Muhammad Muinul Islam

Mental states estimation with the variation of physiological signals

In this paper, we describe the consequences of mental conditions due to the variation of electrocardiogram, electroencephalogram and blood pressure using BIOPAC system. The different data sets are collected using BIOPAC system in which subjects were induced to undergo the specific sequence of mental condition or cognitive state. For getting physiological signals during different affective condition, we utilized power point slide show, video clips and question-answer method which elicit mental reactions from the subjects. Data was taken before and after four tasks that encompassed the Motor Action (MA), Thought (TH), Memory Related (MR), Emotion (EM). These measured values were analyzed using BIOPAC AcqKnowledge software. It was found that the effect of motor action and thought states are mainly on blood pressure while memory related and emotion state mainly affect the ECG measurement. The EEG mainly detects the signal of task performed by the specific brain region where the electrodes are placed. Here the electrodes are placed in occipital lobe region which gives mainly the variation in alpha amplitude of EEG with eyes closed and eyes opened. Alpha wave amplitudes vary with the subjects attention to mental tasks performed with eyes closed.

CLG Optical Flow Approach and Frequency Analysis of Cranial Ultrasonogram Image Sequences

The artery pulsation has a strong correlation with the blood flow in the newborn baby head and tissuemotion has a relationship with artery pulsation. In this paper, we propose a novel method to estimate the tissuemotion quantitatively by combining local and global motion estimation methods, namely combined local-global (CLG) optical flow technique in cranial ultrasonogram of newborn babies. Tissue motions are estimated in different coronal sections successfully and their errors are also estimated. Further, we analyze the time variant tissue-motion by using discrete Fourier transform. We also observed the pulsation in the time variant motion images and strong pulsation is observed in the harmonic frequency of tissue-motion that has a relation to the heartbeat frequency of a newborn baby which is helpful for pediatric diagnosis.

Estimation of arterial input by a noninvasive image derived method in brain H2 15O PET study: confirmation of arterial location using MR angiography

A noninvasive method to estimate input function directly from H215O brain PET data for measurement of cerebral blood flow (CBF) was proposed in this study. The image derived input function (IDIF) method extracted the time-activity curves (TAC) of the major cerebral arteries at the skull base from the dynamic PET data. The extracted primordial IDIF showed almost the same radioactivity as the arterial input function (AIF) from sampled blood at the plateau part in the later phase, but significantly lower radioactivity in the initial arterial phase compared with that of AIF-TAC. To correct the initial part of the IDIF, a dispersion function was applied and two constants for the correction were determined by fitting with the individual AIF in 15 patients with unilateral arterial stenoocclusive lesions. The area under the curves (AUC) from the two input functions showed good agreement with the mean AUCIDIF/AUCAIF ratio of 0.92  ±  0.09. The final products of CBF and arterial-to-capillary vascular volume (V 0) obtained from the IDIF and AIF showed no difference, and had with high correlation coefficients.A noninvasive method to estimate input function directly from H215O brain PET data for measurement of cerebral blood flow (CBF) was proposed in this study. The image derived input function (IDIF) method extracted the time-activity curves (TAC) of the major cerebral arteries at the skull base from the dynamic PET data. The extracted primordial IDIF showed almost the same radioactivity as the arterial input function (AIF) from sampled blood at the plateau part in the later phase, but significantly lower radioactivity in the initial arterial phase compared with that of AIF-TAC. To correct the initial part of the IDIF, a dispersion function was applied and two constants for the correction were determined by fitting with the individual AIF in 15 patients with unilateral arterial stenoocclusive lesions. The area under the curves (AUC) from the two input functions showed good agreement with the mean AUCIDIF/ AUCAIF ratio of 0.92 ± 0.09. The final products of CBF and arterial-to-capillary vascular volume (V0) obtained from the IDIF and AIF showed no difference, and had with high correlation coefficients.

