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See detailFrançois Ier et les arts du Nord (1515-1547). Des liens à explorer et à appronfondir encore
Fagnart, Laure ULg; Lecocq, Isabelle

in Fagnart, Laure; Lecocq, Isabelle (Eds.) François Ier et les arts du Nord (1515-1547) (2017)

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See detailJean Clouet vs Joos van Cleve
Fagnart, Laure ULg

in Fagnart, Laure; Lecocq, Isabelle (Eds.) François Ier et les arts du Nord (1515-1547) (2017)

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See detailThe Epoch of Smart Cities and Innovation.
Crutzen, Nathalie ULg; Marolla, Cesar

in Marolla, Cesar (Ed.) Climate Health Risks in Megacities: Sustainable Management and Strategic Planning (2017)

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See detailPost-scriptum à La Misère du monde 25 ans après : Bourdieu, le peuple et son suicide
Cormann, Grégory ULg

in Provenzano, François; Goin, Emilie (Eds.) Usages du peuple (2017)

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See detailIron-dependent nitrogen cycling in a ferruginous lake and the nutrient status of Proterozoic oceans
Michiels, Celine C.; Darchambeau, François ULg; Roland, Fleur ULg et al

in Nature Geoscience (2017), advance online publication

Nitrogen limitation during the Proterozoic has been inferred from the great expanse of ocean anoxia under low-O2 atmospheres, which could have promoted NO3- reduction to N2 and fixed N loss from the ocean ... [more ▼]

Nitrogen limitation during the Proterozoic has been inferred from the great expanse of ocean anoxia under low-O2 atmospheres, which could have promoted NO3- reduction to N2 and fixed N loss from the ocean. The deep oceans were Fe rich (ferruginous) during much of this time, yet the dynamics of N cycling under such conditions remain entirely conceptual, as analogue environments are rare today. Here we use incubation experiments to show that a modern ferruginous basin, Kabuno Bay in East Africa, supports high rates of NO3- reduction. Although 60 of this NO3- is reduced to N2 through canonical denitrification, a large fraction (40\%) is reduced to NH4+, leading to N retention rather than loss. We also find that NO3- reduction is Fe dependent, demonstrating that such reactions occur in natural ferruginous water columns. Numerical modelling of ferruginous upwelling systems, informed by our results from Kabuno Bay, demonstrates that NO3- reduction to NH4+ could have enhanced biological production, fuelling sulfate reduction and the development of mid-water euxinia overlying ferruginous deep oceans. This NO3- reduction to NH4+ could also have partly offset a negative feedback on biological production that accompanies oxygenation of the surface ocean. Our results indicate that N loss in ferruginous upwelling systems may not have kept pace with global N fixation at marine phosphorous concentrations (0.04-0.13[thinsp][mu]M) indicated by the rock record. We therefore suggest that global marine biological production under ferruginous ocean conditions in the Proterozoic eon may thus have been P not N limited. [less ▲]

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See detailOptimized approach to retrieve information on atmospheric carbonyl sulfide (OCS) above the Jungfraujoch station and change in its abundance since 1995
Lejeune, Bernard ULg; Mahieu, Emmanuel ULg; Vollmer, M. K. et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (2017), 186

In this paper, we present an optimized retrieval strategy for carbonyl sulfide (OCS), using Fourier transform infrared (FTIR) solar observations made at the high-altitude Jungfraujoch station in the Swiss ... [more ▼]

In this paper, we present an optimized retrieval strategy for carbonyl sulfide (OCS), using Fourier transform infrared (FTIR) solar observations made at the high-altitude Jungfraujoch station in the Swiss Alps. More than 200 lines of the nu3 fundamental band of OCS have been systematically evaluated and we selected 4 microwindows on the basis of objective criteria minimizing the effect of interferences, mainly by solar features, carbon dioxide and water vapor absorption lines, while maximizing the information content. Implementation of this new retrieval strategy provided an extended time series of the OCS abundance spanning the 1995-2015 time period, for the study of the long-term trend and seasonal variation of OCS in the free troposphere and stratosphere. Three distinct periods characterize the evolution of the tropospheric partial columns: a first decreasing period (1995-2002), an intermediate increasing period (2002-2008), and the more recent period (2008-2015) which shows no significant trend. Our FTIR tropospheric and stratospheric time series are compared with new in situ gas chromatography mass spectrometry (GCMS) measurements performed by Empa (Laboratory for Air Pollution/Environmental Technology) at the Jungfraujoch since 2008, and with space-borne solar occultation observations by the ACE-FTS instrument on-board the SCISAT satellite, respectively, and they show good agreement. The OCS signal recorded above Jungfraujoch appears to be closely related to anthropogenic sulfur emissions. [less ▲]

