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See detailApoptosis of Sertoli cells after conditional ablation of murine double minute 2 (Mdm2) gene is p53-dependent and results in male sterility.
Fouchecourt, S.; Livera, G.; Messiaen, S. et al

in Cell death and differentiation (2015)

Beside its well-documented role in carcinogenesis, the function of p53 family has been more recently revealed in development and female reproduction, but it is still poorly documented in male reproduction ... [more ▼]

Beside its well-documented role in carcinogenesis, the function of p53 family has been more recently revealed in development and female reproduction, but it is still poorly documented in male reproduction. We specifically tested this possibility by ablating Mdm2, an E3 ligase that regulates p53 protein stability and transactivation function, specifically in Sertoli cells (SCs) using the AMH-Cre line and created the new SC-Mdm2-/- line. Heterozygous SC-Mdm2-/+ adult males were fertile, but SC-Mdm2-/- males were infertile and exhibited: a shorter ano-genital distance, an extra duct along the vas deferens that presents a uterus-like morphology, degenerated testes with no organized seminiferous tubules and a complete loss of differentiated germ cells. In adults, testosterone levels as well as StAR, P450c17 (Cyp17a1) and P450scc (Cyp11a1) mRNA levels decreased significantly, and both plasma LH and FSH levels increased. A detailed investigation of testicular development indicated that the phenotype arose during fetal life, with SC-Mdm2-/- testes being much smaller at birth. Interestingly, Leydig cells remained present until adulthood and fetal germ cells abnormally initiated meiosis. Inactivation of Mdm2 in SCs triggered p53 activation and apoptosis as early as 15.5 days post conception with significant increase in apoptotic SCs. Importantly, testis development occurred normally in SC-Mdm2-/- lacking p53 mice (SC-Mdm2-/-p53-/-) and accordingly, these mice were fertile indicating that the aforementioned phenotypes are entirely p53-dependent. These data not only highlight the importance of keeping p53 in check for proper testicular development and male fertility but also certify the critical role of SCs in the maintenance of meiotic repression.Cell Death and Differentiation advance online publication, 16 October 2015; doi:10.1038/cdd.2015.120. [less ▲]

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See detailEctopic Expression of Retrotransposon-Derived PEG11/RTL1 Contributes to the Callipyge Muscular Hypertrophy.
Xu, Xuewen; Ectors, Fabien ULg; Davis, Erica E. et al

in PloS one (2015), 10(10), 0140594

The callipyge phenotype is an ovine muscular hypertrophy characterized by polar overdominance: only heterozygous +Mat/CLPGPat animals receiving the CLPG mutation from their father express the phenotype ... [more ▼]

The callipyge phenotype is an ovine muscular hypertrophy characterized by polar overdominance: only heterozygous +Mat/CLPGPat animals receiving the CLPG mutation from their father express the phenotype. +Mat/CLPGPat animals are characterized by postnatal, ectopic expression of Delta-like 1 homologue (DLK1) and Paternally expressed gene 11/Retrotransposon-like 1 (PEG11/RTL1) proteins in skeletal muscle. We showed previously in transgenic mice that ectopic expression of DLK1 alone induces a muscular hypertrophy, hence demonstrating a role for DLK1 in determining the callipyge hypertrophy. We herein describe newly generated transgenic mice that ectopically express PEG11 in skeletal muscle, and show that they also exhibit a muscular hypertrophy phenotype. Our data suggest that both DLK1 and PEG11 act together in causing the muscular hypertrophy of callipyge sheep. [less ▲]

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See detailLes souvenirs définissant le soi - Quel est l'intérêt de les aborder dans l’entretien clinique ? - Illustration dans le trouble dépressif majeur
Wagener, Aurélie ULg; Boulanger, Marie ULg; Blairy, Sylvie ULg

Scientific conference (2015, October 16)

Les souvenirs définissant le soi (« Self-Defining Memories ») sont des souvenirs autobiographiques particuliers, conceptualisés comme une cristallisation des liens entre mémoire et identité. Ces souvenirs ... [more ▼]

