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See detailMapping Posidonia oceanica meadows through time A story of precision, evaluation and fragmentation
Abadie, Arnaud ULiege; Jousseaume, Matthieu; Lejeune, Pierre et al

Poster (2015, May)

Over the last decades, the interest in mapping Posidonia oceanica beds has increased along with the improvement of the equipment’s precision of data acquisition. In Calvi Bay (Corsica, France) the meadows ... [more ▼]

Over the last decades, the interest in mapping Posidonia oceanica beds has increased along with the improvement of the equipment’s precision of data acquisition. In Calvi Bay (Corsica, France) the meadows cover an area of about 5 km² and are found at a depth ranging from 3 m to 37 m. The availability of three distinct datasets for 1997, 2002 and 2010 allowed to assess changes in the patchiness of the meadows in the bay and to investigate evolution of maps precision through a surface analysis via GIS software. Thus, three maps were elaborated combining aerial photographs and side scan sonar images. The meadows percentage of cover through time was assessed using four bathymetric sections: 0-10 m, 11-20 m, 21-30 m and 31-40 m. Differences in the patchiness of P. oceanica meadows between 1997 and 2010 appear to be moderate (less than 3 %) in the sections 0-10 m and 11-20 m and then greatly increase with depth: 24 % at 21-30 m and 39 % at 31-40 m. This amazing regression seems hardly natural and unlikely given the slight quantity of human activities that can cause damages on the P. oceanica meadows of the Calvi Bay. These results are likely to be mainly due to the improvement of precision and resolution of the aerial photographs (5 m in 1997, 0.8 m in 2002 and 0.5 m in 2010) and sonar images (5 m in 1997, 3 m in 2002 and 0.5 m in 2010). An issue of habitat determination (human vs instrumental) linked with the method adopted for mapping can also cause differences in the percentage of cover. Given the different accuracy among the three maps, the real regression and fragmentation of P. oceanica meadows could be hardly assessed. However, in several areas where the human activities are important, a clear regression or even a disappearance of the meadows has been observed. It is obvious that the last maps are more accurate than the previous ones and, thus, the former can be used for management purpose as well as for study on the patchiness; however, they still keep uncertainty no matter which method is used to create them. [less ▲]

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See detailMapping QTL influencing gastrointestinal nematode burden in Dutch Holstein-Friesian dairy cattle.
Coppieters, Wouter ULiege; Mes, Ted H M; Druet, Tom ULiege et al

in BMC Genomics (2009), 10

BACKGROUND: Parasitic gastroenteritis caused by nematodes is only second to mastitis in terms of health costs to dairy farmers in developed countries. Sustainable control strategies complementing ... [more ▼]

BACKGROUND: Parasitic gastroenteritis caused by nematodes is only second to mastitis in terms of health costs to dairy farmers in developed countries. Sustainable control strategies complementing anthelmintics are desired, including selective breeding for enhanced resistance. RESULTS AND CONCLUSION: To quantify and characterize the genetic contribution to variation in resistance to gastro-intestinal parasites, we measured the heritability of faecal egg and larval counts in the Dutch Holstein-Friesian dairy cattle population. The heritability of faecal egg counts ranged from 7 to 21% and was generally higher than for larval counts. We performed a whole genome scan in 12 paternal half-daughter groups for a total of 768 cows, corresponding to the approximately 10% most and least infected daughters within each family (selective genotyping). Two genome-wide significant QTL were identified in an across-family analysis, respectively on chromosomes 9 and 19, coinciding with previous findings in orthologous chromosomal regions in sheep. We identified six more suggestive QTL by within-family analysis. An additional 73 informative SNPs were genotyped on chromosome 19 and the ensuing high density map used in a variance component approach to simultaneously exploit linkage and linkage disequilibrium in an initial inconclusive attempt to refine the QTL map position. [less ▲]

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See detailMapping QTL influencing muscularity in a Texel x Romanov intercross
Marcq, Fabienne ULiege; Elsen, J.-M.; Marot, V. et al

(2000)

