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Este trabalho tem como tema central o planejamento da manutenção em transformadores de potência em subestações. Os transformadores de potência têm uma grande importância nos sistemas de transmissão e distribuição de energia elétrica. Além de serem essenciais para efetuar a transformação entre os diferentes níveis de tensão elétrica ao longo do sistema desde a geração até o consumo, o valor destes equipamentos representa uma parcela considerável do investimento das concessionárias no sistema. Uma falha em um transformador de potência pode comprometer o fornecimento de energia elétrica para uma região inteira da cidade, o que representa falta de faturamento e multas para a concessionária, além dos próprios custos de reparação do equipamento que falhou. Nesta dissertação é abordada uma das principais técnicas utilizadas para diagnósticos de transformadores de potência: a Análise de Gases Dissolvidos (AGD), bem como a utilização da lógica Fuzzy em conjunto com os diferentes métodos de análise desta técnica. O diferencial deste trabalho está no desenvolvimento de uma ferramenta computacional que permite a visualização gráfica da evolução do diagnóstico de cada equipamento ao longo do tempo e fornece um resultado final através de um fluxograma que considera os diagnósticos de todas as técnicas tradicionais abordadas com a aplicação da lógica Fuzzy. O resultado obtido é o desenvolvimento de um software que implementa a metodologia proposta e apresenta, de forma gráfica, os diagnósticos de cada equipamento presente no banco de dados da empresa. O software permite a análise do atual estado operacional do equipamento e a evolução deste diagnóstico ao longo do tempo, subsidiando a tomada de decisão do profissional da manutenção quanto às manutenções no equipamento. This work have its main theme on the maintenance in Power Transformers in energy substations. Power Transformers have great importance in power transmission and distribution systems. In addition to being essential to perform the transformation between diferent levels of electrical voltage from generation to consumption, the cost of these equipments represents a considerable part of the investment in the system. A failure in a transformer can compromise the supply of electricity to an entire region of the city, which represents a lack of billing and fines to the power distribution company, as well as the repair costs of the equipment that failed. In this dissertation one of the main techniques used to diagnose power transformers using the Dissolved Gas Analysis (DGA) are discussed, as well as the use of Fuzzy Logic in conjunction with the diferente analysis techniques. The differential of this work is the development of a computational tool that allows the grafical visualization of diagnosis evolution for each equipment over time and provides a final result by a flowchart that considers all diagnosis of the traditional techniques approached with application of Fuzzy Logic. The result obtained is the development of a software that implements the proposed methodology and graphically presents the diagnostics of each equipment present in the company’s database. The software allows the analysis of the current operational state of the equipment and his evolution over time, subsidizing the decision of the maintenance professional regarding maintenance in the equipment. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES

Monocytes are circulating, short-lived mononuclear phagocytes, which in mice and man comprise two main subpopulations. Murine Ly6C(+) monocytes display developmental plasticity and are recruited to complement tissue-resident macrophages and dendritic cells on demand. Murine vascular Ly6C(-) monocytes patrol the endothelium, act as scavengers, and support vessel wall repair. Here we characterized population and single cell transcriptomes, as well as enhancer and promoter landscapes of the murine monocyte compartment. Single cell RNA-seq and transplantation experiments confirmed homeostatic default differentiation of Ly6C(+) into Ly6C(-) monocytes. The main two subsets were homogeneous, but linked by a more heterogeneous differentiation intermediate. We show that monocyte differentiation occurred through de novo enhancer establishment and activation of pre-established (poised) enhancers. Generation of Ly6C(-) monocytes involved induction of the transcription factor C/EBP{beta} and C/EBP{beta}-deficient mice lacked Ly6C(-) monocytes. Mechanistically, C/EBP{beta} bound the Nr4a1 promoter and controlled expression of this established monocyte survival factor.

