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See detailImprovement of genetic evaluation systems for maternally influenced traits and multi-breed livestock populations
Vanderick, Sylvie ULg

Doctoral thesis (2017)

Animal breeding programs are designed to genetically improve livestock populations over many generations to enhance farm sustainability and competitiveness. Genetic improvement is achieved by selecting ... [more ▼]

Animal breeding programs are designed to genetically improve livestock populations over many generations to enhance farm sustainability and competitiveness. Genetic improvement is achieved by selecting genetically superior animals, based on estimated breeding values, to be the parents of the next generation. These estimated breeding values are calculated by solving mixed model equations characterizing appropriate statistical genetic evaluation models. To guarantee effective genetic selection, genetic evaluation models must be tailored to the specific characteristics of the traits and population under evaluation. This PhD thesis focused on the development of genetic evaluation models suitable for categorical maternally influenced traits and for multi-breed populations. Appropriate genetic animal models were developed and assessed: (1) for two categorical maternally influenced traits based on calving ease scores from Walloon Holstein dairy cattle and on lamb survival data from a New Zealand sheep population; (2) for two multi-breed populations based on milk yield records of New Zealand purebred and crossbred dairy cattle, and on purebred and crossbred calving ease scores from Walloon Belgian Blue and Holstein cattle. Results showed that (1) fitting maternal effects was required to avoid biasing the estimated breeding values, and there was no clear advantage in using non-linear mixed models instead of linear mixed models for the genetic analysis of the two categorical maternal traits studied; (2) breed-dependent breeding values could be estimated using the proposed multi-breed models, and that combining purebred and crossbred data had a positive influence on the accuracy of the breeding values of purebred animals. Finally, part of the research presented in this thesis contributed to the development of the genetic evaluation systems currently used in Walloon Region of Belgium and in New Zealand. [less ▲]

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See detailThe tax on legal entities in the light of civil law: a positive and prospective study of the income taxation for certain actors within the social economy
Garroy, Sabine ULg

Scientific conference (2017, April 21)

Dans le cadre de cette chaire Francqui, plusieurs doctorants belges ont eu l’occasion d’exposer leurs travaux et d’échanger avec le Pr. Dr. Dr.h.c. Wolfgang Schön, au cours de six classes d’excellence ... [more ▼]

Dans le cadre de cette chaire Francqui, plusieurs doctorants belges ont eu l’occasion d’exposer leurs travaux et d’échanger avec le Pr. Dr. Dr.h.c. Wolfgang Schön, au cours de six classes d’excellence dispensées à Liège et Anvers. [less ▲]

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See detailAnalyse Économique des Échanges Intra et Extracommunautaires de l'Union Économique et Monétaire Ouest-Africaine
Soma, Sassiémiké Abdoul Kader ULg

Doctoral thesis (2017)

Résumé de la thèse Le passage de l’Union Économique et Monétaire Ouest-Africaine (UEMOA) à une union douanière en janvier 2000 témoigne de la volonté des pays membres à promouvoir et à intensifier les ... [more ▼]

Résumé de la thèse Le passage de l’Union Économique et Monétaire Ouest-Africaine (UEMOA) à une union douanière en janvier 2000 témoigne de la volonté des pays membres à promouvoir et à intensifier les échanges commerciaux au sein de la zone. Plus de 15 ans après la création de ce vaste marché, les chiffres du commerce intra-communautaire ne sont guère encourageants. En effet, le ratio d’échanges intra-UEMOA stagne autour de 12%, nettement en dessous de ses échanges avec ses partenaires de l’UE et des 7 autres pays de la CEDEAO. La présente thèse a d’abord investigué le poids des barrières dans les échanges intra-UEMOA relativement à celles dans les échanges avec l’Europe et les autres pays de la CEDEAO. Les résultats montrent l’existence de plus de barrières dans les échanges avec l’UE et la CEDEAO que dans les échanges intra-UEMOA. Mieux, la faiblesse des échanges intra-communautaires doit être résorbée moins par la réduction des barrières dans les échanges mutuels que l’amélioration des facteurs d’offre et de demande. Ensuite, nous avons montré que la faiblesse des échanges intra-UEMOA est liée à leur mauvaise structure. En effet, les résultats montrent que les flux croisés de biens similaires entre pays de l’UEMOA sont faibles et leur augmentation permettrait non seulement de stimuler les échanges intra-communautaires, mais également de créer un effet multiplicateur du commerce sur la croissance. Enfin, après avoir analysé la dynamique de la croissance, du commerce et des investissements directs étrangers dans l’UEMOA, nous montrons que s’il existe une dynamique positive de long terme entre la croissance et le commerce, les IDE sont par contre défavorables à la croissance de long terme. Les recommandations vont dans le sens d’orienter davantage les IDE vers les secteurs de transformations capables de générer plus de productivité à long terme. [less ▲]

