References of "Compère, Philippe"
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See detailThe development of hearing abilities in the shark Scyliorhinus canicula
Parmentier, Eric ULiege; Banse, Marine ULiege; Boistel, Renaud et al

in American Journal of Anatomy (2020)

The few works on audition in sharks and rays concern only adult specimens. We report the hearing abilities in the dogfish Scyliorhinus canicula at different stages, from embryos that still have their yolk ... [more ▼]

The few works on audition in sharks and rays concern only adult specimens. We report the hearing abilities in the dogfish Scyliorhinus canicula at different stages, from embryos that still have their yolk sac inside their egg, to juveniles. Hearing development corresponds to an increase in the frequency range from 100−300 Hz in early pre-hatching stages to 100–600 Hz in juveniles. Modifications in hearing abilities correspond to the development of the brain, the increase of the volume of the membranous labyrinth, the growth of the sensory epithelium, and the development of stereocilia in addition to kinocilium before hatching. This work offers solid insights into the development of hearing abilities that usually can only be inferred from the anatomy of vertebrates or after birth/hatching. It shows also that shark can be sensitive to background noise during development. [less ▲]

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See detailMicrostructural and compositional variation in pacu and piranha teeth related to diet specialization (Teleostei: Serrasalmidae)
Delaunois, Yann ULiege; Huby, Alessia ULiege; Malherbe, Cédric ULiege et al

in Journal of Structural Biology (2020), 210

In any vertebrate group, tooth shape is known to fit with a biological function related to diet. However, little is known about the relationships between diet and tooth microstructure and composition in ... [more ▼]

In any vertebrate group, tooth shape is known to fit with a biological function related to diet. However, little is known about the relationships between diet and tooth microstructure and composition in teleost fishes. In this work, we describe the external morphology, internal microstructure and elemental composition of the oral teeth of three representative species of the family Serrasalmidae having different feeding habits (herbivorous vs. omnivorous vs. carnivorous). We used backscattered-electron imaging and low vacuum environmental scanning electron microscope to compare the organization and mineralization of tooth layers as well as energy dispersive X-ray microanalysis and Raman microspectrometry to investigate the elemental composition, Ca/P ratio and mineralogy of the most superficial layers. Oral teeth of each serrasalmid species have the same internal orga- nization based on five distinctive layers (i.e. pulp, dentine, inner enameloid, outer enameloid and cuticle) but the general tooth morphology is different according to diet. Microstructural and compositional variation of the cuticle and iron-enrichment of superficial layers were highlighted between herbivorous and carnivorous species. Iron is more concentrated in teeth of the herbivorous species where it is associated with a thicker cuticle ex- plaining the more intense red-pigmentation of the cutting edges of oral teeth. The iron-enrichment is interpreted as a substitution of Ca by Fe in the hydroxyapatite. These traits are discussed in the light of the evolutionary history of the family. Further considerations and hypotheses about the formation and origin of the mineralized tooth layers and especially the iron-rich superficial layers in teleost fishes are suggested. [less ▲]

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See detailBiodegradable cell microcarriers based on chitosan/polyester graft-copolymers
Demina, T. S.; Drozdova, M. G.; Sevrin, Chantal ULiege et al

in Molecules (2020), 25(8),

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See detailSoil and climate affect foliar silicification patterns and silica-cellulose balance in sugarcane (Saccharum officinarum)
de Tombeur, Félix ULiege; Vander Linden, C.; Cornelis, Jean-Thomas ULiege et al

in Plant and Soil (2020), 452(1-2), 529-546

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See detailLiquid dispensing in the adhesive hairy pads of dock beetles
Iazzolino, Antonio ULiege; Cerkvenik, Uros ULiege; Tourtit, Youness ULiege et al

in Journal of the Royal Society, Interface (2020), 17

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See detailReinforcement and adaptation of the mantis shrimp spike: how crustacean cuticle became a perfect harpoon?
Delaunois, Yann ULiege; Malherbe, Cédric ULiege; Tits, Alexandra ULiege et al

Conference (2019, September 10)

Introduction: In the field of bioinspired material, the crustacean cuticle is seen as an example of organo-mineral biomaterial able to endure strong stress thanks to the combination of fibrilar ... [more ▼]

