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The accommodation of the substantial eastward crustal motion of the Bayan Har block characterizes the dynamics of faults located at the eastern Tibetan Plateau. However, uncertainties persist concerning the manner and amount of deformation distributed on these faults, with slip senses and rates constituting critical factors. In the northeastern segment of the Longmenshan thrust zone, the contentious activity and the unknown geologic slip rate present challenges. This study, focusing on the Qingchuan fault, the predominant fault within the northeastern Longmenshan, employed satellite imagery interpretation, displaced fluvial terraces surveying, displacement measurements, and chronological analysis to comprehensively characterize its fault activity. Our investigation robustly demonstrates the Qingchuan fault has been active since the late Quaternary, and is primarily marked with a pronounced dextral slip at a rate of 0.6–1.0 mm/year. By quantitatively assessing the deformation rates of the faults at the eastern Tibetan Plateau, we propose that they sufficiently accommodate the entire eastward crustal movement of the Bayan Har block; thereby no additional deformation propagates beyond the Qingchuan fault. Furthermore, we introduce a subblock model to elucidate the regional crustal deformation pattern, wherein the eastward movement of the Bayan Har block transfers to the northeastward movement of the Bikou subblock. This movement results in reverse slip patterns for the Minjiang and Huya faults, while the Beichuan and Qingchuan faults predominantly experience dextral displacements. The complex strain partitioning within the northern Longmenshan range underscores the observed variations in slip patterns across different segments of the Longmenshan thrust zone, advancing our understanding of fault behavior and the orchestration of crustal deformation in this intricate tectonic framework. Key Points: We first obtain a geologic slip rate of 0.6–1.0 mm/year for the Qingchuan fault in the northeastern segment of the Longmenshan thrust zoneThe Qingchuan fault absorbs a small amount of crustal deformation but acts as the termination structure at the eastern Tibet PlateauThe strain partitioning in the northern Longmenshan range leads to the dominantly dextral rather than reverse slip of the Qingchuan fault [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the pelvicalyceal anatomy on accessibility of reusable flexible ureteroscopy (fURS) to the lower pole calyx during retrograde intrarenal surgery (RIRS). Methods: Here, 854 patients with ureteral or kidney stones with access to a renal collecting system using reusable fURS were classified into either the accessible group, in whom the deepest lower pole calyces could be touched; and the inaccessible group, in whom the deepest lower calyces could not be touched. We measured the infundibulopelvic angle (IPA), infundibular width (IW), infundibular length (IL), and calyceal pelvic height (CPH) using retrograde pyelograms and performed intergroup comparisons. Results: The median IPA, IW, IL, and CPH in the accessible and inaccessible group were 60.5° and 45.6° (p < 0.001), 10.8 and 9.4 mm (p < 0.001), 33.2 and 36.4 mm (p < 0.001), and 25.9 and 30.9 mm (p < 0.001), respectively. IPA (OR 0.963, 95% CI 0.952–0.974, p < 0.001) and IW (OR 0.519, 95% CI 0.331–0.816, p = 0.004) were significant risk factors of renal pelvicalyceal anatomy related to the accessibility of the lower pole calyces. The cut‐off value for IPA and IW was 45.8°(p < 0.001) and 7.8 mm (p < 0.001), respectively. Conclusions: IPA < 45.8° and IW <7.8 mm were negative predictors to access the lower pole calyces when using reusable fURS during RIRS. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the efficacy of a high-power holmium laser with Moses technology (MT) for the treatment of lower pole stones during retrograde intrarenal surgery (RIRS). Methods: Herein, 305 patients with lower pole stones who underwent RIRS using a high-power holmium laser with MT were retrospectively classified into the stone-free (SF) and non-SF groups. We measured the stone burden, stone volume, stone hardness, pre- or post-operative stent placement, infundibulopelvic angle (IPA), infundibular width (IW), infundibular length (IL), and calyceal pelvic height in terms of pelvicalyceal anatomy using retrograde pyelograms and evaluated the predictive factors of postoperative SF. Results: A total of 173 (56.7%) and 229 (75.1%) patients achieved a SF status on postoperative day one and at one month, respectively. Operation time in the SF group was shorter than that in the non-SF group (51.0 vs. 74.5 min). There were no significant differences in postoperative complications between the SF and non-SF groups. Significantly predictive risk factors in postoperative SF included total stone volume (odds ratio (OR), 1.056; 95% CI, 1.015–1.099; p = 0.007), IPA (OR, 0.970; 95% CI, 0.956–0.993; p = 0.009), and IW (OR, 0.295; 95% CI, 0.121–0.718; p = 0.007). The cut-off values of stone volume, IPA, and IW were 515.2 mm3, 46.8°, and 7.75 mm, respectively. Conclusions: A high-power holmium laser with MT in lower pole stones is a valuable option for positive outcomes and patient's safety. Larger stone volume, acute IPA, and narrow IW were negative predictors related to postoperative SF status. [ABSTRACT FROM AUTHOR]

The Eastern Boundary Fault Zone of the Shonai Plain (EBFZSP), Northeast Japan is an active reverse fault zone, and its southern part is considered to have a high probability of earthquake occurrence. Also, the Aosawa Fault Zone (AFZ), categorised as a geological reverse fault, lies to the east of the EBFZSP by 3–10 km along strike, almost parallel to the EBFZSP. Therefore, the EBFZSP and its surrounding area are important in terms of their long-term earthquake occurrence potential and fault development history. After performing gravity measurements to compensate for the lack of coverage in the existing gravity database, a gravity gradient tensor analysis was applied around the EBFZSP to evaluate subsurface structural indices (dimensionality, dip angle, strike direction, and boundary indices). As a result, we conclude that the southern part of the EBFZSP appears to be at a relatively mature stage, which means that the part has both high two-dimensionality and boundary properties. On the other hand, the northern part of the EBFZSP appears to be relatively immature, which means that the northern part has both low two-dimensionality and boundary properties. A similar relationship was also found between the EBFZSP and the AFZ; that is, the former was immature, and the latter was mature. These features suggest that the EBFZSP developed from the south to the north, and was derived from the AFZ. We also found an area with high structural boundary indices and low two-dimensionality near some reported active folds beneath the Shonai Plain. A dip-angle index for a reverse-fault-like density structure showed results inconsistent with the dip angles observed on outcrop. To circumvent this contradiction, we propose the hypothesis that the EBFZSP, currently acting as a reverse fault, has a normal-fault-like density structure and we then attempt a phenomenological interpretation. The dip-angle index may be helpful only in simple situations. [ABSTRACT FROM AUTHOR]

A series of protonated porphyrin J-aggregates of various water-insoluble tetraphenylporphyrin derivatives were prepared by aggregation at the liquid-liquid or gas-liquid interface. The absorption peak shifts suggest that the energy levels of the S1 exciton of the porphyrin J-aggregates depend on the substituents.