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.

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.

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.

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.

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.

Characteristics and Health Risks of Particulate Polycyclic Aromatic Hydrocarbons and Nitro-polycyclic Aromatic Hydrocarbons at Urban and Suburban Elementary Schools in Shanghai, China

Lulu Zhang,Takahiro Tokuda,Lu Yang,Quanyu Zhou,Xuan Zhang,Wanli Xing,Qing Wu,Zhijun Zhou,Renjie Chen,Takayuki Kameda,Akira Toriba,Kazuichi Hayakawa,Ning Tang 한국대기환경학회 2019 Asian Journal of Atmospheric Environment (AJAE) Vol.13 No.4

PM2.1 was collected at urban and suburban elementary schools in Shanghai during two sampling periods in cold and warm seasons in 2007. Nine polycyclic aromatic hydrocarbons (PAHs) and ten nitro-polycyclic aromatic hydrocarbons (NPAHs) in PM2.1 were determined. During both seasons, the concentrations of PAHs and NPAHs at urban and suburban schools were not significantly different (p>0.05) and were higher in the cold period than in the warm period. According to the diagnostic ratios, PAHs and NPAHs at both schools were subject to the mixed effects of vehicle emission and coal combustion during both periods. Moreover, the results of the backward trajectory showed that PAHs and NPAHs were more susceptible to external polluted air masses in the cold period. At both urban and suburban schools, the inhalation cancer risk of PAHs and NPAHs in PM2.1 for children during elementary period was dozens of times of the acceptable risk level regulated by the U.S.EPA, highlighting the adverse impact of exposure to PAHs and NPAHs on the healthy development of children.

Enhanced postoperative cancer therapy by iron-based hydrogels

Haomeng Zhang,Meng Zhang,Xinyu Zhang,Yuan Gao,Yanling Ma,Hongyu Chen,Jipeng Wan,Changzhong Li,Fei Wang,Xiao Sun 한국생체재료학회 2022 생체재료학회지 Vol.26 No.2

Surgical resection is a widely used method for the treatment of solid tumor cancers. However, the inhibition of tumor recurrence and metastasis are the main challenges of postoperative tumor therapy. Traditional intravenous or oral administration have poor chemotherapeutics bioavailability and undesirable systemic toxicity. Polymeric hydrogels with a three-dimensional network structure enable on-site delivery and controlled release of therapeutic drugs with reduced systemic toxicity and have been widely developed for postoperative adjuvant tumor therapy. Among them, because of the simple synthesis, good biocompatibility, biodegradability, injectability, and multifunctionality, ironbased hydrogels have received extensive attention. This review has summarized the general synthesis methods and construction principles of iron-based hydrogels, highlighted the latest progress of iron-based hydrogels in postoperative tumor therapy, including chemotherapy, photothermal therapy, photodynamic therapy, chemo-dynamic therapy, and magnetothermal-chemical combined therapy, etc. In addition, the challenges towards clinical application of iron-based hydrogels have also been discussed. This review is expected to show researchers broad perspectives of novel postoperative tumor therapy strategy and provide new ideas in the design and application of novel iron-based hydrogels to advance this sub field in cancer nanomedicine.

The mitochondrial genome of the Kentish Plover Charadrius alexandrinus (Charadriiformes: Charadriidae) and phylogenetic analysis of Charadrii

Wan Chen,Chenling Zhang,Tao Pan,Wei Liu,Kexin Li,Chaochao Hu,Qing Chang 한국유전학회 2018 Genes & Genomics Vol.40 No.9

The suborder Charadrii (Aves: Charadriiformes), one of the most species-rich radiations within shorebirds, which contains good source for studies of ecology, behaviour and evolution. The resources of mitogenome have rapidly accumulated in recent years due to the advanced genomic sequencing, while suborder Charadrii’s mitogenome has not been well studied. The primary objective of this study was to determine the complete mitogenome sequence of Charadrius alexandrinus, and investigated the evolutionary relationship within Charadrii. The mitogenome of C. alexandrinus were generated by amplification of overlapping Polymerase Chain Reaction (PCR) fragments. In this study, we determined the complete mitogenome sequence of the Kentish Plover Charadrius alexandrinus, and comparative analysed 11 species to illustrate mitogenomes structure and investigated their evolutionary relationship within Charadrii. The Charadrii mitogenomes displayed moderate size variation, the mean size was 16,944 bp (SD = 182, n = 11), and most of the size variation due to mutations in the control region (CR). Nucleotide composition was consistently biased towards AT rich, and the A+T content also varies for each protein-coding genes. The variation in ATP8 and COIII was the highest and lowest respectively. The GC skew was always negative, with the ATP8 had higher value than other regions. The average uncorrected pairwise distances revealed heterogeneity of evolutionary rate for each gene, the COIII, COI and COII have slow evolutionary rate, whereas the gene of ATP8 has the relative fast rate. The highest value of Ks and Ka were ND1 and ATP8, and the ratios of Ka/Ks are lower than 0.27, indicating that they were under purifying selection. Phylogenomic analysis based on the complete mitochondrial genomes strongly supported the monophyly of the suborder Charadrii. This study improves our understanding of mitogenome structure and evolution, and providing further insights into phylogeny and taxonomy in Charadrii. In future, sequencing more mitogenomes from various taxonomic levels will significantly improve our understanding of phylogenetic relationships within Charadrii.

