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See detailStochastic Inventory Routing for Perishable Products
Crama, Yves ULiege; Rezaei Sadrabadi, Mahmood ULiege; Savelsbergh, Martin et al

in Transportation Science (in press)

Different solution methods are developed to solve an inventory routing problem for a perishable product with stochastic demands. The solution methods are compared empirically in terms of average profit ... [more ▼]

Different solution methods are developed to solve an inventory routing problem for a perishable product with stochastic demands. The solution methods are compared empirically in terms of average profit, service level, and actual freshness. The benefits of explicitly considering demand uncertainty are quantified. The computational study highlights that in certain situations a simple ordering policy can already reach a very good performance, but that statistically and economically significant improvements are achieved when using more advanced solution methods. Managerial insights concerning the impact of shelf life and store capacity on profit are also obtained. [less ▲]

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See detailMicrobiological zoonotic emerging risks, transmitted between livestock animals and humans (2007-2015)
Filippitzi, ME; Goumperis, T; Robinson, T et al

in Transboundary and emerging diseases (in press)

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See detailArrêt(s) sur image(s) : usages et pratiques du photogramme
Thonon, Jonathan ULiege

in MethIS : Méthodes et Interdisciplinarité en Sciences Humaines (in press)

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See detailMeat retail conditions within the establishments of Kigali city (Rwanda): bacteriological quality and risk factors for Salmonella occurrence
Niyonzima, Eugene ULiege; Ongol, Martin Patrick; Brostaux, Yves ULiege et al

in Tropical Animal Health and Production (in press)

Meat constitutes one of the major vehicles for human foodborne infections. This study aimed to assess the retail conditions and to determine the microbiological quality and safety of meat retailed within ... [more ▼]

Meat constitutes one of the major vehicles for human foodborne infections. This study aimed to assess the retail conditions and to determine the microbiological quality and safety of meat retailed within the establishments of Kigali (Rwanda). A questionnaire survey was carried out in 150 retail outlets to characterise meat retail conditions. Additionally, 270 retail meat samples were analysed for the enumeration of hygiene indicator bacteria (total mesophilic bacteria and Escherichia coli) and for the qualitative detection of Salmonella, using conventional culture methods. The results revealed that beef was the predominant meat sold within the retail premises of Kigali city, while meat from non-bovine animal species was mainly sold in large establishments. Salmonella was detected in 19.6% of all the retailed meat samples evaluated, whereas the mean loads for total mesophilic bacteria and E. coli were 7.3 and 3.5 log cfu/g, respectively. Three factors, namely the temperature conditions of the meat under retail, the cleanability of the used meat cutting boards, and the training of personnel in hygienic meat handling practices, were found to be significantly (p ≤ 0.05) associated with the risk of Salmonella occurrence in the retailed meat. The findings from this study highlight the need for improvements in hygienic meat handling practices, particularly, in small and medium meat retail establishments in Kigali. [less ▲]

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See detailEffect of flower traits and hosts on the abundance of parasitoids in perennial multiple species wildflower strips sown within oilseed rape (Brassica napus) crops
Hatt, Séverin ULiege; Uyttenbroeck, Roel ULiege; Chevalier Mendes Lopes, Thomas et al

in Arthropod-Plant Interactions (in press)

Reducing the use of insecticides is an important issue for agriculture today. Sowing wildflower strips along field margins or within crops represents a promising tool to support natural enemy populations ... [more ▼]

