Stock assessment and management of multi-species fisheries:the case study of flatfish fisheries in the portuguese coast

Tese de doutoramento, Biologia (Biologia Marinha), 2009, Universidade de Lisboa, Faculdade de CiênciasResumo alargado em português disponível no documentoFundação para a Ciência e Tecnologia (FCT), SFRH/BD/19319/2004 and the European Union FEDER-Fisheries Programme (MARE

Searching for clusters in tourism. A quantitative methodological proposal

The tourism industry is one of Europe’s leading employers, and for many regions highly dependent on tourists’ spending, innovation is the difference between growth and stagnation. Thus, at a regional level, tourism may function as a driving force of socioeconomic development and thus contribute to the demise of regional disparities. Such lever effect is usually associated to a geographical concentration abusively denominated of clusters. Most of the studies within the tourism industry identify clusters resorting to simplistic analyses of geographic location measures or experts’ opinions. These latter tend to neglect the essence of the cluster concept, namely the inter-linkages among regional actors. In the present paper, we propose a methodology to rigorously identify tourism clusters, stressing the importance of networks and cooperation between agents.Clusters; Tourism; Methodology

The ‘de-territorialisation of closeness’ - a typology of international successful R&D projects involving cultural and geographic proximity

Although there is a considerable amount of empirical evidence on inter-firm collaborations within technology-based industries, there are only a few works concerned with R&D cooperation by low-tech firms, especially SMEs. Providing further and new evidence based on a recently built database of CRAFT projects, this study analyzes the relationship between technology and proximity in international R&D networks using Homogeneity Analysis by Means of Alternating Least Squares (HOMALS) and statistical cluster techniques. The resulting typology of international cooperative R&D projects highlights that successful international cooperative R&D projects are both culturally/geographically closer and distant. Moreover, and quite interestingly, geographically distant projects are technologically more advanced whereas those located near each other are essentially low tech. Such evidence is likely to reflect the tacit-codified knowledge debate boosted recently by the ICT “revolution” emphasized by the prophets of the “Death of Distance” and the “End of Geography”.Research and Development (R&D); proximity; SMEs

Classification of Energy Momentum Tensors in n≥5n \geq 5 Dimensional Space-times: a Review

Recent developments in string theory suggest that there might exist extra spatial dimensions, which are not small nor compact. The framework of a great number of brane cosmological models is that in which the matter fields are confined on a brane-world embedded in five dimensions (the bulk). Motivated by this we review the main results on the algebraic classification of second order symmetric tensors in 5-dimensional space-times. All possible Segre types for a symmetric two-tensor are found, and a set of canonical forms for each Segre type is obtained. A limiting diagram for the Segre types of these symmetric tensors in 5-D is built. Two theorems which collect together some basic results on the algebraic structure of second order symmetric tensors in 5-D are presented. We also show how one can obtain, by induction, the classification and the canonical forms of a symmetric two-tensor on n-dimensional (n > 5) spaces from its classification in 5-D spaces, present the Segre types in n-D and the corresponding canonical forms. This classification of symmetric two-tensors in any n-D spaces and their canonical forms are important in the context of n-dimensional brane-worlds context and also in the framework of 11-D supergravity and 10-D superstrings.Comment: LaTex2e, 18 pages. To appear in Braz.J.Phys (2004