Background and Purpose Whether intravenous thrombolysis adds a further benefit when given before endovascular thrombectomy (EVT) is unknown. Furthermore, intravenous thrombolysis delays time to groin puncture, mainly among drip and ship patients. Methods Using region-wide registry data, we selected cases that received direct EVT or combined intravenous thrombolysis+EVT for anterior circulation strokes between January 2011 and October 2015. Treatment effect was estimated by stratification on a propensity score. The average odds ratios for the association of treatment with good outcome and death at 3 months and symptomatic bleedings at 24 hours were calculated with the Mantel-Haenszel test statistic. Results We included 599 direct EVT patients and 567 patients with combined treatment. Stratification through propensity score achieved balance of baseline characteristics across treatment groups. There was no association between treatment modality and good outcome (odds ratio, 0.97; 95% confidence interval, 0.74-1.27), death (odds ratio, 1.07; 95% confidence interval, 0.74-1.54), or symptomatic bleedings (odds ratio, 0.56; 95% confidence interval, 0.25-1.27). Conclusions This observational study suggests that outcomes after direct EVT or combined intravenous thrombolysis+EVT are not different. If confirmed by a randomized controlled trial, it may have a significant impact on organization of stroke systems of care.

Introducción y Objetivos: la modificación de conductas no saludables es fundamental para tratar la obesidad. El objetivo de este estudio fue evaluar los efectos de un programa basado en dieta, ejercicio y apoyo psicológico en la modificación conductual de pacientes con sobrepeso y obesidad tratados en Atención Primaria. Métodos: 60 pacientes con sobrepeso grado II y obesidad grado I-II fueron incluidos en este ensayo piloto. Edad entre 18-50 años. Los pacientes recibieron un programa que combinaba educación nutricional, actividad física y apoyo psicológico. Formato grupal, periodicidad quincenal. Los principales resultados medidos al inicio y 6 meses fueron parámetros antropométricos (índice de masa corporal, porcentaje de masa grasa, perímetro cintura) y de estilos de vida usando el Cuestionario para la valoración de hábitos de vida relacionados con el sobrepeso y la obesidad. Consta de 5 dimensiones: contenido calórico de la dieta (CC), alimentación saludable (AS), ejercicio físico (EF), comer por bienestar psicológico (BP) y consumo de alcohol (CA). La mayor puntuación indica mejores hábitos para CC, AS y EF y peores para BP y CA. Resultados: al final de la intervención mejoraron las escalas CC (2,60± 0,5 vs 3,49± 0,7, p

Introducción y Objetivos: la modificación de conductas no saludables es fundamental para tratar la obesidad. El objetivo de este estudio fue evaluar los efectos de un programa basado en dieta, ejercicio y apoyo psicológico en la modificación conductual de pacientes con sobrepeso y obesidad tratados en Atención Primaria. Métodos: 60 pacientes con sobrepeso grado II y obesidad grado I-II fueron incluidos en este ensayo piloto. Edad entre 18-50 años. Los pacientes recibieron un programa que combinaba educación nutricional, actividad física y apoyo psicológico. Formato grupal, periodicidad quincenal. Los principales resultados medidos al inicio y 6 meses fueron parámetros antropométricos (índice de masa corporal, porcentaje de masa grasa, perímetro cintura) y de estilos de vida usando el Cuestionario para la valoración de hábitos de vida relacionados con el sobrepeso y la obesidad. Consta de 5 dimensiones: contenido calórico de la dieta (CC), alimentación saludable (AS), ejercicio físico (EF), comer por bienestar psicológico (BP) y consumo de alcohol (CA). La mayor puntuación indica mejores hábitos para CC, AS y EF y peores para BP y CA. Resultados: al final de la intervención mejoraron las escalas CC (2,60± 0,5 vs 3,49± 0,7, p

"We discuss several steps in the process of simulating and visualizing large and varied crowds in real time for consumer-level computers and graphic cards (GPUs). Animating varied crowds using a diversity of models and animations (assets) is complex and costly. One has to use models that are expensive if bought, take a long time to model, and consume too much memory and computing resources. We discuss methods for simulating, generating, animating and rendering crowds of varied aspect and a diversity of behaviors. Efficient simulations run in low cost systems because we use the power of modern programmable GPUs. One can apply similar technology using GPU clusters and HPC for large scale problems. Such systems scale up almost linearly by using multiple nodes. One must combine parallel simulation and parallel rendering in the cluster with interaction and final rendering in lighter clients. However, in view of the latest developments such as the new family of mobile multicore chipsets and GPU-based cloud gaming platforms, the pieces are almost there for this kind of architecture to work."

