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See detailConstraining model biases in a global general circulation model with ensemble data assimilation methods
Canter, Martin ULg

Doctoral thesis (2017)

A new method of bias correction using an ensemble transform Kalman filter as data assimilation scheme is developed. The objective is to create a stochastic forcing term which will partially remove the ... [more ▼]

A new method of bias correction using an ensemble transform Kalman filter as data assimilation scheme is developed. The objective is to create a stochastic forcing term which will partially remove the bias from numerical models. The forcing term is considered as a parameter to be estimated through state vector augmentation and the assimilation of observations. The theoretical formulation of this method is introduced in the general context of numerical modelling. A specially designed and modified Lorenz '96 model is studied, and provides a testing environment for this new bias correction method. Several different aspects are considered through both single and iterative assimilation in a twin experiment. The method is then implemented on the global general circulation model of the ocean NEMO-LIM2. The forcing term generation is detailed to respect particular physical constraints. Again, a twin experiment allows to assess the efficiency of the method on a realistic model. The assimilation of sea surface height observations is performed, with sea surface salinity and temperature as control variable. Subsequently, a multivariate assimilation shows further improvement of the bias correction. Finally, the method is confronted to real sea surface height observations from the CNES-CLS09 global mean dynamic topography. A thorough study of the NEMO-LIM2 model response to the bias correction forcing term is proposed, and specific results are highlighted. An iterative assimilation concludes the method investigation. Possible ideas and future developments are suggested. [less ▲]

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See detailPapillomaviruses and cervical neoplasia
Herfs, Michael ULg; Chang, Martin; Crum, Christopher

in Holland-Frei Cancer Medicine, ninth edition (2017)

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See detailL'énonciation vidéoludique : analyse du jeu Portal
Barnabé, Fanny ULg

in Dondero, Maria Giulia; Beyaert-Geslin, Anne; Moutat, Audrey (Eds.) Les plis du visuel. Réflexivité et énonciation dans l'image (2017)

Si la sémiotique visuelle a aujourd’hui largement exploré bon nombre de domaines, le jeu vidéo demeure un champ relativement peu étudié via cette approche. Il constitue, en ce sens, un objet à la fois ... [more ▼]

Si la sémiotique visuelle a aujourd’hui largement exploré bon nombre de domaines, le jeu vidéo demeure un champ relativement peu étudié via cette approche. Il constitue, en ce sens, un objet à la fois problématique (car l’application des concepts développés pour les autres types d’images risque parfois de mener à des impasses) et potentiellement fécond (car il permet de tester ces mêmes concepts sur un objet qui leur résiste et éventuellement d’ouvrir de nouvelles perspectives). La question de l’énonciation vidéoludique, par contre, suscite déjà l’intérêt : différents chercheurs tels que Genvo (2008), Mabillot (2001), Amato (2005), Mpondo-Dicka (2005) ou Nélide-Mouniapin (2005) ont, en effet, déjà soulevé cette problématique. Néanmoins, celle-ci est rarement abordée sous l’angle de la sémiotique visuelle. La nouveauté du sujet implique donc que l’analyse que nous proposerons ici, loin d’être un état des lieux complet et abouti, aura plutôt pour objectif d’ouvrir le champ de la réflexion et de proposer des pistes d’interrogation pour aborder ce système sémiotique complexe qu’est le jeu vidéo. Malgré tout, dans le but d’asseoir nos observations sur des bases concrètes, nous nous intéresserons à une œuvre vidéoludique particulière : le jeu de réflexion Portal, développé en 2007 par Valve Corporation. [less ▲]

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See detailFlavor profiles of monovarietal virgin olive oils produced in the Oriental region of Morocco
Mansouri, Farid; Ben Moumen, Abdessamad; Richard, Gaetan ULg et al

in Oilseeds and fats, Crops and Lipids (2017), 24

The purpose of this study is the evaluation of flavor profiles of monovarietal virgin olive oils (VOO) produced in the Oriental region of Morocco via the characterization of volatile compounds, using SPME ... [more ▼]

