[Spatiotemporal Distribution and Source Analysis of Heavy Metals in Surface Sediments in Lake Ulansuhai Based on PCA-APCS-MLR Model].

To explore the spatial and temporal distribution characteristics of heavy metals in the surface sediments of lakes in cold regions during ice-sealing and non-ice-sealing periods, we analyzed the potential ecological risk degree and the pollution sources. A total of 20 sampling sites in Lake Ulansuhai in cold regions were collected from 2020 to 2021, and 120 surface sediment samples were collected during different periods. The contents of As, Cd, Cr, Cu, Ni, Pb, Zn, and Hg were determined. Correlation analysis, principal component analysis, and the absolute factor score-multiple linear regression (APCS-MLR) receptor model were used to trace the source of heavy metal pollution. The results showed that:① the distribution of heavy metals in lake surface sediments was different between the ice-sealing period and the non-ice-sealing period. The distribution of heavy metals during the ice-sealing period was higher in the north and lower in the south. Cd and Hg were mainly distributed in the central and southern lakes during the non-glacial period. ② Hg, Cd, and As were moderately polluted, and Ni was mildly polluted in the surface sediments of the lake. The overall performance was at a high risk level, and the pollution level during the non-ice-sealing period was higher than that during the ice-sealing period. The main environmental risk factors were Hg and Cd, which showed high risk and moderate risk, respectively. ③ The sources of heavy metals in lake surface sediments were mainly industrial sources from mining and transportation, agricultural sources, and natural sources. As, Ni, Pb, and Hg were mainly affected by industrial sources, with contribution rates of 62.67%, 75.31%, 77.47%, and 80.11%, respectively. The main sources of Cu and Zn were natural sources, and Cd was greatly affected by agricultural sources. The contribution rate was 81.57%. The source of Cr was mainly affected by natural factors, and the influence of human activities and unknown sources require further attention.

Influence of environmental factors on changes in the speciation of Pb and Cr in sediments of Wuliangsuhai Lake, during the ice-covered period.

Ecological pollution caused by heavy metals released from sediments is a worldwide concern. However, the effect of changes in sediment speciation on their release of heavy metals has not been adequately reported. In this study, the research focused on Pb and Cr in the ice period of Wuliangsuhai. This study analyzed changes in the sediment speciation of Pb and Cr before and after a release experiment using four risk assessment methods while varying the temperature, pH, and salinity of the water column. The results indicated that the total concentration of Pb ranged from 11.17 to 24.25 mg/kg, while for Cr it ranged from 42.26 to 69.68 mg/kg. Both elements exhibited mild contamination. The release of Pb and Cr from sediments increases with increasing water temperature, mainly due to the conversion of the residual fraction of Pb to the Fe-Mn oxide fraction and Cr converting more residual fraction to the organic matter and sulfide fraction. The release of sediment Pb and Cr decreased with increasing pH, with Pb converting more acid extractable fraction to the residual fraction and Cr converting more organic matter and sulfide fraction to the residual fraction. In contrast, the release of Pb and Cr increased and then decreased with increasing salinity. For Pb, the acid extractable fraction was more susceptible to conversion to the residual fraction by environmental influences, whereas for Cr, the organic matter and sulfide fraction were susceptible to conversion to the residual fraction.

Protective effect of alirocumab, a PCSK9 inhibitor, on the sciatic nerve of rats with diabetic peripheral neuropathy.

Dyslipidemia has been considered a risk factor for diabetic peripheral neuropathy. Proprotein convertase subtilisin-like/Kexin 9 inhibitor (PCSK9) inhibitors are a new type of lipid-lowering drug currently in clinical use. The role of PCSK9 in diabetic peripheral neuropathy is still unclear. In this study, the effect of alirocumab, a PCSK9 inhibitor, on the sciatic nerve in rats with diabetic peripheral neuropathy and its underlying mechanisms were investigated. The diabetic peripheral neuropathy rat model was established by using a high-fat diet combined with streptozotocin injection, and experimental subjects were divided into normal, diabetic peripheral neuropathy, and alirocumab groups. The results showed that Alirocumab improved nerve conduction, morphological changes, and small fiber deficits in rats with DPN, possibly related to its amelioration of oxidative stress and the inflammatory response.

