The non-stationary interference with the analysis parameters of short-term heart rate variability (HRV) has been studied. The results show that although all considered parameters fluctuate with the lapse of time, only HFnorm and sample entropy (SE) correlate significantly with non-stationary interference. Therefore, the low frequency fluctuations of HRV contain not only the non-stationary interference, but also the intrinsic cardiac dynamic characteristics. Specially, the results of the base-scale entropy (BE) analysis of three groups of people, and of three kinds of noises are contrasted. It is shown that, at the expense of outstanding anti-nonstationarity, BE fails to depict the long range correlation of HRV.
Algorithms ; Autonomic Nervous System ; physiology ; Electrocardiography ; methods ; Entropy ; Heart Rate ; physiology ; Humans ; Signal Processing, Computer-Assisted

Objective:To analyze the clinical parameters of the patients with femoral neck fracture such as general condition,therapy method,hospitalized expense so as to provide more effective management plan for the clinical work.Methods:The patients with femoral neck fracture above 50 years who received in-patient treatment from 2008 January to 2012 December were admitted into this study.We collected and analyzed the information,such as age,chronic medical disease,therapy method,hospitalized duration and expense and so on.Results:There were 1 794 femoral neck fracture patients above 50 years (male/female=1/2.06)in our hospital in recent 5 years and the annual average rate of increase was 7.3%. The average age of the patients was (69.9 ±10.7)years and the annual average rate of increase was 0.6%.The chronic medical disease diagnosis ratio was 55.0%.The average waiting time for operation was (6.8 ±4.2)days and the average hospitalized duration was (12.9 ±4.9)days which showed down-ward trend in recent years. The most popular operations were cannulated screw internal fixation (41.8%)and artificial femoral head replacement (34.1%).In the study,146 cases (7.9%)received nonsurgical treatment which showed downward trend.The average hospitalized expense was (35 075 .7 ± 1 1 343.2)yuan which showed no obvious change in recent years.The cost for the females was more than that for the males.The expense for hemiarthroplasty and total hip arthroplasty increased while that for cannulated screw internal fixation decreased gradually.Conclusion:The cannulated screw internal fixa-tion and artificial femoral head replacement were the most important operations for the patients with femo-ral neck fracture.The number and the average age of the patients were on the rise while the expense showed no obvious change in recent years.

The dynamic changes of synchronous 12-lead ECG signal's correlation dimension (D2) of an anesthetized rabbit were investigated primarily under three different pathologic conditions. The results showed that the D2 derived from different lead signals was not a constant whether the rabbit was in normal state or in emergent myocardial infarction condition, it demonstrated distribution characteristic. Compared with the same lead signal, D2 of limb lead almost kept constant, D2 of chest lead got higher when the sphere of emergent ischemia extended larger. D2 showed the potential application in the diagnosis of coronary heart disease.
Animals ; Electrocardiography ; Myocardial Infarction ; physiopathology ; Nonlinear Dynamics ; Rabbits ; Signal Processing, Computer-Assisted

Image mosaicing can solve the problem that only very limited field of view is available when highly magnifying lens is used in microscope imaging. This paper puts forward an equation of the system's influence to the grayscale distribution of the medical microscopic images, based on the analysis of the influence. Then, by the system equation and the accurate registration equation, the least-squares optimization error function can be formulated. By these equations, a set of transcendental equations is formed. We can estimate the system's influence on the gray-level of the images by singular-value decomposition (SVD), based on the equations set, and compensating for it. This permits image mosaicing seamlessly, without lowering the speed.
Humans ; Image Enhancement ; methods ; Image Processing, Computer-Assisted ; methods ; Microscopy ; methods

In this paper is reported a method using joint entropy to analyze the nonlinear dynamical complexity of short-term heart rate variability(HRV) signal. This method can effectively pick up dynamical information from the short-term heartbeat time series, reflect the dynamical complexity of heart rate variability, and so improve the quality of being covenient in clinical application. At first, the joint entropy method is demonstrated by applying it to the low-dimensional nonlinear deterministic systems such as logistic map and henon map. Then, the proposition is applied to the short-term heartbeat time series. The result shows that the method could robustly discriminate the patterns generated from healthy and pathologic states, as well as aging. Furthermore, the authors point out that decreased nonlinear dynamical complexity in the heartbeat time series with physiological aging and pathologic states is probably due to self-adjusting ability depression with aging and disease. At last, using the joint entropy method,the authors uncover nonrandom patterns in the ventricular response to atrial fibrillation.
Adult ; Aged ; Electrocardiography ; methods ; Entropy ; Heart Rate ; physiology ; Humans ; Middle Aged ; Nonlinear Dynamics ; Signal Processing, Computer-Assisted ; Ventricular Fibrillation ; physiopathology ; Young Adult

