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Area CA2 is a critical region for diverse hippocampal functions including social recognition memory. This region has unique properties and connectivity. Notably, intra-hippocampal excitatory inputs to CA2 lack canonical long-term plasticity, but inhibitory transmission expresses a long-term depression mediated by Delta-opioid receptors (DOR-iLTDs). Evidence indicates that DOR-iLTDs are insufficient to underlie social coding. Here, we report a novel inhibitory plasticity mediated by cannabinoid type 1 receptor activation (CB1R-iLTD). Surprisingly, CB1R-iLTD requires previous induction of DOR-iLTDs, indicating a permissive role for DOR plasticity. Blockade of CB1Rs in CA2 completely prevents social memory formation. Furthermore, the sequentiality of DOR- and CB1R-mediated plasticity occurs in vivo during successive social interactions. Finally, CB1R-iLTD is altered in a mouse model of schizophrenia with impaired social cognition but is rescued by a manipulation that also rescues social memory. Altogether, our data reveal a unique interplay between two inhibitory plasticities and a novel mechanism for social memory formation.

International audience; Parvalbumin (PV)-expressing interneurons which are often associated with the specific extracellular matrix perineuronal net (PNN) play a critical role in the alteration of brain activity and memory performance in Alzheimer's disease (AD). The integrity of these neurons is crucial for normal functioning of the hippocampal subfield CA2, and hence, social memory formation. Here, we find that social memory deficits of mouse models of AD are associated with decreased presence of PNN around PV cells and long-term synaptic plasticity in area CA2. Furthermore, single local injection of the growth factor neuregulin-1 (NRG1) is sufficient to restore both PV/PNN levels and social memory performance of these mice. Thus, the PV/PNN disruption in area CA2 could play a causal role in social memory deficits of AD mice, and activating PV cell pro-maturation pathways may be sufficient to restore social memory.

[EN] Rabbit haemorrhagic disease (RHD) is a critical health threat to the rabbit industry in Europe. In 2018, the French rabbit industry adopted a voluntary control plan against this disease. In this context, two epidemiological studies were conducted on RHD outbreaks that occurred between 2013 and 2018 in France. The objectives were to describe the spread of RHD due to the new genotype RHDV GI.2 (rabbit haemorrhagic disease virus GI.2) and to identify rearing factors influencing the occurrence of the disease in order to guide the prevention measures recommended in the control plan. An analysis of cases on 295 farms between 2013 and 2017 showed that 32% of farms were affected at least once; the incidence of the disease increased in 2016-2017 compared to 2013-2015. Farms already affected in 2013-2015 had a higher risk of being infected in 2016-2017 than those that remained unaffected until 2015 (Relative Risk and 95% Confident Interval 1.7 [1.1-2.7]). A case-control study carried out between 2016 and 2018 on 37 outbreaks and 32 control farms revealed variability in biosecurity and decontamination practices between farms. The risk of being infected tends to be linked to these practices, but certain structural factors (e.g. the manure disposal system, transfer of rabbits at weaning) could also influence the risk of virus introduction into farms. In the context of a limited vaccination coverage of the farms (only females are vaccinated), these hypotheses will be studied further, using information from the RHD outbreak monitoring system implemented at the same time as the control plan in 2018., This study was founded by the French Ministry of Agriculture (2017-430 / 170274).

Able to monitor very precisely CO2 gases concentration in the atmosphere (better than 1 ppm), MicroCarb is a CNES mission which instrument is a passive Short Wave InfraRed spectrometer that will help scientists to better understand the planet’s major ecosystems and gain a clearer picture of its carbon budget at regional scales. Reaching such a monitoring precision means that the instrument has very stringent requirements especially in terms of radiometry, spectral filtering, spectral bands co-registration and polarization sensitivity. The MicroCarb instrument is currently under integration at Airbus Defence and Space facilities in Toulouse (France). It is based on an innovative concept permitting the acquisition of the spectral bands using a single split-pupil telescope, spectrometer and detector. Spectral bands multiplexing is obtained by the grating, each band corresponding to a different diffraction order, between 15 and 40. The split-pupil concept is characterized by 3 sets of 4 to 5 assembled prisms at entrance telescope pupil, spectrometer slit and in front of the detector, all participating to the complex spectral filtering. All the components considered as critical for the performances of the instrument have been manufactured and are under integration: the echelle grating replicated in a SiC substrate, the assembled optical elements with narrow spectral filtering coatings and the Dual Babinet polarization scrambler. In this paper we will focus on these optical components, detailing for each one how the stringent requirements of the instrument have been transposed to their specification, close to the limits of manufacturability. We will be able to present their development and achievement with respect to these specifications and how they impact the global performances of the instrument.

