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See detailOn the Sets of Real Numbers Recognized by Finite Automata in Multiple Bases
Boigelot, Bernard ULg; Brusten, Julien ULg; Bruyère, Véronique

in Logical Methods in Computer Science (2010), 6(1), 1-17

This article studies the expressive power of finite automata recognizing sets of real numbers encoded in positional notation. We consider Muller automata as well as the restricted class of weak ... [more ▼]

This article studies the expressive power of finite automata recognizing sets of real numbers encoded in positional notation. We consider Muller automata as well as the restricted class of weak deterministic automata, used as symbolic set representations in actual applications. In previous work, it has been established that the sets of numbers that are recognizable by weak deterministic automata in two bases that do not share the same set of prime factors are exactly those that are definable in the first order additive theory of real and integer numbers. This result extends Cobham's theorem, which characterizes the sets of integer numbers that are recognizable by finite automata in multiple bases. In this article, we first generalize this result to multiplicatively independent bases, which brings it closer to the original statement of Cobham's theorem. Then, we study the sets of reals recognizable by Muller automata in two bases. We show with a counterexample that, in this setting, Cobham's theorem does not generalize to multiplicatively independent bases. Finally, we prove that the sets of reals that are recognizable by Muller automata in two bases that do not share the same set of prime factors are exactly those definable in the first order additive theory of real and integer numbers. These sets are thus also recognizable by weak deterministic automata. This result leads to a precise characterization of the sets of real numbers that are recognizable in multiple bases, and provides a theoretical justification to the use of weak automata as symbolic representations of sets. [less ▲]

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See detailImplicit Real Vector Automata
Boigelot, Bernard ULg; Brusten, Julien ULg; Degbomont, Jean-François ULg

in Electronic Proceedings in Theoretical Computer Science [=EPTCS] (2010), 39

This paper addresses the symbolic representation of non-convex real polyhedra, i.e., sets of real vectors satisfying arbitrary Boolean combinations of linear constraints. We develop an original data ... [more ▼]

This paper addresses the symbolic representation of non-convex real polyhedra, i.e., sets of real vectors satisfying arbitrary Boolean combinations of linear constraints. We develop an original data structure for representing such sets, based on an implicit and concise encoding of a known structure, the Real Vector Automaton. The resulting formalism provides a canonical representation of polyhedra, is closed under Boolean operators, and admits an efficient decision procedure for testing the membership of a vector. [less ▲]

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See detailSemantic Hyperpriming in Normal Aging: A Consequence of Instructions?
Stefaniak, Nicolas ULg; Meulemans, Thierry ULg; Willems, Sylvie ULg

in Neuropsychology, Development, and Cognition. Section B, Aging, Neuropsychology and Cognition (2010), 17(5), 615-632

Semantic hyperpriming has consistently been found in normal aging. However, <br />because the standard instructions to test semantic priming are generally ambiguous <br />(focusing on both accuracy and ... [more ▼]

Semantic hyperpriming has consistently been found in normal aging. However, <br />because the standard instructions to test semantic priming are generally ambiguous <br />(focusing on both accuracy and speed), it is difficult to account for hyperpriming in <br />older adults. By using the direct and mediated priming paradigms, this study investigates <br />whether older adults’ response mode at testing may explain hyperpriming. First, we <br />show that, under identical conditions, inducing a response mode that favors speed leads <br />to greater priming effects in older adults. The pattern of results is similar to what is <br />observed under standard instructions. Second, prompting a response mode that favors <br />accuracy leads to greater priming effects in younger adults. We discuss various explanations <br />for these findings and conclude, in accordance with the Ratcliff, Thapar, <br />Gomez, and McKoon (2004a) diffusion model, that hyperpriming in normal aging is <br />contingent on older adults’ response mode at testing. [less ▲]

