876 resultados para Maximal Aerobic Speed
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This paper is on an onshore variable speed wind turbine with doubly fed induction generator and under supervisory control. The control architecture is equipped with an event-based supervisor for the supervision level and fuzzy proportional integral or discrete adaptive linear quadratic as proposed controllers for the execution level. The supervisory control assesses the operational state of the variable speed wind turbine and sends the state to the execution level. Controllers operation are in the full load region to extract energy at full power from the wind while ensuring safety conditions required to inject the energy into the electric grid. A comparison between the simulations of the proposed controllers with the inclusion of the supervisory control on the variable speed wind turbine benchmark model is presented to assess advantages of these controls. (C) 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
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Energy efficiency plays an important role to the CO2 emissions reduction, combating climate change and improving the competitiveness of the economy. The problem presented here is related to the use of stand-alone diesel gen-sets and its high specific fuel consumptions when operates at low loads. The variable speed gen-set concept is explained as an energy-saving solution to improve this system efficiency. This paper details how an optimum fuel consumption trajectory based on experimentally Diesel engine power map is obtained.
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The authors studied 58 infants hospitalized for pneumonia in a semi-intensive care unit. Age ranged from 1 complete to 6 incomplete months. The infants were sent from another hospital in 20 cases and from home in a further 38. Pulmonary involvement, which was alveolar in 46 cases and interstitial in 12, was bilateral in 31 children. The investigation was carried out prospectively on the etiological agents associated with respiratory infection to look for evidence of aerobic bacteria (blood cultures), Chlamydia trachomatis and Cytomegalovirus (serology), and Pneumocystis carinii (direct microscopy of tracheal aspirated material). The following infectious agents were diagnosed in 21 children (36.2%): Aerobic bacteria (8), Chlamydia trachomatis (5), Pneumocystis carinii (3), Cytomegalovirus (3), Cytomegalovirus and Chlamydia trachomatis (1), Aerobic bacteria and Cytomegalovirus (1). Seven cases of infection by Chlamydia trachomatis and/or Cytomegalovirus were diagnosed out of the 12 cases with pulmonary interstitial involvement.
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Wind speed forecasting has been becoming an important field of research to support the electricity industry mainly due to the increasing use of distributed energy sources, largely based on renewable sources. This type of electricity generation is highly dependent on the weather conditions variability, particularly the variability of the wind speed. Therefore, accurate wind power forecasting models are required to the operation and planning of wind plants and power systems. A Support Vector Machines (SVM) model for short-term wind speed is proposed and its performance is evaluated and compared with several artificial neural network (ANN) based approaches. A case study based on a real database regarding 3 years for predicting wind speed at 5 minutes intervals is presented.
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RESUMO: Introdução: O treino de exercício assume uma importância fundamental nos programas de reabilitação respiratória, contudo permanece desconhecida qual a intensidade de treino efectiva na mudança dos resultados centrados no doente. Objectivos: Foram estudados os efeitos de duas intensidades de treino aeróbio na qualidade de vida relacionada com a saúde, no controlo de sintomas e na tolerância ao exercício, num programa de reabilitação respiratória para doentes com DPOC. Métodos: Trinta e quatro doentes com DPOC de estádios GOLD de ligeiro a muito grave, foram alocados aleatoriamente a intensidades de treino de exercício aeróbio de 60% ou 80% da intensidade máxima avaliada na prova de esforço num programa ambulatório de reabilitação respiratória de 20 sessões. Foram avaliados resultados centrados no doente pela aplicação do questionário respiratório de St.George, do índice de dispneia de Mahler, do questionário de actividades da vida diária do London Chest, da prova de 6 minutos, da prova de endurance a carga constante e da prova de esforço máxima incremental. Resultados: Apesar de existirem melhorias significativas em todos os resultados para ambos os grupos, a diferença média intergrupal por efeito da intensidade de treino aeróbio a 60% ou 80% da carga máxima em prova de esforço não foi significativa no questionário respiratório de St.George (p=0,306), no índice de dispneia de Mahler (p=0,378), no questionário de actividades da vida diária do London Chest (p=0,425), na prova de marcha de 6 minutos (p=0,917), na prova de endurance a carga constante (p=0,504) e na prova de esforço máxima incremental (p=0,117). Verificou-se ainda que a média das diferenças intergrupais na prova de endurance a carga constante e na prova de marcha de 6 minutos não apresentou qualquer associação com a idade dos doentes. Conclusões: O estudo permite concluir que não existem diferenças significativas nas alterações médias da qualidade de vida relacionada com a saúde, do controle de sintomas e da tolerância ao exercício em doentes com DPOC como efeito de duas intensidades de treino aeróbio. Os autores propõem para a prática clínica em reabilitação respiratória, a aplicação de intensidades de treino aeróbio individualmente adaptadas, de pelo menos 60% da carga máxima na prova de esforço inicial. -------------------------------ABSTRACT: Introduction: Exercise training is an important component of pulmonary rehabilitation, but it remains questionable as how training intensity changes patient-centered outcomes. Aims and objectives: The effects of two aerobic exercise training intensities in health-related quality of life, symptoms control and exercise tolerance in COPD patients were studied. Methods: Thirty-four COPD patients from mild to very severe GOLD stages were randomly assigned to a 60% or 80% aerobic exercise training intensity in a twenty-session outpatient pulmonary rehabilitation program. Patient-centered outcomes were assessed with St.George's respiratory questionnaire, Mahler dyspnoea index, London Chest activity of daily living, six minute walk test, constant work rate test and maximal incremental test. Results: Although there were significant improvements in all outcomes for both groups, there were no differences in mean change in St.George's respiratory questionnaire (p=0,306), Mahler dyspnoea index (p=0,378), London Chest activity of daily living (p=0,917), six-minute walk test (p=0,504), constant work rate test (p=0,504) and maximal incremental test (p=0,117), as an effect of aerobic exercise training intensity of 60% or 80%. Mean changes in constant work rate and six-minute walk test were not age-related. Conclusions: It is concluded that there are no differences in mean changes in health-related quality of life, symptoms control and exercise tolerance in COPD patients as an effect of two aerobic exercise training intensities. Therefore, the authors suggest that individually tailored exercise intensities above 60% should guide clinical practice in pulmonary rehabilitation.
