The Investigation on Thermal Aging Characteristics of Oil-Paper Insulation in Bushing

Rui-jin Liao,En-de Hu,Li-jun Yang,Zuo-ming Xu 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.3

Bushing is the key link to connect outer and inner insulating systems and also the essential electric accessory in electric power system, especially in the high voltage engineering (AC 1000kV, DC 800kV). This paper presented the experimental research of thermal aging characteristic of oilpaper insulation used in bushing. A thermally accelerated aging experiment at 90℃ was performed. The bushing models containing five layers of paper were sealed into the aging vessels and further aged for 250 days. Then several important parameters associated with the aging were observed and evaluated. The results showed that the degree of polymerization (DP) of papers gradually decreased. The DP values of outermost layer and middle layer fit well into the second-order kinematic model and first-order kinematic model, respectively. Less deterioration speed of the inter-layer paper than outer layer was confirmed by the variation of DP. Hydrolysis was considered as the main cause to this phenomenon. In addition, the logarithm of the furfural concentrations in insulation oil was found to have good linear relationship with DP of papers. Interestingly, when the aging time is about 250 days and DP is 419, the aging process reaches an inflection point at which the DP approaches the leveling off degree of polymerization (LODP) value. Both tanδ and acid number of oils increased, while surface and volume resistivity of papers decreased. The obtained results demonstrated that thermal aging and moisture absorbed in papers brought great influence to the degradation of insulating paper, leading to rapid decrease of DP and increase of the tanδ . Thus, the bushing should be avoided from damp and real-time monitoring to the variation of tanδ and DP values of paper is an effective way to evaluate the insulation status of bushing.

Multiple Particle Production in Proton-proton Collisions at Energies Available at the Large Hadron Collider

Jin-Ming Feng,Cai-Xing Tian,Rui-Fang Si,Fu-Hu Liu 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.61 No.4

A shift three-source model is used in this paper to describe the multiplicity and the pseudorapidity distributions of final-state charged particles produced in proton-proton collisions at energies available at the Large Hadron Collider (LHC). The three kinds of sources are central sources arising from gluon-gluon collisions, target fragmentation sources arising from gluon- or quark-induced collisions with target quarks, and projectile fragmentation sources arising from gluon- or quark-induced collisions with projectile quarks. The central, target fragmentation, and projectile fragmentation sources each have shifts around their centers. The results calculated by using the shift three-source model are in agreement with the experimental data of the ALICE (A Large Ion Collider Experiment) and the CMS (Compact Muon Solenoid experiment) Collaborations.

The Investigation on Thermal Aging Characteristics of Oil-Paper Insulation in Bushing

Liao, Rui-jin,Hu, En-de,Yang, Li-jun,Xu, Zuo-ming The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.3

Bushing is the key link to connect outer and inner insulating systems and also the essential electric accessory in electric power system, especially in the high voltage engineering (AC 1000kV, DC 800kV). This paper presented the experimental research of thermal aging characteristic of oil-paper insulation used in bushing. A thermally accelerated aging experiment at 90℃ was performed. The bushing models containing five layers of paper were sealed into the aging vessels and further aged for 250 days. Then several important parameters associated with the aging were observed and evaluated. The results showed that the degree of polymerization (DP) of papers gradually decreased. The DP values of outermost layer and middle layer fit well into the second-order kinematic model and first-order kinematic model, respectively. Less deterioration speed of the inter-layer paper than outer layer was confirmed by the variation of DP. Hydrolysis was considered as the main cause to this phenomenon. In addition, the logarithm of the furfural concentrations in insulation oil was found to have good linear relationship with DP of papers. Interestingly, when the aging time is about 250 days and DP is 419, the aging process reaches an inflection point at which the DP approaches the leveling off degree of polymerization (LODP) value. Both tanδ and acid number of oils increased, while surface and volume resistivity of papers decreased. The obtained results demonstrated that thermal aging and moisture absorbed in papers brought great influence to the degradation of insulating paper, leading to rapid decrease of DP and increase of the tanδ. Thus, the bushing should be avoided from damp and real-time monitoring to the variation of tanδ and DP values of paper is an effective way to evaluate the insulation status of bushing.

