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Manganese-based cathodes are competitive candidates for state-of-the-art aqueous zinc-ion batteries (AZIBs) because of their easy preparation method, sufficient nature reserve, and environmental friendliness. However, their poor cycle stability and low rate performance have prevented them from practical applications. In this study, Mn 3 O 4 nanoparticles were formed in situ on the surface and between the interlayers of Ti 3 C 2 T x MXene, which was pretreated by the intercalation of K + ions. Ti 3 C 2 T x MXene not only provides abundant active sites and high conductivity but also hinders the structural damage of Mn 3 O 4 during charging and discharging. Benefiting from the well-designed K-Ti 3 C 2 @Mn 3 O 4 structure, the battery equipped with the K-Ti 3 C 2 @Mn 3 O 4 cathode achieved a maximum specific capacity of 312 mAh/g at a current density of 0.3 A/g and carried a specific capacity of approximately 120 mAh/g at a current density of 1 A/g, which remained stable for approximately 500 cycles. The performance surpasses that of most reported Mn 3 O 4 -based cathodes. This study pioneers a new approach for building better cathode materials for AZIBs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Tumefactive demyelinating lesions (TDLs) are rare and specific types of inflammatory demyelinating lesions. Its clinical manifestations are nonspecific, and the imaging findings are similar to those of other intracranial space-occupying lesions, which are usually misdiagnosed as tumors or abscesses and require a pathologic examination to confirm the diagnosis. Tumefactive demyelinating lesions after kidney transplantation are even rarer. This article reports a case of TDLs after kidney transplantation. A 60-year-old female patient underwent kidney transplantation 15 years ago and took anti-rejection drugs such as tacrolimus, tacrolimus, and corticosteroids after surgery. The patient was admitted with headache and left limb weakness, and magnetic resonance imaging of the head showed multiple space-occupying lesions with surrounding edema. The patient underwent a stereotactic biopsy of the encephalopathy lesion, and postoperative pathology confirmed TDLs. She was treated with corticosteroids and discharged after the improvement of her symptoms. Here, to our knowledge, we report the first case of TDLs after kidney transplantation. We report this case to provide clinicians with useful information on intracranial demyelinating disease after kidney transplantation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Data on the microbial community and functional proteins associated with degumming in kenaf remains scant. Here, we analyzed the microbial communities associated with kenaf (Hibiscus cannabinus) bast fibers during retting to identify potential candidate degumming bacteria. Retting liquids were collected and analyzed at 0 days, 10 days, and 34 days and then evaluated the yield and quality of kenaf fiber at the different retting times. Besides, the microbial communities were characterized using metagenomic and proteomic analysis by LC-MS/MS technology., Results: The data showed that increase in the retting time significantly improves the softness, dispersion, and fiber whiteness of the kenaf fiber. The relative abundance of Acinetobacter increased from 2.88% at the baseline to 6.64% at the 34th retting. On the other hand, some members of Clostridium were reduced from 3% at the baseline to 2% at the 34th retting. Analysis of carbohydrate active enzymes showed constant changes in the utilization of carbohydrates. Besides, benzoquinone reductase, cellobiose dehydrogenase, glucose 1-oxidase, aryl alcohol oxidase and alcohol oxidase were the top five most abundant enzymes in the retting liquids. This present results demonstrated that the expressions of B7GYR8, Q6RYW5 and Q6FFK2 proteins were suppressed in Acinetobacter with the retting time. On the contrary, P05149 was upregulated with the retting time. In Clostridium, P37698, P52040 and P54937 proteins were upregulated with the retting time., Conclusion: In addition, bacteria Acinetobacter and Clostridium might be playing important roles in the kenaf degumming process. Similarly, up-regulation of P37698, P52040 and P54937 proteins is an important manifestation and mediates important roles in the degumming process., (© 2022. The Author(s).)

In order to obtain a thermostable pectate lyase for ramie degumming, a rational design based on structural analysis was carried out on a novel pectate lyase (Pel419) derived from the Dickeya Dadantii DCE-01 for high-efficiency ramie degumming. A total of five potential amino acid sites were chosen to replace residues. Then, the mutant enzymes were subjected to the heterologous expressions in Escherichia coli and their enzymatic characteristics were determined. The optimal reaction temperature for the five mutants kept consistent with that for the wild type. The enzyme activity and thermal stability of mutant V52A were significantly improved. Meanwhile, the weight loss rate obtained by V52A with the best enzymatic characteristics in the ramie degumming process at 50 °C is comparable with that obtained by commercial cotton-ramie processing pectinases, indicating that V52A was a potential industrial enzyme that could be applied to large-scale ramie degumming. In this study, the biological functions of conservative residues of Pel419 were preliminarily explored. The mutant V52A with both enzymatic activity and improved heat resistance was acquired, providing a superior material for developing enzyme preparations of ramie degumming, and rendering an effective method for the rational design aiming to improve the thermostability of pectate lyase.

