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Fast camera imaging is used to study ion acoustic waves propagating azimuthally in a magnetized plasma column. The high-speed image sequences are analyzed using proper orthogonal decomposition and 2D Fourier transform, allowing to evaluate the assets and differences of both decomposition techniques. The spatiotemporal features of the waves are extracted from the high-speed images, which highlight energy exchanges between modes. Growth rates of the modes are extracted from the reconstructed temporal evolution of the modes, revealing the influence of ion-neutral collisions as pressure increases. Finally, the nonlinear interactions between modes are extracted using bicoherence computations, and they show the importance of interactions between modes with azimuthal wave numbers m, m -1, and -1, with m as an integer.(c) 2023 Author(s).

Purpose A James Lind Alliance priority setting partnership was developed to identify research priorities in breast cancer surgery from individuals with lived experience, at high genetic risk of breast cancer, and healthcare professionals (HCPs). Methods ‘Uncertainties’ were collected using an online survey. Following an evidence check and development of summary questions, an interim survey asked participants to rank their top 10 research priorities from the question list. Top-ranked questions from patient/carer, high-risk and professional groups were carried forward for discussion to a final online prioritisation workshop. Results 260 participants (101 patients/carers, 156 HCPs) submitted 940 uncertainties via the initial survey. These were analysed thematically into 128 summary questions in six topic areas. Following evidence checking, 59 questions were included in the interim survey which was completed by 572 respondents. Marked differences were seen in questions prioritised by patients/carers, HCPs and women at high-risk. The top eight priorities in patient/carer and professional groups and top two priorities for high-risk women were carried forward to the online workshop at which 22 participants discussed and agreed the final top 10. Key themes included de-escalation of breast and axillary surgery, factors impacting the development/detection of locoregional recurrence and optimal provision of support for informed treatment decision-making. Conclusion The top 10 research priorities in breast cancer surgery have been agreed. However, the observed differences in research priorities identified by patients and professional groups were not anticipated. Top priorities from both groups should inform future UK breast cancer surgical research, to ensure that it addresses questions that are important to breast cancer community as a whole.

International audience

Ammonia-rich lagoon supernatant was treated using anammox process in an integrated fixed-film activated sludge (IFAS) laboratory reactor. Effective anammox activities were demonstrated over 259 days of operation. The ammonium removal efficiency reached 94% in Phase I with influent concentrations of NH4+, NO2− and chemical oxygen demand (COD) at 250 mg-N/L, 325 mg-N/L, and 145 mg-COD/L, and reached 88% in Phase II at 420 mg-N/L, 525 mg-N/L, and 305 mg-COD/L. When supplemented with nitritation effluent for nitrite sources in Phase III, the influent COD concentration increased to 583 mg-COD/L without loss of ammonia removal efficiency (87%). The specific anammox activity was higher in biofilm than in the suspended flocs (P

This study investigates and compares the ammonia removal kinetics, attachment, biofilm development and anammox bacteria enrichment on various surface modified carriers throughout the 163 days of start-up of an MBBR system: virgin, dextran-functionalized carriers, silica-functionalized and pre-seeded denitrifying carriers. Silica-functionalized carriers along with pre-seeded denitrifying carriers induced significant higher kinetics, faster biofilm growth and greater anammox bacteria enrichment during the 64 days of operation compared to non-modified virgin and dextran-functionalized carriers. The elevated anammox bacteria counts along with the elevated kinetics of all carriers measured at day 106 indicated that the completed biofilm growth and biofilm maturation are achieved prior to or at day 106 of start-up. The NH4+-N removal rate for virgin, dextran-functionalized, silica-functionalized and pre-seeded denitrifying carriers were achieved 0.684 ± 0.019, 0.608 ± 0.016, 0.634 ± 0.017 and 0.665 ± 0.018 g NH4+-N/m2/d, respectively, at day 106. The results demonstrate that the silica-functionalized and pre-seeded denitrifying carriers offer advantages during the early stage of start-up while the dextran-functionalized carriers did not reduce the start-up period for anammox biofilm.

International audience; High-speed camera imaging is a powerful tool to probe the spatiotemporal features of unsteady processes in plasmas, usually assuming light fluctuations to be a proxy for the plasma density fluctuations. In this article, we systematically compare high-speed camera imaging with simultaneous measurements of the plasma parameters—plasma density, electron temperature, and floating potential—in a modestly magnetized Argon plasma column at low pressure (1 mTorr, magnetic fields ranging from 160 to 640 G). The light emission was filtered around 488 ± 5, 750 ± 5, and 810 ± 5 nm. We show that the light intensity cannot be interpreted as a proxy for the plasma density, and that the electron temperature cannot be ignored when interpreting high-speed imaging, both for the time-averaged profiles and for the fluctuations. The features of plasma parameter fluctuations are investigated, with a focus on ion acoustic waves (at frequency around 70 kHz) at low magnetic field and low-frequency azimuthal waves (around a few kHz) at larger magnetic fields. An excellent match is found between the high-speed images fluctuations and an Arrhenius law functional form, which incorporates fluctuations of the plasma density and of the electron temperature. These results explain the discrepancies between ion saturation current and narrow-band imaging measurements previously reported in the literature.

