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See detailCurrent and future atmospheric circulation at 500 hPa over Greenland simulated by the CMIP3 and CMIP5 global models
Belleflamme, Alexandre ULg; Fettweis, Xavier ULg; Lang, Charlotte ULg et al

in Climate Dynamics (2013), 41(7-8),

The Greenland ice sheet is projected to be strongly affected by global warming. These projections are either issued from downscaling methods (such as Regional Climate Models) or they come directly from ... [more ▼]

The Greenland ice sheet is projected to be strongly affected by global warming. These projections are either issued from downscaling methods (such as Regional Climate Models) or they come directly from General Circulation Models (GCMs). In this context, it is necessary to evaluate the accuracy of the daily atmospheric circulation simulated by the GCMs, since it is used as forcing for downscaling methods. Thus, we use an automatic circulation type classification based on two indices (Euclidean distance and Spearman rank correlation using the daily 500 hPa geopotential height) to evaluate the ability of the GCMs from both CMIP3 and CMIP5 databases to simulate the main circulation types over Greenland during summer. For each circulation type, the GCMs are compared to three reanalysis datasets on the basis of their frequency and persistence differences. For the current climate (1961–1990), we show that most of the GCMs do not reproduce the expected frequency and the persistence of the circulation types and that they simulate poorly the observed daily variability of the general circulation. Only a few GCMs can be used as reliable forcings for downscaling methods over Greenland. Finally, when applying the same approach to the future projections of the GCMs, no significant change in the atmospheric circulation over Greenland is detected, besides a generalised increase of the geopotential height due to a uniform warming of the atmosphere. [less ▲]

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See detailLong-term study of biogenic volatile organic compound exchanges in a forest ecosystem
Laffineur, Quentin ULg

Doctoral thesis (2012)

The terrestrial biosphere, especially forest ecosystems, emits large quantities of volatile organic compounds (VOCs) which have a significant impact on the atmosphere’s chemical and physical ... [more ▼]

The terrestrial biosphere, especially forest ecosystems, emits large quantities of volatile organic compounds (VOCs) which have a significant impact on the atmosphere’s chemical and physical characteristics. In particular, VOCs are precursors in the formation of ozone and sec-ondary organic aerosols. Isoprene and monoterpenes dominate the total VOC emissions, and methanol is one of the most abundant atmospheric VOCs due to its longer half-life than the other two. The main objective of this thesis was to investigate (using the eddy covariance technique and a proton-transfer-reaction mass spectrometer) the mechanisms of VOC (isoprene, monoterpene and methanol) emission and/or deposition at the scale of a temperate climate forest ecosystem (Vielsalm, Belgium) comprising several species (Fagus sylvatica, Abies alba, Picea Abies and Pseudotsuga menziessi). The eddy covariance technique is very suitable for studying VOC emission/deposition mechanisms at ecosystem level as it does not interfere with the functioning of the ecosystem and it has very good temporal resolution (half an hour). It was used for several months at the Vielsalm site without any major interruption to the measurements. The first measurement period ran from early July to late November 2009 and the second from late March to late November 2010. As well as measuring the VOC exchanges by eddy covari-ance, the climate parameters controlling the exchange mechanisms were also measured. During both these periods the methanol, acetaldehyde, acetone, isoprene, methyl vinyl ke-tone/methacrolein, monoterpene, acetic acid (2010) and formic acid (2010) fluxes were meas-ured. The highest emission levels observed were isoprene and monoterpenes along with methanol, which unlike the first two also showed depositions. The thesis therefore naturally focused on studying these three fluxes, in view of the important role played by these three compounds in atmospheric chemistry and hence the scientific community’s interest in refining the parametrisation of these compounds’ ecosystem/atmosphere exchange models. The study of the isoprene, monoterpene and methanol fluxes has been written up in three original articles which form the main body of this thesis. Because of the heterogeneity of the ecosystem studied, the first essential study concerned the identification of VOC-emitting species. This was done with the aid of a flux footprint model combined with a map of the species occurring on the site. This analysis showed that the main monoterpene emitter was Fagus sylvatica followed, to a lesser extent, by Abies alba, Picea Abies and Pseudotsuga menziessi. In contrast to the literature, the analysis showed Abies alba to be a probable isoprene emitter but the presence of Picea Abies, a known isoprene emitter, ruled out absolute certainty on that point. The isoprene fluxes were observed by day only, unlike the monoterpene fluxes which were observed both day and night. Diurnal flux analysis clearly showed temperature and light to be the two main variables controlling emissions. Combining this analysis with a study of the close relationship between isoprene/monoterpene emissions and photosynthesis revealed the plants’ de novo biosynthetic production mechanisms, an original aspect at ecosystem scale. From the occurrence of nocturnal monoterpene emissions it was possible to determine that de novo monoterpene production emitted directly into the atmosphere (as in the case of isoprene) was not the only source of the emissions observed. Withdrawals from monoterpene sinks located in plant organs or in the soil can also be monoterpene sources. Studying the relationship between isoprene/monoterpene fluxes and light, distinguishing between cloudy and sunny conditions, showed that for the same light intensity the emissions were higher in cloudy con-ditions than in sunshine. Similarly, a study of the relationship between isoprene fluxes and photosynthesis in cloudy/sunny conditions suggested that de novo isoprene production is greater in leaves above the canopy than in leaves within the canopy. Long-term measurement of isoprene and monoterpene emissions enabled seasonal changes in the mechanisms observed to be studied and more fully understood. As well as providing an understanding of the mechanisms, this research also resulted in quantification of the seasonal changes in the key parameters for modelling isoprene/monoterpene emissions. Methanol exchanges were generally positive (emissions) by day and negative (depositions) at night. Overall, methanol depositions were predominant in summer and autumn but in the mi-nority in spring. On average, the Vielsalm site behaved like a methanol sink, which contradicts all the other research published to date. An original model was developed for identifying the mechanisms responsible for short-term and long-term methanol emissions/depositions. The consistency between the measurements and the model simulations suggested that the main processes controlling methanol exchanges in summer could be attributed, in the short term, to (water-soluble) methanol adsorption/desorption occurring in the films of water on leaf surfaces and/or on the soil surface and, in the long term, to methanol destruction by a biological and/or chemical degradation process also occurring on the surface of leaves and/or the soil. A study of the difference between the measurements and the model, in spring, indicated the possibility of biosynthetic methanol production by the plants. This production was apparently controlled mainly by temperature, but it could not be shown in summer when methanol adsorption/desorption processes dominated. The literature on ecosystem-atmosphere exchanges of isoprene, monoterpenes and, to a lesser extent, methanol is extensive. Nevertheless, what makes this research original is the spatio-temporal scale used. We are in fact working at ecosystem scale, and not at leaf or branch scale as in most other cases. Moreover, our measurements cover a timescale from half an hour to a full growing season, which is rarely found in the literature. This has resulted in a better under-standing of these compounds’ production and exchange mechanisms. To be precise, the methanol flux study is currently unique in its description and understanding of the deposition mechanisms. [less ▲]

