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See detailTechnical Note: Large overestimation of pCO2 calculated from pH and alkalinity in acidic, organic-rich freshwaters
Abril, G; Bouillon, S; Darchambeau, François ULg et al

in Biogeosciences (2015), 12(1), 67-78

Inland waters have been recognized as a significant source of carbon dioxide (CO2) to the atmosphere at the global scale. Fluxes of CO2 between aquatic systems and the atmosphere are calculated from the ... [more ▼]

Inland waters have been recognized as a significant source of carbon dioxide (CO2) to the atmosphere at the global scale. Fluxes of CO2 between aquatic systems and the atmosphere are calculated from the gas transfer velocity and the water–air gradient of the partial pressure of CO2 (pCO2). Currently, direct measurements of water pCO2 remain scarce in freshwaters, and most published pCO2 data are calculated from temperature, pH and total alkalinity (TA). Here, we compare calculated (pH and TA) and measured (equilibrator and headspace) water pCO2 in a large array of temperate and tropical freshwaters. The 761 data points cover a wide range of values for TA (0 to 14 200 μmol L􀀀1), pH (3.94 to 9.17), measured pCO2 (36 to 23 000 ppmv), and dissolved organic carbon (DOC) (29 to 3970 μmol L􀀀1). Calculated pCO2 were >10% higher than measured pCO2 in 60% of the samples (with a median overestimation of calculated pCO2 compared to measured pCO2 of 2560 ppmv) and were >100% higher in the 25% most organic-rich and acidic samples (with a median overestimation of 9080 ppmv). We suggest these large overestimations of calculated pCO2 with respect to measured pCO2 are due to the combination of two cumulative effects: (1) a more significant contribution of organic acids anions to TA in waters with low carbonate alkalinity and high DOC concentrations; (2) a lower buffering capacity of the carbonate system at low pH, which increases the sensitivity of calculated pCO2 to TA in acidic and organicrich waters. No empirical relationship could be derived from our data set in order to correct calculated pCO2 for this bias. Owing to the widespread distribution of acidic, organic-rich freshwaters, we conclude that regional and global estimates of CO2 outgassing from freshwaters based on pH and TA data only are most likely overestimated, although the magnitude of the overestimation needs further quantitative analysis. Direct measurements of pCO2 are recommended in inland waters in general, and in particular in acidic, poorly buffered freshwaters [less ▲]

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See detailIntroduction
Fallon, Catherine ULg

in Albarello, Luc; Fallon, Catherine; Van Haeperen, Beatrice (Eds.) Evaluation des politiques publiques (2015)

Ce livre s’adresse à toutes les personnes qui a des titres divers sont concernés par l’évaluation des politiques publiques parce qu’ils doivent en assurer la réalisation ou en encadrer la démarche. Les ... [more ▼]

Ce livre s’adresse à toutes les personnes qui a des titres divers sont concernés par l’évaluation des politiques publiques parce qu’ils doivent en assurer la réalisation ou en encadrer la démarche. Les exemples et les angles de discussion sont les plus larges possibles pour que le lecteur puisse s’approprier les outils quel que soit son secteur de responsabilité et quel que soit son territoire. Il trouvera dans la suite des chapitres non pas un livre de recettes – ce qui nous semble contraire à la logique d’évaluation de politiques – mais des cadres de réflexion, des propositions de pratiques, ainsi que des références complémentaires pour développer ses pratiques tout en mobilisant un regard critique. [less ▲]

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See detailThe Cellobiose Sensor CebR is the Gatekeeper of Streptomyces scabies Pathogenicity
Francis, Isolde; Jourdan, Samuel ULg; Fanara, Steven ULg et al

in MBio (2015)

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See detailMagnetic shielding performances of YBa2Cu3O7−δ -coated silver tubes obtained by electrophoretic deposition
Devendra Kumar, N; Closset, Raphaël ULg; Wera, Laurent ULg et al

in Superconductor Science and Technology (2015), 28

We report a complete procedure to achieve multilayer YBCO thick films by electrophoretic deposition on silver tubes using a suspension of YBCO powder in butanol. With the aim to optimize the magnetic ... [more ▼]

