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Is the bowshock of the runaway massive star HD 195592 a Fermi source?
; ; De Becker, Michaël
in Astronomy and Astrophysics (2013), 550
HD 195592 is an O-type super-giant star, known as a well-established runaway. Recently, a Fermi gamma-ray source (2FGL J2030.7+4417) with a position compatible with that of HD 195592 has been reported ... [more ▼]
HD 195592 is an O-type super-giant star, known as a well-established runaway. Recently, a Fermi gamma-ray source (2FGL J2030.7+4417) with a position compatible with that of HD 195592 has been reported. Our goal is to explore the scenario where HD 195592 is the counterpart of the Fermi gamma-ray source modeling the non-thermal emission produced in the bowshock of the runaway star. We calculate the spectral energy distribution of the radiation produced in the bowshock of HD 195592 and we compare it with Fermi observations of 2FGL J2030.7+4417. We present relativistic particle losses and the resulting radiation of the bowshock of HD 195592 and show that the latter is compatible with the detected gamma-ray emission. We conclude that the Fermi source 2FGL J2030.7+4417 might be produced, under some energetic assumptions, by inverse Compton up-scattering of photons from the heated dust in the bowshock of the runaway star. HD 195592 might therefore be the very first object detected belonging to the category of gamma-ray emitting runaway massive stars, whose existence has been recently predicted. [less ▲]Detailed reference viewed: 52 (30 ULg)
Sirtuin 1 enzymatic activity is required for cartilage homeostasis in vivo in a mouse model.
; Sanchez, Christelle ; et al
in Arthritis and Rheumatism (2013), 65(1), 159-66
OBJECTIVE: We and others previously demonstrated that sirtuin 1 (SIRT-1) regulates apoptosis and cartilage-specific gene expression in human chondrocytes and mouse models. This study was undertaken to ... [more ▼]
OBJECTIVE: We and others previously demonstrated that sirtuin 1 (SIRT-1) regulates apoptosis and cartilage-specific gene expression in human chondrocytes and mouse models. This study was undertaken to determine if SIRT-1 enzymatic activity plays a protective role in cartilage homeostasis in vivo, by investigating mice with SIRT-1 mutations to characterize their cartilage. METHODS: Articular cartilage was harvested from the paws and knees of 5- and 6-month-old wild-type (WT) mice and mice homozygous for SIRT-1(tm2.1Mcby) (SIRT-1(y/y) ), an allele carrying a point mutation that encodes a SIRT-1 protein with no enzymatic activity (y/y mice). Mice ages 2 days old and 6-7 days old were also examined. Mouse joint cartilage was processed for histologic examination or biochemical analyses of chondrocyte cultures. RESULTS: We found that articular cartilage tissue sections from y/y mice of up to 6 months of age contained reduced levels of type II collagen, aggrecan, and glycosaminoglycan compared to sections from WT mice. In contrast, protein levels of matrix metalloproteinase 8 (MMP-8), MMP-9, and MMP-13 were elevated in the cartilage of y/y mice. In addition, chondrocyte apoptosis was elevated in SIRT-1 mutant mice as compared to their WT littermates. Consistent with these observations, protein tyrosine phosphatase 1b was elevated in the y/y mice. CONCLUSION: Our in vivo findings in this animal model demonstrate that mice with defective SIRT-1 also have defective cartilage, with elevated rates of cartilage degradation with age. Hence, normal cartilage homeostasis requires enzymatically active SIRT-1 protein. [less ▲]Detailed reference viewed: 2 (0 ULg)
Dike-break induced flows: a simplified model
Stilmant, Frédéric ; Pirotton, Michel ; Archambeau, Pierre et al
in Environmental Fluid Mechanics (2013), 13(1), 89-100
A simplified model for the prediction of the steady-state outflowthrough a breach in an inland dike is presented. It consists in the application of the mass and momentum conservation principles to a ... [more ▼]
