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Protein-bound uremic toxins, mainly indoxyl sulfate (3-INDS), p-cresol sulfate (pCS), and indole-3-acetic acid (3-IAA) but also phenol (Pol) and p-cresol (pC), are progressively accumulated during chronic kidney disease (CKD). Their accurate measurement in biomatrices is demanded for timely diagnosis and adoption of appropriate therapeutic measures. Multiana lyte methods allowing the establishment of a uremic metabolite profle are still missing. Hence, the aim of this work was to develop a rapid and sensitive method based on high-performance liquid chromatography with fuorescence detection for the simultaneous quantifcation of Pol, 3-IAA, pC, 3-INDS, and pCS in human plasma. Separation was attained in 12 min, using a monolithic C18 column and isocratic elution with acetonitrile and phosphate bufer containing an ion-pairing reagent, at a fow rate of 2 mL min−1. Standards were prepared in plasma and quantifcation was performed using the background sub traction approach. LOQ values were≤0.2 µg mL−1 for all analytes except for pCS (LOQ of 2 µg mL−1). The method proved to be accurate (93.5–112%) and precise (CV≤14.3%). The multianalyte application of the method, associated to a reduced sample volume (50 µL), a less toxic internal standard (eugenol) in comparison to the previously applied 2,6-dimethylphenol and 4-ethylphenol, and a green extraction solvent (ethanol), resulted in the AGREE score of 0.62 which is in line with the recent trend of green and sustainable analytical chemistry. The validated method was successfully applied to the analysis of plasma samples from control subjects exhibiting normal levels of uremic toxins and CKD patients presenting signifcantly higher levels of 3-IAA, pC, 3-INDS, and pCS that can be further investigated as biomarkers of disease progression.

This work compares the viscoelastic properties of an asphalt binder (70/100 pen) modified with different waste plastics and the mechanical properties of the resultant asphalt mixtures. Two different plastic wastes were used, namely recycled HDPE and EVA. Three different polymer modified binders were produced with these plastic wastes: i) 5% HDPE modified binder (P5); ii) 5% EVA modified binder (E5) and; iii) a modified binder with 4% of EVA and 2% HDPE (E4P2). Asphalt mixtures were produced with these modified binders, and their mechanical properties were analysed and compared with a conventional mixture produced with a 30/50 pen bitumen. It was possible to conclude that these recycled polymers are able to improve the mechanical performance of the asphalt mixtures used in road paving., FEDER funds through the Operational Programme for Competitiveness Factors & COMPETE and National Fund s through FCT & Foundation for Science and Technology under the project PLASTIROADS (PTDC/ECM/119179/2010) and Symposium_22 Recycling and Reuse of Wastes into New Composite Materials -2062-of the strategic project UI 4047- 2011-2012 Centre of Territory, Environment and Construction.

The aim of this study is evaluating the interaction between several base pen grade asphalt binders (35/50, 50/70, 70/100, 160/220) and two different plastic wastes (EVA and HDPE), for a set of new polymer modified binders produced with different amounts of both plastic wastes. After analysing the results obtained for the several polymer modified binders evaluated in this study, including a commercial modified binder, it can be concluded that the new PMBs produced with the base bitumen 70/100 and 5% of each plastic waste (HDPE or EVA) results in binders with very good performance, similar to that of the commercial modified binder., FEDER funds through the Operational Programme for Competitiveness Factors -COMPETE and National Funds through FCT - Foundation for Science and Technology under the project PLASTIROADS (PTDC/ECM/119179/2010) . The authors would also like to acknowledge the contribution of the company ELEVO Group through the project “Energy Efficiency and Environmental Design of Bituminous Mixtures to Reduce Emissions of Greenhouse Gases” (QREN-SI 090528), carried out in cooperation with the University of Minho

El aumento del tráfico por carretera en las últimas décadas, en combinación con un mantenimiento inadecuado llevó a un deterioro acelerado de la infraestructura vial en varios países. Un método que se destaca en la mejora de las propiedades de las mesclas bituminosas es la modificación del betún con polímeros. Aunque la modificación del polímero virgen cumple el objetivo, la modificación de betún con polímeros reciclados puede proporcionar un resultado equivalente en la mejora de las propiedades de la mescla, si se realiza una selección adecuada de los polímeros, lo betún y las condiciones de producción. La mayor preocupación ambiental y el aumento conocido en el precio del petróleo, que influye en el precio del betún, aumenta el interés en encontrar ligantes que sustituyen o disminuyen la cantidad de betún en la mezcla bituminosa. Por lo tanto, además de estudiar la modificación de los bitúmenes con polímeros reciclados, también la sustitución de 10% de betún por aceite usado de motor se ha incluido en este estudio. Los ligantes modificados se han producido entonces con polímeros vírgenes (SBS y EVA) y reciclados (EVAr y PEADr) y también con substitución de 10% de lo betún por aceite usado, que fueron sometidos a una serie de pruebas como: pruebas de caracterización básica, de estabilidad al almacenamiento y pruebas reológicas, de la que se concluyó que la adición de ambos materiales reciclados puede influir positivamente en el desempeño del ligante causando ventajas ecológicas y económicas., O aumento do tráfego rodoviário durante as últimas décadas em combinação com a insuficiente manutenção levou à degradação acelerada das infraestruturas rodoviárias em vários países. Um método que se destaca na melhoria das propriedades das misturas betuminosas é a modificação do betume com polímeros. Embora a modificação de polímeros virgens cumpra esse objetivo, a modificação do betume com polímeros reciclados poderá apresentar um resultado equivalente na melhoria das propriedades do pavimento, desde que seja realizada uma adequada seleção dos polímeros, do betume e das condições de produção. A maior preocupação ambiental e o conhecido aumento do preço do petróleo, que influencia o preço do betume, aumentam o interesse em encontrar ligantes que substituam ou diminuíam a quantidade de betume na mistura betuminosa. Assim sendo, para além do estudo da modificação dos betumes com polímeros reciclados, também a substituição de 10% de betume por óleo usado de motor foi incluído neste estudo. Foram então produzidos ligantes modificados com polímeros virgens (SBS e EVA) e reciclados (EVAr e PEADr), com e sem substituição de 10 % do betume por óleo usado, os quais foram submetidos a uma série de ensaios tais como: ensaios de caracterização básica, de estabilidade ao armazenamento e de caracterização reológica, a partir dos quais foi possível concluir que a adição de ambos os materiais reciclados pode influenciar positivamente o desempenho do ligante acarretando vantagens ecológicas e económicas., Fundos FEDER através do Programa Operacional Fatores de Competitividade – COMPETE e por Fundos Nacionais através da FCT – Fundação para a Ciência e a Tecnologia no âmbito do projeto PLASTIROADS (PTDC/ECM/119179/2010) e do projeto estratégico UI 4047 – 2011-2012.

