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See detailPast changes in the vertical distribution of ozone – Part 3: Analysis and interpretation of trends
Harris, N. R. P.; Hassler, B.; Tummon, F. et al

in Atmospheric Chemistry and Physics (2015), 15(17), 9965--9982

Trends in the vertical distribution of ozone are reported and compared for a number of new and recently revised data sets. The amount of ozone-depleting compounds in the stratosphere (as measured by ... [more ▼]

Trends in the vertical distribution of ozone are reported and compared for a number of new and recently revised data sets. The amount of ozone-depleting compounds in the stratosphere (as measured by equivalent effective stratospheric chlorine – EESC) was maximised in the second half of the 1990s. We examine the periods before and after the peak to see if any change in trend is discernible in the ozone record that might be attributable to a change in the EESC trend, though no attribution is attempted. Prior to 1998, trends in the upper stratosphere (~45 km, 4 hPa) are found to be -5 to -10% per decade at mid-latitudes and closer to -5% per decade in the tropics. No trends are found in the mid-stratosphere (28 km, 30 hPa). Negative trends are seen in the lower stratosphere at mid-latitudes in both hemispheres and in the deep tropics. However, it is hard to be categorical about the trends in the lower stratosphere for three reasons: (i) there are fewer measurements, (ii) the data quality is poorer, and (iii) the measurements in the 1990s are perturbed by aerosols from the Mt Pinatubo eruption in 1991. These findings are similar to those reported previously even though the measurements for the main satellite and groundbased records have been revised. There is no sign of a continued negative trend in the upper stratosphere since 1998: instead there is a hint of an average positive trend of ~2% per decade in mid-latitudes and ~3% per decade in the tropics. The significance of these upward trends is investigated using different assumptions of the independence of the trend estimates found from different data sets. The averaged upward trends are significant if the trends derived from various data sets are assumed to be independent (as in Pawson et al., 2014) but are generally not significant if the trends are not independent. This occurs because many of the underlying measurement records are used in more than one merged data set. At this point it is not possible to say which assumption is best. Including an estimate of the drift of the overall ozone observing system decreases the significance of the trends. The significance will become clearer as (i) more years are added to the observational record, (ii) further improvements are made to the historic ozone record (e.g. through algorithm development), and (iii) the data merging techniques are refined, particularly through a more rigorous treatment of uncertainties. [less ▲]

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See detailImmunoglobulin E enhances host resistance to venoms.
Marichal, Thomas ULg

Conference (2015, September 07)

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See detailDiasporic Experience and Music in Caryl Phillips’s Crossing the River
Mascoli, Giulia ULg

Conference (2015, September 07)

This paper deals with Caryl Phillips who has incessantly represented diasporic experience in his work where he evokes complex identities at the crossroads between Africa, the Caribbean and Europe. My ... [more ▼]

This paper deals with Caryl Phillips who has incessantly represented diasporic experience in his work where he evokes complex identities at the crossroads between Africa, the Caribbean and Europe. My proposal is to concentrate on Phillips’s novel Crossing the River (1993) which extensively explores the theme of the African diaspora and which, interestingly, has also been described as his most jazzy text. This narrative not only addresses diasporic themes, such as uprootings and lost origins, but very much like jazz -- which is for Brathwaite “a cry from the heart of the hurt man” (277) – it gives a voice to the victims of history, to shattered individuals in pain whose tragic fate is viewed at once as personal and collective. Benítez-Rojo draws attention to the importance of rhythm in this text, but he only provides a limited analysis with no specific examples of how this significant feature of the work is achieved or the purposes it serves. In this paper I will try to demonstrate that Phillips’s thematic and formal use of music, including the references to classic themes of the African American musical tradition or the recurrent and creative use of repetitions, has a performative role and reenacts the duty of remembering inherent in the diasporic experience. [less ▲]

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See detailCitizens abroad and Regional Elections: A diffusionist Perspective
Lafleur, Jean-Michel ULg; Arrighi, Jean-Thomas

Conference (2015, September 06)

