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See detailInfluence qualitative et quantitative du mode de séchage sur l'huile essentielle de Thymus fontanesii de l'Algérie
Sidali, Lamia; Brada, Moussa; Fauconnier, Marie-Laure ULiege et al

Poster (2017, May)

Cette étude a pour but d`étudier l`influence du mode de séchage (à l’ombre et au soleil) sur le rendement et la composition chimique de l`huile essentielle de Thymus fontanesii de l`Algérie obtenue par ... [more ▼]

Cette étude a pour but d`étudier l`influence du mode de séchage (à l’ombre et au soleil) sur le rendement et la composition chimique de l`huile essentielle de Thymus fontanesii de l`Algérie obtenue par extraction assistée par induction électromagnétique. Les résultats ont montré que le séchage à l`ombre a donné un meilleur rendement de (1.12%) après une période de séchage de 10 jours jusqu`à la stabilisation de teneur en eau, alors que le séchage au soleil pendant 8 jours donne un rendement de (0.89%). La composition chimique de l`huile essentielle de Thymus fontanesii (TF) a été analysé par la chromatographie en phase gazeuse couplée à la spectrométrie de masse (GC/MS) et la chromatographie en phase gazeuse a ionisation de flamme (GC/FID). [less ▲]

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See detailInfluence sur le tissu tendino(-musculaire) du mode de contraction en entraînement : modèle animal
Kaux, Jean-François ULiege; Drion, Pierre ULiege; Croisier, Jean-Louis ULiege et al

in Julia, Marc; Hirt, Daniel; Croisier, Jean-Louis (Eds.) et al Tendon et jonction tendino-musculaire - De la biomécanique aux applications thérapeutiques (2011)

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See detailInfluence, information and item response theory in discrete data analysis
Magis, David ULiege

Doctoral thesis (2007)

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See detailInfluencer sans contraindre: le cas du décret-mémoire
Nossent, Jérôme ULiege

Article for general public (2015)

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See detailInfluences de l'environnement d'un parc éolien sur la prévision de sa production électrique à l'aide des modèles GFS (50km/3h) et WRF (2km/15min) : Le cas du parc éolien d'Amel (Haute-Belgique)
Doutreloup, Sébastien ULiege; Fettweis, Xavier ULiege; Erpicum, Michel ULiege

in Fazzini, Massimiliano; Beltrando, Gérard (Eds.) Actes du XXIVème Colloque International AIC : Climat Montagnard et Risques (2011, September 06)

The economic and climate contexts require to use more electricity from wind farms. However this kind of production is intermittent, therefore it is necessary to forecast this resource at least 1 day ahead ... [more ▼]

The economic and climate contexts require to use more electricity from wind farms. However this kind of production is intermittent, therefore it is necessary to forecast this resource at least 1 day ahead. Our laboratory has developed a forecasting model of wind-based electricity generation based on a global meteorological model (GFS) with a resolution of 50 km and 3 h. But this model has a resolution too coarse for a wind farm. So we have configured the regional model WRF with resolution of 2 km and 15 min to obtain better forecasts. Finally, the WRF model provides better forecasts, but both must be adjusted to take into account the direct environment of the wind farm. [less ▲]

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See detailInfluences de l'environnement sur la fonction endocrinienne
Charlier, Corinne ULiege

Conference (2009)

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See detailInfluences de Parthénios de Nicée sur les Héroïdes et les Métamorphoses d'Ovide
Vandersmissen, Marc ULiege

Master's dissertation (2010)

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See detailInfluences de variables temporelles (time-blind, time gap) sur l'évaluation quantitative de la psychopathologie
Mormont, Christian ULiege; Von Frenckell, R.; Lottin, Thierry ULiege et al

in L'Encéphale (1984), 10(1), 3-7

Investigated the influence of methodological conditions (i.e., time-blind evaluation, chronological vs random order, and suppression of the time gap between evaluations) on the objectivity and sensibility ... [more ▼]

Investigated the influence of methodological conditions (i.e., time-blind evaluation, chronological vs random order, and suppression of the time gap between evaluations) on the objectivity and sensibility of quantitative evaluation of psychopathology. Different evaluations of videotaped interviews did not demonstrate systematic effects of these temporal conditions. It is suggested that other variables (monotony, order of sequences, verbal inertia, contingencies) may play a greater role. Within the methodological limits of the present study, the time-blind evaluation was the most sensitive [less ▲]

