The purpose of this study was to verify a Chinese version of Community of Inquiry (CoI) instrument with learning presence and explore the causal relationships of the factors in the instrument. This study first examined the reliability and validity of the instrument. All four presences had acceptable levels of reliability (all Cronbach's α> .765 or higher). The confirmatory factor modeling approach was used to assess its validity. Then, the study used path analysis and regression analysis to explore the causal relationships of the presences. The key findings showed that teaching and social presences directly influenced the perceptions of learning presence. Learning presence was a partial mediating variable of interactional relationship within CoI constructs.

Based on the datum line survey in August 2005 and June and August of 2006, water samples were collected in 30 sites to examine the trend of spatial distribution and temporal change of dissolved metals in seawater of Jinzhou Bay, China. The results showed that copper (Cu), lead (Pb), zinc (Zn), and cadmium (Cd) concentrations ranged from 1.71 to 3.49, 0.38 to 1.19, 21.77 to 39.16, and 1.65 to 2.01 microg/L, respectively. Except for Zn, the dissolved metal concentrations in August 2006 were much higher than those in August 2005. The concentrations in June 2006 were also higher than those in August 2006. The highest concentrations of dissolved metal were determined in samples collected from southwest of the Bay near sewage outfalls of Huludao Zinc Plant and Bohai Shipyard and the mouths of Wuli and Cishan rivers. The concentrations of dissolved metals increased inshore as compared with offshore. The principal contaminated factors were Zn, Cd, and Pb in the Jinzhou Bay. Significant positive correlations existed between the concentrations of Cu and Cd (0.016), as well as Zn and Cd (0.000). The overall results revealed that the Bohai Sea was one of the most contaminated areas by dissolved metals compared to other coastal areas in China.

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