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See detailInsect pathogenic Aspergillus species in mosquito (Diptera: Culicidae) control compared to Metarhizium anisopliae
Bawin, Thomas ULg

Doctoral thesis (2016)

Many mosquito (Diptera: Culicidae) species are vectors responsible for the transmission of infectious diseases of medical and veterinary importance. Risk for infection considerably increased during the ... [more ▼]

Many mosquito (Diptera: Culicidae) species are vectors responsible for the transmission of infectious diseases of medical and veterinary importance. Risk for infection considerably increased during the last decades due to climate changes and increasing global trade. Vector control is essential for public health management. Integrated pest management is now promoted due to harmful side effects of the chemical insecticides classically used for mosquito control and insect resistance development. This PhD thesis takes part in the selection process of insect pathogenic fungi. Three biological models (Aspergillus clavatus Desmazieres, Aspergillus flavus Link, and Metarhizium anisopliae (Metschnikoff) Sorokin) were selected and investigated regarding their spore insecticidal activity, mode of action, and selectivity. Throughout this scheme, the use of agricultural materials and derivatives in fermentation processes was emphasized. Production methods and insecticidal potential of the fungi were first investigated. On the one hand, the two Aspergillus species were compared to M. anisopliae regarding their spore production when cultured on agro-industrial substrates (white rice and wheat bran) and their insecticidal effect on larvae of the southern house mosquito, Culex quinquefasciatus Say. Our results showed that both substrates are suitable to culture the three insect pathogenic fungal species; but wheat bran-based media increased from 3 to 7-fold the spore yields in solid-state compared to white rice-based media. Also, insect pathogenic Aspergillus species were suggested to yield in similar spore levels in such conditions (in a range of 10^9 spores per g of substrate) and be as virulent against mosquito larvae compared to M. anisopliae. On the other hand, a bioreactor design intended to support large-scale production on agricultural materials by combining the technological advantages of submerged and solid-state fermentations was implemented using A. clavatus. This system allowed facility in recuperation and purification of spores (confined on a packed solid substrate) that retained virulence against mosquito larvae; but also metabolites (contained in a circulating liquid medium) that showed insecticidal effect. The mechanisms responsible for the insecticidal effects of the spores, and their selectivity were then investigated. On the one hand, the invasion routes of A. clavatus spores on mosquito larvae were investigated by light and electron microscopy. Histological observations suggest that toxins secreted by active germinating spores of A. clavatus in the digestive tract altered the larval tissues, leading to necrosis and causing larval death. Fungal proliferation and sporulation then occurred during a saprophytic phase. Such action mode also probably occurred in the case of the two other species. On the other hand, the insecticidal activity of the fungi was assessed against the pea aphid, Acyrthosiphon pisum Linnaeus. Adult A. pisum aphids were susceptible (increased mortality and decreased reproductive potential) to the three fungal species. As a consequence, these fungi would probably be able to infect a broad spectrum of insect hosts (whatever terrestrial or aquatic) once released in the environment. The implications of the results for mosquito control and application strategies are finally discussed, and perspectives for future works proposed. [less ▲]

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See detailDix ans de ``Maths à Modeler à Liège'' ou comment un enseignant/chercheur s'invite dans des classes du secondaire
Rigo, Michel ULg

Conference given outside the academic context (2016)

Les missions d'un professeur d'université sont multiples : recherche, enseignement mais aussi citoyenneté. Depuis une dizaine d'années, je réalise de multiples activités de sensibilisation aux ... [more ▼]

Les missions d'un professeur d'université sont multiples : recherche, enseignement mais aussi citoyenneté. Depuis une dizaine d'années, je réalise de multiples activités de sensibilisation aux mathématiques : exposés, activités ludiques en petits groupes, etc. En répondant modestement à la question : "les maths ça sert à quoi ?", le but recherché est de démontrer l'utilité souvent méconnue des mathématiques, et de la recherche dans ce domaine (Google, réseaux sociaux, jeux vidéos, magie, etc.). Dans cette présentation, je dresserai tout d'abord l'historique du projet et tenterai d'analyser les actions menées. Ensuite, l'auditoire assistera à un tour de mathémagie et participera, de façon interactive, à un jeu démontrant l'importance du concept de preuve en mathématique. Ces jeux sont tirés de "Situations-Recherche pour la classe" développées par des chercheurs grenoblois. Enfin, j'expliquerai comment des étudiants de l'ULg (bacheliers, masters, étudiants à l'agrégation) et des doctorants participent à cette action. [less ▲]