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See detail"888" Tweets on the Art and Science of Internet-Based Investing
Choffray, Jean-Marie ULg

E-print/Working paper (2017)

Here we are! Exactly “888” Tweets, regularly updated, on The Art and Science of Investing to “show you the way”, to share some observations on the evolution of the world, the behavior of the financial ... [more ▼]

Here we are! Exactly “888” Tweets, regularly updated, on The Art and Science of Investing to “show you the way”, to share some observations on the evolution of the world, the behavior of the financial markets, and to illustrate the key heuristics that I learned over the last twenty years. As, without any doubt, I am no Warren Buffett, feel free to disagree and develop you own “theory” of investing. Painful and solitary work... Success is at that price! And, based on what I did - and did not! - achieve, it shouldn’t be hard to do much better... That’s my wish for you! [less ▲]

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See detailExpanding chemistry's horizon with continuous-flow reactors - part II
Monbaliu, Jean-Christophe ULg

Conference (2017, April 20)

Continuous-flow micro- and mesofluidic reactors come with inherent properties that can be advantageously utilized for expanding the horizon of synthetic organic chemistry. Accurate control over local ... [more ▼]

Continuous-flow micro- and mesofluidic reactors come with inherent properties that can be advantageously utilized for expanding the horizon of synthetic organic chemistry. Accurate control over local process parameters, even under extreme conditions, inherent safety, production homogeneity and seamless scale-up are amongst the most important assets of continuous-flow chemistry. Besides, flow chemistry enables the design of efficient multistep processes with significantly reduced footprints. In this lecture, we will discuss some of the most fascinating aspects of continuous-flow micro- and mesofluidic reactors in the specific context of preparative organic chemistry. Multiple examples illustrating the development and implementation of continuous-flow multistep strategies for the synthesis of high-value added organic targets will be presented. [less ▲]

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See detailTriangles de Pascal et compagnie
Stipulanti, Manon ULg

Conference (2017, April 19)

Le triangle de Pascal classique ainsi que le triangle de Sierpiński sont des objets largement étudiés. Ils montrent des aspects auto-similaires et ont des liens avec les systèmes dynamiques, les automates ... [more ▼]

Le triangle de Pascal classique ainsi que le triangle de Sierpiński sont des objets largement étudiés. Ils montrent des aspects auto-similaires et ont des liens avec les systèmes dynamiques, les automates cellulaires, la théorie des nombres et les suites dites automatiques. Dans ce séminaire, nous présentons un travail en collaboration avec Julien Leroy et Michel Rigo. Dans un premier temps, nous introduisons une généralisation du triangle de Pascal basée sur les coefficients binomiaux de mots finis et nous étudions le cas plus particulier des représentations en base 2. Ces coefficients comptent le nombre de fois qu’un mot fini apparaît comme sous-suite d’un autre mot fini. De la même façon que le triangle de Sierpiński peut être construit comme l’ensemble limite, pour la distance de Hausdorff, d’une suite convergente de compacts renormalisés extraits du triangle de Pascal classique modulo 2, nous décrivons et étudions les premières propriétés du sous-ensemble de [0, 1] × [0, 1] associé à ce triangle de Pascal généralisé modulo un nombre premier p. Dans un second temps, nous étudions la suite qui compte, sur chaque ligne du triangle de Pascal généralisé en base 2, le nombre de coefficients binomiaux strictement positifs. Cette suite présente une régularité étonnante qui peut être mise en évidence en utilisant une structure particulière de graphes, appelée arbre des sous-mots. [less ▲]

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See detailL’insémination artificielle bovine : un traitement qui nécessite le constat d’oestrus. Comprendre pour agir.
Hanzen, Christian ULg

Conference given outside the academic context (2017)

Au cours de ces 70 dernières années d’utilisation de l’insémination artificielle (IA) (1946 année de naissance du premier veau issu de l’IA), la fertilité bovine n’a fait que décliner. Le taux de ... [more ▼]

