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See detailDoes Belgian Holocene speleothem record solar forcing and cold events?
Allan, Mohammed ULiege; Deliège, Adrien ULiege; Nicolay, Samuel ULiege et al

in Climate of the Past Discussions (2017)

We present a decadal-centennial scale Holocene climate record based on trace elements contents from a 65 cm stalagmite (Père Noël) from Belgian Père Noël cave. Père Noël (PN) stalagmite covers the last 12 ... [more ▼]

We present a decadal-centennial scale Holocene climate record based on trace elements contents from a 65 cm stalagmite (Père Noël) from Belgian Père Noël cave. Père Noël (PN) stalagmite covers the last 12.7 ka according to U/Th dating. High spatial resolution measurements of trace elements (Sr, Ba, Mg and Al) were done by Laser-Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). Trace elements profiles were interpreted as environmental and climate changes in the Han-sur-Lesse region. Power spectrum estimators and continuous wavelet transform were applied on trace elements time series to detect any statistically significant periodicities in the PN stalagmite. Spectral analyses reveal decadal to millennial periodicities (i.e., 68–75, 133–136, 198–209, 291–358, 404–602, 912–1029 and 2365–2670 yr) in the speleothem record. Results were compared to reconstructed sunspot number data to determine whether solar signal is presents in PN speleothem. The occurrence of significant solar periodicities (i.e., cycles of Gleissberg, de Vries, unnamed 500 years, Eddy and Hallstat) supports for an impact of solar forcing on PN speleothem trace elements contents. Moreover, several intervals of significant rapid climate change were detected during the Holocene at 10.3, 9.3–9.5, around 8.2, 6.4–6.2, 4.7–4.5, and around 2.7 ka BP. Those intervals are similar to the cold events evidenced in different natural paleoclimate archivers, suggesting common climate forcing mechanisms related to changes in solar irradiance. [less ▲]

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See detailMesenchymal Stromal Cells Accelerate Epithelial Tight Junction Assembly via the AMP-Activated Protein Kinase Pathway, Independently of Liver Kinase B1
Rowart, Pascal ULiege; ERPICUM, Pauline ULiege; KRZESINSKI, Jean-Marie ULiege et al

in Stem Cells International (2017)

Background. Mesenchymal stromal cells (MSC) are fibroblast-like multipotent cells capable of tissue-repair properties. Given the essentiality of tight junctions (TJ) in epithelial integrity, we ... [more ▼]

Background. Mesenchymal stromal cells (MSC) are fibroblast-like multipotent cells capable of tissue-repair properties. Given the essentiality of tight junctions (TJ) in epithelial integrity, we hypothesized that MSC modulate TJ formation, via the AMP-activated kinase (AMPK) pathway. Liver kinase-β1 (LKB1) and Ca2+-calmodulin-dependent protein kinase kinase (CaMKK) represent the main kinases that activate AMPK. Methods. The in vitro Ca2+ switch from 5 μM to 1.8 mM was performed using epithelial Madin-Darby canine kidney (MDCK) cells cultured alone or cocultured with rat bone marrow-derived MSC or preexposed to MSC-conditioned medium. TJ assembly was measured by assessing ZO-1 relocation to cell-cell contacts. Experiments were conducted using MDCK stably expressing short-hairpin-RNA (shRNA) against LKB1 or luciferase (LUC, as controls). Compound STO-609 (50 μM) was used as CaMKK inhibitor. Results. Following Ca2+ switch, ZO-1 relocation and phosphorylation/activation of AMPK were significantly higher in MDCK/MSC compared to MDCK. No difference in AMPK phosphorylation was observed between LKB1-shRNA and Luc-shRNA MDCK following Ca2+ switch. Conversely, incubation with STO-609 prior to Ca2+ switch prevented AMPK phosphorylation and ZO-1 relocation. MSC-conditioned medium slightly but significantly increased AMPK activation and accelerated TJ-associated distribution of ZO-1 post Ca2+ switch in comparison to regular medium. Conclusions. MSC modulate the assembly of epithelial TJ, via the CaMKK/AMPK pathway independently of LKB1. [less ▲]

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See detailDetermining fine population structure using iterative pruning
Chaichoompu, Kridsadakorn ULiege; Yazew, Fentaw Abegaz; Tongsima, Sissades et al

Poster (2017, July 10)

SNP-based information is used in several existing clustering methods to detect shared genetic ancestry or to identify population substructure (Price et al. 2006, Raj et al. 2016). Here, we present an ... [more ▼]