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See detailAnatomie chirurgicale du plancher Pelvien et du rétropéritoine chez la femme
Bonnet, Pierre ULg

Conference (2016, June 22)

Leçon introductive reprenant les notions anatomiques essentielles à maîtriser lors de l'approche chirurgicale du pelvis et du rétropéritoine chez la femme. Approche constructive par la réalisation ... [more ▼]

Leçon introductive reprenant les notions anatomiques essentielles à maîtriser lors de l'approche chirurgicale du pelvis et du rétropéritoine chez la femme. Approche constructive par la réalisation extemporanée de schémas projetés. [less ▲]

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See detailDesign criteria and experimental performance - Extended end-plate
Demonceau, Jean-François ULg

Conference (2016, June 21)

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See detailForest Inventory with Terrestrial LiDAR: A Comparison of Static and Hand-Held Mobile Laser Scanning
Bauwens, Sébastien ULg; Bartholomeus, Harm; Calders, Kim et al

in Forests (2016), 7(6), 127

The application of static terrestrial laser scanning (TLS) in forest inventories is becoming more effective. Nevertheless, the occlusion effect is still limiting the processing efficiency to extract ... [more ▼]

The application of static terrestrial laser scanning (TLS) in forest inventories is becoming more effective. Nevertheless, the occlusion effect is still limiting the processing efficiency to extract forest attributes. The use of a mobile laser scanner (MLS) would reduce this occlusion. In this study, we assessed and compared a hand-held mobile laser scanner (HMLS) with two TLS approaches (single scan: SS, and multi scan: MS) for the estimation of several forest parameters in a wide range of forest types and structures. We found that SS is competitive to extract the ground surface of forest plots, while MS gives the best result to describe the upper part of the canopy. The whole cross-section at 1.3 m height is scanned for 91% of the trees (DBH > 10 cm) with the HMLS leading to the best results for DBH estimates (bias of 0.08 cm and RMSE of 1.11 cm), compared to no fully-scanned trees for SS and 42% fully-scanned trees for MS. Irregularities, such as bark roughness and non-circular cross-section may explain the negative bias encountered for all of the scanning approaches. The success of using MLS in forests will allow for 3D structure acquisition on a larger scale and in a time-efficient manner. [less ▲]

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See detailGreenland Ice Sheet seasonal and spatial mass variability from model simulations and GRACE (2003–2012)
Alexander, P.; Tedesco, M.; Schlegel, N-J et al

in Cryosphere (The) (2016), 10

Improving the ability of regional climate models (RCMs) and ice sheet models (ISMs) to simulate spatiotemporal variations in the mass of the Greenland Ice Sheet (GrIS) is crucial for prediction of future ... [more ▼]

