Biomass hydrolyzing enzymes identified by functional screening of a metagenomic library from algal biofilms.

Poster (2013, June)

Biomass hydrolyzing enzymes are increasingly searched for the production of biofuels and renewable chemical compounds using biomass. Microorganisms living on algaes are an interesting reservoir of biomass ... [more ▼]

Biomass hydrolyzing enzymes are increasingly searched for the production of biofuels and renewable chemical compounds using biomass. Microorganisms living on algaes are an interesting reservoir of biomass hydrolyzing enzymes, as they are in constant interaction with algal biomass. Therefore, we are interested in looking for some of those enzymes synthesized by the microflora living on the surface of the brown algae Ascophyllum nodosum. Algae samples were collected in the winter 2012 and a microbial DNA extraction method was developed. The whole extracted microbial genomes of the microorganisms living on the algae were restricted, inserted in a cloning vector and ligated products were used for transformation of cultivable Escherichia coli host cells. This metagenomic library was then screened for diverse enzymatic activities (lipolytic enzymes, cellulases, beta-glucosidases, alpha-amylases, arabinanases, xylanases and proteases) on agar plates with specific substrates. Five putative lipolytic enzymes, one cellulase and one beta-glucosidase were identified. Sequence analysis revealed low (<50%) sequence identities with known enzymes sequences, meaning new enzymes from unknown genomes have been discovered. To our knowledge this is the first functional screening that was realized with a metagenomic library from algal biofilms and this is the first cellulase identified by marine metagenomics. A second library has been constructed from algae sample from summer 2012 and is currently being screened. New enzymatic tests are being developed for the identification of enzymes degrading specific algal polysaccharides like agarases, carrageenases, alginate lyases, laminarinases,… Those very specific enzymes aren’t well known yet, and our metagenomic approach will probably help us to identify new families and structures of those algal biomass hydrolyzing enzymes. [less ▲]

Determination of activation yield curves for fusion escaping particle diagnostics

Conference (2013, June)

The first three billion years of life Evolution

Conference (2013, June)

Recent advances on aphid alarm pheromone biosynthetic pathway

Conference (2013, June)

Identification of lectins as virus competitors in aphid vectors : from fundamental to applied approaches

Poster (2013, June)

Study of interface trap density in a GeSn MOS structure by numerical simulation of the electrical characteristics

Poster (2013, June)

Optimisation robuste de méthodes SFC par une approche de type design space

Conference (2013, June)

Syndromes canalaires du pied - Apport des bilans électrophysiologiques

Conference (2013, May 29)

Syndromes canalaires rares du membre supérieur - Apport des bilans électrophysiologiques

in 32ème congrès AMDTS (2013, May 27)

Expliquer et illustrer Prospéro. Suivre le marqueur temporel "le-pire-est-à-venir" au sein des agendas politiques climatiques belges (1980-2012)

Conference (2013, May 24)

Individual needs in flexibility and employment security: a qualitative approach

Conference (2013, May 24)

The most non-classical symmetric states of an N-qubit system

Poster (2013, May 23)

A BAYESIAN PROBABILITY CRITERION TO ASSESS ANALYTICAL RESULTS RELIABILITY

Conference (2013, May 21)

In pharmaceutical and biomedical industries, quantitative analytical methods such as HPLC play a key role. Indeed, the analytical results obtained from them are used to make crucial decisions such as the ... [more ▼]

In pharmaceutical and biomedical industries, quantitative analytical methods such as HPLC play a key role. Indeed, the analytical results obtained from them are used to make crucial decisions such as the release of batches of drugs, the evaluation of safety and efficacy of new drug candidates or the monitoring of patients health. Prior to their routine use, analytical methods are submitted to a stringent validation study [1] where they have to demonstrate that they are fit for their final purpose, i.e. providing accurate results: where is the analytical result, is the theoretical unknown true concentration of analyte in the sample analyzed and a regulatory acceptance limit. Typically this demonstration is made by either providing point estimates of systematic error (bias) and random error (variance) or sometimes by providing interval estimates of these statistical parameters at several well defined concentration levels of the target analyte [2]. They are then compared to maximum acceptable levels. More recently, tolerance intervals approaches have been proposed that are evaluated in a similar way at these key concentration levels [3]. However none of these decision approaches allow knowing the probability to obtain accurate results over the whole concentration range of interest: is a vector of parameters and Pmin is a minimum reliability probability. Frequentist approximations have been proposed to estimate this probability but only at the concentration levels experimentally tested [4,5]. In this work, a linear hierarchical Bayesian approach is proposed. It takes into account the potential random characteristic of the slope and intercept observed from one analytical run to the other, but it also integrates the possible covariance between the parameters. Additionally, heteroscedasticity of the residual variance over the concentration range investigated is taken into account. A situation regularly observed in practice. Finally a reliability profile for the whole concentration range studied is obtained using MCMC sampling. This profile provides the probability (Prel) to obtain accurate results over the full concentration range investigated. This profile is then compared to a minimum reliability probability (Pmin) that will define the valid concentration range of the analytical method. The usefulness of this approach is illustrated through the validation of a bioanalytical method and also compared with one concentration level at a time frequentist approaches [4,5]. [1] International Conference on Harmonization (ICH) of Technical Requirements for registration of Pharmaceuticals for Human Use Topic Q2 (R1): Validation of Analytical Procedures: Text and Methodology, Geneva, 2005. [2] A. Bouabidi and al., J. Chromatogr. A, 1217 (2010) 3180. [3] Ph. Hubert and al., J. Pharm. Biomed. Anal., 36 (2004) 579. [4] W. Dewé and al., Chemometr. Intell. Lab. Syst. 85 (2007) 262. [5] B. Govaerts and al., Qual. Reliab. Engng. Int. 24 (2008) 667. [less ▲]

