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See detailThermal and quantum depletion of superconductivity in narrow junctions created by controlled electromigration
Baumans, Xavier ULg; Cerbu, Dorin; Adami, Obaïd-Allah ULg et al

in Nature Communications (2016), 7

Superconducting nanowires currently attract great interest due to their application in single-photon detectors and quantum-computing circuits. In this context, it is of fundamental importance to ... [more ▼]

Superconducting nanowires currently attract great interest due to their application in single-photon detectors and quantum-computing circuits. In this context, it is of fundamental importance to understand the detrimental fluctuations of the superconducting order parameter as the wire width shrinks. In this paper, we use controlled electromigration to narrow down aluminium nanoconstrictions. We demonstrate that a transition from thermally assisted phase slips to quantum phase slips takes place when the cross section becomes less than 150 nm2 . In the regime dominated by quantum phase slips the nanowire loses its capacity to carry current without dissipation, even at the lowest possible temperature. We also show that the constrictions exhibit a negative magnetoresistance at low-magnetic fields, which can be attributed to the suppression of superconductivity in the contact leads. These findings reveal perspectives of the proposed fabrication method for exploring various fascinating superconducting phenomena in atomic-size contacts. [less ▲]

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See detailPhenotypic characterization of the indigenous chickens (Gallus gallus) in the northwest of Algeria
Dalhoum, L.; Moula, Nassim ULg; Halbouche, M. et al

in Archiv für Tierzucht = Archives Animal Breeding (2016), 59

This study was conducted to characterize local chickens in the northwest of Algeria based on some phenotypic traits and to look at prediction of body weight from morphometric measurements (linear body ... [more ▼]

This study was conducted to characterize local chickens in the northwest of Algeria based on some phenotypic traits and to look at prediction of body weight from morphometric measurements (linear body). The results indicated that the predominant comb colour was dark red (77.8%), followed by light red (22.2%). Tarsus colour was either white (40.9%), grey (31%), yellow (15.39%), dark (8.05%), or green (4.51%). Most chickens (81.7%) had orange eyes, while 10.37 and 7.92% had yellow and dark-brown eyes, respectively. The dominant earlobe colour was white (73.96%), followed by red (16.81%). The remaining proportion included yellow and red-mottled yellow and black earlobes. Proportions of the adaptive genes were low. Incidences of Na, F, Pti, Cr, R, and P genes were 8.82, 0.45, 1.22, 5.54, 3.35, and 4.7%, respectively. The calculated gene frequencies ranged from 0.002 to 0.045. Variations were also found in quantitative morphological traits. Sex-associated differences (P<0.001) were observed in almost all the parameters evaluated with higher values recorded for males. Phenotypic correlations of body weight and biometric traits ranged from −0.13 to 0.88 and −0.15 to 0.97 for males and females, respectively. From the factor analysis with varimax rotation of the intercorrelated traits, three principal components which accounted for 71.6 and 73.2% of the total variance were extracted in males and females, respectively. Orthogonal body shape characters derived from the factor analysis accounted for 84.3 and 94.2% of the variation in body weight of males and females, respectively. Information obtained from this study could be useful in an appropriate management, breeding programmes for selection and utilization of Algerian chicken genetic resources. [less ▲]

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See detailQu'est-ce qu'un cycle arthurien en prose ?
Morato, Nicola ULg

Scientific conference (2016, February 16)

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See detailMise en recueil et cyclisation des textes de théâtre
Henrard, Nadine ULg

Conference (2016, February 16)

Sur la base de l'examen d'une variété de cas, cette étude s'intéresse à la manière dont se regroupent les textes de théâtre dans la tradition : rassemblement au sein des manuscrits, collections de textes ... [more ▼]

Sur la base de l'examen d'une variété de cas, cette étude s'intéresse à la manière dont se regroupent les textes de théâtre dans la tradition : rassemblement au sein des manuscrits, collections de textes, cyclisation. Les exemples s'étalent de la fin XIe au XVIe s.; ils sont puisés à des corpus variés (latin, langue d'oc ou d'oïl; théâtre religieux et théâtre profane). [less ▲]

