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See detailL'énonciation d'une synthèse
Badir, Sémir ULg

in Nouveaux Actes Sémiotiques (2017)

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See detailDe Barcelone à Amsterdam : l'émergence de la conservation intégrée à travers les colloques internationaux du Conseil de l'Europe et de l'ICOMOS
Houbart, Claudine ULg

Conference (2017, January 31)

En 1975, la notion de conservation intégrée est consacrée par la Charte européenne du Patrimoine architectural, adoptée par le Comité des Ministres du Conseil de l’Europe avant d’être solennellement ... [more ▼]

En 1975, la notion de conservation intégrée est consacrée par la Charte européenne du Patrimoine architectural, adoptée par le Comité des Ministres du Conseil de l’Europe avant d’être solennellement proclamée et développée au Congrès d’Amsterdam (21-25 octobre 1975). Renouvelant fondamentalement les pratiques de rénovation des centres anciens avec l’ambition de créer un dialogue entre aménageurs et conservateurs, cette approche résulte de dix années de réflexions nourries par des échanges entre experts principalement européens, initiés non seulement par le Conseil de l’Europe (Confrontations de Barcelone (1965), Bath (1966), La Haye (1967) et Avignon (1968)), mais également par l’ICOMOS, dès sa fondation en 1965 (Colloques de Cacérès (1965), Tunis (1966), Leningrad et Graz (1969), Lausanne (1973), Rothenburg et Bruges (1975)). Si un regard macroscopique révèle le rôle central joué par Piero Gazzola et Raymond Lemaire, respectivement président et secrétaire général de l’ICOMOS et auteurs, avec François Sorlin, d’une étude de synthèse préalable à la Charte européenne, cette contribution se propose d’augmenter la focale afin de révéler, à travers l’étude des actes des colloques, le rôle des réseaux d’acteurs en présence dans l’élaboration de la nouvelle politique. [less ▲]

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See detailLes semences en question ou que nous posent comme questions les semences ...
Hecquet, Corentin ULg

Learning material (2017)

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See detailAutorités publiques et signes divins sous la République romaine
Berthelet, Yann ULg

Scientific conference (2017, January 31)

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See detailReconstructing the Holocene depositional environments along the northern coast of Sfax (Tunisia): Mineralogical and sedimentological approaches
Lamourou, Ali ULg; Touir, Jamel; Fagel, Nathalie ULg

in Journal of African Earth Sciences (2017), 129C

A sedimentological and mineralogical study of sedimentary cores allows reconstructing the evolution of depositional environments along the Northern coast of Sfax (Tunisia). The aim is identifying the ... [more ▼]

A sedimentological and mineralogical study of sedimentary cores allows reconstructing the evolution of depositional environments along the Northern coast of Sfax (Tunisia). The aim is identifying the factors controlling the sedimentation from the Holocene to the Present. Three 30-m sediment cores collected by drilling at 30 meter water depth were analyzed for their color, magnetic susceptibility signal, grain size by laser diffraction, organic matter content by loss of ignition, carbonate content by calcimetry and mineralogy by X-ray diffraction on bulk powder and clay < 2 m. The three cores broadly present the same sedimentological and mineralogical features. Microscopical observations of petrographic slides allow to identifying six main sedimentary facies. Bulk mineralogical assemblages comprise clay minerals, quartz, calcite, gypsum and K-feldspars. The main change concerns the carbonate content that mimics the bioclaste abundance and dilute the detrital minerals (clay minerals, quartz and feldspars). The gypsum mainly occurs in the lower sedimentary columns (SC12 and SC9) and in the upper/middle of core SC6. The clay fraction is made of a mixture of kaolinite, illite, smectite and palygorskite with no clear variation through core depth. Both grain-size parameters and magnetic susceptibility profile indicates a sharp transition in the upper 2 to 5 m of the sedimentological columns. Coarse, sandy to gravely, sediments characterized by a low magnetic susceptibility signal are replaced by fine bioclastic-rich clayey sediments. The analysis of vertical succession of depositional facies showed a fluvial depositional environment (coastal plain) basically marked by fluvial channels and inundation plains at the bottom of all cores. Core-top sediments, however, record a littoral marine environment characterized by sand depositions rich in gastropods, lamellibranches and algæ. Depositional facies, sedimentological and mineralogical parameters are consistent with a transition from a continental, fluviatile, depositional environment, with some emersion phases marked by the gypsum precipitation to a marine littoral environment. Such evolution is consistent with a relative sea-level rise which flooded the fluvial system at the coastal plain during the Holocene, in agreement with sea-level fluctuations in southeast Tunisia during the Holocene. [less ▲]