The purpose of this study is the evaluation of flavor profiles of monovarietal virgin olive oils (VOO) produced in the Oriental region of Morocco via the characterization of volatile compounds, using SPME-GC/MS technique, and the determination of total phenolic content (colorimetric method). The study concerns oils of three European olive cultivars (Arbosana, Arbequina and Koroneiki) which were recently introduced in Morocco under irrigated high-density plantation system. GC/MS aroma profiles of analyzed VOOs showed the presence of 35 volatile compounds. The major compounds in such oils are C6 compounds produced from linoleic and linolenic acids via lipoxygenase pathway such as trans-2-hexenal, cis-2-hexenal, cis-3-hexen-1-ol, trans-3-hexen-1-ol, trans-3-hexen-1-ol acetate, hexanal and 1-hexanol in different proportions depending on the cultivar (p<0.05). In addition, statistical analyses indicate that the analyzed VOOs have different aroma profiles. Arbequina oil has a high proportion of compounds with sensory notes “green” and “sweet” giving it a fruity sensation compared to Arbosana and Koroneiki. In parallel, Arbosana and Koroneiki oils are rich in phenolic compounds and provide relatively bitter and pungent tastes to these oils. [less ▲]

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See detailObjective assessment of visual pursuit in patients with disorders of consciousness: an exploratory study.
Wannez, Sarah ULg; Hoyoux, Thomas; Langohr, Thomas et al

in Journal of Neurology (2017)

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See detailDiet effects on bumblebee health
Roger, N.; Michez, D.; Wattiez, R. et al

in Journal of Insect Physiology (2017), 96

Among physiological processes, the maintenance of immunity is one of the most energetically costly in invertebrates. Disease resistance can be quantified by measuring immunocompetence, which is defined as ... [more ▼]

Among physiological processes, the maintenance of immunity is one of the most energetically costly in invertebrates. Disease resistance can be quantified by measuring immunocompetence, which is defined as the ability of an organism to mount an immune response, either in cellular, humoral or behavioural forms. In insects, immune capacity can be affected by a variety of factors including pesticides, genetic diversity or diet. Here we focus on an important species of domesticated pollinator, Bombus terrestris, and the potential impact of a poor pollen diet (low nutritional content and toxic) on its health. We investigate three responses at both colony and individual levels: behavioural, humoral and cellular. Our results show that poor pollen diets decrease larval and pupal masses and increase larval ejection as well as adult constitutive immunity (i.e., prophenoloxidase assays). The susceptibility of bumblebees to disease and infection might therefore be greater after a nutritive stress. These findings raise the importance of available plant hosts, especially floral plant species providing pollen with suitable nutritive quality (i.e., nutrient pollen content) for bumblebees. © 2016 Elsevier Ltd [less ▲]

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See detailL’ambiguïté de la médiation. Le cas de la médiation scolaire
Dethier, Baptiste ULg; Dubois, Christophe ULg

in Centre Culturel Omar Khayam (Ed.) La médiation : littéralement et dans tous les sens (2017)

Parmi les études de sciences sociales ayant pris pour objet les pratiques de médiation dans différents champs, citons notamment les contributions récentes d’Élisabeth Volckrick (2015) sur l’enlèvement ... [more ▼]

Parmi les études de sciences sociales ayant pris pour objet les pratiques de médiation dans différents champs, citons notamment les contributions récentes d’Élisabeth Volckrick (2015) sur l’enlèvement parental international d’enfants (voir également sa contribution au présent colloque), de Fabrizio Cantelli (2015) sur la médiation en milieu hospitalier et de Christophe Dubois (2012) sur la justice réparatrice en milieu carcéral. Ces auteurs ont en commun d’étudier des pratiques et des dispositifs s’étant développés comme alternatives ou compléments aux modalités juridiques traditionnelles de prise en charge des droits de l’enfant, des droits du patient et du droit pénal notamment. [less ▲]

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See detailLes droits d'enregistrement
Bourgeois, Marc ULg; Douny, Raphaël ULg; Chauvin, N. et al

in Chronique de Droit à l'Usage du Notariat (2017), 65

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See detailNitrous oxide dynamic in sea ice
Kotovitch, Marie ULg; Fripiat, François ULg; Deman, Florian et al

Poster (2017)

Fluctuations in greenhouse gases (GHGs) concentration alter the energetic budget of the climate system. There is high confidence that natural systems related to snow, ice and frozen ground are affected ... [more ▼]

