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See detailEvidence for short-term variations in two O-type stars
De Becker, Michaël ULg; Linder, Natacha ULg; Rauw, Grégor ULg

in Information Bulletin on Variable Stars (2008), 5841

Only a few O-type stars are known to display short-term (a fraction of a day) variations. Intense spectroscopic monitoring of the ON8V star HD 13268 revealed low amplitude variations with periods of ... [more ▼]

Only a few O-type stars are known to display short-term (a fraction of a day) variations. Intense spectroscopic monitoring of the ON8V star HD 13268 revealed low amplitude variations with periods of several hours. In addition, observations of the SB1 system HD 15137 revealed variations on a time scale of a few hours. We consider these stars to be a good candidates for non radial pulsations, even though variations related to inhomogeneities in a circumstellar disk can not be rejected. [less ▲]

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See detailEvidence for significant overlap between common risk variants for Crohn's disease and ankylosing spondylitis.
Laukens, Debby; Georges, Michel ULg; Libioulle, Cécile ULg et al

in PLoS ONE (2010), 5(11), 13795

BACKGROUND: A multicenter genome-wide association scan for Crohn's Disease (CD) has recently reported 40 CD susceptibility loci, including 29 novel ones (19 significant and 10 putative). To gain insight ... [more ▼]

BACKGROUND: A multicenter genome-wide association scan for Crohn's Disease (CD) has recently reported 40 CD susceptibility loci, including 29 novel ones (19 significant and 10 putative). To gain insight into the genetic overlap between CD and ankylosing spondylitis (AS), these markers were tested for association in AS patients. PRINCIPAL FINDINGS: Two previously established associations, namely with the MHC and IL23R loci, were confirmed. In addition, rs2872507, which maps to a locus associated with asthma and influences the expression of the ORMDL3 gene in lymphoblastoid cells, showed a significant association with AS (p = 0.03). In gut biopsies of AS and CD patients, ORMDL3 expression was not significantly different from controls and no correlation was found with the rs2872507 genotype (Spearman's rho: -0.067). The distribution of p-values for the remaining 36 SNPs was significantly skewed towards low p-values unless the top 5 ranked SNPs (ORMDL3, NKX2-3, PTPN2, ICOSLG and MST1) were excluded from the analysis. CONCLUSIONS: Association analysis using risk variants for CD led to the identification of a new risk variant associated with AS (ORMDL3), underscoring a role for ER stress in AS. In addition, two known and five potentially relevant associations were detected, contributing to common susceptibility of CD and AS. [less ▲]

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See detailEvidence For Soil Water Control On Carbon And Water Dynamics In European Forests During The Extremely Dry Year: 2003
Granier, A.; Reichstein, M.; Breda, N. et al

in Agricultural and Forest Meteorology (2007), 143(1-2),

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See detailEvidence For Specific And Non-Covalent Binding Of Lipids To Natural And Recombinant Mycobacterium Bovis Bcg Hsp60 Proteins, And To The Escherichia Coli Homologue Groel
De Bruyn, J.; Soetaert, K.; Buyssens, P. et al

in Microbiology-Sgm (2000), 146

Heat-shock proteins (Hsps) from various origins are known to share a conserved structure and are assumed to be key partners in the biogenesis of proteins. Fractionation of the mycobacterial Hsp60, a 65 ... [more ▼]

