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See detailEtude comparée des parades sexuelles de quelques espèces de chéloniens: Pelomedusa s. subrufa (Lacépède), Sternotherus minor (Agassiz) et Kinixys belliana nogueyi (Bell)
Bels, Vincent; Libois, Roland ULg

in Cahiers d'Ethologie (1983), 3(1), 39-58

Next to a short analysis of the sexual interactions and the relative importance of the stimulation kinds performed with each behaviour pattern, we analyse the observed behavioural sequences in courtship ... [more ▼]

Next to a short analysis of the sexual interactions and the relative importance of the stimulation kinds performed with each behaviour pattern, we analyse the observed behavioural sequences in courtship and mating behaviour of three chelonian's species: Pelomedusa s. subrufa, Sternotherus minor and Kinixys belliana nogueyi. The study of the behavioural sequences emphasizes the great fluctiation between the exhibited behaviour patterns and specifies the means leading to the female's stabilization. The sexual behaviours (knowed from this study or the litterature) of P.s.subrufa, S. minor, K. belliana nogueyi, Geochelone carbonaria, Testudo g. graeca, Emys orbicularis, Chrysemys scripta elegans, Chemmys nigricans and Meosemys grandis were submitted to a discriminant analysis to establish certain phylogenetic relations by use of behavioural criteria. We emphasize here the difficulties of the interpretation of this lethod. However, we establish a relative ratification of the phylogeny founded on morphological characters. [less ▲]

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See detailEtude comparée du comportement de cour de Triturus alpestris alpestris (Laurenti, 1768) et Triturus alpestris cyreni (Wolterstorff, 1932) : approche évolutive
Denoël, Mathieu ULg

Master's dissertation (1996)

The species concept in the animal world is very abstract. With diverse methods scientists try to place boundaries between species. But this is generally theoretical. Indeed species are in continuous ... [more ▼]

The species concept in the animal world is very abstract. With diverse methods scientists try to place boundaries between species. But this is generally theoretical. Indeed species are in continuous evolution, located more regularly between two evolutionary categories than inside a well-defined one. In this study we are interested by the courtship of two allopatric subspecies of the Alpine newt, Triturus alpestris alpestris and T. a. cyreni. We investigate the behaviour of two closely related taxa, in experimental conditions, to display the basis of behaviour evolution and isolating mechanisms prominently. We have identified 24 behaviours in the male display and principally 3 in the female (negative, static, positive). Sexual encounter will be divided in four stages: orientation during which animals are meeting, fan and lean-in exhibition phases during which the male displays and the spermatophore transfer sequence where the male deposits a spermatophore and displays also. The qualitative differences between subspecies are weak and concern principally amplitude of movements. From a qualitative level some differences were underlined. So T. a. alpestris touches the female with its snout frequently, whereas T. a. cyreni whips more often. The two subspecies do not use the same tactic with a non-responsive female. Indeed the T. a. alpestris male can easily enter in spermatophore transfer phase without the positive response of female. In order to attract the latter, he executes worm-like movements: in this way he lures a negative female. On the contrary, T. a. cyreni rarely deposits a spermatophore when the female is not receptive. It therefore makes very little use of the lure system. The analysis of male behaviours in relation with female response have allowed us to establish a model which assumes that some behaviours are exhibited by the male only when its motivation and that of the female go beyond a particular level. Some stereotyped behaviours (e.g. distal fan) concern movements whose amplitude is variable. We think that this movement modulation could be the foundation of a behaviour evolution and isolating mechanism. The female is indeed sensitive to these variations: in this way communication is possible between transmitter and receiver. The new variants problem is thus resolved. The fanning frequencies vary with temperature. They are weak at low temperatures. We consider this modulation as an adaptation to extreme and unpredictable habitats, e.g. in high altitude lakes and temporary ponds. The observed behavioural differences are in a lower level than between separate species, like T. helveticus and T. vulgaris. Moreover sperm transfer is likely between the two taxa. In conclusion the present data confirm the existence of two distinct subspecies T. a. alpestris and T. a. cyreni as detected by previous authors using allozyme and osteological analysis. [less ▲]

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See detailEtude comparée du comportement de cour de Triturus alpestris alpestris (Laurenti, 1768) et Triturus alpestris cyreni (Wolterstorff, 1932) : approche évolutive.
Denoël, Mathieu ULg

Book published by Cahiers d'Ethologie (1996)

The species concept in the animal world is very abstract. With diverse methods scientists try to place boundaries between species. But this is generally theoretical. Indeed species are in continuous ... [more ▼]

