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See detailLe potentiel diagnostique des épreuves standardisées au Luxembourg.
Dierendonck, Christophe; Burton, Réginald; Fagnant, Annick ULg

Conference (2009, November)

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See detailPotentiel du nez électronique comme outil de détection d'évènements de suralimentation de digesteurs anaérobies
Adam, Gilles ULg

Speech (2010)

Le succès croissant des énergies renouvelables et locales provient du développement de politiques favorables aux énergies vertes dont le résultat est le développement croissant de la filière de ... [more ▼]

Le succès croissant des énergies renouvelables et locales provient du développement de politiques favorables aux énergies vertes dont le résultat est le développement croissant de la filière de méthanisation agricole en Belgique et au Grand Duché du Luxembourg. La plupart des stations de méthanisation agricole ne peuvent travailler à un rendement optimum afin d'éviter toute suralimentation des réacteurs qui conduit à une perturbation de la digestion. De plus, le monitoring du processus est réalisé par des analyses sur la phase liquide dont les délais ne permettent pas de gérer instantanément le processus de digestion. De cela apparait la nécessité d'un outil simple de suivi servant à prévenir en ligne toute perturbation du processus et de réagir rapidement. Dans cette optique, le nez électronique est un outil potentiel du suivi en ligne des réacteurs anaérobies basé sur l'analyse de la phase gazeuse. Les nez électroniques sont composés d'un réseau de capteurs à gaz non spécifiques qui peuvent répondre à différentes substances dans une matrice complexe, comme le biogaz, et produire des réponses complexes qui sont traitées par analyses multivariées et par des systèmes de reconnaissance. L'objectif de cette étude est de démontrer la capacité d'un système type nez électronique comme un outil robuste, fiable et facile à utiliser pour le suivi du processus des réacteurs anaérobies à la ferme et prévenir des situations de suralimentation des digesteurs. Un nez électronique composé de six capteurs gaz à semi-conducteurs a été testé pendant deux mois sur douze mini-digesteurs semi-continus inoculés avec de la boue anaérobie (1,5 L; 2,2% MS; 54,4% MOS). Les mini-digesteurs ont été nourris avec trois types de substrats: (i) saccharose; (ii) lipides et (iii) un mélange de lipides et saccharose en proportion 1:1. Deux stratégies d'alimentation ont été suivies: un contrôle avec un taux de charge organique de 1,33 g.L-1.jour-1 et une stratégie de suralimentation croissante évoluant de 1,33 à 5,33 g.L-1.jour-1. La concentration en méthane, dioxyde de carbone, sulfure d'hydrogène et monoxyde de carbone et le pH ont été mesurés quotidiennement sur le biogaz issu des mini-digesteurs. Les échantillons de biogaz ont ensuite été dilués 25 fois avec de l'air de référence avant d'être analysés sur le nez électronique. Les résultats de l'analyse en composantes principales des signaux des six capteurs à gaz du nez électronique démontrent que les situations de suralimentation sont détectées par le nez électronique. Les taux de charge organique élevés (> 3 g.L-1.jour-1) sont séparés des contrôles (1,3 g.L-1.jour-1). Les différents types de substrats sont également distingués dans le graphique des composantes principales mais les contrôles de chaque type de substrat sont proches et forment un zone de digestion stable (taux de charge < 3 g.L-1.jour-1) indépendante du substrat. Cela démontre le potentiel du nez électronique à prévenir des phénomènes de suralimentation des digesteurs anaérobies, indépendamment du substrat utilisé. L'intensité de la suralimentation peut-être estimée par la distance euclidienne par rapport au centre de gravité des scores des mini-digesteurs contrôles. Ces résultats devront être validés sur des réacteurs pilotes et finalement sur des installations réelles. [less ▲]

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See detailLe potentiel du saule pour la phytostabilisation des sols pollués par les éléments-traces métalliques
Evlard, Aricia ULg

Doctoral thesis (2013)

Since the ‘80s, when the concept of phytoremediation first appeared, a lot of research has been put into studying the efficiency of woody plants in metal extraction. Willows, as fast growing plants and ... [more ▼]

