309 research outputs found

    PUGeo-Net: A Geometry-centric Network for 3D Point Cloud Upsampling

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    This paper addresses the problem of generating uniform dense point clouds to describe the underlying geometric structures from given sparse point clouds. Due to the irregular and unordered nature, point cloud densification as a generative task is challenging. To tackle the challenge, we propose a novel deep neural network based method, called PUGeo-Net, that learns a 3×33\times 3 linear transformation matrix T\bf T for each input point. Matrix T\mathbf T approximates the augmented Jacobian matrix of a local parameterization and builds a one-to-one correspondence between the 2D parametric domain and the 3D tangent plane so that we can lift the adaptively distributed 2D samples (which are also learned from data) to 3D space. After that, we project the samples to the curved surface by computing a displacement along the normal of the tangent plane. PUGeo-Net is fundamentally different from the existing deep learning methods that are largely motivated by the image super-resolution techniques and generate new points in the abstract feature space. Thanks to its geometry-centric nature, PUGeo-Net works well for both CAD models with sharp features and scanned models with rich geometric details. Moreover, PUGeo-Net can compute the normal for the original and generated points, which is highly desired by the surface reconstruction algorithms. Computational results show that PUGeo-Net, the first neural network that can jointly generate vertex coordinates and normals, consistently outperforms the state-of-the-art in terms of accuracy and efficiency for upsampling factor 4164\sim 16.Comment: 17 pages, 10 figure

    Arm-in-cage testing of natural human-derived mosquito repellents

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    BACKGROUND: Individual human subjects are differentially attractive to mosquitoes and other biting insects. Previous investigations have demonstrated that this can be attributed partly to enhanced production of natural repellent chemicals by those individuals that attract few mosquitoes in the laboratory. The most important compounds in this respect include three aldehydes, octanal, nonanal and decanal, and two ketones, 6-methyl-5-hepten-2-one and geranylacetone [(E)-6,10-dimethylundeca-5,9-dien-2-one]. In olfactometer trials, these compounds interfered with attraction of mosquitoes to a host and consequently show promise as novel mosquito repellents. METHODS: To test whether these chemicals could provide protection against mosquitoes, laboratory repellency trials were carried out to test the chemicals individually at different concentrations and in different mixtures and ratios with three major disease vectors: Anopheles gambiae, Culex quinquefasciatus and Aedes aegypti. RESULTS: Up to 100% repellency was achieved depending on the type of repellent compound tested, the concentration and the relative composition of the mixture. The greatest effect was observed by mixing together two compounds, 6-methyl-5-hepten-2-one and geranylacetone in a 1:1 ratio. This mixture exceeded the repellency of DEET when presented at low concentrations. The repellent effect of this mixture was maintained over several hours. Altering the ratio of these compounds significantly affected the behavioural response of the mosquitoes, providing evidence for the ability of mosquitoes to detect and respond to specific mixtures and ratios of natural repellent compounds that are associated with host location. CONCLUSION: The optimum mixture of 6-methyl-5-hepten-2-one and geranylacetone was a 1:1 ratio and this provided the most effective protection against all species of mosquito tested. With further improvements in formulation, selected blends of these compounds have the potential to be exploited and developed as human-derived novel repellents for personal protection

    Knowledge, experience, and potential risks of dating violence among Japanese university students: a cross-sectional study

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    <p>Abstract</p> <p>Background</p> <p>The Domestic Violence Prevention Act came into effect in Japan in 2001, but covers only marriage partner violence and post-divorce partner violence, and does not recognize intimate partner violence (IPV). The present study was performed to determine the experience of harassment, both toward and from an intimate partner, and recognition of harassment as IPV among Japanese university students.</p> <p>Methods</p> <p>A self-administered questionnaire survey regarding the experience of harassment involving an intimate partner was conducted as a cross-sectional study among freshman students in a prefectural capital city in Japan.</p> <p>Results</p> <p>A total of 274 students participated in the present study. About half of the subjects (both male and female students) had experience of at least one episode of harassment toward or had been the recipient of harassment from an intimate partner. However, the study participants did not recognize verbal harassment, controlling activities of an intimate partner, and unprotected sexual intercourse as violence. Experience of attending a lecture/seminar about domestic violence and dating violence did not contribute to appropriate help-seeking behavior.</p> <p>Conclusions</p> <p>An educational program regarding harassment and violence prevention and appropriate help-seeking behavior should be provided in early adolescence to avoid IPV among youth.</p

