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See detailA dynamic simulation approach to identify additional reactive reserves against long-term voltage instability
Papangelis, Lampros ULg; Panciatici, Patrick; Debry, Marie-Sophie et al

in Proc. of IEEE PES 2015 PowerTech conference (in press)

A simple method is proposed to identify additional reactive reserves enabling to counteract long-term voltage instability after a large disturbance. In contrast to the many references based on power flow ... [more ▼]

A simple method is proposed to identify additional reactive reserves enabling to counteract long-term voltage instability after a large disturbance. In contrast to the many references based on power flow calculations, the method resorts to dynamic simulation. The post-disturbance system evolution is simulated in the presence of time-varying shunt susceptances with specified rate of change. This allows to deal with dynamic issues such as the required speed of the additional reactive power sources, or the onset of unstable electromechanical oscillations. Furthermore, a compromise is sought between the speed of action and the volume of additional compensation. The method is demonstrated on a detailed model of the Nordic test system. [less ▲]

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See detailArsinoe II come dea attraverso le sue epiclesi cultuali
Caneva, Stefano ULg

in Athenaeum : Studii Periodici di Letteratura e Storia (in press), 103(1), 95-122

Dopo una introduzione storica e storiografica sul significato dei culti regali ellenistici, l’intervento esamina alcuni dei nomi divini attribuiti ad Arsinoe II nelle fonti letterarie e documentarie, con ... [more ▼]

Dopo una introduzione storica e storiografica sul significato dei culti regali ellenistici, l’intervento esamina alcuni dei nomi divini attribuiti ad Arsinoe II nelle fonti letterarie e documentarie, con l’eccezione dell’epiclesi esclusiva Philadelphos. Scopo della ricerca è 1) una valutazione delle strategie di inserimento della nuova dea nel pantheon tradizionale; 2) una riflessione sull’autoconsapevolezza degli antichi in relazione alla propria tradizione religiosa, per come essa si manifesta attraverso l’oculata manipolazione di un elemento essenziale nella definizione della divinità, qual è il nome divino. Un’Appendice elenca, in tre tabelle, tutte le denominazioni greche di Arsinoe II (esclusa Philadelphos), fornendo indicazioni sulla fonte, la sua collocazione spaziale e temporale e sulla divinità tradizionale di riferimento. [less ▲]

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See detailMagnetic fields in O-, B- and A-type stars on the main sequence
Briquet, Maryline ULg

in CoRoT Symposium 3 / Kepler KASC-7 joint meeting (in press)

In this review, the latest observational results on magnetic fields in main-sequence stars with radiative envelopes are summarised together with the theoretical works aimed at explaining them.

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See detailCompte rendu de G. TOUSSAINT, Kreuz und Knochen. Reliquien zur Zeit der Kreuzzüge, Berlin, 2011.
George, Philippe ULg

in Cahiers de Civilisation Médiévale (in press)

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See detailA new formulation of state estimation in distribution systems including demand and generation states
Rousseaux, Patricia ULg; Toubeau, Jean-François; De Grève, Zacharie et al

in proceeedings of the 2015 Power Tech conference (in press)

Distribution system state estimation faces a major difficulty: the lack of real-time measurements. This imposes to add information, usually pseudo-measurements from historical data. This paper proposes a ... [more ▼]

Distribution system state estimation faces a major difficulty: the lack of real-time measurements. This imposes to add information, usually pseudo-measurements from historical data. This paper proposes a different, novel formulation of state estimation relying on the classification of loads into components (e.g. residential, commercial, etc.) and accounting for dispersed generation. The approach “by-passes” the use of pseudo-measurements by expressing the medium-voltage bus injections as functions of a small number of active power components at low-voltage level, treated as additional state variables. The injections at medium-voltage buses become equality constraints. A procedure to identify the above functions is detailed, which takes advantage of data collected by smart meters. [less ▲]

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See detailDieux des Grecs - Dieux des Romains. Panthéons en dialogue à travers l'histoire et l'historiographie
Bonnet, Corinne; Pirenne-Delforge, Vinciane ULg; Pironti, Gabriella

Book published by Institut historique belge de Rome (in press)

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See detailUn type picard par-delà les frontières : le <nom jeté>
Baiwir, Esther ULg

in Dialectes de Wallonie (in press), 36

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See detailThe soundtrack of RR Lyrae in Omega Cen at high-frequency
Calamida, A.S.; Randall, S.K.; Monelli, M. et al

in Memorie della Società Astronomica Italiana : Journal of the Italian Astronomical Society (in press)

