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See detailCrop association to improve aphid biological control
Chevalier Mendes Lopes, Thomas ULg; Bosquée, Emilie ULg; Bodson, Bernard ULg et al

Poster (2014, August)

This research focused on the development of sustainable alternative methods to control aphids, giving special emphasis on cultural practices and plant management systems. Increasing the diversity within ... [more ▼]

This research focused on the development of sustainable alternative methods to control aphids, giving special emphasis on cultural practices and plant management systems. Increasing the diversity within crops may have several beneficial effects on pest control, creating attractive habitats for indigenous beneficial fauna and simultaneously deterring pests (“push-pull” approach). In this field study, two wheat/pea associations (mixed cropping and strip cropping) where compared to monocultures of pea and wheat. The abundance and diversity of adult aphidophagous beneficials (predators and parasitoids) were accessed weekly, using yellow traps, while aphids were observed directly on plants. All individuals were identified down to the level of species. In both crops, the percentage of aphid infestation and density of colonies were significantly higher in monocultures during the abundance periods. The mixing was particularly beneficial for the pea, while strip cropping was more efficient for the wheat. Concerning beneficials, their abundance was also significantly higher in monocultures, comparing with the other treatments. This study shows that increasing diversity within crops can prevent them from aphid infestations. However, additional methods are needed to attract more efficiently the aphidophagous beneficials, in order to promote the natural control of aphids. [less ▲]

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See detailAnisotropic resistivity tensor of melt-cast Bi2212 superconductors from QTA
Dellicour, Aline ULg; Vertruyen, Bénédicte ULg; Lutterotti, Luca et al

Conference (2014, August)

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See detailEvaluation of the performance of an experimental somnolence quantification system in terms of reaction times and lapses
François, Clémentine ULg; Wertz, Jérôme ULg; Kirkove, Murielle ULg et al

in Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (2014, August)

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See detailAssessment of pulmonary hypertension in dogs with chronic pulmonary diseases by thoracic ct-angiography.
Couvreur, T.; Roels, Elodie ULg; Merveille, Anne-Christine ULg et al

in Proceedings of the ECVDI Meeting, Utrecht - Netherlands - 27-30 August 2014 (2014, August)

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See detailde Mérode (Prince Werner)
Genin, Vincent ULg; Philippe de Schoutheete de Tervarent

in Nouvelle Biographie Nationale (2014)

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See detailTranscriptomics and Proteomics of a Secondary Green Alga.
Perez, Emilie ULg; Lapaille, Marie; Degand, Hervé et al

Poster (2014, August)

Euglena gracilis is a secondary green alga related to trypanosomes that derives from a secondary endosymbiosis between a phagotrophic ancestor and a prasinophycean green alga. Our general objective is to ... [more ▼]

Euglena gracilis is a secondary green alga related to trypanosomes that derives from a secondary endosymbiosis between a phagotrophic ancestor and a prasinophycean green alga. Our general objective is to study the metabolic interactions established between the secondary plastid and the mitochondrion after the endosymbiotic event and to determine the phylogenetic origin of the genes encoding the proteins involved in the energetic pathways. As a first step, we analysed the subunit composition of the mitochondrial respiratory chain, both in silico and by targeted proteomics, to assess the extent of its similitude with the respiratory chain of Trypanosomatidae. We have shown that Euglena shares many additional subunits with trypanosomes, which suggests that these subunits are not especially associated to a parasitic lifestyle. As a second step, we sequenced the total transcriptome of Euglena and determined the phylogenetic origin of each predicted transcript using a database of about 1000 complete proteomes representing the diversity of life. These analyses confirmed that Euglena recruited its genes from a very diverse set of sources. As a third step, we performed a high-throughput analysis of the mitochondrial proteome of Euglena. Our MS/MS experiments, taking advantage of the availability of our transcriptome, mostly recovered mitochondrial proteins, which indicates that our mitochondrial extracts were quite pure. The identified proteins encompassed about 15 different mitochondrial pathways. We are now in the process of comparing the expression levels of both the transcripts and the corresponding proteins across a range of culture conditions selected to differently stimulate the mitochondrion and the plastid. [less ▲]

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See detailCase studies of incorporation of prior information in electrical resistivity tomography: comparison of different approaches
Caterina, David ULg; Hermans, Thomas ULg; Nguyen, Frédéric ULg

in Near Surface Geophysics (2014), 12(4), 451-465

Many geophysical inverse problems are ill-posed and their solution non-unique. It is thus important to reduce the amount of mathematical solutions to more geologically plausible models by regularizing the ... [more ▼]

