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See detailEvolution of striatal metabolic and biochemical dysfunction in striato-nigral degeneration (SND).
Salmon, Eric ULiege; Sadzot, Bernard ULiege; Maquet, Pierre ULiege et al

in Journal of Neurology (1994), 241(S1), 36

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See detailEvolution of the Antarctic surface mass balance by high-resolution downscaling and impact on sea-level change for the next centuries
Agosta, Cécile ULiege; Favier, Vincent; Krinner, Gerhard et al

Conference (2012, July)

Most of the IPCC-AR4 Atmospheric Global Circulation Models (AGCM) predict an increase of the Antarctic Surface Mass Balance (SMB) during the 21st century that would mitigate global sea level rise. Present ... [more ▼]

Most of the IPCC-AR4 Atmospheric Global Circulation Models (AGCM) predict an increase of the Antarctic Surface Mass Balance (SMB) during the 21st century that would mitigate global sea level rise. Present accumulation and predicted change are largest at the ice sheet margins because they are driven by snowfall, which mostly comes from warm, moist air arising over the land slopes. The coastal belt is also where complex processes of sublimation, melt and refreezing occur. Thus, high-resolution modelling is necessary to adequately capture the effects of small-scale variations in topography on the atmospheric variables in this area, but limitations in computing resources prevent such resolution at the scale of Antarctica in full climate models. We present here a downscaling method leading to 15-km SMB resolution for century time-scales over Antarctica. We compute the effect of the fine topography on orographic precipitation and on boundary layer processes that lead to sublimation, melt and refreezing. We first display the SMB downscaled from ERA-Interim and show that the downscaling improves the agreement between modelled and observed SMB for the end of the 20th century. We then present hi-resolution features of the Antarctic SMB evolution during the 21st century downscaled from LMDZ4 for different scenarios. We show that a higher resolution induce at the same time more run-off but a significantly higher mitigation of sea level rise. [less ▲]

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See detailEvolution of the clinical expression of Bluetongue in Belgian cattle during year 2006 vs 2007
Guyot, Hugues ULiege; Mauroy, Axel ULiege; Rollin, Frédéric ULiege et al

Conference (2008)

In August 2006, Belgium notified its first cases of Bluetongue (BT), serotype 8, in cattle and sheep. The disease was also observed at this time in the neighboring countries. The resurgence of BT was ... [more ▼]

In August 2006, Belgium notified its first cases of Bluetongue (BT), serotype 8, in cattle and sheep. The disease was also observed at this time in the neighboring countries. The resurgence of BT was observed in Northern Europe in 2007. The aim of the study was to compare clinical signs of BT observed in 2006 vs 2007 in Belgian cattle. The description of clinical signs was based on the observation of 38 and 39 cows in 2006 and 2007, respectively. BT cases were only included if they were confirmed by one or both laboratory diagnostic tests (competitive ELISA test and/or RT-qPCR). The inventory of clinical signs was made with a standardised clinical form for BT. This form is divided into general, cutaneous, locomotor, digestive, respiratory, neurological and reproductive clinical signs. Case data were summarised to determine changes in clinical presentation of BT between 2006 and 2007. A Fischer’s exact probability test was performed to compare (P<0.05) the frequency of clinical signs between the two years. Regarding general clinical signs, hyperthermia and tiredness were more often observed in 2007, compared to 2006. All clinical signs about skin and annexes were not significantly different between the two years. Locomotor signs such as prostration, incapacity to get up, reluctance to move, lameness and amyotrophy were more frequent in 2007. Loss of appetite, difficulties in grasping feed, salivation and drooling were the digestive signs more often observed in 2007. A purulent nasal discharge was the only respiratory sign more commonly observed in 2007. Apathy, generalised weakness and paresis or paralysis were more often encountered in 2007. The most important changes between the two years concerned reproduction. A higher incidence of abortion, premature calving and stillbirth was observed during 2007 outbreak. The frequency of most of the clinical signs of BT was higher in 2007 in Belgian cattle. Confirmed cases of BT in Belgian cattle were only 296 in 2006 compared to 4187 in 2007. These data do not represent the real situation of BT infection because the farmers do not notify all cases. Nevertheless, it seems that the 2007 outbreak was more severe regarding the number of cases and the frequency of clinical signs. The mild winter and wet 2007 summer might have favored the persistence of the vectors. [less ▲]