Neural networks can fit any nonlinear function. After drawing out several characteristic parameters from the three-dimension spectrum for high frequency QRS waves, we input them into the network and trained the network. In this way, we can get a m-dimension curved surface in the m-dimension space which is constructed by those parameters, and this curved surface divides the space into two parts: the unhealthiness and the health. Now, the network can automatically distinguish between the healthiness and the unhealthiness according to their three-dimension spectrum for high frequency QRS waves.
Algorithms ; Coronary Disease ; diagnosis ; Electrocardiography ; Humans ; Image Processing, Computer-Assisted ; Neural Networks (Computer)

We analyzed the multifractal singularity spectrum of synchronous 12-lead ECG (electrocardiogram) signals from heart and brain disease patients, and found that multifractal curves of different leads do not overlap each other. After calculating the scope of the singularity strength, we noticed that the averages of scope are not the same in different subjects,and the dispersing degree is also different in someone's different leads. Both the deltaalpha, the average of the deltaalpha, and the dispersing degree deltaalpha (be defined as standard deviation) of the deltaalpha of every one's 12-lead ECG were computed. Then, a comparison was made between the spectrum of the healthy subjects and the heart disease patients. The results showed that their deltaalpha are close, but their deltaalpha are markedly different. Also the healthy subjects and brain disease patients were compared, we found that their deltaalpha are close, but their deltaalpha are markedly different. These indicate that the character of multifractal spectrum is controlled by both the neurosystem of body and the self-syntonic property of cardiac structures. Furthermore, the deltaalpha is related with the neuroautonomic control of people's body on the ECG, and the deltaalpha is related with the anisotropy of the heterogeneous tissue and the electric signal propagation in heart.
Aged ; Brain Concussion ; physiopathology ; Coronary Disease ; physiopathology ; Electrocardiography ; methods ; Humans ; Signal Processing, Computer-Assisted

By analyzing the electrocardiosignals, many scholars have found remarkable and outstanding dynamic characteristics in both normal hearts and sick hearts. Based on those findings, a model of acute myocardial ischemia of six rabbits is designed by us and is presented here. The electrocardiogram (ECG) signals of different time series are calculated, and the figures of correlation dimensions-time and the maximum Lyapunov exponents-time are given. The results show that the existence of myocardial ischemia will bring the decline of the value of maximum Lyapunov exponents and correlation dimensions, after the figures being analyzed with electrophysiological and anatomical knowledge. The maximum Lyapunov exponents of ECG demonstrate the chaotic quality of the system and the correlation dimension of ECG demonstrates the complexity of the system, and there is no explicit relation between them. Correlation dimensions of ECG signals might be more influenced by partial heart system, compared with the maximum Lyapunov exponents of ECG signals.
Animals ; Electrocardiography ; Heart Rate ; physiology ; Models, Biological ; Models, Cardiovascular ; Myocardial Ischemia ; physiopathology ; Nonlinear Dynamics ; Rabbits ; Signal Processing, Computer-Assisted

From November to December of 2018, twenty 65-year-old or older women patients with knee osteoarthritis were recruited from the Department of Physical Therapy, the First Affiliated Hospital of Anhui Medical University. Meanwhile, twenty healthy 65-year-old or older women were recruited from the local community. The results showed that the knee contact angle of the patient group was more flexed ( P=0.040), and the minimum angle of the knee joint increased ( P=0.008) during the stance period compared to the healthy group. However, there was no significant difference in the maximum contact angle between the angle of hip and ankle joints. In addition, the tibialis anterior muscle of the patients was significantly smaller than the healthy group ( P=0.023). Therefore, knee osteoarthritis could change the gait and muscle activity of older women, especially the knee joint.

From November to December of 2018, twenty 65-year-old or older women patients with knee osteoarthritis were recruited from the Department of Physical Therapy, the First Affiliated Hospital of Anhui Medical University. Meanwhile, twenty healthy 65-year-old or older women were recruited from the local community. The results showed that the knee contact angle of the patient group was more flexed ( P=0.040), and the minimum angle of the knee joint increased ( P=0.008) during the stance period compared to the healthy group. However, there was no significant difference in the maximum contact angle between the angle of hip and ankle joints. In addition, the tibialis anterior muscle of the patients was significantly smaller than the healthy group ( P=0.023). Therefore, knee osteoarthritis could change the gait and muscle activity of older women, especially the knee joint.