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The switch machine, an essential element of railway infrastructure, is crucial in maintaining the safety of railway operations. Traditional methods for fault diagnosis are constrained by their dependence on extensive labeled datasets. Semi-supervised learning (SSL), although a promising solution to the scarcity of samples, faces challenges such as the imbalance of pseudo-labels and inadequate data representation. In response, this paper presents the Semi-Supervised Adaptive Matrix Machine (SAMM) model, designed for the fault diagnosis of switch machine. SAMM amalgamates semi-supervised learning with adaptive technologies, leveraging adaptive low-rank regularizer to discern the fundamental links between the rows and columns of matrix data and applying adaptive penalty items to correct imbalances across sample categories. This model methodically enlarges its labeled dataset using probabilistic outputs and semi-supervised, automatically adjusting parameters to accommodate diverse data distributions and structural nuances. The SAMM model’s optimization process employs the alternating direction method of multipliers (ADMM) to identify solutions efficiently. Experimental evidence from a dataset containing current signals from switch machines indicates that SAMM outperforms existing baseline models, demonstrating its exceptional status diagnostic capabilities in situations where labeled samples are scarce. Consequently, SAMM offers an innovative and effective approach to semi-supervised classification tasks involving matrix data.

This paper investigates the problem of spacing control between adjacent trains in train formation and proposes a distributed train-formation speed-convergence cooperative-control algorithm based on barrier Lyapunov function. Considering practical limitations such as communication distance and bandwidth constraints during operation, not all trains can directly communicate with the leader and obtain the expected trajectory it sends, making it difficult to maintain formation consistency as per the predetermined ideal state. Furthermore, to address the challenge of unknown external disturbances encountered by trains during operation, this paper designs a distributed observer deployed on each train in the formation. This observer can estimate and dynamically compensate for unknown reference trajectories and disturbances solely based on the states of adjacent trains. Additionally, to ensure that the spacing between adjacent trains remains within a predefined range, a safety hard constraint, this paper encodes the spacing hard constraint using barrier Lyapunov function. By integrating nonlinear adaptive control theory to handle model parameter uncertainties, a barrier Lyapunov function-based adaptive control method is proposed, which enables all trains to track the reference trajectory while ensuring that the spacing between them remains within the preset interval, therefore guaranteeing the asymptotic stability of the closed-loop system. Finally, a practical example using data from the Guangzhou Metro Line 22, specifically the route from Shiguang Road Station to Chentougang Station over three stations and two sections, is utilized to validate the effectiveness and robustness of the proposed algorithm.

Implantable LED light sources have received a lot of attention in the field of optogenetic neuromodulation. This type of light modulation enables effective stimulation of neurons. However, as optogenetics moves towards clinical trials, combinatorial photostimulation based on arrays of LED light sources has emerged. This approach inevitably brings about a large increase in transient temperature, resulting in the inability to achieve precise stimulation of cells. We designed a wireless optogenetic hardware system to realize the control of the stimulation mode and temperature of the light source array. At the same time, a set of combined photothermal physical model was established to simulate the photothermal response of the whole experiment. The physical model can effectively guide the wireless optogenetic hardware circuits to perform effective stimulation within a controlled temperature range. Our model provides a new technical approach for photothermal studies in optogenetic clinical trials.

Abstract Background Hypertrophic cardiomyopathy is a commonly inherited heart disease. In addition, single coronary artery (SCA) is a rare congenital anomaly of the coronary arteries. And SCA concomitant with severe hypertrophic obstructive cardiomyopathy (HOCM) has seldom been reported in the literature. However, such cases have not been reported to be treated with the Morrow procedure. Case presentation Herein, we presented a case of a 64-year-old female diagnosed with a single left coronary artery with severe HOCM. The HOCM was treated with the Morrow procedure. The patient was discharged on the seventh postoperative day and was asymptomatic during the follow-up. Conclusion To our knowledge, this is the first study reporting a single left coronary artery with severe HOCM treated with the Morrow procedure. In addition, myocardial protection by cardioplegia antegrade perfusion was safe for the patient with SCA and HOCM.

