North China City Research Articles

Serum Bisphenol A, glucose homeostasis, and gestational diabetes mellitus in Chinese pregnant women: a prospective study.

Lab studies have suggested that exposure to Bisphenol A (BPA) could disturb glucose homeostasis, but epidemiologic studies are limited and show inconsistent results for pregnant women. For this, 535 pregnant women were selected from a pregnant women cohort established in Tangshan City in North China between 2013 and 2014. Serum concentrations of BPA were measured in the early term of pregnancy, and fasting glucose and insulin levels were repeatedly measured in each of three terms of pregnancy (early, middle, and late). Gestational diabetes mellitus (GDM) were examined by Oral Glucose Tolerance Test (OGTT) in the middle and late terms of pregnancy. BPA was detected in 97.5% of pregnant women with a median of 6.50ng/ml. Natural log-transformed BPA (Ln BPA) was positively associated with fasting glucose level (β (95% CI): 0.038 (0.015~0.061)), fasting insulin level (0.195 (0.069~0.321)), and homeostasis model insulin resistance index (HOMA-IR) (0.226 (0.087~0.364)) in the middle term of pregnancy by multiple linear regression model after adjusting for potential confounders. After serum BPA levels were divided into three groups (low, middle, and high), BPA showed a positive dose-response relationship with blood glucose, insulin, and HOMA-IR in the middle term of pregnancy. Increased BPA concentration tended to increase the RR of GDM although not statistically significant (risk ratio: 2.51 (95% CI: 0.68~9.30) for high vs low tertile of BPA concentrations). These findings suggested that exposure to BPA might affect glucose homeostasis and the middle term of pregnancy was a potentially sensitive period.

Sensitivity of PM2.5 to NOx emissions and meteorology in North China based on observations

This study examines the sensitivity of daily PM2.5 to NOx emissions and meteorology using in situ observations from main cities of North China (NC). NC cities are divided into low-, medium-, and high-emission groups by the ranking of their 4-year mean NO2. For each emission group, daily NO2 levels are used to divide the days into good-, medium-, and bad-meteorological conditions. Regardless of their emission levels, all cities reveal significant decreases (96%‐172%) in daily PM2.5 levels from bad to good meteorological conditions. The largest difference in PM2.5 concentrations between the emissions groups is found under bad meteorological conditions, with 56% higher PM2.5 in high-emission cities than low-emission cities, indicating PM2.5 under bad meteorological conditions has the largest sensitivity to emissions. The high-emission, bad-meteorology group saw a 24% decrease in mean daily PM2.5 levels from 2017, a high-emission year, to 2019, a low-emission year. However, under good meteorological conditions, the high-emissions group shows an increase of 8.8 μg/m3 in mean daily PM2.5 from 2017 to 2019 with a 2.6% increase in the possibility of high PM2.5. These results suggest the current emission reduction measures are more effective in controlling PM2.5 in high-emission cities under bad meteorological conditions than under other meteorological conditions.

Ambient air pollution and cause-specific risk of hospital admission in China: A nationwide time-series study.

