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β-cyclodextrin (β-CD) is an important cyclic oligosaccharide, which is widely applicated in foods, environmental protection, and cosmetics, primarily prepared from enzymatic synthesis in traditional industry. However, several challenges persist, including cumbersome processes and difficulties in achieving continuous fermentation and catalysis. This research introduced a biofilm-based immobilized fermentation, integrating with enzyme catalysis system of surface display in Bacillus subtilis. The bslA gene was selected to construct the surface display system due to its ability to promote biofilm formation and serve as an anchorin. Compared to free cell catalysis, the biofilm-based immobilized catalysis expanded the temperature range to 40–70 and the pH range to 5–7.5. During the continuous catalysis process, by the 13th batch, the relative activity remained around 52%, and the conversion rate exceeded 36%, similar to the single-batch free cell catalysis. These findings provide valuable insights and effective strategies for the industrial production of β-CD and other biochemicals through continuous catalysis. [ABSTRACT FROM AUTHOR]

Regulation of steroid hormone receptors (SHRs) on transcriptional reprogramming is crucial for breast cancer progression. SHRs, including estrogen receptor (ER), androgen receptor (AR), progesterone receptor (PR), and glucocorticoid receptor (GR) play key roles in remodeling the transcriptome of breast cancer cells. However, the molecular mechanisms by which SHRs regulate chromatin landscape in enhancer regions and transcription factor interactions remain largely unknown. In this review, we summarized the regulatory effects of 3 types of SHRs (AR, PR, and GR) on gene transcription through chromatin interactions and enhancer reprogramming. Specifically, AR and PR exhibit bi-directional regulatory effects (both inhibitory and promoting) on ER-mediated gene transcription, while GR modulates the transcription of pro-proliferation genes in ER-positive breast cancer cells. In addition, we have presented four enhancer reprogramming mechanisms (transcription factor cooperation, pioneer factor binding, dynamic assisted loading, and tethering) and the multiple enhancer-promoter contact models. Based on these mechanisms and models, this review proposes that the combination of multiple therapy strategies such as agonists/antagonists of SHRs plus endocrine therapy and the adoption of the latest sequencing technologies are expected to improve the efficacy of ER positive breast cancer treatment. [ABSTRACT FROM AUTHOR]

Over the past few decades, polymers with dynamic covalent bonds have received a lot of attention due to their self‐healing, shape memory, and environmental adaptation properties. However, most of them require a change in catalyst or environmental conditions to achieve bond reduction and exchange reactions, and the harsh conditions are not conducive to the practical application of the material. However, the dr‐polyurea based polyurethane (PUU) can be prepared at low temperatures, and can be worn and rebuilt in a catalyst free and mild environment, thus showing excellent self‐healing function. In this paper, the unique dynamic reaction mechanism of hindered urea bond (HUB), the properties of related polymers and the development of frontier are reviewed. In addition, the performance research of HUB and the application prospect of innovative synthetic PUU are also reviewed. [ABSTRACT FROM AUTHOR]

The brake system is a key component of a high-speed train, which suffers intense wheel-rail interactions caused by wheel polygonal wear (WPW) in realistic working conditions. To explore the dynamic characteristics of the disc brake systems with WPW, a rigid-flexible coupled vehicle dynamics model is proposed. The developed model systematically takes into account the flexible deformation of brake components and wheelsets, measured WPW and non-linear factors such as wheel-rail interaction, disc-pad friction and non-linear damping characteristics. It allows the dynamic behaviors of the vehicle brake system in service to be accurately and effectively revealed. The model is verified using line test data, and then the dynamic characteristics of disc brake systems with WPW are investigated in details. The results show that for vehicle speed below 80 km/h and depths of WPW below 0.04 mm, the effect of WPW on the vibration of the caliper is slight. However, as vehicle speed and wear depth continue to rise, the vibration of the caliper increases noticeably. Furthermore, the effects of vehicle speed and wear depth on brake disc vibration are more obvious, and increasing vehicle speed and wear depth will steadily deteriorate the vibration of the disc. Besides, the effect of WPW is particularly pronounced on the dynamic behavior of the brake units closer to the wheels. Overall, the influence of wheel polygon cannot be neglected in the study of dynamic characteristics of brake system. At the same time, the proposed model can also be applied in the strength evaluation of brake components and the study of the tribological behaviors within the brake interface. [ABSTRACT FROM AUTHOR]

