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See detailThe Influence of Fetal and Postnatal Growth on Heart Rate Variability in Young Infants
Massin, M. M.; Withofs, Nadia ULg; Maeyns, K. et al

in Cardiology (2001), 95(2), 80-3

Heart rate variability (HRV), a measure of cardiac autonomic control, was analyzed in infants to assess the hypothesis that early undernutrition may induce autonomic dysfunction that could play a role in ... [more ▼]

Heart rate variability (HRV), a measure of cardiac autonomic control, was analyzed in infants to assess the hypothesis that early undernutrition may induce autonomic dysfunction that could play a role in the programming of later cardiovascular disease. HRV data were collected during a night session in 546 healthy infants at 5-12 weeks of adjusted age, and statistical associations with fetal and postnatal growth indices were established. A significant positive correlation between birth weight, the ratio of neonatal weight to head circumference and postnatal weight gain, and HRV indices mostly influenced by sympathetic activity was demonstrated in 11- and 12-week-old infants. A slight correlation (p > 0.05) was also found in younger infants. These data suggest the influence of fetal and postnatal growth on the programming of the autonomic nervous system beyond the neonatal period. This influence may be one of the important mechanisms that link impaired growth in fetal and infant life to high blood pressure and other cardiovascular disease during childhood and adulthood (the Barker hypothesis). [less ▲]

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See detailInfluence of Fiber Distribution and Grain Size on the Mechanical Behavior of Friction Stir Processed Mg-C Composites
Mertens, Anne ULg; Montrieux, Henri-Michel ULg; Lecomte-Beckers, Jacqueline ULg et al

Conference (2012, November 12)

Short C fibers-Mg matrix composites have been produced by friction stir processing sandwiches made of a layer of C fabric stacked between two sheets of either the ductile Mg alloy AZ31B, or of the less ... [more ▼]

Short C fibers-Mg matrix composites have been produced by friction stir processing sandwiches made of a layer of C fabric stacked between two sheets of either the ductile Mg alloy AZ31B, or of the less ductile alloy AZ91D, that is capable of age hardening. It has been shown that the choice of the optimal experimental parameters for the production of sound composites was strongly dependent on the nature of the matrix. 3D X-ray tomography reveals that the fibers orient along the onion rings and that they are more or less fragmented depending on the local shear stress during the process. The fiber volume fraction is increased when the nugget volume decreases in particular for the AZ91D base material and for a high advancing speed for the AZ31B base material. The fiber volume fraction influences directly the grain size, the hardness and the tensile properties of the composites. [less ▲]

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See detailInfluence of firing time and framework thickness on veneered Y-TZP discs curvature.
Jakubowicz-Kohen, Boris D.; Sadoun, Michael J.; Douillard, Thierry et al

in Dental materials : official publication of the Academy of Dental Materials (2013)

OBJECTIVES: The objective of the present work was to study the curvature of very thinly, veneered Y-TZP discs of different framework thicknesses submitted to different firing times. METHODS: Fifteen 20-mm ... [more ▼]

OBJECTIVES: The objective of the present work was to study the curvature of very thinly, veneered Y-TZP discs of different framework thicknesses submitted to different firing times. METHODS: Fifteen 20-mm-wide Y-TZP discs were produced in three different thicknesses: 0.75, 1, 1.5mm. One disc from each group was left unveneered while the others were layered with a 0.1mm veneering ceramic layer. All discs underwent five firing cycles for a total cumulative firing time of 30min, 1, 2, 5 and 10h at 900 degrees C. The curvature profile was measured using a profilometer after the veneering process and after each firing cycle respectively. A fitted curve was then used to estimate the, curvature radius. The coefficient of thermal expansion (CTE) measurements were taken on veneering, ceramic and Y-TZP beam samples that underwent the same firing schedule. Those data were used to calculate the curvature generated by CTE variations over firing time. RESULTS: All bilayered samples exhibited a curvature that increased over firing time inversely to framework thickness. However non-veneered samples did not exhibit any curvature modification. SIGNIFICANCE: The results of the present study reveal that even a very thin veneer layer (0.1mm) can induce a significant curvature of Y-TZP discs. The dilatometric results showed that Tg and CTE, variations are not sufficient to explain this curvature. A chemical-induced zirconia volume, augmentation located at the framework sub-surface near the interface could explain the sample, curvature and its increase with firing time. [less ▲]

