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See detailDo large companies ignore formal sustainability management controls? An exploration amongst corporate practices
Crutzen, Nathalie ULg; Schaltegger, Stefan

in EMAN (Ed.) Proceedings of the 2014 EMAN conference (2014, March)

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See detailLong-term outcome and use of 6-Minute Walk test in West Highland white Terriers with idiopathic pulmonary fibrosis
Lilja-Maula, LIO; Laurila, HP; Syrjä, P et al

in Journal of Veterinary Internal Medicine (2014), 28(2), 379-385

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See detailJeux vidéo : l'heure de la démocratisation ?
Hurel, Pierre-Yves ULg

Article for general public (2014)

Article faisant le parallèle entre l'arrivée de la super 8, qui démocratisa les pratiques amateurs de vidéastes, et la convergence de travaux et de logiciels facilitant la programmation de jeux vidéo.

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See detailDe rol van de bibliotheek in tijden van information overload
Decoster, Sara ULg

in Cahiers de la Documentation = Bladen voor Documentatie (2014, March), 68(1),

Cet article étudie le rôle que peut jouer la bibliothèque en temps d’information overload et part des deux composantes de base du phénomène de l’infobésité : en premier lieu, un flot de données ... [more ▼]

Cet article étudie le rôle que peut jouer la bibliothèque en temps d’information overload et part des deux composantes de base du phénomène de l’infobésité : en premier lieu, un flot de données objectivement important, et, en second lieu, la manière dont ces données sont traitées par le sujet humain, l’usager. Pour gérer l’afflux de données constant, la bibliothèque offre d’abord un outillage technique. Le développement récent des outils « discovery » peut être resitué dans cette veine. Deuxièmement, c’est en investissant dans les compétences informationnelles des utilisateurs que la bibliothèque peut lutter contre le versant subjectif de l’infobésité. Dans ce processus, la communication joue un rôle primordial. [less ▲]

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See detailClimate and Security: Evidence, Emerging Risks and a New Agenda
Gemenne, François ULg; Barnett, Jon; Adger, W. Neil et al

in Climatic Change (2014), 123(1), 1-9

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See detailClimate and Security: Evidence, Emerging Risks and a New Agenda
Gemenne, François ULg; Adger, Neil; Barnett, Jon et al

in Climatic Change (2014)

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See detailChine: espoirs et incertitudes à l'ère de Xi Jinping
Florence, Eric ULg

Article for general public (2014)

Pourquoi est-il si difficile de parler de la Chine de manière nuancée, contrastée, sans tomber dans le registre du superlatif et de la généralisation ? À l’occasion d’un important plénum du Parti ... [more ▼]

Pourquoi est-il si difficile de parler de la Chine de manière nuancée, contrastée, sans tomber dans le registre du superlatif et de la généralisation ? À l’occasion d’un important plénum du Parti communiste chinois, le point sur la puissance qui monte [less ▲]

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See detailTransiting planets from WASP-South, Euler and TRAPPIST: WASP-68 b, WASP-73 b and WASP-88 b, three hot Jupiters transiting evolved solar-type stars
Delrez, Laetitia ULg; Van Grootel, Valérie ULg; Anderson, D. R. et al

in Astronomy and Astrophysics (2014)

We report the discovery by the WASP transit survey of three new hot Jupiters, WASP-68 b, WASP-73 b and WASP-88 b. WASP-68 b has a mass of 0.95+-0.03 M_Jup, a radius of 1.24-0.06+0.10 R_Jup, and orbits a V ... [more ▼]

We report the discovery by the WASP transit survey of three new hot Jupiters, WASP-68 b, WASP-73 b and WASP-88 b. WASP-68 b has a mass of 0.95+-0.03 M_Jup, a radius of 1.24-0.06+0.10 R_Jup, and orbits a V=10.7 G0-type star (1.24+-0.03 M_sun, 1.69-0.06+0.11 R_sun, T_eff=5911+-60 K) with a period of 5.084298+-0.000015 days. Its size is typical of hot Jupiters with similar masses. WASP-73 b is significantly more massive (1.88-0.06+0.07 M_Jup) and slightly larger (1.16-0.08+0.12 R_Jup) than Jupiter. It orbits a V=10.5 F9-type star (1.34-0.04+0.05 M_sun, 2.07-0.08+0.19 R_sun, T_eff=6036+-120 K) every 4.08722+-0.00022 days. Despite its high irradiation (2.3 10^9 erg s^-1 cm^-2), WASP-73 b has a high mean density (1.20-0.30+0.26 \rho_Jup) that suggests an enrichment of the planet in heavy elements. WASP-88 b is a 0.56+-0.08 M_Jup planet orbiting a V=11.4 F6-type star (1.45+-0.05 M_sun, 2.08-0.06+0.12 R_sun, T_eff=6431+-130 K) with a period of 4.954000+-0.000019 days. With a radius of 1.70-0.07+0.13 R_Jup, it joins the handful of planets with super-inflated radii. The ranges of ages we determine through stellar evolution modeling are 4.5-7.0 Gyr for WASP-68, 2.8-5.7 Gyr for WASP-73 and 1.8-4.3 Gyr for WASP-88. WASP-73 appears to be a significantly evolved star, close to or already in the subgiant phase. WASP-68 and WASP-88 are less evolved, although in an advanced stage of core H-burning. [less ▲]

