Researchers are exploring whether these ubiquitous fluorinated molecules might worsen infections or hamper vaccine effectiveness.
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Contributed by Peter M. Shearer, November 12, 2011 (sent for review September 27, 2011)
Article Figures & SI
Figures
- Fig. 1.
(A) Global earthquake magnitudes since 1900 after regional declustering of events. (B)–(D) Yearly rates of M≥8, M≥7.5, and M≥7 earthquakes. Rates are five-year running averages.
Tables
- Table 1.
Estimated p values for the hypothesis that times of events in the original and regionally declustered catalogs are independent, identically distributed uniform random variables, for several hypothesis tests
Magnitude threshold Removed Events Estimated p value KS PD MC 7.0 none 1756 0.0% 0.0% 8.6% AS 759 7.5% 76.6% 71.4% AS, FS 502 16.7% 83.4% 60.8% 7.5 none 444 22.9% 24.1% 62.0% AS 330 94.0% 88.8% 10.0% AS, FS 268 82.3% 95.1% 56.3% 8.0 none 82 33.8% 79.1% 25.7% AS 75 60.3% 89.4% 22.3% AS, FS 72 49.0% 89.8% 34.4% Column 1: Magnitude threshold. Column 2: Events removed by declustering: “AS” means aftershocks were removed, “AS, FS” means both aftershocks and foreshocks were removed, and “none” means there was no declustering. Column 3: Events in the catalog with magnitude greater than or equal to the threshold, after any declustering. Column 4: p value for the Kolmogorov-Smirnov test. Column 5: p value for the Poisson dispersion test using 100 windows. Column 6: p value for the multinomial chi-square test using 100 windows. Each estimated p value is the percentile of the observed value of the corresponding test statistic among 100,000 values of that statistic obtained in simulations in which event times are independent, identically distributed uniform random variables. The standard error of the estimated p values is on the order of 0.16%.
Global risk of big earthquakes has not recently increased
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- Physical Sciences
- Earth, Atmospheric, and Planetary Sciences
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