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See detailRadiative accidental matter
Da Silva Simoes, Catarina ULg; Aristizabal Sierra, Diego ULg; Wegman Ostrosky, Daniel ULg

in Journal of High Energy Physics [=JHEP] (2016)

Accidental matter models are scenarios where the beyond-the-standard model physics preserves all the standard model accidental and approximate symmetries up to a cutoff scale related with lepton number ... [more ▼]

Accidental matter models are scenarios where the beyond-the-standard model physics preserves all the standard model accidental and approximate symmetries up to a cutoff scale related with lepton number violation. We study such scenarios assuming that the new physics plays an active role in neutrino mass generation, and show that this unavoidably leads to radiatively induced neutrino masses. We systematically classify all possible models and determine their viability by studying electroweak precision data, bigbang nucleosynthesis and electroweak perturbativity, fi nding that the latter places the most stringent constraints on the mass spectra. These results allow the identi fication of minimal radiative accidental matter models for which perturbativity is lost at high scales. We calculate radiative charged-lepton flavor violating processes in these setups, and show that mu -> e gamma has a rate well within MEG sensitivity provided the lepton-number violating scale is at or below 5 105 GeV, a value (naturally) assured by the radiative suppression mechanism. Sizeable tau -> mu gamma branching fractions within SuperKEKB sensitivity are possible for lower lepton-number breaking scales. We thus point out that these scenarios can be tested not only in direct searches but also in lepton flavor-violating experiments. [less ▲]

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See detailHeavy methane to explain the unexplained recent methane growth ?
Bader, Whitney ULg; Strong, Kim; Walker, Kaley

Poster (2016, July)

Methane (CH4) is the second most important greenhouse gas emitted by human activities in the Earth’s atmosphere. Although it is roughly 200 times less abundant than carbon dioxide, it is a 28 times more ... [more ▼]

Methane (CH4) is the second most important greenhouse gas emitted by human activities in the Earth’s atmosphere. Although it is roughly 200 times less abundant than carbon dioxide, it is a 28 times more potent greenhouse gas. Approximately one fifth of the changes in the Earth’s balance energy caused by human-linked greenhouse gases since the beginning of industrialization (~1750) is due to methane. Methane is emitted by both natural sources and human activities. Indeed, methane can be emitted to the atmosphere through coal mining, oil and gas exploitation, rice cultures, domestic ruminant animals, biomass burning, waste management, wetlands, termites, methane hydrates and ocean. In the atmosphere, methane is mainly destroyed by the radical hydroxyl, also called the detergent of the atmosphere, and therefore plays a major role on the oxidizing capacity of the atmosphere. Since the beginning of the industrialization, atmospheric methane concentrations have increased by 260% to reach 1824 pbb in 2013. From the 1980s until the beginning of the 1990s, atmospheric methane was significantly on the rise, then stabilized during 1999-2006 to rise again afterwards. To this day, the source or sink responsible of this latter increase remains unexplained. Through each emission process, heavy molecules of methane (with one additional neutron either on a carbon or on one hydrogen atom) are emitted along methane (12CH4). The main heavy molecules of methane, called isotopologues (13CH4 and CH3D), are respectively ~110 and ~60 000 times less abundant than methane. Despite their small abundances, they give crucial information on the concentration of methane in the atmosphere and its evolution. Indeed, both isotopologues are emitted with specific emission ratio depending on the emission sources. Determining isotopic ratio of atmospheric methane is therefore a unique tracer of its budget. While the non-monotonous trend of methane is subject of an extensive number of studies, to our knowledge, no study of the isotopic ratio of methane derived from ground-based solar observations has been published to date. Measurements of heavy methane from Fourier Transform InfraRed spectra recorded with state of the art spectrometers installed at Eureka [Arctic, Canada] and Toronto [Ontario, Canada] along with analysis of observations collected by a portable instrument [Portable Atmospheric Research Interferometric Spectrometer for the Infrared, PARIS-IR], installed at Eureka will help fill this gap. Indeed, the produced time series, compared with the corresponding satellite observations (ACE-FTS) products will ease data interpretation and contribute to a global view of the question of isotopologues. [less ▲]

