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It is a great challenge for sedimentologists to perform the facies analysis of shales due to the lack of macro-structures and high heterogeneity in shale, and thus, conventional research methods are poorly applied in the field of shale sedimentology. To establish a typical depositional model for marine shales, a new method adopted from marine carbonate rocks was employed to perform the microfacies analysis of marine shales of the Wufeng and Longmaxi Formation in Sichuan Basin. This method emphasizes the fact that many skeletal constituents in marine shales have specific bathymetric distributions, allowing for a better understanding of the depositional process of shales. With this approach, a total of nine microfacies were identified and two depositional models for marine shales were proposed. The depositional models show that sea levels were high during the Middle to Late Wufeng period, which was followed by a rapid regression that led to a significant sea-level drop by over 50 m at the topmost of the Wufeng Formation, and consequently, widespread fine-grained sandy shales with large amounts of benthic bioclasts were deposited in the study region. The eustatic sea-level changes recovered by using the method of microfacies analysis are in line with the global trend, indicating that the method has promising applications in the field of marine shale sedimentology.

Simple Summary: The current dietary structure of humans consists of a higher proportion of ω-6 and a lower proportion of ω-3 polyunsaturated fatty acids (ω-3 PUFAs). Given the limited availability of fish oil and other marine resources, which are also prone to oxidation, identifying stable sources of ω-3 PUFAs and their products has become a prominent research topic. This experiment investigates the effects of schizochytrium algae powder (SAP) or schizochytrium algae oil (SAO) as ω-3 PUFA raw materials on the production performance, egg quality, serum immunity, serum lipids, and fatty acid composition in the eggs of laying quails. The results indicate that the immune function and lipid metabolism of quails were improved with the addition of 3.2% SAP. This addition also significantly increases the ω-3 PUFA content in the eggs, providing a valuable reference for new sources of ω-3 PUFA in food. The objective of this experiment is to investigate the effects of SAP or SAO as ω-3 PUFA raw materials on production performance, egg quality, serum immunity, serum lipids, and fatty acid deposition patterns in the eggs of laying quails. Chinese yellow-feathered quails served as the experimental subjects. A single-factor design was employed to randomly assign 1288 quails into four treatment groups, with seven replicates per treatment and 46 birds in each replicate. The groups included a control group (basal diet with no SAP), 1.6% SAP, 3.2% SAP, and 0.8% SAP + 0.3% SAO. The results indicate that: (1) Compared to the control group, the 0.8% SAP + 0.3% SAO group exhibited a reduction in daily egg-laying rate and egg mass, alongside an increased FCR; (2) the 3.2% SAP group enhanced egg yolk color, while the 1.6% SAP group reduced eggshell thickness, and the 0.8% SAP + 0.3% SAO group increased eggshell thickness; (3) compared to the control group, the 3.2% SAP group decreased total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) levels in serum; the addition of either the 3.2% SAP or the 0.8% SAP + 0.3% SAO group significantly elevated quail serum immunoglobulin M (IgM) levels (p < 0.05); (4) in comparison to the control group, the addition of SAP or with SAP increased the contents of monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), docosahexaenoic acid (DHA), and ω-3 PUFA in 56-day-old egg yolks while reducing the ω-6/ω-3 ratio (p < 0.05). These findings suggest that SAP as a source of ω-3 PUFA raw materials could improve quail health by improving lipid metabolism and immunity. 3.2% SAP was recommended as the optimal level to produce the enriched ω-3 PUFA quail eggs with the ω-3 PUFA ≥ 300 mg/100 g. [ABSTRACT FROM AUTHOR]