Les souvenirs définissant le soi (« Self-Defining Memories ») sont des souvenirs autobiographiques particuliers, conceptualisés comme une cristallisation des liens entre mémoire et identité. Ces souvenirs semblent particulièrement intéressants pour la définition que nous avons de nous-mêmes et pour la clarté du concept de soi. Nous définirons ces souvenirs et fourniront quelques exemples issus de notre pratique clinique. Nous présenterons leurs caractéristiques (spécificité, intégration, contenu, valence émotionnelle). Nous évoquerons l'intérêt que nous voyons à aborder ces souvenirs dans l'entretien clinique comme outil servant à aider les patients présentant une faible clarté du concept de soi ou encore des difficultés liées à la définition de soi. Nous présenterons également des pistes de prise en charge concrètes. Sur base des résultats de recherches menées au sein de l'unité de psychologie clinique comportementale et cognitive, nous présenterons les caractéristiques particulières de ces souvenirs chez les patients dépressifs, comparés à des sujets contrôles sains. [less ▲]

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See detailL'étude de cas en psychologie clinique
Naziri, Despina ULg

Scientific conference (2015, October 16)

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See detailThe development of Structural Fire Engineering over the past 25 years and issues for the future
Franssen, Jean-Marc ULg

Conference (2015, October 15)

This talk presents a series of thoughts of the author from his observation of the evolution of structural fire engineering since the beginning of his career Experimental research works are discussed ... [more ▼]

This talk presents a series of thoughts of the author from his observation of the evolution of structural fire engineering since the beginning of his career Experimental research works are discussed, either on the behavior of materials or on the behavior of structures. The rest of the presentation is dedicated to calculation methods: tabulated data, simple calculation models and general calculation models. For numerical calculation models, the presentation contains a brief history of appearance of different software, of their objectives, of their capabilities… Some examples are presented of structures recently modelled in real applications. Possible abusive utilizations of numerical modelling are also shown. The presentation ends with a presentation of some challenges that the discipline is facing for the future. [less ▲]

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See detailMise au point sur les neuropathies héréditaires
WANG, François-Charles ULg; BOUQUIAUX, Olivier ULg

Scientific conference (2015, October 15)

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See detailBelgian International Lawyers and WWI. Networks, Experience and Memory
Genin, Vincent ULg

Poster (2015, October 15)

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See detailLa médecine de famille, une connaissance complexe et multi facettes
Jamoulle, Marc ULg

Conference (2015, October 15)

Dans les conditions difficiles que doit affronter la Tunisie, soit faire face a l'augmentation de la demande en soins de santé, à l'amélioration de la qualité et à la transition démographique et ... [more ▼]

Dans les conditions difficiles que doit affronter la Tunisie, soit faire face a l'augmentation de la demande en soins de santé, à l'amélioration de la qualité et à la transition démographique et épidémiologique, la Médecine de Famille représente un atout certain. L'image internationale peu flatteuse de la médecine de famille Tunisienne est présentée au travers de sa présence dans les publications scientifiques. Une série de concepts spécifiques de la Médecine de Famille sont exposés ; la complexité, l'extension de la connaissance, l'incertitude, les différents niveaux de l'action. Leur prise en compte permet d'appeler à un autre regard et à un appel à écrire le métier d'une façon différente. Pour en sortir définitivement avec l'image délétère de ce métier exigeant. [less ▲]

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See detailDo Burundians have a more positive perception of older people than immigrants or Belgians?
Marquet, Manon ULg; Missotten, Pierre ULg; Nindaba, Desiderate et al

Poster (2015, October 15)

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See detailEfficient standard error formulas of ability estimators in item response theory
Magis, David ULg

Conference (2015, October 15)

This talk focuses on the computation of asymptotic standard errors (ASE) of ability estimators with dichotomous item response models. A general framework is considered, and ability estimators are defined ... [more ▼]

This talk focuses on the computation of asymptotic standard errors (ASE) of ability estimators with dichotomous item response models. A general framework is considered, and ability estimators are defined from a very restricted set of assumptions and formulas. This approach encompasses most standard methods such as maximum likelihood, weighted likelihood, maximum a posteriori, and robust estimators. A general formula for the ASE is derived from the theory of M-estimation. Well-known results are found back as particular cases for the maximum and robust estimators, while new ASE proposals for the weighted likelihood and maximum a posteriori estimators are presented. These new formulas are compared to traditional ones by means of a simulation study under Rasch modeling. [less ▲]