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See detailInternal structures of clusters in driven granular gas
Noirhomme, Martial ULg

Poster (2016, July)

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See detailCOST Action FA1407: Empowering NGS technologie for study and diagnostic of plant viruses
Massart, Sébastien ULg; Petter, François

Conference (2016, July)

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See detailTrophic interactions between two neustonic organisms: insights from Bayesian stable isotope data analysis tools
Lepoint, Gilles ULg; Laurent, Bernard; Gobert, Sylvie ULg et al

in Belgian Journal of Zoology (2016), 146(2), 123-133

The by-the-wind sailor Velella velella (Linnaeus, 1758) and its predator, the violet snail Janthina globosa (Swainson, 1822) are both floating neustonic organisms. Despite their global oceanic ... [more ▼]

The by-the-wind sailor Velella velella (Linnaeus, 1758) and its predator, the violet snail Janthina globosa (Swainson, 1822) are both floating neustonic organisms. Despite their global oceanic distribution and widespread blooms of V. velella in recent years, many gaps remain in our understanding about prey/predator interactions between these two taxa. Using stable isotope ratios of carbon and nitrogen, we aimed to study the trophic relationship between V. velella and J. globosa and investigate diet variation of V. velella and J. globosa in relation to individuals’ size. Bayesian approaches were used to calculate isotopic niche metrics and the contribution of V. velella to the J. globosa diet. Our data showed that the isotopic niche of V. velella differed markedly from that of J. globosa. It was larger and did not overlap that of the J. globosa, indicating a more variable diet but at a lower trophic level than J. globosa. The isotopic niche of V. velella also varied according to the size class of the individual. Small individuals showed a larger isotopic niche than larger animals and low overlap with those of the larger individuals. J. globosa displayed very low isotopic variability and very small isotopic niches. In contrast, there were no isotopic composition nor isotopic niche differences between J. globosa of any size. This very low isotopic variability suggested that J. globosa is a specialist predator, feeding, at least in this aggregation, principally on V. velella. Moreover, outputs of a stable isotope mixing model revealed preferential feeding on medium to large (> 500 mm2) V. velella colonies. While our isotopic data showed the trophic relationship between V. velella and J. globosa, many questions remain about the ecology of these two organisms, demonstrating the need for more fundamental studies about neustonic ecosystems. [less ▲]

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See detailGlobal changes, human activities and (re-) emerging of mosquito-borne pathogens: diversity, ecology and control of potential vectors
Boukraa, Slimane ULg

Doctoral thesis (2016)

Worldwide, mosquitoes (Diptera: Culicidae) are known as potential vectors of pathogens that cause infectious diseases, affecting both humans and animals, such as malaria, dengue, chikungunya, West Nile ... [more ▼]