The species concept in the animal world is very abstract. With diverse methods scientists try to place boundaries between species. But this is generally theoretical. Indeed species are in continuous evolution, located more regularly between two evolutionary categories than inside a well-defined one. In this study we are interested by the courtship of two allopatric subspecies of the Alpine newt, Triturus alpestris alpestris and T. a. cyreni. We investigate the behaviour of two closely related taxa, in experimental conditions, to display the basis of behaviour evolution and isolating mechanisms prominently. We have identified 24 behaviours in the male display and principally 3 in the female (negative, static, positive). Sexual encounter will be divided in four stages: orientation during which animals are meeting, fan and lean-in exhibition phases during which the male displays and the spermatophore transfer sequence where the male deposits a spermatophore and displays also. The qualitative differences between subspecies are weak and concern principally amplitude of movements. From a qualitative level some differences were underlined. So T. a. alpestris touches the female with its snout frequently, whereas T. a. cyreni whips more often. The two subspecies do not use the same tactic with a non-responsive female. Indeed the T. a. alpestris male can easily enter in spermatophore transfer phase without the positive response of female. In order to attract the latter, he executes worm-like movements: in this way he lures a negative female. On the contrary, T. a. cyreni rarely deposits a spermatophore when the female is not receptive. It therefore makes very little use of the lure system. The analysis of male behaviours in relation with female response have allowed us to establish a model which assumes that some behaviours are exhibited by the male only when its motivation and that of the female go beyond a particular level. Some stereotyped behaviours (e.g. distal fan) concern movements whose amplitude is variable. We think that this movement modulation could be the foundation of a behaviour evolution and isolating mechanism. The female is indeed sensitive to these variations: in this way communication is possible between transmitter and receiver. The new variants problem is thus resolved. The fanning frequencies vary with temperature. They are weak at low temperatures. We consider this modulation as an adaptation to extreme and unpredictable habitats, e.g. in high altitude lakes and temporary ponds. The observed behavioural differences are in a lower level than between separate species, like T. helveticus and T. vulgaris. Moreover sperm transfer is likely between the two taxa. In conclusion the present data confirm the existence of two distinct subspecies T. a. alpestris and T. a. cyreni as detected by previous authors using allozyme and osteological analysis. [less ▲]

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See detailEtude complémentaire de la cytotoxicite de la mélinonine F, alcaloide dérive de la beta-carboline
Bassleer, Roger ULg; Marnette, J. M.; Wiliquet, P. et al

in Planta Medica (1983), 49(11), 158-161

The cellular effects of melinonine F, an alkaloid isolated from STRYCHNOS MELINONIANA (South America) and STRYCHNOS USAMBARENSIS (Central Africa), are analysed in cancer or normal cells in culture. A ... [more ▼]

The cellular effects of melinonine F, an alkaloid isolated from STRYCHNOS MELINONIANA (South America) and STRYCHNOS USAMBARENSIS (Central Africa), are analysed in cancer or normal cells in culture. A cytotoxic action is noted in both types of cells, at least for relatively high concentrations. These effects are probably due to interaction of the drug with chromatin. Physico-chemical analysis demonstrates partial intercalation of melinonine F on pure DNA IN VITRO. [less ▲]

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See detailEtude complémentaire relative aux profils d'accessibilité - profils de mobilité
Daxhelet, Delphine; Kessler, Laurent; Lambotte, Jean-Marc ULg et al

Report (2002)

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See detailEtude complète d'une unité de sauvetage fluvial de grande puissance
Marchal, Jean ULg; Rodriguez, S.

Report (1980)

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See detailEtude contrastive de la notion temps/aspect dans les langues indo-européennes
Mouton, Charles ULg

in Slavica Gandensia (1998), (25/1), 29-41

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See detailEtude couplée pharmacocinétique et urodynamique de l'administration orale de différents dosages de phenylpropanolamine chez la chienne continente.
Noël, Stéphanie ULg

Master of advanced studies dissertation (2007)

The goal of this study is to establish the pharmacokinetic characteristics of oral administration of phenylpropanolamine at different dosages (1.5 mg/Kg once a day and three times a day), in continent ... [more ▼]

The goal of this study is to establish the pharmacokinetic characteristics of oral administration of phenylpropanolamine at different dosages (1.5 mg/Kg once a day and three times a day), in continent bitches, and to assess the associated urodynamic effects. The influence of phenylpropanolamine on systemic arterial pressure and heart rate is also studied. Maximal concentration appears two hours after the administration of phenylpropanolamine. Since the half-life lasts four hours and due to a mechanism of accumulation, a repeated daily administration induces an increase of the maximal concentration after each administration. After one week of a single administration of phenylpropanolamine per day, an increased urethral resistance and functional profile length are observed at the time of maximal concentration. This increase could explain the successful treatment of incontinent bitches with a single daily administration of phenylpropanolamine. However, a repeated administration of phenylpropanolamine three times a day does not increase the urethral resistance, probably after desensitization of the adrenergic receptors. The increase in arterial pressure after the administration of phenylpropanolamine is compensated by a decreased heart rate occurring at the time of maximal concentration. [less ▲]