Inceste et Famille: confrontation et complémentarité des notions structuralistes et de pertes ambiguës dans la prise en charge systémique (atelier)

Conference (2013, May 17)

Dans le travail avec les familles connaissant une situation d’inceste, le paradigme structura liste de Minuchin (1974) apparaît souvent comme l’angle d’approche systémique privilégié. Bien qu’initialement ... [more ▼]

Dans le travail avec les familles connaissant une situation d’inceste, le paradigme structura liste de Minuchin (1974) apparaît souvent comme l’angle d’approche systémique privilégié. Bien qu’initialement celui-ci ne s’adresse pas spécifiquement aux situations de maltraitances infantiles et plus particulièrement d’inceste, nous proposons d’illustrer, au travers du cheminement d’une vignette clinique, combien un tel regard permet la mise en lumière du fonctionnement familial et, dans le respect de l’éthique systémique, de dessiner les pistes thérapeutiques par le biais même de la démarche diagnostique. notre pratique clinique dans une équipe spécialisée nous montre cependant que le travail avec la famille connaissant une situation d’inceste ne peut se résumer à mieux comprendre le passé pour préparer l’avenir. en effet, bien souvent, ces familles connaissent une situation qui, selon nous, s’apparente à ce que pauline Boss (1999, 2006) a nommé la perte ambiguë. après un exposé théorique des notions de pertes et de frontières ambiguës (Boss, 1999, 2006) auxquelles il est très certainement moins fréquent de faire appel dans la prise en charge (systémique) de l’inceste, nous montrerons au travers l’exploration de la même vignette clinique pourquoi et comment ce cadre conceptuel a toute sa pertinence dans le travail clinique. enfin, après avoir démontré l’utilité, la complémentarité et les différences entre l’approche de Minuchin et celle de Boss, nous pourrons nous tourner vers les questions soulevées par notre exposé. en effet, dans les situations d’inceste et d’agression sexuelle en général, l’étude des mécanismes à l’œuvre, tant du point de vue individuel que systémique, a permis et permet de mieux comprendre les facteurs impliqués et dès lors de prévenir et soigner. toutefois, s’il est bien naturel que les projecteurs se tournent vers la transgression des interdits sexuels, il n’en reste pas moins que la famille se trouve confrontée, dans l’ici et maintenant, à une inéluctable réorganisation. les difficultés inhérentes à celle-ci, si elles ne sont pas prises en compte, pourraient amener à ne pas permettre l’expression des compétences familiales (ausloos, 1995) au moment où leur évaluation est pourtant requise, et à offrir aux familles un soutien davantage adapté à leur histoire qu’à leur actualité. [less ▲]

Light-induced Hetero-Diels Alder cycloaddition as a new coupling method to biomolecule radiolabeling

Poster (2013, May 16)

The formation of a C-18F bond requires hard conditions which is problematic for the biomolecule radiolabelling. The alternative method which has been developed since a few decades consists in ... [more ▼]

The formation of a C-18F bond requires hard conditions which is problematic for the biomolecule radiolabelling. The alternative method which has been developed since a few decades consists in incorporating the 18F on a prosthetic group and coupling it to the biomolecule. The copper (I)-catalysed 1,2,3-triazole formation involving azides and terminal alkynes is a powerful and rapid method of coupling but present the inconvenient of the employment of cytotoxic reagents. The photoclick conjugation is a promising alternative with no need of catalyst[1]. Recently, a light-induced hetero-Diels Alder cycloaddition involving a 3-(hydroxymethyl)-2-naphthol derivative and an electron-rich olefin has been developed[2]. This reaction seems well adapted for the fast conjugation of radionuclides to biomolecules. Herein we report the synthesis of a [18F]fluoronaphtoquinone derivative as prosthetic group and its reaction with vinyl ethers. [less ▲]

Emotion, mort et conscience. Le premier Sartre et la psychanalyse

Conference (2013, May 16)

Alternative methods for virus control: the role of symbionts and lectins in viral transmission

Conference (2013, May 16)

Risques et défis sécuritaires de la (non)-intégration des Balkans occidentaux dans l’Union européenne

Conference (2013, May 15)

La région des Balkans occidentaux, ces deux dernières décennies, était source de conflits, de guerres, de tensions et de mésententes inter et intra-étatiques, ainsi que d’une instabilité politique et ... [more ▼]

