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See detailMajor Changes in Growth Rate and Growth Variability of Beech (Fagus sylvatica L.) Related to Soil Alteration and Climate Change in Belgium
Latte, Nicolas ULg; Perin, Jérôme ULg; Kint, Vincent et al

in Forests (2016), 7(174),

Global change—particularly climate change, forest management, and atmospheric deposition—has significantly altered forest growing conditions in Europe. The influences of these changes on beech growth ... [more ▼]

Global change—particularly climate change, forest management, and atmospheric deposition—has significantly altered forest growing conditions in Europe. The influences of these changes on beech growth (Fagus sylvatica L.) were investigated for the past 80 years in Belgium, using non-linear mixed effects models on ring-width chronologies of 149 mature and dominant beech trees (87–186 years old). The effects of the developmental stage (i.e., increasing tree size) were filtered out in order to focus on time-dependent growth changes. Beech radial growth was divided into a low-frequency signal (=growth rate), mainly influenced by forest management and atmospheric deposition, and into a high-frequency variability (≈mean sensitivity), mainly influenced by climate change. Between 1930 and 2008, major long-term and time-dependent changes were highlighted. The beech growth rate has decreased by about 38% since the 1950–1960s, and growth variability has increased by about 45% since the 1970–1980s. Our results indicate that (1) before the 1980s, beech growth rate was not predominantly impacted by climate change but rather by soil alteration (i.e., soil compaction and/or nitrogen deposition); and (2) since the 1980s, climate change induced more frequent and intense yearly growth reductions that amplified the growth rate decrease. The highlighted changes were similar in the two ecoregions of Belgium, although more pronounced in the lowlands than in the uplands. [less ▲]

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See detailGreenland Ice sheet [in "State of the Climate in 2015"]
Tedesco, M.; Box, J.; Cappelen, J. et al

in Bulletin of the American Meteorological Society (2016), 97(8),

The Greenland Ice Sheet, with the capacity to contribute ~7 m to sea level rise, experienced melting over more than 50% of its surface for the first time since the record melt of 2012.

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See detailIntercomparison of in-situ NDIR and column FTIR measurements of CO2 at Jungfraujoch
Schibig, M. F.; Mahieu, Emmanuel ULg; Henne, S. et al

in Atmospheric Chemistry and Physics (2016), 16(15), 9935--9949

We compare two CO2 time series measured at the High Alpine Research Station Jungfraujoch, Switzerland (3580 m a.s.l.), in the period from 2005 to 2013 with an in situ surface measurement system using a ... [more ▼]

We compare two CO2 time series measured at the High Alpine Research Station Jungfraujoch, Switzerland (3580 m a.s.l.), in the period from 2005 to 2013 with an in situ surface measurement system using a nondispersive infrared analyzer (NDIR) and a ground-based remote sensing system using solar absorption Fourier transform infrared (FTIR) spectrometry. Although the two data sets show an absolute shift of about 13 ppm, the slopes of the annual CO2 increase are in good agreement within their uncertainties. They are 2.04±0.07 and 1.97±0.05 ppm yr-1 for the FTIR and the NDIR systems, respectively. The seasonality of the FTIR and the NDIR systems is 4.46±1.11 and 10.10±0.73 ppm, respectively. The difference is caused by a dampening of the CO2 signal with increasing altitude due to mixing processes. Whereas the minima of both data series occur in the middle of August, the maxima of the two data sets differ by about 10 weeks; the maximum of the FTIR measurements is in the middle of January, and the maximum of the NDIR measurements is found at the end of March. Sensitivity analyses revealed that the air masses measured by the NDIR system at the surface of Jungfraujoch are mainly influenced by central Europe, whereas the air masses measured by the FTIR system in the column above Jungfraujoch are influenced by regions as far west as the Caribbean and the USA. The correlation between the hourly averaged CO2 values of the NDIR system and the individual FTIR CO2 measurements is 0.820, which is very encouraging given the largely different sampling volumes. Further correlation analyses showed, that the correlation is mainly driven by the annual CO2 increase and to a lesser degree by the seasonality. Both systems are suitable to monitor the long-term CO2 increase, because this signal is represented in the whole atmosphere due to mixing. [less ▲]

