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See detailLe ralentissement de la traduction et ses conséquences
Mus, Francis ULg

Conference (2009, May 20)

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See detailEvaluation of two protein extraction protocols for Pichia anomala proteome analysis.
Bajji, Mohammed; Delaplace, Pierre ULg; Mauro, Sergio et al

Poster (2009, May 19)

Pichia anomala (strain Kh6) was isolated from the surface of apple fruits and selected for its high and reliable biocontrol activity against Botrytis cinerea and Penicillium expansum. Its main modes of ... [more ▼]

Pichia anomala (strain Kh6) was isolated from the surface of apple fruits and selected for its high and reliable biocontrol activity against Botrytis cinerea and Penicillium expansum. Its main modes of action have until now been studied using essentially microbiological and molecular approaches. The study continues now using the proteomic approach and considering the in situ P. anomala/B. cinerea/apple interaction. Two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) is one of the most powerful tools used for proteomic analysis. It combines two sequential separation steps, the first dimension via isoelectric focusing (IEF) and the second one by SDS PAGE. Although recent advances in 2-D PAGE, the extraction of the whole proteome and the removal of interfering contaminants still limit its application. Sample preparation constitutes indeed a critical influential step for IEF which in turn affects 2-D gel quality. The objective of the present work was thus to develop an effective protein extraction protocol designed for 2-D PAGE analysis of the proteome of P. anomala strain Kh6. As a starting point, two contrasting protein extraction protocols were chosen to be evaluated in terms of protein yield and one-dimensional (1-D) SDS PAGE and 2-D PAGE gel patterns. The first protocol uses a urea/thiourea-based lysis buffer whereas the second protocol utilizes a hot SDS-based lysis buffer with an additional precipitation step. The comparison model used consisted of apples treated with strain Kh6 alone (K) and apples first treated with Kh6 and then inoculated with B. cinerea conidia (KB). Growth kinetics of strain Kh6 on wounded apples was determined and found to be not affected by the presence of B. cinerea conidia. Proteins were extracted from yeast pellets collected at both the exponential and stationary phases of strain Kh6 growth on apples. The evaluation of both extraction protocols indicates that more proteins were extracted with the SDS protocol and, according to 1-D assays, higher molecular weight proteins were obtained with the ‘urea/thiourea’ protocol and, regardless of the protocol used, more bands were obtained during the exponential phase. 2-D assays are currently underway and the corresponding results will be presented. [less ▲]

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See detailInfluence function of the error rate of classification based on clustering
Ruwet, Christel ULg; Haesbroeck, Gentiane ULg

Conference (2009, May 19)

Cluster analysis may be performed when one wishes to group similar objects into a given number of clusters. Several algorithms are available in order to construct these clusters. In this talk, focus will ... [more ▼]

Cluster analysis may be performed when one wishes to group similar objects into a given number of clusters. Several algorithms are available in order to construct these clusters. In this talk, focus will be on two particular cases of the generalized k-means algorithm : the classical k-means procedure as well as the k-medoids algorithm, while the data of interest are assumed to come from an underlying population consisting of a mixture of two groups. Among the outputs of these clustering techniques, a classification rule is provided in order to classify the objects into one of the clusters. When classification is the main objective of the statistical analysis, performance is often measured by means of an error rate. Two types of error rates can be computed: a theoretical one and a more empirical one. The first one can be written as ER(F, Fm) where F is the distribution of the training sample used to set up the classification rule and Fm (model distribution) is the distribution under which the quality of the rule is assessed (via a test sample). The empirical error rate corresponds to ER(F, F), meaning that the classification rule is tested on the same sample as the one used to set up the rule. This talk will present the results concerning the theoretical error rate. In case there are some outliers in the data, the classification rule may be corrupted. Even if it is evaluated at the model distribution, the theoretical error rate may then be contaminated. To measure the robustness of classification based on clustering, influence functions have been computed. Similar results as those derived by Croux et al (2008) and Croux et al (2008) in discriminant analysis were observed. More specifically, under optimality (which happens when the model distribution is FN = 0.5 N(μ1, σ) + 0.5 N(μ2, σ), Qiu and Tamhane 2007), the contaminated error rate can never be smaller than the optimal value, resulting in a first order influence function identically equal to 0. Second order influence functions need then to be computed. When the optimality does not hold, the first order influence function of the theoretical error rate does not vanish anymore and shows that contamination may improve the error rate achieved under the non-optimal model. The first and, when required, second order influence functions of the theoretical error rate are useful in their own right to compare the robustness of the 2-means and 2-medoids classification procedures. They have also other applications. For example, they may be used to derive diagnostic tools in order to detect observations having an unduly large influence on the error rate. Also, under optimality, the second order influence function of the theoretical error rate can yield asymptotic relative classification efficiencies. [less ▲]

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See detailBlack-grass Resistance to Herbicides: Three Years of Monitoring in Belgium
Henriet, François; Maréchal, Pierre-Yves ULg

in Communications in Agricultural and Applied Biological Sciences (2009, May 19)

Black-grass (Alopecurus myosuroides HUDS.) is a common weed of cereal crops widely spread in Northern Europe. Even if the first Belgian case of resistance was reported in 1996, until now, Belgium was ... [more ▼]

Black-grass (Alopecurus myosuroides HUDS.) is a common weed of cereal crops widely spread in Northern Europe. Even if the first Belgian case of resistance was reported in 1996, until now, Belgium was quite spared of this problem and only a few restricted areas were con-cerned: the Polders, the marshland of the Escaut River and the Fosses-la-Ville region. About 90 seed samples were collected trough the South part of Belgium and in the Polders during July 2006, 2007 and 2008. These populations were tested in greenhouse conditions by spraying plantlets with herbicides of three modes of action. The herbicides used were photo-synthesis inhibitor, ACCase inhibitors and ALS inhibitors. Susceptible and resistant standard populations (Rohtamsted and Peldon) were included in the test in order to validate it and to permit wild populations classification according to “R” rating system. Populations showed differences of susceptibility to photosynthesis inhibitor, ACCase inhibitors and ALS inhibitors. For each herbicide mode of action, it was possible to find at least one population in each resistance class of the “R” rating system. Furthermore, it appeared that resistance was not confined to restricted areas listed above anymore. [less ▲]

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See detailUse of the supercritical fluid technology to prepare efficient nanocomposite foams for environmental protection purpose
Urbanczyk, Laetitia ULg; Thomassin, Jean-Michel ULg; Huynen, Isabelle et al

Conference (2009, May 19)

This work reports on the preparation of novel nanocomposite foams that are efficient broadband microwave absorbers. Carbon nanotubes are first successfully dispersed into PCL and PMMA by melt blending ... [more ▼]

This work reports on the preparation of novel nanocomposite foams that are efficient broadband microwave absorbers. Carbon nanotubes are first successfully dispersed into PCL and PMMA by melt blending. Then, foaming is promoted by supercritical CO2 by depressurization. Regular cellular structures are obtained in both cases with cells size around 10-50µm. The electromagnetic interference (EMI) shielding efficiency of these materials are then evaluated and compared to the non-foamed nanocomposites. [less ▲]

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See detailTreatment influence on herbicide resistance level of Belgian Alopecurus myosuroides populations (black-grass)
Maréchal, Pierre-Yves ULg; Henriet, François; Bodson, Bernard ULg

in Communications in Agricultural and Applied Biological Sciences (2009, May 19), 74(2), 505-514

