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Peer Reviewed
See detailInfluence of some heat treatments parameters on the microstructure of high alloyed steels
Lecomte-Beckers, Jacqueline ULg; Tchuindjang, Jérôme Tchoufack ULg

in Proceedings of the MSMF-3 International Conference (2001)

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See detailInfluence of source and levels of dietary fiber on in vivo nitrogen excretion pathways in pigs and in vitro fermentation and protein synthesis by fecal bacteria
Bindelle, Jérôme ULg; Buldgen, André; Delacollette, Maud et al

in Journal of Animal Science (2009), 87

The inclusion of dietary fiber (DF) in diets has been suggested as a way to reduce ammonia emission in pig barns because it contributes to a shift in N excretion from urine to feces due to enhanced ... [more ▼]

The inclusion of dietary fiber (DF) in diets has been suggested as a way to reduce ammonia emission in pig barns because it contributes to a shift in N excretion from urine to feces due to enhanced bacterial growth in the intestines. This study compared an in vitro method to measure bacterial protein synthesis during fermentation to in vivo N excretion shift induced by diets differing in DF concentrations and solubility. The first experiment measured the effect of graded concentrations of sugar beet pulp (SBP; 0, 10, 20 and 30%) in corn-soybean meal-based diets on in vivo N excretion partitioning between urine and feces. A second experiment investigated the replacement of SBP, rich in soluble DF, by oat hulls (OH), rich in insoluble DF (20:0; 10.5:10.5; 0:22%, respectively). In parallel, the fermentation characteristics of the dietary carbohydrates not digested in the small intestine was evaluated in an in vitro gas test, based on their incubation with colonic microbiota, using a mineral buffer solution enriched with 15N. The N originating from the buffer solution incorporated into the bacterial proteins (BNI) was measured when half of the final gas volume was produced (T/2: 8.5 to 14.5 h of fermentation) and after 72 h of fermentation. Short-chain fatty acids (SCFA) were determined in the liquid phase. In the first experiment, the inclusion of SBP linearly decreased urinary N excretion from 0.285 to 0.215 g N excreted in urine per g N ingested and urinary-N:fecal–N excretion ratio from 2.171 to 1.177 (P < 0.01). In the second experiment, the substitution of SBP by OH linearly increased urinary-N:fecal–N excretion ratio (P = 0.009). Unlike SCFA production, BNI was greater at T/2 than at 72 h of fermentation. Sugar beet pulp enhanced BNI linearly (P < 0.001): 2.01, 2.06 and 2.35 mg g-1 diet with 10, 20 and 30% SBP, respectively, as compared to 1.51 mg for the control diet. The substitution of SBP by OH decreased BNI (P < 0.01). With the exception of final gas production, all in vitro kinetics characteristics and BNI were correlated to in vivo N excretion parameters and regression equations for the prediction of N excretion pathways from in vitro data were identified. Even if the presence of resistant starch in the diet might alter the composition of the fibrous residue that is fermented, it can be concluded that the in vitro method is a possible useful tool for the formulation of diets reducing the effects of pig production on the environment. [less ▲]

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See detailThe influence of source similarity on memory accuracy
Dehon, Hedwige ULg

Poster (2006)

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See detailThe influence of Space Weather and of the ionosphere on Global Navigation Satellite Systems
Warnant, René ULg; Jodogne, Jean-Claude; Nebdi, Hamid

Conference given outside the academic context (2002)

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See detailThe influence of Space Weather and of the ionosphere on Global Navigation Satellite Systems
Warnant, René ULg; Jodogne, Jean-Claude; Nebdi, Hamid

Conference (2002)

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See detailInfluence of space-filling materials in subantral bone augmentation: blood clot vs. autogenous bone chips vs. bovine hydroxyapatite
Lambert, France ULg; Léonard, Angélique ULg; Drion, Pierre ULg et al

in Clinical Oral Implants Research (2011), 22(5), 538-545

Aim: The first objective of the present study was to compare the short- and long-term 3D volume stability of sub-sinusal bone regeneration in rabbits using different space fillers. The second objective ... [more ▼]