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See detailIncentives and barriers to environmental inequality mobilization: A case-study analysis in Wallonia, Belgium
Lejeune, Zoé ULg; Teller, Jacques ULg

in Environmental Science and Policy (2016)

Environmental inequality scholarship has sought to shed light on the unequal environmental conditions borne by poor people and racial minorities, and to challenge public policies. Most studies are ... [more ▼]

Environmental inequality scholarship has sought to shed light on the unequal environmental conditions borne by poor people and racial minorities, and to challenge public policies. Most studies are concerned either with assessing the unequal distribution of environmental amenities and disamenities or with exploring the theoretical foundations of environmental justice movements. We propose an original approach to environmental inequality, focused not only on the unequal distribution of environmental burdens but also on two other types of factors: the capacity to mobilize and engage in community organizations on the one hand and the spatial dimension of environmental inequalities on the other. The evidence for this study is from an opinion survey carried out in 2012 with 1298 individuals. We use a two-step cluster analysis method to compute a classification system based on four categories of variables: socio-economic, environmental, spatial, and social capital. [less ▲]

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See detailAlternative electron transport to oxygen in green microalgae during induction and steady-state photosynthesis
Franck, Fabrice ULg; de Marchin, Thomas; Fratamico, Anthony ULg et al

Conference (2016, August 06)

In this study, we used combined fluorescence-based electron transport and oxygen measurements during steady-state photosynthesis to evaluate the responses to low and high CO2 in Chlamydomonas reinhardtii ... [more ▼]

In this study, we used combined fluorescence-based electron transport and oxygen measurements during steady-state photosynthesis to evaluate the responses to low and high CO2 in Chlamydomonas reinhardtii grown in photobioreactors at different light intensities. We present a method to quantify alternative electron transport to O2 from the relationship between the apparent quantum yields of oxygen evolution and of electron transport at PSII while taking into account the variations in the proportion of energy absorbed by PSII. We used this approach to evidence a significant O2-dependent alternative electron transport in low CO2 cells. We showed that this alternative electron transport represented up to 60% of the total electron transport in low CO2 cells even when the CO2 limitation had been removed by bicarbonate addition. In contrast, no significant alternative electron transport was detected in high CO2 cells. We also analysed alternative electron transport to O2 and its relationship with the fluorescence induction process during photosynthetic induction after dark-adaptation in several microalgal species. We show that a distinct sub-phase of the fluorescence decline after the fast OJIP rise is caused by alternative electron transport to O2 and is dependent on the pre-acclimatation of the cells to different CO2 supply conditions. The involvement of mitorespiration, chlororespiration and FLV proteins in alternative electron transport to O2 is discussed on the basis of results obtained with mutants, inhibitors and FLV protein expression. [less ▲]

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See detailLes limites de la papyrologie : papyrologie et enseignement universitaire
Marganne, Marie-Hélène ULg

Conference (2016, August 05)

Which dangers is Papyrology exposed to? How to overcome these obstacles? Assets. Disadvantages. Ideas for Solutions.

