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See detailEffects of wheat-pea intercropping on the population dynamics of Sitobion avenae (Homoptera: Aphididae) and its main natural enemies
Zhou, Haibo ULiege

in Kun Chong Xue Bao = Acta Entomologica Sinica (2009), 52(7), 775-782

To study the ecological regulation effects of species diversity in wheat fields on Sitobion avenae, field experiments were carried out in Langfang Experimental Station of Institute of Plant Protection ... [more ▼]

To study the ecological regulation effects of species diversity in wheat fields on Sitobion avenae, field experiments were carried out in Langfang Experimental Station of Institute of Plant Protection, Chinese Academy of Agricultural Sciences from October of 2007 to July of 2008. The intercropping patterns of wheat and pea, by the proportion of planting row of pea and wheat in 2:2, 2:4, 2:6 and 2:8, were plotted, and the field cultivar monoculture of wheat was planted as the control. Population dynamics of apterae and alatae S. avenae, population dynamics, species richness, diversity index and evenness of main natural enemies were investigated systematically and analyzed. The results showed that, compared with monoculture of wheat, the amount of S. avenae apterae per 100 plants (square-root transformed) in aphid peak period were very significantly lower in the intercropping treatments (P<0.01), and the cascade was that wheat monoculture (77.38) > 2-2 intercropping (68.62) > 2-4 intercropping (68.51) > 2-8 intercropping (65.19) > 2-6 intercropping (64.94). Although population dynamics of main natural enemies showed a similar trend with time, wheat-pea intercropping could preserve and augment natural enemies more than monoculture of wheat, and there were higher population densities of ladybeetles and aphid parasitoids, and higher species richness and diversity index of natural enemies, but lower evenness index in each intercropping field. It is so concluded that wheat-pea intercropping system can not only reduce the population of S. avenae, but also improve the stability and sustainability of controlling wheat pests. [less ▲]

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See detailEffects of wheat/oilseed rape and wheat/pea associations on the diversity of aphids and aphidophagous beneficials
Chevalier Mendes Lopes, Thomas ULiege; Bosquée, Emilie ULiege; Honba, David et al

Poster (2014, May 20)

This study was conducted in the Shandong province (China) to better characterize the effect of wheat/oilseed rape and wheat/pea associations on the populations of aphids and aphidophagous beneficials. At ... [more ▼]

This study was conducted in the Shandong province (China) to better characterize the effect of wheat/oilseed rape and wheat/pea associations on the populations of aphids and aphidophagous beneficials. At specific times of the season, the observations on wheat tillers confirm the resource concentration and the enemy hypotheses. In fact, aphids were more abundant in the pure stand of wheat, while more ladybirds were observed in the associations. As for the trapping of aphidophagous beneficials, the parasitoid species Aphidius gifuensis (Ashmead) was prevalent. Among predators, Propylea japonica (Thunberg) and Harmonia axyridis (Pallas) were the most abundant species. Few lacewings and hoverflies were trapped. This study shows a beneficial effect of crop associations on the control of aphid populations. [less ▲]

Detailed reference viewed: 41 (14 ULiège)
See detailEffects of Whole body Vibration in the elderly
Bruyère, Olivier ULiege

Conference (2004, May 15)

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See detailEffects of widespread fish introductions on paedomorphic newts in Europe
Denoël, Mathieu ULiege; Džukić, Georg; Kalezic, Milos L.

in Conservation Biology (2005), 19(1), 162-170

As a result of factors such as global warming, habitat destruction, and species introduction, amphibians are declining worldwide. No one, however, has analyzed the status of polymorphic amphibian species ... [more ▼]

