927 resultados para Weak and Strong Solutions


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Two series of new diorganotin(IV) cycloalkylhydroxamate complexes with different ring sizes (cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl), formulated as the mononuclear [R2Sn(HL)(2)] (1:2) (a, R=Bu-n and Ph) and the polymeric [R2SnL](n) (1:1) (b, R=Bu-n) compounds, were prepared and fully characterized. Single crystal X-ray diffraction for [(Bu2Sn)-Bu-n{C5H9C(O)NHO}(2)] (3a) discloses the cis geometry and strong intermolecular NH center dot center dot center dot O interactions. The in vitro cytotoxic activities of the complexes were evaluated against HL-60, Bel-7402, BGC-823 and KB human tumour cell lines, the greater activity concerning [(Bu2Sn)-Bu-n(HL)(2)] [HL=C3H5C(O)NHO (1a), C6H11C(O)NHO (4a)] towards BGC-823. The complexes undergo, by cyclic voltammetry and controlled-potential electrolysis, one irreversible overall two-electron cathodic process at a reduction potential that does not appear to correlate with the antitumour activity. The electrochemical behaviour of [R2Sn(C5H9C(O)NHO)(2)] [R=Bu-n (3a), Ph (7a)] was also investigated using density functional theory (DFT) methods, showing that the ultimate complex structure and the mechanism of its formation are R dependent: for the aromatic (R = Ph) complex, the initial reduction step is centred on the phenyl ligands and at the metal, being followed by a second reduction with Sn-O and Sn-C ruptures, whereas for the alkyl (R=Bu-n) complex the first reduction step is centred on one of the hydroxamate ligands and is followed by a second reduction with Sn-O bond cleavages and preservation of the alkyl ligands. In both cases, the final complexes are highly coordinative unsaturated Sn-II species with the cis geometry, features that can be of biological significance.

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The wide spread use and strong reliance on both fertilizers and pesticides made of agrigenic pollution one of the major contemporary threats to environment and human health. Impacts on the environment vary from local effects, such as eutrophycation1, 2, loss of biodiversity and diminished ecosystem health3, to global effects, such as the aggravation of global warming2, 4 and ozone layer depletion5. The novelty of nanoremediation and its early successes, reported for various contexts, present the prospect for the development of relevant applications for agrigenic contaminants.

