130,497 research outputs found
Pesca artesanal na Baía Norte de Florianópolis: capturas, esforço de pesca, problemática e possíveis soluções.
No full textTCC(graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Biológicas. Biologia.A Baía Norte de Florianópolis se localiza no litoral central do Estado de Santa Catarina (27° 23 ' - 27° 25S, 48° 33 ' - 48° 30'O) e se caracteriza como um ambiente estuarino de alta produtividade. É uma região utilizada por diversas espécies que se encontram em período reprodutivo e abriga espécies ameaçadas de extinção como a tartaruga Chelonia mydas e uma população residente de golfinhos da espécie Sotalia guianensis. Acompanhamos o trabalho de 8 pescadores, distribuídos em diferentes comunidades pesqueiras da ilha de Santa Catarina e do continente (Sambaqui, Saco Grande, Caieira e Fazenda da Armação), com o objetivo geral de analisar a pesca artesanal nessa região com ênfase nas capturas, esforço de pesca, problemática da atividade e possíveis soluções. Através de saídas embarcadas e entrevistas realizadas no período de junho de 2006 até junho de 2008, buscamos conhecer a estrutura organizacional das instituições envolvidas na pesca artesanal, as características sócioeconômicas e operacionais dos pescadores, o esforço pesqueiro aplicado à Baía Norte, sua produção pesqueira e o comportamento destes em relação a ocupação do espaço e otimização dos processos pesqueiros. A Captura por Unidade de Esforço (CPUE) foi utilizada para as análises da produção pesqueira. Através da teoria de forrageamento ótimo, buscamos identificar o comportamento e a percepção dos pescadores em relação às estratégias de pesca e sua otimização. Após consultas a diversas instituições governamentais e não governamentais, verificamos que o governo terceirizou serviços administrativos ligados a pesca e os custos foram repassados aos pescadores artesanais. Entrevistas com 43 pescadores mostraram que a idade média é de 41 anos (d.p.=12,67 anos) e estes começam a pescar com idades entre 7 e 12 anos. Possuem em média 1,53 filhos (d.p.=1,35 filhos) e renda variando entre 1 e 3 salários mínimos (média de R$522,49 e d.p.=226,89). Porém, a variação desta renda é grande e 65% dos pescadores analisados possuem outra fonte de renda. Identificamos junto a SEAP/PR 156 embarcações (Bateiras, Botes e Baleeiras) atuando na Baía Norte e cerca de 500 pescadores artesanais executando as artes de pesca de Cerco, Caceio, Fundeio e Arrasto. Nas 52 saídas realizadas, acompanhamos a captura de 4912Kg de pescado, onde para isso foram utilizados um total de 581306m2 de rede durante 628 horas. O Caceio foi a arte mais executada, 58,18% das pescarias, o Arrasto a arte que apresentou a maior CPUE (642,52g/m2/hora), o Cerco a arte com a maior média de captura (105,91kg e d.p.=470,61kg) e o Fundeio a arte de pesca que capturou as espécies não-alvo mais ameaçadas. Na composição do pescado estão 34 espécies de peixes, 3 de crustáceos e 1 de réptil, sendo as principais espécies capturadas Litopenaeus schimitii, Trichiurus lepturus, Micropogonias furnieri, Mugil platanus. e Menticirrhus americanus. Entre as espécies não alvo capturadas estão 5 indivíduos de Chelonia mydas. Através da análise comportamental dos pescadores e a aplicação do modelo de forrageamento ótimo, verificamos que existe um revezamento de artes de pesca e uma forte relação entre a distância dos pontos de pesca e o tempo gasto nos processos pesqueiros. Assim, verificamos que os pescadores da Baía Norte possuem Raphael B. M. Aggio X um comportamento funcional e estratégico em busca de maiores capturas e, conseqüentemente, maior retorno financeiro. A crise na qual o setor pesqueiro mundial se encontra aumenta a importância da pesca artesanal como principal fonte de pescado e dependente de novas medidas conservacionistas. Além disso, estudos recentes deixam cada vez mais clara a interdependência entre diferentes ecossistemas, mostrando que os resultados locais podem e devem ser levados para o nível global. Sendo assim, os resultados apresentados neste estudo devem receber grande atenção dos órgãos competentes para o desenvolvimento de práticas conservacionistas participativas que solucionem a problemática aqui apresentada