Introduction: In the field of bioinspired material, the crustacean cuticle is seen as an example of organo-mineral biomaterial able to endure strong stress thanks to the combination of fibrilar organisation and mineral deposition. Stomatopoda is a crustacean order represented by two groups of species; smashing mantis shrimps and spearing mantis shrimps. Hence, the first group is already well studied for the mechanical abilities of their smashing limbs, this study will focus on the spearing mantis shrimps and their spearing appendage. These appendage present spikes able to impale fish in a fraction of second and are therefore designed to penetrate at high speed, to avoid escape of the prey but also to resist bending during the capture. Objective: The aim of this study is to determine how the mantis shrimp cuticle adapts its shape, internal organization and composition to endure the intense stress occurring during attacks. Materials and methods: Specimens of Lysiosquillina maculata were dissected and their spikes were conserved in ethanol or fixed with glutaraldehyde. The samples in ethanol were then embedded in resin and polished to be observed in µCTscan and SEM and analyzed by EDS and nanoindentation. Sample fixed in glutaraldehyde were contrast with OsO4 and embedded in resin to be observed in TEM. Results: Firstly, the µCTscan highlighted particular features in the external structure, the spike presenting serrations at its edges linked by grooves at its sides. It also show a curvature linked to the angle of attack of the mantis shrimp. But its internal organization also shows important rearrangements in comparison to the classic crustacean cuticle. These rearrangements affect even the arrangement of chitino-proteic fibers as the composition of the mineral. SEM-BSE and TEM observation highlight that the spike cuticle does not show a clear subdivision in the three classical layer found in arthropod cuticle i.e. endo-, exo, and epicuticle but consist in four layer with different organization. These layers are respectively called from the surface to the epidermis: the highly mineralized layer (HML), the outer helicoidal layer (OHL), the striated layer (STL) and the inner helicoidal layer (IHL). EDS analysis also shows that theses layers also present different composition and mineralization rate; the HML has the higher mineralization rate and is composed of flurapatite, the HML has the lower mineralization rate and is, as the OHL and STL, composed of a mix between calcium phosphate and calcium carbonate. The three innermost layers are also characterized by variation in the substitution rates of minor element as Na, K, Mg and F. Analysis of the spike cuticle with nanoindentation tests highlight variation in the reduced modulus between the layers. Conclusion: During its evolution, the spearing mantis shrimp has strongly modified its exoskeleton either in structure and mineral composition in order to perfectly suit its mechanical constraint. Variation of its internal organization seems to be adapted to endure with anisotropic stresses. On its side, modification of the composition in the mineral part raised its surface reduced modulus and hardness at value comparable with vertebrate teeth. Finally, by both structural and mineral variation, the cuticle spike is also thought to cope with cracks propagations. [less ▲]

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See detailNew insights on the paleobiology, biostratigraphy and paleogeography of the pre-Sturtian microfossil index taxon Cerebrosphaera
Cornet, Yohan ULiege; François, Camille; Compère, Philippe ULiege et al

in Precambrian Research (2019)

Important biological and geological events occurred during the early Neoproterozoic. Among diversifying eukaryotic assemblages, populations of the distinctive robust organic-walled vesicular microfossils ... [more ▼]

Important biological and geological events occurred during the early Neoproterozoic. Among diversifying eukaryotic assemblages, populations of the distinctive robust organic-walled vesicular microfossils (acritarchs) Cerebrosphaera occur as a short-lived taxon in several late Tonian to early Cryogenian worldwide successions. Here we report the first occurrence of this taxon in the Bouenza Subgroup (Republic of the Congo), enlarging its paleogeographic distribution and biostratigraphic significance. We also attempt to determine its biological affinities, using a combined analytical approach on specimens from the Kanpa and Hussar Formations, Australia, and from the Svanbergfjellet Formation, Spitsbergen. Morphological and quantitative analyses were performed using light microscopy and scanning electron microscopy, on more than 200 specimens and 9 specimens, respectively. The analyses show fine-scale morphological details and a morphological continuum between the former species Cerebrosphaera ananguae and Cerebrosphaera buickii, confirming their synonymy as proposed by a recently revised taxonomy. These observations also highlighted the presence of a previously mentioned envelope, formerly described and illustrated here for the first time. Ultrastructural analyses performed with TEM revealed two types of complex (bilayered and trilayered) wall ultrastructures. The molecular structure and thermal maturity of the organic walls estimated using Infrared and Raman microspectroscopies, reveal the highly aromatic composition of Cerebrosphaera’s wall biopolymer with short/highly branched aliphatic chains unlike known biopolymers. The complex morphology, ultrastructure and recalcitrant chemistry, combined with the large size of Cerebrosphaera confirm its eukaryotic nature. Comparison with possible modern analogues permits to suggest an affinity to stem metazoan eggs. This hypothesis is consistent with estimates from molecular clocks and, if confirmed, would provide an older evidence for stem metazoans than the Cryogenian biomarker and Ediacaran body fossil records. Our study reveals that Cerebrosphaera populations are important for the late Proterozoic biostratigraphy, but also participated to the Neoproterozoic diversification eukaryotes in connected oceans. [less ▲]