Aim: The first objective of the present study was to compare the short- and long-term 3D volume stability of sub-sinusal bone regeneration in rabbits using different space fillers. The second objective was to assess qualitatively and quantitatively the early bone formation process and long-term behavior of the regenerated bone. Materials and methods: Fifteen rabbits underwent a double sinus lift procedure using: blood clot (Clot), autogenous bone chips (Auto) and bovine hydroxyapatite (BHA). Animals were euthanized at 1 week, 5 weeks and 6 months. Samples were subjected to X-ray microtomography and histology. Variations in the volume of bone augmentations were calculated at different time points. Qualitative analysis was performed using 7 μm sections and quantitative histomorphometric analyses were carried out using scanning electron microscopy. Results: From baseline (100%) to 5 weeks, the augmented volumes declined to 17.3% (Clot), 57.6% (Auto) and 90.6% (BHA). After 6 months, only 19.4% (Clot) and 31.4% (Auto) of initial volumes were found, while it remained more stable in the BHA group (84%). At 1 week, an initial osteogenesis process could be observed in the three groups along the bone walls. At 5 weeks, despite a significant decline in the volume, newly formed bone density was higher with Clot and Auto than with BHA. At 6 months, bone densities were statistically similar in the three groups. However, after 6 months, the surface invaded by newly formed bone (regenerated area) was significantly higher when BHA was used as space filler. In the BHA group, the biomaterial area slightly decreased from 42.7% (1 week) to 40% (5 weeks) and 34.9% (6 months) and the density of the composite regenerated tissue (bone+BHA) reached >50% at 6 months. Conclusions and clinical implications: The three space fillers allowed bone formation to occur. Nevertheless, augmented volumes declined in the Clot and Auto groups, while they remained stable with BHA. A slowly resorbable biomaterial might be suitable in sub-sinusal bone augmentation for preventing the re-expansion process and for augmenting the density of the regenerated tissues. [less ▲]

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See detailThe influence of spatially structured soil properties on tree community assemblages at a landscape scale in the tropical forests of southern Cameroon
Vleminckx, Jason; Doucet, Jean-Louis ULg; Morin, Julie ULg et al

in Journal of Ecology (2016)

Species distribution within plant communities results from both the influence of deterministic processes, related to environmental conditions, and neutral processes related to dispersal limitation and ... [more ▼]

Species distribution within plant communities results from both the influence of deterministic processes, related to environmental conditions, and neutral processes related to dispersal limitation and stochastic events, the relative importance of each factor depending on the observation scale. Assessing the relative contribution of environment necessitates controlling for spatial dependences among data points. Recent methods, combining multiple regression and Moran's eigenvectors maps (MEM), have been proved successful in disentangling the influence of pure spatial processes related to dispersal limitation, pure environmental variables (not spatially structured) and spatially structured environmental properties. However, the latter influence is usually not testable when using advanced spatial models like MEM. To overcome this issue, we propose an original approach, based on torus-translations and Moran spectral randomizations, to test the fraction of species abundance variation that is jointly explained by space and seven soil variables, using three environmental and tree species abundance data sets (consisting of 120, 52 and 34 plots of 0·2 ha each, located along 101-, 66- and 35-km-long transect-like inventories, respectively) collected in tropical moist forests in southern Cameroon. The overall abundance of species represented by ≥30 individuals, and 27% of these species taken individually, were significantly explained by fine-scale (<5 km) and/or broad-scale (5–100 km) spatially structured variations in soil nutrient concentrations (essentially the concentration of available Mn, Mg and Ca) along the 120-plots area. The number of significant tests considerably decreased when investigating the two smaller data sets, which mostly resulted from low statistical power rather than weaker floristic and/or edaphic variation captured among plots. Synthesis. Our results provide evidence that tree species turnovers are partly controlled by spatially structured concentrations in soil nutrients at scales ranging from few hundreds of metres to c. 100 km, a poorly documented subject in Central African forests. We also highlight the usefulness of our testing procedure to correctly interpret the space-soil fraction of variation partitioning analyses (which always accounted here for the most important part of the soil contribution), as this fraction was sometimes relatively high (R2 values up to c. 0·3) but nearly or not significant. [less ▲]

