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See detailRadio-frequency magnetron sputtering: a versatile tool for CdSe quantum dots depositions with controlled properties
Dahi, Abdellatif; Colson, Pierre ULg; Jamin, Claire et al

in Journal of Material and Environmental Sciences (2016), 7(7), 2277-2287

CdSe nanoparticles are of great interest for many applications. However, their size, shape, and aggregation are still difficult to control by the conventional synthesis methods. Here, we report on the ... [more ▼]

CdSe nanoparticles are of great interest for many applications. However, their size, shape, and aggregation are still difficult to control by the conventional synthesis methods. Here, we report on the synthesis of CdSe quantum dots (QDs), with an average diameter less than 10 nm, using radio-frequency magnetron sputtering (RFMS) on glass and silicon substrates at 25 °C. First, results show that a target-substrate distance of 13.5 cm and a chamber pressure of 2.2 .10-1 mbar were required to deposit a CdSe QDs layer on the substrates. The morphology and optical properties of CdSe QDs were then studied as a function of RF power and deposition time. The size of CdSe QDs increases with increasing both the RF power and the deposition time. UV-visible spectroscopy shows that the CdSe QDs layer deposited on the glass-substrate by RFMS has almost the same optical properties as the one obtained from commercial CdSe QDs solutions. In both cases, a shift of the characteristic absorption band of CdSe QDs towards the higher wavenumbers is observed with the QDs size increase. AFM confirms the success of CdSe QDs layer deposition by RFMS: CdSe QDs with a mean diameter of 7.5 ± 2 nm were observed for a RF power of 14 W, a chamber pressure of 2.2 .10-1 mbar, a target-substrate distance of 13.5 cm and a deposition time of 7.5 min (optimal values). With these parameters, the coverage of the substrate by the nano-objects is estimated at 25-30 % of the overall surface. [less ▲]

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See detailDes situations-limites au dépassement de la situation : phénoménologie d'un concept sartrien
Cormann, Grégory ULg; Englebert, Jérôme ULg

in Sartre Studies International (2016), 22(1),

Dans cet article, nous explorons le concept de situation, en-deçà et au-delà de sa thématisation par Sartre, à partir de L’imaginaire, dans les Carnets de la drôle de guerre puis dans L’être et le néant ... [more ▼]

Dans cet article, nous explorons le concept de situation, en-deçà et au-delà de sa thématisation par Sartre, à partir de L’imaginaire, dans les Carnets de la drôle de guerre puis dans L’être et le néant. Notre approche se fonde sur un double mouvement : d’une part, une archéologie du concept dans le contexte de la première percée de la phénoménologie en France dans les années 1930 ; d’autre part, une attention à son possible dépassement deux décennies plus tard. Dans une relation serrée avec les développements de la psychopathologie de son temps, il s’agit d’abord de situer la prétention de l’Esquisse d’une théorie des émotions à poser les bases d’une phénoménologie de « l’homme en situation », ensuite d’éclairer la reprise critique du concept dans Questions de méthode, dans l’exposition de la méthode progressive-régressive. En somme, il s’agit de montrer comment s’élabore progressivement chez Sartre une « herméneutique de l’existence » qui fait droit à la liberté, puis se donne les moyens d’en suivre l’action effective dans le monde. [less ▲]

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See detailOnline Learning for Strong Branching Approximation in Branch-and-Bound
Marcos Alvarez, Alejandro ULg; Wehenkel, Louis ULg; Louveaux, Quentin ULg

E-print/Working paper (2016)

We present an online learning approach to variable branching in branch-and-bound for mixed-integer linear problems. Our approach consists in learning strong branching scores in an online fashion and in ... [more ▼]

