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See detailIncreased expression of receptor activator of NF-kappa B ligand (RANKL), its receptor RANK and its decoy receptor osteoprotegerin in the colon of Crohn's disease patients
Franchimont, N.; Reenaers, Catherine ULg; Lambert, Chantal ULg et al

in Clinical & Experimental Immunology (2004), 138(3), 491-498

Crohn's disease (CD) is associated with low bone mass due to chronic inflammation and other factors. Receptor activator of NF-kappaB ligand (RANKL), its receptor RANK and its decoy receptor ... [more ▼]

Crohn's disease (CD) is associated with low bone mass due to chronic inflammation and other factors. Receptor activator of NF-kappaB ligand (RANKL), its receptor RANK and its decoy receptor osteoprotegerin (OPG) are potentially involved in this process as they regulate osteoclastogenesis and are influenced by pro-inflammatory cytokines. The aim of this study was to determine the levels of soluble RANKL (sRANKL), RANK and OPG expression both in the serum and in the colon of CD patients. Levels of sRANKL and OPG were assessed in the serum and the supernatants of cultured colonic biopsies in patients with CD and controls by ELISA. RANK expression was explored by immunostaining and immunofluorescence of fixed colonic samples. OPG and sRANKL levels were higher in the serum of CD patients as compared to age- and sex-matched controls. Levels of sRANKL and OPG were significantly enhanced in cultured colonic biopsies from CD, and OPG levels correlated with histological inflammation, and pro- and anti-inflammatory cytokine levels. No significant correlation was found for sRANKL. RANK(+) cells were increased in the colon of CD, particularly in inflamed areas. These cells were positive for CD68 or S100 protein. We conclude that serum and local levels of sRANKL and OPG are increased in CD. Moreover, RANK is expressed in the colonic mucosa by subpopulations of activated macrophages or dendritic cells at higher levels in CD compared to normal colon. [less ▲]

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See detailEffect of transplantation on Posidonia oceanica shoots
Vangeluwe, Denis; Lepoint, Gilles ULg; Bouquegneau, Jean-Marie ULg et al

in Vie et Milieu-Life and Environment (2004), 54(4), 223-230

Posidonia oceanica shoots sampled from the healthy meadow in the bay of Revelatta (Corsica, France) were transplanted on metallic grids at 10 m depth. Transplanted shoots have been regularly monitored by ... [more ▼]

Posidonia oceanica shoots sampled from the healthy meadow in the bay of Revelatta (Corsica, France) were transplanted on metallic grids at 10 m depth. Transplanted shoots have been regularly monitored by the measurement of growth, biomass and C, N and P contents in the leaves and the belowground parts. After six months of experiment, the survival rates varied from 14 to 84 % on the different transplantation sites. Leaf biomass on the transplanted cuttings was lower than biomass in the control shoots but root biomass raised from December 2000 to May 2001 on the transplanted shoots. Transplant growth (8,3 +/- 2,3 mm.d(-1).shoot(-1)) after six months was similar to control growth (8,2 +/- 2,8 mm.d(-1). shoot(-1)). The C, N and P contents in transplants were significatively lower than in control shoots suggesting that transplanted cuttings are unable to meet their nutrient requirements. The modifications of the C, N, P contents in the belowground parts of the transplanted shoots indicate a mobilization of these nutrients in those compartments to produce new roots and restore a normal nutrients absorption. [less ▲]

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See detailL'image du mois. Ulcere perineal chez une patiente atteinte de spina bifida
Lorquet, Sophie ULg; Conti, V.; Nervo, Patricia ULg et al

in Revue Médicale de Liège (2004), 59(12), 688-90

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See detailApprentissage par problèmes, à distance. Présentation et analyse d'un dispositif de formation.
Dury, Cécile ULg

in Recherche en Soins Infirmiers (2004), 79

Cet article présente et analyse un dispositif de formation visant l’acquisition de compétences en soins infirmiers. Les objectifs poursuivis sont le développement: - d’une méthode pédagogique active ... [more ▼]

