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See detailSpatial diversification of agroecosystems towards biological control of insect pests: A focus on intercropping and wildflower strips
Hatt, Séverin ULg

Doctoral thesis (2017)

Facing the limits of input-intensive agriculture, agroecology aims at thinking ways to design a sustainable agriculture that is economically viable and socially relevant. It notably invites to mobilize ... [more ▼]

Facing the limits of input-intensive agriculture, agroecology aims at thinking ways to design a sustainable agriculture that is economically viable and socially relevant. It notably invites to mobilize ecological processes within agroecosystems in order to enhance the delivery of ecosystem services towards reducing the use of external inputs – among others insecticides. For enhancing biological control of insect pests, a strategy is to spatially diversify agroecosystems at the field scale. Whereas increasing plant diversity could directly negatively affect pest development on the one hand (i.e. bottom-up effect), providing flowering features could allow the enhancement of natural enemies and their direct effect on pest populations on the other hand (i.e. top-down effect). The present thesis focused on intercropping (i.e. the cultivation of at least two crop species simultaneously in a same field) as a way to diversify crop habitat, and the sowing of wildflower strips as a non-crop feature. A systematic analysis of the literature revealed that, in most of studies, wheat (Triticum aestivum L.)-based intercropping allows a reduction of insect pests on crops, without necessarily favouring their natural enemies, compared to pure-stands. Besides, the provision of flowering resources, by for instance sowing wildflower strips, can attract and support flower visiting predators and parasitoids. Hence, in a first set of field experiments, combining the two tactics of increasing crop diversity and providing flowering resources was tested. First in China, wheat crop was associated with oilseed rape (Brassica napus L.), but it neither allowed reducing aphid (Hemiptera: Aphididae) abundance nor enhancing their natural enemies compared to pure stands. Instead, aphid density – independently from the treatments – affected natural enemy abundance, and interspecific relations between aphids and their natural enemies were observed. Second in Belgium, wildflower strips were sown within a wheat field, which led to a reduction of aphid density in wheat plots in between flowering features and an increase of aphidophagous hoverflies (Diptera: Syrphidae) compared to pure-stand wheat. Nevertheless, the presence of flowering strips did not affect the other natural enemies, i.e. lacewings (Neuroptera: Chrysopidae), ladybeetles (Coleoptera: Coccinellidae) and parasitoid wasps (Hymenoptera: Braconidae). Therefore, a second set of field experiments focussed on ways to compose mixtures of wild flowers attractive to a diversity of natural enemies. Flower functional traits were considered due to their effect on insect behaviour. First, the hypothesis that mixtures with high functional diversity attract and support a high abundance and diversity of aphid flower visiting predators was tested. This hypothesis was not verified. Instead, the high density in the plots of some flower species (especially the Asteraceae Leucanthemum vulgare Lam.) known to be attractive to flower visitors was supposed to have overwhelmed the effect of functional diversity. Second, a methodology was developed to identify which flower traits significantly affect natural enemy abundance – in this experiment parasitoids of oilseed rape beetle pests (i.e. Meligethes spp. [Coleoptera: Nitidulidae] and Ceutorhynchus spp. [Coleoptera: Curculionidae]) – in flower mixtures. Among seven traits, visual traits (i.e. colour, ultra-violet reflectance) and the one related to food availability (i.e. corolla morphology) were found to significantly affect parasitoid abundance. These results highlight that (i) increasing plant diversity at the field scale can – but not systematically – favour a reduction of insect pests, (ii) including flowering features can enhance some – but not all – of their natural enemies, and (iii) in order to compose flower mixes attractive to natural enemies, specific flower traits – rather than functional diversity at the mixture level – can be considered. These results are discussed in a broader perspective. Indeed, strategies to spatially diversify crop and non-crop habitats in agroecosystems are various, as well as the ways to compose, manage and design such habitats. Also, processes at larger scales than the field may be determinant. Moreover, insects are not the only pests, and pests are not the only biotic or abiotic elements that need to be regulated in agroecosystems. Controlling multiple pests simultaneously but also enhancing the provision of multiple regulating services represent challenges for future research in agriculture. [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 detailUntangling glycaemia and mortality in critical care
Uyttendaele, Vincent ULg; Dickson, Jennifer L.; Shaw, Geoffrey M. et al

in Critical Care (2017), 21(1), 152

Background: Hyperglycaemia is associated with adverse outcomes in the intensive care unit, and initial studies suggested outcome benefits of glycaemic control (GC). However, subsequent studies often ... [more ▼]

