Evaluation of the efficacy of unipolar and bipolar spinal dorsal root ganglion radiofrequency thermocoagulation in the treatment of postherpetic neuralgia

Jianjun Zhu,Ge Luo,Qiuli He,Ming Yao 대한통증학회 2022 The Korean Journal of Pain Vol.35 No.1

Background: Different views have been proposed on the radiofrequency treatment modes and parameters of radiofrequency thermocoagulation of the spinal dorsal root ganglion for the treatment of postherpetic neuralgia (PHN). It is urgent to identify a more effective therapy for patients with PHN. Methods: Patients who underwent radiofrequency thermocoagulation therapy for PHN were retrospectively reviewed and were divided into a radiofrequency thermocoagulation (CRF) and double neddles radiofrequency thermocoagulation (DCRF). The pain scores (numerical rating scale, NRS) were evaluated at the following time points: before the operation, 1 day, 3 months, 6 months, 1 year, and 2 years after operation. The incidence of complications and the degree of pain relief were evaluated. The in vitro ovalbumin experiment was used to indicate the effects of radiofrequency thermocoagulation. Results: Compared with the preoperative NRS scores, the postoperative NRS scores decreased significantly; the NRS scores of the DCRF group was lower than that of the CRF group at all time points from 6 months to 2 years following the operation. The total effective rate of the DCRF group was significantly higher than that of the CRF group at 2 years following the operation. The incidence of numbness in the DCRF group was higher than that noted in the CRF group. The ovalbumin experiments in vitro indicated that the effects of radiofrequency thermocoagulation were optimal when the distance between the two needles was 5 mm. Conclusions: DCRF with a 5 mm spacing exhibits a longer duration and higher effective rate in the treatment of PHN and is worth promoting.

A new method of synthesis on high-quality AgGaS2 polycrystalline

Jianjun Zhang,Shifu Zhu,Beijun Zhao,Baojun Chen,Zhiyu He 한국물리학회 2010 Current Applied Physics Vol.10 No.2

High-pure, single-phase, free of voids and high mass density AgGaS2 polycrystalline was synthesized by a new method, i.e. two-temperature zone vapor-transporting together with the mechanical and melt temperature oscillation method (TVMMTOM), directly from high-purity (6 N) elements silver, gallium and sulfur with excess sulfur. The mechanism and advantages of the new method for synthesizing high-quality AgGaS2 were discussed. It is found that the polycrystalline material synthesized by the new method is superior to that synthesized by the conventional method, what is more the new method can avoid the explosion of the synthetic quartz ampoule. Adopting the modified Bridgman method an integral and crack-free AgGaS2 single crystal with diameter of 14 mm and length of 63 mm has been obtained. It was found that there was a (1 0 1) cleavage face and the four order X-ray spectrum of the {1 0 1} faces was observed. By the method of DSC analysis the melting and freezing points of the AgGaS2 single crystal were about 995 and 955 ℃. The transmission spectra of the AgGaS2 sample of 10 × 8 ×2㎣ were obtained by means of UV and IR spectrophotometer. The limiting wavelength was 470 nm and the band gap was 2.64 eV. It can be found in the infrared spectrum that the infrared transmission was above 55%from 4000 to 800 cm-1, and the infrared transmittance of the crystal is up to 63% at 10.6 lm, which is higher than that of the crystal grown using polycrystalline materials synthesized by the conventional method. The value of a in 10.6 lm was 0.267 cm-1. Above mentioned results showed that the crystal was of good quality and TVMMTOM is preferable for synthesizing high-quality AgGaS2 polycrystalline materials.

