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See detailDo root-emitted volatile organic compounds interact with wireworms?
Barsics, Fanny ULg; Gfeller, Aurélie ULg; Laloux, Morgan ULg et al

Scientific conference (2012, May 22)

Wireworms are the soil dwelling larvae of click beetles (Coleoptera: Elateridae). Their importance as crop pests increases since the efficient chemical means to control them cannot be considered anymore ... [more ▼]

Wireworms are the soil dwelling larvae of click beetles (Coleoptera: Elateridae). Their importance as crop pests increases since the efficient chemical means to control them cannot be considered anymore. Therefore, many integrated pest management strategies have been investigated in the past few years. Most of them rely on the understanding of the ecology of the click beetles during their whole life cycle. We focus our work on the chemical ecology of wireworms, more precisely on the root-emitted volatile organic compounds (VOCs) that might intervene in the food-searching process of the larvae by helping them to find a suitable host-plant or by acting as key factors in the belowground defence mechanism of the plant. Here, we present our first results of dual-choice orientation tests in olfactometric pipes. Wireworms (Agriotes sordidus Illiger) were submitted individually to a variety of olfactory baits ranging from entire barley roots (Hordeum vulgare L. var. Quench) to isolated VOCs identified as part of the emitting profile. The latter was described thanks to HS-SPME samplings and GC-MS analysis, for roots grown in the exact same conditions as for the olfactometric experimentations with entire roots. Most of the experimentations gave significant results. When confronted to volatiles emitted by entire roots, wireworms significantly orientated towards the bait (χ²-goodness-of-fit test, χ²=8, P-value=0.005). This result allowed us to follow up with the same device and to progressively vary the nature of the baits. Our protocol should be used for other plant-wireworm species combinations. Our results should be taken into account in varietal selection, in crop rotation, or in trapping systems aiming at the reduction of the populations of wireworms. [less ▲]

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See detailDo Sex Differences in the Brain Explain Sex Differences in the Hormonal Induction of Reproductive Behavior? What 25 Years of Research on the Japanese Quail Tells Us
Balthazart, Jacques ULg; Tlemcani, O.; Ball, G. F.

in Hormones & Behavior (1996), 30(4), 627-61

Early workers interested in the mechanisms mediating sex differences in morphology and behavior assumed that differences in behavior that are commonly observed between males and females result from the ... [more ▼]

Early workers interested in the mechanisms mediating sex differences in morphology and behavior assumed that differences in behavior that are commonly observed between males and females result from the sex specificity of androgens and estrogens. [less ▲]

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See detailDo single, double or triple fungicide sprays differentially affect the grain quality in winter wheat?
El Jarroudi, Moussa ULg; kOUADIO, Louis; Junk et al

in Field Crops Research (2015), 183(257-266),

Foliar fungicides in wheat are typically used to safeguard against economic losses from diseases. In this study, we assessed the effects of three fungicide spray regimes [single, double, and triple ... [more ▼]

Foliar fungicides in wheat are typically used to safeguard against economic losses from diseases. In this study, we assessed the effects of three fungicide spray regimes [single, double, and triple treatments] on four different grain quality parameters [thousand grain weight (TGW), test weight (TW), grain protein content (GPC), and Zeleny sedimentation volume (ZSV)] during the 2006–2009 period at two sites in Luxembourg. The fungicides used were generally a mix of chlorothalonil and triazoles. At Burmerange, (cultivar Cubus), the values of TGW, TW, GPC and ZSV ranged from 38 to 62 g, 67 to 83 kg hl−1, 12.0% to 14.7% dry matter (DM), and 27 to 54 ml, respectively. Whereas, at Everlange (cultivar Achat), the ranges of TGW, TW, GPC and ZSV were 42 to 65 g, 65 to 81 kg hl−1, 11.0% to 15.0% DM, and 21 to 66 ml, respectively. In more than 75% cases, the results indicate that fungicides did not significantly affect TW or ZSV at either sites (P > 0.05). However, there was a significant and positive fungicide effect on GPC in 2006 and 2009 at Burmerange, and only in 2006 at Everlange (P < 0.05). On the contrary, TGW was significantly affected at Burmerange in all years, except 2008 when a positive increase was observed compared to control plots; and in 2006 and 2007 at Everlange. Interestingly, when there was an effect of fungicides on a quality parameter, there was no difference among different fungicide treatments. Thus under conditions prevailing in Luxembourg, a single fungicide treatment applied with judicious timing generally resulted in statistically similar grain quality parameters when compared with a double or triple fungicide treatment. [less ▲]