The impacts of air pollution on circulatory and respiratory systems have been extensively studied. However, the associations between air pollution exposure and the risk of noncommunicable diseases of other organ systems, including diseases of the digestive, musculoskeletal, and genitourinary systems, remain unclear or inconclusive. We aimed to systematically assess the associations between short-term exposure to main air pollutants (fine particulate matter [PM2.5] and ozone) and cause-specific risk of hospital admission in China over a wide spectrum of human diseases. Daily data on hospital admissions for primary diagnosis of 14 major and 188 minor disease categories in 252 Chinese cities (107 cities in North China and 145 cities in South China) from January 1, 2013, to December 31, 2017, were obtained from the Hospital Quality Monitoring System of China (covering 387 hospitals in North China and 614 hospitals in South China). We applied a 2-stage analytic approach to assess the associations between air pollution and daily hospital admissions. City-specific associations were estimated with quasi-Poisson regression models and then pooled by random-effects meta-analyses. Each disease category was analyzed separately, and the P values were adjusted for multiple comparisons. A total of 117,338,867 hospital admissions were recorded in the study period. Overall, 51.7% of the hospitalized cases were male, and 71.3% were aged <65 years. Robust positive associations were found between short-term PM2.5 exposure and hospital admissions for 7 major disease categories: (1) endocrine, nutritional, and metabolic diseases; (2) nervous diseases; (3) circulatory diseases; (4) respiratory diseases; (5) digestive diseases; (6) musculoskeletal and connective tissue diseases; and (7) genitourinary diseases. For example, a 10-μg/m3 increase in PM2.5 was associated with a 0.21% (95% CI 0.15% to 0.27%; adjusted P < 0.001) increase in hospital admissions for diseases of the digestive system on the same day in 2-pollutant models (adjusting for ozone). There were 35 minor disease categories significantly positively associated with same-day PM2.5 in both single- and 2-pollutant models, including diabetes mellitus, anemia, intestinal infection, liver diseases, gastrointestinal hemorrhage, renal failure, urinary tract calculus, chronic ulcer of skin, and back problems. The association between short-term ozone exposure and respiratory diseases was robust. No safety threshold in the exposure-response relationships between PM2.5 and hospital admissions was observed. The main limitations of the present study included the unavailability of data on personal air pollution exposures. In the Chinese population during 2013-2017, short-term exposure to air pollution, especially PM2.5, was associated with increased risk of hospitalization for diseases of multiple organ systems, including certain diseases of the digestive, musculoskeletal, and genitourinary systems; many of these associations are important but still not fully recognized. The effect estimates and exposure-response relationships can inform policy making aimed at protecting public health from air pollution in China.

Source apportionment of particulate matter based on numerical simulation during a severe pollution period in Tangshan, North China

Facing serious air pollution problems, the Chinese government has taken numerous measures to prevent and control air pollution. Understanding the sources of pollutants is crucial to the prevention of air pollution. Using numerical simulation method, this study analysed the contributions of the total local emissions and local emissions from different sectors (such as industrial, traffic, resident, agricultural, and power plant emissions) to PM2.5 concentration, backward trajectory, and potential source regions in Tangshan, a typical heavy industrial city in north China. The impact of multi-scale meteorological conditions on source apportionment was investigated. From October 2016 to March 2017, total local emissions accounted for 46.0% of the near-surface PM2.5 concentration. In terms of emissions from different sectors, local industrial emissions which accounted for 23.1% of the near-surface PM2.5 concentration in Tangshan, were the most important pollutant source. Agricultural emissions were the second most important source, accounting for 10.3% of the near-surface PM2.5 concentration. The contributions of emissions from power plants, traffic, residential sources were 2.0%, 3.0%, and 7.2%, respectively. The contributions of total local emissions and emissions from different sectors depended on multi-scale meteorological conditions, and static weather significantly enhanced the contribution of regional transport to the near-surface PM2.5 concentration. Eight cluster backward trajectories were identified for Tangshan. The PM2.5 concentration for the 8 cluster trajectories significantly differed. The near-surface PM2.5 in urban Tangshan (receptor point) was mainly from the local emissions, and another important potential source region was Tianjin. The results of the source apportionment suggested the importance of joint prevention and control of air pollution in some areas where cities or industrial regions are densely distributed.

Chemical Compositions and Source Analysis of PM2.5 during Autumn and Winter in a Heavily Polluted City in China

As one of the biggest cities in North China, Jinan has been suffering heavy air pollution in recent decades. To better characterize the ambient particulate matter in Jinan during heavy pollution periods, we collected daily PM2.5 (particulate matter with aerodynamic diameters equal to or less than 2.5 μm) filter samples from 15 October 2017 to 31 January 2018 and analyzed their chemical compositions (including inorganic water-soluble ions (WSIs), carbonaceous species, and inorganic elements). The daily average concentration of PM2.5 was 83.5 μg/m3 during the sampling period. A meteorological analysis revealed that both low wind speed and high relative humidity facilitated the occurrence of high PM2.5 pollution episodes. A chemical analysis indicated that high concentrations of water-soluble ions, carbonaceous species, and elements were observed during heavy pollution days. The major constituents of PM2.5 in Jinan were secondary aerosol particles and organic matter based on the results of mass closure. Chemical Mass Balance (CMB) was used to track possible sources and identified that nitrate, sulfate, vehicle exhaust and coal fly ash were the main contributors to PM2.5 during heavy pollution days in Jinan, accounting for 25.4%, 18.6%, 18.2%, and 13.3%, respectively.

