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See detailSedimentology and magnetic susceptibility of recent sediments from New Caledonia
Jadot, Hélène ULg; Boulvain, Frédéric ULg

in Special Publication - Geological Society of London (2015), 414

The interpretation of the primary origin of the minerals carrying the magnetic susceptibility (MS) signal from ancient rocks suffers notably from the scarcity of studies on Recent sediments. To bring new ... [more ▼]

The interpretation of the primary origin of the minerals carrying the magnetic susceptibility (MS) signal from ancient rocks suffers notably from the scarcity of studies on Recent sediments. To bring new data, a study of tropical coastal sediments of New Caledonia was undertaken. This island is surrounded by a nearly uninterrupted reef barrier, isolating a wide lagoon from the open ocean. The erosion of extremely varied rocks (from mantle rocks to laterites) produces different types of detrital sediments, which are mixed with the indigenous precipitated carbonates. This generates different types of coastal sediments, detrital- or carbonate-dominated or mixed. More than 300 samples were analysed for grain size, nature of sediment, MS and geochemistry (major elements). The first results show that: (a) carbonate sands and carbonate silts are characterized by lower MS than detrital sediments; (b) the MS signal of mixed sediments is mostly influenced by the proportion of detrital sediments; (c) MS is directly correlated with Mn and Fe content; (d) beachrocks are characterized by lower MS than equivalent loose sediment; (e) the MS signal of carbonate sediments is locally positively correlated with granulometry; (f) there is no MS change between surface and 20 cm deep samples; and (g) when the subsurface sediment is reducing, the MS is higher than that from surface sediment. [less ▲]

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See detailGenome-wide transcriptional analysis suggests hydrogenase- and nitrogenase-mediated hydrogen production in Clostridium butyricum CWBI 1009
Calusinska, Magda; Hamilton, Christopher; Monsieurs, Pieter et al

in Biotechnology for Biofuels (2015), 8(27), 1-16

Background: Molecular hydrogen, given its pollution-free combustion, has great potential to replace fossil fuels in future transportation and energy production. However, current industrial hydrogen ... [more ▼]

Background: Molecular hydrogen, given its pollution-free combustion, has great potential to replace fossil fuels in future transportation and energy production. However, current industrial hydrogen production processes, such as steam reforming of methane, contribute significantly to the greenhouse effect. Therefore alternative methods, in particular the use of fermentative microorganisms, have attracted scientific interest in recent years. However the low overall yield obtained is a major challenge in biological H2 production. Thus, a thorough and detailed understanding of the relationships between genome content, gene expression patterns, pathway utilisation and metabolite synthesis is required to optimise the yield of biohydrogen production pathways. Results: In this study transcriptomic and proteomic analyses of the hydrogen-producing bacterium Clostridium butyricum CWBI 1009 were carried out to provide a biomolecular overview of the changes that occur when the metabolism shifts to H2 production. The growth, H2-production, and glucose-fermentation profiles were monitored in 20 L batch bioreactors under unregulated-pH and fixed-pH conditions (pH 7.3 and 5.2). Conspicuous differences were observed in the bioreactor performances and cellular metabolisms for all the tested metabolites, and they were pH dependent. During unregulated-pH glucose fermentation increased H2 production was associated with concurrent strong up-regulation of the nitrogenase coding genes. However, no such concurrent up-regulation of the [FeFe] hydrogenase genes was observed. During the fixed pH 5.2 fermentation, by contrast, the expression levels for the [FeFe] hydrogenase coding genes were higher than during the unregulated-pH fermentation, while the nitrogenase transcripts were less abundant. The overall results suggest, for the first time, that environmental factors may determine whether H2 production in C. butyricum CWBI 1009 is mediated by the hydrogenases and/or the nitrogenase. Conclusions: This work, contributing to the field of dark fermentative hydrogen production, provides a multidisciplinary approach for the investigation of the processes involved in the molecular H2 metabolism of clostridia. In addition, it lays the groundwork for further optimisation of biohydrogen production pathways based on genetic engineering techniques. [less ▲]