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See detailThe influence of foam morphology of multi-walled carbon nanotubes/poly(methyl methacrylate) nanocomposites on electrical conductivity
Tran, Minh Phuong ULg; Detrembleur, Christophe ULg; Alexandre, Michaël ULg et al

in Polymer (2013), 54(13), 3261-3270

Polymer/multi-walled carbon nanotubes (PMMA/MWNTs) nanocomposites foams are widely investigated during the last decade thanks to their potential applications as electromagnetic interferences shielding ... [more ▼]

Polymer/multi-walled carbon nanotubes (PMMA/MWNTs) nanocomposites foams are widely investigated during the last decade thanks to their potential applications as electromagnetic interferences shielding (EMI) materials. Electrical conductivity of the nanocomposite is a key parameter for these applications. In the frame of this work, we aim at establishing relationships between the foams morphology and their electrical conductivity. We therefore first design nanocomposite foams of various morphologies using supercritical carbon dioxide (scCO2) as physical foaming agent. The nanocomposites based on poly(methyl methacrylate) (PMMA) and different carbon nanotubes loadings are prepared by melt-mixing and foamed by scCO2 in various conditions of pressure, temperature and soaking time. The influence of these foaming conditions on the morphology of the foams (volume expansion, pore size, cell density, cell-wall thickness) is discussed. After measuring the electrical conductivity of the foams, we establish structure/properties relationships that are essential for further optimizations of the materials for the targeted application. [less ▲]

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See detailThe influence of follicular dendritic cells on B-cell proliferation depends on the activation of B cells and the mitogen used.
Bosseloir, A.; Bouzahzah, F.; Defrance, T. H. et al

in Scandinavian Journal of Immunology (1996), 43(1), 23-30

Follicular dendritic cells (FDC) are unique non-lymphoid cells found only in lymph follicles. They play a part in the survival, proliferation and differentiation of B cells. To analyse the influence of ... [more ▼]

Follicular dendritic cells (FDC) are unique non-lymphoid cells found only in lymph follicles. They play a part in the survival, proliferation and differentiation of B cells. To analyse the influence of FDC on B-lymphocyte proliferation, we isolated them from human tonsils on albumin gradients and treated them with mitomycin C to prevent the multiplication of lymphoid cells harboured in their cytoplasmic evaginations. FDC cultured for 12-16 h remained attached to the substrate; non-adherent cells were carefully eliminated by washing. Purified B cells cultured alone or with contaminant-cleared FDC were maintained for 2 days in the presence or absence of various stimulants, after which tritiated thymidine uptake by these cells was measured. In the absence of activators, FDC did not induce B-cell multiplication. B cells cultured in the presence of FDC exhibited increased 3H-TdR uptake when activated with anti-CD40 MoAb, anti-immunoglobulin MoAb or transferrin, but not when stimulated with Staphylococcus aureus strain Cowan I (SAC) at a given concentration. In the latter case, B-cell proliferation clearly decreased. In control cocultures where mitomycin-C-treated non-adherent cells were used instead of FDC in the presence of the different stimulants, no increase in B-cell proliferation was observed. The results suggest that, inside the germinal centres, FDC modulation of B-cell proliferation depends on the activation state of the B cells and on the stimulant encountered. [less ▲]

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See detailInfluence of food resources on the ranging pattern of Northern pig-tailed macaques (Macaca leonina)
Albert, Aurelie; Huynen, Marie-Claude ULg; Savini, Tommaso et al

in International Journal of Primatology (2013)

Food availability may influence primates’ home range size and use. Understanding this relationship may facilitate the design of conservation strategies. We aimed to determine how fruit availability ... [more ▼]

