A Checklist of River Function Indicators for hydropower ecological assessment.

Hydropower generation has advantages for societies that seek low-carbon, renewable energy alternatives, but sustainable hydropower production will require an explicit consideration of potential tradeoffs between socioeconomic and environmental priorities. These tradeoffs are often explored during a formal environmental impact assessment process that can be complex and controversial. The steps taken to address stakeholder concerns through impact hypotheses and field studies are not always transparent.

Paleoenvironmental history of the West Baray, Angkor (Cambodia).

Angkor (Cambodia) was the seat of the Khmer Empire from the 9th to 15th century AD. The site is noted for its monumental architecture and complex hydro-engineering systems, comprised of canals, moats, embankments, and large reservoirs, known as barays. We infer a 1,000-y, (14)C-dated paleoenvironmental record from study of an approximately 2-m sediment core taken in the largest Khmer reservoir, the West Baray.

Global search for minimum energy (H2O)n clusters, n = 3-5.

The Gaussian-3 (G3) model chemistry method has been used to calculate the relative deltaG(o) values for all possible conformers of neutral clusters of water, (H2O)n, where n = 3-5. A complete 12-fold conformational search around each hydrogen bond produced 144, 1728, and 20,736 initial starting structures of the water trimer, tetramer, and pentamer. These structures were optimized with PM3, followed by HF/6-31G* optimization, and then with the G3 model chemistry.