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See detailThe Distribution of Tyrosine Hydroxylase in the Canary Brain: Demonstration of a Specific and Sexually Dimorphic Catecholaminergic Innervation of the Telencephalic Song Control Nulcei
Appeltants, D.; Ball, G. F.; Balthazart, Jacques ULiege

in Cell & Tissue Research (2001), 304(2), 237-59

Singing and the processing of auditory information related to song can be affected by experimental manipulations of catecholamine activity in the brain of zebra finches. We investigated, by ... [more ▼]

Singing and the processing of auditory information related to song can be affected by experimental manipulations of catecholamine activity in the brain of zebra finches. We investigated, by immunocytochemistry in the brain of male and female canaries, the distribution of tyrosine hydroxylase (TH), the rate-limiting step in the synthesis of catecholamines. Fibers immunoreactive for TH (TH-ir) were particularly abundant in the lobus parolfactorius, the paleostriatum primitivum, and the nucleus septalis lateralis. A high density of TH-ir basket-like structures was observed in the caudomedial neostriatum, an area involved in song perception and recognition. In most males, a high density of TH-ir fibers outlined the telencephalic song control nuclei including the high vocal center, the nucleus robustus archistriatalis, the nucleus interfascialis, the lateral and medial parts of the magnocellular nucleus of the anterior neostriatum, and area X of the lobus parolfactorius. The higher density of fibers immunoreactive for TH in these nuclei, compared with the surrounding telencephalon, supports the notion that the morphological evolution of the song control nuclei was accompanied by a neurochemical specialization. This specific innervation of the song control regions was, in general, not found in females. The specific presence of high densities of TH-ir fibers in the song system of male canaries and the sex difference of this innervation provide anatomical evidence in support of the claim that dopamine and/or norepinephrine play important roles in the modulation of song learning and production. [less ▲]

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See detailDistribution of uncertainties at the municipality level for flood risk modelling along the river Meuse: implications for policy-making
Pirotton, Michel ULiege; Stilmant, Frédéric; Erpicum, Sébastien ULiege et al

Conference (2016, April)

Flood risk modelling has been conducted for the whole course of the river Meuse in Belgium. Major cities, such as Liege (200,000 inh.) and Namur (l 10,000 inh.), are located in the floodplains of river ... [more ▼]

Flood risk modelling has been conducted for the whole course of the river Meuse in Belgium. Major cities, such as Liege (200,000 inh.) and Namur (l 10,000 inh.), are located in the floodplains of river Meuse. Particular attention has been paid to uncertainty analysis and its implications for decision-making. The modelling chain contains flood frequency analysis, detailed 2D hydraulic computations, damage modelling and risk calculation. The relative importance of each source of uncertainty to the overall results uncertainty has been estimated by considering several alternate options for each step of the analysis; different distributions were considered in the flood frequency analysis; the influence of modelling assumptions and boundary conditions (e.g., steady vs. unsteady) were taken into account for the hydraulic computation; two different landuse classifications and two sets ofdamage functions were used; the number of exceedance probabilities involved in the risk calculation (by integration of the risk-curves) was varied. In addition, the sensitivity of the results with respect to increases in flood discharges \vas assessed. The considered increases are consistent with a "wet" climate change scenario for the time horizons 202l~2050 and 2071-2100 (Detrembleur et al., 2015). The results of hazard computation differ significantly between the upper and lower parts of the course of river Meuse in Belgium. In the former, inundation extents grow gradually as the considered flood discharge is increased (i.e. the exceedance probability is reduced), while in the downstream part, protection structures (mainly concrete walls) prevent inundation for flood discharges corresponding to exccedance probabilities of 0.01 and above (in the present climate). For higher discharges, large inundation extents are obtained in the floodplains. The highest values of risk (mean annual damage) are obtained in the municipalities which undergo relatively frequent flooding (upper part of the river), as well as in those of the downstream part of the Meuse in which flow depths in the urbanized floodplains are particularly high when inundation occurs. This is the case of the city of Liege, as a result of a subsidence process following former mining activities. For a given climate scenario, the uncertainty ranges affecting flood risk estimates are significant; but not so much that the results for the different municipalities would overlap substantially. Therefore, these uncertainties do not hamper prioritization in terms of allocation of risk reduction measures at the municipality level. In the present climate, the uncertainties arising from flood frequency analysis have a negligible influence in the upper part of the river, while they have a considerable impact on risk modelling in the lower part, where a threshold effect was observed due to the flood protection structures (sudden transition from no inundation to massive flooding when a threshold discharge is exceeded). Varying the number of exceedance probabilities in the integration of the risk curve has different effects for different municipalities; but it does not change the ranking of the municipalities in terms of flood risk. For the other scenarios, damage estimation contributes most to the overall uncertainties. As shown by this study, the magnitude of the uncertainty and its main origin vary in space and in time. This emphasizes the paramount importance of conducting distributed uncertainty analyses. In the considered study area, prioritization of risk reduction means can be reliably performed despite the modelling uncertainties. [less ▲]

