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See detailA Growth Model of Global Imbalances
Artige, Lionel ULg; Cavenaile, Laurent ULg

Conference (2011, August 29)

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See detailA Growth Model of Global Imbalances
Artige, Lionel ULg; Cavenaile, Laurent ULg

E-print/Working paper (2010)

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See detailA Growth Model of Global Imbalances
Artige, Lionel ULg; Cavenaile, Laurent ULg

Conference (2011, March 18)

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See detailGrowth models with internal competition
Ausloos, Marcel ULg; Vandewalle, Nicolas ULg

in Acta Physica Polonica B (1996), 27(3), 737-746

Combined statistical physics and computation modelling give new instruments for the study of non-equilibrium systems. We briefly review generalized Eden and Diffusion-Limited Aggregation models as applied ... [more ▼]

Combined statistical physics and computation modelling give new instruments for the study of non-equilibrium systems. We briefly review generalized Eden and Diffusion-Limited Aggregation models as applied to spreading phenomena. We indicate the occurence of non-universal behaviors. [less ▲]

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See detailGrowth of carbon nanotubes on metal nanoparticles: a microscopic mechanism from ab initio molecular dynamics simulations
Raty, Jean-Yves ULg; Gygi, F.; Galli, G.

in Physical Review Letters (2005), 95(9), 0961031-09610340961034

We report on ab initio molecular dynamics simulations of the early stages of single-walled carbon nanotube (SWCNT) growth on metal nanoparticles. Our results show that a sp2 bonded cap is formed on an ... [more ▼]

We report on ab initio molecular dynamics simulations of the early stages of single-walled carbon nanotube (SWCNT) growth on metal nanoparticles. Our results show that a sp2 bonded cap is formed on an iron catalyst, following the diffusion of C atoms from hydrocarbon precursors on the nanoparticle surface. The weak adhesion between the cap and iron enables the graphene sheet to "float" on the curved surface, as additional C atoms covalently bonded to the catalyst "hold" the tube walls. Hence the SWCNT grows capped. At the nanoscale, we did not observe any tendency of C atoms to penetrate inside the catalyst, consistent with total energy calculations showing that alloying of Fe and C is very unlikely for 1 nm particles. Root growth was observed on Fe but not on Au, consistent with experiment [less ▲]

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See detailGrowth of Cayley and diluted Cayley trees with two kinds of entities
Vandewalle, Nicolas ULg; Ausloos, Marcel ULg

in Journal of Physics : A Mathematical & General (1996), 29(22), 7089-7104

A kinetic growth model derived from the magnetic Eden model is introduced in order to simulate the growth of hierarchical structures, such as Cayley trees. We only consider the case where two kinds of ... [more ▼]

A kinetic growth model derived from the magnetic Eden model is introduced in order to simulate the growth of hierarchical structures, such as Cayley trees. We only consider the case where two kinds of entities are competing with each other can be further subjected to an external field. The very relevant case in which both kinds of entities have different coordination numbers is introduced here for the first time, and is called the diluted Cayley tree. Physical and geometrical properties of the finite and infinite trees are exactly found and simulated. Finite-size effects are emphasized and illustrated on the global or local magnetization and on the chemical activity. Asymptotic limits are given in each case. The generated patterns can be related to a correlated percolation problem briefly discussed in the appendix. [less ▲]

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See detailGrowth of Chlorella in the presence of organic carbon: A photobioreactor study
Miazek, Krystian ULg; Goffin, Dorothée ULg; Richel, Aurore ULg et al

Scientific conference (2014, June 19)

In this study, the effect of organic carbon supplementation at low light intensity on Chlorella sorokiniana growth was evaluated. Addition of 1 g/L of acetate to media gave the highest growth rate and ... [more ▼]

In this study, the effect of organic carbon supplementation at low light intensity on Chlorella sorokiniana growth was evaluated. Addition of 1 g/L of acetate to media gave the highest growth rate and provided stable high biomass culture during prolonged cultivation time. Glucose at 1 – 5 g/L also improved biomass growth rate, although stability of high biomass culture could not be achieved. Overall, the presence of organic carbon can considerably enhance Chlorella growth when low light intensity is applied. [less ▲]

