Are cannibalistic morphs of the tiger salamander obligatory cannibals?
Denoël, Mathieu ; ;
Tiger salamanders exhibit alternative trophic morphologies, with cannibals developing a larger head and longer teeth than typical larvae. Resource partitioning is known between morphs, with cannibal ... [more ▼]
Tiger salamanders exhibit alternative trophic morphologies, with cannibals developing a larger head and longer teeth than typical larvae. Resource partitioning is known between morphs, with cannibal morphs usually foraging on conspecifics and rarely on small organisms. Our aim was to determine whether the cannibal and typical morphs shift their diets across time and particularly whether conspecifics are necessarily the main prey of cannibals and plankton the primary prey of typicals. We found that only the cannibal morph foraged on conspecifics, but not all the time. Cannibalism typically occurred only early after the ontogenetic divergence between morphs. Cannibals shifted their diet later in the summer to plankton, and this ontogenetic shift led to dietary overlap with the typical morph. In contrast to other studies, our findings suggest that the cannibal morphology actually allows the consumption of a larger variety of prey, rather than specialization on specific resources (i.e., conspecifics). The outcomes of the cannibalistic ontogenetic pathway include a higher biomass intake from food and a larger size than typicals. From a foraging perspective, the cannibalism pathway is clearly advantageous over the typical morphology. However, the increased diet breadth of cannibal morphs found in this study suggests that the maintenance of the polyphenism is more complex than has previously been suggested. [less ▲]Detailed reference viewed: 44 (0 ULg)
ARE CAPABILITY INDICES USEFULL TO ASSESS ANALYTICAL METHODS VALIDITY ?
Rozet, Eric ; Bouabidi, Abderrahim ; et al
Poster (2012, February)
Analytical methods capability evaluation can be a useful methodology to assess the fitness of purpose of these methods for their future routine application. However, care on how to compute the capability ... [more ▼]
Analytical methods capability evaluation can be a useful methodology to assess the fitness of purpose of these methods for their future routine application. However, care on how to compute the capability indices has to be made. Indeed, the commonly used formulas to compute capability indices such as Cpk, will highly overestimate the true capability of the methods. Especially during methods validation or transfer, there are only few experiments performed and, using in these situations the commonly applied capability indices to declare a method as valid or as transferable to a receiving laboratory will conduct to inadequate decisions. In this work, an improved capability index, namely Cpk-tol and the corresponding estimator of proportion of non conforming results ( ) is proposed. Through Monte-Carlo simulations, they have been shown to greatly increase the estimation of analytical methods capability in particular in low sample size situations as encountered during methods validation or transfer. Additionally, the usefulness of this capability index is illustrated through several case studies covering applications commonly encountered in the pharmaceutical industry. Finally a methodology to determine the optimal sample size required to validate analytical methods is also given using the proposed capability metric. [less ▲]Detailed reference viewed: 95 (5 ULg)
Are cardiac markers useful in patients with chronic renal failure?
Conference (2001, May)Detailed reference viewed: 2 (0 ULg)
Are cardiac markers useful in patients with chronic renal failure?
in Clinical Chemistry & Laboratory Medicine (2001), 39(suppl), 36Detailed reference viewed: 4 (0 ULg)
Are central executive functions working in patients with focal frontal lesions?