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See detailIntegrated control of crown rot of banana with Candida oleophila strain O, calcium chloride and modified atmosphere packaging
Bastiaanse, H.; de Lapeyre de Bellaire, Luc; Lassois, Ludivine ULg et al

in Biological Control (2010), 53

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See detailSoluble forms of VEGF receptor-1 and -2 promote vascular maturation via mural cell recruitment.
LORQUET, Sophie ULg; Berndt, Sarah; Blacher, Silvia ULg et al

in FASEB Journal (2010), 24(10), 3782-95

Two soluble forms of vascular endothelial growth factor (VEGF) receptors, sVEGFR-1 and sVEGFR-2, are physiologically released and overproduced in some pathologies. They are known to act as anti-VEGF ... [more ▼]

Two soluble forms of vascular endothelial growth factor (VEGF) receptors, sVEGFR-1 and sVEGFR-2, are physiologically released and overproduced in some pathologies. They are known to act as anti-VEGF agents. Here, we report that these soluble receptors contribute to vessel maturation by mediating a dialogue between endothelial cells (EC) and mural cells that leads to blood vessel stabilization. Through a multidisciplinary approach, we provide evidences that these soluble VEGF receptors promote mural cell migration through a paracrine mechanism involving interplay in EC between VEGF/VEGFR-2 and sphingosine-1- phosphate type-1 (S1P)/S1P1 pathways that leads to endothelial nitric oxyde synthase (eNOS) activation. This new paradigm is supported by the finding that sVEGFR-1 and -2: 1) induce an eNOS-dependent outgrowth of a mural cell network in an ex vivo model of angiogenesis, 2) increase the mural cell coverage of neovessels in vitro and in vivo, 3) promote mural cell migration towards EC, 4) stimulate endothelial S1P1 overproduction and eNOS activation that promote the migration and the recruitment of neighboring mural cells. These findings provide new insights into mechanisms regulating physiological and pathological angiogenesis and vessel stabilization. [less ▲]

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See detailReliable hydraulic numerical modeling with multiblock grids and linked models
Erpicum, Sébastien ULg; Archambeau, Pierre ULg; Dewals, Benjamin ULg et al

in Proc. Int. Conf. SimHydro 2010: Hydraulic modeling and uncertainty (2010)

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See detailContribution théorique et numérique a la modélisation des écoulements mixtes diphasiques hautement transitoires
Kerger, François ULg; Archambeau, Pierre ULg; Dewals, Benjamin ULg et al

in Proc. Int. Conf. SimHydro 2010: Hydraulic modeling and uncertainty (2010)

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See detailSHIP-1 inhibits CD95/APO-1/Fas-induced apoptosis in primary T lymphocytes and T leukemic cells by promoting CD95 glycosylation independently of its phosphatase activity
Charlier, Edith ULg; Condé, Claude ULg; Zhang, Jing et al

in Leukemia : Official Journal of the Leukemia Society of America, Leukemia Research Fund, U.K (2010)

SHIP-1 functions as a negative regulator of immune responses by hydrolyzing phosphatidylinositol-3,4,5-triphosphate generated by PI 3-kinase activity. As a result, SHIP-1 deficiency in mice results in ... [more ▼]

SHIP-1 functions as a negative regulator of immune responses by hydrolyzing phosphatidylinositol-3,4,5-triphosphate generated by PI 3-kinase activity. As a result, SHIP-1 deficiency in mice results in myeloproliferation and B cell lymphoma. On the other hand, SHIP-1 deficient mice have a reduced T cell population, but the underlying mechanisms are unknown. In this work, we hypothesized that SHIP-1 plays anti-apoptotic functions in T cells upon stimulation of the death receptor CD95/APO-1/Fas. Using primary T cells from SHIP-1-/- mice and T leukemic cell lines, we report here that SHIP-1 is a potent inhibitor of CD95-induced death. We observed that a small fraction of the SHIP-1 pool is localized to the endoplasmic reticulum where it promotes CD95 glycosylation. This post-translational modification requires an intact SH2 domain of SHIP-1, but is independent of its phosphatase activity. The glycosylated CD95 fails to oligomerize upon stimulation, resulting in impaired DISC formation and downstream apoptotic cascade. These results uncover an unanticipated inhibitory function for SHIP-1 and emphasize the role of glycosylation in the regulation of CD95 signaling in T cells. This work may also provide a new basis for therapeutic strategies using compounds inducing apoptosis through the CD95 pathway on SHIP-1 negative leukemic T cells. [less ▲]

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See detailChapter 6 : Agrometeorological forecasting
Gommes, René; Das, Haripada; Mariani, Luigi et al

in WMO/CAgM Guide to Agricultural Meteorological Practices (GAMP) WMO n° 134 (2010)

This chapter presents a set of tools and techniques for crop yield forecasting.

