Search results for: epidemiological study

Authors: Ahmad Umar, Ahmed A. Ibrahim, Mohsen A. Alhamami

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This study introduces a facile synthesis method for synthesizing reduced graphene oxide (rGO) nanosheets with surface decoration of polyaniline (PANI). The resultant rGO@PANI nanocomposite (NC) exhibit substantial potential as advanced electrode materials for high-performance supercapacitors. The strategic integration of PANI onto the rGO surface serves dual purposes, effectively mitigating the agglomeration of rGO films and augmenting their utility in supercapacitor applications. The PANI coating manifests a highly porous and nanosized morphology, fostering increased surface area and optimized mass transport by reducing diffusion kinetics. The nanosized structure of PANI contributes to the maximization of active sites, thereby bolstering the efficacy of the nanocomposites for diverse applications. The inherent conductive nature of the rGO surface significantly expedites electron transport, thereby amplifying the overall electrochemical performance of the nanocomposites. To systematically evaluate the influence of PANI concentration on the electrode performance, varying concentrations of PANI were incorporated. Notably, an elevated PANI concentration was found to enhance the response owing to the unique morphology of PANI. Remarkably, the 5% rGO@PANI NC emerged as the most promising candidate, demonstrating exceptional response characteristics with a specific capacitance of 314.2 F/g at a current density of 1 A/g. Furthermore, this catalyst exhibits outstanding long-term stability, retaining approximately 92% of its capacitance even after enduring 4000 cycles. This research underscores the significance of the synergistic integration of rGO and PANI in the design of high-performance supercapacitors. The elucidation of the underlying mechanisms governing the improved electrochemical properties contributes to the fundamental understanding of nanocomposite behavior, thereby paving the way for the rational design of next-generation energy storage materials.

Keywords: reduced graphene oxide, polyaniline, nanocomposites, supercapacitors, energy storage

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Authors: E. N. Vetrova, L.V. Lapochkina, N. V. Nikulina

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In the national economy, entrepreneurship plays the role of a buffer between economy and policy for it contributes to improving budget effectiveness and decreasing dependence of economy on the state. Entrepreneurship in industry makes it possible to increase the added value that is formed in production chains and to decrease dependence on import. Under the current circumstances, when sanctions are being imposed, this is especially relevant for Russia and for the realization of projects in the Russian Arctic. However, development of entrepreneurship in industry requires an enlightened state policy. The purpose of the research is elaboration of recommendations for improving economic effectiveness of the realization of the Arctic projects on the basis of conceptual proposals for the development of entrepreneurship in industry. The paper presents the studies of the extractive industry role in the Russian economy and proves its raw material character. The analysis of production chains in industry on the basis of the conception of the added value global chains demonstrated a low added value formed by Russian companies. The study of changes in the structure of economy based on systemic, statistical and comparative analyses revealed no positive changes in the structure of economy over the period under consideration. This is a manifestation of ineffectiveness of the Russian industrial policy in general and within the Arctic region in particular. The authors identified the problems information and implementation of the state industrial policy in the Arctic region and in the development of national entrepreneurship, analyzed the shortcomings of the current state policy in the sphere of the Russian industry. On the basis of the conducted studies, the authors formulated conceptual approaches to change the state policy in the Arctic. The basic idea of the authors is to substantiate the focus of the state regulation on the development of entrepreneurship in industry in the process of the Russian Arctic exploration. At the same time another problem is solved–that of the development of the manufacturing industry in the southern regions of the northwestern part of Russia. The criterion of effectiveness in this case is the economic effectiveness.

Keywords: entrepreneurship in industry, global chains of the added value, government regulation, industrial policies, production chains in the arctic region, economic effectiveness

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Authors: Marina G. Galitskaya, Svetlana G. Makarova, Andrey P. Fisenko.

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Children on medication-induced immunosuppression are at high risk of developing severe course infectious diseases. Therefore, preventive vaccination is especially important for these children. However, due to the immunosuppressive effects of treatment for the underlying disease, the effectiveness of vaccination may decrease below the protective level. In a multidisciplinary children's medical center, post-vaccination immunity was studied in 79 children aged 4-17 years. The children were divided into 2 groups: Group 1 (38 children) with kidney pathology (Nephrotic Syndrome) and Group 2 (41 children) with inflammatory bowel diseases (Ulcerative Colitis, Crohn's Disease). Both groups of children were vaccinated according to the national vaccination calendar and received immunosuppressive therapy (prednisolone, methotrexate, cyclosporine, and other drugs) for at least 1 year. Using the enzyme-linked immunosorbent assay method, specific IgG antibodies to vaccine-preventable infections were determined: measles, rubella, mumps, diphtheria, pertussis, tetanus, and hepatitis B. The study showed the percentage of children with positive IgG values for vaccine-preventable infections. The highest percentage of children had protective antibody levels to measles (84.2% in children with nephrotic syndrome and 92.6% in those with inflammatory bowel disease) and rubella (71% and 80.4%, respectively). The lowest percentage of children with protective antibodies was for hepatitis B (5.2% and 29.2% respectively). Antibodies to mumps, diphtheria, pertussis, and tetanus were found not in all children (from 39,4% to 82,9%). The remaining percentage of children did not have detectable IgG antibodies to vaccine-preventable infections. Not all children, despite the previous vaccination, preserved antibodies to vaccine-controlled infections and remained unprotected by specific IgG antibodies. The issue of a booster vaccine dose should be considered in children without contraindications to vaccination. Children receiving long-term immunosuppressive therapy require an individual vaccination approach, including a specific definition of the performed vaccination.

Keywords: immunosuppressive therapy, inflammatory bowel diseases, nephrotic syndrome, post-vaccination immunity, specific antibodies, vaccine-preventable infections.

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Authors: R. Premasiri, W. A. H. A. Abeygunasekara, S. M. Hewavidana, T. Jananthan, R. M. S. Madawala, K. Vaheeshan

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Forecasting the potential for disastrous events such as landslides has become one of the major necessities in the current world. Most of all, the landslides occurred in Sri Lanka are found to be triggered mostly by intense rainfall events. The study area is the landslide near Gerandiella waterfall which is located by the 41st kilometer post on Nuwara Eliya-Gampala main road in Kotmale Division in Sri Lanka. The landslide endangers the entire Kotmale town beneath the slope. Geographic Information System (GIS) platform is very much useful when it comes to the need of emulating the real-world processes. The models are used in a wide array of applications ranging from simple evaluations to the levels of forecast future events. This project investigates the possibility of developing a dynamic model to map the spatial distribution of the slope stability. The model incorporates several theoretical models including the infinite slope model, Green Ampt infiltration model and Perched ground water flow model. A series of rainfall values can be fed to the model as the main input to simulate the dynamics of slope stability. Hydrological model developed using GIS is used to quantify the perched water table height, which is one of the most critical parameters affecting the slope stability. Infinite slope stability model is used to quantify the degree of slope stability in terms of factor of safety. DEM was built with the use of digitized contour data. Stratigraphy was modeled in Surfer using borehole data and resistivity images. Data available from rainfall gauges and piezometers were used in calibrating the model. During the calibration, the parameters were adjusted until a good fit between the simulated ground water levels and the piezometer readings was obtained. This model equipped with the predicted rainfall values can be used to forecast of the slope dynamics of the area of interest. Therefore it can be investigated the slope stability of rainfall induced landslides by adjusting temporal dimensions.

