Learning Curve and Complications of Unilateral Biportal Endoscopy: Cumulative Sum and Risk-Adjusted Cumulative Sum Analysis

Jinchao Xu,Dong Wang,Jidan Liu,Chengyue Zhu,Jianhang Bao,Wenshuo Gao,Wei Zhang,Hao Pan 대한척추신경외과학회 2022 Neurospine Vol.19 No.3

Objective: The purpose of this study was to investigate the learning curve and complications of unilateral biportal endoscopy (UBE) in the treatment of lumbar disc herniation (LDH) and lumbar spinal stenosis (LSS). Methods: This was a retrospective cohort analysis of 197 consecutive patients who received UBE unilateral laminotomy bilateral decompression (UBE-ULBD) or lumbar discectomy (UBE-LD) surgery, including 107 males and 90 females with an average age of 64.83 ± 14.29 years. Cumulative sum (CUSUM) and risk-adjusted cumulative sum analysis (RA-CUSUM) were used to evaluate the learning curve, with the occurrence of complications defined as surgical failure, and variables of different phase of the learning curve were compared. Results: The cutoff point of learning curve of UBE surgery was 54 cases according to CUSUM analysis. The learning curve of UBE-ULBD and UBE-LD were divided into 3 phases. The first cutoff points were 31 and 12 cases, and the second cutoff point were 67 and 32 cases respectively. With the progress of the learning curve, the operation time and postoperative hospital stays decreased. The visual analogue scale and Oswestry Disability Index at the last follow-up were significantly lower than that before surgery. The incidence of surgical failure was 6.11% and began to decrease after the 89th case based on RA-CUSUM analysis. The surgical failure rate decreased from 10.11% to 2.78 after the 89th case with significant different. Conclusion: UBE surgery is effective in the treatment of LDH and LSS with low incidence of complications. But a learning curve of at least 54 cases still required for mastering UBE surgery.

Fatigue Evaluation of Grouted Connections under Bending Moment in Offshore Wind Turbines Based on ABAQUS Scripting Interface

Xian Wang,Tao Chen,Qi Zhao,Guokai Yuan,Jinchao Liu 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.4

The fatigue behavior evaluation under bending moment is extremely important to the grouted connection in monopile offshore wind turbines. Based on the scripting interface of ABAQUS software, finite element model of the grouted connections was established automatically in accordance with the user defined parameters by Python language. Based on the experimental material test of grout material, the grout material was simulated by using three-dimensional concrete damaged plasticity (CDP) model in ABAQUS. Full model and half model were compared under fatigue limit state (FLS), and numerical results are presented in terms of hot spot stress in steel and third principle stress in grout material. It was found that half model could decrease calculation time significantly with more conservative evaluation result. Furthermore, parametric studies were conducted based on the half models about two different shear keys’ arrangements as well as the height and distance of shear keys. And it is found that there are slight differences for two models in calculated design life when the interface behavior between steel and grout material is modeled by Coulomb friction law.

Study on mass flow characteristics of fluidized bed with a circulative accelerating tube

Xiao Wang,Hui Si,Qi Cheng,Jinchao Kong,Dong Zhao 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.25 No.-

The heat transfer between annular fluidized-bed and the furnace can be enhanced by adding circulative accelerating tubes in the reactor. Cold state experiments were conducted to test the effect of operation conditions on particles flow in fluidized bed with a circulative accelerating tube. Results showed that the spouting velocity, fluidizing velocity and static bed height all had a beneficial effect on particles circulating efficiency. Shorter and moderate outlet needle nozzles were suitable for circulative accelerating tube to maximize circulating rate. What’s more, smaller size particles which had better fluidity should be chosen for the bed material to improve circulating efficiency.

The Silurian−Devonian granitoids in the East Kunlun orogenic belt, northern Qinghai-Tibetan plateau, China: origin and tectonic implications

Namkha Norbu,Yuegao Liu,Jinchao Li,Qunzi Jia,Wei Wang,Xiaobing Song,Yazhi Li,Huilei Kong,Yijie Gao,Xianzheng Guo,Xuegang Yao 한국지질과학협의회 2021 Geosciences Journal Vol.25 No.6

The East Kunlun orogenic belt (EKOB) is located in the northeastern part of the Qinghai-Tibetan Plateau, China. Voluminous Silurian–Devonian granitoids were formed during the Proto-Tethys Ocean subduction and collision process. In this study, zircon U-Pb age dating, in-situ Hf isotope analyses, and whole rock major and trace element analyses have been carried out on granitoids from the central to eastern EKOB. The formation ages of granodiorite in the Bairiqili area, the granodiorite in the Wulonggou area are 410 ± 2 Ma and 396 ± 1 Ma, respectively, and the granodiorites show I-type features. The Wulonggou syenogranite with a formation age of 398 ± 2 Ma has a high differentiation index (D.I. = 89.59–92.43), and may belong to the high fractionated I-type granite. The Lalangmai tonalite with a formation age of 423 ± 2 Ma has high Sr (339–590 μg/g), εHf(t) (1.5–7.3), and low Y (3.45–6.33 μg/g), which are similar to modern adakites. The Lalangmai tonalite is the latest adakite record during the Proto-Tethys evolution in EKOB. Combined with previous studies, it is concluded that the granitoids from Cambrian to Devonian divided into four episodes. The first episode (515–436 Ma) mainly consists of I-type island arc granites and adakite, which are formed in a subduction environment. The second episode (436–427 Ma) is characterized by the S-type granites related to the collision. The third episode (427–420 Ma) is the transition period between the collision and the post-collision environment. In the fourth episodes (420–385 Ma), granitoids were formed in post-collision extensional environment, which is characterized by I-type and A-type granites. The upwelling of asthenosphere material is likely caused by the collapse of the orogenic belt. After 420 Ma, I-type and A-type granites formed at different depths but in the same environment.

