Otimização das leis de manobra de comportas dos circuitos de enchimento e esgotamento de eclusas de navegação

The main objective of this thesis is the development of a new method for the optimization of navigation lock aqueduct control gate operation rules, using numerical methods taken from Operations Research. As a component step for the obtention of a general model, a simplified model corresponding to no air inception and variable speed gate operation was developped. The simplified model has the objective of determining the optimal gate operation rule which minimizes total lock filling or emptying time and satisfies the following constraints: - cavitation control no air inception; - maximum gate operation speed for opening or closure is specified; - maximum values of water level raise or drawdown velocity are specified. The technique used is the successive linearization of the problem equations and application of the Simplex Algorithm. The efficiency of this method was tested on the example of the Promiss Powerplant Navigation Lock. ln order to obtain more general conclusions and a comparison between different locks, a formulation using dimensionless variables was also proposed and developped. For the purpose of integrating numericalIy the equation of the surges, the use of a Laplace Transform technique was found to be highly accurate, efficient and stable. Finally, a number of recommendations are presented for future research work. One of the objectives is the establishment of simple relationships between optimal gate operation rules and lock characteristics.Este trabalho de tese tem como objetivo o desenvolvimento de uma metodologia para otimização de leis de manobra de comportas dos circuitos de enchimento e esgotamento de eclusas de navegação, com base na Teoria da Otimização. Tendo por objetivo último a obtenção de um modelo matemático aplicável a qualquer eclusa, foi desenvolvido um modelo representativo de situações em que a aeração do escoamento pelo aqueduto não é permitida, e as comportas de controle do escoamento podem ser acionadas com qualquer velocidade, limitada a um valor máximo. O modelo tem por princípio a determinação da lei de manobra das comportas que minimiza o tempo de enchimento ou esgotamento da câmara da eclusa, sujeito às restrições devidas ao controle da cavitação, à máxima velocidade ascencional do nível d'água e a máxima velocidade de abertura ou fechamento das comportas. Utiliza-se uma técnica de linearizações sucessivas, associada à programação linear, para a resolução do problema. O modelo desenvolvido foi aplicado ao caso da Eclusa de Promissão, verificando-se a eficiência da metodologia adotada. A formulação matemática do problema também foi feita utilizando-se variáveis adimensionais. Desta forma, torna-se possível uma comparação de resultados de eclusas com características diferentes, resultando em um passo à generalização do processo de otimização. Demonstra-se ainda o interesse na utilização da Transformada de Laplace para resolução numérica da equação diferencial que representa o escoamento transitório nos aquedutos de uma eclusa. Foram verificadas vantagens em termos de eficiência, estabilidade e precisão numérica. Apresentam-se, finalmente, recomendações para a continuação de pesquisas sobre o assunto. Um dos intuitos é a obtenção de dados para elaboração de um ábaco, que possibilite a determinação da lei ótima de manobra de forma gráfica, bastando para isso o cálculo de alguns parâmetros específicos de cada eclusa

Microbial Ecosystem Analysis in Root Canal Infections Refractory to Endodontic Treatment

