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See detailRecherches de lignées aromatiques d’Abies par hybridation somatique
Fauconnier, Marie-Laure ULg; Druart, Philippe

Report (2015)

L’objectif du projet de recherche est d’associer les caractéristiques de croissance d’A. nordmanniana aux propriétés aromatiques d’autres espèces d’Abies en suivant la voie de la fusion somatique. Les ... [more ▼]

L’objectif du projet de recherche est d’associer les caractéristiques de croissance d’A. nordmanniana aux propriétés aromatiques d’autres espèces d’Abies en suivant la voie de la fusion somatique. Les travaux de recherche en culture "in vitro" sont menés au laboratoire de l’Unité de Génie biologique du Département "Science du Vivant" du CRAW (section 1) tandis que les analyses relatives à la détermination des profils aromatiques sont réalisées dans le laboratoire de l'Unité chimie générale et organique de l'Université de Liège-Gembloux Agro- Bio-Tech (section 2). Les deux Unités de recherche ont poursuivi leurs activités en parfaite collaboration. La première a tenté de restituer ou garder les propriétés embryogènes au travers de protoplastes provenant de lignées embryogènes d’A. nordmanniana, d’induire l’embryogenèse somatique sur des tissus d’embryons zygotiques d’autres Abies aromatiques et de réaliser des fusions somatiques en associant des protoplastes à des cellules de têtes d’embryons. La seconde s’occupait de caractériser les composés aromatiques, de suivre leur évolution selon période de végétation, de distinguer les espèces entre elles selon le profil aromatique de leurs graines tandis qu’en parallèle, elle mettait au point les techniques d’analyses en conditions aseptiques sur des lignées embryogènes d’A. nordmanniana d’origines génétiques différentes et sur les masses issues de fusions potentielles intra ou interspécifiques avec A. balsamea. [less ▲]

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See detailExploitation optimale des lignes électriques aériennes à haute tension par évaluation en temps réel de la flèche des conducteurs et du vent agissant sur la portée
Godard, Bertrand ULg

Doctoral thesis (2015)

[Abstract] The primary concern with the electrical loading of high-voltage overhead lines is ground clearance, which depends on several factors, including constantly varying weather parameters. Sagging of ... [more ▼]

[Abstract] The primary concern with the electrical loading of high-voltage overhead lines is ground clearance, which depends on several factors, including constantly varying weather parameters. Sagging of the conductor, the main safety criteria, is due to (thermal) expansion of the line, a complex function of air temperature, solar radiation, local wind and actual current. A patented (patent US 8184015B2) method (based on a smart sensor named AmpacimonTM attached directly to an overhead line conductor) to directly measure the sag of overhead transmission line conductors is described. The main advantage of the concept is the real time direct measurement of the sag needed for the operation of the transmission or distribution system without the need for any additional and intermediate data, such as for example load, topological data, conductor tension, conductor temperature, and ambient weather conditions. The sag is determined by analyzing the conductor's vibrations, detecting the span's frequencies of vibrations. The fundamental frequencies form the exact signature of the span. Exterior conditions such as load, weather, topology, suspension movement, creep and the presence of snow and ice affect the sag, and, therefore, are automatically incorporated into the frequency of vibrations. Thus, this method is a direct sag evaluator compared to other methods that determine the sag based on conductor temperature or conductor tension measurements and inferences about other parameters (mass of conductor, span length,…). Moreover, sensor and method does not need to be calibrated, as the sag is deduced from the detected frequencies and not from signal amplitude. Completed field tests have confirmed that the method (and sensor) gives appropriate and highly accurate sag measurements (less than a 20 [cm] margin of error). The wind speed has a dramatic impact on power line ampacity as it is the main variable responsible for cooling down the conductor, and hence for the sag value. However, a single-spot measurement does not allow knowing the global effect of the wind over the whole span, in particular for low wind speeds (typically for wind speeds whose component perpendicularly to the conductor axis lower than 2-3 [m/s]) which are dramatic for ampacity (ampere capacity) determination. A patented (patent WO 2014090416 A1) direct method (based on a smart sensor named AmpacimonTM attached directly to an overhead line conductor) for measuring a perpendicular wind speed component with respect to a suspended cable span is presented. Appropriate data analysis coupling conductor's motion frequency detection, Strouhal equation and swing angle measurement gives a full picture of any wind speed. As the cable moves as a whole, the presented method provides a value which is representative of the mean perpendicular wind speed effect along the entire suspended cable span. In the past, the difficulty of predicting weather parameters and sag has resulted in conservative assumptions to ensure public safety and power-system security. If transmission system operators are to increase the use of the overhead line circuits' load-transfer capacity while ensuring the regulatory clearances above ground are maintained, they need a system that determines the available real-time load-transfer capacity, conductor sag (and perpendicular wind speed) by direct measurement, without the need to factor in unreliable parameters. The methods and system presented in this work will open new insights to power system network management in many aspects, from congestion management to preventive maintenance. [less ▲]

