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See detailCritical specific stream power in gravel-bed rivers
Petit, François ULg; Gob, Frédéric ULg; Houbrechts, Geoffrey ULg et al

in Geomorphology (2005), 69(1-4), 92-101

Experiments with marked pebbles were carried out on different sized rivers of the Belgian Ardenne (catchment areas varying from less than I km(2) to 2700 km(2)). Specific stream power required to cause ... [more ▼]

Experiments with marked pebbles were carried out on different sized rivers of the Belgian Ardenne (catchment areas varying from less than I km(2) to 2700 km(2)). Specific stream power required to cause bedload movement was evaluated and critical values were obtained. Three types of relationship between critical specific stream power (omega(0)) and grain size (D) were established. The values for coo in the largest river (the Ourthe) were the lowest and were close to the values obtained for mountainous rivers carrying large boulders. In medium sized rivers (catchment area between 40 and 500 km(2)), the critical unit stream power was higher. It is likely that it is due to the bedform's greater resistance. This resistance would use up some of the energy that can cause movement and transport of bedload. The amount of resistance of the bedform can be expressed as bedform shear stress (tau ''), determined by the relationship between grain shear stress (tau'-that determines movement and transport of the bedload) and the total shear stress (tau). This ratio varies between 0.4 and 0.5 in the medium sized rivers, compared to 0.7 in the Ourthe. In headwater streams (less than 20 km(2)), there is greater loss of energy due to bedform resistance (tau'/tau < 0.3). Critical specific stream power is higher in this third type of river than in the other two. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

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See detailSurface effects of active folding, illustrated with examples from the TianShan
Hubert, Aurelia ULg; Suppe, J; Gonzalez-Mieres, J. et al

Conference (2005, July)

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See detailExperience from a large multi-centre expanded access programme (EAP) with gefitinib ('Iressa', ZD1839) as monotherapy in advanced non-small cell lung cancer (NSCLC)
van Puijenbroek, R.; Bosquee, Léon ULg; Tits, G. et al

in Lung Cancer (2005, July), 49(Suppl. 2), 273

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See detailTopology Discovery Using an Address Prefix Based Stopping Rule
Donnet, Benoît ULg; Friedman, Timur

in EUNICE Workshop (2005, July)

Recently, a first step towards a highly distributed IP-level topology discovery tool has been made with the introduction of the Doubletree algorithm. Doubletree is an efficient cooperative algorithm that ... [more ▼]

Recently, a first step towards a highly distributed IP-level topology discovery tool has been made with the introduction of the Doubletree algorithm. Doubletree is an efficient cooperative algorithm that allows the discovery of a large portion of nodes and links in the network while strongly reducing probing redundancy on nodes and destinations as well as the amount of probes sent. In this paper, we propose to reduce more strongly the load on destinations and, more essentially, the communication cost required for the cooperation by introducing a probing stopping rule based on CIDR address prefixes. [less ▲]

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See detailLow-Molecular-Weight Protein Tyrosine Phosphatases of Bacillus subtilis
Musumeci, Lucia ULg; Bongiorni, Cristina; Tautz, Lutz et al

in Journal of Bacteriology (2005), 187(14), 4945-4956

In gram-negative organisms, enzymes belonging to the low-molecular-weight protein tyrosine phosphatase (LMPTP) family are involved in the regulation of important physiological functions, including stress ... [more ▼]

In gram-negative organisms, enzymes belonging to the low-molecular-weight protein tyrosine phosphatase (LMPTP) family are involved in the regulation of important physiological functions, including stress resistance and synthesis of the polysaccharide capsule. LMPTPs have been identified also in gram-positive bacteria, but their functions in these organisms are presently unknown. We cloned two putative LMPTPs from Bacillus subtilis, YfkJ and YwlE, which are highly similar to each other in primary structure as well as to LMPTPs from gram-negative bacteria. When purified from overexpressing Escherichia coli strains, both enzymes were able to dephosphorylate p-nitrophenyl-phosphate and phosphotyrosine-containing substrates in vitro but showed significant differences in kinetic parameters and sensitivity to inhibitors. Transcriptional analyses showed that yfkJ was transcribed at a low level throughout the growth cycle and underwent a σB-dependent transcriptional upregulation in response to ethanol stress. The transcription of ywlE was growth dependent but stress insensitive. Genomic deletion of each phosphatase-encoding gene led to a phenotype of reduced bacterial resistance to ethanol stress, which was more marked in the ywlE deletion strain. Our study suggests that YfkJ and YwlE play roles in B. subtilis stress resistance. [less ▲]

