European Journal of Obstetrics & Gynecology and Reproductive Biology, 2009
In physiological research, there are not too many studies on multivariate data sets, containing t... more In physiological research, there are not too many studies on multivariate data sets, containing two or more simultaneously recorded time series. It is important to examine synchronization in these kinds of signals. The aim of this study is to present the linear measures: the cross-correlation function, the coherence function, the wavelet cross-correlation and the wavelet coherence to assess synchronization between contractions in different topographic regions of the uterus. Spontaneous uterine activity was recorded directly by a dual micro-tip catheter (Millar Instruments, Inc., USA). The device consisted of two ultra-miniature pressure sensors. One sensor was placed in the fundus, the other one in the cervix. For this analysis, a healthy patient with normal contractions, a patient with dysmenorrhea, a patient with fibromyomas in the follicular phase, and the patient with endometriosis were selected. For each method the values of synchronization parameters for normal contractions were higher than the values of these parameters for other pairs of signals. The differences between these four groups of the uterine contraction signals were clear. The lowest values of the synchronization measures were in the case of dysmenorrheic patient. The analysis of synchronization of the uterine contractions signals may have a diagnostic value. For intrauterine pressure signals results obtained by means of different synchronization methods are different, but consistent.
V Symposium on Medical Physics (III International Symposium on Medical Physics), Ustroń, Poland, ... more V Symposium on Medical Physics (III International Symposium on Medical Physics), Ustroń, Poland, September 20-23, 2006
European Journal of Obstetrics & Gynecology and Reproductive Biology, 2009
In physiological research, there are not too many studies on multivariate data sets, containing t... more In physiological research, there are not too many studies on multivariate data sets, containing two or more simultaneously recorded time series. It is important to examine synchronization in these kinds of signals. The aim of this study is to present the linear measures: the cross-correlation function, the coherence function, the wavelet cross-correlation and the wavelet coherence to assess synchronization between contractions in different topographic regions of the uterus. Spontaneous uterine activity was recorded directly by a dual micro-tip catheter (Millar Instruments, Inc., USA). The device consisted of two ultra-miniature pressure sensors. One sensor was placed in the fundus, the other one in the cervix. For this analysis, a healthy patient with normal contractions, a patient with dysmenorrhea, a patient with fibromyomas in the follicular phase, and the patient with endometriosis were selected. For each method the values of synchronization parameters for normal contractions were higher than the values of these parameters for other pairs of signals. The differences between these four groups of the uterine contraction signals were clear. The lowest values of the synchronization measures were in the case of dysmenorrheic patient. The analysis of synchronization of the uterine contractions signals may have a diagnostic value. For intrauterine pressure signals results obtained by means of different synchronization methods are different, but consistent.
It was shown earlier that nonlinear processes probably generate uterine contractions. In this stu... more It was shown earlier that nonlinear processes probably generate uterine contractions. In this study, the nonlinear synchronization measures (the mutual correlation dimension, the cross-approximate entropy, the mutual information and the nonlinear interdependencies) were employed to analyze the association between two time series representing the uterine contraction activity. Here the notion of synchronization is used in a loose sense as the synonym of correlation, the similarity of the signals or the similarity of their dynamics. The signals were recorded from the different topographic regions of the uterus: the cervix and the fundus. The results obtained by means of different algorithms are different but qualitatively similar for the checked methods.
The irregularity or ”roughness” of medical images is quantified by means of fractal dimension D. ... more The irregularity or ”roughness” of medical images is quantified by means of fractal dimension D. For medical images diagnostically important information often lies in the texture. In this paper we describe the application of the intensity difference scaling method for assessment of the fractal dimension D in the irregular regions of interest (irregular ROI-s). Near boundary between different tissues or structures the values of fractal dimensions changed significantly. It is difficult to fit entire regular region of interest within the examined organ with simultaneous inclusion of the relevant fragment, and at the same time to avoid the influence of boundaries.