Genetic Variations in the HIF1A Gene Modulate Response to Adjuvant Chemotherapy after Surgery in Patients with Colorectal Cancer

Zhang, Yi,Wang, Peng,Zhou, Xing-Chun,Bao, Guo-Qiang,Lyu, Zhuo-Ming,Liu, Xiao-Nan,Wan, Shao-Gui,He, Xian-Li,Huang, Qi-Chao Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.11

Background: Hypoxia-inducible factor $1{\alpha}$ (HIF-$1{\alpha}$) plays an important role in regulating cell survival and angiogenesis, which are critical for tumor growth and metastasis. Genetic variations of HIF1A have been shown to influence the susceptibility to many kinds of human tumors. Increased expression of HIF-$1{\alpha}$ has also been demonstrated to be involved in tumor progression. However, the prognostic value of single nucleotide polymorphisms (SNPs) inthe HIF1A gene remains to be determined in most cancer types, including colorectal cancer (CRC). In this study, we sought to investigate the predictive role of HIF1A SNPs in prognosis of CRC patients and efficacy of chemotherapy. Materials and Methods: We genotyped two functional SNPs in HIF1A gene using the Sequenom iPLEX genotyping system and then assessed their associations with clinicopathological parameters and clinical outcomes of 697 CRC patients receiving radical surgery using Cox logistic regression model and Kaplan Meier curves. Results: Generally, no significant association was found between these 2 SNPs and clinical outcomes of CRC. In stratified analysis of subgroup without adjuvant chemotherapy, patients carrying CT/TT genotypes of rs2057482 exhibited a borderline significant association with better overall survival when compared with those carrying CC genotype [Hazard ratio (HR), 0.47; 95% confidence interval (95% CI): 0.29-0.76; P < 0.01]. Moreover, significant protective effects on CRC outcomes conferred by adjuvant chemotherapy were exclusively observed in patients carrying CC genotype of rs2057482 and in those carrying AC/CC genotype of rs2301113. Conclusions: Genetic variations in HIF1A gene may modulate the efficacy of adjuvant chemotherapy after surgery in CRC patients.

Impact of numerical choices on water conservation in the E3SM Atmosphere Model version 1 (EAMv1)

Zhang, Kai,Rasch, Philip J.,Taylor, Mark A.,Wan, Hui,Leung, Ruby,Ma, Po-Lun,Golaz, Jean-Christophe,Wolfe, Jon,Lin, Wuyin,Singh, Balwinder,Burrows, Susannah,Yoon, Jin-Ho,Wang, Hailong,Qian, Yun,Tang, Q Copernicus GmbH 2018 Geoscientific model development Vol.11 No.5

<P><p><strong>Abstract.</strong> The conservation of total water is an important numerical feature for global Earth system models. Even small conservation problems in the water budget can lead to systematic errors in century-long simulations. This study quantifies and reduces various sources of water conservation error in the atmosphere component of the Energy Exascale Earth System Model.</p> <p>Several sources of water conservation error have been identified during the development of the version 1 (V1) model. The largest errors result from the numerical coupling between the resolved dynamics and the parameterized sub-grid physics. A hybrid coupling using different methods for fluid dynamics and tracer transport provides a reduction of water conservation error by a factor of 50 at 1<span class='inline-formula'>^∘</span> horizontal resolution as well as consistent improvements at other resolutions. The second largest error source is the use of an overly simplified relationship between the surface moisture flux and latent heat flux at the interface between the host model and the turbulence parameterization. This error can be prevented by applying the same (correct) relationship throughout the entire model. Two additional types of conservation error that result from correcting the surface moisture flux and clipping negative water concentrations can be avoided by using mass-conserving fixers. With all four error sources addressed, the water conservation error in the V1 model becomes negligible and insensitive to the horizontal resolution. The associated changes in the long-term statistics of the main atmospheric features are small.</p> <p>A sensitivity analysis is carried out to show that the magnitudes of the conservation errors in early V1 versions decrease strongly with temporal resolution but increase with horizontal resolution. The increased vertical resolution in V1 results in a very thin model layer at the Earth's surface, which amplifies the conservation error associated with the surface moisture flux correction. We note that for some of the identified error sources, the proposed fixers are remedies rather than solutions to the problems at their roots. Future improvements in time integration would be beneficial for V1.</p> </P>