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Peer Reviewed
See detailÉtude du récit de vie de l’adulte à haut potentiel
Mormont, Elodie; Gauthier, Jean-Marie ULg; Englebert, Jérôme ULg

Poster (2015, January 21)

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See detailL'étude du récit interactif : épistémologie et constitution du corpus
Hurel, Pierre-Yves ULg

Conference (2013, May 16)

Réflexions sur la constitution d'un corpus hétérogène dans l'étude du récit interactif (jeux vidéo, hypertextes, web documentaires, jeux de rôle, etc.)

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See detailEtude du recyclage de l'eau résiduaire dans la flottation des minerais oxydés cuprocobaltifères du gisement de Luiswishi
Shengo Lutandula, Michel ULg

Doctoral thesis (2014)

The present work aims at improving practices in the management of wastewater from flotation of ores in the Katanga province and suggests the recycling considering its advantages on the environment ... [more ▼]

The present work aims at improving practices in the management of wastewater from flotation of ores in the Katanga province and suggests the recycling considering its advantages on the environment safeguarding, the sustainable management of hydric resources and the economy of flotation reagents standpoint. It focuses on the determination of the best process water-recycling rate in flotation of copper - cobalt oxidised ores from the Luiswishi deposit and on the explanation of phenomena implicated in the depression of malachite and heterogenite in the recycled water presence. The studied ores have been sulphidised (NaSH) prior to flotation with KAX using the process water recovered from the industrial effluents and a Lab scale replication of the New Concentrator in Kipushi (NCK) flow sheet to simulate the full-size plant operations. The following methodological approach has been adopted: • The lab flotation tests of the pulps originating from the NCK grinding circuit while varying the proportion of the recycled process water added to the feed water in view to determine the proportion which gives a concentrate grading at least 2% Co at the recovery of 80% and at least 7% Co at the recovery of 60% respectively at the rougher and cleaner stages; • The study of the effects from the recycled water chemical components on flotation of malachite and heterogenite through flotation of the studied ores in the presence of S2O32-, SO42-, HCO3-, Ca2+ and Mg2+ introduced in the feed water (demineralised water) through dissolution of their analytical graded-salts and based on the follow-up of the Cu-Co recovery and the roughing flotation concentrates mineralogical analysis by the polarised light microscopy, the X- rays diffraction and the scanning electron microscopy; • The study of the behaviour of malachite and heterogenite based firstly on electrochemical investigations of the pulp (pH, Eh, Es and DO), the leaching tests and sulphidisation of malachite and heterogenite with NaSH in presence of S2O32-, SO42- and HCO3. Secondly, based on thermodynamical calculations for the establishment of the Pourbaix diagrams of the systems Cu(Co-Cu) – Chemical species – Water at 25 °C and the Drift spectroscopic analysis (4000 à 400 cm-1) of malachite after sulphidisation with NaSH and agitation with KAX in the presence of S2O32-, SO42- and HCO3-. The obtained results have shown that the process water recycling is successful when 20% of the recycled water is added to the feed water since one obtains a concentrate grading 2% Co at the recovery of 80% at the rougher stage. However, considering the significant drops in the grade and the recovery of cobalt in the concentrate observed at the cleaner stage, a proportion of 10% has been suggested as optimal for the overall flotation circuit because 82% cobalt were recovered at rougher stage bringing at the cleaner stage a concentrate grading 9.5% Co at the recovery of 63%. Beyond 10%, the process water recycling has proved detrimental to flotation efficiency owing to the build-up of chemical species (S2O32-, SO42-, HCO3-, Ca2+, Mg2+ and Cl-) in the feed water, which becomes corrosive and scaling leading to depression of malachite and heterogenite. This depression results from an increase in the valuable minerals hydrophilicity boosted-up by their strong dissolution in water in the presence of S2O32-, SO42 and HCO3- leading to alterations in their surface properties and the exaggerated liberation of copper and cobalt ions in solution responsible for the overconsumption of NaSH and KAX. [less ▲]

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See detailEtude du régime alimentaire du sanglier (Sus scrofa L.) dans les Ardennes belges
Palata Kabudi, Jean Claude; Fetter, Serge; Libois, Roland ULg et al

in Cahiers d'Ethologie (1987), 7(3), 223-246

The wild boar's diet is investigated in two forests of the Belgian Ardenne: the Nismes deciduous forest and the Transinne coniferous plantations. Two complementary approach are compared: analysis of ... [more ▼]

