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See detailEfficiency of haplotype-based methods to fine-map QTLs and embryonic lethal variants affecting fertility: Illustration with a deletion segregating in Nordic Red cattle
Kadri, Naveen Kumar ULg; Sahana, Goutam; Guldbrandtsen, Bernt et al

in Livestock Science (2014), 166

Despite its importance, fertility has been declining in many cattle populations. In dairy cattle, this decline is often attributed to the negative correlation between fertility and productions traits ... [more ▼]

Despite its importance, fertility has been declining in many cattle populations. In dairy cattle, this decline is often attributed to the negative correlation between fertility and productions traits. Recent studies showed that embryonic lethal variants might also account for a non-negligible fraction of the fertility decline. Therefore identification of such embryonic lethal variants is essential to improve fertility. We herein illustrate, with an example of a large recessive lethal deletion recently identified in Nordic Red cattle, that haplotype-based method are particularly efficient to identify such embryonic lethal variants. We first show that haplotypes can be used in traditional QTL mapping approaches and that they present very high linkage disequilibrium with underlying variants. Haplotypes can also be used in scan for lack of homozygosity. Indeed,if a haplotype is associated to a recessive lethal variant, significantly fewer living individuals will be homozygote for that haplotype than expected. For both approaches, haplotype- based methods were particularly efficient. The lack of homozygosity approach achieved higher significance than the QTL approach. Only frequent variants can be detected with both approaches unless huge genotyped cohorts are available. An alternative approach would rely on identifying potential harmful variants in next-generation sequencing data followed by the genotyping of a larger population for these variants. [less ▲]

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See detailThe Efficiency of In vitro Ovine Embryo Production Using an Undefined or a Defined Maturation Medium is Determined by the Source of the Oocyte.
Cocero, M.; Alabart, J.; Hammami, S. et al

in Reproduction in Domestic Animals (2011), 46(3), 463-470

In vitro oocyte maturation can be influenced by oocyte source and maturation media composition. The aim of the present study was to compare the efficiency of a defined in vitro maturation medium (TCM199 ... [more ▼]

In vitro oocyte maturation can be influenced by oocyte source and maturation media composition. The aim of the present study was to compare the efficiency of a defined in vitro maturation medium (TCM199 supplemented with cysteamine and epidermal growth factor; Cys + EGF) with an undefined medium (TCM199 supplemented with follicle-stimulating hormone and follicular fluid; FSH + FF) for in vitro production (IVP) of ovine embryos, using oocytes obtained by laparoscopic ovum pick-up from FSH-stimulated [n = 11; 158 cumulus-oocyte complexes (COCs)] and non-stimulated (n = 16; 120 COCs) live ewes, as well as abattoir-derived oocytes (170 COCs). The produced blastocysts were vitrified and some of them were transferred to synchronized recipients. The best and the worst final yields of embryo IVP observed in this study were obtained using oocytes from FSH-stimulated ewes matured in FSH + FF (41.3%; 33/80) and in Cys + EGF (19.2%; 15/78) medium, respectively (p < 0.01). No significant differences between both media were attained in the blastocyst development rate or in the final yield of embryo IVP using oocytes from non-stimulated ewes or abattoir-derived oocytes. The overall in vivo survival rate of the transferred vitrified blastocysts was 13.1% (8/61), without significant differences between oocyte sources or maturation media. In conclusion, under the experimental conditions of the present study, TCM199 supplemented with cysteamine and EGF is a convenient defined maturation medium for IVP of embryos from oocytes of live non-stimulated ewes or from oocytes of abattoir-derived ovaries. However, the best final yield of embryo IVP observed in this study was attained when oocytes came from FSH-stimulated donors and TCM199 was supplemented with FSH and follicular fluid [less ▲]

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See detailEfficiency of inventory plot patterns in quantitative analysis of vegetation : a case study of tropical woodland and dense forest in Benin
Salako, Valère K.; Glele Kakai, Romain L.; Assogbadjo, Achille E. et al

in Southern Forests : a Journal of Forest Science (2013), 75(3), 137-143

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See detailEfficiency of pheromone-based formulations against phytophagous pests
Fassotte, Bérénice ULg; Vandereycken, Axel ULg; Chevalier Mendes Lopes, Thomas ULg et al

Conference (2015, May 19)

Innovative integrated pest management methods are needed to overcome market withdrawal of synthetic pesticides. Therefore, the identification of environment-friendly bio-products carrying direct or ... [more ▼]