As a result of factors such as global warming, habitat destruction, and species introduction, amphibians are declining worldwide. No one, however, has analyzed the status of polymorphic amphibian species at a national or continental scale, although some local reports exist. Our aim was to report on the loss of intraspecific heterochrony as a loss to diversity in determining the consequences of fish stocking on European populations of paedomorphic newts. Paedomorphosis is a polymorphism in which larval traits are retained in the adult stage. We surveyed 39 paedomorphic populations of the alpine ( Triturus alpestris) and palmate ( T. helveticus) newts, all but one of which initially occupied fishless ponds and lakes in France, Italy, Slovenia, Bosnia, Montenegro, and Greece. Exotic fishes were found in 44% of the studied aquatic habitats, with a 100% presence in Montenegro. At all sites paedomorphs disappeared and metamorphs declined. Only fish explained these population changes because alternative factors such as drying were not significant. More catastrophically, fish introductions occurred in habitats known to support the largest populations of newts and even some endemic subspecies. If management and legislative measures are not taken to stop fish stocking, protect paedomorphs as conservation units at national and international levels, and restore natural habitats, all the largest paedomorphic populations may disappear in the near future. Their disappearance would represent a loss of one of the rare, fascinating examples of intraspecific heterochrony. [less ▲]

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See detailEffects of wildflower strips and an adjacent forest on aphids and their natural enemies in a pea field
Hatt, Séverin ULiege; Mouchon, Pierre; Chevalier Mendes Lopes, Thomas ULiege et al

in Insects (2017), 8(3), 99

Landscape diversification is a key element for the development of sustainable agriculture. This study explores whether the implementation of habitats for pest natural enemies enhances conservation ... [more ▼]

Landscape diversification is a key element for the development of sustainable agriculture. This study explores whether the implementation of habitats for pest natural enemies enhances conservation biological control in an adjacent field. In the present study conducted in Gembloux (Belgium) in 2016, the effect of two different habitats (wildflower strips and a forest) and aphid abundance on the density of aphid natural enemies, mummified aphids and parasitism on pea plants was assessed through visual observations. The effect of the habitats on aphids was also evaluated. The habitats but not aphid density significantly affected hoverfly larvae, which were more abundant adjacent to wildflower strips than to the forest. The contrary was observed for ladybeetle adults, which were positively related with aphids but not affected by the adjacent habitats. The abundance of mummies and the parasitism rate were significantly affected by both the habitats and aphid density. They were both significantly enhanced adjacent to wildflower strips compared to the forest, but the total parasitism rate was low (<1%), questioning whether parasitoids could significantly control aphids on the pea crop. As for the aphids, their abundance was not significantly affected by the adjacent habitats. These results are discussed with respect to the potential of these habitats to provide overwintering sites and food resources for natural enemies, and thereby enhance conservation biological control. [less ▲]

Detailed reference viewed: 23 (1 ULiège)
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See detailEffects of word-evoked object size on covert numerosity estimations.
Dumitru, Magdalena ULiege; Joergensen, Gitte H.

in Frontiers in Psychology (2015), 6

We investigated whether the size and number of objects mentioned in digit-word expressions influenced participants’ performance in covert numerosity estimations (i.e., property probability ratings ... [more ▼]

We investigated whether the size and number of objects mentioned in digit-word expressions influenced participants’ performance in covert numerosity estimations (i.e., property probability ratings). Participants read descriptions of big or small animals standing in short, medium, and long rows (e.g., There are 8 elephants/ants in a row) and subsequently estimated the probability that a health statement about them was true (e.g., All elephants/ants are healthy). Statements about large animals scored lower than statements about small animals, confirming classical findings that humans perceive groups of large objects as being more numerous than groups of small objects (Binet, 1890) and suggesting that object size effects in covert numerosity estimations are particularly robust. Also, statements about longer rows scored lower than statements about shorter rows (cf. Sears, 1983) but no interaction between factors obtained, suggesting that quantity information is not fully retrieved in digit—word expressions or that their values are processed separately. [less ▲]

Detailed reference viewed: 13 (2 ULiège)
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See detailThe Effects of Workers’ Participation on Enterprise Performance: Empirical Evidence from French Producer Co-operatives
Defourny, Jacques ULiege; Estrin, Saul; Jones, Derek C.