Black-grass is a common grass weed, widely spread in Northern Europe and also in Belgium. For ages, it has been an increasing problem in industrial crops, especially winter cereals. Therefore, farmers ... [more ▼]

Black-grass is a common grass weed, widely spread in Northern Europe and also in Belgium. For ages, it has been an increasing problem in industrial crops, especially winter cereals. Therefore, farmers started to spray herbicide intensively and soon cases of failure occurred for different molecules and different modes of action. Black-grass populations have been tested in greenhouses to assess the influence of an herbicide treatment as to the resistance level regarding three different herbicides: chlortoluron, fenoxaprop-P and mesosulfuron+iodosulfuron. Black-grass seeds were collected in field trials in six locations in Belgium, on individuals which have survived the herbicide treatment. Each population comes from trial plots, measuring 2 meters wide by 5 meters long and characterized by a single or a combination of products. Herbicides sprayed were isoproturon, flufenacet+diflufenican, ACCase inhibitors and ALS inhibitors. Seeds were also collected in the untreated plots. The population present in these last ones corresponds to the former population, before the herbicide selection pressure was applied. In the glasshouse assay, this population was used as the standard population to compare with other populations issued from the same field. The 'R' rating system was set up with this population to assess the evolution of resistance level, year in, year out. Rothamsted and Peldon populations were also included as cross-reference. Each field population presented different behaviours towards herbicide applied in greenhouses and some cases of resistance can be highlighted. Generally, a reduction of treatment efficiency between field and greenhouse results was clearly visible for the whole of studied active ingredients. Indeed, a distribution shift of the populations towards higher resistance classes could be observed. This is particularly remarkable for active ingredients sharing the same mode of action. For example, it has been found that populations already sprayed with fenoxaprop-P on the field showed a higher resistance level to fenoxaprop-P than to mesosulfuron in the greenhouse test. [less ▲]

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See detailPreparation of living polymer microspheres by dispersion atom transfer radical polymerization in scCO2 using fluorinated macroligands
Grignard, Bruno ULg; Calberg, Cédric ULg; Jérôme, Christine ULg et al

Poster (2009, May 19)

Due to an increasing need for polymers with well-defined architecture (diblock-, graft-, star-shaped copolymers), molecular weight and/or functional end-groups, the use of controlled radical ... [more ▼]

Due to an increasing need for polymers with well-defined architecture (diblock-, graft-, star-shaped copolymers), molecular weight and/or functional end-groups, the use of controlled radical polymerization (CRP) in scCO2 has started to gain attention. Among all the controlled processes, Atom Transfer Radical Polymerization has emerged as a robust tool for the preparation of polymers with well-defined molecular weight, architecture and chain-end functionality. In a very recent paper, we reported the first efficient dispersion ATRP of methyl methacrylate (MMA) in scCO2 using a fluorinated polymeric ligand that had a dual role, i.e., the complexation of the copper salt and the stabilization of PMMA growing particles. In this contribution, we extended this new system to the dispersion ATRP of styrene, to the synthesis of diblock copolymers beads and the controlled synthesis of hyperbranched copolymers. Finally, because both ATRP and alkyne-azide Huisgen’s 1,3-dipolar cycloaddition relies on the use of a Cu(I) catalyst, synthesis of pyrene end-functionalized polymers by simultaneous dispersion ATRP and click reaction was also investigated in supercritical carbon dioxide. [less ▲]

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See detailBacillus-based biocontrol of Fusarium disease on tomato cultures in Burundi
Nihorimbere, Venant; Ongena, Marc ULg; Cawoy, Hélène ULg et al

Poster (2009, May 19)

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See detailDevelopment of a small-scale scroll expander-based ORC
Quoilin, Sylvain ULg

Conference (2009, May 19)

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See detailEvaluation of realtime spray drift using RTDrift Gaussian advection-diffusion model
Lebeau, Frédéric ULg; Verstraete, Arnaud ULg; Schiffers, Bruno ULg et al

in Spanoghe, Pieter (Ed.) COMMUNICATIONS IN AGRICULTURAL AND APPLIED BIOLOGICAL SCIENCES (2009, May 19)

A spray drift model was developed to deliver real time information to the pesticide applicator. The sprayer is equipped with sensors to deliver real time measurement of operational parameters as spray ... [more ▼]

A spray drift model was developed to deliver real time information to the pesticide applicator. The sprayer is equipped with sensors to deliver real time measurement of operational parameters as spray pressure, boom height, horizontal boom movements and geolocalization. The spray droplet size spectrum as a function of pressure was characterized using PDI measurements. Wind speed and direction were measured using a sprayer mounted 2-D ultrasonic anemometer. For each successive boom position, a diffusion-advection Gaussian tilting plume model is used to compute the spray drift deposits downwind. Drift is computed independently for each droplet classes and each nozzle based on the operating parameters. Field trials were performed on a test plot in various wind conditions. The ground drift was measured for different drift distances using fluorimetry analysis. Results show that drift deposits are mainly affected by wind speed and direction what was correctly accounted for by the model. Short distance drift deposits values were overestimated by the model while long distance drift was underestimated. It appears that this most probably origins from embarked wind speed measurements and diffusion parameter. It is concluded that a treatment of embarked wind speed and diffusion measurement should be used to minimize these errors. [less ▲]

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See detailDetection of accase target-site resistant Alopecurus myosuroides huds (black-grass) in Belgian populations
Maréchal, Pierre-Yves ULg; Henriet, François; Bodson, Bernard ULg

in Communications in Agricultural and Applied Biological Sciences (2009, May 19)

Black-grass is a common grass weed, widely spread in Northern Europe and also in Belgium. For ages, it has been an increasing problem in industrial crops, especially winter cereals. The first case of ... [more ▼]

Black-grass is a common grass weed, widely spread in Northern Europe and also in Belgium. For ages, it has been an increasing problem in industrial crops, especially winter cereals. The first case of resistance in Belgium was reported in 1996 by Robert Bulcke (Eelen et al., 1996). Yet the resistance mechanism was not specified. Since then, no more information was published about the evolution Belgium, while research continued in the United Kingdom and in France. Moreover, during the last decade, progress in molecular biology allowed to highlight the mechanism of target-site resistance. A simple PCR method allows to detect the mutation conferring resistance to herbicide. After two years of resistance monitoring in Belgium, mostly in the Walloon part, some populations have been clearly identified as highly resistant to ACCase inhibitor. These populations have been tested by molecular biology so as to detect the single nucleotide polymorphism (SNP) involved in this case. The method employed was the Polymerase Chain Reaction Allele Specific Assays (PASA: Délye, 2002a) for the mutation Ile-1781-Leu that confers a target-site resistance to ACCase inhibitors. Those analyses were performed on plant material issued from bioassays, either in glasshouses or in Petri dishes. Leaves have been collected from plants which survived a fenoxaprop-P treatment applied in a glasshouse single dose assay. Seedlings from resistant populations grown in Petri dishes containing either fenoxaprop-P or cycloxydim provided the second type of sample. Ile1781 mutants were discovered within three populations. Each mutant plant was heterozygote. Five of those samples have been sequenced to confirm PASA results and everyone was matching. Moreover, they were all issued from Petri dishes containing cycloxydim, known to be unaffected by enhanced metabolism, confirming that theses populations are indeed target-site resistant. [less ▲]

