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Caving mining in extra-thick coal seams induces large-scale overburden movement, leading to more intense fracture processes in key strata, more significant surface subsidence, and frequent dynamic disasters in mines. This study, using the N34-2 caving face of the 17th coal seam at Junde Mine as a case study, aims to investigate the time-varying linkage mechanism between surface subsidence, microseismic characteristics, and fracture scales of the overburden’s key strata under such mining conditions. Based on Timoshenko’s theory, a bearing fracture mode for the overburden’s key strata is proposed, and corresponding fracture criteria are established. The fracture modes and step distances of the N34-2 working face were calculated theoretically and verified using microseismic localization data, showing that higher key strata are more prone to bearing failure, leading to a significant increase in fracture step distances. Numerical simulations and surface monitoring techniques were employed to comprehensively analyze the main controlling factors for surface subsidence. To further clarify the linkage mechanism between the fracture of high-position key strata and surface subsidence, the full fracture cycle under extra-thick coal seam caving mining is divided into four sub-processes: short-term fracture, rapid movement, compaction stability, and energy accumulation. The dynamic relationship between overburden movement, microseismic data, and surface subsidence responses is analyzed for each sub-process, establishing a time-varying linkage system. This approach offers a more systematic and accurate method to predict and assess the overburden movement and fracture processes, providing new insights for the prevention and control of rock burst disasters in extra-thick coal seams.

Potato common scab is one of the major diseases posing a threat to potato production on a global scale. No chemical agents have been found to effectively control the occurrence of this disease, and research on the identification of resistance genes and the development of molecular markers remains relatively limited. In this study, a diploid potato variety H535, which exhibits resistance to the predominant pathogen Streptomyces scabies, was utilized as the male parent, whereas the susceptible diploid potato variety H012 served as the female parent. Building upon the resistance QTL intervals pinpointed through a genome-wide association study, two potential resistance loci were localized on chromosome 2 of the potato genome, spanning the regions between 38–38.6 Mb and 41.3–42.7 Mb. These intervals accounted for 18.03% of the total phenotypic variance and are presumed to be the primary QTLs underlying scab resistance. Building upon this foundation, we expanded the hybrid progeny population, conducted resistance assessments, selected individuals with extreme phenotypes, developed molecular markers, and conducted fine mapping of the resistance gene. A phenotypic evaluation of scab resistance was carried out using a pot-based inoculation test on 175 potato hybrid progenies to characterize the F1 generation population. Twenty lines exhibiting high resistance and thirty lines displaying high susceptibility were selected for investigations. Within the preliminary mapping interval on potato chromosome 2 (spanning 38–43 Mb), a total of 214 SSR (Simple Sequence Repeat) and 133 InDel (Insertion/Deletion) primer pairs were designed. Initial screening with parental lines identified 18 polymorphic markers (8 SSR and 10 InDel) that demonstrated stable segregation patterns. Validation using bulked segregant analysis revealed that 3 SSR markers (with 70–90% linkage) and 6 InDel markers (with 70–90% linkage) exhibited significant co-segregation with the resistance trait. A high-density genetic linkage map spanning 104.59 cm was constructed using 18 polymorphic markers, with an average marker spacing of 5.81 cm. Through linkage analysis, the resistance locus was precisely mapped to a 767 kb interval (41.33–42.09 Mb) on potato chromosome 2, flanked by SSR-2-9 and InDel-3-9. Within this refined interval, four candidate disease resistance genes were identified: RHC02H2G2507, RHC02H2G2515, PGSC0003DMG400030643, and PGSC0003DMG400030661. This study offers novel insights into the genetic architecture underlying scab resistance in potato. The high-resolution mapping results and characterized markers will facilitate marker-assisted selection (MAS) in disease resistance breeding programs, providing an efficient strategy for developing cultivars with enhanced resistance to Streptomyces scabies.