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Anxiety disorders are the most common psychiatric disorders observed currently. It is a normal adaptive response to stress that allows coping with adverse situations. Nevertheless, when anxiety becomes excessive or disproportional in relation to the situation that evokes it or when there is not any special object directed at it, such as an irrational dread of routine stimuli, it becomes a disabling disorder and is considered to be pathological. The traditional treatment used is medication and cognitive behavioral psychotherapy, however, last years the practice of physical exercise, specifically aerobic exercise, has been investigated as a new non-pharmacological therapy for anxiety disorders. Thus, the aim of this article was to provide information on research results and key chains related to the therapeutic effects of aerobic exercise compared with other types of interventions to treat anxiety, which may become a useful clinical application in a near future. Researches have shown the effectiveness of alternative treatments, such as physical exercise, minimizing high financial costs and minimizing side effects. The sample analyzed, 66.8% was composed of women and 80% with severity of symptoms anxiety as moderate to severe. The data analyzed in this review allows us to claim that alternative therapies like exercise are effective in controlling and reducing symptoms, as 91% of anxiety disorders surveys have shown effective results in treating. However, there is still disagreement regarding the effect of exercise compared to the use of antidepressant symptoms and cognitive function in anxiety, this suggests that there is no consensus on the correct intensity of aerobic exercise as to achieve the best dose-response, with intensities high to moderate or moderate to mild.
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The pathophysiology of depression is related to neurobiological changes that occur in the monoamine system, hypothalamic-pituitary-adrenal axis, neurogenesis system and the neuroimmune system. In recent years, there has been a growing interest in the research of the effects of exercise on brain function, with a special focus on its effects on brainderived neurotrophic factor (BDNF), cortisol and other biomarkers. Thus, the aim of this study is to present a review investigating the acute and chronic effects of aerobic exercise on BDNF and cortisol levels in individuals with depression. It was not possible to establish an interaction between aerobic exercise and concentration of BDNF and cortisol, which may actually be the result of the divergence of methods, such as type of exercises, duration of the sessions, and prescribed intensity and frequency of sessions.
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Depression is a common and disabling disease that affects over 100 million people worldwide and can have a significant impact on physical and mental health, reducing their quality of life. Thus, the aim of this article was to provide information on research results and key chains related to the therapeutic effects of chronic aerobic exercise compared with other types of interventions to treat depression, which may become a useful clinical application in a near future. Researches have shown the effectiveness of alternative treatments, such as physical exercise, minimizing high financial costs and minimizing side effects. In this review, the data analyzed allows us to claim that alternative therapies, such as exercise, are effective on controlling and reducing symptoms. 69.3% of the studies that investigated the antidepressant effects of exercise on depressive were significant, and the other 30.7% of the studies improved only in general physiological aspects, such as increased oxygen uptake, increased use of blood glucose and decreased body fat percentage, with no improvement on symptoms of depression. From the sample analyzed, 71.4% was composed of women, and regarding the severity of symptoms, 85% had mild to moderate depression and only 15% had moderate to severe depression. However, there is still disagreement regarding the effect of exercise compared to the use of antidepressants in symptomatology and cognitive function in depression, this suggests that there is no consensus on the correct intensity of aerobic exercise as to achieve the best dose-response, with intensities high to moderate or moderate to mild.
