Details on DARWIN and the Search for Extrasolar Planets
; ; Absil, Olivier
in Deming, Drake; Seager, Sara (Eds.) Scientific Frontiers in Research on Extrasolar Planets (2003)
The direct detection of an earth-like planet close to its parent star is challenging because the signal detected from the parent star is between 10[SUB]9[/SUB] and 10[SUB]6[/SUB] times brighter than the ... [more ▼]
The direct detection of an earth-like planet close to its parent star is challenging because the signal detected from the parent star is between 10[SUB]9[/SUB] and 10[SUB]6[/SUB] times brighter than the signal of a planet in the visual and infrared (IR), respectively. Future space based missions like DARWIN and TPF concentrate on the region between 6 and 18 microns, a region that contains the carbon dioxide, water, and ozone spectral features of the atmosphere. Using several small collecting telescopes and a beam combiner allows us to build an instrument with an angular resolution normally associated with monolithic telescopes of much larger diameters. The relative positions of the telescopes, forming the interferometer, are selected such that when the optical signals, collected by the individual telescopes, are coherently combined, the small angular distance between the planet and the star can be resolved. Different configurations of the free flying interferometer array influence the performance of the nulling array. The concepts for space nulling interferometers and the influence of different schemes of beam combination on the detected signal are investigated. The contribution of background noise to the detected signal is examined. [less ▲]Detailed reference viewed: 78 (0 ULg)
Piracetam Inhibits The Lipid-Destabilising Effect Of The Amyloid Peptide A Beta C-Terminal Fragment
; Lins, Laurence ; et al
in Biochimica et Biophysica Acta-Biomembranes (2003), 1609(1), 28-38
Amyloid peptide (Abeta) is a 40/42-residue proteolytic fragment of a precursor protein (APP), implicated in the pathogenesis of Alzheimer's disease. The hypothesis that interactions between Abeta ... [more ▼]
Amyloid peptide (Abeta) is a 40/42-residue proteolytic fragment of a precursor protein (APP), implicated in the pathogenesis of Alzheimer's disease. The hypothesis that interactions between Abeta aggregates and neuronal membranes play an important role in toxicity has gained some acceptance. Previously, we showed that the C-terminal domain (e.g. amino acids 29-42) of Abeta induces membrane permeabilisation and fusion, an effect which is related to the appearance of non-bilayer structures. Conformational studies showed that this peptide has properties similar to those of the fusion peptide of viral proteins i.e. a tilted penetration into membranes. Since piracetam interacts with lipids and has beneficial effects on several symptoms of Alzheimer's disease, we investigated in model membranes the ability of piracetam to hinder the destabilising effect of the Abeta 29-42 peptide. Using fluorescence studies and 31P and 2H NMR spectroscopy, we have shown that piracetam was able to significantly decrease the fusogenic and destabilising effect of Abeta 29-42, in a concentration-dependent manner. While the peptide induced lipid disorganisation and subsequent negative curvature at the membrane-water interface, the conformational analysis showed that piracetam, when preincubated with lipids, coats the phospholipid headgroups. Calculations suggest that this prevents appearance of the peptide-induced curvature. In addition, insertion of molecules with an inverted cone shape, like piracetam, into the outer membrane leaflet should make the formation of such structures energetically less favourable and therefore decrease the likelihood of membrane fusion. [less ▲]Detailed reference viewed: 10 (0 ULg)
Bronchoalveolar lavage fluids of ventilated patients with acute lung injury activate NF-kB in alveolar epithelial cell line: role of reactive oxygen/nitrogen species and cytokines
Nys, Monique ; Deby, Ginette ; et al
in Nitric Oxide (2003), 9(1), 33-43Detailed reference viewed: 41 (15 ULg)
Des Fleurs de saints à l'odeur de sainteté. L'hagiographie en terres wallonnes,
George, Philippe ; Raschevitch, Sonia
in Dumortier, Jean-Louis; George, Philippe (Eds.) Regards sur le XVIIe siècle. Feuillets de la Cathédrale de Liège. (2003)Detailed reference viewed: 26 (3 ULg)
Molecular dissection of a quantitative trait locus: a phenylalanine-to-tyrosine substitution in the transmembrane domain of the bovine growth hormone receptor is associated with a major effect on milk yield and composition.