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See detailDistribution of varicella-zoster virus and herpes simplex virus in disseminated fatal infections
Nikkels, Arjen ULiege; Delvenne, Philippe ULiege; Sadzot-Delvaux, Catherine ULiege et al

in Journal of Clinical Pathology (1996), 49(3), 243-248

AIMS: To study the cutaneous and visceral distribution of herpes simplex virus (HSV) and varicella zoster virus (VZV) in fatal infections. METHODS: Standard histology, immunohistochemistry (monoclonal ... [more ▼]

AIMS: To study the cutaneous and visceral distribution of herpes simplex virus (HSV) and varicella zoster virus (VZV) in fatal infections. METHODS: Standard histology, immunohistochemistry (monoclonal antibodies VL8 and VL2 and polyclonal antibody IE63 directed against VZV; monoclonal antibodies IBD4 and HH2 and polyclonal antibodies directed against HSVI and HSVII) and in situ hybridisation (anti-HSV and anti-VZV probes) were applied to formalin fixed, paraffin wax sections. RESULTS: On histological examination, Herpesviridae infection was evident in various organs including the lungs, liver and skin. In addition, immunohistochemistry and in situ hybridisation revealed the presence of HSV and VZV antigens and nucleic acids in several cell types and tissues showing no cytopathological alterations suggestive of Herpesviridae infection. The organs with histological evidence of infection also contained VZV or HSV antigens and their genes. CONCLUSIONS: These findings suggest that organ failure in disseminated VZV and HSV infections is primarily caused by HSV or VZV induced cell damage and lysis. They also indicate that immunohistochemistry and in situ hybridisation can provide an accurate, type-specific diagnosis on formalin fixed, paraffin wax embedded tissue even when classic histological and cytological characteristics are lacking. [less ▲]

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See detailDistribution of varicella-zoster virus DNA and gene products in tissues of a first-trimester varicella-infected fetus.
Nikkels, Arjen ULiege; Delbecque, Katty ULiege; Pierard, Gérald ULiege et al

in Journal of Infectious Diseases (2005), 191(4), 540-5

Precise information about varicella-zoster virus (VZV) infection in first-trimester fetuses remains sketchy. After varicella infection was diagnosed in a woman, her 12-week-old fetus was aborted and was ... [more ▼]

