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See detailCollective vortex behaviors: diversity, proximate, and ultimate causes of circular animal group movements
Delcourt, Johann ULg; Bode, W.F. Nikolaï; Denoël, Mathieu ULg

in Quarterly Review of Biology (in press)

Ant mill, caterpillar circle, bat doughnut, amphibian vortex, duck swirl, and fish torus are different names for rotating circular animal formations, where individuals turn around a common center. These ... [more ▼]

Ant mill, caterpillar circle, bat doughnut, amphibian vortex, duck swirl, and fish torus are different names for rotating circular animal formations, where individuals turn around a common center. These “collective vortex behaviors” occur at different group sizes from pairs to several million individuals and have been reported in a large number of organisms, from bacteria to vertebrates, including humans. However, to date, no comprehensive review and synthesis of the literature on vortex behaviors has been conducted. Here, we review the state of the art of the proximate and ultimate causes of vortex behaviors. The ubiquity of this behavioral phenomenon could suggest common causes or fundamental underlying principles across contexts. However, we find that a variety of proximate mechanisms give rise to vortex behaviors. We highlight the potential benefits of collective vortex behaviors to individuals involved in them. For example, in some species, vortices increase feeding efficiency and could give protection against predators. It has also been argued that vortices could improve collective decision making and information transfer. We highlight gaps in our understanding of these ubiquitous behavioral phenomena and discuss future directions for research in vortex studies. [less ▲]

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See detailTeletê peut-elle être déesse ? Note épigraphique (SEG 50, 168)
Pirenne-Delforge, Vinciane ULg

in Mètis : Revue d'Anthropologie du Monde Grec Ancien : Philologie, Histoire, Archéologie (in press)

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See detailPhenotypic variability in bioprocessing conditions can be tracked on the basis of on-line flow cytometry and fits to a scaling law
Baert, Jonathan ULg; Kinet, Romain ULg; Brognaux, Alison ULg et al

in Biotechnology Journal (in press)

Noise in gene and protein expression is a major cause for bioprocess deviation. However, this phenomenon has been only scarcely considered in real bioprocessing conditions. In this work, a scaling-law ... [more ▼]

Noise in gene and protein expression is a major cause for bioprocess deviation. However, this phenomenon has been only scarcely considered in real bioprocessing conditions. In this work, a scaling-law derived from a genome-scale studies based on GFP reporter systems has been calibrated to an on-line flow cytometry device, allowing thus to get an insight at the level of promoter activity and associated noise during a whole microbial culture carried out in bioreactor. We show that most of the GFP reporter systems investigated and thus corresponding genes could be included inside the area covered by the scaling-law. The experimental results suggest that this scaling-law could be used to predict the dynamics of promoter activity, as well as the associated noise, in bioprocessing conditions. The knowledge acquired throughout this work could be used for the design of more robust expression systems. [less ▲]

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See detailDifferential effects of context on psychomotor sensitization to ethanol and cocaine
Didone, Vincent ULg; Quoilin, Caroline; Dieupart, Julie et al

in Behavioural Pharmacology (in press)

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See detailSustaining Inter-Organizational Relationships across Institutional Logics and Power Asymmetries: the Case of Fair Trade
Nicholls, Alex; Huybrechts, Benjamin ULg

in Journal of Business Ethics (in press)

In Fair Trade (FT), as well as in other ‘mixed-form’ fields (Becchetti & Huybrechts 2008; Marwell & McInerney 2005), non-profit organizations and social enterprises have been partnering with large ... [more ▼]

In Fair Trade (FT), as well as in other ‘mixed-form’ fields (Becchetti & Huybrechts 2008; Marwell & McInerney 2005), non-profit organizations and social enterprises have been partnering with large corporations over long time periods despite the presence of conditions that might be expected to destabilize such relationships. These conditions include striking differences in size, economic power, and organizational goals or ‘logics’. Given these asymmetries, the collaborations are typically seen as problematic and temporary because the stronger party (the corporation) will impose its (market) logics upon the weaker one (the social enterprise), leading to either instrumentalizing and corrupting the latter or to the breakdown of the collaboration. Whilst some of the literature on FT and other market-oriented social movements has tended to depict corporate participation as a threat to the original goals of the social movement and to the integrity of partnering social enterprises (e.g. Fridell et al. 2008; Reed 2009), there is evidence of a set of social enterprise-corporate relationships that persist over time and cannot be simply summarized as dominated by the sole corporate, market logic. These examples illustrate the emergence of new working relationships across the conventional divides between distinct sectors – the public, private, and civil society – that offer new approaches to managing power asymmetries and apparently conflicting logics – typically, in FT and more generally in social entrepreneurship, market and social justice/welfare logics (Battilana & Lee 2014; Defourny & Nyssens 2006; Huybrechts & Nicholls 2012; Smith et al. forthcoming). This leads to the following research question: Under what conditions can inter-organizational relationships emerge and be sustained despite power asymmetries and the presence of distinct, potentially conflicting, institutional logics? The analysis in this paper aims to extend theory by providing an alternative to more deterministic analyses of inter-organizational relationships that suggest that the more powerful actor will always impose its logics upon the less powerful organization thus undermining the persistence of the relationship over time. In the process, this research adds a new construct to existing theory around the resolution of conflict in institutional logics by suggesting that dynamic persistence is also evident in contrast to examples of conflict resolution through dominance, compromise, hybridization, synthesis, or relationship breakdown. Based on the analysis of the relationships between commercial buyers and FTOs, initially embodying market and social justice logics respectively, this paper proposes a set of key conditions under which dynamic persistence can be observed even in the presence of power asymmetries. [less ▲]

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See detail“How are you Vulnerable?”: Using Participation for Vulnerability Analysis in Emergency Planning
Rossignol, Nicolas ULg; Turcanu, Catrinel; Fallon, Catherine ULg et al

in Journal of Risk Research (in press)

Scientists in many fields of research have developed models, theories and concepts attempting to grasp and manage dangers that are often difficult to imagine. Among the different perspectives, the Science ... [more ▼]

Scientists in many fields of research have developed models, theories and concepts attempting to grasp and manage dangers that are often difficult to imagine. Among the different perspectives, the Science and Technology Studies (STS) Vulnerability Approach seems very promising. Relying on a constructivist paradigm, it is based on an inductive collection and analysis of a wide range of factors, with a particular focus on cultural factors and actual day-to-day practices. In this paper, we present the roots of this approach and we display findings based on three case studies exploring emergency planning in three different contexts (a city near a SEVESO plant, a school near a nuclear plant, and a city confronted to multiple catastrophic scenarios). The cases studies were realized by conducting three Focus Groups with different types of stakeholders (citizens, teachers, firemen, decision makers, etc.). After presenting the results of the case studies, we discuss how stakeholders’ participation can inform such type of vulnerability analysis in the context of emergency planning. We argue that participation fosters a deep understanding of actual safety governance practices which allows innovative results to emerge as well as it initiates a learning process among the participants. It contributes to questioning the relations between decision-makers, experts and citizens. It has the potential of bypassing the positivist and quantitative rationale of safety, and thus, of redefining the vulnerability governance. As a conclusion, we question the role of such STS vulnerability approach within the actual vulnerability governance. [less ▲]

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See detailRéduire l’altérité au travers des processus de traduction et de représentation
Leclercq, Bruno ULg; Smette, Bernard ULg

in Doctorales. Revue LLA-SHS de Montpellier (in press)

WVO Quine questions the « myth » of an ideal realm of shared meanings which every national language would express in its own way. Against the hope of transparent translations, he insists on the necessity ... [more ▼]

WVO Quine questions the « myth » of an ideal realm of shared meanings which every national language would express in its own way. Against the hope of transparent translations, he insists on the necessity for building equivalences from one language to another through a strategy of reducing the differences in rationality among nations as much as possible. According to Quine, otherness is not insuperable impediment to meeting/encounter and mutual understanding ; by throwing our conceptual schemes on the other communities’ uses/practices – which of course involves some symbolic violence – gaps can always been narrowed. Similarly E. Laclau questions the traditional conception of political representation, which is seen as the transparent process of transmitting someone’s will or interests on another level. For this ideal conception of representation, Laclau substitutes a pragmatic conception which takes in account the irreducible gap between the actors as well as the constitutive opacity of the process of representation : the subject’s will is constituted within the process of representation and through the representative’s productive role. In order to be transposed at the decision-making level, the subject’s interests must be translated by the representative as well as be negotiated with the other represented interests. This implies that the initial will undergoes some identity transformations. [less ▲]

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See detailThe transition to conservation agriculture : an insularization process towards sustainability
Vankeerberghen, Audrey ULg; Stassart, Pierre M ULg; Dannevoye, Bastien ULg

in International Journal of Agricultural Sustainability (in press)

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See detailHepatoprotective and anti-diabetic activities of Fraxinus angustifoliaVahl extracts in animal models: Characterization by HPLC analysis
Medjahed, Zineb; Atmani-Kilani, Dina; Fauconnier, Marie-Laure ULg et al

in Turkish Journal of Medical Sciences (in press)

Background and aim: The present study was designed to explore anti-diabetic and hepato-protective potentials of Fraxinus angustifolia leaf (FAL) and bark (FAB) extracts in vivo.

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See detailHenry Flynt : Catalogue des oeuvres
Levaux, Christophe ULg

in Revue et Corrigée (in press), 109

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See detailRelative Ease in Creating Detailed Orthographic Representations Contrasted with Severe Difficulties to Maintain Them in Long-term Memory Among Dyslexic Children
Binamé, Florence ULg; Poncelet, Martine ULg

in Dyslexia (in press)

Most research into orthographic learning abilities has been conducted in English with typically developing children using reading-based tasks. In the present study, we examined the abilities of French ... [more ▼]

Most research into orthographic learning abilities has been conducted in English with typically developing children using reading-based tasks. In the present study, we examined the abilities of French-speaking children with dyslexia to create novel orthographic representations for subsequent use in spelling and to maintain them in long-term memory. Their performance was compared with that of chronological age (CA)-matched and reading age (RA)-matched control children. We used an experimental task designed to provide optimal learning conditions (i.e. 10 spelling practice trials) ensuring the short-term acquisition of the spelling of the target orthographic word forms. After a 1-week delay, the long-term retention of the targets was assessed by a spelling post-test. Analysis of the results revealed that, in the short term, children with dyslexia learned the novel orthographic word forms well, only differing from both CA and RA controls on the initial decoding of the targets and from CA controls on the first two practice trials. In contrast, a dramatic drop was observed in their long-term retention relative to CA and RA controls. These results support the suggestion of the self-teaching hypothesis (Share, 1995) that initial errors in the decoding and spelling of unfamiliar words may hinder the establishment of fully specified novel orthographic representations. [less ▲]

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See detailCarrying capacity of stainless steel columns in the low slenderness range.
Rossi, Barbara ULg; Rasmussen, Kim J.R.

in Journal of Structural Engineering (in press)

The strength of thin-walled stainless steel columns has been investigated extensively over the past few years. In European standards, the concept of section classification for determining the cross ... [more ▼]

The strength of thin-walled stainless steel columns has been investigated extensively over the past few years. In European standards, the concept of section classification for determining the cross-section capacity is used. In this system, for Class 4 cross-sections, the Effective Width Method (EWM) must be used to account for the effect of local buckling. Because of the complexity and limitations of this method, other methods have been developed, such as the Direct Strength Method (DSM) for cold-formed thin-walled profiles and the Continuous Strength Method (CSM), initially established for members made of nonlinear metallic materials. In the CSM, to take advantage of strain hardening, a deformation-based design approach employing a continuous relationship between the cross-sectional slenderness and the cross-sectional deformation capacity is used. To a large extent, the CSM yield accurate predictions, especially in the low slenderness range where the current DSM design procedures for members submitted to pure compression tends to produce conservative predictions, for materials with pronounced strain hardening such as stainless steel alloys. The present paper presents an extension of the traditional DSM which provides accurate design strength predictions in the low slenderness range for stainless steel thin-walled section columns failing by distortional, local and overall buckling. It contains practical information concerning the reference experimental data and draws conclusions about the justification of the proposed analytical formula. The paper is divided into three main parts: the description of the database, the establishment of the design model and a reliability analysis of the method. [less ▲]

