Search

In this article, a disturbance estimation–based robust generalized predictive control approach is proposed for angle demand control of a steer-by-wire system. It consists of a generalized predictive controller and a nonlinear disturbance observer. First, the nonlinear disturbance observer is used to estimate the effects of the lumped disturbances, including model uncertainties, unmodeled dynamics, and external disturbances. Second, the estimate of the nonlinear disturbance observer is integrated into the generalized predictive controller design for front-wheel angle output prediction. Then, an explicit analytical form of the disturbance estimation–based robust generalized predictive controller is derived. In addition, rigorous stability analysis proves that the closed-loop system under the proposed control is stable. Finally, the developed control approach has been downloaded into a steering control unit and tested in real-world conditions using a vehicle test bench to fully realize steering by wire in engineering practice. Extensive simulations and experiments have been performed, and results show that the proposed control approach outperforms the comparative controllers regarding disturbance rejection, robust tracking performance under model uncertainties, and disturbances.

With the rapid advancement of emerging technologies, an increasing number of studies are integrating technology into teacher professional development. This evolving trend, however, presents additional challenges for educators, particularly in the form of heightened technostress. Despite this, there is a noticeable gap in research investigating the factors influencing teacher technostress and their interrelationships with technology-supported teacher learning (TSTL). This study aims to scrutinize factors influencing teachers’ technostress and satisfaction in TSTL, grounded in the person–environment fit theory. Data were collected from 681 K-12 teachers in China. The results from structural equation modelling revealed that, within TSTL, teachers’ value beliefs and school support significantly impact both technostress and satisfaction. Intriguingly, technostress itself did not demonstrate a direct relationship with satisfaction. Subsequent multi-group assessments shed light on distinct correlations between teachers’ value beliefs, school support, and technostress based on gender and teaching levels in TSTL. In light of the study’s insightful findings, several recommendations are proposed for the future implementation of TSTL.

Various additives have been introduced to assist in film preparation and defect passivation. Herein, fluoroiodobenzene (FIB) molecules with different numbers of F atoms were incorporated into perovskite films to optimize the film quality as well as passivate defects. Based on the calculation and experimental results, it was found that the FIB additives were inclined to exist at the bottom of the film because of the strong affinity between F atoms stemming from FIB molecules and O atoms stemming from TiO2, especially for molecules with more F atoms. By optimization of the FIB molecule, the perovskite film crystallinity was significantly improved, the carrier lifetimes were prolonged, and the charge extraction ability was also enhanced. The device with FIB with one F atom achieved a photoelectrical conversion efficiency as high as 22.89% with a Vocof 1.118 V, fill factor (FF) of 80.44%, and Jscof 25.45 mA cm–2, which was much higher than that of the control device with an efficiency of 20.87%. Furthermore, FIB molecules with three and five F atoms also achieved higher efficiency than that of the control device. The devices with FIB molecules showed better stability than the devices without additives. The unencapsulated devices with FIB additives held 90% of their original efficiencies in an ambient environment with a temperature of 15–25 °C and a relative humidity of 20–30%, while the control device dropped to 76% after more than 1000 h.

Introduction: Pharmacist-driven (PD) dosing and monitoring services have been shown to improve the clinical and economic outcomes in patients treated with different antibiotics, other than teicoplanin. This study investigates the impact of PD dosing and monitoring services on the clinical and economic outcomes of non-critically ill patients receiving teicoplanin treatment. Methods: A single-center retrospective study was conducted. Patients were divided into the PD group and the non-PD (NPD) group. Primary outcomes included the achievement of target serum concentration, and a composite endpoint of all-cause mortality, intensive care unit (ICU) admission, and sepsis or septic shock development during hospitalization or within 30 days of hospital admission. The cost of teicoplanin, overall medication cost, and total cost during hospital stay were also compared. Results: A total of 163 patients from January to December 2019 were included and assessed. Seventy patients were assigned to the PD group and 93 to the NPD group. The PD group had a higher percentage of patients reaching the target trough concentration (54% versus 16%, p< 0.001). Around 26% of the patients in the PD group and 50% of the patients in the NPD group met the composite endpoint during their hospital stay (p= 0.002). The PD group exhibited a significantly lower incidence of sepsis or septic shock, shorter hospital stays, reduced drug costs, and lower total expenses. Conclusions: Our study demonstrates that pharmacist-driven teicoplanin therapy can improve the clinical and economic outcomes for non-critically ill patients.

