Stimulus and reward information encoded by population neurons in the primate prefrontal cortex and striatum / 生理学报

It has been reported that single-unit activity in the prefrontal cortex (PFC) and striatum represented visual stimulus and reward information. But how to encode these pieces of information is quite complex from the view of single-neuron activity. Different neurons represented stimulus or reward information in different task epochs with increasing or decreasing their activities relative to their baseline firing rates. The present paper was aimed to study whether population neurons in the two brain areas could stably encode task-relevant parameters in a whole trial period. We recorded single-unit activities in the lateral PFC (LPFC) and striatum while the monkey was performing a stimulus- reward prediction task, and analyzed the neuronal activities by the method of a multi-variable regression model and the linear support vector machine. The results showed that, although proportions of task-related neurons in the two areas varied largely in the whole trial period, LPFC population neurons encoded reward and stimulus information stably and reliably. Population neurons in the striatum encoded only reward information, not stimulus information. A group of neurons in the two areas represented combined information of stimulus and reward. Further analysis showed that LPFC neurons encoded reward information for a group of relevant stimuli, while striatal neurons encoded reward information for a specific stimulus. These results suggest that both LPFC and striatal population neurons are able to stably represent task-relevant information, but from different aspects of the task. The different strategies to encode information in the LPFC and striatum suggest their different contributions in reward-based decision making.

Reward information encoded by power of local field potentials in the primate prefrontal cortex and striatum / 生理学报

Prefrontal cortex and striatum are two major areas in the brain. Some research reports suggest that both areas are involved in many advanced cognitive processes, such as learning and memory, reward processing, and behavioral decision. Single-unit recording experiments have found that neurons in the prefrontal cortex and striatum can represent reward information, but it remains elusive whether and how local field potentials (LFPs) in the two areas encode reward information. To investigate these issues, we recorded LFPs simultaneously in the prefrontal cortex and striatum of two monkeys by performing a reward prediction task (a large amount reward vs a small amount reward). Recorded LFP signals were transformed from the time domain to the time and frequency domain using the method of short-time Fourier transform (STFT). We calculated the power in each frequency and time, and examined whether they were different in the two reward conditions. The results showed that power of LFPs in both the prefrontal cortex and striatum distinguished one reward condition from the other one. And the power in small reward trials was greater than that in large reward trials. Furthermore, it was found that the LFPs better encoded reward information in the beta band (14-30 Hz) rather than other frequency bands. Our results suggest that the LFPs in the prefrontal cortex and striatum effectively represent reward information, which would help to further understand functional roles of LFPs in reward processing.

Relationship between ambient fine particles and ventricular repolarization changes and heart rate variability of elderly people with heart disease in Beijing, China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To explore the effects of particulate matters less than 2.5 μm in aerodynamic diameter (PM2.5) on heart repolarization/depolarization and heart rate variability (HRV).</p><p><b>METHODS</b>We conducted a panel study for elderly subjects with heart disease in Beijing from 2007 to 2008. PM2.5 was measured at a fixed station for 20 h continuously each day while electrocardiogram (ECG) indexes of 42 subjects were also recorded repeatedly. Meteorological data was obtained from the China Meteorological Data Sharing Service System. A mixed linear regression model was used to estimate the associations between PM2.5 and the ECG indexes. The model was adjusted for age, body mass index, sex, day of the week and meteorology.</p><p><b>RESULTS</b>Significant adverse effects of PM2.5 on ECG indexes reflecting HRV were observed statistically and the strongest effect of PM2.5 on HRV was on lag 1 day in our study. However, there were no associations between PM2.5 and ECG indexes reflecting heart repolarization/depolarization. Additionally, the effects of PM2.5 on subjects with hypertension were larger than on the subjects without hypertension.</p><p><b>CONCLUSION</b>This study showed ambient PM2.5 could affect cardiac autonomic function of the elderly people with heart disease, and subjects with hypertension appeared to be more susceptive to the autonomic dysfunction induced by PM2.5.</p>

The impact of ambient particulate matter (PM10) on the population mortality for cerebrovascular diseases—a case-crossover study / 中华流行病学杂志