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See detailInfluence of Specific Anti-Salmon Calcitonin Antibodies on Biological Effectiveness of Nasal Salmon Calcitonin in Paget's Disease of Bone
Reginster, Jean-Yves ULg; Gennari, C.; Mautalen, C. et al

in Scandinavian Journal of Rheumatology (1990), 19(1), 83-6

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See detailInfluence of specific rehabilitation programs on pressure pain thresholds in patients with fibromyalgia or chronic low back pain
Maquet, Didier ULg; Demoulin, Christophe ULg; Lecart, Marie-Paule ULg et al

in Annals of the Rheumatic Diseases (2007), 66

Background: Specific rehabilitation programs are recommended in chronic pain syndromes. The subjective experience and multidimensional nature of pain is problematic for assessment. Pressure pain threshold ... [more ▼]

Background: Specific rehabilitation programs are recommended in chronic pain syndromes. The subjective experience and multidimensional nature of pain is problematic for assessment. Pressure pain threshold (PPT) is defined as the minimum force applied which induces pain measured with a dolorimeter. Objectives: The purposes were: (1) to compare PPTs for 18 specific tender sites in patients with fibromyalgia (FM) and in patients with chronic low back pain (CLBP), (2) to assess the PPT changes in these groups following specific rehabilitation programs. Methods: Eleven women with CLBP and six women with FM were included in this study. They attended biweekly specific multidisciplinary rehabilitation sessions for 8 weeks. Pain intensity and PPTs for the 18 specific tender sites defined by the American College of Rheumatology were evaluated respectively with a visual analogue scale (VAS) and with an electronic dolorimeter, before and after the programs. Normative data of PPTs were established in a recent study [1]. Results: Before starting the rehabilitation program, patients with FM displayed VAS scores higher (p<0.05) than those with CLBP. Furthermore, FM patients had the lowest (p<0.05) PPTs over all examined areas. Statistical analysis failed to show any differences between PPTs of CLBP and healthy subjects. At the end of the specific program, VAS scores decreased significantly in both patient groups. In contrast, a significant increase of PPTs was only observed in FM patients. However, their PPTs remained below the CLBP and healthy PPT values. Conclusion: Despite the presence of chronic pain in these two syndromes, the decrease of PPTs appears to be specific in patients with FM. Measure of PPTs could represent a relevant method in order to perform a longitudinal follow-up of patient's pain perception. After the rehabilitation programs, pain intensity decreased in both patient groups. References: [1] Maquet D, Croisier JL, Demoulin C, Crielaard JM. Pressure pain thresholds of tender point sites in patients with fibromyalgia and in healthy controls. Eur J Pain, 2004, 8:111-117. [less ▲]

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See detailThe influence of specific training on the plyometric profile
Jidovtseff, Boris ULg; Harris, Nigel; Carpent, Nicolas et al

Poster (2016, November 30)

Sprinting, jumping and change of direction involve the stretch-shorten cycle (SSC) and therefore plyometric training is used to improve these factors. It has been demonstrated that the jumping strategy ... [more ▼]

