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To understand the roles of charcoal and ectomycorrhizal fungi (ECMF) on tree growth, which relates to the rehabilitation of forest ecosystems after forest fires, two experiments were set up in this study, the first was to determine the correct amount of charcoal for Japanese larch (Larix kaempferi Sarg.) seedling growth by applying oak charcoal to basic soil medium at ratios of 1:1, 1:2, 1:4 and 1:8 by volume. The second experiment investigated the combined effects of four types of charcoal: derived from oak wood, husks of buckwheat, rice and activated charcoal of larch wood, and two types of ECMF: Pt (Pisolithus tinctorius Pers.) and Ec (Pt + Rhizopogon spp. + Laccaria spp. + Scleroderma spp.) on the growth of Japanese larch seedlings. Our results show that growth was significantly stressed by large amounts charcoal applications. There were significant variations among the four types of charcoal on growth. We concluded that the addition of charcoal was the critical factor that influenced larch growth and ECMF formation. Rice charcoal and Ec stimulates the growth and nitrogen uptake of Japanese larch seedlings, thus the most suitable fungus and charcoal for practices is Ec-rice charcoal (1: 8 charcoal to basic soil). [ABSTRACT FROM AUTHOR]

Laying long horizontal borehole (LHB) in mining‐induced strata fractures for coal‐bed gas drainage in the goaf is a pivotal method for eliminating safety hazards, preventing atmospheric pollution, and realizing gas utilization. A crucial premise of this method is to determine the effective drainage range of the borehole, a key parameter directly affecting boreholes spacing and drainage efficiency. In this study, a model of gas seepage during LHB drainage within a circular equipotential boundary was presented, and the complex variable function theory and the mirror principle were adopted for deriving the complex potential function of gas flow under the condition of LHB drainage and the drainage volume function of a single center borehole. Besides, the main indicator to determinate the effective drainage range of LHB was given. Specifically, the indicator refers to the distance between the turning point (the point at which the change rate of the gas flow velocity is −0.002 around the borehole) and the center of the borehole. Subsequently, numerical simulation was conducted to obtain the effective drainage range of LHB within mining‐induced fractures of overlying strata, that is, 4 m < r < 7 m. Furthermore, discussion of the effective drainage range of LHB was carried out by analyzing gas flow velocity distributions and LHB drainage volumes. A case study demonstrates that a double‐borehole layout with a 10 m spacing can effectively control pressure‐relief gas in the goaf. Meanwhile, such a layout can achieve well‐balanced drainage efficiency of each borehole with a minimal difference of 0.31 m3 min−1, which is only about 7.9% of the average drainage volume of the two boreholes. The above results verify that the determined effective drainage range of LHB is reasonable. The research results can provide references for determining the drainage range of LHB in multi‐borehole layout of coal mines, and then determining the spacing of LHBs arrangement, thereby improving the efficiency of gas extraction. [ABSTRACT FROM AUTHOR]

Autonomous vehicles require more precise and reliable braking control, and electro-hydraulic braking (EHB) systems are better adapted to the development of autonomous driving. However, EHB systems inevitably suffer from unilateral dead zone nonlinearity, which adversely affects the position tracking control. Therefore, a finite-time adaptive control strategy was designed for unilateral dead zone nonlinearity. Initially, the unilateral dead zone nonlinearity was reformulated into a matched disturbance term and an unmatched disturbance term to reduce the adverse effects of disturbances, thereby enhancing system controllability. Then, the "complexity explosion" in the design of the control strategy was avoided by command filtering, and the design process of the controller was simplified. Furthermore, the finite-time control theory was employed to boost the system's convergence speed, thereby enhancing control performance. In order to ensure the stability of the system under the dead zone disturbance, the unknown disturbance terms were estimated. The stability of the control strategy was validated through the finite-time stability theorem and the Lyapunov function. Eventually, simulations and hardware-in-the-loop (HIL) experiments validated the feasibility and availability of the finite-time adaptive control strategy. [ABSTRACT FROM AUTHOR]

