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See detailDetermination of polyisoprene-block-poly(methyl methacrylate) domain sizes using 1H spin diffusion
Werkhoven, Thekla M; Mulder, Fokko M; Zune, Catherine et al

in Macromolecular Chemistry and Physics (2003), 204(1), 46-51

The microphase structure of polyisoprene-block-poly(methyl methacrylate) diblock copolymers was studied using solid-state NMR techniques. Wideline separation spectroscopy reveals a narrow interphase ... [more ▼]

The microphase structure of polyisoprene-block-poly(methyl methacrylate) diblock copolymers was studied using solid-state NMR techniques. Wideline separation spectroscopy reveals a narrow interphase between the two polymers. The domain sizes of a lamellar sample and a sample with hexagonally ordered cylinders were determined using 1H spin diffusion. The lamellar sample shows a domain size of 16 ± 2 nm for the minor polyisoprene phase and a long period of 33 ± 4 nm. The cylindrical structure has a long period of 38 ± 7 nm, the diameter of the PMMA cylinders is 21 ± 4 nm. These results are about 20% below the estimates obtained from theoretical calculations according to Helfand and Wasserman [less ▲]

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See detailDetermination of porcine plasma follitropin levels during superovulation treatment in cows
Demoustier, M.; Beckers, Jean-François ULg; Van Der Zwalmen, P. et al

in Theriogenology (1988), 30(2), 379-386

Porcine follicle stimulating hormone (pFSH) and porcine luteinizing hormone (pLH), are widely used to induce superovulation in cows. An advantage of this treatment is that the LH:FSH ratio can be varied ... [more ▼]

Porcine follicle stimulating hormone (pFSH) and porcine luteinizing hormone (pLH), are widely used to induce superovulation in cows. An advantage of this treatment is that the LH:FSH ratio can be varied to optimize the growth of the ovarian follicles. However, due to the relatively short half-life of FSH, the superovulatory treatment requires numerous injections. A performant radioimmunoassay system (sensitivity=0.2 ng/ml plasma) was used to determine plasma pFSH levels in cows that were superovulated with 2 daily injections of 4 Armour Units (A.U.) of pFSH for 4 d. From plasma profiles, the half-life and the disappearance of pFSH were estimated at 5 h and at 10 to 12 h, respectively, confirming the necessity of using two daily injections. [less ▲]

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See detailDetermination of pregnancy-associated glycoprotein concentrations in goats (Capra hircus) with unsuccessful pregnancies: a retrospective study
Zarrouk, A.; Engeland, I.; Sulon, Joseph ULg et al

in Theriogenology (1999), 51(7), 1321-31

Presented here are the profiles of pregnancy-associated glycoprotein (PAG) concentrations in blood collected weekly from goats experiencing maintained and unsuccessful pregnancies. The analysis of these ... [more ▼]

Presented here are the profiles of pregnancy-associated glycoprotein (PAG) concentrations in blood collected weekly from goats experiencing maintained and unsuccessful pregnancies. The analysis of these profiles clearly indicated 4 different situations: the pseudopregnancy syndrome, abortion between Days 89 and 137, parturition of 1 dead and 1 live fetus, and expulsion of macerated or mummified fetuses after full term. A marked reduction in PAG concentration at any time during pregnancy was followed by an event such as abortion or the expulsion of a dead fetus at term or later. [less ▲]

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See detailDetermination of Pregnancy-Associated Glycoprotein concentrations in sheep: a retrospective study
Gajewski, Zdzislaw; Beckers, Jean-François ULg; Melo de Sousa, Noelita ULg et al

in Advances in Cell Biology (1999), 26(Supplement 12), 89-96

This study is carried out to determine ovine pregnancy associated glycoprotein (oPAG) levels in the serum of Berrichone ewes throughout gestation and the first month post partum. The levels were ... [more ▼]

