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See detailDirect multiple-point geostatistical simulation of edge properties for modeling thin irregularly-shaped surfaces
Huysmans, Marijke; Dassargues, Alain ULg

in Cockx, L.; Van Meirvenne, M.; Bogaert, P. (Eds.) et al 8th International Conference On Geostatistics for Environmental Applications, GeoENV’2010 (2010, September)

Thin irregularly-shaped surfaces such as clay drapes often have a major control on flow and transport in heterogeneous porous media. Clay drapes are often complex curvilinear 3-dimensional surfaces and ... [more ▼]

Thin irregularly-shaped surfaces such as clay drapes often have a major control on flow and transport in heterogeneous porous media. Clay drapes are often complex curvilinear 3-dimensional surfaces and display a very complex spatial distribution. Variogram-based stochastic approaches are often also not able to describe the spatial distribution of clay drapes since complex, curvilinear, continuous and interconnected structures cannot be characterized using only two-point statistics. Multiple-point geostatistics aims to overcome the limitations of the variogram. The premise of multiple-point geostatistics is to move beyond two-point correlations between variables and to obtain (cross) correlation moments at three or more locations at a time using "training images" to characterize the patterns of geological heterogeneity. Multiple-point geostatistics is able to reproduce thin irregularly-shaped surfaces such as clay drapes but is often computationally intensive. To capture the thin surfaces, a small grid cell size should be adopted for the training image. This results in large training images and a large search template size and thus a large CPU and RAM demand (Huysmans and Dassargues, 2009). [less ▲]

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See detailDirect n.m.r. evidence for substrate-induced conformational changes in a beta-lactamase.
Jamin, M.; Damblon, Christian ULg; Bauduin-Misselyn, A. M. et al

in Biochemical Journal (1994), 301 ( Pt 1)

Cefoxitin and other beta-lactam antibiotics with a methoxy group on the alpha-face behave as very poor substrates of the Bacillus licheniformis beta-lactamase. The kinetic properties of the enzyme ... [more ▼]

Cefoxitin and other beta-lactam antibiotics with a methoxy group on the alpha-face behave as very poor substrates of the Bacillus licheniformis beta-lactamase. The kinetic properties of the enzyme-cefoxitin system made it theoretically suitable for a detailed structural study of the acyl-enzyme. Unfortunately, soaking the crystals in cefoxitin solution did not allow detection of a crystalline acyl-enzyme complex. In contrast, direct observation by n.m.r. of the stable acyl-enzyme formed with cefoxitin and moxalactam indicated clear modifications of the enzyme structure, which were reflected in the aromatic and high-field methyl regions of the spectrum. The return to the initial free enzyme spectrum was concomitant with the hydrolysis of the acyl-enzyme, the process being slow enough to allow multidimensional n.m.r. experiments. [less ▲]

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See detailDirect nano-in-micropatterning of TiO2 thin layers and TiO2/Pt nanoelectrode arrays by deep X-ray lithography
Faustini, M.; Marmiroli, B.; Malfatti, L. et al

in Journal of Materials Chemistry (2011), 21

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See detailDirect NMR evidence for a local resriction in the segmental chain mobility of a model ionomer
Vanhoorne, Pierre; Jérôme, Robert ULg; Teyssié, Philippe et al

in Macromolecules (1994), 27(9), 2548-2552

To probe the local mobility of the chain segments directly attached to ionic multiplets, two model ionomers have been synthesized. The first one is a carboxylato-telechelic deuterated polystyrene in which ... [more ▼]

To probe the local mobility of the chain segments directly attached to ionic multiplets, two model ionomers have been synthesized. The first one is a carboxylato-telechelic deuterated polystyrene in which the chain segments bearing the sodium carboxylate end groups have been selectively protonated; the second one has a protonated polystyrene backbone terminated at both ends with a deuterated polystyrene segment bearing the sodium carboxylate groups. Both polymers have been studied by high-resolution solid-state C-13 NMR. Line-width measurements of the protonated units have clearly shown that the dipolar interactions of the sodium carboxylate end groups are responsible for a mobility restriction of the chain end segments. This experiment is thought to be the first direct evidence for the model recently proposed by Eisenberg et al. for ionomer morphology according to which the ionic multiplets are surrounded with a shell of constrained polymer segments. [less ▲]

