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See detailExploring sex differences in the adult zebra finch brain: in vivo diffusion tensor imaging and ex vivo super-resolution track density imaging
Hamaide, J.; De Groof, G.; Van Steenkiste, G. et al

in NeuroImage (in press)

Zebra finches are an excellent model to study the process of vocal learning, a complex socially-learned tool of communication that forms the basis of spoken human language. So far, structural ... [more ▼]

Zebra finches are an excellent model to study the process of vocal learning, a complex socially-learned tool of communication that forms the basis of spoken human language. So far, structural investigation of the zebra finch brain has been performed ex vivo using invasive methods such as histology. These methods are highly specific, however, they strongly interfere with performing whole-brain analyses and exclude longitudinal studies aimed at establishing causal correlations between neuroplastic events and specific behavioral performances. Therefore, the aim of the current study was to implement an in vivo Diffusion Tensor Imaging (DTI) protocol sensitive enough to detect structural sex differences in the adult zebra finch brain. Voxel-wise comparison of male and female DTI parameter maps shows clear differences in several components of the song control system (i.e. Area X surroundings, the high vocal center (HVC) and the lateral magnocellular nucleus of the anterior nidopallium (LMAN)), which corroborate previous findings and are in line with the clear behavioral difference as only males sing. Furthermore, to obtain additional insights into the 3-dimensional organization of the zebra finch brain and clarify findings obtained by the in vivo study, ex vivo DTI data of the male and female brain were acquired as well, using a recently established super-resolution reconstruction (SRR) imaging strategy. Interestingly, the SRR-DTI approach led to a marked reduction in acquisition time without interfering with the (spatial and angular) resolution and SNR which enabled to acquire a data set characterized by a 78μm isotropic resolution including 90 diffusion gradient directions within 44h of scanning time. Based on the reconstructed SRR-DTI maps, whole brain probabilistic Track Density Imaging (TDI) was performed for the purpose of super resolved track density imaging, further pushing the resolution up to 40μm isotropic. The DTI and TDI maps realized atlas-quality anatomical maps that enable a clear delineation of most components of the song control and auditory systems. In conclusion, this study paves the way for longitudinal in vivo and high-resolution ex vivo experiments aimed at disentangling [less ▲]

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See detailInterest of creatine supplementation insoccer
Miny, Kevin ULg; Burrowes, J; Jidovtseff, Boris ULg

in Science & Sports (in press)

Objectives This review article aimed to summarize the current state of understanding on creatine supplementation for soccer players. In other words, it investigated the beneficial (and potentially ... [more ▼]

Objectives This review article aimed to summarize the current state of understanding on creatine supplementation for soccer players. In other words, it investigated the beneficial (and potentially negative) effects of this supplementation on sport-specific skills and performance in soccer players. Furthermore, this article accordingly discussed the safest and most recommended protocols for the consumption of creatine by these athletes. News Studies have shown that creatine supplementation can have positive effects on sprint and vertical jump performances in soccer players. This supplementation may also enhance soccer players’ muscle strength and adaptation to a high-intensity training regimen. Besides, creatine may be able to enhance muscle glycogen (as well as phosphocreatine) storage, reduce oxidative stress, and improve muscular repair and hypertrophy. Interestingly, creatine supplementation does not seem to affect aerobic performance. Prospects and projects Soccer players could take creatine during pre-season training (3 to 5g/day) in order to help them endure a high-intensity training regimen and enhance their muscular strength and adaptation resulting from strength and/or resistance training. A lower dosage (less than 3g/day) might also be sufficient and beneficial during the season in case of fatigue, in order to sustain adequate levels of phosphocreatine and glycogen in the muscles. Occasional intakes (about 3g) before games and/or extenuating practices could also give a physical and mental boost to the players. Conclusion Most of the studies measured the effects of creatine on skills or physical performances in isolation from the true athletic demands of soccer match play. In conclusion, there is still a need for more research in order to determine whether creatine supplementation is ergogenic regarding the (aerobic) capacity to repeat (very) high-intensity actions, more particularly during competitive soccer. [less ▲]

