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Peer Reviewed
See detailFish growth hormones
Renard, A.; Lecomte, C.; Rentier-Delrue, Françoise ULg et al

in Seminar on Use of Somatotropin in Livestock productio (1988)

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See detailFish habitat selection in a large hydropeaking river: Strong individual and temporal variations revealed by telemetry
Capra, Hervé; Plichard, Laura; Bergé, Julien et al

in Science of the Total Environment (2017), 578

Modeling individual fish habitat selection in highly variable environments such as hydropeaking rivers is required for guiding efficient management decisions. We analyzed fish microhabitat selection in ... [more ▼]

Modeling individual fish habitat selection in highly variable environments such as hydropeaking rivers is required for guiding efficient management decisions. We analyzed fish microhabitat selection in the heterogeneous hydraulic and thermal conditions (modeled in two-dimensions) of a reach of the large hydropeaking Rhône River locally warmed by the cooling system of a nuclear power plant. We used modern fixed acoustic telemetry techniques to survey 18 fish individuals (five barbels, six catfishes, seven chubs) signaling their position every 3 s over a three-month period. Fish habitat selection depended on combinations of current microhabitat hydraulics (e.g. velocity, depth), past microhabitat hydraulics (e.g. dewatering risk or maximum velocities during the past 15 days) and to a lesser extent substrate and temperature. Mixed-effects habitat selection models indicated that individual effects were often stronger than specific effects. In the Rhône, fish individuals appear to memorize spatial and temporal environmental changes and to adopt a “least constraining” habitat selection. Avoiding fast-flowing midstream habitats, fish generally live along the banks in areas where the dewatering risk is high. When discharge decreases, however, they select higher velocities but avoid both dewatering areas and very fast-flowing midstream habitats. Although consistent with the available knowledge on static fish habitat selection, our quantitative results demonstrate temporal variations in habitat selection, depending on individual behavior and environmental history. Their generality could be further tested using comparative experiments in different environmental configurations. [less ▲]

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See detailFish introduction is a major cause of paedomorphosis extinction in European newts (Triturus spp.)
Džukić, Georg; Ćirović, Ruža; Denoël, Mathieu ULg et al

in Froglog (2005), 69

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See detailFish larvae prefer coral over algal water cues: implications of coral reef degradation
Lecchini, David; Waqalevu, Viliam; Parmentier, Eric ULg et al

in Marine Ecology. Progress Series (2013), 475

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See detailFish lateral system is required for accurate control of shoaling behaviour
Faucher, Karine ULg; Parmentier, Eric ULg; Becco, Christophe ULg et al

Conference (2010)

In teleost fishes, the lateral system is assumed to contribute, among other roles, to maintaining schooling behaviour. Sight is also assumed to play a role in schooling, as fish with a cut lateral line do ... [more ▼]

In teleost fishes, the lateral system is assumed to contribute, among other roles, to maintaining schooling behaviour. Sight is also assumed to play a role in schooling, as fish with a cut lateral line do not stop schooling unless they are also blinded. This conclusion, however, was based on experiments where only the trunk lateral line was inactivated, leaving the head lateral system intact. Here the aim was to test how inactivation of the whole lateral system affects the fish shoaling behaviour. Groups of firehead tetras, Hemigrammus bleheri, were video-recorded before and after inactivation of their whole lateral system with aminoglycoside antibiotics (and also in sham-treated specimens). Shoaling behaviour was characterized by: nearest distance to the first, second, and third neighbour, shoal radius, shoal order parameter, and the number of collisions between individuals. SEM observations showed damage to most superficial neuromasts as a result of antibiotic treatment. Importantly, the antibiotic-treated fish proved unable to maintain a shoal. After the end of the treatment, however, they recovered both a normal tissue morphology and normal shoaling behaviour within about a month. The lateral system is thus more crucial to shoaling behaviour than previously believed. [less ▲]

