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CitST is a typical two-component regulatory system that can regulate citrate utilization and is involved in the regulation of carbohydrate metabolism in Bacillus subtilis. B. subtilis is a kind of dominant species to bio-degum ramie fibers, which could degrade and utilize non-cellulose components as a carbon source during bio-degumming. This study aimed to explore the regulatory function of response regulator CitT from CitST two-component system when B. subtilis was used for extracting ramie fibers. The results showed that gene knocked-out of citT could significantly decrease the bio-degumming ability of B. subtilis. The enzymatic activity mensuration of functional enzymes revealed that deficient in CitT would remarkably reduce the enzymatic activity of pectinase, but there was a little difference in transcriptional levels of their encoding genes with qRT-PCR analysis, which further demonstrated that it was a lack of correlation between mRNA expression and enzymatic activities. The data also reflected that CitT specifically regulated the pectin degradation in bio-degumming of ramie fibers by analyzing the polysaccharide degradation rates of gum components. In conclusion, it was shown for the first time that CitT probably positively regulated the bio-degumming of ramie fibers and was an important regulator in pectin degradation. [ABSTRACT FROM AUTHOR]

Degumming is the most important step before kenaf bast fibers used in textile industry. Microbial degumming is an environmental protection and energy-saving technology to replace the conventional chemical degumming. Higher efficiency strains are the essential prerequisite to promote the application of microbial degumming technology. Generally, the screening and evaluation of strains for kenaf bast degumming were based on activity of functional enzymes produced by microorganism. In order to investigate the relationship between enzymatic activity and effect of kenaf bast degumming, strains DCE-01, 1101, B6, B7, and B8 were incubated in pure cultured, sterilized and non-sterilized degumming systems. After culturing for 16 h, functional enzymes for kenaf bast degumming (such as pectinase, neutral protease, xylanase, β-mannanase, laccase, lignin peroxidase and manganese peroxidase) were detected in the supernatant, and degumming effect of kenaf bast under sterilized and non-sterilized systems were evaluated respectively. Results revealed that strain DCE-01 was the best for kenaf bast degumming, though its enzymatic activity was not the highest among five strains. And the pretreatment of kenaf bast by high-pressure-steam sterilization could promote the degumming effect. This study suggested that there were limitations when screening or evaluating high-efficient strains for kenaf bast degumming with the guidance of enzymatic activity. [ABSTRACT FROM AUTHOR]

Transition metal oxides (TMOs) have excellent electrochemical properties. However, they are commonly associated with short cycle lives, agglomeration, and lower electrical conductivity. To ameliorate these drawbacks, porous rod-shaped CuO@Co3O4 has been synthesized through calcination with optimized oxidation temperature by using CuCo-MOF-74 as a template. Due to the porous structure, the CuO@Co3O4 electrode significantly increases the contact area with the electrolyte and greatly improves the reaction kinetics. As a result, the CuO@Co3O4 electrode exhibits excellent electrochemical performance with a specific capacitance of 545.5 F g−1 at a current density of 1 A g−1. The capacitance retention at 10 A g−1 was 88.7% after 10 000 cycles. Furthermore, an asymmetric supercapacitor (SC) has been assembled with CuO@Co3O4 as the positive electrode and commercial reduced graphene oxide (RGO) as the negative electrode, and the device has exhibited an energy density of 38.2 W h kg−1 at a power density of 1268.3 W kg−1. Impressively, the capacitance retention remained 83.2% even after 10 000 cycles at a high current density of 10 A g−1. This performance has demonstrated the potential of CuO@Co3O4 as an anode material for SCs. [ABSTRACT FROM AUTHOR]