We report a complete procedure to achieve multilayer YBCO thick films by electrophoretic deposition on silver tubes using a suspension of YBCO powder in butanol. With the aim to optimize the magnetic shielding performances of the coatings, we have carried out an extensive investigation of the influence of the deposition parameters, the multilayer deposition sequence and the intermediate/final heat treatments on the coating microstructure. Using the optimized conditions, a 24-layer YBCO coating has been successfully prepared on an 80 mm long Ag tube: the melt growth processed multilayered YBCO thick film thus obtained can shield an applied magnetic field of 1.9 mT at 77 K, the highest value per thickness unit reported so far in the literature for these materials. [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 (2015), 40

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 detailObjectivité et subjectivité dans la critique husserlienne du relativisme
Seron, Denis ULg

in Gyemant, Maria (Ed.) Psychologie et psychologisme (2015)

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See detailPrevalence and prognosis of Alzheimer’s disease at the mild cognitive impairment stage
Vos; VERHEY, F.; Frölich, L. et al

in Brain : A Journal of Neurology (2015)

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See detailSartre in Venedig: der Mann, der in die Kälte ging
Cormann, Grégory ULg; Viehöver, Vera ULg

in Bulletin d'Analyse Phénoménologique (2015), 11

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See detail"Passer la ligne" : La rencontre de Fanon et de Sartre
Cormann, Grégory ULg

in Luneau, Marie-Pier; Saint-Amand, Denis (Eds.) La Préface. Formes, enjeux et effets d’un discours d’escorte (2015)

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See detailLectures de La Reine Albemarle ou le dernier touriste. Ontologie, autobiographie, politique
Cormann, Grégory ULg

in Bulletin d'Analyse Phénoménologique (2015), 11(1),

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See detailAgeism and its clinical impact in oncogeriatry: state of knowledge and therapeutic leads
Schroyen, Sarah ULg; Adam, Stéphane ULg; JERUSALEM, Guy ULg et al

in Clinical Interventions in Aging (2015), 10

Cancer is a major health problem that is widespread in elderly people. Paradoxically, older people suffering from cancer are often excluded from clinical trials and are undertreated when compared to ... [more ▼]

Cancer is a major health problem that is widespread in elderly people. Paradoxically, older people suffering from cancer are often excluded from clinical trials and are undertreated when compared to younger patients. One explanation for these observations is age stigma (ie, stereotypes linked to age, and thus ageism). These stigmas can result in deleterious consequences for elderly people’s mental and physical health in “normal” aging. What, then, is the impact in a pathological context, such as oncology? Moreover, health care professionals’ attitudes can be tainted with ageism, thus leading to undesirable consequences for patients. To counter these stigmas, we can apply some possible interventions emerging from research on normal aging and from social psychology, such as intergenerational contact, activation of positive stereotypes, self-affirmation, and so on; these tools can improve opinions of aging among the elderly people themselves, as well as health care professionals, thus affecting patients’ mental and physical health. [less ▲]

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See detailMutations in the voltage-gated potassium channel gene KCNH1 cause Temple-Baraitser syndrome and epilepsy.
Simons, Cas; Rash, Lachlan D.; Crawford, Joanna et al

in Nature genetics (2015), 47(1), 73-7

Temple-Baraitser syndrome (TBS) is a multisystem developmental disorder characterized by intellectual disability, epilepsy, and hypoplasia or aplasia of the nails of the thumb and great toe. Here we ... [more ▼]

