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This article proposes an improved model-free deadbeat predictive current control (MFCC) method for permanent magnet synchronous motors (PMSMs) based on the ultralocal model and H∞ norm. Firstly, the traditional deadbeat predictive current control (DPCC) method is introduced and a theoretical analysis is conducted on its sensitivity to parameters. Building upon this, the limitations of model dependence and the limited robustness of the deadbeat predictive current control method based on the extended state observer (ESO-DPCC) are theoretically analyzed. Furthermore, an improved MFCC method based on the ultralocal model is proposed, and the influence of the observer on MFCC is theoretically analyzed. This study combined the proposed method with the H∞ norm, and the optimal coefficients of the observer were tuned to enhance the robustness and dynamic performance of the current loop. Finally, the proposed algorithms were validated on a 400 W PMSM platform. [ABSTRACT FROM AUTHOR]

To meet the environmental protection and flame retardancy requirements for epoxy resins (EPs) in certain fields, in this study, a novel triazine-ring-containing DOPO-derived compound (VDPD), derived from vanillin, 2,4-Diamino-6-phenyl-1,3,5-triazine, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), was synthesized using a one-pot method. Flame-retardant epoxy resin (FREP) was prepared by adding various ratios of VDPD to EP and curing with 4,4-diaminodiphenylmethane (DDM). The curing behavior, thermal stability, mechanical properties, and flame-retardant properties of the FREP were examined in various tests. According to the results, when the amount of VDPD added to the EP increased, the glass transition temperature of the FREP decreased linearly, and the flame-retardant properties gradually improved. With a 0.4 wt.% P content, the vertical burning rating of EP/DDM/VDPD-0.4 (according to the theoretical content of VDPD) reached the V-0 level, and the LOI value reached 33.1%. In addition, the results of a CCT showed that the peak heat release rate (PHRR) of EP/DDM/VDPD-0.4 decreased by 32% in comparison with that of the EP. Furthermore, compared with those of the EP, the tensile strength of EP/DDM/VDPD-0.4 decreased from 80.2 MPa to 74.3 MPa, only decreasing by 6 MPa, and the tensile modulus increased. Overall, VDPD can maintain the mechanical properties of EP and effectively improve its flame-retardant properties. [ABSTRACT FROM AUTHOR]

The genus Rosa is globally popular with well-established applications since it has a high edible and medicinal value. However, relatively limited research has been conducted on the composition and quality of wild Rosa fruits. The present study aimed to compare the properties and chemical components of five wild edible Rosa fruits, Rosa roxburghii, Rosa sterilis, Rosa laevigata, Rosa davurica, and Rosa sericea. The UPLC-ESI-MS/MS approach identified the key metabolites among the five Rosa fruits as flavonoids, phenolic acids, and organic acids. The main differential metabolites among the five fruits are flavonoids (22.29–45.13%), phenolic acids (17–22.27%), and terpenoids (7.7–24%), respectively. In total, 125 compounds served as potential markers for the five Rosa species. Differential metabolic pathways of five Rosa fruits were analyzed using the KEGG approach. Rosa laevigata fruits showed the highest total polysaccharide (TPS) content of 64.48 g/100 g. All the five Rosa extracts effectively decreased the levels of malondialdehyde while increasing the activities of superoxide dismutase and glutathione peroxidase in the H2O2-induced HaCaT cell model, demonstrating high potential for antioxidant development. Our findings suggest that the five studied Rosa fruits exhibit biological activity and edible value worth further exploration. [ABSTRACT FROM AUTHOR]

