Browsing by Issue Date, starting with "2013-12"
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- The foundation of literary periodicals in the third quarter of the nineteenth century: literature promotion or a political and educational agenda?Publication . Baleiro, Rita; Ribeiro, F.P.The article presents 8 first-editorials published in Portuguese literary periodicals (1855-1865). The research explores the aims of the publications established during a Portuguese literary controversy - Questao Coimbra. By applying detailed text analysis, it addresses the following: a) editorial orientations; b) relationship fostered with the audience(s); c) target-audience(s)? Analysis points to strong educational concerns, mirroring the socio-historic context that placed great emphasis on the promotion of public education, when over 70% of the population was illiterate and in some cases to tightening the links with Brazil.
- Ambientes colaborativos virtuais: potencial das redes sociais. O caso das empresas do AlgarvePublication . Belo, Ana; Castela, Guilherme; Fernandes, Silvia BritoO objetivo do presente artigo é analisar o potencial das redes sociais no desempenho das pequenas e médias empresas da região do Algarve, tendo sido efectuado um questionário para o efeito. O estudo empírico realizado revela que os dados recolhidos (de 70 empresas) possuem boas qualidades psico-métricas. Procedeu-se a uma análise categórica de componentes principais, a qual identificou duas principais tipologias de objectivos nas redes sociais: redes sociais para interacção produto-cliente e pesquisa ou conhecimento; e redes sociais com potencial para o marketing. Uma análise suplementar - análise hierárquica de clusters (com recurso ao método de agrupamento de Ward) - identificou três padrões de empresas consoante o seu grau de envolvimento em redes sociais: cluster Social Tec Grau 1; cluster Social Tec Grau 2 e cluster Social Tec Grau 3. Estas análises permitem validar uma metodologia sustentável para este tipo de avaliação.
- Peroxides with antiplasmodial activity inhibit proliferation of Perkinsus olseni, the causative agent of Perkinsosis in bivalvesPublication . Araujo, Nuna C. P.; Afonso, Ricardo; Bringela, A.; Cancela, Leonor; Cristiano, Maria Lurdes Santos; Leite, RicardoPerkinsus olseni, the causative agent of Perkinsosis, can drastically affect the survival of target marine mollusks, with dramatic economic consequences for aquaculture. P. olseni is a member of the Alveolata group, which also comprises parasites that are highly relevant for medical and veterinary sciences such as Plasmodium falciparum and Toxoplasma. P. olseni shares several unique metabolic pathways with those pathological parasites but is not toxic to humans. In this work, six antimalarially active peroxides, derived from the natural product artemisinin or synthetic trioxolanes, were synthesized and tested on P. olseni proliferation and survival. All peroxides tested revealed an inhibitory effect on P. olseni proliferation atmicromolar concentrations. The relevance of the peroxide functionality on toxicity and the effect of Fe(II)-intracellular concentration on activity were also evaluated. Results demonstrated that the peroxide functionality is the toxofore and intracellular iron concentration also proved to be a crucial co-factor on the activation of peroxides in P. olseni. These data points to a mechanismof bioactivation in P. olseni sharing similaritieswith the one proposed in P. falciparumparasites. Preliminary studies on bioaccumulation were conducted using fluorescent-labeled peroxides. Results show that synthetic trioxolanes tend to accumulate on a vacuolewhile the labeled artemisinin accumulates in the cytoplasm. Preliminary experiments on differential genes expression associated to Fe(II) transport protein (Nramp) and calcium transport protein (ATP6/SERCA) were also conducted by qPCR. Results point to a fourfold increase in expression of both genes upon exposure to trioxolanes and approximately twofold upon exposure to artemisinin derivatives. Data obtained in this investigation is relevant for better understanding of the biology of Perkinsus andmay also be important in the development of new strategies for Perkinsosis prevention and control.
- The Interview: methodological framework in the study of 'tourism and economics: the Faro Airport (1946-73)'Publication . Pereira, Renato Nuno; Leite, Joaquim da Costa; Silva, João AlbinoThis methodological paper defines how to interview people regarding the decision-making process, construction and operation of Faro Airport and its role in the Portuguese tourism policy for the Algarve between 1946 and 1973. The interviewee’s age makes these interviews urgent and unique. We will hear retired workers and people who held head positions at the airport or in other relevant public or private organizations. The interviews will allow the access to data otherwise not attainable or not sufficiently evident in other sources, such as documents. The interview consists of hearing the stories of the people, as a narrative, being the interview a semi-structured, guided and unstructured mix. The use of photographs during the interview will help respondents recall events that occurred decades ago. The interviewee will be selected by snowball sampling technique. Content analysis is the method to obtain data from the transcripts of the interviews, in order to construct a coherent narrative and with the contribution of all the interviews and interviewee. As field instruments, we will use an informed consent form, photographs and the confidentiality form after the interview, which responds to the ethical requirement for confidentiality, consequences of the interview and the role of the researcher.
