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See detailConditioning materials with biomacromolecules: composition of the adlayer and influence on cleanability
Toure, Yetioman ULg; Genet, J. Michel; Dupont-Gillain, C. Christine et al

in Journal of Colloid and Interface Science (in press)

The influence of substrate hydrophobicity and biomacromolecules (dextran, bovine serum albumin - BSA) adsorption on the cleanability of surfaces soiled by spraying aqueous suspensions of quartz particles ... [more ▼]

The influence of substrate hydrophobicity and biomacromolecules (dextran, bovine serum albumin - BSA) adsorption on the cleanability of surfaces soiled by spraying aqueous suspensions of quartz particles (10 to 30 µm size), then dried, was investigated using glass and polystyrene as substrates. The cleanability was evaluated using radial flow cell (RFC). The surface composition was determined by X-ray photoelectron spectroscopy (XPS). The interpretation of XPS data allowed the complexity due to the ubiquitous presence of organic contaminants to be coped with, and the surface composition to be expressed in terms of both the amount of adlayer and the mass concentration of adlayer constituents. When soiled with a suspension of particles in water, glass was much less cleanable than polystyrene, which was attributed to its much lower water contact angle, in agreement with previous observations on starch soil. Dextran was easily desorbed and did not affect the cleanability. The presence of BSA at the interface strongly improved the cleanability of glass while the contact angle did not change appreciably. In contrast, soiling polystyrene with quartz particles suspended in a BSA solution instead of water did not change markedly the cleanability, while the contact angle was much lower and the aggregates of soiling particles were more flat. These observations are explained by the major role of capillary forces developed upon drying, which influence the closeness of the contact between the soiling particles and the substrate and, thereby, the adherence of particles. The capillary forces are proportional to the liquid surface tension and depend in a more complex way on contact angles of the particles and of the substrate. The dependence of cleanability on capillary forces, and in particular on the liquid surface tension, is predominant as compared with its dependence on the size and shape of the soiling aggregates, which influence the efficiency of shear forces exerted by the flowing water upon cleaning. [less ▲]

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See detailDose-dependent effect of experimental Schmallenberg virus infection in sheep
Poskin, A; Martinelle, Ludovic ULg; Mostin, L et al

in Veterinary Journal (in press)

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See detailOrganic Rankine Cycles including fluid selection
Lemort, Vincent ULg; Declaye, Sébastien ULg; Quoilin, Sylvain ULg

in Handbook of Clean Energy Systems (in press)

An Organic Rankine Cycle (ORC) is similar to a steam Rankine cycle, except that the working fluid is not water but an organic compound, such as a refrigerant or a hydrocarbon, characterized by a lower ... [more ▼]

An Organic Rankine Cycle (ORC) is similar to a steam Rankine cycle, except that the working fluid is not water but an organic compound, such as a refrigerant or a hydrocarbon, characterized by a lower ebullition temperature than that of water. Hence lower temperature heat sources can be exploited such as solar energy, geothermal energy and waste heat recovery from many different processes. During the design phase of an ORC system, the selection of the working fluid must be conducted in parallel with the selection and the sizing of the components (mainly the expansion machine, the pump and the heat exchangers) and with the definition of the cycle architecture. This approach allows taking into consideration all technical constraints. Relevant properties of working fluids that should be considered during their selection are listed. Major characteristics of available displacement and turbo-expander technologies are described. The impact of the pump performance on the overall performance is discussed and strategies to increase the available NPSH are proposed. Finally, improved cycle architectures are introduced. Major applications of ORC systems are described: geothermal power plants, biomass CHP plants, waste heat recovery in industry, waste heat recovery on internal combustion engines and solar power plants. All these applications differ by the nature of the heat source and heat sink, the integration of the ORC with these sources and sinks, and the range of installed capacities. These differences yield specific designs, which are described. Performance achieved by systems in operation or prototypes are presented. [less ▲]

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See detailPSI Mehler reaction is the main alternative photosynthetic electron pathway in Symbiodinium sp., symbiotic dinoflagellates of cnidarians
Roberty, Stéphane ULg; Bailleul, Benjamin ULg; Berne, Nicolas et al

in New Phytologist (in press)

• Photosynthetic organisms have evolved various photoprotective and regulatory mechanisms to cope with changing and high light intensities. The nature and relative amplitude of these mechanisms is matter ... [more ▼]