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See detailDirect observation of microdomain morphology in "all-acrylic" thermoplastic elastomers synthesized via living radical polymerization
Leclère, Philippe; Moineau, Georges; Minet, Michaël et al

in Langmuir (1999), 15(11), 3915-3919

We investigate the microscopic morphology of thin films of symmetric triblock copolymers synthesized via a two-step “living” radical polymerization of n-butylacrylate and methyl methacrylate. These ... [more ▼]

We investigate the microscopic morphology of thin films of symmetric triblock copolymers synthesized via a two-step “living” radical polymerization of n-butylacrylate and methyl methacrylate. These copolymers with low poly(methyl methacrylate) contents constitute a new class of potential thermoplastic elastomers with higher service temperature and oxidation resistance compared to conventional polydiene−polystyrene-based thermoplastic elastomers. The straightforward synthetic pathway allows for strict control of molecular weight, molecular-weight distribution, and composition. The presence in the copolymer of immiscible segments covalently bound to each other leads to phase separation on the nanometer scale. Regular organization of the phase-separated nanodomains is observed in real space by scanning force microscopy. The data point to a strong contrast in the local mechanical properties, corresponding to the microphase morphology. Cylinders of the minority phase are found to orient perpendicular to the surface, because of the surface energy difference between the constituents. Lamellae are also arranged perpendicular to the surface, in contrast to what is usually observed in block copolymers. This particular orientation is thought to result from the symmetric character of these triblock systems, with the outer blocks more polar than the central sequence. [less ▲]

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See detailDirect observation of the depairing current density in single-crystalline Ba0.5K0.5Fe2As2 microbridge with nanoscale thickness
Li, Jun; Yuan, Jie; Yuan, Ya-Hua et al

in Applied Physics Letters (2013), 103

We investigated the critical current density (Jc) of Ba0.5K0.5Fe2As2 single-crystalline microbridges with thicknesses ranging from 276 to 18 nm. The Jc of the microbridge with thickness down to 91 nm is ... [more ▼]

We investigated the critical current density (Jc) of Ba0.5K0.5Fe2As2 single-crystalline microbridges with thicknesses ranging from 276 to 18 nm. The Jc of the microbridge with thickness down to 91 nm is 10.8 MA/cm2 at 35 K, and reaches 944.4 MA/cm2 by extrapolating Jc(T) to T = 0 K using a two-gap s-wave Ginzburg-Landau model, well in accordance with the depairing current limit. The temperature, magnetic field, and angular-dependence of Jc(T,H,q) indicated weaker field dependence and weakly anisotropic factor of 1.15 (1 T) and 1.26 (5 T), which also yielded the validity of the anisotropic Ginzburg-Landau scaling. [less ▲]

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See detailDirect parameter identification in a model of the cardiovascular system
Pironet, Antoine ULg; Dauby, Pierre ULg; Desaive, Thomas ULg

in 11th Belgian Day on Biomedical Engineering (2012, December 07)

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See detailDirect quantitative analysis of linamarin in cassava by high performance thin-layer chromatography
Bodart, Patricia; Muzembe, K. F.; Penelle, Jacques et al

Conference (1997, April)

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See detailDirect Quantitative Analysis of Linamarin in Cassava by High-Performance Thin Layer Chromatography
Bodart, Patricia; Penelle, Jacques; Angenot, Luc ULg et al

in Journal of Planar Chromatography- Modern TLC (1998), 11(January/February), 38-42

A simple, rapid and accurate HPTLC quantitative procedure is presented for the direct determination of linamarin. A cassava sample was extracted with boiling 80% v/v methanol and the extract and linamarin ... [more ▼]