Keywords: factor of safety, geographic information system, hydrological model, slope stability

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Authors: Eleni Stefanidou, Nikolaos Katsenios, Ioanna Karamichali, Aspasia Efthimiadou, Panagiotis Madesis

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The excessive use of pesticides and fertilizers has significant environmental and human health-related negative effects. In the frame of the development of sustainable agriculture practices, especially in the context of extreme environmental changes (climate change), it is important to develop alternative practices to increase productivity and biotic and abiotic stress tolerance. Beneficial bacteria, such as symbiotic bacteria in legumes (rhizobia) and symbiotic or free-living Plant Growth Promoting Rhizobacteria (PGPR), which could act as "plant probiotics", can promote plant growth and significantly increase the resistance of crops under adverse environmental conditions. In this study, we explored the symbiotic relationships between Faba bean (Vicia faba L.) cultivars with different PGPR bacteria, aiming to identify the possible influence on yield and biotic-abiotic phytoprotection benefits. Transcriptomic analysis of root and whole plant samples was executed for two Vicia faba L. cultivars (Polikarpi and Solon) treated with selected PGPR bacteria (6 treatments: B. subtilis + Rhizobium-mixture, A. chroococcum + Rhizobium-mixture, B. subtilis, A. chroococcum and Rhizobium-mixture). Preliminary results indicate a significant yield (Seed weight and Total number of pods) increase in both varieties, ranging around 25%, in comparison to the control, especially for the Solon cultivar. The increase was observed for all treatments, with the B. subtilis + Rhizobium-mixture treatment being the highest performing. The correlation of the physiological and morphological data with the transcriptome analysis revealed molecular mechanisms and molecular targets underlying the observed yield increase, opening perspectives for the use of nitrogen-fixing bacteria as a natural, more ecological enhancer of legume crop productivity.

Keywords: plant probiotics, PGPR, legumes, sustainable agriculture

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Authors: Basant Kumar Singh, S. Subhachandhar, Vineet Ranjan Tripathi, Amit Kumar Singh, Uttam Singh, Santosh Kumar Lal

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Productivity of Blast Furnace is largely impacted by fuel efficiency and controlling heat loss is one of the enabling parameters for achieving lower fuel rate. 'I' Blast Furnace is the latest and largest Blast Furnace of Tata Steel Jamshedpur with working volume of 3230 m³ and with rated capacity of 3.055 million tons per annum. Optimizing heat losses in Belly and Bosh zone remained major challenge for blast furnace operators after its commissioning. 'I' Blast has installed Cast Iron & Copper Staves cooling members where copper staves are installed in Belly, Bosh & Lower Stack whereas cast iron staves are installed in upper stack area. Stave cooled Blast Furnaces are prone to higher heat losses in Belly and Bosh region with an increase in coal injection rate as Bosh gas volume increases. Under these conditions, managing gas flow pattern through proper burden distribution, casting techniques & by maintaining desired raw material qualities are of utmost importance for sustaining high injection rates. This study details, the burden distribution control by Ore & Coke ratio adjustment at wall and center of Blast Furnace as the coal injection rates increased from 140 kg/thm to 210 kg/thm. Control of blowing parameters, casting philosophy, specification for raw materials & devising operational practice for controlling heat losses is also elaborated with the model that is used to visualize heat loss pattern in different zones of Blast Furnace.

Keywords: blast furnace, staves, gas flow pattern, belly/bosh heat losses, ore/coke ratio, blowing parameters, casting, operation practice

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Authors: Erfan Rahimi, Hadi Bahari Far, Mojgan Shikhpour

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Background: Urinary tract infection is one of the most common nosocomial infections, especially among women. E. coli is one of the main causes of urinary tract infections and one of the most common antibiotics to fight this bacterium is ampicillin. As conventional antibiotics led to bacterial antibiotic resistance, modification of the pure drugs can address this issue. The aim of this study was to prepare nanofluids containing carbon nanotubes conjugated with ampicillin to improve drug performance and reduce antibiotic resistance. Methods: Multi-walled carbon nanotubes (MWCNTs) were activated with thionyl chloride by reflux system and nanofluids containing antibiotics were prepared by ultrasonic method. The properties of the prepared nano-drug were investigated by general element analysis, infrared spectroscopy, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. After the treatment of the desired strain with nanofluid, microbial studies were performed to evaluate the antibacterial effects and molecular studies were carried out to measure the expression of the resistance gene AcrAB. Result: We have shown that the antimicrobial effect of ampicillin-functionalized MWCNTs at low concentrations performed better than that of the conventional drug in both resistant and ATCC strains. Also, a decrease in antibiotic resistance of bacteria treated with ampicillin-functionalized MWCNTs compared to the pure drug was observed. Also, ampicillin-functionalized MWCNTs downregulated the expression of AcrAB in treated bacteria. Conclusion: Because carbon nanotubes are capable of destroying the bacterial wall, which provides antibiotic resistance features in bacteria, their usage in the form of nanofluids can make lower dosages (about three times less) than that of the pure drug more effective. Additionally, the expression of the bacterial resistance gene AcrAB decreased, thereby reducing antibiotic resistance and improving drug performance against bacteria.