Group III metabotropic glutamate (mGlu) receptors modulate glutamatergic and GABAergic transmission in the basal ganglia. In this study, we examined a novel orthosteric agonist at the mGlu4 receptor, LSP1-2111, for its ability to affect L-DOPA-induced dyskinesia (LID), in a mouse model. In 6-OHDA-lesioned mice treated with L-DOPA, chronic co- administration of LSP1-2111 significantly attenuated the development of abnormal involuntary movements, which are regarded as a marker of dyskinesia. In contrast, a single injection of LSP1-2111 did not modify the expression of LID, once this condition had been established by previous administration of L-DOPA. LSP1-2111 did not affect L-DOPA-induced cAMP and extracellular signal-regulated protein kinase signaling, which have been previoulsy implicated in dyskinesia. These results indicate that co-administration of LSP1-2111 may improve the efficacy of standard L-DOPA therapy by attenuating its liability for dyskinesia.

International audience; Stereoisomers of 1-amino-2-phosphonomethylcyclopropanecarboxylic acid (APCPr), conformationally restricted analogues of L-AP4 (2-amino-4-phosphonobutyric acid), have been prepared and evaluated at recombinant group III metabotropic glutamate receptors. They activate these receptors over a broad range of potencies. The most potent isomer (1S,2R)-APCPr displays a similar pharmacological profile as that of L-AP4 (EC50 0.72, 1.95, >500, 0.34 microM at mGlu4, 6, 7, 8 receptors, respectively, and no effect at group I/II mGluRs). It was characterized on native receptors located in the basal ganglia (BG) where it induced a robust and reversible inhibition of synaptic transmission. It was tested in vivo in haloperidol-induced catalepsy, a model of Parkinsonian akinesia, by direct infusion in the globus pallidus of the BG. At a dose of 0.5 nmol/microL, catalepsy was significantly antagonized. This study reveals that (1S,2R)-APCPr is a potent group III mGluR agonist and confirms that these receptors may be considered as a therapeutic target in the Parkinson's disease.

Cadmium is very toxic at low concentrations, but the basis for its toxicity is not clearly understood. We analyzed the proteomic response of yeast cells to acute cadmium stress and identified 54 induced and 43 repressed proteins. A striking result is the strong induction of 9 enzymes of the sulfur amino acid biosynthetic pathway. Accordingly, we observed that glutathione synthesis is strongly increased in response to cadmium treatment. Several proteins with antioxidant properties were also induced. The induction of nine proteins is dependent upon the transactivator Yap1p, consistent with the cadmium hypersensitive phenotype of the YAP1-disrupted strain. Most of these proteins are also overexpressed in a strain overexpressing Yap1p, a result that correlates with the cadmium hyper-resistant phenotype of this strain. Two of these Yap1p-dependent proteins, thioredoxin and thioredoxin reductase, play an important role in cadmium tolerance because strains lacking the corresponding genes are hypersensitive to this metal. Altogether, our data indicate that the two cellular thiol redox systems, glutathione and thioredoxin, are essential for cellular defense against cadmium.

The adhesion between metals and polymers has attracted much interest in recent years due to the increasing use of metal/polymer assemblies, for example, in the fields of packaging, architecture, and automotive manufacturing. Among the parameters controlling the adhesion properties of metal/polymer systems, the acid-base properties of both materials appear to play an important role. Two methods are proposed for assessing and quantifying the acido-basicity of passive films on metals: X-ray photoelectron spectroscopy (XPS and X-ray absorption near edge structure (XANES). These techniques were used here to characterize the acid-base properties of a large set of passivated aluminum surfaces. Both XPS-monitored Fermi level shift and XANES formic acid and pyridine adsorption measurements were found in good agreement in the establishment of a relative basicity scale for the studied surfaces. Moreover, the results were cross-va idate with those of the novel photoelectrochemical approach to the acid-base properties of aluminum surfaces presented in Part I.

