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 detailInfluence of the cardiac cycle on time-intensity curves using multislice dynamic magnetic resonance perfusion
NCHIMI LONGANG, Alain ULg; MANCINI, Isabelle; BROUSSAUD, Thomas K. Y.

in International Journal of Cardiovascular Imaging (The) (2014), 30

Flow and pressure variations cause potential changes in magnetic resonance imaging (MRI) signal intensity across the cardiac cycle. Nevertheless, cardiac dynamic contrast-enhanced (perfusion) MRI is ... [more ▼]

Flow and pressure variations cause potential changes in magnetic resonance imaging (MRI) signal intensity across the cardiac cycle. Nevertheless, cardiac dynamic contrast-enhanced (perfusion) MRI is performed and analyzed regardless of the cardiac phase. We investigate whether the cardiac phase impacts myocardial and left ventricle (LV) cavity time intensity curves (TICs) at rest and during vasodilatation. Fifteen healthy volunteers (seven females, eight males; mean age: 32.5 ± 9.3 years; age range: 19–49 years) were included in this prospective study. They underwent four separate short-axis multislice (apical, mid and basal) LV perfusion MRI, with different electrocardiogram-triggering during normal vasotone and adenosine-stress. TIC parameters were extracted from the myocardium and the LV cavity. General linear mixed model analyses were used to evaluate their variability according to vasotone, cardiac phase and slice-position. Maximal enhancement and normalized Steepest slopes were higher at stress than at rest (p values <0.001). A similar trend towards higher inflow was shown on systole versus diastole in the LV cavity and diastole versus systole in the myocardium (p < 0.05).These TIC parameters were slice-position dependent, as the inflow decreased from the base to the apex in the LV, and peaked on the mid-slice for the myocardium. There are significant variability of both the LV and the myocardial TICs, with respect to the cardiac cycle phase and the slice position where imaging actually takes place. These appeal to measurement standardization for a better intra- and inter-study reproducibility. [less ▲]

Detailed reference viewed: 45 (1 ULg)
Full Text
Peer Reviewed
See detailInfluence of the chemical composition on the thixoformability of steels
Pierret, Jean-Christophe ULg; Rassili, Ahmed ULg; Vaneetveld, Grégory ULg et al

in International Journal of Material Forming (2009)

This work deals with the qualification of a variety of steels for their shaping by the thixoforging process. This technology requires setting up a globular microstructure inside the material during ... [more ▼]

This work deals with the qualification of a variety of steels for their shaping by the thixoforging process. This technology requires setting up a globular microstructure inside the material during reheating to a temperature between the solidus and liquidus. As the evolution of the liquid fraction is strongly connected to the steel composition, it is useful to understand how low carbon steel could be alloyed and still thixoformable. The most critical parameter for this is the carbon content. In this study, a theoretical analysis of the phase evolution during the reheating has been performed on the MT Data software to investigate the influence of alloying elements. These first results have been confirmed by Differential Thermal Analysis and by inductive heating experiments on steel slugs. Finally, some parts have been shaped using a thixoforming tool mounted on a hydraulic press. Micrographs of reheated slugs as well as of actual parts are also presented in this paper. [less ▲]

Detailed reference viewed: 39 (10 ULg)
Full Text
Peer Reviewed
See detailInfluence of the composition of the repairing mortars on adherence
Courard, Luc ULg; Wiertz, Jean; Darimont, Anne ULg et al

in Van Gemert, Dionys (Ed.) Proceedings of the VIIIth International Congress on Polymers in Concrete (1995)

Detailed reference viewed: 8 (1 ULg)
Full Text
Peer Reviewed
See detailInfluence of the contraction mode on the tendon structure - Rat model
Kaux, Jean-François ULg; Drion, Pierre ULg; Besançon, Benoît et al

in 2nd Congress of European College of Sport & Exercise Physicians - Conference Brochure 2010: Abstracts and CVs (2010, September 09)

Introduction: Tendinopathies are common in sport and affect both upper and lower limbs. Eccentric rehabilitation is a successful way of treating them and now is becoming the “gold treatment”. Although ... [more ▼]