Detailed reference viewed: 13 (0 ULiège)
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See detailMapping quantitative trait loci causing the muscular hypertrophy of Belgian Texel sheep
Marcq, Fabienne ULiege; Elsen, J.-M.; Marot, V. et al

(1999)

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See detailMapping quantitative trait loci controlling milk production by exploiting progeny testing
Georges, Michel ULiege; Nielsen, D.; Mackinnon, M. et al

in Genetics (1995), 139

We have exploited "progeny testing" to map quantitative trait loci (QTL) underlying the genetic variation of milk production in a selected dairy cattle population. A total of 1,518 sires, with progeny ... [more ▼]

We have exploited "progeny testing" to map quantitative trait loci (QTL) underlying the genetic variation of milk production in a selected dairy cattle population. A total of 1,518 sires, with progeny tests based on the milking performances of > 150,000 daughters jointly, was genotyped for 159 autosomal microsatellites bracketing 1645 centimorgan or approximately two thirds of the bovine genome. Using a maximum likelihood multilocus linkage analysis accounting for variance heterogeneity of the phenotypes, we identified five chromosomes giving very strong evidence (LOD score > or = 3) for the presence of a QTL controlling milk production: chromosomes 1, 6, 9, 10 and 20. These findings demonstrate that loci with considerable effects on milk production are still segregating in highly selected populations and pave the way toward marker-assisted selection in dairy cattle breeding. [less ▲]

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See detailMapping shallow soil moisture profiles at the field scale using full-waveform inversion of ground penetrating radar data
Minet, Julien ULiege; Wahyudi, A.; Bogaert, P. et al

in Geoderma (2011), 161

Full-waveform inversions were applied to retrieve surface, two-layered and continuous soil moisture profiles from ground penetrating radar (GPR) data acquired in an 11-ha agricultural field situated in ... [more ▼]

Full-waveform inversions were applied to retrieve surface, two-layered and continuous soil moisture profiles from ground penetrating radar (GPR) data acquired in an 11-ha agricultural field situated in the loess belt area in central Belgium. The radar system consisted of a vector network analyzer combined with an off-ground horn antenna operating in the frequency range 200–2000 MHz. The GPR system was computer controlled and synchronized with a differential GPS for real-time data acquisition. Several inversion strategies were also tested using numerical experiments, which in particular demonstrated the potentiality to reconstruct simplified two-layered configurations from more complex, continuous dielectric profiles as prevalent in the environment. The surface soil moisture map obtained assuming a one-layered model showed a global moisture pattern mainly explained by the topography while local moisture patterns indicated a line effect. Two-layered and profile inversions provided consistent estimates with respect to each other and field observations, showing significant moisture increases with depth. However, some discrepancies were ob- served between the measured and modeled GPR data in the higher frequency ranges, mainly due to surface roughness effects which were not accounted for. The proposed GPR method and inversion strategies showed great promise for high-resolution, real-time mapping of soil moisture at the field scale. [less ▲]

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See detailMapping Soil Organic Carbon stocks and estimating uncertainties at the regional scale following a legacy sampling strategy (Southern Belgium, Wallonia)
Chartin, Caroline; Stevens, Antoine; Goidts, Esther et al

in Geoderma Regional (2017), 9

The quantification and the spatialisation of reliable SOC stocks (Mg C ha− 1) and total stock (Tg C) baselines and associated uncertainties are fundamental to detect the gains or losses in SOC, and to ... [more ▼]

