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See detailEffect of the kinematic hardening in the simulations of the straightening of long rolled profiles
Bouffioux, Chantal ULiege; Boman, Romain ULiege; Caillet, Nicolas et al

in Key Engineering Materials [=KEM] (2014), 611-612

Residual stresses and lack of straightness appear during the cooling of sheet piles where the initial temperature field is not homogeneous. To meet the standards, the long hot rolled pieces are ... [more ▼]

Residual stresses and lack of straightness appear during the cooling of sheet piles where the initial temperature field is not homogeneous. To meet the standards, the long hot rolled pieces are straightened using a series of rollers placed alternately above and below the pieces with shifts which create a succession of bendings. The process is modeled to study the impact of the industrial parameters ( the duration of the cooling and the rollers positions), to improve the final geometry and to reduce the residual stresses.Tests are carried out on this structural steel to observe the material behavior, then material laws are chosen and parameters of these laws are defined using and inverse method. Two sets of material data are obtained: for the first one, the hardening is supposed to be isotropic, and for the second one, additional tests are performed to describe isotropic and kinematic hardenings.The cooling followed by the straightening is then simulated by the finite element with these two sets of date. The comparison of the rollers forces, the deformation and the residual stresses show the impact of the kinematic hardening on such a process where the material undergoes a sucession of the tensions and compressions. The real forces applied by the rollers,the real curvature of the interlocks at the end of the straightening process and the distribution of the residual longitudinal stresses measured on the web using the ring core method are used to validate the numerical model. [less ▲]

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See detailEffect of the lengthening of the protocol on the reliability of knee muscle fatigue indicators
Bosquet, L.; Maquet, Didier ULiege; Forthomme, Bénédicte ULiege et al

in European Journal of Sports Medicine (2013, September), 1(1), 150

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See detailEffect of the Lengthening of the Protocol on the Reliability of Muscle Fatigue Indicators
Bosquet, Laurent; Maquet, Didier ULiege; Forthomme, Bénédicte ULiege et al

in International Journal of Sports Medicine (2010), 31(2), 82-88

The aim of this study was to examine absolute and relative reliability of fatigue measures calculated from peak torque or total work during 20, 30, 40 and 50 reciprocal maximal concentric contractions ... [more ▼]

The aim of this study was to examine absolute and relative reliability of fatigue measures calculated from peak torque or total work during 20, 30, 40 and 50 reciprocal maximal concentric contractions performed on an isokinetic dynamometer at 180 ° · s " 1 . Eighteen moderately active men performed 50 reciprocal maximal concentric contractions on three occasions with one 7 – 10 days recovery between each session. Peak torque and total work were computed for each contraction and subsequently summed to compute cumulated performance after respectively 20, 30, 40 and 50 repetitions. Muscle fatigue was determined after 20, 30, 40 and 50 repetitions by the fatigue index, the percent decrease in performance and the slope. Reliability of average peak torque or average total work was similar and was not a! ected by the lengthening of the protocol, although a learning e! ect was evident for knee flexors. Reliability of fatigue measures calculated from peak torque or total work was similar, improved with the lengthening of the protocol and was better for knee extensors. Measuring average peak torque or average total work and the slope during a protocol involving 30 maximal reciprocal concentric contractions appear to represent a better compromise between reliability and physiological interpretability of the data. [less ▲]

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See detailEffect of the luteinizing hormone on embryo production in superovulated rabbit does
Salvetti, P.; Theau-Clement, M.; Beckers, Jean-François ULiege et al

in Theriogenology (2007), 67(6), 1185-1193

For most domestic animals, the responses to superovulation treatments are not controlled as a consequence of the lack of knowledge on exogenous gonadotrophins effects on the ovarian function. The role of ... [more ▼]

For most domestic animals, the responses to superovulation treatments are not controlled as a consequence of the lack of knowledge on exogenous gonadotrophins effects on the ovarian function. The role of luteinizing hormone (LH) on the number and quality of embryos produced was evaluated on rabbit does superovulated with porcine FSH (pFSH). Parameters of embryos recovery, in vitro and in vivo embryo development rates after freezing/thawing were compared. We used three experimental groups: (1) control group without superovulation treatment, (2) "pFSH + pLH" and (3) "pFSH" groups where females were treated with pFSH, respectively, with (20%) or without (0%) porcine LH supplementation. The number of corpora lutea and the number of embryos produced were significantly higher (p < 0.001) in superovulated does than in control group (27.1, 26.7 versus 11.9 corpora lutea and 20.3, 21.2 versus 9.6 embryos produced for pFSH + pLH, pFSH and control group, respectively). However, both gonadotrophins administrations (groups 2 and 3) led to defaults of ovulation when compared with untreated does. No significant difference was observed between the number and quality of the embryos produced by does treated with pFSH + pLH or with pFSH alone. Moreover, we observed no significant difference between results of in vivo and in vitro viability assays after thawing. We concluded that pFSH alone seems to be sufficient to stimulate the follicles growth and that exogenous pLH administrated has no effect on the quantity and quality of embryos. Further studies are needed to evaluate the hormonal patterns before and after the gonadotrophins injections in the rabbit species. (c) 2007 Elsevier Inc. All rights reserved. [less ▲]