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See detailCycle, cercle, compilation. Introduction
Henrard, Nadine ULg

Conference (2016, February 16)

Introduction à la journée "Cycle, cercle, compilation", s'intéressant à la constitution d'ensembles d'hommes (cercles littéraires) ou de textes (compilations, cycles) au Moyen Âge. Les questionnements ... [more ▼]

Introduction à la journée "Cycle, cercle, compilation", s'intéressant à la constitution d'ensembles d'hommes (cercles littéraires) ou de textes (compilations, cycles) au Moyen Âge. Les questionnements soulevés par cette journée touchent ainsi à tous les stades de la chaîne du texte, de l’écriture à la réception et nécessitent de conjuguer axes synchronique et diachronique, données codicologiques et littéraires, historiques et aussi sociologiques. Ils invitent à interroger la part du hasard et de l’intention qui joue dans le rassemblement des œuvres et montrent, si besoin en était encore, qu’il est indispensable d’inscrire le fait littéraire dans une dynamique globale, en rappelant que les œuvres ne sont que des pièces imbriquées dans divers systèmes avec lesquels elles entrent en dialogue. [less ▲]

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See detailQualité d’accueil dès l’entrée en maternelle
Pirard, Florence ULg; Morgante, Aurélie; Ajouaou, Samira

Diverse speeche and writing (2016)

Partant de la voix des parents et de résultats de recherches, il s'agit de débattre de questions clés : comment accueillir au mieux chacun des enfants et leurs familles quels que soient le parcours et la ... [more ▼]

Partant de la voix des parents et de résultats de recherches, il s'agit de débattre de questions clés : comment accueillir au mieux chacun des enfants et leurs familles quels que soient le parcours et la situation familiale ? Quelles vigilances particulières ?Quelle attention est portée au moment charnière de transition que représente l'entrée à l'école maternelle ? Comment communiquer au mieux à propos des faits et événements quotidiens qui concernent la vie de l'enfant à l'école ? Quelle place pour la documentation ? [less ▲]

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See detailBilan des 10 ans de l’Arrêté Royal sur la Planification d’urgence: Le cycle tourne-t-il rond ?
Fallon, Catherine ULg; Thiry, Aline ULg; Zwetkoff, Catherine ULg

Conference given outside the academic context (2016)

L’objectif du projet PULL mené par le Centre de recherche SPIRAL est de préévaluer l’opportunité et la faisabilité de l’application de l’approche « living lab (LL) » à la gestion du cycle du risque en ... [more ▼]

L’objectif du projet PULL mené par le Centre de recherche SPIRAL est de préévaluer l’opportunité et la faisabilité de l’application de l’approche « living lab (LL) » à la gestion du cycle du risque en Wallonie. Des interviews non directives menées dans le cadre de ce projet et la littérature scientifique relative aux Living lab dans différents domaines d’application, suggèrent en effet que la méthodologie LL pourrait s’avérer utile dans le contexte de la réforme en matière de la gestion publique des risques et des crises (crisis management and emergency planning) Nous avons organisé une enquête en ligne (de type Delphi – 24 experts associés) avec deux tours : le premier est consacré au « diagnostic » par les experts des problèmes rencontrés dans leur pratique professionnelle de l’analyse du risque et de la planification d’urgence. Le deuxième tour met en discussion les forces, faiblesses d’une démarche « Living Lab » pour améliorer les pratiques de planification d’urgence. [less ▲]

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See detailInvasive occipital nerve stimulation for refractory chronic cluster headache: what evolution at long-term? Strengths and weaknesses of the method.
MAGIS, Delphine ULg; Gerard, Pascale; Schoenen, Jean ULg

in Journal of Headache & Pain (2016)

BACKGROUND: Invasive Occipital Nerve Stimulation (iONS) is a costly technique which appears effective in drug-refractory chronic cluster headache (drCCH) management. Available data on long-term ... [more ▼]

