Marine ornamental species from European waters: a valuable overlooked resource or a future threat for the conservation of marine ecosystems?

The worldwide growth of the marine aquarium market has contributed to the degradation of coral reef ecosystems. Enforcing the legislation on importing ornamental species has led some European traders to concentrate on local species. Portugal is used as a case study of marine ornamental fish and invertebrate collection in European waters. One hundred and seventy two species occurring in Portuguese waters (mainland, the Azores and Madeira archipelagos) were considered as potential targets for the marine aquarium industry, some of which are already traded on a regular basis (e.g. Clibanarius erythropus, Lysmata seticaudata, Cerithium vulgatum, Hinia reticulata and Ophioderma longicauda). To ensure appropriate management and conservation of these resources, the following options have been evaluated: banning the harvest and trade of all marine ornamental species from European waters; creating sanctuaries and "no take zones"; issuing collection permits; creating certified wholesalers; implementing the use of suitable gear and collecting methods; setting minimum and maximum size limits, establishing species-based quotas; protecting rare, or "key stone" species and organisms with poor survivability in captivity; establishing closed seasons; culturing ornamental organisms; and creating an "eco-fee" to support research and management. Establishing this sustainable alternative fishery may help minimise the economical and social impacts caused by the crash of important food fisheries in Portugal and other European and West African countries

Facultative secondary lecithotrophy in the megalopa of the shrimp Lysmata seticaudata (Risso, 1816) (Decapoda : Hippolytidae) under laboratory conditions

Certain decapod crustaceans can catabolize internal reserves to undergo partial or full larval development. This feature is termed secondary lecithotrophy, if energy used results from plankton derived organic matter accumulated Ig earlier larval stages. The present work reports the ability of Lysmata seticaudata megalopa to moll to the first juvenile stage in the absence of food. Unlike previous records of secondary lecithotrophy displayed by nonfeeding last larval stages of hermit crabs and spiny lobsters, the megalopa of L. seticaudata retains its feeding capacity. This is the first time such a feature has been reported in decapods, and the term facultative secondary lecithotrophy is proposed. The build up of energy reserves continues during the last zoeal stage of L. seticaudata, with starved zoea IX failing to molt to megalopa. Energy reserves that enable starved megalopa to molt to juvenile seem to be partially depleted, with starved juveniles produced either from, starved or fed megalopae being unable to molt to the next juvenile stage. The longer resistance of starved juveniles produced from fed megalopae (nine days), compared to that of starved juveniles produced from starved megalopae (five days), indicates that some energy reserves may pass to juvenile, not being totally depleted at metamorphosis.info:eu-repo/semantics/publishedVersio

Additive Manufacturing of Resettable-Deformation Bi-Stable Lattices Based on a Compliant Mechanism

Metamaterials allow for the possibility to design and fabricate new materials with enhanced me- chanical properties, through the use of additive manufacturing. There are some certain materials’ struc- tures that exhibit excellent properties to withstand externally applied forces. One example of this type of structure is a bi-stable switching mechanism which can regain its original position, after being sub- mitted to a compressive force. This kind of structure should be flexible and strong since it needs to undergo a certain deflection. Another important aspect that was addressed in this work is the structure’s geometry, because of the effect that it has on flexibility. Therefore, this thesis will focus on the proper study, design, 3D printing, and mechanical characterization of a novel unitary compliant bi-stable struc- ture, and its use to build two larger cellular compliant bi-stable structures, a four-cell and a multicell structure, using the unitary one as a building block. All structures were designed in the CAD software Fusion 360 and fabricated with Polylactic Acid filament using the Fused Filament Fabrication process. The fabricated structures were submitted to compressive tests, from where Force vs. Displacement plots were obtained. These results proved that the multicell structure was the stiffest, since it required higher compressive force to perform its function, when compared to the other two structures. The conducted tests were important to check the behavior of each structure while being compressed, where both struc- tures that had more than one cell showed a layered switching behavior. Also, the tests were important to check if the position recovery of the structures was possible to achieve, which was observed in all of them. After the compressive tests, all structures were also submitted to repetitive solicitation tests, to study their repeatability behavior. These results envisage the successful application of these mechanisms towards their implementation in microelectromechanical systems.Os metamateriais permitem fabricar novos materiais com propriedades mecânicas aprimoradas, através do uso de manufatura aditiva. Existem algumas estruturas de determinados materiais que apresentam excelentes propriedades para resistir às forças externas aplicadas sobre eles. Um exemplo deste tipo de estrutura é um mecanismo complacente biestável que pode recuperar a sua posição original, após ser submetido a uma força de compressão. Este tipo de estrutura precisa de ser flexível e forte, porque é projetado para sofrer uma certa deflexão. Outro aspeto importante que foi abordado neste trabalho é a geometria da estrutura, devido ao efeito que esta tem na flexibilidade. Portanto, esta dissertação concentrar-se-á no estudo adequado, desenho, impressão 3D e caracterização mecânica de uma nova estrutura complacente biestável unitária, e o seu uso para construir duas estruturas celulares complacentes biestáveis, uma de quatro células e outra multicelular, usando a estrutura unitária como bloco de construção. Todas as estruturas foram desenhadas no software de CAD Fusion 360 e fabricadas com filamento de Ácido Poliláctico usando o processo de Fabricação com Filamento Fundido. As estruturas fabricadas foram submetidas a ensaios de compressão, de onde foram obtidos gráficos de Força vs. Deslocamento. Estes resultados comprovaram que a estrutura multicelular era a mais rígida, porque necessitou de uma maior força compressiva para desempenhar a sua função. Os testes realizados foram importantes para analisar o comportamento de cada estrutura durante a compressão, onde ambas as estruturas multicelulares apresentaram um comportamento de transição camada a camada. Além disso, os testes foram também importantes para verificar se a recuperação da posição das estruturas era possível, o que foi observado para todas. Após os ensaios de compressão, todas as estruturas foram submetidas a ensaios de solicitação repetitiva, para estudar o seu comportamento de repetibilidade. Estes resultados vislumbram o sucesso da implementação destes mecanismos em sistemas microelectromecânicos