In this paper we shift the focus away from the state to the regional demos with the aim to introduce the notion of scale in the study of external voting. It is divided into three parts. Following a ... [more ▼]

In this paper we shift the focus away from the state to the regional demos with the aim to introduce the notion of scale in the study of external voting. It is divided into three parts. Following a preliminary discussion on the external franchise from a sub-state perspective, we proceed with a comparative overview of the rules of acquisition and loss of the franchise in regional elections and show that the extension of the franchise to ‘regional expatriates’ is a relatively exceptional practice. We then identify factors that in our view are key to understand the absence of a vertical diffusion of the external franchise to lower levels of government, in sharp contrast with its rapid horizontal diffusion at the state level. The second part examines the debates surrounding the inclusion and exclusion of the franchise in three cases of protracted nationalist mobilization that translated into far reaching territorial autonomy: Catalonia, Scotland and Flanders. The third and final section contrasts the similarities and differences that can be found between our three cases and reflects upon the lessons that can be drawn from them. [less ▲]

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See detailBinge Drinking at young age
Gavray, Claire ULg

Conference (2015, September 05)

discussion théorique et méthodologique sur le concept et la mesure du binge drinking. Présentation des facteurs liés à cette pratique chez les adolescents filles et garçons. Analyse des résultats à la ... [more ▼]

discussion théorique et méthodologique sur le concept et la mesure du binge drinking. Présentation des facteurs liés à cette pratique chez les adolescents filles et garçons. Analyse des résultats à la lumière des opportunités historiques sexuées en évolution.données ISRD3-Belgique [less ▲]

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See detailAb-initio study of thermoelectricity of layered tellurium compounds
Ibarra Hernández, Wilfredo ULg

Doctoral thesis (2015)

In this thesis, we explore the electronic, dynamic and thermoelectric properties of different tellurium-based compounds. We perform ab-initio calculations within the Vienna Ab-initio Simulation Package ... [more ▼]

In this thesis, we explore the electronic, dynamic and thermoelectric properties of different tellurium-based compounds. We perform ab-initio calculations within the Vienna Ab-initio Simulation Package (VASP) that works in the framework of Density Functional Theory (DFT). For the thermoelectric properties, we use the Boltztrap code that solves the Boltzmann Transport Equations (BTE) for electrons within the Constant Relaxation Time Approximation (CRTA). This computational package allows us to obtain accurate values of the Seebeck coefficient as a function of temperature and carrier concentration (this last with the help of the rigid band approximation). While for the calculation of the lattice contribution to the thermal conductivity, we use the ShengBTE code that solves the BTE for phonons iteratively. The first tellurium-based compound that we study is the best room temperature thermoelectric material, Bi2Te3. We obtain results comparable with experimental data for the Seebeck coefficient at room temperature and pressure. Afterwards, we proceed to explore the evolution of the electronic properties and the thermoelectric performance under pressures up to 5 GPa. We reproduce the overall trend of the Seebeck coefficient as a function of pressure for two different values of doping, however, our results do not reproduce the small improvement found in experiments close to 1 GPa. Nevertheless, we support the experimental evidence of an Electronic Topological Transition (ETT) around 2 GPa and we explain this particular behavior. We also perform calculations on the tellurium-based phase-change materials (GeTe)x(Sb2Te3)1 (with x = 1, 2, 3). We show results for different stacking configurations since for some compositions, the stacking arrangement of the atoms in the primitive cell is still unsettled. We find that the change of the atomic arrangement leads to the systems to go from semiconductors to metals. We find that the semiconductor arrangements systematically overestimate the experimental values for the Seebeck coefficient, whereas the metallic stacking sequences are in very good agreement with the experimental data for the Seebeck coefficient and for the lattice contribution to the thermal conductivity. We show that (GeTe)x(Sb2Te3)1 materials could reach values of ZT=0.5 around 600 K with a proper optimization of S with respect to the carrier concentration. We also report that in the case of x=3, the most accepted stacking configuration is dynamically unstable, therefore we proposed another sequence. Finally, we discuss the discrepancies between our work and recent theoretical reports that claim the existence of a Dirac-cone like band structure for (GeTe)2(Sb2Te3)1. We explain the conditions necessary to obtain such electronic topology. [less ▲]

