995 resultados para Scientific experiments


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Assumindo a sociedade atual o paradigma do desenvolvimento sustentável como modelo capaz de garantir uma gestão equilibrada dos recursos atuais que não comprometa o futuro das futuras gerações, é fundamental compreender o instrumento da Agenda 21 Local (A21L), ferramenta saída da Conferência do Rio, em 1992, que se apresenta como uma resposta internacional aos objetivos da sustentabilidade. Ao constituir-se como país signatário da Declaração do Rio, Portugal assumiu o compromisso de cooperar internacionalmente para a aplicação deste instrumento, no esforço comum de unir a proteção do ambiente com o desenvolvimento económico e social. Verifica-se que a resposta de Portugal, em matéria de A21L, foi pouco conseguida, marcada por um arranque ténue, desconcertado e disperso a que acresce o caráter dúbio que caracterizou a natureza dos primeiros processos e que, no quadro internacional, atira Portugal para o grupo de países europeus que mais tardiamente conseguiram responder ao apelo da comunidade internacional no que se refere à implementação de A21L. Neste âmbito, esta dissertação visa aprofundar o conhecimento cientifico sobre este instrumento no quadro das experiências de Agenda 21 Local implementadas no território português. O trabalho procurou examinar os objetivos, características e resultados dos processos de Agenda, dando atenção aos elementos individuais que marcaram cada um e, igualmente, avaliando as repercussões que estes tiveram no todo nacional. O estudo incidiu na dinâmica espaciotemporal das Agendas21L, no território nacional, e na análise integrativa de indicadores físicos, sociais e económicos que permitiram compreender as especificidades e os contrastes verificados nos processos implementados e desenvolvidos. Na investigação não foram, igualmente, negligenciadas questões históricas, políticas e culturais, sabendose da importância que estes vários domínios configuram no caso português. O trabalho contou com uma investigação assente na seguinte metodologia: i) Revisão da literatura e recolha de dados bibliográficos sobre a temática da Agenda 21 Local; ii) Levantamento de informação, através de um inquérito por questionário, dirigido a todas as localidades do País, onde decorrem Agendas 21 Local, a fim de complementar informação já processada; iii) Pesquisa direta de dados no terreno que envolveu a utilização de procedimentos de teor quantitativo (inquérito por questionário) e de teor qualitativo (entrevistas), relativamente ao caso de estudo (Agenda 21 Local de Mindelo); iv) Tratamento e análise dos resultados obtidos através da confrontação da perspetiva teórica com a prática com a consequente elaboração de conclusões fundamentadas pela confrontação dos dados com as hipóteses. Para além de se tratar do caso pioneiro de A21L com início no poder mais próximo do cidadão (respeitando um dos princípios inerentes a este instrumento – o princípio da subsidiariedade), afirmou-se, igualmente, como um caso de referência em matéria de coesão e mobilização dos cidadãos locais para os problemas locais existentes. Os resultados empíricos da investigação identificam uma série de dificuldades que condicionaram o arranque e progresso das A21L. Desde logo, a inabilidade dos poderes políticos locais em trabalharem com um modelo que rompe com as típicas e tradicionais formas pré-concebidas de fazer política, isto é, com as práticas instituídas dos políticos fazerem “política” para os cidadãos e não “com” os cidadãos. O próprio desconhecimento do poder político local quanto à natureza de um processo de A21L que evidenciou inaptidão, impreparação e até embaraço para lidar com este instrumento, resultando na necessidade, na grande maioria dos processos desenvolvidos, de serem acompanhados por entidades externas que cooperaram na sua dinamização. Acresce que a nova dinâmica, subjacente à A21L, que desafia os governos locais a mobilizar a participação generalizada dos cidadãos e apela à participação de novos atores (associações, grupos de interesse, ONG e atores sociais, em geral) para a definição de estratégias de desenvolvimento local, não é totalmente aceite pelos vários poderes locais que, não raras vezes, menosprezam a importância dos cidadãos nos momentos de tomada de decisão. A falta de empenho do governo central, em matéria de sustentabilidade, que negligenciou, numa primeira etapa, a figura do poder central na assessoria às entidades locais cerceou o país da existência de uma campanha nacional para a afirmação deste instrumento. A falta/insuficiência de recursos financeiros como resultante da ausência de apoios estatais e a dificuldade na obtenção de fundos da União Europeia configurou-se como um entrave à promoção dos processos ficando as entidades locais e regionais incapazes de ultrapassar a falta de meios imprescindíveis para o desenvolvimento da A21L. O próprio desconhecimento generalizado dos cidadãos sobre a A21L afigura-se como um estigma ao sucesso de qualquer processo com as caraterísticas de um instrumento A21L visto que a participação dos cidadãos é condição sine qua non para a sua operacionalização. Neste quadro, e olhando o futuro, urge a necessidade das autoridades locais criarem modelos de autofinanciamento capazes de garantir a criação, funcionamento e manutenção de infraestruturas económicas e sociais subjacentes aos programas de A21L, assim como o dever do poder político em reforçar a importância da função da informação e da mobilização dos cidadãos em prole do desenvolvimento sustentável, ações indispensáveis para a execução das políticas inerentes à A21L.

