Browsing by Issue Date, starting with "1997"
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- Population genetic structure and colonization sequence of Drosophila subobscura in the Canaries and Madeira Atlantic islands as inferred by autosomal, sex-linked and mtDNA traitsPublication . Pinto, F. M.; Brehm, A.; Hernández, M.; Larruga, J. M.; González, A. M.; Cabrera, V. M.The genetic structure In Atlantic Islands and continental populations of Drosophila subobscura has been studied using autosomal and sex-linked allozymes and ml tochondrial DNA (mtDNA) haplotypes. From the data it Is deduced that whereas the Canary Islands have long been isolated, the neighboring island of Madeira has been subjected to continuous migration from the mainland. In addition, sex-linked allo zymes and mtDNA data show a large divergence between the geologically younger western Islands of the Canarian Archipelago and the older central ones, finding strong founder effects In the former. Divergence rates of sex-linked and mltochon drlal genes relative to autosomlc loci several times higher than expected under neutrality have been explained by differential migration between sexes. The Ca narian Archipelago colonization fits in well with a stepping-stone model of a direc tional east-west migration that parallels the geological origin of these Islands.
- António Sérgio e o self-governmentPublication . Fino, Carlos Nogueira
- Ressonâncias das makáron nésoi / fortunatorum insulae da Antiguidade Clássica em textos sobre a Ilha da MadeiraPublication . Pinheiro, Joaquim J. Sanches
- Surface properties of suberinPublication . Cordeiro, Nereida; Aurenty, Patrice; Belgacem, Mohamed Naceur; Gandini, Alessandro; Neto, Carlos PascoalThe surface energy of suberin was determined by four different methods, namely, (i) contact angle measurements, (ii) Wilhelmy plate measurements, (iii) maximum bubble pressure, and (iv) inverse gas chromatography (IGC). The first three methods gave a gammasub value in the range 40-50 mN m-1 at room temperature. The major component of this value reflects the dispersive contribution. The IGC measurements showed a higher dispersive term, which is common with this method of characterization. The surface acid (A)/base (B) properties were also evaluated, and the results indicated that suberin has an acidic character.
- Studies of the species barrier between Drosophila subobscura and D. madeirensis IV. A genetic dissection of the X chromosome for speciation genesPublication . Khadem, M.; Krimbas, C. B.The genetics of four traits contributing to the isolation mechanism between the two closely related species of Drosophilu belonging to the obscuru group, D. subobscura and D. madeirensis, have been investigated, especially regarding the influence exerted by the X chromosome. This chromosome has been roughly dissected genetically by the use of four markers. It was found that factors affecting viability of backcross males are spread from the centromeric end of the chromo some up the region marked by Bx. Three sections were responsible for male sterility/fertility. The abnormal head shape of the backcross males was affected by factor(s) on the madeirensis and the subobscura sex chromosome located at the region of MAD1 inversion. Finally, an abnormal trait in these males (presence of extra sex combs) was found to be controlled by four sections, two on the madeirrnsis X chromosome and two on the subobscuru one.
- Literatura de viagens na MadeiraPublication . Carita, Rui
- A configuração da ilha na obra poética de Rui CinattiPublication . Nascimento, Maria Teresa
- Investigação em educação: novos desafiosPublication . Sousa, Jesus Maria
- Helminth parasites of Madeiran rockpool fishes, with a redescription of Schikhobalotrema longivesiculatum Orecchia & Paggi, 1975 (Digenea: Haplosplanchnidae), and some comments on their zoogeographical relationshipsPublication . Gibson, David I.; Costa, GraçaSeven species of Madeiran rockpool fishes were examined for their helminth parasites. Only two of these harboured helminth parasites. The most frequently encountered parasite was the digenean Schikhobalotrema longivesiculatum Orecchia & Paggi, 1975 from Parablennius parvicornis; this species is redescribed and discussed. The paucity of the parasite fauna of Madeiran rockpool fishes and the zoogeographical relationships of the digenean fauna of Madeiran marine fishes are commented upon.