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See detailGrowth of Chlorella in vanillin enriched medium
Miazek, Krystian ULg; Goffin, Dorothée ULg; Richel, Aurore ULg

Poster (2013, August)

In this work the effect of different concentration of vanillin on the growth of Chlorella culture was evaluated. Two concentrations of vanillin: 60 mg/L and 300 mg/L in Bold Basal Medium (BBM) were tested ... [more ▼]

In this work the effect of different concentration of vanillin on the growth of Chlorella culture was evaluated. Two concentrations of vanillin: 60 mg/L and 300 mg/L in Bold Basal Medium (BBM) were tested and an inoculum from a two month Chlorella sp. (CCBA) culture was used. Vanillin at concentration of 60 mg/L showed to possess stimulating effect on Chlorella growth during 11 days of cultivation. Stimulation of Chlorella started on 3rd day of growth and was accompanied by 87% decrease of vanillin concentration within first 3 days of cultivation and its complete removal from growth media after 7 days. The acceleration of Chlorella growth in vanillin containing medium was detected due to biomass density, up to 1.2 times bigger than in the control culture, but also by measurement of chlorophyll content. Increased amount of chlorophyll content, up to 1.35 times higher than in control, was found between 4th and 11th day of cultivation. The response of Chlorella towards higher concentration of vanillin (300 mg/L) was different when compared to experiments where only 60 mg/L was used. During first 4 days of cultivation, strong inhibition of Chlorella exposed to 300 mg/L vanillin was observed and vanillin concentration maintained at the same initial concentration. During next days, a recovery effect occurred as biomass density and chlorophyll content gradually increased in comparison to the onset of growth and vanillin concentration decreased to 2 % of its initial value. Biomass density measured in Chlorella culture on 11th day was much higher than at the beginning of cultivation but still by 40% smaller than in control and by 50% smaller than in the culture growing in medium with 60 mg/L of vanillin. Chlorophyll content at the end of cultivation constituted 50% of control value and 35% of chlorophyll culture with 60 mg/L vanillin in medium. [less ▲]

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See detailGrowth of high quality InP layers in STI trenches on miscut Si (001) substrates
Wang, Gang; Leys, Maarten; Nguyen, Ngoc Duy ULg et al

in Journal of Crystal Growth (2011), 315

In this work, we report the selective area epitaxial growth of high quality InP in shallow trench isolation (STI) structures on Si (0 0 1) substrates 6° miscut toward (1 1 1) using a thin Ge buffer layer ... [more ▼]

In this work, we report the selective area epitaxial growth of high quality InP in shallow trench isolation (STI) structures on Si (0 0 1) substrates 6° miscut toward (1 1 1) using a thin Ge buffer layer. We studied the impact of growth rates and steric hindrance effects on the nano-twin formation at the STI side walls. It was found that a too high growth rate induces more nano-twins in the layer and results in InP crystal distortion. The STI side wall tapering angle and the substrate miscut angle induced streric hindrance between the InP facets and the STI side walls also contribute to defect formation. In the [-1 1 0] orientated trenches, when the STI side wall tapering angle is larger than 10°, crystal distortion was observed while the substrate miscut angle has no significant impact on the InP defect formation. In the [-1 1 0] trenches, both the increased STI tapering angle and the substrate miscut angle induce high density of defects. With a small STI tapering angle and a thin Ge layer, we obtained extended defect free InP in the top region of the [1 1 0] trenches with aspect ratio larger than 2. [less ▲]

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See detailGrowth of III/V materials on large area silicon
Schineller, Bernd; Nguyen, Ngoc Duy ULg; Heuken, Michael

in ECS Transactions (2010), 28

Continuous miniaturization has been at the heart of advances in modern semiconductor electronics. However, further scalability has seen its limits for conventional CMOS technology due to short channel ... [more ▼]

