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See detailHow do paedomorphic newts cope with lake drying?
Denoël, Mathieu ULg

in Ecography (2003), 26(4), 405-410

Paedomorphosis, in which adult individuals retain larval traits, is widespread in newts and salamanders. Most evolutionary models predict the maintenance of this life-history trait in favourable aquatic ... [more ▼]

Paedomorphosis, in which adult individuals retain larval traits, is widespread in newts and salamanders. Most evolutionary models predict the maintenance of this life-history trait in favourable aquatic habitats surrounded by hostile terrestrial environments. Nevertheless, numerous ponds inhabited by paedomorphic individuals are unpredictable and temporary. In an experimental framework, I showed that paedomorphic newts were able to metamorphose and thus survive in the absence of water. However, the mere decrease of water level or the life space do not seem to induce metamorphosis in paedomorphs. On the contrary, drying up induces almost all individuals to move on land and after that to colonize other aquatic sites located nearby. Such terrestrial migrations allow survival in drying conditions without metamorphosis as long as the distances of terrestrial migration are short. These results are consistent with the presence of paedomorphs in drying ponds and are in favor of classic optimality models predicting metamorphosis in unfavorable environments. [less ▲]

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See detailHow Do Performance Measures Perform
Hübner, Georges ULg

in Journal of Portfolio Management (2007), 33(4), 64-74

The article presents a discussion on how various performance measures actually perform when used in investment portfolio management. The author discusses the empirical quality of performance measures such ... [more ▼]

The article presents a discussion on how various performance measures actually perform when used in investment portfolio management. The author discusses the empirical quality of performance measures such as information ratio (IR), focusing on directional managed portfolios, the Treynor ratio, and an empirical methodology that allows many of the usual errors associated with ratios to be avoided. The author also discusses multi-index models, style-based mutual funds, and style-adjusted performance. [less ▲]

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See detailHow do preschool teacher's requests influence children's behaviors ?
Crahay, Marcel ULg; Delhaxhe, Arlette

in Teaching & Teacher Education (1991), 7(3), 221-239

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See detailHow do Rhizobacterial Volatiles Influence Root System Architecture, Biomass Production and Allocation of the Model Grass Brachypodium distachyon?
Delaplace, Pierre ULg; Ormeño - Lafuente, Elena; Nguyen, Minh ULg et al

Conference (2016, January 12)

Plant growth-promoting rhizobacteria are increasingly considered as a complement of conventional inputs in agricultural systems. Their effects on their host plants are diverse and include volatile ... [more ▼]

Plant growth-promoting rhizobacteria are increasingly considered as a complement of conventional inputs in agricultural systems. Their effects on their host plants are diverse and include volatile-mediated growth enhancement. The present study aims at assessing the effects of bacterial volatile production on the biomass production and the root system architecture of Brachypodium distachyon (L.) Beauv. (line Bd-21). An in vitro experimental set-up allowing plant-bacteria interaction through the gaseous phase without any physical contact was used to screen 19 bacterial strains for their growth promotion ability over a 10-day cocultivation period. Using principal component analysis followed by hierarchical clustering and two-way analysis of variance, five groups of bacteria were defined and characterized based on their combined influence on biomass production and root system architecture. The observed effects range from unchanged to highly increased biomass production coupled with increased root length and branching. Primary root length was only increased by the volatile compounds emitted by Enterobacter cloacae JM22 and Bacillus pumilus T4. Overall, the most significant results were obtained with Bacillus subtilis GB03 which induced a 81% increase in total biomass and enhanced total root length, total secondary root length and total adventitious root length by 88, 196 and 473% respectively. The analysis of the emission kinetics of bacterial volatile organic compounds is underway and should lead to the identification of volatile compounds candidates responsible for the observed growth promotion effects. Taking into account the inherent characteristics of our in vitro system, the next experimental steps are identified and discussed from a fundamental and applied viewpoint. [less ▲]

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See detailHow do small and medium architectural firms deal with architectural complexity? A look into digital practices
Stals, Adeline ULg; Jancart, Sylvie ULg; Elsen, Catherine ULg

in Hentila, Helka-Liisa; Herneoja, Aulikki; Pihlajaniemi, Henrika (Eds.) et al Proceedings of te 34th eCAADe annual conference: Complexity and Simplicity (2016)

Digital design tools are nowadays deeply rooted in most architectural design processes. Either used as a way to communicate a designed artifact, or rather as a medium to test innovative morphologies ... [more ▼]

