Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailEffets de lisière et sex-ratio de rongeurs forestiers dans un écosystème fragmenté en République Démocratique du Congo (Réserve de Masako, Kisangani)
Iyongo Waya Mongo, L; De Cannière, C; Ulyel, J et al

in Tropicultura (2013), 31(1), 3-9

Detailed reference viewed: 17 (2 ULg)
Full Text
Peer Reviewed
See detailEffets de lisière sur la productivité du teck (Tectona grandis L.f.): étude de cas des teckeraies privées du Sud-Bénin
Toyi, Mireille Scholastique; Bastin, Jean-François ULg; Andre, Marie ULg et al

in Tropicultura (2013), 31(1), 62-70

The present study aims to improve the production of teak wood (Tectona grandis L.f.) in private plantations in southern Benin through the application of a central concept in landscape ecology: the edge ... [more ▼]

The present study aims to improve the production of teak wood (Tectona grandis L.f.) in private plantations in southern Benin through the application of a central concept in landscape ecology: the edge effect. As teak is an heliophilous species, the hypothesis of a higher wood production in edges was tested on the basis of the basal area. Sixty-two private teak plantations were investigated and 10,667 trees were measured. The stratified sampling scheme in three distinct parts for each plantation (the centre, the edge and the summits) permitted to highlight the edge effect on wood production. For each part, a plot was installed and the diameter at breast height (dbh) was measured for all trees. The leaf area between the edge and the centre of plantations was measured. Finally, the influence of the spatial configuration of plantations and the direction of each side of these plantations on the production of wood was tested. Results show that the edge effect on the production of teak wood affects four planting lines, the first presenting a production of 150% relative to the centre. We noticed a significant influence of the edge on the leaf area of about 218% relative to the centre. No influence of the direction of the sides of the plantation was observed. The shape of the plantations presents a significant influence on the wood production. These results permitted to propose a planting model included in an agroforestry system that optimizes the production of wood per area and having a succession of two planting lines interrupted by fields. [less ▲]

Detailed reference viewed: 42 (5 ULg)
Full Text
Peer Reviewed
See detailEffets de lisière sur la teneur en eau et la température du sol à l'échelle du jardin systématique de l'INERA/Yangambi en R.D. Congo
Alongo Longomba, S; Visser, M; Kombele Bishosha, F et al

in Annales des Instituts Supérieurs d’Etudes Agronomiques de Bengamisa (2013), 5

Detailed reference viewed: 16 (3 ULg)
Peer Reviewed
See detailEffets de parole vive. Poétique de la saynète dans la presse satirique illustrée des années 1830-1840
Stienon, Valérie ULg

in Thérenty, Marie-Ève; Pillet, Élisabeth (Eds.) Presse, chansons et culture orale au XIXe siècle. La parole vive au défi de l’ère médiatique (2012)

Detailed reference viewed: 18 (0 ULg)
Full Text
See detailEffets de retard et de piégeage des polluants dus à la présence d’eau immobile dans le milieu souterrain : importance de ces effets et modélisation
Brouyère, Serge ULg; Hallet, Vincent; Dassargues, Alain ULg

in Actes du Colloque National du CBGI/BCIG :’La Géologie de l’Ingénieur et l’eau dans le sous-sol’ (1997)

Detailed reference viewed: 28 (6 ULg)
Full Text
Peer Reviewed
See detailEffets de trois Alcaloides Extraits du Strychnos usambarensis sur des Cellules Cancereuses en Culture
Bassleer, Roger ULg; Gillet, Marie-Claire ULg; Massart, B. et al

in Planta Medica (1982), 45(6), 123-6

The cellular effects of three alkaloids isolated from STRYCHNOS USAMBARENSIS (melinonine F, strychnofoline, 18-19-dihydro-usambarine) are analysed by cytological methods in experimental animal tumours ... [more ▼]

The cellular effects of three alkaloids isolated from STRYCHNOS USAMBARENSIS (melinonine F, strychnofoline, 18-19-dihydro-usambarine) are analysed by cytological methods in experimental animal tumours cultivated IN VITRO (B 16 mouse melanoma cells, mouse Ehrlich tumour cells ELT, HW 165 rat hepatoma). Under some experimental conditions, a certain degree of antimitotic activity is demonstrated. [less ▲]