Many geophysical inverse problems are ill-posed and their solution non-unique. It is thus important to reduce the amount of mathematical solutions to more geologically plausible models by regularizing the inverse problem and incorporating all available prior information in the inversion process. We compare three different ways to incorporate prior information for electrical resistivity tomography (ERT): using a simple reference model or adding structural constraints to Occam's inversion and using geostatistical constraints. We made the comparison on four real cases representing different field applications in terms of scales of investigation and level of heterogeneities. In those cases, when electromagnetic logging data are available in boreholes to control the solution, it appears that incorporating prior information clearly improves the correspondence with logging data compared to the standard smoothness constrain. However, the way to incorporate it may have a major impact on the solution. A reference model can often be used to constrain the inversion; however, it can lead to misinterpretation if its weight is too strong or the resistivity values inappropriate. When the computation of the vertical and/or horizontal correlation length is possible, the geostatistical inversion gives reliable results everywhere in the section. However, adding geostatistical constraints can be difficult when there is not enough data to compute correlation lengths. When a known limit between two layers exists, the use of structural constrain seems to be more indicated particularly when the limit is located in zones of low sensitivity for ERT. This work should help interpreters to include their prior information directly into the inversion process through an appropriate way. [less ▲]

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See detailQuality of Work Life, Burnout, and Stress in Emergency Department Physicians: A Qualitative Review
Bragard, Isabelle ULg; Dupuis, Gilles; Fleet, Richard

in European Journal of Emergency Medicine (2014)

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See detailCompeting Latin American Regionalisms in a changing world
Santander, Sébastian ULg

in Telò, Mario (Ed.) European Union and New Regionalism. (2014)

Collective ambitions in Latin America (LA) go hand in hand with the processes of independence and the creation of States. Since the 19th century, the continent has experienced wave after wave of different ... [more ▼]

Collective ambitions in Latin America (LA) go hand in hand with the processes of independence and the creation of States. Since the 19th century, the continent has experienced wave after wave of different types of regionalism: the ‘Bolivarian’ joint project, ‘introverted’ regional associations and ‘open’ regionalism. LA’s ‘left-turn’ has given rise to a new wave of regional projects. Described by some as post-liberal, these projects have also seen changes. Shared ambitions have therefore continued to be at the heart of the political debate of LA decision-makers. Nonetheless, while LA regionalism is a constant over time, it is still a work-in-progress. Its nature keeps evolving, based on changes in the domestic and international political context. As a political phenomenon, regionalism covers a dynamic and shifting reality. This reality can move forward, slow down or move backwards, as this comparative analysis of LA regional organisations (ROs) shows. These changes can also be the result of competition between these projects. We will also see that, while regionalisms are the result of a political will of their own, they can also be fashioned by external actors’ strategies. The US’s penchant for bilateralism and the EU’s role as an active promoter of international regionalism all affect these collective LA projects. Thus, this paper does not just aim to study regionalism in a comparative way but also to situate it in its links with international relations (IR). The article is structured in three parts. The first aims to study the structural nature of regionalism in LA. To do so, a comparative analysis of the different regional initiatives is suggested, plus a look at the impact from outside factors and actors. This approach will also allow us to bring out the similarities and differences between the different waves of regionalism, to understand what has been achieved and the lessons learnt from old projects in order to better grasp the specificity and nature of current regional initiatives. Our last point will focus on the implications of LA and global geopolitical changes for the new regionalism in LA. [less ▲]

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See detailIdentification and Characterization of a Halotolerant, Cold-Active Marine Endo-β-1,4-Glucanase by Using Functional Metagenomics of Seaweed-Associated Microbiota
Martin, Marjolaine ULg; Biver, Sophie ULg; Steels, Sébastien ULg et al

in Applied and Environmental Microbiology (2014), 80(16), 4958-4967

A metagenomic library was constructed from microorganisms associated with the brown alga Ascophyllum nodosum. Functional screening of this library revealed 13 novel putative esterase loci and two ... [more ▼]

A metagenomic library was constructed from microorganisms associated with the brown alga Ascophyllum nodosum. Functional screening of this library revealed 13 novel putative esterase loci and two glycoside hydrolase loci. Sequence and gene cluster analysis showed the wide diversity of the identified enzymes and gave an idea of the microbial populations present during the sample collection period. Lastly, an endo-β-1,4-glucanase having less than 50% identity to sequences of known cellulases was purified and partially characterized, showing activity at low temperature and after prolonged incubation in concentrated salt solutions. [less ▲]

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See detailPhénologie et intensité de la migration postnuptiale diurne en Ardenne du nord-est par le suivi migratoire (Ramecroix, 2006 à 2010)
Beckers, Arnaud ULg; Baron, André

in Aves (2014), 51(2), 87-106

We present the results of five years of monitoring postnuptial migration in the northeast Ardennes (the Ramecroix site) from 2006 to 2010. The timing and intensity of migration have been calculated for ... [more ▼]

