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See detailStudy of the stability and the physical property changes of amorphous inulin during moisture adsorption
Ronkart, S.; Paquot, Michel ULg; Fougnies, C. et al

Poster (2008, July)

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See detailLes aventures du transcendantal. Dialectique et politique de la pensée chez Merleau-Ponty
Janvier, Antoine ULg

in Archives du Groupe de recherches matérialistes (2008)

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See detailAPPLYING L. MANEVITCH’S COMPLEXIFICATION – AVERAGING METHOD TO ANALYZE CONDITIONS FOR OPTIMAL TARGETED ENERGY TRANSFER IN COUPLED OSCILLATORS WITH ESSENTIAL STIFFNESS NONLINEARITY
Sapsis, Themistoklis; Quinn, D. Dane; Gendelman, Oleg et al

in International Conference on Nonlinear Phenomena in Polymer Solids and Low-Dimensional Systems. Moscou, 2008 (2008, July)

We study targeted energy transfer (TET) [1] from a linear damped oscillator (LO) to a light attachment with essential stiffness nonlinearity, caused by 1:1 transient resonance capture (TRC). First, we ... [more ▼]

We study targeted energy transfer (TET) [1] from a linear damped oscillator (LO) to a light attachment with essential stiffness nonlinearity, caused by 1:1 transient resonance capture (TRC). First, we study the underlying Hamiltonian dynamics and show that for sufficiently weak damping, the nonlinear damped transitions of the system are strongly influenced by the underlying topological structure of periodic and quasiperiodic orbits of the hamiltonian system. Then, we formulate conditions that lead to effective or even optimal TET from the linear system to the nonlinear attachment. Direct analytical treatment of the governing strongly nonlinear damped equations of motion is performed by applying L. Manevitch’s complexification – averaging (CX-A) method [2] to perform slow-fast partition of the transient responses, and analytically model the dynamics in the region of optimal TET. This analysis determines the characteristic time scales of the dynamics that influence the capacity of the nonlinear attachment to passively absorb and locally dissipate broadband energy from the linear oscillator in an optimal fashion. [less ▲]

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See detailEvidence for short-term variations in two O-type stars
De Becker, Michaël ULg; Linder, Natacha ULg; Rauw, Grégor ULg

in Information Bulletin on Variable Stars (2008), 5841

Only a few O-type stars are known to display short-term (a fraction of a day) variations. Intense spectroscopic monitoring of the ON8V star HD 13268 revealed low amplitude variations with periods of ... [more ▼]

Only a few O-type stars are known to display short-term (a fraction of a day) variations. Intense spectroscopic monitoring of the ON8V star HD 13268 revealed low amplitude variations with periods of several hours. In addition, observations of the SB1 system HD 15137 revealed variations on a time scale of a few hours. We consider these stars to be a good candidates for non radial pulsations, even though variations related to inhomogeneities in a circumstellar disk can not be rejected. [less ▲]

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See detailCommunity-Based Health Insurance Schemes in Africa: Which Factors Really Induce Membership ?
Defourny, Jacques ULg; Failon, Julie ULg

Conference (2008, July)

Health micro-insurance systems have experienced a fast development for some fifteen years in sub-Saharan Africa as a means of improving the access of the poor to healthcare services. The present article ... [more ▼]

Health micro-insurance systems have experienced a fast development for some fifteen years in sub-Saharan Africa as a means of improving the access of the poor to healthcare services. The present article focuses mainly on community-based health insurance (CBHI) systems, as they currently constitute one of the most developed forms of health micro-insurance. However, it must be acknowledged that the enrolment rates remain particularly weak and coverage of the target population only rarely reaches 10%. Several authors have already observed this fact and undertaken research on the factors which influence enrolment. Nevertheless, the methodologies used, size of the samples, characteristics of the surveyed individuals, inclusion or not of non-members in the surveys, geographical areas etc. vary a lot from one author to the other. This is why this article aims at synthesizing the empirical studies carried out to date and to identify major concurring results beyond methodological differences. We finally come out with two factors which seem to play a major role and six others which seem to have a significant influence on enrolment, while surveys do not confirm the role of various other variables. We conclude with some lessons regarding the roles of the promoters and supporting NGOs in the establishment of CBHI schemes. [less ▲]

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See detailComputing Convex Hulls by Automata Iteration
Cantin, François ULg; Legay, Axel; Wolper, Pierre ULg

in Lecture Notes in Computer Science (2008, July), 5148

This paper considers the problem of computing the real convex hull of a finite set of n-dimensional integer vectors. The starting point is a finite-automaton representation of the initial set of vectors ... [more ▼]

