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See detailPRESSÃO PARCIAL (PCO2) E FLUXO DE DIÓXIDO DE CARBONO (CO2) EM AMBIENTES DE VÁRZEA AMAZÔNICOS
Amaral, JHF; Barbosa; Kasper, D et al

Conference (2015, July 12)

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See detailDevelopment, validation and comparison of NIR and Raman methods for the identification and assay of poor-quality oral quinine drops.
Mbinze Kidenge, Jérémie; Sacre, Pierre-Yves ULg; Yemoa, Achille et al

in Journal of Pharmaceutical & Biomedical Analysis (2015), 111

Poor quality antimalarial drugs are one of the public’s major health problems in Africa. The depth of this problem may be explained in part by the lack of effective enforcement and the lack of efficient ... [more ▼]

Poor quality antimalarial drugs are one of the public’s major health problems in Africa. The depth of this problem may be explained in part by the lack of effective enforcement and the lack of efficient local drug analysis laboratories. To tackle part of this issue, two spectroscopic methods with the ability to detect and to quantify quinine dihydrochloride in children’s oral drops formulations were developed and validated. Raman and Near Infrared (NIR) spectroscopy were selected for the drug analysis due to their low cost, non-destructive and rapid characteristics. Both of the methods developed were successfully validated using the total error approach in the range of 50-150% of the target concentration (20% W/V) within the 10% acceptance limits. Samples collected on the Congolese pharmaceutical market were analyzed by both techniques to detect potentially substandard drugs. After a comparison of the analytical performance of both methods, it has been decided to implement the method based on NIR spectroscopy to perform the routine analysis of quinine oral drop samples in the Quality Control Laboratory of Drugs at the University of Kinshasa (DRC). [less ▲]

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See detailAn ecosystem-scale perspective of the net land methanol flux: synthesis of micrometeorological flux measurements
Wohlfahrt, G.; Amelynck, C.; Ammann, C. et al

in Atmospheric Chemistry and Physics (2015), (15), 7413-7427

Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of living plants ... [more ▼]

Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of living plants as the major source and the reaction with OH as the major sink of methanol, global methanol budgets diverge considerably in terms of source/sink estimates, reflecting uncertainties in the approaches used to model and the empirical data used to separately constrain these terms. Here we compiled micrometeorological methanol flux data from eight different study sites and reviewed the corresponding literature in order to provide a first cross-site synthesis of the terrestrial ecosystem-scale methanol exchange and present an independent data-driven view of the land–atmosphere methanol exchange. Our study shows that the controls of plant growth on production, and thus the methanol emission magnitude, as well as stomatal conductance on the hourly methanol emission variability, established at the leaf level, hold across sites at the ecosystem level. Unequivocal evidence for bi-directional methanol exchange at the ecosystem scale is presented. Deposition, which at some sites even exceeds methanol emissions, represents an emerging feature of ecosystem-scale measurements and is likely related to environmental factors favouring the formation of surface wetness. Methanol may adsorb to or dissolve in this surface water and eventually be chemically or biologically removed from it. Management activities in agriculture and forestry are shown to increase local methanol emission by orders of magnitude; however, they are neglected at present in global budgets. While contemporary net land methanol budgets are overall consistent with the grand mean of the micrometeorological methanol flux measurements, we caution that the present approach of simulating methanol emission and deposition separately is prone to opposing systematic errors and does not allow for full advantage to be taken of the rich information content of micrometeorological flux measurements. [less ▲]

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See detailCompte rendu de Sagaert (Claudine), Histoire de la laideur féminine
Duchesne, Caroline ULg

in Lectures (2015)

Parcourant les successives perceptions de la laideur féminine de l’Antiquité à nos jours, l’étude que propose Claudine Sagaert, docteur en sociologie, adopte une approche pluridisciplinaire que vient ... [more ▼]

Parcourant les successives perceptions de la laideur féminine de l’Antiquité à nos jours, l’étude que propose Claudine Sagaert, docteur en sociologie, adopte une approche pluridisciplinaire que vient soutenir un riche corpus empruntant à la philosophie, à l’anthropologie, aux sciences médicales et encore à la littérature. [less ▲]

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See detailAlgorithmic aspects of converting surface mesh data to volumetric images
Plougonven, Erwan ULg; Léonard, Angélique ULg