Temple-Baraitser syndrome (TBS) is a multisystem developmental disorder characterized by intellectual disability, epilepsy, and hypoplasia or aplasia of the nails of the thumb and great toe. Here we report damaging de novo mutations in KCNH1 (encoding a protein called ether a go-go, EAG1 or KV10.1), a voltage-gated potassium channel that is predominantly expressed in the central nervous system (CNS), in six individuals with TBS. Characterization of the mutant channels in both Xenopus laevis oocytes and human HEK293T cells showed a decreased threshold of activation and delayed deactivation, demonstrating that TBS-associated KCNH1 mutations lead to deleterious gain of function. Consistent with this result, we find that two mothers of children with TBS, who have epilepsy but are otherwise healthy, are low-level (10% and 27%) mosaic carriers of pathogenic KCNH1 mutations. Consistent with recent reports, this finding demonstrates that the etiology of many unresolved CNS disorders, including epilepsies, might be explained by pathogenic mosaic mutations. [less ▲]

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See detailLes supports pour l'étude fournis à l'élève en sciences biologiques sont-ils créateurs d'inégalités? Etude exploratoire de productions de futurs enseignants en Fédération Wallonie-Bruxelles (Belgique)
Poffé, Corentin ULg; Laschet, Mélanie ULg; Hindryckx, Marie-Noëlle ULg

in Spirale : Revue de Recherches en Education (2015), 55

Une revue de la littérature permet d’attribuer à de nombreux facteurs les inégalités dans l’apprentissage. Parmi ceux-ci, nous avons choisi d’analyser, avec le regard du formateur d’enseignants, les ... [more ▼]

Une revue de la littérature permet d’attribuer à de nombreux facteurs les inégalités dans l’apprentissage. Parmi ceux-ci, nous avons choisi d’analyser, avec le regard du formateur d’enseignants, les supports pour l’étude proposés par nos étudiants futurs enseignants aux élèves du secondaire (15 à 18 ans) en vue de l’évaluation, lors des cours de sciences biologiques. Cette « photographie instantanée » des supports pour l’étude nous a fourni un état des lieux qui nous permet d’objectiver nos impressions de formateurs quant au rôle des supports pour l’étude dans la problématique des inégalités scolaires. [less ▲]

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See detailEstetrol is a weak estrogen antagonizing estradiol-dependent mammary gland proliferation.
Gérard, Céline ULg; Blacher, Silvia ULg; Communal, Laudine et al

in Journal of Endocrinology (2015), 224(1), 86-95

Estetrol (E4) is a natural estrogen produced exclusively by the human fetal liver during pregnancy. Its physiological activity remains unknown. In contrast to ethinyl estradiol (EE) and estradiol (E2), E4 ... [more ▼]

Estetrol (E4) is a natural estrogen produced exclusively by the human fetal liver during pregnancy. Its physiological activity remains unknown. In contrast to ethinyl estradiol (EE) and estradiol (E2), E4 has a minimal impact on liver cells activity and could provide a better safety profile in contraception or hormone therapy. The aim of this study was to delineate if E4 exhibits an activity profile distinct from that of E2 on mammary gland. Compared to E2, E4 acted as a low affinity estrogen in both, human in vitro and murine in vivo, models. E4 was 100 times less potent than E2 to stimulate the proliferation of human breast epithelial (HBE) cells and murine mammary gland in vitro and in vivo, respectively. This effect was prevented by fulvestrant and by tamoxifen supporting the notion that ERalpha is the main mediator of the estrogenic effect of E4 on the breast. Interestingly, when E4 was administered along with E2, it significantly antagonized the strong stimulatory effect of E2 on HBE cells proliferation and on the growth of mammary ducts. This study characterizes for the first time the impact of E4 on mammary gland. Our results highlight that E4 is less potent than E2 and exhibits antagonistic properties towards the proliferative effect of E2 on breast epithelial cells. These data support E4 as a potential new estrogen for clinical use with a reduced impact on breast proliferation. [less ▲]

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See detailDoes reward unpredictability reflect risk?
Anselme, Patrick ULg

in Behavioural Brain Research (2015), 280(1), 119-127

Most decisions made in real-life situations are risky because they are associated with possible negative consequences. Current models of decision-making postulate that the occasional, unpredictable ... [more ▼]

