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See detailHigher Symmetries of the Laplacian via Quantization
Michel, Jean-Philippe ULg

in Annales de l'Institut Fourier (2014), 64

We develop a new approach, based on quantization methods, to study higher symmetries of invariant di erential operators. We focus here on conformally invariant powers of the Laplacian over a conformally ... [more ▼]

We develop a new approach, based on quantization methods, to study higher symmetries of invariant di erential operators. We focus here on conformally invariant powers of the Laplacian over a conformally at manifold and recover results of Eastwood, Leistner, Gover and ilhan. In particular, conformally equivariant quantization establishes a correspondence between the algebra of Hamiltonian symmetries of the null geodesic ow and the algebra of higher symmetries of the conformal Laplacian. Combined with a symplectic reduction, this leads to a quantization of the minimal nilpotent coadjoint orbit of the conformal group. The star-deformation of its algebra of regular functions is isomorphic to the algebra of higher symmetries of the conformal Laplacian. Both identify with the quotient of the universal envelopping algebra by the Joseph ideal. [less ▲]

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See detailÉduquer à la démocratie : Protagoras et la question de l’égalité
Gavray, Marc-Antoine ULg

in MethIS : Méthodes et Interdisciplinarité en Sciences Humaines (2014)

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See detailPassive designs and strategies for low-cost housing using simulation-based optimization and different thermal comfort criteria
Nguyen, Anh Tuan ULg; Reiter, Sigrid ULg

in Journal of Building Performance Simulation [=JBPS] (2014), 7(1), 68-81

An optimum design of low-cost housing offers low-income urban inhabitants great opportunities to obtain a shelter at an affordable price and acceptable indoor thermal conditions. In this paper, the design ... [more ▼]

An optimum design of low-cost housing offers low-income urban inhabitants great opportunities to obtain a shelter at an affordable price and acceptable indoor thermal conditions. In this paper, the design and operation of a low-cost dwelling were numerically optimized using a simulation-based approach. Three multi-objective cost functions including construction cost, thermal comfort performance and 50-year operating cost were applied for naturally ventilated and air-conditioned buildings. Thermal environment inside the house was controlled and assessed by two thermal comfort models. Optimization problems which consist of 18 design parameters and 6 ventilation strategies were examined by two population-based probabilistic optimization algorithms (particle swarm optimization and hybrid algorithm). Optimum designs corresponding to each objective function, differences in optimal solutions, energy saving by the adaptive comfort approach and optimization effectiveness were outlined. The optimization method used in this paper shows a considerable potential of comfort improvement, energy saving and operating cost reduction. [less ▲]

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See detailNovel Functions of Core Cell Cycle Regulators in Neuronal Migration
Godin, Juliette ULg; Nguyen, Laurent ULg

in Cellular and Molecular Control of Neuronal Migration (2014)

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See detailEmotional Facial Expression Recognition and Expressivity in Type I and Type II Alcohol Dependent Patients
Dethier, Marie ULg; El Hawa, Maya; Duchateau et al

in Journal of Nonverbal Behavior (2014), 38(1), 89-105

Objective: Alcohol dependent patients (ADs) are known to encounter severe interpersonal problems. Nonverbal communication skills are important for the development of healthy relationships. The present ... [more ▼]

Objective: Alcohol dependent patients (ADs) are known to encounter severe interpersonal problems. Nonverbal communication skills are important for the development of healthy relationships. The present study aimed to explore emotional facial expression (EFE) recognition and posed and spontaneous EFE expressivity in male ADs divided into two groups according to Cloninger’s typology and the impact of their interpersonal relationship quality on the potential nonverbal deficits. Method: Twenty type I ADs, twenty-one type II ADs, and twenty control participants took part in an EFE recognition task and an EFE expressivity task that considered personal emotional events (spontaneous expressivity) and EFE in response to a photo or word cue (posed expressivity). Coding was based on judges’ ratings of participants’ emotional facial expressions. Participants additionally completed a questionnaire on interpersonal relationship quality. Results: No difference between the three groups emerged in the EFE recognition task. Type II ADs showed heightened deficits compared with type I ADs in EFE expressivity: Judges perceived less accurate posed EFE in response to a cue word and less intense and positive spontaneous EFE in type II ADs compared to control participants. In addition, type II ADs reported more relationship difficulties compared to both type I ADs and control participants. These interpersonal relationship difficulties were related to some of the EFE expressivity deficits of AD-IIs. Conclusions: This study underlines the important differences between the interpersonal functioning of AD subtypes. [less ▲]

