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See detailIMAGE FUV and in situ FAST particle observations of substorm aurorae
Mende, S. B.; Carlson, C. W.; Frey, H. U. et al

in Journal of Geophysical Research. Space Physics (2003), 108

Images from the IMAGE Wide-band Imaging Camera (WIC) and Spectrographic Imager (SI) channels SI-12 and SI-13 were compared to in situ data taken by FAST during several substorms. FAST spacecraft ... [more ▼]

Images from the IMAGE Wide-band Imaging Camera (WIC) and Spectrographic Imager (SI) channels SI-12 and SI-13 were compared to in situ data taken by FAST during several substorms. FAST spacecraft observations have shown that the high latitude auroral ionosphere has several distinct regions. Intense auroras are seen in regions of upward directed quasi static electric fields and of Alfven wave accelerated superthermal electrons. In two of the cases presented, the satellite passed through an active poleward propagating substorm surge on its duskward flank. Both show that the superthermal wave accelerated component to be on the polar cap boundary of the surge, and that it could be distinguished from quasi static field ``inverted V'' precipitation which occurred at the more equatorward parts of the auroral oval. In one of these cases, the surge was accompanied by intense ion outflow. Three cases showed the FAST satellite passing through the substorm aurora at midnight or the dawn side outside of the surge and the wave accelerated electrons were less clearly separated from the inverted V type precipitation. The wave accelerated electrons were seen to be part of very short-lived transient events, i.e., bursts. The region of auroral forms, associated with Alfven waves exhibit relatively soft auroral precipitation with very intense electron fluxes. By comparing the intensity of the WIC and SI-13 channels of IMAGE FUV, it is possible sometimes to distinguish optically between the two types of regions. Global imaging of the two regions would allow the separation of quasi-static plasma convection regions containing inverted V-s from regions of Alfven wave driven electrons signifying substorm related magnetic field dynamics. [less ▲]

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See detailGeographical traceabilitiy of food products.
Tychon, Bernard ULg; Oger, Robert ULg

Conference (2003, March)

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See detailIndividualisme, autonomie et dépendance dans la société contemporaine
Jacquemain, Marc ULg

Scientific conference (2003, March)

Du point de vue de la logique sociologique des conséquences inattendues, le papier tente de montrer que la véritable autonomie, comme le dit bien Richard Sennett, n'est de ne pas dépendre de personne (ce ... [more ▼]

Du point de vue de la logique sociologique des conséquences inattendues, le papier tente de montrer que la véritable autonomie, comme le dit bien Richard Sennett, n'est de ne pas dépendre de personne (ce qui définit la solitude ou l'exclusion), mais qu'elle se construit dans l'interdépendance mutuelle. L'article reprend et développe un des arguments esquissés dans "La Raison névrotique" [less ▲]

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See detailAnomalies du metabolisme osseux chez les patients infectes par le HIV et traites par tritherapie
GIOT, Jean-Baptiste ULg; Franchimont, N.; Moutschen, Michel ULg

in Revue Médicale de Liège (2003), 58(3), 155-63

For several years already, a growing number of studies reports modifications in the bone metabolism among HIV-infected patients. Some of these studies, published even before the use of HAART, involved the ... [more ▼]

For several years already, a growing number of studies reports modifications in the bone metabolism among HIV-infected patients. Some of these studies, published even before the use of HAART, involved the infection itself. With the experience already available as concerns HAART, antiretroviral treatments (ART) seem however to be called into question. Data are divergent yet. Some studies tend to invalidate the collected data about the harmful role of HAART and prove the absence of effect or even the beneficial action of ART on bone. Moreover, the three important classes of ART are implied, even if the proteases inhibitors are most commonly charged. Pathogenic mechanism remain hypothetical. While the impact on morbidity seems to be weak for the time being, long-term repercussions are still unknown, in particular when children are concerned. In such conditions, it appears difficult to set up coherent politics of screening, prevention and treatment. Nevertheless beyond the divergences, the multifactorial character of alteration of HIV-infected patient's bone metabolism seems to be undeniable. The identification of the different parameters should in the future clarify the situation and enable the publishing of exact criteria of screening, prevention and treatment. [less ▲]

