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See detailValidation of ENVISAT-1 Level-2 Products Related to Lower Atmosphere O3 and NOy Chemistry by a FTIR Quasi-global Network
De Mazière, Martine; Coosemans, Thierry; Barret, Brice et al

in Proceedings of Envisat Validation Workshop, Frascati, Italy, December 9-13, 2002, ESA SP-531, 2003 (2003)

A coordinated action involving eleven stations of the ground -based Network for Detection of Stratospheric Change (NDSC) equipped with Fourier transform infrared (FTIR) instruments was conducted to ... [more ▼]

A coordinated action involving eleven stations of the ground -based Network for Detection of Stratospheric Change (NDSC) equipped with Fourier transform infrared (FTIR) instruments was conducted to contribute to the validation of the three atmospheric chemistry instruments onboard ENVISAT, that are MIPAS, SCIAMACHY and GOMOS. The target products for validation are total columns of O3, CH4, CO and some important NOy species (NO2, HNO3, NO) and the source gas N2O. Together the eleven stations cover the latitudes between 79 °N and 78°S, including polar, mid-latitude and subtropical and tropical locations. The goal is to contribute to the assessment of the data quality of the aforementioned ENVISAT instruments, from a quasi -global perspective. The period of intensive ground-based data collection for the benefit of the ENVISAT Validation Commissioning Phase that is dealt with in the present paper is July 15 to December 1, 2002. The FTIR network involved collected a data set corresponding to an equivalent of approximately 400 days of measurements; about three quarter of the data have already been submitted to the ENVISAT Calval database and are included in the present work. Unfortunately, the distribution of ENVISAT data has been slow and limited. Only a limited number of coincidences has been found for making data inter -comparisons. Therefore, the conclusions drawn in this paper are very preliminary and cover only a limited set of data products from SCIAMACHY only. Our findings up to now concerning the above mentioned target products are the following: (1) SCIAMACHY near infrared operational products (CO, CH4, N 2O) have no scientific meaning yet, (2), the operational SCIAMACHY total vertical O3 column product derived in the ultraviolet window has undergone some improvements with changing versions of the processor(s) but it still underestimates the column by about 5 – 10 %, (3), the operational SCIAMACHY total vertical O3 column product derived in the visible window is unrealistically large, and (4), the operational NO2 total column product from SCIAMACHY seems to largely overestimate the real column, but very few coincidences and large dispersions of the data do inhibit any further conclusion at present. In a next phase, the same ground-based correlative data set will be exploited to further validate the ENVISAT data as soon as more and reprocessed data will be distributed. [less ▲]

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See detailLe contrat de travail sans papier
Kefer, Fabienne ULg

in Le droit des affaires en évolution. Le contrat sans papier (2003)

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See detailTrace elements concentrations in by-caught Norwegian harbour porpoises (Phocoena phocoena): sources of variation and insights in their feeding ecology through stable carbon and nitrogen measurements
Fontaine, Michaël; Siebert, Ursula; Tolley, K. et al

Conference (2003)

Great concern raised from the populations decline observed for the harbour porpoises in the North Atlantic but Norwegian populations remain poorly characterized. Trace elements concentrations (Zn, Cu, Cd ... [more ▼]

Great concern raised from the populations decline observed for the harbour porpoises in the North Atlantic but Norwegian populations remain poorly characterized. Trace elements concentrations (Zn, Cu, Cd, Se, total Hg) have been determined in liver, kidney and muscle of 23 harbour porpoises (Phocoena phocoena) caught in fishing nets along the Norwegian coast. Sources of variation have been examined with a special interest on geographic location and diet modifications analysed through stable isotopes of carbon (δ13C) and nitrogen (δ15N). This study further intend to complete previous feeding ecology knowledge with a combined approach of stable isotopes ratios and metals concentrations as dietary tracers. Norwegian porpoises display mean hepatic concentrations of Zn, Cu and total Hg (96 ± 18; 25 ± 6 ; 15 ± 10 µg.g-1dw respectively) among the lowest in the North-Atlantic. These results suggest that porpoises from this region are less exposed to these metals than others sites such as the North Sea. The low burdens of certain metals (Zn, Cu, Hg) observed make the Norwegian populations suitable to be used as reference level for future ecotoxicological studies on this species. However, renal Cd concentrations (6.7 ± 4.1µg.g-1dw) are twice higher than those from the Southern North Sea. They probably reflect dietary modifications of the porpoises through their range. The low isotopic composition (mean muscle values: d13C=-18.5 ± 0.6 0/00 and δ15N=13.5 ± 1.2 0/00) suggests that Norwegian porpoises feed on more oceanic preys as confirmed by variations of hepatic Hg and renal Cd concentrations. Given that teutophagous marine mammals present higher concentrations of Cd than piscivorous ones. The results obtained lead to the conclusion that the Norwegian porpoises rely on more oceanic squids than those from the North Sea. [less ▲]

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See detailLes interactions entre l'homme et les animaux familiers : quelques champs d'investigation et réflexions méthodologiques
Servais, Véronique ULg; Millot, Jean-Louis

in Baudouin, Claude (Ed.) L'éthologie appliquée aujourd'hui. Tome 3, l'éthologie humaine (2003)

Le paper synthetizes the main studies in the field of human-animal interactions and points to some pitfalls in the methodologies of many researches.