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See detailMais ce "p", que veut-il dire finalement ?
Bruyère, Olivier ULg; Dardenne, Nadia ULg

in Medi-Sphere (2014), 437

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See detailThe role of segmentation and investor recognition through the lens of cross-listing activity
Mouchette, Xavier ULg; Muller, Aline ULg; Carrieri, Francesca

Scientific conference (2014, March)

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See detailRupture et repli sur soi. À propos de quelques traits posturaux de Rousseau dans sa correspondance entre 1762 et 1765
Biquet, Stéphanie ULg

in Francalanza, Eric (Ed.) Actes du colloque international "Rousseau en toutes lettres", Brest 22-24 mars 2012 (2014, March)

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See detailUsing stable isotopes to unravel the role of sea-ice in the methane cycle
Sapart, C.J.; Zhou, Jiayun ULg; Niemann, T et al

Poster (2014, March)

Methane (CH4) plays an important role in the Earth’s climate system. The atmospheric CH4 concentration has increased in concert with the industrialization, but since the mid 80’s the CH4 growth rate ... [more ▼]

Methane (CH4) plays an important role in the Earth’s climate system. The atmospheric CH4 concentration has increased in concert with the industrialization, but since the mid 80’s the CH4 growth rate decreased to reach a near-zero level in 2000 and started to increase again from 2007 on. However, the underlying variations in sources and/or sinks that cause these variations are to date not well understood. To predict future climate, it is essential to unravel the processes controlling the CH4 cycle, especially in the Arctic regions, which are highly vulnerable to climate change and contain large CH4 reservoirs. Recently, an unexpected CH4 excess has been reported above Arctic sea-ice showing that sea-ice might play a significant role in the CH4 cycle. Nonetheless, the nature of the process leading to CH4 production in or nearby sea-ice has not yet been identified. We applied a new multi-proxy approach merging atmospheric chemistry, glaciology and biogeochemistry to understand and quantify the processes responsible for the CH4 excess above sea-ice. We performed CH4 isotope (13C and D) analyses on sea-ice samples, as well as microbial (lipid biomarkers) and geochemical measurements, to determine the possible pathways involved in CH4 production and removal in or nearby sea-ice. We will present results from sea-ice samples drilled above the shallow-shelf in Barrow (Alaska) from January to June 2009 as well as above deep Southern Ocean locations in 2013. Those results allow investigating the seasonality and spatial variability in methane formation and removal pathways associated to the methane enclosed in sea-ice. [less ▲]

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See detailFactors driving pCO2 dynamics in sea ice during a large-scale ice tank experiment
Zhou, Jiayun ULg; Delille, Bruno ULg; Tison, J.-L. et al

Conference (2014, March)

According to previous studies, pCO2 fluxes measured over Arctic sea ice are higher than those measured over Antarctic sea ice. We hypothesized that this was due to enhanced respiration in Arctic sea ice ... [more ▼]

