Closed rotating biological contactors in nitrate removal : operating parameters and biofilm efficiency

Rotating Biological Contactors (RBC) constitute a very unique and superior alternative for biodegradable matter and nitrogen removal on account of their feasibility, simplicity of design and operation, short start-up, low land area requirement, low energy consumption, low operating and maintenance cost and treatment efficiency, as well as easy scalability. A new generation of RBC, working in anoxic conditions (closed/AnRBC) has been developed, mainly for nitrate removal. Operating parameters like C/N ratio, phosphorous concentration, organic and hydraulic loading rates and retention time, directly affect biofilm efficiency. The effect of these parameters on nitrate removal efficiency will be focused herein

Biofilmes, na indústria e na saúde

[Excerto] As células microbianas aderem firmemente a quase todas as superfícies imersas em soluções aquosas. As células assim imobilizadas crescem, reproduzem-se e produzem substâncias poliméricas extracelulares, que se estendem para além da superfície das células, formando um emaranhado polimérico que envolve toda a biomassa aderida, assumindo o conjunto a designação de biofilme. (...

Physico-chemical aspects of adhesion

Adhesion of microorganisms to solid surfaces is one of the prime steps in the formation of biofilms. (...

Landscape character assessment and regional landscape strategy in the Azores, Portugal

Fast and continuous landscape changes have been considered as one of the strongest drivers behind the loss of nature values, along with degradation and regimes of ecological disturbances that have evident impacts on economic activities ( Olarieta et al., 2008 ; Nuissl et al., 2009 ). The need to preserve the diversity, identity and cultural heritage of landscapes and societal demand for sustainable development ( Roca and Oliveira-Roca, 2007 ; van Eetvelde and Antrop, 2009a ) has led to initiatives for inventorying, assessing and monitoring landscape dynamics (Meeus, 1995; Swanwick, 2002 ; Cancela d’Abreu et al., 2005 ). It has also improved landscape modelling based on future scenarios ( van Berkel and Verburg, 2011 ).info:eu-repo/semantics/publishedVersio

Planning the Green Infrastructure of the Tagus River Estuary in Lisbon Metropolitan Area, Portugal

The Tagus River is the most important and largest watershed of Iberia, with 1007 km long and 81 000 km2 basin, about 30% Portuguese. Understood in a cross-border perspective, it constitutes a valuable resource that brings together relevant biophysical, historical and cultural aspects translated into a huge richness and landscape diversity. The Tagus estuary is the largest wetland area in Portugal and one of the most important in Europe, with an area of 325 km2 and a high status for the conservation of important biodiversity. This estuary corresponds to the core of the Lisbon Metropolitan Area, which is about 3.3% of the national territory and population of roughly 3 million inhabitants. The Landscape Observatory of the Tagus River (LOT) is a coordination structure and dynamics of the Tagus Cultural Landscape project, covering the national section of the river and the surrounding landscape. The LOT aims to promote and safeguard the diversity and excellence of the cultural Tagus landscape through its study, the collection, exchange and systematization of information and the establishment of protocols and partnerships between public institutions and local communities in a territorial governance approach (http://obspaisagemtejo.org) (Oliveira et al., 2014). The ultimate goal is to build a bottom-up process that would culminate, in the near future, on the nomination of the Tagus’s Cultural Landscape to the UNESCO. The proposal for its inclusion on the Portuguese indicative list has already been presented to the UNESCO National Commission. One of the on-going projects is the planning of a Green Infrastructure (GI)along the whole Portuguese river, understood as an instrument designed toachieve ecological and social benefits to be considered on spatial managementfrom a territorial cohesion point of view. Currently, ecological networks inEurope are understood as fundamental to territorial development through themultifunctional use of natural capital. Ecological networks should beconsidered as infrastructures that ensure the circulation of flows, energy andproducts as essential to a balanced development with relevant dynamicsbetween the urban and rural areas. An ecological network is designed to ensurein each area maintenance, functionality and sustainability of biophysicalsystems (water cycle, carbon, nitrogen), ensuring in this way, the quality anddiversity of species, habitats, the ecosystems and landscapes. This project ha

Landscape perception as a basis for landscape strategies. Developments in Portugal

The perception of landscape and its transformation underpins the process of socio-ecological awareness that is essential to a healthy relationship between Humans and Nature. One of the great challenges to contemporary and future society is the vital need to increase knowledge and awareness of the development model that has led us to the global ecological crisis that we face today. We know that resources may become scarce if we continue to consume them at the current rate, especially if the rise in atmospheric temperature exceeds certain limits. The landscape reflects this economic model and the decisions that are taken on the territory. Different expressions may be used depending on the scale and intensity of the transformation that has occurred as the landscape is a resource that is essential not only to the development of economic activities but also to the qualification of the territory and the well-being of the population (Cassatella and Peano, 2011). In Portugal, the result of two critical trends can be observed in the landscape - the depopulation of rural areas with the consequent concentration of population in urban settlements influenced by the coastline, and the inevitable simplification of the agricultural and forest cultural mosaics.info:eu-repo/semantics/publishedVersio

Conceptualizing sexual and gender-based violence in European asylum reception centers

Background: Sexual and gender based violence (SGBV) is a major public health problem and a violation of human rights. Refugees, asylum seekers and migrants are exposed to a constant risk for both victimization and perpetration. Yet, in the context of European asylum reception centers (EARF) professionals are also considered to be at risk. Our study explores the conceptualization of SGBV that residents and professionals have in this specific context. Further, we intent to identify key socio-demographic characteristics that are associated with SGBV conceptualization for both groups. Methods: We developed a cross-sectional study using the Senperforto project database. Semi-structured interviews were conducted with residents (n=398) and professionals (n=202) at EARF. A principal component analysis (PCA) was conducted to variables related with knowledge on SGBV. Chi-square test and Fisher's exact test were applied to understand if significant statistical association exists with socio-demographic characteristics (significant level 0.5%). Results: The majority of residents were male (64.6%), aged from 19 to 29years (41.4%) and single (66.8%); for professionals the majority were women (56.2%), aged from 30 to 39years (42.3%) and married (56.8%). PCA for residents resulted in 14 dimensions of SGBV representing 83.56% of the total variance of the data, while for professionals it resulted in 17 dimensions that represent 86.92% of the total variance of the data. For both groups differences in SGBV conceptualization were found according to host country, sex, age and marital status. Specific for residents we found differences according to the time of arrival to Europe/host country and type of accommodation, while for professionals differences were found according to legal status and education skills. Conclusion: Residents and professionals described different conceptualization of SGBV, with specific types of SGBV not being recognized as a violent act. Primary preventive strategies in EARF should focus on reducing SGBV conceptualization discrepancies, taking into account socio-demographic characteristics

The role of exopolymers in Sphingomonas paucimobilis attachment and biofilm formation

Exopolymers have an important role in biofilm formation, being involved in the initial adhesion events and influencing the biofilm characteristics. The results of a study with a strain of Sphingomonas paucimobilis that excretes a polysaccharide gum (gellan) has been used to exemplify the role of exopolymers in cell attachement and biofilm formation. The attachement results were interpreted throught the XDLVO theory and they revealed that exopolymers have a dual role in cell attachement by booth coating the substratum making adhesion favourable and by strengthing adeshion through the establishement of polymeric bridges. Exopolymers were also essential to the formation of Sphingomonas paucimobilis biofilms acting as scaffolds for bacterial proliferation. The physicochemical properties, the composition of the biofilm matrix and the cohesion forces within the biofilm were also conditioned by the presence of exopolymers