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See detailDetermination of phenolic organohalogens in human serum from a Belgian population and assessment of parameters affecting the human contamination
Dufour, Patrice ULg; PIRARD, Catherine ULg; CHARLIER, Corinne ULg

in Science of the Total Environment (2017), 599-600

Many in vitro or in vivo studies highlighted the potential deleterious effects of phenolic organohalogenated compounds (POHs) on the health, particularly on the thyroid system homeostasis, however few ... [more ▼]

Many in vitro or in vivo studies highlighted the potential deleterious effects of phenolic organohalogenated compounds (POHs) on the health, particularly on the thyroid system homeostasis, however few large scale human epidemiological studies have been carried out, especially in Europe. Further studies monitoring the human contamination by POHs, the sources of exposure and the influence of these compounds on thyroid health are still needed. Therefore we determined the concentrations of 16 POHs (pentachlorophenol (PCP), tetrabromobisphenol A (TBBPA), 4 bromophenols (BPs), 3 hydroxy-polybromodiphenylethers (OH-PBDEs) and 7 hydroxy-polychlorobiphenyls (OH-PCBs)) in serum from 274 people aged from 18 to 76 years old living in Liege (Belgium) and the surrounding area. A questionnaire about their alimentary habits, life style and home environment was also administered to the volunteers. The predominant compound measured in the population was PCP (median concentration of 593.0 pg mL−1). 4-OH-CB 107, 4-OH-CB 146 and 4-OH-CB 187 were detected in all samples and contributed for 75% of the sum of OH-PCBs (ΣOH-PCBs). The median measured in our population for ΣOH-PCBs was 143.7 pg mL−1. TBBPA and 2,4,6-tribromophenol were detected in 31% and 63.8% of the samples respectively while the detection frequency observed for the other BPs and the OH-PBDEs was close to zero. We computed multivariate regression models in order to assess the influence of demographic and lifestyle parameters on the PCP and ΣOH-PCBs contamination levels. Significant correlation was found between the PCP concentration and sex, smoker status, sea fish consumption and level of education, although the model seemed to be a poor (R2 = 0.14) predictor of the PCP concentration. The model computed for ΣOHPCBs was more explanatory (R2 = 0.61) and involved age, BMI and sea fish consumption. Finally, we assessed the parameters affecting the ΣOH-PCBs/ΣPCBs ratio. The model proposed involved age, BMI, smoker status and parent PCB level, and explained 41% of the variability of the ΣOH-PCBs/ΣPCBs ratio. [less ▲]

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See detailBarthes entre sémiologie et sémiotique : le cas de la photographie
Dondero, Maria Giulia ULg

in Bertrand, Jean-Pierre (Ed.) Roland Barthes : continuités (2017)

Dans cet article, je vise à reparcourir les textes que Barthes a écrits sur la photographie, sans aucune ambition philologique ni chronologique. Le but est plutôt de revenir sur les questions que le ... [more ▼]

Dans cet article, je vise à reparcourir les textes que Barthes a écrits sur la photographie, sans aucune ambition philologique ni chronologique. Le but est plutôt de revenir sur les questions que le médium photographique a posées à la sémiologie et continue, en partie, de poser à la sémiotique. La théorie barthésienne sera mise en contraste avec la sémiotique de l'image initiée par A.J. Greimas, et développée par l'Ecole de Paris (J.M. Floch, J. Fontanille...). [less ▲]

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See detailDu texte à la pratique : pour une sémiotique expérimentale
Dondero, Maria Giulia ULg

in Semiotica (2017), 218

Our essay aims at continuing the work of Jacques Fontanille, who developed a Semiotics of Practice next to a Semiotics of Text. This work, and especially Pratiques sémiotiques (2008), takes up a problem ... [more ▼]

Our essay aims at continuing the work of Jacques Fontanille, who developed a Semiotics of Practice next to a Semiotics of Text. This work, and especially Pratiques sémiotiques (2008), takes up a problem already formulated by Jean-Marie Floch in the article « Êtes-vous arpenteurs ou somnambules ? L’élaboration d’une typologie comportementale des voyageurs du métro » (1990). We will initially retrace the debate about the epistemological relationship between text and practice, outlining the forms of enunciative praxis. Secondly, we propose the concept of we will consider the visualization that we call ‘notation’: this analytical form of mediation between text and practice does not have the same status of in-vivo textualisations, but it works like an ex-post reconstruction which highlights the main gestures and exchanges while performing their grammaticalization. A more general aim of this essay is an enquiry into the legitimate objects of textual semiotics: what are the objects that it can analyze without betraying its principle of immanence, but also without being unable to analyze practice [less ▲]