This paper considers the problem of computing the real convex hull of a finite set of n-dimensional integer vectors. The starting point is a finite-automaton representation of the initial set of vectors. The proposed method consists in computing a sequence of automata representing approximations of the convex hull and using extrapolation techniques to compute the limit of this sequence. The convex hull can then be directly computed from this limit in the form of an automatonbased representation of the corresponding set of real vectors. The technique is quite general and has been implemented. Also, our result fits in a wider scheme whose objective is to improve the techniques for converting automata-based representation of constraints to formulas. [less ▲]

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See detailStrategies to incorporate genomic prediction into population-wide genetic evaluations
Gengler, Nicolas ULg; VanRaden, P. M.

in Journal of Dairy Science (2008, July), 91

Most current research on genomic selection is focusing on the accurate prediction of genomic breeding values. However selection solely based on genomic breeding values, despite being theoretically ... [more ▼]

Most current research on genomic selection is focusing on the accurate prediction of genomic breeding values. However selection solely based on genomic breeding values, despite being theoretically promising, is in practice only suboptimal for several reasons. The two most important are that only few animals are genotyped therefore having genomic prediction directly available and that rankings will change. With genomic breeding values potentially available in the near future, strategies are required to avoid any confusion in the mind of users. The aim of this study is to present three different strategies that could be used to incorporate genomic prediction into population-wide genetic evaluation. The three strategies are: 1) using selection index theory to combine both sources of information into a single set of breeding values; 2) for ungenotyped animals, compute conditional expectation of gene contents for SNP given molecular and pedigree data and use these predicted gene contents; and 3) integrate genomic breeding values as external information into genetic evaluation using a Bayesian framework. If strategy 1) is straight forward, additional steps have to be done to adjust breeding values for changes in those of relatives. A practical implementation is to use reliabilities of the genomic prediction, the population-wide genetic evaluation PA, and PA from the genotyped subset to set up a 3 x 3 matrix for each animal, with off-diagonal elements being functions of the 3 reliabilities. The use of strategy 2) is computationally much more challenging but leads directly to the needed covariance structures combining genomic relationship if known with pedigree relationships. Strategy 3) is potentially a good compromise because the theory is well established and has already been used in beef cattle to incorporate external breeding values. Also current genetic evaluation software can be easily modified to incorporate genomic breeding values [less ▲]

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See detailEffects of allele frequency estimation on genomic predictions and inbreeding coefficients.
VanRaden, P. M.; Tooker, M. E.; Gengler, Nicolas ULg

in Journal of Dairy Science (2008, July), 91

Genetic calculations often require estimating allele frequencies, which differ across time due to selection and drift. Data were 50,000 simulated markers and 39,985 actual markers for 2391 genotyped ... [more ▼]

Genetic calculations often require estimating allele frequencies, which differ across time due to selection and drift. Data were 50,000 simulated markers and 39,985 actual markers for 2391 genotyped Holstein bulls. Gene content of relatives and gene frequencies in the base (founder) population were estimated using pedigrees and a linear model. Ancestors born since 1950 were included, for a total of 22,088 animals. Because pedigrees were very complete, only one unknown-parent group was used. Convergence to 5 digits of accuracy required about 1000 iterations. Total time was 2 processor days and proportional to number of animals times markers, but actual clock time was reduced by processing loci on separate chromosomes in parallel. Simple allele frequencies were obtained from only the known genotypes. True base frequencies were correlated with estimated base frequencies by 0.98 versus 0.94 with simple frequencies. Genomic predictions and inbreeding coefficients were computed in four ways, using true or estimated base frequencies, simple frequencies, or an “estimate” of .5 for each marker. When allele frequencies estimates were used instead of 0.5 to assign mixed model coefficients, solutions converged more slowly but predictions were more accurate. From simulated data, realized reliabilities for young bulls were 62.8% using either true or estimated base frequencies, 62.6% using simple frequencies, and 62.0% using frequencies set to 0.5. Pedigree and genomic inbreeding coefficients were correlated by 0.73 using true base frequencies, 0.67 using estimated base frequencies, 0.12 using simple frequencies, and 0.72 when frequencies were set to 0.5. Genomic inbreeding coefficients were biased downward by 7% to 9% using either frequency estimate, upward by 31% using 0.5, but were reasonable when true frequencies were used. Frequency estimation had small effects on genomic predictions but large effects on genomic inbreeding coefficients in both simulated and real data. [less ▲]

