Vestibular rehabilitation with biofeedback in patients with central imbalance

Central Nervous System disorders may cause important functional unbalance in the maintenance of balance and posture. There is no effective rehabilitation for these symptoms until now. Objective: The aim of this paper is to evaluate the use of tongue electrotactile stimulation on patients with central imbalance using BrainPort. Materials and Methods: This is a prospective case series study. We evaluated 8 patients with central imbalance, 6 men and 2 women, with mean age of 67.75 years. The patients were submitted to Computed Dynamic Posturography (CDP) and then received 18 sessions of electrotactile stimulation by BrainPort (R) device for 20 minutes, twice a day. Then they were submitted to a new CDP test and to a self-perception scale to assess symptom remission, partial improvement and no improvement at all. Results: 75% of the patients reported being more stable. There was no improvement in the balance control of the mass center in these patients. Conclusion: The patients were able to use the electrotactile stimulus to improve their balance control.

Clastic cells: Mineralized tissue resorption in health and disease

Clastic cells are responsible for mineralized tissue resorption. Bone resorbing cells are called osteo-clasts; however, they are able to resorb mineralized dental tissues or calcified cartilage and then they are called odontoclasts and chondroclasts, respectively. They derive from mononuclear precursors of the monocyte-macrophage lineage from hemopoietic tissue, reach target mineralized tissues and degrade them under many different physiologic or pathologic stimuli. Clastic cells play a key role in calcium homeostasis, and participate in skeletal growth, tooth movement, and other physiological and pathological events. They interact tightly with forming cells in bone and dental hard tissues; their unbalance may result in disturbed resorptive activity thus, causing local or systemic diseases. (C) 2008 Elsevier Ltd. All rights reserved.

A qualidade do gasto p??blico e a avalia????o das pol??ticas sociais: o or??amento do Minist??rio do Trabalho no per??odo 2000-2006

Nos ??ltimos anos, o debate sobre a melhoria da qualidade do gasto p??blico tem ganhado espa??o crescente. As quest??es mais gerais do tema s??o relevantes, mas n??o substituem o exame espec??fico dos gastos sociais dos diversos minist??rios ??? raz??o pela qual a avalia????o das pol??ticas p??blicas ?? instrumento fundamental para melhoria do gasto. O trabalho corrente faz uma avalia????o da din??mica or??ament??ria das pol??ticas do Minist??rio do Trabalho e Emprego. Essa an??lise revela um crescente desequil??brio: enquanto o valor destinado ??s pol??ticas passivas de emprego aumentou brutalmente, os valores destinados ??s pol??ticas ativas de emprego ca??ram significativamente. Esse cen??rio ??? oposto ao que seria desej??vel ??? ?? ainda mais preocupante na medida em que as pol??ticas passivas de emprego n??o beneficiam os mais pobres. Neste contexto, o trabalho avalia a possibilidade de que parte dos recursos reservados para pol??ticas passivas seja dirigido ??s pol??ticas ativas de emprego.

Análise da fibrose do tecido adiposo de mulheres submetidas à abdominoplastia e cirurgia bariátrica

A fibrose é um acúmulo demasiado de matriz extracelular, resultante de um desequilíbrio entre a síntese e a degradação dos seus componentes. É associada às alterações metabólicas do tecido adiposo, contudo sua ocorrência nos diferentes depósitos e repercussões clínicas ainda não são totalmente compreendidas. O objetivo deste estudo foi analisar a fibrose no tecido adiposo em relação à presença de obesidade, localização do depósito [tecido adiposo subcutâneo abdominal (TASA) e visceral (TAV)] e sua associação a variáveis clínicas. Amostras de gordura do TASA e TAV foram obtidas de 21 mulheres submetidas à cirurgia bariátrica (IMC>40Kg/m2) e 25 amostras de TASA das submetidas à abdominoplastia (IMC<30Kg/m2). As amostras foram processadas para histologia convencional. O corante picrosirius foi utilizado para avaliação das fibras colágenas totais. As imagens obtidas foram analisadas no ADIPOSOFT®. O percentual de fibrose no TASA e no TAV foi analisado com testes estatísticos não paramétricos, adotando-se um valor de p<0,05. A fibrose no TASA foi maior em mulheres com obesidade (p<0.0006). A fibrose entre os depósitos de TASA e de TAV foi observada apenas em mulheres pardas e negras com obesidade (p<0,012). A fibrose no TASA não foi correlacionada com as variáveis clínicas nas mulheres sem obesidade. No entanto, nas submetidas à cirurgia bariátrica, foram observadas correlações da fibrose no TASA com Índice de Massa Corpórea (IMC), hemoglobina glicada (A1c), LDL e triglicerídeos; e no TAV com porcentagem de perda gordura pré-operatório, % de perda de gordura total, % de massa magra pré, Taxa Metabólica Basal (TBM) e Gasto Energético Basal (GEB). Os parâmetros metabólicos e de perfil antropométrico antes da cirurgia bariátrica foram associados à fibrose no TASA, enquanto os parâmetros após a cirurgia foram associados à fibrose no TAV.

