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Generating big-data is becoming imperative with the advent of machine learning. RIN-Neuroimaging Network addresses this need by developing harmonized protocols for multisite studies to identify quantitative MRI (qMRI) biomarkers for neurological diseases. In this context, image quality control (QC) is essential. Here, we present methods and results of how the RIN performs intra- and inter-site reproducibility of geometrical and image contrast parameters, demonstrating the relevance of such QC practice.American College of Radiology (ACR) large and small phantoms were selected. Eighteen sites were equipped with a 3T scanner that differed by vendor, hardware/software versions, and receiver coils. The standard ACR protocol was optimized (in-plane voxel, post-processing filters, receiver bandwidth) and repeated monthly. Uniformity, ghosting, geometric accuracy, ellipse's ratio, slice thickness, and high-contrast detectability tests were performed using an automatic QC script.Measures were mostly within the ACR tolerance ranges for both T1- and T2-weighted acquisitions, for all scanners, regardless of vendor, coil, and signal transmission chain type. All measurements showed good reproducibility over time. Uniformity and slice thickness failed at some sites. Scanners that upgraded the signal transmission chain showed a decrease in geometric distortion along the slice encoding direction. Inter-vendor differences were observed in uniformity and geometric measurements along the slice encoding direction (i.e. ellipse's ratio).Use of the ACR phantoms highlighted issues that triggered interventions to correct performance at some sites and to improve the longitudinal stability of the scanners. This is relevant for establishing precision levels for future multisite studies of qMRI biomarkers.

New data collection techniques offer numerical modelers the ability to gather and utilize high quality data sets with high spatial and temporal resolution. Such data sets are currently needed for calibration, verification, and to fuel future model development, particularly morphological simulations. This study explores the use of high quality spatial and temporal data sets of observed bed load transport in braided river flume experiments to evaluate the ability of a two-dimensional model, Delft3D, to predict bed load transport. This study uses a fixed bed model configuration and examines the model's shear stress calculations, which are the foundation to predict the sediment fluxes necessary for morphological simulations. The evaluation is conducted for three flow rates, and model setup used highly accurate Structure-from-Motion (SfM) topography and discharge boundary conditions. The model was hydraulically calibrated using bed roughness, and performance was evaluated based on depth and inundation agreement. Model bed load performance was evaluated in terms of critical shear stress exceedance area compared to maps of observed bed mobility in a flume. Following the standard hydraulic calibration, bed load performance was tested for sensitivity to horizontal eddy viscosity parameterization and bed morphology updating. Simulations produced depth errors equal to the SfM inherent errors, inundation agreement of 77–85%, and critical shear stress exceedance in agreement with 49–68% of the observed active area. This study provides insight into the ability of physically based, two-dimensional simulations to accurately predict bed load as well as the effects of horizontal eddy viscosity and bed updating. Further, this study highlights how using high spatial and temporal data to capture the physical processes at work during flume experiments can help to improve morphological modeling.

Assessment of the so-called “saturated-surface-dried” state shows a strong dependency on the test operator in the case of fine porous aggregates. This leads to low reliability and reproducibility of water absorption measurement for this family of particles. Evaporative methods for water absorption measurements seem to be a promising alternative. In this paper, we aim at evaluating the robustness and the limit of such methods while understanding the general underlying physical processes. We therefore measure the drying kinetics of non-porous and porous, real and model particles with various sizes and morphologies. We study specifically the unexpected effects of angularity and roughness of particles on drying rate changes over time. Our results suggest that this method is not suitable for all porous particles but shall apply well to crushed fine porous particles such as crushed sand and recycled sand.

We thoroughly benchmark the reliability of Cu-based CBRAM stacks with different switching layers against state-of-the-art OxRAM stacks. We optimize the switching conditions for maximizing the endurance lifetime in three CBRAM stacks, outlining the impact of the switching layer on the energy required for the switching operation and on the memory window. We show that CBRAM provide a larger memory window than OxRAM, but the switching energy is systematically higher, and the endurance lifetime is shorter. We also demonstrate that the larger memory window of CBRAM degrades over time and is thus only an apparent advantage with respect to OxRAM. Therefore, this study reveals that OxRAM devices investigated in this work are more suitable candidates than for applications targeting long data retention and low programming voltage.