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See detailOleuropein or rutin consumption decreases the spontaneous development of osteoarthritis in the Hartley guinea pig.
Horcajada, M.-N.; Sanchez, Christelle ULg; Membrez Scalfo et al

in Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society (2015), 23(1), 94-102

OBJECTIVE: To assess the potential protective effects of three polyphenols oleuropein, rutin and curcumin, on joint ageing and osteoarthritis (OA) development. DESIGN: Sixty 4-week-old Dunkin-Hartley ... [more ▼]

OBJECTIVE: To assess the potential protective effects of three polyphenols oleuropein, rutin and curcumin, on joint ageing and osteoarthritis (OA) development. DESIGN: Sixty 4-week-old Dunkin-Hartley guinea pigs were randomized into four groups and received daily during 31 weeks either standard guinea pig diet (control group) or a standard guinea pig diet enriched with oleuropein (0.025%), rutin (0.5%) or rutin/curcumin (0.5%/0.25%) association. Biomarkers of OA (Coll2-1, Coll2-1NO2, Fib3-1, Fib3-2, ARGS), as well as inflammation (PGE2) were quantified in the serum. Histological assessments of knee cartilage and synovial membrane were performed at week 4 (five young reference guinea pigs) and week 35. RESULTS: At week 35, guinea pigs in the control group spontaneously developed significant cartilage lesions with mild synovial inflammation. The histological scores of cartilage lesions and synovitis were well correlated with the increased level of serum biomarkers. Histologically, all treatments significantly reduced the cartilage degradation score (P < 0.01), but only oleuropein significantly decreased the synovial histological score (P < 0.05) and serum PGE2 levels (P < 0.01) compared to the control group. Coll2-1 was decreased by rutin and the combination of rutin/curcumin, Fib3-1 and Fib3-2 were only decreased by the rutin/curcumin mixture, while Coll2-1NO2 was significantly decreased by all treatments (P < 0.05). CONCLUSION: Oleuropein and rutin +/- curcumin significantly slowed down the progression of spontaneous OA lesions in guinea pigs. While no additive effect was seen in the curcumin + rutin group, the differential effects of oleuropein and rutin on inflammatory and cartilage catabolic markers suggest an interesting combination for future studies in OA protection. [less ▲]

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See detailClinical inertia in general practice, a matter of debate: a qualitative study with 114 general practitioners in Belgium.
Aujoulat, Isabelle; Jacquemin, Patricia; Hermans, Michel et al

in BMC family practice (2015), 16(1), 13

BackgroundPrescribing that is not concordant with guidelines is increasingly referred to as clinical inertia (CI). However, CI may be only apparent, and the absence of decision may actually reflect ... [more ▼]

BackgroundPrescribing that is not concordant with guidelines is increasingly referred to as clinical inertia (CI). However, CI may be only apparent, and the absence of decision may actually reflect appropriate inaction as a result of good clinical reasoning. Our study aimed to: (i) elucidate GPs inverted question mark beliefs regarding CI and the risk of CI in their own practice, (ii) identify modifiable provider-related factors associated with CI.MethodsWe conducted 8 group interviews with 114 general practitioners (GP) in Belgium, and used an integrated approach of thematic analysis.ResultsOur results call for a redefinition of CI, in order to take into account the GPs inverted question mark extended health-promoting role, and acknowledge that inaction or delayed action follows a process of clinical reasoning that takes into account the patients inverted question mark preferences, and that is appropriate most of the time. However, the participants in our study did acknowledge that the risk of CI exists in practice. The main factor of such a risk is when GPs feel overwhelmed and disempowered, due to characteristics of either the patients or the health care system, including contradictions between guidelines and reimbursement policies.ConclusionsAlthough situations of clinical inertia exist in practice and need to be prevented or corrected, the term clinical inertia could potentially increase the already existing gap between general practice and specialised care, whereas sustained efforts toward more collaborative work and integrated care are called for. [less ▲]

