Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailCalcium-dependent phosphorylation processes control brain aromatase in quail
Balthazart, Jacques ULg; Baillien, Michelle; Charlier, Thierry ULg et al

in European Journal of Neuroscience (2003), 17(8), 1591-1606

Increased gene transcription activated by the binding of sex steroids to their cognate receptors is one important way in which oestrogen synthase (aromatase) activity is regulated in the brain. This ... [more ▼]

Increased gene transcription activated by the binding of sex steroids to their cognate receptors is one important way in which oestrogen synthase (aromatase) activity is regulated in the brain. This control mechanism is relatively slow (hours to days) but recent data indicate that aromatase activity in quail preoptic-hypothalamic homogenates is also rapidly (within minutes) affected by exposure to conditions that enhance Ca2+-dependent protein phosphorylation. We demonstrate here that Ca2+-dependent phosphorylations controlled by the activity of multiple protein kinases including PKC, and possibly also PKA and CAMK, can rapidly down-regulate aromatase activity in brain homogenates. These phosphorylations directly affect the aromatase molecule itself. Western blotting experiments on aromatase purified by immunoprecipitation reveal the presence on the enzyme of phosphorylated serine, threonine and tyrosine residues in concentrations that are increased by phosphorylating conditions. Cloning and sequencing of the quail aromatase identified a 1541-bp open reading frame that encodes a predicted 490-amino-acid protein containing all the functional domains that have been previously described in the mammalian and avian aromatase. Fifteen predicted consensus phosphorylation sites were identified in this sequence, but only two of these (threonine 455 and 486) match the consensus sequences corresponding to the protein kinases that were shown to affect aromatase activity during the pharmacological experiments (i.e. PKC and PKA). This suggests that the phosphorylation of one or both of these residues represents the mechanism underlying, at least in part, the rapid changes in aromatase activity. [less ▲]

Detailed reference viewed: 54 (15 ULg)
Peer Reviewed
See detailCalcium-dependent potassium channels.
Drion, Guillaume ULg; Philippart, Fabian ULg; Sepulchre, Rodolphe ULg et al

in Jaeger, Dieter; Jung, Ranu (Eds.) Encyclopedia of Computational Neuroscience (2015)

Detailed reference viewed: 81 (26 ULg)
Peer Reviewed
See detailCalcium-induced conformational changes of the elicitor and membrane-active fengycin
Nasir, Mehmet Nail ULg; Lins, Laurence ULg; Ongena, Marc ULg et al

Poster (2012, April)

Fengycin is a natural lipopeptide synthetized by Bacillus subtilis strains. It is characterized by strong antifungal and low hemolytic activities. It seems also play a role in the promoting of elicitor ... [more ▼]

Fengycin is a natural lipopeptide synthetized by Bacillus subtilis strains. It is characterized by strong antifungal and low hemolytic activities. It seems also play a role in the promoting of elicitor activities of other compounds. The target of the biological activities of fengycin is supposed to be plasma membrane of sensitive cells. Even though the natural fengycin from has been discovered 25 years ago, nowadays, there is an increase of interest for this compound because of its potent applications. Until 15 years ago, the primary structure of fengycin was a matter of open debate before the publication of the corrected structure obtained by nuclear magnetic resonance and mass spectroscopy techniques. Although the infrared and ultraviolet absorption spectra of the lipopeptide were measured, no detailed analysis of these data was performed probably because of the unconventional sequence of the lipopeptide making these kinds of analyses complicated. In this work, our attempt was to analyze the conformational properties of fengycin as well as the calcium-induced changes using two complementary spectroscopic methods, Fourrier transformed infrared spectroscopy (FTIR) and circular dichroism (CD). In a first step, we have characterized the conformational properties of pure fengycin. The lipopeptide adopts turn conformation in trifluoroethanol, a membrane-mimicking solvent. D-aminoacids seem to be involved in intra molecular hydrogen bonds. In a second step, we have investigated the role played by Ca2+ ions on the possible conformational changes of fengycin. The addition of calcium gives rise to important modifications of the conformation. As fengycin has two glutamate residues, calcium is supposed to bind to their side chains. In conclusion, we have demonstrated that the conformation of fengycin is closely depending of the environment and the presence of calcium ions play an important role on the conformational changes of the lipopeptide. Moreover, spectra obtained both FTIR and CD methods ascertain the presence of turn conformation. [less ▲]

