Analysis of Motor Behavior based on Recurrence Analysis in Adults with Autism Spectrum and Neurotypicals in a Dynamic Balance Task: a pilot study / Análisis del Comportamiento Motor basado en el Análisis de Recurrencia en Adultos con Espectro Autista y Neurotípicos en una Tarea de Equilibrio Dinámico: un estudio piloto / Análise do Comportamento Motor com base na Análise de Recorrência em Adultos com Espectro deAutismo e Neurotípicos numa Tarefa de Equilíbrio Dinâmico: um estudo piloto

Introduction: Autism spectrum disorders (ASD) refers to a range of neurodevelopmental disorders with deficits in postural control (PC), motor development and coordination. The PC deficit appears to be persistent across the spectrum and can limit the acquisition of new motor skills with severe consequences in life’s’ quality. Objectives: i) to verify if the nonlinear techniques can identify the local recurrence pattern in the phase space of the PC, in individuals with ASD, ii) to compare the PC between ASD and neurotypical individuals, during a task of dynamic rotation balance. Methods: six male adult individuals, three autistic and three neurotypicals, performed a dynamic balance task, where angular velocity data was collected from the trunk. Results: Despite the inexistence of significant differences, autistic adults revealed, for all planes of movement, higher mean values of recurrence, periodicity, stability (except for the maximum line in the transversal plane), complexity and intermittence; differences that were visually confirmed by observingthe recurrence graphs. Autistic participants also revealing lower mean values of Lyapunov exponent, meaning less divergency and variability than the neurotypicals. Conclusions: the autistic’s postural control strategy of a greater periodicity, stability and a lower divergence and variability, may result from less plasticity in the ability to adjust to momentary states of postural imbalance. This strategy could be linked to the autistic’s stereotypical behavior of continuously cyclical movements. However, this does not result in greater variability in movement, but less variability. Given the neuro-motor difficulty of these autistic adults in producing varied ranges of motion, it is recommended to introduce dynamic balance activities, starting with reduced levels of postural stability disturbance. (AU)

Introducción: Los trastornos del espectro autista (TEA) se refieren a una serie de trastornos del neurodesarrollo con déficits en el control postural (CP), el desarrollo motor y la coordinación. El déficit de CP parece estar muy extendido en todo el espectro y puede limitar la adquisición de nuevas habilidades motoras con graves consecuencias en la calidad de vida. Objetivos: i) verificar si las técnicas no lineales identifican el patrón de recurrencia local en el espacio de fase de la CP en individuos con TEA, ii) comparar la CP entre individuos con TEA y neuro típico, durante una tarea de equilibrio de rotación dinámica. Métodos: seis individuos adultos del sexo masculino, tres autistas y tres neuro típico, realizaron una tarea de equilibrio dinámico, donde se recolectaron datos sobre la velocidad angular del tronco. Resultados: A pesar de la ausencia de diferencias significativas, los adultos autistas mostraron, para todos los planos de movimiento, valores medios más altos para la recurrencia, la periodicidad, la estabilidad (excepto para la línea máxima en el plano transversal), la complejidad y la intermitencia; estas diferencias se confirmaron visualmente al observar los gráficos de recurrencia. Autistas también revelaron valores medios más bajos del exponente de Lyapunov, lo que significa menos divergencia y variabilidad en comparación con los neurotípicos. Conclusiones: La estrategia de control postural de los autistas basada en mayor periodicidad, estabilidad y menor divergencia y variabilidad en el control del equilibrio puede resultar de una menor plasticidad en la capacidad de adaptación a estados momentáneos de desequilibrio postural. (AU)

Introdução: Os transtornos do espectro do autismo (TEA) referem-se a uma gama de transtornos no neuro desenvolvimento com déficits nocontrole postural (CP), desenvolvimento motor e coordenação. O déficit no CP parece ser generalizado em todo o espectro e pode limitar a aquisição de novas habilidades motoras com graves consequências na qualidade de vida. Objetivos: i) verificar se as técnicas não lineares identificam o padrão de recorrência local no espaço de fase do CP em indivíduos com TEA, ii) comparar o CP entre indivíduos com TEA e neuro típicos, durante uma tarefa de equilíbrio dinâmico de rotação. Métodos: seis indivíduos adultos do sexo masculino, três autistas e três neuro típicos, realizaram uma tarefa de equilíbrio dinâmico, onde foram recolhidos dados da velocidade angular do tronco. Resultados: Apesar da inexistência de diferenças significativas, os adultos autistas revelaram, para todos os planos de movimento, valores médios superiores de recorrência, periodicidade, estabilidade (exceto na linha máxima no plano transversal), complexidade e intermitência; diferenças estas confirmadas visualmente pela observação dos gráficos derecorrência. Os autistas revelaram ainda valores médios mais baixos do expoente de Lyapunov, significando menor divergência e variabilidade em comparação com os neurotípicos. Conclusões: A estratégia de controle postural dos autistas baseada em maior periodicidade, estabilidade e menor divergência e variabilidade no controle do equilíbrio pode resultar de uma menor plasticidade na capacidade de se ajustar a estados momentâneos de desequilíbrio postural. Esta estratégia pode estar ligada ao comportamento estereotipado dos autistas de realização contínua de movimentos cíclicos. No entanto, isso não resulta em maior variabilidade no movimento, mas em menor variabilidade. (AU)

Concrete-Based and Mixed Waste Aggregates in Rendering Mortars.

This paper presents a study of incorporation of two types of construction and demolition waste (CDW) in rendering mortars, as aggregates at 0%, 20%, 50% and 100% (by volume). Recycled concrete aggregate (RCA) and mixed recycled aggregate (MRA) were used. The former is mainly composed of cementitious waste and the latter consists of a mixture of non-segregated wastes. The performance of the cement mortars with recycled aggregates was evaluated through an extensive experimental programme. The analysis comprised workability, mechanical strength, water absorption, shrinkage, open porosity and the evaluation of durability by permeability to water under pressure after an artificial accelerated ageing test. The results are considered positive, although as the incorporation of recycled aggregates (both MRA and RCA) increased the mechanical strength, the modulus of elasticity and bulk density decreased, which leads to the production of lighter mortars that are less susceptible to cracking. The modified mortar with 20% of MRA presented the best performance, in terms of mechanical behaviour.

Wastes as Aggregates, Binders or Additions in Mortars: Selecting Their Role Based on Characterization.

The production of waste has increased over the years and, lacking a recycle or recovery solution, it is forwarded to landfill. The incorporation of wastes in cement-based materials is a solution to reduce waste deposition. In this regard, some researchers have been studying the incorporation of wastes with different functions: aggregate, binder and addition. The incorporation of wastes should take advantage of their characteristics. It requires a judicious analysis of their particles. This research involves the analysis of seven industrial wastes: biomass ashes, glass fibre, reinforced polymer dust, sanitary ware, fluid catalytic cracking, acrylic fibre, textile fibre and glass fibre. The main characteristics and advantages of each waste are enunciated and the best type of introduction in mortars is discussed. The characterization of the wastes as particles is necessary to identify the most suitable incorporation in mortars. In this research, some wastes are studied with a view to their re-use or recycling in mortars. Thus, this research focuses on the chemical, physical and mechanical characterization of industrial wastes and identification of the potentially most advantageous type of incorporation.