BACKGROUND AND PURPOSE: Giant/large peripheral cerebral aneurysms beyond the circle of Willis and middle cerebral artery (MCA) bifurcation are rare lesions, their etiopathogenesis is not completely elucidated, and their treatment is often difficult. We reviewed the etiopathologic findings available in the literature and report the results and long-term follow-up in 10 patients with a giant/large peripheral aneurysm treated by parent artery occlusion. METHODS: Four aneurysms were on the MCA, 2 on the anterior cerebral artery, and 4 on the posterior cerebral artery (PCA). Two patients presented with bleeding. An occlusion test was performed in 7 patients. Occlusion of the parent artery was performed by using coils in 8 patients; and liquid coils and glue, in 2. Imaging follow-up was available from 1.5 to 4.5 years; and clinical outcome, from 1.5 to 7 years. RESULTS: All aneurysms were excluded. One patient developed a partial homonymous hemianopsia after PCA occlusion. A transient deficit was observed in 2 other patients. In the partially thrombosed aneurysms, follow-up imaging showed shrinkage of the thrombosed compartment of the aneurysm and disappearance of the mass effect. No patient experienced progression of symptoms and/or bleeding during the follow-up period. At long-term follow-up, 6 patients presented with a modified Rankin Scale score of 0; 3, with score of 1; and 1, with score of 2. CONCLUSION: The endovascular occlusion of the parent artery appears a relatively safe and efficacious technique in the treatment of these lesions. Long-term follow-up studies confirm persistent exclusion of the aneurysm and good clinical tolerance to the vessel occlusion.

Neste trabalho apresentamos uma nova abordagem para a ordenação de documentos a partir do modelo de espaço vetorial. A sua originalidade apresenta-se em dois pontos principais: Primeiro, padrões de correlação entre os termos são levados em consideração e processados de forma eficiente. Segundo, a ponderação dos termos é baseada em uma técnica de mineração de dados chamada de regras de associação. A partir desses pontos definimos um novo mecanismo de ordenação chamado modelo de espaço vetorial baseado em conjuntos. Os componentes desse modelo deixam de ser os termos, e passam a ser os conjuntos de termos. Os conjuntos de termos capturam a intuição que termos semanticamente relacionados aparecem próximos em um documento. Esses conjuntos podem ser eficientemente gerados limitando sua computação a pequenos trechos de texto. Uma vez computados os conjuntos de termos, a função de ordenação é calculada a partir da freqüência de um conjunto no documento e sua raridade na coleção. Nossa abordagem provê uma forma simples, efetiva, eficiente e parametrizada para o processamento de consultas disjuntivas, conjuntivas, por frases, além de ser usada para a estruturação automática de consultas. Todas as abordagens conhecidas que levam em consideração a correlação entre os termos foram projetadas somente para o processamento de consultas disjuntivas. Resultados experimentais mostram que o nosso modelo aumenta a precisão média para todas as coleções e tipos de consultas avaliados, mantendo o custo computacional adicional aceitável. Para a coleção TREC-8 de 2 gigabytes, a utilização do nosso modelo implica em um ganho de precisão média de 14.7% e 16.4% para consultas disjuntivas e conjuntivas, respectivamente, em relação ao modelo de espaço vetorial padrão. Esses ganhos aumentam para 24.9% e 30.0%, respectivamente, quando a informação de proximidade é levada em consideração. Os tempos de processamento das consultassão maiores, mas continuam comparáveis com os tempos obtidos para o modelo de espaço vetorial (o crescimento no tempo médio de processamento varia de 30% a 300%). Os resultados experimentais também mostram o sucesso do nosso modelo para a estruturação automática de consultas. Por exemplo, utilizando a TREC-8, nosso modelo gera ganhos de precisão média de aproximadamente 28\% em comparação com o mecanismo de ordenação baseado na fórmula de ponderação BM25. Nossos resultados sugerem que a fórmula de ordenação do modelo de espaço vetorial baseado em conjuntos é bastante efetiva e computacionalmente viável para coleções genéricas. This work presents a new approach for ranking documents in the vector space model. Thenovelty lies in two fronts. First, patterns of term co-occurrence are taken into account and are processed ef_ciently. Second, term weights are generated using a data mining technique called association rules. This leads to a new ranking mechanism called the set-based vector model. The components of our model are no longer index terms but index termsets, where a termset is a set of index terms. Termsets capture the intuition that semantically related terms appear close to each other in a document. They can be ef_ciently obtained by limiting the computation to small passages of text. Once termsets have been computed, the ranking is calculated as a function of the termset frequency in the document and its scarcity in the document collection. The application of our approach provides a simple, effective, ef_cient and parameterized way to process disjunctive, conjunctive, phrase queries, and automatically structured complex queries. All known approaches that account for correlation among index terms were initially designed for processing only disjunctive queries. Experimental results show that the set-based vector model improves average precision for all collections and query types evaluated, while keeping computational costs small. For the 2 gigabyte TREC-8 collection, the set-based vector model leads to a gain in average precision _gures of 14.7% and 16.4% for disjunctive and conjunctive queries, respectively, with respect to the standard vector space model. These gains increase to 24.9% and 30.0%, respectively, when proximity information is taken into account. Query processing times are larger but, on average, still comparable to those obtained with the standard vector model (increases in processing time varied from 30% to 300%). The experimental results also show that the set-based model can be successfully used for automatically structuring queries. For instance, using the TREC-8 test collection, our technique led to gains in average precision of roughly 28% with regard to a BM25 ranking formula. Our results suggest that the set-based vector model provides a correlation-based ranking formula that is effective with general collections and computationally practical.