The acid-base properties of aluminum surfaces have recently attracted much interest due to their consequences on the adhesion of organic coatings. The present work deals with a novel photoelectrochemical approach to the acid-base properties of aluminum surfaces. Passive films were considered here as wide-gap semiconductors. When they are in contact with an electrolyte, a space charge builds up. A negative (positive) space charge is considered here as a sign of an electron donor (acceptor) surface, i.e., to a Lewis basic (acid) surface. The more negative (positive) the space charge or the corresponding band bending in the semiconductor, the more basic (acid) the passivated surface. The spectrophotoelectrochemical response of the samples polarized at the rest potential under ultraviolet illumination allowed the measurement of the band bending as the difference between the thresholds of two photoemission phenomena from the Fermi level toward the passive film conduction band at the inner and outer interfaces of the passive films. Negative band bendings were always obtained, evidencing the basic character of the analyzed surfaces. A basicity scale was obtained which is compared in Part II to that deduced from X-ray photoelectron and X-ray absorption near-edge structure studies.

The existence of β-C 3 N 4 with hardness characteristics similar or better than diamond was predicted in 1990 by Liu and Cohen. Many studies have since been devoted to the synthesis of this compound. In the present work, carbon nitride films were deposited by various reactive magnetron sputtering processes of graphite targets in pure nitrogen and characterized by AES, XPS, x-ray adsorption near-edge structure (XANES) and static time-of-flight SIMS (ToF-SIMS). Various bonding states (single and double bond) are observed between carbon and nitrogen atoms and between carbon atoms but there is no evidence in the XANES results for either the presence of carbon-nitrogen triple bonds or a pyridine-like ring structure. Surface N/C ratios were estimated to be close to 0.3. Carbon K-edge XANES lineshapes, the C 1s plasmon-loss structure and the calculated density (2.2 g cm -3 ) indicate that the films are similar to diamond-like carbon without long-range ordering. The presence of C x N y fragments with 1 ≤ y < 4 and the low abundance of CH x and CH x N y fragments in ToF-SIMS spectra further confirm that the carbon atoms do not adopt a graphite or pyridine-like cyclic two-dimensional structure and that the films are not significantly hydrogenated. A three-phase solid solution model is proposed for the composition of the films: a 'free' carbon phase, an sp 3 -carbon-nitrided phase and an sp 2 -carbon-nitrided phase. The relative proportion of these phases is influenced by the deposition conditions. Enhanced plasma ionization reactive magnetron sputtering leads to higher density and to a higher fraction of the sp 3 carbon phase.

RATIONALE: Metabotropic glutamate mGlu receptors 5 (mGluR5) receptors are abundant in corticolimbic circuitry where they modulate glutamate and dopamine signal transduction. OBJECTIVES: In this study, we explored the hypothesis that mGluR5 antagonist, (2-methyl-6-(phenylethynyl)pyridine hydrochloride) (MPEP), facilitates dopamine-dependent effects on memory and motor functions. METHODS: To this aim, we examined the effects of different doses (from 0 to 24 mg/kg) of the mGluR5 antagonist, MPEP, on the modulation of amphetamine-dependent behaviors, namely passive avoidance, locomotor activity, and rotation behavior in intact and dopamine-depleted CD1 male mice. RESULTS: We demonstrated that a low dose (3 mg/kg) of MPEP, which is void of behavioral effects on its own, facilitates amphetamine-induced effects independently on the behavior measured both in naïve and in dopamine-lesioned mice; this synergistic effect is lost when higher doses of MPEP are used. CONCLUSION: The results are discussed in terms of possible balance between dopamine and glutamate activity in regulating the proper fine tuning of information processing.