Keywords: urinary tract infection, antibiotic resistance, carbon nanotube, nanofluid

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Authors: Venuka Kuruwita Arachchige Don, Mohamed Shaheen, Chris Goodier

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Aerated autoclaved concrete (AAC) is known for its lightweight, easy handling, high thermal insulation, and extremely porous structure. Investigation of pore behavior in AAC is crucial for characterizing the material, standardizing design and production techniques, enhancing the mechanical, durability, and thermal performance, studying the effectiveness of protective measures, and analyzing the effects of weather conditions. The significant details of pores are complicated to observe with acknowledged accuracy. The High-resolution Field Emission Scanning Electron Microscope (FESEM) image analysis is a promising technique for investigating the pore behavior and density of AAC, which is adopted in this study. Mercury intrusion porosimeter and gas pycnometer were employed to characterize porosity distribution and density parameters. The analysis considered three different densities of AAC blocks and three layers in the altitude direction within each block. A set of understandings was presented to extract and analyze the details of pore shape, pore size, pore connectivity, and pore percentages from FESEM images of AAC. Average pore behavior outcomes per unit area were presented. Comparison of porosity distribution and density parameters revealed significant variations. FESEM imaging offered unparalleled insights into porosity behavior, surpassing the capabilities of other techniques. The analysis conducted from a multi-staged approach provides porosity percentage occupied by various pore categories, total porosity, variation of pore distribution compared to AAC densities and layers, number of two-dimensional and three-dimensional pores, variation of apparent and matrix densities concerning pore behaviors, variation of pore behavior with respect to aluminum content, and relationship among shape, diameter, connectivity, and percentage in each pore classification.

Keywords: autoclaved aerated concrete, density, imaging technique, microstructure, porosity behavior

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Authors: H. Zouar, I. Kassous, F. Benzert

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The relentless pace of technology development in the last two decades has pervaded much of the recent educational discourse on a nation-wide scale. The rippling echoes of the buzz that account for the myriad of advantages the new technologies bring to the pedagogical activity has inevitably transcended from the western world to the Algerian educational contexts. Attempts have been made by Algerian practitioners to heed this digital advancement and push their instructional practices forward. However, due to the still largely existing first-order barriers as exemplified in the forms of deficient institutional infrastructure and unavailability of sufficient digital materials, the results of those attempts have polarised the views of Algerian academics regarding technology integration within higher education context. Hence, this study aims at measuring the possibility of integrating technology in our classrooms in a way that conforms to the philosophy of hybrid education. It also attempts to re-consider teachers’ understanding of technology integration in our context. Furthermore, the purpose of this research is also to reveal the level of teachers’ awareness regarding the distinction between technology integration and instrumental use. In view of the nature of these aims, a mixed-methods mode of investigation has been adopted to collect both qualitative and quantitative data from different perspectives. The data collection tools comprise of an observation as well as students’ and teachers’ questionnaires. The findings show that despite the fact that the examined context is not without its technological limitations, technology integration can be successfully incorporated contingent on teachers' level of knowledge and agency. Technology integration in Algerian universities does not proceed as the bedrock theory of it entails due to issues within teachers' general understanding of utilizing technology in class. It seems that technology is a means to an end, depending on the teachers who make use of it in order to deliver lessons (PowerPoint presentation) and issue commands (Facebook posting). Teachers' ability to clearly discern between integrating technology in their practices versus employing it as an instrument of instruction needs further consideration in order to establish a solid understanding of technology integration within higher education context.

Keywords: technology integration, hybrid education, teachers' understanding, teachers' awareness, instrumental use

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Authors: Dmitry Aron

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Major radiation accidents carry not only the potential risks of negative consequences for public health due to exposure but also because of large-scale emergency measures were taken by authorities to protect the population, which can lead to unreasonable social and economic damage. It is technically difficult, as a rule, to assess the possible costs and damages from decisions on evacuation or resettlement of residents in the shortest possible time, since it requires specially prepared information systems containing relevant information on demographic, economic parameters and incoming data on radiation conditions. Foreign observers also face the difficulties in assessing the consequences of an accident in a foreign territory, since they usually do not have official and detailed statistical data on the territory of foreign state beforehand. Also, they can suppose the application of unofficial data from open Internet sources is an unreliable and overly labor-consuming procedure. This paper describes an approach to prompt creation of relational database that contains detailed actual data on economics, demographics and radiation situation at the Fukushima Prefecture during the Fukushima Daiichi NPP accident, received by the author from open Internet sources. This database was developed and used to assess the number of evacuated population, radiation doses, expected financial losses and other parameters of the affected areas. The costs for the areas with temporarily evacuated and long-term resettled population were investigated, and the radiological and economic effectiveness of the measures taken to protect the population was estimated. Some of the results are presented in the article. The study showed that such a tool for analyzing the consequences of radiation accidents can be prepared in a short space of time for the entire territory of Japan, and it can serve for the modeling of social and economic consequences for hypothetical accidents for any nuclear power plant in its territory.

Keywords: Fukushima, radiation accident, emergency measures, database

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Authors: Saloni Pandya, Nikhil Sharma, Ajanta Sachan

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Expansive soils in the unsaturated state are part of vadose zone and encountered in several arid and semi-arid parts of the world. Influence of high temperature, low precipitation and alternate cycles of wetting and drying are responsible for the chemical weathering of rocks, which results in the formation of expansive soils. Shrinkage-swelling (expansive) soils cover a substantial portion of area in India. Damages caused by expansive soils to various geotechnical structures are alarming. Matric suction develops in unsaturated soil due to capillarity and surface tension phenomena. Matric suction influences the geometric arrangement of soil skeleton, which induces the volume change behaviour of expansive soil. In the present study, an attempt has been made to evaluate the role of matric suction in the mechanism behind swelling characteristics of expansive soil. Four different soils have been collected from different parts of India for the current research. Soil sample S1, S2, S3 and S4 were collected from Nagpur, Bharuch, Bharuch-Dahej highway and Ahmedabad respectively. DFSI (Differential Free Swell Index) of these soils samples; S1, S2, S3, and S4; were determined to be 134%, 104%, 70% and 30% respectively. X-ray diffraction analysis of samples exhibited that percentage of Montmorillonite mineral present in the soils reduced with the decrease in DFSI. A series of constant volume swell pressure tests and in-contact filter paper tests were performed to evaluate swelling pressure and matric suction of all four soils at 30% saturation and 1.46 g/cc dry density. Results indicated that soils possessing higher DFSI exhibited higher matric suction as compared to lower DFSI expansive soils. Significant influence of matric suction on swelling pressure of expansive soils was observed with varying DFSI values. Higher matric suction of soil might govern the water uptake in the interlayer spaces of Montmorillonite mineral present in expansive soil leading to crystalline swelling.