A simple, rapid and accurate HPTLC quantitative procedure is presented for the direct determination of linamarin. A cassava sample was extracted with boiling 80% v/v methanol and the extract and linamarin were applied to silicagel HPTLC plates prewashed by development with methanol.The plates were first developed to a distance of 30mm with ethyl acetate-acetone-water, 40+50+10 (v/v), then to a distance of 85 mm with ethyl acetate-formic acid-water, 60+10+10 (v/v). the spots were visualized by dipping the plate into a solution af aniline (2%), and phosphoric acid 15% in acetone, then heating at 105°C for 60 min. Densitometric quantification was effected at lambda= 525 nm by transmission scanning. The method was validated for accuracy, intraday, and interday reproducibility of peak area, linearity, and detection limit. [less ▲]

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See detailDirect regeneration of rattan seedlings from apical meristem and axillary bud explants
Kouakou, L. K.; Zoro Bi, I. A.; Kouakou, T. H. et al

in Belgian Journal of Botany (2009), 142(1), 60-67

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See detailDirect responses to six generations of selection for ovulation rate or prenatal survival in Large White pigs.
Rosendo, A.; Druet, Tom ULg; Gogue, J. et al

in Journal of Animal Science (2007), 85(2), 356-64

Effects of selection for ovulation rate or prenatal survival were examined using data from 3 pigs lines derived from the same base Large White population. Two lines were selected for 6 generations on high ... [more ▼]

Effects of selection for ovulation rate or prenatal survival were examined using data from 3 pigs lines derived from the same base Large White population. Two lines were selected for 6 generations on high ovulation rate at puberty (OR line) or high prenatal survival corrected for ovulation rate in the first 2 parities (PS line). The third line was an unselected control line. Genetic parameters for ovulation rate on the left, right, and both ovaries at puberty (ORPL, ORPR, and ORP, respectively) and at fertilization (ORFL, ORFR, and ORF, respectively), total number of piglets born (TNB) per litter, prenatal survival (PS = TNB/ORF), and PS corrected for ovulation rate (CPS = PS + 0.018ORF) were estimated using REML methodology. Responses to selection were estimated by computing differences between OR or PS and control lines at each generation using least squares and mixed models methodology. Average genetic trends were computed by regressing line differences on generation number. Realized heritabilities were estimated using standard procedures. Heritability estimates were 0.17, 0.11, 0.34, 0.13, 0.09, 0.33, 0.14, 0.11, and 0.17 (SE = 0.01 to 0.03) for ORPL, ORPR, ORP, ORFL, ORFR, ORF, PS, CPS, and TNB, respectively. Realized heritabilities were 0.37 +/- 0.08 and 0.10 +/- 0.09 for ORP and CPS, respectively. The different measures of ovulation rate had strong genetic correlations (r(g) > 0.7). The ORF had midrange negative genetic correlations with PS and CPS (-0.45 +/- 0.07 and -0.42 +/- 0.08, respectively). The ORP also had an antagonistic genetic relationship with PS (-0.26 +/- 0.07) but was almost independent from CPS (-0.02 +/- 0.11). The TNB was moderately correlated with ORP and ORF (r(g) = 0.41 +/- 0.09 for both traits). Average genetic trends in OR and PS lines were, respectively, 0.49 +/- 0.10 and 0.11 +/- 0.10 for ORP, and 0.43 +/- 0.11 and 0.11 +/- 0.11 for ORF. Responses to selection were slightly superior in the left than in the right ovary. No significant difference was found for PS or CPS in any of the lines. The TNB did not change in the OR line but significantly improved in the PS line (0.24 +/- 0.11 piglets/generation). [less ▲]

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See detailDirect social costs of osteoporotic hip fractures in Belgium
Gillet, Pierre ULg; Reginster-Haneuse, G; Reginster, Jean-Yves ULg

in Osteoporosis International (1996), 6(S1), 119

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See detailDirect social costs of Osteoporotice hip fractures in Belgium
Gillet, Pierre ULg; Gosset, Christiane ULg; Reginster, Jean-Yves ULg

in Calcified Tissue International (1997), 61

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See detailDirect stimulation of cytokines (IL-1 beta, TNF-alpha, IL-6, IL-2, IFN-gamma and GM-CSF) in whole blood. I. Comparison with isolated PBMC stimulation.
De Groote, D.; Zangerlé, Pierre-François ULg; Gevaert, Y. et al

in Cytokine (1992), 4(3), 239-48

Production of interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), interleukin 2 (IL-2), interferon gamma (IFN-gamma) and granulocyte-macrophage colony ... [more ▼]

