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Objectives: The type of ligamentous tear and the degree of knee laxity have important guiding significance for the diagnosis and management of anterior cruciate ligament (ACL) tears. Instrumental measurement is necessary for ACL tears since physical examination and magnetic resonance imaging (MRI) cannot provide an objective and quantitative assessment of knee laxity. This study aimed to compare the application of a novel knee arthrometer and simultaneous stress radiography in differentiating between complete and partial acute ACL tears, and further assess the correlation between the two measurements. Methods: A total of 106 patients with complete acute ACL tears and 52 patients with partial acute ACL tears were included in the study. Preoperative arthrometry and simultaneous stress radiography were performed using the Ligs arthrometer at 90, 120, and 150 N to assess side‐to‐side difference (SSD) in anterior knee laxity. The optimal threshold was determined using the receiver operating characteristic (ROC) curve. The area under the ROC curve (AUC) was used to assess the diagnostic value of the measurement. Pearson's correlation coefficient was used to assess the correlation between the two measurements. Results: The optimal differential SSD thresholds in the Ligs arthrometer were 2.7 mm at 90 N, 3.8 mm at 120 N, and 4.6 mm at 150 N. Similarly, the optimal differential SSD thresholds in simultaneous stress radiography were 3.8 mm at 90 N, 5.1 mm at 120 N, and 5.6 mm at 150 N. The AUC analysis revealed that the Ligs arthrometer was fairly informative at 90 N (AUC = 0.851), 120 N (AUC = 0.878), and 150 N (AUC = 0.884), and simultaneous stress radiography was highly informative at 90 N (AUC = 0.910), 120 N (AUC = 0.925), and 150 N (AUC = 0.948). Moreover, the AUC of the combined measurements was 0.914 at 90 N, 0.931 at 120 N, and 0.951 at 150 N. A significantly strong correlation was found between the two measurements at 90 N (r = 0.743, p < 0.001), 120 N (r = 0.802, p < 0.001), and 150 N (r = 0.823, p < 0.001). Conclusions: The Ligs arthrometer and simultaneous stress radiography proved to be valid diagnostic tools to differentiate between complete and partial acute ACL tears, with a strong correlation between the two measurements in SSD values. Compared with single instrumental measurement, the combination of the two measurements can further improve the diagnostic value in this regard. [ABSTRACT FROM AUTHOR]

Aiming at the significant needs of flexible DC converter valve applications in high-altitude areas, we investigate the effect of atmospheric neutrons on the failure rate of key core power devices in three kinds of converter valves, namely IGBTs, thyristors, and diodes. The safe working voltage boundary of the devices is obtained, and the failure rate caused by atmospheric neutrons in the real working environment of the power devices is calculated according to the results of the ground-accelerated irradiation test of atmospheric neutrons and the atmospheric neutron environment under the actual working conditions. The test results show that the failure rate of IGBTs, thyristors, and diodes caused by atmospheric neutrons is greatly affected by the blocking voltage, and the larger the blocking voltage is, the higher the failure rate of the device is. The research results can provide a basis for the design of the operating voltage of key core power devices of flexible DC converter valves and guide the evaluation of the failure rate and engineering design of the electronic system of DC ultra-high-voltage power transmission and transformation converter stations in the high-altitude environment of the Qinghai-Tibet Plateau. [ABSTRACT FROM AUTHOR]

This paper investigates the temperature-dependent effects of gamma-ray irradiation on β-Ga2O3 vertical Schottky barrier diodes (SBDs) under a 100 V reverse bias condition at a total dose of 1 Mrad(Si). As the irradiation dose increased, the radiation damage became more severe. The total ionizing dose (TID) degradation behavior and mechanisms were evaluated through DC, capacitance–voltage (C-V), and low-frequency noise (LFN) measurements by varying irradiation, and the test results indicated that TID effects introduced interface defects and altered the carrier concentration within the material. The impact of TID effects was more pronounced at lower temperatures compared to higher temperatures. Additionally, the annealing effect in the high-temperature experimental conditions ameliorated the growth of interface trap defects caused by irradiation. These results suggest that compared to low-temperature testing, the device exhibits higher TID tolerance after high-temperature exposure, providing valuable insights for in-depth radiation reliability studies on subsequent related devices. [ABSTRACT FROM AUTHOR]