Cet article présente et analyse un dispositif de formation visant l’acquisition de compétences en soins infirmiers. Les objectifs poursuivis sont le développement: - d’une méthode pédagogique active : l’apprentissage par problèmes (APP) ; - de l’approche interdisciplinaire et interculturelle, les mêmes problèmes étant résolus par des étudiants de différentes disciplines et cultures ; - de l’utilisation des nouvelles technologies de l’information et de la communication (NTIC) afin de permettre une collaboration maximale « à distance » entre les différents partenaires du projet. L’analyse du dispositif montre que les objectifs pédagogiques poursuivis par l’APP sont atteints. L’approche pluridisciplinaire et pluriculturelle, pour être optimale, demande une grande coordination entre les partenaires, un équilibre entre les groupes d’étudiants des différents pays et disciplines, une formation et un soutien des tuteurs dans l’utilisation de la plate-forme d’enseignement à distance. [less ▲]

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See detailCollective Motion: Bistability and Trajectory Tracking
Paley, Derek; Leonard, Naomi; Sepulchre, Rodolphe ULg

in Proceedings of the 43rd IEEE Conference on Decision and Control (2004, December)

This paper presents analysis and application of steering control laws for a network of self-propelled, planar particles. We explore together the two stably controlled group motions, parallel motion and ... [more ▼]

This paper presents analysis and application of steering control laws for a network of self-propelled, planar particles. We explore together the two stably controlled group motions, parallel motion and circular motion, for modeling and design purposes. We show that a previously considered control law simultaneously stabilizes both parallel and circular group motion, leading to bistability and hysteresis. We also present behavior primitives that enable piecewise-linear network trajectory tracking. [less ▲]

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See detailLes travaux de la CPDT comme appui à la mise en oeuvre de la Convention européenne du Paysage en région wallonne
Droeven, Emilie ULg; Kummert, Magali

Conference given outside the academic context (2004)

Dès 2000, la Région wallonne a lancé un programme de recherche au sein de la Conférence Permanente du Développement Territorial (CPDT) pour répondre aux exigences de mise en œuvre de la Convention ... [more ▼]

Dès 2000, la Région wallonne a lancé un programme de recherche au sein de la Conférence Permanente du Développement Territorial (CPDT) pour répondre aux exigences de mise en œuvre de la Convention européenne du paysage. La communication s’attache à retracer le cheminement d’une partie de cette recherche jusqu’en novembre 2004. Toutes les contributions de la CPDT en la matière ne sont pas présentées ici. Dans un premier temps, les travaux se sont concentrés sur l’identification des macro-paysages wallons (carte des territoires paysagers) puis sur la mise au point d’une méthode d’identification des paysages patrimoniaux wallons. [less ▲]

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See detailCharacterization of the tumor micro-environment after administration of glucocorticoids to understand their radiosensitization effect
Crokart; Jordan; Baudelet et al

Poster (2004, November 26)

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See detailMutation douce de l'enseignant en concepteur-tuteur dans des activités d'apprentissage totalement à distance. Communication présentée au Colloque TICE Méditérannée, Nice
Vandeput, Etienne ULg; Denis, Brigitte ULg

in Actes du colloque TICE Méditérannée (en ligne) (2004, November 26)

Experts in education and communication technology cannot speak about distance learning without calling up the new roles it springs up and the new relationships it generates. Its detractors claim that ... [more ▼]

Experts in education and communication technology cannot speak about distance learning without calling up the new roles it springs up and the new relationships it generates. Its detractors claim that, under these new conditions, this kind of learning requires significant and expansive means unlike a more classical one. Instead of giving up in front of such disheartening elements, the authors have been trying to measure how far a simple distance learning system (i.e. with little human, hardware and software means) can be implemented. In that way, they have been creating a learning environment basically based on a mixture of individual and collaborative works. Owing to both this mixture and the organization structure, the students can reach the fixed learning goals. Through these processes, they try to isolate practices, learners or teaching staff should be inspired by. They should, in that way, evolve slightly from a classical context to the design of learning scripts including efficient tutoring in a distance context. The course described in this paper is called “Analysis of distance learning environments”. The public consists of adults having enrolled for a DES in Education and Training Technology. To conduct this experiment, the authors have been setting themselves some rules and constraints in order to derive a general process that might be applied to various situations. These rules and constraints are very close to the usual learner’s working constraints. Recommendations focus on practices including careful preparation, coordination techniques betweenteachers and learner’s initiation into reflexivity. [less ▲]