The wild boar's diet is investigated in two forests of the Belgian Ardenne: the Nismes deciduous forest and the Transinne coniferous plantations. Two complementary approach are compared: analysis of faeces collected throughout the year and analysis of stomach contents during the hunting season only. The faeces analysis method allows to follow the diet seasonal variations but conceals the occurence of some feed and minimizes the ingestion of vertebrates and of artificial fodder. It results from both approaches that wild boars are opportunist and omnivorous with an obvious tendency to herbivory. The human influence, direct (artificial supply) or indirect (neighbouring cultivated open fields, forest and game management, enclosure, lot of disturbances), plays the leading part in determining wild boar's diet and its food search. As a whole, plant products from natural origin come in second place in its diet whereas other feed always remain occasional, with the exception of acorn and beech mast when superabouding. A few suggestions for reducing wild boar's damage to crop and forests close the paper [less ▲]

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See detailEtude du régime alimentaire et la stratégie trophique saisonnière de la loutre d'Europe (Lutra lutra) sur l'oued Beht (Maroc)
Fareh, Mostafa; Libois, Roland ULg; Gmira, Najib et al

Conference (2012, May)

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See detailÉtude du régime et de la sélectivité alimentaire du grand cormoran (Phalacrocorax carbo) sur le lac Kivu (R.D. Congo)
Musema Bahizire, Altor; Libois, Roland ULg

in Annales des Sciences et Sciences Appliquées de l'Université Officielle de Bukavu (2010), 2

This contribution intends to give a preliminary view of the diet of the Cormorant on the lake Kivu. Fifty pellets were collected from August to October 2004 in a colony situated in Bukavu and analysed. A ... [more ▼]

This contribution intends to give a preliminary view of the diet of the Cormorant on the lake Kivu. Fifty pellets were collected from August to October 2004 in a colony situated in Bukavu and analysed. A reference collection of fish skull bones was also prepared and correlations between the length of some characteristic bones and the total length of the fish were computed, allowing the assessment of the length of each prey identified in the pellets. The cormorants eat mainly Haplochromis species (either in relative abundance or occurrences) but the biomass intake is dominated by the genera Tilapia and Oreochromis (together: 65 %). The importance of catfish (Clarias sp.) or barbels (Barbus sp.) is very small (< 4%, whatever the expression of the results). The sardine Limnothrissa miodon appears in 1 out of 5 pellets but its contribution in terms of biomass is negligible. Comparing the diet with the available resources, it appears that the cormorant is an opportunistic predator, taking almost all the available taxa (except Raiamas moorii) without selecting a particular one, except the big cichlids (genus Tilapia and Oreochromis). However, more than 90% of its preys are small fish measuring less than 10 cm. [less ▲]

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See detailEtude du reservoir genetique de la legumineuse alimentaire Phaseolus lunatus L. par l'analyse electrophoretique d'isozymes.
Maquet, A.; Wathelet, Bernard ULg; Baudoin, Jean-Pierre ULg

in Bulletin des Recherches Agronomiques de Gembloux (1994), 29(3),

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See detailEtude du rôle de Clostridium perfringens dans l'entérotoxémie bovine
Manteca, Christophe; Daube, Georges ULg; Mainil, Jacques ULg

Conference (1999)

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See detailEtude du role de Clostridium perfringens dans l'entérotoxémie bovine
Manteca, Christophe; Daube, Georges ULg; Mainil, Jacques ULg

in Bulletin et Mémoires de l'Académie Royale de Médecine de Belgique (1999), 154(6, Pt 2),

Bovine enterotoxaemia is an acute to peracute syndrome occurring mainly in calves and characterized by the sudden or very rapid death of the calf, with colics, convulsions and nervous disorders as ... [more ▼]

