Objective To develop the software for the assessment of radionuclide concentration and doses from atmospheric dispersion. Methods Based on procedures for radionuclide atmospheric dispersion and dose assessment in IAEA publications (safety series reports No. 19), a parameter database was constructed using Microsoft Access, and the dispersion model and dose assessment methods were computerized using Microsoft Visual Basic 6.0, then we got the dose assessment software for radionuclide atmospheric dispersion. Results Atmospheric radionuclide concentration and public effective dose in a year could be estimated rapidly with the present software. Conclusion The present software provides a practical and rapid tool for evaluation and assessment the influence of radionuclide atmospheric dispersion, which can be used in the evaluation of atmospheric radionuclide concentration in routine monitoring or nuclides/radiological emergency, and also can be used as the screening evaluation in environmental surveillance.

Objective To survey the 238U radioactivity level in the surface soil in the Beijing-Tianjin-Hebei Border (BTHB) region,and to prepare a high resolution distribution map of 238U activity concentrations.Methods The soil samples were collected in a grid (10 km × 10 km).The activity concentrations of 238U in soil samples were measured by using HPGe γ spectrometry.The distribution of the activity concentrations of 238U in soil samples was mapped by the aid of MAPGIS software.Results In total,416 samples were collected and measured.The activity concentrations of 238U were in the range of 0.1-106.0 Bq/kg,with an average of 34.7 Bq/kg.The 238U activity concentration distribution map showed that 238U activity concentration was in the range of 15-55 Bq/kg mostly on the surface soil in the BTHB region.Conclusions The map of 238U activity concentration shows the distribution of 238U activity concentration in the BTHB region.It is of importance to map the distribution of 238U activity concentration in the BTHB region,by converting a huge amount of data into the simple and intuitive graphics,and for evaluating the regional environmental radioactivity and studying the radioactive substance migration within the locality.

Objective To develop a radionuclide parameter database on internal contamination in nuclear emergencies. Methods By researching the radionuclides composition discharged from different nuclear emergencies, the radionuclide parameters were achieved on physical decay, absorption and metabolism in the body from ICRP publications and some other publications. The database on internal contamination for nuclear incidents was developed by using MS Visual Studio 2005 C# and MS Access programming language. Results The radionuclide parameter database on internal contamination in nuclear emergency was established. Conclusions The database may be very convenient for searching radionuclides and radionuclide parameter data discharged from different nuclear emergencies, which wonld be helpful to the monitoring and assessment of internal contamination in nuclear emergencies.

BACKGROUND:The mechanism and effect of glycogen synthase kinase 3β(GSK-3β) in the differentiation of cardiac stem cel s into cardiomyocytes are stil unclear, although GSK-3βis closely related to the life activities of cel s.
OBJECTIVE:To investigate the changes of GSK-3βexpression in the treatment of myocardial infarction in rats undergoing cardiac stem cel transplantation.
METHODS:The isolation and culture of cardiac stem cel s were performed in 10 neonatal rats. Lentivirus overexpressing GSK-3βor LacZ (control) was constructed and transferred into cardiac stem cel s. Animal model of myocardial infarction was made in 30 Sprague-Dawley rats. Six weeks after model preparation, rat models were assigned into GSK-3β, LacZ or PBS group. GSK-3βor LacZ overexpressing cardiac stem cel solution or PBS in equal volume was injected into the rat myocardium, respectively. Four weeks after transplantation, the cardiac function and myocardial col agen production in rats were detected and compared.
RESULTS AND CONCLUSION:Compared with the other two groups, the left ventricular ejection fraction was significantly higher, and the left ventricular end diastolic diameter was significantly lower in the GSK-3βgroup (P<0.05). Hydroxyproline content, type I col agen mRNA, and type III col agen mRNA expression were significantly lower in the GSK-3βgroup than the other two groups (P<0.05). Findings from Masson staining showed that the content of blue-stained col agen was significantly lower in the GSK-3βgroup than the LacZ group. Moreover, lowest myocardial infarction size was found in the GSK-3βgroup (P<0.05). Al these experimental findings show that GSK-3 overexpression plays a positive role in promoting the therapeutic effect of cardiac stem cel transplantation.

Objective To explore the effeetiviness of the method of LabSOCS(Laboratory sourceless calibration software)efficiency calibration in laboratory rapid analysis for emergency monitoring of nuclear incidents.Methods The detection efficiency of three kinds of environmental samples in emergency monitoring Wag calculated bY using the LabSOCS efficiency calibration method,and compared with the values that were obtained by way of radioactive source calibration method.Results The maximum relative deviation of the detection efficiency between the two methods was less than 15%,and the values with relative deviation less than 5%accounted for 70%.Conclusions The LabSOCS efficiency calibration method might take the place of radioactive source efficiency calibration method,and meet the requirement of rapid analysis in emergency monitoring of the nuclear incidents.