Digital design tools are nowadays deeply rooted in most architectural design processes. Either used as a way to communicate a designed artifact, or rather as a medium to test innovative morphologies (lately referred to as non-standard architecture), these design tools profoundly shape the way architects envision complexity all along their day-to-day tasks. The large teams of "star-architects" were able to develop dedicated and specific strategies and digital tools to overcome some of the technological gaps they were faced to when using commercial packages. But how are small and medium firms dealing with the inherent complexities of such software? This contribution analyzes how those firms (and more specifically the Walloon ones) deal with the growing complexity of digital tools, both in terms of use and interdisciplinarity. [less ▲]

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See detailHow do temperate bryophytes face the challenge of a changing environment? Lessons from the past and predictions for the future
Desamore, Aurélie ULg; Laenen, Benjamin ULg; Stech, M. B et al

in Global Change Biology (2012), 18(9), 2915-2924

Bryophytes are a group of early land plants, whose specific ecophysiological and biological features, including poikilohydry, sensitivity to moderately high temperature and high dispersal ability, make ... [more ▼]

Bryophytes are a group of early land plants, whose specific ecophysiological and biological features, including poikilohydry, sensitivity to moderately high temperature and high dispersal ability, make them ideal candidates for investigating the impact of climate changes. Employing a combined approach of species distribution modelling (SDM) and molecular phylogeography in the temperate moss Homalothecium sericeum, we explore the significance of the Mediterranean refugia, contrasting the southern and northern refugia hypotheses, determine the extent to which recolonization of previously glaciated areas has been facilitated by the high dispersal ability of the species and make predictions on the extent to which it will be impacted by ongoing climate change. The Mediterranean areas exhibit the highest nucleotidic diversities and host a mixture of ancestral, endemic and more recently derived haplotypes. Extra-Mediterranean areas exhibit low genetic diversities and Euro-Siberian populations display a significant signal of expansion that is identified to be of Euro-Siberian origin, pointing to the northern refugia hypothesis. The SDMs predict a global net increase in range size owing to ongoing climate change, but substantial range reductions in southern areas. Presence of a significant phylogeographical signal at different spatial scales suggests, however, that dispersal limitations might constitute, as opposed to the traditional view of spore-producing plants as efficient dispersers, a constraint for migration. This casts doubts about the ability of the species to face the massive extinctions predicted in the southern areas, threatening their status of reservoir of genetic diversity. © 2012 Blackwell Publishing Ltd. [less ▲]

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See detailHow do tumor cells interact with lymphatic endothelial cells?
Van De Velde, Maureen ULg

Conference (2014)

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See detailHow do we perceive vocal pitch accuracy during singing?
Larrouy, Pauline ULg; Pfordresher, Peter Q

Conference (2014, March 03)

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See detailHow do we understand Smart City? An Evolutionary Perspective
Crutzen, Nathalie ULg; Kummitha, Rama

Conference (2016, August 25)

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See detailHow do women entrepreneurs use the virtual network Facebook? The impact of gender
Constantinidis, Christina ULg

in International Journal of Entrepreneurship & Innovation (2011), 12(4), 257-269

This paper examines the views and attitudes of a sample of 228 female entrepreneurs towards the virtual social network Facebook. It identifies the main trends and uses statistical analysis to evaluate the ... [more ▼]

This paper examines the views and attitudes of a sample of 228 female entrepreneurs towards the virtual social network Facebook. It identifies the main trends and uses statistical analysis to evaluate the impact of their gendered sector of activity and of their self-perception on their view of this network as a response to gender-related difficulties and their use of it in relation to their activities and objectives. The study further investigates how Facebook may encourage and support women’s networks as well as benefit women-owned businesses. It highlights certain implications for public and private initiatives and underlines the potential of this and other virtual social networking sites for women’s entrepreneurship. [less ▲]

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See detailHow do “scoops” influence the perception of singing accuracy?
Larrouy, Pauline ULg; Pfordresher, Peter

Conference (2015, August)

When we listen to a singer, a large amount of time-varying information is available on which evaluations of accuracy may be based. Most analyses of singing accuracy focus on relatively steady portions of ... [more ▼]