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See detailSeasonal variations in drag coefficient over a sastrugi-covered snowfield in coastal East Antarctica
Amory, Charles ULg; Gallee, Hubert; Naaim-Bouvet, Florence et al

in Boundary-Layer Meteorology (2017)

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See detailEnonciation et modes d'existence
Dondero, Maria Giulia ULg

in Nouveaux Actes Sémiotiques (2017), 120

Cet article aborde les relations entre sémiotique et philosophie latourienne à partir de la théorie de l’énonciation, cette dernière se situant tant aux fondements du projet disciplinaire de la sémiotique ... [more ▼]

Cet article aborde les relations entre sémiotique et philosophie latourienne à partir de la théorie de l’énonciation, cette dernière se situant tant aux fondements du projet disciplinaire de la sémiotique francophone contemporaine qu’à la base de la réflexion de Bruno Latour, des années 1970 jusqu’à présent . Notre propos se déploie en deux moments : dans un premier temps, nous revenons sur l’article "Petite Philosophie de l’énonciation" (1998), et nous en suivons le développement dans l’Enquête sur les modes d’existence (2012). Dans un second temps, nous réalisons une rapide archéologie de la théorie de l’énonciation dans la sémiotique contemporaine, afin de mettre en lumière les liens entre différentes traditions sémiotiques et la théorie latourienne. Plus précisément, nous nous attachons aux propositions récentes de Jacques Fontanille et de Claudio Paolucci, en prenant également en considération les contributions d’Umberto Eco et Patrizia Violi. Il s’agit de voir comment les sémioticiens peuvent tirer profit de la théorie latourienne des modes d’existence et vice versa. [less ▲]

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See detailDEVELOPMENT OF FUNCTIONAL MICELLES FROM BIODEGRADABLE AMPHIPHILIC BLOCK COPOLYMERS FOR DRUG DELIVERY AND TUMOUR THERAPY
Gulfam, Muhammad ULg

Doctoral thesis (2017)

Drug delivery systems in the size range of ~ 10-250 nm are enabling tools for the site-specific targeting and controlled release applications. To take advantage of these capabilities, various nanocarriers ... [more ▼]