Most decisions made in real-life situations are risky because they are associated with possible negative consequences. Current models of decision-making postulate that the occasional, unpredictable absence of reward that may result from free choice is a negative consequence interpreted as risk by organisms in laboratory situations. I argue that such a view is difficult to justify because, in most experimental paradigms, reward omission does not represent a cost for the decision maker. Risk only exists when unpredictability may cause a potential loss of own limited resources, whether energetic, social, financial, and so on. Thus the experimental methodologies used to test humans and non-humans relative to risk-taking seem to be limited to studying the effects of reward uncertainty in the absence of true decision cost. This may have important implications for the conclusions that can be drawn with respect to the neurobehavioural determinants of risk-taking in real-life situations. [less ▲]

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See detailFe–Ti–V–P ore deposits associated with Proterozoic massif-type anorthosites and related rocks
Charlier, Bernard ULg; Namur, Olivier; Bolle, Olivier ULg et al

in Earth-Science Reviews (2015), 141(0), 56-81

Magmatic rocks containing economic concentrations of iron, titanium, vanadium and phosphorous are commonly associated with massif-type anorthosites and related rocks. This rock association is part of the ... [more ▼]

Magmatic rocks containing economic concentrations of iron, titanium, vanadium and phosphorous are commonly associated with massif-type anorthosites and related rocks. This rock association is part of the anorthosite–mangerite–charnockite–(rapakivi-)granite suites that are restricted to the Proterozoic. Understanding the geochemistry and emplacement mechanisms of ilmenite, magnetite and apatite ore deposits is crucial for exploration, efficient mining operations and ore processing. This review discusses the controlling factors on the grade of an ore, its mineralogy, and its major and trace element distribution. We present petrogenetic models of currently mined deposits (Lac Tio, Tellnes, Damiao) and discuss the characteristics of minor ore bodies from anorthosite provinces worldwide (Grenville, North China Craton, East European Craton, Rogaland, Laramie). Models of formation of anorthosite and related rocks are presented, as well as the nature of the possible parental magmas of the suite. A mineralogical classification of Fe–Ti ores is proposed: (1) Gabbro-noritic ilmenite ore ± apatite ± magnetite; (2) Ti-magnetite-dominated ore; (3) Nelsonite (Fe–Ti oxides + apatite); and (4) Rutile-ilmenite ore. The stability of ilmenite and magnetite is then critically reviewed and the influence of various factors, particularly oxygen fugacity and crystallization pressure, is examined. We discuss liquidus compositions of Fe–Ti oxides and the behavior of important trace elements such as Cr and V, both of which are sensitive to fO2 variations. Post-cumulus evolution of both oxides can occur due to re-equilibration with trapped liquid, re-equilibration with ferromagnesian silicates, exsolution, oxidation, reaction between ilmenite and magnetite, and metamorphic overprinting. These various processes are described and their effects on the oxide geochemistry are emphasized. Several potential ore-forming processes have been invoked and can explain the formation of huge concentration of ilmenite, ± magnetite, ± apatite. Fractional crystallization can be combined with crystal sorting and plagioclase buoyancy to produce relative enrichment of dense ore minerals. Silicate liquid immiscibility can segregate conjugate Si-rich and Fe-rich melts, the latter being enriched in Fe–Ti–P. Magma mixing can produce hybrid magmas located in a single-phase field of the phase diagram and precipitate a pure ilmenite cumulate. Alternative processes are also described, such as ejection of Fe–Ti-enriched residual melts by filter-pressing and compaction, solid-state remobilization of ilmenite in veins, and hydrothermal transport of Fe and Ti from the host anorthosite followed by concentration in veins and lenticular ore bodies. The magnetic properties of Fe–Ti ore deposits present contrasting signatures, depending on whether the natural remanent magnetization is dominated by hemo-ilmenite or multi-domain magnetite. Micro- and macro-scale deformation features of ore rocks are intimately correlated with magma emplacement, and with ballooning of the anorthosite diapir associated with gravitational sagging of dense ore bodies. Exploration perspectives show that oxide-apatite gabbronorites are interesting targets because ilmenite in these rocks is poorer in Cr and Mg, and because the Ti-resource may be combined with apatite and vanadiferous magnetite. [less ▲]