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See detailDo Spermathecal Morphology And Inter-Mating Interval Influence Paternity In The Polyandrous Beetle Tribolium Castaneum?
Bernasconi, Giorgina; Brostaux, Yves ULg; Meyer, Eric P. et al

in Behaviour (2006), 143(5), 643-658

In polyandrous insects, postcopulatory sexual selection is a pervasive evolutionary force favouring male and female traits that allow control of offspring paternity. Males may influence paternity through ... [more ▼]

In polyandrous insects, postcopulatory sexual selection is a pervasive evolutionary force favouring male and female traits that allow control of offspring paternity. Males may influence paternity through adaptations for sperm competition, and females through adaptations facilitating cryptic female choice. Yet, the mechanisms are often complex, involving behaviour, physiology or morphology, and they are difficult to identify. In red flour beetles (Tribolium castaneum), paternity varies widely, and evidence suggests that both male and female traits influence the outcome of sperm competition. To test the role of spermathecal morphology and of sperm storage processes on the outcome of sperm competition, we mated each of 26 virgin females with two males, one of which carrying a phenotypic marker to assign offspring paternity. We manipulated the interval between mating with the first and the second male, to create different conditions of sperm storage (overlapping and non-overlapping) in the female reproductive tract. To investigate the role of sperm storage more closely, we examined the relationship between paternity and spermathecal morphology in a subset of 14 experimental females. In addition, we also characterized variation in spermathecal morphology in three different strains, wildtype, Chicago black and Reindeer. No significant influence of the intermating interval was found on the paternity of the focal male, although the direction of the difference was in the expected direction of higher last male paternity for longer intervals. Moreover, paternity was not significantly associated with spermathecal morphology, although spermathecal volume, complexity, and tubule width varied significantly and substantially among individuals in all investigated strains. [less ▲]

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See detailDo spiders capture attention in a bottom-up fashion and does fear have an impact?
Devue, Christel ULg; Belopolsky, Artem; Theeuwes, Jan

Conference (2009)

Fear-related stimuli (e.g. spiders) seem to be prioritized during visual selection when they are actively searched for. This is especially true if the observers fear them. It remains unclear whether such ... [more ▼]

Fear-related stimuli (e.g. spiders) seem to be prioritized during visual selection when they are actively searched for. This is especially true if the observers fear them. It remains unclear whether such stimuli capture attention automatically when they are task-irrelevant. To answer that question, we used the additional singleton paradigm (Theeuwes, 1992) in which participants searched for a shape singleton (a circle among diamonds) while a fear-related stimulus (a spider) or a fear-unrelated stimulus (a butterfly) was also present in the display. To assess whether fear affects the extent of a possible bottom-up capture, we compared performance of participants that scored high or low on the Fear of Spiders Questionnaire (Szymanski & O'Donohue, 1995). Results showed that both types of task-irrelevant animals captured covert attention. Importantly, both types of animals produced larger interference in high-fear than in low-fear participants. This study suggests that fear as an individual characteristic influences bottom-up capture. [less ▲]

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See detailDo T2-hypointense GH-secreting pituitary adenomas behave differently under somatostatin analogues as primary therapy in acromegaly ?
Potorac, Iulia ULg; PETROSSIANS, Patrick ULg; Daly, Adrian ULg et al

in The International Journal of The Romania Society of Endocrinology - Abstract book (2015, June)

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See detailDo teachers speak too much?
Remacle, Angélique ULg

Scientific conference (2016, October 21)

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See detailDo Temperature Variations at the Surface of a Hot Non-Radial Pulsator Change Significantly the Line-Profile Variations?
De Ridder, J.; Aerts, C.; Dupret, Marc-Antoine ULg et al

in IAU Colloq. 185: Radial and Nonradial Pulsationsn as Probes of Stellar Physics (2002)

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See detailDo the counting methods distort our perception of bivalve diversity through time?
Ros-Franch, Sonia; Cascales - Miñana, Borja ULg; Martínez-Pérez, Carlos

Poster (2014, September)

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See detailDo the elderly feel older after exposure to negative aging stereotypes?
Marquet, Manon ULg; Missotten, Pierre ULg; Adam, Stéphane ULg

in International Psychogeriatrics (2016), 27(Supplement 1), 70-172

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See detailDo the properties of an $S$-adic representation determine factor complexity?
Durand, Fabien; Leroy, Julien ULg; Richomme, Gwenaël

in Journal of Integer Sequences (2013), 16(2), 132630

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See detailDo thiazolidinediones increase the risk of congestive heart failure and cardiovascular death?
Scheen, André ULg

in Nature Clinical Practice Endocrinology and Metabolism (2008), 4(5), 260-1

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See detailDo tonsilar FDCs express PrPc in sheep?
Toppets, Vinciane ULg; Piret,J; Minne,M et al