Bovine enterotoxaemia is an acute to peracute syndrome occurring mainly in calves and characterized by the sudden or very rapid death of the calf, with colics, convulsions and nervous disorders as clinical signs, if any. The most pronounced lesion is a necrohaemorrhagic enteritis of the jejunum, the ileum, and sometimes the colon. Suckling beef calves are the most frequently affected ones. In 67% of the 78 field cases investigated, some kind of stress was observed 24 to 36 hours prior to the death: change in diet or pasture, vaccination... The most frequently isolated bacteria, and the one isolated in highest numbers, was non-sporulated non-enterotoxigenic toxinotype A Clostridium perfringens. Reproduction of the lesions was successful in a ligated intestinal loop assay in one calf with a few of these strains, more especially with one of them, which was shown later to produce another recently described toxin, the beta 2 toxin. A role for this beta 2 toxin in bovine enterotoxaemia is thus speculated for future research. [less ▲]

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See detailEtude du rôle de Clostridium perfringens dans l'entérotoxémie du veau et prophylaxie
Daube, Georges ULg; Kaeckenbeeck, A.; Mainil, Jacques ULg et al

Conference (1990)

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See detailEtude du rôle de l’Hypoxia Inductible Facteur 1 dans les cellules myéloïdes lors d'allergie des voies respiratoires
Toussaint, Marie ULg

Doctoral thesis (2012)

Adaptive Th2 immune responses play a major orchestrating role in the development of airway allergy in mammals. It is currently known that the induction of Th2 responses closely depends on the activation ... [more ▼]

Adaptive Th2 immune responses play a major orchestrating role in the development of airway allergy in mammals. It is currently known that the induction of Th2 responses closely depends on the activation of innate immunity. Through its action on innate immune cells, Hypoxia inducible factor 1 (Hif1) has been described as a major regulator of inflammatory responses. Airway allergy is a disease whose incidence is in constant increase in developed countries, and the potential implication of Hif1 in innate immune cells during the development of such disease remains currently unknown. Therefore, we were interested in the involvement of Hif1 within innate immune cells in two experimental models of allergic airway inflammation: allergic asthma and recurrent airway obstruction (RAO). Recurrent airway obstruction is one of the most frequent respiratory syndrome that veterinary equine practice has to deal with in our countries. In the case of RAO, the role of the innate immune system, representing the first line of host defense, has not been investigated so far. We have therefore looked at the potential implication of Hif1 in pulmonary innate immune cells during this disease. We have found that, upon allergenic challenge, Hif1 expression within pulmonary innate immune cells was significantly increased in RAO-affected horses in comparison to the control animals. In addition, Hif1 expression was positively correlated to the severity of clinical dysfunctions in RAO-affected horses. We have also shown that the presence of hay-derived LPS could specifically increase Hif1 expression in macrophages. As previously described in other models of inflammation, these results allowed us to show, in a model of RAO, that Hif1 plays a pro-inflammatory role in innate immune cells. Since 90% of innate immune cells of a healthy horse are macrophages, we decided to further investigate the implication of Hif1 in lung myeloid cells. In the second study, for technical reasons, we decided to focus on another model of airway allergy, namely allergic asthma. Although molecular and cellular mechanisms governing asthma development are well characterized, very few information is available regarding the mechanisms that can prevent the development of this disease in healthy subjects. The identification of such mechanisms could be key to understand the origin of development of that epidemic disease as well as to improve the strategies of prevention. We have found that mice that were specifically deficient in Hif1 within myeloid cells (Hif1αm-/-) developed significantly more allergic inflammation in comparison to control mice. We have further shown that these mice had a higher inclination to develop a Th2 response upon allergenic challenge. We then proved that the increase of antigen-specific Th2 responses in Hif1αm-/- mice was the result of increased lymph node dendritic cells migration and antigen presentation. These results suggested that a brake to DC activation by allergens was lost following deletion of myeloid Hif1. Finally, we have found that the specific deletion of Hif1 in interstitial macrophages was indeed responsible of the observed effects. Indeed, we have shown that the TLR-dependent activation of Myd88 in interstitial macrophages induced increased expression of Hif1, thereby increasing IL-10 production from interstitial macrophages. In addition, following HDM stimulation, we observed that Hif1αm-/- interstitial macrophages produced significantly less IL-10 than control interstitial macrophages. Since we have previously shown that interstitial macrophages were capable of blocking dendritic cell activation through the production of IL-10, we proposed that Hif1 was able to control the immunoregulatory functions of interstitial macrophages by regulating their IL-10 production. Our work revealed a crucial role for Hif1 in interstitial macrophages for maintaining the immune homeostasis in the lung. It also suggests for the first time that Hif1 within innate immune cells can display an anti-inflammatory role. As a conclusion, we have been able to assess the importance of Hif1 activation within innate immune cells in the regulation of airway allergy development. We have further proposed that a compartmentalization of pro- and anti-inflammatory functions of Hif1 exists in immune cells. In opposition to what we obtained in the first study and what is currently known in the literature; we have found an anti-inflammatory role for Hif1 in innate immune cells. Indeed, thanks to its role in interstitial macrophages, Hif1 can play a crucial role in the prevention of aberrant immune responses against harmless antigens by preventing allergic sensitization. Hif1 therefore plays a key role in maintaining lung mucosal immune homeostasis. [less ▲]