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See detailL’événement énonciatif en sémiotique de l’image : de Roland Barthes à la sémiotique tensive
Dondero, Maria Giulia ULg; Colas-Blaise, Marion

in La part de l'oeil (2017), 31

Dans cet article, nous visons à montrer que la sémiotique tensive développée par Zilberberg permet de revisiter utilement les notions barthésiennes de studium et de punctum et, leur permet de surcroît, de ... [more ▼]

Dans cet article, nous visons à montrer que la sémiotique tensive développée par Zilberberg permet de revisiter utilement les notions barthésiennes de studium et de punctum et, leur permet de surcroît, de devenir un outil pour l’analyse de l’image. [less ▲]

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See detailTree species and time since afforestation drive soil C and N mineralization on former cropland
Rahman, Md Masudur ULg; Bàrcena, Teresa G; Vesterdal, L

in Geoderma (2017), 305

Conversion from agriculture to forestry is considered a measure for mitigation of atmospheric CO2 but the impacts on soil C and N processes remain still unclear. We investigated heterotrophic respiration ... [more ▼]

Conversion from agriculture to forestry is considered a measure for mitigation of atmospheric CO2 but the impacts on soil C and N processes remain still unclear. We investigated heterotrophic respiration (RH), specific carbon mineralization (CMIN) and nitrogen mineralization (NMIN) in Norway spruce (Picea abies (Karst.) L.) and oak (Quercus robur L.) chronosequences on former cropland by laboratory incubation. The RH was estimated as the release of C per gram soil and CMIN as the release of C per gram of soil organic matter (SOM). Seven Norway spruce stands (16–44 years), eight oak stands (4–43 years), a cropland, a 35 years old permanent pasture and a 200-year-old oak-dominated forest were sampled (0–5 cm and 5–15 cm soil layers) in early spring. The SOM content gradually increased with stand age in 0–5 cm but remained the same in the 5–15 cm soil layer. The RH in the 0–5 cm layer gradually increased with time since afforestation in both tree species while there was no change in CMIN. In 5–15 cm, neither RH nor CMIN changed significantly after afforestation, but oak stands had significantly higher RH than Norway spruce. The NMIN and nitrification in 0–5 cm significantly increased with stand age and only nitrification was higher in oak. In 5–15 cm, only NMIN in oak increased with stand age, but both NMIN and nitrification were significantly higher in oak than spruce. Cropland RH, CMIN and NMIN rates were comparable to those found within the first decades of afforestation, whereas the 200-year-old forest and the pasture generally had RH and NMIN rates similar to the older chronosequence stands. We conclude that potential RH and soil N mineralization increased with time since afforestation and were tree species specific. Soil organic C stock gains observed in this area during the first 45 years after afforestation were not driven by decreased SOM decomposability, leaving increased litter C inputs as a more likely explanation. The lower CMIN in the 200-year-old forest suggests that future studies should include older forests to assess if the stability of C and the retention of N may increase in a longer term perspective. [less ▲]

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See detailIndexing grey multilingual literature in General Practice in the era of Semantic Web
Jamoulle, Marc ULg; Resnick, Melissa; Ittoo, Ashwin ULg et al

in The Grey Journal (2017, October 23)

voir abstract ci-dessous

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See detailConférence d'ouverture : Sartre, la Conférence de Rome, 1964
Cormann, Grégory ULg; Bourgault, Jean

Conference (2017, September 22)

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See detailComparative fire analysis of steel-concrete composite buildings designed following performance-based and U.S. prescriptive approaches
Elhami Khorasani, Negar; Fang, C.; Gernay, Thomas ULg

in Proceedings of the ASFE '17 Conference (2017, September 08)

Performance-based structural fire design provides a rational methodology for designing modern buildings with cost-effective solutions. However, in the United States, fire design still largely relies on ... [more ▼]

