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Portugal é um dos países da União Europeia que possui maior percentagem de população com idade igual ou superior a 65 anos – 21,1% em 2017 (SAKELLARIDES, 2019), sendo o índice de envelhecimento de 159,4 pessoas idosas por cada 100 jovens (INE, 2019). Tal realidade comporta, necessariamente, implicações e desafios a que importa atender na edificação de uma sociedade democrática, justa e promotora do fortalecimento das pessoas de todas as idades (LIMA, 2016). O envelhecimento, enquanto processo inerente à vida do ser humano é experienciado de forma diferente pelos indivíduos, em função de múltiplas dimensões, com impacto no corpo e na aparência (BLESSMANN, 2004). Nesse sentido, considerando o paradigma do envelhecimento ativo – enquanto processo de otimização das oportunidades para a saúde, participação e segurança, e de promoção da melhoria da qualidade de vida durante o envelhecimento (OMS, 2005) bem como o do envelhecimento saudável (OMS, 2015) – enquanto processo de desenvolvimento e manutenção da capacidade funcional que permite o bem-estar em idade avançada, marcando a trajetória de saúde de cada indivíduo, considerou-se premente investigar a perceção de pessoas idosas sobre o seu corpo. Relata-se aqui um estudo de natureza exploratória, ainda em curso (enquadrado num estudo comparativo entre Portugal e Polónia), onde se inquiriram 19 pessoas com 60+ anos de idade a frequentar 2 Universidades Seniores do Norte de Portugal, a fim de dar resposta à questão «Como é que pessoas idosas que frequentam a universidade sénior veem o seu corpo?». Os principais resultados evidenciam: i) uma perceção de corpo enquanto ‘realidade biológica’; ii) que os/as participantes cuidam do seu corpo; iii) que as pessoas idosas, atualmente, têm ‘preocupação com a sua aparência’; iv) sendo ‘o enfoque atual na corporalidade um desafio para todos/as e não apenas para as pessoas idosas’.

Photovoltaic (PV) technologies are in constant development, but all of them present limitations. One way of increasing the spectral range of absorbed sunlight, is through the use of spectral converters able to absorb radiation which is not used by PV cells and convert it to radiation with a usable energy. They can be converting layers (down-shifting or up-converting) applied on PV cells surface or luminescent solar concentrators, complementary devices specially indicated for urban integration of PV devices. Most of the works focus on the optically active centers, but the choice of the host matrix to disperse them is also of great importance. In this sense, the use of sol-gel processed materials have been applied due to the appealing synthesis procedure inherent of this technique. Here, a review on state-of-the-art spectral converting devices is provided, with special attention to the studies in which sol-gel processed materials play a determinant role. published

The mismatch between the photovoltaic (PV) cells absorption and the solar irradiance on earth is one of the major limitations towards more efficient PV energy conversion. This aspect was addressed by down-shifting the solar irradiance on Earth through luminescent down-shifting layers based on lanthanide-doped surface-functionalized ionosilicas (ISs) embedded in poly(methyl methacrylate) (PMMA) coated on the surface of commercial Si-based PV cells. The IS-PMMA hybrid materials exhibit efficient solar radiation harvesting (spectral overlap of ∼9.5 × 1019 photons/(s·m2)) and conversion (quantum yield ∼52%). The direct solar radiation and the down-shifted radiation are partially guided and lost through total internal reflection to the layer edges being unavailable for PV conversion of the coated PV cell. By tuning the down-shifting layer thickness, it also acts as luminescent solar concentrator enabling the collection of the guided radiation by flexible PV cells applied on the borders of the down-shifting layer leading to an enhancement of the PV energy conversion from ∼5% (in the case of the single-use of the luminescent down-shifting layer) to ∼13% comparing with the bare PV cell. The overall electrical output of the device resulted in an absolute external quantum efficiency increase of ∼32% for the optimized Eu3+-based films in the UV spectral region (compared with the bare PV device, which is among the best values reported so far).

Luminescent solar concentrators (LSCs) are luminescent waveguide layers that convert sunlight into specific wavelengths which are then guided by total internal reflection to a PV device located at the edges of the LSC. Their ability to concentrate sunlight onto small areas makes LSCs a useful complement to silicon-based PVs in a series of applications, such as urban integration and flexible fabrics towards mobile solar-energy. Challenges for the luminescent layer include the use of low-cost and sustainable nature-based organic molecules. We report novel chlorophyll-based LSCs with emission properties in the red/NIR spectral region. Here, chlorophyll molecules extracted from Spirulina maxima, an abundant cyanobacterium and an attractive natural source, are immobilized in organic–inorganic di- and tri-ureasil matrices enabling the production of sustainable LSCs. At low chlorophyll concentrations (, Funding was provided by Fundaçao para a Ciencia e a Tecnologia (FCT), EU/FEDER COMPETE and Mais Centro-PORC, under contracts PEST-OE/EEI/LA0008/2013 and CENTRO-07-ST24- FEDER-002032. This work was developed within the scope of the projects CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), SusPhotoSolutions – Soluçoes Fotovoltaicas Sustentaveis, CENTRO-01-0145-FEDER-000005 and Instituto de Telecomunicaçoes (FCT Ref. UID/EEA/50008/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. SFHC thanks SusPhotoSolutions for the post-doctoral grant and ARF and ARB acknowledge FCT for their PhD grants (PD/BD/114454/2016 and PD/BD/105859/2014). LDC is grateful to CAPES and CNPq (Brazil) fora fellowship within the science without borders program. SJLR acknowledges funding agency FAPESP and the Brazilian network on Photonics INFO (Instituto Nacional de Fotonica).

