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Magnetic bearings are widely used in fields such as fluid machinery, aerospace, and marine vessels due to their properties of non-mechanical contact. Due to errors in manufacturing and assembly, unbalanced forces will be generated when the magnetic suspension rotors rotate, especially at high speed, which can easily cause strong vibration of the equipment. The control compensation algorithm of minimum displacement for the rotor is to adjust the control current of the magnetic bearing based on speed and unbalanced quantity, so that the rotor rotates around its centre of the geometric as much as possible, in order to reduce rotor displacement vibration and ensure the reliable and safe operation of the equipment. However, owing to the presence of speed changes and phase lag, it is necessary to continuously and repeatedly calculate the unbalanced compensation coefficient, which increases the computational complexity and affects the control effect of the magnetic suspension rotor. Therefore, this paper proposes a method based on LMS (Least Mean Square) and polynomial fitting to calculate the unbalanced compensation coefficient, obtaining the compensation amplitude and phase of the unbalanced vibration of the magnetic suspension rotor at different speeds, solving the problem of active unbalanced vibration control for the magnetic suspension rotor at any speed, and providing guarantee for the application of the magnetic suspension rotor in high-speed rotating machinery. [ABSTRACT FROM AUTHOR]

In order to precisely diagnose the fault type of rotating machinery, a fault diagnosis method for rotating machinery based on improved multiscale attention entropy and random forests is proposed in this study. Firstly, a nonlinear dynamics technique without hyperparameters namely multiscale attention entropy is proposed for measuring signal complexity by extending attention entropy to multiple time scales. Secondly, aiming at the insufficient coarse-graining of multiscale attention entropy, composite multiscale attention entropy is exploited to extract the features of rotating machinery faults. Then, t-distributed stochastic neighbor embedding is used to overcome the feature redundancy problem by reducing the dimension of the extracted features. Finally, the reduced-dimensional features are inputted into the random forests model to complete fault pattern recognition of rotating machinery. The results of the experiment indicate that the proposed method achieves the optimal diagnostic performance on two different fault datasets respectively, showing an extremely competitive advantage in comparison with conventional diagnosis models. Meanwhile, the proposed method is adopted to the actual hydropower unit without misjudgment, which verifies its strong adaptability. The research proposes a novel method for detecting faults in rotating machinery such as hydropower units. [ABSTRACT FROM AUTHOR]

Background: Although gastric surgery can significantly improve blood glucose homeostasis in type 2 diabetes mellitus (T2DM), its mechanism remains unclear. This study evaluated the role of intestinal glucose sensing, glucose transport, and metabolism in the alimentary limb (A limb) of T2DM rats after duodenal jejunal bypass (DJB) surgery. Methods: A T2DM rat model was induced via a high-glucose high-fat diet and low-dose streptozotocin injection. The diabetic rats were divided into two groups: the DJB surgery (T2DM-DJB) group and the sham surgery (T2DM-Sham) group. Wistar rats were used as wild-type control (Control). Small animal PET was used to assess the change in glucose metabolic status in the intestine. The intestinal villi height and the number of EECs after DJB were evaluated. The expressions of sweet taste receptors (T1R2/T1R3), glucose transporters (SGLT1/GLUT2), and key enzymes involved in glucose metabolism (HK2, PFK2, PKM2, G6Pase, and PCK1) in the A limb after DJB was detected by Western blot and qRT-PCR. Results: Small animal PET analysis showed the intestinal glucose metabolism increased significantly 6 weeks after DJB surgery. The intestinal villi height and the number of EECs in the A limb 6 weeks after surgery increased significantly in T2DM-DJB rats comparing to T2DM-Sham rats. The mRNA and protein expression of T1R1/T1R3 and SGLT1/GLUT2 were downregulated in DJB-T2DM rats, while enzymes involved in glucose metabolism was upregulated in the A limb in T2DM-DJB rats. Conclusion: Proximal intestinal glucose sensing and metabolism play an important role in blood glucose homeostasis by DJB. [ABSTRACT FROM AUTHOR]