Improving the ability of regional climate models (RCMs) and ice sheet models (ISMs) to simulate spatiotemporal variations in the mass of the Greenland Ice Sheet (GrIS) is crucial for prediction of future sea level rise. While several studies have examined recent trends in GrIS mass loss, studies focusing on mass variations at sub-annual and sub-basin-wide scales are still lacking. At these scales, processes responsible for mass change are less well understood and modeled, and could potentially play an important role in future GrIS mass change. Here, we examine spatiotemporal variations in mass over the GrIS derived from the Gravity Recovery and Climate Experiment (GRACE) satellites for the January 2003–December 2012 period using a "mascon" approach, with a nominal spatial resolution of 100 km, and a temporal resolution of 10 days. We compare GRACE-estimated mass variations against those simulated by the Modèle Atmosphérique Régionale (MAR) RCM and the Ice Sheet System Model (ISSM). In order to properly compare spatial and temporal variations in GrIS mass from GRACE with model outputs, we find it necessary to spatially and temporally filter model results to reproduce leakage of mass inherent in the GRACE solution. Both modeled and satellite-derived results point to a decline (of −178.9 ± 4.4 and −239.4 ± 7.7 Gt yr−1 respectively) in GrIS mass over the period examined, but the models appear to underestimate the rate of mass loss, especially in areas below 2000 m in elevation, where the majority of recent GrIS mass loss is occurring. On an ice-sheet-wide scale, the timing of the modeled seasonal cycle of cumulative mass (driven by summer mass loss) agrees with the GRACE-derived seasonal cycle, within limits of uncertainty from the GRACE solution. However, on sub-ice-sheet-wide scales, some areas exhibit significant differences in the timing of peaks in the annual cycle of mass change. At these scales, model biases, or processes not accounted for by models related to ice dynamics or hydrology, may lead to the observed differences. This highlights the need for further evaluation of modeled processes at regional and seasonal scales, and further study of ice sheet processes not accounted for, such as the role of subglacial hydrology in variations in glacial flow. [less ▲]

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See detailMolecular Alterations and Everolimus Efficacy in Human Epidermal Growth Factor Receptor 2-Overexpressing Metastatic Breast Cancers: Combined Exploratory Biomarker Analysis From BOLERO-1 and BOLERO-3.
Andre, Fabrice; Hurvitz, Sara; Fasolo, Angelica et al

in Journal of clinical oncology : official journal of the American Society of Clinical Oncology (2016), 34(18), 2115-24

PURPOSE: Two recent phase III trials, BOLERO-1 and BOLERO-3 (Breast Cancer Trials of Oral Everolimus), evaluated the addition of everolimus to trastuzumab and chemotherapy in human epidermal growth factor ... [more ▼]

PURPOSE: Two recent phase III trials, BOLERO-1 and BOLERO-3 (Breast Cancer Trials of Oral Everolimus), evaluated the addition of everolimus to trastuzumab and chemotherapy in human epidermal growth factor receptor 2-overexpressing advanced breast cancer. The current analysis aimed to identify biomarkers to predict the clinical efficacy of everolimus treatment. METHODS: Archival tumor samples from patients in BOLERO-1 and BOLERO-3 were analyzed using next-generation sequencing, immunohistochemistry, and Sanger sequencing. RESULTS: Biomarker data were available for 549 patients. PIK3CA activating mutations and PTEN loss were reported in 30% and 16% of BOLERO-1 samples and in 32% and 12% of BOLERO-3 samples, respectively. PI3K pathway was hyperactive (PIK3CA mutations and/or PTEN loss and/or AKT1 mutation) in 47% of BOLERO-1 and 41% of BOLERO-3 samples. In both studies, differential progression-free survival (PFS) benefits of everolimus were consistently observed in patient subgroups defined by their PI3K pathway status. When analyzing combined data sets of both studies, everolimus was associated with a decreased hazard of progression in patients with PIK3CA mutations (hazard ratio [HR], 0.67; 95% CI, 0.45 to 1.00), PTEN loss (HR, 0.54; 95% CI, 0.31 to 0.96), or hyperactive PI3K pathway (HR, 0.67; 95% CI, 0.48 to 0.93). Patients with wild-type PIK3CA (HR, 1.10; 95% CI, 0.83 to 1.46), normal PTEN (HR, 1.00; 95% CI, 0.80 to 1.26), or normal PI3K pathway activity (HR, 1.19; 95% CI, 0.87 to 1.62) did not derive PFS benefit from everolimus. CONCLUSION: This analysis, although exploratory, suggests that patients with human epidermal growth factor receptor 2-positive advanced breast cancer having tumors with PIK3CA mutations, PTEN loss, or hyperactive PI3K pathway could derive PFS benefit from everolimus. [less ▲]

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See detailORCmKit: an open-source library for organic Rankine cycle modelling and analysis
Dickes, Rémi ULg; Ziviani, Davide; van den Broek, Martjin et al

in Proceedings of ECOS 2016 (2016, June 20)