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See detailThin film superconducting shields
Claassen, John; Osofsky, Michael; Namburi, Devendra et al

in IEEE Transactions on Applied Superconductivity (in press)

To date, magnetic shields utilizing high-temperature superconductor materials mostly comprise bulk materials, usually shaped into a cylinder and then heat treated. We analyze the potential of thin-film ... [more ▼]

To date, magnetic shields utilizing high-temperature superconductor materials mostly comprise bulk materials, usually shaped into a cylinder and then heat treated. We analyze the potential of thin-film technology, whereby a layer of superconductor is deposited on a substrate, to fabricate magnetic shields. Films deposited on a curved surface are inevitably granular, leading to reduced critical current density compared with crystalline films. This limits the maximum field that can be screened. Granular films also have an enhanced penetration depth compared with the bulk value, which determines the maximum possible screening at applied fields below the maximum.We demonstrate the utility of a mutual inductancemeasurement to evaluate small flat test samples of a granular film for their potential as a shielding material in a more complex geometry. Thismeasurement predicts both themaximum magnetic field that can be screened and the residual leakage at fields below the maximum. The tested film was produced by the Electrophoretic deposition of YBCO on a silver substrate. The maximum screening field was comparable with that obtained for a similar film on a cylindrical substrate. We also show comparable results from a crystalline YBCO film. [less ▲]

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See detailConcentration, Activity and Biochemical Characterization of Myeloperoxidase in Fresh and Post-thaw equine semen and their Implication on Freezability
Ponthier, Jérôme ULg; Franck, Thierry ULg; Parrilla Hernandez, Sonia ULg et al

in Reproduction in Domestic Animals (in press)

Myeloperoxidase (MPO) is a pro-oxidant enzyme associated with decreased motility in thawed equine semen. This study aimed to describe MPO concentration, activity and subunits in raw and thawed semen and ... [more ▼]

Myeloperoxidase (MPO) is a pro-oxidant enzyme associated with decreased motility in thawed equine semen. This study aimed to describe MPO concentration, activity and subunits in raw and thawed semen and to correlate these data with motilities in raw and thawed semen. Semen samples from five stallions were collected four times. Motilities were assessed in raw and thawed semen. MPO assays were performed in raw seminal plasma, raw sperm-rich pellet and thawed semen. Total and active MPO concentrations were, respectively, assayed by enzyme-linked immunosorbent assay and specific immunological extraction followed by enzymatic detection. MPO subunits present in semen were characterized by Western 3 blot. Purified active MPO was added in PBS and freezing extender to control its activity during freezing procedure. Differences between medians were determined using Kruskal– Wallis test, and correlations were determined using Spearman’s test for nonparametric data. Active MPO concentration was low in seminal plasma and thawed semen, but high in pellet (p = 0.0058), as the opposite relation was observed for total MPO concentration (p < 0.0001). In seminal plasma and post- thaw semen, inactive 86-kDa MPO precursor was mainly observed. Purified MPO activity was decreased in the extender (p = 0.0286). MPO activity in pellet was highly correlated with thawed progressive motility (r = 􏰑0.5576, p = 0.0086). Inac- tive MPO precursor and unknown low molecular weight inactive MPO precursor subunits explain low MPO activity in semen. Major MPO activity was observed in pellet, and post- thaw loss of activity is partially explained by MPO inactiva- tion in extender. Thawed semen motility was negatively correlated with MPO activity in pellet, becoming a potential freezability predictor. [less ▲]

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See detailThe impact of dissolved organic carbon and bacterial respiration on pCO2 in experimental sea ice
Zhou, Jiayun; Kotovitch, Marie ULg; Kaartokallio, H. et al

in Progress in Oceanography (in press)

Previous observations have shown that the partial pressure of carbon dioxide (pCO2) in sea ice brines is generally higher in Arctic sea ice compared to those from the Antarctic sea ice, especially in ... [more ▼]

Previous observations have shown that the partial pressure of carbon dioxide (pCO2) in sea ice brines is generally higher in Arctic sea ice compared to those from the Antarctic sea ice, especially in winter and early spring. We hypothesized that these differences result from the higher dissolved organic carbon (DOC) content in Arctic seawater: Higher concentrations of DOC in seawater would be reflected in a greater DOC incorporation into sea ice, enhancing bacterial respiration, which in turn would increase the pCO2 in the ice. To verify this hypothesis, we performed an experiment using two series of mesocosms: one was filled with seawater (SW) and the other one with seawater with an addition of filtered humic-rich river water (SWR). The addition of river water increased the DOC concentration of the water from a median of 142 µmol L-1 in SW to 249 µmol L-1 in SWR. Sea ice was grown in these mesocosms under the same physical conditions over 19 days. Microalgae and protists were absent, and only bacterial activity has been detected. We measured the DOC concentration, bacterial respiration, total alkalinity and pCO2 in sea ice and the underlying seawater, and we calculated the changes in dissolved inorganic carbon (DIC) in both media. We found that bacterial respiration in ice was higher in SWR: median bacterial respiration was 25 nmol C L-1 h-1 compared to 10 nmol C L-1 h-1 in SW. pCO2 in ice was also higher in SWR with a median of 430 ppm compared to 356 ppm in SW. However, the differences in pCO2 were larger within the ice interiors than at the surfaces or the bottom layers of the ice, where exchanges at the air-ice and ice-water interfaces might have reduced the differences. In addition, we used a model to simulate the differences of pCO2 and DIC based on bacterial respiration. The model simulations support the experimental findings and further suggest that bacterial growth efficiency in the ice might be 0.15-0.2. It is thus credible that the higher pCO2 in Arctic sea ice brines compared with those from the Antarctic sea ice were due to an elevated bacterial respiration, sustained by higher riverine DOC loads. These conclusions should hold for locations and time frames when bacterial activity is relatively dominant compared to algal activity, considering our experimental conditions. [less ▲]

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See detailMetal binding to the N-terminal cytoplasmic domain of the PIB ATPase HMA4 is required for metal transport in Arabidopsis.
Laurent, Clémentine ULg; Lekeux, Gilles ULg; Ukuwela, Ashwinie A et al

in Plant Molecular Biology (in press)

PIB ATPases are metal cation pumps that transport metals across membranes. These proteins possess N- and C-terminal cytoplasmic extensions that contain Cys- and His-rich high affinity metal binding ... [more ▼]

PIB ATPases are metal cation pumps that transport metals across membranes. These proteins possess N- and C-terminal cytoplasmic extensions that contain Cys- and His-rich high affinity metal binding domains, which may be involved in metal sensing, metal ion selectivity and/or in regulation of the pump activity. The PIB ATPase HMA4 (Heavy Metal ATPase 4) plays a central role in metal homeostasis in Arabidopsis thaliana and has a key function in zinc and cadmium hypertolerance and hyperaccumulation in the extremophile plant species Arabidopsis halleri. Here, we examined the function and structure of the N-terminal cytoplasmic metal-binding domain of HMA4. We mutagenized a conserved CCTSE metal-binding motif in the domain and assessed the impact of the mutations on protein function and localization in planta, on metal-binding properties in vitro and on protein structure by Nuclear Magnetic Resonance spectroscopy. The two Cys residues of the motif are essential for the function, but not for localization, of HMA4 in planta, whereas the Glu residue is important but not essential. These residues also determine zinc coordination and affinity. Zinc binding to the N-terminal domain is thus crucial for HMA4 protein function, whereas it is not required to maintain the protein structure. Altogether, combining in vivo and in vitro approaches in our study provides insights towards the molecular understanding of metal transport and specificity of metal P-type ATPases. [less ▲]

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See detailA serious LAT relationship or a crazy machine? Metaphors in citizens’ perception of Belgian federalism
Perrez, Julien ULg; Reuchamps, Min

in Mots. Les Langages du Politique (in press)

This paper proposes a quantitative and qualitative corpus-based analysis of the use of metaphors in political discourse from the original perspective of citizen discourse. Our data were collected from ... [more ▼]

This paper proposes a quantitative and qualitative corpus-based analysis of the use of metaphors in political discourse from the original perspective of citizen discourse. Our data were collected from focus group discussions respectively held in the French-speaking and Dutch-speaking parts of Belgium, which tackled the citizens’ perceptions of Belgian federalism. Our findings suggest that citizens do produce metaphors when talking about complex political processes and that these metaphors reveal different political visions. This research also suggests differences in saliency of the source domains in terms of which citizens make sense of Belgian federalism. In this regard, the family domain, and more especially the metaphor BELGIAN FEDERALISM IS A LOVE RELATIONSHIP appears to function as an important conceptual reference point for the citizens’ understanding of the political relations in the Belgian context. [less ▲]

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See detailPeripheral blood stem cell graft compared to bone marrow after reduced intensity conditioning regimens for acute leukemia–A report from the ALWP of the EBMT
Savani, Bipin N.; Labopin, Myriam; Blaise, Didier et al

in Haematologica (in press)

Increasing numbers of patients are receiving reduced-intensity-conditioning regimen allogeneic hematopoietic stem-cell transplantation. We hypothesized that the use of bone-marrow graft might decrease the ... [more ▼]

Increasing numbers of patients are receiving reduced-intensity-conditioning regimen allogeneic hematopoietic stem-cell transplantation. We hypothesized that the use of bone-marrow graft might decrease the risk of graft-versus-host-disease compared to peripheral-blood after reduced-intensity-conditioning regimens without compromising graft-versus-leukemia effects. Patients who underwent reduced-intensity-conditioning regimen allogeneic hematopoietic stem-cell transplantation from 2000-2012 for acute leukemia and reported to the acute-leukemia-working-party of the EBMT were included in the study. Eight hundred thirty-seven patients receiving bone-marrow grafts were compared with 9011 peripheral-blood transplant recipients after reduced-intensity conditioning regimen. Median follow-up of surviving patients was 27 months. Cumulative incidence of engraftment (neutrophil≥0.5x109/L at day 60) was lower in bonemarrow recipients, 88 vs. 95% (p<0.0001). Grade II to IV acute graft-versus-hostdisease was lower in bone-marrow recipients, 19% vs. 24% for peripheral-blood (p=0.005). In multivariate analysis, after adjusting for differences between both groups, overall survival (HR 0.90; p=0.05) and leukemia-free-survival (HR 0.88; p=0.01) were higher in patients transplanted with peripheral-blood compared to bone-marrow grafts. Furthermore, peripheral-blood graft was also associated with decreased risk of relapse (HR 0.78; p=0.0001). Non-relapse-mortality was not significantly different between recipients of bone-marrow and peripheral-blood grafts, and chronic graft-versus-host-disease was significantly higher after peripheral blood grafts (HR 1.38; p<0.0001). Despite the limitation of a retrospective registry based study, we found that peripheral-blood grafts after reduced-intensity-conditioning regimens had better overall and leukemia-free survival than bone-marrow grafts. However, there is an increase in chronic graft-versus-host-disease after peripheral-blood grafts. Long-term follow-up is needed to clarify if chronic graft-versus-host-disease related deaths might increase the risk of late morbidity and mortality. [less ▲]

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See detailBiochemical characterization of the oil of durum wheat germ (Tunisian variety)
Kammoun, Maroua; Rassâa, Neila; Mejri-Gaïda, Myriam et al

in Journal of New Sciences (in press)

The wheat germ oil may constitute an alternative to the misuse of this cereal grain resource. The Tunisian exploitation is limited, at present, in the human and animal feed in the grain form, straw or ... [more ▼]