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See detailDescription du manuscrit
Bauden, Frédéric ULg

in Le Journal d'Antoine Galland (1646-1715). La période parisienne. Vol. IV (1714-1715) (2015)

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See detailInvolvement of the Distinctiveness Heuristic in Children's Decision Making
Geurten, Marie ULg; Willems, Sylvie ULg; Meulemans, Thierry ULg

in International Convention of Psychological Science: ICPS, Amsterdam 2015 (2015)

Over the past decades, researchers studying adult metacognition have placed a heavy emphasis on how expectations and naïve theories about memory functioning can improve memory accuracy through the ... [more ▼]

Over the past decades, researchers studying adult metacognition have placed a heavy emphasis on how expectations and naïve theories about memory functioning can improve memory accuracy through the implementation of some metacognitive rules. By contrasts, however, research on metacognition in children has only recently started to pay attention to the influence of these heuristic-based judgments on decision making. Generally, the results of these studies indicate that memory decisions are already based on some heuristics by the ages of 7-8 years. Thus far, the question of whether younger children can do the same has widely gone unexamined. The present experiment investigates whether young children are able to reduce their false recognitions rate after distinctive encoding through the implementation of a strategic metacognitive rule. Specifically, we examine the use of a retrieval strategy called the distinctiveness heuristic whereby people infer that an event has not occurred when they cannot remember expected memorial information about it. Seventy-two children, aged 4, 6, and 9 years, studied two lists of unrelated items. One of these lists was visually displayed (picture/dictinctive condition) while the other was presented auditorily (word/no-distinctive condition). After each study phase, participants completed recognition tests. Finally, they answered questions about their explicit knowledge of the distinctive-encoding effect. The results revealed that even the youngest children in our sample showed a smaller proportion of intrusions in the picture condition than in the word condition. Furthermore, the findings of the signal detection analyses are consistent with the hypothesis that the lower rate of false recognitions after picture encoding results from the implementation of a conservative response criterion based on the participants’ metacognitive expectations (distinctiveness heuristic). Moreover, the absence of correlation between children’s explicit knowledge of the distinctiveness rule and their effective use of this metacognitive heuristic seems to indicate that its involvement in memory decisions could be mediated by implicit mechanisms. [less ▲]

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See detailLe code de droit économique: principales innovations
Thirion, Nicolas ULg

Book published by Larcier (2015)

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See detailIntroduction: Deux années de la vie d'Antoine Galland (1712-1713)
Bauden, Frédéric ULg

in Le Journal d'Antoine Galland (1646-1715). La période parisienne. Vol. III (1712-1713) (2015)

Detailed reference viewed: 3 (0 ULg)
See detailDescription du manuscrit
Bauden, Frédéric ULg

in Le Journal d'Antoine Galland (1646-1715). La période parisienne. Vol. III (1712-1713) (2015)

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See detailAtmospheric Pressure Plasma as an Activation Step for Improving Protein Adsorption on Hydroxyapatite Powder
Ozhukil Kollath, Vinayaraj ULg; Put, Sofie; Mullens, Steven et al

in Plasma Processes and Polymers (2015)