Innovative integrated pest management methods are needed to overcome market withdrawal of synthetic pesticides. Therefore, the identification of environment-friendly bio-products carrying direct or indirect biocide activity is one promising alternative option. Our researches focus on the identification of appropriate formulations releasing volatile organic compounds that are attractant for natural enemies of insect pests. However, the elaboration of slow-release devices that ensure stable and controlled release of active volatile compounds is quite challenging. Here, we developed a formulation based on E-β-farnesene and (-)-β-caryophyllene, these two semiochemicals having strong attractive potential on aphid natural enemies including lady beetles and hoverflies. Both compounds were encapsulated together in alginate gel beads. The blend efficiency was first evaluated through laboratory assays, and then in wheat and broad bean fields, by considering the abundance and diversity of aphids and their natural enemies. [less ▲]

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See detailEfficiency of shaft sealing for CO2 sequestration in coal mines
Bertrand, François ULg; Charlier, Robert ULg; Collin, Frédéric ULg et al

in International Workshop on Geomechanics and Energy: The Ground as Energy Source and Storage (2015, October 13)

This work examined the efficiency of a shaft sealing system for the CO2 sequestration in abandoned coal mines. The particular case of the coal mine of Anderlues was considered. The performed simulation ... [more ▼]

This work examined the efficiency of a shaft sealing system for the CO2 sequestration in abandoned coal mines. The particular case of the coal mine of Anderlues was considered. The performed simulation took into account the anisotropic behaviour of shale and the presence of coalbeds. [less ▲]

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See detailEfficiency of sieving or classification for dry fractionation of aot mills and beta-glucans enrichment.
Roiseux, Olivier; Vanderbeke, E.; Blecker, Christophe ULg et al

Poster (2008, June)

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See detailEfficiency of T Cell Triggering by Anti-Cd3 Monoclonal Antibodies (Mab) with Potential Usefulness in Bispecific Mab Generation
Jacobs, Nathalie ULg; Mazzoni, A.; Mezzanzanica, D. et al

in Cancer Immunology, Immunotherapy (1997), 44(5), 257-64

T cell triggering can be achieved by monoclonal antibodies (mAbs) specific for the CD3/TcR complex. In the presence of appropriate costimulation and/or progression factors, such triggering permits the ... [more ▼]

T cell triggering can be achieved by monoclonal antibodies (mAbs) specific for the CD3/TcR complex. In the presence of appropriate costimulation and/or progression factors, such triggering permits the generation of effector cells for immunotherapy protocols involving the redirection of T cell lysis against tumor cells by mAbs bispecific for anti-CD3/anti-tumor cells (bs-mAbs). Focusing our analysis on the clinically relevant bs-mAb OC/TR, we found that bs-mAbs generated with the same anti tumor specificity, but two other anti-CD3 mAbs, TR66 and OKT3, have the same and a significantly lower lytic potential, respectively, compared with that of OC/TR. To evaluate the relevance of the anti-CD3 component, we examined several anti-CD3 mAbs with respect to binding parameters and the ability to trigger T lymphocytes. Competitive binding assays suggested that all anti-CD3 mAbs recognized the same or overlapping epitopes, although mAbs BMA030 and OC/TR bound with lower avidity than did alpha CD3 (the bivalent anti-CD3 mAb produced by the hybrid hybridoma OC/TR). TR66 and OKT3, as determined by measurement of the affinity constants. In all lymphocyte populations examined, which included resting peripheral blood mononuclear cells (PBMC), activated PBMC and T cell clones, OKT3, BMA033 and OC/TR failed to mobilize Ca2+ without cross-linking, whereas alpha CD3, in both murine and murine-human chimeric versions, TR66 and BMA030, did not require cross-linking. The ability to induce CD3 modulation was associated in part with the induction of Ca2+ fluxes. Despite the differences in the behavior of these mAbs in triggering the events that precede proliferation, all of them ultimately led to expression of the IL-2 receptor and to proliferation in T cells in the presence of accessory cells. Our data suggest that anti-CD3 mAbs that bind more rapidly (strong Ca2+ mobilizers) and more tightly under physiological conditions are good candidates for retargeting T cells in the bs-mAb clinical application. [less ▲]

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See detailEfficiency of Targeted Energy Transfers in Coupled Nonlinear Oscillators Associated with 1:1 Resonance Captures
Sapsis, T.; Vakakis, Alexander F.; Gendelman, O. V. et al

in 45th Technical Meeting of the Society of Engineering Science, Urbana Champaign, 2008 (2008)

