necrosis factor (TNF-_), interleukin-6 (IL-6), and inducible nitric oxide synthase (iNOS) (p < 0.001), and decreased antioxidant defenses (p < 0.001). A. graveolens supplementation significantly prevented liver and kidney injury, suppressed ROS generation (p < 0.001), lipid peroxidation (p < 0.001), and inflammatory response (p < 0.001), and enhanced antioxidant defenses. In addition, A. graveolens upregulated hepatic and renal Nrf2 and HO-1 mRNA and increased HO-1 activity in normal and nicotine-exposed mice. In conclusion, A. graveolens protects against perinatal nicotine-induced oxidative stress, inflammation, and tissue injury in the liver and kidney of newborn mice. A. graveolens upregulated hepatic and renal Nrf2/HO-1 signaling and enhanced antioxidant defenses in mice.

Keywords: dill, oxidative stress, cytokines, nicotine

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3556 Recycling Broken Photovoltaic Cells into Anodes for Lithium-Ion Batteries Using Open-Source 3D Printing

Authors: Maryam Mottaghi, Joshua M. Pearce

Abstract:

The increasing volume of end-of-life photovoltaic (PV) cells presents a significant environmental challenge and offers an opportunity for resource recovery. This work explores the use of broken silicon PV cells as a sustainable source of silicon for the fabrication of anodes in lithium-ion (Li-ion) batteries. An open-source toolchain provides a low-cost and accessible method for 3D printing anode composites. The silicon used in PV cells has already undergone energy-intensive purification and processing, which enhances its reuse in batteries as a more resource-efficient approach. While silicon is abundant and offers potential for high-capacity anodes, it faces challenges such as low conductivity and significant volume changes during cycling, which can lead to mechanical degradation and reduced battery performance. In this work, silicon PV waste is first ground into particles smaller than 50 microns using an open-source ball mill. The silicon particles mix with a UV-curable resin through an open-source bottle roller to form a printable slurry. This slurry is used to fabricate an acrylate-silicon composite via stereolithography (SLA) 3D printing. SLA 3D printing offers the advantage of high precision and the ability to create complex geometries, which can enhance the performance of the anode. The printed parts are then pyrolyzed in an inert nitrogen atmosphere, which burns away the volatile components of the resin and leaves behind a carbon residue that enhances conductivity and helps alleviate silicon volume expansion during cycling. The results demonstrate the feasibility of using broken solar cell anodes in batteries. This approach is a promising candidate for advancing recycling solutions. Additionally, the use of open-source toolchain promotes resource recovery and shows potential for future developments in circular economy within energy storage.

Keywords: recycling, silicon anode, Li-ion battery, 3D printing

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3555 Genetic Instabilities in Marine Bivalve Following Benzo(α)pyrene Exposure: Utilization of Combined Random Amplified Polymorphic DNA and Comet Assay

Authors: Mengjie Qu, Yi Wang, Jiawei Ding, Siyu Chen, Yanan Di

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Marine ecosystem is facing intensified multiple stresses caused by environmental contaminants from human activities. Xenobiotics, such as benzo(α)pyrene (BaP) have been discharged into marine environment and cause hazardous impacts on both marine organisms and human beings. As a filter-feeder, marine mussels, Mytilus spp., has been extensively used to monitor the marine environment. However, their genomic alterations induced by such xenobiotics are still kept unknown. In the present study, gills, as the first defense barrier in mussels, were selected to evaluate the genetic instability alterations induced by the exposure to BaP both in vivo and in vitro. Both random amplified polymorphic DNA (RAPD) assay and comet assay were applied as the rapid tools to assess the environmental stresses due to their low money- and time-consumption. All mussels were identified to be the single species of Mytilus coruscus before used in BaP exposure at the concentration of 56 μg/l for 1 & 3 days (in vivo exposure) or 1 & 3 hours (in vitro). Both RAPD and comet assay results were showed significantly increased genomic instability with time-specific altering pattern. After the recovery period in 'in vivo' exposure, the genomic status was as same as control condition. However, the relative higher genomic instabilities were still observed in gill cells after the recovery from in vitro exposure condition. Different repair mechanisms or signaling pathway might be involved in the isolated gill cells in the comparison with intact tissues. The study provides the robust and rapid techniques to exam the genomic stability in marine organisms in response to marine environmental changes and provide basic information for further mechanism research in stress responses in marine organisms.

Keywords: genotoxic impacts, in vivo/vitro exposure, marine mussels, RAPD and comet assay

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3554 Inverse Scattering for a Second-Order Discrete System via Transmission Eigenvalues

Authors: Abdon Choque-Rivero

Abstract:

The Jacobi system with the Dirichlet boundary condition is considered on a half-line lattice when the coefficients are real valued. The inverse problem of recovery of the coefficients from various data sets containing the so-called transmission eigenvalues is analyzed. The Marchenko method is utilized to solve the corresponding inverse problem.

Keywords: inverse scattering, discrete system, transmission eigenvalues, Marchenko method

Procedia PDF Downloads 141
3553 An Efficient Aptamer-Based Biosensor Developed via Irreversible Pi-Pi Functionalisation of Graphene/Zinc Oxide Nanocomposite

Authors: Sze Shin Low, Michelle T. T. Tan, Poi Sim Khiew, Hwei-San Loh

Abstract:

An efficient graphene/zinc oxide (PSE-G/ZnO) platform based on pi-pi stacking, non-covalent interactions for the development of aptamer-based biosensor was presented in this study. As a proof of concept, the DNA recognition capability of the as-developed PSE-G/ZnO enhanced aptamer-based biosensor was evaluated using Coconut Cadang-cadang viroid disease (CCCVd). The G/ZnO nanocomposite was synthesised via a simple, green and efficient approach. The pristine graphene was produced through a single step exfoliation of graphite in sonochemical alcohol-water treatment while the zinc nitrate hexahydrate was mixed with the graphene and subjected to low temperature hydrothermal growth. The developed facile, environmental friendly method provided safer synthesis procedure by eliminating the need of harsh reducing chemicals and high temperature. The as-prepared nanocomposite was characterised by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) to evaluate its crystallinity, morphology and purity. Electrochemical impedance spectroscopy (EIS) was employed for the detection of CCCVd sequence with the use of potassium ferricyanide (K3[Fe(CN)6]). Recognition of the RNA analytes was achieved via the significant increase in resistivity for the double stranded DNA, as compared to single-stranded DNA. The PSE-G/ZnO enhanced aptamer-based biosensor exhibited higher sensitivity than the bare biosensor, attributing to the synergistic effect of high electrical conductivity of graphene and good electroactive property of ZnO.