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See detailNational Forest Inventories Pathways for Common Reporting: Belgium (Walloon Region)
Rondeux, Jacques ULg; Sanchez, Christine; Latte, Nicolas ULg

in Tomppo, Erkki; Gschwantner, Thomas; Lawrence, Mark (Eds.) et al National Forest Inventories. Pathways for Common Reporting (2010)

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See detailModave/Modave : elements du Mésolithique recent de la couche 4b-delta du Trou Al'Wesse
Miller, Rebecca ULg; Otte, Marcel ULg; Stewart, John

in Chronique de l'Archéologie Wallonne (2010), 17

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See detailEffect of exogenous circulating anti-bPL antibodies on bovine placental lactogen measurements in foetal samples.
Alvarez Oxiley, Andrea Vivian ULg; Melo de Sousa, Noelita ULg; Hornick, Jean-Luc ULg et al

in Acta Veterinaria Scandinavica (2010), 52

BACKGROUND: The involvement of placental lactogen (PL) in the regulation of foetal growth has been investigated in different species by in vivo immunomodulation techniques. However, when circulating ... [more ▼]

BACKGROUND: The involvement of placental lactogen (PL) in the regulation of foetal growth has been investigated in different species by in vivo immunomodulation techniques. However, when circulating antibodies are present together with the hormone, the procedure for hormonal measurement becomes considerably complex. The aim of this study was the immunoneutralization of bovine placental lactogen (bPL) concentrations in bovine foetal circulation by direct infusion of rabbit anti-bPL purified immunoglobulins (IgG) via a foetal catheter (in vivo study). The ability of a RIA based on guinea pig anti-bPL antiserum, for the measurement of bPL concentrations in samples containing exogenous rabbit anti-bPL immunoglobulins, was also analyzed in in vitro and in vivo conditions. METHODS: Six bovine foetuses were chronic cannulated on the aorta via the medial tarsal artery. Infusion of rabbit anti-bPL IgG was performed during late gestation. Pooled rabbit anti-bPL antisera had a maximal neutralization capacity of 25 microg bPL/mL of immunoglobulin. Interference of rabbit anti-bPL immunoglobulin with radioimmunoassay measurement using guinea pig anti-bPL as primary antibody was first evaluated in vitro. Polyclonal anti-bPL antibodies raised in rabbit were added in foetal sera to produce 100 samples with known antibodies titers (dilutions ranging from 1:2,500 till 1:1,280,000). RESULT(S): Assessment of the interference of rabbit anti-bPL antibody showed that bPL concentrations were significantly lower (P < 0.05) in samples added with dilutions of rabbit antiserum lower than 1:80,000 (one foetus) or 1:10,000 (four foetuses). It was also shown that the recovery of added bPL (12 ng/mL) was markedly reduced in those samples in which exogenous rabbit anti-bPL were added at dilutions lower than 1:20,000. Concentrations of foetal bPL were determined in samples from cannulated foetuses. In foetuses 1 and 6, bPL concentrations remained almost unchanged (<5 ng/mL) during the whole experimental period. In Foetus 3, bPL concentrations decreased immediately after IgG infusion and thereafter, they increased until parturition. CONCLUSION(S): The use of a bPL RIA using a guinea pig anti-bPL as primary antiserum allowed for the measurement of bPL concentrations in foetal plasma in presence of rabbit anti-bPL IgG into the foetal circulation. Long-term foetal catheterization allowed for the study of the influence of direct infusion of anti-bPL IgG on peripheral bPL concentrations in bovine foetuses. [less ▲]

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See detailContractile reserve assessed using dobutamine echocardiography predicts left ventricular reverse remodeling after cardiac resynchronization therapy: prospective validation in patients with left ventricular dyssynchrony.
Sénéchal, Mario; Lancellotti, Patrizio ULg; Magne, Julien ULg et al

in Echocardiography (2010), 27(6), 668-76

Background: The presence of viable myocardium may predict response to cardiac resynchronization therapy (CRT). The aim of this study is to evaluate in patients with left ventricular (LV) dyssynchrony ... [more ▼]

