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• Switching impulse discharge experiments of rod-plane air gaps with different front times and absolute humidity are carried out. • Corrected U 50% of different front times when considering atmospheric parameters and absolute humidity. • Analyzed the main influencing factors of air gap discharge time under different conditions. In long-distance transmission lines, the switching overvoltage waveform differs from that of ordinary lines. The wave front time is primarily distributed above 1000 μs. And the switching overvoltage waveform has an important influence on the design of external insulation. This paper aims to deeply study the effect of various factors on the discharge of air gaps under the long front switching impulse voltage. This paper selects three kinds of rod-plane air gaps, and the switching impulse discharge experiments with different front lengths and absolute humidity under positive polarity are carried out. The effects of front time T f , absolute humidity h , and gap distance d on the discharge characteristics of the air gap are analyzed. The results show that the U 50% of an air gap is positively correlated with absolute humidity, front time, and gap distance. When considering the additional influence of humidity, the humidity additional influence factor c and the atmospheric parameter influence index n at different front times are almost unchanged. With the increase in gap distance, the influence of front time on U 50% is more obvious. With the growth of the operating wave front time, the rising rate of U 50% tends to slow down. The discharge time of the air gap under different conditions is mainly determined by the front time. The research results can provide a theoretical and experimental reference for the influence of front time T f and atmospheric parameters on the discharge characteristics of air gaps under long front switching impulse. [ABSTRACT FROM AUTHOR]

ABSTRACT Recently, Tzung-Her Chen, Wei-Bin Lee, and Hsing-Bai Chen (CLC) proposed a new three-party password-based authenticated key exchange (3PAKE) protocol. This CLC protocol needs not store the security-sensitive table on the server side, which reduces the danger of the server being compromised; also, it has the advantage in terms of the round efficiency and computational cost. However, we find that the leakage of values VA and VB in the CLC protocol will make a man-in-the-middle attack feasible in practice. On the basis of this finding, we present a modified 3PAKE protocol called I-CLC protocol, which is essentially an improved CLC protocol. I-CLC can resist attacks available, including the man-in-the-middle attack that we mentioned on the initial CLC protocol. Meanwhile, the new protocol allows that the participants choose their own passwords by themselves; additionally, the computation cost of I-CLC is lower than that of CLC protocol. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: To explore a new identification and protection method of the parathyroid gland in reoperation for thyroid diseases., Method: 54 patients receiving reoperation for thyroid diseases were selected. The experiment group intraoperatively adopted carbon nanoparticles suspension for negative development of the parathyroid gland, whereas the control group did not use carbon nanoparticles suspension., Results: At 48 h after surgery, the parathyroid hormone level was lower than the normal state in 9 patients (33.30%) of the control group and 1 patient (3.70%) of the experiment group; meanwhile, 6 months after surgery, 8 patients of the control group (29.63%) and 1 patient of the experiment group (3.70%) showed a lower level than the normal state with statistical differences. The serum calcium level in 10 patients of the control group (37.04%) and 2 patients of the experiment group (7.41%) was lower than the normal state at 48 h after surgery, while a lower level than the normal state was also shown in 8 patients of the control group (29.63%) and 1 patient of the experiment group (3.70%) 6 months after surgery with statistically significant between the two groups. A total of 10 (37.04%) and 1 parathyroid gland (3.70%) were detected with a statistical difference in both groups., Conclusion: By adopting carbon nanoparticles in reoperation for the thyroid diseases and negative development of the parathyroid gland for identification and protection of the parathyroid gland, the incidence of hypoparathyroidism is reduced effectively, thus improving the postoperative quality of life of the patients.

Background: The aim of this study was to explore a new method to identify and protect parathyroid glands in neck lymph node dissection for patients with thyroid cancer., Material and Methods: One hundred patients with thyroid cancer underwent total thyroidectomy combined with central neck lymph node dissection. During the operation, 50 patients receiving nano-carbon suspension were included in the experiment group, and 50 patients without nano-carbon suspension were included in the control group. We compared changes in parathyroid hormone levels before surgery and at 48 h after surgery between the 2 groups and of serum Ca^2+ level within 48 h after surgery, as well as postoperative parathyroid pathological and lymph node dissection results., Results: Eight and 1 parathyroid glands were detected pathologically in the control and experimental group, respectively. Decrease in parathyroid hormone level at 48 h occurred in 7 patients in the control group and 1 patient in the experimental group. Hypocalcemia was found at 48 h after surgery in 10 patients in the control group and 2 patients in the experimental group., Conclusions: Nano-carbon suspension can cause development of the thyroid gland and the central lymph node and a negative development of parathyroid glands. Careful identification and removal of black-stained lymphatic tissues in the process of total thyroidectomy with neck lymph node dissection can ensure a complete lymph node dissection and prevent parathyroid damage, thus effectively reducing the incidence of hypoparathyroidism.

Aim: To summary the experience for prevention and treatment of recurrent laryngeal nerve (RLN) injury in thyroid surgery., Methods: Clinical features of 623 patients who received thyroid surgery from January 2010 to December 2012 were analyzed retrospectively, and the features of RLN injury and intraoperative as well as postoperative treatments were reviewed., Results: RLN injury occurred in 31 patients (4.98%), in which, unilateral RLN injury occurred in 27 patients and bilateral RLN injuries occurred in 4 patients (temporary injury in 28 patients and permanent injury in 3 patients). 6 patients underwent RLN anastomosis during surgery and exhibited transient hoarseness after surgery. RLN exploration and decompression was given in 1 patient and the patient got normal vocal cord motion 2 months after surgery. 1 patient with bilateral injuries received tracheotomy and CO2 laser resection of arytenoid cartilage and achieved recovery 1 year later., Conclusions: In order to prevent RLN injury, the anatomic variations of RLN should be mastered. Routine exposure of RLN can effectively prevent the injury in patients receiving the second or multiple surgeries. Early interventions for RLN injury include mainly early discovery, early exploration and early anastomosis, and the function of RLN in some patients can recover completely. Subsequent treatments mainly focus on the improvement of the voice, expansion of glottis and melioration of dyspnea.

This study was carried out to evaluate the clinical presentation, surgical treatment, complications, and risk of malignancy for large substernal goiter. From March 2010 to December 2012, 12 patients with large substernal thyroid goiter who underwent surgery in our Department were enrolled in the study. Their medical records were retrospectively analyzed. Collar-shaped incision was adequate for resection of the lesions in 10 (83%) patients, while two (17%) patients required combined cervical-thoracic incision. In addition, one case was subjected to postoperative tracheotomy. Transient hypocalcaemia occurred in one case. The incidence of transient hoarseness, tracheomalacia and hypothyroidism was 8.3%. There was no perioperative bleeding, thyroid storm as well as other serious complications. All patients were clinically cured. Therefore, cervical collar incision is nearly always adequate for most cases of larger substernal goiter, and sternotomy can be avoided. Furthermore, the application of intraoperative ultrasonic knife can effectively reduce intraoperative and postoperative complications. Aggressive perioperative management is crucial for the successful removal of large substernal goiter.