Background: To establish a fast and simple quantitative method for detection of heart-type fatty acid-binding protein (H-FABP) in serum based on a background fluorescence quenching im munochromatographic assay. Methods: A detection card based on the double-antibody sandwich double-antibody method with background fluorescence quenching was developed for quantitative m easurement of H-FABP in serum. The optimal concentrations of control for coating the test and control lines were determined as well as the concentrations of gold-labeled antibodies used in preparing the detection system. The detection method for H-FABP in serum was established and validated using real-world clinical samples. Results: The optimal concentrations of labeling antibody and coating antibody were 5.0 mg/mL and 1.0 mg/m L, respectively. The test card had a sensitivity of 1.15 ng/m L over a linear concentration range of 0-100 ng/m L. Based on three batches prepared for testing the card, the relative standard deviation (RSD) within batches was less than 15% without a significant difference (P = 0.942 ). The detection method was tested against common interfering substances in serum, such as bilirubin, triglyceride and serum anticoagulants ethylenediamine tetraacetic acid (EDTA), heparin, and sodium citrate, and no significant cross-reaction was detected. The test method was further validated with 50 clinical serum samples, and the test results were COM parable with standard reference detection methods with good correlation (R = 0.95 ). Conclusion: O ur study presents a new method with strong specificity and sensitivity for the detection of H-FABP in serum, which could promote H-FABP detection in a broad range of applications.

The conflict between rice production and water scarcity is becoming more pronounced. Therefore, the advancement of water‐saving rice cultivation is crucial in guaranteeing both food and ecological security. This study provides a summary of the development and characteristics of various water‐saving cultivation techniques for rice, including alternate wetting and drying irrigation, wet irrigation, controlled irrigation, the system of rice intensification, direct seeding rice, and dry cultivation of rice (DCR). We also introduce the varietal characteristics of upland rice, aerobic rice, water‐saving and drought‐resistant rice, and DCR. We summarize the impact of different water‐saving cultivation models on yield and quality and regulatory measures, and propose challenges and strategies for the development of water‐saving cultivation of rice in the future. We hope to provide a reference for promoting the development of rice water‐saving cultivation and dry farming agriculture. Core Ideas: This review summarizes the development of water‐saving cultivation techniques for rice.This review presents the challenges and strategies for developing water‐saving rice cultivation.This review provides technical and theoretical support for the development of rice water‐saving cultivation. [ABSTRACT FROM AUTHOR]

Zanthoxylum motuoense Huang, native to Tibet, China, is a newly discovered Chinese prickly ash, which, recently, has increasingly attracted the attention of researchers. In order to understand its volatile oil compositions and flavor characteristics, and to explore the flavor difference between Z. motuoense and the common Chinese prickly ash sold in the market, we analyzed the essential oils of Z. motuoense pericarp (MEO) using HS-SPME/GC×GC-TOFMS coupled with multivariate data and flavoromics analyses. The common commercial Chinese prickly ash in Asia, Zanthoxylum bungeanum (BEO), was used as a reference. A total of 212 aroma compounds from the 2 species were identified, among which alcohols, terpenoids, esters, aldehydes, and ketones were the major compounds. The predominant components detected from MEO were citronellal, (+)-citronellal, and β-phellandrene. Six components—citronellal, (E,Z)-3,6-nonadien-1-ol, allyl methallyl ether, isopulegol, 3,7-dimethyl-6-octen-1-ol acetate, and 3,7-dimethyl-(R)-6-octen-1-ol—could be used as the potential biomarkers of MEO. The flavoromics analysis showed that MEO and BEO were significantly different in aroma note types. Furthermore, the content differences of several numb taste components in two kinds of prickly ash were quantitatively analyzed using RP-HPLC. The antimicrobial activities of MEO and BEO against four bacterial strains and nine plant pathogenic fungi were determined in vitro. The results indicated that MEO had significantly higher inhibitory activities against most microbial strains than BEO. This study has revealed the fundamental data in respect of the volatile compound properties and antimicrobial activity of Z. motuoense, offering basic information on valuable natural sources that can be utilized in the condiment, perfume, and antimicrobial sectors. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Metal organic frameworks have been employed as high‐performance layered double hydroxide (LDH) composite supercapacitor electrode materials but have shown unsatisfactory redox ability and stability. Herein, a host‐guest CuMo‐based polyoxometalate‐based metal organic framework (POMOF) with copious electrochemically active sites and strong electrochemical redox activities has been effectively coupled with POM‐incorporated CoNi‐LDH to develop a nanocomposite (NENU‐5@CoNi‐LDH) by a simple solvothermal method. The designed electrode shows a high specific capacity of 333.61 mAh·g–1 at 1 A·g–1. In addition, the novel hybrid symmetric supercapacitor NENU‐5@CoNi‐LDH/active carbon (AC) demonstrated a high energy density of 80.8 Wh·kg–1 at a power density of 750.7 W·kg–1. Interestingly, the nanocomposite of NENU‐5@CoNi‐LDH exhibits an outstanding capacitance retention of 79% after 5000 charge‐discharge cycles at 10 A·g–1. This work provides a new strategy and will be the backbone for future energy storage research. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Metal organic frameworks have been employed as high‐performance layered double hydroxide (LDH) composite supercapacitor electrode materials but have shown unsatisfactory redox ability and stability. Herein, a host‐guest CuMo‐based polyoxometalate‐based metal organic framework (POMOF) with copious electrochemically active sites and strong electrochemical redox activities has been effectively coupled with POM‐incorporated CoNi‐LDH to develop a nanocomposite (NENU‐5@CoNi‐LDH) by a simple solvothermal method. The designed electrode shows a high specific capacity of 333.61 mAh·g–1 at 1 A·g–1. In addition, the novel hybrid symmetric supercapacitor NENU‐5@CoNi‐LDH/active carbon (AC) demonstrated a high energy density of 80.8 Wh·kg–1 at a power density of 750.7 W·kg–1. Interestingly, the nanocomposite of NENU‐5@CoNi‐LDH exhibits an outstanding capacitance retention of 79% after 5000 charge‐discharge cycles at 10 A·g–1. This work provides a new strategy and will be the backbone for future energy storage research. [ABSTRACT FROM AUTHOR]

