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This paper analyzed the strong motion characteristics based on 86 three-component strong motion records of the MW 6.6 Luding earthquake. Additionally, the factors that influence the variation in ground motion for three earthquakes with similar magnitude in Sichuan Province were investigated. The analysis result indicates a strong correlation between the observed ground motion parameters and the distribution of published Modified Mercalli Intensity. The residual analysis reveals that the spectral accelerations at periods 0.1–10.0 s are amplified to 0.0798–0.3057 times the mean level in the rupture forward direction and weakened to 0.0738–0.2831 times the mean level in the rupture backward direction. The maximum pulse direction recorded by the 51LDJ station is N6°E, aligning with the vertical fault direction. The velocity pulses has distinct bidirectional pulses in the waveforms, with a PGV of 37.0 cm/s. The source effect of the strike-slip MW 6.6 Luding and MW 6.5 Jiuzhaigou earthquakes on ground motion is relatively less significant compared to the average level of mainshocks in southwest China. However, the thrust-fault MW 6.7 Lushan earthquake exhibits a stronger source effect on ground motion during short and medium periods, but a weaker source effect during long periods when compared to the average level. The anelastic attenuation of the Longmenshan, Xianshuihe, and Huya fault zones in Sichuan exhibits significant regional variation and periodic correlation. This phenomenon is closely linked to the regional tectonic background variations and the heterogeneity of crustal structure within the area. [ABSTRACT FROM AUTHOR]

It is classical that certain truncations of the translation quiver Z Q appear in the Auslander-Reiten quiver. The stable n-translation quiver Z | n − 1 Q is introduced as a generalization of Z Q in studying higher representation theory. In this paper, we find conditions for a Hom-finite k-category to be realized as the bound path category of a convex full subquiver of a stable n-translation quiver. We show that the n-preinjective component and n-preprojective component of n-slice algebra are realized as the bound path categories of some truncations of Z | n − 1 Q o p . We also use Z | n − 1 Q o p to describe the νn-closure of Γ in the derived category. [ABSTRACT FROM AUTHOR]

In order to provide a palynological guide for the identification of insect‐carrying pollen grains, we studied the pollen grains of 10 anemophilous species and 10 entomophilous species in the Beijing urban area using light and scanning electron microscopies. We found that anemophilous pollen grains are small, spheroidal, or oblate spheroidal, while entomophilous pollen grains are medium and oblate. Comparison of the exine thickness and surface ornamentation showed that anemophilous pollen grains have significantly thinner exine and smoother surface ornamentation than entomophilous pollen grains. The results also revealed pollen characteristics adaptive to different pollination types. Overall, our study indicated that pollen morphology might be helpful for preliminary identification of anemophilous and entomophilous pollen. [ABSTRACT FROM AUTHOR]

Abstract: The electroreduction of oxygen was firstly studied on Ag/Co3O4–C in alkaline media prepared by depositing Ag on Co3O4 modified carbon (Co3O4–C). The Ag/Co3O4–C composite not only displayed relatively large electrochemical active surface area (ESA), high catalytic activity towards oxygen reduction reaction (ORR), but also exhibited good methanol tolerance and stability in alkaline media. Ag/Co3O4–C could be a valuable catalyst for ORR and be applied to alkaline fuel cells and metal–air batteries. [Copyright &y& Elsevier]

