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See detailBulletin agrométéorologique - Situation au 30 juin 2010
Tychon, Bernard ULiege; Djaby, Bakary ULiege; Denis, Antoine ULiege et al

in Bulletin Agrométéorologique (2010), 8(2), 1-6

A la fin du mois de juin, les conditions météorologiques peuvent être qualifiées de globalement bonnes sur la plus grande partie du territoire belge. De bons rendements sont annoncés sans toutefois ... [more ▼]

A la fin du mois de juin, les conditions météorologiques peuvent être qualifiées de globalement bonnes sur la plus grande partie du territoire belge. De bons rendements sont annoncés sans toutefois atteindre les rendements exceptionnels comme ceux du blé de l’an dernier. Les analyses spatiales dérivées de la télédétection confirment cette tendance favorable tout en indiquant une hétérogénéité importante dans certaines régions du pays qui peut être mise sur le compte de précipitations orageuses localisées. Les conditions climatiques des prochaines semaines seront déterminantes pour conserver tous les bons potentiels de rendement des cultures et éviter que la situation ne se dégrade pour les zones à plus faible potentiel. [less ▲]

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See detailWorking on a Method to Compute Inverse of Genomic Relationship Matrix from Sparse Matrices
Faux, Pierre ULiege; Misztal, Ignacy; Gengler, Nicolas ULiege

Conference (2010, July 12)

Genomic relationships matrix (G) are dense matrices used in genomic prediction of dairy cattle. As the number of genotyped animals will increase, an approximation of the inverse of genomic relationships ... [more ▼]

Genomic relationships matrix (G) are dense matrices used in genomic prediction of dairy cattle. As the number of genotyped animals will increase, an approximation of the inverse of genomic relationships matrix is needed. We have developed a method based on a decomposition of G similar to decomposition of additive relationships matrix A. The method of inversion is tested on a set of simulated data. [less ▲]

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See detailA simulation approach for analyzing genomic data using a package of specific FORTRAN90 functions
Faux, Pierre ULiege; Gengler, Nicolas ULiege

Conference (2010, July 12)

A panel of FORTRAN 90 functions was developed to simulate the distribution of bi-allelic (e.g., SNP) genetic markers along a defined genome and the distribution of their alleles in a given population. The ... [more ▼]

A panel of FORTRAN 90 functions was developed to simulate the distribution of bi-allelic (e.g., SNP) genetic markers along a defined genome and the distribution of their alleles in a given population. The simulation program used 3 parameters, those related to the species studied (number of autosomes, average length of autosomes, average number of crossovers by chromosome), the number of markers and those related to the studied population (pedigree). The simulation proceeds in 3 steps: a) random choice of marker positions and allelic frequencies for the minor allele of each marker (range: 0.05 to 0.475), b) simulation of genotypes of the ancestors in the pedigree based on randomly chosen allelic frequencies and c) planned mating of the ancestors according to the pedigree and according to the average crossover rate as a genetic recombination parameter. The simulation returns a fully-genotyped population. This method is flexible because it can be applied to a wide range of cases (not restricted to a single species) and the FORTRAN functions can be extended and used to simulate phenotypes. It is also realistic, because it performs mating plans and selection of animals based on real pedigrees. Development of this simulation panel was the first step in research around advanced methods to compute and invert genomic relationship matrices. [less ▲]

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See detailLes Silphidae...de nouveaux bio-indicateurs en entomologie forensique?
Dekeirsschieter, Jessica ULiege; Verheggen, François ULiege; Haubruge, Eric ULiege

in VII Conférence Internationale Francophone d'Entomologie: Interactions et Biodiversité (2010, July 09)

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See detailIs there a generalized procedural deficit in children with Specific Language Impairment?
Gabriel, Audrey ULiege; Maillart, Christelle ULiege; Guillaume, Mélody et al

Poster (2010, July 08)