In contemporary cities, road collapse is one of the most common disasters. This study proposed a framework for assessing the risk of urban road collapse. The framework first established a risk indicator system that combined environmental and anthropogenic factors, such as soil type, pipeline, and construction, as well as other indicators. Second, an oversampling technique was used to create the dataset. The framework then constructed and trained a convolutional neural network (CNN)-based model for risk assessment. The experimental results show that the CNN model (accuracy: 0.97, average recall: 0.91) outperformed other models. The indicator contribution analysis revealed that the distance between the road and the construction site (contribution: 0.132) and the size of the construction (contribution: 0.144) are the most significant factors contributing to road collapse. According to the natural breaks, a road collapse risk map of Foshan City, Guangdong Province, was created, and the risk level was divided into five categories. Nearly 3% of the roads in the study area are at very high risk, and 6% are at high risk levels, with the high risk roads concentrated in the east and southeast. The risk map produced by this study can be utilized by local authorities and policymakers to help maintain road safety.

A natural hazard-related disaster event often causes a series of secondary disasters, forming a disaster chain. Modeling the evolution of disaster chains in multi-hazard scenarios is crucial for risk governance and urban resilience. However, existing multi-hazard models are limited by complex model design and fixed disaster types, making it impossible to ensure flexible reactions to complex and diverse scenarios. This study presents a disaster management system for disaster model service chain (DMSC) to implement interoperable multi-hazard modeling. To achieve efficient model interaction in the DMSC, a management module is designed to normalize heterogeneous single-hazard models based on disaster system theory and the Open Geospatial Consortium standards, enabling them to be accessible, reusable, and interoperable. The normalized models are then adaptively orchestrated through an orchestration module to establish optimal executable DMSCs for different multi-hazard scenarios. Taking an earthquake disaster chain as a case study, we demonstrate that the disaster management system shows stable and flexible performance for multi-hazard modeling.

In recent years, DC micro-grid has attracted widespread attention due to the significant increase in DC loads and the demand for high-quality power. This paper proposes a novel primary double winding coupling topology of the DC transformer (DCT) for DC micro-grid applications. The primary side high-frequency full-bridge inverter is replaced by a novel topology without shoot-through problem. As a result, the reliability of the system is improved, and dead-time is unnecessary to be added to the driving signals thus the dc voltage utilization is higher. Compared to the no dead-time dual-buck inverter, the proposed topology has more advantages in the size and cost, because the primary two windings can be integrated on the same core. What’s more, the influence of the leakage inductance can be decreased by the parallel effect, so that the transmission efficiency of the DCT can be improved. In this paper, the evolution process of the non-dead zone and comparison with other topologies are given. The equivalent circuit and the compensation design are described in detail. The working principle and efficiency of the proposed topology are analysed and calculated. The simulation and a simple prototype were built up for the experimental tests to verify the advancement of the proposed DCT.

Technology integration refers to the process of innovation diffusion, from understanding technology knowledge to achieving a high level quality of technology usage. To address the gap in research regarding the critical factors that influence K-12 teachers’ practice of technology integration at the initial stage of a massive government-led training programme in rural areas, this study sought to explore the comprehensive effects of teachers’ technological pedagogical content knowledge (TPACK) and beliefs on their technology integration. Participants included 267 in-service K-12 teachers from four pilot schools in a remote rural area in north-western China. We found that: (a) T-related knowledge positively predicted the teachers’ technology integration quality and quantity, while T-unrelated knowledge negatively influenced technology integration quality and quantity; (b) the positive valence of teachers’ beliefs (PVTBs) was positively related to technology integration quality, the negative valence of teachers’ beliefs was negatively related to technology integration quantity; (c) the PVTBs impacted the quality and quantity of technology integration through T-related knowledge; and (d) gender significantly moderated the impact of positive beliefs and T-related knowledge on technology integration. This study suggests that improving K-12 teachers’ technology integration in rural areas requires prioritizing professional development programmes that improve teachers’ beliefs in the initial stage of technology diffusion.

