ObjectiveTo evaluate the effect of rural alone-two-child policy (RAC policy) on zero population growth, high sex ratio at birth (SRB), and aging population in China. MethodsRural areas of cities which implement the RAC policy were included. Data from the fifth and the sixth population censes were used to analyze the variation of the total fertility rate (TFR), SRB, and the number of teenagers of every household (NTH) in context of different social and economic levels. ResultsThe implementation of RAC policy in rural areas with middle and upper social economic levels showed a long-term effect of increasing the TFR and decreasing the SRB. The implementation of rural girl policy mixed with RAC policy in areas with middle social economic level showed a long-term effect of decreasing the TFR and increasing the SRB; but the long-term effect in areas with low social economic level was uncertain. The NTHs were decreased in all included areas. According to the urban and rural birth preference, we made inferences that the implementation of alone-two-child policy in cities could result in the increase of TFR and the decrease of SRB. ConclusionThe long-term effect of RAC policy implemented in rural areas with middle social economic level could solve the problems of zero population growth and the high SRB, but the long-term effect of mixed policy implemented in rural areas with middle social economic level may aggravate the two problems above. The RAC policy cannot solve the aging population problem in rural area.
The real-time monitoring of cerebral hemorrhage can reduce its disability and fatality rates greatly. On the basis of magnetic induction phase shift, we in this study used filter and amplifier hardware module, NI-PXI data-acquisition system and LabVIEW software to set up an experiment system. We used Band-pass sample method and correlation phase demodulation algorithm in the system. In order to test and evaluate the performance of the system, we carried out saline simulation experiments of brain hemorrhage. We also carried out rabbit cerebral hemorrhage experiments. The results of both saline simulation and animal experiments suggested that our monitoring system had a high phase detection precision, and it needed only about 0.030 4s to finish a single phase shift measurement, and the change of phase shift was directly proportional to the volume of saline or blood. The experimental results were consistent with theory. As a result, this system has the ability of real-time monitoring the progression of cerebral hemorrhage precisely, with many distinguished features, such as low cost, high phase detection precision, high sensitivity of response so that it has showed a good application prospect.
This study was aimed to improve the sensitivity of magnetic induction phase shift detection system for cerebral hemorrhage. In the study, a cerebral hemorrhage model with 13 rabbits was established by injection of autologous blood and the cerebral hemorrhage was detected by utilizing magnetic induction phase shift spectroscopy (MIPSS) detection method under the feature band. Sixty five groups of phase shift spectroscopy data were obtained. According to the characteristics of cerebral hemorrhage phase shift spectroscopy under the feature band, an effective method, B-F distribution, to diagnose the severity of cerebral hemorrhage was designed. The results showed that using MIPSS detection method under feature band, the phase shift obviously growed with increase of injection volume of autologous blood, and the phase shift induced by a 3-mL injection reached-7.750 3°±1.420 4°. B-F distribution could effectively diagnose the severity of cerebral hemorrhage. It can be concluded that the sensitivity of the cerebral hemorrhage magnetic induction detection system is improved by one order of magnitude with the MIPSS detection method under the feature band.