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The Ediacaran–Cambrian Phosphogenic Episode is the Earth's first true phosphogenic event and resulted in worldwide phosphate deposits, which occurred during the processes of the Neoproterozoic Oxygenation Event. The Ediacaran Doushantuo Formation (ca. 635–551 Ma) of Weng'an area in central Guizhou, South China, contains two economic phosphorite beds (the Lower and Upper Phosphorite Beds). This paper presents a detailed stratigraphic, sedimentological and mineralogical study of multiple outcrop and drill core sections of the Doushantuo Formation across the Weng'an area, and identified 11 lithofacies and 4 types of phosphatic grains. Significant differences in lithofacies and grain types between the upper and lower phosphate deposits are observed, indicating that the two sets of phosphate deposits are the products of two distinct phosphogenic processes. The Lower Phosphorite Bed mainly consists of banded and laminated phosphorites, contains micro-oncoids formed by microbially-mediated precipitation and peloids formed by in-situ chemically oscillating reactions, indicating a biochemical and chemical enrichment of phosphorus to sediments during the Early Ediacaran Period. The Upper Phosphorite Bed is mainly composed of carbonaceous, massive, and stromatolitic phosphorites, contains bioclasts (phosphatized spheroidal fossils), and intraclasts formed by hydrodynamic agitation, suggesting that the major accesses of phosphorus to sediments were the remineralization of organic P. Deposition of the two economic phosphorite beds was controlled by two sea-level cycles. Such differences have also been documented in contemporaneous phosphate-bearing successions in Brazil and Mangolia, indicating a significant shift in global phosphogenic mechanism during the early and middle Ediacaran, which may be due to the changes in redox conditions in seawater, associated with the Neoproterozoic Oxygenation Event. These regional active P-cycle processes could produce more free oxygen, which may have contributed to the upcoming Phanerozoic global oxidation. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the left ventricular (LV) myocardial tissue characteristics in early adult obesity and its association with regional adipose tissue and ectopic fat deposition. Methods: Forty-nine obese adults (mean body mass index: 29.9 ± 2.0 kg/m2) and 44 healthy controls were prospectively studied. LV native and post-contrast T1 values, extracellular volume fraction (ECV), regional adipose tissue (epicardial, visceral, and subcutaneous adipose tissue (EAT, VAT, and SAT)), and ectopic fat deposition (hepatic and pancreatic proton density fat fractions (H-PDFF and P-PDFF)) based on magnetic resonance imaging were compared. The association was assessed by multivariable linear regression. Results: The obese participants showed reduced global ECV compared to the healthy controls (p < 0.05), but there was no significant difference in global native or post-contrast T1 values between the two groups. Additionally, the obese individuals exhibited higher EAT, VAT, SAT, H-PDFF, and P-PDFF than the controls (p < 0.05). ECV was associated with insulin resistance, dyslipidemia, and systolic blood pressure (SBP) (p < 0.05). Multiple linear regression demonstrated that H-PDFF and SAT were independently associated with ECV in entire population (β = − 0.123 and − 0.012; p < 0.05). Conclusions: Reduced myocardial ECV in patients with mild-to-moderate obesity and its relationship to SBP may indicate that cardiomyocyte hypertrophy, rather than extracellular matrix expansion, is primarily responsible for myocardial tissue remodeling in early adult obesity. Our findings further imply that H-PDFF and SAT are linked with LV myocardial tissue remodeling in this cohort beyond the growth difference and cardiovascular risk factors. Clinical trials registration: Effect of lifestyle intervention on metabolism of obese patients based on smart phone software (ChiCTR1900026476). Clinical relevance statement: Myocardial fibrosis in severe obesity predicts poor prognosis. We showed that cardiomyocyte hypertrophy, not myocardial fibrosis, is the main myocardial tissue characteristic of early obesity. This finding raises the possibility that medical interventions, like weight loss, may prevent cardiac fibrosis. Key Points: • Myocardial tissue characteristics in early adult obesity are unclear. • Myocardial extracellular volume fraction (ECV) can be quantitatively evaluated using T1 mapping based on cardiac magnetic resonance imaging (MRI). • Cardiac MRI-derived ECV may noninvasively evaluate myocardial tissue remodeling in early adult obesity. [ABSTRACT FROM AUTHOR]

Focuses on a study of the geochemical characteristics of the independent cadmium deposit at Niujiaotang, Duyun, Guizhou, China. Geological characteristics of the deposit; Distribution and mode of occurrence of cadmium; Geochemical characteristics of the fluid inclusions in the deposit; Summary.

Hepatectomy of large hepatocellular carcinomas (>10 cm) in over 70 year-old patients is presumed futile. We retrospectively reviewed 5970 patients with liver tumors Jan 2010 through Dec 2016 in our institute, of them, 37 older patients with large hepatocellular carcinomas staged I-III and Child-Pugh A liver functions receiving conservative treatments (conservative group, n = 37) and 16 older patients with large hepatocellular carcinomas staged I- III who underwent partial hepatectomy (resection group, n = 16) were included, the risk factors for poor survival were analyzed by univariate and multivariate analyses. Compared with the conservative treatments, Partial hepatectomy achieved better median survival time (25.5 months versus 11 months, log-rank = 0.0001) and better median performance status (1 versus 3, p = 0.023), there was different in Charlson comorbidity index (p = 0.019). For the conservative group, the 3-month, 1, 2, 3-year survival rate was 78.4%, 43.2%, 5.4%, 0%; for the resection group, The 3-month, 1, 2, 3-year survival rate was 100%, 93.7.2%, 56.3%, 12.5%; Multivariate Cox regression analysis showed the Charlson comorbidity index and the performance status associated with poor outcomes of those patients (p = 0.001, 0.018, respectively). Resections of large hepatocellular carcinomas in older patients can be performed safely to prolong life expectancy and improve life quality with or without cancer recurrence. [ABSTRACT FROM AUTHOR]