Sprinting, jumping and change of direction involve the stretch-shorten cycle (SSC) and therefore plyometric training is used to improve these factors. It has been demonstrated that the jumping strategy utilized can influence the biomechanical profile of the exercise and subsequent adaptation. For example, in some cases, it is important to jump as high as possible while in other cases it is important to reduce the ground contact time. Our hypothesis is that the choice of plyometric exercise has to be matched to the desired biomechanical adaptation. Hence we investigated the influence of 8 weeks of different programs on the plyometric profile of recreational athletes. In each of five groups, very specific exercises were selected according to the training objective: ground contact time group (CT, n=9); vertical jump height group (JH, n=9); CT and JH combination group (CT-JH, n=11); JH + strength training group (JH-S, n=9); and control group (CO, n=8). The plyometric profile performed prior to and post training included measures of jump height, contact time, stiffness and reactivity at different bounding intensities. The results demonstrated that JH and JH-S programs were more effective for improving jump height performance (+7-9%; p<0.005) compared to insignificant jump height changes in the CT and CO groups. CT-JH was the most effective on the reactivity index (+14%, p<0.005) although significant increases (+8%, p<0.05) were also observed in CT, JH and JH-S groups. CT was the only group to significantly decrease short contact time (-5%, p<0.05). ANOVA analysis revealed significant groups*session effect for jump height (p<0.01) and reactivity (p<0.005) but not for short contact time. The present study confirms that the principle of specificity is fundamental in plyometric training so the exercise selection should be developed cognizant of intended adaptations. Jump height and reactivity appear to be differentially affected by specific training practices. [less ▲]

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See detailInfluence of Sport Activity on Trunk Muscle Performances
Grosdent, Stéphanie ULg; Demoulin, Christophe ULg; Coupas, Amandine et al

Poster (2010, June 24)

Introduction: Lumbar pain among athletes is a common problem and can be challenging for athletic trainers and therapists. Unfortunately, little is known about the capabilities of trunk muscle function in ... [more ▼]

Introduction: Lumbar pain among athletes is a common problem and can be challenging for athletic trainers and therapists. Unfortunately, little is known about the capabilities of trunk muscle function in elite athletes Therefore, an objective assessment of muscle performance is relevant in injury prevention and rehabilitation. The purpose of this study was to examine the specific trunk muscle strength and endurance in different sports i.e. swimming, rowing and tennis. Methods: We assessed maximum isometric trunk extensor, rotator, flexor and lateroflexor muscle strength as well as trunk extensor muscle endurance of 10 swimmers, 10 rowers, 10 tennismen and 10 sedentary students (control group). Strength was measured by means of specific trunk dynamometers. An adaptation of the Sorensen test was performed to assess trunk extensor endurance. Results: Muscle strength appeared generally higher among athletes than among control subjects. However, differences were statistically significant only with swimmers for trunk flexors (p<0.05) and trunk rotators (p<0.05), with rowers for trunk flexors (p<0.05) and with tennismen for dominant lateroflexors (p<0.05) and non-dominant trunk rotators (p<0.05). No significant bilateral difference appeared for trunk lateralflexors strength. For trunk rotators, tennismen were significantly stronger in the non-dominant side (p<0.05). Trunk extensor endurance was higher among rowers than among the other groups. Conclusion: This study underlined several differences in trunk muscle performance between athletes and control subjects as well as within athletes groups in relation to their sports. Further studies would clarify the full significance of these results with respect to performance and injury. [less ▲]

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See detailInfluence of stage of maturity of maize silage on animal performance
Dufrasne, Isabelle ULg; Istasse, Louis ULg; Gielen, Marc ULg et al

in Proceedings of the 42nd Annual Meeting of E.A.A.P (1991)

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See detailInfluence of steam explosion and thermal degradation of cellulose
Jacquet, Nicolas ULg; Quiévy, Nicolas; Vanderghem, Caroline ULg et al

Poster (2010, August 20)

The aim of the present work is to compare the effect of different steam explosion pretreatments on the thermal degradation of a bleached cellulose where components like hemicelluloses and lignin have ... [more ▼]

The aim of the present work is to compare the effect of different steam explosion pretreatments on the thermal degradation of a bleached cellulose where components like hemicelluloses and lignin have already been removed by acid and alkaline treatments. The results of this study show that thermal degradation of cellulose fibres, studied by TGA, is still limited for a temperature process below 240 °C. However, derivative TGA show that thermal stability of cellulose obtained by these conditions decreases with the increase of temperature. For temperatures above 250°C, char level is higher at the end of the pyrolysis. According to the literature, the increase of the char level is correlated to an increase of the degradation product1. Determination of the degradation products in the liquor obtained after the pretreatment show an important increase of furfural and 5-hydroxymethylfurfural concentration with the temperature in agreement with the increase of the char level. These results confirm the important degradation of the cellulose fibres. [less ▲]