; ; et al
in Genetics (2003), 163(1), 253-66
We herein report on our efforts to improve the mapping resolution of a QTL with major effect on milk yield and composition that was previously mapped to bovine chromosome 20. By using a denser chromosome ... [more ▼]
We herein report on our efforts to improve the mapping resolution of a QTL with major effect on milk yield and composition that was previously mapped to bovine chromosome 20. By using a denser chromosome 20 marker map and by exploiting linkage disequilibrium using two distinct approaches, we provide strong evidence that a chromosome segment including the gene coding for the growth hormone receptor accounts for at least part of the chromosome 20 QTL effect. By sequencing individuals with known QTL genotype, we identify an F to Y substitution in the transmembrane domain of the growth hormone receptor gene that is associated with a strong effect on milk yield and composition in the general population. [less ▲]Detailed reference viewed: 36 (8 ULg)
Optimal design of outdoor lighting systems by genetic algorithms - Discussion
in Lighting Research & Technology (2003), 35(3), 278-280Detailed reference viewed: 53 (0 ULg)
Trophic habits and aquatic microhabitat use in gilled immature, paedomorphic and metamorphic Alpine newts (Triturus alpestris apuanus) in a pond in central Italy
Denoël, Mathieu ;
in Belgian Journal of Zoology (2003), 133(2), 95-102
Current evolutionary models suggest that the presence of heterogeneous habitats favours the evolution of polymorphisms. In such cases, alternative phenotypes can coexist because they use different ... [more ▼]
Current evolutionary models suggest that the presence of heterogeneous habitats favours the evolution of polymorphisms. In such cases, alternative phenotypes can coexist because they use different resources. Facultative paedomorphosis is a heterochronic polymorphism in which a morph - the paedomorph - retains larval traits during the adult stage while the other morph - the metamorph - is fully metamorphosed. The aim of this study was to determine the microhabitat use and the diet of Alpine newt paedomorphs, metamorphs and immatures (Triturus alpestris apuanus) coexisting in a small pond in Tuscany, central Italy, i.e. in a habitat where dimorphism is not expected. Although the two adult morphs do not use exactly the same resources, resource partitioning was weaker than in deep Alpine lakes. Nevertheless, the diet of immature gilled newts (larvae) differed from that of adults (metamorphs and paedomorphs). While the larvae eat a large number of planktonic organisms, the adults focus on insect larvae and newt eggs. The differences in resource use favour the coexistence of aquatic juveniles and adults. In the studied pond, facultative paedomorphosis was previously shown to be favoured by a precocious maturity of the paedomorphs. This study shows that the coexistence of paedomorphs and metamorphs may also be supported by some dietary and spatial segregation, although any advantages gained by this pattern are rather limited in the adult stage. [less ▲]Detailed reference viewed: 317 (21 ULg)
Effet de la pression partielle en oxygène sur le métabolisme des chondrocytes bovins en culture
; ; et al
in Revue du Rhumatisme (2003), 70Detailed reference viewed: 4 (1 ULg)
Oxytocin and vasopressin autocrine/paracrine signalling in small cell lung carcinoma.
Conference (2003)Detailed reference viewed: 22 (0 ULg)
Once weekly recombinant human erythropoietin therapy is very efficient after allogeneic peripheral blood stem cell transplantation when started soon after engraftment.
Baron, Frédéric ; Frere, Pascale ; Beguin, Yves
in Haematologica (2003), 88(6), 718-20Detailed reference viewed: 11 (2 ULg)
Quel est le "noyau dur" de la formation en géographie? Le point de vue d'un géographe climatologue.
in Géographes Associés (2003), 27
Which geograpry to teach tomorrow at university? The point of view of a geographer working in climatology and topoclimatology.Detailed reference viewed: 30 (1 ULg)
Mycotoxins in stored Barley (Hordeum vulgare) in Tibet Autonomous Region (People’s Republic of China.
Haubruge, Eric ;
in Mountain Research & Development (2003), 23Detailed reference viewed: 11 (1 ULg)
Internal anatomy of catfishes.
; ; et al
in Kapoor, B. G.; Arratia, G.; Diogo, Rui (Eds.) et al Catfishes (2003)Detailed reference viewed: 66 (2 ULg)
First-principles calculation of the electronic, dielectric, and dynamical properties of CaF2
Verstraete, Matthieu ;
in Physical Review. B : Condensed Matter (2003), 68Detailed reference viewed: 29 (5 ULg)
Conception d'un support télématique à la mise en place du programme de dépistage du cancer du sein.
Husson, Eddy ; Guillaume, Michèle ; Duquesne, Patricia et al
Poster (2003)Detailed reference viewed: 27 (11 ULg)