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This article presents a study on the tensile properties of knitted fabrics commonly employed in polymeric matrix textile composites. The key mechanical parameters investigated include stress (Pa), strain, Young's modulus (Pa), and work of rupture (J). The knitted fabrics were developed using the Cixing Knitting System software and subsequently manufactured using a double jersey (electronic) flat knitting machine. The primary objective of this research was to explore the impact of various factors on the mechanical behavior of these knitted fabrics. The factors studied were wale and course directions, float stitch density, loop length (cm), and the type of synthetic knitting yarns used (100% polyester and 100% polyamide) along with different combinations of knitting yarns (100% cotton and 67% polyester/33% cotton hybrid). The adopted ASTM D 5034 standard, Response Surface Methodology (RSM), and Analysis of Variance (ANOVA) were employed to evaluate the mechanical performance of these fabric structures. The findings of the study revealed that the statistical adjustment of the data set for stress, strain, Young's modulus, and work of rupture in knitted fabric structures significantly reduced the standard deviations for mechanical responses. This information holds particular significance as it pertains to the frequent use of these knitted fabric structures as reinforcement in textile-reinforced composite materials. Overall, this study sheds light on the mechanical behavior in structures of knitted fabrics used in polymeric matrix composites, providing valuable insights for the design and optimization of advanced textile-based materials.

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O objetivo deste trabalho foi avaliar e verificar a alteração qualitativa e quantitativa do tônus muscular, de membros inferiores de pacientes com seqüelas de lesão medular, por meio de um questionário e de três testes de avaliação (Escala de Ashworth Modificada; Goniometria e Teste de Abdução Brusca e Lenta), realizados antes e após de uma única sessão de hidroterapia. Foram selecionados cinco pacientes da Fundação Selma Reabilitação Física e Social, com lesão acima da décima segunda vértebra torácica, os quais foram submetidos ao protocolo de hidroterapia estabelecido. Aproximadamente 50% dos grupos musculares dos membros inferiores, avaliados pela escala de Ashworth Modificada, apresentaram alterações de espasticidade estatisticamente significantes (flexores e abdutores de quadril; dorsiflexores de tornozelo). Observou-se, também, uma diferença estatisticamente significante nos testes de abdução lenta e brusca de quadril. Na avaliação quantitativa por meio da goniometria, observou-se uma diferença estatística significativa da terapia, de forma unilateral em joelho, para os movimentos de flexão e, em tornozelo, para os movimentos de dorsiflexão. Embora o tamanho da amostra tenha sido pequeno, houve diferença, estatisticamente significativa, nas três avaliações realizadas pós-tratamento, sugerindo que a hidroterapia pode ser benéfica em minimizar a espasticidade, em pacientes portadores de lesão raquimedular acima do décimo segundo segmento torácico.

The purpose of this work was to assess and verify the qualitative and quantitative muscle tone alteration of spinal cord injured people’s lower limbs by using a questionnaire and three assessement tools (Modifyied Ashworth Scale; Goniometric and the fast and slow movements of Abduction Tests), which were performed before and after only one Hydrotherapy session. Five patients with spinal cord injury above the 12th thoracic level (T12) from Fundação Selma had been selected and been submited to the same set protocol. Nearly 50% of lower limbs’ muscle groups assessed by Modifyied Ashworth Scale had shown statistical difference (hip flexors and abductors and ankle dorsoflexors). It was also found statistical difference in the fast and slow movements of Abduction Tests. The goniometric quantitative assessment was found statistical difference in one-sided knee for the flex movement and in both sided ankle dorsoflexors. Although the sample size was small, there was statistical difference suggesting that the hydrotherapy can be beneficial to minimize the spasticity in spinal cord injured above T12.

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OBJECTIVE: Before the use of the ISAAC (International Study of Asthma and Allergies in Childhood) questionnaire in epidemiologic surveys, little could be told about the comparative occurrence of asthma in the world due to differences in employed methods. In Brazil, the ISAAC questionnaire has been used in some urban regions. In this study it was applied in both, urban and rural areas, in order to estimate the prevalence of asthma among schoolchildren living in Montes Claros, Brazil. METHODS: A cross-sectional study was carried out using the ISAAC written questionnaire with four questions added on exposures of interest. The questionnaire was self-applied in 3,770 randomly selected schoolchildren aged 13 and 14 years. RESULTS: The prevalence of "wheezing in the last year" was 15.8%, and "asthma or bronchitis ever" was 23.8% with no statistically significant difference between boys and girls. There were significant differences between girls and boys regarding "wheezing ever" (37.8% and 33.6%), "sleeping disturbed by wheezing" (13.7% and 9.5%), and "nocturnal dry coughing without respiratory infection" (36.6% and 28.7%), respectively. "Wheezing in the last year" was found to be positively associated with "pet contact" (OR=1.27; 95% CI: 1.03-1.56), and "family history of asthma" (OR=1.79; 95% CI: 1.50-2.14), and negatively associated with "rural school" (OR=0.63; 95% CI: 0.44-0.91). But no association was found with sex, age, private/public school, and passive smoking. CONCLUSIONS: The prevalence of asthma in Montes Claros was high and some symptoms were seen mainly among girls. The occurrence of "wheezing in the last year" showed to be associated with family history, contact with pets and urban schools.

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OBJETIVO: Antes do uso do questionário padronizado ISAAC (International Study of Asthma and Allergies in Childhood) em inquéritos epidemiológicos, pouco se conhecia sobre a ocorrência comparativa de asma no mundo, dados os diferentes métodos empregados. No Brasil, outros estudos utilizaram o questionário ISAAC em regiões urbanas. Realizou-se estudo utilizando esse questionário nas zonas urbana e rural com o objetivo de estimar a prevalência de asma em escolares. MÉTODOS: Estudo transversal com o questionário escrito ISAAC, acrescido de perguntas sobre exposições de interesse, auto-aplicado em 3.770 escolares de 13 e 14 anos de idade do município de Montes Claros (MG) selecionados por sorteio. RESULTADOS: A prevalência de sibilos no último ano foi 15,8 por cento, e de asma ou bronquite alguma vez na vida 23,8 por cento, sem diferença significativa entre sexos. Houve diferença estatística (p<0,05) entre sexos (feminino e masculino, respectivamente) em sibilos alguma vez na vida (37,8 por cento e 33,6 por cento), sono alterado devido à crise de sibilos (13,7 por cento e 9,5 por cento) e tosse seca noturna sem infecção respiratória (36,6 por cento e 28,7 por cento). Houve associação nociva entre sibilos no último ano, contato com animais domésticos (OR=1,27; IC 95 por cento: 1,03-1,56) e história familiar de asma (OR=1,79; IC 95 por cento: 1,50-2,14), e associação protetora entre sibilos no último ano e localização rural da escola (OR=0,63; IC 95 por cento: 0,44-0,91), mas não houve associação com sexo, idade, domínio escolar e tabagismo passivo. CONCLUSÕES: A prevalência de asma na amostra estudada foi elevada, com alguns sintomas predominantes no sexo feminino. A ocorrência de sibilos no último ano mostrou-se associada à história familiar, contato com animais domésticos e localização urbana das escolas.

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