Characteristics of Volatile Organic Compounds during Different Pollution Periods in Winter in Yuncheng, a Typical City in North China

ABSTRACT The composition characteristics and health risks of volatile organic compounds (VOCs) and their effects on secondary organic aerosol (SOA) during polluted and clean periods in winter 2018 for Yuncheng, a typical city in North China, were studied. The average concentration of VOCs was 2.3 times higher during the polluted period (105.29 µg m–3) than the clean period (45.78 µg m–3), whereas the average concentrations of the alkanes, alkenes, and aromatics were 3.4, 2.1, and 3.9 times higher, respectively, during the polluted period than the clean period. In addition, the VOC concentration was significantly influenced by meteorological conditions. Using positive matrix factorization (PMF), seven sources of atmospheric VOCs were identified, with the largest factors being vehicle emission (27.89%), coal combustion (23.37%), liquefied petroleum gas/natural gas evaporation (18.30%), and industrial emission (15.51%). Vehicle emission (30.04%) was the primary contributor during the polluted period, whereas coal combustion (33.53%) was the primary contributor during the clean period. The SOA formation potential (which almost exceeded 80%) was influenced by industrial emission (28.80%), solvent usage (26.30%), and vehicle emission (24.85%). Additionally, an assessment of the health risks of six aromatics based on the health risk exposure model of the United States Environmental Protection Agency revealed that the non-cancer risk was higher during the polluted period (6.61 × 10–2) than the clean period (2.20 × 10–2) but still below the Environmental Protection Agency (EPA) limit (1.00) and therefore negligible for the exposed population. However, the carcinogenic index of benzene (2.85 × 10–5 to 5 × 10–5) exceeded 10–6, suggesting a higher carcinogenic risk. Large-scale energy restructuring during recent years has sharply reduced coal combustion, but the VOC concentration has dramatically increased due to vehicle emission. Hence, regulating vehicle emissions is an effective strategy for controlling VOCs in Yuncheng.

Comparison of PM2.5 Chemical Compositions during Haze and Non-haze Days in a Heavy Industrial City in North China

This study aimed to determine the chemical composition, sources and contributing factors of airborne PM2.5 (particulate matter with an aerodynamic diameter ≤ 2.5 µm) during a haze episode in Zibo, a heavy industrial city in China. Samples of PM2.5 were collected 8–27 January 2018 and analyzed for water-soluble inorganic ions (WSIs), trace elements (TEs), organic carbon (OC) and elemental carbon (EC). The PM2.5 concentration was 76.78% higher during the haze (mean ± standard deviation [SD] = 211 ± 39 µg m–3) than before it (49 ± 38 µg m–3), and the dominant ions were NO3–, SO42– and NH4+. Additionally, an elevated TE concentration was observed during the episode (exceeding the pre- and post-haze values by 54.70% and 31.98%, respectively), with crustal elements (K, Al, Ca, Si, Na, Fe and Mg), the most abundant elemental components, accounting for 88.64%. Carbonaceous species (OC and EC) contributed 15.45% of the PM2.5 on haze days and slightly more on non-haze days. The NO3–/SO42– and OC/EC ratios indicated that coal combustion and motor vehicle emission were the primary sources of pollution, and back-trajectory analysis revealed that the air masses over Zibo on haze days mainly originated in adjacent areas in Shandong Province and the Beijing-Tianjin-Hebei region (BTH). The haze episode was caused by a combination of unfavorable meteorological conditions, secondary formation, the accumulation of local pollutants, and peripheral transmission.

The characteristics of heavy metal pollution in surface dust in Tangshan, a heavily industrialized city in North China, and an assessment of associated health risks