Here, we report two novel enteroviruses, designated as SD-S67 and SD-S68, isolated from a goat farm. Their complete genome sequences were determined and found to be 7455 and 7465 nucleotides in length, respectively. Molecular characterization revealed that SD-S67 is closely related to bovine enterovirus strain 261 and that SD-S68 to caprine enterovirus strain CEV-JL14. Phylogenetic analysis showed that SD-S67 clustered with members of the species Enterovirus F, and that SD-S68 clustered with enteroviruses of goats and sheep. Recombination analysis showed that SD-S67 is likely to have undergone several recombination events in the process of its evolution. To the best of our knowledge, this is the first report of an enterovirus F isolate from a goat and of a coinfection with enteroviruses of different species in the same goat herd. [ABSTRACT FROM AUTHOR]

This paper proposes a long-stroke linear switched reluctance machine (LSRM) with a primary and a secondary translator for industrial conveyance applications. The secondary one can translate according to the primary one so that linear compound motions can be achieved. Considering the fact that either one translator imposes a time-variant, nonlinear disturbance onto the other, the selftuning position controllers are implemented for the proposed linear compound machine and experimental results demonstrate that the absolute steady-state error values can fall into 0.03 mm and 0.05 mm for the secondary and primary translator, respectively. A composite absolute precision of less than 0.6 mm can be achieved under the proposed control strategy [ABSTRACT FROM AUTHOR]

Objectives: To optimize the production of active inclusion bodies (IBs) containing human d-amino acid oxidase (hDAAO) in Escherichia coli. Results: The optimized initial codon region combined with the coexpressed rare tRNAs, fusion of each of the N-terminal partners including cellulose-binding module, thioredoxin, glutathione S-transferase and expressivity tag, deletion of the incorporated linker, and improvement of tRNA abundance affected the production and activity for oxidizing d-alanine of the hDAAO in IBs. Compared with the optimized fusion constructs and expression host, IBs yields and activity were increased to 2.6- and 2.8-fold respectively by changing the N-terminal codon bias of the hDAAO. The insoluble hDAAO codon variant displayed the same substrate specificity as the soluble one for oxidizing d-alanine, d-serine and d-aspartic acid. The freshly prepared hDAAO codon variant was used for analyzing the l-serine racemization activity of the bacterially expressed maize serine racemase. Conclusions: Optimization of the N-terminal codon bias combined with the coexpression of rare tRNAs is a novel and efficient approach to produce active IBs of the hDAAO. [ABSTRACT FROM AUTHOR]

In this study, four fusion proteins were designed, in which the N-terminal cellulose-binding module as the affinity tag was immobilized on the regenerated amorphous cellulose (RAC), and the release of the C-terminal colored proteins was detected easily and rapidly after on-resin cleavage using the free tobacco etch virus protease (TEVp) variant, or the immobilized cognate protease with a binding capacity of up to 220 mg protein per gram of RAC. The enhanced stability and repetitive use of the immobilized TEVp compensated slight loss of the catalytic efficiency toward the soluble protein substrate. On-resin cleavage and purity of the released target proteins are related to the context of the fusion tag, the incorporated linker composition, and the colored protein. Owing to low cost and high binding capacity of the RAC, the TEVp immobilized on the resin is an ideal alternative for removing fusion tag. The colored proteins are easily monitored in the on-resin process of fusion proteins, and rapid separation from RAC. [ABSTRACT FROM AUTHOR]