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See detailMONITORING OF THE ENTOMOLOGICAL DIVERSITY IN A PESTICIDE FREE ORCHARD: INVESTIGATION OF THE GEMBLOUX AGRICULTURAL UNIVERSITY CONSERVATORY
Poligui, René Noël ULg; Haubruge, Eric ULg; Francis, Frédéric ULg

Poster (2009, May 19)

In orchards, the fruit production is currently oriented to integrated pest management. In order to develop efficient pest control strategy by using entomophagous beneficial and lowering the application of ... [more ▼]

In orchards, the fruit production is currently oriented to integrated pest management. In order to develop efficient pest control strategy by using entomophagous beneficial and lowering the application of pesticides, sufficient knowledge of entomological populations is needed. Here, a systematic monitoring of insect diversity and abundance in a conservatory orchard of Gembloux was performed. Combining yellow traps and visual observations, 19 pest and 34 beneficial families were identified among the 10766 and 3985 insects caught in yellow traps and visual observations respectively. Calculation of diversity indices allowed us to demonstrate the variability according to fruit tree species and insects observation method. Highest insects diversity was registered in apple, then in cherry and finally in the apple-pear association and plum. Pests and beneficials represented 27% and 39% of the insect collections respectively. Aphids represented from 81% to 95%of pests depending on fruit tree species and observation method. The predominant specie was Brachycaudus helychrysi (Kaltenbach). Aphidophagous guild was largely present and mainly constituted by coccinellids and hoverflies. Harmonia axyridis Pallas and Episyrphus balteatus De Geer were the most abundant. Aphididae was found to be the most common orchard pests with a range of related aphidophagous beneficials. These results highlight the need leading to potential reasoning . [less ▲]

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Peer Reviewed
See detailExtending the job Demands-Resources Model : safety behaviour and perceived safety climate.
Hansez, Isabelle ULg; Chmiel, N.

Conference (2009, May 16)

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See detailLes stratégies wallonnes en matière de simplification administrative
Thoreau, François ULg

Conference (2009, May 15)

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See detailLes principles de l’Eco-conception
Reiter, Sigrid ULg

Conference (2009, May 15)

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See detailLa couleur des dehors dans les traités d’architecture français, XVIe-XVIIIe siècle
Gilles, Isabelle ULg

Conference (2009, May 15)

Témoin fondamental pour l’étude du bâti, le traité d’architecture constitue une source textuelle et iconographique, et plus généralement un document contextuel, qui détermine les règles de l’architecture ... [more ▼]

Témoin fondamental pour l’étude du bâti, le traité d’architecture constitue une source textuelle et iconographique, et plus généralement un document contextuel, qui détermine les règles de l’architecture dans ses dimensions les plus vastes : culturelles, sociales, économiques, techniques… Ainsi, dans le domaine de la « peinture d’impression », les auteurs nous livrent aussi bien des informations d’ordre technique (matières et mises en œuvre) que les usages d’une architecture pensée et écrite avec soin, dans laquelle chaque élément – et chaque couleur – occupe une place bien déterminée. Si la couleur des « dedans » prend naturellement le dessus dans une conception française de l’architecture qui a poussé au plus haut point l’art de la distribution, la couleur des « dehors » n’est néanmoins pas négligée. Aussi trouverons-nous dans les traités d’architecture les techniques et les usages qui conviennent aux « dehors » ; informations qui sont susceptibles de guider le restaurateur dans les choix d’intervention qu’il projette sur le bâti ancien. [less ▲]

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See detailLes standards internationaux : la place des situations et des contextes
Lafontaine, Dominique ULg

Conference (2009, May 15)

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See detailEco-conception : exemples d'écoquartiers
Marique, Anne-Françoise ULg

Conference (2009, May 15)

Detailed reference viewed: 112 (33 ULg)
See detailA Systems Biology Approach to Apoptosis Signalling
Schliemann, Monica ULg; Scheurich, Peter; Bullinger, Eric ULg

Conference (2009, May 15)

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See detailFunctionalization of aliphatic polyesters by “click chemistry” in supercritical carbon dioxide
Grignard, Bruno ULg; Schmeits, Stephanie ULg; Riva, Raphaël ULg et al

Poster (2009, May 14)

The combination of ring-opening polymerization of lactones and “click” copper-catalyzed Huisgen’s [3+2] cycloaddition is known to be a very efficient strategy for the functionalization of poly(ε ... [more ▼]

The combination of ring-opening polymerization of lactones and “click” copper-catalyzed Huisgen’s [3+2] cycloaddition is known to be a very efficient strategy for the functionalization of poly(ε-caprolactone) (PCL) and poly(lactic acid) (PLA). Whenever the “click” reaction occurs in an organic solvent (THF or DMF), at relatively low temperature (35°C) and within short reaction time (2 hours), no significant degradation of polyester chains is detected. This strategy was implemented in previous works to graft alkynes substituted by different functional groups, such as hydroxyl, tertiary amines, acrylates or ammonium salts onto azide-functionalized PCL. Moreover, this approach was previously extended to the synthesis of grafted copolymers, either by the grafting of omega-alkyne-PEO onto azide-functionalized aliphatic PLA or PCL (“grafting onto” technique) either by grafting of an ATRP initiator followed by the polymerization of vinyl monomers, such as styrene (“grafting from” technique). These functionalized aliphatic polyesters are promising materials for the development of new biomedical devices. In this work, novel conditions were implemented for the “click” reaction in order to avoid the use of organic solvents and to limit the amount of catalyst remnants in functionalized aliphatic polyesters. Toward this end, if was found that the functionalization by “click” chemistry can be efficiently carried out in supercritical carbon dioxide rather than in THF or DMF. For that sake, it turned out necessary to synthesize a perfluorinated polyamine in order to solubilize the catalyst in supercritical carbon dioxide. Aliphatic polyesters are not soluble in supercritical carbon dioxide. Nevertheless, even under heterogeneous conditions, the functionalization of aliphatic polyesters by “click” chemistry is quantitative. Interestingly enough, no degradation was observed. Last but not least, the copper catalyst was easily removed by supercritical fluid extraction leading to a very low content of residual copper in the final copolyester. [less ▲]

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See detailArtisti calabresi e collezioni post-unitarie: alcuni casi di studio
Geremicca, Antonio ULg

Conference (2009, May 14)

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Peer Reviewed
See detailBioadhesive-Inspired AFM Tips
Willet, N.; Giamblanco, N.; Detrembleur, Christophe ULg et al

Conference (2009, May 14)

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Peer Reviewed
See detailFeeling the Force of a Bistable Molecular Shuttle
Lussis, Perrine ULg; Fustin, C.-A; Bertocco, A. et al

Conference (2009, May 14)

Detailed reference viewed: 7 (1 ULg)
Peer Reviewed
See detailBrushes of polymers bearing negatively charged side groups: mimicking natural molecular velcros
Hou, W.; Fustin, C.-A; Theato, P. et al

Poster (2009, May 14)

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See detailpH-sensitive micellar systems for controlled drug delivery: synthesis and structural characterization by small-angle neutron scattering
Joset, Arnaud ULg; Jérôme, Christine ULg; Brulet, Annie et al

Poster (2009, May 14)

The aim of the project is the preparation of micellar nanocarriers made of biocompatibles copolymers and their structural analysis by Small Angle Neutron Scattering (SANS). These micelles could be used in ... [more ▼]