The research and development of bio-degumming technology is under a slow progress due to the shortage of proper efficient bacterial strains and processes. A degumming bacterial strain-Pectobacterium wasabiae (PW)-with broad-spectrum degumming abilities was screened out in this study. After the fermentation for 12 h, the residual gum contents of kenaf bast, ramie bast, hemp bast, flax bast, and Apocynum venetum bast were all lower than 15%. This bacterial strain could realize the simultaneous extracellular secretion of pectinase, mannase, and xylanase with the maximum enzyme activity levels of 130.25, 157.58, and 115.24 U/mL, respectively. The optimal degumming conditions of this bacterial strain were as follows: degumming time of 12 h, bath ratio of 1:10, temperature of 33 °C, and inoculum size of 2%. After the bio-degumming through this bacterial strain, the COD in wastewater was below 4000 mg/L, which was over 60% lower than that in boiling-off wastewater generated by chemical degumming. This technology achieves higher efficiency, higher quality, and lower pollution., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

It is a difficult task to analyze the coupling characteristics of rotating machinery fault signals under the influence of complex and nonlinear interference signals. This difficulty is due to the strong noise background of rotating machinery fault feature extraction and weaknesses, such as modal mixing problems, in the existing Ensemble Empirical Mode Decomposition (EEMD) time-frequency analysis methods. To quantitatively study the nonlinear synchronous coupling characteristics and information transfer characteristics of rotating machinery fault signals between different frequency scales under the influence of complex and nonlinear interference signals, a new nonlinear signal processing method-the harmonic assisted multivariate empirical mode decomposition method (HA-MEMD)-is proposed in this paper. By adding additional high-frequency harmonic-assisted channels and reducing them, the decomposing precision of the Intrinsic Mode Function (IMF) can be effectively improved, and the phenomenon of mode aliasing can be mitigated. Analysis results of the simulated signals prove the effectiveness of this method. By combining HA-MEMD with the transfer entropy algorithm and introducing signal processing of the rotating machinery, a fault detection method of rotating machinery based on high-frequency harmonic-assisted multivariate empirical mode decomposition-transfer entropy (HA-MEMD-TE) was established. The main features of the mechanical transmission system were extracted by the high-frequency harmonic-assisted multivariate empirical mode decomposition method, and the signal, after noise reduction, was used for the transfer entropy calculation. The evaluation index of the rotating machinery state based on HA-MEMD-TE was established to quantitatively describe the degree of nonlinear coupling between signals to effectively evaluate and diagnose the operating state of the mechanical system. By adding noise to different signal-to-noise ratios, the fault detection ability of HA-MEMD-TE method in the background of strong noise is investigated, which proves that the method has strong reliability and robustness. In this paper, transfer entropy is applied to the fault diagnosis field of rotating machinery, which provides a new effective method for early fault diagnosis and performance degradation-state recognition of rotating machinery, and leads to relevant research conclusions.

The ubiquitous Acinetobacter baumannii is an important and troublesome pathogen of nosocomial infection. Multidrug-resistant A baumannii meningitis is very difficult to treat, usually with high mortality. The disease is generally associated with craniotomy, but rarely with lumbar puncture. However, in our case, a 45-year-old male construction worker suffered multidrug-resistant A baumannii meningitis associated with lumbar puncture. The patient responded poorly to the initial treatment with an intravenous infusion of tigecycline. However, later treatment with an intrathecal injection of tigecycline (concentration 1 mg/mL) at a dose of 10 mg every 12 hours proved to be highly efficacious. Thus, intrathecal injection of tigecycline should be seriously considered as a treatment for multidrug-resistant A baumannii meningitis., Competing Interests: Competing interests: None declared.

