10,615 research outputs found

    Nitrogen removal in a Sequencing Batch Biofilm Reactor : effect of carbon availability and intermittent aeration

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    This study aimed to investigate the effects of carbon availability and intermittent aeration on nitrogen removal in a Sequencing Batch Biofilm Reactor (SBBR). The percentage of nitrogen removal in the SBBRs operating with dump fill and slow fill with optimum intermittent aeration was quite similar, 75.7% and 69.2%, respectively, indicating that intermittent aeration allowed a considerable energy saving without compromising significantly nitrogen removal. Accumulation of storage polymers by heterotrophic bacteria was only observed in the dump fill mode of operation. FISH analyses of the biofilm indicated that ammonia-oxidisers belonged to the beta-subclass Proteobacteria and nitrite-oxidisers were affiliated with the genus Nitrospira.Fundo Europeu de Desenvolvimento Regional (FEDER)Fundação para a Ciência e a Tecnologia (FCT

    Effect of criteria weighting methods on the ranking of water suppliers’ performance

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    Water supply systems are a structural part of public utilities and as such are vital to the general well- being, public health, safe drinking water use, economic activities and environment protection. Being the water “market” a natural monopoly, regulation must, mainly, protect the interests of the user, based on a benchmarking strategy that promotes the quality of the water supply service and assuring the balance of the ruling tariffs. Due to the complexity of service quality assessment, the use of performance indicators is essential as a means to provide a measure the utility’s effectiveness and efficiency. In Portugal, this task is conducted by an independent public entity, which has defined a specific set of performance indicators. Currently, the adopted system does not provide a quantitative and integrated evaluation leading to an overall ranking of utilities’ performance and sustainability. This work aims to contribute to the improvement of the Portuguese assessment system, through the development of a complementary methodology that defines a global index of service quality (GISEQ) for a given water supply utility, based on a new application of multicriteria analysis. The GISEQ value is calculated as a combination of the normalized scores of each performance indicator, previously aggregated in three main groups: protection of user interests, sustainability of the utility and environmental sustainability. In this proposed methodology, each one of the selected performance indicators represents a criterion to be considered and judiciously weighted. An innovative approach to weights definition was performed as well as a sensitivity analysis of different weighting methods on water supply utilities’ ranking positions

    A global service quality index to evaluate the performance and sustainability in water supply utilities

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    Water supply systems are a structural part of public utilities and as such are vital to the general wellbeing, public health, safe drinking water use, economic activities and environment protection. The principal objective of regulation is to protect the interests of users by fostering quality in the services provided by utilities and ensuring a fair balance in the charges levied, guaranteeing the essentiality, equity, indispensability, feasibility and cost-effectiveness principles. The use of performance indicators is widely recommended as a measure of the utility’s effectiveness and efficiency. In Portugal, the regulation of service quality is conducted by ERSAR (Portuguese Authority for the Regulation of Water and Waste), which has decided to define its own set of performance indicators that is less comprehensive than those adopted by the IWA (International Water Association). Currently, the adopted system does not provide a quantitative and integrated evaluation leading to an overall ranking of utilities’ performance and sustainability. The aim of this paper is to contribute for the improvement of the Portuguese performance assessment system, through the development and application of a complementary methodology to define a global index of service quality (GISEQ) for a given water supplier in order to achieve accurate performance rates. This methodology allows a truly quantitative evaluation in which each performance indicator represents a criterion to be considered and judiciously weighted, based on the results of an on-line questionnaire proposed to a selected set of academic and professional experts. The GISEQ values are calculated as a weighted linear combination of the normalised scores of each performance indicator, which is one of the most common aggregation procedures available in the context of multicriteria evaluation. The criteria normalisation process essentially based on fuzzy sets defined for each indicator, considering the established ERSAR or legislation standards. An innovative approach to weights definition was also performed as well as a sensitivity analysis of GISEQ values to different weighting methods.(undefined

    Distribuição espacial de fósforo num latossolo que recebeu iodo de esgoto e adubação mineral e sua relação com outros atributos químicos.