In this study, we asked participants to "describe their sexual orientation" in an open-ended measure of self-generated sexual orientation. The question was included as part of the New Zealand Attitudes and Values Study (N = 18,261) 2013/2014 wave, a national probability survey conducted shortly after the first legal same-sex marriages in New Zealand. We present a two-level classification scheme to address questions about the prevalence of, and demographic differences between, sexual orientations. At the most detailed level of the coding scheme, 49 unique categories were generated by participant responses. Of those who responded with the following, significantly more were women: bisexual (2.1 % of women, compared to 1.5 % of men), bicurious (0.7 % of women, 0.4 % of men), and asexual (0.4 % of women and less than 0.1 % of men). However, significantly fewer women than men reported being lesbian or gay (1.8 % of women, compared to 3.5 % of men). Those openly identifying as bicurious, bisexual, or lesbian/gay were significantly younger than those with a heterosexual orientation. This study shows diversity in the terms used in self-generated sexual orientations, and provides up-to-date gender, age, and prevalence estimates for the New Zealand population. Finally, results reveal that a substantial minority of participants may not have understood the question about sexual orientation. [ABSTRACT FROM AUTHOR]

In this study, five fusion tags affecting soluble production and cleavage activity of the tobacco etch virus (TEV) protease (TEVp) variant in Escherichia coli strains BL21 (DE3) and Rosetta™ (DE3) are investigated. Combination of the augmenting rare transfer RNAs (tRNAs) and the fused expressivity tag ( N-terminal seven amino acid residues of E. coli translation initiation factor II) promotes the soluble TEVp partner expressed at relatively high level. Attachment of the maltose-binding protein (MBP) tag increases soluble expression of the protease released from the fusion protein in E. coli cells, but the incorporated TEVp recognition sequence slightly decreases expressivity of the fusion construct. Except for the green fluorescent protein, the attached expressivity tag shows less efficiency than the MBP tag in enhancing expression levels of the selected five target proteins in the Rosetta™ (DE3) cells under different induction conditions. Our results identified that high-level production of the functional target protein as the fusion partner in E. coli is combined with the intrinsic property of fusion tag, fusion protein stability, inherent folding of target protein, rare tRNA abundance, and the incorporated linker. Purified TEVp fusion constructs with the N-terminal expressivity tag, as well as the MBP partner, are the ideal alternatives for removing fusion tag. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus, a marine pathogen, is a causative agent of gastroenteritis in humans after consumption of contaminated seafood. In recent years, infections with V. parahaemolyticus have become an increasingly frequent factor in microbial food poisoning; therefore, it is urgent to figure out ways to control Vibrio parahaemolyticus. Endolysins, lytic enzymes encoded by bacteriophages, have been regarded as a therapeutic alternative to antibiotics in control of bacterial growth and have been successfully utilized in various areas. Here, we report the full genome sequence of the novel phage qdvp001, which lyses Vibrio parahaemolyticus 17802. The qdvp001 genome consists of a 134,742-bp DNA with a G+C content of 35.35 % and 227 putative open reading frames. Analysis revealed that the qdvp001 open reading frames encoded various putative functional proteins with a putative endolysin gene (ORF 60). No holin genes were identified in qdvp001. ORF 60 was cloned and expressed. The results showed that the purified endolysin Lysqdvp001 had a high hydrolytic activity toward Vibrio parahaemolyticus and a broader spectrum compared to that of the parental bacteriophage qdvp001. Thus, purified endolysin Lysqdvp001 has a potential to be used as an antibacterial agent in the future. [ABSTRACT FROM AUTHOR]

The process control of industrial electroslag remelting production is addressed in this work. This article proposes a mechanism-based model using electrode displacement to estimate the melt rate, designs the remelting process control system, and uses practical application data to verify the validity of the model. The soft measurement of the melt rate based on mechanism modeling is proved to be an economical and reliable solution to the online melt rate estimation and control for large industrial electroslag remelting furnaces. [ABSTRACT FROM AUTHOR]