Au cours de ces 70 dernières années d’utilisation de l’insémination artificielle (IA) (1946 année de naissance du premier veau issu de l’IA), la fertilité bovine n’a fait que décliner. Le taux de gestation était compris entre 44 et 48 % il y a 40 ans, elle est comprise entre 33 et 40 % actuellement. L’oestrus (dont la durée moyenne a également diminué au cours des années) constitue la phase clé de l’IA. Naturel ou induit, il constitue une étape indispensable à l’obtention d’une gestation. Ses caractéristiques hormonales et comportementales sont susceptibles d’être modifiées par de multiples facteurs inhérents à la production laitière ou à des pathologies liées au système reproducteur mais pas seulement. L’IA se définit comme une biotechnologie de la reproduction qui consiste à déposer un sperme de qualité au moyen d’une méthode et d’un matériel adéquat à l’endroit anatomique le plus approprié, au moment le plus opportun et d’une technique. Cet acte est tout sauf banal compte tenu des conséquences économiques importantes tant positives que négatives qu’il peut entraîner. Répondre à la question de savoir si la vache est « inséminable » n’est pas chose simple. Les moyens propédeutiques disponibles se sont avec le temps étoffés. Un état des lieux s’imposerait donc. A l’analyse de l’anamnèse et des symptômes et signes cliniques manifestés par la vache en oestrus, des stratégies hormonales ou non peuvent le cas échéant être mises en place. Encore convient-il d’en mesurer la pertinence. Au terme de la formation, l’apprenant sera capable de… - comprendre l’effet des facteurs hormonaux ou non susceptibles de modifier les manifestations oestrales et la fertilité - mettre en place le cas échéant des méthodes propédeutiques alternatives visant à confirmer ou non la décision d’inséminer une vache - décider du recours ou non à des stratégies thérapeutiques ou techniques pour augmenter le taux de gestation suite à une insémination [less ▲]

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See detailUse of a metagenetic approach to monitor the bacterial microbiota of “Tomme d’Orchies” cheese during the ripening process
Ceugniez, Alexandre; Taminiau, Bernard ULg; Coucheney, Françoise et al

in International Journal of Food Microbiology (2017), 247

The study of microbial ecosystems in artisanal foodstuffs is important to complete in order to unveil its diversity. The number of studies performed on dairy products has increased during the last decade ... [more ▼]

The study of microbial ecosystems in artisanal foodstuffs is important to complete in order to unveil its diversity. The number of studies performed on dairy products has increased during the last decade, particularly those performed on milk and cheese derivative products. In this work, we investigated the bacterial content of "Tomme d'Orchies" cheese, an artisanal pressed and uncooked French cheese. To this end, a metagenetic analysis, using Illumina technology, was utilized on samples taken from the surface and core of the cheese at 0, 1, 3, 14 and 21 days of ripening process. In addition to the classical microbiota found in cheese, various strains likely from environmental origin were identified. A large difference between the surface and the core content was observed within samples withdrawn during the ripening process. The main species encountered in the core of the cheese were Lactococcus spp. and Streptococcus spp., with an inversion of this ratio during the ripening process. Less than 2.5% of the whole population was composed of strains issued from environmental origin, as Lactobacillales, Corynebacterium and Brevibacterium. In the core, about 85% of the microbiota was attributed to the starters used for the cheese making. In turn, the microbiota of the surface contained less than 30% of these starters and interestingly displayed more diversity. The predominant genus was Corynebacterium sp., likely originating from the environment. The less abundant microbiota of the surface was composed of Bifidobacteria, Brevibacterium and Micrococcales. To summarize, the “Tomme d’Orchies” cheese displayed a high diversity of bacterial species, especially on the surface, and this diversity is assumed to arise from the production environment and subsequent ripening process. [less ▲]

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See detailAssessment of bacterial superficial contamination in classical or ritually slaughtered cattle using metagenetics and microbiological analysis
Korsak Koulagenko, Nicolas ULg; Taminiau, Bernard ULg; Hupperts, Caroline et al

in International Journal of Food Microbiology (2017), 247

The aim of this study was to investigate the influence of the slaughter technique (Halal vs. Classical slaughter) on the superficial contamination of cattle carcasses, by using traditional microbiological ... [more ▼]