Introduction: Tendinopathies are common in sport and affect both upper and lower limbs. Eccentric rehabilitation is a successful way of treating them and now is becoming the “gold treatment”. Although clinical results are very favorable, beneficial morphological and histological effects have not yet been elucidated. The aim of our experiment was to determine if there exist any intrinsic modifications in a tendon trained in concentric or eccentric modes, in a rat model. Methods: 18 rats were divided into 3 groups: 6 for the control group, without physical restraint; 12 for a training of1 hour, 3 times a week, for 5 weeks, at a speed of 17m/min (1km/h), on a inclined treadmill: 6 rats running uphill at +15° for the concentric effort (group C) and 6 rats running downhill at -15° for the eccentric effort (group E). After this training period, the Achilles, patellar and tricipital tendons of both limbs were surgically removed in all 18 rats. Tendons taken from five rats of each group were subjected to a tensile test up to rupture using a “cryo” jaw. Tendons of the remaining rat of each group were subjected to a histological study. Results: The results showed significant changes in group E only: (1) an increase of the force required to rupture the patellar and tricipital tendons; (2) an improvement of the ratio between the force necessary to rupture the tricipital tendon and the body mass of the rats; (3) an increase of the surface area of the section of the tricipital tendon. No significant change was observed as far as constraint was concerned between groups. Histologically, we saw, in the group E, more peripheral blood vessels and a greater proportion of collagen. Conclusion: This study showed that the mechanical properties of tendon tissue are enhanced by eccentric training. Tendons become stronger, the amount of collagen increases and there is probably more interaction between collagen fibers (mechanotransduction). [less ▲]

Detailed reference viewed: 57 (7 ULg)
Full Text
Peer Reviewed
See detailInfluence of the convective flux perturbation on stellar oscillations: application to Delta Scuti and Gamma Doradus stars
Grigahcene, A.; Dupret, Marc-Antoine ULg; Garrido, R. et al

in Communications in Asteroseismology (2004), 145

We present a theory of convection-oscillation interaction. In our nonradial nonadiabatic pulsation code, the variation of the convective flux (radial and transversal components) is taken into account ... [more ▼]

We present a theory of convection-oscillation interaction. In our nonradial nonadiabatic pulsation code, the variation of the convective flux (radial and transversal components) is taken into account, following the theory of M. Gabriel, within the mixing length approach. We explore the influence of the convective flux variation on mode stability near the red-edge of the Delta Scuti instability strip and the excitation mechanisms of Gamma Doradus stars. [less ▲]

Detailed reference viewed: 11 (0 ULg)
Peer Reviewed
See detailInfluence of the core on the 3d orbital before and after the collapse
Hansen, J E; Meyer, M; Sonntag, B et al

in Atomic and Molecular Photoionization (1996)

Detailed reference viewed: 19 (0 ULg)
Full Text
Peer Reviewed
See detailInfluence of the Counterpoise Correction on the Optimized Relativi Degrees of Freedom in the H-Bonded Complex Water-Formamide
Dehareng, Dominique ULg; Dive, Georges ULg; Ghuysen, Jean-Marie ULg

in Theoretica Chimica Acta (1992), 81(4-5), 281-290

The correction of the basis set superposition error by the counterpoise method has been investigated at the SCF level for the weak H-bonded water-formamide complex and the results have been compared with ... [more ▼]

The correction of the basis set superposition error by the counterpoise method has been investigated at the SCF level for the weak H-bonded water-formamide complex and the results have been compared with the uncorrected results at the SCF, post SCF and semi-empirical AM1 and MNDO levels. Our particular concern has been the determination of the three optimized relative degrees of freedom and the relative stability of three C(s) geometrical conformations. The conclusions are that the counterpoise correction weakly conditions the variation in the degrees of freedom and the relative stabilities of the three conformers. The correction is obviously inadequate to describe intramolecular deformation. [less ▲]

Detailed reference viewed: 21 (2 ULg)
See detailInfluence of the culture conditions on lipopeptide production by Bacillus subtilis
Akpa, E.; Jacques, Ph.; Fuchs, R. et al

Poster (2000, May)

Detailed reference viewed: 31 (1 ULg)
Full Text
Peer Reviewed
See detailINFLUENCE OF THE DAILY DISTRIBUTION OF LIGHT ON REPRODUCTION IN THE BARBEL, BARBUS-BARBUS (L)
Poncin, Pascal ULg

in Journal of Fish Biology (1992), 41(6), 993-997

Detailed reference viewed: 20 (1 ULg)
Full Text
Peer Reviewed
See detailInfluence of the dose and the number of drug-context pairings on the magnitude and the long-lasting retention of cocaine-induced conditioned place preference in C57BL/6J mice
Brabant, Christian ULg; Quertemont, Etienne ULg; Tirelli, Ezio ULg

in Psychopharmacology (2005), 180(1), 33-40

Rationale: The place conditioning procedure is increasingly used to study relapse in drug seeking in mice. However, the retention course of drug-induced place preference has not been systematically ... [more ▼]