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See detailThe antiangiogenic factor, 16-kDa human prolactin, induces endothelial cell cycle arrest by acting at both the G(0)-G(1) and the G(2)-M phases
Tabruyn, Sébastien ULg; Nguyen, Ngoc-Quynh-Nhu ULg; Cornet, Anne ULg et al

in Molecular Endocrinology (2005), 19(7), 1932-1942

The 16-kDa N-terminal fragment of human prolactin (16K hPRL) is a potent antiangiogenic factor that has been shown to prevent tumor growth in a xenograph mouse model. In this paper we first demonstrate ... [more ▼]

The 16-kDa N-terminal fragment of human prolactin (16K hPRL) is a potent antiangiogenic factor that has been shown to prevent tumor growth in a xenograph mouse model. In this paper we first demonstrate that 16K hPRL inhibits serum-induced DNA synthesis in adult bovine aortic endothelial cells. This inhibition is associated with cell cycle arrest at both the G(0)-G(1) and the G(2)-M phase. Western blot analysis revealed that 16K hPRL strongly decreases levels of cyclin D1 and cyclin B1, but not cyclin E. The effect on cyclin D1 is at least partially transcriptional, because treatment with 16K hPRL both reduces the cyclin D1 mRNA level and down-regulates cyclin D1 promoter activity. This regulation may be due to inhibition of the MAPK pathway, but it is independent of the glycogen synthase kinase-3 beta pathway. Lastly, 16K hPRL induces the expression of negative cell cycle regulators, the cyclin-dependent kinase inhibitors p21(cip1) and p27(kip1). In summary, 16K hPRL inhibits serum-induced proliferation of endothelial cells through combined effects on positive and negative regulators of cell cycle progression. [less ▲]

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See detailOptimization of Surface Utilization Using Heuristic Approaches
Langer, Yves; Bay, Maud ULg; Crama, Yves ULg et al

in Ship Technology Research = Schiffstechnik (2005), 52(3), 141-147

We present a scheduling problem that arises in factories producing large building blocks. This is a three dimensional bin-packing problem with two spatial dimensions and a time dimension. We propose an ... [more ▼]

We present a scheduling problem that arises in factories producing large building blocks. This is a three dimensional bin-packing problem with two spatial dimensions and a time dimension. We propose an algorithm based on the guided local search heuristic of Faroe and al. (Informs Journal of Computing,vol.15, 2003). The algorithm is especially developped to consider real-life issues. Finally the algorithm is applied on an industrial problem and shows excellent performances in speed and quality of the solution. [less ▲]

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See detailEfficacy and morbidity of a novel induction treatment for locally advanced NSCLC
Bosquee, Léon ULg; Rinken, Françoise ULg; Bustin, F. et al

in Lung Cancer (2005, July), 49(Suppl. 2), 78

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See detailDétestation de la mélancolie. Note sur la mémoire et sur l'oubli
Havelange, Carl ULg

in vu d'ici (2005), 19

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See detailCareer end for teachers: Towards a better understanding of stress and early retirement
Hansez, Isabelle ULg; Bertrand, Françoise ULg; De Keyser, Véronique ULg et al

in Travail Humain (Le) (2005), 68(3), 193-223

An increasing number of teachers decide to resign before legal retirement age, leading to significant shortages within the profession. A survey was conducted among teachers working in the city of Liege ... [more ▼]

An increasing number of teachers decide to resign before legal retirement age, leading to significant shortages within the profession. A survey was conducted among teachers working in the city of Liege, Belgium. This aimed to determine what led them to withdraw from their jobs and the degree to which stress contributed to their decisions. Various adjustments were made in favour of elderly workers, such as working time and training. The question of whether these are sufficient to keep them motivated in their job was raised. A questionnaire was developed to try and identify the reasons why teachers resign, their motivations for staying in the job and their expectations in terms of career-end adjustments. The key concepts included in this tool were personal factors, job-related factors (i.e. working conditions, organizational and structural changes and job recognition) and employment-related factors. This questionnaire was combined with a subjective stress measure (MSP-A, Lemyre [less ▲]

