Effect of Thermal Aging on Threshold Field Strength and Relative Permittivity of Cross-Linked Polyethylene with Different Cross-Linking Agent Contents

Wan Dai,Qi Fei,Zhou Quan,Zhou Hengyi,Zhao Miao,Duan Xujin 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.6

This article presents the eff ect of thermal aging on threshold fi eld strength and relative permittivity of cross-linked polyethylene (XLPE) with diff erent cross-linking agent contents. Here, low-density polyethylene (LDPE) and dicumyl peroxide (DCP) are used as basic experimental material and cross-linking agent, respectively. Eventually, experimental results indicate that thermal aging can gradually make threshold fi eld strength and relative permittivity of XLPE with diff erent DCP contents increase and decrease, respectively. Besides, threshold fi eld strength of XLPE with diff erent DCP contents increases fi rst and then decreases as the increase of DCP content, while relative permittivity of XLPE with diff erent DCP contents decreases fi rst and then increases as DCP content increases at diff erent thermal aging time, etc. These studies in this article are the basis of the research on space charge accumulation and dissipation inside XLPE materials, which are of great signifi cance to the normal operation of XLPE cables.

QTBiCGSTAB Algorithm for Large Linear Systemand Parallelized

Xiaomei Xu,Jilin Zhang,Jian Wan,Li Zhou,Ming Jiang 보안공학연구지원센터 2014 International Journal of Grid and Distributed Comp Vol.7 No.6

According to the traditional stabilized biconjugate gradient algorithm (BiCGSTAB) deficiency in data locality, this paper proposed a QTBiCGSTAB algorithm whose core idea is that recursively divides sparse matrix with quarter tree into sub-matrix and reorders them, to improve the hit ratio of cache and enhance the algorithm’s efficiency. And the idea is good for algorithm being parallized, that is proved by the numerical experiments later. It mainly shows, firstly, QTBiCGSTAB algorithm is more efficiency than BiCGSTAB, and the speedup would reach 1:330. The target division length would be influnced on the algorithm’s performance; Secondly, for large linear system, parallized QTBiCGSTAB is more efficiency than serial’s.

An Iterative Space Alternative Tiling Parallel Algorithm for 3D Finite Difference Stencil Computations

Jing Shen,Jilin Zhang,Jian Wan,Li Zhou,Ming Jiang 보안공학연구지원센터 2014 International Journal of Database Theory and Appli Vol.7 No.6

Stencils are finite-difference algorithms for solving large-scale and high-dimension partial differential equations. Due to the data dependences among the iterative statements in Stencils, traditional Stencil computations are be executed serially, rather than in parallel. It’s challenging to design an effective and scalable Stencil parallelized method. To address the issue of 3D data space computing, we present a serial execution model based on multi-layers symmetric Stencil method and time skewing techniques. Within this model, the iteration space is divided to multiple tiles based on time skewing, where the executive process is ordered by the sequence of tiles, and the nodes in each individual tile can be swept repeatedly to improve the data locality. In addition, we propose a novel 3D iterative space alternate tiling Stencil parallel method, which subdivides the iteration space along high dimension, and changes the execution sequence of tiles to reduce the data dependency and communication cost, where the partial order of tiles is still guaranteed. Experimental results demonstrate our proposed alternative tiling parallel method achieves better parallel efficiency and scalability compared with the domain-decomposition methods.

Linking the gut microbiota to persistent symptoms in survivors of COVID-19 after discharge

Zhou Yaya,Zhang Jianchu,Zhang Dongmei,Ma Wan-Li,Wang Xiaorong 한국미생물학회 2021 The journal of microbiology Vol.59 No.10

Several follow-up studies have found that COVID-19 (coronavirus disease 2019) patients had persistent symptoms after discharge. Gut microbiota play an important role in human health and immune responses. Therefore, this study investigated the gut microbiota of recovered COVID-19 patients and the correlations between gut microbiota and persistent symptoms after discharge. Stool samples were collected from 15 recovered healthcare workers (HCWs) with COVID-19 at three months after discharge, in addition, stool samples were collected from 14 healthy controls (HCs) to perform 16S rRNA gene sequencing between May and July 2020. Compared with HCs, recovered HCWs had reduced bacterial diversity at three months after discharge, with a significantly higher relative abundance of opportunistic pathogens, and a significantly lower relative abundance of beneficial bacteria. In addition, Escherichia unclassified was positively correlated with persistent symptoms at three months after discharge, including fatigue (r = 0.567, p = 0.028), chest tightness after activity (r = 0.687, p = 0.005), and myalgia (r = 0.523, p = 0.045). Intestinibacter bartlettii was positively correlated with anorexia (r = 0.629, p = 0.012) and fatigue (r = 0.545, p = 0.036). However, Faecalibacterium prausnitzii was negatively correlated with chest tightness after activity (r = -0.591, p = 0.02), and Intestinimonas butyriciproducens was negatively correlated with cough (r = -0.635, p = 0.011). In conclusion, the gut microbiota of recovered HCWs with COVID-19 at three months after discharge was different from that of HCs, and altered gut microbiota was correlated with persistent symptoms after discharge, highlighting that gut microbiota may play an important role in the recovery of patients with COVID-19.