Previous studies (Lum et al., 2009; Tomblin et al., 2007; Ullman & Pierpont, 2005) have suggested that difficulties in the procedural learning system could contribute, in part, to the language ... [more ▼]

Previous studies (Lum et al., 2009; Tomblin et al., 2007; Ullman & Pierpont, 2005) have suggested that difficulties in the procedural learning system could contribute, in part, to the language difficulties observed in children with SLI. However, we have recently shown, with an adapted serial reaction time (SRT) task, that children with SLI are able to learn implicitly non-linguistic regularities (Gabriel et al., submitted). In this research, we wanted to determine whether children with SLI are able to learn an 8-elements probabilistic sequence into which irregularities are inserted. Assessing probabilistic sequence learning in children with SLI should help us to better circumscribe the language difficulties of these children [less ▲]

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See detailSpatial heterogeneity of leaf wetness duration in winter wheat canopy and its influence on plant disease epidemiology
Mahtour, Abdeslam ULiege; El Jarroudi, Moussa ULiege; Giraud et al

in Phytopathology (2010)

Leaf wetness duration (LWD) is an important factor influencing the occurrence of plant disease <br />epidemiology. Despite considerable efforts to determine LWD, little attention has been given to <br ... [more ▼]

Leaf wetness duration (LWD) is an important factor influencing the occurrence of plant disease <br />epidemiology. Despite considerable efforts to determine LWD, little attention has been given to <br />study its variability within the canopy. The objective of this study was to evaluate its <br />spatiotemporal variability in wheat fields in a heterogeneous landscape. The spatiotemporal <br />variability of LWD was evaluated in a site close to Arlon (Belgium) during the period May to July <br />2006 and 2007. LWD measurements were made using a set of flat plate sensors deployed at <br />five different distances from a 18 m high hedge (5, 10, 20, 50, 100 m). Each set of two <br />sensors was placed horizontally close the flag leaf. In addition, we collected the amount of <br />dew water that deposited on rigid epoxy plates placed next to each sensors. Experimental <br />results showed that LWD measurements revealed substantial heterogeneity among sensor <br />positions. LWD is longer for sensors closer to the hedge mainly because of its shadowing <br />effect. 3 to 4 hours of difference was observed between sensors located at 5 m and those <br />located at 100 m, and besides, a significant quantitative difference (p < 0.0001) of dew <br />deposit was observed between area beside hedge and those placed at 100 m. In summary, this <br />study provides new information on how wetness is distributed on wheat leaves according to <br />the distance from a hedge. This leads to local microclimate conditions that will contribute to <br />the disease spatial heterogeneity. [less ▲]

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See detailLife Cycle Assessment of Buildings - a review
Reiter, Sigrid ULiege

in Proceedings of ArcelorMittal International Network in Steel Construction 2010 : Sustainability Workshop (2010, July 07)

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See detailLe manque de variabilité des schémas de construction comme facteur explicatif des difficultés morphosyntaxiques chez les enfants dysphasiques
Leroy, Sandrine ULiege; Moulin, Mélissa; Parisse, Christophe et al

Conference (2010, July 06)

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See detailUne intervention de formation examinée et développée à l’aide d’un cadre conceptuel issu du croisement des approches ergonomiques et psychosociologiques
Burlet, Géraldine; Faulx, Daniel ULiege

Conference (2010, July 06)

La contribution étudie les effets d’une intervention de formation fondée sur l’articulation des cadres conceptuels de la psychologie sociale et du socio-constructivisme, en l’occurrence un « dispositif ... [more ▼]

La contribution étudie les effets d’une intervention de formation fondée sur l’articulation des cadres conceptuels de la psychologie sociale et du socio-constructivisme, en l’occurrence un « dispositif d’immersion structuré » (DIS). L’analyse de l’impact de cette intervention, qui poursuit à la fois des objectifs cognitifs, identitaires et comportementaux, est fondée sur l’analyse thématique et structurale de contenu de 25 entretiens, et montre que le DIS a eu des effets conformes aux objectifs poursuivis par l’intervention, et cela aux trois niveaux : (1) des apprentissages sur les manières de fonctionner et de travailler d’autres services, (2) l’accroissement des comportements de coopération entre services, (3) le développement du sentiment d’appartenance organisationnelle. [less ▲]