A new look into the evolution of clusters literature. A bibliometric exercise

In the contemporary globalising knowledge-based economies, local clusters have become crucial elements of regional development, assuming a significant role in both academic and political fields. Although there is an intuitive awareness about the raising importance of the theoretical debate on clusters, there is a substantial lack of empirical support of its precise magnitude and evolution. Moreover, the majority of literature surveys on clusters are exclusively qualitative-based. Aiming at filling this gap, the main purpose of this paper is to provide a quantitative survey of the cluster literature, using bibliometric techniques based on articles. Based on a throughout analysis of all abstracts of articles on clusters published in journals indexed on the Econlit and EBSCO databases, covering the period 1962-2007, our research show that besides their importance in academic fields, the role of clusters has also been widely acknowledged in political spheres. In parallel with the increasing interest in the ‘local’, there has been, as well, an emergent body of literature on global networks and clusters. Moreover, on the basis of the recent boom on clusters literature stands the emergent themes of ‘local networks and social approaches’ and ‘knowledge-based theories’. Literature associated to ‘regional and national innovation systems’ and to ‘institutional approaches’ (local enrooted cultures, governance and customs) has been object of a particular dynamism since the 1990s. Despite the evidence of a clear positive correlation between journals ‘quality’ and formal related research, the evolution of the literature on clusters continues to be mostly appreciative led.Clusters, Industrial Clusters, Industrial Location; Bibliometrics

The Informativeness of Quarterly Financial Reporting: The Portuguese Case

With the Directive 2004/109/EC, of December 15, 2004 – Transparency Directive –, the European Union decided not to require listed companies to disclose financial information in the first and third quarters of each year. Each EU country now has to decide whether to oblige its companies to disclose this information. Using a sample of 1751 firm-earnings announcements between 1994 and 2004, this paper ascertains the informativeness of quarterly financial reporting in Portugal, one of the seven European countries where the disclosure of such information is currently compulsory in all quarters. Evidence suggests that the information of the first and third quarters, both in terms of price volatility and trading volume, is significant and not inferior to that of the remaining earnings announcements.Capital markets-based research; interim accounting disclosure; market reaction; market regulation

Foliations, solvability and global injectivity

Let F: R^n -> R^n be a C^\infty map such that DF(x) is invertible for all x in R^n. We know that F is a local diffeomorphism but, in general, it is not globally injective. We discuss the relations between some additional hypothesis that guarantee the global injectivity of F. Further, based on one of these hypotheses, we establish a necessary condition for the existence of F: R^n -> R^n such that det DF = h, where h: R^n -> [0,\infty) is a given C^\infty function

Uma proposta para a Paz passa pelo alargamento da UE : terá a Europa coragem para levar a União até á África Ocidental?

Campus Social : Revista Lusófona de Ciências SociaisIn the same manner that the struggle of classes, born in the industrial revolution in the XVII and XVIII century, was neither a confrontation nor an arrangement between the working class and the bourgeois. Today, in globalization, the cultural conflicts are not solved through confrontation or from the dialogue between civilizations. The broadening of the European Union is much more urgent than its deepening. It many imply an European Union at various velocities, but it may be the answer to terrorism. There must be courage to take the European borders beyond Turkey and even beyond the Middle East and Magreb. It is time to think of broadening it to include Western Africa, where Al Qaeda is moving in

Ionic liquids in the fractionation of terpenes and other relevant separation problems