In the control of three-phase system, AC signals are always changed into DC signals by synchronous coordinate transformation. A decoupling control scheme in the dq synchronous reference frame (SRF) is proposed to realize active and reactive current decoupling of three-phase inverter. The complex vector control model is established in SRF. Different from the model established in static reference frame, the SRF control model can reflect the coupling characteristic of the active and reactive current. As a result, the PI controller with complex coefficient can be applied to realize current decoupling. In this paper, the coupling characteristic of three-phase system is analyzed. A novel complex PI controller design method is proposed based on the SRF control model and the coefficients are calculated. And its implementation in the control loop is given. Compared with existing PI controllers with real or complex coefficients, the proposed complex PI controller can realize completely the decoupling of the active and reactive current in three-phase system. Besides, the control scheme can make current loop fulfill the expected symmetrical bandwidth, so as to realize a higher effective set-off frequency. As a result, the inverter can achieve well dynamic performance. Finally, the simulation and experimental results are given to verify the theoretical analysis.

ABSTRACTA growing body of evidence suggests the pivotal role of long non-coding RNA (lncRNA) in influenza virus infection. Based on next-generation sequencing, we previously demonstrated that Lnc45 was distinctively stimulated by H5N1 influenza virus in mice. In this study, we systematically investigated the specific role of Lnc45 during influenza A virus (IAV) infection. Through qRT-PCR, we first demonstrated that Lnc45 is highly up-regulated by different subtypes of IAV strains, including H5N1, H7N9, and H1N1 viruses. Using RNA-FISH and qRT-PCR, we then found that Lnc45 can translocate from nuclear to cytoplasm during H5N1 virus infection. In addition, forced Lnc45 expression dramatically impeded viral replication of H1N1, H5N1, and H7N9 virus, while abolish of Lnc45 expression by RNA interference favored replication of these viruses, highlighting the potential broad antiviral activity of Lnc45 to IAV. Correspondingly, overexpression of Lnc45 inhibited viral polymerase activity and suppressed IAV-induced cell apoptosis. Moreover, Lnc45 significantly restrained nuclear aggregation of viral NP and PA proteins during H5N1 virus infection. Further functional study revealed that the stem ring arms of Lnc45 mainly mediated the antiviral effect. Therefore, we here demonstrated that Lnc45 functions as a broad-spectrum antiviral factor to inhibit influenza virus replication probably through inhibiting polymerase activity and NP and PA nuclear accumulation via its stem ring arms. Our study not only advances our understanding of the complexity of the IAV pathogenesis but also lays the foundation for developing novel anti-IAV therapeutics targeting the host lncRNA.

This paper proposed a DC bus voltage stabilization control strategy of the full-quadrant operated three-phase grid-connected inverter, of which the reactive current is not 0. The strategy considers the power loss of the switches caused by both active and reactive current, which would affect the dynamic performance of voltage loop. In this condition, the power loss can be seen as a disturbance of the voltage loop so it should be taken into consideration in the design process. Besides, the voltage loop is the outer loop of the active current loop. The active and reactive current are coupled because of the coordinate transformation. As a result, the interference of the reactive current would affect the DC bus voltage through current coupling. The proposed control strategy considers the power loss and designs the outer voltage loop. Also the decoupling current controller based on complex vectors is discussed. With the proposed DC bus voltage stabilization strategy, the inverter can realize good dynamic and static performances. The control principle is analyzed in detail. The design of the control loops are discussed. The influences of the reactive current on the DC voltage and active current are analyzed. Finally, the simulation and experimental results verify the theoretical analysis.

