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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 detailMultiscale modelling framework for the fracture of thin brittle polycrystalline films - Application to polysilicon
Mulay, Shantanu; Becker, Gauthier ULg; Vayrette, Renaud et al

in Computational Mechanics (in press)

Micro-electro-mechanical systems (MEMS) made of polycrystalline silicon are widely used in several engineering fields. The fracture properties of polycrystalline silicon directly affect their reliability ... [more ▼]

Micro-electro-mechanical systems (MEMS) made of polycrystalline silicon are widely used in several engineering fields. The fracture properties of polycrystalline silicon directly affect their reliability. The effect of the orientation of grains on the fracture behaviour of polycrystalline silicon is investigated out of the several factors. This is achieved, firstly, by identifying the statistical variation of the fracture strength and critical strain energy release rate, at the nanoscopic scale, over a thin freestanding polycrystalline silicon film, having mesoscopic scale dimensions. The fracture stress and strain at the mesoscopic level are found to be closely matching with uniaxial tension experimental results. Secondly, the polycrystalline silicon film is considered at the continuum MEMS scale, and its fracture behaviour is studied by incorporating the nanoscopic scale effect of grain orientation. The entire modelling and simulation of the thin film is achieved by combining the discontinuous Galerkin method and extrinsic cohesive law describing the fracture process. [less ▲]

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See detailA note on the equivalence between observed and expected information functions with polytomous IRT models
Magis, David ULg

in Journal of Educational & Behavioral Statistics (in press)

The purpose of this note is to study the equivalence of observed and expected (Fisher) information functions with polytomous item response theory (IRT) models. It is established that observed and expected ... [more ▼]

The purpose of this note is to study the equivalence of observed and expected (Fisher) information functions with polytomous item response theory (IRT) models. It is established that observed and expected information functions are equivalent for the class of divide-by-total models (including partial credit, generalized partial credit, rating scale and nominal response models), but not for the class of difference models (including the graded response and modified graded response models). Yet, observed information function remains positive in both classes. Straightforward connections with dichotomous IRT models and further implications are outlined. [less ▲]

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See detailIsolating auroral FUV emission lines using compact, broadband instrumentation
Molyneux, P.M.; Bannister, N.P.; Bunce, E.J. et al

in Planetary and Space Science (in press)

Images of auroral emissions at far ultraviolet (FUV, 122–200 nm) wavelengths are useful tools with which to study magnetospheric-ionospheric coupling, as the scattered sunlight background in this region ... [more ▼]

Images of auroral emissions at far ultraviolet (FUV, 122–200 nm) wavelengths are useful tools with which to study magnetospheric-ionospheric coupling, as the scattered sunlight background in this region is low, allowing both dayside and nightside auroras to be imaged simultaneously. The ratio of intensities between certain FUV emission lines or regions can be used to characterise the precipitating particles responsible for auroral emissions, and hence is a useful diagnostic of magnetospheric dynamics. Here, we describe how the addition of simple transmission filters to a compact broadband imager design allows far ultraviolet emission ratios to be deduced while also providing large-scale instantaneous images of the aurora. The low mass and volume of such an instrument would make it well-suited for both small satellite Earth-orbiting missions and larger outer planet missions from which it could be used to characterise the tenuous atmospheres observed at several moons, as well as studying the auroral emissions of the gas giants. We present a study to investigate the accuracy of a technique to allow emission line ratio retrieval, as applied to the OI 130.4 nm and 135.6 nm emissions at Ganymede. The ratio of these emissions provides information about the atmospheric composition, specifically the relative abundances of O and O2. Using modelled FUV spectra representative of Ganymede's atmosphere, based on observations by the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS), we find that the accuracy of the retrieved ratios is a function of the magnitude of the ratio, with the best measurements corresponding to a ratio of ∼1.3 . [less ▲]

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See detailAdolescentes victimes d'abus sexuel et trajectoire délinquante : quels facteurs de résilience ?
Glowacz, Fabienne ULg; Buzitu, Rachel

in Neuropsychiatrie de l'enfance et de l'adolescence (in press)

Introduction: This study concerns resilience related to juvenile delinquency among victims of sexual abuse: sexual abuse has been recognized as a powerful risk factor for the emergence of deviant and ... [more ▼]

Introduction: This study concerns resilience related to juvenile delinquency among victims of sexual abuse: sexual abuse has been recognized as a powerful risk factor for the emergence of deviant and criminal behavior. Objective: Our study aims to explore and highlight the protective factors that prevent victims of sexual abuse from engaging in a delinquent trajectory. Method: The sample consists of teenage girls who have revealed at minimum last year, their intergenerational abuse. These girls, all between 12 and 18 years old, are divided into sub-groups: the non-offender victims and the victims who are also offenders. Each teenage victim is compared to a normative population on different psychological functioning dimensions : self-esteem (Harter's self-perception profile for adolescents), aggressiveness (the Buss-Perry Aggression questionnaire) and Post-Traumatic Stress, with the Impact of Event scale-Revised, (IES-R)-Horowitz. We analyze family characteristics such as familial attachment and family climate, social characteristics such as associations with peers, and environmental factors such as reactions to revelations of sexual abuse, the presence of family and extra-familial resources, psychological care. Results and conclusion: The results show that teenage victims of sexual assault present lower self-esteem and a negative self-perception in all fields, except for the perception of their attractiveness. Over-investment of this single dimension of self-perception can lead to a sexualization of their relationships with others and expose them to the risk of sexual revictimisation. The comparative analyses between the adolescent delinquent and non-delinquent victims highlight risk factors in connection with setting them off on a delinquent trajectory and protective factors supporting their resilience. The results highlight specific characteristics to the offender juvenile victims supporting a delinquent trajectory : aggressiveness, PTSD, defensive strategy of avoidance and characteristics of abuse (chronicity of abuse). The victim committed in delinquent trajectories presented more aggressiveness, consumeristic behaviour, post-traumatic stress and defensive strategy of avoidance than non-offender victims. Delinquent behaviour, just like substance abuse, could be a strategy of risk avoidance in connection with reliving sexual trauma, which hinders the process of resilience. Compared to the process of resilience, immediate and differed paternal support (during and after the revelations) seems the most important factor of protection. Being able to benefit from psychological councelling and having an extra-familial resource (a significant relationship with someone in the social environment) also constitute factors that support the resilience of these teenagers and prevent them from going down the path of delinquency. The interventions should aim at establishing a therapeutic alliance with these young girls during the early process of revealing the sexual abuse and mobilize and activate the support of the father (when he is not the abuser) or of a meaningful paternal figure as early as possible during the revealing phase and to accompany him in this restructuring function. [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 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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