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See detailInfluences des différences sexuées en matière de temporalités et de normes démographiques sur les accrières professionnelles
Gavray, Claire ULiege

Scientific conference (2010, December 07)

au bout du compte, l'offre d'emploi faite aux femmes et les débuts de trajectoires professionnelle auxquelles elles ont accès jouent plus sur leurs carrières que les facteurs familiaux. Si les femmes peu ... [more ▼]

au bout du compte, l'offre d'emploi faite aux femmes et les débuts de trajectoires professionnelle auxquelles elles ont accès jouent plus sur leurs carrières que les facteurs familiaux. Si les femmes peu diplômées restent aujourd'hui particulièrement exposées au non emploi (sans comparaison avec ce qui se passe pour les hommes dans ce cas), l'ensemble des femmes connait un risque élevé de commencer leur trajectoire professionnelle dans des emplois atypiques et de s'y enliser (significativement beaucoup plus que les hommes).... [less ▲]

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See detailInfluences of blubber composition and profile in the assessment of POPs levels in free-ranging cetaceans
Pinzone, Marianna ULiege; Budzinski, Hélène; Tasciotti, Aurelie et al

Poster (2015, February 28)

Investigating the food and feeding ecology of free-ranging cetaceans has always been very challenging. Still now, mass stranding events represent almost the only opportunity to collect valid information ... [more ▼]

Investigating the food and feeding ecology of free-ranging cetaceans has always been very challenging. Still now, mass stranding events represent almost the only opportunity to collect valid information on these large and elusive animals. Biopsy darting is a non-lethal tissue sampling technique which permits the collection of tissues from living and healthy individuals. However, important discussions exist about how efficient this method is in chemical analyses where the percentage lipid content of the tissue is of great importance. Biopsies of skin and blubber were conducted on 49 long-finned pilot whales (Globicephala melas), 61 sperm whales (Physeter macrocephalus) and 70 fin whales (Balaenoptera physalus) in the North Western Mediterranean Sea (NWMS) from 2006 to 2013. Lipid content, δ13C, δ15N values and ΣPCBs were analysed and compared with previous studies conducted on stranded and biopsied individuals. Lipids extraction was operated via ASE; δ13C, δ15N values and POPs levels were assessed through IR-MS and GC-MS respectively. δ15N values were 12.2±1.3‰ for sperm whales, 10.5±0.7‰ for pilot whales and 7.7±0.8‰ in fin whales, positioning sperm whales at higher trophic levels. δ13C instead was similar and amounted to −17.3±0.4‰, −17.8±0.3‰ and −18.7±0.4‰ respectively. Pilot whales presented the highest concentrations of ΣPCBs (38666 ± 25731ng.g-1 lw) followed by sperm whales (22849 ± 15566ng.g-1 lw) and fin whales (5721±5180ng.g-1 lw). Lipids percentage differed significantly between species. Sperm whales showed the lowest lipid content with an average of 12±9%, whereas for long-finned pilot whales it was 22±21% and for fin whales 31±14%. Lipid content of the two odontocetes varied between years of sampling, whilst for fin whales remained similar. The PCBs concentrations, especially in sperm whales, were in discordance with previous studies conducted in the same area and our δ13C, δ15N values. We hypothesized that (1) the extreme low lipid content found in the blubber, (2) the extraction procedure and (3) the biopsies technique, could explain such different pattern. Several papers demonstrated how POPs concentrations in cetaceans blubber are strongly influenced by its thickness, stratification and lipid profile. Therefore, the particular characteristics of blubber composition of deep—diving income breeders such as sperm whales, may not allow an efficient representation of POPs concentrations through the use of biopsies. [less ▲]

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See detailInfluences of electric charges on an isolated drop
Brandenbourger, Martin ULiege

Doctoral thesis (2016)

Research such as the famous Millikan experiment or the studies concerning thunderclouds have shown that droplets can be considerably influenced by an excess of electric charges. Indeed, an excess of ... [more ▼]