Objective To analyze the association between the concentration of ambient inhalable particulate matter (PM10) and population mortality for cerebrovascular diseases and to explore the impact of PM10 on cerebrovascular diseases.Methods Data including meteorological factors,air pollutants (NO2,SO2 and PM10) and cerebrovascular disease mortality in one district of Beijing from 2004 to 2008 were collected and both symmetric bidirectional case-crossover design and conditional logistic regression model were used to analyze the associations among them.Results After adjusting the influence of meteorological factors as daily average temperature and relative humidity,the single pollutant model showed that there was no significant lag effect.In the multipollutant model,the effect of the every 105.43 μg/m3 increase of ambient PM10 had a larger impact on the daily death of the cerebrovascular diseases with statistically significant difference (P＜0.05).The effect of ambient PM10 pollution on daily death of cerebrovascular diseases was significant for females,65 year-olds and in winter season.Conclusion Our data showed that elevated levels of ambient PM10was positively associated with the increase of cerebrovascular disease mortality.The elevated levels of ambient PM10 could lead to thc increase of the daily mortality on cerebrovascular diseases for females,elderly who were 65 or older and in winter seasons.

Preliminary study of source apportionment of PM10 and PM2.5 in three cities of China during spring / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study source apportionment of atmospheric PM10 (particle matter ≤ 10 µm in aerodynamic diameter) and PM2.5 (particle matter ≤ 2.5 µm in aerodynamic diameter) in Beijing,Urumqi and Qingdao, China.</p><p><b>METHODS</b>The atmospheric particle samples of PM10 and PM2.5 collected from Beijing between May 17th and June 18th, 2005, from Urumqi between April 20th and June 1st, 2006 and from Qingdao between April 4th and May 15th, 2005, were detected to trace the source apportionment by factor analysis and enrichment factor methods.</p><p><b>RESULTS</b>In Beijing, the source apportionment results derived from factor analysis model for PM10 were construction dust and soil sand dust (contributing rate of variance at 45.35%), industry dust, coal-combusted smoke and vehicle emissions (contributing rate at 31.83%), and biomass burning dust (13.57%). The main pollution element was Pb, while the content (median (minimum value-maximum value)was 0.216 (0.040-0.795) µg/m(3)) . As for PM2.5, the sources were construction dust and soil sand dust (38.86%), industry dust, coal-combusted smoke and vehicle emissions (25.73%), biomass burning dust (13.10%) and burning oil dust (11.92%). The main pollution element was Zn (0.365(0.126-0.808) µg/m(3)).In Urumqi, source apportionment results for PM10 were soil sand dust and coal-combusted dust(49.75%), industry dust, vehicle emissions and secondary particles dust (30.65%). The main characteristic pollution element was Cd (0.463(0.033-1.351) ng/m(3)). As for PM2.5, the sources were soil sand dust and coal-combusted dust (43.26%), secondary particles dust (22.29%), industry dust and vehicle emissions (20.50%). The main characteristic pollution element was As (14.599 (1.696-36.741) µg/m(3)).In Qingdao, source apportionment results for PM10 were construction dust (30.91%), vehicle emissions and industry dust (29.65%) and secondary particles dust (28.99%). The main characteristic pollution element was Pb (64.071 (5.846-346.831) µg/m(3)). As for PM2.5, the sources were secondary particles dust, industry dust and vehicle emissions (49.82%) and construction dust (33.71%). The main characteristic pollution element was Pb(57.340 (5.004-241.559) µg/m(3)).Enrichment factors of Zn, Pb, As and Cd in PM2.5 were higher than those in PM10 both in Beijing and Urumqi.</p><p><b>CONCLUSION</b>The major sources of the atmospheric particles PM10 and PM2.5 in Beijing were cement dust from construction sites and sand dust from soil; while the major sources of those in Urumqi were pollution by smoke and sand dust from burning coal. The major sources of the atmospheric particles PM10 in Qingdao were cement dust from construction sites; however, the major sources of PM2.5 there were secondary particles dust, industry dust and vehicle emissions. According to our study, the heavy metal elements were likely to gather in PM2.5.</p>

Time-series analysis on relationship between air pollution and mortality from circulatory system diseases among registered residents in Chaoyang district of Beijing / 中华预防医学杂志