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See detailEvolution of the content of THC and other major cannabinoids in drug-type cannabis cuttings and seedlings during growth of plants
DE BACKER, Benjamin ULiege; Maebe, Kevin; Verstraete, Alain G. et al

in Journal of Forensic Sciences (2012), 57(4), 918-922

In Europe, authorities frequently ask forensic laboratories to analyze seized cannabis plants to prove that cultivation was illegal (drug type and not fiber type). This is generally done with mature and ... [more ▼]

In Europe, authorities frequently ask forensic laboratories to analyze seized cannabis plants to prove that cultivation was illegal (drug type and not fiber type). This is generally done with mature and flowering plants. However, authorities are often confronted with very young specimens. The aim of our study was to evaluate when the chemotype of cannabis plantlets can be surely determined through analysis of eight major cannabinoids content during growth. Drug-type seedlings and cuttings were cultivated, sampled each week, and analyzed by high-performance liquid chromatography with diode array detection. The chemotype of clones was recognizable at any developmental stage because of high total Delta-9-tetrahydrocannabinol (THC) concentrations even at the start of the cultivation. Conversely, right after germination seedlings contained a low total THC content, but it increased quickly with plant age up, allowing chemotype determination after 3 weeks. In conclusion, it is not necessary to wait for plants’ flowering to identify drug-type cannabis generally cultivated in Europe. [less ▲]

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See detailEvolution of the early Earth biosphere
Javaux, Emmanuelle ULiege

Conference (2005)

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See detailEvolution of the effectiveness of stone bunds and trenches in reducing runoff and soil loss in the semi-arid Ethiopian highlands
Taye, G.; Poesen, J.; Vanmaercke, Matthias ULiege et al

in Zeitschrift für Geomorphologie (2015), 59(4), 477-493

Soil and Water Conservation (SWC) structures, in particular stone bunds and conservation trenches, have been extensively installed in Tigray since the 1980's. As the effectiveness of stone bunds and ... [more ▼]

Soil and Water Conservation (SWC) structures, in particular stone bunds and conservation trenches, have been extensively installed in Tigray since the 1980's. As the effectiveness of stone bunds and trenches in reducing runoff and soil loss depends on their retention capacities, it can be expected that this effectiveness declines over time due to infilling with sediment. However, little is known about the rate of this decline during subsequent years. We therefore assessed the effectiveness of SWC structures for two land use types, three slope classes and during three consecutive rainy seasons. Rainfall, runoff and soil loss were measured using 21 large (600-1,000m2) runoff plots at Mayleba catchment. Results show that all studied SWC structures are more effective in reducing soil loss than runoff. Conservation trenches are generally more effective in reducing runoff and soil loss than stone bunds. However, due to their infilling with sediment, their effectiveness quickly declines over time. By the end of the third rainy season, their effectiveness was reduced to about one third of their initial effectiveness. The effectiveness of stone bunds remained fairly constant during three consecutive rainy seasons. These findings have important implications, as they demonstrate that many of the installed SWC structures (especially in rangelands) are only very effective for short periods (one to two years). Regular sediment removal from conservation trenches is therefore crucial to preserve their effectiveness over longer periods. © 2014 Gebr. Borntraeger Verlagsbuchhandlung, Stuttgart, Germany. [less ▲]

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See detailThe evolution of the Fair Trade organisational landscape in France and in Belgium
Huybrechts, Benjamin ULiege

Conference (2008, May 14)

Parallel to the dramatic growth of its sales and public awareness, the Fair Trade movement has seen its organisational landscape become increasingly diversified. While Fair Trade nonprofit pioneers were ... [more ▼]

