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Gate electrode inductance is a key factor for the controllable current capacity of unity-gain turn-off devices. However, the precise and credible measurement of this nH-level inductance is very difficult due to the compact structure of housing package. In this article, a precise measurement methodology of nH-level gate electrode inductance based on calculation-error-free algorithm for unity-gain turn-off devices is proposed. First, the turn-off process was modeled and discussed. Based on the feature of different stages, a customized extraction method is proposed for nH-level inductance measurement with ultrahigh accuracy. Then, a gate current measurement method for separate cathode rings with minimum inductance introduction was invented and discussed. After careful measurement and calculation, the gate electrode inductance for each region was derived and the abrupt change in gate contact region was observed and analyzed. The inductances measured in this article can be further utilized for housing structure optimization and lateral arrangement of segments on unity-gain turn-off chips. [ABSTRACT FROM AUTHOR]

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To investigate the protective effect of Ebselen on mitochondrial damage and its influence to Cytochrome C expression and the neuronal apoptosis after spinal cord injury in rats. Methods Sixty adult SD rats were randomly divided into 5 groups (12 each group). Spinal cord injury model was made using Allen's method. Sham operation group received only laminectomy; SCI group received laminectomy and spinal trauma; Saline group received saline injection intraperitoneally (0.1% DMSO) after injury; methylprednisolone group received 30 mg/kg methylprednisolone injection intraperitoneally, ebselen group received 10 mg/kg ebselen injection intraperitoneally. The malonaldehyde (MDA) and glutathione (GSH) level at the injured sites of the spinal cord were detected 24 hours after trauma, and the expression level of Cytochrome C was also observed. Finally, neuronal apoptosis was identified by TUNEL staining. Results MDA level in the Ebselen group was significantly lower than that in the SCI group, and GSH level was significantly elevated in the Ebselen group compared with SCI group (P<0.01). Expression of Cytochrome C in Ebselen group was lower than that in SCI group shown by Western blot, and the neuronal apoptosis in Ebselen group reduced significantly too compared with SCI group (P < 0.01). Conclusion Ebselen can alleviate peroxidation, prohibit expression of Cytochrome C and inhibit neuronal apoptosis, thus it shows a protective effect to experimental acute SCI. [ABSTRACT FROM AUTHOR]

Objective To detect the effects of the selective mitochondrial fission inhibitor-Mdivi-1 on the malondi-alolehyde (MDA), glutathione (GSH) as well as cytochrome C (Cyt-C) in neuronal mitochondria and neuronal apoptosis. Methods Thirty-six adult female SD rats (250-300 g) were randomly divided into 3 groups (n=12): sham operation (Sham) group, single spinal cord injury (SCI) group and Mdivi-1 pretreatment (1.20 mg/kg, Mdivi-1) group. In sham group, the rats spinal cord was exposed, but no hit. The rat model of spinal cord injury was established by Allen s method in SCI group and Mdivi-1 group. In Mdivi-1 group, rats were given Mdivi-1 through the tail vein 15 min before spinal cord injury, and SCI group received the same amount of dimethyl sulfoxide (DMSO). Rats in Sham group were sacrificed 8 h after exposing spinal cord. Rats in SCI group and Mdivi-1 group were sacrificed at 8 h after the spinal cord injury, then were removed the spinal cord T9-11. The contents of MDA and GSH in mitochondria of spinal cord tissues were detected with spectrophotometer. The expressions of Cyt-C protein in the mitochondria and cytoplasm were detected by Western blot assay. The neuronal apoptosis was assessed by TUNEL staining. Results Compared with Sham group, levels of Cyt-C and GSH in mitochondria were decreased significantly (P < 0.01), while levels of MDA in mitochondria, Cyt-C in cytoplasm and the neuronal apoptosis were increased significantly in SCI group (P < 0.01). Compared with SCI group, Cyt-C and GSH levels in mitochondria were increased significantly in Mdivi-1 group (P < 0.01), however, MDA in mitochondria, Cyt-C in cytoplasm and the neuronal apoptosis were significantly reduced (P < 0.01). Conclusion Mdivi-1 can relieve neurons from mitochondrial oxidative damage, inhibit the release of cytochrome C and neuronal apoptosis after acute spinal cord injury, which plays a role in promoting the recovery of spinal cord function. [ABSTRACT FROM AUTHOR]

Background: The Judet-Letournel classification has been widely used to diagnose acetabular fractures since it was proposed. However, there has been growing evidence of incompleteness and comprehension difficulty in this classification, which may adversely affect its clinical use. The purposes of this study were to introduce a novel 3-column classification system for acetabular fractures and to evaluate its reliability and reproducibility., Methods: A total of 1,028 patients with acetabular fractures, who had undergone surgical treatment from June 2011 to January 2017 in 7 level-I trauma centers, were recruited into this study. Preoperative radiographs and computed tomographic (CT) scans were conducted for each patient. To evaluate the reproducibility of the 3-column classification system for acetabular fractures, the interobserver and intraobserver reliability (kappa coefficient, κ) of this classification system compared with those of the Judet-Letournel classification system was investigated by 4 observers., Results: A total of 209 patients (20.33%) could not be classified by the Judet-Letournel classification, and 3 cases (0.29%) could not be classified by the novel 3-column classification. The mean κ value of the interobserver reliability for the Judet-Letournel classification was 0.591 (range, 0.508 to 0.681), indicating moderate agreement, whereas the mean κ value was 0.735 (range, 0.594 to 0.930), indicating substantial agreement, when using the 3-column classification. The mean κ value for the intraobserver reliability was 0.751 (range, 0.708 to 0.793) for the Judet-Letournel classification and 0.909 (range, 0.792 to 0.957) for the 3-column classification., Conclusions: The 3-column classification, based on the anatomic character of the acetabulum, showed higher interobserver and intraobserver reliability than the Judet-Letournel classification. Additionally, certain fracture patterns in the 3-column classification scheme generally correlated with surgical approaches. This novel classification system may be used as a supplement to the traditional Judet-Letournel classification system., Clinical Relevance: The 3-column concept of the acetabulum proposed in this study is helpful to master acetabular fractures for less experienced surgeons. The novel classification system could assist with acetabular fracture diagnosis and the choice of surgical approaches.