The aim of the project is the preparation of micellar nanocarriers made of biocompatibles copolymers and their structural analysis by Small Angle Neutron Scattering (SANS). These micelles could be used in drug delivery applications to fight cancer1. The hydrophobic polycaprolactone (PCL) core is intended to incorporate the drug. The corona of hydrophilic polyethylene oxide (PEO) stabilizes the nanocarriers with respect to the plasma proteins. The pH in the neighborhood of the tumoral cells is lower than in the healthy cells. We incorporated a pH-sensitive sequence of poly(2-vinylpyridine) (P2VP). As a result, these micelles are expected to deliver their drug near the cancerous cells without affecting the healthy cells. When the pH is acidic, the P2VP is protonated and the chains are repulsive. The micellar size is then larger than in basic pH, when the P2VP is precipitated on the PCL core. We prepared PCL65-b-P2VP31 / PCL65-b-PEO114 and PCL32-b-P2VP52 / PCL36-b-PEO114 50:50 mixtures of diblocks copolymers. The resulting mixed micelles are analyzed by SANS. We developed a theoretical model with a spherical water-free PCL core. The PEO corona is described as consisting of gaussian chains with a thickness estimated as twice the chain gyration radius, Rg. We propose two alternatives for handling the P2VP zone. The P2VP molecules are either assumed to be Gaussian chains or they fill a shell of thickness L with possible water penetration.The fitting of the models to the experimental scattering cross sections leads to important structural parameters like the aggregation number, the core radius, the gyration radius and the thickness of the P2VP shell. [less ▲]

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See detailTagging with leisure needs
Pestieau, Pierre ULg

Conference (2009, May 14)

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See detailSocial and private LTC insurance with variable altruism
Pestieau, Pierre ULg

Conference (2009, May 14)

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See detailTraitements des arthrites septiques chez le veau
Sartelet, Arnaud ULg; Touati, Kamal ULg

Conference (2009, May 14)

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See detailNovel Stealthy Gd(III)-DOTA/polymer Conjugates for Magnetic Resonance Imaging (MRI)
Grogna, Mathurin ULg; Bémelmans, Stéphanie ULg; Vanasschen, Christian ULg et al

Conference (2009, May 14)

Magnetic resonance imaging (MRI) is a routine diagnostic tool in modern clinical medicine. MRI has many advantages as a diagnostic imaging modality. It is noninvasive, delivers no radiation, and has ... [more ▼]

Magnetic resonance imaging (MRI) is a routine diagnostic tool in modern clinical medicine. MRI has many advantages as a diagnostic imaging modality. It is noninvasive, delivers no radiation, and has excellent (submillimeter) spatial resolution. Some Gadolinium(III) complexes are commonly used to enhance the contrast between adjacent tissues when the resolution/sensitivity of MRI is too low. Because free Gd3+ is very toxic in doses required for MRI, Gd(III) is chelated by poly(amino-carboxylate) such as diethylenetriamine pentaacetic acid (DTPA) or 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA). Although DTPA/Gd3+ and DOTA/Gd3+ are water soluble, they have a very short circulation lifetime in blood, a low molecular weight and a short rotational time that make the contrast poor. To enhance the contrast, the Gd3+/complex doses have to be increased. In order to increase the sensitivity of the technique, while not increasing the concentration of the contrast agent, we were investigating different strategies to improve (i) the circulation lifetime in blood, (ii) the relaxation rate of Gd(III) (and consequently, the contrasting efficiency) and (iii) the targeting of the contrast agent. This presentation aims at reporting how a multifunctional (co)polymer can be designed and exploited for improving the contrasting ability and bioavailability of gadolinium-based complexes. [less ▲]

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See detailTraitement des fractures chez les bovins
Sartelet, Arnaud ULg; Mulon, Pierre-Yves

Conference (2009, May 14)

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See detailDispersion nitroxide mediated polymerization of MMA in supercritical carbon dioxide
Grignard, Bruno ULg; Gigmes, Didier; Jérôme, Christine ULg et al

Poster (2009, May 14)

Controlled dispersion Nitroxide Mediated Polymerization (NMP) of methyl methacrylate (MMA) was successfully carried out for the first time in supercritical carbon dioxide (scCO2) in the presence of CO2 ... [more ▼]

Controlled dispersion Nitroxide Mediated Polymerization (NMP) of methyl methacrylate (MMA) was successfully carried out for the first time in supercritical carbon dioxide (scCO2) in the presence of CO2-philic perfluorinated surfactant that was generated “in situ”. The control of the MMA polymerization relies on the strategy developed by Charleux et al. that consists of using a SG1-based alkoxyamine, i.e. the block-builder, in the presence of small amount of styrene. In a first step, CO2 soluble polyheptadecafluorodecylacrylate was prepared in scCO2 using block-builder as an alkoxyamine. In a second step, nitroxide SG1 mediated dispersion polymerization of MMA was conducted at 70°C and 300 bar in the presence of 5 w% of SG1 terminated surfactant compared to the monomer. Different monomer to alkoxyamine molar ratios were investigated in order to target different molecular weights. In each case, the monomer conversion was high (>90 %), the experimental molecular weight was in good agreement with the theoretical value and the polydispersity was narrow (Mw/Mn ~1.2). Moreover, after depressurisation of the cell, PMMA was collected as a free flowing powder consisting of small sized microspheres. [less ▲]

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See detailConformational analysis of new 5-HT1A ligands by molecular modeling
Dilly, Sébastien ULg; Graulich, Amaury; Liégeois, Jean-François ULg

Conference (2009, May 14)

5-HT1A receptors represent a major target for research and drug development due to their involvement in pathologies such as anxiety,1 depression,2 sleep and memory disorders,3,4 and schizophrenia.5 The ... [more ▼]

5-HT1A receptors represent a major target for research and drug development due to their involvement in pathologies such as anxiety,1 depression,2 sleep and memory disorders,3,4 and schizophrenia.5 The main feature of many drugs having a 5-HT1A affinity is the presence of arylpiperazine moiety.6 Indeed, the protonated nitrogen and the aromatic ring of the arylpiperazine compounds are considered crucial for the interaction with the receptor.7 Interestingly, an in vitro binding study realized in our laboratory reveals the presence of the 1,2,3,6-tetrahydropyridine instead of the piperazine moiety in 4-arylpiperazine-ethyl carboxamide derivatives is highly favourable for 5-HT1A affinity. In order to better understand the favourable effect of this chemical modification, we have performed a conformational analysis of these compounds mainly based on the position of the phenyl ring relative to the piperazine and tetrahydropyridine ones. In the piperazine compounds, the phenyl ring is found in a perpendicular orientation, whereas an almost planar orientation seems to be the most favourable conformation for the tetrahydropyridine compounds (See figure). Therefore, the almost planar orientation of the 4-substituted phenyl ring appears as an important spatial requirement for an optimal interaction with the receptor binding site. This finding could lead to new ideas in the design of high-affinity 5-HT1A ligands. [less ▲]

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See detailMannosylated amphiphilic and degradable PEO-b-PCL copolymers for drug delivery systems: preparation and sugar availability characterizations
Freichels, Hélène ULg; Imberty, Anne; Auezély-Velty, Rachel et al

Poster (2009, May 14)

Over the last decade, polymer micelles and nanoparticles attracted an increasing interest in pharmaceutical research because they can be used as efficient drug delivery systems. In this field, amphiphilic ... [more ▼]

