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See detailCombining Coronagraphy with Interferometry as a Tool for Measuring Stellar Diameters
Riaud, P.; Hanot, Charles ULiege

in Astrophysical Journal (2010)

The classical approach for determining stellar angular diameters is to use interferometry and to measure fringe visibilities. Indeed, in the case of a source having a diameter larger than typically λ/6B ... [more ▼]

The classical approach for determining stellar angular diameters is to use interferometry and to measure fringe visibilities. Indeed, in the case of a source having a diameter larger than typically λ/6B, B being the interferometer's baseline and λ the wavelength of observation, the fringe contrast decreases. Similarly, it is possible to perform angular diameter determinations by measuring the stellar leakage from a coronagraphic device or a nulling interferometer. However, all coronagraphic devices (including those using nulling interferometry) are very sensitive to pointing errors and to the size of the source, two factors with significant impact on the rejection efficiency. In this work, we present an innovative idea for measuring stellar diameter variations, combining coronagraphy together with interferometry. We demonstrate that, using coronagraphic nulling statistics, it is possible to measure such variations for angular diameters down to ≈λ/40B with 1σ error-bars as low as ≈λ/1500B. For that purpose, we use a coronagraphic implementation on a two-aperture interferometer, a configuration that significantly increases the precision of stellar diameter measurements. Such a design offers large possibilities regarding the stellar diameter measurement of Cepheids or Mira stars, at a 60-80 μas level. We report on a simulation of a measurement applied to a typical Cepheid case, using the VLTI-UT interferometer on Paranal. [less ▲]

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See detailFirst Orbital Solution for the Non-thermal Emitter Cyg OB2 No. 9
Nazé, Yaël ULiege; Damerdji, Yassine ULiege; Rauw, Grégor ULiege et al

in Astrophysical Journal (2010), 719

After the first detection of its binary nature, the spectroscopic monitoring of the non-thermal radio emitter Cyg OB2 No. 9 (P = 2.4 yr) has continued, doubling the number of available spectra of the star ... [more ▼]

After the first detection of its binary nature, the spectroscopic monitoring of the non-thermal radio emitter Cyg OB2 No. 9 (P = 2.4 yr) has continued, doubling the number of available spectra of the star. Since the discovery paper of 2008, a second periastron passage has occurred in 2009 February. Using a variety of techniques, the radial velocities could be estimated and a first, preliminary orbital solution was derived from the He I 5876 line. The mass ratio appears close to unity and the eccentricity is large, i.e., 0.7-0.75. X-ray data from 2004 and 2007 are also analyzed in quest of peculiarities linked to binarity. The observations reveal neither large overluminosity nor strong hardness, but it must be noted that the high-energy data were taken after the periastron passage, at a time where colliding wind emission may be low. Some unusual X-ray variability is however detected, with a 10% flux decrease between 2004 and 2007. To clarify their origin and find a more obvious signature of the wind-wind collision, additional data, taken at periastron and close to it, are needed. Based on observations collected at the Haute-Provence Observatory and with XMM-Newton, an ESA Science Mission with instruments and contributions directly funded by ESA Member States and the USA (NASA). [less ▲]

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See detailDam-break flow computation based on an efficient flux-vector splitting
Erpicum, Sébastien ULiege; Dewals, Benjamin ULiege; Archambeau, Pierre ULiege et al

in Journal of Computational & Applied Mathematics (2010), 234

Dam-break flow computation is a task of prime interest in the scope of risk analysis processes related to dams and reservoirs. In this paper, a 2D finite volume multiblock flow solver, able to deal with ... [more ▼]

Dam-break flow computation is a task of prime interest in the scope of risk analysis processes related to dams and reservoirs. In this paper, a 2D finite volume multiblock flow solver, able to deal with natural topography variation, is presented in details. The model is based on an efficient Flux Vector Splitting method developed by the authors. A number of validation examples are comprehensively described. [less ▲]

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See detailLas otras traducciones
Willson, Patricia ULiege

Article for general public (2010)

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See detailEarly homeostatic disturbances of human growth and maturation by endocrine disrupters
Bourguignon, Jean-Pierre ULiege; Parent, Anne-Simone ULiege

in Current Opinion in Pediatrics (2010), 22(4), 470-477

We attempt to delineate and integrate aspects of growth and development that could be affected by endocrine disrupters [endocrine-disrupting compounds (EDC)], an increasing public health concern. RECENT ... [more ▼]

