390 research outputs found

    The portuguese self-administered computerised 24-hour dietary recall

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    Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.Rationale: Measuring the diets of school-aged children is a challenging process. Technology offers the opportunity to automate more accurate methods of dietary assessment, making them less expensive, easier to use and an alternative to nutritionist interviews.info:eu-repo/semantics/publishedVersio

    Fault-Tolerant Control of a Three-Phase Permanent Magnet Synchronous Motor for Lightweight UAV Propellers via Central Point Drive

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    This paper deals with the development and the performance characterization of a novel Fault-Tolerant Control (FTC) aiming to the diagnosis and accommodation of electrical faults in a three-phase Permanent Magnet Synchronous Motor (PMSM) employed for the propulsion of a modern lightweight fixed-wing UAV. To implement the fault-tolerant capabilities, a four-leg inverter is used to drive the reference PMSM, so that a system reconfiguration can be applied in case of a motor phase fault or an inverter fault, by enabling the control of the central point of the three-phase connection. A crucial design point is to develop Fault-Detection and Isolation (FDI) algorithms capable of minimizing the system failure transients, which are typically characterized by high-amplitude high-frequency torque ripples. The proposed FTC is composed of two sections: in the first, a deterministic model-based FDI algorithm is used, based the evaluation of the current phasor trajectory in the Clarke’s plane; in the second, a novel technique for fault accommodation is implemented by applying a reference frame transformation to post-fault commands. The FTC effectiveness is assessed via detailed nonlinear simulation (including sensors errors, digital signal processing, mechanical transmission compliance, propeller loads and electrical faults model), by characterizing the FDI latency and the post-fault system performances when open circuit faults are injected. Compared with reports in the literature, the proposed FTC demonstrates relevant potentialities: the FDI section of the algorithm provides the smallest ratio between latency and monitoring samples per electrical period, while the accommodation section succeeds in both eliminating post-fault torque ripples and maintaining the mechanical power output with negligible efficiency degradation

    Novel approach to fault-tolerant control of inter-turn short circuits in permanent magnet synchronous motors for UAV propellers

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    This paper deals with the development of a novel fault‐tolerant control technique aiming at the diagnosis and accommodation of inter‐turn short circuit faults in permanent magnet synchronous motors for lightweight UAV propulsion. The reference motor is driven by a four‐leg converter, which can be reconfigured in case of a phase fault by enabling the control of the central point of the motor Y‐connection. A crucial design point entails the development of fault detection and isolation (FDI) algorithms capable of minimizing the failure transients and avoiding the short circuit extension. The proposed fault‐tolerant control is composed of two sections: the first one applies a novel FDI algorithm for short circuit faults based on the trajectory tracking of the motor current phasor in the Clarke plane; the second one implements the fault accommodation, by applying a reference frame transformation technique to the post‐fault commands. The control effectiveness is assessed via nonlinear simulations by characterizing the FDI latency and the post‐fault performances. The proposed technique demonstrates excellent potentialities: the FDI algorithm simultaneously detects and isolates the considered faults, even with very limited extensions, during both stationary and unsteady operating conditions. In addition, the proposed accommodation technique is very effective in minimizing the post‐fault torque ripples

    A finer print than TADs: PRC1-mediated domains

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    Polycomb proteins are well-known epigenetic repressors with unexplained roles in chromatin folding. In this issue of Molecular Cell, Kundu et al. (2017) investigate the structures of PRC1-mediated domains in stem cells and probe their changes upon differentiation and in PRC knockouts

    Enhancing Social-Ecological Resilience in Indonesia: A Case of North Pekalongan District, Central Java

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    In the last eight years (2008-2016), some areas in the northern part of Pekalongan have been experiencing coastal inundation. There have been social, economic and physical disruptions caused by coastal inundation particularly on built environments, paddy fields, and fishpond. The capacity of these areas to provide support for community livelihood has decreased significantly. This accumulative environmental change leads to the emergence of vulnerable regions which are characterized by limited social and ecological capacity to respond hazards. In order to enhance the social-ecological resilience, it is necessary to identify how the community has elevated their capacity and improved their livelihood. This paper presents empirical evidence of various pathways on how the community has transformed their capacity to respond to the changing environment due to coastal inundation. Following case study approach, this paper explores how the community has learned from their experiences, knowledge, and efforts from the past, and transformed them into a better understanding to cope with, to adapt to, and to become resilient from coastal inundation. The research applied in-depth interviews involving key persons selected through purposive and snowballing samplings. They represented the most capable person in each sub-district whose important data and information related to coastal inundation at the individual, household, and community organization levels belong to. The scope of area observation was limited to six sub-districts adjacent to the coast in the North Pekalongan District. The results showed that social-ecological resilience is likely to enhance in a community with flexible networking building capability. Such networking is beneficial to spreading out the important information, novel knowledge and practical tools and solutions to the community. These are the key elements for new transformative pathways. However, there remain various community capacities with different achievements on transformative pathways necessary to the future empowerment initiatives. Only a few communities in Kandang Panjang Sub-district who have performed a short-term resilience due to their awareness on establishing social networking and several actions on environmental quality improvements