Keywords: differential free swell index, expansive soils, matric suction, swelling pressure

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Authors: Unsain Dianne, Roussel Audrey, Goude Gwenaëlle, Magniez Pierre, Storå Jan

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This paper aims to investigate the changes in husbandry practices and meat consumption during the transition from the Medieval Climate Anomaly to the Little Ice Age in the South of France. More precisely, we will investigate breeding strategies, animal size and health status, carcass exploitation strategies, and the impact of socioeconomic status on human-environment interactions. For that purpose, we will analyze faunal remains from ten sites equally distributed between the two periods. Those include consumers from different socio-economic backgrounds (peasants, city dwellers, soldiers, lords, and the Popes). The research will employ different methods used in zooarchaeology: comparative anatomy, biometry, pathologies analyses, traceology, and utility indices, as well as experimental archaeology, to reconstruct and understand the changes in animal breeding and consumption practices. Their analysis will allow the determination of modifications in the animal production chain, with the composition of the flocks (species, size), their management (age, sex, health status), culinary practices (strategies for the exploitation of carcasses, cooking, tastes) or the importance of trade (butchers, sales of processed animal products). The focus will also be on the social extraction of consumers. The aim will be to determine whether climate change has had a greater impact on the most modest groups (such as peasants), whether the consequences have been global and have also affected the highest levels of society, or whether the social and economic factors have been sufficient to balance out the climatic hazards, leading to no significant changes. This study will contribute to our understanding of the impact of climate change on breeding and consumption strategies in medieval society from a historical and social point of view. It combines various research methods to provide a comprehensive analysis of the changes in human-animal interactions during different climatic periods.

Keywords: archaeology, animal economy, cooking, husbandry practices, climate change, France

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Authors: Afsaneh Mohammadnejad, Marianne Nygaard, Jan Baumbach, Shuxia Li, Weilong Li, Jesper Lund, Jacob v. B. Hjelmborg, Lene Christensen, Qihua Tan

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Cognitive impairment in the elderly is a key issue affecting the quality of life. Despite a strong genetic background in cognition, only a limited number of single nucleotide polymorphisms (SNPs) have been found. These explain a small proportion of the genetic component of cognitive function, thus leaving a large proportion unaccounted for. We hypothesize that one reason for this missing heritability is the misspecified modeling in data analysis concerning phenotype distribution as well as the relationship between SNP dosage and the phenotype of interest. In an attempt to overcome these issues, we introduced a model-free method based on the generalized correlation coefficient (GCC) in a genome-wide association study (GWAS) of cognitive function in twin samples and compared its performance with two popular linear regression models. The GCC-based GWAS identified two genome-wide significant (P-value < 5e-8) SNPs; rs2904650 near ZDHHC2 on chromosome 8 and rs111256489 near CD6 on chromosome 11. The kinship model also detected two genome-wide significant SNPs, rs112169253 on chromosome 4 and rs17417920 on chromosome 7, whereas no genome-wide significant SNPs were found by the linear mixed model (LME). Compared to the linear models, more meaningful biological pathways like GABA receptor activation, ion channel transport, neuroactive ligand-receptor interaction, and the renin-angiotensin system were found to be enriched by SNPs from GCC. The GCC model outperformed the linear regression models by identifying more genome-wide significant genetic variants and more meaningful biological pathways related to cognitive function. Moreover, GCC-based GWAS was robust in handling genetically related twin samples, which is an important feature in handling genetic confounding in association studies.

Keywords: cognition, generalized correlation coefficient, GWAS, twins

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Authors: Zahid Ullah, Atlas Khan

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This research endeavors to explore the regularity properties associated with a specific class of equations, namely extremely degenerate elliptic equations. These equations hold significance in understanding complex physical systems like porous media flow, with applications spanning various branches of mathematics. The focus is on unraveling and analyzing regularity results to gain insights into the smoothness of solutions for these highly degenerate equations. Elliptic equations, fundamental in expressing and understanding diverse physical phenomena through partial differential equations (PDEs), are particularly adept at modeling steady-state and equilibrium behaviors. However, within the realm of elliptic equations, the subset of extremely degenerate cases presents a level of complexity that challenges traditional analytical methods, necessitating a deeper exploration of mathematical theory. While elliptic equations are celebrated for their versatility in capturing smooth and continuous behaviors across different disciplines, the introduction of degeneracy adds a layer of intricacy. Extremely degenerate elliptic equations are characterized by coefficients approaching singular behavior, posing non-trivial challenges in establishing classical solutions. Still, the exploration of extremely degenerate cases remains uncharted territory, requiring a profound understanding of mathematical structures and their implications. The motivation behind this research lies in addressing gaps in the current understanding of regularity properties within solutions to extremely degenerate elliptic equations. The study of extreme degeneracy is prompted by its prevalence in real-world applications, where physical phenomena often exhibit characteristics defying conventional mathematical modeling. Whether examining porous media flow or highly anisotropic materials, comprehending the regularity of solutions becomes crucial. Through this research, the aim is to contribute not only to the theoretical foundations of mathematics but also to the practical applicability of mathematical models in diverse scientific fields.

Keywords: elliptic equations, extremely degenerate, regularity results, partial differential equations, mathematical modeling, porous media flow

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Authors: Abbas Ali Husseini, Ali Mohammad Yazdani, Fatemeh Ghadiri, Alper Şişman

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We developed a microchip device that uses surface acoustic waves for rapid lysis of low level of cell samples. The device incorporates sharp-edge glass microparticles for improved performance. We optimized the lysis conditions for high efficiency and evaluated the device's feasibility for point-of-care applications. The microchip contains a 13-finger pair interdigital transducer with a 30-degree focused angle. It generates high-intensity acoustic beams that converge 6 mm away. The microchip operates at a frequency of 16 MHz, exciting Rayleigh waves with a 250 µm wavelength on the LiNbO3 substrate. Cell lysis occurs when Candida albicans cells and glass particles are placed within the focal area. The high-intensity surface acoustic waves induce centrifugal forces on the cells and glass particles, resulting in cell lysis through lateral forces from the sharp-edge glass particles. We conducted 42 pilot cell lysis experiments to optimize the surface acoustic wave-induced streaming. We varied electrical power, droplet volume, glass particle size, concentration, and lysis time. A regression machine-learning model determined the impact of each parameter on lysis efficiency. Based on these findings, we predicted optimal conditions: electrical signal of 2.5 W, sample volume of 20 µl, glass particle size below 10 µm, concentration of 0.2 µg, and a 5-minute lysis period. Downstream analysis successfully amplified a DNA target fragment directly from the lysate. The study presents an efficient microchip-based cell lysis method employing acoustic streaming and microparticle collisions within microdroplets. Integration of a surface acoustic wave-based lysis chip with an isothermal amplification method enables swift point-of-care applications.

