Search results for: Sandra Thompson
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 231

Search results for: Sandra Thompson

111 The Impact of Virtual Learning Strategy on Youth Learning Motivation in Malaysian Higher Learning Instituitions

Authors: Hafizah Harun, Habibah Harun, Azlina Kamaruddin

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Virtual reality has become a powerful and promising tool in education because of their unique technological characteristics that differentiate them from the other ICT applications. Despite the numerous interpretations of its definition, virtual reality can be concisely and precisely described as the integration of computer graphics and various input and display technologies to create the illusion of immersion in a computer generated reality. Generally, there are two major types based on the level of interaction and immersive environment that are immersive and non-immersive virtual reality. In the study of the role of virtual reality in built environment education, Horne and Thompson were reported as saying that the benefits of using visualization technologies were seen as having the potential to improve and extend the learning process, increase student motivation and awareness, and add to the diversity of teaching methods. Youngblut reported that students enjoy working with virtual worlds and this experience can be highly motivating. The impact of virtual reality on youth learning in Malaysia is currently not well explored because the technology is still not widely used here. Only a handful of the universities, such as University Malaya, MMU, and Unimas are applying virtual reality strategy in some of their undergraduate programs. From the literature, it has been identified that there are several virtual reality learning strategies currently available. Therefore, this study aims to investigate the impact of Virtual Reality strategy on Youth Learning Motivation in Malaysian higher learning institutions. We will explore the relationship between virtual reality (gaming, laboratory, simulation) and youth leaning motivation. Another aspect that we will explore is the framework for virtual reality implementation at higher learning institution in Malaysia. This study will be carried out quantitatively by distributing questionnaires to respondents from sample universities. Data analysis are descriptive and multiple regression. Researcher will carry out a pilot test prior to distributing the questionnaires to 300 undergraduate students who are undergoing their courses in virtual reality environment. The respondents come from two universities, MMU CyberJaya and University Malaya. The expected outcomes from this study are the identification of which virtual reality strategy has most impact on students’ motivation in learning and a proposed framework of virtual reality implementation at higher learning.

Keywords: virtual reality, learning strategy, youth learning, motivation

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110 Identification of New Familial Breast Cancer Susceptibility Genes: Are We There Yet?

Authors: Ian Campbell, Gillian Mitchell, Paul James, Na Li, Ella Thompson

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The genetic cause of the majority of multiple-case breast cancer families remains unresolved. Next generation sequencing has emerged as an efficient strategy for identifying predisposing mutations in individuals with inherited cancer. We are conducting whole exome sequence analysis of germ line DNA from multiple affected relatives from breast cancer families, with the aim of identifying rare protein truncating and non-synonymous variants that are likely to include novel cancer predisposing mutations. Data from more than 200 exomes show that on average each individual carries 30-50 protein truncating mutations and 300-400 rare non-synonymous variants. Heterogeneity among our exome data strongly suggest that numerous moderate penetrance genes remain to be discovered, with each gene individually accounting for only a small fraction of families (~0.5%). This scenario marks validation of candidate breast cancer predisposing genes in large case-control studies as the rate-limiting step in resolving the missing heritability of breast cancer. The aim of this study is to screen genes that are recurrently mutated among our exome data in a larger cohort of cases and controls to assess the prevalence of inactivating mutations that may be associated with breast cancer risk. We are using the Agilent HaloPlex Target Enrichment System to screen the coding regions of 168 genes in 1,000 BRCA1/2 mutation-negative familial breast cancer cases and 1,000 cancer-naive controls. To date, our interim analysis has identified 21 genes which carry an excess of truncating mutations in multiple breast cancer families versus controls. Established breast cancer susceptibility gene PALB2 is the most frequently mutated gene (13/998 cases versus 0/1009 controls), but other interesting candidates include NPSR1, GSN, POLD2, and TOX3. These and other genes are being validated in a second cohort of 1,000 cases and controls. Our experience demonstrates that beyond PALB2, the prevalence of mutations in the remaining breast cancer predisposition genes is likely to be very low making definitive validation exceptionally challenging.

Keywords: predisposition, familial, exome sequencing, breast cancer

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109 Energy Efficient Retrofitting and Optimization of Dual Mixed Refrigerant Natural Gas Liquefaction Process

Authors: Muhammad Abdul Qyyum, Kinza Qadeer, Moonyong Lee

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Globally, liquefied natural gas (LNG) has drawn interest as a green energy source in comparison with other fossil fuels, mainly because of its ease of transport and low carbon dioxide emissions. It is expected that demand for LNG will grow steadily over the next few decades. In addition, because the demand for clean energy is increasing, LNG production facilities are expanding into new natural gas reserves across the globe. However, LNG production is an energy and cost intensive process because of the huge power requirements for compression and refrigeration. Therefore, one of the major challenges in the LNG industry is to improve the energy efficiency of existing LNG processes through economic and ecological strategies. The advancement in expansion devices such as two-phase cryogenic expander (TPE) and cryogenic hydraulic turbine (HT) were exploited for energy and cost benefits in natural gas liquefaction. Retrofitting the conventional Joule–Thompson (JT) valve with TPE and HT have the potential to improve the energy efficiency of LNG processes. This research investigated the potential feasibility of the retrofitting of a dual mixed refrigerant (DMR) process by replacing the isenthalpic expansion with isentropic expansion corresponding to energy efficient LNG production. To fully take the potential benefit of the proposed process retrofitting, the proposed DMR schemes were optimized by using a Coggins optimization approach, which was implemented in Microsoft Visual Studio (MVS) environment and linked to the rigorous HYSYS® model. The results showed that the required energy of the proposed isentropic expansion based DMR process could be saved up to 26.5% in comparison with the conventional isenthalpic based DMR process using the JT valves. Utilization of the recovered energy into boosting the natural gas feed pressure could further improve the energy efficiency of the LNG process up to 34% as compared to the base case. This work will help the process engineers to overcome the challenges relating to energy efficiency and safety concerns of LNG processes. Furthermore, the proposed retrofitting scheme can also be implemented to improve the energy efficiency of other isenthalpic expansion based energy intensive cryogenic processes.

Keywords: cryogenic liquid turbine, Coggins optimization, dual mixed refrigerant, energy efficient LNG process, two-phase expander

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108 Exploring SL Writing and SL Sensitivity during Writing Tasks: Poor and Advanced Writing in a Context of Second Language other than English

Authors: Sandra Figueiredo, Margarida Alves Martins, Carlos Silva, Cristina Simões

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This study integrates a larger research empirical project that examines second language (SL) learners’ profiles and valid procedures to perform complete and diagnostic assessment in schools. 102 learners of Portuguese as a SL aged 7 and 17 years speakers of distinct home languages were assessed in several linguistic tasks. In this article, we focused on writing performance in the specific task of narrative essay composition. The written outputs were measured using the score in six components adapted from an English SL assessment context (Alberta Education): linguistic vocabulary, grammar, syntax, strategy, socio-linguistic, and discourse. The writing processes and strategies in Portuguese language used by different immigrant students were analysed to determine features and diversity of deficits on authentic texts performed by SL writers. Differentiated performance was based on the diversity of the following variables: grades, previous schooling, home language, instruction in first language, and exposure to Portuguese as Second Language. Indo-Aryan languages speakers showed low writing scores compared to their peers and the type of language and respective cognitive mapping (such as Mandarin and Arabic) was the predictor, not linguistic distance. Home language instruction should also be prominently considered in further research to understand specificities of cognitive academic profile in a Romance languages learning context. Additionally, this study also examined the teachers representations that will be here addressed to understand educational implications of second language teaching in psychological distress of different minorities in schools of specific host countries.