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This is a research project by practice, which firstly develops a new material invention derived from natural fibres extracted from waste pineapple leaves; secondly it articulates the contemporary designer’s role in facilitating sustainable solutions through: Insights from my own material invention, PiñatexTM, which integrates the materiality of design with the immateriality of concepts and values Developing a visual model of mapping I began with these questions: ‘What are the challenges in seeking to make a new and sustainable material from the waste products of pineapple agriculture in the Philippines?’ and ‘How can a design practice link elements of materiality (artifacts) with immaterial elements (value systems) in order to improve sustainable social and economic development?’ Significant influences have been the work of Papanek1 (2003), Hawken2 (1999) and Abouleish3 (2008) and in particular the ethical business model initiated by McDonough and Braungart in Cradle to Cradle®4 (2002). My own research project is inspired by the Cradle to Cradle® model. It proposes the development of a new material, PiñatexTM which is derived from natural fibres extracted from waste pineapple leaves and could be used in a wide variety of products that are currently fabricated in leather or petroleum-based materials. The methods have comprised: Contextual reviews; case studies (SEKEM, Cradle to Cradle® and Gawad Kalinga); practical experiments in the field of natural fibres, chemistry, product development, manufacturing and prototyping, leading to an invention and a theoretical model of mapping. In addition, collaboration has taken place across scientific, technological, social, ecological, academic and business fields. The outcome is a new material based on the synchronicity between the pineapple fibres, polymers, resins and coatings specially formulated. The invention of the new material that I developed as a central part of this research by practice has a patent in the national phase (PCT/GB 2011/000802) and is in the first stages of manufacturing, commercial testing and further design input (Summer 2014). The contribution to knowledge is firstly the material, PiñatexTM, which exhibits certain key qualities, namely environmentally non-toxic, biodegradable, income-generating potential and marketability. This is alongside its intrinsic qualities as a textile product: aesthetic potential, durability and stability, which will make it suitable for the accessories, interiors and furnishing markets. The theoretical mapping system Upstream and Downstream forms a secondary contribution.

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Vector sensors measure both the acoustic pressure and the three components of particle velocity. Because of this, a vector sensor array (VSA) has the advantage of being able to provide substantially higher directivity with a much smaller aperture than an array of traditional scalar (pressure only) hydrophones. Although several, most of them theoretic, works were published from early nineties, only in the last years due to improvements and availability of vector sensor technology, the interest on field experiments with VSA increased in the scientific community. During the Makai Experiment, that took place off the coast of Kauai I., Hawaii, in September 2005, real data were collected with a 4 element vertical VSA. These data will be discussed in the present paper. The acoustic signals were emitted from a near source (low frequency ship noise) and two high frequency controlled acoustic sources located within a range of 2km from the VSA. The advantages of the VSA over traditional scalar hydrophone arrays in source localization will be addressed using conventional beamforming.