Deep electrical structure and dynamic mechanism of the Yinchuan Graben on the western margin of the Ordos Block

Gang Min,Bingxi Yin,Jinchao Chen,Yong Yang,Huiling Yuan,Yan Wang 한국지질과학협의회 2022 Geosciences Journal Vol.26 No.1

The Yinchuan Graben (YG) is situated in the transitional area between the Tibetan Plateau, Ordos Block (OB) and Alxa Block (AB). The dynamic mechanism of the YG is controversial because of its unique tectonic environment. This study used a broadband magnetotelluric profile constrained by high-density point spacing to reliably obtain the deep electrical structure across the Helanshan Orogenic Belt and YG and to discuss the dynamic mechanism of the YG. The main research results are as follows. 1) Our profile and previous seismic profiles show a low-resistivity and low-velocity body in the deep YG, which extends upward and cuts through the bottom boundary of the upper crust, and all results indicate that this body may be the result of partial melting due to upwelling mantle material. 2) Our profile also shows a high-resistivity anomaly in the middle–lower crust of the Helanshan orogenic belt, which can be interpreted as intrusive rocks formed by the emplacement of partially melted materials. 3) The Helanshan east piedmont fault dips eastward and intersects with the Yellow River fault at the depth of 20 km, and the typical structure of the intersection may be the seismogenic structure of the Pingluo Ms8.0 earthquake. 4) The evolution of the YG may have been controlled by various dynamic mechanisms, and the initial formation of the YG may have resulted from the upwelling mantle material beneath the northern OB; the evolution of the YG since 10 Ma may also have been affected by lateral mantle flow from the Tibetan Plateau to the gap between the OB and AB.

Synthesis and thermodynamic properties of a novel pyridinium-based asymmetrical gemini ionic liquid

Xuzhao Yang,Jun Wang,Wenyuan Zou,Jinchao Wu 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.12

A novel asymmetrical gemini ionic liquid (GIL), [1-(1-pyridinium-yl-hexyl)-6-methylpiperidinium] dihexafluorophosphate ([PyC6MPi][PF6]2) combined with pyridine, 1-methylpiperidine by 1,6-dibromohexane with PF6 − as anion, was synthesized and characterized by 1H NMR and IR. The molar heat capacity of the GIL was measured via differential scanning calorimetry from 298.15 K to 448.15 K under atmospheric pressure. No phase transition or other thermal anomaly was observed in the solid-phase region (298.15 K to 358.15 K) and liquid-phase region (403.15 K to 448.15 K). The basic properties and thermodynamic functions of the GIL, such as melting point, molar enthalpy and entropy of fusion, heat capacity, enthalpy HT-H298.15 K, and entropy ST-S298.15 K, were also determined from the experimental data. Thermal decomposition kinetics of [PyC6MPi][PF6]2 were investigated by using non-isothermal thermogravimetric analysis in pure nitrogen atmosphere at various heating rates. Thermal decomposition data were, respectively, correlated with Friedman method, Ozawa-Flynn-Wall equation, and ASTM model. The activation energy (E) and pre-exponential factor (logA) values were obtained by using the above three methods.

Improvement of the Multiple Image Encryption Capacity Using QR Code as a Data Container

Xing Bai,Jianping Hu,Sheng Yuan,Jinchao Wang,Jing Wang,Xin Zhou 한국광학회 2020 Current Optics and Photonics Vol.4 No.4

An image encryption scheme based on the quick response (QR) code as a data container has aroused wide interest due to the lossless recovery of the decrypted image. In this paper, we apply this method to multi-image encryption. However, since the decrypted image is affected by crosstalk noise, the number of multi-image encryptions is severely limited. To solve this problem, we analyzed the performance of QR code as a data container, and processed the decrypted QR code using the proposed method, so that the number of multi-image encryptions is effectively increased. Finally, we implemented a large image (256 × 256) encryption and decryption.

Molecular Cloning and Expression of a Cu/Zn-Containing Superoxide Dismutase from Thellungiella halophila

Xu Xiaojing,Zhou Yijun,Wei Shanjun,Ren Dongtao,Yang Min,Bu Huahu,Kang Mingming,Wang Junli,Feng Jinchao 한국분자세포생물학회 2009 Molecules and cells Vol.27 No.4

Superoxide dismutases (SODs) constitute the first line of cellular defense against oxidative stress in plants. SODs generally occur in three different forms with Cu/Zn, Fe, or Mn as prosthetic metals. We cloned the full-length cDNA of the Thellungiella halophila Cu/Zn-SOD gene ThCSD using degenerate RT-PCR and rapid amplification of cDNA ends (RACE). Sequence analysis indicated that the ThCSD gene (GenBank accession number EF405867) had an open reading frame of 456 bp. The deduced 152-amino acid polypeptide had a predicted molecular weight of 15.1 kDa, an estimated pI of 5.4, and a putative Cu/Zn-binding site. Recombinant ThCSD protein was expressed in Escherichia coli and assayed for SOD enzymatic activity in a native polyacrylamide gel. The SOD activity of ThCSD was inactivated by potassium cyanide and hydrogen peroxide but not by sodium azide, confirming that ThCSD is a Cu/Zn-SOD. Northern blotting demonstrated that ThCSD is expressed in roots, stems, and leaves. ThCSD mRNA levels increased by about 30-fold when plants were treated with sodium chloride (NaCl), abscisic acid (ABA), and indole-acetic acid (IAA) and by about 50-fold when treated with UVB light. These results indicate that ThCSD is involved in physiological pathways activated by a variety of environmental conditions.