The influence of differente speeds on backpacker's gait kinectics

This study analyzed the influence of different speeds on ground reaction force’s (GRF), impulses and mean vertical force during gait of people submitted to occasional overload (backpack). A force plate was used to record the GRF data of 60 young adult subjects walking in two different cadences: 69 steps/min (slow gait) and 120 steps/min (fast gait). During the slow gait, the impact and propulsive impulses of vertical GRF, propulsive impulse of anterior-posterior GRF, impulse of medial-lateral GRF and duration of stance phase were larger than during the fast gait; the mean vertical force was the only variable that showed larger values during fast gait. Therefore, slow gait may present a larger possibility of blister development and gait unbalance, while the fast gait, even presenting a small impulse, seems to be more harmful to the musculoskeletal system.

Effect of oxidative stress upon absorption of glucose by the human placenta: in vitro studies with BeWo cells

Pregnancy is a dynamic state and the placenta is a temporary organ that, among other important functions, plays a crucial role in the transport of nutrients and metabolites between the mother and the fetus, which is essential for a successful pregnancy. Among these nutrients, glucose is considered a primary source of energy and, therefore, fundamental to insure proper fetus development. Several studies have shown that glucose uptake is dependent on several morphological and biochemical placental conditions. Oxidative stress results from the unbalance between reactive oxygen species (ROS) and antioxidants, in favor of the first. During pregnancy, ROS, and therefore oxidative stress, increase, due to increased tissue oxygenation. Moreover, the relation between ROS and some pathological conditions during pregnancy has been well established. For these reasons, it becomes essential to understand if oxidative stress can compromise the uptake of glucose by the placenta. To make this study possible, a trophoblastic cell line, the BeWo cell line, was used. Experiments regarding glucose uptake, either under normal or oxidative stress conditions, were conducted using tert-butylhydroperoxide (tBOOH) as an oxidative stress inducer, and 3H-2-deoxy-D-glucose (3H-DG) as a glucose analogue. Afterwards, studies regarding the involvement of glucose facilitative transporters (GLUT) and the phosphatidylinositol 3-kinases (PI3K) and protein kinase C (PKC) pathways were conducted, also under normal and oxidative stress conditions. A few antioxidants, endogenous and from diet, were also tested in order to study their possible reversible effect of the oxidative effect of tBOOH upon apical 3H-DG uptake. Finally, transepithelial studies gave interesting insights regarding the apical-to-basolateral transport of 3H-DG. Results showed that 3H-DG uptake, in BeWo cells, is roughly 50% GLUT-mediated and that tBOOH (100 μM; 24h) decreases apical 3H-DG uptake in BeWo cells by about 33%, by reducing both GLUT- (by 28%) and non-GLUT-mediated (by 40%) 3H-DG uptake. Uptake of 3H-DG and the effect of tBOOH upon 3H-DG uptake are not dependent on PKC and PI3K. Moreover, the effect of tBOOH is not associated with a reduction in GLUT1 mRNA levels. Resveratrol, quercetin and epigallocatechin-3-gallate, at 50 μM, reversed, by at least 45%, the effect of tBOOH upon 3H-DG uptake. Transwell studies show that the apical-to-basolateral transepithelial transport of 3H-DG is increased by tBOOH.In conclusion, our results show that tBOOH caused a marked decrease in both GLUT and non-GLUT-mediated apical uptake of 3H-DG by BeWo cells. Given the association of increased oxidative stress levels with several important pregnancy pathologies, and the important role of glucose for fetal development, the results of this study appear very interesting.

