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See detailDiscrimination of parasitized aphids by a hoverfly predator: effects on larval performance, foraging, and oviposition behavior
Almohamad, Raki; Verheggen, François ULiege; Francis, Frédéric ULiege et al

in Entomologia Experimentalis et Applicata (2008), 128(1), 73-80

The choice of oviposition site by female aphidophagous predators is crucial for offspring performance, especially in hoverflies whose newly hatched larvae are unable to move over large distance. Predator ... [more ▼]

The choice of oviposition site by female aphidophagous predators is crucial for offspring performance, especially in hoverflies whose newly hatched larvae are unable to move over large distance. Predator and parasitoid interactions within the aphidophagous guild are likely to be very important in influencing the choices made by predatory hoverfly females. In the present study, the foraging and oviposition behavior of the aphidophagous hoverfly Episyrphus balteatus DeGeer (Diptera: Syrphidae) was investigated with respect to the parasitized state of its aphid prey, Acyrthosiphon pisum Harris (Homoptera: Aphididae), that were parasitized by Aphidius ervi Haliday (Hymenoptera: Aphidiidae). We also recorded the number of eggs laid by hoverfly females when subjected to parasitized aphids. Furthermore, we studied the influence of being fed with parasitized aphids on hoverfly larval performance. Hoverfly females did not exhibit any preference for plants infested with unparasitized or aphids parasitized for 7 days. On the other hand, plants infested with mummies or exuvia were less attractive for E. balteatus. These results were correlated with (i) the number of eggs laid by E. balteatus females and (ii) larval performance. Thus, our results demonstrate that E. balteatus behavior is affected by parasitoid presence through their exploitation of aphid colonies. Indeed, hoverfly predators select their prey according to the developmental state of the parasitoid larvae. [less ▲]

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See detailDiscrimination of pure grassland species using NIR Hyperspectral Imaging
Dale, Laura ULiege; Bogdan, Anca Dorina; Pacurar, Florin Simion et al

Poster (2012, June 03)

The objective of this study was to discriminate by hyperspectral imaging system, SWIR ImSpector N25E, different pure grassland species (Festuca rubra L., Trifolium repens L., Agrostis capillaris L ... [more ▼]

The objective of this study was to discriminate by hyperspectral imaging system, SWIR ImSpector N25E, different pure grassland species (Festuca rubra L., Trifolium repens L., Agrostis capillaris L., Hieracium aurantiacum L., Arnica montana L.) into grassland species mixtures. All the samples were collected from natural meadows of the National Apuseni Park, Apuseni Mountains, Gârda area (Romania). The samples were air-dried, then prepared using the protocol for NIRS analysis adapted on the scanning linear system. For images acquisition, the Hyper See program was used. Then a model build under MatLab (PLS–DA) was used to discriminate pure species from the mixtures of two or three species. This analysis was carried out in order to see, on images obtained previously from the floristic composition of experimental parcels, if the pure species are or are not recognized according to the spectral data base. More than 99% correct predictions for species discrimination were obtained. This study should guide us to verify if a toxic species is present or not in natural meadows used as food for animals. The floristic composition of a meadow can be determinate only if we have in the data base, spectra for each identified species, as being part of the mixture. [less ▲]

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See detailDiscrimination of shifts in a soil microbial community assosciated with TNT-contamination using a functional ANOVA of 16S rRNA hybridized to oligonucleotide microarrays
Eyers; Smoot, J. C.; Smoot, L. M. et al

in Environmental Science & Technology (2006), 40

A functional ANOVA analysis of the thermal dissociation of RNA hybridized to DNA microarrays was used to improve discrimination between two soil microbial communities. Following hybridization of in vitro ... [more ▼]

A functional ANOVA analysis of the thermal dissociation of RNA hybridized to DNA microarrays was used to improve discrimination between two soil microbial communities. Following hybridization of in vitro transcribed 16S rRNA derived from uncontaminated and 2,4,6- trinitrotoluene contaminated soils to an oligonucleotide microarray containing group- and species-specific perfect match (PM) probes and mismatch (MM) variants, thermal dissociation was used to analyze the nucleic acid bound to each PM-MM probe set. Functional ANOVA of the dissociation curves generally discriminated PM-MM probe sets when Td values (temperature at 50% probe-target dissociation) could not. Maximum discrimination for many PM and MM probes often occurred at temperatures greater than theTd. Comparison of signal intensities measured prior to dissociation analysis from hybridizations of the two soil samples revealed significant differences in domain-, group-, and species-specific probes. Functional ANOVA showed significantly different dissociation curves for 11 PM probes when hybridizations from the two soil samples were compared, even though initial signal intensities for 3 of the 11 did not vary. [less ▲]