The quantification and the spatialisation of reliable SOC stocks (Mg C ha− 1) and total stock (Tg C) baselines and associated uncertainties are fundamental to detect the gains or losses in SOC, and to locate sensitive areas with low SOC levels. Here, we aim to both quantify and spatialize SOC stocks at regional scale (southern Belgium) based on data from one non-design-based or model-based sampling scheme. To this end, we developed a computation procedure based on Digital Soil Mapping techniques and stochastic simulations (Monte-Carlo) allowing the estimation of multiple (here, 10,000) independent spatialized datasets. The computation of the prediction uncertainty accounts for the errors associated to both the estimations of i) SOC stocks and ii) parameters of the spatial model. Based on these 10,000 individuals, median SOC stocks and 90% prediction intervals were computed for each pixel, as well as total SOC stocks and their 90% prediction intervals for selected sub-areas and for the entire study area. Hence, a Generalised Additive Model (GAM) explaining 69.3% of the SOC stock variance was calibrated and then validated (R2 = 0.64). The model overestimated low SOC stock (below 50 Mg C ha− 1) and underestimated high SOC stock (especially those above 100 Mg C kg− 1). A positive gradient of SOC stock occurred from the northwest to the center of Wallonia with a slight decrease on the southernmost part, correlating to the evolution of precipitation and temperature (along with elevation) and dominant land use. At the catchment scale higher SOC stocks were predicted on valley bottoms, especially for poorly drained soils under grassland. Mean predicted SOC stocks for cropland and grassland in Wallonia were of 26.58 Tg C (SD 1.52) and 43.30 Tg C (2.93), respectively. The procedure developed here allowed to predict realistic spatial patterns of SOC stocks all over agricultural lands of southern Belgium and to produce reliable statistics of total SOC stocks for each of the 20 combinations of land use/agricultural regions of Wallonia. This procedure appears useful to produce soil maps as policy tools in conducting sustainable management at regional and national scales, and to compute statistics which comply with specific requirements of reporting activities. [less ▲]

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See detailMapping stakeholder viewpoints in biodiversity management: an application in Niger using Q methodology
Hamadou, Issa; Moula, Nassim ULiege; Siddo, Seyni et al

in Biodiversity and Conservation (2016), 25(10), 1973-1986

The purpose of this paper is to examine the viewpoints of stakeholders in the management and conservation of farm animal biodiversity in Niger. The research applies Q methodology in order to reveal ... [more ▼]

The purpose of this paper is to examine the viewpoints of stakeholders in the management and conservation of farm animal biodiversity in Niger. The research applies Q methodology in order to reveal consensual and divergent discourses. After the development of the set of items on the topic of biodiversity (Q sample), the statements were sorted by the respondents through a 7-grade scale, from −3 to +3. The analysis of Q-sort data with the qmethod package under the R software highlighted three distinct stakeholder viewpoints on the importance of biodiversity in agriculture and animal husbandry, the balance between progress and preservation and the effectiveness of different methods of conservation. The study shows an apparent consensus on the importance of biodiversity that is obviously a promoted topic in the country. Behind the consensus, different discourses are defined that all appear divided by the same dilemma between conservation and economic development. Understanding the different answers and weight attributed to each of the components of the dilemma will guide awareness-raising campaigns and help to pinpoint divergent interests among stakeholders. [less ▲]

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See detailMapping the dependency of crops on pollinators in Belgium
Jacquemin, Floriane ULiege; Violle, Cyrille; Rasmont, Pierre et al

in One Ecosystem (2017)

Detailed reference viewed: 27 (2 ULiège)
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See detailMapping the diachrony of content words: Ancient Greek and Ancient Egyptian as sources for diachronic semantic maps of lexical items
Georgakopoulos, Athanasios ULiege; Polis, Stéphane ULiege

Conference (2017, July 12)

This paper aims at demonstrating how information on the paths of semantic extensions undergone by content words may be incorporated into semantic maps. For this purpose, particular changes that affected ... [more ▼]