BACKGROUND: Invasive Occipital Nerve Stimulation (iONS) is a costly technique which appears effective in drug-refractory chronic cluster headache (drCCH) management. Available data on long-term effectiveness and safety of iONS in this indication are scarce, though they could be useful to neurologists and patients in daily practice. The purpose of this short report is to discuss the very long-term outcome of a drCCH cohort, including adverse events. FINDINGS: Previously, favourable results were obtained with iONS in 15 drCCH patients: 80 % were significantly improved and 60 % were pain free. We report here the very long-term follow-up (up to nine years) of 10 patients belonging to this cohort. Meanwhile 5 patients had to be definitively explanted because of device infection (3) or paresthesia intolerance (2). Four patients (40 %) evolved to an episodic form of CH. Six remained chronic but their attack frequency was decreased by 70 % on average. Intake of preventive drugs is still necessary in 80 % of patients. All patients needed at least one battery replacement. CONCLUSIONS: Up to nine years after implantation, iONS is still effective in most patients with drCCH. Concomitant preventive drugs remain often necessary. Forty percent of patients reverse to episodic CH, possibly by natural history. iONS is not a benign procedure but device-related complications appear similar to those reported with other invasive neurostimulators. [less ▲]

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See detailRankine cycle based waste heat recovery system applied to heavy duty vehicles: topological optimization and model based control
Grelet, Vincent ULg

Doctoral thesis (2016)

standards force the original engine manufacturers to search for innovative solutions in order to reduce oil consumption. As an important part of the energy contained in the primary carrier (the fuel) is ... [more ▼]

standards force the original engine manufacturers to search for innovative solutions in order to reduce oil consumption. As an important part of the energy contained in the primary carrier (the fuel) is lost to the ambient through heat, it seems convenient to recover a part of this thermal energy and to turn it into fuel consumption reduction. Thermodynamic bottoming cycle such as the Rankine cycle could be used to meet this objective. Its popular use throughout the world for electricity generation makes it a natural candidate for on-board implementation in vehicles. However, a certain number of hurdles are still present before the system can be efficiently applied to heavy-duty trucks. In the last thirty years, numerous studies heave been carried out to evaluate the real potential of that kind of system on a vehicle but nothing has yet been commercialized. The heat sources to recover from, the constraints relative to the on-board application and the long and frequent transient behavior of the vehicle mean both the system architecture and its control strategy need to be optimized. The system optimization leads to a choice in terms of working fluid, heat sources and sinks, and components sizing in order to maximize power recovery and hence the fuel saving. The control plays a major role by using the capability of such a system to ensure an efficient and safe operation and limiting the interactions with the other vehicle sub-systems. In this thesis, a system design methodology is introduced to optimize the system architecture using complete model-based vehicle simulation. The constraints relative to the mobile application are taken into consideration to evaluate the potential of such a system. Modelbased control strategies for on controlled variable, namely the superheat level, are developed. Constrained by the implementation platform, different control frameworks ranging from PID to model predictive controllers or observer based controllers are developed to fit into a normal automotive electronic control unit. Most of these novel strategies were experimentally validated on a test rig developed during the thesis. [less ▲]

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See detailLes caractéristiques du capitalisme industriel et financier belge dans la seconde moitié du 19e siècle
Geerkens, Eric ULg

Conference given outside the academic context (2016)

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See detailNanocarriers for the treatment of glioblastoma multiforme: Current state-of-the-art
Karim, Reatul ULg; Palazzo, Claudio ULg; Evrard, Brigitte ULg et al

in Journal of Controlled Release (2016)

Glioblastoma multiforme, a grade IV glioma, is the most frequently occurring and invasive primary tumor of the central nervous system, which causes about 4% of cancer-associated-deaths, making it one of ... [more ▼]