To study the failure mechanism and energy dissipation law of fissured coal in different tectonic stress areas, the No.9 coal seam of the Limin coal mine was taken as the research background. The hollow inclusion stress relief method is used to measure the in-situ stress, reveal the distribution law of mine in-situ stress, and divide it into different tectonic stress areas. The UDEC numerical simulation software was used to analyze and study the failure mechanisms and energy dissipation characteristics of coal containing single fissures with different dip angles in high stress areas and stress gradient areas. The results show that: ① When in the same stress area, the stress concentration area at the end of the fissure dip angle 45° is the largest, and the macroscopic mechanical properties are the worst. The fissure dip angle is deflected from 45° to both sides, and the stress transfer effect and macroscopic mechanical properties are gradually improved. When it reaches 0° and 90°, the stress distribution of coal is the most uniform and the macroscopic mechanical properties are the strongest. With the increase of the fissure dip angle, the total energy and elastic strain energy of the system decrease first and then increase. The greater the fissure dip angle, the more severe the fissure damage inside the coal, which leads to the weakening of the total energy of the system and the strengthening of the dissipation capacity. ② When the fissure dip angle is the same, with the increase of stress level, the stress around the coal fissure in the high stress area is larger than that in the stress gradient area, and the stress concentration area at the fracture end is also larger, which is more prone to shear dilatancy and form dilatancy effect. At the same time, the total energy of the system gradually increases with the increase of the stress level, and the coal is prone to energy accumulation, which aggravates the occurrence of dynamic disasters.

Background Aridity acts as a strong environmental filter for plants and is predicted to intensify in the future, resulting in changes to leaf functional traits. However, few studies explore how interactions of multiple traits result in leaf trait tradeoff strategies along an aridity gradient, and whether trait separation occurs with increasing aridity intensity. This study examines the impact of long-term aridity on 14 plant leaf traits in two arid areas (arid and hyper-arid) in the Hexi Corridor, China. A leaf trait network (LTN) was constructed to study how leaf trait tradeoff strategies differ between the two areas. Structural equation modeling (SEM) was used to identify the direct and indirect effects of aridity and functional diversity (as measured by community weighted means and functional dispersion) on leaf nutrient concentration. Results LTN shows trait separation, poor synergy among traits, and low resource utilization. Correlation analyses showed that the mass ratio hypothesis is dominant, and aridity is positively correlated with leaf relative water content (RWC) and leaf phosphorus content, and negatively correlated with leaf nitrogen content (LNC). SEM results indicated that LNC is directly affected by aridity, RWC, leaf carbon content, and plant height. Aridity and functional dispersion directly affects leaf phosphorus content. Conclusions Results indicate that increasing drought weakens plant coordination among specific traits, and the main change in plant trait tradeoff strategies is reflected in the separation of nutrient traits. Exploring the change of the tradeoff among traits along the aridity gradient can better understand the adaptation process of plants to aridity and the process of community function change.

The biological significance of a known normal and cancer stem cell marker CD133 remains elusive. We now demonstrate that the phosphorylation of tyrosine-828 residue in CD133 C-terminal cytoplasmic domain mediates direct interaction between CD133 and phosphoinositide 3-kinase (PI3K) 85 kDa regulatory subunit (p85), resulting in preferential activation of PI3K/protein kinase B (Akt) pathway in glioma stem cell (GSC) relative to matched nonstem cell. CD133 knockdown potently inhibits the activity of PI3K/Akt pathway with an accompanying reduction in the self-renewal and tumorigenicity of GSC. The inhibitory effects of CD133 knockdown could be completely rescued by expression of WT CD 133, but not its p85-binding deficient Y828F mutant. Analysis of glioma samples reveals that CD133 Y828 phosphorylation level is correlated with histopathological grade and overlaps with Akt activation. Our results identify the CD133/PI3K/Akt signaling axis, exploring the fundamental role of CD133 in glioma stem cell behavior.

Orbit accuracy of the transfer orbit and the mission orbit is the basis for the orbit control of all-electric-propulsion Geostationary Orbit (GEO) satellites. Global Navigation Satellite System (GNSS) simulation data are used to analyze the main factors affecting GEO satellite orbit prediction accuracy under the no-thrust condition, and an electric propulsion calibration algorithm is designed to analyze the orbit determination and prediction accuracy under the thrust condition. The calculation results show that the orbit determination accuracy of mission orbit and transfer orbit without thrust is better than 10 m using onboard GNSS technology. The calibration accuracy of electric thrust is about 10−9 m/s2 and 10−7 m/s2 with 40 h and 16 h arc length, respectively, using the satellite self-positioning data of 100 m accuracy to calibrate the electric thrust. If satellite self-positioning data accuracy is at the 10 m level, the electric thrust calibration accuracy can be improved by about one order of magnitude, and the 14-day prediction accuracy of the transfer orbit with thrust is better than 1 km.