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See detailEducation et formation en médecine gériatrique en Europe : challenge du futur?
ROLLER, REGINA ELISABETH; PETERMANS, Jean ULg

in Gériatrie et Psychologie Neuropsychiatrie du Vieillissement (2015)

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See detailMedical education and training in geriatrics in the 21st centrury. Where do we come from - where do we go ?
Roller, Regina Elisabeth; PETERMANS, Jean ULg

in European Geriatric Medicine (2015)

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See detailGestural expressions of spatial information in L1 and L2
Maarten, Lemmens; Perrez, Julien ULg

Conference (2015)

This paper reports on the analysis of gestures in the expression of static locative relationships in French and Dutch, for L1 speakers as well as for francophone learners of Dutch (L2). The data analysed ... [more ▼]

This paper reports on the analysis of gestures in the expression of static locative relationships in French and Dutch, for L1 speakers as well as for francophone learners of Dutch (L2). The data analysed is drawn from video-taped picture descriptions where subjects were asked to talk about the location of certain entities on these pictures. Tutton (2012) has observed that in spatial descriptions gestures often express information that remains unexpressed in the verbal production and that typically the information that is gesturally expressed is directional (cf. also McNeill 2000; Gullberg 2009, 2010). Our data only partially confirm his findings: in most cases, gestures express information that is also expressed verbally. In addition, while gestures are indeed well-suited to express direction, we argue that a clearer distinction is needed between directional and (purely) locational gestures. We suggest that the crucial factor identifying a locative gesture is the fact of the gesture being anchored in the representational gesture space, an issue that hitherto has not been discussed in the literature. While all gestures are necessarily made in the gesture space, anchored gestures are those that receive a clear representational location. These can be pointing gestures, but often they are not (e.g., an anchored shape-, size- or manner-gesture). Functionally, they are not unlike what Liddell (2003) has called buoys in ASL, i.e., clearly located and stationary signs that function as conceptual landmarks while the discourse continues. The difference with anchored gestures is that the latter are not stationary. Non-anchored gestures do not have such a precise location. For example, directional gestures are not really anchored to a specific point, but merely indicate a direction. Similarly, some iconic gestures express locative relations (e.g. BETWEEN, EVERYWHERE), but are made without being anchored in the representational gesture space (e.g., just in front of the speaker, in centre space). We argue that despite their locative semantics, they are not locative gestures. In fact, anchored locative gestures could thus be seen as grounding predications, i.e. "an instance (but not a type) is thought of as having a particular location in the domain of instantiation" (Langacker 1991:57). In addition, typological differences are manifest in gesture. In line with Talmy’s (2000) typological distinction between verb-framed and satellite-framed languages, Dutch can be described as a “location-rich” language and the descriptions of the native Dutch speakers abound with locative descriptions, through the highly grammaticalised use of posture verbs but also via other linguistic means (prepositions, adverbs, etc.). French, in contrast, is “location-poor”: the French narrations have significantly fewer locative descriptions and the locative information is much more general. Instead, they add narrative detail and meta-linguistic comments to their descriptions. The francophone learners of Dutch (with 3 levels of proficiency) use more gestures revealing the challenge that free expression in a second language poses, especially for the lowest proficiency levels: they use more shape gestures, more enactment gestures (e.g., pulling a drawer, brushing one’s hair, etc.), more reality-anchored gestures (e.g., pointing at one’s shoes when talking about shoes), and more meta-communicative gestures indicating their lexical shortcomings, e.g., word- search gestures (see Ladewig 2011). Overall, and as can be expected, the low proficiency L2 speakers use almost more gestures than words, which can be seen as a visual compensation for their lack of lexical accuracy; the gestural expression of advanced learners, in contrast, is much more locational in nature, in line with the target language (cf. also Gullberg 2009, 2010, Alferink & Gullberg 2014). [less ▲]

