[Stimulus and reward information encoded by population neurons in the primate prefrontal cortex and striatum].

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.

[Reward information encoded by power of local field potentials in the primate prefrontal cortex and striatum].

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.

Visual pattern discrimination by population retinal ganglion cells' activities during natural movie stimulation.

In the visual system, neurons often fire in synchrony, and it is believed that synchronous activities of group neurons are more efficient than single cell response in transmitting neural signals to down-stream neurons. However, whether dynamic natural stimuli are encoded by dynamic spatiotemporal firing patterns of synchronous group neurons still needs to be investigated. In this paper we recorded the activities of population ganglion cells in bullfrog retina in response to time-varying natural images (natural scene movie) using multi-electrode arrays.

[Evaluation of excess mortality caused by PM2.5 in four typical Chinese big cities].

Objective: To evaluate the adverse effects of particulate matter ≤ 2.5 µm in aerodynamic diameter (PM2.5) on public health in four typical cities: Beijing, Shanghai, Guangzhou and Xi'an.

[Preliminary study of source apportionment of PM10 and PM2.5 in three cities of China during spring].

Objective: 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.

Relationship between ambient fine particles and ventricular repolarization changes and heart rate variability of elderly people with heart disease in Beijing, China.

Objective: 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).

[The impact of ambient particulate matter (PM10) on the population mortality for cerebrovascular diseases-a case-crossover study].

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.

[Association between ambient PM10/PM2.5 levels and population mortality of circulatory diseases: a case-crossover study in Beijing].

Objective: To explore the association between levels of ambient particulate matters (PM10 and PM2.5) and population mortality of circulatory diseases (ICD10: I00~I99) in Beijing.

Methods: The daily data of ambient PM2.

[Relationship between daily mean temperature and emergency department visits for respiratory diseases: a time-series analysis].

Objective: To quantitatively evaluate the influences of daily mean air temperature (DMT) on Emergency Department Visits (EDVs) for the respiratory diseases.

Methods: The EDV data from medical records for respiratory diseases in Peking University Third Hospital between January 2004 and June 2009 were collected. The data of the air pollutants (SO(2), NO(2) and PM(10)) and meteorological factors at the same time periods were also collected from the local authorities of Beijing.

[Time-series analysis on relationship between air pollution and mortality from circulatory system diseases among registered residents in Chaoyang district of Beijing].

Objective: 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.

Methods: 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.

Sub-micrometer particulate air pollution and cardiovascular mortality in Beijing, China.

Background: While the link between particulate matter and cardiovascular mortality is well established, it is not fully investigated and understood which properties of the aerosol might be responsible for the health effects, especially in polluted mega-city areas.

Objectives: Our goal was to explore the association between daily cardiovascular mortality and different particle metrics in the sub-micrometer range in Beijing, China.

Methods: We obtained daily counts of cause-specific cardiovascular deaths in the Beijing urban area for the period March 2004 to August 2005.

Associations between size-segregated particle number concentrations and respiratory mortality in Beijing, China.

Numerous studies have described the adverse associations between particle mass and respiratory health. The aim of the study was to analyze the associations of particle properties, especially size-segregated particle number concentrations (PNC), and respiratory mortality in Beijing, P.R.

[Time-series analysis of association between inhalable particulate matter and daily mortality among urban residents in Tianjin].

Objective: To study the association between particulate matter less than 10 micron in aerodynamic diameter (PM(10)) 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/m(3) in PM(10) was associated with 0.

[Association between ambient air pollution and hospital emergency room visits for respiratory diseases: a case-crossover study].

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.

[Time-series analysis on the association between gaseous air pollutants and daily mortality in urban residents in Tianjin].

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.

Size-segregated particle number concentrations and respiratory emergency room visits in Beijing, China.

Background: The link between concentrations of particulate matter (PM) and respiratory morbidity has been investigated in numerous studies.

Objectives: The aim of this study was to analyze the role of different particle size fractions with respect to respiratory health in Beijing, China.

Methods: Data on particle size distributions from 3 nm to 1 µm; PM10 (PM ≤ 10 µm), nitrogen dioxide (NO(2)), and sulfur dioxide concentrations; and meteorologic variables were collected daily from March 2004 to December 2006.

[Status and distribution of atmospheric ultrafine particles during Olympics Games in Beijing].

Objective: To understand the characteristics of size and concentration of the ultrafine particles (UFPs) during the 2008 Olympics in Beijing, as well as the influencing factors for number concentration of UFPs.

Methods: Ultrafine particle monitor model 3031, manufactured by USA TSI Co., was used to monitor the daily number concentration of 20-500 nm particles, and descriptive analysis was conducted based on the data collected.

Exposures to particulate matter and polycyclic aromatic hydrocarbons and oxidative stress in schoolchildren.

Background: Air pollution is known to contribute to respiratory and cardiovascular mortality and morbidity. Oxidative stress has been suggested as one of the main mechanisms for these effects on health.

Objective: The aim of this study was to analyze the effects of exposure to particulate matter (PM) with aerodynamic diameters < or = 10 microm (PM10) and < or = 2.

[Association between ambient temperature and hospital emergency room visits for cardiovascular diseases: a case-crossover study].

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 seasons.

[The correlations between air quality and heart rate variability in aged susceptible people during Beijing Olympic Games 2008].

Objective: 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.

Methods: 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.

Asian Dust Storm and pulmonary function of school children in Seoul.

Health effects of the Asian Dust Storm (ADS) have not been evaluated adequately, even though it may affect health of people in East Asia. This study was conducted to evaluate whether the ADS affects particulate air pollution and pulmonary function of children. We studied 110 school children in Seoul, Korea with daily measurement of peak expiratory flow rate (PEFR) from May 13 to June 15, 2007.

Ambient temperature and mortality: an international study in four capital cities of East Asia.

Extreme ambient temperature has been associated with increased daily mortality across the world. We describe the ambient temperature-mortality association for four capital cities in East Asia, Seoul, Beijing, Tokyo, and Taipei, and identify a threshold temperature for each city and the percent increase in mortality. We adapted generalized linear modeling with natural cubic splines (GLM+NS) to examine the association between daily mean apparent temperature (AT) and total mortality, as well as mortality due to respiratory (RD) and cardiovascular (CVD) causes in a threshold model.

[Association between the concentration of particulate matters and the hospital emergency room visits for circulatory diseases: a case-crossover study].

Objective: To explore the association between the concentration of particulate matters with an aerodynamic diameter of < 10 microm (PM(10)) and the hospital emergency room visits for circulatory diseases (International Classification of Diseases, tenth vision ICD-10:I00-I99) 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 PM(10) through the Beijing Municipal Environmental Monitoring Center. A time-stratified case-crossover design was used to evaluate associations between circulatory disease health outcomes and PM(10).

[Reproductive effects of occupational exposure to mercury on female workers in China: a meta-analysis].

Objective: To analyze and evaluate the reproductive effects of occupational exposure to mercury among female workers and to identify relative sensitive indicators.

Methods: 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.

[Research on the health risk assessment of chemical pollutants in reclaimed water used for streets watering].

It is the first time for this research to utilize the method of health risk assessment. Combining with Beijing reclaimed water project, the exposure dose level and health risk to contact people are investigated and studied. The risk assessment model is built, and the exposure parameters of occupational workers and common people are provided, when reclaimed water was used for streets watering.