Seasonal Growth of Waterhyacinth in the Sacramento/San Joaquin Delta, California

Waterhyacinth ( Eichhornia crassipes (Mart.) Solms), is a serious problem in the Sacramento/San Joaquin Delta, California. There is little published information on its phenology or seasonal growth in this system. Waterhyacinths were sampled at 2 to 3 week intervals from November, 1995 to July, 1997 and the following measurements were made on individual plants: dry weight, height, number of living leaves, number of dead leaves, and the width of the largest lamina. (PDF has 4 pages.

Estimating the cost-effectiveness of fluticasone propionate for treating chronic obstructive pulmonary disease in the presence of missing data

Objectives: To explore the cost-effectiveness of fluticasone propionate (FP) for the treatment of chronic obstructive pulmonary disease (COPD), we estimated costs and qualityadjusted life-years (QALYs) over 3 years, based on an economic appraisal of a previously reported clinical trial (Inhaled Steroids in Obstructive Lung Disease in Europe [ISOLDE]). Methods: Seven hundred forty-two patients enrolled in the ISOLDE trial who received either FP or placebo had data available on health-care costs and quality of life over the period of the study. The SF-36-based utility scores for quality of life were used to calculate QALYs. A combined imputation and bootstrapping procedure was employed to handle missing data and to estimate statistical uncertainty in the estimated cumulative costs and QALYs over the study period. The imputation approach was based on propensity scoring and nesting this approach within the bootstrap ensured that multiple imputations were performed such that statistical estimates included imputation uncertainty. Results: Complete data were available on mortality within the follow-up period of the study and a nonsignificant trend toward improved survival of 0.06 (95% confidence interval [CI] –0.01 to 0.15) life-years was observed. In an analysis based on a propensity scoring approach to missing data we estimated the incremental costs of FP versus placebo to be £1021 (95% CI £619–1338) with an additional effect of 0.11 QALYs (CI 0.04–0.20). Cost-effectiveness estimates for the within-trial period of £17,700 per life-year gained (£6900 to ∞) and £9500 per QALY gained (CI £4300–26,500) were generated that include uncertainty due to the imputation process. An alternative imputation approach did not materially affect these estimates. Conclusions: Previous analyses of the ISOLDE study showed significant improvement on disease-specific health status measures and a trend toward a survival advantage for treatment with FP. This analysis shows that joint considerations of quality of life and survival result in a substantial increase in QALYs favoring treatment with FP. Based on these data, the inhaled corticosteroid FP appears costeffective for the treatment of COPD. Confirmation or refutation of this result may be achieved once the Towards a Revolution in COPD Health (TORCH) study reports, a large randomized controlled trial powered to detect mortality changes associated with the use of FP alone, or in combination with salmeterol, which is also collecting resource use and utility data suitable for estimating cost-effectiveness

Do tissue carbon and nitrogen limit population growth of weevils introduced to control waterhyacinth at a site in the Sacramento-San Joaquin Delta, California?

Waterhyacinth (Eichhornia crassipes(Mart.) Solms), is a serious problem in the Sacramento Delta. Two weevil species (Neochetina bruchi Hustache and N. eichhorniae Warner) have been introduced as biological control agents. The purpose of this study was to test the hypothesis that nitrogen (N) in the tissue of waterhyacinth was not sufficient to support weevil growth and reproduction. Because it grows better on plants with high N content and because it has a greater impact on the growth of high N plants, N. bruchi may be a more effective biological control agent in the Sacramento Delta

The Private Cost of Long-Term Care in Canada: Where You Live Matters

Canadians expect the same access to health care whether they are rich or poor, and wherever they live, often without direct charge at the point of service. However, we find that the private cost of long-term care differs greatly across the country, and within provinces, we find substantial variation, depending on income level, marital status, and, in Quebec alone, on assets owned. A non-married person with average income would pay more than twice as much in the Atlantic provinces as in Quebec, while a couple with one in care would pay almost four times as much in Newfoundland as in Alberta.long-term care , private cost