We present the results of five years of monitoring postnuptial migration in the northeast Ardennes (the Ramecroix site) from 2006 to 2010. The timing and intensity of migration have been calculated for the 19 commonest species. Phenology for each species varied markedly from year to year. The passage of two particular species (Northern Lapwing and Song Trush) was extremely concentrated in time. Comparison with data from the Netherland and from Les Awirs (Liège, Belgium) show differences between locations, for which we propose some explanations. The full dataset constitute a useful benchmark for future studies on the spatial variability of migration flow. [less ▲]

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See detailRural Credit and Farms Efficiency : Modelling Farmers Crédit Allocation Decisions, Evidences from Benin
Sossou, Comlan ULg; Noma, Freddy; Yabi, Jacob

in Economics Research International (2014), 2014

This paper analyses farmers’ credit allocation behaviors and their effects on technical efficiency. Data were collected from 476 farmers using themultistage sampling procedure.The stochastic frontier ... [more ▼]

This paper analyses farmers’ credit allocation behaviors and their effects on technical efficiency. Data were collected from 476 farmers using themultistage sampling procedure.The stochastic frontier truncated-normal with conditional mean model is used to assess allocation schemes effects on technical efficiency. Tobitmodel reveals the impact of farmers’ sociodemographic characteristics on efficiency scores. Results reveal that farm revenue (about 2,262,566 Fcfa on average) is positively correlated with land acreage, quantity of labour, and costs of fertilizers and insecticides. Farmers’ behaviors respond to six schemes which are categorized in two allocations contexts : out-farm and in-farm allocations. The model shows that only scheme (e) positively impacts technical efficiency.This scheme refers to the decision to invest credit to purchase better quality of pesticides, herbicides, fertilizers, and so forth. The positive effect of the scheme (c) may be significant under conditions of farmers’ education level improvement. Then, scheme (e) is a better investment for all farmers, but effect of credit allocation to buy agricultural materials is positive only for educated farmers. Efficiency scores are reduced by household size and gender of the household head. Therefore a household with more than 10 members and a woman as head is likely to not be technically efficient. [less ▲]

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See detailHow to simulate quickly and efficiently a flow over a spillway ?
Goffin, Louis ULg; Erpicum, Sébastien ULg; Dewals, Benjamin ULg et al

Conference (2014, August)

Flows over hydraulic structures, such as weirs or spillways, can be modelled using different techniques. New models such as SPH or PFEM are becoming more and more popular. These models are particle and/or ... [more ▼]

Flows over hydraulic structures, such as weirs or spillways, can be modelled using different techniques. New models such as SPH or PFEM are becoming more and more popular. These models are particle and/or meshless and consequently require a lot of computational power. Other methods such as VOF also require a lot of computational time. In the frame of 2-D vertical flows, other techniques use much less computation time. For irrotationnal flows, solving the Laplace equation can be done very efficiently. The difficulty of this method lies in the definition of boundary conditions. The free-surface, which is naturally determined when using Lagrangian methods, needs a heavy iterative solving due to its non-linear nature when expressed in the frame of the Laplace equation. This paper will present an original technique that allows a quicker and easier determination of the free-surface. An irregular mesh for boundaries is used and discussed. The method is validated with analytical solutions and experimental measurements. [less ▲]

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See detailCT FEATURES OF A LACRIMAL GLAND TUMOR IN A DOG
Etienne, Anne-Laure ULg; Grauwels, Magda ULg; Storms, Goedele ULg et al

Poster (2014, August)

Background: In the dog, neoplasms of the lacrimal gland are rare. Lacrimal cysts were also reported. Computed tomography (CT) scan findings of these lacrimal gland abnormalities have not been described in ... [more ▼]

