Browsing by Issue Date, starting with "1998"
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- Suberin-based polyurethanes: synthesis, characterization and kinetics of their formationPublication . Cordeiro, N.; Belgacem, M. N.; Gandini, A.; Pascoal Neto, C.
- A Madeira e o proteccionismo sacarino (1895-1918)Publication . Câmara, Benedita
- As metáforas das Ilhas em Dante, Borges e SophiaPublication . Martins, Celina Rodrigues
- Fraccionamento da cortiça e caracterização dos seus componentes: estudo de possibilidades de valorização suberinaPublication . Cordeiro, Nereida Maria Abano
- Complements in modular and semimodular latticesPublication . Bordalo, G. H.; Rodrigues, E.We study the relations between the complements of a and b when a is covered by b on finite upper-semimodular lattices and when a < b on modular lattices. We give some results that generalize the well known properties of complements in distibutive lattices. From there, we derive a property of semisimple R-modules.
- Modes de consommation et manières de table dans les Alpes du sudPublication . Escallier, Christine
- Products of the permanganate oxidation of Cork, desuberized Cork, suberin and lignin from Quercus suber L.Publication . Lopes, M.; Neto, C. Pascoal; Evtuguin, D.; Silvestre, A. J. D.; Gil, A.; Cordeiro, N.; Gandini, A.
- Cork suberin as a new source of chemicals.: 1. isolation and chemical characterization of its compositionPublication . Cordeiro, N.; Belgacem, M.N.; Silvestre, A.J.D.; Pascoal Neto, C.; Gandini, A.Extractive-free cork from Quercus suber L. was submitted to a solvolysis treatment with methanolic NaOH which yielded 37% (o.d. cork) of suberin. This mixture of compounds was thoroughly characterized by FTIR, 1 H- and 13C-NMR, gas chromatogra phy coupled with mass spectrometric (GC–MS) analysis, vapour pressure osmometry (VPO), mass spectrography (MS) and gel permeation chromatography (GPC). After derivatization, the main components of the volatile fraction, representing less than half of the total, were found to be v-hydroxymonocarboxylates, a,v-dicarboxylates, simple alkanoates and 1-alkanols, all with chain lengths ranging from C16 to C24. A second fraction, with an average molecular weight about three times higher, was detected by VPO, MS and GPC. The presence of this important fraction in cork suberin had not been recognized in earlier studies. Both fractions constitute interesting precursors for the elaboration of new materials.
- Studies in non-Gaussian analysisPublication . Silva, José Luís daThis thesis presents general methods in non-Gaussian analysis in infinite dimensional spaces. As main applications we study Poisson and compound Poisson spaces. Given a probability measure μ on a co-nuclear space, we develop an abstract theory based on the generalized Appell systems which are bi-orthogonal. We study its properties as well as the generated Gelfand triples. As an example we consider the important case of Poisson measures. The product and Wick calculus are developed on this context. We provide formulas for the change of the generalized Appell system under a transformation of the measure. The L² structure for the Poisson measure, compound Poisson and Gamma measures are elaborated. We exhibit the chaos decomposition using the Fock isomorphism. We obtain the representation of the creation, annihilation operators. We construct two types of differential geometry on the configuration space over a differentiable manifold. These two geometries are related through the Dirichlet forms for Poisson measures as well as for its perturbations. Finally, we construct the internal geometry on the compound configurations space. In particular, the intrinsic gradient, the divergence and the Laplace-Beltrami operator. As a result, we may define the Dirichlet forms which are associated to a diffusion process. Consequently, we obtain the representation of the Lie algebra of vector fields with compact support. All these results extends directly for the marked Poisson spaces.
- Distribution of the retrotransposable element 412 in Drosophila speciesPublication . Cizeron, G.; Lemeunier, F.; Loevenbruck, C.; Brehm, A.; Biemont, C.Copy numbers of sequences homologous to the Drosophila melanogaster retrotransposable element 412, their dis tribution between the chromosome arms and the chromocenter, and whether they contain full-size copies were analyzed for 55 species of the Drosophila genus. Element 412 insertion sites were detected on the chromosome arms of D. melanogaster, Drosophila simulans, and a few species of the obscura group, but the chromocenter was labeled in almost all species. The presence of element 412 sequences in the majority of species shows that this element has a long evolutionary history in Drosophilidae, although it may have recently invaded the chromosomes in some species, such as D. simulans. Differences in copy number between species may be due to population size or specific endogenous or environmental factors and may follow the worldwide invasion of the species. Putative full-length copies were detected in the chromocenters of some species with no copies on the chromosome arms, suggesting that the chromocenter may be a shelter for such copies and not only for deleted ones.
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