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The existing health risk assessment models often rely on total concentrations of contaminants, neglecting cellular absorption, leading to an overestimation of risks due to a lack of toxicological verification. In this study, the content, bioaccessibility, and health risk evaluation of Cr, Ni, Cu, and As in vegetables from mining areas in Southwest China were examined. The cytotoxicity and gastric absorption of heavy metals and underlying mechanisms as well as the toxic mitigation approach after consumption of risky vegetables were explored. Our results showed that the heavy metals in cabbage, celery, and garlic seedlings were within the safety limit, even though grown in contaminated soils. The bioaccessibility of As, Cu, Ni, and Cr in vegetables in the gastric phase is from 6.92% to 81.15%, with mint having the highest bioaccessible concentrations of Cr (32.7 μg/kg), Cu (540.1 μg/kg), and As (103.9 μg/kg). The Hazard Quotient and Hazard Index values of the bioaccessible metals suggested an unacceptable cancer risk. Besides, the vegetable extracts increased cell apoptosis and tight junction disruption. Unexpectedly, the high-risk mint extract with the greatest bioaccessibility didn't cause cytotoxicity but inhibited cell apoptosis and enhanced cellular tight junction, evidenced by the upregulation of Zonula Occludens-1, Occludin , and Claudin 3, and a decrease in cellular heavy metal uptake. Furthermore, the mint extract could alleviate garlic seedling extract-induced cytotoxicity, indicating that the special substance in mint has protective effects. Taken together, special components in vegetables, cellular uptake, and toxicity of heavy metals should be considered in the accurate assessment of health risks. [Display omitted] • Heavy metals in cabbage, celery, and garlic seedling were within the safety limit. • Cabbage, celery, and garlic extracts induced apoptosis and tight junction disruption. • The high-risk mint extract inhibited cell apoptosis and enhanced tight junction. • The mint extract could alleviate the garlic seedling extract-induced cytotoxicity. [ABSTRACT FROM AUTHOR]

• The high water table (HWT) enhances methanotrophic α-diversity, while the low water table (LWT) elevates methanogenic α-diversity. • Methanogens are dominated by methanoregula at the LWT site, and by methanobrevibacter and Methanoregula , and methanosarcina at the HWT site. • Methanotrophs are dominated by methylosinus at the LWT site, and by Methylocystis, methylosinus and methylocapsa at the HWT site. • HWT enhances the stability and complexity of ecological networks of methanotrophs and methanogens. • Temperature-dependent methane emissions vary with water table in the sub-alpine peatland. Methanogens and methanotrophs are important in regulating the peatland carbon cycle. The influence of hydrology on microbiota in different peatlands has been globally documented; however, the hydrological impact on methane-related microbial communities and methane (CH 4) emission remains underexplored in sub-alpine peatlands. Here, seasonal methanogenic and methanotrophic communities, as well as CH 4 emission, were determined at two sites with different water table levels from the Dajiuhu peatland, the largest intact sub-alpine peatland. Methane-related microbial communities varied with water table. A higher methanogenic and lower methanotrophic α-diversity were unveiled in samples with low water table (LWT), a reverse pattern was observed in high water table (HWT). Hydrogenotrophic methanogens dominated in samples with LWT, whereas hydrogenotrophic and aceticlastic methanogens dominated with HWT. Type II methanotrophs were predominant at both sites. Samples with HWT had higher gene copy numbers of methanogens (mcrA) and methanotrophs (pmoA) than those with LWT. Along the peat profile, methanogens and type II methanotrophs were enriched in samples at the depth of 10 - 15 cm and their abundances decreased toward deeper layers. Both type Ia and Ib methanotrophs were abundant in surface samples (0 - 5 cm). The HWT co-occurrence networks of methanogen and methanotroph were more stable and complex in contrast to those in LWT. Soil temperature was an important driver of seasonal variations in CH 4 emission at the LWT sites (0.03 - 1.61 mg m−2 h−1 for bare peat and 0.06 - 4.08 mg m−2 h−1 for peat covered with Sphagnum palustre) and HWT sites (0.25 - 0.78 mg m−2 h−1 for bare peat and 0.42 - 9.60 mg m−2 h−1 for peat covered S. palustre). The water table and vegetation affected the pattern of seasonal CH 4 emission. These results provide new insights in understanding the effect of hydrology on microbial functional groups and CH 4 emission within sub-alpine peatlands. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Sasakia funebris, a member of the lepidopteran family, Nymphalidae (superfamily Papilionoidea) is a rare species and is found only in some areas of South China. In this study, the 15,233bp long complete mitochondrial genome of S. funebris was determined, and harbors the gene arrangement identical to all other sequenced lepidopteran insects. The nucleotide composition of the genome is highly A+T biased, accounting for 81.2%. All protein-coding genes (PCGs) start with typical ATN codons, except for COI which begins with the CGA codon. All tRNAs have a typical clover-leaf secondary structure, except for tRNASer(AGN) , the dihydrouridine (DHU) arm of which forms a simple loop. The S. funebris A+T-rich region of 370bp contains several features common to the Lepidoptera insects, including the motif ATAGA followed by a 19bp poly-T stretch, and two tandem repeats consisting of 18bp repeat units and 14bp repeat units. The phylogenetic analyses of Apaturinae based on mitogenome sequences showed: (S. funebris + Sasakia charonda)+(Apatura metis + Apatura ilia). This result is consistent with the morphological classification. [Copyright &y& Elsevier]

