Implementation of Language and Literacy Practices by Prekindergarten Teachers in the West Virginia Universal Pre-K System

This study investigated the perceived frequency of implementation of language and literacy practices for 217 West Virginia Pre-K teachers. Teachers were employed in public school-based and community-based classrooms for 4-year-olds. Respondents completed the Language and Literacy Practice Survey (LLPS), which measured their perceived frequency of implementation of 18 language and literacy practices. Their overall perceived ability level for implementing effective language and literacy instruction was also assessed. Respondents also rated their use of resources and materials to facilitate effective language and literacy instruction. Additionally, respondents answered open-ended qualitative questions to determine perceived constraints that may hinder their effective implementation of language and literacy practices and to identify areas of additional support or professional development needed to enhance their ability to implement quality language and literacy instruction. Data were distinguished by three variables: preschool teaching experience, degree level and professional development clock hours completed. Results indicated that West Virginia Pre-K teachers perceived their overall ability to implement effective language and literacy instruction as Competent or Optimal. Likewise, their perceived frequency of implementation of the majority of associated language and literacy practices is Almost Always. Furthermore, their use of resources and materials corresponds with their perceived frequency of implementation. Practices associated with book selection and read-aloud activities were perceived to be implemented the most frequently of all 18 practices; whereas practices associated with writing and print awareness were perceived to have been the least effectively implemented. Moreover, the most significant indicator of perceived frequency of language and literacy implementation was the number of professional development clock hours completed. The qualitative data indicated that, of the constraints reported by West Virginia Pre-K teachers, the current curriculum (Creative Curriculum) and the lack of time were the most prominent. In addition, teachers indicated the strongest need for support or professional development in reading and writing practices, general language and literacy practices and early childhood best practices. The conclusions are that, overall, WV Pre-K teachers perceived themselves as implementing language and literacy instructional practices frequently and optimally and that they desire more professional development opportunities to improve the quality of their language and literacy practices

New Cardiovascular Indices Based on a Nonlinear Spectral Analysis of Arterial Blood Pressure Waveforms

A new method for analyzing arterial blood pressure is presented in this report. The technique is based on the scattering transform and consists in solving the spectral problem associated to a one-dimensional Schr\"odinger operator with a potential depending linearly upon the pressure. This potential is then expressed with the discrete spectrum which includes negative eigenvalues and corresponds to the interacting components of an N-soliton. The approach is similar to a nonlinear Fourier transform where the solitons play the role of sine and cosine components. The method provides new cardiovascular indices that seem to contain relevant physiological information. We first show how to use this approach to decompose the arterial blood pressure pulse into elementary waves and to reconstruct it or to separate its systolic and diastolic phases. Then we analyse the parameters computed from this technique in two physiological conditions, the head-up 60 degrees tilt test and the isometric handgrip test, widely used for studying short term cardiovascular control. Promising results are obtained

Short term control of the cardiovascular system: Assessment with the isometric handgrip exercise

This study aims at assessing the short term control of the Cardio Vascular system (CV), through a physiological test which involves strictly autonomic response: the handgrip isometric exercise, under vagal influence during the first minute. CVS parameters are extracted from RR and the arterial blood pressure (ABP) signals, respectively giving frequency and amplitude information on the CVS. Mean time series, spectral values and baroreflex sensitivity (BRS), seen as the spectral controller gain between RR and ABP, help to approach the underlying mechanisms of the autonomic control. Results give evidence of two major effects: - The relation between heart rate and contractility (positive staircase or Treppe effect). - The drop of BRS, due to the decrease of heart variability

A comparison of methods for delineation of wave boundaries in 12 Lead ECG

Présentation posterInternational audienceObjective: In the diagnosis of cardiac diseases, the delineation of electrocardiogram is crucial in order to efficiently classify cardiac events. Delineation consists in detecting the different peaks and boundaries of the QRS-complex, P-wave and T-wave. Several techniques have been proposed to face this issue. The objective is to assess the detection performances of a recent approach (non-negative matrix factorization) that has never been applied to ECG delineation and to compare its results with three known methods: morphological approach, discrete wavelet transform and difference operation method

New cardiovascular indices based on nonlinear spectral analysis of arterial blood pressure waveforms

