Sleep misperception is often observed in insomnia individuals (INS). The extent of misperception varies between different types of INS. The following paper comprised sections which will be aimed at ...studying the sleep EEG and compares it to subjective reports of sleep in individuals suffering from either psychophysiological insomnia or paradoxical insomnia and good sleeper controls. The EEG can be studied without any intervention (thus using the raw data) via either PSG or fine quantitative EEG analyses (power spectral analysis PSA), identifying EEG patterns as in the case of cyclic alternating patterns (CAPs) or by decorticating the EEG while scoring the different transient or phasic events (K-Complexes or sleep spindles). One can also act on the on-going EEG by delivering stimuli so to study their impact on cortical measures as in the case of event-related potential studies (ERPs). From the paucity of studies available using these different techniques, a general conclusion can be reached: sleep misperception is not an easy phenomenon to quantify and its clinical value is not well recognized. Still, while none of the techniques or EEG measures defined in the paper is available and/or recommended to diagnose insomnia, ERPs might be the most indicated technique to study hyperarousal and sleep quality in different types of INS. More research shall also be dedicated to EEG patterns and transient phasic events as these EEG scoring techniques can offer a unique insight of sleep misperception.
La mésestimation du sommeil est souvent observée chez les individus souffrant d’insomnie (INS). Cependant, l’ampleur de cette mésestimation varie entre les types d’INS. Cet article est composé de sections dédiées à l’étude de l’EEG et sa comparaison avec les rapports subjectifs de sommeil d’individus souffrant soit d’insomnie psychophysiologique ou paradoxale et bons dormeurs. L’EEG peut être étudié soit sans intervention (en utilisant les données brutes) comme dans le cas de la polysomnographie ou l’analyse spectrale, soit en identifiant des patrons d’activation comme pour les patrons cycliques alternants (cyclic alternating pattern) ou encore en décortiquant l’EEG en évènements phasiques ou transitoires (complexes-K et fuseaux de sommeil). On peut également agir sur l’EEG en délivrant des sons et en étudiant leur impact sur les ondes de l’EEG comme dans le cas des potentiels évoqués, et surtout ceux cognitifs. Du peu d’études disponibles utilisant ces différentes techniques/mesures, une conclusion générale peut tout de même être tirée : la mésestimation du sommeil n’est pas facilement quantifiable et sa valeur clinique n’est pas adéquatement reconnue. Alors qu’aucune des techniques/mesures définies ici n’est disponible ou recommandée afin de diagnostiquer l’insomnie, la technique utilisant les potentiels évoqués cognitifs semble la plus appropriée ou juste afin de mesurer l’hypervigilance corticale (hyperarousal) et la qualité du sommeil chez les différents types d’individus souffrant d’insomnie. Finalement, plus de recherches devraient être dédiées à l’étude des patrons EEG et des évènements phasiques du sommeil puisque ces techniques apportent une compréhension différemment unique de la mésestimation du sommeil.
The current mode line terminating input stage of an integrated circuit for the upgrade of the LHCb calorimeter front end electronics is presented. The circuit is based on a current mode input stage ...followed by two fully differential interleaved channels, namely a switched integrator and a track and hold. The input stage employs a novel electronically cooled input termination scheme to achieve stringent noise requirements. Compared to previous designs, its novelty relies in the use of two current feedback loops to decrease and control the input impedance of a common base stage. Two prototypes in Austriamicrosystems SiGe BiCMOS 0.35 μm technology have been designed and tested. Key measurements have been performed. Reflection coefficient is smaller than 0.5% for the full dynamic range, which is 12 bits. Relative linearity error is below 1%. Output noise is about 1 LSB after applying correlated double sampling.
This paper presents the design of the LHCb trigger and its performance on data taken at the LHC in 2011. A principal goal of LHCb is to perform flavour physics measurements, and the trigger is ...designed to distinguish charm and beauty decays from the light quark background. Using a combination of lepton identification and measurements of the particles' transverse momenta the trigger selects particles originating from charm and beauty hadrons, which typically fly a finite distance before decaying. The trigger reduces the roughly 11MHz of bunch-bunch crossings that contain at least one inelastic pp interaction to 3 kHz. This reduction takes place in two stages; the first stage is implemented in hardware and the second stage is a software application that runs on a large computer farm. A data-driven method is used to evaluate the performance of the trigger on several charm and beauty decay modes.
We present a solution made out of Components Out of Shelf (COTS) for the analog processing of the signal of the LHCb calorimeters in the framework of the foreseen upgrade of the detector. The present ...proposal is based on the current functional solution, yet, to meet the stringent noise requirements, a number of modifications are proposed. Preliminary results on the prototype boards show promising results.
LHCb is the experiment at the Large Hadron Collider at CERN designed for performing studies of CP-symmetry violation and rare decays of B-hadrons. Its calorimeter system allows to trigger on photons ...and electrons by associating the information from a scintillating pad signing charged particle (SPD), a pre-shower tagging electromagnetic particles (PS), an electromagnetic calorimeter (ECAL) and a hadronic calorimeter (HCAL). We present the principles and procedures for the fine time-alignment throughout the commissioning and the first collision phases. We give a particular emphasis to the choices made in the electronic design of the calorimeters to deal with the signal shape and spill over. Also we summarise the achieved levels of synchronisation.
A fully differential ASIC with cooled input termination is presented as a solution for the Upgrade of the Calorimeter front end electronics. The LHCb experiment needs to increase about ten times the ...integrated luminosity in order to study new physics. The increase in signal has to be compensated reducing the gain of the photomultipliers which implies stringent noise requirements. The proposed solution offers an active termination at the input and avoids the noise originated by the use of a resistor. The circuit is based on a two interleaved channel with a first amplifier stage, a switched integrator, and a Track-and-Hold. Two prototypes have been implemented and tested in SiGe BiCMOS 0.35um technology.
An integrated circuit for the Upgrade of the LHCb Calorimeter front end electronics is presented. The circuit is based on a current mode input stage followed by two fully differential interleaved ...channels with a switched integrator and a track and hold. The input stage employs a novel electronically cooled input termination scheme to achieve the stringent noise requirements. Compared to previous designs, its novelty relies in the use of two current feedback loops to decrease and control the input impedance of a common base stage. Two prototypes in AMS SiGe BiCMOS 0.35um technology have been designed and tested. Key measurements have been performed. Reflection coefficient is smaller than 0.5% for the full dynamic range, which is 12 bits. Relative linearity error is below 1%. Output noise is about 1 LSB after applying correlated double sampling.
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