Hard coatings are commonly used today to enhance the life of numerous tools and wear parts. As carbon nitride and TiN/NbN superlattice films prepared by reactive sputtering were being evaluated for such tribological applications, it appeared necessary to test their thermal behavior to determine their stability at high temperatures. The coatings were reactively sputtered on silicon, M1 steel, or cemented carbide substrates. Two deposition conditions were used for the carbon nitride films producing either soft or hard films. The effect of a metal interlayer, either chromium or titanium, has also been studied. Two modulation periods were used for the TiN/NbN films with the same deposition conditions. Thermal annealings were performed up to 700 °C under vacuum in the 10−6 Torr range. Several properties of the coatings before and after these annealings were evaluated and compared, including hardness (nano‐indentation), adhesion/cohesion (scratch test), structure x‐ray diffraction, and composition Auger electron spectroscopy. The carbon nitride coatings lost part of their nitrogen, and both the hardness and the critical load dropped as the annealing temperature was increased. Carbon nitride films deposited on silicon wafers peeled off after treatment at 400 °C, while films deposited on an M1 steel remained adhered. A critical temperature for both chemical and physical properties around 600 °C was observed. For the TiN/NbN superlattice films, annealing up to 700 °C caused almost no intermixing, while the nitrogen content, the hardness, the adhesion/cohesion, and the structure remained unaffected.

Administration of typical antipsychotic drugs, such as haloperidol, promotes cAMP-dependent signaling in the medium spiny neurons (MSNs) of the striatum. In this study, we have examined the effect of haloperidol on the state of phosphorylation of the ribosomal protein S6 (rpS6), a component of the small 40S ribosomal subunit. We found that haloperidol increases the phosphorylation of rpS6 at the dual site Ser235/236, which is involved in the regulation of mRNA translation. This effect was exerted in the MSNs of the indirect pathway, which express specifically dopamine D2 receptors (D2Rs) and adenosine A2 receptors (A2ARs). The effect of haloperidol was decreased by blockade of A2ARs or by genetic attenuation of the Gα(olf) protein, which couples A2ARs to activation of adenylyl cyclase. Moreover, stimulation of cAMP-dependent protein kinase A (PKA) increased Ser235/236 phosphorylation in cultured striatal neurons. The ability of haloperidol to promote rpS6 phosphorylation was abolished in knock-in mice deficient for PKA activation of the protein phosphatase-1 inhibitor, dopamine- and cAMP-regulated phosphoprotein of 32 kDa. In contrast, pharmacological or genetic inactivation of p70 rpS6 kinase 1, or extracellular signal-regulated kinases did not affect haloperidol-induced rpS6 phosphorylation. These results identify PKA as a major rpS6 kinase in neuronal cells and suggest that regulation of protein synthesis through rpS6 may be a potential target of antipsychotic drugs.

International audience; Disruption of gene flow among demes after landscape fragmentation can facilitate local adaptation but increase the effect of genetic drift and inbreeding. The joint effects of these conflicting forces on the mean fitness of individuals in a population are unknown. Through simulations, we explored the effect of increased isolation on the evolution of genetic load over the short and long term when fitness depends in part on local adaptation. We ignored genetic effects on demography. We modeled complex genomes, where a subset of the loci were under divergent selection in different localities. When a fraction of the loci were under heterogeneous selection, isolation increased mean fitness in larger demes made up of hundreds of individuals because of improved local adaptation. In smaller demes of tens of individuals, increased isolation improved local adaptation very little and reduced overall fitness. Short-term improvement of mean fitness after fragmentation may not be indicative of the long-term evolution of fitness. Whatever the deme size and potential for local adaptation, migration of one or two individuals per generation minimized the genetic load in general. The slow dynamics of mean fitness following fragmentation suggests that conservation measures should be implemented before the consequences of isolation on the genetic load become of concern.

