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See detailImaging the mechanisms involved in abdominal aortic aneurysms rupture; a step towards patient-specific risk assessment
NCHIMI LONGANG, Alain ULg

Doctoral thesis (2015)

Introduction The general context of this dissertation is to evaluate patient-specifi c approaches to the risk of rupture of abdominal aortic aneurysm (AAA), using imaging techniques with ability to assess ... [more ▼]

Introduction The general context of this dissertation is to evaluate patient-specifi c approaches to the risk of rupture of abdominal aortic aneurysm (AAA), using imaging techniques with ability to assess biological processes. Following a thorough description of available imaging techniques, our work is divided in two main research objectives, namely: (i) to provide greater clinical value to existing but unproven imaging concepts, and (ii) to suggest new concepts for improved AAA risk of rupture assessment. Methods The fi rst research objective evaluated how far imaging biological activities using 18F-Fluorodeoxyglucose (FDG) Positron Emission Tomography (PET) and modeling wall stress using fi nite element simulations (FES) may help clinical decisionmaking in patients with AAA, and what would be their incremental value as compared to diameter-based patient management algorithms. On a patient basis, clinical outcomes were evaluated with regard to FDG PET and FES signaling. Further, the concept of AAA risk-equivalent diameter using FES was described and retrospectively validated using data from large multicenter trials. The second research objective included the assessment of the biological activities of the intraluminal thrombus (ILT) and the demonstration of its deleterious role in AAA using multimodality imaging. A special emphasis was put on the ability of magnetic resonance imaging (MRI) to monitor the biological activities of ILT without exogenous contrast, by evaluating its iron content. Results Increased FDG uptake was a diameter-independent marker of AAA-related events over 2 years. Missing dichotomy prevented such a fi nding for increased wall stress, although its correlation with increased FDG uptake indicates a potentially comparable value in terms of risk management. Wall metabolism is infl uenced by patient-specifi c susceptibility factors, indicating hereditary or acquired alteration of the biological responses to wall stress. The concept of risk-equivalent diameters on FES links biomechanical estimates to basic conclusions drawn from large diameter-based clinical AAA trials. Our retrospective and diameter-adjusted validation analysis verifi ed that biomechanical risk indicators are higher in ruptured than non-ruptured AAAs. Part of the FDG uptake is associated with biological activity along the luminal surface of the ILT, where we experimentally demonstrated phagocytosis of superparamagnetic iron oxide on MRI , both ex vivo and in vivo. This phagocytosis is correlated with the abundance of leukocytes and proteolytic activity. In addition, unenhanced MRI appearances resulting from the endogenous iron distribution within ILT also relate to these biological activities. Lastly, multimodality imaging was used to confi rm the concept of the deleterious role of the ILT in AAA growth in a model of AAA by infusion of elastase in the rat. Conclusion MRI and FDG PET are capable of evidencing and quantifying in vivo some of the notoriously deleterious biological processes taking place in the aneurysmal sac, especially related to the entrapped phagocytes and red blood cells in ILT and the periadventitial infl ammatory response. The central role played by ILT and its biological activities was demonstrated in vivo using several imaging techniques. The clinical value of imaging these biological activities is epitomized by a diameterindependent 2-year increased risk of event in AAA with increased wall metabolism. [less ▲]

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See detailSome misunderstood or unknown LaTeX tricks (XVI)
Merciadri, Luca ULg

E-print/Working paper (2015)

This is the second (and last) part of the tricks I found on StackExchange. First part began in the preceding issue. We will begin by a personal trick, and end by some inquiry about my LaTeX Tips & Tricks.

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See detailSome misunderstood or unknown LaTeX tricks (XV)
Merciadri, Luca ULg

E-print/Working paper (2015)

After having looked at about 150 StackExchange pages of 50 topics (that sums up to about 7500 topics’ names), I give you, in this article and in the next issue, the most interesting topics’ answers to my ... [more ▼]

After having looked at about 150 StackExchange pages of 50 topics (that sums up to about 7500 topics’ names), I give you, in this article and in the next issue, the most interesting topics’ answers to my eyes. We will first begin by two additions in regard to 31(3), 32(1). [less ▲]

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See detailZones humides : entre modifications environnementales et actions humaines
Ozer, Pierre ULg

