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See detailUtilisation du D-galactose et du D-tagatose chez Bacillus sp.: Etude des protéines GalM et PBP4a de B. subtilis et B. amyloliquefaciens et Etude de la voie catabolique PTS-dépendante du D-tagatose chez B. licheniformis.
Van der Heiden, Edwige ULg

Doctoral thesis (2017)

Cette thèse s’intéresse à la métabolisation de deux sources de carbones, le galactose et le tagatose, dans des souches du genre Bacillus. La première partie de la thèse vise à montrer le rôle de GalM, une ... [more ▼]

Cette thèse s’intéresse à la métabolisation de deux sources de carbones, le galactose et le tagatose, dans des souches du genre Bacillus. La première partie de la thèse vise à montrer le rôle de GalM, une galactose mutarotase, dans la métabolisation du galactose chez B. subtilis ATCC 21332 et B. amyloliquefaciens FZB42. Le gène galM est organisé en opéron avec le gène dacC qui code pour un PBP de faible poids moléculaire, le PBP4a. Des mutants ponctuels et de délétion ont été générés dans le but d’étudier l’implication des produits de cet opéron dans la formation de biofilms in vitro, dans le remodelage de la paroi bactérienne et dans la colonisation de racines de plantes (plants de tomate et Arabidopsis thaliana). Une différence significative de colonisation a été mise en évidence entre la souche sauvage de B. amyloliquefaciens FZB42 et son double mutant uniquement sur les racines de plants de tomate. Toutefois, il pourrait s’agir d’un effet indirect lié à la méthode. Après analyse des muropeptides composant le peptidoglycane isolé en phase végétative, aucun rôle in vivo n’a pu être attribué au PBP4a. Cependant, l’attachement de cette protéine à la membrane de la bactérie a pu être mis en évidence. Une couronne de charges positives en surface du domaine II du PBP4a est responsable de cette localisation. La seconde partie de la thèse présente la voie de métabolisation du tagatose découverte chez B. licheniformis. Cette source de carbone est transportée et phosphorylée par les composants du système phosphotransférase (PTS) : EIIAT AG (TagM) et EIIBCT AG (TagL). La fonctionnalité du cluster de gènes identifié dans le génome de la bactérie a été démontrée par des expériences de supplémentation dans deux souches initialement incapables de métaboliser cette source de carbone : B. subtilis et E. coli. Le tagatose est phosphorylé durant son transport au niveau du carbone C1. Le tagatose-1-phosphate, présent principalement sous la forme -pyranose, est ensuite phosphorylé par l’enzyme TagK, une tagatose-1-phosphate kinase. Les paramètres cinétiques de l’enzyme ont été déterminés et la spécificité en faveur du tagatose-1-phosphate a été démontrée. Le tagatose 1,6-bisphosphate généré par TagK est hydrolysé en DHAP et G3P par GatY, une tagatose 1,6-bisphosphate aldolase de classe II. [less ▲]

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See detail4th Doctoral Seminar on Sustainability Research in the Built Environment Book of Abstracts
Attia, Shady ULg; Teller, Jacques ULg; Mahy, Grégory ULg

Book published by SBD Lab (2017)

The DS2BE is a joint initiative of research groups working on sustainability issues at 8 Belgian universities: ULBruxelles, VUBrussel, KULeuven, UCLouvain, ULiège, UHasselt, UAntwerpen and UGent ... [more ▼]

The DS2BE is a joint initiative of research groups working on sustainability issues at 8 Belgian universities: ULBruxelles, VUBrussel, KULeuven, UCLouvain, ULiège, UHasselt, UAntwerpen and UGent. Conceived as a platform for PhD researchers whose work engages the built environment at different scales in the framework of sustainability, these seminars provide an excellent opportunity for the doctoral students of the partner institutions to present their ongoing research. They will get feedback from a broad panel of sustainability experts, including invited specialists and peers, for furthering their research. PhD candidates can provide submissions that concern topics, such as: - Sustainable Architecture and Resources, materials, re-cycling /re-use, building elements and envelope, building physics, building construction technology, building renovation, drawing lessons from vernacular, bioclimatic design, regenerative design, biomimetic and integrated design, …, - Sustainability theory, sustainability / environmental assessment at building and neighborhood scales, and at the scale of city and regions, - Sustainable urbanism, urban form, landscape and urban ecology, urban green infrastructure and ecosystem services, public space, density, urban infrastructure & transportation, water urbanism, retrofitting of buildings to the built environment, - Methodologically oriented PhDs focusing on issues related to LCA (Life Cycle Analysis), I-O (Input-Output Analysis), MFA (Material Flow Analysis), simulation techniques, to exploring urban metabolism, industrial ecology, environmental modelling, GIS-based land-use change modelling, to Research by Design. [less ▲]