Noninvasive screening of fetal RHD genotype in Chinese pregnant women with serologic RhD-negative phenotype.

BACKGROUND: Noninvasive fetal RHD genotyping has been provided to nonimmunized RhD-negative pregnant women to guide anti-D prophylaxis. Among the Chinese, more than 30% of the RhD-negative phenotype is associated with variant RHD alleles, which would limit the accuracy of fetal RHD status prediction; thus, more targeting and proper programs need to be developed. STUDY DESIGN AND METHODS: Fluorescence quantitative polymerase chain reaction PCR (qPCR) or Sanger sequencing on all RHD exons was used to detect maternal RHD genotypes. For pregnant women with RHD*01N.01 or RHD*01N.03 alleles, the presence of RHD exons 5 and 10 in cell-free DNA was determined by qPCR. For pregnant women with the RHD(1227G>A) allele, high-throughput sequencing on exon 9 of the RHD gene and RHCE gene was used to predict fetal RhD phenotype. RESULTS: Among 65 cases of Chinese pregnant women with the serologic RhD-negative phenotype, three major genotypes were identified: RHD*01N.01/RHD*01N.01 (61.5%), RHD*01N.01/RHD(1227G>A) or RHD*01N.03/RHD(1227G>A) (20%), and RHD*01N.01/RHD*01N.03 (13.8%), along with three cases of minor genotypes (4.6%). For 43 pregnant women with the RHD*01N.01 or RHD*01N.03 alleles, qPCR on maternal cell-free DNA yielded a 98.5% (42/43) accuracy rate and 100% successful prediction rate. High-throughput sequencing was successfully used to predict fetal RhD phenotypes for 13 pregnant women with RHD(1227G>A). CONCLUSION: On the basis of maternal RHD genotyping, fetal genotyping through qPCR or high-throughput sequencing can improve the accuracy and success rate of prenatal fetal RhD phenotype prediction among Chinese pregnant women. It plays a potential role in guiding anti-D prophylaxis and pregnancy management in Chinese pregnant women.

Distributions of total mercury and methylmercury and regulating factors in lake water and surface sediment in the cold-arid Wuliangsuhai Lake region.

This study aimed to understand the occurrence of mercury in the water environment of typical cold and arid lakes and the regulating environmental factors. Water and surface sediment samples were collected from July to August, 2022 in the Wuliangsuhai Lake region for the analysis of total mercury (THg) and total methylmercury (TMeHg). Lake water THg and TMeHg ranged between 19.20 ~ 668.10 and 0.10 ~ 11.40 ng/L, respectively, exceeding China's environmental quality standards and contents of other lakes and reservoirs in China and other areas. Surface sediments showed lower mean THg and TMeHg of 261.85 and 0.18 µg/kg, respectively, with the former significantly exceeding the background value of Inner Mongolia and unpolluted natural lakes but lower than those of lakes affected by human factors, such as aquaculture. Sediments showed relatively low methylation and TMeHg (0.01-0.21%) concentrations. Correlation analysis identified salinity, total dissolved solids, conductivity, and redox potential as important factors affecting mercury speciation in water, whereas those in surface sediments were organic matter, pH, and total iron content. This study conducted preliminary research on the different species of Hg in Wuliangsuhai Lake water environment, which can provide scientific evidence for the specific treatment of Hg pollution in agriculture, or industry and other related fields. Our results suggest that upstream and downstream regulatory agencies should strengthen the regulation of agricultural and industrial production, moderately reduce human activities, and reduce the use of mercury-rich substances such as pesticides.

Characterization of nitrogen and phosphorus at the ice-water-sediment interface and the effect of their migration on overlying water quality in Daihai Lake (China) during the freezing period.

