References of "2014"
     in
Bookmark and Share    
Peer Reviewed
See detailTuta absoluta (Lepidoptera: Gelechiidae) ability to localize and develop on wild and cultivated solanaceous plant species
Bawin, Thomas ULiege; Dujeu, David ULiege; Fagan, Maud ULiege et al

Conference (2014, December 13)

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is a widespread invasive species damaging economically important cultivated solanaceous crop plants, including tomatoes and potatoes. Little ... [more ▼]

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is a widespread invasive species damaging economically important cultivated solanaceous crop plants, including tomatoes and potatoes. Little is known about the ability of this microlepidoptera to encounter and develop on alternative wild and agricultural plant species. These plants could provide refuges and have to be identified for more efficient integrated management strategies. In the present study, we assessed the ability of T. absoluta to develop on wild (Solanum nigrum, Atropa belladonna, Datura stramonium) and cultivated (Solanum tuberosum) solanaceous plant species under laboratory conditions. Fitness tests were performed in Petri dishes by isolating single individuals with excised leaf from one of the host plants. We found that Solanum species allowed higher larval survivability and shorter development time (from egg to adult emergency) compared to the other plants. Two choice behavioral assays performed in flying tunnels (S. tuberosum versus another plant) revealed that adult distribution and female oviposition did not differ between Solanum species, which were preferred to the other tested plants. These results appeared to be consistent with survival rates and development times. Because larval survivability depends on the female’s oviposition choice, the hypothesis that host plant choice is influenced by plant volatile organic compounds has to be tested. It can be concluded that Solanum species remain the more suitable hosts for T. absoluta development among the tested plants. Other plant species could be opportunistically colonized with little incidence but care should be taken in these results as genetic variability in insects and plants, as well as plant physiological state, might have an impact on the pest survivabilty. [less ▲]

Detailed reference viewed: 114 (34 ULiège)
See detailMédias et éditorialistes belges en temps de crise : quels discours face aux politiques d'austérité ?
Geuens, Geoffrey ULiege

Conference given outside the academic context (2014)

Detailed reference viewed: 86 (14 ULiège)
Full Text
See detailDetection of rRNA synthesis sites within reptilian nucleoli
Bartholomé, Odile ULiege; Thiry, Marc ULiege; Franck, Claire

Poster (2014, December 13)

Detailed reference viewed: 39 (8 ULiège)
Peer Reviewed
See detailWildlife Conservation Practitioners' skills : between official goals and real practices
Denayer, Dorothée ULiege

Conference (2014, December 13)

Detailed reference viewed: 9 (1 ULiège)
See detailCopropriété, superficie et emphytéose
Lecocq, Pascale ULiege

Scientific conference (2014, December 13)

Detailed reference viewed: 85 (14 ULiège)
Full Text
See detailNew technologies in conservation: monitoring African wildlife with UAS
Linchant, Julie ULiege; Semeki, Jean; Lejeune, Philippe ULiege et al

Conference (2014, December 13)

In the vast protected areas of Africa, traditional wildlife surveys performed by plane or foot are logistically difficult to implement due to the lack of means and appropriate materials. Moreover, the ... [more ▼]

In the vast protected areas of Africa, traditional wildlife surveys performed by plane or foot are logistically difficult to implement due to the lack of means and appropriate materials. Moreover, the possibilities of encountering poachers in the field pose a serious risk to the monitoring teams. Over the last decade, civilian UAS (Unmanned Aerial Systems) boomed in natural resource monitoring. One of the biggest challenges of the UAS is to replace traditional wildlife censuses for the application of wildlife conservation. Parameters have to be approached in a different way than before. We performed test flights in the open savannah of the Garamba National Park during the wet season using the Falcon Unmanned UAS. Both photos (Sony Nex7, 24Mp) and videos, including thermal infrared videos (Tamarisk 640x480), have been used. Flight altitude ranged from 50 to 200m and pictures showed that animals can be effectively detected at 100m. We spotted elephants, hippopotamus and buffaloes as well as other smaller species such as hartebeests, kobs and warthogs. Thermal videos gave medium quality results during the day due to the heat but performed well during the night. The limited range and endurance of the UAS suggest a rethink of the usual census protocols. We therefore tested new flight plans in a rosette shape to take advantage of the higher points in the park, with transects having the length of the maximal range. Twelve transects of 10km can be covered in half a day with pictures covering a 15.6km² area. Human activities could also be detected. Pictures showed areas burned by poachers and the thermal infrared camera allows the detection of fires from a high altitude. Future developments need to be investigated such as automatic detection to review the huge amount of data collected and statistical methods must be adapted to those challenging situations. [less ▲]

