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See detailIntraspecific variation of copper tolerance of four endemic plant species from the katangan Copperbelt (D. R. Congo)
Boisson, Sylvain ULg; garin, olivier; Seleck, Maxime ULg et al

Conference (2014, August 04)

Harsh ecosystems are at the origin of speciation processes in plant communities. In metalliferous areas, plants develop physiological adaptations to tolerate metal excesses which lead to high species and ... [more ▼]

Harsh ecosystems are at the origin of speciation processes in plant communities. In metalliferous areas, plants develop physiological adaptations to tolerate metal excesses which lead to high species and population diversity. South of the Katanga province (D.R. Congo), plant communities occur on soils with one of the world’s largest concentrations of copper and cobalt. More than 600 species including 54 endemics are distributed along a copper gradient (up to 10 000 mg kg-1 available Cu) and the populations are isolated on more than 100 copper hills scattered in miombo forest. In order to improve restoration strategies of threatened species, we aimed to identify intraspecific copper tolerance of 4 endemic plant species from katangan copper outcrops: Crotalaria cobalticola, Diplolophium marthozianum, Gladiolus ledoctei and Triumfetta welwitschii. Seeds were collected in 3 different populations in the katangan Copperbelt and sown according three soil contamination modalities: control (no addition of Cu), 100 mg kg-1 and 1000 mg kg-1 of Cu concentration using hydrated copper (II) sulfate. For each combination (species x populations x soils), we had 10 repetitions. For each population, sample of 5 seeds was weighed before seedling in pot in November 2013. One individual by pot was kept for measures. Height (cm), number of leaves, number of flowers and number of fruits were measured once a week during one rainy season. For all species, no significant difference of copper tolerance appeared between populations. In contrast, populations had distinct germination rate and growth rate, especially for T. welwitshii and D. marthozianum. C. cobalticola grew significantly better in highly contaminated soil than other soils. G. ledoctei did not show any significant difference between populations and soil treatments. [less ▲]

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See detailcompte rendu de : Geiger, Joseph. Hellenism in the East: studies on Greek intellectuals in Palestine.
Rochette, Bruno ULg

in Bryn Mawr Classical Review [=BMCR] (2014)

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See detailEn attendant Toussaint
Demoulin, Laurent ULg

E-print/Working paper (2014)

Présentation et analyse de deux courtes pièces, Rideau et Ni l'un ni l'autre, écrites par Jean-Philippe Toussaint en 1981, quand il était un jeune auteur inconnu influencé par Samuel Beckett.

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See detailX-rays from magnetic massive OB stars
Petit, V.; Cohen, D. H.; Nazé, Yaël ULg et al

in IAU Symposium (2014, August 01)

The magnetic activity of solar-type and low-mass stars is a well known source of coronal X-ray emission. At the other end of the main sequence, X-rays emission is instead associated with the powerful ... [more ▼]

The magnetic activity of solar-type and low-mass stars is a well known source of coronal X-ray emission. At the other end of the main sequence, X-rays emission is instead associated with the powerful, radiatively driven winds of massive stars. Indeed, the intrinsically unstable line-driving mechanism of OB star winds gives rise to shock-heated, soft emission (~0.5 keV) distributed throughout the wind. Recently, the latest generation of spectropolarimetric instrumentation has uncovered a population of massive OB-stars hosting strong, organized magnetic fields. The magnetic characteristics of these stars are similar to the apparently fossil magnetic fields of the chemically peculiar ApBp stars. Magnetic channeling of these OB stars' strong winds leads to the formation of large-scale shock-heated magnetospheres, which can modify UV resonance lines, create complex distributions of cooled Halpha emitting material, and radiate hard (~2-5 keV) X-rays. This presentation summarizes our coordinated observational and modelling efforts to characterize the manifestation of these magnetospheres in the X-ray domain, providing an important contrast between the emission originating in shocks associated with the large-scale fossil fields of massive stars, and the X-rays associated with the activity of complex, dynamo-generated fields in lower-mass stars. [less ▲]

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See detailA Deep Chandra Observation of the Giant H II Region N11. I. X-Ray Sources in the Field
Nazé, Yaël ULg; Wang, Q. Daniel; Chu, You-Hua et al

in Astrophysical Journal Supplement Series (2014), 213

A very sensitive X-ray investigation of the giant H II region N11 in the Large Megallanic Cloud was performed using the Chandra X-ray Observatory. The 300 ks observation reveals X-ray sources with ... [more ▼]

