• Energy Research
• PT close

Humans are exposed to complex mixtures of phthalates. Gestational exposure to phthalates has been linked to preeclampsia and preterm birth through potential pathways such as endocrine disruption, oxidative stress, and inflammation. Eicosanoids are bioactive signaling lipids that are related to a variety of homeostatic and inflammatory processes. We investigated associations between urinary phthalates and their mixtures with plasma eicosanoid levels during pregnancy using the PROTECT cohort in Puerto Rico (N = 655). After adjusting for covariates, we estimated pair-wise associations between the geometric mean of individual phthalate metabolite concentrations across pregnancy and eicosanoid biomarkers using multivariable linear regression. We used bootstrapping of adaptive elastic net regression (adENET) to evaluate phthalate mixtures associated with eicosanoids and subsequently create environmental risk scores (ERS) to represent weighted sums of phthalate exposure for each individual. After adjusting for false-discovery, in single-pollutant analysis, 14 of 20 phthalate metabolites or parent compound indices showed significant and primarily negative associations with multiple eicosanoids. In our mixture analysis, associations with several metabolites of low molecular weight phthalates - DEP, DBP, and DIBP - became prominent. Additionally, MEHHTP and MECPTP, metabolites of a new phthalate replacement, DEHTP, were selected as important predictors for determining the concentrations of multiple eicosanoids from different pathway groups. A unit increase in phthalate ERS derived from bootstrapping of adENET was positively associated with several eicosanoids mainly from Cytochrome P450 pathway. For example, an increase in ERS was associated with 11(S)-HETE (β = 1.6, 95% CI: 0.020, 3.180), (±)11,12-DHET (β = 2.045, 95% CI: 0.250, 3.840), 20(S)-HETE (β = 0.813, 95% CI: 0.147, 1.479), and 9 s-HODE (β = 2.381, 95% CI: 0.657, 4.104). Gestational exposure to phthalates and phthalate mixtures were associated with eicosanoid levels during pregnancy. Results from the mixture analyses underscore the complexity of physiological impacts of phthalate exposure and call for further in-depth studies to examine these relationships.

Humans are exposed to complex mixtures of phthalates. Gestational exposure to phthalates has been linked to preeclampsia and preterm birth through potential pathways such as endocrine disruption, oxidative stress, and inflammation. Eicosanoids are bioactive signaling lipids that are related to a variety of homeostatic and inflammatory processes. We investigated associations between urinary phthalates and their mixtures with plasma eicosanoid levels during pregnancy using the PROTECT cohort in Puerto Rico (N = 655). After adjusting for covariates, we estimated pair-wise associations between the geometric mean of individual phthalate metabolite concentrations across pregnancy and eicosanoid biomarkers using multivariable linear regression. We used bootstrapping of adaptive elastic net regression (adENET) to evaluate phthalate mixtures associated with eicosanoids and subsequently create environmental risk scores (ERS) to represent weighted sums of phthalate exposure for each individual. After adjusting for false-discovery, in single-pollutant analysis, 14 of 20 phthalate metabolites or parent compound indices showed significant and primarily negative associations with multiple eicosanoids. In our mixture analysis, associations with several metabolites of low molecular weight phthalates - DEP, DBP, and DIBP - became prominent. Additionally, MEHHTP and MECPTP, metabolites of a new phthalate replacement, DEHTP, were selected as important predictors for determining the concentrations of multiple eicosanoids from different pathway groups. A unit increase in phthalate ERS derived from bootstrapping of adENET was positively associated with several eicosanoids mainly from Cytochrome P450 pathway. For example, an increase in ERS was associated with 11(S)-HETE (β = 1.6, 95% CI: 0.020, 3.180), (±)11,12-DHET (β = 2.045, 95% CI: 0.250, 3.840), 20(S)-HETE (β = 0.813, 95% CI: 0.147, 1.479), and 9 s-HODE (β = 2.381, 95% CI: 0.657, 4.104). Gestational exposure to phthalates and phthalate mixtures were associated with eicosanoid levels during pregnancy. Results from the mixture analyses underscore the complexity of physiological impacts of phthalate exposure and call for further in-depth studies to examine these relationships.