Marine–continental transitional shale has become a new field for shale gas exploration and development in recent years. Its reservoir characteristics analysis lags significantly behind that of marine shale, which restricts the theoretical research on the accumulation of marine–continental transitional shale and the progress of exploration and development. The shale pore system is complex and has strong heterogeneity, which restricts the fine evaluation and optimization of the reservoir. Based on nitrogen adsorption–desorption experiments, the morphology and structural characteristics of coal-bearing shale pores were analyzed, and then the micro-pore structure heterogeneity was quantitatively characterized based on fractal theory and nitrogen adsorption–desorption data, and the relationship between pore structure parameters and their influence on fractal characteristics were discussed. The hysteresis loop of nitrogen desorption isotherm mainly belongs to type B, indicating ink bottle, flat plate, and slit are the main pore shapes. The pore size distribution curves are left unimodal or multimodal, with the main peak around 4 nm and 20–60 nm. Smaller pores develop a larger specific surface area, resulting in a high value of fractal dimension (2.564 to 2.677). The rougher the pore surface and the larger the specific surface area provide an adequate adsorption site for shale gas adsorption and aggregation. Thus, fractal characteristics conduced to understand the pore structure, heterogeneity, and gas-bearing property of coal-bearing shale. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) can be completely suppressed after antiviral treatment; however, some patients with chronic hepatitis B (CHB) exhibit elevated alanine aminotransferase (ALT) levels and sustained disease progression. This study provides novel insights into the mechanism and potential predictive biomarkers of persistently elevated ALT (PeALT) in patients with CHB after complete viral inhibition. Patients having CHB with undetectable HBV DNA at least 12 months after antiviral treatment were enrolled from a prospective, observational cohort. Patients with PeALT and persistently normal ALT (PnALT) were matched 1:1 using propensity score matching. Correlations between plasma metabolites and the risk of elevated ALT were examined using multivariate logistic regression. A mouse model of carbon tetrachloride‐induced liver injury was established to validate the effect of key differential metabolites on liver injury. Of the 1238 patients with CHB who achieved complete viral suppression, 40 (3.23%) had PeALT levels during follow‐up (median follow‐up: 2.42 years). Additionally, 40 patients with PnALT levels were matched as controls. Ser‐Phe‐Ala, Lys‐Ala‐Leu‐Glu, 3‐methylhippuric acid, 3‐methylxanthine, and 7‐methylxanthine were identified as critical differential metabolites between the two groups and independently associated with PeALT risk. Ser‐Phe‐Ala and Lys‐Ala‐Leu‐Glu levels could be used to discriminate patients with PeALT from those with PnALT. Furthermore, N‐acetyl‐ l‐methionine (NALM) demonstrated the strongest negative correlation with ALT levels. NALM supplementation alleviated liver injury and hepatic necrosis induced by carbon tetrachloride in mice. Changes in circulating metabolites may contribute to PeALT levels in patients with CHB who have achieved complete viral suppression after antiviral treatment. [ABSTRACT FROM AUTHOR]

Lacustrine strata-bound magnesite deposits associated with Alpine-type ultramafic rocks are hydrothermal in origin. The magnesite ores of the Kamado deposit are unconformably underlain by mid-Jurassic marine carbonate and ultramafic rocks of the Bangong-Nujiang ophiolite suite and are in fault contact with hanging wall rocks composed of siliceous sinter. Three types of cryptocrystalline magnesite ores can be identified in Kamado: (1) strata-bound massive magnesites, representing the main ore type in the upper part; (2) banded ores in the lower part; and (3) some vein and stockwork ore in the ultramafic wall rocks. Integrated scanning electron microscopy, C–O isotope analysis, and geochemical analyses were carried out on the Kamado deposit. The results indicate that: (1) the orebody is composed of magnesite, with accessory minerals of aragonite, opal, and chromite; (2) the siliceous sinter and relatively high B (32.0–68.1 ppm) and Li (14.7–23.4 ppm) contents of the magnesite ores reflect long-term spring activity in Kamado; (3) the light carbon (δ13CV-PDB: −4.7 ± 0.3‰ to −4.1 ± 0.6‰) and oxygen isotopic compositions (δ18OV-SMOW: +12.3 ± 0.3 to +16.3 ± 0.1‰) of the stockwork ores in the foot wall rocks indicated that the carbon in fractures in the ultramafic rocks is from a mixture of marine carbonate and oxidized organic-rich sedimentary rocks, reflecting a typical "Kraubath-type" magnesite deposit; and (4) the relatively heavy carbon isotopic (δ13CV-PDB: +8.7 ± 0.4‰ to +8.8 ± 0.3‰) composition of the banded magnesite ores in the lower segment may have formed from heavy CO2 generated by anaerobic fermentation in the lakebed. Additionally, the carbon isotopic (δ13CV-PDB: +7.3 ± 0.3‰ to +7.7 ± 0.7‰) composition of the massive magnesite ores in the upper segment indicates a decline in the participation of anaerobic fermentation. As this economically valuable deposit is of the strata-bound massive ore type, Kamado can be classified as a lacustrine hydrothermal-sedimentary magnesite deposit, formed by continuous spring activities under salt lakes on the Tibetan Plateau, with the Mg mainly being contributed by nearby ultramafic rocks and the carbon mainly being sourced from atmosphere-lake water exchange, with minor amounts from marine carbonate strata. [ABSTRACT FROM AUTHOR]