Browsing by Issue Date, starting with "2002"
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- As dinâmicas do global e do particular: o dilema do currículoPublication . Sousa, Jesus Maria
- Jatrophane and lathyrane diterpenoids from Euphorbia hyberna LPublication . Ferreira, Ana Margarida V. D.; Carvalho, Luı́s H. M.; Carvalho, Maria João M.; Sequeira, Miguel M.; Silva, Artur M. S.A new diterpene tetraester, from the jatrophane family, and two new diterpene triesters, with a lathyrane skeleton, have been isolated from the chloroform extract of the roots of Euphorbia hyberna L. The structures of these compounds have been established by spectroscopic methods, including 2D NMR experiments.
- A economia da Madeira (1850-1914)Publication . Câmara, Benedita
- The organosolv fractionation of cork componentsPublication . Cordeiro, Nereid; Neto, Carlos Pascoal; Rocha, Joao; Belgacem, Mohamed N.; Gandini, AlessandroExtractive-free cork from Quercus suber L. was submitted to organosolv fractionation and the effects of different process variables, such as ethanol/water ratio, temperature, time and the presence of acidic or alkaline catalysts, were studied. The variation of the relative proportions of extracted components, as a function of the processing conditions, could thus be established. Whereas the addition of 0.1 M acetic acid only increased the yield of extracted materials from about 15 to 23%, the use of sodium hydroxide, at the same concentration, produced a jump to 76%. In the case of the alkaline organosolv fractiona tion, an increase in process temperature, time and catalyst concentration led to an increase in the extraction yield, although in some cases this increase did not follow a sustained trend, as in the case of reaction time. Increasing the ethanol/water ratio led to a higher selectivity in favour of suberin extraction. Residual cork from different organosolv processes was characterised by FTIR and 13C solid-state NMR. The latter technique provided some valuable information about both process selectivity and cork morphology, particularly with respect to the positioning of suberin macromolecules in the cell wall.
- Cereais, tubérculos e gadoPublication . Câmara, Benedita
- Genetic markers in the study of Anisakis typica (Diesing, 1860): larval identification and genetic relationships with other species of Anisakis Dujardin, 1845 (Nematoda: Anisakidae)Publication . Mattiucci, S.; Paggi, L.; Nascetti, G.; Portes Santos, C.; Costa, G.; Di Beneditto, A.P.; Ramos, R.; Argyrou, M.; Cianchi, R.; Bullini, L.Genetic variation at 21 gene-enzyme systems was studied in a sample of an adult population of Anisakis typica (Diesing, 1860) recovered in the dolphin Sotalia fluviatilis from the Atlantic coast of Brazil. The characteristic alleles, detected in this population, made it possible to identify as A. typica, Anisakis larvae with a Type I morphol ogy (sensu Berland, 1961) from various fishes: Thunnus thynnus and Auxis thazard from Brazil waters, Trachurus picturatus and Scomber japonicus from Madeiran waters, Scomberomorus commerson, Euthynnus affinis, Sarda orientalis and Coryphaena hippurus from the Somali coast of the Indian Ocean, and Merluccius merluccius from the Eastern Mediterranean. Characteristic allozymes are given for the identification, at any life-stage and in both sexes, of A. typica and the other Anisakis species so far studied genetically. The distribution of A. typica in warmer temperate and tropical waters is confirmed; the definitive hosts so far identified for this species belong to delphinids, phocoenids and pontoporids. The present findings represent the first established records of intermediate/paratenic hosts of A. typica and extend its range to Somali waters of the Indian Ocean and to the Eastern Mediterranean Sea. A remarkable genetic homogeneity was observed in larval and adult samples of A. typica despite their different geographical origin; interpopulation genetic distances were low, ranging from DNei = 0.004 (Eastern Mediterranean versus Somali) to DNei = 0.010 (Brazilian versus Somali). Accordingly, indirect estimates of gene flow gave a rather high average value of Nm = 6.00. Genetic divergence of A. typica was, on average, DNei = 1.12 from the members of the A. simplex complex (A. simplex s.s, A. pegreffii, A. simplex C) and DNei = 1.41 from A. ziphidarum, which all share Type I larvae; higher values were found from both A. physeteris (DNei = 2.77) and A. brevispiculata (DNei = 2.52), which have Type II larvae (sensu Berland, 1961). Genetic relationships among these species are shown using multidimensional scaling ordination (MDS). The genus Anisakis appears to be phylogenetically heterogeneous and includes two distinct groups of species, which are morphologically and genetically differentiated.
- Distribution of HLA alleles in Portugal and Cabo Verde. Relationships with the slave trade routePublication . Spínola, Hélder; Brehm, A.; Williams, F.; Jesus, J.; Middleton, D.HLA-A,-B, and -DR frequencies were analysed in populations from Portugal and the Madeira and Cabo Verde Archipelagos, aiming to characterize their genetic composition. Portuguese settlers colonized both Archipelagos in the 15th and 16th centuries. Madeira received many sub-Saharan slaves to work in the sugar plantations, and Cabo Verde served as a pivotal market in the Atlantic slave trade and was populated by individuals coming from the Senegambia region of the West African coast. The population of Madeira shows the highest genetic diversity and the presence of alleles and haplotypes usually linked to sub-Saharan populations, the haplotypes accounting for 3±5% of the total. Cabo Verde presents typical markers acknowledged to be of European or IberoMediterranean origin, thus revealing the admixture of European settlers with Sub-Saharan slaves. Altogether the number of European haplotypes reaches 15% of the total. The Portuguese population shows a perceivable and significant heterogeneity both in allele and haplotype frequencies, unveiling a differential input of peoples from different origins. A PCA of the populations studied, plus other relevant ones, clearly shows gene heterogeneity in mainland Portugal as well as the differences and relationships between these populations and Madeira and Cabo Verde.
- Portugal: manifest for the republic education or teacher education under scrutinyPublication . Sousa, Jesus Maria; Fino, Carlos NogueiraStarting from the analysis of a Manifest placed in the World Wide Web in order to gather signatures, the paper discusses the arousal of a wide spread movement of scepticism in the so called Portuguese “civil socie ty” against the overall result of almost forty years of uninterrupted educational reform that has taken place in Portugal since the late sixties and has lead to an increasing percentage of illiteracy and innumeracy. That Manifest is presented as part of a broader movement, deeply rooted in the Portuguese society, and silent so far, which is becoming stronger and has now strength enough to be part of the political agenda. It is also our concern to unveil an emerging trend of blaming sciences of education and badly trained teachers as responsible for the poor outcome of our schooling system.
- A cana sacarina e os seus derivados (1850-1914)Publication . Câmara, Benedita
- Non-conventional reactive dye systems for attaching chromophores to wool, protein and polyamide substratesPublication . Moura, J. C. V. P.; Cordeiro, N.Reactive dyes, which form a covalent bond to the substrate onto which they are applied, have been used in textile applications for many years, and various reactive systems have been researched and commercialised. Reactive dyes also find use in biochemical and biotechnology areas, in particular as biolabels and tracers. This review examines reactive textile dye systems which have not achieved commercial acceptance, and also considers reactive systems that have been proposed solely for biochemical application to proteins.