Abstract: Burkholderia glumae causing seedling rot and grain rot of rice was listed as a plant quarantine disease of China in 2007. It''s quite necessary to set up effective detection methods for the pathogen to manage further dispersal of this disease. The present study combined the real-time PCR method with classical PCR to increase the detecting efficiency, and to develop an accurate, rapid and sensitive method to detect the pathogen in the seed quarantine for effective management of the disease. The results showed that all the tested strains of B. glumae produced about 139 bp specific fragments by the real-time PCR and the general PCR methods, while others showed negative PCR result. The bacteria could be detected at the concentrations of 1×104 CFU/mL by general PCR method and at the concentrations below 100 CFU/mL by real-time fluorescence PCR method. B. glumae could be detected when the inoculated and healthy seeds were mixed with a proportion of 1:100. [Copyright &y& Elsevier]

Stormflow runoff is the most important agent for phosphorus (P) input to reservoirs, as the particulates contained in runoff carry a substantial amount of P. The settling process of particulates affects the P content of water, and the distribution of particulates determines the P distribution in reservoir sediment. An understanding of flood impacts on the transport, transition, and accumulation of P in a reservoir is critical to reservoir management. In this study, water samples before and after flooding and sediment samples after flooding were collected from Biliuhe Reservoir in Northeast China. P content and load in the water and P-fractions and particle sizes of the sediments were analyzed. Results showed that total particulate P (TPP) increased sharply from 1.56 to 26.72 t after flooding, whereas dissolved organic P (DOP) decreased markedly from 3.24 to 1.17 t, which was largely caused by biological uptake directly or indirectly before flooding. Orthophosphate (PO 4 3 − ) shared a similar trend with TPP, indicating that PO 4 3 − could be adsorbed onto settling particulates, helping to reduce the reactive P introduced by flooding. Reservoir sediment showed a fining trend downstream and the clay fraction exhibited an obvious correlation with P-fractions, demonstrating that the distribution of particulate matter determined P distribution in the sediment. This study also found that particulates from the largest tributary (Biliu River) were only minimally transported from its reservoir entrance to the dam because of a longer travel distance, while contrastingly, particulates from a smaller tributary (Bajia River) were maximally carried to the dam because of a shorter distance. Our fundings suggests that surface water in the reservoir should be released prior to flooding in order to mitigate control of P in the water, moreover, it is necessary to strengthen the effectiveness of pollutant control projects at the reservoir entrance of the Bajia River. Image 1 • Biological uptake before flood may reduce dissolved organic phosphorus (P) load. • Particulate has slow adsorption of PO 4 3 − during settling. • Abundant iron source in basin is crucial to keep low P content in reservoir water. • The distribution of particulate determined the distribution of P in sediment. • Surface water should be released prior to flood for P control in reservoir. The slow adsorption of P O 4 3 − by particulates during settling has an effect on decreasing the reactive P load. The discharge of water with particulates during the flood season may result in higher retention of reactive P in water. [ABSTRACT FROM AUTHOR]