Food availability may influence primates’ home range size and use. Understanding this relationship may facilitate the design of conservation strategies. We aimed to determine how fruit availability influences the ranging patterns of a group of northern pig-tailed macaques (Macaca leonina) living around the visitor center of Khao Yai National Park, Thailand. We predicted that macaques would increase their range during low fruit abundance periods to gather high-quality food and that they would go where there are more fruits or more fruits of particular species. We also predicted that human food, linked to human pre sence, would attract the macaques. We followed the macaques and recorded their diet and movements within their home range. We superimposed a grid on kernels defining the monthly home range surface to compare spatially macaques’ travel and the availability of fruits measured on botanical transects. Our results showed that the macaques increased their monthly home range in March, probably to obtain newly available fruits. During high fruit abundance seasons, they spent more time near particular fruit species. In August and September, although fruits became rare again, macaques kept their home range large, perhaps to find enough fruits as supplies dwindled. Finally, from October to February, they decreased their monthly home range size while consuming human food, a highquality item. In conclusion, the macaques used several ranging strategies according to fruit availability. however, we think that, without human food, macaques would tend to increase their range during low fruit abundance periods, as predicted. [less ▲]

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See detailInfluence of food resources on the ranging pattern of Northern pig-tailed macaques (Macaca leonina)
Albert, Aurelie; Huynen, Marie-Claude ULg; Savini, Tommaso et al

in International Journal of Primatology (2013)

Food availability may influence primates’ home range size and use. Understanding this relationship may facilitate the design of conservation strategies. We aimed to determine how fruit availability ... [more ▼]

Food availability may influence primates’ home range size and use. Understanding this relationship may facilitate the design of conservation strategies. We aimed to determine how fruit availability influences the ranging patterns of a group of northern pig-tailed macaques (Macaca leonina) living around the visitor center of Khao Yai National Park, Thailand. We predicted that macaques would increase their range during low fruit abundance periods to gather high-quality food and that they would go where there are more fruits or more fruits of particular species. We also predicted that human food, linked to human pre sence, would attract the macaques. We followed the macaques and recorded their diet and movements within their home range. We superimposed a grid on kernels defining the monthly home range surface to compare spatially macaques’ travel and the availability of fruits measured on botanical transects. Our results showed that the macaques increased their monthly home range in March, probably to obtain newly available fruits. During high fruit abundance seasons, they spent more time near particular fruit species. In August and September, although fruits became rare again, macaques kept their home range large, perhaps to find enough fruits as supplies dwindled. Finally, from October to February, they decreased their monthly home range size while consuming human food, a highquality item. In conclusion, the macaques used several ranging strategies according to fruit availability. however, we think that, without human food, macaques would tend to increase their range during low fruit abundance periods, as predicted. [less ▲]

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See detailThe influence of forest definition on landscape fragmentation assessment in Rondônia, Brazil
Colson, F; Bogaert, Jan ULg; Carneiro Filho, A. et al

in Ecological Indicators (2009), 9

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See detailInfluence of forest degradation on tree diversity in a forest-savannah transition in Eastern Ivory Coast
Barima, YSS; Angaman, MD; De Cannière, C et al

in International Journal of Biological and Chemical Sciences (2012), 6(4), 1467-1497

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See detailInfluence of friction in material characterization in micro-indentation measurement
Guo, Weichao ULg; Rauchs, G.; ZHang, W. H. et al

in Journal of Computational & Applied Mathematics (2010), 234

A comprehensive computational study is undertaken to identify the influence of friction in material characterization by indentation measurement based on elasto- plastic solids. The impacts of friction on ... [more ▼]

A comprehensive computational study is undertaken to identify the influence of friction in material characterization by indentation measurement based on elasto- plastic solids. The impacts of friction on load versus indentation depth curve, and the values of calculated hardness and Young's modulus in conical and spherical indentations are shown in this paper. The results clearly demonstrate that, for some elasto-plastic materials, the curves of load versus indentation depth obtained either by spherical or conical indenters with different friction coefficients, cannot be distinguished. However, if utilizing the parameter (see text for details), to quantify the deformation of piling-up or sinking-in, it is easy to find that the influence of friction on piling-up or sinking-in in indentation is significant. Therefore, the material parameters which are related to the projected area will also have a large error caused by the influence of friction. The maximum differences on hardness and Young's modulus can reach 14.59% and 6.78%, respectively, for some elastic materials shown in this paper. These results do not agree with those from researchers who stated that the instrumented indentation experiments are not significantly affected by friction. [less ▲]