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All the evidence indicates that distillation and liqueurs preparation began in Monchique mountain because this place was pointed as a possible capital of the oldest population of Algarve and an important Arabic village (Barreto, 1972: 19). It was possible to find lots of vestiges like the alembic produced by Arabic population near the X century (Telo, 1988: 77). Traditionally the Algarvian people produce the Arbutus unedo L., fig, carob, grape distillates. At the same time they produce liqueur-using maceration of parts of plants or fruits in some kinds of distillates. Most of the work about Algarvian distillates started by studying the basic compounds of Arbutus unedo spirits by gas chromatography (GC) and mass spectrometry (MS) as well as other physical-chemical properties. In a second phase aged distillates were studied by their phenolic compounds evolution using high resolution liquid chromatography (HPLC). Volatile compounds of traditional liqueurs were identified by head space micro extraction solid phase (HE-SPME) and also analysed by gas chromatography mass spectrometry (GC-MS) and when possible confirmed with standards. Total phenols were determined by Folin-Ciocalteur method. Flavenoids were studied by high performance liquid chromatography (HPLC). Sensorial analysis was also done in every drink studies. The results showed that the arbutus distillate doesn’t present a high level of methanol according to the current legislation. The excesses of acidity or ethyl acetate present normal values when the fermentation is well done (Galego, et al. 1995: 341; Galego, et al. 1995: 685). During the aging process, the colour of spirits tend to become darker, the colour changes occurred more rapidly in the arbutus spirits located in cellars with higher temperatures (Galego, et al. 2001: 432). In the sensory evaluation of samples aged during 12 months into 50 L medium toasting level oak wood barrels, panellists considered that samples of arbutus spirit had too much wood flavour and they were not able to detect the characteristic aroma of arbutus fruit (Galego, et al., 2001: 183). Differences in liqueurs were observed using HS-SPME-GC, HS-SPME-GC-MS or HPLC analysis and this observation was confirmed by a sensorial panel (Galego, et al. 2003: 60).

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Tese de dout., Ciências e Tecnologias das Pescas, Faculdade de Ciências do Mar e do Ambiente, Univ. do Algarve, 2003

