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See detailEffects of exogenous gonadotropic and steroid hormones on the social behaviour and gonadal maturation of male domestic ducklings Anas platyrhynchos L.
Balthazart, Jacques ULg; Hendrick, J. C.

in Archives Internationales de Physiologie et de Biochimie (1979), 87(4), 741-61

Male domestic ducklings were injected during their first month of life with mammalian gonadotrophins (ovine LH or FSH, HMG) or gonadal steroids (testosterone or oestradiol). LH and testosterone stimulated ... [more ▼]

Male domestic ducklings were injected during their first month of life with mammalian gonadotrophins (ovine LH or FSH, HMG) or gonadal steroids (testosterone or oestradiol). LH and testosterone stimulated sexual behaviour while oestradiol inhibited the increase of aggression observed in control birds during the experiment. The mammalian gonadotrophins did not increase plasma testosterone but nevertheless they all stimulated the testis growth. Several hypotheses which could explain this finding (stimulation of spermatogenesis without any apparent effect on testosterone) are discussed and the possibility of a direct action of LH on the sexual behaviour is analysed. Social displays were only moderately stimulated by testosterone and not at all by gonadotrophins. The hormonal controls of these behaviour patterns remains thus largely unknown. [less ▲]

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See detailEffects of exogenous IL-1 beta, TNF alpha, IL-6, IL-8 and LIF on cytokine production by human articular chondrocytes.
Henrotin, Yves ULg; De Groote, D. D.; Labasse, A. H. et al

in Osteoarthritis and Cartilage (1996), 4(3), 163-73

Cytokines are potent regulators of the chondrocyte functions. Some of them are produced by chondrocytes and interact to regulate cartilage metabolism. In this study, we investigated the production of ... [more ▼]

Cytokines are potent regulators of the chondrocyte functions. Some of them are produced by chondrocytes and interact to regulate cartilage metabolism. In this study, we investigated the production of interleukin-1 beta (IL-1 beta), IL-6, IL-8 and leukemia inhibitory factor (LIF) by human chondrocytes and examined the modulation of their secretion by exogenous cytokines. Human articular chondrocytes were isolated from their extracellular matrix by a triple successive enzymatic digestion of the cartilage. Subsequently, chondrocytes were stimulated by increased amounts of human recombinant cytokines [IL-1 beta, tumour necrosis factor alpha (TNF alpha), IL-8, LIF, IL-6]. IL-1 beta, IL-6, IL-8 and LIF were assayed into culture media and inside cell extracts by specific enzyme amplified sensitivity immunoassays (EASIAs). Under these experimental conditions, we have identified various interactions between cytokines. IL-beta and TNF alpha highly stimulated IL-6, LIF and IL-8 productions. IL-6 decreased IL-8 synthesis and increased LIF production. IL-8 slightly enhanced IL-6 production. Finally, LIF stimulated IL-1 beta, IL-6 and IL-8 productions. Using neutralizing antibodies against IL-1, we demonstrated that the effects of LIF were secondary to the stimulation by LIF of IL-1 beta production by the chondrocytes. In conclusion, chondrocytes secrete a variety of immunocompetent cytokines including IL-1 beta, IL-6, IL-8 and LIF that can interact to regulate chondrocytes metabolism. These results also define new biological activities of LIF and IL-6, and raise questions concerning their role in the pathogenesis of joint diseases. [less ▲]

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See detailEffects of exotic invasive plants on soil properties in Belgium
Chapuis-Lardy, L.; Vanderhoeven, Sonia ULg; Dassonville, N. et al

Poster (2004)

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See detailEffects of experimental parameters on elemental analysis of coal by laser-induced breakdown spectroscopy
Li, Jie ULg; Lu, Jidong; Lin, Zhaoxiang et al

in Optics & Laser Technology (2009), 41(8), 907-913

The purpose of this work is to improve the precision of the elemental analysis of coal using laser-induced breakdown spectroscopy (LIBS). The LIBS technique has the ability to allow simultaneous elemental ... [more ▼]

