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See detailEndometriose stade I et II: implications physiopathologiques, cliniques et therapeutiques
Nisolle, Michelle ULg; Nervo, Patricia ULg

in Journal de Gynécologie, Obstétrique et Biologie de la Reproduction (2003), 32(8, Pt 2), 11-4

Stage I and II endometriosis is defined by a r-AFS score respectively ranging from 1 to 5 and from 6 to 15. This mild, superficial endometriosis is a very common pathology occurring in infertile women ... [more ▼]

Stage I and II endometriosis is defined by a r-AFS score respectively ranging from 1 to 5 and from 6 to 15. This mild, superficial endometriosis is a very common pathology occurring in infertile women. Nevertheless, these women with stage I/II endometriosis have usually few pelvic pain. This review summarizes the recent literature concerning new data on the pathogenesis of peritoneal endometriosis and its clinical management. Retrograde menstruation, peritoneal adhesion of shed endometrial tissue, and outgrowth of endometrial cells, glands and stroma, are essential elements in the pathogenesis of endometriosis according to Sampson's classic implantation theory. Nevertheless, exact pathophysiology of endometriosis remains unknown. Superficial endometriotic lesions observed by laparoscopy have to be treated. Surgical procedure is not difficult for stage I and II of endometriosis. Surgical procedure remains controversial. Carbon dioxide (CO2) Laser can be used for laparoscopic destruction of endometriosis. Newer procedures, such as SurgiTouch (Lumenis), are more effective in vaporization and decrease the risk thermal damage of contiguous structures. The monopolar scissors can also be used in order to excise the peritoneal endometriotic lesions. Medical treatment may be usefull if surgical treatment is not complete or if the pelvic cavity is hypervascularized. In these cases, Gonadotropin-Releasing Hormone agonists (Gn-RHa) are the most common and effective treatment. [less ▲]

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See detailL'image du mois. Myxome de l'oreillette gauche
Tombeux, Christophe ULg; Davin, Laurent ULg; PIERARD, Luc ULg et al

in Revue Médicale de Liège (2003), 58(12), 723

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See detailTowards a consistant safety format of steel beam-columns: application of the new interaction formulae for ambient temperature to elevated temperatures
Vila Real, Paulo; Lopes, Nuno; da Silva, Luis et al

in Steel & Composite Structures (2003), 3(6), 383-401

Two new formulae for the design of beam-columns at room temperature have been proposed into Eurocode 3, prEN 1993-1-1 (2002), and are the result of great efforts made by two working groups that followed ... [more ▼]

Two new formulae for the design of beam-columns at room temperature have been proposed into Eurocode 3, prEN 1993-1-1 (2002), and are the result of great efforts made by two working groups that followed different approaches, a French-Belgian team and an Austrian-German one. Under fire conditions the prEN 1993-1-2 (structural fire design) presents formulae, for the design of beam-columns based on the prENV 1993-1-1 (1992). In order to study the possibility of having, in part 1-1 and part 1-2 of the Eurocode 3, the same approach, a numerical research was made using the finite element program SAFIR, developed at the University of Liege for the study 4 structures subjected to fire. [less ▲]

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See detailLes fondations belges d'utilité publique : entre permanence et changements
Pirotte, Gautier ULg; Heuschen, Laurence

Report (2003)

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See detailSite-directed mutagenesis of conserved inverted repeat sequences in the xylanase C promoter region from Streptomyces sp EC3
Giannotta, F.; Georis, J.; Rigali, Sébastien ULg et al

in Molecular Genetics & Genomics (2003), 270(4), 337-346

Streptomyces sp. EC3, a strain which was originally isolated from cattle manure compost, was shown to possess a strong xylanolytic activity. One of the genes responsible for this activity, xlnC, encodes a ... [more ▼]