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See detailDiscrimination of three genetically close Aspergillus species by using high resolution melting analysis applied to indoor air as case study.
Libert, Xavier; Packeu, Ann; Bureau, Fabrice ULiege et al

in BMC Microbiology (2017), 17(1), 84

BACKGROUND: Indoor air pollution caused by fungal contamination is suspected to have a public health impact. Monitoring of the composition of the indoor airborne fungal contaminants is therefore important ... [more ▼]

BACKGROUND: Indoor air pollution caused by fungal contamination is suspected to have a public health impact. Monitoring of the composition of the indoor airborne fungal contaminants is therefore important. To avoid problems linked to culture-dependent protocols, molecular methods are increasingly being proposed as an alternative. Among these molecular methods, the polymerase chain reaction (PCR) and the real-time PCR are the most frequently used tools for indoor fungal detection. However, even if these tools have demonstrated their appropriate performance, some of them are not able to discriminate between species which are genetically close. A solution to this could be the use of a post-qPCR high resolution melting (HRM) analysis, which would allow the discrimination of these species based on the highly accurate determination of the difference in melting temperature of the obtained amplicon. In this study, we provide a proof-of-concept for this approach, using a dye adapted version of our previously developed qPCR SYBR(R)Green method to detect Aspergillus versicolor in indoor air, an important airborne fungus in terms of occurrence and cause of health problems. Despite the good performance observed for that qPCR method, no discrimination could previously be made between A. versicolor, Aspergillus creber and Aspergillus sydowii. METHODS: In this study, we developed and evaluated an HRM assay for the discrimination between A. versicolor, Aspergillus creber and Aspergillus sydowii. RESULTS: Using HRM analysis, the discrimination of the 3 Aspergillus species could be made. No false positive, nor false negatives were observed during the performance assessment including 20 strains of Aspergillus. The limit of detection was determined for each species i.e., 0.5 pg of gDNA for A. creber and A. sydowii, and 0.1 pg of gDNA for A. versicolor. The HRM analysis was also successfully tested on environmental samples. CONCLUSION: We reported the development of HRM tools for the discrimination of A. versicolor, A. creber and A. sydowii. However, this study could be considered as a study case demonstrating that HRM based on existing qPCR assays, allows a more accurate identification of indoor air contaminants. This contributes to an improved insight in the diversity of indoor airborne fungi and hence, eventually in the causal link with health problems. [less ▲]

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See detailDiscrimination of two geographically distinct populations of sea bass Dicentrarchus labrax, using stable isotopic signatures of mercury (δ202Hg, Δ199Hg)
Cransveld, Alice ULiege; Amouroux, David; Koutrakis, Emmanuil et al

Poster (2014, May 15)

Despite the reduction of mercury (Hg) emissions in Europe in the last decades, Hg emissions are increasing worldwide and concentrations found in some marine predators remain high. This raises questions on ... [more ▼]

