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Low-frequency transmission system (LFTS) based on modular multilevel matrix converter (M3C) has great application potential in offshore wind power transmission,urban power grid and long-distance power transmission. In order to study the startup process and the control strategies of LFTS and connect the converter station to the low-frequency transmission line without voltage or current impulse of M3C,a startup method of undisturbed grid connection is proposed. Firstly,the structure and operating principle of the LFTS are analyzed. Then,the selection principle of sub modules and the charging process of M3C are analyzed with two-terminal LFTS as the target. Taking the advantage that the blocked M3C does not exchange power with the low-frequency power grid when the capacitor is at rated voltage,the problems of over-voltage and over-current that tend to occur during LFTS startup can be solved by flexible control of M3C and reasonable design of startup strategy,without additional control devices and detecting the synchronization of the breaker. Finally,a real time digital simulation system (RTDS) is built to verify the proposed startup method. The simulation results show that converter stations connect to the low-frequency transmission line without voltage or current impulse. Also,the proposed strategy is correct and has a great prospect of the engineering application.

Glioblastoma multiforme (GBM) is the most common intracranial malignant tumor and is notorious for its poor prognosis. An important element in the short overall survival of GBM patients is the lack of understanding the pathogenesis and progression of tumor and deficiency biomarkers that can be used for early diagnosis and therapeutic sensitivity monitoring. Studies have shown that transmembrane protein 2 (TMEM2) is participated in tumorigenesis of various human tumors, including rectal and breast cancers. Although Qiuyi Jiang et al. have reported that TMEM2 combined with IDH1/2 and 1p19q can predict the survival time of glioma patients based on bioinformatics, its expression and biological role of glioma remain unclear. In our study, we investigated the effect of TMEM2 expression level on glioma malignancy in public datasets and an independent internal dataset. We revealed TEMM2 expression was higher in GBM tissues than in non-tumor brain tissues (NBT). Moreover, the increase in TMEM2 expression level was closely related to tumor malignancy. The survival analysis showed that TMEM2 high expression reduces survival time in all glioma patients, including GBM and LGG patients. Subsequent experiments demonstrated that knockdown TMEM2 inhibited proliferation of GBM cells. In addition, we analyzed TMEM2 mRNA levels in different GBM subtypes, and demonstrated that TMEM2 expression was upregulated in mesenchymal subtype. Meanwhile, bioinformatics analysis and transwell assay indicated that knockdown TMEM2 suppressed epithelial-mesenchymal transition (EMT) in GBM. Importantly, Kaplan–Meier analysis demonstrated that TMEM2 high expression reduced the treatment response to TMZ in GBM patients. Knockdown of TMEM2 alone did not reduce apoptosis GBM cells, but significant apoptotic cells were observed in the group treated with additional TMZ. These studies may contribute to improving the accuracy of early diagnosis and evaluating the effectiveness of TMZ treatment in GBM patients.

Introduction: Pure ventricular hemorrhage is often secondary to Moyamoya disease, rarely caused by rupture of ventricular aneurysm. The surgical treatment of the latter is very challenging. 3D Slicer reconstruction technology can accurately locate small intracranial lesions and combined with minimally invasive surgery with transcranial neuroendoscope is a new attempt to treat the above diseases. Case presentation: We report a case of pure intraventricular hemorrhage secondary to rupture of a distal segment aneurysm of the anterior choroidal artery. Brain computed tomography (CT) before admission showed pure ventricular hemorrhage, and brain CT angiography (CTA) before operation showed a distal segment aneurysm of the anterior choroidal artery. We used 3D Slicer reconstruction and precise location of the focus before the operation and used the minimally invasive surgery technique with transcranial neuroendoscope to completely remove the hematoma in the ventricle, and found the responsible aneurysm located in the ventricle. Conclusion: Pure intraventricular hemorrhage requires vigilance against the distal segment aneurysm of the anterior choroidal artery. At present, conventional microscopic craniotomy and intravascular interventional therapy have limitations, and 3D Slicer reconstruction and precise positioning technology combined with transcranial neuroendoscope minimally invasive surgery may be a good choice.

Objective: This retrospective study was performed to evaluate the feasibility and safety of surgically clipping intracranial aneurysms using a transcranial neuroendoscopic approach. Methods: A total of 229 patients with cerebral aneurysms were included in our study, all of whom were treated with clamping surgery at Wuhan University People’s Hospital. They were divided into neuroendoscopic and microscopic groups, according to whether or not neuroendoscopy was used for the clamping surgery. We statistically analyzed the patients’ baseline data, surgical outcomes, and complications, which were then evaluated to assess the treatment effect. Results: The baseline characteristics were not statistically significant, except for gender, for which the proportions of female patients in the two groups were 69 (56.1%) and 46 (43.4%). There were no patients with incomplete aneurysm clamping or parent vessel occlusion in the neuroendoscopic group, and there were 4 (3.8%) and 2 (1.9%) in the microscopic group, respectively; however, there was no statistically significant difference in the comparison of the two groups. The mean operative times of the two groups were 181 min and 154 min, respectively, and were statistically different. However, the mRS scores of the two groups showed no significant difference in patient prognosis. The differences in complications (including limb hemiplegia, hydrocephalus, vision loss, and intracranial infection) were not statistically significant, except for cerebral ischemia, for which the proportions of patients in the two groups were 8 (6.5%) and 16 (15.1%). Conclusions: Neuroendoscopy can provide clear visualization and multi-angle views during aneurysm clipping, which is helpful for ensuring adequate clipping and preventing complications.

This paper summarized the nursing experience of a patient with pain caused by periarthritis of the shoulder treated with the combined application of Traditional Chinese Medicine (TCM) characteristic nursing techniques. Followed by the auricular acupoint massage, the auricular acupoint blood-letting therapy was performed to relieve the shoulder pain and discomfort. The auricular acupoint sticking and pressing therapy showed a long-term stimulation effect, while the balanced cupping therapy was able to enhance the local stimulation effect. The combined application of TCM characteristic nursing techniques are effective in relief of pain in patients with acute periarthritis of the shoulder, which is worthy of promoting. (本文总结了中医特色护理技术联合应用治疗1例肩周炎疼痛患者的护理体会。在耳部按摩的基础上进行耳穴放血, 以减轻肩关节疼痛和缓解肩关节不适, 耳穴贴压则可以起到持续刺激的作用, 平衡火罐作用于局部, 以达到加强刺激的效果。联合疗法能够更好地缓解肩周炎发作期患者的疼痛症状, 值得临床借鉴。)