The adaptive filters (ANF) have been commonly used in current harmonic suppression. However, the digital delay will narrow the stability region and its harmonic suppression performance will be deteriorated at high-speed region. To overcome this problem, this paper proposed two modified ANF. Combining with the deadbeat current (DBC) controller, the effect of digital delay on ANF is analyzed. A simple one step harmonic prediction method (OSPANF) is proposed to replace the traditional steepest gradient method (SGM). Based on the OSPANF, the current can be controlled stably in the high-speed area and the harmonic suppression effect is better than the traditional notch filter. Through bode diagram analysis, OSPANF will have a harmonic amplification peak near the set notch frequency, which may bring additional disturbances. Thus, a two steps prediction adaptive notch filter (TSPANF) is implemented. Through the Experimental results, it can be proved that the proposed TSPANF method has better harmonic suppression effect in the high-speed area than OSPANF and the stability region of the proposed two methods is larger than the traditional method. [ABSTRACT FROM AUTHOR]

This article proposes a pseudo-random high-frequency triangular-wave current signal injection (PR-HFTCI) based sensorless control scheme for synchronous reluctance motor (SynRM) drives at zero-low speed domain to suppress the high-frequency (HF) loss and the HF audible noise which are introduced by the significant nonlinearities of SynRMs and the traditional constant amplitude HF square-wave voltage injection method. The pseudo-random HF triangular-wave current signal with random frequency and random phase is injected to eliminate the discrete spectrum of the current power spectra density (PSD) and the corresponding current PSD analysis is performed to evaluate it. In addition, the HF component amplitude of the d-axis voltage reference can be adjusted adaptively with the variation of load to maintain the HF current amplitude constant, it is easy to implement and does not require any extra regulator and signal processing. Hence, the HF loss and the HF torque ripple can be effectively reduced under the heavy load. Finally, the effectiveness and the correctness of the proposed PR-HFTCI based sensorless control scheme are validated with experiments on a 1.5-kW SynRM drive platform. [ABSTRACT FROM AUTHOR]