With the rapid development of industrialization and urbanization, surface dust has an increasing impact on people’s living environment and human health. Tangshan is an important heavily industrialized city in North China. To understand the heavy metal pollution associated with surface dust in Tangshan City, and its health risks, a total of 162 surface dust samples were collected in the central downtown area of Tangshan City. The concentrations of eight heavy metals were measured (As, Cd, Hg, Pb, Cr, Cu, Zn, and Ni). The results indicate that the heavy metals show different degrees of enrichment. As, Hg, Cr, and Ni in surface dust are mainly sourced from fuel coal and industrial production activities, while Zn and Cu are mostly sourced from metal smelting and urban transportation. Pb is associated with urban transportation, and Cd is associated with industrial activities such as metal smelting, and urban transportation. The pollution levels of As, Cr, Cu, and Ni in surface dust range from the non-pollution to moderate pollution classifications, while Hg and Pb are classified as moderate pollution, Zn ranges from moderate pollution to strong pollution, and Cd concentrations are classified as strong pollution. The total ecological risk level of surface dust is very high, with a high ecological risk posed by Cd, a very strong ecological risk posed by Hg, and slight ecological risks posed by As, Cr, Pb, Zn, Cu, and Ni. The total non-carcinogenic risk (HI) for children and adults is ranked As > Pb > Cr > Cd > Zn > Ni > Cu > Hg. The HI of children through different exposure pathways is higher than that for adults. Hand–mouth intake is the largest contributor to the HI. The HI of children for hand–mouth intake is higher than adults. Ni, Cr, As, and Cd in surface dust do not pose a carcinogenic risk through respiration pathways.

Mixing layer height estimated from AMDAR and its relationship with PMs and meteorological parameters in two cities in North China during 2014–2017

The mixing layer height (MLH) plays an important role in atmospheric pollution by influencing the vertical diffusion of pollutants. The Aircraft Meteorological Data Relay (AMDAR) from the airports in Beijing (BJ) and Shijiazhuang (SJZ) during 2014–2017 was used to investigate temporal characteristics of the daily maximum MLH (MLHmax) and their relationships with surface meteorological parameters and particulate matters (PM1, PM2.5, and PM10).The seasonal mean of MLHmax in BJ was higher than that of SJZ, and shows the seasonal variation trend of summer> spring >autumn > winter in both cities. The MLHmax was found to have a positive correlation with daily average wind speed at 2 m (WS) in all seasons except summer and a significant negative correlation with daily average relative humidity at 2 m (RH) in four seasons. These implied a high risk of air pollution during low-MLHmax period. Subsequently, a higher negative relationship between MLHmax and PMs was obtained in both cities in autumn and winter based on the polynomial regression method, with a coefficient of determination (R2) of 0.37–0.71 in autumn and 0.52–0.88 in winter. In BJ, the sequence of R2 was PM1 >PM2.5 >PM10, yet a total opposite trend was observed in SJZ. It illustrated that the greatest contribution to local emissions in BJ and SJZ is PM1 and PM10 respectively, which means that the impact of MLHmax to local emissions and the secondary formed pollutants is stronger than that of long range transport. The ammoniate (NH4+), nitrate (NO3−) and sulfate (SO42−) also performed a better correlation with MLHmax than elemental carbon (EC) and organic carbon (OC) in BJ; while in SJZ, a better correlation between MLHmax and EC is easy to be found, while NO3− and SO42− performed a worse correlation with it. Therefore, PM pollution was characterized by secondary formation in BJ but by primary emissions in SJZ.

An integrated assessment of China's South—North Water Transfer Project

AbstractChina's South–North Water Transfer Project (SNWTP) is a vast and still expanding network of infrastructure and institutions that moves water from the Yangtze River and its tributaries to cities in North China. This article aims to assess the SNWTP's impacts by beginning to answer seven questions about the project: How is the management of the SNWTP evolving? What are the problems to be resolved when managing SNWTP water within jurisdictions? What are the status and management of water quality in the SNWTP? What are the consequences of resettlements caused by the SNWTP? How is increased water supply affecting regional development? Is the SNWTP achieving its stated environmental goals? What are the sustainability credentials of the SNWTP? Drawing on primary and secondary data, the article demonstrates both that the opportunities and burdens characterising the project are highly uneven and that management systems are evolving rapidly in an attempt to enforce strict water quality targets. Furthermore, while the SNWTP may be helping to resolve groundwater overexploitation in Beijing, it is highly energy intensive, raising questions about its sustainability. Our analysis highlights the need to continue to interrogate the socio‐economic, environmental, and political implications of such schemes long after they are officially completed.

City Profile: Datong, China

Small- and medium-sized cities have not received enough scholarly attention in China. In fact, these cities have a larger share of urban population than large-sized cities. Therefore, the paper focuses on one such typical medium-sized city in North China named Datong; a resource-reliant city with a long history but undergoing a difficult phase of transformation. Its industrial structure is upgrading from unitary resource-dependence to balanced development, but it is also accompanied by recessive unemployment and a depressed consumption pattern of its residents. Datong’s urban planning generally reflects the ideas of its leaders and often demonstrates high efficiency and execution. However, abrupt change in the leadership has brought new challenges such as constant adjustment and restructuring along with huge investment and financial risks to cities. This model also fully illustrates the self-repairing and error-correcting ability, which is guiding Datong towards sustainable development.