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See detailThe cold atom micromaser in a vertical configuration
Martin, John ULg; Bastin, Thierry ULg

Poster (2003)

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See detailX-Ray spectromicroscopy of clusters heated by fs laser radiation
Faenov, A.Ya.; Magunov, A. I.; Pikuz, T. A. et al

Conference (2003)

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See detailMechanical behaviour of chalk reservoirs: numerical modelling of water sensitivity effects
Collin, Frédéric ULg; Cui, Yu Jun; Schroeder, Christian ULg et al

Conference (2003)

Chalk is the constituent material of numerous oil reservoirs in North Sea. The mechanical behaviour of a saturated chalk has been largely studied. However, different aspects of its behaviour are not yet ... [more ▼]

Chalk is the constituent material of numerous oil reservoirs in North Sea. The mechanical behaviour of a saturated chalk has been largely studied. However, different aspects of its behaviour are not yet well understood: material characteristics depend on the saturating fluids and chalk response is time-dependent. This paper proposes the PASACHALK numerical model: an elasto-plastic constitutive law is presented, which reproduces the different plastic mechanisms of the chalk (pore collapse and shear failure) and the influence of pore fluids. The water sensitivity of this soft rock is explained by the existence of suction effects in chalk. Finally, a simulation of a hypothetical reservoir is proposed to show the response of the elasto-plastic model during depletion phase and water injection phase. [less ▲]

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See detailHigh level Vibration Facility at cryogenic temperature
Grodent, Christophe ULg

Conference (2003)

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See detailA stepwise approach for chemical risks assessment at the workplace
Mairiaux, Philippe ULg; Balsat, Alain; Dujardin, Marc ULg et al

in Strasser, H.; Kluth, K.; Rausch, H. (Eds.) et al Quality of work and products in enterprises of the future (2003)

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See detailHarmonisation des démarches de validation, est-elle possible ?
Hubert, Philippe ULg; Chiap, Patrice ULg; Laurentie, M. et al

Conference (2003)

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See detailOptimization methods for parameter identification of constitutive models in finite viscoplasticity and damage
Stainier, Laurent ULg; KLEINERMANN, J.-P.; Ponthot, Jean-Philippe ULg

in Proceedings of PLASTICITY 2003 (2003)

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See detailThymic IGF-2 and central self-tolerance of the insulin family: a basis for the development of a negative vaccine against type 1 diabetes
Geenen, Vincent ULg; Brilot, Fabienne; Hansenne, Isabelle et al

in Diabetologia (2003), 46 (Suppl. 2)

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See detailTrace metals in the harbour porpoise from the North Sea and adjacent areas: relationship with stable isotope measurements, the nutritional status, lesions of the respiratory system and parasitism.
Das, Krishna ULg; Siebert, Ursula; Fontaine, Michaël et al

Conference (2003)

Growing concern has been raised about the status and the long-term viability of the harbour porpoise (Phocoena phocoena) in the North Sea and adjacent areas. Sources of trace metal variations were ... [more ▼]

Growing concern has been raised about the status and the long-term viability of the harbour porpoise (Phocoena phocoena) in the North Sea and adjacent areas. Sources of trace metal variations were investigated using a multidisciplinary approach. Porpoises from the Belgian coasts were compared to individuals from the German North Sea and Baltic coasts, Denmark, Norway and Iceland. Toxicological results (Hg, Zn, Cu, Cd and Se) were confronted to most common pathological findings, namely emaciation, lesions of the respiratory system or parasitism. Influence of diet through stable carbon and nitrogen analysis (d13C and d15N), age and sex have also been considered. As expected, the nutritional status of stranded harbour porpoise from the Southern North Sea is poor compared to by-caught individuals from Norway and Iceland, as reflected by their blubber thickness, weight to length ratio and hepatic to total body mass ratio. The porpoises collected along the Southern North Sea coast display higher Zn and Hg concentrations compared to individuals collected in more preserved areas from the North Atlantic. Moreover, significant Zn, Hg and Se levels were observed with increasing emaciation severity. Porpoises displaying severe bronchopneumonia also have higher Zn concentrations probably due to the association previously described of emaciation and bronchopneumonia. Hg is clearly linked to parasitism. These increasing concentrations are not related to a shrinking of liver mass as it remains unchanged during the emaciation. As a result, hepatic trace metal load increases also. These observations tend to indicate a general redistribution of heavy metals within the organs (muscles to livers), which results from protein catabolism. Such a re-distribution could well be an additional stress for porpoises already experiencing stressful conditions (organochlorines, etc…). In contrast, Cu and Cd were never associated to emaciation. Other parameters such as age class or diet are more likely to be involved. [less ▲]

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See detailConvection de Bénard-Marangoni en régime oscillant
Dondlinger, Mireille; Dauby, Pierre ULg

in Proceedings du 16ème Congrès français de mécanique, Nice, 1-5 septembre 2003 (2003)

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See detailStability analysis of Bénard-Marangoni convection in the case of cooling from below
Dondlinger, Mireille; Dauby, Pierre ULg

in Proceedings du 6ème Congrès National de Mécanique théorique et appliquée (NCTAM-2003), Gent (Belgium), 26-27 may 2003 (2003)

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See detailSmall mafic intrusions as indicators of downslope draining of dense residual liquids in anorthositic diapirs
Vander Auwera, Jacqueline ULg; Ernst, Gérald; Weis, Dominique et al

in Geophysical Research Abstracts (2003), 5

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See detailValidating structural models in non-linear dynamics
Kerschen, Gaëtan ULg; Golinval, Jean-Claude ULg

in 6ème congrès national de Mécanique Th. et App., Gent, 2003 (2003)

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See detailKarsts en roches non carbonatées - l'exemple des quartzites et des itabérites de Minas Gerais, Brésil
Willems, Luc ULg; Rodet, Joël; Auler, Augusto et al

in Rodet, Joël (Ed.) Actes des Journées Européennes de l'AFK 2003 (2003)

The state of Minas Gérais, Brazil, contains numerous karsts booth inside carbonated and non carbonated rocks. Différent caves are found in quartzite and Itaberite formations (Banded Iron formation). The ... [more ▼]

The state of Minas Gérais, Brazil, contains numerous karsts booth inside carbonated and non carbonated rocks. Différent caves are found in quartzite and Itaberite formations (Banded Iron formation). The term karst is used in the meaning of "any features of the classical karst morphology (caves, sink-holes, lapies...) where dissolution plays the main genetically action and this in any kind of rocks". In some areas, lapiaz and kamenitza affect wide landscapes (area of Diamantina, Natural Parc of Rio Preto). Several caves are found and some of these are several kilomeetres long (grutta do Bromelias, Natural Parc of Ibitipoca). Inside caves, we found numerous forms like dissolution alveoli, spelothems, .... Many times, the cave sides and solutional forms are covered by crust which solidify a very crumbly quartzite. Différent morphologies show an primary solutional stage of the rocks before a physical erosional stage which destroy the earliest forms (piping, river érosion, collapsing). [less ▲]