The aim of this study was to investigate the influence of the slaughter technique (Halal vs. Classical slaughter) on the superficial contamination of cattle carcasses, by using traditional microbiological procedures and 16S rDNA metagenetics. The purpose was also to investigate the neck area to identify bacteria originating from the digestive or the respiratory tract. Twenty bovine carcasses (10 from each group) were swabbed at the slaughterhouse, where both slaughtering methods are practiced. Two swabbing areas were chosen: one “legal” zone of 1,600 cm2 (composed of zones from rump, flank, brisket and forelimb) and locally on the neck area (200 cm2). Samples were submitted to classical microbiology for aerobic Total Viable Counts (TVC) at 30°C and Enterobacteriaceae counts, while metagenetic analysis was performed on the same samples. The classical microbiological results revealed no significant differences between both slaughtering practices; with values between 3.95 and 4.87 log CFU/100 cm2 and 0.49 and 1.94 log CFU/100 cm2, for TVC and Enterobacteriaceae respectively. Analysis of pyrosequencing data showed that differences in the bacterial population abundance between slaughtering methods were mainly observed in the “legal” swabbing zone compared to the neck area. Bacterial genera belonging to the Actinobacteria phylum were more abundant in the “legal” swabbing zone in “Halal” samples, while Brevibacterium and Corynebacterium were encountered more in “Halal” samples, in all swabbing areas. This was also the case for Firmicutes bacterial populations (families of Aerococcaceae, Planococcaceae). Except for Planococcoceae, the analysis of Operational Taxonomic Unit (OTU) abundances of bacteria from the digestive or respiratory tract revealed no differences between groups. In conclusion, the slaughtering method does not influence the superficial microbiological pattern in terms of specific microbiological markers of the digestive or respiratory tract. However, precise analysis of taxonomy at the genus level taxonomy highlights differences between swabbing areas. Although not clearly proven in this study, differences in hygiene practices used during both slaughtering protocols could explain the differences in contamination between carcasses from both slaughtering groups. [less ▲]

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See detailVers une (r)évolution du renseignement belge : la nécessaire émergence d'une communauté du renseignement
Leroy, Patrick ULg

in Revue "Diplomatie" (2017)

Le renseignement belge entre dans une période de (r)évolution amenée par la crise des attentats qui secouent le sol européen. La tentations est grande pour les décideurs politiques de palier les "failles ... [more ▼]

Le renseignement belge entre dans une période de (r)évolution amenée par la crise des attentats qui secouent le sol européen. La tentations est grande pour les décideurs politiques de palier les "failles" du renseignement par des mesures radicales qui pourraient atteindre l'ADN, le coeur de métier du renseignement. [less ▲]

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See detailAtelier : ENMG de l'épaule
WANG, François-Charles ULg

Conference (2017, April 15)

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See detailExploration ENMG du plexus brachial
WANG, François-Charles ULg

Conference (2017, April 15)

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See detailExtracting residues from stone tools for optical analysis: towards an experiment-based protocol
Cnuts, Dries ULg; Rots, Veerle ULg

in Archaeological and Anthropological sciences (2017)

The identification of residues is traditionally based on the distinctive morphologies of the residue fragments by means of light microscopy. Most residue fragments are amorphous, in the sense that they ... [more ▼]

The identification of residues is traditionally based on the distinctive morphologies of the residue fragments by means of light microscopy. Most residue fragments are amorphous, in the sense that they lack distinguishing shapes or easily visible structures under reflected light microscopy. Amorphous residues can only be identified by using transmitted light microscopy, which requires the extraction of residues from the tool’s surface. Residues are usually extracted with a pipette or an ultrasonic bath in combination with distilled water. However, a number of researchers avoid residue extraction because it is unclear whether current extraction techniques are representative for the use-related residue that adheres to a flaked stone tool. In this paper, we aim at resolving these methodological uncertainties by critically evaluating current extraction methodologies. Attention is focused on the variation in residue types, their causes of deposition and their adhesion and on the most successful technique for extracting a range of residue types from the stone tool surface. Based on an experimental reference sample in flint, we argue that a stepwise extraction protocol is most successful in providing rep- resentative residue extractions and in preventing damage, destruction or loss of residue. [less ▲]

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See detailSubstrate Induced Strain Field in FeRh Epilayers Grown on Single Crystal MgO (001) Substrates
Barton, C. W.; Ostler, Thomas ULg; Huskisson, D. et al

in Scientific Reports (2017), 7

Equi-atomic FeRh is highly unusual in that it undergoes a rst order meta-magnetic phase transition from an antiferromagnet to a ferromagnet above room temperature (Tr ≈ 370 K). This behavior opens new ... [more ▼]