Keywords: cell lysis, surface acoustic wave, micro-glass particle, droplet

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Authors: George Madalin Danila, Mihaiella Cretu, Cristian Puscasu

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The recycling of used antifreeze/coolant is a widely discussed and intricate issue. Complying with government regulations for the proper disposal of hazardous waste poses a significant challenge for today's automotive and industrial industries. In recent years, global focus has shifted toward Earth's fragile ecology, emphasizing the need to restore and preserve the natural environment. The business and industrial sectors have undergone substantial changes to adapt and offer products tailored to these evolving markets. The global antifreeze market size was evaluated at US 5.4 billion in 2020 to reach USD 5,9 billion by 2025 due to the increased number of vehicles worldwide, but also to the growth of HVAC systems. This study presents the evaluation of an ion exchange resin-based installation designed for the recycling of engine coolants, specifically ethylene glycol (EG) and propylene glycol (PG). The recycling process aims to restore the coolant to meet the stringent ASTM standards for both new and recycled coolants. A combination of physical-chemical methods, gas chromatography-mass spectrometry (GC-MS), and inductively coupled plasma mass spectrometry (ICP-MS) was employed to analyze and validate the purity and performance of the recycled product. The experimental setup included performance tests, namely corrosion to glassware and the tendency to foaming of coolant, to assess the efficacy of the recycled coolants in comparison to new coolant standards. The results demonstrate that the recycled EG coolants exhibit comparable quality to new coolants, with all critical parameters falling within the acceptable ASTM limits. This indicates that the ion exchange resin method is a viable and efficient solution for the recycling of engine coolants, offering an environmentally friendly alternative to the disposal of used coolants while ensuring compliance with industry standards.

Keywords: engine coolant, glycols, recycling, ion exchange resin, circular economy

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Authors: Haoxiang Desmond Lim, Jie Wu, Tze How Daniel New, Shengxian Shi

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This paper outlines the development of a novel experimental technique in quantifying supersonic jet flows, in an attempt to avoid seeding particle problems frequently associated with particle-image velocimetry (PIV) techniques at high Mach numbers. Based on optical flow algorithms, the idea behind the technique involves using high speed cameras to capture Schlieren images of the supersonic jet shear layers, before they are subjected to an adapted optical flow algorithm based on the Horn-Schnuck method to determine the associated flow fields. The proposed method is capable of offering full-field unsteady flow information with potentially higher accuracy and resolution than existing point-measurements or PIV techniques. Preliminary study via numerical simulations of a circular de Laval jet nozzle successfully reveals flow and shock structures typically associated with supersonic jet flows, which serve as useful data for subsequent validation of the optical flow based experimental results. For experimental technique, a Z-type Schlieren setup is proposed with supersonic jet operated in cold mode, stagnation pressure of 8.2 bar and exit velocity of Mach 1.5. High-speed single-frame or double-frame cameras are used to capture successive Schlieren images. As implementation of optical flow technique to supersonic flows remains rare, the current focus revolves around methodology validation through synthetic images. The results of validation test offers valuable insight into how the optical flow algorithm can be further improved to improve robustness and accuracy. Details of the methodology employed and challenges faced will be further elaborated in the final conference paper should the abstract be accepted. Despite these challenges however, this novel supersonic flow measurement technique may potentially offer a simpler way to identify and quantify the fine spatial structures within the shock shear layer.

Keywords: Schlieren, optical flow, supersonic jets, shock shear layer

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Authors: Anders Troedsson

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For us humans, risks are intimately linked to human vulnerabilities - where there is vulnerability, there is potentially insecurity, and risk. Reducing vulnerability through compensatory measures means increasing security and decreasing risk. The paper suggests that a meaningful way to approach the study of risks (including threats, assaults, crisis etc.), is to understand the vulnerabilities these external phenomena evoke in humans. As is argued, the basis of risk evaluation, as well as responses, is the more or less subjective perception by the individual person, or a group of persons, exposed to the external event or phenomena in question. This will be determined primarily by the vulnerability or vulnerabilities that the external factor are perceived to evoke. In this way, risk perception is primarily an inward dynamic, rather than an outward one. Therefore, a route towards an understanding of the perception of risks, is a closer scrutiny of the vulnerabilities which they can evoke, thereby approaching an understanding of what in the paper is called the essence of risk (including threat, assault etc.), or that which a certain perceived risk means to an individual or group of individuals. As a necessary basis for gauging the wide spectrum of potential risks and their meaning, the paper proposes a model of human vulnerabilities, drawing from i.a. a long tradition of needs theory. In order to account for the subjectivity factor, which mediates between the innate vulnerabilities on the one hand, and the event or phenomenon out there on the other hand, an ensuing ontological discussion about the timespace characteristics of risk/threat/assault as perceived by humans leads to the positing of two dimensions. These two dimensions are applied on the vulnerabilities, resulting in a modelling effort featuring four realms of vulnerabilities which are related to each other and together represent a dynamic whole. In approaching the problem of risk perception, the paper thus defines the relevant realms of vulnerabilities, depicting them as a dynamic whole. With reference to a substantial body of literature and a growing international policy trend since the 1990s, this model is put in the language of human security - a concept relevant not only for international security studies and policy, but also for other academic disciplines and spheres of human endeavor.

Keywords: human security, timespace, vulnerabilities, risk perception

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Authors: Yusuf E. Mustapha, Inioluwa A Akindoyeni, Oluwatoyin G. Ezekiel, Ifeoluwa O. Awogbindin, Ebenezer O. Farombi

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Background: Parkinson's disease (PD) is the most prevalent motor disorder. Available therapies are palliative with no effect on disease progression. Kolaviron (KV), a natural anti-inflammatory and antioxidant agent, has been reported to possess neuroprotective effects in Parkinsonian flies and rats. Objective: The present study investigates the neuroprotective effect of KV, focusing on the DJ1/Nrf2 signaling pathway. Methodology: All-trans retinoic acid (ATRA, 10 mg/kg, i.p.) was used to inhibit Nrf2. Murine model of PD was established with four doses of MPTP (20 mg/kg i.p.) at 2 hours interval. MPTP mice were pre-treated with either KV (200 mg/kg/day p.o), ATRA, or both conditions for seven days before PD induction. Motor behaviour was evaluated, and markers of oxidative stress/damage and its regulators were assessed with immunofluorescence and ELISA techniques. Results: MPTP-treated mice covered less distance with reduced numbers of anticlockwise rotations, heightened freezing, and prolonged immobility when compared to control. However, KV significantly attenuated these deficits. Pretreatment of MPTP mice with KV upregulated Nrf2 expression beyond MPTP level with a remarkable reduction in Keap1 expression and marked elevation of DJ-1 level, whereas co-administration with ATRA abrogated these effects. KV treatment restored MPTP-mediated depletion of endogenous antioxidant, striatal oxidative stress, oxidative damage, and inhibition of acetylcholinesterase activity. However, ATRA treatment potentiated acetylcholinesterase inhibition and attenuated the protective effect of KV on the level of nitric oxide and activities of catalase and superoxide dismutase. Conclusion: Kolaviron protects Parkinsonian mice by stabilizing and activating the Nrf2 signaling pathway. Thus, kolaviron can be explored as a pharmacological lead in PD management.