Objective To measure the current environmental radioactivity levels in some districts of Yunnan Province,and to estimate the external doses to local residents.Methods The surface soil,aerosol and water samples were collected and analyzed by HPGe gamma spectrometry.Based on the estimation model selected by Ministry of Health in the nationwide soil survey,the doses to local residents from 238U,226Ra,232Th,40K and 137Cs in environmental samples were estimated.CARI-6 software issued by FAA (Federal Aviation Administration ) was used to estimate cosmic radiation dose to the local population.Results The external annual dose rate to the local people was 1.13 mSv per year,of which 0.52 mSv per year was contributed by natural radionuclides in soil,0.6 μ Sv per year by 137 Cs in soil and 0.61 mSv per year by cosmic radiation.Conclusions The cosmic radiation and natural radionuclides in soil might contribute 99.95％ of external exposure dose,while artificial radionuclide 137Cs contribute 0.05％ of external exposure dose.

Objective To test a full range of processes of sample collection,preparation,measurement and analysis by conducting the intercomparison of gamma-ray spectrometry measurement and analysis of radionuclides among key laboratories,so as to facilitate the development of gamma-ray spectrometry measurement and analysis technology.Methods To complete the collection and preparation of soil samples by Chinese Center for Disease Control and Prevention (CDC) laboratory and to measure and analyze the content in two soil samples of 214Pb,214Bi,208TI,228Ac,40K and 137Cs by three laboratories using gamma-ray spectrometry.Results The value calculated by any two laboratories were less than 1 in terms of assessment standards agreed by these three laboratories and based on the activity concentrations and the total uncertainty reported from them.The measurement results from our lab were acceptable.Conclusions Measurement results from these three laboratories are in agreement to some extent.This intercomparison activity has tested the analytical ability of the three laboratories and raised the level of our laboratory in testing homogeneity of sample preparation.

Objective To investigate the clinical value of the gated blood pool imaging phase analysis method in the evaluation of left ventricular mechanical synchronization in patients with chronic heart failure. Methods A total of 169 patients with chronic heart failure were enrolled in our study , using gated blood pool imaging phase analysis method to obtain left ventricular phase angle width ( PHB) and left ventricular phase angle standard deviation ( PSD) as evaluating left ventricular mechanical synchrony index; using tissue Doppler imaging (TDI) measurement of the standard deviation of systolic peak time(Ts-SD) of each segment by using the current prevailing 12 non-apical segments analysis method as evaluating left ventricular mechanical synchrony index, and parameters derived from both methods were compared. Results LVPHB was highly correlated with Ts-SD (r = 0. 83 ,P = 0. 000 ) . LVPSD was modestly correlated with Ts-SD ( r - 0. 69, P = 0. 000) . The ejection fraction measured by echocardiography was (42.93 ± 14. 89) % ,which was significantly higher than that measured by ERNA (39. 76 ± 17. 89)% (P <0. 01). Conclusions The evaluation of left ventricular mechanical synchrony in patients with chronic heart failure by the gated blood pool imaging can provide similar information with TDI, which can simultaneously measure two ventricular functions and get more accurate measurement of ejection fraction. Cardiac resynchronization therapy patients can be identified by combining two kinds of approaches, and cardiac resynchronization therapy responders could be improved as well. More patients with heart failure can benefit from cardiac resynchronization therapy therapy.

Objective To establish a method for estimating internal dose from aerosol inhalation in non-uranium miners.Methods Aerosol samples in a tunnel in Dongchuan Copper Mine in Yunnan Province were collected by portable high flux air sampler.Radionuclides collected at the sampler filters were analyzed by the gamma spectrometry.Annual committed effective dose due to inhalation of the aerosol dust was estimated using the formula provided by ASTM.Results Radionuclides collected in two aerosol samples were anlayzed,the annual committed effective doses due to inhalation of 1 μm and 5 μm aerosol were estimated.Conclusions The method of using high flux air sampling and gamma spectrometry is explored to estimate the dose from aerosol inhalation.

Objective To estimate the dose to non-uranium miners from external exposure.Methods Ore samples of non-uranium mines were collected in site and analyzed with gamma spcetrometry,then annual dose to the miners was estimated based on the measured radioactivities of radionuclides.Results Thirty-two ore samples in thirteen mines in seven provinces were collected and analyzed.Among them,radioactivity concentrations in two samples were higher than others,and the annual doses from external exposure to the radionuclides in the two ore samples were estimated to be higher than 1 mSv/a.Conclusions Gamma spectrometry is fit for determining the radionuclides concentrations and its results can be used for estimating dose from external exposure in non-uranium mines.