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See detailFluid fragmentation shapes rain-induced foliar disease transmission
Gilet, Tristan ULg; Bourouiba, Lydia

in Journal of the Royal Society, Interface (2015), 12

Plant diseases represent a growing threat to the global food supply. The factors contributing to pathogen transmission from plant to plant remain poorly understood. Statistical correlations between ... [more ▼]

Plant diseases represent a growing threat to the global food supply. The factors contributing to pathogen transmission from plant to plant remain poorly understood. Statistical correlations between rainfalls and plant disease out- breaks were reported; however, the detailed mechanisms linking the two were relegated to a black box. In this combined experimental and theoretical study, we focus on the impact dynamics of raindrops on infected leaves, one drop at a time. We find that the deposition range of most of the pathogen-bear- ing droplets is constrained by a hydrodynamical condition and we quantify the effect of leaf size and compliance on such constraint. Moreover, we identify and characterize two dominant fluid fragmentation scenarios as responsible for the dispersal of most pathogen-bearing droplets emitted from infected leaves: (i) the crescent-moon ejection is driven by the direct interaction between the impacting raindrop and the contaminated sessile drop and (ii) the inertial detachment is driven by the motion imparted to the leaf by the raindrop, lead- ing to catapult-like droplet ejections. We find that at first, decreasing leaf size or increasing compliance reduces the range of pathogen-bearing droplets and the subsequent epidemic onset efficiency. However, this conclusion only applies for the crescent moon ejection. Above a certain compliance threshold a more effective mechanism of contaminated fluid ejection, the inertial detachment, emerges. This compliance threshold is determined by the ratio between the leaf velocity and the characteristic velocity of fluid fragmentation. The inertial detachment mechanism enhances the range of deposition of the larger con- taminated droplets and suggests a change in epidemic onset pattern and a more efficient potential of infection of neighbouring plants. Dimensionless parameters and scaling laws are provided to rationalize our observations. Our results link for the first time the mechanical properties of foliage with the onset dynamics of foliar epidemics through the lens of fluid fragmentation. We discuss how the reported findings can inform the design of mitigation strategies acting at the early stage of a foliar disease outbreak. [less ▲]

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See detailDetection of differential item functioning using the lasso approach
Magis, David ULg; Tuerlinckx, Francis; De Boeck, Paul

in Journal of Educational & Behavioral Statistics (2015), 40

This paper proposes a novel approach to detect differential item functioning (DIF) among dichotomously scored items. Unlike standard DIF methods that perform an item-by-item analysis, we propose the “LR ... [more ▼]

This paper proposes a novel approach to detect differential item functioning (DIF) among dichotomously scored items. Unlike standard DIF methods that perform an item-by-item analysis, we propose the “LR lasso DIF method”: logistic regression (LR) model is formulated for all item responses. The model contains item specific intercepts, an effect of the sum score and item-group interaction (i.e. DIF) effects, with a lasso penalty on all DIF parameters. Optimal penalty parameter selection is investigated through several known information criteria (AIC, BIC and cross-validation) as well as through a newly developed alternative. A simulation study was conducted to compare the global performance of the suggested “LR lasso DIF” method to the logistic regression and Mantel-Haenszel methods (in terms of false alarm and hit rates). It is concluded that for small samples the LR lasso DIF approach globally outperforms the logistic regression method, and also the Mantel-Haenszel method, especially in the presence of item impact, while it yields similar results with larger samples. [less ▲]

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See detailJules Mathieu (1937-1943)
Lanneau, Catherine ULg

in Raxhon, Philippe (Ed.) Les Gouverneurs de la Province de Liège. Histoire d’une fonction, mémoire d’une action (2015)

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See detailThe aerodynamic cost of head morphology in bats: maybe not as bad as it seems
Vanderelst, Dieter; Peremans, Herbert; Abdul Razak, Norizham et al

in PLoS ONE (2015), 10(3), 0118545

At first sight, echolocating bats face a difficult trade-off. As flying animals, they would benefit from a streamlined geometric shape to reduce aerodynamic drag and increase flight efficiency. However ... [more ▼]