Fluctuations in greenhouse gases (GHGs) concentration alter the energetic budget of the climate system. There is high confidence that natural systems related to snow, ice and frozen ground are affected. Nitrous oxide (N2O) is one of the potent GHG naturally present in the atmosphere, but witch has seen his concentration growing since industrial era. N2O has a lifetime in the atmosphere of 114 years and a global warming potential 300 time higher than that of CO2. Yet, there are still large uncertainties and gaps in the understanding of the cycle of this compound through the ocean and particularly in sea ice. Sources and sinks of N2O are therefore still poorly quantified. The main processes (except the transport processes) involved in the N2O cycle within the aquatic environment are nitrification and denitrification. To date, only one study by Randall et al. 2012 present N2O measurements in sea ice. Randall et al. pointed out that sea ice formation and melt has the potential to generate sea-air or air-sea fluxes of N2O, respectively. Study on ammonium oxidation and anaerobic bacterial cultures shows that N2O production can potentially occur in sea ice. Denitrification can act as a sink or a source of N2O. In strictly anaerobic conditions, N2O is removed by denitrification. However, denitrification can also occur in presence of O2 at trace level concentrations (<0.2 mg L-1), and in these conditions there is a large N2O production. Recent observations of significant nitrification in Antarctic sea ice shed a new light on nitrogen cycle within sea ice. It has been suggested that nitrification supplies up to 70% of nitrate assimilated within Antarctic spring sea ice. Corollary, production of N2O, a by-product of nitrification, can potentially be significant. This was recently confirmed in Antarctic land fast ice in McMurdo Sound, where N2O release to the atmosphere was estimated to 4 µmol.m-2.yr-1. This assessment is probably an underestimate since it only accounts for dissolved N2O while a significant amount of N2O is likely to occur in the gaseous form like N2, O2 and Ar. This poster address the issue related to the production of N2O within sympagic microorganisms. What process is dominant and how much N2O is produced? The determination of the isotopic composition of N2O using cavity enhanced laser absorption spectroscopy technique (Off-axis ICOS) will allow us to determine the origin of these processes. It will be based on the relative isotope abundance values and site preference data in previous studies. [less ▲]

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See detailApprentissage à l'examen clinique articulaire: le genou
Dumont, Virginie ULg; Montrieux, Christian ULg; Vanmeerbeek, Marc ULg

Learning material (2017)

Cette vidéo, à destination de tous les étudiants en médecine, reprend un bref rappel anatomique de l'articulation du genou . Elle se poursuit par une démonstration de l'examen clinique du genou que tout ... [more ▼]

Cette vidéo, à destination de tous les étudiants en médecine, reprend un bref rappel anatomique de l'articulation du genou . Elle se poursuit par une démonstration de l'examen clinique du genou que tout médecin devrait pouvoir pratiquer au minimum. [less ▲]

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See detailApprentissage à l'examen clinique articulaire: l'épaule
Montrieux, Christian ULg; Vanmeerbeek, Marc ULg; Dumont, Virginie ULg

Learning material (2017)

Cette vidéo, à destination de tous les étudiants en médecine, reprend un bref rappel anatomique de l'articulation de l'éapule . Elle se poursuit par une démonstration de l'examen clinique de l'épaule que ... [more ▼]

Cette vidéo, à destination de tous les étudiants en médecine, reprend un bref rappel anatomique de l'articulation de l'éapule . Elle se poursuit par une démonstration de l'examen clinique de l'épaule que tout médecin devrait pouvoir pratiquer, au minimum [less ▲]

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See detailApprentissage à l'examen clinique articulaire: la colonne vertébrale ( 2ème partie: colonne lombo-sacrée)
Vanmeerbeek, Marc ULg; Montrieux, Christian ULg; Dumont, Virginie ULg

Learning material (2017)

Cette vidéo, à destination de tous les étudiants en médecine, reprend la démonstration de l'examen clinique la colonne lombo sacrée que tout médecin devrait pouvoir pratiquer au minimum

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See detailReduced specificity and enhanced subjective experience of future thinking in ageing: The influence of avoidance and emotion-regulation strategies
Jumentier, Sabrina; Barsics, Catherine ULg; Van der Linden, Martial ULg

in Memory (2017)

Future thinking in older adults is characterised by a lack of specificity of imagined events and by an equal or even higher subjective experience, compared to younger adults. We considered whether this ... [more ▼]

Future thinking in older adults is characterised by a lack of specificity of imagined events and by an equal or even higher subjective experience, compared to younger adults. We considered whether this lack of specificity stemmed partly from the avoidance of a somewhat disturbing future and then examined the extent to which certain types of emotion-regulation strategies, namely positive reappraisal and positive refocusing, contributed to the subjective experience of future thinking. Middle-aged and older adults completed an adapted version of the AMT, in which temporal distance and cue word valence were manipulated, thus resulting in future conditions assumed to represent varying degrees of discomfort. Results indicate that distant future and negative cues restricted both the specificity and the subjective experience of future thinking. In addition, the use of avoidance strategies predicted the nature of future thoughts in the context of a supposed uncomfortable future (i.e., a distant future induced by negative cues), although it followed quite different age-related patterns. Together with the findings that positive reappraisal and positive refocusing (to a lesser extent) contributed to the subjective experience of future thinking, this study indicates that how individuals imagine their personal future also relies on affect- and emotion-regulation strategies. [less ▲]