Parallel to the dramatic growth of its sales and public awareness, the Fair Trade movement has seen its organisational landscape become increasingly diversified. While Fair Trade nonprofit pioneers were initially relatively homogeneous in terms of goals and structures, the economic development of the initiative, driven by the sales of Fair Trade products in mainstream distribution channels, has led to the emergence of a multitude of new actors with much more heterogeneous behaviours – in spite of the general trend towards a stronger market orientation – (Gendron, 2004; Moore, 2004; Nicholls & Opal, 2005; Renard, 2003). When observing the evolution of Fair Trade organisations (FTOs), i.e., organisations claiming to be totally dedicated to Fair Trade, three trends can be observed: Fair Trade pioneers have adopted more business-oriented profiles and more complex and specialised organisational structures; New small Fair Trade businesses have emerged with a stronger economic specialisation on a particular product or distribution channel ; « Old » and « new » FTOs increasingly gather into networks with two types of purposes: to promote Fair Trade and to have a minimum political representation (advocacy networks) and to face common socio-economic challenges (socio-economic networks). The goal of this contribution is to analyse these three trends with the help of a sample of nearly fourty FTOs in Belgium and in the French Rhône-Alpes region. We can thus illustrate the three trends on the basis of both general observations and precise examples. We also try to compare the two regions and to explore to what extent the evolution of FTOs reveals more global trends within the Fair Trade movement. [less ▲]

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See detailThe evolution of the inorganic fluorine budget since the mid-1980s based on FTIR measurements at northern mid-latitudes
Duchatelet, Pierre ULiege; Feng, Wuhu; Chipperfield, Martyn et al

in Geophysical Research Abstracts (2011)

Fluorine enters the stratosphere principally in the form of CFCs (chlorofluorocarbons, mainly CFC-12 and CFC-11), HCFCs (hydrochlorofluorocarbons, mainly HCFC-22) and HFCs (hydrofluorocarbons, mainly HFC ... [more ▼]

Fluorine enters the stratosphere principally in the form of CFCs (chlorofluorocarbons, mainly CFC-12 and CFC-11), HCFCs (hydrochlorofluorocarbons, mainly HCFC-22) and HFCs (hydrofluorocarbons, mainly HFC-134a) which have been (or are still) widely emitted at ground level by human activities. In the lower stratosphere, the photolysis of these halogenated source gases leads to the formation of the two fluorine reservoirs COClF and COF2. The subsequent photolysis of these two compounds frees F atoms, which principally react with CH4 and H2O to form the extremely stable HF gas, by far the dominant fluorine reservoir in the middle and upper stratosphere. Despite the fact that fluorine does not significantly contribute in stratospheric ozone depletion, measurements of the concentrations of individual F-containing species in different altitude ranges of the atmosphere are important as they reflect the amounts of anthropogenic gases transported into the middle atmosphere as well as their decomposition. Such measurements also provide insight into the partitioning between major fluorine source gases (which are potent greenhouse gases) and reservoirs and allows a global inventory of organic (CFy), inorganic (Fy) and total (FTOT) fluorine burdens to be monitored as a function of time. Indeed, regular updates of such inventories are important as the partitioning between F-containing gases in the stratosphere is continually evolving as emissions of anthropogenic gases from the surface change, principally as a consequence of the progressive ban on the production of CFCs and HCFCs adopted by the Montreal Protocol and its subsequent Amendments and Adjustments. To complement recent studies regarding fluorine species (Duchatelet et al., 2009, 2010, 2011; Mahieu et al., 2011), this communication presents the time series of the inorganic fluorine budget Fy over the last twenty-five years, based on HF and COF2 total column amounts derived from high resolution Fourier transform infrared (FTIR) solar spectra recorded at Jungfraujoch (46.5°N, 8.0°E, 3580m asl). A trend analysis of our HF, COF2 and Fy time series is performed and discussed in the context of past and current emissions of halogenated source gases. Comparisons with model and space data are also included. [less ▲]

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See detailEvolution of the Io footprint brightness I: Far-UV observations
Bonfond, Bertrand ULiege; Hess, Sébastien; Gérard, Jean-Claude ULiege et al

in Planetary and Space Science (2013), 88

The Io footprint (IFP) is a set of auroral spots and an extended tail resulting from the strong interaction between Io and the Jovian magnetosphere. For the first time, we present measurements of the ... [more ▼]

The Io footprint (IFP) is a set of auroral spots and an extended tail resulting from the strong interaction between Io and the Jovian magnetosphere. For the first time, we present measurements of the brightness and precipitated power for each individual spot, using the image database gathered from 1997 to 2009 with the Hubble Space Telescope in the Far-UV domain. We show that the relative brightness of the spots varies with the System III longitude of Io. Moreover, our novel measurement method based on 3D simulations of the auroral features allows to derive the precipitated energy fluxes from images on which the emission region is observed at a slant angle. Peak values as high as 2 W/m² are observed for the main spot, probably triggering a localized and sudden heating of the atmosphere. Additionally, strong brightness differences are observed from one hemisphere to another. This result indicates that the location of Io in the plasma torus is not the only parameter to control the brightness, but that the magnetic field asymmetries also play a key role. Finally, we present new data confirming that significant variations of the spots' brightness on timescales of 2-4 minutes are ubiquitous, which suggests a relationship with intermittent double layers close to Jovian surface. [less ▲]