Glioblastoma multiforme, a grade IV glioma, is the most frequently occurring and invasive primary tumor of the central nervous system, which causes about 4% of cancer-associated-deaths, making it one of the most fatal cancers. With present treatments, using state-of-theart technologies, the median survival is about 14 months and 2 year survival rate is merely 3–5%. Hence, novel therapeutic approaches are urgently necessary. However, most drug molecules are not able to cross the blood–brain barrier, which is one of the major difficulties in glioblastoma treatment. This review describes the features of blood–brain barrier, and its anatomical changes with different stages of tumor growth. Moreover, various strategies to improve brain drug delivery i.e. tight junction opening, chemical modification of the drug, efflux transporter inhibition, convection-enhanced delivery, craniotomy-based drug delivery and drug delivery nanosystems are discussed. Nanocarriers are one of the highly potential drug transport systems that have gained huge research focus over the last few decades for site specific drug delivery, including drug delivery to the brain. Properly designed nanocolloids are capable to cross the blood–brain barrier and specifically deliver the drug in the brain tumor tissue. They can carry both hydrophilic and hydrophobic drugs, protect them from degradation, release the drug for sustained period, significantly improve the plasma circulation half-life and reduce toxic effects. Among various nanocarriers, liposomes, polymeric nanoparticles and lipid nanocapsules are the most widely studied, and are discussed in this review. For each type of nanocarrier, a general discussion describing their composition, characteristics, types and various uses is followed by their specific application to glioblastoma treatment. Moreover, some of the main challenges regarding toxicity and standardized evaluation techniques are narrated in brief. [less ▲]

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See detailOne decade of active avian influenza wild bird surveillance in Belgium showed a higher viroprevalence in hunter-harvested than live-ringed birds
Steensels, Mieke; Vangeluwe, Didier; Linden, Annick ULg et al

in Avian Diseases (2016), 60(1s), 387-393

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See detailDouble thermoresponsive di- and triblock copolumers based on N-vinylcaprolactam and N-vinylpyrrolidone: synthesis, micellisation ang gelation
Mathieu, Kevin ULg; Kermagoret, Anthony; Thomassin, Jean-Michel ULg et al

Poster (2016, February 15)

The development of stimuli-responsive polymers, especially thermo-responsive ones, has been a tremendous field of research in the last years. The solubility of such macromolecules can be reversibly ... [more ▼]

The development of stimuli-responsive polymers, especially thermo-responsive ones, has been a tremendous field of research in the last years. The solubility of such macromolecules can be reversibly triggered by small changes of temperature without additives. Poly(N-vinylcaprolactam) (PNVCL), which exhibits a lower critical solution temperature (LCST) around 36°C and a low toxicity, is of particular interest especially for biomedical applications. For these reasons, the insertion of well-defined PNVCL segments in more complex architectures is highly desirable but it requires efficient synthetic tools. In this context, we have developed a cobalt-mediated radical polymerization (CMRP) for synthesizing novel well-defined NVCL-based copolymers. First, the LCST of PNVCL was tuned over a wide range of temperature by incorporation of specific amounts of N-vinylpyrrolidone (NVP) in the backbone. Then, CMRP of NVCL followed by statistical NVCL/NVP copolymerization led to diblocks having two discrete LCSTs. Finally, double. The thermal response and multistep assembly behavior of these NVCL-containing di-and triblock copolymers were studied by turbidimetry and dynamic light scattering in dilute aqueous solution (~ 1 wt%). Rheological measurements performed on more concentrated copolymer solutions (~ 15 wt%) also emphasized their ability to form thermo-reversible gels. Gelation occurred at lower concentration and stronger gels were obtained with the triblocks because a real tridimensional network formed in this case. thermoresponsive triblocks were obtained by cobalt-mediated radical coupling (CMRC) of the parent diblocks upon treatment with isoprene. [less ▲]

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See detailWerner Herzog : sur le chemin des corps
Cormann, Grégory ULg; Hamers, Jérémy ULg

Scientific conference (2016, February 15)

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See detailDynamique des flux de carbone entre l'atmosphère et des écosystèmes ouest-africains: cas des forêts et savanes sous climat soudanien au Bénin
Ago, Expédit Evariste ULg

Doctoral thesis (2016)

In West Africa as elsewhere in other parts of the world, natural and anthropogenic ecosystems are the main sources for energy, building poles and livestock fodder. They probably behave like some nets ... [more ▼]

