Browsing by Issue Date, starting with "2011-03"
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- A new natural spiro heterocyclic compound and the cytotoxic activity of the secondary metabolites from Juniperus brevifolia leavesPublication . Moujir, Laila M.; Seca, Ana M. L.; Araujo, Liliana; Silva, Artur M. S.; Barreto, Maria do CarmoA new natural spiro compound 3,4-dehydrotheaspirone 1 and the known arctiol [1β,6α-dihydroxy-4(14)-eudesmene] 2 were isolated from Juniperus brevifolia. Arctiol is reported for the first time in the Juniperus genus. Their structures were established by 1D, and 2D NMR and MS spectra. Antimicrobial and cytotoxic activities of 1 and several secondary metabolites 3,4,5,6,7,8,9,10,11,12 previously isolated by our group from J. brevifolia were evaluated and some SAR has been established. The 18-hydroxydehydroabietane displayed great antiproliferative activity against cancer cell lines tested, namely HeLa, A-549 and MCF-7. Compound also presented a significant bactericidal effect against Bacillus cereus at different concentrations tested.
- Três minutos em duas horas ou a demência do DesassossegoPublication . Silva, Leonor Sampaio da
- Azorean savings banks and the 1929 economic crisisPublication . Lopes, Fernando Rosa Rodrigues; Dias, Fátima SequeiraWhat sets the Azorean banking system apart in the Portuguese context is the concentration of Caixas Económicas or Saving Banks accounting for half of these financial institutions in Portugal. These saving banks were promoted and had as shareholders mainly small and medium local traders and landlords with export business. This contrasts with the overwhelming concentration of big traders and traditional landlords as agents of international and national banks. These small institutions were the only network covering most of the islands and preceded the expansion of a national bank network of agencies created mostly after the Second World War. This article examines the effects of the 1929 crisis on the Azorean banking system which was generalized, and had deep and long-lasting effects, using unpublished data taken from the archive of Banco de Portugal. It is a case of contagion, typical of a banking crisis, affecting the credibility and confidence of all the institutions and leading to an interruption of payments for a period of over two years. Bankruptcies are limited to Caixa Bancária Raposo do Amaral and Caixa Económica Socorros Mútuos but the restructuring spreads over a ten year period. The contraction of monetary circulation caused by the banking crisis and the elimination of escudo insulano are also major contributing factors to the long and deep economic crisis that spread from 1929 to 1945. The banking crisis together with the protectionism of European markets and Portuguese colonial policies lead to the reorientation of the agro-export model to mainland Portuguese markets.
- Behavioural responses of Risso’s dolphin, Grampus griseus, to remote biopsy samplingPublication . Hartman, Karin L.; Wittich, Anja; Neves, Dalia; Azevedo, José M. N.Biopsy sampling from free-ranging cetaceans is a widespread method used in various biological studies. Since this is an intrusive research technique, it’s important to determine its impact. We examined the short-term behavioural reactions of Risso’s dolphins, Grampus griseus (2.6-4m in length), off Pico Island, to remote biopsy sampling. Biopsies were conducted over a consecutive two year period using a crossbow with Finn Larsen bolts and tips. Sampling followed a number of precautionary rules, including taking samples only in calm seas, when animals were travelling; no more than 1-4 shots per group; and females with nursing calves were not exposed to sampling. Behavioural responses were analysed by visual observation using two scales of behavioural reactions: i) the reaction of the targeted individual, and ii) the reaction of the focal group to which the targeted individual belonged. We defined five categories of intensity of behavioural response (none, low, medium, high, very high) and five types of display response (quick dive, QD; diving & leaving, D&L; jumping, J; tail slapping, TS; and speeding away at surface, SS). A total of 189 shots were made (115 hits, 74 miss) during 61 survey days. Tissue was obtained in 83% of the hits. No significant differences were found between hits and misses in behavioural responses or types of display (Kruskal Wallis test). In 9% of the cases there was no visible reaction, while most (48%) behavioural responses were of low intensity. The frequencies of the display responses differed significantly from each other (chi-squared test). The types QD and D&L constituted 79% of the responses. Group reaction was observed during 1/5 of the shots, (main behaviour D&L-51%). Although biopsy sampling is an invasive method, our results indicate that if basic precaution rules are followed low intensity behavioural responses can be expected for half of the time.
