References of "2009"
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See detailFrom subspace learning to distance learning: a geometrical optimization approach
Meyer, Gilles ULg; Journée, Michel; Bonnabel, Silvère et al

in Proceedings of the 2009 IEEE Workshop on Statistical Signal Processing (SSP2009) (2009)

In this paper, we adopt a differential-geometry viewpoint to tackle the problem of learning a distance online. As this prob- lem can be cast into the estimation of a fixed-rank positive semidefinite (PSD ... [more ▼]

In this paper, we adopt a differential-geometry viewpoint to tackle the problem of learning a distance online. As this prob- lem can be cast into the estimation of a fixed-rank positive semidefinite (PSD) matrix, we develop algorithms that ex- ploits the rich geometry structure of the set of fixed-rank PSD matrices. We propose a method which separately updates the subspace of the matrix and its projection onto that subspace. A proper weighting of the two iterations enables to continu- ously interpolate between the problem of learning a subspace and learning a distance when the subspace is fixed. [less ▲]

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See detailCumulate origin and polybaric crystallization of Fe-Ti oxide ores in the Suwalki anorthosite, northeastern Poland
Charlier, Bernard ULg; Namur, Olivier ULg; Duchesne, Jean Clair et al

in Economic Geology (2009), 104

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See detailSocial enviroment influences aphid production of alarm pheromone
Verheggen, François ULg; Haubruge, Eric ULg; De Moraes, Consuelo M et al

in Behavioral Ecology (2009), 20(2), 283-288

In most aphid species, the volatile sesquiterpene (E)-beta-farnesene (E beta f) is released as an alarm pheromone in response to predation and is also emitted continuously at low levels. Some aphid ... [more ▼]

In most aphid species, the volatile sesquiterpene (E)-beta-farnesene (E beta f) is released as an alarm pheromone in response to predation and is also emitted continuously at low levels. Some aphid predators use E beta f as a foraging cue, suggesting that the benefits to aphids of signaling via E beta f must be weighed against the cost of increasing apparency to natural enemies. To determine whether aphids vary E beta f production in response to features of their social environment, we compared the production of E beta f by Acyrthosiphon pisum (Harris) individuals reared in isolation with that of individuals reared among conspecifics or individuals of a different aphid species, Myzus persicae. Production of E beta f by A. pisum reared in isolation was significantly lower than that of aphids reared among conspecifics or among M. persicae individuals. When we reared A. pisum individuals in isolation but exposed them to odors from an aphid colony, E beta f production was similar to that of aphids reared among conspecifics, suggesting that aphids use a volatile cue to assess their social environment and regulate their production of alarm pheromone. It is likely that this cue is E beta f itself, the only volatile compound previously found in headspace collections of A. pisum colonies. Finally, we examined the attraction of a predatory hoverfly, which uses E beta f as a foraging cue, to groups of aphids reared in isolation or among conspecifics and found that groups comprising individuals reared in isolation were significantly less attractive to the predator, suggesting that the observed variation in E beta f production may be ecologically relevant. [less ▲]

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See detailOn the derivation of the Dirac equation
Sartor, Renato ULg

in arXiv: 0903.3828 [quant-ph] (2009)

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See detailStatistical inverse analysis based on genetic algorithm and principal component analysis: Method and developments using synthetic data
Levasseur, Séverine ULg; Malécot, Yann; Boulon, Marc et al

in International Journal for Numerical and Analytical Methods in Geomechanics (2009), 33(12), 1485-1511

This study concerns the identification of parameters of soil constitutive models from geotechnical measurements by inverse analysis. To deal with the non-uniqueness of the solution, the inverse analysis is ... [more ▼]

This study concerns the identification of parameters of soil constitutive models from geotechnical measurements by inverse analysis. To deal with the non-uniqueness of the solution, the inverse analysis is based on a genetic algorithm (GA) optimization process. For a given uncertainty on the measurements, the GA identifies a set of solutions. A statistical method based on a principal component analysis (PCA) is, then, proposed to evaluate the representativeness of this set. It is shown that this representativeness is controlled by the GA population size for which an optimal value can be defined. The PCA also gives a first-order approximation of the solution set of the inverse problem as an ellipsoid. These developments are first made on a synthetic excavation problem and on a pressuremeter test. Some experimental applications are, then, studied in a companion paper, to show the reliability of the method. [less ▲]

