959 resultados para Sei Whale


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Several unknown, abundant brominated compounds (BCs) were recently detected in the blubber of dolphins and other marine mammals from Queensland (northeast Australia). The BC were interpreted as potential natural products due to the lack of anthropogenic sources for these compounds. This study investigated whether some of the BCs accumulated by diverse marine mammal species are identical with natural BCs previously isolated from sponges (Dysidea sp.) living in the same habitat. Isolates from sponges and mollusks (Asteronotus cespitosus) were compared with the signals detected in the mammals' tissue. Mass spectra and gas chromatography retention times on four different capillary columns of the isolates from sponges and mammals were identical in all respects. This proves that the chemical name of the compound previously labeled BC-2 is 4,6-dibromo-2-(2'-dibromo)phenoxyanisole and that the chemical name of BC-11 is 3,5-dibromo-2-(3',5'-dibromo-2'-methoxy)phenoxyanisole. Using a quantitative reference solution of BC-2, we established that the concentrations of the brominated metabolies found in the marine mammals are frequently >1 mg/kg. The highest concentration (3.8 mg/kg), found in a sample of pygmy sperm whale (Kogia breviceps), indicates that BC-2 is a bioaccumulative, natural organohalogen compound. This is supported by the concentrations of the BCs in our samples being equal to the highest concentrations of anthropogenic BCs in any environmental sample. The quantitative determination of BC-2 in blubber of marine mammals from Africa and the Antarctic suggests that BC-2 is wide-spread. These results are direct proof that marine biota can produce persistent organic chemicals that accumulate to substantial concentrations in higher trophic organisms.

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Although largely solitary, humpback whales exhibit a number of behaviours where individuals co-operate with one another, for example during bubble net feeding. Such cases could be due to reciprocal altruism brought on by exceptional circumstances, for example the presence of abundant shoaling fish. An alternative explanation is that these behaviours have evolved through kin selection. With little restriction to either communication or movement, diffuse groups of relatives could maintain some form of social organization without the need to travel in tight-nit units. To try to distinguish between these hypotheses, we took advantage of the fact that migrating humpback whales often swim together in small groups. If kin selection is important in humpback whale biology, these groups should be enriched for relatives. Consequently, we analysed biopsy samples from 57 groups of humpback whales migrating off Eastern Australia in 1992. A total of 142 whales were screened for eight microsatellite markers. Mitochondrial DNA sequences (371 bp) were also used to verify and assist kinship identification. Our data add support to the notion that mothers travel with their offspring for the first year of the calf's life. However, beyond the presence of mother-calf/yearling pairs, no obvious relatedness pattern was found among whales sampled either in the same pod or on the same day. Levels of relatedness did not vary between migratory phases (towards or away from the breeding ground), nor between the two sexes considered either overall or in the north or south migrations separately. These findings suggest that, if any social organization does exist, it is formed transiently when needed rather than being a constant feature of the population, and hence is more likely based on reciprocal altruism than kin selection.

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Fruto do processo de harmonização contabilística vivido no seio da União Europeia, a partir de 2010, as entidades portuguesas passaram a dispor de um novo Sistema de Normalização Contabilística.(SNC). As entidades de menor dimensão podem, por opção, utilizar a Norma Contabilística e de Relato Financeiro para Pequenas Entidades(NCRF-PE), consagrada no SNC. Todavia, a Lei nº35/2010 de 2 de Setembro veio estabelecer um regime especial simplificado das normas e informações contabilísticas das microentidades aprovado pelo Discreto-Lei nº36-A/2011, de 9 de Março. Face á inexistência de estudos que versem sobre a transição para o normativo contabilístico das pequenas e microentidades, esta dissertação tem como objectivo conhecer o nível de preparação dos Técnicos Oficiais de Contas(TOC) aquando da adopção destes normativos,analisando o sei impacto ao nível do processo contabilístico e do relato financeiro.Para o efeito foi utilizada a técnica do questionário, cujas respostas indicam que a maioria dos TOC concorda com a existência destes normativos, considerando estar razoavelmente preparado a quanto da sua aplicação. O nível de preparação destes profissionais é tanto maior quanto maior o nível das habilitações académicas dos TOC bem como, a antiguidade na profissão. No que concerne ás mudanças ao nível de relato financeiro, destacam-se algumas rubricas do Balanço(Activos Tangíveis, Activos Intangíveis, Subsídios e Capital Próprio) onde os inquiridos consideram ter havido um maior impacto na sequência da adopção dos novos normativos.

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The aim of this study is to assess the levels of airborne ultrafine particles emitted in welding processes (tungsten inert gas [TIG], metal active gas [MAG] of carbon steel, and friction stir welding [FSW] of aluminum) in terms of deposited area in pulmonary alveolar tract using a nanoparticle surface area monitor (NSAM) analyzer. The obtained results showed the dependence of process parameters on emitted ultrafine particles and demonstrated the presence of ultrafine particles compared to background levels. Data indicated that the process that resulted in the lowest levels of alveolar deposited surface area (ADSA) was FSW, followed by TIG and MAG. However, all tested processes resulted in significant concentrations of ultrafine particles being deposited in humans lungs of exposed workers.

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25th Annual Conference of the European Cetacean Society, Cadiz, Spain 21-23 March 2011.

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25th Conference of the European Cetacean Society. Long-terms datasets on marine mammals: learning from the past to manage the future, Cadiz, Spain, 21-23 March 2011.

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26th Annual Conference of the European Cetacean Society, Galway, Ireland 26-28 March 2012.

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27th Annual Conference of the European Cetacean Society. Setúbal, Portugal, 8-10 April 2013.

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Jornadas "Ciência nos Açores- que futuro?", Biblioteca Pública e Arquivo Regional de Ponta Delgada, Largo do Colégio, Ponta Delgada, 7-8 de junho de 2013.

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Jornadas "Ciência nos Açores - que futuro?", Biblioteca Pública e Arquivo Regional de Ponta Delgada, Largo do Colégio, Ponta Delgada, 7-8 de junho.

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[...] viagem ao hotel infinito de Hilbert. Sei que na atual crise económica não é prudente qualquer devaneio turístico, mas como o prometido é devido, eis-me a tentar explicar um desafio que ficou em banho-maria desde dezembro e que consistia em resolver o seguinte enigma: se um hotel tiver um número infinito de quartos e cada quarto possuir um número infinito de janelas, será que existem mais quartos do que janelas? [...].

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Dissertação de Mestrado em Gestão e Conservação da Natureza.

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Dissertação de Mestrado em Estudos Integrados dos Oceanos.

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Tese de Doutoramento, Ciências Económicas e Empresariais (especialidade de Economia), 18 de Junho de 2015, Universidade dos Açores

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Dissertação de Mestrado, Património, Museologia e Desenvolvimento, 25 de Fevereiro de 2016, Universidade dos Açores.