Kenaf is one of the most important natural fiber crops. Traditional degumming with water retting causes serious environmental pollution and reduces the quality of fiber products. The development of kenaf industry is hindered by high production cost. Microbial degumming is suitable for kenaf bast degumming because of its high efficiency, energy conservation, low pollution, and high quality, among others. Through enrichment and screening from water sample, soil sample, and humus sample, we concentrated and identified 92 bacterial strains that could degrade kenaf bast colloid. The strains belonged to 11 genera and 16 species. Five of these strains did not produce cellulase and the weight loss rate of the kenaf bast fiber raw material was more than 20%. These strains belonged to Bacillus subtilis, Paenibacillus polymyxa, Clostridium acetobutylicum, Bacillus alcalophilus, and Erwinia chrysanthemi and were assigned with serial numbers from K1-K5, respectively. This study is the first to report the function of Bacillus pumilus, B. alcalophilus, Clostridium tertium, Brevibacillus brevis, Pectobacterium carotovora, E. chrysanthemi, and Tyromyces subcaesius in kenaf bast degumming. Pectinase and mannanase were the key enzymes in the degumming of kenaf bast. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The effects of wind shear and the tower shadow contribute to periodic fluctuations in the wind speed and aerodynamic torque, which cause several problems. This study develops an equivalent wind speed model for large-scale, n-bladed wind turbines that includes the wind shear and the tower shadow effects. The comprehensive model is used to derive the disturbance components of wind speed caused by wind shear, the tower shadow, their synthesis, and the equivalent wind speed and to delineate their spatial distributions in the rotor disk area. Simulation results reveal that the effects of wind shear, the tower shadow, and the equivalent wind speed on the disturbance components fluctuate periodically and are closely related to the wind turbine correlation parameters, such as the rotor radius, hub center height, tower radius, distance from the tower midline to the blade, wind shear exponent, and blade number. [ABSTRACT FROM AUTHOR]

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 Mn2+, Cu2+, Zn2+, Ca2+, Mg2+, and Al3+ and strongly inhibited by Ba2+ and Pb2+. Km and Vmax values for locust bean gum were 7.14 mg/mL and 107.5 μmol/min/mL versus 1.749 mg/mL and 33.45 µmol/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. [ABSTRACT FROM AUTHOR]

Abstract: LiFePO4/C composite materials have been synthesized from a low cost Fe2O3 precursor by a hydrothermal method to make LiFePO4(OH) in a first step followed by a fast calcination and carbon coating. This method combines the advantages of both hydrothermal and solid state synthetic methods. The as-prepared LiFePO4/C provides enhanced discharge capacity and cycling stability compared to LiFePO4 synthesized using a solid state method with the same precursors. Thus, the method to be described herein is a promising option in the search to reduce the cost of large-scale synthesis of LiFePO4/C for use in lithium-ion batteries, while maintaining adequate electrochemical performance. [Copyright &y& Elsevier]

Ramie bast is a kind of multipurpose biological material. Selective bio-degradation of ramie bast compounds is an important step to partial utilization of complex polysaccharides. Bacillus subtilis is a kind of dominant species with its ability to degrade ramie bast. In order to understand how polysaccharides were catalyzed and utilized in the metabolism of the bacteria, the proteome of B. subtilis strain 168 was analyzed in the presence of ramie bast as sole carbon source, and the cells were grown in glucose as a reference proteome. In total, 2129 proteins are identified, 1871 proteins were used for quantification between different growth conditions, and 363 proteins were differentially expressed under ramie bast and glucose culturing environment. The carbon source affected the abundance of proteins related to carbohydrate transporters via cell membrane, specific reducing sugars degradation pathway, and central carbon metabolism. qRT-PCR analysis revealed that the mRNA levels of four extracellular enzymes participated in polysaccharides degradation were upregulated under ramie bast condition. This study is the first time to uncover comprehensive information on the proteome response of B. subtilis to ramie bast degradation, and may provide important scientific basis for constructing engineering strains in selective extraction of polysaccharide components in ramie bast. [ABSTRACT FROM AUTHOR]

