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See detailThe 2.35 year itch of Cygnus OB2 #9. I. Optical and X-ray monitoring
Nazé, Yaël ULg; Mahy, Laurent ULg; Damerdji, Yassine ULg et al

in Astronomy and Astrophysics (2012), 546

Context. Nonthermal radio emission in massive stars is expected to arise in wind-wind collisions occurring inside a binary system. One such case, the O-type star Cyg OB2 #9, was proven to be a binary only ... [more ▼]

Context. Nonthermal radio emission in massive stars is expected to arise in wind-wind collisions occurring inside a binary system. One such case, the O-type star Cyg OB2 #9, was proven to be a binary only four years ago, but the orbital parameters remained uncertain. The periastron passage of 2011 was the first one to be observable under good conditions since the discovery of binarity. <BR /> Aims: In this context, we have organized a large monitoring campaign to refine the orbital solution and to study the wind-wind collision. <BR /> Methods: This paper presents the analysis of optical spectroscopic data, as well as of a dedicated X-ray monitoring performed with Swift and XMM-Newton. <BR /> Results: In light of our refined orbital solution, Cyg OB2 #9 appears as a massive O+O binary with a long period and high eccentricity; its components (O5-5.5I for the primary and O3-4III for the secondary) have similar masses and similar luminosities. The new data also provide the first evidence that a wind-wind collision is present in the system. In the optical domain, the broad Hα line varies, displaying enhanced absorption and emission components at periastron. X-ray observations yield the unambiguous signature of an adiabatic collision, because as the stars approach periastron, the X-ray luminosity closely follows the 1/D variation expected in that case. The X-ray spectrum appears, however, slightly softer at periastron, which is probably related to winds colliding at slightly lower speeds at that time. <BR /> Conclusions: It is the first time that such a variation has been detected in O+O systems, and the first case where the wind-wind collision is found to remain adiabatic even at periastron passage. [less ▲]

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See detailThe 2.4-A crystal structure of the penicillin-resistant penicillin-binding protein PBP5fm from Enterococcus faecium in complex with benzylpenicillin.
Sauvage, Eric ULg; Kerff, Frédéric ULg; Fonze, E. et al

in Cellular and Molecular Life Sciences : CMLS (2002), 59(7), 1223-32

Penicillin-binding proteins (PBPs) are membrane proteins involved in the final stages of peptidoglycan synthesis and represent the targets of beta-lactam antibiotics. Enterococci are naturally resistant ... [more ▼]

Penicillin-binding proteins (PBPs) are membrane proteins involved in the final stages of peptidoglycan synthesis and represent the targets of beta-lactam antibiotics. Enterococci are naturally resistant to these antibiotics because they produce a PBP, named PBP5fm in Enterococcus faecium, with low-level affinity for beta-lactams. We report here the crystal structure of the acyl-enzyme complex of PBP5fm with benzylpenicillin at a resolution of 2.4 A. A characteristic of the active site, which distinguishes PBP5fm from other PBPs of known structure, is the topology of the loop 451-465 defining the left edge of the cavity. The residue Arg464, involved in a salt bridge with the residue Asp481, confers a greater rigidity to the PBP5fm active site. In addition, the presence of the Val465 residue, which points into the active site, reducing its accessibility, could account for the low affinity of PBP5fm for beta-lactam. This loop is common to PBPs of low affinity, such as PBP2a from Staphylococcus aureus and PBP3 from Bacillus subtilis. Moreover, the insertion of a serine after residue 466 in the most resistant strains underlines even more the determining role of this loop in the recognition of the substrates. [less ▲]

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See detailA 2.5 D finite element model for bending and straightening in continuous casting of steel slabs
Pascon, Frédéric ULg; Cescotto, Serge ULg; Habraken, Anne ULg

in International Journal for Numerical Methods in Engineering (2006), (68), 125-149

This paper presents a bi-dimensional slice model of the continuous casting process developed to focus on the risk of transverse cracking during bending and straightening of steel slabs. The model is based ... [more ▼]

This paper presents a bi-dimensional slice model of the continuous casting process developed to focus on the risk of transverse cracking during bending and straightening of steel slabs. The model is based on the finite element method and it integrates both thermal and mechanical aspects: temperature evolution, solidification, stress and strain developments. Generalized plain strain conditions are applied in the casting direction, allowing taking account of the extraction force applied to the slab as well as strains in this direction. The model also includes an original solution to counteract the generally wrong modelling of slab bulging with such slice models. The model has been applied to an industrial case of slab casting. Some numerical results illustrate the accuracy of the model compared to results of other models, measurements and observations on the caster. Transverse cracks are predicted to be the most likely to occur at the edge on the upper face, at the end of straightening of the slab. This is due to the combination of low ductility of the material with tensile stress and elongation in the casting direction in the straightening zone. This conclusion has been confirmed by the examination of slabs that present transverse cracks. [less ▲]