Heat-shock proteins (Hsps) from various origins are known to share a conserved structure and are assumed to be key partners in the biogenesis of proteins. Fractionation of the mycobacterial Hsp60, a 65 kDa protein also called Cpn60, from Mycobacterium bovis BCG zinc-deficient culture filtrate on phenyl-Sepharose followed by Western blotting revealed the existence of four Hsp60-1 and Hsp60-2 forms, based on their hydrophobicity behaviour. Hsp60-2 species were further purified by ion-exchange chromatography and partial amino acid sequences of cyanogen bromide (CNBr) peptides of purified Hsp60-2 species showed identity with the amino acid sequence deduced from the hsp60-2 gene, indicating that the various Hsp60-2 forms are encoded by the same gene. In addition, the mycobacterial Hsp60-2 was overexpressed in E. coli using the pRR3Hsp60-2 plasmid and analysed on phenyl-Sepharose. The elution pattern of the recombinant Hsp60-2, as well as that of Escherichia coli GroEL, was similar to that of the native Hsp60-2 from the culture filtrate of M. bovis BCG and entirely different from that of the mycobacterial antigen 85. Extraction of mycobacterial Hsp60-2 forms, recombinant BCG Hsp60-2 and E. coli GroEL with organic solvents releases various amounts of non-covalently bound lipids. The presence of lipids on Hsp60-2 was confirmed by labelling M. bovis BCG with radioactive palmitate. The radioactivity was specifically associated with Hsp60 in the aqueous phase and the 19 and 38 kDa lipoproteins in the Triton X-114 phase. Analysis of the lipids extracted from purified Hsp60-2, recombinant BCG Hsp60-2 and E. coli GroEL by TLC showed the same pattern for all the samples. Acid methanolysis of the lipids followed by GC analysis led to the identification of C(16:0), C(18:0) and C(18:1) as the major fatty acyl constituents, and of methylglycoside in these proteins. Altogether, these data demonstrate that lipids are non-covalently bound to Hsp60-2 and homologous proteins. [less ▲]

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See detailEvidence For The Assignment Of Two Strains Of Splv To The Genus Potyvirus Based On Coat Protein And 3' Non-Coding Region Sequence Data
Colinet, Dominique; Kummert, Jean; Lepoivre, Philippe ULg

in Virus Research (1997), 49(1), 91-100

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See detailEvidence for the association between human thymic MHC class I molecules and a dominant neurohypophysial thymic peptide
Geenen, Vincent ULg; Vandersmissen, Eric; Martens, Henri ULg et al

in Journal of Immunology (1993), 150

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See detailEvidence for the efficacy of preventive means for low back pain
Muller, G; Burton, AK; Balague, F et al

in Physioscience (2005), 1

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See detailEvidence for the existence of pathogenicity determinants in the Long Terminal Repeats (LTRs) of the Bovine Leukemia Virus (BLV) genome
Rodriguez, Sabrina ULg; Trono, K.; Jones, L.R.

in AIDS Research and Human Retroviruses (2011), 8(1), 26

Evidence for the existence of pathogenicity determinants in the Long Terminal Repeats (LTRs) of the Bovine Leukemia Virus (BLV) genome Sabrina M. Rodríguez1*, Karina Trono2, Leandro R. Jones3 1 Molecular ... [more ▼]

Evidence for the existence of pathogenicity determinants in the Long Terminal Repeats (LTRs) of the Bovine Leukemia Virus (BLV) genome Sabrina M. Rodríguez1*, Karina Trono2, Leandro R. Jones3 1 Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA) , University of Liège (ULg), Belgium. 2 Instituto de Virología, CICVyA, Instituto Nacional de Tecnología Agropecuaria INTA-Castelar, CC 25 (1712), Castelar. 3 División de Biología Molecular, Estación de Fotobiología Playa Unión, CC 15, Rawson, Chubut 9103, Argentina. *E-mail: sabrina.rodriguez@ulg.ac.be The majority of BLV-infected animals are asymptomatic carriers (AL) while about 30% develop a benign persistent lymphocytosis (PL). Fatal lymphosarcoma (LS) occurs in 5% of infected animals. The genetic basis of these diverse outcomes of BLV infection is still unknown. Viral LTRs constitute a genetic determinant of pathogenesis for other retroviruses. However, this possibility has never been tested for BLV. Analyses to test correlation between clinical and genotypic traits across species must be corrected by including the group phylogeny. Otherwise, shared evolutionary history can jeopardize statistical independence. Thus, the influence of BLV LTR genetic variation on the clinical manifestation of the disease was investigated by employing Cladistic and Probabilistic, phylogenetic comparative methods. With this purpose, the 5´LTR region of 40 BLV proviruses from bovines with different clinical presentations (AL, PL, LS) was sequenced. Seven polymorphic positions showing an apparent association with the clinical presentation were identified. A provirus phylogeny was obtained using env gene sequences from 28 of the 40 provirus studied in this work. Both Cladistic and Probabilistic comparative analyses based on the empirical sequence alignment and the provirus phylogeny suggested that positions 41 and 56 might be correlated to the clinical presentation. The probabilistic analysis further indicated an association with the viral pathogenesis for positions 373, 450, 494 and 505, though the corresponding statistical supports were lower in comparison to the supports obtained for positions 41 and 56. These observations indicate that the BLV LTRs might contain pathogenicity determinants. [less ▲]