<p><b>OBJECTIVE</b>This study aims to investigate relationship between daily concentration of PM(10), SO(2), NO(2) and daily mortality due to circulatory system diseases in Chaoyang district, Beijing.</p><p><b>METHODS</b>The time-series data of daily mortality from circulatory system diseases of registered residents in Chaoyang were obtained from Chaoyang District Center for Disease Control and Prevention. The daily concentration of sulfur dioxide (SO(2)), nitrogen dioxide (NO(2)), and particulate matter (PM(10)) were collected from Beijing Municipal Environmental Monitoring Center. And the routine monitoring meteorological data were collected from Beijing Meteorological Bureau, including daily mean temperature and daily mean relative humidity. The time-series analysis was then conducted to determine the relationship of mortality from circulatory system diseases with daily concentrations of SO(2), NO(2) and PM(10) by using Poisson regression with generalized additive model (GAM).</p><p><b>RESULTS</b>During January 2004 to September 2008, the cumulative death number from circulatory system diseases of registered residents in Chaoyang district of Beijing was 19 241, the daily average concentration of SO(2), NO(2), PM(10) was 48.7, 63.9, 146.1 µg/m(3), respectively. The single pollutant model showed an increase of daily concentration of PM(10), SO(2) and NO(2) by 10 µg/m(3) will augment the mortality from circulatory system diseases by 0.20% (95%CI: 0.01% - 0.39%), 0.36% (95%CI: -0.13% - 0.85%) and 0.30% (95%CI: -0.34% - 0.94%), respectively. In the multiple air pollutants models, combinatorial effects of PM(10) and SO(2) still positively correlated with increased mortality from circulatory system diseases (P < 0.05), whereas changes of the concentration of NO(2) had no significant effect on mortality from circulatory system diseases (P > 0.05).</p><p><b>CONCLUSION</b>Our findings in this study elucidated that changes of the concentration of PM(10) and SO(2) had a positive correlation with daily mortality from circulatory system diseases among the local residents in Chaoyang District, whereas the daily concentration of NO(2) was irrelevant with that.</p>

Time-series analysis on the association between gaseous air pollutants and daily mortality in urban residents in Tianjin / 中华流行病学杂志

Objective To study the association between sulphur dioxide, nitrogen dioxide and daily mortality in urban population from Tianjin. Methods Data on daily concentration of inhalable particulate matter, sulphur dioxide and nitrogen dioxide, daily mean temperature and relative humidity, daily cause-specific death counts were collected. Generalized additive models was used to explore the relationship between sulphur dioxide, nitrogen dioxide and daily mortality, after adjusting the effects of long-term and seasonal trend, weather conditions, and to analyze the potential effect of particulate matter and model parameters on relative risk estimates. Results Results showed that the daily concentrations of SO2 and NO2 were significantly associated with daily non-accidental and cardiovascular mortality but not associated with daily respiratory mortality. An increase of 10 μg/m3 in SO2 was associated with 0.56%(95%CI: 0.23%-0.89%)non-accidental morality, 0.49%(0.06%-0.93%)cardiovascular morality, respectively. An increase of 10μg/m3 in NO2 was associated with 0.94%(95% CI: 0.17%- 1.70%)non-accidental morality, 1.29%(0.29%-2.30%)cardiovascular morality, respectively. Conclusion Our findings suggested that exposure to SO2 and NO2 was significantly associated with daily cardiovascular and respiratory mortality in urban population in Tianjin.

Association between ambient air pollution and hospital emergency room visits for respiratory diseases: a case-crossover study / 中华流行病学杂志

Objective Using case-crossover design to explore the association between ambient air pollution and the hospital emergency room visits for respiratory diseases (International Classification of Diseases, tenth vision ICD-10: J00-J99) in Beijing, China. Methods Data regarding the daily hospital emergency room visits' of the respiratory diseases (ICD-10: J00-J99)were obtained in 2004.01.01-2005.12.31, from the Peking University Third Hospital and data on relevant air pollution and meteorological factors from the local municipal environmental monitoring center and meteorology bureau of Beijing, respectively. Time-stratified case-crossover technique was used to evaluate their relationships. Results from the bi-directional control sampling approach were compared with unidirectional approach. Results Using a unidirectional control sampling approach,the results obtained from a conditional logistic regression model (multi-pollutant model) after adjusting for meteorological variables, showed that the ORs of the hospital emergency room visits for the respiratory diseases associated with each 10 μg/m3 increment of PM10, SO2, NO2 were 1.010(95%CI: 1.005-1.014), 1.010(95%CI: 1.001-1.018) ,0.996(95%CI:0.983-1.009) respectively.In the bi-directional control sampling approach, the ORs were 1.002(95%CI:0.998-1.005)、 1.011 (95%CI:1.003-1.018)、 1.012(95%CI: 1.001-1.022). Conclusion Results from this study provided evidence that higher levels of ambient air pollutants increased the risk of hospital emergency room visits for respiratory diseases.