Drug delivery systems in the size range of ~ 10-250 nm are enabling tools for the site-specific targeting and controlled release applications. To take advantage of these capabilities, various nanocarriers e.g., micelles, dendrimers, liposomes, nanoparticles, nanocapsules, nanotubes, and nanogels have been designed for drug delivery. Specifically, micelle-based drug carrier systems have emerged as promising tools for site-specific delivery and controlled release applications. Despite several advantages over conventional drugs, some limitations of micelle-based drug delivery have also been reported. These drawbacks include low stability in vivo, poor penetration, modest accumulation in tumor tissues, and inadequate control over drug release. To overcome these limitations, stimuli-responsive or smart polymeric nanocarriers have been developed for drug delivery and tumour therapy, previously. The most well-known internal stimuli in cancerous regions include higher acidity associated with dysregulated metabolism in tumour tissues, elevated levels of glutathione in the cytosol and nucleus of cancer cells, and altered degradative enzymes in the lysosomes, and reactive oxygen species in the mitochondria. These intrinsic microenvironments can be exploited as internal stimuli to attain active drug release in the tumor tissues or cancer cells. Particularly, the reducing potential inside the cancer cells is considerably higher than found in the extracellular environment and bloodstream. Therefore, such varying redox potential can be exploited for tumor specific drug delivery and controlled release applications. Various types of redox-responsive micelles have been developed previously. Generally, redox responsive micelles have disulfide linkages that undergo rapid cleavage in the presence of reducing agents in the intracellular components, however, are stable at oxidizing extracellular environment. The redox-responsive disulfide bridges can be incorporated into nanocarriers by placing multiple disulfide bonds in the hydrophobic backbone or by conjugating therapeutic agents to the side chain of the polymer via a disulfide linker. Another strategy to construct redox-responsive linkages is to crosslink the polymeric nanocarriers with a disulfide crosslinker. It has been studied that polymeric micelles can dissociate, especially upon administration when they are diluted below their critical micelle concentration. The stability of polymeric micelles can be enhanced by chemical crosslinking. Various types of crosslinked micelles can be prepared subjected to the localisation of the crosslinking, e.g. shell crosslinked micelles, and core crosslinked micelles. Introducing redox-responsive bridges by disulfide crosslinker may not only provide stability to nanocarriers against dilutions during circulation, but also render them responsive to reduction conditions. Specifically, redox-responsive core-crosslinked micelles have demonstrated good stability and better ‘stealth’ properties, however, the hydrophobic cores of most of the existing core-crosslinked micelles have been based on non-degradable polymers such as polyacrylamide or polyacrylate. The non-degradable constituent of the block copolymer may cause complications in clinical applications. Therefore, reduction-responsive core-crosslinked micelles comprising entirely of biologically inert or biocompatible and biodegradable polymers would be better candidates for drug delivery and controlled release application. To overcome these limitations, micelles based on polyesters (a class of aliphatic biodegradable polymers) can used for drug delivery application. In the last few decades, various FDA approved aliphatic polyesters e.g. poly(lactic-co-glycolic acid) (PLGA), poly(ε-caprolactone), and poly(lactic acid), have been intensively studied to exploit their potential in drug, gene and protein delivery and controlled release applications. However, most of these polyesters lack functional groups which make it difficult to incorporate redox-responsive linkages to core-crosslink their micelles. To address these issues, we have synthesized functional biodegradable and biocompatible block copolymers based on mPEG-b-poly(εCL-co-αClεCL). The pendent chloro groups of the block copolymer were converted into azides using nucleophilic substitution reaction to produce mPEG-b-poly(εCL-co-αN3CL) block copolymer as a precursor of reactive polymeric micelles. The synthesized polymers were characterized by NMR, FT-IR and size exclusion chromatography (SEC). Micelles were prepared using dialysis method and methotrexate (an anticancer drug) was loaded into the hydrophobic core of the reactive micelles. Micelles were subsequently crosslinked by a redox-responsive bis-alkyne ethyl disulfide crosslinker. The size distributions and morphology of core-crosslinked micelles were assessed using dynamic light scattering (DLS) and transmission electron microscopy. The drug release studies were performed under simulated non-reducing and reducing conditions. Cellular uptake studies in human breast cancer cells (MCF7 cells) were performed using Oregon-green loaded core-crosslinked micelles. The MTX-loaded core-crosslinked micelles were assessed for their cytotoxicity in human breast cancer cells by MTT assays. The apoptosis inducing potential of MTX-loaded core-crosslinked micelles was analysed using Hoechst/PI assays and was further probed by annexin-V/PI assays. The data from these studies indicate that drug release from these cross-linked micelles can be controlled and that the redox-responsive micelles are more effective carriers for MTX than non-cross-linked analogues in the cell-lines tested. In another strategy, a multifunctional amphiphilic block copolymer based on α-amine-PEG-b-poly(εCL-co-αN3εCL) was synthesized and subsequently was used to conjugate methotrexate on the hydrophilic block for receptor mediated targeting of breast cancer cells. Cellular uptake studies revealed 2.3-fold higher uptake of MTX-conjugated micelles as compared with un-conjugated micelles. The blank micelles showed low cytotoxicities in breast cancer cells, however, MTX-conjugated micelles exhibited greater antitumor activities in contrast to free-MTX. We hypothesize that these functional micelles could be potentially powerful nanocarriers for stimuli-responsive controlled release, active tumour targeting and therapy. [less ▲]