Keywords: Garcinia kola, Kolaviron, Parkinson Disease, Nrf2, behavioral incompetence, neurodegeneration

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Authors: Neuma Chaveiro, Juliana Guimarães Faria

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Introduction: The thematic that guides this study is teacher training for the teaching of sign language in a perspective of bilingual education – specifically aimed at Brazilian public schools that offer inclusive education, and that have, among its students, deaf children who use Brazilian Sign Language as a means of communication and expression. In the Teacher Training Course for Letters/Libras at the Universidade Federal de Goiás/UFG, we developed a bilingual education project for the deaf, linked to PIBID (Institutional Scholarship for Teaching Initiation Program), funded by the Brazilian Federal Government through CAPES (Coordination for the Improvement of Higher Education Personnel). Goals: to provide the education of higher education teachers to work in public schools in basic education and to insert students from the UFG’s Letters/Libras course in the school’s daily life, giving them the opportunity for the creation and participation in methodological experiences and of teaching practices in order to overcome the problems identified in the teaching-learning process of deaf students, in a bilingual perspective, associating Libras (Brazilian Sign Language) and Portuguese. Methodology: qualitative approach and research-action, prioritizing action – reflection – action of the people involved. The Letters-Libras PIBID of the College of Letters/UFG, in this qualitative context, is guided by the assumptions of investigation-action to contribute to the education of the Libras teacher. Results: production of studies and researches in the area of education, professionalization and teaching practice for the degree holder in Letters: Libras; b) studies, research and training in bilingual education; c) clarification and discussion of the myths that permeate the reality of users of sign languages; d) involving students in the development of didactic materials for bilingual education. Conclusion: the PIBID Project Letters/Libras allows, both to the basic education school and to the teachers in training for the teaching of Libras, an integrated and collective work partnership, with discussions and changes in relation to bilingual education for the deaf and the teaching of Libras.

Keywords: deaf, sign language, teacher training, educacion

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Authors: Tamseela Habib, Muhammad Amjad, Muhammad Edokali, Masome Moeni, Olivia Pickup, Ali Hassanpour

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Nanofluid-assisted steam generation is rapidly attracting attention amongst the scientific community since it can be applied in a wide range of industrial processes. Because of its high absorption rate of solar energy, nanoparticle-based solar steam generation could be a major contributor to many applications, including water desalination, sterilization and power generation. Lithium bromide-based iron oxide nanofluids have been previously studied in steam generation, which showed promising results. However, the efficiency of the system could be improved if a more heat-conductive nanofluid system could be utilised. In the current paper, we report on an experimental investigation of the photothermal conversion properties of functionalised Copper oxide (CuO) nanoparticles used in Lithium Bromide salt solutions. CuO binary nanofluid was prepared by chemical functionalization with polyethyleneimine (PEI). Long-term stability evaluation of prepared binary nanofluid was done by a high-speed centrifuge analyser which showed a 0.06 Instability index suggesting low agglomeration and sedimentation tendencies. This stability is also supported by the measurements from dynamic light scattering (DLS), transmission electron microscope (TEM), and ultraviolet-visible (UV-Vis) spectrophotometer. The fluid rheology is also characterised, which suggests the system exhibits a Newtonian fluid behavior. The photothermal conversion efficiency of different concentrations of CuO was experimentally investigated under a solar simulator. Experimental results reveal that the binary nanofluid in this study can remarkably increase the solar energy trapping efficiency and evaporation rate as compared to conventional fluids due to localized solar energy harvesting by the surface of the nanofluid. It was found that 0.1wt% CuO NP is the optimum nanofluid concentration for enhanced sensible and latent heat efficiencies.

Keywords: nanofluids, vapor absorption refrigeration system, steam generation, high salinity

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Authors: Asma Abdullah, Awais Khan, Reem Al-Ghumlasi, Pritam Kumari, Yasir Nawaz

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Introduction: This study verified the potential applications of two Oblique Wing configurations that were initiated by the Germans Aerodynamicists during the WWII. Due to the end of the war, this project was not completed and in this research is targeting the revival of German Oblique biplane configuration. The research draws upon the use of two Oblique wings mounted on the top and bottom of the fuselage through a single pivot. The wings are capable of sweeping at different angles ranging from 0° at takeoff to 60° at cruising Altitude. The top wing, right half, behaves like a forward swept wing and the left half, behaves like a backward swept wing. Vice Versa applies to the lower wing. This opposite deflection of the top and lower wing cancel out the rotary moment created by each wing and the aircraft remains stable. Problem to better understand or solve: The purpose of this research is to investigate the potential of achieving improved aerodynamic performance and efficiency of flight at a wide range of sweep angles. This will help examine the most accurate value for the sweep angle at which the aircraft will possess both stability and better aerodynamics. Explaining the methods used: The Aircraft configuration is designed using Solidworks after which a series of Aerodynamic prediction are conducted, both in the subsonic and the supersonic flow regime. Computations are carried on Ansys Fluent. The results are then compared to theoretical and flight data of different Supersonic fighter aircraft of the same category (AD-1) and with the Wind tunnel testing model at subsonic speed. Results: At zero sweep angle, the aircraft has an excellent lift coefficient value with almost double that found for fighter jets. In acquiring of supersonic speed the sweep angle is increased to maximum 60 degrees depending on the mission profile. General findings: Oblique biplane can be the future fighter jet aircraft because of its high value performance in terms of aerodynamics, cost, structural design and weight.

Keywords: biplane, oblique wing, sweep angle, supercritical airfoil

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Authors: Hela Ghali, Oumayma Ben Amor, Salwa Khefacha, Mohamed Ben Rejeb, Sirine Frigui, Meriam Tourki Dhidah, Lamine Dhidah, Houyem Said Laatiri

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Background: Blood exposure accidents are the most common problem in hospitals that threaten healthcare professionals with a high risk of infectious complications which weighs heavily on health systems worldwide. Paramedics are the highest risk group due to the nature of their daily activities. We aimed to determine knowledge and attitudes about the management of blood-exposure accidents among nurses and technicians in two pediatric departments. Materials/Methods: This is a cross-sectional descriptive study conducted on March 2017, carried out with the care staff of the pediatric ward of the Farhat Hached Teaching Hospital of Sousse and pediatric surgery of the Fattouma Bourguiba University Hospital in Monastir, using a pre- tested and self-administered questionnaire. Data entry and analysis were performed using Excel software. Results: The response rate was 85.1%. A female predominance (82.5%) was reported among respondents with a sex ratio of 0.21. 80% of the participants were under 35 years old. Seniority of less than 10 years was found in 77.5% of respondents. Only 22.5% knew the definition of a blood- exposure accident. 100% and 95% of participants reported the relative risk, respectively, to hepatitis and AIDS viruses. However, only 15% recognized the severity factors of a blood-exposure accident. Hygiene compliance was the most important dimension for almost the entire population for the prevention. On the other hand, only 12.5% knew the meaning of 'standard precautions' and ¼ considered them necessary for at-risk patients only. 40% reported being exposed at least once, among them, 87.5% used betadine, and 77.5% said that anti-infectious chemoprophylaxis is necessary regardless of the patient's serological status. However, 52.5% did not know the official reporting circuit of management of blood-exposure accident in their institutions. Conclusion: For better management of risks in hospitals and an improvement of the safety of the care, a reinforcement of the sensibilization of the caregivers with regard to the risks of blood exposure accident is necessary, while developing their knowledge to act in security.