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See detailEVALUATION OF SV2Alox/Cre TRANSGENIC MOUSE USING [18F]UCB-H IN IN VITRO AUTORADIOGRAPHY
Serrano Navacerrada, Maria Elisa ULg; Becker, Guillaume ULg; MENTEN, Catherine ULg et al

Poster (2015, September 04)

Background: SV2A is the most studied isoform of the Synaptic Vesicle 2 proteins, which are involved in the synaptic vesicle trafficking. Interestingly, the SV2A has been identify as the binding site for ... [more ▼]

Background: SV2A is the most studied isoform of the Synaptic Vesicle 2 proteins, which are involved in the synaptic vesicle trafficking. Interestingly, the SV2A has been identify as the binding site for the antiepileptic drug levetiracetam, showing a close relation between the epilepsy, the dysregulation of the SV2A levels and the response to antiepileptic medications. SV2A floxed-mice were developed using a cre-lox technique, leading to a strong decrease of SV2A expression in the CA3 field of the hippocampus. We aim here to validate this model using [18F]UCB-H, a novel PET imaging radiotracer with a nanomolar affinity for human SV2A. Methods: In vitro autoradiography were performed on SV2Alox/Cre+ transgenic mouse brain slices. SV2Alox/Cre- mouse was used as control. To obtain a structural reference, brain slices underwent eosin-haematoxylin staining. Images of both procedures were coregistered using π-PMOD software. Regions of interest (Dentate Gyrus, CA1, CA2 and CA3) were drawn according to a stereotaxic atlas of the mouse brain. Results: Analyses showed significant differences in radiotracer binding (p<0.001) between SV2Alox/Cre+ mouse and SV2Alox/Cre- mouse highlighting an important reduction for the labelling density in Ammon's horn, particularly in CA1, compared to Dentate Gyrus where the diminution was less marked. Conclusions: Here, we used the radiotracer [18F]UCB-H to probe the decreased expression of SV2A protein in the hippocampus of SV2Alox/Cre+ mouse versus SV2Alox/Cre- control mouse. Our results contribute to the validation of the model, and encourage us to proceed with further longitudinal and behavioural studies. [less ▲]

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See detailL'agame-papillon géant, Leiolepis guttata (Cuvier, 1829), dans la province de Binh Thuan, Vietnam : biologie, écologie, alimentation, enjeux économiques et gestion d'élevage
Tran, Tinh ULg

Doctoral thesis (2015)

Nous avons d'abord considéré la viande et les oeufs de lézard pour la consommation humaine à travers le monde. Nous démontrons l'importance de cette ressource comme source de nourriture humaine de bonne ... [more ▼]

