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See detailDistribution patterns and indicator species of butterfly assemblages of wet meadows in southern Belgium
Sawchik, Javier; Dufrêne, Marc ULg; 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 ULg; Gobert, Sylvie ULg; Lepoint, Gilles ULg 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 ULg; Wauthy, G. et al

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

Detailed reference viewed: 19 (1 ULg)
See detailDistribution stratigraphique et géographique d' Hymenozonotriletes lepidophytus Kedo, cf. Hymenozonotriletes pusillites Kedo et des assemblages Tournaisiens.
Streel, Maurice ULg

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 ULg; Vanclooster, Marnik; Brouyère, Serge ULg

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 ULg 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 ULg

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 ULg

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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See detailDistributions des valeurs extrêmes
Donneau, Anne-Françoise ULg

Master's dissertation (2002)

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See detailThe distributions of the OH (Δv=1) and (Δv=2) emissions on the Venus nightside
Soret, Lauriane ULg; Gérard, Jean-Claude ULg; Piccioni, Giuseppe et al

Conference (2010, September)

The presence of OH was detected in the spectrum of the Venus mesosphere observed at the limb with the VIRTIS instrument on board the Venus Express spacecraft [3]. The (1-0) and (2-1) transitions at 2.80 ... [more ▼]

The presence of OH was detected in the spectrum of the Venus mesosphere observed at the limb with the VIRTIS instrument on board the Venus Express spacecraft [3]. The (1-0) and (2-1) transitions at 2.80 and 2.94 mm, respectively and the (2-0) band at 1.43 mm were clearly identified. The results of this study show that a correlation is observed between the emissions associated to the Δv=1 and the Δv=2 sequences. [less ▲]

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See detailThe distributions of the OH Meinel and O[SUB][/SUB](a[SUP]1[/SUP]Δ-X[SUP]3[/SUP]Σ) nightglow emissions in the Venus mesosphere based on VIRTIS observations
Gérard, Jean-Claude ULg; Soret, Lauriane ULg; Saglam, Adem ULg et al

in Advances in Space Research (2010), 45

O[SUB][/SUB](a[SUP]1[/SUP]Δ) and recently discovered OH Meinel nightglow emissions have been observed at the limb with the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS-M) instrument on board ... [more ▼]

O[SUB][/SUB](a[SUP]1[/SUP]Δ) and recently discovered OH Meinel nightglow emissions have been observed at the limb with the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS-M) instrument on board the Venus Express satellite. Hydroxyl bands belonging to Δv=1 sequence between 2.60and3.14μm and to Δv=2 sequence at 1.40-1.46μm have been unambiguously identified. In this study, we analyze the statistical distribution of the Δv=1 OH Meinel band sequence and the a[SUP]1[/SUP]Δ[SUB]g[/SUB]-X[SUP]3[/SUP]Σ (0-0) band of the O[SUB][/SUB] Infrared Atmospheric bands at 1.27 μm. We also present an analysis of the correlation between the two emissions. From a statistical point of view, we find that the limb intensity of both emissions reach their maximum value near the antisolar point, while they are significantly dimmer in the vicinity of the terminator. The average altitude of the limb emissions peaks are 95.3 ± 3 km and 96 ± 2.7 km, respectively for the OH Δv=1 sequence and O[SUB][/SUB](a[SUP]1[/SUP]Δ) emissions. The average intensities are 0.41 ± 0.37 MR and 28 ± 22 MR, respectively, corresponding to a mean ratio of about 70. The altitude of the OH nightglow layer is closely related to that of the O[SUB][/SUB](a[SUP]1[/SUP]Δ) emission and some level of co-variation of the maximum intensity along the line of sight is observed. It is suggested that the global subsolar to antisolar circulation plays a key in the control of both airglows by carrying oxygen atoms from the day to the night side of the planet. The O atoms recombine to produce O[SUB][/SUB](a[SUP]1[/SUP]Δ) molecules and they also act as precursors of ozone whose reaction with H produces excited hydroxyl. [less ▲]

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See detailDistributive contact lattices with nontangential part-of relations
Raskin, Julien ULg

Conference (2015, June 23)

In a Boolean algebra, the "contact" and "nontangential part-of" relations are linked and interdefinable thanks to the complement. These relations yield on the Stone dual of the algebra two closed ... [more ▼]

In a Boolean algebra, the "contact" and "nontangential part-of" relations are linked and interdefinable thanks to the complement. These relations yield on the Stone dual of the algebra two closed relations that appear to be the same. In a distributive lattice, the contact and nontangential part-of relations also yield dual closed relations on the Priestley dual. However, as the link between them is lost, these relations are not equal anymore. We explore the conditions linking the contact and nontangential part-of relations one should add in order to recover these relations knowing the intersection of their dual. [less ▲]

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See detailThe distributive effects of shifting from public to private provision of retirement income
Delhausse, B.; Pestieau, Pierre ULg; Perelman, Sergio ULg

in Berghman, J.; Cantillon, B. (Eds.) The European Face of Social Security (1993)

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See detailDistributive Justice and Social Equity: Québécois and French Students’ Patterns of Social Justice Perception
Fournier, Bernard ULg; Hudon, Raymond

Conference (1998, July 15)

Multivariate analysis, like correspondence analysis and hierarchical ascendant classification, allow us not only to reduce information collected with several questions, but in a more significant way, to ... [more ▼]

Multivariate analysis, like correspondence analysis and hierarchical ascendant classification, allow us not only to reduce information collected with several questions, but in a more significant way, to stress on the plurality of behaviors and cognitions which coexists inside a given population. However, the theoretical consequences of these possibilities are not always fully used, especially if the objective of the research is to compare survey results between two populations: isn’t it more convenient to keep one or two global images and to suggest hypotheses from this representation? First analyses of the survey results on Distributive Justice and the role of the State show us that French students seem to stress more on the role of State in society and economics than their Québécois counterparts. But many subtleties are hidden by this single image and in fact, for students who filled the survey in 1996, many patterns have to be presented. With a more precise portrait, we can suggest that even a strong economical context like the one we experience today doesn’t lead to homogeneous attitudes for student populations : construction processes of individual’ s reference are still important to study. [less ▲]

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See detailDistributive Justice and Social Equity: Québécois and French Students' Perceptions
Hudon, Raymond; Fournier, Bernard ULg

Conference (1996, July)

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