Riemerella anatipestifer , belonging to Weeksellaceae family Riemerella, is a bacterium that can infect ducks, geese, and turkeys, causing diseases known as duck infectious serositis, new duck disease, and duck septicemia. We collected diseased materials from ducks on a duck farm in China and then isolated and purified a strain of serotype 1 R. anatipestifer named SX-1. Animal experiments showed that SX-1 is a highly virulent strain with an LD 50 value of 101 CFU/mL. The complete genome sequence was obtained. The complete genome sequence of R. anatipestifer SX-1 was 2,112,539 bp; 847 genes were involved in catalytic activity, and 445 genes were related to the cell membrane. The total length of the repetitive sequences was 8746 bp. Four CRISPR loci were predicted in R. anatipestifer strain SX-1, and 4 genomic islands were predicted. Concentration and ultra-high-speed centrifugation were used to extract the outer membrane vesicles of R. anatipestifer SX-1. The OMVs were extracted successfully. Particle size analysis revealed the size and abundance of particles: 147.4 nm, 94.9%; 293.6 nm, 1.1%; 327.2 nm, 1.1%; 397.2 nm, 0.3%; and 371.8 nm, 1.1%. The average size was 173.5 nm. Label-free proteomic technology was used to identify proteins in the outer membrane vesicles. ATCC 11845 served as the reference genome sequence, and 148 proteins were identified using proteomic analysis, which were classified into 5 categories based on their sources. Among them, 24 originated from cytoplasmic proteins, 4 from extracellular secreted proteins, 27 from outer membrane proteins, 10 from periplasmic proteins, and 83 from unknown sources. This study conducted a proteomic analysis of OMVs to provide a theoretical basis for the development of R. anatipestifer OMVs vaccines and adjuvants and lays the foundation for further research on the relationship between the pathogenicity of R. anatipestifer and OMVs. [ABSTRACT FROM AUTHOR]

• Alien dinoflagellates in transoceanic ships might invade inland freshwater ecosystems. • Novel insights from different sampling sites including washing basin. • Combined approach used to detect dinoflagellate cysts in ballast tanks. • Genetic diversity of dinoflagellate cysts exhibited in ballast tank sediments. Ships' ballast water and sediments have long been linked to the global transport and expansion of invasive species and thus have become a hot research topic and administrative challenge in the past decades. The relevant concerns, however, have been mainly about the ocean-to-ocean invasion and sampling practices have been almost exclusively conducted onboard. We examined and compared the dinoflagellate cysts assemblages in 49 sediment samples collected from ballast tanks of international and domestic routes ships, washing basins associated with a ship-repair yard, Jiangyin Port (PS), and the nearby area of Yangtze River (YR) during 2017–2018. A total of 43 dinoflagellates were fully identified to species level by metabarcoding, single-cyst PCR-based sequencing, cyst germination and phylogenetic analyses, including 12 species never reported from waters of China, 14 HABs-causing, 9 toxic, and 10 not strictly marine species. Our metabarcoding and single-cyst sequencing also detected many OTUs and cysts of dinoflagellates that could not be fully identified, indicating ballast tank sediments being a risky repository of currently unrecognizable invasive species. Particularly important, 10 brackish and fresh water species of dinoflagellate cysts (such as Tyrannodinium edax) were detected from the transoceanic ships, indicating these species may function as alien species potentially invading the inland rivers and adjacent lakes if these ships conduct deballast and other practices in fresh waterbodies. Significantly higher numbers of reads and OTUs of dinoflagellates in the ballast tanks and washing basins than that in PS and YR indicate a risk of releasing cysts by ships and the associated ship-repair yards to the surrounding waters. Phylogenetic analyses revealed high intra-species genetic diversity for multiple cyst species from different ballast tanks. Our work provides novel insights into the risk of bio-invasion to fresh waters conveyed in ship's ballast tank sediments and washing basins of shipyards. [Display omitted] [ABSTRACT FROM AUTHOR]

The Yawan Sb deposit is a large deposit located in the Xihe County, Gansu, northwestern China. Ore bodies are hosted in the Triassic limestone and are controlled by the NE- trending faults, occurring as lamellar, lenticular, veined, and lentil. Based on the cutting relationship between veins and mineral assemblages, the ore-forming process can be divided into four stages: I) pyrite + stibnite + milky quartz stage, II) stibnite + pyrite + gray-black cryptocrystalline quartz stage, III) stibnite + calcite + fluorite stage, and IV) clear and colorless calcite stage. The δ34S values (−2.5 ‰ to 5.8 ‰) of sulfides from stage II are similar to those associated with magmatic systems, but significantly different from the values (δ34S = −12.8 ‰ to 18.8 ‰) of pyrites from strata, suggesting that magmatic sulfur was the source for S2− in stage II. The δ34S values (−9.5 ‰ to −7.5 ‰) of stibnites from stage III are depleted in 34S relative to those of stage II, probably due to the increasingly mixing of meteoric water and SO 4 2− from the strata. The Pb isotopes of sulfides from stage II and III (206Pb/204Pb = 17.745–19.176, 207Pb/204Pb = 15.478–15.711, 208Pb/204Pb = 37.7–38.742) show a mixed source of crust and mantle. The δ13C and δ18O values of calcites range from −0.84 ‰ to 3.94 ‰ and from 4.74 ‰ to 13.24 ‰, respectively, indicating that the ore-forming fluids originated from magmatic water, but influenced by water-rock interaction and meteoric water in the late stage. The Sm Nd isochron age of five calcite simples from stage III is 199.9 ± 1.7 Ma (MSWD = 1.6) with initial ε Nd values of −8.4, indicating that Yawan Sb deposit formed in the Late Triassic to Early Jurassic. On the basis of the data obtained in this paper, we consider that the Yawan Sb deposit is a distal magmatic-hydrothermal deposit formed during the transitional tectonic regime from the syn -collision to post-collision. Combined with previous studies, future exploration should focus on the distal magmatic-hydrothermal Sb deposits controlled by faults around concealed granites, and skarn-type deposits also need attention in Yawan-Daqiao district. • The Yawan Sb deposit is a distal magmatic-hydrothermal deposit. • Ore-forming components originally derived from deep magmas. • The dating of calcite intergrown with stibnite indicates that the Yawan Sb deposit was formed at 199.9 Ma. [ABSTRACT FROM AUTHOR]