Phytochemical studies led to the isolation of five new sesquiterpeniod esters, named balsamiferine N-R, along with ten known compounds (6-15) from the leaves of Blumea balsamifera (L.) DC. The skeletons of nine known sesquiterpeniods belong to guaiane and eudesmane. The structures of the new compounds including their absolute configurations were elucidated by comprehensive spectroscopic analysis, and quantum-chemical electronic circular dichroism (ECD) calculation. Compounds 3 and 4 showed significant inhibitory effects on influenza A virus (H3N2) with IC50 values of 46.23 μg/mL and 38.49 μg/mL, respectively. It was the first report on the anti-influenza A virus constituents from B. balsamifera. [ABSTRACT FROM AUTHOR]

This study proposes a sensorless flux adaption direct torque and flux control (DTFC) for an interior permanent magnet synchronous motor (IPMSM), in which an maximum torque per ampere (MTPA) based on active flux and an adaptive second-order sliding mode observer (SOSMO) are adopted. Flux adaption DTFC is proposed based on the existing active flux concept. Thus, the stator current amplitude can be minimised in both steady state and transient state. Furthermore, to realise the sensorless control of the IPMSM, an adaptive SOSMO is proposed. Compared with constant gains SOSMO, the gains of the adaptive SOSMO can be adjusted adaptively with the motor speed changing. Then, the precision of position estimation is enhanced effectively in a wide speed range. Numerical simulations and experiments with a 60 kW IPMSM are implemented. In addition, the results validate the capability of the proposed sensorless flux adaption DTFC scheme. [ABSTRACT FROM AUTHOR]

In this study, the permanent-magnet synchronous motor sensorless control systems realised by sliding-mode observers in stationary aß and estimated γδ coordinates are systematically studied and compared. First, based on the sufficient condition of sliding-mode stability, a more reasonable selection method of boundary layer width and sliding-mode gain is derived, effectively reducing the system chattering. Furthermore, in extracting estimated extended electromotive force, the advantages and disadvantages of the backforward method in the aß-axis and the influence of filter cut-off frequency on estimation error in the γδ-axis are analysed. Finally, the estimation error, speed range, stability, and the effect of speed error of these two sensorless control systems are analysed and compared. The results indicate that these two systems have equivalent position error above a certain speed, and the γδ-axis estimation system has a larger position error in low-speed range, but still operating well. Moreover, the γδ-axis estimation algorithm has better stability and wider-speed range. Owing to the fast track of phase-locked loop, the effect of speed error on estimation accuracy of the γδ-axis system can be neglected. Simulation and experiment verified the theoretical analysis and comparison. [ABSTRACT FROM AUTHOR]

It is recognized that cystatin C is an effective marker for monitoring the glomerular filtration rate and the clinical diagnosis of various diseases. In this study, a novel immunochromatographic method has been established to achieve quantitative detection of serum cystatin C. Unlike conventional and traditional gold immune chromatographic assays (GICAs), a uniform layer of a fluorescent film was added to the solid phase, which has been designated as the background fluorescence quenching immune chromatographic assay (bFQICA). Under the optimized conditions, there was a good correlation between the fluorescence signal ratio (F1/F2) of the background fluorescence (F1) to the fluorescence signal at the detection line (F2) for cystatin C at concentrations from 0.0 ng/mL to 100 ng/mL with a correlation coefficient of 0.9977. The detection limit was 0.69 ng/mL, and the recovery values were 87.9–105%. The differences between the intra- and interbatch precision were less than 15% in three batches. In addition, after 120 serum samples were detected, there were no significant differences in the results obtained by bFQICA and immunoturbidimetry (t = 0.963, p = 0.338 > 0.05). This work demonstrates that bFQICA is a simple, sensitive, and accurate approach for the determination of serum cystatin C, providing a new approach for the clinical diagnosis of cystatin C. [ABSTRACT FROM AUTHOR]

