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See detailImportance of pigtailed macaques (Macaca nemestrina leonina) in seed dispersal: impact on the ecological balance of the tropical rainforest at Khao Yai National Park, Thailand
Albert, Aurélie ULiege; Huynen, Marie-Claude ULiege; Savini, Tommaso ULiege

Poster (2010)

Today, many countries of South-East Asia know about the alarming state of the forests existing on their territory and all agree that it is essential to save the remaining primary forest but also to enable ... [more ▼]

Today, many countries of South-East Asia know about the alarming state of the forests existing on their territory and all agree that it is essential to save the remaining primary forest but also to enable the regeneration of degraded areas, through natural or artificial reforestation. The conservation of tropical rainforests thus passes by the necessity to better understand the plant-animal interactions, and in particular, the seed dispersal process. While following a troop of pigtailed macaques (Macaca nemestrina leonina) accustomed to Man in Khao Yai National park (2 168 km ²), Thailand, we will bring important data relating to these seed dispersers potentially necessary but unfortunately vulnerable. Indeed, this vulnerable but little known species, seems to be essential to maintain forest diversity by dispersing many plant species, particularly those inaccessible to smaller frugivores. First results already show that they disperse many seed species, of all kind of size, in all forest types, from primary forest to secondary forest, thanks to various handling techniques. They also seem to show an adaptation in their daily travels according to resources availability. The next fieldworks will enable us to bring more precision in these results and their temporal variations and thus to conclude on the potential role of Macaca nemestrina in the tropical rainforest regeneration. [less ▲]

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See detailThe importance of pollen chemistry in evolutionary host shifts of bees
Vanderplanck, Maryse ULiege; Vereecken, Nicolas; Grumiau, Laurent et al

in Scientific Reports (2017)

Although bee-plant associations are generally maintained through speciation processes, host shifts have occurred during evolution. Understanding shifts between both phylogenetically and morphologically ... [more ▼]

Although bee-plant associations are generally maintained through speciation processes, host shifts have occurred during evolution. Understanding shifts between both phylogenetically and morphologically unrelated plants (i.e., host-saltation) is especially important since they could have been key processes in the origin and radiation of bees. Probably far from being a random process, such host-saltation might be driven by hidden constraints associated with plant traits. We selected two clades of oligolectic bees (i.e., Colletes succinctus group and Melitta leporina group) foraging on co-flowering but unrelated host-plants to test this hypothesis. We analyzed floral scent, floral color and chemical composition of pollen from host and non-host plants of these two clades. We did not find evidence for host-plant evolution in the Melitta leporina group driven by one of the assayed floral traits. On the contrary, hosts of the C. succinctus group display similar primary nutritive content of pollen (i.e., amino acids and sterols) but not similar floral scent or color, suggesting that shared pollen chemistry probably mediates saltation in this clade. Our study revealed that constraints shaping floral associations are diverse and clearly depend on species life-history traits, but evidence suggests that pollen chemistry may act as a major floral filter and guide evolutionary host-shifts. [less ▲]

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See detailImportance of post-transcriptional regulation of chemokine genes by oxidative stress.
JOSSE, Claire ULiege; Boelaert, J. R.; Best-Belpomme, M. et al

in Biochemical Journal (2001), 360(Pt 2), 321-33

The transcription factor, nuclear factor kappa B (NF-kappa B), is activated by various stimuli including cytokines, radiation, viruses and oxidative stress. Here we show that, although induction with H(2 ... [more ▼]

The transcription factor, nuclear factor kappa B (NF-kappa B), is activated by various stimuli including cytokines, radiation, viruses and oxidative stress. Here we show that, although induction with H(2)O(2) gives rise to NF-kappa B nuclear translocation in both lymphocyte (CEM) and monocyte (U937) cells, it leads only to the production of mRNA species encoding interleukin-8 (IL-8) and macrophage inflammatory protein 1 alpha in U937 cells. Under similar conditions these mRNA species are not observed in CEM cells. With the use of a transient transfection assay of U937 cells transfected with reporter constructs of the IL-8 promoter and subsequently treated with H(2)O(2), we show that (1) IL-8-promoter-driven transcription is stimulated in both U937 and CEM cells and (2) the NF-kappa B site is crucial for activation because its deletion abolishes activation by H(2)O(2). The production of IL-8 mRNA in U937 cells is inhibited by the NF-kappa B inhibitors clasto-lactacystin-beta-lactone and E-64D (l-3-trans-ethoxycarbonyloxirane-2-carbonyl-L-leucine-3-methyl amide) but requires protein synthesis de novo. Moreover, inhibition of the p38 mitogen-activated protein kinase also decreases the IL-8 mRNA up-regulation mediated by H(2)O(2). Taken together, these results show the importance of post-transcriptional events controlled by a p38-dependent pathway in the production of IL-8 mRNA in U937. The much lower activation of p38 in CEM cells in response to H(2)O(2) could explain the lack of stabilization of IL-8 mRNA in these cells. [less ▲]