International audience; Drugs activating group III metabotropic glutamate receptors (mGluRs) represent therapeutic alternatives to L-DOPA (L-3,4-dihydroxyphenylalanine) for the treatment of Parkinson's disease (PD). Their presynaptic location at GABAergic and glutamatergic synapses within basal ganglia nuclei provide a critical target to reduce abnormal activities associated with PD. The effects of selective group III mGluR agonists (1S,3R,4S)-1-aminocyclopentane-1,3,4-tricarboxylic acid (ACPT-I) and L-()-2-amino-4-phosphonobutyric acid (L-AP4) infused into the globus pallidus (GP) or the substantia nigra pars reticulata (SNr) were thus studied in rat models of PD. Bilateral infusions of ACPT-I (1, 2.5, and 5 nmol/l) into the GP fully reverse the severe akinetic deficits produced by 6-hydroxydopamine nigrostriatal dopamine lesions in a reaction-time task without affecting the performance of controls. Similar results were observed after L-AP4 (1 nmol) or picrotoxin, a GABA A receptor antagonist, infused into the GP. In addition, intrapallidal ACPT-I counteracts haloperidol-induced catalepsy. This effect is reversed by concomitant administration of a selective group III receptor antagonist (RS)-cyclopropyl-4-phosphonophenylglycine. In contrast, ACPT-I (0.05, 0.1, and 0.25 nmol) infusions into the SNr enhance the lesion-induced akinetic deficits in control and lesioned rats and do not reverse haloperidol-induced catalepsy. L-AP4 (0.05 nmol) and picrotoxin in the SNr produce the same effects. Together, these results show that activation of group III mGluRs in the GP provides benefits in parkinsonian rats, presumably by modulating GABAergic neurotransmission. The opposite effects produced by group III mGluR activation in the SNr, also observed with a selective mGluR8 agonist, support the use of subtype-selective group III mGluR agonists as a potential antiparkinsonian strategy.

Accumulating evidence in humans demonstrated that visuo-spatial deficits are the most consistently reported cognitive abnormalities in Parkinson disease (PD). These deficits have been generally attributed to cortical dopamine degeneration. However, more recent evidence suggests that dopamine loss in the striatum is responsible for the visuo-spatial abnormalities in PD. Studies based on animal models of PD did not specifically address this question. Thus, the first goal of this study was to analyze the role of dopamine within the dorsal striatum in spatial memory. We tested bilateral 6-OHDA striatal lesioned CD1 mice in an object–place association spatial task. Furthermore, to see whether the effects were selective for spatial information, we measured how the 6-OHDA-lesioned animals responded to a non-spatial change and learned in the one-trial inhibitory avoidance task. The results demonstrated that bilateral (approximately 75%) dopamine depletion of the striatum impaired spatial change discrimination. On the contrary, no effect of the lesion was observed on non-spatial novelty detection or on passive avoidance learning. These results confirm that dopamine depletion is accompanied by cognitive deficits and demonstrate that striatal dopamine dysfunction is sufficient to induce spatial information processing deficits.

Yeasts lacking cytoplasmic superoxide dismutase (Cu,Zn-SOD) activity are permanently subjected to oxidative stress. We used two-dimensional PAGE to examine the proteome pattern of Saccharomyces cerevisiae strains lacking Cu,Zn-SOD. We found a new stable form of alkyl hydroperoxide reductase 1 (Ahp1) with a lower isoelectric point. This form was also present in wild type strains after treatment with tert-butyl hydroperoxide. In vitro enzyme assays showed that Ahp1p had lower specific activity in strains lacking Cu,Zn-SOD. We studied three mutants presenting a reduced production of the low pI variant under oxidative stress conditions. Two of the mutants (C62S and S59D) were totally inactive, thus suggesting that the acidic form of Ahp1p may only appear when the enzyme is functional. The other mutant (S59A) was active in vitro and was more resistant to inactivation by tert-butyl hydroperoxide than the wild type enzyme. Furthermore, the inactivation of Ahp1p in vitro is correlated with its conversion to the low pI form. These results suggest that in vivo during some particular oxidative stress (alkyl hydroperoxide treatment or lack of Cu,Zn-SOD activity but not hydrogen peroxide treatment), the catalytic cysteine of Ahp1p is more oxidized than cysteine-sulfenic acid (a natural occurring intermediate of the enzymatic reaction) and that cysteine-sulfinic acid or cysteine-sulfonic acid variant may be inactive.