Nous avons d'abord considéré la viande et les oeufs de lézard pour la consommation humaine à travers le monde. Nous démontrons l'importance de cette ressource comme source de nourriture humaine de bonne qualité. Suite à l’apparition en 2004 des premiers élevages de Leiolepis gutatta, l’agame-papillon géant, dans la province côtière de Binh Thuan, aux succès qui s’ensuivirent et à leur importance pour les petits paysans de cette région semi-désertique où les productions agricoles sont extrêmement limitées à cause du climat et du sol, cette espèce a été choisie pour nos recherches. Notre étude vise à disposer de meilleures connaissances de Leiolepis guttata concernant sa biologie, son écologie, son alimentation et ses enjeux économiques, le tout débouchant sur une meilleure gestion de l’élevage. Nous envisageons en premier lieu sa distribution, son milieu de vie naturel, les types de formations végétales et les écosystèmes où il s’observe. Le climatope, l’édaphotope et les phytocénoses concernées ont été étudiés et définis. Un herbier de référence (MRT) a été constitué et un CD réalisé. L’alimentation constitue le thème suivant. Il s’appuie sur des observations préliminaires concernant le tractus digestif de l’agame-papillon ; les fractions végétales, animales et minérales observées dans les estomacs sont étudiées ; des enquêtes auprès des éleveurs ont été menées afin de recueillir des informations sur les aliments (essentiellement les végétaux) consommés par ce lézard. Au cours de ce travail, nous avons montré que Leiolepis guttata était un lézard essentiellement herbivore à même de consommer et de digérer un très grand nombre de végétaux en fonction des opportunités et disponibilités alimentaires. Nous avons approché la diversité alimentaire tant en milieu naturel qu’en élevage (116 produits différents, dont 91 relèvent du règne végétal et 22 du règne animal). La composition chimique de 71 plantes et 4 insectes a été déterminée. Nos observations ont également mis en évidence la présence importante de vers parasites (Oxyuridae notamment). Le nombre d’élevages de Leiolepis guttata dans la province de Binh Thuan a considérablement augmenté entre 2007 et 2013 afin de satisfaire une demande forte de ces reptiles soit pour la consommation de viande très prisée dans cette région touristique, soit comme reproducteurs ; par contre après avoir atteint des valeurs très élevées, les prix de vente sont en diminution depuis ces toutes dernières années : l’offre dépassant la demande. Si l’élevage s’est développé, c’est de façon anarchique, sans connaissances techniques de la part des éleveurs, mais surtout par échange d’expériences entre eux. Les enclos d’élevage, leur aménagement et l’achat des reproducteurs constituent un point important pour la réussite de ce type d’élevage. Notre travail apporte donc des informations sur les principaux avantages et inconvénients des types d'enclos actuels. Ensuite, nous formulons des recommandations pour la construction et l'aménagement d'enclos d'élevage adaptés aux conditions locales en ce compris une étude des coûts et revenus. Parallèlement au développement des élevages, on constate également une très forte régression de l’espèce dans le milieu naturel de plus en plus dégradé suite au développement des infrastructures routières et touristiques de la région. En conclusion, si l’élevage en captivité de Leiolepis guttata peut contribuer au maintien de l’espèce dans cette région, la durabilité de la production pour les éleveurs nécessite qu’ils acquièrent de meilleurs connaissances techniques quant à la biologie, l’écologie, l’alimentation et la gestion de l’élevage sans nécessairement rechercher des solutions techniquement optimales souvent coûteuses et non rentables pour ce genre de production. A l’avenir, une attention particulière devrait être apportée aux besoins nutritionnels en fonction des stades physiologiques, aux aspects génétiques (consanguinité) et aux risques de maladies liées à ces élevages en forte densité. Enfin, une régulation entre l’offre et la demande doit impérativement être recherchée. [less ▲]

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See detailMagnetic shielding properties of tubular bulk superconductors subjected to stray magnetic fields
Hogan, Kevin ULg; Fagnard, Jean-François ULg; Wera, Laurent ULg et al

Conference (2015, September 04)

Superconducting materials act as efficient magnetic shields thanks to their intrinsic magnetic properties. The vast majority of studies on superconducting shields has been conducted in homogeneous ... [more ▼]

Superconducting materials act as efficient magnetic shields thanks to their intrinsic magnetic properties. The vast majority of studies on superconducting shields has been conducted in homogeneous magnetic field configurations. Only few works have been done concerning inhomogeneous magnetic field configurations while those are representative of practical situations. Moreover, those configurations are non-trivial given the magnetic hysteretic behaviour of type-II superconductors. In the present work, we aim at investigating and understanding the magnetic response of a superconducting hollow cylinder made of Bi-2223 subjected to the magnetic stray field of various magnetic sources. Thanks to a bespoke 3D mapping system and a three-axis Hall probe, we measure the magnetic flux density distribution in the vicinity of the cylinder when the latter is subjected to those stray fields. All experiments are carried out in liquid nitrogen. Our experimental data allow us to apprehend the magnetic field penetration inside the superconductor in inhomogeneous field configurations and to compare those to results obtained with homogeneous fields. Then we compare our results to a finite element model of an infinite tube subjected to an inhomogeneous magnetic field in order to gather information on the magnetic field penetration and the current density distribution inside the superconductor. [less ▲]