- Contribution for the validation of the portuguese version of EQ-5DPublication . Ferreira, Pedro Lopes; Ferreira, Lara Noronha; Pereira, Luis NobreIntroduction: The EQ-5D allows the achievement of two essential components of any measure of health-related quality of life to be used in cost-utility economic evaluations: (i) a profile describing the health status in terms of domains or dimensions; and (ii) a numeric value associated with the health status described. Aim: The Portuguese version of the EQ-5D questionnaire was completed in 1998, based on guidelines set by the EuroQol Group, including translation and back translation procedures. Despite its wide use in Portugal, until now it had not yet been published studies that initially led to the Portuguese version and the guarantee of acceptability, reliability and validity. The purpose of this article is to document these first values relating to the Portuguese version of the EQ-5D. Material and Methods: We used three different samples: a first one with 1,500 individuals representative of the Portuguese population; a second with 140 individuals just intended for the reliability test; and a third sample with 643 individual patients with cataracts, asthma, chronic obstructive pulmonary disease, or rheumatoid arthritis. Results: The acceptability was assessed by the number of missing responses. It was also found a marked ceiling effect, with a large part of the sample not reporting any problems in the dimensions of the EQ-5D. Discussion: The construct validity was tested by examining the degree to which low values of EQ-5D were positively associated with increasing age, being female, and the sick, as well as the values of dimensions of the SF-36v2 scale. Convergent validity was based on correlations between EQ-5D values and other specific measures. The EQ-5D showed moderate to high correlations with other disease-specific measures of health status and health related quality of life. Conclusion: We can state that the Portuguese version of the EQ-5D has a good accessibility, reliability and validity in measuring health.
- Mother knows best: occurrence and associations of resighted humpback whales suggest maternally derived fidelity to a southern hemisphere coastal feeding groundPublication . Barendse, Jaco; Best, Peter B.; Carvalho, Inês; Pomilla, CristinaSite fidelity is common among migratory cetaceans, including humpback whales (Megaptera novaeangliae). In the Northern Hemisphere it has been found that fidelity to humpback whale feeding grounds is transferred maternally but this has never been shown for the species in the Southern Hemisphere. We examined this in a unique feeding area off west South Africa using resighting data of 68 individually identified humpback whales by means of photographic (tail flukes and dorsal fins) and/or molecular methods (microsatellite genotyping) over an 18 year span. We found short-term association patterns and recurrent visits typical of other feeding grounds. Males and females had different seasonality of attendance. Significant female-dominated presence corresponded to timing of an expected influx of females on their southward migration from the breeding ground: firstly non-nursing (possibly pregnant) females in mid-spring, and mothers and calves in mid-to late summer. The potential benefit of this mid-latitude feeding area for females is illustrated by a record of a cow with known age of at least 23 years that produced calves in three consecutive years, each of which survived to at least six months of age: the first record of successful post-partum ovulation for this species in the Southern Hemisphere. We recorded association of a weaned calf with its mother, and a recurring association between a non-lactating female and male over more than two years. Moreover, three animals first identified as calves returned to the same area in subsequent years, sometimes on the same day as their mothers. This, together with numerous Parent-Offspring relations detected genetically among and between resighted and non-resighted whales is strongly suggestive of maternally derived site fidelity at a small spatial scale by a small sub-population of humpback whales.
- Elvis Presley y la tradicion del cine musical de HollywoodPublication . Carrega, JorgeDepreciadas por la crítica cinematográfica, las películas protagonizadas por Elvis Presley son ejemplos relevantes de uno de los principales subgéneros del cine musical de Hollywood, la comedia musical protagonizada por intérpretes de la canción popular tornados actores como Bing Crosby, Frank Sinatra, Carmen Miranda, Doris Day y Dean Martin. Pioneros en la introducción de una nueva estética musical en el cine de Hollywood, estas películas permiten una mejor comprensión de las transformaciones sociales y culturales producidas en los decenios de 1950 y 1960 y su impacto en el sistema de los estudios y en particular en el género musical.