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See detailComment les parents peuvent-ils soutenir le développement langagier de leur enfant ?
Maillart, Christelle ULg

Conference given outside the academic context (2012)

Les caractéristiques du langage adressé à l’enfant influencent l’acquisition langagière tant pour les enfants présentant un développement normal du langage que pour ceux qui ont des troubles langagiers ... [more ▼]

Les caractéristiques du langage adressé à l’enfant influencent l’acquisition langagière tant pour les enfants présentant un développement normal du langage que pour ceux qui ont des troubles langagiers. Mais, pour ces derniers, le bénéfice lié à un input optimal est plus important que chez les enfants sans trouble. Malheureusement, en raison même du retard de développement du langage, l’ajustement du langage de l’adulte à l’enfant est rendu plus difficile. Il est en effet difficile de poursuivre une conversation si un des interlocuteurs parle peu voire pas. On se trouve alors dans une spirale négative : les enfants fragiles au niveau langagier dépendent plus que leurs pairs de la qualité de l’input qui leur est proposé et, à cause de leurs difficultés langagières, ils suscitent des interactions moins riches et moins à même de les soutenir dans leur développement langagier ultérieur. On peut néanmoins enrayer cette spirale négative en aidant les parents à retrouver un rôle d’acteur principal dans le développement langagier de leur enfant. Des stratégies simples spontanément utilisées par les parents lorsque tout se met en place naturellement peuvent être entrainées pour donner des occasions de communiquer, en suivant les intérêts de l’enfant, en le plaçant dans des routines prévisibles et familières, et en lui fournissant un langage plus adapté à ses difficultés. Ces stratégies sont les suivantes: 1) les stratégies centrées sur l’enfant (par exemple, se mettre au niveau de l’enfant, attendre que l’enfant initie l'interaction) ; 2) les stratégies de promotion de l’interaction (par exemple, encourager l’enfant à prendre leur tour dans une interaction, à poser des questions) ; 3) les stratégies de modelage du langage (par exemple, l’expansion, la reformulation, etc). [less ▲]

