Development and standardization of a protocol for sperm cryopreservation of two important commercial oyster species

Dissertação de mestrado, Aquacultura e Pescas, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015Aquaculture activities have a huge contribution for the world food production and their development is extremely necessary to answer to the lack of resources, especially to the demand for seafood. Bivalve production, especially Crassostrea angulata (Portuguese oyster) has been practiced from long ago, and although its production suffered several constraints, in recent years it has been increasing the interests in recovering production and in preserving nature populations. In this sense, new research needs to guarantee an efficient and economically viable production, contributing to a relatively new environmental concern: wild population restoration. Nowadays, pure wild populations of Crassostrea angulata are rare to find due to multiple factors that affected this oyster industry. Cryopreservation technology could promote alternative techniques to contribute for the resource management efficiency of the Portuguese oyster and associated economic activity. In this sense, standardization of procedures is important for Crassostrea genus. At the present there are no cryopreservation reports on Crassostrea angulata sperm, and therefore, one of the objectives of this work is to design a cryopreservation protocol for this species, testing the more adequate cryoprotectant solution, its ideal concentration, different freezing rates and types of containers. In parallel, this stablished protocol was applied in Crassostrea gigas and compared to other previously published for this species. Analysis of motility, viability, agglutination and fertilizations were used as guides for the establishment of the protocol in C. angulata. Moreover, ATP content, DNA fragmentation and lipid peroxidation were done in order to standardize the same protocol for both species. Movement analysis were assessed by CASA system, viability through common staining techniques and flow cytometer, agglutination was quantified according to the scale developed by Dong et al., (2007), ATP content determined by bioluminescence, Comet assay was performed to quantify the DNA fragmentation and lipid peroxidation determined spectrophotometrically by measuring the absorbance of the malondialdehyde (MDA). Significant differences were observed (p<0.05) for lipid peroxidation and fertilization trials whereas ATP content and fragmentation of DNA of the cryopreserved samples did not differ significantly from the control. In C. gigas, the same analysis were performed and did not reveal post-thaw quality differences in the samples cryopreserved with 10% DMSO. The established protocol revealed to be effective and with a low degree of cellular damage on C. angulata sperm and, at the same time, viable to apply in other species, such as Crassostrea gigas

O potencial biotecnológico dos bacteriófagos na deteção e controlo de bactérias patogénicas

Os bacteriófagos (fagos) apresentam um imenso potencial biotecnológico com aplicação na saúde devido às suas características intrínsecas de reconhecimento e morte do hospedeiro que infetam (bactérias). A exploração destas características no desenvolvimento de métodos de deteção e de controlo de bactérias patogénicas é relativamente recente, embora a utilização de fagos como ferramentas de biologia molecular seja bastante antiga e a terapia fágica uma prática secular, actualmente limitada a alguns países

Phages/biofilm interaction: strategies to improve phage efficacy against infectious biofilms

The complex heterogeneous structure of biofilms confers to bacteria an important survival strategy. Biofilms are frequently involved in many chronic infections in consequence of their low susceptibility to antibiotics as well as resistance to host defences. The increasing need of novel and effective treatments to target these complex structures has led to a growing interest on bacteriophages (phages) as a strategy for biofilm control and prevention. Theoretically, the close proximity of cells within the biofilm structure could enhance phage-host interaction and facilitate phage infection. Conversely, the biofilm structure and composition as well as the physiological state of the biofilm cells may be an obstacle to phage infection. Nonetheless, phages have developed mechanisms to overcome biofilm barriers in a natural evolutionary prey-predator model. A thorough characterisation of biofilm/phage interaction and the identification of the weak aspects of biofilms and the strong features of phages are thus important to develop efficient phage-based biofilm control strategies. Phages can be used alone, as a cocktail to broaden the spectra of activity, or in combination with other antimicrobials to improve their efficacy. In this presentation studies involving the use of phages for the treatment or prevention of bacterial biofilms will be summarized, highlighting the biofilm features that can be tackled with phages or combined therapy approaches.info:eu-repo/semantics/publishedVersio

