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See detailProduction et utilisation du colza en Belgique.
Cartrysse, C.; Cors, F.; Wathelet, Jean-Paul ULg

in GCIRC Bulletin (1991)

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See detailProduction laitière et nombre de traites de vaches laitières en prairie avec un robot: effets des facteurs environnementaux.
Dufrasne, Isabelle ULg; Robaye, Vincent ULg; Knapp, Emilie ULg et al

Poster (2012)

En Belgique, comme dans d'autres pays européens, le recours à la traite robotisée est en augmentation. La majorité des troupeaux traits avec un robot ne pratique pas le pâturage car les exploitants ... [more ▼]

En Belgique, comme dans d'autres pays européens, le recours à la traite robotisée est en augmentation. La majorité des troupeaux traits avec un robot ne pratique pas le pâturage car les exploitants considèrent que cette méthode n'est pas conciliable avec le pâturage. La fragmentation des parcelles est aussi un frein au pâturage. La mise en place d'un robot dans une structure mobile permet d'utiliser le même robot à l'étable en hiver et dans les prairies distantes de l'exploitation en été. L'objectif de cette étude est de tester l'effet de facteurs environnementaux, l'animal, la complémentation, la distance entre le robot et la parcelle, les numéros du jour dans la parcelle et de cycle de rotation sur la production laitière (PL) et le nombre de traites (NT). [less ▲]

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See detailProduction laitière et santé mammaire (Bio Ingénieurs)
Hanzen, Christian ULg

Learning material (2013)

Ce cours de 4 heures s'inscrit dans cadre du module "Production laitière par le ruminant" dispensé aux étudiants de master bio-ingénieur en sciences agronomiques. Les objectifs spécifiques ont été définis ... [more ▼]

Ce cours de 4 heures s'inscrit dans cadre du module "Production laitière par le ruminant" dispensé aux étudiants de master bio-ingénieur en sciences agronomiques. Les objectifs spécifiques ont été définis en accord avec le professeur Yves Beckers co-responsable du module. Ce cours a pour objectif général de définir la mammite, ses conséquences, ses signes d'alerte au niveau de l'individu et du troupeau, son approche diagnostique, ses facteurs de risque au niveau individuel et d'élevage et ses grandes lignes d'approche thérapeutique. [less ▲]

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See detailProduction lamellaire aurignacienne à Mitoc-Malu Galben, Roumanie
Noiret, Pierre ULg; Zwyns, Nicolas; Chirica, Vasile

Conference (2006, September)

Although retouched bladelets (Dufour or others) were not recovered, the Aurignacian assemblages from Mitoc-Malu Galben (Romania) probably belongs to the Krems-Dufour type Aurignacian. In the lithic ... [more ▼]

Although retouched bladelets (Dufour or others) were not recovered, the Aurignacian assemblages from Mitoc-Malu Galben (Romania) probably belongs to the Krems-Dufour type Aurignacian. In the lithic material gathered by V. chirica in the 1980s, evidence indicates the existence of bladelet production from carinated tools/cores. A small unpublished lithic assemblage from the 1990s excavations, associated with a hearth, confirms this hypothesis. The operational schemes are described and compared to those from the western and eastern Aurignacian geographic regions. [less ▲]

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See detailProduction ligneuse de la forêt wallonne, l'apport de l'inventaire permanent régional
Rondeux, Jacques ULg; Hebert, Jacques ULg; Bourland, Nils ULg et al

in Forêt Wallonne (2005), (79), 3-18

En Région wallonne, l’inventaire permanent des ressources forestières, mis en place en 1994, permet aujourd’hui de fournir des chiffres d’accroissement basés sur une méthodologie rigoureuse. Les chiffres ... [more ▼]

En Région wallonne, l’inventaire permanent des ressources forestières, mis en place en 1994, permet aujourd’hui de fournir des chiffres d’accroissement basés sur une méthodologie rigoureuse. Les chiffres donnés dans cet article permettent de mieux appréhender la capacité actuelle de production de nos forêts en se basant sur une approche scientifique et non sur des hypothèses. Les principaux résultats sont issus de mesurages réalisés entre novembre 1999 et 2001 et concernent une période d’accroissement de 5 ans. Ces mesures ont permis de se faire une idée de la production moyenne en volume de nos principales essences dont les grandes tendances sont les suivantes : • la production annuelle en volume de l’ensemble de la forêt wallonne productive est estimée à 10,1 m3/ha/an (dont 53 % de cette valeur est à charge de la forêt privée) ; • la production en volume des résineux est de 16,4 m3/ha/an et celle des feuillus s’élève à 5,4 m3/ha/an ; • les prélèvements correspondent à 65 % de la production en feuillu et à 109 % de celle des résineux, dans l’état actuel des surfaces occupées par classe d’âge ou stade de développement des peuplements. [less ▲]

