Browsing by Issue Date, starting with "2001"
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- DNA variation at the rp49 gene region in Drosophila madeirensis and D. subobscura from Madeira: inferences about the origin of an insular endemic speciesPublication . Khadem, M.; Rozas, J.; Segarra, C.; Aguade, M.An 1.6-kb fragment spanning the rp49 gene was sequenced in 16 lines of Drosophila subobscura from Madeira and in 22 lines of the endemic species D. madeirensis. Nucleotide diversity in D. subobscura from Madeira (p 0.0081) was similar to that in lines from Spain carrying the O3+4 chromosomal arrangement (p 0.0080). No signi®cant genetic differentiation was detected between insular and continental O3+4 lines of D. subobscura. These results are compatible both with a rather recent and massive colonization, and with multiple colonization events from the continent. Nucleotide diversity in D. madeirensis (p 0.0076) was similar to that in D. subobscura, which deviates from the expectation, under strict neutrality, of a lower level of variation in an insular species with a small population size. The observed numbers of shared polymorphisms and of ®xed differences between D. madeirensis and D. subobscura are compatible with the isolation model of speciation, where shared polymorphisms are due to common ancestry.
- Object modeling for user-centered development and user interface design: the wisdom approachPublication . Nunes, Nuno Jardim
- Roteiro [da] Freguesia de São Jorge: Ilha da MadeiraPublication . Sousa, Élvio; Spínola, Hélder; Perestrelo, Idalina
- Roteiro turístico-cultural [da] Freguesia da Camacha: Ilha da MadeiraPublication . Spínola, Hélder; Sousa, Élvio Duarte Martins; Perestrelo, Idalina
- Como resolver problemas de matemáticaPublication . Gonçalves, Ida Maria Faria de Lira
- Lack of congruence between morphometric evolution and genetic differentiation suggests a recent dispersal and local habitat adaptation of the Madeiran lizard Lacerta dugesiiPublication . Brehm, António; Khadem, Mahnaz; Jesus, José; Andrade, Paula; Vicente, LuísGenetic differentiation among nine populations of the endemic lizard Lacerta dugesii Milne-Edwards 1829 (Lacertidae) from four groups of islands constituting the Archipelago of Madeira, was investigated by protein electrophoresis at 23 enzyme loci. Among twenty polymorphic loci, the total genetic diversity was due primarily to intra-population variation. The allele and genotypic frequencies among populations showed some heterogeneity, allowing the species to present a structuring pattern compatible with their geographical clustering. Some evidence suggests that selection acting on some loci in different ecological conditions may be responsible for the clustering of the populations studied. There was no apparent isolation effect expected under an "island" model of population divergence, and no correlation was found between genetic and geographic distances among populations. Morphological variation of the proposed three L. dugesii subspecies is not congruent with the allozyme analysis. This most probably suggests a rapid colonization of the islands followed by a strong effect of selection operating over the morphological characters used to define the subspecies.
- Etnografia da educaçãoPublication . Fino, Carlos Nogueira
- Properties and processing of cork powder filled cellulose derivatives compositesPublication . Godinho, Maria Helena; Martins, Assis Farinha; Belgacem, Mohamed Naceur; Gil, Luís; Cordeiro, NereidaThis paper deals with the use of cork powder, a by‐product from cork industry, as a filler to reinforce hydroxypropyl cellulose (HPC) matrix. Several films were prepared using HPC, as a matrix, filled with different amounts of cork powder (average diameter < 50 μm) (0.0; 0.5; 1.0 and 10.0% w/w) and in the presence or not of 1,4‐diisocyanatobutane (BDI) (7.0% w/w). Before the elaboration of these films, the surface properties of cork powder as well as that of suberin (main component of cork) were determined by Inverse Gas Chromatography (IGC). The tensile properties of the solid films obtained were studied and, as expected, for the films with BDI but without cork powder, the Young's modulus and the tensile strength increased, while the elongation decreased. However with the filled films it seemed that the Young's modulus decreased and the elongation increased. The Scanning Electron Microscopy showed that the fractured plane of samples with cross‐linking agent and cork powder displayed some nucleation points (0.3 μm) which indicates a strongly bonded interface and which could be considered as a responsible for the high mechanical properties observed.
- A provisional checklist of the Rove Beetles of Madeira Island (Coleoptera, Staphylinidae)Publication . Boieiro, Mário; Serrano, Artur R. M.; Menezes, Dília; Pombo, Dora; Capela, Rúben
- Phylogeography of the human mitochondrial haplogroup L3e: a snapshot of African prehistory and Atlantic slave tradePublication . Bandelt, H.-J.; Alves-Silva, J.; Guimarães, P. E. M.; Santos, M. S.; Brehm, A.; Pereira, L.; Coppa, A.; Larruga, J. M.; Rengo, C.; Scozzari, R.; Torroni, A.; Prata, M. J.; Amorim, A.; Prado, V. F.; Pena, S. D. J.The mtDNA haplogroup L3e, which is identified by the restriction site 2349 MboI within the Afro-Eurasian superhaplogroup L3 (®3592 HpaI), is omnipresent in Africa but virtually absent in Eurasia (except for neighbouring areas with limited genetic exchange). L3e was hitherto poorly characterised in terms of HVS-I motifs, as the ancestral HVS-I type of L3e cannot be distinguished from the putative HVS-I ancestor of the entire L3 (differing from the CRS by a transition at np 16223). An MboI screening at np 2349 of a large number of Brazilian and Caribbean mtDNAs (encompassing numerous mtDNAs of African ancestry), now reveals that L3e is subdivided into four principal clades, each characterised by a single mutation in HVS-I, with additional support coming from HVS-II and partial RFLP analysis. The apparently oldest of these clades (transition at np 16327) occurs mainly in central Africa and was probably carried to southern Africa with the Bantu expansion(s). The most frequent clade (transition at np 16320) testifies to a pronounced expansion event in the mid-Holocene and seems to be prominent in many Bantu groups from all of Africa. In contrast, one clade (transition at np 16264) is essentially restricted to Atlantic western Africa (including Cabo Verde). We propose a tentative L3e phylogeny that is based on 197 HVS-I sequences. We conclude that haplogroup L3e originated in central or eastern Africa about 46,000 (³14,000) years ago, and was a hitchhiker of much later dispersal and local expansion events, with the rise of food production and iron smelting. Enforced migration of African slaves to the Americas translocated L3e mitochondria, the descendants of which in Brazil and the Caribbean still reflect their different regional African ancestries.