Continuous miniaturization has been at the heart of advances in modern semiconductor electronics. However, further scalability has seen its limits for conventional CMOS technology due to short channel effects. To further increase the performance for the 32 and 22 nm nodes, channel engineering introducing III-V materials may be necessary. Hence, epitaxial growth and processing strategies have to be developed which combine the high complexity of an MOCVD growth chamber with the requirements of the silicon industry. [less ▲]

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See detailGrowth of pulmonary artery after arterial switch operation for simple transposition of the great arteries.
Massin, M. M.; Nitsch, G. B.; Dabritz, S. et al

in European Journal of Pediatrics (1998), 157(2), 95-100

This retrospective study attempts to assess the size and growth pattern of the pulmonary artery about 1 year after neonatal arterial switch operation for simple transposition of the great arteries. Sixty ... [more ▼]

This retrospective study attempts to assess the size and growth pattern of the pulmonary artery about 1 year after neonatal arterial switch operation for simple transposition of the great arteries. Sixty-seven patients underwent cardiac catheterization, including catheterization of the right and left pulmonary arteries, and right ventricular angiography an average of 13.9 months after arterial switch operation. In 34 of these patients pre-operative right ventricular angiocardiograms were available. The diameter of the main pulmonary artery and that of its proximal right and left branches were measured. The values were compared to those of normal children matched for body surface area, taken from the literature and, for the branch values, related to the degree of branch stenosis and to the corresponding values, measured on pre-operative angiocardiograms. The cross-section of the main pulmonary artery after arterial switch operation with Lecompte manoeuvre becomes oval. The branches of the pulmonary artery are sometimes underdeveloped and this finding is related to branch stenosis. The ratio of the branch gradients is inversely proportional to the growth ratio of both branches while the pre- and postoperative Nakata indices are identical. CONCLUSION: The Lecompte manoeuvre induces a flattening of the main pulmonary artery with concomitant reduction of its cross-sectional area. There is also frequently trivial or rarely moderate branch pulmonary stenosis which is accompanied by growth retardation of the concerned branch. [less ▲]

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See detailGrowth of Straight InAs-on-GaAs Nanowire Heterostructures
Messing, Maria E; Wong-Leung, Jennifer; Zanolli, Zeila ULg et al

in Nano Letters (2011), 11(9), 3899-3905

One of the main motivations for the great interest in semiconductor nanowires is the possibility of easily growing advanced heterostructures that might be difficult or even impossible to achieve in thin ... [more ▼]

One of the main motivations for the great interest in semiconductor nanowires is the possibility of easily growing advanced heterostructures that might be difficult or even impossible to achieve in thin films. For III␣V semiconductor nanowires, axial heterostructures with an interchange of the group III element typically grow straight in only one interface direction. In the case of InAs␣GaAs heterostructures, straight nanowire growth has been demonstrated for growth of GaAs on top of InAs, but so far never in the other direction. In this article, we demonstrate the growth of straight axial heterostructures of InAs on top of GaAs. The heterostructure interface is sharp and we observe a dependence on growth parameters closely related to crystal structure as well as a diameter dependence on straight nanowire growth. The results are discussed by means of accurate first principles calculations of the inter- facial energies. In addition, the role of the gold seed particle, the effect of its composition at different stages during growth, and its size are discussed in relation to the results observed. [less ▲]

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See detailGrowth of subtropical forests in Miocene Europe: The roles of carbon dioxide and Antarctic ice volume
Hamon, N.; Sepulchre, P.; Donnadieu, Y. et al

in Geology (2012), 40

The middle Miocene is a crucial period for the evolution of apes, and it corresponds to their <br />appearance in Europe. The dispersion of apes was made possible by tectonic changes and the <br ... [more ▼]