A simplified model for the prediction of the steady-state outflowthrough a breach in an inland dike is presented. It consists in the application of the mass and momentum conservation principles to a macroscopic control volume. A proper definition of the shape of the control volume enables to take the main characteristics of the flow into account and thus to compensate for the extreme simplification of the spatial representation of the model. At the breach, a relation derived from the shallow-water equations is used to determine the direction of the flow. Developments have been guided by numerical simulations and results have been compared to experimental data. Both the accuracy and the domain of validity of the simplified model are found satisfactory. [less ▲]Detailed reference viewed: 46 (12 ULg)
Use of GFP whole cell microbial biosensors for the investigation of the scale-up and scale-down effect on biopharmaceutical processes
Delvigne, Frank ; Brognaux, Alison ; et al
Book published by Momentum press (2013)Detailed reference viewed: 15 (4 ULg)
Intégration du stress microbien pour le scaling-up des bioréacteurs
Scientific conference (2013)Detailed reference viewed: 10 (3 ULg)
Visean corals from the transverse Jebel Begaa to Gara el Itima (eastern Tafilalt, Morocco)
; Denayer, Julien
in Document de l'Institut Scientifique, Rabat (2013), 26Detailed reference viewed: 6 (1 ULg)
an attempt of time calibration of the Lower Tournaisian (Hastarian Substage) based on orbitally forced sequences
Poty, Edouard ; Mottequin, Bernard ; Denayer, Julien
in Document de l'Institut Scientifique, Rabat (2013), 26Detailed reference viewed: 15 (2 ULg)
L'anthropologue en plein conflit: secrets, silences et éthique en anthropologie du droit
En mai dernier, je déjeunais avec un ami avocat lorsqu’il me fit part de l’anecdote suivante : quelques mois auparavant, il remportait une affaire pour laquelle une compensation financière, destinée à des ... [more ▼]
En mai dernier, je déjeunais avec un ami avocat lorsqu’il me fit part de l’anecdote suivante : quelques mois auparavant, il remportait une affaire pour laquelle une compensation financière, destinée à des clients, avait été versée sur son compte bancaire. Comme ces derniers ne réclamaient pas immédiatement leur dû, l’avocat décida alors d’investir le montant qui « dormait dans son compte » en le prêtant à une connaissance. Lorsque les clients se manifestèrent enfin, il leur restitua l’argent et conserva les intérêts. Au-delà de la protection de l'anonymat de mon informateur, aurais-je dû garder cette anecdote secrète? Dans le cadre de mes recherches sur les conflits d’héritage au Sud-Bénin, je me suis intéressée au fonctionnement des tribunaux, aux pratiques des professionnels de la justice et à leurs relations avec les usagers. Je me suis penchée sur les arguments des parties, sur leur conception du droit et sur leur parcours depuis les funérailles jusqu'au tribunal ou au bureau du notaire. Je reviendrai ici sur les difficultés pratiques et éthiques de mon travail sur le terrain. En effet, s’intégrer au point de passer presque inaperçu est l'objectif de tout anthropologue ayant recours à l'observation participante. Il s’agit pour nous d’une manière de découvrir les « relations réelles » et les jeux de pouvoir, d'aller au-delà des discours officiels dans lesquels la réalité paraît souvent trop bien rangée. Au-delà des limites en termes d’accès à l’information, quelles sont les conséquences en matière d'éthique et de consentement? Comment utiliser ce que nos informateurs mentionnent « off the record », avant ou après un entretien, les choses qu'ils expliquent alors que nous les accompagnons lors d’une journée de travail? Lorsque l'observateur n’est plus perçu comme tel, mais comme un confident, le consentement des participants ne devient-il pas implicite, voire même caduc? Lorsque l’on touche aux dynamiques familiales, aux situations conflictuelles et au secret professionnel, nombreuses sont aussi les questions auxquelles les gens refusent de répondre, les institutions qui déclinent certaines demandes d'accès. Il s’agit alors de comprendre ce à quoi les gens disent « non » et pourquoi. Enfin, si des solutions pour contourner les limites inhérentes à toute recherche sont envisageables, ces dernières vont de pair avec une série de questions éthiques. Peut-on contacter une partie à l'insu de l'autre et ainsi trahir la confiance de certains informateurs ? Provoquer sur base d'informations obtenues lors d'autres entretiens ? Ces questions soulèvent