394 research outputs found

    Study of First-Order Thermal Sigma-Delta Architecture for Convective Accelerometers

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    This paper presents the study of an original closed-loop conditioning approach for fully-integrated convective inertial sensors. The method is applied to an accelerometer manufactured on a standard CMOS technology using an auto-aligned bulk etching step. Using the thermal behavior of the sensor as a summing function, a first order sigma-delta modulator is built. This "electro-physical" modulator realizes an analog-to-digital conversion of the signal. Besides the feedback scheme should improve the sensor performance.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/handle/2042/16838

    Impact of Technology Spreading on MEMS design Robustness

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    Dopamine interaction with a polyamine cryptand of 1H-pyrazole in the absence and in the presence of Cu(II) ions. Crystal structure of [Cu2(H21L](ClO4)3·2H2O

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    The crystal structure of the binuclear Cu2+ complex [Cu2(H21L)](ClO4)3·2H2O of the cryptand L = 1,4,7,8,11,14,17,20,21,24,29,32,33,36-tetradecaazapentacyclo[12.12.12.1^(6,9).1^(19,22),1,^31,34]hentetraconta-6,9(41),19(40), 21,31,34(39)-hexaene is presented; evidence for the formation in solution of binary L–dopamine and ternary Cu2+–L– dopamine complexes is presented.Escarti Alemany, Francisco, [email protected] ; Garcia-España Monsonis, Enrique, [email protected] ; Latorre Saborit, Julio, [email protected]

    Cu2+-Induced formation of cage-like compounds containing pyrazole macrocycles

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    The crystal structure of the complex [Cu4(H22L)2(H2O)2- (ClO4)2](ClO4)2·2H2O where L is a new pyrazole ligand containing 1,5-diaminopentane spacers represents a new form of obtaining metal ion-induced inorganic–organic cages.Escarti Alemany, Francisco, [email protected] ; Latorre Saborit, Julio, [email protected] ; Garcia-España Monsonis, Enrique, [email protected]

    On Infiltration and Infiltration Characteristic Times

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    In his seminal paper on the solution of the infiltration equation, Philip (1969), https://doi-org.proxy.library.uu.nl/10.1016/b978-1-4831-9936-8.50010-6 proposed a gravity time, tgrav, to estimate practical convergence time and the time domain validity of his infinite time series expansion, TSE, for describing the transient state. The parameter tgrav refers to a point in time where infiltration is dominated equally by capillarity and gravity as derived from the first two (dominant) terms of the TSE. Evidence suggests that applicability of the truncated two-term equation of Philip has a time limit requiring higher-order TSE terms to better describe the infiltration process for times exceeding that limit. Since the conceptual definition of tgrav is valid regardless of the infiltration model used, we opted to reformulate tgrav using the analytic implicit model proposed by Parlange et al. (1982), https://doi-org.proxy.library.uu.nl/10.1097/00010694-198206000-00001 valid for all times and related TSE. Our derived gravity times ensure a given accuracy of the approximations describing transient states, while also providing insight about the times needed to reach steady state. In addition to the roles of soil sorptivity (S) and the saturated (Ks) and initial (Ki) hydraulic conductivities, we explored the effects of a soil specific shape parameter β, involved in Parlange's model and related to the type of soil, on the behavior of tgrav. We show that the reformulated tgrav (notably urn:x-wiley:00431397:media:wrcr26009:wrcr26009-math-0001 where F(β) is a β-dependent function) is about three times larger than the classical tgrav given by urn:x-wiley:00431397:media:wrcr26009:wrcr26009-math-0002. The differences between the classical tgrav,Philip and the reformulated tgrav increase for fine-textured soils, attributed to the time needed to attain steady-state infiltration and thus i + infiltration for inferring soil hydraulic properties. Results show that the proposed tgrav is a better indicator of time domain validity than tgrav,Philip. For the attainment of steady-state infiltration, the reformulated tgrav is suitable for coarse-textured soils. Still neither the reformulated tgrav nor the classical tgrav,Philip are suitable for fine-textured soils for which tgrav is too conservative and tgrav,Philip too short. Using tgrav will improve predictions of the soil hydraulic parameters (particularly Ks) from infiltration data compared to tgrav,Philip

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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    Meeting abstrac