Surface erosion of wind turbine blades, which are a key component of wind turbines, plays an important role in reducing the output power and service life of the blades. Rain erosion is also detrimental to wind turbine blades. In this review, the research progress on rain erosion is analyzed from the aspects of protection technology, rain erosion mechanism and related rain erosion tests and simulations. A comprehensive protective coating can be obtained by modifying or combining resins with different properties. Investigation of the rain erosion mechanism should consider the influence of the acidity of rain on the organic coatings. The rain erosion device should be more in line with the natural environment, and the dual structure of the substrate composite and surface coating of the blades should be fully considered as well in the rain erosion simulation. [ABSTRACT FROM AUTHOR]

A novel intumescent flame retardant (IFR) system composed of ammonium polyphosphate and poly (1,3-diaminopropane-1,3,5-triazine-o-bicyclic pentaerythritol phosphate) (APP/PDTBP) was mixed with polyethylene to prepare the continuous glass fibre reinforced polyethylene (CGF/PE) unidirectional prepregs by melt impregnation process, and then the CGF/PE/IFR composite laminate were consolidated by hot compression moulding method. The flame retardancy, thermal stability and mechanical properties of CGF/PE/IFR composite laminates were investigated by limiting oxygen index, vertical burning test, cone calorimetric test, thermogravimetric analysis, tensile and flexural strength tests, mode I interlaminar fracture toughness test, and scanning electron microscopy (SEM). The flame retardancy of CGF/PE composite laminates increased with the increase of IFR system loading, which attributes to the formation of intumescent char layer from flame retardants and the weakening of wicking actions of glass fibres. The mechanical properties increased and then decreased with addition of flame retardants, except for the flexural strength with continuous increase. The SEM images showed that IFR system had toughening effect and could improved the strength of fibre-matrix interface. Based on the mechanical properties and the flame retardancy, when the matrix contains 30 wt% IFR system, the CGF/PE/IFR composite laminate had the best comprehensive performance. Image 1 [ABSTRACT FROM AUTHOR]

The scheme based on direct torque and flux control (DTFC) as well as active flux is a good choice for the interior permanent magnet synchronous motor (IPMSM) sensorless control. The precision of the stator flux observation is essential for this scheme. However, the performance of traditional observers like pure integrator and the low-pass filter (LPF) is severely deteriorated by disturbances, especially dc offset. Recently, a sliding-mode stator flux observer (SMFO) was proposed to reduce the dc offset in the estimated stator flux. However, it cannot eliminate the dc offset totally and will cause the chattering problem. To solve these problems, a novel super-twisting sliding-mode stator flux observer (STSMFO) is proposed in this paper. Compared with SMFO, STSMFO can reduce the chattering and fully eliminate the dc offset without any amplitude and phase compensation. Then, the precision of the stator flux and rotor position can be greatly improved over a wide speed region. The detailed mathematical analysis has been given for comparing it with another three traditional observers. The numerical simulations and experimental testing with an IPMSM drive platform have been implemented to verify the capability of the proposed sensorless scheme. [ABSTRACT FROM AUTHOR]

In this work, a novel phosphorous–nitrogen based charring agent named poly(1,3-diaminopropane-1,3,5-triazine-o-bicyclic pentaerythritol phosphate) (PDTBP) was synthesized and used to improve the flame retardancy of high-density polyethylene (HDPE) together with ammonium polyphosphate (APP). The results of Fourier transform infrared spectroscopy (FTIR) and 13C solid-state nuclear magnetic resonance (NMR) showed that PDTBP was successfully synthesized. Compared with the traditional intumescent flame retardant (IFR) system contained APP and pentaerythritol (PER), the novel IFR system (APP/PDTBP, weight ratio of 2:1) could significantly promote the flame retardancy, water resistance, and thermal stability of HDPE. The HDPE/APP/PDTBP composites (PE3) could achieve a UL-94 V-0 rating with LOI value of 30.8%, and had a lower migration percentage (2.2%). However, the HDPE/APP/PER composites (PE5) had the highest migration percentage (4.7%), lower LOI value of 23.9%, and could only achieve a UL-94 V-1 rating. Besides, the peak of heat release rate (PHRR), total heat release (THR), and fire hazard value of PE3 were markedly decreased compared to PE5. PE3 had higher tensile strength and flexural strength of 16.27 ± 0.42 MPa and 32.03 ± 0.59 MPa, respectively. Furthermore, the possible flame-retardant mechanism of the APP/PDTBP IFR system indicated that compact and continuous intumescent char layer would be formed during burning, thus inhibiting the degradation of substrate material and improving the thermal stability of HDPE. [ABSTRACT FROM AUTHOR]