Streptomyces sp. EC3, a strain which was originally isolated from cattle manure compost, was shown to possess a strong xylanolytic activity. One of the genes responsible for this activity, xlnC, encodes a secreted xylanase. In the native strain, as in the heterologous host S. lividans, expression of xlnC was detectable in the presence of xylan but not in the presence of glucose. Induction by xylan was shown to take place at the transcriptional level. The transcriptional start site of xlnC was mapped and likely -35 (5'-TTGACA-3') and -10 (5'-GAGAAC-3') motifs were identified. In order to localise putative conserved regulatory sequences, the promoter regions of xylanase-encoding genes from various Streptomyces species were aligned. This alignment revealed the existence of three sets of quite well conserved palindromic AT rich sequences called boxes 1, 2 and 3. Box 3 (5'-CGAAA N TTTCG-3') is the farthest away from the promoter region (150-200 bp). A shorter version of this palindrome (5'-GAAA NN TTTC-3') or (5'-CGAAA-3') constitutes box 1, which is located just upstream of the putative -35 promoter sequence. Box 2, located 5-7 bp upstream of box 1, comprises a shorter palindrome than box 3, with inverted polarity [5'-(G/C)TTTC (N) GAAA(G/C)-3']. The putative regulatory role of the conserved inverted repeats in boxes 2 and 3 in the promoter region of the xlnC gene from Streptomyces sp. EC3, was assessed. These boxes were modified by site-directed mutagenesis, and the mutant promoter regions, as well as the wild-type promoter region, were separately fused to a beta-lactamase reporter gene. Analysis of the expression patterns of these fusions in cultures grown in the presence of glucose, xylan or both carbon sources demonstrated that these motifs were cis -acting negative regulatory elements, each playing a specific role in the regulation of xlnC expression. Box 3 was shown to be critical for the establishment of repression of xlnC expression by glucose, whereas box 2 was shown to play an important role in the induction of xlnC expression by xylan. [less ▲]

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See detailDétermination d'un rendement fromager de laboratoire en relation avec les caractéristiques chimiques de lairs de brebis.
Rondia, P.; Blecker, Christophe ULg; Romnée, Jean-Michel et al

Poster (2003, December)

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See detailImpact du Percussionaire® et de la kinésithérapie respiratoire conventionnelle après chirurgie cardiaque : étude randomisée contrôlée
Kellens, Isabelle ULg; Fraipont, V.; Weber, T. et al

in Réanimation (2003, December), 12(suppl 3), 243

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See detailA capillary action test for the investigation of adhesion in repair technology
Courard, Luc ULg; Degeimbre, Robert ULg

in Canadian Journal of Civil Engineering (2003), 30(6), 1101-1110

When repair material is laid down on a concrete substrate, the porosity of concrete allows it to penetrate the substrate, increasing the probability of physical interactions, and subsequently increasing ... [more ▼]

When repair material is laid down on a concrete substrate, the porosity of concrete allows it to penetrate the substrate, increasing the probability of physical interactions, and subsequently increasing adhesion. Water absorption by immersion or usual capillary action tests do not provide enough information to understand what happens when contact occurs between the concrete substrate and the cement slurries used as a bonding layer. An adaptation of the capillary action test is presented; this is based on a continuous measurement of mass change of the sample. Major differences according to the type of surface preparation are pointed out: absorption rates as well as mass changes are greater for polished concrete substrates than for sandblasted ones. Centrifuged solutions of cement slurries modified with plasticizers and superplasticizers are used for water replacement in the adapted capillary action test. Results clearly show the influence of these admixtures: the greater the adhesion tension, the greater the wetting of the concrete substrate. Determination of these thermodynamic characteristics and performance of an adapted capillary action test provide a better understanding of the mechanisms of interface creation and promotion of adhesion. [less ▲]

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See detailac magnetic behavior of large-grain magnetoresistive La0.78Ca0.22Mn0.90Ox materials
Vanderbemden, Philippe ULg; Vertruyen, Bénédicte ULg; Rulmont, André ULg et al

in Physical Review. B (2003), 68(22), 224418

We report a detailed set of ac magnetic measurements carried out on bulk large grain La-Ca-Mn-O samples extracted from a floating zone method-grown rod. Three samples with La0.78Ca0.22Mn0.90Ox ... [more ▼]

