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Microbial corrosion is the deterioration of materials associated with microorganisms in environments, especially in oil- and gas-dominated sectors. It has been widely reported to cause great losses to industrial facilities such as drainage systems, sewage structures, food-processing equipment, and oil and gas facilities. Generally, bacteria, viruses, and other microorganisms are the most important microorganisms associated with microbial corrosion. The destructive nature of these microorganisms differs based on the kind of bacteria involved in the corrosion mechanism. Amongst the microorganisms related to microbial corrosion, sulfate-reducing bacteria (SRB) is reported to be the most common harmful bacteria. The detailed mechanistic explanations relating to the corrosion of pipelines by sulfate-reducing bacteria are discussed. The mechanism of microbial corrosion in pipelines showing the formation of pitting corrosion and cathodic depolarization is also reported. The current review provides theoretical information for the control and protection of pipelines caused by microbial corrosion and how new eco-friendly protection methods could be explored. [ABSTRACT FROM AUTHOR]

Although more scholars have studied the economic consequences of ESG, no conclusive results have been reached yet. In addition, there is a lack of research on the relationship between corporate ESG performance and surplus persistence. This paper adopts the ordinary least squares (OLS) method to analyze the impact of corporate ESG performance on corporate surplus persistence based on stakeholder theory and principal-agent theory using companies listed in Shanghai and Shenzhen A-shares from 2010 to 2022 as research objects. It was found that there is a significant positive correlation between ESG performance and both the social (S) and governance (G) dimensions, as well as surplus sustainability; conversely, the environmental (E) dimension is significantly negatively correlated with surplus sustainability in the short term, but further analysis reveals that it can enhance corporate surplus sustainability in the long run. Institutional investor shareholding and debt financing costs mediate the relationship between corporate ESG performance and both the S and G dimensions, influencing surplus persistence. Further analysis shows that the positive correlation between a firm's ESG performance and its governance (G) dimension related to surplus persistence is more significant in the eastern region. [ABSTRACT FROM AUTHOR]

Inter-basin water transfer projects, such as the Yellow River to Qingdao Water Diversion Project (YQWD), are essential for addressing water scarcity, but impact local aquatic ecosystems. This study investigates the seasonal characteristics of eukaryotic microbial communities in the Jihongtan Reservoir, the main water-receiving body of YQWD, over a one-year period using 18S rDNA amplicon sequencing. The results showed that the eukaryotic microbial diversity did not exhibit significant seasonal variation (p > 0.05), but there was a notable variance in the community structure (p < 0.05). Arthropoda and Paracyclopina, representing the most dominant phylum and the most dominant genus, respectively, both exhibited the lowest abundance during the winter. The Chlorophyta, as the second-dominant phylum, demonstrates its higher abundance in the spring and winter. The Mantel test and PLS-PM (Partial Least Squares Path Modeling) revealed that water temperature (WT), dissolved oxygen (DO), and pH influenced the seasonal dynamic of eukaryotic microbial communities significantly, of which WT was the primary driving factor. In addition to environmental factors, water diversion is likely to be an important influencing factor. The results of the co-occurrence network and robustness suggested that the spring network is the most complex and exhibits the highest stability. Moreover, keystone taxa within networks have been identified, revealing that these key groups encompass both abundant and rare species, with specificity to different seasons. These insights are vital for understanding the seasonal variation of microbial communities in the Jihongtan Reservoir during ongoing water diversions. [ABSTRACT FROM AUTHOR]

Using the sample of Chinese A-share listed firms from 2010 to 2020, this study examines the impact of non-controlling large shareholders (NCLSs) on corporate capital structure adjustment. The results show that NCLSs significantly increase the dynamic capital structure adjustment speed and reduce capital structure deviation. NCLSs have an asymmetric influence on capital structure adjustment speed for different deviation directions, i.e. compared to the speed of upward adjustment after a downward deviation of the capital structure, the effect of NCLSs on the speed of downward adjustment of the capital structure after an upward deviation is stronger. Whether in state-owned enterprises (SOEs) or non-state-owned enterprises (NSOEs), NCLSs significantly increase the dynamic capital structure adjustment speed. However, compared with SOEs, NCLSs in NSOEs have a more significant positive impact on the dynamic capital structure adjustment speed. The mechanism analysis suggests that reducing agency costs and mitigating financing constraints serve as the important channels through which NCLSs influence the dynamic adjustment of capital structure. This paper not only enriches and improves the theoretical basis of dynamic capital structure adjustment, but also helps to deepen the understanding of dynamic capital structure adjustment of Chinese listed firms. [ABSTRACT FROM AUTHOR]