This paper proposes a complex PI current controller design method of three-phase inverter based on multiple equations construction. The mathematical model of three-phase inverter system plays an important role in the controller design process. In the synchronous reference frame, the inverter model introduces coupling elements, which is different from the model in the stationary reference frame and brings difficulty for current controller design. Complex vector model (CVM) is introduced in the current loop, which is established in the synchronous reference frame and takes part in the current controller design. Multiple equations construction is established to solve the parameters of the complex PI current controller. Because the controller satisfies the restrictions of the multiple equations, it can realize good dynamic performance and the coupling characteristic of the three-phase system. In this paper, the CVM is established. The process of construct and solve the multiple equations is analyzed in detail. The accuracy of the inverter system is validated. Finally the simulation and experimental results are given to verify the theoretical analysis.

The concept of virtual synchronous generators (VSGs) is an effective means for improving the stable operation of the grid when the large number of distributed power sources connected to the grid. However, due to its power coupling problem, coupling overshoot and steady-state error occur during power adjustment, which seriously affects the dynamic performance and stability of the system. With this problem in mind, the system model of VSG is established by using a complex vector analysis method. Then the coupling system is analyzed by the bilateral frequency response characteristic curve and pole-zero diagram. On this basis, a dynamic decoupling method based on complex vectors is proposed. Decoupling is obtained by eliminating the poles of the controlled object through the zero points of the controller. After decoupling, when the system performs active power adjustment, the reactive power coupling overshoot is reduced by 83% and the steady-state error is completely eliminated. When the system performs reactive power adjustment, the active power coupling overshoot is reduced by 80%, the dynamic performance and stability of the system have been improved. Simulation and experimental is used to verify the theoretical analysis.

The dual-buck inverter (DBI) does not have a shoot-through problem, and thus, the harmonics caused by the dead-time can be avoided. Besides, the DBI of half-cycle control can reduce the inductor current. However, half-cycle control would cause zero-crossing distortion (ZCD). This article discusses the working principle of DBI and the cause of ZCD. ZCD would lead to grid current distortion, which can be extracted by a high pass filter (HPF). Therefore, the negative feedback of grid current harmonic components can inhibit ZCD. In this article, the half-cycle control method without ZCD is proposed. The logic of half-cycle control is analyzed in detail. The ZCD formation process and the inhibition method is given by the quantitative switching model analysis. What is more, the influence on the control system of the method is discussed. Finally, a simulation model and a prototype of the three-phase DBI have been built to verify the theoretical analysis.

Immobilized protein has advanced in many areas like drug discovery. While this field evolved rapidly over the last three decades, the immobilization platform for the G-protein-coupled receptor (GPCR) remains unpromising due to its instability under the relatively harsh conditions of current methodologies. Taking beta2-adrenoceptor (β2-AR) as an example, we presented here a general strategy for immobilization of GPCRs by combining the His6-tag trap system, conformation-specific aptamer, and target binding induced DNA hybridization. Morphology characterization by diverse assays confirmed a monolayer of β2-AR on the microsphere surface. The radio-ligand binding assay and immuno-transmission electron microscopy showed desirable ligand- and antibody-binding activities. A case study of chromatography using the immobilized receptor as a stationary phase exhibited a demonstrable conformation specificity that enables the selective recognition of the receptor agonists or antagonists. Owing to the competitive strand displacement during the immobilization, the method proved to be capable of sensitively and directly determining the receptor density on the surface which enormously challenges most of the reported assays. This method is possible to turn into a general strategy for the immobilization of GPCRs with a defined orientation, conformation, function, and density, thus paving the way for precisely realizing the receptor–ligand binding interaction and screening the receptor agonist or antagonist with high efficiency.