Conference (2015, July 09)

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data ... [more ▼]

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data, point sets, finite elements, vector fields, implicit surfaces, graphs, basic shapes (spheres, cylinders, or cubes), etc. The work presented here discusses the problem of converting a triangulated surface mesh to a 3D image, a need that arises for example when using active surface-type segmentation methods of 3D images, shape-fitting, or combining data from laser surface scanning with 3D imaging. During the course of numerous projects, two main classes of mesh-to-image conversions have appeared: those identifying voxels (pixels in a 3D image) that intersect the mesh, or voxels that are contained in the mesh, supposing it defines a closed surface. [less ▲]

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See detailDoes formal child care availability for 0-3 year olds boost mothers' employment rate? Panel data based evidence from Belgium
Dujardin, Claire; Fonder, Muriel; Lejeune, Bernard ULg

E-print/Working paper (2015)

In 2003, a new multi-annual program aimed at increasing the availability of formal child care for 0-3 year old children was launched in Wallonia, the French-speaking part of Belgium. This paper is ... [more ▼]

In 2003, a new multi-annual program aimed at increasing the availability of formal child care for 0-3 year old children was launched in Wallonia, the French-speaking part of Belgium. This paper is interested in evaluating if this increased availability of formal child care resulted in a higher employment rate for women with at least one child under 3. To this end, we use a difference-in-differences approach based on municipality-level panel data, taking advantage of the fact that the increase in availability of formal child care differed greatly across municipalities. We find that the raise in child care availability significantly increased the maternal employment rate, but to a lesser extent than expected, most likely because of a substantial crowding-out effect. [less ▲]

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See detailBeyond indiscipline of Labor Market Intermediaries : The Case of Public Employment Services and Private Providers Partnerships
Remy, Céline ULg; Beuker, Laura ULg; Gérard, Julie ULg

Conference (2015, July 08)

Following the economic and social changes in the countries of the European Union (liberalization requirements, crisis of the welfare State, diversification of users expectations, etc.), compelling ... [more ▼]

Following the economic and social changes in the countries of the European Union (liberalization requirements, crisis of the welfare State, diversification of users expectations, etc.), compelling readability needs and modernization of Public Employment Services (PES) have appeared. Meanwhile, a spectacular growth of private employment operators - market and non-market - was recognized by the International Labor Organization in all member states, in order to respond effectively to the increased requests of support and training for the beneficiaries of the PES. In this new context, PES are invited by the European Union (EU) – particularly through its multiple directives – to rethink and reposition their traditional activities of placement, training and support for jobseekers according to a "mixed" management of the labor market. Therefore, PES entrust operation and management of their activities to private providers, as part of a contractual agreement. In this way, these operators provide a "back office function for SPE via a system of delegation governed by a specific division of labor formalized in a partnership agreement between PES and the private provider". Thus, these private labor market intermediaries (LMI’s) as active members on the public orders market work both on their own behalf and on behalf of the public authority. These new collaborations, qualified public-private partnerships (PPPs), allow PES to outsource and delegate a part of their missions they could not achieve internally. So PES combine the role of "actor" and the role of "manager" / "principal" in the labor market. To facilitate the coordination of their activities with the private sector, PES made the decision to create a partnerships service. The officers of this service have the mission to oversee this new form of regulation of the labor market. While collaboration rules are initially determined by the PES, the agents are required to implement them and have the private operators following them. Our interest is to study how these actors – or stakeholder of the PPPs – implement this public action device. Despite differences in both organizational and cultural (for instance bureaucratic rigidity versus informal structure, constraint reporting, management autonomy, etc.), public and private actors work together to serve community and beneficiaries of the PES for their professional integration in the labor market. To analyze how these actors interact and live the partnership relationship, established between agreement and disagreement, we will rely on the economy of conventions and especially on the theoretical contributions of the Theory of justification. In this way, we will identify the different logics of action (present in the merchant, civic, industrial worlds, etc.) that guide the practices of stakeholders, from their discourse and in particular the underlying arguments to justify their actions. Our analysis is rooted in empirical material composed of semi-structured interviews (N=89) and various observations of interactions made within the partnership services and with providers (N=132). These observations focused on three key moments in the life of the partnership: the selection of projects, the monitoring and evaluation of projects by the agents. With this approach, our goal is twofold. On the one hand, we want to highlight the moments when the actors "interpret" the regulatory framework that structure their actions within the partnership relationship. On the other hand, we want to understand the arguments used by actors to justify and legitimize their indiscipline. [less ▲]

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See detailShewhart Control Charts with Guaranteed In-Control Performance
Faraz, Alireza ULg; Heuchenne, Cédric ULg; Woodall, W.H.