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See detailEvidence for the expression of growth hormone receptors in human placenta
Frankenne, Francis; Alsat, Eliane; Scippo, Marie-Louise ULg et al

in Biochemical and Biophysical Research Communications (1992), 182(2), 481-486

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See detailEvidence For The Occurrence Of Endophytic Prokaryotic Contaminants In Micropropogated Plantlets Of Prunus Cerasus Cv. 'Montmorency'
Kamoun, R.; Lepoivre, Philippe ULg; Boxus, P.

in Plant Cell, Tissue & Organ Culture (1998), 52(1-2),

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See detailEvidence for the presence of N-methyl-D-aspartate receptors in the ventral tegmental area of the rat : an electrophysiological in vitro study
Seutin, Vincent ULg; Verbanck, Paul; Massotte, Laurent ULg et al

in Brain Research (1990), 514(1), 147-150

Extracellular recordings were obtained from spontaneously active, presumed dopaminergic neurons of the ventral tegmental area (VTA) of the rat in a slice preparation. Bath-applied N-methyl-D-aspartate ... [more ▼]

Extracellular recordings were obtained from spontaneously active, presumed dopaminergic neurons of the ventral tegmental area (VTA) of the rat in a slice preparation. Bath-applied N-methyl-D-aspartate (NMDA) (1-20 microM) activated all neurons tested (n = 36). This effect was clearly concentration-dependent (n = 14), quickly reversible and reproducible. No bursting type of discharge was observed during NMDA infusion. The NMDA receptor blocker DL-2-amino-5-phosphonovaleric acid (50 microM) reversibly antagonized the increase in cell firing produced with 10 microM NMDA by 83.5 +/- 3% (mean +/- S.E.M.) (n = 8, P less than 0.05). Lowering the Mg2+ concentration of the perfusion fluid to one-third of its normal value significantly enhanced the excitatory effect of 5 microM NMDA (n = 7, P less than 0.05), but not of 500 nM carbachol (n = 6). Finally, NMDA did not modify the sensitivity of dopaminergic autoreceptors of VTA neurons (n = 8), when compared to controls (n = 10). These observations strongly support the presence of specific NMDA receptors in the VTA. [less ▲]

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See detailEvidence for transplacental transmission of the current wild-type strain of bluetongue virus serotype-8 in cattle
Desmecht, Daniel ULg; Vanden Bergh, Raphaël ULg; Sartelet, Arnaud ULg et al

in Veterinary Record : Journal of the British Veterinary Association (2008), 163

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See detailEvidence for very large-scale coherent orientations of quasar polarization vectors
Hutsemekers, Damien ULg

in Astronomy and Astrophysics (1998), 332

On the basis of a new sample of quasar optical polarization measurements, we have found that, in a region of the sky, the quasar polarization vectors are not randomly oriented as naturally expected, but ... [more ▼]