Effects of potassium monopersulfate (KMPS) on the nitrification activity, aquacultural water quality and bacterial community structure of sponge biocarriers with pre-cultured biofilm (SBBF) were analysed through shaking flask experiments and L. vannamei aquaculture experiments. Changes in the ammonia oxidation rate (AOR) and nitrite oxidation rate (NOR) of SBBF under six KMPS concentration treatments (0, 1, 2, 3, 4 and 5 mg/L) were studied. The results showed that the AOR and NOR of SBBF treated with high concentrations of KMPS (3, 4 and 5 mg/L) were significantly lower than those of the control group (CK) (p < 0.05). However, compared with the first dosing of NH4Cl and NaNO2, the inhibition of AOR and NOR by KMPS on AOR and NOR was weakened after the second and third dosing times. That is, AOR and NOR can recover partially or completely over time. The L. vannamei aquaculture experiment was performed using four concentrations of KMPS (0, 2, 4 and 8 mg/L). The results showed that with increasing KMPS dosage, the average and peak concentrations of NH4+-N and NO2–-N in each treatment significantly increased (P < 0.05), and the final body weight of shrimp significantly decreased (P < 0.05). Furthermore the highest dose (8.0 mg/L) of KMPS reduced the survival rate by 9.33% compared to the CK. High-throughput sequencing analysis of the biofilm structure showed that the relative abundances of Nitrospirota, Nitrosomonas and Nitrococcus, which are related to nitrogen cycling, and beneficial bacteria including Firmicutes and Bacilli decreased with the addition of KMPS (p < 0.05). [ABSTRACT FROM AUTHOR]

Social technologies have enabled the emergence of online platforms that provide offline service consultations and recommendations. In this environment, economic inefficiency arises when customers are not fully aware of their horizontally differentiated preferences. With its expertise or data dominance, a platform can be more informed about customers' hidden preferences. We focus on an instrumental social technology, that is, targeting, which is a type of data-driven personalized information provision to manipulate customers' beliefs about service quality. We propose a Hotelling model wherein customers are sensitive to the delays for service while making Bayesian belief updates based on a platform's recommendations. When customers self-select their favorite service, their choices impose negative externalities through congestion and welfare loss. Our results indicate that service recommendations allow customers to navigate toward the more appropriate service, thus improving matching efficiency, reducing congestion costs, and enhancing aggregate customer welfare. We further identify the role of "information transparency" and study how the platform should strategically release information by making personalized service recommendations to customers. Interestingly, when a customer-centric platform maximizes aggregate customer welfare, we identify the "value of opaqueness" by strategically withholding service recommendations from a subset of customers and notice that this effect is more pronounced for a profit-seeking platform. Our results offer a better understanding of information transparency policies in the joint design of service recommendation systems and pricing mechanisms. [ABSTRACT FROM AUTHOR]

