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See detailGouvy Jazz & Blues Festival Août 2015
Sacré, Robert ULg

E-print/Working paper (2015)

Compte rendu du festival BLUES avec photos

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See detailLe Parc National Sahamalaza - Iles Radama serait-il l’ultime refuge pour certaines espèces de lémuriens du nord-ouest de Madagascar ?
Wilmet, Leslie ULg; Beudels-Jamar, Roseline C.; Schwitzer, Christoph et al

in Tropicultura (2015)

Depuis des millions d’années, la faune et la flore terrestre de Madagascar ont évolué dans un espace isolé. Suite à cette situation, le niveau d’endémisme y est très élevé et l’ensemble de l’île ... [more ▼]

Depuis des millions d’années, la faune et la flore terrestre de Madagascar ont évolué dans un espace isolé. Suite à cette situation, le niveau d’endémisme y est très élevé et l’ensemble de l’île représente un des plus importants hotspot de biodiversité. Madagascar fait aussi partie des pays les plus touchés en termes de destruction des habitats naturels ; 90 % de la végétation d’origine est aujourd’hui perdue. La déforestation et la fragmentation des habitats forestiers menace particulièrement les primates de l’île, les lémuriens. L’île est considérée par de nombreuses organisations internationales comme une priorité pour la conservation de la nature, autant dans le domaine zoologique que botanique. Les premières aires protégées de Madagascar ont été établies en 1927 et l’île en compte aujourd’hui 47. Cet article reprend l’historique et fait l’état des lieux du parc national Sahamalaza-Ile Radama, situé au nord-ouest de Madagascar. Nous nous intéressons spécifiquement à deux espèces de lémuriens emblématiques du parc ; Eulemur flavifrons et Lepilemur sahamalazensis ainsi qu’aux menaces qui pèsent sur leur écosystème. Différentes mesures ont été proposées dans le cadre d’un Plan d’Action de Conservation afin d’en améliorer la gestion et assurer la survie de ces espèces. [less ▲]

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See detailThe effects of triclosan exposure in shape changes of sheepshead minnow (Cyprinodon variegatus) during early development and metamorphosis
Schnitzler, Joseph ULg; Frederich, Bruno ULg; Dussenne, Mélanie et al

Conference (2015, August)

Thyroid hormones are essential for normal development, and for maintenance of normal physiological functions in vertebrates [1, 2]. In fish, thyroid hormones are involved in the control of osmoregulation ... [more ▼]

Thyroid hormones are essential for normal development, and for maintenance of normal physiological functions in vertebrates [1, 2]. In fish, thyroid hormones are involved in the control of osmoregulation, metabolism, somatic growth and post-hatching metamorphosis [1, 3, 4]. The regulation of thyroid hormone bioavailability in tissues and cells represents a very complex and unique web of feedback systems [2]. In fish and other vertebrates the thyroid cascade involves two components. First, thyroxine (T4) biosynthesis and secretion are largely under central control by the brain–pituitary–thyroid axis [5]. Second, there is the conversion of T4 to its biologically active form 3,5,3-triiodothyronine (T3) and its metabolism and receptor-mediated actions that seems largely to be under peripheral control in extra-thyroidal tissues [6]. The accumulation in the aquatic environment of anthropogenic chemicals, among which are endocrine disrupting chemicals (EDCs) that alter normal hormonal regulation, is having dramatic consequences for humans and wildlife. Numerous chemicals disrupt thyroid homeostasis affecting thyroid hormone (TH) synthesis and transport, and cellular uptake and metabolism [7, 8]. Triclosan (TCS) is a synthetic chlorinated phenolic compound with a generalized use as an antimicrobial and preservative in many personal care and household products [9-11]. As a result of disposal of TCS through sewage systems and insufficient/variable removal by wastewater treatment plants (WWTP) [9], widespread contamination with TCS has been detected in several countries, particularly in aquatic ecosystems, WWTP influents and effluents; sludges and biosolids; surface or ground water; drinking water; and aquatic sediments [9-11]. TCS and its metabolites have been detected in tissues and body fluids of aquatic organisms including fish, revealing they are accumulating in the food chain [9-11] and TCS has also been detected in human blood, breast milk and urine [9-11]. The structural similarity of TCS with THs [9] suggest it may have adverse effects on the thyroid system. However, little is known about the mechanisms by which TCS disrupts the thyroid axis. TCS effects on fish thyroid axis have not been investigated. It is possible, that the TCS toxic effects reported in fish embryos, larvae and adults [9-11] might be caused, at least in part, through its effect on the thyroid system. We determined how TCS affect ontogenic variations of thyroid hormones in developing sheepshead minnow larvae. Knowing that thyroid hormones are involved in somatic growth and post-hatching metamorphosis, we also tested the hypothesis that TCS alter the development of these larvae. To do this, we used landmark-based geometric morphometric methods. These methods allowed us to analyse the pure shape variations of our developing larvae, regardless orientation, position, and size. [less ▲]