Approximately one-third of the year, Daihai Lake experiences freezing conditions. During this period, the primary mechanisms that impact the quality of the lake water quality include the freezing of nutrients by the ice sheet and the migration of nutrients between the ice, water, and sediment. The present investigation involved the collection of samples of ice, water, and sediment, followed by the utilization of the thin film gradient diffusion (DGT) technique to and explore the distribution and migration of diverse nitrogen (N) and phosphorus (P) forms at the interface of ice, water and sediment. The findings indicate that the freezing process led to the precipitation of ice crystals, which in turn caused the migration of a significant proportion (28-64 %) of nutrients to the subglacial water. The predominant constituents of N and P in subglacial water, were NO3--N and PO43--P, which constituted 62.5-72.5 % of total N (TN) and 53.7-69.4 % of total P(TP). Respectively, with increasing depth, the TN and TP of sediment interstitial water increased. The sediment in the lake acted as a source of PO43--P and NO3--N while acting as a sink or NH4+-N. Soluble reactive P (SRP) flux and NO3--N flux were responsible for 76.5 % and 2.5 % of the P and N present in the overlying water. Additionally, it was observed that 60.5 % of the NH4+-N flux in the overlying water was absorbed and subsequently deposited in the sediment. The presence of soluble and active P in the ice sheet could play a crucial role in the regulation of sediment release of both SRP and NH4+-N. Additionally, the presence of high nutritional salts and the concentration of nitrate nitrogen in the overlying water would certainly increase the pressure of the water environment. Endogenous contamination must be urgently controlled.

Resupply, diffusion, and bioavailability of Hg in paddy soil-water environment with flood-drain-reflood and straw amendment.

Mercury (Hg) poses a significant risk in paddy fields, particularly when it is converted to methylmercury (MeHg) and accumulates in rice. However, the bioavailability and resupply kinetics of Hg in the paddy soil-water environment are not well understood. In this study, the diffusive gradients in thin films (DGT) and the 'DGT-induced fluxes in sediments' model (DIFS) were first adopted to investigate the Hg resupply kinetics, diffusion fluxes and bioavailability in a paddy environment subjected to flood-drain-reflood treatment and straw amendment. Our results show that although the straw amendment limited the bioavailability of Hg (38.2%-47.9% lower than control) in porewater by decreasing its resupply capacity, especially with smaller straw particles, the net production of MeHg in paddy fields was significantly increased after straw amendment (73.5%-77.9% higher than control). The results of microbial sequencing indicate that enhanced methylators (e.g., family Geobacter) and non-Hg methylators (e.g., Methanosarcinaceae) played a crucial role in MeHg production following straw amendment. Moreover, Hg-containing paddy soils generally tend to release Hg into the overlying water, while drain-reflood treatment changes the direction of Hg diffusion fluxes in the paddy soil-water interface. The drainage-reflooded treatment decreases the Hg reactive and resupply capacity of the paddy soil, thereby hindering the release of Hg from soil into overlying water during the early stages of reflooding. Overall, this study provides novel insights into the behavior of Hg in paddy soil-water surface microlayers.

The fate of photoreduction of Hg(II) in aqueous solution by aged microplastic particles and their leached DOM.

The transformation of Hg(II) and Hg(0) in aqueous systems governs the speciation and biogeochemical cycling of Hg. However, with the increasing amount of microplastics in the aqueous environment, little is known about the different effects of microplastic particles and their leached DOM on the photoreduction of Hg(II) to Hg(0) after long-term photoaging. In this study, we found that aged microplastic particles significantly inhibited the photoreduction efficiency (6.40-15.64 %) of Hg(II) compared to the control without any microplastic (31.02 %) and pristine microplastic particles (9.95-34.10 %). This inhibition was due to the adsorption of Hg by the microplastic particles, which decreased the amount of available Hg(II) (Hg(II)RED) that could participate in the photoreduction reaction. The characteristics of aged microplastic particles also indicated rougher surfaces and more oxygen-containing functional groups after photoaging, which may enhance their adsorption capacity compared to pristine microplastic. Interestingly, the photoreduction efficiency of Hg(II) was 11.58-53.28 % higher in the presence of microplastic leach DOM compared to the control. With increasing age, the microplastic leach DOM obviously promotes the photoreduction of Hg(II). Free radical inhibition and electron paramagnetic resonance spectra demonstrated that O2- in microplastic leach DOM contributed to the photoreduction of Hg(II) under light irradiation. Moreover, X-ray absorption near edge structure analyses demonstrated that microplastic leach DOM produced Hg(I) as the primary photoproduct, accounting for 43.17 % of the total Hg in the photoreaction solution and likely reducing it to Hg(0). This study provides novel insights into forecasting the synthesized risks of microplastic aging in the biogeochemical cycle of Hg within aqueous environments.