in International Journal of Industrial Organization (1985), 3(2), 197-218

The results of estimating production functions augmented by various measures of workers' participation on a large enterprise level data set of French cooperatives are reported. Value added is found to be ... [more ▼]

The results of estimating production functions augmented by various measures of workers' participation on a large enterprise level data set of French cooperatives are reported. Value added is found to be an increasing function of participation in profits, in collective membership and in ownership, even when a wide assortment of enterprise specific and environmental factors are taken into account. This finding is very robust, surviving tests between alternative specifications of technology, for reverse causality, for simultaneous equation bias and for multicollinearity. The typical productivity effect from participation, however, is small, around 5% of output. The results suggest that Western policymakers should investigate ways to increase workers' participation in capital stakes and profit shares. [less ▲]

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See detailThe effects of xylo-oligosaccharides on performance and microbiota in broiler chickens.
De Maesschalck, C.; Eeckhaut, V.; Maertens, L. et al

in Applied and environmental microbiology (2015)

In broiler chickens, feed additives, including prebiotics, are widely used to improve gut health and to stimulate performance. Xylo-oligosaccharides (XOS) are hydrolytic degradation products of ... [more ▼]

In broiler chickens, feed additives, including prebiotics, are widely used to improve gut health and to stimulate performance. Xylo-oligosaccharides (XOS) are hydrolytic degradation products of arabinoxylans that can be fermented by the gut microbiota. In the current study it was aimed to analyze the prebiotic properties of XOS when added to the broiler diet. Administration of XOS to chickens, on top of a wheat/rye-based diet, significantly improved the feed conversion ratio. XOS significantly increased villus length in the ileum. It also significantly increased numbers of lactobacilli in the colon and Clostridium cluster XIVa in the caeca. Moreover, the number of gene copies encoding the key bacterial enzyme for butyrate production, butyryl-CoA:acetate CoA-transferase, was significantly increased in the caeca of chickens administered XOS. In this group of chickens, at species level, Lactobacillus crispatus and Anaerostipes butyraticus were significantly increased in abundance in the colon and caecum, respectively. In vitro fermentation of XOS revealed cross-feeding between L. crispatus and A. butyraticus. Lactate, produced by L. crispatus during XOS fermentation, was utilized by the butyrate-producing Anaerostipes species. These data show the beneficial effects of XOS on broiler performance when added to the feed, which potentially can be explained by stimulation of butyrate-producing bacteria through cross-feeding of lactate and subsequent effects of butyrate on gastrointestinal function. [less ▲]

Detailed reference viewed: 202 (8 ULiège)
See detailEffects of α-Hederin on cells cultured in vitro
Quetin-Leclercq, Joelle; Danloy, Sophie; Coucke, Paul et al

Poster (1993, June)

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See detailEffects of α-synuclein levels on cerebral synaptic function: Validation of a novel PET radioligand for the early diagnosis of Parkinson’s disease
Tarragon Cros, Ernesto ULiege; Ferrara, André ULiege; Tirelli, Ezio ULiege et al

Poster (2015, January 27)

Background In Parkinson’s disease, converging evidence supports a pathogenic role for excessive α–synuclein accumulation in synaptic terminals that may propagate back to the soma of vulnerable nerve cells ... [more ▼]