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See detailThe effect of the mechanical and structural properties of steel at elevated temperatures on the buckling of fire exposed columns
Franssen, Jean-Marc ULiege; Janss, José; Twilt, Leen

Report (1988)

Among other things, this reports explains how residual stresses have to be modelled in the numerical simulation of a structure subjected to fire

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See detailThe effect of the mesoporosity on the crystalline growth of hematite films used as photoelectrodes in water splitting
Toussaint, Caroline ULiege; Cloots, Rudi ULiege; Henrist, Catherine ULiege

Poster (2013)

The environmental effect of atmospheric CO2 associated with other geopolitical and economic problems linked to fossil fuels have urged the research and the development of new and clean sources of energy ... [more ▼]

The environmental effect of atmospheric CO2 associated with other geopolitical and economic problems linked to fossil fuels have urged the research and the development of new and clean sources of energy. The photoelectrolysis of water is an interesting way to produce clean fuel by converting solar energy into hydrogen. Hematite is a particularly attractive material for the photoelectrolysis of water thanks to its abundance, high stability in water and absorption in the visible part of the solar spectrum. Furthermore, the position of its valence band affords the oxidation of water into O2. Nevertheless, hematite has some drawbacks like a too low conduction band to reduce water, a bad conduction of electrons and a very short diffusion length of holes (2-10 nm). The application of a bias resolves the positioning of the conduction band, while the conduction of electrons is improved by adding a dopant (SiO2 or TiO2). The short diffusion length, for its part, is improved by reducing the distance electrode-electrolyte. For this purpose, we developed mesoporous hematite films doped by TiO2 by spin coating, based on the EIMP principle (Evaporation Inducing Micelles Packing). For the sake of comparison, a non mesoporous film was prepared. The crystallinity, the mesostructure and the performance in water splitting of the films were then characterized. Due to the high temperature of crystallization of the hematite, we had to proceed to the fine tuning of the thermal treatment to obtain a crystallized film and to preserve its mesoporosity, which was confirmed by TEM. Based on XRD analysis, it comes out that the mesoporosity leads to smaller grains than without mesoporosity. The water splitting performances were evaluated by measuring the photocurrent density under illumination (AM 1.5G, 100mW/cm²) and the mesoporous film showed promising efficiencies (1.9mA/cm²). [less ▲]

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See detailEffect of the method and the period of oil extraction on chemical composition of olive cake in northern of Morocco
El Otmani, Samira ULiege; Ayadi, Mohamed; Chentouf, Mouad et al

in Bayrou, Calixte; Cabaraux, Jean-François; Delguste, Catherine (Eds.) et al Proceedings of the 3rd FARAH Day (2016)

In the northern of Morocco, goat population is the most dominant. His diet is based on forest rangelands. Therefore, it is necessary to diversify and improve its feed calendar. Olive cake is by-product of ... [more ▼]

In the northern of Morocco, goat population is the most dominant. His diet is based on forest rangelands. Therefore, it is necessary to diversify and improve its feed calendar. Olive cake is by-product of oil extraction that widely available in the region with important production. It can be a feed resource of ruminant. This resource is produced by three methods and for limited period. This work aims to determine the effect of different oil extraction method and period on the chemical composition of olive cake in northern of Morocco. Twenty-seven samples of olive cake were collected from 3 mills by each extraction method (mechanical pressure, centrifugation 2 and 3 phases) during three periods (November, December and January). The chemical composition (dry matter, fat, mineral matter, crude protein and fibers) of the collected samples was determined by AOAC methods (1997). The extraction method had a significant effect on all parameters of the chemical composition with the exception of the fat and crude protein (P<0.05). The olive cake obtained by centrifugation 2 phases method had lower dry matter and fibers. The period had no effect on chemical composition, which eases the introduction of olive cake in the diet of ruminants. The olive cake of 2 phases is the most suitable for feed but has a reduced shelf life, which requires the development of a suitable conservation mode. [less ▲]

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See detailEffect of the milk recording time on the genetic parameters of milk production and mid-infrared milk components in Luxembourg dairy cattle
Arnould, Valérie ULiege; Gengler, Nicolas ULiege; Soyeurt, Hélène ULiege

in Journal of Dairy Science (2012, July), 95

A particularity of the Luxembourg milk recording is the use of different schemes. Two principal schemes are applied: the scheme “S” applied on 69.1% of the total herds (n=712) and consisting in one ... [more ▼]