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See detailCyanobacterial Contribution to Travertine Deposition in the Hoyoux River System, Belgium
Kleinteich, Julia; Golubic, Stjepko; Pessi, Igor S. et al

in Microbial Ecology (2017)

Travertine deposition is a landscape-forming process, usually building a series of calcareous barriers differentiating the river flow into a series of cascades and ponds. The process of carbonate ... [more ▼]

Travertine deposition is a landscape-forming process, usually building a series of calcareous barriers differentiating the river flow into a series of cascades and ponds. The process of carbonate precipitation is a complex relationship between biogenic and abiotic causative agents, involving adapted microbial assemblages but also requiring high levels of carbonate saturation, spontaneous degassing of carbon dioxide and slightly alkaline pH. We have analysed calcareous crusts and water chemistry from four sampling sites along the Hoyoux River and its Triffoy tributary (Belgium) in winter, spring, summer and autumn 2014. Different surface textures of travertine deposits correlated with particular microenvironments and were influenced by the local water flow. In all microenvironments, we have identified the cyanobacterium Phormidium incrustatum (Nägeli) Gomont as the organism primarily responsible for carbonate precipitation and travertine fabric by combining morphological analysis with molecular sequencing (16S rRNA gene and ITS, the Internal Transcribed Spacer fragments), targeting both field populations and cultures to exclude opportunistic microorganisms responding favourably to culture conditions. Several closely related cyanobacterial strains were cultured; however, only one proved identical with the sequences obtained from the field population by direct PCR. This strain was the dominant primary producer in the calcareous deposits under study and in similar streams in Europe. The dominance of one organism that had a demonstrated association with carbonate precipitation presented a valuable opportunity to study its function in construction, preservation and fossilisation potential of ambient temperature travertine deposits. These relationships were examined using scanning electron microscopy and Raman microspectroscopy. [less ▲]

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See detailDépolution des sédiments d’une mangrove de l’estuaire du Wouri : évaluation du potentiel de microflores.
Semboung Lang, Firmin ULg

Doctoral thesis (2017)

L’importance des écosystèmes de mangroves n’est plus à démontrer dans l’équilibre naturel des côtes des régions tropicales. Elles constituent un écosystème particulier et jouent un rôle important dans la ... [more ▼]

L’importance des écosystèmes de mangroves n’est plus à démontrer dans l’équilibre naturel des côtes des régions tropicales. Elles constituent un écosystème particulier et jouent un rôle important dans la production de la biomasse. Mais l’exploitation excessive du bois des palétuviers, les pollutions diverses suite à l’exploitation pétrolière et gazière, sont autant de facteurs qui contribuent à la dégradation des forêts de mangroves. Ainsi, entre 1980 et 2000, environ 35% de la superficie mondiale des mangroves a disparu. La pollution a entraîné une dégradation considérable des mangroves. Une quantité grandissante de déchets résultant des activités urbaines, industrielles et agricoles et de l’exploitation en mer du pétrole et du gaz est rejetée sans aucun traitement dans la mer et se retrouve au niveau des mangroves. Les déversements accidentels d’hydrocarbures en mer entraînent une grave pollution des mangroves et la pollution marine provenant des navires est une menace qui va sans doute s’accroître avec le développement de l’exploitation pétrolière. L’objectif de cette thèse était de mettre au point une méthode de dépollution par voie biologique des sédiments de mangroves pollués par les hydrocarbures. Il s’agissait plus précisément d’évaluer les capacités intrinsèques de dégradation de la microflore spécifique endogène, de comparer le potentiel de dégradation de cette microflore avec d’autres souches pures connues pour leur capacité à dégrader les hydrocarbures et enfin d’évaluer les différentes techniques de biodégradation adaptées pour l’élimination des hydrocarbures dans les sédiments de mangroves. Des procédés biologiques adaptés ont été mis en œuvre au cours de ce travail pour restaurer les écosystèmes de mangroves. Différentes techniques de traitements biologiques impliquant la microflore spécifique endogène ont été mises en œuvre. L’évaluation du potentiel de dégradation de cette microflore a été réalisée par rapport à trois souches pures exogènes. Les résultats obtenus ont montré que le potentiel de dégradation de la microflore spécifique est comparable à celui de Rhodococcus erythropolis lorsqu’on augmente sa concentration dans les sédiments (107 CFU.g-1 de matière sèche). La croissance de cette microflore est accélérée avec la présence des nutriments tels l’azote et le phosphore. Ce qui relève davantage le taux de dégradation des hydrocarbures. Le taux de dégradation obtenu en combinant les traitements par bioaugmentation de la microflore spécifique endogène et biostimulation (86%) nous ont amené à proposer cette méthode pour dépolluer les sédiments de mangroves. L’utilisation de la microflore spécifique endogène évite de travailler avec des souches exogènes qui nous exposent aux problèmes écologiques et éthiques liés à leur utilisation. [less ▲]