We present an online learning approach to variable branching in branch-and-bound for mixed-integer linear problems. Our approach consists in learning strong branching scores in an online fashion and in using them to take branching decisions. More specifically, numerical scores are used to rank the branching candidates. If, for a given variable, the learned approximation is deemed reliable, then the score for that variable is computed thanks to the learned function. If the approximation is not reliable yet, the real strong branching score is used instead. The scores that are computed through the real strong branching procedure are fed to the online learning algorithm in order to improve the approximated function. The experiments show promising results. [less ▲]

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See detailAn Improved Molecular Histology Method for Ion Suppression Monitoring and Quantification of Phosphatidyl Cholines During MALDI MSI Lipidomics Analyses.
Jadoul, Laure ULg; Smargiasso, Nicolas ULg; Pamelard, Fabien et al

in OMICS : A Journal of Integrative Biology (2016), 20(2), 110-21

Tissue lipidomics is one of the latest omics approaches for biomarker discovery in pharmacology, pathology, and the life sciences at large. In this context, matrix-assisted laser desorption/ionization ... [more ▼]

Tissue lipidomics is one of the latest omics approaches for biomarker discovery in pharmacology, pathology, and the life sciences at large. In this context, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is the most versatile tool to map compounds within tissue sections. However, ion suppression events occurring during MALDI MSI analyses make it impossible to use this method for quantitative investigations without additional validation steps. This is especially true for lipidomics, since different lipid classes are responsible for important ion suppression events. We propose here an improved lipidomics method to assess local ion suppression of phospatidylcholines in tissues. Serial tissue sections were spiked with different amounts of PC(16:0 d31/18:1) using a nebulization device. Settings for standard nebulization were strictly controlled for a detection similar to when using spiked tissue homogenates. The sections were simultaneously analyzed by MALDI MSI using a Fourier transform ion cyclotron resonance analyzer. Such a spray-based approach allows taking into account the biochemical heterogeneity of the tissue for the detection of PC(16:0 d31/18:1). Thus, here we present the perspective to use this method for quantification purposes. The linear regression lines are considered as calibration curves and we calculate PC(16:0/18:1) quantification values for different ROIs. Although those values need to be validated by a using a different independent approach, the workflow offers an insight into new quantitative mass spectrometry imaging (q-MSI) methods. This approach of ion suppression monitoring of phosphocholines in tissues may be highly interesting for a large range of applications in MALDI MSI, particularly for pathology using translational science workflows. [less ▲]

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See detailLe questeur et le gouverneur : quelques réflexions sur les deux derniers siècles de la République
Ioannidopoulos, Grégory ULg

Scientific conference (2016)

Tout au long de la République, dès lors qu’un magistrat titulaire de l’imperium quittait Rome chargé d’une mission officielle, un questeur lui était constamment adjoint. Celui-ci avait pour tâche de ... [more ▼]

Tout au long de la République, dès lors qu’un magistrat titulaire de l’imperium quittait Rome chargé d’une mission officielle, un questeur lui était constamment adjoint. Celui-ci avait pour tâche de prendre en charge les aspects financiers de la mission confiée à son supérieur : distribution de la solde, gestion des fournitures et des approvisionnements de l’armée, rédaction et conservation des comptes, etc. Le questeur avait en réalité un rôle autrement plus important que celui de trésorier, auquel il est communément cantonné : outre ces missions d’ordre pécuniaire, il était en effet le bras-droit du général/gouverneur, son commandant-en-second, chargé d’une partie des troupes ou de rendre la justice, et même appelé à le remplacer à la tête de son armée ou de sa province en cas d’indisponibilité. Cette relation, faite de subordination et, paradoxalement, d’une forme de parité, trouve bien sûr son origine dans le possible empêchement du magistrat supérieur (mort, départ) qu’il fallait pallier, mais aussi dans le caractère oligarchique du système politique romain : les questeurs, élus certes par le peuple, étaient généralement issus du groupe réduit de l’aristocratie. Et au sein de ce groupe, dont venaient l’immense majorité de leurs supérieurs eux aussi, c’était le tirage au sort, 'inter pares', qui déterminait sous les ordres de qui ils serviraient. En raison de cette familiarité de tous les instants, un lien particulier unissait le questeur et son supérieur, ces deux étrangers unis par la sors, lien théorisé par Cicéron sous le nom de 'necessitudo'. Celle-ci nécessitait cependant une grande confiance entre les deux protagonistes : les luttes politiques devenues guerres civiles, les ressentiments qui en naquirent, et l’émergence de personnalités fortes ébranlèrent ce modèle. Et l’usage d’assigner les questeurs 'extra sortem' à la discrétion de ceux qui les emploieraient, devint une constante au profit des 'imperatores' de la fin de la République. [less ▲]