Over the last decade, polymer micelles and nanoparticles attracted an increasing interest in pharmaceutical research because they can be used as efficient drug delivery systems. In this field, amphiphilic copolymers combining poly(ethylene oxide) and aliphatic polyester (such as poly(ε-caprolactone) (PCL) or polylactide (PLA)) are particularly of interest because (i) PEO has unique protein- repellent properties and thus provides a stealth behaviour to the drug carriers and (ii) aliphatic polyesters are biocompatible and biodegradable hydrophobic matrices well-suited for the incorporation of an hydrophobic drug. By end-capping the hydrophilic segment by a targeting moiety so that they may interact with membrane receptors, the biodistribution of polymeric micelles and nanoparticles stabilized with this copolymer can be modulated and can induce specific cellular uptake by receptor-mediated endocytosis. One class of interesting targeting agent is the saccharides, in particular the mannose, because of its specific interaction with mannose receptor, which are found on peripheral and bone marrow macrophages, dendritic cells and sinusoidal liver cells. In this study, the reductive amination reaction is use to attach this targeting agent. After optimisation of the reaction with amino fluorescein, a model amine, mannosylated copolymer of PEO and PCL has been prepared. The surface availability of the saccharide upon the micelles in aqueous phosphate buffer was then assessed by DLS through binding with the protein Concanavalin A (ConA), a known mannose receptor. The interactions between the Bcla lectin and the mannosylated micelles have then been studied by Isothermal Titration Calorimetry (ITC) and the thermodynamic parameters have been obtained. This polymer is particularly useful for the stabilization of PLGA nanoparticles with the goal to target M cells for oral vaccination. [less ▲]

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See detailFeeling the force of a synthetic molecular shuttle
Lussis, Perrine ULg; Willet, Nicolas ULg; Bertocco, Andrea et al

Conference (2009, May 14)

The widespread utilization of sub-molecular motion in key biological processes is inspiring chemists that have been trying to synthesize molecular machines able to imitate the machinery of biological ... [more ▼]

The widespread utilization of sub-molecular motion in key biological processes is inspiring chemists that have been trying to synthesize molecular machines able to imitate the machinery of biological world. In recent years, it has been proved possible to design synthetic molecular systems in which positional displacements of sub-molecular components occur upon the application of external stimuli.[1-4] The architecture of synthetic systems is crucial to translate molecular level effect into a useful response exploitable in the macroscopic world. The pioneering work of Stoddart, Sauvage and others[1-3] has shown that molecular machines with mechanically interlocked architecture are particularly suited for these sorts of applications, because they permit the controlled, large amplitude, movement and positioning of one mechanically interlocked component with respect to another. Among these architectures, rotaxanes -i.e. molecules consisting of a ring threaded on a linear molecule capped with bulky end stoppers- are a particularly promising kind of synthetic 'molecular shuttles'. Truly functional systems based on synthetic molecular machines have not yet been proposed because some key questions remain unanswered: What are the structural features necessary for molecules to convert this controlled motion into useful function? At what level (single molecule, nanoscopic, microscopic, macroscopic) can this be done? Can we address and utilize the induced-motion in a single molecular machine? To answer those questions we are advocating the use of molecular shuttles coupled to a polymeric scaffold and interfaced with AFM. We are convinced that this is an efficient route to translate the sub-molecular motion into a useful response that can be exploited to perform physical tasks Our objective is to demonstrate the feasibility of transducing sub-molecular movements into mechanical work by combining the controlled translational motion of the ring in a rotaxane coupled to a polymer chain, and the ability of AFM-based single molecule force spectroscopy to be used as a mechanical device.[5] For that purpose, a bistable hydrogen-bonded rotaxane with one fumaramide and one succinic amide ester station was synthesized. The equilibrium distribution of the ring between the two stations is in favour of the fumaramide station (>95%).[6] If an external force forces the ring to leave the preferred binding site, it will move back to this preferred binding site through biased Brownian motion. We have attached a poly-ethylene oxide (PEO) chain to the ring and the resulting rotaxane-polymer compound was grafted onto gold substrates. We then fished the PEO chain with an AFM tip. The applied force exerted on the ring when pulling on the polymer chain causes the H bonds linking the ring to the fumaramide station to break. When trying to move away the ring, it shuttles back to its station in the opposite direction of the pulling force, doing work against the AFM cantilever. We have estimated the work done by the ring and show that the value is in good agreement with the theoretical value predicted by Altieri et. al.[6] [1] Special Issue on Molecular Machines, Acc. Chem. Res. 2001, 34, p. 409-522. [2] V. Balzani, A. Credi, M. Venturi, Molecular Devices and Machines – A Journey into the Nano World, Wiley-VCH, Weinheim, Germany, 2003. [3] E R Kay, D A Leigh and F Zerbetto, Angew. Chem. Int. Ed. 2007, 46, 72. [4] a) V Bermudez, N Capron, T Gase, F G Gatti, F Kajzar, D A Leigh, F Zerbetto and S Zhang, Nature, 2000, 406, 608. b) A M Brouwer, C Frochot, F G Gatti, D A Leigh, L Mottier, F Paolucci, S Roffia, G W H Wurpel, Science , 2001, 291, 2124. c) D A Leigh, J K Y Wong, F Dehez and F Zerbetto, Nature, 2003, 424, 174. d) J V Hernandez, E R Kay and D A Leigh, Science, 2004, 306, 153. e) E R Kay and D A Leigh, Nature, 2006, 440, 286. f) V Serreli, C-F Lee, E R Kay and D A Leigh, Nature, 2007, 445, 523. [5] T. Hugel, N. B. Holland, A. Cattani, L. Moroder, M. Seitz, H. E. Gaub, Science 2002, 296, 1103. [6] A. Altieri, G. Bottari, F. Dehez, D A Leigh, J.K.Y Wong, F Zerbetto, Angew. Chem. Int. Ed. 2003, 42, 2296. [less ▲]

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See detailQuand écrire, c'est apprendre (ou versus)
Scheepers, Caroline ULg

Conference (2009, May 13)

Depuis quelques années, la littérature scientifique et le prescrit légal belge mettent l’accent, en formation d’enseignants, sur la formation à la réflexivité. La présente contribution porte sur une ... [more ▼]

Depuis quelques années, la littérature scientifique et le prescrit légal belge mettent l’accent, en formation d’enseignants, sur la formation à la réflexivité. La présente contribution porte sur une recherche-formation longitudinale conduite auprès d’une cohorte de futurs instituteurs du primaire. Ceux-ci ont été enrôlés dans de multiples tâches scripturales sollicitant une posture réflexive : journal de formation, portfolio, travail de fin d’études… En outre, ils ont été invités à proposer à leur tour un écrit réflexif auprès d’élèves du primaire. Les traces sémiotiques recueillies seront envisagées sous l’angle particulier des apprentissages qui y sont mis en perspective. [less ▲]

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See detailLe Dossier Professionnel Réflexif (DPR) en didactique des Langues et littératures modernes à l'ULg : un outil pour développer l'esprit critique et l'autonomie des futurs enseignants
Simons, Germain ULg

Conference (2009, May 13)

Depuis l'année académique 2007-2008, le service de didactique des Langues et littératures modernes de l'ULg a introduit un Dossier Professionnel Réflexif (DPR) qui clôture la formation de l'AESS du Master ... [more ▼]