BackgroundIschemic cardiomyopathy (ICM) induced heart failure (HF) is one of the most common causes of death worldwide. This study aimed to find candidate genes for ICM-HF and to identify relevant biomarkers by machine learning (ML).MethodsThe expression data of ICM-HF and normal samples were downloaded from Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between ICM-HF and normal group were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and gene ontology (GO) annotation analysis, protein–protein interaction (PPI) network, gene pathway enrichment analysis (GSEA), and single-sample gene set enrichment analysis (ssGSEA) were performed. Weighted gene co-expression network analysis (WGCNA) was applied to screen for disease-associated modules, and relevant genes were derived using four ML algorithms. The diagnostic values of candidate genes were assessed using receiver operating characteristic (ROC) curves. The immune cell infiltration analysis was performed between the ICM-HF and normal group. Validation was performed using another gene set.ResultsA total of 313 DEGs were identified between ICM-HF and normal group of GSE57345, which were mainly enriched in biological processes and pathways related to cell cycle regulation, lipid metabolism pathways, immune response pathways, and intrinsic organelle damage regulation. GSEA results showed positive correlations with pathways such as cholesterol metabolism in the ICM-HF group compared to normal group and lipid metabolism in adipocytes. GSEA results also showed a positive correlation with pathways such as cholesterol metabolism and a negative correlation with pathways such as lipolytic presentation in adipocytes compared to normal group. Combining multiple ML and cytohubba algorithms yielded 11 relevant genes. After validation using the GSE42955 validation sets, the 7 genes obtained by the machine learning algorithm were well verified. The immune cell infiltration analysis showed significant differences in mast cells, plasma cells, naive B cells, and NK cells.ConclusionCombined analysis using WGCNA and ML identified coiled-coil-helix-coiled-coil-helix domain containing 4 (CHCHD4), transmembrane protein 53 (TMEM53), acid phosphatase 3 (ACPP), aminoadipate-semialdehyde dehydrogenase (AASDH), purinergic receptor P2Y1 (P2RY1), caspase 3 (CASP3) and aquaporin 7 (AQP7) as potential biomarkers of ICM-HF. ICM-HF may be closely related to pathways such as mitochondrial damage and disorders of lipid metabolism, while the infiltration of multiple immune cells was identified to play a critical role in the progression of the disease.

Over the years, bioinformatics tools have been used to identify functional genes. In the present study, bioinformatics analyses were conducted to explore the underlying molecular mechanisms of angiogenic factors in calcific aortic valve disease (CAVD). The raw gene expression profiles were from datasets GSE153555, GSE83453, and GSE51472, and the angiogenesis-related gene set was from the Gene Set Enrichment Analysis database (GSEA). In this study, R was used to screen for differentially expressed genes (DEGs) and co-expressed genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) Pathway enrichment analysis were performed on DEGs and validated in clinical samples. DEGs in CAVD were significantly enriched in numerous immune response pathways, inflammatory response pathways and angiogenesis-related pathways. Nine highly expressed angiogenesis-related genes were identified, of which secretogranin II (SCG2) was the most critical gene. MiRNA and transcription factors (TFs) networks were established centered on five DEGs, and zinc finger E-box binding homeobox 1 (ZEB1) was the most important transcription factor, verified by PCR, immunohistochemical staining and western blotting experiments. Overall, this study identified key genes and TFs that may be involved in the pathogenesis of CAVD and may have promising applications in the treatment of CAVD.

Abstract Background Cardiac foreign bodies are extremely rare in clinical patients, especially when foreign bodies damage the internal structure of the heart coincidentally after they penetrate the heart. Case presentation Here, we report the case of a two-year-old girl whose heart was penetrated by a needle, which triggered mitral valve regurgitation and endocarditis. After a comprehensive inspection, accurate judgment and surgical preparation, we removed the needle and repaired her mitral valve. Fortunately, she recovered postoperatively. Conclusion From this case, we can know that when cardiac foreign bodies are suspected, ultrasound is an important inspection method. Moreover, the approaches for handling each such case are different depending on the associated injuries.

Double-chambered right ventricle (DCRV) is a rare congenital heart defect in adults, manifesting with progressive right ventricular outflow tract obstruction. We describe the first case of DCRV coexisting with hypertrophic cardiomyopathy, which is complicated by atrial flutter. A middle-aged woman with recurrent symptomatic atrial flutter who had previously been diagnosed with biventricular hypertrophic cardiomyopathy was admitted to our department. Echocardiography and cardiac magnetic resonance revealed asymmetrical interventricular septal hypertrophy, and abnormal muscle bundles within the right ventricle, generating an obstructive gradient. Genetic testing detected a hypertrophic cardiomyopathy-associated mutation: MYH7, c.4135G > A, p. Ala1379Thr. A diagnosis of DCRV complicated by hypertrophic cardiomyopathy and atrial flutter was made. Surgical intervention was performed, which included radiofrequency ablation, removal of abnormal muscle bundles, and ventricular septal defect repair. Intraoperative transesophageal echocardiography demonstrated the well-corrected right ventricular outflow tract. Free of early postoperative complications, the patient was discharged in sinus rhythm on the 11th day after the surgery. Unfortunately, the patient died from a sudden death 38 days following the surgery. In conclusion, the coexistence of DCRV with hypertrophic cardiomyopathy in patients is an uncommon condition. The present case highlights the importance of diagnostic imaging in the management of this disorder.