Prognostic Values of Various Clinical Factors and Genetic Subtypes for Diffuse Large B-cell lymphoma Patients: A Retrospective Analysis of 227 Cases

Zhou, De,Xie, Wan-Zhuo,Hu, Ke-Yue,Huang, Wei-Jia,Wei, Guo-Qing,He, Jing-Song,Shi, Ji-Min,Luo, Yi,Li, Li,Zhu, Jing-Jing,Zhang, Jie,Lin, Mao-Fang,Ye, Xiu-Jin,Cai, Zhen,Huang, He Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.2

Aim: To analyze the significance of different clinical factors for prognostic prediction in diffuse large B-cell lymphoma (DLBCL) patients. Methods: Two hundred and twenty-seven DLBCL patients were retrospectively reviewed. Patients were managed with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) regimen or rituximab plus the CHOP (RCHOP) regimen. Results: Lactate dehydrogenase (LDH), ${\beta}2$-microglobulin (${\beta}2$-M), B symptoms, Ann Arbor stage and genetic subtypes were statistically relevant in predicting the prognosis of the overall survival (OS). In the CHOP group, the OS in patients with germinal center B-cell-like (GCB)(76.2%) was significantly higher than that of the non-GCB group (51.9%, P=0.032). With RCHOP management, there was no statistical difference in OS between the GCB (88.4%) and non-GCB groups (81.9%, P=0.288). Conclusion: Elevated LDH and ${\beta}2$-M levels, positive B symptoms, Ann Arbor stage III/IV, and primary nodal lymphoma indicate an unfavorable prognosis of DLBCL patients. Patients with GCB-like DLBCL have a better prognosis than those with non-GCB when treated with the CHOP regimen. The RCHOP treatment with the addition of rituximab can improve the prognosis of patients with DLBCL.

Synthesis of Novel Halobenzyloxy and Alkoxy 1,2,4-Triazoles and Evaluation for Their Antifungal and Antibacterial Activities

Wan, Kun,Zhou, Cheng-He Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.7

A new class of halobenzyloxy or alkoxy 1,2,4-triazoles and their hydrochlorides were synthesized through cyclization starting from commercially available phenylhydrazine. The structures were characterized by MS, IR and $^1H$ NMR spectra as well as elemental analyses. All the synthesized compounds were screened for their antibacterial activities in vitro against Staphylococcus aureus (ATCC29213), methicillin-resistant Staphylococcus aureus (N315), Bacillus subtilis, Escherichia coli (ATCC25922), Pseudomonas aeruginosa, Shigella dysenteriae, Eberthella typhosa, and antifungal activities against Candida albicans (ATCC76615), Aspergillus fumigatus by broth microdilution assay method. The results of preliminary bioassay indicated that 3-(2,4-difluorobenzyloxy)-1-phenyl-1H-1,2,4-triazole hydrochloride exhibited the best inhibitory activity with an MIC value of 56.25 ${\mu}M$ against P. aeruginosa superior to Chloramphenicol, and showed comparable activity with Chloramphenicol against E. coli (ATCC25922).

Erratum: Vitexin Inhibits Gastric Cancer Growth and Metastasis through HMGB1-mediated Inactivation of the PI3K/AKT/mTOR/HIF-1α Signaling Pathway

Zhou, Peng,Zheng, Zi-Han,Wan, Tao,Wu, Jie,Liao, Chuan-Wen,Sun, Xue-Jun The Korean Gastric Cancer Association 2022 Journal of gastric cancer Vol.22 No.2

Prognostic Value of Serum Epstein–Barr Virus Antibodies and Their Correlation with TNM Classification in Patients with Locoregionally Advanced Nasopharyngeal Carcinoma