; Van der Linden, Martial
in Neuropsychologia (2002), 40(7), 835-845
The aim of this study was to examine the hypothesis of a link between frontal cortex and two executive functions in working memory: the capacity to perform a dual task and the ability to inhibit ... [more ▼]
The aim of this study was to examine the hypothesis of a link between frontal cortex and two executive functions in working memory: the capacity to perform a dual task and the ability to inhibit irrelevant information. A dual task designed to assess the capacity to perform storage and processing simultaneously and a directed forgetting task designed to assess the capacity to actively inhibit no-longer relevant information were administered to a group of patients with focal frontal lesions and to a group of control participants. The results revealed that despite showing reduced short-term storage, frontal patients performed the dual task and inhibited the no-longer relevant information as well as control participants. These findings suggest that not all-executive processes are exclusively sustained by the frontal cortex [Quart J Exp Psychol 9 (1996) 5; Curr Opin Neurobiol 10 (2000) 195; Neuropsychology (1994) 544; The Cognitive Neuropsychology of Alzheimer-type dementia. Oxford, New York: Oxford University Press, 1996]. [less ▲]Detailed reference viewed: 7 (2 ULg)
Are Children Conservative, Liberal or Metacognitive? Preliminary Evidence for the Involvement of the Distinctiveness Heuristic in Decision Making
Geurten, Marie ; Willems, Sylvie ; Meulemans, Thierry
in Journal of Experimental Child Psychology (2015), 132
The present experiment investigates whether young children are able to reduce their false recognition rate after distinctive encoding by implementing a strategic metacognitive rule. Seventy-two children ... [more ▼]
The present experiment investigates whether young children are able to reduce their false recognition rate after distinctive encoding by implementing a strategic metacognitive rule. Seventy-two children, aged 4, 6, and 9 years, studied two lists of unrelated items. One of these lists was visually displayed (picture condition) while the other was presented auditorily (word condition). After each study phase, participants completed recognition tests. Finally, they answered questions about their explicit knowledge of the distinctive-encoding effect. The results revealed that even the youngest children in our sample showed a smaller proportion of intrusions in the picture condition than in the word condition. Furthermore, the results of the signal detection analyses were consistent with the hypothesis that the lower rate of false recognitions after picture encoding results from the implementation of a conservative response criterion based on metacognitive expectations (distinctiveness heuristic). Moreover, the absence of correlation between children’s explicit knowledge of the distinctiveness rule and their effective use of this metacognitive heuristic seems to indicate that its involvement in memory decisions could be mediated by implicit mechanisms. [less ▲]Detailed reference viewed: 36 (5 ULg)
Are Cities of Northern Europe at Risk ?
Plumier, André ;
in Proceedings of the Workshop Mitigation of Seismic Risk - Support to recently Affected European Countries (2000, November)
A benchmark study on seimic risk has been realised on Liege, Belgium, at the request of the Regional Authority. Its main interest is that it deals with the seismic risk of a city in a low seismicity ... [more ▼]
A benchmark study on seimic risk has been realised on Liege, Belgium, at the request of the Regional Authority. Its main interest is that it deals with the seismic risk of a city in a low seismicity region. The work involves a hazard study based on the recently defined map of seismicity of Belgium, the definition of the individual vulnerability of buildings, the combination of hazard and vulnerability to define risk and static evaluations of connecting details in non engineered structures. For the evaluation of vulnerability, a simplified screening method has been defined. The main conclusion is that in regions where the Peak Ground Acceleration is higher than 0,1g and the building stock does not possess good structural quality, the seismic risk may be considered high. [less ▲]Detailed reference viewed: 20 (0 ULg)
Are CNA42 and FDC-B1 directed against ovine follicular dendritic cells?