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See detailInteractions between groundwater and the cavity of an old slate mine used as lower reservoir of an UPSH (Underground Pumped Storage Hydroelectricity): A modelling approach
Bodeux, Sarah ULg; Pujades, Estanislao ULg; Orban, Philippe ULg et al

in Engineering Geology (2017), 217

In the actual evolving energy context, characterized by an increasing part of intermittent renewable sources, the development of energy storage technologies are required, such as pumped storage ... [more ▼]

In the actual evolving energy context, characterized by an increasing part of intermittent renewable sources, the development of energy storage technologies are required, such as pumped storage hydroelectricity (PSH). While new sites for conventional PSH plants are getting scarce, it is proposed to use abandoned underground mines as lower reservoirs for Underground Pumped Storage Hydroelectricity (UPSH). However, the hydrogeological consequences produced by the cyclic solicitations (continuous pumpings and injections) have been poorly investigated. Therefore, in this work, groundwater interactions with the cyclically fill and empty cavity were numerically studied considering a simplified description of a slate mine. Two pumping/injection scenarios were considered, both for a reference slate rock case and for a sensitivity analysis of variations of aquifer hydraulic conductivity value. Groundwater impacts were assessed in terms of oscillations of piezometric heads and mean drawdown around the cavity. The value of the hydraulic conductivity clearly influences the magnitude of the aquifer response. Studying interactions with the cavity highlighted that seepage into the cavity occurs over time. The volume of seeped water varies depending on the hydraulic conductivity and it could become non-negligible in the UPSH operations. These preliminary results allow finally considering first geological feasibility aspects, which could vary conversely according to the hydraulic conductivity value and to the considered groundwater impacts. [less ▲]

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See detailThe Evolution of PhD Education in Spain: A Chronological Review of Supra-national and National Actions
Aliaga Isla, Rocio ULg

in Higher Education Teaaching and Learning (2017), 7

PhD education in Spain has changed; the current conception of the PhD is different from its initial concept. PhD education policy in Spain has experienced changes in its objectives and structure. Since ... [more ▼]

PhD education in Spain has changed; the current conception of the PhD is different from its initial concept. PhD education policy in Spain has experienced changes in its objectives and structure. Since its membership into the European Community, institutional policies at supra-national and national level have shaped and conditioned such changes. Therefore, how have PhD education policies changed over a long time in Spain? To answer this question, a chronological review has been conducted under the light of institutional theory. Several legal documents enacted at supra-national level are reviewed to frame the changes of PhD education policy at a national level. Moreover, national legal documents are reviewed to follow the evolution of PhD education in Spain. This study shows that PhD education in Spain has experienced rapid changes, which are congruent to some extent with the supra-national policies that have emerged from the social and economic change in the European Union. [less ▲]

