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See detailMuti-scale methods with strain-softening: damage-enhanced MFH for composite materials and computational homogenization for cellular materials with micro-buckling
Noels, Ludovic ULg; Nguyen, Van Dung ULg; Wu, Ling ULg et al

Scientific conference (2014, April 14)

Materials used in the aerospace industry, as composite or foamed materials are multiscale in nature. To predict the macroscopic behaviour of structures made of such materials, the micro-scopic responses ... [more ▼]

Materials used in the aerospace industry, as composite or foamed materials are multiscale in nature. To predict the macroscopic behaviour of structures made of such materials, the micro-scopic responses should also be computed within a nested scheme. This is particularly true when non-linear behaviours are modelled, or when the failure and post failure analyses are sought. In this work, multi-scale methods with strain softening are developed in the contexts of damage modelling for composite laminates and of buckling analyses in cellular materials. First, an anisotropic gradient–enhanced continuum damage model is embedded in a mean–field homogenization (MFH) process for elasto-plastic composites. The homogenization procedure is based on the newly developed incremental secant mean-field homogenization formulation, for which the residual stress and strain states reached in the phases upon a fictitious elastic unloading are considered as starting point to apply the secant method. The mean stress fields in the phases are then computed using isotropic secant tensors, which are naturally used to define the Linear Comparison–Composite The resulting multi– scale model is then applied to study the damage process at the meso–scale of laminates, and in particular the damaging of plies in a composite stack. By using the gradient–enhanced continuum damage model, the problem of losing uniqueness upon strain softening is avoided. Second, an efficient multi–scale finite element framework capturing the buckling instabilities in cellular materials is developed. As a classical multi–scale computational homogenization scheme loses accuracy with the apparition of the macroscopic localizations resulting from the micro–buckling, the second order multi–scale computational homogenization scheme is considered. This second–order computational framework is enhanced with the following novelties so that it can be used for cellular materials. At the microscopic scale, the periodic boundary condition is used because of its efficiency. As the meshes generated from cellular materials exhibit a large void part on the boundaries and are not conforming in general, the classical enforcement based on the matching nodes cannot be applied. A new method based on the polynomial interpolation2 without the requirement of the matching mesh condition on opposite boundaries of the representative volume element (RVE) is developed. Next, in order to solve the underlying macroscopic Mindlin strain gradient continuum of this second–order scheme by the displacement–based finite element framework, the treatment of high order terms is based on the discontinuous Galerkin (DG) method to weakly impose the C1-continuity. Finally, as the instability phenomena are considered at both scales of the cellular materials, the path following technique is adopted to solve both the macroscopic and microscopic problems. [less ▲]

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See detailCentral Pelvic spaces: Limits, content & landmarks
Bonnet, Pierre ULg

Conference (2014, April 14)

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See detailPelvic anatomy, a constructive approach
Bonnet, Pierre ULg

Conference (2014, April 14)

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See detailAnterolateral inferior abdominal wall anatomy: nerves and vessels.
Bonnet, Pierre ULg

Conference (2014, April 14)

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See detailThe path of the ureter
Bonnet, Pierre ULg

Conference (2014, April 14)

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See detailCumulative effect of Aox1 inactivation and N source modulation on the cellular proteome of Chlamydomonas reinhardtii - New insights in the metabolic interconnexion between respiration and photosynthesis
Gerin, Stéphanie ULg; Mathy, Grégory; Franck, Fabrice ULg

Conference (2014, April 14)

In Chlamydomonas reinhardtii, the Aox1 gene encoding the mitochondrial alternative oxidase (AOX) is tightly regulated by the N source: its transcription is stimulated by nitrate and repressed by ammonium ... [more ▼]

In Chlamydomonas reinhardtii, the Aox1 gene encoding the mitochondrial alternative oxidase (AOX) is tightly regulated by the N source: its transcription is stimulated by nitrate and repressed by ammonium. AOX has been proposed to play a key role in regards to the N source by acting as a trigger factor for the TCA cycle to promote the production of reduced cofactors which, together with photo-generated reductant, could contribute to support nitrate assimilation. In the present work, the cellular proteomes of wild-type and AOX-deficient strains grown either on nitrate or ammonium in the presence of acetate have been compared using two dimensional-differential in-gel electrophoresis (2D-DIGE) coupled to hierarchical clustering and ANOVA-2 statistical analyses in order to further investigate the physiological role(s) of AOX, particularly in regards to the N source. The dramatic up-regulation of chloroplastic components of the carbon-concentrating mechanism (CCM) in response to Aox1 inactivation importantly suggests that AOX plays a key role in the CCM in both N sources by allowing the production of CO2 through the TCA cycle. The concomitant down-regulation of photorespiratory enzymes in cells lacking AOX indicates that such an induction of the CCM could actually be sufficient to over-compensate the effects of AOX deficiency on CO2 availability in the local environment of Rubisco and maintain high rates of inorganic carbon fixation despite lower TCA cycle-mediated CO2 production. The global overexpression of diverse photosynthetic chain and Calvin cycle components in cells lacking AOX further evidences that a tight functional relationship exists between mitochondrial and chloroplastic processes of energy transduction, and that there could be a global redirection of bioenergetics towards photosynthesis to limit the harmful consequences (particularly oxidative stress) of mitochondrial deficiency. The observation that numerous N-responsive proteomic modifications are strongly attenuated (or even abolished) in response to Aox1 inactivation supports that AOX also exerts a more specific role as a central effector of the metabolic plasticity induced by modulating the N source in the growth medium. Our proteomic results tend notably to confirm that respiration (through AOX activity) and photosynthesis collaborate to provide nitrate reduction with electrons in mixotrophic condition and that acetate oxidation could be promoted to support AOX involvement in this context. [less ▲]