The middle Miocene is a crucial period for the evolution of apes, and it corresponds to their <br />appearance in Europe. The dispersion of apes was made possible by tectonic changes and the <br />expansion of their habitat, (sub-) tropical forest, in Europe. The context in which the middle <br />Miocene climatic optimum occurred still lacks constraints in terms of atmospheric pCO2 and <br />ice-sheet volume and extent. Using a coupled atmosphere-ocean general circulation model <br />(GCM) and dynamic vegetation model, we investigated the sensitivity of Miocene climate and <br />vegetation to pCO2 levels and Antarctic ice-sheet confi gurations. Our results indicate that <br />higher than present pCO2 is necessary to simulate subtropical forest in Western and Central <br />Europe during the middle Miocene, but that a threshold at high pCO2 makes subtropical <br />forest partly collapse. Moreover, removing ice over Antarctica modifi es oceanic circulation <br />and induces warmer and slightly wetter conditions in Europe, which are consistent with the <br />expansion of subtropical forest. These results suggest that a small East Antarctic Ice Sheet <br />(25% of present-day ice volume) together with higher than present pCO2 values are in better <br />agreement with available European middle Miocene data. [less ▲]

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See detailGrowth patterns of Belgian Blue replacement heifers and growing males in commercial farms
de Behr, Vanessa; Hornick, Jean-Luc ULg; Cabaraux, Jean-François ULg et al

in Livestock Production Science (2001), 71

A survey was carried out to propose models of growth curves in Belgian Blue cattle less than 20 months of age and raised in commercial farms in southern Belgium. Live weight data were recorded between ... [more ▼]

A survey was carried out to propose models of growth curves in Belgian Blue cattle less than 20 months of age and raised in commercial farms in southern Belgium. Live weight data were recorded between 1993 and 1999 from 1104 breeding heifers, and 924 growing males. The linear, polynomial group, power, logistic, Brody, Gompertz, von Bertalanffy and Richards models were used and compared. A step-wise linear growth model characterized by two periods of linear growth was also evaluated. This last model has been proposed as the reference model to characterize the growth curves of Belgian Blue cattle less than 20 months old. The animals were then ranked and divided in subgroups based on percentiles and quartiles in order to compare their performances. The subgroups performing better presented a greater homogeneity. The males ranked above the 90th percentile presented a growth rate comparable to that of young males selected for artificial insemination. Cattle ranked above the third quartile presented a growth rate comparable to that of licensed animals. When reproduction performances were related to the growth rate, it appeared that the better growing heifers were bred younger and heavier than lesser performing animals. [less ▲]

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See detailGrowth performance and meat quality of stress negative Piétrain pigs in the tropics: the case of Vietnam
Ha Xuan, Bo; Do Duc, Luc ULg; Moula, Nassim ULg et al

Poster (2013, October 11)

This study was carried out at the animal farm of Hanoi University of Agriculture, Vietnam to evaluate the growth performance and meat quality of stress negative Piétrain pigs. The study concerns the body ... [more ▼]

This study was carried out at the animal farm of Hanoi University of Agriculture, Vietnam to evaluate the growth performance and meat quality of stress negative Piétrain pigs. The study concerns the body weight (BW) of 116 pigs at 7.5 months of age and the ultrasound measurements on 83 live animals in order to determine backfat thickness, longissimus muscle depth and lean meat percentage (LM). Meat color (C.I.E L*, a* and b*), peak shear force (SF), pH at 24h (pH24) and at 45 minutes (pH45) post mortem were measured on 31 meat samples. Meat chemical composition (dry matter, protein, lipids and ash) was determined on 23 meat samples. All the data were analyzed according to a linear fixed model including gender effect (female and intact males) and Halothane genotype (CC and CT). The interaction between gender and genotype was not observed and therefore it was ignored from the final model. The results show that BW and LM were not significantly different between genotypes (P>0.21) while females were heavier than males (101.11 vs. 93.85 kg, P=0.0011). LM of female and male were respectively 63.27 and 63.56%. Gender and genotype didn’t affect meat quality and chemical composition (P>0.05) except pH24 (P=0.0011), a* (P<0.0001) and lipids (P=0.0012) for gender effect. The pH45 (6.50 and 6.45 for females and males) and pH24 (5.34 and 5.49 for females and males) were in the range corresponding to a normal meat. The obtained results show that stress negative Piétrain pigs have high lean meat percentage and satisfactory meat quality under tropical climatic conditions in Vietnam. [less ▲]

