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See detailOn the Shape Simulation of Aggregate and Cement Particles in a DEM System
He, Huan; Stroeven, Piet; Pirard, Eric ULg et al

in Advances in Materials Science and Engineering (2015)

Aggregate occupies at least three-quarters of the volume of concrete, so its impact on concrete’s properties is significant. Both size and shape of aggregate influence workability, mechanical properties ... [more ▼]

Aggregate occupies at least three-quarters of the volume of concrete, so its impact on concrete’s properties is significant. Both size and shape of aggregate influence workability, mechanical properties, and durability of concrete. On the other hand, the shape of cement particles plays also an important role in the hydration process due to surface dissolution in the hardening process. Additionally, grain dispersion, shape, and size govern the pore percolation process that is of crucial importance for concrete durability. Discrete element modeling (DEM) is commonly employed for simulation of concrete structure. To be able to do so, the assessed grain shape should be implemented. The approaches for aggregate and cement structure simulation by a concurrent algorithm-based DEM system are discussed in this paper. Both aggregate and cement grains were experimentally analyzed by X-ray tomography method recently. The results provide a real experimental database, for example, surface area versus volume distribution, for simulation of particles in concrete technology. Optimum solutions are obtained by different simplified shapes proposed for aggregate and cement, respectively. In this way, more reliable concepts for aggregate structure and fresh cement paste can be simulated by a DEM system. [less ▲]

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See detailA performance comparison of sensitivity analysis methods for building energy models
Nguyen, Anh Tuan; Reiter, Sigrid ULg

in Building Simulation: An International Journal (2015), 8(6), 651-664

The choice of sensitivity analysis methods for a model often relies on the behavior of model outputs. However, many building energy models are “black-box” functions whose behavior of simulated results is ... [more ▼]

The choice of sensitivity analysis methods for a model often relies on the behavior of model outputs. However, many building energy models are “black-box” functions whose behavior of simulated results is usually unknown or uncertain. This situation raises a question of how to correctly choose a sensitivity analysis method and its settings for building simulation. A performance comparison of nine sensitivity analysis methods has been carried out by means of computational experiments and building energy simulation. A comprehensive test procedure using three benchmark functions and two real-world building energy models was proposed. The degree of complexity was gradually increased by carefully-chosen test problems. Performance of these methods was compared through the ranking of variables’ importance, variables’ sensitivity indices, interaction among variables, and computational cost for each method. Test results show the consistency between the Fourier Amplitude Sensitivity Test (FAST) and the Sobol method. Some evidences found from the tests indicate that performance of other methods was unstable, especially with the non-monotonic test problems. [less ▲]

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See detailWhen women support the patriarchal family. The dynamics of marriage in a Gécamines mining camp (Katanga province, DR Congo)
Rubbers, Benjamin ULg

in Journal of Historical Sociology (2015), 28(2), 213-234

Based on ethnographic research among the ex-Gécamines workers of Panda (Likasi, DR Congo), this article studies the dynamics of the spousal relationship in a post-industrial context that has been long ... [more ▼]

Based on ethnographic research among the ex-Gécamines workers of Panda (Likasi, DR Congo), this article studies the dynamics of the spousal relationship in a post-industrial context that has been long characterized by paternalism. The results of this research suggest that, though men and women living in this mining community talk about their spousal relationships by invoking the ideal of Christian marriage promoted during the colonial period, in practice such relationships faced important changes following Congolese independence in 1960. The nationalization and subsequent dramatic decline of Gécamines caused changes which directly affected three central dimensions of the colonial family model, namely monogamy, the ideal of domesticity, and male authority. If men and women continue to reference this model, it is because, in times of growing poverty, it allows spouses to remind one other of their respective duties as docile housewives and responsible husbands, and to command respect as virtuous Christian families in the local community. [less ▲]