Conference (2015, July 08)

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See detailStress constrained topology optimization for additive manufacturing: Specific character and solution aspects
Duysinx, Pierre ULg

Conference (2015, July 07)

Since the fundamental work by Bendsøe and Kikuchi (1988), topology optimization has been based on compliance type formulations (Bendsoe & Sigmund, 2003) while the number of works considering stress ... [more ▼]

Since the fundamental work by Bendsøe and Kikuchi (1988), topology optimization has been based on compliance type formulations (Bendsoe & Sigmund, 2003) while the number of works considering stress constraints are rather limited (Duysinx & Bendsoe, 1998). More recently the generalized shape optimization approach using level set methods (see for instance Allaire, Jouve, Troader, 2004, Belytchko, Xiao, Parimi, 2003) has followed the tracks of topology optimization and has mainly been focusing on compliance minimization problems. The ‘compliance type’ formulation has produced quite interesting results in many problems because controlling the energy and the displacements under the loads is generally favourable for deflection control and because, for one load case, the compliance minimization leads to a fully stressed design nearly everywhere in the structure. However there are theoretical results that clearly show that the strongest and the stiffest structural layout can be quite different. As demonstrated in Rozvany & Birker (1994) truss topology optimization can lead to different results when there are several load cases, different stress limits in tension and compression, or when there are several materials involved. Therefore, the first goal of the paper points out the importance of considering stress constraints as soon as the preliminary design phase, that is, to include stress constraints in the topology optimization problem. Revisiting some contributions of the authors, this paper aims at illustrating the key role of stress constraints in the framework of topology optimization of continuum structures. The recent developments are able to treat: • Integrated stress criteria (i.e. global) relaxed stress constraints that aggregate the stress constraints in each finite element in order to be able to circumvent the large scale character of the local stress constraints. • Stress criteria that are able to tackle non equal stress limits in tension and compression. The usual von Mises criterion is unable to predict real-life designs when the structure is made of materials with unequal stress limits like concrete or composite materials. These different behaviours in tension and compression result in quite specific designs. Numerical applications make possible to point out the different nature of structural lay out for maximum strength and maximum stiffness. This one is clearly demonstrated in two kinds of particular situations: once several load cases are considered and when unequal stress limits in tension and compression are involved. The second contribution of the paper deals with the solution aspects of large scale constrained optimization problems. Because of the huge number of design variables, dual methods combined with local convex approximations such as CONLIN (Fleury, 1989) or MMA (Svanberg, 1987) are well indicated to solve classical topology optimization methods. However stress constrained problems introduce also a so large number of active constraints that one comes to a rather delicate situation. We show that the optimizer effort increases mostly as the cube of the number of constraints. In order to circumvent the problem, the idea developed in the paper is to combine first or second order approximations (Bruyneel, Duysinx, Fleury, 2002) with zero order approximations of stress constraints, especially for the subset of restrictions that are likely not to be active or not to change too fast. At first the paper presents the way to derive zero-order approximations of -relaxed stress constraints (that is necessary to cope with the singularity phenomenon of stress constraints in topology optimization). Then the proposed hybrid approach mixing approximation of different orders is benchmarked on numerical applications illustrating the reduction of computation time for solving optimization problems without sacrifying to the robustness and efficiency. Numerical applications will investigate topology optimized benchmark examples combined with additive manufacturing fabrication to illustrate the developments. [less ▲]

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See detailMethane distributions and sea-to-air fluxes in the South China Sea and the West Philippines Sea
Tseng; Chen; Borges, Alberto ULg et al

Poster (2015, July 07)