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See detailDynamic seasonal nitrogen cycling in response to anthropogenic N loading in a tropical catchment, Athi–Galana–Sabaki River, Kenya
Marwick, T. R.; Tamooh, F.; Ogwoka, B. et al

in Biogeosciences (2014), 11(2), 443--460

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See detaildivand-1.0: n-dimensional variational data analysis for ocean observations
Barth, Alexander ULg; Beckers, Jean-Marie ULg; Troupin, Charles ULg et al

in Geoscientific Model Development [=GMD] (2014), 7

A tool for multidimensional variational analysis (divand) is presented. It allows the interpolation and analysis of observations on curvilinear orthogonal grids in an arbitrary high dimensional space by ... [more ▼]

A tool for multidimensional variational analysis (divand) is presented. It allows the interpolation and analysis of observations on curvilinear orthogonal grids in an arbitrary high dimensional space by minimizing a cost function. This cost function penalizes the deviation from the observations, the deviation from a first guess and abruptly varying fields based on a given correlation length (potentially varying in space and time). Additional constraints can be added to this cost function such as an advection constraint which forces the analysed field to align with the ocean current. The method decouples naturally disconnected areas based on topography and topology. This is useful in oceanography where disconnected water masses often have different physical properties. Individual elements of the a priori and a posteriori error covariance matrix can also be computed, in particular expected error variances of the analysis. A multidimensional approach (as opposed to stacking 2-dimensional analysis) has the benefit of providing a smooth analysis in all dimensions, although the computational cost is increased. Primal (problem solved in the grid space) and dual formulations (problem solved in the observational space) are implemented using either direct solvers (based on Cholesky factorization) or iterative solvers (conjugate gradient method). In most applications the primal formulation with the direct solver is the fastest, especially if an a posteriori error estimate is needed. However, for correlated observation errors the dual formulation with an iterative solver is more efficient. The method is tested by using pseudo observations from a global model. The distribution of the observations is based on the position of the ARGO floats. The benefit of the 3-dimensional analysis (longitude, latitude and time) compared to 2-dimensional analysis (longitude and latitude) and the role of the advection constraint are highlighted. The tool divand is free software, and is distributed under the terms of the GPL license (http://modb.oce.ulg.ac.be/mediawiki/index.php/divand). [less ▲]

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See detailLand rights as an engine of growth ? An analysis of Cambodian landgrabs in the context of development theory
Rudi, Lisa-Marie; Azadi, Hossein; Witlox, Frank et al

in Land Use Policy (2014), (38), 564-572

Forceful evictions have become a serious problem in Cambodia with an increasing number of fami-lies being deprived of their land, homes and livelihoods without compensation. This article analysesCambodian ... [more ▼]

Forceful evictions have become a serious problem in Cambodia with an increasing number of fami-lies being deprived of their land, homes and livelihoods without compensation. This article analysesCambodian land rights in the context of economic development theory. It assesses whether increas-ing economic inequalities, stemming from forceful evictions, can be categorized as an impediment toCambodian economic growth. The Cambodian case illustrates that a lack of good governance due tocorruption leads to the unequal distribution of land which, in turn, causes inequitable economic devel-opment. The paper concludes that Cambodia is trapped in a vicious cycle of inequality, which is upheld byelites who benefit from evictions and land concessions while evictees become trapped in poverty. Giventhat the population is growing angrier, the article warns of potential for a violent revolution that couldhave disastrous consequences for the Cambodian kingdom, a country that recently emerged from yearsof civil conflicts and is still in the process of rebuilding its social fabric. [less ▲]

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See detailL'émotion fondamentale: Sartre et Bergson
Caeymaex, Florence ULg; Cormann, Grégory ULg

in Etudes Sartriennes (2014), 18

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See detailDeriving a global antioxidant score for commercial juices by multivariate graphical and scoring techniques: applications to blackcurrant juice
Tabart, Jessica; Kevers, Claire ULg; Dardenne, Nadia ULg et al

in Preedy (Ed.) Processing and Impact on Antioxidants in Beverages (2014)

Blackcurrants constitute an important source of potential health promoting phytochemicals (e.g. phenolic compounds, ascorbic acid) due to their antioxidant properties. Only small portions of berries are ... [more ▼]