Worldwide, mosquitoes (Diptera: Culicidae) are known as potential vectors of pathogens that cause infectious diseases, affecting both humans and animals, such as malaria, dengue, chikungunya, West Nile fever and dirofilariasis. In terms of morbidity and mortality, mosquitoes are considered as the most dangerous animals confronting mankind. Indeed, over three billion people live at risk of becoming infected by a mosquito-borne disease. Focus on mosquitoes has greatly increased not only in the tropic areas but also in the Palearctic region like Europe and Mediterranean areas. Researches on re-emerging vector-borne diseases are become a major issue in human and animal health worldwide, both in the North and South hemisphere. The spread in space and time of these many vector-borne diseases is strongly influenced by environmental factors (landscape, location and abundance of hosts and vectors, etc.) and climate (temperature, humidity, etc.) that influence population dynamics of the vector and the reservoir hots of pathogens. The acquisition of bio-ecological and taxonomic knowledges of mosquitoes is nevertheless an essential step for the understanding, preventing and management of current risks of the (re)-emergence of mosquito-borne parasites and mainly the preparation and prevention against future threats. The absence of vaccine and treatments against most of mosquito-borne diseases implies efficient vector control strategies, which are up to date mainly based on the use of chemical insecticides. However, most vectors develop resistance against currently used products whereas new chemical compounds was limited firstly by financial costs in research and development, and secondly by the toxicity of derivatives to human population, biodiversity, and environment. The exploitation of new methods, such as the use of microbial communities (mainly bacteria or entomopathogenic fungi) for vector control, will be therefore a promoted strategy at the global level. This doctoral thesis focuses on five main objectives: (i) to inventory and identify mosquito fauna in the livestock areas and their surroundings, especially in the equestrian farms; (ii) to study the population genetic structure of the potential vector complex Cx. pipiens s.l.; iii) to study the phylogeny and the origin of exotic mosquito species (Ae. albopictus & Ae. koreicus) as well as the potential tracks of their introduction; (iv) to know the bioecology and spatiotemporal dynamic of potential vectors; and finally (v) to suggest a biocontrol tool that can prevent and fight the proliferation of mosquitoes especially potential vectors and those causing nuisance problems. Obtained results in this thesis allowed highlighting identification and record of new mosquito species in the studied areas. It also allowed updating the list of mosquito fauna in the two countries, Belgium (31 species including three invasive mosquitoes) and Algeria (53 species including four new records form this research: Culex brumpti, Coquillettidia richiardii, Cq. Buxtoni and Uranotaenia balfouri). The phylogenetic analyses (COI and ND4) performed during this thesis allowed to confirm that Aedes koreicus and Ae. japonicas complex constitute two distinct species. In addition, given the phylogenetic analyses (COI and ND5 genes) and information about the origin of used tires inspected during this study in Belgium, Ae. albopictus was very probably reintroduced from the United States. In both Belgium and Algeria, this work permitted identifying and confirming the presence of different molecular forms of the Cx. pipiens complex: Cx. pipiens form pipiens, Cx. pipiens f. molestus as well as their hybrid form. Medical and veterinary importance of identified mosquito species and the risk of (re-)emerging of mosquito-borne diseases in Belgium and Algeria are discussed. Finally, the endosymbiont bacteria Pseudomonas seemed to be an interesting candidate for paratransgenic bacteria in order to reduce and/or inhibit the transmission of pathogens by mosquito vectors. [less ▲]

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

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

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

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

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

in Water Research (2016), 98

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

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

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See detailA comprehensive system of control characters for Ancient Egyptian hieroglyphic text in Unicode
Nederhof, Mark-Jan; Rajan, Vinodh; Lang, Johannes et al

Computer development (2016)

We propose a comprehensive system of control characters for encoding Ancient Egyptian hieroglyphs in Unicode.

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See detailTopology optimization for minimum weight with compliance and simpli ed nominal stress constraints for fatigue resistance
Collet, Maxime ULg; Bruggi, Matteo; Duysinx, Pierre ULg

in Structural and Multidisciplinary Optimization (2016)

This work investigates a simpli ed approach to cope with the optimization of preliminary design of structures under local fatigue constraints along with a global enforcement on the overall compliance. The ... [more ▼]

This work investigates a simpli ed approach to cope with the optimization of preliminary design of structures under local fatigue constraints along with a global enforcement on the overall compliance. The problem aims at the minimization of the weight of linear elastic structures under given loads and boundary conditions. The expected sti ness of the optimal structure is provided by the global constraint, whereas a set of local stress-based constraints ask for a structure to be fatigue resistant. A modi ed Goodman fatigue strength comparison is implemented through the same formalism to address pressure-dépendent failure in materials as in Drucker-Prager strength criterion. As a simplification, the Sines approach is used to de ne the equivalent mean and alternating stresses to address the fatigue resistance for an infinite life time. Sines computation is based on the equivalent mean and alternate stress depending on the invariants of the stress tensor and itsdeviatoric part, respectively. The so-called singularity phenomenon is overcome by the implementation of a suitable qp-relaxation of the equivalent stress measures. Numerical examples are presented to illustrate the features of the achieved optimal layouts and of the proposed algorithm. [less ▲]

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

in Talanta (2016), 154

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

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

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

Conference (2016, July)

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

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

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See detailReal-time capture of the folding-unfolding transitions in a single oligorotaxane foldamer
Sluysmans, Damien ULg; Hubert, Sandrine ULg; Bruns, Carson et al

Scientific conference (2016, July)

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

Conference (2016, July)