This paper aims at demonstrating how information on the paths of semantic extensions undergone by content words may be incorporated into semantic maps. For this purpose, particular changes that affected the meanings of words in the course of the Ancient Greek and of the Ancient Egyptian language history will be investigated. The semantic map model was initially created in order to describe the polysemic patterns of grammatical morphemes (e.g. Haspelmath, 2003). However, recent studies by François (2008), Perrin (2010), Wälchli and Cysouw (2012), and Georgakopoulos et al. (2016) have drawn attention to the lexical domain, showing that the model can be extended to lexical items. It should be noted that the bulk of research has been adopting a synchronic perspective and the limited research that has added the diachronic dimension, has focused mostly on the grammatical domain (e.g. Narrog, 2010). In this paper, we analyze the diachronic evolution of the polysemy network of lexemes in order to produce ‘dynamicised semantic maps’ (Narrog & van der Auwera, 2011) of lexical items. More specifically, we study concepts from the semantic domains of TIME. The data are extracted from dictio-naries, grammars, and the Perseus digital library (http://www.perseus.tufts.edu/hopper/) for Ancient Greek, and from the Thesaurus Linguae Aegyptiae (http://aaew.bbaw.de/tla/), the Ramses corpus (http://ramses.ulg.ac.be), and etymological dictionaries for Ancient Egyptian. Information on synchronic lexical associations are extracted from CLICS (List et al., 2014), an online database containing tendencies of meaning associations. In CLICS, concepts are represented as nodes in the network and instances of polysemy are visualized as links between the nodes. The diachronic dimension of meaning extension may be added to such a network (Figure 1). On the basis of a diachronic analysis of TIME in Ancient Greek (lexical unit: hṓra), which reveals that the meaning ‘time’ is historically prior to the meaning ‘hour,’ we may add a directed arrow representing directionality of change. However, historical priority is not a sufficient criterion for an arrow to be added. Rather, one should be able to show that meaning extensions have a clear motivation.As such, we suggest identifying the cognitive (e.g. metaphor, metonymy, etc.) and the cultural factors that lie behind the observed evolutions. For example, in the case of the Greek concept TIME, one could establish a metonymic motivation between TIME and HOUR, which arises due to the correlation between the canonical time periods and the time these take to unfold. The present study will provide answers to the question of the directionality of change in two particular languages, namely Ancient Greek and Ancient Egyptian. However, our expectation is that by looking at diachrony in this fashion, significant dimensions of directionality of change with cross-linguistic extensions can be revealed. [less ▲]

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See detailMapping the electron energy in Jupiter’s aurora: Hubble spectral observations
Gérard, Jean-Claude ULiege; Bonfond, Bertrand ULiege; Grodent, Denis ULiege et al

in Journal of Geophysical Research. Space Physics (2014), 119

Far ultraviolet spectral observations have been made with the Hubble Space Telescope in the time-tag mode using the Space Telescope Imaging Spectrograph (STIS) long slit. The telescope was slewed in such ... [more ▼]

Far ultraviolet spectral observations have been made with the Hubble Space Telescope in the time-tag mode using the Space Telescope Imaging Spectrograph (STIS) long slit. The telescope was slewed in such a way that the slit projection scanned from above the polar limb down to midlatitudes, allowing us to build up the first spectral maps of the FUV Jovian aurora. The shorter wavelengths are partly absorbed by the methane layer overlying part of the auroral emission layer. The long-wavelength intensity directly reflects the precipitated energy flux carried by the auroral electrons. Maps of the intensity ratio of the two spectral regions have been obtained by combining spectral emissions in two wavelength ranges. They show that the amount of absorption by methane varies significantly between the different components of the aurora and inside the main emission region. Some of the polar emissions are associated with the hardest precipitation, although the auroral regions of strong electron precipitation do not necessarily coincide with the highest electron energies. Outputs from an electron transport model are used to create maps of the distribution of the characteristic electron energies. Using model atmospheres adapted to auroral conditions, we conclude that electron energies range between a few tens to several hundred keV. Comparisons of derived energies are in general agreement with those calculated from magnetosphere-ionosphere coupling models, with values locally exceeding the standard model predictions. These results will provide useful input for three-dimensional modeling of the distribution of particle heat sources into the high-latitude Jovian upper atmosphere. [less ▲]

Detailed reference viewed: 35 (4 ULiège)
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See detailMapping the error due to image geometric correction ?
Hallot, Eric ULiege; Hallot, Pierre ULiege; Cornet, Yves ULiege

Conference (2011, October 14)

Detailed reference viewed: 63 (13 ULiège)
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See detailMapping the expansion of the Northwest Magdalenian
Miller, Rebecca ULiege

in Quaternary International (2012), 272-273

New paleoclimatic data for the Lateglacial clarify climatic phases during the Lateglacial. Cold climate played a key role in limiting Magdalenian expansion from southwest and central Europe This paper ... [more ▼]

