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See detailEVALUATION OF FISH EXPOSURE TO POP-LIKE (ORGANOTIN) COMPOUNDS IN SEPETIBA BAY (RIO DE JANEIRO STATE, BRAZIL) THROUGH HEPATIC TOTAL TIN CONCENTRATIONS
Paiva, TC; Schilithz, PF; Bisi, TL et al

in Organohalogen Compounds (2016, August)

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See detailPhonological acquisition in CLIL- and non-CLIL education
Rasier, Laurent ULg

Conference (2016, August)

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See detailShaping (im)mobility in border camps: a case study of the transformation of Calais camps and its actors
Da Silva, Amanda Carolina ULg

Conference (2016, July 13)

This paper explores the transition of informal temporary camps on the French border to a sustainable state, and discusses how local policy decisions and non-state actors worked together for the ... [more ▼]

This paper explores the transition of informal temporary camps on the French border to a sustainable state, and discusses how local policy decisions and non-state actors worked together for the implementation of a semi-permanent exclusion system based on the refugee crisis. I observe this issue as a result of a securitization process. The securitization apparatus (speech acts and policies), produced the immobility of a group. In the other hand actors will emerge to produce mobility. When a situation is defined as a crisis, atypical actions can be employed to protect the «political community». I started from the assumption that dialectic relation between securitization and camps actors had a high impact on the projects of refugees, and so long in their mobility. This is a question of integration policies at the local level. I aim to highlight the local level relevance, where the integration is primarily implemented, and therefore local and regional context should matter as much as the national model for integration (Martiniello, 2013). In Calais, due to the lack of immigrants policies, civilians associations started to react and build informal camps, but due to recent "crisis" the Stat concentrated all refugees in a single camp, 6 kilometers from the city center, called bidonville. [less ▲]

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See detailOn the use of ROC curves in DIF simulation studies
Magis, David ULg; Tuerlinckx, Francis

Conference (2016, July 12)

Simulation studies are often used to compare methods to detect differential item functioning (DIF). However, comparing the performance of such methods can become complicated when the identification of DIF ... [more ▼]

Simulation studies are often used to compare methods to detect differential item functioning (DIF). However, comparing the performance of such methods can become complicated when the identification of DIF items relies on statistics based on pre-defined significance level or on pre-established cutoff values. DIF methods based on conceptually different approaches may therefore become incomparable in terms of summary DIF statistics such as false alarm rate or hit rate. The purpose of this talk is to overcome this analytic issue by introducing receiver operating characteristic (ROC) curves in this context. ROC curves allow for global comparison of methods’ performances by computing pairs of (false alarm, hit) rates and representing them on a common scatter plot. Several summary ROC statistics can be considered for further analysis. The application of the ROC curve methodology, together with its limitation and possible extensions, is illustrated by a simple simulation study that compares three score-based DIF methods (Mantel-Haenszel, standardization and Delta plot). [less ▲]

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See detailExamine the effects of two adjustments to the lz statistic
Riley, Barth; Magis, David ULg

Conference (2016, July 12)

Conformity to a known distribution and sensitivity to response aberrance are desirable properties of person-fit statistics. This simulation study examined the joint and independent effects of two ... [more ▼]

Conformity to a known distribution and sensitivity to response aberrance are desirable properties of person-fit statistics. This simulation study examined the joint and independent effects of two adjustments to the standardized log-likelihood statistic (lz): (1) correction of the negatively skewed distribution of lz (Snijders, 2001), and (2) improving the sensitivity of the statistic by employing more accurate estimates of item response probability using symmetric functions (Dimitrov and Smith, 2006). Data were simulated using three test lengths (10, 20, 30 items). Data containing misfitting response patterns were simulated using three aberrant response patterns (cheating, guessing, and inattentiveness), and three levels of aberrance (i.e., proportion of item responses affected by misfit; 10%, 30% and 50%). Data containing no simulated misfitting response patterns were also generated for each test length. Non-misfitting responses were generated using the dichotomous Rasch measurement model. For each combination of independent variables, a dataset was generated consisting of 5,000 simulees. Four fit statistics were compared: lz, lz* (Snijders adjustment), lzSYM (Dimitrov and Smith adjustment), and lzSYM* (both adjustments). Mean Type I error rates were ≤ 0.1 across all conditions. The lz* statistic produced the best control of Type I error, which was often below the nominal Type I error rate, whereas the empirical Type I error rate for the unadjusted lz statistic most closely approximated the nominal rate. In contrast, lzSYM and lzSYM* yielded empirical Type I error rates larger than the nominal rate, with the discrepancy being particularly pronounced as the length of the test decreased. As might be expected, power to detect misfitting response patterns increased with test length and with the percentage of misfitting response patterns in the sample. Both lzSYM and lzSYM* evidenced improved power in detecting misfitting response patterns compared to lz and lz*, particularly for guessing response patterns and/or on shorter (i.e., 10 item) tests. [less ▲]

