Results 41-60 of 54449.
Bookmark and Share    
Full Text
Peer Reviewed
See detailStudy of the chemical composition of essential oils and floral waters of Cymbopogon citratus (DC.) Stapf (Poaceae) from Senegal
Diop, Serigne Mbacké; Guèye, Momar Talla; Ndiaye, Ibrahima et al

in International Journal of Biological and Chemical Sciences (in press)

This work aimed to study the chemical composition of essential oils and floral waters of Cymbopogon citratus (DC.) Stapf (Poaceae) from Senegal. The plants were collected in two different localities ... [more ▼]

This work aimed to study the chemical composition of essential oils and floral waters of Cymbopogon citratus (DC.) Stapf (Poaceae) from Senegal. The plants were collected in two different localities, Dakar and Kaolack. The extracts were obtained by steam distillation from both fresh and dried plants and analyses carried out by GC/FID and GC/MS. Oils from Dakar were dominated by geranial which represented 46.0-43.9%, neral 31.8-31.0%, myrcene 10.8-11.7% and geraniol 2.7-4.2% in the fresh and dried plants, respectively. Their floral waters contained mainly 44.6-41.4% geranial, 39.7-35.6% neral and 8.8-13.2% geraniol. The oils from Kaolack were characterized by geranial which constituted 49.5-44.5%, neral 33.3-31.2%, myrcene 7.2-9.6% and geraniol 4.3-6.1% in the fresh and dried plants, respectively. In their floral waters, it is identified 42.8-33.6% geranial, 38.4-27.6% neral and 12.5-24.5% geraniol. This original study revealed that both oils and floral waters of C. citratus from Senegal are characterized by geranial and neral whose repellent properties against mosquitoes are known. [less ▲]

Detailed reference viewed: 18 (2 ULg)
Full Text
Peer Reviewed
See detailAutomated multimodal volume registration based on supervised 3D anatomical landmark detection
Vandaele, Rémy ULg; LALLEMAND, François ULg; MARTINIVE, Philippe ULg et al

in SCITEPRESS Digital Library (in press)

We propose a new method for automatic 3D multimodal registration based on anatomical landmark detection. Landmark detectors are learned independantly in the two imaging modalities using Extremely ... [more ▼]

We propose a new method for automatic 3D multimodal registration based on anatomical landmark detection. Landmark detectors are learned independantly in the two imaging modalities using Extremely Randomized Trees and multi-resolution voxel windows. A least-squares fitting algorithm is then used for rigid registration based on the landmark positions as predicted by these detectors in the two imaging modalities. Experiments are carried out with this method on a dataset of pelvis CT and CBCT scans related to 45 patients. On this dataset, our fully automatic approach yields results very competitive with respect to a manually assisted state-of-the-art rigid registration algorithm. [less ▲]

Detailed reference viewed: 151 (33 ULg)
Full Text
See detailSTARECAPMED, des indices pour La Méditerranée
Leduc, Michèle; Abadie, Arnaud; Donnay, Annick et al

in Actes du colloque Carhamb'ar 2017 (in press)

Le projet STARECAPMED (STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystems Drifts) a pour objectif (i) d’améliorer la compréhension du ... [more ▼]

