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See detailIntroduction au séminaire
Francois, Jeromine ULg; Regibeau, Julien ULg

Conference (2016, March 09)

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See detailAdaptive versus linear testing: selected examples from psychology, education and medicine
Magis, David ULg

Scientific conference (2016, March 08)

Most often data from psychological, educational or medical research are collected by administering questionnaires to the participants. Such questionnaires are usually made of the same set of items (i.e ... [more ▼]

Most often data from psychological, educational or medical research are collected by administering questionnaires to the participants. Such questionnaires are usually made of the same set of items (i.e. questions) and are designed to precisely target the studied latent trait: this is referred to as "linear testing". However, linear testing can be counterproductive in some specific situations. For instance, not all items can accurately target the latent trait (e.g., "easy" items are not informative for "highly able" participants), so that the duration of the test can be uselessly extended. Adaptive testing is an emerging paradigm that aims at selecting and administering each item on the basis of previously selected items and the responses of the participants. The selectuion of the item is made optimally so that the most informative item for the respondent is chosen. This permits, among others, to better target the true latent trait to be estimated, shortening then the test duration. In this talk, linear and adaptive testing will be sketched from an educational testing approach. Then, selected examples from the psychological, educational and medical litterature will be briefly reviewed to illustrate the potentially usefulness of adaptive testing. Pros and cons of this method will also be outlined. [less ▲]

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See detailExtinction of fish-shaped marine reptiles associated with reduced evolutionary rates and global environmental volatility
Fischer, Valentin ULg; Bardet, Nathalie; Benson, Roger et al

in Nature Communications (2016), 7(10825), 1-11

Despite their profound adaptations to the aquatic realm and their apparent success throughout the Triassic and the Jurassic, ichthyosaurs became extinct roughly 30 million years before the end-Cretaceous ... [more ▼]

Despite their profound adaptations to the aquatic realm and their apparent success throughout the Triassic and the Jurassic, ichthyosaurs became extinct roughly 30 million years before the end-Cretaceous mass extinction. Current hypotheses for this early demise involve relatively minor biotic events, but are at odds with recent understanding of the ichthyosaur fossil record. Here, we show that ichthyosaurs maintained high but diminishing richness and disparity throughout the Early Cretaceous. The last ichthyosaurs are characterized by reduced rates of origination and phenotypic evolution and their elevated extinction rates correlate with increased environmental volatility. In addition, we find that ichthyosaurs suffered from a profound Early Cenomanian extinction that reduced their ecological diversity, likely contributing to their final extinction at the end of the Cenomanian. Our results support a growing body of evidence revealing that global environmental change resulted in a major, temporally staggered turnover event that profoundly reorganized marine ecosytems during the Cenomanian. [less ▲]

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See detailUtilisation dans QGIS des Web Map Services (WMS) du Géoportail de Wallonie
Lejeune, Philippe ULg; Handerek, Daphné

Cartographic material (2016)

Note technique expliquant comment accéder aux Webservices du géoportail de Wallonie avec le logiciel QGIS. Ce guide est accompagné d'un projet QGIS rassemblant les WMS les plus utiles (ortho-images ... [more ▼]

Note technique expliquant comment accéder aux Webservices du géoportail de Wallonie avec le logiciel QGIS. Ce guide est accompagné d'un projet QGIS rassemblant les WMS les plus utiles (ortho-images, cadastre, fond topographique, plans de secteurs) [less ▲]

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See detailDes styles historiques à l'Art nouveau
Charlier, Sébastien ULg

Conference given outside the academic context (2016)

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See detailUnfolding Time with Gail Jones: an Interview
Belleflamme, Valérie-Anne ULg

Diverse speeche and writing (2016)

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See detailSpecialization SIAMU : past, present and future
Servotte, Jean-Christophe ULg

Conference (2016, March 08)

Présentation de l'histoire de la spécialisation SIAMU avec un focus sur la simulation.