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See detailOf Pins and Beads: Note on a Feminine Costume in Mari
Couturaud, Barbara ULg

in Ash-Sharq (in press), 1

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See detailVLT/SPHERE robust astrometry of the HR8799 planets at milliarcsecond-level accuracy. Orbital architecture analysis with PyAstrOFit
Wertz, Olivier; Absil, Olivier ULg; Gómez González, Carlos ULg et al

in Astronomy and Astrophysics (in press)

HR8799 is orbited by at least four giant planets, making it a prime target for the recently commissioned Spectro-Polarimetric High-contrast Exoplanet REsearch (VLT/SPHERE). As such, it was observed on ... [more ▼]

HR8799 is orbited by at least four giant planets, making it a prime target for the recently commissioned Spectro-Polarimetric High-contrast Exoplanet REsearch (VLT/SPHERE). As such, it was observed on five consecutive nights during the SPHERE science verification in December 2014. We aim to take full advantage of the SPHERE capabilities to derive accurate astrometric measurements based on H-band images acquired with the Infra-Red Dual-band Imaging and Spectroscopy (IRDIS) subsystem, and to explore the ultimate astrometric performance of SPHERE in this observing mode. We also aim to present a detailed analysis of the orbital parameters for the four planets. We report the astrometric positions for epoch 2014.93 with an accuracy down to 2.0 mas, mainly limited by the astrometric calibration of IRDIS. For each planet, we derive the posterior probability density functions for the six Keplerian elements and identify sets of highly probable orbits. For planet d, there is clear evidence for nonzero eccentricity ($e \simeq 0.35$), without completely excluding solutions with smaller eccentricities. The three other planets are consistent with circular orbits, although their probability distributions spread beyond $e = 0.2$, and show a peak at $e \simeq 0.1$ for planet e. The four planets have consistent inclinations of about $30\deg$ with respect to the sky plane, but the confidence intervals for the longitude of ascending node are disjoint for planets b and c, and we find tentative evidence for non-coplanarity between planets b and c at the $2 \sigma$ level. [less ▲]

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See detailDo flower mixtures with high functional diversity enhance aphid predators in wildflower strips?
Hatt, Séverin ULg; Uyttenbroeck, Roel ULg; Chevalier Mendes Lopes, Thomas ULg et al

in European Journal of Entomology (in press)

Among semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields represent potential habitats for the natural enemies of insect pests. As insects are ... [more ▼]

Among semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields represent potential habitats for the natural enemies of insect pests. As insects are sensitive to a variety of flower traits, we hypothesised that mixtures with high functional diversity attract and support a higher abundance and species richness of aphid flower visiting predators compared to mixtures with low functional diversity. During a field experiment, repeated over two years (2014 and 2015) in Gembloux (Belgium), aphid predators (i.e., lacewings, ladybeetles and hoverflies) were pan-trapped in five sown flower mixtures (including a control mixture, with three replicates of each mixture) of low to high functional diversity based on seven traits (i.e., flower colour, ultra-violet reflectance and pattern, blooming start and duration, height and flower class, primarily based on corolla morphology). In both years, flower species in the sown mixtures (i.e., sown and spontaneous flowers) were listed, and the realised functional diversity of each plot was calculated. Over the two years, an increase in functional diversity did not result in an increase in the abundance and richness of aphid predators. Moreover, ladybeetles, representing the majority of trapped predators, were more abundant in mixtures with very low or intermediary functional diversity at sowing, especially in 2014. We hypothesise that certain flower species, which were abundant in certain mixtures (and not in those exhibiting the highest functional diversity), attracted predators and were sufficiently represented to support them. Our results present novel information that could be used to the development of flower mixtures that provide effective ecosystem services, such as pest control. [less ▲]

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See detailPerineuronal nets and vocal plasticity in songbirds: a proposed mechanism to explain the difference between closed-ended and open-ended learning
Cornez, Gilles ULg; Madison, F.N.; Van der Linden, A. et al

in Developmental Neurobiology (in press)