La région des Balkans occidentaux, ces deux dernières décennies, était source de conflits, de guerres, de tensions et de mésententes inter et intra-étatiques, ainsi que d’une instabilité politique et économique. Les querelles permanentes, depuis le XIXe siècle, entre les différents groupes ethniques ont surtout surgit à la fin du siècle dernier au moment de la désintégration de l’ex-Yougoslavie, provoquant une déstabilisation générale de la région dont les conséquences perdurent encore aujourd’hui. Tout au long des années nonante, les instances européennes tentent de contrôler le déroulement des faits, mais les divisions internes sur la question, le défaut de maturité politique et de capacité d’action collective montrent que l’UE n’a joué qu’un rôle accessoire dans la gestion de ces situations problématiques : certains auteurs vont même jusqu’à dire que cette dernière ne peut être qualifié d’acteur international puisque durant cette période elle manque d’autonomie vis-à-vis de ses États membres et de cohérence dans sa stratégie d’action. Raison pour laquelle, les États-Unis, l’Organisation du traité de l’Atlantique du Nord (OTAN) et l’Organisation des Nations unies (ONU) vont occuper la place centrale dans la pacification de la région. Cette incapacité d’action et de stabilisation préoccupe les décideurs européens dans la mesure où ils décident de créer la Politique européenne de sécurité et de défense (PESD) en 1999, et où l’UE finit par prendre de plus en plus de responsabilités dans la gestion de son environnement proche. Dans ce cadre, lors du Conseil européen de Feira (2000) et notamment celui de Thessalonique (2003) l’UE ouvre la perspective d’adhésion aux États balkaniques au « cas par cas », c’est-à-dire selon un processus méritocratique, en adoptant une stratégie d’élargissement vers cette partie du continent européen. À travers ses missions civiles et militaires, sa diplomatie active, ses investissements économiques et commerciaux, son instrument d'aide de préadhésion (IAP), l’UE, ces dix dernières années, est parvenue à s’imposer davantage à tel point qu’elle présente actuellement l’autorité la plus visible dans la région. Toutefois, les États des Balkans occidentaux continuent à présenter des risques et défis sécuritaires puisque même si l’état de guerre dépassé, la paix reste fragile à cause des tensions et des disputes infinies sur des questions sensibles. En conséquence, pour ces pays le chemin d’intégration européenne reste remplit d’obstacles infranchissables, exposant à nouveaux les limites de l’UE en tant qu’« acteur » international à gérer des dossiers délicats qui menacent la stabilité régionale. En effet, l’UE ne parvient toujours pas à régler définitivement la question du nom de la Macédoine car l’un de ses États membres, à l’occurrence la Grèce, s’oppose. De plus, malgré son engagement important, la diplomatie européenne connaît des faiblesses dans la stabilisation de la Bosnie-Herzégovine, pays qui connaît de véritables frictions entre ses différentes communautés. La non-reconnaissance de l’indépendance du Kosovo par l’ensemble des États membres dévoile également l’incapacité de l’UE à agir d’une seule voix. [less ▲]

Synthesis of [18F]4-(4-fluorophenyl)-1,2,4-triazole-3,5-dione: an agent for specific radiolabelling of tyrosine.

in Flagothier, Jessica (Ed.) Journal of Labelled Compounds and Radiopharmaceuticals (2013, May 14)

Objectives: Metal-free and mild tyrosine modification reactions are an attractive alternative to the commonly used lysine and cysteine modification protocols for peptide and proteins labelling. Recently ... [more ▼]

Objectives: Metal-free and mild tyrosine modification reactions are an attractive alternative to the commonly used lysine and cysteine modification protocols for peptide and proteins labelling. Recently, Ban and co-workers have reported a tyrosine bioconjugation through ene-type reactions. Cyclic diazodicarboxamides, which are electrophilic compounds, react selectively in o-position on the phenol side chain of tyrosine in mild aqueous conditions and the 1,2,4-triazolidine-3,5-dione linkage is hydrolytically and thermally stable. We herein present the synthesis of [18F]4-(4-fluorophenyl)-1,2,4-triazole-3,5-dione and the coupling with N-acyl tyrosine methylamide. Methods: The N,N,N-trimethyl-4-nitrobenzeneammonium trifluoromethanesulfonate 1 was prepared following a procedure previously reported [2]. The [18F]prosthetic group 6, [18F]4-(4-fluorophenyl)-1,2,4-triazole-3,5-dione, was synthesized in five steps. Results: The synthesis of the [18F]prosthetic group has been realized with a decay-corrected radiochemical yield of 20% in 90 minutes. The radiochemical yield of the coupling with N-acyl tyrosine methylamide is 40% (DC). This presented synthetic pathway should be easily automated: particulary because the purifications between the different steps are exclusively done on SPE cartridges. Conclusions: We successfully developed an efficient bioconjugation method for fluorine-18 labelling of tyrosine without prior modifications of the peptide in very mild conditions. [less ▲]

Diigo ou l'intégration du Web 2.0 dans un dispositif de blended learning

Conference (2013, May 13)

Une décennie de recherche et de réflexion sur la formation, l'enseignement et l'apprentissage des sciences humaines à l'école primaire au Québec : lignes de force et pistes de recherche

Conference (2013, May 09)

Cette présentation avait pour ambition de dégager les lignes de force des différentes communications présentées durant le colloque, de les mettre en contexte par rapport à l'état de la recherche en Europe ... [more ▼]