Keywords: aptamer-based biosensor, graphene/zinc oxide nanocomposite, green synthesis, screen printed carbon electrode

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3552 Valorization of Sargassum: Use of Twin-Screw Extrusion to Produce Biomolecules and Biomaterials

Authors: Bauta J., Raynaud C., Vaca-Medina G., Simon V., Roully A., Vandenbossche V.

Abstract:

Sargassum is a brown algae, originally found in the Sargasso Sea, located in the Caribbean region and the Gulf of Mexico. The flow of Sargassum is becoming a critical environmental problem all over the Caribbean islands particularly. In Guadeloupe alone, around 80,000 tons of seaweed are stranded during the season. Since the appearance of the first waves of Sargassum algae, several measures have been taken to collect them to keep the beaches clean. Nevertheless, 90% of the collected algae are currently stored without recovery. The lack of research initiative demands a more in-depth exploration of Sargassum algae chemistry, targeted towards added value applications and their development. In this context, the aim of the study was to develop a biorefinery process to valorize Sargassum as a source of bioactive natural substances and as raw material to produce biomaterials simultaneously. The technology used was the twin-screw extrusion, which allows to achieve continuously in the same machine different unit fractionation operations. After the identification of the molecules of interest in Sargassum algae, different operating conditions of thermo-mechanical treatment were applied in a twin-screw extruder. The nature of the solvent, the configuration of the extruder, the screw profile, and the temperature profile were studied in order to fractionate the algal biomass and to allow the recovery of a bioactive liquid fraction of interest and a solid residue suitable for the production of biomaterials. Each bioactive liquid fraction was characterized and strategic ways of adding value were proposed. In parallel, the possibility of using the solid residue to produce biomaterials was studied by setting up Dynamic Vapour Sorption (DVS) and basic Pressure-Volume-Temperature (PVT) analyses. The solid residue was molded by compression cooking. The obtained materials were finally characterized mechanically. The results obtained were very comforting and gave some perspectives to find an interesting valorization for the Sargassum algae.

Keywords: seaweeds, twin-screw extrusion, fractionation, bioactive compounds, biomaterials, biomass

Procedia PDF Downloads 123
3551 Reverse Logistics End of Life Products Acquisition and Sorting

Authors: Badli Shah Mohd Yusoff, Khairur Rijal Jamaludin, Rozetta Dollah

Abstract:

The emerging of reverse logistics and product recovery management is an important concept in reconciling economic and environmental objectives through recapturing values of the end of life product returns. End of life products contains valuable modules, parts, residues and materials that can create value if recovered efficiently. The main objective of this study is to explore and develop a model to recover as much of the economic value as reasonably possible to find the optimality of return acquisition and sorting to meet demand and maximize profits over time. In this study, the benefits that can be obtained for remanufacturer is to develop demand forecasting of used products in the future with uncertainty of returns and quality of products. Formulated based on a generic disassembly tree, the proposed model focused on three reverse logistics activity, namely refurbish, remanufacture and disposal incorporating all plausible means quality levels of the returns. While stricter sorting policy, constitute to the decrease amount of products to be refurbished or remanufactured and increases the level of discarded products. Numerical experiments carried out to investigate the characteristics and behaviour of the proposed model with mathematical programming model using Lingo 16.0 for medium-term planning of return acquisition, disassembly (refurbish or remanufacture) and disposal activities. Moreover, the model seeks an analysis a number of decisions relating to trade off management system to maximize revenue from the collection of use products reverse logistics services through refurbish and remanufacture recovery options. The results showed that full utilization in the sorting process leads the system to obtain less quantity from acquisition with minimal overall cost. Further, sensitivity analysis provides a range of possible scenarios to consider in optimizing the overall cost of refurbished and remanufactured products.

Keywords: core acquisition, end of life, reverse logistics, quality uncertainty

Procedia PDF Downloads 299
3550 Using Human-Centred Service Design and Partnerships as a Model to Promote Cross-Sector Social Responsibility in Disaster Resilience: An Australian Case Study

Authors: Keith Diamond, Tracy Collier, Ciara Sterling, Ben Kraal

Abstract:

The increased frequency and intensity of disaster events in the Asia-Pacific region is likely to require organisations to better understand how their initiatives, and the support they provide to their customers, intersect with other organisations aiming to support communities in achieving disaster resilience. While there is a growing awareness that disaster response and recovery rebuild programmes need to adapt to more integrated, community-led approaches, there is often a discrepancy between how programmes intend to work and how they are collectively experienced in the community, creating undesired effects on community resilience. Following Australia’s North Queensland Monsoon Disaster of 2019, this research set out to understand and evaluate how the service and support ecosystem impacted on the local community’s experience and influenced their ability to respond and recover. The purpose of this initiative was to identify actionable, cross-sector, people-centered improvements that support communities to recover and thrive when faced with disaster. The challenge arose as a group of organisations, including utility providers, banks, insurers, and community organisations, acknowledged that improving their own services would have limited impact on community wellbeing unless the other services people need are also improved and aligned. The research applied human-centred service design methods, typically applied to single products or services, to design a new way to understand a whole-of-community journey. Phase 1 of the research conducted deep contextual interviews with residents and small business owners impacted by the North Queensland Monsoon and qualitative data was analysed to produce community journey maps that detailed how individuals navigated essential services, such as accommodation, finance, health, and community. Phase 2 conducted interviews and focus groups with frontline workers who represented industries that provided essential services to assist the community. Data from Phase 1 and Phase 2 of the research was analysed and combined to generate a systems map that visualised the positive and negative impacts that occurred across the disaster response and recovery service ecosystem. Insights gained from the research has catalysed collective action to address future Australian disaster events. The case study outlines a transformative way for sectors and industries to rethink their corporate social responsibility activities towards a cross-sector partnership model that shares responsibility and approaches disaster response and recovery as a single service that can be designed to meet the needs of communities.