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See detailEfficiency of targeted energy transfers in coupled nonlinear oscillators associated with 1:1 resonance captures:Part II, analytical study
Sapsis, T. P.; Vakakis, Alexander F.; Gendelman, O. V. et al

in Journal of Sound & Vibration (2009)

We study targeted energy transfer in a two degree-of-freedom damped system under the conditionof1:1transient resonance capture. The system consists of a linear oscillator strongly coupled to an ... [more ▼]

We study targeted energy transfer in a two degree-of-freedom damped system under the conditionof1:1transient resonance capture. The system consists of a linear oscillator strongly coupled to an essentially nonlinear attachment or nonlinear energy sink. In a companion paper[ Quinnetal., Efficiency of targeted energy transfers in coupled nonlinear oscillators associated with1:1resonance captures: part I, Journal of Sound and Vibration 311 (2008)1228–1248]we studied the under lying structure of the Hamiltonian dynamics of this system ,and showed that for sufficiently small values of viscous damping , nonlinear damped transitions are strongly influenced by the under lying topological structure of periodic and quasi periodic or bits of the Hamiltonian system. In this work direct analytical treatment of the governing strongly nonlinear damped equations of motion is performed through slow/fast partitions of the transient responses, in order to investigate analytically the parameter region of optimal targeted energy transfer .To this end, we determine the characteristic time scales of the dynamics that influence the capacity of the nonlinear attachment to passively absorb and locally dissipate broad band energy from the linear oscillator. Then, we prove that optimal targeted energy transfer is realized for initial energies close to the neighbourhood of a homo clinic or bit of the under lying Hamiltonian system. We study analytically transient orbits resulting as perturbations of the homo clinic or bit in the weak lydamped system, and show that this yields an additional slow-time scale in the averaged dynamics, and leads to optimal targeted energy transfer from the linear oscillator to the nonlinear energy sink in a single ‘‘super-slow’’ half-cycle. We show that at higher energies, this ‘‘super-slow’’ half-cycle is replaced by strong nonlinear beats, which lead to significant but suboptimal targeted energy transfer efficiency. Finally, we investigate numerically targeted energy transfer efficiency in this system over a wide range of system parameter sand verify the analytical predictions. 2009 Elsevier Ltd .All rights reserved. [less ▲]

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See detailEfficiency of TET in coupled oscillators associated with 1: resonance: Part 1
Quinn, D. Dane; Gendelman, Oleg; Kerschen, Gaëtan ULg et al

in Journal of Sound & Vibration (2008), 311

We study targeted energy transfers and nonlinear transitions in the damped dynamics of a two degree-of-freedom system of coupled oscillators (a linear oscillator with a lightweight, essentially nonlinear ... [more ▼]

We study targeted energy transfers and nonlinear transitions in the damped dynamics of a two degree-of-freedom system of coupled oscillators (a linear oscillator with a lightweight, essentially nonlinear, ungrounded attachment), caused by 1:1 resonance captures of the dynamics. Part I of this work deals with the underlying structure of the Hamiltonian dynamics of the system, and demonstrates that, for sufficiently small values of viscous damping, the damped transitions are strongly influenced by the underlying topological structure of periodic and quasiperiodic orbits of the corresponding Hamiltonian system. Focusing exclusively on 1:1 resonance captures in the system, it is shown that the topology of these damped transitions affect drastically the efficiency of passive energy transfer from the linear system to the nonlinear attachment. Then, a detailed computational study of the different types of nonlinear transitions that occur in the weakly damped system is presented, together with an analytical treatment of the nonlinear stability of certain families of periodic solutions of the underlying Hamiltonian system that strongly influence the said transitions. As a result of these studies, conditions on the system and forcing parameters that lead to effective or even optimal energy transfer from the linear system to the nonlinear attachment are determined. In Part II of this work, direct analytical treatment of the governing strongly nonlinear damped equations of motion is performed, in order to analytically model the dynamics in the region of optimal energy transfer, and to determine 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. r 2007 Elsevier Ltd. All rights reserved [less ▲]

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See detailEfficiency of the sec-butyllithium/m-diisopropylbenzene diadduct as an anionic polymerization initiator in apolar solvents
Yu, Y. S.; Jérôme, Robert ULg; Fayt, Roger et al

in Macromolecules (1994), 27(21), 5957-5963

The 2/1 sec-butyllithium/1,3-diisopropenylbenzene adduct has been prepared and evaluated as an effective, hydrocarbon soluble, difunctional initiator for the synthesis of polystyrene-polybutadiene ... [more ▼]

