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• Both mineralogical and geochemical analysis suggest a shift towards more extensive reverse weathering within the uppermost portion of the glaciogenic Nantuo Formation. • This reverse weathering was likely driven by a combination of rising temperatures and pH and high dissolved silica concentrations. • The carbon cycle modeling implies that widespread reverse weathering could have driven a protracted (millions of years) carbon dioxide drawdown following deglaciation. Snowball Earth glaciations are the most extreme climate perturbations recorded in Earth's history. It has been argued that the termination of these events was characterized by a single rapid transition from near-global ice coverage to an ice-free greenhouse climate state. Notably, this deviates with more extended transition periods of ice sheet waxing and waning typical of Phanerozoic glaciations. Using a coupled mineralogical and Mg and Li isotopic approach, we explore the role that authigenic clay formation within the seafloor may have played on Earth's climate during deglaciation of the Marinoan Snowball Earth event. Marine authigenic clay formation—a process referred to as reverse weathering—recycles carbon within the ocean–atmosphere system and acts to elevate atmospheric CO 2 levels. The results indicate a shift towards more extensive reverse weathering within the uppermost portion of the glaciogenic Nantuo Formation in South China. Carbon cycle modeling indicates that widespread reverse weathering could have driven a protracted (millions of years) carbon dioxide drawdown following high carbon dioxide levels expected during deglaciation. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical feature of a family with hereditary hemorrhagic telangiectasia (HHT), and to study the mutation of its related genes., Methods: Medical histories of the family were analyzed to detect HHT patients according to the diagnostic criteria. ENG and ALK-1 genes of the proband and her two daughters were analyzed. DNA from the three patients' peripheral blood was extracted. The exons 2-10 and their intron-exon boundaries of ALK1 were amplified with PCR, and then the PCR products were sequenced and analyzed to identify the mutation., Results: There were 11 people in 41 family members of 4 generations were diagnosed as HHT. The proband and her two daughters suffered from multiple organ damage, the younger daughter appeared only imaging features instead of corresponding clinical symptoms. A missense mutation at the 1321 bp of cDNA (c.1321G>A) was detected in the exon 9 of ALK1, which resulted in valine 441 to methionine replacement in ALK-1 protein (p.Val441Met)., Conclusion: A Chinese family with HHT was studied and a missense mutation (c.1321G>A, p.Val441Met) of ALK-1 was discovered. This mutation is the genetic basis of the family with HHT and is reported for the first time in China. This research will not only help to further investigate molecular mechanism of pathogenesis of HTT, but also provide evidences and references for the following gene screening and genetic counseling on HTT family members.