Understanding the interplay of climatic and biological events in deep time requires resolving the precise timing and pattern of paleotemperature changes and their temporal relationship with carbon cycle variations and biodiversity fluctuations. In situ oxygen isotope analyses of conodont apatite from South China enables us to reconstruct high-resolution seawater temperature records across the Permian-Triassic boundary (PTB) intervals in the upper slope (Meishan), lower slope (Shangsi), and carbonate platform (Daijiagou and Liangfengya) settings. Constrained by the latest high-precision geochronological dates and high-resolution conodont biozones, we can establish the temporal and spatial patterns of seawater temperature changes and assess their potential connections with the carbon cycle disruption and biodiversity decline. We find a rapid warming of~10°C during the latest Permian-earliest Triassic that postdated the onset of the negative shift in δ 13 C carb by~81 kyr (thousand years), the abrupt decline in δ 13 C carb by~32 kyr and the onset of mass extinction by~23 kyr, which contradicts previous claims that the extreme temperature rise started immediately before or coincided with the onset of mass extinction. Our new evidence indicates that climate warming was most likely not a direct cause for the main pulse of the end-Permian mass extinction (EPME), but rather a later participant or a catalyst that increased the pace of the biodiversity decline. In addition, a prominent cooling is recorded in the earliest Changhsingian, with the main phase (a drop of~8°C in~0.2 Ma) confined to the lower part of the Clarkina wangi zone and synchronous with the positive limb of the carbon isotope excursion (CIE) around the Wuchiapingian-Changhsingian boundary (WCB) in Meishan and Shangsi. Further long-term and high-resolution studies from other sections are needed to confirm the full contexts and underlying dynamics of the WCB "cooling event".
Suspended particulate matter samples were collected monthly for more than 2 years in Nanjing, China to examine seasonal changes in the Sr-Nd isotopic compositions of the lower Changjiang River (CR
Malignant fibrous histiocytoma (MFH) is an aggressive soft tissue sarcoma known to occur in various organs. Primary MFH arising in the lung is quite rare. Herein we report a case of a 61-year-old male with primary pulmonary MFH and explore the underlying molecular mechanisms by next-generation sequencing (NGS). Five gene mutations in TSC2, ARID1B, CDK8, KDM5C and CASP8 were detected, and the mTOR inhibitor might be an effective treatment for this patient. In addition, we reviewed the scientific literature of approximately 23 primary pulmonary MFH case reports since 1990 and summarized the clinical features and prognosis of this rare pulmonary malignant tumor.
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