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See detailEvolution of the Io Footprint Brightness II: Modeling
Hess, Sébastien; Bonfond, Bertrand ULiege; Chantry, Virginie ULiege et al

in Planetary and Space Science (2013), 88

The interaction of Io with the Jovian magnetosphere creates the best known and brightest satellite-controlled aurorae in our solar system. These aurorae are generated by the precipitation of electrons ... [more ▼]

The interaction of Io with the Jovian magnetosphere creates the best known and brightest satellite-controlled aurorae in our solar system. These aurorae are generated by the precipitation of electrons, which are accelerated by the Alfvén waves carrying the current between the satellite and the planet. A recent study computed the energy deposited on top of Jupiter's ionosphere due to the electron precipitation and retrieved the correct mean brightness of Io-related aurorae. The model developed in this study takes into account the acceleration mechanism and the Alfvén wave propagation effects. We use the same method to investigate the brightness variation of the different components of the Io footprint as a function of longitude. These observations are discussed in a companion paper. We identify several effects that act together to modulate the footprint brightness such as Alfvén wave reflections, magnetic mirroring of the electrons, the local interaction at Io and kinetic effects close to Jupiter. We identify the effects contributing the most to the modulation of the brightnesses of the three brightest components of the Io footprints: the main and reflected Alfvén wing spots and the transhemispheric electron spot. We show in particular that the modulation of the efficiency of the electron acceleration can be of greater importance than the modulation of the power generated at Io. We reproduce the average modulation of the spot brightnesses and present an extensive discussion of possible explanations for the observed features not reproduced by our model. [less ▲]

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See detailEvolution of the Io footprint morphology
Bonfond, Bertrand ULiege; Grodent, Denis ULiege; Gérard, Jean-Claude ULiege et al

Conference (2008, April)

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See detailEvolution of the Kızılırmak river and its interaction with the North Anatolian Fault, Turkey
Drab, Laureen; Hubert, Aurelia ULiege; Benedetti, Lucilla et al

in AGU Abstract (2010, December)

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See detailEvolution of the Northern Rockweed, Fucus distichus, in a Regime of Glacial Cycling: Implications for Benthic Algal Phylogenetics
Laughinghouse, Haywood, Dail; Müller, Kirsten; Adey, Walter et al

in PLoS ONE (2015), 10(12), 0143795

Northern hemisphere rockweeds (Fucus) are thought to have evolved in the North Pacific and then spread to the North Atlantic following the opening of the Bering Strait. They have dispersed and widely ... [more ▼]

Northern hemisphere rockweeds (Fucus) are thought to have evolved in the North Pacific and then spread to the North Atlantic following the opening of the Bering Strait. They have dispersed and widely speciated in the North Atlantic and its tributary seas. Fucus distichus is likely near the ancestral member of this genus, and studies have shown that there are several species/subspecies in this complex (i.e. F. evanescens and F. gardneri). We used phylogenetic and haplotype analyses to test the phylogenetic relationships and biogeogra- phy of F. distichus. Our data and subsequent analyses demonstrate that, unlike previous studies that lacked samples from an extensive geographical area of the Arctic and Subarc- tic, there is a distinct Arctic haplotype that is the source of subspecies in both the North Pacific and North Atlantic. Fucus distichus occupies a low tide zone habitat, and in Arctic/ Subarctic regions it is adapted to the severe stress of sea ice coverage and disturbance dur- ing many months per year. We hypothesize that the very large geographic area of Arctic and Subarctic rocky shores available to this species during interglacials, supported by large Arctic/Subarctic fringe areas as well as unglaciated refugia during glacial cycles, provided a robust population and gene pool (described by the Thermogeographic Model). This gene pool dilutes that of the more fragmented and area-limited Temperate/Boreal area popula- tions when they are brought together during glacial cycles. We suggest that similar subspe- cies complexes for a variety of Arctic/Subarctic shore biota should be examined further in this context, rather than arbitrarily being split up into numerous species. [less ▲]