Performance-based structural fire design provides a rational methodology for designing modern buildings with cost-effective solutions. However, in the United States, fire design still largely relies on design at the component level using prescriptive approaches. With performance-based approaches, there is an opportunity to benefit from increased flexibility and reduced cost in the design, but these advantages need to be explicitly described and disseminated to promote this shift in paradigm. In this paper, a comparative analysis is conducted on multi-story steel-concrete buildings designed following performance-based and U.S. prescriptive approaches. The steel-concrete composite structure allows taking advantage of tensile membrane action in the slab during fire, and therefore removing the fire protection on secondary beam elements. The nonlinear finite element software SAFIR is used to model the behavior of the buildings under the standard ASTM fire and a natural fire determined using the two-zone fire model CFAST. The numerical simulations show that performance-based design can be used to achieve the required level of safety currently enforced in the U.S. prescriptive guidelines, while providing an opportunity for cost reduction in fire protection material. [less ▲]

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See detailA method for hybrid fire testing: Development, implementation and numerical application
Sauca, Ana ULg; Mergny, Elke ULg; Gernay, Thomas ULg et al

in Proceedings of ASFE'17 Conference (2017, September 08)

Hybrid Fire Testing (HFT) is a technique that allows assessing experimentally the fire performance of a structural element under real boundary conditions that capture the effect of the surrounding ... [more ▼]

Hybrid Fire Testing (HFT) is a technique that allows assessing experimentally the fire performance of a structural element under real boundary conditions that capture the effect of the surrounding structure. To enable HFT, there is a need for a method that is unconditionally stable, ensures equilibrium and compatibility at the interface and captures the global behaviour of the analysed structure. A few attempts at conducting HFT have been described in the literature, but it can be shown, based on the analytical study of a simple one degree-of-freedom elastic system, that the considered method was fundamentally unstable in certain configurations which depend on the relative stiffness between the two substructures, but which cannot be easily predicted in advance. In this paper, a new method is introduced to overcome the stability problem and it is shown through analytical developments and applicative examples that the stability of the new method does not depend on the stiffness ratio between the two substructures. The new method is applied in a virtual hybrid test on a 2D reinforced concrete beam part of a moment resisting frame, showing that stability, equilibrium and compatibility are ensured on the considered multiple degree-of-freedom system. Besides, the virtual HFT succeeds in reproducing the global behaviour of the analysed structure. The method development and implementation in a virtual (numerical) setting is described, the next step being its implementation in a real (laboratory) hybrid test. [less ▲]

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See detailEffect of upgrading concrete strength class on fire performance of reinforced concrete columns
Gernay, Thomas ULg; Peric, Vlado; Mihaylov, Boyan ULg et al

in Proceedings of ASFE'17 Conference (2017, September 07)

High strength concrete (HSC) provides several advantages over normal strength concrete (NSC) and is being used in multi-story buildings for reducing the dimensions of the columns sections and increasing ... [more ▼]

High strength concrete (HSC) provides several advantages over normal strength concrete (NSC) and is being used in multi-story buildings for reducing the dimensions of the columns sections and increasing the net marketable area. However, upgrading of concrete strength class in a building may affect the fire performance, due to higher rates of strength loss with temperature and higher susceptibility to spalling of HSC compared with NSC. Reduction of columns sections also leads to increased member slenderness and faster temperature increase in the section core. These detrimental effects are well known, but their impact on fire performance of structures has not been established in terms of comparative advantage between NSC and HSC. In other words, it is not clear whether the consideration of fire resistance limits the opportunities for use of HSC for reducing the dimensions of columns sections in multi-story buildings. This research aims to address this question by comparing the fire behaviour of reinforced concrete columns made of NSC and HSC using nonlinear finite element modelling. The evolution of load bearing capacity of the columns is established as a function of the fire exposure duration. A 15-story car park structure is adopted as a case study with alternative designs for the columns based on strength classes ranging from C30 to C90. Results show that, although the replacement of NSC by HSC accelerates the reduction rate of columns capacity under fire, the columns generally have significant reserves in resistance leading to sufficient fire resistance. This study gives an insight into the impact of replacing stocky sections in NSC by more slender sections in HSC on fire resistance rating for multi-story structures. [less ▲]