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See detailFish lateral system is required for accurate control of shoaling behaviour
Faucher, Karine ULg; Parmentier, Eric ULg; Becco, Christophe ULg et al

in Animal Behaviour (2010), 79

In teleost fishes, the lateral system is assumed to contribute, among other roles, to maintaining schooling behaviour. Sight is also assumed to play a role in schooling, as fish with a cut lateral line do ... [more ▼]

In teleost fishes, the lateral system is assumed to contribute, among other roles, to maintaining schooling behaviour. Sight is also assumed to play a role in schooling, as fish with a cut lateral line do not stop schooling unless they are also blinded. This conclusion, however, is based on experiments where only the trunk lateral line was inactivated, leaving the head lateral system intact. We investigated how inactivation of the whole lateral system affects fish shoaling behaviour. Groups of firehead tetras, Hemigrammus bleheri, were videorecorded before and after inactivation of their whole lateral system with aminoglycoside antibiotics (and also in sham-treated specimens). Shoaling behaviour was characterized by nearest distance to the first, second and third neighbours, shoal radius, shoal order parameter and the number of collisions between individuals. Scanning electron microscope observations showed damage to most superficial neuromasts as a result of antibiotic treatment. Importantly, the antibiotic-treated fish proved unable to maintain a shoal. After the end of the treatment, however, they recovered both a normal tissue morphology and normal shoaling behaviour within about a month. The lateral system is thus more crucial to shoaling behaviour than previously believed. [less ▲]

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See detailThe Fish Migrate and so Must We': the Relationship between International and Internal Environmental Mobility in a Senegalese Fishing Community
Zickgraf, Caroline ULg

Conference (2015, April)

In 2008, the UN designated Saint-Louis “the city most threatened by rising sea levels in the whole of Africa”. The people of Guet Ndar, a densely populated fishing quarter, are coping with environmental ... [more ▼]

In 2008, the UN designated Saint-Louis “the city most threatened by rising sea levels in the whole of Africa”. The people of Guet Ndar, a densely populated fishing quarter, are coping with environmental challenges on two fronts: 1) coastal erosion and intensifying storms have destroyed sea-front homes, and, 2) overfishing and climate change’s maritime impacts are making local fishing less feasible as a livelihood strategy. Based on a local case study, this paper examines Guet Ndarian migration as an adaptive response to environmental risks and more specifically climate change: 1) through the intensification of fishing migration to Mauritania, and 2) through home construction on the mainland away from the encroaching sea. Although these population movements respond to different environmental challenges, this paper identifies their enmeshment as the former facilitates the latter. Furthermore, it embeds these migratory dynamics in their socio-economic context and applies mobility and transnational paradigms to environmentally vulnerable areas. [less ▲]

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See detailFish responses to artificial flow and water temperature variability in a large river (Rhône, France)
Capra, Hervé; Ovidio, Michaël ULg; Pella, Hervé et al

in Proceedings of the 9th International Conference on Ecohydraulics (2012, September)

Understanding fine scale behavioural responses of fish to changes in abiotic characteristics of habitat, such as flow variability, is an interesting innovative issue to improve river management in highly ... [more ▼]