Investigation and low energy improvement of the thermal environment of work areas in the Qingdao Metro in winter

Few studies have investigated the thermal environment of the work area hall in underground metro stations during winter. Two underground stations were chosen within Qingdao Metro Lines 2 and 3 to investigate the thermal environment in the work area hall in northern city metros in China. Air temperatures and wind velocity parameters were identified as key influencing factors and were continuously measured in the work area. The study found that the thermal environment fluctuates frequently in the work area throughout the day. Changes in temperatures and wind speeds were periodically caused by piston wind flowing from the platform level. To improve this heating situation in the work area in winter, the study proposes recycling waste heat from the power equipment rooms, using the air source but through the water cycle heat pump system. Insights from the study may help save energy and improve the thermal environment, and could be applied across metro stations in north China cities in winter. Practical application: The thermal comfort of the working area in the metro station hall is extremely poor as indicated by a study of Qingdao Metro stations. This paper explores the application of a heat pump as a means of heating the working area to improve the cold and damp winter environment for the metro staff using waste heat from the machine rooms.

Dynamic simulation of the optimal allocation of water resources via the introduction of integrated water environmental policies in Baoding, China.

With rapid industrialization and urbanization, regional water shortages and water quality deterioration have posed great challenges for the sustainable development of cities in North China, especially those with a large demand for agricultural irrigation water. Based on an input-output analysis, this paper develops a dynamic optimization model consisting of three sub-models and multiple constraint conditions to solve the water crisis of Baoding, a typical city experiencing water shortages and serious water pollution in North China. The water resource carrying capacity (WRCC) indicator is introduced in the analysis of the results to comprehensively assess the effect of integrated water environmental policies (IWEPs) from 2013 to 2025. In the optimal scenario, the annual chemical oxygen demand (COD) discharge and annual water demand in Baoding can be reduced by 2.6% and 0.6%, respectively, with an annual gross regional product (GRP) growth rate of 7.52%. The WRCC can be improved from moderately overloaded to weakly unsaturated, which indicates that water resources can meet the socioeconomic development requirements. The results demonstrate the effectiveness of the linear optimization model with input-output analysis in coordinating the relationships among water demand, water environment protection, and economic development, and the IWEPs provide an applicable reference for decision-makers in Baoding and other similar cities in North China to address deteriorating water systems.

The effect and burden modification of heating on adult asthma hospitalizations in Shijiazhuang: a time-series analysis

BackgroundPrevious studies have found associations between asthma morbidity and air pollution especially in young population, (PLoS One 12:e0180522, 2017; Can J Public Health 103:4-8, 2012; Environ Health Perspect 118:449-57, 2010; Am J Respir Crit Care Med 182:307-16, 2010; J Allergy Clin Immunol 104:717-22, 2008; J Allergy Clin Immunol 104:717-22, 1999; Environ Res 111:1137-47, 2011) but most of them were conducted in areas with relatively low air pollutant level. Moreover, very few studies have investigated the effect and burden modification of heating season during which the ambient air pollution level is significantly different from that during non-heating season in north China.ObjectivesThis study aimed to evaluate the effect and burden modification of heating on short-term associations between adult asthma hospitalizations and ambient air pollution in the north China city of Shijiazhuang.MethodsGeneralized additive models combined with penalized distributed lag nonlinear models were used to model associations between daily asthma hospitalizations and ambient air pollutants from 1 January 2013 to 16 December 2016 in Shijiazhuang city, adjusting for long-term and seasonality trend, day of week, statutory holiday, daily mean air pressure and temperature. Attributable risks were calculated to evaluate the burden of asthma hospitalizations due to air pollutants exposure. The effect of pollutants on hospitalization and the attributable measures were estimated in heating and non-heating season separately and the comparisons between the two seasons were conducted.ResultsAll pollutants demonstrated positive and significant impacts on asthma hospitalizations both in heating season and non-heating season, except for O3 in heating season where a negative association was observed. However, the differences of the pollutant-specific effects between the two seasons were not significant. SO2 and NO2 exposure were associated with the heaviest burden among all pollutants in heating season; meanwhile, PM10 and PM2.5 were associated with the heaviest burden in heating season.ConclusionsIn conclusion, we found evidence of the effect of ambient air pollutants on asthma hospitalizations in Shijiazhuang. The central heating period could modify the effects in terms of attributable risks. The disease burden modification of heating should be taken into consideration when planning intervention measures to reduce the risk of asthma hospitalization.

