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The Arctic region is experiencing more rapid climate changes than the other parts of the world and serves as a sink for semi‐volatile persistent organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), which can be utilized as molecular markers for pyrogenic carbon, such as black carbon (BC). As the sea ice retreats and increased terrestrial inputs with widespread wildfires, the PAH concentrations in the Arctic Ocean are rising. In this study, the sources and fates of PAHs together with BC in surface sediments from the East Siberian Arctic Shelf (ESAS) were analyzed. Positive matrix factorization (PMF) elucidated a mixed petrogenic and pyrogenic sources and distinct PAH fates associated with diverse input pathways including coastal permafrost erosion contribution (∼30%), petrogenic‐related emission (∼34%), fossil fuel combustion (∼26%), and biomass burning (∼10%). Correlation analysis indicated that BC plays a key role in affecting the behavior and fates of PAHs. In the Chukchi Sea, PAHs are closely associated with soot‐BC, whereas in the Laptev Sea (LS) and west East Siberian Sea (W‐ESS), they exhibit a coupling process with char‐BC. The presence of these carbonaceous materials in the sediments of CS is likely influenced by atmospheric deposition and biological activity, whereas the LS and W‐ESS regions are mainly affected by long‐distance river transport and direct deposition from coastal permafrost. As global warming continues, permafrost thawing induces the remobilization and retranslocation of PAHs, thereby becoming a significant PAH contributor and input pathway in the rapidly changing Arctic coastal margin. Plain Language Summary: The Arctic region is experiencing rapid climate changes, such as reducing sea ice, thawing permafrost, and increasing wildfires. These changes are raising the levels of semi‐volatile pollutants such as polycyclic aromatic hydrocarbons (PAHs) in the Arctic coastal margins, with the potential for the region to become a significant reservoir of sedimentary PAHs. In our study, we examined the large‐scale distribution and fates of PAHs and black carbon (BC) across the East Siberian Arctic Shelf (ESAS), the world's largest shelf system. We discovered that PAHs have mixed sources, including both petrogenic and pyrogenic origins. We also observed differences in how PAHs were transported and sequestrated in coastal versus open sea areas. In the western ESAS, PAHs and BC are mainly influenced by terrestrial inputs such as river discharge and coastal permafrost erosion. In contrast, in the eastern open‐sea regions, they are primarily constrained by atmospheric transport and biological activity are the primary influencing factors. The significant emissions from thawing permafrost along the coasts highlight the growing importance of permafrost‐related erosion as a significant contributor of PAHs in the Arctic Ocean, particularly in the context of future warming. Key Points: Sedimentary polycyclic aromatic hydrocarbons (PAHs) in the East Siberian Arctic Shelf (ESAS) have a mixture of petrogenic and pyrogenic sources with distinct input pathwaysPermafrost erosion serves as a significant input pathway and PAHs contributor in the rapidly changing Arctic coastsBlack carbon plays a key role in the behavior and sequestration of pyrogenic PAHs in the Arctic coastal margins [ABSTRACT FROM AUTHOR]

The Dahongshan Fe‐Cu (‐Au) deposit is a superlarge deposit in the Kangdian metallogenic belt, southwestern China, comprising approximately 458 Mt of Fe ores (40% Fe) and 1.35 Mt Cu. Two main types of Fe‐Cu (‐Au) mineralization are present in the Dahongshan deposit: (1) early submarine volcanic exhalation and sedimentary mineralization characterized by strata‐bound fine‐grained magnetite and banded Fe‐Cu sulfide (pyrite and chalcopyrite) hosted in the Na‐rich metavolcanic rocks; (2) late hydrothermal (‐vein) type mineralization characterized by Fe‐Cu sulfide veins in the hosted strata or massive coarse‐grained magnetite orebodies controlled by faults. While previous studies have focused primarily on the early submarine volcanic and sedimentary mineralization of the deposit, data related to late hydrothermal mineralization is lacking. In order to establish the metallogenic age and ore‐forming material source of the late hydrothermal (‐vein) type mineralization, this paper reports the Re‐Os dating of molybdenite from the late hydrothermal vein Fe‐Cu orebody and H, O, S, and Pb isotopic compositions of the hydrothermal quartz‐sulfide veins. The primary aim of this study was to establish the metallogenic age and ore‐forming material source of the hydrothermal type orebody. Results show that the molybdenite separated from quartz‐sulfide veins has a Re‐Os isochron age of 831 ± 11 Ma, indicating that the Dahongshan Fe‐Cu deposit experienced hydrothermal superimposed mineralization in Neoproterozoic. The molybdenite has a Re concentration of 99.7–382.4 ppm, indicating that the Re of the hydrothermal vein ores were primarily derived from the mantle. The δ34S values of sulfides from the hydrothermal ores are 2‰–8‰ showing multi‐peak tower distribution, suggesting that S in the ore‐forming period was primarily derived from magma and partially from calcareous sedimentary rock. Furthermore, the abundance of radioactive Pb increased significantly from ore‐bearing strata to layered and hydrothermal vein ores, which may be related to the later hydrothermal transformation. The composition of H and O isotopes within the hydrothermal quartz indicates that the ore‐forming fluid is a mixture of magmatic water and a small quantity of water. These results further indicate that the late hydrothermal orebodies were formed by the Neoproterozoic magmatic hydrothermal event, which might be related to the breakup of the Rodinia supercontinent. Mantle derived magmatic hydrothermal fluid extracted ore‐forming materials from the metavolcanic rocks of Dahongshan Group and formed the hydrothermal (‐vein) type Fe‐Cu orebodies by filling and metasomatism. [ABSTRACT FROM AUTHOR]