• Photosynthetic organisms have evolved various photoprotective and regulatory mechanisms to cope with changing and high light intensities. The nature and relative amplitude of these mechanisms is matter of debate in dinoflagellates that live in symbiosis with cnidarians. In this work, the amplitude of photosynthetic alternative electron flows to oxygen (chlororespiration, Mehler reaction, mitochondrial respiration) and PSI cyclic electron flow were investigated in Symbiodinium clades A1, B1 and F1. • Cultured Symbiodinium strains were maintained semi-continuously under identical environmental conditions. Joint measurements of oxygen evolution, fluorescence emission, and absorption changes at specific wavelengths were used to evaluate PSI and PSII electron transfer rates (ETR). • A light-dependent and O2-dependent ETR was observed in all strains. This ETR involved PSII and PSI and was insensitive to addition of mitochondrial and carbon fixation inhibitors. • These results demonstrate that photoreduction of oxygen downstream of PSI by the so-called Mehler reaction is the main alternative electron sink at the onset and steady state of photosynthesis in all strains. This mechanism in Symbiodinium sustains significant levels of photosynthetic electron flux under high light, thus acting as a photoprotective mechanism and increasing the ATP/NADPH ratio by the electron transfer chain. [less ▲]

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See detailL’auteur de la Passio sanctae Salsae a-t-il aussi écrit la Passio sancti Fabii ?
Fialon, Sabine ULg

in Meyers, Jean; Fialon, Sabine (Eds.) La Passio sanctae Salsae. Recherches sur une passion tardive d’Afrique du Nord. Avec une nouvelle édition critique d’A. M. Piredda et une traduction annotée du G.R.A.A. (in press)

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See detailDominant amphipods of Posidonia oceanica seagrass meadows display considerable trophic diversity
Michel, Loïc ULg; Dauby, Patrick ULg; Gobert, Sylvie ULg et al

in Marine Ecology (in press)

Gut content examination and trophic markers (fatty acids, stables isotopes of C and N) were combined to delineate the diet of the dominant species of amphipods from Mediterranean Posidonia oceanica ... [more ▼]

Gut content examination and trophic markers (fatty acids, stables isotopes of C and N) were combined to delineate the diet of the dominant species of amphipods from Mediterranean Posidonia oceanica seagrass meadows and to highlight trophic diversity among this community. Our results indicate that, although all dominant species heavily relied on macroalgal epiphytes, considerable interspecific dietary differences existed. Carbon stable isotope ratios notably showed that some of the amphipod species favored grazing on epiphytes from leaves or litter fragments (Apherusa chiereghinii, Aora spinicornis, Gammarus aequicauda), while others like Dexamine spiniventris preferred epiphytes from rhizomes. The remaining amphipods (Caprella acanthifera, Ampithoe helleri and Gammarella fucicola) readily consumed both groups. In addition, SIAR modeling suggested that most species had a mixed diet, and relied on several food items. Fatty acid analysis and gut contents revealed that contribution of microepiphytic diatoms and of benthic and suspended particulate organic matter to the diet of amphipods were anecdotal. None of the examined species seemed to graze on their seagrass host (low 18:2(n-6) and 18:3(n-3) fatty acids contents), but G. aequicauda partly relied on seagrass leaf detritus, as demonstrated by the lesser 13C-depletion of their tissues. Overall, our findings suggest that amphipods, because of their importance in transfers of organic matter from primary producers and detritus to higher rank consumers, are key-items in P. oceanica associated food webs. [less ▲]

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See detailJews and Christians in Late Africa : an hagiographical perspective
Fialon, Sabine ULg

in Lanfranchi, Pierluigi; Verheyden, Joseph (Eds.) Jews and Christians in Late Antiquity (titre provisoire) (in press)

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See detail« Semen est sanguis christianorum » (Apol. 50, 13). Tertullien et l'hagiographie africaine
Fialon, Sabine ULg

in Lagouanère, Jérôme; Fialon, Sabine (Eds.) Tertullianus Afer. Tertullien et la littérature chrétienne d'Afrique, IIe-VIe siècle (in press)

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See detailPET imaging analysis using a parcelation approach and multiple kernel classification
Segovia-Román, Fermín ULg; Phillips, Christophe ULg

in International Workshop on Pattern Recognition in Neuroimaging, Tübingen 4-6 June 2014 (in press)