A new method for analyzing arterial blood pressure is presented in this article. The technique is based on the scattering transform and consists in solving the spectral problem associated to a one-dimensional Schrödinger operator with a potential depending linearly upon the pressure. This potential is then expressed with the discrete spectrum which includes negative eigenvalues and corresponds to the interacting components of an N-soliton. The approach is similar to a nonlinear Fourier transform where the solitons play the role of sine and cosine components. The method provides new cardiovascular indices that seem to have meaningful physiological information, especially about the stroke volume and the ventricular contractility. We first show how to reconstruct the arterial blood pressure waves and separate its systolic and diastolic phases using this approach. Then we analyse the parameters computed from this technique in two physiological conditions, the head-up 60 degrees tilt test and the isometric handgrip test, widely used for studying short term cardiovascular control. Promising results are obtained

Arterial blood pressure analysis based on scattering transform I

This article presents a new method for analyzing arterial blood pressure waves. The technique is based on the scattering transform and consists in solving the spectral problem associated to a one-dimensional Schrödinger operator with a potential depending linearly upon the pressure. This potential is then expressed with the discrete spectrum which includes negative eigenvalues and corresponds to the interacting components of an N-soliton. The approach is analogous to the Fourier transform where the solitons play the role of sinus and cosinus components. The proposed method seems to have interesting clinical applications. It can be used for example to separate the fast and slow parts of the blood pressure that correspond to the systolic (pulse transit time) and diastolic phases (low velocity flow) respectively

An algorithm for robust and efficient location of T-wave ends in electrocardiogram

Computer-aided analysis of electrocardiogram (ECG) is widely used in cardiac disease diagnosis. The purpose of this paper is to propose a new algorithm for T-wave end location, which is known to be the most difficult one among ECG wave form detection and location problems. The proposed algorithm mainly consists of the computation of an indicator related to the area covered by the T-wave curve and delimited in a special manner. Based on simple assumptions, essentially on the concavity of the T-wave form, it is formally proved that the maximum of the computed indicator inside each cardiac cycle coincides with the T-wave end. Moreover, the algorithm is robust to measurement noise, to wave form morphological variations and to baseline wander. It is also computationally very simple: the main computation can be implemented as a simple finite impulse response (FIR) filter. When evaluated with the PhysioNet QT database in terms of the mean and the standard deviation of the \mbox{T-wave} end location errors, the proposed algorithm outperforms the other algorithms evaluated with the same data base, according to the most recent available publications up to our knowledge. \\ L'analyse de l'électrocardiogramme (ECG) assistée par l'ordinateur est largement utilisée en diagnostic de maladies cardiaques. Le but de cet article est de proposer un nouveau algorithme pour la localisation de fins d'ondes T, connu d'être le plus difficile des problèmes concernant la détection et localisation d'ondes dans l'ECG. L'algorithme proposé consiste principalement à calculer un indicateur lié à la surface couverte par l'onde T délimitée d'une manière spéciale. Sous des hypothèses simples, principalement sur la concavité de l'onde T, il est démontré que le maximum de l'indicateur calculé dans chaque cycle cardiaque coïncide avec la fin de l'onde T. En plus, l'algorithme est robuste au bruit de mesure, aux variations morphologiques et à la dérive de la ligne de base. Le calcul numérique est très simple : le calcul principal peut être implémenté sous forme d'un filtre à réponse impulsionnelle finie. Quand cet algorithme est évalué sur la base de données QT de PhysioNet en termes de la moyenne et l'écart type des erreurs de localisation de l'onde T, il obtient de meilleurs résultats par rapport à d'autres algorithmes évalués avec la même base de données, d'après les publications les plus récentes à notre connaissance

R-peak detection in holter ECG signals using non-negative matrix factorization

International audienceHolter monitoring is mainly used for medical follow- up and diagnosis of patients with suspected cardiac ar- rhythmia such as heart rhythm irregularities that can be missed during classical electrocardiogram recording (ECG). However, these long-term continuous recordings represent a large amount of data that cannot be processed by hand. In this article, we present a new method based on Non-negative Matrix Factorization (NMF) to detect R- peaks in Holter signals. The approach consists in two stages: source separation based on the different time- frequency patterns of the QRS complexes and the other waves of the signal (P and T waves) and R-peak detection using Automatic Objective Thresholding (AOT). The pro- posed approach is validated on the MIT-BIH Arrhythmia database and achieves an average sensitivity of 99.59% and a precision of 99.69%. Using the MIT-BIH Noise Stress Test database, we also show the ability of our ap- proach to discriminate R-peaks in signals contaminated with different noises