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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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See detailINVESTIGATION OF A LOCAL INDICATOR OF VOLTAGE EMERGENCY IN THE HELLENIC INTERCONNECTED SYSTEM
Vournas, Costas; Sakellaridis, N.; Christoforidis, George et al

(2008, July)

In this paper we evaluate the performance of a proposed local indicator of voltage emergency for a simulated unstable contingency of the Hellenic Intercon-nected System identified through the on-line VSA ... [more ▼]

In this paper we evaluate the performance of a proposed local indicator of voltage emergency for a simulated unstable contingency of the Hellenic Intercon-nected System identified through the on-line VSA applica-tion for the summer peak of 2007. The effect of deadbands and tap range limits in delaying the emergency alarm issued is examined. The area mostly affected by the insta-bility is identified through the proposed algorithm and a simple load-shedding scheme sufficient to avert the collapse is suggested. [less ▲]

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See detailPROSPECTS OF AN IMPROVED SYSTEM PROTECTION SCHEME AGAINST VOLTAGE INSTABILITY IN THE RTE SYSTEM
Capitanescu, Florin ULg; Otomega, Bogdan; Lefebvre, Hervé et al

(2008, July)

This paper reports on prospective tests of a system protection scheme against long-term voltage instability relying on a set of distributed controllers, each monitoring a transmission voltage, blocking ... [more ▼]

This paper reports on prospective tests of a system protection scheme against long-term voltage instability relying on a set of distributed controllers, each monitoring a transmission voltage, blocking tap changers and shedding loads in a zone. The emergency actions adjust in magnitude and location to the disturbance. Each controller acts in closed loop, which guarantees robustness. The method is illustrated on a real-life model of the Western region of the RTE system. The choice of the controller settings is discussed in some detail and examples of performance are given, combining the above remedial action with capacitor switching and secondary voltage control. [less ▲]

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See detailOn periodical oscillations of Lurie systems with discontinuous nonlinearity
Efimov, Denis ULg

in Proc. 17th IFAC WC, Seoul, Korea (2008)

Sufficient conditions of global attracting limit cycle existence for Lurie system with sign nonlinearity are presented. It is assumed that the linear part of the system is output stabilizable, the ... [more ▼]

Sufficient conditions of global attracting limit cycle existence for Lurie system with sign nonlinearity are presented. It is assumed that the linear part of the system is output stabilizable, the nonlinearity has linear negative term plus positive one proportional to the output sign. Conditions of oscillatority in the sense of Yakubovich for this class of systems are also reestablished. [less ▲]

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See detailEuropean association of echocardiography recommandations for standardization of performance, digital staorage and reporting of echocardiographic studies
Evangelista, A.; Flachskampf, F.; Lancellotti, Patrizio ULg et al

in European Journal of Echocardiography (2008), 9(4), 438-48

In view of the European Association of Echocardiography (EAE) mission statement “To promote excellence in clinical diagnosis, research, technical development, and education in cardiovascular ultrasound in ... [more ▼]

In view of the European Association of Echocardiography (EAE) mission statement “To promote excellence in clinical diagnosis, research, technical development, and education in cardiovascular ultrasound in Europe” and the increasing demand for standardization and quality control, the EAE have established recommendations and guidelines for standardization of echocardiography performance, data acquisition (images, measurements and morphologic descriptors), digital storage and reporting of echocardiographic studies. The aim of these recommendations is to provide a European consensus document on the minimum acceptable requirements for the clinical practice of echocardiography today and thus improve the quality and consistency of echocardiographic practice in Europe. [less ▲]

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See detailStress echocardiography expert consensus statement-executive summary: european association of echocardiography (a registrated branch of the ESC).
Sicari, R.; Nihoyannopoulos, P.; Evangelista, A. et al

in European Journal of Echocardiography (2008), 9(4), 415-37

In view of the European Association of Echocardiography (EAE) mission statement "To promote excellence in clinical diagnosis, research, technical development, and education in cardiovascular ultrasound in ... [more ▼]

In view of the European Association of Echocardiography (EAE) mission statement "To promote excellence in clinical diagnosis, research, technical development, and education in cardiovascular ultrasound in Europe" and the increasing demand for standardization and quality control, the EAE have established recommendations and guidelines for standardization of echocardiography performance, data acquisition (images, measurements and morphologic descriptors), digital storage and reporting of echocardiographic studies. The aim of these recommendations is to provide a European consensus document on the minimum acceptable requirements for the clinical practice of echocardiography today and thus improve the quality and consistency of echocardiographic practice in Europe. [less ▲]

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See detailCyclic appearance of left ventricular outflow tract dynamic obstruction during mechanical ventilation: evidence for a preload dependent phenomenon.
Canivet, Jean-Luc ULg; Lancellotti, Patrizio ULg; Radermecker, Marc ULg et al

in Journal of Intensive Care Medicine (2008), 23(4), 281-4

The cyclic appearance of dynamic left ventricular outflow tract obstruction during mechanical ventilation, according to the phasic changes in preload, is described in this article. Hemodialysis-induced ... [more ▼]

The cyclic appearance of dynamic left ventricular outflow tract obstruction during mechanical ventilation, according to the phasic changes in preload, is described in this article. Hemodialysis-induced fluid removal resulted in preload dependence as evidenced by the pulse pressure variation in a 56-year-old critically ill patient. The clinical picture was suggestive of myocardial failure. Transthoracic echocardiography disclosed dynamic left ventricular outflow tract obstruction associated with systolic anterior motion of the mitral valve. Progressive fluid restitution resulted in a parallel decrease in both the degree of dynamic obstruction and pulse pressure variation. During fluid loading, dynamic obstruction disappeared at first during the inspiratory phase of intermittent positive pressure ventilation corresponding to the phasic increase in left ventricular preload. Further fluid loading resulted in the disappearance of dynamic obstruction during both inspiratory and expiratory phase of intermittent positive pressure ventilation. This is the first reported case clearly relating left ventricular outflow tract dynamic obstruction to preload dependence during mechanical ventilation in a critically ill patient without predisposing anatomical factor. [less ▲]

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See detailThe development and applications of a ground-based fiber nulling coronagraph
Martin, Stefan; Serabyn, Eugene; Liewer, Kurt et al

in Optical and Infrared Interferometry (2008, July)

Detailed reference viewed: 36 (3 ULg)