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See detailModelling Uncertainties in Long-Term Predictions of Urban Growth: A Coupled Cellular Automata and Agent-Based Approach
El Saeid Mustafa, Ahmed Mohamed ULg; Saadi, Ismaïl ULg; Cools, Mario ULg et al

in Ferreira, Joseph; Goodspeed, Robert (Eds.) Proceedings of CUPUM 2015 (2015, July 07)

Modelling the growth of urban settlements is of considerable interest for different applications, amongst which integrated flood management. This study aims at modelling urban growth for a long time ... [more ▼]

Modelling the growth of urban settlements is of considerable interest for different applications, amongst which integrated flood management. This study aims at modelling urban growth for a long time horizon up to 2100 and to integrate the model outcomes with a hydrological model for the same time horizon. Forecasting land-use change over such time frames entails very significant uncertainties. In this regard, the main focus of this paper is attributed to the handling of uncertainty in an urban growth model. To this end, we examine a Monte Carlo Simulation method, which is integrated in the proposed urban growth model. Transition probabilities for each non-urban cell are estimated by a coupled Cellular Automata-Agent-Based ap-proach. The results help to handle uncertainty over long time horizons and to assess the increment in degree of uncertainty at every time-step. [less ▲]

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See detailCO2-sourced non-isocyanate polyurethanes: from the monomer synthesis to the elaboration of polymeric materials
Gennen, Sandro ULg; Grignard, Bruno ULg; Gilbert, Bernard ULg et al

Conference (2015, July 07)

Due to problems related to the rarefaction of fossil resources and the global warming that comes from CO2 emissions, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and ... [more ▼]

Due to problems related to the rarefaction of fossil resources and the global warming that comes from CO2 emissions, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and environmentally friendly must be explored to produce chemicals. Besides the valorization of bio-based raw materials, the use of CO2 as a C1 carbon source into added-value products has gained interest in both academic and industrial fields. One promising way to valorize CO2 relies on its chemical fixation onto epoxides to produce cyclic carbonates that find applications as electrolytes in lithium ion batteries, as aprotic polar solvents or as useful intermediates for polycarbonates. Cyclic carbonates also react with primary amines to produce 2-hydroxyethylurethane. This reaction can be extrapolated to the synthesis of non-isocyanate polyurethanes (NIPU) by polyaddition of bifunctional cyclic carbonates with diamines.5 This study focusses on (i) the synthesis of cyclic carbonates using new highly efficient organocatalysts and (ii) their valorization as monomers to produce non-isocyanate polyurethanes. First, we have identified a bicomponent organocatalyst for the very fast synthesis of cyclic carbonates from CO2 and epoxides under very mild reaction conditions. Kinetics of reactions were followed by online Raman spectroscopy. NMR titrations were realized to evidence the mechanism of activation of this novel organocatalytic system that will be discussed in detail this talk. The second objective relies on the development of new efficient organocatalysts for the synthesis of high molar masses NIPUs in short reaction times. Organic compounds interacting with the cyclic carbonate by hydrogen bonding were identified and their catalytic activity was highlighted by a model reaction between ethylene carbonate and a primary amine before extrapolation to the synthesis of NIPUs that find applications as coatings or foamed materials. [less ▲]

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See detailGénétique et biologie de la conservation du desman des Pyrénées (Galemys pyrenaicus) en France
Gillet, François ULg

Doctoral thesis (2015)

The Pyrenean desman (Galemys pyrenaicus) is a semi-aquatic mammal endemic to the Iberian Peninsula and the Pyrenees and classified as “vulnerable” by the IUCN. The aims of this PhD thesis, part of a ... [more ▼]

The Pyrenean desman (Galemys pyrenaicus) is a semi-aquatic mammal endemic to the Iberian Peninsula and the Pyrenees and classified as “vulnerable” by the IUCN. The aims of this PhD thesis, part of a National Action Plan, were to improve the knowledge on this species by the development of molecular tools (species identification by sequencing of a fragment of the cytochrome b gene and by RFLP, creation and amplification of polymorphic microsatellites). A genetic structure of three populations associated with low levels of genetic diversity has been evidenced in the French Pyrenees. In addition, the molecular analysis of its diet (COI gene) has allowed to identify its foraging areas and an individual survey on a stretch of river has revealed long distance movements unsuspected before. These results may direct conservation measures for this species. [less ▲]

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