Keywords: corporate social responsibility, cross sector partnerships, disaster resilience, human-centred design, service design, systems change

Procedia PDF Downloads 150
3549 Enhanced Mechanical Properties and Corrosion Resistance of Fe-Based Thin Film Metallic Glasses via Pulsed Laser Deposition

Authors: Ali Obeydavi, Majid Rahimi

Abstract:

This study explores the synthesis and characterization of Fe-Cr-Mo-Co-C-B-Si thin film metallic glasses fabricated using the pulsed laser deposition (PLD) technique on silicon wafer and 304 stainless steel substrates. it systematically varied the laser pulse numbers (20,000; 30,000; 40,000) and energies (130, 165, 190 mJ) to investigate their effects on the microstructural, mechanical, and corrosion properties of the deposited films. Comprehensive characterization techniques, including grazing incidence X-ray diffraction, field emission scanning electron microscopy, atomic force microscopy, and transmission electron microscopy with selected area electron diffraction, were utilized to assess the amorphous structure and surface morphology. Results indicated that increased pulse numbers and laser energies led to enhanced deposition rates and film thicknesses. Nanoindentation tests demonstrated that the hardness and elastic modulus of the amorphous thin films significantly surpassed those of the 304 stainless steel substrate. Additionally, electrochemical polarization and impedance spectroscopy revealed that the Fe-based metallic glass coatings exhibited superior corrosion resistance compared to the stainless steel substrate. The observed improvements in mechanical and corrosion properties are attributed to the unique amorphous structure achieved through the PLD process, highlighting the potential of these materials for protective coatings in aggressive environments.

Keywords: thin film metallic glasses, pulsed laser deposition, mechanical properties, corrosion resistance

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3548 The Impact of Professional Development in the Area of Technology Enhanced Learning on Higher Education Teaching Practices Across Atlantic Technological University - Research Methodology and Preliminary Findings

Authors: Annette Cosgrove, Carina Ginty, Tony Hall, Cornelia Connolly

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The objectives of this research study is to examine the impact of professional development in Technology Enhanced Learning (TEL) and the digitization of learning in teaching communities across multiple higher education sites in the ATU (Atlantic Technological University *) ( 2020-2025), including the proposal of an evidence-based digital teaching model for use in a future pandemic. The research strategy undertaken for this study is a multi-site study using mixed methods. Qualitative & quantitative methods are being used in the study to collect data. A pilot study was carried out initially, feedback was collected and the research instrument was edited to reflect this feedback before being administered. The purpose of the staff questionnaire is to evaluate the impact of professional development in the area of TEL, and to capture the practitioner's views on the perceived impact on their teaching practice in the higher education sector across ATU (West of Ireland – 5 Higher education locations ). The phenomenon being explored is ‘ the impact of professional development in the area of technology-enhanced learning and on teaching practice in a higher education institution. The research methodology chosen for this study is an Action based Research Study. The researcher has chosen this approach as it is a prime strategy for developing educational theory and enhancing educational practice. This study includes quantitative and qualitative methods to elicit data that will quantify the impact that continuous professional development in the area of digital teaching practice and technologies has on the practitioner’s teaching practice in higher education. The research instruments/data collection tools for this study include a lecturer survey with a targeted TEL Practice group ( Pre and post covid experience) and semi-structured interviews with lecturers. This research is currently being conducted across the ATU multi-site campus and targeting Higher education lecturers that have completed formal CPD in the area of digital teaching. ATU, a West of Ireland university, is the focus of the study. The research questionnaire has been deployed, with 75 respondents to date across the ATU - the primary questionnaire and semi-formal interviews are ongoing currently – the purpose being to evaluate the impact of formal professional development in the area of TEL and its perceived impact on the practitioners teaching practice in the area of digital teaching and learning. This paper will present initial findings, reflections and data from this ongoing research study.

Keywords: TEL, technology, digital, education

Procedia PDF Downloads 76
3547 An Enhanced Approach in Validating Analytical Methods Using Tolerance-Based Design of Experiments (DoE)

Authors: Gule Teri

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The effective validation of analytical methods forms a crucial component of pharmaceutical manufacturing. However, traditional validation techniques can occasionally fail to fully account for inherent variations within datasets, which may result in inconsistent outcomes. This deficiency in validation accuracy is particularly noticeable when quantifying low concentrations of active pharmaceutical ingredients (APIs), excipients, or impurities, introducing a risk to the reliability of the results and, subsequently, the safety and effectiveness of the pharmaceutical products. In response to this challenge, we introduce an enhanced, tolerance-based Design of Experiments (DoE) approach for the validation of analytical methods. This approach distinctly measures variability with reference to tolerance or design margins, enhancing the precision and trustworthiness of the results. This method provides a systematic, statistically grounded validation technique that improves the truthfulness of results. It offers an essential tool for industry professionals aiming to guarantee the accuracy of their measurements, particularly for low-concentration components. By incorporating this innovative method, pharmaceutical manufacturers can substantially advance their validation processes, subsequently improving the overall quality and safety of their products. This paper delves deeper into the development, application, and advantages of this tolerance-based DoE approach and demonstrates its effectiveness using High-Performance Liquid Chromatography (HPLC) data for verification. This paper also discusses the potential implications and future applications of this method in enhancing pharmaceutical manufacturing practices and outcomes.