Research such as the famous Millikan experiment or the studies concerning thunderclouds have shown that droplets can be considerably influenced by an excess of electric charges. Indeed, an excess of charges can affect the intrinsic properties of a droplet, such as its natural oscillation frequency or its internal pressure. Moreover, the electric charges in excess in droplets can also interact with external electric fields. In this thesis, we investigated the influence of electric charges on millimetric droplets that are electrically isolated. In literature, research on isolated charged droplets are mainly focused on droplets with a micrometric size. The lack of studies concerning millimetric charged droplets is explained by the difficulty storing them while avoiding charge leakage. In order to answer to this issue, we examined three storage systems limiting the charge leakage: the microgravity, the vibrating bath method and the Leidenfrost effect. Through these systems, we studied the influence of electric charges on the droplet physical properties, but also the interaction between the charged droplet and its storage system. Furthermore, we investigated the interaction of charged droplets with external electric fields. More precisely, we studied the interaction between two electrically charged droplets and the interaction between one charged droplet and an external homogeneous electric field. A first set of experiments on electrically charged droplets allowed us modeling the charge migration process in liquids and the charge leakage from a millimetric droplet. In particular, we identified and modeled a new mechanism of charges leakage occurring at a time scale of several minutes. Moreover, we confirmed the influence of the electric charges on the droplet surface energy previously deduced from experiments on micrometric droplets. Concerning the three storage systems, the experiments performed in microgravity allowed us describing the influence of the electric interaction on the impact between two charged droplets. The diverse behaviors observed were compared to the cases of impacts between two neutral drops. On a different note, the study of a charged droplet moving on the surface of a vibrating bath because of the influence of an external electric field gave new insights on the interaction between a bouncing droplet and a viscous liquid bath. For example, we observed a ``go-stop" motion during which the droplet horizontally moves when it bounces away and is stopped during its interaction with the liquid bath. We showed that this motion occurs when large droplets are influenced by a weak electric field. Droplets with this kind of motion move with a constant average speed, which makes them easily manoeuvrable. Therefore, the control of the droplet motion led to the development of a new microfluidic prototype. Via this new setup, basic microfluidic tasks can be performed without polluting droplet via contacts with solids or liquids. With these results in mind, we also examined the interaction between two charged droplets bouncing on the vibrating bath. This study brought new insights on the interaction between two charged droplets. Indeed, we observed that two drops with the same charges tend to remain at an equilibrium distance. Our study showed that this equilibrium distance is due to the compensation of the electric repulsion by capillary attraction at the surface of the vibrating bath. Finally, our study of charged droplet in Leidenfrost state on a liquid bath led to a better understanding of the interaction between charged liquid interfaces. Indeed, we showed that electric charges cause the early coalescence of charged droplet because of an increase in the vapor layer drainage. We conclude from our results that an excess of electric charges influences ostensibly the intrinsic behavior of a droplet and its interaction with the environment. Furthermore, each storage system studied brought answers to specific issues. The study of the impact between charged droplets in microgravity outlines new explanations on the behavior of thunderclouds. The results accumulated on the micromanipulation of charged droplet bouncing on a vibrating bath opens the way to a new kind of microfluidic system. Finally, the study on the charged Leidenfrost droplets describes new ways to investigate the influence of electric charges on liquid interfaces. [less ▲]

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See detailInfluences of feeding behaviour and forage quality on diurnal methane emission dynamics of grazing cows
Blaise, Yannick ULiege; Andriamandroso, Andriamasinoro ULiege; Heinesch, Bernard ULiege et al

in Berckmans, Daniel; Keita, Keita (Eds.) Precision Livestock Farming ‘17 (2017, September 12)

This study aimed to evaluate diurnal methane (CH4) emission dynamics of grazing cattle and highlight their relationships with biotic factors such as the feeding behaviour as well as seasonal changes in ... [more ▼]

This study aimed to evaluate diurnal methane (CH4) emission dynamics of grazing cattle and highlight their relationships with biotic factors such as the feeding behaviour as well as seasonal changes in pasture characteristics. Existing methods to assess grazing ruminants’ daily CH4 emissions provide useful insights to investigate mitigation strategies relying on feeding and genetic selection. Nonetheless such methods based on tracer gases (SF6) or feeding bins equipped with sniffers (e.g. GreenFeed) can hardly cover diurnal CH4 emission fluctuations which can influence the accuracy of total CH4 production estimations. Previous studies in barns showed that emission dynamics strongly vary during post feeding time, leading to a possible bias in estimates of daily CH4 emissions as high as 100%. To investigate whether such fluctuations are also taking place on pasture, a portable device was designed with infrared CH4 and CO2 sensors measuring concentrations in the exhaled air at a high sampling rate (4 Hz). Six grazing dry red-pied cows were equipped with the device and motion sensors during runs of 24h to monitor CH4 and CO2 emissions and detect their feeding behaviours (grazing, rumination and other behaviours), respectively. This experiment was performed in summer and fall in order to cover seasonal changes in pasture forage quality. Methane emission was estimated from the CH4:CO2 concentration ratio and the metabolic CO2 production of the cows. As for barn studies, variations were observed in total daily CH4 emission due to the seasons and diurnal variations were also observed due to animal behaviours. Relationships between animal feeding behaviour and CH4 emissions patterns on pasture were also unravelled. [less ▲]