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See detailHeadache during cryoballoon ablation for atrial Fibrillation
Pison, L; Peeters, P; Blaauw, Y et al

in Europace (2015), 17(6), 898-901

Objective Headache has been reported to occur during cryoballoon ablation for atrial fibrillation (AF). No study has systematically analyzed this phenomenon. Methods Twenty consecutive patients with ... [more ▼]

Objective Headache has been reported to occur during cryoballoon ablation for atrial fibrillation (AF). No study has systematically analyzed this phenomenon. Methods Twenty consecutive patients with symptomatic AF, underwent cryoballoon ablation without sedation. Headache was evaluated before, during and after the first cryoapplication in every pulmonary vein (PV) using a visual representation of a head for location of the headache, a numerical rating scale (NRS) for measuring pain intensity and the short-form McGill pain questionnaire (MPQ) for qualitative analysis of pain. The order in which the PVs were ablated, was randomized. Results Sixteen (80%) patients perceived mainly frontal headache during cryoablation. The overall NRS scores were significantly higher during (5.1±1.7), compared to before (2.7±1.4), and after (3.5±2.2) a cryoapplication (p<0.05). The NRS score was significantly higher during ablation of the first PV. The intensity of the perceived headache was not related to the temperature reached 150 s after initiation of a cryoapplication (p = 0,81). Of the MPQ, 3 sensory adjectives and 1 affective adjective averaged between score 1 and 2, representing mild to moderate severity of pain. Conclusions The majority of patients treated by balloon cryoablation, experienced headache during a cryoapplication. There was no correlation between the temperature reached during a cryoballoon freeze and the intensity of the headache. Cryoballoon ablation of the first PV, was significantly more painfull than the remaining PV [less ▲]

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See detailLe général de Gaulle et Antoing
Murez, Jean-Baptiste ULg

in Revue trimestrielle du cercle d'études Charles de Gaulle (2015), 137(Eté), 9-17

Quelques pages sur la relation entre Charles de Gaulle et le Collège Jésuite d'Antoing, où il fut élève durant l'année scolaire 1907-1908.

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See detailCycle Slips Detection in Quad-Frequency Mode: Galileo's Contribution to an Efficient Approach under Hogh Ionospheric Activity
Van de Vyvere, Laura ULg

in CLGE Student Contest (2015)

Cycle slips detection has always been a key issue in phase measurements accuracy, thus impacting positioning precision. Since Galileo is the first constellation to offer four carrier frequencies available ... [more ▼]

Cycle slips detection has always been a key issue in phase measurements accuracy, thus impacting positioning precision. Since Galileo is the first constellation to offer four carrier frequencies available in Open Service, we were able to develop an innovative detection algorithm, especially promising in harsh environment like high ionospheric activity. This improves previous dual and triple-frequency methods, whose efficiency was somehow limited in tricky situations, like ionospheric events or particular configurations. In our algorithm, two types of testing quantities were used: triple-frequency Simsky combination and dual-frequency Geometry-Free combination, each one being associated to a suitable detection algorithm. Simsky combination allows to detect almost every configuration, except for cycle slips of the same magnitude, appearing simultaneously on all carriers. Geometry-Free combination is only used to detect this particular case, since it suffers from quick variation of ionospheric delay. Together - through the choice of the most efficient combination alternatives - they enable the detection of any cycle slips configuration. This is now made possible thanks to the availability of data from Galileo’s four carriers. The quad-frequency algorithm has been tested on Galileo observations from both GMSD (Japan) and NKLG (Gabon) stations. On the first ones, cycle slips were artificially inserted in order to simulate particular cases and test algorithm robustness. NKLG raw data were used to assess algorithm behaviour for cases met in the equatorial area. Enhanced with a suitable cycle slip correction method and a real-time feature, our algorithm could directly be integrated into the software receiver, enabling the supply of continuous and corrected data to the user. In conclusion, this first quad-frequency cycle slips detection algorithm is obviously a step forward and every Galileo user will indeed be able to benefit from a highly better-quality positioning. With regard to precise positioning, this is yet another step reinforcing Galileo’s competitivity against other dual or triple-frequency GNSS. [less ▲]