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See detailGeneralized (m, k)-Zipf law for fractional Brownian motion-like time series with or without effect of an additional linear trend
Bronlet, Philippe ULg; Ausloos, Marcel ULg

in International Journal of Modern Physics C (2003), 14(3), 351-365

We have translated fractional Brownian motion (FBM) signals into a text based on two "letters", as if the signal fluctuations correspond to a constant stepsize random walk. We have applied the Zipf method ... [more ▼]

We have translated fractional Brownian motion (FBM) signals into a text based on two "letters", as if the signal fluctuations correspond to a constant stepsize random walk. We have applied the Zipf method to extract the zeta' exponent relating the word frequency and its rank on a log-log plot. We have studied the variation of the Zipf exponent(s) giving the relationship between the frequency of occurrence of words of length m < 8 made of such two letters: zeta' is varying as a power law in terms of m. We have also searched how the zeta' exponent of the Zipf law is influenced by a linear trend and the resulting effect of its slope. We can distinguish finite size effects, and results depending whether the starting FBM is persistent or not, i.e., depending on the FBM Hurst exponent H. It seems then numerically proven that the Zipf exponent of a persistent signal is more influenced by the trend than that of an antipersistent signal. It appears that the conjectured law zeta' = \2H - 1\ only holds near H = 0.5. We have also introduced considerations based on the notion of a time dependent Zipf law along the signal. [less ▲]

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See detailL'image du mois. Artere coronaire unique ou tronc commun occlus collateralise?
Gach, Olivier ULg; Troisfontaines, Paul ULg; Legrand, Victor ULg

in Revue Médicale de Liège (2003), 58(3), 117-8

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See detailConfigurations and Modulation Schemes Trade-off
Absil, Olivier ULg

in Lacoste, H. (Ed.) GENIE - DARWIN Workshop - Hunting for Planets (2003, March)

During the preliminary phase A of the Ground-based European Nulling Interferometer Experiment (GENIE), a number of interferometric configurations have been studied, in the cases of exozodiacal cloud and ... [more ▼]

During the preliminary phase A of the Ground-based European Nulling Interferometer Experiment (GENIE), a number of interferometric configurations have been studied, in the cases of exozodiacal cloud and hot Jupiter detection. Their expected performances have been computed in light of the measured or expected performances of the VLTI subsystems. A simple Bracewell nulling interferometer, formed of two Unit Telescopes and working in the L’ or N bands, has been identified as a good candidate configuration for exozodiacal cloud detection. External or internal chopping, fringe tracking and intensity matching will be critical issues for this configuration. In the case of hot Jupiter detection, a double Bracewell with internal modulation in the L’ band seems well appropriate, and should allow to carry out low resolution spectroscopy on a few bright exoplanets. The basic assumptions and computations which have lead to these candidate configurations are described in this paper. [less ▲]

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See detailAnalysis of selected halogenated contaminants using SBSE-TD-PTV-GCxGC-IDTOFMS
Focant, Jean-François ULg; Sjodin; Needham et al

Poster (2003, March)

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See detailIsokinetic assessment of knee flexors and extensors in professional soccer players
Croisier, Jean-Louis ULg; Réveillon, Vincent; Ferret, J. M. et al

in Isokinetics & Exercise Science (2003, March), 11(1), 61-62

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See detailToxicite pulmonaire de la gemcitabine dans le cadre d'un CPNPC avec carcinomatose cerebrale
Mommens, Véronique; Bosquee, Léon ULg; D'Orio, Vincenzo ULg

in Revue Médicale de Liège (2003), 58(3), 123-6

Gemcitabine pulmonary toxicity is rare and represents a difficult diagnosis. A 61 year old female treated with gemcitabine for a metastatic non-small cell lung cancer (NSCLC) developed during the fifth ... [more ▼]

Gemcitabine pulmonary toxicity is rare and represents a difficult diagnosis. A 61 year old female treated with gemcitabine for a metastatic non-small cell lung cancer (NSCLC) developed during the fifth chemotherapy cycle an acute respiratory distress syndrome with fever, tachypnea, marked hypoxemia and a diffuse interstitial-alveolar infiltrate on chest radiograph. No infectious or opportunistic etiology or cardiovascular disease was demonstrated. Withdrawal of gemcitabine and administration of corticosteroids led to symptomatic improvement. This acute pneumonitis was likely drug induced. [less ▲]

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See detailAn observational study of line-profile variable B stars
Briquet, Maryline ULg

Doctoral thesis (2003)

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See detailShoulder isokinetic exploration following shoulder rotator cuff suture
Binet, J.; Forthomme, Bénédicte ULg; Bierlaire, J. P. et al

in Isokinetics & Exercise Science (2003, March), 11

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See detailChanger l’organisation du « système » TRM* en radio-oncologie par l’introduction d’un apprentissage organisationnel pour faciliter la mise en place des progrès technologiques.
COUCKE, Philippe ULg

Master of advanced studies dissertation (2003)

Le service de radio-oncologie est caractérisé par la technicité et la complexité toujours en évolution de la prise en charge thérapeutique. Le développement dans ce domaine est tel que le service de radio ... [more ▼]

Le service de radio-oncologie est caractérisé par la technicité et la complexité toujours en évolution de la prise en charge thérapeutique. Le développement dans ce domaine est tel que le service de radio-oncologie risque très rapidement d’être déphasé par rapport à la qualité de la prise en charge que le patient est en mesure d’attendre dans les limites des ressources disponibles. Si l’organisation n’est pas apte à prendre en compte la nécessité d’une amélioration continue, nous ne serons plus capables d’assurer des soins de haute qualité auquel le patient a droit, et nous perdrons rapidement l’habilité technique dans la pratique des soins. Afin d’assurer la maîtrise et la pérennité d’une prise en charge de haute qualité nous voulons mettre en route une démarche globale d’amélioration continue qui doit finalement aboutir à une démarche de projet de qualité et de certification. Nous faisons le constat, aujourd’hui, que le groupe des techniciens en radiologie médicale* ne répond pas aux critères d’une organisation apprenante qui est une condition sine qua non pour l’amélioration continue. Afin de modifier cette situation, il nous faut définir un facteur suffisamment puissant pour déclencher cet évolution d’état d’esprit. Ce changement sera abordé par la mise en place d’une mesure de satisfaction au sein même du système TRM en collaboration avec la cellule ESOP de l’Institut Universitaire de Médecine sociale et Préventive (IUMSP). Cette démarche basée sur un « brainstorming » dont la trame de réflexion pourrait être l’évaluation du niveau atteint dans la pyramide de satisfaction de Maslow par les TRM (analyse interne du système). Ce genre d’exercice effectué par les TRM pourrait aboutir à une visualisation structurée de la problématique du manque d’amélioration continue et des causes de l’absence d’une telle organisation apprenante en utilisant la technique du diagramme d’Ishikawa. L’avantage de cette démarche, c’est que le groupe TRM en tant que tel va aboutir à l’élaboration active d’un certain nombre d’idées clés censées amener une solution aux problèmes énoncés. En même temps nous voulons déclencher une redéfinition de la vision d’entreprise et des tâches et des compétences requises (une formulation claire des exigences en termes qualitatifs et quantitatifs de l’attente du service vis-à-vis des TRM) ; cette tâche incombe aux mandataires du changement c’est-à-dire les médecins et le groupe des physiciens qui font partie de l’environnement immédiat du système TRM, et qui ont besoin d’une amélioration continue du savoir (savoir, savoir être et savoir faire) des TRM afin de pouvoir implémenter des nouvelles techniques complexes en radio-oncologie. Cette « analyse externe » va permettre de définir des objectifs clairs et une vision commune. Le constat de la différence entre l’analyse externe et interne doit aboutir à un travail de groupe mixte (TRM et mandataires) afin de déboucher sur une concordance des deux visions. Afin de faire participer les TRM à l’élaboration des idées-clés des solutions, la mise en place desdites solutions et l’évaluation de l’efficacité des solutions mises en place, nous prévoyons de créer différents groupes de travail ayant chacun un objectif clair et précis (exemple : mise en place de l’utilisation en routine de l’imagerie portale pour le contrôle de qualité systématique des champs d’irradiation). Cette démarche va provoquer un changement fondamental dans le système TRM, une évolution d’une organisation primaire vers une organisation secondaire travaillant par objectifs, plus apte à s’adapter aux exigences de l’environnement, capable d’anticiper et non pas de subir les mises à jour technologiques. Par la même occasion, cette démarche une fois amorcée va obliger l’intégralité du service de radio-oncologie à établir un référentiel d’auto-évaluation et un guide des procédures qui vont permettre à terme d’aboutir sur une certification ISO 9001-2000. *Le genre masculin du titre professionnel s’entend bien entendu également au féminin. [less ▲]

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See detailMembrane type-1 matrix metalloproteinase and TIMP-2 in tumor angiogenesis
Sounni, Nor Eddine ULg; Janssen, M.; Foidart, Jean-Michel ULg et al

in Matrix Biology (2003), 22(1), 55-61

The matrix metalloproteinases (MMPs) constitute a multigene family of over 23 secreted and cell-surface associated enzymes that cleave or degrade various pericellular substrates. In addition to virtually ... [more ▼]

The matrix metalloproteinases (MMPs) constitute a multigene family of over 23 secreted and cell-surface associated enzymes that cleave or degrade various pericellular substrates. In addition to virtually all extracellular matrix (ECM) compounds, their targets include other proteinases, chemotactic molecules, latent growth factors, growth factor-binding proteins and cell surface molecules. The MMP activity is controlled by the physiological tissue inhibitors of MMPs (TIMPs). There is much evidence that MMPs and their inhibitors play a key role during extracellular remodeling in physiological situations and in cancer progression. They have other functions that promoting tumor invasion. Indeed, they regulate early stages of tumor progression such as tumor growth and angiogenesis. Membrane type MMPs (MT-MMPs) constitute a new subset of cell surface-associated MMPs. The present review will focus on MT1-MMP which plays a major role at least, in the ECM remodeling, directly by degrading several of its components, and indirectly by activating pro-MMP2. As our knowledge on the field of MT1-MMP biology has grown, the unforeseen complexities of this enzyme and its interaction with its inhibitor TIMP-2 have emerged, often revealing unexpected mechanisms of action. (C) 2003 Elsevier Science B.V/Intemational Society of Matrix Biology. All rights reserved. [less ▲]

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See detailAdhesion of endometrial cells labeled with 111 Indium-tropolonate to peritoneum: a novel in vitro model to study endometriosis
Beliard, Aude ULg; Noël, Agnès ULg; Goffin, Frédéric ULg et al

in Fertility and Sterility (2003), 79(Suppl. 1), 724-729

Objective: To evaluate, in a new original in vitro assay, putative factors that could modulate the adhesion of endometrial cells to peritoneum. Design: Prospective, controlled in vitro study. Setting ... [more ▼]

Objective: To evaluate, in a new original in vitro assay, putative factors that could modulate the adhesion of endometrial cells to peritoneum. Design: Prospective, controlled in vitro study. Setting: Academic research laboratory. Patient(s): Fourteen nonmenopausal women undergoing hysterectomy or laparoscopy for benign gynecologic indication. Intervention(s): Endometrial cells obtained from women with regular cycles without endometriosis were labeled with (111)Indium and confronted in vitro with mouse peritoneum in the presence of various cytokines and/or antiadhesive compounds. Main Outcome Measure(s): Radioactivity in (111)Indium-labeled endometrial cells. Result(s): The adhesion of human endometrial cells to mouse peritoneum was increased by treatment with pro-inflammatory cytokines (interleukin IL-1 beta, IL-6, TNF alpha, TGF-beta1). Whereas heparan sulfate had no effect on cell adhesion, a gel of ferric hyaluronate (Intergel) was able to counteract the pro-adhesive effect of cytokines. Interestingly, the pretreatment of peritoneum with cytokines, 24 hours before cell seeding in the presence of the ferric hyaluronate gel, restored the cytokine-promoting effect on cell adhesion. Conclusion(s): Proinflammatory cytokines promote the in vitro peritoneal adhesion of endometrial cells. An antiadhesive hyaluronate gel used in clinics decreases the adhesion in a dose-dependent manner and reduces cytokine bioavailability. (Fertil Steril((R)) 2003;79(Suppl 1):724-9. (C) 2003 by American Society for Reproductive Medicine.). [less ▲]

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See detailJeunesse, quartiers, violence : pour une politique de prévention intégrée
Comeron, Manuel ULg

in Manuel de la Police (2003), (67), 166

La violence juvénile, particulièrement dans les quartiers, constitue un problème majeur de sécurité urbaine. A l'éclairage des travaux scientifiques sur la déviance sociale et la délinquance juvénile, les ... [more ▼]

La violence juvénile, particulièrement dans les quartiers, constitue un problème majeur de sécurité urbaine. A l'éclairage des travaux scientifiques sur la déviance sociale et la délinquance juvénile, les intervenants sociaux et services de police construisent des actions communes afin de proposer une réponse préventive intégrée. [less ▲]

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See detailA comparison of voluntary and electrically induced contractions by interleaved H-1- and P-31-NMRS in humans
Vanderthommen, Marc ULg; Duteil, S.; Wary, C. et al

in Journal of Applied Physiology (2003), 94(3), 1012-1024

Skeletal muscle voluntary contractions (VC) and electrical stimulations (ES) were compared in eight healthy men. High-energy phosphates and myoglobin oxygenation were simultaneously monitored in the ... [more ▼]

Skeletal muscle voluntary contractions (VC) and electrical stimulations (ES) were compared in eight healthy men. High-energy phosphates and myoglobin oxygenation were simultaneously monitored in the quadriceps by interleaved H-1- and P-31-NMR spectroscopy. For the VC protocol, subjects performed five or six bouts of 5 min with a workload increment of 10% of maximal voluntary torque (MVT) at each step. The ES protocol consisted of a 13-min exercise with a load corresponding to 10% MVT. For both protocols, exercise consisted of 6-s isometric contractions and 6-s rest cycles. For an identical mechanical level (10% MVT), ES induced larger changes than VC in the P-i-to-phosphocreatine ratio [1.38 +/- 1.14 (ES) vs. 0.13 +/- 0.04 (VC)], pH [6.69 +/- 0.11 (ES) vs. 7.04 +/- 0.07 (VC)] and myoglobin desaturation [43 +/- 15.9 (ES) vs. 6.1 +/- 4.6% (VC)]. ES activated the muscle facing the NMR coil to a greater extent than did VCs when evaluated under identical technical conditions. This metabolic pattern can be interpreted in terms of specific temporal and spatial muscle cell recruitment. Furthermore, at identical levels of energy charge, the muscle was more acidotic and cytoplasm appeared more oxygenated during ES than during VC. These results are in accordance with a preferential recruitment of type II fibers and a relative muscle hyperperfusion during ES. [less ▲]

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See detailImage analysis of the axonal ingrowth into poly(D,L-lactide) porous scaffolds in relation to the 3-D porous structure
Blacher, Silvia ULg; Maquet, Véronique; Luyckx, Françoise ULg et al

in Biomaterials (2003), 24(6), 1033-1040

Porous polymer scaffolds are promising materials for neural tissue engineering because they offer valuable three-dimensional (3D) supports for the in vitro and in vivo axonal growth and tissue expansion ... [more ▼]

Porous polymer scaffolds are promising materials for neural tissue engineering because they offer valuable three-dimensional (3D) supports for the in vitro and in vivo axonal growth and tissue expansion. At the time being, how the in vivo neuronal cell development depends on the scaffold 3-D architecture is unknown. Therefore, scanning electron micrographs of longitudinal sections of porous polylactide scaffolds and immunohistological sections of these scaffolds after implantation and neurofilament staining have been studied by image analysis. Pore orientation and axonal ingrowth have been investigated by spectral analysis on gray level SEM images. Binary image processing has been carried out and the binary images have been studied by spectral analysis in order to estimate the possible effect of the image noise on the real pattern. In addition to axonal orientation, density and length distribution of the regenerated axons into the polymer scaffold have been measured. Dependence of the axonal ingrowth on the 3D-polymer scaffold has been discussed on the basis of the collected data. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailOzone et asthme: un couple dans l'air du temps
Kleis, S.; Louis, Renaud ULg; Bartsch, Pierre ULg

in Revue Médicale de Liège (2003), 58(3), 132-8

Ozone is a pollutant the production of which depends on weather conditions and car engine combustion. Numerous epidemiological studies have indicated that high ozone levels correlated with morbidity in ... [more ▼]

Ozone is a pollutant the production of which depends on weather conditions and car engine combustion. Numerous epidemiological studies have indicated that high ozone levels correlated with morbidity in asthma. Experimental studies have shown that exposure of healthy subjects and asthmatics to ozone levels comparable to those measured in ambient air during hot summer days can generate respiratory symptoms, neutrophilic airways inflammation and lung function impairment. Lung function changes following ozone exposure are more pronounced in asthmatics and are dependent on the duration and intensity of exposure, a previous exposure and the nutritional status of the subjects. The airway epithelial cell layer is likely to play a pivotal role in initiating the inflammatory process following ozone exposure. Control of ambient air ozone levels must be a target for public health authorities. [less ▲]

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See detailPolymer/layered silicate nanocomposites by combined intercalative polymerization and melt intercalation: a masterbatch process
Lepoittevin, Bénédicte; Pantoustier, Nadège; Devalckenaere, Myriam et al

in Polymer (2003), 44(7), 2033-2040

Poly(ε-caprolactone) (PCL) and poly(vinyl chloride) (PVC) layered silicate nanocomposites were prepared by combination of intercalative polymerization and melt intercalation. In a first step, high clay ... [more ▼]

Poly(ε-caprolactone) (PCL) and poly(vinyl chloride) (PVC) layered silicate nanocomposites were prepared by combination of intercalative polymerization and melt intercalation. In a first step, high clay content PCL nanocomposites were prepared by in situ polymerization of -caprolactone intercalated between selected organo-modified silicate layers. The polymerization was catalyzed with dibutyltin dimethoxide in the presence of montmorillonites, the surface of which were previously exchanged with (functionalized) long alkyl chains ammonium cations. Then, these highly filled PCL nanocomposites were added as masterbatches in commercial PCL and PVC by melt blending. The intercalation of PCL chains within the silicate layers by in situ polymerization proved to be very efficient, leading to the formation of intercalated and/or exfoliated structures depending on the organo-clay. These masterbatches were readily dispersed into the molten PCL and PVC matrices yielding intercalated/exfoliated layered silicate nanocomposites which could not be obtained by melt blending the matrix directly with the same organo-modified clays. The formation of nanocomposites was assessed both by X-ray diffraction and transmission electronic microscopy. Interestingly, this so-called 'masterbatch' two-step process allowed for preparing PCL nanocomposites even with non-modified natural clay, i.e. sodium montmorillonite, which showed a material stiffness much higher than the corresponding microcomposites recovered by direct melt intercalation. The thermal stability of PCL nanocomposites as a function of clay content was investigated by thermogravimetry (TGA). [less ▲]

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