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The rock burst frequently occurs in the roadways with top coal, and the roof disasters are particularly severe under dynamic stress in China. In order to explore the classification and instability mechanisms of anchoring structures in the roadways with top-coal, analog simulation experiments, theoretical analysis, and data statistics were used under the engineering background of the large-area rock burst roof failure in the Working Face 301 of a mine in Shaanxi Province, China. The dynamic load response characteristics of the stress, displacement, and surface acceleration of the surrounding rock in the roadways with top coal were analyzed. The classification characteristics of the roof anchoring structure under the influence of top coal thickness and cables were studied. The stress response mechanism of the roadways with top coal under elastic waves was explored, and the instability mechanism of the anchoring “beam arch” structure was proposed. The rock burst resistance of the air-return roadway in the Working Face 301 was evaluated, and the corresponding optimization schemes for the “beam-arch” composite structure were proposed. The results show that ① the monitoring data of stress and displacement of the surrounding rock in the roadways with top coal under dynamic stress verify the existence of internal and external beam or arch anchoring structures in the roof. Due to the increase in the thickness of top coal, there is a transition from “beam” to “arch” in the anchoring structure of the inner layer of the roof; ② based on the relative relationship between the thickness of the top coal and the cables, the roof anchoring structure is divided into “superimposed-beam and arch” for thin top coal, “composite-beam and arch” for thick top coal, and “combined arch” for extra thick top coal. A critical thickness index for the transformation of thick coal beams from “beam” to “arch” is established; ③ the instability mechanism of the beam structure and the arch structure is that they fail after reaching their tensile and shear strength limits under dynamic and static stress, respectively. The amplification effect of the “beam-arch” composite structure on the load stress is significantly affected by its size; ④ the bearing strength of the inner arch in the "combined arch" structure is relatively low. Increasing the length of cables can increase the thickness of the inner arch, and the corresponding “combined arch” structure’s bearing strength increases significantly, which is consistent with the evaluation results of the rock burst resistance.

Abstract Thyroid dysfunction is commonly seen in major depressive disorder (MDD), and is particularly prevalent in female patients. Moreover, gender differences occur in many aspects of MDD, including suicide attempts (SAs). We aimed to explore gender differences in the prevalence and clinical correlates of SAs in young first-episode drug-naïve MDD patients with thyroid dysfunction, which have not yet been reported. We recruited 509 patients in this study. Demographic and clinical characteristics were collected. We used HAMD-17, HAMA-14, the positive subscale of PANSS, and CGI-S to assess every participant. We found no significant difference in the prevalence of SAs between male and female subgroup. Gender differences in factors associated with SAs were found with anxiety, body mass index, serum anti-thyroid antibodies (A-TPO), and free triiodothyronine levels in male patients and anxiety, CGI-S score, and A-TPO in female patients. We found no gender differences in the prevalence of SAs; however, there were gender differences in several clinical correlates of SAs, highlighting specific strategies to avoid SAs in male and female MDD patients.

Abstract To have effective water resource management, the distributed hydrological models are commonly applied for supporting the decision‐making processes. Among different inputs, the spatial distributed rainfall plays significant role in those model simulations. Many interpolation methods have been developed for generating distributed rainfall based on measurement samples. However, depending on the catchment characteristics and data availability, the suitable interpolation algorithm is case‐dependent. This paper presents one operational approach for determining the resonable interpolation algorithm in a complex large catchment (Var catchment, France). Based on the daily rainfall data (2008–2014) collected from 16 stations in the Var catchment, six different interpolation approaches including: inverse distance weight (IDW), spline, kriging with linear and spherical semi‐variogram models and geographically weighted regression considering elevation effects and the combined impacts of elevation and distance to the sea were tested. Integrated the results of statistical and modeling assessments, the 400 m resolution distributed rainfall generated by IDW algorithm shows high preference in generating distributed rainfall in the Var catchment. Moreover, the strategy described in the article also shows promising acceptability for other catchments.

