A indústria do betão pré fabricado é, por tradição, inovadora, precursora de novas tecnologias e de novos materiais.O processo produtivo de estruturas com elementos pré-fabricados difere significativamente do das estruturas betonadas em obra pelo facto de uma parte, ou a totalidade, dos elementos da estrutura serem produzidos em fábrica, em condições de produção melhoradas em relação às condições da obra, e serem posteriormente transportados para a obra, onde são, finalmente ligados entre si. A produção em fábrica é efectuada em ambiente protegido do Sol e da chuva, com operários fixos e com formação profissional para desenvolverem tarefas com procedimentos normalizados. Consequentemente, os elementos executados em fábrica possuem melhor qualidade, sob vários aspectos, do que as estruturas executadas em obra.Este livro divide-se em duas grandes áreas, numa primeira abordam-se algumas aplicações de estruturas pré-moldadas no mundo e numa segunda parte descreve-se o seu comportamento estrutural face a diferentes acções. Nos primeiros capítulos relata-se a experiência da pré-fabricação em três países de diferentes continentes: o Brasil, Portugal e a Austrália e revelam-se novas oportunidades que poderão surgir para a indústria da pré-fabricação. Nos capítulos seguintes dá-se um especial enfoque à investigação do comportamento das ligações (rígidas e semi-rígidas). Aborda-se o projecto de estruturas de betão pré-fabricado às acções acidentais. E por fim, dedicam-se os últimos capítulos ao comportamento das estruturas pré-fabricadas face às acções sísmicas. Nesta área, o bom desempenho das estruturas e grande parte do conhecimento e da tecnologia actual advém da resposta dada pelos engenheiros, investigadores e construtores aos fenómenos naturais que afectam as nossas construções, como comprova o desempenho das ligações dúcteis resistentes a momentos em edifícios pré fabricados de betão no verdadeiro teste sísmico que foram os sismos de Christchurch de 2010 e 2011.

The layer-by-layer (LbL) assembly of polyelectrolyte pairs on temperature and pH-sensitive cross-linked poly(N-isopropylacrylamide)-co-(methacrylic acid), poly(NIPAAm-co-MAA), microgels enabled a fine-tuning of the gel swelling and responsive behavior according to the mobility of the assembled polyelectrolyte (PE) pair and the composition of the outermost layer. Microbeads with well-defined morphology were initially prepared by synthesis in supercritical carbon dioxide. Upon LbL assembly of polyelectrolytes, interactions between the multilayers and the soft porous microgel led to differences in swelling and thermoresponsive behavior. For the weak PE pairs, namely poly(l-lysine)/poly(l-glutamic acid) and poly(allylamine hydrochloride)/poly(acrylic acid), polycation-terminated microgels were less swollen and more thermoresponsive than native microgel, whereas polyanion-terminated microgels were more swollen and not significantly responsive to temperature, in a quasi-reversible process with consecutive PE assembly. For the strong PE pair, poly(diallyldimethylammonium chloride)/poly(sodium styrene sulfonate), the differences among polycation and polyanion-terminated microgels are not sustained after the first PE bilayer due to extensive ionic cross-linking between the polyelectrolytes. The tendencies across the explored systems became less noteworthy in solutions with larger ionic strength due to overall charge shielding of the polyelectrolytes and microgel. ATR FT-IR studies correlated the swelling and responsive behavior after LbL assembly on the microgels with the extent of H-bonding and alternating charge distribution within the gel. Thus, the proposed LbL strategy may be a simple and flexible way to engineer smart microgels in terms of size, surface chemistry, overall charge and permeability.The layer-by-layer (LbL) assembly of polyelectrolyte pairs on temperature and pH-sensitive cross-linked poly(N-isopropylacrylamide)-co-(methacrylic acid), poly(NIPAAm-co-MAA), microgels enabled a fine-tuning of the gel swelling and responsive behavior according to the mobility of the assembled polyelectrolyte (PE) pair and the composition of the outermost layer. Microbeads with well-defined morphology were initially prepared by synthesis in supercritical carbon dioxide. Upon LbL assembly of polyelectrolytes, interactions between the multilayers and the soft porous microgel led to differences in swelling and thermoresponsive behavior. For the weak PE pairs, namely poly(l-lysine)/poly(l-glutamic acid) and poly(allylamine hydrochloride)/poly(acrylic acid), polycation-terminated microgels were less swollen and more thermoresponsive than native microgel, whereas polyanion-terminated microgels were more swollen and not significantly responsive to temperature, in a quasi-reversible process with consecutive PE assembly. For the strong PE pair, poly(diallyldimethylammonium chloride)/poly(sodium styrene sulfonate), the differences among polycation and polyanion-terminated microgels are not sustained after the first PE bilayer due to extensive ionic cross-linking between the polyelectrolytes. The tendencies across the explored systems became less noteworthy in solutions with larger ionic strength due to overall charge shielding of the polyelectrolytes and microgel. ATR FT-IR studies correlated the swelling and responsive behavior after LbL assembly on the microgels with the extent of H-bonding and alternating charge distribution within the gel. Thus, the proposed LbL strategy may be a simple and flexible way to engineer smart microgels in terms of size, surface chemistry, overall charge and permeability.

