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BACKGROUND In recent years, the in situ Hf isotopic determination method of zircon has been widely used in isotopic geochemistry, and has become an important method to explore the genesis of rocks, the source of ore-forming materials and the evolution of crust and mantle. However, for some rocks, the lack of zircon seriously hinders the restriction of formation and evolution. The development of Hf isotopic determination methods for oxide-type U-bearing accessory minerals, such as rutile, cassiterite and columbite is urgently needed. OBJECTIVES In order to accelerate the studies of in situ Hf isotopic determination of oxide-type U-bearing minerals and their application to the geological research. METHODS In situ Hf isotopic analysis of oxide-type U-bearing accessory minerals was reviewed with NEPTUNE multiple-collector inductively coupled plasma-mass spectrometry (MC-ICPMS) and a 193nm excimer laser ablation system. RESULTS Combined with relevant research work in recent years, the development history of Lu-Hf isotope analysis technology for accessory minerals was briefly described, and the latest progress and existing problems in in-situ Hf isotope determination methods for oxide-type uranium-bearing minerals such as rutile, cassiterite and niobite were systematically reviewed. The current technical difficulties such as the correction strategy for isobaric interference, the lack of quality control standard samples, the lower Hf content, and the improvement of analytical sensitivity were discussed in detail. CONCLUSIONS The low Hf content of oxide-type U-bearing accessory minerals requires a larger spot diameter. The femtosecond laser has the characteristics of fine and uniform grain size of the ablation samples. The combination of femtosecond laser and MC-ICPMS (fs-LA-MC-ICPMS) can reduce the spot diameter and improve the spatial resolution, which is the development direction of in situ Hf isotope analysis of oxide-type U-bearing accessory minerals in the future.

BACKGROUND Microbeam analytical technology can be used to accurately analyze the petrography, morphology, structure, component and isotopic composition of ore minerals on the micro-nano scale, which plays a vital role in supporting the detailed research of geoscience. OBJECTIVES To provide a practical technology for visually and quickly identifying the cobalt-bearing minerals and to understand the occurrence of cobalt in the Chambishi copper-cobalt deposit. METHODS Microscopy was combined with microbeam analytical technologies of micro-XRF, EPMA, LA-ICP-MS to develop a method for quickly identifying the cobalt-bearing minerals from copper-cobalt deposits. First, representative thin sections were selected by polarized light microscopy, micro-XRF map scanning was then used to obtain the distribution characteristics of cobalt and combined elements in the thin sections. The polarized light microscopy was used again to identify independent cobalt minerals and cobalt-bearing minerals based on the characteristics of element distribution. Finally, the representative minerals were circled and the main and trace elements were determined by EPMA and LA-ICP-MS. RESULTS The results showed that in the Chambishi Southeast orebody the cobalt not only existed in the form of independent minerals (pentlandite, linnaeite, carrollite), but also occurred in pyrite and pyrrhotite in the form of isomorphism, while the cobalt in the Chambishi West orebody mainly existed in the form of independent mineral—carrollite with a small amount. CONCLUSIONS The combined microbeam analysis method is proposed to quickly and easily identify cobalt-bearing minerals and to study the occurrence of cobalt in the Chambishi Southeast orebody and Chambishi West orebody. It can effectively save the time of identifying minerals by traditional polarized light microscopy and avoid missing identification of some independent cobalt minerals or cobalt-bearing minerals with small particle size or without obvious optical characteristics.

Introduction: Observational studies have discovered a contradictory phenomenon between Helicobacter pylori (H. pylori) infection and inflammatory bowel disease (IBD). The study aimed to confirm the causal association between H. pylori and IBD, including ulcerative colitis (UC) and Crohn's disease (CD). Methods: We conducted a Mendelian randomization (MR) study with two sample Genome-Wide Association Studies (GWAS) to determine whether there is a causal relationship between H. pylori infection and IBD, as well as the possible pathogenic factors that may be involved. The reliability of the main MR assumptions was examined through a series of sensitivity analyses. Results: Two genetic variants (SNPs) previously identified were employed as instrumental variables (IVs) for H. pylori infection. GWAS data for IBD, UC, and CD were obtained from the recent DF10 release10 of the FinnGen study. Our findings indicated a significant association between H. pylori seropositivity and an increased risk of IBD and UC (IBD: OR: 1.16, 95% CI, 1.03–1.31, P < 0.05; UC: OR: 1.22, 95% CI, 1.08–1.37, P < 0.001) while no causal relationship with CD (P > 0.05). Analysis of the main virulence pathogenic factors revealed a causal relationship between cytotoxin-associated protein A (CagA) and IBD and UC (IBD: OR: 1. 06, 95% CI, 1.001–1.11, P < 0.05; UC: OR: 1.07, 95% CI, 1.004–1.14, P < 0.05), while no correlation was found for vacuolar cytotoxin A (VacA) (P > 0.05). After applying the False Discovery Rate (FDR) correction, the causal relationship between CagA and the risk of IBD or UC was no longer statistically significant. Conclusion: This study suggests a potential causal relationship between H. pylori infection and IBD, particularly UC. The effect may be more pronounced in individuals with previous H. pylori infections. [ABSTRACT FROM AUTHOR]