Detailed reference viewed: 59 (14 ULiège)
Full Text
See detailLiquidity patterns on the US corporate bond market
Heck, Stéphanie ULiege; Margaritis, Dimitri; Muller, Aline ULiege

Conference (2014, December 13)

Liquidity commonality exists and empirical evidence (e.g. Lin et al., 2011) indicates that exposure to this common liquidity factor is priced in the cross-section of corporate bonds. The existence of ... [more ▼]

Liquidity commonality exists and empirical evidence (e.g. Lin et al., 2011) indicates that exposure to this common liquidity factor is priced in the cross-section of corporate bonds. The existence of commonality implies that part of a bond’s illiquidity is left as idiosyncratic. In this paper, we study how illiquidity components explain the cross-section of bond yields and how this relationship varies over time and across bond categories. We use a factor decomposition to break down total illiquidity into a common and an idiosyncratic component and analyze how yields relate differentially to each of these two components. We find that a bond’s idiosyncratic illiquidity is important, which might reflect informational asymmetries compounded by the lack of diversification in the institutional investors’ portfolios. Moreover, the relation between illiquidity and yield spreads appears to be negative during the recent crisis period. [less ▲]

Detailed reference viewed: 51 (9 ULiège)
Full Text
See detailEvaluation of two capture methods in the assessment of species richness of eusocial bees in Gabon
Fabre Anguilet, Edgard ULiege; Bengone Ndong, Toussaint; Francis, Frédéric ULiege et al

Poster (2014, December 13)

Detailed reference viewed: 26 (6 ULiège)
Full Text
Peer Reviewed
See detailDe quoi Radius est-il le nom? Enjeux et enseignements de la création d'une cellule de reporting institutionnel dans une université.
Hoerner, Céline ULiege; Bachelet, Jean-François ULiege

Conference (2014, December 13)

The contemporary university has to deal with an important pressure in order to adopt an operating and organisational system from the companies. The university is now encouraged to reconcile efficacy and ... [more ▼]

The contemporary university has to deal with an important pressure in order to adopt an operating and organisational system from the companies. The university is now encouraged to reconcile efficacy and financial viability goals in a competitive context between institutions. On the basis of a case study undertaken in a french--¿speaking Belgian university, we will think about the way dashboards and institutional reporting enable the university to respond to change injunctions, how they constitute a strategic management support, as well as the effects of their implementation in the administrative organisation. We will explain why Radius has been created at the university, its structure and how it works. We will see that its impact has been significant on the institution¿s staff. The creation of Radius, which aroused misgivings from administrations who have lost some of their prerogatives, reflects a shift of the administrative activity, whose part of the power is now concentrated in the hands of the authorities. [less ▲]

Detailed reference viewed: 71 (19 ULiège)
Full Text
Peer Reviewed
See detailStatic and dynamic mechanical response of different cork agglomerates
Tomé Jardin, Ruben Antonio ULiege; Fernandes, F.A.O.; Pereira, A.B. et al

in Materials and Design (2014), 68

Cork is a natural cellular material capable of withstanding considerable amounts of energy and exhibiting a viscoelastic return to its original shape. This feature is particularly interesting to resist to ... [more ▼]

