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See detailWhat is the impact of ticket-level fare information on classic itinerary choice models ?
Lurkin, Virginie ULg; Garrow, Laurie; Schyns, Michael ULg

Scientific conference (2015, March 25)

I have been invited by Prof. Dr. Catherine Cleophas as an external guest to the "Revenue Management Colloquium" in Aix-la-Chapelle from March 25 to March 26. The aim is to present my own doctoral project ... [more ▼]

I have been invited by Prof. Dr. Catherine Cleophas as an external guest to the "Revenue Management Colloquium" in Aix-la-Chapelle from March 25 to March 26. The aim is to present my own doctoral project and discuss the presentations of other PhD students [less ▲]

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See detailPuissances émergentes : portée et limite d’un phénomène international
Santander, Sébastian ULg

Scientific conference (2015, March 25)

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See detailDetection of past and future atmospheric circulation changes over the North Atlantic region with the help of an automatic circulation type classification
Belleflamme, Alexandre ULg

Doctoral thesis (2015)

Future projections of the atmospheric circulation over the Northern Hemisphere high latitudes, especially the North Atlantic, have high uncertainties and some of the projected changes are opposed to ... [more ▼]

Future projections of the atmospheric circulation over the Northern Hemisphere high latitudes, especially the North Atlantic, have high uncertainties and some of the projected changes are opposed to circulation changes that have been observed since the 2000s. In this thesis, we focus on three particular aspects of the past and projected future summertime atmospheric circulation over the broader North Atlantic region. First, we analyse whether the 2007-2012 summertime anticyclonic anomaly over the Beaufort Sea, the Canadian Arctic Archipelago, and Greenland might rather be due to global warming or to the internal variability of the atmospheric circulation by putting it in perspective with the circulation variability over the last 150 years given by five reanalysis datasets. Then, this analysis is extended for the future circulation projected towards 2100 by CMIP3 and CMIP5 General Circulation Models (GCMs) over Greenland. Finally, we evaluate the impact of the uncertainties of the future atmospheric circulation projections on the mitigating or enhancing influence of the summertime circulation changes on temperature and precipitation over Europe. We use an automatic circulation type classification to analyse in detail the atmospheric circulation changes by grouping similar daily SLP (mean sea level pressure) or Z500 (500 hPa geopotential height) fields into homogeneous circulation types. It appears that the choice of the index, on the basis of which the days are grouped together, strongly influences the characteristics of the circulation types and the kinds of circulation changes that can be detected. In comparison with Euclidean distance and pressure gradient-based indices, correlation-based indices, especially the Spearman rank correlation, are the most suitable indices when focusing on the circulation pattern. Over the Arctic region, four periods with circulation anomalies similar to that of 2007-2012 (i.e. a summertime anticyclonic anomaly over the western Arctic region) have been detected over the last 150 years, despite a higher uncertainty of the circulation given by the reanalyses due to the scarcity of observational data before 1940. Nevertheless, the 2007-2012 anomaly appears to be exceptional and several connexions with other variables, such as the North Atlantic Oscillation index and sea ice loss, suggest that it could be part of a major climatic anomaly extending beyond the Arctic region. However, the occurrence of similar periods in the past and the influence of several external and internal forcings do not allow us to attribute it to global warming. The future summertime atmospheric circulation projected by GCMs over Greenland confirms this conclusion. In fact, no significant circulation pattern changes are simulated towards 2100, besides a generalised Z500 increase caused by the projected warming. Since GCMs are able to simulate atmospheric circulation changes over other regions and since the atmospheric circulation itself is influenced by other variables, such as sea ice or snow extent, which are already impacted by long-term changes, we conclude that the 2007-2012 anomaly could rather be attributed to the internal variability of the climatic system. Finally, we evidence that projected future atmospheric circulation changes impact on the SLP and precipitation changes simulated over Europe towards 2100 for summer. Over north-western Europe, these circulation changes could mitigate the SLP decrease by around 50 % and cancel out the precipitation increase. Nevertheless, high uncertainties among the GCMs on the magnitude and even on the sign of these changes cast doubt on the reliability of these projections. On the other hand, future atmospheric circulation changes are not projected to affect significantly the warming and drying simulated for the next decades over the Mediterranean region and eastern Europe. [less ▲]

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See detailLa pénétration africaine des émergents
Santander, Sébastian ULg

Scientific conference (2015, March 25)

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See detailCensure... Et la bande dessinée ?
Paques, Frédéric ULg; Pinelli, Joe

