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Heavy metal contamination in marine sediments poses significant ecological risks, particularly in semi-enclosed seas like the Bohai Sea, where limited water exchange exacerbates pollution retention. Heavy metals are persistent, bioaccumulative, and toxic, making their assessment crucial for environmental management. This study investigated the spatial distribution, seasonal dynamics, and potential ecological risks of heavy metal contamination in the central Bohai Sea, with an emphasis on regulatory interventions and anthropogenic influences. The annual average concentrations of Cu, Zn, Pb, Cd, Hg and As in surface sediments were 15.951, 32.556, 15.234, 0.250, 0.028 and 2.628 mg/kg, respectively, all below China’s Class I Marine Sediment Quality Standards. Seasonal variations revealed peak concentrations in August for Zn, Pb, Hg and As, likely driven by increased terrestrial inputs and hydrodynamic conditions. Cd exhibited the highest ecological risk, with a single-factor risk index exceeding 30 in May, followed by Hg, Pb, Cu, As and Zn. The comprehensive pollution index remained below 5 across all seasons, indicating overall low pollution levels. However, localized exceedances of Class I standards for Cu, Pb and Cd were observed, particularly in summer and autumn. Spatially, metal concentrations were higher near industrial and riverine discharge zones, with anthropogenic sources such as petrochemical industries, aquaculture, and urban runoff contributing significantly. This study highlighted seasonal and spatial heterogeneity in heavy metal contamination in the central Bohai Sea, emphasizing the influence of industrial activities and hydrodynamic processes. While overall pollution levels were low, the high ecological risk associated with Cd underscores the need for continued monitoring and targeted pollution control measures. Strengthening enforcement of industrial regulations, improving sediment management, and addressing seasonal fluctuations in pollutant inputs were critical for mitigating future risks. These findings provided a scientific foundation for sustainable marine environmental management and policy formulation in the Bohai Sea.

Abundant carbon was identified on Mercury by MESSENGER, which is interpreted as the remnant of a primordial graphite flotation crust, suggesting that the magma ocean and core were saturated in carbon. We re-evaluate carbon speciation in Mercury’s interior in light of the high pressure-temperature experiments, thermodynamic models and the most recent geophysical models of the internal structure of the planet. Although a sulfur-free melt would have been in the stability field of graphite, sulfur dissolution in the melt under the unique reduced conditions depressed the sulfur-rich liquidus to temperatures spanning the graphite-diamond transition. Here we show it is possible, though statistically unlikely, that diamond was stable in the magma ocean. However, the formation of a solid inner core caused diamond to crystallize from the cooling molten core and formation of a diamond layer becoming thicker with time. A diamond layer that becomes thicker with time is generated from carbon exsolution at the core-mantle boundary of Mercury, owing to cooling of its metallic core and potentially the silicate magma ocean.

Seismological and geodetic data indicate that the lunar core-mantle boundary (CMB) exhibits a well-defined low-velocity zone (LVZ) with a combination of anomalous seismic velocities and density that remain unexplained. Here, in-house high-pressure experiments simulating the interaction between mantle olivine and core iron at CMB conditions in conjunction with thermodynamic modeling demonstrate reactive formation of dense iron-rich magnesiowüstite [Mw, (Fe,Mg)O], a hitherto unrecognized lunar mineral. In-situ synchrotron ultrasonic measurements show that the seismic velocities and density of Mw, when incorporated in realistic proportions of ~5–15 wt% with mantle olivine plus minor silicate melt match the observed LVZ properties. Oxygen exsolution from core metal during cooling is the most likely driver of Mw formation, quantitatively yielding the required Mw proportions in the LVZ. These results suggest that core-mantle reactions can generate magnesiowüstite through oxidation of iron metal, offering a blueprint for the expected seismic properties of the CMB regions of rocky bodies that experience mantle oxidation after core formation. High-pressure experiments show that reactions between the Moon’s core and mantle form iron-rich magnesiowüstite, explaining the mysterious low-velocity zone at the lunar core– mantle boundary and revealing how core chemistry shapes planetary interior

Rapeseed polyphenols have cardiovascular protective effects. Sinapine, one main rapeseed polyphenol, possesses antioxidative, anti-inflammatory, and antitumor properties. However, no research has been published about the role of sinapine in alleviating macrophage foaming. This study aimed to reveal the macrophage foaming alleviation mechanism of sinapine by applying quantitative proteomics and bioinformatics analyses. A new approach was developed to retrieve sinapine from rapeseed meals by using hot-alcohol-reflux-assisted sonication combined with anti-solvent precipitation. The sinapine yield of the new approach was significantly higher than in traditional methods. Proteomics was performed to investigate the effects of sinapine on foam cells, and it showed that sinapine can alleviate foam cell formation. Moreover, sinapine suppressed CD36 expression, enhanced the CDC42 expression, and activated the JAK2 and the STAT3 in the foam cells. These findings suggest that the action of sinapine on foam cells inhibits cholesterol uptake, activates cholesterol efflux, and converts macrophages from pro-inflammatory M1 to anti-inflammatory M2. This study confirms the abundance of sinapine in rapeseed oil by-products and elucidates the biochemical mechanisms of sinapine that alleviates macrophage foaming, which may provide new perspectives for reprocessing rapeseed oil by-products.