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Objective: To analyze the short- and long-term effects of microcurrent used with aerobic exercise on abdominal fat (visceral and subcutaneous). Methods: Forty-two female students from a university population were randomly assigned into five group: intervention group (IG) 1 (n=9), IG2 (n=9), IG3 (n=7), IG4 (n=8), and placebo group (PG) (n=9). An intervention program of 10 sessions encompassing microcurrent and aerobic exercise (performed with a cycloergometer) was applied in all groups, with slightly differences between them. In IG1 and IG2, microcurrent with transcutaneous electrodes was applied, with different frequency values; 30-minute exercise on the cycloergometer was subsequently performed. IG3 used the same protocol as IG1 but with different electrodes (percutaneous), while in IG4 the microcurrent was applied simultaneously with the cycloergometer exercise. Finally, the PG used the IG1 protocol but with the microcurrent device switched off. All groups were evaluated through ultrasound and abdominal perimeter measurement for visceral and subcutaneous abdominal fat assessment; through calipers for skinfolds measurement; through bioimpedance to evaluate weight, fat mass percentage, and muscular mass; and through blood analyses to measure cholesterol, triglyceride, and glucose levels. Results: After intervention sessions, visceral fat decreased significantly in IG1 compared with the PG. Subcutaneous fat was reduced significantly in all groups compared with the PG. After 4 weeks, almost all results were maintained. Conclusion: The addition of microcurrent to aerobic exercise may reduce fat more than does aerobic exercise alone.
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The present article is based on the report for the Doctoral Conference of the PhD programme in Technology Assessment, held at FCT-UNL Campus, Monte de Caparica, June 9th, 2011. The PhD thesis has the supervision of Prof. António Moniz (FCT-UNL and ITAS-KIT), and co-supervision of Prof. Manuel Seabra Pereira and Prof. Rosário Macário (both from IST-UTL).
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To determine whether the slope of a maximal bronchial challenge test (in which FEV1 falls by over 50%) could be extrapolated from a standard bronchial challenge test (in which FEV1 falls up to 20%), 14 asthmatic children performed a single maximal bronchial challenge test with methacholin(dose range: 0.097–30.08 umol) by the dosimeter method. Maximal dose-response curves were included according to the following criteria: (1) at least one more dose beyond a FEV1 ù 20%; and (2) a MFEV1 ù 50%. PD20 FEV1 was calculated, and the slopes of the early part of the dose-response curve (standard dose-response slopes) and of the entire curve (maximal dose-response slopes) were calculated by two methods: the two-point slope (DRR) and the least squares method (LSS) in % FEV1 × umol−1. Maximal dose-response slopes were compared with the corresponding standard dose-response slopes by a paired Student’s t test after logarithmic transformation of the data; the goodness of fit of the LSS was also determined. Maximal dose-response slopes were significantly different (p < 0.0001) from those calculated on the early part of the curve: DRR20% (91.2 ± 2.7 FEV1% z umol−1)was 2.88 times higher than DRR50% (31.6 ± 3.4 DFEV1% z umol−1), and the LSS20% (89.1 ± 2.8% FEV1 z umol−1) was 3.10 times higher than LSS 50% (28.8 ± 1.5%FEV1 z umol−1). The goodness of fit of LSS 50% was significant in all cases, whereas LSS 20% failed to be significant in one. These results suggest that maximal dose-response slopes cannot be predicted from the data of standard bronchial challenge tests.
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Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Electrical and Computer Engineering of the Faculdade de Ciências e Tecnologia of Universidade Nova de Lisboa
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BACKGROUND: Few randomised studies have compared antiandrogen intermittent hormonal therapy (IHT) with continuous maximal androgen blockade (MAB) therapy for advanced prostate cancer (PCa). OBJECTIVE: To determine whether overall survival (OS) on IHT (cyproterone acetate; CPA) is noninferior to OS on continuous MAB. DESIGN, SETTING, AND PARTICIPANTS: This phase 3 randomised trial compared IHT and continuous MAB in patients with locally advanced or metastatic PCa. INTERVENTION: During induction, patients received CPA 200 mg/d for 2 wk and then monthly depot injections of a luteinising hormone-releasing hormone (LHRH; triptoreline 11.25 mg) analogue plus CPA 200 mg/d. Patients whose prostate-specific antigen (PSA) was <4 ng/ml after 3 mo of induction treatment were randomised to the IHT arm (stopped treatment and restarted on CPA 300 mg/d monotherapy if PSA rose to ≥20 ng/ml or they were symptomatic) or the continuous arm (CPA 200 mg/d plus monthly LHRH analogue). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Primary outcome measurement was OS. Secondary outcomes included cause-specific survival, time to subjective or objective progression, and quality of life. Time off therapy in the intermittent arm was recorded. RESULTS AND LIMITATIONS: We recruited 1045 patients, of which 918 responded to induction therapy and were randomised (462 to IHT and 456 to continuous MAB). OS was similar between groups (p=0.25), and noninferiority of IHT was demonstrated (hazard ratio [HR]: 0.90; 95% confidence interval [CI], 0.76-1.07). There was a trend for an interaction between PSA and treatment (p=0.05), favouring IHT over continuous therapy in patients with PSA ≤1 ng/ml (HR: 0.79; 95% CI, 0.61-1.02). Men treated with IHT reported better sexual function. Among the 462 patients on IHT, 50% and 28% of patients were off therapy for ≥2.5 yr or >5 yr, respectively, after randomisation. The main limitation is that the length of time for the trial to mature means that other therapies are now available. A second limitation is that T3 patients may now profit from watchful waiting instead of androgen-deprivation therapy. CONCLUSIONS: Noninferiority of IHT in terms of survival and its association with better sexual activity than continuous therapy suggest that IHT should be considered for use in routine clinical practice.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
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Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores