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See detailA model for the pion structure function
Bissey, F.; Cudell, Jean-René ULg; Cugnon, Joseph ULg et al

in Physics Letters B (2002), 547(3-4), 210-218

The pion structure function is investigated in a simple model, where pion and constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma*pi ... [more ▼]

The pion structure function is investigated in a simple model, where pion and constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma*pi --> gamma*pi evaluated and related to the structure functions. It is shown that the introduction of non-perturbative effects linked to the size of the pion and preserving gauge invariance, allows a connection with the quark distribution. It is predicted that higher-twist terms become negligible for Q(2) larger than similar to 2 GeV2 and that quarks in the pion have a momentum fraction smaller than in the proton case. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailSelective encryption of uncompressed and compressed images
Van Droogenbroeck, Marc ULg

Scientific conference (2002, November 06)

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See detailTranscription of the human prolactin gene in mammary cells
Baudhuin, A.; Manfroid, Isabelle ULg; Van de Weerdt, Cécile ULg et al

in Annals of the New York Academy of Sciences (2002), 973

Expression of human prolactin in the Mammary gland, one of the main target organs of this hormone, leads to the formation of an autocrine-paracrine proliferative loop in this tissue. Involvement of ... [more ▼]

Expression of human prolactin in the Mammary gland, one of the main target organs of this hormone, leads to the formation of an autocrine-paracrine proliferative loop in this tissue. Involvement of prolactin in normal and neoplastic mammary development triggered the interest in transcriptional regulation of the human prolactin gene in mammary cells. Analysis of this regulation, and comparison to that in the pituitary, will contribute to a better understanding of mammary gland development and tumor formation. Here we present the first extensive analysis of the transcriptional regulation of the human prolactin gene in human mammary tumor cells. [less ▲]

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See detailLe cas clinique du mois. Constipation et syndrome de masse abdominale chez une patiente de 51 ans
Detrembleur, Nancy ULg; Delbecque, Katty ULg; Thiry, Albert ULg et al

in Revue Médicale de Liège (2002), 57(11), 688-91

A 51-year old patient consults for abdominal swelling and persistent constipation. Clinical exploration shows the presence of a left iliac fossa tumor corresponding to a papillary serous adenocarcinoma of ... [more ▼]

A 51-year old patient consults for abdominal swelling and persistent constipation. Clinical exploration shows the presence of a left iliac fossa tumor corresponding to a papillary serous adenocarcinoma of the fallopian tube after macroscopic and microscopic examination. The diagnostic and therapeutic problems caused by this rare gynecologic tumor are discussed. [less ▲]

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See detailMesure de coefficient de dilatation thermique de matériaux composites par holographie dynamique
Georges, Marc ULg; Ryhon, S.; Thizy, Cédric ULg et al

in Actes du 3e colloque francophone Méthodes et Techniques Optiques pour l'Industrie (2002, November)

Une méthode de mesure de coefficient de dilatation thermique par interférométrie holographique est présentée. Nous passerons rapidement en revue le principe de la caméra holographique dynamique utilisée ... [more ▼]

Une méthode de mesure de coefficient de dilatation thermique par interférométrie holographique est présentée. Nous passerons rapidement en revue le principe de la caméra holographique dynamique utilisée pour la mesure puis nous montrerons l’application à plusieurs cas concrets de R&D industriels. Il s’agit d’éprouvettes simples de matériaux composite et de structures plus complexes alliant ces matériaux à des métaux. La mesure consiste à observer le déplacement différentiel entre la partie supérieure de l’objet étudié et une plaque de base sur laquelle il est posé et ce lorsqu’un échauffement ou refroidissement de l’ensemble est opéré [less ▲]

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See detailConnexin expression and gap junctional intercellular communication in human first trimester trophoblast
Cronier, L.; Defamie, N.; Dupays, L. et al

in Molecular Human Reproduction (2002), 8(11), 1005-1013

Connexin (Cx) expression and gap junctional intercellular communication (GJIC) are involved in development and differentiation processes, and recently mutation of connexin genes has been implicated in ... [more ▼]

Connexin (Cx) expression and gap junctional intercellular communication (GJIC) are involved in development and differentiation processes, and recently mutation of connexin genes has been implicated in pathologies. In the human placenta, two distinct differentiation pathways of cytotrophoblastic cells coexist and lead to a fusion phenotype (villous trophoblast) and a proliferative/invasive phenotype (extravillous trophoblast). Here we characterized in situ and in vitro the expression of Cx transcripts and proteins in the villous and extravillous trophoblast of first trimester placenta. In addition, the GJIC functionality was investigated using the gap-fluorescence recovery after photobleaching (gap-FRAP) method. We demonstrated in the villous trophoblast the presence of Cx43 mRNA and of Cx43 protein localized between cytotrophoblastic cells and between cytotrophoblastic cells and syncytiotrophoblast. In vitro, a transient functional gap junctional intertrophoblastic communication was demonstrated during the trophoblast fusion leading to the multinucleated syncytiotrophoblast. During the proliferative process of the extravillous trophoblast, Cx40 is expressed in the proximal part of the cell columns. When cytotrophoblastic cells were cultured on Matrigel(R) for 2 days, alpha5beta1 integrin expression was observed concomitant with the presence of Cx40 mRNA and of Cx40 protein between the cells. No evidence for a GJIC was detected in this induced extravillous phenotype. In addition, Cx32 was detected between some aggregated cells after 72 h of culture. Our data show that the presence of Cx43 allows an inter-trophoblastic GJIC and is associated with the fusion process leading to the villous syncytiotrophoblast and that the presence of Cx40 does not allow GJIC and is associated with the extravillous phenotype. [less ▲]

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See detailL'evaluation de la qualite de vie dans les essais therapeutiques: un pas vers une approche holistique de la sante
Ethgen, Olivier ULg; Reginster, Jean-Yves ULg

in Revue Médicale de Liège (2002), 57(11), 695-700

The concept of quality of life has been widely developed over the last two decades. As they provide subjective assessment of health, quality of life measures may be broadly and relevantly applied in many ... [more ▼]

The concept of quality of life has been widely developed over the last two decades. As they provide subjective assessment of health, quality of life measures may be broadly and relevantly applied in many areas. Numerous measures are available today to perform discriminative, evaluative or analytical studies in the epidemiological, the therapeutic or the health economic fields. Such measures are increasingly used and may be added to clinical, biological or radiographical criteria to assess medical benefits and health outcomes in order to strengthen decisional choice in health. [less ▲]

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See detailExperimental evidence for N recycling in the leaves of the seagrass Posidonia oceanica
Lepoint, Gilles ULg; Defawe, Olivier; Gobert, Sylvie ULg et al

in Journal of Sea Research (2002), 48(3), 173-179

A one-year in situ experiment using N-15 as a tracer was designed to assess the N recycling in the leaves of the seagrass Posidonia oceanica (L.) Delile. R oceanica was shown to partly recycle the ... [more ▼]

A one-year in situ experiment using N-15 as a tracer was designed to assess the N recycling in the leaves of the seagrass Posidonia oceanica (L.) Delile. R oceanica was shown to partly recycle the internal nitrogen pool of its leaves in order to contribute to new leaf growth. The leaves sampled in June 1999 contained 20% of the quantity of N-15 found in June 1998. N recycling caused a difference between N and biomass turnover rate (0.8 vs 1.3 y(-1)) of Posidonia leaves. This 40% difference should correspond to the contribution of recycled N to the annual N requirement of Posidonia leaves. The N recycling appears to be insufficient to significantly reduce the quantitative impact of N loss due to autumnal leaf fall. However, new leaf growth between June and October is mainly sustained by this recycling because the tracer concentration in new leaves was the same as in the other leaves. By contrast, tracer concentration decreased drastically between October 1998 and June 1999, showing the more important contribution of N uptake during winter and spring. Nevertheless, recycling occurs throughout the year as demonstrated by the presence of tracer in the youngest leaves of shoots sampled one year after the tracer addition. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailEffect of aggregation on bacteriochlorin a triplet-state formation: A laser flash photolysis study
Damoiseau, Xavier; Tfibel, Francis; Hoebeke, Maryse ULg et al

in Photochemistry & Photobiology (2002), 76(5), 480-485

Bacteriochlorin a (BCA) is a potential photosensitizer for photodynamic therapy of cancer. It has been shown previously that the photoefficiency of the dye is mainly dependent on singlet oxygen (O-1(2 ... [more ▼]

Bacteriochlorin a (BCA) is a potential photosensitizer for photodynamic therapy of cancer. It has been shown previously that the photoefficiency of the dye is mainly dependent on singlet oxygen (O-1(2)) generation. Nanosecond laser flash photolysis was used to produce and to investigate the excited triplet state of the dye in methanol, phosphate buffer and dimiristoyl-L-alpha-phosphatidylcholine (DMPC) liposomes. The transients were characterized in terms of their absorption spectra, decay kinetics, molar absorption coefficients and formation quantum yield of singlet-triplet intercrossing. The lifetime of the BCA triplet state was measured at room temperature. The triplet-state quantum yield is quite high in methanol (0.7) and in DMPC (0.4) but only 0.095 in phosphate buffer. In the last case, BCA is in a monomer-dimer equilibrium, and the low value of the quantum yield observed was ascribed to the fact the triplet state is only formed by the monomers. [less ▲]

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See detailProceeds from the European workshop: GBS neonatal disease prevention
MELIN, Pierrette ULg

in de la Rosa, Manuel (Ed.) Proceedings from the European workshop: GBS neonatal disease prevention (2002)

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See detailSynergistic activation of human immunodeficiency virus type 1 promoter activity by NF-kappa B and inhibitors of deacetylases: Potential perspectives for the development of therapeutic strategies
Quivy, Vincent; Adam, Emmanuelle; Collette, Yves et al

in Journal of Virology (2002), 76(21), 11091-11103

The transcription factor NF-kappaB plays a central role in the human immunodeficiency virus type 1 (HIV-1) activation pathway. HIV-1 transcription is also regulated by protein acetylation, since treatment ... [more ▼]

The transcription factor NF-kappaB plays a central role in the human immunodeficiency virus type 1 (HIV-1) activation pathway. HIV-1 transcription is also regulated by protein acetylation, since treatment with deacetylase inhibitors such as trichostatin A (TSA) or sodium butyrate (NaBut) markedly induces HIV-1 transcriptional activity of the long terminal repeat (LTR) promoter. Here, we demonstrate that TSA (NaBut) synergized with both ectopically expressed p50/p65 and tumor necrosis factor alpha/SF2 (TNF)-induced NF-kappaB to activate the LTR. This was confirmed for LTRs from subtypes A through G of the HIV-1 major group, with a positive correlation between the number Of kappaB sites present in the LTRs and the amplitude of the TNF-TSA synergism. Mechanistically, TSA (NaBut) delayed the cytoplasmic recovery of the inhibitory protein IkappaBalpha. This coincided with a prolonged intranuclear presence and DNA binding activity of NF-kappaB. The physiological relevance of the TNF-TSA (NaBut) synergism was shown on HIV-1 replication in both acutely and latently HIV-infected cell lines. Therefore, our results open new therapeutic strategies aimed at decreasing or eliminating the pool of latently HIV-infected reservoirs by forcing viral expression. [less ▲]

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See detailQuaternary folding in the south piedmont of central segment of Tianshan Mountains
Huafu, Lu; Dong, Jia; Suppe, J. et al

in Chinese Science Bulletin (2002), 47

The Tianshan Mountains are an important active structural belt in the interior of Eurasia. By integrated methods of surface geology survey and interpretation of seismic profiles, we distinguish fold ... [more ▼]

The Tianshan Mountains are an important active structural belt in the interior of Eurasia. By integrated methods of surface geology survey and interpretation of seismic profiles, we distinguish fold scarps located at the south limb of the Kuqatawu anticline and the north limb of the Dongqiulitag anticline in the Kuqa rejuvenation foreland thrust belt, south piedmont of central segment of the Tian- shan Mountains. Fold scarp is a newly found structural phenomenon. Because of the bend of thrust plane and the movement of hanging wall above the thrust plane, the origi- nal horizontal deposits of hanging wall and their surface become a monocline structure, resulting from the separating and migration of the active and fixed axial surfaces. Meas- uring the geometry of fold scarp and using the data of age of the deformed deposits, the crustal shortening rate resulting from the deeply seated subsurface thrust is calculated. The crustal shortening rate reflected by the fold scarp located at the north limb of the Dngqiulitag anticline is (1␣0.1) mm/a. The fold scarps of the Dongqiulitag anticline and the Ku- qatawu anticline identify that the deformation process of the crustal compressive structures in the Kuqa area extends into the Late Quaternary. [less ▲]

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See detailRole of endocrine status and cell type in adhesion of human endometrial cells to the peritoneum in nude mice
Beliard, Aude ULg; Noël, Agnès ULg; Goffin, Frédéric ULg et al

in Fertility and Sterility (2002), 78(5), 973-978

Objective: To investigate the role of different cellular types (epithelial and stromal endometrial cells and peritoneal cells) in the ectopic implantation of endometrium and to evaluate the importance of ... [more ▼]

Objective: To investigate the role of different cellular types (epithelial and stromal endometrial cells and peritoneal cells) in the ectopic implantation of endometrium and to evaluate the importance of endocrine environment on the adhesion of endometrial cells to the peritoneum. Design: Experimental prospective study. Setting: University hospital, department of cell biology. Animal(s): One hundred one nude mice. Intervention(s): Monolayer culture of human epithelial and stromal endometrial cells obtained from patients undergoing hysterectomy or laparoscopy for benign disease. Intraperitoneal injection of cells into nude mice. Main Outcome Measure(s): Two weeks after cell injection, adhesion of endometrial cells was evaluated by histological and immunohistochemical examination. Result(s): Mixed cultures of stromal and epithelial cells, but not purified epithelial or stromal cells alone, adhered to the mouse peritoneum and led to endometriotic-like nodules. Pretreatment of cells with estrogen alone or with estrogen and progestin resulted in a higher percentage of animals developing endometriotic-like nodules, whereas treatment with progestin alone did not affect endometriotic implantation. Conclusion(s): Our data indicate that the success of endometrial cell implantation is dependent on the cooperativeness between stromal and epithelial endometrial cells, as well as on the endocrine environment of endometrial cells, but not that of recipient animals. The results emphasize the role of both endometrial cell types for ectopic implantation. (C) 2002 by American Society for Reproductive Medicine. [less ▲]

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See detailAn XMM-Newton observation of the Lagoon Nebula and the very young open cluster NGC 6530
Rauw, Grégor ULg; Nazé, Yaël ULg; Gosset, Eric ULg et al

in Astronomy and Astrophysics (2002), 395(2), 499-513

We report the results of an XMM-Newton observation of the Lagoon Nebula (M8). Our EPIC images of this region reveal a cluster of point sources, most of which have optical counterparts inside the very ... [more ▼]

We report the results of an XMM-Newton observation of the Lagoon Nebula (M8). Our EPIC images of this region reveal a cluster of point sources, most of which have optical counterparts inside the very young open cluster NGC6530. The bulk of these X-ray sources are probably associated with low and intermediate mass pre-main sequence stars. One of the sources experienced a flare-like increase of its X-ray flux making it the second brightest source in M8 after the O4 star 9 Sgr. The X-ray spectra of most of the brightest sources can be fitted with thermal plasma models with temperatures of kT similar to a few keV. Only a few of the X-ray selected PMS candidates are known to display Halpha emission and were previously classified as classical T Tauri stars. This suggests that most of the X-ray emitting PMS stars in NGC6530 are weak-line T Tauri stars. In addition to 9 Sgr, our EPIC field of view contains also a few early-type stars. The X-ray emission from HD 164816 is found to be typical for an O9.5 III-IV star. At least one of the known Herbig Be stars in NGC6530 ( LkHalpha 115) exhibits a relatively strong X-ray emission, while most of the main sequence stars of spectral type B1 and later are not detected. We also detect ( probably) diffuse X-ray emission from the Hourglass Region that might reveal a hot bubble blown by the stellar wind of Herschel 36, the ionizing star of the Hourglass Region. [less ▲]

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See detailImprovement of the interaction formulae for beam columns in Eurocode 3
Boissonnade, N.; Jaspart, Jean-Pierre ULg; Muzeau, J. P. et al

in Computers & Structures (2002), 80(27-30), 2375-2385

This paper presents a new proposal for beam-column interaction formulae initially based on second-order in-plane elastic theory, as an alternative to those proposed in the Eurocode 3 pre-standard [1]. It ... [more ▼]

This paper presents a new proposal for beam-column interaction formulae initially based on second-order in-plane elastic theory, as an alternative to those proposed in the Eurocode 3 pre-standard [1]. It has been derived according to the following requirements: theoretical background, clear physical meaning, consistency with the other related formulae of Eurocode 3 and accuracy. Besides that, the suggested formulae cover all required continuities: between the cross-section classes, from plasticity to elasticity as slenderness and axial force increase, and continuity between all the individual stability member checks and cross-section verifications. Further to the presentation of the formulae and their background, the good agreement of the proposal is shown through an extensive comparison with more than 15,000 results of finite element numerical simulations. (C) 2002 Civil-Comp Ltd. and Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailLe medicament du mois. L'association budesonide 160 micrograms/formoterol 4.5 micrograms (Symbicort TH)
Louis, Renaud ULg

in Revue Médicale de Liège (2002), 57(11), 741-4

The combination of budesonide 160 micrograms/formoterol 4.5 micrograms (Symbicort TH) in the same dry powder inhaler (turbohaler) results in a drug that possesses powerful bronchial anti-inflammatory ... [more ▼]

The combination of budesonide 160 micrograms/formoterol 4.5 micrograms (Symbicort TH) in the same dry powder inhaler (turbohaler) results in a drug that possesses powerful bronchial anti-inflammatory, bronchoprotective and bronchodilating activities. Symbicort TH is registered as a maintenance treatment for asthma from the age of 12 years. This drug is indicated in the treatment of moderate and severe persistent asthma as well as in asthma which remains mild persistent despite the regular use of low doses of inhaled corticoids alone. Symbicort TH rapidly improves asthma control by reducing symptoms, relief medication consumption and by improving lung function. Importantly, when taken regularly over a prolonged period, the drug reduces the number of mild and severe exacerbations. The dose of Symbicort TH is adjustable according to the disease severity and generally fluctuates between 2 x 1/24 h and 4 x 2/24 h. Symbicort TH is a simple and a efficient treatment likely to improve the compliance of asthmatics to their treatment in real life. [less ▲]

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See detailCannabis, situation en 2001-2002
Noirfalise, Alfred ULg; Gosset, Christiane ULg; Maisse, L.

in Revue Médicale de Liège (2002), 57(11), 692-4

Even though its use becomes common, cannabis remains a narcotic, the risks of which are nowadays better known. Its therapeutic value still needs to be scientifically demonstrated.

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See detailAnalyse des opportunités de transport de conteneurs par la voie fluviale entre les ports de Liège, d'Anvers et de Rotterdam
Marchal, Jean ULg

in Special Lloyd, Annuaire du Port de Liège 2002 (2002)

Le transport est une activité socio-économique fondamentale qui joue un rôle complexe et multiple dans le fonctionnement et dans le mécanisme du développement d’un pays ou d’une région. Une bonne marche ... [more ▼]

Le transport est une activité socio-économique fondamentale qui joue un rôle complexe et multiple dans le fonctionnement et dans le mécanisme du développement d’un pays ou d’une région. Une bonne marche couronnée de succès du système économique et social d’une région est en effet étroitement liée au transport de qualité organisé rationnellement. Sur base de ces considérations, il est clair que l’activité « transport » intègre un grand nombre de composantes et son impact déborde largement les seuls utilisateurs. A cet aspect pluridisciplinaire de l’activité « transport », il faut ajouter son évolution vers des solutions intermodales ; il faut en effet dépasser la simple organisation de la concurrence pour assurer la complémentarité des modes de transport, ce qui naturellement génère l’émergence de la logistique intégrée devenue une activité majeure pour tendre vers un optimum du transfert origine-destination. Dans une perspective de concurrence intermodale équitable, il convient que l’évaluation comparative se fasse sur un plan socio-économique, tenant compte à la fois des coûts internes et externes. Il faut mobiliser les différents niveaux de pouvoir et de compétence et veiller particulièrement à ce que les avancées en matière de libéralisation et de mise en concurrence et les politiques sectorielles s’inscrivent pleinement dans l’objectif d’une mobilité durable. Ces principes de base ont sous-tendus la présente analyse du « Pôle Transport de la région liégeoise » relative à l’opportunité de transférer du conteneur du port de Liège (plate-forme de Renory) vers les ports d’Anvers et de Rotterdam, principalement par la voie d’eau, alors qu’actuellement ce transfert est réalisé par la route. [less ▲]

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See detailLe mélèze en Région wallonne. Etat des lieux et stations potentielles
Claessens, Hugues ULg; Lecomte, H.; Pauwels, D.

in Forêt Wallonne (2002), (61), 4-9

Le mélèze a été introduit en Belgique dans la deuxième moitié du XVIIIe siècle. Il s’agissait alors du mélèze d’Europe, surtout implanté à des fins esthétiques ou d’enrichissement de forêts feuillues ... [more ▼]

Le mélèze a été introduit en Belgique dans la deuxième moitié du XVIIIe siècle. Il s’agissait alors du mélèze d’Europe, surtout implanté à des fins esthétiques ou d’enrichissement de forêts feuillues. Quant au mélèze du Japon, il a été importé en Europe à la fin du XIXe siècle. Ce n’est qu’à partir des années ’50 que les mélèzes ont eu du succès auprès des sylviculteurs. Ils l’ont planté le plus souvent par parquets purs après d’autres résineux ou en transformation de peuplements feuillus de faible qualité sylvicole. Mais comme le montrera l’inventaire forestier wallon en 1980, ce succès fut de courte durée. [less ▲]

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