Objective: To evaluate the effect of perioperative dexamethasone on postoperative complications after pancreaticoduodenectomy., Background: The glucocorticoid dexamethasone has been shown to improve postoperative outcomes in surgical patients, but its effects on postoperative complications after pancreaticoduodenectomy are unclear., Methods: This multicenter, double-blind, randomized controlled trial was conducted in four Chinese high-volume pancreatic centers. Adults undergoing elective pancreaticoduodenectomy were randomized to receive either 0.2 mg/kg dexamethasone or a saline placebo as an intravenous bolus within 5 minutes after anesthesia induction. The primary outcome was the Comprehensive Complication Index (CCI) score within 30 days after the operation, analyzed using the modified intention-to-treat principle., Results: Among 428 patients for eligibility, 300 participants were randomized and 265 were included in the modified intention-to-treat analyses. One hundred thirty-four patients received dexamethasone and 131 patients received a placebo. The mean (SD) CCI score was 14.0 (17.5) in the dexamethasone group and 17.9 (20.3) in the placebo group (mean difference: -3.8; 95% CI: -8.4 to 0.7; P = 0.100). The incidence of major complications (Clavien-Dindo grade ≥III; 12.7% vs 16.0%, risk ratio: 0.79; 95% CI: 0.44 to 1.43; P = 0.439) and postoperative pancreatic fistula (25.4% vs 31.3%, risk ratio: 0.81; 95% CI: 0.55 to 1.19; P = 0.286) were not significantly different between the two groups. In the stratum of participants with a main pancreatic duct ≤3 mm (n = 202), the CCI score was significantly lower in the dexamethasone group (mean difference: -6.4; 95% CI: -11.2 to -1.6; P = 0.009)., Conclusions: Perioperative dexamethasone did not significantly reduce postoperative complications within 30 days after pancreaticoduodenectomy., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The challenges of clinical translation of optical imaging, including the limited availability of clinically used imaging probes and the restricted penetration depth of light propagation in tissues can be avoided using Cerenkov luminescence endoscopy (CLE). However, the clinical applications of CLE are limited due to the low signal level of Cerenkov luminescence and the large transmission loss caused by the endoscope, which results in a relatively low detection sensitivity of current CLE. The aim of this study was to enhance the detection sensitivity of the CLE system and thus improve the system for clinical application in the detection of gastrointestinal diseases., Methods: Four optical fiber endoscopes were customized with different system parameters, including monofilament (MF) diameter of imaging fiber bundles, fiber material, probe coating, etc. The endoscopes were connected to the detector via a specifically designed straight connection device to form the CLE system. The β-2-[ 18 F]-Fluoro-2-deoxy-D-glucose ( 18 F-FDG) solution and the radionuclide of Gallium-68 ( 68 Ga) were used to evaluate the performance of the CLE system. The images of the 18 F-FDG solution acquired by the CLE were used to optimize imaging parameters of the system. By using the endoscope with optimized parameters, including the MF diameter of imaging fiber bundles, fiber materials, etc., the resolution and sensitivity of the assembled CLE system were measured by imaging the radionuclide of 68 Ga., Results: The results of 18 F-FDG experiments showed that larger MF diameter led to higher collection efficiency. The fiber material and probe coating with high transmission ratios in the range of 400-900 nm also increased signal collection and transmission efficiency. The results of 68 Ga evaluations showed that a minimum radioactive activity of radionuclides as low as 0.03 µCi was detected in vitro within 5 minutes, while that of 0.68 µCi can be detected within 1 minute. In vivo experiments also demonstrated that the developed CLE system achieved a high sensitivity at a submicrocurie level; that is, 0.44 µCi within 5 minutes, and 0.83 µCi within 1 minute. The weaker in vivo sensitivity was due to the attenuation of the signal by the mouse tissue skin and the autofluorescence interference produced by biological tissues., Conclusions: By optimizing the structural parameters of fiber endoscope and imaging parameters for data acquisition, we developed a CLE system with a sensitivity at submicrocurie level. These results support the possibility that this technology can clinically detect early tumors within 1 minute., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://dx.doi.org/10.21037/qims-21-373). The authors have no conflicts of interest to declare., (2022 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

Objective: Transarterial treatment of direct carotid cavernous fistulas (DCCF) via embolic materials has been well documented. This study reports, validates, and compares with existing literature our experience treating DCCFs via endovascular approaches by using detachable balloons, coils, and covered stents., Methods: Between June 2006 to October 2011, 32 patients (21 male, 11 female) with 32 DCCFs (30 traumatic, 2 spontaneous cavernous ICA aneurysms) were embolized endovascularly. Followup was performed for at least 6 months., Results: Among the 32 DCCFs, 21 (65.6%) were embolized using detachable balloons, eight (25.0%) with coils, one (3.1%) with balloons and coils, and two (6.3%) with covered stents. Complete DCCF obliteration was achieved in 31 (96.9%) cases. One fistula failed to respond due to premature balloon detachment. Intracranial bruit in 31 (100%) chemosis and exophthalmos in 28 (100%) cases resolved after embolization. Visual acuity and oculomotor palsy improved in 18 (90%) and 18 (69.2%) cases, respectively. There was no evidence of DCCF recurrence. Thirteen DCCFs were followed up by MRI and five by DSA. In these cases, four (4/13, 30.8%) balloon-embolized DCCFs showed pseudoaneurysms. Three patients were asymptomatic; one had minor left oculomotor palsy., Conclusions: Our results correlate and reinforce literature regarding endovascular treatment of DCCFs. Application of Transarterial embolization with detachable balloons, despite extensive use has been decreasing. Coil embolization is an effective and safe alternative for treatment, especially when balloon embolization fails. Covered stent placement may be used as another alternative for selected cases.