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See detailDo Triclosan affect hearing development of Cyprinodon variegatus larvae?
Schnitzler, Joseph ULg; Benichou, Farida; Pinte, Nicolas et al

Poster (2015, August)

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Larval stages are ... [more ▼]

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Larval stages are particularly vulnerable to deleterious effects of endocrine disrupters because of potential impairment of fish development and behaviour. Thyroid hormones are critical to the development of the brain and auditory system. Thus, TCS could affect the development of the brain and hearing. The aims of this study were: to investigate hearing development in sheepshead minnows (Cyprinodon variegatus) using the ABR technique (Auditory Brainstem Response) and to investigate the effects of triclosan on hearing development. Exposure to TCS was conducted from fertilization of eggs on at concentrations likely to be found in the environment: 20, 50 and 100 µgl-1. We characterized previously the ontogenic variation of thyroid hormones in embryos and larvae of sheepshead minnows. We observed an increase of thyroid hormones level around the 12th and the 15th day post hatching (dph), that may be associated with the transition from larval to juvenile stage during the development of this species. We concluded, that this period could be defined as a critical exposure window to pollutants. We determined hearing thresholds for sheepshead minnows of different ages. Our sheepshead minnows show ontogenic variations in the hearing ability during their development. At 30 days post hatching, their hearing ability is quite bad, with a narrow bandwidth of detected frequencies. But their hearing ability considerably enhance during their development to reach the adult hearing ability at around 80 days post hatching when this species reach sexual maturity. So we observe during the developmental phase of this fish species clear ontogenic improvements of the hearing ability and they showed an ontogenetic expansion in the frequency bandwidth they were able to detect. The effects of TCS in this development have yet to be determined but will be fully discussed. This study proposes an interesting new endpoint in thyroid disruption research. [less ▲]

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See detailLe monopole de la légitimité démocratique
Debras, François ULg

in Revue de la Faculté de Droit de l'Université de Liège (2015), 2

Loin d’être le résultat de facteurs externes, la contestation du régime démocratique semble être avant tout le résultat d’une critique inhérente au système. Différents indicateurs mesurables viennent ... [more ▼]

Loin d’être le résultat de facteurs externes, la contestation du régime démocratique semble être avant tout le résultat d’une critique inhérente au système. Différents indicateurs mesurables viennent étayer ce que certains auteurs qualifient de « syndrome de fatigue démocratique » ou encore de « corruption du régime constitutionnel pluraliste », tels que l’augmentation de l’abstentionnisme durant les périodes électorales, une volatilité et une instabilité croissante de l’électorat et une baisse des adhésions aux organisations collectives. Fait tout aussi significatif, il semblerait que les jeunes démocraties dans les pays de l’ex-Union soviétique, d’Asie ou d’Amérique latine n’échappent pas non plus à ces phénomènes. Cette situation illustre-t-elle une perte de légitimité démocratique, une crise démocratique ou ne correspond-elle pas plutôt à une volonté citoyenne de transformer nos démocraties en élargissant et en approfondissant certaines de ses dynamiques et procédures qui lui sont propres ? Pour répondre à cette question, nous proposons de nous concentrer sur trois éléments distincts, mais étroitement liés au sein de nos démocraties européennes au XXIe siècle : le lien représentant/représenté (la représentation), la reconnaissance des libertés individuelles vis-à-vis de l’organisation collective de la société (les citoyens) et l’action du pouvoir étatique (l’État). [less ▲]