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See detailGeophysical investigation of the Hockai Fault Zone, Eastern Belgium
Havenith, Hans-Balder ULg; Nguyen, Frédéric ULg; Halleux, Lucien ULg et al

in EGU General Assembly Conference Abstracts (2015)

In the frame of a regional project evaluating the geothermal potential of the Wallonian Region of Belgium, the Hockai Fault Zone has been identified as one of the most interesting targets. It is a ... [more ▼]

In the frame of a regional project evaluating the geothermal potential of the Wallonian Region of Belgium, the Hockai Fault Zone has been identified as one of the most interesting targets. It is a seismically active fault zone that hosted the largest historical earthquake in Northwestern Europe, the M6-6.5 Verviers event in 1692 as well as a swarm of small earthquakes that was recorded in 1989-90. On the surface, the presence of the fault zones is marked by a series of geomorphic features, such as several landslides near the borders in the northern part, repeated NW-SE oriented scarps all along the Eastern border (over a distance of 40 km), river diversions and captures with formation of paleo-valleys.... [less ▲]

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See detailToward the First Class of Suicide Inhibitors of Kallikreins Involved in Skin Diseases
Tan, Xiao; Soualmia, Feryel; Furio, Laetitia et al

in Journal of Medicinal Chemistry (2015), 58

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See detailBidding farewell? On the assessment of the structural or situational nature of the current crisis surrounding David Cameron's prospective referendum on Britain's continued membership of the European Union
Niessen, Annie ULg

Master's dissertation (2015)

Since David Cameron’s announcement for an 'in/out' referendum, Britain’s membership of the European Union has been in jeopardy. This recent crisis in the UK-EEC/EU relationship is far from being the first ... [more ▼]

Since David Cameron’s announcement for an 'in/out' referendum, Britain’s membership of the European Union has been in jeopardy. This recent crisis in the UK-EEC/EU relationship is far from being the first one. Indeed, the UK has acquired the reputation of a difficult Member State since his accession in 1973. My dissertation explores this relationship throughout the different crises that occurred under the successive premierships in order to answer the following research question: is the current crisis surrounding Cameron’s ‘in/out’ referendum a structural or a situational phenomenon? To that end, the dissertation body is divided into three parts. Part 1 deals with the legal and practical possibilities of withdrawal from the EU. Part 2 is a journey through the past UK-EEC/EU relationship with a focus on the crises and the reforms demanded by the former Prime Ministers. Part 3 focuses on the current crisis, exploring Cameron’s demands for reforms and comparing them with three other party leaders’ demands before the 2015 general election. [less ▲]

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See detailCarbon Multiplicity Editing in Long-Range Heteronuclear Correlation NMR Experiments: A Valuable Tool for the Structure Elucidation of Natural Products.
Sauri, Josep; Frederich, Michel ULg; Tchinda, Alembert T. et al

in Journal of natural products (2015), 78(9), 2236-41

A recently developed NMR method to simultaneously obtain both long-range heteronuclear correlations and carbon multiplicity information in a single experiment, ME-selHSQMBC, is demonstrated as a ... [more ▼]

A recently developed NMR method to simultaneously obtain both long-range heteronuclear correlations and carbon multiplicity information in a single experiment, ME-selHSQMBC, is demonstrated as a potentially useful technique for chemical shift assignment and structure elucidation of natural products presenting complicated NMR spectra. Carbon multiplicities, even for C/CH2 and odd for CH/CH3 resonances, can be distinguished directly from the relative positive/negative phase of cross-peaks. In addition, connectivity networks can be further extended by incorporating a TOCSY propagation step. Staurosporine (1) and sungucine (2) are utilized as model compounds to demonstrate these techniques. [less ▲]