A very sensitive X-ray investigation of the giant H II region N11 in the Large Megallanic Cloud was performed using the Chandra X-ray Observatory. The 300 ks observation reveals X-ray sources with luminosities down to 10[SUP]32[/SUP] erg s[SUP]–1[/SUP], increasing the number of known point sources in the field by more than a factor of five. Among these detections are 13 massive stars (3 compact groups of massive stars, 9 O stars, and one early B star) with log (L [SUB]X[/SUB]/L [SUB]BOL[/SUB]) ~–6.5 to –7, which may suggest that they are highly magnetic or colliding-wind systems. On the other hand, the stacked signal for regions corresponding to undetected O stars yields log (L [SUB]X[/SUB]/L [SUB]BOL[/SUB]) ~–7.3, i.e., an emission level comparable to similar Galactic stars despite the lower metallicity. Other point sources coincide with 11 foreground stars, 6 late-B/A stars in N11, and many background objects. This observation also uncovers the extent and detailed spatial properties of the soft, diffuse emission regions, but the presence of some hotter plasma in their spectra suggests contamination by the unresolved stellar population. [less ▲]

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See detailStandardization of DiaSorin and Roche automated third generation PTH assays with an international standard: impact on clinical populations
CAVALIER, Etienne ULg; DELANAYE, Pierre ULg; LUKAS, Pierre ULg et al

in Clinical Chemistry & Laboratory Medicine (2014), 52(8), 1137-41

Background: Standardization of parathyroid hormone (PTH) assays is a major issue, especially in hemodialyzed (HD) patients. Two automated third generation PTH assays (Roche Elecsys and DiaSorin Liaison ... [more ▼]

Background: Standardization of parathyroid hormone (PTH) assays is a major issue, especially in hemodialyzed (HD) patients. Two automated third generation PTH assays (Roche Elecsys and DiaSorin Liaison) are now available. These assays are specific for the (1-84) PTH and do not cross-react with the (7-84) fragment, contrary to second generation (intact) assays. We aimed to calibrate the two methods against the WHO International PTH Standard (IS) 95/646 to see if the two assays could provide comparable results in a population of healthy subjects, HD patients and patients suffering from primary hyperparathyroidism (PHP). Methods: We selected 79 healthy subjects and two populations of patients presenting PTH disorders: 56 HD and 27 PHP patients. We reconstituted the IS in a pool of human serum containing undetectable levels of 1-84 PTH and prepared 13 serum standards ranging from 0 to 2000 pg/mL. The standards were run on the two instruments to calibrate the assays on the IS. The different populations were run before and after restandardization. Results: As these kits were differently calibrated, the results obtained after restandarization were significantly different. Restandardization process improved concordance between assays and, taking the analytical variability of the two kits into account, the results could be considered to be similar. Conclusions: Restandardization of automated third generation PTH assays with the WHO 1-84 PTH Standard significantly reduces inter-method variability. Reference ranges and raw values are totally transposable from one method to the other in healthy subjects, but also in diseased patients, e.g., with HD or those suffering from PHP. [less ▲]

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See detailRegional, Interregional and Global Arrangements and Multilateral Organizations
Santander, Sébastian ULg

in Telò, Mario (Ed.) European Union and New Regionalism. Regional actors and global governance in a post-hegemonic era (2014)

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See detailImprovement of defect detection in shearography by using Principal Component Analysis
Vandenrijt, Jean-François ULg; Lièvre, Nicolas; Georges, Marc ULg

in Proceedings of Conference on Interferometry XVII: Techniques and Analysis (2014, August)

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See detailDeveloping situational judgment tests to assess organizational citizenship behaviours
Lothe, Benoit ULg; Hansez, Isabelle ULg

Conference (2014, August)

a) Purpose As Organizational Citizenship Behaviours (OCBs) positively influence a number of important outcomes (e.g. job performance, unit productivity, organizational efficiency, etc.) and are valued by ... [more ▼]