Cette présentation avait pour ambition de dégager les lignes de force des différentes communications présentées durant le colloque, de les mettre en contexte par rapport à l'état de la recherche en Europe fracophone et de suggérer un certain nombre de pistes de recherche et d'action. [less ▲]

The influence of biogeochemical processes on the pH dynamics in the seasonally hypoxic saline Lake Grevelingen, The Netherlands

Poster (2013, May 07)

Gardes à domicile : un aidant professionnel peu connu en Wallonie

Conference (2013, May 06)

Contexte : La garde à domicile est une professionnelle d’aide au maintien à domicile qui assure essentiellement une présence auprès du patient. Une étude menée en Belgique sur les équipes de soins ... [more ▼]

Contexte : La garde à domicile est une professionnelle d’aide au maintien à domicile qui assure essentiellement une présence auprès du patient. Une étude menée en Belgique sur les équipes de soins palliatifs à domicile visait à préciser le travail que ces professionnelles, mal connues des patients et des autres intervenants, effectuaient, les relations qu’elles tissaient avec les autres acteurs (professionnels comme patient et entourage familial) et les besoins qu’elles ressentaient dans le cadre des soins palliatifs. Méthode : 7 focus groups de professionnels ont été organisés. Deux comprenaient des infirmières, deux des coordinateurs de services de gardes à domicile et trois des gardes à domicile. Les entretiens ont été intégralement retranscrits et analysés, de manière thématique, par deux chercheurs indépendants. Résultats : Si les gardes à domicile sont des professionnelles formées à l’aide aux personnes, il n’existe pas de formation spécifique à la profession de garde à domicile. Leurs missions sont encore mal définies, allant de la présence auprès du patient à l’aide à la vie quotidienne. Les tâches ménagères sont exclues de leurs fonctions et les actes médicaux leur sont légalement défendus. Un de leurs souhaits est d’être formées, de manière spécifique, à l’accompagnement de patients palliatifs, tout en bénéficiant d’un meilleur soutien et d’un plus fort encadrement de la part de leurs services. C’est, en effet, un accompagnement vers la fin de vie, accompagnement difficile tant pour le patient que pour le personnel. Tout en augmentant leurs compétences, cela leur permettrait d’agir plus efficacement lorsque les autres professionnels ne sont pas disponibles, puisqu’elles sont appelées à travailler surtout la nuit et les week-ends. Elles souhaiteraient aussi que leur profession soit mieux reconnue et valorisée. Elles évoquent toute l’importance de leur présence pour assurer confort, écoute et surveillance du patient. Il est vrai que la famille mentionne souvent le coût de ce professionnel qui assure parfois seulement une présence et ne semble rien apporter de plus que ce que ne fait déjà la famille. Elles sont d’ailleurs appelées souvent tardivement lorsque les proches sont exténués. Les autres professionnels interrogés reconnaissent ignorer les missions précises des gardes à domicile ; certains nient leur utilité tandis que d’autres reconnaissent leur apport. Les gardes elles-mêmes se sentent dénigrées parfois par d’autres intervenants. La famille met en avant le soutien psychologique qu’elles apportent au patient et à l’entourage par leur présence. Discussion : La reconnaissance de ces professionnelles passe par plusieurs domaines. Il faut assurer une formation d’ensemble clairement définie ainsi que des formations plus spécifiques selon le type de travail qu’elles doivent effectuer. Une meilleure définition de leur travail devrait susciter des vocations pour un métier mieux ciblé et davantage reconnu. La diffusion de leur profil de travail ainsi qu’une meilleure information auprès des autres professionnels et des familles permettrait de mieux comprendre leur travail et de les appeler au bon moment. Perspectives : Réfléchir à un référentiel de compétences de ces professionnelles permettrait de créer un référentiel de formation qui, nous semble-t-il, devrait être centré sur les compétences communicationnelles. [less ▲]

Cadre d’analyse et d’évaluation des processus participatifs mis en œuvre dans le cadre de la gestion de l'environnement

Conference (2013, May 06)

Les années 1990 ont vu émerger une nouvelle façon d’appréhender le principe de participation : lors de l’élaboration d’un projet d’intérêt général par exemple, on institue une distinction entre l’intérêt ... [more ▼]

Les années 1990 ont vu émerger une nouvelle façon d’appréhender le principe de participation : lors de l’élaboration d’un projet d’intérêt général par exemple, on institue une distinction entre l’intérêt général du projet et l’intérêt général propre à la participation des citoyens à l’élaboration de la décision. Dans son rapport intitulé Global environment outlook 3 (Geo-3), le Programme des Nations Unies pour l’Environnement (PNUE) déclarait que « L'interaction créative d'individus et de groupes restreints fournit souvent des solutions efficaces permettant de gérer des situations complexes et variables ». On assiste alors à la multiplication des dispositifs de participation. Après deux décennies de pratique, les chercheurs et les praticiens de la participation commencent à établir le bilan des différents dispositifs participatifs. Pour faire ce bilan, certains adoptent une approche structurelle (la participation est alors considérée comme un phénomène dépendant des relations entre les acteurs), d’autres une approche processuelle qui s’intéresse davantage aux évolutions qui se produisent dans les interactions entre les acteurs au cours du processus participatif. Chacune de ces approches (structurelle et processuelle) est intéressante mais insuffisante pour avoir une vision complète de la réalité ; il est nécessaire de les croiser. Dans cette présentation, nous proposons un cadre d’analyse et d’évaluation qui, contrairement à la majorité des cadres d’analyses existants, associe l’approche structurelle à l’approche processuelle dans l’étude des processus participatifs. [less ▲]