Globally, over the past few decades, extreme river channel deformation has been observed downstream of dams. Specially, estuarine channel deformation and its response to natural and anthropogenic factors are key issues influencing channel regulation and prediction of long‐term stability in large estuarine deltas. Herein, bathymetry data for the upper reaches of the Yangtze Estuary (YE), China was collected for the years 1995, 2003, 2008, 2013, and 2019 to analyze the channel deformation process. Our findings show that the total erosion volume was approximately 11.22 × 108 m3, an equivalent of 15.7 × 108 t of sediment assuming a bulk density of 1.4 t/m3 for the riverbed material during 1995–2019. Meanwhile, the annual erosion rate is 0.63 Mt/year in 1995–2019, and the annual erosion rate is 0.90, 0.12, 0.40 Mt/year in 1995–2003, 2008–2013 and 2013–2019, respectively. Meanwhile, the annual deposition rate is 0.7 Mt/year during 2003–2008. Further analysis indicated that continuous reduction of the sediment load due to the construction of dams (e.g., the Three Gorges Dam) in the basin was a key factor influencing channel erosion over the past 24 years. The channel deformation process was characterized by severe erosion during 1995–2003, a deposition period during 2003–2008, a dynamic equilibrium period from 2008–2013, and an erosion period after 2013. Due to floods with maximum peak discharge lower than 70,000 m3/s, despite the annual sediment load is reduced, the channel deposition phenomenon occurred in 2003–2008. The channel changed from a depositional system to an erosion system during 2008–2013. After 2013, the channel was dominated by extensive erosion, severe local deposition, or severe local erosion as a response to anthropogenic interventions. These findings are of great significance to river management and regulation, as well as to the navigational safety. [ABSTRACT FROM AUTHOR]

The Ganjiang River, one of eight major tributaries of the Yangtze River, located in the western hinterland of the Cathaysia Block, SE China, has a length of 823 km and a drainage area of 82 809 km2, whose detrital zircons provide a valuable means to trace sediment provenances of the river and explore the crustal growth and evolution of the Cathaysia Block. In the current study, 389 concordia zircon U–Pb age spots and rare earth element (REE) contents, in combination with 201 Lu–Hf isotope analyses, have been determined. Oscillatory zoning, high Th/U ratios and REE distribution patterns indicate that most detrital zircon grains are of magmatic origin. The age can be further divided into seven groups: 130–185 Ma with a peak at 153 Ma (7 %); 217–379 Ma with a peak at 224 Ma (16 %); 390–494 Ma with a peak at 424 Ma (37 %); 500–698 Ma with a peak at 624 Ma (5 %); 716–897 Ma with a peak at 812 Ma (10 %); 902–1191 Ma with a peak at 976 Ma (13 %); and 2232–2614 Ma with a peak at 2471 Ma (5 %). The sources of almost all the zircon age groups can be found from the exposed rocks. In particular, Yanshanian, Hercynian to Indosinian, Pan-African, Grenvillian and Palaeoproterozoic–Archaean zircons can be mainly sourced from the northern Guangdong – southern Jiangxi – western Fujian region, while Caledonian zircons come from southern and central Jiangxi, and Jinningian zircons are from central and northern Jiangxi. Most determined zircon grains exhibit negative ε Hf(t) values and TDM2 ages of 797 to 4016 Ma with a wide peak at 1500–2100 Ma and a keen peak at 1824 Ma, suggesting that most zircons are sourced from the reworked ancient crustal materials or crust–mantle mixing. The zircon Hf model age cumulative probability diagram shows that rapid crustal growth took place at the Palaeo- to Mesoproterozoic and that about 90 % of the crust of the Cathaysia Block was formed before 1.5 Ga. [ABSTRACT FROM AUTHOR]

Background/Aims: The embryonic stem cell-derived cardiomyocytes (ES-CMs) serve as potential sources for cardiac regenerative therapy. However, the immature sarcoplasmic reticulum (SR) function of ES-CMs prevents its application. In this report, we examined the effect of puerarin, an isoflavone compound, on SR function of murine ES-CMs. Methods: Murine ES-CMs were harvested by embryoid body-based differentiation method. Confocal calcium imaging and whole-cell patch clamps were performed to assess the function of SR. The mRNA expression levels of SR-related genes were examined by quantitative PCR. The protein expression of sarcoplasmic reticulum calcium-ATPase 2a (SERCA2a) was evaluated by immunofluorescent and western blot. Results: Long-term application of puerarin promotes basic properties of spontaneous calcium transient with increased amplitude, decay velocity, and decreased duration. Puerarin fails to alter ICa,L but increases the Ca2+ content of SR. Puerarintreated ES-CMs have intact SR Ca2+ cycling with more SR Ca2+ reuptake. Long-term application of puerarin asynchronously upregulates the mRNA and protein expression of SERCA2a, as well as the transcripts of calsequestrin and triadin in developing ES-CMs. Application of puerarin during the stage of post-cardiac differentiation upregulates dose-dependently the transcripts of SERCA2a, phospholamban and tridin which can be reversed by the inhibitors of the PI3K/Akt and MAPK/ERK signaling pathways, but shows no effect on the protein expression of SERCA2a. Conclusion: This study demonstrates that long-term puerarin treatment enhances Ca2+ reuptake and Ca2+ content via upregulation of SERCA2a. [ABSTRACT FROM AUTHOR]