Mine gas accidents have received widespread attention at home and abroad, because mine gas accidents often cause casualties and property losses once they occur. This study was conducted in order to have a more comprehensive understanding of the research status of and research hotspots in coal mine gas management at home and abroad, and to provide references for relevant researchers' studies and literature searches. Using the Web of Science (WOS) core database as the data source, this paper analyzed the data from the period of 2000–2023 under the headings of "gas governance", "Gas Control Technology", "Pre-mining gas methods in coal mines", "Methods of Gas Mining in Coal Mines", "Post-mining gas", and "Post-mining gas methods in coal mines". "Methods in Coal Mines", "Methods of Gas Mining in Coal Mines", and "Post-mining Gas Methods in Coal Mines" were searched, and the CiteSpace tool was utilized to provide a multi-dimensional visual presentation of the literature, including authors, the number of journals issued, countries of issue, keywords, etc., in order to explore the research hotspots in this field. The analysis results show the following: the development process in the field of gas prevention and control is mainly divided into the three stages of initial exploration, steady development, and explosive surge; China, Australia, and the United States are the top three countries in terms of the number of articles published, and they have a greater influence in the field, but there is a closer connection between the regions in Europe; a certain group size has been formed by the researchers and research institutes in this field, the China University of Mining and Technology is more active in this field, ranking as the first in terms of the number of articles issued, and it has a cooperative relationship with many universities; Kai Wang and Enyuan Wang are the core authors in this field, while C. Ozgen Karacan also has a large body of research in the field, and his research results are widely recognized; the main journals issued in this field are Fuel and Energy Policy, while other journals have been frequently cited, and these journals have an important role in the field. In these journals, "Coal mine methane: A review of capture and utilization practices with benefits to mining safety and to greenhouse gas reduction" is one of the most important articles in the field. Thin coal seams, coal mining workings, and coal and gas protrusion are current research hotspots. [ABSTRACT FROM AUTHOR]

[Objective] To reveal the spatial and temporal evolution characteristics of soil water erosion in the middle reaches of the Yellow River in the rich and coarse sediment area from 2000 to 2020, and analyze its dynamic driving force. [Methods] Based on the RUSLE model, the annual soil water erosion modulus in the rich and coarse sediment area was calculated, and the variation characteristics of soil water erosion intensity in 2000, 2005, 2010, 2015, and 2020 were analyzed. The spatial-temporal characteristics of soil water erosion modulus were explored by using the Sen + MK trend analysis method combined with the Hurst index, and the factor probing in the parameter-optimal geographical detector with the interactive probing were used to quantify the explanatory power of six factors, namely average annual precipitation, elevation, slope, vegetation cover, land use/cover type, and soil type, on the spatial distribution of soil water erosion. [Results] (1) The area of moderate, intense, extremely intense and severe erosion in the rich and coarse sediment area decreased by 48.09%, 77.93%, 83.01%, and 36.13%, respectively, and the area of slight and mild erosion increased by 46.22% and 0.33%, respectively, in the five periods from 2000 to 2020. At the present stage, the sandy and coarse sandy area was dominated by slight and mild erosion, and the proportion of the two was 62.49% and 42.07% respectively. (2) The overall inter-annual change of soil water erosion modulus in the rich and coarse sediment area showed a fluctuating and significant downward trend, from 2 214.89 t/(km² * a) in 2000 to 1 169.44 t/(km² * a) in 2020. The spatial variation trend of soil water erosion modulus in the rich and coarse sediment area from 2000 to 2020 was mainly in a decreasing state, accounting for 76.13% of the total area, and would continue to be in a decreasing state in the future, with an area share of 62.50%. (3) The explanatory power of the interactions among the six factors was greater than that of ingle factor, and it was mainly manifested as nonlinear enhancement and double-factor enhancement; soil water erosion in the rich and coarse sediment area was dominated by precipitation and land use/cover in 2000-2005, and by vegetation cover and land use/cover in 2010-2020. [Conclusion] Soil water erosion condition in the rich and coarse sediment area will be improved continuously from 2000 to 2020; in the future, the soil water erosion modulus of 62.50% of the regions will continue to decline or decline in the future, but there is still a potential risk of increase in 20.44% of the area; the land use/cover pattern has hanged by the project of returning farmland to forests and grassland, which made the soil water erosion in he rich and coarse sediment area. The driving force of soil water erosion in the rich and coarse sediment area changes dynamically; the slope factor needs to be fully considered when optimizing the land use/cover pattern or the prevention and control of soil water erosion in the rich and coarse sediment area in the future. [ABSTRACT FROM AUTHOR]