Investigation of dynamic characteristics of planetary gear stage in wind turbine considering voltage dip

Jianjun Tan,Caichao Zhu,Chaosheng Song,Xiangyang Xu,Zi Wang 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.9

The transient variation of electrical parameters makes system loads fluctuate and reduces bearing capacity when the grid voltage dips. This work proposes an electromechanical coupling dynamic model of the wind turbine drivetrain to build a dynamic interconnection between the electric and drivetrain subsystems. The drivetrain subsystem that includes an improved model of the planetary gear stage is developed and validated. This improved model considers the carrier and planet bearing clearances, the connection relationship among the carrier, main shaft, and planets as well as the flexibilities of the main shaft and parallel stage shafts. The influences of the carrier bearing clearances, non-torque load and planet position angle on planet bearing loads are investigated under the low-voltage ride through (LVRT) event. The results indicate that as the LVRT occurs, the planet bearing loads reduce below the minimum requisite with a high, fluctuating system speed; considering the bearing clearances, the impacts occur in the planet bearing in the minimum load zone followed by significant stress variation; the non-torque load suppresses the planet bearing impacts in a limited range of carrier bearing clearance; the planet position angle has a significant effect on the planet bearing impacts because of the asymmetry of load and structure of the planetary gear stage.

Synthesis of rGO/TiO2/CdS Nanocomposites and its Enhanced Photoelectrochemical Performance in Determination of Parathion-Methyl

Jianjun Shi,Yan Wang,Li-Rong Meng,Jing-Chun Zhu,Ruiwen Shu,Jie He 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.5

A photoelectrochemical (PEC) sensor for the determination of organophosphate pesticides (OPs) was developed based on rGO/TiO2/CdS photoactive nanomaterials. The rGO/TiO2/CdS nanocomposites were prepared by solvothermal method and electrochemical deposition technique successively. The morphologies and structures of the as-prepared nanocomposites were extensively investigated by SEM and XRD. In alkaline condition, p-nitrophenol as the hydrolysate of parathion-methyl (PM) could be obtained by a simple hydrolyzation process. Under optimal conditions, the rGO/TiO2/CdS NPs modified ITO electrode exhibited a good PEC performance toward the hydrolysate of PM. The photocurrent intensity was enhanced with the increase of the concentration of the hydrolysate of PM. The proposed PEC method could detect PM in the range from 0.05 nmol L -1 to 10 nmol L -1 with a detection limit of 0.02 nmol L -1 (S/N = 3). Thus, the excellent performance of the rGO/TiO2/CdS nanocomposites serve as the matrix of the sensor, which provides a new way for the fabrication of high-sensitivity PEC sensing system.

The mixed substructure synthesis method with physics-impedance-modal parameter

Wang, Jianjun,Li, Qihan,Zhu, Zhigen Techno-Press 1999 Structural Engineering and Mechanics, An Int'l Jou Vol.8 No.5

Based on the concept of the parameter-mixed synthesis, this paper presents a mixed formulation of the substructure synthesis method in terms of the physics-impedance-modal parameter. An example is given to show the validity of this method.

Identification, sequence analysis, and infectivity of H9N2 avian influenza viruses isolated from geese

Rui Zhu,Xueqin Yang,Jianjun Zhang,Danwen Xu,Jiawen Fan,Huoying Shi,Shifeng Wang,Xiufan Liu 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.3

The subtype H9N2 avian influenza virus greatly threatens the Chinese poultry industry, even with annual vaccination. Waterfowl can be asymptomatically infected with the H9N2 virus. In this study, three H9N2 virus strains, designated A/Goose/Jiangsu/YZ527/2011 (H9N2, Gs/JS/YZ527/11), A/Goose/Jiangsu/SQ119/2012 (H9N2, Gs/JS/SQ119/12), and A/Goose/Jiangsu/JD564/2012 (H9N2, Gs/JS/JD564/12), were isolated from domestic geese. Molecular characterization of the three isolates showed that the Gs/JS/YZ527/11 virus is a double-reassortant virus, combining genes of A/Quail/Hong Kong/G1/97 (H9N2, G1/97)-like and A/Chicken/Shanghai/F/98 (H9N2, F/98)-like; the Gs/JS/SQ119/12 virus is a triple-reassortant virus combining genes of G1/97-like, F/98-like, and A/Duck/Shantou/163/2004 (H9N2, ST/163/04)-like. The sequences of Gs/JS/JD564/12 share high homology with those of the F/98 virus, except for the neuraminidase gene, whereas the internal genes of Gs/JS/YZ527/11 and Gs/JS/SQ119/12 are closely related to those of the H7N9 viruses. An infectivity analysis of the three isolates showed that Gs/JS/SQ119/12 and Gs/JS/YZ527/11 replicated well, with seroconversion, in geese and chickens, the Gs/JS/JD564/12 did not infect well in geese or chickens, and the F/98 virus only infected chickens, with seroconversion. Emergence of these new reassortant H9N2 avian influenza viruses indicates that these viruses can infect both chicken and goose and can produce different types of lesions in each species.