Determination of the Effect of Having Energy Drinks by Analyzing Blood Perfusion Signal

In this work, we evaluate the effect of having energy drinks using a laser Doppler Flowmetry technique by analyzing the blood perfusion signal before and after having energy drinks on healthy human subjects. After having energy drinks, it is observed that the amplitude of blood perfusion signal increases. Further analyzing the blood perfusion signal we have tried to determine the effect of having energy drinks on human subjects. The oscillations extended over a wide frequency scale and their periods varied in time. Within the frequency range studied, 0.0095–1.6 Hz, five characteristic oscillations were revealed, arising from both local and central regulatory mechanisms, e.g. endothelial/metabolic activity, sympathetic nerve activity, vascular myogenic activity, respiratory activity, and heart activity. We observed a significant change in metabolic and sympathetic nerve activity after having energy drinks. The frequency component relating metabolic and sympathetic nerve activity increase around 300% and 140% respectively. It is also observed a moderate change in myogenic and heart activity as the relative and absolute amplitude of the oscillations of this frequency interval increased around 80% and very little or all most no change in respiratory activity in response to having energy drinks.

Determination of the effect of having energy drinks using laser Doppler flowmetry

In the present study, we evaluated the effect of having energy drinks using laser Doppler flowmetry technique by determining blood flow changes after having energy drinks on healthy human subjects. After having energy drinks, it is observed that the amplitude of blood perfusion signal increases. Further we have analyzed frequency response of blood perfusion signal using windowed Fast Fourier Transform. The oscillations extended over a wide frequency scale and their periods varied in time. Within the frequency range studied, 0.0095-1.6 Hz, five characteristic oscillations were revealed, arising from both local and central regulatory mechanisms e.g. endothelial/metabolic activity, sympathetic nerve activity, vascular myogenic activity, respiratory activity, and heart activity. We observed a significant change in metabolic and sympathetic nerve activity after having energy drinks. The frequency component relating metabolic and sympathetic nerve activity increase around 300% and 140% respectively. It is also observed a moderate change in myogenic and heart activity as the relative and absolute amplitude of the oscillations of this frequency interval increased around 80% in response to having energy drinks.

Analyzing the effect of having energy drinks on metabolic, sympathetic and myogenic function by wavelet transforms using laser Doppler Flowmetry

The wavelet transform technique, a time-frequency method with logarithmic frequency resolution, was used to analyze the effect of having energy drinks (ED) using laser Doppler Flowmetry technique LDF100C (Biopac systems Inc.) by determining physiological activities after having energy drinks on 12 healthy human subjects. Traditional Fourier analysis does not provide sufficient resolution to reveal characteristic low frequencies. For this, time frequency analysis was performed. After having energy drinks, it is observed that the amplitude of blood perfusion signal increases around two fold. The physiological activities which include five different frequency intervals (FI) of total spectrum (0.0095-1.6 Hz), each of them related to endothelial or metabolic (0.0095-0.02 Hz), sympathetic or neurogenic (0.02-0.06 Hz), myogenic (0.06-0.15 Hz), respiratory (0.15-0.4 Hz) and cardiac or heart (0.4-1.6 Hz) activity, was also measured in BPU2/Hz before and after having energy drinks by further analyzing frequency spectrum of the blood perfusion signal using Discrete Wavelet transform. We observed a significant change in these activities after having energy drinks. The amplitude of frequency spectrum of LDF signal related to metabolic and sympathetic activity increase around five fold. A little change is observed in myogenic function which increases around three fold.

Neonatal brain pulsation strength analysis using wavelet transform

Ultrasonogram plays an important role for medical diagnosis because its convenience, easy to use, low cost in compared with other medical modalities. Ultrasound image analysis is mainly used in real-time but sometimes offline data is used for future diagnosis. In this paper, we analyze the artery pulsation caused by blood flow in neonatal brain using discrete wavelet transform. We quantitatively analyze and visualize the strength of artery pulsation from ultrasound image sequence in brightness mode for future diagnosis. From the pulsation amplitude visualization, the variation of the pulsation strength in different regions of the ultrasound image can be achieved. In our method, we directly use the pixel information of normal and asphyxiated neonates.

Analysis and visualization of pulsation in B-mode cranial ultrasound images

Cranial ultrasound scans are very essential part of the routine investigation of neonatal intensive care. The scan ultrasound image sequence are not only used for real-time diagnosis but also recorded for future diagnosis. In this paper, we analyze and visualize the pulsation amplitude caused by artery pulsation of blood flows from a video stream of ultrasound image sequence by using 1D fast Fourier transform in brightness mode for future diagnosis. The analysis has the advantages of observing pulsation amplitude which may strongly contribute paediatricians in diagnosis of newborn babys ischemic diseases. In our method, we analyze and visualize the pulsation of a typical coronal and a sagittal section of normal and asphyxiated neonates.