Background: In the dog, neoplasms of the lacrimal gland are rare. Lacrimal cysts were also reported. Computed tomography (CT) scan findings of these lacrimal gland abnormalities have not been described in dogs. Purpose: The present report describes clinical and CT features of a lacrimal gland tumor in a dog. Methods: A 3,5 year old female intact Leonberger with a good general health status was presented with a progressive swelling at the level of the supero-temporal area of the left upper eyelid and of the bulbar conjunctiva since 3 weeks. Ocular examination revealed a slight enophthalmia and a ventronasal strabismus, the presence of a firm mass in the upper eyelid which was anteriorly well circumscribed and extending posteriorly between the globe and the orbital ligament. Findings: A CT scan pre- and post- contrast studies of the head were performed. A 3 cm hypoattenuating (+/- 10 HU) ovoid mass was observed dorsolateral to the indented left globe. This mass was well circumscribed by an unevenly thick irregular soft tissue- attenuating wall (50HU), which was strongly contrast-enhanced (150HU) and measured about 2 to 10mm in thickness. The left globe was displaced caudoventromedially. No adjacent bone lesion, or foreign body was observed. No normal left lacrimal gland was observed. These findings were suggestive of an abscess or an orbital tumor with a necrotic/cystic center; a lacrimal cyst was considered less likely because of the unevenness and the thickness of the wall. Complete surgical ablation was done by a modified lateral orbitotomy. Histopathology revealed a mixed benign tumor of the lacrimal gland and a lymphocytic necrotic adenitis. Six months postoperatively no recurrence is noted and the tear production is 15mm/min. Conclusion: The lacrimal gland is located dorsolateral to the globe and produces tears. In human medicine, a wide range of lacrimal gland pathologies were described and assessed by computed imaging techniques. Pleomorphic adenomas (mixed benign tumor) could reveal irregular bone erosion and could undergo malignant transformation. In dogs, lacrimal cysts were described as thin walled structures.4 Only few articles reported lacrimal gland tumor. To the authors knowledge, CT findings of a lacrimal gland tumor have not been described previously. In conclusion, lacrimal gland tumor should be included in the differential diagnosis of a firm ovoid cystic/necrotic mass dorsolateral to the orbit. [less ▲]

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See detailRelaxations for multi-period optimal power flow problems with discrete decision variables
Gemine, Quentin ULg; Ernst, Damien ULg; Louveaux, Quentin ULg et al

in Proceedings of the 18th Power Systems Computation Conference (PSCC'14) (2014, August)

We consider a class of optimal power flow (OPF) applications where some loads offer a modulation service in exchange for an activation fee. These applications can be modeled as multi-period formulations ... [more ▼]

We consider a class of optimal power flow (OPF) applications where some loads offer a modulation service in exchange for an activation fee. These applications can be modeled as multi-period formulations of the OPF with discrete variables that define mixed-integer non-convex mathematical programs. We propose two types of relaxations to tackle these problems. One is based on a Lagrangian relaxation and the other is based on a network flow relaxation. Both relaxations are tested on several benchmarks and, although they provide a comparable dual bound, it appears that the constraints in the solutions derived from the network flow relaxation are significantly less violated. [less ▲]

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See detailLe rôle des chemins de fer. La ligne de chemin de fer Stavelot-Malmedy : construction, inauguration et expérience de guerre
Bechet, Christophe ULg

in Lensen, Jean-Pierre (Ed.) 1914-1918. Visé. Une Cité Martyre au coeur de la Grande Guerre (2014)

Cet article s'attarde non seulement sur les préparatifs belges de sabotage des lignes de chemin de fer en 1914, mais également sur les conséquences de ces destructions pour la logistique allemande. L ... [more ▼]

Cet article s'attarde non seulement sur les préparatifs belges de sabotage des lignes de chemin de fer en 1914, mais également sur les conséquences de ces destructions pour la logistique allemande. L'auteur se focalise notamment sur la ligne de chemin de fer Stavelot-Malmedy à proximité du camp d'Elsenborn dont le sabotage ne fut pas à la hauteur des espérances belges. Pendant la guerre ce débouché ferroviaire fut particulièrement surveillé par le réseau d'espionnage de Dieudonné Lambrecht. [less ▲]

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See detailDetection of nitric oxide by diaminofluorescein visualizes the skeleton in living zebrafish.
Renn, Jörg ULg; Pruvot, Benoist; Muller, Marc ULg

in Journal of Applied Ichthyology (2014), 30(4), 701706

Several in vivo stainings, such as Calcein, Alizarin Red and Quercetin are commonly used to visualize ossification in living teleost specimen. These staining techniques represent important tools for bone ... [more ▼]

Several in vivo stainings, such as Calcein, Alizarin Red and Quercetin are commonly used to visualize ossification in living teleost specimen. These staining techniques represent important tools for bone research in fish, but do not visualize cartilage. In the present study, we show that nitric oxide (NO) labelling by DAF-FM DA visualizes both bone and cartilage in vivo during zebrafish skeletogenesis. NO detection performed in Tg(osterix:mCherry) or in combination with Alizarin Red in wild-type zebrafish reveals that intense staining through NO labelling colocalizes with the appearance of osteoblasts and characterizes ossified structures. Cartilage structures are clearly distinguished in the living larvae, although the labelling is less intensive when compared to ossified structures. This method is the first and easy to handle alternative to cartilage and bone double stainings on fixed samples. In contrast to most live skeletal stainings, which only stain the mineralized bone structures, this protocol in addition allows in vivo visualization of cartilage. [less ▲]

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