Introduction Le syndrome d’apnees obstructives du sommeil (SAOS) est considere un facteur de risque cardiovasculaire. La fermeture repetee des voies aeriennes superieures pendant le sommeil declenche des phenomenes physiopathologiques responsables d’un desequilibre sympathovagal, mediateur central des consequences cardiovasculaires. Par contre, l’effet de la CPAP sur les complications cardiovasculaires reste controverse. Une explication proposee est que l’index d’apnees-hypopnees (IAH) pourrait etre insuffisant a representer les phenomenes a l’origine des effets cardiovasculaires. Notre objectif est de tester la capacite d’une manœuvre de deep breathing (DB) a montrer une dysfonction autonomique chez des patients SAOS, en comparaison aux analyses classiques de la variabilite du rythme cardiaque (HRV). Methodes Des sujets adresses pour suspicion de SAOS, sans pathologies ni traitement alterant le systeme nerveux autonome, sont inclus prospectivement. A l’eveil en position assise, 3 minutes d’enregistrement en ventilation spontanee et 3 minutes de DB (respiration ample a 6 par minute) precedent la polysomnographie. Nous analysons la HRV lors de la respiration spontanee et la variation du rythme cardiaque lors du DB (HRDB, moyenne des 5 variations consecutives les plus amples). Resultats 16 sujets (11 hommes, âge 44 ± 10 ans, index de masse corporelle 25 ± 4 kg/m2) sont inclus. L’HRDB etait plus bas chez les SAOS (IAH 17 ± 6) que chez les controles (IAH Conclusion Le deep breathing, methode applicable en pratique clinique, permet de mettre en evidence une dysfonction autonomique non detectee par les techniques usuelles d’analyse de la variabilite cardiaque chez des patients atteints de SAOS leger a modere. En association avec la polysomnographie, le deep breathing pourrait contribuer a identifier les patients SAOS a haut risque cardiovasculaire.

Le syndrome d’apnees obstructives du sommeil (SAOS) est une affection frequente dont la somnolence diurne est le symptome principal. Des comorbidites frequemment associees au SAOS (obesite, depression, …) peuvent participer a la somnolence. La pression positive continue (PPC) demeure le traitement de reference du SAOS, mais certains patients se plaignent toutefois de somnolence sous PPC. Ces patients necessitent une prise en charge systematisee qui amenera une minorite d’entre eux a un traitement medicamenteux de la somnolence.

In this paper, we assess the impact of different W oxidation conditions on the electrical performance of Cu/Al2O3/WOx-based CBRAM devices. While HR-TEM characterization carried out on samples with three different oxidation conditions reveals that WOx is always in the crystalline phase in our oxidation temperature range, higher oxidation temperature leads to denser and thicker oxides. By performing DC and AC electrical characterization, we demonstrate that a careful engineering of the W oxidation conditions enables to boost the performance of these devices. In particular, we prove that a trade-off between density and thickness must be pursued in order to enlarge the memory window and extend the endurance lifetime with short (10 ns) pulses.

In this paper we engineer a TiN⧹⧹Al2O3⧹⧹(Hf,Al)O2⧹⧹Ta2O5⧹⧹Hf Oxide Resistive Random Access Memory (OxRRAM) device for fast switching at low operation current without sacrificing the retention and endurance properties. The integrated 40 nm × 40 nm cell switches at 10 μA using write pulses shorter than 100 ns (resp. 1 μs) for Reset (resp. Set) and with amplitude

In this paper we outline the effects on the memory window of the programming method and pulse width and of the temperature, in Cu/Al2O3-based CBRAM targeting a 10-μA current regime. Despite its large median value, the overall HRS/LRS ratio in these devices can be drastically reduced due to the LRS and HRS dispersion and to the instability of the resistive states over time, especially in a low-current regime. For this reason, in this study we adopt a statistical approach, focusing on the tails of the cumulative distribution Function (CDF). We compare different verify-based algorithms to force an initial tail-to-tail (1st percentile of CDF) resistive window, demonstrating that, in order to reduce the total programming time, a complete Write/Erase cycle must be performed at each verify attempt. We also prove that the stability of the programmed LRS/HRS states is strongly influenced by the external temperature and that it is affected by the programming pulse width (PW) used in the algorithm, likely driving the diffusion processes that originate the state degradation. Selecting the appropriate PW, no overlap of the LRS and HRS distributions is observed after 1 week at room temperature.