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See detailImportance of quantitative return-to-field criteria
Schwartz, Cédric ULiege; Cordonnier, Caroline ULiege; Lehance, Cédric ULiege et al

Conference (2014, July 04)

Detailed reference viewed: 51 (10 ULiège)
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See detailImportance of recent extreme weather variation in Djibouti and need for impact quantification
Nour Ayeh, Moustapha; Mahamoud, Ayan; Saad, Osman et al

Poster (2014, February)

This analysis shows that the current rainfall deficit is exceptional and historically unique. The significant population migration induced by the drought to Djibouti city must be supervised, especially ... [more ▼]

This analysis shows that the current rainfall deficit is exceptional and historically unique. The significant population migration induced by the drought to Djibouti city must be supervised, especially during their spontaneous settling. This presented example confirms that current rainfall shortages and increasing temperature extremes are impactinglocal people who urgently need adaptation and DRR strategies. It is necessary to reduce exposure to hydrological risks of these affected populations, in order that victims of the drought are not carried away by a rainfall excess. [less ▲]

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See detailImportance of rheological properties when drying sludge in a fixed bed
Léonard, Angélique ULiege; Blandin, Gaëtan; Crine, Michel ULiege

in 4th Inter-American Drying Conference: Challenges for efficient drying processes (2009)

Detailed reference viewed: 38 (7 ULiège)
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See detailImportance of risk stratification models in cardiac surgery
Kolh, Philippe ULiege

in European Heart Journal (2006), 27(7), 768-769

This editorial refers to 'Comparison of 19 pre-operative risk strati. cation models in open-heart surgery'dagger by J. Nilsson et al., on page 867.

Detailed reference viewed: 17 (1 ULiège)
See detailThe importance of serial order short-term memory for native and second language lexical acquisition.
Majerus, Steve ULiege

Scientific conference (2008, June 18)

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See detailThe importance of short-term memory for order in dissociating short-term memory and language deficits
Attout, Lucie ULiege; VAN DER KAA, Marie-Anne ULiege; GEORGE, Mercédès ULiege et al

Poster (2011, May 27)

Selective verbal short-term memory (STM) deficits are rare, and when they appear, they are often associated with a history of aphasia, raising doubts about the selectivity of these deficits. We explore ... [more ▼]

Selective verbal short-term memory (STM) deficits are rare, and when they appear, they are often associated with a history of aphasia, raising doubts about the selectivity of these deficits. We explore here the distinction between STM for item information and STM for order information to separate STM and language impairments. Recent models of STM consider that STM for item information depends upon activation of the language system, and hence item STM deficits should be associated with language impairment. By contrast, STM for order information is considered to recruit a specific system, distinct from the language system. In this view, order STM should be impaired in patients with STM deficits that cannot be accounted for by language impairment. We applied this rationale to the exploration of STM profiles of patients MB and CG. Patient MB showed mild phonological impairment and associated STM deficits. As predicted, these were characterized by poor item STM but preserved order STM. Patient CG showed verbal STM deficits with no associated language deficits. His STM deficit was characterized by poor order STM but relatively preserved item STM. This study presents the first double dissociation between item and order STM deficits, demonstrating the necessity of this distinction for understanding selective STM impairment. [less ▲]

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See detailThe importance of short-term memory for order in dissociating short-term memory and language deficits.
Attout, Lucie ULiege; Majerus, Steve ULiege

Poster (2012, May)

Several studies explored the relationship between verbal short-term memory (STM) and numerical cognition, but with inconclusive findings. The present study re-explored this relationship, by adopting the ... [more ▼]

Several studies explored the relationship between verbal short-term memory (STM) and numerical cognition, but with inconclusive findings. The present study re-explored this relationship, by adopting the critical distinction between STM for item information (the items to be retained) and STM for order information (the order of the items within a list). We hypothesized that especially STM for order should be related to the development of numerical abilities, given that recent studies suggest the intervention of common processes during the representation of order information in STM and numerical tasks. We investigated item and order STM abilities and numerical processing abilities in 68 children during their third year in kindergarten. We observed that order STM abilities, but not item STM abilities, correlated significantly with performance on numerical order judgment and calculation tasks. These associations remained after control of interindividual differences in verbal and non-verbal cognitive efficiency. Our results suggest a specific relationship between order STM processes and numerical cognition, opening new perspectives for our understanding of the STM determinants of numerical cognition development. [less ▲]

