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Mise au point d’un protocole de multiplication in vitro de Jatropha curcas L. en vue d’une application à grande échelleMedza Mve, Samson Daudet ![]() Doctoral thesis (2013) Jatropha curcas L. is a wild plant, that emerged as a source of energy for biodiesel production. It has acquired significant economic potential as it does not compete with the edible oil supplies ... [more ▼] Jatropha curcas L. is a wild plant, that emerged as a source of energy for biodiesel production. It has acquired significant economic potential as it does not compete with the edible oil supplies. Realizing its importance, in vitro multiplication methods have been established to meet the demand of large scale supply of superior clones. In order to improve the in vitro multiplication rate (number of shoots/explant/subculture/three weeks) of J. curcas, axillary nodes taken from young plants of two accessions (originating from Cameroon and Senegal) have been cultivated for three weeks on a Murashige and Skoog (1962) medium (MS) supplemented with 8.87 µM BAP, 4.92 µM IBA, and 30 g/l sucrose at pH 5.7±0.1, and solidified with 0.7% agar. The shoots obtained from each original explant were then transferred to a multiplication media consisting of MS medium supplemented with 2.21 to 8.9 μM BA or 2.21 to 8.9 μM kinetin in combination with 2.46 μM IBA. Each combination was completed with 12.2 mg.l-1 adenine sulfate and 25 mg.l-1 of glutamine. The best multiplication rate was obtained for the PM medium containing 6.65 μM BA and 2.46 μM IBA. The mean multiplication rate is 8.1 shoots per explant during the 7 following subcultures. Leafy shoots obtained have been rooted in a medium containing half of the major mineral and minor mineral components of MS supplemented with 5.7 μM IBA, then acclimated with a survival rate of 97%. With the aim of finding a more efficient production protocol practicable on a large-scale, an alternative method has been developed to regenerate whole plants of J. curcas from nodes via the induction of buds aggregates. Histological observation shows that bud aggregates are simultaneously formed through axillary budding and adventitious regeneration of buds. These buds are elongated in MS medium supplemented with 2.21 µM BA, 5.70 µM IAA (indole-3-acetic acid) and 15 mg.l-1 L arginine. The leafy stems are then rooted on MS containing 2.46 µM IBA, 2% sucrose, and 0.7% agar. The entire process takes 14 weeks with 98% plants survival after acclimatization. We obtain a multiplication rate of 13 buds per explant per subculture. This protocol is more efficient than previously known protocols. [less ▲] Detailed reference viewed: 9 (0 ULg) Influence of the mode of walk on walking speed in multiple sclerosis: are you walking comfortably?PHAN BA, Remy ; DELRUE, Gaël ; Pierard, Sébastien et alPoster (2013, June 10) Introduction : Walking speed (WS) is the most frequent gait variable taken into account when measuring gait dysfunction in neurological diseases. Influences of the mode of walk instructed to the subject ... [more ▼] Introduction : Walking speed (WS) is the most frequent gait variable taken into account when measuring gait dysfunction in neurological diseases. Influences of the mode of walk instructed to the subject, i.e. « as fast as possible » (AFAP) or « at a comfortable pace » (PrP) have not been well characterized in multiple sclerosis (MS). Objectives : to compare those 2 mode of walk in a population of persons with MS (pMS) and healthy volunteers (HV). Methods: WS was measured with a new automated device along a 25 foot distance (T25FW) as part of a multimodal evaluation of gait in an MS ambulatory department. Results: Baseline demographics between HV and pMS were comparable. Our first results demonstrate that (i) WS is obviously significantly higher in AFAP than in PrP both for pMS and HV (p < 0.001 for all comparisons) and (ii) the relative difference between AFAP and PrP WS is significantly higher in HV than in pMS (p < 0.001). The AFAP-PrP WS correlation is higher in pMS (r = 0.87, p < 0.001) than in HV (r = 0.51, p < 0.001). Finally, the relative difference between AFAP and PrP WS is significantly and negatively correlated with the PrP WS in HV (r = -0.41, p < 0.001) and pMS with mild to moderate disability (EDSS 0-3.5, r = -0.49, p < 0.01) but not in pMS with high disability (EDSS 4-5.5, r = 0.008). Conclusions : these results suggests that heatlhy subjects have access to a higher range of PrP WS than pMS and questions the regulation of PrP WS that might be under psychological or behavioural influences. The demonstration of a lower PrP-AFAP difference in MS suggests that pMS are either adopting a natural WS closer to their maximum WS, or alternatively that they can’t reach their maximum WS because of neurological impairments. Our results also emphasize the importance of the instructed mode of walk in the quantification of gait disorders both for routine clinical practice and clinical trials. [less ▲] Detailed reference viewed: 44 (10 ULg) De la perversion au pervers ; du sexuel à l’adaptatifEnglebert, Jérôme ![]() Scientific conference (2013, June 08) Detailed reference viewed: 9 (0 ULg) Proposition de nouveaux indices de détection de patrons de réponses inappropriés dans le contexte des enquêtes et des épreuves d’évaluation des apprentissages; ; Magis, David ![]() Conference (2013, June 07) Il n’est pas rare de voir des étudiants répondre de façon inappropriée à une épreuve d’évaluation comportant des items à réponses choisies. Par exemple, certains individus peuvent tricher alors que ... [more ▼] Il n’est pas rare de voir des étudiants répondre de façon inappropriée à une épreuve d’évaluation comportant des items à réponses choisies. Par exemple, certains individus peuvent tricher alors que d’autres peuvent tenter de se sous-classer intentionnellement à un examen. Plusieurs approches ont été développées pour faire la détection de ce type d’étudiants. À ce jour, l’approche la plus prometteuse est l’utilisation d’indice de détection de type person‐fit (Meijer et Sijtsma, 2001). L’indice de détection lz (Drasgow, Levine et Williams, 1985) est fort probablement le plus utilisé et le plus connu d’entre tous. Malheureusement, cet indice est fortement affecté par le fait que l’habileté des étudiants est estimée et non pas réelle ; ce qui peut biaiser son calcul (Molenaar et Hoijtink, 1990). Pour pallier ce problème, Snijders (2001) a proposé une correction qui permet de diminuer considérablement le biais associé à la moyenne et à la variance de l’indice lz. Dans le cadre de notre projet doctoral, nous nous inspirerons de la suggestion de Snijders (2001) pour corriger deux autres indices de détection de patrons de réponses inappropriés : l’infit mean square (u) et l’outfit mean square (w). À cette fin, nous utiliserons une approche monte carliste afin d’investiguer plus en détails l’erreur de type 1 et la puissance de ces autres indices. Nos résultats préliminaires, que nous présenterons lors de cette communication, montrent que ces autres indices corrigés semblent eux aussi plus efficaces que leur version traditionnelle sans correction. [less ▲] Detailed reference viewed: 3 (0 ULg) Intervention à la Nuit Sartre - Les biographies existentiellesCormann, Grégory ![]() Conference (2013, June 07) Detailed reference viewed: 21 (0 ULg) Procédés et enjeux de l'écriture polémique dans le dossier épistolaire anti-adoptianiste du concile de Francfort (794)Close, Florence ; Conference (2013, June 06) Nous proposons une relecture à deux voix – historico-littéraire – des pièces du dossier épistolaire de Francfort attribué à Alcuin. Nous envisagerons les stratégies littéraires et oratoires mises en ... [more ▼] Nous proposons une relecture à deux voix – historico-littéraire – des pièces du dossier épistolaire de Francfort attribué à Alcuin. Nous envisagerons les stratégies littéraires et oratoires mises en œuvres par Alcuin au nom des évêques francs, d’une part, et de Charlemagne, de l’autre, pour tenter de ramener l’épiscopat espagnol dans le giron romain. Nous tenterons d’affiner notre lecture des positions de chacun, perçues à travers le prisme des mots du diacre anglo-saxon. La confrontation de ces lettres synodales à celles qui ont été envoyées par les évêques espagnols, emmenés par l’archevêque Élipand de Tolède, devrait nous permettre de nourrir une réflexion sur le rôle, l’importance et la puissance stylistique du genre épistolaire, hérité de l’Antiquité, dans deux foyers importants de haute culture de l’époque – la péninsule ibérique et le monde insulaire – ainsi que sur l’impact de cette querelle épistolaire dans le processus de re-développement du genre dans le cadre de la renaissance carolingienne. [less ▲] Detailed reference viewed: 19 (1 ULg) Innovative Methodology for the Definition of Design Spaces of Chromatographic MethodsRozet, Eric ; ; Lebrun, Pierre et alConference (2013, June 06) As defined by ICH [1] and FDA, Quality by Design (QbD) stands for “a systematic approach to development that begins with predefined objectives and emphasizes product and process understanding and process ... [more ▼] As defined by ICH [1] and FDA, Quality by Design (QbD) stands for “a systematic approach to development that begins with predefined objectives and emphasizes product and process understanding and process control, based on sound science and quality risk management”. A risk–based QbD–compliant approach is proposed for the robust development of analytical methods. This methodology based on Design of Experiments (DoE) to study the experimental domain models the retention times at the beginning, the apex and the end of each peak corresponding to the compounds of a mixture and uses the separation criterion (S) rather than the resolution (RS) as a Critical Quality Attribute. Stepwise multiple linear regressions are used to create the models. The estimated error is propagated from the modelled responses to the separation criterion (S) using Monte Carlo simulations in order to estimate the predictive distribution of the separation criterion (S) over the whole experimental domain. This allows finding ranges of operating conditions that will guarantee a satisfactory quality of the method in its future use. These ranges define the Design Space (DS) of the method. In chromatographic terms, the chromatograms processed at operating conditions within the DS will assuredly show high quality, with well separated peaks and short run time, for instance. This Design Space can thus be defined as the subspace, necessarily encompassed in the experimental domain (i.e. the knowledge space), within which the probability for the criterion to be higher than an advisedly selected threshold