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See detailDifferential Acute Impacts of Sleeve Gastrectomy, Roux-en-Y Gastric Bypass Surgery and Matched Caloric Restriction Diet on Insulin Secretion, Insulin Effectiveness and Non-Esterified Fatty Acid Levels Among Patients with Type 2 Diabetes.
Thomas, Felicity Louise ULg; Smith, Greg C.; Lu, Jun et al

in Obesity surgery (2016)

BACKGROUND: Bariatric surgery is an increasingly common option for control of type 2 diabetes (T2D) and obesity. Mechanisms underlying rapid improvement of T2D after different types of bariatric surgery ... [more ▼]

BACKGROUND: Bariatric surgery is an increasingly common option for control of type 2 diabetes (T2D) and obesity. Mechanisms underlying rapid improvement of T2D after different types of bariatric surgery are not clear. Caloric deprivation and altered levels of non-esterified fatty acid (NEFA) have been proposed. This study examines how sleeve gastrectomy (SG), Roux-en-Y gastric bypass (GBP) or matched hypocaloric diet (DT) achieves improvements in T2D by characterising components of the glucose metabolism and NEFA levels before and 3 days after each intervention. METHODS: Plasma samples at five time points during oral glucose tolerance test (OGTT) from subjects with T2D undergoing GBP (N = 11) or SG (N = 12) were analysed for C-peptide, insulin and glucose before surgery and 3-day post-intervention or after DT (N = 5). Fasting palmitic, linoleic, oleic and stearic acid were measured. C-peptide measurements were used to model insulin secretion rate (ISR) using deconvolution. RESULTS: Subjects who underwent GBP surgery experienced the greatest improvement in glycaemia (median reduction in blood glucose (BG) from basal by 29 % [IQR -57, -18]) and the greatest reduction in all NEFA measured. SG achieved improvement in glycaemia with lower ISR and reduction in all but palmitoleic acid. DT subjects achieved improvement in glycaemia with an increase in ISR, 105 % [IQR, 20, 220] and stearic acid. CONCLUSIONS: GBP, SG and DT each improve glucose metabolism through different effects on pancreatic beta cell function, insulin sensitivity and free fatty acids. [less ▲]

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See detailTransient performance evaluation of waste heat recovery Rankine cycle based system for heavy duty trucks
Grelet, Vincent; Reiche, Thomas; Lemort, Vincent ULg et al

in Applied Energy (2016)

The study presented in this paper aims to evaluate the transient performance of a waste heat recovery Rankine cycle based system for a heavy duty truck and compare it to steady state evaluation. Assuming ... [more ▼]

The study presented in this paper aims to evaluate the transient performance of a waste heat recovery Rankine cycle based system for a heavy duty truck and compare it to steady state evaluation. Assuming some conditions to hold, simple thermodynamic simulations are carried out for the comparison of several fluids. Then a detailed rst principle based model is also presented. Last part is focused on the Rankine cycle arrangement choice by means of model based evaluation of fuel economy for each concept where the fuels savings are computed using two methodologies. Fluid choice and concept optimization are conducted taking into account integration constraints (heat rejection, packaging . . . ). This paper shows the importance of the modeling phase when designing WHRS and yields a better understanding when it comes to a vehicle integration of a Rankine cycle in a truck. [less ▲]