Keywords: home language, immigrant students, Portuguese language, second language, writing assessment

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107 Life Cycle Assessment of Rare Earth Metals Production: Hotspot Analysis of Didymium Electrolysis Process

Authors: Sandra H. Fukurozaki, Andre L. N. Silva, Joao B. F. Neto, Fernando J. G. Landgraf

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Nowadays, the rare earth (RE) metals play an important role in emerging technologies that are crucial for the decarbonisation of the energy sector. Their unique properties have led to increasing clean energy applications, such as wind turbine generators, and hybrid and electric vehicles. Despite the substantial media coverage that has recently surrounded the mining and processing of rare earth metals, very little quantitative information is available concerning their subsequent life stages, especially related to the metallic production of didymium (Nd-Pr) in fluoride molten salt system. Here we investigate a gate to gate scale life cycle assessment (LCA) of the didymium electrolysis based on three different scenarios of operational conditions. The product system is modeled with SimaPro Analyst 8.0.2 software, and IMPACT 2002+ was applied as an impact assessment tool. In order to develop a life cycle inventories built in software databases, patents, and other published sources together with energy/mass balance were utilized. Analysis indicates that from the 14 midpoint impact categories evaluated, the global warming potential (GWP) is the main contributors to the total environmental burden, ranging from 2.7E2 to 3.2E2 kg CO2eq/kg Nd-Pr. At the damage step assessment, the results suggest that slight changes in materials flows associated with enhancement of current efficiency (between 2.5% and 5%), could lead a reduction up to 12% and 15% of human health and climate change damage, respectively. Additionally, this paper highlights the knowledge gaps and future research efforts needing to understand the environmental impacts of Nd-Pr electrolysis process from the life cycle perspective.

Keywords: didymium electrolysis, environmental impacts, life cycle assessment, rare earth metals

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106 Physicochemical Stability of Pulse Spreads during Storage after Sous Vide Treatment and High Pressure Processing

Authors: Asnate Kirse, Daina Karklina, Sandra Muizniece-Brasava, Ruta Galoburda

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Pulses are high in plant protein and dietary fiber, and contain slowly digestible starches. Innovative products from pulses could increase their consumption and benefit consumer health. This study was conducted to evaluate physicochemical stability of processed cowpea (Vigna unguiculata (L.) Walp. cv. Fradel) and maple pea (Pisum sativum var. arvense L. cv. Bruno) spreads at 5 °C temperature during 62-day storage. Physicochemical stability of pulse spreads was compared after sous vide treatment (80 °C/15 min) and high pressure processing (700 MPa/10 min/20 °C). Pulse spreads were made by homogenizing cooked pulses in a food processor together with salt, citric acid, oil, and bruschetta seasoning. A total of four different pulse spreads were studied: Cowpea spread without and with seasoning, maple pea spread without and with seasoning. Transparent PA/PE and light proof PET/ALU/PA/PP film pouches were used for packaging of pulse spreads under vacuum. The parameters investigated were pH, water activity and mass losses. Pulse spreads were tested on days 0, 15, 29, 42, 50, 57 and 62. The results showed that sous-vide treatment and high pressure processing had an insignificant influence on pH, water activity and mass losses after processing, irrespective of packaging material did not change (p>0.1). pH and water activity of sous-vide treated and high pressure processed pulse spreads in different packaging materials proved to be stable throughout the storage. Mass losses during storage accounted to 0.1% losses. Chosen sous-vide treatment and high pressure processing regimes and packaging materials are suitable to maintain consistent physicochemical quality of the new products during 62-day storage.

Keywords: cowpea, flexible packaging, maple pea, water activity

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105 Use of Metallic and Bimetallic Nanostructures as Constituents of Active Bio-Based Films

Authors: Lina F. Ballesteros, Hafsae Lamsaf, Miguel A. Cerqueira, Lorenzo M. Pastrana, Sandra Carvalho, Jose A. Teixeira, S. Calderon V.

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The use of bio-based packaging materials containing metallic and bimetallic nanostructures is relatively modern technology. In this sense, the food packaging industry has been investigating biological and renewable resources that can replace petroleum-based materials to reduce the environmental impact and, at the same time, including new functionalities using nanotechnology. Therefore, the main objective of the present work consisted of developing bio-based poly-lactic acid (PLA) films with Zinc (Zn) and Zinc-Iron (Zn-Fe) nanostructures deposited by magnetron sputtering. The structural, antimicrobial, and optical properties of the films were evaluated when exposed at 60% and 96% relative humidity (RH). The morphology and elemental analysis of the samples were determined by scanning (transmission) electron microscopy (SEM and STEM), and inductively coupled plasma optical emission spectroscopy (ICP-OES). The structure of the PLA was monitored before and after deposition by Fourier transform infrared spectroscopy (FTIR) analysis, and the antimicrobial and color assays were performed by using the zone of inhibition (ZOI) test and a Minolta colorimeter, respectively. Finally, the films were correlated in terms of the deposit conditions, Zn or Zn-Fe concentrations, and thickness. The results revealed PLA films with different morphologies, compositions, and thicknesses of Zn or Zn-Fe nanostructures. The samples showed a significant antibacterial and antifungal activity against E. coli, P. aeruginosa, P. fluorescens, S. aureus, and A. niger, and considerable changes of color and opacity at 96% RH, especially for the thinner nanostructures (150-250 nm). On the other hand, when the Fe fraction was increased, the lightness of samples increased, as well as their antimicrobial activity when compared to the films with pure Zn. Hence, these findings are relevant to the food packaging field since intelligent and active films with multiple properties can be developed.

Keywords: biopolymers, functional properties, magnetron sputtering, Zn and Zn-Fe nanostructures

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104 Predicting Mass-School-Shootings: Relevance of the FBI’s ‘Threat Assessment Perspective’ Two Decades Later

Authors: Frazer G. Thompson

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The 1990s in America ended with a mass-school-shooting (at least four killed by gunfire excluding the perpetrator(s)) at Columbine High School in Littleton, Colorado. Post-event, many demanded that government and civilian experts develop a ‘profile’ of the potential school shooter in order to identify and preempt likely future acts of violence. This grounded theory research study seeks to explore the validity of the original hypotheses proposed by the Federal Bureau of Investigation (FBI) in 2000, as it relates to the commonality of disclosure by perpetrators of mass-school-shootings, by evaluating fourteen mass-school-shooting events between 2000 and 2019 at locations around the United States. Methods: The strategy of inquiry seeks to investigate case files, public records, witness accounts, and available psychological profiles of the shooter. The research methodology is inclusive of one-on-one interviews with members of the FBI’s Critical Incident Response Group seeking perspective on commonalities between individuals; specifically, disclosure of intent pre-event. Results: The research determined that school shooters do not ‘unfailingly’ notify others of their plans. However, in nine of the fourteen mass-school-shooting events analyzed, the perpetrator did inform the third party of their intent pre-event in some form of written, oral, or electronic communication. In the remaining five instances, the so-called ‘red-flag’ indicators of the potential for an event to occur were profound, and unto themselves, might be interpreted as notification to others of an imminent deadly threat. Conclusion: Data indicates that conclusions drawn in the FBI’s threat assessment perspective published in 2000 are relevant and current. There is evidence that despite potential ‘red-flag’ indicators which may or may not include a variety of other characteristics, perpetrators of mass-school-shooting events are likely to share their intentions with others through some form of direct or indirect communication. More significantly, implications of this research might suggest that society is often informed of potential danger pre-event but lacks any equitable means by which to disseminate, prevent, intervene, or otherwise act in a meaningful way considering said revelation.

