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K-feldspar–quartz vein-type Au deposits, represented by the Hadamengou super-large Au deposit, are widely developed in the Archean high-grade metamorphic terrane in the western segment of the northern margin of the North China Craton. However, the formation processes of these Au deposits have long been debated, and their genetic relationship with magmatic activity remains unclear. In this study, by examining the geological and geochemical characteristics of the Hadamengou Au deposit and several related intrusions, we find that the Au–(Mo) mineralization system may be related to Indosinian alkaline magmatic activity. The Dongshadegai and Xishadegai intrusions, which are related to the formation of the Hadamengou Au deposit, formed in an Indosinian extensional tectonic environment, and both are characterized by high silica and alkaline contents and strong oxidizing properties, indicating that the parent magmas of these intrusions were capable of dissolving and transporting metallic elements during magma formation and evolution. The Indosinian Hadamengou Au deposit contains minerals such as magnetite and barite, and the H, O, S and Pb isotopic characteristics of this deposit indicate that the ore-forming fluids originated from magmatic–hydrothermal fluids and had oxidizing properties. These observations suggest the presence of an oxidized intrusion-related Au–(Mo) mineralization system in the studied metamorphic terrane. [ABSTRACT FROM AUTHOR]

Three NE-striking zoned polymetallic ore districts were found at the transition between the Shanhaiguan-Beizhen paleo-uplift and the Liaoxi depression at the midway point of the northern margin of the North China Plate. Although these deposits are located proximal to one another, they are metallogenic different and closely associated with the granite intrusions, and Au, Pb-Zn, and Mo are the major ore-forming elements. This paper investigates the rock/ore rare earth elements and trace elements and part of the whole-rock major elements of the Wenzhangzi Au-polymetallic deposit in western Liaoning Province. The results indicate that the andesite, granodiorite, and Au-rich polymetallic ore-forming fluids in the deposits exhibit the same crustal origin and closely associated with the Archean Au-rich crystalline basement. Granodiorite in the area tends to show a transition from quasi-aluminous to peraluminous → S-type granite, whereas the closely associated granite in the Yangjiazhangzi-Lanjiagou Mo metallogenic district is a differentiated I-type granite. These granites differ in age, with the former emplacing during the Mesozoic tectonic regime transition period and the latter emplacing during the intra-plate extrusion-uplift orogeny. [ABSTRACT FROM AUTHOR]

Image dehazing is a useful technique which can eliminate the bad effect of haze on images and enhance the performances of image/video processing algorithms in the hazy weather. In this study, a single image dehazing method is proposed. The authors estimate the initial transmission properly based on latent region‐segmentation and refine the estimated initial transmission by an objective function with a novel weighted L1‐norm regularisation term. The half‐quadratic splitting minimisation method is employed to solve this optimisation problem. They also define an evaluation function to estimate the reliable global atmospheric light. With the refined transmission map and atmospheric light they recover the haze‐free image by the haze imaging model. The authors' method is compared with three state‐of‐the‐art methods and is also validated by two image quality assessment methods. The comparative experimental results and evaluations demonstrate that their method can recover comparable and even better results with clear details, low contrast loss and high contrast in most cases. [ABSTRACT FROM AUTHOR]

The existence of fissures poses a serious threat to the safe production of underground mines, and this paper investigates a polymer grouting material for filling fissures in underground mines. To optimise the ratio of polymer grouting materials, this paper designed 16 test groups using the orthogonal test method to find the most reasonable slurry ratio. In order to study the gel diffusion process of polymer slurry in the fissure and to explore the changes of various parameters of the slurry after injection, simulated grouting tests were carried out, and the distribution laws of viscosity, pressure, and diffusion distance of the slurry were discussed. The findings indicate that when the proportion of ethylenediamine polypropylene oxide tetrol: glycerol polyether: catalyst: foam stabiliser is 10:8:0.5:0.4, the polymer grouting material has excellent compressive strength, and the maximum compressive strength can reach 12.31 MPa. Prior to reaching the gel time point, the viscosity of the polymer slurry was nearly constant, which is basically maintained at 0.772 Pa·s under normal temperature and pressure, but after reaching the gel time point, it abruptly rose. As the slurry mass increased, so did the penetration distance and pressure; in the simulated grouting test, when the slurry mass was 400 g, the maximum diffusion distance of the slurry reached 39 cm. Conversely, as the fracture pore size increased, the diffusion distance and pressure of the slurry decreased. Along the diffusion path, the slurry pressure progressively drops, but this change is not synchronised with the diffusion distance's change. This work can serve as a reference for the configuration of polymer slurry and aid in comprehending the diffusion law of the slurry within the fissure.

Background: Depression rates among adolescents have risen dramatically over the past decade. Therefore, preventing depression among adolescents is particularly important. Differences in lifestyle habits may play a role in depression., Purpose: This study aimed to explore the influence of living habits on depression levels among rural middle school students in Northeast China and to provide a theoretical basis for developing interventions to reduce depression levels in middle school students., Methods: A total of 296 middle school students aged 13-15 years from Benxi City, Northeast China completed the anthropometric measurements, Physical Activity Scale-3 (PARS-3), and the Self-Rating Depression Scale (SDS). Their average screen time in the most recent week, parents' education level, and monthly family income were collected through a questionnaire., Results: Females had higher depression scores than males (41.0 ± 6.9 vs. 37.9 ± 8.0). Physical activity (β = -0.38, t = -7.06, P < 0.01), family income (β = -0.20, t = -4.07, P < 0.01), screen time (β = 0.16, t = 3.34, P < 0.01), age (β = 0.15, t = 3.16, P < 0.01), sex (β = -0.13, t = -2.74, P < 0.01), and sleep quality (β = -0.08, t = -1.87, P < 0.01) are important factors related to depression levels., Conclusion: The preliminary analysis results showed that among middle school students in rural Northeast China, the depression level of females was significantly higher than that of males. Poor quality sleep, low levels of physical activity, low household income, and long screen time were positively associated with depression. Therefore, strengthening physical activity, improving sleep quality, and reducing screen time are of clinical relevance in preventing and reducing depression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhao, Wang, Xu, Yan, Wang, Wang, Liu and Hao.)