Poster (2007, October)

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See detailDo transnational practices damage the integration of migrants and their offspring ?
Martiniello, Marco ULg

Scientific conference (2011, February 23)

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See detailDo tree species influence community structure and richness of Ammonia Oxidizing Bacteria at three temperate forest sites?
Malchair, Sandrine ULg; Carnol, Monique ULg

Poster (2014, July 15)

Introduction: The relationship between biodiversity and ecosystem function remains a controversial subject with numerous open questions. In Europe, the conversion of coniferous monocultures into ... [more ▼]

Introduction: The relationship between biodiversity and ecosystem function remains a controversial subject with numerous open questions. In Europe, the conversion of coniferous monocultures into broadleaved or mixed stand is considered to face ecological and economical risks posed by coniferous monocultures. Belowground effects of such a change in the dominant tree species is however largely unknown, although bacteria regulate many soil processes and some groups, like ammonia oxidizing bacteria (AOB) are highly sensitive to environmental stress. Objectives: The aims of this study were to investigate (i) AOB community structure and richness under several tree species, (ii) microbial/environmental factors related to AOB diversity, (iii) the relationship between AOB diversity and the nitrification process. Materials and methods: Forest floor (Of, Oh) was sampled under European beech, sessile oak, Norway spruce and Douglas fir at three sites. AOB community structure and richness was assessed by PCR-DGGE and sequencing. Samples were analysed for net N mineralization, potential nitrification, basal respiration, microbial biomass, microbial or metabolic quotient, pH, total nitrogen, extractable ammonium, organic matter content and exchangeable cations. Results: AOB community structure and tree species effects on AOB diversity were site-specific. Factors regulating ammonium availability, i.e. net N mineralization or microbial biomass, were related to AOB community structure. AOB richness was not related to nitrification. Conclusions: Our research revealed that, at larger spatial scales, site specific characteristics may be more important that tree species in determining AOB richness and community structure. Within sites, tree species influence AOB diversity. The absence of a relation between AOB richness and nitrification points to a possibly role of AOB abundance, phenotypic plasticity or the implication of ammonia oxidizing archaea in this process. [less ▲]

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See detailDo Triclosan affect hearing development of Cyprinodon variegatus larvae?
Schnitzler, Joseph ULg; Benichou, Farida; Pinte, Nicolas et al

Poster (2015, August)

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Larval stages are ... [more ▼]

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Larval stages are particularly vulnerable to deleterious effects of endocrine disrupters because of potential impairment of fish development and behaviour. Thyroid hormones are critical to the development of the brain and auditory system. Thus, TCS could affect the development of the brain and hearing. The aims of this study were: to investigate hearing development in sheepshead minnows (Cyprinodon variegatus) using the ABR technique (Auditory Brainstem Response) and to investigate the effects of triclosan on hearing development. Exposure to TCS was conducted from fertilization of eggs on at concentrations likely to be found in the environment: 20, 50 and 100 µgl-1. We characterized previously the ontogenic variation of thyroid hormones in embryos and larvae of sheepshead minnows. We observed an increase of thyroid hormones level around the 12th and the 15th day post hatching (dph), that may be associated with the transition from larval to juvenile stage during the development of this species. We concluded, that this period could be defined as a critical exposure window to pollutants. We determined hearing thresholds for sheepshead minnows of different ages. Our sheepshead minnows show ontogenic variations in the hearing ability during their development. At 30 days post hatching, their hearing ability is quite bad, with a narrow bandwidth of detected frequencies. But their hearing ability considerably enhance during their development to reach the adult hearing ability at around 80 days post hatching when this species reach sexual maturity. So we observe during the developmental phase of this fish species clear ontogenic improvements of the hearing ability and they showed an ontogenetic expansion in the frequency bandwidth they were able to detect. The effects of TCS in this development have yet to be determined but will be fully discussed. This study proposes an interesting new endpoint in thyroid disruption research. [less ▲]

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See detailDo utility values and willingness to pay suitably reflect health outcome in hip and knee osteoarthritis? A comparative analysis with the WOMAC index
Ethgen, Olivier ULg; Tancredi, Annalisa ULg; Lejeune, Emmanuelle ULg et al

in Journal of Rheumatology (2003), 30(11), 2452-2459

Objective. To establish whether health utility (time trade-off, TTO) and willingness to pay (WTP) values reflect clinical health outcome as evaluated by the Western Ontario McMaster Universities ... [more ▼]