Keywords: columbine, FBI profiling, guns, mass shooting, mental health, school violence

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103 Between the Pen and the Dish Towel: Paradox of Globalization

Authors: Sandra Maria Cerqueira Da Silva

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In Brazil, women are the majority of the country's population. They have advanced in terms of years of education and professional training. However, this has not prevented the differences in the labor market from being sustained, particularly the wage gap and inequalities concerning the access to command positions and promotions, i.e., in the gender relations and treatment. One of the conditions which constitute a barrier to career advancement is the necessary support chain to support women when they are in the labor market. Therefore, the purpose of this research is to demonstrate, describe, and criticize some of the current conformations of support chains and how these compete to promote the phenomenon known as glass ceiling in the country. However, this support may come even from inside a woman's own home, with a fairer division of household activities between men and women. Such behavior can free an entire network of women within the same family. In addition, it can serve as pressure to structure better conditions for women as a whole, improving the living conditions of the poor population. This can occur through programs and projects for qualification and retraining of adult women. In answer to the question that guides this study, it is concluded that a family support system is critical to the success of women in management positions. To meet this demand, one of the ways could be the development of specific gender policies by the public authorities, in accordance with the emerging global economic policies, in order to provide and structure the necessary support. This would respond to feminist manifestations - which should go on pointing needs – although the legislative assembly should also propose ideas to change this picture. This is a qualitative research, with a poststructuralist approach, featuring a cutout corpus of three interviews carried out with women holding leadership positions in the academia. Questions related to this very discussion are many. New studies could address points as the promotion of qualification and expansion of skills of women in subaltern condition. There is also need to investigate possible support systems, considering the inequalities and local economic conditions.

Keywords: gender and labor market, glass ceiling, post-structuralism, support chain

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102 Clove Oil Incorporated Biodegradable Film for Active Food Packaging

Authors: Shubham Sharma, Sandra Barkauskaite, Brendan Duffy, Swarna Jaiswal, Amit K. Jaiswal

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Food packaging protects food from temperature, light, and humidity; preserves food and guarantees the safety and the integrity of the food. Advancement in packaging research leads to development of active packaging system with numerous properties such as oxygen scavengers, carbon-dioxide generating systems, antimicrobial active packaging, moisture control packaging, ethylene scavengers etc. In the active packaging, several additives such as essential oils, polyphenols etc. are incorporated into packaging film or within the packaging material to achieve the desired properties. This study investigates the effect on the structural, thermal and functional properties of different poly(lactide) – poly (butylene adipate-co-terephthalate) (PLA-PBAT) blend films incorporated with clove essential oil. The PLA-PBAT films were prepared by a solution casting method and then characterized based on their optical, mechanical properties, surface hydrophobicity, chemical composition, antimicrobial activity against S. aureus and E. coli, and inhibition of biofilm formation of E. coli. Results showed that, the developed packaging film containing clove oil has significant UV-blocking property (80%). However, incorporation of clove oil resulted in reduced transparency and tensile strength of the film as the concentration of clove oil increased. The surface hydrophobicity of packaging film was improved with the increasing concentration of essential oil. Similarly, thickness of the clove oil containing films increased from 36.71 µm to 106.67 µm as the concentration increases. The antimicrobial activity and biofilm inhibition study showed that the clove-incorporated PLA-PBAT composite film was effective against tested bacteria E. coli and S. aureus. This study showed that the PLA-PBAT – Clove oil composite film has significant antimicrobial and UV-blocking properties and can be used as an active food packaging film.

Keywords: active packaging, clove oil, poly(butylene adipate-co-terephthalate), poly(lactide)

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101 Economic Analysis of Rainwater Harvesting Systems for Dairy Cattle

Authors: Sandra Cecilia Muhirirwe, Bart Van Der Bruggen, Violet Kisakye

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Economic analysis of Rainwater harvesting (RWH) systems is vital in search of a cost-effective solution to water unreliability, especially in low-income countries. There is little literature focusing on the financial aspects of RWH for dairy farmers. The main purpose was to assess the economic viability of rainwater harvesting for diary framers in the Rwenzori region. The study focused on the use of rainwater harvesting systems from the rooftop and collection in above surface tanks. Daily rainfall time series for 12 years was obtained across nine gauging stations. The daily water balance equation was used for optimal sizing of the tank. Economic analysis of the investment was carried out based on the life cycle costs and the accruing benefits for the period of 15 years. Roof areas were varied from 75m2 as the minimum required area to 500m2 while maintaining the same number of cattle and keeping the daily water demand constant. The results show that the required rainwater tank sizes are very large and may be impractical to install due to the strongly varying terrain and the initial cost of investment. In all districts, there is a significant reduction of the volume of the required tank with an increasing collection area. The results further show that increasing the collection area has a minor effect on reducing the required tank size. Generally, for all rainfall areas, the reliability increases with an increase in the roof area. The results indicate that 100% reliability can only be realized with very large collection areas that are impractical to install. The estimated benefits outweigh the cost of investment. The Present Net Value shows that the investment is economically viable and investment with a short payback of a maximum of 3 years for all the time series in the study area.

Keywords: dairy cattle, optimisation, rainwater harvesting, economic analysis

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100 Students' Performance, Perception and Attitude towards Interactive Online Modules to Improve Undergraduate Quantitative Skills in Biological Science

Authors: C. Suphioglu , V. Simbag, J. Markham, C. Coady, S. Belward, G. Di Trapani, P. Chunduri, J. Chuck, Y. Hodgson, L. Lluka, L. Poladian, D. Watters

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Advances in science have made quantitative skills (QS) an essential graduate outcome for undergraduate science programs in Australia and other parts of the world. However, many students entering into degrees in Australian universities either lack these skills or have little confidence in their ability to apply them in their biological science units. It has been previously reported that integration of quantitative skills into life science programs appears to have a positive effect on student attitudes towards the importance of mathematics and statistics in biological sciences. It has also been noted that there is deficiency in QS resources available and applicable to undergraduate science students in Australia. MathBench (http://mathbench.umd.edu) is a series of online modules involving quantitative biology scenarios developed by the University of Maryland. Through collaboration with Australian universities, a project was funded by the Australian government through its Office for Learning and Teaching (OLT) to develop customized MathBench biology modules to promote the quantitative skills of undergraduate biology students in Australia. This presentation will focus on the assessment of changes in performance, perception and attitude of students in a third year Cellular Physiology unit after use of interactive online cellular diffusion modules modified for the Australian context. The modules have been designed to integrate QS into the biological science curriculum using familiar scenarios and informal language and providing students with the opportunity to review solutions to diffusion QS-related problems with interactive graphics. This paper will discuss results of pre and post MathBench quizzes composed of general and module specific questions that assessed change in student QS after MathBench; and pre and post surveys, administered before and after using MathBench modules to evaluate the students’ change in perception towards the influence of the modules, their attitude towards QS and on the development of their confidence in completing the inquiry-based activity as well as changes to their appreciation of the relevance of mathematics to cellular processes. Results will be compared to changes reported by Thompson et al., (2010) at the University of Maryland and implications for further integration of interactive online activities in the curriculum will be explored and discussed.