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See detailA 2.5-Mb contig constructed from Angus, Longhorn and horned Hereford DNA spanning the polled interval on bovine chromosome 1
Wunderlich, K. R.; Abbey, C. A.; Clayton, D. R. et al

in Animal Genetics (2006), 37(6), 592-594

The polled locus has been mapped by genetic linkage analysis to the proximal region of bovine chromosome 1. As an intermediate step in our efforts to identify the polled locus and the underlying causative ... [more ▼]

The polled locus has been mapped by genetic linkage analysis to the proximal region of bovine chromosome 1. As an intermediate step in our efforts to identify the polled locus and the underlying causative mutation for the polled phenotype, we have constructed a BAC-based physical map of the interval containing the polled locus. Clones containing genes and markers in the critical interval were isolated from the TAMBT (constructed from Angus and Longhorn genomic DNA) and CHORI-240 (constructed from horned Hereford genomic DNA) BAC libraries and ordered based on fingerprinting and the presence or absence of 80 STS markers. A single contig spanning 2.5 Mb was assembled. Comparison of the physical order of STSs to the corresponding region of human chromosome 21 revealed the same order of genes within the polled critical interval. This contig of overlapping BAC clones from horned and polled breeds is a useful resource for SNP discovery and characterization of positional candidate genes. [less ▲]

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See detail2.8-Å Structure of penicillin-sensitive D-alanyl carboxypeptidase-transpeptidase from Streptomyces R61 and complexes with β-lactams
Kelly, Judith A; Knox, James R; Moews, Paul C et al

in Journal of Biological Chemistry (1985), 260(10), 6449-6458

The crystallographic structure of the penicillin-sensitive D-alanyl carboxypeptidase-transpeptidase from Streptomyces R61 has been solved to 2.8-A resolution. The 38,000-dalton serine peptidase has two ... [more ▼]

The crystallographic structure of the penicillin-sensitive D-alanyl carboxypeptidase-transpeptidase from Streptomyces R61 has been solved to 2.8-A resolution. The 38,000-dalton serine peptidase has two regions of secondary structure, an alpha/beta cluster, and a region which contains five helical segments. The beta sheet is composed of five beta strands. The tertiary structure has no homology with the classic serine proteases or with the zinc carboxypeptidases. The binding at a common site of three types of beta-lactam (a penicillin, a cephalosporin, a monocyclic beta-lactam) and a desazacyclobutanone has been observed in Fourier difference maps. The binding site sequence is Val-Gly-Ser-Val-Thr-Lys. The beta-lactam ring lies near the enzyme's catalytic serine at position 37, and the C3 substituent of a cephalosporin falls near lysine 40. [less ▲]

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See detail20 ans d'études dans 2 bassins versants boisés en Ardenne
Guillaume, Patricia; Bosman, Bernard ULg; Bazgir, Masoud et al

Diverse speeche and writing (2011)

En Région wallonne, de nombreux sols forestiers se caractérisent par un pH faible et une pauvreté en Ca, P et surtout Mg. Depuis 1991, dans le cadre d’études sur le dépérissement forestier et l’impact de ... [more ▼]

En Région wallonne, de nombreux sols forestiers se caractérisent par un pH faible et une pauvreté en Ca, P et surtout Mg. Depuis 1991, dans le cadre d’études sur le dépérissement forestier et l’impact de mesures de gestion forestière, le laboratoire d’Ecologie Végétale et Microbienne (ULg) étudie l’évolution des concentrations et des flux en éléments minéraux dans les principaux compartiments de deux bassins versants. Ce triptyque résume une partie de ces recherches. [less ▲]

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See detail20 ans de formation ! et demain ?
Morant, Michel ULg

Conference (2011, June 08)

La présentation met en évidence les besoins nouveaux dans les compétences requises pour un gestionnaire de transfert de technologie ou agent de valorisation

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See detail20 ans de valorisation dans l'Espace Wallonie-bruxelles
Morant, Michel ULg

Conference (2011, June 06)

La présentation brosse 2à années d'évolution des universités en Wallonie en matière de 3e mission, et en particulier de la valorisation économique de la recherche

