YAG 결정에 첨가된 Tm^3+와 Ho^3+이온의 형광 메카니즘 분석

장만송,서효진 釜慶大學校 2001 釜慶大學校 論文集 Vol.6 No.-

The fluorescence characteristics of Tm3+ and Ho3+ ions in YAG crystal were investi- gated by using the high-resolution laser spectroscopy. The emission, excitation, power dependence and lifetime measurements were performed. The upconverted and downconverted fluorescence in the range from IR to UV were observed under the excitation into the 3F2 state of Tm3+ and the 5F5 state of Ho3+. The sequential two- photon excitation process (STEP) and energy transfer upconversion (ETU) are dominant mechanisms for the upconversion fluorescence in this system.

A SECURITY DV-Hop Localization Algorithm Resist Spoofing Attack

Wanli ZHANG,Qixiang SONG 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.11

In order to reduce the node position error of DV-Hop algorithm in wireless sensor network, the artificial bee colony algorithm is introduced to design the DV-Hop algorithm. A new ABCDV-Hop (Artificial Bee Colony DV-Hop) algorithm is proposed in this paper. Based on the traditional DV-Hop algorithm, by using the minimum hops of nodes and position information of anchor nodes, the average distance per hop is solved by artificial bee colony algorithm to make it more close to the actual value. The simulation results show that compared with the traditional DV-Hop algorithm, the improved algorithm can effectively reduce the positioning error without increasing the node hardware overhead.

Experimental identification of fluid-induced force in labyrinth seals

Wan Fu Zhang,Jian Gang Yang,Hao Cao,Dan Sun 대한기계학회 2011 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.25 No.10

The seal force is an important factor in turbomachineries. Therefore, the current paper puts forward an expanded seal force identification model. A seal test rig consisting of several sets of seals was prepared. Using the double-plane unbalance force identification theory in rotordynamics, the distributed seal force in the cylinder became equivalent to two selected planes. Considering the complex cylinder vibration with increasing rotating speed and inlet pressure, the cylinder was regarded as a vibration system with 4 degrees of freedom. The 4×4 impedance matrix was tested at the two selected planes using a shaker in two orthogonal directions. The equivalent seal force can be obtained by multiplying the impedance matrix with the measured change in the cylinder vibration. In the seal rig, tests were performed on the influence of inlet pressure, rotating speed, eccentricity ratio, rotor vibration, and clearance. The seal force increases almost linearly with the increasing inlet pressure, eccentricity ratio, and vibration amplitude. Furthermore, the seal force is strongly sensitive to the change in clearance between the cylinder and the rotating rotor. The phase difference between the seal force and the vibration influences the work done. If the phase difference is nearly 90°, then the work is at maximum. Moreover, the seal force applies positive force on the cylinder and negative force on the rotor.

Potential Therapeutic Targets for the Primary Gallbladder Carcinoma: Estrogen Receptors

Zhang, Ling-Qiang,Zhang, Xiu-De,Xu, Jia,Wan, Yong,Qu, Kai,Zhang, Jing-Yao,Wang, Zhi-Xin,Wei, Ji-Chao,Meng, Fan-Di,Tai, Ming-Hui,Zhou, Lei,Liu, Chang Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

Gallbladder carcinoma, the most frequent malignant neoplasm of the biliary tract system, has always been considered to feature late clinical presentation and diagnosis, limited treatment options and an extremely poor prognosis. In recent years, while the incidence of gallbladder cancer has appeared to be on the increase, the available treatment methods have not greatly improved survival of the affected patients. Thus, exploring new therapeutic targets for this devastating disease is an urgent matter at present. Epidemical studies have demonstrated that the incidence of gallbladder carcinoma exhibits a distinct gender bias, affecting females two to three times more than males, pointing to crucial roles of estrogen. It is well known that estrogen acts on target tissues by binding to estrogen receptors (ERs), which are mainly divided into three subtypes, $ER{\alpha}$, $ER{\beta}$ and $ER{\gamma}$. $ER{\alpha}$ and $ER{\beta}$ appear to have overlapping but also unique even opposite biological effects. As important pathogenic mediators, ERs have been considered to relate to several kinds of tumors. In gallbladder carcinoma tissue, ERs have been shown to be positively expressed, and ERs expression levels are associated with differentiation and prognosis of this cancer. Nevertheless, the exact mechanisms of estrogen inducing growth of gallbladder carcinoma remain poorly understood. On the base of the current investigations, we deduce that estrogen participates in promotion of gallbladder carcinoma by influencing the formation of gallstones, stimulating angiogenesis, and promoting abnormal proliferation. Since ERs mediate the carcinogenic actions of estrogen in gallbladder, and therapy targeting ERs may provide new directions for gallbladder carcinoma. Therefore, it should be stressed that ERs are potential therapeutic targets for gallbladder carcinoma.