également celle, plus large, de la propriété des données : peut-on considérer qu'une fois enregistré, un entretien appartient à celui qui l'a réalisé ? Qu'en est-il, enfin, du rôle de l'anthropologue « en plein conflit » ? Ces questions sont particulièrement pertinentes dans le cadre d’une ethnographie des administrations publiques (dans mon cas, les tribunaux) en Afrique de l'Ouest : fortement subventionnées par des organismes occidentaux, la pratique montre cependant que ces institutions ne correspondent pas (encore) au standard de la bureaucratie « rationnelle » occidentale. Dans ce cadre, la manière dont les professionnels décrivent leurs pratiques quotidiennes, ce qu’ils acceptent de dire – et à qui – est définitivement partie intégrante de l’analyse. Entre des secrets difficiles à garder et des silences qui en disent parfois long, je reviendrai ici sur la manière dont j’ai abordé mon terrain, sur les difficultés pratiques et sur les dilemmes éthiques. [less ▲]Detailed reference viewed: 8 (2 ULg)
Nonlinear Normal Modes of Nonconservative Systems
Renson, Ludovic ; Kerschen, Gaëtan
in Proceedings of the SEM IMAC XXXI Conference (2013)
Linear modal analysis is a mature tool enjoying various applications ranging from bridges to satellites. Nevertheless, modal analysis fails in the presence of nonlinear dynamical phenomena and the ... [more ▼]
Linear modal analysis is a mature tool enjoying various applications ranging from bridges to satellites. Nevertheless, modal analysis fails in the presence of nonlinear dynamical phenomena and the development of a practical nonlinear analog of modal analysis is a current research topic. Recently, numerical techniques (e.g., harmonic balance, continuation of periodic solutions) were developed for the computation of nonlinear normal modes (NNMs). Because these methods are limited to conservative systems, the present study targets the computation of NNMs for nonconservative systems. Their definition as invariant manifolds in phase space is considered. Specifically, a new finite element technique is proposed to solve the set of partial differential equations governing the manifold geometry. [less ▲]Detailed reference viewed: 16 (4 ULg)
Managers’ competences in social enterprises: which specificities?
Moreau, Charlotte ; Mertens de Wilmars, Sybille
in Social Enterprise Journal (2013)
The management of an organization and the context within which this organization evolves are recognized as two important aspects of any organization. Few studies have been conducted however on the ... [more ▼]
The management of an organization and the context within which this organization evolves are recognized as two important aspects of any organization. Few studies have been conducted however on the management function within the specific context of social enterprises, organizations that mix social goals and economic imperatives (Darbus & Lazuech, 2010). This paper examines the specific competences of management in social enterprises, by constructing a competence model, the emblematic tool of competence-based management, relevant to the management of social enterprises (Colin & Grasser, 2007; Oiry & Sulzer, 2002; Retour & Rapiaux, 2006). Our hypothesis is that certain competences required of managers in social enterprises are specific, regarding the particular internal and external context of social enterprises, the governance model, etc. The methodology used is based on four main steps: a review of the literature and the conducting of exploratory interviews, the construction of a first draft of the competence model, the conducting of group interviews with managers of social enterprises in six European countries as this research takes place within the framework of a European research project on lifelong learning , and the final adaptation and validation of the competence model. [less ▲]Detailed reference viewed: 44 (7 ULg)
Peut-on améliorer l'enseignement de concepts scientifiques par la mise en place d'un dispositif de collaboration en formation initiale des enseignants ?
in Puzzle (2013), 32(2), 100-102Detailed reference viewed: 6 (0 ULg)
Zavalíaite, (Mn2+,Fe2+,Mg)3(PO4)2, a new member of the sarcopside group from the La Empleada pegmatite, San Luis Province, Argentina.