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See detailOn the effect of microstructural anisotropy on the mechanical and thermophysical properties of Ti6Al4V processed by Laser Beam Melting
Mertens, Anne ULg; Paydas, Hakan ULg; Rigo, Olivier et al

Conference (2016, August 05)

Laser beam melting (LBM) is a strongly directional process in which a metallic powder is deposited layer by layer in a powder bed and molten locally according to the desired shape. When processing Ti6Al4V ... [more ▼]

Laser beam melting (LBM) is a strongly directional process in which a metallic powder is deposited layer by layer in a powder bed and molten locally according to the desired shape. When processing Ti6Al4V, it is well known that the latest layer tends to solidify epitaxially on the previous layers, thus giving rise to elongated columnar primary β(BCC) crystals extending over several successive layers. These primary β grains then transforms into the α(HCP) structure upon cooling. The present work aimed at studying the microstructural anisotropy of LBM Ti6Al4V, as well as its consequences on the mechanical and thermophysical properties (i.e. thermal expansion and thermal conductivity). In order to gain a deeper undestanding of thermal phenomena in the LBM of Ti6Al4V, great care was also taken to characterize the thermophysical properties over a wide temperature range from room temperature. [less ▲]

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See detailPlaying RPG Maker? Amateur Game Design and Video Gaming
Hurel, Pierre-Yves ULg

Conference (2016, August 04)

Game creation tools like Game Maker or RPG Maker democratize game making and facilitate the development of amateur game design. The best known among these programs have dynamic web-communities with active ... [more ▼]

Game creation tools like Game Maker or RPG Maker democratize game making and facilitate the development of amateur game design. The best known among these programs have dynamic web-communities with active members making thousands of games. However, as of now, there is little research on amateur game design except for modding or education fields. In this paper I argue that approaching amateur game making in these relations with video game playing allows a better understanding of game creation tools’ users. To support my argument, I will lean on the early results of the exploratory step of my ongoing research. [less ▲]

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See detailThe np- Control Charts with the Guaranteed In-Control Performance
Faraz, Alireza ULg; Heuchenne, Cédric ULg

E-print/Working paper (2016)

In this paper, we evaluate the in-control performance of np-control charts with estimated parameters. We then apply the bootstrap method to adjust the control charts’ limits to guarantee the desired in ... [more ▼]

In this paper, we evaluate the in-control performance of np-control charts with estimated parameters. We then apply the bootstrap method to adjust the control charts’ limits to guarantee the desired in-control average run length (ARL0) value in monitoring stage. The adjusted limits ensure that ARL0 would take a value greater than the desired value (say, B) with a certain specified probability, that is Pr⁡(ARL_0>B)=1-ρ. We finally provide users with tables which with practitioners do not need to do bootstrapping Phase I data set to obtain the control limit thresholds. [less ▲]

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See detailLes rouleaux composites répertoriés dans le Catalogue des papyrus littéraires grecs et latins du CEDOPAL
Marganne, Marie-Hélène ULg

Conference (2016, August 04)

Les rouleaux littéraires composites préfigurent-ils les codices miscellanei tels que définis par Edoardo Crisci (Segno e Testo, 2, 2004, pp. 109-144) ? Après avoir examiné les quelques exemplaires ... [more ▼]

Les rouleaux littéraires composites préfigurent-ils les codices miscellanei tels que définis par Edoardo Crisci (Segno e Testo, 2, 2004, pp. 109-144) ? Après avoir examiné les quelques exemplaires répertoriés dans le Catalogue des papyrus littéraires grecs et latins du CEDOPAL (http://cipl93.philo.ulg.ac.be/Cedopal/MP3/dbsearch.aspx), leur nature, leur présentation et l'organisation de leur contenu, on s'est interrogé sur leur contexte de production et d'utilisation en vue de répondre à cette question. [less ▲]

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See detailETUDE DE FAISABILITE DU PROJET D’ECLAIRAGE PUBLIC PAR DES LAMPADAIRES SOLAIRES DU CAMPUS 2 DE L’UNIVERSITE DE DOUALA
Koagne Nkuate, Michael; Guembou Shouop, Cébastien Joel ULg; Djaowe, Samuel

Conference (2016, August 04)

Dans le cadre de sa politique énergétique et de promotion des énergies renouvelables, le Gouvernement Camerounais, à travers le Ministère de l’Eau et de l’Energie (MINEE), a fait appel à l’expertise des ... [more ▼]

