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See detailA mortar algorithm combined with an Augmented Lagrangian approach for treatment of frictional contact problems
Cavalieri, Federico J.; Bruls, Olivier ULg; Cardona, Alberto

Conference (2013, July)

Contact mechanics is present in a wide range of mechanical engineering applications, and numerous works have been dedicated to the numerical solution of contact problems. Mathematically, the frictional ... [more ▼]

Contact mechanics is present in a wide range of mechanical engineering applications, and numerous works have been dedicated to the numerical solution of contact problems. Mathematically, the frictional contact problem can be seen as defined by a variational inequality. The solution corresponds to the minimum of the total energy of the system, subjected to inequalities constraints associated to the normal and tangential components of the traction and distance vectors, respectively. Nonlinear contact mechanics can be related to nonlinear optimization problems formulated by using the method of Lagrange multipliers, resulting in a saddle point system to be solved at each iteration. The method of Lagrange multipliers is very popular in contact mechanics because it overcomes the ill-conditioning inconvenience of the penalty methods. However, the size of the global matrix increases due to the additional unknowns (the Lagrange multipliers) and zero entries appear on the main diagonal of the stiffness matrix. These drawbacks can be avoided by using an augmented Lagrangian method, which consists in a combination of both the penalty and the Lagrange multipliers techniques. In this work, a mixed penalty-duality formulation based on an augmented Lagrangian approach for treating the contact and the friction inequality constraints is presented. The augmented Lagrangian approach allows to regularize the non differentiable contact terms, giving a C1 differentiable saddle-point function. The relative displacement of the contacting bodies is described in the framework of the Finite Element Method (FEM) using the mortar method, which gives a smooth representation of the contact forces across the bodies interface. [less ▲]

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See detailA mortar method combined with an augmented Lagrangian approach for treatment of mechanical contact problems
Cavalieri, Federico J.; Bruls, Olivier ULg; Cardona, Alberto

in Terze, Zdravko (Ed.) Multibody Dynamics: Computational Methods and Applications (2015)

This work presents a mixed penalty-duality formulation from an augmented Lagrangian approach for treating the contact inequality constraints. The augmented Lagrangian approach allows to regularize the non ... [more ▼]

This work presents a mixed penalty-duality formulation from an augmented Lagrangian approach for treating the contact inequality constraints. The augmented Lagrangian approach allows to regularize the non differentiable contact terms and gives a C1 differentiable saddle-point functional. The relative displacement of two contacting bodies is described in the framework of the Finite Element Method (FEM) using the mortar method, which gives a smooth representation of the contact forces across the bodies interface. To study the robustness and performance of the proposed algorithm, validation numerical examples with finite deformations and large slip motion are presented. [less ▲]

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See detailMortierella wolfii-Associated Invasive Disease.
LAYIOS, Nathalie ULg; Canivet, Jean-Luc; Baron, Frédéric ULg et al

in Emerging infectious diseases (2014), 20(9), 1591-2

Detailed reference viewed: 16 (7 ULg)
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See detailMorton Marcus, Pursuing the Dream Bone
Delville, Michel ULg

in Sentence: A Journal of Prose Poetics (2008), 7

Detailed reference viewed: 13 (0 ULg)
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See detailMosaic subclinical melanoderma and skin cancers.
Quatresooz, Pascale ULg

Conference (2007)

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See detailMosaic subclinical melanoderma: an Achilles heel for UV-related epidermal carcinogenesis?
Quatresooz, Pascale ULg; Petit, Ludivine; Uhoda, Isabelle et al

in International Journal of Oncology (2004), 25(6), 1763-7

Cutaneous cancers are not uncommon on the face of elderly patients. Melanin should protect, at least in part, against the ultraviolet (UV)-induced neoplastic damage. However, the density in melanin ... [more ▼]

Cutaneous cancers are not uncommon on the face of elderly patients. Melanin should protect, at least in part, against the ultraviolet (UV)-induced neoplastic damage. However, the density in melanin chromatophores is heterogeneous in the epidermis of Caucasian adults. The computerized UV light-enhanced visualization (ULEV) method is a sensitive tool to assess non-invasively this mosaic pattern of intra-epidermal melanin load. In this study, the combination of ULEV pattern analysis and image analysis were performed involving four groups of phototype III Caucasian subjects. The first group was composed of 55 patients aged from 65 to 75 years who suffered from several malignancies of facial skin. The second control group of 55 patients who never had developed skin cancers were matched with the first group for age, sex and phototype. The third group was composed of 80 patients aged from 49 to 59 years who had developed a single basal cell carcinoma. The fourth group comprised 80 age, sex and phototype-matched healthy control subjects. Irrespective of the groups of subjects, a correlation was found between the pattern grading and the objectively determined relative area of subclinical melanoderma. Patients with multiple skin cancers differed from the other groups by the fact that a significantly higher proportion of them exhibited an extensive type of subclinical melanoderma. This feature was also seen in a minority of patients with a single basal cell carcinoma. The extensive subclinical melanoderma pattern is interpreted as a clue for risk, but not as a cause of UV-induced skin carcinogenesis. [less ▲]