The incidence of hypothyroidism is higher among children with Down syndrome than among children in the general population. The frequency of hypothyroidism is higher in the areas of endemic goiter than in other areas. The aim of this paper was to study the concentrations of TSH and FT4 in children with Down syndrome residents of Mérida, a region of Venezuelan Andes. At the Centro de Estudio y Prevención del Retardo Mental y Alteraciones en el Desarrollo (CEPREMAD), the thyroid function was studied in 48 children (1 month to 6 years old), who had Down syndrome, and in 123 healthy children of similar ages. All the children were referred to the Center for thyroid function evaluation. Two (4.2%) of the 48 children with Down syndrome had congenital hypothyroidism and 22 (45.8%) had subclinical hypothyroidism (high concentration of thyrotropin-TSH). Among the control children, only 14% had elevated levels of TSH. There were no differences in relation to the gender. In conclusion in children with Down syndrome, the frequency of high concentrations of TSH was three times higher than the frequency among the healthy children. The frequency of hypothyroidism was similar to that found in areas without endemic goiter.

Dural arteriovenous fistulas (dAVFs) can cause cerebral venous hypertension (VHT). The most common mechanism is due to the fact that some dAVFs can drain retrogradelly in cortical (better defined as leptomeningeal) veins (directly or after drainage in a dural sinus) causing venous engorgement and consequently an impairment of the cerebral venous drainage. However, more rarely, dAVFs without a cortical venous drainage can also be responsible for VHT probably due to dAVF shunts causing insufficient antegrade cerebral venous drainage. In addition, dAVFs are often associated with stenosis and/or thrombosis of dural sinus(es) which can worsen the VHT. Raised pressure within the superior sagittal sinus causes impeded cerebrospinal reabsorption in the arachnoid villi allowing increased intracranial pressure. The venous engorgement in the cortical veins can cause a venous congestive encephalopathy analogous to the venous congestive myelopathy of the spinal dural AVFs. Clinically VHT can cause not only symptoms related to increased intracranial pressure but also seizures, neurological deficits, impairment of the cognitive functions and dementia. An important aspect is the risk of hemorrhage in dAVFs with a leptomeningeal venous drainage leading to VHT. Although the term VHT sensu strictu should be used if venous pressure measurements are performed, angiographic criteria for VHT such as delayed circulation time, venous engorgement and abnormal visualization of the cerebral veins are well established. The purpose of our study was to evaluate the angiographic signs of VHT in patients with dAVF and to study the course of the VHT and of the clinical signs of increased intracranial pressure before and after dAVF endovascular treatment. A retrospective chart analysis of 22 patients (13 males, 9 females) ranging in age from 20 to 87 years (mean: 53 ys.) with a dAVF associated with angiographic signs of VHT was performed. Ten dAVFs were located on the transverse/sigmoid sinus(es), 6 on the superior sagittal sinus, 3 on the petro-tentorial incisura, 1 on the inferior petrosal sinus, 1 on the