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See detailThe importance of short-term memory for serial order in L2 learning.
Majerus, Steve ULiege

Conference (2013, September 03)

Detailed reference viewed: 10 (3 ULiège)
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See detailImportance of social companionship in the determination of health-related quality of life in hip and knee osteoarthrits
Ethgen, Olivier ULiege; Van Parijs, P.; Delhalle, S. et al

in Arthritis and Rheumatism (2001), 44(Suppl.1), 183

Detailed reference viewed: 10 (1 ULiège)
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See detailImportance of social companionship in the determination of health-related quality of life in hip and knee osteoarthrits
Ethgen, Olivier ULiege; Van Parijs, P.; Delhalle, S. et al

in Clinical Rheumatology (2001), 5(Suppl.1), 413

Detailed reference viewed: 18 (1 ULiège)
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See detailImportance of social companionship in the determination of health-related quality of life in hip and knee osteoarthrits
Ethgen, Olivier ULiege; Van Parijs, P.; Delhalle, S. et al

in Osteoarthritis and Cartilage (2001), 9(Suppl.B), 19-20

Detailed reference viewed: 9 (1 ULiège)
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See detailImportance of soft solution processing for advanced BaZrO3 materials
Robertz, B.; Boschini, Frédéric ULiege; Cloots, Rudi ULiege et al

in International Journal of Inorganic Materials (2001), 3(8), 1185-1187

Barium zirconate is an interesting material for refractory applications as well as a good substrate for the manufacturing of high temperature superconductors. However, its solid state synthesis requires ... [more ▼]

Barium zirconate is an interesting material for refractory applications as well as a good substrate for the manufacturing of high temperature superconductors. However, its solid state synthesis requires high temperature and provides inhomogeneous powder with a broad particle size distribution. In order to avoid these disadvantages, soft solution routes are of growing importance in the ceramic powder synthesis. Precipitation. decomposition of precursors, combustion techniques offer alternative ways to the solid state method. Advantages of these are a lower calcination temperature, production of homogeneous and fine monodisperse powders. The obtained powders have been characterised by XRD, IR, SEM and DTA/TG analysis. The influence of the synthesis conditions on the properties of BaZrO3 has been studied. (C) 2001 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailImportance of steroid receptor coactivators in the modulation of steroid action on brain and behavior
Charlier, Thierry ULiege

in Psychoneuroendocrinology (2009), 34

Steroid receptors such as estrogen and androgen receptors are nuclear receptors involved in the transcriptional regulation of a large number of target genes. Steroid-dependent protein expression in the ... [more ▼]

Steroid receptors such as estrogen and androgen receptors are nuclear receptors involved in the transcriptional regulation of a large number of target genes. Steroid-dependent protein expression in the brain controls a large array of biological processes including spatial cognition, copulatory behavior and neuroprotection. The discovery of a competition, or squelch- ing, between two different nuclear receptors introduced the notion that common cofactors may be involved in the modulation of transcriptional activity of nuclear receptors. These cofactors or coregulatory proteins are functionally divided into coactivators and corepressors and are involved in chromatin remodeling and stabilization of the general transcription machinery. Although a large amount of information has been collected about the in vitro function of these coregulatory proteins, relatively little is known regarding their physiological role in vivo, particularly in the brain. Our laboratory and others have demonstrated the importance of SRC-1 in the differentia- tion and activation of steroid-dependent sexual behaviors and the related neural genes. For example, we report that the inhibition of SRC-1 expression blocks the activating effects of exogenous testosterone on male sexual behaviors and increases the volume of the median preoptic area. Other coactivators are likely to be involved in the modulation in vivo of steroid receptor activity and it seems that the presence of a precise subset of coactivators could help define the phenotype of the cell by modulating a specific downstream pathway after steroid receptor activation. The very large number of coactivators and their association into preformed complexes potentially allows the determination of hundreds of different phenotypes. The study of the expression of the coactivator and their function in vivo is required to fully understand steroid action and specificity in the brain. [less ▲]

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See detailImportance of steroid receptor coregulators for neuronal phenotype determination: Modulation of steroid action
Charlier, Thierry ULiege

in Trabajos del Instituto Cajal (2009), LXXXII

Steroid receptors such as estrogen receptors alpha and beta and androgen receptors are transcription factors involved in the transcriptional regulation of a large number of target genes. Steroid-dependent ... [more ▼]