In West Africa as elsewhere in other parts of the world, natural and anthropogenic ecosystems are the main sources for energy, building poles and livestock fodder. They probably behave like some nets carbon sinks, but there are only few studies that have focused on their carbon exchanges with the atmosphere. Preserving terrestrial ecosystems has proven essential to any emissions mitigation policy of green house gases, notably CO2. This thesis focuses on the analysis of the CO2 fluxes in three contrasting types of the ecosystem under a Sudanian climate in Benin. Specifically, it was a cultivated forest, a protected forest and a cultivated savannah. Turbulent CO2 fluxes were measured by an eddy-covariance system placed above the ecosystems. The measurements were made during variable periods of 17 months (cultivated forest), 18 months (protected forest) and 29 months (cultivated savannah). The three studied sites have been equipped by the hydro-meteorological observatory AMMA-CATCH and the national project Ouémé 2025. The CO2 fluxes data were completed by some meteorological measurements and by an inventory of dominating species the three sites. Fluxes were examined on the basis of the two main seasons imposed by the cycle of West African Monsoon. The spatial (local and regional) and temporal (hour, seasonal, annual and inter-annual) scales were considered according to the sites. Water was the main factor controlling the dynamic of the terrestrial West African ecosystems. At the daily scales, the radiation was the main driving variable of the net CO2 fluxes. Besides that radiation control, a clear relationship was observed between the net CO2 fluxes and the canopy conductance. A limited impact of saturation deficit was observed, notably during the afternoon. The soil moisture was the main factor governing the ecosystem respiration. However, no clear dependency of the ecosystem respiration on the temperature was observed at hourly scale. After long dry periods, the ecosystem respiration increased immediately in response to the first significant rains. The CO2 fluxes and the characteristics of the protected forest were always higher than those of the cultivated savannah at the daily and seasonal scales. At the annual scale, while the protected forest (Bellefoungou) and cultivated savannah (Nalohou) sequestered an average of 640 ± 50 and 232 ± 27 g C m-2, respectively considering the period of the measurements, the cultivated forest was in equilibrium with 29 ± 16 g C m-2. Overall, the three studied ecosystems were more efficient during morning and wet season than during afternoon and dry season. Finally, this study revealed that the inter-annual variability of the carbon sequestration by the cultivated savannah was mainly controlled by the ecosystem respiration variability in relation to the soil water content variation. [less ▲]

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See detailForaging wireworms are attracted to root-produced volatile aldehydes
Barsics, Fanny ULg; Delory, Benjamin M.; Delaplace, Pierre ULg et al

in Journal of Pest Science (2016)

Soil-dwelling insects are known to react to chemical cues they encounter in the rhizosphere. Whether wireworms (Coleoptera, Elateridae) use root-emitted volatile organic chemicals to localize their host ... [more ▼]

Soil-dwelling insects are known to react to chemical cues they encounter in the rhizosphere. Whether wireworms (Coleoptera, Elateridae) use root-emitted volatile organic chemicals to localize their host plant remains, however, poorly understood. Here, we aimed at identifying chemical cues released by barley roots that attract Agriotes sordidus. In a first behavioral experiment, we assessed the ability of wireworms to orient towards live barley roots, using dual-choice olfactometers suitable for belowground insects. Then, we collected the volatile organic compounds (VOC) produced by barley roots using a dynamic head-space sampling approach. VOC were quantified and identified using gas chromatography—mass spectrometry (GC–MS). The odorant blend is composed of four aldehydes, namely hexanal, (E)-hex-2-enal, (E)-non-2-enal, and (E,Z)-nona-2,6-dienal. In a second set of dual-choice bioassays, wireworms were attracted towards a synthetic blend of these four major compounds. However, the synthetic blend was not as attractive as live roots, which is partially explained by the absence of CO2, commonly known as a strong attractant for soil-dwelling insects. While CO2 indicates the presence of living material in the vicinity, we hypothesize that additional VOC inform about the plant suitability. A better understanding of these belowground signals would contribute to the development of new integrated control strategies against wireworms. [less ▲]

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See detailPrésentation de "Fleurs d'équinoxe" de Yasujiro Ozu
Tomasovic, Dick ULg

Conference given outside the academic context (2016)

Présentation du film "Fleurs d'équinoxe" de Yasujiro Ozu (1958). Analyse des thématiques de l'oeuvre et de l'art de la mise en scène du cinéaste.

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