Multidecadal declines in particulate mercury and sediment export from Russian rivers in the pan-Arctic basin.

SignificanceRussian rivers are the predominant source of riverine mercury to the Arctic Ocean, where methylmercury biomagnifies to high levels in food webs. Pollution controls are thought to have decreased late-20th-century mercury loading to Arctic watersheds, but there are no published long-term observations on mercury in Russian rivers. Here, we present a unique hydrochemistry dataset to determine trends in Russian river particulate mercury concentrations and fluxes in recent decades. Using hydrologic and mercury deposition modeling together with multivariate time series analysis, we determine that 70 to 90% declines in particulate mercury fluxes were driven by pollution reductions and sedimentation in reservoirs. Results suggest that Russian rivers likely dominated over all other sources of mercury to the Arctic Ocean until recently.

Description of local carbon flux from large scale gridded climate data by a dynamic global vegetation model at variable time steps: Example of Euroflux sites.

Dynamic Global Vegetation Models (DGVMs) are commonly used to describe the land biogeochemical processes and regulate carbon and water pools. However, the simulation efficiency and validation of DGVMs are limited to varying temporal and spatial resolutions. Additionally, the uncertainties caused by different interpolation methods used in DGVMs are still not clear. In this study, we employ Socio-Economic and natural Vegetation ExpeRimental (SEVER) DGVM to simulate Net Ecosystem Exchange (NEE) flux with large scale National Centers for Environmental Prediction (NCEP) daily climate data as inputs for the years 1997-2000 at 14 Euroflux sites. It is shown that daily local NEE flux on chosen sites can be reasonably simulated, and daily temperature and shortwave radiation are the most essential inputs for daily NEE simulation compared with precipitation and the ratio of sunshine hours. Different running means (1 to 30 days) methods are analysed for each Euroflux site, and the best results of both averaged regression coefficient and averaged slope of regression are discovered by using 5 days running mean method. SEVER DGVM, driven by linearly interpolated daily climate data is compared at the monthly time step with Lund-Potsdam-Jena (LPJ) DGVM, which combines the linear interpolation of daily temperature with stochastic generation of daily precipitation. The comparison demonstrates that the stochastic generation of daily precipitation provides an acceptable fit to local observed NEE, but with a slight decrease in accuracy. Simulation experiments with SEVER DGVM demonstrate that daily local NEE flux inside a grid cell for a region as large as Europe can be modelled by DGVMs, using only large scale climate data as inputs.

Outcomes of hypertrophic obstructive cardiomyopathy patients undergoing alcohol septal ablation with a standard 3 mL dose of ethanol: Focus on long-term safety.

OBJECTIVES: The objective of this research was to assess the long-term results of alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy (HOCM), with all of them receiving a standard 3 mL ethanol dose. BACKGROUND: Generally, ethanol (0.5-3 mL) is infused depending on a septal artery width or interventricular septum (IVS) thickness during alcohol septal ablation. We injected 3 mL of ethanol irrespective of IVS thickness or perforator width in all cases. METHODS: Between 2000 and 2017, 150 HOCM patients (78 males, 72 females) underwent alcohol septal ablation procedures. In all cases we intentionally used the constant dose of ethanol (3 mL). The median of age was 52 (interquartile range: 41-60) years. RESULTS: The median of follow-up was 71 (interquartile range: 36-110) months. Hospital mortality was 0.67% (one patient died of sepsis). Perioperative high-grade atrioventricular blocks required permanent pacemaker implantations-18 (12%). Long-term survival rates were as follows: 95.1% (95% confidence interval [CI]: 92.7-97.5%), 85.8% (95% CI: 83.7-87.0%), and 81.7% (95% CI: 79.7-83.7%) at 5-, 10-, and 15-year follow-up, respectively. One-sample log-rank test revealed no significant differences in 15-year survival rates between the alcohol septal ablation cohort and age- and sex-matched Russian population. CONCLUSIONS: Alcohol septal ablation with the standard (3 mL) ethanol dose is safe and efficient. Survival rates after alcohol septal ablation are comparable with those in age- and sex-matched general Russian population.

Results of Ten-Year Follow-Up of Alcohol Septal Ablation in Patients with Obstructive Hypertrophic Cardiomyopathy.

This study looks at 10-year follow-up outcomes of alcohol septal ablation in patients with obstructive hypertrophic cardiomyopathy. Between 2000 and 2008, 40 patients with obstructive hypertrophic cardiomyopathy (27 males, 13 females) underwent alcohol septal ablation. The median follow-up period was 123 (2-179) months. The mean age ran to 43.8 + 13.9 years. The initial dose of ethanol (3 mL) was chosen for ablation in all cases. The hospital mortality was 0%. Permanent pacemakers were implanted in 3 of 40 (7.5%) cases in the hospital period. The median clinical follow-up was 123 (2-179) months. Survival rates at 1, 5, 10, and 15 years after the procedure were as follows: 97.5% (95% confidence interval [CI], 95.1-99.9%), 92.5% (95% CI, 94.8-90.2%), 85.0% (95% CI, 82.9-87.1%), and 81.3% (95% CI, 79.3-83.3%), respectively. Seven patients died during follow-up. Sudden death was observed in two cases. Permanent pacemakers were implanted in 2 of 40 (5%) cases in the follow-up. The log-rank test revealed no statistically significant difference between the 15-year survival rate in our cohort and age- and sex-matched general Russian population ( p = 0.11113). Alcohol septal ablation provides long-term survival rates that look comparable with age- and sex-matched general population in the 15-year follow-up period.