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See detailReconstructions of the 1900–2015 Greenland ice sheet surface mass balance using the regional climate MAR model
Fettweis, Xavier ULg; Box, Jason; Agosta, Cécile ULg et al

in Cryosphere (The) (2017), 11

With the aim of studying the recent Greenland ice sheet (GrIS) surface mass balance (SMB) decrease relative to the last century, we have forced the regional climate MAR (Modèle Atmosphérique Régional ... [more ▼]

With the aim of studying the recent Greenland ice sheet (GrIS) surface mass balance (SMB) decrease relative to the last century, we have forced the regional climate MAR (Modèle Atmosphérique Régional; version 3.5.2) model with the ERA-Interim (ECMWF Interim Re-Analysis; 1979–2015), ERA-40 (1958–2001), NCEP–NCARv1 (National Centers for Environmental Prediction–National Center for Atmospheric Research Reanalysis version 1; 1948–2015), NCEP–NCARv2 (1979–2015), JRA-55 (Japanese 55-year Reanalysis; 1958–2014), 20CRv2(c) (Twentieth Century Reanalysis version 2; 1900–2014) and ERA-20C (1900–2010) reanalyses. While all these forcing products are reanalyses that are assumed to represent the same climate, they produce significant differences in the MAR-simulated SMB over their common period. A temperature adjustment of +1 °C (respectively −1 °C) was, for example, needed at the MAR boundaries with ERA-20C (20CRv2) reanalysis, given that ERA-20C (20CRv2) is ∼ 1 °C colder (warmer) than ERA-Interim over Greenland during the period 1980–2010. Comparisons with daily PROMICE (Programme for Monitoring of the Greenland Ice Sheet) near-surface observations support these adjustments. Comparisons with SMB measurements, ice cores and satellite-derived melt extent reveal the most accurate forcing datasets for the simulation of the GrIS SMB to be ERA-Interim and NCEP–NCARv1. However, some biases remain in MAR, suggesting that some improvements are still needed in its cloudiness and radiative schemes as well as in the representation of the bare ice albedo. Results from all MAR simulations indicate that (i) the period 1961–1990, commonly chosen as a stable reference period for Greenland SMB and ice dynamics, is actually a period of anomalously positive SMB (∼ +40 Gt yr−1) compared to 1900–2010; (ii) SMB has decreased significantly after this reference period due to increasing and unprecedented melt reaching the highest rates in the 120-year common period; (iii) before 1960, both ERA-20C and 20CRv2-forced MAR simulations suggest a significant precipitation increase over 1900–1950, but this increase could be the result of an artefact in the reanalyses that are not well-enough constrained by observations during this period and (iv) since the 1980s, snowfall is quite stable after having reached a maximum in the 1970s. These MAR-based SMB and accumulation reconstructions are, however, quite similar to those from Box (2013) after 1930 and confirm that SMB was quite stable from the 1940s to the 1990s. Finally, only the ERA-20C-forced simulation suggests that SMB during the 1920–1930 warm period over Greenland was comparable to the SMB of the 2000s, due to both higher melt and lower precipitation than normal. [less ▲]

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See detailBlended learning - Pedagogical success factors and development methodology
Verpoorten, Dominique ULg; Parlascino, Emmanuelle ULg; André, Marine ULg et al

Report (2017)

Pedagogical factors that make a blended learning course a success are numerous. But the most critical one is, for blended courses owners, to rely on a safe development methodology. This is why this ... [more ▼]

Pedagogical factors that make a blended learning course a success are numerous. But the most critical one is, for blended courses owners, to rely on a safe development methodology. This is why this document presents as a handbook usable as a ready reference for guiding teachers through the different steps and attention points to be considered in the making of their blended set up. [less ▲]

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See detailThaw pond dynamics and carbon emissions in a Siberian lowland tundra landscape
Van Huissteden, J.; Heijmans, M.M.P.D.; Dean, J. et al

Poster (2017, April 25)

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See detailHow phosphorus limitation can control climatic gas sources and sinks
Gypens, N; Borges, Alberto ULg; Ghyoot, C

Poster (2017, April 25)

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See detailCattle grazing dynamics under contrasted pasture characteristics at temporal and spatial scales
Andriamandroso, Andriamasinoro ULg

Doctoral thesis (2017)

Grassland constitutes an important and a low-cost food source for grazing livestock. Optimal management should consider both forage resource productivity and animal needs. For cattle, grazing is a normal ... [more ▼]