As for many other technologies, modelling and simulation of organic Rankine cycles (ORCs) are crucial for design, optimization and control purposes. However, model development is often time consuming and ... [more ▼]

As for many other technologies, modelling and simulation of organic Rankine cycles (ORCs) are crucial for design, optimization and control purposes. However, model development is often time consuming and the scientific community lacks of open-access tools to study ORC systems. For these reasons, researchers from the universities of Liège and Ghent in Belgium gathered their knowledge and created “ORC modelling Kit” (ORCmKit), an open-source library dedicated to the steady-state simulation and analysis of organic Rankine cycles. Both component-level and cycle-level models are provided and different ORC architectures can be simulated. For each of the main component of ORC systems, different models are available with increasing complexity which allows a wide range of modelling possibilities. In order to remain general and accessible to as many people as possible, three widely used programming languages are covered within ORCmKit, i.e. Matlab, Python and EES (Engineering Equation Solver). Besides source codes, ORCmKit also includes calibration tools for empirical and semi-empirical models as well as a complete documentation for ease of use. [less ▲]

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See detailStorytelling in Videogames: From “Narrative” Towards “Fictional Universe”
Barnabé, Fanny ULg

Conference (2016, June 18)

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See detailEvaluation of Adaptive Facades: The Case Study of AGC Headquarter in Belgium
Attia, Shady ULg; Bashandy, Hamza

in Belis, Jan; Louter, Christian (Eds.) Challenging Glass 5 (2016, June 17)

The evaluation of adaptive facades presents a challenge because there is no established evaluation strategy to systematically reach this goal and many of the available façade performance evaluation tools ... [more ▼]

The evaluation of adaptive facades presents a challenge because there is no established evaluation strategy to systematically reach this goal and many of the available façade performance evaluation tools have limited applicability for such advanced building facades. This paper presents a case study for an adaptive glass façade and evaluates its performance. The evaluation focuses mainly on pre and post construction phase of adaptive facades: The design assist phase (including the durability test, visual mockup, onsite panel mounting and weather stripping), the commissioning phase (field verification and performance testing) and the monitoring phase. The selected project is a nearly zero energy building with unique façade comprising thermal isolated glass sunshades printed with white silk screen. These louvers respond dynamically and automatically to the angle of the sun which improves the control over energy consumption, solar radiation and glare with the ability to admit natural light into the building. The paper is part of the research activities of working group 3 of the European COST Action 1403 on “Adaptive Facades “. Different methods were used for evaluation, this include: interviews with the architect, façade engineer and technical control specialist, reviews of standard and codes and a systematic process mapping. A documentation of the case study describing the post construction occupant comfort and façade operation was prepared. This paper’s audience is mainly architects, building façade engineers together with facility managers concerned with the process of design, construction and operation of adaptive glass facades. The outcome of this study identifies effective strategies for the design and performance evaluation of optimal adaptive facades. [less ▲]

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See detailETUDE DE LA DYNAMIQUE DE LA DESERTIFICATION DANS LE BASSIN VERSANT DE LA MOULOUYA EN INTEGRANT LES DONNEES ISSUES DE LA TELEDETECTION ET LES DONNEES SOCIO-ECONOMIQUES
Mokhtari, Noureddine ULg

Doctoral thesis (2016)

La recherche sur la désertification et la dégradation de l’environnement est très complexe et vise la mise en relation entre les ressources de l’environnement, leurs limites de durabilité et des usages ... [more ▼]