The SWI/SNF complex is a highly conserved chromatin remodeling complex and can hydrolyze ATP by its catalytic subunit BRG1 or BRM to reconstruct the chromatin. To investigate whether this ATP-dependent chromatin remodeling could affect the DNA conformation, we therefore regulated (knocked down or overexpressed) BRG1/BRMin the cells and applied Fourier transform infrared (FTIR) spectroscopy to probe DNA conformational changes. As a result, we found that BRG1/BRM was indeed associated with the DNA conformational changes, in which knockdown of BRG1/BRMreduced Z-DNA conformation, while overexpression of BRG1/BRMenhanced Z-DNA conformation. This Z-DNA conformational transformation was also verified using the Z-DNA-binding proteins. Therefore, this work has provided a direct analytical tool to probe Z-DNA transformation upon ATP-dependent chromatin remodeling.

Steer-by-wire is a key technology to realize full self-driving for intelligent vehicles, where this is a challenge for steering angle following accurately. Therefore, a hybrid control thinking is proposed to design a model-tuned predictive sliding control approach, which is utilized to realize angle following of the electric motor steer-by-wire system. Here, sliding mode control is used as a core algorithm to be fit for the dynamics characteristics of the steer-by-wire system. Model tuning control is proposed to update model parameters by a receding horizon method, which means that some posteriori knowledge of the control system is utilized to make the model more accurate. Model predictive control is used to optimize the sliding manifold parameters of sliding mode control, which means that some priori knowledge of the control system is used to make the control law much fitter. Then we discuss a series of studies on the steer-by-wire system model and the control algorithm that, collectively, develop an approach of how the hybrid control algorithm precisely makes the front wheel angles follow desired steering commands. The designed approach has been deployed into a steering control unit, and tested in a steering test vehicle to realize the angle following of the electric motor steer-by-wire system. Based on the experimental results and statistical analysis, it can be concluded that the hybrid control thinking is a good idea of how to fuse several algorithms into a control approach, and the model-tuned predictive sliding control approach is a good candidate for the steering angle following of full self-driving vehicles.

GPCRs are dominant targets for approved drugs and the discovery of lead compound targeting them is still challengeable. Affinity-based screening technique is a promising platform to uncover GPCR ligands. However, the intrinsic activities of them are seldom simultaneously determined during the screening. Taking beta2-adrenoceptor (β2AR) as a probe, this work created a strategy for screening GPCR ligands with simultaneous characterization of their downstream G protein binding responses associated with GTP. The strategy included i) the design and expression of a protein miniature formed by β2AR and G protein α-subunit (Gαs) using circularly permuted HaloTag (cpHalo) as a flexible linker; ii) immobilization of the miniature onto silica gel by a click dehalogenation reaction; iii) systematic characterization of the immobilized miniature by fluorescent and chromatographic studies, and iv) simulating of ligand-induced β2AR-Gαssignaling cascade by chromatographic assays using GTP as an indicator. The immobilized miniature exhibited specificity to β2AR and Gαsantibodies and ligands. The specificity is stable at least within fifteen days with the variation less than 1%. The intrinsic activities of β2AR ligands were distinguished by the changes of GTP chromatographic behaviors on Gαs-cpHalo-β2AR column. Agonists strengthened the binding affinity and kinetics of GTP with Gαs, while antagonist did not give any effect on them. With the intrinsic activity evaluation, we believe, it will improve the attributes of chromatographic methods for drug discovery efforts with minimizing false-positive results.

Islanding detection is one of the frontier research problems in the study of distributed grid. The non-detection zone of traditional passive detection method is large, and existing active detection methods for non-detection zones are complicated. Aiming at the above problems, this paper proposes a novel passive islanding detection method with the help of closed-loop frequency control (CFC). In this new method, a high-frequency impedance detection method is combined with CFC to prevent the occurrence of islanding, and the frequency tracking principle and high-frequency impedance characteristics of the CFC are analyzed. Load impedance characteristics under different islanding conditions are also discussed. Simulation and experimental results show that proposed method is able to detect the occurrence of inverter disconnection quickly and accurately, and non-detection zone is also eliminated.