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See detailAOP/IGP : Gage d'origine et de spécificités ?
Tielemans, Magali ULg; Sindic, Marianne ULg

Conference given outside the academic context (2016)

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See detailMOOCs in business administration - An overview of assessment practice
Gherib, Camelia; Dujardin, Jean-Marie ULg; Verpoorten, Dominique ULg

in Proceedings of the Conference of the European Association for Practitioner Research on Improving Learning (EAPRIL) 2015, Issue 2 (2016, March 07)

The study explores 31 MOOCs in the field of business administration, equipped with a conceptual framework documenting 18 facets of assessment design. As a second step, the data collected on 3 MOOCs about ... [more ▼]

The study explores 31 MOOCs in the field of business administration, equipped with a conceptual framework documenting 18 facets of assessment design. As a second step, the data collected on 3 MOOCs about assessment is submitted to university members in charge of external courses accreditation procedures in order to ascertain its possible influence on their decision to credit a MOOC or not. Main results indicate that, a) the typical profile of the assessment procedure for MOOCs in business administration is: QCM-based, automatic, continuous, individual, product-centred, standardized, b) secure ways (proctoring, test-centres) to warrant learners’ identity for the tests can already be found in some MOOCs of this field, and c) concerns of course accreditors bear first and foremost on these student authentication aspects. [less ▲]

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See detailLa 3D : la technologie qui a changé l'histoire du monde
Verly, Jacques ULg

Conference given outside the academic context (2016)

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See detailPerformance variation of common ragweed (Ambrosia artemisiifolia L.) across invasion levels in Western Europe
Ortmans, William ULg; Mahy, Grégory ULg; Chauvel, Bruno et al

in Flora (2016), 220

The occurrence of an invasive plant across a continent is generally not homogeneous; typically, some areas are highly invaded whereas others show moderate or low invasion levels. This situation might be a ... [more ▼]

The occurrence of an invasive plant across a continent is generally not homogeneous; typically, some areas are highly invaded whereas others show moderate or low invasion levels. This situation might be a snapshot of an ongoing spread, but it could also remain stable under the pressure of factors that constrain the invasion. Among those factors, plant performance variation among invasion levels can explain an invasion slowdown. However, few studies have investigated the large-scale variation of invasive plant performance in the field. Ambrosia artemisiifolia L. in Western Europe represents a good opportunity to address this issue, with areas of high, moderate and low invasion levels being documented across a ca. 1000 km transect. In this study, we compared in situ plant performance-related traits in 12 populations from areas of contrasting invasion levels. We also tested whether performance-related traits were influenced by the intra-and inter-specific competition, by the local climatic conditions or by latitude (a proxy for growing season length). Overall, we did not find differences in performance-related traits across invasion levels, and intra-and inter-specific competition had low effects on plant performance. This study highlights the fact that A. artemisiifolia individuals express similar performance across invasion levels, even beyond what can be considered the present invasion front. Further research has to expand this study northwards, and assess other factors that could constrain the invasion in order to highlight if the species invasion northward is constrained or if it has the potential to invade new areas. [less ▲]

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See detailUNESCO et politique international de la culture : histoire de la diversité culturelle
Vlassis, Antonios ULg

Scientific conference (2016, March 07)

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See detailPerformance of a radial-inflow turbine integrated in an ORC system and designed for a WHR on truck application: An experimental comparison between R245fa and R1233zd
Guillaume, Ludovic ULg; Legros, Arnaud ULg; Desideri, Adriano ULg et al

in Applied Energy (2016)

The goal of this study is to experimentally compare the performance of an Organic Rankine Cycle (ORC) system equipped with a radial-inflow turbine for two working fluids: R245fa and R1233zd. The radial ... [more ▼]