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See detailSelf-association of double-hydrophilic copolymers of acrylic acid and poly(ethylene oxide) macromonomer
Khousakoun, Eric; Gohy, Jean-François; Jérôme, Robert ULg

in Polymer (2004), 45(25), 8303-8310

Poly(ethylene oxide) (PEO) end-capped by a methacrylate unsaturation was copolymerized with acrylic acid by RAFT with dibenzyltrithiocarbonate as a chain transfer agent. Tapered triblock copolymers ... [more ▼]

Poly(ethylene oxide) (PEO) end-capped by a methacrylate unsaturation was copolymerized with acrylic acid by RAFT with dibenzyltrithiocarbonate as a chain transfer agent. Tapered triblock copolymers consisting of a poly(acrylic acid) (PAA) inner block and comb-like outer blocks of PEO macromomers were formed as result of the comonomers reactivity ratios. Composition of these copolymers and length of the PEO branches were varied. Dynamic light scattering (DLS) was used to characterize the aggregates formed in water and to investigate their response to stimuli, such as pH, temperature and ionic strength. In parallel, the morphology of the aggregates was directly observed by transmission electron microscopy (TEM). Well-defined aggregates were formed in the 5<pH<8 range, with a morphology strongly depending on the copolymer composition. At pH<5, the copolymers were poorly soluble and no well-defined structure was observed, whereas free chains were formed at pH>8 as consequence of the complete ionization of the PAA block. [less ▲]

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See detailLes apports de l'ULg dans le domaine de l'incendie
Franssen, Jean-Marc ULg

Conference given outside the academic context (2004)

In this presentation, the output provided by the University to the community about fire safety are presented. Three subjects are mentionned: teaching, research and consulting services.

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See detailLe syndrome de Parsonage et Turner
Kaux, Jean-François ULg; Wang, François ULg

Conference (2004, November 02)

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See detailThe photospheric abundances of active binaries. III. Abundance peculiarities at high activity levels
Morel, Thierry ULg; Micela, G.; Favata, F. et al

in Astronomy and Astrophysics (2004), 426

We report the determination from high-resolution spectra of the atmospheric parameters and abundances of 13 chemical species (among which lithium) in 8 single-lined active binaries. These data are ... [more ▼]

We report the determination from high-resolution spectra of the atmospheric parameters and abundances of 13 chemical species (among which lithium) in 8 single-lined active binaries. These data are combined with our previous results for 6 other RS CVn systems to examine a possible relationship between the photospheric abundance patterns and the stellar activity level. The stars analyzed are generally found to exhibit peculiar abundance ratios compared to inactive, Galactic disk stars of similar metallicities. We argue that this behaviour is unlikely to be an artefact of errors in the determination of the atmospheric parameters or non-standard mixing processes along the red giant branch, but diagnoses instead the combined action of various physical processes related to activity. The most promising candidates are cool spot groups covering a very substantial fraction of the stellar photosphere or NLTE effects arising from nonthermal excitation. However, we cannot exclude the possibility that more general shortcomings in our understanding of K-type stars (e.g. inadequacies in the atmospheric models) also play a significant role. Lastly, we call attention to the unreliability of the (V-R) and (V-I) colour indices as temperature indicators in chromospherically active stars. Based on observations collected at the European Southern Observatory, Chile (Proposals 64.L-0249 and 071.D-0260). Table A.1 is only 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/cgi-bin/qcat?J/A+A/426/1007 [less ▲]

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See detailPolarization properties of broad absorption line QSOs: New statistical clues
Lamy, H.; Hutsemekers, Damien ULg

in Astronomy and Astrophysics (2004), 427

We report the results of several statistical tests performed on a large sample of 139 broad absorption line (BAL) QSOs with good quality optical spectra and/or optical polarization data. Correlations ... [more ▼]