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See detailEntrepreneurial teams in social entrepreneurship: When team heterogeneity facilitates organizational hybridity
Dufays, Frédéric ULg; Huybrechts, Benjamin ULg

in Ben-Hafaïedh, Cyrine; Cooney, Thomas (Eds.) Research handbook on entrepreneurial teams: Theory and practice (2017)

This chapter examines the composition of teams involved in social entrepreneurship and more particularly their heterogeneity in terms of “institutional logics”. It proposes that when social welfare and ... [more ▼]

This chapter examines the composition of teams involved in social entrepreneurship and more particularly their heterogeneity in terms of “institutional logics”. It proposes that when social welfare and market logics are integrated within founding teams, such hybridity is likely to infuse the whole entrepreneurial process to ultimately lead to the creation of a social enterprise as a “hybrid” organization. To theorize this process, a model is proposed that examines the implications of entrepreneurial team heterogeneity in social entrepreneurship. It makes clear that complexity and dynamism, in particular with regard to individuals’ social network structure, as well as interactions between team members, are necessary to understand the impact of team composition on the entrepreneurial process. An illustrative case study is presented to demonstrate the practical relevance of the model. [less ▲]

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See detailIntroduction
Masson, Christophe ULg

E-print/Working paper (2017)

Introduction de l'Assemblée générale de Ménestrel – 35e journée d'étude du Réseau des Médiévistes belges de Langue française. Le Moyen Âge dans les (nouveaux) médias. Quelle place pour les médiévistes  ... [more ▼]

Introduction de l'Assemblée générale de Ménestrel – 35e journée d'étude du Réseau des Médiévistes belges de Langue française. Le Moyen Âge dans les (nouveaux) médias. Quelle place pour les médiévistes ? Université de Liège, 7-8 octobre 2016 [less ▲]

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See detailApproche phénoménologique du soi psychopathique
Englebert, Jérôme ULg

in Cormann, Grégory; Boccaccini, Federico (Eds.) Le soi agent : Approches phénoménologiques (2017)

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See detailSustainability and management control. Exploring and theorizing control patterns in large European firms
Crutzen, Nathalie ULg; Zvezdov, Dimitar; Schaltegger, Stefan

in Journal of Cleaner Production (2017), 143

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See detailOn the Elaboration of Metal-Ceramic Composite Coatings by Laser Cladding
Mertens, Anne ULg; L'Hoest, Thibaut; Magnien, Julien et al

in Materials Science Forum (2017), 879

This paper reports on a preliminary investigation into the elaboration, by the additive process known as laser cladding, of composite coatings with a matrix of stainless steel 316L reinforced with varying ... [more ▼]

This paper reports on a preliminary investigation into the elaboration, by the additive process known as laser cladding, of composite coatings with a matrix of stainless steel 316L reinforced with varying contents of tungsten (WC) or silicon carbides (SiC) particles. Laser cladding is characterised by ultra-fast solidification and cooling rates, thus giving rise to ultra-fine out-of-equilibrium microstructures and potentially enhanced mechanical properties. Both types of composite coatings – i.e. with SiC or WC ‒ are compared in terms of their microstructures and hardness. Special attention is given to the dissolution of the carbides particles and to interfacial reactions taking place between the particles and the metallic matrix. [less ▲]

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See detailDEVELOPMENT OF ANALYTICAL TOOLS FOR THE DETERMINATION OF MARKERS OF LIPID ALTERATION IN FOOD
Douny, Caroline ULg

Doctoral thesis (2017)

It is now well-known that n-3 polyunsaturated fatty acids (omega-3 PUFA) have beneficial effects on health but are also rapidly oxidized in potentially toxic compounds, which means that healthy food ... [more ▼]