Keywords: attitudes, blood-exposure accident, knowledge, pediatric department

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Authors: Zeynep Yazicioglu

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Project development is a complex process where many stakeholders work together. Employers and main contractors are the base stakeholders, whereas designers, engineers, sub-contractors, suppliers, supervisors, and consultants are other stakeholders. A combination of the complexity of the building process with a large number of stakeholders often leads to time and cost overruns and irregular resource utilization. Failure to comply with the work schedule and inefficient use of resources in the construction processes indicate that it is necessary to accelerate production and increase productivity. The development of computer software called Building Information Modeling, abbreviated as BIM, is a major technological breakthrough in this area. The use of BIM enables architectural, structural, mechanical, and electrical projects to be drawn in coordination. BIM is a tool that should be considered by every stakeholder with the opportunities it offers, such as minimizing construction errors, reducing construction time, forecasting, and determination of the final construction cost. It is a process spreading over the years, enabling all stakeholders associated with the project and construction to use it. The main goal of this paper is to explore the problems associated with the adoption of BIM in multi-stakeholder projects. The paper is a conceptual study, summarizing the author’s practical experience with design offices and construction firms working with BIM. In the transition period to BIM, three of the challenges will be examined in this paper: 1. The compatibility of supplier companies with BIM, 2. The need for two-dimensional drawings, 3. Contractual issues related to BIM. The paper reviews the literature on BIM usage and reviews the challenges in the transition stage to BIM. Even on an international scale, the supplier that can work in harmony with BIM is not very common, which means that BIM's transition is continuing. In parallel, employers, local approval authorities, and material suppliers still need a 2-D drawing. In the BIM environment, different stakeholders can work on the same project simultaneously, giving rise to design ownership issues. Practical applications and problems encountered are also discussed, providing a number of suggestions for the future.

Keywords: BIM opportunities, collaboration, contract issues about BIM, stakeholders of project

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Authors: Jéssica Ferreira Rodrigues, Júlio Silvio De Sousa Bueno Filho, Vanessa Rios De Souza, Ana Carla Marques Pinheiro

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This study aimed to evaluate the implications of the block size and testing order on efficiency and precision of preference estimation for Dulce de leche samples. Efficiency was defined as the inverse of the average variance of pairwise comparisons among treatments. Precision was defined as the inverse of the variance of treatment means (or effects) estimates. The experiment was originally designed to test 16 treatments as a series of 8 Sudoku 16x16 designs being 4 randomized independently and 4 others in the reverse order, to yield balance in testing order. Linear mixed models were assigned to the whole experiment with 112 testers and all their grades, as well as their partially balanced subgroups, namely: a) experiment with the four initial EU; b) experiment with EU 5 to 8; c) experiment with EU 9 to 12; and b) experiment with EU 13 to 16. To record responses we used a nine-point hedonic scale, it was assumed a mixed linear model analysis with random tester and treatments effects and with fixed test order effect. Analysis of a cumulative random effects probit link model was very similar, with essentially no different conclusions and for simplicity, we present the results using Gaussian assumption. R-CRAN library lme4 and its function lmer (Fit Linear Mixed-Effects Models) was used for the mixed models and libraries Bayesthresh (default Gaussian threshold function) and ordinal with the function clmm (Cumulative Link Mixed Model) was used to check Bayesian analysis of threshold models and cumulative link probit models. It was noted that the number of samples tested in the same session can influence the acceptance level, underestimating the acceptance. However, proving a large number of samples can help to improve the samples discrimination.

Keywords: acceptance, block size, mixed linear model, testing order, testing order

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Authors: Shama Ranjan Barua, Tofazzal M. Rakib, Mohammad Alamgir Hossain, Tania Ferdushy, Sharmin Chowdhury

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Rotavirus is one of the main etiologies of neonatal diarrhea in bovine calves that causes significant economic loss in Bangladesh. The present study was carried out to investigate the pathology of neonatal enteritis in calves due to bovine rotavirus infection in south-eastern part of Bangladesh. Rotavirus was identified by using ELISA, RT-PCR (Reverse Transcription Polymerase Chain Reaction), real-time RT-PCR. We examined 12 dead calves with history of diarrhea during necropsy. Among 12 dead calves, in gross examination, 6 were found with pathological changes in intestine, 5 calves had congestion of small intestine and rest one had no distinct pathological changes. Intestinal contents and/or faecal samples of all dead calves were collected and examined to confirm the presence of bovine rotavirus A using Enzyme linked immunosorbant assay (ELISA), RT-PCR and real-time RT-PCR. Out 12 samples, 5 (42%) samples revealed presence of bovine rotavirus A in three diagnostic tests. The histopathological changes were found almost exclusively limited in the small intestine. The lesions of rotaviral enteritis ranged from slight to moderate shortening (atrophy) of villi in the jejunum and ileum with necrotic crypts. The villi were blunt and covered by immature epithelial cells. Infected cells, stained with Haematoxylin and Eosin staining method, showed characteristic syncytia and eosinophilc intracytoplasmic inclusion body. The presence of intracytoplasmic inclusion bodies in enterocytes is the indication of viral etiology. The presence of rotavirus in the affected tissues and/or lesions was confirmed by three different immunological and molecular tests. The findings of histopathological changes will be helpful in future diagnosis of rotaviral infection in dead calves.

