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See detailNew issues for the Goodness-of-fit test of the error distribution : a comparison between Sinh-arscinh and Generalized Hyperbolic distribution
Hambuckers, julien ULg; Heuchenne, Cédric ULg

Scientific conference (2013, April 30)

In this article, we consider a multiplicative heteroskedastic structure of financial returns and propose a methodology to study the goodness-of-fit of the error distribution. We use non-conventional ... [more ▼]

In this article, we consider a multiplicative heteroskedastic structure of financial returns and propose a methodology to study the goodness-of-fit of the error distribution. We use non-conventional estimation and model selection procedures (Berk-Jones (1978) tests, Sarno and Valente (2004) hypothesis testing, Diks et al. (2011) weighting method), based on the local volatility estimator of Mercurio and Spokoiny (2004) and the bootstrap methodology to compare the fit performances of candidate density functions. In particular, we introduce the sinh-arcsinh distributions (Jones and Pewsey, 2009) and we show that this family of density functions provides better bootstrap IMSE and better weighted Kullback-Leibler distances. [less ▲]

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See detailA new iterative approach to the corrective security-constrained optimal power flow problem
Capitanescu, Florin ULg; Wehenkel, Louis ULg

in IEEE Transactions on Power Systems (2008), 23(4), 1342-1351

This paper deals with techniques to solve the corrective security-constrained optimal power flow (CSCOPF) problem. To this end, we propose a new iterative approach that comprises four modules: a CSCOPF ... [more ▼]

This paper deals with techniques to solve the corrective security-constrained optimal power flow (CSCOPF) problem. To this end, we propose a new iterative approach that comprises four modules: a CSCOPF which considers only a subset of potentially binding contingencies among the postulated ones, a (steady-state) security analysis (SSSA), a contingency filtering (CF) technique, and an OPF variant to check post-contingency state feasibility when taking into account post-contingency corrective actions. We compare performances of our approach and its possible variants with classical CSCOPF approaches such as the direct approach and Benders decomposition (BD), on three systems of 60, 118, and 1203 buses. [less ▲]

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See detailA new jump edge detection method for 3D cameras
Lejeune, Antoine ULg; Pierard, Sébastien ULg; Van Droogenbroeck, Marc ULg et al

in International Conference on 3D Imaging (IC3D) (2011, December)

Edges is a fundamental clue for analyzing, interpreting, and understanding 3D scenes: they describe objects boundaries. Available edge detection methods are not suited for 3D cameras such as the Microsoft ... [more ▼]

Edges is a fundamental clue for analyzing, interpreting, and understanding 3D scenes: they describe objects boundaries. Available edge detection methods are not suited for 3D cameras such as the Microsoft Kinect or a time-of-flight camera: they are slow and do not take into consideration the characteristics of the cameras. In this paper, we present a fast jump edge detection technique for 3D cameras based on the principles of Canny’s edge detector. We first analyze the characteristics of the range signal for two different kinds of cameras: a time-of-flight camera (the PMD[vision] CamCube) and the Microsoft Kinect. From this analysis, we define appropriate operators and thresholds to perform the edge detection. Then, we present some results of the developed algorithms for both cameras. [less ▲]

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See detailNew karyotypic data for Asian rodents (Rodentia, Muridae) with the first report of B-chromosomes in the genus Mus
Badenhorst, Daleen; Herbreteau, Vincent; Chaval, Yannick et al

in Journal of Zoology (2009), 279(1), 44-56

Karyotypes of 18 rodent species collected in various localities in Thailand were analysed as part of an epidemiological survey of the region using conventional cytogenetic techniques. The aim was to re ... [more ▼]