Wan-Ru Zhang,Yu-Yun Du,Chun-Yan Guo,Han-Xing Zhou,Jie-Yi Lin,Xiao-Han Meng,Hao-Yuan Mo,Dong-Hua Luo 대한암학회 2021 Cancer Research and Treatment Vol.53 No.4

Purpose This study assessed the correlation between Epstein-Barr virus (EBV) biomarkers and the eighth American Joint Committee on Cancer staging system and the prognostic values of IgG antibodies against replication and transcription activator (Rta-IgG), IgA antibodies against Epstein-Barr nuclear antigen 1, and BamH1 Z transactivator (Zta-IgA) in locoregionally advanced nasopharyngeal carcinoma (NPC) patients. Materials and Methods Serum EBV antibody levels were measured by enzyme-linked immunosorbent assay in 435 newly diagnosed stage III-IVA NPC patients administered intensity-modulated radiation therapy±chemotherapy. The primary endpoint was progression-free survival (PFS). Results Rta-IgG and Zta-IgA levels were positively correlated with the N category and clinical stage. Patients with high Rta-IgG levels (> 29.07 U/mL) showed a significantly inferior prognosis as indicated by PFS (77% vs. 89.8%, p=0.004), distant metastasis–free survival (DMFS) (88.3% vs. 95.8%, p=0.021), and local recurrence-free survival (LRFS) (91.2% vs. 98.3%, p=0.009). High Rta-IgG levels were also significantly associated with inferior PFS and LRFS in multivariable analyses. In the low-level EBV DNA group (≤ 1,500 copies/mL), patients with high Rta-IgG levels had significantly inferior PFS and DMFS (both p < 0.05). However, in the high-level EBV DNA group, Rta-IgG levels were not significantly associated with PFS, DMFS, and LRFS. In the advanced T category (T3-4) subgroup, high Rta-IgG levels were also significantly associated with inferior PFS, DMFS, and LRFS (both p < 0.05). Conclusion Rta-IgG and Zta-IgA levels were strongly correlated with the TNM classification. Rta-IgG level was a negative prognostic factor in locoregionally advanced NPC patients, especially those with advanced T category or low EBV DNA level.

Spatial information System Applications for Sustainable Development : Theoretical and Case Studies

Wan, Chen Xiu,Jing, Li,Jun, Zhou Nai 대한원격탐사학회 1996 International Symposium on Remote Sensing Vol.12 No.1

Sustainable development is a way that will meet current needs without compromising the ability of future generations to meet their needs. It needs read-time dynamic information in various fields especially in natural resources and environment for planning and decision-making. The application of Spatial Information System(SIS) including Remote Sensing (RS), Geographical Information System (GIS), Global Positioning System (GPS) and Ground Monitoring System(GMS), etc., can obtain the dynamic information of regional resource, environment, disaster, etc. It also plays important roles in information restoring, inquiring, analyzing, and decision making. On the other hand, the social and economical development will provide farther supports for SIS technique development and applications. In this paper, the principle and methodology of SIS applying for regional sustainable development were discussed, and a case study in Panzhihua City, Sichuan Province, China was introduced.

Study of nano-SiO2 reinforced CO2 foam for anti-gas channeling with a high temperature and high salinity reservoir

Wanli Kang,Haizhuang Jiang,Hongbin Yang,Zhe Li,Bobo Zhou,Yingqi He,Bauyrzhan Sarsenbekuly,Maratbek Gabdullin 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.97 No.-

CO2 flooding has been widely applied in lots of low permeability reservoirs. After extensive CO2 injection,some reservoirs began to show serious gas channeling problems. CO2 foam had been successfully used tosolve gas channeling problems due to its advantages of water selective plugging features (not pluggingoil). In this paper, a novel CO2 foam system was developed for high temperature and high salinity(HTHS)(85 ℃, 60,000 mg/L) aiming at solving the gas channeling in Changqing Oilfield. Taking the foam half-lifeas the evaluation standard, the optimum foam system (0.5 wt% EC-1 + 1 wt% SiO2) for the target reservoirwas determined. The influences of temperature, salinity and pressure on the CO2 foam performance werestudied by high temperature and high pressure(HTHP)method. The ability and mechanism of anti-gaschanneling were studied by experiments of sand packed tube and microscopic displacement,respectively. The results showed that the foam system possessed good foam properties at HTHS withpressure. As the concentration of SiO2 nanoparticles increased, the resistance factor of the foam systemincreased. However, temperature showed an adverse effect on foam stability, the resistance factordecreased with the increase of temperature. The Jamin superposition and emulsion plugging mechanismof foam system was revealed by microscopic displacement experiments.