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All over the world, the liberalization of electricity markets, which follows different paradigms, has created new challenges for those involved in this sector. In order to respond to these challenges, electric power systems suffered a significant restructuring in its mode of operation and planning. This restructuring resulted in a considerable increase of the electric sector competitiveness. Particularly, the Ancillary Services (AS) market has been target of constant renovations in its operation mode as it is a targeted market for the trading of services, which have as main objective to ensure the operation of electric power systems with appropriate levels of stability, safety, quality, equity and competitiveness. In this way, with the increasing penetration of distributed energy resources including distributed generation, demand response, storage units and electric vehicles, it is essential to develop new smarter and hierarchical methods of operation of electric power systems. As these resources are mostly connected to the distribution network, it is important to consider the introduction of this kind of resources in AS delivery in order to achieve greater reliability and cost efficiency of electrical power systems operation. The main contribution of this work is the design and development of mechanisms and methodologies of AS market and for energy and AS joint market, considering different management entities of transmission and distribution networks. Several models developed in this work consider the most common AS in the liberalized market environment: Regulation Down; Regulation Up; Spinning Reserve and Non-Spinning Reserve. The presented models consider different rules and ways of operation, such as the division of market by network areas, which allows the congestion management of interconnections between areas; or the ancillary service cascading process, which allows the replacement of AS of superior quality by lower quality of AS, ensuring a better economic performance of the market. A major contribution of this work is the development an innovative methodology of market clearing process to be used in the energy and AS joint market, able to ensure viable and feasible solutions in markets, where there are technical constraints in the transmission network involving its division into areas or regions. The proposed method is based on the determination of Bialek topological factors and considers the contribution of the dispatch for all services of increase of generation (energy, Regulation Up, Spinning and Non-Spinning reserves) in network congestion. The use of Bialek factors in each iteration of the proposed methodology allows limiting the bids in the market while ensuring that the solution is feasible in any context of system operation. Another important contribution of this work is the model of the contribution of distributed energy resources in the ancillary services. In this way, a Virtual Power Player (VPP) is considered in order to aggregate, manage and interact with distributed energy resources. The VPP manages all the agents aggregated, being able to supply AS to the system operator, with the main purpose of participation in electricity market. In order to ensure their participation in the AS, the VPP should have a set of contracts with the agents that include a set of diversified and adapted rules to each kind of distributed resource. All methodologies developed and implemented in this work have been integrated into the MASCEM simulator, which is a simulator based on a multi-agent system that allows to study complex operation of electricity markets. In this way, the developed methodologies allow the simulator to cover more operation contexts of the present and future of the electricity market. In this way, this dissertation offers a huge contribution to the AS market simulation, based on models and mechanisms currently used in several real markets, as well as the introduction of innovative methodologies of market clearing process on the energy and AS joint market. This dissertation presents five case studies; each one consists of multiple scenarios. The first case study illustrates the application of AS market simulation considering several bids of market players. The energy and ancillary services joint market simulation is exposed in the second case study. In the third case study it is developed a comparison between the simulation of the joint market methodology, in which the player bids to the ancillary services is considered by network areas and a reference methodology. The fourth case study presents the simulation of joint market methodology based on Bialek topological distribution factors applied to transmission network with 7 buses managed by a TSO. The last case study presents a joint market model simulation which considers the aggregation of small players to a VPP, as well as complex contracts related to these entities. The case study comprises a distribution network with 33 buses managed by VPP, which comprises several kinds of distributed resources, such as photovoltaic, CHP, fuel cells, wind turbines, biomass, small hydro, municipal solid waste, demand response, and storage units.

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Dissertação para obtenção do Grau de Mestre em Biotecnologia

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This thesis focused on the study and treatment of a 19th century female portrait in oil from ECOMUSEU Municipal do Seixal, Portugal. The portrait, which depicts Isabel Maria Lourenço Affonso was in poor condition and a large strip of paint and canvas was missing (approximately 9cm by 66cm, almost 11% of the total surface area). The portrait is a companion piece to a male portrait (the relationship was established as part of this study), therefore a technical study of both paintings was considered essential to support the choices made during the treatment. The project involved three main areas: - The study of the history, condition, materials and techniques of both paintings. This allowed their comparison and understanding of their relationship; - The treatment of Isabel Maria Lourenço Affonso. The choices made and problems encountered are described. - The production of a replacement for the missing strip of paint and canvas. The practical solution developed to overcome such an unusual challenge is described along with the creative and flexible thinking required. Because not all traditional infill materials cope well on a mechanical level with thin layers over a very large surface (many are too brittle), strict criteria had to be employed to choose the appropriate material. The primary goal was to find a fill which would remain flexible and be capable of accepting surface texture, such that there would be a good visual match with the painting. Analysis and testing was carried out to evaluate the physical properties of the fill material chosen, BEVA® Gesso-P. The successful creation of the replacement strip has resulted in two publications and one presentation: Publication pending in The Picture Restorer, Leslie Carlyle, Raquel Marques, Isabel Pombo Cardoso and Sara Babo, “Creating a Textured Replacement Strip for the Missing Lower Portion of an Oil Portrait: Problem Solving and Practical Solutions”. Abstract accepted for presentation and publication, International Meeting on Retouching of Cultural Heritage (2RECH), Raquel Marques, Leslie Carlyle and Isabel Pombo Cardoso, “Textured Replacement Strip for a Missing Portion of a Portrait: Problem Solving and Practical Solutions”.

