Human activity causes vibrations that propagate into the ground as high-frequency seismic waves. Measures to mitigate the COVID-19 pandemic caused widespread changes in human activity, leading to a months-long reduction in seismic noise of up to 50%. The 2020 seismic noise quiet period is the longest and most prominent global anthropogenic seismic noise reduction on record. While the reduction is strongest at surface seismometers in populated areas, this seismic quiescence extends for many kilometers radially and hundreds of meters in depth. This provides an opportunity to detect subtle signals from subsurface seismic sources that would have been concealed in noisier times and to benchmark sources of anthropogenic noise. A strong correlation between seismic noise and independent measurements of human mobility suggests that seismology provides an absolute, real-time estimate of population dynamics.

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Somatostatin is useful in preventing post-ERCP pancreatitis. Further studies must be designed to investigate the cost-effectiveness of the drug and to determine the ideal administration route and dosage.

These results support the concept that impaired B-cell function, as reflected by a reduction in the insulin secretion index, is present in beta-thalassaemic patients with normoglycaemia before changes in oral glucose tolerance tests are apparent.

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