Dans le cadre de sa politique énergétique et de promotion des énergies renouvelables, le Gouvernement Camerounais, à travers le Ministère de l’Eau et de l’Energie (MINEE), a fait appel à l’expertise des sociétés « Chinoise et vietnamienne (HUAWEI), en vue de le soutenir dans le programme du développement de son potentiel énergétique. Pourtant, un certain nombre d’entreprises locales (SINTEC 3D, K&M ENGINEERING, TECHNO CAMER …) s’intéressent de plus en plus à la valorisation et à la vulgarisation des énergies renouvelables. Pour ce faire, nous avons pensé à la proposition du savoir-faire, de la disponibilité locale d’une main d’œuvre qualifiée en matière d’électrification par énergie solaire. Ceci a l’endroit des institutions, des bailleurs de fond, des ONG ainsi qu’aux autorités étatiques Camerounaises. Nous avons ainsi travaillé sur des thèmes tels que : Modèle d’électrification rurale pour localités de moins de 1000 habitants l’extrême nord Cameroun ; méthode simple de calcul et de choix des équipements solaires pour une application domestique ; ainsi que sur le thème étude de faisabilité du projet d’éclairage public par des lampadaires solaires au campus 2 de l’université de douala. C’est ainsi qu’une mission d’étude s’est rendue au sein du Campus en janvier 2016. Les détails de cette mission sont présentés dans les annexes ci-jointes. Plusieurs objectifs sont lies à cette etude: éclairer les espaces (au sein du Campus 2 de l’université de Douala) allant de l’amphi Stanislas Melonné jusqu'à la faculté des sciences passant par l’ENSET et par l’amphi George Gango par des lampadaires solaires. Le projet permettra d’accroitre la disponibilité et la sécurité de l’approvisionnement en énergie tout en valorisant et en vulgarisant les énergies renouvelables (devenu de plus en plus incontournables). Ce projet a également pour but de promouvoir les nouvelles technologies pour un développement durable du Cameroun (programme mondial des énergies propres) et de faire valoir les ressources naturelles et humaines disponibles (soleil en permanence, jeunes ingénieurs de l’ISS,…). [less ▲]

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See detailTechniques et Méthodes nucléaires : Application de la Spectrométrie Gamma au Cameroun
Moyo N., Maurice; Kayo, Steve; Ngelem M., Eric J. et al

Poster (2016, August 04)

L’imaginaire populaire est de plus en plus pessimiste au sujet du mot nucléaire, utilisées selon eux, uniquement pour détruire, en cas de guerre. Une idée reçue, mais presque imposée par l'attitude des ... [more ▼]

L’imaginaire populaire est de plus en plus pessimiste au sujet du mot nucléaire, utilisées selon eux, uniquement pour détruire, en cas de guerre. Une idée reçue, mais presque imposée par l'attitude des pays développés qui donnent l'impression de recourir au nucléaire, le plus souvent, à des fins militaires. Pourtant, les applications du nucléaire sont utiles dans des domaines aussi variés que l'agriculture, la médecine, la détection des fuites dans les barrages, la surveillance de la qualité de l'air, des eaux, des sols, des matériaux de construction, des denrées alimentaires etc. Au Cameroun, l'utilisation des rayonnements ionisants (énergie nucléaire) est en pleine croissance. Ce, spécifiquement dans les domaines médical et industriel. La radioprotection est de plus en plus l’objet des recherches et des mesures au Cameroun. Des techniques d’analyse nucléaires sont également utilisées pour déterminer les risques radiologiques lies aux rayonnements naturels provenant de l’environnement. Dans ce cadre, l’unité de recherche « Physique Fondamentale » de l’université de Douala en collaboration avec l’ANRP (Agence Nationale de RadioProtection) utilise la spectrométrie gamma pour quantifier et qualifier l’exposition des camerounais aux rayonnements. Deux mémoires de master ont à cette occasion révéler le niveau d’exposition due aux rayonnements provenant du sol de l’Université de Douala d’une part et d’autre part l’exposition due aux matériaux de construction dans la ville de Douala. Les études sur les matériaux de construction (ciment utilisé dans la ville de Douala) ont permis d’observer que l’activité spécifique dans les échantillons de ciment varie d’un radionucléide à l’autre. L’estimation des paramètres radiologiques comme (l’activité du radium équivalent Raeq, l’indice du risque externe (Hex) et interne (Hin), le taux de dose absorbée dans l’air et la dose effective annuelle (AEDE) ont montré que l’utilisation comme matériaux de construction du ciment analysé était sans risque particulier. [less ▲]