We report the results of several statistical tests performed on a large sample of 139 broad absorption line (BAL) QSOs with good quality optical spectra and/or optical polarization data. Correlations between ten optical indices and the polarization degree p[SUB]0[/SUB] are systematically searched for. We find six significant non-trivial correlations. In order to identify the most important correlations, we perform a principal component analysis with a sample of 30 BAL QSOs and eight quantities (including p[SUB]0[/SUB]). Most of the variance (Ë 57%) in the data is contained in two principal components called PC1 and PC2. PC1 is mainly dominated by the correlation between the balnicity index BI and the strength of the Fe II emission; it may be driven by the accretion rate of matter onto the central compact object. The variance in PC2 is essentially due to the anti-correlation between p[SUB]0[/SUB] and the detachment index DI, indicating that BAL QSOs with P Cygni profiles (DIâ ª) are usually more polarized than those objects with C IV absorption troughs well detached from the corresponding emission lines (DIâ «). We show that PC2 may be related to the orientation of the BAL QSOs with respect to the line of sight. We also present new spectropolarimetric observations of six BAL QSOs. By adding spectropolarimetric data from the literature, we build a sample of 21 BAL QSOs for which we define four spectropolarimetric indices describing the polarization properties of the absorption and emission lines. We find that the polarization of the C III]] emission line is systematically higher than the polarization of the C IV emission line, and that the highest polarization in the troughs is correlated to the balnicity index. Another important result emerging from the statistical tests performed on this spectropolarimetric sample is a possible anti-correlation between the detachment index and a quantity SI which measures the ratio of the depths of the C IV absorption in the polarized flux and in the total flux. This correlation indicates that in BAL QSOs with P cygni profiles, the BAL troughs in the polarized flux are nearly as deep as in the total flux while, in BAL QSOs with detached absorptions, the BAL troughs in the polarized flux are much weaker than in the total flux. We show that our main results may be explained in the framework of a ``two-component'' wind model which is a natural extension of the classical wind-from-disk models. In this model, the broad absorption occurs in a dense equatorial wind emerging from the accretion disk, while scattering and polarization mainly take place in a polar region. The orientation relative to the observer drives the correlations p[SUB]0[/SUB] - DI and DI - SI. While most of our observations can be explained within this framework, there are also several indications that other polarization mechanisms, and more particularly resonance scattering, may also be at work. Based on observations collected at the European Southern Observatory (ESO, La Silla). Table 1 is only 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/cgi-bin/qcat?J/A+A/427/107 [less ▲]

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See detailL'astronomie dans le monde
Manfroid, Jean ULg

Article for general public (2004)

EF Eridani; Du sucre dans l'espace; Miras à la baisse; Eau et méthane sur Mars; Toutatis à  l'ESO; SMART-1; Pollution globale; L'univers en 3D : symposium Gaia à Paris; Découverte du plus grand champ de ... [more ▼]

EF Eridani; Du sucre dans l'espace; Miras à la baisse; Eau et méthane sur Mars; Toutatis à  l'ESO; SMART-1; Pollution globale; L'univers en 3D : symposium Gaia à Paris; Découverte du plus grand champ de cratères de météorites sur Terre; Cratère mystérieux; Minimum solaire [less ▲]

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See detailBorges traductor: refracciones y tapices de Flandes
Willson, Patricia ULg

Article for general public (2004)

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See detailLong-term outcome of patients with acromegaly and congestive heart failure
Bihan, Hélène; Espinosa, Consuelo; Valdes Socin, Hernan Gonzalo ULg et al

in Journal of Clinical Endocrinology and Metabolism (2004), 89(11), 5308-5313

Cardiovascular complications are a major cause of morbidity and mortality in patients with acromegaly. Normalization of GH secretion is associated with an improvement in structural and functional cardiac ... [more ▼]

