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Nanoparticles are key components underlying recent technological advances in various industrial and medical fields, and thus understanding their mode of interaction with biological systems is essential., Nanoparticles are key components underlying recent technological advances in various industrial and medical fields, and thus understanding their mode of interaction with biological systems is essential. However, while several nanoparticle systems have been shown to interact with blood platelets, many questions remain concerning the mechanisms of platelet activation and the role that the physicochemical properties of nanoparticles play in inducing platelet aggregation. Here, using negatively charged polystyrene nanoparticles with sizes of 25, 50, 119, 151, 201 nm and negatively charged platinum nanoparticles with sizes of 7 and 73 nm, we show that it is not the size of the nanoparticles but rather the nanoparticle surface area that is critical in mediating the effects on platelet activation. The nanoparticles stimulate platelet aggregation through passive (agglutination) and activation of integrin αIIbβ3 through a pathway regulated by Src and Syk tyrosine kinase.

The development of stimuli-responsive interfaces between synthetic materials and biological systems is providing the unprecedented ability to modulate biomolecular interactions for a diverse range of biotechnological and biomedical applications. Antibody–antigen binding interactions are at the heart of many biosensing platforms, but no attempts have been made yet to control antibody–antigen binding in an on-demand fashion. Herein, a molecular surface was designed and developed that utilizes an electric potential to drive a conformational change in surface bound peptide moiety, to give on-demand control over antigen–antibody interactions on sensor chips. The molecularly engineered surfaces allow for propagation of conformational changes from the molecular switching unit to a distal progesterone antigen, resulting in promotion (ON state) or inhibition (OFF state) of progesterone antibody binding. The approach presented here can be generally applicable to other antigen–antibody systems and meets the technological needs for in situ long-term assessment of biological processes and disease monitoring on-demand.

Gold surfaces were molecularly tailored with a saccharide binding motif capable of covalently adhering cells. This facilitated communication via the macrophage membrane with implications for understanding mammalian cell signalling., The fabrication of a molecularly tailored surface functionalised with a saccharide binding motif, a phenyl boronic acid derivative is reported. The functionalised surface facilitated the transfer of electrons, via unique electronic interactions mediated by the presence of the boronic acid, from a macrophage cell line. This is the first example of eukaryotic cellular-electrical communication mediated by the binding of cells via their cell–surface saccharide units.

Due to highly heterogeneous edaphoclimatic features, Iberian Southwest Mountains are a major laboratory for essays on biogeography, concerning Atlantic remnant vegetation. Following a decade of PhD fieldwork in Serrano-Monchiquense District, namely facing West Iberian and Portuguese Divisorian Sub-Provinces, this work intends to clarify and propose new typologies for the Potential Natural Vegetation of these territories and consequently accurately update its biogeographic boundaries. Additionally, we address all serial and catenal features regarding climatophile and edaphophile vegetation series, with major updates for taxonomic and syntaxonomic issues, which gives a solid phytocoenotic uniqueness to this territory. Using phytosociological methodology, we studied climatophilous and edaphophile serial dynamics, featuring perennial vegetation. We discuss 12 sintaxa at association and subassociation levels, adding a discriminatory analysis of all biogeographic features from Serrano Monchiquense District, describing its different County’s in a comparative framework with neighbor Districts. We propose a synthetic map, resuming the analyzed information, where we stablish new and more accurate borders to the biogeographic map of Southern Portugal. This work, its a final and exhaustive description where is related all major biogeographic inferences that matter to be highlighted in the scope of Southwest Iberian Peninsula, concerning the border between two major biogeographic Provinces, revisiting all phytocoenotic conservation issues., Disclaimer: This is the original version, which not includes the co-authors new inputs to the generated maps, is being updated and will be published in future versions.