secondary amino group modified MCM-41 (mobile crystalline material number 41) was synthesized and used as a support for the immobilization of a salen oxovanadium complex via a multi-grafting method. The immobilized complex was characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), N adsorption and ICP analysis techniques. The immobilized complex was found to be an effective catalyst for oxidation of cyclohexane using HO as an oxidant under mild conditions. A conversion of 45.5% of cyclohexane was obtained with a selectivity of 100% of the cyclohexanone/cyclohexanol mixture when the reaction was run at 60 °C for 12 h in acetonitrile. Decomposition of the complex, which leads to the deactivation of the catalyst, is observed and a decomposition mechanism is discussed. [ABSTRACT FROM AUTHOR]

chiral Manganese (III) salen complex was immobilized on the walls of MCM-41 (mobile crystalline material) through the multi-grafting method. The immobilized complex was characterized by XRD, FTIR, UV-Vis, ICP and Nitrogen sorption, and was applied to the asymmetric epoxidation of unfuctionalized alkenes including 1,2-dihydronaphthalene, α-methylstyrene, cis- β-methylstyrene, styrene using NaClO and m-chloroperbenzoic acid ( m-CPBA) as oxidants respectively. The immobilized complex showed good activity and enantioselectivity in the epoxidation of 1,2-dihydronaphthalene by using NaClO as oxidant. It could also be run for 4 times in the epoxidation of α-methylstyrene without obvious loss of activity or enantiomeric excess. [ABSTRACT FROM AUTHOR]

A method based on capillary zone electrophoresis with electrochemical detection (CE-ED) has been employed for the separation and determination of epicatechin, scopoletin, quercetin and gallic acid in Toona sinensis (A. Juss) Roem leaves. Seasonal variations of these ingredients in T. sinensis (A. Juss) Roem leaves collected in April, June and August, were discussed. Several important factors including running buffer acidity, separation voltage, working electrode potential and etc., were evaluated to acquire optimum analysis conditions. Under the selected optimum conditions, these analytes could be well separated. Good linear relationship was established between the peak current and the concentration of each analyte over 2–3 orders of magnitude with detection limits (S/N = 3) ranging from 4.00 × 10−8 to 1.73 × 10−7g mL−1. The proposed method has been successfully applied for the evaluation of the seasonal content variation of these four active ingredients in T. sinensis (A. Juss) Roem leaves with satisfactory results. [ABSTRACT FROM AUTHOR]

A secondary amino-modified mesoporous molecular sieve MCM-41 was obtained by reaction of bis(3-(triethoxysilyl)propyl)amine with MCM-41. The chiral Salen-Mn (III) complex was anchored onto the modified MCM-41 by a multi-step grafting method and two heterogenized catalysts with different Mn contents were obtained. The catalysts were characterized by XRD, N2 adsorption, ICP, FT-IR and DR UV-Vis. Their catalysis on asymmetric epoxidation of several olefins was studied with NaCIO and m-CPBA as oxidants respectively. It was found that both the activity and enantioselectivity of the catalysts decreased after the homogeneous catalyst was heterogenized. The reasons resulting in the decrease of catalytic performance were discussed. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "The Diversity and Prevalence of Sexual Orientation Self-Labels in a New Zealand National Sample" by Lara M. Greaves, Fiona Kate Barlow, Carol H. J. Lee, Correna M. Matika, Weiyu Wang, Cinnamon-Jo Lindsay, et al., published in an earlier issue of the journal.

Nano-scaled polyoxometalates (POMs) clusters with sizes ranging from 1 to 10 nm attract tremendous attention and have been extensively studied due to POMs’ fascinating structural characteristics and prospects for wide-ranging applications. As a unique class of nanoparticles with well-defined structural topologies and monodispersed masses, the structures and properties of POMs in both bulk state and solutions have been explored with several well-developed protocols. Small-angle X-ray scattering (SAXS) technique, as a powerful tool for studying polymers and nanoparticles, has been recently extended to the investigating of solution behaviors of POMs. In this mini-review, the general principle and typical experimental procedures of SAXS are illustrated first. The applications of SAXS in characterizing POMs’ morphology, counterion distribution around POMs, and short-range interactions among POMs in solutions are highlighted.ᅟ [ABSTRACT FROM AUTHOR]