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See detailAstin C production by the endophytic fungus Cyanodermella asteris in planktonic and immobilized culture conditions
Vassaux, Antoine ULiege; Tarayre, Cédric; Arguelles Arias, Anthony ULiege et al

in Biotechnology Journal (2019)

The fungal endophyte Cyanodermella asteris was recently isolated from the medicinal plant Aster tataricus. This fungus produces astin C, a cyclic pentapeptide with anticancer and anti-inflammatory ... [more ▼]

The fungal endophyte Cyanodermella asteris was recently isolated from the medicinal plant Aster tataricus. This fungus produces astin C, a cyclic pentapeptide with anticancer and anti-inflammatory properties. The production of this secondary metabolite was compared in immobilized and planktonic conditions. For immobilized cultures, a stainless steel packing immersed in the culture broth was used as a support. In these conditions, the fungus exclusively grew on the packing, which provides a considerable advantage for astin C recovery and purification. C. asteris metabolism was different according to the culture conditions in terms of substrate consumption rate, cell-growth, and astin C production. Immobilized-cell cultures yielded a 30% increase of astin C production associate to a 39% increase in biomass. The inoculum type as spores rather than hyphae, and a pre-inoculation washing procedure with sodium hydroxide, turned out to be beneficial both for astin C production and fungus development onto the support. Finally, influence of culture parameters such as pH and medium composition, on astin C production was evaluated. With optimized culture conditions, astin C yield was further improved reaching a five times higher final specific yield compared to the value reported with astin C extraction from Aster tataricus (0.89 and 0.16 mg/g respectively). [less ▲]

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See detailSimultaneous production of two kinds of sounds in relation with sonic mechanism in the boxfsh Ostracion meleagris and O. cubicus
Parmentier, Eric ULiege; Solagna, Laura; Bertucci, Frédéric ULiege et al

in Scientific Reports (2019), 9

In fshes, sonic abilities for communication purpose usually involve a single mechanism. We describe here the sonic mechanism and sounds in two species of boxfsh, the spotted trunkfsh Ostracion meleagris ... [more ▼]

In fshes, sonic abilities for communication purpose usually involve a single mechanism. We describe here the sonic mechanism and sounds in two species of boxfsh, the spotted trunkfsh Ostracion meleagris and the yellow boxfsh Ostracion cubicus. The sonic mechanism utilizes a T-shaped swimbladder with a swimbladder fenestra and two separate sonic muscle pairs. Extrinsic vertical muscles attach to the vertebral column and the swimbladder. Perpendicularly and below these muscles, longitudinal intrinsic muscles cover the swimbladder fenestra. Sounds are exceptional since they are made of two distinct types produced in a sequence. In both species, humming sounds consist of long series (up to 45s) of hundreds of regular low-amplitude pulses. Hums are often interspersed with irregular click sounds with an amplitude that is ten times greater in O. meleagris and forty times greater in O. cubicus. There is no relationship between fsh size and many acoustic characteristics because muscle contraction rate dictates the fundamental frequency. We suggest that hums and clicks are produced by either separate muscles or by a combination of the two. The mechanism complexity supports an investment of boxfsh in this communication channel and underline sounds as having important functions in their way of life. [less ▲]

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See detailStudy of biological harpoon; microstructure of the mantis shrimp raptorial appendage
Delaunois, Yann ULiege; Compère, Philippe ULiege

Poster (2018, December 15)

Mantis shrimps (or Stomatopods) form one of the most surprising crustacean order in earth. Separated from decapods since Cretacean, species composing this group display unique features that makes them ... [more ▼]

