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Aquaculture is one of the most prosperous economic sectors. Nevertheless, the natural outbreaks of several infectious diseases make the sector to deal with important economic losses. One of the most important pathogens in the Mediterranean Sea is nodavirus (NNV). NNV is the agent causing viral encephalopathy and retinopathy in more than 170 fish species including some of the most impact in Spanish hatcheries as European sea bass (Dicentrarchus labrax). Antimicrobial peptides (AMPs) are short aminoacidic sequences which constitute important mediators of the innate immune response in teleost fish. AMPs can kill directly a broad range of pathogens such as bacteria or viruses and modulate the host immune response leading to a more effective clearance of pathogens. These properties along with the world emergency in antimicrobial resistance (AMR) make AMPs good candidates to replace traditional antimicrobials. Therefore, we aimed to analyze the molecular regulation of European sea bass defensin beta genes upon NNV infection and after NNV vaccination. To achieve our objective, European sea bass were infected with NNV and samples of head-kidney (HK), brain and gonad were taken. In addition, gonadal cells from healthy males were in vitro stimulated with NNV. Then, ovary samples of control females or vaccinated against NNV (pBAD vaccine) were taken, as well as fertilized eggs and larvae from the same groups. To support our data, we also analyzed in silico the potential antiviral activity of the protein encoded by the studied genes. Our results show that defensin beta 1 gene is up-regulated upon in vivo NNV infection even if in the in silico study showed the lesser predicted activity. Interestingly, the in vitro NNV challenge resulted in no variation of the defensin beta 1 gene, while defensin beta 2.1 and 2.2 genes were blocked upon this stimulus. Strikingly, females vaccinated with pBAD greatly down-regulate defensin beta 2.2 expression. Moreover, larvae from vaccinated mother up-regulate all defensin beta genes. In conclusion, defensin beta 1 gene seems to be involved in the defense against viruses while defensin beta 2 genes appear to possess a more specific function in gonad. Evaluación de los efectos de las microalgas, incluidas en dietas de dorada, sobre el crecimiento, supervivencia y resistencia a infecciones. ALGAFISH

International audience; This preliminary study explored the capture potential of the Marquesan Islands for fish larvae, especially endemic species, with the set up of light traps on either offshore site or coastal site between January and March 2012. Among the 323 fish larvae belonging to 29 captured species, 151 fish larvae belonging to five species were endemic. Light traps captured more endemic larvae in coastal site than in offshore sites. Overall, this study allows to better understand larval supply of endemic fish species in an isolated region such as the Marquesan Islands.

The present study aims to evaluate differences in the incorporation efficiency and the possible interactions among highly unsaturated fatty acids (HUFA) during enrichment and starvation of Artemia nauplii. Artemia franciscana nauplii were enriched with emulsions containing docosahexaenoic acid (DHA, 22:6n-3), eicosapentaenoic acid (EPA, 20:5n-3) or arachidonic acid (AA, 20:4n-6) as sole HUFA or with different ratios of these HUFA during 24 h at 28°C and subsequently starved for 24 h at the same temperature. The comparison of HUFA incorporation efficiency when supplying the three HUFA separately showed a less efficient enrichment of DHA as compared to AA or EPA. DHA incorporation was always accompanied by an EPA increase, indicating the metabolic conversion of DHA to EPA by the nauplii during the enrichment process. When offering the HUFA together, we found no competitive interaction of EPA or of AA on DHA incorporation. Only in the case of the 97% (% total fatty acids) n-3 HUFA emulsion, some negative interference might have occurred between the HUFA, as it gave a lower incorporation of 22:6n-3 and 20:5n-3 than the emulsions with lower n-3 HUFA content. During the subsequent starvation of EPA- or DHA-enriched Artemia, relative EPA and DHA losses were similarly high in both treatments. In contrast, the presence of DHA in naupliar lipids increased the EPA retention, which might however be related to DHA retroconversion.