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See detailThe International Criminal Court as the Principal Authority for Defining the Boundaries of its own Human Rights Obligations
Deprez, Christophe ULg

Conference (2014, April 14)

This paper addresses the applicability of human rights standards to the activity of the International Criminal Court. It argues that, in practice, the Court itself is the key authority when it comes to ... [more ▼]

This paper addresses the applicability of human rights standards to the activity of the International Criminal Court. It argues that, in practice, the Court itself is the key authority when it comes to determining the content of its own human rights obligations. This paradox is due to the fact that the only two legal constructions on which the ICC can convincingly and practically be said to be bound by human rights law – i.e. those that are respectively based on general sources of international law and on the Court’s founding treaty – leave much discretion to the interpreter as to the content of the resulting duties. [less ▲]

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See detailThe A2 gene of alcelaphine herpesvirus-1 is a transcriptional regulator affecting cytotoxicity in virus-infected T cells but is not required for malignant catarrhal fever induction in rabbits.
Parameswaran, Nevi; Dewals, Benjamin G ULg; Giles, Tom C. et al

in Virus research (2014)

Alcelaphine herpesvirus-1 (AlHV-1) causes malignant catarrhal fever (MCF). The A2 gene of AlHV-1 is a member of the bZIP transcription factor family. We wished to determine whether A2 is a virulence gene ... [more ▼]

Alcelaphine herpesvirus-1 (AlHV-1) causes malignant catarrhal fever (MCF). The A2 gene of AlHV-1 is a member of the bZIP transcription factor family. We wished to determine whether A2 is a virulence gene or not and whether it is involved in pathogenesis by interference with host transcription pathways. An A2 gene knockout (A2DeltaAlHV-1) virus, revertant (A2revAlHV-1) virus, and wild-type virus (wtAlHV-1) were used to infect three groups of rabbits. A2DeltaAlHV-1-infected rabbits succumbed to MCF, albeit with a delayed onset compared to the control groups, so A2 is not a critical virulence factor. Differential gene transcription analysis by RNAseq and qRT-PCR validation of a selection of these was performed in infected large granular lymphocyte (LGL) T cells obtained in culture from the MCF-affected animals. A2 was involved in the transcriptional regulation of immunological, cell cycle and apoptosis pathways. In particular, there was a bias towards gammadelta T cell receptor (TCR) expression and downregulation of alphabeta TCR. TCR signalling, apoptosis, cell cycle, IFN-gamma and NFAT pathways were affected. Of particular interest was partial inhibition of the cytotoxicity-associated pathways involving perforin and the granzymes A and B in the A2DeltaAlHV-1-infected LGLs compared to controls. In functional assays, A2DeltaAlHV-1-infected LGLs were significantly less cytotoxic than wtAlHV-1- and A2revAlHV-1-infected LGLs using rabbit corneal epithelial cells (SIRC) as targets. This implies that A2 is involved in a pathway enhancing the expression of LGL cytotoxicity. This is important as virus-infected T cell cytotoxicity in vivo has been suggested as a potential mechanism of disease induction in MCF. [less ▲]

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See detailDeception and the value of truth: a case study from the fifteenth century
Bauden, Frédéric ULg

Scientific conference (2014, April 13)

Detailed reference viewed: 25 (5 ULg)
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See detailWhat about Google Scholar when searching information in Human and Physical Geography?
Stirbu, Simona ULg

Conference (2014, April 12)

This study focuses on four bibliographic tools and aims to highlight what the use of the Google Scholar search engine can yield, in comparison with three commercial bibliographical databases: the well ... [more ▼]

This study focuses on four bibliographic tools and aims to highlight what the use of the Google Scholar search engine can yield, in comparison with three commercial bibliographical databases: the well known multidisciplinary database Web of Science (WoS); GeoRef, a specialized data base in geosciences; and FRANCIS, which includes international geographical bibliography. To identify the bibliographic references published yearly between the years 2005 to 2009, ten keywords placed between quotation marks have been searched through the title field of the search tool interfaces. On a monthly basis, from November 2010 to July 2011, an identical process was repeated to get some information on the repeatability of the searches. Initially the whole set of results was analysed, and then the search results of two keywords were studied in more details. The results indicate that GS provides a high overlap with the search results of the other databases, but also yields numerous unique hits. Moreover, it seems that it is also able to find diverse types of literature, while the others are more specialized. [less ▲]