We attempt to delineate and integrate aspects of growth and development that could be affected by endocrine disrupters [endocrine-disrupting compounds (EDC)], an increasing public health concern. RECENT FINDINGS: Epidemiological and experimental data substantiate that fetal and early postnatal life are critical periods of exposure to endocrine disrupters, with possible transgenerational effects. The EDC effects include several disorders of the reproductive system throughout life (abnormalities of sexual differentiation, infertility or subfertility and some neoplasia) and disorders of energy balance (obesity and metabolic syndrome). The mechanisms are consistent with the concept of 'developmental origin of adult disease'. They could involve cross-talk between the factors controlling reproduction and those controlling energy balance, both in the hypothalamus and peripherally. SUMMARY: Due to ubiquity of endocrine disrupters and lifelong stakes of early exposure, individual families should be provided by pediatricians with recommendations following the precautionary principle, that is prevention or attenuation of conditions possibly detrimental to health before the evidence of such adverse effects is complete and undisputable. [less ▲]

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See detailThe repressing function of the oncoprotein BCL-3 requires CtBP while its polyubiquitination and degradation involve the E3 ligase TBLR1
Keutgens, Aurore ULiege; Shostak, Kateryna ULiege; Close, Pierre ULiege et al

in Molecular & Cellular Biology (2010), 30

The nuclear and oncogenic BCL-3 protein activates or represses gene transcription when bound to NF-kB proteins p50 and p52, yet the molecules that specifically interact with BCL-3 and drive BCL-3-mediated ... [more ▼]

The nuclear and oncogenic BCL-3 protein activates or represses gene transcription when bound to NF-kB proteins p50 and p52, yet the molecules that specifically interact with BCL-3 and drive BCL-3-mediated effects on gene expression remain largely uncharacterized. Moreover, GSK3-mediated phosphorylation of BCL-3 triggers its degradation through the proteasome, but the proteins involved in this degradative pathway are poorly characterized. Biochemical purification of interacting partners of BCL-3 led to the identification of CtBP as a molecule required for the ability of BCL-3 to repress gene transcription. CtBP is also required for the oncogenic potential of BCL-3 and for its ability to inhibit UV-mediated cell apoptosis in keratinocytes. We also defined the E3 ligase TBLR1 as a protein involved in BCL-3 degradation through a GSK3-independent pathway. Thus, our data demonstrate that the LSD1/CtBP complex is required for the repressing abilities of an oncogenic IkB protein, and they establish a functional link between the E3 ligase TBLR1 and NF-kB. [less ▲]

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See detailThe European Union Export Control Regime: Comment of the Legislation: article-by-article
Michel, Quentin ULiege

Book (2010)

This document analyses and comments article by article the following Regulations, Directives and Joint Actions: Council Regulation (EC) No 428/2009 of 5 May 2009 setting up a Community regime for the ... [more ▼]

This document analyses and comments article by article the following Regulations, Directives and Joint Actions: Council Regulation (EC) No 428/2009 of 5 May 2009 setting up a Community regime for the control of exports, transfer, brokering and transit of dual-use items; Council Joint Action of 22 June 2000 (2000/0401/CFSP) concerning the control of technical assistance related to certain military end-uses; Council Regulation (EC) No 1236/2005 of 27 June 2005 concerning trade in certain goods which could be used for capital punishment, torture or other cruel, inhuman or degrading treatment or punishment; Council Common Position 2008/944/CFSP of December 2008 defining common rules governing control of export of military technology and equipment; Council Common Position 2003/468/CFSP of 23 June 2003 on the control of arms brokering; Council Directive 91/477/EEC of 18 June 1991 on control of the acquisition and possession of weapons. [less ▲]

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See detailInvolvement of odorant cues in the process of superparasitism avoidance
Verheggen, François ULiege; Vandermoten, Sophie ULiege; Frere, Isabelle et al

Poster (2010, August)

The ability to avoid superparasitism provides a selective advantage to parasitoid females, allowing them to avoid depositing eggs in lower quality host. We observed in a Y-olfactometer that generalist ... [more ▼]