Obesity is a chronic multifactorial disease, characterized by a health-threatening accumulation of body fat and whose prevalence has been increasing worldwide since the 1980s. Obesity is a risk factor for type II diabetes, cardiovascular disease and various forms of cancer and is now a major public health issue. Unfortunately, available pharmacological treatments are rare and not very effective. Thus, the study of the biological mechanisms underlying body weight regulation could lead to the discovery of new therapeutic targets and prove useful in the fight against this modern curse. The brain plays a key role in controlling food intake and metabolism. In particular, some hypothalamic neurons called POMC neurons are classically described as being responsible for satiety. To date, most studies on these neurons have focused on their neuropeptide production, but recent discoveries have uncovered the existence of subpopulations, characterized by their ability to secrete different neurotransmitters (glutamate, GABA or both). The functional consequences of this heterogeneity are largely unknown to this day.The general objective of this thesis is to study the specific roles of different sub-populations of POMC neurons, depending on the neurotransmitter they release: we will then distinguish between POMC-Glut (pure glutamatergic), POMC-GABA (pure GABAergic) and POMC-Glut/GABA (mixed) neurons. Three objectives have been defined: To develop a new neuroanatomical technical approach to identify subpopulations of activated POMC neurons on mouse brain slices. To determine the impact of a hypercaloric diet on POMC subpopulations. To determine the role of the POMC Glutamatergic population in energy balance by using a novel genetic model. Results: First, we developed a new technique for the simultaneous detection of mRNAs of GAD65/67, vglut2 and POMC combined with an immunostaining of the cFos protein (a marker of cellular activity), in order to identify the subpopulations of activated POMC neurons under various experimental conditions. Then, we applied this technique in a context of an acute exposure to a high-calorie diet (HFD, for "high-fat-diet"). We then discovered that POMC-GABA neurons were the main sub-population to be activated by HFD, unlike POMC-Glut which were less likely to respond to the diet. Of note this preferential activation of POMC-GABA happens in a context of HFD-driven hyperphagia. Finally, we created a new genetically modified mouse line that allows the deletion of the vglut2 protein from POMC neurons in an inducible way, thus preventing the release of glutamate from POMC neurons. After carrying out the necessary controls, we conducted a metabolic characterization of this mouse line. Inducible POMC-vglut2-KO mice, in which POMC glutamatergic transmission is suppressed, have an exaggerated hyperphagic response following a 24-hour fast. In addition, when placed on a HFD, these mice eat more and have an increased energy expenditure. [...], L’obésité est une maladie chronique d’origine multifactorielle, caractérisée par une accumulation excessive de graisse corporelle néfaste pour la santé et dont la prévalence n’a cessé de croître au niveau mondial depuis les années 1980. Représentant un facteur de risque pour le diabète de type II, les maladies cardiovasculaires et différentes formes de cancer, l’obésité est aujourd’hui un enjeu majeur de santé publique. Malheureusement, les traitements pharmacologiques disponibles sont rares et peu efficaces. Ainsi, l’étude des mécanismes biologiques qui sous-tendent la régulation du poids corporel pourrait permettre de découvrir de nouvelles cibles thérapeutiques et se révéler utile dans la lutte contre ce fléau moderne. Le cerveau joue un rôle clé dans le contrôle de la prise alimentaire et du métabolisme. En particulier, certains neurones hypothalamiques, appelés neurones à POMC, sont classiquement décrits comme étant responsables de la satiété. Jusqu’alors, la plupart des études menées sur ces neurones se sont concentrées sur leur production de neuropeptides, mais de récentes découvertes ont mis à jour l’existence de sous-populations, caractérisées par leur capacité à sécréter différents neurotransmetteurs (glutamate, GABA ou les deux). Les conséquences fonctionnelles de cette hétérogénéité, jusqu’à alors largement insoupçonnée, sont à ce jour inconnues. L’objectif général de cette thèse est d’étudier le rôle spécifique de différentes sous-populations de neurones à POMC, en fonction du neurotransmetteur qu’ils libèrent : on distinguera alors les neurones à POMC-Glut (glutamatergiques purs), POMC-GABA (GABAergiques purs) et POMC-Glut/GABA (mixtes). Trois objectifs ont été définis : Développer une nouvelle technique de neuro-anatomie afin de détecter les différentes sous-populations de neurones à POMC activés, dans des coupes flottantes de cerveau de souris. Déterminer l’impact d’un régime hypercalorique sur les sous-populations de neurones à POMC. Déterminer le rôle des POMC-Glut dans la régulation de la balance énergétique à partir d’un nouveau modèle de souris génétiquement modifiées. Résultats : Tout d’abord, nous avons mis au point une nouvelle technique de détection simultanée des ARNm de GAD65/67, vglut2 et POMC combinée à un marquage de la protéine cFos (un marqueur d’activité cellulaire), afin d’identifier les différentes sous-populations de neurones à POMC activées dans diverses conditions expérimentales. Puis, nous avons mis en pratique cette technique lors d’une exposition aiguë à un régime hypercalorique (nommé HFD, pour « high-fat-diet »). Nous avons alors découvert que les neurones à POMC-GABA étaient la principale sous-population à être activée par le HFD, contrairement aux neurones à POMC-Glut qui étaient moins nombreux à y répondre. Cette activation préférentielle des POMC-GABA s’effectue de plus dans un contexte d’hyperphagie pour le HFD. Pour finir, nous avons créé une nouvelle lignée de souris génétiquement modifiées permettant la délétion inductible de la protéine vglut2 des neurones à POMC, empêchant ainsi la libération de glutamate des neurones à POMC. Après avoir effectué les contrôles nécessaires, nous avons entrepris une caractérisation métabolique de cette lignée. Les souris POMC-vglut2-KO inductibles, dont la transmission POMC glutamatergique est supprimée, ont une réponse hyperphagique exagérée suite à un jeûne de 24h. De plus, lorsqu’elles sont placées sous HFD, ces souris mangent davantage et ont une dépense énergétique augmentée. [...]