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

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

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See detailSolo vs. duet in different virtual rooms: On the consistency of singing quality across conditions
Fischinger, Timo; Kreutz, Gunter; Larrouy, Pauline ULg

Poster (2016, July)

Previous research on vocal pitch accuracy revealed insights into the fundamentals of singing. However, most of the research on singing focused on the analysis of single voices, whereas few aYempts have ... [more ▼]

Previous research on vocal pitch accuracy revealed insights into the fundamentals of singing. However, most of the research on singing focused on the analysis of single voices, whereas few aYempts have been made to tackle the challenge of analyzing mulTtrack recordings of singing ensembles. In addiTon, singers have to adjust their way of singing with respect to a given venue’s acousTcal environment (e.g., small room vs. a comparaTvely large space like a church). If it is common that musical performances are greatly influenced by room acousTcs, studies on the effects of room acousTcal features during ensemble singing are rare. In order to invesTgate singing performances across various condiTons, we manipulated the singing condiTon (unison, canon, solo) as well as the acousTcal feedback by applying diverging virtual rooms. Three duets with female singers (N = 6) were asked to sing three different melodies using headset microphones to record each singer separately. Recordings took place in the communicaTon acousTc simulator (CAS) at the House of Hearing (Oldenburg, Germany) to be able to provide different simulated acousTcal spaces (i.e., cathedral, classroom, and dry condiTon) to the singers. ObjecTve measures were performed on each recording and confirmed that the singers sang the melodies with high precision (small pitch interval deviaTons) hardly affected by singing condiTons or by the type of acousTcal feedback. However, the singers tended to driH (larger deviaTons of the tonal center) when singing in canon compared to solo and unison singing. Overall, the analysis of the pitch accuracy showed a general effect of condiTon (i.e., unison, canon, solo), but no general effect of acousTcal feedback and no interacTon between the two variables under study. [less ▲]

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See detailSoyons optimistes
RADERMECKER, Régis ULg

in Revue de l'Association Belge du Diabète (2016), 59(4), 3

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See detailPerception of pitch accuracy in melodies: A categorical or continuous phenomenon?
Larrouy, Pauline ULg; Franz, Simone; Poeppel, David

Conference (2016, July)

In western music, a semitone constitutes a theoretical and perceptual boundary between tones and is defined as a unit for categorical perception of intervals (Burns & Ward, 1978). However, melodic ... [more ▼]

In western music, a semitone constitutes a theoretical and perceptual boundary between tones and is defined as a unit for categorical perception of intervals (Burns & Ward, 1978). However, melodic perception does not rely exclusively on this category but also involves the notion of ‘correctness’. If we usually classify melodies as “in tune” or “out of tune” depending on the size of interval deviations (smaller than a semitone) along melodies, the transition between the two categories remains unclear. This study examines the process involved in pitch accuracy perception. Twenty-five participants identified melodies as “in tune” or “out of tune” and rated their confidence for each answer. The pitch manipulation consisted of the enlargement of an interval in 5 cent steps (from 0 to 50 cent deviation). The interval deviated was either a Major 2nd or a Perfect 4th and occurred in the middle or end of a 6-tone melody. The task was run twice, before and after an explicit definition of the two labels. Repeated measure ANOVAs were conducted to examine the effect of the deviation on the proportion of in- tune answers and on the confidence levels. For the participants who were able to learn the labels (n = 20), the proportion of in tune answers varies greatly according to the amplitude of the deviation and depended on the size of the interval manipulated. Associated with the confidence level measurement, the identification data support a categorical perception process. Interestingly, explicitly learning the labels increased the overall confidence but did not modify drastically the profile of the categories and the process behind the categorization. This study suggests that explicit learning is not necessary to develop higher order categories relative to “correctness”. Nevertheless, such a process seems limited to certain intervals. Further investigation of other intervals and individual differences seems promising to better understand the mechanisms underlying music perception. [less ▲]

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See detailLes mustères de la "Viege noire" ou comment se passe la demande d'allocation de handicap
Marquet, Françoise; RADERMECKER, Régis ULg

in Revue de l'Association Belge du Diabète (2016), 59(4), 9-13

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