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See detailLe Dévonien: des mousses à l'arbre.
Gerrienne, Philippe ULg

Conference (2009)

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See detailRandom matrix model for antiferromagnetism and superconductivity on a two-dimensional lattice
Vanderheyden, Benoît ULg; Jackson, A. D.

in Physical Review B (Condensed Matter and Materials Physics) (2009), 79(14), 144502

We suggest a new mean-field method for studying the thermodynamic competition between magnetic and superconducting phases in a two-dimensional square lattice. A partition function is constructed by ... [more ▼]

We suggest a new mean-field method for studying the thermodynamic competition between magnetic and superconducting phases in a two-dimensional square lattice. A partition function is constructed by writing microscopic interactions that describe the exchange of density and spin fluctuations. A block structure dictated by spin, time-reversal, and bipartite symmetries is imposed on the single-particle Hamiltonian. The detailed dynamics of the interactions are neglected and replaced by a normal distribution of random matrix elements. The resulting partition function can be calculated exactly. The thermodynamic potential has a structure which depends only on the spectrum of quasiparticles propagating in fixed condensation fields, with coupling constants that can be related directly to the variances of the microscopic processes. The resulting phase diagram reveals a fixed number of phase topologies whose realizations depend on a single coupling parameter ratio, alpha. Most phase topologies are realized for a broad range of values of alpha and can thus be considered robust with respect to moderate variations in the detailed description of the underlying interactions. [less ▲]

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See detailApplication of image analysis in food drying
Jinorose, Maturada; Devahastin, Sakamon; Blacher, Silvia ULg et al

in Ratti, C. (Ed.) Advances in Food Dehydration (2009)

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See detailLa fédération canadienne
Fournier, Bernard ULg

in Fournier, Bernard; Reuchamps, Min (Eds.) Le fédéralisme en Belgique et au Canada : comparaison sociopolitique (2009)

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See detailSafety and efficacy of tibolone in breast cancer patients with vasomotor symptoms : a double-blind, randomised non inferiority tria
Kenemans, P.; Bundred, N. J.; Foidart, Jean-Michel ULg et al

in Lancet Oncology (2009), 10(2), 135-46

Background Vasomotor symptoms and bone loss are complications frequently induced by adjuvant treatment for breast cancer. Tibolone prevents both side-effects, but its effect on cancer recurrence is ... [more ▼]

Background Vasomotor symptoms and bone loss are complications frequently induced by adjuvant treatment for breast cancer. Tibolone prevents both side-effects, but its effect on cancer recurrence is unknown. The aim of this study was to show non-inferiority of tibolone to placebo regarding risk of recurrence in breast-cancer patients with climacteric complaints. Methods Between July 11, 2002, and Dec 20, 2004, women surgically treated for a histologically confirmed breast cancer (T1–3N0–2M0) with vasomotor symptoms were randomly assigned to either tibolone 2·5 mg daily or placebo at 245 centres in 31 countries. Randomisation was done by use of a centralised interactive voice response system, stratified by centre, with a block size of four. The primary endpoint was breast-cancer recurrence, including contralateral breast cancer, and was analysed in the intention-to-treat (ITT) and per-protocol populations; the margin for non-inferiority was set as a hazard ratio of 1·278. This study is registered with ClinicalTrials.gov, number NCT00408863. Findings Of the 3148 women randomised, 3098 were included in the ITT analysis (1556 in the tibolone group and 1542 in the placebo group). Mean age at randomisation was 52·7 years (SD 7·3) and mean time since surgery was 2·1 years (SD 1·3). 1792 of 3098 (58%) women were node positive and 2185 of 3098 (71%) were oestrogen-receptor positive. At study entry, 2068 of 3098 (67%) women used tamoxifen and 202 of 3098 (6·5%) women used aromatase inhibitors. The mean daily number of hot flushes was 6·4 (SD 5·1). After a median follow-up of 3·1 years (range 0·01–4·99), 237 of 1556 (15·2%) women on tibolone had a cancer recurrence, compared with 165 of 1542 (10·7%) on placebo (HR 1·40 [95% CI 1·14–1·70]; p=0·001). Results in the per-protocol population were similar (209 of 1254 [16·7%] women in the tibolone group had a recurrence vs 138 of 1213 [11·4%] women in the placebo group; HR 1·44 [95% CI 1·16–1·79]; p=0·0009). Tibolone was not different from placebo with regard to other safety outcomes, such as mortality (72 patients vs 63 patients, respectively), cardiovascular events (14 vs 10, respectively), or gynaecological cancers (10 vs 10, respectively). Vasomotor symptoms and bone-mineral density improved significantly with tibolone, compared with placebo. [less ▲]