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See detailNew ruthenium catalysts bearing N-heterocyclic carbene ligands in Kharasch chemistry
Tudose, Adriana; Delfosse, Sébastien; Richel, Aurore ULg et al

Poster (2003)

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See detailAuto-associative neural networks, Part II: Feacture extraction for non-linear model updating
Kerschen, Gaëtan ULg; Golinval, Jean-Claude ULg

in 8th Internationale Conference on Recent Advances in Structural Dynamics, Southampton, 2003 (2003)

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See detailPerfluorooctane sulfonic acids (PFOs) in marine mammals stranded along the North Sea coast.
Van de Vijver, K. I.; Das, Krishna ULg; Van Dongen, W. et al

Poster (2003)

Over the last decades little work has been conducted on the environmental behaviour and effects of perfluorinated organochemicals (FOCs). These chemicals are commonly used as solvents, surfactants ... [more ▼]

Over the last decades little work has been conducted on the environmental behaviour and effects of perfluorinated organochemicals (FOCs). These chemicals are commonly used as solvents, surfactants, cosmetics and are applied in fire foam extinguishers. Recent findings have shown that FOCs (with perfluorooctane sulfonic acid - PFOS - as the most important representative) are detected in organisms living in industrialized as well as in remote areas. The fact that PFOS is hardly biodegradable, clearly accumulates in the liver and blood of top predators and the fact that little information is available on the toxic properties of PFOS, makes this chemical an environmental pollutant of primary concern. In the present study we measured PFOS concentrations in seven marine mammals stranded on the Belgian, French and Dutch North Sea coast between 1994 and 2000. PFOS concentrations were measured in liver and kidney tissue using combined liquid chromatography-mass spectrometry (LC-MS/MS). Detectable PFOS concentrations (up to 820.60 ng/g) were found in harbour porpoises, white-beaked, white-sided and striped dolphins, sperm whales and harbour seals. In fin whale and hooded seal concentrations were below the detection limit of 10 ng/g. PFOS levels in female porpoise livers were significant higher than those in males. The present results show clearly the difference in accumulation pattern of PFOS compared to that of persistent organochlorine chemicals. In order to evaluate the interspecies differences, we developed PFOS-trophic level relationships based on stable nitrogen and carbon isotope ratios. Animals that display the highest trophic positions (highest d15N) have the highest PFOS levels. The different feeding ecology of these species (inshore versus offshore) also seems to contribute to differences in PFOS concentrations. Next to the presentation of PFOS concentrations in marine mammals of the North Sea, the possible toxicological effects of perfluorinated compounds are discussed. [less ▲]

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See detailReal-time ultrasound measurements in fattening bulls from three different breeds
Delobel, A.; Cabaraux, Jean-François ULg; Hornick, Jean-Luc ULg et al

in Book of absracts of the 54th Annual Meeting of the European Association for Animal Production (2003)

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See detailIncreased dioxin/PCB body burden in diabetics: findings in a population-based study in Belgium
Fierens, S.; Mairesse, H.; Heilier, H. et al

in Organohalogen Compounds (2003), 60-65

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See detailSTAT5 promotes granulocyte survival during inflammation
Fievez, Laurence ULg; Desmet, Christophe ULg; Pajak, B. et al

Poster (2003)

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See detailDiversity and complexity of Early Eukaryotic cells
Javaux, Emmanuelle ULg; Knoll, A. H.; Walter, M.

Conference (2003)

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See detailQu'il est long le chemin vers l'équité...
Lafontaine, Dominique ULg

in L'école, dans quel(s) sens ? Actes du 2e Congrès des chercheurs en éducation, Louvain-la-Neuve, 12-13 mars 2002 (2003)

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See detailLa sous-traitance: développements récents
Kohl, Benoît ULg

in Vanwijck, Michèle (Ed.) Contrat d'entreprise et droit de la construction (2003)

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See detailRéflexions sur l'anthropologie du temps: Le cas de l'Egypte ancienne. Questions et méthodes
Winand, Jean ULg

in Pirenne, Vinciane (Ed.) Représentations du temps dans les religions (2003)

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See detailMise en place d’une Sélection Assistée par Marqueurs dans les trois principales races bovines laitières françaises
Fritz, S.; Colleau, J. J.; Druet, Tom ULg et al

in Renc. Rech. Ruminants, 2003, 10 (2003)

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See detailThe mazer physics
Bastin, Thierry ULg

Conference (2003)

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See detailFast, sensitive, and comprehensive analytical methods including three-dimensional analysis (GCXGC-TOFMS) for measuring halogenated persistent organic pollutants
Patterson, Donald G.; Turner, Wayman E.; Sjödin, Andreas et al

in Organohalogen Compounds (2003), 60-65

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See detailDevelopments in finite element simulations of continuous casting
Castagne, S.; Pascon, Frédéric ULg; Bles, G. et al

in Proceedings of the 2nd International Conference on Thermal Process Modelling and Computer Simulations (ICTPMCS) (2003)

Two complementary approaches of steel continuous casting modelling using the finite element code LAGAMINE have been developed in the M&S Department. We propose here a description of the context in which ... [more ▼]

Two complementary approaches of steel continuous casting modelling using the finite element code LAGAMINE have been developed in the M&S Department. We propose here a description of the context in which the study started, then a description of both macroscopic and mesoscopic approaches. The first one describes the whole continuous casting process, from the free surface in the mould and through the entire machine, including thermal and mechanical behaviour of the steel. The second approach focuses on the prediction of cracks and is developed at the grain scale. Some results are also presented for both models. [less ▲]

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See detailL'Europe gravettienne
Otte, Marcel ULg; Noiret, Pierre ULg

in Desbrosse, René; Thévenin, André (Eds.) Préhistoire de l'Europe. Des origines à l'âge du Bronze (2003)

The Gravettian tradition appears to develop from local Mousterian and different cultures at the beginning of the European Upper Palaeolithic (Chatelperronian in the west, foliate points in the north and ... [more ▼]