Because of the requirements of payload capability, flight range, and maneuverability, hypersonic aircraft demand high aerodynamic performance. Waveriders have attracted significant attention because of their high lift-to-drag ratios in hypersonic states. Many methods to design waveriders have been proposed for more than 60 years, among which the osculating method features unique advantages in terms of design space, efficiency, and flexibility. Moreover, nearly all waverider design methods can be realized using this approach. This paper presents an overview of research on waverider design methodologies using osculating theory developed until 2023. The design theory and detailed implementation of the osculating cone method are first described, followed by the progress and improvement of the method and the derived osculating flowfield method. The planform-customized waverider from the osculating cone method, which has developed rapidly in recent years, is discussed emphatically. In addition, the connection between the osculating cone and other waverider design methods is plotted to show its powerful applicability. The application of the osculating waverider in practical aircraft design is also summarized. Finally, some perspectives and suggestions for future development are concluded. [ABSTRACT FROM AUTHOR]

The wind-tunnel experiments for the double-swept waverider were carried out in subsonic, transonic, and supersonic states, aiming to validate its potential advantages in wide-speed performances. The test configurations were generated using the planform-customized waverider design, which was developed from the osculating-cone method. Two experimental models of the double-swept waveriders with bend and cusp heads were fabricated, and a single-swept configuration was built as a comparable model. A series of experiments were performed in the FD-06 wind tunnel of the China Academy of Aerospace Aerodynamics at a subsonic Mach number of Ma=0.4; transonic Mach numbers of Ma=0.7, 0.8, and 0.9; and a supersonic Mach number of Ma=2.0. The results from the wind-tunnel tests were examined by combining the numerical simulations. As the Mach number increased, the lift-to-drag (L/D) ratios of the double-swept waveriders decreased slightly when Ma≤0.8; but when Ma>0.8, their L/D dropped sharply. Moreover, the double-swept waveriders were unstable in the longitudinal direction in the subsonic state, and their longitudinal stability was obviously improved as the Mach number went up. When the Mach number was greater than 0.9, they became statically stable. Compared with the single configuration, the double-swept waverider exhibited increased L/D in subsonic and transonic states, as well as improved longitudinal stability in the wide-speed range, but it exhibited a decreased L/D in the supersonic state. [ABSTRACT FROM AUTHOR]

Wind-tunnel tests of the double-swept waverider were performed in the off-design states, aiming to analyze its potential advantage in wide-speed performances. The test configurations were generated using the planform-customized waverider design, developed from the osculating-cone method. Then models of double-swept waveriders with the bend and cusp head were fabricated, and compared with a model of a single-swept waverider also built using the same method. A variety of experiments in their on-design and off-design states were performed in the hypersonic wind tunnel FD-07 of our institute, and computational fluid dynamics were employed to simulate flowfields as a supplement. According to the wind-tunnel tests and flow simulations, the aerodynamic forces and longitudinal stability were obtained and analyzed. The aerodynamic performance of the double-swept waverider did not fall significantly when deviating from the design states. The general trend was that, as Mach number increased, the lift-to-drag ratios dropped slightly. The double-swept waverider featured large longitudinal stability margin in hypersonic states, and the change in Mach number had little effect on longitudinal stability. Compared with the single configuration, the double-swept waverider suffered a decrease in lift-to-drag ratio, but showed a significant improvement in longitudinal stability. [ABSTRACT FROM AUTHOR]

The double swept waverider is a classic example of the planform-customized osculating-cone waveriders, delivering satisfactory performances over a wide range of velocities. The nonlinear increase in the lift of double swept waveriders at high angles of attack is of vital interest. In this paper, the aerodynamic performance of the double swept waverider is calculated and compared with single swept waveriders. The results suggest that the nonlinear increase in the lift of the double swept waverider is stronger than that of the equal-planform-area single swept waverider, and it increases with the Mach number. Some scholars have proposed the "vortex lift" to explain the nonlinear increase in lift, but it is controversial because the main lift of the waverider comes from the lower rather than the upper surface. This paper proposes that this nonlinear increase is related to the attachment of the shock wave influenced by the leading-edge sweep angle. The shock wave is more inclined to attach under the lower surface at a smaller sweep angle than a larger one as the angle of attack increases. When the shock wave attaches, the increase in pressure via the angle of attack is nonlinear, leading to a nonlinear increase in lift. When the shock wave detaches, the increase in lift is approximately linear. [ABSTRACT FROM AUTHOR]

Objectives We sought to explore and create a reliable, convenient, and economic hyperkinetic pulmonary artery hypertension (PAH) model and confirm the exact time of establishing a reversible or irreversible model to serve as a platform for future studies. Methods We used a common carotid artery and jugular vein shunt with an anastomosis and cuff to create a hyperkinetic PAH model in rabbits. At 1, 2, 3, 6, and 12 months postoperatively, the systolic pressure, mean pulmonary arterial pressure, and mean arterial pressure were measured by catheterization and the right ventricle hypertrophy index was calculated. Pathologic changes in the small pulmonary arteries were observed with hematoxylin and eosin staining, and the Heath-Edwards classification system was used to evaluate PAH. Results The anastomosis and cuff graft groups both increased in systolic pressure, mean pulmonary arterial pressure (P < .05), and right ventricle hypertrophy index (P < .05). However, the anastomosis method resulted in a lower mortality rate, greater patency, and overall success rate compared with the cuff graft method (P < .05). Furthermore, from the observed pathologic changes and the Heath-Edwards classification system, a reversible and an irreversible PAH model was established at 3 and 6 months postoperatively, respectively. Conclusions The common carotid artery and jugular vein anastomosis method is a stable hyperkinetic PAH model in rabbits. Reversible and irreversible PAH models were established at 3 and 6 months postoperatively, respectively. [ABSTRACT FROM AUTHOR]