Reducing the use of insecticides is an important issue for agriculture today. Sowing wildflower strips along field margins or within crops represents a promising tool to support natural enemy populations in agricultural landscapes and, thus, enhance conservation biological control. However, it is important to sow appropriate flower species that attract natural enemies efficiently. The presence of prey and hosts may also guide natural enemies to wildflower strips, potentially preventing them from migrating into adjacent crops. Here, we assessed how seven flower traits, along with the abundance of pollen beetles (Meligethes spp., Coleoptera: Nitidulidae) and true weevils (Ceutorhynchus spp., Coleoptera: Curculionidae), affect the density of parasitoids of these two coleopterans in wildflower strips sown in an oilseed rape field in Gembloux (Belgium). Only flower traits, not host (i.e. pollen beetles and true weevils) abundance, significantly affected the density of parasitoids. Flower colour, ultraviolet reflectance and nectar availability were the main drivers affecting parasitoids. These results demonstrate how parasitoids of oilseed rape pests react to flower cues under field conditions. Similar analyses on the pests and natural enemies of other crops are expected to help to develop perennial flower mixtures able to enhance biological control throughout a rotation system. [less ▲]

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See detailFacultative paedomorphosis as a mechanism promoting intraspecific niche differentiation
Lejeune, Benjamin ULiege; Sturaro, Nicolas ULiege; Lepoint, Gilles ULiege et al

in Oikos (in press)

Organisms with complex life cycles are characterized by a metamorphosis that allows for a major habitat shift and the exploitation of alternative resources. However, metamorphosis can be bypassed in some ... [more ▼]

Organisms with complex life cycles are characterized by a metamorphosis that allows for a major habitat shift and the exploitation of alternative resources. However, metamorphosis can be bypassed in some species through a process called paedomorphosis, resulting in the retention of larval traits at the adult stage and is considered important at both micro- and macroevolutionary scales. In facultatively paedomorphic populations of newts, some individuals retain gills and a fully aquatic life at the adult stage (paedomorphs), while others undergo complete metamorphosis (metamorphs), allowing for a terrestrial life-stage. Because facultative paedomorphosis affects trophic structures and feeding mechanism of newts, one hypothesis is that it may be maintained as a trophic polymorphism, with the advantage to lessen intraspecific competition during the shared aquatic life-stage. Here, we tested this hypothesis combining stomach content data with stable isotope techniques, using carbon and nitrogen stable isotopes, in facultatively paedomorphic alpine newts Ichthyosaura alpestris. Both stomach content and stable isotope analyses showed that paedomorphs had smaller trophic niches and were more reliant on pelagic resources, while metamorphs relied more on littoral resources, corresponding to a polyphenism along the littoral-pelagic axis and the extension of the population's trophic niche to otherwise ‘underused’ pelagic resources by paedomorphs. Interestingly, stable isotopes revealed that the trophic polyphenism was less marked in males than in females and potentially linked to sexual activity. Although paedomorphosis and metamorphosis are primarily seen as results of tradeoffs between the advantages of using aquatic versus terrestrial habitats, this study provides evidence that additional forces, such as intraspecific trophic niche differences between morphs and trophic niche expansion, may play an important role in the persistence of this dimorphism in heterogeneous environments. Moreover, the different patterns found in males and females show the importance of considering sex to understand the evolutionary ecology of trophic polymorphisms. [less ▲]

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See detailCarte géologique de Wallonie à l'échelle 1:25 000. Notice explicative. Hamoir-Ferrières n°49/1-2
Marion, Jean-Marc ULiege; Barchy, Laurent

Book published by SPW/DGARNE - Révision (in press)

New geological map of Wallonia published at the scale of 1/25 000, based on a new field work and using previous scientific data produced since the previous editions of Lohest and Fourmarier (1900)

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See detailDroit constitutionnel belge (année académique 2017-2018) - Principes de droit constitutionnel belge
Behrendt, Christian ULiege

Book published by Serice de droit public et constitutionnel de l'Université de Liège (in press)

Syllabus pour le cours de Droit constitutionnel (DROI1203-4) en baccalauréat en droit de l'Université de Liège, Faculté de Droit.