Hatert, Frédéric ; Roda-Robles, Encarnacion ; et al
in Canadian Mineralogist (2013), 50Detailed reference viewed: 3 (0 ULg)
Mineralogy and geochemistry of phosphates and silicates in the Sapucaia pegmatite, Minas Gerais, Brazil: genetical implications.
Baijot, Maxime ; Hatert, Frédéric ;
in Canadian Mineralogist (2013), 50Detailed reference viewed: 6 (1 ULg)
CNMNC guidelines for the use of suffixes and prefixes in mineral nomenclature, and for the preservation of historical names.
Hatert, Frédéric ; ; et al
in European Journal of Mineralogy (2013), 25Detailed reference viewed: 1 (0 ULg)
Rapid Plant Invasion in Distinct Climates Involves Different Sources of Phenotypic Variation
Monty, Arnaud ; Bizoux, Jean-Philippe ; et al
in PLoS ONE (2013), 8(1), 55627
When exotic species spread over novel environments, their phenotype will depend on a combination of different processes, including phenotypic plasticity (PP), local adaptation (LA), environmental maternal ... [more ▼]
When exotic species spread over novel environments, their phenotype will depend on a combination of different processes, including phenotypic plasticity (PP), local adaptation (LA), environmental maternal effects (EME) and genetic drift (GD). Few attempts have been made to simultaneously address the importance of those processes in plant invasion. The present study uses the well-documented invasion history of Senecio inaequidens (Asteraceae) in southern France, where it was introduced at a single wool-processing site. It gradually invaded the Mediterranean coast and the Pyrenean Mountains, which have noticeably different climates. We used seeds from Pyrenean and Mediterranean populations, as well as populations from the first introduction area, to explore the phenotypic variation related to climatic variation. A reciprocal sowing experiment was performed with gardens under Mediterranean and Pyrenean climates. We analyzed climatic phenotypic variation in germination, growth, reproduction, leaf physiology and survival. Genetic structure in the studied invasion area was characterized using AFLP. We found consistent genetic differentiation in growth traits but no home-site advantage, so weak support for LA to climate. In contrast, genetic differentiation showed a relationship with colonization history. PP in response to climate was observed for most traits, and it played an important role in leaf trait variation. EME mediated by seed mass influenced all but leaf traits in a Pyrenean climate. Heavier, earlier-germinating seeds produced larger individuals that produced more flower heads throughout the growing season. However, in the Mediterranean garden, seed mass only influenced the germination rate. The results show that phenotypic variation in response to climate depends on various ecological and evolutionary processes associated with geographical zone and life history traits. Seeing the relative importance of EME and GD, we argue that a “local adaptation vs. phenotypic plasticity” approach is therefore not sufficient to fully understand what shapes phenotypic variation and genetic architecture of invasive populations. [less ▲]Detailed reference viewed: 14 (5 ULg)
Cartographie des Emissions annuelles de CO2 dues aux consommations énergétiques des bâtiments tertiaires en Région wallonne. Rapport de synthèse.