    Estudio longitudinal de lesiones deportivas en practicantes de gimnasia aeróbica de competición

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    Introduction: Aerobic gymnastics, since its membership in the International Gymnastics Federation, has undergone changes in its regulations. Objective: To analyze the injuries found in Spanish aerobic gymnastics athletes during different editions of the Code of Points. Methods: A descriptive, longitudinal and compara-tive study was carried out on the epidemiology of injuries in aerobic gymnastics published during different editions of the Code of Points. Results: It highlights that the number of injuries decreased from 156 to 38 last year. This decline has been related to the restriction on the number of difficulties in the exercise and the number of elements to be performed on the floor. However, they have increased the number and value of the difficulties. Conclusions: Therefore, it is concluded that the changes made in the regulations are intended to safeguard the health of athletes and ensure that competition develops at its best artistic and technical aspect.Introdução: A ginástica aeróbica, desde sua adesão à Federação Internacional de Ginástica, passou por mudanças em seus regulamentos. Objetivo: Analisar as lesões encontradas nos atletas espanhóis de ginástica aeróbica durante as diferentes edições do Código de Pontos. Métodos: Realizou-se um estudo descritivo, longitudinal e comparativo sobre a epidemiologia de lesões na ginástica aeróbica publicado durante as diferentes edições do Código de Pontos. Resultados Salienta-se que o número de lesões diminuiu de 156 para 38 no ano passado. Este declínio tem sido relacionado com a limitação do número de dificuldades no exercício e o número de elementos a serem feitos no solo. No entanto, eles aumentaram o número e valor das dificuldades. Conclusões: Portanto, concluiu-se que as modificações feitas nos regulamentos destinam-se a salvaguardar a saúde dos atletas e garantir que a competição se desenvolva no seu melhor aspecto artístico e técnico.Introducción: La gimnasia aeróbica desde su pertenencia a la Federación Internacional de Gimnasia ha sufrido cam-bios en su reglamentación. Objetivo: Analizar las lesiones que los deportistas españoles de gimnasia aeróbica presentaron durante las diferentes ediciones del Código de Puntuación. Métodos: Se ha realizado un estudio descriptivo, longitudinal y comparativo sobre la epidemiología de las lesiones en la gimnasia aeróbica publicado durante las diferentes ediciones del Código de Puntuación. Resultados: El estudio destaca la disminución del número de lesiones, de 156 a 38 en el último año. Esta disminución ha tenido relación con la restricción del número de dificultades en el ejercicio y la cantidad de elementos a realizar en el suelo. Sin embargo, han aumentado el número y el valor de las dificultades. Conclusiones: Por tanto, han concluido que las modificaciones que se realizan en la reglamentación tienen como objetivo velar por la salud de los deportistas y garantizar que la competición se desarrolle en su máximo esplendor artístico y técnico

    Going it alone won’t work! The relational imperative for social innovation in social enterprises

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    Shifts in the philosophy of the “state” and a growing emphasis on the “Big Society” have placed an increasing onus on a newly emerging organizational form, social enterprises, to deliver innovative solutions to ease societal issues. However, the question of how social enterprises manage the process of social innovation remains largely unexplored. Based on insights from both in-depth interviews and a quantitative empirical study of social enterprises, this research examines the role of stakeholder relationships in supporting the process of social innovation within social enterprises. We find that social enterprises are adept at working with their stakeholders in the ideation stage of social innovation. In contrast, they often fail to harness knowledge and expertise from their partners during the social innovation implementation phase. Consequently, we propose a social innovation–stakeholder relationship matrix that provides social enterprises in particular with insight for developing stakeholder relationships to achieve their social innovation missions
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