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See detailEvolution of the palaeoenvironment of the Medjerda delta (Tunisia) and geoarchaeology of the ancient city of Utica
Pleuger, Elisa ULiege; Abichou, Hakim; Gadhoum, Ahmed et al

Conference (2016, January 27)

Phoenician Utica remains today largely unknown, as is its role in the Phoenician expansion in the western Mediterranean. Aristotle and Pliny the Elder mention Utica as a maritime and port city and ... [more ▼]

Phoenician Utica remains today largely unknown, as is its role in the Phoenician expansion in the western Mediterranean. Aristotle and Pliny the Elder mention Utica as a maritime and port city and estimate its origin around the 11th c. BC. However, in the present state of research, no archaeological evidence is earlier than the 9th c. BC, and the location of the Phoenician and Roman port infrastructures remains unknown. Today, the ancient city is located on a promontory in the heart of the Medjerda delta, 10 km inland. This project proposes an interdisciplinary effort to understand the Medjerda delta landscape changes during the Holocene. It starts from an archaeological problem and proposes the contribution of geoarchaeology to the understanding of the relationship between ancient societies and their environment. The fluvial palaeoenvironments and sedimentary processes are studied through the mechanical extraction of cores (15-20 m deep) to reach the early Holocene. Selected sediment samples are then studied in laboratory, using different and complementary approaches. The location of port infrastructures will bring initial answers to the question of the foundation of the city. The study of river palaeoenvironments of the Medjerda delta during the Holocene aim at a better understanding of the nature of the settlement, as well as the function of the city of Utica over time. This study will also assess the impact of the ancient city on the environment and understand how the city adapted to the mobility of this Mediterranean delta. Furthermore, the analysis of sedimentary processes causing the filling of the harbour basin will lead to speculation about the causes of the abandonment of the structures and more generally the decline of the city in favor of Carthage. It will also examine whether natural or anthropogenic factors have influenced this deltaic progradation over the centuries. [less ▲]

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See detailEvolution of the Peierls distortion in liquid As xSb 1-x compounds
Raty, Jean-Yves ULiege; Gaspard, Jean-Pierre ULiege; Ceolin, R. et al

in Journal of Non-Crystalline Solids (1998), 232-234

The local order in the liquid binary alloy As xSb 1-x (0lesxles1) is studied by short-wavelength (lambda=0.7 Aring) neutron scattering. The coordination number (Z) and the interatomic distances (d) are ... [more ▼]

The local order in the liquid binary alloy As xSb 1-x (0lesxles1) is studied by short-wavelength (lambda=0.7 Aring) neutron scattering. The coordination number (Z) and the interatomic distances (d) are analyzed in terms of the As concentration: Z increases continuously, from a value of 3.5 for pure arsenic to a value of 6.3 for pure antimony, whereas d shows a departure from Vegard's rule. The interatomic distance increases in the range 0.15lesxles1.00 and is almost constant in the range 0.00lesxles0.15. A simple tight-binding model is developed, which indicates that the relevant parameter is the hardness of the core repulsion between the atoms [less ▲]

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See detailEvolution of the Peierls distortion in liquid AsxSb1-x compounds
Raty, Jean-Yves ULiege; Gaspard, Jean-Pierre ULiege; Céolin, R. et al

in Journal of Non-Crystalline Solids (1998), 232-234

The local order in the liquid binary alloy AsxSb1-x (0 ≤ x ≤ 1) is studied by short-wavelength (λ = 0.7 Å) neutron scattering. The coordination number (Z) and the interatomic distances (d) are analyzed in ... [more ▼]

The local order in the liquid binary alloy AsxSb1-x (0 ≤ x ≤ 1) is studied by short-wavelength (λ = 0.7 Å) neutron scattering. The coordination number (Z) and the interatomic distances (d) are analyzed in terms of the As concentration: Z increases continuously, from a value of 3.5 for pure arsenic to a value of 6.3 for pure antimony, whereas d shows a departure from Vegard's rule. The interatomic distance increases in the range 0.15 ≤ x ≤ 1.00 and is almost constant in the range 0.00 ≤ x ≤ 0.15. A simple tight-binding model is developed, which indicates that the relevant parameter is the hardness of the core repulsion between the atoms. © 1998 Elsevier Science B.V. All rights reserved. [less ▲]

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