The purpose of this work is to improve the precision of the elemental analysis of coal using laser-induced breakdown spectroscopy (LIBS). The LIBS technique has the ability to allow simultaneous elemental analysis and on-line determination, so it could be used in the elemental analysis of coal. Organic components such as C, H, O, N and inorganic components such as Ca, Mg, Fe, Al, Si, Ti, Na, and K of coal have been identified. The precision of the LIBS technique depends strongly on the experimental conditions, and the choice of experimental parameters should be aimed at optimizing the repeatability of the measurements. The dependences of the relative standard deviation (RSD) of the LIBS measurements on the experimental parameters including the sample preparation parameters, lens-to-sample distance, sample operation mode, and ambient gas have been investigated. The results indicate that the precision of LIBS measurements for the coal sample can be improved by using the optimum experimental parameters. [less ▲]

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See detailEffects of exposure to cadmium on calcium metabolism : a population study
Staessen, Jan; Amery, Antoon; Bernard, Alfred et al

in British Journal of Industrial Medicine (1991), 48

The objective was to investigate the hypothesis that environmental exposure to cadmium may affect calcium metabolism in the population at large. The 1987 participants (965 men and 1022 women), from 20 to ... [more ▼]

The objective was to investigate the hypothesis that environmental exposure to cadmium may affect calcium metabolism in the population at large. The 1987 participants (965 men and 1022 women), from 20 to 80 years old, constituted a random sample of the population of four Belgian districts. The urinary excretion of cadmium, a mesure of lifetime exposure, averaged 9.3 nmo/24h in men (range 0.4-324 nmol/24h) and 7.1 nmol/24h (range 0.1-71 nmol/24h) in women. Serum alkaline phosphatase activity and the urinary excretion of calcium correlated significantly and positively with urinary cadmium excretion in both men and women, and serum total calcium concentration negatively with urinary cadmium excretion in men only. The regression coefficients obtained after adjustment for significant covariates indicated that when urinary cadmium excretion increased twofold, serum alkaline phosphatase activity and urinary calcim excretion rose by 3-4% and 0.25 mmol/24h respectively, whereas in men serum total calcium concentration fell by 6 µmol/l. After adjustment for significant covariates the relation between serum total calcium concentration and urinary cadmium excretion was not significant in women. The findings suggest that even at environmental exposure levels calcium metabolism is gadually affected, as cadmium accumulates in the body. The morbidity associated with this phenomenon in industrialised countries remains presently unknown and requires further investigation. [less ▲]

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See detailEffects of extra-mixing processes on the periods of high-order gravity modes in main-sequence stars
Miglio, Andrea ULg; Montalban Iglesias, Josefa ULg; Noels-Grötsch, Arlette ULg

in Communications in Asteroseismology (2006), 147

In main-sequence stars, the chemical composition gradient that develops at the edge of the convective core is responsible for a non-uniform period spacing of high-order gravity modes. In this work we ... [more ▼]

In main-sequence stars, the chemical composition gradient that develops at the edge of the convective core is responsible for a non-uniform period spacing of high-order gravity modes. In this work we investigate, in the case of a 1.6 M(solar) star, the effects on the period-spacing of extra mixing processes in the core (such as diffusion and overshooting). [less ▲]

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See detailEffects of extraction solvents on phenolic contents and antioxidant activities of Tunisian date varieties (Phoenix dactylifera L.)
Kchaou, W; Abbès, F; Blecker, Christophe ULg et al

in Industrial Crops & Products (2013), 45

Second-grade dates (Phoenix dactylifera L.), with hard texture, from six Tunisian cultivars were analysed for their composition and antioxidant activities. Results showed predominance of total sugars and ... [more ▼]