Grassland constitutes an important and a low-cost food source for grazing livestock. Optimal management should consider both forage resource productivity and animal needs. For cattle, grazing is a normal behavior displayed in an attempt to eat the amount of forage to fulfill their nutritive requirements for maintenance and production. It is the most time-consumed activity of cows reared in pasture-based systems. With the increase of herd size, on one hand, farmers have been constrained to integrate innovative tools and techniques, such as milking robot, to improve the production system in particular to reduce the labor cost. On the other hand, such change might reduce time allocated for grazing on pasture. However pasture-based systems constitute a real pillar for sustainability as they are socially acceptable and environmentally profitable as they play an important role on ecosystem services and biodiversity provision. Studying grazing processes at individual level, which finally is the key point of animal-plant interactions, is a valuable research domain to enhance the knowledge about this mechanism and to feed decision support tools. This thesis aimed to link the changes in pasture characteristics to the grazing behavior of cattle in order to better understand the grazing strategy under different pasture characteristics and forage allowances. To allow an individual monitoring, sensor technology has integrated within farms and livestock researches to monitor many physical variables, inducing the emergence of precision livestock farming approach. Different types of sensors were designed, and already commercialized for some, primarily for physiological status detections such as heat, parturition or diseases. Grazing behaviors could be monitored using pressure, electromyography, acoustic or accelerometric sensors by classifying posture and movements of the animal into unitary behaviors (grazing, ruminating, resting, walking, etc.) and finer behavior such as chews and bites through jaw movements’ detection. When compared to real observation, detection accuracies of these behaviors were variable according to the type of sensor, its position on the animal during data acquisition on pasture, the data recording frequency, the time-window and the method dedicated to the post-recording data analysis. State-of-the-art analysis demonstrated a great performance of accelerometers for unitary behaviors and bites detection. An inertial measurement unit, integrating accelerometer, gyroscope and location sensors, was used for recording cattle movements during grazing at high sampling rate (100Hz). It allows a correct detection of grass intake and rumination behaviors with an average accuracy of 91% using 1-second time-window when calibrating and validating the detection algorithm. Deeper analysis of accelerometric signal allowed us to detect bites and chews performed during grazing and ruminating. Effects of pasture heights on grazing bites characteristics were differentiated by a higher frequency when pasture is at a lower height. Finally when combined to geographical information, a similar pattern was observed for cattle grazing on the same spot confirming their herd movement during grazing in terms of bites location. Differences were visible under different pasture heights but not significant. Such bites location, combined with continuous monitoring of cattle behaviors, through use of sensors, should be furtherly linked with more pasture characteristics, if possible with the same accuracy, and monitored on longer period in order to obtain a complete coverage of cattle grazing strategy and the effect of contrasted environment in order to purpose valuable tool for a better grazing management. [less ▲]

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See detailApport de l'ENMG aux syndromes douloureux diffus
WANG, François-Charles ULg

Scientific conference (2017, April 22)

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See detailHistoire d'une métropole industrielle dans l'entre-deux-guerres: Liège
Lanneau, Catherine ULg

Conference given outside the academic context (2017)

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See detailAnalyse spatiale intrasite basée sur un Système d'Information Géographique et appliquée aux vastes sites de plein air du Paléolithique moyen en France septentrionale. L’Exemple de Caours (Somme, France).
Moreau, Gwénaëlle ULg; Locht, Jean-Luc

Conference (2017, April 21)

Durant le Paléolithique moyen, l’alternance entre les périodes glaciaire et interglaciaire a rendu le peuplement de la France septentrionale discontinu. Cette région bénéficie d’un bon cadre ... [more ▼]

Durant le Paléolithique moyen, l’alternance entre les périodes glaciaire et interglaciaire a rendu le peuplement de la France septentrionale discontinu. Cette région bénéficie d’un bon cadre chronostratigraphique permettant l’étude des peuplements néandertaliens. Cependant certains aspects de leurs comportements restent encore mal caractérisés, particulièrement la fonction des sites reste souvent à préciser. L’étude de l’organisation spatiale intrasite apporte des éléments de réponse à ces questions. La fouille d’un site du Paléolithique moyen ne met pas directement en évidence l’organisation spatiale des lieux de vie, une modélisation est nécessaire pour la déceler. Nous avons donc débuté la construction d’un protocole d’analyse spatiale basé sur un Système d’Information Géographique et appuyé sur les sites de Caours. Ce site possède un rôle majeur de par sa superficie et l’excellente préservation des restes fauniques. Nous montrons ici l’existence d’une organisation spatiale sous forme de zones de concentration de vestiges en corrélant plusieurs méthodes – parmi lesquelles le K-mean Clustering et la Kernel Density Estimation. Nous préciserons ensuite la fonction de ces zones au sein d’un espace de vie et leur interaction entre elles au travers de la distribution spatiale des différents vestiges fauniques ou lithiques. [less ▲]