This study is carried out to determine ovine pregnancy associated glycoprotein (oPAG) levels in the serum of Berrichone ewes throughout gestation and the first month post partum. The levels were determinated with heterologous RIA using bovine PAG as standard and tracer and rabbit antiserum against oPAG. The level of oPAG increased from the 4th week of pregnancy till 12-13th week and decreased slowly till 17th week, when increased rapidly and reached the highest level (around 600-700 ng/ml). In the sheep carrying twins, we observed higher levels of oPAG than in the uniparous sheep. After lambing, oPAG decreased rapidly in 4 week to basal values. The oPAG concentrations in the animals carrying twins was higher when comparised to single lamb. We concluded that the oPAG level depends on the number of lambs and term of pregnancy. The estimation of oPAG concentrations in the blood can be used as a indicator for pregnancy diagnosis. [less ▲]

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See detailDetermination of pregnancy-associated glycoprotein, P4, E1S and PgFM concentrations in the sheep during pregnancy
Gajewski, Z.; Beckers, Jean-François ULg; Thun, R.

in Proceedings: 23rd World Buiatrics Congress, Québec, Canada (2004)

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See detailDetermination of pregnancy-associated glycoproteins (bPAG) in cow’s milk
Metelo, R.; Silva, S.; Sulon, J. et al

in Proceedings: 23rd World Buiatrics Congress, Québec, Canada (2004)

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See detailDetermination of radiative lifetimes of neutral sulphur by time-resolved three-photon VUV laser spectroscopy
Berzinsh, U.; Caiyan, L.; Zerne, R. et al

in Physical Review. A : General Physics (1997), 55

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See detailDetermination of radiative lifetimes of neutral sulphur by time-resolved three-photon VUV laser spectroscopy
Li, Z. S.; Persson, A.; Svanberg, S. et al

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (1998), 2

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See detailDetermination of residue levels in juvenile rainbow trouts treated by 17 alpha-methyltestosterone for sex reversal
Gaspar, P.; Desmons, Pierre; Drot, S. et al

in Analysis of anabolizing and doping agents in biosamples (1990)

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See detailDetermination of Romanian alfalfa crude protein and crude fiber contents as well as in vitro organic matter digestibility by NIR spectrometry
Dale, Laura ULg; Thewis, André ULg; Rotar, Ioan et al

in Scientific Papers. Series D, Animal Science (2012, October 04)

Alfalfa (Medicago sativa L.) is a high quality forage which has been used worldwide. The superiority of alfalfa lies in its high yield, high protein content and high digestibility. The aim of this study ... [more ▼]

Alfalfa (Medicago sativa L.) is a high quality forage which has been used worldwide. The superiority of alfalfa lies in its high yield, high protein content and high digestibility. The aim of this study was to develop a simple, fast and non-destructive method, named Near Infrared Spectroscopy (NIRS) to determinate alfalfa quality. To realize this study, alfalfa samples were obtained from Mănăştur Experimental Station – Farm Cojocna in 2008–2009, in one experiment carried out using randomization blocks design with two experimental factors (mineral fertilization and period of harvest). Alfalfa quality was first determinated on 48 samples by classical analyses: crude protein CP (AOAC, 1990), crude fiber CF (Fiber Cap, FOSS, DK) and in vitro organic matter digestibility OMDrt (DeBoever, 1986). Then the samples were scanned by NIRS. Calibration models were performed by PerkinElmer Spectrum Quant + 4.21 program (USA) on the 48 samples determinated by classical analysis. The results showed fully confirmed by acceptable coefficients of determination and standard error of cross-validation (R2=0.96 for CP, 0.94 for CF, 0.98 for OMDrt and SECV=0.77 for CP, 1.35 for CF, 1.13 for OMDrt). Successful results for prediction of other 176 alfalfa samples were then obtained using these calibration models: SEP=0.869 for CP, 1.058 for CF, 1.058 for OMDrt). The highest CP and OMDrt values of alfalfa were obtained in bud stage (22.0% and 66.0% respectively). While for CF, the highest content was registered in the seed formation stage (46.0%). The NIRS technique offers us the possibility to determinate rapidly and easily Romanian alfalfa important parameters, but the system could also be used for the determination of other constituents. [less ▲]

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See detailDetermination of salbutamol enantiomers in human urine using heptakis(2,3-di-O-acetyl-6-O-sulfo)-beta-cyclodextrin in nonaqueous capillary electrophoresis
Servais, Anne-Catherine ULg; Chiap, Patrice ULg; Hubert, Philippe ULg et al

in Electrophoresis (2004), 25(10-11), 1632-1640

Nonaqueous capillary electrophoresis (NACE) was successfully applied to the resolution and the determination of salbutamol enantiomers in urine samples using heptakis(2,3-di-O-acetyl-6-O-sulfo)-beta ... [more ▼]