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See detailAntrocarines A-F, antiplasmodial ergostane steroids from the stem bark of Antrocaryon klaineanum.
Douanla, Pascal D.; Tabopda, Turibio Kuiate; Tchinda, Alembert T. et al

in Phytochemistry (2015), 117

During a study on the chemistry and biological activity of Antrocaryon klaineanum Pierre, six new sterols including 4,24(28)-ergostadiene-6alpha,7alpha-diol (1), 6alpha-methoxy-4,24(28)-ergostadiene ... [more ▼]

During a study on the chemistry and biological activity of Antrocaryon klaineanum Pierre, six new sterols including 4,24(28)-ergostadiene-6alpha,7alpha-diol (1), 6alpha-methoxy-4,24(28)-ergostadiene-7alpha,20S-diol (2), 6alpha-methoxy-4,24(28)-ergostadien-7alpha-ol (3), 20S-hydroxy-24(28)-ergosten-3-one (4), 7alpha-hydroxy-4,24(28)-ergostadien-3-one (5), and 24(28)-ergostene-3beta,6alpha-diol (6) were characterized by physical and spectroscopic means. The known steroids 7 and 8 were also isolated. The crude extract and the isolated compounds were evaluated for their ability to inhibit the 3D7 strain of Plasmodium falciparum. Compounds 2, 3, and 8 showed potent activity while that of the crude extract was moderate. [less ▲]

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See detailNuclear magnetic resonance: a key metabolomics platform in the drug discovery process.
Leenders, Justine ULg; Frederich, Michel ULg; De Tullio, Pascal ULg

in Drug discovery today. Technologies (2015), 13

Metabolomics is an innovative tool that is now emerging in the drug discovery process. Indeed, its ability to follow the dynamic perturbations in the metabolome resulting from pathologies but also from ... [more ▼]

Metabolomics is an innovative tool that is now emerging in the drug discovery process. Indeed, its ability to follow the dynamic perturbations in the metabolome resulting from pathologies but also from drug treatment and or/toxicity is of value for the development of new therapeutic approaches. Nuclear magnetic resonance (NMR) spectroscopy, which is an important analytical technique for several steps of the lead discovery, validation and optimization processes, has been described, together with mass spectrometry (MS) as one of the major platform that could be used for metabolomics studies. This review highlights why NMR could be considered a key tool for the application of metabolomics in drug discovery. [less ▲]

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See detailStructure-activity relationship of hybrids of Cinchona alkaloids and bile acids with in vitro antiplasmodial and antitrypanosomal activities.
Leverrier, Aurelie; Bero, Joanne; Cabrera, Julian et al

in European journal of medicinal chemistry (2015), 100

In this work, a series of hybrid compounds were tested as antiparasitic substances. These hybrids were prepared from bile acids and a series of antiparasitic Cinchona alkaloids by the formation of a ... [more ▼]

In this work, a series of hybrid compounds were tested as antiparasitic substances. These hybrids were prepared from bile acids and a series of antiparasitic Cinchona alkaloids by the formation of a covalent C-C bond via a decarboxylative Barton-Zard reaction between the two entities. The bile acids showed only weak antiparasitic properties, but all the hybrids exhibited high in vitro activities (IC50: 0.48-5.39 muM) against Trypanosoma brucei. These hybrids were more active than their respective parent alkaloids (up to a 135 fold increase in activity), and displayed good selectivity indices. Aditionally, all these compounds inhibited the in vitro growth of a chloroquine-sensitive strain of Plasmodium falciparum (3D7: IC50: 36.1 nM to 8.72 muM), and the most active hybrids had IC50s comparable to that of artemisinin (IC50: 36 nM). Some structure-activity relationships among the group of 48 hybrids are discussed. The increase in antiparasitic activity may be explained by an improvement in bioavailability, since the more lipophilic derivatives showed the lowest IC50s. [less ▲]

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See detailDismantling the treasured flagship lichen Sticta fuliginosa (Peltigerales) into four species in Western Europe
Magain, Nicolas; Sérusiaux, Emmanuël ULg

in Mycological Progress (2015), 14:97

In the framework of a worldwide project on the phylogeny of the lichen genus Sticta, dedicated sampling was performed in four regions of Western Europe, roughly along an East-West line between N 48°02’ E ... [more ▼]