Le projet STARECAPMED (STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystems Drifts) a pour objectif (i) d’améliorer la compréhension du fonctionnement des différents écosystèmes marins côtiers présents en Méditerranée et (ii) de décrire l’influence des activités humaines sur les processus qui gouvernent ce fonctionnement. La baie de Calvi, par sa situation exceptionnelle, est un site de référence de la Directive Européenne Cadre sur l’Eau (DCE), du monitoring de l’eutrophisation et de la contamination par les éléments traces. La Station de recherches océanographiques STARESO, implantée dans la baie depuis près de 50 ans, possède un accès unique à la mer et de nombreuses facilités logistiques. Elle a développé au fil du temps une expertise scientifique reposant notamment sur l’acquisition de longues séries temporelles de données environnementales. Ensemble, Baie et Station s’intègrent en un site atelier dédié à l’évaluation de l’état de santé des écosystèmes marins côtiers de Méditerranée Nord-Occidentale. En particulier, différents indices et indicateurs y sont développés en collaboration avec de nombreux laboratoires partenaires. Ainsi, nous avons développé, d’une part, une version non destructive de l’indice PREI (Posidonia Rapid Easy Index) d’évaluation de la qualité des eaux côtières reposant sur le suivi des herbiers à Posidonia oceanica, et d’autre part, deux indices d’évaluation de l’impact des ancrages, puis testé   l’indice EBQI (Ecosystem Based Quality Index), une approche sur la diversité écologique. Les indices TEPI (Trace Element Pollution Index) et TESVI (Trace Element Spatial Variation Index) permettent d’évaluer la contamination par les éléments traces. Le BeMSI (BEnthic Methodology Simplification) est un nouvel indicateur de la qualité du milieu défini à partir de la composition des peuplements macrobenthiques des substrats meubles et plus généralement, l’indice LIMA traduit l’attrait paysager et la richesse patrimoniale du benthos méditerranéen entre 0 et –40 m. Quant à l’indice ICAR (Indice paysager CAulerpa Racemosa), il permet d’évaluer les niveaux de colonisation par l’algue invasive Caulerpa cylindracea. Enfin, une approche innovante reposant sur l’enregistrement des sons permet d’évaluer la qualité du milieu à partir d’un paysage acoustique sous-marin. En conclusion, le développement et l’application combinée de ces différents indices et indicateurs développés dans le cadre du programme pluridisciplinaire STARECAPMED fournissent une estimation globale des états du milieu côtier méditerranéen à différents niveaux d’organisation, depuis l’espèce jusqu’à l’écosystème. De plus, leur mise en œuvre dans ce même site atelier privilégié permet de les confronter, de les ajuster et de les intercalibrer pour à terme les proposer aux gestionnaires du milieu côtier. [less ▲]

Detailed reference viewed: 30 (5 ULg)
Full Text
Peer Reviewed
See detailProbabilistic Framework for the Characterization of Surfaces and Edges in Range Images, with Application to Edge Detection
Lejeune, Antoine ULg; Verly, Jacques ULg; Van Droogenbroeck, Marc ULg

in IEEE Transactions on Pattern Analysis & Machine Intelligence (in press)

We develop a powerful probabilistic framework for the local characterization of surfaces and edges in range images, which is useful in many applications of computer vision, such as filtering, edge ... [more ▼]

We develop a powerful probabilistic framework for the local characterization of surfaces and edges in range images, which is useful in many applications of computer vision, such as filtering, edge detection, feature extraction, and classification. We use the geometrical nature of the data to derive an analytic expression for the joint probability density function (pdf) for the random variables used to model the ranges of a set of pixels in a local neighborhood of an image. We decompose this joint pdf by considering independently the cases where two real world points corresponding to two neighboring pixels are locally on the same real world surface or not. In particular, we show that this joint pdf is linked to the Voigt pdf and not to the Gaussian pdf as it is assumed in some applications. We apply our framework to edge detection and develop a locally adaptive algorithm that is based on a probabilistic decision rule. We show in an objective evaluation that this new edge detector performs better than prior art edge detectors. This proves the benefits of the probabilistic characterization of the local neighborhood as a tool to improve applications that involve range images. [less ▲]

Detailed reference viewed: 34 (7 ULg)
Full Text
Peer Reviewed
See detailÉVOLUTION DE LA TENEUR EN EAU LE LONG D’UNE TOPOSEQUENCE FORESTIERE ARGILO-LIMONEUSE
Deraedt, Deborah ULg; Colinet, Gilles ULg; Degré, Aurore ULg

in Milieux Poreux et Transferts Hydriques (in press)

For the hydrological modeling of forested watersheds, the understanding of the forest hydrodynamic is essential. This study focusses on the hydrology of a Belgian forested plot with high stoniness and ... [more ▼]

For the hydrological modeling of forested watersheds, the understanding of the forest hydrodynamic is essential. This study focusses on the hydrology of a Belgian forested plot with high stoniness and steep slope. The soil water content is monitored at several positions on the toposequence and at different depth. During rain events, peak in soil water content are observed in different depth depending on the position along the toposequence. [less ▲]