An intensive field campaign was carried out from December 2022 to March 2023 at six different sites across five major cities (Xi’an, Baoji, Xianyang, Weinan, and Hancheng) in the Guanzhong Basin, China, covering most of the heating period there, which is characterized by high PM2.5 pollution levels. During the campaign, the mean PM2.5 concentrations at these sites exceeded the 24 h PM2.5 standard (75 μg m−3), except the site at Hancheng, with mean PM2.5 concentrations of 57.8 ± 32.3 μg m−3. The source apportionment of PM2.5 varied significantly across sites, with vehicle exhaust being the dominant source at urban sites located in Xi’an and Baoji, coal combustion at suburban sites in Hancheng, and comparable contribution from coal combustion and industrial emissions at suburban sites in Xianyang and Weinan. Compared with clean condition, the contribution of vehicle exhaust and secondary inorganic sources (SIs) were largely enhanced during heavy PM2.5 pollution periods, while the contribution from biomass burning (BB) and dust decreased significantly at all sites. Combined with an analysis of meteorological parameters, the study further found that higher contributions of SIs and heavy PM2.5 pollution were generally associated with higher relative humidity (RH). In addition, higher PM2.5 concentrations at suburban sites were related to lower wind speeds, which could be explained by the stagnant condition favoring the accumulation of local emissions as well as the formation of secondary pollutants. In contrast, at urban sites (e.g., Xianyang), higher PM2.5 concentrations were more associated with the strong influence of vehicle exhaust at slightly higher wind speeds.

The composition and digestion of phospholipid-rich foods have important effects on the health of the body. Herein, a model-assisted liquid chromatography coupling mass spectrometry (LC-MS) method was established to analyze the phosphatidylcholine (PC) and lyso-phosphatidylcholine (LPC) species in krill oil before and after digestion. According to the confirmed PC and LPC species in the IDA (information dependent acquisition) results, three categories of mathematical models were set up, involving the retention time (RT), carbon number and unsaturation degree of the fatty acyl chain. All of the regression coefficient values (R2) were greater than 0.90, showing satisfactory fitting results. On this basis, using the computationally created precursor ion mass of PC and LPC species, 12 extra PC species and 4 LPC species were found in the SWATH (sequential windowed acquisition of all theoretical fragment ions) results. The PC and LPC compositions in the final digestive products had obvious differences among the different krill oils with different phospholipid content. Furthermore, more than half of the LPC species in the final digestive products were newly generated, indicating that LPC was one of basic constituents in the digestive products of krill oil. In conclusion, model-assisted hybrid IDA and SWATH acquisition has excellent detection performance, contributing to deep studies of the formations and functions of phospholipids.

Localized intestine inflammation could induce short-term increases in colonic oxygenation and leads to increases in the aerobic bacteria population and reduction in the anaerobic bacteria population by changing the intestinal environment. However, the mechanisms involved and the associated functions of intestinal anaerobes in gut health still remain unclear. Here, we found that early-life depletion of gut microbiota exacerbated later colitis, while mid-life microbiota depletion showed partially reduced colitis. Notably, we observed that early-life gut microbiota depletion confers susceptibility to ferroptosis in colitis. In contrast, restitution of early-life microbiota conferred protection against colitis and inhibited ferroptosis triggered by gut microbiota dysbiosis. Similarly, colonization with anaerobic microbiota from young mice suppressed colitis. These results may attribute to high abundance of plasmalogen-positive (plasmalogen synthase [PlsA/R]-positive) anaerobes and plasmalogens (one of the common ether lipids) in young mice but reduced abundance in the development of inflammatory bowel disease. Early-life anaerobic bacteria elimination also resulted in the aggravation of colitis, while this aggravation phenotype was reverted by plasmalogen administration. Interestingly, plasmalogens inhibited ferroptosis triggered by microbiota dysbiosis. We further find that the alkenyl-ether group of plasmalogens was critical to colitis prevention and ferroptosis inhibition. These data point to one of the mechanisms by which the gut microbiota controls susceptibility to colitis and ferroptosis early in life via microbial-derived ether lipids.