Failure of any of the drive systems in a Four-Wheel Independent Drive (4WID) electric vehicle may affect the control performance and driving safety of the whole vehicle. Therefore, in this paper, a fault-tolerant controller (FTC) for 4WID electric vehicles considering drive actuator failures is proposed. First, a comprehensive characterization of multiple fault types is achieved by establishing a generalized fault model and designing a comprehensive fault factor. Second, based on the comprehensive fault factor, an LPV model with faults is constructed. Further, a fault-tolerant controller based on LPV/H∞ output feedback is designed by combining the weighting function. Finally, the effectiveness of the FTC in this paper is verified by simulation and hardware-in-the-loop (HIL) experiments. The experimental results show that the FTC designed in this paper can improve the stability of the vehicle traveling while ensuring tracking accuracy when the drive system fails. [ABSTRACT FROM AUTHOR]

The gases released by underground coal mining pose a threat to mine safety, lead to resource wastage, and contribute to environmental pollution. Employing long horizontal boreholes (LHB) for gas extraction proves to be an effective solution. However, accurately determining the LHB's position within the overlying rock strata is challenging due to complex mining and geological conditions. This study introduces a novel "zone‐position" method for identifying the optimal LHB placement, utilizing both physical simulation tests and theoretical analysis. The approach comprises two steps. Initially, it identifies the appropriate LHB layout zone within the overlying strata. It delineates four subzones within the fractured zone, among which the stable fractured subzone (SFSZ) is identified as the most favorable for LHB placement. The boundaries of the SFSZ are also defined. Subsequently, the method focuses on pinpointing the LHB's precise location within the SFSZ, proposing a criterion that considers gas accumulation, strata permeability, and LHB stability. Application of this method in engineering projects demonstrates that the gas extracted by LHBs accounts for about 60% of the total gas emission. Furthermore, the volume of gas extracted at the optimal LHB location reaches up to 5.52 m3 min−1, triple that of other locations. [ABSTRACT FROM AUTHOR]

Improving the resolution of seismic migration images plays an important role for geophysical interpreters to characterize underground reservoirs. However, the classical image domain least‐squares migration method based on the local‐stationary assumption cannot obtain a satisfactory high‐resolution seismic image due to the significant spatial variant characteristics of the point spread function. To mitigate this problem, we proposed a high‐resolution point spread function deconvolution method and applied it to two‐dimensional cases. Nevertheless, extending the two‐dimensional method to three‐dimensional problems directly would fail due to the intrinsic complexity in three‐dimensional cases. In this study, we resolve the differences encountered in the point spread function deconvolution method for two‐ and three‐dimensional cases and provide specific strategies for achieving high‐resolution imaging with low computational cost when extending the point spread function deconvolution method to three‐dimensional cases. The main schemes include (1) incorporating the analytical expression of the point spread function to guide the generation of three‐dimensional point spread function distributions, (2) extending the point spread function filter calculation method from a two‐dimensional square to a three‐dimensional rectangular prism and (3) interpolating to obtain more compact point spread functions for reducing migration artefacts. Results from the three‐dimensional synthetic Overthrust model and field data set demonstrate that our techniques could effectively enhance the spatial resolution of the migration images with reduced migration artefacts. With these specific strategies, the space‐variant point spread function deconvolution algorithm shows superior performance on three‐dimensional cases at a much lower computational cost compared with the classical least‐squares migration method and the local‐stationary deblurring method. Synthetic tests and real data applications confirm that the space‐variant point spread function deconvolution method has distinct advantages over both two‐ and three‐dimensional problems and can be widely adopted in practice. [ABSTRACT FROM AUTHOR]