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See detailExperimental study and modeling the behavior of a solar water heater tested at the regions of Adrar, Algeria
Bennaceur, Said; Draoui, Belkacem; Benhamoun, Mohamed et al

in International Journal of Advanced Renewable Energy Research (2012), 1(8), 460-466

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See detailAn overview on application of exergy and energy for determination of solar drying efficiency
Bennamoun, Lyes ULg

in International Journal of Energy Engineering (2012), 2(5), 184-194

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See detailFigures et représentations de la Vierge Marie à l’épreuve de l’histoire des femmes
Henneau, Marie-Elisabeth ULg

in Henneau, Marie-Elisabeth; Delville, Jean-Pierre; Famerée, Joseph (Eds.) Marie figures et réceptions. Enjeux historiques et théologiques (2012)

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See detailPouvoirs d'abbesses et abbesses au pouvoir dans l'Ordre de Cîteaux. Quelques cas de figures aux Pays-Bas et en Principauté de Liège à l'aube de la Renaissance
Henneau, Marie-Elisabeth ULg

in Bousmar, Éric; Dumont, Jonathan; Marchandisse, Alain (Eds.) et al Femmes de pouvoir, femmes politiques durant les derniers siècles du Moyen Âge et au cours de la première Renaissance (2012)

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See detailMarie Figures et réceptions. Enjeux historiques et théologiques
Henneau, Marie-Elisabeth ULg; Delville, Jean-Pierre; Famerée, Joseph

Book published by Mame-Desclée (2012)

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See detailConclusions: Réceptions plurielles sur le long terme
Henneau, Marie-Elisabeth ULg

in Henneau, Marie-Elisabeth; DELVILLE, Jean-Pierre; Famerée, Joseph (Eds.) Marie figures et réceptions. Enjeux historiques et théologiques (2012)

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See detailEvolution des populations de coccinelles indigènes et de l’espèce exotique, Harmonia axyridis (Pallas), en Wallonie et en région de Bruxelles-Capitale
Durieux, Delphine ULg; Vandereycken, Axel ULg; Joie, Emilie ULg et al

in Entomologie Faunistique = Faunistic Entomology (2012), 65

An inventory of the Coccinellidae present in the collection of the Department of functional and evolutionary Entomology (ULg - Gembloux Agro-Bio Tech) was performed on the period extending from 2001 to ... [more ▼]

An inventory of the Coccinellidae present in the collection of the Department of functional and evolutionary Entomology (ULg - Gembloux Agro-Bio Tech) was performed on the period extending from 2001 to 2009. This collection is essentially made up of insects collected by first year students. The aim of this work is to assess the evolution of the species belonging to this family with special interest in their relative amount and the species richness. This study was focused on the data from Wallonia and Brussels-Capital Region (Belgium), not enough insects having been collected in Flanders. Among the identified individuals, 27 species were observed, including 21 belonging to the subfamily of Coccinellinae, 2 to Epilachninae and 4 to Chilocorinae. Most of the species are native to Belgium. However, Harmonia axyridis (Pallas 1773), an exotic species coming from the South-East of Asia, was introduced in Belgium in 1997. This alien ladybird was firstly collected by the students in 2002 and the amount of collected individuals does not cease increasing until 2009. By contrast, a decrease of species richness, as well as the relative amount of Adalia bipunctata (L. 1758), Propylea quatuordecimpunctata (L. 1758) and Psyllobora vigintiduopunctata (L. 1758), is highlighted. The link between these evolutions is discussed. [less ▲]

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See detailFermentative hydrogen production from glucose and starch using pure strains and artificial co-cultures ofClostridium spp.
Masset, Julien; Calusinska, Magdalena ULg; Hamilton, Christopher et al

in Biotechnology for biofuels (2012), 5(1), 35

ABSTRACT: BACKGROUND: Pure bacterial strains give better yields when producing H2 than mixed, natural communities. However the main drawback with the pure cultures is the need to perform the fermentations ... [more ▼]