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See detailEtude du rôle de l'immunité innée dans le cancer du col de l'utérus associé à une infection par le papilloma virus humain
Willems, Jérôme ULg

Master's dissertation (2009)

De plus en plus d’études mettent en avant l’importance de l’immunité innée, et plus particulièrement celle des lymphocytes innés tel que les cellules NK et les cellules TCR gamma-delta dans les réponses ... [more ▼]

De plus en plus d’études mettent en avant l’importance de l’immunité innée, et plus particulièrement celle des lymphocytes innés tel que les cellules NK et les cellules TCR gamma-delta dans les réponses immunitaires (Guerra et al., 2008; Liu et al., 2008). Le papillomavirus humain (HPV) est reconnu comme étant le principal agent causatif du cancer du col de l’utérus et de ses lésions précurseurs (SIL : Squamous intraepithelial lesions) (Walboomers et al., 1999). Le système immunitaire joue un rôle important dans le développement de ce type de cancer. Ceci a été démontré par une plus grande incidence des lésions cervicales chez les patients immunodéprimés lors d’une infection par HIV (virus d’immunodéficience humaine) (Ellerbrock et al., 2000) ainsi que la mise en évidence d’anomalies immunitaires dans la TZ (zone de transformation) et dans les SIL (Squamous Intraepithelial Lesion) (Giannini et al., 1998; Jacobs et al., 2003). Nous avons d’abord voulu déterminer les différentes sous-populations de cellules NK et TCR gamma-delta au sein des SIL au moyen de nouveaux marqueurs permettant une meilleure caractérisation celles-ci. Dans la seconde partie, nous nous sommes intéressés à l’interaction des cellules NK avec le virus HPV. Nous voulions déterminer si celui-ci induisait une prolifération de cellules NK. Nous avons donc mis au point le test de prolifération au CFSE sur un petit nombre de cellules et utilisé des VLP d’HPV16, car cette souche d’HPV se retrouve dans plus de 50% des cancers du col de l’utérus. Nous nous sommes ensuite intéressés à l’expression de MICA (MHC class I-related chains A), connu pour être un ligand du récepteur activateur NKG2D des cellules NK (Pende et al., 2001), sur les lignées CaSki et SiHa (HPV positives) par rapport à la lignée C33a (HPV négative). Nous avons également étudié l’effet du TGFb-1 (Tumor Growth Factor beta 1) sur l’expression de MICA de ces lignées car celui-ci est présent dans la TZ et il a été démontré au laboratoire qu’il augmentait l’expression de MICA sur les cellules CaSki. Trop peu d’expériences ont été réalisées sur les populations lymphocytaires des lésions et l’effet prolifératif des VLP d’HPV sur les cellules NK pour tirer des conclusions. Toutefois les techniques sont maintenant bien mises au point pour réaliser d’autres expériences. Les résultats ont confirmé ceux obtenus précédemment par le laboratoire d’accueil pour l’expression de MICA à la surface des lignées cellulaires mais pas pour les effets du TGFb-1 sur les cellules CaSki. Nous avons toutefois mis en avant une diminution de prolifération et l’induction de changements morphologiques dus au TGFb-1 sur les lignées HPV positives [less ▲]

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See detailEtude du rôle des bactéries symbiotiques de pucerons dans l'adaptation aux plantes hôtes
Yattara, Almouner Ag Alhamis ULg

Master of advanced studies dissertation (2007)

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