Karyotypes of 18 rodent species collected in various localities in Thailand were analysed as part of an epidemiological survey of the region using conventional cytogenetic techniques. The aim was to re-assess the reliability of karyotype-based diagnoses of Thai rodents using an updated taxonomic framework. The species examined include Menetes berdmorei (Sciuridae), Mus caroli, Mus cervicolor and Mus cookii, Hapalomys delacouri, Chiropodomys gliroides, as well as several representatives of most of the lineages of the Rattini tribe, that is Rattus exulans, Rattus losea, Rattus tanezumi, Leopoldamys edwardsi, Leopoldamys neilli, Maxomys surifer, Niviventer fulvescens, Berylmys berdmorei, Berylmys bowersi, Bandicota indica and Bandicota savilei (Muridae). The first descriptions of G- and/or C-banding karyotypes are provided for several of these, that is, B. savilei, L. edwardsi, M. surifer, B. berdmorei, B. bowersi, N. fulvescens and H. delacouri. Although largely in agreement with available data, our findings on chromosome morphology differ slightly from those published for L. edwardsi, M. surifer, B. savilei and the two Berylmys species, B. berdmorei and B. bowersi. In addition, we document the novel finding of B-chromosomes in the genera Berylmys, Bandicota and the emblematic Mus. Importantly, few species-specific chromosomal characteristic could be identified within most of the genera investigated in our study and, in contrast to previous claims, the usefulness of karyotypes for diagnosing these Asian murid species appears to be limited. [less ▲]

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See detailNew Kids on the Blogs
Dejasse, Erwin ULg; Paques, Frédéric ULg

in Neuvième art 2.0. (2007), 13

The article deals with of the phenomenon of Comic Blogs

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See detailNew learning in dementia
Bier, Nathalie; Adam, Stéphane ULg; Meulemans, Thierry ULg

in Seel, Robert (Ed.) Encyclopedia of the Sciences of Learning (2012)

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See detailNew learning in dementia: transfer and spontaneous use of learning in everyday life functioning. Two case studies.
Bier, Nathalie; Provencher, Veronique; Gagnon, Lise et al

in Neuropsychological Rehabilitation (2008), 18(2), 204-35

The purpose of these two case studies was to explore the effectiveness of learning methods in dementia when applied in real-life settings and the integration of new skills in daily life functioning. The ... [more ▼]

The purpose of these two case studies was to explore the effectiveness of learning methods in dementia when applied in real-life settings and the integration of new skills in daily life functioning. The first participant, DD, learned to look at a calendar with the spaced retrieval method to answer his repeated questions about the current date and calls made to family. Progressive cuing was used by his wife to increase spontaneous use of the calendar, but DD had difficulty integrating the calendar into his routine. The second patient, MD, relearned a leisure activity (listening to music on a cassette radio) and how to participate in a social activity (saying the rosary in a group) with a combination of learning methods. Transfer of these skills in similar contexts was difficult for MD. She never integrated the cassette radio into her daily life routine but she went regularly to the rosary activity, which was cued by an alarm clock. In sum, the learning methods used were very effective with these patients but transfer and spontaneous use were difficult. Since these aspects are essential to rehabilitation, they should be further explored in order to increase the effectiveness of cognitive interventions. [less ▲]

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See detailNew Level Determinations in Ne V
Bastin, Thierry ULg; Biémont, Emile ULg; Dumont, Paul-Dominique ULg et al

Poster (1996)

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See detailNew ligands for the living high-molecular-weight anionic (co)polymerization of acrylates in toluene at 0°C.1,2 3. Ligation of sec-butyllithium by lithium silanolates
Zundel, Thomas; Teyssié, Philippe; Jérôme, Robert ULg

in Macromolecules (1998), 31(17), 5577-5581

sec-Butyllithium combined with a new family of ligands, (i.e., lithium silanolates), has been used to initiate the ligated anionic polymerization of n-butyl acrylate (BuA) in toluene at low temperature ... [more ▼]

sec-Butyllithium combined with a new family of ligands, (i.e., lithium silanolates), has been used to initiate the ligated anionic polymerization of n-butyl acrylate (BuA) in toluene at low temperature. Compared to other μ-ligands, sBuMe2SiOLi is a more efficient stabilizer of the active centers. Thus, under selectively chosen reaction conditions, the polymerization proceeds quantitatively at −40 °C, producing a high-molecular-weight polymer with narrow-molecular-weight distribution (Mw/Mn < 1.2). When the copolymerization of BuA is initiated by a living {PMMALi, 5·sBuDLi} in toluene at −78 °C, the experimental data agree with a well-controlled block copolymerization reaction, since the final molecular-weight distribution is very narrow (Mw/Mn ≤ 1.1) and the polymerization efficiency very high. [less ▲]