The integration of photovoltaic (PV) elements in urban environments is gaining visibility due to the current interest in developing energetically self-sustainable buildings. Luminescent solar concentrators (LSCs) may be seen as a solution to convert urban elements, such as fa&ccedil, ades and windows, into energy-generation units for zero-energy buildings. Moreover, LSCs are able to reduce the mismatch between the AM1.5G spectrum and the PV cells absorption. In this work, we report optically active coatings for LSCs based on lanthanide ions (Ln3+ = Eu3+, Tb3+)-doped surface functionalized ionosilicas (ISs) embedded in poly(methyl methacrylate) (PMMA). These new visible-emitting films exhibit large Stokes-shift, enabling the production of transparent coatings with negligible self-absorption and large molar extinction coefficient and brightness values (~2 &times, 105 and ~104 M&minus, 1∙cm&minus, 1, respectively) analogous to that of orange/red-emitting organic dyes. LSCs showed great potential for efficient and environmentally resistant devices, with optical conversion efficiency values of ~0.27% and ~0.34%, respectively.

We propose an optical fiber hydrostatic pressure sensor based on micro-cavities generated by the fiber fuse effect. The presented sensor is manufactured through the recycling of optical fiber destroyed by the fiber fuse effect, being, therefore, a cost-effective solution, when compared with other similar micro-cavity-based solutions. The developed sensor was characterized for pressures up to 20 kPa, showing a linear sensitivity coefficient of $0.47\pm 0.03~{\rm nm}\cdot {\rm kPa}^{-1}$ , for pressure values below 8 kPa. Furthermore, we propose a new theoretical model to describe the behavior of the microcavities embedded in optical fibers. This allows us to solve the discrepancies, already identified by other authors, between the experimental results and the ones attained with the flat mirrors Fabry-Perot model. By this way, we were able to describe the sensor response, within the full dynamic range.

Luminescent solar concentrators (LSCs) appear as candidates to enhance the performance of photovoltaic (PV) cells and contribute to reduce the size of PV systems, decreasing, therefore, the amount of material needed and thus the cost associated with energy conversion. One way to maximize the device performance is to explore near-infrared (NIR)-emitting centers, resonant with the maximum optical response of the most common Si-based PV cells. Nevertheless, very few examples in the literature demonstrate the feasibility of fabricating LSCs emitting in the NIR region. In this work, NIR-emitting LSCs are reported using silicon 2,3-naphthalocyanine bis(trihexylsilyloxide) (SiNc or NIR775) immobilized in an organic-inorganic tri-ureasil matrix (t-U(5000)). The photophysical properties of the SiNc dye incorporated into the tri-ureasil host closely resembled those of SiNc in tetrahydrofuran solution (an absolute emission quantum yield of ∼0.17 and a fluorescence lifetime of ∼3.6 ns). The LSC coupled to a Si-based PV device revealed an optical conversion efficiency of ∼1.5%, which is among the largest values known in the literature for NIR-emitting LSCs. The LSCs were posteriorly coupled to a Si-based commercial PV cell, and the synergy between the t-U(5000) and SiNc molecules enabled an effective increase in the external quantum efficiency of PV cells, exceeding 20% in the SiNc absorption region.

Luminescent solar concentrators (LSCs) are photovoltaic (PV) complementary devices to overcome the mismatch between the Si-based PV cells, response and the solar spectrum, allowing PV urban integration. Challenges for the luminescent layer include the use of abundant and sustainable natural organic molecules. Here, LSCs composed of a glass container and based on bundles of cylindrical hollow-core plastic optical fibers filled with aqueous solutions of R-phycoerythrin (R-PE), extracted from Gracilaria sp. algae are presented. The R-PE solutions absorb in the UV/visible spectral range (300–550 nm) and convert this radiation into red-emission (550–700 nm) with a maximum absolute quantum yield of ≈0.39. In this work, LSCs with distinct geometries are reported, in which the R-PE emission yields optical conversion efficiency values up to ≈6.88% and ≈4.74% for a planar device and for a bundle of cylindrical LSCs, respectively, which are the largest values known for liquid-based LCSs using sustainable emitting centres. Moreover, the coupling of the LSCs to commercial Si-based PV devices yields power conversion efficiency values of ≈0.27% (planar) and ≈23.03 × 10−3%, (bundle). These values illustrate the potential of this approach for the development of natural-based LSCs meeting the requirements of reliable, sustainable, and competitive energy systems. published