The wheat germ oil may constitute an alternative to the misuse of this cereal grain resource. The Tunisian exploitation is limited, at present, in the human and animal feed in the grain form, straw or some transformed products. For the purpose of characterization, the wheat germ oil has been extracted by Soxhlet apparatus from a Tunisian variety of durum wheat (Maali) based on the hexane as a solvent. An analysis by gas chromatography (GC) was then performed to identify and quantify the fatty acids of the oil. Then, the oil has submitted to a second chromatography analysis in liquid phase (HPLC) to quantify the tocopherols. The most important fatty acids constituting have been the two polyunsaturated acids linoleic acid C18:2 (OMEGA 6) and the gamma acid- linoleic C18:3 : 58.24 % and 4.19 % respectively; and the acid monounsaturated oleic acid C18:1 ( 24.49 %) but also some saturated acid: palmitic acid C16:0 with ( 19.50 % ), and the stearic acid C18:0 (1.29%). For this variety of Tunisian durum wheat, the wheat germ oil contains, in addition, 80.27 mg / 100g of α- tocopherols (vitamin E). The wheat germ oil extracted from the Tunisian variety 'Maali' has proved rich in vitamin E and omega-6 ; a better valorisation on the nutritional or pharmaceutical plan is to this title recommended. [less ▲]

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See detailMass-spectrometry-based method for screening of new peptide ligands for G-protein-coupled receptors
Cologna Takeno, Camila; Gilles, Nicolas; Echterbille, Julien ULg et al

in Analytical and Bioanalytical Chemistry (in press)

G-protein-coupled receptors (GPCRs) constitute the largest family of transmembrane proteins. Although implicated in almost all physiological processes in the human body, most of them remain unexploited ... [more ▼]

G-protein-coupled receptors (GPCRs) constitute the largest family of transmembrane proteins. Although implicated in almost all physiological processes in the human body, most of them remain unexploited, mostly because of the lack of specific ligands. The objective of this work is to develop a new mass-spectrometry-based technique capable of identifying new peptide ligands for GPCRs. The strategy is based on the incubation of cellular membranes overexpressing GPCRs with a mixture of peptides that contains potential ligands. Peptide ligands bind to the receptors, whereas other peptides remain in the binding buffer. Bound peptides are eluted from membranes and directly detected, identified, and characterized by MALDI TOF–TOF. The results reveal the efficacy of the procedure for selecting a specific ligand of GPCRs in both simple and complex mixtures of peptides. This new approach may offer direct purification, identification, and characterization of the new ligand in a single workflow. The proposed method is labeling-free and, unlike radio-binding and other techniques, it does not require a previously known labeled ligand of the studied GPCR. All these properties greatly reduce the experimental constraints. Moreover, because it is not based on the principle of a competitive specific binding, this technique constitutes a new tool to discover new ligands not only for known GPCRs, but also for orphan GPCRs [less ▲]

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See detailLoop
Levaux, Christophe ULg

in Rock Music Studies (in press)

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See detailPer una edizione integrale e analitica dell'incipit della Storia d'Italia di Francesco Guicciardini
Moreno, Paola ULg

in Laboratoire Italien : Politique et Société (in press)

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See detailRoot-emitted volatile organic compounds: can they mediate belowground plant-plant interactions?
Delory, Benjamin ULg; Delaplace, Pierre ULg; Fauconnier, Marie-Laure ULg et al

in Plant and Soil (in press)

Background Aboveground, plants release volatile organic compounds (VOCs) that act as chemical signals between neighbouring plants. It is now well documented that VOCs emitted by the roots in the plant ... [more ▼]

Background Aboveground, plants release volatile organic compounds (VOCs) that act as chemical signals between neighbouring plants. It is now well documented that VOCs emitted by the roots in the plant rhizosphere also play important ecological roles in the soil ecosystem, notably in plant defence because they are involved in interactions between plants, phytophagous pests and organisms of the third trophic level. The roles played by root-emitted VOCs in between- and within-plant signalling, however, are still poorly documented in the scientific literature. Scope Given that (1) plants release volatile cues mediating plant-plant interactions aboveground, (2) roots can detect the chemical signals originating from their neighbours, and (3) roots release VOCs involved in biotic interactions belowground, the aim of this paper is to discuss the roles of VOCs in between- and within-plant signalling belowground. We also highlight the technical challenges associated with the analysis of root-emitted VOCs and the design of experiments targeting volatile-mediated root-root interactions. Conclusions We conclude that root-root interactions mediated by volatile cues deserve more research attention and that both the analytical tools and methods developed to study the ecological roles played by VOCs in interplant signalling aboveground can be adapted to focus on the roles played by root-emitted VOCs in between- and within-plant signalling. [less ▲]

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See detailPerformance characteristics of the VIDAS 25-OH Vitamin D total assay - comparison with four immunoassays and two liquid chromatography-tandem mass spectrometry methods in a multicentric study
Moreau, E; Bächer, S; Mery, S et al

in Clinical Chemistry & Laboratory Medicine (in press)

Background: The study was conducted to evaluate the analytical and clinical performance of the VIDAS® 25-OH Vitamin D Total assay. The clinical performance of the assay was compared with four other ... [more ▼]

Background: The study was conducted to evaluate the analytical and clinical performance of the VIDAS® 25-OH Vitamin D Total assay. The clinical performance of the assay was compared with four other immunoassays against the results of two different liquid chromatography/ mass spectrometry methods (LC-MS/MS) standardized to NIST reference materials. Methods: VIDAS® 25-OH Vitamin D Total assay precision, linearity, detection limits and sample matrix comparison were assessed following CLSI guidelines. For method comparison, a total of 150 serum samples ranging from 7 to 92 ng/mL were analyzed by all the methods. Correlation was studied using Passing-Bablok regression and Bland- Altman analysis. The concordance correlation coefficient (CCC) was calculated to evaluate agreement between immunoassays and the reference LC-MS/MS method. In addition, samples containing endogenous 25(OH)D2 were used to assess each immunoassay’s ability to detect this analyte. Pregnancy and hemodialysis samples were used to the study the effect of vitamin D binding protein (DBP) concentration over VIDAS® assay performance. Results: The VIDAS® 25-OH Vitamin D Total assay showed excellent correlation to the LC-MS/MS results (y = 1.01x+0.22 ng/mL, r = 0.93), as obtained from two different sites and distinct LC-MS/MS methods. The limit of quantification was determined at 8.1 ng/mL. Cross-reactivity for 25(OH)D2 was over 80%. At concentrations of 10.5, 26 and 65.1 ng/mL, within-run CVs were 7.9%, 3.6% and 1.7%, while total CVs (between runs, calibrations, lots and instruments) were 16.0%, 4.5% and 2.8%. The VIDAS® performance was not influenced by altered DBP levels, though under-recovery of 25(OH)D as compared to LC-MS/ MS was observed for hemodialysis samples. Conclusions: The VIDAS® 25-OH Vitamin D Total assay is therefore considered suitable for assessment of vitamin D status in clinical routine. Keywords: assay performance; liquid chromatography/ [less ▲]

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See detailBreeding criteria and willingness-to-pay for improved Azawak zebu sires in Niger
Siddo, Seyni; Moula, Nassim ULg; Hamadou, Issa et al

in Archiv für Tierzucht = Archives Animal Breeding (in press)

In Niger, the growth in local demand for milk and meat makes it necessary to consider a genetic improvement of indigenous cattle. In Toukounous breeding station, the Azawak zebu has undergone over 50 ... [more ▼]

In Niger, the growth in local demand for milk and meat makes it necessary to consider a genetic improvement of indigenous cattle. In Toukounous breeding station, the Azawak zebu has undergone over 50 years of line breeding for milk and meat production traits. To understand the diffusion potential of improved Azawak sires in Niger, this study proposes to estimate the values that cattle keepers ascribe to different breeding criteria. In a first participatory stage, the breeding criteria used by cattle keepers were first listed and their relative importance was semi-quantified in three different production zones: agricultural, peri- urban and pastoral. The willingness-to-pay (WTP) for chosen breeding criteria have then been estimated through stated preference methods with 150 breeders. From participatory surveys, the most important attributes in sire choice were reproductive performance, feeding requirements, and docility. The criteria considered for conjoint analysis were feeding requirements, docility, meat or dairy type, reproductive performance, coat color, and tail length. The WTP was 149 € for low feed requirements, 139 € for docility, and 132 € for a long tail. The meat or dairy type of the sire showed a lesser importance in the decision-making. [less ▲]

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See detailThe scent of love: how important are semiochemicals in the sexual behavior of lady beetles?
Fassotte, Bérénice ULg; Francis, Frédéric ULg; Verheggen, François ULg

in Journal of Pest Science (in press)

Chemical signals are involved in the courtship behavior of many invertebrate and vertebrate species. Lady beetles are no exception to this rule; a significant number of published reports highlight the ... [more ▼]

Chemical signals are involved in the courtship behavior of many invertebrate and vertebrate species. Lady beetles are no exception to this rule; a significant number of published reports highlight the role of cuticular chemicals involved in the reproduction of lady beetles, including gender recognition. Recent data have also demonstrated the presence of a volatile female sex pheromone that facilitates male attraction in some species. Here, we present a synthetic overview of the current knowledge about the sexual behavior of lady beetles and associated chemicals for which the function and identification have been provided. Because lady beetles are often reared as biological control agents, the chemical cues involved in their sexual behavior could be used as components in integrated management approaches against soft-bodied hemipterans. In conclusion, this review provides new perspectives and potential developments for sustainable insect management mainly based on the semiochemicals involved in the sexual behavior of lady beetles. A better understanding of these chemical signals would help maximize their presence in areas where their predatory behavior is requested, as a result of the application of formulations inducing behavioral manipulation. [less ▲]

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See detailComment la participation à une recherche contribue au développement professionnel : le cas des exemples à l’Université
Fossion, Gilles ULg; Faulx, Daniel ULg

in Recherches Qualitatives (in press)

La recherche scientifique constitue un des piliers centraux de l’activité universitaire. Nous nous sommes donc questionnés sur les apprentissages générés par celle-ci. Après avoir brièvement décrit les ... [more ▼]

La recherche scientifique constitue un des piliers centraux de l’activité universitaire. Nous nous sommes donc questionnés sur les apprentissages générés par celle-ci. Après avoir brièvement décrit les objectifs et enjeux de cette communication, nous proposons une présentation des objectifs et de la méthodologie de la recherche que nous avons menée au sein des Facultés de Psychologie et des Sciences de l’Éducation de l’Université de Liège. Nous poursuivons, enfin, par la mise en évidence de ses principaux résultats. Ces résultats se situent sur deux niveaux. D’une part, nous présentons les résultats inhérents à la recherche - relative aux impacts générés par la mobilisation de l’exemple au sein du discours pédagogique - et qui contribue à l’enrichissement du champ scientifique abordé. D’autre part, nous abordons les résultats qui permettent la mise en évidence de l’aspect formatif que revêt la participation à une recherche scientifique pour les acteurs. [less ▲]

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See detailWeak magnetic field, solid-envelope rotation, and wave-induced N-enrichment in the SPB star zeta Cassiopeiae
Briquet, Maryline ULg; Neiner, C.; Petit, P. et al

in Astronomy and Astrophysics (in press)

Aims. The main-sequence B-type star zeta Cassiopeiae is known as a N-rich star with a magnetic field discovered with the Musicos spectropolarimeter. We model the magnetic field of the star by means of 82 ... [more ▼]

Aims. The main-sequence B-type star zeta Cassiopeiae is known as a N-rich star with a magnetic field discovered with the Musicos spectropolarimeter. We model the magnetic field of the star by means of 82 new spectropolarimetric observations of higher precision to investigate the field strength, topology, and effect. Methods. We gathered data with the Narval spectropolarimeter installed at Télescope Bernard Lyot (TBL; Pic du Midi, France) and applied the least-squares deconvolution technique to measure the circular polarisation of the light emitted from zeta Cas. We used a dipole oblique rotator model to determine the field configuration by fitting the longitudinal field measurements and by synthesizing the measured Stokes V profiles. We also made use of the Zeeman-Doppler imaging technique to map the stellar surface and to deduce the difference in rotation rate between the pole and equator. Results. zeta Cas exhibits a polar field strength B_pol of 100-150 G, which is the weakest polar field observed so far in a massive main-sequence star. Surface differential rotation is ruled out by our observations and the field of zeta Cas is strong enough to enforce rigid internal rotation in the radiative zone according to theory. Thus, the star rotates as a solid body in the envelope. Conclusions. We therefore exclude rotationally-induced mixing as the cause of the surface N-enrichment. We discuss that the transport of chemicals from the core to the surface by internal gravity waves is the most plausible explanation for the nitrogen overabundance at the surface of zeta Cas. [less ▲]