Evaluer, maintenir et restaurer les conditions écologiques des rivières nécessitent des mesures du fonctionnement de leurs écosystèmes. De par leur complexité, notre compréhension de ces systèmes est imparfaite. La prise en compte des incertitudes et variabilités liées à leur évaluation est donc indispensable à la prise de décision des gestionnaires. En analysant des données nationales (~ 1654 sites), les objectifs principaux de cette thèse étaient de (1) tester certaines hypothèses intrinsèques aux bio-indicateurs et (2) d'étudier les incertitudes de l'évaluation écologique associées à la variabilité temporelle des bio-indicateurs et à la prédiction des conditions de référence. (1) Ce travail met en évidence (i) le rôle prépondérant des facteurs environnementaux naturels dans la structuration des communautés aquatiques en comparaison des facteurs anthropiques (définis à l'échelle du bassin versant, du corridor riparien et du tronçon), (ii) les réponses contrastées des communautés aquatiques aux pressions humaines (dégradations hydro-morphologiques et de la qualité de l'eau) et (iii) plus généralement, les forts impacts des barrages et de l'altération de la qualité de l'eau sur les communautés aquatiques. (2) Une méthode Bayésienne a été développée pour estimer les incertitudes liées à la prédiction des conditions de référence d'un indice piscicole (IPR+). Les incertitudes prédictives de l'IPR+ dépendent du site considéré mais aucune tendance claire n'a été observée. Par comparaison, la variabilité temporelle de l'IPR+ est plus faible et semble augmenter avec l'intensité des perturbations anthropiques. Les résultats de ce travail confirment l'avantage d'indices multi-métriques basés sur des traits fonctionnels par rapport à ceux relatifs à la composition taxonomique. Les sensibilités différentes des macrophytes, poissons, diatomées et macro-invertébrés aux pressions humaines soulignent leur complémentarité pour l'évaluation des écosystèmes fluviaux. Néanmoins, de futures recherches sont nécessaires à une meilleure compréhension des effets d'interactions entre types de pressions et entre pressions humaines et environnement. Sensitive biological measures of ecosystem quality are needed to assess, maintain or restore the ecological conditions of rivers. Since our understanding of these complex systems is imperfect, river management requires recognizing variability and uncertainty of bio-assessment for decision-making. Based on the analysis of national data sets (~ 1654 sites), the main goals of this work were (1) to test some of the assumptions that shape bio-indicators and (2) address the temporal variability and the uncertainty associated to prediction of reference conditions.(1) This thesis highlights (i) the predominant role of physiographic factors in shaping biological communities in comparison to human pressures (defined at catchment, riparian corridor and reach scales), (ii) the differences in the responses of biological indicators to the different types of human pressures (water quality, hydrological, morphological degradations) and (iii) more generally, the greatest biological impacts of water quality alterations and impoundments. (2) A Bayesian method was developed to estimate the uncertainty associated with reference condition predictions of a fish-based bio-indicator (IPR+). IPR+ predictive uncertainty was site-dependent but showed no clear trend related to the environmental gradient. By comparison, IPR+ temporal variability was lower and sensitive to an increase of human pressure intensity. This work confirmed the advantages of multi-metric indexes based on functional metrics in comparison to compositional metrics. The different sensitivities of macrophytes, fish, diatoms and macroinvertebrates to human pressures emphasize their complementarity in assessing river ecosystems. Nevertheless, future research is needed to better understand the effects of interactions between pressures and between pressures and the environment.