Second-grade dates (Phoenix dactylifera L.), with hard texture, from six Tunisian cultivars were analysed for their composition and antioxidant activities. Results showed predominance of total sugars and a relatively low content of protein, fat andash. On the other hand, optimisation of extraction of antioxidant was carried using five different solvents. The highest level of phenolic compounds for all dates varieties was found in the 70% acetone extract. This level ranged from 199.43 to 576.48 mg of GAE/100 g fresh weight. However, extraction into 50% methanol gave the highest antioxidant activity from 89.55 to 109.67 mg equivalents of ascorbic acid/g fresh weight. For both two olvents, Bejo exhibited the highest phenolic content and total antioxidant activity, while Baydh El Hamam presented the owest. A positive linear correlation between total antioxidant activity and phenolic contents was observed (R2 = 0.83; R2 = 74 for acetone/H2O and methanol/H2O, respectively). The antioxidant activity of acetone/H2O and methanol/H2O extracts was carried using DPPH radical-scavenging activity and reducing power. These results showed that dates had strongly scavenging activity on DPPH reaching 90.12% in methanol/H2O from Deglet Nour. Whereas, acetone/H2O showed the best reducing power which Bejo was significantly higher than the other varieties. This study demonstrates the potential antioxidant activity with Tunisian date, that we can use these natural extracts as food additives in replacement of synthetic compounds. [less ▲]

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See detailEffects of extreme meteorological conditions on coastal dynamics near a submarine canyon
Skliris, Nikolaos ULg; Lacroix, Geneviève; Djenidi, Salim ULg

in Continental Shelf Research (2004), 24(9), 1033-1045

A 3-D hydrodynamic model is applied to assess shelf/slope exchanges in the Calvi Canyon region (Corsica, NW Mediterranean) during the violent storm that affected the Western Europe in December 1999 ... [more ▼]

A 3-D hydrodynamic model is applied to assess shelf/slope exchanges in the Calvi Canyon region (Corsica, NW Mediterranean) during the violent storm that affected the Western Europe in December 1999. Simulations are carried out using high-frequency sampling meteorological data to take into account the short-term variability of the atmospheric conditions. It is shown that the combined effects of canyon topography and of the wind forcing during the storm are responsible for a large increase of both cross-shore and vertical transports in the area. Strong downwelling motion is simulated all along the continental slope with vertical velocities up to 2cm s(-1) within the canyon. High turbulent diffusion levels are obtained leading to the complete mixing of the water column within the canyon. Results suggest that increased turbulent diffusion and downwelling circulation in the canyon during the storm should result in a large transport of coastal water towards the abyssal plain. (C) 2004 Elsevier Ltd. All rights reserved. [less ▲]

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See detailEffects of extremely low frequency electromagnetic fields (ELF) on human beings
Lilien, Jean-Louis ULg; Dular, Patrick ULg; V Sabariego, Ruth ULg et al

in International Colloquium on Power frequency electromagnetic fields ELF EMF, Sarajevo, Bosnia and Herzegovina (2009)

A rough overview of typical values of ELF fields will be presented followed by a brief literature survey on childhood leukaemia and ELF. The potential carcinogenic effect of ELF would be linked to ... [more ▼]

A rough overview of typical values of ELF fields will be presented followed by a brief literature survey on childhood leukaemia and ELF. The potential carcinogenic effect of ELF would be linked to electrical disturbances in cell behaviour. The major concern linking childhood leukaemia and ELF is thus to determine the response of bone marrow cells under ELF fields. With that purpose, transmembrane potential will be targeted and linked to the E-field at that level. [less ▲]

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See detailEffects of extremely low frequency electromagnétic fields (ELF) on human beings. An electrical engineer viewpoint.
Lilien, Jean-Louis ULg; Dular, Patrick ULg; V Sabariego, Ruth ULg et al

in Revue d'électricité et d'électronique industrielle - tijdschrift voor elektriciteit en industriele elektronika (2008), 3

Since the early seventies, potential health risks from Extremely Low Frequency (ELF) exposure (50 Hz) have been extensively treated in the literature (more than 1000 references registered by WHO1, 2007 ... [more ▼]