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See detailFrom Aleph to Alma: Fulfillment, feel it fully
Van Ruymbeke, Muriel ULg; Lhoest, Rémy ULg; Thirion, Paul ULg

Conference (2015, September 04)

If it is well prepared, migrating from Aleph to Alma brings users a lot of advantages. To reach the go live day with as less worries as possible, ULg Library's preparation consisted in two things: a deep ... [more ▼]

If it is well prepared, migrating from Aleph to Alma brings users a lot of advantages. To reach the go live day with as less worries as possible, ULg Library's preparation consisted in two things: a deep understanding of Alma new concepts and a simplification of our physical fulfillment policy. This presentation, based on our experience, will aim at describing the main differences between Aleph and Alma regarding fulfillment concepts and their significant consequences on implementation and migration jobs. On a fulfillment point of view, what distinguishes Aleph from Alma is that, in Aleph, the circulation policy is based on item status. On the contrary in Alma it is based on the location, and its traffic rules built by a set of terms of uses (TOU). Numerous other idioms complete the Alma toolkit and allow physical item’s fulfillment customizing. But to really enjoy the new possibilities given by Alma, it is important to fully feel the necessary changes… at the very beginning ! [less ▲]

Detailed reference viewed: 53 (4 ULg)
See detailWill Big Data Deliver its Promised Productivity Growth?
Artige, Lionel ULg

E-print/Working paper (2015)

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See detailLes carrières en fin d'activités: un potentiel paysager?
Joris, Alicia ULg

Master's dissertation (2015)

The present study focuses on the landscape concept and evaluations and is based on some issues related to the impact, restoration and ecological potential of the abandoned quarries. It proposes a ... [more ▼]

The present study focuses on the landscape concept and evaluations and is based on some issues related to the impact, restoration and ecological potential of the abandoned quarries. It proposes a landscape character assessment for non active limestone quarries resulting from the spontaneous succession. Taking into account the guidelines of the European Landscape Convention (Conseil de l'Europe, 2000) , this work has for objectives (1) to describe these landscape areas and (2) to assess the landscape aesthetic quality. To achieve these goals, two methods inspired by the Landscape Character Assessment (LCA) were tested. The first one is a field sheet and the second one a landscape perception survey with stakeholders. The results have emphasized the natural, harmonious and unique character of these landscapes. The key characteristics are the visual importance of cliffs, water bodies, vegetation forms and the landform in bleachers. Furthermore, color contrast and textures from vegetation, rock and water were also relevant. An apparent aesthetic landscape quality was perceived and the study showed that respondents are feeling good in the site surveyed. The quarryscape can be characterized of challenging, attractive, wild with an important degree of naturality but not really safe. Cultural, historic, symbolic and ecological values were also highlighted as a potential. These later observations take part in a landscape dynamic and allow to open the debate concerning the need for landscape interventions within these sites and the profit we could benefit from if security issues were well-managed. [less ▲]

Detailed reference viewed: 29 (5 ULg)
Peer Reviewed
See detailThe impact of ageing on episodic memory encoding: an fMRI study
François, Sarah ULg; Angel, Lucie; SALMON, Eric ULg et al

Poster (2015, September 04)

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See detailSelf-Reported Delinquency Survey: Comparison of Two Methods Among Female and Male Detained Adolescents
Grégoire, Julie ULg; Mathys, Cécile ULg

Poster (2015, September 04)

Self-report delinquency (SRD) surveys have begun to be used more than 70 years ago to measure delinquency (Porterfield, 1943). Since then, lots of methods have been developed (e.g. P&P questionnaire ... [more ▼]