Objectives: To research the inherent properties of the co-expression of three types degumming-related enzymes and breed more powerful degumming strains., Results: Six tandem multimers of the pectate lyase gene, the xylanase gene, and the endo-1,4-β-mannanase gene, which are essential for degumming process, were co-expressed and evaluated in Escherichia coli BL21(DE3). The xyl91 gene had a synergistic effect with endo-1,4-β-mannanase and pectate lyase from DCE-01, when xyl gene was replaced with xyl91 in the multimer. The recombinant pET-pxm(91x) was selected and transformed into the original degumming strain DCE-01, which led to an enzymatic activity improvement. Furthermore, the weight loss, reducing sugar and COD value of the sample treated with the new engineered strain pET-pxm(91x)/DCE-01 increased to 22.5 %, 460 mg ml -1 and 4.9, respectively., Conclusions: The co-expression of degumming-related enzyme genes may be applied in industrial tests and represents a novel direction for bio-degumming research.

Among industrial fiber crops, jute is ranked second to cotton in terms of yield and planting area worldwide. The traditional water retting and chemical semi-degumming methods restrict the development of the jute industry. Jute fiber can be extracted from jute bast through mechanical rolling (preprocessing), culture of bacteria, soaking fermentation (liquor ratio = 10, inoculum size = 1 %, temperature = 35 °C, and time = 15 h), inactivation, washing, and drying. Pectobacterium sp. DCE-01 secretes key degumming enzymes: pectinase, mannase, and xylanase, which match well the main non-cellulosic components of jute bast. Compared with the traditional water retting degumming, the bio-degumming cycle is shortened from more than 10 days to 15 h. The proposed bio-degumming achieved higher efficiency and lower pollution than water retting and chemical semi-degumming.

β -mannanase has shown compelling biological functions because of its regulatory roles in metabolism, inflammation, and oxidation. This study separated and purified the β -mannanase from Bacillus subtilis BE-91, which is a powerful hemicellulose-degrading bacterium using a "two-step" method comprising ultrafiltration and gel chromatography. The purified β -mannanase (about 28.2 kDa) showed high specific activity (79, 859.2 IU/mg). The optimum temperature and pH were 65°C and 6.0, respectively. Moreover, the enzyme was highly stable at temperatures up to 70°C and pH 4.5-7.0. The β -mannanase activity was significantly enhanced in the presence of Mn 2+ , Cu 2+ , Zn 2+ , Ca 2+ , Mg 2+ , and Al 3+ and strongly inhibited by Ba 2+ and Pb 2+ . K m and V max values for locust bean gum were 7.14 mg/mL and 107.5  μ mol/min/mL versus 1.749 mg/mL and 33.45  µ mol/min/mL for Konjac glucomannan, respectively. Therefore, β -mannanase purified by this work shows stability at high temperatures and in weakly acidic or neutral environments. Based on such data, the β -mannanase will have potential applications as a dietary supplement in treatment of inflammatory processes.

Xylanases catalyze the hydrolysis of xylan, a major hemicellulose component of cell wall besides cellulose in most plant species. To extract cellulose fibers, it will be invaluable to screen for more effective xylanase-producing microorganisms. In this paper a new strategy for easy screening of xylanase-producing strains from the degumming line was presented. Using this strategy, a weak-acidic, cellulase-free xylanase from Bacillus subtilis has been isolated, purified and characterized. The xylanase showed high specific activity (36,633.4 U/mg), presented stable characteristics and can be separated and purified simply, with molecular weight 23.3 kD, pI 9.63. It reached its optimal activity at pH 5.8 and 60 °C, and retained over 80% of its maximal activity after pre-incubation at temperature 60 °C or pH 4.6 ~ 6.4. Also, a two-step purification procedure based on the combination of ultrafiltration and gel filtration chromatography was introduced and described, achieving 17-fold purification with 68.11% yield., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A Gram-negative, non-motile, non-spore-forming bacterial strain designated IBFC2009(T) was isolated from soil of a bamboo plantation. The strain could grow at 11 degrees C approximately 39 degrees C, pH 6.0-9.0, and in the presence of 0 approximately 5% NaCl. Based on 16S rRNA gene sequence analysis, Strain IBFC2009(T) belonged to the genus Sphingobacterium and showed the highest sequence similarity of 94.6% (S. composti T5-12(T)) with the type strains within the genus. The major fatty acids were summed feature 3 (iso-C(15:0) 2-OH and/or C(16:1) omega7c, 34.4%), iso-C(15:0) (22.4%), C(16:0) 3-OH (15.2%), and iso-C(17:0) 3-OH (12.8%). The G+C content of the genomic DNA was 41.0 mol%. According to the phenotypic and genotypic characteristics, Strain IBFC2009(T) should represent a novel species of the genus Sphingobacterium, for which the name Sphingobacterium bambusae sp. nov. is proposed. The type strain is IBFC2009(T) (=CCTCC AB 209162(T) =KCTC 22814(T)).