540 research outputs found

    Economical adjunction of square roots to groups

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    How large must an overgroup of a given group be in order to contain a square root of any element of the initial group? We give an almost exact answer to this question (the obtained estimate is at most twice worse than the best possible) and state several related open questions.Comment: 5 pages. A Russian version of this paper is at http://mech.math.msu.su/department/algebra/staff/klyachko/papers.htm V2: minor correction

    Cultural intermediation: cultural offer and cultural practices

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    With the desire to promote excellence in higher education in Portugal and develop the Alto Minho region, the positive association that exists between art education in improving individual skills, and increasing cultural participation and academic results and Viana do Castelo School of Higher Education (VCHSE) was establihed. The determination of importance that the Polytechnic Institute of Viana do Castelo [IPVC] has in the plan to comply with the cultural strategy of Europe 2020 initiatives was the starting point for a group of teachers and researchers of to consider the weight of school capital and cultural consumption, in relationship to the lack of correlation between increased cultural offerings and increased cultural consumption. Through these investigations, VCHSE began to inquire into the relevance of designing and implementing a program of cultural intermediation that could develop students? cultural practices through art education, improving the skills of professionals qualified by the Institute. The aim of this paper is to briefly present the VCHSE strategy to diagnosis the cultural practices of IPVC students in order to design a pilot program, Cultural Intermediation in Higher Education in Viana do Castelo, which will be implemented at the VCHSE.B416-43A6-419A | Adalgisa Castro Maia Pontesinfo:eu-repo/semantics/publishedVersio

    Second-hand smoke exposure and health-related quality of life in never smokers: The Hong Kong Jockey Club Family Project

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    Conference Theme: Tobacco and Non-Communicable DiseasesOral Presentation - 08. Smoke-Free Environments: no. OP-243-20BACKGROUND: Despite the mounted evidence on the adverse health effects of secondhand smoke (SHS), the evidence is limited on the relation between SHS exposure and Health Related Quality of Life (HRQoL). METHODS: SHS exposure was self-reported by a probability sample of adult never smokers aged 18 or above from the 2010, 2012 and 2013 waves of The Hong Kong Family and Health Information Trends Survey (FHinTs) of FAMILY Project (www.family.org.hk). HRQoL was measured using the validated Cantonese version of Short Form 12 …published_or_final_versio

    Carbonyl group generation on single-wall carbon nanotubes with nitric acid: A theoretical description

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    AbstractThe initial steps of single-wall carbon nanotube (SWNT) oxidation in nitric acid were studied using a (6,6) supercell with a mono-vacancy defect and employing spin-polarised density functional theory. According to our results, the geometric changes that occur during the process are significantly localised around the vacancy. The carbonyl group generation does not change the metallic nature of the nanosystem. Vibrational thermal corrections calculated using full and partial Hessian vibrational analysis indicated a small contribution to the reaction energy. An overall favourable oxidation pathway is proposed and includes an initial NO2+ exothermic electrophilic attack followed by an endothermic oxaziridine formation

    Sedentary behaviour impairs skeletal muscle repair modulating the inflammatory response

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    This study investigated whether sedentary behaviour modulates skeletal-muscle repair and tissue inflammatory response after cardiotoxin (CTX)-induced injury. Singly caged rats spent 8 weeks either as a sedentary group (SED, n = 15) or as a control group (EX, n = 15)?caged with running wheels for voluntary running. All rats had each tibial anterior muscle infused either with CTX (CTX; right muscle) or saline solution (Sham; left muscle) and were sacrificed (n = 5 per group) on the 1st, 7th, and 15th day post-injection (dpi). Histological and immunohistochemical analyses were used to calculate myotube percentage and fibrosis accretion, and quantify the number of neutrophils and M1 and M2 macrophage subtypes. The SED group showed an increased number of both neutrophils and M1 macrophages (7th and 15th dpi) compared to the EX group (p < 0.01). The EX group showed an increased number of M2 macrophages on the 1st dpi. On the 7th dpi, the SED group showed a lower myotube percentage compared to the EX group (p < 0.01) and on the 15th dpi showed only 54% of normal undamaged fibres compared to 90% from the EX group (p < 0.01). The SED group showed increased fibrosis on both the 7th and 15th dpi. Our results show that sedentary behaviour affects the inflammatory response, enhancing and prolonging the Th1 phase, and delays and impairs the SMR process.DB19-D819-F720 | Carlos Eduardo da Silva TeixeiraN/

    Hybrid model associating thermodynamic calculations and artificial neural network in order to predict molten steel temperature evolution from blowing end of a BOF for secondary metallurgy.