In the current situation with the unprecedented deployment of clean technologies for electricity generation, it is natural to expect that storage will play an important role in electricity networks. This paper provides a qualitative methodology to select the appropriate technology or mix of technologies for different applications. The multiple comparisons according to different characteristics distinguish this paper from others about energy storage systems. Firstly, the different technologies available for energy storage, as discussed in the literature, are described and compared. The characteristics of the technologies are explained, including their current availability. In order to gain a better perspective, availability is cross-compared with maturity level. Moreover, information such as ratings, energy density, durability and costs is provided in table and graphic format for a straightforward comparison. Additionally, the different electric grid applications of energy storage technologies are described and categorised. For each of the categories, we describe the available technologies, both mature and potential. Finally, methods for connecting storage technologies are discussed.

In the current situation with the unprecedented deployment of clean technologies for electricity generation, it is natural to expect that storage will play an important role in electricity networks. This paper provides a qualitative methodology to select the appropriate technology or mix of technologies for different applications. The multiple comparisons according to different characteristics distinguish this paper from others about energy storage systems. Firstly, the different technologies available for energy storage, as discussed in the literature, are described and compared. The characteristics of the technologies are explained, including their current availability. In order to gain a better perspective, availability is cross-compared with maturity level. Moreover, information such as ratings, energy density, durability and costs is provided in table and graphic format for a straightforward comparison. Additionally, the different electric grid applications of energy storage technologies are described and categorised. For each of the categories, we describe the available technologies, both mature and potential. Finally, methods for connecting storage technologies are discussed.

Abstract Grape pomace is a by-product of the wine making industry with great availability and energetic potential. Torrefaction is a pre-treatment that may enhance the biomass quality as a fuel, and consists in exposing the biomass to an inert atmosphere at a temperature between 200 °C and 300 °C. This study evaluates the combustion characteristics of raw and torrefied grape pomace in a thermogravimetric analyzer and in a drop tube furnace. Initially, the raw grape pomace was torrefied in an argon inert atmosphere at 260 °C. Subsequently, the combustion of the raw and torrefied grape pomace was examined in the thermogravimetric analyzer through non-isothermal runs at a heating rate of 10 °C/min from room temperature to 800 °C. Finally, the combustion of both biomass residues was evaluated in the drop tube furnace at 1100 °C. The data reported includes gas temperature, major gas species concentration and particle burnout measured along the axis of the drop tube furnace. The main conclusions of this study are (i) for the devolatilization stage, the thermogravimetric data yielded apparent activation energy values of 84.9 and 85.2 kJ mol−1, and for the char oxidation stage of 137.5 and 109.2 kJ mol−1 for the raw and torrefied grape pomace, respectively; (ii) the NOx concentrations along the drop tube furnace were always higher for the combustion of the torrefied grape pomace than for the combustion of the raw grape pomace because the former residue has a higher nitrogen content; and (iii) the burnout values along the drop tube furnace were always lower for the combustion of the torrefied grape pomace than for the combustion of the raw grape pomace because the former residue has a lower volatile content and a higher fixed carbon content.

Abstract Grape pomace is a by-product of the wine making industry with great availability and energetic potential. Torrefaction is a pre-treatment that may enhance the biomass quality as a fuel, and consists in exposing the biomass to an inert atmosphere at a temperature between 200 °C and 300 °C. This study evaluates the combustion characteristics of raw and torrefied grape pomace in a thermogravimetric analyzer and in a drop tube furnace. Initially, the raw grape pomace was torrefied in an argon inert atmosphere at 260 °C. Subsequently, the combustion of the raw and torrefied grape pomace was examined in the thermogravimetric analyzer through non-isothermal runs at a heating rate of 10 °C/min from room temperature to 800 °C. Finally, the combustion of both biomass residues was evaluated in the drop tube furnace at 1100 °C. The data reported includes gas temperature, major gas species concentration and particle burnout measured along the axis of the drop tube furnace. The main conclusions of this study are (i) for the devolatilization stage, the thermogravimetric data yielded apparent activation energy values of 84.9 and 85.2 kJ mol−1, and for the char oxidation stage of 137.5 and 109.2 kJ mol−1 for the raw and torrefied grape pomace, respectively; (ii) the NOx concentrations along the drop tube furnace were always higher for the combustion of the torrefied grape pomace than for the combustion of the raw grape pomace because the former residue has a higher nitrogen content; and (iii) the burnout values along the drop tube furnace were always lower for the combustion of the torrefied grape pomace than for the combustion of the raw grape pomace because the former residue has a lower volatile content and a higher fixed carbon content.

