The purpose of this study was to determine whether Zn is involved in endoplasmic reticulum (ER) stress inhibition-induced cardioprotection against ischemia/reperfusion (I/R) injury by modulation of the mitochondrial permeability transition pore (mPTP) opening. Isolated rat hearts were subjected to 30-min regional ischemia followed by 2 h of reperfusion. Expression of glucose regulated protein 78 (GRP 78 or BIP), an ER homeostasis marker, was not increased during ischemia but was increased upon reperfusion, indicating that ER stress was initiated upon reperfusion but not during ischemia. The ER stress inhibitor tauroursodeoxycholic acid (TUDCA) given at reperfusion resulted in a significant reduction of GRP78 expression 30 and 60 min after the onset of reperfusion, an effect that was reversed by the zinc chelator N,N,N',N'-tetrakis-(2-pyridylmethyl) ethylenediamine (TPEN). The immunofluorescence study also showed that the effect of TUDCA on GRP78 expression was reversed by TPEN. TUDCA reduced infarct size and this was reversed by the mPTP opener atractyloside, indicating that ER stress inhibition may induce cardioprotection by modulating the mPTP opening. Experiments with transmission electron microscopy and hematoxylin-eosin staining also revealed that TUDCA prevented endoplasmic reticulum and mitochondrial damages at reperfusion, which was blocked by TPEN. Exposure of cardiac H9c2 cells to HO increased GRP 78 and GRP 94 expressions, suggesting that oxidative stress can induce ER stress. Cells treated with HO showed a significant decrease in tetramethylrhodamine ethyl ester (TMRE) fluorescence, indicating that HO triggers the mPTP opening. In contrast, TUDCA prevented the loss of TMRE fluorescence, the effect that was blocked by TPEN, indicating a role of Zn in the preventive effect of ER stress inhibition on the mPTP opening. In support, TUDCA significantly increased intracellular free zinc. These data suggest that reperfusion but not ischemia initiates ER stress and inhibition of ER stress protects the heart from reperfusion injury through prevention of the mPTP opening. Increased intracellular free Zn accounts for the cardioprotective effect of ER stress inhibition.

The aim of the study is to identify long-range transport pathways that may have an important influence on PM 10 levels in plateau uplift area, namely Xining in northwestern China. Cluster analysis was applied to identify the main trajectory groups in horizontal direction and 3D cluster analysis was employed to identify the origins and distributions of major trajectory groups in vertical direction. Potential Source Contribution Function (PSCF) and Concentration-weighted Trajectory (CWT) were applied to identify the major potential source areas (PSA). Based on the temporal and spatial distribution of backward trajectories, four major trajectory pathways were clustered. The results indicated that Xining was easily affected by inland trajectories in four seasons but there were obvious results that different trajectories have dissimilar influences on the mean PM 10 concentrations. In horizontal direction, the long-range transport pathways were obvious in spring and winter while a few of long-range transport pathways could be found in summer and autumn. Because wind mainly came from north or west in spring and winter and it was very strong, which had a big influence on the transportation of transport pathways while wind in summer and autumn had a small impact on the transportation of transport pathways. In vertical direction, in the 700 hPa barometric altitude (3000 m) above, air masses in winter and spring with long transport pathways were the most important back-trajectories which had a great influence on Xining city. In summer and autumn, Xining was mainly influenced by airflow distributed below 700 hPa barometric altitude. In spring and winter, eastern Xinjiang, border areas between Gansu and Inner Mongolia and southern Tibet in China with the highest Weight Potential Source Contribution Function (WPSCF) and Weight Concentration-weighted Trajectory (WCWT) values were the dominant potential sources, which demonstrated the contribution from sources outside of Xining were significant. In summer and autumn, WPSCF values outside of Xining were no more than 0.5 (most of them were less than 0.3) and WCWT values were almost lower than 100 µg m -3 in those two seasons, which suggested that there were no main important PSA in those two seasons. Furthermore, the study also revealed that Tibet in China was one of the potential sources of PM 10 in Xining.

Coastal regions experience both terrestrial anthropogenic emissions and marine sources. Due to considerable human activities and special weather patterns (regular monsoon and sea-land breeze), this region is subjected to complex air pollution (

Abstract. Ammonia in the atmosphere is essential for the formation of fine particles that impact air quality and climate. Despite extensive prior research to disentangle the relationship between ammonia and haze pollution, the role of ammonia in haze formation in high ammonia-emitting regions is still not well understood. Aiming to better understand secondary inorganic aerosol (sulfate, nitrate, ammonium – SNA) formation mechanisms under high-ammonia conditions, 1-year hourly measurement of water-soluble inorganic species (gas and particle) was conducted at a rural supersite in Shanghai. Exceedingly high levels of agricultural ammonia, constantly around 30 µg m−3, were observed. We find that gas-particle partitioning of ammonia (ε(NH4+)), as opposed to ammonia concentrations, plays a critical role in SNA formation during the haze period. From an assessment of the effects of various parameters, including temperature (T), aerosol water content (AWC), aerosol pH, and activity coefficient, it seems that AWC plays predominant regulating roles for ε(NH4+). We propose a self-amplifying feedback mechanism associated with ε(NH4+) for the formation of SNA, which is consistent with diurnal variations in ε(NH4+), AWC, and SNA. Our results imply that a reduction in ammonia emissions alone may not reduce SNA effectively, at least at rural agricultural sites in China.

This paper focuses on a conventional debate regarding whether Chinese outward direct investors tend to invest in countries with high political risk. Using 2003 -2011 data from the World Bank, the Heritage Foundation and the KOF Swiss Economic Institute, we investigate China's political risk distribution and political risk index (PRI). Our results indicate that China's political risk index was ranked 48th among 153 economies in 2011, in the lower risk level of the PRI spectrum. In an international comparison of political risk distribution, the proportion of Chinese outward direct investment (ODI) among countries with high political risk is less than the world average. The Chinese ODI political risk index has significantly improved and remains lower than the world average. To improve Chinese ODI PRI, the Chinese Government should continue to implement differentiation strategies and to offer official development assistance to improve the investment environment in developing countries and reduce political risk.

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Using principal component analyses, this paper constructs two internationalization indicesfor the renminbi (RMB) and 32 other major currencies. We find that the RMB's currency internationalization degree index (CIDI) is still low, and far behind the 4 most important international currencies. In 2009, it was ranked 18th among all important international currencies. However, in terms of the currency internationalization prospect index (CIPI), the RMB has remained the world's fifth highest since 2006. Although it is still far behind the US dollar and the euro, surpassing the ranking of the yen and the pound is possible in the near future. The dramatic difference in the ranking between the CIDI and the CIPI is a result of China's tight capital account control, the usage continuity of international currency due to network externalities, and the narrow foreign exchange and imperfect financial markets. Hence, to a large degree, the RMB's potential as an international currency depends on China's capital account liberalization.

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