The 2/1 sec-butyllithium/1,3-diisopropenylbenzene adduct has been prepared and evaluated as an effective, hydrocarbon soluble, difunctional initiator for the synthesis of polystyrene-polybutadiene-polystryene (SBS) thermoplastic elastomers in cyclohexane or benzene solution. The molecular weight distribution of both the PBD central block and the final block copolymer is narrow,and the expected molecular weight is obtained. However, mechanical testing, degradation of the PBD component, and use of an excess of s-BuLi compared to DIB suggest that the final copolymers are diblock instead of triblock as expected. The stoichiometric reaction of s-BuLi with DIB in an apolar solvent essentially results in the expected Li diadduct. This organolithium compound does not however react as a difunctional anionic initiator in a hydrocarbon solvent, but rather as a monofunctional compound more likely due to an association process. Addition of enough THF can make approximately two species active per DIB molecule. The addition of small amounts of triethylamine (<10 molecules per organolithium site) does not contribute to the formation of an acceptable difunctional initiator. The 1/1 addition of lithium tert-butoxide to the Li diadduct of DIB does not perturb the 1,4-microstructure of PBD, but it does not promote the activity of each metalated site of the initiator. [less ▲]

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See detailEfficiency of various nitrones used as precursors of nitroxides in radical polymerization of styrene
Sciannamea, Valérie; Detrembleur, Christophe ULg; Claes, Michaël et al

Poster (2003, May 16)

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See detailAn efficient 3D implicit approach for the thermomechanical simulation of elastic–viscoplastic materials submitted to high strain rate and damage
Jeunechamps, Pierre-Paul; Ponthot, Jean-Philippe ULg

in International Journal for Numerical Methods in Engineering (2013), 94

This paper aims at presenting a general consistent numerical formulation able to take into account, in a coupled way, strain rate, thermal and damage effects on the behavior of materials submitted to ... [more ▼]

This paper aims at presenting a general consistent numerical formulation able to take into account, in a coupled way, strain rate, thermal and damage effects on the behavior of materials submitted to quasistatic or dynamic loading conditions in a large deformation context. The main features of this algorithmic treatment are as follows: -A unified treatment for the analysis and implicit time integration of thermo-elasto-viscoplastic constitutive equations including damage that depends on the strain rate for dynamic loading conditions. This formalism enables us to use dynamic thermomechanically coupled damage laws in an implicit framework. -An implicit framework developed for time integration of the equations of motion. An efficient staggered solution procedure has been elaborated and implemented so that the inertia and heat conduction effects can be properly treated. - An operator split-based implementation, accompanied by a unified method to analytically evaluate the consistent tangent operator for the (implicit) coupled damage–thermo-elasto-viscoplastic problem. -The possibility to couple any hardening law, including rate-dependent models, with any damage model that fits into the present framework. All the developments have been considered in the framework of an implicit finite element code adapted to large strain problems. The numerical model will be illustrated by several applications issued from the impact andmetal-forming domains. All these physical phenomena have been included into an oriented object finite element code (implemented at LTAS-MN2L, University of Liège, Belgium) named Metafor. [less ▲]

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See detailEfficient 3D transfer operators based on numerical integration
Bussetta, Philippe ULg; Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in International Journal for Numerical Methods in Engineering (2015), 102(3-4), 892-929

This paper deals with data transfer between two meshes as it happens in a finite element context when a remeshing has to be performed. We propose a finite-volume-based data transfer method for an ... [more ▼]

This paper deals with data transfer between two meshes as it happens in a finite element context when a remeshing has to be performed. We propose a finite-volume-based data transfer method for an efficient remeshing of three-dimensional solid mechanics problems. The originality of this transfer method stems from a linear reconstruction of the fields to be transferred on an auxiliary finite volume mesh, a fast computation of the transfer operator and the application to the complete remeshing of 3D problems. This procedure is applicable to both nodal values and discrete fields defined at quadrature points. In addition, a data transfer method using mortar elements is presented. The main improvement made to this second method comes from a fast computation of mortar elements. These two data transfer methods are compared with the simplest transfer method, which consists of a classical interpolation. After some academic examples, we present 2D forging and 3D friction stir welding applications. [less ▲]