Objective Nutrient availability modulates reactive oxygen species (ROS) production in the hypothalamus. In turn, ROS regulate hypothalamic neuronal activity and feeding behavior. The mechanistic target of rapamycin complex 1 (mTORC1) pathway is an important cellular integrator of the action of nutrients and hormones. Here we tested the hypothesis that modulation of mTORC1 activity, particularly in Proopiomelanocortin (POMC)-expressing neurons, mediates the cellular and behavioral effects of ROS. Methods C57BL/6J mice or controls and their knockout (KO) littermates deficient either for the mTORC1 downstream target 70-kDa ribosomal protein S6 kinase 1 (S6K1) or for the mTORC1 component Rptor specifically in POMC neurons (POMC-rptor-KO) were treated with an intracerebroventricular (icv) injection of the ROS hydrogen peroxide (H2O2) or the ROS scavenger honokiol, alone or, respectively, in combination with the mTORC1 inhibitor rapamycin or the mTORC1 activator leptin. Oxidant-related signal in POMC neurons was assessed using dihydroethidium (DHE) fluorescence. Results Icv administration of H2O2 decreased food intake, while co-administration of rapamycin, whole-body deletion of S6K1, or deletion of rptor in POMC neurons impeded the anorectic action of H2O2. H2O2 also increased oxidant levels in POMC neurons, an effect that hinged on functional mTORC1 in these neurons. Finally, scavenging ROS prevented the hypophagic action of leptin, which in turn required mTORC1 to increase oxidant levels in POMC neurons and to inhibit food intake. Conclusions Our results demonstrate that ROS and leptin require mTORC1 pathway activity in POMC neurons to increase oxidant levels in POMC neurons and consequently decrease food intake., Graphical abstract, Highlights • H2O2 requires mTORC1 activity to increase oxidant levels in POMC neurons. • H2O2 requires functional mTORC1 in POMC neurons to inhibit food intake. • Leptin increases ROS-related signal in POMC neurons by engaging mTORC1. • Leptin requires functional mTORC1 in POMC neurons to inhibit food intake.

National audience

UMR BFP - Equipe Virologie; International audience

National audience

Cet état des lieux de la gestion des végétaux en stations de traitement des eaux usées à filtres plantés de roseaux répond à une demande des gestionnaires de ce type de stations. En effet, les services d’assistances techniques départementaux, Irstea (INRAE) ou l’OIEau sont régulièrement questionnés quant aux techniques d’éradication du liseron, aux traitements contre les pucerons ou encore au devenir des roseaux faucardés chaque année. Or, ces questionnements ne trouvent parfois pas de réponse localement, alors qu’il existe des solutions testées par ailleurs et ayant fait leurs preuves, seules ou combinées, avec une efficacité partielle ou totale. C’est la raison pour laquelle un recueil d’informations au niveau national a été entrepris en 2018, afin de recenser les problématiques et les solutions testées en France métropolitaine de manière exhaustive. Il s'agit dans un premier temps de synthétiser les expériences existantes dans un document diffusé largement par le biais du groupe de travail EPNAC (et sur le site https://epnac.fr/).