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    O cálculo da quantidade do lodo de esgoto para aplicação no solo em função da quantidade de N necessária para o desenvolvimento das culturas pode alterar o comportamento do fósforo (P) em virtude de sua acumulação no solo. O objetivo deste trabalho foi avaliar a distribuição espacial do P num Latossolo cultivado com milho, onde foram feitas seis aplicações anuais de lodo de esgoto (LE) em comparação à adubação mineral (AM). Realizou-se uma amostragem sistemática nos dois tratamentos no final do ciclo da cultura. Nestas amostras, foram determinados os teores de P-Resina, P-Mehlich I, matéria orgânica (MO), acidez potencial (H+Al), potássio (K), cálcio (Ca) e magnésio (Mg) bem como calculados os valores de soma de bases (SB), capacidade de troca catiônica (CTC) e saturação por bases (V%). Em LE observou-se distribuição aleatória do P na parcela contrastando com o tratamento AM que apresentou as maiores concentrações desse nutriente na parte inferior do talhão. O P esteve mais correlacionado com a matéria orgânica do que com quaisquer dos outros atributos químicos estudados

    Hematologic toxicity of radium-223 in elderly patients with metastatic Castration Resistant Prostate Cancer: a real-life experience

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    Background: Treatment with radium-223 has been shown to increase survival and to delay skeletal events related to bone metastases of patients with metastatic Castration Resistant Prostate Cancer (mCRPC). This treatment has also proved to be well tolerated, and hematological toxicity, in particular anemia, represents the most represented adverse event. Materials and methods: We evaluated the hematologic toxicity of Ra-223 treatment in a real-life experience of 38 patients from two Italian cancer centers, with bone metastases from mCRPC. The main endpoint of the study was the evaluation of the efficacy and tolerability of treatment with radium-223, with greater reference to hematological toxicity (especially anemia) as the cause of interruption of treatment, specifically in the elderly patient. Results: From August 2016 to October 2017, a total of 38 consecutive nonselected patients, 20 of them aged >75 years, with mCRPC symptomatic bone metastases, were enrolled for radium-223 at standard doses. Hematologic adverse events were recorded more frequently (72.4% with AE), and 36.8% had anemia. The most frequent cause of treatment discontinuation due to AEs was anemia [8/10 patients (80%)], followed by thrombocytopenia (2 patients) and neutropenia (1 patient). Hematologic AEs were more represented in elderly patients with greater disease burden and previously treated with docetaxel. Conclusions: Anemia is the most represented AE related to radium-223 treatment in elderly patients with greater disease burden and previously treated with docetaxel, besides representing the main reason for interruption of treatment. Correct patient selection, appropriate timing, and adequate supportive care are elements that could facilitate successful treatment with radium-223, preventing premature interruption of the same. The results of this experience support the opportunity to propose treatment with radium-223 mostly in patients in the earliest stages

    Cultura em substratos orgânicos de Gerberas

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    O cultivo sem solo de Gerbera (Gerbera jamesonii) tem-se revelado uma técnica adequada, permitindo ultrapassar alguns dos problemas surgidos na cultura tradicional, em solo. No âmbito do Projecto Agro no197 “Cultura sem solo com reutilização do efluente, em estufa com controle ambiental melhorado”, desenvolvido pela Direcçao Regional de Agricultura do Algarve, pelo Cento de Hidroponia e Utilidades Hortofrutícolas e pela Universidade do Algarve testou-se o cultivo de gerbera em substratos alternativos, no Centro de Experimentação Hortofrutícola do Patacão. Cultivaram-se quatro cultivares de gerbera: Monika, Junkfrau, Venice e Lady, em substratos preparados à base de resíduos orgânicos: casca de pinho e bagaço de uva, durante dois anos consecutivos. Os resultados obtidos sugerem que os substratos testados apresentam características adequadas à cultura da gerbera, tendo-se obtido as produções mais elevadas com o bagaço de uva compostado e a casca de pinho não compostada. Das cv. em estudo, no 1o ano a Venice apresentou o maior número de flores comercializáveis, seguida da Lady com mais flores na classe Extra. No 2o ano, a produção foi mais equilibrada entre as cultivares, sendo de registar o aumento da produção em duas cv., Junkfrau e Monica
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