Conference given outside the academic context (2015)

Depuis son « âge d'or » dans les années 50, la bande dessinée a été une littérature particulièrement surveillée par les pouvoirs publics. Considérée comme une production destinée à la jeunesse, elle se ... [more ▼]

Depuis son « âge d'or » dans les années 50, la bande dessinée a été une littérature particulièrement surveillée par les pouvoirs publics. Considérée comme une production destinée à la jeunesse, elle se devait de rester dans les limites de la bienséance. Aux Etats-Unis, cela a donné lieu au début des années 50, à l'instauration du Comic's Code, appliqué par les grands éditeurs. En France, et donc indirectement en Belgique, la loi de 1949 sur les publications destinées à la jeunesse est toujours d'actualité. Quelle a été – quelle est toujours - l'influence réelle de ces règles ? Y'a-t-il d'autres formes de censure en bande dessinée ? C'est notamment de ces questions que traitera la conférence. [less ▲]

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See detailPlasma riche en plaquettes - PRP
Kaux, Jean-François ULg

Conference (2015, March 25)

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See detailFaut-il payer le train plus cher à l'heure de pointe ?
Gautier, Axel ULg

Article for general public (2015)

La semaine dernière, la presse faisait écho du projet de la SNCB d'introduire des tarifs plus élevés pour les voyages effectués à l'heure de pointe. Concrètement, celui qui prendrait le train dans les ... [more ▼]

La semaine dernière, la presse faisait écho du projet de la SNCB d'introduire des tarifs plus élevés pour les voyages effectués à l'heure de pointe. Concrètement, celui qui prendrait le train dans les tranches 6h-9h et 15h-18h paierait un supplément. La SNCB motive son projet par le fait que le prix actuel est un des plus faible d'Europe. La proposition a –comme on s'en doute- reçu un accueil glacial de la part des usagers du rail. Dans ce focus de Regards économiques, Axel Gautier livre les réflexions d'un économiste (qui est aussi navetteur) à propos de ce projet de la SNCB. [less ▲]

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See detailFormulations of the bed slope term in the shallow water equations: implication for energy balance
Bruwier, Martin ULg; Archambeau, Pierre ULg; Erpicum, Sébastien ULg et al

in Workshop on Advances in Numerical Modelling of Hydrodynamics (2015, March 24)

For an incompressible, isothermal, continuous and frictionless flow, the exact resolution of the equation of conservation of mechanical energy is equivalent to the exact resolution of the equation of ... [more ▼]

For an incompressible, isothermal, continuous and frictionless flow, the exact resolution of the equation of conservation of mechanical energy is equivalent to the exact resolution of the equation of momentum conservation. However, the discrete solution of the equation of momentum conservation does not verify the equation of energy conservation. This is particularly the case as a result of the presence of a non-conservative bed slope term in the equation of momentum conservation. In this research, the influence of (i) the formulation and (ii) the discretization scheme of the non-conservative bed slope term on the energy conservation is analysed in the case of a 1D horizontal and frictionless channel with a topographic step. The results for two different formulations of the bed slope term are firstly compared: the standard formulation of the bed slope source term and a divergence formulation of the bed slope term. Then, different discretization schemes of the divergence formulation of the bed slope term are analyzed to determine the one minimizing the numerical variation of energy. [less ▲]

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See detailL’impact de la lumière sur le cerveau
Vandewalle, Gilles ULg

Scientific conference (2015, March 24)

Detailed reference viewed: 13 (2 ULg)
See detailLutter contre les stéréotypes associés au vieillissement et à la maladie d’Alzheimer
Clesse, Audrey ULg; Schroyen, Sarah ULg

Conference given outside the academic context (2015)

Detailed reference viewed: 10 (0 ULg)
See detailPAESAGGI INCISI: Recupero, riuso, rigenerazione
Occhiuto, Rita ULg

Scientific conference (2015, March 24)

Detailed reference viewed: 8 (1 ULg)
See detailDiscovery of ultraviolet aurora on Mars’ Northern hemisphere
Stiepen, Arnaud ULg

Scientific conference (2015, March 24)

Detailed reference viewed: 1 (1 ULg)
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See detailAge-dependent expression of osteochondrosis-related genes in equine leukocytes
Mendoza García, Luis ULg; Piquemal, David; Lejeune, Jean-Philippe ULg et al

in Veterinary Record : Journal of the British Veterinary Association (2015), 2

Introduction: Osteochondrosis (OC) is a developmental disease in horses which has a significant impact on the horse’s welfare and performance. The early disturbance in the process of endochondral ... [more ▼]