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RESUMO: Introdução: Vários estudos têm encontrado evidência para a relação entre as crenças e atitudes dos profissionais de saúde, a sua abordagem de tratamento, referida como orientada segundo o modelo biomédico ou modelo biopsicossocial (Bishop, 2008; Mutsaers, 2012), e os resultados obtidos. É sugerido que, no tratamento da dor lombar crónica, os profissionais que orientam o seu raciocínio e prática segundo o modelo biomédico, tendem a obter piores resultados quando comparados com os obtidos pelos profissionais que orientam o seu raciocínio e prática segundo uma abordagem biopsicossocial. Esta área de estudo tem salientado a importância de desenhar instrumentos capazes de identificar a orientação preferencial dos profissionais de saúde no tratamento da dor crónica de natureza músculo-esquelética, entre os quais se encontra a “Pain Attitudes and Beliefs Scale for Physiotherapists” (PABS-PT). Objetivo: Adaptar culturalmente a PABS-PT para a população de fisioterapeutas portugueses que intervêm em utentes com dor (lombar) crónica, e contribuir para a sua validação Metodologia: A versão original (língua inglesa) do PABS-PT foi adaptada para a língua e cultura portuguesas, através das etapas definidas nas normas orientadoras estabelecidas para este processo (Beaton et al., 2002; MAPI Institute, 2001). A avaliação das propriedades psicométricas da versão portuguesa foi realizada com recurso a uma amostra de 202 fisioterapeutas e estudantes finalistas do curso de licenciatura em Fisioterapia. Inicialmente foi realizada a análise fatorial exploratória da escala através do método das componentes principais. Posteriormente avaliou-se a consistência interna das componentes obtidas com recurso ao alpha de Cronbach (α). Para analisar a validade de constructo foram correlacionadas as componentes obtidas com a versão portuguesa da “Health Care Providers’ Pain and Impairment Relationship Scale” (HC-PAIRS), recorrendo ao cálculo do coeficiente de Spearman. Resultados: O processo de adaptação cultural não revelou dificuldades importantes sendo considerado que a versão portuguesa da PABS-PT é de fácil compreensão e preenchimento, e os seus itens adequados para avaliar as crenças e atitudes dos fisioterapeutas portugueses relativas à intervenção na dor crónica músculo-esquelética. Os resultados revelaram uma estrutura fatorial de duas componentes, identificadas com as componentes da escala original que explicam 30,96% da variância total. A consistência interna encontrada é boa, para a componente biomédica (α de Cronbach = 0,826), mas muito fraca para a componente biopsicossocial (α de Cronbach= 0,589). Relativamente à validade convergente e discriminativa, foi encontrada uma associação estatisticamente significativa e positiva, entre as componentes 1 (biomédica) da versão nportuguesa da PABS e a HC-PAIRS (Rs = 0,481, p≤ 0,005), e negativa, fraca e significativa entre a pontuação total da componente 2 (biopsicossocial) e a HC-PAIRS (Rs = -0,038, p=0,612). Conclusão: A versão portuguesa do PABS-PT é de fácil compreensão e aparenta ser um instrumento válido para a medição da orientação preferencial dos fisioterapeutas, relativamente às suas atitudes e crenças na avaliação e tratamento de utentes com dor crónica de natureza músculo-esquelética. No entanto, a componente biopsicossocial requer uma análise mais aprofundada para que possa, com rigor, ser utilizada na definição de uma orientação preferencialmente biopsicossocial.--------------ABSTRACT: Introduction: Previous studies have found a relation between the beliefs and attitudes of health professionals, their treatment approach, which can follows a biomedical or a biopsychosocial orientation (Bishop, 2008; Mutsaers, 2012), and the outcomes obtained. Therefore, is suggested that the professionals who tend to approach chronic low back pain patients according to the biomedical model have worse outcomes than professionals who use a biopsychosocial approach in there clinical reasoning. This research field has highlighted the importance of developing measures capable of identifying the preferred orientation of health professionals in the treatment of chronic pain of musculoskeletal nature, including the “Pain Attitudes and Beliefs Scale for Physiotherapists” (PABS-PT). Objective: To cross culturally adapt and validate the PABS-PT for the Portuguese population of physiotherapists. Methodology: The original version (English version) of the PABS-PT was adapted to the Portuguese language and culture, through the guidelines established for these processes (Beaton et al., 2002; MAPI Institute, 2001). The psychometric evaluation of the Portuguese version was carried out on a sample of 202 p physiotherapist and final year students of the physiotherapy course. Initially, an exploratory factorial analysis was performed through the method of the main components. Then, the internal consistence of the main components was evaluated using the Cronbach’s alpha (α). The convergent construct validity was analysed through the correlation between the obtained components of PABS-PT and the Health Care Provider’s Pain and Impairment Relationship Scale (HC-PAIRS), using the Spearmen correlation coefficient. Results: No major difficulties were found during the cultural adaptation process of PABS-PT to Portugal, which means that the Portuguese version is easy to understand and fulfill, and items are appropriated to evaluate the beliefs and attitudes of the Portuguese physiotherapists who treat chronic pain of musculoskeletal origins. The results revealed a factorial structure of two components, as the original scale, explaining 30,96% of the total variance. Internal consistence results were good, for the biomedical component (Cronbach’s α = 0,826), but very weak for the biopsychosocial componente (Cronbach’s α = 0,589). Relatively to convergent and discriminative validity, a statistically significant association was found, between the components 1 (biomedical) of the Portuguese version of PABS-PT and the HC-PAIRS (Rs= 0,481, p≤ 0,005) and negative, weak and significant between the total score of component 2 (biopsychosocial) and the HC-PAIRS (Rs = -0,038, p=0,612). Conclusion: The Portuguese Version of PABS-PT is easy to understand and seems to be a valid instrument to measure the attitudes and beliefs of physiotherapists in the management of patients with chronic low back pain. However, the biopsychosocial component requires a further deep analysis to examine a preferable biopsychosocial orientation.