Blackcurrants constitute an important source of potential health promoting phytochemicals (e.g. phenolic compounds, ascorbic acid) due to their antioxidant properties. Only small portions of berries are consumed fresh, most of their intake coming from processed foods, such as juices. Seven techniques were used to measure antioxidant capacity and antioxidant compounds of 10 juices. This yielded a large disparity of results. No single test, even the most popular ORAC assay, is able to compare the antioxidant capacity of similar food matrix such as blackcurrant juices. By combining tests from a large battery of « antioxidant » assays, it is possible to improve the discrimination of a food matrix by establishing a Global Antioxidant Score (GAS) which correlates well with graphical representations like Chernoff faces or stars. The latter approaches may help food industry managers and authorities to compare their « antioxidant » products with those existing on the market. [less ▲]

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See detailAntioxidant capacity of small dark fruits. Influence of cultivars and harvest time
Kevers, Claire ULg; PINCEMAIL, Joël ULg; Defraigne, Jean-Olivier ULg et al

in Journal of Berry Research (2014)

BACKGROUND: Small dark fruits represent one of the most important sources of bioactive compounds with antioxidant capacity in the human diet. The content of health-promoting antioxidants in these fruits ... [more ▼]

BACKGROUND: Small dark fruits represent one of the most important sources of bioactive compounds with antioxidant capacity in the human diet. The content of health-promoting antioxidants in these fruits may be important information to take into account when a fruit producer has to choose which cultivar to grow. OBJECTIVE: It is important to know how antioxidant capacity and antioxidant compounds as total phenolics and ascorbic acid vary between 9 small dark fruit species and for each species among cultivars (2 to 10 per species). METHODS: The antioxidant capacity (ORAC assay), total phenolic (Folin-Ciocalteu) and ascorbic acid content were measured in 9 fruits (plums, blackcurrants, blackberries, blueberries, cherries, redcurrants, raspberries, white currants and gooseberries) / 42 cultivars harvested at maturity during their high production period. RESULTS: The comparison of the average of the various cultivars of each small fruits showed that blackcurrants had the best antioxidant capacity (with plums), the highest ascorbic acid content and the highest total phenolic content (with blackberries). The present study shows that total phenolic compounds, ascorbic acid and antioxidant capacity strongly differed between genotypes of each small dark fruits. Other parameters as harvest time, culture conditions and maturity degree at the harvest may also influence the antioxidant capacity of small fruits. CONCLUSION: Among small dark fruits, blackcurrants have high qualities. Choices of variety, harvest time and maturity degree are important for all fruits. [less ▲]

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See detailEvaluating SGLT2 inhibitors for type 2 diabetes: pharmacokinetic and toxicological considerations.
Scheen, André ULg

in Expert opinion on drug metabolism & toxicology (2014)

Introduction: Inhibitors of sodium-glucose cotransporters type 2 (SGLT2), which increase urinary glucose excretion independently of insulin, are proposed as a novel approach for the management of type 2 ... [more ▼]

Introduction: Inhibitors of sodium-glucose cotransporters type 2 (SGLT2), which increase urinary glucose excretion independently of insulin, are proposed as a novel approach for the management of type 2 diabetes mellitus (T2DM). Areas covered: An extensive literature search was performed to analyze the pharmacokinetic characteristics, toxicological issues and safety concerns of SGLT2 inhibitors in humans. This review focuses on three compounds (dapagliflozin, canagliflozin, empagliflozin) with results obtained in healthy volunteers (including drug-drug interactions), patients with T2DM (single dose and multiple doses) and special populations (those with renal or hepatic impairment). Expert opinion: The three pharmacological agents share an excellent oral bioavailability, long half-life allowing once-daily administration, low accumulation index and renal clearance, the absence of active metabolites and a limited propensity to drug-drug interactions. No clinically relevant changes in pharmacokinetic parameters were observed in T2DM patients or in patients with mild/moderate renal or hepatic impairment. Adverse events are a slightly increased incidence of mycotic genital and rare benign urinary infections. SGLT2 inhibitors have the potential to reduce several cardiovascular risk factors, and cardiovascular outcome trials are currently ongoing. The best positioning of SGLT2 inhibitors in the armamentarium for treating T2DM is still a matter of debate. [less ▲]

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See detailEndothelial LGALS9 splice variant expression in endothelial cell biology and angiogenesis
Heusschen, Roy ULg; Schulkens, Iris; van Beijnum, Judy et al

in Biochimica et Biophysica Acta - Molecular Basis of Disease (2014)