Marbled flounder ( Pseudopleuronectes yokohamae ) is becoming a commercially important flatfish species in Northeast Asia due to its strong environmental adaptability and excellent nutritional value. However, no high-quality marbled flounder reference genome was reported to date, which greatly limits the studies of evolutionary and functional genomics. Here, we reported the first gap-free T2T genome in flatfish (marbled flounder), with length of 582.73 Mb (contig N50: 26.29 Mb) combing short reads, PacBio HiFi long reads, ONT ultra-long reads, and Hi-C data. All of the genome sequences were assembled onto 24 chromosomes, and 48 telomeres were identified on both ends of all chromosomes. 99.29% complete BUSCOs were identified, demonstrating a high level of completeness. The average mapping ratio of short reads, PacBio HiFi reads, and ONT ultra-long reads aligned to the genome was more than 99.89%. 121.02 Mb repeating elements and 22,778 protein-coding genes were identified in the genome assembly. These results provide valuable resources for the evolutionary genomics research and the identification of key candidate genes for economic traits in marbled flounder.

Marbled flounder (Pseudopleuronectes yokohamae) exhibits a distinct female growth advantage and an XX/XY sex determination system. To exploit these traits, we investigated 17α-methyltestosterone (MT)-induced transcriptomic changes in gonadal tissue with the goal of generating pseudomale XX broodstock for all-female fry production. Full-sibling diploid juveniles (60 days post-hatching, dph) were fed diets containing 0 (control), 0.5, or 2 mg/kg MT for 120 days, followed by a 60-day recovery period on a commercial diet prior to sampling. Testicular transcriptomes were profiled via high-throughput sequencing, and key differentially expressed genes were validated using qPCR. Both MT treatments resulted in 100% masculinization. Testicular transcriptome analysis revealed 972 differentially expressed genes (DEGs) (180 up, 792 down) in the 0.5 mg/kg MT-treated males (MT05M) compared to the control males, and 1245 DEGs (842 up, 403 down) in the 2 mg/kg MT group (MT20M). Gene Ontology terms were enriched for extracellular space and signaling receptor regulator activity. KEGG pathway analysis indicated significant enrichment in neuroactive ligand–receptor interaction, ovarian steroidogenesis, and TGF-β signaling. qPCR confirmed significant downregulation (p < 0.05) of sox17, bmp4, and smad6, while dmrt1 was downregulated only in the MT20M group. These findings demonstrate that MT effectively masculinizes P. yokohamae by modulating key sex-related genes and signaling pathways, providing a transcriptomic foundation and potential mechanistic insights for optimizing pseudomale induction to enable all-female aquaculture production.

Yellowtail kingfish has emerged as one of the most promising marine fishes for aquaculture in China because it is tasty, fast growing, and has high economic value. To investigate the tolerance and adaptability to hypoxia of farmed yellowtail kingfish, juveniles were exposed to hypoxia (3.0 ± 0.5 mg/L) for 5 days and then returned to normoxia (7.5 ± 0.5 mg/L) for another 5 days. Using tissue sections and high-throughput sequencing technology, we investigated the histological, microecological, transcriptomic, and physiological adaptation mechanisms of yellowtail kingfish. The results showed that hypoxia increased the gill lamellae length and spacing, which were reversible post-reoxygenation. At the genus level, the relative abundances of Prevotella , Bacteroides , Roseburia , and Blautia in the gastrointestinal tract increased under hypoxia and were maintained post-reoxygenation. The liver transcriptome revealed that, compared with normoxia group, the different expression genes (DEGs) were mainly enriched in Steroid biosynthesis and PPAR signaling pathways in hypoxia group. Compared with normoxia group, the DEGs were mainly enriched in Ribosome biogenesis in eukaryotes, Steroid biosynthesis, Fatty acid biosynthesis, and PPAR signaling pathways in reoxygenation group. Furthermore, compared with hypoxia group, the DEGs were mainly enriched in Ribosome biogenesis in eukaryotes and Ribosome pathways in reoxygenation group. In contrast to normoxia, of the key genes of the PPAR signaling pathway, FABP4 was significantly downregulated, and SCD-1 and FATP were significantly upregulated. These findings indicated reduced lipid deposition and increased lipid decomposition in liver under hypoxia. The genes including PPARα , SCD-1 , ANGPTL4 , and FASN were significantly upregulated in lipid metabolism-related pathways, which indicated that lipid metabolism activity was more vigorous during reoxygenation. In contrast to the hypoxia group, almost all of the genes involved in Ribosome biogenesis in eukaryotes and Ribosome pathways for protein processing were significantly upregulated during reoxygenation; this is probably related to the clearance of misfolded proteins and the folding of the new proteins repairing there is damage to the body. The present results shed light on the possible synergetic function of lipid metabolism, protein repairment and synthesis, and gastrointestinal microbiota in resistance and homeostasis maintenance of yellowtail kingfish coping with hypoxic stress in aquaculture.