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See detailAn XMM-Newton observation of the multiple system HD 167971 (O5-8V+O5-8V+(O81)) and the young open cluster NGC6604
De Becker, Michaël ULg; Rauw, Grégor ULg; Blomme, Ronny et al

in Astronomy and Astrophysics (2005), 437(3), 1029-1046

We discuss the results of two XMM-Newton observations of the open cluster NGC 6604 obtained in April and September 2002. We concentrate mainly on the multiple system HD 167971 (O5- 8V + O5- 8V + (O8I ... [more ▼]

We discuss the results of two XMM-Newton observations of the open cluster NGC 6604 obtained in April and September 2002. We concentrate mainly on the multiple system HD 167971 (O5- 8V + O5- 8V + (O8I)). The soft part of the EPIC spectrum of this system is thermal with typical temperatures of about 2 x 106 to 9 x 106 K. The nature ( thermal vs. non-thermal) of the hard part of the spectrum is not unambiguously revealed by our data. If the emission is thermal, the high temperature of the plasma (similar to 2.3 x 10(7) to 4.6 x 10(7) K) would be typical of what should be expected from a wind-wind interaction zone within a long period binary system. This emission could arise from an interaction between the combined winds of the O5- 8V + O5- 8V close binary system and that of the more distant O8I companion. Assuming instead that the hard part of the spectrum is non-thermal, the photon index would be rather steep (similar to 3). Moreover, a marginal variability between our two XMM-Newton pointings could be attributed to an eclipse of the O5 - 8V + O5 - 8V system. The overall X-ray luminosity points to a significant X-ray luminosity excess of about a factor 4 possibly due to colliding winds. Considering HD 167971 along with several recent X-ray and radio observations, we propose that the simultaneous observation of non-thermal radiation in the X-ray (below 10.0 keV) and radio domains appears rather unlikely. Our investigation of our XMM-Newton data of NGC 6604 reveals a rather sparse distribution of X-ray emitters. Including the two bright non-thermal radio emitters HD 168112 and HD 167971, we present a list of 31 X-ray sources along with the results of the cross-correlation with optical and infrared catalogues. A more complete spectral analysis is presented for the brightest X-ray sources. Some of the members of NGC 6604 present some characteristics suggesting they may be pre-main sequence star candidates. [less ▲]

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See detailInvolvement of both prefrontal and inferior parietal cortex in dual-task performance
Collette, Fabienne ULg; Olivier, L.; Van der Linden, Martial ULg et al

in Cognitive Brain Research (2005), 24(2), 237-251

This PET study explored the neural substrate of both dual-task management and integration task using single tasks that are known not to evoke any prefrontal activation. The paradigm included two simple ... [more ▼]

This PET study explored the neural substrate of both dual-task management and integration task using single tasks that are known not to evoke any prefrontal activation. The paradigm included two simple (visual and auditory) discrimination tasks, a dual task and an integration task (requiring simultaneous visual and auditory discrimination), and baseline tasks (passive viewing and hearing). Data were analyzed using SPM99. As predicted, the comparison of each single task to the baseline task showed no activity in prefrontal areas. The comparison of the dual task to the single tasks demonstrated left-sided foci of activity in the frontal gyrus (BA 9/46, BA 10/47 and BA 6), inferior parietal gyrus (BA 40), and cerebellum. By reference to previous neuroimaging studies, BA 9/46 was associated with the coordinated manipulation of simultaneously presented information, BA 10/47 with selection processes, BA 6 with articulatory rehearsal, and BA 40 with attentional shifting. Globally similar regions were found for the integration task, except that the inferior parietal gyrus was not recruited. These results confirm the hypothesis that the left prefrontal cortex is implicated in dual-task performance. Moreover, the involvement of a parietal area in the dual task is in keeping with the hypothesis that a parieto-frontal network sustains executive functioning. [less ▲]

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See detailThe CINEMA Project: A Video-Based Human-Computer Interaction System for Audio-Visual Immersion
Dardenne, Renaud; Embrechts, Jean-Jacques ULg; Van Droogenbroeck, Marc ULg et al

in ERCIM News (2005), 62

Numerous studies are currently focusing on the modelling of humans and their behavior in 3D environments. The CINEMA project has similar goals but differentiates itself by aiming at enhanced interactions ... [more ▼]