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See detailAge-related decline in cognitive control: the role of fluid intelligence and processing speed
Manard, Marine ULg; Carabin, Delphine; Jaspar, Mathieu ULg et al

in BMC Neuroscience (2014), 15(7),

Background Research on cognitive control suggests an age-related decline in proactive control abilities whereas reactive control seems to remain intact. However, the reason of the differential age effect ... [more ▼]

Background Research on cognitive control suggests an age-related decline in proactive control abilities whereas reactive control seems to remain intact. However, the reason of the differential age effect on cognitive control efficiency is still unclear. This study investigated the potential influence of fluid intelligence and processing speed on the selective age-related decline in proactive control. Eighty young and 80 healthy older adults were included in this study. The participants were submitted to a working memory recognition paradigm, assessing proactive and reactive cognitive control by manipulating the interference level across items. Results Repeated measures ANOVAs and hierarchical linear regressions indicated that the ability to appropriately use cognitive control processes during aging seems to be at least partially affected by the amount of available cognitive resources (assessed by fluid intelligence and processing speed abilities). Conclusions This study highlights the potential role of cognitive resources on the selective age-related decline in proactive control, suggesting the importance of a more exhaustive approach considering the confounding variables during cognitive control assessment. [less ▲]

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See detailMicrobial heterogeneity affects bioprocess robustness: Dynamic single cell analysis contribute to understanding microbial populations
Delvigne, Frank ULg; Goffin, Philippe

in Biotechnology Journal (2014), 9(1), 61-72

Heterogeneity or segregation of microbial populations has been the subject of much research, but the real impact of this phenomenon on bioprocesses remains not well understood. The main reason behind this ... [more ▼]

Heterogeneity or segregation of microbial populations has been the subject of much research, but the real impact of this phenomenon on bioprocesses remains not well understood. The main reason behind this lack of knowledge is the difficulty for monitoring microbial population heterogeneity in dynamic process conditions. The main concepts leading to microbial population heterogeneity in the context of bioprocesses have been summarized by two distinct hypotheses. The first one involves the individual history of microbial cells or “path” followed during their residence time inside process equipment. The second one involves a coordinated response of the microbial population as a bet-hedging strategy in order to cope with process-related stresses. The respective contribution of each hypothesis to microbial heterogeneity in bioprocesses is still unclear. This statement illustrates the fact that, although microbial phenotypic heterogeneity has been thoroughly investigated at the fundamental level, the implications of this phenomenon in the context of microbial bioprocesses are still subjected to debate. At this time, automated flow cytometry is the best technique for the investigation of microbial heterogeneity in process conditions. However, dedicated software and relevant biomarkers are needed for its proper integration as a bioprocess control tool. [less ▲]

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See detailIsocinétisme et douleurs musculaires d’apparition retardée
Hody, Stéphanie ULg; ROGISTER, Bernard ULg; Leprince, Pierre ULg et al

in Movement & Sport Sciences - Science & Motricité (2014)

The curative and preventive efficiency of the isokinetic exercise, especially of the eccentric contraction, has been well demonstrated. However, intense or unusual eccentric exercise is known to induce ... [more ▼]

The curative and preventive efficiency of the isokinetic exercise, especially of the eccentric contraction, has been well demonstrated. However, intense or unusual eccentric exercise is known to induce muscle damage associated with delayed-onset muscle soreness (DOMS) and prolonged functional deficits. These negative consequences can frequently disturb the progress of re-education or training programmes. Since they can affect athletic performance and increase the risk of musculo-skeletal injuries, the structuro-functional alterations associated with DOMS may also be problematic in athletes. Therefore, to optimize the benefits of the eccentric work while avoiding muscle damage and occurrence of DOMS should represent a major objective for the practitioners. To date, the only systematic intervention that brings muscle protection against DOMS consists of performing repeated eccentric sessions at submaximal intensity. Besides its clinical use, isokinetic constitutes an interesting model to generate and investigate the DOMS phenomenon. The original association of eccentric injuring protocols with new emerging techniques of molecular biology appears to be a promising strategy to better understand the cellular and molecular mechanisms underlying exercise-induced muscle damage. Such data would provide better guidelines for prevention or treatment practice. [less ▲]

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See detailA Novel Strategy to Translate the Biomechanical Rupture Risk of Abdominal Aortic Aneurysms to their Equivalent Diameter Risk: Method and Retrospective Validation.
Gasser, T. C.; Nchimi, A.; Swedenborg, J. et al

in European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery (2014)

OBJECTIVE: To translate the individual abdominal aortic aneurysm (AAA) patient's biomechanical rupture risk profile to risk-equivalent diameters, and to retrospectively test their predictability in ... [more ▼]