Targeting ROR1 inhibits glucocorticoid-induced gastric cancer growth.

Glucocorticoids are commonly used in clinic but are also a double-edged sword. While treating tumors, they are reported to promote tumor growth and metastasis. To explore the role and elucidate the mechanism of dexamethasone in promoting tumor growth and metastasis, we detected the levels of cortisol and adrenocorticotropic hormone (ACTH) in peripheral blood of patients with gastric cancer, and immunohistochemical staining was used to detect the expression of ROR1 in the surgically resected gastric cancer samples. The levels of cortisol and ACTH in peripheral blood of patients with stage III and IV gastric cancer were higher than those of patients with stage I/II gastric cancer. Dexamethasone up-regulated the ROR1 level on gastric cancer cell lines in a concentration-dependent manner. Gastric cancer specimen with high ROR1 had higher rates of relapse and metastasis than gastric adenocarcinomas expressing low levels of ROR1.Gastric cancer patients with high expression of ROR1 had a short survival time. ROR1 was expressed by gastric cancer cell lines, but not on normal gastric epithelial cell line. Suppressing ROR1 in gastric cancer cell lines impaired their invasion, migration, scratch healing and clone formation ability in vitro and slowed down the tumor growth of MKN-45 cells in immunodeficient mice in vivo. Collectively, our study indicated that dexamethasone up-regulated ROR1 levels on gastric cancer cells. ROR1 participated in and mediated the role of dexamethasone in promoting gastric tumor growth, and blocking ROR1 can prevent the tumor growth.

Assessing the impact of green tax reforms on corporate environmental performance and economic growth: do green reforms promote the environmental performance in heavily polluted enterprises?

Based on Porter's hypothesis and Pollution Shelter's hypothesis, this paper firstly constructs a mechanism of environmental protection tax law and corporate environmental performance. Secondly, it empirically examines the impact of green tax reform on corporate environmental performance and its internal mechanism through the difference in difference (DID) method. The study findings firstly reveal that environmental protection tax law significantly and progressively promotes the improvement of corporate environmental performance. Secondly, the heterogeneity analysis results show that the promotion effect of environmental protection tax law on corporate environmental performance is significant in enterprises with strong financial constraints and stronger internal transparency. The environmental performance improvement effect of the state-owned enterprises is stronger, which indicates that state-owned enterprises can set an example in the face of the formal implementation of the environmental protection tax law. In addition, the heterogeneity of corporate governance shows that the background of senior executives is an important factor affecting the effect of environmental performance improvement. Thirdly, the mechanism analysis indicates that the environmental protection tax law mainly promotes the improvement of enterprise environmental performance by strengthening the local government's enforcement rigidity, improving the local government's environmental concern, promoting enterprise green innovation, and resolving the collusion between government and enterprise. Further analysis shows that the environmental protection tax law based on the empirical results of this paper did not significantly trigger the phenomenon of cross-regional negative pollution transfer of enterprises. The findings of the study have important enlightenment on improving the green governance of enterprises and promoting the high-quality development of national economy.

Genetic and enzymatic characterization of two novel blaNDM-36, -37 variants in Escherichia coli strains.

The widespread of different NDM variants in clinical Enterobacterales isolates poses a serious public health concern, which requires continuous monitoring. In this study, three E. coli strains carrying two novel blaNDM variants of blaNDM-36, -37 were identified from a patient with refractory urinary tract infection (UTI) in China. We conducted antimicrobial susceptibility testing (AST), enzyme kinetics analysis, conjugation experiment, whole-genome sequencing (WGS), and bioinformatics analysis to characterize the blaNDM-36, -37 enzymes and their carrying strains. The blaNDM-36, -37 harboring E. coli isolates belonged to ST227, O9:H10 serotype and exhibited intermediate or resistance to all ß-lactams tested except aztreonam and aztreonam/avibactam. The genes of blaNDM-36, -37 were located on a conjugative IncHI2-type plasmid. NDM-37 differed from NDM-5 by a single amino acid substitution (His261Tyr). NDM-36 differed from NDM-37 by an additional missense mutation (Ala233Val). NDM-36 had increased hydrolytic activity toward ampicillin and cefotaxime relative to NDM-37 and NDM-5, while NDM-37 and NDM-36 had lower catalytic activity toward imipenem but higher activity against meropenem in comparison to NDM-5. This is the first report of co-occurrence of two novel blaNDM variants in E. coli isolated from the same patient. The work provides insights into the enzymatic function and demonstrates the ongoing evolution of NDM enzymes.