Detailed reference viewed: 139 (52 ULg)
Full Text
Peer Reviewed
See detailPrediction-focused approaches: an opportunity for hydrology
Hermans, Thomas ULg

in Groundwater (in press)

Our ability to predict the evolution of complex hydrological system is fundamental. For decades, such problems have been solved by calibrating a conceptual model of the subsurface to fit data ... [more ▼]

Our ability to predict the evolution of complex hydrological system is fundamental. For decades, such problems have been solved by calibrating a conceptual model of the subsurface to fit data. Unfortunately, model calibration does not allow a realistic uncertainty quantification, whereas stochastic inversion is often computationally prohibitive. In this contribution, prediction-focused approaches (PFAs) are introduced to overcome those main shortcomings. This new paradigm focused on generating predictions directly from the data instead of generating models. A group of prior models is used to generate the data and the prediction in order to derive a direct relationship between both types of variables. The advantages, limitations and research perspectives are discussed. [less ▲]

Detailed reference viewed: 61 (10 ULg)
Full Text
Peer Reviewed
See detailVocal change patterns during a teaching day: Inter- and intra-subject variability
Remacle, Angélique ULg; Garnier, Maëva; Gerber, Silvain et al

in Journal of Voice (in press)

Objectives: To describe the mean voice changes of 22 female teachers during a typical workday, examine the inter- and intra-subject variability, and establish a typology of different voice patterns during ... [more ▼]

Objectives: To describe the mean voice changes of 22 female teachers during a typical workday, examine the inter- and intra-subject variability, and establish a typology of different voice patterns during the workday. Methods: For each participant, fundamental frequency (F0), harmonics-to-noise ratio (HNR), jitter, and shimmer were measured on sustained vowels at the beginning and at the end of the workday, at three different times during the school year. Results: The group mean pattern showed significant increases in F0 and HNR during the workday and significant decreases in jitter and shimmer. However, considerable inter- and intra-subject variability was observed. Based on the variation in the acoustic parameters during the workday, three different voice patterns were identified. The first is characterized by a greater F0 increase during the day, interpreted as a common, appropriate adaptation to vocal load. The second is characterized by a greater increase in HNR during the day and greater decreases in jitter and shimmer, interpreted as hyperfunctional voice production. The third is characterized by greater decreases in F0 and HNR and greater increases in jitter and shimmer, suggesting acute inflammation or muscle fatigue following the workday. Conclusions: The observed variety of vocal patterns during the workday emphasizes the need to study this phenomenon individually and target different types of behaviors in order to develop tailored prevention and treatment methods. [less ▲]

Detailed reference viewed: 61 (4 ULg)
Full Text
Peer Reviewed
See detailEpistémologie de la théorie du complot
Jamin, Jérôme ULg

in Cahiers de l'Éducation Permanente (Les) (in press)

Detailed reference viewed: 76 (13 ULg)
Full Text
Peer Reviewed
See detailLe populisme aux Etats-Unis
Jamin, Jérôme ULg

in Revue de la Faculté de Droit de l'Université de Liège (in press)

Detailed reference viewed: 80 (15 ULg)
Full Text
Peer Reviewed
See detailLe phénotype d’Akhenaton ; revue critique entre canons artistiques et expression pathologique.
JEDIDI, Zayd ULg; JEDIDI, Haroun ULg; LAVEAUX, Elisabeth ULg et al

in Revue Médicale de Liège (in press)

Of all the royal families of ancient or modern fame, few are as iconic as the eighteenth dynasty of pharaohs of the New Kingdom of Egypt, whose opulence and deeds we are still familiar to nearly 3,500 ... [more ▼]

Of all the royal families of ancient or modern fame, few are as iconic as the eighteenth dynasty of pharaohs of the New Kingdom of Egypt, whose opulence and deeds we are still familiar to nearly 3,500 years after their time. Tenth pharaoh of this dynasty and father of Tutankhamun, Akhenaten (Amenhotep/Amenhotep IV) still fascinates Egyptologists and history lovers through the many questions surrounding his atypical rule. One of the most striking aspects of the so-called Amarna period concerns the representations of the pharaoh himself, very confusing compared to the traditional iconography of the New Kingdom. These intriguing portraits of Pharaoh raised a whole lot of medical assumptions, more or less substantiated. We review here the main theories developed throughout history. [less ▲]