- Habitats Directive species lists : urgent need of revisionPublication . Cardoso, Pedro1. The European Habitats Directive is the main legislative work regarding Europe’s nature conservation policy. It lists the protected habitats and species in the European Union. The species lists include 122 arthropods. 2. The current lists of arthropods (Annexes II and IV) present, possibly among other, five obvious biases: taxonomic, geographic, range, size and aesthetic biases. Species of selected taxa (Lepidoptera, Coleoptera, Odonata and Orthoptera), from Northern or Central Europe, relatively widespread, of a large body size and attractive are favoured over species of other taxa, from southern and Mediterranean Europe, endemic or relatively small or inconspicuous. Such biases are obstacles to the effective protection of the European fauna. 3. Two main strategies should be followed to avoid these problems and therefore increase the effectiveness of conservation policies: (i) the adoption of objective and transparent criteria for the listing of protected species, and (ii) implement regular updates and amendments to the lists based on such criteria.
- Taxonomic studies in the Schizymeniaceae (Nemastomatales, Rhodophyta): on the identity of Schizymenia sp. in the Azores and the generic placement of Nemastoma confusumPublication . Gabriel, Daniela; Schils, Tom; Parente, Manuela I.; Draisma, Stefano; Neto, Ana I.; Fredericq, SuzanneComparative rbcL sequence analysis indicates that the species going under the name Schizymenia dubyi in the Azores should be referred to as S. apoda. Sequences of Schizymenia specimens from China and Namibia were also identified as S. apoda, of which the type locality is the Cape Province in South Africa. Schizymenia dubyi, described from Atlantic France, is clearly a distinct species that we here report for Japan and Sicily in the Mediterranean Sea. Both Schizymenia species, along with an unreported species from Japan, are distinct from S. pacifica described from Washington, in the Pacific Coast of North America. Secondary pit connections were observed in gametophytes of S. apoda from the Azores, a previously unknown character for the Nemastomatales. Examination of type material of Nemastoma confusum indicates that this species, currently placed in the Nemastomataceae, should be transferred to the genus Platoma in the Schizymeniaceae. A morphological comparison between Platoma confusum (Kraft & John) comb. nov. with descriptions of P. cyclocolpum and P. chrysymenioides suggests that the three species are closely related.
- Determinants of spider species richness in coastal dunes along a gradient of mediterraneityPublication . Carvalho, José Carlos; Cardoso, Pedro; Crespo, Luís C.; Henriques, Sérgio; Carvalho, Rui; Gomes, Pedro1. The Iberian Peninsula is one of the most relevant areas in terms of species richness, rarity and endemism in the Mediterranean Basin. Using spiders as a model, we studied the relative importance of environmental and non-environmental spatial variation along a gradient of mediterraneity on the western coast of the Iberian Peninsula. 2. We performed a spatially explicit analysis to evaluate the contribution of pure environmental and pure spatial effects and their shared influence on spider species richness by variation partitioning and principal coordinates of neighbour matrices (PCNM). We dissect the spatial variation of species richness into additive scale-specific models through PCNM analysis and estimate the relative importance of environmental variables for each model. 3. Variation partitioning revealed that 72.8% of species richness variation could be explained by the environmental (climate and dune stability) and spatial variables. Most of this variation (51.3%) corresponds to the environmental spatially structured component. 4. The influence of environmental variables was scale-dependent. At the broadest scales, the latitudinal-climatic gradient was the dominant factor that influenced spider species richness variation. At the finest scale, stability of the dune system was the most important component. 5. In conclusion, spider species richness patterns were determined mostly by spatially structured environmental variation. More importantly, this study shows that different environmental factors act at multiple scales. Hence, our results reinforce the importance of the incorporation of both local and broad-scale factors when examining species richness patterns.