The Gravettian tradition appears to develop from local Mousterian and different cultures at the beginning of the European Upper Palaeolithic (Chatelperronian in the west, foliate points in the north and the Streletskaian in the east). New technological characteristics proper to the Gravettian developed in different regions of middle Europe, apparently around the same time: thin, standardised blades, development of small backed armatures. The Gravettian is thus a pan-European phenomenon, extending across middle Europe, but developing locally. Development within the Gravettian is quite complex, with regional areas of expansion of processes varying according to the phase or facies considered. The Moldavian sequence is key to understanding the regional development of the Gravettian. It can be integrated with that of central and eastern Europe. General developmental tendencies appeared here, connecting regional patterns with traditional roots. The Gravettian culture can thus be considered a collection of technological processes probably adopted by diverse ethnic groups which nevertheless were in regular contact. During the Second Pleniglacial, important climatic changes provoked a division between central and western groups, leading to profound differences between south-eastern Europe (Ukraine, the Carpathian region, the Balkans) and western Europe (Solutrean-Magdalenian succession). [less ▲]

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See detailWhole-body FDG PET in the follow-up of pediatric patients with lymphoma.
DE BARSY; DEPAS, G.; DRESSE, MF. et al

in Journal of Nuclear Medicine (The) (2003), 44

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See detailOSEM reconstruction of pinhole SPECT acquired in body contour mode.
Seret, Alain ULg; Flérès, D.; Defrise, Michel

Poster (2003)

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See detailOndelettes et télédétection.
Charles, Catherine ULg

in Actes des XXXVèmes Journées de Statistiques (2003)

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See detailL'opération RESSAC : diagnostic métacognitif avant la période de 'bloque'
Leclercq, Dieudonné ULg; Detroz, Pascal ULg; Dupont, Chantal ULg et al

in Actes du 16ème colloque international de l'ADMEE-Europe, 4-6 septembre 2003 (2003)

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See detailIntoxications aiguës au méthanol et à l'éthylène glycol
Charlier, Corinne ULg

Conference (2003)

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See detailSeismic performance of ductile steel moment resisting frames designed according to Eurocode 3 and Eurocode 8. First step for Eurocode 8 calibration.
Sanchez, L.; Plumier, André ULg

in Proceedings of the STESSA 2003 Conference (2003)

The paper discusses the components of reduction factor to be accounted for design purposes. A parametric study of moment resisting steel frames (MRSF) designed according Eurocode 3 (EC3) and Eurocode 8 ... [more ▼]

The paper discusses the components of reduction factor to be accounted for design purposes. A parametric study of moment resisting steel frames (MRSF) designed according Eurocode 3 (EC3) and Eurocode 8 (EC8) is performed. The structural supply of the designed structures exceeds largely the seismic demand in spite of the fact that Ultimate Limit State (ULS) verification of EC8 for MRSF is not conservative. The structural performance is poorly correlated with ULS verification of EC8 but with others code restrains and with parameters like base shear ratio or fundamental period. The practice that deduces the values of reduction factor on the observation of structural performance under past earthquake is not rationally based. This practice tends to make useless the ULS verification for structural systems like MRSF, in which structural performance is poorly correlated with the ULS verification. This practice is responsible of the unsafe values of reduction factors assigned in the seismic codes. [less ▲]

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See detailAtom Transfer Radical Polymerisation (ATRP) and Kharasch addition mediated by titanium-ruthenium bimetallic systems
Richel, Aurore ULg; Delfosse, Sébastien; Demonceau, Albert ULg et al

Poster (2003)

Numerous studies have been directed towards the synthesis of early-late heterobimetallic complexes. Surprisingly, only few reports have been reported about their catalytic behaviour. However, their ... [more ▼]

Numerous studies have been directed towards the synthesis of early-late heterobimetallic complexes. Surprisingly, only few reports have been reported about their catalytic behaviour. However, their potential in homogeneous catalysis is enormous. Indeed, a co-operative work by the two metal centres in the complex may lead to new catalytic systems with unique reactivity. The Dijon’s team has concentrated their efforts on the synthesis and study of heterobimetallic complexes in which both metal fragments are known for their catalytic activity. Titanocenes are of considerable interest as catalysts for the polymerisation of a-olefins. The catalytic performance of RuCl2(arene) complexes (1) has been demonstrated in different reactions, including olefin metathesis and atom transfer radical polymerisation (ATRP). In attempts to examine such type of catalytic systems, complexation of bent titanocene metallo-ligands by the [RuCl2(p-cymene)]2 dimer is currently investigated. [less ▲]

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See detailThe crystal chemistry of lithium in the alluaudite structure
Hatert, Frédéric ULg

Conference (2003)

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See detailClinching joining system: validation of numerical models
Pietrapertosa, C.; Zhang, Lihong ULg; Habraken, Anne ULg et al

in Brucato, V. (Ed.) Proceedings of the 6th International ESAFORM Conference on Material Forming (2003)

The clinching process, also known as “press joining”, is a mechanical joining technique for sheet metal. Its basic principle is to clamp together several metal sheets by an impact extrusion between a ... [more ▼]

The clinching process, also known as “press joining”, is a mechanical joining technique for sheet metal. Its basic principle is to clamp together several metal sheets by an impact extrusion between a punch and a die. The joint is formed by a localized cold plastic deformation. Forming is used as a joining method. Within the context of this research, University of Liège is developing numerical models, with the FEM code LAGAMINE, that simulate the clinching process. On the other hand, shear tests on simple joints with one or two clinches were realized and their behaviour is reproduced numerically with LAGAMINE. This work opens the way to the analytical formulation of the behaviour of clinched joints. The article will focus on comparisons between experiments and numerical simulations. First, the identification of model parameters will be explained. Then, the predicted failure modes will be analysed by comparison with the xperiments. [less ▲]

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See detailEvolution of pressure distribution during apple compression tests measured with tactile sensors
Kleynen, Olivier; de la Cierva, Sonia; Destain, Marie-France ULg

in Acta Horticulturae (2003), (604),

The paper analyses the ability of thin-film tactile sensors in providing information during static compression tests of ‘Jonagold’ apples (Malus pumila) of different ripeness stages. Such sensors are able ... [more ▼]