Keywords: calves, diarrhea, pathology, rotavirus

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Authors: Kana Matsuyanagi

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Anorexia Nervosa (AN) is a psychiatric disorder characterized by a relentless pursuit of thinness and strict restriction of food. The current therapeutic approaches for AN predominantly revolve around outpatient psychotherapies, which create significant financial barriers for the majority of affected patients, hindering their access to treatment. Nonetheless, AN exhibit one of the highest mortality and relapse rates among psychological disorders, underscoring the urgent need to provide patients with an affordable self-treatment tool, enabling those unable to access conventional medical intervention to address their condition autonomously. To this end, a neurofeedback software, termed RelaxNeuron, was developed with the objective of providing an economical and portable means to aid individuals in self-managing AN. Electroencephalography (EEG) was chosen as the preferred modality for RelaxNeuron, as it aligns with the study's goal of supplying a cost-effective and convenient solution for addressing AN. The primary aim of the software is to ameliorate the negative emotional responses towards food stimuli and the accompanying aberrant eye-tracking patterns observed in AN patient, ultimately alleviating the profound fear towards food an elemental symptom and, conceivably, the fundamental etiology of AN. The core functionality of RelaxNeuron hinges on the acquisition and analysis of EEG signals, alongside an electrocardiogram (ECG) signal, to infer the user's emotional state while viewing dynamic food-related imagery on the screen. Moreover, the software quantifies the user's performance in accurately tracking the moving food image. Subsequently, these two parameters undergo further processing in the subsequent algorithm, informing the delivery of either negative or positive feedback to the user. Preliminary test results have exhibited promising outcomes, suggesting the potential advantages of employing RelaxNeuron in the treatment of AN, as evidenced by its capacity to enhance emotional regulation and attentional processing through repetitive and persistent therapeutic interventions.

Keywords: Anorexia Nervosa, fear conditioning, neurofeedback, BCI

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Authors: Chetna Khandelwal

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This research aims to study the contentions that Farm Animal Sanctuaries pose to human-animal relationships in modernity, which have developed as a result of globalisation of the meat industry and advancements in technology. The sociological history of human-animal relationships in farming is contextualised in order to set a foundation for the follow-up examination of challenges to existing human-(farm)animal relationships by Farm Animal Sanctuaries. The methodology was influenced by relativism, and the method involved three semi-structured small-group interviews, conducted at locations of sanctuaries. The sample was chosen through purposive sampling and varied by location and size of the sanctuary. Data collected were transcribed and qualitatively coded to generate themes. Findings revealed that sanctuary contentions to established human-animal relationships by factory farming could be divided into 4 broad categories – Revealing horrors of factory farming (involving uncovering power relations in agribusiness); transforming relationships with animals (including letting them emotionally heal in accordance with their individual personalities and treating them as partial-pets); educating the public regarding welfare conditions in factory farms as well as animal sentience through practical experience or positive imagery of farm animals, and addressing retaliation made by agribusiness in the form of technologies or discursive strategies. Hence, this research concludes that The human-animal relationship in current times has been characterised by – (ideological and physical) distance from farm animals, commodification due to increased chasing of profits over welfare and exploitation using technological advancements, creating unequal power dynamics that rid animals of any agency. Challenges to this relationship can be influenced by local populations around the sanctuary but not so dependent upon the size of it. This research can benefit from further academic exploration into farm animal sanctuaries and their role in feminist animal rights activism to enrich the ongoing fight against intensive farming.

Keywords: animal rights, factory farming, farm animal sanctuaries, human-animal relationships

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Authors: Vasilis Andriopoulos, Maria D. Gkioni, Elena Koutra, Savvas G. Mastropetros, Fotini N. Lamari, Sofia Hatziantoniou, Michalis Kornaros

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In the present study, the antioxidant activity of aqueous and methanolic extracts of Chlorella minutissima, Dunaliella salina, Isochrysis galbana, Nannochloropsis oculata and Tisohrysis lutea, as well as the proximate composition and fatty acid profile were evaluated, with the aim to select species suitable for co-production of antioxidants and aquaculture feed. Batch cultivation was performed at 25oC in a modified f/2 medium under continuous illumination and aeration with ambient air. Biomass was collected via centrifugation and extracted first with H2O and subsequently with methanol at two growth phases (early and late stationary). Total phenolic content and antioxidant and reducing activity of the extracts were evaluated. The highest phenolic content was found in the methanolic extract of C. minutissima at the early stationary phase (9.04±0.68 mg Gallic Acid Equivalent g-1 dry weight), and the aqueous extract of D. salina at the late stationary phase (8.78±1.49 mg Gallic Acid Equivalent g-1 Dry weight). Antioxidant activity, measured as 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, and Ferric reducing antioxidant power assay of methanolic extracts were comparable to the literature and correlated to Total phenolic content and Chlorophyll content of the biomass. No such correlation was found in the aqueous extracts. N. oculata and T. lutea were high in protein (39.88±1.72% Dry weight and 43.30±1.33% Dry weight, respectively) and carotenoids (0.64±0.13% and 0.92±0.02%, respectively). Additionally, they presented high eicosapentaenoic acid and docosahexaenoic acid levels (33.74±9.98 mg eicosapentaenoic acid g-1 DW and 31.31±2.92 mg docosahexaenoic acid g-1 dry weight, respectively). N. oculata and T. lutea are promising candidates for the co-production of antioxidants and aquaculture feed, while C. minutissima and D. salina showed promise due to their higher antioxidant content.

Keywords: aquaculture fee, antioxidant activity, fatty acids, microalgae, total phenolic content

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Authors: Xiaowei Zhang, Min Xu, Saeid Habibi, Fengjun Yan, Ryan Ahmed

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Recently, Electric Vehicles (EVs) have received extensive consideration since they offer a more sustainable and greener transportation alternative compared to fossil-fuel propelled vehicles. Lithium-Ion (Li-ion) batteries are increasingly being deployed in EVs because of their high energy density, high cell-level voltage, and low rate of self-discharge. Since Li-ion batteries represent the most expensive component in the EV powertrain, accurate monitoring and control strategies must be executed to ensure their prolonged lifespan. The Battery Management System (BMS) has to accurately estimate parameters such as the battery State-of-Charge (SOC), State-of-Health (SOH), and Remaining Useful Life (RUL). In order for the BMS to estimate these parameters, an accurate and control-oriented battery model has to work collaboratively with a robust state and parameter estimation strategy. Since battery physical parameters, such as the internal resistance and diffusion coefficient change depending on the battery state-of-life (SOL), the BMS has to be adaptive to accommodate for this change. In this paper, an extensive battery aging study has been conducted over 12-months period on 5.4 Ah, 3.7 V Lithium polymer cells. Instead of using fixed charging/discharging aging cycles at fixed C-rate, a set of real-world driving scenarios have been used to age the cells. The test has been interrupted every 5% capacity degradation by a set of reference performance tests to assess the battery degradation and track model parameters. As battery ages, the combined model parameters are optimized and tracked in an offline mode over the entire batteries lifespan. Based on the optimized model, a state and parameter estimation strategy based on the Extended Kalman Filter (EKF) and the relatively new Smooth Variable Structure Filter (SVSF) have been applied to estimate the SOC at various states of life.

Keywords: lithium-ion batteries, genetic algorithm optimization, battery aging test, parameter identification

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