Depuis l'année académique 2007-2008, le service de didactique des Langues et littératures modernes de l'ULg a introduit un Dossier Professionnel Réflexif (DPR) qui clôture la formation de l'AESS du Master/à finalité didactique. Ce DPR, sorte de "portfolio", vise à amener les étudiants à prendre distance par rapport à leur formation, à s'auto-évaluer en tant que professeur-stagiaire, et à imaginer des pistes de solution afin de s'améliorer dans le futur. La présente communication décrit et commente le dispositif mis en place et fournit quelques éléments d'évaluation. [less ▲]

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See detailAdolescents délinquants sexuels : délinquance et sexualité de ces adolescents à la lumière de leur timing pubertaire .
Glowacz, Fabienne ULg

Conference (2009, May 12)

De nombreuses recherches ( Haynie 2006, Kaltiala-Heino 2003, Parent, 2003, Beaver 2005, Lynne 2007,..) ont établi ces dernières années un lien entre le développement pubertaire et l’engagement dans des ... [more ▼]

De nombreuses recherches ( Haynie 2006, Kaltiala-Heino 2003, Parent, 2003, Beaver 2005, Lynne 2007,..) ont établi ces dernières années un lien entre le développement pubertaire et l’engagement dans des comportements délictueux, usage de drogue, conduites sexuelles et autres comportements exploratoires et déviants. Felson et Haynie (2002) affirment que le développement pubertaire a des effets sur différents types de délinquance, comparables à d’autres puissants prédicteurs de la délinquance. Bien que l’étude de Williams et Dunlop (1999) constate que les garçons à maturité précoce et tardive présentent des taux plus élevés de délinquance que leurs pairs à maturation normale, des recherches plus récentes (Ge 2002, Beaver 2005, Michaud 2006, Lynne 2007)…) soutiennent l’hypothèse de la précocité pubertaire en tant que facteur de risque : les garçons à puberté précoce ont un plus haut niveau d’engagement dans des comportements délinquants, agressifs et sexuels, alors que les garçons à puberté tardive s’engagent dans moins de délinquances (de type crime, violence, atteintes aux biens, usage de drogue et sexualité). Tous les auteurs reconnaissent la complexité des interactions entre facteurs biologiques et psychosociaux, et des liens entre puberté-comportements. La délinquance sexuelle juvénile, au croisement de la délinquance et de la sexualité, ne peut se dispenser d’un questionnement sur le développement pubertaire de ces adolescents . Dans le cadre de notre recherche « Adolescence, délinquances et processus pubertaires », nous avons évalué le timing pubertaire de 47 adolescents ayant commis une agression sexuelle que nous avons comparé à celui d’adolescents délinquants non sexuels (N=20) et d’adolescents non délinquants (N=249). Nos analyses confirment la pertinence de la prise en compte du développement pubertaire de l’adolescent et de ses répercussions psychologiques et sociales dans l’étude des conduites sexuelles délinquantes des adolescents. Les résultats reflètent une surreprésentation de « pubertés décalées » (avancées ou retardées) parmi les adolescents délinquants sexuels comparativement aux adolescents non délinquants, ainsi que des spécificités de la délinquance sexuelle par rapport à d’autres type délinquances. Ces résultats seront discutés dans une perspective biopsychosociale au travers d’une analyse des interactions entre timing pubertaire et socialisation, perception de soi et agressivité des adolescents délinquants sexuels. [less ▲]

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See detailDetecting Triangle Inequality Violations in Internet Coordinate Systems by Supervised Learning
Liao, Yongjun ULg; Kaafar, Mohamed Ali; Gueye, Bamba et al

in Lecture Notes in Computer Science (2009, May 12), 5550

Internet Coordinates Systems (ICS) are used to predict Internet distances with limited measurements. However the precision of an ICS is degraded by the presence of Triangle Inequality Violations (TIVs ... [more ▼]

Internet Coordinates Systems (ICS) are used to predict Internet distances with limited measurements. However the precision of an ICS is degraded by the presence of Triangle Inequality Violations (TIVs). Simple methods have been proposed to detect TIVs, based e.g. on the empirical observation that a TIV is more likely when the distance is underestimated by the coordinates. In this paper, we apply supervised machine learning techniques to try and derive more powerful criteria to detect TIVs. We first show that (ensembles of) Decision Trees (DTs) learnt on our datasets are very good models for this problem. Moreover, our approach brings out a discriminative variable (called OREE), which combines the classical estimation error with the variance of the estimated distance. This variable alone is as good as an ensemble of DTs, and provides a much simpler criterion. If every node of the ICS sorts its neighbours according to OREE, we show that cutting these lists after a given number of neighbours, or when OREE crosses a given threshold value, achieves very good performance to detect TIVs. [less ▲]

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See detailModélisation de l’ionosphère pour les utilisateurs Galileo simple fréquence
Bidaine, Benoît ULg

Conference (2009, May 11)

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See detailObserver l’écoute : du paradoxe à l’enquête
Colon, Paul-Louis ULg

Conference (2009, May 11)

La communication faisait un état critique des techniques d'observation de la perception auditive qui tiennent compte de sa dimension sociale et culturelle.

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See detailSupporting cell cytoskeleton during development of the organ of Corti in rat
Johnen, Nicolas ULg; Thelen, Nicolas ULg; Malgrange, Brigitte ULg et al

Poster (2009, May 11)

The mammalian auditory organ, the organ of Corti (OC), is composed of mechanosensory hair cells and nonsensory supporting cell types. Based on their morphology and physiology, a least four types of ... [more ▼]

The mammalian auditory organ, the organ of Corti (OC), is composed of mechanosensory hair cells and nonsensory supporting cell types. Based on their morphology and physiology, a least four types of supporting cells can be identified in the OC: inner pillar cell, outer pillar cell, phalangeal cell and Deiter’s cells. All supporting cells are highly specialized cells that are characterized by the presence of bundled microtubules with 15 protofilaments instead of 13. Using antibobies against different proteins of cytoskeleton (tubulin, cutokeratin and vimentin), we investigated by confocal microscopy the setting up of supporting cells' cytoskeleton during the differentiation of the OC in art from the embryonic day 18 (E18) to the postnatal 15 (P15). We showed that the inner pillar cells are labelled with an anti-beta IV tubulin from P0. Using an antibody to cytokeratin, a labelling appeared in Deiters' cells from E22. We also revealed that during the development of the OC, supporting cells were labelled with an anti-vimentin antibody from P0. [less ▲]

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See detailHow much more Economics is the New Approach ?
Sibony, Anne-Lise ULg

Conference (2009, May 11)

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See detailMulti-Criteria Decision Support for Cost Assessment Techniques in Shipbuilding Industry
Caprace, Jean-David ULg; Rigo, Philippe ULg

in COMPIT'09, Budapest (2009, May 10)

Cost is perhaps the most influential factor in the outcome of a product or service within many of today’s industries. Cost assessment during the early stage of ship design is crucial. It influences the go ... [more ▼]

Cost is perhaps the most influential factor in the outcome of a product or service within many of today’s industries. Cost assessment during the early stage of ship design is crucial. It influences the go, no-go decision concerning a new development. Cost assessment occurs at various stages of ship design development. Economic evaluation as early as possible, in the design phase, is therefore crucial to find the best price–function compromise for the ship projects. This paper presents a Multi Criteria Decision Aid (MCDA) method in order to select an appropriate cost assessment method at each stage of the ship design. In order to compare the cost performance between all alternatives, the evaluation of each alternative is performed by PROMETHEE. [less ▲]