Precise information about varicella-zoster virus (VZV) infection in first-trimester fetuses remains sketchy. After varicella infection was diagnosed in a woman, her 12-week-old fetus was aborted and was investigated, by histological examination, virus culturing, polymerase chain reaction, in situ hybridization (ISH), and immunohistochemistry (IHC), for the presence of VZV infection. Only the results of the histological examination suggested the presence of alpha -herpesvirus infection, in the gastrointestinal tract and liver; results of ISH were positive for VZV, and results of IHC staining were positive for intermediate early protein 63 (IE63) but negative for glycoprotein E (gE), in the dorsal root ganglia (DRG), meninges, gastrointestinal tract, pancreas, smooth muscle, liver, and placental trophoblast, indicating the presence of a nonproductive, latency-like VZV infection. Only the gastrointestinal tract and liver exhibited simultaneous staining for IE63 and gE, a result suggesting that active replication of VZV was present. In conclusion, widespread nonproductive VZV infection in the absence of histological clues is an early event in VZV infection in fetuses. The observed gene-expression pattern in most tissues resembles that of latent VZV infection in DRG. Latency-like infection in nonneural cell types may potentially reactivate, leading to multifocal necrosis, fibrosis, and dystrophic calcifications, as observed in advanced congenital varicella syndrome. [less ▲]

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See detailDistribution of varicella-zoster virus gpI and gpII and corresponding genome sequences in the skin
Nikkels, Arjen ULiege; Delvenne, Philippe ULiege; Debrus, S. et al

in Journal of Medical Virology (1995), 46(2), 91-96

In the course of varicella-zoster virus (VZV) infection, some viral capsid antigens are found in the epidermis and dermis. The aim of this study was to investigate the localisation of two major VZV ... [more ▼]

In the course of varicella-zoster virus (VZV) infection, some viral capsid antigens are found in the epidermis and dermis. The aim of this study was to investigate the localisation of two major VZV glycoproteins (gpI and gpII) and of their respective genes in the skin. The distribution of VZV gpI and II in 27 formalin fixed paraffin embedded skin biopsies from herpes tester eruptions were compared by immunohistochemistry. Double immunostaining was carried our to identify infected cells. The presence of viral nucleic acids coding for gpI and gpII was examined by in situ hybridisation. The distribution of gpI and gpII and their corresponding genome sequences was similar in the epidermis, gpI and gpII were also detected in dermal FXIIIa positive dendrocytes, in Mac 387 and CD68 positive macrophages, and in perineural and endothelial cells. However, the corresponding viral nucleic acids were rarely and barely detected in these cells of the dermis. It is concluded that VZV infection of epithelial cells follows a different course than in dermal cells. (C) 1995 Wiley-Liss, Inc. [less ▲]

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See detailDistribution of vortex lattice melting temperatures in mixed state diagram of Bi2212 tapes
Pekala, M.; Bougrine, Hassan ULiege; Gadomski, W. et al

in Physica C (1998), 303(3-4), 169-176

The electrical resistivity in the mixed state of Bi2212 tape superconductors can be accurately reconstructed for values below approximately a half of the normal state value of resistivity, assuming a ... [more ▼]

The electrical resistivity in the mixed state of Bi2212 tape superconductors can be accurately reconstructed for values below approximately a half of the normal state value of resistivity, assuming a Gaussian distribution for the vortex lattice melting temperatures. The magnetic field dependences of the distribution width and of the dB(c2)/dT parameter were calculated. Moreover the vortex liquid viscosity coefficient was determined between the vortex lattice melting temperature and T-c at various magnetic fields. It is pointed out that the vortex lattice melting transition should not be confused with the irreversibility line of magnetic studies nor with the percolation temperature line for electrical resistivity. (C) 1998 Elsevier Science B,V. All rights reserved. [less ▲]

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See detailLa distribution par des véhicules électriques
Bay, Maud ULiege; Limbourg, Sabine ULiege

Scientific conference (2016, May 25)

The objective of vehicle routing problems is to design a set of efficient vehicle routes to provide goods from a depot to a set of customers satisfying specific constraints. Classical variants of these ... [more ▼]