It is now well-known that n-3 polyunsaturated fatty acids (omega-3 PUFA) have beneficial effects on health but are also rapidly oxidized in potentially toxic compounds, which means that healthy food products, rich in n-3 PUFA, can become toxic for the consumer if not stored or processed appropriately. The main objective of this work was to develop new analytical tools to study markers of lipids alteration in food, in order to allow an adequate monitoring of possible toxic compounds in n-3 PUFA rich food products. The first chapter of this PhD thesis is a literature review about fatty acids, their oxidation and the different oxidation products generated. The different analytical techniques used to study the oxidative stability of polyunsaturated fatty acids and their degradation products in food are also described. Chapter 2 describes the development of a gas chromatography coupled to mass spectrometry (GC-MS) method to analyze the fatty acids in food. The method was applied to eggs and pork (both standard and n-3 enriched) submitted to various cooking processes and storage conditions. This study confirmed that the fat of standard eggs or pork from the Belgian market cannot be considered as a source ofn-3 PUFA.. Indeed, in this work, we measured no n-3 PUFA in meat or only around 2 % for eggs, while the fat of both enriched eggs and pork contained about 10 % of n-3 fatty acids. After storage or cooking without culinary fat no change of the fatty acid profile was observed, in standard eggs or pork. We made the same observation for n-3 enriched products, except for some cooking processes (pan-frying and oven cooking), which induced a slight but significant loss of n-3 fatty acids in n-3 enriched eggs or pork. The fairly stable behavior of the fatty acids after various cooking and storage experiments indicates that the fatty acid profile is not a good marker of lipid alteration. As a consequence, this work was oriented to the development of analytical tools to evaluate the presence of toxic aldehydes in food and feed as secondary oxidation products coming from polyunsaturated fatty acids. Chapter 3 is dedicated to the study of the oxidative stability of linseed oil, an oil rich in n-3 fatty acids. Section 3.1 describes the development of a liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) method to evaluate the aldehyde content in linseed oil. After optimisation of the extraction, derivation, detection and quantification steps, the method was validated according to guidelines from the European legislation as well as the recommendations of the AFNOR protocol NF V 03-110 (AFNOR, 2010). The evaluated parameters included specificity/selectivity, recovery, precision, accuracy, uncertainty, limits of detection and quantification, determined using the concept of accuracy profiles. When the method was applied to first pressure linseed oil stored for several days at 60 °C according to the Schaal oven test, it was shown that 4-hydroxy-2E-hexenal (4-HHE) was the most produced aldehyde. In Section 3.2, the different patterns of oxidation of linseed oil in real-time and accelerated aging assays were investigated, in order to verify the hypothesis commonly accepted for vegetal oil that one day aging at 60 °C is equivalent to one month real time aging at room temperature. Oxidation was evaluated with the peroxide value and para-anisidine value, as well as the content in conjugated dienes and aldehydes. All four indicators of oxidation showed very different kinetic behaviours at 20 and 60 °C, showing that the hypothesis (1 day at 60 °C = 1 month at 20 °C) is not valid for linseed oil. Chapter 4 describes the adaptation and the validation of a LC-MS/MS method to determine aldehydes in animal feed samples. Indeed, as animal feed is often enriched with linseed to increase the human intake of n-3 fatty acids through the consumption of food from animal origin, the study of the oxidative stability of n-3 enriched animal feed is also of interest. To achieve that goal, the LC-MS/MS method previously developed for linseed oil was adapted to include more aldehydes and was validated using the same guidelines as in section 3.1. Finally, chapter 5 presents the discussion and conclusions about the developed methods and the results obtained as well as their comparison with literature. Future prospects to improve the evaluation of and the exposure to the markers of lipid alteration in food are proposed. [less ▲]

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See detailEvaluation of hazardous chemicals in edible insects and insect-based food intended for human consumption
Poma, G; Cuykx, M; Amato, E et al

in Food and Chemical Toxicology (2017), 100

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See detailComment former à une vision élargie de l’évaluation formative en vue de réguler efficacement les apprentissages mathématiques des élèves ?
Fagnant, Annick ULg; Demonty, Isabelle ULg

in Detroz, Pascal; Crahay, Marcel; Fagnant, Annick (Eds.) L’évaluation à la lumière des contextes et des disciplines (2017)