Steroid receptors such as estrogen receptors alpha and beta and androgen receptors are transcription factors involved in the transcriptional regulation of a large number of target genes. Steroid-dependent expression in the brain controls a large array of biological processes including spatial cognition, copulatory behavior and neuroprotection. The discovery of a competition, or squelching, between two different nuclear receptors introduced the notion that common cofactors might be involved in the modulation of transcriptional activity of nuclear receptors. These cofactors, which are now known as coactivators, are involved in chromatin remodeling and stabilization of the general transcription machinery. Since the characterization of the steroid receptor coactivator 1 or SRC-1, more than 100 different cofactors have been identified. Although an increasingly large amount of information has been collected about the in vitro function of these coregulatory proteins, relatively little is known regarding their physiological role in vivo, particularly in the brain. Our laboratory and others have demonstrated the importance of SRC-1 in the differentiation and activation of steroid-dependent sexual behaviors and the related neural genes. In Japanese quail, the inhibition of SRC-1 expression by intracerebroventricular antisense injections blocked the activating effects of exogenous testosterone on male sexual behaviors and the steroid-dependent vasotocine expression and increase of the median preoptic area volume defined by Nissl staining as well as by aromatase immunoreactivity. These data therefore strongly suggested that SRC-1 is required to modulate estrogen receptor dependent gene-expression. It is however interesting to note that steroid receptors and SRC-1 are not always colocalized. For example, both glial cells and neurons in the hippocampus express estrogen receptor alpha but SRC-1 is rarely observed in glia. It is therefore possible that estrogen receptor alpha in glial cell require another coactivator or set of coactivators to induce estrogen-dependent gene transcription. It has been suggested very recently that SRC-1 is associated with neuronal differentiation of neural stem cell derived from the ganglionic eminence of mouse embryos. These stem cells differentiating into glial cell (GFAP-positive) did not express SRC-1. The presence of a specific coactivator could therefore determine a specific cell phenotype (neuronal vs glial). Another coactivator, the coactivator-associated arginine methyl transferase 1 or CARM-1 seems to be important to keep progenitor cells in a dividing state. The inhibition of CARM-1 expression leads to neuronal differentiation. Neurogenesis can therefore offers an excellent model to define the spatio-temporal role of different coactivators. It is indeed possible to study a subset of coactivators associated to various stages phenotype determination (proliferation vs. differentiation). The study of neurogenesis in the dentate gyrus of the hippocampus in female adult rats shows that around 40 % of proliferative cells express SRC-1 or CARM-1. Interestingly, 70% of proliferative cells express SRC-1 but only a very few cells (<5%) express CARM-1. We are currently investigating the temporal pattern of expression of these two coactivators during the neurogenesis in the hilus and dentate gyrus. The expression of the coactivators CARM-1 and SRC-1 is analyzed in proliferating and differentiating cells. We expect that proliferating and differentiating cells will differentially express the two coactivators. It seems that the presence of a precise subset of coactivators could help defining the phenotype of the cell by modulating a specific downstream pathway after steroid receptor activation. The very large number of coactivators and their association into preformed complexes potentially allows the determination of hundreds of different phenotypes. The study of the expression of the coactivator and their function in vivo is required to fully understand steroid action and specificity in the brain. [less ▲]

Detailed reference viewed: 24 (3 ULiège)
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See detailImportance of structural damping in the dynamic analysis of compliant deployable structures
Dewalque, Florence ULiege; Rochus, Pierre ULiege; Bruls, Olivier ULiege

in Acta Astronautica (2015), 111

Compliant mechanisms such as tape springs are often used on satellites to deploy appendices, e.g. solar panels, antennas, telescopes and solar sails. Their main advantage comes from the fact that their ... [more ▼]

Compliant mechanisms such as tape springs are often used on satellites to deploy appendices, e.g. solar panels, antennas, telescopes and solar sails. Their main advantage comes from the fact that their motion results from the elastic deformation of structural components, unlike usual hinges or prismatic joints, the motion of which is dictated by contact surfaces. No actuators or external energy sources are required and the deployment is purely passive, which appears as a decisive feature for the design of low-cost missions with small satellites or cubesats. The mechanical behaviour of a tape spring is intrinsically complex and nonlinear involving buckling, hysteresis and self-locking phenomena. High-fidelity mechanical models are then needed to get a detailed understanding of the deployment process, improve the design and predict the actual behaviour in the space 0-g environment. In the majority of the previous works, dynamic simulations were performed without any physical representation of the structural damping. These simulations could be successfully achieved because of the presence of numerical damping in the transient solver. However, in this case, the dynamic response turns out to be quite sensitive to the amount of numerical dissipation, so that the predictive capabilities of the model are questionable. In this work based on numerical case studies, we show that the dynamic simulation of a tape spring can be made less sensitive to numerical parameters when the structural dissipation is taken into account. [less ▲]

Detailed reference viewed: 77 (17 ULiège)