Analysis of the uterine contractility in non-pregnant women provides information about physiologi... more Analysis of the uterine contractility in non-pregnant women provides information about physiological changes during menstrual cycle. Spontaneous uterine activity was recorded directly by a micro-tip catheter (Millar Instruments, Inc. USA). The sensor produced an electrical signal, which varied in direct proportion to the magnitude of measured pressure. The study was approved by the regional ethics committee. We used the techniques of surrogate data analysis to testing for nonlinearity in the uterine contraction signals. Approximate entropy was the test statistic. For this analysis a healthy patient with normal contractions, a patient with dysmenorrhea and a patient with fibromyomas in the follicular phase were selected. The results showed that the spontaneous uterine contractions are considered to contain nonlinear features.
The aim of this study is to evaluate the synchronization of signals between different areas of th... more The aim of this study is to evaluate the synchronization of signals between different areas of the brain using nonlinear methods: the mutual correlation dimension, the cross approximate entropy, the mutual information function, and the nonlinear interdependencies S, H, and N. As the reference method, the linear cross-correlation function was used. The EEG signals were referenced to the electrodes placed at the ear lobes. We analyzed the signals representing the bioelectric activity of the brain obtained in studies of patients suffering from epilepsy and control group. The results obtained by means of different synchronization measures indicate that the signals from the control group are more synchronized than the signals collected from the people suffering from epilepsy. The source of epileptic discharge is located in the occipital part, the left side of the brain and this is where the greatest similarity between the signals is observed. The nonlinear measures of synchronization may be useful as diagnostic parameters.
For medical images diagnostically important information often lies in the texture. Fractal dimens... more For medical images diagnostically important information often lies in the texture. Fractal dimension may be used as an index of irregularity. In this paper we describe the adaptation of the intensity difference scaling method for assessment of the fractal dimension D in the irregular regions of interest (irregular ROIs). This is of great importance because the investigated regions are often small. It is difficult to fit entire regular region of interest within the examined organ with simultaneous inclusion of the relevant fragment, and at the same time to avoid the influence of boundaries. Fractal analysis of various kinds of medical images: panoramic radiography and nuclear medicine scan showed the validity of assessment of D in irregular ROIs.
European Journal of Obstetrics & Gynecology and Reproductive Biology, 2009
In physiological research, there are not too many studies on multivariate data sets, containing t... more In physiological research, there are not too many studies on multivariate data sets, containing two or more simultaneously recorded time series. It is important to examine synchronization in these kinds of signals. The aim of this study is to present the linear measures: the cross-correlation function, the coherence function, the wavelet cross-correlation and the wavelet coherence to assess synchronization between contractions in different topographic regions of the uterus. Spontaneous uterine activity was recorded directly by a dual micro-tip catheter (Millar Instruments, Inc., USA). The device consisted of two ultra-miniature pressure sensors. One sensor was placed in the fundus, the other one in the cervix. For this analysis, a healthy patient with normal contractions, a patient with dysmenorrhea, a patient with fibromyomas in the follicular phase, and the patient with endometriosis were selected. For each method the values of synchronization parameters for normal contractions were higher than the values of these parameters for other pairs of signals. The differences between these four groups of the uterine contraction signals were clear. The lowest values of the synchronization measures were in the case of dysmenorrheic patient. The analysis of synchronization of the uterine contractions signals may have a diagnostic value. For intrauterine pressure signals results obtained by means of different synchronization methods are different, but consistent.
V Symposium on Medical Physics (III International Symposium on Medical Physics), Ustroń, Poland, ... more V Symposium on Medical Physics (III International Symposium on Medical Physics), Ustroń, Poland, September 20-23, 2006
European Journal of Obstetrics & Gynecology and Reproductive Biology, 2009
In physiological research, there are not too many studies on multivariate data sets, containing t... more In physiological research, there are not too many studies on multivariate data sets, containing two or more simultaneously recorded time series. It is important to examine synchronization in these kinds of signals. The aim of this study is to present the linear measures: the cross-correlation function, the coherence function, the wavelet cross-correlation and the wavelet coherence to assess synchronization between contractions in different topographic regions of the uterus. Spontaneous uterine activity was recorded directly by a dual micro-tip catheter (Millar Instruments, Inc., USA). The device consisted of two ultra-miniature pressure sensors. One sensor was placed in the fundus, the other one in the cervix. For this analysis, a healthy patient with normal contractions, a patient with dysmenorrhea, a patient with fibromyomas in the follicular phase, and the patient with endometriosis were selected. For each method the values of synchronization parameters for normal contractions were higher than the values of these parameters for other pairs of signals. The differences between these four groups of the uterine contraction signals were clear. The lowest values of the synchronization measures were in the case of dysmenorrheic patient. The analysis of synchronization of the uterine contractions signals may have a diagnostic value. For intrauterine pressure signals results obtained by means of different synchronization methods are different, but consistent.