Keywords: tolerance-based design, design of experiments, analytical method validation, quality control, biopharmaceutical manufacturing

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3546 Internal Power Recovery in Cryogenic Cooling Plants, Part II: Compressor Development

Authors: Ambra Giovannelli, Erika Maria Archilei

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The electrical power consumption related to refrigeration systems is evaluated to be in the order of 15% of the total electricity consumption worldwide. For this reason, in the last years several energy saving techniques have been suggested to reduce the power demand of refrigeration and air conditioning plants. The research work deals with the development of an innovative internal power recovery system for industrial cryogenic cooling plants. Such system is based on a Compressor-Expander Group (CEG). Both the expander and the compressor have been designed starting from automotive turbocharging components, strongly modified to take refrigerant fluid properties and specific system requirements into consideration. A preliminary choice of the machines (radial compressors and expanders) among existing components available on the market was realised according to the rules of the similarity theory. Once the expander was selected, it was strongly modified and performance verified by means of steady-state 3D CFD simulations. This paper focuses the attention on the development of the second CEG main component: the compressor. Once the preliminary selection has been done, the compressor geometry has been modified to take the new boundary conditions into account. In particular, the impeller has been machined to address the required total enthalpy increase. Such evaluation has been carried out by means of a simplified 1D model. Moreover, a vaneless diffuser has been added, modifying the shape of casing rear and front disks. To verify the performance of the modified compressor geometry and suggest improvements, a numerical fluid dynamic model has been set up and the commercial Ansys-CFX software has been used to perform steady-state 3D simulations. In this work, all the numerical results will be shown, highlighting critical aspects and suggesting further developments to increase compressor performance and flexibility.

Keywords: vapour compression systems, energy saving, refrigeration plant, organic fluids, centrifugal compressor

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3545 Encapsulation of Probiotic Bacteria in Complex Coacervates

Authors: L. A. Bosnea, T. Moschakis, C. Biliaderis

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Two probiotic strains of Lactobacillus paracasei subsp. paracasei (E6) and Lactobacillus paraplantarum (B1), isolated from traditional Greek dairy products, were microencapsulated by complex coacervation using whey protein isolate (WPI, 3% w/v) and gum arabic (GA, 3% w/v) solutions mixed at different polymer ratio (1:1, 2:1 and 4:1). The effect of total biopolymer concentration on cell viability was assessed using WPI and GA solutions of 1, 3 and 6% w/v at a constant ratio of 2:1. Also, several parameters were examined for optimization of the microcapsule formation, such as inoculum concentration and the effect of ionic strength. The viability of the bacterial cells during heat treatment and under simulated gut conditions was also evaluated. Among the different WPI/GA weight ratios tested (1:1, 2:1, and 4:1), the highest survival rate was observed for the coacervate structures made with the ratio of 2:1. The protection efficiency at low pH values is influenced by both concentration and the ratio of the added biopolymers. Moreover, the inoculum concentration seems to affect the efficiency of microcapsules to entrap the bacterial cells since an optimum level was noted at less than 8 log cfu/ml. Generally, entrapment of lactobacilli in the complex coacervate structure enhanced the viability of the microorganisms when exposed to a low pH environment (pH 2.0). Both encapsulated strains retained high viability in simulated gastric juice (>73%), especially in comparison with non-encapsulated (free) cells (<19%). The encapsulated lactobacilli also exhibited enhanced viability after 10–30 min of heat treatment (65oC) as well as at different NaCl concentrations (pH 4.0). Overall, the results of this study suggest that complex coacervation with WPI/GA has a potential to deliver live probiotics in low pH food systems and fermented dairy products; the complexes can dissolve at pH 7.0 (gut environment), releasing the microbial cells.

Keywords: probiotic, complex coacervation, whey, encapsulation

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3544 Universal Design for Learning: Its Impact for Enhanced Performance in General Psychology

Authors: Jose Gay D. Gallego

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This study examined the learning performance in General Psychology of 297 freshmen of the CPSU-Main through the Pre and Post Tests. The instructional intervention via Universal Design for Learning (UDL) was applied to 33% (97 out of 297) of these freshmen as the Treatment Group while the 67% (200) belonged to the Control Group for traditional instructions. Statistical inferences utilized one-way Analysis of Variance for mean differences; Pearson R Correlations for bivariate relationships, and; Factor Analysis for significant components that contributed most to the Universal Design for Learning instructions. Findings showed very high levels of students’ acquired UDL skills. Results in the pre test in General Psychology, respectively, were low and average when grouped into low and high achievers. There was no significant mean difference in the acquired nine UDL components when categorized into seven colleges to generalize that between colleges they were on the same very high levels. Significant differences were found in three test areas in General Psychology in eight colleges whose students in College of teacher education taking the lead in the learning performance. Significant differences were also traced in the post test in favor of the students in the treatment group. This proved that UDL really impacted the learning performance of the low achieving students. Significant correlations were revealed between the components of UDL and General Psychology. There were twenty four significant itemized components that contributed most to UDL instructional interventions. Implications were emphasized to maximizing the principles of UDL with the contention of thoughtful planning related to the four curricular pillars of UDL: (a) instructional goals, (b) instructional delivery methods, (c) instructional materials, and (d) student assessments.

Keywords: universal design for learning, enhanced performance, teaching innovation, technology in education, social science area

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3543 Investigating the Strategies for Managing On-plot Sanitation Systems’ Faecal Waste in Developing Regions: The Case of Ogun State, Nigeria

Authors: Olasunkanmi Olapeju

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A large chunk of global population are not yet connected to water borne faecal management systems that rely on flush mechanisms and sewers networks that are linked with a central treatment plant. Only about 10% of sub-Saharan African countries are connected to central sewage systems. In Nigeria, majority of the population do not only depend on on-plot sanitation systems, a huge chunk do not also have access to safe and improved toilets. Apart from the organizational challenges and technical capacity, the other major factors that account for why faecal waste management is yet unimproved in developing countries are faulty planning frameworks that fail to maintain balance between urbanization dynamics and infrastructures, and misconceptions about what modern sanitation is all about. In most cases, the quest to implement developmental patterns that integrate modern sewers based sanitation systems have huge financial and political costs. Faecal waste management in poor countries largely lacks the needed political attention and budgetary prioritization. Yet, the on-plot sanitation systems being mainly relied upon the need to be managed in a manner that is sustainable and healthy, pending when development would embrace a more sustainable off-site central sewage system. This study is aimed at investigating existing strategies for managing on-plot sanitation systems’ faecal waste in Ogun state, Nigeria, with the aim of recommending sustainable sanitation management systems. The study adopted the convergent parallel variant of the mixed-mode technique, which involves the adoption of both quantitative and qualitative method of data collection. Adopting a four-level multi-stage approach, which is inclusive of all political divisions in the study area, a total of 330 questionnaires were respectively administered in the study area. Moreover, the qualitative data adopted the purposive approach in scoping down to 33 key informants. SPSS software (Version 22.0) was employed for descriptively analysis. The study shows that about 52% of households adopt the non-recovery management (NRM) means of burying their latrines with sand sludge shrinkage with chemicals such as carbides. The dominance of the non-recovery management means seriously constrains the quest for faecal resource recovery. Essentially, the management techniques adopted by households depend largely on the technology of their sanitary containments, emptying means available, the ability of households to pay for the cost of emptying, and the social acceptability of the reusability of faecal waste, which determines faecal resource recoverability. The study suggests that there is a need for municipal authorities in the study area to urgently intervene in the sanitation sector and consider it a key element of the planning process. There is a need for a comprehensive plan that would ensure a seamless transition to the adoption of a modern sanitation management system.