Production of interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), interleukin 2 (IL-2), interferon gamma (IFN-gamma) and granulocyte-macrophage colony-stimulating factor (GM-CSF) after stimulation by lipopolysaccharide (LPS) and phytohemagglutinin (PHA) was studied in 1/10 diluted whole blood (WB) culture and in peripheral blood mononuclear cell (PBMC) culture. Cytokines IL-1 beta, TNF-alpha and IL-6 are preferentially stimulated by LPS whereas IL-2, IFN-gamma and GM-CSF are stimulated by PHA. Combination of 5 micrograms/ml PHA and 25 micrograms/ml LPS gave the most reliable production of the six cytokines studied. IL-1 beta, TNF-alpha and IL-6 represent a homogeneous group of early-produced cytokines positively correlated among themselves and with the number of monocytes in the culture (LeuM3). Furthermore, IL-1 beta was negatively correlated with the number of T8 lymphocytes. IL-2, IFN-gamma and GM-CSF represent a group of late-produced cytokines. Kinetics and production levels of IL-6 and GM-CSF are similar in WB and PBMC cultures. In contrast, production levels of TNF-alpha and IFN-gamma are higher in WB than in PBMC whereas production levels of IL-6 and IL-2 are lower in WB than in PBMC. Individual variation in responses to PHA + LPS was always higher in PBMC cultures than in WB cultures. The capacity of cytokine production in relation to the number of mononuclear cells is higher in WB, or in PBMC having the same mononuclear cell concentration as WB, than in conventional cultures of concentrated PBMC (10(6)/ml). Because it mimics the natural environment, diluted WB culture may be the most appropriate milieu in which to study cytokine production in vitro. [less ▲]

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See detailDirect stimulations of cytokines (IL1-Beta, IL2, IL6, TNF-Alpha, IFN-Gamma, GM-CSF, LIF) in whole blood. Differences between normal and osteoporotic postmenopausal women.
Zheng, X; Vrindts, Y; de Groote, D et al

in Journal of Bone and Mineral Research (1994), 9(S1), 322

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See detailA direct symbolic approach to model checking pushdown systems
Finkel, Alain; Willems, Bernard; Wolper, Pierre ULg et al

in Electronic Notes in Theoretical Computer Science (1997), 9

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See detailDirect use of MACE EBV in the Walloon single-step Bayesian genomic evaluation system
Vandenplas, Jérémie ULg; Colinet, Frédéric ULg; Faux, Pierre ULg et al

in Journal of Dairy Science (2013, July), 96(E-Supplement),

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See detailDirect visualization of magnetic vortex pinning in superconductors
Menghini, Mariela; Kramer, R. B. G.; Silhanek, Alejandro ULg et al

in Physical Review. B : Condensed Matter (2009), 79(14),

We study the vortex structure in a Pb film deposited on top of a periodic array of ferromagnetic square microrings by combining two high-resolution imaging techniques: Bitter decoration and scanning Hall ... [more ▼]

We study the vortex structure in a Pb film deposited on top of a periodic array of ferromagnetic square microrings by combining two high-resolution imaging techniques: Bitter decoration and scanning Hall-probe microscopy (SHPM). The periodicity and strength of the magnetic pinning potential generated by the square microrings are controlled by the magnetic history of the template. When the square rings are in the magnetized dipolar state, known as the onion state, the strong stray field generated at the domain walls prevents the decoration of vortices. SHPM images show that the stray field generated by the dipoles is much stronger than the vortex field, in agreement with the results of simulations. Real-space vortex imaging has revealed that in the onion state, the corners of the square rings act as effective pinning centers for vortices. [less ▲]

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