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Although overfishing is a concern for many fish stocks, it was for a long time only associated with commercial fishing exploitation, with less or no attention being given to the recreational fisheries. Recent research has shown however that the impact of recreational fishing on particular species can be considerable, and that the recreational harvest needs to be taken into account if fisheries are to be accurately assessed and effectively managed. In Portugal, the first recreational fishing regulations were only recently implemented. However, mirroring other European countries, regulations lacked scientific support, and specific knowledge of the activity was limited to a few studies with limited coverage. This thesis aimed to characterize the biological and socioeconomic aspects of the recreational shore angling activity in southern Portugal, to investigate whether the regulations in place were adequate and effective, and to provide recommendations for improved management and conservation of the inshore fisheries resources. A combined aerial-roving survey was conducted to gather data on fishing effort, catch, fishing trips and socioeconomic aspects (including anglers’ perceptions of regulations) of the recreational angling activity. The analysis of anglers’ catches suggested that compliance with daily bag limits was high, with less than 0.5% of creels exceeding the 10 kg angler-1 day-1 bag limit. Overall, 11.5% of the retained fishes were undersized, but non-compliance with minimum size limits was found to be high for some species (e.g. seabass, 73% undersized). In terms of the impact of recreational shore angling, the total estimated catches corresponded to less than 1% of the commercial landings for the same period (shared species). However, shore angling catches for white sea bream (Diplodus sargus) were found to be considerable, corresponding to 65% of the commercial landings (39.4% of total catch). In terms of anglers’ perceptions about the recreational fishing regulations in Portugal, the present study has shown that the majority of anglers accepted the existence of some kind of SRF regulations, but in general there was a partial or total disagreement with the recreational fishing restrictions recently put in place. Most anglers perceived themselves as not being involved in the decision-making process and claimed that some restrictions lacked a meaningful rationale (e.g. prohibition of fishing from piers/jetties). Fishers’ awareness with regard to specific aspects of the restrictions (such as the rationale for minimum size limits) was found to be very limited. During the same period, catches from sport fishing competitions were examined to test for differences with the recreational activity in terms of catches, and evaluate long term trends in catch and mean size of fish. Catches of the sport fishing competitions were found to be different from those observed for recreational fishing, being dominated by different species (e.g. garfish, mullets), and suggesting different fishing strategies of the the two types of anglers. High percentages of undersized fish were observed to be captured (and retained) during the competitions (in particular seabass, with 100% undersized), probably as a result of a single allowable minimum size (AMS) of 15 cm for all species in use in competitions. Lastly, catch and release fishing experiments were carried out to assess post-release mortality of three recreationally important species: two banded sea bream Diplodus vulgaris; black sea bream Spondyliosoma cantharus; and gilthead sea bream Sparus aurata. Post-release mortalities were found to be low (0-12%). The main predictor of mortality for Sparus aurata was anatomical hooking location, with 63% of the fishes that died being deeply hooked. The results support the release of fish, either from mandatory (e.g. minimum landing sizes) or voluntary practices. In summary, this thesis has demonstrated that the impact of recreational fishing for particular species is significant and needs to be taken into account for more effective management and stock assessment purposes. It has also highlighted several management issues that should be addressed in order to promote more adequate regulations in the future and prevent noncompliance issues. A periodic monitoring of the recreational fishing activity including all fishing modes (i.e. spear fishing, boat, and shore angling) would also be beneficial to ensure a timely knowledge on the global recreational fishing activity and support future management actions.

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Dissertação de mestrado, Biologia Marinha, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015

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The following paper deals with an automatic text classification method which does not require training documents. For this method the German Subject Heading Authority File (SWD), provided by the linked data service of the German National Library is used. Recently the SWD was enriched with notations of the Dewey Decimal Classification (DDC). In consequence it became possible to utilize the subject headings as textual representations for the notations of the DDC. Basically, we we derive the classification of a text from the classification of the words in the text given by the thesaurus. The method was tested by classifying 3826 OAI-Records from 7 different repositories. Mean reciprocal rank and recall were chosen as evaluation measure. Direct comparison to a machine learning method has shown that this method is definitely competitive. Thus we can conclude that the enriched version of the SWD provides high quality information with a broad coverage for classification of German scientific articles.

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Senior thesis written for Oceanography 445

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The book explores the aesthetic and political implications of the relationship between magic and mimesis in the work of those early twentieth-century writers, artists and filmmakers who were most self-consciously experimental, including James Joyce, Ezra Pound, Dziga Vertov and Sergei Eisenstein.

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To be legitimate, research needs to be ethical, methodologically sound, of sufficient value to justify public expenditure and be transparent. Animal research has always been contested on ethical grounds, but there is now mounting evidence of poor scientific method, and growing doubts about its clinical value. So what of transparency? Here we examine the increasing focus on openness within animal research in the UK, analysing recent developments within the Home Office and within the main group representing the interests of the sector, Understanding Animal Research. We argue that, while important steps are being taken toward greater transparency, the legitimacy of animal research continues to be undermined by selective openness. We propose that openness could be increased through public involvement, and that this would bring about much needed improvements in animal research, as it has done in clinical research.

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In this work we solve Mathematical Programs with Complementarity Constraints using the hyperbolic smoothing strategy. Under this approach, the complementarity condition is relaxed through the use of the hyperbolic smoothing function, involving a positive parameter that can be decreased to zero. An iterative algorithm is implemented in MATLAB language and a set of AMPL problems from MacMPEC database were tested.