Keywords: faecal, management, planning, waste, sanitation, sustainability

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3542 Teachers' Technological Pedagogical and Content Knowledge and Technology Integration in Teaching and Learning in a Small Island Developing State: A Concept Paper

Authors: Aminath Waseela, Vinesh Chandra, Shaun Nykvist,

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The success of technology integration initiatives hinges on the knowledge and skills of teachers to effectively integrate technology in classroom teaching. Consequently, gaining an understanding of teachers' technology knowledge and its integration can provide useful insights on strategies that can be adopted to enhance teaching and learning, especially in developing country contexts where research is scant. This paper extends existing knowledge on teachers' use of technology by developing a conceptual framework that recognises how three key types of knowledge; content, pedagogy, technology, and their integration are at the crux of teachers' technology use while at the same time is amenable to empirical studies. Although the aforementioned knowledge is important for effective use of technology that can result in enhanced student engagement, literature on how this knowledge leads to effective technology use and enhanced student engagement is limited. Thus, this theoretical paper proposes a framework to explore teachers' knowledge through the lens of the Technological Pedagogical and Content Knowledge (TPACK); the integration of technology in classroom teaching through the Substitution Augmentation Modification and Redefinition (SAMR) model and how this affects students' learning through the Bloom's Digital Taxonomy (BDT) lens. Studies using this framework could inform the design of professional development to support teachers to develop skills for effective use of available technology that can enhance student learning engagement.

Keywords: information and communication technology, ICT, in-service training, small island developing states, SIDS, student engagement, technology integration, technology professional development training, technological pedagogical and content knowledge, TPACK

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3541 Label Free Detection of Small Molecules Using Surface-Enhanced Raman Spectroscopy with Gold Nanoparticles Synthesized with Various Capping Agents

Authors: Zahra Khan

Abstract:

Surface-Enhanced Raman Spectroscopy (SERS) has received increased attention in recent years, focusing on biological and medical applications due to its great sensitivity as well as molecular specificity. In the context of biological samples, there are generally two methodologies for SERS based applications: label-free detection and the use of SERS tags. The necessity of tagging can make the process slower and limits the use for real life. Label-free detection offers the advantage that it reports direct spectroscopic evidence associated with the target molecule rather than the label. Reproducible, highly monodisperse gold nanoparticles (Au NPs) were synthesized using a relatively facile seed-mediated growth method. Different capping agents (TRIS, citrate, and CTAB) were used during synthesis, and characterization was performed. They were then mixed with different analyte solutions before drop-casting onto a glass slide prior to Raman measurements to see which NPs displayed the highest SERS activity as well as their stability. A host of different analytes were tested, both non-biomolecules and biomolecules, which were all successfully detected using this method at concentrations as low as 10-3M with salicylic acid reaching a detection limit in the nanomolar range. SERS was also performed on samples with a mixture of analytes present, whereby peaks from both target molecules were distinctly observed. This is a fast and effective rapid way of testing samples and offers potential applications in the biomedical field as a tool for diagnostic and treatment purposes.

Keywords: gold nanoparticles, label free, seed-mediated growth, SERS

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3540 Decarbonising Urban Building Heating: A Case Study on the Benefits and Challenges of Fifth-Generation District Heating Networks

Authors: Mazarine Roquet, Pierre Dewallef

Abstract:

The building sector, both residential and tertiary, accounts for a significant share of greenhouse gas emissions. In Belgium, partly due to poor insulation of the building stock, but certainly because of the massive use of fossil fuels for heating buildings, this share reaches almost 30%. To reduce carbon emissions from urban building heating, district heating networks emerge as a promising solution as they offer various assets such as improving the load factor, integrating combined heat and power systems, and enabling energy source diversification, including renewable sources and waste heat recovery. However, mainly for sake of simple operation, most existing district heating networks still operate at high or medium temperatures ranging between 120°C and 60°C (the socalled second and third-generations district heating networks). Although these district heating networks offer energy savings in comparison with individual boilers, such temperature levels generally require the use of fossil fuels (mainly natural gas) with combined heat and power. The fourth-generation district heating networks improve the transport and energy conversion efficiency by decreasing the operating temperature between 50°C and 30°C. Yet, to decarbonise the building heating one must increase the waste heat recovery and use mainly wind, solar or geothermal sources for the remaining heat supply. Fifth-generation networks operating between 35°C and 15°C offer the possibility to decrease even more the transport losses, to increase the share of waste heat recovery and to use electricity from renewable resources through the use of heat pumps to generate low temperature heat. The main objective of this contribution is to exhibit on a real-life test case the benefits of replacing an existing third-generation network by a fifth-generation one and to decarbonise the heat supply of the building stock. The second objective of the study is to highlight the difficulties resulting from the use of a fifth-generation, low-temperature, district heating network. To do so, a simulation model of the district heating network including its regulation is implemented in the modelling language Modelica. This model is applied to the test case of the heating network on the University of Liège's Sart Tilman campus, consisting of around sixty buildings. This model is validated with monitoring data and then adapted for low-temperature networks. A comparison of primary energy consumptions as well as CO2 emissions is done between the two cases to underline the benefits in term of energy independency and GHG emissions. To highlight the complexity of operating a lowtemperature network, the difficulty of adapting the mass flow rate to the heat demand is considered. This shows the difficult balance between the thermal comfort and the electrical consumption of the circulation pumps. Several control strategies are considered and compared to the global energy savings. The developed model can be used to assess the potential for energy and CO2 emissions savings retrofitting an existing network or when designing a new one.