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See detailOpen source programming: a new hope for psychometric research
Magis, David ULg

Conference (2016, July 12)

Current psychometric research is most often supported by computer software. New research perspectives often imply intensive simulation studies to validate the tested theories or hypotheses, and therefore ... [more ▼]

Current psychometric research is most often supported by computer software. New research perspectives often imply intensive simulation studies to validate the tested theories or hypotheses, and therefore require accurate, fast and stable implementation. To this regards, open source programming (such as in the R language) is a promising approach allowing for flexible implementation, data generation, replication of studies, and worldwide dissemination. The purpose of this talk is to illustrate how psychometrics and open source programming (with special emphasis on the R language) can interact and contribute to each other, by means of some selected examples. Several topics will be illustrated, among others: why open source programming is (to my opinion) as important as psychometric research; why we need for stable and complete implementation of psychometric and statistical routines for research purposes (for e.g., CAT); how accurate implementation of IRT routines can lead to unexpected theoretical results; why (and how) open source software can be valued as research output. Most examples will arise from the CAT framework and the R package catR for simulating CAT patterns. [less ▲]

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See detailA Novel Methodology for Hybrid Fire Testing
Sauca, Ana ULg; Gernay, Thomas ULg; Robert, Fabienne et al

in Proceedings of the 6th European Conference on Structural Control (2016, July 11)

This paper describes a novel methodology for conducting stable hybrid fire testing (HTF). During hybrid fire testing, only a part of the structure is tested in a furnace while the reminded structure is ... [more ▼]

This paper describes a novel methodology for conducting stable hybrid fire testing (HTF). During hybrid fire testing, only a part of the structure is tested in a furnace while the reminded structure is calculated separately, here by means of a predetermined matrix. Equilibrium and compatibility at the interface between the tested “physical substructure” and the “numerical substructure” is maintained throughout the test using a dedicated algorithm. The procedures developed so far are sensitive to the stiffness ratio between the physical and the numerical substructure and therefore they can be applied only in some cases. In fire field, the stiffness of the heated physical substructure may change dramatically and the resulting change in stiffness ratio can lead to instability during the test. To overcome this drawback, a methodology independent of the stiffness ratio has been developed, inspired from the Finite Element Tearing and Interconnecting (FETI) method, which has been originally developed for substructuring in numerical analyses. The novel methodology has been successfully applied to a hybrid fire test in a purely numerical environment, i.e. the physical substructure was also modelled numerically. It is shown that stability does not depend on the stiffness ratio and that equilibrium and compatibility can be consistently maintained at the interface during the fire. Finally, the ongoing experimental program aimed at employing and experimentally validating this methodology is described. [less ▲]

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See detailPerformance et Innovation en PME: une relation à questionner
Ajzen, Michel; Rondeaux, Giseline ULg; Pichault, François ULg et al

in Revue Internationale P.M.E. (2016), 29(2),

Noting that in management science, management policies would have all, the ultimate ambition of contributing to company performance and the innovative capacity of a company would be a sine qua non of this ... [more ▼]

Noting that in management science, management policies would have all, the ultimate ambition of contributing to company performance and the innovative capacity of a company would be a sine qua non of this performance, this article shows that (if) these two concepts refer to disparate content; (ii) the performance is primarily measured by distanced indicators (financial); (iii) the nature of the interdependence between innovation and performance is not unequivocal. Considering the weight of contextual variables, we show the interest to adopt a broader vision of concepts of innovation and performance in SMEs, capitalizing on the diversity of performance and innovation characterizations, and adopting an agnostic approach establishing no a priori link between them. This article proposes to broaden the concepts of innovation and performance by mobilizing indicators specific to SMEs and outlines a methodology to measure and weigh them as well as to provide researchers with tools to better understand the interactions between these variables. In doing so, we contribute to a critical approach of de-naturalization to emancipate SMEs and, more broadly, public and regulatory authorities, from narrow performative standards. [less ▲]

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See detailMulti-species measurements of nitrogen isotopic composition r 1 eveal the spatial constraints and 2 biological drivers of ammonium attenuation across a highly contaminated groundwater system
Wells, Naomi S.; Hakoun, Vivien ULg; Brouyère, Serge ULg et al

in Water Research (2016), 98

Groundwater under industrial sites is characterised by heterogeneous chemical mixtures, making it difficult to assess the fate and transport of individual contaminants. Quantifying the in-situ biological ... [more ▼]