Keywords: quantitative skills, MathBench, maths in biology

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99 The Impact of Oxytetracycline on the Aquaponic System, Biofilter, and Plants

Authors: Hassan Alhoujeiri, Angele Matrat, Sandra Beaufort, Claire joaniss Cassan, Jerome Silvester

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Aquaponics is a sustainable food production technology, and its transition to industrial-scale systems has created several challenges that require further investigation in order to make it a robust process. One of the critical concerns is the potential accumulation of compounds from veterinary treatments, phytosanitary agents, fish feed, or simply from contaminated water sources. The accumulation of these substances could negatively impact fish health, microbial biofilters, and plant growth, thereby disrupting the system’s overall balance and functionality. The lack of legislation and knowledge regarding the presence of such compounds in aquaponic systems raises concerns about their potential impact on both system balance and food safety. In this study, we focused on the effects of oxytetracycline (OTC), an antibiotic commonly used in aquaculture, on both the microbial biofilter and plant growth. Although OTC is rarely applied in aquaponics today, the fish compartment may need to be isolated from the system during treatment, as it inhibits specific bacterial populations, which could affect the microbial biofilter's efficiency. However, questions remain about the aquaponic system's tolerance threshold, particularly in cases of treatment or residual OTC traces post-treatment. This study results indicated a decline in microbial biofilter activity to 20% compared to the control, potentially corresponding to treatments of 41 mg/L of OTC. Analysis of microbial populations in the biofilter, using flow cytometry and microscopy (confocal and scanning electron microscopy), revealed an increase in bacterial mortality without disrupting the microbial biofilm. Additionally, OTC exposure led to noticeable changes in plant morphology (e.g., color) and growth, though it did not fully inhibit development. However, no significant effects were observed on seed germination at the tested concentrations despite a measurable impact on subsequent plant growth.

Keywords: aquaponic, oxytetracycline, nitrifying biofilter, plant, micropollutants, sustainability

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98 Eco-Fashion Dyeing of Denim and Knitwear with Particle-Dyes

Authors: Adriana Duarte, Sandra Sampaio, Catia Ferreira, Jaime I. N. R. Gomes

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With the fashion of faded worn garments the textile industry has moved from indigo and pigments to dyes that are fixed by cationization, with products that can be toxic, and that can show this effect after washing down the dye with friction and/or treating with enzymes in a subsequent operation. Increasingly they are treated with bleaches, such as hypochlorite and permanganate, both toxic substances. An alternative process is presented in this work for both garment and jet dyeing processes, without the use of pre-cationization and the alternative use of “particle-dyes”. These are hybrid products, made up by an inorganic particle and an organic dye. With standard soluble dyes, it is not possible to avoid diffusion into the inside of the fiber unless using previous cationization. Only in this way can diffusion be avoided keeping the centre of the fibres undyed so as to produce the faded effect by removing the surface dye and showing the white fiber beneath. With “particle-dyes”, previous cationization is avoided. By applying low temperatures, the dye does not diffuse completely into the inside of the fiber, since it is a particle and not a soluble dye, being then able to give the faded effect. Even though bleaching can be used it can also be avoided, by the use of friction and enzymes they can be used just as for other dyes. This fashion brought about new ways of applying reactive dyes by the use of previous cationization of cotton, lowering the salt, and temperatures that reactive dyes usually need for reacting and as a side effect the application of a more environmental process. However, cationization is a process that can be problematic in applying it outside garment dyeing, such as jet dyeing, being difficult to obtain level dyeings. It also should be applied by a pad-fix or Pad-batch process due to the low affinity of the pre-cationization products making it a more expensive process, and the risk of unlevelness in processes such as jet dyeing. Wit particle-dyes, since no pre-cationizartion is necessary, they can be applied in jet dyeing. The excess dye is fixed by a fixing agent, fixing the insoluble dye onto the surface of the fibers. By applying the fixing agent only one to 1-3 rinses in water at room temperature are necessary, saving water and improving the washfastness.

Keywords: denim, garment dyeing, worn look, eco-fashion

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97 Drug-Based Nanoparticles: Comparative Study of the Effect Drug Type on Release Kinetics and Cell Viability

Authors: Chukwudalu C. Nwazojie, Wole W. Soboyejo, John Obayemi, Ali Salifu Azeko, Sandra M. Jusu, Chinyerem M. Onyekanne

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The conventional methods for the diagnosis and treatment of breast cancer include bulk systematic mammography, ultrasound, dynamic contrast-enhanced fast 3D gradient-echo (GRE) magnetic resonance imaging (MRI), surgery, chemotherapy, and radiotherapy. However, nanoparticles and drug-loaded polymer microspheres for disease (cancer) targeting and treatment have enormous potential to enhance the approaches that are used today. The goal is to produce an implantable biomedical device for localized breast cancer drug delivery within Africa and the world. The main advantage of localized delivery is that it reduces the amount of drug that is needed to have a therapeutic effect. Polymer blends of poly (D,L-lactide-co-glycolide) (PLGA) and polycaprolactone (PCL), which are biodegradable, is used as a drug excipient. This work focuses on the development of PLGA-PCL (poly (D,L-lactide-co-glycolide) (PLGA) blended with based injectable drug microspheres and are loaded with anticancer drugs (prodigiosin (PG), and paclitaxel (PTX) control) and also the conjugated forms of the drug functionalized with LHRH (luteinizing hormone-releasing hormone) (PG-LHRH, and PTX- LHRH control), using a single-emulsion solvent evaporation technique. The encapsulation was done in the presence of PLGA-PCL (as a polymer matrix) and poly-(vinyl alcohol) (PVA) (as an emulsifier). Comparative study of the various drugs release kinetics and degradation mechanisms of the PLGA-PCL with an encapsulated drug is achieved, and the implication of this study is for the potential application of prodigiosin PLGA-PCL loaded microparticles for controlled delivery of cancer drug and treatment to prevent the regrowth or locoregional recurrence, following surgical resection of triple-negative breast tumor.

Keywords: cancer, polymers, drug kinetics, nanoparticles

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96 Advanced Technology for Natural Gas Liquids (NGL) Recovery Using Residue Gas Split

Authors: Riddhiman Sherlekar, Umang Paladia, Rachit Desai, Yash Patel

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The competitive scenario of the oil and gas market is a challenge for today’s plant designers to achieve designs that meet client expectations with shrinking budgets, safety requirements, and operating flexibility. Natural Gas Liquids have three main industrial uses. They can be used as fuels, or as petrochemical feedstock or as refinery blends that can be further processed and sold as straight run cuts, such as naphtha, kerosene and gas oil. NGL extraction is not a chemical reaction. It involves the separation of heavier hydrocarbons from the main gas stream through pressure as temperature reduction, which depending upon the degree of NGL extraction may involve cryogenic process. Previous technologies i.e. short cycle dry desiccant absorption, Joule-Thompson or Low temperature refrigeration, lean oil absorption have been giving results of only 40 to 45% ethane recoveries, which were unsatisfying depending upon the current scenario of down turn market. Here new technology has been suggested for boosting up the recoveries of ethane+ up to 95% and up to 99% for propane+ components. Cryogenic plants provide reboiling to demethanizers by using part of inlet feed gas, or inlet feed split. If the two stream temperatures are not similar, there is lost work in the mixing operation unless the designer has access to some proprietary design. The concept introduced in this process consists of reboiling the demethanizer with the residue gas, or residue gas split. The innovation of this process is that it does not use the typical inlet gas feed split type of flow arrangement to reboil the demethanizer or deethanizer column, but instead uses an open heat pump scheme to that effect. The residue gas compressor provides the heat pump effect. The heat pump stream is then further cooled and entered in the top section of the column as a cold reflux. Because of the nature of this design, this process offers the opportunity to operate at full ethane rejection or recovery. The scheme is also very adaptable to revamp existing facilities. This advancement can be proven not only in enhancing the results but also provides operational flexibility, optimize heat exchange, introduces equipment cost reduction, opens a future for the innovative designs while keeping execution costs low.