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See detailDroixhe à l'heure de la requalification
Frankignoulle, Pierre ULg

Article for general public (2008)

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See detailSize-adaptive spherical receptor acceleration method for acoustical ray tracing
Lesoinne, Stéphane ULg; Embrechts, Jean-Jacques ULg

in Proceedings of the 5th Forum Acusticum "Acoustics '08" (2008, July)

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See detailUpstream migration of fish at natural obstructions and fish passes efficiency in Southern Belgium.
Ovidio, Michaël ULg; Orban, Patrice; Lambot, Francis et al

Conference (2008, July)

Fragmentation of rivers by physical obstacles has resulted in the drastic range reduction or extinction of numerous diadromous and potadromous species of fish worldwide. In order to implement to partially ... [more ▼]

Fragmentation of rivers by physical obstacles has resulted in the drastic range reduction or extinction of numerous diadromous and potadromous species of fish worldwide. In order to implement to partially or completely re-establish the free movements of fish in the entire watercourse, the Walloon regional government (Southern Belgium) initiated an integrated restoration project whose objectives are 1) To perform a complete inventory of all obstacles that may potentially interfere with the longitudinal connectivity and the free movements of fish, 2) To test, using radio telemetry, the ability of representative fish species (Salmonidae, Thymallidae, Cyprinidae, Esocidae and Cottidae) to clear different typologies of physical obstacles, 3) To determine the problematic sites that should be improved with priority. 4) To construct fish passage facilities and to examine their biological efficiencies. During our talk we will synthesize the results of ten years of research and define the different options for the future. [less ▲]

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See detailUm chapéu amarelo e um capuz vermelho: uma leitura semiótica de Chapeuzinho Amarelo de Chico Buarque
Lindenberg Lemos, Carolina ULg

in CASA : Cadernos de Semiótica Aplicada (2008), 6(1), 1-12

In the 1970’s, Chico Buarque published the children's book Chapeuzinho Amarelo – a parody of the fairy tale The Little Red Riding Hood. This analysis tries to emphasize the intertextual structures ... [more ▼]

In the 1970’s, Chico Buarque published the children's book Chapeuzinho Amarelo – a parody of the fairy tale The Little Red Riding Hood. This analysis tries to emphasize the intertextual structures underlying the two stories, showing in what ways elements of the narrative, themes and figures are borrowed from the classical text. In the traditional version of the brothers Grimm, the central theme is that of transgression, but in the background we can also see the theme of maturation. This secondary theme is brought to the center in Chapeuzinho Amarelo. Linguistic, sound and visual resources of the expression plane will bring a symbolic aspect to the confrontation between Chapeuzinho Amarelo and the Wolf. To close the analysis, we investigate the pictures that compose the book. These pictures bring contributions to the meanings conveyed by the written text and reinforce the general interpretation given in this work. [less ▲]

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See detailLa cité administrative de Liège
Charlier, Sébastien ULg

in Nouvelles du Patrimoine (Les) (2008), 121

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See detailIsoprenoid metabolism in aphid : A new target for bioinsecticides development
Vandermoten, Sophie ULg; Charloteaux, Benoît ULg; Santini, Sébastien et al

Poster (2008, July)

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See detailAdaptive estimation algorithm for aircraft engine performance monitoring
Léonard, Olivier ULg; Borguet, Sébastien ULg; Dewallef, Pierre ULg

in Journal of Propulsion and Power (2008), 24(4), 763-769

In the frame of turbine engine performance monitoring, system identification procedures are often used to adapt a simulation model of the engine to some observed data through a set of so-called health ... [more ▼]

In the frame of turbine engine performance monitoring, system identification procedures are often used to adapt a simulation model of the engine to some observed data through a set of so-called health parameters. Doing so, the values of these health parameters are intended to represent the actual health condition of the engine. The Kalman filter has been widely used to achieve the identification procedure in real-time onboard applications. However, to achieve a proper filtering of the measurement noise, the health parameters are often assumed to vary in time relatively slowly, preventing any abrupt accidental events from being tracked effectively. This contribution presents a procedure called adaptive filtering. Based on a covariance-matching method, it is intended to automatically release the health parameters once an accidental event is detected. This enables the Kalman filter to deal with both continuous and abrupt fault conditions. [less ▲]