According to previous studies, pCO2 fluxes measured over Arctic sea ice are higher than those measured over Antarctic sea ice. We hypothesized that this was due to enhanced respiration in Arctic sea ice, as a consequence of higher riverine inputs of dissolved organic carbon (DOC) into Arctic seawater. We tested this hypothesis during the Interice V experiment at the HSVA (Hamburg) environmental test basin facility. We reproduced the growth and decay cycle of sea ice in replicate mesocosms (1 m3) filled with North Sea water (NSW series), and compared these with another series of mesocosms to which humic-rich river water had been added (10%) to increase the DOC concentration (R series). Primary producers were excluded from the experiment. The evolution of the temperature, salinity, DOC, pCO2 and bacterial biomass and production were measured in ice sampled at regular intervals throughout the experiment, as well as in the under-ice water. In addition, ice-air pCO2 fluxes were continuously monitored over both NSW and R mesocosms. pCO2 values in ice were higher in the R ice than in the NSW ice. This is attributed to the DOC content and bacterial respiration, rather than to the ice physical properties (i.e., ice permeability constrained by the ice temperature and salinity). Indeed, R ice had higher DOC content and bacterial production than the NSW ice while both showed similar physical properties. The evolution of the ice-air pCO2 fluxes was consistent with the evolution of pCO2 in ice. The fluxes were, as expected, positive (from sea ice to the atmosphere) during ice growth and negative (from the atmosphere to the ice) during ice melt. [less ▲]

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See detailSea ice CO2 flux in the Southern Ocean during mid-winter and early spring
Nomura, D.; Delille, Bruno ULg; Dieckmann, G.S. et al

Conference (2014, March)

There seems little doubt that sea ice is permeable to CO2 and other gases although air–sea ice gas flux is more or less inhibited at a brine volume fraction of less than 5% representing the threshold for ... [more ▼]

There seems little doubt that sea ice is permeable to CO2 and other gases although air–sea ice gas flux is more or less inhibited at a brine volume fraction of less than 5% representing the threshold for fluid permeability of sea ice. Generally, air–sea ice CO2 flux is at its minimum in winter due to low sea ice temperatures and consequently reduced permeability despite the fact the partial pressure of CO2 in sea ice is usually high at that time and sea ice has therefore the potential to release CO2 to the atmosphere. Here, we present first evidence that snow laden Antarctic sea ice can act as source for atmospheric CO2 even during mid-winter and early spring. During a mid-winter cruise to the Weddell Sea (AWECS, 2013) and an early spring cruise off east Antarctica (SIPEX-2, 2012), due to thick insulating snow covers, the bottom of the snow and the surface of the sea ice were relatively warm (>–10°C) even though air temperature was sometimes below –30°C. In addition, in both areas, sea ice was characterized by high bulk-salinities, resulting in brine volume fractions that are generally higher than 5%. Automatic “open-closed” chamber measurements indicated positive CO2 fluxes of up to +2.5 mmol C m–2 day–1, illustrating that sea ice acted as a source of atmospheric CO2. Higher fluxes were measured at bare ice surfaces after removing the snow. However, generally low snow densities (mean: 339 kg m–3), indicating a permeable snow cover, facilitated degassing of CO2 at the snow-air interface. Our results therefore suggest that even in the winter and early spring, Antarctic sea ice can act as CO2 source for the atmosphere, particularly in areas with a thick insulating snow cover. [less ▲]

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See detailInvestigating iron and organic matter incorporation in growing sea ice
Janssens, J.; Delille, Bruno ULg; de Jong et al

Conference (2014, March)

High concentration of exopolysacharides (EPS) and iron have been found in sea ice surrounding the Antarctic continent. However, the mechanisms leading to that enrichment remain unclear. Scavenging of iron ... [more ▼]

High concentration of exopolysacharides (EPS) and iron have been found in sea ice surrounding the Antarctic continent. However, the mechanisms leading to that enrichment remain unclear. Scavenging of iron by organic matter in seawater and entrainment during sea ice formation are thought to be responsible for the accumulation of iron in sea ice. EPS could also play a role in the iron passive chelative scavenging process in sea ice and in the increase of iron bioavailability. Our study investigates the processes responsible for the accumulation of iron (dissolved, particulate and total dissolvable iron), EPS, dissolved and particulate organic matter, macro-nutrients (silicic acid, nitrate and nitrite, phosphoric acid and ammonium), chlorophyll a and sea ice algae in young sea ice during an Australian-lead spring voyage off East Antarctica (SIPEX II September – November 2012) and a German-lead winter voyage to the Weddell Sea (AWECS June – August 2013). We used a combination of field- (“in situ”) and laboratory- based sea ice growth time-series experiments. In addition different types of newly formed sea ice as pancake ice, grey ice, frost flowers and slush were collected during both voyages as a means to compare and validate the experimental data. To our knowledge, this is the first report on the biogeochemical properties of newly formed Antarctic pack ice samples in the winter. Ice temperature, salinity and textures are also presented to support the biogeochemical observations at the onset of sea ice formation. [less ▲]