SNP-based information is used in several existing clustering methods to detect shared genetic ancestry or to identify population substructure (Price et al. 2006, Raj et al. 2016). Here, we present an unsupervised clustering algorithm called the iterative pruning method to capture population structure (IPCAPS). Our method supports ordinal data which can be applied directly to SNP data to identify fine-level population structure and it is built on the iterative pruning Principal Component Analysis (ipPCA) algorithm (Intarapanich et al. 2009). The IPCAPS involves an iterative process using multiple splits based on multivariate Gaussian mixture modeling of principal components and Clustering EM estimation as in Lebret et al. (2015). In each iteration, rough clusters and outliers are also identified using our own method called RubikClust. The fixation index (FST) is known to measure a distance between populations and FST = 0.001 may be said to be genetically distinct among the European populations (Tian et al. 2008, Huckins et al. 2014). To observe fine-level population structure using FST, we examined simulated scenarios of one population, 500-8,000 individuals, 5,000-10,000 independent SNPs in HWE (Balding and Nichols 1995), with 100 replicates for each scenario. The simulated SNPs were encoded as additive coding and there was no missing genotype generated. We introduced negative control by subjecting individuals to be separated into two groups using kmeans. We observed that FST values of divided groups were lower than 0.0008, which can be defined as the minimum FST to detect fine-level population structure. To evaluate the performance of our method, we tested different simulated data sets of 2-3 populations, 250 individuals per population, 10,000 independent SNPs in HWE, and FST=[0.0008,0.005], with 100 replicates for each data set. For real-life data sets, we applied the IPCAPS to Thai (Wangkumhang et al. 2013) and HapMap populations. Our method showed that a population classification accuracy was superior to the ipPCA in simulated scenarios of extremely subtle structure (FST=[0.0009,0.005]). In case of the Thai population, results to detect fine-level structure were obtained as well as in case of the HapMap populations. We are convinced that the IPCAPS has a potential to detect fine-level structure and it will be important in molecular reclassification studies of patients once underlying population structure has been removed. [less ▲]

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See detailIncreased sea ice cover disrupts food web structure in Antarctic coastal benthic ecosystem
Michel, Loïc ULiege; Danis, Bruno; Dubois, Philippe et al

Conference (2017, July 10)

Antarctica currently undergoes strong and contrasted impacts linked to climate change. While the West Antarctic Peninsula is one of the most rapidly warming regions in the world, resulting in sea ice ... [more ▼]

Antarctica currently undergoes strong and contrasted impacts linked to climate change. While the West Antarctic Peninsula is one of the most rapidly warming regions in the world, resulting in sea ice cover decrease, the sea ice cover of East Antarctica unexpectedly tends to increase. Here, we studied shallow (0-20 m) benthic food web structure on the coasts of Petrels Island (Adélie Land, East Antarctica) during an event of unusually high spatial and temporal (two successive austral summers without seasonal break-up) sea ice cover. Using time-tested integrative trophic markers (stable isotope ratios of carbon, nitrogen and sulfur) and state-of-the-art data analysis tools (Bayesian ecological models), we studied the structure of the food web associated to benthic macroinvertebrates communities. In total, 28 taxa spanning most present animal groups (sponges, sea anemones, nemerteans, nematods, sipunculids, sessile and mobile polychaetes, gastropods, bivalves, pycnogonids, crustaceans, sea stars, sea urchins, brittle stars and sea cucumbers) and functional guilds (grazers, deposit feeders, filter feeders, predators, scavengers) were investigated. Our results indicate that the absence of seasonal sea ice breakup deeply influences coastal benthic food webs. We recorded marked differences from literature data, both in terms of horizontal (i.e. primary producers and resources supporting animal populations) and vertical (i.e. trophic level of the studied consumers) structure of the food web. Overall, sympagic algae dominated the diet of many key consumers, and the trophic levels of invertebrates were low, suggesting omnivore consumers relied less on predation and/or scavenging than in normal environmental conditions. Surprisingly, few animals seemed to feed on the extremely abundant benthic biofilm, whose exceptional development was also presumably linked with the peculiar sea ice conditions. Comparison of data obtained in the austral summers of 2013-2014 (first year without seasonal breakup) and 2014-2015 (second year without seasonal breakup) clearly showed that the observed trends were linked to actual temporal changes in invertebrate feeding habits rather than with other potential ecological drivers. Our results provide insights about how Antarctic benthic consumers, which have evolved in an extremely stable environment, might adapt their feeding habits in response to sudden changes in environmental conditions and trophic resource availability. They also show that local and/or global trends of sea ice increase in Antarctica have the potential to cause drastic changes in food web structure and therefore impact benthic communities. This research was funded by the Belgian Federal Science Policy Office (BELSPO) in the framework of the vERSO project (http://www.versoproject.be). [less ▲]

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See detailThermal treatments for tailoring the microstructure and wear behaviour of friction stir processed Aluminium-C fibres composites
Mertens, Anne ULiege; Storti, Marco; Simar, Aude et al

Conference (2017, July 10)

A new and simple method for the production of metal matrix composite by friction stir processing (FSP) sandwiches made from metal sheets (e.g. Mg- or Al-based alloy) intercalated with a reinforcing ... [more ▼]

