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See detail2D XFEM-based modeling of retraction and successive resections for preoperative image update.
Vigneron, Lara M.; Duflot, Marc P.; Robe, Pierre ULg et al

in Computer aided surgery : official journal of the International Society for Computer Aided Surgery (2009), 14(1-3), 1-20

This paper considers an approach to improving outcomes for neurosurgery patients by enhancing intraoperative navigation and guidance. Currently, intraoperative navigation systems do not accurately account ... [more ▼]

This paper considers an approach to improving outcomes for neurosurgery patients by enhancing intraoperative navigation and guidance. Currently, intraoperative navigation systems do not accurately account for brain shift or tissue resection. We describe how preoperative images can be incrementally updated to take into account any type of brain tissue deformation that may occur during surgery, and thus to improve the accuracy of image-guided navigation systems. For this purpose, we have developed a non-rigid image registration technique using a biomechanical model, which deforms based on the Finite Element Method (FEM). While the FEM has been used successfully for dealing with deformations such as brain shift, it has difficulty with tissue discontinuities. Here, we describe a novel application of the eXtended Finite Element Method (XFEM) in the field of image-guided surgery in order to model brain deformations that imply tissue discontinuities. In particular, this paper presents a detailed account of the use of XFEM for dealing with retraction and successive resections, and demonstrates the feasibility of the approach by considering 2D examples based on intraoperative MR images. To evaluate our results, we compute the modified Hausdorff distance between Canny edges extracted from images before and after registration. We show that this distance decreases after registration, and thus demonstrate that our approach improves alignment of intraoperative images. [less ▲]

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See detail2D-photochemical model for forbidden oxygen line emission for comet 1P/Halley
Cessateur, G.; De Keyser, J.; Maggiolo, R. et al

in Monthly Notices of the Royal Astronomical Society (2016)

We present here a 2D-model of photochemistry for computing the production and loss mechanisms of the O([SUP]1[/SUP]S) and O([SUP]1[/SUP]D) states, which are responsible for the emission lines at 577.7 nm ... [more ▼]

We present here a 2D-model of photochemistry for computing the production and loss mechanisms of the O([SUP]1[/SUP]S) and O([SUP]1[/SUP]D) states, which are responsible for the emission lines at 577.7 nm, 630 nm, and 636.4 nm, in case of the comet 1P/Halley. The presence of O[SUB]2[/SUB] within cometary atmospheres, measured by the in-situ ROSETTA and GIOTTO missions, necessitates a revision of the usual photochemical models. Indeed, the photodissociation of molecular oxygen also leads to a significant production of oxygen in excited electronic states. In order to correctly model the solar UV flux absorption, we consider here a 2D configuration. While the green to red-doublet ratio is not affected by the solar UV flux absorption, estimates of the red-doublet and green lines emissions are, however, overestimated by a factor of two in the 1D model compared to the 2D model. Considering a spherical symmetry, emission maps can be deduced from the 2D model in order to be directly compared to ground and/or in-situ observations. [less ▲]

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See detail2D-Vertical Model for Free Surface Incompressible Flows: Validation and Applications
Detrembleur, Sylvain; Dewals, Benjamin ULg; Pirotton, Michel ULg

in Proc. 34th IAHR World Congress - Balance and Uncertainty (2011)

Efficient design of hydraulic structures such as weirs and bottom outlets requires a detailed description of the complex turbulent flows occurring on these structures. Compared to laboratory experiments ... [more ▼]

Efficient design of hydraulic structures such as weirs and bottom outlets requires a detailed description of the complex turbulent flows occurring on these structures. Compared to laboratory experiments, numerical modeling offers more flexibility and cost-effectiveness to test different designs. The non-hydrostatic 2D-vertical model presented here solves the RANS equations for incompressible flows in the vertical plane. It is based on the projection method for pressure-velocity coupling, while free surface tracking is conducted by means of the level set technique and Sussman’s velocity extension algorithm. It enables to predict accurately the flow pattern in the vertical plane and deals with multiple interfaces (jets, drops…). The solver has been validated for both steady and unsteady free surface flows, based on theoretical and experimental data. The paper will detail the application of the model to a pressurized flow and to a sloshing tank. [less ▲]

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See detail2D1/2 Thermal-Mechanical Model of Continuous Casting of Steel Using Finite Element Method
Pascon, Frédéric ULg

Doctoral thesis (2002)

The thesis deals with a numerical model based on the finite element method applied to the continuous casting of steel. The model is developed using the LAGAMINE finite element code and two industrial ... [more ▼]