Equi-atomic FeRh is highly unusual in that it undergoes a rst order meta-magnetic phase transition from an antiferromagnet to a ferromagnet above room temperature (Tr ≈ 370 K). This behavior opens new possibilities for creating multifunctional magnetic and spintronic devices which can utilise both thermal and applied eld energy to change state and functionalise composites. A key requirement in realising multifunctional devices is the need to understand and control the properties of FeRh in the extreme thin lm limit (tFeRh < 10 nm) where interfaces are crucial. Here we determine the properties of FeRh lms in the thickness range 2.5–10 nm grown directly on MgO substrates. Our magnetometry and structural measurements show that a perpendicular strain eld exists in these thin films which results in an increase in the phase transition temperature as thickness is reduced. Modelling using a spin dynamics approach supports the experimental observations demonstrating the critical role of the atomic layers close to the MgO interface. [less ▲]

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See detailTowards Knowledge management in General Practice & Family Medicine; Guide to the indexing of master thesis.
Jamoulle, Marc ULg

Learning material (2017)

The Francophone Coordination Center for Training in General Practice (CCFFMG) (www.ccffmg.be)(French) is in charge of organizing the public release of the End-of-Study works (Master thesis) in General ... [more ▼]

The Francophone Coordination Center for Training in General Practice (CCFFMG) (www.ccffmg.be)(French) is in charge of organizing the public release of the End-of-Study works (Master thesis) in General Practice/Family Medicine (GP/FM) . This work is carried out at the end of the Master of Specialty of the Departments of General Practice of the Free University of Brussels (ULB), the Catholic University of Louvain (UCL) and the University of Liège (ULg). A dedicated website (www.mgtfe.be) offers an online copywriting guide. This site provides also a description and instruction manual for a GP/FM indexing system discussed in this document. This experimental system, based on the assembly of the International Classification of Primary Care, second version (ICPC-2), and a new contextual classification called Q-Codes version 2.5 is intended to help the manual indexation of the Master Thesis. The package, called Core Content Classification in GP/FM (3CGP), is now available in 8 languages (en-fr-nl-es-pt-vi-ko-tr) on the multilingual web site of Department of Medical Information and Medical Informatics (B2IM) of the University of Rouen (www.hetop.eu/q) together with a companion site (http://3cgp.woncaeurope.org) (in English). Family physician will be asked to choose a number of proposed codes to index their jobs at the time of online filing. The publishing site will be equipped with a search module based on the 3CGP indexing system. An evaluation of the system of indexing by the users is organized. [less ▲]

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See detailRevista "Esfera pública discursiva"
Becerra Mayor, David ULg

in Esfera pública discursiva (2017), 1

Número 1 de la revista de crítica e información literaria realizada por las y los estudiantes de "Stylistique et critique de l’espagnol moderne" del curso 2016-2017, de la Université de Liège.

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See detailEffects of various design parameters on system-level fire fragility functions for steel buildings
Elhami Khorasani, Negar; Gernay, Thomas ULg; Garlock, Maria

Conference (2017, April 07)

The existing literature in fire engineering is mostly based on single component study of structures, as opposed to system level building performance. In current practice, fire does not need to be ... [more ▼]

The existing literature in fire engineering is mostly based on single component study of structures, as opposed to system level building performance. In current practice, fire does not need to be considered as part of the structural design of the building. The required fire protection for steel components in a building is based on prescriptive design guidelines, which are based on standard fire tests on individual structural members. In addition, the fire-structure engineering has primary focused on deterministic analysis, while the field is moving towards performance-based design in recent years. Meanwhile, the scenarios leading to a fire event and the performance of the structure at elevated temperatures involve a great level of uncertainty. This work focuses on fire-structure interaction with the objective of developing fire fragility functions that capture fire damage uncertainty for the entire building (i.e., at the system-level). A fragility function provides the probability of exceeding a damage state for a given intensity measure of a given hazard. Fire fragility functions can be developed to measure the expected losses based on performance of a building structural system, rather than a single component. Different functions can be developed for buildings with different typologies (e.g. high-rise steel building with moment resisting frame, low rise steel building with bracing). This presentation derives fragility functions based on stochastic analyses of prototype buildings. In developing the fragility functions, uncertainties in the fire model, the heat transfer model and the thermo-mechanical response should be considered; but such a large number of random variables adds to the complexity of analysis and the computational time. Based on a sensitivity analysis for steel gravity frames, this work identifies the most important input parameters to be considered as random variables when developing fire fragility functions for an entire building. The sensitivity analysis for a multi-story steel building prototype is completed considering uncertainties at the compartment and building levels. At the compartment level, uncertainty in the fire scenario, compartment geometry, applied load, thermal and mechanical properties of steel and insulating materials are considered. At the building level, the influence of fire-resistance rating, building height, and occupancy type are studied. The results of this study identify the local and global parameters needed as part of deriving system-level fire fragility functions for a steel building. [less ▲]

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