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See detailA new method to identify the endangered Pyrenean desman (Galemys pyrenaicus) and to study its diet, using next generation sequencing from faeces
Gillet, François ULg; Tiouchichine, Marie-Laure; Galan, Maxime et al

in Mammalian Biology (in press)

the Pyrenean Mountains and to the northern half of the Iberian Peninsula whose ecology and biology are still poorly known. The aim of this study was to identify Pyrenean desman faeces and to analyze its ... [more ▼]

the Pyrenean Mountains and to the northern half of the Iberian Peninsula whose ecology and biology are still poorly known. The aim of this study was to identify Pyrenean desman faeces and to analyze its diet from this material using next-generation sequencing methods. We amplified and sequenced a small DNA minibarcode (133 bp) of the COI gene in twenty-four putative faeces samples of Pyrenean desman and successfully identified the species in 16 samples. Other identified species were mammals, birds and amphibians, evidencing the potential application of our methods to a larger panel of taxa. In the Pyrenean desman faeces, we were able to identify nineteen prey species with a positive match (more than 98% of identity with a reference sequence) and eleven putative prey species with lower identity scores (90–96%). The nineteen species belonged to four orders and eleven families among which Trichoptera and Hydropsychidae were the most frequent, respectively. Future improvements could be obtained by extending the reference DNA sequence collection to reach precise identifications over the Desman’s range and by increasing the sampling to gain a better knowledge of the local diet of this endangered species. Such information is of great importance to propose the best management measures for its conservation. [less ▲]

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See detailForced Convective Drying of Wastewater Sludge with Presentation of Exergy Analysis of the Dryer
Bennamoun, Lyes; Fraikin, Laurent ULg; Li, Jie et al

in Chemical Engineering Communications (in press)

The main objective is studying the fundamental aspect, by the mean of the drying kinetics, the application of forced convective drying of wastewater sludge with determination of the optimum drying ... [more ▼]

The main objective is studying the fundamental aspect, by the mean of the drying kinetics, the application of forced convective drying of wastewater sludge with determination of the optimum drying conditions. The drying system is composed of two units; small samples of 2.5 g are dried in the first unit and bed of sludge weighting 250 g is dried the second unit. The experiments are performed under air temperatures varying between 80°C and 200°C. The range of the air velocity and its humidity is 1- 2 m/s and 0.005- 0.05 kgwater/kgdry air, respectively. The experiments are performed for two different sludges; activated sludge (AS) and thermalized and digested sludge (TDS). Usually, three main drying phases are observed during drying of bed of sludge. These phases are reduced to only two for small samples. Determination of the influent parameters shows that temperature of the drying air and sludge origin can profoundly influence the drying kinetic of the sludge. The exergy analysis of the two units of the drying system allows selecting 140 °C, 2 m/s, 0.05 kgwater/kgdry air as optimum drying condition with an exergy efficiency reaching 90\%. [less ▲]

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See detailDynamiques transactionnelles de reconnaissance et professionnalisation des stagiaires : perspectives pour la formation initiale
Dejean, Karine ULg

in Education et Formation (in press)

Cet article prend appui sur une recherche doctorale. A partir de l’analyse de récits d’expériences marquantes, à forte charge émotionnelle, rapportées par des enseignants débutants, des schémas ... [more ▼]

Cet article prend appui sur une recherche doctorale. A partir de l’analyse de récits d’expériences marquantes, à forte charge émotionnelle, rapportées par des enseignants débutants, des schémas d’intelligibilité de ces situations vécues ont été construits. Ceux-ci rendent compte des transformations identitaires et émotionnelles des enseignants débutants au travers des dynamiques transactionnelles de reconnaissance. Ces résultats ouvrent des perspectives pour la formation initiale des enseignants et l’accompagnement des enseignants débutants. Les schémas d’intelligibilité pourront être utilisés dans une démarche de réflexivité pour faciliter le décodage de situations professionnelles à forte charge émotionnelle vécues par l’enseignant et l’aider à donner sens à ses expériences [less ▲]

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See detailEmergent identity formation and the co-operative: Theory building in relation to alternative organizational forms
Nelson, Teresa; Nelson, Dylan; Huybrechts, Benjamin ULg et al

in Entrepreneurship and Regional Development (in press)

How are identities of alternative forms of organization constructed and how does this process differ relative to normative forms socially expected? In this research we consider identity formation in co ... [more ▼]

How are identities of alternative forms of organization constructed and how does this process differ relative to normative forms socially expected? In this research we consider identity formation in co-operatives, a population of organizations allied globally through values and practices such as democratic participation, voluntary and open membership, and limited return to capital investment. As an extension of current thinking on identity formation in entrepreneurship and organizational theory, we use co-operatives to explore social expectations and institutional arrangements around form at the societal, population, and organizational levels using a population ecology framework. We develop a research agenda based on propositions that address specific features of identity formation in less typical forms of organization, including tensions with normative business expectations, engagement with identity audiences, embeddedness in networks and alliances, structural factors influencing identity, and identity ambiguity. [less ▲]

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See detailThe impact of architectural representations on conveying design intent.
Cunin, Maxime; Yang, Maria C.; Elsen, Catherine ULg

in AI EDAM: Artificial Intelligence for Engineering Design Analysis and Manufacturing (in press)

Architects express themselves graphically in order to communicate ideas both to clients and to themselves. In practice, they rely on a variety of representations such as free-hand drawings, 3D computer ... [more ▼]

Architects express themselves graphically in order to communicate ideas both to clients and to themselves. In practice, they rely on a variety of representations such as free-hand drawings, 3D computer rendered images, and photomontages to convey their design intent. Research to date has demonstrated differences and commonalities in the ways in which expert designers and laymen perceive visual understanding. It is still unclear how architects themselves use different types of representations to express different intentions, and how accurately their expected audience perceives those intentions. The purpose of this research is to investigate how laymen interpret the initial design intent of an architect’s design, and what role different forms of representations play in this process of understanding a design. This paper describes a five-step process for developing a survey that was used to gather data from 686 laymen respondents. It was found that certain types of simpler representations presented in specific contexts are unexpectedly found to be a more efficient way to faithfully transmit an architectural intent. [less ▲]

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See detailGeographic range in liverworts: does sex really matter?
Laenen, B.; Machac, A.; Gradstein, S.R. et al

in Journal of Biogeography (in press)

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See detailThe Perceived Value of Passive Animal Health Surveillance: The Case of Highly Pathogenic Avian Influenza in Vietnam
Delabouglise, Alexis; Antoine-Moussiaux, Nicolas ULg; Phan, T.D et al

in Zoonoses and Public Health (in press)

Economic evaluations are critical for the assessment of the efficiency and sustain- ability of animal health surveillance systems and the improvement of their effi- ciency. Methods identifying and ... [more ▼]

Economic evaluations are critical for the assessment of the efficiency and sustain- ability of animal health surveillance systems and the improvement of their effi- ciency. Methods identifying and quantifying costs and benefits incurred by public and private actors of passive surveillance systems (i.e. actors of veterinary author- ities and private actors who may report clinical signs) are needed. This study pre- sents the evaluation of perceived costs and benefits of highly pathogenic avian influenza (HPAI) passive surveillance in Vietnam. Surveys based on participatory epidemiology methods were conducted in three provinces in Vietnam to collect data on costs and benefits resulting from the reporting of HPAI suspicions to vet- erinary authorities. A quantitative tool based on stated preference methods and participatory techniques was developed and applied to assess the non-monetary costs and benefits. The study showed that poultry farmers are facing several options regarding the management of HPAI suspicions, besides reporting the fol- lowing: treatment, sale or destruction of animals. The option of reporting was associated with uncertain outcome and transaction costs. Besides, actors antici- pated the release of health information to cause a drop of markets prices. This cost was relevant at all levels, including farmers, veterinary authorities and private actors of the upstream sector (feed, chicks and medicine supply). One benefit associated with passive surveillance was the intervention of public services to clean farms and the environment to limit the disease spread. Private actors of the poultry sector valued information on HPAI suspicions (perceived as a non-mon- etary benefit) which was mainly obtained from other private actors and media. [less ▲]

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See detailReview: Implementing biostimulants and biocontrol strategies in the agroecological management of cultivated ecosystems
Le Mire, Géraldine ULg; Nguyen, Minh ULg; Fassotte, Bérénice ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (in press)

This review describes the current methods for exploiting and applying plant growth-promoting rhizbacteria (PGPR), elicitors and semiochemical products in contemporary agricultural systems. The future of ... [more ▼]

This review describes the current methods for exploiting and applying plant growth-promoting rhizbacteria (PGPR), elicitors and semiochemical products in contemporary agricultural systems. The future of these biostimulant and biocontrol tools for the sustainable management of agricultural practices is also discussed. Special attention is given to the formulation of these products and the network of interactions taking place in cultivated ecosystems [less ▲]

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See detailState Created Barriers to Exit - The Example of the Acquisition of Alstom by General Electric
Petit, Nicolas ULg

in Competition Policy International (in press)

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See detailDPSC colonization of functionalized 3D textiles
Ortiz, Marine; Rosales-Ibáñez, R; Pozos-Guillén, A. et al

in Journal of Biomedical Materials Research, Part B : Applied Biomaterials (in press)

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See detailA Quantitative Doignon-Bell-Scarf theorem
Aliev, Iskander; Bassett, Robert; De Loera, Jesus et al

in Combinatorica (in press)

The famous Doignon-Bell-Scarf theorem is a Helly-type result about the existence of integer solutions to systems of linear inequalities. The purpose of this paper is to present the following quantitative ... [more ▼]

The famous Doignon-Bell-Scarf theorem is a Helly-type result about the existence of integer solutions to systems of linear inequalities. The purpose of this paper is to present the following quantitative generalization: Given an integer k, we prove that there exists a constant c(n,k), depending only on the dimension n and on the number k, such that if a bounded polyhedron {x in R^n : Ax <= b} contains exactly k integer points, then there exists a subset of the rows, of cardinality no more than c(n,k), defining a polyhedron that contains exactly the same k integer points. In this case c(n,0)=2^n as in the original case of Doignon-Bell-Scarf for infeasible systems of inequalities. We work on both upper and lower bounds for the constant c(n,k) and discuss some consequences, including a Clarkson-style algorithm to find the l-th best solution of an integer program with respect to the ordering induced by the objective function. [less ▲]

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See detailThe persea tree from Alexander to Late Antiquity: A contribution to the cultural and social history of Greco-Roman Egypt
Caneva, Stefano ULg

in Ancient Society (in press), 45

Although a great number of studies has already been devoted to the topic of sacred trees in Greco-Roman Egypt, this paper aims at offering a new contribution to this debate by shifting the focus of ... [more ▼]

Although a great number of studies has already been devoted to the topic of sacred trees in Greco-Roman Egypt, this paper aims at offering a new contribution to this debate by shifting the focus of research from the hitherto dominant interest in ancient and modern botanical classifications to the study of the socio-cultural contexts (and their diachronic changes) in which sacred trees were used in Hellenistic and Roman Egypt. The analysis focuses on the case study of the tree called περσ(ε)ία / persea in Greek and Latin sources. After drawing attention to the non-complete overlap between the denomination adopted by Greek and Latin authors for this Egyptian sacred plant and its “emic” Hieroglyphic / Demotic correspondents, ἰšd and šw3b, the focus will be on patterns of continuity, innovation and re-contextualization of Egyptian religious traditions in Ptolemaic and Roman Egypt and on the social actors and contexts that were involved in the use and protection of sacred plants. When approached from this perspective, the evidence on persea provides a fruitful dossier to investigate some aspects of the dialectic between continuity and transformation in cultural traditions, with particular regard to cases where traditions were adapted beyond cultural and ethnic limits. Moreover, the persea dossier enables us to discuss ancient contexts in which, for religious reasons, nature was seen as worth of being protected and preserved against the risk of extinction. This will allow us to raise some preliminary questions concerning the limits of applicability of modern environmental thinking to ancient cultures, in contexts in which the preservation of vegetal species was seen as an important value for the identity of a community, thus requiring individual and institutional commitment. [less ▲]