Detailed reference viewed: 89 (9 ULg)
Full Text
Peer Reviewed
See detailCalcium-Iron Oxide as Energy Storage Medium in Rechargeable Oxide Batteries
Berger, Cornelius M.; Mahmoud, Abdelfattah ULg; Hermann, Raphaël ULg et al

in Journal of the American Ceramic Society (2016)

Rechargeable oxide batteries (ROB) comprise a regenerative solid oxide cell (rSOC) and a storage medium for oxygen ions. A sealed ROB avoids pumping loss, heat loss, and gas purity expenses in comparison ... [more ▼]

Rechargeable oxide batteries (ROB) comprise a regenerative solid oxide cell (rSOC) and a storage medium for oxygen ions. A sealed ROB avoids pumping loss, heat loss, and gas purity expenses in comparison with conventional rSOC. However, the iron oxide base storage medium degrades during charging– discharging cycles. In comparison, CaFe3O5 has improved cyclability and a high reversible oxygen storage capacity of 22.3 mol%. In this study, we analyzed the redox mechanism of this compound. After a solid-state synthesis of CaFe3O5, we verified the phase composition and studied the redox reaction by means of X-ray diffraction, Mossbauer spectrometry, and scanning electron microscopy. Results show a great potential to operate the battery with this storage material during multiple charging–discharging cycles. [less ▲]

Detailed reference viewed: 34 (2 ULg)
Full Text
Peer Reviewed
See detailCalcium-vitamin D supplementation in clinical trials of osteoporosis should be titrated on the basis of pre-study assessments
Reginster, Jean-Yves ULg; Diez-Perez, A.; Ortolani, S. et al

in Osteoporosis International (2002), 13(S1), 24

Detailed reference viewed: 12 (3 ULg)
Peer Reviewed
See detailIl calcolo strutturale per i monumenti: la rivista Restauro e l’evoluzione nel corso degli ultimi tre decenni del XX secolo
Rapalo, Maria Chiara ULg

in History of Engineering. International Conference on History of Engineering. V Convegno di Storia dell'Ingegneria. vol. I (2014, May)

The consolidation of masonry structures of the buildings that belong the architectural and environmental heritage is one of the core actions in the set of operations that takes the name of 'restoration ... [more ▼]

The consolidation of masonry structures of the buildings that belong the architectural and environmental heritage is one of the core actions in the set of operations that takes the name of 'restoration', whose goal is the preservation of cultural heritage. In modern times, there is a false dichotomy between "restoration" and "structural reinforcement". The one follows rules taken from different charters, declarations and conventions, developed over time, and the other, instead, is geared to prepare measures to strengthen and secure buildings that require an adjustment or a static improvement. But the common practice, often led to the creation of consolidation works neglecting the time-material interactions and instances of the historical artifact, even through a non-critical use of new materials imposed by the market. Roberto Di Stefano wrote many books and essays on these topics and many significant contributions emerge in the journal Restauro, where, in the period between 1972 and 2003, considerable structural engineers gave their contribution dealing with various structural aspects in relation to the most appropriate methodology for analysis and calculation. In the light of the instructions contained in Restauro, the contribution given to structural calculations for monuments in relation to the obtained results and the problems arising in the last thirty years of the XX century, is going to be examined. [less ▲]

Detailed reference viewed: 29 (1 ULg)
Full Text
Peer Reviewed
See detailCalcul d'ossatures et Assembleges : Considération Economiques
Anderson, D.; Colson, A.; Jaspart, Jean-Pierre ULg

in Constructions Métalliques (1994), (1),

Detailed reference viewed: 41 (0 ULg)
Full Text
Peer Reviewed
See detailCalcul d'un assemblage par platine comportant quatre boulons par rangée
Couchaux, Maël; Demonceau, Jean-François ULg; Weynand, Klaus

in Construction Métallique (2015), 2

Les assemblages de continuité par platine d’extrémité comportent très souvent 2 boulons par rangée. Cependant, lorsque la hauteur de l’assemblage devient importante (supérieure à 600 mm) ou lorsqu’il ... [more ▼]

