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This work addresses the low pyroelectric coefficient that limits the practical application of lithium niobate (LN) crystals. A defect modulation process based on reduction annealing treatment is proposed. This reduction annealing treatment increased the pyroelectric coefficient of LN crystals maximally to 3.362 × 10−4 C/m2K. At room temperature, the voltage responsivity figure of merit (FV) and detectivity figure of merit (FD) were both improved more than three-fold. All material properties exceeded those of commercial lead zirconate titanate (PZT) ceramic. This process achieves the simultaneous modulation of high pyroelectric coefficients and low impedance in LN crystals. Based on the LN crystals with optimized properties, pyroelectric infrared detectors (center wavelength 9.4 μm) without external matching resistors were prepared. The response voltage of the detector reached 2.8 times that of commercial PZT detectors while exhibiting lower noise, and has achieved practical applicability. This work provides a simple and efficient method for developing environmentally friendly, low-cost, high-sensitivity pyroelectric infrared detectors. It also establishes the foundations for the application of LN crystals in emerging pyroelectric detection fields.

During its operation, a rotor system can be exposed to multiple faults, such as rub-impact, misalignment, cracks and unbalancing. When a crack fault occurs on the rotor shaft, the vibration response signals contain some nonlinear components that are considerably tougher to be extracted through some linear diagnosis methods. By combining the Nonlinear Output Frequency Response Functions weighted contribution rate (WNOFRFs) and Kullback–Leibler (KL) divergence, a novel fault diagnosis method of improved WNOFRFs is proposed. In this method, an index, improved optimal WNOFRFs (IOW), is defined to represent the nonlinearity of the faulty rotor system. This method has been tested through the finite element model of a cracked rotor system and then verified experimentally at the shaft crack detection test bench. The results from the simulation and experiment verified that the proposed method is applicable and effective for cracked rotor systems. The IOW indicator shows high sensitivity to crack faults and can comprehensively represent the nonlinear properties of the system. It can also quantitatively detect the crack fault, and the relationship between the values of IOW and the relative depth of the crack is approximately positively proportional. The proposed method can precisely and quantitatively diagnose crack faults in a rotor system.

This paper introduces a novel model-free fractional-order composite control methodology specifically designed for precision positioning in permanent magnet synchronous motor (PMSM) drives. The proposed framework ingeniously combines a composite control architecture, featuring a super twisting double fractional-order differential sliding mode controller (STDFDSMC) synergistically integrated with a complementary extended state observer (CESO). The STDFDSMC incorporates an innovative fractional-order double differential sliding mode surface, engineered to deliver superior robustness, enhanced flexibility, and accelerated convergence rates, while simultaneously addressing potential singularity issues. The CESO is implemented to achieve precise estimation and compensation of both intrinsic and extrinsic disturbances affecting PMSM drive systems. Through rigorous application of Lyapunov stability theory, we provide a comprehensive theoretical validation of the closed-loop system’s convergence stability under the proposed control paradigm. Extensive comparative analyses with conventional control methodologies are conducted to substantiate the efficacy of our approach. The comparative results conclusively demonstrate that the proposed control method represents a significant advancement in PMSM drive performance optimization, offering substantial improvements over existing control strategies.

Background Generalized joint laxity (GJL) may affect chronic lateral ankle instability (CLAI) treatment. Short-term results of the arthroscopic-assisted modified Karlsson technique in CLAI were compared for GJL and non-GJL cases. Methods This retrospective analysis included 75 CLAI patients admitted to Jincheng People’s Hospital from August 2019 to August 2023. Patients were diagnosed with CLAI based on clinical history, physical examination, and imaging findings. Twenty-five patients had concomitant GJL (hypermobile group), while fifty did not (non-hypermobile group). Both groups underwent arthroscopic-assisted modified Karlsson surgery. General characteristics and joint function were compared 6 months postoperatively. Ankle function was assessed using the anterior drawer test (ADT), AOFAS ankle score, and Karlsson score before and after surgery. Results Preoperative ADT displacement was similar between groups (9.8 ± 1.9 vs. 9.5 ± 1.7 mm, P  = 0.51), but at 6 months postoperatively, the hypermobile group exhibited greater residual laxity (4.2 ± 1.3 vs. 2.8 ± 0.9 mm, P  = 0.001). Functional scores improved significantly in both groups ( P  < 0.05), though the hypermobile group had lower final AOFAS (82.4 ± 6.3 vs. 88.1 ± 5.7, P  = 0.003) and Karlsson scores (80.5 ± 7.2 vs. 86.3 ± 6.8, P  = 0.004) compared to controls.hypermobile group. Conclusion All patients had increased ankle function and clinical efficacy after the arthroscopy-assisted modified Karlsson treatment. Concomitant GJL patients had worse short-term results than those without GJL.

Stock time-series data has the characteristics of high dimensionality and nonlinearity, which brings great challenges to stock forecasting. Aiming at the impact of stock correlation and the prediction information contained in stock image features, we propose a long short-term memory model based on clustering and image feature extraction, named Kmeans-CAE-LSTM. Firstly, the Kmeans algorithm is used for stock clustering, where the most correlated stocks are found. Secondly, a convolutional autoencoder (CAE) is applied to extract stock price image features. Finally, the stock technical data and image features are respectively input into the double-layer long-term short-term memory network to predict the stock price of the next trading day. The empirical research results on 11 industries in China’s stock market show that the hybrid model has achieved the best prediction effect, which further proves the predictive ability of stock image data and can provide investors with new ideas for stock prediction and asset portfolio.