Numerous studies are currently focusing on the modelling of humans and their behavior in 3D environments. The CINEMA project has similar goals but differentiates itself by aiming at enhanced interactions, the creation of mixed reality, and the creation of interactive and reactive acoustical environments. Part of the project consists in gesture recognition of a user, who is given the real-time control of auralization and audio spatialization processes. [less ▲]

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See detailThe Concept of Dominance in EC Competition Law
Petit, Nicolas ULg; Geradin, Damien; Hofer, Paul et al

in GCLC (2005)

The first prong of Article 82 of the EC Treaty, which prohibits abuses of a dominant position, requires, prior to the identification of abusive behaviour, evidence that the firm under scrutiny enjoys a ... [more ▼]

The first prong of Article 82 of the EC Treaty, which prohibits abuses of a dominant position, requires, prior to the identification of abusive behaviour, evidence that the firm under scrutiny enjoys a dominant position. Surprisingly, this issue seems to be sometimes overlooked. Enforcers, practitioners and scholars have recently paid greater attention to the concept of abuse than to the question of dominance when discussing Article 82 EC. This should not, however, be interpreted as a sign that the law of dominance is clear. Quite to the contrary, the concept of dominance raises a wide array of questions which are discussed in the sections that follow [less ▲]

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See detailPrice Discrimination Under Ec Competition Law: Another Antitrust Theory in Search of Limiting Principles
Petit, Nicolas ULg; Geradin, Damien

in GCLC (2005)

Price discrimination is one of the most complex areas of EC competition law. There are several reasons for this. First, the concept of price discrimination covers many different practices (discounts and ... [more ▼]

Price discrimination is one of the most complex areas of EC competition law. There are several reasons for this. First, the concept of price discrimination covers many different practices (discounts and rebates, tying, selective price cuts, discriminatory input prices set by vertically-integrated operators, etc.) whose objectives and effects on competition significantly differ. From the point of view of competition law analysis, it is thus not easy to classify these practices under a coherent analytical framework. Second, there is a consensus among economists that the welfare effects of the (various categories of) price discrimination are ambiguous. It is hard to say a priori whether a given form of price discrimination increases or decreases welfare. The response to this question may indeed depend on which type of welfare standard (total or consumer) is actually pursued. Moreover, even if one agrees on a given standard, the welfare effects of discriminatory prices generally depend on factual issues, such as whether it increases or decreases total output. Third, the exact scope of Article 82(c), the only Treaty provision dealing with discrimination, is not entirely clear. While the European Commission (hereafter, the Commission) and the Community courts have applied Article 82(c) to many different practices, there are good reasons to believe that this provision should be applied to a limited set of circumstances, most forms of discrimination being adequately covered by Article 82(b) or other provisions of the Treaty. Against this background, the main objective of this paper is to throw some light on the compatibility of price discrimination with EC competition law. In order to do so, this paper does not seek to propose a grand unifying theory that would provide a single test offering a way to distinguish between practices compatible and incompatible with the EC Treaty. Instead, we offer an analytical framework which distinguishes between different categories of price discrimination depending on their effects on competition. Different tests may thus be needed to assess the compatibility of the practices belonging to these categories with EC competition law. Another objective of the paper is to show that Article 82(c) should only be applied to the limited circumstances where a non-vertically integrated dominant firm price discriminates between customers with the effect of placing one or several of them at a competitive disadvantage vis-a-vis other customers (secondary line price discrimination). In contrast, Article 82(c) should not be applied to pricing measures designed to harm the dominant firm's competitors (first line price discrimination) or to fragment the single market across national lines. As will be seen, relying on Article 82(c) to condemn such practices goes against the letter and the spirit of this provision and may also apply a wrong test to such practices. It is also not necessary since other Treaty provisions can be used to achieve this objective. [less ▲]

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See detailIn vitro and in vivo evaluation of [I-123]-VEGF(165) as a potential tumor marker
Cornelissen, B.; Oltenfreiter, R.; Kersemans, V. et al

in Nuclear Medicine & Biology (2005), 32(5), 431-436

One of the research challenges in oncology is to develop new biochemical methods for noninvasive tumor therapy evaluation to determine,whether the chemotherapeutics is effective. Vascular endothelial ... [more ▼]