Background: The presence of viable myocardium may predict response to cardiac resynchronization therapy (CRT). The aim of this study is to evaluate in patients with left ventricular (LV) dyssynchrony whether response to CRT is related to myocardial viability in the region of the pacing lead. Methods: Forty-nine consecutive patients with advanced heart failure, LV ejection fraction < 35%, QRS duration > 120 ms and intraventricular asynchronism ≥ 50 ms were included. Dobutamine stress echocardiography was performed within the week before CRT implantation. Resting echocardiography was performed 6 months after CRT implantation. Viability in the region of LV pacing lead was defined as the presence of viability in two contiguous segments. Response to CRT was defined by evidence of reverse LV remodeling (≥15% reduction in LV end-systolic volume). Results: Thirty-one patients (63%) were identified as responders at follow-up. The average of viable segments was 5.9 ± 2 in responders and 3.2 ± 3 in nonresponders (P = 0.0003). Viability in the region of the pacing lead had a sensitivity of 94%, a specificity of 67%, a positive predictive value of 83%, and a negative predictive value of 86% for the prediction of response to CRT. Conclusions: In patients with LV dyssynchrony, reverse remodeling after CRT requires viability in the region of the pacing lead. This simple method using echocardiography dobutamine for the evaluation of local viability (i.e., viability in two contiguous segments) may be useful to the clinician in choosing the best LV lead positioning. [less ▲]

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See detailHydroCube: a new entity-relationship hydrogeological data model
Wojda, Piotr; Brouyère, Serge ULg; Derouane, Johan et al

in Hydrogeology Journal (2010), 18(8), 1953-1962

Managing, handling, and accessing hydrogeological information depend mainly on the applied hydrogeological data models, which differ between institutions and across countries. Growing interest in ... [more ▼]

Managing, handling, and accessing hydrogeological information depend mainly on the applied hydrogeological data models, which differ between institutions and across countries. Growing interest in hydrogeological information diffusion, combined with a need for information availability, require the convergence of hydrogeological data models to make hydrogeological information accessible to multiple users such as universities, administrations, water suppliers, and research organisations. Furthermore, because hydrogeological studies are complex, they require a large variety of high-quality hydrogeological data with appropriate metadata in clearly designed and coherent structures. A need therefore exist to develop and implement hydrogeological data models that cover, as much as possible, the full hydrogeological domain. To respond to these requirements, a new data model, called HydroCube, has been developed for the Walloon Region in Belgium. The HydroCube model presents an innovative holistic “project-based” approach, which covers a full set of hydrogeological concepts and features, allowing for effective hydrogeological project management. This approach enables to store data about the project localisation, hydrogeological equipment, related observations and measurements. In particular, the model focuses on specialized hydrogeological field experiments, such as pumping and tracer tests. This logical data model uses entity-relationship diagrams and it has been implemented in the MS Access environment as the HydroCube database. It has been additionally enriched with a fully functional user-interface. [less ▲]

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See detailNew Biological Investigations on 3-Bromophenyl 6-Acetoxymethyl-2-oxo-2H-1-Benzopyran-3-Carboxylate as Anti-angiogenic Agent
Hemmer, M.; Kempen, Isabelle; De Tullio, Pascal ULg et al

in Drug Development Research (2010), 71

The development of blood vessels inside tumors is required to provide the nutrients and oxygen needed for tumor growth and to allow the spread of cancer cells at a distance to form metastasis ... [more ▼]