The murine interferon-A11 (Mu IFN-A11) gene is a member of the IFN-A multigenic family. In mouse L929 cells, the weak response of the gene's promoter to viral induction is due to a combination of both a point mutation in the virus responsive element (VRE) and the presence of negatively regulating sequences surrounding the VRE. In the distal part of the promoter, the negatively acting E1E2 sequence was delimited. This sequence displays an inhibitory effect in either orientation or position on the inducibility of a virus-responsive heterologous promoter. It selectively represses VRE-dependent transcription but is not able to reduce the transcriptional activity of a VRE-lacking promoter. In a transient transfection assay, an E1E2-containing DNA competitor was able to derepress the native Mu IFN-A11 promoter. Specific nuclear factors bind to this sequence; thus the binding of trans-regulators participates in the repression of the Mu IFN-A11 gene. The E1E2 sequence contains an IFN regulatory factor (IRF)-binding site. Recombinant IRF2 binds this sequence and anti-IRF2 antibodies supershift a major complex formed with nuclear extracts. The protein composing the complex is 50 kDa in size, indicating the presence of IRF2 or antigenically related proteins in the complex. The Mu IFN-A11 gene is the first example within the murine IFN-A family, in which a distal promoter element has been identified that can negatively modulate the transcriptional response to viral induction.

In a context of Earth observation, spectral imagery allows a fine understanding of the observed scene. However, it generates a large amount of data which is generally processed afterwards in a ground station. In order to optimize the information flow, the paradigm of compressive sensing/sampling proposes to optically encode the incident light and to rely on processing to extract the semantic information of interest or to reconstruct the signal. This approach, which integrates optical systems and signal processing, requires new design methods and tools necessary for instrument development.This thesis deals with the joint design of an optical system, the CASSI double-disperser, and its associated algorithmic processing. Reflections were carried out on how to dimension the system as a whole, taking into account the close links between these two disciplines. It is necessary to use a design environment that allows to evaluate these interdependencies and to quickly test new optical and algorithmic configurations. A physical model has been proposed to describe the propagation of light through our instrument. It has been integrated into a compressed hyperspectral image acquisition simulator that includes various physical phenomena. This one interfaces easily with the data processing module, used to reconstruct the signal or extract semantic information.A prototype has been developed in order to explore the possibilities opened by these systems in an earth observation context. Particular attention has been paid to the adaptability of the optical encoding performed by the system. By basing ourselves on an array of micro-mirrors playing the role of spatial light modulator, the spectral filtering obtained is dynamic. It can thus adapt to the observed scene and allows the development of acquisition schemes specific to the missions that are entrusted to it. The experimental part of the thesis consisted in assembling, aligning and calibrating the optical system. Software and hardware tools have been developed to facilitate its realization., Dans un contexte d’observation de la Terre, l’imagerie spectrale permet une compréhension fine de la scène observée. Elle génère cependant une large quantité de données qui est généralement traitée à posteriori dans une station sol. En vue d’optimiser le flux d’informations, le paradigme de l’acquisition compressée propose d’encoder optiquement la lumière incidente et de s’appuyer sur des algorithmes de traitement pour extraire les informations sémantiques d’intérêt ou reconstruire le signal. Cette approche, qui intrique système optique et traitement du signal, nécessite de revoir les méthodes et outils de conception nécessaires au développement des instruments.La thèse porte sur la conception conjointe d’un système optique, le double-disperseur CASSI, et du traitement algorithmique qui lui est associé. Des réflexions ont été menées sur la manière de dimensionner le système dans sa globalité, en prenant en compte les liens étroits entre ces deux disciplines. Il convient d’utiliser un environnement de conception qui permette d’évaluer ces interdépendances et de tester rapidement de nouvelles configurations optiques et algorithmiques. Un modèle physique a été proposé pour décrire la propagation de la lumière à travers notre instrument. Il a été intégré à un simulateur d’acquisition d’images hyperspectrales compressées qui inclus divers phénomènes physiques. Celui-ci s’interface facilement avec le module de traitement des données, utilisé pour reconstruire le signal ou extraire des informations sémantiques.Un prototype a été développé dans le but d’explorer les possibilités ouvertes par ces systèmes dans un contexte d’observation de la terre. Une attention particulière a été portée à l’adaptativité de l’encodage optique effectuée par le système. En nous basant sur une matrice de micro-miroirs jouant le rôle du modulateur spatial de lumière, le filtrage spectral obtenu est dynamique. Il peut donc s’adapter à la scène observée et permet de mettre au point des schémas d’acquisitions spécifiques aux missions qui lui sont confiées. La partie expérimentale de la thèse a consisté à assembler, aligner puis étalonner le système optique. Des outils logiciels et matériels ont été développés pour faciliter sa réalisation.