Wooden structures in China’s ancient buildings hold highly historical and cultural values. There is an urgent need to repair and replace the damaged wooden structures after hundreds and thousands of years of exposure to weather. Unfortunately, to date there is still a lack of insightful understanding on how the chemical structure, composition, and micro-morphology evolve over the long-term natural aging before artificial ancient timbers can be developed. This work aims to systematically examine the outer surface, middle layer, and inner surface of the same piece of Chinese fir (Cunninghamia lanceolate) collected from an ancient Chinese building. Based on qualitative and quantitative analysis, both cellulose and hemicellulose in aged woods are found to experience significant degrees of degradation. The crystalline regions of cellulose are also determined to undergo moderate degradation as compared to the control fresh wood. In comparison, the lignin basically remains unchanged and its content in the inner layer slightly increases, as evidenced by more free phenol groups determined. Relative to the outer and inner layer, the middle layer of the ancient wood shows the lowest degree of degradation close to that of the fresh wood. This work offers guidelines for fabricating artificial ancient woods to repair the destroyed ones in China’s ancient architectures.

Clinical efficacy of treatments against non-obstructive azoospermia (NOA), which affects 1% of men, are currently limited by the incomplete understanding of NOA pathogenesis and normal spermatogenic microenvironment. Here, we profile >80,000 human testicular single-cell transcriptomes from 10 healthy donors spanning the range from infant to adult and 7 NOA patients. We show that Sertoli cells, which form the scaffold in the testicular microenvironment, are severely damaged in NOA patients and identify the roadmap of Sertoli cell maturation. Notably, Sertoli cells of patients with congenital causes (Klinefelter syndrome and Y chromosome microdeletions) are mature, but exhibit abnormal immune responses, while the cells in idiopathic NOA (iNOA) are physiologically immature. Furthermore, we find that inhibition of Wnt signaling promotes the maturation of Sertoli cells from iNOA patients, allowing these cells to regain their ability to support germ cell survival. We provide a novel perspective on the development of diagnostic methods and therapeutic targets for NOA. Non-obstructive azoospermia affects 1% of men. Here, authors perform single-cell transcriptomic analysis of human testicular cells from healthy donors and non-obstructive azoospermia patients and find that inhibition of Wnt signaling promotes the maturation of Sertoli cells from patients.

cGAS-STING pathway is a key DNA-sensing machinery and emerges as a promising target to overcome the immunoresistance of solid tumors. Here we describe a bovine serum albumin (BSA)/ferritin-based nanoagonist incorporating manganese (II) ions and β-lapachone, which cooperatively activates cGAS-STING signaling in dendritic cells (DCs) to elicit robust adaptive antitumor immunity. Mn 2+ -anchored mannose-modified BSAs and β-lapachone-loaded ferritins are crosslinked to afford bioresponsive protein nanoassemblies, which dissociate into monodispersive protein units in acidic perivascular tumor microenvironment (TME), thus enabling enhanced tumor penetration and spatiotemporally controlled Mn 2+ and β-lapachone delivery to DCs and tumor cells, respectively. β-lapachone causes immunogenic tumor cell apoptosis and releases abundant dsDNA into TME, while Mn 2+ enhances the sensitivity of cGAS to dsDNA and augments STING signaling to trigger downstream immunostimulatory signals. The cGAS-STING nanoagonist enhances the tumor-specific T cell-mediated immune response against poorly immunogenic solid tumors in vivo, offering a robust approach for immunotherapy in the clinics. Manganese has a crucial role in cGAS-STING-mediated DNA sensing and has emerged as a STING agonist. Here the authors report the design and characterization of a nanosystem incorporating manganese ions and the chemotherapeutic drug β-lapachone, inducing T-cell mediated anti-tumor immune responses in preclinical cancer models.

Constructing photocatalytically active and stable covalent organic frameworks containing both oxidative and reductive reaction centers remain a challenge. In this study, benzotrithiophene-based covalent organic frameworks with spatially separated redox centers are rationally designed for the photocatalytic production of hydrogen peroxide from water and oxygen without sacrificial agents. The triazine-containing framework demonstrates high selectivity for H 2 O 2 photogeneration, with a yield rate of 2111 μM h −1 (21.11 μmol h −1 and 1407 μmol g −1 h −1 ) and a solar-to-chemical conversion efficiency of 0.296%. Codirectional charge transfer and large energetic differences between linkages and linkers are verified in the double donor-acceptor structures of periodic frameworks. The active sites are mainly concentrated on the electron-acceptor fragments near the imine bond, which regulate the electron distribution of adjacent carbon atoms to optimally reduce the Gibbs free energy of O 2 * and OOH* intermediates during the formation of H 2 O 2 . In this study, benzotrithiophene-based covalent organic frameworks with spatially separated oxidative and reductive reaction centers are rationally designed for photocatalytic production of H 2 O 2 from water and oxygen without sacrificial agents.