- Criação de empresas em Portugal e Espanha: análise comparativa com base nos dados do Banco MundialPublication . Sarmento, Elsa de Morais; Nunes, AlcinaDo Inquérito ao Empreendedorismo do Banco Mundial (WBGES 2008) resultou uma extensa base de dados de cerca de uma centena de países, baseada em dados dos registos notariais. Com base nesta fonte de informação, exploramse as trajectórias de evolução da criação de empresas entre 2000 e 2007 entre dois países geográfica e economicamente próximos, Portugal e Espanha, e destes países relativamente à União Europeia e à OCDE, bem como a outros países e fontes de informação. Análises anteriores, com base noutras fontes de informação, apontam para taxas de criação de empresas em Portugal superiores às de Espanha. Os dados do WBGES permitem validar essas conclusões. Porém, Portugal evidencia uma volatilidade superior no registo de empresas. Em 2001, o elevado acréscimo no registo de novas empresas representa um fenómeno isolado e específico para Portugal, não havendo paralelo nem nos países europeus da coesão, nem ao nível da média da União Europeia. O projecto Empresa na Hora não teve um impacto visível a nível do registo de empresas, considerando a evolução ao longo deste período. Por outro lado, Espanha detém uma densidade empresarial considerável, não só do total de empresas registadas, mas também do registo de novas empresas, apesar de Portugal apresentar taxas de crescimento médias superiores do registo de novas empresas, indiciando maiores taxas de sobrevivência empresarial que as existentes em Portugal. No entanto, de acordo com os dados dos registos de criação de empresas, apesar de Portugal e Espanha apresentarem densidades empresariais superiores à média da União Europeia e da OCDE, possuem taxas de registo de novas empresas relativamente mais baixas, o que leva a concluir por uma relativa menor dinâmica empresarial na criação de novas empresas. Finalmente, constata-se que as taxas de criação de empresas baseadas no WBGES 2008 são menos elevadas do que as obtidas quando se considera o universo de empresas economicamente activas. Este facto indica que análises comparativas de empreendedorismo não devem considerar isoladamente os dados oficiais de registo de empresas, devendo ser complementadas com outras fontes de informação, onde esteja representado o universo relevante de empresas que se encontrem efectivamente em actividade.
- A perspective on the symptoms and causes of the financial crisisPublication . Cabral, RicardoThis article identifies two paradoxes prior to the onset of the financial crisis: banking profits were at historically high levels despite the impending crisis; and though profits were high the profitability of financial intermediation was poor. Using a novel model of banking, it argues that large banks attained high profits through balance sheet expansion and growing mismatches between assets and liabilities. As a result, large banks’ financial leverage rose while their liquidity structure worsened, setting the conditions for a systemic banking crisis. Finally, this article argues that this conduct and performance was only possible due to misguided changes to the regulatory framework, specifically the Basel I Capital Accord and reductions in reserve requirements.
- Caracterização molecular de Listeria monocytogenes ser. 4b por Amplified Fragment Length Polymorphism (AFLP)Publication . Goulão, Maria Manuela Martins Francisco; Pintado, Cristina Maria Baptista Santos; Ferreira, Maria Adélia da Silva SantosO serotipo maioritariamente associado às estirpes de Listeria monocytogenes isoladas de queijos Portugueses pertence ao serotipo 4b, o qual está referido na literatura como o responsável pelo maior número de casos de listeriose humana. Tendo em conta a importância de que se revestem estas estirpes, a sua caracterização usando métodos mais discriminatórios que a serotipagem é de crucial importância. Assim, o presente estudo teve por finalidade a caracterização molecular de estirpes de L. monocytogenes ser. 4b, isoladas de queijos de diferentes zonas do país, e uma primeira avaliação da distribuição geográfica dos tipos moleculares encontrados. Foi usado o método Amplified Fragment Length Polymorphism (AFLP) com base no protocolo que se encontra em funcionamento no Health Protection Agency Department of Gastrointestinal Infections / Centre for Infections, em Londres. Para a análise da similaridade entre estirpes recorreu-se ao programa Bionumerics. O poder discriminatório do método AFLP foi calculado através do índice de Simpson. Das 47 estirpes de L. monocytogenes ser. 4b tipadas neste trabalho resultaram 6 perfis diferentes com um número de bandas compreendido entre 5 a 7 no intervalo entre 500 bp e 1500 bp. Todos os perfis AFLP apresentaram uma banda comum de aproximadamente 850 bp. O poder discriminatório do método AFLP foi avaliado em 0,70. Pela análise do dendrograma observou-se a existência de 6 clusters para uma percentagem de similaridade de 98%, os quais foram agrupados de acordo com o tipo AFLP previamente atribuído. A relação de similaridade mais afastada encontrada entre os 47 isolados foi de 67%. Considerando a totalidade dos isolados provenientes da região da Serra da Estrela, foi possível identificar 5 tipos AFLP, quatro dos quais identificados apenas naquela zona e um quinto tipo AFLP com uma distribuição geográfica alargada (Serra da Estrela, Serpa e São Jorge), o que contraria a sua utilização como marcador geográfico. Comparando estes 47 perfis com os obtidos anteriormente pelo mesmo método usando isolados provenientes das zonas produtoras de queijo de Castelo Branco e Tolosa (n=61), concluise que os tipos AFLP obtidos são diferentes, não havendo tipos AFLP comuns entre as zonas de Tolosa, Castelo Branco e Serra da Estrela, indicando uma associação entre um determinado tipo AFLP de L. monocytogenes ser. 4b e cada uma destas regiões.
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