Neurofeedback training (NFT) enables users to learn self-control of EEG activity of interest and then to create many benefits on cognitive function. A considerable number of nonresponders who fail to achieve successful NFT have often been reported in the within-session prediction. This study aimed to investigate successful EEG NFT of upregulation alpha activity in terms of trainability, independence, and between-session predictability validation.
View Article and Find Full Text PDFAs inflow and outflow stenoses worsen, both flow resistance and pressure increase in the stenotic vascular access. During dialysis, when blood flow decreases, it may retrograde from the peripheral artery through the palmar arch to the arterial anastomosis site. Arterial steal syndrome (ASS) causes distal hypoperfusion, resulting in hand ischemia or extremity pain and edema.
View Article and Find Full Text PDFObjective: Patients with cardiac arrhythmia were more likely to develop stroke than general population. The therapeutic effect of traditional Chinese medicine (TCM) on the risk of stroke in patients with cardiac arrhythmia was unknown. The aim of this study is to investigate the risk of stroke in patients with cardiac arrhythmia receiving TCM.
View Article and Find Full Text PDFThe biomechanical properties of soft tissues vary with pathological phenomenon. Ultrasound elasticity imaging is a noninvasive method used to analyze the local biomechanical properties of soft tissues in clinical diagnosis. However, the echo signal-to-noise ratio (eSNR) is diminished because of the attenuation of ultrasonic energy by soft tissues.
View Article and Find Full Text PDFBackground: Whether acupuncture protects stroke patients from acute myocardial infarction (AMI) has not been studied previously. The purpose of this study was to investigate the risk of AMI among stroke patients receiving acupuncture treatment.
Methods: Taiwan's National Health Insurance Research Database was used to conduct a retrospective cohort study of 23475 stroke patients aged 40-79 years receiving acupuncture treatment and 46950 propensity score-matched stroke patients not receiving acupuncture treatment who served as controls from 2000 to 2004.
This study proposes virtual-reality (VR) simulator system for double interventional cardiac catheterization (ICC) using fractional-order vascular access tracker and haptic force producer. An endoscope or a catheter for diagnosis and surgery of cardiovascular disease has been commonly used in minimally invasive surgery. It needs specific skills and experiences for young surgeons or postgraduate year (PGY) students to operate a Berman catheter and a pigtail catheter in the inside of the human body and requires avoiding damaging vessels.
View Article and Find Full Text PDFThis study proposes multiple-site hemodynamic analysis of Doppler ultrasound with an adaptive color relation classifier for arteriovenous access occlusion evaluation in routine examinations. The hemodynamic analysis is used to express the properties of blood flow through a vital access or a tube, using dimensionless numbers. An acoustic measurement is carried out to detect the peak-systolic and peak-diastolic velocities of blood flow from the arterial anastomosis sites (A) to the venous anastomosis sites (V).
View Article and Find Full Text PDFBackground: Weaning is typically regarded as a process of discontinuing mechanical ventilation in the daily practice of an intensive care unit (ICU). Among the ICU patients, 39%-40% need mechanical ventilator for sustaining their lives. The predictive rate of successful weaning achieved only 35-60% for decisions made by physicians.
View Article and Find Full Text PDFThis paper proposes a rule-based decision-making diagnosis system to evaluate arteriovenous shunt (AVS) stenosis for long-term hemodialysis treatment of patients using fuzzy petri nets (FPNs). AVS stenoses are often associated with blood sounds, resulting from turbulent flow over the narrowed blood vessel. Phonoangiography provides a noninvasive technique to monitor the sounds of the AVS.
View Article and Find Full Text PDFTo detect the early developmental stages of arteriovenous access (AVA) stenosis in hemodialysis patients, this study explored a stenosis detector based on the Burg method and the fractional-order chaos system (FOCS). The bruit developed by the blood flowing through AVA can be a viable noninvasive strategy for monitoring AVA functions. We used the Burg method of the autoregressive model to estimate the frequency spectra of phonographic signals recorded by an electronic stethoscope in patients' AVAs and to identify the spectral peaks in the region of 25-800 Hz.
View Article and Find Full Text PDFThe authors applied independent component analysis to oscillations of heart rate and blood pressure and obtained a new index of sympathovagal balance. The performance of this index was tested in patients with carotid artery stenting and in the EuroBavar data set according to the following criteria: (1) the index should vary similarly among subjects in response to different autonomic conditions; (2) the variability in the index among subjects exposed to the same autonomic conditions should be small; and (3) the response of the index to various autonomic conditions should reflect the underlying changes in the physiological state and have a meaningful interpretation. The new index from independent component analysis better fulfilled the criteria than the commonly used sympathovagal index, the ratio of low-to-high frequency spectra power of heart rate variability, and had higher discrimination power in distinguishing the autonomic status of the patients who had undergone carotid artery stenting from that of the control subjects.