Detailed reference viewed: 197 (53 ULg)
Full Text
Peer Reviewed
See detailDesigning an air-to-air heat exchanger dedicated to single room ventilation with heat recovery
Gendebien, Samuel ULg; Martens, Jonathan; Prieels, Luc et al

in Building Simulation: An International Journal (in press)

The present paper focuses on the development steps of heat exchangers dedicated to single room ventilation unit with heat recovery (SRVHR) by proposing a numerical approach. A methodology is suggested in ... [more ▼]

The present paper focuses on the development steps of heat exchangers dedicated to single room ventilation unit with heat recovery (SRVHR) by proposing a numerical approach. A methodology is suggested in order to determine the best trade-off between hydraulic and thermal performance given a specific geometry. The methodology consists in a mapping of the coefficient of performance (COP) of the unit. The latter is defined as the ratio between recovered heat and the fan energy use, given a specific indoor/outdoor temperature difference. However, the energy performance should not be the only criterion to be taken into account in the frame of the design steps of a heat recovery exchanger: technical, economic and acoustic aspects should also be considered. This numerical methodology is illustrated by means of a real example of a newly developed heat exchanger dedicated to a SRVHR. The optimization is first performed while using a semi-empirical model (based on the use of correlations and on a spatial division of the studied heat exchanger). The semi-empirical model allows for the creation of a COP map in order to identify the most effective geometry parameters for the heat exchanger. The decision concerning the final geometry is made accounting for the so-called technical, economic and acoustic considerations. A discussion on some parameters needed for the COP establishment is also proposed. [less ▲]

Detailed reference viewed: 47 (9 ULg)
Full Text
Peer Reviewed
See detailCommon Clays of Foumban area (West Cameroon): Variability, Distribution, Characterization and Potential Applications
Nkalih Mefire, Abiba ULg

in Journal of African Earth Sciences (in press)

Common clay deposits from five localities in Foumban (West Cameroon) were investigated for their morphological, mineralogical and geochemical properties to determine their potential source rocks and ... [more ▼]

Common clay deposits from five localities in Foumban (West Cameroon) were investigated for their morphological, mineralogical and geochemical properties to determine their potential source rocks and suitability in ceramic product. The analytical results were obtained by X-ray diffraction, X-ray fluorescence spectrometry, Thermogravimetric Analysis, Scanning Electron Microscopy, and Fourier Transform Infrared Spectrometry. Morphologically, an homogeneous clayey layer was found in the upper part of a laterite cover on interfluves, and a clayey heterogeneous hydromorphic material in valleys. They are minerallogically composed of kaolinite (25-84%), illite (0-18%), smectite (0- 31%), and chlorite (0-8 %), associated with quartz (2-44 %), K-feldspars (0-27 %.), plagioclase (0-26%), goethite; (0-9%) with traces of rutile and hematite (≤5 %). The geochemical analysis shows a 115 relative large amount of SiO2 (45-71%), Al2O3 (14-31%), and low Fe2O3 (up to 11 %) suggesting weathering of mainly granitic and rhyolitic parent rocks. Most studied clays could be applied to building ceramic product such as bricks (refractory or not) and tiles. Illite may promote the glassy phase responsible for the densification of the final product. In addition, the relatively high proportion of alkali elements (K2O + Na2O, 6-8%) in some samples from Marom, Koutaba and is responsible for low firing temperature. However the presence of smectite (up to 5 %) limits the application of some Koutaba and Marom clays for ceramic building. The high Fe2O3 contents (> 8 %) in some Bangourain clays implied some pretreatment. [less ▲]

Detailed reference viewed: 25 (2 ULg)
Full Text
See detailNow we're free. De lichtheid van Leonard Cohen in You want it darker (2016)
Mus, Francis ULg

in Passage, tijdschrift voor Europese literatuur en cultuur (in press)

Detailed reference viewed: 6 (0 ULg)
Full Text
See detailCarte géologique de Wallonie à l'échelle 1:25 000. Tongres-Heerderen n°34/5-6
Mottequin, Bernard ULg; Marion, Jean-Marc ULg

Cartographic material (in press)