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See detailInfluences of geothermal sulfur bacteria on a tropical coastal food web
Pascal, P. Y.; Dubois, S. F.; Goffette, A. et al

in Marine Ecology. Progress Series (2017), 578

ABSTRACT: The activity of the geothermal plant at Bouillante in Guadeloupe (French West Indies) releases thioautotrophic bacteria into the coastal environment. Fish counts reveal that fish abundance ... [more ▼]

ABSTRACT: The activity of the geothermal plant at Bouillante in Guadeloupe (French West Indies) releases thioautotrophic bacteria into the coastal environment. Fish counts reveal that fish abundance increases with higher availability of this bacterial resource. In order to evaluate the trophic role of these bacteria, isotopic compositions (C, N, S) of potential consumers were evaluated on transects at increasing distance from the source of bacteria. The 3 mobile fish species examined (<i>Abudefduf saxatilis</i>, <i>Acanthurus bahianus</i>, and <i>Stegastes partitus</i>) ingested and assimilated chemosynthetic bacteria. Similarly, the isotopic composition of the mobile sea urchin <i>Diadema antillarum</i> was different close to the discharge channel, suggesting a diet mainly composed of sulfur bacteria. In contrast, endofauna sampled from the nematode community did not show a diet influence by chemosynthetic bacteria. A broad variety of epifaunal organisms with passive and active suspension-feeding activities were also investigated, including sponges (<i>Aplysina fistularis</i> and <i>Iotrochota birotulata</i>), barnacles (<i>Balanus</i> sp.), bivalve molluscs (<i>Spondylus tenuis</i>) and cnidarians (<i>Pseudopterogorgia</i> sp.), but no strong evidence for sulfur bacteria contributions were determined in the diets of any of these organisms. This was also true for the omnivorous predator annelid <i>Hermodice carunculata</i>. In this coastal oligotrophic environment, only certain opportunistic species seem to benefit from the emergence of a new food item such as chemosynthetic bacteria. [less ▲]

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See detailInfluences of proline and cysteine residues on fragment yield in matrix-assisted laser desorption/ionization in-source decay mass spectrometry
Asakawa, Daiki; Smargiasso, Nicolas ULiege; Quinton, Loïc ULiege et al

in Journal of the American Society for Mass Spectrometry (2014)

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See detailInfluences of the aqueous synthesis way and organosilane nature on the physico-chemical properties of porous alumina
Claude, Vincent ULiege; Vilaseca, Miriam; Tatton, Andrew ULiege et al

in European Journal of Inorganic Chemistry (2016), 2016(11), 1678-1689

The aqueous sol-gel synthesis of γ-Al2O3 modified with different silicon precursors {trimethoxysilane, triethoxysilane and N-[3-(trimethoxysilyl)propyl]ethylene diamine} has been investigated. Two ... [more ▼]

The aqueous sol-gel synthesis of γ-Al2O3 modified with different silicon precursors {trimethoxysilane, triethoxysilane and N-[3-(trimethoxysilyl)propyl]ethylene diamine} has been investigated. Two parameters have been studied: the silicon addition step and the type of silicon alkoxide. A first observation was that adding a silicon alkoxide either before or just after the precipitation step influences both the crystallinity and structure, whereas adding the alkoxide after a long agitation time only slightly modifies the support properties. It was also highlighted that due to their higher reactivity, silicon precursors with methoxy groups interact more strongly with the bulk alumina than the silicon precursors with ethoxy groups. This difference of Si location in the alumina structure permitted not only their resistance toward phase transition to be increased at high temperature, but also to stabilize them more efficiently against sintering under normal and steam conditions. Among the different silicon alkoxides tested, samples prepared with N-[3-(trimethoxysilyl)propyl]ethylene diamine showed very unusual properties. The alumina supports modified with this precursor showed grain-shaped nanocrystallites, whereas all other samples were platelet-like. As a result, this sample presented a very narrow pore diameter distribution of around 5 nm and a remarkably high specific surface area (530 m2/g). [less ▲]

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