Abstract Low-loss dielectric modes are important features and functional bases of fundamental optical components in on-chip optical devices. However, dielectric near-field modes are challenging to reveal with high spatiotemporal resolution and fast direct imaging. Herein, we present a method to address this issue by applying time-resolved photoemission electron microscopy to a low-dimensional wide-bandgap semiconductor, hexagonal boron nitride (hBN). Taking a low-loss dielectric planar waveguide as a fundamental structure, static vector near-field vortices with different topological charges and the spatiotemporal evolution of waveguide modes are directly revealed. With the lowest-order vortex structure, strong nanofocusing in real space is realized, while near-vertical photoemission in momentum space and narrow spread in energy space are simultaneously observed due to the atomically flat surface of hBN and the small photoemission horizon set by the limited photon energies. Our approach provides a strategy for the realization of flat photoemission emitters.

Knowing the functions of buildings is valuable in urban planning and management. For example, it can be used for the assessment of urban planning implementation and the fine-tuning of community governance. At large scales, determining building functions can be time-consuming and laborious. While point of interest (POI) data can be used to identify urban building functions, it is prone to missing values. The present study proposes combining POIs with the spatial relationships between geographic entities and geographic information systems (GIS) to improve the accuracy of urban building function identification. First, the POIs are reclassified according to building functions. Second, the spatial relationships among road networks, buildings and POIs are analysed, and the frequency density ratios of POI types are calculated to identify the functions of buildings that contain POIs. Finally, buildings that do not contain POIs are identified by calculating the spatial similarity between unrecognised buildings and recognised buildings within the same road network mesh. The method can identify buildings with singular residential, commercial, office, and public services functions, as well as seven mixed functions, with an accuracy, recall, and F1 value of 90.28%, 97.52%, and 93.76%, respectively. Public service buildings and residential buildings have the highest identification precision, while the identification precision of mixed commercial and public service buildings and mixed residential and public service buildings are the lowest. An experiment demonstrates the effectiveness of the method. The results indicate that the spatial relationships between entities can compensate for missing POI data.

High-quality environmental perceptions are crucial for self-driving cars. Integrating multiple sensors is the predominant research direction for enhancing the accuracy and resilience of autonomous driving systems. Millimeter-wave radar has recently gained attention from the academic community owing to its unique physical properties that complement other sensing modalities, such as vision. Unlike cameras and LIDAR, millimeter-wave radar is not affected by light or weather conditions, has a high penetration capability, and can operate day and night, making it an ideal sensor for object tracking and identification. However, the longer wavelengths of millimeter-wave signals present challenges, including sparse point clouds and susceptibility to multipath effects, which limit their sensing accuracies. To enhance the object recognition capability of millimeter-wave radar, we propose a GAN-based point cloud enhancement method that converts sparse point clouds into RF images with richer semantic information, ultimately improving the accuracy of tasks such as object detection and semantic segmentation. We evaluated our method on the CARRADA and nuScenes datasets, and the experimental results demonstrate that our approach improves the object classification accuracy by 11.35% and semantic segmentation by 4.88% compared to current state-of-the-art methods.

It has been demonstrated that the results caused by abnormal levels of Cysteine (Cys) are not negligible in biological processes. Furthermore, mitochondria are one of the most important organelles, which not only produce cellular energy, but also participate in signal transmission, growth, death, and other biological processes. Therefore, developing an efficient fluorescent probe targeting mitochondria to detect Cys in cells is useful for clinic pathological diagnosis. In this report, a near-infrared (NIR) fluorescent probe LAA based on link-anthocyanin as fluorophore and acrylate as identification groups has been prepared. Link-anthocyanin, as an NIR-emitting fluorophore, showed favorable water solubility and strong fluorescence intensity. Acrylate, as a recognition site, exhibited intense sensitivity and selectivity to Cys. In addition, LAA had a high tendency to localize to mitochondria due to the lipophilic positive ion in the link-anthocyanin. Under the excitation of 560 nm, the probe LAA could detect Cys with high selectivity and low detection limit (37 nM) at the emission of 670 nm, which belonged to the NIR range and was beneficial for biological application. Furthermore, LAA exhibited great biocompatibility and low cytotoxicity, which could monitor Cys in mitochondria of living cells in real-time.