- Development of an in vitro cell system from zebrafish suitable to study bone cell differentiation and extracellular matrix mineralizationPublication . Vijayakumar, Parameswaran; Laizé, Vincent; Cardeira Da Silva, João; Trindade, Marlene; Cancela, M. LeonorMechanisms of bone formation and skeletal development have been successfully investigated in zebrafish using a variety of in vivo approaches, but in vitro studies have been hindered due to a lack of homologous cell lines capable of producing an extracellular matrix (ECM) suitable for mineral deposition. Here we describe the development and characterization of a new cell line termed ZFB1, derived from zebrafish calcified tissues. ZFB1 cells have an epithelium-like phenotype, grow at 28 degrees C in a regular L-15 medium supplemented with 15% of fetal bovine serum, and are maintained and manipulated using standard methods (e.g., trypsinization, cryopreservation, and transfection). They can therefore be propagated and maintained easily in most cell culture facilities. ZFB1 cells show aneuploidy with 2n=78 chromosomes, indicative of cell transformation. Furthermore, because DNA can be efficiently delivered into their intracellular space by nucleofection, ZFB1 cells are suitable for gene targeting approaches and for assessing gene promoter activity. ZFB1 cells can also differentiate toward osteoblast or chondroblast lineages, as demonstrated by expression of osteoblast- and chondrocyte-specific markers, they exhibit an alkaline phosphatase activity, a marker of bone formation in vivo, and they can mineralize their ECM. Therefore, they represent a valuable zebrafish-derived in vitro system for investigating bone cell differentiation and extracellular matrix mineralization.
- Pericentromeric location of the telomeric DNA sequences on the European grayling chromosomesPublication . Ocalewicz, K.; Furgala-Selezniow, G.; Szmyt, M.; Lisboa, R.; Kucinski, M.; Lejk, A. M.; Jankun, MalgorzataThe chromosomal characteristics, locations and variations of the C-band positive heterochromatin and telomeric DNA sequences were studied in the European grayling karyotype (Thymallus thymallus, Salmonidae) using conventional C-banding, endonucleases digestion banding, silver nitrate (AgNO3), chromomycin A(3) and 4',6-diamidino-2-phenylindole staining techniques as well as fluorescence in situ hybridization (FISH) and primed in situ labelling. Original data on the chromosomal distribution of segments resistant to AluI restriction endonuclease and identification of the C-banded heterochromatin presented here have been used to characterize the grayling karyotype polymorphism. Structural and length polymorphism of the chromosome 21 showing a conspicuous heterochromatin block adjacent to the centromere seems to be the result of the deletion and inversion. Two pairs of nuclear organizer regions (NOR)-bearing chromosomes were found to be polymorphic in size and displaying several distinct forms. FISH with telomeric peptide nucleic acid probe enabled recognition of the conservative telomeric DNA sequences. The karyotype of the thymallid fish is thought to experienced numerous pericentric inversions and internal telomeric sites (ITSs) observed at the pericentromeric regions of the six European grayling metacentric chromosomes are likely relics of the these rearrangements. None of the ITS sites matched either chromosome 21 or NOR bearing chromosomes.
- Genetic evidence for polygynandry in the black-striped pipefish syngnathus abaster: a microsatellite-based parentage analysisPublication . Huebner, Kerstin; Gonzalez-Wanguemert, Mercedes; Diekmann, O. E.; Serrão, EsterSexual selection theory predicts that, in organisms with reversed sex roles, more polyandrous species exhibit higher levels of sexual dimorphism. In the family Syngnathidae (pipefish, seahorses, and seadragons), males provide all parental care by carrying developing embryos on their ventral surfaces, and females develop secondary sex characters. Syngnathids exhibit a variety of genetic mating patterns, making them an ideal group to test predictions of sexual selection theory. Here, we describe the mating system of the black-striped pipefish Syngnathus abaster, using 4 highly variable microsatellites to analyze parentage of 102 embryos. Results revealed that 1) both sexes mate multiple times over the course of a pregnancy (polygynandrous mating system), 2) eggs are spatially segregated by maternity within each brood pouch, and 3) larger females have higher mating success (Kolmogorov–Smirnov test; P < 0.05). Together with similar studies of other syngnathid species, our results support the hypothesis that the mating system is related to the intensity of sexual dimorphism.
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