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See detailLa médiation animale comme dispositif technique
de Villers Grand Champs, Bénédicte ULg; Servais, Véronique ULg

in Servais, Christine (Ed.) La médiation. De la théorie aux terrains (2016)

Les pratiques thérapeutiques associant des animaux sont-elles des techniques thérapeutiques comme les autres ? Quelles sont les particularités de cette « médiation animale » dès lors que l’agent médiateur ... [more ▼]

Les pratiques thérapeutiques associant des animaux sont-elles des techniques thérapeutiques comme les autres ? Quelles sont les particularités de cette « médiation animale » dès lors que l’agent médiateur, l’animal, est vivant et partiellement ignorant du dispositif dans lequel il est inscrit ? Nous faisons ici l’hypothèse que les pratiques de médiation animale peuvent s’inscrire dans l’horizon de ce que Leroi-Gourhan nommait le « milieu technique », le « mi-lieu », cet entre-deux qui assure la rencontre, la mise en relation d’un vivant et de son monde. Ce mi-lieu n’a rien d’un cordon, même symbolique, qui relierait le patient, l’intervenant et l’animal. Il se présente plutôt sous la forme d’un écotone, du nom des écosystèmes qui se développent à la lisière de deux écosystèmes différents et dont l’écosystème côtier est le meilleur exemple. Nous nous appuyons sur les concepts de technique, de technique du corps, d’espace potentiel et de rituel pour essayer de comprendre ce processus de médiation dont un vivant animal est partie prenante et comment il se fait que des rencontres animales recèlent un potentiel thérapeutique [less ▲]

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See detailProcedural learning, consolidation, and transfer of a new skill in Developmental Coordination Disorder
Lejeune, Caroline ULg; Wansard, Murielle ULg; Geurten, Marie ULg et al

in Child Neuropsychology : A Journal on Normal & Abnormal Development in Childhood & Adolescence (2016), 22(2),

The aim of this study was to explore the differences in procedural learning abilities between children with DCD and typically developing children by investigating the steps that lead to skill ... [more ▼]

The aim of this study was to explore the differences in procedural learning abilities between children with DCD and typically developing children by investigating the steps that lead to skill automatization (i.e., the stages of fast learning, consolidation, and slow learning). Transfer of the skill to a new situation was also assessed. We tested 34 children aged 6–12 years with and without DCD on a perceptuomotor adaptation task, a form of procedural learning that is thought to involve the cerebellum and the basal ganglia (regions whose impairment has been associated with DCD) but also other brain areas including frontal regions. The results showed similar rates of learning, consolidation, and transfer in DCD and control children. However, the DCD children's performance remained slower than that of controls throughout the procedural task and they reached a lower asymptotic performance level; the difficulties observed at the outset did not diminish with practice. [less ▲]

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See detailAirewater interfacial properties of enzymatic wheat gluten hydrolyzates determine their foaming behavior
Wouters, Arno G.B.; Rombouts, Ine; Legein, Marie et al

in Food Hydrocolloids (2016), 55

Insight in the link between foaming and interfacial properties of proteins can increase their potential as functional agents in food systems. Here, foaming capacity and stability of structurally different ... [more ▼]

Insight in the link between foaming and interfacial properties of proteins can increase their potential as functional agents in food systems. Here, foaming capacity and stability of structurally different peptic and tryptic wheat gluten hydrolyzates were related to the kinetics of their adsorption at an airewater interface as well as to the properties of a compressed protein film at this interface. Foams from degree of hydrolysis (DH, i.e. the percentage of cleaved peptide bonds) 2 hydrolyzates were more stable than those from their DH 6 counterparts, and this at all protein concentrations tested. However, at protein concentrations from 0.010% to 0.050% (wprot/v), peptic DH 2 and 6 hydrolyzates had better foaming stability than their tryptic counterparts of the same DH. The opposite was observed when protein concentrations ranged from 0.050% to 0.150% (wprot/v). These observations can in part be explained by the molecular mass composition of the samples and, more importantly, by high levels of hydrophobic peptides in the DH 2 samples. The calculation of an average elasticity (up to 20e25 mN/m) from the variation in surface pressure for a variation in surface area in Langmuir isotherms showed that DH 2 samples had higher elasticity than DH 6 samples, which was in agreement with their foaming stabilities at various protein concentrations. Additionally, although not usually considered in literature, it seemed there was a correspondence between surface pressure at different protein surface concentrations and foaming stability at different protein concentrations. [less ▲]