Since the early seventies, potential health risks from Extremely Low Frequency (ELF) exposure (50 Hz) have been extensively treated in the literature (more than 1000 references registered by WHO1, 2007). After 30 years of worldwide research, the major epidemiological output is the possible moderate increased risk (by a factor 2) of childhood leukaemia in case of a long exposure to an ambient magnetic flux density (B-field) higher than 0.4 μT. However, this fact has not been confirmed by in vivo and/or in vitro studies. Moreover it has not been validated by any adverse health biological mechanisms neither for adults nor for children. Nobody knows precisely what happens inside the body and what could be a hazardous health effect of the ELF fields at 50 Hz. International recommendations (ICNIRP2) are currently, for general public, not to exceed a B-field of 100 μT (50 Hz) and an E-field of 5 kV/m (50 Hz). The authors are looking for a signal generated in the biological process under electric interactions. Herein, a rough overview of typical values of ELF fields will be presented followed by a brief literature survey on childhood leukaemia and ELF. The potential carcinogenic effect of ELF would be linked to electrical disturbances in cell behaviour. The major concern linking childhood leukaemia and ELF is thus to determine the response of bone marrow cells under ELF fields.With that purpose, transmembrane potential will be targeted and linked to the E-field at that level. This paper is three-folded: First, the electric interactions between ambient ELF fields and the body are studied both qualitatively and quantitatively. Though no adverse health field threshold is defined, a minimum field level is fixed in order to discriminate inherent random noise, in agreement with NIEHS3. This is based on the fact that mechanisms become only plausible under field exposure above a certain strength. Different sources of internal E-field are analysed and classified according to their potential risk. Second, the hypothesis of contact current is detailed. Finally, key actions to undertake are highlighted. Based on the current state of the art and some authors’ own developments, this paper proposes simple low cost modifications of private electrical installations in order to annihilate the major source of potential effects of ELF. Particular emphasis is paid to the situation in Belgium as the authors are part of the BBEMG (see end note) and perform numerous measurements in Belgian residential homes. [less ▲]

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See detailEffects of eythropoietin administration on mitral regurgitation and left ventricular remodeling in heart failure patients.
Cosyns, B.; Velez-Roa, S.; Droogmans, S. et al

in International Journal of Cardiology (2010), 138(3), 306-307

The effects of erythropoietin administration on mitral regurgitation in patients with congestive heart failure have not yet been examined. After 2 months, erythropoietin treatment results in a significant ... [more ▼]

The effects of erythropoietin administration on mitral regurgitation in patients with congestive heart failure have not yet been examined. After 2 months, erythropoietin treatment results in a significant reduction in left ventricular volumes and mitral regurgitation severity and improves hemodynamics. [less ▲]

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See detailEffects of Fabaceae cover on soil parameters and analysis of environmental determinants of floristic variability in North-Eastern Ruvubu, Burundi
Masharabu, T.; Noret, N.; Bigendako, M. J. et al

in International Journal of Current Trends in Science and Technology (2011), 2(2), 113-124

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See detailEffects of face and voice learning on access to semantic information from names.
Barsics, Catherine ULg

in Perception (2010), 39 supplement

Several studies showed that it is more difficult to retrieve semantic information from recognized voices than from recognized faces. However, earlier studies that investigated the recall of biographical ... [more ▼]

Several studies showed that it is more difficult to retrieve semantic information from recognized voices than from recognized faces. However, earlier studies that investigated the recall of biographical information following person recognition used stimuli that were pre-experimentally familiar to the participants, such as famous people’s voices and faces. The present study was designed in order to allow a stricter control of frequency exposure with both types of stimuli (voices and faces) and to ensure the absence of identity cues in the spoken extracts. In the present study, subjects had to associate lexical (i.e., name) and semantic information (i.e., occupation) with faces or voices. Interestingly, when asked later to recall semantic information being cued by the person’s names, participants provided significantly more occupations for the targets that had been previously associated with faces than with voices. Moreover, participants’ performance was not significantly different when names and occupation were associated with voices compared with dog’s faces, whose complexity is similar to that of human faces, but for which we have poorer discrimination abilities. These results and their implications for person recognition models, as well as the potential role of the relative distinctiveness of faces and voices, are discussed. [less ▲]

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See detailEffects of feed supplementation with specific hen egg yolk antibody (immunoglobin Y) on Salmonella species cecal colonization and growth performances of challenged broiler chickens
Chalghoumi, Raja; Marcq, Christopher ULg; Thewis, André ULg et al

in Poultry Science (2009), 88(10), 2081-2092

Anti-Salmonella spp. egg yolk antibodies (IgY) simultaneously directed against Salmonella Enteritidis and Salmonella Typhimurium were tested to determine if their inclusion in feed decreased Salmonella ... [more ▼]

