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We report a long-time working femtosecond laser using metal-free sapphire-based graphene as a saturable absorber (SA). The sapphire-based graphene yielded excellent nonlinear saturable absorption properties and was demonstrated to be suitable as an SA for an ultrafast solid-state laser. Stable mode-locked pulses of 325 fs were obtained at a central wavelength of 1032 nm with a repetition rate of 66.3 MHz. At pump power of 8.23 W the average output power was 1.78 W and the highest pulse energy reached 26.8 nJ with a peak power of 72.6 kW. Our work opens up a facile route for making reliable graphene SA in the mode-locking technique and also displays an exciting prospect in making low-cost and ultrafast lasers.

Episodic explosive volcanic eruptions are a natural part of the climate system but are often omitted from atmosphere‐ocean general circulation model (AOGCM) preindustrial spin‐up and control experiments. This omission imposes a negative bias on ocean heat uptake in simulations of the historical period. In models of a range of complexity, we find that global‐mean sea level rise due to thermal expansion during the last ∼ 150 years is consequently underestimated by 5–30 mm, which is a substantial proportion of the model mean of 50 mm in Coupled Model Intercomparison Project Phase 3 AOGCMs with anthropogenic forcing only, and is therefore important in accounting for 20th century sea level rise. We test and recommend a procedure for removing the bias. Volcanic forcing is often omitted from AOGCM control experimentsThis causes a substantial underestimate of historical ocean thermal expansionA method to correct the underestimate is described and verified

To assess rubella and measles susceptibility among women of childbearing age we conducted a cross-sectional seroprevalence study in four cities and one rural area in Argentina. A convenience sample of women aged 15–49 years seeking care in public health-care institutions was selected (n=2804). Serum specimens were tested for rubella and measles IgG antibody titres. The overall susceptibility to rubella and measles was 8·8 and 12·5% respectively. Seroprevalence differences were found for both rubella (P<0·001) and measles (P=0·002) across sites. Rubella seroprevalence was higher in women aged 40 years than in younger women (P=0·04). Measles seroprevalence tended to increase with age (P<0·001). Approximately 15% of women aged 15–29 years were not immune to measles. No risk factors were associated with rubella seronegativity; however, age (P<0·001) and having less than four pregnancies (P<0·001) were factors associated with measles seronegativity. Our findings support the introduction of supplemental immunization activities targeting adolescents and young adults to prevent congenital rubella syndrome and measles outbreaks over time.

The most recent Intergovernmental Panel on Climate Change assessment report concludes that the Atlantic Meridional Overturning Circulation (AMOC) could weaken substantially but is very unlikely to collapse in the 21st century. However, the assessment largely neglected Greenland Ice Sheet (GrIS) mass loss, lacked a comprehensive uncertainty analysis, and was limited to the 21st century. Here in a community effort, improved estimates of GrIS mass loss are included in multicentennial projections using eight state‐of‐the‐science climate models, and an AMOC emulator is used to provide a probabilistic uncertainty assessment. We find that GrIS melting affects AMOC projections, even though it is of secondary importance. By years 2090–2100, the AMOC weakens by 18% [−3%, −34%; 90% probability] in an intermediate greenhouse‐gas mitigation scenario and by 37% [−15%, −65%] under continued high emissions. Afterward, it stabilizes in the former but continues to decline in the latter to −74% [+4%, −100%] by 2290–2300, with a 44% likelihood of an AMOC collapse. This result suggests that an AMOC collapse can be avoided by CO2mitigation. This is the first model intercomparison concerning climate change including Greenland melt and a probabilistic uncertainty assessmentImpact of Greenland melt on future overturning circulation is small but nonnegligible especially for high‐end global warming scenariosLikelihood of a full overturning collapse remains exceptionally small if global warming is limited to less than 5 K