View Article and Find Full Text PDFIn Taiwan, the number of the patients needing dialysis increases rapidly in recent years. Because there is risk in every hemodialysis session, monitoring physiological status, such as blood pressure measurement every 30 min to 1 h is needed during about 4 h hemodialysis process. Therefore, an assisted measurement on blood pressure is needful in dialysis care centers.
View Article and Find Full Text PDFBaroreflex sensitivity is recognized for its prognostic relevance to cardio-vascular and cerebro-vascular risks. However, little is known about the long-term outcome of baroreflex function in patients with carotid stenosis undergoing carotid stenting. Heart rate variability and cardio-vascular autonomic function, including baroreflex sensitivity, were examined using non-invasive methods in 22 adult patients who underwent carotid stenting.
View Article and Find Full Text PDFA method was presented that employs standard linac QA tools to verify the accuracy of film reconstruction algorithms used in the brachytherapy planning system. Verification of reconstruction techniques is important as suggested in the ESTRO booklet 8: "The institution should verify the full process of any reconstruction technique employed clinically." Error modeling was also performed to analyze seed-position errors.
View Article and Find Full Text PDFPurpose: This study sought to quantify divergence eye movements and differences between divergence and convergence to smoothly moving ramp, step, and disappearing step stimuli.
Methods: Eight visually normal, adult subjects participated in three experiments investigating the dynamics of responses using an infrared limbal eye tracker.
Results: There were four primary findings: (1) a smooth tracking behavior was observed for slow ramps while the fast ramps elicited smooth tracking combined with a high-velocity, step-like behavior; (2) the high-velocity components observed in the faster ramps had a similar main sequence as divergence steps; (3) divergence dynamics to disappearing steps starting at the subject's near dissociated phoria level were similar to corresponding step responses; and (4) the high-velocity components from divergence ramps were dependent on initial vergence position, whereas the high-velocity components from convergence ramps were not.
We propose a new method based on statistical analysis technique to determine the minimum setup distance of a well chamber used in the calibration of 192Ir high dose rate (HDR). The chamber should be placed at least this distance away from any wall or from the floor in order to mitigate the effect of scatter. Three different chambers were included in this study, namely, Sun Nuclear Corporation, Nucletron, and Standard Imaging.
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
March 2008
Tissue injury and its ensuing healing process cause scar formation. In addition to physical disability, the subsequent disfigurements from burns often bring negative psychological impacts on the survivors. Scar hypertrophy and contracture limit the joint motion and body function of the patient.
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
March 2008
This paper proposes a method for multiple ECG beats recognition using novel grey relational analysis (GRA). Converts each QRS complex to a Fourier spectrum from ECG signals, the spectrum varies with the rhythm origin and conduction path. The variations of power spectra are observed in the range of 0 Hz-20 Hz in the frequency domain.
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
September 2008
Recently, the quantitative ultrasound (QUS) technique has been widely applied for the characterization of tissues. For example, it can be used for the quantization of Achilles tendons based on the broadband ultrasound attenuation (BUA) and speed of sound (SOS) when the ultrasound wave passes through the tissues. The main purpose of this study is to develop an integrated system to investigate the correlations between the measurements of Achilles tendons using QUS (UBIS 5000) and 2D ultrasound instrument (HDI 5000).
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
September 2008
This paper proposes a method for electrocardiogram (ECG) heartbeat pattern recognition using adaptive wavelet network (AWN). The ECG beat recognition can be divided into a sequence of stages, starting from feature extraction and conversion of QRS complexes, and then identifying cardiac arrhythmias based on the detected features. The discrimination method of ECG beats is a two-subnetwork architecture, consisting of a wavelet layer and a probabilistic neural network (PNN).
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
October 2012
The relationship between the product of peak velocity and duration (VD) and saccadic amplitude is tightly correlated. The velocity profile of a saccade was referred as a triangular profile; whereas the saccadic amplitude is proportional to VD. From our observation and derivation, in addition to the triangular profile, the rational power function can also be applied to explain the linear relationship between the saccadic amplitude and VD.
View Article and Find Full Text PDFWe introduce an empirical formula to directly calculate the room scatter factor in the calibration of (192)Ir HDR using a Farmer chamber. Compared to the data of Selvam et al (2001 Phys. Med.
View Article and Find Full Text PDFThe speed of sound (SOS) has become a useful tool in osteoporosis assessment, since it represents a combination of density and compressibility of bone tissue and should provide better information on bone quality and an estimate the fracture risk. In general, the speed of sound on dispersive material, such as bone tissue, depends strongly on frequency. Therefore, a measurement of velocity dispersion magnitude (VDM) might provide more important bone structure information than measurements of bone mineral density (BMD), SOS or broadband ultrasound attenuation (BUA).
View Article and Find Full Text PDFBone mineral density (BMD) is used as a clinical estimate of the risk of fracture. Ultrasound provides an alternative or complement to X-ray based methods of bone densitometry for determining BMD. Among ultrasonic characteristics, the speed of sound (SOS) is a useful tool for assessment of osteoporosis because, as recently reported, it represents a combination of density and compressibility of bone tissue.
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