Self-report delinquency (SRD) surveys have begun to be used more than 70 years ago to measure delinquency (Porterfield, 1943). Since then, lots of methods have been developed (e.g. P&P questionnaire, telephone interviewing, face-to-face interviewing, CASI, ACASI) for data collection (Kleck & Roberts, 2012). Although a lot of researches have assessed the participation rates of these methods, most of SRD surveys are submitted to non-detained adolescents . We have therefore noticed that those methods only allow us to know but little about the participation rate of young detainees and about their motivation to take part in a SRD survey. This research, which constitutes the pre-test of a further larger research, aims to: 1) Identify which method of SRD (comparing Paper & Pencil (P&P) questionnaire and Web questionnaire) has the highest participation rate and is the most attractive for young detained people, and if there are differences between boys and girls. 2) Determine the impact of an incentive on the motivation to participate in a survey, and if there are differences between boys and girls. As a result, we can observe that the SRD survey method doesn’t seem to have an influence on the participation rate of youth from detention centers. Nevertheless, the most attractive SRD survey method seems to be the Web one. As it is also less discouraging, it seems preferable to use this method with these adolescents whenever it is possible. Regarding the different kinds of incentives regularly used in research, their impact on the decision to take part in a survey turns out to be very weak, even nonexistent or negative. It appears that an incentive for juveniles placed in detention centers is inappropriate to increase their motivation to participate. [less ▲]

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See detailAge-related modulations in cognitive functions and its cerebral underpinnings
Collette, Fabienne ULg

Conference (2015, September 04)

Detailed reference viewed: 14 (1 ULg)
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See detailCopy number variants in patients with intellectual disability affect the regulation of ARX transcription factor gene
ishibashi, Minaka; Manning, Elisabeth; Shoubridge, Cheryl et al

in Human Genetics (2015), 134

Detailed reference viewed: 10 (0 ULg)
See detailSeasonality in human cognitive brain responses.
Meyer, Christelle ULg; Muto, Vincenzo ULg; Jaspar, Mathieu ULg et al

Poster (2015, September 04)

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See detailTrend analysis in ecological status and macrophytic characterization of watercourses: case of the Semois-Chiers basin, Belgium Wallonia
Sossey Alaoui, Khadija ULg; Rosillon, Francis ULg; Tychon, Bernard ULg

in Journal of Water Resource and Protection (2015), Vol.7 No.13 2015

In order to analyze the distribution and evolution of the aquatic vegetation and ecological status of the Semois-Chiers basin (Semois sub-basin and Chiers sub-basin), macrophyte surveys were conducted at ... [more ▼]

In order to analyze the distribution and evolution of the aquatic vegetation and ecological status of the Semois-Chiers basin (Semois sub-basin and Chiers sub-basin), macrophyte surveys were conducted at 48 sites in 2007 and 2013. Environmental parameters were also measured in order to characterize the waterbodies in terms of physico-chemical properties and anthropogenic pressure. The two-way clustering and indicator value (INDVAL) methods were used to assess groups of sites according to their macrophytic composition and species communities. The results showed a clear difference between streams in the Lorraine area (calcareous watercourses) and in the Ardennes (siliceous). Within each natural region, those with natural vegetation of high ecological status were separated from those dominated by resistant species. The Macrophytical Biological Index for Rivers (IBMR), was calculated for the sites visited in 2010 and 2013 and the results show a trend towards an increase of IBMR values of polluted sites. For the latter, the Wilcoxon test was performed to assess the significance of the difference in quality between 2010 and 2013. This showed a statistically significant difference (p-value= 0.035). Our results showed similarities with previous data, as well as some differences. The differences observed might indicate a gradual change in the composition of the vegetation in the study area, caused by changes in environmental conditions. They could also reflect a lack of information about the ecology of certain groups of plants, mainly bryophytes and macroalgae that were not considered in previous studies. Despite the measures implemented under the EU’s Water Framework Directive (WFD), the current vegetation of the Semois river differs little from that observed in 1996. There is a slight improvement in the headwaters of a Semois river, described in previous studies as polytrophic and devoid of vegetation, with the appearance of macrophytic species. In some parts of the Chiers sub-basin, however, resistant species observed in 1999 persist. [less ▲]

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