Toppets, Vinciane ; ; et al
Poster (2006, October)Detailed reference viewed: 9 (5 ULg)
Are COX-2 Inhibitors Active on Intracellular Oxidative Processes? A Study on In Vitro and Cellular Models
Mouithys-Mickalad, Ange ; ; et al
Book published by Nova Science Publishers, Inc. (2006)
In the last years, there has been an increasing interest of using cyclooxygenase-2 (COX-2) inhibitors to treat the inflammatory pain and chronic inflammatory diseases such as osteoarthritis and rheumatoid ... [more ▼]
In the last years, there has been an increasing interest of using cyclooxygenase-2 (COX-2) inhibitors to treat the inflammatory pain and chronic inflammatory diseases such as osteoarthritis and rheumatoid arthritis. The beneficial effects were to avoid the secondary adverse effects such as bleeding and gastric irritation, generally observed with aspirin and conventional NSAIDs. COX-1 is constitutively expressed in most tissues and involved in the regulation of normal homeostatic functions, while COX-2 is not detected in most tissues but induced by inflammatory stimuli. These outcomes motivated the commercial development of selective COX-2 inhibitors. Recent data suggested that the COX-2 enzyme can be expressed within atherosclerotic lesions and could play a crucial role in various types of cancers, by the way of its activity on the ROS production, gene transcription and prostaglandin (PGE2) production. Consequently, the COX-2 enzyme has become a real target for the study of various classes of compounds and specially the possible additional properties of COX-2 inhibitors. We and other groups have already investigated the pro or antioxidant profile of conventional NSAIDs and some COX-2 inhibitors. With the recent withdrawal of two compounds of the coxib’s family (rofecoxib and celecoxib), for adverse cardiovascular events, concerns regarding the safety of all COX-2 inhibitors have been raised. To answer to these concerns, different approaches were developed by studying on in vitro models, the potential inhibiting-or-stimulating activities on oxidative phenomena of new drugs with already recognized therapeutic effects. Preliminary data obtained with COX-2 inhibitors showed a moderate inhibiting effect on the intracellular oxidant processes and others a stimulating activity. New hypotheses for the treatment of inflammation are now suggested for compounds like nimesulide and its analogous, which are selective towards COX-2 with little activity on COX-1. Here, we reported the in vitro effects of some Cox-2 inhibitors, in comparison with traditional drugs (ibuprofen, diclofenac and aceclofenac) by using two cellular models: a human lung type II alveolar cell line (A549) and a human promonocyte cell line (THP-1). The direct interactions between the drugs and ROS were also investigated in cell-free systems. [less ▲]Detailed reference viewed: 69 (6 ULg)
Are Designers Sufficiently Instructed to Make the Most Rewarding Use of the Latest Steel Codes?
in 2013 SSRC Stability Conference (2013)
Series of comments stressing some points of Eurocode 3 which must be duly mastered to enable more economical design of steel structures.Detailed reference viewed: 29 (0 ULg)
Are deterministic models helpful to delineate groundwater protection zones in karstic aquifers ?
Dassargues, Alain ; Brouyère, Serge
in Günay, G.; Johnson, I. (Eds.) Karst Waters & Environmental Impacts (Proc. of the 5th Int. Conf.) (1997)Detailed reference viewed: 23 (2 ULg)
Are diatoms good integrators of temporal variability in stream water quality?
; ; Darchambeau, François et al
in Freshwater Biology (2008), 53(4), 827-841
1. Although diatoms have been used for many decades for river monitoring around the world, studies showing evidence that diatoms integrate temporal variability in water chemistry are scarce. 2. The ... [more ▼]
1. Although diatoms have been used for many decades for river monitoring around the world, studies showing evidence that diatoms integrate temporal variability in water chemistry are scarce. 2. The purpose of this study was to evaluate the response of the Eastern Canadian Diatom Index (IDEC: Indice Diatomees de l'Est du Canada) with respect to temporal water chemistry variability using three different spatio-temporal data sets. 3. Along a large phosphorus gradient, the IDEC was highly correlated with averaged water chemistry data. Along within-stream phosphorus gradients, the IDEC integrated phosphorus over various periods of time, depending on the trophic status of the site studied (Boyer, Nicolet or Ste. Anne river) and variability in nutrient concentration. 4. In the Ste. Anne River, where nutrient concentrations were low and generally stable, an input of phosphorus induced a rapid change in diatom community structure and IDEC value within the following week. In the mesotrophic Nicolet River, the observed integration period was approximately 2 weeks. Diatom communities in the eutrophic Boyer River appeared to be adapted to frequent and significant fluctuations in nutrient concentrations. In this system, the IDEC therefore showed a slower response to short term fluctuations and integrated nutrient concentrations over a period of 5 weeks. 5. Our results suggest that the integration period varies as a function of trophic status and nutrient concentration variability in the streams. Oligotrophic streams are more sensitive to nutrient variations and their diatom communities are directly altered by nutrient increase, while diatom communities of eutrophic rivers are less sensitive to nutrient fluctuations and major variations take a longer time to be integrated into index values. 6. The longer integration period in the eutrophic environment may be attributed to the complexity of the diatom community. The results from this study showed that the diversity and evenness of the communities increased with trophic status. [less ▲]Detailed reference viewed: 35 (0 ULg)
Are ecological indices based on macrophytes communities pertinent tools to monitor ecological potential of Walloon reservoirs?