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Ionic Liquids (ILs) consist in organic salts that are liquid at/or near room temperature. Since ILs are entirely composed of ions, the formation of ion pairs is expected to be one essential feature for describing solvation in ILs. In recent years, protein - ionic liquid (P-IL) interactions have been the subject of intensive studies mainly because of their capability to promote folding/unfolding of proteins. However, the ion pairs and their lifetimes in ILs in P-IL thematic is dismissed, since the action of ILs is therefore the result of a subtle equilibrium between anion-cation interaction, ion-solvent and ion-protein interaction. The work developed in this thesis innovates in this thematic, once the design of ILs for protein stabilisation was bio-inspired in the high concentration of organic charged metabolites found in cell milieu. Although this perception is overlooked, those combined concentrations have been estimated to be ~300 mM among the macromolecules at concentrations exceeding 300 g/L (macromolecular crowding) and transient ion-pair can naturally occur with a potential specific biological role. Hence the main objective of this work is to develop new bio-ILs with a detectable ion-pair and understand its effects on protein structure and stability, under crowding environment, using advanced NMR techniques and calorimetric techniques. The choline-glutamate ([Ch][Glu]) IL was synthesized and characterized. The ion-pair was detected in water solutions using mainly the selective NOE NMR technique. Through the same technique, it was possible to detect a similar ion-pair promotion under synthetic and natural crowding environments. Using NMR spectroscopy (protein diffusion, HSQC experiments, and hydrogen-deuterium exchange) and differential scanning calorimetry (DSC), the model protein GB1 (production and purification in isotopic enrichment media) it was studied in the presence of [Ch][Glu] under macromolecular crowding conditions (PEG, BSA, lysozyme). Under dilute condition, it is possible to assert that the [Ch][Glu] induces a preferential hydration by weak and non-specific interactions, which leads to a significant stabilisation. On the other hand, under crowding environment, the [Ch][Glu] ion pair is promoted, destabilising the protein by favourable weak hydrophobic interactions , which disrupt the hydration layer of the protein. However, this capability can mitigates the effect of protein crowders. Overall, this work explored the ion-pair existence and its consequences on proteins in conditions similar to cell milieu. In this way, the charged metabolites found in cell can be understood as key for protein stabilisation.

