Fractal Photonic Crystal Waveguides

We propose a new class of one-dimensional (1D) photonic waveguides: the fractal photonic crystal waveguides (FPCWs). These structures are photonic crystal waveguides (PCWs) etched with fratal distribution of grooves such as Cantor bars. The transmission properties of the FPCWs are investigated and compared with those of the conventional 1D PCWs. It is shown that the FPCW transmission spectrum has self-similarity properties associated with the fractal distribution of grooves. Furthermore, FPCWs exhibit sharp localized transmissions peaks that are approximately equidistant inside the photonic band gap

Experiências da prática profissional na reabilitação: análise de um grupo de foco

O objetivo desta investigação foi reconhecer as perceções dos múltiplos intervenientes acerca dos problemas encontrados nos processos de reabilitação do património habitacional. Os dados foram recolhidos através de um inquérito orientado para um grupo de foco. O estudo contou com um total de 108 participantes, incluindo arquitetos, engenheiros, construtores e técnicos de construção e restauro e potenciais promotores. Os dados foram analisados com recurso a métodos de investigação qualitativa, nomeadamente análises temáticas e de conteúdo. Os resultados demonstram que os principais problemas identificados estão relacionados com a informação, com o fator económico, com a perceção social e a qualificação dos intervenientes. Foi também possível identificar aspetos positivos no processo, nomeadamente a motivação encontrada em participar na valorização do carácter dos lugares, mas também um maior reconhecimento dos contributos das técnicas tradicionais para a sustentabilidade. Os resultados demonstram que, para que as boas práticas de reabilitação sejam aplicadas de modo efetivo, é necessário melhorar a transmissão dessa informação para a prática profissional, criando ferramentas que permitam apoiar a tomada de decisão ponderada, considerando um leque mais abrangente de critérios para além do económico (como o impacte ambiental, a saúde dos ocupantes, ou o valor patrimonial).info:eu-repo/semantics/publishedVersio

Survey to architects: challenges to inspection and diagnosis in historical residential buildings

Using a web query among architects (n=57), we could identify the main obstacles found in the application of inspection and diagnosis procedures in historical residential buildings.  The results revealed that these procedures are not yet uniformly applied in this built heritage and pointed out the need to develop simplified methodologies and less resource-consuming methodologies, to ensure their applicability.The authors would like to acknowledge the support granted by the Portuguese Foundation for Science and Technology (FCT), in the scope of the Doctoral Program Eco-Construction and Rehabilitation (EcoCoRe), to the PhD scholarship with the reference PD/BD/127853/2016 that was fundamental for the development of this study.info:eu-repo/semantics/publishedVersio

Economic valuation of life cycle environmental impacts of construction products - A critical analysis

The aim of this paper is to identify existing methods for economic valuation or monetisation of life cycle environmental impacts and to assess its applicability in the broad European context. Although environmental awareness is more and more important in several industrial sectors, including the construction sector, easy to understand data are still missing for professionals to assess and manage impacts related to the whole life cycle of a building. Life Cycle Assessment (LCA) is one of the most commonly accepted methodologies to calculate potential life cycle environmental impacts of a product or service. However, the results of such method, even when published in an Environmental Product Declaration, meant for business to business communication, are not always comparable or easily understandable by non-practitioners. Economic valuation or monetisation of LCA results is a weighting step that can make it easier for non-practitioners to use LCA results to support decision-making. From the several monetisation methods analysed, it is discussed the one that is most suitable for use when LCA results already exist. It is concluded that further work is needed to improve such weighting methods or develop a common one that can be representative at a broader geographical level (for instance, Europe-wide).This work was supported by FCT - Fundação para a Ciência e Tecnologia [grant number PD/BD/127850/2016] under the Doctoral Program EcoCoRe - Eco-Construction and Rehabilitation. Support from CERIS and Instituto Superior Técnico is also acknowledged

Caracterización de defectos, diagnóstico y reparación de suelos de madera basado en un estudio de campo

A statistical characterization of defects in 35 buildings and 98 wood floorings (softwood and hardwood floors, and laminated and engineered wood floors), their diagnostic methods and repair solutions is presented. An expert system for inspecting wood flooring, comprising the classification of defects, their most probable causes, diagnostic methods and repair techniques, was used. Results include age, affected area, severity and frequency of defects and their main causes, as well as appropriate diagnostic methods, preventive and curative repair solutions most prescribed and the most significant correlations. Scratches were detected in more than five sixths of the sample, highly associated with exterior mechanical actions, and with an inadequate finishing layer. Wearing of the finishing layer was detected in a quarter of the inspected floorings. Accordingly, the application of a suitable finishing layer and, alternatively, its replacement are the most prescribed repair techniques.Se presenta una caracterización estadística de defectos en 35 edificios y 98 suelos de madera (sue-los de madera conífera y frondosa, pisos de madera laminada e de ingeniería de la madera), sus métodos de diagnóstico y soluciones de reparación. Se utilizó un sistema experto para inspeccionar suelos de madera, que incluía la clasificación de defectos, sus causas más probables, métodos de diagnóstico y técnicas de reparación. Los resultados incluyen edad, área afectada, gravedad y frecuencia de los defectos y sus principales causas, así como los métodos de diagnósticos apropiados, soluciones de reparación preventiva y curativa más prescritas y las correlaciones más significativas. Se detectaron arañazos en más de cinco sextos de la muestra, muy asociados con acciones mecánicas exteriores y con una capa de acabado inadecuada. El desgaste de la capa de acabado se detectó en un cuarto de los suelos inspeccionados. Por consiguiente, la aplicación de una capa de acabado adecuado y, en su caso, su sustitución son las técnicas de reparación más prescritas