A new and simple method for the production of metal matrix composite by friction stir processing (FSP) sandwiches made from metal sheets (e.g. Mg- or Al-based alloy) intercalated with a reinforcing material e.g. a carbon fabric has recently been devised by the present authors [A. Mertens et al., Mater. Charact. 107 (2015), 125-133]. This process allowed the production of large-size sound metal matrix composites, but the usage properties (e.g. wear resistance,...) of these composites are not yet optimised. Indeed, the matrix of the composite may be softened after processing as FSP is known to cause dissolution of the precipitates responsible for strengthening Mg- or Al-based alloys [A. Simar et al., Mater. Sci. Eng. A 486 (2008), 85-95]. This work thus aims at investigating the potential of thermal treatments for tailoring the microstructure and wear behaviour of age hardenable aluminium alloy 6005 – C fibres composites. The effect of (solution and) ageing treatments on the microstructure and hardness of FSPed Al-C composites has been investigated using optical and scanning electron microscopy, along with Vickers hardness tests. The wear behaviour of the as-FSPed and of the heat treated specimens has been characterized using a pin-on-disc tribometer. Moreover, reference AA6005 samples without C fibres have been produced and tested under similar conditions. The comparison of the reference and of the composite samples allows a better understanding of the role of the C fibres in controlling the grain size of the Al matrix by influencing recrystallisation during FSP and grain growth during thermal treatments. [less ▲]

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See detailStatistical analysis of areal quantities in the brain through permutation tests
Winkler, Anderson ULiege

Doctoral thesis (2017)

In this thesis we demonstrate that direct measurement and comparison across subjects of the surface area of the cerebral cortex at a fine scale is possible using mass conservative interpolation methods ... [more ▼]

In this thesis we demonstrate that direct measurement and comparison across subjects of the surface area of the cerebral cortex at a fine scale is possible using mass conservative interpolation methods. We present a framework for analyses of the cortical surface area, as well as for any other measurement distributed across the cortex that is areal by nature, including cortical gray matter volume. The method consists of the construction of a mesh representation of the cortex, registration to a common coordinate system and, crucially, interpolation using a pycnophylactic method. Statistical analysis of surface area is done with power-transformed data to address lognormality, and inference is done with permutation methods, which can provide exact control of false positives, making only weak assumptions about the data. We further report on results on approximate permutation methods that are more flexible with respect to the experimental design and nuisance variables, conducting detailed simulations to identify the best method for settings that are typical for imaging scenarios. We present a generic framework for permutation inference for complex general linear models (GLMs) when the errors are exchangeable and/or have a symmetric distribution, and show that, even in the presence of nuisance effects, these permutation inferences are powerful. We also demonstrate how the inference on GLM parameters, originally intended for independent data, can be used in certain special but useful cases in which independence is violated. Finally, we show how permutation methods can be applied to combination analyses such as those that include multiple imaging modalities, multiple data acquisitions of the same modality, or simply multiple hypotheses on the same data. For this, we use synchronised permutations, allowing flexibility to integrate imaging data with different spatial resolutions, surface and/or volume-based representations of the brain, including non-imaging data. For the problem of joint inference, we propose a modification of the Non-Parametric Combination (NPC) methodology, such that instead of a two-phase algorithm and large data storage requirements, the inference can be performed in a single phase, with more reasonable computational demands. We also evaluate various combining methods and identify those that provide the best control over error rate and power across. We show that one of these, the method of Tippett, provides a link between correction for the multiplicity of tests and their combination. [less ▲]

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See detailLes pathologies intestinales chirurgicales chez le cheval: activation neutrophilique, pronostic et complications postopératoires
Salciccia, Alexandra ULiege

Doctoral thesis (2017)

Postoperative complications after colic surgery in horses remain of major concern as they are associated with non-negligible mortality rates. Many of these postoperative complications have an important ... [more ▼]