The paper analyses the ability of thin-film tactile sensors in providing information during static compression tests of ‘Jonagold’ apples (Malus pumila) of different ripeness stages. Such sensors are able to measure the contact surface and the interfacial pressure distribution during compression of fruits, this latter being characterised by suitable mathematical parameters. Results of compression tests between two flat steel plates are presented. The differentiated evolution of the pressure distribution according to the fruit maturity is pointed out. Ability of the sensor in evaluating the firmness is also discussed. [less ▲]

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See detailUnequal Lovers at the laboratory. Non-destructive analyses of a sixteenth century Netherlandish painting
Oger, Cécile ULg; Allart, Dominique ULg; Fraiture, Pascale et al

in Townsend, Joyce; Eremin, Katherine; Adriaens, Annemie (Eds.) Conservation Science 2002. Papers from the Conference held in Edinburgh, Scotland 22-24 May 2002 (2003)

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See detailUrban use of VHR images on Bukavu (Democratic Republic of Congo)
Binard, Marc ULg; De Man, J.; Séba, G. et al

in Proceedings of the Second Workshop of the EARSeL Special Interest Group on Remote Sensing for Developing Countries, Bonn, Germany September 18-20, 2002. EARSeL: Paris, France. (2003)

The main purpose of this study was to show potential uses of very high resolution (VHR) image in an urban analysis of Bukavu in the Democratic Republic of Congo. As for many of the Third-World cities ... [more ▼]

The main purpose of this study was to show potential uses of very high resolution (VHR) image in an urban analysis of Bukavu in the Democratic Republic of Congo. As for many of the Third-World cities, Bukavu grew up during the last decades and available topographical information on Bukavu dates back to the middle of the twentieth century. This lack of updated information can be compensated by an appropriate use of VHR images. In this study, IKONOS image recorded on the 14th February 2001 was used. Image registration are highly dependant on accurate Digital Elevation Models (DEM), these last ones are also useful in urban analyses. The range between the minimum and maximum altitudes observed in the image was more than 500 meters. Furthermore, the viewing inclination angle is more than 28 degrees. In this case, orthorectification is mandatory for correcting relief displacements. Nevertheless, the lack of good Ground Control Points (GPS’s) on the old topographic maps and the failure to collect field verification data in Bukavu explains the remaining global 2D RMSE of 10 meters. For easier image interpretation, multispectral (4m) and panchromatic (1m) images were fused together by means of the LMVM algorithm. Depending on the object, the Computer Aided Photo Interpretation (CAPI) uses or does not use the near infrared information (true or false colour composite). For a more detailed interpretation about the city morphology we draped the 1m multispectral fused image over the 1m resolution DEM grid. The Built-up Area Index (BAI) computed on the urban mask obtained by CAPI and classification of the vegetation, was compared with the 1954 situation interpreted from topographic maps. The present city shows higher BAI values and in the same time the centre of the city has clearly shifted southward. Statistical analyses are also done on built-up versus slope data. The lack of good GCP’s and the use of DEM produced inaccurate orthorectification which was not adequate for topographical features extraction. Nevertheless the present extensions of Bukavu built-up areas are more than the double of those observed at the beginning of the last half century. New constructions are located on steeper slopes where landslides are frequents. More features could be extracted from the Ikonos image if good GPS measurements were made and if verification by the city authorities was possible. Some practical applications of this study could involve determining better location of new Bukavu extensions. [less ▲]

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See detailDischarge management for frail geriatric patients : effects of an implementation project
Milissen, K; Steeman, E; Moons, P et al

Conference (2003)

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See detailUtilisation des techniques végétales pour la stabilisation des berges : suivi de chantiers réalisés dans différents types de rivières wallonnes.
Hallot, Eric ULg; Petit, François ULg; Verniers, G. et al

in Evaluer le milieu - Journées des géographes belges (2003)

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See detailStudy of a method of scale reduction to test sign legibility in fog.
Dore, J.; Colomb, M.; Cavallo, V. et al

Conference (2003)

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See detailExternal quality grading of Jonagold apples using a multi-spectral vision system
Kleynen, Olivier; Leemans, Vincent ULg; Destain, Marie-France ULg

in Balsa-Canto E., Mora J.; Onate E. (Eds.) II International Workshop - Information Technologies and Computing Techniques for the Agro-Food Sector (2003)

This paper presents a method to sort Jonagold apples using a four bands multi-spectral image acquisition device. Multi-spectral images of sound tissue and various defects were acquired. Defects could be ... [more ▼]

This paper presents a method to sort Jonagold apples using a four bands multi-spectral image acquisition device. Multi-spectral images of sound tissue and various defects were acquired. Defects could be divided into four classes: slight defects (e.g. small russet), more serious defects (scar tissue), defects leading to the rejection of the fruit (e.g. rot) and recent bruises (between one hour and two hours old). Image segmentation was based on the Bayes' theorem. Each pixel of the fruit was classified into 'healthy' or 'defect' classes according to the probability distribution of the spectral components of each class. Once segmented, the fruit was graded by linear discriminant analysis on the basis of the relative area of the defect and statistical parameters computed on the spectral components of the two tissues classes. Results (cross validation) showed 94% and 84% if the sound and defective fruits respectively well classified. Most of the misclassified defective fruits (89%) belonged to the slight defect category. [less ▲]

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See detailElectromagnetic waves in periodic structures
Guenneau, S.; Nicolet, A.; Geuzaine, Christophe ULg et al

in Proceedings of the Eleventh International Symposium on Applied Electromagnetics and Mechanics, ISEM 2003 (2003)

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See detailBehavioral characterization of acetaldehyde in C57BL/6J mice: Anxiolytic, amnesic and hedonic effects
Tambour, Sophie ULg; Quertemont, Etienne ULg; Tirelli, Ezio ULg

in Behavioural Pharmacology (2003), 14(Suppl. 1), 68-69

It has been postulated that a number of central effects of ethanol are mediated through the action of its first metabolite, acetaldehyde. In particular, acetaldehyde might be involved in the anxiolytic ... [more ▼]