[Display omitted] • The uranium-supplying capacity of source rock dominated by rock type. • U 0 is the core parameter for classifying/evaluating the uranium-supplying capacity. • Uranium sources are the fundamental prerequisite for uranium sinks. • The "source-to-sink" approach have practical value for uranium deposit exploration. Accurate evaluation of uranium sources and identification of their spatiotemporal correlations with uranium deposits (or sinks) in sedimentary basins are important for exploring sandstone-type uranium deposits. This study examines the source-to-sink system of Mesozoic–Cenozoic sandstone-type uranium deposits in the Qaidam Basin (QB) through a literature review in conjunction with logging and seismic data and yields the following findings. (1) The uranium-supplying capacity of a source rock in the uranium source area depends on primarily its type and to a lesser extent, the tectonic zone where it is located and the episode during which it formed. (2) The initial uranium content, U 0 , is the core parameter for classifying and evaluating the uranium-supplying capacity of a source rock. At U 0 > 1.5 ppm, uranium begins to migrate from a source rock. The uranium variation coefficient, ΔU, and the amount of uranium migration, ΔUt, decrease continuously to –55 % and –5 ppm respectively as U 0 increases up to 9.5 ppm, which suggests that at most 5 ppm of uranium in the source rocks can migrate away. As U 0 increases beyond 9.5 ppm, ΔU and ΔUt fluctuate around –55 % and –7 ppm respectively, which suggests that approximately 7 ppm of the uranium in the source rocks can migrate away. (3) Of the different types of rocks, silicic igneous rocks (including both intrusive and volcanic igneous rocks) and granitic gneisses have the highest uranium-supplying capacity; intermediate igneous rocks and gneisses come second; mafic–ultramafic igneous rocks and the other metamorphic rocks (except granitic gneiss and gneiss) come third. Of the sub-source areas (tectonic zones), the western segment of the Eastern Kunlun and the Qiman Tagh have the highest uranium-supplying capacity; the Central and Southern Altyn Tagh come second; the others come third. (4) Uranium sources are the fundamental prerequisite for the formation of uranium sinks. Other geological factors control the specific formation process of uranium sinks as well as their spatiotemporal distribution patterns. For QB, the most economic and prospective uranium sink, Neogene formations of Gy anticline, was fed by the source areas which had the highest uranium-supplying capacity. This suggests that the Neogene of WEK anticline belt, Quaternary of Kumukol Basin and Qarqan River Basin are the most noteworthy metallogenic prospective areas. The uranium-source evaluation scheme and "source-to-sink" ore exploration approach introduced in this study have practical value for advancing the exploration of uranium deposits in sedimentary basins in northern China and other parts of the world. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To introduce the experience of aeromedical transport of critically burned patients in Northwest China and to explore the time and conditions of transport. Methods: From August 1992 to July 2003, eight sorties of aeromedical transport of critically burned patients in Northwest China were analyzed. Results: Eighteen critically burned patients were safely transported to destination. Their total burn surface areas (TBSA) were 49–95%, and their full-thickness burn surface areas were 41–92%. Escharotomies on the chest and extremities were performed in 6 patients and 28 extremities, respectively. All patients were accompanied by inhalation injury. Among them, tracheostomy was carried out in 12 patients with moderate and severe inhalation injury. Of 18 patients, 4 patients were transported with shock and 14 patients were transported after resuscitation. Conclusion: It is safe to transport critically burned patients after resuscitation. Furthermore, it is also safe to perform aeromedical transport during shock with caution and good preparation. [Copyright &y& Elsevier]