Effect of Diallyl Trisulfide on Human Ovarian Cancer SKOV-3/DDP Cell Apoptosis

Wan, Hui-Fang,Yu, Le-Han,Wu, Jin-Lan,Tu, Shuo,Zhu, Wie-Feng,Zhang, Xia-Li,Wan, Fu-Sheng Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Aim: To investigate the effects of diallyl trisulfide (DT) on apoptosis of cisplatin (DDP)-resistant human epithelial ovarian cancer SKOV-3 cells (SKOV-3/DDP), and the role of p53 upregulated modulator of apoptosis (PUMA). Methods: SKOV-3/DDP cells were randomly divided into control, DT, DPP and DPP+DT groups, which were treated with DT or combined DT and DDP. All cells were incubated for 48 h. and apoptosis rates were assessed by flow cytometry. mRNA and protein expression of PUMA, Bax and Bcl-2 was determined by RT-PCR and Western blot assays, respectively. Results: Compared with control group, the apoptosis rates of SKOV-3/DDP cells in DT groups were obviously increased, with dose-dependence (P < 0.05), the mRNA and protein expressions of PUMA, Bax also being up-regulated (P < 0.05), while those of Bcl-2 were down-regulated (P < 0.05). Compared with DT groups, the apoptosis rate in the DDP+DT group was significantly increased (P < 0.05). After knockdown of PUMA with specific siRNA, the apoptosis rate of SKOV-3/DDP cells was obviously decreased (P < 0.05). Conclusion: DT can promote the apoptosis of SKOV-3/DDP cells with PUMA playing a critical role.

ATAD2 is Highly Expressed in Ovarian Carcinomas and Indicates Poor Prognosis

Wan, Wei-Na,Zhang, Yi-Xia,Wang, Xue-Mei,Liu, Yan-Jun,Zhang, Yu-Qin,Que, Yan-Hong,Zhao, Wen-Jing Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.6

The purpose of this study was to explore the expression of ATAD2 in ovarian tumor tissue as well as its relationship with degree of malignancy. Tumor tissue from 110 cases of ovarian cancer was collected in accordance with the Declaration of Helsinki for evaluation of ATAD2 expression iimmunohistochemistry, quantitative PCR (qPCR) and Western blotting. The correlation between the ATAD2 expression and and the prognosis of ovarian cancer was evaluated by Cox regression model. In addition, HO-8910 and OVCAR-3 cells were transfected with two siRNAs targeting ATAD2. Cell viability was evaluated with MTT assay, and cell migration by transwell migration assay. ATAD2 was shown to be highly expressed in 65.5% (72/110) of ovarian cancer cases, both at transcriptional and protein levels. Moreover, highly expression was positively correlated with degree of malignancy. Knock-down of ATAD2 in HO-8910 and OVCAR-3 cells was found to reduce cell migration. In addition, follow-up visits of the patients demonstrated that the 5-year survival rate was lower in patients with high expression of ATAD2. Our study suggested that ovarian tumor tissue may have highly expressed ATAD2, which is associated with tumor stage, omentum-metastasis, ascites and CA-125. Increased ATAD2 may play important roles in tumor proliferation and migration. ATAD2 could serve in particular as a prognostic marker and a therapeutic target for ovarian cancer.

Anomalous magnetization jumps in granular Pb superconducting films

Zhang An-Lei,Jiang Wan-Yan,Chen Xing-Hong,Zhang Xiao-Ke,Lu Wen-Lai,Chen Fei,Feng Zhen-Jie,Cao Shi-Xun,Zhang Jin-Cang,Ge Jun-Yi 한국물리학회 2022 Current Applied Physics Vol.35 No.-

In granular superconductors, the grain boundaries are closely related to the vortex dynamics and the macroscopic superconducting properties. In our research, Pb films with different grain sizes were prepared by tuning the substrate temperature. With the grain size decreasing, Pb films are prone to feature the anomalous magnetization jumps in the M − T curves, while in the M − H curves flux avalanche happens. Both phenomena appear in the same region of the H − T phase diagram and thus are considered to have the same origin. The further theoretical analysis shows that with grain size decreasing the pinning mechanism evolves from a mixed δTc and δl pinning to the δl pinning mechanism. The results shed light on the study of pinning mechanism for granular superconductors and is beneficial to the potential application of manipulating vortex pinning by regulation of intrinsic defects.

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.

Clone and Identification of Bifunctional Δ12/Δ15 Fatty Acid Desaturase LKFAD15 from Lipomyces kononenkoae

Zhang Yan,Liang Zhuo,Jiang Mulan,Wan Xia,Gon Yangmin,Zhang Yinbo,Huang Fenghong 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.2

In modern diet of human being, the ω-6/ω-3ratio of dietary fatty acid was shifted much towards ω-6series. In this work, a fatty acid desaturase (FAD) gene lkfad15 was cloned and identified from oleaginous yeast Lipomyces kononenkoae. Function analysis results shown that LKFAD15 is a novel Δ12/Δ15 bifunctional FAD which could not only produce linoleic acid and α-linolenic acid use just oleic acid as substrate but also adjust the ω-6/ω-3 fatty acids ratio to the WHO recommended ratio. Phylogenetic analysis of LKFAD15 suggested it is a specific intermediate product of gene evolution derives from independent gene duplication events.

Finite-time Synchronization of Neural Networks with Multiple Proportional Delays via Non-chattering Control

Wanli Zhang,Chuandong Li,Tingwen Huang,Junjian Huang 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.5

This paper investigates finite-time synchronization of neural networks (NNs) with multiple proportional delays. In order to cope with the difficulties induced by multiple proportional delays, suitable nonlinear variable transformations and new 1-norm-based analytical techniques are developed. By constructing Lyapunov functional and designing new designed controllers, several new sufficient conditions are derived to realize synchronization in finite time. Moreover, estimation of the upper bound of synchronization time is also provided for NNs with bounded delays or proportional delays. The designed controllers without sign function are simple, which means the chattering phenomenon in most of the existing results can be overcome. A numerical simulation is offered to verify the effectiveness of the theoretical analysis.