Postoperative complications after colic surgery in horses remain of major concern as they are associated with non-negligible mortality rates. Many of these postoperative complications have an important inflammatory component involving leukocytes, and particularly neutrophils, which represent the majority of granulocytes. Activated neutrophils produce reactive oxygen species and release inflammatory mediators and oxidative and proteolytic enzymes such as myeloperoxidase and elastase, which in turn will exacerbate pre-existing tissue lesions. This cascade of events will lead to the systemic inflammatory response syndrome. In an effort to improve the understanding of the systemic inflammatory reaction that follows colic surgery in horses, we described the time-trends of blood leukocytes and granulocytes counts and plasma myeloperoxidase and elastase concentrations during the perioperative period. Globally, survivor horses presented curves of blood leukocytes and granulocytes counts evolution lower and curve of evolution of plasma myeloperoxidase concentrations higher than those of non-survivor horses. These findings confirm the major influence of the inflammatory reaction on patient survival and allowed us to determine a prognostic value of blood leukocytes counts, a parameter easily available and routinely used in the aftercare of horses undergoing a colic surgery. We showed that in our population, non-survivor horses were more likely to have at least one blood leukocyte count inferior or equal to 3.9×10³/mm³ between 28 and 60 hours after surgery than survivor horses. Our following research, based on clinical studies, were directly or indirectly related to 2 common postoperative complications: incisional complications and ileus. In a study evaluating more than 600 exploratory laparotomies for colic, we showed that short laparotomy incisions, partially closed with interrupted vertical mattress sutures on the linea alba, and protected and supported by an abdominal bandage applied before the recovery from anaesthesia were associated with relatively low incisional complication and infection rates. These rates were respectively 9,52% and 5,31% after a single laparotomy and respectively 33,33% and 26,67% after repeat laparotomy. Bandage related complications occurred rarely. Risk factors of an incisional complication or infection in our population were prolonged anaesthesia duration, performing an enterotomy and postoperative intravenous lidocaine administration. The knowledge of these elements will certainly contribute to reduce the incidence of these complications in the future. Transabdominal ultrasonography of the small intestine is frequently used to diagnose and monitor a postoperative ileus. In order to improve the interpretation of ultrasonographic images after surgery, we determined the influence of general anaesthesia on these images. Using a protocol including horses anaesthetised for non-abdominal surgeries, we showed that although anaesthesia induces a physiologic ileus of short duration, expressed by a decreased of borborygmi without abdominal discomfort, its effects on the ultrasonographic images of the small intestine consisted mainly of a temporary increase (less than 12 hours) of the jejunal visualisation and diameter (with most of the observations remaining in the normal range) without thickening of the intestinal wall. Therefore the effects of general anaesthesia on ultrasonographic images of the small intestine can be distinguished from those of a pathological process. Our last study, including sound horses revealed that lidocaine, a molecule frequently used for treatment of postoperative ileus, may have a mild hypotensive effect on the arterial blood pressure and a mild prokinetic effect on the duodenum. Nevertheless, these results, original about the hypotensive effect, and controverted about the prokinetic effect, need to be confirmed in longer and larger studies. Our work has allowed us to bring some new elements leading to the improvement of our understanding of inflammatory processes related to the neutrophilic activation during the perioperative period of colic horses. Despite the improvement of methods of prevention, detection and treatment of postoperative complications, prognoses after this type of surgery still need to be enhanced. It seems that a huge work remains to be done to precisely determine the effects of various treatments, such as lidocaine. Numerous perspectives appear in the search of new molecules aiming to reduce the inflammatory reaction and to prevent or treat postoperative complications of horses undergoing colic surgery. [less ▲]

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See detailIn vitro antiplasmodial and cytotoxic activities of sesquiterpene lactones from Vernonia fimbrillifera Less. (Asteraceae)
Bordignon, Annélise ULiege; Frederich, Michel ULiege; Ledoux, Allison ULiege et al

in Natural Product Research (2017)

According to the World Health Organization (WHO 2016 WHO. 2016. World Malaria report 2016 [Internet]; [cited 2016 Dec 20]. Available from: https://www.who.int/malaria/publications/world-malaria-report ... [more ▼]

According to the World Health Organization (WHO 2016 WHO. 2016. World Malaria report 2016 [Internet]; [cited 2016 Dec 20]. Available from: https://www.who.int/malaria/publications/world-malaria-report-2016/report/en/ [Google Scholar] ), malaria caused at least 429 000 deaths globally in 2015. Among these, 70% were children under the age of five and 99% were due to the parasite species Plasmodium falciparum. The fight against this major public health problem is threatened by the rapid emergence and spread of parasite strains resistant towards available approved treatments. Urgent efforts are therefore needed to identify new antimalarial drugs. As such, our research groups decided to study Reunion Island as a potential source for the discovery of new antiplasmodial metabolites. This natural patrimony has been identified as a biodiversity hotspot due to its numerous endemic species and its preserved ecosystems (Myers et al. 2000 Myers N, Mittermeier RA, Mittermeier CG, DaFonesca GAB, Kent J. 2000. Biodiversity hotspots for conservation priorities. Nature. 403:853–858.10.1038/35002501 [CrossRef], [PubMed], [Web of Science ®], [Google Scholar] ). The National Botanical Conservatory of the Mascarenes indicates that Vernonia fimbrillifera Less. is an endemic species from Reunion Island, locally named ‘bois de source’, which grows in the humid tropical forest (Lavergne and Véra 1989 Lavergne R, Véra R. 1989. Etude ethnobotanique des plantes utilisées dans la pharmacopée traditionnelle à La Réunion [Ethnobotanical study of plants used in the traditional pharmacopoeia of Reunion Island]. Paris: Agence de coopération culturelle et technique. [Google Scholar] ). To the best of our knowledge, neither phytochemical nor pharmacological works have been performed up to now on V. fimbrillifera. This study isolated and determined the structure of three antiplasmodial sesquiterpene lactones. Compounds were additionally tested in vitro for their cytotoxicity and their selectivity indices were established. [less ▲]

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See detailDépolitisation et politisation de la formation des majorités communales en Belgique
Grandjean, Geoffrey ULiege