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See detailTiO2 thin films (1 µm) with ordered porosity used as high performance photoelectrode in DSSC
Dewalque, Jennifer ULiege; Cloots, Rudi ULiege; Dubreuil, Olivier et al

Poster (2010, July 06)

Mesoporous anatase thin films are very promising materials to act as electrode in dye-sensitized solar cells. Randomly oriented nanocrystalline TiO2 particles are usually used to prepare photoelectrodes ... [more ▼]

Mesoporous anatase thin films are very promising materials to act as electrode in dye-sensitized solar cells. Randomly oriented nanocrystalline TiO2 particles are usually used to prepare photoelectrodes with a thickness of 10-15 µm. Templated-assisted dip-coating techniques are used to obtain thin films with ordered porosity. The use of different templates influences the film porosity in terms of long-range order, percentage of porosity, pore size and pores connectivity. The photovoltaic performances of the samples have been evaluated. Such mesostructured films are compared in terms of photovoltaic performance with TiO2 nanoparticles films, generally used in DSSC. [less ▲]

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See detailAnalysis of simple connections in steel structures subjected to natural fires
Hanus, François ULiege

Doctoral thesis (2010)

Until recently, investigations on the fire resistance of steel joints have been neglected by structural engineers under the arguments that the design resistance of connections at room temperature is ... [more ▼]

Until recently, investigations on the fire resistance of steel joints have been neglected by structural engineers under the arguments that the design resistance of connections at room temperature is usually higher than the resistance of the connected members and that the temperature increases more slowly in the joint zone (high concentration of mass, low exposure to radiative fluxes) than in the adjacent beams and columns. However, brittle failures of connection components have been observed especially during the cooling phase of real fires for two main reasons: the high sensitive and non-reversible character of the resistance of bolts and welds at elevated temperatures and the development of high tensile thrusts. The present thesis is a contribution to the understanding of the thermo-mechanical behaviour of simple connections in steel beam-to-column joints subjected to natural fire conditions, with a special attention to the behaviour of these connections during the cooling phase. The distribution of temperature in joints has been analysed by use of numerical models built in SAFIR software. The simplified methods presently mentioned in the Eurocodes are discussed and new methods, calibrated on the results of numerical simulations, are proposed in the present work to predict the temperature profile in steel beams and joints covered by a flat concrete slab under fire. An existing method aimed at evaluating the distribution of internal forces in restrained steel beams (and by extension, in joints) under natural fire has been analysed in detail. Several modifications have been added in order to improve this method and to extend its field of application. The final version of this analytical method has been implemented and validated against numerical results. An experimental programme aimed at characterising the mechanical behaviour of bolts and welds under heating and subsequent cooling is described in the present thesis. The properties of the tested specimens, the thermal loading applied to these specimens, the test set-ups and the results of the tests are reported in detail. Mechanical models for bolts loaded in tension or in shear have been calibrated on the experimental results. The loss of resistance of bolts and welds due to their non-reversible behaviour under heating and subsequent cooling has been quantified. Finally, a large part of the thesis is dedicated to the development of component-based models representing the action of common simple connections under natural fire conditions and to the analysis of the behaviour of these connections as a part of a sub-structure or large-scale structure. These simple models can be used for parametric analyses because it conciliate a reasonable time of definition of the data, an acceptable time of simulation and a good degree of accuracy of the results. Recommendations for the design of connections have been defined. The ductility of connections has a major influence on the occurrence of connection failures and classes of ductility for connections, dependant of the fire loading, have been defined in this work. [less ▲]