Objectif Pour expliquer la surmortalite cardiovasculaire associee a la Ventilation Auto-Asservie (VAA) de l’etude SERVE-HF, il a ete evoque que les reglages de la VAA auraient induit une hyperventilation. Les objectifs de cette etude sont de decrire: – les reglages de la VAA et, – la ventilation minute (VM) en fonction de l’algorithme de la VAA (VAA-volume ResMed® et VAA-debit Philips®). Methodes Etude « vie reelle » transversale multicentrique incluant des patients traites par VAA depuis plus de 1 an, aucune consigne de reglage n’etant donnee aux 8 experts investigateurs. L’analyse des donnees est realisee: – en fonction du diagnostic initial du SAS (central, obstructif, emergent sous traitement), – en fonction de 5 clusters non supervises (partitionnement en K moyennes). Resultats 177 patients sont analyses avec une mediane (IQ25–75) d’IAH initial de 50 (38-62)/h, une duree de VAA de 2.88 (1.76–4,96) ans, 61,58 % traites par VAA-volume. Seule l’analyse basee sur les 5 clusters permet de mettre en evidence des differences entre clusters et/ou type de machine: – reglage d’une pression expiratoire (EPAP) fixe plus faible dans le groupe des patients obstructifs et a fraction d’ejection ventriculaire gauche reduite, – l’usage plus frequent de l’auto-EPAP chez les patients non cardiopathes, – des VM differents entre clusters, ces differences variant en fonction du type de VAA, – un risque d’hyperventilation quel que soit le cluster et le type de VAA. Conclusion Dans l’attente des etudes en cours, il serait prudent de telesuivre les donnees de VM des patients sous VAA.

International audience; 13 Recycled Concrete Aggregates are highly porous and may therefore absorb more water 14 than natural aggregates. Several methods allow for the measurement of water 15 absorption requiring drying at temperature above ambient conditions. We show here 16 that, for temperatures above the ambient temperature (> 30°C) and at low relative 17 humidity, the drying of recycled aggregates removes some bounded water contained in 18 hardened cement paste and increases both measured porosity and water absorption. 19 Porosity and XRD suggest that porosity increases due to ettringite dehydration. Thus, 20 the drying step required to characterize recycled aggregates leads to a systematic 21 overestimation of the water absorption. Moreover, this overestimation induces an error 22 in mix-design leading to a higher effective water/cement ratio. If absorption and water 23 content are measured with the same preparation protocol, correction is not needed. We 24 finally propose a correction method for the water absorption measured according to the 25 standard protocol (drying at 105°C).

A new viral disease named COVID-19 has recently turned into a pandemic. Compared to a common viral pneumonia it may evolve in an atypical way, causing the rapid death of the patient. For over two centuries, autopsy has been recognized as a fundamental diagnostic technique, particularly for new or little-known diseases. To date, it is often considered obsolete giving the inadequacy to provide samples of a quality appropriate to the sophisticated diagnostic techniques available today. This is probably one of the reasons why during this pandemic autopsies were often requested only in few cases, late and discouraged, if not prohibited, by more than one nation. This is in contrast with our firm conviction: to understand the unknown we must look at it directly and with our own eyes. This has led us to implement an autopsy procedure that allows the beginning of the autopsy shortly after death (within 1–2 h) and its rapid execution, also including sampling for ultrastructural and molecular investigations. In our experience, the tissue sample collected for diagnosis and research were of quality similar to biopsy or surgical resections. This procedure was performed ensuring staff and environmental safety. We want to propose our experience, our main qualitative results and a few general considerations, hoping that they can be an incentive to use autopsy with a new procedure adjusted to match the diagnostic challenges of the third millennium., Highlights • Early performed autopsy (within 1-2 hour from death) provides tissue samples for diagnosis and research of quality similar to biopsy or surgical resections. • Early samples collection reduces post-mortem artifacts, thus preventing the wrong interpretation of the morphological pictures observed. • Precise autopsy planning prevents risks for the staff.

