Compact Dual-Mode Balun Bandpass Filter with Improved Out-of-Band Performance

Gao Shan Shan,Yi Gang Yu,Sun Sheng 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.4

A compact dual-mode balun bandpass fi lter with improved out-of-band performance is proposed based on a ring resonator. In order to excite the two degenerate modes and obtain fi ltering balun performance, three parallel-coupled lines are placed at three excitation ports along the ring resonator. By properly arranging the angles between the excitation arms, four transmission zeros can be realized to improve stopband performance. Finally, a prototype of the designed balun bandpass fi lter is implemented and fabricated. The measured results show a good agreement with those obtained from the simulation, thus verifying our proposal with good in-band fi ltering and out-of-band performance.

A sigma class glutathione S-transferase gene regulated by the CncC pathway is required for phytochemical tolerance in the red flour beetle, Tribolium castaneum

Gao Shan-shan,Li Dong-yu,Huo Zhuang-kun,Zhang Yong-lei,Cao Yi-zhuo,Tan Yue-yao,Guo Xin-long,Zhang Jia-hao,Zhang Kun-peng,Li Rui-min 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.4

Insect glutathione S-transferases (GSTs) play a crucial role in the detoxification of exogenous compounds, especially insecticides and plant allelochemicals. A sigma class GST gene, TcGSTS7, mediates the response to eugenol in Tribolium castaneum. However, the mechanism underlying this effect remains largely unknown. In this study, TcGSTS7, which exhibits a structural motif and domain organization characteristic of GSTs, was cloned from the T. castaneum genome. Spatiotemporal expression analysis revealed that TcGSTS7 was most highly expressed at the late larva stage and was mainly expressed in the fat body and epidermis of larvae and adults, suggesting that TcGSTS7 may play a potential role in the protection against toxic xenobiotics in T. castaneum. Furthermore, the expression of TcGSTS7 was significantly induced after exposure to eugenol, while RNA inter ference (RNAi) targeting TcGSTS7 enhanced the sensitivity of the beetle to eugenol, indicating that TcGSTS7 is involved in the tolerance of T. castaneum to this insecticide. Interestingly, the depletion of TcCncC, which encodes a transcription factor of the CncC pathway that has been associated with the regulation of detoxification-related genes in insects, led to a reduction in the TcGSTS7 transcript level following exposure to eugenol, which suggests that TcGSTS7 acts downstream of the CncC pathway. Combined, these results indicated that TcGSTS7 partici pates in the tolerance of T. castaneum to phytochemicals in a CncC pathway-dependent manner. These findings have implications for the development of novel drugs for use in pest control.

Isolation and identification of a canine coronavirus strain from giant pandas (Ailuropoda melanoleuca)

Feng-Shan Gao,Xian-zhu Xia,Yu-Wei Gao,Ya-Duo Bai,Xiao-Huan Zou,Gui-Xue Hu 대한수의학회 2009 Journal of Veterinary Science Vol.10 No.3

Two giant pandas (Ailuropoda melanoleuca) died of unknown causes in a Chinese zoo. The clinical disease profile suggested that the pandas may have suffered a viral infection. Therefore, a series of detection including virus isolation, electron microscopy, cytobiological assay, serum neutralization and RT-PCR were used to identify the virus. It was determined that the isolated virus was a canine coronavirus (CCV), on the basis of coronavirus, neutralization by canine anti-CCV serum, and 84.3% to 100% amino acid sequence similarity with CCV. The results suggest that the affected pandas had been infected with CCV.

Wavelet Multiresolution Complex Network for Analyzing Multivariate Nonlinear Time Series

Gao, Zhong-Ke,Li, Shan,Dang, Wei-Dong,Yang, Yu-Xuan,Do, Younghae,Grebogi, Celso World Scientific 2017 International journal of bifurcation and chaos in Vol.27 No.8

<P>Characterizing complicated behavior from time series constitutes a fundamental problem of continuing interest and it has attracted a great deal of attention from a wide variety of fields on account of its significant importance. We in this paper propose a novel wavelet multiresolution complex network (WMCN) for analyzing multivariate nonlinear time series. In particular, we first employ wavelet multiresolution decomposition to obtain the wavelet coefficients series at different resolutions for each time series. We then infer the complex network by regarding each time series as a node and determining the connections in terms of the distance among the feature vectors extracted from wavelet coefficients series. We apply our method to analyze the multivariate nonlinear time series from our oil-water two-phase flow experiment. We construct various wavelet multiresolution complex networks and use the weighted average clustering coefficient and the weighted average shortest path length to characterize the nonlinear dynamical behavior underlying the derived networks. In addition, we calculate the permutation entropy to support the findings from our network analysis. Our results suggest that our method allows characterizing the nonlinear flow behavior underlying the transitions of oil-water flows.</P>

Growth Inhibitory and Pro-Apoptotic Effects of Hirsuteine in Chronic Myeloid Leukemia Cells through Targeting Sphingosine Kinase 1