Les assemblages de continuité par platine d’extrémité comportent très souvent 2 boulons par rangée. Cependant, lorsque la hauteur de l’assemblage devient importante (supérieure à 600 mm) ou lorsqu’il n’est pas possible d’utiliser une rangée extérieure, 4 boulons peuvent être mis en place au niveau des rangées se situant directement sous la semelle (voir Figure 1). Cette disposition constructive peut permettre d’augmenter significativement la résistance de la rangée intérieure tendue si l’épaisseur de la platine est suffisante ainsi que la résistance à l’effort tranchant de l’assemblage. La NF P 22-460 [4] donnait une méthode de calcul de la résistance d’une rangée tendue comportant 4 boulons dans le paragraphe 9.3. La partie 1-8 de l’Eurocode 3 [1] permet quant à elle de prédire la résistance d’un assemblage via la méthode des composantes et, en particulier, de déterminer la résistance en traction de rangées de boulons à partir de la méthode des tronçons en T décrite dans le paragraphe 6.2.4. Cependant, cette méthode des tronçons en T ne couvre que les rangées comportant 2 boulons ; aucune information n’est donc fournie pour les rangées présentant 4 boulons. Néanmoins la méthode des composantes telle que recommandée dans l’Eurocode 3 est une méthodologie générale qui peut être adaptée à des assemblages comportant 4 boulons par rangée horizontale moyennant une validation expérimentale. Une telle adaptation est proposée par Demonceau et al [7] afin de déterminer la résistance en traction de rangées comportant 4 boulons. Cette méthode, développée dans le cadre d’un projet national Allemand (Projektbesprechung AIF-Forschungsvorhaben 15059N) est fondée sur la méthode des tronçons en T susmentionnée et est donc similaire à celle proposée pour le calcul de la résistance en traction de rangées comportant 2 boulons. Cette méthode a également été validée par comparaison à des résultats d’essais et implémentée dans le logiciel CoP [8]. Cette méthode a d’ailleurs été introduite dans les recommandations de la CNC2M pour le dimensionnement des assemblages selon l’EN 1993-1-8 [5]. L’objet de cette note technique est de présenter une méthode de calcul basée sur les références [6], [7] et [9] permettant d’évaluer la résistance et la rigidité d’assemblages par platine comportant 4 boulons par rangée. Les spécificités de l’Annexe Nationale française concernant les diagrammes triangulaires sont par ailleurs rappelées. Cette présentation de la méthode de calcul est suivie d’un exemple d’application. L’origine de ces nouvelles formulations est par ailleurs expliquée en annexe A.1. Enfin, la comparaison entre les résultats d’essais et ceux obtenus à partir de cette méthode est présentée en annexe A.2. [less ▲]

Detailed reference viewed: 106 (1 ULg)
See detailCalcul d’un bateau porte de 25 m (calcul structurel – LBR5)
Rigo, Philippe ULg; Constantinescu, A.

Report (2009)

Detailed reference viewed: 82 (0 ULg)
See detailCalcul d'un double fond-Rapport R&D7
Rigo, Philippe ULg

Report (2004)

Detailed reference viewed: 17 (0 ULg)
See detailCalcul d'un pont canal métallique sur le canal du Centre
Rigo, Philippe ULg

Report (1997)

Detailed reference viewed: 45 (0 ULg)
See detailCalcul d'une passerelle mobile
Rigo, Philippe ULg; Pircalabu, Eugen

Report (2006)

Detailed reference viewed: 53 (3 ULg)
See detailCalcul de l’aléa sismique pour une région dans le Tien-Shan Central, étude in situ et modélisation numérique dynamique de la réponse sismique de sites de bassin de retenue.
Lamair, Laura ULg

Master's dissertation (2012)

Kyrgyzstan is situated in the heart of the Tien Shan. During the last two centuries, several M>7 earthquakes occurred in this country. Therefore, a good knowledge of seismic hazard in this area is ... [more ▼]