First-principles calculations based on density functional theory (DFT) have been carried out to investigate the effects of crystal defects (intrinsic vacancy defects and ion doping) on the microwave dielectric response and the correlative electromagnetic properties of α-MnO2 systematically. The possible role of crystal defects in electromagnetic performance is studied utilizing density of states (DOS) and the bond length between the manganese and oxygen. Lattice distortion is induced by the introduction of crystal defects. The spin-electronic DOS demonstrates that Ni doping enhances the spin-polarization of MnO2, which indicates that the Ni-doped MnO2 possesses certain magnetic characteristic, which is helpful for magnetic loss. The emergence of a new defect mode, contributes to the relaxation polarization phenomenon, so as to enhance the dielectric loss ability. In addition, through the change of the bond length and pseudo gap width, it can be learned that the bond strength and covalency of Mn-O bonds are weakened, which increases the dielectric loss of MnO2. The results throw light on the exploration of theoretical research on the microwave absorbing properties of MnO2 with crystal defects. [ABSTRACT FROM AUTHOR]

Background: The purpose of this research is to summarize the academic expertise of Professor Lu Zhizheng in the treatment of Chronic Atrophic Gastritis, and to explain his clinical reasoning and common prescriptions in the treatment of CAG., Methods: Professor Lu's outpatient cases of CAG from January 2008 to December 2021 were selected, and the PageRank algorithm was applied on the FangNet platform to analyze the usage frequencies of herbs, their four natures and five flavors according to Traditional Chinese Medicine, core herbs, and herb clustering patterns, with the goal of summarizing the distinguishing features of Professor Lu's academic and clinical approach to CAG. A total of 170 patients from 252 consultations were included in this study. The prescriptions involved a total of 239 herbs, which occurred a cumulative 4339 times. The herb natures were mainly warm, neutral, and slightly cold, and the herb flavors were predominantly sweet, bitter, and pungent. The channel tropism of the selected herbs primarily targeted the spleen, stomach, and lung meridians. Herb rank analysis showed that 34 herbs, including Gancao, Taizishen, Banxia, Huanglian, Shengjiang, Baizhu, Yiyiren, Maiya, Cangzhu, and Kuxingren, were the driver herbs used by Professor Lu for the treatment of CAG., Results: Herb-herb co-occurrence/exclusivity analysis revealed 10 sets of frequently used herb pairs; herb cluster analysis yielded 10 herb clusters. These results reflected the emphasis Professor Lu placed on protecting Qi and Yin while clearing damp-heat. Professor Lu Zhizheng utilized dialectics reinforced with flexible thinking in the treatment of CAG, and emphasized that identifying the pathogenesis and addressing the syndrome should be prioritized., Conclusions: The characteristic treatment strategy aimed to replenish Qi and nourish Yin, clear away damp-heat, and treat CAG patients comprehensively under the guidance of established principles.

What Is Already Known on This Topic?: There is a lack of comprehensive data on the coverage of the human papillomavirus (HPV) vaccine in China. The limited published literature hampers our ability to accurately assess the current situation., What Is Added by This Report?: This study aimed to determine the rates of HPV vaccine coverage based on data from the electronic vaccination registry reported to the China Immunization Information System between 2017 and 2022. While there was an increase in HPV vaccine coverage each year, the overall coverage remained below the optimal level., What Are the Implications for Public Health Practice?: This study presents evidence of low HPV vaccine coverage when administered outside of a national immunization program. Therefore, it is recommended that the HPV vaccine be included in the National Immunization Program in order to meet the 2030 WHO target of achieving 90% vaccination coverage for girls by the age of 15., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2024.)