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See detailYear Round survey of Ocean-Sea Ice-Air Exchanges – the YROSIAE survey
Delille, Bruno ULg; Haskell, T.; Champenois, Willy ULg et al

Conference (2014, March)

YROSIAE survey aimed to carry out a year-round survey of land-fast sea ice focusing on the study of sea ice physics and biogeochemistry in order to a) better understand and budget exchanges of energy and ... [more ▼]

YROSIAE survey aimed to carry out a year-round survey of land-fast sea ice focusing on the study of sea ice physics and biogeochemistry in order to a) better understand and budget exchanges of energy and matter across the ocean-sea ice-atmosphere interfaces during sea ice growth and decay and b) quantify their potential impact on fluxes of climate gases (CO2, DMS, CH4, N2O) to the atmosphere and on carbon and macro- nutrients and micro-nutrients export to the ocean. Ice cores, sea water, brines and exported material were collected at regular intervals about 1 km off cape Evans from November 2011 to December 2011 and from September 2012 to December 2012 in trace-metal clean conditions. Samples are processed to characterize both the vertical distribution and temporal changes of climate gases (CO2, DMS, CH4, N2O), CO2-related parameters (dissolved inorganic carbon, total alkalinity and CaCO3 amount), physical parameters (salinity, temperature, texture, 18O), biogeochemical parameters (macro-nutrients, particulate and dissolved organic carbon, δ13C, δ30Si and δ15N, micro-nutrients - including iron) and biological parameters ( chlorophyll a, primary production within sea ice derived from O2:Ar and O2:N ratios, autotrophic species determination, bacterial cell counts a.s.o.). In addition, we deployed a micro-meterological tower and automatic chambers to measure air-ice CO2 fluxes. Continuous measurements of ice temperature and ice accretion or melting, both at the ice-ocean and the ice-atmosphere interfaces were provided by an “Ice-T” ice mass balance buoy. Sediment traps collected particles below the ice between 10 and 70 m, while dust collectors provided a record of a full suite of trace metal and dust at different levels above the ground. We will present the aims, overall approach and sampling strategy of the YROSIAE survey. In addition we will also discuss CO2 dynamics within the ice and present temporal air-ice CO2 fluxes over the year. We will provide a first budget of air-ice CO2 fluxes during ice growth for Antarctica sea ice and discuss the impact of the snow cover on air-ice CO2 fluxes. [less ▲]

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See detailDimethyl sulfide and dimethylsulfoniopropionate profiles in sea ice during winter in the Weddell Sea
Uhlig, C.; Tison, J.-L.; Rintala, J. et al

Conference (2014, March)

This study presents profiles of the organic sulphur components dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP) in sea ice cores collected during the AWECS (Antarctic Winter Ecosytem Climate ... [more ▼]

This study presents profiles of the organic sulphur components dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP) in sea ice cores collected during the AWECS (Antarctic Winter Ecosytem Climate Study) cruise on RV Polarstern (ANT29-6) in the Weddell Sea. DMS is a semi-volatile sulfur component and under discussion to be climate active, as its oxidation products might act as cloud condensation nuclei - thus cooling the atmosphere. It is produced by enzymatic cleavage of the precursor DMSP, which is synthesized by various types of phytoplankton and serves for example as compatible solute and cryoprotectant. Due to the physico-chemical conditions given, i.e. the high salinity and the icy matrix, sea ice as habitat favors production of high levels of DMSP by the inhabiting microalgae. DMSP and DMS are frequently found in high concentrations in sea ice during spring and summer. The aim of this study was to investigate DMS(P) levels in winter sea ice as data for the winter season is yet scarce, but is of importance for global budgeting. Preliminary results of our study show that DMS(P) production in sea ice in the Weddell Sea is also significant during winter. This stands in contrast to previous measurements in Arctic winter sea ice (CFL-IPY cruise in the Circumpolar Flaw Lead Polynya), where DMS(P) concentrations were very low. Possible explanations for the differences between DMS(P) levels in the Arctic and Antarctic might be the different snow cover and thus insulation, light regimes and also microbial community structure within the ice. DMS(P) levels were generally correlated with chlorophyll a concentrations, although the details are complex and seem to be influenced by species composition and species specific DMSP/Chla ratios. The DMS profiles mirrored the permeability of the sea ice following DMSP in the impermeable areas while showing losses to the ice surface and ice-water interface in the more permeable regions. Winter DMS(P) profiles are furthermore compared to data collected during the following spring cruise of RV Polarstern (ANT29-7) in the Weddell Sea. [less ▲]

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