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See detailMOSAIC: a multiscale model of osteogenesis and sprouting angiogenesis with lateral inhibition of endothelial cells.
Carlier, Aurélie ULg; Geris, Liesbet ULg; Bentley, Katie et al

in PLoS Computational Biology (2012), 8(10), 1002724

The healing of a fracture depends largely on the development of a new blood vessel network (angiogenesis) in the callus. During angiogenesis tip cells lead the developing sprout in response to ... [more ▼]

The healing of a fracture depends largely on the development of a new blood vessel network (angiogenesis) in the callus. During angiogenesis tip cells lead the developing sprout in response to extracellular signals, amongst which vascular endothelial growth factor (VEGF) is critical. In order to ensure a correct development of the vasculature, the balance between stalk and tip cell phenotypes must be tightly controlled, which is primarily achieved by the Dll4-Notch1 signaling pathway. This study presents a novel multiscale model of osteogenesis and sprouting angiogenesis, incorporating lateral inhibition of endothelial cells (further denoted MOSAIC model) through Dll4-Notch1 signaling, and applies it to fracture healing. The MOSAIC model correctly predicted the bone regeneration process and recapitulated many experimentally observed aspects of tip cell selection: the salt and pepper pattern seen for cell fates, an increased tip cell density due to the loss of Dll4 and an excessive number of tip cells in high VEGF environments. When VEGF concentration was even further increased, the MOSAIC model predicted the absence of a vascular network and fracture healing, thereby leading to a non-union, which is a direct consequence of the mutual inhibition of neighboring cells through Dll4-Notch1 signaling. This result was not retrieved for a more phenomenological model that only considers extracellular signals for tip cell migration, which illustrates the importance of implementing the actual signaling pathway rather than phenomenological rules. Finally, the MOSAIC model demonstrated the importance of a proper criterion for tip cell selection and the need for experimental data to further explore this. In conclusion, this study demonstrates that the MOSAIC model creates enhanced capabilities for investigating the influence of molecular mechanisms on angiogenesis and its relation to bone formation in a more mechanistic way and across different time and spatial scales. [less ▲]

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See detailMosaicism of 46,Xx/47,Xx,+9/47,Xx,+?Mar in the Same Amniotic Fluid with Apparent Loss of One Cell Line after Delivery
Herens, Christian ULg; Pierquin, Geneviève ULg; Verloes, Alain ULg et al

in Prenatal Diagnosis (1989), 9(5), 373-5

A 46,XX;47,XX,+9;47,XX,+?mar karyotype was detected in an amniotic fluid cell culture and confirmed in a subsequent fetal blood sample from a 40-year-old woman. After termination of the pregnancy, none of ... [more ▼]

A 46,XX;47,XX,+9;47,XX,+?mar karyotype was detected in an amniotic fluid cell culture and confirmed in a subsequent fetal blood sample from a 40-year-old woman. After termination of the pregnancy, none of the 186 mitoses obtained from a second blood sample was trisomic for chromosome 9 (p less than 0.001). Selection against cells containing trisomy 9 is postulated to explain the disappearance of the lymphocyte clone. [less ▲]

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See detailMosaicism of Solid Gold supports the causality of a noncoding A-to-G transition in the determinism of the callipyge phenotype.
Smit, Maria; SEGERS, Karin ULg; Carrascosa, Laura Garcia et al

in Genetics (2003), 163(1), 453-6

To identify the callipyge mutation, we have resequenced 184 kb spanning the DLK1-, GTL2-, PEG11-, and MEG8-imprinted domain and have identified an A-to-G transition in a highly conserved dodecamer motif ... [more ▼]

To identify the callipyge mutation, we have resequenced 184 kb spanning the DLK1-, GTL2-, PEG11-, and MEG8-imprinted domain and have identified an A-to-G transition in a highly conserved dodecamer motif between DLK1 and GTL2. This was the only difference found between the callipyge (CLPG) allele and a phylogenetically closely related wild-type allele. We report that this SNP is in perfect association with the callipyge genotype. The demonstration that Solid Gold-the alleged founder ram of the callipyge flock-is mosaic for this SNP virtually proves the causality of this SNP in the determinism of the callipyge phenotype. [less ▲]