a) Purpose As Organizational Citizenship Behaviours (OCBs) positively influence a number of important outcomes (e.g. job performance, unit productivity, organizational efficiency, etc.) and are valued by managers as well, Organ, Podsakoff and Podsakoff (2010) assert the need “to try to identify and select those job candidates who have a propensity to exhibit these behaviours” (p.314). This study provides some empirical evidence about using Situational Judgment Tests (SJTs) for this specific target and allows us to discuss the main methodological issues in the development of such SJTs. b) Method Based on relevant best practices and recommendations from the literature (e.g. Weekley, Ployhart & Holtz, 2006), two distinct SJTs were especially developed to comply with OCBs assessment. The two SJTs differ on their job specificity degree (project manager in the industrial sector vs transversal function in the services sector), both propose ten different work related situations and, for each stem, five action proposals are available. Data were collected through online survey on two different samples (220 white collars professionals and 291 university students). Professionals were allowed to choose which SJT they wanted to participate, students were randomized within the two SJTS. An experimental manipulation of the response instructions (ipsative vs normative) was added within the student sample. OCBs were concurrently collected using self-reported measurement scales. c) Results In both samples (respectively professionals and students), the internal consistency was higher for the “job specific” SJT (α = .79 & .81) than for the “transversal job” SJT (α = .49 & 64). Notwithstanding, significant relations were found between the SJT scores and overall OCB ratings for both of the SJT forms in each of the two samples (r ranged from .30 to .57). Other specifics findings also provided substantial evidence for the concurrent validity of the SJTs to measure sub-dimensions of OCBs (altruism, courtesy, civic virtue, sportsmanship, loyalty and voice). d) Conclusions This study is, to our knowledge, the first to address the development and validation of a SJT for the assessment of OCBs. Review of the literature indicates that researches on techniques to predict OCBs are scarce and the present findings appear to surpass the average personality traits validity coefficients (r= .20) according to Organ & al. (2010)’s meta-analysis. There are two main practical implications. The first is the opportunity to use OCBs-SJTs as an alternative to assess applicants OCBs for job-specific or generic personnel selection issue. The second is to provide methodological development advices (e.g. the choice of response instruction) to ensure the SJT match the OCBs assessment requirement. Principal current limitations call for further research development that will be discussed: using different sources of OCBs rating, testing the incremental validity on personality tests, determining whether OCBs-SJTs are correlated with cognitive ability and establishing criterion validity with job performance. [less ▲]

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See detailNatural intrauterine infection with Schmallenberg virus in malformed newborn calves: pathology and distribution of viral RNA
Bayrou, Calixte ULg; Garigliany, Mutien-Marie ULg; Sarlet, Michaël ULg et al

in Emerging Infectious Diseases (2014), 20(8),

We comprehensively surveyed morphologic alterations in calves naturally infected in utero by Schmallenberg virus (SBV) and born deformed. SBV-specific RNA was distributed unevenly in different tissues ... [more ▼]

We comprehensively surveyed morphologic alterations in calves naturally infected in utero by Schmallenberg virus (SBV) and born deformed. SBV-specific RNA was distributed unevenly in different tissues. Implications for diagnosic procedures are highlighted. [less ▲]

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See detailPhénologie et intensité de la migration postnuptiale diurne en Ardenne du nord-est par le suivi migratoire (Ramecroix, 2006 à 2010)
Beckers, Arnaud ULg; Baron, André

in Aves (2014), 51(2), 87-106

Nous présentons les résultats de 5 années de suivi migratoire postnuptial en Ardenne du nord-est (site de Ramecroix) de 2006 à 2010. La phénologie et l’intensité du flux migratoire ont été calculées pour ... [more ▼]

Nous présentons les résultats de 5 années de suivi migratoire postnuptial en Ardenne du nord-est (site de Ramecroix) de 2006 à 2010. La phénologie et l’intensité du flux migratoire ont été calculées pour les 19 espèces les plus fréquentes. De manière générale, la phénologie montre une forte variabilité interannuelle par espèce. Le caractère extrêmement concentré dans le temps du passage a été mis en évidence chez deux espèces (Vanneau huppé et Grive musicienne). La phénologie est ensuite comparée à celle des Pays-Bas et celle des Awirs (Liège) et suggère des variations géographiques. L’ensemble du jeu de données constitue une référence utile pour de futures études traitant de la variabilité spatiale des flux migratoires. [less ▲]

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See detailOlympiades mathématiques belges - Recueil de questions - Tome 8 (2011-2014)
Dupont, Pascal ULg; Sebille, Michel

Book published by SBPMef (2014)

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See detailThe quest for rurality in Wallonia in 2013 (Belgium)
Schmitz, Serge ULg

in Bokwa, Anita (Ed.) Changes, Challenges Responsability. IGU 2014 Book of Abstarcts. (2014, August)

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See detailDiplomacia pública, ¿de la teoría a la práctica?: El caso de la Unión Europea en Brasil
Azpíroz Manero, María Luisa ULg