On the basis of a new sample of quasar optical polarization measurements, we have found that, in a region of the sky, the quasar polarization vectors are not randomly oriented as naturally expected, but appear concentrated around one preferential direction. In order to verify this surprising although preliminary result, we have compiled a large sample of quasar polarization measurements from the literature. With quite severe criteria to eliminate at best the contamination by our Galaxy, a sample of 170 quasars with good quality polarization measurements has been defined. Maps in redshift slices reveal a few regions where the polarization vectors are apparently aligned. To handle the problem more quantitatively, non-parametric 3D statistical tests were designed, as well as a method for visualizing spatially the results. The significance is evaluated through Monte-Carlo simulations. Applied to our sample of 170 polarized quasars, two different statistical tests provide evidence, with significance levels of 0.005 and 0.015 respectively, that the optical polarization vectors of quasars are not randomly distributed over the sky but are coherently oriented on very large spatial scales. This orientation effect appears spatially delimited in the 3D Universe, mainly occuring in a few groups of 10-20 objects. The polarization vectors of objects located along the same line of sight but at different redshifts do not appear accordingly aligned. Essentially for this reason, instrumental bias and contamination by interstellar polarization in our Galaxy are unlikely to be responsible for the observed effect. The very large scale at which this local orientation effect is observed indicates the presence of correlations in objects or fields on spatial scales ~ 1000 h(-1) Mpc at redshifts z =~ 1-2, suggesting an effect of cosmological importance. Several possible and testable interpretations are discussed. Tables~2 and 3 are also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html [less ▲]

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See detailEvidence for violent ejection of nebulae from massive stars
Hutsemekers, Damien ULg

in Astronomy and Astrophysics (1994), 281(Letters), 81-84

We report the results of a systematic search for nebulae around Luminous Blue Variable LBVs) and the discovery of a strong correlation between the mass of the nebulae and the luminosity of the central ... [more ▼]

We report the results of a systematic search for nebulae around Luminous Blue Variable LBVs) and the discovery of a strong correlation between the mass of the nebulae and the luminosity of the central stars. This correlation holds for both the dust and ionized gas masses of the nebulae. The existence of a 'nebular mass-stellar luminosity' relation and the fact that not all LBVs are presently associated with a nebula give evidence against a continuous mass-loss mechanism for the formation of these nebulae. Further, the good agreement found between the observed relation and predictions by Maeder (1989), suggests that all these nebulae may be due to a violent ejection of matter caused by an instability of structural origin. [less ▲]

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See detailEvidence for vortex staircases in the whole angular range due to competing correlated pinning mechanisms
Silhanek, Alejandro ULg; Civale, L.; Candia, S. et al

in Physical Review. B : Condensed Matter (1999), 59(21), 13620-13623

We present measurements of the angular dependence of the irreversible magnetization of YBa2Cu3O7 single crystals with columnar defects inclined with respect to the c axis. At high fields a sharp maximum ... [more ▼]

We present measurements of the angular dependence of the irreversible magnetization of YBa2Cu3O7 single crystals with columnar defects inclined with respect to the c axis. At high fields a sharp maximum centered at the tracks direction is observed. At low fields we identify a lock-in phase characterized by an angle-independent pinning strength and observe an angular shift of the peak towards the c axis that originates in the misalignment between vortices and applied field in anisotropic materials. The interplay among columnar defects, twins, and intrinsic pinning by the ab planes generates a variety of staircase structures. We show that correlated pinning dominates for all orientations of the applied field. [S0163-1829(99)09417-5]. [less ▲]

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See detailEvidence for wastewater influence in a low impacted area throughout stable isotope analyses of the limpet Patella caerulea and epilithic biofilms
Vermeulen, Simon ULg; Lepoint, Gilles ULg; Gobert, Sylvie ULg

Poster (2009, January)

Eutrophication is considered to be one of the main threats to marine environments leading to changes in trophic status of ecosystems and alteration of biological diversity. Carbon and Nitrogen stable ... [more ▼]

Eutrophication is considered to be one of the main threats to marine environments leading to changes in trophic status of ecosystems and alteration of biological diversity. Carbon and Nitrogen stable isotopes analyses were performed on the limpet Patella caerulea and one of its food sources (epilithic biofilms) to assess their potential as early indicators of eutrophication. Samples were seasonally collected in 2005-2006 on five locations gradually exposed to urban sewage in the Calvi Bay and in the Marseilles harbour. Stable isotope signatures of Patella caerulea muscles exhibited steady site - specific values over seasons. In contrast to this time – integrated signal, wide variations in biofilm values show that either composition or isotopic ratios of food sources may vary greatly in time and space. Elevated δ15N values of limpets and biofilms, typical of wastewater influence but unrelated to nitrogen loads, indicate the biological availability of sewage-derived nitrogen in the Calvi Bay and the Marseilles harbour. A reference level of δ15N values is rapidly reached with increasing depth that indicates the limited vertical extent of pollution in the Calvi Bay. [less ▲]