Nos últimos anos, muitos daqueles que têm definido estratégias e políticas para os destinos turísticos urbanos têm vindo a preocupar-se cada vez mais com a maior ou menor capacidade de fruição do espaço público. O facto de as áreas urbanas continuarem em crescimento à escala mundial tem provocado alterações significativas no (micro)clima, por efeito do aumento de superfícies impermeabilizadas, pelo calor antropogénico gerado pelas atividades humanas e pela alteração da circulação do ar. Para fazer face às crescentes exigências dos turistas e dos residentes e à necessidade de melhorar as cidades perante um cenário de alterações climáticas, é fundamental desenhar novas medidas e soluções de atuação. No entanto, nos trabalhos de investigação sobre esta temática é usual a ausência e a falta de qualidade dos dados utilizados, assim como a sua baixa resolução espacial. Estas dificuldades, aliadas à escassez de estruturas adequadas para a partilha de informação, limitam significativamente as ações que possam ser encetadas. A presente investigação visa identificar os principais métodos de análise para monitorizar a capacidade de fruição turística atual partindo da integração dos domínios objetivo e subjetivo; e contribuir para a delimitação de planos de atuação que procurem mitigar e adaptar o setor turístico às alterações climáticas, a médio e a longo prazo. Para aferir a validade destas premissas, foi utilizado como estudo de caso a Área Metropolitana do Porto, em geral, e o município do Porto, em particular. Com recurso a esta investigação, fica patente como se cruzaram diferentes métodos de informação e unidades de análise, assentes numa abordagem meso e escala local baseada na: (i) identificação das áreas críticas, numa análise de gabinete alicerçada essencialmente em Big Data (i.e., fotografias do Flickr, alojamentos de AirBnB e imagens de satélite); (ii) avaliação do nível de conforto térmico para a fruição em áreas críticas com elevado potencial turístico através de levantamento de dados em terreno; e na (iii) identificação de ações e medidas de priorização para a manutenção da atratividade turística face às alterações climáticas. A investigação coloca em evidência a necessidade de informação mais detalhada, a fraca interação entre os atores e a limitação dos recursos. Deste modo, considerando que o Porto é hoje um destino turístico com um clima ameno para a prática turística e procurando mitigar os efeitos das alterações climáticas, este cruzamento metodológico permite delinear algumas medidas e ações com previsibilidade de atuação a curto, médio e longo prazo, tendo em conta a capacidade de fruição turística nas áreas urbanas. Por fim, este estudo procura dar alguns contributos a nível nacional e internacional, podendo a abordagem metodológica adotada ser replicada noutras áreas geográficas, tendo em conta as particularidades de cada território de análise. En los últimos años, muchos de los que han definido estrategias y políticas para los destinos turísticos urbanos se han preocupado cada vez más por la mayor o menor capacidad de disfrutar del espacio público. El hecho de que las áreas urbanas sigan creciendo a escala mundial ha provocado cambios importantes en el (micro)clima, debido al aumento de superficies impermeables, el calor antropogénico generado por las actividades humanas y el cambio en la circulación del aire. Para satisfacer las crecientes demandas de turistas y residentes y la necesidad de mejorar las ciudades ante el cambio climático, es fundamental diseñar nuevas medidas y soluciones de actuación. Sin embargo, en las investigaciones sobre este tema es común la ausencia y falta de calidad de los datos utilizados, así como su baja resolución espacial. Estas dificultades, junto con la escasez de estructuras adecuadas para compartir información, limitan significativamente las acciones que se pueden tomar. La presente investigación tiene como objetivo identificar los principales métodos de análisis para monitorear la capacidad actual de disfrute turístico a partir de la integración de dominios objetivos y subjetivos; y contribuir a la definición de planes de acción que busquen mitigar y adaptar el sector turístico al cambio climático, en el medio y largo plazo. Para evaluar la validez de estas