Transcriptomics Dissection of Calorie Restriction and Exercise Training in Brown Adipose Tissue and Skeletal Muscle.

Calorie restriction (CR) and exercise training (EX) are two critical lifestyle interventions for the prevention and treatment of metabolic diseases, such as obesity and diabetes. Brown adipose tissue (BAT) and skeletal muscle are two important organs for the generation of heat. Here, we undertook detailed transcriptional profiling of these two thermogenic tissues from mice treated subjected to CR and/or EX. We found transcriptional reprogramming of BAT and skeletal muscle as a result of CR but little from EX. Consistent with this, CR induced alterations in the expression of genes encoding adipokines and myokines in BAT and skeletal muscle, respectively. Deconvolution analysis showed differences in the subpopulations of myogenic cells, mesothelial cells and endogenic cells in BAT and in the subpopulations of satellite cells, immune cells and endothelial cells in skeletal muscle as a result of CR or EX. NicheNet analysis, exploring potential inter-organ communication, indicated that BAT and skeletal muscle could mutually regulate their fatty acid metabolism and thermogenesis through ligands and receptors. These data comprise an extensive resource for the study of thermogenic tissue molecular responses to CR and/or EX in a healthy state.

The spatial distribution and abundance of microplastics in lake waters and ice during ice-free and ice-covered periods.

Understanding the spatial distribution and characteristics of microplastics (MPs) in lake waters is essential to assessing and addressing lacustrine MP pollution. This study investigated how lake ice affects the abundance, spatial distribution, and characteristics (size, shape) of MPs in Lake Ulansuhai by analyzing samples collected at ten sites uniformly distributed throughout the lake during ice-free and ice-covered periods. The abundance of MPs ranged between 204 ± 28 and 1224 ± 185 n·L-1 in lake waters during the ice-free period, and from 34 ± 8 to 216 ± 21 n·L-1 and 269 ± 84 to 915 ± 117 n·L-1 in water and ice during the ice-covered period, respectively. During the ice-covered period, MPs were 2.74-8.14 times higher in the ice than in water beneath the ice. Ice formation decreased MP abundance in lake waters, in part, by incorporating a relatively high percentage of MPs into the ice mass during freezing and by inhibiting atmospheric MPs from reaching the lake waters. The abundance of MPs in the water during the ice-free period was 4.50-11.30 times greater than during the ice-covered period. Seasonal variations in MP shape also occurred; the proportion of fibrous MPs in water decreased during the ice-covered period. Variations in MP abundance were partly due to differences in sedimentation rates; the settling of fibrous MPs is slower, making it easier for them to be captured during the formation of surface ice. Spatially, MPs were uniformly distributed during the ice-free period, but exhibited a spatially distinct pattern during ice-covered periods, when MPs in lake waters were higher in the northeast and lower in the southwest portions of the lake. During the ice-free period, small MPs (0.05-0.5 mm) were more likely to move with currents in the lake, whereas water velocities were reduced by ice formation, allowing small MPs to accumulate near the lake inlet.

TCN1 Deficiency Inhibits the Malignancy of Colorectal Cancer Cells by Regulating the ITGB4 Pathway.

Background/Aims: This study aimed to investigate the biological function and regulatory mechanism of TCN1 in colorectal cancer (CRC). Methods: We studied the biological function of TCN1 by performing gain-of-function and loss-of-function analyses in HCT116 cell lines; examined the effects of TCN1 on the proliferation, apoptosis, and invasion of CRC cells; and determined potential molecular mechanisms using HCT116 and SW480 CRC lines and mouse xenotransplantation models. Tumor xenograft and colonization assays were performed to detect the tumorigenicity and metastatic foci of cells in vivo. Results: TCN1 knockdown attenuated CRC cell proliferation and invasion and promoted cell apoptosis. Overexpression of TCN1 yielded the opposite effects. In addition, TCN1-knockdown HCT116 cells failed to form metastatic foci in the peritoneum after intravenous injection. Molecular mechanism analyses showed that TCN1 interacted with integrin subunit ß4 (ITGB4) to positively regulate the expression of ITGB4. TCN1 knockdown promoted the degradation of ITGB4 and increased the instability of ITGB4 and filamin A. Downregulation of ITGB4 at the protein level resulted in the disassociation of the ITGB4/plectin complex, leading to cytoskeletal damage. Conclusions: TCN1 might play an oncogenic role in CRC by regulating the ITGB4 signaling pathway.