The purpose of this study is to assess the reproducibility of hippocampal atrophy rate measurements of commonly used fully-automated algorithms in Alzheimer disease (AD). The reproducibility of hippocampal atrophy rate for FSL/FIRST, AdaBoost, FreeSurfer, MAPS independently and MAPS combined with the boundary shift integral (MAPS-HBSI) were calculated. Back-to-back (BTB) 3D T1-weighted MPRAGE MRI from the Alzheimer's Disease Neuroimaging Initiative (ADNI1) study at baseline and year one were used. Analysis on 3 groups of subjects was performed - 562 subjects at 1.5 T, a 75 subject group that also had manual segmentation and 111 subjects at 3 T. A simple and novel statistical test based on the binomial distribution was used that handled outlying data points robustly. Median hippocampal atrophy rates were -1.1%/year for healthy controls, -3.0%/year for mildly cognitively impaired and -5.1%/year for AD subjects. The best reproducibility was observed for MAPS-HBSI (1.3%), while the other methods tested had reproducibilities at least 50% higher at 1.5 T and 3 T which was statistically significant. For a clinical trial, MAPS-HBSI should require less than half the subjects of the other methods tested. All methods had good accuracy versus manual segmentation. The MAPS-HBSI method has substantially better reproducibility than the other methods considered.

The hippocampus has a key role in a number of neurodegenerative diseases, such as Alzheimer's Disease. Here we present a novel method for the automated segmentation of the hippocampus from structural magnetic resonance images (MRI), based on a combination of multiple classifiers. The method is validated on a cohort of 50 T1 MRI scans, comprehending healthy control, mild cognitive impairment, and Alzheimer's Disease subjects. The preliminary release of the EADC-ADNI Harmonized Protocol training labels is used as gold standard. The fully automated pipeline consists of a registration using an affine transformation, the extraction of a local bounding box, and the classification of each voxel in two classes (background and hippocampus). The classification is performed slice-by-slice along each of the three orthogonal directions of the 3D-MRI using a Random Forest (RF) classifier, followed by a fusion of the three full segmentations. Dice coefficients obtained by multiple RF (0.87 ± 0.03) are larger than those obtained by a single monolithic RF applied to the entire bounding box, and are comparable to state-of-the-art. A test on an external cohort of 50 T1 MRI scans shows that the presented method is robust and reliable. Additionally, a comparison of local changes in the morphology of the hippocampi between the three subject groups is performed. Our work showed that a multiple classification approach can be implemented for the segmentation for the measurement of volume and shape changes of the hippocampus with diagnostic purposes.

© 2015 Elsevier B.V. All rights reserved. The impact of different Ru precursors and/or deposition methods on the electrical characteristics of Ru/SrTiOx/Ru capacitors has been investigated. The observed increase of the leakage current density (Jg) and the equivalent oxide thickness (EOT) for ALD (atomic layer deposition) deposited Ru layers compared to PVD (physical vapor deposition) deposited ones was found to be caused by a SrRuTiOx layer formation at the SrTiOx/Ru interface aided by the presence of the oxygen co-reactant used during the ALD, regardless of the precursor used. publisher: Elsevier articletitle: Understanding the EOT–Jg degradation in Ru/SrTiOx/Ru metal–insulator–metal capacitors formed with Ru atomic layer deposition journaltitle: Microelectronic Engineering articlelink: http://dx.doi.org/10.1016/j.mee.2015.04.076 content_type: article copyright: Copyright © 2015 Elsevier B.V. All rights reserved. ispartof: Microelectronic Engineering vol:147 pages:108-112 ispartof: location:ITALY, Udine status: published

Display Omitted Metal-Insulator-Metal capacitors with strontium titanate and ruthenium electrodes.EOT=0.38nm @ 0V and current density 10-7Acm-2 @ ?1V and 25?C.J-V and C-V behavior modeled with defects and multi-phonon trap-assisted-tunneling.Relaxation measurement indicate charge loss of 6.5% @ 1s and 25?C. The electrical properties of Ru/SrTiOx/Ru capacitors have been investigated. Equivalent Oxide Thickness (EOT) of 0.38nm at 0V and current density of 10-7Acm-2 at ?1V and 25?C meet the sub-20nm DRAM requirements. Relaxation measurements were performed, indicating acceptable charge loss. Modeling of charge trapping at defect sites based on multi-phonon trap-assisted-tunneling quantitatively well describes leakage and capacitance behavior.