Keywords: building simulation, fifth-generation district heating network, low-temperature district heating network, urban building heating

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3539 Reconstruction Post-mastectomy: A Literature Review on Its Indications and Techniques

Authors: Layaly Ayoub, Mariana Ribeiro

Abstract:

Introduction: Breast cancer is currently considered the leading cause of cancer-related deaths among women in Brazil. Mastectomy, essential in this treatment, often necessitates subsequent breast reconstruction to restore physical appearance and aid in the emotional and psychological recovery of patients. The choice between immediate or delayed reconstruction is influenced by factors such as the type and stage of cancer, as well as the patient's overall health. The decision between autologous breast reconstruction or implant-based reconstruction requires a detailed analysis of individual conditions and needs. Objectives: This study analyzes the techniques and indications used in post-mastectomy breast reconstruction. Methodology: Literature review conducted in the PubMed and SciELO databases, focusing on articles that met the inclusion and exclusion criteria and descriptors. Results: After mastectomy, breast reconstruction is commonly performed. It is necessary to determine the type of technique to be used in each case depending on the specific characteristics of each patient. The tissue expander technique is indicated for patients with sufficient skin and tissue post-mastectomy, who do not require additional radiotherapy, and who opt for a less complex surgery with a shorter recovery time. This procedure promotes the gradual expansion of soft tissues where the definitive implant will be placed. Both temporary and permanent expanders offer flexibility, allowing for adjustment in the expander size until the desired volume is reached, enabling the skin and tissues to adapt to the breast implant area. Conversely, autologous reconstruction is indicated for patients who will undergo radiotherapy, have insufficient tissue, and prefer a more natural solution. This technique uses the transverse rectus abdominis muscle (TRAM) flap, the latissimus dorsi muscle flap, the gluteal flap, and local muscle flaps to shape a new breast, potentially combined with a breast implant. Conclusion: In this context, it is essential to conduct a thorough evaluation regarding the technique to be applied, as both have their benefits and challenges.

Keywords: indications, post-mastectomy, breast reconstruction, techniques

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3538 Bacterial Causes of Cerebral Abscess and Impact on Long Term Patient Outcomes

Authors: Umar Rehman, Holly Roy, K. T. Tsang, D. S. Jeyaretna, W Singleton, B. Fisher, P. A. Glew, J. Greig, Peter C. Whitfield

Abstract:

Introduction: A brain abscess is a life-threatening condition, carrying significant mortality. It requires rapid identification and treatment. Management involves a combination of antibiotics and surgery. The aim of the current study was to identify common bacteria responsible for cerebral abscesses as well as the long term functional and neurological outcomes of patients following treatment in a retrospective series at a single UK neurosurgical centre. Methodology: We analysed patients that had received a diagnosis of 'cerebral abscess' or 'subdural empyema' between June 2002 and June 2018. This was done in the form of a retrospective review. The search resulted in a total of 180 patients; with 37 patients being excluded (spinal abscess, below 18 or non-abscess related admissions). Data were collected from medical case notes including information about demographics, comorbidities, immunosuppression, presentation, size/location of lesions, pathogens, treatment, and outcomes. Results: In total, we analysed 143 patients between the ages of 18-90. Focal neurological deficit and headaches were seen in 84% and 68% of patients respectively. 108 positive brain cultures were seen; with the largest proportion, 59.2% being gram-positive cocci, with strep intermedius being the most common pathogen identified in 13.9% of patients. Of the patients with positive blood cultures (n=11), 72.7% showed the same organism both in the blood and on the brain cultures. Long term outcomes (n=72) revealed that 48% of patients seizure-free without requiring anti-epileptics, 51.3% of patients had full recovery of their neurological symptoms. There was a mortality rate of 13.9% in the series. Conclusion: In conclusion, the largest bacterial cause of abscess within our population was due to gram-positive cocci. The majority of the patient demonstrated full neurological recovery with close to half of patients not requiring anti-epileptics following discharge.

Keywords: bacteria, cerebral abscess, long term outcome, neurological deficit

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3537 Improving Fault Tolerance and Load Balancing in Heterogeneous Grid Computing Using Fractal Transform

Authors: Saad M. Darwish, Adel A. El-Zoghabi, Moustafa F. Ashry

Abstract:

The popularity of the Internet and the availability of powerful computers and high-speed networks as low-cost commodity components are changing the way we use computers today. These technical opportunities have led to the possibility of using geographically distributed and multi-owner resources to solve large-scale problems in science, engineering, and commerce. Recent research on these topics has led to the emergence of a new paradigm known as Grid computing. To achieve the promising potentials of tremendous distributed resources, effective and efficient load balancing algorithms are fundamentally important. Unfortunately, load balancing algorithms in traditional parallel and distributed systems, which usually run on homogeneous and dedicated resources, cannot work well in the new circumstances. In this paper, the concept of a fast fractal transform in heterogeneous grid computing based on R-tree and the domain-range entropy is proposed to improve fault tolerance and load balancing algorithm by improve connectivity, communication delay, network bandwidth, resource availability, and resource unpredictability. A novel two-dimension figure of merit is suggested to describe the network effects on load balance and fault tolerance estimation. Fault tolerance is enhanced by adaptively decrease replication time and message cost while load balance is enhanced by adaptively decrease mean job response time. Experimental results show that the proposed method yields superior performance over other methods.