Background: Hyperglycaemia is associated with adverse outcomes in the intensive care unit, and initial studies suggested outcome benefits of glycaemic control (GC). However, subsequent studies often failed to replicate these results, and they were often unable to achieve consistent, safe control, raising questions about the benefit or harm of GC as well as the nature of the association of glycaemia with mortality and clinical outcomes. In this study, we evaluated if non-survivors are harder to control than survivors and determined if glycaemic outcome is a function of patient condition and eventual outcome or of the glycaemic control provided. Methods: Clinically validated, model-based, hour-to-hour insulin sensitivity (SI) and its hour-to-hour variability (%ΔSI) were identified over the first 72 h of therapy in 145 patients (119 survivors, 26 non-survivors). In hypothesis testing, we compared distributions of SI and %ΔSI in 6-hourly blocks for survivors and non-survivors. In equivalence testing, we assessed if differences in these distributions, based on blood glucose measurement error, were clinically significant. Results: SI level was never equivalent between survivors and non-survivors (95% CI of percentage difference in medians outside ±12%). Non-survivors had higher SI, ranging from 9% to 47% higher overall in 6-h blocks, and this difference became statistically significant as glycaemic control progressed. %ΔSI was equivalent between survivors and non-survivors for all 6-hourly blocks (95% CI of difference in medians within ±12%) and decreased in general over time as glycaemic control progressed. Conclusions: Whereas non-survivors had higher SI levels, variability was equivalent to that of survivors over the first 72 h. These results indicate survivors and non-survivors are equally controllable, given an effective glycaemic control protocol, suggesting that glycaemia level and variability, and thus the association between glycaemia and outcome, are essentially determined by the control provided rather than by underlying patient or metabolic condition. [less ▲]

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See detailGreen Biotechnology in Belgium: The Ghent Innovation District.
Segers, Jean Pierre ULg

E-print/Working paper (2017)

This contribution explores the long-standing evolution of the green biotechnology cluster in the bioRegion of Flanders (Belgium), in particular in the Ghent innovation district.

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See detailDiametral dimension(s) and prominent bounded sets
Demeulenaere, Loïc ULg

Conference (2017, June 20)

The classical diametral dimension (Bessaga, Mityagin, Pelczynski, Rolewicz), denoted by "Delta", is a topological invariant which can be used to characterize Schwartz and nuclear locally convex spaces ... [more ▼]

The classical diametral dimension (Bessaga, Mityagin, Pelczynski, Rolewicz), denoted by "Delta", is a topological invariant which can be used to characterize Schwartz and nuclear locally convex spaces. Mityagin also introduced a variant of this diametral dimension, denoted by "Delta_b", using bounded sets in its definition, contrary to "Delta". In this talk, we present some conditions assuring the equality of these two diametral dimensions for Fréchet spaces. Among these conditions, there is the notion of existence of prominent bounded sets, due to Terzioglu. In fact, it appears that the existence of prominent sets is implied by the property "Omega Bar" of Vogt and Wagner. Finally, we describe a construction which gives Schwartz and nuclear non-Fréchet spaces E verifying "Delta_b(E) = \Delta(E)". [less ▲]

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See detailLe pouvoir politique des juges
Grandjean, Geoffrey ULg

Conference given outside the academic context (2017)

Notre société est marquée par un phénomène de judiciarisation qui voit une emprise croissante des juges dans les systèmes politiques et sociaux. Certains représentants n'hésitent d'ailleurs plus à ... [more ▼]

Notre société est marquée par un phénomène de judiciarisation qui voit une emprise croissante des juges dans les systèmes politiques et sociaux. Certains représentants n'hésitent d'ailleurs plus à fustiger le « gouvernement des juges ». Quels pouvoirs les juges exercent-ils dans nos systèmes démocratiques ? Pour répondre à cette question, il est proposé de présenter les trois grandes fonctions politiques des juges : 1) la production de normes, 2) l'arbitrage de valeurs morales et 3) la stabilisation du système politique. Ces trois fonctions sont autant de déclinaisons du pouvoir politique des juges qui concrétisent un nouvel équilibre entre les pouvoirs. De nombreuses décisions de jurisprudence illustrent le propos. [less ▲]

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See detailGeneralized Pascal triangles for binomial coefficients of finite words
Stipulanti, Manon ULg

Conference (2017, June 19)

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word ... [more ▼]

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word. Similarly to the Sierpiński gasket that can be built as the limit set, for the Hausdorff distance, of a convergent sequence of normalized compact blocks extracted from Pascal triangle modulo 2, we describe and study the first properties of the subset of [0, 1] × [0, 1] associated with this extended Pascal triangle modulo a prime p. Then we create a new sequence from this extended Pascal triangle that counts, on each row of this triangle, the number of positive binomial coefficients. We show that this sequence is 2-regular. To extend our work, we construct a Pascal triangle using the Fibonacci representations of all the nonnegative integers and we define the corresponding sequence of which we study the regularity. This regularity is an extension of the classical k-regularity of sequences. [less ▲]