Conference (2017, July 10)

Since 2001, the competences for the organization and election of local authorities in Belgium have been regionalized. The Regions – federated powers – are now competent to take law on these matters. The ... [more ▼]

Since 2001, the competences for the organization and election of local authorities in Belgium have been regionalized. The Regions – federated powers – are now competent to take law on these matters. The three Belgian Regions (Brussels-Capital, Flemish and Walloon) have adopted different law which aims to partially depoliticize the naming of mayors and aldermen. The legal rules constrain the political game concerning the composition of the communal colleges and the colleges of mayors and aldermen. The representatives take into account these legal rules during political negotiations for forming a political majority. The dynamics of governance have therefore significantly changed within the municipalities since 2001 and have diverged between the three Regions. In order to illustrate the depoliticization of the naming process of the communal colleges and the colleges of mayors and aldermen and the reappropriation of legal constraints by the representatives, it is proposed to analyze the formation process of political majorities following the last communal elections in the three Regions. For each Region, two municipalities are chosen because of the specificities that arose during the negotiations, leading to the mobilization of multiple arguments (especially legal arguments) to justify the choice of certain coalition partners. This choice makes it possible to highlight the diverse processes of reappropriation of legal constraints by political actors at the local level. [less ▲]

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See detailTrematominae and Artedidraconinae: contrasted mitogenome evolution for two Antarctic radiations
Dettai, Agnes; Auvinet, Juliette; Frederich, Bruno ULiege et al

Conference (2017, July 10)

Cellular respiration has been widely studied in Antarctic teleost fishes because of their peculiar adaptations to an extreme environment. In parallel mitochondrial sequence markers have become highly ... [more ▼]

Cellular respiration has been widely studied in Antarctic teleost fishes because of their peculiar adaptations to an extreme environment. In parallel mitochondrial sequence markers have become highly popular for molecular systematics. However, there are few whole mitochondrial genome sequences published, and none available for some of the subfamilies. Here, we present two large mitogenome datasets including most species and multiple sequences for many species of two subfamilies, Trematominae and Artedidraconinae (Duhamel et al. 2014). These include two highly diverse but very different adaptative radiations, with contrasting divergence dates, morphological polymorphism, and habitat dominance. The sampling is based on a well identified, extensive collection resulting from the 2008 CEAMARC survey and the subsequent REVOLTA surveys in Terre Adélie (IPEV), already DNA barcoded and sequenced in previous studies. The mitogenome sequences for these two subfamilies differ in composition, gene order, and relative divergence of mitochondrial markers, with strong, taxon-specific biases like very high C contents in some regions. The gene order change provides a synapomorphy for the subfamily Trematominae and an interesting development in teleost mitogenomes. The complete Artedidraconinae mitogenomes provide a much higher amount of variable sites (approx*30), while previous sequence datasets were plagued by low informativeness (Lecointre et al. 2011). As already established on single mitochondrial genes, intraspecific variability is lower than interspecific variability within each subfamily, however interspecific variability in Artedidraconinae is lower or similar to intraspecific variability in Trematominae. This expanded dataset confirms the unusual evolution of the mitochondrial coded sequences involved in the cellular respiration in Antarctic Nototheniidae, as well as the usefulness of complete mitochondrial genomes for their systematics. The two level multiplexing (Timmermans et al. 2010) and next generation sequencing of long PCR amplicons (following Hinsinger et al. 2015) is efficient to obtain large mitogenomic datasets representative of both inter- and intraspecific variability, key to the understanding of mitochondrial evolution and a step closer to resolving the relationships among these taxa. [less ▲]

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See detailInfluence of environmental conditions on trophic niche partitioning among sea stars assemblages
Le Bourg, Baptiste ULiege; Blanchard, Alice; Danis, Bruno et al

Conference (2017, July 10)

The Southern Ocean undergoes intense and contrasted impacts linked to climate change. The Western Antarctic Peninsula is one of the most rapidly warming regions of the world (Meredith and King, 2005 ... [more ▼]