Introduction: The purpose of this study is to describe sedation and analgesia management, and identify the factors associated with increased demand for medication in acute respiratory distress syndrome (ARDS) patients receiving venovenous extracorporeal membrane oxygenation (VV-ECMO). Methods: This retrospective, single-center study included consecutive adult ARDS patients who received VV-ECMO for at least 24 hours from January 2018 to December 2020 in a comprehensive intensive care unit. The electronic medical records were retrospectively reviewed to collect data. Results: Forty-two adult patients meeting the inclusion criteria were included in the study. Midazolam, sufentanil, and remifentanil were main sedatives and analgesics used in the patient population. The morphine equivalents, representative of the demand for opioids, was 512.9 (IQR, 294.5, 798.2) mg/day. The midazolam equivalents, representative of benzodiazepine requirement, was 279.6 (IQR, 208.8, 384.5) mg/day. The levels of serum creatinine, total bilirubin, lactic acid, SOFA score, and APACHE Ⅱ score at cannulation were found to be associated with opiate or benzodiazepine requirements. Multiple linear regression analysis revealed a linear correlation between midazolam equivalents and morphine equivalents (p < 0.001). In addition, there was a negative linear correlation between Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ) score and midazolam equivalents (p = 0.024). Conclusions: The sedation and analgesia requirements of ARDS patients receiving VV-ECMO often increase simultaneously. More large-scale studies are needed to confirm the risk factors for increased sedation and analgesia needs in patients supported on VV-ECMO. [ABSTRACT FROM AUTHOR]

Biofilm-immobilized fermentation is a novel strategy that has been utilized in L-lysine fermentation. In this study, we describe a strategy for designing bioreactors for immobilized fermentation. We have constructed steel structures in which the carriers can be sewn, forming several star-like structures with different angles, and changing the ventilation robot to the aeration tray. In a 10-L bioreactor, this structure with 12 angles assisted the immobilized system to remedy the gap between free-cell and immobilized fermentation in the conversion rate. In a 50-L bioreactor, this enlarged structure with 16 angles illustrated a 4.61% higher conversion rate than the free-cell fermentation (67.75%) and increased the production by 28.56%. This successful case is the first step towards to industrial production of biofilm-based immobilized fermentation. Key points • The designed steel structure is useful for L-lysine immobilized fermentation in a 10-L bioreactor. • The conversion rate of immobilized fermentation increased from 13.99 to 60.07% and is 1.03% higher than that of the free-cell fermentation. • The conversion rate of the redesigned 50-L bioreactor is higher than that of free-cell fermentation. [ABSTRACT FROM AUTHOR]

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The accumulation of acetate in Escherichia coli inhibits cell growth and desired protein synthesis, and cell density and protein expression are increased by reduction of acetate excretion. Dissolved oxygen (DO) is an important parameter for acetate synthesis, and the accumulation of acetate is inversely correlated to DO level. In this study, the effect of DO levels on glutamate dehydrogenase (GDH) expression was investigated, and then different DO control strategies were tested for effects on GDH expression. DO control strategy IV (50% 0–9 h, 30% 9–18 h) provided the highest cell density (15.43 g/L) and GDH concentration (3.42 g/L), values 1.59- and 1.99-times higher than those achieved at 10% DO. The accumulation of acetate was 2.24 g/L with DO control strategy IV, a decrease of 40.74% relative to that achieved for growth at 10% DO. Additionally, under DO control strategy IV, there was lower expression of PoxB, a key enzyme for acetate synthesis, at both the transcriptional and translational level. At the same time, higher transcription and protein expression levels were observed for a glyoxylate shunt gene (aceA), an acetate uptake gene (acs), gluconeogensis and anaplerotic pathways genes (pckA, ppsA, ppc, and sfcA), and a TCA cycle gene (gltA). The flux of acetate with DO strategy IV was 8.4%, a decrease of 62.33% compared with the flux at 10% DO. This decrease represents both lower flux for acetate synthesis and increased flux of reused acetate. [ABSTRACT FROM AUTHOR]