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See detailThe Future of Ageing - Stakeholder Involvement on the Future of Care
Barland, Marianne; Delvenne, Pierre ULg; Rosskamp, Benedikt ULg

in Klüver, Lars; Øjvind Nielsen, Rasmus; Jørgensen, Marie Louise (Eds.) Policy-Oriented Technology Assessment Across Europe: Expanding Capacities (2016)

Barland et al. describe an example project showcasing the strengths of technology assessment methodology in structuring stakeholder dialogues in a cross-European context. The authors provide an in-depth ... [more ▼]

Barland et al. describe an example project showcasing the strengths of technology assessment methodology in structuring stakeholder dialogues in a cross-European context. The authors provide an in-depth account of the method design choices made and their underlying rationale. Beyond the buzzword, well-structured and transparent stakeholder dialogue can help to balance difficult issues of policy priority – in this case by balancing the contributions of technological innovation against social reorganization as a means of securing sustainable future health-care service for senior citizens. The article shows the added value of multi-site dialogues based in national debates but linked to the European policy development process [less ▲]

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See detailMaking Technology Assessment Accessible to New Players
Delvenne, Pierre ULg; Rosskamp, Benedikt ULg; Fitzgerald, Ciara et al

in Klüver, Lars; Nielsen, Rasmus; Jorgensen, Marie-Louise (Eds.) Policy-Oriented Technology Assessment Across Europe. Expanding Capacities (2016)

This chapter reports on the two PACITA summers schools, which were aimed at teaching TA as well as enhancing mutual-learning activities. The first summer school concentrated on the topic ‘Renewable Energy ... [more ▼]

This chapter reports on the two PACITA summers schools, which were aimed at teaching TA as well as enhancing mutual-learning activities. The first summer school concentrated on the topic ‘Renewable Energy Systems- role and use of PTA’ and it was held in Liege in June 2012. The second summer school addressed the topic of ‘Ageing and Technology’, and was held in Cork in June 2014. We describe the rationale and format of the summer school in order to present a comprehensive account of how it was introduced TA, both its rational and its methods, to a new audience. We argue that as the responsible innovation agenda continues to gain traction among policy makers, societal actors and academics, education initiatives such as TA summer schools can have an important role to play in the future of the governance of science, technology and innovation. [less ▲]

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See detailNeural Activation During Mental Rotation in Complete Androgen Insensitivity Syndrome: the Influence of Sex Hormones and Sex Chromosomes.
van Hemmen, Judy; Veltman, Dick J.; Hoekzema, Elseline et al

in Cerebral Cortex (2016)

Sex hormones, androgens in particular, are hypothesized to play a key role in the sexual differentiation of the human brain. However, possible direct effects of the sex chromosomes, that is, XX or XY ... [more ▼]