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See detailIntensity and memory characteristics of near-death experiences
Martial, Charlotte ULiege; Charland-Verville, Vanessa ULiege; Cassol, Helena ULiege et al

in Consciousness & Cognition (in press)

Memories of Near-Death Experiences (NDEs) seem to be very detailed and stable over time. At present, there is still no satisfactory explanation for the NDEs’ rich phenomenology. Here we compared ... [more ▼]

Memories of Near-Death Experiences (NDEs) seem to be very detailed and stable over time. At present, there is still no satisfactory explanation for the NDEs’ rich phenomenology. Here we compared phenomenological characteristics of NDE memories with the reported experience’s intensity. We included 152 individuals with a self-reported “classical” NDE (i.e. occurring in life-threatening conditions). All participants completed a mailed questionnaire that included a measure of phenomenological characteristics of memories (the Memory Characteristics Questionnaire; MCQ) and a measure of NDE’s intensity (the Greyson NDE scale). Greyson NDE scale total score was positively correlated with MCQ total score, suggesting that participants who described more intense NDEs also reported more phenomenological memory characteristics of NDE. Using MCQ items, our study also showed that NDE’s intensity is associated in particular with sensory details, personal importance and reactivation frequency variables. [less ▲]

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See detailImmersion et réflexivité. L’avatar au cœur de la construction de la posture vidéoludique
Delbouille, Julie ULiege; Barnabé, Fanny ULiege; Dozo, Björn-Olav ULiege

in Audet, René; Xanthos, Nicolas (Eds.) Le personnage contemporain (in press)

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See detailFirst results in the use of milk mid-infrared spectra in the detection of lameness in Austrian dairy cows
Mineur, Axelle ULiege; Köck, Astrid; Grelet, Clément ULiege et al

in Agriculturae Conspectus Scientificus (in press)

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See detailFully leafed induced subtrees
Blondin Massé, Alexandre; de Carufel, Julien; Goupil, Alain et al

E-print/Working paper (in press)

Let G be a simple graph of n vertices. We consider the problem ISil of deciding whether there exists an induced subtree with exactly i ≤ n vertices and l leaves in G. We also study the associated ... [more ▼]

Let G be a simple graph of n vertices. We consider the problem ISil of deciding whether there exists an induced subtree with exactly i ≤ n vertices and l leaves in G. We also study the associated optimization problem, that consists in computing the maximal number of leaves, denoted by L_G(i), realized by an induced subtree with i vertices, for 2 ≤ i ≤ n. We compute the values of the map L_G for some classical families of graphs and in particular for the d-dimensional hypercubic graphs Q_d , d ≤ 6. Then we prove that the ISil problem is in general NP-complete. We also describe a nontrivial branch and bound algorithm that computes the function L_G for any simple graph G. In the special case where G is a tree, we provide a O(δn^3) time and O(n^2) space algorithm, where δ is the maximum degree of G. Finally, we exhibit a bijection between the set of discrete derivative of the sequences L_G (i) where G is caterpillar, and the set of prefix normal words. [less ▲]

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See detailPermutations and negative beta-shifts
Charlier, Emilie ULiege; Steiner, Wolfgang

in International Journal of Foundations of Computer Science (in press)

Elizalde (2011) characterized which permutations can be obtained by ordering consecutive elements in the trajectories of (positive) beta-transformations and beta-shifts. We prove similar results for ... [more ▼]

Elizalde (2011) characterized which permutations can be obtained by ordering consecutive elements in the trajectories of (positive) beta-transformations and beta-shifts. We prove similar results for negative bases beta. [less ▲]

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See detailCyclic and Fatigue Behaviour of Rock Materials: Review, Interpretation and Research Perspectives
Cerfontaine, Benjamin ULiege; Collin, Frédéric ULiege

in Rock Mechanics & Rock Engineering (in press)

The purpose of this paper is to provide a comprehensive state of the art of fatigue and cyclic loading of natural rock materials. Papers published in the literature are classified and listed in order to ... [more ▼]