We report a detailed set of ac magnetic measurements carried out on bulk large grain La-Ca-Mn-O samples extracted from a floating zone method-grown rod. Three samples with La0.78Ca0.22Mn0.90Ox stoichiometry but differing in their microstructure were investigated by electrical resistivity and ac susceptibility measurements: (i) a single grain sample, (ii) a sample containing two grains, and (iii) a polycrystalline sample. We show that the superimposition of dc magnetic fields during ac magnetic susceptibility measurements is an efficient way for characterizing the magnetic transition of samples with different microstructures. Whereas both single grain and polycrystalline samples display a single susceptibility peak, an additional kink structure is observed in the case of the double grain sample. The temperature dependence of the ac susceptibility measured with superimposed dc magnetic fields is analyzed in the framework of second-order phase transition ideas. The relations between the critical exponents (beta+gamma ~ 1.5, delta ~ 2.5) are found to be close to those of the mean-field model for all samples. This is attributed to the disordering caused by unoccupied Mn sites. ©2003 The American Physical Society. [less ▲]

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See detailEffects of increased afterload on left ventricular performance and mechanical efficiency are not baroreflex-mediated
Kolh, Philippe ULg; Ghuysen, Alexandre ULg; Tchana-Sato, Vincent ULg et al

in European Journal of Cardio - Thoracic Surgery (2003), 24(6), 912-919

Objective: To assess baroreflex intervention during increase in left ventricular afterload, we compared the effects of aortic banding on the intact cardiovascular system and under hexamethonium infusion ... [more ▼]

Objective: To assess baroreflex intervention during increase in left ventricular afterload, we compared the effects of aortic banding on the intact cardiovascular system and under hexamethonium infusion. Methods: Six open-chest pigs, instrumented for measurement of aortic pressure and flow, left ventricular pressure and volume, were studied under pentobarbital-sufentanil anesthesia. Vascular arterial properties were estimated with a four-element windkessel model. Left ventricular contractility was assessed by the slope of end-systolic pressure-volume relationship. Results: The effects of aortic banding on mechanical aortic properties were unaffected by autonomic nervous system inhibition. However, increase in peripheral arterial vascular resistance and in heart rate were prevented by hexamethonium. Aortic banding increased left ventricular contractility and stroke work. Left ventricular-arterial coupling remained unchanged, but mechanical efficiency was impaired. These ventricular changes were independent of baroreflex integrity. Conclusions: Our results demonstrate that an augmentation in afterload has a composite effect on left ventricular function. Left ventricular performance is increased, as demonstrated by increase in contractility and stroke work, but mechanical efficiency is decreased. These changes are observed independently of baroreflex integrity. Such mechanisms of autoregulation, independent of the autonomic nervous system, are of paramount importance in heart transplant patients. (C) 2003 Elsevier B.V. All fights reserved. [less ▲]

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See detailDoes sustained ERP activity in posterior lexico-semantic processing areas during short-term memory tasks only reflect activated long-term memory?
Majerus, Steve ULg; Van der Linden, Martial ULg; Collette, Fabienne ULg et al

in Behavioral and Brain Sciences (2003), 26(6), 746-747

We challenge Ruchkin et al.'s claim in reducing short-term memory (STM) to the active part of long-term memory (LTM), by showing that their data cannot rule out the possibility that activation of ... [more ▼]

We challenge Ruchkin et al.'s claim in reducing short-term memory (STM) to the active part of long-term memory (LTM), by showing that their data cannot rule out the possibility that activation of posterior brain regions could also reflect the contribution of a verbal STM buffer. [less ▲]

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See detailThe influence of an acid-base-equilibrium on the adsorption behaviour of a weak polyampholyte
Mahltig, Boris; Jérôme, Robert ULg; Stamm, Manfred

in Journal of Polymer Research (2003), 10(4), 219-223

A weak diblock polyampholyte PMAA-b-PDMAEMA, poly(methacrylic acid)-block-poly((dimethylamino)ethyl methacrylate), was investigated as a model system for the influence of an acid-base-equilibrium of a ... [more ▼]