Characterization of nontyphoidal Salmonella strains from a tertiary hospital in China: serotype diversity, multidrug resistance, and genetic insights.

Objective: Nontyphoidal Salmonella is a significant public health concern due to its ability to cause foodborne illnesses worldwide. This study aims to characterize the nontyphoidal Salmonella strains isolated from patients in China. Methods: A total of 19 nontyphoidal Salmonella strains were characterized through serovar identification, antimicrobial susceptibility testing (AST), biofilm formation assessment. Genetic relatedness was determined using pulsed-field gel electrophoresis (PFGE). WGS was employed to decipher the resistance mechanism and to contextualize the S. serovar Mbandaka strains among previously sequenced isolates in China. The biofilm associated mrkA gene was examined by PCR. Results: The predominant serovar identified was S. Enteritidis, followed by S. Mbandaka, S. Thompson, S. Livingston, S. Alachua, and S. Infantis. PFGE analysis indicated a notable genetic similarity among the S. Mbandaka isolates. Phylogenetic analysis suggested that these strains were likely derived from a single source that had persisted in China for over five years. One multidrug resistance (MDR) S. Enteritidis isolate carried a highly transferable IncB/O/K/Z plasmid with bla CTX-M-15. One S. Thompson strain, harboring the mrkABCDF operon in an IncX1 plasmid, isolated from cutaneous lesions, demonstrated robust biofilm formation. However, no mrkABCDF loci were detected in other strains. Conclusion: Our study emphasizes the importance of persisted surveillance and prompt response to Salmonella infections to protect public health. The dissemination of bla CTX-M-15-harboring IncB/O/K/Z plasmid and the spread of virulent mrkABCDF operon among Salmonella in China and other global regions warrant close monitoring.

Application of a microplastic trap to the determination of the factors controlling the lakebed deposition of microplastics.

Microplastics (MPs) in aquatic environments are hard to degrade, easy to transport, and potentially hazardous to biota. Previous studies of MPs in lakes have shown that their deposition is a significant process controlling both their lateral dispersal from a source, and their concentration within the water column. However, the lakebed depositional rates of MPs have predominantly been determined using laboratory experiments and/or through model simulations that may not fully reflect field conditions. In this paper, lacustrine depositional rates in Lake Ulansuhai were documented using an MP trap that allowed for the assessment and quantification of the depositional rates of MPs of differing size, density, and shape at three sampling sites over five different time periods. The results showed that the downward flux for all types of MPs near the lakebed was correlated with wind speed. Higher wind speeds led to the resuspension of greater amounts of MPs in the lakebed sediments and the transport of greater amounts of MPs from the lake inlet to the lake interior and outlet along the hydrologic flow directions. Consequently, higher wind speeds increased the abundance of MPs at the sediment-water interface and intensified the vertical mixing of MPs in the lake water, resulting in a higher depositional flux of MPs. Particles of differing size, shape, and density exhibited different depositional rates. In general, fragmentary, larger size, and higher density MPs were more likely to be deposited. Thus, size and shape have a strong effect on the migration and deposition of HDMPs in Lake Ulansuhai.

Charge Compensation Mechanisms and Oxygen Vacancy Formations in LiNi1/3Co1/3Mn1/3O2: First-Principles Calculations.