    Pemanfaatan Constructed Wetland Sebagai Bagian Dari Rancangan Lansekap Ruang Publik Yang Berwawasan Ekologis Studi Kasus Houtan Park China

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    Kebutuhan akan air bersih merupakan salah satu permasalahan lingkungan yang sering terjadi. Hal ini sejalan dengan kebutuhan akan kualitas lingkungan yang lebih baik, khususnya dalam kasus ruang luar atau lansekap. Lansekap berbasis suasana air merupakan satu bentuk ruang luar yang memiliki keistimewaan sekaligus tantangan, terkait kualitas air dan model pembersihannya. Dari berbagai metode pembersihan air yang ada, Constructed Wetland merupakan suatu bentuk pembersihan kondisi air alamiah dengan meniru wetland alamiah baik dari segi struktur pewadahannya maupun vegetasi – vegetasi yang digunakan.Paper ini bertujuan untuk mengetahui penerapan upaya pembersihan air secara alami menggunakan metode constructed wetland, dan melihat pemanfaatan metode ini dalam integrasinya dengan rancangan lansekap. Penelitian bersifat kualitatif dengan Metode penelitian deskriptif, melalui studi literature dan kasus di Houtan Park, China.Dari hasil penelitian ini disimpulkan bahwa sebagai pilihan metode pembersihan air secara alamiah, ruang dan suasana yang tercipta dari sistem ini berpotensi untuk dikembangkan menjadi bagian dari konsep rancangan lansekap. Dalam studi kasus di Houtan park, Shanghai, China, constructed wetland tidak hanya dimanfaatkan sebagai sarana pembersihan air, namun menjadi bagian dari area lansekap ruang publik yang dapat dinikmati dan membuat pengunjung lebih dekat dengan alam dan lingkungan yang berkualitas

    Eat Mediterranean: um programa para reduzir desigualdades nutricionais em refeições escolares

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    Enquadramento do Projeto “Eat Mediterranean”: Intervenção comunitária para redução das desigualdades nutricionais em meio escolar de promoção da Dieta Mediterrânica; Pretendeu: - Constituir um modelo ecológico comunitário - Melhorar oferta alimentar - Reduzir desvios do Estado Nutricional nos alunos - Capacitar Comunidade Educativa e Profissionais de Saúde e Educação para a Dieta Mediterrânica; Estratégia de intervenção da OMS, priorizando o meio escolar, assente em rede de parcerias - saúde/educação/municípios; Alinhado com Programas Nacionais Promoção Alimentação Saudável e Saúde Escolar.Promotor: Administração Regional de Saúde de Lisboa e Vale do Tejo, I.P. Parcerias: Agrupamento de Escolas Dr. Ginestal Machado, Agrupamento de Escolas Sá da Bandeira, Agrupamento de Escolas de José Relvas, Centro de Estudos e Investigação em Dinâmicas Sociais e Saúde, ISCTE - Instituto Universitário de Lisboa, Município de Alpiarça, Município de Santarém, INSA – Instituto Nacional de Saúde Dr. Ricardo JorgeN/

    Investigation of Radiation-Induced Toxicity in Head and Neck Cancer Patients through Radiomics and Machine Learning: A Systematic Review

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    Background. Radiation-induced toxicity represents a crucial concern in oncological treatments of patients affected by head and neck neoplasms, due to its impact on survivors' quality of life. Published reports suggested the potential of radiomics combined with machine learning methods in the prediction and assessment of radiation-induced toxicities, supporting a tailored radiation treatment management. In this paper, we present an update of the current knowledge concerning these modern approaches. Materials and Methods. A systematic review according to PICO-PRISMA methodology was conducted in MEDLINE/PubMed and EMBASE databases until June 2019. Studies assessing the use of radiomics combined with machine learning in predicting radiation-induced toxicity in head and neck cancer patients were specifically included. Four authors (two independently and two in concordance) assessed the methodological quality of the included studies using the Radiomic Quality Score (RQS). The overall score for each analyzed study was obtained by the sum of the single RQS items; the average and standard deviation values of the authors' RQS were calculated and reported. Results. Eight included papers, presenting data on parotid glands, cochlea, masticatory muscles, and white brain matter, were specifically analyzed in this review. Only one study had an average RQS was ≤ 30% (50%), while 3 studies obtained a RQS almost ≤ 25%. Potential variability in the interpretations of specific RQS items could have influenced the inter-rater agreement in specific cases. Conclusions. Published radiomic studies provide encouraging but still limited and preliminary data that require further validation to improve the decision-making processes in preventing and managing radiation-induced toxicities
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