Keywords: Grid computing, load balancing, fault tolerance, R-tree, heterogeneous systems

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3536 Emergency Surgery in the Elderly, What Particularities

Authors: Mekroud Amel

Abstract:

Introduction The rate of use by the elderly of emergency departments, operating rooms and intensive care units has increased worldwide. Emergency surgery is a context where evaluation is often insufficient, with incomplete information gathering. The aim of this work is to shed light on the frequent use of emergency surgeries by the elderly and their characteristics, as well as on the lack of geriatric assessment scores in the emergency room. Material : Prospective, observational and descriptive, monocentric study. Patients aged 65 and over, admitted for emergency surgery in the operating room, were counted. Emergency operating room including visceral surgery, urology, traumatology and neurosurgery. Parameters studied: Patient characteristics, degree of autonomy, type of surgical pathology, operative management times, preoperative evaluation, postoperative outcome Results : 192 patients were identified over 12 months, from 09.01.2017 to 08.31.2018 Age from 65 to 101 years, 79.81 years +/- 8.38. With predominance of the age group between [65-75 years] 41.1% Female predominance, Sexratio = 0.81 Elderly subjects with total motor autonomy are in the majority at 57.8% Subjects without pathological ATCD represent 12.5% of cases Those who are on only one type of medication or without any treatment are at 36.9% Discussion : The emergency operative care of the elderly patient for a surgical or traumatological pathology is characterized by many specificities linked first to the emergency context, where the evaluation is often insufficient, besides the fact that the elderly patient has particularities requiring reception in centers with experience in the care of this category of patient, or, failing that, a center which uses the minimum of geriatric evaluation scores which are simplified for the emergency departments. In our hospital, we have not yet made this evaluation routine in the emergency room and this delay in the introduction of these scores can be directly attributed to the covid 19 pandemic. Besides the standard preoperative assessment, only 43.2% of patients were assessed in the preoperative period by an anesthesiologist. Traumatological emergencies come first 68.2% followed by visceral emergencies 19.2% (including proctological, urological emergencies), neurosurgical emergencies 7.8% and finally peripheral emergency surgery all acts combined 4.7%. Hospital stay at 9.6 +/- 16.8 days, average operability time of 4.5 +/- 3 days. Death rate at 7.29% Conclusion This work has demonstrated the major impact of emergency surgery, which remains curable for the most part, on the elderly patient despite total motor and cognitive autonomy preoperatively. The improvement of the preoperative evaluation, the reduction of the operating time and enhanced recovery after surgery, with personalized protocols, are the only guarantee for the resumption of preoperative autonomy in these patients.

Keywords: emergency surgery, elderly patients, preoperative geriatric scores, curable emergency surgical pathologies

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3535 Cytotoxic and Biocompatible Evaluation of Silica Coated Silver Nanoparticle Against Nih-3t3 Cells

Authors: Chen-En Lin, Lih-Rou Rau, Jiunn-Woei Liaw, Shiao-Wen Tsai

Abstract:

The unique optical properties of plasmon resonance metallic particles have attracted considerable applications in the fields of physics, chemistry and biology. Metal-Enhanced Fluorescence (MEF) effect is one of the useful applications. MEF effect stated that fluorescence intensity can be quenched or be enhanced depending on the distance between fluorophores and the metal nanoparticles. Silver nanoparticles have used widely in antibacterial studies. However, the major limitation for silver nanoparticles (AgNPs) in biomedical application is well-known cytotoxicity on cells. There were numerous literatures have been devoted to overcome the disadvantage. The aim of the study is to evaluate the cytotoxicity and biocompatibility of silica coated AgNPs against NIH-3T3 cells. The results were shown that NIH-3T3 cells started to detach, shrink, become rounded and finally be irregular in shape after 24 h of exposure at 10 µg/ml AgNPs. Besides, compared with untreated cells, the cell viability significantly decreased to 60% and 40% which were exposed to 10 µg/ml and 20 µg/ml AgNPs respectively. The result was consistent with previously reported findings that AgNPs induced cytotoxicity was concentration dependent. However, the morphology and cell viability of cells appeared similar to the control group when exposed to 20 µg/ml of silica coated AgNPs. We further utilized the dark-field hyperspectral imaging system to analysis the optical properties of the intracellular nanoparticles. The image displayed that the red shift of the surface plasmonic resonances band of the enclosed AgNPs further confirms the agglomerate of the AgNPs rather than their distribution in cytoplasm. In conclusion, the study demonstrated the silica coated of AgNPs showed well biocompatibility and significant lower cytotoxicity compared with bare AgNPs.

Keywords: silver nanoparticles, silica, cell viability, morphology

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3534 Architecture - Performance Relationship in GPU Computing - Composite Process Flow Modeling and Simulations

Authors: Ram Mohan, Richard Haney, Ajit Kelkar

Abstract:

Current developments in computing have shown the advantage of using one or more Graphic Processing Units (GPU) to boost the performance of many computationally intensive applications but there are still limits to these GPU-enhanced systems. The major factors that contribute to the limitations of GPU(s) for High Performance Computing (HPC) can be categorized as hardware and software oriented in nature. Understanding how these factors affect performance is essential to develop efficient and robust applications codes that employ one or more GPU devices as powerful co-processors for HPC computational modeling. This research and technical presentation will focus on the analysis and understanding of the intrinsic interrelationship of both hardware and software categories on computational performance for single and multiple GPU-enhanced systems using a computationally intensive application that is representative of a large portion of challenges confronting modern HPC. The representative application uses unstructured finite element computations for transient composite resin infusion process flow modeling as the computational core, characteristics and results of which reflect many other HPC applications via the sparse matrix system used for the solution of linear system of equations. This work describes these various software and hardware factors and how they interact to affect performance of computationally intensive applications enabling more efficient development and porting of High Performance Computing applications that includes current, legacy, and future large scale computational modeling applications in various engineering and scientific disciplines.