In this work, we describe a novel and cost effective approach based on optical fiber microcavities, for sensing high temperature values (up to 1150 degrees C). The proposed sensor is produced by splicing standard single mode optical fibers with fibers destroyed by the catastrophic fuse effect, resulting in a microcavity structure in the fiber core region. These microcavities have a thermal sensitivity of 10.43 +/- 0.15 pm degrees C-1, for temperatures up to 1150 degrees C, which compares well with the sensitivity of Fabry-Perot interferometric sensing cavities but with the advantage of substantially reduced manufacturing costs. (c) 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:972-974, 2015

En todo el planeta cerca de 36,7 millones de personas son portadoras del VIH/Sida, de las cuales, aproximadamente 17,1 millones lo desconoce (UNAIDS, 2016). A pesar de las sucesivas señales de progreso, que fijan la meta de erradicación de la epidemia en 2030, resta mucho por hacer, tanto a nivel de la eliminación del estigma y discriminación como a la consecución del objetivo de cero nuevas infecciones. La utilización de preservativo en todas las relaciones sexuales es una actitud preventiva fundamental pero aún está lejos de ser generalizada. Las campañas de prevención de la infección por el VIH y Sida, transmitidas a través de diversos países y destinadas a diferentes públicos, son una contribución importante en el combate de la infección y la enfermedad. Saber analizarlas críticamente no es sólo un requisito de la ciudadanía sino también una oportunidad para implementar una efectiva educación sexual. El presente artículo se centra en el análisis de la Campaña Institucional Suiza “Love Life”, producida en el año 2014, que generó gran controversia y debate en el contexto de la Unión Europea de donde surgió. Los resultados permiten concluir que se trata de una campaña “realista” (Frias, 2015) que, a pesar de pretender romper con los estereotipos de género y sexualidad, satirizar relaciones afectivas y sexuales convencionales, promover la dignidad y los derechos humanos, entre otros, todavía no es “transformadora”, debido a que presenta patrones de belleza tradicionales occidentales y no incluye a todas las personas, en particular aquellas con deficiencias físicas.

In the last decades the fiber Bragg gratings (FBG) and Fabry-Perot Interferometer (FPI) micro cavities based sensors have become one of the most attractive optical fiber sensing technologies. However, its production requires a significant economical investment. We propose a cost effective solution based on micro cavity generated by the recycling of optical fibers destroyed through the catastrophic fuse effect. This technique considerably reduces the experimental complexity and the production costs. In this paper, the application of these sensors in the monitoring of several parameters, such as refractive index, pressure, strain and temperature is presented.

Este trabalho pretende divulgar dados parciais da Investigação, “Sexualidade e Género em Campanhas de Prevenção da Infeção VIH/SIDA”, integrada no Projecto “Sexualidade e Género no discurso dos media: implicações sócio-educacionais e desenvolvimento de uma abordagem alternativa na formação de professores/as”. À luz de um quadro teóricometodológico resultante dos estudos culturais, do pós-estruturalismo, da teoria queer e da educação para os valores, discutem-se modos de educar a sexualidade e o género presentes em 31 spots publicitários de campanhas de prevenção da infeção VIH/SIDA produzidas em Portugal, entre 2000 e 2010, por Organizações Governamentais e Organizações Não Governamentais. Os resultados obtidos apontam para uma visão da sexualidade humana vinculada à normativa da heterossexualidade, dos padrões de beleza ocidental, centrada na corpo e na imagem, bem como uma naturalização dos estereótipos de género.

In this work we investigate the dynamics of the fuse effect propagation in bend loss insensitive fibers. The fuse velocity, threshold power and void period values were compared with those obtained for standard single mode fibers. The results show that the power dependent optical discharge velocity coefficient is 32 % higher in G.657 fibers than that in G.652 fibers.

In this work we compare the thermal behavior, in the fuse effect end point, of bend insensitive optical fiber (G.657) with the standard single mode fiber (G.652). We verify that the G.657 fibers display a higher average temperature value in the mentioned position, which can be explained by the shape of the final void.

The self-propelled and self-focusing catastrophic failure in optical fibres, usually designated as fibre fuse effect, is a self-destruction process induced by the propagated signal with optical power values above 1.0 W. Whilst this phenomenon was initial reported in 1988, only recently has it become a real concern for optical networks operators due to the signal power increase. Reported, for the first time, is the existence of a fuse effect discharge zone velocity nonlinear saturation regime, and experimental validation of the theoretical predictions recently developed using travelling solutions is provided.