Groundwater under industrial sites is characterised by heterogeneous chemical mixtures, making it difficult to assess the fate and transport of individual contaminants. Quantifying the in-situ biological removal (attenuation) of nitrogen (N) is particularly difficult due to its reactivity and ubiquity. Here a multi-isotope approach is developed to distinguish N sources and sinks within groundwater affected by complex industrial pollution. Samples were collected from 70 wells across the two aquifers underlying a historic industrial area in Belgium. Below the industrial site the groundwater contained up to 1000 mg Nl-1 ammonium (NH4 +) and 300 mg N l-1 nitrate (NO3-), while downgradient concentrations decreased to ~1 mg l-1 DIN ([DIN] = [NH4+-N] + [NO3--N] + [NO2--N]). Mean δ1534 N-DIN increased from ~2‰ to +20‰ over this flow path, broadly confirming that biological N attenuation drove the measured concentration decrease. Multi-variate analysis of water chemistry identified two distinct NH4+ sources (δ15N-NH4+ from -14‰ and +5‰) within the contaminated zone of both aquifers. Nitrate dual isotopes co-varied (δ15 N: -3‰ - +60‰; δ18O: 0‰ - +50‰) within the range expected for coupled nitrification and denitrification of the identified sources. The fact that δ15N-NO2- values were 50‰ to 20‰ less than δ15N-NH4+ values in 40 the majority of wells confirmed that nitrification controlled N turnover across the site. However, the fact that δ15N-NO2- was greater than δ15N-NH4+ in wells with the highest [NH4+] shows that an autotrophic NO2- reduction pathway (anaerobic NH4+ oxidation or nitrifier-denitrification) drove N attenuation closest to the contaminant plume. This direct empirical evidence that both autotrophic and heterotrophic biogeochemical processes drive N attenuation in contaminated aquifers demonstrates the power of multiple N isotopes to untangle N cycling in highly complex systems. [less ▲]

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See detailA simple calibration approach based on film-casting for confocal Raman microscopy to support the development of a Hot-Melt Extrusion process
Netchacovitch, Lauranne ULg; Thiry, Justine ULg; De Bleye, Charlotte ULg et al

in Talanta (2016), 154

When developing a new formulation, the development, calibration and validation steps of analytical methods based on vibrational spectroscopy are time-consuming. For each new formulation, real samples must ... [more ▼]

When developing a new formulation, the development, calibration and validation steps of analytical methods based on vibrational spectroscopy are time-consuming. For each new formulation, real samples must be produced and a “reference method” must be used in order to determine the Active Pharmaceutical Ingredient (API) content of each sample. To circumvent this issue, the paper presents a simple approach based on the film-casting technique used as a calibration tool in the framework of hot-melt extrusion process. Confocal Raman microscopic method was successfully validated for the determination of itraconazole content in film-casting samples. Then, hot-melt extrusion was carried out to produce real samples in order to confront the results obtained with confocal Raman microscopy and Ultra High Performance Liquid Chromatography (UHPLC). The agreement between both methods was demonstrated using a comparison study based on the Bland and Altman’s plot. [less ▲]

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See detailIs there an alphabet of Moroccan cuisine? Notes on the materiality of cooking and eating.
Mescoli, Elsa ULg

Conference (2016, July)

Short Abstract Stemming from the ethnographic material collected during an eighteen months fieldwork conducted among a group Moroccan of women in Milan to study their food practices, this paper focuses on ... [more ▼]

Short Abstract Stemming from the ethnographic material collected during an eighteen months fieldwork conducted among a group Moroccan of women in Milan to study their food practices, this paper focuses on the materiality of cooking and eating through adopting a micro-structural approach. Long Abstract Inspired by the work of Lévi-Strauss (1964) aimed at identifying the relationships of mutual intelligibility underlying some social and cultural facts such as the treatment of food, this paper will focus on the materiality of cooking and eating through adopting a micro-structural approach. The ethnographic data collected during an eighteen months fieldwork conducted among a group of Moroccan women in Milan to study their cooking and eating habits will be analysed by paying particular attention to the practices and elements that made the "alphabet" of Moroccan cuisine. This means that, if we considered dishes as complex sentences which can be deciphered by people that share a same language, we could try to identify the littlest components that made them happen. Which norms regulated the combination of ingredients? Which ways of cooking described this food culture? Which gestures and embodied knowledge seemed essential to give an intelligible cultural connotation to the cooking and eating of food? Which variations were admitted? The analysis of the actors' discourses and practices will show how Lévi-Strauss approach and model to the study of foodways can meet a material culture approach and still be relevant nowadays. [less ▲]