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See detail20 years of NF-kappa B
Chariot, Alain ULg

in Biochemical Pharmacology (2006), 72(9), 1051-1053

We are celebrating this year 20 years of research dedicated to the transcription factor NF-kB. From 1986, the year of its initial identification as a DNA-binding activity for the enhancer of the ... [more ▼]

We are celebrating this year 20 years of research dedicated to the transcription factor NF-kB. From 1986, the year of its initial identification as a DNA-binding activity for the enhancer of the immunoglobulin k light-chain in activated B cells by David Baltimore and colleagues [1] to 2006, almost 20000 papers related to this transcription factor were published, which means three reports per day. This amazing amount of data generated over the years and throughout the world reflects the critical roles played by NF-kB in biology. It is indeed increasingly difficult to find circumstances where NF-kB is not involved at one point. One reason is due to the amazing amount of signals that can activate NF-kB. They include bacterial, viral and fungal products but also inflammatory cytokines, oxidative stress and therapeutically used drugs (as reviewed by Y. Habraken and J. Piette in this issue) and are listed in Tom Gilmore’s website (www.nf-kb.org) (Boston University). Another reason is due to the functional kB sites found in about one hundred genes [2]. These numerous NF-kB target genes play critical roles in cell survival and proliferation, as well as in innate and adaptive immunity, which reflects the essential role of this transcription factor in physiology and diseases. [less ▲]

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See detail20-Nanogold Au20(Td) and Low-Energy Hollow Cages: Void Reactivity
Kryachko, Eugène ULg; Remacle, Françoise ULg; Hoggan, P. E. et al

in Advances in the Theory of Quantum Systems in Chemistry and Physics (2012)

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See detailThe 2006 Adjuvant Trastuzumab Convention in Belgium: 5 years later
VANDERHAEGEN, J; PARIDAENS, R; PICCART, M et al

Poster (2012, December)

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See detail2006, année internationale de la lutte contre la désertification
Ozer, Pierre ULg

Article for general public (2006)

La désertification est considérée comme l'une des problématiques environnementales les plus préoccupantes du XXIe siècle. Par désertification, on entend la dégradation des terres dans les zones arides ... [more ▼]

La désertification est considérée comme l'une des problématiques environnementales les plus préoccupantes du XXIe siècle. Par désertification, on entend la dégradation des terres dans les zones arides, semi-arides et sub-humides sèches par suite de divers facteurs, parmi lesquels les variations climatiques et les activités humaines. Cette dégradation environnementale affecte directement un milliard d'hectares et menace près de 35 % des terres de la planète ainsi que les moyens de subsistance de deux milliards d'individus. Les estimations des pertes financières mondiales dues à la désertification sont colossales, de l'ordre de 40 milliards d'euros par an. [...] [less ▲]

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See detail2006, International Year of Deserts, Desertification and Dust
Ozer, Pierre ULg; Courel, Marie-Françoise; Goudie, Andrew S

in Africa Health (2006), 28(4), 3

Desertification ranks among the major environmental challenges of the 21st century and is defined by the United Nations Convention to Combat Desertification as ‘land degradation in arid, semiarid, and dry ... [more ▼]

Desertification ranks among the major environmental challenges of the 21st century and is defined by the United Nations Convention to Combat Desertification as ‘land degradation in arid, semiarid, and dry subhumid areas resulting from various factors, including climatic variations and human activities’. Currently, desertification affects a total area between 6 million and 12 million square kilometres and generates large loss of income, estimated at US$42 billion each year. Areas threatened by desertification occupy 34% of the Earth’s land area and are home to about 2 billion people. [...] [less ▲]

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See detail2006, l'Europe sans boussole
Defossez, Alexandre ULg; Petit, Nicolas ULg; Candela, Mercedes

Article for general public (2006)

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See detailThe 2007 rifting event in Northern Tanzania studied by C and L-band interferometry
Oyen, Anneleen; Wauthier, Christelle ULg; d'Oreye, Nicolas et al

in ECGS Blue Books (2010)

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See detail2008 : Ritorni coloniali
Curreri, Luciano ULg

in Ilcorsaronero : Rivista salgariana di letteratura popolare (2009), 9

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See detail2009 sera télescopique Le miroir liquide liégeois bientôt installé en Inde
Surdej, Jean ULg

Article for general public (2009)

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See detail2009, Année Internationale de l'Astronomie
Jehin, Emmanuel ULg

Article for general public (2009)

Not Available

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