Sex hormones, androgens in particular, are hypothesized to play a key role in the sexual differentiation of the human brain. However, possible direct effects of the sex chromosomes, that is, XX or XY, have not been well studied in humans. Individuals with complete androgen insensitivity syndrome (CAIS), who have a 46,XY karyotype but a female phenotype due to a complete androgen resistance, enable us to study the separate effects of gonadal hormones versus sex chromosomes on neural sex differences. Therefore, in the present study, we compared 46,XY men (n = 30) and 46,XX women (n = 29) to 46,XY individuals with CAIS (n = 21) on a mental rotation task using functional magnetic resonance imaging. Previously reported sex differences in neural activation during mental rotation were replicated in the control groups, with control men showing more activation in the inferior parietal lobe than control women. Individuals with CAIS showed a female-like neural activation pattern in the parietal lobe, indicating feminization of the brain in CAIS. Furthermore, this first neuroimaging study in individuals with CAIS provides evidence that sex differences in regional brain function during mental rotation are most likely not directly driven by genetic sex, but rather reflect gonadal hormone exposure. [less ▲]

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See detailThe Fractal Nature of Mars Topography Analyzed via the Wavelet Leaders Method
Kleyntssens, Thomas ULg; Deliège, Adrien ULg; Nicolay, Samuel ULg

Poster (2016)

This work studies the scaling properties of Mars topography based on Mars Orbiter Laser Altimeter (MOLA) data through the wavelet leaders method (WLM). This approach shows a scale break at 15 km. At small ... [more ▼]

This work studies the scaling properties of Mars topography based on Mars Orbiter Laser Altimeter (MOLA) data through the wavelet leaders method (WLM). This approach shows a scale break at 15 km. At small scales, these topographic profiles display a monofractal behavior while a multifractal nature is observed at large scales. The scaling exponents are greater at small scales. They also seem to be influenced by latitude and may indicate a slight anisotropy in topography. [less ▲]

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See detailForeign Language Teachers’ Assessment Practices in French-Speaking Belgium’s Upper Secondary Schools: A Case Study
Noiroux, Kevin ULg

in The International Journal of Pedagogy and Curriculum (2016), 23(2),

Foreign language classroom assessment practices are a mystery, at least in Belgium. The present case study aims at shedding light on Belgian foreign languages teachers’ assessment practices in secondary ... [more ▼]

Foreign language classroom assessment practices are a mystery, at least in Belgium. The present case study aims at shedding light on Belgian foreign languages teachers’ assessment practices in secondary education. I interviewed seven teachers to know what they assessed and how often they assessed it. I also analyzed the legal provisions that teachers have to respect when they assess. The results show that teachers assess four communicative skills—listening, reading, writing, and speaking—as legally required, but also reveal that they frequently assess vocabulary and grammar, sometimes in ways that are not permitted. Furthermore, they spend a considerable amount of time assessing those skills without even being aware of it. Since these assessments only aim at verifying that the students master the skills, it may be worth investigating whether some assessments are not redundant so as to devote that time to a more productive task. [less ▲]

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See detailMechanoreceptors in the anterior horn of the equine medial meniscus: an immunohistochemical approach
Nemery, Elodie ULg; Gabriel, Annick ULg; Grulke, Sigrid ULg et al

in Anatomia, Histologia, Embryologia (2016), 45

Lameness due to stifle and especially meniscal lesions is frequent in equine species. In humans, mechanoreceptors involved in proprioceptive function are well studied. Given the high incidence of meniscal ... [more ▼]

Lameness due to stifle and especially meniscal lesions is frequent in equine species. In humans, mechanoreceptors involved in proprioceptive function are well studied. Given the high incidence of meniscal injuries in horses, and the lack of information concerning them in equine menisci, our objective was to study these corpuscles in six healthy anterior horns of the equine medial meniscus, which is the most common localisation reported for equine meniscal injuries. Immunohistochemical stainings were performed using antibodies against high molecular weight neurofilaments and glial fibrillary acidic proteins. From a purely fundamental point of view, our work highlights for the first time the presence of Ruffini, Pacini and Golgi corpuscles in equine meniscus. They were found, isolated or in clusters and always located at the vicinity of blood vessels, at the level of the anterior horn of the equine medial meniscus. This morphological approach could serve as a basis for clinical studies, to evaluate the impact of these corpuscles on the poor sportive prognosis in equine meniscal tears. [less ▲]

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