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See detailSensitivity of elevated temperature load carrying capacity of thin-walled steel members to local imperfections
Maraveas, Chrysantos ULg; Gernay, Thomas ULg; Franssen, Jean-Marc ULg

in Proceedings of ASFE'17 Conference (2017, September 07)

The local buckling capacity of fire exposed thin-walled steel cross sections is affected by the reduction in strength and stiffness due to elevated temperatures and by the amplitude of the initial local ... [more ▼]

The local buckling capacity of fire exposed thin-walled steel cross sections is affected by the reduction in strength and stiffness due to elevated temperatures and by the amplitude of the initial local imperfections. Several researchers have proposed design methods to calculate the capacity of these steel members at elevated temperatures, but they used different methodologies and different amplitude of local imperfections in the extensive numerical analyses that are typically at the base of these methods. This variability in hypotheses happens because there is no clear provision defining the local imperfection amplitude for fire design in the codes (European or US). EN 1993-1-5 proposes amplitude values of local imperfections for ambient temperature design, while EN 1090-2 defines a -different- maximum allowed size of fabrication tolerance during production. Meanwhile, other sizes of local imperfections have also been proposed in the literature, with values different than those from EN 1993-1-5 and EN 1090-2. This paper reviews the existing code provisions and compares the existing design models and their assumptions for thin-walled steel cross sections. Finite element analyses are then conducted on isolated steel plates at elevated temperatures to investigate the effect of local imperfections. Finally, specific amplitude of local imperfections is proposed for fire design of thin-walled steel members. [less ▲]

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See detailLocals in the Wasteland: The Non-Intended Side Effects of (In)Sensible Local Participatory Technology Development.
Parotte, Céline ULg

Conference (2017, September)

Implementing high-level radioactive wastes programs on a territory remain a sensitive step for nuclear waste management organizations. At this stage, the preferred solution of radioactive wastes programs ... [more ▼]

Implementing high-level radioactive wastes programs on a territory remain a sensitive step for nuclear waste management organizations. At this stage, the preferred solution of radioactive wastes programs (geological disposal) and their technological developments become highly visible and this is why the new instruments and strategies such as participatory technology development (PDT) have been adopted to tackle the territorial development of geological disposal technology. Considering the coproduction between territory and program (Jasanoff 2004), this presentation focuses on two siting processes of radioactive wastes programs, in France and in Canada to analyze the influence of in(sensible) local participatory technology development strategy and the influence of invited critics (Wynne 2007) on the industrial project. Our results show that frameworks of the participatory technology development have been designed very differently (with or without publics). Consequently, two undesirable, mostly non-intended side effects of information local committees (non) integration have appeared. In France, a closed PDT transformed invited critics as non-invited one. In Canada, a weak engagement of publics has occurred with an opened PDT. In both case, new socio-technical adjustments have occurred in those programs. [less ▲]

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See detailLa normalisation européenne après l’arrêt James Elliott Construction du 27 octobre 2016 : la Cour de justice de l’Union européenne a-t-elle élargi ses compétences d’interprétation ?
Van Cleynenbreugel, Pieter ULg; Demoulin, Iris ULg

in Revue de la Faculté de Droit de l'Université de Liège (2017), (2),

Malgré son importance pratique, le processus de normalisation européenne a jusqu’à présent été relativement épargné par la Cour de justice. Toutefois, dans son arrêt James Elliott Construction du 27 ... [more ▼]

Malgré son importance pratique, le processus de normalisation européenne a jusqu’à présent été relativement épargné par la Cour de justice. Toutefois, dans son arrêt James Elliott Construction du 27 octobre 2016, la Cour s’est penchée directement sur le statut juridique des normes techniques européennes. Confirmant que l’interprétation des normes techniques harmonisées, actes non contraignantes, peut être soumise à un examen jurisprudentiel, la Cour a assimilé ces normes adoptées par des organismes privés à des actes des institutions de l’Union européenne. Cet article analyse les impacts de cet arrêt sur le cadre institutionnel de la normalisation européenne. Une telle analyse permettra de conclure que la Cour a interprété ses compétences d’interprétation extensivement afin de rendre possible plus directe son implication dans cette matière. [less ▲]