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See detailGrowth performance and sperm quality of stress negative Piétrain boars and their hybrids with Duroc
Do Duc, Luc ULg; Ha Xuan, Bo; Farnir, Frédéric ULg et al

in Journal of Science and Development (2013), 11(2),

This study was conducted to evaluate the effects of genetic background and season on growth performance and semen quality of boars. Five genetic groups were evaluated, including stress-negative Piétrain ... [more ▼]

This study was conducted to evaluate the effects of genetic background and season on growth performance and semen quality of boars. Five genetic groups were evaluated, including stress-negative Piétrain boars with CC (PiCC) or CT (PiCT) halothane genotypes, and Piétrain x Duroc hybrid boars with various compositions (25% (PiDu25), 50% (PiDu50) or 75% (PiDu75) of Piétrain origin). The results showed that genetic group has a significant effect on growth performance and semen quality. The hybrid boars PiDu25, PiDu50 and PiDu75 had better growth rate, but lower lean <br />meat in comparison with pure stress-negative Piétrain, except PiDu75 boars. PiDu25, PiDu50 and PiCC boars demonstrated high semen quality. A season effect was observed on most of semen quality traits of pure stress-negative Piétrain as well as hybrid boars with different genetic constitution. Sperm concentration was lower in Summer and Autumn, higher in Winter and Spring. The Piétrain x Duroc hybrid boars, especially PiDu75 seem to be promising as terminal boars. [less ▲]

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See detailGrowth performances, carcass and organs characteristics and economics results of growing indigenous senegal chickens fed diets containing various levels of leuceana leucocephala (Lam.) leaves meal (2011)
Ayssiwede, Simplice; Chrysostome, C.A.A.M.; Zanmenou, J.C. et al

in International Journal of Poultry Sciences (2011), 10(9), 1132-1145

The aim of this study carried out from September to December 2010 was to evaluate the effects of Leuceana leucocephala leaves meal inclusion in the diets on growth performances, carcass and organs ... [more ▼]

The aim of this study carried out from September to December 2010 was to evaluate the effects of Leuceana leucocephala leaves meal inclusion in the diets on growth performances, carcass and organs characteristics and economics results of growing indigenous Senegal chickens. One hundred and four (104) indigenous Senegal chicks of 4 weeks old were randomly allocated into four groups of 26 chicks each with similar body weight. Each group subdivided in two repetitions of 13 birds, corresponded to each of the four (4) dietary treatments LL0, LL7, LL14 and LL21 containing respectively 0, 7, 14 and 21% of Leuceana leaves meal in substitution of groundnut cake meal. During the experiment (5-17th week old), zootechnical parameters of birds and economical data were recorded and analyzed per dietary treatment. At the end of the 13 weeks trial, the final Live Body Weights (LBW) were 864 g, 1166.48 g, 905 g and 887.16 g/bird, the Average Daily Weight Gain (ADWG) were 7.77 g, 10.88 g, 8.15 g and 8.10 g/day, the Daily Feed Intake (DFI) of 39.86 g, 51 g, 40.39 g and 44.75 g/bird and the Feed Conversion Ratio (FCR) of 7.04, 5.54, 6.27 and 6.80 respectively for birds fed LL0, LL7, LL14 and LL21 diets. The Leuceana leaves meal inclusion in the diets up to 21% had not caused any adverse effect on LBW, ADWG, DFI, FCR, mortality, carcass and organs characteristics in birds compared to their controls. Apart from the dark yellowing of abdominal fat of carcasses from birds fed LL21 diet, significantly better growth performances, feed costs and economic margins were recorded in birds fed LL7 and LL14 diets. Thus, these two dietary treatments were the only most economically profitable (respectively 214 and 48 FCFA/kg carcass of additional profit) compared to the control. [less ▲]

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