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See detailINVESTIGATION OF 238U, 235U, 137CS AND 133XE IN SOILS FROM THE UNIVERSITY OF DOUALA-CAMEROON
Ndontchueng Moyo, Maurice; Guembou Shouop, Cébastien Joel ULg; Ngelem Mekontso, Eric Jilbert et al

Conference (2016, August 04)

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See detailEstimating the economic impact of a possible equine and human epidemic of West Nile virus infection in Belgium
Humblet, Marie-France ULg; Vandeputte, Sébastien; Fecher-Bourgeois, Fabienne ULg et al

in Eurosurveillance (2016), 21(31),

This study aimed at estimating, in a prospective scenario, the potential economic impact of a possible epidemic of WNV infection in Belgium, based on 2012 values for the equine and human health sectors ... [more ▼]

This study aimed at estimating, in a prospective scenario, the potential economic impact of a possible epidemic of WNV infection in Belgium, based on 2012 values for the equine and human health sectors, in order to increase preparedness and help decision-makers. Modelling of risk areas, based on the habitat suitable for Culex pipiens, the main vector of the virus, allowed us to determine equine and human populations at risk. Characteristics of the different clinical forms of the disease based on past epidemics in Europe allowed morbidity among horses and humans to be estimated. The main costs for the equine sector were vaccination and replacement value of dead or euthanised horses. The choice of the vaccination strategy would have important consequences in terms of cost. Vaccination of the country’s whole population of horses, based on a worst-case scenario, would cost more than EUR 30 million; for areas at risk, the cost would be around EUR 16–17 million. Regarding the impact on human health, short-term costs and socio-economic losses were estimated for patients who developed the neuroinvasive form of the disease, as no vaccine is available yet for humans. Hospital charges of around EUR 3,600 for a case of West Nile neuroinvasive disease and EUR 4,500 for a case of acute flaccid paralysis would be the major financial consequence of an epidemic of West Nile virus infection in humans in Belgium. [less ▲]

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See detailReplacement of Glycoprotein B in Alcelaphine Herpesvirus 1 by Its Ovine Herpesvirus 2 Homolog : Implications in Vaccine Development for Sheep-Associated Malignant Catarrhal Fever.
Cunha, Cristina W.; Taus, Naomi S.; Dewals, Benjamin G ULg et al

in mSphere (2016), 1(4), 00108-16

Vaccine development is a top priority in malignant catarrhal fever (MCF) research. In the case of sheep-associated MCF (SA-MCF) caused by ovine herpesvirus 2 (OvHV-2), progress toward this objective has ... [more ▼]

Vaccine development is a top priority in malignant catarrhal fever (MCF) research. In the case of sheep-associated MCF (SA-MCF) caused by ovine herpesvirus 2 (OvHV-2), progress toward this objective has been hindered by the absence of methods to attenuate or modify the virus, since it cannot be propagated in vitro. As an alternative for vaccine development, in this study, we tested the hypothesis that one of the SA-MCF vaccine candidate targets, OvHV-2 glycoprotein B (gB), could be expressed by a nonpathogenic alcelaphine herpesvirus 1 (AlHV-1) and then evaluated the potential of the AlHV-1/OvHV-2 chimera to be used as a vaccine and a diagnostic tool. The construction and characterization of an AlHV-1/OvHV-2 chimeric virus that is nonpathogenic and expresses an OvHV-2 vaccine target are significant steps toward the development of an SA-MCF vaccine and also provide a valuable means to study OvHV-2 biology. [less ▲]