The state‐of‐power (SOP) of a Li‐ion battery (LIB) is an important evaluation index for safety control and energy recovery in electric vehicles. Major state estimation methods are only applicable to fixed room temperature at 20 °C, although the battery capacity and resistance vary dramatically with a change in battery surface temperature in the working process of the battery. This causes significant errors in state estimation if only room temperature is assumed. The inaccurate state may cause further excessive current at high or low temperatures to affect safety and life cycle of the battery. Therefore, a novel state estimation method applicable to various battery surface temperatures is developed here. This method uses capacity–temperature and resistance–temperature relationships from experimental data to more accurately predict battery capacity and resistance over the full temperature range. It then applies the extended Kalman filter (EKF) technique to estimate the state‐of‐charge, and a method of constrained multi‐parameter algorithm (CMPA) to estimate the SOP of LIBs. Simulation and experimental results show that the proposed method can obtain accurate SOP results at different temperatures. A novel state estimation methodconsidering the battery surface temperature is proposed. The capacity and resistance of the Li‐ion battery are tested at different temperatures to find the relations between capacity and temperature and between resistance and temperature for more accurate prediction of the parameters. Then, a method for using a constrained multi‐parameter algorithm (CMPA) and an extended Kalman filter (EKF) technique is used to estimate the state‐of‐power of Li‐ion batteries.

A rhodium(I)-catalyzed highly enantioselective ring-opening and isomerization of cyclobutanols has been developed. The reaction provides a mild, atom-economical, and redox-neutral approach for the synthesis of chiral acyclic ketones bearing a β-tertiary stereocenter. Excellent enantioselectivities and high yields can be achieved using cyclobutanols with alkoxy substituents at the C3 position. Mechanistic studies reveal that cyclobutanol only undergoes intramolecular hydrogen migration, and the formation of a (Z)-unsaturated ketone intermediate is crucial for achieving high enantioselectivity.

Revealing drug–protein interaction is highly important to select a drug candidate with improved drug-like properties in the early stages of drug discovery. This highlights the urgent need to develop assays that enable the analysis of drug–protein interaction with high speed. Herein, this purpose was realized by the development of an affinity chromatographic method with a two-fold higher speed than typical assays like frontal analysis and zonal elution. The method involved synthesis of a stationary phase by immobilizing poly(ADP-ribose) polymerase-1 (PARP1) onto macroporous silica gel through a one-step bioorthogonal reaction, characterization of mutual displacement interaction of two canonical drugs to the immobilized PARP1, determination of the interaction between three (iniparib, rucaparib, and olaparib) drugs and the protein, and validation of these parameters by typical frontal analysis. The numbers of binding sites on the column were (2.85 ± 0.05) × 10–7, (1.89 ± 0.71) × 10–6, and (1.49 ± 0.06) × 10–7M for iniparib, rucaparib, and olaparib, respectively. On these sites, the association constants of the three drugs to the protein were (9.85 ± 0.56) × 104, (2.85 ± 0.34) × 104, and (1.07 ± 0.35) × 105M–1. The determined parameters presented a good agreement with the calculation by typical frontal analyses, which indicated that the current continuous competitive frontal analysis method was reliable for determining drug–protein interaction. Application of the methods was achieved by screening tubeimosides I and II as the bioactive compounds against breast cancer in Bolbostemma paniculatum. Their mechanism may be the interference of DNA repair via down-regulating PARP1and meiotic recombination 11 expressions, thus leading to oncogene mutations and death of cancer cells. The method was high speed since it allowed simultaneous determination of binding parameters between two drugs and a protein with a smaller number of experiments to be performed. Such a feature made the method an attractive alternative for high-speed analysis of drug–protein interaction or the other bindings in a binary system.