Conference (2014, August)

El entusiasmo académico por la diplomacia pública no se refleja en una atención específica a la misma en las estrategias de política exterior de la Unión Europea (UE). Sin embargo, su presencia se revela ... [more ▼]

El entusiasmo académico por la diplomacia pública no se refleja en una atención específica a la misma en las estrategias de política exterior de la Unión Europea (UE). Sin embargo, su presencia se revela en múltiples iniciativas en las que los agentes no gubernamentales tienen un papel clave como receptores o actores: actividades de cooperación, de intercambio, informativas. La diplomacia pública es una actividad diplomática y de comunicación política internacional que busca influenciar a públicos extranjeros con el fin de contribuir al logro de objetivos de política exterior y/o generar una imagen positiva. Funciona como una herramienta efectiva para movilizar recursos de poder blando, un poder basado en la atracción y la persuasión que se produce de modo indirecto cuando los actores políticos movilizan recursos como la cultura, los valores, las instituciones y las estrategias de política exterior. Pese a la crisis económica, la UE conserva un gran potencial de poder blando. Por eso, y dada la relevancia de Brasil como socio prioritario en la región latinoamericana, este artículo investiga qué diplomacia pública ha desarrollado la UE en este país los últimos tres años, así como su correspondencia con el cuerpo teórico sobre esta actividad. [less ▲]

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See detailThe cerato-mandibular ligament: a key functional trait for grazing in damselfishes (Pomacentridae)
Olivier, Damien ULg; Frederich, Bruno ULg; Spanopoulos-Zarco, Milton et al

in Frontiers in Zoology (2014), 11(63), 1-14

Introduction: The success of a taxonomic group can be promoted by a key character that allows the group to interact with its environment in a different way and to potentially occupy new niches. The ... [more ▼]

Introduction: The success of a taxonomic group can be promoted by a key character that allows the group to interact with its environment in a different way and to potentially occupy new niches. The Pomacentridae possess a synapomorphic trait, the cerato-mandibular (c-md) ligament, which joins the hyoid bar to the inner part of the lower jaw. It has previously been shown that this ligament is a key trait in communication in damselfishes because it enables them to slam the oral jaws shut causing teeth collision and sound production. This specific behavior of mouth closing could, however, also be used for other tasks, such as feeding. Many territorial damselfishes are referred to as farmers, due to their ability to manage algal crops on which they feed. This study hypothesizes that the c-md ligament provides an advantage for grazing filamentous algae, and should thus be considered a key trait for farming behavior. Results: The kinematic patterns associated with sound production and biting filamentous algae or attached animal prey are all based on the same mechanism and are associated with a slam of the oral jaws. We observed that transection of the c-md ligaments makes the fish unable to perform such actions. We also counted biting rates on filamentous algae in fish with and without the c-md ligament and observed a drop of more than 80% in the latter. Conclusion: This study shows that the c-md ligament is a key trait both for sound production and for grazing activities in damselfishes. The buccal jaw slam enables the fish to perform accurate strikes on small filamentous algae. This kind of bite probably plays a major role in farming activity and allows grazing damselfishes to occupy distinct niches, possibly increasing their competitive evolutionary success. [less ▲]

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See detailAn AC OPF-based Heuristic Algorithm for Optimal Transmission Switching
Capitanescu, Florin; Wehenkel, Louis ULg

in Proceedings of the 18th Power Systems Computation Conference (2014, August)

This paper focuses on reducing generators dispatch cost by means of transmission line switching. The problem is formulated as a mixed-integer nonlinear program (MINLP) optimal power flow (OPF). A scalable ... [more ▼]

This paper focuses on reducing generators dispatch cost by means of transmission line switching. The problem is formulated as a mixed-integer nonlinear program (MINLP) optimal power flow (OPF). A scalable heuristic algorithm is proposed to break-down the complexity of the problem due to the huge combinatorial space. The algorithm aims at providing the sequence of lines to be removed from service, one at the time, until no further decrease in the dispatch cost can be obtained. It identifies the line candidate for removal at each step by exploiting the (continuously relaxed values of) lines breaker statuses at the solution of a relaxed OPF problem. The algorithm thus relies on solving a sequence of OPF problems formulated as nonlinear programs (NLPs). The effectiveness of the approach is demonstrated on the IEEE118-bus system. Results show that the approach can provide good quality sub-optimal solutions with relatively small computational effort and by removing only few lines from service. [less ▲]

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