Time-series analysis of association between inhalable particulate matter and daily mortality among urban residents in Tianjin / 中华流行病学杂志

Objective To study the association between particulate matter less than 10 micron in aerodynamic diameter (PM10) and daily mortality among urban population in Tianjin.Methods We collected data of air quality, daily mean temperature and relative humidity, and daily cause-specific death counts, and used generalized additive models to explore the relationship between ambient particulate matter and daily mortality, after adjusting the effects of long-term and seasonal trend, weather conditions and other gaseous pollutants, such as sulfur dioxide and nitrogen dioxide.Results An increase of 10 μg/m3 in PM10 was associated with 0.45% (95%CI: 0.21-0.69) non-accidental morality, 0.60% (0.29-0.91) circulatory morality and 0.82% (0.04-1.61) respiratory morality, respectively. Conclusion Our findings indicated that the extent of exposure to PM10 was significantly associated with daily mortality in urban population in Tianjin, especially with the mortality rates on circulatory and respiratory diseases.

Association between ambient temperature and hospital emergency room visits for cardiovascular diseases:a case-crossover study / 中华流行病学杂志

Objective To explore the association between ambient average temperature and hospital emergency room visits for cardiovascular diseases(International Classification of Diseases,Tenth Vision ICD-10:I00-I99) in Beijing,China.Methods Data was collected on daily hospital emergency room visits for cardiovascular diseases from Peking University Third Hospital,including meteorological data(daily average temperature,relative humidity,wind speed,and atmospheric pressure) from the China Meteorological Data Sharing Service System,and on air pollution from the Beijing Municipal Environmental Monitoring Center.Time-stratified case-crossover design was used to analyze data on 4 seasolls.Results After adjusting data on air pollution,1 degree(℃) increase of ambient average temperature would associate with the emergency room visits of odds ratio(Ors)as 1.282(95%CI:1.250-1.315).1.027(95%CI:1.001-1.055),0.661(95%CI:0.637-0.687),and 0.960 (95%CI:0.937-0.984) in spring,summer,autumn,and winter respectively.After controlling the influence of relative humidity,wind speed,and atmospheric pressure,1℃ increase in the ambient average temperature would be associated with the emergency room visits on Ors value as 1.423 (95%CI:1.377-1.471).1.082(95%CI:1.041-1.124),0.633(95%CI:0.607-0.660)and 0.971(95%CI:0.944-1.000) in spring,summer,auttmm,and winter respectively.Conclusion These data on outcomes suggested that the elevated level of ambient temperature would increase the hospital emergeney room visits for cardiovascular diseases in spring and summer while the elevated level of ambient temperature would decrease the hospital emergency room visits for the cardiovascular diseases in autumn and winter,suggesting that patients with cardiovascular diseases should pay attention to the climate change.

The correlations between air quality and heart rate variability in aged susceptible people during Beijing Olympic Games 2008 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To observe the variations of the concentrations of air pollutants and explore the correlation between the heart rate variability (HRV) of the aged people and the air quality during Beijing Olympic Games 2008.</p><p><b>METHODS</b>A panel study design was adopted. A total of twenty-six over 55-year-old patients with coronary heart disease or angina pectoris or a symptom of myocardial ischemia at least for one year were enrolled as a panel and followed up five times by measuring HRV index and other related indexes from June to September in 2008. The correlations between the HRV of the aged people and the air quality was analyzed with the linear mixed-effect models according to the data of air pollutants and meteorological conditions collected simultaneously from Beijing Environmental Protection Bureau and Beijing Meteorological Bureau.</p><p><b>RESULTS</b>In single-pollutant mixed-effect models, the significant correlation was observed in the reduction of ambient PM(10), SO(2) and NO(2) with the improvement of the total power and high-frequency power (HF) of HRV in the panel subjects, and a 10 microg/m(3) decrease in PM(10), SO(2) and NO(2) level was correlated with 2.51% (95%CI: -3.80% - -1.22%, t = -1.99, P = 0.0497), 31.39% (95%CI: -52.24% - -10.53%, t = -1.99, P = 0.0497) and 42.72% (95%CI: -75.06% - -10.38%, t = -1.99, P = 0.0497) rises in total power of HRV respectively. A 10 microg/m(3) decrease in PM(10), SO(2) and NO(2) level was correlated with 3.46% (95%CI: -5.14% - -1.77%, t = -2.11, P = 0.0378), 40.63% (95%CI: -68.70% - -12.56%, t = -2.11, P = 0.0378) and 53.76% (95%CI: -97.97% - -9.56%, t = -2.11, P = 0.0378) rises in high-frequency power (HF) of HRV respectively.</p><p><b>CONCLUSION</b>It suggests that the air pollution reduction could improve the cardiovascular functions of the susceptible population.</p>