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See detailMosaiqs
Erpicum, Martin ULg; Rieppi, Stéphane ULg

Software (2009)

In order to simplify, facilitate and provide a methodology for the analysis of corpuses (interviews, focus groups, press articles, etc.), Spiral's Mosaiqs project offers a CAQDAS service that is both ... [more ▼]

In order to simplify, facilitate and provide a methodology for the analysis of corpuses (interviews, focus groups, press articles, etc.), Spiral's Mosaiqs project offers a CAQDAS service that is both simple and efficient. The exploration, firstly, enables the professional sciences to prepare for field work, including interviews, discussions son or any other text. It allows the development of the draft of the analysis grid, the professional socialization of its object of study and preparing for the examination phase. Finally, the analysis gives the professional the raw material that will be required for the preparation of its findings. Mosaiqs you work more effectively, more faithful to your body and in record time. [less ▲]

Detailed reference viewed: 96 (23 ULg)
See detailMosaïque
de Landsheere, Gilbert ULg

in Perspectives Documentaires en Sciences de l'Education (1989), 16

Detailed reference viewed: 6 (0 ULg)
See detailMosaïque (Itinéraire de lecture)
de Landsheere, Gilbert ULg

in Hassenforder, Jean (Ed.) Lecteurs et lectures en éducation (1993)

Detailed reference viewed: 5 (0 ULg)
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See detailMosaïque numérique et esthétique de la mondialisation
Mélon, Marc-Emmanuel ULg

in Belloi, Livio; Delville, Michel (Eds.) L'œuvre en morceaux. Esthétiques de la mosaïque (2006)

Si, comme l'écrit Lucien Dällenbach, la mosaïque constitue une allégorie de la mondialisation, ce n'est pas seulement par analogie. En effet, les technologies numériques et en particulier les réseaux ... [more ▼]

Si, comme l'écrit Lucien Dällenbach, la mosaïque constitue une allégorie de la mondialisation, ce n'est pas seulement par analogie. En effet, les technologies numériques et en particulier les réseaux, instruments privilégiés de la mondialisation, sont devenus producteurs de mosaïques (images et textes) à grande échelle. Cette idée est illustrée par l'analyse du principe de la photomosaïque, très répandue sur la toile, et de la production de l'artiste français Reynald Drouhin. [less ▲]

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See detailLa mosaïque pentecôtiste
Demart, Sarah ULg

in Politique : Revue de Débats (2013)

La transformation du paysage religieux de nos villes est une forme de la multiculturalité en acte. Mais celle-ci ne se réduit pas à l’islam qui mobilise la plupart des controverses. Le renouveau religieux ... [more ▼]

La transformation du paysage religieux de nos villes est une forme de la multiculturalité en acte. Mais celle-ci ne se réduit pas à l’islam qui mobilise la plupart des controverses. Le renouveau religieux qui se manifeste à l’intérieur des communautés congolaises mérite également l’intérêt. [less ▲]

Detailed reference viewed: 31 (3 ULg)
See detailMosaïque, Hommages à Pierre Somville
Denooz, Joseph ULg; Dortu, Véronique ULg; Steinmetz, Rudy ULg

Book published by CIPL (2007)

Detailed reference viewed: 95 (36 ULg)
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See detailThe Moses illusion: A follow-up on the focalization effect
Brédart, Serge ULg; Docquier, Marcel ULg

in Current Psychology of Cognition [=CPC] = Cahiers de Psychologie Cognitive [=CPC] (1989), 9

Detailed reference viewed: 314 (6 ULg)
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See detailMoses strikes again: Focalization effect on a semantic illusion
Brédart, Serge ULg; Modolo, K.

in Acta Psychologica (1988), 67(2), 135-144

Detailed reference viewed: 62 (3 ULg)
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See detailMosquito net for abdominal wall repair: a comparison of their chemical, physical, morphological and mechanical properties to commercial meshes
Sevrin, Chantal ULg; Nsadi Fwene, Berthier; Arung, Willy et al

in Biomedica proceedings (2013, June 23)

Meshes are the actual standard in abdominal wall repair. Commercial medical meshes are however either unavailable or unaffordable too expensive for developing countries. Therefore in most resource-poor ... [more ▼]

Meshes are the actual standard in abdominal wall repair. Commercial medical meshes are however either unavailable or unaffordable too expensive for developing countries. Therefore in most resource-poor developing countries a traditional sutured repair is still commonplace although with significantly inferior results. Sterilized mosquito nets have been recently roposed by several authors to replace medical meshes in low-income countries . However in the perspective of their clinical use a better understanding of this mosquito net is obviously requested both in terms of material properties and of in vivo biocompatibility. [less ▲]

Detailed reference viewed: 47 (8 ULg)