Gao Shan,Guo Tingting,Luo Shuyu,Zhang Yan,Ren Zehao,Lang Xiaona,Hu Gaoyong,Zuo Duo,Jia Wenqing,Kong Dexin,Yu Haiyang,Qiu Yuling 한국응용약물학회 2022 Biomolecules & Therapeutics(구 응용약물학회지) Vol.30 No.6

Chronic myeloid leukemia (CML) is a slowly progressing hematopoietic cell disorder. Sphingosine kinase 1 (SPHK1) plays established roles in tumor initiation, progression, and chemotherapy resistance in a wide range of cancers, including leukemia. However, small-molecule inhibitors targeting SPHK1 in CML still need to be developed. This study revealed the role of SPHK1 in CML and investigated the potential anti-leukemic activity of hirsuteine (HST), an indole alkaloid obtained from the oriental plant Uncaria rhynchophylla, in CML cells. These results suggest that SPHK1 is highly expressed in CML cells and that overexpression of SPHK1 represents poor clinical outcomes in CML patients. HST exposure led to G2/M phase arrest, cellular apoptosis, and downregulation of Cyclin B1 and CDC2 and cleavage of Caspase 3 and PARP in CML cells. HST shifted sphingolipid rheostat from sphingosine 1-phosphate (S1P) towards the ceramide coupled with a marked inhibition of SPHK1. Mechanistically, HST significantly blocked SPHK1/S1P/S1PR1 and BCR-ABL/PI3K/Akt pathways. In addition, HST can be docked with residues of SPHK1 and shifts the SPHK1 melting curve, indicating the potential protein-ligand interactions between SPHK1 and HST in both CML cells. SPHK1 overexpression impaired apoptosis and proliferation of CML cells induced by HST alone. These results suggest that HST, which may serve as a novel and specific SPHK1 inhibitor, exerts anti-leukemic activity by inhibiting the SPHK1/S1P/ S1PR1 and BCR-ABL/PI3K/Akt pathways in CML cells, thus conferring HST as a promising anti-leukemic drug for CML therapy in the future.

Synthesis of 8-Alkoxy-4,5-dihydro-[1,2,4]triazole[4,3-a]quinoline-1-ones and Evaluation of their Anticonvulsant Properties

Xian-Yu Sun,Yun-Zhe Jin,Fu-Nan Li,Gao Li,Kyu-Yun Chai,Zhe-Shan Quan 대한약학회 2006 Archives of Pharmacal Research Vol.29 No.12

A series of 8-alkoxy-4,5-dihydro-[1,2,4]triazole[4,3-a]quinoline-1-one derivatives were synthesized using 7-hydroxy-3,4-dihydro-2(1H)-quinolone as the starting material. Their anticonvulsant activities were evaluated by the maximal electroshock test (MES) and the subcutaneous pentylenetetrazole test (sc-PTZ), and their neurotoxicities were measured by the rotarod neurotoxicity test (Tox). The tests demonstrated that 8-hexyloxy-4,5-dihydro-[1.2.4]triazole[4.3- a]quinoline-1-one (4e) and 8-heptyloxy-4,5-dihydro-[1,2,4] triazole[4,3-a]quinoline-1-one (4f) were the most potent anticonvulsants, with 4e having ED50 values of 17.17 mg/kg and 24.55 mg/kg and protective index (PI = TD50/ED50) values of 41.9 and 29.3 in the MES and sc-PTZ tests, respectively, and 4f having ED50 values of 19.7 mg/kg and 21.2 mg/kg and PI values of 36.5 and 33.9 in the MES and sc-PTZ tests, respectively. The PI values of 4e and 4f were many fold better than that of the marketed drugs phenytoin, carbamazepine, phenobarbital and valproate, which have PI values in the range of 1.6-8.1 in the MES test and <0.22-5.2 in the sc-PTZ test. Structure-activity relationships were also discussed.

과제중심 교수법을 활용한 한국어 담화표지 ‘그냥’ 교육 연구 -중국인 학습자를 위하여 -

고산 ( Gao Shan ),박덕유 ( Park Deok-yu ) 아시아문화학술원 2017 인문사회 21 Vol.8 No.5

본고는 한국어 구어 담화에서 빈번하게 사용되는 담화표지 ‘그냥’의 기능 및 대응되는 중국어 표현, 그리고 한국어 학습자의 학습 자료와 모국어 화자의 발화 자료를 비교·분석함으로써 과제중심 교수법을 활용하여 효율적으로 배울 수 있는 교육 방안을 제시하는 데에 목적이 있다. 이에 각 기능에 대응되는 중국어 표현을 찾고, 그 기능에 따라 모국어 화자의 발화에서 사용된 빈도와 학습 자료에서 제시된 빈도를 비교해서 학습자료의 문제점을 제시하였으며 의사소통적 교수법인 과제중심 교수법을 활용한 교수 방안을 제안하였다. 따라서 중국인 학습자들이 한국어 담화표지를 학습할 때보다 효율적인 학습을 할 수 있다는 점에서 본고의 의의가 있다. The purpose of this study was to suggest an effective teaching method to help Korean learners to understand the use of Korean discourse markers more successful. In order to accomplish this research purpose, I first research the discourse functions of the marker ‘keunyang’, examined along with examples in actual conversation and the differences and similarities of correspondence expressions in Chinese. After having discussed the discourse functions, I discussed the problem of Korean Teaching materials through the comparison between the native Korean speaker’s conversation data and the textbook. Finally, I suggested a Task-Based Teaching Method in Discourse Marker ‘keunyang’ to solve the problem of Korean Teaching materials. Therefore, it is meaningful for chinese leaners that they can learn the Korean discourse markers effectively.