It has been postulated that a number of central effects of ethanol are mediated through the action of its first metabolite, acetaldehyde. In particular, acetaldehyde might be involved in the anxiolytic and hedonic effects of ethanol and is therefore believed to play an important role in alcohol abuse. In agreement with this assumption, previous studies indicated that acetaldehyde is mainly reinforcing in rats, which have been shown to readily self-administer acetaldehyde both peripherally and centrally. However, the hedonic effects of acetaldehyde have never been tested in mice, and the possible amnesic and anxiolytic effects of acetaldehyde remain to be elucidated. Therefore, the present studies were aimed at characterizing the anxiolytic, hedonic and amnesic effects of acetaldehyde after its acute peripheral administration to C57BL/6J mice. The effects of intraperitoneal acetaldehyde (0-300 mg/kg) injections were assessed in several classical behavioral tests. The anxiolytic effects were tested with the elevated plus maze, the hedonic effects with the place conditioning procedure and the amnesic effects with the passive avoidance apparatus. Our results show that acetaldehyde dose-dependently altered memory consolidation as evidenced by a reduced performance in the passive avoidance test when acetaldehyde was injected immediately after training at doses between 100 and 300 mg/kg. The elevated plus-maze showed that acetaldehyde, in contrast to ethanol, does not possess anxiolytic properties. Finally, the results of the place conditioning experiment confirmed that acetaldehyde displays significant hedonic properties. The present results add further support to the role of acetaldehyde in ethanol amnesic and hedonic effects but interestingly suggest that acetaldehyde is not involved in ethanol anxiolytic effects. [less ▲]

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See detailA general recurrence relation between the moments of a scaling function
Bastin, Françoise ULg; Nicolay, Samuel ULg

in Group 24 : Physical And Mathematical Aspects Of Symmetries (2003), 173

Under natural and weak hypotheses, we prove a reproducing formula for polynomials. Then we obtain a new recurrence relation between the moments of a scaling function and a new exact formula for the ... [more ▼]

Under natural and weak hypotheses, we prove a reproducing formula for polynomials. Then we obtain a new recurrence relation between the moments of a scaling function and a new exact formula for the computation of moments of even order. [less ▲]

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See detailBehavioral characterization of acetaldehyde in C57BL/6J mice: Locomotor, hypnotic and ataxic effects
Quertemont, Etienne ULg; Tambour, Sophie ULg; Tirelli, Ezio ULg

in Behavioural Pharmacology (2003), 14(Suppl. 1), 69-69

Acetaldehyde, the first ethanol metabolite, was recently suggested to play a major role in many behavioral effects of ethanol. However, no studies have directly investigated the behavioral effects of ... [more ▼]

Acetaldehyde, the first ethanol metabolite, was recently suggested to play a major role in many behavioral effects of ethanol. However, no studies have directly investigated the behavioral effects of acetaldehyde after acute administration. Therefore, the aim of the present study was to characterize the locomotor, hypnotic and ataxic effects of acetaldehyde in C57BL/6J mice. Various acetaldehyde doses (0-300 mg/kg) were injected intraperitoneally and their effects were investigated with several classical behavioral tests. The locomotor effects of acetaldehyde were measured in standard activity boxes. In addition, the loss of righting reflex was used to assess the hypnotic effects of acetaldehyde. Finally, the ataxic effects of acetaldehyde were studied with the horizontal wire test. The results show that acetaldehyde induced a significant hypolocomotor effect at 170 mg/kg and higher doses. In addition, the hypnotic effects of acetaldehyde were evidenced by a loss of righting reflex in doses between 170 and 300 mg/kg. However, the locomotor and hypnotic effects of acetaldehyde were very brief relative to what is observed after ethanol administration. After 170 mg/kg acetaldehyde, normal activity was recovered in less than 30 minutes and the loss of righting reflex lasted only an average of 6.14 ± 1.29 minutes after the administration of 300 mg/kg acetaldehyde, the highest testable dose before lethality. Ataxic effects were observed with lower doses that did not significantly affect locomotor activity. These results show that acetaldehyde, like ethanol, possesses sedative, hypnotic and ataxic properties and therefore indicate that the first product of ethanol metabolism might be involved in these ethanol effects. [less ▲]

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See detailPreparation and characterization of xerogel catalyst microspheres
Alié, Christelle ULg; Ferauche, Fabrice; Heinrichs, Benoît ULg et al

Conference (2003)

For easier handling and use in fixed bed reactors, Pd-Ag/SiO2 aerogel-like xerogel catalysts were shaped into microspheres using the microencapsulation process developed by BRACE GmbH. Before the bead ... [more ▼]

For easier handling and use in fixed bed reactors, Pd-Ag/SiO2 aerogel-like xerogel catalysts were shaped into microspheres using the microencapsulation process developed by BRACE GmbH. Before the bead production process, the xerogel catalyst was ground in water and mixed with ethylene glycol and sodium alginate, the latter of which is the gelation agent. The beads were formed at a vibrating nozzle and solidified during their fall in a water tank containing calcium ions, which induce cross-linking of the alginate and consequent bead hardening. Preliminary work was done using a syringe instead of the material-consuming BRACE unit. The beads were made from a suspension of dried only, dried and calcined, or dried, calcined, and reduced catalyst. The textural properties of the beads were analyzed by nitrogen adsorption-desorption isotherms and mercury porosimetry; and bead catalytic activity was tested for selective hydrodechlorination of 1,2-dichloroethane. The beads made from a suspension of dried catalyst appear to have properties the closest to that of the xerogel reference catalyst. Porosity and surface area are maintained at their level before bead formation. However conversion of 1,2-dichloroethane decreases after the production process, possibly due to poisoning by calcium ions. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailL'efficacité au prix de l'hétérogénéité : une approche comparative
Lafontaine, Dominique ULg

in Actes du colloque organisé par le Conseil de l'Education et de la Formation (2003)

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See detailSpectroscopic characterisation of Pd/SiO2 sol-gel prepared catalysts
Beketov, Gennadiy; Heinrichs, Benoît ULg; Lambert, Stéphanie ULg et al

Poster (2003)