Characterization of an Alien Chromosome of Oryza officinalis Transferred the Genomic and Cytological Environment of Oryza sativa

Gang Li,Ming Tang,Wei Hu,Guangcun He,Hong Liu,Xuequn Liu,Rui Qin 한국식물학회 2010 Journal of Plant Biology Vol.52 No.4

Distant hybridization between rice species and their genome interactions have become the hot points of genetic research. The new formed hybrid was unstable and many of the alien chromosomes would be excluded out in the meiosis procedure. In this study, we investigated the phenomenon that the monosomic alien addition lines (MAALs) of Oryza officinalis (CC)–Oryza sativa (AA)inherited in the genomic and cytoplasmic environments of cultivated rice. In a series of backcross programs, every time the MAALs were backcrossed with the recurrent parent Hejiang19, we get a portion of the backcross progenies that were similar to the female parent MAALs in morphological characters (with rolled leaves) and chromosome constitutions (2n+1). The monosomic alien chromosome exhibited stable inheritance in the genomic and cytoplasmic environments of cultivated rice. Molecular biology and fluorescence in situ hybridization (FISH)analyses on mitotic cells showed that the alien chromosomes in MAALs were inclined to be transferred integrated into the backcross progenies with rolled leaves and no big fragments of alien chromosomes introgressing into the chromosomes of cultivated rice. By FISH analysis on the meiotic cells, we proved that the single alien chromosome performing nonstandard meiosis and behaving like a dispensable genetic factor, which would be the cytological reasons for the stable inheritance of alien chromosomes.

Prognosis and Management for Gallbladder Cancer with Hepatic Invasion: Long-term Results of 139 Patients from a Single Center in China

Qu, Kai,Chang, Hu-Lin,Liu, Si-Nan,Liu, Chang,Xu, Xin-Sen,Wang, Rui-Tao,Zhou, Lei,Tian, Feng,Wei, Ji-Chao,Tai, Ming-Hui,Meng, Fan-Di Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.3

Objective: To improve the diagnosis of primary gallbladder carcinoma (GBC) with/without hepatic metastases by analyzing our experience of different GBC treatment in our patients. Methods: A retrospective study was carried out to analyze the clinical data of the 139 patients with GBC who underwent hepatic resection in our unit from January 2003 to December 2007. Patients were divided into two groups according to whether they demonstrated hepatic invasion. Tumor presentation, surgical modes, and prognosis of each patient were retrospectively reviewed. Kaplan-Meier curves and log-rank tests were employed to compare the survival rates of those patients undergoing different surgical procedures. Results: Of the 139 patients, 46 were men and 93 were women with the male to female ratio of 1:2.0. Their ages were ranged from 35 to 86 years with a mean age of $62.8{\pm}10.4$ years. There were 73 patients complicated with hepatic invasion (group A), and no hepatic invasion occurred in the other 66 patients (group B). Compared with the group B, the patients with hepatic invasion suffered lower differentiation of tumor (p=0.000), more advanced Nevin staging (p=0.008) and poorer prognosis (p=0.013). Radical resection were more frequently performed in group B (75.76%) than in group A (45.20%) with better outcomes (p=0.000). Conclusion: GBC patients complicated with hepatic invasion had poorer prognosis than those without invasion in long-term follow-ups. Radical resection might result in a satisfied prognosis in patients without hepatic invasion, but appears less favorable than palliative resection in those who were complicated with hepatic invasion.

The Blood Oxygenation T2* Values of Resectable Esophageal Squamous Cell Carcinomas as Measured by 3T Magnetic Resonance Imaging: Association with Tumor Stage

Yu-lian Tang,Xiao-ming Zhang,Zhi-gang Yang,Yu-cheng Huang,Tian-wu Chen,Yan-li Chen,Fan Chen,Nan-lin Zeng,Rui Li,Jiani Hu 대한영상의학회 2017 Korean Journal of Radiology Vol.18 No.4

Objective: To explore the association between the blood oxygenation T2* values of resectable esophageal squamous cell carcinomas (ESCCs) and tumor stages. Materials and Methods: This study included 48 ESCC patients and 20 healthy participants who had undergone esophageal T2*-weighted imaging to obtain T2* values of the tumors and normal esophagi. ESCC patients underwent surgical resections less than one week after imaging. Statistical analyses were performed to identify the association between T2* values of ESCCs and tumor stages. Results: One-way ANOVA and Student-Newman-Keuls tests revealed that the T2* value could differentiate stage T1 ESCCs (17.7 ± 3.3 ms) from stage T2 and T3 tumors (24.6 ± 2.7 ms and 27.8 ± 5.6 ms, respectively; all ps < 0.001). Receiver operating curve (ROC) analysis showed the suitable cutoff T2* value of 21.3 ms for either differentiation. The former statistical tests demonstrated that the T2* value could not differentiate between stages T2 and T3 (24.6 ± 2.7 ms vs. 27.8 ± 5.6 ms, respectively, p > 0.05) or between N stages (N1 vs. N2 vs. N3: 24.7 ± 6.9 ms vs. 25.4 ± 4.5 ms vs. 26.8 ± 3.9 ms, respectively; all ps > 0.05). The former tests illustrated that the T2* value could differentiate anatomic stages I and II (18.8 ± 4.8 ms and 26.9 ± 5.9 ms, respectively) or stages I and III (27.3 ± 3.6 ms). ROC analysis depicted the same cutoff T2* value of 21.3 ms for either differentiation. In addition, the Student’s t test revealed that the T2* value could determine grouped T stages (T0 vs. T1–3: 17.0 ± 2.9 ms vs. 25.2 ± 6.2 ms; T0–1 vs. T2–3: 17.3 ± 3.0 ms vs. 27.1 ± 5.3 ms; and T0–2 vs. T3: 18.8 ± 4.2 ms vs. 27.8 ± 5.6 ms, all ps < 0.001). ROC analysis indicated that the T2* value could detect ESCCs (cutoff, 20 ms), and discriminate between stages T0–1 and T2–3 (cutoff, 21.3 ms) and between T0–2 and T3 (cutoff, 20.4 ms). Conclusion: The T2* value can be an additional quantitative indicator for detecting ESCC except for stage T1 cancer, and can preoperatively discriminate between some T stages and between anatomic stages of this tumor.