Perineuronal nets (PNN) are aggregations of chondroitin sulfate proteoglycans surrounding the soma and proximal processes of neurons, mostly GABAergic interneurons expressing parvalbumin. They limit the ... [more ▼]

Perineuronal nets (PNN) are aggregations of chondroitin sulfate proteoglycans surrounding the soma and proximal processes of neurons, mostly GABAergic interneurons expressing parvalbumin. They limit the plasticity of their afferent synaptic connections. In zebra finches PNN develop in an experience-dependent manner in the song control nuclei HVC and RA (nucleus robustus arcopallialis) when young birds crystallize their song. Because songbird species that are open-ended learners tend to recapitulate each year the different phases of song learning until their song crystallizes at the beginning of the breeding season, we tested whether seasonal changes in PNN expression would be found in the song control nuclei of a seasonally breeding species such as the European starling. Only minimal changes in PNN densities and total number of cells surrounded by PNN were detected. However, comparison of the density of PNN and of PNN surrounding parvalbumin-positive cells revealed that these structures are far less numerous in starlings that show extensive adult vocal plasticity, including learning of new songs throughout the year, than in the closed-ended learner zebra finches. Canaries that also display some vocal plasticity across season but were never formally shown to learn new songs in adulthood were intermediate in this respect. Together these data suggest that establishment of PNN around parvalbumin-positive neurons in song control nuclei has diverged during evolution to control the different learning capacities observed in songbird species. This differential expression of PNN in different songbird species could represent a key cellular mechanism mediating species variation between closed-ended and open-ended learning strategies. [less ▲]

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See detailMultiple markers of HVC neurogenesis in the canary
Shevchouk, Olesya ULg; Ball, G.F.; Cornil, Charlotte ULg et al

in PLoS ONE (in press)

In songbirds, neurogenesis in the song control nucleus HVC is sensitive to the hormonal and social environment but the dynamics of this process is difficult to assess with a single exogenous marker of new ... [more ▼]

In songbirds, neurogenesis in the song control nucleus HVC is sensitive to the hormonal and social environment but the dynamics of this process is difficult to assess with a single exogenous marker of new neurons. We simultaneously used three independent markers to investigate HVC neurogenesis in male and female canaries. Males were castrated, implanted with testosterone and housed either alone (M), with a female (M-F) or with another male (M-M) while females were implanted with 17β- estradiol and housed with a male (F-M). All subjects received injections of the two thymidine analogues, BrdU and of EdU, respectively 21 and 10 days before brain collection. Cells containing BrdU or EdU or expressing doublecortin (DCX), which labels newborn neurons, were quantified. Social context and sex differentially affected total BrdU+, EdU+, BrdU+EdU- and DCX+ populations. M-M males had a higher density of BrdU+ cells in the ventricular zone adjacent to HVC and of EdU+ in HVC than M-F males. M birds had a higher ratio of BrdU+EdU- to EdU+ cells than M-F subjects suggesting higher survival of newer neurons in the former group. Total number of HVC DCX+ cells was lower in M-F than in M-M males. Sex differences were also dependent of the type of marker used. Several technical limitations associated with the use of these multiple markers were also identified. These results indicate that proliferation, recruitment and survival of new neurons can be independently affected by environmental conditions and effects can only be fully discerned through the use of multiple neurogenesis markers. [less ▲]

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See detailInlays
Dolce, Rita; Couturaud, Barbara ULg

in Lebeau, M. (Ed.) Associated Regional Chronologies for the Ancient Near East and the Eastern Mediterranean (in press)

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See detailDescription of patients consulting the voice clinic regarding gender, age, occupational status, and diagnosis
Remacle, Angélique ULg; Petitfils, Cloé; FINCK, Camille ULg et al

in European Archives of Oto-rhino-laryngology : Official Journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) (in press)