Association between the concentration of particulate matters and the hospital emergency room visits for circulatory diseases: a case-crossover study / 中华流行病学杂志

Objective To explore the association between the concentration of particulate matters with an aerodynamic diameter of <10 μm ( PM10 ) and the hospital emergency room visits for circulatory diseases ( International Classification of Diseases, tenth vision ICD-10 : 100-199) in Beijing, China. Methods We collected data for daily hospital emergency room visits of circulatory diseases ( ICD-10:I00-I99 ) from Peking University Third Hospital and from the ambient air PM10 through the Beijing Municipal Environmental Monitoring Center. A time-stratified case-crossover design was used to evaluate associations between circulatory disease health outcomes and PM10.Results The no-lagged unidirectional case-crossover design with 1:4 matched pairs had the highest odds ratios (ORs) between PM10 and the hospital emergency room visits for circulatory diseases. After adjusting the temperature and the relative humidity, a 10μg/m3 increased in the PM10 were found associated with the emergency room visits on value of ORs of 1.006(95% CI:1.003-1.008) for the total circulatory diseases ( ICD-10:I00-I99), 1.003 (95% CI:0.996-1.010) for coronary heart disease ( ICD-10:I20-I25 ), 1.005 ( 95 % CI:0.997-1.013 ) for cardiac arrhythmia ( ICE)-10:I47-I49), 1.019 (95 % CI:1.005-1.033 ) for heart failure disease ( ICD-10:I50 ),and 1.003 ( 95 % CI : 0.998-1.007 ) for cerebrovascular diseases ( ICD-10:I60-I69 ), respectively. Conclusion These findings suggested that elevated levels of ambient PM10 were positively associated with hospital emergency room visits for the total number of circulatory diseases and heart failure disease.

Reproductive effects of occupational exposure to mercury on female workers in China: a meta-analysis / 中华流行病学杂志

<p><b>OBJECTIVE</b>To analyze and evaluate the reproductive effects of occupational exposure to mercury among female workers and to identify relative sensitive indicators.</p><p><b>METHODS</b>Documents on the relations of occupational exposure to mercury and reproductive effects on female workers were collected through computer and manually that were published in Chinese language during 1989-2006. After strict selection, homogeneity test and integrated analysis for the abstracted data of the eligible studies were conducted using Review Manager Statistic Software. Combined RR value was used as the index for total effect on each project for Meta-analysis.</p><p><b>RESULTS</b>In total, 14 original research papers were included (totally 2148 subjects and 2044 controls). When comparing to the controls, the occupational exposure to mercury was significantly associated with longer menstrual period (RR = 1.82, 95% CI: 1.45-2.30), menstrual cycle delay (RR = 2.03, 95% CI: 1.74-2.37) and the changes of menstrual blood volume (RR = 2.06, 95% CI: 1.47-2.09), dysmenorrhea (RR = 2.14, 95% CI: 1.54-2.99), pregnancy-induced hypertension (RR = 2.17, 95% CI: 1.32-3.57), stillbirths (RR = 2.54, 95% CI: 1.41-4.56) and low birth weight (RR = 3.39, 95% CI: 1.38-8.33)/birth defect (RR = 2.67, 95% CI: 1.55-4.60) of their offspring (P < 0.05).</p><p><b>CONCLUSION</b>Occupational exposure to mercury could cause dysfunction of the menstrual period, menstrual cycle, menstrual blood volume, as well as dysmenorrhea for female workers being exposed to mercury and inducing adverse reproductive outcomes, including pregnancy-induced hypertension, stillbirth, low birth weight and birth defects of their offspring.</p>

