A re-evaluation of the average chain length of lacustrine sedimentary n-alkanes as a paleoproxy on the Qinghai-Tibet Plateau

Long-chain n-alkanes are one of the most common organic compounds in terrestrial plants and they are well-preserved in various geological archives.n-alkanes are relatively resistant to degradation and thus they can provide high-fidelity records of past vegetation and climate changes.Nevertheless,previous studies have shown that the interpretation of n-alkane proxies,such as the average chain length(ACL),is often ambiguous since this proxy depends on more than one variable.Both vegetation and climate could exert controls on the n-alkane ACL,and hence its interpretation requires careful consideration,especially in regions like the Qinghai-Tibet Plateau(QTP)where topography,biome type and moisture source are highly variable.To further evaluate the influences of vegetation and climate on the ACL in high-elevation lakes,we examined the n-alkane distributions of the surface sediments of 55 lakes across the QTP.Our results show that the ACL across a climatic gradient is significantly affected by precipitation,rather than by temperature.The positive correlation between ACL and precipitation may be because of the effect of microbial degradation during deposition.Finally,we suggest that more caution is needed in the interpretation of ACL data in different regions.

Metabolomics in Schizophrenia and Major Depressive Disorder

定义 pathophenotype，和环境、随机的影响，疾病遗传型的系统水平后果是在精神病学的一项艰巨任务。它也是一个呼吁的目标，对对大脑混乱的欣赏的给定的成长需要生物复杂性，对识别新奇的药目标的诊断测试开发和雄心的渴望。这里，我们集中于精神分裂症和主要压抑的混乱并且在 metabolomics 研究加亮最近的进展。作为一个系统生物学工具， metabolomics 保持一条诺言参加在基因和环境之间的阐明的相互作用，复杂行为的特点和精神病理学风险地翻译研究。