H1.6Mn1.6O4 lithium-ion screen adsorbents were synthesized by soft chemical synthesis and solid phase calcination and then applied to the recovery of metal Li and Co from waste cathode materials of a lithium cobalt oxide-based battery. The leaching experiments of cobalt and lithium from cathode materials by a citrate hydrogen peroxide system and tartaric acid system were investigated. The experimental results showed that under the citrate hydrogen peroxide system, when the temperature was 90 °C, the rotation speed was 600 r·min−1 and the solid–liquid ratio was 10 g·1 L−1, the leaching rate of Co and Li could reach 86.21% and 96.9%, respectively. Under the tartaric acid system, the leaching rates of Co and Li were 90.34% and 92.47%, respectively, under the previous operating conditions. The adsorption results of the lithium-ion screen showed that the adsorbents were highly selective for Li+, and the maximum adsorption capacities were 38.05 mg·g−1. In the process of lithium removal, the dissolution rate of lithium was about 91%, and the results of multiple cycles showed that the stability of the adsorbent was high. The recovery results showed that the purity of LiCl, Li2CO3 and CoCl2 crystals could reach 93%, 99.59% and 87.9%, respectively. LiCoO2 was regenerated by the sol–gel method. XRD results showed that the regenerated LiCoO2 had the advantages of higher crystallinity and less impurity.

Q345 steel pipe is a commonly used welding material. Whether it is shipbuilding, boiler pressure vessel or construction engineering, the demand for Q345 steel is very large. In this paper, the numerical simulation of Q345 steel pipe is carried out. It is analyzed whether the temperature field and stress field of the welded joint are similar to the reality under the condition of two-layer weld seam, so as to prove that the welding process can be implemented accordingly.

In this paper, a novel ring-down suppression system based on transfer function is proposed for the first time to suppress the ring-down time and decrease the blind area of PMUTs (Piezoelectric Micromachined Ultrasonic Transducers). This suppression system includes a transfer function and a simple P (proportion) controller, which can reduce the ring-down time without degrading any performances of PMUTs. The transfer function serves as a virtual PMUT device, feeding its output into the P controller; then, the P controller generates a suppression signal to the actual PMUT device. The ring-down time of a 115-kHz PMUT array is demonstrated to be reduced by up to 93% through the suppression system. In addition, the P controller has been experimentally optimized, reducing the blind area of the PMUT array by about 40%. Moreover, a low ring-down PMUTs system design guideline is established, which is practical and straightforward for industrial scenarios. Finally, the system can be easily integrated into ASIC (Application Specific Integrated Circuit).

Background Sarcopenia is a syndrome that occurs in older adults, marked by progressive deterioration in muscle mass, strength, and/or functional capacity. Abnormal lipid metabolism has been associated with a higher prevalence of sarcopenia, but evidence regarding the association between the Castelli Risk Index-I (CRI-I) and sarcopenia is still insufficient. The research was designed to assess the association between CRI-I and sarcopenia status among the Chinese population and to determine its incremental discriminative value within a machine learning model. Methods This research utilized information from the 2011 CHARLS survey wave. CRI-I was categorized into quartiles and its association with sarcopenia was evaluated through logistic regression and restricted cubic splines (RCS). Seven candidate models were developed using the 2011 data, and the optimal model was identified, followed by temporal external validation with the 2015 CHARLS wave. To assess the additional discriminative value of CRI-I, we evaluated model performance using receiver operating characteristic (ROC) curves, precision-recall curves (PRC), calibration plots, and decision curve analysis (DCA). Finally, the SHapley Additive exPlanations (SHAP) algorithm was used to show the importance of each feature. Results A total of 1,332 individuals (15.1%) met the diagnostic criteria for sarcopenia. After full adjustment, higher CRI-I levels were associated with progressively lower odds of sarcopenia. RCS analysis further demonstrated that the association exhibited a non-linear pattern. Incorporating CRI-I into the optimal model improved discriminative performance. The model also demonstrated good calibration and clinical utility. Additionally, the SHAP algorithm was applied to calculate feature importance for the model’s estimated probability of having sarcopenia, which identified age as the most important feature, followed by CRI-I. Conclusions CRI-I showed superior discriminative performance for sarcopenia compared with six other non-traditional lipid indices. Elevated CRI-I levels correlated with substantially reduced sarcopenia likelihood. Adding CRI-I to the model improved probability stratification and may help identify individuals more likely to have sarcopenia.