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See detailEFFECTS OF AGRICULTURAL PRACTICES AND HEAVY METAL CONTAMINATION ON THE COMMUNITY DYNAMICS OF EARTHWORMS IN RELATION TO SOIL PHYSICAL AND CHEMICAL FACTORS IN AGRICULTURAL FIELDS (BELGIUM)
Lemtiri, Aboulkacem ULg

Doctoral thesis (2015)

We investigated the effect of different agricultural practices on the abundances, biomass, and species diversity of earthworms. Specifically, we aimed to identify the relationship between certain soil ... [more ▼]

We investigated the effect of different agricultural practices on the abundances, biomass, and species diversity of earthworms. Specifically, we aimed to identify the relationship between certain soil physico-chemical properties and earthworm communities in agricultural soils. Two tillage systems and crop residue management were investigated. After conducting the study over four years, we found that the abundance, biomass, and diversity of earthworms were negatively affected by tillage application and the removal of crop residues. All ecological groups were negatively affected by conventional tillage system and crop residues exportation. However, crop residues removal had a greater impact than the conventional tillage system. In this study area, the earthworm community was dominated by the endogeic species A. c. caliginosa (64%), while few epigeic and anecic species were observed (5%). Endogeic and epi-anecic (L. terrestris) species appeared to be highly influenced by tillage and of crop residues exportation. When crop residues were exported from the field, the concentrations of chemical elements were low, particularly P and K nutrients. Earthworm activity contributed to nutrient dynamics and soil structure after four years of incorporating of crop residues to the fields and reduced tillage application. No consistent relationship was detected between soil and earthworm variables, even though different soil properties responded differently with respect to the tillage systems, crop residues removal and the presence of certain earthworm species. The number of years that our field was managed might have also affected our results.On the basis of the primarily research focused on understanding how earthworms participate and contribute towards improving soil quality (structure, nutrient dynamics and fertility), we subsequently focused on investigating how two plants (Vicia faba and Zea mays) and the Eisenia fetida earthworm contribute to uptake of different metals: Cd, Zn, Pb and Cu from the land surrounding of a former Zn-Pb ore treatment plant. Specifically, we tested whether the earthworm Eisenia fetida could act as a catalyzor to enhance phytoremediation efficiency. After 42 days of exposure, our results showed that certain earthworm life-cycle traits are affected by metal contamination and by the addition of plants. Specifically, the concentrations of metals in earthworm tissues decreased in the presence of plants. Our findings demonstrate that earthworm activities modify the availability of metals in soils, enhancing metal uptake by plants. This innovative system offers new investigation possibilities by considering earthworm-plant-soil interaction. In conclusion, this work confirmed that earthworms are important catalyzor optimizing the phytoremediation processes of polluted soils. [less ▲]

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See detailL’insécurité de l’exclusion sociale : comment sortir de l’impuissance ?
Glowacz, Fabienne ULg

Scientific conference (2015, October 15)

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See detailFiguras de traductor (no) profesional
Willson, Patricia ULg

Scientific conference (2015, October 15)

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See detailShear banding modelling in cross-anisotropic rocks
Pardoen, Benoît ULg; Seyedi, D.M.; Collin, Frédéric ULg

in International Journal of Solids and Structures (2015), 72

Sedimentary geomaterials such as rocks frequently exhibit cross-anisotropic properties and their behaviour depends on the direction of loading with respect to their microstructure. As far as material ... [more ▼]

Sedimentary geomaterials such as rocks frequently exhibit cross-anisotropic properties and their behaviour depends on the direction of loading with respect to their microstructure. As far as material rupture is concerned, localised deformation in shear band mode appears generally before cracks and material failure. The influence of cross-anisotropy on the shear strain localisation remains an important issue and is investigated in the present study. To do so, a constitutive elastoplastic cross-anisotropic model that includes anisotropy both on the elastic and plastic characteristics is defined. For the plastic part of the model, the anisotropy of a strength parameter is introduced with a microstructure fabric tensor. Then, the fractures are modelled with finite element methods by considering the development of shear strain localisation bands and an enriched model is used to properly reproduce the shear banding. The cross-anisotropy influence on shear banding is studied through numerical applications of small and large-scale geotechnical problems that engender fractures. The two considered applications are a plane-strain biaxial compression test and an underground gallery excavation. The numerical results provide information about the influence of cross-anisotropy on the appearance and development of shear bands. It has been noticed, among other observations, that the material strength vary with the loading direction and that the development and the shape of the excavation fractured zone that develops around a gallery is strongly influenced by the material anisotropy. [less ▲]