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See detailSpace Allocation Optimization Applied to Lower Hulls’ Production of Semi-Submersible Platforms
Caprace, Jean-David ULg; Marins, Cassiano; Losseau, Nicolas ULg et al

in COMPIT'09 (2009, May 10)

This paper presents a part of new developments included inside a holistic optimisation strategy during the design cycle of ships. The first part of the paper describes an algorithm to maximize the number ... [more ▼]

This paper presents a part of new developments included inside a holistic optimisation strategy during the design cycle of ships. The first part of the paper describes an algorithm to maximize the number of ship blocks and ship sections to produce in workshops during a certain time window. A tool was developed in order to support planners to improve the space utilization and workshop productivity. Thanks to this software, the scheduling is now done more efficiently and above all it takes less time. The second part of the paper describes a recent development of an algorithm able to generate a feasible blocks erection sequence starting from the blocks splitting definition. The idea is to integrate this module as a new functionality inside simulation software in order to take into account blocks sequence during the elaboration of the optimised production strategy. The two developments were validated on the lower hull of a semi-submersible platform coming from a new Brazilian shipyard. [less ▲]

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See detailLe training chirurgical du médecin généraliste
Belche, Jean ULg

Conference (2009, May 09)

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See detailCoeur et Diabète. Objectifs de prévention cardiovasculaire
RADERMECKER, Régis ULg

Conference (2009, May 09)

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See detailManipulating single molecules with the AFM
Duwez, Anne-Sophie ULg

Conference (2009, May 08)

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See detailLe lac Kivu: bilan des connaissances scientifiques et gestion de ses ressources
Darchambeau, François ULg; Descy, Jean-Pierre

Conference (2009, May 08)

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See detailFeeling the force of a synthetic molecular shuttle
Lussis, Perrine ULg; Fustin, Charles-André; Bertocco, Andrea et al

Poster (2009, May 08)

The widespread utilization of sub-molecular motion in key biological processes is inspiring chemists that have been trying to synthesize molecular machines able to imitate the machinery of biological ... [more ▼]

The widespread utilization of sub-molecular motion in key biological processes is inspiring chemists that have been trying to synthesize molecular machines able to imitate the machinery of biological world. In recent years, it has been proved possible to design synthetic molecular systems in which positional displacements of sub-molecular components occur upon the application of external stimuli.[1-4] The architecture of synthetic systems is crucial to translate molecular level effect into a useful response exploitable in the macroscopic world. The pioneering work of Stoddart, Sauvage and others[1-3] has shown that molecular machines with mechanically interlocked architecture are particularly suited for these sorts of applications, because they permit the controlled, large amplitude, movement and positioning of one mechanically interlocked component with respect to another. Among these architectures, rotaxanes -i.e. molecules consisting of a ring threaded on a linear molecule capped with bulky end stoppers- are a particularly promising kind of synthetic 'molecular shuttles'. Truly functional systems based on synthetic molecular machines have not yet been proposed because some key questions remain unanswered: What are the structural features necessary for molecules to convert this controlled motion into useful function? At what level (single molecule, nanoscopic, microscopic, macroscopic) can this be done? Can we address and utilize the induced-motion in a single molecular machine? To answer those questions we are advocating the use of molecular shuttles coupled to a polymeric scaffold and interfaced with AFM. We are convinced that this is an efficient route to translate the sub-molecular motion into a useful response that can be exploited to perform physical tasks Our objective is to demonstrate the feasibility of transducing sub-molecular movements into mechanical work by combining the controlled translational motion of the ring in a rotaxane coupled to a polymer chain, and the ability of AFM-based single molecule force spectroscopy to be used as a mechanical device.[5] For that purpose, a bistable hydrogen-bonded rotaxane with one fumaramide and one succinic amide ester station was synthesized. The equilibrium distribution of the ring between the two stations is in favour of the fumaramide station (>95%).[6] If an external force forces the ring to leave the preferred binding site, it will move back to this preferred binding site through biased Brownian motion. We have attached a poly-ethylene oxide (PEO) chain to the ring and the resulting rotaxane-polymer compound was grafted onto gold substrates. We then fished the PEO chain with an AFM tip. The applied force exerted on the ring when pulling on the polymer chain causes the H bonds linking the ring to the fumaramide station to break. When trying to move away the ring, it shuttles back to its station in the opposite direction of the pulling force, doing work against the AFM cantilever. We have estimated the work done by the ring and show that the value is in good agreement with the theoretical value predicted by Altieri et. al.[6] [1] Special Issue on Molecular Machines, Acc. Chem. Res. 2001, 34, p. 409-522. [2] V. Balzani, A. Credi, M. Venturi, Molecular Devices and Machines – A Journey into the Nano World, Wiley-VCH, Weinheim, Germany, 2003. [3] E R Kay, D A Leigh and F Zerbetto, Angew. Chem. Int. Ed. 2007, 46, 72. [4] a) V Bermudez, N Capron, T Gase, F G Gatti, F Kajzar, D A Leigh, F Zerbetto and S Zhang, Nature, 2000, 406, 608. b) A M Brouwer, C Frochot, F G Gatti, D A Leigh, L Mottier, F Paolucci, S Roffia, G W H Wurpel, Science , 2001, 291, 2124. c) D A Leigh, J K Y Wong, F Dehez and F Zerbetto, Nature, 2003, 424, 174. d) J V Hernandez, E R Kay and D A Leigh, Science, 2004, 306, 153. e) E R Kay and D A Leigh, Nature, 2006, 440, 286. f) V Serreli, C-F Lee, E R Kay and D A Leigh, Nature, 2007, 445, 523. [5] T. Hugel, N. B. Holland, A. Cattani, L. Moroder, M. Seitz, H. E. Gaub, Science 2002, 296, 1103. [6] A. Altieri, G. Bottari, F. Dehez, D A Leigh, J.K.Y Wong, F Zerbetto, Angew. Chem. Int. Ed. 2003, 42, 2296. [less ▲]

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See detailLe droit de la distribution
Petit, Nicolas ULg

Conference (2009, May 08)

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See detailL’état des stocks de poissons pélagiques : nouvelles évaluations par écho-sondages
Guillard, Jean; Darchambeau, François ULg

Conference (2009, May 08)

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See detailBiodegradable polymers-based nanofibers by electrospinning
Jérôme, Christine ULg

Conference (2009, May 07)

Detailed reference viewed: 13 (3 ULg)
See detailHelioseismic Spectral Diagnostics - An Update
Leibacher, John W; Baudin, F.; Belkacem, Kevin ULg et al

in AAS/Solar Physics Division Meeting (2009, May 01)

In order to test models of the excitation of p modes and their behavior in the visible atmosphere, we calculate time sequences of Fraunhofer absorption line profiles of the Ni, Fe, K, Na, and Ca lines ... [more ▼]

In order to test models of the excitation of p modes and their behavior in the visible atmosphere, we calculate time sequences of Fraunhofer absorption line profiles of the Ni, Fe, K, Na, and Ca lines used in helioseismology, focusing on Sun-as-a-star observations in this initial work. The atmospheric models, which give rise to the line profiles, are based on the VAL-C, perturbed by realistic p-mode eigenfunctions. The time sequences of line profiles are analyzed as for various instruments, to compare predicted and observed mode amplitudes as a function of temporal frequency [less ▲]

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See detailSome theoretical and practical considerations about surface preparation of concrete and adhesion of repair systems.
Courard, Luc ULg; Garbacz, Andrzej; Piotrowski, Tomasz

in Sustercic, Jakob (Ed.) <<<<< (2009, May)