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See detailNew ligands for the living isotactic anionic polymerization of methyl methacrylate in toluene at 0°C. 1. Ligation of butyllithium by lithium silanolates
Zundel, Thomas; Teyssié, Philippe; Jérôme, Robert ULg

in Macromolecules (1998), 31(8), 2433-2439

sBuLi and tBuLi have been combined with a new family of ligands, i.e. lithium silanolates, and used as initiators for the ligated anionic polymerization (LAP) of methyl methacrylate (MMA) in toluene at 0 ... [more ▼]

sBuLi and tBuLi have been combined with a new family of ligands, i.e. lithium silanolates, and used as initiators for the ligated anionic polymerization (LAP) of methyl methacrylate (MMA) in toluene at 0 °C. Compared to other known μ-ligands, the accordingly formed Bu(Me2)SiOLi are more efficient stabilizers for the active centers. Under appropriate reaction conditions, a fast polymerization proceeds quantitatively without self-termination at 0 °C and leads to high molecular weight polymer of narrow molecular weight distribution (Mw/Mn < 1.2) and high isotacticity (90% isotactic triads). [less ▲]

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See detailNew ligands for the living isotactic anionic polymerization of methyl methacrylate in toluene at 0°C. 2. 7Li NMR analysis of sec-butyllithium ligated by lithium silanolates
Zundel, Thomas; Zune, Catherine; Teyssié, Philippe et al

in Macromolecules (1998), 31(13), 4089-4092

The mixed associated species {xsBuLi, (y − x)sBuMe2SiOLi} formed by reaction of sec-Butyllithium (sBuLi) with octamethylcyclotetrasiloxane (Me2SiO)4 in toluene have been used to initiate the anionic ... [more ▼]

The mixed associated species {xsBuLi, (y − x)sBuMe2SiOLi} formed by reaction of sec-Butyllithium (sBuLi) with octamethylcyclotetrasiloxane (Me2SiO)4 in toluene have been used to initiate the anionic polymerization of methyl methacrylate (MMA) in that solvent at 0 °C. The active species generated by this new type of initiator have been characterized by 7Li NMR at 0 °C. The 7Li NMR spectra of sBuLi and sBuMe2SiOLi mixtures in toluene show that only one single type of {sBuLi, 5sBuMe2SiOLi} mixed species prevails at [sBuMe2SiOLi]/[sBuLi] molar ratios higher than ca. 21, as result of a large excess of {6sBuMe2SiOLi} species. The 7Li NMR has also concluded to the formation of {PMMALi, 5sBuMe2SiOLi} species upon the addition of MMA to that initiator solution, supporting the theory that only one type of ionic species is active during the MMA conversion. These active centers are stable for at least 1 h at 0 °C as confirmed by 7Li NMR. [less ▲]

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See detailNew light on the driving mechanism in roAp stars. I. Effects of metallicity
Théado, S.; Dupret, Marc-Antoine ULg; Noels-Grötsch, Arlette ULg et al

in Astronomy and Astrophysics (2009), 493

Context: Observations suggest that a relationship exists between the driving mechanism of roAp star pulsations and the heavy element distribution in these stars. Aims: We attempt to study the effects of ... [more ▼]

Context: Observations suggest that a relationship exists between the driving mechanism of roAp star pulsations and the heavy element distribution in these stars. Aims: We attempt to study the effects of local and global metallicity variations on the excitation mechanism of high order p-modes in A star models. Methods: We developed stellar evolutionary models to describe magnetic A stars with different global metallicity or local metal accumulation profiles. These models were computed with CLES (``Code Liègeois d'évolution stellaire''), and the stability of our models was assessed with the non-adiabatic oscillation code MAD. Results: Our models reproduce the blue edge of the roAp star instability strip, but generate a red edge hotter than the observed one, regardless of metallicity. Surprisingly, we find that an increase in opacity inside the driving region can produce a lower amount of driving, which we refer to as the ``inverse kappa-mechanism''. [less ▲]