Conference (2015, February 08)

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See detailQuand science politique et droit dialoguent : quelle typologie des instruments mémoriels en fonction du degré de contrainte ?
Grandjean, Geoffrey ULg

Conference (2015, February 07)

Envisager les études sur la mémoire comme sous-champ de la science politique francophone ouvre des pistes enrichissantes pour les politologues, notamment lorsqu’ils sont amenés à analyser les instruments ... [more ▼]

Envisager les études sur la mémoire comme sous-champ de la science politique francophone ouvre des pistes enrichissantes pour les politologues, notamment lorsqu’ils sont amenés à analyser les instruments mémoriels régissant un ou plusieurs système(s) politique(s). Dans cette perspective, la communication vise à présenter, d’un point de vue épistémologique, les apports découlant de l’interaction entre les sciences politique et juridique dans le processus de consolidation des études sur la mémoire comme sous-champ disciplinaire de la science politique. Plus précisément, la communication vise à offrir une typologie des instruments mémoriels en fonction du degré de contrainte et d’imposition d’une mémoire officielle. Par exemple, une résolution adoptée par une assemblée législative est faiblement contraignante alors qu’une loi réprimant le négationnisme impose à la fois une mémoire officielle tout en sanctionnant pénalement les citoyens qui ne la respectent pas. La typologie passe en revue les multiples instruments mémoriels pouvant être adoptés par les autorités publiques : résolution, loi déclarative, loi pénale, plan de commémorations ou encore mise en valeur d’un lieu de mémoire. L’accent est mis sur les instruments mémoriels de deux pays francophones : la Belgique et la France. Au final, cette communication permet d’insister sur l’apport de la science politique en analysant l’exercice de prérogatives de puissance publique et sur l’apport de la science juridique en classifiant les types d’instruments mémoriels en fonction du degré de contrainte ; tout en faisant dialoguer des cas d’étude différents. [less ▲]

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See detailThe return of Turkey to the Western Balkans: a challenge or an opportunity for the European Union ?
Lika, Liridon ULg

Conference (2015, February 07)

In the new Turkish doctrine, besides the great interests in Central Asia, Middle East, Africa and the Caucasus, the Balkans are also important. Turkey is making great efforts to play a greater role on the ... [more ▼]

In the new Turkish doctrine, besides the great interests in Central Asia, Middle East, Africa and the Caucasus, the Balkans are also important. Turkey is making great efforts to play a greater role on the international scene and creates its area of interest, especially where the links of Ottoman legacy can help. Although it is defined as a peaceful power in the region, some describe it as neo-ottoman, a term rejected by the Turkish authorities because of its possible imperialist connotation. This paper aims precisely to study the return of Turkey to the Balkans. Our central question is: what is the purpose of the Turkish foreign policy in the Western Balkans? Related issues will be addressed such as: is there a competition between Turkey and the European Union in this area? What are the specifics of Turkish foreign policy? In order to explore these research questions, this study focuses on the concept of soft power through which Turkey extends its power. Indeed, the Turkish government imposes itself on the Balkans not by force but with the help of economics, diplomacy, trade, culture and religion. Following the crisis in the EU, causing the collapse of Western investment and a relative decrease of attraction for the Balkans, Turkey has taken advantage of the situation in order to increase its influence in all areas. This contribution will proceed in three stages. Firstly, we will make an analysis of the authors of soft power to think about the character of the new Turkish geopolitical doctrine. Secondly, we are going to apply this theoretical framework to the case study identified, namely the influence of Turkey in the Western Balkan countries. Finally, we will show if exists a competition or a cooperation between Turkey and European Union in the Western Balkans. [less ▲]

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See detailIn situ investigation of scCO2 assisted impregnation of drug into polymer by high pressure FTIR micro-spectroscopy
Champeau, Mathilde ULg; Thomassin, Jean-Michel ULg; Jérôme, Christine ULg et al

in Analyst (2015), 140(3), 869-879

An original experimental set-up combining a FTIR microscope with a high pressure cell has been built in order to analyze in-situ the impregnation of solute into microscopic polymer samples, such as fibers ... [more ▼]

