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Abstract This paper presents a novel four-terminal variable capacitor (FTVC) dedicated to the recent concept of low power capacitive adiabatic logic (CAL). This FTVC is based on silicon nano/micro technologies and is intended to achieve adiabatic logic functions with a better efficiency that by using field effect transistor (FET). The proposed FTVC consists of two capacitors mechanically coupled and electrically isolated, where a comb-drive input capacitor controls a gap-closing capacitor at the output. To fully implement the adiabatic combinational logic, we propose two types of variable capacitors: a positive variable capacitor (PVC) where the output capacitance value increases with the input voltage, and a negative variable capacitance (NVC) where the output capacitance value decreases when the input voltage increases. A compact and accurate electromechanical model has been developed. The electromechanical simulations demonstrate the ability of the proposed FTVC devices for CAL, with improved features such as high logic states differentiation larger than 50% of the full-scale input signal and cascability of both buffers and inverters. Based on the presented analysis, 89% of the total injected energy in the device can be recovered, the remaining energy being dissipated through mechanical damping. During one cycle of operation, a buffer gate of 10 × 2.5 µm2 dissipates only 0.9 fJ. Graphic abstract In this paper, we presented two novel four-terminal variable capacitors (FTVC) to be implemented in capacitive adiabatic logic (CAL). The proposed FTVC allow to drastically reduce the non-adiabatic dissipations associated to FET transistors. They are based on silicon nano/micro technologies and consists in two capacitors mechanically coupled and electrically isolated, where a comb-drive input capacitor controls a gap-closing capacitor at the output. We developed a complete electromechanical model of the FTVC that demonstrated the recovery of 89% of the injected energy and the cascade ability of the proposed FTVC devices for the CAL with a logic states differentiation as high as 55%. fx1 Highlights • We report a novel four-terminal variable capacitor (FTVC) dedicated to the capacitive adiabatic logic (CAL). • The proposed FTVC has high logic states differentiation and cascability of both buffers and inverters. • 89% of the total injected energy can be recovered and a buffer gate of 10 × 2.5 µm2 dissipates only 0.9 fJ per cycle. [ABSTRACT FROM AUTHOR]

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Résumé Les arboviroses, des maladies virales transmises par des arthropodes hématophages, sont responsables de syndromes fébriles parfois accompagnés de manifestations hémorragiques ou neurologiques. Les activités humaines ont favorisé l’émergence de ces virus, originellement zoonotiques, la domestication des principaux vecteurs et leur dissémination à travers le monde. L’épidémiologie des arboviroses, transmises par des moustiques du genre Aedes , a connu d’importantes modifications au cours de la dernière décennie, notamment en lien avec la dissémination intercontinentale d’ Aedes albopictus . Nous abordons ici les conséquences épidémiologiques de l’invasion par cette espèce de l’Afrique centrale et de l’Europe dans un contexte de globalisation des virus. Dans ces zones, le risque de transmission est modulé par des phénomènes d’adaptation virus-vecteurs ainsi que par des phénomènes environnementaux tels que les facteurs climatiques. Face à ces nouveaux risques, il est primordial de développer les capacités de veilles entomologique et virologique, d’évaluation du risque, d’anticipation des risques épidémiques afin de développer de stratégies de prévention et de contrôle des épidémies. Arboviruses – viruses transmitted by haematophagous arthropods – are responsible for febrile syndromes, which sometimes include haemorrhagic or neurological symptoms. Human activities have facilitated the emergence of these originally zoonotic viruses and the domestication and spread throughout the world of their major vectors. The last decade has seen significant changes in the epidemiology of arboviruses transmitted by mosquitoes of the genus Aedes , particularly in relation to the intercontinental spread of Aedes albopictus . Here, we address the epidemiological consequences of the invasion by this species into Central Africa and Europe in a context of viral globalization. The risk of transmission in these areas is influenced by virus-vector adaptation phenomena as well as environmental phenomena including climate. Faced with these new risks, it is essential to develop competences in entomological and virological surveillance, risk assessment and forecasting of epidemic risk in order to develop strategies for the prevention and control of epidemics. [ABSTRACT FROM AUTHOR]

Abstract: Caffeine is a widely used psychostimulant freely crossing the placental barrier. At the doses usually absorbed, it acts as an antagonist of both A1 and A2A adenosine receptors. Pregnant women are generally not advised to limit their caffeine consumption and thus expose their progeny to the drug during the whole of gestation and lactation. The possibility that such caffeine exposure may have long-term consequences on brain development has led to several behavioral investigations on animal models. Despite the crucial role played by adenosine receptor systems in neonatal breathing control, few studies in vitro have been concerned with the consequences of maternal caffeine absorption on breathing, and none in the unrestrained intact animal. The present investigation analyzed the influence of caffeine exposure via placental and milk transfer on resting ventilation and on the response to moderate alveolar hypoxia of 0 to 2-day-old newborn rat (P0–P2) together with the possible underlying mechanisms. Dams absorbed caffeine (46±3 mg/kg/day) via drinking fluid (0.2 g/L) throughout gestation, in conditions mimicking moderate human consumption. Caffeine exposure did not significantly affect basal respiratory parameters. In contrast, it attenuated both the early increase and the secondary decrease in ventilation triggered by moderate alveolar hypoxia (11% O2 inhaled). The abolition of Fos protein expression evoked by hypoxia suggested that caffeine exposure may decrease the activity of O2-sensing peripheral chemoreceptor pathway. From real-time PCR data, those functional alterations were associated to increases in A2A adenosine receptor and α2 GABAA receptor subunit mRNAs in the medulla. This indicates that, even at moderate doses, maternal caffeine consumption may induce a series of subtle developmental alterations that may affect modulation of breathing control in the neonate in pathological situations such hypoxia. [Copyright &y& Elsevier]