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See detailPerinatal programming of depressive-like behavior by inflammation in adult offspring mice whose mothers were fed polluted eels: Gender selective effects
Soualed, Nidhal; Dridi, Imen; Eppe, Gauthier ULg et al

in Brain, Behavior & Immunity (2017), 63

Several lines of evidence indicate that early-life inflammation may predispose to mental illness, including depression, in later-life. We investigated the impact of perinatal exposure to polluted eels on ... [more ▼]

Several lines of evidence indicate that early-life inflammation may predispose to mental illness, including depression, in later-life. We investigated the impact of perinatal exposure to polluted eels on neonatal, postnatal, and adult brain inflammation, and on the resignation behavior of male and female adult offspring mice. The effects of maternal standard diet (laboratory food) were compared to the same diet enriched with low, intermediate, or highly polluted eels. Brain inflammatory markers including cytokines were assessed in offspring mice on the day of birth (i.e., on the postnatal day–PND 1), upon weaning (PND 21) and at adulthood (PND 100). Plasma myeloperoxidase and corticosterone levels were evaluated at PND 100. Immobility behavior of offspring was assessed in adulthood (i.e., at PNDs 95–100), using the tail suspension and forced swimming tests. Chronic brain inflammation was found in male and female offspring mice compared to controls, as assessed at PNDs 1, 21, and 100. The level of myeloperoxidase was found to be significantly higher in both adult males and females vs. control offspring. However, high corticosterone levels were only found in male offspring mice that were perinatally exposed to eels, suggesting a gender-selective dysregulation of the adult hypothalamicpituitaryadrenal (HPA) axis. Gender-specific differences were also detected in adulthood in regard to offspring resignation behavior. Thus, compared to controls, males, but not females, whose mothers were fed eels during pregnancy and lactation exhibited a depressive-like behavior in adult age in both behavioral models of depression. Depressive symptoms were more pronounced in male mice perinatally exposed to either intermediate or highly polluted eels than those exposed to only lowly polluted eels. Our results indicate that early-life inflammatory insult is a plausible causative factor that induce the depressive phenotype exhibited by male adult offspring mice, most likely through a gender-specific HPA axis enhanced activation. [less ▲]

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See detailAnxiety modulates the relation between attention- deficit / hyperactivity disorder severity and working memory-related brain activity
Meer, Dennis Van Der; Hoekstra, Pieter J.; Rooij, Daan Van et al

in World Journal of Biological Psychiatry (2017), 0(0), --000

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See detailJoint analysis of area and thickness as a replacement for the analysis of cortical volume
Winkler, Anderson ULg; Greve, Douglas N.; Bjuland, Knut J. et al

in bioRxiv (2017)

Cortical surface area is an increasingly popular brain morphology metric that is ontogenetically and phylogenetically distinct from cortical thickness and offers a separate index of neurodevelopment and ... [more ▼]

Cortical surface area is an increasingly popular brain morphology metric that is ontogenetically and phylogenetically distinct from cortical thickness and offers a separate index of neurodevelopment and disease. However, the various existing methods for assessment of cortical surface area from magnetic resonance images have never been systematically compared. We show that the surface area method implemented in FreeSurfer corresponds closely to the exact, but computationally more demanding, mass-conservative (pycnophylactic) method, provided images are smoothed. Thus, the data produced by this method can be interpreted as estimates of cortical surface area, as opposed to areal expansion. In addition, focusing on the joint analysis of thickness and area, we compare an improved, analytic method for measuring cortical volume to a permutation based non-parametric combination (NPC) method. We analyze area, thickness and volume in young adults born preterm with very low birth weight, using both methods and show that NPC analysis is a more sensitive option for studying joint effects on area and thickness, giving equal weight to variation in both of these two morphological features. [less ▲]

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See detailAssessing cultivar resistance to Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae) using a phenotyping method under semi-field conditions
Chavalle, Sandrine ULg; Jacquemin, Guillaume; De Proft, Michel

in Journal of Applied Entomology (2017)

The orange wheat blossom midge, Sitodiplosis mosellana (Géhin), can significantly reduce wheat yield. Growing resistant wheat cultivars is an effective way of managing this pest. The assessment of ... [more ▼]