Sandstone building stones are important in the building elements of Portuguese monuments, particularly in the western and southern regions. Alveolization due to salt crystallization was the most important degradation pattern found in the old sandstone façades of buildings in the village of Atouguia da Baleia. Because weathering progressively increases porosity in stones, experimental research was conducted on the most porous variety of sandstone, which is similar to the type of stones found in the façades of ancient buildings in that village. An automatic salt crystallization accelerated ageing chamber was developed. Monotonic and cyclic uniaxial compressive tests were carried out on samples after sodium chloride crystallization ageing tests had been performed, in order to assess the compressive mechanical behavior of sandstone during accelerated ageing. The results of stress–strain compression diagrams showed a clear decreasing trend in the values of mechanical parameters during the salt crystallization ageing progress. The difference in compressive strength values between monotonic and cyclic compression also decreases with as salt crystallization ageing progresses. A predictive equation that correlates the compressive strength of sandstones with salt crystallization ageing cycles is proposed.

Since its invention, paper has become one of the main carriers of our cultural, scientific, political, economic and historical information. Given the importance of this material, its preservation is a matter of great interest. Paper can be deteriorated due to physical, chemical and biological agents. Within microorganisms, fungi are the major paper biodeteriogens. Throughout history, several methods have been used to prevent and stop fungal deterioration on paper based materials. In this work we present a review of the main chemical and physical methods used to avoid fungal paper biodeterioration until nowadays and also of some new approaches tested recently. The advantages and disadvantages of these methods are discussed as well as their health effects. Studies regarding antifungal compositions, methods of application, performance and effects on the treated materials are also presented with the aim of providing a clear set of conclusions on the topic. (C) 2012 Elsevier Ltd. All rights reserved.

n this extended abstract we present a bidirectional model-driven framework to develop spreadsheets. By being model driven, our approach allows to evolve a spreadsheet model and automatically have the data co-evolved. The bidirectional component achieves precisely the inverse, that is, to evolve the data and automatically obtain a new model to which the data conforms.

Spreadsheets play an important role in software organizations. Indeed, in large software organizations, spreadsheets are not only used to define sheets containing data and formulas, but also to collect information from different systems, to adapt data coming from one system to the format required by another, to perform operations to enrich or simplify data, etc. In fact, over time many spreadsheets turn out to be used for storing and processing increasing amounts of data and supporting increasing numbers of users. Unfortunately, spreadsheet systems provide poor support for modularity, abstraction, and transformation, thus, making the maintenance, update and evolution of spreadsheets a very complex and error-prone task. We present techniques for model-driven spreadsheet engineering where we employ bidirectional transformations to maintain spreadsheet models and instances synchronized. In our setting, the business logic of spreadsheets is defined by ClassSheet models to which the spreadsheet data conforms, and spreadsheet users may evolve both the model and the data instances. Our techniques are implemented as part of the MDSheet framework: an extension for a traditional spreadsheet system.

Biocompatible and biodegradable water-soluble dendrimers comprising ureas within the interior and amino groups on the periphery were synthesized in supercritical carbon dioxide (dendrimer of generation 1 shown in picture). This novel class of dendrimers shows a pH-dependent intrinsic blue fluorescence at very low concentrations, which makes them potential polymeric fluorescent cell markers.