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See detailThe Bright and Dark Sides of elliptical galaxies
Biernaux, Judith ULg

Poster (2017, January 29)

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See detailFreud
Rizzo, Rémy ULg

Scientific conference (2017, January 28)

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See detailMotor assessment of children at school: Pupils’ opinion about MOBAK-1
Cloes, Marc ULg; Vandermeeren, Benjamin

Conference (2017, January 28)

School is a privileged place for evaluating children’s physical and motor competencies. Tests are often used for educational and/or research purposes. Adults collect the data but do not verify how ... [more ▼]

School is a privileged place for evaluating children’s physical and motor competencies. Tests are often used for educational and/or research purposes. Adults collect the data but do not verify how children experience these evaluations that can be perceived as difficult moments. Even if they are supposed to motivate pupils, they can decrease the self-perception and limit the participation. Several test batteries have been developed in order to measure motor development of young children (M-ABC, KTK, TGMD …). They are based on the assessment of performances. On the other hand, MOBAK-1 has been developed in order to verify if some motor competencies are mastered or not. To our knowledge, no study tried to determine how the pupils passing these tests feel about their experience. This study focused on that original topic. Seven primary school PE teachers administrated the MOBAK-1 tests to their classes (149 1st and 2d grades – 6-8 year-old). After the tests, pupils fulfilled an adapted questionnaire based on pictograms designed to facilitate pupils’ understanding. The most important finding is that 80.5% of the pupils answered that they loved doing the tests. Only 3 pupils expressed a negative opinion. As pointed out by the correlation between the real achievement mean scores and the perceived competence mean score for each test (r= 0.90), pupil’s self-assessment seemed appropriate. The correlation between the perceived competence and appraisal of the tests is lower (r=0.59). The gamelike status of some tests would be more determinant for their appraisal by the pupils than their level of achievement: balancing is definitely the most appreciated test (35.6% of the pupils selected it). In the same way, even if the achievement level is not high, throwing is relatively well appreciated. Trying to touch a target with a ball is funny. On the other hand, jumping and bouncing were ‘less’ appreciated. [less ▲]

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See detailInvolvement of PE teachers in motor testing. A pilot study with the MOBAK-1
Cloes, Marc ULg; Mouton, Alexandre ULg; Jidovtseff, Boris ULg et al

Conference (2017, January 28)

Fundamental motor patterns are prerequisites to specific motor/sports skills and a determinant of the involvement in physical activity. Several tools have been developed in order to measure motor ... [more ▼]

Fundamental motor patterns are prerequisites to specific motor/sports skills and a determinant of the involvement in physical activity. Several tools have been developed in order to measure motor development in children. Each test battery presents its own characteristics. MOBAK-1 focuses on two categories of basic motor competencies in order to record the effects of physical education (PE) at the elementary school level. That tool proposed 8 tests. For each of them, pupils receive point scores (0–2 points) according to the quality of their performance. MOBAK-1 is supposed to be used by PE teachers but there is still a lack of data about this, justifying the present study. We trained 7 PE teachers (4 males) and analysed the way they implemented the tests in their classes (1st and 2d grades – 6-8 year-old pupils). The training comprised a description of the tests with video examples of the expected movements and common errors, and an analysis of the reliability of the teachers evaluating pupils’ performances showed on video (at least 10 trials). A participating observation and a short interview were planned to analyse the evaluation process of each PE teacher. Catching and Rolling reached the reliability requirements within the first 10 trials while 15 to 16 videos were necessary for the six other tests. Two teachers seemed to have more difficulties that could be related to their lack of experience (P1) or a potential lower interest (P7). Before implementing the test with their classes, all teachers read again the guidelines. The majority was really satisfied by the information provided by the researchers (3.86/4) and confident about how to manage the evaluation (3.57/4). Five teachers worked alone and 4 were able to evaluate one class/lesson. All teachers developed specific strategies in order to save time. Several practical recommendations have been proposed. [less ▲]

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