The objective of vehicle routing problems is to design a set of efficient vehicle routes to provide goods from a depot to a set of customers satisfying specific constraints. Classical variants of these problems consider that routes are performed by internal combustion engine vehicles. These vehicles have a long and easy-to-restore driving range. However, due to the short driving range, long battery recharging times and the limited availability of charging infrastructure, routing algorithms for EV need to be developped. Maximizing the driving range of the vehicle leads to an examination of the main factors in energy consumption which are: the mass of the vehicle and its payload, engine efficiency, vehicle speed, the drive pattern, road grade, and vehicle recharge ability while driving. Results from this research will provide an optimal management of urban logistics where night delivery, through the use of those silent vehicles, remains one of the main benefits. [less ▲]

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See detailDistribution patterns and indicator species of butterfly assemblages of wet meadows in southern Belgium
Sawchik, Javier; Dufrêne, Marc ULiege; Lebrun, Philippe

in Belgian Journal of Zoology (2005), 135(1), 43-52

Focal species are a valuable tool for proposing and evaluating management practices for biodiversity conservation. Assemblages of indicator species could be used to cover a wide range of habitats. We ... [more ▼]

Focal species are a valuable tool for proposing and evaluating management practices for biodiversity conservation. Assemblages of indicator species could be used to cover a wide range of habitats. We identified the main patterns of variation in butterfly assemblages on a diverse set of wet meadows in southern Belgium. We used multivariate techniques to identify the butterfly assemblages and the species that characterize these habitats. Three main assemblages were identified, based principally on the dominance of five butterfly species : Brenthis ino, Closiana selene, Lycaena helle, Lycaena hippothoe and Proclossiana eunomia. These are indicator species of different habitats structured along a vegetation gradient. This gradient is partially determined by altitude and edaphic factors (base-richness, pH, fertility). We assume that focusing the conservation practices upon these species will promote the preservation of a wide range of organisms inhabiting the wet meadows. [less ▲]

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See detailDistribution patterns of Caprella tavolarensis (Crustacea: Amphipoda) in the Tavolara-Punta Coda Cavallo Marine Protected Area.
Sturaro, Nicolas ULiege; Gobert, Sylvie ULiege; Lepoint, Gilles ULiege et al

in Biologia Marina Mediterranea (2011), 18(1), 290-291

Distribution patterns of Caprella tavolarensis was investigated at the tavolara-punta Coda Cavallo Marine protected area. results revealed that C. tavolarensis abundance may exhibit spatial patterns ... [more ▼]

Distribution patterns of Caprella tavolarensis was investigated at the tavolara-punta Coda Cavallo Marine protected area. results revealed that C. tavolarensis abundance may exhibit spatial patterns associated with the protection status of the zones, highlighting the importance of totally protected areas in species conservation and management. [less ▲]

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See detailLa distribution spatiale des Acanthaceae dans les secteurs phytogéographiques de Ndjele (1988) en RD Congo
Koffi, K J; Boyemba, F; Ndjele, M et al

in Annales de la Faculté des Sciences, Université de Kisangani (2008), 13

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See detailDistribution spatiale et préférences écologiques chez les Diplopodes du sol
Kime, R. D.; Dufrêne, Marc ULiege; Wauthy, G. et al

in Mémoires de la Société Royale d'Entomologie de Belgique (1992), 35

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See detailDistribution stratigraphique et géographique d' Hymenozonotriletes lepidophytus Kedo, cf. Hymenozonotriletes pusillites Kedo et des assemblages Tournaisiens.
Streel, Maurice ULiege

in Streel, Maurice; Wagner, R.H. (Eds.) Colloque sur la Stratigraphie du Carbonifère, (1971)

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See detailDistribution, leaching and flux measurements of contaminants in the vadose zone of industrial contaminated sites: a review
Fernandez de Vera, Natalia ULiege; Vanclooster, Marnik; Brouyère, Serge ULiege

Report (2012)

This document is a review of state of science regarding flux measurement technologies in the vadose zone. Initially, a description of distribution and leaching of inorganic contaminants in the vadose zone ... [more ▼]

