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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 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 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 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; Delille, Bruno ULg; Schoemann, V. et al

Poster (2004, October)

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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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See detailDo we need a new carotid artery stenting trial?
Van Damme, Hendrik ULg; Defraigne, Jean ULg

in Acta Chirurgica Belgica (2010), 110(4), 432-44

Four well-conducted carotid artery trials comparing carotid artery stenting with carotid artery endarterectomy (EVA-3S, SPACE, ICSS and CREST) could not demonstrate the superiority of carotid artery ... [more ▼]

Four well-conducted carotid artery trials comparing carotid artery stenting with carotid artery endarterectomy (EVA-3S, SPACE, ICSS and CREST) could not demonstrate the superiority of carotid artery stenting (CAS) over carotid artery endarterectomy (CEA). There is at the moment no level-I evidence to support widespread use of endovascular management of carotid artery disease in routine practice. In order to shead some light on the continuing debate on the role of carotid artery stenting, the authors conducted a search in contemporary published literature concerning carotid artery stenting. This extensive literature review reveals a higher peri-procedural stroke-death rate after CAS and a higher cost. Two other events hamper the value of CAS: a higher late restenosis rate and a higher risk of micro-embolisation during the procedure, compared with CEA. The authors conclude that the prevailing overenthusiasm of interventionalists (vascular surgeons, radiologists, cardiologists) for carotid artery stenting is not justified. [less ▲]

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See detailDo we need dark matter in cosmology?
Magain, Pierre ULg; Hauret, Clémentine ULg

Conference (2014, November 19)

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See detailDo we Need to Solve the Exozodi Question? If Yes, How to Best Solve It?
Absil, Olivier ULg; Eiroa, C.; Augereau, J. et al

in Coudé du Foresto, Vincent; Gelino, Dawn; Ribas, Ignasi (Eds.) Pathways Towards Habitable Planets (2010, October 01)

When observing an extrasolar planetary system, the most luminous component after the star itself is generally the light scattered and/or thermally emitted by a population of micron-sized dust grains ... [more ▼]

When observing an extrasolar planetary system, the most luminous component after the star itself is generally the light scattered and/or thermally emitted by a population of micron-sized dust grains. These grains are expected to be continuously replenished by the collisions and evaporation of larger bodies just as in our solar zodiacal cloud. Exozodiacal clouds (“exozodis”) must therefore be seriously taken into account when attempting to directly image faint Earth-like planets (exoEarths, for short). This paper summarizes the oral contributions and discussions that took place during the Satellite Meeting on exozodiacal dust disks, in an attempt to address the following two questions: Do we need to solve the exozodi question? If yes, how to best solve it? [less ▲]

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See detailDo we need to standardize extraction procedures for community level physiological profiling?
Carnol, Monique ULg; Bosman, Bernard ULg; Malchair, Sandrine ULg

Poster (2011, July)

Microorganisms are essential regulators of soil functioning, as they are involved in many crucial processes such as organic matter decomposition, nutrient cycling, soil structure and fertility. Currently ... [more ▼]

Microorganisms are essential regulators of soil functioning, as they are involved in many crucial processes such as organic matter decomposition, nutrient cycling, soil structure and fertility. Currently, there is a growing interest in functional diversity, such as the number and type of substrates used for energy metabolism (CLPP-community level physiological profiling). Such metabolic diversity of heterotroph soil bacteria is frequently investigated through Biolog Ecoplates, containing 31 of the most useful carbon sources for the soil community. The metabolic diversity of soil bacteria might be an interesting biological indicator of soil quality, and also a useful tool for investigating the link between land use change, climate warming, soil carbon, microbial diversity and activity. Methods related to Biolog-CLPP reported in the literature differ in the suspension medium and extraction method, the type and density of inoculums, the inoculation procedures and conditions of incubations. For example, various combinations of extraction methods and suspension media are being used for the first bacterial extraction step. Despite such methodological differences, Biolog-CLPP data are often compared across studies. The development of a standardised method for Biolog-CLPP is however essential improving the relevance and significance of results across studies. In this work, we investigated the influence of extraction procedures on microbial extraction efficiency for further use in CLPP. The microbial extraction efficiency was tested by plate counts for a total of twelve combinations of three suspension media and four extraction methods. The experiment was performed on four soils differing in organic matter content. The aims of this study were to: • Synthesize extraction procedures used for Biolog-CLPP • Measure the effect of extraction procedures on microbial extraction efficiency (plate counts) in four soil types • Investigate a possible interaction between the suspension media and the extraction method used • Evaluate whether a standardized extraction procedure can be recommended across soil types [less ▲]

Detailed reference viewed: 75 (10 ULg)