Since the ‘80s, when the concept of phytoremediation first appeared, a lot of research has been put into studying the efficiency of woody plants in metal extraction. Willows, as fast growing plants and because of their tolerance to difficult edaphic conditions, have been particularly well investigated. In this investigation, the essays were done on Salix clones, which come from a Walloon collection provided by ECOLIRI and ECOLIRIMED projects. The first objective was to study the potential of these local clones by considering not only their ability to extract their pollutants, but also by adding their biomass production to this parameter. We have called the study of these criteria the phenotypic approach to the tolerance of Salix clones to metals. The second added value of this investigation lies in the second objective which aims to complete these phenotypic criteria with physiological and proteomic criteria. These last criteria are often used to study the metal tolerance of plant species, but rarely for willows. The combination of these different approaches gives a expand view of metal tolerance in Salix clones studied in this investigation. As the phenotypical parameters help to answer the extraction ability challenge, the physiological and proteomic approaches give answers linked to the “health” of the willow trees when they grow in the presence of metals. Our results indicate that the clones that produced more biomass were the ones that showed the highest metal concentrations. The clones with lower biomass production showed the same tolerance as the highest producers and our results revealed that growth reduction indicates metal tolerance. Finally, after comparing our results of the metal concentrations obtained in the twigs, to results obtained during the last two decades of research papers, we have concluded that we should reconsider the use of Salix potential in phytoextraction. The first chapter of this investigation was about Salix clones exposed to metals, but, in natural conditions, their roots are colonized by fungi. Thus, their rhizosphere constitutes a separate ecosystem, which is interesting to investigate. The rhizospheric fungi, the first interface between roots and soil pollutants, play an important role in metal tolerance in woody plants. For this reason, the second chapter of this thesis aimed to test the in vitro growth of rhizospheric fungi collected on woody plant roots in the presence of cadmium. The outcome of these essays is that fungal strains have been identified and classified as tolerant to this metal. This chapter thus constitutes a first step in a future study aiming to analyze these strains in association with woody plant roots in the presence of metals. [less ▲]

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See detailPotentiel évolutif du complexe invasif Fallopia en Europe
Vanderhoeven, Sonia ULg; Saad, Layla ULg; Mahy, Grégory ULg

Scientific conference (2010, April)

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See detailLe potentiel evoque cognitif P300 (I): aspects theorique et psychobiologique.
Hansenne, Michel ULg

in Neurophysiologie Clinique = Clinical Neurophysiology (2000), 30(4), 191-210

The P300 is a positive wave which arises when an attended stimulus is detected. Its parameters depend on a number of variables, in particular the subject's mental state, the task that has to be ... [more ▼]

The P300 is a positive wave which arises when an attended stimulus is detected. Its parameters depend on a number of variables, in particular the subject's mental state, the task that has to be accomplished, the significance of the stimulus, and the degree of attention. It can be recorded with accuracy, and the different stages of information processing can therefore be analyzed. The P300 wave shows the modifications in neuronal activity which take place during the cognitive process: P300 latency provides an indirect indication of the duration of the processes involved in stimulus discrimination while its amplitude, which is influenced by a number of variables, provides an index of the intensity of the energetic activation or arousal involved. The P300 wave consists of several components which reflect distinct information-processing events (P3a, P3b, P3e, P-SR, P-CR). According to the theoretical models, it is hypothesized that P300 could either represent the adaptation of the working memory to further environmental input ('context updating'), or indicate a closing process ('context closure') in information processing. As regards the physiological aspect of P300 and its association with cortical networks, various studies have suggested that several cortical generators of P300 may co-exist: the medial temporal lobe, the temporo-parietal junction, and the medial and lateral frontal lobe. Psychopharmacological studies have shown that different neurotransmitter systems are involved in the generation and modulation of P300, namely the cholinergic, noradrenergic, dopaminergic, serotoninergic and gabaergic systems. It appears that the noradrenergic agonists increase the amplitude of P300, dopaminergic agonists may have a biphasic effect (increase/reduction), while cholinergic antagonists and gabaergic agonists reduce P300 amplitude and prolong its latency. [less ▲]

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See detailLe potentiel evoque cognitif P300 (II): variabilite interindividuelle et application clinique en psychopathologie.
Hansenne, Michel ULg

in Neurophysiologie Clinique = Clinical Neurophysiology (2000), 30(4), 211-31

The P300 wave is one of the cognitive components of the event-related potential (ERP) that is used to investigate the cognitive processes, and which can be used to study patient populations with a variety ... [more ▼]

