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Water quality degradation is often a severe consequence of rapid economic expansion in developing countries. Methods to assess spatial-temporal patterns and trends in water quality are essential for guiding adaptive management efforts aimed at water quality remediation. Temporal and spatial patterns of surface water quality were investigated for 54 monitoring sites in the Wen-Rui Tang River watershed of eastern China to identify such patterns in water quality occurring across a rural-suburban-urban interface. Twenty physical and chemical water quality parameters were analyzed in surface waters collected once every 4-8 weeks from 2000 to 2010. Temporal and spatial variations among water quality parameters were assessed between seasons (wet/dry) and among major land use zones (urban/suburban/rural). Factor analysis was used to identify parameters that were important in assessing seasonal and spatial variations in water quality. Results revealed that parameters related to organic pollutants (dissolved oxygen (DO), chemical oxygen demand (manganese) (COD Mn ), and 5-day biochemical oxygen demand (BOD 5 )), nutrients (ammonia nitrogen (NH 4 + -N), total nitrogen (TN), total phosphorus (TP)), and salt concentration (electrical conductivity (EC)) were the most important parameters contributing to water quality variation. Collectively, they explained 70.9 % of the total variance. A trend study using the seasonal Kendall test revealed reductions in COD Mn , BOD 5 , NH 4 + -N, petrol, V-phen, and EC concentrations over the 11-year study period. Cluster analysis was employed to evaluate variation among 14 sampling sites representative of dominant land use categories and indicated three, three, and four clusters based on organic, nutrient, and salt water quality characteristics, respectively. Factors that are typically responsible for water quality degradation (including population, topography, and land use) showed no strong correlation with water quality trends implying considerable point source inputs in the watershed. The results of this study help inform ongoing water quality remediation efforts by documenting trends in water quality across various land use zones.

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Central nervous system infection and AEDs withdrawal in epilepsy patients were the most important causes of CSE. There is a large gap between antiepileptic therapy in China and European Status Epilepticus guidelines.

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Constraining which nutrients limit phytoplankton growth is important for understanding ocean productivity, its response to climate change, and providing a benchmark on the accuracy of ocean biogeochemical models. The extensive subtropical Northwest Pacific is assumed to be nitrogen limited, but this is based mostly on indirect evidence. We conducted experiments along an~8000 km cruise track showing a geographic switch from sites that were nitrogen limited and those that were nitrogen-iron co-limited. Co-limited sites showed much larger responses to nutrient supply, due to blooming of diatoms that were initially undetectable. Because diatom growth leads to higher biomass accumulation and more efficient energy transfer up food chains, we hypothesize that this gradient could be important for regulating matching gradients in predatory tuna.

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