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See detailPerformance, robustness and sensitivity analysis of the nonlinear tuned vibration absorber
Detroux, Thibaut ULg; Habib, Giuseppe ULg; Masset, Luc ULg et al

in Mechanical Systems & Signal Processing (2015), 60-61

The nonlinear tuned vibration absorber (NLTVA) is a recently developed nonlinear absorber which generalizes Den Hartog׳s equal peak method to nonlinear systems. If the purposeful introduction of ... [more ▼]

The nonlinear tuned vibration absorber (NLTVA) is a recently developed nonlinear absorber which generalizes Den Hartog׳s equal peak method to nonlinear systems. If the purposeful introduction of nonlinearity can enhance system performance, it can also give rise to adverse dynamical phenomena, including detached resonance curves and quasiperiodic regimes of motion. Through the combination of numerical continuation of periodic solutions, bifurcation detection and tracking, and global analysis, the present study identifies boundaries in the NLTVA parameter space delimiting safe, unsafe and unacceptable operations. The sensitivity of these boundaries to uncertainty in the NLTVA parameters is also investigated. [less ▲]

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See detailAtmospheric circulation changes identified thanks to ground-based FTIR monitoring of hydrogen chloride (HCl)
Mahieu, Emmanuel ULg; Chipperfield, Martyn. P.; Notholt, Justus et al

Article for general public (2015)

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See detailPhysical modeling of lateral dike breaching due to overtopping
Rifai, Ismail; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in River, Coastal and Estuarine Morphodynamics, RCEM 2015 (2015, August)

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures ... [more ▼]

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures, combined with their increased vulnerability to extreme hydrological events may cause the dikes to breach, and subsequently to break. Furthermore, statistics show that flow overtopping is the main cause of dike failure, which emphasizes the need to understand thoroughly the process of breaching. Indeed, from a risk management perspective it is particularly important to have a detailed understanding of the mechanisms (e.g. internal erosion, overtopping erosion) underlying the formation of breaches due to overtopping and reliable information on flows passing through them. Conversely, the current knowledge of breaching mechanisms remains fragmented, especially because dike failure involves complex interactions between flows, materials of the structure, soil and foundations. The existing studies have addressed partially these interactions as the considered idealized dikes were generally homogenous, the piping erosion unaccounted for and the overtopping replicated in a dam-break like configuration. Yet, river embankments are subjected to high flow velocities parallel to the direction of the dike and to flow in the floodplain, which highly influence the shape of the breach and its evolution. The objective of the present work is to fill this gap. A laboratory experimental investigation is planned in the National Laboratory for Hydraulics and Environment (LNHE) of EDF R&D (France) and in the research group Hydraulics in Environmental and Civil Engineering (HECE) of the University of Liege (Belgium), reproducing realistic configurations of river dikes, accounting for the tangential flow in both main channel and floodplain. It enables thus the assessment of, on the one hand, the effect of the increase of the water level, and on the other hand, the influence of waves. The laboratory tests also consider the effect of a surface layer and composition of the dike core by testing different material mixtures. Geometry and composition of the idealized dikes are representative of typical field dikes, based on the similarity theory. [less ▲]

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See detailA study of composite laminates failure using an anisotropic gradient-enhanced damage mean-field homogenization model
Wu, Ling ULg; Sket, Federico; Molina-Aldareguia, Jon M et al

in Composite Structures (2015), 126

The failure of carbon fiber reinforced epoxy laminates is studied using an anisotropic gradient-enhanced continuum damage model embedded in a mean-field homogenization scheme. In each ply, a homogenized ... [more ▼]

The failure of carbon fiber reinforced epoxy laminates is studied using an anisotropic gradient-enhanced continuum damage model embedded in a mean-field homogenization scheme. In each ply, a homogenized material law is used to capture the intra-laminar failure. The anisotropy of the homogenized material model results from the homogenization method and from the reformulation of the non-local continuum damage theory to account for the material anisotropy. As a result the damage propagation direction in each ply is predicted with accuracy as compared to the experimental results, while the problems of losing uniqueness and strain localization, which occur in classical finite element simulations when strain softening of materials is involved, can be avoided. To model the delamination process, the hybrid discontinuous Galerkin/extrinsic cohesive law method is introduced at the ply interfaces. This hybrid method avoids the need to propagate topological changes in the mesh with the propagation of the delamination while it preserves the consistency and stability in the un-cracked interfaces. As a demonstration, open-hole coupons with different stacking sequences are studied numerically and experimentally. Both the intra- and inter-laminar failure patterns are shown to be well captured by the computational framework. [less ▲]