premisas, se utilizó como estudio de caso el Área Metropolitana de Oporto, en general, y el municipio de Oporto, en particular. En esta investigación queda claro cómo los diferentes métodos de información y unidades de análisis se entrelazan, usando enfoques de escala meso y local, con: (i) la identificación de áreas críticas, en un análisis basado esencialmente en Big Data (es decir, fotos de Flickr, alojamientos AirBnB e imágenes de satélite); (ii) la evaluación del nivel de confort térmico para el disfrute en áreas críticas con alto potencial turístico a través de la recolección de datos de campo; y (iii) la identificación de acciones y medidas de priorización para mantener el atractivo turístico frente al cambio climático. La investigación destaca la necesidad de información más detallada, la débil interacción entre actores y los recursos limitados. Así, considerando que Oporto es hoy un destino turístico con un clima templado para el turista y que busca mitigar los efectos del cambio climático, este cruce metodológico permite delinear algunas medidas y acciones con previsibilidad de acción en el corto, medio y largo plazo, teniendo en cuenta la capacidad de disfrute turístico en las zonas urbanas. Finalmente, este estudio busca hacer algunas aportaciones a nivel nacional e internacional, al tiempo que el enfoque metodológico adoptado puede ser replicado en otras áreas geográficas, teniendo en cuenta las particularidades de cada territorio bajo análisis. In recent years, those who create strategies and policies for urban tourist destinations have been increasingly concerned with the greater or lesser capacity to enjoy public space. Furthermore, the growth of urban areas on a global scale has caused significant changes in the (micro)climate, due to the increase in impermeable surfaces, the anthropogenic heat generated by human activities and the change in air circulation. Taking into account the increasing demands of tourists and residents and the need to improve cities in the face of climate change, the option is to design new measures and action solutions. However, the lack of quality of the input data or their (total) absence, as well as their low spatial resolution, are common. The inadequacy of structures for sharing information is also noted, which significantly limits planning and adaptation actions. This investigation aims to identify the main methods of analysis to monitor the current ability to enjoy tourism based on the integration of objective and subjective domains; and contribute to the definition of action plans which seek to mitigate and adapt the tourism sector to climate change, in the medium and long-term. To assess the validity of these assumptions, the Porto Metropolitan Area, in general, and the municipality of Porto, in particular, were used as case studies. In this investigation, different methods of information and units of analysis were combined, based on a meso approach and local scale for: (i) the identification of critical areas, in an office analysis based essentially on Big Data (i.e., Flickr photographs, AirBnB accommodation and MODIS and LANDSAT satellite imagery); (ii) the assessment of the comfort level for enjoyment in critical areas with high tourist potential through field data collection; and (iii) the identification of prioritization actions and measures to maintain tourism attractiveness in view of climate change, in the medium and long-term. This research highlights the need for more detailed information, the weak interaction between stakeholders and the limitation of resources. Thus, considering that Porto is a destination with a good climate for tourism, and committed to mitigating the effects of climate change, the proposed methodological triangulation allows to outline some measures with predictable action in the short, medium and long-term. Finally, this study aims to make some contributions at national and international level, with the likelihood of the methodological approach adopted to be replicated in other geographical areas, taking into account the particularities of each territory under analysis. Tese de doutoramento em Geografia (especialização em Geografia e Planeamento Regional) Fundação para a Ciência e a Tecnologia (FCT Portugal) - SFRH/BD/129153/2017