Search results for " tracking"
showing 10 items of 431 documents
Diagnostic potential of the diffusion tensor tractography with fractional anisotropy in the diagnosis and treatment of cervical spondylotic and postt…
2016
Background: Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI)-based methodology widely used for the evaluation of microstructural integrity of the central nervous system (CNS), particularly of brain white matter fibers and bundles. Methods: The most common parameters evaluated in a DTI study are the fractional anisotropy (FA) and mean diffusivity (MD). Combining FA and MD analyses is commonly used in the evaluation of various types of brain pathologies, such as brain tumors, where a combined analysis allows an accurate tumor characterization. Results: Recent studies have shown that FA and MD could be of value in non-oncologic spinal pathology. In this regard, it has been …
Primary ciliary dyskinesia assessment by means of optical flow analysis of phase-contrast microscopy images
2014
Primary ciliary dyskinesia implies cilia with defective or total absence of motility, which may result in sinusitis, chronic bronchitis, bronchiectasis and male infertility. Diagnosis can be difficult and is based on an abnormal ciliary beat frequency (CBF) and beat pattern. In this paper, we present a method to determine CBF of isolated cells through the analysis of phase-contrast microscopy images, estimating cilia motion by means of an optical flow algorithm. After having analyzed 28 image sequences (14 with a normal beat pattern and 14 with a dyskinetic pattern), the normal group presented a CBF of 5.2 +/- 1.6 Hz, while the dyskinetic patients presented a 1.9 +/- 0.9 Hz CBF. The cutoff …
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…
Cardiovascular Imaging Techniques in Systemic Rheumatic Diseases
2018
The risk of cardiovascular (CV) events and mortality is significantly higher in patients with systemic rheumatic diseases than in the general population. Although CV involvement in such patients is highly heterogeneous and may affect various structures of the heart, it can now be diagnosed earlier and promptly treated. Various types of assessments are employed for the evaluation of CV risk such as transthoracic or transesophageal echocardiography, magnetic resonance imaging (MRI), and computed tomography (CT) to investigate valve abnormalities, pericardial disease, and ventricular wall motion defects. The diameter of coronary arteries can be assessed using invasive quantitative coronarograp…
Effect of Computer-Aided Navigation Techniques on the Accuracy of Endodontic Access Cavities: A Systematic Review and Meta-Analysis
2021
Simple Summary The endodontic access cavity is an essential step in the root canal treatment allowing the access and location of the root canal system. The inaccuracy during the endodontic access cavitie can lead to intraoperative complications such as missed root canals or root perforations, and hence affect the prognosis of the root canal treatment. The development of computer-aided static and dynamic navigation techniques has improved the accuracy of endodontic access cavities and root canal location; however, it is necessary a comparative analysis to clarify which of the computer-aided navigation system is more accurate. This systematic review and meta-analysis aims to clarify the root …
<title>Eye movements during silent and oral reading with stabilized versus free head movement and different eye-trackers</title>
2008
Eye movement research of reading has been done on a battery of eye-tracking setups during last decades. We compared reading data of the same group of six students, their eyes were tracked by a video-based helmet-mounted system with the data sampling frequency of 50 Hz and a setup with a chin-rest at 240 Hz. We found that not only the number of fixations may decrease after reading practice, but so does also the mean duration of fixations. In spite of the short duration of saccades, their distributions and changes in them are similarly reported in the two experimental conditions. Lack of significant correlation in the HED data testifies to the result variability due to measurement technique. …
The Effects of Melodic Grouping and Meter on Eye Movements during Simple Sight-Reading Tasks
2009
This study concerns the processes of eye movements during simple sight-reading tasks, concentrating on the processing of melodic groups separated by larger intervals and the effects of metrical placement of such groups. Thirty-two participants with varying musical background sight-read eight short melodies in two separate sessions. Eye movements during playing were recorded using an eye-tracker, and the performances on an electric piano with sequencer software. The melodies in question were of two types: melodic groupings were either aligned with the metrical divisions or made to overlap with them. The results indicate that reinspections to previously fixated notes during sight-reading incr…
A Dynamic Electrical Scheme for the optimal reconfiguration of PV modules under non-homogeneous solar irradiation
2012
This paper presents a strategy for the maximization of the output power of photovoltaic (PV) systems under non homogeneous solar irradiation by means of automatic reconfiguration of the PV arrays layout. The innovation of the proposed approach is the employment of a simple Dynamic Electrical Scheme (DES), allowing a large number of possible modules interconnection, to be installed between the PV generator and the inverter. The models of the PV generator and of the DES have been realized and simulated with Simulink (Dynamic System Simulation for MATLAB). The attained experimental results appear to be quite interesting in terms of the attainable benefit in power and thus energy terms. The lim…
Motility analysis by means of video tracked markers
2018
Abstract The motility of the gastrointestinal tract is crucial for digestive activity and dysfunction can lead to severe disease pattern. A method for analysing the motility is needed when treatment approaches shall be evaluated. Therefore markers attached to different locations on the stomach and the bowel of pigs are video tracked in this research study. The markers are designed to provide a high contrast and have an adhesive side for fixation. Above the operation field a video camera has been placed to film the markers during the procedure. To analyse the video data a special algorithm has been implemented. The algorithm requires a registration process at the beginning of each recording …
All Eyes on Me : Behaving as Soloist in Duo Performances Leads to Increased Body Movements and Attracts Observers’ Visual Attention
2020
Duo musicians exhibit a broad variety of bodily gestures, but it is unclear how soloists’ and accompanists’ movements differ and to what extent they attract observers’ visual attention. In Experiment 1, seven musical duos’ body movements were tracked while they performed two pieces in two different conditions. In a congruent condition, soloist and accompanist behaved according to their expected musical roles; in an incongruent condition, the soloist behaved as accompanist and vice versa. Results revealed that behaving as soloist, regardless of the condition, led to more, smoother, and faster head and shoulder movements over a larger area than behaving as accompanist. Moreover, accompanists …