The goal of this study is to experimentally compare the performance of an Organic Rankine Cycle (ORC) system equipped with a radial-inflow turbine for two working fluids: R245fa and R1233zd. The radial- inflow turbine is a small-scale prototype designed to convert the waste heat from the exhaust gases of a truck combustion engine and was developed mainly using components of truck turbochargers. It is directly connected to a high-speed synchronous generator. The bearings system of the turbine and the generator have the innovative particularity to be respectively lubricated and cooled down by the working fluid so no additional lubricant or coolant is needed. The experimental comparison is carried out over a test-rig equipped with the radial turbine. The heat wasted by the truck through the exhaust gases is sim- ulated using an electric oil boiler coupled to the ORC loop. The electrical power supplied by the turbine, limited to a maximum of 3.5 kWel by the generator, is then dissipated in a load bank composed of truck fans while the condenser is cooled by a water loop. Measurements in steady-state are performed in order to evaluate the performance of the turbine-generator set when varying the pressure ratio, the rotational speed, the inlet temperature and the mass flow rate of the turbine and the lubrication flow rate of the bearings for various oil temperatures and mass flow rates. In order to identify the most suitable fluid for the Waste Heat Recovery (WHR) application, three comparison methods are proposed and discussed based on the measurements. Finally, because the turbine-generator set is the first oil-free prototype developed by the manufacturer, potential sources of improvements are discovered and discussed. [less ▲]

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See detailDynamic calibration of piezoelectric transducers for ballistic high-pressure measurement
Elkarous, Lamine ULg; Robbe, Cyril; Pirlot, Marc et al

in International Journal of Metrology and Quality Engineering (2016)

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See detailLe casier judiciaire : un instrument mémoriel au passé tourmenté mais à l’avenir empreint de sérénité ?
Seron, Vincent ULg

in Journal des Tribunaux (2016)

Profondément réformé en 1997, le casier judiciaire n’en finit pas de faire l’objet de remaniements et de prêter le flanc à la critique. Des modifications régulièrement opérées s’agissant de la délivrance ... [more ▼]

Profondément réformé en 1997, le casier judiciaire n’en finit pas de faire l’objet de remaniements et de prêter le flanc à la critique. Des modifications régulièrement opérées s’agissant de la délivrance de ses extraits à sa mise à jour lacunaire, nombreux sont les éléments qui témoignent des difficultés récurrentes auxquelles cet instrument séculaire est confronté. En quatre temps, cet article propose de remettre en perspective les principaux éléments explicatifs de l’état transitoire au sein duquel le casier judiciaire est confiné depuis près de deux décennies, d’analyser son fonctionnement actuel, de focaliser l’attention sur les récents changements apportés à son contenu ainsi qu’à la communication des données qu’il contient, et de s’interroger sur la prétendue non fiabilité de ce casier. [less ▲]

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See detailPropositions pour penser la notion d'erreur en photographie
Havelange, Carl ULg

Conference (2016, March 04)

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See detailRepeated Behavioral Assessments in Patients with Disorders of Consciousness
Wannez, Sarah ULg; Annen, Jitka ULg; Aubinet, Charlène ULg et al

Conference (2016, March 04)

The Coma Recovery Scale Revised (CRS-R) is considered as the most sensitive scale to assess patients with disorders of consciousness (DOC). Guidelines recommend repeated assessments because patients might ... [more ▼]

The Coma Recovery Scale Revised (CRS-R) is considered as the most sensitive scale to assess patients with disorders of consciousness (DOC). Guidelines recommend repeated assessments because patients might suffer from consciousness fluctuations, but it is not specified how many assessments are needed. The present study included 131 patients with DOC. They have been assessed at least 6 times during a 14-days period with the CRS-R. Results show that 5 CRS-R assessments are needed to reach a reliable diagnosis, and that all the CRS-R subscales are influenced by consciousness fluctuations. We here showed that consciousness fluctuations influence the behavioral diagnosis, and that 5 assessments within a short period of time are needed to get a reliable clinical diagnosis. [less ▲]

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See detailEpidemiological Study of Canine Leishmaniasis in Algeria and its Impact on the Human Visceral Leishmaniasis
Adel, Amal ULg

