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During an aging test of a high temperature proton exchange membrane fuel cell (HT-PEMFC) without exhaust pressure control loop, the anode and cathode pressures are dependent on variations in gas flow and atmospheric pressure. The voltage degradation rate is then impacted by atmospheric pressure variations. To extract the aging rate independently of the pressure, a possible solution is to estimate the voltage variation at a given pressure change. In this work, this voltage/pressure sensitivity was estimated in post-processing, by fitting regression planes (on measured voltage data) in the three dimensions: voltage, pressure, and time. It was applied on an aging test of 2753 h at 160 °C, at ambient pressure and at different constant currents (0.2, 0.4, and 0.6 A/cm2) which was carried out on an Advent Technologies Inc. PBI MEA of 45 cm2 active surface. The impact of varying atmospheric pressure on the calculation of degradation rates is then discussed and compared with another method developed in a previous work. It was found that a variation of 6 mV (2.4 % of initial voltage) at 1 A/cm2 during an aging test can be attributed to pressure variation alone, and not to cell degradation. Furthermore, it was observed that the voltage/pressure sensitivity is different depending on the period analyzed, at identical operating conditions (which would indicate that the dependence on pressure varies during aging). Indeed, at 0.2 A/cm2, the voltage response to a variation in pressure was quantified at approximately 50 μV/mbar and 80 μV/mbar at the start and end of life respectively. This method could therefore be used as an on-line diagnostic tool to monitor the fuel cell state of health. [Display omitted] • Aging test of a high temperature proton exchange membrane fuel cell for 2753 h. • Model of the impact of pressure and time on cell voltage. • Obtaining coefficients of the voltage variation against pressure and time. • Degradation rate can significantly be impacted by pressure variations only. • Method for post processing aging tests to correct the voltages against pressure. [ABSTRACT FROM AUTHOR]

Validation of the PVSQ self-report questionnaire (diagnosis) and the DHI-PC caregiver report questionnaire (Dizziness Handicap Inventory) aims to improve the management of pediatric vertigo, which is often under-diagnosed. The PVSQ and DHI-PC questionnaires were translated according to the Forward-Backward method and presented to a group of patients consulting for dizziness in a referral center and to a control group. A retest was performed at 2 weeks for both questionnaires. Statistical validation consisted in calculating discriminatory capacity, ROC curve, reproducibility and internal consistency. The main study objective was the translation and validation of the PVSQ and DHI-PC questionnaires in French. The secondary objectives were to compare results in two subgroups according to the vestibular or non-vestibular etiology of dizziness and to assess the correlation between the two questionnaires. In total, 112 children, in two comparable groups (53 cases and 59 controls), were included. Mean PVSQ score was 14.62 for cases and 6.55 for controls (P < 0.001). Reproducibility was moderate, and internal consistency and construct validity were satisfactory. A cut-off of 11 corresponded to maximum Younden index. Mean DHI-PC score was 41.6 (cases only). Reproducibility was moderate, and internal consistency and construct validity were satisfactory. The validation of the PVSQ and DHI-PC questionnaires offers two new tools in the management of dizziness, for both screening and follow-up. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efferocytosis is an important mechanism in the control of inflammatory processes. • In efferocytosis, mitochondrial fission and the oxidative stress process are linked. • This link occurs via ROS production and oxidative stress control. • Failed efferocytosis is key in the development of chronic inflammatory diseases. • These diseases include atherosclerosis and cardiometabolic pathology. In an adult human, billions of cells die and turn over daily. During this process, many apoptotic cells are produced and subsequently cleared by phagocytes – a process termed efferocytosis, which plays a critical role in tissue homeostasis. Efferocytosis is an important mechanism in the control of inflammatory processes. Efficient efferocytosis inhibits accumulation of apoptotic cells/debris and maintains homeostasis before the onset of necrosis (secondary necrosis), which promotes inflammation or injury. During efferocytosis, mitochondrial fission and the oxidative stress process are linked through reactive oxygen species production and oxidative stress control. Autophagy plays an important role in inhibiting inflammation and apoptosis, and in promoting efferocytosis by activated inflammatory cells, particularly neutrophils and macrophages. Autophagy in neutrophils is activated by phagocytosis of pathogens or activation of pattern recognition receptors. Autophagy is essential for major neutrophil functions, including degranulation, reactive oxygen species production, oxidative stress and release of neutrophil extracellular cytokines. Failed efferocytosis is a key mechanism driving the development and progression of chronic inflammatory diseases, including atherosclerosis, cardiometabolic pathology, neurodegenerative disease and cancer. Impairment of efferocytosis in apoptotic macrophages is a determinant of atherosclerosis severity and the vulnerability of plaques to rupture. Recent results suggest that inhibition of efferocytosis in the protection of the myocardium results in reduced infiltration of reparatory macrophages into the tissue, in association with oxidative stress reduction. Activated macrophages play a central role in the development and resolution of inflammation. The resolution of inflammation through efferocytosis is an endogenous process that protects host tissues from prolonged or excessive inflammation. Accordingly, therapeutic strategies that ameliorate efferocytosis control would be predicted to dampen inflammation and improve resolution. Thus, therapies targeting efferocytosis will provide a new means of treating and preventing cardiovascular and metabolic diseases involving the chronic inflammatory state. [ABSTRACT FROM AUTHOR]

Évaluer, sur la population des enfants et des adolescents, la validité d'un modèle de cercle vicieux de la stigmatisation de l'obésité qui, dans une compréhension psychopathologique, inclut les concepts de dépression et d'alimentation émotionnelle. Revue de question répertoriant les études publiées dans PubMed et PsychINFO avant 2005, portant sur des participants âgés de moins de 18 et incluant les différents facteurs du modèle (stigmatisation, dépression, alimentation émotionnelle et obésité). Dans l'état actuel des publications, le modèle n'a pas été validé dans sa globalité, notamment concernant le lien entre alimentation émotionnelle et d'une part la dépression, d'autre part la prise de poids. Cependant, l'existence d'une association bidirectionnelle « stigmatisation × obésité » a été confirmée. Cette association semble en partie médiée par des manifestations dépressives. Des études longitudinales doivent être entreprises afin de vérifier le rôle de l'alimentation émotionnelle dans le modèle. La santé mentale des enfants et des adolescents apparaît comme un facteur de risque de perpétuation du surpoids ou de l'obésité. Le phénomène de stigmatisation des enfants et adolescents de forte corpulence doit être une préoccupation centrale en termes de prévention et de prise en charge. To assess the validity of a vicious circle model of obesity stigma in the child and adolescent population that includes the concepts of depression and emotional eating in a psychopathological understanding. A review of studies published in PubMed and PsychINFO prior to 2005, involving participants under 18 years of age and including the different factors of the model (stigma, depression, emotional eating and obesity). In the current state of the literature, the model has not been validated in its entirety, particularly concerning the link between emotional eating and depression on the one hand and weight gain on the other. However, the existence of a bidirectional association "stigma × obesity" has been confirmed. This association seems to be partly mediated by depressive manifestations. Longitudinal studies should be undertaken to verify the role of emotional eating in the model. The mental health of children and adolescents appears to be a risk factor for the perpetuation of overweight or obesity. The phenomenon of stigmatization of overweight children and adolescents must be a central concern in terms of prevention and management. [ABSTRACT FROM AUTHOR]