Purpose. To describe the gender, age, occupational status and diagnosis of dysphonic patients. Method. We retrospectively analyzed the medical records of 1079 patients examined at the Voice clinic of the ... [more ▼]

Purpose. To describe the gender, age, occupational status and diagnosis of dysphonic patients. Method. We retrospectively analyzed the medical records of 1079 patients examined at the Voice clinic of the University hospital of Liège in French-speaking Belgium. Results. Overall, seven out of 10 patients who attended the voice clinic for dysphonia were females. The patients’ ages ranged from 4 to 93 (mean=43.5). Females predominantly consulted at the age of 54 and males at the age of 9. Regarding the occupational status, workers represented more than half of our patients (53%), while 11.2% were unemployed, 15.4% were students, and 19.9% were retired. Regarding the diagnoses of the 1079 patients, nodules were the most common pathologies (n=182, 16.9% of the patients), prevailing in females (n=142, 18.8% of the females), encountered in 16.8% of the workers and 42.8% of the students consulting the voice clinic. Following nodules, laryngeal mobility disorders were diagnosed in 16.4% of the patients (n=177), mainly females (n=115), and was the most frequent diagnosis in retirees (n=75, 34.9%). Conclusions. The majority of the patients consulting the voice clinic for dysphonia were adult females, in their workforce, diagnosed with vocal nodules. The identification of the patients’ characteristics and diagnoses is important to develop treatments and prevention of dysphonia, estimate their costs, and allow comparisons across referral centers. [less ▲]

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See detailThe theoretical instability strip of V777 Her white dwarfs
Van Grootel, Valérie ULg; Fontaine, Gilles; Brassard, Pierre et al

in Astronomical Society of the Pacific Conference Series (in press)

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See detailCoordinated Supervisory Control of Multi-Terminal HVDC Grids: a Model Predictive Control Approach
Papangelis, Lampros ULg; Debry, Marie-Sophie; Panciatici, Patrick et al

in IEEE Transactions on Power Systems (in press)

A coordinated supervisory control scheme for future multi-terminal High-Voltage Direct-Current (HVDC) grids is proposed. The purpose is to supervise the grid and take appropriate actions to ensure power ... [more ▼]

A coordinated supervisory control scheme for future multi-terminal High-Voltage Direct-Current (HVDC) grids is proposed. The purpose is to supervise the grid and take appropriate actions to ensure power balance and prevent or remove voltage or current limit violations. First, using DC current and voltage measurements, the power references of the various Voltage Sources Converters (VSC) are updated according to participation factors. Next, the setpoints of the converters are smoothly adjusted to track those power references, while avoiding or correcting limit violations. The latter function resorts to Model Predictive Control and a sensitivity model of the system. The efficiency of the proposed scheme has been tested through dynamic simulations of a five-terminal HVDC grid interconnecting two asynchronous AC areas and a wind farm. [less ▲]

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See detailCarte géologique de Wallonie. Louveigné-Spa n°49/3-4
Mottequin, Bernard; Geukens, Fernand; Lamberty, Pauline ULg et al

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous editions, in 1898 (at the scale of 1/40.000, by ... [more ▼]

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous editions, in 1898 (at the scale of 1/40.000, by Gustave Dewalque) and the second one, in 1958 (at the scale of 1/25.000 by Paul Fourmarier). [less ▲]

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See detailThe Sense of Taste in Eighteenth-Century France. Flavours of Silence and Words of Perception
Von Hoffmann, Viktoria ULg

in De achttiende eeuw : Documentatieblad van de Werkgroep Achttiende Eeuw (in press), 48(1-2), 13-27

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See detailHarzé - La Gleize. Carte géologique de la Wallonie. Notice explicative
Lamberty, Pauline ULg; Marion, Jean-Marc ULg; Mottequin, Bernard et al

Book published by SPW/Editions (in press)

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced, since the first edition published in 1899 (Gustave Dewalque) at ... [more ▼]