The ability to avoid superparasitism provides a selective advantage to parasitoid females, allowing them to avoid depositing eggs in lower quality host. We observed in a Y-olfactometer that generalist aphid parasitoids, Aphidius ervi and Aphidius rhopalosiphi (Hymenoptera, Braconidae), were more attracted toward non-parasitized than parasitized Sitobion avenae (Hemiptera, Aphididae) colonies. We collected the odors released from healthy aphids and aphids parasitized for 2 and 6 days using an electronic nose. Sitobion avenae alarm pheromone, (E)-ß-farnesene (EßF), was the only chemical identified, and was found in lower quantities in parasitized aphids. Both parasitoid species provided pronounced electrical depolarizations to EßF in electroantennography (EAG), and both were attracted to the latter compound in the Y-olfactometer. Parasitoid attraction was known to be guided by a variety of odorant cues released by plants and hosts, and our results support the hypothesis that the aphid alarm pheromone acts as a kairomone for A. ervi and A. rhopalosiphi. [less ▲]

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See detailMilitary Cultures and Education: Harmonizing or Standardizing Europe?
Paile, Sylvain ULiege

in Univers Strategic - Revista Universitara Romana de Studii de Securitate (2010), 2(1), 274

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See detailBayesian Data Fusion for water table interpolation: incorporating a hydrogeological conceptual model in kriging
Peeters, Luk; Fasbender, Dominique; Batelaan, Okke et al

in Water Resources Research (2010), 46(8), 08532

The creation of a contour map of the water table in an unconfined aquifer based on head measurements is often the first step in any hydrogeological study. Geostatistical interpolation methods (e.g ... [more ▼]

The creation of a contour map of the water table in an unconfined aquifer based on head measurements is often the first step in any hydrogeological study. Geostatistical interpolation methods (e.g. kriging) may provide exact interpolated groundwater levels at the measurement locations, but often fail to represent the hydrogeological flow system. A physically based, numerical groundwater model with spatially variable parameters and inputs is more adequate in representing a flow system. Due to the difficulty in parameterization and solving the inverse problem however, an often considerable difference between calculated and observed heads will remain. In this study the water table interpolation methodology presented by Fasbender et al. (2008), in which the results of a kriging interpolation are combined with information from a drainage network and a Digital Elevation Model (DEM), using the Bayesian Data Fusion framework (Bogaert and Fasbender, 2007), is extended to incorporate information from a tuned analytic element groundwater model. The resulting interpolation is exact at the measurement locations while the shape of the head contours is in accordance with the conceptual information incorporated in the groundwater flow model. The Bayesian Data Fusion methodology is applied to a regional, unconfined aquifer in Central Belgium. A cross-validation procedure shows that the predictive capability of the interpolation at unmeasured locations benefits from the Bayesian Data Fusion of the three data sources (kriging, DEM and groundwater model), compared to the individual data sources or any combination of two data sources. [less ▲]

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See detailOn the value of conditioning data to reduce conceptual model uncertainty in groundwater modeling
Rojas, Rodrigo; Feyen, Luc; Batelaan, Okke et al

in Water Resources Research (2010), 46(8), 08520

Recent applications of multi-model methods have demonstrated their potential in quantifying conceptual model uncertainty in groundwater modeling applications. To date, however, little is known about the ... [more ▼]

Recent applications of multi-model methods have demonstrated their potential in quantifying conceptual model uncertainty in groundwater modeling applications. To date, however, little is known about the value of conditioning to constrain the ensemble of conceptualizations, to differentiate among retained alternative conceptualizations, and to reduce conceptual model uncertainty. We address these questions by conditioning multi-model simulations on measurements of hydraulic conductivity and observations of system-state variables and evaluating the e ffects on (i) the posterior multi-model statistics and (ii) the contribution of conceptual model uncertainty to the predictive uncertainty. Multi-model aggregation and conditioning is performed by combining the generalized likelihood uncertainty estimation (GLUE) method and Bayesian model averaging (BMA). As an illustrative example we employ a 3-dimensional hypothetical system under steady-state conditions, for which uncertainty about the conceptualization is expressed by an ensemble (M) of 7 models with varying complexity. Results show that conditioning on heads allowed for the exclusion of the two simplest models, but that their information content is limited to further diff erentiate among the retained conceptualizations. Conditioning on increasing numbers of conductivity measurements allowed for a further reffinement of the ensemble M and resulted in an increased precision and accuracy of the multi-model predictions. For some groundwater flow components not included as conditioning data, however, the gain in accuracy and precision was partially o ffset by strongly deviating predictions of a single conceptualization. Identifying the conceptualization producing the most deviating predictions may guide data collection campaigns aimed at acquiring data to further eliminate such conceptualizations. Including groundwater flow and river discharge observations further allowed for a better diff erentiation among alternative conceptualizations and drastic reductions of the predictive variances. Results strongly advocate the use of observations less commonly available than groundwater heads to reduce conceptual model uncertainty in groundwater modeling. [less ▲]