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See detailCompte rendu de D. van Mal-Maeder, A. Burnier, L. Núñez (éds.): Jeux de voix. Énonciation, intertextualité et intentionnalité dans la littérature antique
Macedo, Gabriel ULg

in Antiquité Classique : Revue Interuniversitaire d'Etudes Classiques (in press)

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See detailLes animateurs de la vie littéraire en Belgique francophone : de leur rôle interne à leur position de médiateur transnational
Dozo, Björn-Olav ULg

in Blanchard, Nelly; Thomas, Mannaig (Eds.) Des littératures périphériques (in press)

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See detailImpacts of climate change on future flood damage on the river Meuse, with a distributed uncertainty analysis
Detrembleur, Sylvain; Stilmant, Frédéric ULg; Dewals, Benjamin ULg et al

in Natural Hazards (in press)

Flood-risk assessments are an objective and quantitative basis for implementing harmonized flood mitigation policies at the basin scale. However, the generated results are subject to different sources of ... [more ▼]

Flood-risk assessments are an objective and quantitative basis for implementing harmonized flood mitigation policies at the basin scale. However, the generated results are subject to different sources of uncertainty arising from underlying assumptions, data availability and the random nature of the phenomenon. These sources of uncertainty are likely to bias conclusions because they are irregularly distributed in space. Therefore, this paper addresses the question of the influence of local features on the expected annual damage in different municipalities. Based on results generated in the frame of a transnational flood-risk-assessment project for the river Meuse (Western Europe) taking climate change into account, the paper presents an analysis of the relative contributions of different sources of uncertainty within one single administrative region (the Walloon region in Belgium, i.e. a river reach of approximately 150 km). The main sources of uncertainty are not only found to vary both from one municipality to the other and in time, but also to induce opposite effects on the computed damage. Nevertheless, practical conclusions for policy-makers can still be drawn. [less ▲]

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See detailMathématiques convoquées par le registre graphique au sein du cours de physique
Renkens, Céline; Henry, Valérie ULg

in Actes de la CIEAEM 66 (in press)

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See detailA radio-map of the colliding winds in the very massive binary system HD93129A
Benaglia, Paula; Marcote, Benito; Moldon, Javier et al

in Astronomy and Astrophysics (in press)

Radio observations are an effective tool to discover particle acceleration regions in colliding-wind binaries, through detection of synchrotron radiation; these regions are natural laboratories for the ... [more ▼]

Radio observations are an effective tool to discover particle acceleration regions in colliding-wind binaries, through detection of synchrotron radiation; these regions are natural laboratories for the study of relativistic particles.Wind-collision region (WCR) models can reproduce the radio continuum spectra of massive binaries that contain both thermal and non-thermal radio emission; however, key constraints for models come from high-resolution imaging. Only five WCRs have been resolved to date at radio frequencies at milliarcsec (mas) angular scales. The source HD93129A, prototype of the very few known O2 I stars, is a romising target for study: recently, a second massive, early-type star about 50 mas away was discovered, and a non-thermal radio source detected in the region. Preliminary long-baseline array data suggest that a significant fraction of the radio emission from the system comes from a putative WCR. We sought evidence that HD93129A is a massive binary system with colliding stellar winds that produce non-thermal radiation, through spatially resolved images of the radio emitting regions. Methods.We completed observations with the Australian Long Baseline Array (LBA) to resolve the system at mas angular resolutions and reduced archival Australia Telescope Compact Array (ATCA) data to derive the total radio emission. We also compiled optical astrometric data of the system in a homogeneous way. We reduced historical Hubble Space Telescope data and obtained absolute and relative astrometry with milliarcsec accuracy. The astrometric analysis leads us to conclude that the two stars in HD93129A form a gravitationally bound system. The LBA data reveal an extended arc-shaped non-thermal source between the two stars, indicative of a WCR. The wind momentum-rate ratio of the two stellar winds is estimated. The ATCA data show a point source with a change in flux level between 2003-4 and 2008-9, that is modeled with a non-thermal power-law spectrum with spectral indices of - 1:03 +/- 0:09 and -1:21 +/- 0:03 respectively. The mass-loss rates derived from the deduced thermal radio emission and from the characteristics of the WCR are consistent with estimates derived by other authors. [less ▲]

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See detailShort communication: Evaluation of the microbiota of kefir samples using metagenetic analysis targeting the 16S and 26S ribosomal DNA fragments
Korsak Koulagenko, Nicolas ULg; Taminiau, Bernard ULg; Leclercq, Mathilde et al

in Journal of Dairy Science (in press)

