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      • KCI등재

        A New ent-Kaurane type Diterpenoid Glycoside from Inula japonica Thunb

        Jiang Jiang Qin,Jia Xian Zhu,Wei Dong Zhang1,2,Yan Zhu,Jian Jun Fu,Xiao Hua Liu,Hui Zi Jin 대한약학회 2009 Archives of Pharmacal Research Vol.32 No.10

        A new ent-kaurane type diterpenoid glycoside, 17-O-β-D-glucopyranosyl-16α-ent-kauran-19-oic acid (1), together with 17-hydroxy-16α-ent-kauran-19-oic acid (2), 16α,17-dihydroxyl-ent-kauran-19-oic acid (3), and 16α-hydroxy-17-acetoxy-ent- kauran-19-oic acid (4) were isolated from the aerial parts of Inula japonica Thunb. The structure of 1 was determined mainly by use of 1D and 2D NMR spectroscopic techniques including HSQC, 1H-1H COSY, HMBC, and NOESY. In addition, 4 exhibited significant inhibitory activity on NO production in LPS-stimulated RAW264.7 cells with IC50 value of 14.3 μg/mL.

      • KCI등재

        Which Indicator Among Lumbar Vertebral Hounsfield Unit, Vertebral Bone Quality, or Dual-Energy X-Ray Absorptiometry-Measured Bone Mineral Density Is More Efficacious in Predicting Thoracolumbar Fragility Fractures?

        Bo Zhang,Lu-Ping Zhou,Xian-Liang Zhang,Dui Li,Jia-Qi Wang,Chong-Yu Jia,Hua-Qing Zhang,Liang Kang,Ren-Jie Zhang,Cai-Liang Shen 대한척추신경외과학회 2023 Neurospine Vol.20 No.4

        Objective: Hounsfield units (HU), vertebral bone quality (VBQ), and bone mineral density (BMD) can all serve as predictive indicators for thoracolumbar fragility fractures. This study aims to explore which indicator provides better risk prediction for thoracolumbar fragility fractures. Methods: Patients who have received medical attention from The First Affiliated Hospital of Anhui Medical University for thoracolumbar fragility fractures were selected. A total of 78 patients with thoracolumbar fragility fractures were included in the study. To establish a control group, 78 patients with degenerative spinal diseases were matched to the fracture group on the basis of gender, age, and body mass index. The lumbar vertebral HU, the VBQ, and the BMD were obtained for all the 156 patients through computed tomography, magnetic resonance imaging, and dual-energy x-ray absorptiometry (DEXA). The correlations among these parameters were analyzed. The area under curve (AUC) analysis was employed to assess the predictive efficacy and thresholds of lumbar vertebral HU, VBQ, and BMD in relation to the risk of thoracolumbar fragility fractures. Results: Among the cohort of 156 patients, lumbar vertebral HU exhibited a positive correlation with BMD (p < 0.01). Conversely, VBQ showed a negative correlation with HU, BMD (p < 0.05). HU and BMD displayed a favorable predictive efficacy for thoracolumbar fragility fractures (p < 0.01), with HU (AUC = 0.863) showcasing the highest predictive efficacy, followed by the DEXA-measured BMD (AUC = 0.813). VBQ (AUC = 0.602) ranked lowest among the 3 indicators. The thresholds for predicting thoracolumbar fragility fractures were as follows: HU (88),VBQ (3.37), and BMD (0.81). Conclusion: All 3 of these indicators, HU, VBQ, and BMD, can predict thoracolumbar fragility fractures. Notably, lumbar vertebral HU exhibits the highest predictive efficacy, followed by the BMD obtained through DEXA scanning, with VBQ demonstrating the lowest predictive efficacy.

      • Research of Acoustic Emission Testing Method with Application to Monitored for Wind Turbines

        Qin Hongwu,Zhang Chao,Zhang Xian,Fan Qinyin 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.1

        Acoustic Emission method of nondestructive check is based on exertion wave radiation and their registration during fast local material structure reorganization. It is used as a means of analysis of materials, constructions, productions control and diagnosis during operating time. In the article, it is applied to structural health monitoring of Wind Turbines. Acoustic emission testing is based condition monitoring system uses data already collected at the wind turbine controller. It is an effective way to monitor wind turbines for early warning of failures and performance issues. We used a number of measurements to develop anomaly detection algorithms and investigated classification techniques using clustering algorithms and principal components analysis for capturing fault signatures. When registering signal amplitude it is required to consider its frequency distribution connecting each amplitude rate with the corresponding vibration rate. The correlation and signal to noise ratio were evaluated by the algorithm based on frequency spectrum. Classical method of frequency distortion influence exclusion consists of FRF calculation with subsequent adjustment of received signals spectral characteristics.