Introduction: Osteochondrosis (OC) is a developmental disease in horses which has a significant impact on the horse’s welfare and performance. The early disturbance in the process of endochondral ossification progresses to inflammatory and repair processes in older horses. Previously, differentially expressed genes in leukocytes of OC-affected horses have been identified. The aim of the present study is to detect age-related changes in these differentially expressed genes. Materials and Methods: The expression of OC-related genes was analysed by real-time PCR and subsequent statistical analysis (ΔΔCT) in the leukocytes of 135 Belgian Warmblood horses divided into three different age groups: 30 months (n=38). Results: Relative expression of genes of horses less than 12 months of age showed significant induction of the genes MGAT4A, PRKCG, MHCI, ApoB, ApoB3G, B4GALT6 and a significantly lower expression of the genes OAS3. Horses of 18–24 months of age, showed a significantly higher expression of the genes TBC1D9, MGAT4A, IFIH1, MHCIIa and MMP1. Horses of more than 30 months of age showed a significantly higher expression of the genes MGAT4A, HP, SECTM1 compared with their age-matched control groups. Conclusions: The study demonstrates that OC-related genes are differentially expressed in horses of different ages compared with their age-matched controls. Some of the genes may be implicated in cell signalling and differentiation as well as carbohydrate and lipid metabolism and inflammation. However, the causal relationship between the differentially expressed genes and the development and progression of the OC lesions needs to be determined. [less ▲]

Detailed reference viewed: 10 (2 ULg)
See detailEnfants, témoins de violences conjugales : plus que des dommages collatéraux !
Garcet, Serge ULg

Article for general public (2015)

L'article aborde différentes considérations autour des conséquences pour l'enfant d'un environnement parental violent.

Detailed reference viewed: 23 (1 ULg)
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See detailPast changes in the vertical distribution of ozone – Part 3: Analysis and interpretation of trends
Harris, N. R. P.; Hassler, B.; Tummon, F. et al

in Atmospheric Chemistry & Physics Discussions (2015), 15(6), 8565--8608

Trends in the vertical distribution of ozone are reported and compared for a number of new and recently revised datasets. The amount of ozone-depleting compounds in the stratosphere (as measured by ... [more ▼]

Trends in the vertical distribution of ozone are reported and compared for a number of new and recently revised datasets. The amount of ozone-depleting compounds in the stratosphere (as measured by Equivalent Effective Stratospheric Chlorine – EESC) maximised in the second half of the 1990s. We therefore examine the trends in the periods before and after that peak to see if any change in trend is discernible in the ozone record. Prior to 1998, trends in the upper stratosphere (~ 45 km, 4 hPa) are found to be −5 to −10% per decade at mid-latitudes and closer to −5% per decade in the tropics. No trends are found in the mid-stratosphere (28 km, 30 hPa). Negative trends are seen in the lower stratosphere at mid-latitudes in both hemispheres and in the deep tropics. However it is hard to be categorical about the trends in the lower stratosphere for three reasons: (i) there are fewer measurements, (ii) the data quality is poorer, and (iii) the measurements in the 1990s are perturbed by aerosols from the Mt. Pinatubo eruption in 1991. These findings are similar to those reported previously even though the measurements for the two main satellite instruments (SBUV and SAGE II) and the ground-based Umkehr and ozonesonde stations have been revised. There is no sign of a continued negative trend in the upper stratosphere since 1998: instead there is a hint of an average positive trend of ~ 2% per decade in mid-latitudes and ~ 3% per decade in the tropics. The significance of these upward trends is investigated using different assumptions of the independence of the trend estimates found from different datasets. The averaged upward trends are significant if the trends derived from various datasets are assumed to be independent, but are generally not significant if the trends are not independent. This arises because many of the underlying measurement records are used in more than one merged dataset. At this point it is not possible to say which assumption is best. Including an estimate of the drift of the overall ozone observing system decreases the significance of the trends. The significance will become clearer as (i) more years are added to the observational record, (ii) further improvements are made to the historic ozone record (e.g. through algorithm development), and (iii) the data merging techniques are refined, particularly through a more rigorous treatment of uncertainties. [less ▲]

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See detailLe programme gouvernemental (2014-2019) en questions
Grandjean, Geoffrey ULg

Conference given outside the academic context (2015)

Detailed reference viewed: 20 (7 ULg)