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See detailCompositional gap at La Picada (CSVZ, Chile) results from critical cristallinity and compaction
Vander Auwera, Jacqueline ULg; Namur, Olivier ULg; Coumont, Valentin et al

Poster (2017, August 16)

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See detail3D thermal finite element analysis of laser cladding processed Ti-6Al-4V part with microstructural correlations
Tran, Hoang Son ULg; Tchuindjang, Jérôme Tchoufack ULg; Paydas, Hakan ULg et al

in Materials & Design (2017), 128

In this study, a 3D thermal model of laser cladding by powder injection applied to Ti-6Al-4V is developed. The manufactured part is made of a Ti-6Al-4V substrate on which successive layers of laser melted ... [more ▼]

In this study, a 3D thermal model of laser cladding by powder injection applied to Ti-6Al-4V is developed. The manufactured part is made of a Ti-6Al-4V substrate on which successive layers of laser melted powder are added, leading to a thick deposit. The computed temperature field and its time evolution are compared to experimental measurements. The temperature distribution in the substrate allows the prediction of the depths of the melt pool and the heat affected zone. Correlations between simulated thermal histories and the final microstructure in the thick deposit are established, leading to the enhancement of a dynamic shift of the critical transformation points due to high thermal rates during laser processing. The nature of the phases present within the deposit is discussed. [less ▲]

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See detailExergy analysis applied to performance of buildings in Europe
Sartor, Kevin ULg; Dewallef, Pierre ULg

in Energy and Buildings (2017), 148

Energy performance of buildings generally assesses the energy consumption of buildings such as heating, domestic heat water, ventilation systems, etc. However, this approach is based on the first law of ... [more ▼]

Energy performance of buildings generally assesses the energy consumption of buildings such as heating, domestic heat water, ventilation systems, etc. However, this approach is based on the first law of thermodynamics and considers only the quantity of energy used without considering its ‘quality’ and leads to a lack of information about the energy conversion processes. This is particularly true in the new low-energy buildings where sometimes high temperatures sources are used to meet low-temperature needs. The exergy analysis of a system, based on first and second thermodynamic laws, can be used to overcome this. In this work, it is proposed to compare the energy and the exergy consumption and the related CO2 emissions of several kinds of buildings to determine the best systems in terms of energy and exergy needs. The energy demand calculations are performed using the official software available in Belgium and some assumptions are implemented to consider the exergy approach. As exergy calculations require a reference state, some different climatic conditions are also investigated. Finally, some conclusions are discussed to rank the sources of energy and their related exergy losses. [less ▲]

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See detailBioinformatic Processing of Amplicon Sequencing Datasets
Sweetlove, Maxime; Obbels, Dagmar; Verleyen, Elie et al

in Kurmayer, Rainer; Sivonen, Kaarina; Wilmotte, Annick (Eds.) et al Molecular Tools for the Detection and Quantification of Toxigenic Cyanobacteria (2017)

Amplicon sequencing can be a very powerful approach for detecting toxic cyanobacteria or any other kind of microorganism during monitoring programs. However, owing to the huge size of next-generation ... [more ▼]

Amplicon sequencing can be a very powerful approach for detecting toxic cyanobacteria or any other kind of microorganism during monitoring programs. However, owing to the huge size of next-generation sequencing (NGS) datasets (up to several Gb), there is an obvious need for semi-automatic data processing and statistical analysis, as well as visualization of the patterns found. Importantly, raw NGS data contain errors, some of which are easily detected (e.g. too short or low-quality reads), while others remain hidden even after the most stringent quality controls (e.g. chimeras, contaminations, reads with large insertions or deletions, referred to as “indels”). As a consequence, NGS data need to be interpreted with caution, and bioinformatics analysis implementing poor error identification can easily lead to erroneous conclusions. Hence, a crucial step in the analysis of NGS data is the detection and removal of as many erroneous reads as possible. Moreover, bioinformatics involve additional preprocessing steps, including demultiplexing (i.e. grouping reads to samples according to the barcode sequence), deleting non-biological tags together with the adaptors and primer sequences, and removing chimeric sequences. In addition, the bioinformatics pipelines enable the quality-filtered sequences to be clustered into biologically relevant operational taxonomic units (OTUs), which form the basis of the statistical analysis, including the calculation of alpha- and beta-diversity. [less ▲]

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