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【Objective】Single-photon detection and single-photon ranging systems have widespread applications in three-dimensional imaging and long-distance spatial remote sensing. However, device limitations and background noise from the sun light limit the application to only nighttime conditions.【Methods】We have improved traditional laser radar systems by implementing all-fiber optics systems with ultra-narrowband fiber optic filtering, leading to significantly improved system stability. By implementing mechanical motion control, we are able to attain single-photon imaging systems with ultra-wide scanning and ultra-high resolution. The systems can operate in optical environments that are typically challenging, such as daytime or foggy weather. Moreover, the laser radar system is designed based on the 1 550 nm wavelength which has good atmospheric penetration and low transmission loss, enhancing its ability to work in foggy and rainy conditions.【Results】In a foggy condition with a visibility of about 500 m, the system achieves three-dimensional imaging of objects 1.6 km away, which is a distance 3 times longer than the visibility at the time. The distance resolution can be significantly enhanced by optimizing the intensity and distance information of the histogram using the minimized negative logarithmic likelihood function, with the assistance of a high-resolution time/digital converter and the model constructed by the system response function of the laser radar. Compared to the maximum value method with a distance resolution of 0.05 m, this system achieves a distance resolution of 0.006 m via the minimized negative logarithmic likelihood function method. Additionally, the image normalization processing is performed to suppress fluctuations in photon technology and eliminate noise in the image. The 1 550 nm all-fiber laser radar system has strong mechanical stability and can work in adverse weather conditions.【Conclusion】It has significant application value in remote sensing and mapping, ground and vehicle-mounted laser radar, and other fields.

The Cu–15Ni–8Sn alloy ingot was prepared in the medium-frequency induction melting furnace. The hot extruded alloy was treated by solid solution at 840 °C for 60 min and aging at 400 °C for different times (0 miñ480 min). The effect of aging time on the evolution of the nanophase of Cu–15Ni–8Sn alloy and the strengthening-toughening mechanism were studied. The results show that at the beginning of aging, the alloy undergoes spinodal decomposition, the wavelength of the modulated structure is approximately 3∼7 nm, the ordered phase transformation of D022 and L12 occurs simultaneously, and the ordered phase size is approximately 5 nm. With the extension of aging time, the modulated structure became coarser, and the wavelength of the modulated structure increased to 5–9 nm. At the same time, the D022 ordered phase changed to the L12 ordered phase, and a continuous distribution of elliptical discontinuous precipitation appeared at the grain boundary. The ratio of the long and short axes of the discontinuous precipitation was approximately 4.7. In the late aging period, the D022 ordered phase was basically transformed into the L12 ordered phase, and discontinuous precipitation, which is incompatible with the matrix, extended into the crystal. After 120 min of aging at 400 °C, the hardness, strength, and elongation of the alloy are 105.4 HRB, 839.8 MPa and 9.6 %, respectively. The peak-aging states D022 and L12 coexist in an orderly phase at the nanoscale, and this nanoscale strengthening phase is completely integrated with the matrix, which improves the strength and toughness of the alloy. The research results can provide support for the development of high-performance copper alloys in the ocean.

Abstract The pathogenesis of intervertebral disc degeneration (IVDD) is attributed to metabolic dysregulation within the extracellular matrix and heightened apoptosis of nucleus pulposus cells (NPC). Therefore, a potential therapeutic strategy for managing IVDD involves the reestablishment of metabolic equilibrium within the extracellular matrix and the suppression of excessive myeloid cell apoptosis. The microRNA, miR-5590, displays marked differential expression in degenerative nucleus pulposus (NP) tissues and exerts a direct influence on the regulation of DDX5 expression. This, in turn, modulates mammalian target of rapamycin (mTOR) phosphorylation, thereby impacting autophagy and apoptosis. However, ensuring the smooth delivery of miRNA to a specific injury site poses a significant challenge. To address this issue, a multifunctional DNA hydrogel was developed and subsequently loaded with miR-5590 via spherical nucleic acids (SNAs) for the treatment of IVDD. The hydrogel, which exhibits versatility, has the potential to be administered through injection at the site of injury, resulting in a consistent and prolonged release of miR-5590. This leads to the creation of a genetic microenvironment within the NP, which triggers the onset of autophagy in NPCs and subsequently suppresses apoptosis. As a result, this process regulates the metabolic equilibrium within the extracellular matrix, thereby impeding the in vitro and in vivo progression of IVDD. The amalgamation of miRNAs and biomaterials offers a promising therapeutic strategy for the management of IVDD in clinical settings.