The purpose of this paper is to provide a comprehensive state of the art of fatigue and cyclic loading of natural rock materials. Papers published in the literature are classified and listed in order to ease bibliographical review, to gather data (sometimes contradictory) on classical experimental results and to analyse the main interpretation concepts. Their advantages and limitations are discussed, and perspectives for further work are highlighted. The first section summarises and defines the different experimental set-ups (type of loading, type of experiment) already applied to cyclic/fatigue investigation of rock materials. The papers are then listed based on these different definitions. Typical results are highlighted in next section. Fatigue/cyclic loading mainly results in accumulation of plastic deformation and/or damage cycle after cycle. A sample cyclically loaded at constant amplitude finally leads to failure even if the peak load is lower than its monotonic strength. This subcritical crack is due to a diffuse microfracturing and decohesion of the rock structure. The third section reviews and comments the concepts used to interpret the results. The fatigue limit and S–N curves are the most common concepts used to describe fatigue experiments. Results published from all papers are gathered into a single figure to highlight the tendency. Predicting the monotonic peak strength of a sample is found to be critical in order to compute accurate S–N curves. Finally, open questions are listed to provide a state of the art of grey areas in the understanding of fatigue mechanisms and challenges for the future. [less ▲]

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See detailMorphological integration and alternative life history strategies: a case study in a facultatively paedomorphic newt
Tomašević, Natasa; Cvijanović, Milena; Denoël, Mathieu ULiege et al

in Journal of Experimental Zoology. Part B, Molecular and Developmental Evolution (in press)

Tetrapod limbs are serially homologous structures that represent a particularly interesting model for studies on morphological integration, i.e. the tendency of developmental systems to produce correlated ... [more ▼]

Tetrapod limbs are serially homologous structures that represent a particularly interesting model for studies on morphological integration, i.e. the tendency of developmental systems to produce correlated variation. In newts, limbs develop at an early larval stage and grow continuously, including after the habitat transition from water to land following metamorphosis. However, aquatic and terrestrial environments impose different constraints and locomotor modes that could affect patterns of morphological integration and evolvability. We hypothesize that this would be the case for alternative heterochronic morphs in newts, i.e. aquatic paedomorphs that keep gills at the adult stage and adult metamorphs that are able to disperse on land. To this end, we analysed patterns and strengths of correlations between homologous skeletal elements of the fore- and hindlimbs as well as among skeletal elements within limbs in both phenotypes in the alpine newt, Ichthyosaura alpestris. Our results showed that metamorphs and paedomorphs had similar, general patterns of limb integration. Partial correlations between homologous limb elements and within limb elements were higher in paedomorphs when compared to metamorphs. Decrease in partial correlation between homologous limb elements in metamorphs is accompanied with a higher evolvability of the terrestrial morph. All these results indicate that environmental demands shaped the patterns of morphological integration of alpine newt limbs and that the observed diversity in correlation structure could be related to a qualitative difference in the modes of locomotion between the morphs. [less ▲]

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See detailDesign and Management of Freight Transport Networks: Intermodal Transport and Externalities
Mostert, Martine ULiege

in 4OR : Quarterly Journal of the Belgian, French and Italian Operations Research Societies (in press)

Ph.D. thesis summary. Please refer to http://orbi.ulg.ac.be/handle/2268/211640 for the complete thesis.

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See detailQuatre configurations pour créer une dynamique interactive entre formation et recherche Expériences dans le domaine de la formation des professionnels de la santé
Faulx, Daniel ULiege; Burlet, Géraldine ULiege; Bernard, Nicolas ULiege et al

in Recherches Qualitatives (in press)

Dans cette contribution, nous nous penchons sur la possibilité de créer une dynamique interactive entre intervention sur le terrain et recherche scientifique dans le domaine de la formation. Les terrains ... [more ▼]

