Comparação da ocorrência de complicações tromboembólicas e hemorrágicas em pacientes portadores de prótese valvares cardíacas mecânicas com um e dois folhetos na posição mitral

Introdução: Pacientes portadores de próteses valvares cardíacas mecânicas devem medicados continuamente com anticoagulantes orais para evitar acidentes tromboembólicos. Estes pacientes são avaliados continuamente para o controle da anticoagulação oral. Objetivo: Comparar a ocorrência de complicações tromboembólicas e hemorrágicas em portadores de próteses valvares cardíacas mecânicas de um (mono) e de dois (bi) folhetos na posição mitral em terapêutica anticoagulante. Métodos: Foram estudados, no intervalo de 10 anos, 117 pacientes portadores de prótese na posição mitral, sendo 48 com próteses de folheto único e 69 de folheto duplo. Avaliou-se a ocorrência de complicações tromboembólicas e hemorrágicas de grau maior e menor de acordo com a gravidade. Os resultados estão apresentados sob forma de estudo atuarial e de frequência linearizada de ocorrência de eventos. Resultados: As curvas atuariais mostraram que, ao longo do tempo, os pacientes portadores de próteses valvares monofolheto estiveram menos livres de complicações tromboembólicas que os pacientes com próteses bifolheto, enquanto que, estes últimos (bifolheto) estiveram menos livres de acidentes hemorrágicos. As frequências linearizadas de ocorrência para tromboembolismo foram maiores nos pacientes com próteses monofolheto. Nos episódios hemorrágicos as taxas foram maiores para os portadores de próteses bifolheto. Conclusão: Os portadores de próteses valvares cardíacas monofolheto mostraram-se mais propensos à ocorrência de acidentes tromboembólicos graves em relação aos com próteses bi folheto. Os pacientes com prótese bifolheto apresentaram maior sangramento que os pacientes com prótese monofolheto, no entanto, esta diferença se restringiu aos sangramentos de pouca gravidade.

A system for environmental monitoring of hydroelectric reservoirs in Brazil

Environmental monitoring of aquatic systems is an important tool to support policy makers and environmental managers' decisions. Long-term, continuous collection of environmental data is fundamental to the understanding of an aquatic system. This paper aims to present the integrated system for environmental monitoring (SIMA), a long-term temporal series system with a web-based archive for limnological and meteorological data. The following environmental parameters are measured by SIMA: chlorophyll-a (µgL-1), water surface temperature (ºC), water column temperature by a thermistor string (ºC), turbidity (NTU), pH, dissolved oxygen concentration (mg L-1), electric conductivity (µS cm-1), wind speed (ms-1) and direction (º), relative humidity (%), shortwave radiation (Wm-2) and barometric pressure (hPa). The data were collected in a preprogrammed time interval (1 hour) and were transmitted by satellite in quasi-real time for any user within 2500 km of the acquisition point. So far, 11 hydroelectric reservoirs are being monitored with the SIMA buoy. Basic statistics (mean and standard deviation) and an example of the temporal series of some parameters were displayed at a database with web access. However, sensor and satellite problems occurred due to the high data acquisition frequency. Sensors problems occurred due to the environmental characteristics of each aquatic system. Water quality sensors rapidly degrade in acidic waters, rendering the collected data invalid. Data is also rendered invalid when sensors become infested with periphyton. Problems occur with the satellites' reception of system data when satellites pass over the buoy antenna. However, the data transfer at some inland locations was not completed due to the satellite constellation position. Nevertheless, the integrated system of water quality and meteorological parameters is an important tool in understanding the aquatic system dynamic. It can also be used to create hydrodynamics models of the aquatic system to allow for the study of meteorological implications to the water body.

Desenvolvimento de uma ferramenta de otimização para avaliar a expansão da transmissão de energia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Modelo matemático para o controle ótimo de Volt/VAr em sistemas de distribuição de energia elétrica trifásicos

Pós-graduação em Engenharia Elétrica - FEIS

Análise de Tópicos Relevantes em Programação Linear e Aplicações no Ensino de Engenharia

Pós-graduação em Engenharia Elétrica - FEIS

Adsorção-fotodegradação do herbicida paraquate em água pela argila Na-Bentonita e por novos materiais TiO2-Bentonita, TiO2/ZnOBentonita, Al/Fe-Bentonita e Al/Fe.Cu-Bentonita

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Massive spin-2 theories in arbitrary D>= 3 dimensions

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Developing an optimization tool for evaluating the transmission system expansion

The transmission system is responsible for connecting the power generators to consumers safely and reliably, its constant expansion is necessary to transport increasing amounts of electricity. In order to help the power systems engineers, an optimization tool for optimize the expansion of the transmission system was developed using the modeling method of the linearized load flow and genetic. This tool was designed to simulate the impact of different scenarios on the cost of transmission expansion. The proposed tool was used to simulate the effects of the presence of distributed generation in the expansion of a fictitious transmission system, where it was found a clear downward trend in investment required for the expansion of the transmission system taking account of increasing levels of distributed generation.

Construction of R4 terms in N = 2 D = 8 superspace

Using linearized superfields, R4 terms in the Type II superstring effective action compactified on T2 are constructed as integrals in N = 2 D = 8 superspace. The structure of these superspace integrals allows a simple proof of the R4 non-renormalization theorems which were first conjectured by Green and Gutperle. © 1998 Elsevier Science B.V.

Cassava root husks as a sorbent material for the uptake and pre-concentration of cadmium(II) from aqueous media

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cordas cósmicas e gravitação planar de ordem superior

The possibility of generalizing gravity in 2+1 dimensions to include higher-derivative terms, thereby allowing for a dynamical theory, opens up a variety of new interesting questions. This is in great contrast with pure Einstein gravity which is a generally covariant theory that has no degrees of freedom - a peculiarity that, in a sense, renders it a little insipid and odorless. The research on gravity of particles moving in a plane, that is, living in flatland, within the context of higher-derivative gravity, leads to novel and interesting effects. For instance, the generation of gravity, antigravity, and gravitational shielding by the interaction of massive scalar bosons via a graviton exchange. In addition, the gravitational deffection angle of a photon, unlike that of Einstein gravity, is dependent of the impact parameter. On the other hand, the great drawback to using linearized general relativity for describing a gravitating string is that this description leads to some unphysical results such as: (i) lack of a gravity force in the nonrelativistic limit; (ii) gravitational deffection independent of the impact parameter. Interesting enough, the effective cure for these pathologies is the replacement of linearized gravity by linearized higher-derivative gravity. We address these issues here