Phage infection is common during the production of L‐threonine by E. coli, and low L‐threonine production and glucose conversion percentage are bottlenecks for the efficient commercial production of L‐threonine. In this study, 20 antiphage mutants producing high concentration of L‐threonine were obtained by atmospheric and room temperature plasma (ARTP) mutagenesis, and an antiphage E. coli variant was characterized that exhibited the highest production of L‐threonine Escherichia coli ([E. coli] TRFC‐AP). The elimination of fhuA expression in E. coli TRFC‐AP was responsible for phage resistance. The biomass and cell growth of E. coli TRFC‐AP showed no significant differences from those of the parent strain (E. coli TRFC), and the production of L‐threonine (159.3 g L−1) and glucose conversion percentage (51.4%) were increased by 10.9% and 9.1%, respectively, compared with those of E. coli TRFC. During threonine production (culture time of 20 h), E. coli TRFC‐AP exhibited higher activities of key enzymes for glucose utilization (hexokinase, glucose phosphate dehydrogenase, phosphofructokinase, phosphoenolpyruvate carboxylase, and PYK) and threonine synthesis (glutamate synthase, aspartokinase, homoserine dehydrogenase, homoserine kinase and threonine synthase) compared to those of E. coli TRFC. The analysis of metabolic flux distribution indicated that the flux of threonine with E. coli TRFC‐AP reached 69.8%, an increase of 16.0% compared with that of E. coli TRFC. Overall, higher L‐threonine production and glucose conversion percentage were obtained with E. coli TRFC‐AP due to increased activities of key enzymes and improved carbon flux for threonine synthesis. [ABSTRACT FROM AUTHOR]

In this study, process engineering and process control were applied to increase the production of l‐tryptophan using Escherichia coli Dmtr/pta‐Y. Different dissolved oxygen (DO) and pH control strategies were applied in l‐tryptophan production. DO and pH were maintained at [20% (0–20 hr); 30% (20–40 hr)] and [7.0 (0–20 hr), 6.5 (20–40 hr)], respectively, which increased l‐tryptophan production, glucose conversion percentage [g (l‐tryptophan)/g (glucose)], and transcription levels of key genes for tryptophan biosynthesis and tryptophan biosynthesis flux, and decreased the accumulation of acetate and transcription levels of genes related to acetate synthesis and acetate synthesis flux. Using E. coli Dmtr/pta‐Y with optimized DO [20% (0–20 hr); 30% (20–40 hr)] and pH [7.0 (0–20 hr), 6.5 (20–40 hr)] values, the highest l‐tryptophan production (52.57 g/L) and glucose conversion percentage (20.15%) were obtained. The l‐tryptophan production was increased by 26.58%, the glucose conversion percentage was increased by 22.64%, and the flux of tryptophan biosynthesis was increased to 21.5% compared with different conditions for DO [50% (0–20 hr), 20% (20–40 hr)] and pH [7.0]. [ABSTRACT FROM AUTHOR]

While many extant studies focus on the relation between financial performance and corporate social responsibility (CSR) reporting, less attention has been given to the shifting role of financial performance in CSR reporting in a changing institutional environment. The objective of this study is to investigate whether, why, and how institutional transitions affect the role of financial performance in CSR reporting. Using samples of A‐share listed companies from 2008 to 2015, we separately examine the impacts of institutional transitions on firms' propensity to issue standalone CSR reports, the quality of voluntary CSR reports, and the quality of mandatory CSR reports. We find that financial performance buffers against external pressures brought by institutional transitions rather than only serving as a slack resource. By highlighting the buffer role of financial performance, our study provides deeper insights on the relation between financial performance and CSR reporting and contributes to extant institutional research on CSR reporting. [ABSTRACT FROM AUTHOR]