A hierarchical bottom-up route exploiting reversible covalent interactions with boronic acids and so-called click chemistry for selective glycoprotein detection is described. The self-assembled and imprinted surfaces confer high binding affinities, nanomolar sensitivity, exceptional glycoprotein specificity and selectivity., Many glycoproteins are intimately linked to the onset and progression of numerous heritable or acquired diseases of humans, including cancer. Indeed the recognition of specific glycoproteins remains a significant challenge in analytical method and diagnostic development. Herein, a hierarchical bottom-up route exploiting reversible covalent interactions with boronic acids and so-called click chemistry for the fabrication of glycoprotein selective surfaces that surmount current antibody constraints is described. The self-assembled and imprinted surfaces, containing specific glycoprotein molecular recognition nanocavities, confer high binding affinities, nanomolar sensitivity, exceptional glycoprotein specificity and selectivity with as high as 30 fold selectivity for prostate specific antigen (PSA) over other glycoproteins. This synthetic, robust and highly selective recognition platform can be used in complex biological media and be recycled multiple times with no performance decrement.

Electrically switchable surfaces based on oligopeptides are ubiquitous in both switching specific protein interactions in highly fouling media while still offering the non-specific protein-resistance to the surface., Herein, electrically switchable mixed self-assembled monolayers based on oligopeptides have been developed and investigated for their suitability in achieving control over biomolecular interactions in the presence of complex biological conditions. Our model system, a biotinylated oligopeptide tethered to gold within a background of tri(ethylene glycol) undecanethiol, is ubiquitous in both switching specific protein interactions in highly fouling media while still offering the non-specific protein-resistance to the surface. Furthermore, the work demonstrated that the performance of the switching on the electro-switchable oligopeptide is sensitive to the characteristics of the media, and in particular, its protein concentration and buffer composition, and thus such aspects should be considered and addressed to assure maximum switching performance. This study lays the foundation for developing more realistic dynamic extracellular matrix models and is certainly applicable in a wide variety of biological and medical applications.

Gold is a standard surface for attachment of thiol-based self-assembled monolayers (SAMs). To achieve uniform defect free SAM coatings, which are essential for bio/chemical sensing applications, the gold surface must have low roughness, and be highly orientated. These requirements are normally achieved by either heating during Au deposition or post deposition Au surface annealing. This paper shows that room temperature deposited gold, can afford equivalent gold surfaces, if the gold deposition parameters are carefully controlled. This observation is an important result as heating (or annealing) of the deposited gold can have a detrimental effect on the mechanical properties of the silicon on which the gold is deposited used in microsensors. The paper presents the investigation of the morphology and crystalline structure of Au film prepared by thermal evaporation at room temperature on silicon. The effect of gold deposition rate is studied, and it is shown that by increasing the deposition rate from 0.02 nm s-1 to 0.14 nm s-1 the gold surface RMS roughness decreases, whereas the grain size of the deposited gold is seen to follow a step function decreasing suddenly between 0.06 and 0.10 nm s-1. The XRD intensity of the preferentially [111] orientated gold crystallites is also seen to increase as the deposition rate increases up to a deposition rate of 0.14 nm s-1. Formation and characterization of 1-dodecanethiol on these Au coated samples is also studied using contact angle. It is shown that by increasing the Au deposition rate the contact angle hysteresis (CAH) decreases until it plateaus, for a deposition rate greater than 0.14 nm s-1, where the CAH is smaller than 9 degrees which is an indication of homogeneous SAM formation, on a smooth surface.

Our ability to tailor the electronic properties of surfaces by nanomodification is paramount for various applications, including development of sensing, fuel cell, and solar technologies. Moreover, in order to improve the rational design of conducting surfaces, an improved understanding of structure/function relationships of nanomodifications and effect they have on the underlying electronic properties is required. Herein, we report on the tuning and optimization of the electrochemical properties of indium tin oxide (ITO) functionalized with single-walled carbon nanotubes (SWCNTs). This was achieved by controlling in situ grafting of aryl amine diazonium films on the nanoscale which were used to covalently tether SWCNTs. The structure/function relationship of these nanomodifications on the electronic properties of ITO was elucidated via time-of-flight secondary ion mass spectrometry and electrochemical and physical characterization techniques which has led to new mechanistic insights into the in situ grafting of diazonium. We discovered that the connecting bond is a nitro group which is covalently linked to a carbon on the aryl amine. The increased understanding of the surface chemistry gained through these studies enabled us to fabricate surfaces with optimized electron transfer kinetics. The knowledge gained from these studies allows for the rational design and tuning of the electronic properties of ITO-based conducting surfaces important for development of various electronic applications.