Abstract: A carbon-supported palladium catalyst modified by non-metal phosphorus (PdP/C) has been developed as an oxygen reduction catalyst for direct methanol fuel cells. The PdP/C catalyst was prepared by the sodium hypophosphite reduction method. The as-prepared Pd nanoparticles have a narrow size distribution with an average diameter of 2nm. Energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) results indicate that P enters into the crystal lattice of Pd and forms an alloy. The PdP/C catalyst has an oxygen reduction reaction (ORR) activity comparable to the commercial Pt/C catalyst and a higher activity than the Pd/C catalyst synthesized by the conventional NaBH4 reduction method. Its high catalytic activity can be attributed to its small size, lower relative crystallinity, and the formation of PdP alloy. [Copyright &y& Elsevier]

Microbial treatment of natural fibers is a preferred alternatives in ramie degumming process as compared to conventional chemical degumming technology with alkaline treatment at high temperature. Usually, it is difficult to degrade the noncellulosic components of ramie bast completely with a single strain in the mono-culturing degumming system. Microbial coculture strategy has been widely used in biotechnology, especially in the degradation of biological materials. In the present study, five strains for ramie degumming were identified as Dickeya dadantii strain DCE-01, Bacillus subtilis strain 1101, Bacillus sp. B6, Bacillus cereus strain B7, and Bacillus cereus strain B8 by sequencing of 16 S rRNA genes. Enzymatic activities characterization, ramie degumming experiments with mono-culturing systems, and the evaluation of strain compatibility showed that group DCE-01/B7 were the most suitable pairs for the construction of bacterial coculturing system. After preliminary optimization of coculturing fermentation condition, the weight loss weight ratio of ramie fibers was 27%, which was increased 13.6% and 8.9% while compared to mono-culturing systems of strain B7 and DCE-01 respectively. These data highlighted the benefit of microbial coculture strategy in the application of ramie degumming process, and indicated a higher-efficiency alternative for the microbial degumming in the textile industry. [ABSTRACT FROM AUTHOR]

In this research, nano Mn 3 O 4 particles are in situ formed on the surface and between the interlayer of Ti 3 C 2 T x MXene, which has been pretreated by the intercalation of K+ ion. Ti 3 C 2 T x MXene can not only provide abundant actives sites and high conductivity but also hinder the structure damage of Mn 3 O 4 during the charging and discharging process, so that batteries equipped with K-Ti 3 C 2 @Mn 3 O 4 cathode exhibit outstanding electrochemical performance. [Display omitted] 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. [ABSTRACT FROM AUTHOR]

Atypical meningioma is a specific type of meningioma that is relatively rare in clinical practice. The clinical manifestations of atypical meningioma are non-specific and the imaging findings are similar to those for other intraspinal space-occupying lesions. It is usually misdiagnosed as schwannoma or metastases, and it is necessary to rely on intraoperative findings and pathological examination to confirm the diagnosis. Atypical meningioma invading the intervertebral foramen and causing bone destruction is rare. The present study describes the case of a patient with cervical intraspinal atypical meningioma combined with cervical bone destruction. A 50-year-old female patient presented with numbness of the extremities with unstable walking, and underwent magnetic resonance imaging (MRI) of the cervical spine. MRI showed a space-occupying lesion in the spinal canal at the C2-4 level. The patient underwent cervical intraspinal lesion resection, and postoperative pathology confirmed atypical meningioma (World Health Organization grade II). The patient received dehydration and hormone therapy, and was discharged after the symptoms improved. Radiotherapy was performed 2 months after discharge. Cervical MRI 3 months after the operation showed that the tumor resection was satisfactory. To the best of our knowledge, the present study is the first to report on this specific type of meningioma. The present case report may provide useful information for clinicians to diagnose and treat the disease. [ABSTRACT FROM AUTHOR]