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See detailThe influence of friction on elasto-plastic material in nanoindentation
Guo, Weichao ULg; Ponthot, Jean-Philippe ULg; ZHANG, W. H. et al

in Proceedings of ACOMEN’2008, Advanced Computational Methods in Engineering (2008)

A comprehensive computational study is undertaken to identify the influence of friction in nanoindentation of elasto-plastic materials, the impacts of friction on calculation results with conical and ... [more ▼]

A comprehensive computational study is undertaken to identify the influence of friction in nanoindentation of elasto-plastic materials, the impacts of friction on calculation results with conical and spherical indenters are shown in this paper. The results clearly demonstrate that, for some elasto-plastic materials, the P  h curves obtained either by spherical or conical indenters with different friction coefficients cannot be distinguished. However, if utilizing the parameter  (see text for details), to quantify the deformation of piling-up or sinking-in, it is easy to find that the influence of friction on piling-up or sinking-in in nanoindentation is significant. Therefore, the material parameters derived from the projected area will have a large error caused by the influence of friction. In this paper, the maximum error on hardness can reach 14% for some elastic materials. These results do not agree with those from researchers who stated that instrumented indentation experiments are not significantly affected by friction. Moreover, in conical indentation, friction can effectively restrain the slip on the interface between indenter and specimen, which leads to a decrease in the amount of piling-up or increase in the amount of sinking-in. However, when the half apex angle is large enough, the influence of friction becomes a minor factor in indentation. In spherical indentation, the amount of piling-up decreases or of sinking-in increases with an increasing friction coefficient. But the friction is independent of the radius of spherical indenter, the piling-up or sinking-in obtained by two different spherical indenters with varying friction coefficients are nearly identical. [less ▲]

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See detailInfluence of fuel type, dilution and equivalence ratio on the emission reduction from the auto-ignition in an Homogeneous Charge Compression Ignition engine
Machrafi, Hatim ULg; Cavadias, Simeon; Amouroux, Jacques

in Energy (2010), 35(4), 1829-1838

One technology that seems to be promising for automobile pollution reduction is the Homogeneous Charge Compression Ignition (HCCI). This technology still faces auto-ignition and emission-control problems ... [more ▼]

One technology that seems to be promising for automobile pollution reduction is the Homogeneous Charge Compression Ignition (HCCI). This technology still faces auto-ignition and emission-control problems. This paper focuses on the emission problem, since it is incumbent to realize engines that pollute less. For this purpose, this paper presents results concerning the measurement of the emissions of CO, NOx, CO2, O-2 and hydrocarbons. HCCI conditions are used, with equivalence ratios between 0.26 and 0.54, inlet temperatures of 70 degrees C and 120 degrees C and compression ratios of 10.2 and 13.5, with different fuel types: gasoline, gasoline surrogate, diesel, diesel surrogate and mixtures of n-heptane/toluene. The effect of dilution is considered for gasoline, while the effect of the equivalence ratio is considered for all the fuels. No significant amount of NOx has been measured. It appeared that the CO, O-2 and hydrocarbon emissions were reduced by decreasing the toluene content of the fuel and by decreasing the dilution. The opposite holds for CO2. The reduction of the hydrocarbon emission appears to compete with the reduction of the CO2 emission. Diesel seemed to produce less CO and hydrocarbons than gasoline when auto-ignited. An example of emission reduction control is presented in this paper. (C) 2010 Elsevier Ltd. All rights reserved. [less ▲]

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See detailInfluence of game playing on the muscular profile of shoulder rotators of handball players
Ucay, O.; Gasq, D.; Forthomme, Bénédicte ULg et al

in European Journal of Sports Medicine (2013, September), 1(1), 105

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See detailInfluence of Garlic Intercropping or Active Emitted Volatiles in Releasers on Aphid and Related Beneficial in Wheat Fields in China
Haibo, Zhou; Chen, Julian; Yong, Liu et al

in Journal of Integrative Agriculture (2013), 12(3)