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See detailThe tax on legal entities in the light of civil law: a positive and prospective study of the income taxation for certain actors within the social economy
Garroy, Sabine ULg

Scientific conference (2017, April 21)

Dans le cadre de cette chaire Francqui, plusieurs doctorants belges ont eu l’occasion d’exposer leurs travaux et d’échanger avec le Pr. Dr. Dr.h.c. Wolfgang Schön, au cours de six classes d’excellence ... [more ▼]

Dans le cadre de cette chaire Francqui, plusieurs doctorants belges ont eu l’occasion d’exposer leurs travaux et d’échanger avec le Pr. Dr. Dr.h.c. Wolfgang Schön, au cours de six classes d’excellence dispensées à Liège et Anvers. [less ▲]

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See detailAnalyse Économique des Échanges Intra et Extracommunautaires de l'Union Économique et Monétaire Ouest-Africaine
Soma, Sassiémiké Abdoul Kader ULg

Doctoral thesis (2017)

Résumé de la thèse Le passage de l’Union Économique et Monétaire Ouest-Africaine (UEMOA) à une union douanière en janvier 2000 témoigne de la volonté des pays membres à promouvoir et à intensifier les ... [more ▼]

Résumé de la thèse Le passage de l’Union Économique et Monétaire Ouest-Africaine (UEMOA) à une union douanière en janvier 2000 témoigne de la volonté des pays membres à promouvoir et à intensifier les échanges commerciaux au sein de la zone. Plus de 15 ans après la création de ce vaste marché, les chiffres du commerce intra-communautaire ne sont guère encourageants. En effet, le ratio d’échanges intra-UEMOA stagne autour de 12%, nettement en dessous de ses échanges avec ses partenaires de l’UE et des 7 autres pays de la CEDEAO. La présente thèse a d’abord investigué le poids des barrières dans les échanges intra-UEMOA relativement à celles dans les échanges avec l’Europe et les autres pays de la CEDEAO. Les résultats montrent l’existence de plus de barrières dans les échanges avec l’UE et la CEDEAO que dans les échanges intra-UEMOA. Mieux, la faiblesse des échanges intra-communautaires doit être résorbée moins par la réduction des barrières dans les échanges mutuels que l’amélioration des facteurs d’offre et de demande. Ensuite, nous avons montré que la faiblesse des échanges intra-UEMOA est liée à leur mauvaise structure. En effet, les résultats montrent que les flux croisés de biens similaires entre pays de l’UEMOA sont faibles et leur augmentation permettrait non seulement de stimuler les échanges intra-communautaires, mais également de créer un effet multiplicateur du commerce sur la croissance. Enfin, après avoir analysé la dynamique de la croissance, du commerce et des investissements directs étrangers dans l’UEMOA, nous montrons que s’il existe une dynamique positive de long terme entre la croissance et le commerce, les IDE sont par contre défavorables à la croissance de long terme. Les recommandations vont dans le sens d’orienter davantage les IDE vers les secteurs de transformations capables de générer plus de productivité à long terme. [less ▲]

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See detailExpanding chemistry's horizon with continuous-flow reactors - part II
Monbaliu, Jean-Christophe ULg

Conference (2017, April 20)

Continuous-flow micro- and mesofluidic reactors come with inherent properties that can be advantageously utilized for expanding the horizon of synthetic organic chemistry. Accurate control over local ... [more ▼]

Continuous-flow micro- and mesofluidic reactors come with inherent properties that can be advantageously utilized for expanding the horizon of synthetic organic chemistry. Accurate control over local process parameters, even under extreme conditions, inherent safety, production homogeneity and seamless scale-up are amongst the most important assets of continuous-flow chemistry. Besides, flow chemistry enables the design of efficient multistep processes with significantly reduced footprints. In this lecture, we will discuss some of the most fascinating aspects of continuous-flow micro- and mesofluidic reactors in the specific context of preparative organic chemistry. Multiple examples illustrating the development and implementation of continuous-flow multistep strategies for the synthesis of high-value added organic targets will be presented. [less ▲]

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See detailMises en observation au départ d’un service d’urgences psychiatriques : Procédure, population et orientation.
Schmits, Emilie ULg; Evrard, Maude; Valassopoulou, Eftychia et al

Poster (2017, April 20)

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