Les papyrus scolaires grecs à contenu composite profane et chrétien (IIIe s. – VIIe s. de notre ère)

Conference (2013, May 03)

Documentée par des milliers de papyrus, – restes de livres ou de documents dont les plus anciens remontent au IIe siècle de notre ère –, la christianisation de l’Égypte a longtemps été perçue comme un ... [more ▼]

Documentée par des milliers de papyrus, – restes de livres ou de documents dont les plus anciens remontent au IIe siècle de notre ère –, la christianisation de l’Égypte a longtemps été perçue comme un phénomène ayant entraîné la disparition de la culture profane de tradition hellénique (paideia). Il faut cependant nuancer ce propos : nombre d’échanges, d’emprunts entre les deux types de cultures ont existé. Nous fondant sur l’analyse de la forme, de la mise en page et du contenu des 10 papyrus scolaires grecs et latins à contenu composite profane et chrétien (IIIe s. – VIIe s. de notre ère), nous montrerons comment la culture de tradition chrétienne et ses textes se sont intégrés à la paideia dans le cadre de l’enseignement en Égypte byzantine. [less ▲]

La gouvernance d’entreprise : outil pour améliorer la liquidité des titres

Conference (2013, May 02)

Based on a cross-sectional analysis, our study of the empirical relation between the corporate governance and the stock liquidity was realized on 160 French companies during 2007, 2008 and 2009. The ... [more ▼]

Based on a cross-sectional analysis, our study of the empirical relation between the corporate governance and the stock liquidity was realized on 160 French companies during 2007, 2008 and 2009. The handled mechanisms include the characteristics of the board of directors and the audit committee. Our results seem to indicate a significant effect of certain mechanisms of corporate governance on the liquidity of the French market. These mechanisms can reduce the asymmetry of information between the investors, make the exchanges more transparent and provoke an improvement of the liquidity on the market. These results suggest that firms with better corporate governance may reduce the informative asymmetry and improve the liquidity of its stocks. [less ▲]

Frequency-domain subspace identification of nonlinear mechanical systems

in Proceedings of the 5th International Operational Modal Analysis Conference (2013, May)

The objective of the present paper is to address the identification of a real-life strongly nonlinear space structure, the EADS-Astrium SmallSat spacecraft. To this end, a new nonlinear subspace ... [more ▼]

The objective of the present paper is to address the identification of a real-life strongly nonlinear space structure, the EADS-Astrium SmallSat spacecraft. To this end, a new nonlinear subspace identification method formulated in the frequency domain is exploited, referred to as the FNSI method. The frequency response functions of the underlying linear spacecraft and the amplitudes of the nonlinear internal forces are estimated based on a periodic-random data set corrupted by noise. This application is challenging for several reasons, including high modal density, highly non-proportional damping and the non-smooth nature of the nonlinearities. [less ▲]

Efficient database pruning for large-scale cover song recognition

in International Conference on Acoustics, Speech, and Signal Processing (ICASSP) (2013, May)

This paper focuses on cover song recognition over a large dataset, potentially containing millions of songs. At this time, the problem of cover song recognition is still challenging and only few methods ... [more ▼]

This paper focuses on cover song recognition over a large dataset, potentially containing millions of songs. At this time, the problem of cover song recognition is still challenging and only few methods have been proposed on large scale databases. We present an efficient method for quickly extracting a small subset from a large database in which a correspondence to an audio query should be found. We make use of fast rejectors based on independent audio features. Our method mixes independent rejectors together to build composite ones. We evaluate our system with the Million Song Dataset and we present composite rejectors offering a good trade-off between the percentage of pruning and the percentage of loss. [less ▲]

Lessons from the Liege Acromegaly Survey (LAS)

in Endocrine Abstracts - 15 the European Congress of Endocrinology (2013, May)

Is ultra-short cold ischemia the key to ischemic cholangiopathy avoidance in DCD-LT?

in Acta Chirurgica Belgica (2013, May), Supplement 113(3), 6729

Biogeochemistry and carbon mass balance of a coccolithophore bloom in the northern Bay of Biscay (June 2006)

Poster (2013, May)

Primary production (PP), calcification (CAL), bacterial production (BP) and dark community respiration (DCR) were measured along with a set of various biogeochemical variables, in early June 2006, at ... [more ▼]

