25 research outputs found
48 – L’hyperplasie canalaire atypique à la macrobiopsie stéréotaxique mammaire : influence de la taille des aiguilles de biopsie sur le risque de sous-estimation
The BANCA Database and Evaluation Protocol
In this paper we describe the acquisition and content of a new large, realistic and challenging multi-modal database intended for training and testing multi-modal verification systems. The BANCA database was captured in four European languages in two modalities (face and voice). For recording, both high and low quality microphones and cameras were used. The subjects were recorded in three different scenarios, controlled, degraded and adverse over a period of three months. In total 208 people were captured, half men and half women. In this paper we also describe a protocol for evaluating verification algorithms on the database. The database will be made available to the research community through http://www.ee.surrey.ac.uk/Research/VSSP/banca
Low-temperature magnetic crossover in the topological kagome magnet TbMn6Sn6
Magnetic topological phases of quantum matter are an emerging frontier in physics and materials science, of which kagome magnets appear as a highly promising platform. Here, we explore magnetic correlations in the recently identified topological kagome system TbMnSnusing muon spin rotation, combined with local field analysis and neutron diffraction. Our studies identify an out-of-plane ferrimagnetic structure with slow magnetic fluctuations which exhibit a critical slowing down below ≃ 120 K and finally freeze into static patches with ideal out-of-plane order belowT ≃ 20 K. We further show that hydrostatic pressure of 2.1 GPa stabilises the static out-of-plane topological ferrimagnetic ground state in the whole volume of the sample. Therefore the exciting perspective arises of a magnetically-induced topological system whose magnetism can be controlled through external parameters. The present results will stimulate theoretical investigations to obtain a microscopic understanding of the relation between the low-temperature volume-wise magnetic evolution of the staticc-axis ferrimagnetic patches and the topological electronic properties in TbMnSn
Modulation of transforming growth factor beta signalling pathway genes by transforming growth factor beta in human osteoarthritic chondrocytes: involvement of Sp1 in both early and late response cells to transforming growth factor beta
International audienc
Adiponectin Upregulates Prolyl-4-Hydroxylase α1 Expression in Interleukin 6-Stimulated Human Aortic Smooth Muscle Cells by Regulating ERK 1/2 and Sp1
Adiponectin is an anti-atherogenic adipokine that inhibits the development of plaque by mechanisms that are not completely understood. Extracellular matrix (ECM) may have a role in the pathogenesis of atherosclerosis. We explored the effect and mechanisms of adiponectin on the synthesis of prolyl-4-hydroxylase (P4H) in interleukin 6 (IL-6)-stimulated human aortic smooth muscle cells (HASMCs). P4Hα1 mRNA level was quantified by RT-PCR, the protein levels of phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) and P4Hα1 were quantified by western blot analysis, and activation of specific protein 1 (Sp1) was determined by electrophoretic mobility shift assay and subcellular localization of Sp1 by immunofluorescence analysis. Adiponectin significantly increased P4Hα1 mRNA and protein levels in IL-6-stimulated HASMCs in a dose- and time-dependent manner. As well, ERK1/2 and Sp1 played a crucial role in the effect of adiponectin upregulating P4Hα1 expression in IL-6-stimulated HASMCs. Adiponectin abrogated the effects of IL-6 on collagen III level, which may indicate that P4Hα1 is essential for folding the procollagen polypeptide chains into stabilized collagen. Adiponectin attenuates IL-6–inhibited P4Hα1 synthesis and stabilizes collagen formation in HASMCs through a Sp1-ERK1/2-P4Hα1-dependent pathway
Spectrogram-based fundamental frequency tracking of spontaneous cries in preterm newborns
International audienceCry analysis of preterm newborns has proven to be relevant for prediction of pathologies or for comparison with full-term newborns. In this paper we propose a new approach for the automated detection and tracking of the fundamental frequency in cries, based on the processing of the spectrogram. A first step automatically detects the frequency bounds including the fundamental frequency along each cry. Then, the tracking of the fundamental frequency is obtained after a contour detection. Results showed that this new approach allows to process efficiently all types of cries. This whole procedure applied to a database including 1889 cries from 14 babies, at term-equivalent age, highlighted differences between extremely, very and late preterm as well as full-term newborns. In addition, we observed a decrease of the mean fundamental frequency with increasing gestational age, a result in accordance with the literature. © 2021 European Signal Processing Conference, EUSIPCO. All rights reserved
Automatic extraction of spontaneous cries of preterm newborns in neonatal intensive care units
International audienceCry analysis has been proven to be an inescapable tool to evaluate the development of preterm infants. However, to date, only a few authors proposed to automatically extract spontaneous cry events in the real context of Neonatal Intensive Care Units. In fact, this is challenging since a wide variety of sounds can also occur (e.g., alarms, adult voice). In this communication, a new method for spontaneous cry extraction from real life recordings of long duration is presented. A strategy based on an initial segmentation between silence and sound events, followed by a classification of the resulting audio segments into two classes (cry and non-cry) is proposed. To build the classification model, 198 cry events coming from 21 newborns and 439 non-cry events, representing the richness of the clinical sound environment were annotated. Then, a set of features, including Mel-Frequency Cepstral Coefficients, was computed in order to describe each audio segment. It was obtained after Harmonic plus Noise analysis which is commonly used for speech synthesis although never applied for newborn cry analysis. Finally, six machine learning approaches have been compared. K-Nearest Neighbours approach showed an accuracy of 94.1%. To experience the precision of the retained classifier, 412 hours of recordings of 23 newborns were also automatically processed. Results show that despite a difficult clinical context an automatic extraction of cry is achievable. This supports the idea that a new generation of non-invasive monitoring of neuro-behavioral development of premature newborns could emerge. © 2021 European Signal Processing Conference, EUSIPCO. All rights reserved
Optical characterization of YCa4O(BO3)3 and Nd:YCa4O(BO3)3 crystals
We report a complete optical characterization of YCa4O(BO3)3 and Nd:YCa4O(BO3)3 crystals. We studied the relative orientation between the dielectric and the crystallographic frames as a function of the wavelength and performed accurate phase-matching angles measurements for second harmonic generation, using a single crystal cut as a sphere. We also recorded polarized luminescence spectra of Nd:YCOB along the principal axes of the dielectric frame. For both crystals, we measured the gray-tracking and the thermo-optic properties as a function of temperature and wavelength using oriented slabs. Finally, we measured all their dielectric and electro-optic coefficients, as a function of frequency and wavelength