International audience; Eurofl eets is a key research infrastructure, essential for collecting in situ marine data sets from global oceans, regional seas and coastal waters. Research vessels carry and operate shipborne observation equipment and facilitate deployment and handling of a large range of observing and sampling instruments. The infrastructure is also evolving, with fixed ocean seafl oor observation and mobile surface and subsea autonomous technologies presenting challenges to the existing fl eet to deploy and maintain. Meeting the complex end user needs of European scientists across disciplines and geographic locations is an expensive and complex exercise requiring coordination at national and international levels, and the use of common standards and approaches. To meet the expected challenges, Eurofl eets+ (An alliance of European marine research infrastructure to meet the evolving needs of the research and industrial communities) project is undertaking Joint Research Activities (JRA) with key industry partners. Specifi cally, the objective of JRA 3.2 led by CSIC, with the Marine Institute and industry partners Hampidjan, MacArtney AS and SEAONICS is the study and conceptual development of equipment for deep sea operations from research vessels co-designed by research and industry partners.Improving interoperability of Large Exchangeable Instrumentation (LEXI) is a primary aim of Eurofl eets+, especially in terms of improvement and standardisation of tools/rigging for more effi cient operations.The collaborative approach aims to develop a new deep-sea winch design, a multipurpose crane/handling system for deep water operations and a dual mode handling system designed for the deployment and recovery of research tools through moon-pools or/and over the side.

Higher cognition may require the globally coordinated integration of specialized brain regions into functional networks. A collection of structural cortical hubs—referred to as the rich club—has been hypothesized to support task-specific functional integration. In the present paper, we use a whole-cortex model to estimate directed interactions between 68 cortical regions from functional magnetic resonance imaging activity for four different tasks (reflecting different cognitive domains) and resting state. We analyze the state-dependent input and output effective connectivity (EC) of the structural rich club and relate these to whole-cortex dynamics and network reconfigurations. We find that the cortical rich club exhibits an increase in outgoing EC during task performance as compared with rest while incoming connectivity remains constant. Increased outgoing connectivity targets a sparse set of peripheral regions with specific regions strongly overlapping between tasks. At the same time, community detection analyses reveal massive reorganizations of interactions among peripheral regions, including those serving as target of increased rich club output. This suggests that while peripheral regions may play a role in several tasks, their concrete interplay might nonetheless be task-specific. Furthermore, we observe that whole-cortex dynamics are faster during task as compared with rest. The decoupling effects usually accompanying faster dynamics appear to be counteracted by the increased rich club outgoing EC. Together our findings speak to a gating mechanism of the rich club that supports fast-paced information exchange among relevant peripheral regions in a task-specific and goal-directed fashion, while constantly listening to the whole network. DATA_TASK_3DMOV_HP_CSF_WDBriefly, data comes from five functional runs consisting of a resting-state measurement (eyes closed), four individual task measurements including a visual n-back (n=2) task (Kirchner, 1958), the Eriksen flanker task (Eriksen & Eriksen, 1974), a mental rotation task (Shepard & Metzler, 1971), and a verbal odd-man-out task (Flowers & Robertson, 1985). All runs comprise 192 data points with tasks being continuously performed during this period. For the n-back and flanker task, stimuli were presented at a rate of 0.5 Hz; for the mental rotation and odd-man out tasks they were presented at a rate of 0.25 Hz. Task sequence was counterbalanced across participants with the exception that the resting state functional run was always acquired first to prevent carry-over effects (Grigg & Grady, 2010). The data were acquired using a 3 Tesla Siemens Prisma Fit (upgraded Tim Trio) scanner and a 64-channel head coil. Initial preprocessing was performed using BrainVoyager QX (v2.6; Brain Innovation, Maastricht, the Netherlands). This includes slice scan time correction, 3D-motion correction, high-pass filtering with a frequency cutoff of .01 Hz, and registration of functional and anatomical images. Subsequently, using MATLAB (2013a, The MathWorks,Natick, MA), signals were cleaned by performing wavelet despiking (Patel & Bullmore, 2015) and regressing out a global noise signal given by the first principal component of signals observed within the cerebrospinal fluid of the ventricles. Next, voxels were uniquely assigned to one of the 68 cortical ROIs specified by the DK atlas and an average BOLD time-series was computed for each region as the mean time-series over all voxels of that region.

