| 1 | 青藏高原西部昂拉仁错古湖岸钙华沉积的地球化学特征及环境意义显示文摘通过对青藏高原西部昂拉仁错湖古湖岸阶地钙华常量地球化学元素的分析,探讨了钙华沉积的常量元素特征及其古环境意义。结果显示:钙华中CaO含量达34.75%~58.48%,是其主要组分;此外还含有少量的MgO,K_2O和Na_2O等,其含量低于3%,是湖泊自生作用形成的矿物。与湖泊古水位对比显示,元素Mg的含量及Mg/Ca比值等对湖泊水位的响应没有明显规律性;在古湖面高度约4777±5m之上,K_2O和Na_2O的含量低并且稳定,在古湖面4777±5m之下,K_2O和Na_2O的含量随湖泊水位下降逐渐增加。结合现代湖泊钙华的沉积特征,结果显示K_2O和Na_2O的含量随湖泊盐度增加而增加,表明钙华中K_2O和Na_2O含量与湖泊水位可能呈反相关关系,是潜在的重建湖泊水位或盐度的代用指标。同时发现,在湖泊相对淡化阶段,湖水中的元素K和Na处于富集阶段,钙华中K_2O和Na_2O含量低且稳定;而当湖泊进入咸水阶段,湖水中的K^+和Na^+离子接近饱和,钙华中的元素K和Na逐渐富集,因此钙华中K_2O和Na_2O含量增加是湖泊进入咸水阶段的重要特征。基于这些事实,推断当该湖泊水位降至4777±5m左右时,湖水的性质开始向钠-氯型转化,是昂拉仁错湖泊演化过程中的一个重要转折点。 | 雷国良 张虎才 李志忠 Adam M.Hudson 朱芸 姜修洋 陈秀玲 常凤琴 李华勇 | 2013 | 第四纪研究2013，33，5： | 7 |
| 5 | Social-epigeneticmediators for racial disparities in pulmonary impairment among childhood cancer survivors显示文摘Dear Editor Previous research found that childhood cancer survivors of African ancestry have significantly higher morbidity and mortality than those of European ancestry[1].However,after adjusting for socio-economic factors,the magnitudes of racial health disparities are either substantially decreased or become statistically non-significant[1],suggesting that social and economic determinants may contribute to racial health disparities.Recently,we conducted epigenome-wide association studies(EWAS)for three key social determinants of health(SDOHs),namely,personal educational attainment,personal income,and neighborhood deprivation among survivors of childhood cancer,where 130 epigenome-wide significant SDOH-CpG associationswere identified among European ancestry survivors,and 25 of which were also validated in African ancestry survivors[2].Notably,many SDOH-associated CpG sites are also associated with tobacco use. | Nan Song Qian Dong Cheng Chen Qian Li Heather Mulder Emily Plyler John Easton Emily Walker Scott Olson Geoffrey Neale Kevin RKrull Deo Kumar Srivastava Kirsten K.Ness Jinghui Zhang Melissa M.Hudson Leslie L.Robison I-Chan Huang Zhaoming Wang | 2023 | Cancer Communications2023，43，2： | 0 |
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