Sossey Alaoui, Khadija ; ; Rosillon, Francis
Poster (2012, June 19)
Diversity and trophic metrics based on macrophyte communities were calculated to test their pertinence to assess the ecological potential of Walloon reservoirs (Belgium). The BE-FL method (four ... [more ▼]
Diversity and trophic metrics based on macrophyte communities were calculated to test their pertinence to assess the ecological potential of Walloon reservoirs (Belgium). The BE-FL method (four complementary metrics) and the United Kingdom method (five metrics calculated using information on taxonomic composition and abundance of macrophyte species and groups of such species) were tested. Highly significant correlations were found between the chemical variables (o-P (mg P/l); P tot (µg P/l); NH4+ (mg N/l) DCO (mg/l) Cond (µS/cm), the phytoplankton assemblage index, Q (Padisak et al., 2006) applied for the same reservoirs (Descy et al., 2010). and trophic metric LMNI and between them and the abundance of disturbance indicators (V). Groupe of macrfophyte species metrics do not necessarily provide any direct information on the quality or degree of degradation of the environment from which the sample was taken, whereas trophic indices do. [less ▲]Detailed reference viewed: 25 (1 ULg)
Are Education Professionals always vectors of solidarity-based social protection systems?
Poncelet, Marc ; ; et al
Teachers are a ‘homogeneous’ socioprofessional category, which is organised and open to involvement and the promotion of a shared interest. They are an essential component of civil society on the edge or ... [more ▼]
Teachers are a ‘homogeneous’ socioprofessional category, which is organised and open to involvement and the promotion of a shared interest. They are an essential component of civil society on the edge or at the heart of the public sector. Whether or not they are integrated into the public sector, they share values: promotion of individuals, the emancipation and elevation of individuals, and social well-being. All of these elements are aspects which make teachers naturally open to mutual solidarity. They can fully assess the advantage of the mutual organisation as a complementary element to government social action or as a substitute for failing public authorities. They can ‘incarnate’ solidarity and reconstruct social links [less ▲]Detailed reference viewed: 18 (4 ULg)
Are electrografted polymers chemisorbed or physisorbed onto their substrate ?
; Gabriel, Sabine ; Jérôme, Christine et al
in Macromolecular Chemistry and Physics (2005), 206(12), 1216-1220
AFM-based single-molecule force spectroscopy was used to evaluate the mechanical strength of the link between a polymer and the substrate onto which the polymer is electrografted. Poly(N-succinimidyl ... [more ▼]
AFM-based single-molecule force spectroscopy was used to evaluate the mechanical strength of the link between a polymer and the substrate onto which the polymer is electrografted. Poly(N-succinimidyl acrylate) was electrografted onto gold substrates and brought into contact with an aminothiol-functionalized AFM tip. Bridging of single polymer chains resulting from the strong coupling between the activated esters on the polymer and amine groups on the tip was investigated. We found that the link between the polymer and the gold substrate can withstand a force far beyond the force characteristic for physisorption on gold. [less ▲]Detailed reference viewed: 22 (2 ULg)
Are event-based and time-based prospective memory affected in the same way by aging?
Bastin, Christine ; Meulemans, Thierry
in Proceedings of the Annual Meeting of the Belgian Psychological Society (2000)Detailed reference viewed: 10 (0 ULg)
Are expectancies and peers involved in the relation between depressive mood, anxiety and cannabis use in adolescence?