Mantis shrimps (or Stomatopods) form one of the most surprising crustacean order in earth. Separated from decapods since Cretacean, species composing this group display unique features that makes them formidable marine benthic predators. In these features can be found the widest visual spectrum, a transformed telson used both as a shield and as a fin, an antennal pallet used as a rudder but also a pair of enhanced predatorial limbs. Two kinds of predatorial limbs exists, dividing mantis shrimps in two groups: smashing limbs used to brake carapaces and to knock out preys and spearing limbs used to impale fishes. Both these limbs are deployed at high speed thanks to their ability to store and release elastic energy and are reinforced to endure impacts. This study will focus on one spearing mantis shrimp, the striped mantis shrimp (Lysiosquillina maculata (Fabritius,1973)) and the cuticle of its raptorial appendage. The main goal is to understand how spines found in this appendage are internally arranged to face the mechanical stress that occurs when harpooning prey. Techniques as optical microscopy and scanning electron microscopy will allow to define how is arranged the cuticle found in the spine. Techniques of micro-analysis will then superimpose composition to the structural information. These analyses highlight a complex assembly of four layers which can’t be directly linked to the classic succession of layers found in arthropods (e.g. endocuticle, exocuticle and epicuticle). These layers were named lamellar layer, parallel layer, soft helicoidal layer and highly mineralised layer. Each of them differs by fibres orientations, mineralisation rate or compositions and they are thought to play precise roles in the mechanical behaviour of the stomatopod spine. [less ▲]

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See detailMorphological differences between aerial and submerged sporidia of bio-fongicide Pseudozyma flocculosa CBS 16788
Zaki, Omran ULiege; Weekers, Frederic; Compère, Philippe ULiege et al

in PLoS ONE (2018)

Pseudozyma flocculosa is a fungus very useful and highly efficient as a biocontrol agent against powdery mildew. The reproduction of this fungus occurs exclusively by asexual production of conidia or ... [more ▼]

Pseudozyma flocculosa is a fungus very useful and highly efficient as a biocontrol agent against powdery mildew. The reproduction of this fungus occurs exclusively by asexual production of conidia or sporidia that are the most suitable form for agricultural use and seems to be the most resistant to storage conditions. Despite the advantages offered by P. flocculosa in biological control, the use of this fungus use remains largely limited compared to that of chemical fungicides, at least partly due to the difficulty to obtain sporidia resistant to adverse environmental stresses in submerged culture conditions. Under solid-state and submerged-state cultivation, P. flocculosa strain CBS 16788 produced different types of sporidia. The submerged sporidia (SS) appeared relatively uniform in size, which was 15, 4 ± 1,6 μm μm long, and 2,8 ± 0.8 μm wide. The aerial sporidia (AS) varied in shape and size, with a mean length of 8,2 ± 3 μm and width of 2,3 ± 0.6 μm. Under scanning and transmission electron microscopy, the cell wall of submerged sporidia was thinner than that of aerial spores, and the surface was smooth in contrast to the aerial sporidia that had a tendency to have verrucous, brittle surface characteristics. The thickness of the aerial sporidia wall is due to the presence of an outer layer rich in melanin. The sporidia germination was compared on YMPD (yeast extract, malt extract, soy peptone, dextrose and agar) coated coverslips. The aerial sporidia did not show germ tubes until 5 h of incubation, while the submerged sporidia showed many germ tubes after the same time. The resistance against the adverse environmental conditions in relation to the type of sporidia of P. flocculosa is discussed [less ▲]

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See detailStructures macroscopique et microscopique et formation des aegagropiles de Posidonia oceanica (L.) Delile (1813)
Lefebvre, Laurence ULiege; Gobert, Sylvie ULiege; Compère, Philippe ULiege et al

Poster (2018, April 11)

Il est courant de retrouver le long de plages de Méditerranée des agglomérations de débris végétaux originaire de l’herbier à Posidonies. Ces agglomérats portent le nom d’aegagropiles de P. oceanica ... [more ▼]