The Southern Ocean undergoes intense and contrasted impacts linked to climate change. The Western Antarctic Peninsula is one of the most rapidly warming regions of the world (Meredith and King, 2005), resulting in sharp sea ice cover decrease (Parkinson and Cavalieri, 2012). In contrast, surface temperature and sea ice cover remain stable in other regions such as the Weddell Sea. Sea stars (Echinodermata: Asteroidea) are a key group of the Southern Ocean benthos, thought to be quite resistant to seawater temperature changes (Peck et al., 2008). Other, more indirect environmental changes, might induce important shifts in food web structure and fluxes, that may affect sea stars trophic ecology. In this context, the aim of this study was to use stable isotopes ratios of C, N and S to study sea stars trophic ecology to characterise their trophic diversity and plasticity regarding food web changes. Sea stars were sampled during the austral summer in the South Georgia (sub-Antarctic) in 2011 and in the South Shetland (2006) and South Orkney Islands (2016), as well as in the Weddell Sea (2015-2016). Trophic diversity, i.e. differences of trophic ecology between sea star species, and variability, i.e. differences of trophic ecology between individuals of the same species, were investigated in each region by investigating isotopic dispersion and isotopic niche (proxy of the trophic niche) areas and overlap. Difference in niche width and overlap between the regions may be the result of different environmental conditions, including sea ice coverage and dynamics. For example, in the South Shetland, sea stars had small and poorly differentiated isotopic niches. This result indicate that they may exploit the same benthic communities relying on few common food sources such as organic matter released during sea ice melting (Isla et al., 2006) or sinking phytoplankton (Mincks et al., 2008). Whether this situation leads to competition or not depends on the resources availability. In contrast, isotopic niches were larger and better separated for sea stars from South Georgia. South Georgia is an oligotrophic environment with no sea ice (Korb et al., 2008). As available food items are more limited but, perhaps, more diversified, a higher trophic segregation may appear between species. Ultimately, this project will help delineating processes determining trophic ecology of Southern Ocean sea stars. This research was funded by the Belgian Federal Science Policy Office (BELSPO) in the framework of the vERSO and RECTO project (rectoversoprojects.be). [less ▲]

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See detailDimensions adaptatives des fonctionnements pervers et psychopathiques : une approche étho-phénoménologique
Englebert, Jérôme ULiege

Conference (2017, July 10)

Notre objectif est de discuter des diagnostics du fonctionnement psychologique pervers et de la personnalité psychopathique. Si les versions récentes du DSM (IV et 5) ignorent ces diagnostics, la pratique ... [more ▼]

Notre objectif est de discuter des diagnostics du fonctionnement psychologique pervers et de la personnalité psychopathique. Si les versions récentes du DSM (IV et 5) ignorent ces diagnostics, la pratique clinique suggère de conserver ces deux entités présentant une finesse psychopathologique plus grande et un pouvoir discriminatif plus important que la personnalité antisociale. Nous souhaitons interroger les dimensions intrinsèquement adaptatives de ces deux entités, mais aussi relever leurs différences sur le continuum de l’adaptation. Nous chercherons, en effet, à démontrer que le principe d'adaptation est une dimension centrale et commune aux deux entités, mais qui « se joue » de façons différentes pour chacune. Le pervers est hyper-adapté à son interlocuteur tout en présentant des moments paradoxaux d'inadaptation. Le psychopathe, avec sa faculté de chosification de l'alter ego et ses compétences émotionnelles paradoxales, présente une adaptation plus solitaire. Dans une perspective inspirée des paradigmes éthologique et phénoménologique, nous tenterons de cerner les différences essentielles entre ces deux modes d’être-au-monde. [less ▲]

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See detailNon-destructive investigation of hybrid of ferromagnet /(RE)BCO large grain bulks by flux extraction magnetometry and levitation force
Vanderbemden, Philippe ULiege; Philippe, Matthieu; Wera, Laurent ULiege et al

Conference (2017, July 10)

This work deals with bulk, large grain superconductors used as permanent magnet for rotating machines or levitation applications. It has recently been shown that the magnetic properties of bulk large ... [more ▼]

This work deals with bulk, large grain superconductors used as permanent magnet for rotating machines or levitation applications. It has recently been shown that the magnetic properties of bulk large grain superconductors can be improved easily by attaching a short section of a soft ferromagnetic material (F) to one of the faces of the bulk superconductor (S), thereby producing a hybrid F/S structure [1]. Here we investigate the contactless determination of the magnetic behavior of such structures using a recently constructed bespoke magnetometer based on the flux extraction technique [2]. This device allows magnetic moments as large as 1 Am² to be measured at 77 K and accommodates large bulk samples up to 20 mm diameter. This extends significantly the accessible measurement range of “off-the shelf” magnetometers. Unlike techniques based on recording the distribution of flux at the surface of the sample, the measured signal is representative of the superconducting currents flowing across the entire volume of the sample. In the present work we examine the properties of permanently magnetized superconductors and hybrid structures, and measure the irreversible demagnetization of these structures when they are subjected to magnetic field cycles that are not parallel to their magnetization. We also investigate the levitation behavior of hybrid structures subjected to the non-uniform field of a permanent magnet or a combination of permanent magnets used as guideway for levitation applications, and compare the results to those obtained with a bulk superconductor alone. This abstract is for the special session on bulk superconductivity. References: [1] Egan R. et al., Rev. Sci. Instrum. 86 (2015) 025107 [2] M. P. Philippe et al., Supercond. Sci. Technol. 28 (2015) 095008 Acknowledgments: We greatly acknowledge Nippon Steel & Sumitomo Metal Corporation for providing bulk large grain GdBa2Cu3O7 (GdBCO) samples. [less ▲]

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See detailTraducción y retraducción al francés de Conversación en La Catedral
Belleflamme, Clémence ULiege

Conference (2017, July 09)