A weak diblock polyampholyte PMAA-b-PDMAEMA, poly(methacrylic acid)-block-poly((dimethylamino)ethyl methacrylate), was investigated as a model system for the influence of an acid-base-equilibrium of a phthalic acid buffer system on the polyelectrolyte adsorption behaviour. The adsorption of polyampholyte from aqueous solution onto silicon surfaces is known to be strongly influenced by the parameters of the polymer solution and the properties of the polyampholyte itself like block ratio or molecular weight. In the case of the investigated polyampholytes, the main parameter with the most significant influence on the adsorption is the pH. The big influence of pH on adsorption results from the charges of the polymer chains and the substrate, which are determined by the pH. Therefore, it should be useful to investigate the influence of a buffer system on the polyampholyte adsorption. On the one hand the buffer system enables to determine the pH of the aqueous polyampholyte solution more precisely. On the other hand the concentrations of different phthalic species like the phthalic acid, the hydrogen phthalate and the phthalate are strongly influenced by pH. These different species were observed to have a strong influence on the adsorption behaviour of the polyampholyte, so the adsorption as function of pH was observed to be also determined by the acid-base-equilibrium of the buffer system. The adsorbed amount of polyampholyte dried after the adsorption process was determined using ellipsometry, while the surface topography of these adsorbed layers were characterized by atomic force microscopy (AFM). [less ▲]

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See detailPreventive assessment and enhancement of power system voltage stability: an integrated approach of thermal and voltage security
Capitanescu, Florin ULg

Doctoral thesis (2003)

This thesis is devoted to the preventive assessment and enhancement of voltage stability and security in electric power systems. However, in the course of deriving all the proposed methods we have paid ... [more ▼]

This thesis is devoted to the preventive assessment and enhancement of voltage stability and security in electric power systems. However, in the course of deriving all the proposed methods we have paid attention to keeping them compatible with the (more traditional) handling of thermal overloads, thereby providing a unified treatment of voltage and thermal security. The approaches presented in this work apply to both deregulated environments and classical, vertically integrated ones. The heart of most methods developed in this thesis is : (i) the derivation of sensitivities indicating the relative efficiency of the various bus injections to restore voltage stability or increase an insufficient voltage security margin, and (ii) the use of these sensitivities in linearized security constraints that can be incorporated to various optimization problems. Using this formulation, we deal with three different problems of interest in preventive security analysis: 1) Congestion management. We propose two optimization-based approaches to manage congestions due to voltage instability and/or thermal overload. The control variables are either power injections (generation rescheduling and load curtailment) or power transactions; 2) Computation of Available Transfer Capabilities (ATCs). We determine the simultaneous ATCs of multiple transactions by means of a single optimization-based computation; 3) evaluation of security margins interval. To face the uncertainty affecting power transfers, we present an optimization-based computation of the minimal and maximal margins under the assumption that individual injections vary within specified bounds. Besides this main theme, the thesis offers additional reflections on the: 1) Filtering of contingencies. We propose a simple and reliable technique to filter out harmless contingencies when computing voltage security margins of a large set of contingencies; 2) Evaluation of reactive reserves with respect to a contingency, an important topic for voltage security reasons as well as within the context of a deregulated market where providing reactive reserves is an ancillary service which should be properly paid. Most of the methods proposed in this thesis were successfully tested on realistic power system models. From a practical viewpoint all the above computations have been coupled to the fast time-domain quasi steady-state simulation used in the ASTRE software developed at the University of Liège. [less ▲]

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See detailHigh intraepithelial expression of estrogen and progesterone receptors in the transformation zone of the uterine cervix
Remoue, Franck; Jacobs, Nathalie ULg; Miot, Valérie et al

in American Journal of Obstetrics and Gynecology (2003), 189(6), 1660-1665

OBJECTIVE: Because sex hormones may be involved in tumor initiation and progression, we analyzed the presence of hormone receptors in the transformation zone of the uterine cervix where the majority of ... [more ▼]

OBJECTIVE: Because sex hormones may be involved in tumor initiation and progression, we analyzed the presence of hormone receptors in the transformation zone of the uterine cervix where the majority of human papillomavirus infections and associated (pre)neoplastic lesions develop. STUDY DESIGN: By using 23 total hysterectomy samples from young women who underwent surgery for noncervical benign uterine disease, we analyzed, by immunohistologic techniques, the in situ expression of estrogen (E-2-R) and progesterone (P-4-R) receptors in the transformation zone and ectocervix of the same women. RESULTS: The expression of estrogen receptors and progesterone receptors is significantly higher in the transformation zone compared with the ectocervix. Immunohistochemical localization indicated that hormone receptor-positive cells are mainly observed in (para)basal and intermediate cell layers in both the transformation zone and ectocervical epithelium. When transformation zone samples were segregated into epithelial tissues with a predominantly mature (7/23 samples) or immature (16/23 samples) squamous metaplasia, only biopsy specimens with immature squamous metaplasia showed a significantly higher density of hormone receptor-positive cells compared with ectocervical epithelium (P < .01). CONCLUSION: Our results suggest that the cervical transformation zone may be at increased risk of the development of cancer because of a high sensitivity to sex hormone regulation. (Am J Obstet Gynecol 2003; 189:1660-5.) [less ▲]