The development of blood vessels inside tumors is required to provide the nutrients and oxygen needed for tumor growth and to allow the spread of cancer cells at a distance to form metastasis. Angiogenesis is also implicated in ocular diseases like age-related macular degeneration. The present work describes the potential anti-angiogenic properties of a coumarinic derivative, 3-bromophenyl 6-acetoxymethyl-2-oxo-2H-1-benzopyran-3-carboxylate (IK9), previously described as a potent inhibitor of HT 1080 fibrosarcoma cell invasion in vitro and tumor growth in vivo. In vivo, ex vivo, and in vitro models were used to delineate the anti-angiogenic properties of IK9. The anti-angiogenic effect of IK9 was demonstrated in vivo in a choroidal neovascularization mice model and additionally ex vivo in a rat aortic ring assay where it was more active than the known matrix metalloproteinase inhibitor Ro 28-2653. IK9 did not affect apoptosis, proliferation, or endothelial cell invasiveness in vitro. These findings suggest a complex mechanism of action of the compound via direct or indirect effects on endothelial cell properties. This study identifies IK9 as a new potent inhibitor of angiogenesis and suggests its potential use as a therapeutic agent. [less ▲]

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See detailLe tabac et ses effets sur le système endocrinien
VALDES SOCIN, Hernan Gonzalo ULg; VROONEN, Laurent ULg; Latta, A. et al

in Revue Médicale de Liège (2010), 65(9), 498-501

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See detailEffects of HPV-16 E5, E6 and E7 Proteins on Survival, Adhesion, Migration and Invasion of Trophoblastic Cells
Boulenouar, S.; Weyn, C.; Van Noppen, M. et al

in Carcinogenesis (2010), 31(3), 473-80

Amongst high-risk human papillomaviruses (HPV), HPV-16 infection is the most prevalent causative factor for cervical cancer. Beside other mucosal targets, HPV-16 was reported to infect the placenta and to ... [more ▼]

Amongst high-risk human papillomaviruses (HPV), HPV-16 infection is the most prevalent causative factor for cervical cancer. Beside other mucosal targets, HPV-16 was reported to infect the placenta and to replicate in trophoblastic cells. Since these cells share invasive properties of tumoral cells, they represent an ideal model to investigate several oncogenic processes. In the present work, we analyzed the impacts of HPV-16 E5, E6 and E7 oncoproteins on the trophoblastic model. Our results showed that E5 impaired the viability of trophoblastic and cervical cell lines but E6 and E7, favouring cell growth, neutralised the E5 cytotoxic effect. In addition, E5 decreased the adhesiveness of trophoblastic cells to the tissue culture plastic and to endometrial cells similarly as previously described for E6 and E7. E5 and E6 plus E7 increased also their migration and their invasive properties. Cells expressing HPV-16 early proteins under the control of the LCR endogenous promoter displayed growth advantage and were also more motile and invasive compared to control cells. Interestingly, the E-cadherin was down regulated in trophoblastic cells expressing E5, E6 and E7. NF-kB and AP-1 activities were also enhanced. In conclusion, HPV-16 early proteins enhanced trophoblastic growth and intensify the malignant phenotype by impairing cell adhesion leading to increased cellular motile and invasive properties. HPV-16 E5 participated, with E6 and E7, in these changes by impairing Ecadherin expression, a hallmark of malignant progression. [less ▲]

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See detailInsight on variables leading to burnout in cancer physicians
Bragard, Isabelle ULg; Libert, Y.; Etienne, Anne-Marie ULg et al

in Journal of Cancer Education : The Official Journal of the American Association for Cancer Education (2010), 25

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See detailApplication of multiple-point geostatistics on modelling groundwater flow and transport in a cross-bedded aquifer
Huysmans, Marijke; Dassargues, Alain ULg

in Atkinson, P. M. M.; Lloyd, C. D. D. (Eds.) GeoENV VII – Geostatistics for Environmental Applications, Quantitative Geology and Geostatistics (2010)

In this work, the problem of modelling groundwater flow and transport in a heterogeneous environment with complex geological structures is addressed. This study demonstrates how a training image can be ... [more ▼]

In this work, the problem of modelling groundwater flow and transport in a heterogeneous environment with complex geological structures is addressed. This study demonstrates how a training image can be constructed based on geological and hydrogeological field data and how multiple-point geostatistics can be applied to determine the impact of complex geological heterogeneity on groundwater flow and transport in a real aquifer. [less ▲]

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See detailLe bananier: comment obtenir du matériel de plantation indemne de virus
De Clerck, Caroline ULg; Lassois, Ludivine ULg

Diverse speeche and writing (2010)

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