An original experimental set-up combining a FTIR microscope with a high pressure cell has been built in order to analyze in-situ the impregnation of solute into microscopic polymer samples, such as fibers or films, subjected to supercritical CO2. Thanks to this experimental set-up, key factors governing the impregnation process can be simultaneously followed such as the swelling of the polymeric matrix, the CO2 sorption, the kinetic of impregnation and the drug loading into the matrix. Moreover, the solute/polymer interactions and the speciation of the solute can be analyzed. We have monitored in situ the impregnation of aspirin and ketoprofen into PEO (Polyethylene Oxide) platelets at T=40°C and P=5; 10 and 15 MPa. The kinetic of impregnation of aspirin was quicker than the one of ketoprofen and the final drug loading was also higher in case of aspirin. Whereas the CO2 sorption and the PEO swelling remain constant when PEO is just subjected to CO2 under isobaric conditions, we noticed that both parameters can increase while the drug impregnates PEO. Coupling these results with DSC measurements, we underlined the plasticizing effect of the drug that also leads to decrease the crystallinity of PEO in situ thus favoring the sorption of CO2 molecules into the matrix and the swelling of the matrix. The plasticizing effect increases with the drug loading. Finally, the speciation of drug was investigated considering the shift of the carboxyl bands of the drugs. Both drugs were found to be mainly homogeneously dispersed into PEO. [less ▲]

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See detailLa pérennisation des partenariats publics-privés dans le champ de l’emploi : entre application, interprétation et ajustement du cadre réglementaire
Remy, Céline ULg; Gérard, Julie ULg; Beuker, Laura ULg

Conference (2015, February 07)

Dans une perspective de gestion mixte du marché du travail, les services publics de l’emploi sont invités, par la Convention 181 de l’OIT de 1997, à déléguer et à confier l’exploitation et la gestion de ... [more ▼]

Dans une perspective de gestion mixte du marché du travail, les services publics de l’emploi sont invités, par la Convention 181 de l’OIT de 1997, à déléguer et à confier l’exploitation et la gestion de leurs activités à des opérateurs privés de service, dans le cadre d’une entente contractuelle. Alors que les modalités de la collaboration (telles que le public-cible, le type et le nombre d’accompagnements dispensés, les résultats à atteindre, etc.) sont fixées, initialement, par les services publics de l’emploi, elles sont ensuite mises en pratique par les diverses parties-prenantes du partenariat. Les acteurs publics et privés exploitent la part de latitude inhérente à leur fonction pour interpréter et ajuster les termes du contrat ou pour pouvoir réaliser leur mission d’accompagnement des demandeurs d’emploi. Partant du postulat que la règle est incomplète, notre objectif est d’analyser la mise en œuvre du partenariat en saisissant les arguments avancés par les acteurs pour justifier et légitimer leurs actions. À partir de cette analyse, nous montrerons que les acteurs du partenariat doivent interpréter les règles – écart entre le travail prescrit et le travail effectivement presté – dans leurs pratiques quotidiennes. Agissant comme des « pseudo » street-level bureaucrats, ces derniers usent de leur pouvoir pour ajuster les règles. En outre, il semblerait que ces pratiques d'indiscipline permettent, en réalité, de maintenir les relations partenariales entre services publics de l’emploi et opérateurs privés, et d’œuvrer, in fine, à la pérennisation de celles-ci dans le champ de l’emploi. Nous appuierons notre analyse sur un matériau empirique composé d’observations participantes et d’entretiens semi-directifs réalisés auprès des parties-prenantes des PPP, situés en Belgique francophone. [less ▲]

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See detailA novel mutation of the luteinizing hormone/choionic gonadotrophin receptor gene leading to Leydig cell hypoplasia type I
Potorac, Iulia ULg; Rivero-Müller, A; Pintiaux, Axelle ULg et al

in Symposium "Perspectives in Endocrinology" - 5ème édition (2015, February 07)

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See detailIntérêt du signal T2 des adénomes hypophysaires à GH traités par analogues de la somatostatine - premiers résultats de l'étude IRMA#2
Potorac, Iulia ULg; PETROSSIANS, Patrick ULg; Daly, Adrian ULg et al

in Symposium "Perspectives in Endocrinology" - 5ème édition (2015, February 07)

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See detailNouvelle classification des acro-gigantismes
Rostomyan, Liliya ULg; Beckers, Albert ULg

in Symposium "Perspectives in Endocrinology" - 5ème édition (2015, February 07)

