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- Considerations on the monitoring of water quality in urban streams: a case study in PortugalPublication . Guerreiro, Maria João; Abreu, Isabel; Monteiro, Álvaro; Jesus, Teresa Maria Gonçalves Moreira de; Fonseca, AnaMonitoring water quality in urban stream is of utmost importance for water resources managers, who are pressured to optimize monitoring schemes in order to reduce costs. The present study aims to use the results of a 2-year-long water quality monitoring pro- gram of an urban stream in Portugal to identify improve- ment opportunities. The urban stream under study was subjected to wastewater treatment plants effluent dis- charges, leachates from a major sealed landfill, low- class housing effluents, and nonpoint sources of pollu- tion. Contributing watersheds are mostly artificial sur- faces and agricultural land, which irrigate directly from the river. River water quality was evaluated on 11 sam- pling locations for 24 months from October 2013 to September 2015. The present paper describes statistical analysis of the results obtained for 12 physicochemical parameters in order to optimize the monitoring scheme. Cluster analysis detected a seasonal variation in the water quality and a spatial pattern based on the major point sources of pollution. A factor analysis showed that the parameters that mostly contribute to water quality assessment in this urban river are alkalinity, ammonia, electrical conductivity, pH, temperature, and dissolved oxygen. Results suggest that the monitoring efforts— and associated costs—may be reduced by decreasing monitoring frequency, sampling points, and monitored parameters. The statistical analysis described in this study may be replicated in other water quality monitor- ing programs, providing useful and important informa- tion for the systematic and iterative assessment of the adequacy of water quality sampling programs towards a sustainable management of water quality surveillance.
- Perception of Portuguese and Brazilian dentists regarding the importance of teeth and dental materials after exposure to high temperatures: forensics perspectivePublication . Ramos, Beatriz; Abreu, Isabel; Moreira, Teresa; Silveira, Augusta; Lopes Cardoso, Inês; Guimarães, Maria Inês; Mele, Federica; Santoro, ValeriaBackground: The main objective of this study was to carry out an online questionnaire in order to assess dentists’ knowledge and perception of dental materials submitted to high temperatures, helping to clarify and raise awareness of possible gaps in the area of forensic dentistry, especially in human identification. Results: Out of a total of 272 respondents, there was a greater influx of responses from countries such as Portugal and Brazil, the majority being female (66.3%), with an average age of 39 years. Most dentists consider complete clinical records to be extremely important. In addition, professionals with less experience provide fewer models in releasing their clinical records. In the case of dental materials, dentists consider composite resin and glass ionomers to be more susceptible to changes in shape and colour, while amalgam is considered the most stable, followed by ceramic and metal-ceramic crowns. On the other hand, dentin is considered more susceptible to colour changes than enamel. Enamel is seen by most professionals as resistant, undergoing few changes in shape at high temperatures. Conclusions: The opinion of the surveyed dentists on this subject is broadly in line with the existing literature. The only observed differences were related to exposure time and enamel resistance, since they assume that enamel is more resistant, and dentin is more vulnerable.