Although orthorhombic GeSe is predicted to have an ultrahigh figure of merit, ZT ≈ 2.5, up to now, the highest experimental value is ≈0.2 due to the low carrier concentration (nH ≈ 1018 cm−3). Improving symmetry is an effective approach for enhancing the ZT of GeSe‐based materials. With Te‐alloying, Ge4Se3Te displays the two‐dimensional hexagonal structure and high nH ≈ 1.23 × 1021 cm−3. Interestingly, Ge4Se3Te transformed from the hexagonal into the rhombohedral phase with only ≈2% I–V–VI2‐alloying (I = Li, Na, K, Cu, Ag; V = Sb, Bi; VI = Se, Te). According to the calculated results of Ge0.82Ag0.09Bi0.09Se0.614Te0.386 single‐crystal grown via AgBiTe2‐alloying, it exhibits a higher valley degeneracy than the hexagonal Ge4Se3Te. For instance, AgBiTe2‐alloying induces a strong band convergence and band inversion effect, resulting in a significantly enhanced Seebeck coefficient and power factor with a similar nH from 17 µV K−1 and 0.63 µW cm−1 K−2 for pristine Ge4Se3Te to 124 µV K−1 and 5.97 µW cm−1 K−2 for 12%AgBiTe2‐alloyed sample, respectively. Moreover, the sharply reduced phonon velocity, nano‐domain wall structure, and strong anharmonicity lead to low lattice thermal conductivity. As a result, a record‐high average ZT ≈0.95 over 323–773 K with an excellent ZT ≈ 1.30 is achieved at 723 K. [ABSTRACT FROM AUTHOR]

With the development of safety technologies for intelligent commercial vehicles, electronic pneumatic braking systems (EBSs) have been widely used. However, EBS actuators may fail during vehicle operation and thus create safety problems. For this reason, we propose a path-tracking fault-tolerant control strategy under EBS actuator failure in intelligent commercial vehicles. First, in order to be able to characterize different types of brake actuator faults during the EBS differential braking process of a vehicle, a comprehensive fault coefficient for calculating the degree of fault is designed, and a BES generalized fault model is established. Second, the faults are introduced into the fault-tolerant controller through the comprehensive fault coefficients for braking torque calculation and braking pressure allocation. Thus, a vehicle path model with the complete fault coefficients as variable parameters is established. Then, based on the LPV system gain scheduling, a path-tracking LPV/H∞ fault-tolerant controller under EBS actuator faults in commercial vehicles is designed, which is used to solve the safety problem arising from sudden EBS actuator faults. Finally, we conducted experimental validation through hardware-in-the-loop tests. The results demonstrate that the control strategy designed in this paper redistributes the braking torque and synergizes with the steering system to enhance vehicle stability, thereby improving vehicle safety in the EBS failure mode. [ABSTRACT FROM AUTHOR]

Based on the finite element analysis and fracture toughness test data, this paper verifies the improved Ritchie-Knott-Rice (RKR) local failure criterion using 16MnDR ferritic steel for cryogenic pressure vessels. This criterion's applicability to 16MnDR was verified to verify fracture toughness's different influence factors in the ductile-to-brittle transition temperature (DBTT) region, such as specimen thickness (TST) and temperature. The results indicate that the (4δt, σ22c) criterion applies to 16MnDR steel and effectively transfers the minimum Jc value between samples of different temperatures and thickness.

A comprehensive understanding of the spatial-temporal evolution and driving forces on ecosystem services (ES) is essential for the agro-pastoral ecotone's ecological security in northern China. However, the land-use pattern (LULC) agglomeration with spatial differentiation in the pastoral and agricultural areas has been rarely concerned. Taking distinct LULC (1980–2018) in Chifeng as an example, we compared four crucial categories of ESs with InVEST. Using SEM, we further contrasted the effects of several variables on regional ES variations in pastoral-dominated (North) and agriculture-dominated (South) regions, respectively. Results revealed the conversion between forest and grassland oriented the LULC transformation in the North. In contrast, human-activitiy-oriented land tended to occupy environmentally sensitive places in the South. Similar ES variations were supplied with the North outperforming the South when soil conservation was omitted. As for the impacts of regional ES variations, the natural and LULC policies both showed positive effects, whereas the anthropogenic factors showed positive in the North, which was negative in the South. Therefore, the ecologically-maintained-dominant and ecologically-restored-dominant strategies should be separately adopted in the North and South. Our study provided appropriate regional ecological management suggestions for balancing the LULC-driven conflicts between ecological protection and regional development. [ABSTRACT FROM AUTHOR]