A particularity of the Luxembourg milk recording is the use of different schemes. Two principal schemes are applied: the scheme “S” applied on 69.1% of the total herds (n=712) and consisting in one proportionate sample of all daily milkings, and the scheme “T” (21.6% of the total herds) which consists in one sample of only one milking (morning or evening milking) (and alternating milking time from month to month). The problematic is that application of different schemes could influence the milk components (protein and fat yield) and the milk fat components (saturated and unsaturated groups of fatty acids) genetic parameters estimation and to prevent all comparisons between dairy population under different milk recording schemes. A total of 47,613 and 44,833 test-day records were obtained, respectively for schemes “S” and “T” from Holstein cows in first lactation in Luxembourg dairy herds. The used model included as fixed effects: herd x date of test, class of age, and month x year. Random effects were permanent environmental, additive genetics, and residual effects. The main objective of this work is to study the effect the choice of milk recording schemes (“S” or “T” schemes) on milk yield and milk components genetic parameters. A solution could be to add a fixed effect taking in account the milking time. The second objective is to study the effect of milking time (morning or evening) on genetic parameters estimated in the case of scheme “T”. According to the results, genetic parameters were statistically different between the schemes “S” and “T” for milk yield (P value < 0.0001). Further, the classifications of bulls according to their breeding values were very different when values were estimated on basis of scheme “S” or “T” (Spearman correlation value of 0.51 for milk yield for example). In conclusion, using several milk recording schemes do not allow any comparison of genetic parameters between dairy cattle’s. [less ▲]

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See detailEffect of the msb3 msb4 double mutation on the intracellular pool of purine nucleotides in the yeast Saccharomyces cerevisiae: application to the study of the biological activity of the oncogenic human protein oncTre210p.
Bach, Stéphane; Burny, Arsène; Bontemps, Françoise et al

in Yeast (Chichester, England) (2001), 18(S305), 17-7

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See detailEffect of the nature of the single-isomer anionic CD and the BGE composition on the enantiomeric separation of beta-blockers in NACE.
Rousseau, Anne ULiege; Chiap, Patrice ULiege; Oprean, Radu et al

in Electrophoresis (2009), 30(16), 2862-8

The separation of ten beta-blockers has been investigated in NACE systems using heptakis(2,3-di-O-methyl-6-O-sulfo)-beta-CD (HDMS-beta-CD) and heptakis(2,3-di-O-acetyl-6-O-sulfo)-beta-CD (HDAS-beta-CD ... [more ▼]

The separation of ten beta-blockers has been investigated in NACE systems using heptakis(2,3-di-O-methyl-6-O-sulfo)-beta-CD (HDMS-beta-CD) and heptakis(2,3-di-O-acetyl-6-O-sulfo)-beta-CD (HDAS-beta-CD). The influence on enantioresolution, mobility difference and selectivity of the nature of both anionic CD and BGE anion as well as their concentrations were studied by means of a multivariate approach. A D-optimal design with 25 experimental points was applied. For all studied analytes, the enantiomeric resolution was shown to be significantly influenced by both CD nature and concentration. Except for two compounds, HDAS-beta-CD was found to give higher enantioresolution values than HDMS-beta-CD. The best enantioseparation for all compounds was achieved in the presence of a high chiral selector concentration and for most of them at a low BGE anion concentration. For each investigated compound, operating conditions leading to the best enantiomeric resolution were deduced. A generic NACE system was then recommended, namely 10 mM ammonium acetate and 40 mM HDAS-beta-CD in methanol acidified with 0.75 M formic acid. This generic system was able to completely resolve the enantiomers of all beta-blockers, with a R(s) value of at least 4. Finally, the optimal conditions obtained modelling resolution, mobility difference and selectivity were compared. [less ▲]

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See detailEffect of the number of subcultures on anatomical and biochemical characteristics of micropropagated strawberry shoots, in relation to their abnormal flowering.
Jemmali, A.; Boxus, P.; Kevers, Claire ULiege et al

in Mededelingen van de Faculteit Landbouwkundige en Toegepaste Biologische Wetenschappen (Rijksuniversiteit te Gent) (1995), 60(3b),

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See detailEffect of the presence of females on the pituitary-testicular activity in male Japanese quail (Coturnix coturnix japonica).
Delville, Y.; Sulon, J.; Hendrick, J. C. et al

in General and Comparative Endocrinology (1984), 55(2), 295-305

Five experiments were carried out to study the role of the presence of a female on the reproductive endocrinology of male Japanese quail. In the first three experiments, exposure of an adult male raised ... [more ▼]