Objective. To establish whether health utility (time trade-off, TTO) and willingness to pay (WTP) values reflect clinical health outcome as evaluated by the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) in hip and knee osteoarthritis (OA). Methods. One hundred twenty-eight patients with OA attending a specialized arthritis clinic were interviewed about their socioeconomic characteristics and administered the TTO technique and the WOMAC. Their WTP for 2 hypothetical anti-osteoarthritic drugs was also investigated: the first drug was said to provide a significant improvement in WOMAC dimensions and the second a complete cure of the disease. WTP was elicited by both discrete-choice and bidding game methods. Results. Answer rates were 89.1% for TTO, 98.4% for discrete-choice WTP for both scenarios, and 89.8% and 85.2% for bidding game WTP in the relief and the cure scenario, respectively. The mean TTO utility value was 0.84 (standard deviation 0.20). In discrete-choice, those accepting the bid had higher monthly income (euro 1536.5 vs euro 1060. 1, p < 0.001, for the relief scenario and euro 1449.3 vs euro 1071.6, p < 0.001, for the cure scenario). With the bidding game format, WTP was positively correlated with income in both scenarios (r = 0.56, r = 0.55, p < 0.001). WTP measures differed equally between education and socioeconomic groups with those in favored groups consistently reporting higher WTP (Kruskal-Wallis tests statistics ranging from p < 0.01 to p < 0.001). Except for stiffness, WOMAC dimensions were correlated in the expected direction with TTO values (r = -0.27, p < 0.01 for pain and r = -0.36, r = -0.34, p < 0.001 for physical function and total score, respectively). Conclusion. Whereas they showed good feasibility, WTP measures poorly reflected clinical condition and were mainly related to economic status and ability to pay. TTO was correlated with the WOMAC dimensions and may be considered closer to clinical situations than WTP. However, concern arises regarding the homogeneity of the study sample in terms of clinical severity, which may have precluded the identification of a relationship between WTP and clinical status. [less ▲]

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See detailDo we have enough pieces of the jigsaw to integrate CO2 fluxes in the Coastal Ocean ?
Borges, Alberto ULg

in Estuaries (2005), 28(1), 3-27

Annually integrated air-water CO2 flux data in 44 coastal environments were compiled from literature. Data were gathered in 8 major ecosystems (inner estuaries, outer estuaries, whole estuarine systems ... [more ▼]

Annually integrated air-water CO2 flux data in 44 coastal environments were compiled from literature. Data were gathered in 8 major ecosystems (inner estuaries, outer estuaries, whole estuarine systems, mangroves, salt marshes, coral reefs, upwelling systems, and open continental shelves), and up-scaled in the first attempt to integrate air-water CO2 fluxes over the coastal ocean (26 3 106 km2), taking into account its geographical and ecological diversity. Air-water CO2 fluxes were then up-scaled in global ocean (362 3 106 km2) using the present estimates for the coastal ocean and those from Takahashi et al. (2002) for the open ocean (336 3 106 km2). If estuaries and salt marshes are not taken into consideration in the up-scaling, the coastal ocean behaves as a sink for atmospheric CO2 (21.17 mol C m22 yr21) and the uptake of atmospheric CO2 by the global ocean increases by 24% (21.93 versus 21.56 Pg C yr21). The inclusion of the coastal ocean increases the estimates of CO2 uptake by the global ocean by 57% for high latitude areas (20.44 versus 20.28 Pg C yr21) and by 15% for temperate latitude areas (22.36 versus 22.06 Pg C yr21). At subtropical and tropical latitudes, the contribution from the coastal ocean increases the CO2 emission to the atmosphere from the global ocean by 13% (0.87 versus 0.77 Pg C yr21). If estuaries and salt marshes are taken into consideration in the upscaling, the coastal ocean behaves as a source for atmospheric CO2 (0.38 mol C m22 yr21) and the uptake of atmospheric CO2 from the global ocean decreases by 12% (21.44 versus 21.56 Pg C yr21). At high and subtropical and tropical latitudes, the coastal ocean behaves as a source for atmospheric CO2 but at temperate latitudes, it still behaves as a moderate CO2 sink. A rigorous up-scaling of air-water CO2 fluxes in the coastal ocean is hampered by the poorly constrained estimate of the surface area of inner estuaries. The present estimates clearly indicate the significance of this biogeochemically, highly active region of the biosphere in the global CO2 cycle. [less ▲]

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