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See detailIs Darwin's 'Abominable Mystery' still a mystery today?
Cascales-Miñana, Borja ULg; Cleal, Chris J.; Gerrienne, Philippe ULg

in Cretaceous Research (in press)

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See detailQuadratization of symmetric pseudo-Boolean functions
Anthony, Martin; Boros, Endre; Crama, Yves ULg et al

in Discrete Applied Mathematics (in press)

A pseudo-Boolean function is a real-valued function $f(x)=f(x_1,x_2,\ldots,x_n)$ of $n$ binary variables; that is, a mapping from $\{0,1\}^n$ to ${\bbr}$. For a pseudo-Boolean function $f(x)$ on $\{0,1 ... [more ▼]

A pseudo-Boolean function is a real-valued function $f(x)=f(x_1,x_2,\ldots,x_n)$ of $n$ binary variables; that is, a mapping from $\{0,1\}^n$ to ${\bbr}$. For a pseudo-Boolean function $f(x)$ on $\{0,1\}^n$, we say that $g(x,y)$ is a quadratization of $f$ if $g(x,y)$ is a Quadratic polynomial depending on $x$ and on $m$ auxiliary binary variables $y_1,y_2,\ldots,y_m$ such that $f(x)= \min \{ g(x,y) : y \in \{0,1\}^m \} $ for all $x \in \{0,1\}^n$. By means of quadratizations, minimization of $f$ is reduced to minimization (over its extended set of variables) of the quadratic function $g(x,y)$. This is of some practical interest because minimization of quadratic functions has been thoroughly studied for the last few decades, and much progress has been made in solving such problems exactly or heuristically. A related paper initiated a systematic study of the minimum number of auxiliary $y$-variables required in a quadratization of an arbitrary function $f$ (a natural question, since the complexity of minimizing the quadratic function $g(x,y)$ depends, among other factors, on the number of binary variables). In this paper, we determine more precisely the number of auxiliary variables required by quadratizations of \emph{symmetric} pseudo-Boolean functions $f(x)$, those functions whose value depends only on the Hamming weight of the input $x$ (the number of variables equal to 1). [less ▲]

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See detailHistopathological effects of Aspergillus clavatus (Ascomycota: Trichocomaceae) on larvae of the southern house mosquito, Culex quinquefasciatus (Diptera: Culicidae)
Bawin, Thomas ULg; Seye, Fawrou; Boukraa, Slimane ULg et al

in Fungal Biology (in press)

Aspergillus clavatus (Ascomycota: Trichocomaceae) was previously found to be an opportunistic pathogen of mosquitoes (Diptera: Culicidae). In the present study, the mechanism leading to its insecticidal ... [more ▼]

Aspergillus clavatus (Ascomycota: Trichocomaceae) was previously found to be an opportunistic pathogen of mosquitoes (Diptera: Culicidae). In the present study, the mechanism leading to its insecticidal activity was investigated regarding histological damages on Culex quinquefasciatus larvae exposed to A. clavatus spores. Multiple concentration assays using spore suspensions (0.5 x 10^8 to 2.5 x 10^8 spores/ml) revealed 17.0% to 74.3% corrected mortalities after 48 h exposure. Heat-deactivated spores induced a lower mortality compared to non-heated spores suggesting that insecticidal effects are actively exerted. Spore-treated and untreated larvae were prepared for light microscopy as well as for scanning and transmission electron microscopy. Spores failed to adhere to the external body surface (except the mouth parts) of these aquatic immature stages but progressively filled the digestive tract where their metabolism seemed to activate. In parallel, the internal tissues of the larvae, i.e. the midgut wall, the skeletal muscles, and the cuticle-secreting epidermis, were progressively destroyed between 8 and 24 h of exposure. These observations suggest that toxins secreted by active germinating spores of A. clavatus in the digestive tract altered the larval tissues, leading to their necrosis and causing larval death. Fungal proliferation and sporulation then occurred during a saprophytic phase. A. clavatus enzymes or toxins responsible for these pathogenic effects need to be identified in further studies before any use of this fungus in mosquito control. [less ▲]

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See detailImaginer-lire le Capital
Pieron, Julien ULg

in Cahiers d'Etudes Germaniques (in press)

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See detailLe populisme aux Etats-Unis
Jamin, Jérôme ULg

in Revue de la Faculté de Droit de l'Université de Liège (in press)

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See detailDynamic Distribution and Interaction of the Arabidopsis SRSF1 Subfamily Splicing Factors
Stankovic, Nancy ULg; Schloesser, Marie ULg; Joris, Marine ULg et al

in Plant Physiology (in press)

Serine/Arginine-rich (SR) proteins are essential nucleus-localized splicing factors. Our prior studies showed that Arabidopsis RSZ22, a homolog of the human SRSF7 SR factor, exits the nucleus through two ... [more ▼]

Serine/Arginine-rich (SR) proteins are essential nucleus-localized splicing factors. Our prior studies showed that Arabidopsis RSZ22, a homolog of the human SRSF7 SR factor, exits the nucleus through two pathways, either dependent or independent on the XPO1 receptor. Here, we examined the expression profiles and shuttling dynamics of the Arabidopsis SRSF1 subfamily (SR30, SR34, SR34a and SR34b) under control of their endogenous promoter in Arabidopsis and in transient expression assay. Due to its rapid nucleocytoplasmic shuttling and high expression level in transient assay, we analysed the multiple determinants that regulate the localisation and shuttling dynamics of SR34. By site-directed mutagenesis of SR34 RNA-binding sequences and RS domain, we further show that functional RRM1 or RRM2 are dispensable for the exclusive protein nuclear localization and speckle-like distribution. However, mutations of both RRMs induced aggregation of the protein whereas mutation in the RS domain decreased the stability of the protein and suppressed its nuclear accumulation. Furthermore, the RNA-binding motif mutants are defective for their export through the XPO1 (CRM1/Exportin-1) receptor pathway, but retain nucleocytoplasmic mobility. We performed a yeast two hybrid screen with SR34 as bait and discovered SR45 as a new interactor. SR45 is an unusual SR splicing factor bearing two RS domains. These interactions were confirmed in planta by FLIM-FRET and BiFC and the roles of SR34 domains in protein-protein interactions were further studied. Altogether, our report extends our understanding of shuttling dynamics of Arabidopsis SR splicing factors [less ▲]

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See detailLe phénotype d’Akhenaton ; revue critique entre canons artistiques et expression pathologique.
JEDIDI, Zayd ULg; JEDIDI, Haroun ULg; LAVEAUX, Elisabeth et al

in Revue Médicale de Liège (in press)

Of all the royal families of ancient or modern fame, few are as iconic as the eighteenth dynasty of pharaohs of the New Kingdom of Egypt, whose opulence and deeds we are still familiar to nearly 3,500 ... [more ▼]

Of all the royal families of ancient or modern fame, few are as iconic as the eighteenth dynasty of pharaohs of the New Kingdom of Egypt, whose opulence and deeds we are still familiar to nearly 3,500 years after their time. Tenth pharaoh of this dynasty and father of Tutankhamun, Akhenaten (Amenhotep/Amenhotep IV) still fascinates Egyptologists and history lovers through the many questions surrounding his atypical rule. One of the most striking aspects of the so-called Amarna period concerns the representations of the pharaoh himself, very confusing compared to the traditional iconography of the New Kingdom. These intriguing portraits of Pharaoh raised a whole lot of medical assumptions, more or less substantiated. We review here the main theories developed throughout history. [less ▲]

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See detailInvectif et logique conflictuelle dans le champ du rap français
Saint-Amand, Denis ULg

in Etudes de Lettres (in press)

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See detailOption Replication and the Performance of a Market Timer
Hübner, Georges ULg

in Studies in Economics & Finance (in press)

The Treynor and Mazuy framework is a widely used return-based model of market timing. However, existing corrections to the regression intercept can be manipulated through derivatives trading. We propose ... [more ▼]

The Treynor and Mazuy framework is a widely used return-based model of market timing. However, existing corrections to the regression intercept can be manipulated through derivatives trading. We propose an adjustment based on Merton's option replication approach. The linear and quadratic coefficients of the regression are exploited to assess the cost of the replicating option that yields similar convexity for a passive portfolio. A similar reasoning applies for various timing patterns and in multi-factor models. The proposed framework induces a potential rebalancing risk and involves the delicate issue of choosing the cheapest option. We show that these issues can be overcome for reasonable tolerance levels. [less ▲]

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See detailAnalgesic Efficacy and Safety of Curcuminoids in Clinical Practice: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Sahebkar, A; Henrotin, Yves ULg

in Pain Medicine : The Official Journal of the American Academy of Pain Medicine (in press)

Background. Curcuminoids are natural products with potent anti-inflammatory and antioxidant properties. There have been a number of reports on the analgesic effects of curcuminoids in clinical trials, yet ... [more ▼]

Background. Curcuminoids are natural products with potent anti-inflammatory and antioxidant properties. There have been a number of reports on the analgesic effects of curcuminoids in clinical trials, yet data have not been fully conclusive. Objectives. To provide the highest level of evidence on the efficacy of curcuminoids in patients with painful conditions through meta-analysis of data from randomized controlled trials (RCTs). Methods. A systematic review and meta-analysis was conducted using data reported by RCTs. The primary efficacy measure was pain intensity or algofunctional status. Treatment effect was summarized with standardized mean difference (SMD) calculated from differences in means of pain measures between treatment and control groups using a random-effects model. Results. A total of eight RCTs met our inclusion criteria that included 606 randomized patients. Curcuminoids were found to significantly reduce pain (SMD: −0.57, 95% CI: −1.11 to −0.03, P = 0.04). This pain-relieving effect was found to be independent of administered dose and duration of treatment with curcuminoids, and was free from publication bias. Curcuminoids were safe and well tolerated in all evaluated RCTs. Conclusion. Curcuminoids supplements may be a safe and effective strategy to improve pain severity, by warranting further rigorously conducted studies to define the long-term efficacy and safety. [less ▲]

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See detailP.Bour. 1 (P.Sorb. inv. 826 = MP³ 2643) : reconstruction codicologique
Carlig, Nathan ULg

in Zeitschrift für Papyrologie und Epigraphik (in press)

Based on the autopsy of the 11 folios of P.Bour. 1, the article identifies the original form of this school book, that is a series of 4 biniones, of which only the 1st and the 3rd are entirely kept. The ... [more ▼]

Based on the autopsy of the 11 folios of P.Bour. 1, the article identifies the original form of this school book, that is a series of 4 biniones, of which only the 1st and the 3rd are entirely kept. The survey was pursued with the study of rests of binding and of the state os preservation of each folio. [less ▲]

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See detailIgnorance et maîtrise de la bête. Lefort critique de l'éducation "humaniste".
Mancuso, Eva ULg

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

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See detailCutaneous involvement in multiple myeloma: a multi-institutional retrospective study of 53 patients
Jurczyszyn, .; Olszewska-Szopa, M.; Hungria, V. et al

in Leukemia & Lymphoma (in press)

Skin infiltration in multiple myeloma (skin MM) is a rare clinical problem. Only a few cases of skin involvement have been reported, primarily in single case reports. We analyzed and present the clinical ... [more ▼]