At first sight, echolocating bats face a difficult trade-off. As flying animals, they would benefit from a streamlined geometric shape to reduce aerodynamic drag and increase flight efficiency. However, as echolocating animals, their pinnae generate the acoustic cues necessary for navigation and foraging. Moreover, species emitting sound through their nostrils often feature elaborate noseleaves that help in focussing the emitted echolocation pulses. Both pinnae and noseleaves reduce the streamlined character of a bat’s morphology. It is generally assumed that by compromising the streamlined charactered of the geometry, the head morphology generates substantial drag, thereby reducing flight efficiency. In contrast, it has also been suggested that the pinnae of bats generate lift forces counteracting the detrimental effect of the increased drag. However, very little data exist on the aerodynamic properties of bat pinnae and noseleaves. In this work, the aerodynamic forces generated by the heads of seven species of bats, including noseleaved bats, are measured by testing detailed 3D models in a wind tunnel. Models of Myotis daubentonii, Macrophyllum macrophyllum, Micronycteris microtis, Eptesicus fuscus, Rhinolophus formosae, Rhinolophus rouxi and Phyllostomus discolor are tested. The results confirm that non-streamlined facial morphologies yield considerable drag forces but also generate substantial lift. The net effect is a slight increase in the lift-to-drag ratio. Therefore, there is no evidence of high aerodynamic costs associated with the morphology of bat heads [less ▲]

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See detailAsteroid polarimetry : validation run on the CAPS polarimeter
Devogele, Maxime ULg; Cellino, A.; Massone, G. et al

Conference (2015)

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See detailGilbert Mottard (1971-1990)
Lanneau, Catherine ULg

in Raxhon, Philippe (Ed.) Les Gouverneurs de la Province de Liège. Histoire d’une fonction, mémoire d’une action (2015)

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See detailJoseph Leclercq (1944-1953)
Lanneau, Catherine ULg

in Raxhon, Philippe (Ed.) Les Gouverneurs de la Province de Liège. Histoire d’une fonction, mémoire d’une action (2015)

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See detailDéveloppement récent de la culture de l'épeautre en Belgique
Burny, Philippe ULg

in Watillon, Bernard; Bodson, Bernard (Eds.) Livre Blanc "Céréales", édition février 2015 (2015)

L'épeautre est une culture ancienne, pratiquée depuis des siècles, et qui a été progressivement remplacée, comme le seigle, par le froment. Il s'est cependant maintenu modestement dans quelques régions ... [more ▼]

L'épeautre est une culture ancienne, pratiquée depuis des siècles, et qui a été progressivement remplacée, comme le seigle, par le froment. Il s'est cependant maintenu modestement dans quelques régions aux sols plus pauvres et au climat plus rigoureux que ceux qui conviennent le mieux au froment. Les aspects "santé" prenant de plus en plus d'importance dans les pays riches, la bonne réputation de l'épeautre en ce domaine a permis un récent regain d'intérêt pour cette culture, dont les prix se sont envolés au cours de l'année 2014. Cette évolution est-elle durable ou ne sera-t-elle qu'un feu de paille ? [less ▲]

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See detailEtudes sartriennes, n° 19 : Jean-Paul Sartre, Morale et Histoire. Conférence à l’institut Gramsci 1964
Bourgault, Jean; Cormann, Grégory ULg

Book published by Ousia (2015)

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See detailThe “Belgian Tetris”: assessing the political impact of metaphors on citizens’ perception of and attitude towards Belgian federalism.
Perrez, Julien ULg; Reuchamps, Min

Conference (2015)

In the literature, the political impact of metaphors has often been taken for granted from metaphor analysis in political discourse. However, a more global understanding of what this political impact ... [more ▼]