Chlorella pyrenoidosa is a widely used microalgae in the aquaculture process of Litopenaeus vannamei. In order to evaluate the effects of supplementing C. pyrenoidosa on water quality, shrimp growth performance, and biofilm bacterial community structure in L. vannamei aquaculture systems, C. pyrenoidosa suspension was supplemented in the precultured biofilm (PB) and water exchange (WE) culture systems. The results showed that supplementation with C. pyrenoidosa significantly increased the turbidity and the concentrations of total ammonia nitrogen (TAN) and nitrite nitrogen (NO 2 − ─N) in the PBC system (the PB system supplemented with C. pyrenoidosa), but had no significant effect on those in the WEC system (the WE system supplemented with C. pyrenoidosa). However, the TAN concentration of all systems remained at a low level (<0.1 mg/L) throughout the experiment. Additionally, supplementation with C. pyrenoidosa decreased the final concentrations of total phosphorus in the PBC and WEC systems by 15.74% and 23.33%, respectively. With the supplementation of C. pyrenoidosa, the final weight, final biomass, and average daily growth rate of L. vannamei increased, while the feed conversion ratio decreased. 16srRNA high-throughput sequencing results showed that the supplementation of C. pyrenoidosa to the PBC system resulted in a decrease in the relative abundances of Proteobacteria and Bacteroidetes and an increase in the relative abundance of Acidobacteria. Compared to those in the initial biofilm sample, the relative abundances of nitrifying bacteria, Nitrosococcus, Nitrosomonas, Nitrococcus, and Nitrospira, in PBCF (biofilm in the PB systems with C. pyrenoidosa) and PBOF (biofilm in the PB systems without C. pyrenoidosa) decreased from 10.18% to 3.05% and 0.75%, respectively. In conclusion, C. pyrenoidosa, as a supplement to the aquaculture systems, has practical application prospects. [ABSTRACT FROM AUTHOR]

Bartonella grahamii is one of the most prevalent Bartonella species in wild rodents and has been associated with human cases of neuroretinitis. The structure and distribution of genomic diversity in natural B. grahamii is largely unexplored. Here, we have applied a comprehensive population genomic and phylogenomic analysis to 172 strains of B. grahamii to unravel the genetic differences and influencing factors that shape its populations. The findings reveal a remarkable genomic diversity within the species, primarily in the form of single- nucleotide polymorphisms. The open pangenome of B. grahamii indicates a dynamic genomic evolution influenced by its ecological niche. Whole-genome data allowed us to decompose B. grahamii diversity into six phylogroups, each characterized by a unique "mosaic pattern" of hosts and biogeographic regions. This suggests a complex interplay between host specificity and biogeography. In addition, our study suggests a possible origin of European strains from Asian lineages, and host factors have a more significant impact on the genetic differentiation of B. grahamii than geographical factors. These insights contribute to understanding the evolutionary history of this pathogen and provide a foundation for future epidemiological research and public health strategies., Importance: Bartonella grahamii has been reported worldwide and shown to infect humans. Up to now, an effective transmission route of B. grahamii to humans has not been confirmed. The genetic evolution of B. grahamii and the relationship between B. grahamii and its host need to be further studied. The factors driving the genetic diversity of B. grahamii are still controversial. The results showed that the European isolates shared a common ancestor with the Chinese isolates. Host factors were shown to play an important role in driving the genetic diversity of B. grahamii . When host factors were fixed, geographic barriers drove B. grahamii microevolution. Our study emphasizes the importance of characterizing isolate genomes derived from hosts and geographical locations and provides a new reference for the origin of B. grahamii ., Competing Interests: The authors declare no conflict of interest.

In this study, we investigated the prevalence of Bartonella in deer from Qilian County, Qinghai Province, China. Blood samples were collected from 69 red deer, 40 white-lipped deer, and 27 sika deer. The detection of Bartonella spp. has been conducted. The overall prevalence of Bartonella was 33.6% (46/135). Species-specific prevalence was 50.72% in red deer (35/69), 20.00% in white-lipped deer (8/40), and 11.11% in sika deer (3/27). There were significant differences in the prevalence rates among the different species of deer. The amplicon sequence comparison revealed a high homology of the ruminant-associated Bartonella spp. Nanopore sequencing further confirmed the results. Bartonella reads were presented in each of the qPCR-positive samples. Phylogenetic analysis indicated that the Bartonella sequences detected in deer blood were closely related to ruminant-borne Bartonella spp. In summary, we reported the Bartonella prevalence of different deer species in Qinghai, and there were at least one species of ruminant-associated Bartonella , B. schoenbuchensis ., Importance: This is the first report about Bartonella infections in the deer population from China. We found that there were two species of Bartonella and an unidentified species of Bartonella among the unculturing strains carried by these deer populations. We first used Nanopore sequencing to detect Bartonella from deer blood samples and indicated that Nanopore sequencing is beneficial to detect pathogens due to its advantage of real-time and high sensitivity., Competing Interests: The authors declare no conflict of interest.