Charge compensation mechanisms in the delithiation processes of LiNi1/3Co1/3Mn1/3O2 (NCM111) are compared in detail by the first-principles calculations with GGA and GGA+U methods under different U values reported in the literature. The calculations suggested that different sets of U values lead to different charge compensation mechanisms in the delithiation process. Co3+/Co4+ couples were shown to dominate the redox reaction for 1 ≥ x ≥ 2/3 by using the GGA+U 1 method (U 1 = 6.0 3.4 3.9 for Ni, Co, and Mn, respectively). However, by using the GGA+U 2 (U 2 = 6.0 5.5 4.2) method, the results indicated that the redox reaction of Ni2+/Ni3+ took place in the range of 1 ≥ x ≥ 2/3. Therefore, according to our study, experimental charge compensation processes during delithiation are of great importance to evaluate the theoretical calculations. The results also indicated that all the GGA+U i (i = 1, 2, 3) schemes predicted better voltage platforms than the GGA method. The oxygen anionic redox reactions during delithiation are also compared with GGA+U calculations under different U values. The electronic density of states and magnetic moments of transition metals have been employed to illustrate the redox reactions during the lithium extractions in NCM111. We have also investigated the formation energies of an oxygen vacancy in NCM111 under different values of U, which is important in understanding the possible occurrence of oxygen release. The formation energy of an O vacancy is essentially dependent on the experimental conditions. As expected, the decreased temperature and increased oxygen partial pressure can suppress the formation of the oxygen vacancy. The calculations can help improve the stability of the lattice oxygen.

[Characteristics of Bacterial Community Structure in Wuliangsu Lake During an Irrigation Interval in Hetao Plain].

In order to study the bacterial community composition and corresponding function in Wuliangsu Lake at the end of the Hetao Plain during the irrigation gap period, lake samples were collected in September 2020, and the pH, TN, TP, DIP, DTP, NH4+-N, Chla, EC, SAL, and other indicators were analyzed. The 16S rRNA high-throughput sequencing method was used to explore the attached bacteria and bacterioplankton in 15 samples of the surface water in Wuliangsu Lake. The experimental results showed that:① the alpha diversity Chao and Shannon indices of attached bacteria were greater than that of bacterioplankton, but the median of Shannoneven index was the same. ② In each sampling point, the bacterioplankton of Proteobacteria and Actinobacteria in the top five dominant bacteria phyla were higher than that of attached bacteria, and the abundance of attached bacteria and bacterioplankton of Bacteroidota were staggered. On the contrary, the contents of attached bacteria of Verrucomicrobiota and Cyanobacteria were all higher than that of bacterioplankton. ③ Redundant analysis showed that pH had the most significant effect on dominant attached bacteria, and the effect of conductivity and salinity in dominant bacterioplankton was the most significant. ④ PICRUSt2 function prediction analysis showed that attached bacteria and planktonic bacteria had the strongest metabolic functions, showing abundant metabolic functions. There were 29 nitrogen-related effective KOs and 88 phosphorus-related effective KOs, with the greatest nitrogen-fixing function and strong inorganic phosphorus-dissolving function, and bacterioplankton played a greater role in the two functions.

[Deposition Law of Low-Density Microplastics Aggregation in Wuliangsu Lake].

Deposition is the main migration process of low-density microplastic aggregation in lakes. In order to explore the deposition law of low-density microplastic aggregation in Wuliangsu Lake, a microplastic trap was designed and applied to examine the deposition process based on the similarities and differences between microplastics and naturally occurring suspended solids. The deposition processes of different sizes and shapes of low-density microplastic aggregation were quantified in Wuliangsu Lake. The results showed that the deposition fluxes of all types of low-density microplastic aggregation increased with wind speed. The deposition of flux of low-density microplastic aggregations with a similar shape of fiber and with a size ranging from 0.05-0.5, 0.5-2, and 2-5 mm had better correlation with wind speed. The correlation coefficient changed from 0.218 to 0.836. The deposition of flux of low-density microplastic aggregations with a similar shape of fiber, fragment, grain, and film and with size ranging from 0.05-0.5, 0.5-2, and 2-5 mm under different wind speeds at different experiment sites changed from 0-(1458±284), 0-(368±144), 0-(71±37), and 0-(85±65)n·(m2·d)-1, respectively. Furthermore, we found that, when shape was held constant, larger low-density microplastic aggregations were more likely to be deposited, whereas smaller low-density microplastic aggregations were more likely to be transported. When size was held constant, fragmentary low-density microplastic aggregations were more likely to be deposited than fibrous and film microplastic.