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See detailEvidence for widespread endemism among Antarctic micro-organisms
Vyverman, Wim; Verleyen, Elie; Wilmotte, Annick ULg et al

in Polar Science (2010), 4

Understanding the enormous diversity of microbes, their multiple roles in the functioning of ecosystems, and their response to large-scale environmental and climatic changes, are at the forefront of the ... [more ▼]

Understanding the enormous diversity of microbes, their multiple roles in the functioning of ecosystems, and their response to large-scale environmental and climatic changes, are at the forefront of the international research agenda. In Antarctica, where terrestrial and lacustrine environments are predominantly microbial realms, an active and growing community of microbial ecologists is probing this diversity and its role in ecosystem processes. In a broader context, this work has the potential to make a significant contribution to the long-standing debate as to whether microbes are fundamentally different from macroorganisms in their biogeography. According to the ubiquity hypothesis, microbial community composition is not constrained by dispersal limitation and is solely the result of species sorting along environmental gradients. However, recent work on several groups of microalgae is challenging this view. Global analyses using morphology-based diatom inventories have demonstrated that, in addition to environmental harshness, geographical isolation underlies the strong latitudinal gradients in local and regional diversity in the Southern hemisphere. Increasing evidence points to a strong regionalization of diatom floras in the Antarctic and sub- Antarctic regions, mirroring the biogeographical regions that have been recognized for macroorganisms. Likewise, the application of molecular-phylogenetic techniques to cultured and uncultured diversity revealed a high number of Antarctic endemics among cyanobacteria and green algae. Calibration of these phylogenies suggests that several clades have an ancient evolutionary history within the Antarctic continent, possibly dating back to 330 Ma. These findings are in line with the current view on the origin of Antarctic terrestrial metazoa, including springtails, chironomids and mites, with most evidence suggesting a long history of geographic isolation on a multi-million year, even pre-Gondwana break-up timescale [less ▲]

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See detailEvidence of a changing size-frequency distribution of landslides in the Kyrgyz Tien Shan, Central Asia
Schlögel, Romy; Torgoev; De Marneffe, Cédric et al

in Earth Surface Processes & Landforms (2011), 36/12

There is a strong possibility that environmental change (whether climate or land use) will be manifest as changes in the size–frequency distribution of landslides. Here, evidence is presented for this ... [more ▼]

There is a strong possibility that environmental change (whether climate or land use) will be manifest as changes in the size–frequency distribution of landslides. Here, evidence is presented for this from western Kyrgyzstan, Central Asia. Remote sensing and spatial analysis have been applied to map mass movements in the central part of the Maily‐Say Valley and to detect recent landslide activations. The evolution of landslide activity over the past 50 years has been analysed on the basis of pre‐existing landslide maps and new analyses of aerial photographs as well as Quickbird images. Five inventories were produced for the years 1962 (based on the existing map of 1962 and aerial photographs of 1962), 1984 (based on the existing map of 1977 and aerial photographs of 1984), 1996 (based on aerial photographs of 1996), 2002 (based on the existing map of 2003 and Quickbird imagery of 2002) and 2007 (based on Quickbird imagery of 2007). The geomorphologic features contained in the catalogues represent the landslide bodies observed from remote imagery of the corresponding year. Mapped landslides are generally considered as the result of a series of slope failure events. Size–frequency analyses applied to the five landslide inventories show that both the number and size of unstable slopes increased from 1962 (162 objects) to 2007 (208 objects) and the power‐law exponent decreased over time. This changing power‐law exponent may indicate that landslide‐related hazards are increasing. This tendency is documented in more detail for two active landslide zones, one in the main valley and one located to the west of it. Landslide detection methods were used to assist the evolution of slope instabilities. Choosing appropriate thresholds, the image subtraction method based on normalized difference vegetation index (NDVI) allowed accurate detection of new sliding activation in these two zones. This confirmed the results of the more extensive survey that there is a systematic shift in power law exponents and size–frequency distributions for Central Asian landslides. [less ▲]

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