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced, since the first edition published in 1899 (Gustave Dewalque) at the scale of 1/40.000 by the "Commission Géologique de Belgique" and the second one, published in 1959 (Asselberghs & Geukens) at the scale of 1/40.000 by the Geological Survey of Belgium. [less ▲]

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See detailMacroevolutionary analysis of the tempo of diversification in snappers and fusiliers (Percomorpha: Lutjanidae)
Frederich, Bruno ULg; Santini, Francesco

in Belgian Journal of Zoology (in press)

The percomorph fish family Lutjanidae (snappers and fusiliers) includes about 135 reef-dwelling species, mainly confined to tropical and subtropical marine waters. The great majority of snappers are ... [more ▼]

The percomorph fish family Lutjanidae (snappers and fusiliers) includes about 135 reef-dwelling species, mainly confined to tropical and subtropical marine waters. The great majority of snappers are active predators feeding on fishes or crustaceans, even though some species, including the fusiliers (Caesioninae), have evolved zooplanktivory. Lutjanids show a great diversity of habitat preferences, based on depth segregation and distribution across reef and associated habitats (e.g. mangroves, seagrass beds, estuaries). In spite of their great ecological and economic importance little is known about the tempo of evolution in this group. The present study provides the most comprehensive molecular phylogeny to date for lutjanids, including 70% of extant species and 19 of the 21 currently described genera. We time-calibrated our molecular tree using the oldest described lutjanid fossils, and show how this group likely originated during the Late Cretaceous to Early Paleocene. Lutjanids experienced significant radiation during the Late Eocene and Early Oligocene, in contrast to a pattern of Late Oligocene/Miocene radiation observed in many other reef-associated groups. The time-tree allows us to investigate the tempo of diversification, and our results suggest a variation in the rate of speciation during the evolution of the major clade formed by “lutjanins and caesionins”. Variation in diet and life history strategies could explain this clade-specific dynamic, even though future phylogenetic comparative studies combining additional ecological and morphological data are needed to test this hypothesis. [less ▲]

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See detailThe constant of recognizability is computable for primitive morphisms
Durand, Fabien; Leroy, Julien ULg

in Journal of Integer Sequences (in press)

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See detailMarty, Husserl, and the (psycho)logical a priori
Seron, Denis ULg

in Fréchette, Guillaume; Taieb, Hamid (Eds.) Meaning and Intentionality in Anton Marty: Debates and Influences (in press)

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See detailElevated carbon dioxide concentration reduces alarm signaling in aphids
Boullis, Antoine ULg; Fassotte, Bérénice ULg; Sarles, Landry ULg et al

in Journal of Chemical Ecology (in press)

Insects often rely on olfaction to communicate with surrounding conspecifics. While the chemical language of insects has been deciphered in recent decades, few studies have assessed how changes in ... [more ▼]

Insects often rely on olfaction to communicate with surrounding conspecifics. While the chemical language of insects has been deciphered in recent decades, few studies have assessed how changes in atmospheric greenhouse gas concentrations will impact pheromonal communication by insects. Here, we hypothesize that changes in the concentration of atmospheric carbon dioxide (CO2) affect the whole dynamics of alarm signaling in aphids, including: (1) the production of the active compound (E)-β-farnesene (Eβf), (2) emission behavior when under attack, (3) perception by the olfactory apparatus, and (4) the escape response. We reared two strains of the pea aphid Acyrthosiphon pisum under ambient and elevated CO2 concentrations for several generations. We found that an increase in CO2 concentration reduced the production (i.e., individual content) and emission of Eβf (released under predation events). While no difference in Eβf neuronal perception was observed, we found that an increase in CO2 strongly reduces the escape behavior expressed by an aphid colony following exposure to natural doses of the alarm pheromone. In conclusion, our results confirm that changes to greenhouse gases do impact chemical communication in insects, and could potentially have a cascade effect on interactions with higher trophic levels. [less ▲]

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See detailFrom Ontology to Psychoanalysis. Benussi and Musatti on the Concept of Mental Reality
Boccaccini, Federico ULg

in Meinong Studies / Meinong Studien (2018), 9

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