Positron Emission Tomography (PET) is a non-invasive medical imaging modality that provides information about physiological processes. Due to its ability to measure the brain metabolism, it is widely used ... [more ▼]

Positron Emission Tomography (PET) is a non-invasive medical imaging modality that provides information about physiological processes. Due to its ability to measure the brain metabolism, it is widely used to assist the diagnosis of neurodegenerative disorders such as Alzheimer’s disease (AD) of Parkinsonism. In order to avoid the subjectivity inherent to the visual exploration of the images, several computer systems to analyze PET data were developed during the last years. However, dealing with the huge amount of information provided by PET imaging is still a challenge. In this work we present a novel methodology to analyze PET data that improves the automatic differentiation between controls and AD patients. First the images are divided into small regions or parcels, defined either anatomically, geometrically or randomly. Secondly, the accuray of each single region is estimated using a Support Vector Machine (SVM) classifier and a cross-validation approach. Finally, all the regions are assessed together using multiple kernel SVM with a kernel per region. The classifier is built so that the most discriminative regions have more weight in the final decision. This method was evaluated using a PET dataset that contained images from healthy controls and AD patients. The classification results obtained with the proposed approach outperformed two recently reported computer systems based on Principal Component Analysis and Independent Component Analysis. [less ▲]

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See detailSophistique et Philosophie: Platon, héritier de Protagoras
Gavray, Marc-Antoine ULg

Book published by Vrin (in press)

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See detailGenetic parameters for mid-infrared methane indicators based on milk fatty acids in dairy cows
Kandel, Purna Bhadra ULg; Gengler, Nicolas ULg; Soyeurt, Hélène ULg

in Journal of Applied Animal Research (in press)

Dairy production is identified as a major source of methane (CH4) emissions. Selective breeding canbe one method used to mitigate CH4 emissions but practical and cheap measurement of this trait is not ... [more ▼]

Dairy production is identified as a major source of methane (CH4) emissions. Selective breeding canbe one method used to mitigate CH4 emissions but practical and cheap measurement of this trait is not currently available. The mid-infrared (MIR) prediction of milk fatty acids is relevant in this context. Five MIR methane indicators were derived from the literature and were calibrated from 600 samples analyzed by gas chromatography. Genetic parameters for these traits were estimated using single trait random regression test-day models from 619,265 records collected from 2007 to 2011 on 71,188 Holstein cows in their first three lactations. For the published indicator showing the highest relationship with the methane data (R2 = 0.88), the average daily heritability was 0.34±0.01, 0.37±0.01 and 0.34±0.01 for the first three lactations, respectively. The methane emission (g/day) was increased from beginning of lactation, reached at the highest in peak of lactation and decreased towards end of lactation. The largest differences between estimated breeding values (EBV) of sires having daughters in production eructing the highest and the lowest methane content was 21.80, 22.75 and 24.89 kg per lactation for the first three parities. Positive genetic correlations were estimated between indicator traits and milk fat and protein content. Low negative correlation was observed with milk yield. In conclusion, this study shows the feasibility to predict methane indicator traits by MIR. Moreover, the estimated genetic parameters suggest also a potential genetic variability of the quantity of methane eructed by dairy cows. [less ▲]

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See detailAntiquité tardive et christianisme africains dans l'Africa romana : un bilan historiographique
Fialon, Sabine ULg

in Ruggeri, Paola (Ed.) L’Africa romana XX. Momenti di continuita e rottura : bilancio di 30 anni di convegni de l’Africa romana (in press)

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See detailPlaton: le Politique, introduction, traduction et commentaire
Dixsaut, Monique; El Murr, Dimitri; Gavray, Marc-Antoine ULg et al

Book published by Vrin (in press)

Nouvelle traduction commentée et annotée du Politique de Platon

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See detailMulti-period vehicle loading with stochastic release dates
Arda, Yasemin ULg; Crama, Yves ULg; Kronus, David ULg et al

in EURO Journal on Transportation and Logistics (in press)

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be ... [more ▼]