Simulação, em software adequado, da sintomatologia vibracional de avarias mecânicas de máquinas rotativas

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica na Área de Manutenção e Produção

Controlo clássico vs. preditivo na regulação de frequência em sistemas de potência

Dissertação para obtenção do grau de Mestre em Engenharia Electrotécnica Ramo Automação e Electrónica Industrial

Effects of early life permethrin exposure on spatial working memory and on monoamine levels in different brain areas of pre-senescent rats

Pesticide exposure during brain development could represent an important risk factor for the onset of neurodegenerative diseases. Previous studies investigated the effect of permethrin (PERM) administered at 34 mg/kg, a dose close to the no observable adverse effect level (NOAEL) from post natal day (PND) 6 to PND 21 in rats. Despite the PERM dose did not elicited overt signs of toxicity (i.e. normal body weight gain curve), it was able to induce striatal neurodegeneration (dopamine and Nurr1 reduction, and lipid peroxidation increase). The present study was designed to characterize the cognitive deficits in the current animal model. When during late adulthood PERM treated rats were tested for spatial working memory performances in a T-maze-rewarded alternation task they took longer to choose for the correct arm in comparison to age matched controls. No differences between groups were found in anxiety-like state, locomotor activity, feeding behavior and spatial orientation task. Our findings showing a selective effect of PERM treatment on the T-maze task point to an involvement of frontal cortico-striatal circuitry rather than to a role for the hippocampus. The predominant disturbances concern the dopamine (DA) depletion in the striatum and, the serotonin (5-HT) and noradrenaline (NE) unbalance together with a hypometabolic state in the medial prefrontal cortex area. In the hippocampus, an increase of NE and a decrease of DA were observed in PERM treated rats as compared to controls. The concentration of the most representative marker for pyrethroid exposure (3-phenoxybenzoic acid) measured in the urine of rodents 12 h after the last treatment was 41.50 µ/L and it was completely eliminated after 96 h.

Diagnóstico de avarias em máquinas rotativas utilizando a análise de órbitas

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica Perfil Manutenção e Produção

Fifth harmonic and sag impact on PMSG wind turbines with a balancing new strategy for capacitor voltages

This paper deals with the computing simulation of the impact on permanent magnet synchronous generator wind turbines due to fifth harmonic content and grid voltage decrease. Power converter topologies considered in the simulations are the two-level and the three-level ones. The three-level converters are limited by unbalance voltages in the DC-link capacitors. In order to lessen this limitation, a new control strategy for the selection of the output voltage vectors is proposed. Controller strategies considered in the simulation are respectively based on proportional integral and fractional-order controllers. Finally, a comparison between the results of the simulations with the two controller strategies is presented in order to show the main advantage of the proposed strategy. (C) 2014 Elsevier Ltd. All rights reserved.

Simulation of rectifier voltage malfunction on OWECS, four-level converter, HVDC light link: Smart grid context tool

This paper presents a model for the simulation of an offshore wind system having a rectifier input voltage malfunction at one phase. The offshore wind system model comprises a variable-speed wind turbine supported on a floating platform, equipped with a permanent magnet synchronous generator using full-power four-level neutral point clamped converter. The link from the offshore floating platform to the onshore electrical grid is done through a light high voltage direct current submarine cable. The drive train is modeled by a three-mass model. Considerations about the smart grid context are offered for the use of the model in such a context. The rectifier voltage malfunction domino effect is presented as a case study to show capabilities of the model. (C) 2015 Elsevier Ltd. All rights reserved.

On performance of distributed model predictive control in power system frequency regulation

This paper describes the implementation of a distributed model predictive approach for automatic generation control. Performance results are discussed by comparing classical techniques (based on integral control) with model predictive control solutions (centralized and distributed) for different operational scenarios with two interconnected networks. These scenarios include variable load levels (ranging from a small to a large unbalance generated power to power consumption ratio) and simultaneously variable distance between the interconnected networks systems. For the two networks the paper also examines the impact of load variation in an island context (a network isolated from each other).

Simulation of OWES with five-Level converter linked to the grid: Harmonic assessment

This paper deals with a computing simulation for an offshore wind energy system taking into account the influence of the marine waves action throughout the floating platform. The wind energy system has a variable-speed turbine equipped with a permanent magnet synchronous generator and a full-power five level converter, injecting energy into the electric grid through a high voltage alternate current link. A reduction on the unbalance of the voltage in the DC-link capacitors of the five-level converter is proposed by a strategic selection of the output voltage vectors. The model for the drive train of the wind energy system is a two mass model, including the dynamics of the floating platform. A case study is presented and the assessment of the quality of the energy injected into the electric grid is discussed.

Role of sirtuin 3 on mitochondrial dynamics in Huntington's disease striatal cells

Dissertação de mestrado em Genética Molecular