Marketing plan NOS: introducing pay per view

NOS, NOS Comunicações S.A., is a private telecommunications company of the portuguese market which is proud of being the “best communications and entertainment company in the market”. The company was born from a fusion between two of the biggest communications corporations in the country: on the fixed service (TV, fixed phone, fixed internet, etc.) from ZON; and on the mobile service (mobile phone, internet, etc.) from Optimus. It is a leader in all the sectors it operates. Besides telecommunications, NOS is the main enterprise in the cinema exhibition market in Portugal ( NOS Cinemas – with 62% of market share) and the main sponsor of music festivals (NOS Alive and NOS Primavera Sound) and national football first division (Liga NOS). Their main key success factors are innovation and the quality of the services they offer to their consumers, which conjugated with their strong and diversified presence on the different sectors makes them a reference in the market. This is one of the most competitive markets in the world, and if companies want to thrive must have to strongly bet on innovation and come up to the market with new simple and practical solutions to customers. They are getting more and more exigent and the changes on their habits must always be taken into account. Therefore, this thesis consists on a marketing plan proposal for NOS to launch of a new feature for their TV boxes – pay-per-view – through an internal and external analysis, complemented by and implementation proposal. The last one composed by a marketing strategy and an operational plan with recommendations on the several axis of marketing-mix: product, price, placement and promotion.A NOS, NOS Comunicações S.A., é uma empresa privada de telecomunicações que opera no mercado português e se orgulha de ser “o melhor grupo de comunicações e entretenimento do país”. A empresa nasceu da fusão das duas maiores empresas de comunicação do país: na parte do serviço fixo (TV, telefone, internet, etc.) pela ZON; e na parte do serviço móvel (Telemóvel, internet móvel, etc.) pela Optimus. É uma empresa líder nos sectores em que atua. Para além das telecomunicações, a NOS é a principal empresa do mercado de exibição cinematográfica em Portugal (NOS Cinemas - com 62% de quota de mercado) e a principal patrocinadora de festivais de música (NOS Alive e NOS Primavera Sound) e da primeira divisão de futebol nacional (Liga NOS). Os seus principais factores de sucesso são inovação e a qualidade nos serviços que oferecem aos seus consumidores, que conjugado com a sua presença forte diversificada em todos os setores a torna numa empresa uma referência no mercado. Este é um dos mercados mais competitivos a nível mundial, e se as empresas pretendem prosperar têm que apostar fortemente na inovação e trazer para o mercado soluções cada vez mais simples e práticas para o consumidor. Estes são cada vez mais exigentes e as alterações nos seus hábitos de consumo devem ser sempre tidas em conta. Assim, esta tese consiste na proposta de um plano de marketing para a NOS no lançamento de uma nova funcionalidade nas suas boxes de TV- o pay-per-view- através de uma análise externa, interna e competitiva complementada com uma proposta de implementação. Esta última composta por uma estratégia de marketing e um plano operacional com recomendações nos vários eixos do marketing-mix: produto, preço, distribuição e comunicação

The use of bacteriophages to control biofilms

Este resumo faz parte de: Book of abstracts of the Meeting of the Institute for Biotechnology and Bioengineering, 2, Braga, Portugal, 2010. A versão completa do livro de atas está disponível em: http://hdl.handle.net/1822/1096

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

Influências de uma Gestão Participativa Escolar no cotidiano educacional no município de Bom Retiro do Sul/RS-Brasil

Esta monografia está circunscrita fundamentalmente às contribuições e interações de um processo de gestão participativa nas ações pedagógicas dos educandários municipais que possuem alunos do 1º ao 5º Ano do Ensino Fundamental, em regime integral de atividades, no município de Bom Retiro do Sul. O estudo descreve reflexões sobre a gestão participativa e seu contexto, oportunizando múltiplos olhares frente às suas relações sociais. Diante do exposto, o objetivo geral que norteou as linhas de ação oportunizou verificar a importância e os benefícios existentes na Gestão Participativa e no cotidiano escolar dos educandários que atendem os alunos em tempo integral. Utilizou-se como metodologia a pesquisa qualitativa, etnográfica, ocasional e de campo, com análise de informações coletadas via entrevista semi-estruturada. O estudo sobre Gestão Participativa fundamentou-se nas linhas de Paro (2000 e 2010), Lück (2010), Hora (1997), e Oliveira (1997), paralelamente oportunizando um resgate histórico baseado na legislação da Constituição Federal (1998), PNE (2014) e LDBN (1996), alicerçado nas abordagens de Ribeiro (1978), Reed (1997), Braverman (1987), Junquilho (2012), Bartnik (2012), e Chiavenato (2010). O contexto escolar transcende relações sociais pertinentes ao contexto, alicerçados nos estudos de Camargo (2006), Oliveira (1997), Ferreira (2008), Hora (1997), Faria (2009), Hattge (2006 e 2007) e Goldmeyer (2010). Após análise da realidade nos educandários, constatam-se, parcial e integralmente, as contribuições positivas que a gestão participativa aponta no processo significativo do ensino. As articulações de uma gestão participativa favorecem a qualidade educacional, tornando os educandários palco de situações significativas de ensino e de aprendizagem, oportunizando interações sociais pertinentes ao contexto no qual estão inseridas