It was shown earlier that nonlinear processes probably generate uterine contractions. In this stu... more It was shown earlier that nonlinear processes probably generate uterine contractions. In this study, the nonlinear synchronization measures (the mutual correlation dimension, the cross-approximate entropy, the mutual information and the nonlinear interdependencies) were employed to analyze the association between two time series representing the uterine contraction activity. Here the notion of synchronization is used in a loose sense as the synonym of correlation, the similarity of the signals or the similarity of their dynamics. The signals were recorded from the different topographic regions of the uterus: the cervix and the fundus. The results obtained by means of different algorithms are different but qualitatively similar for the checked methods.
The irregularity or ”roughness” of medical images is quantified by means of fractal dimension D. ... more The irregularity or ”roughness” of medical images is quantified by means of fractal dimension D. For medical images diagnostically important information often lies in the texture. In this paper we describe the application of the intensity difference scaling method for assessment of the fractal dimension D in the irregular regions of interest (irregular ROI-s). Near boundary between different tissues or structures the values of fractal dimensions changed significantly. It is difficult to fit entire regular region of interest within the examined organ with simultaneous inclusion of the relevant fragment, and at the same time to avoid the influence of boundaries.
Analysis of the uterine contractility in non-pregnant women provides information about physiologi... more Analysis of the uterine contractility in non-pregnant women provides information about physiological changes during menstrual cycle. Spontaneous uterine activity was recorded directly by a micro-tip catheter (Millar Instruments, Inc. USA). The sensor produced an electrical signal, which varied in direct proportion to the magnitude of measured pressure. The study was approved by the regional ethics committee. We used the techniques of surrogate data analysis to testing for nonlinearity in the uterine contraction signals. Approximate entropy was the test statistic. For this analysis a healthy patient with normal contractions, a patient with dysmenorrhea and a patient with fibromyomas in the follicular phase were selected. The results showed that the spontaneous uterine contractions are considered to contain nonlinear features.
The aim of this study is to evaluate the synchronization of signals between different areas of th... more The aim of this study is to evaluate the synchronization of signals between different areas of the brain using nonlinear methods: the mutual correlation dimension, the cross approximate entropy, the mutual information function, and the nonlinear interdependencies S, H, and N. As the reference method, the linear cross-correlation function was used. The EEG signals were referenced to the electrodes placed at the ear lobes. We analyzed the signals representing the bioelectric activity of the brain obtained in studies of patients suffering from epilepsy and control group. The results obtained by means of different synchronization measures indicate that the signals from the control group are more synchronized than the signals collected from the people suffering from epilepsy. The source of epileptic discharge is located in the occipital part, the left side of the brain and this is where the greatest similarity between the signals is observed. The nonlinear measures of synchronization may be useful as diagnostic parameters.
For medical images diagnostically important information often lies in the texture. Fractal dimens... more For medical images diagnostically important information often lies in the texture. Fractal dimension may be used as an index of irregularity. In this paper we describe the adaptation of the intensity difference scaling method for assessment of the fractal dimension D in the irregular regions of interest (irregular ROIs). This is of great importance because the investigated regions are often small. It is difficult to fit entire regular region of interest within the examined organ with simultaneous inclusion of the relevant fragment, and at the same time to avoid the influence of boundaries. Fractal analysis of various kinds of medical images: panoramic radiography and nuclear medicine scan showed the validity of assessment of D in irregular ROIs.
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Papers by Marta Borowska