National audience; In the context of Earth observation, spectral imagery provides a detailed understanding of the observed scene. However, it generates a large amount of data that must be processed afterwards in the ground stations. In order to optimise the information flow, the compressed sensing paradigm proposes to optically encode the incident light and to rely on processing algorithms to directly extract the semantic information of interest or to reconstruct the compressed signal. This approach, which integrates optical systems and digital information processing, requires modifications to the design methods and tools needed to develop the instruments.The thesis focuses on the joint design of an optical system, the CASSI double-disperser, and its associated algorithmic processing. Reflections have been made on how to dimension the system as a whole, taking into account the close links between these two disciplines. It is necessary to use a development environment that allows the evaluation of these interdependencies and the rapid testing of new optical and algorithmic configurations. A physical model has been proposed to describe the propagation of light through our instrument. It has been integrated into a compressed hyperspectral image acquisition simulator that includes various physical phenomena. This easily interfaces with the data processing module which is used to reconstruct the signal and/or extract semantic information.A prototype has been developed to explore the possibilities opened by these systems in an earth observation context. Particular attention was paid to the adaptability of the optical encoding performed by the system. By using an array of micro-mirrors as a spatial light modulator, the spectral filtering obtained is dynamic. It can therefore adapt to the observed scene and thus allow the development of acquisition schemes specific to the missions entrusted to the system. The experimental part of the thesis consisted of assembling, aligning and calibrating the optical system. Software and hardware tools were developed to facilitate the realisation of the prototype.Finally, a learning algorithm for the segmentation of compressed hyperspectral images was proposed and tested in simulation on earth observation data. The objective of this approach is to extract semantic information directly from the compressed measurements, without going through a reconstruction step of the hyperspectral image.; Dans un contexte d’observation de la Terre, l’imagerie spectrale permet une compréhension fine de la scène observée. Elle génère cependant une large quantité de données qui est doit être traitée à posteriori dans les stations sols. En vue d’optimiser le flux d’informations, le paradigme de l’acquisition compressée propose d’encoder optiquement la lumière incidente et de s’appuyer sur des algorithmes de traitement pour extraire les informations sémantiques d’intérêt ou pour reconstruire le signal compressé. Cette approche, qui intrique système optique et traitement numérique de l’information, nécessite de modifier les méthodes et outils de conception nécessaires au développement des instruments.La thèse porte sur la conception conjointe d’un système optique, le double-disperseur CASSI, et de son traitement algorithmique associé. Des réflexions ont été menées sur la manière de dimensionner le système dans sa globalité, en prenant en compte les liens étroits entre ces deux disciplines. Il convient d’utiliser un environnement de développement qui permette d’évaluer ces interdépendances et de tester rapidement de nouvelles configurations optiques et algorithmiques. Un modèle physique a été proposé pour décrire la propagation de la lumière à travers notre instrument. Il a été intégré à un simulateur d’acquisition d’images hyperspectrales compressées qui inclus divers phénomènes physiques. Celui-ci s’interface facilement avec le module de traitement des données, utilisé pour reconstruire le signal ou extraire des informations sémantiques.Un prototype a été développé dans le but d’explorer les possibilités ouvertes par ces systèmes dans un contexte d’observation de la terre. Une attention particulière a été portée à l’adaptativité de l’encodage optique effectuée par le système. En nous basant sur une matrice de micro-miroirs comme modulateur spatial de lumière, le filtrage spectral obtenu est dynamique. Il peut donc s’adapter à la scène observée et permet ainsi de mettre au point des schémas d’acquisitions spécifiques aux missions qui sont confiées au système. La partie expérimentale de la thèse a consisté à assembler, aligner puis étalonner le système optique. Des outils logiciels et matériels ont été développés pour faciliter la réalisation du prototype.Finalement, un algorithme d’apprentissage pour la segmentation d’images hyperspectrales compressées a été proposé puis testé en simulation sur des données d’observation de la terre. L’objectif de cette approche est d’extraire des informations sémantiques directement à partir des mesures compressées, sans passer par une étape de reconstruction de l’image hyperspectrale .