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See detailA branch-and-price algorithm for 2-period vehicle routing problems
Crama, Yves ULg; Rezaei Sadrabadi, Mahmood ULg; Van Woensel, Tom

E-print/Working paper (2015)

We consider a Vehicle Routing Problem (VRP) with deterministic orders in two periods from a set of stores. Orders in period 1 (2) can be postponed (advanced) to the other period but any diversion from the ... [more ▼]

We consider a Vehicle Routing Problem (VRP) with deterministic orders in two periods from a set of stores. Orders in period 1 (2) can be postponed (advanced) to the other period but any diversion from the initial orders incurs a penalty. From the perspective of a Logistics Service Provider (LSP), such diversions could be beneficial if savings in the routing costs outweigh the penalties. So could they be from a store's view, as the store can set a high enough penalty to compensate the diversion from its own optimal orders. In this paper, we introduce a new model where we seek a better solution for the LSP, compared to solving two independent VRPs with fixed orders, by allowing orders to be fully postponed or advanced. We apply a branch-and-price algorithm to solve this model to optimality. Many cutting-edge techniques are implemented to have an efficient branch-and-price algorithm, and two ideas to possibly improve the upper bound are tested. We draw algorithmic and managerial insights based on our test instances. [less ▲]

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See detailSartre et l'instinct de mort
Cormann, Grégory ULg

in Gyemant, Maria; Popa, Delia (Eds.) Approches phénoménologiques de l'inconscient (2015)

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See detailCompte-rendu de l'ouvrage de M. Le Blanc et P. Trudeau: La réadaptation de l'adolescent antisocial
Mathys, Cécile ULg

in Canadian Journal of Criminology & Criminal Justice = Revue Canadienne de Criminologie et de Justice Pénale (2015), 57(1),

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See detailMutation de l'image, mutation de l'intention ? L'impact des représentations architecturales
Cunin, Maxime; Yang, Maria C.; Elsen, Catherine ULg

in de Boissieu, Aurélie; Deshayes, Catherine (Eds.) Actes du colloque "Mutations du Projet - Milieux et Cultures Numériques" (2015)

Les architectes ont toujours eu recours à de multiples représentations pour générer, faire évoluer puis communiquer leurs concepts architecturaux (tant aux pairs qu’aux usagers, ou encore aux décideurs ... [more ▼]

Les architectes ont toujours eu recours à de multiples représentations pour générer, faire évoluer puis communiquer leurs concepts architecturaux (tant aux pairs qu’aux usagers, ou encore aux décideurs). Cet article envisage comment la représentation externe impacte la perception « naïve » d’une intention architecturale, les « non experts » assumant des rôles de plus fondamentaux au sein de certains mécanismes décisionnels. Comment l’image, en pleine mutation depuis l’ère du numérique, façonne-t-elle la perception des facteurs clés (ou « attributs ») d’une intention architecturale ? L’article résume les principaux résultats d’une enquête menée en ligne via l’interface « Amazon Mechanical Turk » et générant 790 échelles d’évaluation de 6 avant-projets architecturaux. Les résultats abordent l’analyse des données en regard des différentes attributs; en regard des trois types de représentation choisies et en regard enfin des inconsistances dont font preuve les architectes eux-mêmes, étant donné l’évaluation de leurs propres projets et représentations. Ils révèlent que les attributs ne sont pas équitablement propices à un transfert d’intention exclusivement graphique et que les formes plus abstraites de représentations constituent, dans certains contextes, le moyen le plus efficace pour le transfert fidèle d’une intention architecturale. [less ▲]

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