This document is a review of state of science regarding flux measurement technologies in the vadose zone. Initially, a description of distribution and leaching of inorganic contaminants in the vadose zone is provided. Such description is followed by a review of vadose zone techniques that are applied for measuring contaminant fluxes. At the end of the document the applicability of such techniques to industrial contaminated sites is discussed. [less ▲]

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See detailDistribution, origin and cycling of carbon in the Tana River (Kenya): a dry season basin-scale survey from headwaters to the delta
Bouillon, S.; Abril, G.; Borges, Alberto ULiege et al

in Biogeosciences (2009), 6

The Tana River basin (TRB) is the largest in Kenya (_120 000 km2). We conducted a survey during the dry season throughout the TRB, analyzing a broad suite of biogeochemical parameters. Biogeochemical ... [more ▼]

The Tana River basin (TRB) is the largest in Kenya (_120 000 km2). We conducted a survey during the dry season throughout the TRB, analyzing a broad suite of biogeochemical parameters. Biogeochemical signatures in headwater streams were highly variable. Along the middle and lower river course, total suspended matter (TSM) concentrations increased more than 30-fold despite the absence of tributary inputs, indicating important resuspension events of internally stored sediment. These resuspended sediment inputs were characterized by a lower and 14C-depleted OC content, suggesting selective degradation of more recent material during sediment retention. Masinga Dam (a large reservoir on the upper river) induced a strong nutrient retention (_50% for inorganic N, _72% for inorganic phosphate, and _40% for dissolved silicate). Moreover, while DOC pools and _13C signatures were similar above, in and below the reservoir, the POC pool in Masinga surface waters was dominated by 13C-depleted phytoplankton, which contributed to the riverine POC pool immediately below the dam, but rapidly disappeared further downstream, suggesting rapid remineralization of this labile C pool in the river system. Despite the generally high turbidity, the combination of relatively high oxygen saturation levels, low _18O signatures of dissolved O2 (all <+24.2‰), and the relatively low pCO2 values suggest that in-stream primary production was significant, even though pigment data suggest that phytoplankton makes only a minor contribution to the total POC pool in the Tana River. [less ▲]

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See detailA distribution-free joint test and one-directional robust tests for random individual effects and heteroscedasticity allowing for unbalanced panels
Lejeune, Bernard ULiege

Conference (1999, August 29)

This paper proposes a convenient testing procedure designed for detecting, from preliminary (pooled) OLS estimation of the model, the possible simultaneous presence of indivi-dual effects and ... [more ▼]

This paper proposes a convenient testing procedure designed for detecting, from preliminary (pooled) OLS estimation of the model, the possible simultaneous presence of indivi-dual effects and heteroscedasticity in the error of a linear panel data regression model. The proposed testing procedure consists in (1) a distribution-free and allowing for unbalanced panel joint pseudo-LM test of the null of no individual effect and no heteroscedasticity and (2) a BMCP based on distribution-free and again allowing for unbalanced panel robust one-directional pseudo-LM tests for identifying the source(s) of departure from the joint null when it is rejected. An empirical example illustrates the usefulness of the testing procedure. [less ▲]

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See detailA distribution-free joint test for random individual effects and heteroscedasticity allowing for incomplete panels
Lejeune, Bernard ULiege

Conference (1999, June 04)

This paper proposes a convenient testing procedure designed for detecting, from preliminary (pooled) OLS estimation of the model, the possible simultaneous presence of individual effects and ... [more ▼]

This paper proposes a convenient testing procedure designed for detecting, from preliminary (pooled) OLS estimation of the model, the possible simultaneous presence of individual effects and heteroscedasticity in the error of a linear panel data regression model. The proposed testing procedure consists in (1) a distribution-free and allowing for unbalanced panel joint pseudo-LM test of the null of no individual effect and no heteroscedasticity and (2) a BMCP based on distribution-free and again allowing for unbalanced panel robust one-directional pseudo-LM tests for identifying the source(s) of departure from the joint null when it is rejected. An empirical example illustrates the usefulness of the testing procedure. [less ▲]

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