Mestrado de dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáTerpenes include a great variety of compounds with different functions, some acting as flavoring or aroma agents, or organic solvents, while others can be used as raw material for the synthesis of other compounds of commercial interest in different industrial areas. With an increase in environmental concern, some terpenes can represent greener options for industrial processes, increasing the interest of the scientific community on its properties and behavior. In order to purify those compounds and their mixtures, and therefore increase their value, various methods are applied. Among those methods, vacuum distillation has been widely applied. Furthermore, studies associating with ionic liquids (ILs) as separation agents in deterpenation processes hold economical and environment appeal. In the present work, infinite dilution activity coefficient data of several organic solutes (alkanes, cycloalkanes, ketones, ethers, cycloethers, aromatic hydrocarbons, esters, acetonitrile, pyridine, thiophene, alcohols, terpenes and terpenoids) and water in selected ionic liquids ([P6,6,6,14][(C8H17)2PO2] or [P6,6,6,14][Cl]) were obtained by gas-liquid chromatography (GLC), aiming to estimate selectivities and capacities values related to different separation problems including those involving terpenes mixtures. Both ILs tested showed poor entrainment potential regarding the α-pinene/β-pinene separation, while [P6,6,6,14][(C8H17)2PO2] showed potential as an entrainer in the limonene/linalool separation. The partial excess energies of alcoholic solutes showed the most distinct behavior from all solutes in both ILs, indicating to be mostly governed by enthalpic interactions.Terpenos abrangem uma grande variedade de compostos um funções distintas, alguns agindo como agentes de sabor e aroma, ou solventes orgânicos, enquanto outros podem ser usados como matéria-prima para sínteses de compostos de interesse comercial no âmbito industrial. Com o aumento da consciência ambiental, terpenos representam opções mais verdes para processos industriais, tendo aumentando enormemente o interesse da comunidade cientifica nas suas propriedades e comportamentos. Para purificar esses compostos e suas misturas, adicionando-lhe valor, vários métodos são aplicados. Dentre esses métodos, destilação a vácuo tem sido amplamente aplicado. Além disso, estudos associando líquidos iônicos (LIs) como agentes de separação in desterpanações carrega apelo econômico e ambiental. No presente trabalho, coeficientes de atividade a diluição infinita de vários solventes orgânicos (alcanos, ciclo alcanos, cetonas, éteres, ciclo éteres, hidrocarbonetos aromáticos, ésteres, acetonitrilo, piridina, terpenos e terpenóides) e agua em líquidos iônicos ([P6,6,6,14][(C8H17)2PO2] ou [P6,6,6,14][Cl]) são obtidos por meio de cromatografia gás-líquido, almejando estimar valores de seletividades e capacidades relacionados a diferentes separações comuns, bem como aquelas contendo misturas de terpenos. Ambos LIs testados mostraram pouco potencial como facilitadores da separação α-pineno/β-pineno, enquanto [P6,6,6,14][(C8H17)2PO2] mostrou potencial como facilitador da separação limoneno/linalol. As energias parciais em excesso dos solutos alcoólicos mostraram o comportamento mais distintos entre todos os solutos, com tipo de interação de dominância entálpica

MUC1 polymorphism in relation to susceptibility to Helicobacter pylori gastritis.

The gene MUC1 encodes a transmembrane mucin glycoprotein that is expressed on the apical surface of most epithelia and is aberrantly expressed in cancer. MUC1 contains an extended domain of tandemly repeated (TR) amino-acid sequence, which acts as the backbone for a large amount of O-linked glycosylation, and which varies in length and sequence in different alleles. Previous studies on MUC1 tandem repeat variation in patients with gastritis (Vinall et al, 2002) and gastric cancer (Carvalho et al, 1997) showed an overrepresentation of short TR alleles in the patient groups when compared with normal controls. The major aim of this thesis is to pursue this observation further. MUC1 allele and three locus haplotype frequencies were compared in 3 populations of different ancestry, from UK, Nigeria and Portugal, which show dramatic differences in gastric disease incidence in patients with gastric disease, patients with other gastrointestinal disease as well as associated controls. There were differences between the Nigerians and unselected European control groups, but there was no significant difference between the groups collected in London and Porto. Analysis of the gastric disease groups showed an over-representation of a particular MUC1 haplotype. A search was made, by sequencing and using a bioinformatics approach, for additional polymorphic markers within and surrounding the MUC1 gene, that might act as convenient markers for future disease association studies. Patterns of Linkage Disequilibrium were established across a 600Kb genomic region containing MUC1 using information in the HapMap resource and this information was used to assist in the selection of the single nucleotide polymorphisms (SNPs) within a 70Kb region to test on disease groups. During the course of this thesis work, a second UK cohort of patients and controls was collected and characterised and a replication study attempted. DNA samples from a total of 154 Northern Europeans classified as H. pylori gastritis (n=33), former H. pylori gastritis (n=44), No H. pylori gastritis (n=18) and normal (n=59). Examination of the MUC1 polymorphisms failed to show over-representation, in the H. pylori gastritis group, of the same haplotype found in the first gastritis cohort. The extended 70Kb haplotypes showed the expected association in the first cohort but no significant differences in the second cohort. However, in the population overall, it was noteworthy that there is a very high frequency haplogroup containing long tandem repeat arrays and this was somewhat lower in frequency in both H. pylori gastritis groups