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See detailTopology on new sequence spaces defined with wavelet leaders
Bastin, Françoise ULg; Esser, Céline ULg; Simons, Laurent ULg

E-print/Working paper (2015)

Using wavelet leaders instead of wavelet coefficients, new sequence spaces of type Sν are defined and endowed with a natural topology. Some classical topological properties are then studied; in particular ... [more ▼]

Using wavelet leaders instead of wavelet coefficients, new sequence spaces of type Sν are defined and endowed with a natural topology. Some classical topological properties are then studied; in particular, a generic result about the asymptotic repartition of the wavelet leaders of a sequence in Lν is obtained. Eventually, comparisons and links with Oscillation spaces are also presented as well as with Sν spaces. [less ▲]

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See detailEffects of 2,4-dichlorophenoxyacetic acid combined to 6-Benzylaminopurine on callus induction, total phenolic and ascorbic acid production, and antioxidant activities in leaf tissue cultures of Crataegus azarolus L. var. aronia
Chaabani, Ghaya; Tabart, Jessica; Kevers, Claire ULg et al

in Acta Physiologiae Plantarum (2015), 37

The present research work describes the effects of 2,4-dichlorophenoxyacetic acid (2,4-D)/6-Benzylamino-purine (BAP) ratio on callus induction, total phenols and ascorbic acid production and antioxidant ... [more ▼]

The present research work describes the effects of 2,4-dichlorophenoxyacetic acid (2,4-D)/6-Benzylamino-purine (BAP) ratio on callus induction, total phenols and ascorbic acid production and antioxidant activities in leaf-derived calli of Crataegus azarolus (hawthorn). The supplementation of 1.0 mg/L 2,4-D and 1.0 mg/L BAP to MS medium was found to be the most efficient for callus induction (as percentage and fresh weigh). The results of biochemical analysis showed that the highest total phenols contents were obtained in callus cultured on MS medium supplemented with 2.0 mg/L 2,4-D and 1.0 mg/L BAP (52 ± 0.56 mg GAE/g DM) and were significantly lower than those of intact leaves (76 ± 1.72 mg GAE/g DM). However, the highest ascorbic acid contents were found in callus cultured on MS supplemented with 1.0 mg/L 2,4-D and 0.5 mg/L BAP (0.96 ± 0.13 mg AAE/g DM) and these amounts were statistically similar to those found in leaves tissues (0.74 ± 0.07 mg AAE/g DM). Antioxidant activities of callus extracts were determined using two TEAC assays and results showed that extract of callus cultured on MS medium supplemented with 2.0 mg/L 2,4-D and 1.0 mg/L BAP have the greatest antiradical activities against DPPH (124 ± 2.92 mg TE/g DM) and ABTS (0.19 ± 0.02 mg TE/g DM) compared to the leaves of field-grown plant. Thus, the use of high level of 2,4-D over BAP can be suitable to enhance the quality more than the quantity of bioactive compounds in leaf callus culture of hawthorn. [less ▲]

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See detailLe Code de droit économique: présentation générale
Thirion, Nicolas ULg

in Thirion, Nicolas (Ed.) Le Code de droit économique: principales innovations (2015)

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See detailInternational assessment of future low flow regimes and their impact on three water related sectors in the Meuse basin – a collaborative approach
Bauwens, Alexandra; Degré, Aurore ULg; Deraedt, Deborah ULg et al

in International Journal of River Basin Management (2015), 13(1), 123-135

There is a wide recognition of the watershed scale as the right scale for global water management, notably in the context of the WFD. Hence, it often refers to international management and therefore to ... [more ▼]

There is a wide recognition of the watershed scale as the right scale for global water management, notably in the context of the WFD. Hence, it often refers to international management and therefore to various pre-existing regional management tools, models or even objectives. In this study we aim at describing the collaborative assessment of climate change’s effect on low flow regime and the consequences on three water related sectors: drinking water production, agriculture and electricity production. The paper highlights the choices that were made during the study that involved scientific teams, managers and stakeholders from the four main countries of the Meuse Basin. It shows that the methodological choices were operational and aimed at preserving existing methods and knowledge within each country. They led to hydrological scenarios comparable to the main available ensemble approaches and to methodologies well accepted within the concerned countries. The results of the project highlight and quantify the water scarcity that the three sectors will have to face by the end of the century mainly regarding the electricity production. They also show that common allocation rules are necessary to manage water demand during future low flow periods. [less ▲]