The thesis deals with a numerical model based on the finite element method applied to the continuous casting of steel. The model is developed using the LAGAMINE finite element code and two industrial applications of steel casting are presented to illustrate the capabilities of the model. The first chapter introduces the continuous casting process, defining the essential terminology and the industrial challenges. Then, the objectives of the model are detailed: the model is applied to the upper part of the caster (in the mould region) as well as to the bending and straightening zones. Chapters two, three and four are dedicated to the theoretical developments of thermal aspects (phase transformations, thermal contraction, heat flow and thermal boundary conditions), mechanical aspects (generalized plain strain state, material constitutive law, ferrostatic pressure and mechanical contact) and the staggered analysis used for thermal / mechanical coupling. In the two next chapters, some numerical results are presented. The model has been first applied to a 125mm square billet in the mould region. The industrial goal is to evaluate the effect of the mould taper on the cooling of the billet (temperature evolution, solid shell growing, stress and strain development). The second application focuses on the risk of transverse cracking during straightening of steel slabs and the effect of some local defects (reduction of secondary cooling, locking or misalignment of rolls). The thesis ends with some concluding remarks and perspectives for the model. [less ▲]

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See detail2D1/2 thermo-mechanical model of continuous casting using FEM
Pascon, Frédéric ULg; Habraken, Anne ULg

in Brucato, V. (Ed.) Proceedings of the 6th International ESAFORM Conference on Material Forming (2003)

Two complementary approaches of steel continuous casting modelling using the finite element code LAGAMINE have been developed in the M&S Department. The first one (at a macroscopic scale) describes the ... [more ▼]

Two complementary approaches of steel continuous casting modelling using the finite element code LAGAMINE have been developed in the M&S Department. The first one (at a macroscopic scale) describes the whole continuous casting process, from the free surface in the mould and through the entire machine, including thermal and mechanical behaviour of the steel. The second approach focuses on the prediction of cracks and is developed at grain scale. We present in this paper a description of the context in which the study started, the description of the macroscopic approach and some results. [less ▲]

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See detail2D–3D Conversion
Grogna, David ULg; Lejeune, Antoine ULg; Michel, Benoit

in Lucas, Laurent; Loscos, Celine; Remion, Yannick (Eds.) 3D Video: From Capture to Diffusion (2013)

Detailed reference viewed: 16 (1 ULg)
See detail2e campagne de fouille à Chagar Bazar (Syrie)
Tunca, Önhan ULg; McMahon, A.; Baghdo, Abd el-Massih

in Orient-Express 2000/4 (2000)

Detailed reference viewed: 43 (5 ULg)
See detail2ème Atelier Nitrate - Eau. Evaluation du Programme de Gestion Durable de l'Azote
Vandenberghe, Christophe ULg; Colinet, Gilles ULg; Destain, Jean-Pierre ULg et al

Book published by Presses Agronomiques de Gembloux (2013)

Under the four-year review of the program of action for the implementation of the Nitrates Directive in the Walloon region, a workshop was held a couple of scientists to assess the current program and to ... [more ▼]

Under the four-year review of the program of action for the implementation of the Nitrates Directive in the Walloon region, a workshop was held a couple of scientists to assess the current program and to propose ways of improvement [less ▲]

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See detail2ème BBM - ostéoporose
CAVALIER, Etienne ULg

Learning material (2011)

Detailed reference viewed: 33 (5 ULg)
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See detail2F3 Monoclonal Antibody Recognizes the O26 O-Antigen Moiety of the Lipopolysaccharide of Enterohemorrhagic Escherichia coli Strain 4276
Szalo, Ioan Mihai ULg; Taminiau, Bernard ULg; Goffaux, Frédéric et al

in Clinical and Diagnostic Laboratory Immunology (2004), 11(3), 532-537

Enterohemorrhagic Escherichia coli (EHEC) and enteropathogenic E. coli (EPEC) organisms are groups of pathogenic strains whose infections are characterized by a typical lesion of enterocyte attachment and ... [more ▼]

Enterohemorrhagic Escherichia coli (EHEC) and enteropathogenic E. coli (EPEC) organisms are groups of pathogenic strains whose infections are characterized by a typical lesion of enterocyte attachment and effacement. They are involved in enteric diseases both in humans and in animals, and EHEC strains can be responsible for hemolytic uremic syndrome in humans. Previously, it was shown that the 2F3 monoclonal antibody (MAb) is specific for the O26 EHEC and EPEC strains (P. Kerr, H. Ball, B. China, J. Mainil, D. Finlay, D. Pollock, I. Wilson, and D. Mackie, Clin. Diagn. Lab. Immunol. 6:610–614, 1999). As these groups of bacteria play an important role in pathology, the aim of this paper was to characterize the antigen recognized by the 2F3 MAb and its genetic determinant. A genomic locus containing the entire O-antigen gene cluster and half of the colanic acid gene cluster from an O26 EHEC strain was shown to be sufficient for the production of the antigen recognized by the 2F3 MAb in an E. coli DH5 strain. By transposon mutagenesis performed on the recombinant plasmid, all 2F3 enzyme-linked immunosorbent assay-negative mutants had their transposons inserted into the O-antigen gene cluster. The O-antigen gene cluster was also cloned from an O26 EHEC strain into the E. coli DH5 strain, which then produced a positive result with the 2F3 MAb. Further analysis of the type of lipopolysaccharides (smooth or rough) produced by the clones and mutants and of the O antigen of the 2F3-positive clones confirmed that the epitope recognized by the 2F3 MAb is located on the O antigen in the O26 EHEC and EPEC strains and that its genetic determinant is located inside the O-antigen gene cluster. [less ▲]