Doctoral thesis (2016)

Zoonotic visceral leishmaniasis (VL), caused by Leishmania infantum is a vector-borne disease, transmitted to humans by the bite of infected female phlebotomine sand flies. In absence of treatment the ... [more ▼]

Zoonotic visceral leishmaniasis (VL), caused by Leishmania infantum is a vector-borne disease, transmitted to humans by the bite of infected female phlebotomine sand flies. In absence of treatment the outcome is death. The disease is characterised by irregular fever bouts, loss of weight, hepatosplenomegaly and anaemia. It is endemic in the Indian sub-continent and in East Africa. In the Mediterranean region, it is present in rural areas, in villages, in mountain areas, but also in certain peri-urban zones, where the parasites survive in dogs and other mammals. In fact, domestic dogs are the principal reservoir of human VL and they also can develop a more generalised and fatal form of the disease, although more than half of the dogs remain asymptomatic, the individual outcome depending on both cellular and humoral immune responses. Both symptomatic and asymptomatic dogs can infect the phlebotomine vectors, thereby enabling the transmission to other dogs or to people. This is the main reason why early detection and treatment of infected animals is the best way to reduce the risk of infection and, as such, forms an essential component in the prevention and control of the human disease. Ideally, a so-called “gold standard” test is required to reliably and correctly determine the infectious status of an individual and/or the infection prevalence in a population in a certain region at a certain point in time. A gold-standard test provides an error-free classification of individuals as infected or infection-free. The discriminative power of a real-life test is quantified by measures of precision, more specifically the sensitivity and the specificity of the test. They vary in function of characteristics of the population studied. In the majority of cases, a gold standard test does not exist. In order to overcome this lack, use is made of reference tests. The latter are often imperfect (sensitivity and specificity below one) and they allow estimation of a so-called apparent prevalence rather than the actual true prevalence. A statistical solution to the problem of lack of gold standard test consists of a Bayesian approach, which allows us to combine data of a study with external (prior, independent) information, such as results from previous studies or expert opinion. This approach yields an estimate of the true prevalence, as well as estimates of the sensitivity and specificity of the tests used. This thesis attempts to contribute towards a better understanding of the epidemiology of visceral leishmaniasis in Algeria. More specifically, our general objective (Chapter 3) was to estimate the true prevalence of canine leishmaniasis, in a situation where a diagnostic gold standard test was unavailable, and to describe the epidemiological curve and profile of visceral leishmaniasis in the country. With this in mind, the work is organised in nine chapters. The first chapter outlines the importance of leishmaniasis (respectively visceral and canine) in terms of public health and veterinary public health and provides an overview of the current knowledge base on canine leishmaniasis. The second chapter is devoted to a description of the epidemiological methodology available for the estimation of the true prevalence and the test characteristics in the absence of gold standard test. Chapter 4 describes an epidemiological study conducted in the capital city Algiers, comprising 462 dogs subdivided in four groups according to their function (stray dogs, guard dogs, farm dogs and pet dogs). A Bayesian approach was used to estimate the true prevalence of canine leishmaniasis in the four groups and to evaluate three serological tests: an indirect immunofluorescence test (IFAT), a direct agglutination test (DAT) and a commercial rapid test on gel, based on the protein rK39 (PaGIA). We were able to demonstrate variability in the test performance characteristics in the different groups, and this in terms of sensitivity and specificity. IFAT, although it is an imperfect test, is nevertheless the test of choice when the dog population targeted consists of stray dogs, but its specificity drops to a unsatisfactory 65.2% (IC: 60.2-73.5%) when applied to farm dogs: the fact of living together with other animals may induce cross-reactions. Stray dogs also yielded the highest estimate for the true prevalence (11.7%), probably a consequence of their constant living outside, which increases the risk of exposure to infected phlebotomine vectors. Using the above results, a large-scale transversal survey was mounted in six towns of the littoral zone of Algeria (Chapter 5). Thus, a