CBiOS Science Sessions - 2013 - Nutrition: pregnancy counselling website (http://nutricao.ulusofona.pt) Nutrição: website de aconselhamento durante a gravidez, Nelson Alexandre Rodrigues Tavares; Relationship between daily water intake and skin physiology, Impacto Cutâneo do consumo dietário de água, Maria Lídia Laginha Mestre Guerreiro da Palma; Development of different types of nanosystems: polymeric, lipid-based and metallic nanoparticles. Desenvolvimento de diferentes tipos de nanosistemas: poliméricos, lipid-based e de nanoparticulas metálicas, Catarina Silva, Patrícia Rijo, Catarina Reis; Interaction between propofol and HES 130/0.4: Chemical, physiological and toxicological. Interação entre Propofol e HES 130/0.4: Química, Fisiológica e Toxicológica, Aura Silva, Ana Ortiz, Carlos Venâncio, Rui Silva, Joaquim Mendes, Paula Guedes, Helena Vala, David Ferreira; Study the potential applicability of the by-products of the Prunus cerasus in promoting health and skin care. Estudo da aplicabilidade dos sub-produtos de Prunus cerasus na promoção de saúde cutânea, Elisabete Maurício, Catarina Rosado, Diaz Diaz Lanza; Cell migration and adhesion - impact of ROS in tumour metastasis Migração celular e adesão - impacto de ROS na metástase tumural, Nuno Saraiva; Bioactive and Non-Conventional Photoprotection Fotoproteção Bioactiva e Não-Convencional, André Rolim Baby.

Following PhD thesis work surveys on Monchiquense District, the presence of Quercus estremadurensis O. Schwarz was noticed in the catenal dynamics of Avenello strictae-Quercetum marianicae woodlands, ecologically related to freatic and temporihygrophilous positions. Thenceforth, it has been re-discovered, trough fieldwork and Herbaria research, in several biogeographic territories, namely in the Southwestern and Western part of Iberian Peninsula, following the border between Eurosiberian and Mediterranean macrobioclima-tes, as well as in relictual groves of semi-deciduous woodlands, in humid and hyperoceanic areas. Here, we combine the phytosociological methodology with species distribution modelling (SDMs) to clarify the sintaxonomic affiliation of these rare formations, and to present a spatially-explicit model for its potential distribution. BIOMOD2 ensemble modelling framework was implemented to build Q. estremadurensis potential distribution in the Iberian Peninsula, considering climate, slope, land use and soil, as ecologically relevant determinants, for the species distribution. In the lack of absence data, pseudo-absences have been randomly selected from the studied area excluding available presence points. The predictive performance per variable was assessed using a randomization procedure as implemented in BIOMOD2. Being present in several biogeographic territories, from Portuguese-Divisorian and Algarvian-Monchiquense Sub-Provinces, passing through Luso-Extremadurean and Carpetanan-Leonese ones, we analyze four possible syntaxons occurring in the frame of Quercion broteroi and Aceri granatensis-Quercion fagineae, deeply related to the biogeographic territories where they occur . Ecologically prone to streams and deep valleys, normally in the midst of Pruno-Rubion dense thorn-bushes, mature and pure woodlands are totally absent in all studied territories, due the heavy landscape transformation, which made this study and interpretation of these formations hard and tricky. Also, in the absence of phylogeographic and molecular essays, relating the independence or infra-specific range of Quercus estremadurensis O. Schwarz, inside the broad sense of Quercus robur L., this taxon faces great menace, mainly by introgression features with broad sense Quercus faginea Lam., Q. marianica C. Vicioso / Q. canariensis Willd. and also Q. pyrenaica Willd., Disclaimer: The presented PDF, has updated nomenclatural issues, linked with oak (Quercus L.) taxonomy and forest syntaxonomy in Southern Portugal, namely related with Campanulo alatae-Quercetum estremadurensis ass. nova, which autorship belongs to the present authors, but has been unethically plagiated by colleagues.