Primary production (PP), calcification (CAL), bacterial production (BP) and dark community respiration (DCR) were measured along with a set of various biogeochemical variables, in early June 2006, at several stations at the shelf break of the northern Bay of Biscay. The cruise was carried out after the main spring diatom bloom that, based on the analysis of a time-series of remotely sensed chlorophyll-a (Chl-a), peaked in mid-April. Remotely sensed sea surface temperature (SST) indicated the occurrence of enhanced vertical mixing (due to internal tides) at the continental slope, while adjacent waters on the continental shelf were stratified, as confirmed by vertical profiles of temperature acquired during the cruise. The surface layer of the stratified water masses (on the continental shelf) was depleted of inorganic nutrients. Dissolved silicate (DSi) levels probably did not allow significant diatom development. We hypothesize that mixing at the continental slope allowed the injection of inorganic nutrients that triggered the blooming of mixed phytoplanktonic communities dominated by coccolithophores (Emiliania huxleyi) that were favoured with regards to diatoms due to the low DSi levels. Based on this conceptual frame, we used an indicator of vertical stratification to classify the different sampled stations, and to reconstruct the possible evolution of the bloom from the onset at the continental slope (triggered by vertical mixing) through its development as the water mass was advected on-shelf and stratified. We also established a carbon mass balance at each station by integrating in the photic layer PP, CAL and DCR. This allowed computation at each station of the contribution of PP, CAL and DCR to CO2 fluxes in the photic layer, and how they changed from one station to another along the sequence of bloom development (as traced by the stratification indicator). This also showed a shift from net autotrophy to net heterotrophy as the water mass aged (stratified), and suggested the importance of extracellular production of carbon to sustain the bacterial demand in the photic and aphotic layers. [less ▲]

Nonlinear guitar loudspeaker simulation

in Proceedings of the AES 134 th convention (2013, May)

Contact center as new forms of work organization: the triangular relationship between worker, contact center and contractors and well-being at work

Conference (2013, May)

Purpose The new forms of work organization are characterized by different evolutions: multiple workers status, fragmentation of collective work, etc. Among these evolutions, the triangular relationship ... [more ▼]

Purpose The new forms of work organization are characterized by different evolutions: multiple workers status, fragmentation of collective work, etc. Among these evolutions, the triangular relationship between worker, employer and contractors and the intervention of contractors in work organization (Marchington et al., 2004) may be particularly affecting the well-being of workers. This research focus on contact center as a new form of work organization to investigate the influence of the triangular employment relationship on well-being at work. Methodology A quantitative and qualitative approach was used. A survey based on Job Demand-Resources Model (Bakker, Demerouti & Schaufeli, 2003) was conducted among 400 operators from Belgian contact centers to compare internal, outsourced and external contact centers. Three case studies allowed exploring more deeply the influence of triangular employment relationship on well-being. Finally, focus-groups with unions and management representatives helped us to design some practical recommendations. Results Quantitative results indicate that operators from outsourced and external contact centers have a poorer perception of demands and resources at work. They are consequently more likely to report high levels of perceived stress and burnout and low satisfaction with their work. The case studies give us more information about the role of the strategy and the management style of contact centers in coping with triangular employment relationships. Limitations Beyond this explorative research, quantitative data can be further used in multi-sample modeling approach. Research/Practical Implications Recommendations for well-being at work regarding the triangular employment relationship, on which both employers and unions converge, will be highlighted at the conference. Originality This research combines organizational psychology and management theory. [less ▲]

Implementing sustainability strategies through accounting controls: An exploration of practices in seven multinational corporations

in Proceedings of the 36th Annual Congress of the European Accounting Association (EAA) (2013, May)

Holographic interferometry based on photorefractive crystal to measure 3D thermo-elastic distortion of composite structures and comparison with finite element models

in Lehmann, Peter (Ed.) Proc. SPIE Vol 8788 on Optical Measurement Systems for Industrial Inspection VIII (2013, May)

Thermo-elastic distortions of composite structures have been measured by a holographic camera using a BSO photorefractive crystal as the recording medium. The first test campaign (Phase 1) was performed ... [more ▼]

Thermo-elastic distortions of composite structures have been measured by a holographic camera using a BSO photorefractive crystal as the recording medium. The first test campaign (Phase 1) was performed on CFRP struts with titanium end-fittings glued to the tips of the strut. The samples were placed in a vacuum chamber. The holographic camera was located outside the chamber and configured with two illuminations to measure the relative out-of-plane and in-plane (in one direction) displacements. The second test campaign (Phase 2) was performed on a structure composed of a large Silicon Carbide base plate supported by 3 GFRP struts with glued Titanium end-fittings. Thermo-elastic distortions have been measured with the same holographic camera used in phase 1, but four illuminations, instead of two, have been used to provide the three components of displacement. This technique was specially developed and validated during the phase 2 in CSL laboratory. The system has been designed to measure an object size of typically 250x250 mm²; the measurement range is such that the sum of the largest relative displacements in the three measurement directions is maximum 20 μm. The validation of the four-illuminations technique led to measurement uncertainties of 120 nm for the relative in-plane and out-of-plane displacements, 230 nm for the absolute in-plane displacement and 400 nm for the absolute out-of-plane displacement. For both campaigns, the test results have been compared to the predictions obtained by finite element analyses and the correlation of these results was good [less ▲]

Comparison between Perkin-Elmer and Chromsytem Vitamin D kit on TQ 5500 from AB SCIEX

(2013, May)