The P300 wave is one of the cognitive components of the event-related potential (ERP) that is used to investigate the cognitive processes, and which can be used to study patient populations with a variety of psychiatric disorders. Its clinical utility has been increased by the identification of factors that contribute to the variability in its amplitude and latency. However, its value as a diagnostic index has not been entirely established. It can provide a useful recording of patients' information processing, and indicate the severity of the clinical state and its possible evolution. It can also assist in determining what therapeutic approach to adopt. In the present review, the findings in the literature concerning interindividual variation in the P300 wave are first described; several variables significantly influence the amplitude and latency of this wave, such as age, gender, intelligence and personality. Following this, the relevance of the data in the literature on the clinical applications of P300 in psychopathology is examined, including the studies undertaken to obtain an objective diagnostic index for mental disorders and also those carried out to assess the problems concerning the interpretation of information connected with the mental pathologies examined. P300-associated findings on dementia, schizophrenia, depression, alcoholism, drug addiction, anxiety disorders (panic disorder, obsessive-compulsive disorder, and post-traumatic stress syndrome) and on personality disorders (schizoid, antisocial or borderline personality disorder) have been examined in detail. [less ▲]

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See detailLe potentiel lent P300. Interet clinique dans trois pathologies mentales et neurobiologie: une revue.
Charles, G.; Hansenne, Michel ULg

in Encéphale (L') (1992), 18(3), 225-36

P300 is a late component of evoked potential which meet special relevance to the study of cognitive processes. P300 indexes categorization processes and the context updating of memory. Its latency ... [more ▼]

P300 is a late component of evoked potential which meet special relevance to the study of cognitive processes. P300 indexes categorization processes and the context updating of memory. Its latency reflects the stimulus evaluation time, and P300 amplitude is related to some psychological variables such as expectancy, attention and stimulus significance. In this review, clinical correlation between P300 components and mental diseases are reported, especially dementia, schizophrenia and depression. Delayed P300 latency has been found in Alzheimer disease and in other forms of dementia. Reduced P300 amplitude as well as altered topography has been reported in schizophrenia. In depression, reduced P300 amplitude has been related with longer reaction time. Unfortunately, the diagnosis utility of P300 seems limited. The authors also propose an overview of the actual knowledge on neurobiological findings in the generation of the P300 wave. Anatomical data point out the importance of the limbic system, more specifically, of the hippocampus and the locus coeruleus, in generating and modulating P300 wave. Data from the literature on the psychopharmacological modifications induced by cholinergic, catecholaminergic and other agents, are reviewed. Although the dopaminergic and noradrenergic systems are of some importance, these data emphasise the importance of the cholinergic system for the generation and modulation of P300 amplitude and latency. The value and interpretation of these neurobiological and clinical findings are discussed. [less ▲]

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See detailPotentiel secondary metabolite biosynthesis operons in environmental colonies of Woronischinia
Lara, Yannick ULg; Lambion, Alexandre ULg; Codd, Goeffrey A. et al

Poster (2010, September 01)

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See detailPotentiel thérapeutique du coenzyme Q10
Pincemail, Joël ULg; Defraigne, Jean-Olivier ULg

in Journal de Cardiologie [= JDC] = Tijdschrift voor Cardiologie [= TVC] (2008), 1

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See detailLe Potentiel Zeta - Possibilités d'application dans l'industrie papetière et technique de Mesure
Paquot, Michel ULg; Thonart, Philippe ULg; Flambert, C. et al

in Annales de Gembloux (1977), (83), 253-275

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See detailPotentiel zootechnique du froment d'hiver chez le poulet de chair.
Beckers, Yves ULg; Wéry, O.; Thewis, André ULg

Article for general public (2004)

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See detailPotentiels d'application de deux souches de levures vis-à-vis des maladies de conservations des pommes
Jijakli, Haissam ULg; Grevesse, cathy; Lepoivre, Philippe ULg

in 1er colloque transnational sur les luttes biologique, integree, et raisonnee, le 21,22 et 23 janvier 1998 (1998)

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See detailLes potentiels riemanniens et les formes quadratiques einsteiniennes dans le problème des deux corps
Swings, Polydore ULg

in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1926), 10

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See detailPotentiels urbains et îlots de chaleur
Cornélis, Bernard ULg; Binard, Marc ULg; Nadasdi, Istvan

in Publications de l'Association Internationale de Climatologie (1998), 10

The present contribution aims at answering in a quantitative way the question: is there a relationship between urban heat island and urban potential ? If such a relationship exits, it tries to quantify it ... [more ▼]

The present contribution aims at answering in a quantitative way the question: is there a relationship between urban heat island and urban potential ? If such a relationship exits, it tries to quantify it and to answer the following questions : - would the potential model allow the representation of the heat island phenomenon ? - If so, in which conditions ? [less ▲]

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See detailLa poterie
Tunca, Önhan ULg

in Tell Sabra (1987)

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See detailLes poudres de lait
Blecker, Christophe ULg

Conference (1996, November 28)

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See detailLes poudres de lait.
Blecker, Christophe ULg

in Etude du lait et de technologie laitière. (1997)

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