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See detailAsthme aigu grave: une affection qui demeure redoutable.
D'Orio, Virginie ULg; Ghuysen, Alexandre ULg; Lambermont, Bernard ULg

in Revue Médicale de Liège (2009), 64(7-8), 377-81

Severe exacerbations of asthma can be life-threatening if not aggressively treated. Despite the publication of therapeutic guidelines developed by experts in this field and people education programs ... [more ▼]

Severe exacerbations of asthma can be life-threatening if not aggressively treated. Despite the publication of therapeutic guidelines developed by experts in this field and people education programs, early recognition and characterization of patients at risk for fatal asthma remain scarce. We report the case of a young lady suffering from acute exacerbation of asthma responsible for intensive care admission with long term mechanical ventilation due to the lack in initial appropriate care. [less ▲]

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See detail"Kadenzen des ganzen Körpers" - Das Sich-Bewegen des Musikers.
Viehöver, Vera ULg; Wunsch, Stephan

in Görling, Reinhold; Skrandies, Timo; Trinkaus, Stephan (Eds.) Geste - Bewegungen zwischen Film und Tanz (2009)

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See detailSaturn's equinoctial auroras
Nichols, J. D.; Badman, S. V.; Bunce, E. J. et al

in Geophysical Research Letters (2009), 36

We present the first images of Saturn's conjugate equinoctial auroras, obtained in early 2009 using the Hubble Space Telescope. We show that the radius of the northern auroral oval is similar to 1.5 ... [more ▼]

We present the first images of Saturn's conjugate equinoctial auroras, obtained in early 2009 using the Hubble Space Telescope. We show that the radius of the northern auroral oval is similar to 1.5 degrees smaller than the southern, indicating that Saturn's polar ionospheric magnetic field, measured for the first time in the ionosphere, is similar to 17% larger in the north than the south. Despite this, the total emitted UV power is on average similar to 17% larger in the north than the south, suggesting that field-aligned currents (FACs) are responsible for the emission. Finally, we show that individual auroral features can exhibit distinct hemispheric asymmetries. These observations will provide important context for Cassini observations as Saturn moves from southern to northern summer. Citation: Nichols, J. D., et al. (2009), Saturn's equinoctial auroras, Geophys. Res. Lett., 36, L24102, doi: 10.1029/2009GL041491. [less ▲]

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See detailSéminaire d'histoire de l'art de l'Epoque contemporaine. Le XXe siècle
Bawin, Julie ULg

Learning material (2009)

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See detailGerminal centre innervation of bovine and human tonsils related to prion diseases.
Defaweux, Valérie ULg; Dorban, Gauthier; Antoine, Nadine ULg et al

in Brain, Behavior & Immunity (2009), 23(1), 10

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See detailThe obese dog and its owner : a method to implement a weight loss program using a concept map
Diez, Marianne ULg; Picavet, Philippe; Istasse, Louis ULg et al

in Mussa, P. P.; Nery, J.; Sciavone, A. (Eds.) et al Congress Proceedings 13t h Congress of the ESVCN (2009)

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