New paleoclimatic data for the Lateglacial clarify climatic phases during the Lateglacial. Cold climate played a key role in limiting Magdalenian expansion from southwest and central Europe This paper presents chronological and geographic data for the different climatic phases to map the expansion of the Magdalenian into northwest Europe. Specifically, it can be seen that initial expansion follows a southwest-northeast trajectory into southern Germany, followed by northern expansion into Belgium, central Germany and the Paris Basin at the end of the Oldest Dryas. During the Bølling and Allerød phases, human occupation intensified in the Paris Basin and contacts and/or territorial exploitation between both the Paris Basin and the Rhineland region with Belgian territory is demonstrated. [less ▲]

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See detailMapping the functional connectome traits of levels of consciousness
Amico, Enrico; Marinazzo, Daniele; Di Perri, Carol ULiege et al

in NeuroImage (2017)

Examining task-free functional connectivity (FC) in the human brain offers insights on how spontaneous integration and segregation of information relate to human cognition, and how this organization may ... [more ▼]

Examining task-free functional connectivity (FC) in the human brain offers insights on how spontaneous integration and segregation of information relate to human cognition, and how this organization may be altered in different conditions, and neurological disorders. This is particularly relevant for patients in disorders of consciousness (DOC) following severe acquired brain damage and coma, one of the most devastating conditions in modern medical care. We present a novel data-driven methodology, connICA, which implements Independent Component Analysis (ICA) for the extraction of robust independent FC patterns (FC-traits) from a set of individual functional connectomes, without imposing any a priori data stratification into groups. We here apply connICA to investigate associations between network-traits derived from task-free FC and cognitive features that define levels of consciousness. Three main independent FC-traits were identified and linked to consciousness-related clinical features. The first one represents the functional configuration of an "awake resting" brain, and is associated to the level of arousal. The second FC-trait reflects the disconnection of the visual and sensory-motor connectivity patterns and relates to the ability of communicating with the external environment. The third FC-trait isolates the connectivity pattern encompassing the fronto-parietal and the default-mode network areas as well as the interaction between left and right hemisphere, which are also associated to the awareness of the self and its surroundings. Each FC-trait represents a distinct functional process with a role in the degradation of conscious states in functional brain networks, shedding further light on the functional subcircuits that get disrupted in severe brain-damage. [less ▲]

Detailed reference viewed: 54 (1 ULiège)
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See detailMapping the impact of research-by-design : paths cleared by architectural experimentation
Joachim, Guillaume ULiege

Conference (2017, April 07)

This paper aims at building a critical reflection on the valuation of design experimentation in architectural research and its impact on knowledge production. These considerations are rooted in the ... [more ▼]

This paper aims at building a critical reflection on the valuation of design experimentation in architectural research and its impact on knowledge production. These considerations are rooted in the observation of a hybrid and prospective research experience led at the University of Liège (Revisiting the apartment building 2015-2016), combining documentary research, field investigation, and a research-by-design international design studio gathering 40 architects and students in architecture. We first position the essay on the issue of harnessing design activity for the benefit of architectural research. Secondly we report on the investigation observed and the distinct knowledge production modalities involved in the project. The particular implication of the act of designing is highlighted, among other steps of the investigation, and we put forward some characteristic features of the research process. We particularly consider the different design techniques, tools and representational processes involved in four distinct architectural experimentations and their impact in the emergence of design strategies or spatial interventions. We finally open a discussion on the questions raised by the valuation of these proposals in the research, and stress the inherent tension between opening new perspectives and redefining the scope of inquiry. [less ▲]

Detailed reference viewed: 2 (0 ULiège)
See detailMapping the interplay of policy paradigms and technology assessment in Flanders and Wallonia (Belgium)
Van Oudheusden, Michiel ULiege; Charlier, Nathan ULiege; Rosskamp, Benedikt ULiege et al