When we listen to a singer, a large amount of time-varying information is available on which evaluations of accuracy may be based. Most analyses of singing accuracy focus on relatively steady portions of sung notes, eliminating “scoops” of pitch that often occur at note beginnings and endings. However, it is likely that these scoops contribute to judgments of accuracy. We report results of three experiments designed to address the relative contribution of these scoops in contrast to a steady central portion of sung notes. Participants rated the pitch accuracy of 4-tone melodies where the 3rd tone was manipulated with respect to its center region (either correct, 50 cents sharp, or 50 cents flat) as well as the presence of a scoop at the start and/or the end of the tone, varying with respect to direction. We were particularly interested in contrasting scoops that maintained ‘continuity’ between tones (e.g., scooping up for an ascending interval) versus those that highlighted distinctions (the opposite). Further analyses evaluated whether reactions to scoops indicate a tendency to perceive the average pitch across the entire tone, or to treat scoops versus the tone’s center as separate features. Results suggest that listeners respond to scoops in a way that goes beyond role in forming the average pitch across a tone. Listeners respond differently to scoops at the beginning versus the end, showing more sensitivity to ending scoops. Furthermore, listeners do not necessarily prefer scoops that preserve continuity. Taken together, these results demonstrate that continuous time-varying pitch information is an important indicator of perceived singing accuracy, and should be considered more fully when assessing singing ability. [less ▲]

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See detailHow does an ice block assembly melt?
Dorbolo, Stéphane ULg; Ludewig, François ULg; Vandewalle, Nicolas ULg et al

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2012)

Detailed reference viewed: 43 (18 ULg)
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See detailHow does cement augmentation increase the mechanical properties of trabecular bone?
Ruffoni, Davide ULg; Steiner, Juri; Wirth, Andreas et al

Conference (2011, January)

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See detailHow does dopamine regulate male sexual behavior : lessons from the birds
Cornil, Charlotte ULg; Balthazart, Jacques ULg; Ball, Gregory F.

Conference (2005, November 05)

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See detailHow does elicitor and antimicrobial fengycin interact with plasma membranes of sensitive cells ?
Nasir, Mehmet Nail ULg; Eeman, Marc; Lins, Laurence ULg et al

Conference (2012, April)

Fengycin is characterized by its strong antifungal and low hemolytic activities. It has also been recently demonstrated that it has plant elicitor properties and is also able to enhance the elicitors’ ... [more ▼]

Fengycin is characterized by its strong antifungal and low hemolytic activities. It has also been recently demonstrated that it has plant elicitor properties and is also able to enhance the elicitors’ activity of surfactin. The cell target of its biological activities is supposed to be plasma membrane. In spite of these interesting biological activities, fengycin has not been extensively investigated probably because of the difficulties related to its production. In a first time; we have characterized the interfacial properties of fengycin by tensiometry measurements and demonstrated that this surface activity was pH-dependent. In a second time; we have investigated the interactions of the lipopeptide with membrane lipids using model membranes such as Langmuir monolayers and multilammelar vesicles (MLVs). Our results indicate that the lipopeptide was able to penetrate into different lipid monolayers showing a preference for sterol-containing monolayers. In order to better understand the mechanism of the interactions of fengycin with membranes at the molecular level, MLVs with or without fengycin have been analyzed by spectroscopic techniques. We have shown that conformational changes of the lipopeptide occurred in the presence of lipids and they were more significant in the presence of sterol. Moreover, tyrosine residues of the lipopeptide seem to play an important role in these interactions. In conclusion, we have determined that the surface-active behavior as well as the conformation of fengycin depends on its environment. We have also showed that the lipopeptide does not interact with all class of lipids in the same way and presents a preference for sterols. The presence of key groups within peptide cycle has also been supposed for the biological activities of the lipopeptide. [less ▲]

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See detailHow does engagement in reading predict digital reading proficiency among 15 year-olds?
Lafontaine, Dominique ULg; Monseur, Christian ULg; Baye, Ariane ULg

Conference (2012, September)

In PISA 2009, 19 countries took part to an optional assessment of digital reading. In each country, a subsample of 15 year-olds was administered not only the paper and pencil PISA test, but also different ... [more ▼]

In PISA 2009, 19 countries took part to an optional assessment of digital reading. In each country, a subsample of 15 year-olds was administered not only the paper and pencil PISA test, but also different reading tasks online. The aim of our study is to investigate the relationships between engagement in reading, especially online reading practices, and digital reading proficiency of 15 year-olds in the 11 European countries which took part to this option (11 out of 19). [less ▲]

Detailed reference viewed: 78 (6 ULg)