    Human IFN-γ immunity to mycobacteria is governed by both IL-12 and IL-23

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    Hundreds of patients with autosomal recessive, complete IL-12p40 or IL-12Rß1 deficiency have been diagnosed over the last 20 years. They typically suffer from invasive mycobacteriosis and, occasionally, from mucocutaneous candidiasis. Susceptibility to these infections is thought to be due to impairments of IL- 12–dependent IFN-? immunity and IL-23–dependent IL-17A/IL-17F immunity, respectively. We report here patients with autosomal recessive, complete IL- 12Rß2 or IL-23R deficiency, lacking responses to IL-12 or IL- 23 only, all of whom, unexpectedly, display mycobacteriosis without candidiasis. We show that aß T, ?d T, B, NK, ILC1, and ILC2 cells from healthy donors preferentially produce IFN-? in response to IL-12, whereas NKT cells and MAIT cells preferentially produce IFN-? in response to IL-23. We also show that the development of IFN-?–producing CD4+ T cells, including, in particular, mycobacterium-specific TH1* cells (CD45RA-CCR6+), is dependent on both IL-12 and IL-23. Last, we show that IL12RB1, IL12RB2, and IL23R have similar frequencies of deleterious variants in the general population. The comparative rarity of symptomatic patients with IL-12Rß2 or IL-23R deficiency, relative to IL-12Rß1 deficiency, is, therefore, due to lower clinical penetrance. There are fewer symptomatic IL-23R– and IL-12Rß2–deficient than IL-12Rß1–deficient patients, not because these genetic disorders are rarer, but because the isolated absence of IL-12 or IL-23 is, in part, compensated by the other cytokine for the production of IFN-?, thereby providing some protection against mycobacteria. These experiments of nature show that human IL-12 and IL-23 are both required for optimal IFN-?–dependent immunity to mycobacteria, both individually and much more so cooperatively

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    25th annual computational neuroscience meeting: CNS-2016

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    The same neuron may play different functional roles in the neural circuits to which it belongs. For example, neurons in the Tritonia pedal ganglia may participate in variable phases of the swim motor rhythms [1]. While such neuronal functional variability is likely to play a major role the delivery of the functionality of neural systems, it is difficult to study it in most nervous systems. We work on the pyloric rhythm network of the crustacean stomatogastric ganglion (STG) [2]. Typically network models of the STG treat neurons of the same functional type as a single model neuron (e.g. PD neurons), assuming the same conductance parameters for these neurons and implying their synchronous firing [3, 4]. However, simultaneous recording of PD neurons shows differences between the timings of spikes of these neurons. This may indicate functional variability of these neurons. Here we modelled separately the two PD neurons of the STG in a multi-neuron model of the pyloric network. Our neuron models comply with known correlations between conductance parameters of ionic currents. Our results reproduce the experimental finding of increasing spike time distance between spikes originating from the two model PD neurons during their synchronised burst phase. The PD neuron with the larger calcium conductance generates its spikes before the other PD neuron. Larger potassium conductance values in the follower neuron imply longer delays between spikes, see Fig. 17.Neuromodulators change the conductance parameters of neurons and maintain the ratios of these parameters [5]. Our results show that such changes may shift the individual contribution of two PD neurons to the PD-phase of the pyloric rhythm altering their functionality within this rhythm. Our work paves the way towards an accessible experimental and computational framework for the analysis of the mechanisms and impact of functional variability of neurons within the neural circuits to which they belong

    Conception et Test de Microsystèmes Monolithiques CMOS

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    Ce manuscrit présente une synthèse de mes activités de recherche depuis mon recrutement aux fonctions de maître de conférences à l'Université Montpellier II en 2001. Cette activité est développée au sein de l'équipe « Microsystèmes », dans le département « Microélectronique » du LIRMM.Le contenu de ce mémoire est organisé de façon à présenter pour chaque thème l'approche choisie et les résultats obtenus, en partant du dispositif élémentaire et en allant vers les aspects système, l'intégration et le test. Dans la section 2, je situe ces travaux dans leur contexte scientifique et dans leur chronologie afin à montrer l'évolution de notre démarche au fil des résultats obtenus. Le chapitre 3 est consacré à l'étude des dispositifs élémentaires. Les aspects liés à la modélisation, au prototypage et à la caractérisation y sont développés. Nous avons travaillé sur deux principes de transduction : les capteurs piézorésistifs et les capteurs thermiques. Notre expérience dans le domaine de la fiabilité est également abordée. Le chapitre 4 concerne la conception de systèmes microélectroniques à base de MEMS. Nos contributions s'appuient sur la réalisation de deux systèmes intégrés CMOS : une boussole et un capteur d'accélération thermique. A travers ces deux exemples, je montre nos résultats à la fois sur le plan des performances obtenues sur ces systèmes et sur des aspects plus méthodologiques de conception de MEMS. Je développe à la fin du manuscrit les perspectives de ces travaux et l'orientation de mes recherches pour les prochaines années
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