With the rapid development of social economy in China, the contradiction between the wide distribution of abandoned goaf and the shortage of land for engineering construction is becoming increasingly prominent. The effective utilization of coal mining subsidence areas has become an effective measure to alleviate the poverty of construction land in mining areas and promote the green transformation of mining cities. The key to the scientific utilization of abandoned goaf is the prevention and control of surface residual deformation, which depends on the formation mechanism of surface residual deformation. Based on the regularity of mining-induced surface movement and deformation under different mining sizes, it is concluded that the full mining degree of working face is the primary condition for entering the surface recession period. The trapezoidal and periodic forward movement characteristics of mining-induced overburden destruction are analyzed. The regularity of upward transmission of mining-induced fissures with overburden destruction is clarified. The influencing factors of surface residual deformation are equivalent to the influencing factors of overburden structure and caved zone. The deformation characteristics of broken rock in the caved zone under different conditions (particle size, gradation, and water content) are analyzed. It is concluded that the surface residual subsidence near the boundary of the goaf is more significant than that in the middle of the goaf. It is revealed that the overburden structure at the boundary of the goaf and the re-compaction of the caved zone is the mechanism of surface residual deformation. The characteristics of surface residual deformation in abandoned goaf have been verified by field measurement, and it is pointed out that the surface residual deformation in abandoned goaf has long-term characteristics, which provides a theoretical basis for accurate prediction of surface residual deformation and rational utilization of abandoned goaf. [ABSTRACT FROM AUTHOR]

Mining fracture is the key factor in realizing water-conservation mining, stability evaluation of coal mining subsidence areas, and accurate restoration of the surface eco-environment. To clarify, the evolution and distribution of mining fractures, based on the key strata theory and the mining degree of overburden failure, the contact state of rock stratum after overburden critical failure was analyzed, the formation mechanism of "saddle shaped" water conducting fracture zone was revealed, and the permanent mining fractures were determined to be primarily concentrated in the overburden structure at the boundary of the working face. According to the shear test of sandstone in the fracture zone, the damage degree of the rock sample was positively correlated with shear stress, and the overburden structure exhibited no instability. Based on the distribution of mining fractures, the fracture zone was divided into the original fracture, tensile fracture, structural void, and void compaction areas in the horizontal direction. The structural void area had the largest residual deformation in the goaf. A regional division method based on overburden critical failure was proposed and applied in engineering by using surface movement monitoring. The results showed that the surface subsidence near the boundary of working face was greater than that in the middle, and the residual surface deformation in the goaf was closely related to the mining time, which has long-term characteristics. The rationality of the regional division method of mining fractures was also verified. [ABSTRACT FROM AUTHOR]

As coal resources trapped under surface buildings in the Wangtaipu coal mine area impede the efficient mining of coal seams and constrain the sustainable development of coal mines, a super-high-water roadway backfill mining technique for preventing building damage was adopted. According to the control principle and theoretical calculations, an engineering design was established including the reasonable width of segment coal pillars in the working face and technical parameter design. The monitoring results after the implementation of the scheme showed that building deformation was controlled within grade I, protecting the surface buildings. A reasonable roadway design parameter was achieved, with a surface subsidence of 27 mm and horizontal deformation of 0.3 mm/m, indicating that it can ensure the safety of surface buildings from the State Bureau of Coal Industry. The practical trial can provide a reference for the extraction of coal resources under similar conditions and is vital for the sustainable development of the mining industry and economic growth. [ABSTRACT FROM AUTHOR]