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See detailNumerical Methods
Agelet de Saracibar, Carlos; Boman, Romain ULg; Bussetta, Philippe et al

in Schmitz, Georg; Prahl, Ulrich (Eds.) Handbook of Software Solutions for ICME, (2017)

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See detailAntiplasmodial activity of Heinsia crinita (Rubiaceae) and identification of new iridoids.
Tshisekedi Tshibangu, P.; Mutwale Kapepula, P.; Kabongo Kapinga, M. J. et al

in Journal of Ethnopharmacology (2017), 196

ETHNOPHARMACOLOGICAL RELEVANCE: Heinsia crinita is used in traditional medicine for the treatment of febrile illness and erectile dysfunction. Its stem bark powder is found in some peripheral markets in ... [more ▼]

ETHNOPHARMACOLOGICAL RELEVANCE: Heinsia crinita is used in traditional medicine for the treatment of febrile illness and erectile dysfunction. Its stem bark powder is found in some peripheral markets in the Democratic Republic of the Congo (DRC) as a remedy against malaria. Investigations were conducted on crude extracts of leaves, fruits and stem barks in view to validate their use and to determine which plant part possesses the best antiplasmodial properties. MATERIALS AND METHODS: Different plant parts were extracted with methanol, ethanol and dichloromethane. Based on the preliminary assays, the dichloromethane extract of the stem bark was subjected to fractionation using preparative HPLC system and column chromatography. This step led to the isolation of two new iridoids which had their structures elucidated by NMR, UV, MS and FT-IR spectroscopic techniques. Extracts and pure compounds were tested in vitro against the 3D7 strain of Plasmodium falciparum. The inhibition of the parasite growth was evaluated in vitro by colorimetric method (p-LDH assay) and their cytotoxicity evaluated in vitro against the human non-cancer fibroblast cell line (WI38) through WST1 assay. The in vivo antiplasmodial activity was assessed by the inhibition of Plasmodium berghei growth in infected mice treated with the ethanol extract of H. crinita stem bark at the concentrations of 200 and 300mg/Kg/day per os, using a protocol based on the 4-d suppressive test of Peters and compared to a non-treated negative control group of mice (growth =100%). Finally the antioxidant activity of the same extract was evaluated using ABTS, DPPH and cell-based assays. RESULTS: A moderate in vitro antiplasmodial activity was observed for the dichloromethane extract of the stem bark of H. crinita (IC50 =29.2+/-1.39microg/mL) and for the two new iridoids, lamalbide 6, 7, 8- triacetate (IC50 =16.39+/-0.43microg/mL) as well as for its aglycone lamiridosin 6, 7, 8-triacetate (IC50 =0.44.56+/-1.12microg/mL). The ethanolic stem bark extract (200 and 300mg/kg/day, oral route) showed a moderate in vivo antimalarial activity in Plasmodium berghei-infected mice with 27.84+/-2.75% and 48.54+/-3.76% of inhibition of the parasite growth, respectively (p<0.01).). This extract displayed high cellular antioxidant activity using dichlorofluorescein-diacetate (DCFDA) on HL-60 monocytes. These crude extracts and pure compounds tested at the higher concentration of 100microg/mL did not show any cytotoxicity against WI38 cells. CONCLUSIONS: The results showed that H. crinita extracts possess antimalarial activity and contain some unusual iridoids with moderate antiplasmodial activity, therefore justifying to some extent its traditional use by the local population in DRC for this purpose. This is the first report of the isolation and antiplasmodial activity of these two new iridoids. [less ▲]

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See detailInvestigation of the added mass method for seismic design of lock gates
Buldgen, Loïc ULg; Le Sourne, Hervé; Caprace, Jean-David ULg et al

in Engineering Structures (2017)

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See detailDancing without listening to the music: learning from some failures of the ‘national innovation systems’ in Latin America
Delvenne, Pierre ULg; Thoreau, François ULg

in Kuhlmann, Stefan; Ordóñez-Matamoros, Gonzalo (Eds.) Research Handbook on Innovation Governance for Emerging Economies (2017)

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See detailFast In-Plane Dynamics of a Beam with Unilateral Constraints
Liakou, Anna; Denoël, Vincent ULg; Detournay, Emmanuel

in Journal of Engineering Mechanics (2017), 0(0), 04016116

Detailed reference viewed: 20 (3 ULg)