Search results for "methods [Diffusion Tensor Imaging]"

Bagging and Boosting with Dynamic Integration of Classifiers

2000

One approach in classification tasks is to use machine learning techniques to derive classifiers using learning instances. The co-operation of several base classifiers as a decision committee has succeeded to reduce classification error. The main current decision committee learning approaches boosting and bagging use resampling with the training set and they can be used with different machine learning techniques which derive base classifiers. Boosting uses a kind of weighted voting and bagging uses equal weight voting as a combining method. Both do not take into account the local aspects that the base classifiers may have inside the problem space. We have proposed a dynamic integration tech…

Coherence between brain activation and speech envelope at word and sentence levels showed age-related differences in low frequency bands

2021

Abstract Speech perception is dynamic and shows changes across development. In parallel, functional differences in brain development over time have been well documented and these differences may interact with changes in speech perception during infancy and childhood. Further, there is evidence that the two hemispheres contribute unequally to speech segmentation at the sentence and phonemic levels. To disentangle those contributions, we studied the cortical tracking of various sized units of speech that are crucial for spoken language processing in children (4.7–9.3 years old, N = 34) and adults (N = 19). We measured participants’ magnetoencephalogram (MEG) responses to syllables, words, and…

First M87 Event Horizon Telescope Results. IV. Imaging the Central Supermassive Black Hole

2019

We present the first Event Horizon Telescope (EHT) images of M87, using observations from April 2017 at 1.3 mm wavelength. These images show a prominent ring with a diameter of ~40 μas, consistent with the size and shape of the lensed photon orbit encircling the "shadow" of a supermassive black hole. The ring is persistent across four observing nights and shows enhanced brightness in the south. To assess the reliability of these results, we implemented a two-stage imaging procedure. In the first stage, four teams, each blind to the others' work, produced images of M87 using both an established method (CLEAN) and a newer technique (regularized maximum likelihood). This stage allowed us to av…

La circulation des objets métalliques à l'âge du Bronze entre Rhône et Saône: utilisation d'une transformation cartographique linéaire

2006

In order to gain a better understanding of circulation flows of metal objects during the Bronze Age, and move beyond traditional distribution maps of archaeological discoveries, the authors propose a more quantitative and concise method of graphic representation, namely cartographic linear transformation. The value of the method was tested on the Saône-Rhône axis. Bronze axes, swords and daggers were recorded along a 50 km strip either side of the river axis, in order to estimate the frequency and mass of objects in “circulation”.

The Rise and Fall of Business Firms: A Stochastic Framework on Innovation, Creative

2021

FPGA implementation of a deep learning algorithm for real-time signal reconstruction in particle detectors under high pile-up conditions

2019

The analog signals generated in the read-out electronics of particle detectors are shaped prior to the digitization in order to improve the signal to noise ratio (SNR). The real amplitude of the analog signal is then obtained using digital filters, which provides information about the energy deposited in the detector. The classical digital filters have a good performance in ideal situations with Gaussian electronic noise and no pulse shape distortion. However, high-energy particle colliders, such as the Large Hadron Collider (LHC) at CERN, can produce multiple simultaneous events, which produce signal pileup. The performance of classical digital filters deteriorates in these conditions sinc…

Devenir chercheur ou enseignant chercheur : le goût pour la recherche des doctorants à l'épreuve du marché du travail

2016

Faire une thèse pour devenir chercheur ou enseignant-chercheur est souvent considéré comme un parcours difficile dont le résultat est incertain. Plus que dans d’autres pays, les diplômés de doctorat en France connaissent de fortes difficultés de stabilisation sur le marché du travail. Notre recherche s’interroge sur les raisons qui conduisent les jeunes à obtenir un doctorat puis à choisir une carrière de chercheur ou d’enseignant-chercheur et enfin, à s’y stabiliser. À partir d’une enquête du Céreq, nos résultats montrent que l’intérêt pour la recherche qu’ils ont manifesté dès le début des études supérieures et le capital social vont fortement structurer leur parcours universitaire et pro…

Absolute and relative quantification of RNA modifications via biosynthetic isotopomers

2014

In the resurging field of RNA modifications, quantification is a bottleneck blocking many exciting avenues. With currently over 150 known nucleoside alterations, detection and quantification methods must encompass multiple modifications for a comprehensive profile. LC-MS/MS approaches offer a perspective for comprehensive parallel quantification of all the various modifications found in total RNA of a given organism. By feeding (13)C-glucose as sole carbon source, we have generated a stable isotope-labeled internal standard (SIL-IS) for bacterial RNA, which facilitates relative comparison of all modifications. While conventional SIL-IS approaches require the chemical synthesis of single mod…

Star Image Identification and Characterization on Astrographic Plates

1994

The automatic identification and characterization of star images has great value for the preliminary analysis and measurement of astrographic plates. Our group at Valencia Observatory is using a small 2-D stage and a CCD camera under computer control to perform systematic measurements of bright asteroid plates. We are also applying this method to the processing of astrographic plates with crowded stellar fields and non-stellar objects in collaboration with the Pulkovo Observatory.

Computational identification of cell-specific variable regions in ChIP-seq data.

2019

ABSTRACT Chromatin immunoprecipitation followed by sequencing (ChIP-seq) is used to identify genome-wide DNA regions bound by proteins. Several sources of variation can affect the reproducibility of a particular ChIP-seq assay, which can lead to a misinterpretation of where the protein under investigation binds to the genome in a particular cell type. Given one ChIP-seq experiment with replicates, binding sites not observed in all the replicates will usually be interpreted as noise and discarded. However, the recent discovery of high-occupancy target (HOT) regions suggests that there are regions where binding of multiple transcription factors can be identified. To investigate these regions,…