ABSTRACT: BACKGROUND: Pure bacterial strains give better yields when producing H2 than mixed, natural communities. However the main drawback with the pure cultures is the need to perform the fermentations under sterile conditions. Therefore, H2 production using artificial co-cultures, composed of well characterized strains, is one of the directions currently undertaken in the field of biohydrogen research. RESULTS: Four pure Clostridium cultures, including C. butyricum CWBI1009, C. pasteurianum DSM525, C. beijerinckii DSM1820 and C. felsineum DSM749, and three different co-cultures composed of (1) C. pasteurianum and C. felsineum, (2) C. butyricum and C. felsineum, (3) C. butyricum and C. pasteurianum, were grown in 20 L batch bioreactors. In the first part of the study a strategy composed of three-culture sequences was developed to determine the optimal pH for H2 production (sequence 1); and the H2-producing potential of each pure strain and co-culture, during glucose (sequence 2) and starch (sequence 3) fermentations at the optimal pH. The best H2 yields were obtained for starch fermentations, and the highest yield of 2.91 mol H2/ mol hexose was reported for C. butyricum. By contrast, the biogas production rates were higher for glucose fermentations and the highest value of 1.5 L biogas/ h was observed for the co-culture (1). In general co-cultures produced H2 at higher rates than the pure Clostridium cultures, without negatively affecting the H2 yields. Interestingly, all the Clostridium strains and co-cultures were shown to utilize lactate (present in a starch-containing medium), and C. beijerinckii was able to re-consume formate producing additional H2. In the second part of the study the co-culture (3) was used to produce H2 during 13 days of glucose fermentation in a sequencing batch reactor (SBR). In addition, the species dynamics, as monitored by qPCR (quantitative real-time PCR), showed a stable coexistence of C. pasteurianum and C. butyricum during this fermentation. CONCLUSIONS: The four pure Clostridium strains and the artificial co-cultures tested in this study were shown to efficiently produce H2 using glucose and starch as carbon sources. The artificial co-cultures produced H2 at higher rates than the pure strains, while the H2 yields were only slightly affected. [less ▲]

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See detailIde de Louvain
Henneau, Marie-Elisabeth ULg

E-print/Working paper (2011)

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See detailIde de Nivelles
Henneau, Marie-Elisabeth ULg

E-print/Working paper (2011)

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See detailPour Annecy et pour le monde. L'ordre de la Visitation (1610-2010)
Henneau, Marie-Elisabeth ULg; Vismara, Paola; Barbiche, Bernard et al

Book published by SilvanaEditoriale (2011)

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See detailCorps sous le voile à l’Époque moderne
Henneau, Marie-Elisabeth ULg

in Mc Clive, Cathy; Pellegrin, Nicole (Eds.) Femmes en fleurs, femmes en corps. Sang, santé, sexualités du Moyen Âge aux Lumières (2010)

Il se raconte bien des histoires de corps dans les couvents de femmes au XVIIe siècle. Le corps y est associé à tous les événements de la vie religieuse : célébration des offices, exercices spirituels ... [more ▼]

Il se raconte bien des histoires de corps dans les couvents de femmes au XVIIe siècle. Le corps y est associé à tous les événements de la vie religieuse : célébration des offices, exercices spirituels, pratiques dévotionnelles, pour lesquels son rôle est défini avec précision. On ne cesse de statuer à son propos lorsqu’il est question de sa réfection, de son repos, de sa participation à la vie communautaire. Il entre en jeu dans tous les instants de ces vies consacrées, certes induites à se tourner vers le Ciel, mais aussi très inscrites au cœur des contingences terrestres. Pour suivre l’itinéraire de ces femmes, depuis leur plus tendre enfance jusqu’à leur dernier souffle, il sera fait appel, dans cet essai de synthèse, à un certain nombre de biographies spirituelles, les unes finalisées par l’entourage, souvent masculin, en vue d’une publication et donc adaptées aux exigences des instances qui les ont autorisées, les autres, réalisées par les religieuses à l’intention de leurs proches et donc plus spontanées et souvent inédites. Ces écrits, confrontés aux archives de la pratique, à la législation en usage et aux propos spirituels contemporains, permettront d’approcher la manière dont s’envisage et se raconte le corps des cloîtrées au XVIIe siècle, en tant qu’unité distincte, mais aussi comme élément toujours solidaire de l’âme. [less ▲]

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See detailFemmes et religions du livre
Henneau, Marie-Elisabeth ULg

Article for general public (2009)

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See detailRituels, cérémoniaux et coutumiers à l'usage de moniales cisterciennes et d'annonciades célestes du pays de Liège (17e-18e siècles)
Henneau, Marie-Elisabeth ULg

in Davy-Rigaux, Cécile; Dompnier, Bernard; Hurel, Odon (Eds.) Les cérémoniaux catholiques en France. Une littérature de codification des rites liturgiques (2009)

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See detailLe supériorat au féminin au temps de la Réforme catholique : conception et exercice du pouvoir dans quelques couvents de religieuses à vœux solennels
Henneau, Marie-Elisabeth ULg

in Santinelli, Emmanuelle; Dubois-Nayt, Armel (Eds.) Femmes de pouvoir et pouvoir de femmes dans l’Europe occidentale médiévale et moderne (2009)

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See detailMarie Dauvaine
Henneau, Marie-Elisabeth ULg

E-print/Working paper (2008)

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