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See detailMicrobiological and physicochemical characteristics of Rwandese traditional beer "ikigage"
Lyumugabe Loshima, François ULiege

in African Journal of Biotechnology (2010), 9(27),

Samples of traditional sorghum beer Ikigage was collected in the southern province of Rwanda and analyzed for microbiological and physico-chemical contents. Ikigage contained total aerobic mesophilic ... [more ▼]

Samples of traditional sorghum beer Ikigage was collected in the southern province of Rwanda and analyzed for microbiological and physico-chemical contents. Ikigage contained total aerobic mesophilic bacteria (33.55 x 106 cfu/ml), yeast (10.15 x 106 cfu/ml), lactic acid bacteria (35.35 x 104 cfu/ml), moulds (4.12 x 104 cfu/ml), E. coli (21.90 x 103 cfu/ml), fecal streptococci (22.50 x 103 cfu/ml), Staphylococcus aureus (16.02 x 103 cfu/ml), total coliform (32.30 x 103 cfu/ml), ethanol, soluble protein, reducing sugars, total acidity, pH and Brix were 2.2% (v/v), 9.2 g/l, 2.3, 1.7%, 3.9 and 11.5 bx, respectively. The yeast was identified by API 20 C test and confirmed by PCR-Sequencing of ITS-5.8S region of rDNA. Seventy yeasts isolated in the samples were found to belong to either Saccharomyces cerevisae, Candida inconspicua, Issatchenkia orientalis, Candida magnolia and Candida humilis. Lactic acid bacteria were identified using the API 50 CHL system. Ten different isolates of lactic acid bacteria belonged exclusively to the genus Lactobacillus: Lactobacillus fermentum, Lactobacillus buchneri, and Lactobacillus sp. The micro-organisms of fecal origin are from the water and the operations postfermentation process. The presence of potential pathogens emphasizes the importance of developing starter cultures with GRAS status for commercialization of ikigage. [less ▲]

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See detailTP3 - Systèmes hyperstatiques
Trif, David Ioan ULiege

Learning material (2010)

Le présent chapitre est composé par des exemples sur l'isostaticité - l'hyperstaticité des systèmes mécaniques.

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See detailAnnular groove phase mask coronagraph in diamond for mid-IR wavelengths: manufacturing assessment and performance analysis
Delacroix, Christian ULiege; Forsberg, P.; Karlsson, M. et al

in Oschmann, J.; Clampin, M.; MacEwen, H. (Eds.) Space Telescopes and Instrumentation 2010: Optical, Infrared, and Millimeter Wave (2010, July 01)

Phase-mask coronagraphs are known to provide high contrast imaging capabilities while preserving a small inner working angle, which allows searching for exoplanets or circumstellar disks with smaller ... [more ▼]

Phase-mask coronagraphs are known to provide high contrast imaging capabilities while preserving a small inner working angle, which allows searching for exoplanets or circumstellar disks with smaller telescopes or at longer wavelengths. The AGPM (Annular Groove Phase Mask, Mawet et al. 2005[SUP]1[/SUP]) is an optical vectorial vortex coronagraph (or vector vortex) induced by a rotationally symmetric subwavelength grating (i.e. with a period smaller than λ/n, λ being the observed wavelength and n the refractive index of the grating substrate). In this paper, we present our first midinfrared AGPM prototypes imprinted on a diamond substrate. We firstly give an extrapolation of the expected coronagraph performances in the N-band (~10 μm), and prospects for down-scaling the technology to the most wanted L-band (~3.5 μm). We then present the manufacturing and measurement results, using diamond-optimized microfabrication techniques such as nano-imprint lithography (NIL) and reactive ion etching (RIE). Finally, the subwavelength grating profile metrology combines surface metrology (scanning electron microscopy, atomic force microscopy, white light interferometry) with diffractometry on an optical polarimetric bench and cross correlation with theoretical simulations using rigorous coupled wave analysis (RCWA). [less ▲]