La recherche sur la désertification et la dégradation de l’environnement est très complexe et vise la mise en relation entre les ressources de l’environnement, leurs limites de durabilité et des usages qui se font de ces ressources par l’homme en tant qu’agent économique qui vise à améliorer son bien-être. Dans le bassin versant de la Moulouya caractérisé par un climat essentiellement aride à semi-aride, une augmentation sensible de la population et une forte hausse de la demande en ressources naturelles, le problème de la désertification se pose en termes d’adaptation des besoins de la population aux contraintes du milieu en vue de maintenir la durabilité des ressources. Dans ce sens, le challenge consiste en un double objectif, premièrement l’évaluation de la désertification à travers l’analyse de l’état de dégradation du milieu et deuxièmement, l’étude des causes de cette dégradation moyennant des enquêtes axées sur les pratiques agricoles et la formulation de propositions d’actions à entreprendre pouvant être utilisés de manière opérationnelle par les acteurs locaux et les pouvoirs publics. Ainsi, le suivi de la dynamique des phénomènes biophysiques liés à la désertification s’est fait essentiellement à travers l’étude de l’évolution du climat et de la qualité de la végétation à l’échelle de l’ensemble de la zone étudiée (NDVI) et au niveau d’une zone d’intérêt pour la recherche (occupation du sol). Pour la végétation, le suivi spatio-temporel de la végétation a montré pour les trois sources de données à basse résolution utilisées (GIMMS, MEDOKADS et SPOT) des évolutions similaires de l’indice de végétation NDVI. Malgré les différences entre les amplitudes de variation du NDVI, liées essentiellement aux spécificités des algorithmes de traitement, les trois séries données conservent la même tendance stationnaire au cours du temps. D’une manière générale, les fluctuations du NDVI mises en évidence à l’aide des données NDVI à basse résolution reflètent principalement les variations spatio-temporelles en quantité et en qualité des précipitations d’une année par rapport à une autre et ne montrent aucune tendance particulière concernant la qualité de la végétation. L’identification des zones sensibles à la désertification, réalisée sur la base de l’approche MEDALUS, a montré que les zones fragiles et critiques totalisent 61% de la superficie du bassin versant, soit une superficie d’environ 3,25 millions d’Ha. Spatialement, les zones sensibles à la dégradation se trouvent aussi bien dans la Basse Moulouya que dans les Hauts Plateaux et la vallée de Missour constitués essentiellement de parcours steppiques. L’analyse de la dynamique d’occupation du sol à travers l’utilisation des images satellites (LANDSAT) pour la commune de Tissaf, choisie comme zone d’intérêt pour la recherche, a révélé une dégradation qualitative de la végétation. En effet, de grandes superficies d’Alfa dense à très dense (végétation climacique) se sont dégradées pour se retrouver dans la classe d’Alfa faiblement dense, soit une diminution de l’ordre de 16.199 Ha sur 20 ans. L’analyse des causes de la dégradation des parcours au niveau de la commune de Tissaf à travers l’étude de la productivité des parcours et du système d’élevage pastoral a révélé que le capital, en tant que facteur de production, joue un rôle important dans les stratégies d’utilisation des ressources fourragères « gratuites » issues des parcours collectifs. Ainsi, les grands éleveurs sédentaires ou semi-nomades disposant d’importants fonds propres et grâce à une utilisation plus opportuniste des parcours collectifs paraissent profiter davantage de ces ressources (46.478,15 UF) par rapport aux petits éleveurs sédentaires et transhumants (5.148,70 UF et 18.714,40 UF). Les petits éleveurs qui adaptent l’effectif de leur cheptel en fonction des conditions du milieu (décapitalisation en période de sécheresse) semblent profiter moins en quantité et en qualité des ressources pastorales disponibles. En guise de conclusion, la thèse propose des scénarios d’adaptation des systèmes de production agricoles qui peuvent être utilisés d’une manière opérationnelle par les acteurs locaux et les pouvoirs publics en vue d’orienter les stratégies de développement et d’investissement vers les secteurs rentables économiquement et qui respectent en même temps l’environnement. [less ▲]

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See detailL'exercice des tâches régaliennes en Belgique : sommes-nous un Etat structurellement vulnérable ?
Behrendt, Christian ULg

Conference given outside the academic context (2016)

Conférence donnée à Wavre, Hôtel de ville, 17 juin 2016, lors d'une réunion conjointe de mandataires du Brabant wallon et de Flandre occidentale

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See detailMonitoring partnership networks- A graph theory approach
Faraz, Alireza ULg; Treiblmaier, Horst; Gerschberger, Markus

Conference (2016, June 17)

Recently, companies are forming strong relationships with their strategic suppliers and customers in order to maximize their profit in the global market. Such a partnership or strategic alliance is based ... [more ▼]