Detailed reference viewed: 38 (4 ULg)
Full Text
See detailLes effets délétères métaboliques et oxydants induits lors d'un sepsis sur la fonction rénale
Quoilin, Caroline ULg

Doctoral thesis (2014)

Acute kidney injury (AKI) is a frequent complication of sepsis that can increase mortality as high as 70%. The pathophysiology of this kidney failure was previously believed to be secondary to decreased ... [more ▼]

Acute kidney injury (AKI) is a frequent complication of sepsis that can increase mortality as high as 70%. The pathophysiology of this kidney failure was previously believed to be secondary to decreased global renal perfusion causing hypoxia-induced injury. However, new research suggests this paradigm is overly simplistic, and injury is now considered multifactorial in origin. Mechanisms that contribute to kidney injury mainly include inflammation, alterations in microvascular renal blood flow and changes in bioenergetics. To study the mechanism of oxygen regulation in acute kidney injury during sepsis, we developed a sepsis-induced in vitro model using proximal tubular epithelial cells (HK-2) exposed to a bacterial endotoxin (lipopolysaccharide, LPS). Our first investigation, by using both high-resolution respirometry and electron spin resonance spectroscopy, showed that HK-2 cells exhibit a decreased oxygen consumption rate when treated with LPS. Surprisingly, this cellular respiration alteration persists even after the stress factor is removed. We suggested that this irreversible decrease in renal oxygen consumption after LPS challenge is related to a pathologic metabolic down-regulation such as a lack of oxygen utilization by cells for ATP production. In the long term, this metabolic disturbance leads cells to a predominantly apoptotic death. To confirm this hypothesis of cytopathic hypoxia, we demonstrated that this alteration in the renal respiratory function is mainly due to an impairment in the metabolic activity of HK-2 cell mitochondria. Following LPS treatment, the oxidative phosphorylation is interrupted because of the inhibition of cytochrome c oxidase activity. As a consequence, disruptions in the electron transport and the proton pumping across the system occur, leading to a decrease of the mitochondrial membrane potential, the release of apoptotic-inducing factors and a decrease in ATP production. To clarify the mechanism by which the LPS induces mitochondrial alterations, we studied the oxidative stress generation in HK-2 cells. Interestingly, we revealed that the induction of a cytosolic oxidative stress is an event that appears before mitochondrial dysfunction in the LPS-treated HK-2 cells. This primary redox state is notably due to the activation of the two enzymes NADPH oxidase 4 and inducible NO synthase. The simultaneous production of anion superoxide and nitric oxide strongly suggests the formation of peroxynitrite, a relative stable powerful oxidant that can diffuse through mitochondrial compartments and undergo cytotoxic reactions. To our knowledge, our model reveals for the first time the role of NADPH oxidase-derived cytosolic ROS in triggering tubular cell damage. Moreover, after being first target of the oxidative stress, mitochondria become in turn producer of reactive oxygen species that carry on mitochondrial dysfunction. It seems thus that a mechanism of oxidative stress-induced redox cycling is a main cause of the mitochondrial dysfunction of LPS-treated HK-2 cells. The role of oxidants in mitochondrial dysfunction was further confirmed by the use of iNOS inhibitors or antioxidants that preserve cytochrome c oxidase activity and block mitochondrial membrane potential dissipation. Overall, these results suggest that sepsis-induced AKI should not only be regarded as failure of energy status but also as an integrated response, including transcriptional events, ROS signaling, mitochondrial activity and metabolic orientation such as apoptosis. [less ▲]

Detailed reference viewed: 64 (16 ULg)
Full Text
See detailEffets des antibiotiques sur le procédé d'épuration par boues activées. Etude du cas de l'érythromycine, du floc bactérien au réacteur biologique
Louvet, Jean-Noël ULg

Doctoral thesis (2010)

This study examines the effect of erythromycin on activated sludge bacteria and the inhibition of the pollution removal in batch reactors treating urban wastewater. Results showed the importance of ... [more ▼]