Cardiovascular complications are a major cause of morbidity and mortality in patients with acromegaly. Normalization of GH secretion is associated with an improvement in structural and functional cardiac abnormalities. However, the long-term cardiac effects of treatment for acromegaly have not been studied in patients who have already developed chronic congestive heart failure (CHF). We reviewed the charts of 330 consecutive patients with acromegaly treated in two French and Belgian centers since 1985. Ten patients with both acromegaly and CHF (eight men, two women, mean age 49.7 yr) were studied retrospectively. One of them was excluded because CHF was due to severe aortic stenosis. CHF ( New York Heart Association stages III-IV and echocardiography showing dilated hypokinetic cardiomyopathy with left ventricular systolic dysfunction and a left ventricular ejection fraction less than 45%) was diagnosed before, concomitantly, or after acromegaly in, respectively, two, five, and two patients. Three patients were referred with terminal heart failure requiring transplantation. One patient had transient CHF associated with a hypertensive crisis. The other eight patients had symptomatic chronic CHF. Control of GH hypersecretion failed, totally or partially, in three patients: one had a long-term survival, and the two others died at 1 and 5 yr. Good GH control was achieved in five patients: four of these are still alive 2-16 yr after diagnosis of CHF, their clinical status is stable or improved, and their quality of life is good. Overall, the 1- and 5-yr mortality ( or transplantation) rates for patients with chronic symptomatic CHF were 25% ( 2 of 8 patients) and 37.5% ( 3 of 8 patients), respectively. In conclusion, less than 3% of acromegalic patients developed CHF in this study. Although effective treatment of acromegaly improved short-term cardiovascular status, its impact on long-term survival is questionable. [less ▲]

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See detailVers une proposition de mode de détermination de la distance minimale à respecter entre les bâtiments d'élevage et les habitations.
Nicolas, Jacques ULg; Otte, Benoît

Report (2004)

Le cahier des charges de cette petite étude prévoyait trois étapes: - précision de la faisabilité des lignes-guides pour la Wallonie, - comparaison des distances calculées par les lignes-guides aux zones ... [more ▼]

Le cahier des charges de cette petite étude prévoyait trois étapes: - précision de la faisabilité des lignes-guides pour la Wallonie, - comparaison des distances calculées par les lignes-guides aux zones de nuisances olfactive évaluées par d'autres méthodes, - proposition pour une réglementation ou un guide de bonnes pratiques applicables en Wallonie. Le groupe de recherche d'Arlon a décidé de tester la faisabilité des lignes-guides existant dans d'autres pays ou régions sur base d'études de cas concrets, avec visites de terrain. En simulant, pour chacun de ces cas, la dispersion des odeurs au moyen d'un modèle de dispersion atmosphérique, il est alors possible de vérifier si les limitations spatio-temporelles ainsi déterminées par les percentiles, sur base de débits d'odeur fournis par la littérature, sont cohérentes avec les distances préconisées par les lignes-guides. Les résultats de ces deux premières étapes peuvent alors servir à jeter les bases d'une méthode adaptée à la Wallonie. [less ▲]

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See detailFeeding of planktonic rotifers on ciliates: a method using natural ciliate assemblages labelled with fluorescent microparticles
Joaquim-Justo, Célia ULg; Detry, Cédric ULg; Caufman, F. et al

in Journal of Plankton Research (2004), 26(11), 1289-1299

A method was developed to allow direct measurements of predation exerted by metazooplankton on ciliates. The method relied on the use of ciliates labelled with fluorescent microparticles (FMP). Optimal ... [more ▼]

A method was developed to allow direct measurements of predation exerted by metazooplankton on ciliates. The method relied on the use of ciliates labelled with fluorescent microparticles (FMP). Optimal labelling conditions were determined with ciliates from cultures (Tetrahymena pyriformis) and with natural ciliate assemblages sampled in a river. Labelled T. pyriformis were used as tracer food to determine gut passage time (GPT) and ingestion rates of the rotifer Brachionus calyciflorus in the laboratory. Predation of metazooplankton from the lowland river Meuse (Belgium) was determined by labelling natural assemblages of ciliates and using them as tracer food for metazooplankters sampled in the river. Optimal labels of ciliates, i.e. sharp distribution of FMP in cells, were obtained with short incubations (10 min) and low FMP concentrations (1 x 10(5) mL(-1)). GPT varied between 30 and 45 min for B. calyciflorus and from 25 up to >35 min for rotifers from the river. The ingestion rate of B. calyciflorus fed with T. pyriformis was 3.3 +/- 0.6 ciliate rot(-1) h(-1), i.e. 1.4 +/- 0.3 ngC rot(-1) h(-1). Metazooplankton species for which the ingestion of ciliates could be measured were the rotifers Keratella cochlearis, Euchlanis dilatata and Synchaeta spp. Ingestion rates measured ranged from 0.4 to 12.5 ngC rot(-1) h(-1). The method proposed proved to be useful in estimating the predation of microplankton on ciliates in semi- in situ conditions; in further developments, labelled natural assemblages of ciliates could be used for in situ incubations with the Haney chamber. [less ▲]