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See detailSegmentation by adaptive prediction and region merging
Van Droogenbroeck, Marc ULg; Talbot, Hugues

in Digital Image Computing Techniques and Applications, Volume II (2003, December)

This paper presents a segmentation technique based on prediction and adaptive region merging. While many techniques for segmentation exist, few of them are suited for the segmentation of natural images ... [more ▼]

This paper presents a segmentation technique based on prediction and adaptive region merging. While many techniques for segmentation exist, few of them are suited for the segmentation of natural images containing regular textures defined on non-rectangular segments. In this paper, we propose a description of regions based on a deconvolution algorithm whose purpose is to remove the influence of the shape on region contents. The decoupling of shape and texture information is achieved either by adapting waveforms to the segment shape, which is a time-consuming task that needs to be repeated for each segment shape, or by the extrapolation of a signal to fit a rectangular window, which is the chosen path. The deconvolution algorithm is the key of a new segmentation technique that uses extrapolation as a prediction of neighbouring regions. When the prediction of a region fits the actual content of a connected region reasonably well, both regions are merged. The segmentation process starts with an over-segmented image. It progressively merges neighbouring regions whose extrapolations fit according to an energy criterion. After each merge, the algorithm updates the values of the merging criterion for regions connected to the merged region pair. It stops when no further gain is achieved in merging regions or when mean values of adjacent regions are too different. Simulation results indicate that, although our technique is tailored for natural images containing periodic signals and flat regions, it is in fact usable for a large set of natural images. [less ▲]

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See detailRight lobe living-related liver transplantation in a Jehovah's Witness
Detry, Olivier ULg; De Roover, Arnaud ULg; Kaba, Abdourahmane ULg et al

in Transplant International (2003), 16(12), 895-896

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See detailStabilization of periodic orbits in a wedge billiard
Sepulchre, Rodolphe ULg; Gerard, Manuel

in Proceedings of the 42nd IEEE Conference on Decision and Control (2003, December)

This paper introduces a stabilization problem for an elementary impact control system in the plane. The rich dynamical properties of the wedge billiard, combined to the relevance of the associated ... [more ▼]

This paper introduces a stabilization problem for an elementary impact control system in the plane. The rich dynamical properties of the wedge billiard, combined to the relevance of the associated stabilization problem for feedback control issues in legged robotics make it a valuable benchmark for energy-based stabilization of impact control systems. [less ▲]

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See detailLa parésie spastique du quadriceps fémoral : Une nouvelle entité clinique chez le veau de race Blanc Bleu Belge.
Touati, Kamal ULg; Müller, Philippe ULg; Gangl M. et al

in Annales de Médecine Vétérinaire (2003), 147

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See detailEtude expérimentale des sons auto-entretenus produits par un jet issu d'un conduit et heurtant une plaque fendue
Billon, Alexis ULg

Doctoral thesis (2003)

The production of self-sustained tones (up to 125 dB) by a low Mach number free plane jet impinging on a slotted plate, known as slot-tone, is experimentally studied. For all geometries of the slot’s edge ... [more ▼]

The production of self-sustained tones (up to 125 dB) by a low Mach number free plane jet impinging on a slotted plate, known as slot-tone, is experimentally studied. For all geometries of the slot’s edge tested, the tones are generated from 6 m/s and when a resonant mode of the duct from which the jet flows out is excited. The Strouhal number associated with the tones fundamental frequency describes stages. These one are linked to the number of vortices present, with vortex pairing possibilities. On the other hand, the frequency domain of the fundamental is defined by the two instability modes of the jet. If the edge of the slot is beveled and if this one is placed backwards to the flow, the tones occurs at a lower speed (3.5 m/s) as soon as the jet becomes turbulent, and the excitation of an acoustic resonator is then not necessary. [less ▲]

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