Il est courant de retrouver le long de plages de Méditerranée des agglomérations de débris végétaux originaire de l’herbier à Posidonies. Ces agglomérats portent le nom d’aegagropiles de P. oceanica , ceux-ci arborent des formes sphériques et ellipsoïdes. Les objectifs principaux de ce travail étaient d’identifier les différents composants des aegagropiles de P. oceanica et de déterminer la formation de ceux-ci. Pour ce faire, différentes analyses microscopiques (MET, MEB et MO) ont été effectuées ainsi que l’usage d’un mécanisme simulant la houle. Les observations en microscopie électronique à balayage ont été réalisées à l’aide de différents détecteurs (SSD et ETD) de SE et BSE, ce qui additionnés à diverses techniques de colorations et de contrastants ont permis de répondre à de nombreux objectifs. Les aegagropiles se forment par l’hydrodynamisme qu’engendre la houle et se composent d’un assemblage de débris végétaux provenant de P. oceanica ainsi que de grains de sable. Au fil des différentes étapes du cycle de la plante et de l’hydrodynamisme, les organes de la plante se rompent, s’accumulent au sein de la litière et subissent une combinaison de dégradations biotique et abiotique. Ces organes sont majoritairement des feuilles et des morceaux de rhizomes. La dégradation biotique est notamment engendrée par des champignons noirs septés nommés « Dark Septate Endophyte - DSE » qui, en s’attaquant spécifiquement à la lamelle mitoyenne des cellules permet des scissions longitudinales. La dégradation abiotique est quant à elle engendrée par les forces hydrodynamiques. Cette combinaison entraîne dès lors un lessivage important des différents organes végétaux qui se scindent et se courbent formant finalement de fines « fibres » qui s’accumuleront et s’entremêleront ensemble des ripples-marks afin d’élaborer des aegagropiles de P. oceanica. Les aegagropiles de P. oceanica se formeront initialement avec des débris intacts de rhizomes ou bien avec des faisceaux de fibres lignifiés ronds provenant également de ces rhizomes où de nombreux grains de nature minérale s’enchevêtreront à ces débris végétaux afin de constituer une structure initiale consolidée et résistante. Ensuite, d’autres débris végétaux, majoritairement de formes plates et provenant des feuilles et de gaines foliaires de P. oceanica , s’entremêleront à cette structure afin d’obtenir une agrégation allongée. Enfin, via une fragmentation aléatoire et des mouvements suivant préférentiellement une direction, des aegagropiles de P. oceanica de formes majoritairement ellipsoïdales s’échoueront le long des plages. [less ▲]

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See detailCidaroids spines facing ocean acidification
Dery, A.; Tran, P. D.; Compère, Philippe ULiege et al

in Marine Environmental Research (2018), 138

When facing seawater undersaturated towards calcium carbonates, spines of classical sea urchins (euechinoids) show traces of corrosion although they are covered by an epidermis. Cidaroids (a sister clade ... [more ▼]

When facing seawater undersaturated towards calcium carbonates, spines of classical sea urchins (euechinoids) show traces of corrosion although they are covered by an epidermis. Cidaroids (a sister clade of euechinoids) are provided with mature spines devoid of epidermis, which makes them, at first sight, more sensitive to dissolution when facing undersaturated seawater. A recent study showed that spines of a tropical cidaroid are resistant to dissolution due to the high density and the low magnesium concentration of the peculiar external spine layer, the cortex. The biofilm and epibionts covering the spines was also suggested to take part in the spine protection. Here, we investigate the protective role of these factors in different cidaroid species from a broad range of latitude, temperature and depth. The high density of the cortical layer and the cover of biofilm and epibionts were confirmed as key protection against dissolution. The low magnesium concentration of cidaroid spines compared to that of euechinoid ones makes them less soluble in general. © 2018 Elsevier Ltd [less ▲]

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See detailToward a continuous synthesis of porous carbon xerogel beads
Eskenazi, David; Kreit, Patrick ULiege; Pirard, Jean-Paul ULiege et al

in AIChE Journal (2018), 64

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See detailLiquid secretion and setal compliance: the beetle's winning combination for a robust and reversible adhesion
Gilet, Tristan ULiege; Heepe, Lars; Lambert, Pierre et al

in Current Opinion in Insect Science (2018), 30

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See detailEarly eukaryotes: insights from microanalyses of proterozoic microfossils
Cornet, Yohan ULiege; Beghin, Jérémie ULiege; Kabamba Baludikay, Blaise ULiege et al

in Goldschmidt Abstracts, 2017 (2017, August)

Detailed reference viewed: 40 (8 ULiège)