Comprehensive Insight into the Elderflowers and Elderberries (Sambucus nigra L.) Mono and Sesquiterpenic Metabolites: Factors that Modulate Their Composition

Plant secondary metabolites are synthesized for their protection and regulation purposes. Quite often, due to their properties, these metabolites have relevant organoleptic and biological properties and can play important roles in human health and general well-being. A relevant case study in this context is berries and flowers from Sambucus nigra L., which have been used for generations in folk medicine. Although those effects are mainly linked to phenolic compounds, mono and sesquiterpenic secondary metabolites may also play a key role. Despite their potential, S. nigra mono and sesquiterpenic compounds are yet largely unexplored. Complex and dynamic external and internal plant-related phenomena deeply affect terpenes profile, as metabolism, abiotic and biotic stresses, and understanding these phenomena is the first step for S. nigra berries and flowers’ valuation. This chapter will cover aspects linked to elder plant uses, mono and sesquiterpenic composition, and the influence of preharvest and postharvest effects over these metabolites. This knowledge is crucial for scientists and industries to understand and improve the quality of S. nigra-based products

Going beyond good intentions for the sustainable conservation of built heritage: a systematic literature review

This research addresses the performance gap between intentions towards a sustainable conservation of built heritage and its actual implementation. Socio-psychological models of human behaviour, such as the theory of planned behaviour (TPB), have been studying this dissonance between intention and behaviour, and allow to recognise latent critical factors. This paper provides a systematic literature review of research publications on the intersection of the topics of human behaviour, heritage, and sustainability. It aims to analyse how the TPB has been used in the field of sustainable conservation of built heritage. The studies are categorised according to the type of heritage, main actors targeted, aims, and methodology. A total of 140 publications were analysed. The results show a recent field of research. In the domain of built heritage conservation, behaviour is commonly addressed as a synonym of performance, targeting the building itself. Most publications relating socio-psychological constructs of behaviour and heritage sustainability can be found in the tourism and hospitality field, focusing on tourists’ and residents’ behaviours. The review shows that practitioners are still absent from the literature. However, research addressing other stakeholders shows that the theoretical framework can play an important role in the implementation of sustainable conservation practices in the built heritage.This research was funded by the Portuguese Foundation for Science and Technology (FCT) in the scope of the Doctoral Program Eco-Construction and Rehabilitation (EcoCoRe), to the PhD scholarship with the reference PD/BD/127853/201

PHENIX first measurement of the J/psi elliptic flow parameter v2 in Au+Au collisions at sqrt(sNN) = 200 GeV

Recent results indicate that the J/psi suppression pattern differs with rapidity showing a larger suppression at forward rapidity. J/psi suppression mechanisms based on energy density (such as color screening, interaction with co-movers, etc.) predict the opposite trend. On the other hand, it is expected that more c\bar{c} pairs should be available to form quarkonia at mid-rapidity via recombination. Some models provide a way to differentiate J/psi production from initially produced c\bar{c} pairs and final state recombination of uncorrelated pairs, via the rapidity and transverse momentum dependence of the elliptic flow (v2). During 2007 data taking at RHIC, a large sample of Au+Au collisions at sqrt(sNN)=200 GeV was collected. The statistics has been increased compared to previous 2004 data set, thus allowing a more precise measurement of the J/psi production at both mid and forward rapidity. Furthermore, the PHENIX experiment benefited from the addition of a new detector, which improves the reaction plane resolution and allows us to measure the J/psi v2. Comparing this measurement to the positive D-mesons v2 (through non-photonic electron decays) will help constraining the J/psi production mechanisms and getting a more precise picture of the proportion of J/psi coming from direct production or charm quark coalescence. Details on how the J/psi v2 is measured at both rapidities are presented. The J/psi v2 as a function of transverse momentum are compared to existing models.Comment: 4 pages, 3 figures, Quark Matter 2008 proceeding

Determination of the Hydroxy and Carboxylic Acid Groups in Natural Complex Mixtures of Hydroxy Fatty Acids by (1)H Nuclear Magnetic Resonance Spectroscopy

The use of trichloroacetyl isocyanate (TAI) to mark both hydroxyl and carboxyl groups borne by the hydrolysis or methanolysis of suberin fragments (a complex mixture of hydroxy fatty acids), allowed the quantitative assessment of the ratio between carboxyl and hydroxy groups, as well as the ratio between primary and secondary hydroxy groups, to be carried out reliably by (1)H nuclear magnetic resonance (NMR) spectroscopy. All the samples thus analyzed displayed an excess of CO(2)H (or CO(2)CH(3)) functions with respect to the OH counterparts, albeit to a variable extent, depending on the procedure adopted to isolate the suberin fragments. The precise knowledge of the molar ratio of these two reactive moieties is fundamental for the correct utilization of suberin monomers in polymerization reactions leading to aliphatic polyesters.FCT - SFRH/ BD/38890/200

Comparative analysis of ferroelectric domain statistics via nonlinear diffraction in random nonlinear materials

© 2018 [Optical Society of America]. Users may use, reuse, and build upon the article, or use the article for text or data mining, so long as such uses are for non-commercial purposes and appropriate attribution is maintained. All other rights are reserved.We present an indirect, non-destructive optical method for domain statistic characterization in disordered nonlinear crystals having homogeneous refractive index and spatially random distribution of ferroelectric domains. This method relies on the analysis of the wave-dependent spatial distribution of the second harmonic, in the plane perpendicular to the optical axis in combination with numerical simulations. We apply this technique to the characterization of two different media, Calcium Barium Niobate and Strontium Barium Niobate, with drastically different statistical distributions of ferroelectric domains.Peer ReviewedPostprint (published version