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RESUMO: Santa Lúcia pequena ilha de país em desenvolvimento com recursos limitados e é confrontada com uma série de desafios socioeconômicos que exigem soluções criativas e inovadoras. É comprovado que a combinação de recursos entre setores para estabelecer os determinantes social, econômico e ambiental da saúde são uma estratégia útil para melhorar a saúde da população, principalmente a sua saúde mental. Este estudo, o primeiro do seu tipo em Santa Lúcia, procurou examinar até que ponto a disponibilidade de uma política nacional de saúde mental levou a ação intersetorial para o fornecimento de serviços e promoção da saúde mental. Além disso, o estudo examinou o nível de colaboração intersetorial que existe entre as agências que prestam cuidados diretos e serviços de suporte para pessoas com doenças mentais e problemas sérios de saúde mental. O estudo também teve como objetivo identificar os fatores que promovem ou dificultam a colaboração intersectorial e gerar recomendações que possam ser aplicadas para países muito pequenos e com perfis socioeconômicos semelhantes. Os dados gerados a partir de três (3) fontes foram sintetizados para formar uma visão ampla das questões. Uma avaliação da política de saúde mental de 2007, uma avaliação que identifica até que ponto a ação intersetorial atualmente deixa a prestação de serviços de saúde mental e a administração de entrevistas semiestruturadas nas mãos de gestores do programa de diferentes agências em todos os setores. O estudo concluiu que, apesar da disponibilidade de uma política de saúde mental, que articula clara e explicitamente a colaboração intersetorial como área prioritária para ação, quase não existe no sistema de fornecimento atual do serviço. Os provedores de serviços em todos os setores reconhecem que há os benefícios da colaboração intersectorial e com entraves significativos em relação à colaboração intersetorial, que por sua vez, impede uma abordagem nacional para o planejamento e o fornecimento do serviço. A colaboração intersetorial não será possível se os próprios setores dependerem da abordagem direta do setor da saúde ou se a atmosfera geral for ofuscada pela estigmatização das doenças mentais.------------------------------------------------------------------------ABSTRACT: Saint Lucia a small island developing country with limited resources, is faced with a number of socio-economic challenges which require creative and innovative solutions to address. Combining resources across sectors to address the social, economic and environmental determinants of health has proven to be a useful strategy for improving population health in particular mental health. This study, the first of its kind for Saint Lucia sought to examine the extent to which the availability of a national mental health policy led to intersectoral action for mental health promotion and service delivery. In addition the study examined the level of intersectoral collaboration which actually exist between agencies which provide direct care and support services to people with mental illnesses and significant mental health problems. The study also aimed to identify the factors which promote or hinder intersectoral collaboration and generate recommendations which can be applied to extremely small countries with similar socio-economic profiles. Data generated from three (3) sources was synthesized to form a broad picture of the issues. An evaluation of the mental health policy of 2007, an assessment of the extent to which intersectoral action currently exist in mental health service delivery and the administration of semi-structured interviews with program managers from different agencies across sectors to identify implementation issues. The study concluded that despite the availability of a mental health policy which clearly and explicitly articulates intersectoral collaboration as a priority area for action, very little exists in the current service delivery system. Services providers across sectors acknowledge the benefits of intersectoral collaboration and that there are significant barriers to intersectoral collaboration, which in turn hinders a national approach to service planning and delivery. Intersectoral collaboration is not possible if sectors themselves are dependent on a top-down health sector driven and dominated approach, or if the general atmosphere is clouded by stigmatization of mental health illnesses.

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One important component with particular relevance in battery performance is the cathode, being one of the main responsible elements for cell capacity and cycle life. Carbon coated lithium iron phosphate, C-LiFePO4, active material is one of the most promising cathode materials for the next generation of large scale lithium ion battery applications and strong research efforts are being devoted to it, due to its excellent characteristics, including high capacity, ~170 mAh/g, and safety. This review summarizes the main developments on C-LiFePO4 based cathode film preparation and performance. The effect of the binder, conductive additive, relationship between active material-binder-conductive additive and drying step, in the electrode film fabrication and performance is presented and discussed. Finally, after the presentation of the cell types fabricated with C-LiFePO4 active material and their performance, some conclusions and guidelines for further investigations are outlined.