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See detailProduction line real time near infrared (NIR) monitoring
Mantanus, Jérôme ULg; Ziemons, Eric ULg; Streel, Bruno et al

Conference (2009, September)

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See detailLa production littéraire des Belges francophones durant l’entre-deux-guerres. Examen d’un premier inventaire
Dozo, Björn-Olav ULg

in Mémoires du Livre = Studies in Book Culture (2010), 1(2),

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See detailProduction locale des antisérums de groupe sanguin ABO
Bamoleke Sefu, Anaclet; Tshiband-a-Tshish, Alphonse; Munlemvo Mavanga, Nana ULg et al

in Immuno-Analyse & Biologie Spécialisée [=IBS] (2012), 27

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See detailProduction of L-[18F]fluoroamino acids for protein synthesis: overview and recent developments in nucleophilic synthesis
Lemaire, Christian ULg

in PET studies on Amino Acid Metabolism and Protein Synthesis (1993)

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See detailProduction of 3-hydroxy-γ-decalactone, the precursor of two decenolides with flavouring properties, by the yeast Yarrowia lipolytica
Escamilla Garcia, E.; Aguedo, Mario ULg; Gomes, N. et al

in Journal of Molecular Catalysis B : Enzymatic (2009), 57(1-4), 22-26

3-Hydroxy-γ-decalactone is the precursor of dec-2 and dec-3-en-4-olides which are valuable aroma compounds not yet produced. To promote the accumulation of this lactone, the yeast Yarrowia lipolytica was ... [more ▼]

3-Hydroxy-γ-decalactone is the precursor of dec-2 and dec-3-en-4-olides which are valuable aroma compounds not yet produced. To promote the accumulation of this lactone, the yeast Yarrowia lipolytica was placed in different environmental conditions aiming at altering β-oxidation fluxes. The concentration of substrate, pH, aeration and dissolved oxygen level were modified. We observed an important accumulation at low aeration (0.40 molar yields) and, to a lesser extent, at lower pH (0.15). As oxygen played a key-role, we evaluated its effect at fixed dissolved oxygen and at the pH which was the most favourable to the biotransformation (pH 4.5). At 5% and 30% dissolved oxygen, yields reached 0.50. β-Oxidation fluxes are very dependent on the presence of oxygen and conditions of accumulation of 3-hydroxy-γ-decalactone with very high yields were identified. These results are an important step in the production of the two decenolides. Moreover, they show the high dependence of β-oxidation fluxes on environmental conditions and relate these conditions to the accumulation of intermediates, results that are of interest to all the processes using yeast on lipids or alkanes. © 2008 Elsevier B.V. All rights reserved. [less ▲]

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See detailProduction of 4-hydroxydecanoic acid, a g-decalactone precursor, by the psychrophilic yeast Rhodotorula aurantiaca A16.
Belot, J. L.; Lognay, Georges ULg; Marlier, M. et al

Poster (1997, August)

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See detailProduction of a high percentage of male offspring with a natural androgen, 11 beta-hydroxyandrostenedione (11 beta OHA4), in Florida red tilapia
Desprez, D.; Geraz, E.; Hoarea, M. C. et al

in Aquaculture (2003), 216(1-4), 55-65

This paper reports the effects of a natural androgen, 11beta-hydroxyandrostenedione (11betaOHA4), on sex-reversed fry of the Florida red tilapia. In a first approach, the optimal dosage and duration were ... [more ▼]