Dans cette contribution, nous nous penchons sur la possibilité de créer une dynamique interactive entre intervention sur le terrain et recherche scientifique dans le domaine de la formation. Les terrains d’application se situent tous ici dans le domaine de la santé. Nous présentons quatre configurations d’une telle complémentarité. Chacune d’entre elles représente une articulation différente entre le but de développement des participants et celui de production de savoirs scientifiques. Dans le premier cas, une démarche de recherche est entreprise en amont de la conception d’une formation. La deuxième configuration illustre une recherche scientifique appliquée à un dispositif d’intervention existant et qui vient en retour en modifier la logique. Pour la troisième, il s’agit d’une articulation continue entre recherche et formation s’alimentant mutuellement dans une logique de recherche-action. Enfin, la quatrième partie se penche sur trois dispositifs pédagogiques dont la caractéristique est de combiner des intentions formatives avec des préoccupations de recherche [less ▲]

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See detailLa place de l'arbre dans les systèmes agricoles par les populations locales
Hick, Aurélie ULiege; Hallin, Maud; Tshibungu, Alain et al

in Mahy, Grégory; Colinet, Gilles; Bogaert, Jan (Eds.) Anthropisation au Katanga (in press)

Dans un contexte de déforestation massive dans les zones rurales adjacentes aux grandes métropoles de la République Démocratique du Congo (RDC), zones d’approvisionnement en bois-énergie, l’identification ... [more ▼]

Dans un contexte de déforestation massive dans les zones rurales adjacentes aux grandes métropoles de la République Démocratique du Congo (RDC), zones d’approvisionnement en bois-énergie, l’identification de la place et du rôle que prend l’arbre dans les villages constituent un préalable à tous plan de restauration forestière. Ce chapitre porte sur les connaissances taxonomiques, les usages et la distribution des espèces arborées indigènes au sein de quatre villages en zone rurale adjacente à la ville de Lubumbashi, chef-lieu de la province du Katanga en RDC. Un total de 49 espèces indigènes de la forêt claire a été identifié par les 51 familles interrogées. Les utilisations sont classées en 6 catégories. Neuf espèces sont connues par plus de 50% des familles et correspondent aux espèces les plus utilisées pour l’alimentation via la consommation de leurs fruits et pour la confection d’outils. Les espèces citées par les personnes interrogées ne sont pas présentes dans le système agricole. La densité d’arbre à l’hectare au sein des champs est faible. Les espèces présentes sont des espèces résistantes aux facteurs de dégradation. Cette étude a montré que la connaissance taxonomique est limitée aux espèces les plus utilisées. Il n’y a pas de gestion intégrée de l’arbre au sein du système agricole dans la zone rurale adjacente à la ville de Lubumbashi. [less ▲]

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See detailThe effect of spaceflight and microgravity on the human brain
Van Ombergen, Angelique; Demertzi, Athina ULiege; Tomilovskaya et al

in Journal of Neurology (in press)

Microgravity, confinement, isolation, and immobilization are just some of the features astronauts have to cope with during space missions. Consequently, long-duration space travel can have detrimental ... [more ▼]

Microgravity, confinement, isolation, and immobilization are just some of the features astronauts have to cope with during space missions. Consequently, long-duration space travel can have detrimental effects on human physiology. Although research has focused on the cardiovascular and musculoskeletal system in particular, the exact impact of spaceflight on the human central nervous system remains to be determined. Previous studies have reported psychological problems, cephalic fluid shifts, neurovestibular problems, and cognitive alterations, but there is paucity in the knowledge of the underlying neural substrates. Previous space analogue studies and preliminary spaceflight studies have shown an involvement of the cerebellum, cortical sensorimotor, and somatosensory areas and the vestibular pathways. Extending this knowledge is crucial, especially in view of long-duration interplanetary missions (e.g., Mars missions) and space tourism. In addition, the acquired insight could be relevant for vestibular patients, patients with neurodegenerative disorders, as well as the elderly population, coping with multisensory deficit syndromes, immobilization, and inactivity. [less ▲]

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