Etude ultrastructurale du spermatozoïde de Deropristis inflata, molin 1958, (Digenea, Acanthocolpidae), parasite de l’anguille, Anguilla anguilla, Linnaeus, 1758

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Characterization of aerosols emissions from the combustion of dead shrub twigs and leaves using a cone calorimeter

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Parasites communities in brown trout Salmo trutta (Pisces, Teleostei) from corsican rivers

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Etude de la parasitofaune des poissons d’eau douce de corse : II. Les espèces diadromes (thalassotoque et potamotoque) : l’anguille d’europe (Anguilla anguilla) et l’alose feinte (Alosa fallax)

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Etude de la parasitofaune des poissons d’eau douce de Corse : I. Les espèces dulçaquicoles : les Salmonidés

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In Vivo Characterization of Neurophysiological Diversity in the Lateral Supramammillary Nucleus during Hippocampal Sharp-wave Ripples of Adult Rats

International audienceThe extent of the networks that control the genesis and modulation of hippocampal sharp-wave ripples (SPW-Rs), which are involved in memory consolidation, remains incompletely understood. Here, we performed a detailed in vivo analysis of single cell firing in the lateral supramammillary nucleus (lSuM) during theta and slow oscillations, including SPW-Rs, in anesthetized rats. We classified neurons as SPW-R-active and SPW-R unchanged according to whether or not they increased their firing during SPW-Rs. We show that lSuM SPW-R active neurons increase their firing prior to SPW-Rs peak power and prior to hippocampal excitatory cell activation. Moreover, lSuM SPW-R-active neurons show increased firing activity during theta and slow oscillations as compared to unchanged neurons. These results suggest that a sub-population of lSuM neurons can interact with the hippocampus during SPW-Rs, raising the possibility that the lSuM may modulate memory consolidation

Characterization of aerosols emissions from the combustion of dead shrub twigs and leaves using a cone calorimeter

WOS:000407982400091International audienceThis work is a contribution to the understanding of wildfire smoke emissions. It focuses on the characterization of aerosols emitted by the combustion of dead shrub leaves and twigs with different thickness (range of 0.75-20 mm). The experiments were carried out at bench scale with a cone calorimeter for the burning of Cistus monspeliensis leaves and twigs. Auto-igthtion of the samples was obtained by heating their surface with a radiant heat flux of 50 kW/m(2). The smoke and aerosols emitted before ignition during pre-heating were analysed separately from the smoke and aerosols emitted during the flaming phase. Heat release rate (HRR) was also measured and we observed two different behaviours depending on the diameter of the twigs. Fuel samples with diameter smaller than 4 mm exhibit a single peak HRR whereas two peaks were observed for the twigs with larger diameters. The smoke production rate (SPR) was also measured and it showed that smoke was mainly emitted during the pre-heating phase. We also obtained a strong correlation between HRR and SPR during the flaming phase but no smoke was emitted, during the glowing phase. Emission factors of aerosols were calculated depending on these combustion phases (pre-ignition and flaming) and for the range of thickness of the samples. The observations of the aerosols were performed by scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The chemical composition of organic carbon (OC) aerosols, emitted during the pre-ignition phase, were analysed using gas chromatography (GC) coupled with mass spectrometry (MS). Some carcinogenic compounds were identified. The sizes of OC and black carbon (BC) aerosols emitted were measured with an optical device. Most of the BC were PM0.3, which corresponds to the alveolar fraction of particles

Corbu, I Pianoli, Bocca di Cavu : Corse, Corse-du-Sud (2A), Sartène: Rapport de diagnostic

Ce diagnostic a permis de détecter de rares vestiges d'un site protohistorique de chronologie indéterminée, constitués de deux fosses presque totalement érodées. Un abri sous roche situé sous un chaos granitique a fait l'objet d'une fouille exhaustive. Le mobilier a permis de caractériser une utilisation de la cavité à l'époque sub-contemporaine (phase pendant laquelle l'abri est fermé sur ses deux côtés), succédant à une occupation mal caractérisée, attribuable à la fin du Ier millénaire avant J.-C. Si un charbon de bois daté du Bronze récent provient du remplissage d'une longue fosse, il n'a pas été possible d'observer de traces d'activité dans l'abri au cours du IIe millénaire. En revanche, la partie inférieure de la stratigraphie a livré une série de céramique et lithique de type basien, qui peut être datée du IVe millénaire. L'opération a, en outre, permis de réaliser une étude de murs en pierre sèche non cadastrés et de fouiller une aire de battage. Il semblerait que ce soit la première fois que ce type d'enquête est mené sur une aghja, structure typique des paysages agricoles insulaires à l'époque moderne. Ces travaux ont révélé la structure de l'édifice ainsi que des aménagements de préparation du terrain préalables à la construction. Après l'abandon, une fosse est creusée au centre du dispositif, dans un but indéterminé, avant d'être emplie de blocs

Disordered information processing dynamics in experimental epilepsy

Neurological disorders share common high-level alterations, such as cognitive deficits, anxiety, and depression. This raises the possibility of fundamental alterations in the way information conveyed by neural firing is maintained and dispatched in the diseased brain. Using experimental epilepsy as a model of neurological disorder we tested the hypothesis of altered information processing, analyzing how neurons in the hippocampus and the entorhinal cortex store and exchange information during slow and theta oscillations. We equate the storage and sharing of information to low level, or primitive, information processing at the algorithmic level, the theoretical intermediate level between structure and function. We find that these low-level processes are organized into substates during brain states marked by theta and slow oscillations. Their internal composition and organization through time are disrupted in epilepsy, loosing brain state-specificity, and shifting towards a regime of disorder in a brain region dependent manner. We propose that the alteration of information processing at an algorithmic level may be a mechanism behind the emergent and widespread co-morbidities associated with epilepsy, and perhaps other disorders

The Nucleus Reuniens Controls Long-Range Hippocampo–Prefrontal Gamma Synchronization during Slow Oscillations

International audienceGamma oscillations are involved in long-range coupling of distant regions that support various cognitive operations. Here we show in adult male rats that synchronized bursts of gamma oscillations bind the hippocampus (HPC) and prefrontal cortex (mPFC) during slow oscillations and slow-wave sleep, a brain state that is central for consolidation of memory traces. These gamma bursts entrained the firing of the local HPC and mPFC neuronal populations. Neurons of the nucleus reuniens (NR), which is a structural and functional hub between HPC and mPFC, demonstrated a specific increase in their firing before gamma burst onset, suggesting their involvement in HPC-mPFC binding. Chemical inactivation of NR disrupted the temporal pattern of gamma bursts and their synchronization, as well as mPFC neuronal firing. We propose that the NR drives long-range hippocampo-prefrontal coupling via gamma bursts providing temporal windows for information exchange between the HPC and mPFC during slow-wave sleep. Significance Statement Long-range coupling between hippocampus (HPC) and prefrontal cortex (mPFC) is believed to support numerous cognitive functions, including memory consolidation occurring during sleep. Gamma-band synchronization is a fundamental process in many neuronal operations and is instrumental in long-range coupling. Recent evidence highlights the role of nucleus reuniens (NR) in consolidation; however, how it influences hippocampo-prefrontal coupling is unknown. In this study, we show that HPC and mPFC are synchronized by gamma bursts during slow oscillations in anesthesia and natural sleep. By manipulating and recording the NR-HPC-mPFC network, we provide evidence that theNRactively promotes this long-range gamma coupling. This coupling provides the hippocampo-prefrontal circuit with a novel mechanism to exchange information during slow-wave sleep