      • KCI등재

        The evaluation of online course of Traditional Chinese Medicine for Medical Bachelor, Bachelor of Surgery international students during the COVID-19 epidemic period

        Zhang Qing,He Yi-Jing,Zhu Yu-Hang,Dai Min-Chen,Pan Man-Man,Wu Jia-Qi,Zhang Xian,Gu Ying-Er,Wang Fang-Fang,Xu Xiang-Rong,Qu Fan 한국한의학연구원 2020 Integrative Medicine Research Vol.9 No.3

        Background: During the COVID-19 epidemic period, Traditional Chinese Medicine (TCM) course for international students of Medical Bachelor, Bachelor of Surgery (MBBS) program in Zhejiang University has shifted from traditional classroom to online environment. This study aimed to investigate MBBS international students’ perception on online TCM course, and to assess the online learning efficacy. Methods: A total of 84 MBBS international students attending course of “Basic Traditional Chinese Medicine” during 2020 academic years at Zhejiang University were enrolled in this study. A quantitative questionnaire was respectively completed before and after the TCM course using a pretest–post-test design. By means of two online learning platforms, Learning in ZJU and DingTalk, TCM course was broadcast in both live and archived format to students. Results: A total of 48 participants completed both baseline and follow-up questionnaires. The majority of participants preferred face-to-face classroom learning (26, 54.17% of total) when compared with online learning. Students felt that the course had brought in much benefits (mean 3.88, SD 0.87), and they were satisfied with the course content (mean 3.83, SD 0.95). Students’ TCM related knowledge and their behaviors of discussion and consulting were significantly improved by online TCM course (all P < 0.001). Students’ awareness of the necessity of TCM education and their feeling of difficulty in learning TCM were significantly strengthened (P = 0.042, 0.025, respectively). Conclusion: Online learning is a good alternative for TCM course of MBBS international students when classroom learning is suspended, whereas it cannot replace the need for onsite and face-to-face learning.

      • KCI등재

        Selaginella subvaginata (Selaginellaceae), a new spikemoss from China

        Xian-Chun Zhang,Aleksandr Petrovich Shalimov,강종수,Meng-Hua Zhang 국립생물자원관 2020 Journal of species research Vol.9 No.3

        Selaginella vaginata is a common montane species with broad distribution in China and the Himalaya region, and several species that are morphologically similar to S. vaginata are distributed in Asia. The taxonomic revision of S. vaginata and related species was performed by morphological comparison of leaves, strobili, and spores, and phylogenetic analysis. Based on these results, a new species, S. subvaginata, sp. nov., has been identified. Morphologically, S. subvaginata has intermediate form between S. vaginata and S. repanda, which differs mainly in its main stem being erect, dorsal leaves long-ciliolate on inner margin and outer margin denticulate or with 2-4 cilia at base (long-ciliolate on both inner and outer margins in S. vaginata, denticulate on both inner and outer margins in S. repanda), and acroscopic base of ventral leaves long ciliolate (sparsely long ciliolate in S. vaginata, short ciliolate to denticulate in S. repanda). Moreover, phylogenetic analysis using three chloroplast markers (rbcL, atpI, and psbA) revealed that S. subvaginata is a distinct species among the anisosporophyllous species clade in Selaginellaceae.