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See detailQuelle place accorder aux différentes dimensions de la discipline ? Questions et prise de position d’un géomorphologue
Petit, François ULg

in Quelle géographie enseigner demain à l'Université ? (2003)

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See detailCombinaison de la radiographie et de l'échographie pour l'examen du grasset sur le terrain
Busoni, Valeria ULg

in Proceedings de la Journée de la Belgian Equine Practitioners Society (BEPS) (2003)

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See detailFattening of young bulls: comparaison of three breeds and two managements
Cabaraux, Jean-François ULg; Hornick, Jean-Luc ULg; Istasse, Louis ULg et al

in Book of absracts of the 54th Annual Meeting of the European Association for Animal Production (2003)

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See detailNumerical investigation of photonic crystal fibers by spectral and multipole methods
Nicolet, A.; Guenneau, S.; Zolla, F. et al

in Asymptotics, Singularities and Homogenisation in Problems of Mechanics, Proceedings of the IUTAM Symposium (Liverpool, July 2002) (2003)

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See detailEtude rétrospective des causes médicales d’intolérance à l’effort chez 345 chevaux
Ponthier, Jérôme ULg; Van Erck, Emmanuelle; Art, Tatiana ULg et al

in Proceedings du Congrès de l'Association Vétérinaire Equine Française (AVEF) (2003)

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See detailInfluence de la substitution du tourteau de soja par des graines de lupin, avec ou sans complément d'alpha-galactosidase, sur la digestibilité des régimes et la rétention azotée du porc en croissance
Froidmont, Eric; Schoeling, Olivia; Deliège, Françoise et al

in Journées Recherche Porcine (2003)

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See detailUn nouveau schéma d'intégration conservatif pour des modèles constitutifs hypoélastiques irréversibles.
Noels, Ludovic ULg; Stainier, Laurent ULg; Ponthot, Jean-Philippe ULg

in Potier-Ferry, M.; Bonnet, M.; Bignonnet, A. (Eds.) Actes du Sixième Colloque National en Calcul des Structures (2003)

Ce travail propose une nouvelle évaluation des forces internes pour les modèles constitutifs hypoélastiques irréversibles dans le cadre de la méthode des éléments-finis en grandes transformations. Nous ... [more ▼]

Ce travail propose une nouvelle évaluation des forces internes pour les modèles constitutifs hypoélastiques irréversibles dans le cadre de la méthode des éléments-finis en grandes transformations. Nous démontrons que cette expression des forces internes utilisée avec un schéma d'intégration du point milieu conduit à un algorithme d'intégration consistant avec les lois de la thermodynamique. [less ▲]

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See detailA new formulation of internal forces for non-linear hypoelastic constitutive models verifying conservation laws
Noels, Ludovic ULg; Stainier, Laurent ULg; Ponthot, Jean-Philippe ULg et al

in Bathe, K. J. (Ed.) Second MIT Conference on Fluid and Solid Mechanics (2003)

This paper proposes a new formulation of the internal forces for hypoelastic constitutive models ensuring that the elastic work of deformation can be restored by the scheme. Moreover, we demonstrate that ... [more ▼]

This paper proposes a new formulation of the internal forces for hypoelastic constitutive models ensuring that the elastic work of deformation can be restored by the scheme. Moreover, we demonstrate that the work of the plastic deformation is positive and consistent with the material model. [less ▲]

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See detailNew algorithm concept for a model of mixed lubrication in cold rolling
STEPHANY, A.; Ponthot, Jean-Philippe ULg; COLLETTE, C. et al

in Proceedings of METEC 2003, European Rolling Conference (2003)

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See detailPhotometric Mode Identification in the Two Doradus Stars HD 12901 and HD 48501
Aerts, C.; Cuypers, J.; Dupret, Marc-Antoine ULg et al

in Asteroseismology Across the HR Diagram (2003)

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See detailDioxins, furans and co-planar PCBs in juvenile harbour porpoises (Phocoena phocoena) from the Belgian coasts
Beans, Cristina ULg; Das, Krishna ULg; Jauniaux, Thierry ULg et al

Poster (2003)

Dioxins, furans and PCBs are lipophilic anthropogenic contaminants that have found their way into marine food webs and accumulate in top predators such as marine mammals, adding a stress factor to an ... [more ▼]

Dioxins, furans and PCBs are lipophilic anthropogenic contaminants that have found their way into marine food webs and accumulate in top predators such as marine mammals, adding a stress factor to an already vulnerable population. In this study 7 congeners of dioxins (PCDDs), 10 congeners of furans (PCDFs) and 4 congeners of coplanar PCBs (cPCBs) were determined using high resolution gas chromatography and mass spectrometry in the blubber of 19 juvenile harbour porpoises (Phocoena phocoena) stranded along the Belgian North Sea coastline between 1995 and 2001. These results were contrasted with nutritional status (emaciated or not), sex and trophic level (through stable carbon and nitrogen isotope analysis). Mean blubber concentrations of SPCDD/Fs were 12.8 pg/g lw (lipid weight) and mean related toxicity 1.84 pg TEQs/g lw (TEQs = TCDD toxic equivalents). Mean cPCB concentrations were 223,5 pg/g lw and mean related toxicity 4,47 pg TEQs/g lw. The levels detected in these individuals were of the same order as those found in a previous study in the Wadden Sea (Bruhn, 1999). Both sexes show rather similar levels. No significant relationship was observed between stable carbon or nitrogen isotope values and pollutant levels. Concentrations and toxicity show a tendency to be higher in emaciated ndividuals than in nonemaciated ones. This could indicate a possible relationship between the nutritional status of the animals and dioxinlike pollutants (which could participate in weakening the animal). This situation should be further studied on adult individuals in order to obtain a more global view of the possible effects on the population. [less ▲]

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See detailFaire mentir les prédictions en 1ère candidature : comment ? Avec quel résultat ? L'opération RESSAC (Résultats d'Epreuves Standardisées au Service de l'Apprentissage en Candis)
Leclercq, Dieudonné ULg; Dupont, Chantal ULg; Detroz, Pascal ULg et al

in L'école, dans quel(s) sens ? Actes du 2e congrès des chercheurs en éducation, Louvain-la-Neuve, 12-13 mars 2002 (2003)