One of the research challenges in oncology is to develop new biochemical methods for noninvasive tumor therapy evaluation to determine,whether the chemotherapeutics is effective. Vascular endothelial growth factor (VEGF) was labeled with radioiodine and evaluated in vitro as well as in vivo, using A2058, a melanoma cell line overexpressing VEGFR-1 and -2. Saturation binding analysis with [I-125]-VEGF resulted in a K-d of 0.1 nM. Internalization assays indicate the preserved ligand induced internalization and metabolization of the tracer. Biodistribution studies with [I-123]-VEGF in wild type and A2058 tumor-bearing athymic mice showed low background activity and a tumor to reference tissue ratio of maximum 6.12. These results suggest that [I-123]-VEGF is a potentially suitable tracer for tumor therapy evaluation. (c) 2005 Elsevier Inc. All rights reserved. [less ▲]

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See detailGCLC Research Papers on Article 82 EC: The concept of dominance
Petit, Nicolas ULg; Geradin, Damien; Hofer, Paul et al

in GCLC College d'Europe (2005)

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See detailGrammaticality judgment in French-speaking children with Specific Language Impairment
Maillart, Christelle ULg; Schelstraete, Marie-Anne

in Journal of Multilingual Communication Disorders (2005), 3(2), 103-109

Grammaticality judgement abilities were examined among French-speaking children with SLI. Rice, Wexler, and Redmond (1999) showed that children’s grammatical judgements paralleled their production: they ... [more ▼]

Grammaticality judgement abilities were examined among French-speaking children with SLI. Rice, Wexler, and Redmond (1999) showed that children’s grammatical judgements paralleled their production: they rejected morphosyntactic errors they were unlikely to commit (e.g., agreement errors), whereas they accepted morphosyntactic errors that they were likely to produce (e.g., violation of tense marking). According to the authors, their findings supported the extended optional infinitive (EOI) account of a morphosyntactic limitation in SLI children based on underlying grammatical representations. They did not support accounts of input processing deficits or production constraints. However, important methodological limitations have challenged their results. In our study, SLI children and their control counterparts were asked to detect different grammatical violations: (1) agreement errors; (2) violations of tense marking; or (3) a control measure: order violations. Contrary to the control children, SLI children appeared to be sensitive to the kind of modification to be detected. They detected significantly fewer verbal morphology-related violations (1 and 2) than order violations (3). These findings, which weaken Rice et al.’s results, are more compatible with other interpretations (e.g., phonological or cognitive) of grammatical disorders in SLI than with an EOI account. [less ▲]

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See detailValidation of a numerical diffusion equation-based modelling of the reverberated sound field in long rooms
Foy, Cédric; Billon, Alexis ULg; Valeau, Vincent et al

Conference (2005, July)

Many applications as corridors, railways tunnels or tube stations present a long room geometry. A fast and reliable modelling of such sound fields could be helpful for designers. In fact, the classical ... [more ▼]

Many applications as corridors, railways tunnels or tube stations present a long room geometry. A fast and reliable modelling of such sound fields could be helpful for designers. In fact, the classical statistical theory based on the assumptions of diffuse sound field is not applicable in such cases because the reverberant sound energy along the room is not uniform. In this study, several models assuming diffuse reflections of sound by walls are used for predicting the reverberant sound field in long rooms. Two models based on a diffusion equation for the energy density (one numerical and one analytical based on an image approach for describing the sound reflection at the corridor extremity) are compared with a radiosity model, and with a ray tracing software. Predictions are compared in terms of sound attenuation and reverberation time with measured data. The long rooms considered in this study were two rectangular corridors of lengths 20.3m and 47.3m. All models overestimate the attenuation, reaching 6dB for the numerical diffusion based model. When a part of specular reflection (30%) is added in the ray tracing model, the predicted sound attenuation matches with the measured one: even in case of rough surfaces, specular reflections cannot be totally excluded. For reverberation time, the agreement between predictions and experiments is good with fewer than 15% of discrepancy. The best predictions of the reverberation time were given by the diffusion models, with discrepancy less than 2% for the numerical model. So, it could be concluded that it is difficult to find a prediction method which is consistent both in terms of steady state and sound decay for the acoustics of long halls. [less ▲]

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