This study examines the effect of erythromycin on activated sludge bacteria and the inhibition of the pollution removal in batch reactors treating urban wastewater. Results showed the importance of exposure time to erythromycin. Inhibition of nitrification and COD removal was measured during a 4 h period for erythromytcin concentrations higher than 1 mg/L. A 4 µg/L erythromycin concentration inhibited COD removal during a 20 h exposure time. The effect of erythromycin on nitrification was variable depending on the sludge origin. Erythromycin inhibited the specific nitrification rate with sludge from Nancy WWTP, but increased the nitrification rate at the other facility (Epinal WWTP). The cell lysis resulted in destruction of activated sludge flocs. Microscopic techniques (epifluorescence and confocal laser scanning microscopy (CLSM)), combined with a fluorescent viability indicator, allowed us to study erythromycin time-kill activity.Viability staining results showed a latency time before the lower antibiotic concentrations began to kill bacteria. This latency time could be related to antibiotic adsorption and diffusion into activated sludge flocs as well as the rate of bateria death. The effect of erythromycin according to the bacterial Gram type was investigated with 3-dimensional Confocal Laser Scanning Microscopy (CLSM) time-lapse imaging combined with a Gram and Viability staining. Gram+ bacteria had a higher mortality rate than the Gram- bacteria. This result suggests that antibiotic in wastewater could change the activated sludge bacteria composition according to their Gram type by selecting bacteria the less sensitive to the antibiotics. [less ▲]

Detailed reference viewed: 87 (23 ULg)
Full Text
See detailLes effets des arrêts de la CJCE et du TPICE
Petit, Nicolas ULg; Defossez, Alexandre ULg

Conference (2008, May)

Detailed reference viewed: 94 (8 ULg)
Full Text
Peer Reviewed
See detailEffets des fibres et du type de sol sur les émissions de gaz à effet de serre et d'ammoniac associées à l’élevage de truies
Philippe, François-Xavier ULg; Laitat, Martine ULg; Wavreille, José et al

in 44èmes Journées de la Recherche Porcine (2012)

A study was carried out to investigate the effect of dietary fibre content (23% of non-starch polysaccharides (NSP) with a standard diet based on cereals vs. 44% of NSP with a fibrous diet based on sugar ... [more ▼]

A study was carried out to investigate the effect of dietary fibre content (23% of non-starch polysaccharides (NSP) with a standard diet based on cereals vs. 44% of NSP with a fibrous diet based on sugar beet pulp) and the floor type (slatted floor vs. straw-based deep litter) on emissions of ammonia (NH3), nitrous oxide (N2O), methane (CH4) and CO2-equivalents (Eq-CO2). Six successive batches of 10 gestating sows were divided into 2 groups kept in 2 experimental rooms differing by the floor type. The standard diet was administered to the sows of the first 3 batches, the fibrous diet to the sows of the next 3 batches. Emissions were measured by infra-red photoacoustic detection. With the slatted floor, the fibrous diet decreased NH3 emission (12.0 vs. 15.5 g sow-1.d-1) but increased the Eq-CO2 emissions (0.69 vs. 0.57 kg sow-1.d-1) in relation to an increase of CH4 emissions (18.4 vs. 12.8 g sow-1.d-1), the N2O emissions not being impacted by the diet, with value around 0.62 g sow-1.d-1. With the straw-bedded floor, the fibrous diet increased the emissions of NH3 (12.3 vs. 9.2 g sow-1.d-1) and CH4 (14.6 vs. 9.6 g sow-1.d-1) but decreased N2O emissions (0.99 vs. 1.64 g/ sow-1.d-1) with the consequence that Eq-CO2 emissions were similar for the two diets, around 0.74 kg sow-1.d-1. [less ▲]

Detailed reference viewed: 56 (32 ULg)
See detailEffets des mesures alternatives pour les consommateurs de drogues
De Ruyver, Brice; Ponsaers, Paul; Lemaître, André ULg et al

Book published by Academia Press (2007)

Detailed reference viewed: 33 (5 ULg)