This paper reports the effects of a natural androgen, 11beta-hydroxyandrostenedione (11betaOHA4), on sex-reversed fry of the Florida red tilapia. In a first approach, the optimal dosage and duration were determined in the laboratory. The sex-reversal treatment was applied on post-yolksac stage fry (10 days after fertilisation at 27degreesC. Dosages of 20, 30, 40 and 50 mg of 11betaOHA4 kg(-1) of food were used during periods ranging from 10 to 35 days. Dosages of 40 or 50 mg of 11betaOHA4 kg(-1) of food during 21-35 days significantly increased the male percentage in sex-reversed groups in comparison to control groups. A lower but still significant deviation of the male percentage was observed when a dosage of 40 mg kg-1 was given during at least 28 days. Lower dosages did not significantly affect the sex ratio of treated groups. Based on the results of these observations, a follow-up study was conducted to evaluate the efficiency of this natural androgen for an intensive production of sex-reversed fry. Optimal dosage (50 mg kg-1) and treatment duration (28 days) were applied to increasing stocking density of fry (8000-11,000 fish m(-2)), producing a mean male percentage of 99.1% on the 510,000 treated fry. This study demonstrates the masculinizing efficiency of 11betaOHA4 in Florida red tilapia. Interest of a natural androgen, used in sex-reversal treatment, is discussed, particularly for the Florida red tilapia strain. (C) 2003 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailProduction of active oxygen species by isolated human chondrocytes.
Henrotin, Yves ULg; Deby-Dupont, G.; DEBY, C. et al

in British Journal of Rheumatology (1993), 32(7), 562-7

The ability of isolated human chondrocytes to produce active oxygen species has been investigated. The two methods for determining H2O2 and hydroxyl radicals (.OH) production were, by a fluorimetric ... [more ▼]

The ability of isolated human chondrocytes to produce active oxygen species has been investigated. The two methods for determining H2O2 and hydroxyl radicals (.OH) production were, by a fluorimetric method (production of dichlorofluorescein from a precursor in the presence of horseradish peroxidase and H2O2) and by a chromatographic method (measurement of ethylene production from gamma-methiol-keto-butyric acid after .OH attack). Chondrocytes were tested, both with and without activation by phorbol myristate acetate (PMA: 10(-6) M), in the presence of Ca2+ (1 x 10(-4) M) and Mg2+ (2 x 10(-4) M) or after variable periods of anoxia under nitrogen (4 to 12 h) followed by reoxygenation (with 95% O2, 5% CO2). Under these experimental conditions, the PMA-excited chondrocytes produced from 80 to 180 nmol of hydrogen peroxide per 1 x 10(6) cells and chondrocytes subjected to anoxia-reoxygenation produced up to 1700 nmol H2O2 per 1 x 10(6) cells. The hydroxyl radical production by PMA or anoxia-reoxygenation excited cells reached 600% of the production of non-excited cells and 1300% when they were subjected to successive stimulations by PMA and anoxia-reoxygenation. The possible pathological significance of these observations is discussed. The results indicate that stimulated human chondrocytes are capable of producing active oxygen species which could play a major role in joint inflammation and cartilage damage. [less ▲]

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See detailProduction of adsorbent materials from dried residual sludges
Fostroy, Philippe; Salmon, Thierry ULg; Crine, Michel ULg et al

Poster (2008, September)

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See detailProduction of alarm pheromone by developing aphids varies in response to their social environment
Verheggen, François ULg; Haubruge, Eric ULg; Demoraes, Consuelo et al

Poster (2008)

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to ... [more ▼]

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to cease feeding, drop from their host plant, and disperse. Because aphid alarm pheromone confers apparent fitness benefits on recipients while its production and release likely entail costs for the emitting aphid, it could be adaptive for aphids to regulate their Eβf production in response to variation in the social environment. To explore this possibility we compared the production of Eβf by Acyrthosiphon pisum (Harris) individuals reared from first-instar larvae to the adult stage in isolation to that of individuals reared among conspecifics or among individuals of a different aphid species, Myzus persicae (Sulzer). Levels of EβF produced in each treatment were assayed by GC-FID quantification of EβF in volatiles collected from crushed aphids. Production of EβF by A. pisum reared in isolation (14.4ng/aphid) was significantly lower than that of aphids reared in a colony of conspecifics (49.1ng/aphid), reared in a M. persicae colony (31.5ng/aphid) or reared among conspecifics of another aaphid clone (52.7ng/aphid). Though A. pisum individuals in our experiments produced less EβF when reared among M. persicae than among conspecifics, this difference was not statistically significant. In a separate experiment we reared A. pisum individuals in isolation and exposed them to the odor of conspecifics. Under these conditions, EβF production was similar to that of aphids reared among conspecifics, suggesting that aphids use volatile cues to assess their social environment and regulate their production of alarm pheromone accordingly. [less ▲]

