Evuloção cognitiva e funcional de pacientes pós-acidente vascular cerebral - AVC

PURPOSE: Stroke is a high-incidence cerebrovascular disease with elevated morbidity that results in impairments such as functional disabilities. This study aimed to investigate the functional evolution of individuals in the first six months post-stroke. METHOD: Longitudinal study with 42 stroke patients. The functional independence measure (FIM) and The National Institutes of Health Stroke Scale (NIHSS) were used by multidisciplinary staff 3 times in each participant; the first application was at admission to rehabilitation and the others three and six months later. RESULTS: Sample predominantly female (57%), married (52%), mean age 65.26 ±10.72 years, elementary schooling level (43%), ischemic stroke (91%), and right cerebral hemisphere (74%). Motor FIM scores and NIHSS scale showed improvement in the 3 evaluations, with significant p-value (<0.001). There was a strong relation between motor FIM evolution and NIHSS evolution (r = - 0.69 p-value< 0.001). CONCLUSIONS: It was observed that functional evolution at 6 months post-stroke was significant and the smaller the evolution of clinical impairment in these patients, the larger the evolution of their functional independence. The study is important because it allows a more appropriate therapeutic planning according with functional evolution in stroke rehabilitation

Contribuições a técnicas de agrupamento e visualização de dados multivariados utilizando mapas auto-organizáveis

Self-organizing maps (SOM) are artificial neural networks widely used in the data mining field, mainly because they constitute a dimensionality reduction technique given the fixed grid of neurons associated with the network. In order to properly the partition and visualize the SOM network, the various methods available in the literature must be applied in a post-processing stage, that consists of inferring, through its neurons, relevant characteristics of the data set. In general, such processing applied to the network neurons, instead of the entire database, reduces the computational costs due to vector quantization. This work proposes a post-processing of the SOM neurons in the input and output spaces, combining visualization techniques with algorithms based on gravitational forces and the search for the shortest path with the greatest reward. Such methods take into account the connection strength between neighbouring neurons and characteristics of pattern density and distances among neurons, both associated with the position that the neurons occupy in the data space after training the network. Thus, the goal consists of defining more clearly the arrangement of the clusters present in the data. Experiments were carried out so as to evaluate the proposed methods using various artificially generated data sets, as well as real world data sets. The results obtained were compared with those from a number of well-known methods existent in the literature

Obtenção de compósitos cerâmicos baseados em Al2O3/TiC através dos precursores poliméricos

The obtaining of ceramic materials from polymeric precursors is subject of numerous studies due to lower energy costs compared to conventional processing. The aim of this study is to investigate and improve the mechanism for obtaining ceramic matrix composite (CMC) based on SiOC/Al2O3/TiC by pyrolysis of polysiloxane in the presence of an active filler and inert filler in the pyrolysis temperature lower than the usually adopted for this technique, with greater strength. It also investigates the influence of pyrolysis temperature, the content of Alas active filler, the presence of infiltrating agents (Al, glass and polymer) after pyrolysis, temperature and infiltration time on some physical and mechanical properties. Alumina is used as inert filler and Al and Ti as active filler in the pyrolysis. Aluminum, glass and polysiloxane are used as agents infiltrating the post-pyrolysis. The results are analyzed with respect to porosity and bulk density by the Archimedes method, the presence of crystalline phases by X-ray diffraction (XRD) and microstructure by scanning electron microscopy (SEM). The ceramic pyrolyzed between 850 °C 1400 °C contain porosity 15% to 33%, density 2.34 g/cm3 and flexural strength at 4 points from 30 to 42 MPa. The microstructure features are porous, with an array of Al2O3 reinforced by TiC particles and AlTi3. The infiltration post-pyrolysis reveals decrease in porosity and increase density and strength. The composites have potential applications where thermal stability is the main requirement

Elaboração e avaliação de indicadores comportamentais de aderência ao tratamento hemodialítico