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See detailGeneralized Pascal triangles for binomial coefficients of finite words
Stipulanti, Manon ULg

Conference (2017, June 16)

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word ... [more ▼]

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word. Similarly to the Sierpiński gasket that can be built as the limit set, for the Hausdorff distance, of a convergent sequence of normalized compact blocks extracted from Pascal triangle modulo 2, we describe and study the first properties of the subset of [0, 1] × [0, 1] associated with this extended Pascal triangle modulo a prime p. Then we create a new sequence from this extended Pascal triangle that counts, on each row of this triangle, the number of positive binomial coefficients. We show that this sequence is 2-regular. To extend our work, we construct a Pascal triangle using the Fibonacci representations of all the nonnegative integers and we define the corresponding sequence of which we study the regularity. This regularity is an extension of the classical k-regularity of sequences. [less ▲]

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See detailFrammenti d’intonaci di I stile a Ostia Antica. Un lotto inedito proveniente dagli strati preparatori di un mosaico tardo-repubblicano (Domus dei Bucrani - Camera dei Nani)
Morard, Thomas ULg; Motta, Lucie ULg

Conference (2017, June 16)

Les fouilles entreprises durant les années 2002-2010 sur le site de la Schola del Traiano (IV, IV, 15) à Ostia Antica ont révélé l’existence d’une domus tardo-républicaine - la Domus aux Bucranes (60-20 ... [more ▼]

Les fouilles entreprises durant les années 2002-2010 sur le site de la Schola del Traiano (IV, IV, 15) à Ostia Antica ont révélé l’existence d’une domus tardo-républicaine - la Domus aux Bucranes (60-20 av. J.-C.) - dont le système décoratif de IIe style (pavements, enduits peints et reliefs de stuc, plafonds) est apparu exceptionnellement bien conservé dans les couches les plus profondes de la parcelle urbaine concernée. Ce système décoratif - actuellement en cours de publication - a déjà été présenté à la communauté scientifique lors de différents colloques et journées d’études internationales. Il n’est pas question d’y revenir dans le cadre de la prochaine rencontre de l’AIRPA. En revanche, nous souhaiterions y présenter un lot d’enduits peints de Ier style jetés pêle-mêle dans les couches de préparation du tapis de mosaïque de la Chambre des Nains - un oecus aménagé durant les années 40-30 au sein de cette même domus tardo-républicaine. Restés inédits jusqu’à ce jour, ces fragments comptent parmi les plus anciens jamais découverts à Ostia Antica et leur position stratigraphique - scellée entre deux pavements bien datés - offre à n’en pas douter matière à réflexion. L’ensemble de ces fragments a fait l’objet d’une documentation systématique et des analyses archéométriques ont été portées sur les mortiers et les pigments des éléments les plus significatifs. Ce sont les résultats de cette entreprise scientifique que nous souhaiterions présenter lors du colloque de l'Aquileia afin de pouvoir intégrer cet ensemble décoratif de Ier style dans un corpus plus large - une mise en relation étroite avec le matériel contemporain découvert dans le Latium. [less ▲]

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See detailThe "Death" of Restorative Justice Advisers in Belgian Prisons
Dubois, Christophe ULg

Scientific conference (2017, June 15)

This presentation accounts for three dimensions enlightening 20 years of RJ within Belgian Prisons: the policy-making process, the policy-implementation process, and the policy and organizational ... [more ▼]

This presentation accounts for three dimensions enlightening 20 years of RJ within Belgian Prisons: the policy-making process, the policy-implementation process, and the policy and organizational embeddedness of RJ in Belgian prison settings. [less ▲]

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See detailDevelopment of an open-source algorithm based on inertial measurement units (IMU) of a smartphone to detect cattle grass intake and ruminating behaviors
Andriamandroso, Andriamasinoro ULg; Lebeau, Frédéric ULg; Beckers, Yves ULg et al

in Computers & Electronics in Agriculture (2017), 139

In this paper, an open algorithm was developed for the detection of cattle’s grass intake and rumination activities. This was done using the widely available inertial measurement unit (IMU) from a ... [more ▼]