Understanding fine scale behavioural responses of fish to changes in abiotic characteristics of habitat, such as flow variability, is an interesting innovative issue to improve river management in highly disturbed aquatic environments. For example, in the Rhône River (France), important hydrology and thermal contrasts are mainly explicated by the succession of dams and nuclear power plants. The main aim of our study was to describe fish behaviour in term of movements and habitat use as responses to habitat variability due to the production of peaking electricity and temperature heterogeneity (natural or due to a nuclear power plant release). Fixed telemetry system (accuracy of few square meters; Hydroacoustic Technology Inc.) enabled to define individual fish behavior during different short habitat variability configuration (flow increase, flow decrease, temperature increase....). We then recorded at a local scale continuous movements of n=61 fish during short term (lower than day) habitat variability. The study was conducted in a 2 km long river stretch, from July to September 2009. Abiotic conditions (temperature, depth, velocity or substrate) were simulated (with an accuracy comparable with fish positioning accuracy) every where at any time (i.e. for any discharge) using a hydraulic 2D model calibrated and validated for the whole discharge range observed during the experiment. Three main species were represented : two native cyprinids, chub (Squalius cephalus) and barbel (Barbus barbus), and an invasive species, wels catfish (Silurus glanis). Fish mobility and habitat use were studied to describe changes in behavior associated with changes of abiotic conditions. The separate effects of each environmental factors (discharge, temperature, photoperiod) and their interactions on fish behavioral responses were studied. Finally, variability of fish habitat preferences were estimated to refine understanding of observed behaviors. The different results highlighted the advantages and limitations of the telemetry acoustic system in a large river to address fish displacement in response to discharge and temperature variability. They also emphasized the necessity of a 2D hydrodynamic model to understand fish behaviour. [less ▲]

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See detailThe Fisher Information Matrix as a Relevant Tool for Sensor Selection in Engine Health Monitoring
Borguet, Sébastien ULg; Léonard, Olivier ULg

in International Journal of Rotating Machinery (2008), 2008

Engine health monitoring has been an area of intensive research for many years. Numerous methods have been developed with the goal of determining a faithful picture of the engine condition. On the other ... [more ▼]

Engine health monitoring has been an area of intensive research for many years. Numerous methods have been developed with the goal of determining a faithful picture of the engine condition. On the other hand, the issue of sensor selection allowing an efficient diagnosis has received less attention from the community. The present contribution revisits the problem of sensor selection for engine performance monitoring within the scope of information theory. To this end, a metric that integrates the essential elements of the sensor selection problem is defined from the Fisher information matrix. An example application consisting in a commercial turbofan engine illustrates the enhancement that can be expected from a wise selection of the sensor set. [less ▲]

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See detailFisheries reforms and right-based fisheries: insights from community fisheries across Cambodia
Chap, Sreyphea; Touch, Panha; Diepart, Jean-Christophe ULg

E-print/Working paper (2016)

The working paper uses a right-based approach to examine recent wave of reforms in the Cambodian fisheries sector and what these reforms mean for community fisheries management.

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See detailFissuration de dépôts durs à base de Ni et de Co en Laser Cladding
Montrieux, Henri-Michel ULg; Lecomte-Beckers, Jacqueline ULg

Report (2010)

Le rapport concerne l'étude de la fissuration de dépôts durs en Ni-Cr-Fe-B-Si réalisés par Laser Cladding. Il est montré que la fissuration est provoquée par la présence de contraintes mécaniques ... [more ▼]

Le rapport concerne l'étude de la fissuration de dépôts durs en Ni-Cr-Fe-B-Si réalisés par Laser Cladding. Il est montré que la fissuration est provoquée par la présence de contraintes mécaniques résiduelles d'origine thermique et on se trouve face à un phénomène de fissuration à froid. Le travail comporte également la comparaison de 4 nuances de poudre différentes utilisées en Laser Cladding au niveau du coefficient de dilatation thermique et des microstructures. La présence de composés céramiques (borure ou carbure) de nature pro-eutectique a pour effet de diminuer le coefficient de dilatation mais d'augmenter la fragilité. Le rôle du coefficient de dilatation thermique dans la fissuration semble être moins important que la nature de la microstructure en elle-même. Le choix de nuances présentant une structure hypo-eutectique et une haute dureté semble être pertinent en ce qui concerne l'établissement d'un compromis entre la dureté et la résilience de ces matériaux particuliers. [less ▲]

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See detailFissures et accrocs du modèle idéologique de l'Egypte ancienne
Winand, Jean ULg

Conference given outside the academic context (2015)

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See detailFistula plug in fistulising ano-perineal Crohn's disease: a randomised controlled trial
Senéjoux, A.; Siproudhis, L.; Abramowitz, L. et al

in Journal of Crohn's and Colitis [=JCC] (2015)