A 53-year-old man with a recent history of left temporal lobe hemorrhage presented with weakness of left upper limb for 4 days. Paragonimus eggs were detected in patient's sputum. Work up revealed paragonimiasis, a lung fluke worm infection endemic to East Africa, West Africa and South America which rarely involves in brain. Characteristic tunnel sign was visualized on brain MRI. Notably, susceptibility-weighted imaging revealed a migratory pattern of the parasite from the left temporal lobe to the right parietal lobe and resultant patchy hemorrhage. Treatment with praziquantel resulted in favorable outcome without residual deficits.

In most animals, the brain makes behavioral decisions that are transmitted by descending neurons to the nerve cord circuitry that produces behaviors. In insects, only a few descending neurons have been associated with specific behaviors. To explore how descending neurons control an insect's movements, we developed a novel method to systematically assay the behavioral effects of activating individual neurons on freely behaving terrestrial D. melanogaster. We calculated a two-dimensional representation of the entire behavior space explored by these flies and we associated descending neurons with specific behaviors by identifying regions of this space that were visited with increased frequency during optogenetic activation. Applying this approach across a large collection of descending neurons, we found that (1) activation of most of the descending neurons drove stereotyped behaviors, (2) in many cases multiple descending neurons activated similar behaviors, and (3) optogenetically-activated behaviors were often dependent on the behavioral state prior to activation. Movies of optogenetically activated split-Gal4 linesEach movie contains 1 second before and after optogenetic stimulation for all experimental (retinal +) and control (retinal -) flies for all stimulation trials.opto_movies.zip

Attending to a task-relevant location changes how neural activity oscillates in the alpha band (8–13Hz) in posterior visual cortical areas. However, a clear understanding of the relationships between top-down attention, changes in alpha oscillations in visual cortex, and attention performance are still poorly understood. Here, we tested the degree to which the posterior alpha power tracked the locus of attention, the distribution of attention, and how well the topography of alpha could predict the locus of attention. We recorded magnetoencephalographic (MEG) data while subjects performed an attention demanding visual discrimination task that dissociated the direction of attention from the direction of a saccade to indicate choice. On some trials, an endogenous cue predicted the target’s location, while on others it contained no spatial information. When the target’s location was cued, alpha power decreased in sensors over occipital cortex contralateral to the attended visual field. When the cue did not predict the target’s location, alpha power again decreased in sensors over occipital cortex, but bilaterally, and increased in sensors over frontal cortex. Thus, the distribution and the topography of alpha reliably indicated the locus of covert attention. Together, these results suggest that alpha synchronization reflects changes in the excitability of populations of neurons whose receptive fields match the locus of attention. This is consistent with the hypothesis that alpha oscillations reflect the neural mechanisms by which top-down control of attention biases information processing and modulate the activity of neurons in visual cortex. IkkaiDataUpload

Ocean acidification is perceived to be a major threat for many calcifying organisms, including scleractinian corals. Here we investigate (1) whether past exposure to low pH environments associated with CO2 vents could increase corals tolerance to low pH and (2) whether zooxanthellate corals are more tolerant to low pH than azooxanthellate corals. To test these hypotheses, two Mediterranean colonial corals Cladocora caespitosa (zooxanthellate) and Astroides calycularis (azooxanthellate) were collected from CO2 vents and reference sites and incubated in the laboratory under present-day (pH on the total scale, pHT 8.07) and low pH conditions (pHT 7.70). Rates of net calcification, dark respiration and photosynthesis were monitored during a six-month experiment. Monthly net calcification was assessed every 27 to 35 d using the buoyant weight technique, whereas light and dark net calcification was estimated using the alkalinity anomaly technique during 1 h incubations. Neither species showed any change in net calcification rates, respiration, and photosynthesis regardless of their environmental history, pH treatment and trophic strategy. Our results indicate that C. caespitosa and A. calycularis could tolerate future ocean acidification conditions for at least 6 months. These results will aid in predicting species' future responses to ocean acidification, and thus improve the management and conservation of Mediterranean corals. In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2021) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2022-04-11.