Despite the reduction of mercury (Hg) emissions in Europe in the last decades, Hg emissions are increasing worldwide and concentrations found in some marine predators remain high. This raises questions on mercury's biogeochemical cycle at both local and global scale. In the present work, we investigate the possibility to use mercury isotopic signature in fish as a tool to discriminate different polluted areas and potential pollution sources. Indeed, Hg can exhibit both mass-dependent (MDF) and mass-independent fractionation (MIF). While MDF may occur during biological cycling inter alia and could be used to understand bioaccumulation processes, MIF provides a unique fingerprint of specific chemical pathways, such as photochemical transformations. In this context, information provided by Hg isotopes would help to improve environmental management strategies. A preliminary set of four and ten juvenile common sea bass, Dicentrarchus labrax were collected from the North Sea and the Aegean Sea respectively. T-Hg was analysed by direct mercury analyser (DMA), speciation by gas chromatography inductively coupled plasma mass spectrometer (GC-ICP-MS) and Hg isotope analysis were performed using cold vapour generation with multicollector ICP-MS. Total Hg concentrations in all tissues were higher in individuals from the North Sea ( Hgtot muscle=1,14 ± 0,48 mg.kg-1 dw) than from Greece (0,60 ± 0,06 mg.kg-1 dw). Speciation analysis shows that MeHg is the predominant form of Hg in muscle (89% MeHg on average) but not in liver (51% MeHg on average). Isotopic mass dependent values (δ202Hg) values were always higher in muscle than in liver and related to Hg species distribution. For mass independent isotopic signature, sea bass from the Aegean Sea had a systematically higher Δ199Hg value than individuals from the North sea (e.g.: 0,56 ± 0,05‰ and 0,32 ± 0,06‰ respectively in muscle). While mass dependent isotopic signature probably reflects some internal Hg metabolism, mass independent isotopic signature seems definitely site dependent. Such isotopic discrimination might be in agreement with difference in both mercury sources and cycling in the North and Aegean Seas. These preliminary results indicate that Hg isotopes may thus help to discriminate fish from different areas. This promising outcome must be further confirmed by extending the number of individuals and locations to be investigated. [less ▲]

Detailed reference viewed: 96 (10 ULiège)
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See detailDiscrimination positive et mobilité scolaire
Bouchat, Thérèse-Marie; Delvaux, Bernard; Hindryckx, Geneviève ULiege

Report (2005)

Detailed reference viewed: 80 (8 ULiège)
See detailDiscrimination self/non-self
Heinen, Ernst ULiege

in Encyclopedia of Life Sciences (2005)

Detailed reference viewed: 18 (4 ULiège)
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See detailDiscrimination thresholds of the reverberation in large volumes by naïve listeners
Billon, Alexis ULiege; Embrechts, Jean-Jacques ULiege

in Proceedings of the Acoustics 2012 Nantes conference (2012, April)

Detailed reference viewed: 37 (0 ULiège)
See detailDiscriminations "ethno-raciales": comprendre, pour agir dans la relation d'aide?
Collin, Jonathan ULiege

Scientific conference (2017)

Cette conférence a d'abord examiné l'évolution sémantique observée - du racisme aux discriminations - et la manière de concevoir l'adjectif "ethno-raciales" que j'y associe. Quelques données chiffrées ... [more ▼]

Cette conférence a d'abord examiné l'évolution sémantique observée - du racisme aux discriminations - et la manière de concevoir l'adjectif "ethno-raciales" que j'y associe. Quelques données chiffrées relatives aux discriminations en Belgique et en Europe furent ensuite présentées. Enfin, une analyse en termes de gestion publique du stigmate et des interactions - interethniques - en face à face (Erving Goffman notamment) fut proposée. [less ▲]

Detailed reference viewed: 34 (6 ULiège)
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See detailLes discriminations à l'école
Italiano, Patrick ULiege; Jacquemain, Marc ULiege

Report (2014)

Le document fait la synthèse d'une enquête réalisée par le CLEO pour le Centre pour l'Egalité des chances entre 2010 et 2012. Il analyse la perception des discrimination par les enseignants, leur gravité ... [more ▼]

Le document fait la synthèse d'une enquête réalisée par le CLEO pour le Centre pour l'Egalité des chances entre 2010 et 2012. Il analyse la perception des discrimination par les enseignants, leur gravité, leurs évolutions. La synthèse montre que la discrimination liée au fonctionnement même du système scolaire sert de "toile de fond" à toutes les autres [less ▲]

Detailed reference viewed: 134 (11 ULiège)
See detailLes discriminations et la désaffiliation des jeunes issus de l’immigration
Perrin, Nathalie ULiege

Conference given outside the academic context (2014)

Detailed reference viewed: 14 (0 ULiège)
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See detailDiscriminative stimulus effects of ethanol with a conditioned taste aversion procedure: lack of acetaldehyde substitution
Quertemont, Etienne ULiege

in Behavioural Pharmacology (2003), 14(4), 343-350

Acetaldehyde has been suggested to mediate a number of the pharmacological and behavioural effects of ethanol. Recently, several studies investigated the role of acetaldehyde in the subjective effects of ... [more ▼]