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See detailTechnical Note: Large overestimation of pCO2 calculated from pH and alkalinity in acidic, organic-rich freshwaters
Abril, G; Bouillon, S; Darchambeau, François ULg et al

in Biogeosciences (2015), 12(1), 67-78

Inland waters have been recognized as a significant source of carbon dioxide (CO2) to the atmosphere at the global scale. Fluxes of CO2 between aquatic systems and the atmosphere are calculated from the ... [more ▼]

Inland waters have been recognized as a significant source of carbon dioxide (CO2) to the atmosphere at the global scale. Fluxes of CO2 between aquatic systems and the atmosphere are calculated from the gas transfer velocity and the water–air gradient of the partial pressure of CO2 (pCO2). Currently, direct measurements of water pCO2 remain scarce in freshwaters, and most published pCO2 data are calculated from temperature, pH and total alkalinity (TA). Here, we compare calculated (pH and TA) and measured (equilibrator and headspace) water pCO2 in a large array of temperate and tropical freshwaters. The 761 data points cover a wide range of values for TA (0 to 14 200 μmol L􀀀1), pH (3.94 to 9.17), measured pCO2 (36 to 23 000 ppmv), and dissolved organic carbon (DOC) (29 to 3970 μmol L􀀀1). Calculated pCO2 were >10% higher than measured pCO2 in 60% of the samples (with a median overestimation of calculated pCO2 compared to measured pCO2 of 2560 ppmv) and were >100% higher in the 25% most organic-rich and acidic samples (with a median overestimation of 9080 ppmv). We suggest these large overestimations of calculated pCO2 with respect to measured pCO2 are due to the combination of two cumulative effects: (1) a more significant contribution of organic acids anions to TA in waters with low carbonate alkalinity and high DOC concentrations; (2) a lower buffering capacity of the carbonate system at low pH, which increases the sensitivity of calculated pCO2 to TA in acidic and organicrich waters. No empirical relationship could be derived from our data set in order to correct calculated pCO2 for this bias. Owing to the widespread distribution of acidic, organic-rich freshwaters, we conclude that regional and global estimates of CO2 outgassing from freshwaters based on pH and TA data only are most likely overestimated, although the magnitude of the overestimation needs further quantitative analysis. Direct measurements of pCO2 are recommended in inland waters in general, and in particular in acidic, poorly buffered freshwaters [less ▲]

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See detailCOST Action FA1407: Empowering NGS technologies for the study and diagnostic of plant viruses
Olmos, Antonio; Boonham, Neil; Büttner, Carmen et al

Poster (2015)

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See detailIntroduction
Fallon, Catherine ULg

in Albarello, Luc; Fallon, Catherine; Van Haeperen, Beatrice (Eds.) Evaluation des politiques publiques (2015)

Ce livre s’adresse à toutes les personnes qui a des titres divers sont concernés par l’évaluation des politiques publiques parce qu’ils doivent en assurer la réalisation ou en encadrer la démarche. Les ... [more ▼]

Ce livre s’adresse à toutes les personnes qui a des titres divers sont concernés par l’évaluation des politiques publiques parce qu’ils doivent en assurer la réalisation ou en encadrer la démarche. Les exemples et les angles de discussion sont les plus larges possibles pour que le lecteur puisse s’approprier les outils quel que soit son secteur de responsabilité et quel que soit son territoire. Il trouvera dans la suite des chapitres non pas un livre de recettes – ce qui nous semble contraire à la logique d’évaluation de politiques – mais des cadres de réflexion, des propositions de pratiques, ainsi que des références complémentaires pour développer ses pratiques tout en mobilisant un regard critique. [less ▲]

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