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See detailNumerical - experimental interaction in hydrodynamics: an integrated approach for the optimal management of hydraulic structures and hydrographic basins
Pirotton, Michel ULg; Lejeune, André ULg; Archambeau, Pierre ULg et al

in Lu; Lamas; Li (Eds.) et al Computational Methods in Engineering and Science (2003)

The present paper presents studies and tools devoted to the reduction of uncertain-ties in the scientific knowledge of various unsteady flows, including solid transport effects, in the perspective of ... [more ▼]

The present paper presents studies and tools devoted to the reduction of uncertain-ties in the scientific knowledge of various unsteady flows, including solid transport effects, in the perspective of applications such as restoration, rehabilitation and enhancement of riverbeds, rivers and waterways. This global approach will be tested and fitted in a dynamic and integrated experimental model of reference flows in the laboratory. The relevance of using of physical experimental scale models will be highlighted for the identification of constitutive laws used in numerical modelling. Practical applications prove that the integration of powerful hydrodynamic software for water management is realistic and will lead to compute transient flooding, sedimentation and erosion events in natural compound channels, as well as to design and simulate the behaviour of hydraulic regulation works or locks. It will also help in working out new projects or reconstructions of hydraulic infrastructures, as well as ecological rehabilitations. Even if the sole quantitative plan will be taken into account, this opti-misation project will also lead to highlight favourable solutions, from a qualitative point of view. [less ▲]

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See detailDecidability of invariant validation for paramaterized systems
Fontaine, Pascal; Gribomont, Pascal ULg

in Lecture Notes in Computer Science (2003), 2619

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See detailLe japonisme en Belgique à la fin du XIXe siècle. Le cas d’Armand Rassenfosse
Bawin, Julie ULg

in 6e congrès de l’Association des cercles francophones d’histoire et d’archéologie de Belgique, LIIIe congrès de la fédération des cercles d’archéologie et d’histoire de Belgique (2003)

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See detailIsokinetic profile of javelin throwers and relationship to field tests
Forthomme, Bénédicte ULg; Croisier, Jean-Louis ULg; Forthomme, L. et al

in Vlaams Tijdschrift voor Sport Geneeskunde & Sport Wetenschappen (2003), 95

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See detailVerbes centraux du dispositif des chartes médiévales : essai d'analyse
Boutier, Marie-Guy ULg

in Sánchez Miret, Fernando (Ed.) Actas del XXIII Congreso internacional de lingüística y filología románica (2003)

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See detailModeling Stationary and Evolving Discontinuities with Finite Elements
Moës, Nicolas; Béchet, Eric ULg

in Owen, D. R. J.; Onate, E. (Eds.) VII International Conference on Computational Plasticity COMPLAS 2003 (2003)

A methodology for treating non-planar three-dimensional cracks with geometries that are independent of the mesh is summarized. The method is based on the extended finite element method, in which the crack ... [more ▼]

A methodology for treating non-planar three-dimensional cracks with geometries that are independent of the mesh is summarized. The method is based on the extended finite element method, in which the crack discontinuity is introduced as a Heaviside step function via a partition of unity. In addition, branch functions are introduced for all elements containing the crack front. The crack geometry is described by two signed distance functions (level sets), which in turn can be defined by nodal values. Consequently, no explicit representation of the crack is needed. A Hamilton-Jacobi equation is used to update the level sets as the crack grows. Numerical experiments show the robustness of the method in treating cracks with significant changes in topology. The method is readily extendable to inelastic fracture problems. [less ▲]

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See detailNouveau concept algorithmique pour un modèle de laminage à froid en régime mixte
STEPHANY, A.; Ponthot, Jean-Philippe ULg; COLLETTE, C. et al

in Proceedings of the 6ème colloque national en calcul des structures (2003)

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See detailLevels of selected PBDEs and PCBs in Belgian human milk
Pirard, C.; De Pauw, Edwin ULg; Focant, Jean-François ULg

in Organohalogen Compounds (2003), 61

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See detailPour une histoire de l'affiche
Duchesne, Jean-Patrick ULg

in Actes du colloque Le conservateur et l'affiche (2003)

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See detailCloning and identification of functional domains in quail Brain aromatase
Charlier, Thierry ULg; Baillien, Michelle; Ball, Gregory F. et al

Poster (2003)

Recent evidence indicates that aromatase activity (AA) in the hypothalamus is not only modulated by slow (hours to days) genomic actions but also through fast (seconds to minutes) non-genomic mechanisms ... [more ▼]

Recent evidence indicates that aromatase activity (AA) in the hypothalamus is not only modulated by slow (hours to days) genomic actions but also through fast (seconds to minutes) non-genomic mechanisms. We recently showed that Calcium (Ca2+)-dependent phosphorylations catalyzed by multiple protein kinases including PKC, and possibly PKA and CAMK, rapidly down-regulate AA in quail hypothalamic homogenates. Western blotting experiments also indicated that phosphorylations affect the aromatase molecule itself but it was impossible to fully characterize the putative phosphorylation sites on the quail enzyme because its sequence was unknown. We therefore cloned and sequenced the quail brain aromatase. We identified a 1541-bp open reading frame that encodes a predicted 490-amino acid protein containing all functional domains previously described in mammalian and other avian aromatases. Multiple motifs match consensus sequences corresponding to several protein kinases including those that were shown to affect AA during pharmacological experiments with specific kinase inhibitors (e.g., PKC, PKA, MAPK, Myosine light chain kinase, Tyr. kinase). Another potential control pathway of AA, independent from phosphorylations, could involve a direct control by Ca2+-dependent calmodulin (CAM), as suggested by the identification in Western blots of CAM on purified aromatase from quail hypothalamic homogenates. Accordingly, two Ca2+-dependent calmodulin binding motifs (1-8-14b) as defined by Rhoads and Friedberg (FASEB, 1997, 11:331-340) are present and conserved in most vertebrates including quail aromatase. These results suggest that the phosphorylation of some residues as well as the direct binding of calmodulin on the aromatase protein represent part of the mechanism(s) underlying the rapid changes in AA. [less ▲]

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