Detailed reference viewed: 17 (0 ULg)
Peer Reviewed
See detailLes fistules cholécysto-cholédociennes. Présentation d'un cas et revue de la littérature.
Defraigne, Jean-Olivier ULg; Bonnet, Pierre ULg; Meurisse, Michel ULg et al

in Acta Gastro-Enterologica Belgica (1986), IL(Septembre-Octobre),

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See detailFit of single tooth zirconia copings: comparison between various manufacturing processes.
Grenade, Charlotte ULg; MAINJOT, Amélie ULg; Vanheusden, Alain ULg

in Journal of Prosthetic Dentistry (2011), 105(4), 249-55

STATEMENT OF PROBLEM: Various CAD/CAM processes are commercially available to manufacture zirconia copings. Comparative data on their performance in terms of fit are needed. PURPOSE: The purpose of this ... [more ▼]

STATEMENT OF PROBLEM: Various CAD/CAM processes are commercially available to manufacture zirconia copings. Comparative data on their performance in terms of fit are needed. PURPOSE: The purpose of this in vitro study was to compare the internal and marginal fit of single tooth zirconia copings manufactured with a CAD/CAM process (Procera; Nobel Biocare) and a mechanized manufacturing process (Ceramill; Amann Girrbach). MATERIAL AND METHODS: Abutments (n=20) prepared in vivo for ceramic crowns served as a template for manufacturing both Procera and Ceramill zirconia copings. Copings were manufactured and cemented (Clearfil Esthetic Cement; Kuraray) on epoxy replicas of stone cast abutments. Specimens were sectioned. Nine measurements were performed for each coping. Over- and under-extended margins were evaluated. Comparisons between the 2 processes were performed with a generalized linear mixed model (alpha=.05). RESULTS: Internal gap values between Procera and Ceramill groups were not significantly different (P=.13). The mean marginal gap (SD) for Procera copings (51(50) mum) was significantly smaller than for Ceramill (81(66) mum) (P<.005). The percentages of over- and under-extended margins were 43% and 57% for Procera respectively, and 71% and 29% for Ceramill. CONCLUSIONS: Within the limitations of this in vitro study, the marginal fit of Procera copings was significantly better than that of Ceramill copings. Furthermore, Procera copings showed a smaller percentage of over-extended margins than did Ceramill copings. [less ▲]

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See detailFitness And Genetic Variation Of Viola Calaminaria, An Endemic Metallophyte: Implications Of Population Structure And History
Bizoux, Jean-Philippe ULg; Daïnou, Kasso ULg; Raspe, O. et al

in Plant Biology (2008), 10(6), 684-693

We investigated variations in genetic diversity and plant fitness in a rare endemic metallophyte of calamine soils, Viola calaminaria, in relation to population size, population connectivity and ... [more ▼]

We investigated variations in genetic diversity and plant fitness in a rare endemic metallophyte of calamine soils, Viola calaminaria, in relation to population size, population connectivity and population history in order to evaluate and discuss potential conservation strategies for the species. Mean population genetic diversity (Hs = 0.25) of V. calaminaria was similar to endemic non-metallophyte taxa. Twenty-one per cent of the genetic variation was partitioned among populations and a low (9%) but significant differentiation was found among geographical regions. Our results did not support the hypothesis that the acquisition of metal tolerance may result in reduced genetic diversity, and suggested that strict metallophytes do not exhibit higher inter-population differentiation resulting from scattered habitats. There were no relationships between population genetic diversity and population size. Significant correlations were found between plant fitness and (i) population size and (ii) connectivity index. Recently-founded populations exhibited the same level of genetic diversity as ancient populations and also possessed higher plant fitness. There was no indication of strong founder effects in recently-established populations. The results suggest that the creation of habitats through human activities could provide new opportunities for conservation of this species. [less ▲]

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