Cork is a natural cellular material capable of withstanding considerable amounts of energy and exhibiting a viscoelastic return to its original shape. This feature is particularly interesting to resist to successive impacts. In this study, the behavior of different types of agglomerated cork (AC) and expanded cork (EC) is investigated under static and dynamic loadings. Double impact was carried out on the samples using a hemispheric actuator. The peak acceleration data for all compounds were further analyzed. Static compression tests gave an interesting insight into the stress–strain curve of agglomerates and Poisson’s ratio variation during deformation. Results demonstrate a clear influence of agglomerated density and grain size on the resulting mechanical properties and point out a tremendous potential for this sustainable material to be tailored to fit diverse crashworthiness applications. [less ▲]

Detailed reference viewed: 31 (9 ULiège)
Full Text
Peer Reviewed
See detailSound production in piranhas and relatives: preliminary results
Melotte, Geoffrey ULiege; Michel, Christian ULiege; Parmentier, Eric ULiege

Poster (2014, December 12)

Acoustic communication plays an important role in the life of many teleost species where it is mainly involved in agonistic and/or courtship behaviour(s). Despite the large number of species in the family ... [more ▼]

Acoustic communication plays an important role in the life of many teleost species where it is mainly involved in agonistic and/or courtship behaviour(s). Despite the large number of species in the family Serrasalmidae (92 species), sound production has been described only in some of them, particularly in the genera Serrasalmus and Pygocentrus. The aim of this study is to investigate the sound producing abilities of different Serrasalmidae species and to understand the corresponding mechanisms. Two herbivorous species of Serrasalmidae, Piaractus brachypomus and Metynnis lippincottianus, produce sounds composed of a single pulse. The mechanism involved in these species is not yet understood. In contrast, the calls emitted by several species of Serrasalmus and Pygocentrus are harmonic sounds composed of several pulses without inter-pulse interval. Their mechanism results from the forced vibration of the swimbladder following the contraction of sonic muscles that are attached to tendons surrounding ventrally the bladder. Another species, Pygopristis denticulata, is able to produce two types of sounds. The first sound consists of several pulses with irregular pulse period and is likely produced by a sonic muscle inserting on the skull and on the rostral part of the swimbladder. The second sound is multi-pulsed and, contrary to all other sounds described here, possesses a high dominant frequency suggesting a mechanism that does not involve the swimbladder and that remains to be determined. According to these results, Serrasalmidae seems to contain many species able to produce sounds by means of different mechanisms. [less ▲]

Detailed reference viewed: 79 (30 ULiège)
Full Text
Peer Reviewed
See detailA morphospace for the marine angelfishes (Pomacanthidae): patterns of diversity
Frederich, Bruno ULiege

Poster (2014, December 12)

The Pomacanthidae (marine angelfishes) is an iconic reef fish family of about 88 species. They have a circum-global distribution on tropical to warm-temperate reefs. Marine angelfishes occupy a diverse ... [more ▼]

The Pomacanthidae (marine angelfishes) is an iconic reef fish family of about 88 species. They have a circum-global distribution on tropical to warm-temperate reefs. Marine angelfishes occupy a diverse range of trophic niches, ranging from spongivory and algivory to zooplanktivory. Previous morpho-functional analysis of this family mainly focused on the head region and gut morphology in a limited number of species. However a morphological study including a large sample of angelfish representatives is currently lacking. Here, I explore the diversity of body morphology in this reef fish group. I collected x-ray images of 228 museum specimens from 71 species and I used landmark-based geometric morphometrics to quantify the overall body shape variation within this family. In a test for interspecific allometry, the linear regression of shape variables onto size (LogTL; TL = total length) was significant (P < 0.001). However, the percentage of explained variance in this model (23%) showed no strong relation between size and body shape. Main shape variation across species was explored using a principal component analysis on shape variables. The two main axes (PC1 and PC2) explained 74% of the total variance of the dataset. Pomacanthus spp., which mainly feed on fixed invertebrates (sponges and tunicates), have deep body with high and angular cephalic profile (lowest values along PC1). Conversely, the zooplanktivorous Genicanthus spp., those have a more pelagic lifestyle, show a slender body with shorter anal fin (highest values along PC1). The pigmy angelfishes from the genus Centropyge, which group different diets (omnivory or algivory), show a more robust and rectangular body shape (high scores along PC2). This work provides the row data for future studies dealing with the mode of phenotypic diversification of Pomacanthidae during evolution. [less ▲]