The orange wheat blossom midge, Sitodiplosis mosellana (Géhin), can significantly reduce wheat yield. Growing resistant wheat cultivars is an effective way of managing this pest. The assessment of cultivar resistance in field trials is difficult because of unequal pressure of S. mosellana caused by differences in cultivar heading dates relative to the flight period of S. mosellana adult females and huge variations of egg laying conditions from 1 day to another. To overcome these hurdles and to expose all cultivars homogeneously to the pest, an assessment method of cultivar resistance was developed under semi-field conditions. In 2015, the resistance of 64 winter wheat cultivars to S. mosellana was assessed. Few or no larvae developed in the ears of resistant cultivars, but in susceptible cultivars, large numbers of larvae developed. Seventeen cultivars proved to be resistant, whereas 47 were susceptible. The identification of new resistant cultivars offers more opportunities to manage S. mosellana. The phenotyping method is easy, cheap, efficient and reliable. It can be used to guide the breeding of new resistant wheat cultivars. Using specific midge populations, this method could also be used in research on new resistance mechanisms in winter wheat or in other cereal species. [less ▲]

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See detailRigid catheters reduced duration of less invasive surfactant therapy procedures in manikins.
RIGO, Vincent ULg; Debauche, Christian; Maton, Pierre et al

in Acta Paediatrica (2017)

Aim: Different catheters can be used for less invasive surfactant therapy (LIST): feeding tubes inserted with or without Magill forceps, different angiocatheters and centre specific devices, such as ... [more ▼]

Aim: Different catheters can be used for less invasive surfactant therapy (LIST): feeding tubes inserted with or without Magill forceps, different angiocatheters and centre specific devices, such as umbilical catheters affixed to a stylet. This study compared the effectiveness of LIST devices and endotracheal tubes (ETT). Methods: Video recordings of 20 neonatologists simulating different LIST techniques on two manikin heads were analysed. Procedural effectiveness was evaluated by the duration of procedures and failure rates. Ease of use was scored. Results: The median procedure time for the Neonatal Intubation Trainer was significantly longer with feeding tubes without Maggil forceps. For the more difficult ALS Baby Trainer, successful procedures lasted a median of 24 (17-32) seconds with ETT, 24 (15-36) seconds with stylet-guided catheters and 34 (27-46) seconds and 37 (29-42) seconds with 13cm and 30cm angiocatheters, respectively. Both methods using feeding tubes were statistically slower than ETT intubation, lasting 32 (25-44) seconds and 39 (27-95) seconds with or without Maggil forceps. Failure rates (7-20%) were no different between the LIST methods. Techniques using feeding tubes were rated as more difficult. Conclusion: Only rigid or stylet-guided catheters required tracheal catheterisation times similar to those of endotracheal intubation and neonatologists found them easier.  KEY NOTES • This manikin study used video recordings of 20 neonatologists to compare the effectiveness of devices for less invasive surfactant therapy (LIST) and endotracheal tubes. • The durations of tracheal catheterisation for LIST using rigid or stylet-guided catheters were no different from those obtained with endotracheal tubes, but feeding tubes with or without Maggil forceps required longer procedures. • Neonatologists found rigid or stylet-guided catheters easier to use. [less ▲]

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See detailEUFOREA Rhinology Research Forum 2016: report of the brainstorming sessions on needs and priorities in rhinitis and rhinosinusitis.
Hellings, P. W.; Akdis, C. A.; Bachert, C. et al

in Rhinology (2017)

The first European Rhinology Research Forum organized by the European Forum for Research and Education in Allergy and Airway Diseases (EUFOREA) was held in the Royal Academy of Medicine in Brussels on ... [more ▼]

The first European Rhinology Research Forum organized by the European Forum for Research and Education in Allergy and Airway Diseases (EUFOREA) was held in the Royal Academy of Medicine in Brussels on 17th and 18th November 2016, in collaboration with the European Rhinologic Society (ERS) and the Global Allergy and Asthma European Network (GA2LEN). One hundred and thirty participants (medical doctors from different specialties, researchers, as well as patients and industry representatives) from 27 countries took part in the multiple perspective discussions including brainstorming sessions on care pathways and research needs in rhinitis and rhinosinusitis. The debates started with an overview of the current state of the art, including weaknesses and strengths of the current practices, followed by the identification of essential research needs, thoroughly integrated in the context of Precision Medicine (PM), with personalized care, prediction of success of treatment, participation of the patient and prevention of disease as key principles for improving current clinical practices. This report provides a concise summary of the outcomes of the brainstorming sessions of the European Rhinology Research Forum 2016. [less ▲]

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See detailGestion des données et de la connaissance au sein du renseignement
Leroy, Patrick ULg

Learning material (2017)

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