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See detailINFLUENCE OF STEAM EXPLOSION ON CRYSTALLINITY PROPERTIES OF PURE CELLULOSE FIBER
Jacquet, Nicolas ULg; Vanderghem, Caroline ULg; Danthine, Sabine ULg et al

Poster (2012, March 01)

The aim of the present study is to compare the effect of different steam explosion treatments on crystallinity properties of a pure bleached cellulose. Steam explosion process is composed of two distinct ... [more ▼]

The aim of the present study is to compare the effect of different steam explosion treatments on crystallinity properties of a pure bleached cellulose. Steam explosion process is composed of two distinct stages: vapocracking and explosive decompression. The treatment intensities is determined by a severity factor, established by a correlation between temperature process and retention time. The results show that steam explosion treatment has an impact on the crystallinity properties of pure cellulose fiber. When the severity factor is below 5.2, an increase of the overall crystallinity of the samples is observed with the treatment intensities. For higher intensities, a significant thermal degradation of cellulose lead to an important change in substrate composition, which lead to a further decrease of cellulose crystallinity [less ▲]

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See detailInfluence of steam explosion on physico-chemical properties and hydrolysis rate of pure cellulose fibers
Jacquet, Nicolas ULg; Vanderghem, Caroline ULg; Danthine, Sabine ULg et al

in Bioresource Technology (2012), 121(221-227),

The aim of the present study is to compare the effect of different steam explosion treatments on physicochemical properties and hydrolysis rate of a pure bleached cellulose. The results showed that ... [more ▼]

The aim of the present study is to compare the effect of different steam explosion treatments on physicochemical properties and hydrolysis rate of a pure bleached cellulose. The results showed that moderate steam explosion treatments (severity factor below 5.2) did not improve the enzymatic hydrolysis rate of the cellulose fibers. The characterization of the obtained samples showed an increase of the cellulose accessibility coupled with an increase of the overall crystallinity of the substrate. In these conditions, the higher accessibility is counterbalanced by the increased crystallinity. Indeed, a greater proportion of the substrat is accessible by only a fraction of the enzymatic complex (exo-glucanases) activities. When the severity factor reached 5.2, a decrease of the cellulose enzymatic hydrolysis rate was observed. In this case, TGA analysis showed an increase of the char level at the end of the pyrolysis which traduced an important thermal degradation of the samples. The thermal degradation of cellulose lead to an important change in substrate composition, which induced a decrease of the cellulose ratio available for hydrolysis and caused a decrease of the hydrolysis yields. [less ▲]

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See detailInfluence of steam explosion on the thermal stability of cellulose fibres
Jacquet, Nicolas ULg; Quievy, Nicolas; Vanderghem, Caroline ULg et al

in Polymer Degradation & Stability (2011), 96

The aim of the present study was to compare the effect of different steam explosion treatments on the thermal degradation of a bleached cellulose. The intensity of a steam explosion treatment, which ... [more ▼]

The aim of the present study was to compare the effect of different steam explosion treatments on the thermal degradation of a bleached cellulose. The intensity of a steam explosion treatment, which allows breakdown of the structural lignocellulosic material was determined by a correlation between time and temperature of the process. Results of this study showed that thermal degradation of cellulose fibres was limited when the severity factor applied was below 4.0. For higher intensities, determination of the degradation products in the water-soluble extract showed an important increase of the 5-hydroxymethyl-furfural concentration with the temperature. When the severity factor reached 5.2., TGA analysis showed that the increase of degradation products was coupled to an increase of the char level meaning a strong degradation of the cellulose. dTGA behaviour also showed that thermal stability of the steam explosion samples decreased with the intensity of the treatment. To conclude, a theoretical diagram predicting the degradation of the cellulose during the steam explosion treatment was established. [less ▲]

Detailed reference viewed: 133 (41 ULg)