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See detailLongitudinal effects of muscular hypertrophy allele on milk production traits during the lactation using a novel equivalent model when molecular information is limited
Colinet, Frédéric ULiege; Gengler, Nicolas ULiege

in Proceedings of the 9th World Congress on Genetics Applied to Livestock Production (2010, August)

Given that the mh allele causes the double muscling phenotype, this allele could also influence milk production traits of the dual purpose Belgian Blue cattle. However, all dual purpose Belgian Blue ... [more ▼]

Given that the mh allele causes the double muscling phenotype, this allele could also influence milk production traits of the dual purpose Belgian Blue cattle. However, all dual purpose Belgian Blue animals could not be genotyped. So, a new alternative strategy for the prediction of gene effects and especially their smooth integration into genetic evaluations based on an equivalent method was developed from existing theory. Developed equations were modified to allow that not all animals were genotyped. As expected, the mh allele had negative effects on milk production traits. For the first three lactations, the average estimated allelic substitution effects were -0.074 % fat content and -158.7 kg milk per lactation (305 days). Moreover, effects of mh allele were not constant during the lactation. [less ▲]

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See detailMapping and monitoring issues of a forest soil network in Southern Belgium.
Colinet, Gilles ULiege; Weissen, Frantz; Lecomte, Hugues et al

in Gilkes, R. J.; Prakongkep, N. (Eds.) Proceedings of the 19th World Congress of Soil Science; Soil solutions for a changing world : Brisbane Australia 1-6 August 2010 (2010, August)

Soil monitoring has become a rising concern during last decade in Europe. A Forest Soil Survey (FSS) is being implemented in Southern Belgium as a component of a forest observation and monitoring ... [more ▼]

Soil monitoring has become a rising concern during last decade in Europe. A Forest Soil Survey (FSS) is being implemented in Southern Belgium as a component of a forest observation and monitoring programme. An analysis of the monitoring network has been performed at mid-term of the first investigation stage in order to assess current soil conditions and the temporal evolution that can be detected in the future. The fertility status and the determinism of major and trace elements in forest soils have been investigated at regional scale through uni- and multivariate statistical analyses of the 410 soil samples of the network. A performance analysis of the network has been realized regardings the capacity to detect evolution of soil parameters. The first results show a moderate to strong variability according to the variable considered. High levels of variability were attributed to the presence of carbonated parent material in a distribution largely dominated by detritic terrigeneous rocks. The total contents in forest soils are mainly driven by pedo-geochemical background. The FSS allowed detailed mapping because there are clear convergences between spatial distributions of most of the elements and lithology or small natural regions. The levels of minimum detectable differences (MDD) that can be expected seem only compatible with the monitoring of soil acidification and changes in carbon stocks on the long-term. Future prospects should focus on the improvement of the MDD assessment. [less ▲]

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See detailLongitudinal effects of muscular hypertrophy allele on milk production traits during the lactation using a novel equivalent model when molecular information is limited
Colinet, Frédéric ULiege; Gengler, Nicolas ULiege

Conference (2010, August)

Given that the mh allele causes the double muscling phenotype, this allele could also influence milk production traits of the dual purpose Belgian Blue cattle. However, all dual purpose Belgian Blue ... [more ▼]

Given that the mh allele causes the double muscling phenotype, this allele could also influence milk production traits of the dual purpose Belgian Blue cattle. However, all dual purpose Belgian Blue animals could not be genotyped. So, a new alternative strategy for the prediction of gene effects and especially their smooth integration into genetic evaluations based on an equivalent method was developed from existing theory. Developed equations were modified to allow that not all animals were genotyped. As expected, the mh allele had negative effects on milk production traits. For the first three lactations, the average estimated allelic substitution effects were -0.074 % fat content and -158.7 kg milk per lactation (305 days). Moreover, effects of mh allele were not constant during the lactation. [less ▲]