Background: Twenty-five hydroxy-vitamin D (25(OH) D) determination is now routinely prescribed in the Laboratory. Recently, different new methods have been available for this determination. Among them ... [more ▼]

Background: Twenty-five hydroxy-vitamin D (25(OH) D) determination is now routinely prescribed in the Laboratory. Recently, different new methods have been available for this determination. Among them, LCMS/MS methods have emerged in some laboratories. However these methods are generally “home-brewed” and an important variability between them can be seen on different external quality controls, mainly due to a lack of standardization. Recently, Perkin-Elmer (PE) (Turku, Finland) and Chromsystem (CS) (Grafelfing, Germany) launched a standardised method for 25(OH )D determination on LCMS/MS. The aim of our study was to compare these methods on the AB SCIEX TQ5500 (Framingham, Massachusetts, USA) LCMS/MS to measure 25(OH) D3. Methods All the samples were treated according to our preanalyitical procedure: after sampling, they were spun at +4°c at 3500G, aliquoted and kept frozen at -20°c until determination. A method comparison was assessed with CS and PE for the measurement of the 25(OH)D3. We selected 110 remnant samples with 25(OH)D3 levels ranging from 1.6 to 136.7 ng/ml with the PE method to cover the range of usually values Slope and intercept were calculated using Passing and Bablock linear regression and we compared the methods with the Bland and Altman plots. Results For CS, the method is linear up to 250 µg/L, the LOQ is 3.6 µg/L, the intra-assay CV is < 5% and the inter-assay is < 7%. For PE, the method is linear up to 314 µg/L, the LOQ is 3.4 µg/L, the intra-assay CV is < 7.8% and the inter-assay is < 8.5%. On the whole range of measure (n=110), the regression equation is PE = 0.8521+0.9226 (CS) (95%CI of the intercept: (-0.0048;1.37) and 95% CI of the slope (0.89;0.95). The Bland and Altman plot does not show any bias between the two methods (mean difference CS-PE= -2.5 ng/ml) and the standard deviation of the mean is 3,98 ng/ml Conclusion: The performances of these methods are comparable on our new TQ 5500 from AB SCIEX. For now, there is no consensus on a “reference” method for vitamin D quantification. We notice only that the values obtained by CS are systematically a little bit lower than PE’s values, especially for results below 20 ng/ml. However, we have no clear explanation for such behaviour. [less ▲]

Digital Holographic Interferometry with CO2 Lasers Applied to Aspheric Space Reflectors Testing

Conference (2013, May)

Digital holographic interferometry at long infrared wavelengths allows monitoring large deformations of space reflectors during vacuum-thermal testing. We present different optical schemes and an ... [more ▼]

Digital holographic interferometry at long infrared wavelengths allows monitoring large deformations of space reflectors during vacuum-thermal testing. We present different optical schemes and an application to the complex case of elliptic reflector. [less ▲]

Study of interface trap density in a GeSn MOS structure by numerical simulation of the electrical characteristics

Conference (2013, May)

The semiconducting alloy germanium tin (GeSn) is expected to play an important role in the development of high mobility channel materials for next generation CMOS and optoelectronic devices. The two most ... [more ▼]

The semiconducting alloy germanium tin (GeSn) is expected to play an important role in the development of high mobility channel materials for next generation CMOS and optoelectronic devices. The two most interesting features of this material, which is compatible with mainstream Si technology, are its tunable direct band-gap and the possibility to induce strain due to the lattice mismatch with Ge and Si, thereby increasing the holes and electrons mobilities. It has been shown that the interface trap density can be under- or overestimated in Ge-channel MOSFETs when applying conventional measurement techniques such as the conductance method. As this effect is common in low band-gap materials, we expect that it also occurs for GeSn. Following our previous work on metal/GeSn/Ge structures, we have therefore applied our home-built numerical simulation software to a metal/oxide/GeSn MOS structure in order to investigate the result of the presence of such interface states. We discuss possible effects of the interface trap density, interface trap energy and temperature on the electrical characteristics. Successive simulations of both the steady-state and ac small-signal regimes give access to measurable quantities such as the admittance spectrum and the C-V curves. A physical interpretation can be attributed to their variations and an overall comparison can be made with results obtained from equivalent electrical circuit analysis. [less ▲]

La régulation par l'observation

Conference (2013, May)

La gestion durable des territoires: pratique multidisciplinaire émergente

Conference (2013, April 30)

Les projets SUN et SOLEN : Soutenir la régénération durable des quartiers.

Poster (2013, April 30)

Improvement of gluco-amylase B excretion by Aspergillus oryzae in a biofilm reactor

Poster (2013, April 29)

Héroïsation et Divinisation dans la Méditerranée Hellénistique : Introduction

Conference (2013, April 26)

‘Changer de microscope’ : Vers une analyse longitudinale des carrières politiques dans les systèmes multi-niveaux

Conference (2013, April 26)

Les modèles de carrière politique en Belgique, au Canada, en Espagne et au Royaume-Uni ont profondément évolué au cours des trois dernières décennies avec l’instauration des parlements régionaux et sous ... [more ▼]