Coupling and metabolic analysis of urbanization and environment between two resource-based cities in North China.

BackgroundThe complex relationship between urbanization and environment in resource-based cities is of increasing concern.MethodsAs typical examples of rapid economic growth, obvious urbanization, and successful transformed production models, the cities of Dongying and Binzhou in Yellow River Delta High-tech Economic Zone were chosen for research. First, this study examines the coupling relationship between urbanization and the environment over the last seventeen years using the coupling degree model. Second, the emergy analysis method is used to further study the energy metabolism and environmental load in the two cities to reveal these couplings.ResultsDongying and Binzhou were well-coupled and the coupling coordination degree was in the stage of mild coordination coupling showing an upward trend. The total metabolic energy of the two cities increased yearly from 2000 to 2016, and the emergy extroversion ratio data showed the cities’ dependence on external elements such as continuously increased imported resources. The total emergy used in the two cities showed an upward trend during 2000 and 2016, while the emergy per capita consumption increased significantly, suggesting that the society’s energy efficiency improved. During the same period, the environmental loading ratio increased gradually, and the elements causing the environmental load shifted from internal to external.DiscussionThe study shows that the factors of environmental load in developing cities are gradually shifting from internal to external, which is vital to understanding the impact of urban transformation and upgrading of resource-based cities on the environment.

Primary emissions versus secondary formation of fine particulate matter in the most polluted city (Shijiazhuang) in North China

Abstract. Particulate matter (PM) pollution is a severe environmental problem in the Beijing–Tianjin–Hebei (BTH) region in North China. PM studies have been conducted extensively in Beijing, but the chemical composition, sources, and atmospheric processes of PM are still relatively less known in nearby Tianjin and Hebei. In this study, fine PM in urban Shijiazhuang (the capital of Hebei Province) was characterized using an Aerodyne quadrupole aerosol chemical speciation monitor (Q-ACSM) from 11 January to 18 February in 2014. The average mass concentration of non-refractory submicron PM (diameter &lt;1 µm, NR-PM1) was 178±101 µg m−3, and it was composed of 50 % organic aerosol (OA), 21 % sulfate, 12 % nitrate, 11 % ammonium, and 6 % chloride. Using the multilinear engine (ME-2) receptor model, five OA sources were identified and quantified, including hydrocarbon-like OA from vehicle emissions (HOA, 13 %), cooking OA (COA, 16 %), biomass burning OA (BBOA, 17 %), coal combustion OA (CCOA, 27 %), and oxygenated OA (OOA, 27 %). We found that secondary formation contributed substantially to PM in episodic events, whereas primary emissions were dominant (most significant) on average. The episodic events with the highest NR-PM1 mass range of 300–360 µg m−3 were comprised of 55 % of secondary species. On the contrary, a campaign-average low OOA fraction (27 %) in OA indicated the importance of primary emissions, and a low sulfur oxidation degree (FSO4) of 0.18 even at RH &gt;90 % hinted at insufficient oxidation. These results suggested that in Shijiazhuang in wintertime fine PM was mostly from primary emissions without sufficient atmospheric aging, indicating opportunities for air quality improvement by mitigating direct emissions. In addition, secondary inorganic and organic (OOA) species dominated in pollution events with high-RH conditions, most likely due to enhanced aqueous-phase chemistry, whereas primary organic aerosol (POA) dominated in pollution events with low-RH and stagnant conditions. These results also highlighted the importance of meteorological conditions for PM pollution in this highly polluted city in North China.

Assessment of the water resource carrying capacity based on the ecological footprint: a case study in Zhangjiakou City, North China.