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See detailCharacterizing activity sequences using Profile Hidden Markov Models
Liu, Feng; Janssens, Davy; Cui, JianXun et al

in Expert Systems with Applications (2015), 42(13), 57055722

In literature, activity sequences, generated from activity-travel diaries, have been analyzed and classified into clusters based on the composition and ordering of the activities using Sequence Alignment ... [more ▼]

In literature, activity sequences, generated from activity-travel diaries, have been analyzed and classified into clusters based on the composition and ordering of the activities using Sequence Alignment Methods (SAM). However, using these methods, only the frequent activities in each cluster are extracted and qualitatively described; the infrequent activities and their related travel episodes are disregarded. Thus, to quantify the occurrence probabilities of all the daily activities as well as their sequential orders, we develop a novel process to build multiple alignments of the sequences and subsequently derive profile Hidden Markov Models (pHMMs). This process consists of 4 major steps. First, activity sequences are clustered based on a pre-defined scheme. The frequent activities along with their sequential orders are then identified in each cluster, and they are subsequently used as a template to guide the construction of a multiple alignment of the cluster of sequences. Finally, a pHMM is employed to convert the multiple alignment into a position-specific scoring system, representing the probability of each frequent activity at each important position of the alignment as well as the probabilities of both insertion and deletion of infrequent activities. By applying the derived pHMMs to a set of activity-travel diaries collected in Belgium as well as a group of mobile phone call location data recorded in Switzerland, the potential and effectiveness of the models in capturing the sequential features of each cluster and distinguishing them from those of other clusters, are demonstrated. The proposed method can also be utilized to improve activity-based transportation model validation and travel survey designs. Furthermore, it offers a wide application in characterizing a group of any related sequences, particularly sequences varying in length and with a high frequency of short sequences that are typically present in human behavior. [less ▲]

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See detailOptimization of composite structures with curved fiber trajectories
Lemaire, Etienne; Zein, Samih; Bruyneel, Michaël ULg

in Composite Structures (2015), 131

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See detailGeophysical Investigation of the Pb-Zn deposit of Plombières, Belgium
Evrard, Maxime ULg; Pirard, Eric ULg; Nguyen, Frédéric ULg

in André-mayer, anne-Sylvie; Cathelineau, Michel; Muchez, Philippe (Eds.) et al Mineral resources in a sustainable worl, proceeding, volume 5 (2015, August)

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See detailL’action du FDF dans les Régions et Communautés (1971-2014). II. Institutions bruxelloises
Lanneau, Catherine ULg

in Courrier Hebdomadaire du CRISP (2015), (2260-2261), 61

Depuis sa création, le FDF poursuit un triple objectif au plan institutionnel : assurer la solidarité entre Wallons et Bruxellois francophones, garantir les droits linguistiques des francophones de ... [more ▼]

Depuis sa création, le FDF poursuit un triple objectif au plan institutionnel : assurer la solidarité entre Wallons et Bruxellois francophones, garantir les droits linguistiques des francophones de Flandre (en particulier dans la périphérie) et bâtir une Région bruxelloise forte (avec si possible un territoire élargi). Pour promouvoir ses idées, le FDF a porté son combat non seulement sur le terrain communal et national, mais également dans les Régions et les Communautés. Le présent Courrier hebdomadaire retrace les principales lignes de force de l’action du FDF dans les organes des entités fédérées où il a été présent au cours des cinquante dernières années : le Parlement de la Communauté française, le Parlement flamand et les institutions bruxelloises. Quel rôle le FDF a-t-il joué à la Communauté française ? Quelle a été l’action de son député au Parlement flamand ? Comment s’est articulée la lutte du parti pour l’institutionnalisation d’une Région bruxelloise et, une fois celle-ci créée en 1989, dans quelle mesure y a-t-il appliqué son programme ? Le FDF a-t-il réussi à dépasser son image de parti focalisé sur les thématiques linguistiques pour se positionner en mouvement « urbain et culturel » se définissant comme « réformateur social » ? L’attention se porte sur la pratique du parti tant agissant seul qu’évoluant en partenariat avec le Rassemblement wallon ou, plus récemment, avec les libéraux. [less ▲]