Skin infiltration in multiple myeloma (skin MM) is a rare clinical problem. Only a few cases of skin involvement have been reported, primarily in single case reports. We analyzed and present the clinical outcomes, immunohistochemistry and cytogenetic features, and relevant laboratory data on 53 biopsy-proven skin MM cases. The median time from MM diagnosis to skin involvement was 2 years. There appears to be an overrepresentation of immunoglobulin class A (IgA) and light chain disease in skin MM. We found no correlation between CD56 negative MM and skin infiltration. We found that skin MM patients presented in all MM stages (i.e. ISS stages I to III), and there was no preferential cytogenetic abnormality. Patients with skin MM carry a very poor prognosis with a median overall survival (OS) of 8.5 months as time from skin involvement. Moreover, patients with IgA disease and plasmablastic morphology appear to have a worse OS. [less ▲]

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See detailEtude de la séquence stratigraphique des loess de la carrière de Romont (Eben-Emael, Belgique) par une campagne géotechnique
Delvoie, Simon ULg; Pirson, Stéphane ULg; Charlier, Robert ULg et al

in Notae Praehistoricae (in press), 36

The Romont quarry is recently considered as a new type section for the Middle Belgium loess deposits. The site displays a nearly 10 m thick loess sequence mainly dating from the Upper Pleistocene. The ... [more ▼]

The Romont quarry is recently considered as a new type section for the Middle Belgium loess deposits. The site displays a nearly 10 m thick loess sequence mainly dating from the Upper Pleistocene. The Rocourt Pedocomplex, the Humiferous Complex of Remicourt, the Malplaquet Soil and the Nagelbeek Tongued Horizon are especially well developed. Classical approaches to study the loess sequence need observable sections. Unfortunately these sections are rare in Middle Belgium, often temporary and not deep enough. To identify reference horizons, archaeologists and geologists use to resort to hand auger sampling techniques. Investigation of loess by cone penetration tests could offer an alternative to the lack of outcrops and could be used complementary to hand drilling techniques. This study focuses on a methodology to approach as a first step the loess sequence to identify the presence or not of some layers and their extension. The investigation campaign performed on the site of Romont aims to define reference horizons based on mechanical properties by comparison with an observable outcrop. Then 16 cone penetration tests have been realized behind the working face. The campaign results reveal the existence of some horizons into the loess sequence. The transition between the Humiferous Complex of Remicourt and the Rocourt Pedocomplex is the most noticeable horizon. These two pedostratigraphic units are important due to the presence of archaeological materials in Middle Belgium and borderlands. Closer to the surface the Nagelbeek Tongued Horizon and the decarbonation limit are also highlighted from results of the geotechnical campaign. [less ▲]

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See detailIs the sword moss (Bryoxiphium) a preglacial Tertiary relict?
Patino, J.; Goffinet, B.; Sim-Sim, M.A. et al

in Molecular Phylogenetics & Evolution (in press)

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See detailLa flexicurité revisitée : analyse qualitative interdisciplinaire du discours de travailleurs à l'aide d'un logiciel collaboratif »
Beuker, Laura ULg; DE CIA, Julie ULg; Dervaux, Amélie ULg et al

in Recherches Qualitatives (in press)

L’ambition de cet article est double : explorer les vertus de l’utilisation d’un logiciel d’analyse qualitative dans le cadre d’un travail interdisciplinaire sur la flexicurité, et réaliser une revue de ... [more ▼]

L’ambition de cet article est double : explorer les vertus de l’utilisation d’un logiciel d’analyse qualitative dans le cadre d’un travail interdisciplinaire sur la flexicurité, et réaliser une revue de littérature transversale à partir des problématiques concrètes que ce concept cristallise dans le vécu des travailleurs. La flexicurité constitue un oxymore qui prône la recherche d’un équilibre entre besoins de flexibilité et de sécurité sur le marché du travail. Cet équilibre est avant tout un objectif politique, mais il reste fragile aux yeux des acteurs concernés. En cherchant à croiser le regard analytique de trois disciplines – psychologie, gestion et sociologie –, nous avons recouru au logiciel Cassandre (Lejeune, 2008) pour dégager des tensions discursives autour des notions de flexibilité et de sécurité dans un corpus de vingt entretiens qualitatifs. L’article permet ainsi de concrétiser l’intérêt et les limites de l’utilisation d’un logiciel d’analyse qualitative dans le cadre d’un travail interdisciplinaire. [less ▲]

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See detailTransient performance evaluation of waste heat recovery Rankine cycle based system for heavy duty trucks
Grelet, Vincent; Reiche, Thomas; Lemort, Vincent ULg et al

in Applied Energy (in press)

The study presented in this paper aims to evaluate the transient performance of a waste heat recovery Rankine cycle based system for a heavy duty truck and compare it to steady state evaluation. Assuming ... [more ▼]

The study presented in this paper aims to evaluate the transient performance of a waste heat recovery Rankine cycle based system for a heavy duty truck and compare it to steady state evaluation. Assuming some conditions to hold, simple thermodynamic simulations are carried out for the comparison of several fluids. Then a detailed rst principle based model is also presented. Last part is focused on the Rankine cycle arrangement choice by means of model based evaluation of fuel economy for each concept where the fuels savings are computed using two methodologies. Fluid choice and concept optimization are conducted taking into account integration constraints (heat rejection, packaging . . . ). This paper shows the importance of the modeling phase when designing WHRS and yields a better understanding when it comes to a vehicle integration of a Rankine cycle in a truck. [less ▲]

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See detailComputerized adaptive testing with R: Recent updates of the package catR
Magis, David ULg; Barrada, Juan Ramon

in Journal of Statistical Software (in press)

The purpose of this paper is to list the recent updates of the R package catR. This package allows for generating response patterns under a computerized adaptive testing (CAT) framework with underlying ... [more ▼]

The purpose of this paper is to list the recent updates of the R package catR. This package allows for generating response patterns under a computerized adaptive testing (CAT) framework with underlying item response theory (IRT) models. Among the most important updates, well-known polytomous IRT models are now supported by catR; several item selection rules have been added; and it is now possible to perform post-hoc simulations. Some functions were also rewritten or withdrawn to improve the usefulness and performances of the package. [less ▲]

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See detailBott type periodicity for the higher octonions
Kreusch, Marie ULg

in Journal of Noncommutative Geometry (in press)

We study the series of complex nonassociative algebras $\bbO_n$ and real nonassociative algebras $\bbO_{p,q}$ introduced in~\cite{MGO2011}. These algebras generalize the classical algebras of octonions ... [more ▼]

We study the series of complex nonassociative algebras $\bbO_n$ and real nonassociative algebras $\bbO_{p,q}$ introduced in~\cite{MGO2011}. These algebras generalize the classical algebras of octonions and Clifford algebras. The algebras $\bbO_{n}$ and $\bbO_{p,q}$ with $p+q=n$ have a natural $\Z_2^n$-grading, and they are characterized by cubic forms over the field $\Z_2$. We establish a periodicity for the algebras~$\bbO_{n}$ and $\bbO_{p,q}$ similar to that of the Clifford algebras $\mathrm{Cl}_{n}$ and~$\mathrm{Cl}_{p,q}$. [less ▲]

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See detailInfluence of the secondary endosymbiont Serratia Symbiotica on the resistance to the parasitism in the aphid Acyrthosiphon pisum
Attia, Sabrine; Foray, Vincent; Louâpre, Philippe et al

in Journal of Entomology and Zoology Studies (in press)

Aphids have an obligate association with the primary symbiont Buchnera aphidicola and is known to affect aphid fitness. Aphids commonly harbour other facultative bacterial endosymbionts and may benefit ... [more ▼]

Aphids have an obligate association with the primary symbiont Buchnera aphidicola and is known to affect aphid fitness. Aphids commonly harbour other facultative bacterial endosymbionts and may benefit from their presence through increased resistance to parasitoids [1]. Present results suggest that the ability of hosts to defend against natural enemies depend not only on the presence of symbionts but also on the host genotype. Aphids represent a complex micro-environment for the parasitoid larvae and both the aphid physiology and endosymbiont influence their survival until mummification. [less ▲]

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See detailOutplacement adequacy and benefits: The mediating role of overall justice.
Marzucco, Laurence ULg; Hansez, Isabelle ULg

in Journal of Employment Counseling (in press)

Despite a rapid growth and an ongoing need for outplacement services, little is yet known about the perceived adequacy and benefits of these services for redundant employees using them. We surveyed 360 ... [more ▼]

Despite a rapid growth and an ongoing need for outplacement services, little is yet known about the perceived adequacy and benefits of these services for redundant employees using them. We surveyed 360 Belgian redundant employees (i.e., clients) using outplacement services provided by a public employment agency. The results indicate that an outplacement experience perceived as adequate for clients fosters their overall impressions of justice towards the dismissing organization; this leads in turn to benefits for them: reduction of negative emotions, enhancement of their perceived well-being, future perspectives, and job-seeking activities - confirming the mediating role of overall justice. [less ▲]

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See detailSteel hollow columns with an internal profile filled with self-compacting concrete under fire conditions
Chu, Thi Binh; Gernay, Thomas ULg; Dotreppe, Jean-Claude ULg et al

in Proceeding of the Romanian Academy. Series A, Mathematics, Physics, Technical Sciences, Information Science (in press)

A detailed experimental and numerical investigation has been performed on the behavior under fire conditions of concrete filled steel hollow section (CFSHS) columns. In this study the internal ... [more ▼]

A detailed experimental and numerical investigation has been performed on the behavior under fire conditions of concrete filled steel hollow section (CFSHS) columns. In this study the internal reinforcement consists of another profile (tube or H section) being embedded with the concrete, and filling is realized by self-compacting concrete (SCC). Ten columns filled with self-compacting concrete embedding another steel profile have been tested in the Fire Testing Laboratory of the University of Liege, Belgium. Numerical simulations on the thermal and structural behavior of these elements have been made using the non linear finite element software SAFIR developed at the University of Liege. There is a rather good agreement between numerical and experimental results, which can be slightly improved by using the ETC (Explicit Transient Creep) model incorporated in SAFIR. This shows that numerical analyses can predict well the behavior of CFSHS columns under fire conditions. The properties at high temperatures of self-compacting concrete are considered the same as those of ordinary concrete. [less ▲]

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See detailAn Economic Appraisal of MOOC Platforms: Business Models and Impacts on Higher Education
Jacqmin, Julien ULg; belleflamme, paul

in CESifo Economic Studies (in press)

We use various economic and pedagogical concepts to understand the specificities of MOOC (Massive Online Open Courses) platforms. We discuss how the private provision of MOOCs can be sustained. Using the ... [more ▼]

We use various economic and pedagogical concepts to understand the specificities of MOOC (Massive Online Open Courses) platforms. We discuss how the private provision of MOOCs can be sustained. Using the theory of multisided platforms, we analyze five ways to monetize the MOOC business. We then claim that MOOC platforms can play a key transformative role in the higher education sector by making teaching practices evolve, rather than by replacing incumbent institutions. Finally, we derive a number of directions for public policy [less ▲]

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See detailMinor compounds and oxidative stability of mono-varietal virgin olive oils produced in eastern of Morocco
Mansouri, Farid; Benmoumen, Abdessamad; Richard, Gaetan ULg et al

in Food Chemistry (in press)

The aim of this study is to characterize monovarietal virgin olive oils (VOOs) of new high-density plantings system of three cultivars (Arbequina, Arbosana and Koroneiki) which have been recently ... [more ▼]

The aim of this study is to characterize monovarietal virgin olive oils (VOOs) of new high-density plantings system of three cultivars (Arbequina, Arbosana and Koroneiki) which have been recently introduced in the eastern mediterranean region of Morocco. In this study, we have also conducted comparison between those monovarietal VOOs and olive oil of the local olive cultivar Picholine marocaine. Monovarietal VOOs characterization has been carried out by analysing several parameters, including quality index and olive oil stability to oxidation. Significant differences between the analysed olive oils were highlighted. They depend on cultivars and technological conditions of processing. We have noticed that Koroneiki olive oil have higher content of phenols (459.48 mg kg-1) and have the best value of oxidative stability (93.16 h). On the other hand Arbrosana’s VOO has low content of total phenols (260.85 mg kg-1) but it was distinguished by its higher content of alpha-tocopherol (460.07 mg kg-1). In addition, ten phenolic compounds present in virgin olive oils, were identified and quantitatively assessed by HPLC. Hydroxytyrosol, tyrosol, luteoline, pinoresinol and apigenin were the main phenolic compounds in those analyzed monovarietal VOOS. [less ▲]

