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The purpose of this paper is to provide a scientific basis for a unified standard of the reference value of young people's erythrocyte sedimentation rate (ESR) in China. The reference values of healthy young people's ESR were collected according to the Wintrobe method, and the relationship between the reference value of young people's ESR and altitude was tested in this paper. It was found that the reference value of young people's ESR decreases when the altitude gradually increases, and the relationship is significant. The method of mathematical univariate regression analysis was used to deduce two regression equations: Y(1) = 10.92-0.00183X +/-2.59 and Y(2) = 18.58-0.00319X +/-4.37. If the altitude value of a particular area of China is known, the reference value of young people's ESR can be calculated by means of the regression equations. Furthermore, depending on the altitude, China can be divided into three districts: Qingzang, Central and Eastern districts. [ABSTRACT FROM AUTHOR]

Fluid-solid interaction is a primary feature of cardiovascular flows. There is increasing interest in the numerical solution of these systems as the extensive computational resource required for such studies becomes available. One form of coupling is an external weak coupling of separate solid and fluid mechanics codes. Information about the stress tensor and displacement vector at the wetted boundary is passed between the codes, and an iterative scheme is employed to move towards convergence of these parameters at each time step. This approach has the attraction that separate codes with the most extensive functionality for each of the separate phases can be selected, which might be important in the context of the complex rheology and contact mechanics that often feature in cardiovascular systems. Penrose and Staples describe a weak coupling of CFX for computational fluid mechanics to ANSYS for solid mechanics, based on a simple Jacobi iteration scheme. It is important to validate the coupled numerical solutions. An extensive analytical study of flow in elastic-walled tubes was carried out by Womersley in the late 1950s. This paper describes the performance of the coupling software for the straight elastic-walled tube, and compares the results with Womersley's analytical solutions. It also presents preliminary results demonstrating the application of the coupled software in the context of a stented vessel. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop an algorithm for prediction of exacerbation onset in Chronic Obstructive Pulmonary Disease (COPD) patients based on continuous self-monitoring of physiological parameters from telehome-care monitoring. 151 physiological parameters of COPD patients were monitored on a daily/weekly basis for up to 2 years. Data were segmented in 30-day periods leading up to an exacerbation (exacerbation episode) and starting from a 14-day recovery period post-exacerbation (control episode) and tested in 6 intervals to predict exacerbation onset using k-nearest neighbour (k = 1, 3, 5). A classifier with sensitivity of 73%, specificity of 74%, positive predictive value of 69%, negative predictive value of 78% and an accuracy of 74% was achieved using data intervals consisting of 5 days. Intelligent processing of physiological recordings have potential for predicting exacerbation onset. [ABSTRACT FROM PUBLISHER]

Four temporal and four spectral parameters of heart rate variability were compared after they were computed with two different time series generation methods: the RR intervals and the numerical values of heart rate provided by the Finapres. Recordings were obtained from 10 healthy subjects throughout five experimental conditions: supine, standing, controlled breathing, exercise and recovery. The mean and the RMS value of successive differences showed significant differences between the two methods. The spectral parameters were statistically different only during standing and exercise. The larger high frequency component and the lower HF/LF ratio by the Finapres method, observed during exercise, can be explained by the higher breathing influence on the peak-to-peak pressure intervals, in relation to RR intervals. Therefore, the high frequency component within mechanic intervals could possibly reflect the non-neural respiratory influence. In conclusion, values of heart rate provided by the Finapres are not completely interchangeable with those obtained from the ECG during the studied conditions. [ABSTRACT FROM AUTHOR]