Detailed reference viewed: 58 (8 ULg)
See detail2nd International Conference, Architecture & Philosophy: AT THE TURN OF THE EXPERIENCE, questioning what we build, sharing what we face
YOUNES, Chris; BONNAUD, Xavier; Bodart, Céline ULg et al

Scientific conference (2016, March)

The conference is an initiative of the GERPHAU lab, research group for Philosophy, Architecture, Urban (Architecture School of Paris La Villette, UMR 7218 CNRS-Lavue), in partnership with Cité de l ... [more ▼]

The conference is an initiative of the GERPHAU lab, research group for Philosophy, Architecture, Urban (Architecture School of Paris La Villette, UMR 7218 CNRS-Lavue), in partnership with Cité de l'Architecture et du Patrimoine and philAU (a scientific thematic network : Philosophy, Architecture, Urban). This conference is also supported by ARENA(Architectural Research in Europe Network Association), a shared platform that aims to promote, support, develop and disseminate high-quality research in all fields of architecture in the widest sense. The proposal of the conference AT THE TURN OF THE EXPERIENCE is to start with the hypothesis that the architecture could be conceive as a way of enquiring on this new experience of the world. Because it provides precisely access to the experience modalities of the building world, we argue that it could in return reveal such a processing paradigm shift in the making of human settlements. We invite to re-invest and re-question its representation apparatus that it used to deploy on territories in order to translate in fictions and projects what these ones could become. To discuss about these apparatus just as such these possible translations, the conference is addressed to all researchers and practitioners, architects and creators, the experienced ones and the experiencing ones as well, whose works attempt to question what we build and to share what we face. [less ▲]

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See detailThe 2nd Workshop on Active Internet Measurements (AIMS-2) Report
claffy, kc; Aben, Emile; Auge, Jorge, et al

in Computer Communication Review (2010), 40(5), 53-58

On February 8-10, 2010, CAIDA hosted the second Work- shop on Active Internet Measurements (AIMS-2) as part of our series of Internet Statistics and Metrics Analysis (ISMA) workshops. The goals of this ... [more ▼]

On February 8-10, 2010, CAIDA hosted the second Work- shop on Active Internet Measurements (AIMS-2) as part of our series of Internet Statistics and Metrics Analysis (ISMA) workshops. The goals of this workshop were to further our understanding of the potential and limitations of active mea- surement research and infrastructure in the wide-area Inter- net, and to promote cooperative solutions and coordinated strategies to addressing future data needs of the network and security research communities. The three-day workshop included presentations, group discussion and analysis, and focused interaction between participating researchers, oper- ators, and policymakers from all over the world. This report describes the motivation and findings of the workshop, and reviews progress on recommendations developed at the 1st Active Internet Measurements Workshop in 2009 [18]. Slides from the workshop presentations are available at [9]. [less ▲]

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See detail3 ',4 ',5 ',6 ' tetradehydrolongicaudatine Y, an anhydronium base from Strychnos usambarensis
Frederich, Michel ULg; Quetin-Leclercq, J.; Biala, R. G. et al

in Phytochemistry (1998), 48(7), 1263-1266

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See detailThe 3' region of bovine leukemia virus genome encodes a trans-activator protein.
Rosen, C. A.; Sodroski, J. G.; Willems, Luc ULg et al

in EMBO Journal (1986), 5(10), 2585-9

The genome of bovine leukemia virus (BLV) contains several overlapping, long open reading frames 3' to the envelope gene. Experiments presented here show that the cDNA encompassing the X region open ... [more ▼]

The genome of bovine leukemia virus (BLV) contains several overlapping, long open reading frames 3' to the envelope gene. Experiments presented here show that the cDNA encompassing the X region open reading frames encodes a trans-activator function capable of increasing the level of gene expression directed by the BLV long terminal repeat sequences. This study provides further evidence of the structural and functional similarities of the bovine leukemia virus and the human T lymphotropic viruses, HTLV-I and HTLV-II. [less ▲]

Detailed reference viewed: 11 (3 ULg)