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See detailL’action du FDF dans les Régions et Communautés (1971-2014). I. Le Parlement de la Communauté française et le Parlement flamand
Lanneau, Catherine ULg

in Courrier Hebdomadaire du CRISP (2015), (2258-2259), 60

Depuis sa création, le FDF poursuit un triple objectif au plan institutionnel : assurer la solidarité entre Wallons et Bruxellois francophones, garantir les droits linguistiques des francophones de ... [more ▼]

Depuis sa création, le FDF poursuit un triple objectif au plan institutionnel : assurer la solidarité entre Wallons et Bruxellois francophones, garantir les droits linguistiques des francophones de Flandre (en particulier dans la périphérie) et bâtir une Région bruxelloise forte (avec si possible un territoire élargi). Pour promouvoir ses idées, le FDF a porté son combat non seulement sur le terrain communal et national, mais également dans les Régions et les Communautés. Le présent Courrier hebdomadaire retrace les principales lignes de force de l’action du FDF dans les organes des entités fédérées où il a été présent au cours des cinquante dernières années : le Parlement de la Communauté française, le Parlement flamand et les institutions bruxelloises. Quel rôle le FDF a-t-il joué à la Communauté française ? Quelle a été l’action de son député au Parlement flamand ? Comment s’est articulée la lutte du parti pour l’institutionnalisation d’une Région bruxelloise et, une fois celle-ci créée en 1989, dans quelle mesure y a-t-il appliqué son programme ? Le FDF a-t-il réussi à dépasser son image de parti focalisé sur les thématiques linguistiques pour se positionner en mouvement « urbain et culturel » se définissant comme « réformateur social » ? L’attention se porte sur la pratique du parti tant agissant seul qu’évoluant en partenariat avec le Rassemblement wallon ou, plus récemment, avec les libéraux. [less ▲]

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See detailLes recherches sur la médecine dans l’Égypte gréco-romaine au Centre de Documentation de Papyrologie Littéraire (CEDOPAL) de l’Université de Liège
Marganne, Marie-Hélène ULg

in Histoire des Sciences Médicales (2015, August), 49(2), 233-237

The paper presents the research on medicine in Greco-Roman Egypt conducted in the last forty years at the Centre de Documentation de Papyrologie Littéraire (CEDOPAL) at the University of Liège. It ... [more ▼]

The paper presents the research on medicine in Greco-Roman Egypt conducted in the last forty years at the Centre de Documentation de Papyrologie Littéraire (CEDOPAL) at the University of Liège. It describes the main results obtained by deciphering, editing, translating and commenting Greek and Latin medical papyri, be they literary, documentary or magical. [less ▲]

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See detailChemical spying in coral reef fish larvae at recruitment
Roux, Natacha; Brooker, Rohan M.; Lecellier, Gaël et al

in Comptes Rendus Biologies (2015)

When fish larvae recruit back to a reef, chemical cues are often used to find suitable habitat or to find juvenile or adult conspecifics. We tested if the chemical information used by larvae was ... [more ▼]

When fish larvae recruit back to a reef, chemical cues are often used to find suitable habitat or to find juvenile or adult conspecifics. We tested if the chemical information used by larvae was intentionally produced by juvenile and adult conspecifics already on the reef (communication process) or whether the cues used result from normal biochemical processes with no active involvement by conspecifics (‘‘spying’’ behavior by larvae). Conspecific chemical cues attracted the majority of larvae (four out of the seven species tested); although while some species were equally attracted to cues from adults and juveniles (Chromis viridis, Apogon novemfasciatus), two exhibited greater sensitivity to adult cues (Pomacentrus pavo, Dascyllus aruanus). Our results indicate also that spying cues are those most commonly used by settling fishes (C. viridis, P. pavo, A. novemfasciatus). Only one species (D. aruanus) preferred the odour of conspecifics that had had visual contact with larvae (communication). [less ▲]

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