Rationale: The place conditioning procedure is increasingly used to study relapse in drug seeking in mice. However, the retention course of drug-induced place preference has not been systematically characterized. Methods: The effects of cocaine doses and number of conditioning trials on both the magnitude and the persistence of cocaine-induced conditioned place preference (CPP) were investigated in C57BL/6J mice. Twelve groups of animals were injected with saline, 4, 8 or 12 mg/kg cocaine (i.p.) and submitted to an unbiased counterbalanced place conditioning protocol including one, two or four drug-pairing sessions. Subsequently, the animals were tested at various time intervals after the last conditioning session. Results: One cocaine-pairing session was insufficient to induce a CPP. Two and four pairing sessions resulted in significant place preferences of similar magnitude for all tested doses of cocaine, the place preference induced by the greatest number of pairing sessions being the strongest. In the two-pairing groups, place preference lasted less than 14 days for any tested dose of cocaine. In contrast, all four-pairing groups still showed significant place preference 28 days after the last conditioning session. However, the magnitude of cocaine place preference slowly declined at a rate that was dependent upon cocaine dose. On the 35-day post-conditioning interval, only the 12-mg/kg cocaine group still displayed a significant place preference, whereas place preference was undetectable at 42 and 56 days post-conditioning for all groups. Conclusions: The number of cocaine-pairing sessions, but not cocaine dose, affected the magnitude of cocaine place preference in mice when tested 1 day after the last conditioning session. In contrast, both cocaine doses and the number of pairing sessions affected the persistence of cocaine place preference. Overall, these results demonstrate that cocaine-induced place preference is a long lasting phenomenon that is strongly affected by the number of drug-pairing trials. [less ▲]

Detailed reference viewed: 20 (5 ULg)
Full Text
Peer Reviewed
See detailInfluence of the dynamometer and knee joint axis of rotation alignment on the isokinetic measurements
Croisier, Jean-Louis ULg; Ciavatta, P.; Forthomme, Bénédicte ULg

in Isokinetics & Exercise Science (2005, March), 13(1), 3-4

Detailed reference viewed: 36 (5 ULg)
Full Text
See detailInfluence of the elasto-plastic adhesive contact on Micro-Switches
Wu, Ling ULg; Golinval, Jean-Claude ULg; Noels, Ludovic ULg

in Hogge, Michel; Van Keer, Roger; Dick, Erik (Eds.) et al Proceedings of the 5th International Conference on Advanded COmputational Methods in Engineering (ACOMEN2011) (2011, November)

Undesirable stiction, which results from contact between surfaces, is a major failure mode in micro,electro-mechanical systems (MEMS). In previous works, a statistical rough surfaces interaction,model ... [more ▼]

Undesirable stiction, which results from contact between surfaces, is a major failure mode in micro,electro-mechanical systems (MEMS). In previous works, a statistical rough surfaces interaction,model, based on Maugis and Kim formulations has been presented to estimate the adhesive forces in MEMS switches. In this model, only elastic adhesive contact has been considered. However, during the impact between rough surfaces, at pull-in process for example, plastic deformations of the rough surfaces cannot be always neglected especially for the MEMS with metallic contact surfaces. In the present work, a new micro-model predicting the adhesive-contact force on a single elasticplastic asperity interacting with a rigid plane is presented. This model will be used later on for the interaction between two elastic-plastic rough surfaces. The MEMS devices studied here are assumed to work in a dry environment. In these operating conditions only the Van der Waals forces have to be considered for adhesion. [less ▲]

Detailed reference viewed: 33 (5 ULg)
Peer Reviewed
See detailInfluence of the equations of state and of the z value on the solar oscillations
Shibahashi, H.; Noels-Grötsch, Arlette ULg; Gabriel, Maurice ULg

in Memorie della Società Astronomica Italiana : Journal of the Italian Astronomical Society (1984), 55

The authors have evolved the standard solar models taking account of the electrostatic correction in the equations of state and the Los Alamos Opacity Library, and computed their eigenfrequencies for p ... [more ▼]