Milk kefir is produced by fermenting milk in the presence of kefir grains. This beverage has several benefits for human health. The aim of this experiment was to analyze 5 kefir grains (and their products ... [more ▼]

Milk kefir is produced by fermenting milk in the presence of kefir grains. This beverage has several benefits for human health. The aim of this experiment was to analyze 5 kefir grains (and their products) using a targeted metagenetic approach. Of the 5 kefir grains analyzed, 1 was purchased in a supermarket, 2 were provided by the Ministry of Agriculture (Namur, Belgium), and 2 were provided by individuals. The metagenetic approach targeted the V1-V3 fragment of the 16S ribosomal (r)DNA for the grains and the resulting beverages at 2 levels of grain incorporation (5 and 10%) to identify the bacterial species population. In contrast, the 26S rDNA pyrosequencing was performed only on kefir grains with the aim of assessing the yeast populations. In parallel, pH measurements were performed on the kefir obtained from the kefir grains using 2 incorporation rates. Regarding the bacterial population, 16S pyrosequencing revealed the presence of 20 main bacterial species, with a dominance of the following: Lactobacillus kefiranofaciens, Lactococcus lactis ssp. cremoris, Gluconobacter frateurii, Lactobacillus kefiri, Acetobacter orientalis, and Acetobacter lovaniensis. An important difference was noticed between the kefir samples: kefir grain purchased from a supermarket (sample E) harbored a much higher proportion of several operational taxonomic units of Lactococcus lactis and Leuconostoc mesenteroides. This sample of grain was macroscopically different from the others in terms of size, apparent cohesion of the grains, structure, and texture, probably associated with a lower level of Lactobacillus kefiranofaciens. The kefir (at an incorporation rate of 5%) produced from this sample of grain was characterized by a lower pH value (4.5) than the others. The other 4 samples of kefir (5%) had pH values above 5. Comparing the kefir grain and the kefir, an increase in the population of Gluconobacter in grain sample B was observed. This was also the case for Acetobacter orientalis in sample D. In relation to 26S pyrosequencing, our study revealed the presence of 3 main yeast species: Naumovozymaspp., Kluyveromyces marxianus, and Kazachastania khefir. For Naumovozyma, further studies are needed to assess the isolation of new species. In conclusion, this study has proved that it is possible to establish the patterns of bacterial and yeast composition of kefir and kefir grain. This was only achieved with the use of high-throughput sequencing techniques. [less ▲]

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See detailStéphane Mallarmé (1842-1898)
Durand, Pascal ULg

in Sapiro, Gisèle (Ed.) Dictionnaire international Bourdieu (in press)

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See detailWhere do hybrids come from? Entrepreneurial team heterogeneity as an avenue for the emergence of hybrid organizations
Dufays, Frédéric ULg; Huybrechts, Benjamin ULg

in International Small Business Journal (in press)

This conceptual paper aims to respond to the poorly addressed question of the emergence of hybrid organizations – i.e. organizations that embrace several institutional logics. It does so by developing a ... [more ▼]

This conceptual paper aims to respond to the poorly addressed question of the emergence of hybrid organizations – i.e. organizations that embrace several institutional logics. It does so by developing a model and a set of propositions focusing on the heterogeneity of the entrepreneurial team as a possible driver for hybridity throughout the entrepreneurial process and up to the emergence of a hybrid organization. As contributions to the literatures on (collective) entrepreneurship, imprinting and hybrid organizations, we advance several avenues and conditions under which the heterogeneity of the entrepreneurial team may imprint the entrepreneurial process and lead to the creation of hybrid organizations. Our propositions connect the individual, team and organizational levels and thus advance our understanding of how institutional logics can be combined across different levels of analysis and throughout the stages of an entrepreneurial process. [less ▲]

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See detailOption Replication and the Performance of a Market Timer
Hübner, Georges ULg

in Studies in Economics & Finance (in press)

The Treynor and Mazuy framework is a widely used return-based model of market timing. However, existing corrections to the regression intercept can be manipulated through derivatives trading. We propose ... [more ▼]

The Treynor and Mazuy framework is a widely used return-based model of market timing. However, existing corrections to the regression intercept can be manipulated through derivatives trading. We propose an adjustment based on Merton's option replication approach. The linear and quadratic coefficients of the regression are exploited to assess the cost of the replicating option that yields similar convexity for a passive portfolio. A similar reasoning applies for various timing patterns and in multi-factor models. The proposed framework induces a potential rebalancing risk and involves the delicate issue of choosing the cheapest option. We show that these issues can be overcome for reasonable tolerance levels. [less ▲]