OBJECTIVE: To translate the individual abdominal aortic aneurysm (AAA) patient's biomechanical rupture risk profile to risk-equivalent diameters, and to retrospectively test their predictability in ruptured and non-ruptured aneurysms. METHODS: Biomechanical parameters of ruptured and non-ruptured AAAs were retrospectively evaluated in a multicenter study. General patient data and high resolution computer tomography angiography (CTA) images from 203 non-ruptured and 40 ruptured aneurysmal infrarenal aortas. Three-dimensional AAA geometries were semi-automatically derived from CTA images. Finite element (FE) models were used to predict peak wall stress (PWS) and peak wall rupture index (PWRI) according to the individual anatomy, gender, blood pressure, intra-luminal thrombus (ILT) morphology, and relative aneurysm expansion. Average PWS diameter and PWRI diameter responses were evaluated, which allowed for the PWS equivalent and PWRI equivalent diameters for any individual aneurysm to be defined. RESULTS: PWS increased linearly and PWRI exponentially with respect to maximum AAA diameter. A size-adjusted analysis showed that PWS equivalent and PWRI equivalent diameters were increased by 7.5 mm (p = .013) and 14.0 mm (p < .001) in ruptured cases when compared to non-ruptured controls, respectively. In non-ruptured cases the PWRI equivalent diameters were increased by 13.2 mm (p < .001) in females when compared with males. CONCLUSIONS: Biomechanical parameters like PWS and PWRI allow for a highly individualized analysis by integrating factors that influence the risk of AAA rupture like geometry (degree of asymmetry, ILT morphology, etc.) and patient characteristics (gender, family history, blood pressure, etc.). PWRI and the reported annual risk of rupture increase similarly with the diameter. PWRI equivalent diameter expresses the PWRI through the diameter of the average AAA that has the same PWRI, i.e. is at the same biomechanical risk of rupture. Consequently, PWRI equivalent diameter facilitates a straightforward interpretation of biomechanical analysis and connects to diameter-based guidelines for AAA repair indication. PWRI equivalent diameter reflects an additional diagnostic parameter that may provide more accurate clinical data for AAA repair indication. [less ▲]

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See detailHigh Prevalence of Abdominal Aortic Aneurysm in Patients with Three-vessel Coronary Artery Disease.
Durieux, R.; VAN DAMME, Hendrik ULg; Labropoulos, N. et al

in European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery (2014)

OBJECTIVES: Currently, the prevalence of abdominal aortic aneurysm (AAA) in patients with coronary artery disease (CAD) and the correlation between CAD severity and AAA prevalence are not clearly known ... [more ▼]

OBJECTIVES: Currently, the prevalence of abdominal aortic aneurysm (AAA) in patients with coronary artery disease (CAD) and the correlation between CAD severity and AAA prevalence are not clearly known. We conducted a prospective study to determine the prevalence of AAA in patients undergoing coronary angiography and to determine the risk factors and a coronary profile associated with AAA. METHODS: Over an 18-month period, abdominal aortic ultrasound was performed on 1,000 patients undergoing coronary angiography for suspected or known CAD, or prior to valve surgery. Clinical characteristics and coronary profile were collected from the patients. RESULTS: The overall number of previously repaired, already diagnosed, and new cases of AAA in the study population was 42, yielding a prevalence of 4.2%. Among the patients with newly detected AAAs, only two had an AAA diameter of >54 mm and were therefore treated surgically. In men aged >/=65 years, the prevalence reached 8.6%, while in men with three-vessel CAD it was 14.4%. Multivariate analysis showed that age >/=65 years (p = .003), male gender (p = .003), family history of AAA (p = .01), current smoking (p = .002), and three-vessel CAD (p < .001) were significantly associated with a higher prevalence of AAA. CONCLUSION: The prevalence of AAA was high in men aged >/=65 years and in those with three-vessel CAD regardless of age. While our findings do not prove the cost-effectiveness of screening for AAA in these high risk patients, they do support the usefulness of a quick ultrasound examination of the abdominal aorta during routine transthoracic echocardiography in such patients. [less ▲]

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See detail*/es-'βɔl‐a‐/ v.intr. « quitter un lieu en s'élevant dans l'air ; se mouvoir dans l'air »
Baiwir, Esther ULg

in Buchi, Eva; Schweickard, Wolfgang (Eds.) Dictionnaire Étymologique Roman (DÉRom) (2014)

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