Introduction To combine Multiple Displacement Amplification (MDA) and checkerboard DNA–DNA hybridization to qualitatively and quantitatively evaluate the microbiota present in infections refractory to endodontic treatment. Methods The subjects of this study were 40 patients presenting periapical lesions refractory to endodontic treatment. Samples were taken by scraping or filing root canal walls with a #10 K-type hand file. Sample DNA was amplified by MDA, and the levels of 107 bacterial taxa were analyzed by checkerboard DNA–DNA hybridization. The taxa were divided into three distinct microbial populations, depending on their mean proportion in samples (% DNA probe counts ± SEM), as follows: dominant (≥3.0%), sub-dominant (\u3e1.6 to 3.0%) and residual (≤1.6%) populations. The significance of differences was determined using the Mann-Whitney test. Results The taxa present with the highest mean proportions (constituting the dominant population) were Corynebacterium diphtheriae (8.03±0.98), Porphyromonas gingivalis (5.42±2.09), Streptococcus sobrinus (5.33±0.69), and Stenotrophomonas maltophilia (4.72±1.73). Among the sub-dominant population were Eubacterium saphenum (3.85±1.06), Helicobacter pylori (3.16±0.62), Dialister pneumosintes (3.12±1.1), Clostridium difficile (2.74±0.41), Enterobacter agglomerans (2.64±0.54), Salmonella enterica (2.51±0.52), Mobiluncus mulieris (2.44±0.6), and Klebsiella oxytoca (2.32±0.66). In the population of bacteria present at the lowest mean proportions (the residual population), Bacteroides ureolyticus (0.04±0.01), Haemophilus influenzae (0.04±0.02), and Prevotella oris (0.01±0.01) were found at the lowest mean proportions. Enterococcus faecalis was detected in the residual population (0.52±0.26). Conclusion The microbial climax community in teeth refractory to endodontic treatment not only harbor medically important species, but also contains distinct microbial consortia present with different population levels

Impact of urbanization and land use on wet weather discharge of small catchments in Belo Horizonte (Brazil)

International audienc

Impact of urbanisation (trends) on runoff behaviour of Pampulha watersheds (Brazil)

International audienceThe paper presents an analysis of runoff behaviour of four urban catchments between the municipalities of Belo Horizonte and Contagem in Brazil, linked to their land use. Two years of online measurement of flow data, combined with spatial analysis, was linked through runoff modelisation with EPA SWMM. The coefficients of Nash obtained varying between 0.75 and 0.87 demonstrated an adequate modelling approach. A 1-year rain series was applied to evaluate the runoff behaviour of actual land cover and that of 2002. The peak flows normalised to watershed surfaces revealed as the most urbanised (85%) watershed Ressaca with 178 L/ha/s, three times more runoff intensive than the least urbanised (41%) Mergulhão with 67 L/ha/s. Statistical analysis of land cover data and modelling results on watershed and sub-watershed level showed main correlations between hydrological parameters such as peak flow, average event flow and restitution time, but also between land cover and runoff coefficient. This approach gave a linear relation between runoff and green surface, with a runoff coefficient of 0.86 for fully urbanised zone and 0.43 for full “green” cover. Prospective simulation with actual urbanisation rates varying from 4 to 34 ha/year suggested an increase between 6 and 18% of the flows and a possible end of urbanisation within the next two to three decades. These findings should contribute to a better understanding of hydrological impact of Belo Horizonte urbanisation and to the restauration of its Lake Pampulha

Cost-effectiveness of photobiomodulation therapy for the prevention and management of cancer treatment toxicities: a systematic review

To identify and summarize the evidence on the cost-effectiveness of photobiomodulation (PBM) therapy for the prevention and treatment of cancer treatment-related toxicities. This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA) and Meta-analysis Of Observational Studies in Epidemiology (MOOSE). Scopus, MEDLINE/PubMed, and Embase were searched electronically. A total of 1490 studies were identified, and after a two-step review, 4 articles met the inclusion criteria. The included studies analyzed the cost-effectiveness of PBM therapy used in the context of lymphedema for breast cancer and oral mucositis (OM) induced by chemotherapy and radiotherapy. Better outcomes were associated with PBM therapy. The incremental cost-effectiveness ratio ranged from 3050.75 USD to 5592.10 USD per grade 3–4 OM case prevented. PBM therapy cost 21.47 USD per percentage point reduction in lymphedema in comparison with 80.51 USD for manual lymph drainage and physical therapy. There is limited evidence that PBM therapy is cost-effective in the prevention and treatment of specific cancer treatment-related toxicities, namely, OM and breast cancer-related lymphedema. Studies may have underreported the benefits due to a lack of a comprehensive cost evaluation. This suggests a wider acceptance of PBM therapy at cancer treatment centers, which has thus far been limited by the number of robust clinical studies that demonstrate cost-effectiveness for the prevention and treatment of toxicitiesCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQnão tem2018/02233-6; 2018/23479-