Background In Parkinson’s disease, converging evidence supports a pathogenic role for excessive α–synuclein accumulation in synaptic terminals that may propagate back to the soma of vulnerable nerve cells such as neurons in the substantia nigra pars compacta. The resulting loss of dopaminergic terminals in the striatum can be demonstrated in vivo using 18F-Dopa-PET (positron emission tomography). However, there’s currently no validated biomarker of the progressive synaptic dysfunction in other vulnerable areas such as the cerebral cortex. Goal In this longitudinal study, we will test the hypothesis that the loss of synaptic terminals in a mouse model of excessive α–synuclein accumulation can be demonstrated in vivo before the occurrence of behavioural disturbances using 18F-UCB-H, a new PET biomarker developed at CRC. We will also test if this new imaging modality is sensitive enough to study the effect of a disease modifying therapy such as chronic physical exercise. Methods We will use microPET for the in vivo quantification of 18F-UCB-H brain uptake in 16 wild type animals and 16 transgenic (Tg) mice overexpressing human α–syn under the mThy1 promotor every 2 months. Data will be validated against post-mortem analyses after the last PET study. Predictions We predict decreased tracer uptake over time in the basal ganglia and cerebral cortex in Tg mice as compared with WT animals. Also, we predict a relationship between 18F-UCB-H uptake levels in basal ganglia and cerebral cortex and progressive alterations in both motor and cognitive functions, respectively. Further, we also expect that chronic exercise will slow down both motor and cognitive disturbances, as well as the rate of 18F-UCB-H brain uptake decreases. Conclusion If 18F-UCB-H PET proves to be a valid biomarker for the early detection of α–synuclein accumulation in the pre-clinical model of PD, the methods will tested on human clinical populations. [less ▲]

Detailed reference viewed: 237 (28 ULiège)
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See detailEffects on animal performance of a supplement to suckling grazing calves
Dufrasne, Isabelle ULiege; Istasse, Louis ULiege; Limbourg, Pierre et al

in Proceedings of the 43th Annual Meeting of E.A.A.P. (1992)

Detailed reference viewed: 11 (2 ULiège)
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See detailEffects on cellular invasion of 6-(acetoxymethyl)-2-oxo-2H-1-benzopyran-3-carboxylic acid derivatives
Kempen, I.; Pochet, L.; Papapostolu, D. et al

Poster (2001, April 21)

Detailed reference viewed: 6 (0 ULiège)
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See detailEffects on cellular invasion of two synthetic coumarins
Kempen, I.; Papapostolou, D.; Pochet, L. et al

Conference (2001, May)

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See detailEffects on in vitro and in vivo cellular invasion of two 6-(acetoxymethyl)-2-oxo-2H-1-benzopyran-3-carboxylic acid derivatives
Kempen, I.; Pochet, L.; Papapostolou, D. et al

Poster (2001, October 16)

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See detailEffects on nicotine administered via a transdermal delivery system on vigilance : a repeated measure study
Mancuso, Giovanna; Andrès Bénito, Pilar; Ansseau, Marc ULiege et al

in Psychopharmacology (1999), 142(1), 18-23

Tested 15 male smokers (aged 18-25 yrs) in a within-Ss design to determine the influence of a transdermal patch of 21 mg nicotine on vigilance. Ss were tested on the Rapid Visual Information Processing ... [more ▼]

Tested 15 male smokers (aged 18-25 yrs) in a within-Ss design to determine the influence of a transdermal patch of 21 mg nicotine on vigilance. Ss were tested on the Rapid Visual Information Processing test 1.3, 3 and 6.3 hrs after patch application, to verify the involvement of the dose of nicotine on the performance. The results confirm and extend the knowledge on the increasing effects of nicotine on vigilance previously found with orally and transdermally administered nicotine. Moreover, results show that such performance was independent of the time of nicotine absorption, which suggests that a relatively low dose of nicotine suffices to activate vigilance processing. Regarding motor performance, no convincing effect of nicotine was observed on reaction time. ((c) 1999 APA/PsycINFO, all rights reserved) [less ▲]

Detailed reference viewed: 41 (3 ULiège)
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See detailEffects on Pcbs on Liver Ultrastructure and Monooxygenase Activities in Japanese Quail
Stouvenakers, Nadine ULiege; Hugla, J. L.; Goffinet, Gerhard ULiege et al

in Bulletin of Environmental Contamination & Toxicology (1996), 56(5), 839-46

Detailed reference viewed: 15 (0 ULiège)