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See detailGenetic parameters of mastitis-correlated milk components in first parity dairy cows
Gillon, Alain ULiege; Bastin, Catherine ULiege; Soyeurt, Hélène ULiege et al

in Proceedings of the 9th World Congress on Genetics Applied to Livestock Production (2010, August)

Ind. of lactoferrin content, ind. of Na content, and lactose content were the three most correlated milk components with somatic cell score among available milk components predicted by mid-infrared ... [more ▼]

Ind. of lactoferrin content, ind. of Na content, and lactose content were the three most correlated milk components with somatic cell score among available milk components predicted by mid-infrared spectrometry on 590,083 test-day records from Walloon Region of Belgium collected between 2007 and 2009. Mean daily heritabilities and mean genetic correlations of these four traits were estimated using Gibbs sampling methodology applied to a multi-trait random regression test-day model with a subset of these records. Mean daily heritabilities of ind. lactoferrin content (0.34), ind. Na content (0.37) and lactose content (0.42) were higher then SCS (0.16) and mean genetic correlations were moderate (from -0.18 to -0.73), showing that these traits could be used together to describe udder health in genetic evaluations instead of SCS alone when clinical mastitis data are not available. [less ▲]

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See detailAn integrated autonomous protection system against voltage instability based on Load Tap Changers
Vournas, Costas; Lambrou, C.; Glavic, M. et al

in Proceedings of the 2010 IREP Symposium- Bulk Power System Dynamics and Control – VIII (2010, August)

In this paper we propose a local, completely autonomous protection system against voltage instability that can be readily integrated in the controller of each bulk power delivery LTC transformer. The ... [more ▼]

In this paper we propose a local, completely autonomous protection system against voltage instability that can be readily integrated in the controller of each bulk power delivery LTC transformer. The protection system will identify an imminent voltage instability and will subsequently apply the necessary corrective measures to restore stable operation by properly adjusting the distribution voltage setpoint of the LTC. Application of this system on a 52-bus test system showed excellent performance for two unstable cases. For reasons of comparison, the indirect load curtailment proposed in a severe instability case is compared with direct load shedding schemes based on the local detection of instability, as well as on a global detection of instability assuming wide area measurements. [less ▲]

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See detailSans accord négocié, rien ne sera possible : ni la réforme de l'Etat, ni la scission du pays
Behrendt, Christian ULiege

Article for general public (2010)

L'article tend à démontrer qu'il existe, en Belgique, aucune alternative crédible à un dialogue entre les différentes composantes linguistiques du pays, et que cette obligation de dialogue et de décisions ... [more ▼]

L'article tend à démontrer qu'il existe, en Belgique, aucune alternative crédible à un dialogue entre les différentes composantes linguistiques du pays, et que cette obligation de dialogue et de décisions consensuelles vaudrait même dans l'éventualité d'une dislocation de l'Etat ; toute démarche unilatérale paraît se heurter à d'importantes objections de faisabilité pratique. [less ▲]

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See detailAcceleration and gravity power: A concept for understanding total power output
Quievre, Jacques; Cronin, John; Harris, Nigel et al

in Computer Methods in Biomechanics & Biomedical Engineering (2010, August), 13(S1), 113-114

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See detailUnderstanding position transducer technology for strength and conditioning practitioners
Harris, Nigel; Cronin, John; Taylor, Kristie-Lee et al

in Strength & Conditioning Journal (2010), (34), 66-79

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See detailAnalysis of the evolution of the climate parameters, especially precipitations and temperatures, in the province of Binh Thuan in Southern Vietnam based on IPCC models
Doutreloup, Sébastien ULiege; Fettweis, Xavier ULiege; Ozer, Pierre ULiege

Report (2010)

This research is implied into the BELSPO / Vietnamese desertification project and the aim of this work is to analyse the future evolution of the temperatures and precipitations in the region of Binh Thuan ... [more ▼]

This research is implied into the BELSPO / Vietnamese desertification project and the aim of this work is to analyse the future evolution of the temperatures and precipitations in the region of Binh Thuan thanks to the IPCC models (CMIP3). [less ▲]

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