Five experiments were carried out to study the role of the presence of a female on the reproductive endocrinology of male Japanese quail. In the first three experiments, exposure of an adult male raised in long days to a female for l0 min or l week failed to increase plasma testosterone and LH levels; in fact a significant transitory decrease in plasma testosterone was observed, associated with a preceding increase in plasma corticosterone. These changes are interpreted as a result of the stress caused by repeated bleeding or by the continuous presence of a female in a limited space. In the last two experiments, an increase in the maturation rate of immature males could be observed in birds maintained in the continuous presence of females by comparison with birds kept in isolation. The paired males had larger cloacal glands and testes and higher plasma levels of testosterone and LH than the isolated one. This effect of the female was observed in long days (l6L:8D) as well as in marginally stimulating short days (l2L:l2D). [less ▲]

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See detailThe effect of the protein level in a pre-starter diet on the post-hatch performance and activation of ribosomal protein S6 kinase in muscle of neonatal broilers.
Everaert, Nadia ULiege; Swennen, Quirine; Coustard, Sonia Metayer et al

in The British journal of nutrition (2010), 103(2), 206-11

The cytoplasmic serine/threonine ribosomal protein S6 kinase (S6K1) plays a critical role in controlling protein translation. There is evidence that amino acids regulate S6K1 and protein synthesis in ... [more ▼]

The cytoplasmic serine/threonine ribosomal protein S6 kinase (S6K1) plays a critical role in controlling protein translation. There is evidence that amino acids regulate S6K1 and protein synthesis in avian species, but the effect of dietary protein level on the activation of S6K1 in neonatal chicks is unknown. Therefore, the aim of the present experiment was to investigate the effect of different protein levels, supplied during the first 5 d post-hatch, on body growth, breast muscle development and on the activation of S6K1 and its downstream target, the S6, in neonatal chicks. Chicks were fed a pre-starter diet during the first 5 d post-hatch containing low (19.6 % crude protein (CP); LP), medium (23.1 % CP; MP) or high (26.7 % CP) levels (HP) of protein. Weight gain of chicks fed the HP diet was higher (P < 0.05) compared with those fed the LP diet during day (d)3-d5 and the numerical advantage of this group was maintained from d2 to d7. On d2 and d3, greater levels of S6K1 and S6 phosphorylation and/or activity were observed in chicks receiving the HP diet compared with LP and MP diets, without differences between results of the latter two dietary treatments. In conclusion, the present results suggest that early protein nutrition impacts the development of broiler chicks. [less ▲]

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See detailEffect of the ratio of dietary n-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid on broiler breeder performance, egg quality, and yolk fatty acid composition at different breeder ages.
Koppenol, A.; Delezie, E.; Aerts, J. et al

in Poultry science (2014), 93(3), 564-73

When added to the feed of broiler breeder hens, dietary polyunsaturated fatty acids (FA) can be incorporated into the yolk and therefore become available to the progeny during their early development. The ... [more ▼]

When added to the feed of broiler breeder hens, dietary polyunsaturated fatty acids (FA) can be incorporated into the yolk and therefore become available to the progeny during their early development. The mechanism involved in lipid metabolism and deposition in the egg may be influenced by breeder age. Before the effect of an elevated concentration of certain polyunsaturated FA on the embryo can be investigated, the effect at breeder level and egg quality must be further assessed. The aim of the present experiment was to evaluate the effects of dietary n-6/n-3 ratios and dietary eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) ratios, provided to broiler breeder hens, in terms of their zoo technical performance, egg quality, and yolk FA composition. Starting at 6 wk of age, 640 Ross-308 broiler breeder hens were fed 1 of 4 different diets. The control diet was a basal diet, rich in n-6 FA. The 3 other diets were enriched in n-3 FA, formulated to obtain a different EPA/DHA ratio of 1/1 (EPA = DHA), 1/2 (DHA), or 2/1 (EPA). In fact, after analysis the EPA/DHA ratio was 0.8, 0.4, or 2.1, respectively. Dietary EPA and DHA addition did not affect the performance of the breeder hens, except for egg weight. Egg weight was lower (P < 0.001) for all n-3 treatments. Dietary EPA improved number of eggs laid in the first 2 wk of the production cycle (P = 0.029). The absolute and relative yolk weight of eggs laid by EPA = DHA fed hens was lowest (P = 0.004 and P = 0.025, respectively). The EPA and DHA concentrations in the yolk were highly dependent on dietary EPA and DHA concentrations with a regression coefficient equal to 0.89. It can be concluded that dietary EPA and DHA can be incorporated in the breeder egg yolk to become available for the developing embryo, without compromising the performance and egg quality of the flock. [less ▲]

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