Search results for "speckle"
showing 10 items of 123 documents
Hybrid optical-digital method for local-displacement analysis by use of a phase-space representation.
2010
A method for evaluating the local deformation or displacement of an object in speckle metrology is described. The local displacements of the object in one direction are digitally coded in a one-dimensional specklegram. By optically performing the local spectrum of this pattern, one simultaneously achieves information about the local displacement and its spatial position. The good performance of this technique is demonstrated with computer-generated test signals.
Stepping stones of life: natal dispersal in the group-living but noncooperative speckled warbler
2003
In most cooperatively breeding birds the offspring of one sex, usually male, delays dispersal to remain on the natal territory and helps its parents to rear subsequent young. Thus delayed dispersal could be the first step in the evolution of cooperative breeding. We studied natal dispersal in a population of the group-living speckled warbler, Chthonicola sagittata, based on observations of a colour-banded population over 3 years. Unlike other group-living members of the Acanthizinae, all juvenile males in this population dispersed to settle on foreign territories as subordinates, which do not help rear the young. Speckled warblers showed all the life history traits that are thought to resul…
Analisi sperimentale delle tensioni con la fotomeccanica
2009
Classification of SD-OCT Volumes Using Local Binary Patterns: Experimental Validation for DME Detection
2016
International audience; This paper addresses the problem of automatic classification of Spectral Domain OCT (SD-OCT) data for automatic identification of patients with Diabetic Macular Edema (DME) versus normal subjects. Optical Coherence Tomography (OCT) has been a valuable diagnostic tool for DME, which is among the most common causes of irreversible vision loss in individuals with diabetes. Here, a classification framework with five distinctive steps is proposed and we present an extensive study of each step. Our method considers combination of various pre-processings in conjunction with Local Binary Patterns (LBP) features and different mapping strategies. Using linear and non-linear cl…
Non‐uniform displacement within ruptured Achilles tendon during isometric contraction
2021
The purpose of this study was investigate tendon displacement patterns in non‐surgically treated patients 14 months after acute Achilles tendon rupture (ATR) and to classify patients into groups based on their Achilles tendon (AT) displacement patterns. Twenty patients were tested. Sagittal images of AT were acquired using B‐mode ultrasonography during ramp contractions at a torque level corresponding to 30% of the maximal isometric plantarflexion torque of the uninjured limb. A speckle tracking algorithm was used to track proximal‐distal movement of the tendon tissue at 6 antero‐posterior locations. Two‐way repeated measures ANOVA for peak tendon displacement was performed. K‐means cluster…
Introduzione all'analisi sperimentale delle tensioni
2009
Speckle tracking analysis in intensive care unit: A toy or a tool?
2018
The use of conventional echocardiography in the intensive care unit (ICU) is today established to assess left and right ventricular systolic function, for preload determination and procedural guidance. Next step in ICU echocardiography could be the use of novel ultrasound techniques such as strain echocardiography to assist in the management of patients with acute coronary syndrome, heart failure, or pulmonary embolism. This review has gathered the available evidence supporting the incremental value of strain in the diagnostic workup of cardiac diseases treated in ICU.
P776 Stress ecocardiography and speckle tracking analysis in patients with heart failure and preserved ejection fraction
2020
Abstract BACKGROUND Heart failure with preserved ejection fraction (HFpEF) is characterized by heart failure symptoms despite preserved LV systolic function together with at least one among left ventricle hypertrophy/left atrial enlargement plus diastolic dysfunction (DD) and increased brain natriuretic peptide levels. Rest echocardiography could still be normal despite patients experience HF symptoms. Speckle tracking analysis (STE) analyzes myocardial deformation and is able to identify subtle left ventricular dysfunction. PURPOSE to analyze the added value of stress echocardiography to improve diagnostic accuracy in patients with normal ejection fraction and unexplained dyspnoea by evalu…
Mobile platform for online processing of multimodal skin optical images: Using online Matlab server for processing remission, fluorescence and laser …
2015
Mobile platform for multimodal skin assessment has been developed. Different illumination sources allow switching between modalities. Diffuse reflectance spectral imaging is provided by five LEDs, fluorescence is excited by 405 nm LEDs, and laser speckle by 650 nm laser diode. Handheld, battery powered device includes all light sources and color camera with USB. The core of the system is Linux OS embedded microcontroller. USB, FTP and HTML with JavaScript combination is used to create standard image transfer and control interface. In combination with built in WiFi access point it allows online skin images storage and processing. It means that data processing algorithms are located and updat…
1232 Acute myocarditis: prognostic role of speckle tracking echocardiography and cardiac magnetic resonance
2020
Abstract Background Myocarditis is an inflammatory disease of the myocardium predominantly caused by infection with subsequent immunological response. Cardiac magnetic resonance (CMR) is the currently best imaging modality to confirm a suspected diagnosis of myocarditis. Conventional echocardiography can detect regional or global wall motion abnormalities but it could also be negative. Speckle tracking echocardiography can help to identify subtle systolic dysfunction, in patients with myocardits and apparently negative echocardiogram. Purpose the aim of this study was to identify cardiac imaging parameters predictive of cardiovascular events in patients with acute myocarditis. Methods a pro…