In this paper, an open algorithm was developed for the detection of cattle’s grass intake and rumination activities. This was done using the widely available inertial measurement unit (IMU) from a smartphone, which contains an accelerometer, a gyroscope, a magnetometer and location sensors signals sampled at 100 Hz. This equipment was mounted on 19 grazing cows of different breeds and daily video sequences were recorded on pasture of different forage allowances. After visually analyzing the cows’ movements on a calibration database, signal combinations were selected and thresholds were determined based on 1-s time windows, since increasing the time window did not increase the accuracy of detection. The final algorithm uses the average value and standard deviation of two signals in a two-step discrimination tree: the gravitational acceleration on x-axis (Gx) expressing the cows’ head movements and the rotation rate on the same x-axis (Rx) expressing jaw movements. Threshold values encompassing 95% of the normalized calibrated data gave the best results. Validation on an independent database resulted in an average detection accuracy of 92% with a better detection for rumination (95%) than for grass intake (91%). The detection algorithm also allows for characterization of the diurnal feeding activities of cattle at pasture. Any user can make further improvements, for data collected at the same way as the iPhone’s IMU has done, since the algorithm codes are open and provided as supplementary data. [less ▲]

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See detailLa ligue d'Action française: mode d'organisation et pratiques culturelles, sociales et politiques (1905-1936)
Schmidt, Anne-Catherine ULg

Doctoral thesis (2017)

Notre thèse se décline en une approche chronologico-thématique autour de trois pôles majeurs. Il s'agit, tout d'abord d'une démonstration qui entend établir un tableau aussi précis que possible de la ... [more ▼]

Notre thèse se décline en une approche chronologico-thématique autour de trois pôles majeurs. Il s'agit, tout d'abord d'une démonstration qui entend établir un tableau aussi précis que possible de la structure, des rouages et de l'implantation des organisations d'AF à Paris et en province. L'objectif est ensuite d'analyser les grandes matrices de l'engagement militant mais aussi et surtout leurs évolutions successives en lien avec un contexte politico-diplomatique extrêmement mouvant. Il s'agit pour chaque période donnée de chercher à comprendre ce qui constitue l'engagement au sein de la ligue dans une approche résolument tournée vers la base militante. Enfin, il faut réfléchir à la place et au rôle de l'AF dans la nébuleuse royaliste et nationaliste de son temps afin de comprendre les jeux d'alliance et de concurrence entre les diverses organisations mais aussi dans quelle mesure et de quelle manière la ligue d'AF s'est intégrée au répertoire d'action collective de son temps tout en participant à son renouvellement. Le choix de notre découpage chronologique répond à des nécessités à la fois contextuelles et propres à l'histoire de l'Action française. Au cours de la première période, de 1905 à 1914, on assiste à une structuration rapide et continue de l'appareil d'action intellectuelle et militante. Les rouages nationaux et locaux de la ligue se mettent en place et les matrices de l'engagement militant sont diffusées par l'intermédiaire du quotidien et contribuent à influencer l'opinion publique. A cette époque, l'AF est presque seule dans le champ nationaliste mais doit se positionner au sein du monde royaliste. Pendant la Grande Guerre, les structures de la ligue sont désorganisées. L'objectif principal est alors de continuer à diffuser le journal ce qui n'empêche pas la ligue d'utiliser le temps de guerre pour tenter de nouvelles méthodes de propagande notamment dans l'armée. La période 1914-1918 permet aussi à l'AF de se respectabiliser en choisissant la voie de l'Union sacrée. Elle reste malgré tout une organisation particulièrement surveillée d'autant plus que son influence dans l'opinion publique s'accroît. Après-guerre, l'AF se réorganise partout en province. Au cours de la période 1919-1926, elle fait l'expérience de la vie parlementaire et glisse, de fait, vers une sorte de conservatisme contre lequel elle s'est initialement constituée. Ses échecs électoraux couplés à l'influence croissante des communistes dans la vie publique contribuent à relancer son activisme militant mais pas suffisamment selon certains de ses membres qui suivent alors Georges Valois dans la dissidence du Faisceau. L'AF doit également faire face à l'apparition d'une nouvelle concurrence nationaliste avec la naissance des Jeunesses Patriotes. En 1926, elle est confrontée à la plus grave crise de son histoire : sa condamnation pontificale. Au cours de la période 1927-1929, la ligue cherche à rebondir et à maintenir son implantation et ses activités dans un contexte, par ailleurs, globalement défavorable. Les résultats sont extrêmement nuancés selon les régions mais, dans l'ensemble, il n'y a pas d'écroulement de sa structure militante même si les difficultés financières de la ligue sont de plus en plus importantes. Au tournant des années 1930, la crise économique aggrave encore ces difficultés mais contribue aussi à créer un contexte favorable à un nouvel épisode de flambée ligueuse. Au cours de la période 1933-1936, l'AF connaît un regain de vitalité dont le paroxysme se situe au moment du 6 février 1934. Cela étant, cet épisode démontre également les limites et les faiblesses du phénomène ligueur nationaliste en France. [less ▲]

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See detailGFR and drug dosage adaptation: are we still in the mist?
DELANAYE, Pierre ULg

Conference (2017, June 13)

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