Keywords: deethanizer, demethanizer, residue gas, NGL

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95 Consumers’ Willingness to Pay for Organic Vegetables in Oyo State

Authors: Olanrewaju Kafayat, O., Salman Kabir, K.

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The role of organic agriculture in providing food and income is now gaining wider recognition (Van Elzakker et al 2007). The increasing public concerns about food safety issues on the use of fertilizers, pesticide residues, growth hormones, GM organisms, and increasing awareness of environmental quality issues have led to an expanding demand for environmentally friendly products (Thompson, 1998; Rimal et al., 2005). As a result national governments are concerned about diet and health, and there has been renewed recognition of the role of public policy in promoting healthy diets, thus to provide healthier, safer, more confident citizens (Poole et al., 2007), With these benefits, a study into organic vegetables is very vital to all the major stakeholders. This study analyzed the willingness of consumers to pay for organic vegetables in Oyo state, Nigeria. Primary data was collected with the aid of structured questionnaire administered to 168 respondents. These were selected using multistage random sampling. The first stage involved the selection two (2) ADP zones out of the three (3) ADP zones in Oyo state, The second stage involved the random selection of two (2) local government areas each out of the two (2) ADP zones which are; Ibadan South West and Ogbomoso North and random selection of 4 wards each from the local government areas. The third stage involved random selection of 42 household each from of the local government areas. Descriptive statistics, the principal component analysis, and the logistic regression were used to analyze the data. Results showed 55 percent of the respondents were female while 80 percent were  50 years. 74 percent of the respondents agreed that organic vegetables are of better quality. 31 percent of the respondents were aware of organic vegetables as against 69 percent who were not aware. From the logistic model, educational attainment, amount spent on organic vegetables monthly, better quality of organic vegetables and accessibility to organic vegetables were significant and had a positive relationship on willingness to pay for organic vegetable. The variables that were significant and had a negative relationship with WTP are less attractiveness of organic vegetables and household size of the respondents. This study concludes that consumers with higher level of education were more likely to be aware and willing to pay for organic vegetables than those with low levels of education, the study therefore recommends creation of awareness on the relevance of consuming organic vegetables through effective marketing and educational campaigns.

Keywords: consumers awareness, willingness to pay, organic vegetables, Oyo State

Procedia PDF Downloads 273
94 Detection and Classification Strabismus Using Convolutional Neural Network and Spatial Image Processing

Authors: Anoop T. R., Otman Basir, Robert F. Hess, Eileen E. Birch, Brooke A. Koritala, Reed M. Jost, Becky Luu, David Stager, Ben Thompson

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Strabismus refers to a misalignment of the eyes. Early detection and treatment of strabismus in childhood can prevent the development of permanent vision loss due to abnormal development of visual brain areas. We developed a two-stage method for strabismus detection and classification based on photographs of the face. The first stage detects the presence or absence of strabismus, and the second stage classifies the type of strabismus. The first stage comprises face detection using Haar cascade, facial landmark estimation, face alignment, aligned face landmark detection, segmentation of the eye region, and detection of strabismus using VGG 16 convolution neural networks. Face alignment transforms the face to a canonical pose to ensure consistency in subsequent analysis. Using facial landmarks, the eye region is segmented from the aligned face and fed into a VGG 16 CNN model, which has been trained to classify strabismus. The CNN determines whether strabismus is present and classifies the type of strabismus (exotropia, esotropia, and vertical deviation). If stage 1 detects strabismus, the eye region image is fed into stage 2, which starts with the estimation of pupil center coordinates using mask R-CNN deep neural networks. Then, the distance between the pupil coordinates and eye landmarks is calculated along with the angle that the pupil coordinates make with the horizontal and vertical axis. The distance and angle information is used to characterize the degree and direction of the strabismic eye misalignment. This model was tested on 100 clinically labeled images of children with (n = 50) and without (n = 50) strabismus. The True Positive Rate (TPR) and False Positive Rate (FPR) of the first stage were 94% and 6% respectively. The classification stage has produced a TPR of 94.73%, 94.44%, and 100% for esotropia, exotropia, and vertical deviations, respectively. This method also had an FPR of 5.26%, 5.55%, and 0% for esotropia, exotropia, and vertical deviation, respectively. The addition of one more feature related to the location of corneal light reflections may reduce the FPR, which was primarily due to children with pseudo-strabismus (the appearance of strabismus due to a wide nasal bridge or skin folds on the nasal side of the eyes).

Keywords: strabismus, deep neural networks, face detection, facial landmarks, face alignment, segmentation, VGG 16, mask R-CNN, pupil coordinates, angle deviation, horizontal and vertical deviation

Procedia PDF Downloads 96
93 Vineyard Soils of Karnataka - Characterization, Classification and Soil Site Suitability Evaluation

Authors: Harsha B. R., K. S. Anil Kumar

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Land characterization, classification, and soil suitability evaluation of grapes-growing pedons were assessed at fifteen taluks covering four agro climatic zones of Karnataka. Study on problems and potentials of grapes cultivation in selected agro-climatic zones was carried out along with the plant sample analysis. Twenty soil profiles were excavated as study site based on the dominance of area falling under grapes production and existing spatial variability of soils. The detailed information of profiles and horizon wise soil samples were collected to study the morphological, physical, chemical, and fertility characteristics. Climatic analysis and water retention characteristics of soils of major grapes-growing areas were also done. Based on the characterisation and classification study, it was revealed that soils of Doddaballapur (Bangalore Blue and Wine grapes), Bangalore North (GKVK Farm, Rajankunte, and IIHR Farm), Devanahalli, Magadi, Hoskote, Chikkaballapur (Dilkush and Red globe), Yelaburga, Hagari Bommanahalli, Bagalkot (UHS farm) and Indi fall under the soil order Alfisol. Vijaypur pedon of northern dry zone was keyed out as Vertisols whereas, Jamkhandi and Athani as Inceptisols. Properties of Aridisols were observed in B. Bagewadi (Manikchaman and Thompson Seedless) and Afzalpur. Soil fertility status and its mapping using GIS technique revealed that all the nutrients were found to be in adequate range except nitrogen, potassium, zinc, iron, and boron, which indicated the need for application along with organic matter to improve the SOC status. Varieties differed among themselves in yield and plant nutrient composition depending on their age, climatic, soil, and management requirements. Bangalore North (GKVK farm) and Jamkhandi are having medium soil organic carbon stocks of 6.21 and 6.55 kg m⁻³, respectively. Soils of Bangalore North (Rajankunte) were highly suitable (S1) for grapes cultivation. Under northern Karnataka, Vijayapura, B. Bagewadi, Indi, and Afzalpur vineyards were good performers despite the limitations of fertility and free lime content.

