Search results for "processi"
showing 10 items of 9638 documents
Speech perception performance as a function of stimulus pulse rate and processing strategy preference for the Cochlear™ Nucleus®CI24RE device: Relati…
2010
Current cochlear implants can operate at high pulse rates. The effect of increasing pulse rate on speech performance is not yet clear. Habituation to low rates may affect the outcome. This paper presents the results of three subsequent studies using different experimental paradigms, applying the Nucleus CI24RE device, and conducted by ten European implant teams. Pulse rate per channel varied from 500 to 3500 pulses per second with ACE and from 1200 to 3500 pps with CIS strategy. The results showed that the first rate presented had little effect on the finally preferred rate. Lower rates were preferred. The effect of pulse rate on word scores of post-linguistic implantees was small; high rat…
Natural Proteolytic Processing of Hemofiltrate Cc Chemokine 1 Generates a Potent Cc Chemokine Receptor (Ccr)1 and Ccr5 Agonist with Anti-HIV Properti…
2000
Hemofiltrate CC chemokine (HCC)-1 is a recently described human chemokine that is constitutively expressed in numerous tissues and is present at high concentrations in normal plasma. Using a cell line expressing CC chemokine receptor (CCR)5 as a bioassay, we isolated from human hemofiltrate an HCC-1 variant lacking the first eight amino acids. HCC-1[9–74] was a potent agonist of CCR1, CCR3, and CCR5 and promoted calcium flux and chemotaxis of T lymphoblasts, monocytes, and eosinophils. It also blocked entry of HIV-1 strains using CCR5 as coreceptor. Limited tryptic digestion of HCC-1 generated the active variant. Conditioned media from several tumor cell lines activated HCC-1 with a high ef…
Temporal Structure of Human Gaze Dynamics Is Invariant During Free Viewing.
2015
We investigate the dynamic structure of human gaze and present an experimental study of the frequency components of the change in gaze position over time during free viewing of computer-generated fractal images. We show that changes in gaze position are scale-invariant in time with statistical properties that are characteristic of a random walk process. We quantify and track changes in the temporal structure using a well-defined scaling parameter called the Hurst exponent, H. We find H is robust regardless of the spatial complexity generated by the fractal images. In addition, we find the Hurst exponent is invariant across all participants, including those with distinct changes to higher or…
Normative data on the familiarity and difficulty of 196 Spanish word fragments
2005
In this article, normative data on the familiarity and difficulty of 196 single-solution Spanish word fragments are presented. The database includes the following indices: difficulty, familiarity, frequency, number of meanings, number of letters given in the fragment, first and/or last letters given, and ratio of letters to blanks. A factor analysis was performed on difficulty, and two factors were obtained. Frequency, familiarity, and number of meanings loaded highly on the first factor, which we consider to measure lexical processes, whereas number of letters in the fragment, first and/or last letters given, and ratio of letters to blanks loaded highly on the second factor, which we judge…
Automatic Detection of Left Ventricular Contours from Cardiac Cine Magnetic Resonance Imaging Using Fuzzy Logic
1999
Gated cardiac cine magnetic resonance imaging provides accurate dynamic data of the left ventricular function. However, the manual extraction of important physiologic parameters such as myocardium wall thickness and left ventricular volumes is invariably time consuming and subjective. To reduce the variability and time constraints inherent in observer contour tracing, the authors developed an automatic left ventricle contour-detection method.The purpose was to apply fuzzy logic-based automatic contour detection to identification of endocardial and epicardial borders in short-axis magnetic resonance images. The automatic contouring was compared with manual tracing using the calculated ejecti…
Ventricular Tachycardia and Early Fibrillation in Patients With Brugada Syndrome and Ischemic Cardiomyopathy Show Predictable Frequency-Phase Propert…
2015
[EN] Background¿ Ventricular fibrillation (VF) has been proposed to be maintained by localized high-frequency sources. We tested whether spectral-phase analysis of the precordial ECG enabled identification of periodic activation patterns generated by such sources. Methods and Results¿Precordial ECGs were recorded from 15 ischemic cardiomyopathy and 15 Brugada syndrome (type 1 ECG) patients during induced VF and analyzed in the frequency-phase domain. Despite temporal variability, induced VF episodes lasting 19.6±7.9 s displayed distinctly high power at a common frequency (shared frequency, 5.7±1.1 Hz) in all leads about half of the time. In patients with Brugada syndrome, phase analysis of …
Automatic determination of aortic compliance with cine-magnetic resonance imaging - An application of fuzzy logic theory
2002
International audience; Abstract: RATIONALE AND OBJECTIVES. Aortic compliance is defined as the relative change in aortic cross-sectional area divided by the change in arterial pressure. Magnetic resonance imaging (MRI) is a useful imaging modality for the noninvasive evaluation of aortic compliance. However, manual tracing of the aortic contour is subject to important interobserver variations. To estimate the aortic compliance from cine-MRI, a method based on fuzzy logic theory was elaborated. MATERIALS AND METHODS. Seven healthy volunteers and eight patients with Marfan syndrome were examined using an ECG gated cine-MRI sequence. The aorta was imaged in the transverse plane at the level o…
The internal calcar septum and its contact with the virtual stem in THR: a computer tomographic evaluation.
2003
The internal calcar septum is a ridge of cortical bone protruding from the inner cortical wall of the proximal femur into the medullary canal. It extends from the lesser trochanter into the femoral neck and narrows the femoral cavity in its dorsal third. This region is essential for THR stability, but the degree of contact between the septum and standard THR implants has never been studied. We obtained CT scans of 50 arthrotic hip joints from patients requiring THR. Virtual stems (50 straight/wedge-shaped and 50 anatomic stems) were placed in CT images of the femora using a PC-based preoperative planning unit. The dimensions of the septum, degree and location of contact between the septum a…
Hepatic Hilar and Sectorial Vascular and Biliary Anatomy in Right Graft Adult Live Liver Donor Transplantation
2008
Abstract Introduction The aim of this study was to analyze vascular and biliary variants at the hilar and sectorial level in right graft adult living donor liver transplantation. Methods From January 2003 to June 2007, 139 consecutive live liver donors underwent three-dimensional computed tomography (3-D CT) reconstructions and virtual 3-D liver partitioning. We evaluated the portal (PV), arterial (HA), and biliary (BD) anatomy. Results The hilar and sectorial biliary/vascular anatomy was predominantly normal (70%–85% and 67%–78%, respectively). BD and HA showed an equal incidence (30%) of hilar anomalies. BD and PV had a nearly identical incidence of sectorial abnormalities (64.7% and 66.2…
Macular edema computer-aided evaluation in ocular vein occlusions.
1998
This paper is concerned with the use of digital fundus imaging to detect, quantify, and follow up macular angiographic leakage due to retinal vein occlusions. Images were matched automatically. We detected those pixels with a high increment in gray level within the closest area to the foveal center. Binary images displaying leakage were obtained. The procedure was checked against two observers' agreement. Twenty-one angiographic studies were collected. Two images of each sequence were selected for digitalization. Numerical descriptors of the leakage were proposed and quantification plots were designed for each pair of images. Interobserver concordance ranged between 82 and 98% when manually…