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Differently shaped polymeric matrices were efficiently coated with stimuli-responsive hydrogels for a wide range of applications using a new methodology. By combining plasma surface activation and polymerization in supercritical media at mild conditions, we report the direct smart coating of microcarriers and membranes in gram-scale quantities with a scalable, green, and low-cost approach.

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A degradação da ligação entre compósitos de matriz polimérica reforçada por fibras (FRP) e o betão é uma das principais causas de possível rotura das vigas e lajes de betão armado reforçadas
externamente por compósitos de FRP. Desde há mais de 10 anos que se estuda, por isso, na UNL o
comportamento dessa ligação, integrado em programa mais alargado de estudo da durabilidade deste tipo de reforço, especialmente quando sujeito a condições ambientais severas que se simulam por processos artificialmente acelerados no laboratório. Em particular a degradação da aderência e o possível descolamento precoce do reforço têm sido modelados física e computacionalmente com principal incidência no uso de fibras de vidro (GFRP) e resina epoxídica. Nesta comunicação mostram-se resultados obtidos em termos de capacidade de carga, força transmitida ao reforço e tensões de aderência após envelhecimentos de pequenas vigas de betão armado (BA) por ciclos de nevoeiro salino, ciclos seco/molhado em solução salina, ciclos de temperatura entre +7,5ºC e +47,5ºC e gelo-degelo de -10ºC a +30ºC. Faz-se recomendação quanto à extensão máxima para diferentes envelhecimentos. Apresenta-se comparação entre resultados de modelação numérica e experimental.

The Radio Frequency Identification (RFID) technology is a wireless technology that uses transmitted radio signals to tag, recognize, track and trace the movement of an item automatically. The study of this technology is actually considered a hot topic in all scientific areas and has been described as a major enabling technology for the automation of many processes. Although it is not a new technology it has only recently come to the awareness of the public and widely used in many sectors and particularly in the Healthcare. This paper aims to illustrate the deployment of RFID technology in Healthcare, more precisely in infant security systems. A case study about the experience of three hospitals and one RFID technology provider is presented to highlight the main architectural characteristics, functionality, and advantages associated to its deployment. After the case studies analysis it is possible to state that the infant security systems, using the RFID technology, are not so different among research case studies: they involve RFID tagging patients, they are easy to use not requiring an extensive training and also they are installed with an interface with others security systems.

Externally bonded reinforced systems have been widely used in civil engineering. However, the problems associated with bond between structural elements are not yet fully solved. As a consequence, many researchers have been proposing tests and techniques to standardize procedures and reach better agreement for design purposes. In the present paper, an experimental program is described that was developed to characterize the glass FRP/concrete interface by double shear tests made on 15 cm side cubes with GFRP bonded on two opposite faces. The GFRP wrap had two layers applied by the wet lay-up technique and three classes of concrete were considered. With the support of the experimental program, cohesion and friction angle for GFRP–concrete interfaces were found leading to different envelope failure laws, based on the Mohr–Coulomb failure criterion for each concrete class, capable of predicting GFRP debonding. Results are discussed.

Cellulosomes are highly efficient nanomachines that play a fundamental role during the anaerobic deconstruction of complex plant cell wall carbohydrates. The assembly of these complex nanomachines results from the very tight binding of repetitive cohesin modules, located in a noncatalytic molecular scaffold, and dockerin domains located at the C-terminus of the enzyme components of the cellulosome. The number of enzymes found in a cellulosome varies but may reach more than 100 catalytic subunits if cellulosomes are further organized in polycellulosomes, through a second type of cohesin-dockerin interaction. Structural studies have revealed how the cohesin-dockerin interaction mediates cellulosome assembly and cell-surface attachment, while retaining the flexibility required to potentiate catalytic synergy within the complex. Methods that might be applied for the production, purification, and structure determination of cohesin-dockerin complexes are described here. Copyright 2012 Elsevier Inc. All rights reserved.

n this paper we explore the use of models in the context of spreadsheet engineering. We review a successful spreadsheet modeling language, whose semantics we further extend. With this extension we bring spreadsheet models closer to the business models of spreadsheets themselves. An addon for a widely used spreadsheet system, providing bidirectional model-driven spreadsheet development, was also improved to include the proposed model extension.