Keywords: land characterization, suitability, soil orders, soil organic carbon stock

Procedia PDF Downloads 114
92 Women’s Financial Literacy and Family Financial Fragility

Authors: Pepur Sandra, Bulog Ivana, Rimac Smiljanić Ana

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During the COVID-19 pandemic, stress and family financial fragility arose worldwide. Economic and health uncertainty created new pressure on the everyday life of families. The work from home, homeschooling, and care of other family members caused an increase in unpaid work and generated a new division of intrahousehold. As many times before, women have taken the higher burden. This paper analyzes family stress and finance during the COVID-19 pandemic. We propose that women's inclusion in paid and unpaid work and their financial literacy influence family finances. We build up our assumptions according to the two theories that explain intrahousehold family decision-making: traditional and barging models. The traditional model assumes that partners specialize in their roles in line with time availability. Consequently, partners less engaged in payable working activities will spend more time on domestic activities and vice versa. According to the bargaining model, each individual has their preferences, and the one with more household bargaining power, e.g., higher income, higher level of education, better employment, or higher financial knowledge, is likely to make family decisions and avoid unpaid work. Our results are based on an anonymous and voluntary survey of 869 valid responses from women older than 18 conducted in Croatia at the beginning of 2021. We found that families who experienced delays in settling current obligations before the pandemic were in a worse financial situation during the pandemic. However, all families reported problems settling current obligations during pandemic times regardless of their financial condition before the crisis. Women from families with financial issues reported higher levels of family and personal stress during the pandemic. Furthermore, we provide evidence that more women's unpaid work negatively affects the family's financial fragility during the pandemic. In addition, in families where women have better financial literacy and are more financially independent, families cope better with finance before and during pandemics.

Keywords: family financial fragility, stress, unpaid work, women's financial literacy

Procedia PDF Downloads 80
91 Towards Innovation Performance among University Staff

Authors: Cheng Sim Quah, Sandra Phek Lin Sim

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This study examined how individuals in their respective teams contributed to innovation performance besides defining the term of innovation in their own respective views. This study also identified factors that motivated University staff to contribute to the innovation products. In addition, it examined whether there is a significant relationship between professional training level and the length of service among university staff towards innovation and to what extent do the two variables contributed towards innovative products. The significance of this study is that it revealed the strengths and weaknesses of the university staff when contributing to innovation performance. Stratified-random sampling was employed to determine the samples representing the population of lecturers in the study, involving 123 lecturers in one of the local universities in Malaysia. The method employed to analyze the data is through categorizing into themes for the open-ended questions besides using descriptive and inferential statistics for the quantitative data. This study revealed that two types of definition for the term “innovation” exist among the university staff, namely, creation of new product or new approach to do things as well as value-added creative way to upgrade or improve existing process and service to be more efficient. This study found that the most prominent factor that propel them towards innovation is to improve the product in order to benefit users, followed by self-satisfaction and recognition. This implies that the staff in the organization viewed the creation of innovative products as a process of growth to fulfill the needs of others and also to realize their personal potential. This study also found that there was only a significant relationship between the professional training level and the length of service of 4-6 years among the university staff. The rest of the groups based on the length of service showed that there was no significant relationship with the professional training level towards innovation. Moreover, results of the study on directional measures depicted that the relationship for the length of service of 4 - 6 years with professional training level among the university staff is quite weak. This implies that good organization management lies on the shoulders of the key leaders who enlighten the path to be followed by the staff.

Keywords: innovation, length of service, performance, professional training level, motivation

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90 Zero Energy Buildings in Hot-Humid Tropical Climates: Boundaries of the Energy Optimization Grey Zone

Authors: Nakul V. Naphade, Sandra G. L. Persiani, Yew Wah Wong, Pramod S. Kamath, Avinash H. Anantharam, Hui Ling Aw, Yann Grynberg

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Achieving zero-energy targets in existing buildings is known to be a difficult task requiring important cuts in the building energy consumption, which in many cases clash with the functional necessities of the building wherever the on-site energy generation is unable to match the overall energy consumption. Between the building’s consumption optimization limit and the energy, target stretches a case-specific optimization grey zone, which requires tailored intervention and enhanced user’s commitment. In the view of the future adoption of more stringent energy-efficiency targets in the context of hot-humid tropical climates, this study aims to define the energy optimization grey zone by assessing the energy-efficiency limit in the state-of-the-art typical mid- and high-rise full AC office buildings, through the integration of currently available technologies. Energy models of two code-compliant generic office-building typologies were developed as a baseline, a 20-storey ‘high-rise’ and a 7-storey ‘mid-rise’. Design iterations carried out on the energy models with advanced market ready technologies in lighting, envelope, plug load management and ACMV systems and controls, lead to a representative energy model of the current maximum technical potential. The simulations showed that ZEB targets could be achieved in fully AC buildings under an average of seven floors only by compromising on energy-intense facilities (as full AC, unlimited power-supply, standard user behaviour, etc.). This paper argues that drastic changes must be made in tropical buildings to span the energy optimization grey zone and achieve zero energy. Fully air-conditioned areas must be rethought, while smart technologies must be integrated with an aggressive involvement and motivation of the users to synchronize with the new system’s energy savings goal.

Keywords: energy simulation, office building, tropical climate, zero energy buildings

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89 Using Nature-Based Solutions to Decarbonize Buildings in Canadian Cities

Authors: Zahra Jandaghian, Mehdi Ghobadi, Michal Bartko, Alex Hayes, Marianne Armstrong, Alexandra Thompson, Michael Lacasse

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The Intergovernmental Panel on Climate Change (IPCC) report stated the urgent need to cut greenhouse gas emissions to avoid the adverse impacts of climatic changes. The United Nations has forecasted that nearly 70 percent of people will live in urban areas by 2050 resulting in a doubling of the global building stock. Given that buildings are currently recognised as emitting 40 percent of global carbon emissions, there is thus an urgent incentive to decarbonize existing buildings and to build net-zero carbon buildings. To attain net zero carbon emissions in communities in the future requires action in two directions: I) reduction of emissions; and II) removal of on-going emissions from the atmosphere once de-carbonization measures have been implemented. Nature-based solutions (NBS) have a significant role to play in achieving net zero carbon communities, spanning both emission reductions and removal of on-going emissions. NBS for the decarbonisation of buildings can be achieved by using green roofs and green walls – increasing vertical and horizontal vegetation on the building envelopes – and using nature-based materials that either emit less heat to the atmosphere thus decreasing photochemical reaction rates, or store substantial amount of carbon during the whole building service life within their structure. The NBS approach can also mitigate urban flooding and overheating, improve urban climate and air quality, and provide better living conditions for the urban population. For existing buildings, de-carbonization mostly requires retrofitting existing envelopes efficiently to use NBS techniques whereas for future construction, de-carbonization involves designing new buildings with low carbon materials as well as having the integrity and system capacity to effectively employ NBS. This paper presents the opportunities and challenges in respect to the de-carbonization of buildings using NBS for both building retrofits and new construction. This review documents the effectiveness of NBS to de-carbonize Canadian buildings, identifies the missing links to implement these techniques in cold climatic conditions, and determine a road map and immediate approaches to mitigate the adverse impacts of climate change such as urban heat islanding. Recommendations are drafted for possible inclusion in the Canadian building and energy codes.