Barbason, Mathieu ; Reiter, Sigrid
Report (2013)Detailed reference viewed: 17 (1 ULg)
Structural Behavior of Concrete Columns under Natural Fires
Gernay, Thomas ;
in Engineering Computations (2013), 30(6),
Purpose - The paper aims to give an insight into the behavior of reinforced concrete columns during and after the cooling phase of a fire. The study is based on numerical simulations as these tools are ... [more ▼]
Purpose - The paper aims to give an insight into the behavior of reinforced concrete columns during and after the cooling phase of a fire. The study is based on numerical simulations as these tools are frequently used in structural engineering. As the reliability of numerical analysis largely depends on the validity of the constitutive models, the development of a concrete model suitable for natural fire analysis is addressed in the study. Design/methodology/approach - The paper proposes theoretical considerations supported by numerical examples to discuss the capabilities and limitations of different classes of concrete models and eventually to develop a new concrete model that meets the requirements in case of natural fire analysis. Then, the study performs numerical simulations of concrete columns subjected to natural fire using the new concrete model. A parametric analysis allows for determining the main factors that affect the structural behavior in cooling. Findings – Failure of concrete columns during and after the cooling phase of a fire is a possible event. The most critical situations with respect to delayed failure arise for short fires and for columns with low slenderness or massive sections. The concrete model used in the simulations is of prime importance and the use of the Eurocode model would lead to unsafe results. Practical implications – The paper includes implications for the assessment of the fire resistance of concrete elements in a performance-based environment. Originality/value – The paper provides original information about the risk of structural collapse during cooling. [less ▲]Detailed reference viewed: 42 (16 ULg)
Methodology for the Validation of Analytical Methods involved in Uniformity of Dosage Units tests
Rozet, Eric ; Ziemons, Eric ; Marini Djang'Eing'A, Roland et al
in Analytica Chimica Acta (2013), 760
Validation of analytical methods is required prior to their routine use. In addition, the current implementation of the Quality by Design (QbD) framework in the pharmaceutical industries aims at improving ... [more ▼]
Validation of analytical methods is required prior to their routine use. In addition, the current implementation of the Quality by Design (QbD) framework in the pharmaceutical industries aims at improving the quality of the end products starting from its early design stage. However, no regulatory guideline or none of the published methodologies to assess method validation propose decision methodologies that effectively take into account the final purpose of developed analytical methods. In this work a solution is proposed for the specific case of validating analytical methods involved in the assessment of the Content Uniformity or Uniformity of Dosage Units of a batch of pharmaceutical drug products as proposed in the European or US pharmacopoeias. This methodology uses statistical tolerance intervals as decision tools. Moreover it adequately defines the Analytical Target Profile of analytical methods in order to obtain analytical methods that allow to make correct decisions about Content Uniformity or Uniformity of Dosage Units with high probability. The applicability of the proposed methodology is further illustrated using an HPLC-UV assay as well as a Near Infra-Red Spectrophotometric method. [less ▲]Detailed reference viewed: 39 (10 ULg)
Interleukin-32 expression is associated with a poorer prognosis in head and neck squamous cell carcinoma.
; Mouallif, Mustapha ; Hubert, Pascale et al
in Molecular Carcinogenesis (2013)
Head and neck squamous cell carcinoma (HNSCC) represent the sixth most common malignancy diagnosed worldwide. Patient's survival is low due the high frequency of tumor recurrence. Inflammation promotes ... [more ▼]
Head and neck squamous cell carcinoma (HNSCC) represent the sixth most common malignancy diagnosed worldwide. Patient's survival is low due the high frequency of tumor recurrence. Inflammation promotes carcinogenesis as well as the formation of metastasis. Indeed, proinflammatory mediators are known to stimulate the expression of specific transcription factors such as Snai1 and to increase the ability of tumor cells to migrate into distant organs. The atypical interleukin-32 (IL32) was mainly described to exacerbate inflammatory responses in rheumatoid arthritis and inflammatory bowel diseases. IL32 is expressed in various cancers but its role in HNSCC physiology is still unexplored. Here, we analyzed the expression of IL32 and its implication on HNSCC aggressiveness. We showed that patients with tumor expressing high amounts of IL32 exhibit decreased disease-free periods (20.5 mo vs. 41 mo, P = 0.0041) and overall survival (P = 0.0359) in comparison with individuals with weak IL32 tumor expression. This overexpression was negatively correlated with gender (P = 0.0292) and p53 expression (P = 0.0307). In addition, in vitro data linked IL32 expression to metastasis formation since IL32 inhibition decreased Snai1 expression and tumor cell migration in a Boyden chamber assay. Our data provide new insight into the role of IL32 in HNSCC aggressiveness. (c) 2013 Wiley Periodicals, Inc. [less ▲]Detailed reference viewed: 17 (4 ULg)