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    The developed model is an association of thermodynamic calculations for dissolution of alloys, slag formers and the deoxidation reaction in the molten steel with two artificial neural network (ANN) models trained with industrial data, to predict the molten steel temperature drop from the blowing end of the BOF until the first measurement at secondary metallurgy. To calculate the associated energy for deoxidation, an experiment was designed to set up the parameters for oxygen partitioning among deoxidants, with timed aluminum addition during teeming being the main parameter. The temperature control in the teeming stage presented a standard deviation for the error of prediction of 5.46 oC, for transportation from the rinsing station to the secondary metallurgy of 2.79 oC. The association of all calculations presented an error standard deviation of 7.49 oC. The operational validation presented superior accuracy compared with the current method for controlling the temperature, resulting in a reduction in the aluminum consumption for heating at secondary metallurgy with a potential economy of U$ 4.07 million per year for a steel shop producing 5 million tons of steel yearly. The artificial neural network model confirmed its capacity for modeling a complex multivariable process and the separation of thermodynamic calculation provides a better adaptability to different steel grades with different teeming strategies

    Deployment of a smart and predictive maintenance system in an industrial case study

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    Industrial manufacturing environments are often characterized as being stochastic, dynamic and chaotic, being crucial the implementation of proper maintenance strategies to ensure the production efficiency, since the machines? breakdown leads to a degradation of the system performance, causing the loss of productivity and business opportunities. In this context, the use of emergent ICT technologies, such as Internet of Things (IoT), machine learning and augmented reality, allows to develop smart and predictive maintenance systems, contributing for the reduction of unplanned machines? downtime by predicting possible failures and recovering faster when they occur. This paper describes the deployment of a smart and predictive maintenance system in an industrial case study, that considers IoT and machine learning technologies to support the online and real-time data collection and analysis for the earlier detection of machine failures, allowing the visualization, monitoring and schedule of maintenance interventions to mitigate the occurrence of such failures. The deployed system also integrates machine learning and augmented reality technologies to support the technicians during the execution of maintenance interventions.2411-78B2-7CDB | Pedro Miguel MoreiraN/

    CT Radiomics in Colorectal Cancer: Detection of KRAS Mutation Using Texture Analysis and Machine Learning

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    In this work, by using descriptive techniques, the characteristics of the texture of the CT (computed tomography) image of patients with colorectal cancer were extracted and, subsequently, classified in KRAS+ or KRAS-. This was accomplished by using different classifiers, such as Support Vector Machine (SVM), Grading Boosting Machine (GBM), Neural Networks (NNET), and Random Forest (RF). Texture analysis can provide a quantitative assessment of tumour heterogeneity by analysing both the distribution and relationship between the pixels in the image. The objective of this research is to demonstrate that CT-based Radiomics can predict the presence of mutation in the KRAS gene in colorectal cancer. This is a retrospective study, with 47 patients from the University Hospital, with a confirmatory pathological analysis of KRAS mutation. The highest accuracy and kappa achieved were 83% and 64.7%, respectively, with a sensitivity of 88.9% and a specificity of 75.0%, achieved by the NNET classifier using the texture feature vectors combining wavelet transform and Haralick coefficients. The fact of being able to identify the genetic expression of a tumour without having to perform either a biopsy or a genetic test is a great advantage, because it prevents invasive procedures that involve complications and may present biases in the sample. As well, it leads towards a more personalized and effective treatmentThis work has received financial support from the Xunta de Galicia (Centro singular de investigación de Galicia, accreditation 2020–2023) and the European Union (European Regional Development Fund—ERDF), Project MTM2016-76969-PS

    Structural mechanical simulation to optimize the sensor arm geometry to be implemented on cranial remodeling orthosis

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    For the treatment of moderate and severe cases of deformational plagiocephaly, an asymmetrical deformation of the skull, a cranial remodeling orthosis (CRO) is used. For the development of a new CRO concept, a pressure sensor grid is placed inside the orthosis that will allow the monitoring of excessive pressures and incorrect CRO positioning throughout the treatment. To implement the sensor grid in the CRO, high mobility of the sensor arms structure that joins the several sensors of this grid is required, however, it is intended that this procedure does not damage the printed copper tracks on the sensor structure. In this study, computer simulations were performed to optimize the sensor arm structure geometry, minimizing undesirable mechanical behavior in the sensor structure when subjected to tensile forces and displacements applied during its placement in the CRO. It was observed that the different sensor arm structures geometries have different effects on the mechanical behavior of the sensor structure when subjected to tensile forces and tensile displacement. The zigzag curve geometry presents the best performance based on high mobility without intense strain on the structure that could damage the printed copper tracks.511F-603F-4B30 | Francisco MirandaN/
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