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See detailThe Spitzer search for the transits of HARPS low-mass planets - I. No transit for the super-Earth HD 40307b
Gillon, Michaël ULiege; Deming, D.; Demory, B *-O et al

in Astronomy and Astrophysics (2010), 518(A25),

We used Spitzer and its IRAC camera to search for the transit of the super-Earth HD 40307b. The hypothesis that the planet transits could not be firmly discarded from our first photometric monitoring of a ... [more ▼]

We used Spitzer and its IRAC camera to search for the transit of the super-Earth HD 40307b. The hypothesis that the planet transits could not be firmly discarded from our first photometric monitoring of a transit window because of the uncertainty coming from the modeling of the photometric baseline. To obtain a firm result, two more transit windows were observed and a global Bayesian analysis of the three IRAC time series and the HARPS radial velocities was performed. Unfortunately, the hypothesis that the planet transited during the observed phase window is firmly rejected, while the probability that the planet does transit but that the eclipse was missed by our observations is nearly negligible (0.26%). [less ▲]

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See detailBehavioural response of southern right whales (Eubalaena australis) to anthropogenic approaches in Bahía San Antonio, Río Negro Argentina
Cammareri, Alejandro; Vermeulen, Els ULiege

in Report to the International Whaling Commission (2010)

The behavioural response of southern right whales (SRWs) to human approaches was studied in Bahia San Antonio, Río Negro Argentina, to obtain essential information for the evaluation of a recent ... [more ▼]

The behavioural response of southern right whales (SRWs) to human approaches was studied in Bahia San Antonio, Río Negro Argentina, to obtain essential information for the evaluation of a recent authorized whale-based tourism and the implementation of accurate regulations and conservation measurements. A total of 50 SRW groups were approached with a small zodiac during the whale-seasons (June-October) of 2008 and 2009, accounting for a total of 39h of behavioural observations. The approaches occurred in a slow and controlled way up to a minimum distance of 100m. A focal animal observation (instantaneous point sample) was used to record three mutual exclusive behavioural states: rest, travel and socializing and/or aerial activity. Groups (chosen ad random) consisted out of solitary animals (0.52), Surface Active Groups (SAG; 0.32) and non-SAGs (0.13). Nevertheless, because of the low amount of data, up to now all behavioural responses were analysed regardless group composition. Results indicated that whales continued travelling during an approach, but doubled their time resting after an approach had finished (22% → 40%) and decreased drastically their time socializing or aerially active (21% → 2%). Although the probability that a whale remained in a social/aerially active behaviour when affected by anthropogenic approaches decreased notably (-22%), no significant effect could be found up to now (Z-test for 2 proportions, p>0.05), probably due to the relative small dataset. Nevertheless, the apparent change in SRW social behaviour requires urgently more detailed information to implement conservation strategies regulating adequately the commercial whale-based tourism in the area. [less ▲]

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See detailWASP-8b: a retrograde transiting planet in a multiple system
Queloz, D.; Anderson, D.; Collier Cameron, A. et al

in Astronomy and Astrophysics (2010), 517

We report the discovery of WASP-8b, a transiting planet of 2.25 ± 0.08 M[SUB]Jup[/SUB] on a strongly inclined eccentric 8.15-day orbit, moving in a retrograde direction to the rotation of its late-G host ... [more ▼]

We report the discovery of WASP-8b, a transiting planet of 2.25 ± 0.08 M[SUB]Jup[/SUB] on a strongly inclined eccentric 8.15-day orbit, moving in a retrograde direction to the rotation of its late-G host star. Evidence is found that the star is in a multiple stellar system with two other companions. The dynamical complexity of the system indicates that it may have experienced secular interactions such as the Kozai mechanism or a formation that differs from the “classical” disc-migration theory. Based on observations made with HARPS spectrograph on the 3.6-m ESO telescope and the EULER Swiss telescope at La Silla Observatory, Chile.Radial velocity data are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A href="http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/517/L1">http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/517/L1</A> [less ▲]

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