This study constructs an interactive teaching platform based on speech recognition technology for language courses in colleges and universities. The study begins with preprocessing speech signals, including sampling, enhancement, pre-emphasis and other steps. Subsequently, speech features are extracted using Improved Mel Falling Spectral Coefficients (IMFCC), and features are optimized by combining Principal Component Analysis (PCA). In addition, the study uses the Long Short-Term Memory (LSTM) network and Gated Recurrent Unit (GRU) to improve speech recognition’s accuracy and efficiency. The experimental results show that the method in this study achieves an average accuracy of 98% in classroom speech emotion recognition, which is a significant improvement over the traditional ADASYN method. This paper also provides an in-depth study of classroom interaction behavior by comprehensively analyzing the speech recognition results. The study shows that the platform can effectively promote the interaction between teachers and students and improve the quality of teaching. This study provides an efficient interactive tool for language teaching in colleges and universities, which helps to realize a personalized and dynamic teaching process.

The drag torque of the wet clutch affects the efficiency of the transmission, and the engagement torque of the clutch affects the reliability of the transmission. However, reducing the drag torque and increasing the engagement torque are generally contradictory. This study takes the wet friction clutch as the research object, and takes the inner diameter, outer diameter, radial groove depth, radial groove width and number of radial grooves, friction plate clearance of the wet clutch as the optimal design variables. The minimum drag torque and maximum engagement torque are the optimization objectives, the mathematical model of the optimization design is established, and the solution method of the optimization toolbox of Matlab is given. Taking a fracturing truck gearbox clutch as an example, the multi-objective optimization design is carried out. After optimization, the drag torque is reduced by 31.67%, and the engagement torque is increased by 33.51%. The results show that the optimization method used in this study is effective and can provide theoretical reference for the design of the friction plate structure and the optimization of clutch parameters.

Porous mullite ceramics were prepared by pressing molding and sintering method, using coal gangue and bauxite as raw materials, hollow glass microspheres as pore-forming agent. The effects of addition amount of hollow glass microspheres and sintering temperature on phase composition, microstructure, flexural resistance and acid and alkali corrosion resistance were studied. The results show that increasing the amount of hollow glass microspheres can increase the porosity of porous ceramics; the addition of hollow glass microspheres can promote the formation of mullite phase and reduce the sintering temperature. In a certain temperature range, increasing the sintering temperature can also increase the porosity, but when the sintering temperature is over 1350 ℃, the porosity begins to decline. Porous mullite ceramics with porosity of 33.23% and flexural strength of 56.41 MPa can be obtained by keeping the molar ratio of Al2O3∶SiO2=3∶2 and adjusting the addition amount of hollow glass microspheres to 1.68%(mass fraction) and sintering at 1350 ℃ for 2 h, which has good acid and alkali corrosion resistance.

Electrochemical energy storage is flexible and efficient, and it is an important direction for the development of large-scale power energy storage technology. Liquid metal battery (LMB) uses liquid metals and molten inorganic salts as electrodes and electrolytes, respectively, to fundamentally avoid the life-limiting problem of traditional batteries. LMB has the advantages of long life, low cost, and large capacity, and has broad application prospects in the field of power system energy storage. This paper mainly introduced the working principle of LMB, focused on its development history and important research progress, and pointed out the limitations and challenges of existing battery systems. On this basis, the key development directions of LMB were discussed and clarified.