It is a challenging task to perform the non-linear system state recognition and safety monitoring under strong noise and complex excitation, to tackle this problem, we innovatively propose the variational mode decomposition multiscale holographic transfer entropy statistics (VMTES) method based on the energy transfer relationship between non-linear system signals. The VMTES is a method that measures the information flow direction and coupling degree between non-linear systems, which can precisely measure the slight changes of energy transfer of a mechanical system, accurately assess the slight mutation of dynamical behaviors and status change of a mechanical system and therefore realize fault location and quantification of the non-linear rotating machinery system. The damage severity and direction of the measure point can be precisely described with the VMTES damage assessment indicator, providing the reliable basis for the structural health monitoring and fault diagnosis of the mechanical system. By applying the result to the state recognition of a chaotic system and the structural health monitoring of a rotating machinery system, we can see from the experimental results that the VMTES can effectively detect the fault of gears and rolling bearings under several working conditions. Based on the experiment, we also explain how this method simultaneously locate and quantify the non-linear vibration caused by the fault. • We develop VMTES method for rotating machinery structural health monitoring. • A damage evaluation index of rotating machinery is proposed. • We develop a visual damage nephogram for mechanical systems. • The effectiveness of the method is verified by simulation and experiments. [ABSTRACT FROM AUTHOR]

The blade aerodynamic asymmetry fault must be detected early due to its important effect on wind turbines. This paper develops a fault diagnosis approach based on the current and power characteristics of a Doubly fed induction generator (DFIG). First, the blade aerodynamic characteristics and the influence on the nacelle and tower vibration under an aerodynamic asymmetry fault are analysed and an improved Blade element moment (BEM) method considering the blade, nacelle and tower vibration is proposed to calculate the aerodynamic torque. Then, the electrical characteristics of the DFIG are analysed. The output power is shown to decrease with oscillation when aerodynamic asymmetry occurs. In addition, the same modulation harmonic frequency as the blade rotating frequency exists in the stator and the rotor current. Finally, simulations under constant and stochastic wind conditions via MATLAB/Simulink show the effectiveness of the proposed method in this paper. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. Highlights: The growth of Prevotella was initially inhibited with the kenaf retting. Acinetobacter can promote the degumming process of kenaf. The upregulation of P37698, P52040 and P54937 proteins is a sign in the degumming. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We demonstrate the design, fabrication and characterization of a highly efficient multichannel W3 Y-branch filter in a two dimensional triangular-lattice photonic crystal slab. The coupling properties between high-order waveguide modes and fundamental resonant modes are investigated. By finely adjusting the size of resonant cavities, four higher-order mode channels with different output wavelengths are experimentally realized, which is in agreement with the theoretical simulations. The results show that this kind of filter may be useful in optical integrated circuits with high coupling and transmission efficiency. [ABSTRACT FROM AUTHOR]

Highlights: [•] Frequency tuned air-slot mode-gap nanocavities are obtained. [•] Frequency can be continuously tuned almost covering the entire mode gap region. [•] The cavity’s resonant frequency is very sensitive to the shape alteration. [ABSTRACT FROM AUTHOR]

This work is intended to describe the design aspects and to characterize the functionality of a novel flip-chip (FC) structure applicable for THz camera assembling. The proposed FC structure consists of a thin-film ceramic layer sandwiched between a GaAs substrate and PCB board. There is an air chamber underneath the antenna to protect the air bridge of Schottky Diode located on GaAs substrate and improve antenna performance. In particular, we have used the novel FC structure simulation result as the excitation source for THz camera lens simulation. Even if the FC structure cause antenna performance to deteriorate, the high gain can be obtained at 0.34 THz and 0.22 THz (λ = 880 and 1360 μm) from the FEKO simulation results. The FC structure mode and the without FC structure (wire bonding structure) mode were characterized using same test system, they show good match in proposed frequency range. [ABSTRACT FROM AUTHOR]

We present a novel and simple design of an air-slot mode-gap photonic crystal (PC) nanocavity by introducing a linear air slot to the center of a line-defect waveguide in a two dimensional triangular-lattice silicon PC slab. A high quality factor ( Q factor) of 8.42×10 and an ultrasmall mode volume of 0.998 cubic wavelength are achieved in an optimized air-slot nanocavity which is a suitable choice for the strong matter-field interaction in free space. The high Q cavities with ultrasmall mode volume are important for applications such as quantum computation and nonlinear optics. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]