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See detailThe influence of gas depth on interfacial convection in a liquid gas bilayer.
Narayanan, Ranga; Theisen, Eric; Johnson, Duane et al

in Bulletin of the American Physical Society, Proceedings of the 54th Annual Meeting of the APS Division of Fluid Dynamics (2001, November 01)

We present a study of the influence of air height on the pattern formation at the onset of interfacial convection in a liquid -gas bilayer. Bilayer convection results from interaction of two immiscible ... [more ▼]

We present a study of the influence of air height on the pattern formation at the onset of interfacial convection in a liquid -gas bilayer. Bilayer convection results from interaction of two immiscible, superposed fluid layers and it is a transport problem that is affected by the ratios of various thermophysical properties and geometries. By using both calculations and experiments, a new convection-coupling mechanism is revealed. When the gas depth is low the convection is dominant in the liquid. It is of the Rayleigh Marangoni type and subcritical convection may be seen for axisymmetric patterns at the onset. For large gas heights the convection in the upper fluid layer simultaneously generates transverse thermal gradients along the fluid-fluid interface immediately causing surface tension gradient and buoyancy driven-convection in the lower fluid. The convection in the gas is of the Rayleigh type and the self-adjoint nature of the mathematical problem is depicted in the experiment wherein no subcritical motion occurs. In both the calculations and the experiment, silicone oil and air were used as the two fluids. As the viscosity of air is quite low compared to the silicone oil, convection in the air has no mechanical influence on the silicone oil and it is this property that is advantageous in isolating the new convection mechanism. The correspondence between theory and experiment is excellent. [less ▲]

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See detailInfluence of gas species on backdraft probability using a diffusion flame limits criterion
Pérez Jiménez, Christian; Franssen, Jean-Marc ULg; Karlsson, Bjorn

in Journal of Fire Sciences (2009), 27(2), 143-156

Backdraft is a limited-ventilation fire phenomenon closely linked to the unburnt gases accumulated in the fire compartment just before creating an opening that allows a new supply of oxygen to enter the ... [more ▼]

Backdraft is a limited-ventilation fire phenomenon closely linked to the unburnt gases accumulated in the fire compartment just before creating an opening that allows a new supply of oxygen to enter the compartment. The aim of this article is to help understanding the influence of gas species such as hydrocarbon CmHn, water, carbon dioxide, oxygen, and nitrogen on backdraft probability. The influence of increasing the number of moles of the above gas species as well as the number of atoms of carbon, hydrogen, and oxygen in the fuel composition is analyzed. For this purpose, a diffusion flame limit criterion based on Le Chatelier's rule is used. In order to verify the obtained results, validation with 41 backdraft experiments is carried out. [less ▲]

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See detailInfluence of Gaussian beams on the reconstruction of digital Fourier holograms
Roose, Stéphane ULg; Stijns, Erik

Scientific conference (1989, June 01)

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See detailInfluence of gaze direction on face recognition: A sensitive effect
Daury, Noémy ULg

in Psychologica Belgica (2011), 51(2), 139-153

This study was aimed at determining the conditions in which eye-contact may improve recognition memory for faces. Different stimuli and procedures were tested in four experiments. The effect of gaze ... [more ▼]

This study was aimed at determining the conditions in which eye-contact may improve recognition memory for faces. Different stimuli and procedures were tested in four experiments. The effect of gaze direction on memory was found when a simple “yes-no” recognition task was used but not when the recognition task was more complex (e.g. including “Remember-Know” judgements, cf. Experiment 2, or confidence ratings, cf. Experiment 4). Moreover, even when a “yes-no” recognition paradigm was used, the effect occurred with one series of stimuli (cf. Experiment 1) but not with another one (cf. Experiment3). The difficulty to produce the positive effect of gaze direction on memory is discussed. [less ▲]

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See detailInfluence of gender and season on reduced glutathione concentration and energy reserves of Gammarus roeseli
Gismondi, Eric ULg; Beisel, Jean-Nicolas; Cossu-Leguille, Carole

in Environmental Research (2012), 118

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