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See detailFrom nature to culture? Lévi-Strauss' legacy and the study of contemporary foodways
Mescoli, Elsa ULg; Graf, Katharina

Conference (2016, July)

n the first volume of his Mythologiques, entitled The Raw and the Cooked, Claude Lévi-Strauss argued that the preparation of food is a form of language that reveals a society's structure. For Lévi-Strauss ... [more ▼]

n the first volume of his Mythologiques, entitled The Raw and the Cooked, Claude Lévi-Strauss argued that the preparation of food is a form of language that reveals a society's structure. For Lévi-Strauss, the so-called culinary triangle of the raw, the rotten and the cooked represents a semantic field within which the various forms of transformation of food from nature into culture play a key role. Since Lévi-Strauss, following extensive changes to food production, preparation and consumption, the notion of cooking has become ever more diversified, and became increasingly contentious. Yet, the multiple ways of combining and processing ingredients still give social and cultural meanings to food and trigger the creation of sociabilities and belongings through its own destruction (Gell 1986). This panel aims to explore Levi-Strauss' legacy and evaluate its usefulness in today's context from different angles, ranging from domestic food preparation to industrial production and global circulations of food. To what extent can this concept still provide an interpretative framework of topical food issues? Which contemporary myths does it shed light on? How could it be deployed to read the history of food and link it to contemporary questions? This panel welcomes papers on the history of food preparation, contemporary food preparation, including debates in professional and multimedia circles, various forms of food production and the possible transformation of food within globalised food markets. Although mobilizing a classic anthropological theory, this panel aims to be interdisciplinary and to present a diverse range of analytical perspectives. [less ▲]

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See detailDe l’activation à la précarité : analyse de deux dispositifs d’intervention sociale
Gérard, Julie ULg; Vrancken, Didier ULg

Conference (2016, July)

La lutte contre le chômage de longue durée et l’exclusion sociale par un retour à l’emploi représentent des enjeux essentiels des politiques actives du marché du travail. C’est pourquoi, cette ... [more ▼]

La lutte contre le chômage de longue durée et l’exclusion sociale par un retour à l’emploi représentent des enjeux essentiels des politiques actives du marché du travail. C’est pourquoi, cette communication s’intéresse aux effets de l’intervention sociale sur les demandeurs d’emploi à partir de l’analyse de deux dispositifs d’activation situés en Belgique francophone : une Entreprise de Formation par le Travail et une agence de Titres-Services. Au moyen d’une étude qualitative reposant sur une soixantaine d’observations de situations d’interactions réalisée entre bénéficiaires et « travailleurs du social » (consultant, assistant social, formateur, etc.) et, d’une quarantaine d’entretiens semi-directifs, nous rendrons compte de l’action de ces deux dispositifs dans le domaine de l’insertion-socioprofessionnelle. Nous illustrerons combien, par l’articulation de politiques d’emploi à vocation universelle et de politiques particularistes destinées aux personnes les plus fragiles, ces dispositifs génèrent de véritables trappes à précarité. À terme, nous montrerons combien le maintien de ces dernières soulève la question du développement progressif d’un nouveau régime de protections, opérant a minima, voire par défaut, auprès des publics peu qualifiés face à la menace sourde que font peser le marché noir et, plus largement, l’informalité du travail. [less ▲]

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See detailDisrupted interaction between self and memory in patients with Alzheimer’s disease
Genon, Sarah ULg; Salmon, Eric ULg; Collette, Fabienne ULg et al

Conference (2016, July)

In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship ... [more ▼]

In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship can be disrupted. This was evidenced by impaired SRE and SRRE in AD for recognition of adjectives previously judged for self-relevance, as well as recall of names of people previously linked to the self. For both materials, a qualitative impairment of the recollective experience for the self-related items was also observed in AD. A neuroimaging approach suggested that reduced SRE is related to decreased grey matter volume in the lateral prefrontal cortex (lPFC). Thus, retrieval of recent self-related memories is impaired in relation to altered high-order processes in lPFC in AD. [less ▲]

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See detailHolocene paleoclimate reconstructions from belgian continental archives
Allan, Mohammed ULg; VERHEYDEN, sophie; CRUCIFIX, Michel et al

Poster (2016, June 28)

Speleothems and peatbogs presented in Belgium are interesting archives for atmospheric pollution record and climate variability. Both archives are reliable continental environmental archives of high ... [more ▼]