Detailed reference viewed: 57 (10 ULg)
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See detailInfrared Holography
Georges, Marc ULg

Scientific conference (2014, April 11)

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See detailXenogeneic GVHD in NSG mice: focus on rapamycin
Ehx, Grégory ULg

Conference (2014, April 11)

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See detail"Gefühltes Komma - richtiges Komma?"
Münzberg, Franziska ULg

Scientific conference (2014, April 11)

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See detailPhylogenetic study of Aedes albopictus and Aedes koreicus (Diptera, Culicidae) origin, two invasive mosquito species in Belgium
Raharimalala, Fara Nantenaina ULg; Boukraa, Slimane ULg; Bawin, Thomas ULg et al

Poster (2014, April 10)

The main ways of the introduction of invasive mosquito species in Europe were greatly facilitated by the importation of used tires and plants from the South of China (Dracaena sanderiana, called "Lucky ... [more ▼]

The main ways of the introduction of invasive mosquito species in Europe were greatly facilitated by the importation of used tires and plants from the South of China (Dracaena sanderiana, called "Lucky bamboo"), which are a very good breeding sites of these mosquitoes (www.eidatlantique.eu). For Belgium, several species of exotic mosquitoes have already been listed such as Ochlerotatus japonicus japonicus, Aedes albopictus and A. koreicus. We have captured one male of A. albopictus in Belgium in July 2013 (Boukraa et al, 2013), and teams from other entomologist have been able to find several individuals in the months that have followed our discovery (personal communication). However, his presence was reported first in 2000 (Schaffner et al. 2004) but until 2012, no individuals have been found (Versteirt et al., 2013). We also could find larvae of A. koreicus in abundance. These discovery suggest that these two invasive species are being established in Belgium. Methods: Adult mosquitoes were collected by CO2-baited traps Mosquito Magnet Liberty Plus (MMLP) and immature stages by the dipping method from 8 sites of Belgium. Each individual was then determined morphologically. For A. albopictus and A. koreicus, reconfirmation by molecular method was performed with COI and ND5 mitochondrial primers and sequences were then aligned with those of mosquitoes available in databases by using BioEdit and Multialn softwares. The two gene sequences were concatenated to improve the reliability of the phylogenetic analysis and were carried out by using the Seaview software based on maximum likelihood (ML) methods. Trees were then constructed with the general time reversible (GTR) model, and branch supports were estimated by bootstrapping with 1000 replicates. Result: The aim of this work will focus on the study of the probable origin of these two species of Aedes, which are for the moment safe yet, but that might become dangerous in the event of massive outbreak. The knowledge of the probably origin of the two invasive mosquitoes allow take more protection against their way to enter in the country. [less ▲]

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See detailSame-sex parenting is legal in Belgium but some heterosexuals support it and others don't: why?
Scali, Thérèse ULg; D'Amore, Salvatore ULg; Green, Robert-Jay

Poster (2014, April 10)

Gays and Lesbians represent between 7 and 10% of the Belgian population, this means 1 million of citizens. Notwithstanding the large number of civil rights granted to homosexuals and the anti ... [more ▼]

Gays and Lesbians represent between 7 and 10% of the Belgian population, this means 1 million of citizens. Notwithstanding the large number of civil rights granted to homosexuals and the anti-discrimination laws, the issue of social acceptance of same-sex couples and families remains. However, the attitude of the population (support vs. rejection and discrimination) and the marginalization of a minority influence not only their quality of life but also their couple and parenting skills and the development of their children (Armesto, 2002; Goldberg, 2010). Results show that attitudes towards same-sex parenting can be explained by four categories of arguments: arguments regarding children well-beeing, religious and political arguments, contact and experiential arguments and traditional arguments. [less ▲]

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See detailCapire gli attegiamenti nei confronti degli omogenitori in Belgio
Scali, Thérèse ULg

Scientific conference (2014, April 10)

La situazione sociale per i genitori gay e lesbiche in Belgio. I predittori degli atteggiamenti positivi e negativi verso l’omogenitorialità. Le famiglie Rainbow in Belgio: cosa permette la legge? Miti e ... [more ▼]

La situazione sociale per i genitori gay e lesbiche in Belgio. I predittori degli atteggiamenti positivi e negativi verso l’omogenitorialità. Le famiglie Rainbow in Belgio: cosa permette la legge? Miti e stereotipi sulle famiglie omogenitoriali. Perché alcuni Belgi non sostengono gli omogenitori? Il ruolo del « benessere » del bambino. Cosa si può fare? [less ▲]

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See detailParcelles expérimentales de la sylviculture d'arbres-objectifs
Perin, Jérôme ULg

Diverse speeche and writing (2014)

Présentation du réseau de dispositifs expérimentaux et de l'état des recherches de GxABT concernant la sylviculture d'Arbres-objectifs.

Detailed reference viewed: 16 (2 ULg)