In the framework of a worldwide project on the phylogeny of the lichen genus Sticta, dedicated sampling was performed in four regions of Western Europe, roughly along an East-West line between N 48°02’ E 07°01’ and N 52°01’ W 09°30’, ranging from France/Vosges to Ireland/Kerry. Five clearly distinct ITS haplotypes were detected for isidia-producing species where only two were expected. Subtle anatomical and morphological characters, together with a strongly supported 4-loci molecular phylogeny, permit to distinguish, besides the easily recognized S. canariensis and S. limbata: • the two « well-known » S. fuliginosa and S. sylvatica whose type collections have been carefully reassessed; the former is widespread in both hemispheres, while the latter is correctly identified only from continental Europe and the Andes in Colombia; the barcode ITS of S. fuliginosa differs by a single substitution from S. limbata (with a single exception), and the 4-loci phylogenetic tree does not resolve them as distinct lineages, most probably highlighting a very recent divergence and incomplete lineage sorting; • three species that were formely included in S. fuliginosa: the resurrected S. ciliata Taylor, belonging to a complex group yet to be disentangled and occurring in the Neotropics, Africa, Macaronesia and Western Europe, and two species described as new for science, S. fuliginoides, found in continental Europe, the Canary Islands, eastern North America and Colombia, and S. atlantica only known from Ireland and the Azores archipelago. Molecular inferences demonstrate active divergence and dispersion within S. ciliata that may require recognition of further species. Fresh material can be identified with a morphological and anatomical preliminary key provided here. We propose that the taxonomy of all lichen species be urgently reviewed in the light of molecular data in an evolutionary context, particularly those used as bioindicators of environmental change and woodland management. [less ▲]

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See detailSociety and materials, a series of regular seminars based on a dialog between soft and hard sciences
Birat, Jean-Pierre; Declich, Andrea; Belboom, Sandra ULg et al

in Metallurgical Research & Technology (2015), 112(5),

An informal community has regularly organized annual conferences in Europe since 2007, on the connection between core commodities like materials and society and societal challenges: they are called SAM ... [more ▼]

An informal community has regularly organized annual conferences in Europe since 2007, on the connection between core commodities like materials and society and societal challenges: they are called SAM (Society and Materials). The approach is trans- and multi-disciplinary. Thus, sociologists, historians, architects, political scientists and policymakers, engineers, material scientists, life cycle community experts, business people and philosophers come together each year in cohorts of about 100 people from Europe, but also Asia, America and Africa, to give 30 to 40 presentations. They are made available on the SOVAMAT website (www.sovamat.org) and are published in journals like Revue de Métallurgie, Metallurgical Research & Technology and Matériaux et Techniques: Many kinds of materials are regularly discussed. Until today, the conferences have produced about 350 communications, many of which have been translated into peer-reviewed papers. These series of conferences were launched in order to address the complexity of technology evolution in the context of societal challenges. The intuition was that purely mono-disciplinary approaches would not be sufficient to address the future and that holistic methods like Life Cycle Analysis were still too narrowly focused to lead seamlessly to what was needed. Inviting separate communities to participate turned out to be quite popular and people have been coming back regularly and have attracted new players. The outcome is a mixture of disciplines speaking together, but also of practical proposals alongside methodological, meta- or ontological ones. With the hindsight of 10 years of practical experience, it is clear that the scientific agenda in terms of methodology, which was set at the beginning of the adventure, has been achieved. The paths followed were somewhat different, more empirical and more imaginative, than the initial vision of the organizers: a cluster of approaches was explored, which turned out to be richer than an improved version of LCA and MFA. Moreover, new issues have been raised, which make it likely that the initiative will continue indefinitely. This experience can probably help others find their way forward. [less ▲]

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