Detailed reference viewed: 77 (2 ULiège)
See detailLectures italiennes à Bruxelles (1500-1630)
Adam, Renaud ULiege

Scientific conference (2014, December 12)

Cette journée d’étude a pour but de favoriser les rencontres et échanges entre chercheurs de disciplines transversales autour de la problématique de la réception du livre italien dans les anciens Pays-Bas ... [more ▼]

Cette journée d’étude a pour but de favoriser les rencontres et échanges entre chercheurs de disciplines transversales autour de la problématique de la réception du livre italien dans les anciens Pays-Bas et en Principauté de Liège. Son objectif est d’étudier les mécanismes qui ont permis à l'édition en italien produite à la Renaissance d'être lue et divulguée dans ces territoires. Sous quelles formes ont circulé les livres italiens ? En langue originale ou en traductions (française et/ou néerlandaise) ? Quels itinéraires ont empruntés les livres « italiens » depuis le nord des Alpes ? Qui sont les acteurs de cette diffusion ? Dans quel(s) milieu(x) culturel(s) le livre italien a-t-il trouvé son public ? Existe-t-il un « italianisme bibliophilique » dans les anciens Pays-Bas et en Principauté de Liège ? Comment ont été conservés les livres italiens depuis le XVIe siècle jusqu’à nos jours ? L’ambition de cette manifestation est de contribuer à renouveler les connaissances sur la production, la diffusion et la conservation d’ouvrages « italiens » à la première modernité, ces vecteurs indispensables à l’essor de l’Humanisme et de la Renaissance dans l’Europe continentale. [less ▲]

Detailed reference viewed: 34 (9 ULiège)
Full Text
Peer Reviewed
See detailWhen microplastic is not microplastic: ingestion of artificial cellulose fibers by macrofauna living in seagrass macrophytodetritus
Collard, France ULiege; Remy, François ULiege; Gilbert, Bernard ULiege et al

Poster (2014, December 12)

Vagile macroinvertebrates associated with Posidonia oceanica exported litter were sampled in August 2011, November 2011 and March 2012 in the Calvi Bay (Corsica), near the STARESO oceanographic station ... [more ▼]

Vagile macroinvertebrates associated with Posidonia oceanica exported litter were sampled in August 2011, November 2011 and March 2012 in the Calvi Bay (Corsica), near the STARESO oceanographic station. Contents of digestive tracts were analyzed and fibers of various sizes and colors were found. Fibers were found in 27.6% of the digestive tracts in the nine dominant species. No correlation was found between number of fibers and taxonomic or trophic level. There were no seasonal or spatial preferences and thus we hypothesize that the organisms ingest these fibers randomly throughout the year. Analyses performed with a Raman spectroscope showed that these fibers were composed of cellulose associated with a coloring agent following the fiber color. Red fibers were dyed with the Direct Red 28, blue fibers were dyed with Direct Blue 22. Analyses by a scanning electron microscope (SEM) showed that cellulose fibers had the particular morphology of artificial cellulose fibers called: viscose. Our SEM analyses were compared to literature. This comparison assessed that fibers found in digestive tracts were made of viscose. In a first approach, viscose fibers looked like microplastic fibers because of their color and shape. However, it appeared that these fibers were made of artificial cellulose which is very different than plastic in terms of impacts and fate in the organisms. This study highlights the importance of physico-chemical analyses such as Raman spectroscopy and SEM to certainly identify the composition of particles ingested by organisms. From an ecological point of view, the red coloring agent is known to be carcinogenic in mammals and fish. Consequently, this pollution could provoke an environmental problem for the P. oceanica litter vagile macrofauna. [less ▲]

Detailed reference viewed: 232 (14 ULiège)
See detailPolitical and Social Thought at the Time of the Italian Wars: France and Burgundy
Dumont, Jonathan ULiege

Scientific conference (2014, December 12)

Detailed reference viewed: 10 (0 ULiège)