Les modèles de carrière politique en Belgique, au Canada, en Espagne et au Royaume-Uni ont profondément évolué au cours des trois dernières décennies avec l’instauration des parlements régionaux et sous l’effet de leur professionnalisation. De récentes recherches ont démontré que, loin de constituer un simple tremplin vers le niveau national, le niveau subnational constitue une arène politique professionnelle à part entière. En nous basant sur une analyse longitudinale de l’ensemble des 2.450 carrières en Catalogne (n=1.044), en Écosse (n=368), au Québec (n=619) et en Wallonie (n=419) depuis l’instauration des parlements régionaux, nous démontrons tout d’abord que plusieurs modèles de carrière coexistent au sein d’une même région. Pour cela, un ‘changement de microscope’ est requis en utilisant les trajectoires individuelles comme unité d’analyse au lieu des seuls mouvements verticaux entre niveaux de pouvoirs. Enfin, nos résultats en ce qui concerne la variabilité interne des modèles (mesurée en fonction des partis politiques mais aussi du genre et de l’origine territoriale) invitent à des recherches complémentaires pour mieux comprendre les dynamiques de carrière, notamment dans leur dimension identitaire. Jusqu’alors considérée comme une variable explicative secondaire, cette dimension semble au contraire constituer une variable explicative de première ordre dans les quatre régions analysées. [less ▲]

À la limite de l’orthodoxie, aux confins de l’imperium christianum

Conference (2013, April 26)

Les allergies alimentaires : point de vue du biologiste

Conference (2013, April 25)

Return-To-Play criteria after hamstring injury: actual medicine practice in professional soccer

Poster (2013, April 25)

Time variyng groundwater flux measurement using a single well tracer technique

Poster (2013, April 24)

Contaminant mass discharge measurements are often performed at given times or integrated over a certain period of time, using active or passive sampling techniques. One problem arising is that such ... [more ▼]

Contaminant mass discharge measurements are often performed at given times or integrated over a certain period of time, using active or passive sampling techniques. One problem arising is that such measurements may not be representative of the temporal dynamics of the mass discharge variations. These variations can be caused by fluctuations in contaminant concentrations or, more frequently, by changes in the groundwater fluxes. Pollutant mass fluxes are typically estimated through a combination of solute concentrations and groundwater fluxes measured across a control plane made of several multi-level wells. Accurate measurements of local transient Darcy fluxes have been recognized as the weakest points in most of the developed techniques for groundwater contaminant mass flux measurements. The main objective here is to extend the FVPDM technique for temporal monitoring of groundwater fluxes and to demonstrate its ability to be used in combination with passive sampling devices for measurement of contaminant mass fluxes in groundwater. The Finite Volume Point Dilution Method (FVPDM) is a single well tracer technique for the measurement of local groundwater fluxes based on the continuous injection of tracer at very low injection rate (Brouyère et al. 2008). These developments are based on the application of the adapted technique on a case study in a fractured granitic aquifer in Ploemeur (France). This application investigates transient groundwater fluxes that are controlled by pumping in a well nearby the tested piezometers. Long monitoring time series have been recorded under these controlled conditions of transient groundwater flow. Results show the high sensivity of the FVPDM technique to small variations in groundwater flow velocities and its aptitude for long term monitoring of groundwater fluxes. The comparison between the results of FVPDM and classical point dilution tests performed in same conditions shows close correlation. Interpretation of FVPDM tests in transient conditions have been developed together with an evaluation of the uncertainties that can happen if the frequency of the groundwater flow variations is high. The tests carried on the Ploemeur site also illustrate the first ever application of the FVPDM technique between a double-packer system used for the investigation of a defined layer of an aquifer. This innovative application of the FVPDM using packers opens concrete perspectives for investigation of vertical heterogeneities of groundwater fluxes across a well. [less ▲]

Vocal loading profiles of kindergarten and elementary school teachers

Conference (2013, April 24)

Purpose: Although a global picture exists of teachers’ voice demands in general, few studies have compared specific groups of teachers to determine whether some are more at risk than others to develop ... [more ▼]

Purpose: Although a global picture exists of teachers’ voice demands in general, few studies have compared specific groups of teachers to determine whether some are more at risk than others to develop vocal loading related dysphonia. This study compared vocal loading of kindergarten and elementary school teachers; professional and non-professional vocal load was determined for both groups. Method: Twelve kindergarten and twenty elementary school female teachers were monitored during one workweek using the Ambulatory Phonation Monitor, Model 3200 (KayPENTAX). Vocal loading parameters analyzed were phonation time, F0, SPL, distance dose and cycle dose. A total of 160 days (≈1513 hours) of collected data were analyzed. Results and conclusions: All the parameters were higher for kindergarten teachers than for elementary school teachers in both professional and non-professional environments, but the differences were significant only for the cycle dose and the distance dose (p < .05). The higher vocal load measured in kindergarten teachers suggests that they could be more at risk for developing voice disorders than elementary school teachers. Particular attention should be paid to this specific group of teachers working with young children. Concerning the comparisons between professional and non-professional voice use, significant differences were observed for all parameters (p < .0001), indicating that vocal load was higher in the professional environment for both groups. [less ▲]

Characterization of the extracellular proteome of Escherichia coli according to the scale-up of bioprocesses and correlation with membrane permeability

Poster (2013, April 23)