This paper focuses on the front wheel angle tracking control problem of the steer-by-wire system subject to unmodeled dynamics, uncertain parameters, external disturbances and measurement noises. Considering the measurement uncertainties of front wheel angle and angular velocity, a new steering dynamics model with matched and unmatched disturbances is built for control design. An unmatched disturbance observer is designed to attenuate the effects of unmatched measurement uncertainties and further improve the angle tracking precision of steady-state. A matched disturbance observer is developed to cancel the effects of matched disturbances, and to alleviate the chattering of sliding mode control. Based on the outputs of these two disturbance observers and the sliding mode controller (SMC), a proportional differential sliding mode control (pdSMC) approach is developed by a new sliding manifold for angle tracking of the steer-by-wire system. The developed approach has been downloaded into a steering control unit, and tested in real-world conditions using vehicle test bench to fully realize electric motor steering by wire in engineering practice. Experimental results show that compared with the SMC controller, the pdSMC controller reduces the mean absolute error of the front wheel angle by 52% and 58.9% in the steering tests of step response and slalom path, respectively.

Introduction:This study aims to analyze the clinical characteristics of patients with obstructive hypertrophic cardiomyopathy (OHCM) undergoing repeated septal reduction therapy (SRT), and preliminarily describe the genotype in the recruited patients.Methods:Patients with OHCM who received repeated SRT were recruited from 2014 to 2019 in Fuwai Hospital. Patients were divided into septal myectomy (SM) group or alcohol septal ablation (ASA) group according to the primary procedure of SRT. Sixteen of these patients underwent genetic testing. Pathogenic mutations were those mutations identified as pathogenic, likely pathogenic, or variants of uncertain significance according to the ACMG criteria.Results:A total of 31 patients (21 males) was included. The average age was 48.7±12.2 years. There were 7 patients in the SM group and 24 patients in the ASA group. Preoperative electrocardiogram showed that 7 patients in the ASA group presented with complete right bundle branch block (CRBBB). After the operation, 4 patients were implanted with permanent pacemakers due to complete atrioventricular block, of which 3 patients were in the ASA group with CRBBB. Pathogenic mutations were identified in 50.0% (8/16) of the study patients. Pathogenic mutations were mostly located in the MYH7 gene (5/9,55.6%), MYBPC3 gene (3/9,33.3%), and TNNT2 gene (1/9,11.1%). There was no difference between patients carrying pathogenic mutations or not, in terms of interventricular septal thickness and left ventricular outflow tract gradient. During the perioperative period, except for one death caused by electrical storm, the remaining patients had no serious complications. The results of follow-up echocardiography showed that except for 2 patients who had left ventricular outflow tract obstruction again, the thickness of interventricular septum and left ventricular outflow tract gradient was significantly lower compared with preoperative echocardiography.Conclusions:In conclusion, the surgery of SM is an effective treatment in OHCM patients with a history of previous SRT procedures. Patients with the first procedure of ASA are at high risk of developing atrioventricular block after a repeated SM.

Introduction:Hypertrophic cardiomyopathy (HCM) is the most prevalent inherited heart disease. The presence of a sarcomere mutation is a powerful predictor of adverse outcomes. Two-thirds of the patients are obstructive HCM (OHCM). Atrial fibrillation (AF), a common complication, is associated with poor long-term prognosis in OHCM patients. However, the effect of sarcomere mutation on the clinical phenotype or prognosis in OHCM patients with AF is unknown.Methods and Results:We retrospectively collected 41 OHCM patients with AF who underwent septal myectomy in Fuwai hospital which were separated into 2 groups, sarcomere mutation (+) group and sarcomere mutation (-) group (n=25 and 16). Statistical analysis was performed by Mann-Whitney Utest, Chi-square test, Kaplan-Meier survival analysis, and log-rank test with SPSS 23.0 and GraphPad 8.0. Patients in sarcomere mutation (+) group were younger (42.0±14.5 vs. 57.6±11.7 years, p=0.001). There was no significant difference between sarcomere mutation (+) and sarcomere mutation (-) group on other baseline variables and prognosis (log-rank p=0.077).Conclusions:In conclusion, we did not find that the presence of a sarcomere mutation worsen the prognosis in OHCM patients with AF. Multi-center prospective studies with large samples are needed to further confirm our results.