Schmits, Emilie ; Quertemont, Etienne ; Boulard, Aurore
Poster (2014, July 15)
Background: Cannabis is the most commonly used illicit drug among teenagers and depression is one of the most common psychopathologies in adolescence. The specific symptom of depressive mood is present in ... [more ▼]
Background: Cannabis is the most commonly used illicit drug among teenagers and depression is one of the most common psychopathologies in adolescence. The specific symptom of depressive mood is present in 30% to 40% of adolescents in regular school settings. Links between cannabis use and depression have been highlighted, especially in adolescence. But questions remain about the strength of the association between lifetime cannabis use, depressive mood and anxiety, and about the mechanism underpinning the link. Aim: The aim of this study was to clarify the relationship between depressive mood and lifetime cannabis use in adolescents, particularly through the mediating role of anxiety and cannabis use effect expectancies, and the moderating role of peer cannabis use. Methods: A questionnaire was administered to 1,246 Belgian teenagers aged 16–17 years. ANOVA, chi-square, logistic regressions and mediation/moderation analyses were carried out to model lifetime cannabis use. Results: Depressive mood was positively correlated with lifetime cannabis use. Social anxiety, trait-anxiety and cognitive impairment effect expectancies mediated the effect of depression on lifetime cannabis use. The direct effect of depression on lifetime cannabis use increased when mediators were introduced into the relation, revealing their suppressive effects. The number of peer cannabis users moderated this model. Conclusion: Findings are discussed in terms of potential risk factors (depressive mood) or protective factors (anxiety and expectancies) for lifetime cannabis use, including the self-medication hypothesis. [less ▲]Detailed reference viewed: 45 (17 ULg)
Are Fair Trade Organizations necessarily Social Enterprises?
Huybrechts, Benjamin ; Defourny, Jacques
in Social Enterprise Journal (2008), 4(3), 186-201
Purpose – Fair trade organisations (FTOs) have been taken quite early as examples of Social Enterprises (SE) and have contributed to the shaping of the SE concept. The purpose of this paper is to examine ... [more ▼]
Purpose – Fair trade organisations (FTOs) have been taken quite early as examples of Social Enterprises (SE) and have contributed to the shaping of the SE concept. The purpose of this paper is to examine more deeply the link between FTOs and SE, both at a conceptual and at an empirical level. Design/methodology/approach – First, different theoretical frameworks of SE are introduced and confront FT to each of these frameworks. The second step is an empirical study of FTOs across four European countries to illustrate and deepen the links between FT and SE, focusing on the goals and the governance structures of FTOs. Findings – All the FTOs combine in some way economic, social and sometimes also political goals. FTOs are thus coherent to the “hybrid goals” nature of SEs. FTOs' governance is also quite specific and often innovative in terms of organisational architecture and stakeholders' involvement. Some FTOs are closer to the European – participatory – approach while others are closer to US – individual – approaches. Finally, the governance structures of FTOs seem to reflect quite well their goal mix. Research limitations/implications – This paper provides a more solid basis for the often implicit link between FT and SE. Future researches could use this work to explore specific topics of the SE literature in the context of FT (e.g. stakeholders' involvement). The FT example could also be used to examine further the shifting boundaries of the SE reality. Originality/value – The originality of this paper is to apply the SE concept to a specific field and to show how, within this field, there is at the same time a diversity of organisations, reflecting the diversity of SE approaches; and a range of specific features (especially in terms of goal mix and governance) distinguishing SEs from other types of organisations. [less ▲]Detailed reference viewed: 226 (17 ULg)
Are fasting and postload insulin good markers of cardiovascular risk factors?
Saint-Remy, Annie ; Scheen, André ; LEFEBVRE, Pierre et al
Conference (1997, December 11)Detailed reference viewed: 18 (0 ULg)