Before any repair operation, an effective assessment of the concrete substrate has to be performed. Usually next to the surface reparation of concrete, evaluation of the cohesion of the superficial ... [more ▼]

Before any repair operation, an effective assessment of the concrete substrate has to be performed. Usually next to the surface reparation of concrete, evaluation of the cohesion of the superficial concrete is requested for adhesion and durability reasons. Many authors describe the influence of the surface preparation technique on the superficial cohesion of concrete or the adhesion. However, the real effects of surface preparation technique only begin to be investigated in terms of superficial microcracking or roughness quantification. This project was performed in regards to the influence of concrete substrate strength and preparation technique efficiency. The effect of the concrete removal/preparation technique is most likely dependent upon the nature and the quality of the concrete substrate. Preparation techniques are compared from the point of view of concrete removing but also potential deterioration. The visual observation of the concrete surfaces indicates that the high pressure water jetting technique induces a particular texture characterized by large waves mostly parallel to the water flow. The concrete slabs have afterwards been covered with a Self-Compacting Repair Mortar and adhesion has been characterized. [less ▲]

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See detailGroup B streptococcal Screening, Diagnosis and Clinically Relevant Resistance
Melin, Pierrette ULg

in DEVANI Training (Ed.) European Workshop Current Insights into Group B Streptococcal Diseases (2009, May)

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See detailDeveloppement et utilisation de modèles de simulation pour l'audit et la rénovation des bâtiments conditionnés
Bertagnolio, Stéphane ULg; Lebrun, Jean ULg; Andre, Philippe ULg

(2009, May)

Une suite d’outils de simulation de bâtiment et de système de climatisation destinés à assister l’audit et la rénovation des bâtiments commerciaux est actuellement en développement. Les outils en question ... [more ▼]

Une suite d’outils de simulation de bâtiment et de système de climatisation destinés à assister l’audit et la rénovation des bâtiments commerciaux est actuellement en développement. Les outils en question sont développés de façon à limiter le nombre de paramètres demandés à l’utilisateur et à garder une transparence totale pour ce dernier. Dans un premier temps, le développement des modèles et leur implémentation dans un solveur d’équations sont discutés. L’identification des paramètres des modèles développés est ensuite discutée et illustrée par un exemple d’application. [less ▲]

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See detailArena Public Outreach
Péronne, M.-L.; Baudouin, C.; Pospieszalska-Surdej, Anna ULg et al

in Spinoglio, L.; Epchtein, N. (Eds.) 3rd ARENA Conference: An Astronomical Observatory at CONCORDIA (Dome C, Antarctica) EAS Publications Series Vol. 40 (2010) (2009, May)

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See detailEvaluation, correction et validation de modèles de composants d'une centrale de production d'eau glacée
Lemort, Vincent ULg; Lebrun, Jean ULg

(2009, May)

Ce papier présente des outils d’évaluation, de correction et de validation des modèles de simulation d’un groupe frigorifique et d’une batterie froide. Après avoir brièvement décrit les modèles, le papier ... [more ▼]

Ce papier présente des outils d’évaluation, de correction et de validation des modèles de simulation d’un groupe frigorifique et d’une batterie froide. Après avoir brièvement décrit les modèles, le papier montre comment leurs paramètres peuvent être identifiés sur base uniquement des performances publiées par les constructeurs. Cette information est incomplète et des hypothèses rationnelles sont proposées. Les modèles sont validés par comparaison des résultats de simulations avec à ceux obtenus au moyen d’autres modèles et/ou avec des données expérimentales. Ces comparaisons conduisent finalement à encore améliorer les modèles et à en ré-ajuster les paramètres. [less ▲]

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See detailUne solution numérique au test de Cattell pour déterminer le nombre de composantes principales à retenir
Raîche, Gilles; Magis, David ULg; Walls, Ted et al

Conference (2009, May)

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See detailProteomic comparison of High and Low responders to eccentric exercise
Hody, Stéphanie ULg; Croisier, Jean-Louis ULg; Leprince, Pierre ULg et al

in Abstract book du Colloque de la Société Belge des Neurosciences (2009, May)

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See detailALMA - Parentalité et alimentation dans les milieux d'accueil collectifs de la petite enfance
Absil, Gaëtan ULg; Demarteau, Michel; Bauwens, Hélène et al

Poster (2009, May)

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See detailComparaison empirique des méthodes classiques de détection du fonctionnement différentiel d’items en psychométrie
Magis, David ULg; De Boeck, Paul; Raîche, Gilles

Conference (2009, May)

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See detailLe Système de Conseil Agricole : pour une synergie du conseil agronomique, zootechnique, économique et conditionnalité au bénéfice de l’éleveur
Gounot, G.; Hanzen, Christian ULg; Hobe, M. et al

in Recueil des journées nationales 2009 (2009, May)

Entré en vigueur en 2008, le Système de Conseil Agricole est un nouveau mode de travail dans le milieu agricole. Les exploitants agricoles ne sont plus en contact direct avec l’administration pour ... [more ▼]

Entré en vigueur en 2008, le Système de Conseil Agricole est un nouveau mode de travail dans le milieu agricole. Les exploitants agricoles ne sont plus en contact direct avec l’administration pour l’application des règles de conditionnalité des aides, mais sont conseillés par des organismes aux compétences multiples. Ces derniers doivent être capables d’apporter les appuis techniques et économiques nécessaires, répondant aux critères imposés par l’administration. On assiste donc à un transfert de compétences et de responsabilité de l’administration vers les SCA. Le fonctionnement des SCA est décrit dans cet article, avec l’exemple d’un réseau de compétences mis en place en Bretagne [less ▲]

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See detailCombine pedigree and marker information into a single estimator for the calculation of relationships
Bömcke, Elisabeth ULg; Gengler, Nicolas ULg

Poster (2009, May)

Relationship coefficients are particularly useful to improve genetic management of endangered populations. Estimation of relationships was traditionally based on pedigree data but, today, numerous methods ... [more ▼]

Relationship coefficients are particularly useful to improve genetic management of endangered populations. Estimation of relationships was traditionally based on pedigree data but, today, numerous methods already exist to replace pedigrees by molecular data. However, genotyping a complete population for a sufficient number of markers can be impossible, e.g., in case of local and/or rare breeds. The idea was therefore to develop a new method to estimate relationship by combining molecular with pedigree data into a single estimator. Originally developed for the management of an endangered horse population, it will be useful for specific situations, where neither pedigree nor molecular data are complete. Two questions appeared: What and how to combine? Following the principle that things have to be similar to be combined, we compared two coefficients that have the advantage to be similarly defined: the additive relationship coefficient (axy) calculated from pedigrees and the total allelic relationship (taxy) obtained from markers. Wright relationship coefficient (rped,xy) were also compared to taxy, transformed into rmol,xy, to highlight the influence of inbreeding. The results showed the influence of inbreeding, of marker quality and the tendency of molecular coefficients to overestimate the relationship among individuals. The method to combine the selected coefficients was also determined. Various parameters were taken into account in the model: number of markers and quality (e.g. marker informativeness), mutation rate, pedigree quality (e.g. generation-equivalents), … The combined estimator has several advantages. Especially, negative relationship values obtained in literature with molecular-based estimators in case of small inbred populations can be avoided. [less ▲]

Detailed reference viewed: 42 (5 ULg)