Gallbladder Cancer: a Subtype of Biliary Tract Cancer Which is a Current Challenge in China

Qu, Kai,Liu, Si-Nan,Chang, Hu-Lin,Liu, Chang,Xu, Xin-Sen,Wang, Rui-Tao,Zhou, Lei,Tian, Feng,Wei, Ji-Chao,Tai, Ming-Hui,Meng, Fan-Di Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Biliary tract cancers, broadly described as malignancies that arise from the biliary tract epithelia, are usually divided into two major clinical phenotypes: cholangiocarcinoma and gallbladder cancer, differing in etiopathogenesis, risk factors, and perhaps molecular and genetic signatures. Atypical symptoms and lack of tumor biomarkers make it difficult to diagnose in early stages. At the time of presentation, few patients are candidates for potentially curative surgical resection. We here assessed and compared features of a total of 150 cases divided into extra- and intrahepatic cholangiocarcinomas and gallbladder cancers (GBC). Althought there were no significant differences in serum tumour marker levels, GBC patients had the poorest prognosis. Furthermore, gallbladder cancer respond poorly to chemotherapy or radiation therapy and approximately half of untreated patients died within 10 months. Therefore, treatment for patients with gallbladder cancer is still in challenge. Outcomes and survival of these patients had improved little over the past three decades - a period in which new successful treatments have greatly contributed to the prolonged patient survival for many other cancers.

miR-1246 inhibits NFATc1 phosphorylation and regulates Th17 cell activation in the pathogenesis of severe alopecia areata

Si-si Qi,Ying Miao,You-yu Sheng,Rui-ming Hu,Jun Zhao,Qin-ping Yang 대한피부과학회 2023 Annals of Dermatology Vol.35 No.1

Background: We found microRNA (miR)-1246 to be significantly differentially expressedbetween severe active alopecia areata (AA) patients and healthy individuals. Objective: To explore the role and mechanism of miR-1246 in severe AA. Methods: Expression of miR-1246, dual-specific tyrosine phosphorylation-regulated kinase1A (DYRK1A), and nuclear factor of activated T cells 1c (NFATc1) in peripheral CD4+ Tcells and in scalp tissues of patients were detected using RT-qPCR, Western blot, and immunohistochemistryassays. Peripheral CD4+ T cells from the AA patients were transfectedwith lentiviral vectors overexpressing miR-1246. RT-qPCR and Western blot analysis wereused to measure mRNA or protein expression of retinoic-acid-receptor-related orphan nuclearreceptor gamma (ROR-γt), interleukin (IL)-17, DYRK1A, NFATc1, and phosphorylatedNFATc1. Flow cytometry was used to assay the CD4+IL-17+ cells proportion. ELISA wasused to measure cytokine levels. Results: miR-1246 levels decreased and DYRK1A and NFATc1 mRNA levels significantlyincreased in the peripheral CD4+ T cells and scalp tissues of severe active AA samples. NFATc1 protein expression was also significantly increased in the peripheral CD4+ T cellsbut not in the scalp tissues. NFATc1 positive cells were mainly distributed among infiltratinginflammatory cells around hair follicles. In peripheral CD4+ T cells of severe active AA,overexpression of miR-1246 resulted in significant downregulation of DYRK1A, NFATc1,ROR-γt, and IL-17 mRNA and phosphorylated NFATc1 protein, as well as a decrease in theCD4+IL-17+ cells proportion and the IL-17F level. Conclusion: miR-1246 can inhibit NFAT signaling and Th17 cell activation, which may bebeneficial in the severe AA treatment.