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See detailNew light on the peculiar star HD108
Nazé, Yaël ULg; Barbieri, C.; Segafredo, A. et al

in Information Bulletin on Variable Stars (2006), 5693

HD 108 is a peculiar massive star of type Of?p, which present recurrent line profile variations. Archival data confirm the very long (50-60 yr) period of this star. Recent data show that the minimum state ... [more ▼]

HD 108 is a peculiar massive star of type Of?p, which present recurrent line profile variations. Archival data confirm the very long (50-60 yr) period of this star. Recent data show that the minimum state is not yet reached. [less ▲]

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See detailA new lineage of lichenized basidiomycetes inferred from a two-gene phylogeny: the Lepidostromataceae with three species from the Tropics
Ertz, Damien; Lawrey, J. D.; Sikaroodi, M. et al

in American Journal of Botany (2008), 95

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See detailNew linear lipopeptides produced by pseudomonas cichorii SF1-54 are involved in virulence, swarming motility, and biofilm formation
Pauwelyn, E.; Huang, C. J.; Ongena, Marc ULg et al

in Molecular Plant-Microbe Interactions [=MPMI] (2013), 26(5), 585-598

Pseudomonas cichorii is the causal agent of lettuce midrib rot, characterized by a dark-brown to green-black discoloration of the midrib. Formation of necrotic lesions by several plant-pathogenic ... [more ▼]

Pseudomonas cichorii is the causal agent of lettuce midrib rot, characterized by a dark-brown to green-black discoloration of the midrib. Formation of necrotic lesions by several plant-pathogenic pseudomonads is associated with production of phytotoxic lipopeptides, which contribute to virulence. Therefore, the ability of P. cichorii SF1-54 to produce lipopeptides was investigated. A cell-free culture filtrate of SF1-54 showed surfactant, antimicrobial, and phytotoxic activities which are typical for lipopeptides. High-performance liquid chromatography analysis of P. cichorii SF1-54 culture filtrate revealed the presence of seven compounds with lipopeptide characteristics. Two related lipopeptides, named cichofactin A and B, were studied in more detail: they are linear lipopeptides with a decanoic and dodecanoic lipid chain, respectively, connected to the N-terminus of an eight-amino-acid peptide moiety. Both cichofactins are new members of the syringafactin lipopeptide family. Furthermore, two nonribosomal peptide synthethase-encoding genes, cifA and cifB, were identified as responsible for cichofactin biosynthesis. A cifAB deletion mutant no longer produced cichofactins and was impaired in swarming motility but showed enhanced biofilm formation. Upon spray inoculation on lettuce, the cichofactindeficient mutant caused significantly less rotten midribs than the wild type, indicating that cichofactins are involved in pathogenicity of P. cichorii SF1-54. Further analysis revealed that P. cichorii isolates vary greatly in swarming motility and cichofactin production. © 2013 The American Phytopathological Society. [less ▲]

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See detailNew lipolitic enzymes identified by screening two metagenomic libraries derived from the soil of a winter wheat field
Stroobants, Aurore ULg; Martin, Renée ULg; Roosens, Lyse et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015), 19(2), 125-131

Lipolytic enzymes are widely distributed and fulfil important physiological functions in the microorganisms inhabiting diverse environments. Soils are rich, diversified environments containing microbial ... [more ▼]

Lipolytic enzymes are widely distributed and fulfil important physiological functions in the microorganisms inhabiting diverse environments. Soils are rich, diversified environments containing microbial communities that remain largely unknown. [less ▲]