A simple process of thermal oxidation and self-assembly modification was developed to fabricate a stable superhydrophobic film with controllable adhesion on titanium surface. Pure titanium plate was first heat treated in atmospheric environment at 900°C, 1000°C and 1100°C respectively for a certain time, then air cooled. The subsequent air-cooling process separated the flaky yellow oxide layer formed on titanium plate during the oxidation from the substrate and a rough titanium oxide surface with micrometer and nanometer-scale hierarchical structures was obtained. The following immersion process in N-octadecyltrichlorosilane solution endowed the surface with excellent water repellence, raised its contact angle up to 166° and reduced its slide angle as low as 2°. What's more, by controlling heat temperature and time, the surface's superhydrophobicity switched from sticky state to sliding state. Field-emission scanning electron microscopy (FE-SEM) and contact angle measurement were used to characterize the morphological features and wettability of the as-prepared surface respectively. Immersion test in corrosive liquids and abrasion test with sandpaper have a further exhibition of its chemical stability and mechanical durability. The result is meaningful to a wider range of future applications of superhydrophobic titanium surface in industry and real life. [ABSTRACT FROM AUTHOR]

In the ecologically fragile mining area of northwest China, high-intensity mining has seriously affected the aquifer and surface eco-environment. In order to better implement water-preserved mining in ecologically fragile areas, the aquifer failure characteristics should be first detected accurately; therefore, it is necessary to find a convenient and fast detection method. Based on the analysis of the basic principles and influencing factors of the magnetotelluric (MT) method, the feasibility of using the MT method to detect aquifer failure is verified by testing the mined area with MT detection and field borehole measurement. Subsequently, the failure characteristics of overburden and unconsolidated aquifers under high-intensity mining are studied by MT detection and physical simulation. By comparing the physical simulation with the field measurement from the aspects of the maximum surface subsidence, interval of periodic weighting and step cracks, the reliability of the height of the water flowing fracture zone and caving zone obtained from physical simulation is verified. The analysis from MT detection and physical simulation shows that the results of the two methods are in accord with each other, which further confirms that the MT method can be used to detect the failure of overburdened structures and aquifers. The penetrating fractures are the main channel for the downward seepage of water resources, which is caused by the "two-zone" of overburden model and located in the "dimple" shape in the apparent resistivity (AR) isogram. It can provide a reference and technical support for the corresponding new water-preserved mining technology and the construction of digital mines. [ABSTRACT FROM AUTHOR]

Coal is an important resource that has supported China's economic development. This situation is expected to continue in the immediate future. However, coal mining has also led to serious environmental disasters in some mining areas. Henan Province is one of the 14 large-scale coal bases that are planned by the Chinese state. It is located in the transitional zone between the second and third terrain ladders of China and spans two tectonic units. The geological features and ecological environmental characteristics display wide spatial variations throughout this district, which is an ecologically fragile region of stepped transition type. However, large-scale, extremely intense coal mining activities will inevitably lead to further deterioration of the already fragile ecological and geological (eco-geological) environment, which makes recovery increasingly difficult. Based on the condition of the eco-geological environment and the coal mining industry in the Henan mining area, the mechanisms by which mining-induced damage can occur were analyzed. The characteristics and status of the destruction of ground structures, land resources, water resources, the atmospheric environment, and natural ecology are discussed in this paper. Appropriate mitigation measures are proposed based on the findings. This mainly includes: management practices to prevent and mitigate damage throughout all stages of mining; adoption of mining techniques that will control damage at the source; and, the adoption of appropriate post-mining recovery technologies. The analysis of mining-induced eco-geological environmental damage and mitigation measures is of importance for the prevention of eco-geological disasters, and the promotion of efficient and environmentally sustainable exploitation of coal resources. [ABSTRACT FROM AUTHOR]