Inhibition of chromosomal region maintenance 1 suppresses the migration and invasion of glioma cells via inactivation of the STAT3/MMP2 signaling pathway

Qianqian Shan,Shengsheng Li,Qiyu Cao,Chenglong Yue,Mingshan Niu,Xiangyu Chen,Lin Shi,Huan Li,Shangfeng Gao,Jun Liang,Rutong Yu,Xuejiao Liu 대한생리학회-대한약리학회 2020 The Korean Journal of Physiology & Pharmacology Vol.24 No.3

Chromosomal region maintenance 1 (CRM1) is associated with an adverse prognosis in glioma. We previously reported that CRM1 inhibition suppressed glioma cell proliferation both in vitro and in vivo. In this study, we investigated the role of CRM1 in the migration and invasion of glioma cells. S109, a novel reversible selective inhibitor of CRM1, was used to treat Human glioma U87 and U251 cells. Cell migration and invasion were evaluated by wound-healing and transwell invasion assays. The results showed that S109 significantly inhibited the migration and invasion of U87 and U251 cells. However, mutation of Cys528 in CRM1 abolished the inhibitory activity of S109 in glioma cells. Furthermore, we found that S109 treatment decreased the expression level and activity of MMP2 and reduced the level of phosphorylated STAT3 but not total STAT3. Therefore, the inhibition of migration and invasion induced by S109 may be associated with the downregulation of MMP2 activity and expression, and inactivation of the STAT3 signaling pathway. These results support our previous conclusion that inhibition of CRM1 is an attractive strategy for the treatment of glioma.

Optimal feedrate planning on a five-axis parametric tool path with global geometric and kinematic constraints

Ma Hong-Yu,Yuan Chun-Ming,Shen Li-Yong,Gao Xiao-Shan 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.6

The optimal feedrate planning problem for the five-axis parametric tool path remains challenging due to the nonlinear relationships between the joint space and the Cartesian space. We present a novel and complete optimal feedrate planning method for a five-axis parametric tool path by constraining the velocity, acceleration, jerk in the joint space, and the chord error in the Cartesian space. Our method formulates the problem as an optimal control problem, and we propose an iteration control vector parametrization method to compute the optimal solution. Compared with the new development five-axis feedrate planning methods, our solution satisfies “bang-bang” optimal control, and each constraint is strictly under the limits globally. Examples and comparisons with two other methods are demonstrated to show the effectiveness of the algorithm.

Synthesis of 8-Alkoxy-4,5-dihydro-[1,2,4]triazole[4,3-a]quinoline-1-ones and Evaluation of their Anticonvulsant Properties

Sun, Xian-Yu,Jin, Yun-Zhe,Li, Fu-Nan,Li, Gao,Chai, Kyu-Yun,Quan, Zhe-Shan The Pharmaceutical Society of Korea 2006 Archives of Pharmacal Research Vol.29 No.12

A series of 8-alkoxy-4,5-dihydro-[1,2,4]triazole[4,3-a]quinoline-1-one derivatives were synthesized using 7-hydroxy-3,4-dihydro-2(1H)-quinolone as the starting material. Their anticonvulsant activities were evaluated by the maximal electroshock test (MES) and the subcutaneous pentylenetetrazole test (sc-PTZ), and their neurotoxicities were measured by the rotarod neurotoxicity test (Tox). The tests demonstrated that 8-hexyloxy-4,5-dihydro-[1.2.4]triazole[4.3-a]quinoline-1-one (4e) and 8-heptyloxy-4,5-dihydro-[1,2,4]triazole[4, 3-a]quinoline-1-one (4f) were the most potent anticonvulsants, with 4e having $ED_{50}$ values of 17.17 mg/kg and 24.55 mg/kg and protective index ($PI=TD_{50}/ED_{50}$) values of 41.9 and 29.3 in the MES and sc-PTZ tests, respectively, and 4f having $ED_{50}$ values of 19.7 mg/kg and 21.2 mg/kg and PI values of 36.5 and 33.9 in the MES and sc-PTZ tests, respectively. The PI values of 4e and 4f were many fold better than that of the marketed drugs phenytoin, carbamazepine, phenobarbital and valproate, which have PI values in the range of 1.6-8.1 in the MES test and <0.22-5.2 in the sc-PTZ test. Structure-activity relationships were also discussed.