Kyrgyzstan is situated in the heart of the Tien Shan. During the last two centuries, several M>7 earthquakes occurred in this country. Therefore, a good knowledge of seismic hazard in this area is essential, not only at regional scale but also at local scale. First, this work presents a detailed analysis of seismic hazard in the Central Tien Shan. Several seismic hazard map have been made but none of them include paleoseismic data. Our maps are based on previous studies of probabilistic seismic hazard of the Kyrgyz Tien Shan (Abdrakhmatov et al., 2003). We integrate in our calculation the palaeoseismicity of the Talas Fergana Fault. It allows us to take into consideration strong earthquakes with high return periods. The final results are presented as maps with different return periods (100, 200, 475, 1000, 2000, 5000 and 10000 years). The outcomes are discussed in comparison with previous results, with GSHAP predictions (Ulomov et al., 1999) and with probabilistic seismic hazard map (Abdrakhmatov et al., 2003). The purpose of the second part of this study is the assessment of local seismic hazard of Tuyuk-Suu and Taldy-Bulak "D" tailings, both located in the Minkush valley. First, seismic wave amplifications are determined by means of spectral ratios of the horizontalto- vertical (H/V) components acquired through ambient noise measurements. Secondly, a dynamic modeling of the two tailings is performed. It is based on peak ground acceleration calculated previously for a return period of 1000 years. The dynamic modeling gives Fourier spectra for several histories. Spectral ratios obtained from dynamic modeling are compared with H/V measurement in order to estimate site effects. [less ▲]

Detailed reference viewed: 61 (12 ULg)
See detailCalcul de l'équilibre calcocarbonique des eaux sur calculatrice de poche.
Wuidar, A.; Marcoen, Jean Marie ULg

in Tribune de l'Eau (La) (1994), 47(1), 11-13

Detailed reference viewed: 35 (0 ULg)
Full Text
See detailCalcul de la marge et du prix
Van Caillie, Didier ULg

Learning material (2007)

This seminar presents the key elements allowing to estimate judiciously the main costs induced by a new activity and to establish a price that is both reflecting the internal cost structure and the ... [more ▼]

This seminar presents the key elements allowing to estimate judiciously the main costs induced by a new activity and to establish a price that is both reflecting the internal cost structure and the potential of the market. This seminar is adapted to activities taking place in the art industry. [less ▲]

Detailed reference viewed: 154 (11 ULg)
Full Text
Peer Reviewed
See detailCalcul de la propagation d'une onde de rupture de barrage
Pirotton, Michel ULg

in Tribune de l'Eau (La) (1991), 44(551), 23-31

Detailed reference viewed: 44 (0 ULg)
Full Text
See detailCalcul de la résistance au feu d'ouvrages d'art en intégrant l'éclatement du béton
Franssen, Jean-Marc ULg; Hanus, François ULg; Dotreppe, Jean-Claude ULg

Scientific conference (2007, July 06)

Les ouvrages en béton présentent en général une bonne résistance au feu. Toutefois, dans certaines situations, l'apparition de phénomènes d'éclatement peut mener à une réduction rapide et marquée de la ... [more ▼]

Les ouvrages en béton présentent en général une bonne résistance au feu. Toutefois, dans certaines situations, l'apparition de phénomènes d'éclatement peut mener à une réduction rapide et marquée de la résistance des éléments concernés. Les tunnels, qui sont souvent soumis à des incendies de très forte intensité, subissent très souvent la perte de leurs premières couches intérieures pouvant conduire à la mise à nu des armatures. dans cet article, on montre comment le logiciel SAFIR peut être utilisé pour effectuer une analyse de risque en intégrant des valeurs plausibles de l'éclatement. ce concept sera illustré par l'examen d'une structure particulière. [less ▲]

Detailed reference viewed: 448 (12 ULg)
See detailCalcul de la résistance au feu des structures mixtes acier-béton
Franssen, Jean-Marc ULg

Conference given outside the academic context (1986)

Detailed reference viewed: 57 (4 ULg)