total of 2,184 farm dogs and guard dogs were sampled in two distinct periods using two serological tests: before and after the main vector season, using IFAT and DAT. Serial and parallel interpretation of the combined tests were compared to various other statistical methods in order to estimate the true prevalence and the sensitivity and specificity of the two tests. The latent class model of Hui and Walter based on conditional independence between the diagnostic tests was compared to a Bayesian model, which made it possible to include conditional dependency between tests, if required. The best-adjusted model estimated canine leishmaniasis prevalence between 11% and 38% with an increasing trend from west to east. IFAT sensitivity varied between 86% and 88% in the different localities, whereas specificity ranged between 65% and 87%. DAT was invariably less sensitive than IFAT, but had a better specificity: between 80% and 95% in function of locality and season. The results highlighted once more the danger of considering IFAT to be a gold standard test for canine leishmaniasis. Chapter 6 draws up an epidemiological profile of human zoonotic visceral leishmaniasis in Algeria, based on cases notified to the National Public Health Institute between 1998 and 2008. A total of 1,562 were found for this period. This translates into an incidence rate of 0.45 cases per 100,000 inhabitants, of which 81.4% were children between zero and four years of age. Splenomegaly, fever, pallor and pancytopenia were the principal clinical and biochemical signs. Antimonies are the first-line treatment drugs in paediatric wards and amphotericin B injections are the treatment of choice in adults. Severe under-declaration (less than one case in ten notified) was demonstrated thanks to a survey carried out in the paediatric, internal medicine and infectious diseases departments of the five university hospital centres in Algiers, which had an influx of patients from all four corners of the country. Results of both Chapter 5 and Chapter 6 revealed a concordance between human visceral leishmaniasis incidence rates and true prevalence of canine leishmaniasis, providing extra support for the hypothesis that dogs are the main reservoir of the disease. Motivated by the results of the two surveys (Chapters 4 and 5), Chapter 7 describes a literature review of the performance of IFAT when used to estimate the canine leishmaniasis prevalence in the Mediterranean basin. Chapters 8 and 9 present the general discussion and conclusions and recommendations of the overall contribution of this research effort. Even though this work only represent a small addition to knowledge body on visceral leishmaniasis, it allowed us to better describe and understand the epidemiology of visceral leishmaniasis in Algeria and to obtain true prevalence estimates of canine leishmaniasis in various towns in the littoral zone of the country. It showed us the importance of correctly identifying and defining the target population of surveys to obtain the best possible posterior estimates and to optimise control measures. This work also showed the efficacy of the application of appropriate statistical models in a Bayesian framework when confronted with the absence of a gold standard test. Chapter 10 summarizes all references cited in the thesis. [less ▲]

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See detailEuthanasie et don d'organes
DETRY, Olivier ULg

Conference (2016, March 04)

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See detailOlivier Schrauwen e a expansão da banda desenhada belga
Crucifix, Benoît ULg

Conference given outside the academic context (2016)

An internationally translated and critically acclaimed "graphic novelist" superstar, Olivier Schrauwen has often parodied his own posture in strangely inventive comics narrated by his alter ego "O ... [more ▼]

An internationally translated and critically acclaimed "graphic novelist" superstar, Olivier Schrauwen has often parodied his own posture in strangely inventive comics narrated by his alter ego "O. Schrauwen". This presentation offers some insights into the works of Schrauwen, their distinct aesthetics and ironical tone, showing how this style is rooted in a context of alternative comics and self-publishing. Retracing Schrauwen's trajectory from the Flemish to the international comics scene, this presentation will sketch a broad picture of the development and expansion of Belgian comics in the 21st century. Through references to the contemporary work of Brecht Evens, Judith Vanistendael, Brecht Vandenbroucke, as well as the classic comics of Willy Vandersteen, Marc Smeets, Urbanus, Kamagurka and Herr Seele, it proposes a brief introduction to the world of Belgian Dutch-language comics. [less ▲]

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