Rendimento económico e produtivo da soldadura MAG com fio sólido vs. fio fluxado

Na construção soldada, devido ao contínuo aumento dos custos envolvidos com a mão-de-obra e consumíveis, há cada vez mais necessidade, por parte das empresas e dos seus responsáveis, de se poder determinar, com o máximo rigor possível, qual a técnica mais adequada, com o menor custo associado. Ajustando convenientemente os parâmetros e consumíveis de soldadura ao trabalho a realizar, conseguem-se consideráveis reduções dos montantes envolvidos. A competitividade entre empresas é grande e, na maioria dos casos, a diminuição desses custos conduz a um maior sucesso comercial, traduzindo-se numa actualização e optimização dos recursos disponíveis. Teve-se como objectivo, comparando dois processos de soldadura semi-automática MAG (GMAW) e soldadura por fios fluxados (FCAW), determinar qual o mais vantajoso do ponto de vista económico-produtivo. No caso do presente trabalho, efectuaram-se diversos ensaios de soldadura, utilizando materiais nas qualidades e espessuras características da média/pesada construção metalomecânica. Recorreu-se aos processos de soldadura GMAW e FCAW, ou seja, empregando fio consumível sólido e fio consumível fluxado, protecção por gás activo de uma mistura de árgon e dióxido de carbono e efectuando uma soldadura de canto na posição ao baixo nos diversos ensaios através da técnica passe simples e passes múltiplos. Concluiu-se que quando se pretende utilizar técnicas de passe múltiplo onde uma elevada velocidade de soldadura é requerida, o processo FCAW é o mais indicado

Correct diagnosis of early zoeal stages of Athanas nitescens (Leach, 1814) (Decapoda, Caridea, Alpheidae) using laboratory-raised larvae

The morphology of the first two larval stages of Athanas nitescens (Leach, 1814), reared under laboratory conditions, is redescribed. The present data are compared with previous works, since a clarification of the morphological characters of the first two larval stages of A. nitescens is needed, in order to avoid misidentification of these stages in the future.info:eu-repo/semantics/publishedVersio

Decapod crustaceans associated with the snakelock anemone Anemonia sulcata. Living there or just passing by?

The present work identifies the decapod crustaceans that associate with Anemonia sulcata on the southwestern Atlantic coast of Portugal and characterises their host use pattern. It determines whether the anemone is monopolised by any species, resulting in the exclusion of conspecifics or other decapods and, under laboratory conditions, it evaluates the degree of association between each species and A. sulcata. From all sampled anemones, 79% harboured at least I decapod crustacean, with the majority displaying either one or two specimens (32 and 24%, respectively). The most abundant species were the shrimp Periclimenes sagittifer and the crab Inochus pholangium (representing 36 and 3 1 % of collected specimens, respectively), which displayed lasting associations and were commonly recorded among the tentacles of the host. The species Eualus occultus, E. complex cranchii, Clibanarius erythropus, Maja brachydactyla, Pilummus hirtellus and Polybius (Necora) puber displayed short-term associations, were mainly present on the substratum near the base, and avoided the tentacles of A. sulcata. Periclimenes sagittifr and I. phalangium were only recorded alone or in heterosexual pairs, appearing to efficiently defend their host against conspecifics. The majority of recorded species only seem to temporarily associate with A. sulcata, in order to seek protection from predators when other shelters are unavailable.info:eu-repo/semantics/publishedVersio

Kleptoplast photoacclimation state modulates the photobehaviour of the solar-powered sea slug Elysia viridis.