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See detailEfficient access pricing and endogenous market structure
Gautier, Axel ULg

Poster (2010, May)

We investigate how a regulatory mechanism can influence the nature of competition in a network industry. In the downstream market, the seller of a differentiated retail product competes with an incumbent ... [more ▼]

We investigate how a regulatory mechanism can influence the nature of competition in a network industry. In the downstream market, the seller of a differentiated retail product competes with an incumbent firm. The incumbent firm is also the owner of the essential input. The regulator may or may not observe the cost of the entrant. To maximize social welfare the regulator specifies the access charge that the entrant must pay to the incumbent, and the retail prices. The optimal access charge is a uniform price that respects the criteria of transparency and non-discrimination that are imposed by the competition and regulation directives in most countries. We derive new formulas for retail and access prices adhering to the traditional Ramsey rule. Since the competing firm takes the decision to enter following the choice of the regulatory regime, the nature of the retail market competition is endogenous [less ▲]

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See detailEfficient ALE mesh management for 3D quasi-Eulerian problems
Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in International Journal for Numerical Methods in Engineering (2012), 92(10), 857-890

In computational solid mechanics, the ALE formalism can be very useful to reduce the size of finite element models of continuous forming operations such as roll forming. The mesh of these ALE models is ... [more ▼]

In computational solid mechanics, the ALE formalism can be very useful to reduce the size of finite element models of continuous forming operations such as roll forming. The mesh of these ALE models is said to be quasi-Eulerian because the nodes remain almost fixed—or almost Eulerian—in the main process direction, although they are required to move in the orthogonal plane in order to follow the lateral displacements of the solid. This paper extensively presents a complete node relocation procedure dedicated to such ALE models. The discussion focusses on quadrangular and hexahedral meshes with local refinements. The main concern of this work is the preservation of the geometrical features and the shape of the free boundaries of the mesh. With this aim in view, each type of nodes (corner, edge, surface and volume) is treated sequentially with dedicated algorithms. A special care is given to highly curved 3D surfaces for which a CPU-efficient smoothing technique is proposed. This new method relies on a spline surface reconstruction, on a very fast weighted Laplacian smoother with original weights and on a robust reprojection algorithm. The overall consistency of this mesh management procedure is finally demonstrated in two numerical applications. The first one is a 2D ALE simulation of a drawbead, which provides similar results to an equivalent Lagrangian model yet is much faster. The second application is a 3D industrial ALE model of a 16-stand roll forming line. In this case, all attempts to perform the same simulation by using the Lagrangian formalism have been unsuccessful. [less ▲]

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See detailAn efficient algorithm for the provision of a day-ahead modulation service by a load aggregator
Mathieu, Sébastien ULg; Ernst, Damien ULg; Louveaux, Quentin ULg

in Proceedings of the 4th European Innovative Smart Grid Technologies (ISGT) (2013, October)

This article studies a decision making problem faced by an aggregator willing to offer a load modulation service to a Transmission System Operator. This service is contracted one day ahead and consists in ... [more ▼]

This article studies a decision making problem faced by an aggregator willing to offer a load modulation service to a Transmission System Operator. This service is contracted one day ahead and consists in a load modulation option, which can be called once per day. The option specifies the range of a potential modification on the demand of the loads within a certain time interval. The specific case where the loads can be modeled by a generic tank model is considered. Under this assumption, the problem of maximizing the range of the load modulation service can be formulated as a mixed integer linear programming problem. A novel heuristic-method is proposed to solve this problem in a computationally efficient manner. This method is tested on a set of problems. The results show that this approach can be orders of magnitude faster than CPLEX without significantly degrading the solution accuracy. [less ▲]

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See detailAn efficient algorithm to perform multiple testing in epistasis screening
Van Lishout, François ULg; Mahachie John, Jestinah ULg; Gusareva, Elena ULg et al

in BMC Bioinformatics (2013), 14

Background: Research in epistasis or gene-gene interaction detection for human complex traits has grown over the last few years. It has been marked by promising methodological developments, improved ... [more ▼]