Keywords: decarbonization, nature-based solutions, GHG emissions, greenery enhancement, buildings

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88 Regional Anesthesia in Carotid Surgery: A Single Center Experience

Authors: Daniel Thompson, Muhammad Peerbux, Sophie Cerutti, Hansraj Riteesh Bookun

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Patients with carotid stenosis, which may be asymptomatic or symptomatic in the form of transient ischaemic attack (TIA), amaurosis fugax, or stroke, often require an endarterectomy to reduce stroke risk. Risks of this procedure include stroke, death, myocardial infarction, and cranial nerve damage. Carotid endarterectomy is most commonly performed under general anaesthetic, however, it can also be undertaken with a regional anaesthetic approach. Our tertiary centre generally performs carotid endarterectomy under regional anaesthetic. Our major tertiary hospital mostly utilises regional anaesthesia for carotid endarterectomy. We completed a cross-sectional analysis of all cases of carotid endarterectomy performed under regional anaesthesia across a 10-year period between January 2010 to March 2020 at our institution. 350 patients were included in this descriptive analysis, and demographic details for patients, indications for surgery, procedural details, length of surgery, and complications were collected. Data was cross tabulated and presented in frequency tables to describe these categorical variables. 263 of the 350 patients in the analysis were male, with a mean age of 71 ± 9. 172 patients had a history of ischaemic heart disease, 104 had diabetes mellitus, 318 had hypertension, and 17 patients had chronic kidney disease greater than Stage 3. 13.1% (46 patients) were current smokers, and the majority (63%) were ex-smokers. Most commonly, carotid endarterectomy was performed conventionally with patch arterioplasty 96% of the time (337 patients). The most common indication was TIA and stroke in 64% of patients, 18.9% were classified as asymptomatic, and 13.7% had amaurosis fugax. There were few general complications, with 9 wound complications/infections, 7 postoperative haematomas requiring return to theatre, 3 myocardial infarctions, 3 arrhythmias, 1 exacerbation of congestive heart failure, 1 chest infection, and 1 urinary tract infection. Specific complications to carotid endarterectomy included 3 strokes, 1 postoperative TIA, and 1 cerebral bleed. There were no deaths in our cohort. This analysis of a large cohort of patients from a major tertiary centre who underwent carotid endarterectomy under regional anaesthesia indicates the safety of such an approach for these patients. Regional anaesthesia holds the promise of less general respiratory and cardiac events compared to general anaesthesia, and in this vulnerable patient group, calls for comparative research between local and general anaesthesia in carotid surgery.

Keywords: anaesthesia, carotid endarterectomy, stroke, carotid stenosis

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87 Diaper Dermatitis and Pancytopenia as the Primary Manifestation in an Infant with Vitamin B12 Deficiency

Authors: Ekaterina Sánchez Romero, Emily Gabriela Aguirre Herrera, Sandra Luz Espinoza Esquerra, Jorge García Campos

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Female, 7 months old, daughter of a mother with anemia during pregnancy, with no history of atopy in the family, since birth she presents with recurrent dermatological and gastrointestinal infections, chronically treated for recurrent diaper dermatitis. At 6 months of age, she begins with generalized pallor, hyperpigmentation in hands and feet, smooth tongue, psychomotor retardation with lack of head support, sedation, and hypoactivity. She was referred to our hospital for a fever of 38°C, severe diaper rash, and pancytopenia with HB 9.3, platelets 38000, neutrophils 0.39 MCV: 86.80 high for her age. The approach was initiated to rule out myeloproliferative syndrome, with negative immunohistochemical results of bone marrow aspirate; during her stay, she presented neurological regression, lack of sucking, and focal seizures. CT scan showed cortical atrophy. The patient was diagnosed with primary immunodeficiency due to history; gamma globulin was administered without improvement with normal results of immunoglobulins and metabolic screening. When dermatological and neurological diagnoses were ruled out as the primary cause, a nutritional factor was evaluated, and a therapeutic trial was started with the administration of vitamin B12 and zinc, presenting clinical neurological improvement and resolution of pancytopenia in 2 months. It was decided to continue outpatient management. Discussion: We present a patient with neurological, dermatological involvement, and pancytopenia, so the most common differential diagnoses in this population were ruled out. Vitamin B12 deficiency is an uncommon entity. Due to maternal and clinical history, a therapeutic trial was started resulting in an improvement. Conclusion: VitaminB12 deficiency should be considered one of the differential diagnoses in the approach to pancytopenia with megaloblastic anemia associated with dermatologic and neurologic manifestations. Early treatment can reduce irreversible damage in these patients.

Keywords: vitamin B12 deficiency, pediatrics, pancytopenia, diaper dermatitis

Procedia PDF Downloads 99
86 Demarcating Wetting States in Pressure-Driven Flows by Poiseuille Number

Authors: Anvesh Gaddam, Amit Agrawal, Suhas Joshi, Mark Thompson

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An increase in surface area to volume ratio with a decrease in characteristic length scale, leads to a rapid increase in pressure drop across the microchannel. Texturing the microchannel surfaces reduce the effective surface area, thereby decreasing the pressured drop. Surface texturing introduces two wetting states: a metastable Cassie-Baxter state and stable Wenzel state. Predicting wetting transition in textured microchannels is essential for identifying optimal parameters leading to maximum drag reduction. Optical methods allow visualization only in confined areas, therefore, obtaining whole-field information on wetting transition is challenging. In this work, we propose a non-invasive method to capture wetting transitions in textured microchannels under flow conditions. To this end, we tracked the behavior of the Poiseuille number Po = f.Re, (with f the friction factor and Re the Reynolds number), for a range of flow rates (5 < Re < 50), and different wetting states were qualitatively demarcated by observing the inflection points in the f.Re curve. Microchannels with both longitudinal and transverse ribs with a fixed gas fraction (δ, a ratio of shear-free area to total area) and at a different confinement ratios (ε, a ratio of rib height to channel height) were fabricated. The measured pressure drop values for all the flow rates across the textured microchannels were converted into Poiseuille number. Transient behavior of the pressure drop across the textured microchannels revealed the collapse of liquid-gas interface into the gas cavities. Three wetting states were observed at ε = 0.65 for both longitudinal and transverse ribs, whereas, an early transition occurred at Re ~ 35 for longitudinal ribs at ε = 0.5, due to spontaneous flooding of the gas cavities as the liquid-gas interface ruptured at the inlet. In addition, the pressure drop in the Wenzel state was found to be less than the Cassie-Baxter state. Three-dimensional numerical simulations confirmed the initiation of the completely wetted Wenzel state in the textured microchannels. Furthermore, laser confocal microscopy was employed to identify the location of the liquid-gas interface in the Cassie-Baxter state. In conclusion, the present method can overcome the limitations posed by existing techniques, to conveniently capture wetting transition in textured microchannels.

Keywords: drag reduction, Poiseuille number, textured surfaces, wetting transition

Procedia PDF Downloads 161
85 Structural Correlates of Reduced Malicious Pleasure in Huntington's Disease

Authors: Sandra Baez, Mariana Pino, Mildred Berrio, Hernando Santamaria-Garcia, Lucas Sedeno, Adolfo Garcia, Sol Fittipaldi, Agustin Ibanez

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Schadenfreude refers to the perceiver’s experience of pleasure at another’s misfortune. This is a multidetermined emotion which can be evoked by hostile feelings and envy. The experience of Schadenfreude engages mechanisms implicated in diverse social cognitive processes. For instance, Schadenfreude involves heightened reward processing, accompanied by increased striatal engagement and it interacts with mentalizing and perspective-taking abilities. Patients with Huntington's disease (HD) exhibit reductions of Schadenfreude experience, suggesting a role of striatal degeneration in such an impairment. However, no study has directly assessed the relationship between regional brain atrophy in HD and reduced Schadenfreude. This study investigated whether gray matter (GM) atrophy in HD patients correlates with ratings of Schadenfreude. First, we compared the performance of 20 HD patients and 23 controls on an experimental task designed to trigger Schadenfreude and envy (another social emotion acting as a control condition). Second, we compared GM volume between groups. Third, we examined brain regions where atrophy might be associated with specific impairments in the patients. Results showed that while both groups showed similar ratings of envy, HD patients reported lower Schadenfreude. The latter pattern was related to atrophy in regions of the reward system (ventral striatum) and the mentalizing network (precuneus and superior parietal lobule). Our results shed light on the intertwining of reward and socioemotional processes in Schadenfreude, while offering novel evidence about their neural correlates. In addition, our results open the door to future studies investigating social emotion processing in other clinical populations characterized by striatal or mentalizing network impairments (e.g., Parkinson’s disease, schizophrenia, autism spectrum disorders).

