Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
Lateralization, i.e. the preferential use of one side of the body, may convey fitness benefits for organisms within rapidly-changing environments, by optimizing separate and parallel processing of different information between the two brain hemispheres. In coral reef-fishes, the movement of larvae from planktonic to reef environments (recruitment) represents a major life-history transition. This transition requires larvae to rapidly identify and respond to sensory cues to select a suitable habitat that facilitates survival and growth. This ‘recruitment’ is critical for population persistence and resilience. In aquarium experiments, larval Acanthurus triostegus preferentially used their right-eye to investigate a variety of visual stimuli. Despite this, when held in in situ cages with predators, those larvae that previously favored their left-eye exhibited higher survival. These results support the “brain’s right-hemisphere” theory, which predicts that the right-eye (i.e. left-hemisphere) is used to categorize stimuli while the left-eye (i.e. right-hemisphere) is used to inspect novel items and initiate rapid behavioral-responses. While these experiments confirm that being highly lateralized is ecologically advantageous, exposure to chlorpyrifos, a pesticide often inadvertently added to coral-reef waters, impaired visual-lateralization. This suggests that chemical pollutants could impair the brain function of larval fishes during a critical life-history transition, potentially impacting recruitment success.
ISSN: 2045-2322

Droits : http://creativecommons.org/licenses/by/
hal-01585550
http://hal.upmc.fr/hal-01585550
http://hal.upmc.fr/hal-01585550/document
http://hal.upmc.fr/hal-01585550/file/s41598-017-09381-0.pdf
DOI : 10.1038/s41598-017-09381-0

Éditeur(s) : Wiley-blackwell Publishing, Inc
Résumé : Vibrioses are the predominant bacterial infections in marine shrimp farms. Vibrio nigripulchritudo is an emerging pathogen of the cultured shrimp Litopenaeus stylirostris in New Caledonia and other regions in the Indo-Pacific. The molecular determinants of V. nigripulchritudo pathogenicity are unknown; however, molecular epidemiological studies have revealed that recent pathogenic V. nigripulchritudo isolates from New Caledonia all cluster into a monophyletic clade and contain a small plasmid, pB1067. Here, we report that a large plasmid, pA1066 (247 kb), can also serve as a marker for virulent V. nigripulchritudo, and that an ancestral version of this plasmid was likely acquired prior to other virulence-linked markers. Additionally, we demonstrate that pA1066 is critical for the full virulence of V. nigripulchritudo in several newly developed experimental models of infection. Plasmid pB1067 also contributes to virulence; only strains containing both plasmids induced the highest level of shrimp mortality. Thus, it appears that these plasmids, which are absent from non-pathogenic isolates, may be driving forces, as well as markers, for the emergence of a pathogenic lineage of V. nigripulchritudo.
Environmental Microbiology (1462-2912) (Wiley-blackwell Publishing, Inc), 2011-02 , Vol. 13 , N. 2 , P. 296-306

Droits : 2010 Society for Applied Microbiology and Blackwell Publishing Ltd
http://archimer.ifremer.fr/doc/00031/14196/11469.pdf
DOI:10.1111/j.1462-2920.2010.02329.x
http://archimer.ifremer.fr/doc/00031/14196/

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
Here we show that trying to rob prey (cleptobiosis) from a highly specialized predatory ant species is risky. To capture prey, Allomerus decemarticulatus workers build gallery-shaped traps on the stems of their associated myrmecophyte, Hirtella physophora. We wondered whether the frequent presence of immobilized prey on the trap attracted flying cleptoparasites. Nine social wasp species nest in the H. physophora foliage; of the six species studied, only Angiopolybia pallens rob prey from Allomerus colonies. For those H. physophora not sheltering wasps, we noted cleptobiosis by stingless bees (Trigona), social wasps (A. pallens and five Agelaia species), assassin bugs (Reduviidae), and flies. A relationship between the size of the robbers and their rate of capture by ambushing Allomerus workers was established for social wasps; small wasps were easily captured, while the largest never were. Reduviids, which are slow to extract their rostrum from prey, were always captured, while Trigona and flies often escaped. The balance sheet for the ants was positive vis-à-vis the reduviids and four out of the six social wasp species. For the latter, wasps began by cutting up parts of the prey's abdomen and were captured (or abandoned the prey) before the entire abdomen was retrieved so that the total weight of the captured wasps exceeded that of the prey abdomens. For A. pallens, we show that the number of individuals captured during attempts at cleptobiosis increases with the size of the Allomerus' prey.
ISSN: 0028-1042

hal-00825725
https://hal.archives-ouvertes.fr/hal-00825725
DOI : 10.1007/s00114-012-0895-3
PUBMED : 22361902