Purpose The purpose of the paper is to examine the impact of investor sentiment on managers’ decisions to provide CSR disclosures. The core issue focuses on whether, why and how managers adjust their approach to CSR disclosure to cater to the investor sentiment.Design/methodology/approach On the basis of 13,488 observations of A-share listed companies, the authors examine the impacts of investor sentiment on CSR disclosure, which is measured separately by the propensity to issue a standalone CSR report and the quality of CSR reports. Furthermore, the authors examine the moderating role of institutional factors in China.Findings The authors find that during low-sentiment periods, managers are more likely to issue a standalone CSR report and the quality of CSR reports is higher, and vice versa. Additionally, the authors find that the negative correlations between CSR disclosure and investor sentiment are stronger in state-owned enterprises.Research limitations/implications First, the measurement of investor sentiment reflects only a part of characteristics of investor sentiment. Second, the authors pay less attention to the specific items of a CSR report.Originality/value The study contributes to the literature on CSR disclosure and investor sentiment by combining the two fields together. Furthermore, the study deepens the understanding of the institutional context in China and contributes to research on the predictors of CSR disclosure. [ABSTRACT FROM AUTHOR]

Gang Meng SP 1,3 sp -Wei Zhao SP 2 sp -Qingguo Liu SP 2 sp -Chunguang Zhao SP 3 sp - Yannan Zou SP 2 sp -Nan Zhao SP 2 sp -Dong Liu SP 1 sp -Hanjie Ying SP 1 sp -Wenjun Sun SP 1 sp -Yong Chen SP 1 sp SP 1 sp College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China SP 2 sp Nanjing Hi-Tech Biological Technology Research Institute Co. Ltd, Nanjing, China SP 3 sp Ningxia Yipin Biotechnology Co. Ltd, Yinchuan, China Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. B Correction to: Applied microbiology and biotechnology (2022) 106: 5449-5458 b https://doi.org/10.1007/s00253-022-12103-w In the published version, the affiliation order is incorrect. [Extracted from the article]

Dissolved oxygen (DO) is a key parameter for the production of L-tryptophan, and maintenance of appropriate DO levels can be used to increase the formation of L-tryptophan and reduce the accumulation of acetate and glutamate. In addition, controlling the level of DO by adjusting the feeding rate of glucose solution affects the concentration of glucose in the fermentation process. In this study, the effects of DO levels on L-tryptophan production were investigated, and four strategies of DO stage control were developed for use in L-tryptophan fermentation. The results indicate that the application of DO stage control I (20 % oxygen at 0-20 h, 30 % at 20-38 h) during L-tryptophan fermentation resulted in the highest dry cell weight (51.2 g/L) and production of L-tryptophan (46.8 g/L), which were 1.10 and 1.28 times as high, respectively, as those obtained during DO stage control III (50 % oxygen at 0-20 h and 20 % at 20-38 h). Additionally, the total glucose conversion percentage with DO stage control I was 17.2 %, which was 13.16 % higher than that of DO stage control III. Furthermore, the metabolic flux distribution with DO stage control I and III revealed greater carbon flux into the pentose phosphate pathway, while the flux of byproducts (acetate, glutamate, and lactate) was lower during DO stage control I. Finally, the flux of tryptophan with DO stage control I was 19.3 %, which was 1.79 times as high as that obtained with DO stage control III. [ABSTRACT FROM AUTHOR]

The production of L-tryptophan was increased by reducing acetate accumulation through a decrease in acetate kinase activity by gene deletion. The effects of disruption of the genes for acetate kinase ( ackA) and an enzyme with propionate/acetate kinase activity ( tdcD) on L-tryptophan production were investigated. The ackA and/or tdcD deletion mutants accumulated less acetate and more L-tryptophan than the parental strain. Furthermore, the production of L-tryptophan obtained with ackA- tdcD mutant were more than the mutants with a single deletion of ackA or tdcD, while higher production of L-tryptophan and lower concentration of acetate were accumulated in the ackA mutant than the mutant with a lesion in tdcD. In L-tryptophan fed-batch fermentation using the ackA- tdcD mutant, the excretion of acetate was reduced to 1.22 g/L, a 21.79 % reduction compared with the parental strain, and the production of L-tryptophan and glucose conversion rate were increased to 52.5 g/L and 47.9 g/L, respectively, which represented 6.49 % and 10.88 % increases compared with the parental strain, and the glucose conversion rate reached a high level of 21.2 %, which was 8.16 % higher than the parental strain. In addition, the metabolic flux analysis of TRTH and TRTHAT indicated that the carbon flux through EMP was decreased by 8.37 % and the carbon flux through PP was increased by 57.03 % in TRTHAT compared with TRTH. The flux of acetate and tryptophan formation of TRTHAT were 5.2 % and 17.3 %, which were 3.67-times lower and 1.75-times higher than these of TRTH, respectively. [ABSTRACT FROM AUTHOR]