La ponencia se inscribe en el marco más amplio de una investigación de doctorado dedicada a la retraducción al francés de obras literarias hispanoamericanas de la segunda mitad del siglo XX. Además de una ... [more ▼]

La ponencia se inscribe en el marco más amplio de una investigación de doctorado dedicada a la retraducción al francés de obras literarias hispanoamericanas de la segunda mitad del siglo XX. Además de una parte teórica, dedicada a la noción traductológica de retraducción, la tesis constará de un estudio de casos, los de Pedro Páramo, de Juan Rulfo, y de Conversación en La Catedral, de Mario Vargas Llosa. Ambas novelas se tradujeron por primera vez al francés unos años después de su publicación y por segunda vez a principios del siglo XXI. Se investigarán tanto las estrategias editoriales como las estrategias de traducción, que un análisis textual de índole descriptivo debería permitirme deducir de manera inductiva a partir de las diferencias lingüísticas y pragmáticas que existen entre las distintas versiones. En esta ponencia, presento los primeros resultados del análisis textual comparativo de las versiones en francés de Conversación en La Catedral y formulo las primeras hipótesis en cuanto a los motivos para retraducir. [less ▲]

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See detailEvaluating flexibility and adequacy in future EU power systems: model coupling and long-term forecasting
Quoilin, Sylvain ULiege; Nijs, Wouter; Zucker, Andreas

in Proceedings of the 2017 ECOS Conference (2017, July 09)

There is an increasing need for improving the representation of the power system in energy system models. Recent research has shown that the economic value of each MWh of Variable Renewable Energy (VRE ... [more ▼]

There is an increasing need for improving the representation of the power system in energy system models. Recent research has shown that the economic value of each MWh of Variable Renewable Energy (VRE) declines with growing deployment. There are two main reasons for this: (1) even with limited shares of VRE, there is a reduced utilisation of dispatchable power plants and (2) with high shares of VRE, there can be possible excess electricity that might have to be curtailed in case of insufficient storage capacity. These findings tend to be completely ignored by models with low temporal resolution and high shares of VRE. In this work, we aim at endogenizing the flexibility constraints into long-term planning models (such as the JRC-EU-TIMES model) by taking profit of Dispa-SET, a unit commitment and optimal dispatch model. The main idea is to derive generic functions from Dispa-SET that can be used by JRC-EU-TIMES and all other energy system models. In particular, we evaluate the impact of increased variable renewable power and different configurations of power systems (production, storage, EVs, demand and flexible demand) (1) on the operations of power plants and the different storage options, determining their economics such as operating hours, number of cycles and (2) on the amount of possible excess power (power that has to be curtailed, stored, or transformed. Simulations are run in Dispa-SET for a wide set of exploratory configurations of the power system in Dispa-SET. Then, a statistical analysis of the results is performed to derive generic flexibility functions. An example of the use of such flexiblity function is finally proposed for a long-term simulation in the JRC-EU-TIMES model at the European level, showing a non-negligible impact on the value of VRE, on the utilization of dispatchable generation, and on the required storage capacity. [less ▲]

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See detailEffects of a giant exercising board game intervention on ambulatory physical activity among nursing home residents: a preliminary study
Mouton, Alexandre ULiege; Gillet, Nicolas; Mouton, Flore et al

Conference (2017, July 08)

Purpose: This study examined the effects of a giant (4 meters by 3 meters) exercising board game intervention on ambulatory physical activity (PA) and on a broader array of physical and psychological ... [more ▼]

Purpose: This study examined the effects of a giant (4 meters by 3 meters) exercising board game intervention on ambulatory physical activity (PA) and on a broader array of physical and psychological outcomes among nursing home residents. Materials and methods: A quasi-experimental longitudinal study was carried out in two comparable nursing homes. Ten participants (aged 82.5 ± 6.3 and comprising 6 women) meeting the inclusion criteria took part to the one-month intervention in one nursing home, whereas eleven participants (aged 89.9 ± 3.1 with 8 women) were assigned to the control group in the other nursing home. The giant exercising board game required participants to perform strength, flexibility, balance and endurance activities. The assistance provided by an exercising specialist decreased gradually during the intervention in an autonomy-oriented approach, based on the self-determination theory (SDT). The following were assessed at baseline, after the intervention and after a follow-up period of three months: PA (steps/day and energy expenditure/day with ActiGraph, GT3X+), cognitive status (MMSE), quality of life (EQ-5D), motivation for PA (BREQ-2), gait and balance (Tinetti and SPPB), functional mobility (Timed Up and Go) and the muscular isometric strength of the lower limb muscles. Results and conclusions: In the intervention group, PA increased from 2921 steps/day at baseline to 3358 steps/day after the intervention (+14.9%, p = 0.04) and 4083 steps/day (+39.8%, p = 0.03) after three months. Energy expenditure/day also increased after the intervention (+110 kcal/day, +6.3%, p = 0.01) and after three months (+219 kcal/day, +12.3%, p = 0.02). Quality of life (p < 0.05), balance and gait (p < 0.05), and strength of the ankle (p < 0.05) were also improved after three months. Such improvements were not observed in the control group. The preliminary results are promising but further investigation is required to confirm and evaluate the longterm effectiveness of PA interventions in nursing homes [less ▲]