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See detailEnvironmental impact assessment of bio-based binders: from production to industrial applications
Gerbinet, Saïcha ULg; Belboom, Sandra ULg; Briard, Vincent et al

Poster (2015, October 15)

A binder is used to hold together the fibers forming the mineral wool products (see figure 1). These fibers can be produced from sand and recycled glass for glass wool products (see figure 2) or from rock ... [more ▼]

A binder is used to hold together the fibers forming the mineral wool products (see figure 1). These fibers can be produced from sand and recycled glass for glass wool products (see figure 2) or from rock (volcanic rock, typically basalt or dolomite) for stone wool products. Traditionally, the binders used in mineral wool products are based on phenol-formaldehyde. Due to sanitary and environmental considerations and increased focus on indoor air quality, the producers developed new alternative binders. Especially, Knauf Insulation, a worldwide building insulation manufacturer, developed a binder based on plant starch and called ECOSE. In addition of not using added phenol-formaldehyde , this new binder is also supposed to reduce the environmental impacts of Knauf Insulation mineral wools. Moreover, due to its properties, others applications are now considered for ECOSE such as composite wood panels [1]. The aim of this study is to determine the environmental impact of ECOSE and to compare it with more traditional binders using Life Cycle Assessment (LCA) methodology. LCA analyzes the environmental aspects and potential impacts associated with all the stages of a product's life. In this type of environmental assessment the energy and material flows for the entire life-cycle are surveyed and analyzed with special attention to possible environmental hazards or human health problems. The ISO 14040 and 14044 norms [2, 3] provide the general guidance for performing an LCA. The LCA methodology is first applied to ECOSE main component: glucose. The presentation will present results for glucose production from cereals starches After that, first ECOSE application, glass mineral wool products will be presented in details, including production process (see figure 3). The modelling of the glass mineral wool production process in LCA software GaBi 6 [4] is then described. One of the model specificity is that it allows to perform LCA of any glass wool products produced in Knauf Insulation plants in Europe. The adaptations to the model to allow studying former glass wool product when using phenol-formaldehyde binders will also be presented such as the advantages of this model. Moreover, preliminary results about ECOSE and phenol-formaldehyde glass wool products are explained. Références [1] Knauf Insulation. [cited 2014; Available from: http://www.knaufinsulation.ua/en. [2] ISO 14044, Environmental management - Life cycle assessment - Requirements and guidelines. 2006. [3] ISO 14040, Environmental management - Life cycle assessment - Principles and framework. 2006. [4] LBP, University of Stuttgart, and PE INTERNATIONAL AG, GaBI 6. 2012: Leinfelden-Echterdingen. p. GaBi 6: Software and database for life cycle engineering. [less ▲]

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See detailBelgian children’s and adolescents’ views on the elderly
Flamion, Allison ULg; Missotten, Pierre ULg; Schroyen, Sarah ULg et al

Poster (2015, October 15)

Detailed reference viewed: 19 (6 ULg)
See detail"Lirécrire pour apprendre" : d'un outil d'enseignement à sa mise en oeuvre au 1er degré de l'enseignement secondaire
De Croix, Séverine ULg; Wyns, Marielle

Diverse speeche and writing (2015)

Formation à la mise en oeuvre, dans les classes de 1re secondaire, de l'outil "Lirécrire pour apprendre" (Chaire Lirécrire, Fondation Louvain, UCL). Ce dispositif didactique et pédagogique est centré sur ... [more ▼]

Formation à la mise en oeuvre, dans les classes de 1re secondaire, de l'outil "Lirécrire pour apprendre" (Chaire Lirécrire, Fondation Louvain, UCL). Ce dispositif didactique et pédagogique est centré sur l'enseignement explicite, dans l'ordinaire de la classe, des stratégies de lecture nécessaires à la compréhension des textes et des opérations d'écriture requises pour réussir à l'école. [less ▲]

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See detailLe stress à l’aune des neurosciences
Desseilles, Martin ULg

Scientific conference (2015, October 15)

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