Speleothems and peatbogs presented in Belgium are interesting archives for atmospheric pollution record and climate variability. Both archives are reliable continental environmental archives of high interest due to their dating possibilities and their possibility to preserve multi-proxy records of environmental and climatic dynamics. Combining studies on speleothems and peatbogs from the same area will provide an age-constrained reconstruction of climatic variability at annual resolution for key intervals of the Holocene. The reconstructed precipitation and temperature curves in NW European settings, as proposed in HOPES, are essential to better constrain the Northern Hemisphere climatic record and to test climate models. Our strategy is derived from a comparative study of two continental archives speleothems and peatbogs. Time series of elemental and stable isotope geochemistry will be established for the 2 archives. For peatbog, the reconstructions of temperature (derived from stable C and O isotope), precipitation (derived from humification) and dust flux (from elementary geochemical signature) would track climate changes with subdecadal resolution. As an innovative part, Laser Ablation analyse of elemental geochemistry on impregnated peat section will allow to reach an annual resolution in the dust flux. For speleothems, records of temperature (derived from oxygen and carbon isotopic composition of calcite) and effective rainfall (derived from geochemical ratios) would reach a seasonal resolution. [less ▲]

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See detailMonitoring partnership networks- A graph theory approach
Faraz, Alireza ULg; Treiblmaier, Horst; Gerschberger, Markus

Conference (2016, June 17)

Recently, companies are forming strong relationships with their strategic suppliers and customers in order to maximize their profit in the global market. Such a partnership or strategic alliance is based ... [more ▼]

Recently, companies are forming strong relationships with their strategic suppliers and customers in order to maximize their profit in the global market. Such a partnership or strategic alliance is based on the mutual needs of both parties. A partnership network is formed by different strategic firms (e.g., suppliers, manufacturers, distributors, retailers) who intend to establish strong relationships together but without losing their ownership, power and control on the firm. For example, if supplier X has a strong relationship with customer Y and Y has a strong relationship with supplier Z, then X, Y and Z can form a partnership network with three nodes (X, Y and Z) and two edges (X ->Y and Z->Y). In this paper, we develop a statistical methods to study the normal behaviour of partnership networks. We furthermore develop a methodology that will help diagnose the nature of identified unusual network behavior. [less ▲]

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See detailConversion of visual post fire measurements into fire severity with the aid of thermo-plastic analysis for retrofitting
Molkens, Tom; Gernay, Thomas ULg; Van Coile, Ruben

in Proceedings of the 9th International Conference on Structures in Fire (2016, June 09)

At Koksijde in Belgium a severe fire took place in an apartment building in 2015, resulting in the death of a young man and visible structural damage to four balconies. Following the fire, experts were ... [more ▼]

At Koksijde in Belgium a severe fire took place in an apartment building in 2015, resulting in the death of a young man and visible structural damage to four balconies. Following the fire, experts were mandated to assess the damage and the need for structural repair. They estimated that the balconies had to be refurbished but that there were no other structural elements affected, in particular the slab inside the apartment could be left in place with only a surface treatment and new plaster finishing. However, the floor slab in the apartment located above the fire apartment exhibited several visual indications that the fire could have had a structural impact, such as residual deformations and cracks in the tiles. This paper presents a methodology to infer the fire severity based on post-fire measurements and non-linear thermo-plastic numerical simulations. Finally, knowing the fire severity, its effect on the structure is evaluated and a reliability-based assessment is made of the residual load bearing capacity of the slab. [less ▲]

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See detailCritical parameters in deriving fire fragility functions for steel gravity frames
Gernay, Thomas ULg; Elhami Khorasani, Negar; Garlock, Maria

in Proceedings of the 9th International Conference on Structures in Fire (2016, June 08)

Fire fragility functions can be used to characterize the probabilistic vulnerability of buildings to fire in the context of urban resilience assessment. A methodology has been proposed to develop such ... [more ▼]

Fire fragility functions can be used to characterize the probabilistic vulnerability of buildings to fire in the context of urban resilience assessment. A methodology has been proposed to develop such functions for multi-story steel buildings. However, a large number of parameters with uncertainties play a role in the process of constructing the fragility functions. The goal of this research is to identify the critical parameters that most affect the global fire safety by investigating the sensitivity of the fragility functions to different input parameters. Sensitivity in parameters affecting the fire model, the heat transfer process and the thermo-mechanical response is examined. The effects of different design assumptions at the system level are also studied. The presented approach is useful for selecting the prevailing parameters in a fire reliability analysis and it provides important information for modeling tools that can be used to evaluate resilience for fire scenarios. [less ▲]

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