Background and Purpose. Previously, we found that insulin-like growth factor-1 (IGF-1) levels in the infarct cortex in the acute phase of distal middle cerebral artery occlusion (dMCAO) rats are increased by intravenous infusion of allogeneic mesenchymal stem/stromal cells (MSCs). CD68+ microglia and NeuN+ neurons are part, but not all, of the sources of IGF-1. The present study is aimed at exploring the respective contributions of brain endogenous Iba-1+ microglia, GFAP+ astrocytes, infiltrated neutrophils, lymphocytes and monocytes/macrophages, and peripheral circulation, to the increased IGF-1 level in the infarct cortex after MSC infusion. Materials and Methods. Ischemic brain injury was induced by dMCAO in Sprague-Dawley rats. The transplantation group received MSC infusion 1 h after dMCAO. Expression of IGF-1 in GFAP+ astrocytes, Iba-1+ microglia/macrophages, CD3+ lymphocytes, Ly6C+ monocytes/macrophages, and neutrophil elastase (NE)+ neutrophils was examined to determine the contribution of these cells to the increase of IGF-1. ELISA was performed to examine IGF-1 levels in blood plasma at days 2, 4, and 7 after ischemia onset. Results. In total, only 5-6% of Iba-1+ microglia were colabeled with IGF-1 in the infarct cortex, corpus callosum, and striatum at day 2 post-dMCAO. MSC transplantation did not lead to a higher proportion of Iba-1+ cells that coexpressed IGF-1. In the infarct cortex, all Iba-1+/IGF-1+ double-positive cells were also positive for CD68. In the infarct, corpus callosum, and striatum, the majority (50-80%) of GFAP+ cells were colabeled with ramified IGF-1 signals. The number of GFAP+/IGF-1+ cells was further increased following MSC treatment. In the infarct cortex, approximately 15% of IGF-1+ cells were double-positive for CD3. MSC treatment reduced the number of infiltrated CD3+/IGF-1+ cells by 70%. In the infarct, few Ly6C+ monocytes/macrophages or NE+ neutrophils expressed IGF-1, and MSC treatment did not induce a higher percentage of these cells that coexpressed IGF-1. The IGF-1 level in peripheral blood plasma was significantly higher in the MSC group than in the ischemia control group. Conclusion. The MSC-mediated increase in IGF-1 levels in the infarct cortex mainly derives from two sources, astrocytes in brain and blood plasma in periphery. Manipulating the IGF-1 level in the peripheral circulation may lead to a higher level of IGF-1 in brain, which could be conducive to recovery at the early stage of dMCAO. [ABSTRACT FROM AUTHOR]

Successful isolation of 15 compounds from Polygonti rhizome was obtained by an efficient technique combined with macroporous resin column chromatography pretreatment and three different modes of high‐speed counter‐current chromatography for the first time. For the pretreatment, AB‐8 resin was applied to remove the polysaccharides and enrich four different parts (samples I, II, III, and IV) by polarities. For the separation, sample I was separated by pH‐zone‐refining counter‐current chromatography and seven cycle recycling mode high‐speed counter‐current chromatography, yielding four alkaloids (1‐‐4); samples II–IV were further separated by the conventional high‐speed counter‐current chromatography, yielding seven flavonoids (5–10, 12), one steroid saponin (11), and three terpenoids (13–15). Finally, the isolates were assayed for their anti‐inflammatory activities against nitric oxide production with compounds 5, 9–10, 13 showing significant anti‐inflammatory activities, IC50 values which were 13.0, 16.2, 17.1, and 14.7 μM, respectively, while others showing moderate and weak anti‐inflammatory activities, respectively. [ABSTRACT FROM AUTHOR]

In this study, a novel polymer‐based solid acid catalyst was prepared by free radical polymerization of N, N′‐methylenebisacrylamide (MBA) and allyl sodium sulfonate (SAS), followed by acidifying of diluted hydrochloric acid. The prepared solid acid was fully characterized by FTIR, solid‐state 13C‐NMR, TGA, XPS, element analysis, and SEM. In addition, the prepared solid acid poly(MBA‐SAA) was used as a catalyst to extract diosgenin from Dioscorea zingiberensis C.H.Wright (DZW) under solvethermal condition using ethanol as a solvent. And the optimal conditions of temperature (104.02°C), alcoholysis time (5.87 h) and solid acid dosage (0.39 g), were obtained by response surface analysis based on the results of single factor experiments. The yield of diosgenin (14.53%) obtained in the alcoholysis is higher than that of the traditional sulfuric acid hydrolysis method. The alcoholysis products were analyzed by high performance liquid chromatography‐mass spectrometry (LC–MS) and UV–vis, respectively. The results showed that the solid acid with higher catalytic activity and good reusability can replace sulfuric acid to extract diosgenin, which has a great potential for the clean production of diosgenin in industry. [ABSTRACT FROM AUTHOR]