Background: A range of case fatality ratio (CFR) estimates for COVID-19 have been produced that differ substantially in magnitude. Methods:We used individual-case data from mainland China and cases detected outside mainland China to estimate the time between onset of symptoms and outcome (death or discharge from hospital). We next obtained age-stratified estimates of the CFR by relating the aggregate distribution of cases by dates of onset to the observed cumulative deaths in China, assuming a constant attack rate by age and adjusting for the demography of the population, and age-and location-based underascertainment. We additionally estimated the CFR from individual line-list data on 1,334 cases identified outside mainland China. We used data on the PCR prevalence in international residents repatriated from China at the end of January 2020 to obtain age-stratified estimates of the infection fatality ratio (IFR). Using data on age-stratified severity in a subset of 3,665 cases from China, we estimated the proportion of infections that will likely require hospitalisation. Findings:We estimate the mean duration from onset-of-symptoms to death to be 17.8 days (95% credible interval, crI 16.9-19.2 days) and from onset-of-symptoms to hospital discharge to be 22.6 days (95% crI 21.1-24.4 days). We estimate a crude CFR of 3.67% (95% crI 3.56%-3.80%) in cases from mainland China. Adjusting for demography and under-ascertainment of milder cases in Wuhan relative to the rest of China, we obtain a best estimate of the CFR in China of 1.38% (95% crI 1.23%-1.53%) with substantially higher values in older ages. Our estimate of the CFR from international cases stratified by age (under 60 / 60 and above) are consistent with these estimates from China. We obtain an overall IFR estimate for China of 0.66% (0.39%-1.33%), again with an increasing profile with age.Interpretation: These early estimates give an indication of the fatality ratio across the spectrum of COVID-19 disease and demonstrate a strong age-gradient in risk.

11Bird strike can cause serious risks to the safety of air travel. In this paper, the aim is to improve 12 design by determining deformation and damage mechanisms of laminated glass windows when 13 subjected to high velocity soft impacts. To achieve this, laboratory-scale impact experiments 14 using bird substitute materials were performed in the velocity range of 100-180 m s -1 . An 15 important step forward is that high-speed 3D Digital Image Correlation (DIC) has effectively 16 been employed to extract the full-field deformation and strain on the back surface of the 17 specimens during impact. The finite element simulations were performed in Abaqus/explicit 18 using Eulerian approach and were able to represent successfully the experiments. 19

The polytypism of SiC, phase transformation of ZrB 2 and the interfaces between SiC and ZrB 2 were investigated using high resolution TEM in a hot pressed 10 vol.%SiC-ZrB 2 composite. In most cases, no grain boundary interphases between hexagonal ZrB 2 and 6H-SiC phases were observed with SiC being both inter-and intragranular. Occasionally, 6H-SiC transformed into 3C and 15R and hexagonal ZrB 2 transformed into cubic ZrB. High resolution TEM showed no grain boundary interphases in most regions. Energy dispersive X-ray spectroscopy and electron energy-loss spectroscopy analyses showed the presence of oxygen throughout the sample. The phase transformation of SiC and ZrB 2 , and the interphase formation between SiC and ZrB 2 grains are discussed.

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