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See detailAutomatic learning of fine operating rules for online power system security control
Sun, Hongbin; Zhao, Feng; Wang, Huifang et al

in IEEE Transactions on Neural networks and learning systems (in press)

Fine operating rules for security control and an automatic system for their online discovery were developed to adapt to the development of smart grids. The automatic system uses the real-time system state ... [more ▼]

Fine operating rules for security control and an automatic system for their online discovery were developed to adapt to the development of smart grids. The automatic system uses the real-time system state to determine critical flowgates, and then a continuation power flow-based security analysis is used to compute the initial transfer capability of critical flowgates. Next, the system applies the Monte Carlo simulations to expected short-term operating condition changes, feature selection, and a linear least squares fitting of the fine operating rules. The proposed system was validated both on an academic test system and on a provincial power system in China. The results indicated that the derived rules provide accuracy and good interpretability and are suitable for real-time power system security control. The use of high-performance computing systems enables these fine operating rules to be refreshed online every 15 min. [less ▲]

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See detailReforming the Postal Universal Service
Gautier, Axel ULg; Poudou, Jean-Christophe

in Review of Network Economics (in press)

The postal sector has undergone dramatic changes over the recent years under the double effect of ongoing liberalization and increased competition with alternative communication channels (e-substitution ... [more ▼]

The postal sector has undergone dramatic changes over the recent years under the double effect of ongoing liberalization and increased competition with alternative communication channels (e-substitution). As a result, the mail volume handled by the historical operator has declined sharply while the latter's ability to match the same standard of universal service may be under threat. Thus, a reform of the postal universal service is on the agenda. This paper examines possible reforming options ranging from keeping universal service within the postal sector to redefining universal service as spanning postal and electronic technologies. [less ▲]

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See detailSiting Controversies Analysis: Framework and Method for Questioning the Procedure
Rossignol, Nicolas ULg; Parotte, Céline ULg; Joris, Geoffrey ULg et al

in Journal of Risk Research (in press)

Siting controversies are commonplace, as well against the construction of roads, railways, nuclear waste disposals, as against windfarms. Local citizens resist against siting decisions taken by the ... [more ▼]

Siting controversies are commonplace, as well against the construction of roads, railways, nuclear waste disposals, as against windfarms. Local citizens resist against siting decisions taken by the authorities, following a dynamics often quoted as ‘Not In My Back Yard’. Yet contested for its lack of analytical value, NIMBY is still used strategically by actors to qualify citizens as irrational and egoistic. Beyond this labelling, many factors are investigated to understand the dynamics behind siting controversies. In this paper, we focus on the impact of the legal procedure structuring the implantation of windfarms in the Walloon Region (Belgium), and its translations within different decision making processes in specific case studies. To that regard, we consider the legal procedure as a ‘public policy instrument’. It is neither neutral nor natural, and carry values and interests. It organizes inter-personal relations between actors, and is potentially catalyzer of frustrations. In addition, this legal procedure is the object of translations within different contexts, including different actors participating to specific decision making processes. The empirical approach of this paper is based on case studies data and on the use of an innovative methodology called ‘Open Process Workshop’. This methodology consists in a structured workshop with key stakeholders, during which the legal procedure is questioned. Overall, we demonstrate that the focus on the legal procedure - and its translations within different decision making processes - allows systemic analysis providing deep understandings of controversies and reaffirming the interlinks between ‘the social’ and ‘the technical’ in such controversies. In addition, we argue that the methodology used fosters the production of innovative knowledge, mutual understanding and collective learning between the participants. [less ▲]

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See detailMicrobiological zoonotic emerging risks, transmitted between livestock animals and humans (2007-2015)
Filippitzi, ME; Goumperis, T; Robinson, T et al

in Transboundary and emerging diseases (in press)

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See detailEmerging ecosystem services governance issues in the Belgium ecosystem services community of practice
Keune, Hans; Dendoncker, Nicolas; Popa, Florin et al

in Ecosystem Services (in press)

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See detailMetal binding to the N-terminal cytoplasmic domain of the PIB ATPase HMA4 is required for metal transport in Arabidopsis.
Laurent, Clémentine ULg; Lekeux, Gilles ULg; Ukuwela, Ashwinie A et al

in Plant Molecular Biology (in press)

PIB ATPases are metal cation pumps that transport metals across membranes. These proteins possess N- and C-terminal cytoplasmic extensions that contain Cys- and His-rich high affinity metal binding ... [more ▼]

PIB ATPases are metal cation pumps that transport metals across membranes. These proteins possess N- and C-terminal cytoplasmic extensions that contain Cys- and His-rich high affinity metal binding domains, which may be involved in metal sensing, metal ion selectivity and/or in regulation of the pump activity. The PIB ATPase HMA4 (Heavy Metal ATPase 4) plays a central role in metal homeostasis in Arabidopsis thaliana and has a key function in zinc and cadmium hypertolerance and hyperaccumulation in the extremophile plant species Arabidopsis halleri. Here, we examined the function and structure of the N-terminal cytoplasmic metal-binding domain of HMA4. We mutagenized a conserved CCTSE metal-binding motif in the domain and assessed the impact of the mutations on protein function and localization in planta, on metal-binding properties in vitro and on protein structure by Nuclear Magnetic Resonance spectroscopy. The two Cys residues of the motif are essential for the function, but not for localization, of HMA4 in planta, whereas the Glu residue is important but not essential. These residues also determine zinc coordination and affinity. Zinc binding to the N-terminal domain is thus crucial for HMA4 protein function, whereas it is not required to maintain the protein structure. Altogether, combining in vivo and in vitro approaches in our study provides insights towards the molecular understanding of metal transport and specificity of metal P-type ATPases. [less ▲]

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See detailExperimental Tests and Numerical Modelling on Slender Steel Columns at High Temperatures
Franssen, Jean-Marc ULg; Zhao, Bin; Gernay, Thomas ULg

in Journal of Structural Fire Engineering (in press)

This paper is about a series of experimental fire tests on eight full scale steel columns made of slender I shaped class 4 sections. Six columns were made of welded sections (some prismatic and some ... [more ▼]

This paper is about a series of experimental fire tests on eight full scale steel columns made of slender I shaped class 4 sections. Six columns were made of welded sections (some prismatic and some tapered members) and two columns were made of hot rolled sections. The nominal length of the columns was 2.7 meters with the whole length being heated. The load was applied at ambient temperature after which the temperature was increased under constant load. The load was applied concentrically on some tests and with an eccentricity in other tests. Heating was applied by electrical resistances enclosed in ceramic pads. Numerical simulations were performed with the software SAFIR® using shell elements. The paper presents the results obtained in terms of failure mode and ultimate temperature, in the experimental tests and in the numerical simulations. [less ▲]

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See detailIncreased diversification rates correlate with bisexuality in liverworts
Laenen, B.; Machac, A.; Gradstein, S.R. et al

in New Phytologist (in press)

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See detailMonitoring the laccase reaction of vanillin and poplar hydrolysate
Sòti, Valentin; Jacquet, Nicolas ULg; Apers, Sandra et al

in Journal of Chemical Technology & Biotechnology (in press)

BACKGROUND: Laccase is an intensively researched enzyme for industrial use. Except for decolorisation measurements, HPLC analysis is the conventional method for monitoring the phenolic removal during ... [more ▼]

BACKGROUND: Laccase is an intensively researched enzyme for industrial use. Except for decolorisation measurements, HPLC analysis is the conventional method for monitoring the phenolic removal during laccase enzyme reaction. This paper reports an investigation of the continuous UV absorbance follow-up of the laccase reaction with steam pretreated poplar hydrolysate. RESULTS: Vanillin was used as a model substrate and lignocellulose xylose rich fraction (XRF) as a biologically complex substrate for laccase detoxification. The reaction was followed by HPLC-UV as well as by UV spectrometric measurements. Results suggest that the reaction can be successfully monitored by measuring the change of UV absorbance at 280 nm, without previous compound separation. In case of XRF experiments the spectrophotometric follow-up is especially useful, as HPLC analysis takes a long time and provides less information than in case of single substrates. The method seems to be suitable for optimization and process control. CONCLUSION: The obtained results can help to construct a fast, easy and straightforward monitoring system for laccase-phenolic substrate reactions. [less ▲]

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See detailLa collaboration entre architectes et plasticiens à Liège dans les années 1930.
Charlier, Sébastien ULg

in In Situ, revue des patrimoines (in press), 26

En 1928, des étudiants de l’Académie des Beaux-Arts de Liège fondent la revue d’architecture et d’urbanisme L’Équerre. S’inscrivant bien que tardivement dans la continuité des avant-gardes internationales ... [more ▼]

En 1928, des étudiants de l’Académie des Beaux-Arts de Liège fondent la revue d’architecture et d’urbanisme L’Équerre. S’inscrivant bien que tardivement dans la continuité des avant-gardes internationales, le mensuel revendique une vision transversale de l’architecture où la réflexion plastique occupe une place centrale. Dès le départ, elle s’associe à Anthologie, revue imprégnée des théories futuristes et qui diffuse les artistes de l’avant-garde locale. D’abord par le biais de l’édition et des expositions, plasticiens et architectes travaillent ensuite ensemble dans le cadre de projets ambitieux financés par les pouvoirs publics. Cette contribution revient aux racines de cette collaboration en définissant les liens théoriques ou personnels unissant les deux revues. En se concentrant sur les infrastructures publiques, elle comment les artistes et les architectes ont répondu ensemble aux exigences concrètes de la commande en les replaçant dans le contexte social, politique et économique d’une ville belge de seconde importance à la veille de la Seconde Guerre mondiale. [less ▲]

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See detailAre neural crest stem cells the missing link between hematopoietic and neurogenic niches?
Coste, Cécile ULg; Neirinckx, Virginie ULg; Gothot, André ULg et al

in Frontiers in Cellular Neuroscience (in press)

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See detailThe new Belgian Senate. A (dis)continued evolution of federalism in Belgium?
Dandoy, Régis; Dodeigne, Jérémy ULg; Vandeleene, Audrey et al

in Representation (in press)

The 2012–14 reform of the Belgian state has deeeply transformed its Senate. Not only does the reform reduce the legislative powers of the Belgian upper chamber, but it also alters its composition. The ... [more ▼]

The 2012–14 reform of the Belgian state has deeeply transformed its Senate. Not only does the reform reduce the legislative powers of the Belgian upper chamber, but it also alters its composition. The former appointment of Senators based on a system of direct and community-based election is replaced by a system of indirect and mixed regional and community-based designation. This article presents this important reform. On the basis of a comprehensive dataset of federal and regional political careers, it also comparatively analyses the profile of the Senators, before and after the reform. Overall, although rules regarding seats allocation have been thoroughly remodelled, we conclude that the reform had neither dramatically affected the subtle balances upon which the Belgian federal state relies nor altered the patterns of Senators’ profiles. [less ▲]

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See detailThe terrestrialization process: A palaeobotanical and palynological perspective.
Meyer-Berthaud, Brigitte; Servais, Thomas; Vecoli, Marco et al

in Review of Palaeobotany and Palynology (in press)

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See detailCultural Marxism : A Survey
Jamin, Jérôme ULg

in Religion Compass (in press)

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See detailTraumatologie du rugby à 7
KAUX, Jean-François ULg; Julia, Marc; Delvaux, François ULg et al

in Science & Sports (in press)