Some sacoglossan sea slugs incorporate intracellular functional algal chloroplasts (kleptoplasty) for periods ranging from a few days to several months. Whether this association modulates the photobehaviour of solar-powered sea slugs is unknown. In this study, the long-term retention species Elysia viridis showed avoidance of dark independently of light acclimation state. On the contrary, Placida dendritica, which shows non-functional retention of kleptoplasts, showed no preference over dark, low or high light. High light acclimated (HLac) E. viridis showed a higher preference for high light than low light acclimated (LLac) conspecifics. The position of the lateral folds (parapodia) was modulated by irradiance, with increasing light levels leading to a closure of parapodia and protection of kleptoplasts from high light exposure. Furthermore, closure of parapodia occurred at higher irradiances in HLac E. viridis. Our results strongly indicate that kleptoplasts photoacclimation state modulates the photobehaviour of the solar-powered sea slug E. viridis

Preparação para performance de bass colors para contrabaixo acústico e ableton live

Este texto aborda a utilização do programa Ableton Live como ferramenta de estudo e sua aplicabilidade na preparação da performance musical ao contrabaixo. Pretende-se apresentar uma possibilidade didática para o uso da ferramenta no ensino e na preparação para a performance da obra Bass Colors de Ricardo Bigio. A problemática do trabalho reside em direcionar as escolhas que o contrabaixista contemporâneo tem diante da pluralidade das possibilidades de execução e de materiais didáticos existentes para o contrabaixo acústico, particularmente aqueles voltados para os séculos XX e XXI

Current trends in the traceability of geographic origin and detection of species-mislabeling in marine bivalves

Marine bivalves are increasingly consumed worldwide, with their complex supply chain being particularly prone to fraud. This scenario drives economic losses and is a threat to public health, with multiple recent food worries driving consumers to demand more transparency and information on the seafood they buy. To increase consumers confidence in bivalves and enforce current legislation, robust tools are needed to fight species mislabeling and confirm the place of origin of bivalves being traded. The present study provides a critical overview based on a databases search, over the traceability of geographic origin and detection of species-mislabeling in marine bivalves, summarizing the tools currently available to confirm claims on these topics along the supply chain. We also identify current trends on the use of tools, pinpoint which countries contribute to advance the state of the art on these topics, and highlight the bivalve groups/species being more commonly surveyed. The most used tools to expose species mislabeling in marine bivalves are DNA and fatty acid analysis, while elemental analysis is the most commonly employed approach to confirm their geographic origin. Stable and unstable isotope analysis, as well as metabolomics, are also starting to be increasingly used to verify species authenticity and provenance in marine bivalves. Further studies are still needed to identify annual/seasonal variations and determine if these can be a constraint for the optimization of protocols to fight fraudulent practices. The implementation of an open global database to allow realtime data comparison will be paramount to advance the state of the art.publishe

Diversidade de macrofungos na comparação entre tipos de exploração florestal

O estudo da diversidade de macrofungos nos ecossistemas florestais é dificultado pela parcimónia com que muitas espécies frutificam e pelos imprevistos que surgem ao longo dos anos. O presente estudo é a primeira implementação duma abordagem comparativa, baseada na observação em paralelo de parcelas representativas de diferentes modelos de povoamento (sobreiral de referência, com agricultura ou com pastagem, pinhal, misto). Da amostragem de 94 espécies feita na Primavera e Outono de 2003 no concelho de Chamusca, verificou-se que a diversidade de macrofungos era relativamente baixa nos modelos com agricultura ou pastagem — neste último praticamente sem frutificação de espécies ectomicorrízicas, predominantes em todos os outros modelos. As parcelas mistas não apresentaram esporóforos característicos de pinhal, antes parecendo uma réplica dos sobreirais de referência. A maior parte das espécies não eram partilhadas entre modelos de povoamento, sugerindo que um maior número de parcelas permite, em prazo curto, captar mais eficientemente a diversidade existente