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See detailEtude cristallographique à haute résolution des interactions d’une enzyme psychrophile avec des analogues de substrat.
Aghajari, Nushin; Feller, Georges ULg; Payan, Françoise et al

Poster (1996)

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See detailEtude critique de quelques formulations de la théorie des coques en vue de l'application aux éléments finis
Debongnie, Jean-François ULg

Report (1986)

Surface geometry and shell geometry, in the frame of general tensor calculus. Fundamentals of the theory of thin shells. Expressing strains from curvilinear components of the displacements. Applicability ... [more ▼]

Surface geometry and shell geometry, in the frame of general tensor calculus. Fundamentals of the theory of thin shells. Expressing strains from curvilinear components of the displacements. Applicability of the preceeding theory to finite elements. Expressing strains from the cartesian components of the displacements. Moderate rotation theory (curvilinear components). Moderate rotation theory (cartesian components). Quasi-plane and almost-plane shells. Shells with shearing strains (cartesian components). Shells with shear strains (curvilinear components). Moderate rotations of a shell with shear strains (curvilinear components). Re-interpretation and generaisation of Marguerre shallow shells. Conical shells. Quasi-conical shells. Axisymmetrical shells in cylindrical components. Annex : an introduction of the elasticity theory in curvilinear coordinates.Bibliography [less ▲]

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See detailEtude critique des liens de la théorie de l'art à l'idée platonicienne : de l'esthétique idéaliste (Cassirer/Panofsky) à la crise de l'Idée (Didi-Huberman)
Hagelstein, Maud ULg

in Leclercq, Bruno; Colette, Bernard (Eds.) L'Idée de l'Idée. Eléments de l'histoire d'un concept (2012)

Quelle place laisse-t-on généralement à l’Idée dans le champ de la création artistique? Depuis la Renaissance, les théoriciens de l’art reconnaissent volontiers son rôle fondateur. Transformée par les ... [more ▼]

Quelle place laisse-t-on généralement à l’Idée dans le champ de la création artistique? Depuis la Renaissance, les théoriciens de l’art reconnaissent volontiers son rôle fondateur. Transformée par les bouleversements culturels et théoriques du Quattrocento, la représentation artistique moderne semble subir l’autorité de l’Idée. Telle est d’ailleurs la conception à laquelle se réfèrent encore Ernst Cassirer et Erwin Panofsky: aucun signe n’est laissé au hasard dans les oeuvres, l’artiste participant au déploiement de la pensée rationnelle. Le dialogue de ces auteurs à propos de l’Idée platonicienne servira ici de cadre à la réflexion. Guidé par les principes du néokantisme, le débat qui anime les deux penseurs dans les années 20 (à l’époque, Cassirer et Panofsky sont collègues à l’Université de Hambourg) marquera profondément le développement ultérieur de l’histoire de l’art. Pour cette raison au moins, il importe de reprendre ici les arguments principaux de leur démonstration à deux voix. Aujourd’hui, pourtant, la création artistique n’est plus automatiquement rapportée au concept d’Idée. Rares sont les théoriciens qui voient encore l’objet artistique comme la seule matérialisation d’une entité intelligible séparée. Le couple matière/forme semble lui-même dépassé. Et, de manière générale, la plupart des catégories esthétiques sont mises en cause par les nouvelles définitions de l’image. Parmi ceux qui résistent à la tendance «idéalisante» de l’histoire de l’art, Georges Didi-Huberman est probablement celui qui inscrit le plus explicitement son propos dans le débat initié par Cassirer et Panofsky. [less ▲]

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See detailEtude critique du rôle du sodium dans l'hypertension artérielle
Krzesinski, Jean-Marie ULg

Thèse d’agrégation de l’enseignement supérieur (1993)

Une partie de nos résultats expérimentaux et cliniques a fait l'objet d'un doctorat en Sciences Cliniques défendu en janvier 1986. La poursuite de ces travaux et le développement de nouvelles techniques ... [more ▼]

Une partie de nos résultats expérimentaux et cliniques a fait l'objet d'un doctorat en Sciences Cliniques défendu en janvier 1986. La poursuite de ces travaux et le développement de nouvelles techniques nous ont donné l'occasion de reprendre ce sujet et d'en approfondir la matière, avec un recul que nous espérons bénéfique. [less ▲]

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See detailEtude critique du taux de saturation en phosphore dans des sols agricoles en région wallonne en tant qu’indicateur de bonnes pratiques en matière de fertilisation phosphorée
Renneson, Malorie ULg; Vandenberghe, Christophe ULg; Marcoen, Jean Marie ULg

in Marcoen, Jean Marie; Lambert, Richard; Vandenberghe, Christophe (Eds.) et al Programme de gestion durable de l’azote en agriculture wallonne – Rapport d’activités annuel intermédiaire 2008 des membres scientifiques de la Structure d’encadrement Nitrawal. (2008)

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