Acetaldehyde has been suggested to mediate a number of the pharmacological and behavioural effects of ethanol. Recently, several studies investigated the role of acetaldehyde in the subjective effects of ethanol, but obtained conflicting results. With the discriminative taste aversion (DTA) procedure, high acetaldehyde doses were shown to substitute for the discriminative stimulus effects of ethanol. In contrast, the operant drug discrimination protocol failed to show any substitution effect of acetaldehyde. Several methodological differences between the two procedures could explain these discrepancies, and particularly the absence of an individual discrimination criterion in the DTA procedure. In the present study, the DTA procedure was adapted to introduce such a criterion. In addition, the effects of acetaldehyde were compared with those of other drugs, for which the substitution effects for ethanol are well known. Rats were trained to discriminate 1.0 g/kg ethanol from saline in a DTA protocol. When the rats met the criterion of ethanol discrimination, various doses of several drugs were tested for their ethanol stimulus substitution effects: ethanol, acetaldehyde, dizocilpine, diazepam and nicotine. The results showed a clear dose-dependent discrimination of ethanol stimulus effects. In addition, dizocilpine fully substituted for ethanol, while diazepam only partially substituted. In contrast, both acetaldehyde and nicotine failed to substitute for ethanol. These results show that acetaldehyde is not significantly involved in the subjective and discriminative stimulus effects of ethanol. Acetaldehyde up to toxic doses did not substitute for the ethanol discriminative stimulus in the DTA protocol, when non-specific effects were carefully controlled. [less ▲]

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See detailDiscriminative stimulus effects of ethanol: Lack of interaction with taurine
Quertemont, Etienne ULiege; Grant, Kathleen A.

in Behavioural Pharmacology (2004), 15(7), 495-501

Recent microdialysis studies showed that ethanol administration increases the release of taurine in various rat brain regions, and it was suggested that this increase in extracellular concentrations of ... [more ▼]

Recent microdialysis studies showed that ethanol administration increases the release of taurine in various rat brain regions, and it was suggested that this increase in extracellular concentrations of taurine might mediate some of the neurochemical effects of ethanol. Previous drug discrimination studies showed that positive modulators of the GABA(A) receptor consistently substituted for ethanol discriminative stimulus effects. Since taurine is also believed to modulate GABA(A) receptor activity, this study addressed the hypothesis that taurine mediates the discriminative stimulus effects of ethanol due to GABA(A) activation. Male Long-Evans rats were trained to discriminate water from either 1 or 2 g/kg ethanol. In a first experiment, various taurine doses (0-500 mg/kg) were tested to investigate whether taurine substitutes for ethanol. In a second experiment, rats were pretreated with either 500 mg/kg taurine or an equivalent volume of saline before testing for ethanol discrimination with various ethanol doses (0-2.0 g/kg). The results showed that taurine does not substitute for ethanol at any tested doses. In addition, taurine pretreatments failed to modify the dose-response curve for ethanol discrimination. These results demonstrate that taurine is not directly involved in mediating the discriminative stimulus effects of ethanol. It is therefore very unlikely that the brain release of taurine observed after ethanol administration is implicated in the major pharmacological effects of ethanol, i.e. positive modulation of GABA(A) receptor, that mediate its discriminative stimulus effects. [less ▲]

Detailed reference viewed: 20 (0 ULiège)
See detailDiscussant
Martiniello, Marco ULiege

Scientific conference (2015)

Detailed reference viewed: 17 (0 ULiège)
See detailDiscussant
Martiniello, Marco ULiege

Scientific conference (2009, January 28)

Detailed reference viewed: 6 (0 ULiège)
See detailDiscussant and Reporter at the Colloquium: “Multiculturalism, Minorities and Citizenship”
Martiniello, Marco ULiege

Scientific conference (1997, April 18)

Detailed reference viewed: 17 (0 ULiège)
See detailDiscussant de la session « Conceptual and methodological basis of the Concordia Discors project »
Martiniello, Marco ULiege

Scientific conference (2012, October 17)

Detailed reference viewed: 6 (0 ULiège)
See detailDiscussant in the Colloquium: “Rethinking Ethnic and Racial Studies”
Martiniello, Marco ULiege

Scientific conference (1997, May 16)

Detailed reference viewed: 3 (0 ULiège)