O conceito de Vegetação Natural Potencial (VNP) e a sua representação cartográfica assume uma importância primordial para a maioria dos países europeus nas questões relacionadas com o restauro de habitats. Dada a relação existente entre as séries de vegetação de um território e os factores ambientais, este artigo visa o desenvolvimento de modelação predictiva da VNP para o concelho de Loures (AML). Atendendo à possibilidade de integração de um vasto conhecimento empírico, utilizou-se uma abordagem de modelação precedida de classificação de séries de vegetação (classification-then-modelling). Para averiguar a relação entre 6 séries de vegetação e um conjunto de 8 variáveis ambientais recorreu-se a Modelos de Distribuição de Espécies (SDM) aplicados ao nível da comunidade, suportados em Sistemas de Informação Geográfica (SIG) e em modelos de regressão, machine learning e rule-based. Os resultados obtidos permitiram aferir o modo como os gradientes ecológicos determinam a ocorrência das séries de vegetação. A cartografia predictiva da VNP resultante do modelo da Máxima Entropia, foi ainda validada com a cartografia oficial da VNP do concelho de Loures (precisão global de 88%). Dado que a gestão e conservação da biodiversidade é frequentemente desenvolvida a escalas de grande detalhe, o SDM possibilita a integração de observações directas de comunidades vegetais, e uma interpretação da distribuição local da VNP ao longo de gradientes ambientais., The concept of Potential Natural Vegetation (PNV) and its mapping have become extremely important within the scope of habitat restoration in almost every European country. The aim of this study is to predict the PNV in Loures based on the vegetation series and the main environmental variables. The modelling approach is based on the distribution of communities referred to as classification-thenmodelling. Subsequently, several statistical model-fitting techniques, such as regression models, machine learning and rule-based, were successfully applied to the survey data (vegetation series; and 8 environmental/predictor variables). The spatial database was organized as a Geographic Information System (GIS) and was also used to perform the Species Distribution Models (SDM) at community level. The results show a high correspondence between the vegetation series and the environmental gradients. The predicted PNV maps based on the Maximum Entropy Model were validated with the official map of the PNV of Loures, and presented an overall accuracy of 88%. Often, conservation planning and biodiversity resource management is carried out at more detailed scales, where SDM allows integration of community direct observations and improve our interpretation of PNV local distributions along environmental gradients., Le concept de Végétation Naturelle Potentielle (VNP) et sa représentation cartographique ont une importance primordiale dans la plupart des États européens, quand il s’agit de restaurer des habitats. En prenant en compte le rapport existant entre les séries de végétation et les facteurs ambientaux du territoire, on a cherché une modélisation prédictive de la VNP du concelho de Loures (AML). Tout en intégrant une importante connaissance empirique, on a introduit dans ce modèle une classification des séries de végétation (classification-then-modelling). Pour établir la relation existant entre 6 séries de végétation et 8 variables ambientales, on a eu recours à des Modèles de Distribution des Espèces (SDM), applicables au niveau des communautés en Systèmes d’Information Géographique (SIG) et en modèle de régression, machine learning et rule-based. Les résultats montrent comment les gradients écologiques déterminent les séries de végétation. La cartographie prédictive de la VNP, selon le modèle d’Enthropie Maximale, a ainsi été validée à 88 % par rapport à la cartographie officielle de la VNP du concelho de Loures. Étant donné que la gestion et conservation de la biodiversité sont souvent pratiquées à des échelles de grand détail, le SDM permet d’intégrer les observations directes de communautés végétales et l’interprétation de la répartition locale de la VNP au long de gradients ambientaux.