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See detailNew lithostratigraphical, sedimentological, mineralogical and palaeontological data on the Mesozoic of Belgian Lorraine: a progress report
Boulvain, Frédéric ULg; Belanger, I.; Delsate, D. et al

in Geologica Belgica (2001), 3(1-2), 3-33

A multidisciplinary study of some extensively cored boreholes together with the new 1/25.000 geological mapping of wallonia lead us to propose a new lithostratigraphic canvas for belgian lorraine. This ... [more ▼]

A multidisciplinary study of some extensively cored boreholes together with the new 1/25.000 geological mapping of wallonia lead us to propose a new lithostratigraphic canvas for belgian lorraine. This area is located on the n-e border of the paris basin, south of the ardennes; the studied stratigraphic interval covers the keuper to the toarcian. Each of the newly defined units is sedimentologicaly interpreted on the basis of macroscopic and microscopic observations. Detailed palynological and claystratigraphical analyses have been performed, providingadditional stratigraphical, palaeoecological and sedimentological data. Moreover, a first sequence stratigraphic interpretation is proposed for this highly transgressive sedimentary body. The habay formation (conglomerates and red mudstones) is a fluvial unit, with immature channel conglomerates and paleosoils; the attert formation (dolomitic marls with gypsum and pseudomorphs) exhibites an evaporitic trend. The Mortinsart formation (sands and marls) corresponds to a restricted marine unit, evolving towards an alluvial plain (levallois member). The second cycle begins with the Jamoigne Formation (bioturbated marls and limestones), a marine subtidal restricted unit, evolving towards a more sandy sedimentary body (Metzert Member). The base of the third cycle corresponds to the rest of the Luxemburg Formation, comprising a succession of sandy waves. The Ethe Formation (laminar mudstones and marls) marks a deepening of the basin and the outset of open marine dysaerobic conditions. The Aubange Formation (bioturbated marls with sandstones and limestones) is characterized by the reappearance of a normal benthic fauna. The Grandcourt Formation (laminar mudstones and marls) marks a return to open marine dysaerobic conditions. The Mont-Saint-Martin Formation (marls, sandy marls and oolitic ironstone) is a highly regressive unit, while the Longwy Formation (limestones) marks the initiation of a carbonate platform. [less ▲]

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See detailA new long-tailed bsal bird from the Lower Cretaceous of north-eastern China
Lefevre, Ulysse ULg; Hu, Dongyu; Escuillié, François et al

in Biological Journal of the Linnean Society (2014), 113(3), 790-804

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See detailA new longirostrine ichthyosaur (Reptilia) from the Toarcian of France broadens the ecological diversity of the genus Temnodontosaurus
Martin, Jeremy; Fischer, Valentin ULg; Vincent, Peggy et al

Poster (2011, September)

The ichthyosaur genus Temnodontosaurus has always been viewed as a top predator of the Early Jurassic marine environments, while other contemporaneous ichthyosaurs such as leptonectids and stenopterygiids ... [more ▼]

The ichthyosaur genus Temnodontosaurus has always been viewed as a top predator of the Early Jurassic marine environments, while other contemporaneous ichthyosaurs such as leptonectids and stenopterygiids were occupying the lower trophic levels. We describe here an almost complete skeleton of this successful genus from the middle Toarcian (Lower Jurassic) of the Beaujolais foothills near Lyon, France, and assign it to a new species of Temnodontosaurus. This specimen exhibits cranial peculiarities such as a thin, elongated, and likely edentulous rostrum, as well as a reduced quadrate. Such morphological combination indicates dietary preferences that markedly differ from other species referred to as Temnodontosaurus. Despite a conservative postcranial skeleton, we propose that Temnodontosaurus is one of the most ecologically diverse genera of ichthyosaurs, including apex predators, small and soft prey longirostrine hunters, and generalized forms. Ammonites collected along the described specimen indicate that the new species is younger (bifrons ammonite zone) than most known Toarcian ichthyosaurs and therefore slightly postdates the severe environmental changes and marine invertebrate extinctions that occur during the Toarcian Oceanic Anoxic Event. The present study hence raises the question whether the speciation of Temnodontosaurus towards a new ecological niche, may have been a consequence of the post-crisis marine ecosystem reorganization. [less ▲]

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