Anti-Salmonella spp. egg yolk antibodies (IgY) simultaneously directed against Salmonella Enteritidis and Salmonella Typhimurium were tested to determine if their inclusion in feed decreased Salmonella spp. cecal colonization in experimentally infected broiler chickens. Egg yolk powder (EYP) was obtained by freeze-drying egg yolks containing anti-Salmonella spp. Immunoglobin Y was included in feed at 5 levels of concentration (0 to 5%). Feeds were formulated to similar nutrient levels and provided for ad libitum intake from d 1 to 28. Three days after initiation of feed treatments (d 4), chickens were co-challenged with equal numbers of Salmonella Enteritidis and Salmonella Typhimurium (2x10(6) cfu/bird). Cecal samples were recovered weekly over the experimental period (d 7 to 28) to enumerate Salmonella spp. The effect of anti-Salmonella spp. IgY feed supplementation on growth performance of infected chickens was also evaluated during the same period. In comparison with the positive control treatment (PC), treatments involving EYP (T1, T2, T3, T4, and T5), whether containing anti-Salmonella spp. IgY or not, significantly improved (P<0.05) the growth performance of challenged chickens, but without reaching the performance levels of nonchallenged chickens (NC1 and NC2). However, no link can be established between the enhancement in growth performance of challenged birds and their contamination levels by Salmonella because in-feed incorporation of EYP had no significant effect on cecal colonization by Salmonella. Furthermore, the comparison of the 5 anti-Salmonella spp. IgY concentration levels in feed did not reveal any anti-Salmonella spp. IgY concentration effect on growth performance and Salmonella cecal colonization. These results suggest that anti-Salmonella spp. IgY would undergo denaturation and degradation after their passage through the animal gastrointestinal tract and reveal that components of EYP other than specific antibodies have a beneficial effect on growth performance. [less ▲]

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See detailEffects of feeding frequency on water intake in cats
Kirschvink, N.; Lhoest, E.; Leemans, J. et al

in Journal of Veterinary Internal Medicine (2005, May)

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See detailEffects of FeSO4 on B16 melanoma cells differentiation and proliferation
Gillet, Marie-Claire ULg; Siwek, Brigitte; Pozzi, G. et al

in Anticancer Research (1990), 10(4), 1029-1033

The paper shows that FeS04 can increase or reduce B16 cell proliferation and melanogenesis. Vitamin C toxicity for B16 cells was reduced in the presence of FeSO4.

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See detailEffects of fetal bovine serum, FSH and 17ß-Estradiol on the culture of bovine preantral follicles
Hulshof, S. C. J.; Figueiredo, J. R.; Beckers, Jean-François ULg et al

in Theriogenology (1995), 44(2), 217-226

We describe a 7-d culture in droplets of collagen gel of isolated small bovine preantral follicles in medium with or without 10% fetal bovine serum (FBS). In addition, the effect of human recombinant FSH ... [more ▼]

We describe a 7-d culture in droplets of collagen gel of isolated small bovine preantral follicles in medium with or without 10% fetal bovine serum (FBS). In addition, the effect of human recombinant FSH and 17beta-estradiol on the morphology and growth of the preantral follicles was investigated in medium without FBS. After culture in medium with 10% FBS, the increase in follicle diameter was 13.1 +/- 8.4 microm, the percentage of BrdU-labeled cells was 49.9 +/- 11.3 and the number of cells per area granulosa was 11.1 +/- 1.8. Omission of serum from the culture medium had no effect on the percentage of labeled cells, but the diameter increase was lower and the cells were smaller. Apparently, serum affects the size of the granulosa cells from small preantral follicles rather than the stimulation of cell proliferation. Addition of human recombinant FSH and/or 17beta-estradiol to serum-free medium resulted in a larger diameter increase during culture compared with that of the control. With FSH, this was due to an increase in cell proliferation, while with estradiol this was caused by an increase in granulosa cell size. The effects of simultaneous treatment with FSH and estradiol was simply the combination of their individual effects. In conclusion, small bovine preantral follicles can be cultured for 7 d in the absence of serum and hormones. The follicles increase in diameter and react to FSH with enhanced cell proliferation and to estradiol with an increase in cell size. [less ▲]

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