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See detailHercules in the Art of Renaissance Flemish Tapestry
Laruelle, Anne-Sophie ULiege

Conference (2017, July 08)

The exploits of Hercules, one of the most popular literary and artistic themes of the Renaissance, flourished particularly in tapestries, a major artistic genre of this period. Fine tapestries presenting ... [more ▼]

The exploits of Hercules, one of the most popular literary and artistic themes of the Renaissance, flourished particularly in tapestries, a major artistic genre of this period. Fine tapestries presenting this theme were produced by the best weaving workshops of the former Netherlands. The success of the theme in tapestry invites us to ponder on the special meaning given to it by the princes, the privileged recipients of these tapestries. There is no doubt that, more than any other hero, Hercules served as their model as he embodied the virtus heroica. We will delve deeper in the matter by focusing on the period between the middle of the fifteenth century (when the theme first appears in tapestries) and the 1560s. In addition to the exceptional quantity of preserved tapestries (over a 100!), the numerous references to the Herculean theme in ancient inventories and descriptions confirms its importance at the time and reveals the complexity of its iconography. [less ▲]

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See detailMémoire et "ouverture" : une analyse de la métaphore (spatiale et chirurgicale) dans Les taupes de Félix Bruzzone
Licata, Nicolas ULiege

Conference (2017, July 08)

À l’inverse d’Aristote, qui l’envisage comme un procédé rhétorique, Nietzsche fait de la métaphore un concept opératoire : une activité instinctive permettant d’accéder à l’essence des choses. Mais ... [more ▼]

À l’inverse d’Aristote, qui l’envisage comme un procédé rhétorique, Nietzsche fait de la métaphore un concept opératoire : une activité instinctive permettant d’accéder à l’essence des choses. Mais l’essence intime des choses, bien qu’indépendante de la métaphore en tant que moyen d’expression, se trouve en elle « comme le père par rapport à son fils », formule le philosophe allemand. Autrement dit, pour autant de fils, c’est-à-dire, de métaphores, que l’on possède, on ne dispose jamais que de dérivés de la chose, pas de la chose elle-même. D’où la nécessité de diversifier les métaphores pour tendre vers une perspective plus ample, plus compréhensive sur la chose. C’est d’ailleurs ce que fait Nietzsche lui-même dans ses essais. C’est aussi, il nous semble, ce que ferait Félix Bruzzone dans le roman ici considéré. Paru en 2008, Les taupes s’inscrit dans la tendance de la literatura de los hijos, ou « littérature des enfants » (sous-entendu, enfants de la dictature). Les caractéristiques qui distinguent ce roman des récits de mémoire traditionnels sont sa discontinuité et son imprévisibilité, ainsi que son langage métaphorique. Errance, voyage, maisons vides et tempêtes, travestisme, chirurgie, le livre contient diverses métaphores, métaphores au sens nietzschéen, large. Certaines d’entre elles sont décodables — on les appelle métaphores in presentia, car on en possède à la fois le « véhicule » et la « teneur » — ; d’autres demeurent absolument indéchiffrables — on nomme celles-là in absentia, car leur « teneur » fait défaut —. Un exemple de métaphore in presentia est le périple qu’effectue le protagoniste vers le sud. Descendre à Bariloche, c’est remonter dans un passé dont on ne peut, semble-t-il, s’extirper. D’un autre côté, on trouve un exemple éclatant de métaphore in absentia dans l’implant mammaire que subit ce même protagoniste dans les dernières pages du roman. Félix Bruzzone nous livre le véhicule de la métaphore mais garde pour lui sa teneur, et entre les deux, les possibilités sont presque infinies. La multiplication des métaphores dans Les taupes et, plus précisément encore, la présence d’une métaphore in absentia, mènent à s’interroger sur le procédé lui-même. Il est surprenant qu’à partir d’un matériau autobiographique Bruzzone produise un récit inachevé et codé. De fait les récits qui prennent pour sujet la dictature adoptent majoritairement la forme réaliste du témoignage. Mais le problème de ces récits est qu’ils reproduisent l’unicité du point de vue dictatorial qu’ils dénoncent. C’est ici que la définition nietzschéenne de la métaphore peut nous illuminer. Bruzzone, en diversifiant les métaphores, propose pour sa part un récit aux multiples points de vue : un roman « ouvert », au sens de collaboration théorique qu’Umberto Eco attribue à ce terme. Et quelle meilleure façon d’éviter le piège d’opposer à la dictature un autre point de vue unique, après tout, que d’inviter le lecteur à s’impliquer mentalement dans la réflexion à son sujet ? [less ▲]

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