Éditeur(s) : Actes de colloques. Ifremer. Brest [ACTES COLLOQ. IFREMER.]. 1991
Résumé : On the bathyal slope for continental margins, steep and rocky substrates punctuated with cliffs and collapsing zones are frequently found. As survey and sampling with the classical technics from the sea surface is practically impossible in such an environment, in situ exploration with a submersible allows significant advances in ecology, with implications in paleoenvironment reconstruction. Mixing of material from shallow-water and deep-sea origins into bathyal sedimentation suggests that the so-called "fossil assemblages of outer platform" were frequently misinterpreted. Dense populations of animals closely related to fossil groups which were only considered as relict of the Past ("living fossils") and previously interpreted as shallow-water inhabitants during geological times can be discovered living in such bathyal communities. The role of bathyal ecological niches during global bioevents brings a new vision of the history of life in the Ocean through geological time and has to be further investigated. Examples from cruises monitoring the diving saucer Cyana (SP 3000) in the Bay of Biscay and off New Caledonia are given.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1990/acte-1138.pdf
http://archimer.ifremer.fr/doc/00000/1138/

Éditeur(s) : HAL CCSD
Résumé : International audience
Journal of Cystic Fibrosis
Dublin, Ireland

hal-01122611
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01122611
DOI : 10.1016/S1569-1993(12)60121-0

Éditeur(s) : HAL CCSD Elsevier Masson
Résumé : International audience
When fish larvae recruit back to a reef, chemical cues are often used to find suitable habitat or to find juvenile or adult conspecifics. We tested if the chemical information used by larvae was intentionally produced by juvenile and adult conspecifics already on the reef (communication process) or whether the cues used result from normal biochemical processes with no active involvement by conspecifics (“spying” behavior by larvae). Conspecific chemical cues attracted the majority of larvae (four out of the seven species tested); although while some species were equally attracted to cues from adults and juveniles (Chromis viridis, Apogon novemfasciatus), two exhibited greater sensitivity to adult cues (Pomacentrus pavo, Dascyllus aruanus). Our results indicate also that spying cues are those most commonly used by settling fishes (C. viridis, P. pavo, A. novemfasciatus). Only one species (D. aruanus) preferred the odour of conspecifics that had had visual contact with larvae (communication).
ISSN: 1631-0691

hal-01212899
https://hal-univ-perp.archives-ouvertes.fr/hal-01212899
DOI : 10.1016/j.crvi.2015.05.004

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Le groupe de recherche sur les avancées en pneumo-pédiatrie (GRAPP) a élaboré en 2013 des recommandations sur l'utilisation des nouveaux outils diagnostiques dans les infections respiratoires basses de l'enfant de plus de trois mois. Ces recommandations sont présentées ici en un texte court, le texte long est disponible sur le site de la Société française de pédiatrie www.sfpediatrie.com et de la Société pédiatrique de pneumologie et d'allergologie (SP2A) www.sp2a.fr.
ISSN: 0929-693X

hal-00994569
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00994569
DOI : 10.1016/j.arcped.2014.01.004
PUBMED : 24613479

Éditeur(s) : HAL CCSD American Geophysical Union
Résumé : International audience
The Main Himalayan Thrust (MHT) is the source of great earthquakes that have been documented along the range. Its geometry is a key parameter that influences accommodation of tectonic loading and earthquake magnitudes along the Himalayan Arc. Although seismic images are available for both the western and the central part of the range, this geometry remains poorly constrained for the Bhutanese Himalayas. Here we address this issue using a 10Be cosmogenic nuclides denudation transect across western Bhutan. We observe a wide low denudation rate domain between 50 km and 110 km from the front followed by a strong northward increase. Using a joint inversion of denudation rates, GPS data, and Holocene uplift rates, we interpret this pattern as a consequence of a flat-ramp transition along the MHT. Compared to central Nepal and Sikkim, this location of the ramp suggests a wider décollement, with implications for greater seismogenic potential of the MHT in western Bhutan.
ISSN: 0094-8276

Droits : info:eu-repo/semantics/OpenAccess
hal-01174088
https://hal.archives-ouvertes.fr/hal-01174088
https://hal.archives-ouvertes.fr/hal-01174088v2/document
https://hal.archives-ouvertes.fr/hal-01174088/file/lerouxmalloufGRL2015.pdf
DOI : 10.1002/2015GL063767