With the rapid economic development in the past decades, industrialization and urbanization in China has also rapidly developed and will continue in the next decades. However, the regional water shortage has posed great challenges for the sustainable development of big cities especially in north China. Here, we used the water ecological footprint model combined with the system dynamic model to assess the water resource carrying capacity and its sustainability in Zhangjiakou City, a typical water shortage city in north China. The calculated results showed that irrigation was the largest water consumer in Zhangjiakou. There existed a clear gap between water supply and water consumption in this city and such a gap is demonstrated by the high water resource pressure index. Our predicted results based on the water resource ecological footprint and the system dynamic model showed that although the improving water use efficiency has relieved the regional water shortage pressure, the efficiency gained would be to a large degree offset by increased water demands due to the increasing economic development. The annual average water shortage in Zhangjiakou in 2007-2050 would be up to 8.53 × 108m3, nearly half of the total local average annual water resource. To deal with the severe water shortage over the next three decades, great attention should be paid to scientific water resource managements and water pollution control. This research provides a long-term view of water resource pressure and provides recommendations for a sustainable water use under the rapid regional socioeconomic development.

Spatial Data Assisted Ground Source Heat Pump Potential Analysis in China, a Case of Qingdao City

Nowadays, China faces challenges of further implementing heat pump technology for meeting building heating and cooling demand. The utilization of heat pumps, especially ground source heat pump (GSHP) is associated with a number of geological, hydrological as well as meteorological criteria. Thus it is essential to systematically address the feasibility of ground source heat pumps application using quantitative evaluation. Spatial data analysis is a method widely used in energy field to investigate renewable energy potential. Therefore, this study strives to provide an estimation of electricity driven GSHP’s potential in north China using spatial data assisted tools. Followed by a case study using the methodology recommended, a spatial data assisted GSHP potential evaluation model is built for Qingdao city in north China. The evaluation model is constructed and analyzed through spatial data processing software visualized by ground source heat pump potential maps. The result maps show that, places with most potential of GSHP application locate in south Qingdao close to the sea. Such places have a higher ground extractable heat and relatively low drilling cost.

Near Full-Length Genome Sequence of a Novel HIV-1 Second-Generation Recombinant Form (CRF01_AE/CRF07_BC) Detected Among Men Who Have Sex with Men in Tianjin, China.

In recent years, men who have sex with men (MSM) have been the most affected population with fastest growing human immunodeficiency virus (HIV) prevalence in China. In our study, a novel CRF01_AE/07_BC HIV-1 recombinant form (TJIH0069), with four unique breakpoints in the pol, vpr, and nef gene regions, was identified among MSM in Tianjin City in north China. The CRF01_AE regions (regions I, III, and V) of the recombinant are all clustered together with a previously described sequence (HQ215555), which was exclusively circulating among MSM in Shijiazhuang city of Hebei Province in north China. The CRF07_BC regions (II and IV) are clustered with BJ070032 and JX960600, which were discovered from MSM population in north China. The continuous emergence of a similar pattern of recombinant strain between the two MSM-adapted existing circulating recombinant forms (CRFs) highlights the importance to monitor potential new CRFs for early and precise control and prevention.

Reflection of concentrations of polybrominated diphenyl ethers in health risk assessment: A case study in sediments from the metropolitan river, North China

As a developed city in North China, Tsingtao is believed to be suffering from the pollution of polybrominated diphenyl ethers (PBDEs) due to the rapid industrialization and urbanization in recent years. In this work, 8 PBDE congeners were detected in sediments from Moshui River, Tsingtao. BDE-209 and sum of 7 low brominated PBDE congeners (∑7PBDEs, excluding BDE-209) ranged from 10.2 × 10−3 to 237 × 10−3 mg kg−1 and from 1.62 × 10−3 to 23.1 × 10−3 mg kg−1 d.w., respectively. PBDE concentrations decreased in the order of midstream > downstream > upstream, attributing to the discrepancies in anthropogenic activities among these areas. Principal component analysis coupled with multiple linear regression (PCA-MLR) revealed that 24.4% of PBDEs were derived from surface runoff of contaminated soils, 58.2% from direct discharge of local sources and 17.4% from atmospheric deposition. The probabilistic health risk assessment of PBDEs was performed by using Monte Carlo simulation. The carcinogenic and non-carcinogenic risks based on total PBDEs were low for children and teens, whilst severe for adults. However, based on bioaccessible PBDEs (in vitro gastrointestinal model), there was no obvious health risk for the three age groups. To the best of our knowledge, the present study was the first attempt to assess the health risk by using bioaccessible PBDEs in sediments.