The eastern Qinling orogenic belt, located in the conjoint region between the Neo-Tethys tectonic domain and the western Pacific tectonic domain, is key to understanding the tectono-sedimentary evolution of the East Asian interior. Extensive Late Cretaceous–Cenozoic fluvial and lacustrine deposits within the eastern Qinling orogen provide ideal archives of tectono-sedimentary evolution in Fenwei, the eastern Qinling orogen. We present an integrated rock magnetism and anisotropy of magnetic susceptibility (AMS) study of a Middle Eocene–Early Oligocene succession in the Lushi Basin, eastern Qinling region. Our rock magnetic results suggest that hematite and magnetite are the main magnetic carriers of remanence, while χ−T curves, hysteresis loops, and low values of bulk susceptibility indicate that paramagnetic minerals are major contributors to AMS in the Lushi Basin. Nevertheless, the anomalous magnetic fabrics in the Zhangjiacun and Lushi Formations may result from the contribution of the iron-bearing carbonates in deposits. The clustering of the minimum principal axes nearly vertical to the bedding plane and the well-defined NW–SE magnetic lineation almost parallel to the dip of the bounding fault suggest that the AMS of the Dayu Formation is not a sedimentary fabric but an incipient deformation magnetic fabric. The pronounced NW–SE magnetic lineation indicates the NW–SE stretching of the Lushi Basin during the Late Eocene–Earliest Oligocene, which may have been caused by the combined effects of the India–Eurasia collision and the subduction of the western Pacific plate.

Agriculture holds a pivotal role in the progress of human society. The challenges stemming from a burgeoning population, land degradation, water scarcity, and urbanization have intensified the need for more efficient agricultural production. While smart farming brings significant benefits to farmers and agricultural output, it also introduces complex cybersecurity risks to agricultural production. The security of the physical layer in smart agriculture is intricately tied to crop growth and yield, with indirect implications for the security of the network and application layers. This paper introduces a novel intrusion detection scheme based on CatBoost for the physical layer and evaluates its effectiveness using the publicly available ToN_IOT dataset. In binary classification results, the scheme achieves a remarkable recognition accuracy of 99.94%, along with a precision and recall of 99.88%. In multi-classification results, the scheme outperforms other existing solutions across all metrics. The experimental findings clearly illustrate the exceptional recognition accuracy of this implemented method against physical layer attacks within the domain of smart agriculture. Furthermore, the system’s implementation ensures the security of input data for the smart agriculture network layer, cloud, and blockchain applications.

Single-grain U-Pb dating of detrital zircons is regarded as an efficient and effective technique to differentiate the contribution of discrete sources. However, its application to the extensive Chinese Loess Plateau (CLP) yields rather complex information in provenance discrimination. The Xining loess was deposited in the Northeastern Tibetan Plateau (NETP), and the detrital zircon U-Pb chronology study can not only obtain provenance information but also provide an important basis to discuss the contribution of the detrital materials from the Northern Tibetan Plateau (NTP) to the CLP. Results of the detrital zircon morphology suggest that zircons may have undergone intense physical weathering and multiple recirculations, and may also indicate the high complexity of the source. Detrital zircon U-Pb age results from different sedimentary layers of the Xining loess reveal there are no obvious temporal variations in the provenance of the Xining loess since ~1.3 Ma and materials may ultimately be eroded from the NTP and the Central Asian Orogenic Belt (CAOB), although the relative contribution of detritus from the two sources may slightly vary through time. The U-Pb age spectra of the Xining loess are highly similar to that of typical loess sites in the western-central CLP, suggesting that the provenance areas of the CLP and the Xining loess may be largely consistent, but the possibility of a small difference of provenance cannot be ruled out.

The development of X-ray-absorbing scintillating nanoparticles is of high interest for solving the short penetration depth problem of visible and infrared light in photodynamic therapy (PDT). Thus, these nanoparticles are considered a promising treatment for several types of cancer. Herein, gadolinium oxide nanoparticles doped with europium ions (Gd2O3:Eu3+) were obtained by using polyvinyl alcohol as a capping agent. Hybrid silica nanoparticles decorated with europium-doped gadolinium oxide (SiO2-Gd2O3:Eu3+) were also prepared through the impregnation method. The synthesized nanoparticles were structurally characterized and tested to analyze their biocompatibility. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy confirmed the high crystallinity and purity of the Gd2O3:Eu3+ particles and the homogeneous distribution of nanostructured rare earth oxides throughout the fumed silica matrix for SiO2-Gd2O3:Eu3+. Both nanoparticles displayed stable negative ζ-potentials. The photoluminescence properties of the materials were obtained using a Xe lamp as an excitation source, and they exhibited characteristic Eu3+ bands, including at 610 nm, which is the most intense transition band of this ion. Cytotoxicity studies on mouse glioblastoma GL261 cells indicated that these materials appear to be nontoxic from 10 to 500 μg·mL−1 and show a small reduction in viability in non-tumor cell lines. All these findings demonstrate their possible use as alternative materials in PDT.