Nonaqueous capillary electrophoresis (NACE) was successfully applied to the resolution and the determination of salbutamol enantiomers in urine samples using heptakis(2,3-di-O-acetyl-6-O-sulfo)-beta-cyclodextrin (HDAS-beta-CD). After optimization of the electrophoretic parameters, namely the background electrolyte (BGE) composition and the HDAS-beta-CD concentration, salbutamol enantiomers were completely resolved using a BGE made up of 10 mm ammonium formate and 15 mm HDAS-beta-CD in methanol acidified with 0.75 M formic acid. Isoprenaline was selected as internal standard. Solid-phase extraction (SPE) was used for sample cleanup prior to the CE separation. Different sorbents involving polar, nonpolar interactions or dual retention mechanisms were evaluated and extraction cartridges containing both nonpolar and strong cation-exchange functionalities were finally selected. Salbutamol enantiomers recoveries from urine samples were determined. The method was then successfully validated using a new approach based on accuracy profiles over a concentration range from 375 to 7500 ng/mL for each enantiomer. [less ▲]

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See detailDetermination of secure operating limits with respect to voltage collapse
Van Cutsem, Thierry ULg; Moisse, Christel; Mailhot, Richard

in IEEE Transactions on Power Systems (1999), 14(1), 327-335

A secure operating limit is the most stressed among a given set of operating points, such that the system can withstand specified contingencies. It is a general measure of security with respect to ... [more ▼]

A secure operating limit is the most stressed among a given set of operating points, such that the system can withstand specified contingencies. It is a general measure of security with respect to incidents, incorporating pre-contingency operator or controller actions and post-contingency corrective controls. The proposed approach deals with long-term voltage stability limits. It combines a dichotomic search with quasi steady-state simulation to compute these limits with the efficiency required by real-time applications. The limit search acceleration and contingency filtering issues are also discussed. Illustrative examples are given on the Hydro-Quebec power system [less ▲]

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See detailDetermination of sex and scrapie resistance genotype in preimplantation ovine embryos.
Guignot, F.; Baril, Gerard; Dupont, Francis et al

in Molecular Reproduction and Development (2009), 76(2), 183-190

The aim of this study was to test the accuracy of genotype diagnosis after pre-amplification of DNA extracted from biopsies obtained by microblade cutting of ovine embryos and to evaluate the viability of ... [more ▼]

The aim of this study was to test the accuracy of genotype diagnosis after pre-amplification of DNA extracted from biopsies obtained by microblade cutting of ovine embryos and to evaluate the viability of biopsied embryos after vitrification/warming and transfer to recipients. Sex and PrP genotypes were determined. Sex diagnosis was done by PCR amplification of ZFX/ZFY and SRY sequences after PEP-PCR while PrP genotype determination was performed after specific pre-amplification of specific target including codons 136, 154 and 171. Embryos were collected at Day 7 after oestrus. Blastocysts and expanded blastocysts were biopsied immediately after collection whereas compacted morulae were biopsied after 24 hr of in vitro culture. Eighty-nine biopsied embryos were frozen by vitrification. Fresh and vitrified whole embryos were kept as control. DNA of biopsies was extracted and pre-amplified. Sex diagnosis was efficient for 96.6% of biopsies and PrP genotyping was determined in 95.8% of codons. After embryo transfer, no significant difference was observed in lambing rate between biopsied, vitrified control and fresh embryos (54.5%, 60% and 66.6%, respectively). Embryo survival rate was not different between biopsied and whole vitrified embryos (P = 0.38). At birth, 96.7% of diagnosed sex and 95.4% of predetermined codons were correct. Lamb PrP profiles were in agreement with parental genotype. PEP-PCR coupled with sex diagnosis and nested PCR coupled with PrP genotype predetermination are very accurate techniques to genotype ovine embryo before transfer. These original results allow planning of selection of resistant genotype to scrapie and sex of offspring before transfer of cryopreserved embryo [less ▲]

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