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See detailProduction of alarm pheromone by developing aphids varies in response to their social environment
Verheggen, François ULg; Mescher, Mark; Haubruge, Eric ULg et al

Conference (2008)

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to ... [more ▼]

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to cease feeding, drop from their host plant, and disperse. Because aphid alarm pheromone confers apparent fitness benefits on recipients while its production and release likely entail costs for the emitting aphid, it could be adaptive for aphids to regulate their Eβf production in response to variation in the social environment. To explore this possibility we compared the production of Eβf by Acyrthosiphon pisum (Harris) individuals reared from first-instar larvae to the adult stage in isolation to that of individuals reared among conspecifics or among individuals of a different aphid species, Myzus persicae (Sulzer). Levels of EβF produced in each treatment were assayed by GC-FID quantification of EβF in volatiles collected from crushed aphids. Production of EβF by A. pisum reared in isolation (14.4ng/aphid) was significantly lower than that of aphids reared in a colony of conspecifics (49.1ng/aphid), reared in a M. persicae colony (31.5ng/aphid) or reared among conspecifics of another aaphid clone (52.7ng/aphid). Though A. pisum individuals in our experiments produced less EβF when reared among M. persicae than among conspecifics, this difference was not statistically significant. In a separate experiment we reared A. pisum individuals in isolation and exposed them to the odor of conspecifics. Under these conditions, EβF production was similar to that of aphids reared among conspecifics, suggesting that aphids use volatile cues to assess their social environment and regulate their production of alarm pheromone accordingly. [less ▲]

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See detailProduction of alarm pheromone in aphids and perception by ants and natural enemies
Verheggen, François ULg

Doctoral thesis (2008)

Most Aphidinae species produce and use (E)-ß-farnesene (Eßf) as an alarm pheromone. This sesquiterpene is released by individuals under attack by a predator, and nearby aphids exhibit a variety of alarm ... [more ▼]

Most Aphidinae species produce and use (E)-ß-farnesene (Eßf) as an alarm pheromone. This sesquiterpene is released by individuals under attack by a predator, and nearby aphids exhibit a variety of alarm behaviours. This PhD thesis aims to better understand how aphids manage their production and emission of alarm pheromone (Chapter IV). We also wanted, in a second step, to improve our knowledge on the roles that Eßf could play in the relationships that aphids have with their predators (Chapter V) and tending ants (Chapter VI), in order to better pinpoint the problem in this very tough context. The aphid predators have indeed a real advantage to be able to use the odorant cues emitted by their prey, to locate them and to select an adequate oviposition site. Ants establish with certain aphid species mutualistic relationships, which occurrence could be facilitated by the use of aphids’ odours. In Chapter IV, we have highlighted that aphid colonies non subjected to attack by predators release constantly small quantities of Eßf in their headspace, which means that this molecule could have additional roles than just acting as an alarm pheromone. In a second study, we demonstrated that the release of Eßf was not contagious, and therefore that a non stressed aphid receiving the alarm signal does not release additional Eßf. Since the production of alarm pheromone is likely to entail physiological cost, we tested and validated the hypothesis that aphids regulate their Eßf production according to their social environment. In Chapter V, we studied the ability of the hoverfly predator Episyrphus balteatus (Diptera, Syrphidae) to be used as biological control agent against aphids infesting tomato plants (Lycopersicon esculentum). After identifying the odours emitted by aphid infested plants, we have demonstrated that although this Diptera is able to perceive all the odours released by the system, it mainly uses Eßf to select its oviposition site. However, the E. balteatus larvae are not adapted to the architecture of tomato plants. We also showed that the Asian ladybeetle Harmonia axyridis (Coleoptera, Coccinellidae) olfaction was adapted to the perception of Eßf and that this beetle is also attracted by this sesquiterpene. Finally, in Chapter VI, we characterized the benefits accruing to aphid populations that have established mutualistic relationships with Lasius niger (Hymenoptera, Formicidae), and have demonstrated the role of Eßf and honeydew, respectively in locating aphid colonies and in the persistence of the mutualism. [less ▲]

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See detailProduction of anionic extracellular polysaccharide by Enterobacter A47 using cheese whey as feedstock
Antunes, S; Alves, V.D.; Grandfils, Christian ULg et al

Conference (2013, September)

Detailed reference viewed: 8 (0 ULg)