Identification of Landslide Region Based on Topographic and Change Information

Minsi Ao,Jianjun Zhu,Changcheng Wang,Xiaoying Yu 보안공학연구지원센터(IJSIP) 2014 International Journal of Signal Processing, Image Vol.7 No.1

Influence of pump start-up mode on the stability of mixed-flow pumps

Zhenbo Tang,Guojun Zhu,Jianjun Feng,Yajun Wu,Kai Liu,Qiang Lu 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.6

To analyse the influence of the start-up mode on the stability of the mixed-flow pump, start-up experiments are performed. And the external characteristic parameters, pressure fluctuation and shaft vibration data are collected by a multi-channel synchronous signal acquisition system during start-up. These data are analyzed by the time-frequency analysis method and wavelet partial coherence analysis method. Results reveal a positive correlation between the impeller angular acceleration and the time change rate of external characteristic parameters. During the start-up process, the variation law of the external characteristic parameters similar with the law of impeller rotating speed rise. The amplitude of the shaft vibration has a positive correlation with the start-up acceleration of the impeller. The influence of guide vane pressure fluctuations on the shaft vibrations is greater within 0~2 s after the start of the mixedflow pump. With the strart-up time extension, the partial coherence between the shaft vibration and the pressure fluctuations in guide vane is enhanced in low frequency band, which increases the risk of flow-induced vibration of the pump shaft.

Optimization Research of Effective Stimulation for Carbonate Reservoir and its Application

Anle He,Dawei Zhu,Chong Liang,Hewen Zhang,Jun Yan,Jianjun Xu 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.3

Based on the characteristics of carbonate reservoirs, staged-fracturing technology for horizontal wells was adopted to effectively drain the reservior. Fracture parameters including orientation, number, length, fracture conductivity and distribution were optimized, and accordingly a hydraulic fracturing design was developed. Applied in oilfield, this method was proved to be effective in oil production. Therefore, it can provide theoretical guidance for the design of the stage-fractured horizontal wells.

Evaluation and Comparison of Predictive Value of Tumor Regression Grades according to Mandard and Becker in Locally Advanced Gastric Adenocarcinoma

Yilin Tong,Yanmei Zhu,Yan Zhao,Zexing Shan,Dong Liu,Jianjun Zhang 대한암학회 2021 Cancer Research and Treatment Vol.53 No.1

Purpose Tumor regression grade (TRG) has been widely used in gastrointestinal carcinoma to assess pathological responses to neoadjuvant chemotherapy (NCT). There are various standards without a consensus, and it is still unclear which kind of system has better predictive value. This study aims to investigate and compare the predictive ability of the Mandard and Becker TRGs in patients with locally advanced gastric cancer. Materials and Methods A total of 290 patients with locally advanced gastric adenocarcinoma who underwent NCT and curative surgery were studied. Survival analysis for overall survival (OS) and disease-free survival (DFS) were based on the Kaplan-Meier method and Cox proportional hazards method. Predictive values of TRGs and models were assessed by time-dependent receiver operating characteristic (ROC) curve, the area under the ROC curve (AUC), nomogram, and calibration curve. Results In multivariable analysis, the Mandard TRG was associated with OS (hazard ratio [HR], 1.806; p=0.026) and DFS (HR, 1.792; p=0.017). The Becker TRG was also related to OS (HR, 1.880; p=0.014) and DFS (HR, 1.919; p=0.006). The Mandard and Becker TRG AUCs for 5-year survival were 0.72 and 0.71, respectively. The whole models showed an increased predictive value, with AUCs of 0.85 and 0.86, respectively. There was no significant difference between the two TRGs and two models. Conclusion TRG was an independent predictor for survival, and there was no significant difference between these two systems.