Keywords: graphical processing unit, software development and engineering, performance analysis, system architecture and software performance

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3533 Effects of Tramadol Administration on the Ovary of Adult Rats and the Possible Recovery after Tramadol Withdrawal: A Light and Electron Microscopic Study

Authors: Heba Kamal Mohamed

Abstract:

Introduction: Tramadol is a weak -opioid receptor agonist with an analgesic effect because of the inhibition of uptake of norepinephrine and serotonin. Nowadays, tramadol hydrochloride is frequently used as a pain reliever. Tramadol is recommended for the management of acute and chronic pain of moderate to severe intensity associated with a variety of diseases or problems, including osteoarthritis, diabetic neuropathy, neuropathic pain, and even perioperative pain in human patients. In obstetrics and gynecology, tramadol is used extensively to treat postoperative pain. Aim of the study: This study was undertaken to investigate the histological (light and electron microscopic) and immunohistochemical effects of long term tramadol treatment on the ovary of adult rats and the possible recovery after tramadol withdrawal. Design: Experimental study. Materials and methods: Thirty adult female albino rats were used in this study. They were classified into three main groups (10 rats each). Group I served as the control group. Group II, rats were subcutaneously injected with tramadol 40 mg/kg three times per week for 8 weeks. Group III, rats were subcutaneously injected with tramadol 40 mg/kg three times per week for 8 weeks then were kept for another 8 weeks without treatment for recovery. At the end of the experiment rats were sacrificed and bilateral oophorectomy was carried out; the ovaries were processed for histological study (light and electron microscopic) and immunohistochemical reaction for caspase-3 (apoptotic protein). Results: Examination of the ovary of tramadol-treated rats (group II) revealed many atretic ovarian follicles, some follicles showed detachment of the oocyte from surrounding granulosa cells and others showed loss of the oocyte. Many follicles revealed degenerated vacuolated oocytes and vacuolated theca folliculi cells. Granulosa cells appeared shrunken, disrupted and loosely attached with vacuolated cytoplasm and pyknotic nuclei. Some follicles showed separation of granulosa cells from the theca folliculi layer. The ultrastructural study revealed the presence of granulosa cells with electron dense indented nuclei, damaged mitochondria and granular vacuolated cytoplasm. Other cells showed accumulation of large amount of lipid droplets in their cytoplasm. Some follicles revealed rarifaction of the cytoplasm of oocytes and absent zona pellucida. Moreover, apoptotic changes were detected by immunohistochemical staining in the form of increased staining intensity to caspase-3 (apoptotic protein). With Masson's Trichrome stain, there was an increased collagen fibre deposition in the ovarian cortical stroma. The wall of blood vessels appeared thickened. In the withdrawal group (group III), there was a little improvement in the histological and immunohistochemical changes. Conclusion: Tramadol had serious deleterious effects on ovarian structure. Thus, it should be used with caution, especially when a long term treatment is indicated. Withdrawal of tramadol led to a little improvement in the structural impairment of the ovary.

Keywords: tramadol, ovary, withdrawal, rats

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3532 Intensity-Enhanced Super-Resolution Amplitude Apodization Effect on the Non-Spherical Near-Field Particle-Lenses

Authors: Liyang Yue, Bing Yan, James N. Monks, Rakesh Dhama, Zengbo Wang, Oleg V. Minin, Igor V. Minin

Abstract:

A particle can function as a refractive lens to focus a plane wave, generating a narrow, high intensive, weak-diverging beam within a sub-wavelength volume, known as the ‘photonic jet’. Refractive index contrast (particle to background media) and scaling effect of the dielectric particle (relative-to-wavelength size) play key roles in photonic jet formation, rather than the shape of particle-lens. Waist (full width of half maximum, FWHM) of a photonic jet could be beyond the diffraction limit and smaller than the Airy disk, which defines the minimum distance between two objects to be imaged as two instead of one. Many important applications for imaging and sensing have been afforded based upon the super-resolution characteristic of the photonic jet. It is known that apodization method, in the form of an amplitude pupil-mask centrally situated on a particle-lens, can further reduce the waist of a photonic nanojet, however, usually lower its intensity at the focus due to blocking of the incident light. In this paper, the anomalously intensity-enhanced apodization effect was discovered in the near-field via numerical simulation. It was also experimentally verified by a scale model using a copper-masked Teflon cuboid solid immersion lens (SIL) with 22 mm side length under radiation of a plane wave with 8 mm wavelength. Peak intensity enhancement and the lateral resolution of the produced photonic jet increased by about 36.0 % and 36.4 % in this approach, respectively. This phenomenon may possess the scale effect and would be valid in multiple frequency bands.

Keywords: apodization, particle-lens, scattering, near-field optics

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3531 Modified Norhaya Upper Limp Elevation Sling-Quick Approach Ensuring Timely Limb Elevation

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

Abstract:

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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3530 A Strategy to Oil Production Placement Zones Based on Maximum Closeness

Authors: Waldir Roque, Gustavo Oliveira, Moises Santos, Tatiana Simoes

Abstract:

Increasing the oil recovery factor of an oil reservoir has been a concern of the oil industry. Usually, the production placement zones are defined after some analysis of geological and petrophysical parameters, being the rock porosity, permeability and oil saturation of fundamental importance. In this context, the determination of hydraulic flow units (HFUs) renders an important step in the process of reservoir characterization since it may provide specific regions in the reservoir with similar petrophysical and fluid flow properties and, in particular, techniques supporting the placement of production zones that favour the tracing of directional wells. A HFU is defined as a representative volume of a total reservoir rock in which petrophysical and fluid flow properties are internally consistent and predictably distinct of other reservoir rocks. Technically, a HFU is characterized as a rock region that exhibit flow zone indicator (FZI) points lying on a straight line of the unit slope. The goal of this paper is to provide a trustful indication for oil production placement zones for the best-fit HFUs. The FZI cloud of points can be obtained from the reservoir quality index (RQI), a function of effective porosity and permeability. Considering log and core data the HFUs are identified and using the discrete rock type (DRT) classification, a set of connected cell clusters can be found and by means a graph centrality metric, the maximum closeness (MaxC) cell is obtained for each cluster. Considering the MaxC cells as production zones, an extensive analysis, based on several oil recovery factor and oil cumulative production simulations were done for the SPE Model 2 and the UNISIM-I-D synthetic fields, where the later was build up from public data available from the actual Namorado Field, Campos Basin, in Brazil. The results have shown that the MaxC is actually technically feasible and very reliable as high performance production placement zones.

Keywords: hydraulic flow unit, maximum closeness centrality, oil production simulation, production placement zone

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