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See detailAssessment of the sea-ice carbon pump: Insights from a three-dimensional ocean-sea-ice biogeochemical model (NEMO-LIM-PISCES)
Moreau, Sébastien; Vancoppenolle, Martin; Bopp, Laurent et al

in Elementa: Science of the Anthropocene (2016), 4(1), 000122

The role of sea ice in the carbon cycle is minimally represented in current Earth System Models (ESMs). Among potentially important flaws, mentioned by several authors and generally overlooked during ESM ... [more ▼]

The role of sea ice in the carbon cycle is minimally represented in current Earth System Models (ESMs). Among potentially important flaws, mentioned by several authors and generally overlooked during ESM design, is the link between sea-ice growth and melt and oceanic dissolved inorganic carbon (DIC) and total alkalinity (TA). Here we investigate whether this link is indeed an important feature of the marine carbon cycle misrepresented in ESMs. We use an ocean general circulation model (NEMO-LIM-PISCES) with sea-ice and marine carbon cycle components, forced by atmospheric reanalyses, adding a first-order representation of DIC and TA storage and release in/from sea ice. Our results suggest that DIC rejection during sea-ice growth releases several hundred Tg C yr−1 to the surface ocean, of which < 2% is exported to depth, leading to a notable but weak redistribution of DIC towards deep polar basins. Active carbon processes (mainly CaCO3 precipitation but also ice-atmosphere CO2 fluxes and net community production) increasing the TA/DIC ratio in sea-ice modified ocean-atmosphere CO2 fluxes by a few Tg C yr−1 in the sea-ice zone, with specific hemispheric effects: DIC content of the Arctic basin decreased but DIC content of the Southern Ocean increased. For the global ocean, DIC content increased by 4 Tg C yr−1 or 2 Pg C after 500 years of model run. The simulated numbers are generally small compared to the present-day global ocean annual CO2 sink (2.6 ± 0.5 Pg C yr−1 ). However, sea-ice carbon processes seem important at regional scales as they act significantly on DIC redistribution within and outside polar basins. The efficiency of carbon export to depth depends on the representation of surface-subsurface exchanges and their relationship with sea ice, and could differ substantially if a higher resolution or different ocean model were used. [less ▲]

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See detailFrom practice-based game research to game design as a cultural technique
Werning, Stefan; Kamp, Michiel; De Smale, Stephanie et al

Conference (2016, August 02)

Panel : de Smale, Stephanie: Game Essays in the Digital Humanities : The paper addresses the use of prototyping for creating game essays, the applicability of game essays within a digital humanities ... [more ▼]

Panel : de Smale, Stephanie: Game Essays in the Digital Humanities : The paper addresses the use of prototyping for creating game essays, the applicability of game essays within a digital humanities framework and the challenges and opportunities of taking a research-centric rather than a player-centric perspective on game design. Kamp, Michiel: Parameters of Musical Interaction in Games : The paper proposes exploring game music by experimenting with the ways in which the soundtrack responds to game states and player interaction beyond adapting analytical techniques borrowed from film music studies, like masking or replacing parts of the soundtrack. Hurel, Pierre-Yves: Amateur Game Design as Reflexive Practice : The paper presents an ethnographic perspective on amateur game design with a particular focus on the use of distinct tools such as RPG Maker and their affordances for reflective practice. Werning, Stefan: From Analytical Play to Analytical Game Design : The paper outlines the transition from intrinsically analytical aspects in (meta-)ludic practices (speed-running, in-game photography, cosplaying, let’s playing etc.) to game design as a cultural technique, i.e. a mode of expression and civic engagement in a gamified society. [less ▲]

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