In this paper, we describe the formatting guidelines for Conference Proceedings. Whether the user similarity calculation is reasonable in the traditional collaborative filtering recommendation algorithm directly affects the result of the collaborative filtering recommendation algorithm. This paper proposes a probabilistic matrix factorization recommendation algorithm with user trust similarity which combines improved similarity of users’ trust and probability matrix factorization recommendation method. The results show that proposed algorithm could relieve user cold start issues and effectively reduce the error of recommendation.

Abstract A size-controlled Zn(OH)2 template is used as a case study to explain the chemical strategy that can be executed to chemically engineering various nanoscale cavities. Zn(OH)2 octahedron with 8 vertices and 14 edges is fabricated via a low temperature solution route. The size can be tuned from 1 to 30 μm by changing the reaction conditions. Two methods can be selected for the hollow process without loss of the original shape of Zn(OH)2 template. Ion-replacement reaction is suitable for fabrication of hollow sulfides based on the solubility difference between Zn(OH)2 and products. Controlled chemical deposition is utilized to coat an oxide layer on the surface of Zn(OH)2 template. The abundant hydroxyl groups on Zn(OH)2 afford strong coordination ability with cations and help to the coating of a shell layer. The rudimental Zn(OH)2 core is eliminated with ammonia solution. In addition, ZnO-based heterostructures possessing better chemical or physical properties can also be prepared via this unique templating process. Room-temperature photoluminescence spectra of the heterostructures and hollow structures are also shown to study their optical properties.

In this work, we study the nucleation of quasicrystals from liquid or periodic crystals by developing an efficient order–order phase transition algorithm, namely, the nullspace-preserving saddle search method. In particular, we focus on nucleation and phase transitions of the decagonal quasicrystal (DQC) based on the Lifshitz–Petrich model. We present the nucleation path of DQC from the liquid and demonstrate one- and two-stage transition paths between DQC and periodic crystals. We provide a perspective of the group–subgroup phase transition and nucleation rates to understand the nucleation and phase transition mechanisms involving DQC. These results reveal the one-step and multi-step modes of symmetry breaking or recovery in the phase transition from DQC, where the multi-step modes are more probable. [ABSTRACT FROM AUTHOR]

Androgen has long been recognized for its pivotal role in the sexual dimorphism of cardiovascular diseases, including aortic aneurysms (AAs), a devastating vascular disease with a higher prevalence and fatality rate in men than in women. However, the mechanism by which androgen mediates AAs is largely unknown. Here, we found that male, not female, mice developed AAs when exposed to aldosterone and high salt (Aldo-salt). We revealed that androgen and androgen receptors (ARs) were crucial for this sexually dimorphic response to Aldo-salt. We identified programmed cell death protein 1 (PD-1), an immune checkpoint, as a key link between androgen and AAs. Furthermore, we demonstrated that administration of anti-PD-1 Ab and adoptive PD-1-deficient T cell transfer reinstated Aldo-salt-induced AAs in orchiectomized mice and that genetic deletion of PD-1 exacerbated AAs induced by a high-fat diet and angiotensin II (Ang II) in nonorchiectomized mice. Mechanistically, we discovered that the AR bound to the PD-1 promoter to suppress the expression of PD-1 in the spleen. Thus, our study unveils a mechanism by which androgen aggravates AAs by suppressing PD-1 expression in T cells. Moreover, our study suggests that some patients with cancer might benefit from screenings for AAs during immune checkpoint therapy., Introduction Aortic aneurysms (AAs) are defined as a permanent localized dilation of the aorta and can be classified as thoracic aortic aneurysms (TAAs) and abdominal aortic aneurysms (AAAs) (1). AAs [...]