Conference (2013, March 13)

This paper empirically assesses how science, technology, and innovation (STI) policies in the regions of Flanders and Wallonia (Belgium) are affected by, and possibly transformed through, technology ... [more ▼]

This paper empirically assesses how science, technology, and innovation (STI) policies in the regions of Flanders and Wallonia (Belgium) are affected by, and possibly transformed through, technology assessment (TA). Broadly defined, TA encompasses activities and programs that seek to expand and deepen the knowledge base of contemporary knowledge-based economies (KBEs), typically by including new actors (e.g. trade unions), ideas (e.g. science in society), and rationales (e.g. participatory techniques) in STI processes. The paper thus seeks to render concrete how TA ideas and programs unfold with, and potentially steer, new articulations of knowledge, which are imperative to present-day STI processes. Drawing on TA case studies in the two regions, the paper illustrates how TA takes on various shapes and forms, including that of mediating instrument, policy-oriented decision-making tool linked to Parliament, and experimental-deliberative mechanism. It is argued that while these TA forms engender new kinds of knowledge and knowledge production, the extent to which TA discourses and practices are effectively taken up in STI is contingent upon how TA taps into, and aligns itself with, global and regional dynamics. The former comprise the convergence of technology research and innovation around the KBE and the advent of strategic science, with its emphasis on real-world problem solving (relevance) and basic research (excellence); the latter entail constitutional reforms that spurred the regionalization of STI policy in Belgium. Our analysis brings a macro-sociological and political sensitivity to bear on TA. Rather than conceiving of TA as a mere management tool or governance technique, we suggest that TA processes enact, as well as counteract, dominant innovation policies. How TA positions itself or is positioned in relation to these policies, is particularly relevant to consider in view of the Flemish Government’s recent decision to abolish its parliamentary TA institute and the Walloon Government’s intention of erecting one. [less ▲]

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See detailMapping the updating process: common and specific brain activations across different versions of the running span task
Collette, Fabienne ULiege; Van der Linden, Martial ULiege; Laureys, Steven ULiege et al

in Cortex : A Journal Devoted to the Study of the Nervous System & Behavior (2007), 43(1), 146-158

Neuroimaging studies exploring the neural substrates of executive functioning have only rarely investigated whether the non-executive characteristics of the experimental executive tasks could contribute ... [more ▼]

Neuroimaging studies exploring the neural substrates of executive functioning have only rarely investigated whether the non-executive characteristics of the experimental executive tasks could contribute to the observed brain activations. The aim of this study was to determine cerebral activity in three different tasks involving the updating executive function. The experimental updating tasks required subjects to process strings of items (respectively letters, words, and sounds) of unknown lengths, and then to recall or identify a specific number of presented items. Conjunction and functional connectivity analyses demonstrated that the cerebral areas activated by all three experimental tasks are the left frontopolar cortex, bilateral dorsolateral prefrontal and premotor cortex, bilateral intraparietal sulcus, right inferior parietal lobule and cerebellum. Some regions of this network appear to be more specific to each updating task. These results clearly indicate that the neural substrates underlying a specific executive process (in this case, updating) are modulated by the exact requirements of the task (such as the material to process or the kind of response) and the specific cognitive processes associated with updating. [less ▲]

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See detailMapping track density changes in nigrostriatal and extranigral pathways in Parkinson's disease
Ziegler, Erik ULiege; Rouillard, Maud; André, Elodie et al

in NeuroImage (2014), 99

Highlights First whole-brain probabilistic tractography study in Parkinson's disease High quality diffusion-weighted images (120 gradient directions, b = 2500 s/mm2) Voxel-based group analysis comparing ... [more ▼]

Highlights First whole-brain probabilistic tractography study in Parkinson's disease High quality diffusion-weighted images (120 gradient directions, b = 2500 s/mm2) Voxel-based group analysis comparing early-stage patients and controls Abnormal reconstructed track density in the nigrostriatal pathway and brainstem Track density also increased in limbic and cognitive circuits. [less ▲]

Detailed reference viewed: 50 (11 ULiège)