Background: Research in epistasis or gene-gene interaction detection for human complex traits has grown over the last few years. It has been marked by promising methodological developments, improved translation efforts of statistical epistasis to biological epistasis and attempts to integrate different omics information sources into the epistasis screening to enhance power. The quest for gene-gene interactions poses severe multiple-testing problems. In this context, the maxT algorithm is one technique to control the false-positive rate. However, the memory needed by this algorithm rises linearly with the amount of hypothesis tests. Gene-gene interaction studies will require a memory proportional to the squared number of SNPs. A genome-wide epistasis search would therefore require terabytes of memory. Hence, cache problems are likely to occur, increasing the computation time. In this work we present a new version of maxT, requiring an amount of memory independent from the number of genetic effects to be investigated. This algorithm was implemented in C++ in our epistasis screening software MBMDR-3.0.3. We evaluate the new implementation in terms of memory efficiency and speed using simulated data. The software is illustrated on real-life data for Crohn's disease. Results: In the case of a binary (affected/unaffected) trait, the parallel workflow of MBMDR-3.0.3 analyzes all gene-gene interactions with a dataset of 100,000 SNPs typed on 1000 individuals within 4 days and 9 hours, using 999 permutations of the trait to assess statistical significance, on a cluster composed of 10 blades, containing each four Quad-Core AMD Opteron Processor 2352 2.1 GHz. In the case of a continuous trait, a similar run takes 9 days. Our program found 14 SNP-SNP interactions with a multiple-testing corrected p-value of less than 0.05 on real-life Crohn's disease data. Conclusions: Our software is the first implementation of the MB-MDR methodology able to solve large-scale SNP-SNP interactions problems within a few days, without using much memory, while adequately controlling the type I error rates. A new implementation to reach genome-wide epistasis screening is under construction. In the context of Crohn's disease, MBMDR-3.0.3 could identify epistasis involving regions that are well known in the field and could be explained from a biological point of view. This demonstrates the power of our software to find relevant phenotype-genotype higher-order associations. [less ▲]

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See detailAn Efficient Algorithm to Perform Multiple Testing in Epistasis Screening
Van Lishout, François ULg; Cattaert, Tom ULg; Mahachie John, Jestinah ULg et al

Conference (2011, December 13)

Background: Research in epistasis or gene-gene interaction detection for human complex traits has grown exponentially over the last few years. It has been marked by promising methodological developments ... [more ▼]

Background: Research in epistasis or gene-gene interaction detection for human complex traits has grown exponentially over the last few years. It has been marked by promising methodological developments, improved translation efforts of statistical epistasis to biological epistasis and attempts to integrate different omics information sources into the epistasis screening to enhance power. The quest for gene-gene interactions poses severe multiple-testing problems. In this context, the maxT algorithm is one technique to control the false-positive rate. However, the memory needed by this algorithm rises linearly with the amount of hypothesis tests. In main-effects detection, this is not a problem since the memory required is thus proportional to the number of SNPs. In contrast, gene-gene interaction studies will require a memory proportional to the squared amount of SNPs. A genome wide epistasis would therefore require terabytes of memory. Hence, cache problems are likely to occur, increasing the computation time. Methods: In this work we present a new version of maxT, requiring an amount of memory independent from the number of genetic effects to be investigated. This algorithm was implemented in C++ in our epistasis screening software MB-MDR-2.6.2 and compared to MB-MDR's first implementation as an R-package (Calle et al., Bioinformatics 2010). We evaluate the new implementation in terms of memory efficiency and speed using simulated data. The software is illustrated on real-life data for Crohn's disease. Results: The sequential version of MBMDR-2.6.2 is approximately 5,500 times faster than its R counterparts. The parallel version (tested on a cluster composed of 14 blades, containing each 4 quad-cores Intel Xeon CPU E5520@2.27 GHz) is approximately 900,000 times faster than the latter, for results of the same quality on the simulated data. It analyses all gene-gene interactions of a dataset of 100,000 SNPs typed on 1000 individuals within 4 days. Our program found 14 SNP-SNP interactions with a p-value less than 0.05 on the real-life Crohn’s disease data. Conclusions: Our software is able to solve large-scale SNP-SNP interactions problems within a few days, without using much memory. A new implementation to reach genome wide epistasis screening is under construction. In the context of Crohn's disease, MBMDR-2.6.2 found signal in regions well known in the field and our results could be explained from a biological point of view. This demonstrates the power of our software to find relevant phenotype-genotype associations. [less ▲]

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See detailEfficient algorithmic approach for mixed lubrication in cold rolling
STEPHANY, A.; Ponthot, Jean-Philippe ULg; COLLETTE, C. et al

in Proceedings of AMPT 2003, Advances in Materials and Processing Technologies (2003)

Detailed reference viewed: 7 (1 ULg)