Plasmon decay via the surface or interface is a critical process for practical energy conversion and plasmonic catalysis. However, the relationship between plasmon damping and the coupling between the plasmon and 2D materials is still unclear. The spectral splitting due to plasmon–exciton interaction impedes the conventional single‐particle method to evaluate the plasmon damping rate by spectral linewidth. The interaction between a single gold nanorod and 2D materials using the single‐particle spectroscopy technique assisted with in situ nanomanipulation is investigated. The approach allows to indisputably identify that the plasmon–exciton coupling would induce plasmon damping in the GNR–WSe2 hybrid. It is confirmed that the resonant energy transfer channel dominates the plasmon decay rather than the charge transfer channel in the GNR–graphene hybrid first. The contribution of the charge transfer channel by using thin hBN layers as an intermediate medium to block the charge transfer is excluded. It is also found that the contact layer between the GNR and 2D materials contributes most of the interfacial plasmon damping. These findings contribute to a deep understanding of interfacial excitonic effects on the plasmon and 2D materials hybrid.

Resolving the photonic modes in real space is essential to understand the fundamental process and control of photonic behavior in optoelectric devices. However, the understanding of the photonic modes of semimetal Cd3As2 is still lacking. Herein, the quasicylindrical waves (QCW) on Cd3As2 nanoplates using photoemission electron microscopy (PEEM) are found out. The QCW is due to the optical field scattered by subwavelength indentations, with wavelength being the same as the incident light, and their amplitude decays as r−1/2 from the edges. The transverse magnetic (TM) mode dominates the observed QCW of Cd3As2 nanoplates, which is affected by the edge structure. In broadband from UV to visible, the QCWs on Cd3As2 nanoplates are observed. Further, nanostructures to achieve subwavelength focusing and interference lattice of the Cd3As2 optical QCW are achieved. These findings demonstrate the regulation of QCW, which benefits optimizing the optoelectronic performances of semimetal materials in the future.

Heterostructures can reveal interesting and unexplored physics at the material interface. Here, the authors use time-resolved photoemission electron microscopy to investigate the photoexcited electron dynamics at a heterostructure interface composed of two polytypes of MoTe2.

Here, the authors report large photothermal nonlinearity mediated by anapole states within subwavelength Si nanodisks, offering a mechanism for dynamic tuning of far-field radiation from multipolar modes. Nonlinear scattering is used to demonstrate the potential for far-field optical localization of Si nanostructures.

This paper presents a 0.25-scale quasi-three-dimensional hydraulic model experiment of transient fluid flow phenomena during continuous casting of steel under solidification. Water cooling is performed at the bottom of the mold, and saturated sodium acetate solution is covered on the spring and particle arrangement at the bottom of the mold/on the dummy bar to simulate the solidification phenomenon in the actual continuous casting process. The results show that the solidification on the dummy bar surface is very important to the early stage of the filling process and cannot be ignored. Its influence gradually decreases with the rise of the liquid level, and basically disappears when the liquid level rises to a certain height (steady liquid level, SLL). In SLL, the interface morphology of the solidified layer is more affected by the flow, while the interface morphology of the solidified layer has no significant effect on the liquid surface velocity.

Recognizing building group patterns is fundamental to numerous fields, such as urban landscape evaluation, social analysis, and map generalization. Despite the increasing number of algorithms available for building group pattern recognition, there is still a lack of satisfactory grouping results due to insufficient information and only geometric features being provided to recognition methods. This study aims to provide a novel building grouping method that combines building function and geometric information. We specifically focus on the process of recognizing building groups in topographic maps as a prerequisite to subsequent map generalization. First, the building functions are inferred using the dynamic time warping (DTW) algorithm based on Tencent user density data and POIs (points of interest). Then, two types of constrained Delaunay triangulations (CDTs) are created for each building block, from which several spatial indices, such as the continuity index (SCI), direction, and distance of every two adjacent buildings, are derived. Finally, each building block is modeled as a graph on the grounds of derived matrices and building function information, and a graph segmentation approach is proposed to extract building groups. A case study is conducted to test the proposed approach. The experimental results indicate that the proposed approach can produce satisfactory results, given that the correctness value is above 81.63% for our study area. Comparative studies reveal that the method without building function information is an ineffective grouping method when buildings with different functions are close to each other. In addition, generalization results derived from the proposed method are more in line with those of maps for daily use, as they provide users with more accurate spatial divisions of urban buildings.