Fusarium root rot is usually classified as an extremely destructive soilborne disease. From 2020 to 2021, Fusarium root rot was observed in production areas and seriously affected the yield and quality of Scutellaria baicalensis in Shanxi Province, China. Based on morphological characteristics and combined analysis of the internal transcribed spacer region of ribosomal DNA and translation elongation factor 1-alpha sequences, 68 Fusarium isolates obtained in this work were identified as F. oxysporum (52.94%), F. acuminatum (20.59%), F. solani (16.17%), F. proliferatum (5.88%), F. incarnatum (2.94%), and F. brachygibbosum (1.47%). In the pathogenicity tests, all Fusarium isolates could infect S. baicalensis roots, presenting different pathogenic ability. Among these isolates, F. oxysporum was found to have the highest virulence on S. baicalensis roots, followed by F. acuminatum, F. solani, F. proliferatum, F. brachygibbosum , and F. incarnatum . According to fungicide sensitivity tests, Fusarium isolates were more sensitive to fludioxonil and difenoconazole, followed by carbendazim, thiophanate-methyl, and hymexazol. In brief, this is the first report of Fusarium species ( F. oxysporum, F. acuminatum, F. solani, F. proliferatum, F. incarnatum , and F. brachygibbosum ) as causal agents of root rot of S. baicalensis in Shanxi Province, China. The fungicide sensitivity results will be helpful for formulating management strategies of S. baicalensis root rot., Competing Interests: The author(s) declare no conflict of interest.

Introduction: Massilia bacteria are widely distributed and have various ecological functions. Preliminary studies have shown that Massilia is the dominant species in constructed wetland ecosystems, but its species composition and distribution in constructed wetlands are still unclear., Methods: In this paper, the in-house-designed primers were used to construct a 16S rDNA clone library of Massilia . The RFLP sequence analysis method was used to analyze the diversity of Massilia clone library and the composition of Massilia in sewage, substrate, plant rhizosphere, plant phyllosphere and air in a constructed wetland sewage treatment system. Redundancy analysis (RDA) and canonical correspondence analysis (CCA) were used to analyze the correlation between environmental factors and the population characteristics of Massilia in the corresponding environment. The dominant species of Massilia were analyzed for differences., Results: The results showed that the 16S rDNA clone library in primer 5 worked well. According to the clone library diversity index analysis, the richness of Massilia varied significantly in different environments in different seasons, where the overall summer and autumn richness was higher than that in the spring and winter. The relative abundance of 5 Massilia in the constructed wetland ecosystem was greater than 1% in all samples, which were M. alkalitolerans , M. albidiflava , M. aurea , M. brevitalea , and M. timonae . The seasonal variation of dominant genera was significantly correlated with environmental factors in constructed wetlands., Discussion: The above results indicated that the species of Massilia were abundant and widely distributed in the constructed wetland ecosystem, and there were significant seasonal differences. In addition, the Massilia clone library of constructed wetland was constructed for the first time in this study and the valuable data of Massilia community structure were provided, which was conducive to the further study of microbial community in constructed wetland., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Xu, Liu, Zhao, Song and Sun.)

Objective: To evaluate the role of the Simple Rules (SR) from the International Ovarian Tumor Analysis group in contrast-enhanced ultrasound (CEUS) of for the differential diagnosis of benign and malignant adnexal tumors., Methods: A total of 180 patients with suspected malignant adnexal masses admitted to Lanzhou University Second Hospital were included, all of whom received conventional ultrasound (US) and CEUS examination before surgery. All masses were assessed using SR in US and SR in CEUS. To compare the diagnostic performance, the sensitivity, specificity, negative and positive predictive values, Youden index, and area under the curves values of SR in US and SR in CEUS were obtained., Results: Sensitivity, negative predictive values, Youden index, and area under the curves were better for SR in CEUS than SR in US. The specificity and negative predictive value of SR in CEUS were lower than that of SR in US. Compared with SR in US, SR in CEUS significantly reduced the number of uncertain masses (21, 36.7% vs. 66, 11.7%)., Conclusion: We concluded that SR in CEUS performed well in the diagnosis of malignant adnexal masses. SR in CEUS is a supplement to SR in US., (© 2021 International Federation of Gynecology and Obstetrics.)