is higher than a minimum quality level. Precisely, the DS is defined as “the multidimensional combination and interaction of input variables (e.g., material attributes) and process parameters that have been demonstrated to provide assurance of quality” [1]. Therefore, this DS defines a region of operating conditions that provide prediction of assurance of quality rather than only quality as obtained with traditional mean response surface optimisation strategies. For instance, in the liquid chromatography there is a great difference in e.g. predicting a resolution (RS) higher than 1.5 vs. predicting that the probability for RS to be higher than 1.5 (i.e. P(RS> 1.5)) is high. The presentation of this global methodology will be illustrated for the robust optimisation and DS definition of several liquid chromatographic methods dedicated to the separation of different mixtures: pharmaceutical formulations, API and impurities/degradation products, plant extracts, separation of enantiomers, … [less ▲] Detailed reference viewed: 7 (5 ULg) L'équilibre sagittal dans la pathologie rachidienne.RACARU, Tudor ; MARTIN, Didier ![]() Scientific conference (2013, June 05) Detailed reference viewed: 3 (0 ULg) Bandgap Measurement by Spectroscopic Ellipsometry for Strained Ge1-xSnx; ; Nieddu, Thomas et alConference (2013, June 04) Detailed reference viewed: 20 (0 ULg) Electrical Activity of Threading Dislocations and Defect Complexes in GeSn Epitaxial Layers; ; et al Conference (2013, June 04) Detailed reference viewed: 18 (0 ULg) Composition and Thickness Dependence of GeSn Growth by Chemical Vapor Deposition; ; Nieddu, Thomas et alConference (2013, June 04) Detailed reference viewed: 16 (0 ULg) Ship Manoeuvring Behaviour in Crossing Current Near-by a Lock; ; et al in VanTorre, Marc (Ed.) Third International Conference on Ship Manoeuvring in Shallow and Confined Water (2013, June 03) Ship behaviour in current is one of the classical problems in ship manoeuvrability. However, it is not yet fully investigated. The study is motivated by an assessment study on the ship navigation near by ... [more ▼] Ship behaviour in current is one of the classical problems in ship manoeuvrability. However, it is not yet fully investigated. The study is motivated by an assessment study on the ship navigation near by a river lock where relatively strong current exists. It is demonstrated how a ship behaves in the current and relatively large drift angle may happen, if the current is comparative to ship speed. In this situation, the hydrodynamic forces and moment acting on a ship is not any more at the range of lift force/moment, and therefore normal mathematical model cannot be applied. Similar situation may occur in case of rapid river stream condition, when a ship losts its power in current. At East Japan Great Earthquake happened in 2011, many ships without their power were drifting in tsunami. It is urgent matter to investigate on the ship behaviour in such situation. [less ▲] Detailed reference viewed: 6 (0 ULg) Numerical Simulation of Double Cup Extrusion Test using the Arbitrary Lagrangian Eulerian FormalismBoman, Romain ; ; Ponthot, Jean-Philippe ![]() in Proceedings of Coupled Problems 2013 (2013, June) Detailed reference viewed: 12 (4 ULg) Réaction transfusionnelle hémolytique retardée (RTHR) suite à une transfusion massive de concentrés érythrocytaires ABO-incompatiblesMONFORT, Mélanie ![]() Poster (2013, June) Detailed reference viewed: 5 (1 ULg) Over een toiletartikel: Hendrik van Veldekes 'Sente Servaes' en Camille HuysmansSteyaert, Kris ![]() in Spiegel der Letteren (2013), 55(2), 189-200 In 1858 J.H. Bormans published the first edition of Hendrik van Veldeke’s legend of Saint Servatius which had only just come to light. Nearly forty years later, Camille Huysmans supplied additional ... [more ▼] In 1858 J.H. Bormans published the first edition of Hendrik van Veldeke’s legend of Saint Servatius which had only just come to light. Nearly forty years later, Camille Huysmans supplied additional information about the work’s discovery. In a humorous letter printed in the Limburgsch jaarboek (1895-1896) he revealed how one of his former teachers, during a visit to a friend’s house, had stumbled upon the fifteenth-century manuscript in the toilet, ready to be used as toilet paper. Only recently have scholars begun to cast doubt on Huysmans’s story. A closer look at Huysmans’s student career in Liège and his involvement in the association Onze Taal (Our Language) may shed new light on the origins and veracity of his account. [less ▲] Detailed reference viewed: 34 (5 ULg) Les enjeux de la gestion de la diversitéCornet, Annie ![]() Learning material (2013) Detailed reference viewed: 11 (0 ULg) Enjeux techniques, symboliques et politiques de la mesure de la diversité dans les entreprises et les organisations?; ; Cornet, Annie ![]() in Management International = International Management = Gestión Internacional (2013) Detailed reference viewed: 17 (2 ULg) L'Année sartrienne, n° 27Cormann, Grégory ![]() Book published by Groupe d'études sartriennes (2013) Detailed reference viewed: 20 (2 ULg) Brain metabolic dysfunction in Capgras syndrome during Alzheimer’s disease: a positron emission tomography studyJedidi, Haroun ; ; et alPoster (2013, June) Detailed reference viewed: 24 (9 ULg) |
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