Aims. — To estimate the risk of injury in rugby sevens.News. — The rugby sevens is an increasingly popular sport since the creation of the IRB SevensWorld Series in 2000 and its introduction as an Olympic ... [more ▼]

Aims. — To estimate the risk of injury in rugby sevens.News. — The rugby sevens is an increasingly popular sport since the creation of the IRB SevensWorld Series in 2000 and its introduction as an Olympic sport in 2016. Despite its strong simi-larities to rugby union, it remains a different sport with higher game intensity, causing a moresignificant number of injuries. The average incidence of injury in rugby sevens is 249.27 for1000 hours of play against 102.25 for 1000 hours of rugby union matches.Conclusion. — This epidemiological review of injuries among the rugby sevens refers to theirlocation and their nature, the causes, the position of players, the type of field, as well as thedowntime of practice following trauma. [less ▲]

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See detailPrediction of the post-dilution hematocrit during cardiopulmonary bypass. Are new formulas needed?
ERPICUM, Marie ULg; Dardenne, Nadia ULg; HANS, Grégory ULg et al

in Perfusion (in press)

Objectives: Predicting the post-dilution hematocrit is an important tool to avoid preventable anemia or unnecessary transfusion. Simplified empirical formulas currently used for such a prediction may lead ... [more ▼]

Objectives: Predicting the post-dilution hematocrit is an important tool to avoid preventable anemia or unnecessary transfusion. Simplified empirical formulas currently used for such a prediction may lead to large errors. We aimed to improve the accuracy of these formulas by a better estimation of the dilution volume and the patient circulatory blood volume. Methods: We compared the estimation accuracy of two formulas, using fixed (formula A) versus estimated (formula D) dilution volume and patient circulatory blood volume for 100 cardiac interventions. The difference between predicted and measured HctT1 was considered as “good” if less than 0.5%, “moderate” between 0.5 and 2% and “poor” if higher than 2%. The influence of the body mass index (BMI) on patient blood volume estimation was explored by categorized groups’ comparison. Results: The mean difference between predicted and measured HctT1 differed significantly between formulas A and D. Formula A didn’t differ from HctT1 (p=0.19, IC95% [-0.89-0.18]), but a significant and higher underestimation was observed in the BMI⩽25 group compared to the other BMI groups (p<0.001). Formula D overestimated HctT1 (p<0.001, IC95% [1.01-1.93]) without a difference between the BMI groups. No difference was observed in their overall proportions of good (11 vs 10%), moderate (44 vs 46%) and poor predictions (47 vs 44%) (p=0.117). Conclusions: Formulas used for post-dilution hematocrit prediction lead to major estimation errors and a risk of inadequate transfusion practices. Estimations performed by experienced clinicians could not minimize these biases in all clinical cases as significant errors remain, with potential clinical impact. No estimation formula should be used as a hard tool for transfusing patients, but rather as a guide to predicting the probability of transfusion requirement. [less ▲]

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See detailApparent changes of the Ordovician-Mississippian plant diversity
Cascales-Miñana, Borja ULg

in Review of Palaeobotany and Palynology (in press)

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See detailNa2FePO4F/multi-walled carbon nanotubes for lithium-ion batteries: Operando Mössbauer study of spray-dried composites
Brisbois, Magali; Caes, Sébastien ULg; Sougrati, M.T. et al

in Solar Energy Materials & Solar Cells (in press)

In order to favor electronic conductivity in sodium iron fluorophosphate electrodes for lithium- or sodium-ion batteries, composites of Na2FePO4F with multi-walled carbon nanotubes (CNTs) were prepared by ... [more ▼]

In order to favor electronic conductivity in sodium iron fluorophosphate electrodes for lithium- or sodium-ion batteries, composites of Na2FePO4F with multi-walled carbon nanotubes (CNTs) were prepared by pilot-scale spray drying. Addition of multi-walled CNTs in the solution results in an excellent dispersion of the CNTs within the volume of Na2FePO4F and not only at the surface of the particles. Following a heat treatment at 600°C in argon in order to reach crystallization, X-ray diffraction and ex situ Mössbauer spectroscopy revealed the presence of significant amounts of Fe(III) and maghemite (γ-Fe2O3) in the powder. However, Na2FePO4F/CNTs composites exhibit good electrochemical performance when cycling against lithium, with a discharge capacity of 104mAhg-1 at C/10 rate and 90mAhg-1 at 1C rate. Therefore, operando 57Fe transmission Mössbauer spectroscopy analyses were carried out in order to investigate the evolution of the iron oxidation state during cycling. During the first discharge, all the Fe(III) is reduced to Fe(II), explaining the good electrochemical performance. [less ▲]

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See detailScalable temperature induced stress for the large-scale production of functionalized Bifidobacteria
Nguyen, Huu Thanh ULg; Razafindralambo, Hary; Richel, Aurore ULg et al

in Journal of Industrial Microbiology & Biotechnology (in press)

The application of sub-lethal stresses is known to be an efficient strategy to enhance survival of probiotic bacteria during drying processes. In this context, we previously showed that the application of ... [more ▼]

The application of sub-lethal stresses is known to be an efficient strategy to enhance survival of probiotic bacteria during drying processes. In this context, we previously showed that the application of heat stress upon the entry into stationary phase increased significantly the viability of Bifidobacterium bifidum. However, this heat shock has been considered only in small scale bioreactor and no information is available for a possible scaling-up strategy. Five different operating scales (0.2 L, 2 L, 20 L, 200 L and 2000 L) have thus been tested and the results showed that the viability of B. bifidum increases from 3.15 to 6.57 folds, depending on the scale considered. Our observations pointed out the fact that the heat stress procedure is scalable according to the main outcome, i.e. increases in cell viability, but other factors have to be taken into account. Among these factors, dissolved carbon dioxide seems to play a significant role since it explain the differences observed between the test performed at lab-scale and in industrial conditions. [less ▲]

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See detailReal-time measurement of temperature variation during nanosecond pulsed laser induced contamination deposition
Kokkinos, Dimitrios ULg; Gailly, Patrick ULg; Georges, Marc ULg et al

in Applied Optics (in press)

In this paper a study of the heat generation during UV Laser Induced Contamination (LIC) and potentially resulting subsequent thermal damage is presented. This becomes increasingly interesting when optics ... [more ▼]

In this paper a study of the heat generation during UV Laser Induced Contamination (LIC) and potentially resulting subsequent thermal damage is presented. This becomes increasingly interesting when optics with delicate coatings are involved. During LIC radiation can interact with outgassing molecules both in the gas phase and at the surface, triggering chemical and photo-fixation reactions. This is a major hazard, in particular for laser units operating under vacuum conditions such as for space applications. The intense photon flux not only affects the contaminant deposition rate but also alters their chemical structure that can increase their absorption coefficient. Over cumulative irradiation shots these molecules formed deposits that increasingly absorb photons and produce heat as a by-product of de-excitation eventually leading to thermal damage. One could better asses the risk of the latter with the knowledge of temperature during the contamination process. For this purpose thermoreflectance technique is used here to estimate the temperature variation from pulse to pulse during contamination deposition through the analysis of a temperature-dependent surface reflectance signal. [less ▲]

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See detailBrabantophyton, a new genus with stenokolealean affinities from a Middle to earliest Upper Devonian locality from Belgium
Momont, Nicolas ULg; Gerrienne, Philippe ULg; Prestianni, Cyrille

in Review of Palaeobotany and Palynology (in press)

A new taxon with stenokolealean affinities, Brabantophyton runcariense gen. et sp. nov., is described from seven pyrite permineralized axes collected from the mid Givetian to earliest Frasnian (late ... [more ▼]

A new taxon with stenokolealean affinities, Brabantophyton runcariense gen. et sp. nov., is described from seven pyrite permineralized axes collected from the mid Givetian to earliest Frasnian (late Middle to earliest Upper Devonian) locality of Ronquières (Belgium). The specimens include stems and lateral organs. The stems are characterized by a protostele dissected into three primary ribs, each of them dividing into two secondary ribs. The protostele shows a central protoxylem strand and numerous strands distributed along the midplanes of the ribs. The vascular supply to lateral organ is composed of two pairs of traces, produced at the same time by the two ribs issued from a single primary rib of the protostele. Within each pair, the shape and the size of the traces are unequal: one is T-shaped and the other is oval to reniform. The T-shaped traces of each pair face each other. The inner cortex of the lateral organs is parenchymatous and the outer cortex is sparganum-like. The specimens of Brabantophyton runcariense show many similarities with the stenokolealean genus Crossia virginiana Beck and Stein, but the vascular supply of lateral organs of the latter consists of a more symmetrical and distinctively simpler pair of traces. Brabantophyton represents the first report of the Stenokoleales in southeastern Laurussia. The characteristics of the Brabantophyton protostele compare better with the anatomy of the radiatopses, and, within the latter, particularly with basal seed plants. [less ▲]

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See detailLarge deviation spectra based on wavelet leaders
Bastin, Françoise ULg; Esser, Céline ULg; Jaffard, Stéphane ULg

in Revista Matemática Iberoamericana (in press)

We introduce a new multifractal formalism, based on distributions of wavelet leaders, which allows to detect non-concave and decreasing multifractal spectra, and we investigate the properties of the ... [more ▼]

We introduce a new multifractal formalism, based on distributions of wavelet leaders, which allows to detect non-concave and decreasing multifractal spectra, and we investigate the properties of the associated function spaces. [less ▲]

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See detailActive Management of Low-Voltage Networks for Mitigating Overvoltages due to Photovoltaic Units
Olivier, Frédéric ULg; Aristidou, Petros ULg; Ernst, Damien ULg et al

in IEEE Transactions on Smart Grid (in press)

In this paper, the overvoltage problems that might arise from the integration of photovoltaic panels into low-voltage distribution networks is addressed. A distributed scheme is proposed that adjusts the ... [more ▼]

In this paper, the overvoltage problems that might arise from the integration of photovoltaic panels into low-voltage distribution networks is addressed. A distributed scheme is proposed that adjusts the reactive and active power output of inverters to prevent or alleviate such problems. The proposed scheme is model-free and makes use of limited communication between the controllers, in the form of a distress signal, only during emergency conditions. It prioritizes the use of reactive power, while active power curtailment is performed only as a last resort. The behavior of the scheme is studied using dynamic simulations on a single low-voltage feeder and on a larger network composed of 14 low-voltage feeders. Its performance is compared to a centralized scheme based on the solution of an Optimal Power Flow problem, whose objective function is to minimize the active power curtailment. The proposed scheme successfully mitigates overvoltage situations due to high photovoltaic penetration and performs almost as well as the Optimal Power Flow based solution with significantly less information and communication requirements. [less ▲]

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See detailSafety in Long Term Radioactive Waste Management: Insight and Oversight
Schröder, Jantine; Rossignol, Nicolas ULg; Van Oudheusden, Michiel ULg

in Safety Science (in press)

High-level, long-lived radioactive waste remains hazardous for periods that go well beyond our human conception of time (many thousands of years). Because active safety measures are considered unreliable ... [more ▼]

High-level, long-lived radioactive waste remains hazardous for periods that go well beyond our human conception of time (many thousands of years). Because active safety measures are considered unreliable, unjustifiable and simply impossible over such long time spans, experts worldwide recommend geological disposal as the preferred strategy for long-term radioactive waste management, to a large extent due to its promise of delivering ‘passive safety’. Passive safety refers to the repository being safe ‘by itself’, i.e. unmediated by human actors and actions. Safety is thus approached technically and delineated as an intrinsic property of the disposal system. As such, the notion of 'passive safety' entails a system simplification that allows for approaching safety in a more calculable and predictable manner than would be the case for 'active safety'. In this article, we describe and analyze the ambiguity of this seemingly straightforward approach to safety. Drawing on constructivist insights from safety science and science and technology studies, we propose a more integrated sociotechnical vision that transcends the active versus passive safety division. The notion of 'oversight', as it is currently starting to surface in international radioactive waste management discourses, will be used as a sensitizing concept, offering potential to elaborate such an integrated vision. [less ▲]

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