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In order to accurately evaluate the performance of a traction machine/drive system, it is necessary to have an accurate excitation source which considers current harmonics. In this paper, four machine/drive systems with different excitation sources have been modeled, simulated, and studied to evaluate the effects on permanent magnet synchronous machines (PMSMs) from different perspectives. In Model I, the excitation is an ideal sinusoidal current source with no harmonics. Model II is excited by an ideal sinusoidal voltage source regardless of the pulse width modification's (PWM's) influence. Model III takes into account the influence of current harmonics under space vector pulse width modulation (SVPWM) control. Model IV is based on the equivalent circuit extraction (ECE) model (a look-up table motor model). We simulate these four models and study the characteristics of the excitation sources, based on the observations of current harmonics, torque, electromagnetic force, computation time, and efficiency. Experiments are also conducted to show that Model III allows the most precise study of the considered system. Model IV is a good substitution, providing similar results with a shorter running time. [ABSTRACT FROM AUTHOR]

Actively controlling the phase of a terahertz (THz) wave is of great significance for beaming, tunable focusing, and holography. We present a THz phase modulator based on an electrically triggered vanadium dioxide ( V O 2 ) reconfigurable metasurface. The unit cell of the device consists of two split-ring resonators embedded with a V O 2 ribbon. By electrically triggering the insulator-to-metal transition of V O 2 , the resonance mode and resonance intensity of the unit cell can be dynamically controlled. The simulation results show that the structure can achieve a phase shift of about 360° in the range of 1.03-1.13 THz, and the reflection amplitude can reach 80%. The device has potential applications in THz imaging, radar, broadband wireless communications, and array phase control.

Background: Temporin is one family of the shortest antimicrobial peptides found in Ranidae frogs. Staphylococcus aureus is one of the main pathogens of suppurative diseases and food contamination, causing severe local or systemic infections in humans. Temporin-GHa (GHa) was previously obtained from Hylarana guentheri, showing weak antibacterial activity against S. aureus. Most temporin peptides are positively charged by arginine and lysine; however, GHa contains histidine., Objective: In order to investigate the impact of positively charged amino acid on its antibacterial and antibiofilm activity, GHa4R was designed and synthesized by replacing histidine with arginine in GHa., Methods: The antibacterial activity and efficacy against S. aureus were detected by minimum inhibitory concentration, minimum bactericidal concentration, and time-killing kinetics assays. The action mechanism was determined by propidium iodide uptake and scanning electron microscopy assays. The antibiofilm activity was measured by the MTT method. Eradication of biofilm was observed by fluorescence microscope., Results: Compared to GHa, GHa4R had stronger antibacterial activity and bactericidal efficacy against S. aureus. Impressively, GHa4R presented antibacterial activity against methicillin-resistant S. aureus (MRSA). It was barely affected by temperature, pH, and storage period, showing high stability. Furthermore, it increased the permeability of the cell membrane and damaged the membrane integrity, leading to cell death. In addition, GHa4R did not induce antibiotic resistance in S. aureus in 30 days, but the MIC of vancomycin was doubled. It not only inhibited S. aureus biofilm formation but also eradicated 24 h-biofilms., Conclusion: The above-mentioned characteristics make GHa4R a promising candidate for the treatment of S. aureus infections., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

BACKGROUND This study compared the effects of peritoneal dialysis and hemodialysis on cognitive dysfunction and health-related quality of life (HRQOL) in end-stage renal disease (ESRD) patients and analyzed other potential influencing factors. MATERIAL AND METHODS A total of 265 patients who received dialysis at our hospital were included and divided into the hemodialysis group (n=115) and the peritoneal dialysis group (n=150). The cognitive performance was assessed by the Beijing version of the Montreal Cognitive Assessment. The Kidney Disease Quality of 36-Item Short Form Survey and a kidney disease-related quality of life assessment were used for evaluating HRQOL. Univariate and multivariate linear regression analyses were used to explore the effects of dialysis on cognitive dysfunction and HRQOL. RESULTS As compared with the hemodialysis group, the peritoneal dialysis group had lower scores on the Montreal Cognitive Assessment (ß=-8.35, 95% CI: -9.85 to -6.86), 36-Item Short Form Survey (ß=-10.20, 95% CI: -11.94 to -8.45), and kidney disease-related quality of life assessment (ß=-8.67, 95% CI: -10.10 to -7.23). After adjustment for sex, age, BMI, marital status, educational level, income level, presence of diabetes, duration of kidney disease, duration of dialysis, and dialysis frequency, the results were consistent with that of the crude model. CONCLUSIONS In the present study, patients receiving peritoneal dialysis had worse cognitive dysfunction and worse HRQOL compared to patients receiving hemodialysis, which might lead to poorer outcomes of ESRD patients. The related factors affecting cognitive dysfunction and HRQOL were also explored, which could help clinicians to determine the optimal treatment for ESRD patients.

One of the ways in which plants can respond to temperature is via alternative splicing (AS). Previous work showed that temperature changes affected the splicing of several circadian clock gene transcripts. Here, we investigated the role of RNA-binding splicing factors (SFs) in temperature-sensitive AS of the clock gene LATE ELONGATED HYPOCOTYL (LHY). We characterized, in wild type plants, temperature-associated isoform switching and expression patterns for SF transcripts from a high-resolution temperature and time series RNA-seq experiment. In addition, we employed quantitative RT-PCR of SF mutant plants to explore the role of the SFs in cooling-associated AS of LHY. We show that the splicing and expression of several SFs responds sufficiently, rapidly, and sensitively to temperature changes to contribute to the splicing of the 5'UTR of LHY. Moreover, the choice of splice site in LHY was altered in some SF mutants. The splicing of the 5'UTR region of LHY has characteristics of a molecular thermostat, where the ratio of transcript isoforms is sensitive to temperature changes as modest as 2 °C and is scalable over a wide dynamic range of temperature. Our work provides novel insight into SF-mediated coupling of the perception of temperature to post-transcriptional regulation of the clock., (© 2018 The Authors. Plant, Cell & Environment Published by John Wiley & Sons Ltd.)