anterior ethmoidal region and 1 on the Galen vein region. All dAVFs had a retrograde leptomeningeal venous drainage. Stenosis or thrombosis of the dural AVF sinus was observed in 17 cases and stenosis or thrombosis of another sinus(es) and/or of the jugular vein in 8 cases. In 11 patients, the angiographic signs of VHT were global affecting the entire cerebral venous drainage and, in the other 11 patients, the VHT was focal. The VHT caused clinical symptoms of increased intracranial pressure in 18 patients. Other clinical findings included: bruit (11 cases), seizures (3 cases), vertigo (3 cases), visual deficits (2 cases) and impairment of cognitive functions (4 cases). Three patients presented hemorrhage (one parenchymal hematoma, one hemorrhagic infarction and one subarachnoid hemorrhage). The 4 patients without clinical symptoms of increased intracranial pressure presented only bruit in 2 cases, bruit and vertigo in 1 case, bruit and hemorrhagic infarction in another one. The dAVFs were treated by endovascular therapy (arterial approach: 3 cases, venous approach: 6 cases and both arterial and venous approach: 13 cases). Endovascular sessions ranged from 1 to 7 (mean: 2.8) for each patient. After the endovascular treatment, in 12 patients with complete occlusion of the dAVF, the disappearance of angiographic signs of VHT and clinical cure were observed. In 8 patients with partial occlusion of the dAVF, the disappearance of angiographic signs of VHT and clinical cure were observed in 4 cases (almost complete dAVF occlusion in 2 cases); in the other 4 cases, only reduction the angiographic signs of VHT and clinical improvement were obtained. In all 16 patients who were clinically cured angiographic signs of VHT disappeared despite the persistence of dAVF shunts as observed in 4 cases. (ABSTRACT TRUNCATED)

Se presenta una metodología objetiva para realizar la zonificación agroclimática de la región de La Mojana, usando el sistema de información geográfica ARC/INFO y empleando la combinación de técnicas de agrupamiento estadístico/matemáticas, conocidas como análisis de Cluster y de componentes principales, teniendo en cuenta la variación espacio-temporal de los elementos climáticos y espaciales del suelo y la vegetación. Este estudio se realizó sobre la Región de La Mojana, en Colombia, para lo cual se empleo la información de 30 estaciones pluviométricas, 1 pluviográfica y 13 estaciones climáticas. Toda la información se desplegó en el sistema de información geográfica ARC/INFO, con celdas de 250 X 250 m2 (6.25 ha), y se interpoló mediante el algoritmo denominado distancia inversa ponderada propuesto por Watson y Philip en 1985. La zonificación se efectuó teniendo en cuenta los excesos de precipitación que se obtienen del balance hídrico y que se producen durante el periodo de lluvias. Estos excesos se presentaron en las décadas de 12 a 33. Con base en los mapas se creó una matriz geográfica en donde cada mapa representa la variación espacial de los excesos de precipitación en una década. A esta matriz se aplicó el método de los componentes principales escogiéndose los que representaban la mayor variabilidad. Después, se aplicó el análisis de Cluster usando el método de isocluster, produciéndose una zonificación final que se presenta en un mapa con su leyenda correspondiente.