Introduction: The α-lipoic acid (ALA) has been used as a treatment to reduce oxidative damage in Systemic Arterial Hypertension (SAH), but there are no in vivo studies reporting the effect of its mechanism of action on iron metabolism. Objective: To evaluate the antioxidant effect of α-lipoic acid on Blood cell count (CBC) and iron metabolism in hypertensive subjects with or without anemia. Method: Double-blind, randomized, placebo-controlled clinical trial. The sample consisted of 60 hypertensive patients that were randomly divided into treatment group (n = 32), receiving 600 mg / day of ALA for twelve weeks and control group (n = 28), receiving placebo for the same period. Blood cell count, serum iron, ferritin, Latent Iron-Binding Capacity (LIBC), Total Iron-Binding Capacity (TIBC), Transferrin Saturation Index (TSI) and transferrin were assessed before and after intervention. To assess changes between groups, the Student t-test and ANOVA were used, adopting a significance level of 5%. Results: After intervention, ALA supplementation showed a statistically significant (p < 0.05) association with the reduction of total leukocytes, increase in the number of neutrophils and reductions in the serum levels of iron and TSI. Conclusion: Oral administration of ALA as a therapeutic adjuvant changes the hematologic response of white blood cells and reduces the absorption of iron. It is observed that the mechanism of metals chelation by lipoic acid may be responsible for these changes and, consequently, could trigger a condition of iron deficiency anemia in hypertensive individuals. Introducción: El Ácido α-Lipóico (ALA) ha sido utilizado como recurso terapéutico para reducir daño oxidativo en la Hipertensión Arterial Sistémica (HAS), pero aún no existen estudios in vivo que reporten sobre su mecanismo de acción en el metabolismo del hierro. Objetivo: Evaluar el efecto antioxidante del ácido Alfa-Lipóico sobre el hemograma y metabolismo del hierro en individuos hipertensos con o sin anemia. Métodos: Estudio clínico doble-ciego, randomizado y controlado con placebo. La muestra fue constituida por 60 individuos hipertensos, distribuidos aleatoriamente en grupo tratamiento (n = 32), que recibió 600 mg/día del ALA por doce semanas y grupo control (n = 28), que recibió el placebo por el mismo período. Fueron analizados antes y después de la intervención, los parámetros del hemograma, Hierro Sérico, Ferritina, Capacidad Latente de Enlace del hierro, Capacidad Total de Enlace del Hierro, Índice de Saturación de la Transferrina (ISI) y Transferrina. Para evaluar las alteraciones entre los grupos, se utilizó el teste t de Student y el análisis de varianza ANOVA, adoptándose el nivel de significación de 5%. Resultados: Después de la intervención, el suplemento con el ALA demostró una asociación estadísticamente significativa (p < 0,05) con la reducción de los leucocitos totales, aumento del número de neutrófilos y reducciones en los niveles de Hierro Sérico e ISI. Conclusión: La administración oral del ALA como un adyuvante terapéutico, altera la respuesta hematológica del leucograma y reduce la absorción del hierro. Cabe señalar que el mecanismo de quelación de metales por el ácido lipoico puede ser responsable de estos cambios y, en consecuencia, podría desencadenar una condición de anemia ferropénica en individuos hipertensos.

Vegetation is an important part of landscape heritage valuation since it can be not only valuated per se but also as habitat for many wildlife species. Since some years, the authors develop methods to estimate the landscape natural and cultural heritage values. A method to estimate vegetation heritage value is explained in this study being applied to Central Alentejo. A criteria selection and weighting method is presented as well as the evaluation established by a round table of experts. The criteria used were: potential area for vegetation conservation purposes based on horizontal and vertical structure of vegetation patches, tree density, rare species richness, phytocoenotic maturity, importance as ecological corridor, historical record, scientific and educational potential and recreation potential. The vegetation heritage value was calculated by a linear combination of the weighted criteria.

