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To investigate the variations in wave velocity fields between impact and outburst coal seams, we analyzed the fluctuations in wave velocity under loading conditions for both coal types. A comprehensive methodology was developed to correct coal wave velocities in response to stress and gas presence, which was then applied to field assessments of hazardous regions. Our findings reveal significant differences in wave velocity alterations between impact and outburst coal seams during loading-induced failure. Gas pressure exhibits a negative correlation with wave velocity in outburst coal (correlation coefficient R2 = 0.86), whereas wave velocity in impact coal demonstrates a positive correlation with stress (R2 = 0.63). A robust methodology for correcting coal wave velocities in response to stress and gas presence was established to enable more accurate measurement of wave velocity changes. In field applications, seismic wave computed tomography identified stress anomalies that closelycorresponded with geological structures and mining operations, effectively pinpointing hazardous zones. The abnormal wave velocity coefficient ranges for outburst coal seams and impact coal seams are −0.6 to 0.25 and −0.35 to 0.16, respectively, which correspond well with the field stress distribution. [ABSTRACT FROM AUTHOR]

Background and Objectives: There are critical disparities in the neurosurgical care provided around the globe due to challenges in resource allocation, training, and infrastructure. Global neurosurgical collaborations have replaced classical mission trips to address these disparities. However, the development of these collaborations and the impact of research funding on their growth has not yet been systematically studied. In this article, we use a graph theoretical approach to investigate trends in funding and co-authorship between and among authors from high-income countries (HICs) and authors from low- and middle-income countries (LMICs)., Methods: A bibliometric search of the global neurosurgical literature returned 307 articles between 1985 and 2020. A connectivity analysis was conducted to compute the number of co-authorships between HIC-HIC, LMIC-HIC, and LMIC-LMIC authors. The number of connections, summarized as either a global sum of connections or an average number of connections per manuscript, were analyzed in the context of time and funding through parametric statistical tests., Results: An exponential increase in co-authorship collaboration was observed over time, especially after 2015. Notably, LMIC-LMIC collaborations appear to be rising at over twice the rate of other collaboration types. The presence of funding, in general, was associated with increased co-authorship of manuscripts by LMIC and HIC authors together (p = 0.033). A significant majority of the funding associated with LMIC-HIC co-authorships was supplied through charitable organizations and government grants (p = 0.034, p = 0.009, respectively). Most LMIC-LMIC co-authorships had no funding., Conclusion: This work shows significant and rapid growth in international neurosurgical partnerships, especially in HIC-LMIC and LMIC-LMIC collaborations. Also, a significant positive relationship exists between research funding and LMIC-HIC co-authorship trends. This work encourages us as a community to continue to expand our translational collaborations with LMIC neurosurgeons and establish funding mechanisms independent of HIC authors., (Copyright © 2024 Elsevier Inc. All rights reserved.)