Spatio-temporal Variation of PM_(2.5) in China from 1998 to 2016

With the rapid development of China's economy,people's demand for a healthy living environment is increasing,and air quality has gradually been widely concerned by all sectors of society.Using the big data of air quality monitoring from 1998 to 2016,based on the exploratory spatio-temporal analysis method,this paper explored the spatio-temporal evolution of PM_(2.5) at the national scale,and drew the following conclusions:①PM_(2.5) heavy pollution is mainly in central and eastern China,north and south China,and the pollution degree is relatively light in northwest and northeast China.Meanwhile,PM_(2.5) concentration in heavily polluted areas increased significantly over time,while PM_(2.5) concentration in low-polluted areas showed a long-term stable trend.②The number and area of cities with moderate and high PM_(2.5) pollution levels showed an inverted U-shaped curve from 1998 to 2016,and 2007 was the inflection point.③The spatial autocorrelation coefficient of PM_(2.5) is high over the years,and the spatial neighbor effect of PM_(2.5) is significant.The high-pollution clusters are mainly concentrated in the Beijing-Tianjin-Hebei region,the Yangtze River Delta and the Pearl River Delta,and the pollution concentration in these three regions has increased rapidly in recent years.It is necessary to focus on joint prevention and control.

Efficacy and safety of subsequent radiotherapy in patients with advanced-stage hepatocellular carcinoma treated with immune checkpoint inhibitors

Background:The development of immunotherapy resistance is associated with a poor prognosis in patients diagnosed with hepatocellular carcinoma(HCC)who are undergoing treatment with immune checkpoint inhibitors(ICI).This study aimed to evaluate the efficacy and safety of subsequent radiotherapy(RT)for patients with advanced-stage HCC who had lesion enlargement or new lesions(NLs)during ICI therapy.Methods:This retrospective observational study enrolled 36 patients with advanced-stage HCC who underwent subsequent RT for lesion enlargement or NLs during ICI therapy from two centers.The primary endpoints were progression-free survival(PFS)and overall survival(OS).The secondary endpoints included objective response rate(ORR),disease control rate(DCR),1-and 2-year local control(LC)rates,in-field PFS(IFPFS),out-field PFS(OFPFS),and safety.Results:The median follow-up time was 15.3 months.The median PFS was 7.4 months[95%confidence interval(CI):3.1-11.7 months],and the median OS was 18.8 months(95%CI:17.1-20.5 months).ORR and DCR were 38.9%and 72.2%,respectively.In addition,the median IFPFS was 17.8 months(95%CI:11.5-24.2 months),median OFPFS was 7.9 months(95%CI:3.4-12.5 months),and estimated 1-and 2-year LC rates were 67.1%and 31.9%,respectively.The most common treatment-related adverse events(all grades)were diarrhea(33.3%),rash(30.6%),and malaise(27.8%);a total of 14(38.9%)patients developed grade 3-4 AEs.Conclusions:Subsequent RT showed reliable antitumor effects and an acceptable safety profile in patients with advanced-stage HCC who had unsatisfactory response to ICI therapy;therefore,it could serve as an optional salvage strategy.

水凝胶表面沟槽内液流诱导制备具有取向碳纳米管的超韧高强纳米复合纤维（英文）

纳米复合纤维由于其广泛的应用前景受到科学家的关注.但是在温和条件下制备具有优异断裂韧性与高强度的纳米复合纤维仍然面临很大的挑战.本文中,我们展示了一种简单的基于液流组装的策略用于制备具有超高断裂韧性与强度的纳米复合纤维.在准液态的水凝胶表面和重力的双重作用下,含有碳纳米管的水溶液可以沿水凝胶沟槽极快速地流动,从而诱导碳纳米管取向排列.我们制备出的纳米复合纤维拉伸强度和断裂韧性分别高达643±27 MPa和77.3±3.4 MJ m-3,极限断裂伸长率14.8±1.5%.这种具有较强普适性和高效率的液流诱导取向策略为高性能纳米复合纤维的实际应用提供了新的可行的发展方向.