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See detailImmune Recovery after Allogeneic Hematopoietic Stem Cell Transplantation following Flu-TBI versus TLI-ATG Conditioning
HANNON, Muriel ULg; BEGUIN, Yves ULg; Ehx, Grégory ULg et al

in Clinical Cancer Research : An Official Journal of the American Association for Cancer Research (in press)

Purpose: A conditioning regimen for allogeneic hematopoietic cell transplantation (HCT) combining total lymphoid irradiation (TLI) plus anti-thymocyte globulin (ATG) has been develop to induce graft ... [more ▼]

Purpose: A conditioning regimen for allogeneic hematopoietic cell transplantation (HCT) combining total lymphoid irradiation (TLI) plus anti-thymocyte globulin (ATG) has been develop to induce graft-versus-tumor effects without graft-versus-host disease (GVHD). Experimental Design: We compared immune recovery in 53 patients included in a phase II randomized study comparing nonmyeloablative HCT following either fludarabine plus 2 Gy total body irradiation (TBI arm, n=28) or 8 Gy TLI plus anti-thymocyte globulin (TLI arm, n=25). Results: In comparison to TBI patients, TLI patients had a similarly low 6-month incidence of grade II-IV acute GVHD, a lower incidence of moderate/severe chronic GVHD (P=0.02), a higher incidence of CMV reactivation (P<0.001), and a higher incidence of relapse (P=0.01). While recovery of total CD8+ T cells was similar in the two groups, with median CD8+ T cell counts reaching the normal values 40-60 days after allo-HCT, TLI patients had lower percentages of naïve CD8 T cells. Median CD4+ T cell counts did not reach the lower limit of normal values the first year after allo-HCT in the two groups. Further, CD4+ T cell counts were significantly lower in TLI than in TBI patients the first 6 months after transplantation. Interestingly, while median absolute regulatory T cell (Treg) counts were comparable in TBI and TLI patients, Treg/naïve CD4+ T cell ratios were significantly higher in TLI than in TBI patients the 2 first years after transplantation. Conclusions: Immune recovery differs substantially between these two conditioning regimens possibly explaining the different clinical outcomes observed (NCT00603954). [less ▲]

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See detailGlobally, functional traits are weak predictors of juvenile tree growth, and we do not know why
Paine, C.E. Thimothy; Amissah, Lucy; Auge, Harald et al

in Journal of Ecology (in press)

1. Plant functional traits, in particular specific leaf area (SLA), wood density and seed mass, are often good predictors of individual tree growth rates within communities. Individuals and species with ... [more ▼]

1. Plant functional traits, in particular specific leaf area (SLA), wood density and seed mass, are often good predictors of individual tree growth rates within communities. Individuals and species with high SLA, low wood density and small seeds tend to have faster growth rates. 2. If community-level relationships between traits and growth have general predictive value, then similar relationships should also be observed in analyses that integrate across taxa, biogeographic regions and environments. Such global consistency would imply that traits could serve as valuable proxies for the complex suite of factors that determine growth rate, and, therefore, could underpin a new generation of robust dynamic vegetation models. Alternatively, growth rates may depend more strongly on the local environment or growth–trait relationships may vary along environmental gradients. 3. We tested these alternative hypotheses using data on 27 352 juvenile trees, representing 278 species from 27 sites on all forested continents, and extensive functional trait data, 38% of which were obtained at the same sites at which growth was assessed. Data on potential evapotranspiration (PET), which summarizes the joint ecological effects of temperature and precipitation, were obtained from a global data base. 4. We estimated size-standardized relative height growth rates (SGR) for all species, then related them to functional traits and PET using mixed-effect models for the fastest growing species and for all species together. 5. Both the mean and 95th percentile SGR were more strongly associated with functional traits than with PET. PET was unrelated to SGR at the global scale. SGR increased with increasing SLA and decreased with increasing wood density and seed mass, but these traits explained only 3.1% of the variation in SGR. SGR–trait relationships were consistently weak across families and biogeographic zones, and over a range of tree statures. Thus, the most widely studied functional traits in plant ecology were poor predictors of tree growth over large scales. 6. Synthesis. We conclude that these functional traits alone may be unsuitable for predicting growth of trees over broad scales. Determining the functional traits that predict vital rates under specific environmental conditions may generate more insight than a monolithic global relationship can offer. [less ▲]