Introduction: This work intents to characterize behavioral indicators of tack to the hemodialysis treatment in a sample of carrying patients of chronic kidney failure (CKF) in the great Natal/RN. The therapeutical adherence represents the agreement degree between the patient behavior and the health team lapsings. The CKF is the gradual and irreversible loss of the renal function, being the hemodialysis treatment an important alternative to assist or to substitute the kidneys. Method: The sample consisted in 80 chronic kidney patients in hemodialysis treatment in two located clinical centers in the region of the great Natal, RN. It was used as instruments (a) a protocol of clinical data collection, (b) the Millon Index of Personality Styles (MIPS) and (c) a script of halfstructuralized interview. Results: The results show a balance between the genders (51% of female and 48.8% of the male sex), average age and equal average time of dialysis respectively to the 43,4 years (±13,25 years) and 22,04 years (±4,24 years). The marital status of half of the sample is married, predominating basic education (43.6%) and a familiar income until a minimum wage (43.8%). It had been defined six physicianlaboratorial indicators to evaluate the therapeutical adherence, further the use of the evaluation of the health team and the patient themselves. Thus, there was an average adherence around 55.97% of the sample ±18.37%). However only between selfassessment of the patients about the adherence and the assessment made by blood pressure post-dialysis indicated a significant association (p=0,029, qui-square test). On the other hand, there was a significant association (p <0.05, chi-square test) among the criteria for treatment adherence and issues investigated in the interview - the perception on the quality of the health services provided to patients, the difficulties following the prescribed diet, the characterization of the days between dialysis sessions and the perception of patients about the dialysis sessions. It was also noted a significant association (p <0.05, Levene test) between adherence to therapy and scales that constitute the MIPS. The health team characterized the patients more adherent behavior as an attitude of acceptance of the treatment, looking actively for their implementation, for more information and knowledge, and establishing a positive communication with the team and with other patients. Similar results were confirmed by the MIPS evaluation. According to that assessment the more compliant patients adopt a more optimistic attitude, trying to act or adapt themselves to their environment, processing cognitively both concrete and objective information, such as more speculative and symbolic information. In addition they establish a gregarious, cooperative, submissive and flexibly pattern of interpersonal relationships to social demands. These characteristics managed to explain 55.7% of the adherence variation according the health team and 23.3% of the variation according the CaxP laboratory indicator. Conclusions: The MIPS shown to be able to identify the most and least adherent to therapy patients. The use of different adherence indicators is important for an evaluation covering the different facets of this process. The adhesion levels are observed within registered by the relevant literature. There is need for further studies with a larger sample to deepen the data findings in this work

Formal verification of PLC programs using the B Method

PLCs (acronym for Programmable Logic Controllers) perform control operations, receiving information from the environment, processing it and modifying this same environment according to the results produced. They are commonly used in industry in several applications, from mass transport to petroleum industry. As the complexity of these applications increase, and as various are safety critical, a necessity for ensuring that they are reliable arouses. Testing and simulation are the de-facto methods used in the industry to do so, but they can leave flaws undiscovered. Formal methods can provide more confidence in an application s safety, once they permit their mathematical verification. We make use of the B Method, which has been successfully applied in the formal verification of industrial systems, is supported by several tools and can handle decomposition, refinement, and verification of correctness according to the specification. The method we developed and present in this work automatically generates B models from PLC programs and verify them in terms of safety constraints, manually derived from the system requirements. The scope of our method is the PLC programming languages presented in the IEC 61131-3 standard, although we are also able to verify programs not fully compliant with the standard. Our approach aims to ease the integration of formal methods in the industry through the abbreviation of the effort to perform formal verification in PLCs

Processing of highly porous titanium parts by metal injection moulding in combination with innovative plasma treatment

A combinação da Moldagem por Injeção de pós Metálicos (Metal Injection Moulding MIM) e o Método do Retentor Espacial (Space Holder Method - SHM) é uma técnica promissora para fabricação de peças porosas de titânio com porosidade bem definida como implantes biomédicos, uma vez que permite um alto grau de automatização e redução dos custos de produção em larga escala quando comparado a técnica tradicional (SHM e usinagem a verde). Contudo a aplicação desta técnica é limitada pelo fato que há o fechamento parcial da porosidade na superfície das amostras, levando ao deterioramento da fixação do implante ao osso. E além disso, até o presente momento não foi possível atingir condições de processamento estáveis quando a quantidade de retentor espacial excede 50 vol. %. Entretanto, a literatura descreve que a melhor faixa de porosidade para implantes de titânio para coluna vertebral está entre 60 - 65 vol. %. Portanto, no presente estudo, duas abordagens foram conduzidas visando a produção de amostras altamente porosas através da combinação de MIM e SHM com o valor constante de retentor espacial de 70 vol. % e uma porosidade aberta na superfície. Na primeira abordagem, a quantidade ótima de retentor espacial foi investigada, para tal foram melhorados a homogeneização do feedstock e os parâmetros de processo com o propósito de permitir a injeção do feedstock. Na segunda abordagem, tratamento por plasma foi aplicado nas amostras antes da etapa final de sinterização. Ambas rotas resultaram na melhoria da estabilidade dimensional das amostras durante a extração térmica do ligante e sinterização, permitindo a sinterização de amostras de titânio altamente porosas sem deformação da estrutura.