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In coal mining environments with complex topographic and geological conditions, the presence of primary cracks in the rock strata of the upper mining airspace is critical to mine safety, especially when roof slabs are broken. Cracked roof slabs not only increase risks during mining but also make mining operations more challenging. Therefore, studying the initial damage state of the roof rock formation is great significance. In this study, the effects of different prefabricated crack sizes and inclination angles on the mechanical properties of the coal-rock composite containing cracks were analyzed through the uniaxial compression experiments and PFC2D numerical simulations. The results show that the peak strength and elastic modulus of the coal-rock composites fall between those of pure coal and sandstone, while the macroscopic mechanical parameters of crack-containing composites are significantly lower than those of non-crack-containing composites. Coal-rock composites with different crack characteristics exhibited different mechanical properties, with their damage modes were caused by the combined effects of tensile and shear damage. The increase in crack inclination altered the crack extension path, and the final damage of the specimen manifested first in the upper part, then the middle part, and ultimately in the lower part of the coal body, with tension-induced bulk damage being the dominant failure mode. Analysis of the radial cumulative map revealed that cracks primarily extended along 90° and 270° directions, indicating a strong tendency for crack propagation under axial pressure. The damage evolution curves indicate a nonlinear relationship between the damage factor and strain. While increased crack inclination enhances the compressive performance of coal-rock composites, it simultaneously accelerates structural destabilization. These findings offer theoretical insights into the damage mechanisms of coal-rock composites with cracks, serving as valuable references for coal mining safety. [ABSTRACT FROM AUTHOR]

Despite ample research on the association between the availability of flexible working arrangements (FWAs) and satisfaction from an individual perspective, little has explored the dyadic correlation between the availability of FWAs and satisfaction with work-life flexibility (WLF) from a couple-level perspective among working parents. Drawing on a linked lives perspective and the work-family border theory, this study contributes to the literature by adopting the longitudinal couple-level dyadic data from the Household, Income, and Labour Dynamics in Australia (HILDA) survey (2001–2021) to examine how couples' availability of FWAs affects their own and their spouses' satisfaction with WLF among working parents. The results show that among couples with children, mothers' availability of FWAs significantly improves their own and their husbands' satisfaction with WLF. In contrast, fathers' access to FWAs only improves their own satisfaction with WLF. Moreover, the impact of one's availability of FWAs on their satisfaction with WLF, as well as the effects of mothers' availability of FWAs on their husbands' satisfaction, are more pronounced among formal contract workers. Overall, this study underscores the dyadic association between couples' FWAs and satisfaction with WLF among working parents, delineating an asymmetric dynamic. [ABSTRACT FROM AUTHOR]

BACKGROUND: The Southern rice black‐streaked dwarf virus (SRBSDV) transmitted by Sogatella furcifera constitutes a threat to sustainable rice production. However, most rice varieties are highly vulnerable to SRBSDV, whereas the occurrence of the viral disease varies significantly under field conditions. This study aimed to evaluate the potential of rice varietal resistance to S. furcifera in reducing SRBSDV transmission. RESULTS: Among the five rice varieties, Zhongzheyou8 and Deyou108 exhibited high resistance to S. furcifera, Baixiangnuo33 was susceptible, and TN1 and Diantun502 were highly susceptible. The S. furcifera generally showed non‐preference for and low feeding on the Zhongzheyou8 and Deyou108 plants, which may explain the resistance of these varieties to S. furcifera. Transmission of SRBSDV by S. furcifera was significantly impaired on the resistant varieties, both inoculation and acquisition rates were much lower on Zhongzheyou8 than on TN1. The short durations of S. furcifera salivation and phloem‐related activities and the low S. furcifera feeding amount may explain the reduced SRBSDV inoculation and acquisition rates associated with Zhongzheyou8. Spearman's rank correlation revealed a significant negative correlation between S. furcifera resistance and SRBSDV transmission among the tested varieties. CONCLUSION: The results indicate that rice varietal resistance to the vector S. furcifera hinders SRBSDV transmission, which is largely associated with the host plant selection and feeding behaviors of the vector. The current findings shed light on the management of the SRBSDV viral disease through incorporation of S. furcifera resistant rice varieties in the management protocol. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The transmission of plant viruses is closely associated with the specific probing behaviors of the vectors. Pymetrozine is a pyridine azomethine insecticide that interferes with nervous regulation of feeding behavior of piercing‐sucking insects. This study aimed to evaluate the potential of sublethal concentrations of pymetrozine in reducing the transmission of Southern rice black‐streaked dwarf virus (SRBSDV) by the planthopper Sogatella furcifera. RESULTS: Laboratory assays showed that both acquisition and inoculation rates of SRBSDV decreased significantly in the planthoppers feeding on plants treated with lethal concentrations 10% and 50% (LC10 and LC50) pymetrozine compared with the insects feeding on the control plants, for which significant effects of pymetrozine concentration and time post‐treatment were detected. Honeydew excretion of the planthoppers showed significant reduction with increasing concentration of the insecticide but no significant association with time post‐treatment. Electrical penetration graph recordings revealed that total durations of each waveform in both acquisition and inoculation were significantly affected by pymetrozine treatment, with total durations of non‐probing (NP), penetration initiation (N1), and extracellular activity (N3) elongated whereas those of salivation (N2) and phloem‐related activities (N4‐a and N4‐b) shortened. Additionally, both acquisition and inoculation rates were significantly lower at 168 h than at 6 h post‐treatment. CONCLUSION: The results indicate that sublethal concentrations of pymetrozine reduce SRBSDV transmission, which is associated with reduction in feeding and alteration in probing behaviors characterized by the prolonged non‐probing, penetration initiation and extracellular activity and shortened salivation and phloem‐related activities. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]