Keywords: envy, Gray matter atrophy, Huntigton's disease, Schadenfreude, social emotions

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84 A Serum- And Feeder-Free Culture System for the Robust Generation of Human Stem Cell-Derived CD19+ B Cells and Antibody-Secreting Cells

Authors: Kirsten Wilson, Patrick M. Brauer, Sandra Babic, Diana Golubeva, Jessica Van Eyk, Tinya Wang, Avanti Karkhanis, Tim A. Le Fevre, Andy I. Kokaji, Allen C. Eaves, Sharon A. Louis, , Nooshin Tabatabaei-Zavareh

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Long-lived plasma cells are rare, non-proliferative B cells generated from antibody-secreting cells (ASCs) following an immune response to protect the host against pathogen re-exposure. Despite their therapeutic potential, the lack of in vitro protocols in the field makes it challenging to use B cells as a cellular therapeutic tool. As a result, there is a need to establish robust and reproducible methods for the generation of B cells. To address this, we have developed a culture system for generating B cells from hematopoietic stem and/or progenitor cells (HSPCs) derived from human umbilical cord blood (CB) or pluripotent stem cells (PSCs). HSPCs isolated from CB were cultured using the StemSpan™ B Cell Generation Kit and produced CD19+ B cells at a frequency of 23.2 ± 1.5% and 59.6 ± 2.3%, with a yield of 91 ± 11 and 196 ± 37 CD19+ cells per input CD34+ cell on culture days 28 and 35, respectively (n = 50 - 59). CD19+IgM+ cells were detected at a frequency of 31.2 ± 2.6% and were produced at a yield of 113 ± 26 cells per input CD34+ cell on culture day 35 (n = 50 - 59). The B cell receptor loci of CB-derived B cells were sequenced to confirm V(D)J gene rearrangement. ELISpot analysis revealed that ASCs were generated at a frequency of 570 ± 57 per 10,000 day 35 cells, with an average IgM+ ASC yield of 16 ± 2 cells per input CD34+ cell (n = 33 - 42). PSC-derived HSPCs were generated using the STEMdiff™ Hematopoietic - EB reagents and differentiated to CD10+CD19+ B cells with a frequency of 4 ± 0.8% after 28 days of culture (n = 37, 1 embryonic and 3 induced pluripotent stem cell lines tested). Subsequent culture of PSC-derived HSPCs increased CD19+ frequency and generated ASCs from 1 - 2 iPSC lines. This method is the first report of a serum- and feeder-free system for the generation of B cells from CB and PSCs, enabling further B lineage-specific research for potential future clinical applications.

Keywords: stem cells, B cells, immunology, hematopoiesis, PSC, differentiation

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83 Ergonomic Adaptations in Visually Impaired Workers - A Literature Review

Authors: Kamila Troper, Pedro Mestre, Maria Lurdes Menano, Joana Mendonça, Maria João Costa, Sandra Demel

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Introduction: Visual impairment is a problem that has an influence on hundreds of thousands of people all over the world. Although it is possible for a Visually Impaired person to do most jobs, the right training, technological assistance, and emotional support are essential. Ergonomics be able to solve many of the problems/issues with the relative ease of positioning, lighting and design of the workplace. A little forethought can make a tremendous difference to the ease with which a person with an impairment function. Objectives: Review the main ergonomic adaptation measures reported in the literature in order to promote better working conditions and safety measures for the visually impaired. Methodology: This was an exploratory-descriptive, qualitative literature systematic review study. The main databases used were: PubMed, BIREME, LILACS, with articles and studies published between 2000 and 2021. Results: Based on the principles of the theoretical references of ergonomic analysis of work, the main restructuring of the physical space of the workstations were: Accessibility facilities and assistive technologies; A screen reader that captures information from a computer and sends it in real-time to a speech synthesizer or Braille terminal; Installations of software with voice recognition, Monitors with enlarged screens; Magnification software; Adequate lighting, magnifying lenses in addition to recommendations regarding signage and clearance of the places where the visually impaired pass through. Conclusions: Employability rates for people with visual impairments(both those who are blind and those who have low vision)are low and continue to be a concern to the world and for researchers as a topic of international interest. Although numerous authors have identified barriers to employment and proposed strategies to remediate or circumvent those barriers, people with visual impairments continue to experience high rates of unemployment.

Keywords: ergonomic adaptations, visual impairments, ergonomic analysis of work, systematic review

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82 Comparison of Maternal and Perinatal Outcomes of Obstetric Population Diagnosed with Covid-19 in Reference to Influenza A/H1N1: A Systematic Review and Meta-Analysis

Authors: Maria Vargas Hernandez, Jose Rojas Suarez, Carmelo Dueñas Castell, Sandra Contreras, Camilo Bello, Diana Borre, Walter Anichiarico, Harold Vasquez, Eduard Perez, Jose Santacruz

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In the last two decades, there have been outbreaks of emerging infectious diseases, with an impact on both the general population and the obstetric population. These infections, which affect the general population, pose a high risk for adverse maternal and perinatal outcomes, taking into account that physiological and immunological changes that occur during pregnancy can increase their risk or severity. Among these, the pandemics of viral infections, Influenza A/H1N1 and SARS-CoV-2/COVID-19, stand out. In 2009, Influenza A/H1N1 infection (H1N1 2009pdm) affected approximately 3,110 obstetric patients, with data reported from 29 countries, including 1,625 (52.3%) cases that were hospitalized, 378 (23.3%) admissions to ICU and 130 (8%) deaths; and since the end of 2019, the Severe Acute Respiratory Syndrome - 2 (SARS-CoV-2) has been identified, causing the COVID-19 pandemic, with global mortality that is around 2-4% for the general population, and higher mortality in patients requiring admission to the intensive care unit. Its impact on the obstetric population is still unknown. Objectives: To evaluate the impact on maternal and perinatal outcomes of COVID-19 infection in reference to influenza A/H1N1 infection in the obstetric population. Methodology: Systematic review of the literature and meta-analysis. Results: Mortality from maternal infection with influenza A/H1N1 appears to be higher (8%) than mortality due to maternal infection with COVID-19 (3%). The rates of ICU admission, hospitalization, the requirement for invasive mechanical ventilation, and fetal death also appear to be higher in the maternal population with A/H1N1 infection, in reference to the maternal population with COVID-19 infection. Within perinatal outcomes, the admission to the neonatal ICU appears to be higher in the infants born to mothers with COVID-19 infection (28% vs. 15% for COVID-19 and A/H1N1, respectively). Conclusion: A/H1N1 infection in the obstetric population seems to be associated with a higher proportion of adverse outcomes in relation to COVID-19 infection. The actual impact of maternal influenza A/H1N1 infection on perinatal outcomes is unknown. More COVID-19 studies are needed to understand the impact of maternal infection on perinatal outcomes in this population.

Keywords: A/H1N1, COVID-19, maternal outcomes, perinatal outcomes

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