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Since 1995, the National Stream Quality Accounting Network (NASQAN) of the U. S. Geological Survey (USGS) has focused on monitoring the water quality of the Nation's largest rivers including the Colorado, Columbia, Mississippi, and Rio Grande. The NASQAN program in the Colorado River Basin consists of eight stations that span seven basin States including Colorado, Wyoming, Utah, New Mexico, Arizona, Nevada, and California. Data collected from these stations are used to quantify the transport of chemical constituents and evaluate trends in water quality of the river. Currently, the NASQAN program in the Colorado River Basin is providing necessary data and information required by resource managers of the river who are responsible for meeting longstanding legal agreements that regulate the flow and quality of the river water. The Colorado River often is described as the most controversial and regulated river in the United States. The river currently provides 25 million people with drinking water and also provides enough water to keep 3.5 million acres of farmland in production. Other uses include industrial, recreation, and electric-power generation. The river is highly regulated with 83 reservoirs in the upper basin and 10 reservoirs in the lower basin that are capable of storing 4 years of flow. Twelve legal agreements, compacts, contracts, and State and Federal legislation apportion and regulate the use, management, and quality of water for the Colorado River water among the seven States in the basin and Mexico (Newcom, 1998). The Colorado River drains about 250,000 square miles. Annual flows in the river fluctuated greatly before the big dams were built on the river because of winter snowmelt and summer thunderstorms. Water, sediment, and chemical transport from the upper basin are greatest in June. Daily fluctuations in the lower basin are caused by irrigation and water-supply diversions, power generation, losses to evaporation and transpiration from riparian vegetation, and irrigation return flows.

The ability to discover and integrate data from multiple sources, projects, and research efforts is critical as scientists continue to investigate complex hydrologic processes at expanding spatial and temporal scales. Until recently, syntactic and semantic heterogeneity in data from different sources made data discovery and integration difficult. The Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI) Hydrologic Information System (HIS) was developed to improve access to hydrologic data. A major semantic challenge related to data sharing and publication arose in development of the HIS. No accepted vocabulary existed within the hydrology research community for describing hydrologic observations, making it difficult to discover and synthesize data from multiple research groups even if access to the data was not a barrier. Additionally, the hydrology research community relies heavily on data collected or assembled by government agencies such as USGS and USEPA, each of which has its own semantics for describing observations. This semantic heterogeneity across data sources was a challenge in developing tools that support data discovery and access across multiple hydrologic data sources by time, geographic region, measured variable, data collection method, etc. This paper describes a community shared vocabulary and its supporting management tools that can be used by data publishers to populate metadata describing hydrologic observations to ensure that data from multiple sources published within the CUAHSI HIS are semantically consistent. We also describe how the CUAHSI HIS mediates across terms in the community shared vocabulary and terms used by government agencies to support discovery and integration of datasets published by both academic researchers and government agencies.

To access publisher full text version of this article. Please click on the hyperlink in Additional Links field. ; Chronic obstructive pulmonary disease (COPD) is predicted to become the third most common cause of death and disability worldwide by 2020. The prevalence of COPD defined by the lower limit of normal was estimated using high-quality spirometry in surveys of 14 populations aged ≥ 40 yrs. The strength and consistency of associations were assessed using random effects meta-analysis. Pack-years of smoking were associated with risk of COPD at each site. After adjusting for this effect, we still observed significant associations of COPD risk with age (OR 1.52 for a 10 yr age difference, 95% CI 1.35-1.71), body mass index in obese compared with normal weight (OR 0.50, 95% CI 0.37-0.67), level of education completed (OR 0.76, 95% CI 0.67-0.87), hospitalisation with a respiratory problem before age 10 yrs (OR 2.35, 95% CI 1.42-3.91), passive cigarette smoke exposure (OR 1.24, 95% CI 1.05-1.47), tuberculosis (OR 1.78, 95%CI 1.17-2.72) and a family history of COPD (OR 1.50, 95% CI 1.19-1.90). Although smoking is the most important risk factor for COPD, other risk factors are also important. More research is required to elucidate relevant risk factors in low- and middle-income countries where the greatest impact of COPD will occur. ; ALTANA Aventis AstraZeneca Boehringer-Ingelheim Chiesi GlaxoSmithKline Merck Novartis Pfizer Schering-Plough Sepracor University of Kentucky Boehringer Ingelheim China (Guangzhou, China) Turkish Thoracic Society Pfizer (Adana, Turkey) Merck Sharpe Dohme Salzburger Gebietskrankenkasse Salzburg Local Government (Salzburg, Austria) Research for International Tobacco Control International Development Research Centre South African Medical Research Council South African Thoracic Society GlaxoSmithKline University of Cape Town Lung Institute (Cape Town, South Africa) Landspitali-University Hospital GlaxoSmithKline Iceland AstraZeneca Iceland (Reykjavik, Iceland) GlaxoSmithKline ...