New version of the geological map of the sheet Tongeren-Herderen (no. 107) previously published at the scale of 1/40000 by Van den Broeck (1903)

Detailed reference viewed: 159 (37 ULg)
Full Text
See detailCarte géologique de Wallonie à l'échelle 1:25 000. Notice explicative. Tongres - Heerderen n°34/5-6
Mottequin, Bernard ULg; Marion, Jean-Marc ULg

Book published by SPW/DGARNE - Révision et 2ème édition (in press)

New version of the geological map of the sheet Tongeren-Herderen (no. 107) previously published at the scale of 1/40000 by Van den Broeck (1903). First edition of the leaflet

Detailed reference viewed: 95 (28 ULg)
Full Text
Peer Reviewed
See detailProbabilistic Reliability Management Approach and Criteria for Power System Short-term Operational Planning
Karangelos, Efthymios ULg; Wehenkel, Louis ULg

in Probabilistic Reliability Management Approach and Criteria for Power System Short-term Operational Planning (in press)

This paper develops a probabilistic decision making framework for reliability management in the short-term operational planning context. We build upon our recent work, which proposed a probabilistic ... [more ▼]

This paper develops a probabilistic decision making framework for reliability management in the short-term operational planning context. We build upon our recent work, which proposed a probabilistic reliability management approach and criterion (RMAC) for the latest decision making opportunity of real-time system operation. Here, we transpose the RMAC to the preceding problem instance of short-term operational planning, wherein i) risk is aggravated by the uncertainty on power injections and weather conditions, and, ii) the problem scope concerns choosing `strategic' actions (e.g., starting additional generating units, granting outage requests for maintenance, etc.) to facilitate decision making during the forthcoming real-time system operation. To anticipate on the latter, we formalize the notion of a real-time `proxy' as a simplified model of the real-time decision making context, adequately accurate for the purpose of operational planning decision making. Stating a first proposal for such a proxy, we mathematically formulate the RMAC for short-term operational planning as a multi-stage stochastic decision making problem and demonstrate its main features by case studies on a modified version of the single area IEEE RTS-96 system. [less ▲]

Detailed reference viewed: 44 (4 ULg)
Full Text
Peer Reviewed
See detailExozodiacal clouds: Hot and warm dust around main sequence stars
Kral, Quentin; Krivov, Alexander V.; Defrere, Denis ULg et al

in Astronomical Review (in press)

A warm/hot dust component (at temperature $>$ 300K) has been detected around $\sim$ 20% of stars. This component is called "exozodiacal dust" as it presents similarities with the zodiacal dust detected in ... [more ▼]

A warm/hot dust component (at temperature $>$ 300K) has been detected around $\sim$ 20% of stars. This component is called "exozodiacal dust" as it presents similarities with the zodiacal dust detected in our Solar System, even though its physical properties and spatial distribution can be significantly different. Understanding the origin and evolution of this dust is of crucial importance, not only because its presence could hamper future detections of Earth-like planets in their habitable zones, but also because it can provide invaluable information about the inner regions of planetary systems. In this review, we present a detailed overview of the observational techniques used in the detection and characterisation of exozodiacal dust clouds ("exozodis") and the results they have yielded so far, in particular regarding the incidence rate of exozodis as a function of crucial parameters such as stellar type and age, or the presence of an outer cold debris disc. We also present the important constraints that have been obtained, on dust size distribution and spatial location, by using state-of-the-art radiation transfer models on some of these systems. Finally, we investigate the crucial issue of how to explain the presence of exozodiacal dust around so many stars (regardless of their ages) despite the fact that such dust so close to its host star should disappear rapidly due to the coupled effect of collisions and stellar radiation pressure. Several potential mechanisms have been proposed to solve this paradox and are reviewed in detail in this paper. The review finishes by presenting the future of this growing field. [less ▲]

Detailed reference viewed: 14 (0 ULg)
Full Text
Peer Reviewed
See detailKIAA1199: a novel regulator of MEK/ERK-induced Schwann cell dedifferentiation
Boerboom, Angelique; Reusch, Céline ULg; Pieltain, Alexandra ULg et al

in Glia (in press)

Detailed reference viewed: 25 (4 ULg)