Building pattern recognition is fundamental to a wide range of downstream applications, such as urban landscape evaluation, social analyses, and map generalization. Although many studies have been conducted, there is still a lack of satisfactory results, due to the imprecision of the relative direction model of any two adjacent buildings and the ineffective extraction methods. This study aims to provide an alternative for quantifying the direction and the spatial continuity of any two buildings on the basis of the Delaunay triangulation for the recognition of linear building patterns. First, constrained Delaunay triangulations (CDTs) are created for all buildings within each block and every two adjacent buildings. Then, the spatial continuity index (SCI), the direction index (DI), and other spatial relations (e.g., distance) of every two adjacent buildings are derived using the CDT. Finally, the building block is modelled as a graph based on derived matrices, and a graph segmentation approach is proposed to extract linear building patterns. In the segmentation process, the edges of the graph are removed first, according to the global thresholds of the SCI and distance, and are subsequently subdivided into subgraphs on direction rules. The proposed method is tested using three datasets. The experimental results suggest that the proposed method can recognize both collinear and curvilinear building patterns, given that the correctness values are all above 92% for the three study areas. The results also demonstrate that the novel SCI can effectively filter many insignificant neighbor relationships in the graph segmentation process. It is noteworthy that the proposed DI is capable of measuring building relative directions accurately and works efficiently in linear building pattern extraction.

Light emission from gold nanoparticles was investigated with ultra-narrow-band notch filters to obtain the complete spectral shape. The anti-Stokes emission band was observed at all excitation wavelengths. The spectral shape of the anti-Stokes emission could be well fitted by a Fermi–Dirac-like line shape, while the spectral profile of the Stokes emission could be fitted by a Lorentzian line shape. The electron distribution and local surface plasmon resonance jointly determined the spectral shape. Additionally, we found that the anti-Stokes emission intensity increased more rapidly compared with that of the Stokes emission as illumination power was increased. This phenomenon can be understood from the temperature dependence of the electron distribution owing to photothermal effects.

Multi-scale object matching is the key technology for upgrading feature cascade and integrating multi-source spatial data. Considering the distinctiveness of data at different scales, the present study selects residential areas in a multi-scale database as research objects and focuses on characteristic similarities. This study adopts the method of merging with no simplification, clarifies all the matching pairs that lack one-to-one relationships and places them into one-to-one matching pairs, and conducts similarity measurements on five characteristics (i.e., position, area, shape, orientation, and surroundings). The relevance vector machine (RVM) algorithm is introduced, and the method of RVM-based spatial entity matching is designed, thus avoiding the needs of weighing feature similarity and selecting matching thresholds. Moreover, the study utilizes the active learning approach to select the most effective sample for classification, which reduces the manual work of labeling samples. By means of 1:5000 and 1:25,000 residential areas matching experiments, it is shown that the RVM method could achieve high matching precision, which can be used to accurately recognize 1:1, 1:m, and m:n matching relations, thus improving automation and the intelligence level of geographical spatial data management.

Intrinsic luminescence from metal nanostructures complements conventional scattering and absorption behaviors and has many interesting and unique features. This phenomenon has attracted considerable research attention in recent years because of its various potential applications. In this review, we discuss recent advances in this field, summarize potential applications for this type of luminescence, and compare theoretical models to describe the phenomena. On the basis of the excitation process, the characteristic features and corresponding applications are summarized briefly in three parts, namely, continuous-wave light, pulsed laser, and electron excitation. A universal physical mechanism likely operates in all these emission processes regardless of differences in the excitation processes; however, there remains some debate surrounding the details of the theoretical model. Further insight into these luminescence phenomena will not only provide a deeper fundamental understanding of plasmonic nanostructures but will also advance and extend their applications. [ABSTRACT FROM AUTHOR]