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See detailRevisiting the SN1987A gamma-ray limit on ultralight axion-like particles
Payez, Alexandre ULg; Evoli, Carmelo; Fischer, Tobias et al

in Journal of Cosmology and Astroparticle Physics [= JCAP] (2015), 2015(02), 006

We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and ... [more ▼]

We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and eventually convert into gamma rays in the magnetic field of the Milky Way. The lack of a gamma-ray signal in the GRS instrument of the SMM satellite in coincidence with the observation of the neutrinos emitted from SN1987A therefore provides a strong bound on their coupling to photons. Due to the large uncertainty associated with the current bound, we revise this argument, based on state-of-the-art physical inputs both for the supernova models and for the Milky-Way magnetic field. Furthermore, we provide major amendments, such as the consistent treatment of nucleon-degeneracy effects and of the reduction of the nuclear masses in the hot and dense nuclear medium of the supernova. With these improvements, we obtain a new upper limit on the photon-ALP coupling: g_{a\gamma} < 5.3 x 10^{-12} GeV^{-1}, for m_a < 4.4 x 10^{-10} eV, and we also give its dependence at larger ALP masses. Moreover, we discuss how much the Fermi-LAT satellite experiment could improve this bound, should a close-enough supernova explode in the near future. [less ▲]

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See detailSingle Wavelength Coarse Phasing In Segmented Telescopes
Simar, Juan Felipe ULg

in Applied Optics (2015), 54

Space observations of fainter and more distant astronomical objects constantly require telescope primary mirrors with a larger size. The diameter of monolithic primary mirrors is limited to 10 m because ... [more ▼]

Space observations of fainter and more distant astronomical objects constantly require telescope primary mirrors with a larger size. The diameter of monolithic primary mirrors is limited to 10 m because of manufacturing limitations. For space telescopes, the primary mirrors are limited to less than 5 m due to fairing capacity. Segmented primary mirrors thus constitute an alternative solution to deal with the steadily increase of the primary mirror size. The optical path di erence between the individual segments must be close to zero (few nm) in order to be di raction limited. We propose in this paper a new inter-segment piston sensor based on coherence measurement of a star image. This sensor is intended to be used in the co-phasing system of future segmented mirrors. [less ▲]

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See detailComment les disciplines se reconstruisent dans des environnements hybrides et dynamiques
Fallon, Catherine ULg; Thoreau, François ULg

Scientific conference (2015, February 06)

Les chercheurs en sciences politiques et sociales, voire les philosophes politiques, sont de plus en plus souvent « embarqués » dans des projets résolument transdisciplinaires, portés par les groupes de ... [more ▼]

Les chercheurs en sciences politiques et sociales, voire les philosophes politiques, sont de plus en plus souvent « embarqués » dans des projets résolument transdisciplinaires, portés par les groupes de recherche de différentes disciplines, engagés dans les développement scientifico-technologiques les plus pointus, que ce soit dans le secteur des nanotechnologies ou des biotechnologies médicales (pour citer deux exemples récents,Thoreau 2013) . Cet article prend comme point de départ un projet pluriannuel qui a obtenu des subsides pour plonger pendant une longue période trois chercheurs (philosophe, anthropologue, politologue) dans un centre de recherche en génomique humaine appliquée, installé dans une aile du Centre-Hospitalo-Universitaire. En tant que coordinateurs de ce projet, nous voulons aborder ab initio (1) la question des conditions d’exercice de notre démarche de terrain et (2) les conditions de notre service en tant que politologues au fil de cette trajectoire. [less ▲]

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See detailComprendre les programmes électoraux : comparaison des méthodes d’encodage manuel et automatique
Piet, Grégory ULg; Dandoy, Régis; Joly, Jeroen

Conference (2015, February 06)

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See detailMédias et dette wallonne: polémique autour d'un indicateur de finances publiques
Piron, Damien ULg

Conference (2015, February 06)

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See detailA mixed integer nonlinear programming bi-objective model for intermodal network design
Mostert, Martine ULg; Caris, An; Limbourg, Sabine ULg

Conference (2015, February 05)

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See detailOpinions, attitudes et comportements politiques. Notes de cours
Grandjean, Geoffrey ULg

Learning material (2015)

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