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The human umbilical cord tissue-derived MSC population UCX® promotes early moto...

Mesenchymal stromal cells (MSCs) play an important role in tissue regeneration mainly through the secretion of trophic factors that enhance the repair of damaged tissues. The main goal of this work was to study the paracrine mechanisms by which an umbilical cord tissue-derived MSC population (UCX®) promotes the migration capacity of human dermal fibroblasts and keratinocytes, which is highly relevant for skin r...

Comportamento semi-rígido de ligações tradicionais de madeira

Apresentam-se os principais resultados de uma campanha experimental sobre ligações tradicionais de madeira. Através de ensaios monotónicos e cíclicos, analisaram-se ligações originais (não reforçadas) e estudaram-se três soluções típicas de reforço, nomeadamente, soluções com recurso a: braçadeira, esquadro e varões. Com base nestes resultados experimentais foi implementado e calibrado um modelo simplificado pa...

Field load tests on a Queen-post timber truss

In-situ cyclic tests on a Portuguese Queen-post timber truss were performed. The main goal of the tests was to evaluate the overall behaviour of the timber truss under symmetric and nonsymmetric loading. Moreover, the influence of the number and location of point loads, without and with eccentricity relatively to joints, was assessed. The carrying tests were preceded by a visual inspection and non-destructive e...

Comportamento semi-rígido de ligações tradicionais de madeira

Apresentam-se os principais resultados de uma campanha experimental sobre ligações tradicionais de madeira. Através de ensaios monotónicos e cíclicos, analisaram-se ligações originais (não reforçadas) e estudaram-se três soluções típicas de reforço, nomeadamente, soluções com recurso a: braçadeira, esquadro e varões. Com base nestes resultados experimentais foi implementado e calibrado um modelo simplificado pa...

Chemical carcinogenesis

The use of chemical compounds benefits society in a number of ways. Pesticides, for instance, enable foodstuffs to be produced in sufficient quantities to satisfy the needs of millions of people, a condition that has led to an increase in levels of life expectancy. Yet, at times, these benefits are offset by certain disadvantages, notably the toxic side effects of the chemical compounds used. Exposure to these ...

Evolution strategies in optimization problems

Evolution strategies are inspired in biology and form part of a larger research field known as evolutionary algorithms. Those strategies perform a random search in the space of admissible functions, aiming to optimize some given objective function. We show that simple evolution strategies are a useful tool in optimal control, permitting one to obtain, in an efficient way, good approximations to the solutions of...

Chemical carcinogenesis

Modelling of timber joints in traditional structures

Original unstrengthened timber connections and the effects of different strengthening techniques have been evaluated experimentally with tests on full-scale birdsmouth joints. Experimental results show that structural response of traditional timber connections under cyclic loading cannot be represented by common constraint models, like perfect hinges or rigid joints, but should be using semi-rigid and friction ...

DNA study of bladder papillary tumours chemically induced by N-butyl-N-(4-hydro...

Behaviour of traditional Portuguese timber roof structures

The aim of this paper is to present the results of a structural analysis of common trusses traditionally used in roof construction in Portugal. The study includes the results of a preliminary survey intending to assess the geometry, materials and on site pathologies, as well as a twodimensional linear elastic static and dynamic analysis. The trusses behaviour under symmetric and non-symmetric loads, the king po...