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The increase in life expectancy with a decrease in birth rates is contributing to the ageing of the European population. This phenomenon, coupled with greater awareness of the quality of life, the need to have cost-efficient assistive care, the intention of people to live independently in their homes, and the technological developments in recent decades, have contributed to the emergence of the concept of ambient assisted living (AAL). AAL solutions aim to provide healthy and safe ageing to users through promoting independence in performing daily activities and interacting with technology, taking into consideration the deterioration of the users’ capabilities and the reduced costs of the solutions. In this chapter, AAL developments of monitoring activities of daily living (ADLs) and participation in a virtual community with the selected stakeholders are introduced, their roadmap with the expected technological developments are described, and the expected impact of these solutions on the end users of the developed solutions are discussed. This enables a real user guidance structure that represents the different needs and limitations of each user, presenting a highly structured project based on personas and possible solutions for them. The AAL4ALL Ambient Assisted Living for All (ALL4ALL) project is considered here as a case study to analyze and illustrate the ALL concepts discussed in this chapter.

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Dissertação de mestrado em Design de Comunicação de Moda

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Tese de Doutoramento em Engenharia de Eletrónica e de Computadores

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Relatório de atividade profissional de mestrado em Direito dos Contratos e da Empresa

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Over the last two decades the results of randomized clinical studies, which are powerful aids for correctly assessing therapeutical strategies, have consolidated cardiological practice. In addition, scientifically interesting hypotheses have been generated through the results of epidemiological studies. Properly conducted randomized studies without systematic errors and with statistical power adequate for demonstrating moderate and reasonable benefits in relevant clinical outcomes have provided reliable and strong results altering clinical practice, thus providing adequate treatment for patients with cardiovascular disease (CVD). The dissemination and use of evidence-based medicine in treating coronary artery disease (CAD), heart failure (HF), and in prevention will prevent hundreds of thousands of deaths annually in developed and developing countries. CVD is responsible for approximately 12 million deaths annually throughout the world, and approximately 60% of these deaths occur in developing countries. During recent years, an increase in mortality and morbidity rates due to CVD has occurred in developing countries. This increase is an indication that an epidemiological (demographic, economical, and health-related) transition is taking place in developing countries and this transition implies a global epidemic of CVD, which will require wide-ranging and globally effective strategies for prevention. The identification of conventional and emerging risk factors for CVD, as well as their management in high-risk individuals, has contributed to the decrease in the mortality rate due to CVD. Through a national collaboration, several multi-center and multinational randomized and epidemiological studies have been carried out throughout Brazil, thus contributing not only to a generalized scientific growth in different Brazilian hospitals but also to the consolidation of an increasingly evidence-based clinical practice.

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Morphometric variability among shrimp populations of the genus Palaemonetes Heller, 1869 from seven lakes (Huanayo and Urcococha, in Peru; Amanã, Mamirauá, Camaleão, Cristalino e Iruçanga, in Brasil) in the Amazon Basin, presumably belonging to Palaemonetes carteri Gordon, 1935 and Palaemonetes ivonicus Holthuis, 1950, were studied. The morphometric studies were carried out from the ratios obtained from the morphometric characters. Multivariated analysis (Principal Components Analysis-PCA, Discriminant Function Analysis and Cluster Analysis) were applied over the ratios. Intra- and interpopulation variations of the rostrum teeth, and the number of spines in the male appendix, were analyzed through descriptive statistics and bivariate analysis (Spearman Rank Correlation test). Results indicated a wide plasticity and overlapping in the studied ratios between populations. The Principal Components Analysis was not able to separate different populations, revealing a large intrapopulation plasticity and strong interpopulation similarity in the studied ratios. Although the Discriminant Functions Analysis was not able to fully discriminate populations, they could be allocated in three subgroups: 1) Cristalino and Iruçanga; 2) Huanayo, Urcococha and Camaleão and 3) Mamirauá and Amanã. The first two groups were morphometrically separated from each other, whereas the third one presented a strong overlap with the former two. The Cluster Analysis confirmed the first two subgroups separation, and indicated that the first and third groups were closely related. Rostrum teeth and number of spines in the appendix masculina showed a large intrapopulation variation and a strong overlapping among the studied populations, regardless of the species.