      • KCI등재

        THE GENERAL HERMITIAN NONNEGATIVE-DEFINITE AND POSITIVE-DEFINITE SOLUTIONS TO THE MATRIX EQUATION $GXG^*\;+\;HYH^*\;=\;C$

        Zhang, Xian 한국전산응용수학회 2004 Journal of applied mathematics & informatics Vol.14 No.1

        A matrix pair $(X_0,\;Y_0)$ is called a Hermitian nonnegative-definite(respectively, positive-definite) solution to the matrix equation $GXG^*\;+\;HYH^*\;=\;C$ with unknown X and Y if $X_{0}$ and $Y_{0}$ are Hermitian nonnegative-definite (respectively, positive-definite) and satisfy $GX_0G^*\;+\;HY_0H^*\;=\;C$. Necessary and sufficient conditions for the existence of at least a Hermitian nonnegative-definite (respectively, positive-definite) solution to the matrix equation are investigated. A representation of the general Hermitian nonnegative-definite (respectively positive-definite) solution to the equation is also obtained when it has such solutions. Two presented examples show these advantages of the proposed approach.

      • KCI등재

        Anti-obesity effect of resveratrol-amplified grape skin extracts on 3T3-L1 adipocytes differentiation

        Xian-Hua Zhang,Bo Huang,Soo-Kyong Choi,Jung-Sook Seo 한국영양학회 2012 Nutrition Research and Practice Vol.6 No.4

        Resveratrol (3,4,5-trihydroxy-trans-stilbene), a phytoalexin found in grape skin, grape products, and peanuts as well as red wine, has been reported to have various biological and pharmacological properties. The purpose of this study was to investigate the anti-obesity effect of resveratrol-amplified grape skin extracts on adipocytes. The anti-obesity effects of grape skin extracts were investigated by measuring proliferation and differentiation in 3T3-L1 cells. The effect of grape skin ethanol extracts on cell proliferation was detected by the MTS assay. The morphological changes and degree of adipogenesis of preadipocyte 3T3-L1 cells were measured by Oil Red-O staining assay. Treatment with extracts of resveratrol-amplified grape skin decreased lipid accumulation and glycerol-3-phosphate dehydrogenase activity without affecting 3T3-L1 cell viability. Grape skin extract treatment resulted in significantly attenuated expression of key adipogenic transcription factors, including peroxisome proliferator-activated receptor, CCAAT/enhancer-binding proteins, and their target genes (FAS, aP2, SCD-1, and LPL). These results indicate that resveratrol-amplified grape skin extracts may be useful for preventing obesity by regulating lipid metabolism.

      • Multiple Smooth Support Vector Machine with FCM Clustering in Hidden Space

        Xian-wei Zhang,Jinjin Liang 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.9

        A multiple smooth model is proposed by smoothing technique and piecewise technique for large scale data. Mapping the training data to the hidden space with a hidden function, the proposed model divides the original data into several subclasses by Fuzzy C Means (FCM), whose initial cluster centers are selected by samples with large density indexes; derives the smooth differentiable model by utilizing the entropy function to replace the plus function of the slack vector, and introduces linking rules to combine results of subclasses. Simulations demonstrate that the obtained algorithm maintains good classification accuracies, reduces the training time and hardly varies with kernel parameters.

      • Study of the flow around a cylinder from the subcritical to supercritical regimes

        Zhang, Xian-Tao,Li, Zhi-Yu,Fu, Shi-Xiao,Ong, Muk Chen,Chen, Ying Techno-Press 2014 Ocean systems engineering Vol.4 No.3

        The objective of the present simulations is to evaluate the applicability of the standard $k-{\varepsilon}$ turbulence model in engineering practice in the subcritical to supercritical flow regimes. Two-dimensional numerical simulations of flow around a circular cylinder at $Re=1{\times}10^5$, $5{\times}10^5$ and $1{\times}10^6$, had been performed using Unsteady Reynolds-Averaged Navier Stokes (URANS) equations with the standard $k-{\varepsilon}$ turbulence model. Solution verification had been studied by evaluating grid and time step size convergence. For each Reynolds number, several meshes with different grid and time step size resolutions were chosen to calculate the hydrodynamic quantities such as the time-averaged drag coefficient, root-mean square value of lift coefficient, Strouhal number, the coefficient of pressure on the downstream point of the cylinder, the separation angle. By comparing the values of these quantities of adjacent grid or time step size resolutions, convergence study has been performed. Solution validation is obtained by comparing the converged results with published numerical and experimental data. The deviations of the values of present simulated quantities from those corresponding experimental data become smaller as Reynolds numbers increases from $1{\times}10^5$ to $1{\times}10^6$. This may show that the standard $k-{\varepsilon}$ model with enhanced wall treatment appears to be applicable for higher Reynolds number turbulence flow.

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