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be formulated as a large-scale set covering problem. Several heuristic algorithms are proposed to generate decision policies for the stochastic optimization model over a long rolling horizon. The resulting policies have been extensively tested on instances which display the main characteristics of the industrial case-study that motivated the research. The tests demonstrate the benefits of the multi-period stochastic model over simple myopic strategies. A simple and efficient heuristic is shown to deliver good policies and to be robust against errors in the estimation of the probability distribution of the release dates. [less ▲]

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See detailLe monde du représentable: de Lotze à la phénoménologie
Dewalque, Arnaud ULg

in Boccaccini, Federico (Ed.) Lotze et son héritage. Son influence et son impact sur la philosophie du XXe siècle (in press)

Dans ce chapitre, je me propose de réévaluer, au moins partiellement, le sens et la portée de la théorie de la « validité » (Gelten, Geltung) développée par Lotze dans sa grande Logique de 1874. Je ... [more ▼]

Dans ce chapitre, je me propose de réévaluer, au moins partiellement, le sens et la portée de la théorie de la « validité » (Gelten, Geltung) développée par Lotze dans sa grande Logique de 1874. Je suggérerai que le rapprochement traditionnellement invoqué entre Lotze et Bolzano est trompeur, puisqu’il a sans doute assez largement contribué à masquer la dimension eidétique et « matérielle » de la théorie lotzéenne de la validité (§1). L’une des idées centrales qui se cache derrière la notion de « validité », en effet, est que les contenus de représentation – et, exemplairement, les contenus de représentations sensorielles (les concepts de couleurs, de sons, etc.) – forment une sphère intrinsèquement structurée par des relations d’un certain genre. Contrairement aux relations logiques traditionnelles (comme la contradiction) et aux relations logico-syntaxiques, qui structurent aussi le « monde du représensable » d’un autre point de vue (§2), les relations dont il est question ici sont non formalisables, car elles sont fondées dans l’essence même des phénomènes, pris « en soi », c’est-à-dire indépendamment de leur instanciation dans un objet du monde spatio-temporel et de leur appréhension par un sujet psycho-physique (§3). [less ▲]

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See detailGenetic analysis of pig survival up to commercial weight in a crossbred population
Dufrasne, Marie ULg; Misztal, Ignacy; Tsuruta, Shogo et al

in Livestock Science (in press)

Records from 99,384 crossbred pigs from Duroc sires and Large White x Landrace dams were used to estimate genetic parameters for survival traits at different stages of the fattening period, and their ... [more ▼]

Records from 99,384 crossbred pigs from Duroc sires and Large White x Landrace dams were used to estimate genetic parameters for survival traits at different stages of the fattening period, and their relations with final weight. Traits analyzed were preweaning mortality (PWM), culling between weaning and harvesting (Call), culling during the farrowing period (Cfar), in the nursery site (Cnur), during the finishing phase (Cfin), and hot carcass weight (HCW). Because of the binary nature of PWM and culling traits, threshold-linear models were used: Model 1, including PWM, Call, and HCW; Model 2, including PWM, Cfar, Cnur, Cfin, and HCW. Both models included sex and parity number as fixed effects for all traits. Contemporary groups were considered as fixed effect for HCW and as random effects for the binary traits. Random effects were sire additive genetic, common litter, and residual effects for all traits and models. Heritability estimates were 0.03 for PWM, and 0.15 for HCW with both models, 0.06 for Call with Model 1, and 0.06 for Cfar, 0.14 for Cnur, and 0.10 for Cfin with Model 2. Litter variance explained a large part of the total variance and its influence declined slightly with age. For Model 1, genetic correlations were -0.36 between PWM and Call, -0.02 between PWM and HCW, and -0.25 between Call and HCW; correlations for litter effect were -0.15 between PWM and Call, -0.19 between PWM and HCW, and -0.21 between Call and HCW. For Model 2, genetic correlations were all positive between PWM and culling traits, except between PWM and Cnur (-0.61). Genetic correlations between HCW and the other traits were moderate and negative to null. Correlations for common litter effect were all negative between traits, except between Cfar and Cfin, and between Cnur and Cfin. Heritability of PWM and culling traits increased with age period. Therefore, selection for survival after weaning may be more efficient. The low genetic correlations between PWM and culling traits suggest that different genes influence pre- and postweaning mortality. The HCW was not correlated with the other traits. However, relationships are not strongly unfavorable, therefore selection for survival and high final weight is possible. [less ▲]

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