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See detailInterférométrie holographique sur base de cristaux photoréfractifs dynamiques et lasers à double impulsion : le projet européen PHIFE
Georges, Marc ULg; Thizy, Cédric ULg; Lemaire, Philippe et al

in Smigielski, P. (Ed.) Actes du Cinquième colloque francophone Méthodes et Techniques Optiques pour l'Industrie (2004, November)

Les cristaux photoréfractifs sont des supports holographiques dynamiques (auto-enregistrables, effaçables et indéfiniment réutilisables) qui permettent l'acquisition rapide d'hologrammes utilisables en ... [more ▼]

Les cristaux photoréfractifs sont des supports holographiques dynamiques (auto-enregistrables, effaçables et indéfiniment réutilisables) qui permettent l'acquisition rapide d'hologrammes utilisables en interférométrie holographique. De plus, certaines de leurs propriétés cristallines permettent l'obtention d'interférogrammes de qualité incomparable. Nous avons déjà présenté à maintes reprises les développements et applications d'instruments de métrologie basés sur ces cristaux avec des lasers continus. Des expériences préliminaires sur base de lasers à simple impulsion avaient aussi été montrées. Nous présentons ici la suite de ces expériences et qui ont lieu dans le cadre du projet européen PHIFE "Pulsed Holographic Interferometer for the analysis of Fast Events". PHIFE a pour objectif le développement d'un instrument à champ complet fonctionnant avec un laser YAG Q-switch à double impulsion. [less ▲]

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See detailQualification de grands réflecteurs en environnement spatial
Thizy, Cédric ULg; Stockman, Yvan ULg; Doyle, Dominic et al

in Smigielski, P. (Ed.) Actes du Cinquième colloque francophone Méthodes et Techniques Optiques pour l'Industrie (2004, November)

Les nouvelles générations de télescopes spatiaux dans le domaine infrarouge nécessitent des réflecteurs de grandes dimensions et de haute qualité. Ceux-ci, pour des raisons de poids, sont basés sur les ... [more ▼]

Les nouvelles générations de télescopes spatiaux dans le domaine infrarouge nécessitent des réflecteurs de grandes dimensions et de haute qualité. Ceux-ci, pour des raisons de poids, sont basés sur les technologies des matériaux composites dont les comportements aux basses températures sont mal connus. Une méthode par interférométrie holographique de vérification et de validation en environnement spatial de ce type de réflecteurs est présentée. Elle est basée sur l'utilisation d'une caméra holographique dynamique observant un dépoli sur lequel est projeté le faisceau objet venant de la surface réfléchissante. Outre une augmentation de la dynamique de mesure, cette méthode offre l’avantage principal, par rapport aux techniques d’interférométrie optique, de ne pas nécessiter de système optique d’adaptation du front d’onde au réflecteur à mesurer et donc un gain de flexibilité majeur pour des formes exotiques de réflecteurs (types asphériques). Le système de mesure a été calibré avec un interféromètre ponctuel à effet Doppler. L'influence des différentes sources d’erreur du système sur la mesure a été évaluée. Cette évaluation a porté principalement sur des aspects vibratoires et thermiques. Ces réflecteurs devant être testés sous vide et à basses températures, le système de mesure a été rendu compatible à ces conditions. Des éléments de la caméra holographique (objectifs, CCD, cristal, fibre optique) ont été adaptés et testés sous vide. La certification métrologique de l’ensemble du système sera réalisée par la mesure d'une antenne parabolique, de 1.1 m de diamètre de comportement connu et placée dans un environnement spatial simulé. Le test consistera à mesurer les déplacements et déformations de l'antenne entre un état initial à la température ambiante, et un état final à une température d'environ 130K. [less ▲]

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