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See detailInduction of nuclear factor-kappaB and its downstream genes by TNF-alpha and IL-1beta has a pro-apoptotic role in pancreatic beta cells
Ortis, Fernanda; Pirot, P.; Naamane, N. et al

in Diabetologia (2008), 51

IL-1beta and TNF-alpha contribute to pancreatic beta cell death in type 1 diabetes. Both cytokines activate the transcription factor nuclear factor-kappaB (NF-kappaB), but recent observations suggest that ... [more ▼]

IL-1beta and TNF-alpha contribute to pancreatic beta cell death in type 1 diabetes. Both cytokines activate the transcription factor nuclear factor-kappaB (NF-kappaB), but recent observations suggest that NF-kappaB blockade prevents IL-1beta + IFN-gamma- but not TNF-alpha + IFN-gamma-induced beta cell apoptosis. The aim of the present study was to compare the effects of IL-1beta and TNF-alpha on cell death and the pattern of NF-kappaB activation and global gene expression in beta cells. METHODS: Cell viability was measured after exposure to IL-1beta or to TNF-alpha alone or in combination with IFN-gamma, and blockade of NF-kappaB activation or protein synthesis. INS-1E cells exposed to IL-1beta or TNF-alpha in time course experiments were used for IkappaB kinase (IKK) activation assay, detection of p65 NF-kappaB by immunocytochemistry, real-time RT-PCR and microarray analysis. RESULTS: Blocking NF-kappaB activation protected beta cells against IL-1beta + IFNgamma- or TNFalpha + IFNgamma-induced apoptosis. Blocking de novo protein synthesis did not increase TNF-alpha- or IL-1beta-induced beta cell death, in line with the observations that cytokines induced the expression of the anti-apoptotic genes A20, Iap-2 and Xiap to a similar extent. Microarray analysis of INS-1E cells treated with IL-1beta or TNF-alpha showed similar patterns of gene expression. IL-1beta, however, induced a higher rate of expression of NF-kappaB target genes putatively involved in beta cell dysfunction and death and a stronger activation of the IKK complex, leading to an earlier translocation of NF-kappaB to the nucleus. CONCLUSIONS/INTERPRETATION: NF-kappaB activation in beta cells has a pro-apoptotic role following exposure not only to IL-1beta but also to TNF-alpha. The more marked beta cell death induced by IL-1beta is explained at least in part by higher intensity NF-kappaB activation, leading to increased transcription of key target genes. [less ▲]

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See detailL'etude clinique du mois. Controle glycemique et morbimortalite cardio-vasculaire chez le patient diabetique de type 2. Resultats des etudes ACCORD, ADVANCE et VA-Diabetes.
Radermecker, Régis ULg; Philips, Jean-Christophe ULg; Jandrain, Bernard ULg et al

in Revue Médicale de Liège (2008), 63(7-8), 511-8

Type 2 diabetes is associated with a high risk of complications, essentially macrovascular events. Surprisingly, the effect of improved glucose control on coronary and cerebrovascular complications in ... [more ▼]

Type 2 diabetes is associated with a high risk of complications, essentially macrovascular events. Surprisingly, the effect of improved glucose control on coronary and cerebrovascular complications in this population remains questionable. Furthermore, the target level of glycated haemoglobin (HbA1c) to minimise the risk of diabetic complications is controversial. We report the results of three recent randomised control trials (ACCORD, ADVANCE, Veterans Affairs Diabetes), which assessed the impact on cardiovascular events of intensive glucose-lowering therapy. None of these studies was able to demonstrate a significant reduction of cardiovascular events in the intensive group as compared to the standard group. On the contrary, in ACCORD, the study with the most ambitious goal (HbA1c < 6%), the overall and cardiovascular mortality was greater in the intensive group. In contrast, in the ADVANCE trial, the mortality and the incidence of cardiovascular events were not statistically different between the two treatment groups, whereas the risk of microangiopathic complications, especially nephropathy, was significantly decreased in the intensive group (HbA1c < or = 6.5%, with modified release gliclazide as main treatment). Finally, VA-Diabetes showed that the effect of better glucose control on cardiovascular complications disappeared with duration of the disease and that the risk of cardiovascular events increased in patients with severe hypoglycaemic episodes. In the three studies, the hypoglycaemic risk was indeed increased in the intensive group, which may contribute to reduce the positive impact of better glucose control on cardiovascular complications. The best way to protect type 2 diabetic patients against coronary and cerebrovascular disease is to target all cardiovascular risk factors. [less ▲]

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