• Ecosystem services supply, demand, match degree and coordination dynamics were assessed at basin scale and county scale. • Spatially correlations between influencing factors and coupling coordination degree were investigated by mixed effects model. • Different development policies at county scale according to local dynamic of coupling coordination degree and total ES supply-demand match degree were formulated. Accurately quantifying the spatiotemporal patterns in ecosystem service (ES) 1 1 ES-Ecosystem service. supply and demand and their coupling coordination dynamics, as well as identifying the spatial heterogeneity of the influencing factors for coupling coordination degree are necessary for regional sustainable development. This study used the Ulansuhai Basin in Inner Mongolia Province of China as a case to quantify the supply, demand, and supply-demand ratio of ES (meat production, grain production, carbon storage, water yield, nitrogen purification, and phosphorus purification) from 2000 to 2020. The synthesized coefficient of ES supply (ESCI) 2 2 ESCI-Synthesized coefficient of ES supply. and demand (ESDI), 3 3 ESDI-Synthesized coefficient of ES demand. the match degree of total supply and demand (MD), 4 4 MD-Match degree of total ES supply and demand. and the coupling coordination degree (CD) 5 5 CD-Coupling coordination degree between total ES supply and demand. were taken as indices to explore the relationship between the ESCI and ESDI and the coordination relationships. A mixed effects model was used to determine the spatial heterogeneity response of CD to different influencing factors. The results showed that the total ES supply in the Ulansuhai Basin always met the demand. The area with the highest ESCI was always observed in the Urad Front Banner, while Linhe district had the highest ESDI. Although incoordination improved from mild to superior from 2000 to 2020 at the basin scale, significant spatial variations were observed at the county scale. In addition, the variation in CD was significantly correlated with population, followed by precipitation, and cropland area. The findings comprehensively explore the match and coordination between ES supply and demand, and the spatial heterogeneity of the effects of the influencing factors on CD. Our study can contribute to the formulation of future policies for regional ecological restoration and sustainable development. [ABSTRACT FROM AUTHOR]

Objective: The relevant literatures in the field of pulmonary neuroendocrine tumor were analyzed to understand the lineage, hot spots and development trends of research in this tumor., Method: The Web of Science core collection was searched for English-language literature about neuroendocrine tumors of the lung published between 2000 and 2022. CiteSpace software was imported for visualization analysis of countries, institutions, co-cited authors and co-cited journals and sorting of high-frequency keywords, as well as co-cited references and keyword co-occurrence, clustering and bursting display., Results: A total of 594 publications on neuroendocrine tumours of the lung were available, from 2000 to 2022, with an overall upward trend of annual publications in the literature. Authors or institutions from the United States, Italy, Japan and China were more active in this field, but there was little cooperation among the major countries. Co-cited references and keyword co-occurrence and cluster analysis showed that research on diagnostic instruments, pathogenesis, ectopic ACTH signs, staging and prognosis and treatment was a current research hotspot. The keyword bursts suggested that therapeutic approaches might be a key focus of future research into the field for pulmonary neuroendocrine tumors., Conclusion: Over these 20 years, research related to neuroendocrine tumors of the lung has increased in fervour, with research on diagnostic instruments, pathogenesis, ectopic ACTH signs, staging and prognosis, and treatment being the main focus of research. Therapeutic treatments may be the future research trend in this field., 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 © 2023 Guo, Hu, Xiao, Cao, Huang, Liu, An, Zhang and Zheng.)

Background: Testicular torsion is an acute scrotal disorder requiring immediate emergency treatment. Ischemic injury and reperfusion injury are important causes of oxidative stress and irreversible oxidative damage after testicular torsion. Although a large number of literatures have discussed the causes and treatment of testicular torsion, there is currently a lack of systematic exploration of the historical evolution of testicular torsion and the construction of a knowledge framework., Method: The Web of Science Core Collection was searched for studies on testicular torsion published between 2000 and 2022. The basic data of the literature were analyzed by using Excel and CiteSpace software., Result: A total of 1,007 publications on testicular torsion published were found in 64 countries between 2000 and 2022, with an increasing annual publication level. Early detection, early diagnosis and early treatment of testicular torsion had always been at the core of clinical practice, and the pathological cascade reaction of ischemic injury and ischemia-reperfusion injury after testicular torsion were also at the core of basic research. Emphasis had been placed on the development of protective drugs for ischemia and reperfusion after testicular torsion in various countries, regions and institutions., Conclusion: Over the past 20 years, the research on testicular torsion had been widely concerned. Hot topics in testicular torsion in recent years were ischemia-reperfusion injury, oxidative stress, rat, doppler ultrasonography, diagnosis and orchiectomy. This article may provide a useful resource for clinicians and basic researchers regarding testicular torsion., 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., (© 2023 Hu, Guo, Xiao, Li, Luo, Li and Zhu.)