Methane Emissions from Wetlands in China and Their Climate Feedbacks in the 21st Century.

Wetlands are large sinks of carbon dioxide (CO2) and sources of methane (CH4). Both fluxes can be altered by wetland management (e.g., restoration), leading to changes in the climate system. Here, we use multiple models to assess CH4 emissions and CO2 sequestration from the wetlands in China and the impacts on climate under three climate scenarios and four wetland management scenarios with various levels of wetland restoration in the 21st century. We find that wetland restoration leads to increased CH4 emissions with a national total of 0.32-11.31 Tg yr-1. These emissions induce an additional radiative forcing of 0.0005-0.0075 W m-2 yr-1 and global annual mean air temperature rise of 0.0003-0.0053 °C yr-1, across all future climate and management scenarios. However, wetland restoration also resulted in net CO2 sequestration, leading to a combined net greenhouse gas sink in all climate management scenarios, except in the highest restoration level combined with the hottest climate scenario. The highest climate cooling was achieved under medium restoration, with the climate scenario consistent with the Paris agreement target of below 2 °C, with a cumulative global warming potential of -3.2 Pg CO2-eq (2020-2100). Wetland restoration in the Qinghai-Tibet Plateau offers the greatest cooling effect.

A Note on Causation versus Correlation in an Extreme Situation.

Recently, it has been shown that the information flow and causality between two time series can be inferred in a rigorous and quantitative sense, and, besides, the resulting causality can be normalized. A corollary that follows is, in the linear limit, causation implies correlation, while correlation does not imply causation. Now suppose there is an event A taking a harmonic form (sine/cosine), and it generates through some process another event B so that B always lags A by a phase of π/2. Here the causality is obviously seen, while by computation the correlation is, however, zero. This apparent contradiction is rooted in the fact that a harmonic system always leaves a single point on the Poincaré section; it does not add information. That is to say, though the absolute information flow from A to B is zero, i.e., TA→B=0, the total information increase of B is also zero, so the normalized TA→B, denoted as τA→B, takes the form of 00. By slightly perturbing the system with some noise, solving a stochastic differential equation, and letting the perturbation go to zero, it can be shown that τA→B approaches 100%, just as one would have expected.

Tumor-suppressive microRNA-449a induces growth arrest and senescence by targeting E2F3 in human lung cancer cells.

MicroRNA-449a (miR-449a) was significantly downregulated in 156 lung cancer tissues (p<0.001). We found that the low expression of miR-449a was highly correlated with cancer recurrence and survival of lung cancer patients. The transient introduction of miR-449a caused cell cycle arrest and cell senescence in A549 and 95D cells. Further studies revealed that E2F3 was a direct target of miR-449a in lung cancer cells. miR-449a also suppressed tumor formation in vivo in nude mice. These results suggest that miR-449a plays an important role in lung cancer tumorigenesis and that miR-449a might predict cancer recurrence and survival of lung cancer patients.

'Zuoyuezi' after caesarean in China: an interview survey.

While studying caesarean decision-making in China, the increasing popularity of 'zuoyuezi' emerged. This paper addresses this development, the reasons and implications. We tape-recorded semi-structured interviews in three industrial cities in China. The three groups of informants comprised women in the first-week after caesarean, women eight months after caesarean and health-workers/others. Mandarin or local dialects were used. The data were transcribed and analysed in Chinese and then selected quotes were translated into English. We found that the re-emergence and social modification of zuoyuezi is closely associated with the rising caesarean rate. This custom has been regarded as a crucial rite-of-passage for the woman's recovery and transition to motherhood after childbirth. Its particular importance after caesarean became apparent in this study. Conclusions are drawn about the place of ritual and tradition in 21st century China.