Risk factors for allergic asthma in a case-control study among adults / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the risk factors allergic asthma in adult as well as the indoor environmental risk factors.</p><p><b>METHODS</b>Case-control study was used to collect the information from 102 cases of adults' allergic asthma and 394 controls. The information included general social demographic characteristics, disease history, smoking history, occupation, indoor environmental situation and genetic history of the families.</p><p><b>RESULTS</b>The case group had higher proportion of the history on occupational dust exposure than the control group (P < 0.05, OR = 1.78) with statistical significance. Poorer housing condition were more likely to cause adult allergic asthma or onset, with an odds ratio of 3.24. The results also showed that there was a correlation between the frequency of "quilt solarization" and adult allergic asthma (P < 0.10, OR = 1.53). We also found that the frequency of having woody floor in the living room of the patients cases was higher than that in the controls (P < 0.01, OR = 2.33) so as the degree of indoor cooking-oil fume contamination (P < 0.01, OR = 2.52). The statistical significant correlation was also found between the adult allergic asthma and the history of asthma or chronic bronchitis of their parents (P < 0.01, OR = 2.32).</p><p><b>CONCLUSIONS</b>The study showed that the indoor environmental risk factors as poor housing condition, fewer frequency of solarization for quilts, woody floor in the living room as well as indoor cooking-oil fume contamination were the possible risk factors related to adult allergic asthma. Occupational dust exposure and the family genetic history were also the possible risk factors. The study indicated that adult allergic asthma was a multi-factorial complex disease and the interaction of environmental and genetic risk factors played an important role in the onset of this disease.</p>

Relationship of the hair content of rare earth elements in young children aged 0 to 3 years to that in their mothers living in a rare earth mining area of Jiangxi / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the relationship of hair content of rare earth elements (REEs) in the young children aged 0 - 3 years to that in their mothers living in a rare earth mining area of Jiangxi Province.</p><p><b>METHODS</b>Content of five kinds of REEs, i.e., lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd) and samarium (Sm) were determined for the hair-root samples collected from 71 young children and 62 of their mothers by inductively coupled plasma source mass spectrometry (ICP-MS).</p><p><b>RESULTS</b>The mean hair content of REEs (e.g., La) was the highest (2,202.90 ng/g) in the young children living in the place nearest to the REE mining area, next (471.72 ng/g) was in those nearer to the REE mining area, and the lowest (97.37 ng/g) was in those in the control area. And, the hair content of REEs in the mothers was the same as that in their children, i.e, the mean content of La was the highest (1,510.21 ng/g) in high-exposure area, next (241.63 ng/g) was that in the low-exposure area, and the lowest (59.15 ng/g) was that in the control area, with P < 0.001. Pair-comparison analysis for the means showed that the average hair level of five kinds of REEs in the young children was two times high as their mothers' (P < 0.001). For example, the hair level of La was 533.83 ng/g in the young children and 279.78 ng/g in their mothers, respectively. Simple linear regression analysis showed that there was a significant correlation between the hair levels of each kind of REEs in the young children and those in their mothers, with a correlation coefficient of more than 0.75, e.g., that of La was 0.878 (P < 0.01).</p><p><b>CONCLUSIONS</b>The hair level of REEs can be used as a bio-marker to reflect body's level of exposure to REEs. The hair level of REEs in young children and their mothers decreased with the increase of the distance from their home to rare earth mining area. Young children living in the area with REEs mining may be the high-exposure population, and their hair level of REEs was significantly higher than that in their mothers and more attention should be paid to them.</p>

Distribution Pattern of Rare Earth Elements in Hair Samples of Young Children Aged 0-3yrs in Rare Earth Ore Area / 环境与健康杂志

Objective To study the distribution pattern of rare earth elements (REEs) in hair of young children. Methods REEs level and distribution pattern in hair of young children aged 0～30 months in RE ore area were studied. All the lanthanide elements were determined with inductively coupled plasma mass spectrometer (ICP_MS) in 20 hair samples of young children aged 0_3yrs, 10 samples from RE ore area and 10 samples as controls from Xunwu county, Jiangxi, China. Results 15 kinds of REEs in each sample were all detected. There were significant differences between higher children's hair REEs levels of RE ore area and those lower levels of control site (P

Relationship Between Dust Storms and Acute Impacts in Baotou City / 环境与健康杂志

Objective To make it clear whether dust storms may produce same acute adverse impacts on community population. Methods 2 primary schools in Baotou City were selected. During the period of dust storm in March of 2004 an investigation among 918 pupils from third to fifth grades and 1 770 parents of them was conducted by questionnaires. Meanwhile the concentrations of PM2.5 were also determined. Results On the day of dust storms developed the concentrations of PM2.5 obviously increased (212.9 ?g/m3)then decreased rapidly(