Understanding the dynamic behavior of switchable surfaces is of paramount importance for the development of controllable and tailor-made surface materials. Herein, electrically switchable mixed self-assembled monolayers based on oligopeptides have been investigated in order to elucidate their conformational mechanism and structural requirements for the regulation of biomolecular interactions between proteins and ligands appended to the end of surface tethered oligopeptides. The interaction of the neutravidin protein to a surface appended biotin ligand was chosen as a model system. All the considerable experimental data, taken together with detailed computational work, support a switching mechanism in which biomolecular interactions are controlled by conformational changes between fully extended (“ON” state) and collapsed (“OFF” state) oligopeptide conformer structures. In the fully extended conformation, the biotin appended to the oligopeptide is largely free from steric factors allowing it to efficiently bind to the neutravidin from solution. While under a collapsed conformation, the ligand presented at the surface is partially embedded in the second component of the mixed SAM, and thus sterically shielded and inaccessible for neutravidin binding. Steric hindrances aroused from the neighboring surface-confined oligopeptide chains exert a great influence over the conformational behaviour of the oligopeptides, and as a consequence, over the switching efficiency. Our results also highlight the role of oligopeptide length in controlling binding switching efficiency. This study lays the foundation for designing and constructing dynamic surface materials with novel biological functions and capabilities, enabling their utilization in a wide variety of biological and medical applications.

OBJECTIVES: cigarette smoking has been the modifiable risk factor most consistently associated with earlier menopause. This preliminary study based on cross-sectional data aimed to analyze the association between smoking status and age of onset of menopause in a Brazilian population. METHODS: a cross-sectional study was carried out with 1,222 female employees of Rio de Janeiro university campuses aged over 35 years who were at risk of natural menopause. A Cox proportional hazards model was used to investigate the association between smoking status and age at the onset of menopause, adjusting for education, parity and alcohol consumption. RESULTS: current smokers showed a 56% increase in the risk of menopause, being 1.8 years younger at menopause onset compared with women who had never smoked. However, no differences were observed between former smokers and women who had never smoked. The adjusted median age at menopause was 49.5 years for current smokers and 51.3 years for women who had never smoked (p

As result of several field trips following PhD researches in Marianic-Monchiquensean Sector, we describe a new broomland association named Genistetum triachanthi-polyanthi as a thermomediterranean, oceanic and sub-humid to humid, schistose association. The 26 relevés analysis, combining phytosociologic methodology with hierarchical cluster analysis (Ward's Hierarchical Clustering, based on Bray-Curtis distance) allowed the segregation of this Monchiquense association. Appearing as a regressive stage, or fringe, of secondary or edaphoxerophilous cork oak and, punctually, holm oak woodlands, it reveals a high sinecological value, in a wide variety of edaphoclimatic typologies, despite its poorest species number, since it includes restrict distribution taxa with high conservational value. At last, sintaxonomic issues are highlighted as these hyperxerophilous broomlands detach themselves easily from main Cytisetea scopario-striati diagnosis, being intermixed in contrasting ecological diagnosis, with major frequency of Calluno vulgaris-Ulicetea minoris elements, under extremely different edaphoclimatic envelopes, different landscapes and serial dynamics.

As result of several field trips following doctoral research in Marianic-Monchiquensean Sector, we describe a new heathland named Lavandulo viridis-Ericetum lusitanici ass nova hoc loco (Genistion micrantho-anglicae, Rivas- Martínez 1979) as a thermomediterranean to lower mesomediterranean, upper dry to humid, schistose association. The analysis of 11 relevés, following Braun-Blanquet methodology shows the floristic identity of this new association as well as the chorological segregation of its area of occurrence. Finally, despite these communities already being relatively well known and although they are poor in species number, such heathlands show floristic singularity and own sinecology, with a large and distinct geographical area of distribution, so we emphasized its integration within Atlantic wet heaths priority habitat (⁄4020 – Annex B-I from Council Directive 92/43/EEC of 21 May 1992).

