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Peer reviewed: True, Funder: Big Questions Institute, Annually resolved measurements of the radiocarbon content in tree-rings have revealed rare sharp rises in carbon-14 production. These ‘Miyake events’ are likely produced by rare increases in cosmic radiation from the Sun or other energetic astrophysical sources. The radiocarbon produced is not only circulated through the Earth’s atmosphere and oceans, but also absorbed by the biosphere and locked in the annual growth rings of trees. To interpret high-resolution tree-ring radiocarbon measurements therefore necessitates modelling the entire global carbon cycle. Here, we introduce ‘ ticktack ’ ( https://github.com/SharmaLlama/ticktack/ ), the first open-source Python package that connects box models of the carbon cycle with modern Bayesian inference tools. We use this to analyse all public annual 14 C tree data, and infer posterior parameters for all six known Miyake events. They do not show a consistent relationship to the solar cycle, and several display extended durations that challenge either astrophysical or geophysical models.

Introduction An outbreak of Influenza B occurred at a large United Kingdom (UK) regional adult cystic fibrosis (CF) centre in May 2016. This was late in the UK 2015–2016 influenza season and occurred on a specialist ward with strict infection control procedures. This study investigates the spread of influenza, clinical consequences and potential contributing factors. Methods Patient records, clinical status and pulmonary function data were reviewed for all inpatients during this period. Respiratory viral PCR results, influenza vaccination status of patients and staff, and environmental factors were also recorded. Affected patients were prospectively monitored for the following three months. Results 10 of 21 inpatients developed influenza B between 5th and 12th May 2016, an attack rate of 48%. All those characterised were confirmed as the same strain of influenza B/Victoria-lineage. Influenza infection resulted in a mean FEV1 reduction of 10.5% (SD 11.3, p = 0.012), which persisted at 3 months post infection (p = 0.003). Nine of the affected cases rooms were in close proximity on the ward while patients in the two isolation rooms with enhanced ventilation did not become infected. Ventilation measurements in affected rooms ranged from 1.75 to 2.10 air changes/hour, below national recommendations. Seventy percent of affected inpatients had received the 2015/16 trivalent seasonal influenza vaccine, which did not contain a B/Victoria-lineage influenza B virus. Conclusion This influenza B outbreak in CF adults had a high attack rate and a significant clinical impact. Room ventilation and a limited protection from the seasonal influenza vaccine were possible contributory factors.