The authors have evolved the standard solar models taking account of the electrostatic correction in the equations of state and the Los Alamos Opacity Library, and computed their eigenfrequencies for p-mode and g-mode oscillations. The contribution of that correction to the pressure is up to several percent in the convective zone, and the present equilibrium models thus obtained have deeper convective zones than the conventional models. These improvements in the equilibrium model reduce the discrepancies between the theoretical frequencies and the observations concurrently for p-mode oscillations with low and high degree l. Theoretical frequencies of g-modes with low l are significantly higher than the observational ones. [less ▲]

Detailed reference viewed: 11 (4 ULg)
Full Text
Peer Reviewed
See detailInfluence of the estrous cycle on urodynamic and morphometric measurements of the lower portion of the urogenital tract in dogs
Hamaide, Annick ULg; Verstegen, John; Snaps, Frédéric ULg et al

in American Journal of Veterinary Research (2005), 66(6), 1075-1083

OBJECTIVES: To compare the values of the urodynamic parameters of the lower portion of the urinary tract and vaginourethral measurements obtained during the phases of the estrous cycle in dogs and ... [more ▼]

OBJECTIVES: To compare the values of the urodynamic parameters of the lower portion of the urinary tract and vaginourethral measurements obtained during the phases of the estrous cycle in dogs and determine possible functional or anatomic modifications of the lower portion of the urinary tract associated with those phases. ANIMALS: 7 adult female Beagles. PROCEDURE: Urethral pressure profilometry, diuresis cystometry, and vaginourethrography were performed in each dog during proestrus; estrus; early, mid, and late diestrus; and early and late anestrus. The maximum urethral pressure (MUP), maximum urethral closure pressure (MUCP), urethral functional and anatomic profile lengths (UFPL and UAPL, respectively), integrated pressure, threshold pressure, threshold volume, compliance, urethral length, and vaginal length and width were measured. RESULTS: For all measurements, significant interindividual variation was detected. Integrated and threshold pressures, APL, and each morphometric value significantly increased from late anestrus to proestrus. Compared with other phases, MUP, MUCP, and integrated pressure values were significantly lower in estrus and early diestrus; UAPL and UFPL values were significantly lower in late diestrus. At each cycle phase in old dogs, MUP, MUCP, threshold pressure, and vaginal length and width were significantly lower (except in proestrus for vaginal measurements) and threshold volume and compliance values were significantly higher, compared with middle-aged dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Urodynamic and morphometric measurements of the lower portion of the urogenital tract are affected by the changes in hormonal balance that occur during the estrous cycle. In sexually intact female dogs, estrous phase determination is important for the interpretation of urodynamic data. [less ▲]

Detailed reference viewed: 32 (7 ULg)
Full Text
Peer Reviewed
See detailInfluence of the fertilization type, the day in the paddock and the month on nitrogen rejections in dairy cows
Dufrasne, Isabelle ULg; Istasse, Louis ULg; Robaye, Vincent ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2010), 14

Influence of the fertilization type, the day in the paddock and the month on nitrogen rejections in dairy cows. The present study aims to quantify nitrogen (N) rejections in dairy cows on a rotational ... [more ▼]

Influence of the fertilization type, the day in the paddock and the month on nitrogen rejections in dairy cows. The present study aims to quantify nitrogen (N) rejections in dairy cows on a rotational grazing system with different types of fertilization (compost, slurry and mineral N) at two different days in the paddock (days 3 and 5) and during two different periods (June and September). Grass yield and height were measured along with the chemical composition. The live weight was recorded when the cows moved into the paddock and milk yields was recorded at each milking. N intakes were measured on the basis of the energy requirement. When the cows were in the paddocks, individual samples of faeces and urine were collected to assess N rejections. The urea content in milk from the tank or from the individual cows was also measured. N intake was higher on day 3 than on day 5 and in September as compared with in June but was not influenced by the fertilization. The amount of N produced in milk was not influenced either by the fertilization, by the day on the paddock or by the month. The amount of urinary N was significantly higher in the N mineral group than in the two other groups. The N excretion in faeces and urines was higher on day 3 than on day 5. In June, the N excretion by the urine was lower than in September while the N excretion by the faeces was higher. Equations were calculated in order to estimate the N excretion by the urine in grazing dairy cows from the urea content in milk of a group of cows. [less ▲]

Detailed reference viewed: 24 (4 ULg)
Peer Reviewed
See detailInfluence of the frequency for the numerical modeling of the parasitic capacitances of wound magnetic components
De Greve, Zacharie; Lehti, Leena; Deblecker, Olivier et al

in 9th International Symposium on Electric and Magnetic Fields (EMF2013) (2013)

Detailed reference viewed: 8 (1 ULg)