In the literature, the political impact of metaphors has often been taken for granted from metaphor analysis in political discourse. However, a more global understanding of what this political impact could consist of, is still lacking from the current research agenda. To be able to account for how metaphors, through discourses, actively shape the political reality, it is important to look at the relationships between metaphorical discourses and their environment. Based on the idea that metaphors do not only reflect the perceived reality, but also function as cues through which citizens come to understand complex political processes (Bougher 2012), the aim of this study is precisely to look at how specific metaphors might impact on the citizens’ framing of Belgian federalism. To measure the impact of metaphors on the citizens’ political representations and attitudes, we conducted a first experiment among 493 citizens based on an article (including a text and an image) published in the newspaper Le Soir (13-14 July 2013) in which Belgian federalism was deliberately compared to a Tetris game (AUTHORS, submitted). The participants were distributed into four experimental conditions according to the type of input they had been exposed to (respectively no input, text and image, image only, text only), and were asked to perform three interrelated tasks (a free description task, a picture association task and a questionnaire measuring their attitude towards Belgian federalism). The productions of the participants in the description task have been analyzed using keyword analyses and content analyses. The results suggest that the participants who had been exposed to the experimental text tend to differently frame their perception of Belgian federalism (among other things, by highlighting the notion of transfer of competences from the federal state to the sub-national entities). Whereas these results suggest that reading the text might have an impact on the representations of the citizens, they do not allow us to pinpoint the specific role played by the Tetris metaphor itself on these different representations. To further determine to what extent the observed influence of the text on the citizens’ representations can be attributed to the Tetris metaphor, we developed a follow-up experiment for which we produced two versions of the experimental text, namely a version in which the Tetris metaphor remained explicit and a version in which it had been left out. We conducted the experiment among 600 citizens distributed into 3 experimental conditions (respectively no input, original text, original text without explicit reference to the Tetris metaphor). They were asked to achieve the same three tasks as in the original experiment. The results are currently being analyzed and will be the main subject of our contribution. This experimental design should allow us (i) to observe the specific influence of the Tetris metaphor on the integration of textual information and (ii) to assess to what extent it shapes the citizens’ representations of Belgian federalism. [less ▲]

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See detailBiogeochemical processes and buffering capacity concurrently affect acidification in a seasonally hypoxic coastal marine basin
Hagens, M.; Slomp, C. P.; Meysman, F. J. R. et al

in Biogeosciences (2015), 12(5), 1561--1583

Coastal areas are impacted by multiple natural and anthropogenic processes and experience stronger pH fluctuations than the open ocean. These variations can weaken or intensify the ocean acidification ... [more ▼]

Coastal areas are impacted by multiple natural and anthropogenic processes and experience stronger pH fluctuations than the open ocean. These variations can weaken or intensify the ocean acidification signal induced by increasing atmospheric pCO2. The development of eutrophication-induced hypoxia intensifies coastal acidification, since the CO2 produced during respiration decreases the buffering capacity in any hypoxic bottom water. To assess the combined ecosystem impacts of acidification and hypoxia, we quantified the seasonal variation in pH and oxygen dynamics in the water column of a seasonally stratified coastal basin (Lake Grevelingen, the Netherlands). Monthly water-column chemistry measurements were complemented with estimates of primary production and respiration using O2 light–dark incubations, in addition to sediment–water fluxes of dissolved inorganic carbon (DIC) and total alkalinity (TA). The resulting data set was used to set up a proton budget on a seasonal scale. Temperature-induced seasonal stratification combined with a high community respiration was responsible for the depletion of oxygen in the bottom water in summer. The surface water showed strong seasonal variation in process rates (primary production, CO2 air–sea exchange), but relatively small seasonal pH fluctuations (0.46 units on the total hydrogen ion scale). In contrast, the bottom water showed less seasonality in biogeochemical rates (respiration, sediment–water exchange), but stronger pH fluctuations (0.60 units). This marked difference in pH dynamics could be attributed to a substantial reduction in the acid–base buffering capacity of the hypoxic bottom water in the summer period. Our results highlight the importance of acid–base buffering in the pH dynamics of coastal systems and illustrate the increasing vulnerability of hypoxic, CO2-rich waters to any acidifying process. [less ▲]

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