Recently, companies are forming strong relationships with their strategic suppliers and customers in order to maximize their profit in the global market. Such a partnership or strategic alliance is based on the mutual needs of both parties. A partnership network is formed by different strategic firms (e.g., suppliers, manufacturers, distributors, retailers) who intend to establish strong relationships together but without losing their ownership, power and control on the firm. For example, if supplier X has a strong relationship with customer Y and Y has a strong relationship with supplier Z, then X, Y and Z can form a partnership network with three nodes (X, Y and Z) and two edges (X ->Y and Z->Y). In this paper, we develop a statistical methods to study the normal behaviour of partnership networks. We furthermore develop a methodology that will help diagnose the nature of identified unusual network behavior. [less ▲]

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See detailDévelopper du code avec une équipe de "non-geeks" à l'ULg
Boman, Romain ULg

Speech/Talk (2016)

Cette présentation a été faite aux "Geeks Anonymes" de l'Université de Liège le 17 juin 2016. J'y présente les techniques de développement de logiciels vers lesquelles notre groupe de recherche a convergé ... [more ▼]

Cette présentation a été faite aux "Geeks Anonymes" de l'Université de Liège le 17 juin 2016. J'y présente les techniques de développement de logiciels vers lesquelles notre groupe de recherche a convergé après 20 ans de pratique. En particulier, je détaille les compromis qui ont dû être trouvés pour aider les thésards et ingénieurs de recherche peu à l'aise avec l'informatique. [less ▲]

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See detailEstetrol Attenuates Neonatal Hypoxic-Ischemic Encephalopathy: Preclinical Studies
Tskitishvili, Ekaterine ULg; Nisolle, Michelle ULg; Noël, Agnès ULg et al

Poster (2016, June 17)

Brain hypoxia and ischemia due to systemic hypoxemia and reduced cerebral blood flow (CBF) are the primary causes of neonatal hypoxic-ischemic encephalopathy (HIE) accompanied by gray and white matter ... [more ▼]

Brain hypoxia and ischemia due to systemic hypoxemia and reduced cerebral blood flow (CBF) are the primary causes of neonatal hypoxic-ischemic encephalopathy (HIE) accompanied by gray and white matter injuries occurring in neonates. Perinatal HIE still remains a challenge in perinatal medicine. About 20% of affected newborns die in the postnatal period, and an additional 25% will sustain childhood disabilities. So far no medical treatment provides important neuroprotection against HIE. Studies of new neuroprotective agents in animal models of HIE may have importance for the development of new compounds and treatment strategies for this pathological condition. Estetrol (E4) is a recently described estrogen with four hydroxyl-groups that is synthesized exclusively during pregnancy by the human fetal liver. It has important antioxidative activity. To study the neuroprotective and therapeutic effects of E4 in vivo neonatal HIE model of 7-day-old newborn rat pups was used. Rat pups body temperatures were examined along with their body and brain weights. Brains were studied at the level of the hippocampus and cortex. Intact cell counting and expressions of markers for neuronal cell viability (microtubule-associated protein-2 (MAP-2)), neurogenesis (doublecortin (DCX)) and angiogenesis (vascular-endothelial growth factor (VEGF)) were evaluated by histo- and immunohistochemistry. The serum levels of brain damage markers (S100B and glial fibrillary acidic protein (GFAP)) were measured by ELISA. Our results demonstrate for the first time that E4 has a significant neuroprotective and therapeutic effects. It decreases the early gray matter loss and promotes neuro- and angiogenesis in vivo. Estetrol treatment has no effects on body weight, brain weight or body temperature. Taken together, E4 might become an important safe and physiological substance to treat neonatal HIE. [less ▲]

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See detailLa gestion des ressources avec Alma à l'Université de Liège
Richelle, Laurence ULg

Conference given outside the academic context (2016)

Retour d'expérience client sur la gestion des ressources imprimées et électroniques avec le système de gestion de bibliothèque Alma depuis février 2015.

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See detailHépatocarcinome: Place de la chirurgie
DETRY, Olivier ULg

Conference given outside the academic context (2016)

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