A novel polymerase chain reaction (PCR) - Denaturing Gradient Gel Electrophoresis (DGGE) for the identification of Micrococcaceae strains involved in meat fermentations. Its application to naturally fermented Italian sausages
No full textnew molecular method consisting of polymerase chain reaction (PCR) amplification and denaturing gradient gel electrophoresis (DGGE) of a small fragment from the 16S rRNA gene identified the Micrococcaceae strains isolated from natural fermented Italian sausages. Lactic acid bacteria, total aerobic mesophilic flora, Enterobacteriaceae and faecal enterococci were also monitored. Micrococcaceaea control strains from international collections wereused to optimise the method and 90 strains, isolated from fermented sausages, were identified by biochemical tests and PCR-DGGE. No differences were observed between the methods used. The results reported in this paper provethat Staphylococcus xylosus is the main bacterium involved in fermented sausage production, representing, from the tenth day of ripening, the only Micrococcaceaea species isolated. (C) 2001 Elsevier Science Ltd. All rights reserved
An application of PCR-DGGE analysis to profile the yeast populations in raw milk
No full textFour different zones from the Friuli Venezia Giulia region, North East of Italy, were sampled for the study of the yeast biodiversity in raw milk. Samples were analysed by traditional methods to isolate different yeast strains that were subjected to identification by sequencing the D1-D2 domains of the 26S rRNA gene. Twelve different species of yeast were identified, six of them belonging to the genera Candida and two to the genera Kluyveromyces. The identified strains were then used for the optimization of a method based on polymerase chain reaction and denaturing gradient gel electrophoresis that was used for a direct monitoring of the populations in the samples. Applying the method to the DNA extracted directly from the raw milk samples, new bands appeared in the gel underlining a different bio-diversity in respect to the traditional method. The approach described is a powerful and reliable tool to monitor directly yeast ecology in milk and milk products without the need of traditional isolation and it could be used to follow specific populations to prevent spoilage or to control contamination. © 2002 Published by Elsevier Science Ltd
Studio dell’evoluzione della flora microbica durante la fermentazione di salami mediante l’impiego della tecnica elettroforetica DGGE (Denaturing Gradient Gel Electrophoresis)
No full textMeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Purinergic P2X neuro-neuronal transmission underlies the 5HT3 receptor mediated inhibition of rabit distal colon propulsion.
No full textFlavonoids, vascular function and cardiovascular protection
No full textA large body of evidence supports that the dietary intake of polyphenols - particularly of flavonoids and the specific class of flavonoids named flavanols - might be able to exert some beneficial vascular effects and reduce the risk for cardiovascular morbidity and mortality. The review of epidemiological and mechanistic studies supports the role of flavonoids, particularly cocoa and tea flavanols, in protecting the cardiovascular system against cardiovascular disease. Nevertheless, flavonoids are an heterogeneous group of natural molecules differently represented in fruit and vegetables and definitive data on cardiovascular benefits are lacking. The weakness of the available data include few and very small studies, no crossover designed studies and a wide range of dose and type of flavonoids tested. Thus, although flavonoid-rich foods and beverages are likely to protect cardiovascular system, further research is needed to characterize the mechanism of action on flavanol-rich foods. Long-term clinical trials are also needed to definitively clarify the benefits deriving from long-term consumption of flavanol-rich foods, particularly focussing on the lowest effective levels as well as synergism or antagonistic actions between different classes of flavonoids commonly found in foods
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