Currently there is a growing concern to minimize/conserve the natural resources used in road paving, as well as, the recovery of waste materials. As such, many studies have emerged where these issues, or part of them, are discussed. Under this assumption, the study of new binders that reduce the amount of bitumen, by adding waste, is essential for the sustainable development of the road paving industry. The main goal of this work is the development of an alternative bituminous binder with competitive performance. Thus, it aims at studying the addition of waste motor oil, waste high density polyethylene (HDPE) and styrene-butadiene-styrene (SBS) polymers into a conventional bitumen, in order to obtain a binder partially derived from waste, and at the same time, reducing the amount of bitumen used in the mixtures. According to the results obtained, it was concluded that the introduction of waste motor oil and polymers in the bitumen improves some properties, in particular an increase on the softening point. With regards to its influence on the mixtures performance, it was concluded that although the mixtures presented a lower stiffness modulus, they showed greater resistance to permanent deformation and fatigue and lower water sensitivity than the conventional mixture., FEDER funds through the Competitiveness Factors Operational Programme (COMPETE) and by national funds through the Portuguese Foundation for Science and Technology (FCT) in the scope of the PLASTIROAD Project (PTDC/ECM/119179/2010) and the Strategic Project UI 4047 – 2011-2012

With the increase in road traffic more demands are placed on pavements, and thus the structural and functional performance of road pavements needs to be improved. One method that can greatly improve the quality of the flexible pavements is the addition of polymers to the bitumen or to the asphalt mixtures. Although the modification of bitumen with virgin polymers can improve the properties of asphalt mixtures, the use of recycled plastic may also show a similar result with additional environmental advantages. This work aims to evaluate the possible advantages of modifying the bitumen with different plastic wastes, namely polyethylene (high density HDPE and low density LDPE), ethylene-vinyl acetate (EVA), acrylonitrile–butadiene-styrene (ABS) and crumb rubber, in order to improve the properties of the resulting binders for use in high performance asphalt mixtures. The performance of modified binders with recycled polymers was compared with that of the conventional bitumen and the one of a commercial modified binder (Styrelf). The results of the laboratory tests (basic characterization, dynamic viscosity, resilience and storage stability) will be used in the selection of the best plastic waste materials and production conditions that should be used in the modification of bitumen in order to optimize its behaviour, emphasizing that this study aims to promote the reuse of plastic waste in a more environmental and economic way., FEDER funds through the Operational competitiveness Programme – COMPETE and by National funds by FCT – Portuguese Foundation for Science and Technology in the scope of Project PTDC/ECM/119179/2010 and the Strategic Project - UI 4047 ‐ 2011‐2012

Com o aumento do tráfego rodoviário são colocadas maiores exigências aos pavimentos, surgindo a necessidade de melhorar o seu desempenho. Um método que pode melhorar significativamente a qualidade dos pavimentos flexíveis é a adição de polímeros aos ligantes/misturas betuminosas. Assim, foram produzidos ligantes modificados com polímeros reciclados, em diferentes condições, cujo desempenho foi comparado com o de ligantes convencionais e de um ligante modificado comercial. Os resultados dos ensaios laboratoriais serão utilizados na seleção de resíduos plásticos e das condições de produção do betume modificado para otimizar o seu comportamento, salientando-se que este estudo procura promover a reutilização de resíduos de uma forma mais ecológica e económica., Financiado por Fundos FEDER através do Programa Operacional Fatores de Competitividade – COMPETE e por Fundos Nacionais através da FCT – Fundação para a Ciência e a Tecnologia no âmbito do projeto PLASTIROADS (PTDC/ECM/119179/2010) e do projeto estratégico UI 4047 – 2011-2012.

The environmental and economic benefits of using Reclaimed Asphalt Pavement (RAP) material in hot mix asphalt (HMA) applications could be pushed up to the limit, by producing totally recycled HMAs (100% RAP), but the performance of this alternative must be satisfactory. In the present study, the utilization of a used motor oil as a rejuvenator was evaluated. This would allow the aged binder to restore some of its original properties, thus promoting an adequate performance of the mixture. After studying the RAP moisture content, the optimal amount of oil was determined by conventional bitumen tests, using the penetration grade as the selection criterion. Then, the binder was evaluated through rheological testing, and laboratory specimens were prepared and tested for water sensitivity, permanent deformation, stiffness and fatigue, in order to confirm that the totally recycled mixture will perform as good as a conventional mixture used for comparison purposes., Fundação para a Ciência e a Tecnologia (FCT)