Time is one of the most important driving forces in Landscape Ecology. Time along with geosystem, biosystem and socialsystem determines landscape heterogeneity which reveals itself in different patterns and functions. Cultural Landscapes are the result of the interactions between man and environment along time.

Évora (the Lusitanian Ebora), the most important town in Alentejo province (Southern Portugal) is involved by a cultural landscape where not only archeological sites and old built structures (walls, roads, bridges houses, etc.) of several epochs are present, but also old parcel networks and specific agro forestry pastoral systems, the montados, exist. In front of a so big quantity of data, the authors have selected four main heritage valuated landscapes: - The holm-oak, cork-oak, or mixed montados landscapes. - The old Augustan roman cadastral networks; - The old Late Empire roman cadastral networks; - The old Medieval ground parcels network; Our first theme is related with holm and cork oak montados, traditional agro forestry pastoral systems classified by law. Beyond the productive function, these cultural landscapes present high biological, scenic and recreational value. In the area several different types with different levels of conservation are present. Other kind of heritage landscapes were also studied: two roman cadastral network involving Ebora (the roman Évora), of different periods and with different orientations, and a medieval parcels network located in the close surroundings of the city. An essay of heritage valuation of those heritage landscapes was also done. Firstly the selection of suitable criteria and related weighting coefficients was established in the sequence of debates with experts. Then the application of a linear combination permitted to estimate heritage value. GIS tools were very useful to the integration of such spatial themes and their analysis. It utilization permitted to determine the zonation of the most valuable heritage landscape areas around Évora. Otherwise the use of GIS database allowed the overlaying of the four heritage landscapes types, as well as the calculation of the networks limits density, permitting to define the most interesting areas to be preserved in land planning projects.

All Organizations recognize that internal methodologies and frameworks are very important to have a thorough knowledge of their potential, simultaneous increase competitiveness and, correspondingly, enhance and optimize the performance of their service. Waste management is a challenge of modern society, and there is awareness that responsibility of waste management should be shared by all community, to cooperate and ensure a sustainable development with the best principles and best management practices. It is a citizenship issue, where citizens contribute adopting preventative behaviours in the production of waste, as well as practices that facilitate waste recycling, reuse and recovery, which contribute to reduce the waste life cycle. This concern and the service improvement involve the minimization of the environmental impacts, the conservation of the natural resources, the reduction of pollutant emissions, as well as the design of the solutions for the collection, transfer and transport, treatment and waste final deposition, and the allocation of human and financial resources. The need for a sustainable management of resources has led to the design and development of management models in waste systems to assess in what extent the various tasks or activities are (or are not) carried out in accordance with the objectives established in advance and the efforts, decisions and operational actions developed by organisations to improve the quality of its work. Thus, given the problems and requirements of the waste sector, it is necessary to outline and plan sustainable strategies for the management system. Therefore, the objective of the present work is the application and study of key concepts related to design and implementation of a management model, the Balanced Scorecard (BSC). This is a management method based on critical success factors, which propose is to translate through a systemic approach, the mission and strategy of Organizations (private or public / nonprofit) in operational objectives, arranged into perspectives interconnected in a cause-effect relation. It connects the strategic objectives to measurable measures (performance indicators) that indicate the success or failure of the adopted strategy, contributing to a review. The BSC is a very useful and simple management tool, which perfectly suits the needs of the waste sector. It works as a measurement and management system, and a basis for the strategy communication to all elements of the system, and through a joint analysis, demonstrates of the importance of all stakeholders to the overall management, encouraging their involvement and motivation.

Dissertação apresentada para obtenção do grau de Doutor, na Faculdade de Engenharia da Universidade do Porto, sob a orientação dos Professores Carlos A. V. Costa e Mohamed Naceur Belgacem