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      • KCI등재후보
      • KCI등재

        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.

      • KCI등재

        A Signal Characteristic Based Cluster Scheme for Aeronautical Ad Hoc Networks

        ( Yu Tian ),( Linhua Ma ),( Le Ru ),( Hong Tang ),( Bo Song ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.10

        Clustering is an effective method for improving the performance of large scale mobile ad hoc networks. However, when the moving speed is very fast, the topology changes quickly, which leads to frequent cluster topology updates. The drastically increasing control overheads severely threaten the throughput of the network. SCBCS (Signal Characteristic Based Cluster Scheme) is proposed as a method to potentially reduce the control overheads caused by cluster formation and maintenance in aeronautical ad hoc networks. Each node periodically broadcasts Hello packets. The Hello packets can be replaced by data packets, which preserve bandwidth. The characteristics of the received packets, such as the Doppler shift and the power of two successive Hello packets, help to calculate the relative speed and direction of motion. Then, the link connection lifetime is estimated by the relative speed and direction of motion. In the clustering formation procedure, the node with the longest estimated link connection time to its one-hop neighbors is chosen as the cluster head. In the cluster maintenance procedure, re-affiliation and re-clustering schemes are designed to keep the clusters more stable. The re-clustering phenomenon is reduced by limiting the ripple effect. Simulations have shown that SCBCS prolongs the link connection lifetime and the cluster lifetime, which can reduce the topology update overheads in highly dynamic aeronautical ad hoc networks.

      • KCI등재

        Transcriptional activation of insulin-like growth factor binding protein 6 by 17β-estradiol in SaOS-2 cells

        Yu-yan Zhao,Lei Guo,Xiao-juan Zhao,Hong Liu,Tian Lei,Dong-jie Ma,Xiao-yu Gao 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.7

        Osteoblasts can synthesize the insulin-like growth factors (IGFs) and the IGF-binding proteins (IGFBPs), which may either enhance or attenuate IGF-stimulated bone cell proliferation. Since estrogen induced osteoblastic differentiation and proliferation through an estrogen- responsive gene in target cells, we investigated the effects of estrogen on IGFBP-6 expression in the human osteoblastic-like cell line SaOS-2. Expressions of IGFBP-6 protein and mRNA increased 2.8 and 2-fold, respectively, in the presence of 17-β-estradiol (E2) (0.01 to 1 μM) and estrogen receptor (ER) in SaOS-2 cells. On the other hand, E2 induced a 2-fold increase in SaOS-2 cell proliferation. To identify genomic sequences associated with estrogen responsiveness, the 5'-promoter region (-44 to +118) of the IGFBP-6 gene was cloned into a chloramphenicol acetyltransferase (CAT) reporter vector. E2 induced a 3-fold increase in CAT activity in SaOS-2 cells transiently transfected with this construct. Identification of the estrogen- responsive element (ERE) [5'-CCTTCA CCTG-3'] (-9 to +1) in this IGFBP-6 gene promoter region was confirmed using electromobility shift assays and deletion analysis. This functional ERE was important for E2-induced trans-activation of the IGFBP-6 gene. These results demonstrate that E2 exhibits a positive effect on IGFBP-6 gene transcription through estrogen- liganded ER binding to the functional ERE in the IGFBP-6 gene promoter in SaOS-2 cells. Osteoblasts can synthesize the insulin-like growth factors (IGFs) and the IGF-binding proteins (IGFBPs), which may either enhance or attenuate IGF-stimulated bone cell proliferation. Since estrogen induced osteoblastic differentiation and proliferation through an estrogen- responsive gene in target cells, we investigated the effects of estrogen on IGFBP-6 expression in the human osteoblastic-like cell line SaOS-2. Expressions of IGFBP-6 protein and mRNA increased 2.8 and 2-fold, respectively, in the presence of 17-β-estradiol (E2) (0.01 to 1 μM) and estrogen receptor (ER) in SaOS-2 cells. On the other hand, E2 induced a 2-fold increase in SaOS-2 cell proliferation. To identify genomic sequences associated with estrogen responsiveness, the 5'-promoter region (-44 to +118) of the IGFBP-6 gene was cloned into a chloramphenicol acetyltransferase (CAT) reporter vector. E2 induced a 3-fold increase in CAT activity in SaOS-2 cells transiently transfected with this construct. Identification of the estrogen- responsive element (ERE) [5'-CCTTCA CCTG-3'] (-9 to +1) in this IGFBP-6 gene promoter region was confirmed using electromobility shift assays and deletion analysis. This functional ERE was important for E2-induced trans-activation of the IGFBP-6 gene. These results demonstrate that E2 exhibits a positive effect on IGFBP-6 gene transcription through estrogen- liganded ER binding to the functional ERE in the IGFBP-6 gene promoter in SaOS-2 cells.

      • KCI등재

        Non-Benzoquinone Geldanamycin Analog, WK-88-1, Induces Apoptosis in Human Breast Cancer Cell Lines

        ( Yu-ru Zhao ),( Hong-mei Li ),( Meilin Zhu ),( Jing Li ),( Tao Ma ),( Qiang Huo ),( Young-soo Hong ),( Cheng-zhu Wu ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.4

        Heat shock protein 90 (Hsp90) is treated as a molecular therapeutic target for the prevention and treatment of cancer. Geldanamycin (GA) was the first identified natural Hsp90 inhibitor, but hepatotoxicity has limited its clinical application. Nevertheless, a new GA analog (WK-88- 1) with the non-benzoquinone skeleton, obtained from genetically engineered Streptomyces hygroscopicus, was found to have anticancer activity against two human breast cancer cell lines. WK-88-1 produced concentration-dependent inhibition of cell proliferation, cell cycle arrest, and apoptosis in estrogen receptor (ER)-positive MCF-7 and ER-negative MDA-MB-231 cell lines. Detailed analysis showed that WK-88-1 downregulated some key cell cycle molecules (CDK1 and cyclin B1) and lead to G2/M cell cycle arrest. Further studies also showed that WK- 88-1 could induce human breast cancer cell apoptosis by downregulating Hsp90 client proteins (Akt, p-Akt, IKK, c-Raf, and Bcl-2), decreasing the ATP level, increasing reactive oxygen species production, and lowering the mitochondrial membrane potential. Meanwhile, we discovered that WK-88-1 significantly decreased the levels of Her-2 and ER-α in MCF-7 cells but not in MDA-MB-231 cells. In addition, WK-88-1 significantly increased caspase-3, -8, and -9 activities and the cleavage of PARP in a concentration-dependent manner (with the exception of caspase-3 and PARP in MCF-7 cells). Taken together, our preliminary results suggest that WK-88-1 has the potential to play a role in breast cancer therapy.

      • SCIESCOPUSKCI등재
      • Association Between MDM2 Promoter SNP309 T/G Polymorphism and Liver Cancer Risk - a Meta-analysis

        Ma, Hong-Bo,Huang, Tao,Han, Feng,Chen, Wei-Yu Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.6

        Background: Many studies have investigated the association between the MDM2 promoter SNP309 T/G polymorphism and liver cancer risk, but inconsistencies make drawwing definitive conclusions difficult. Methods: We therefore searched main databases for articles relating MDM2 SNP309 T/G polymorphism to risk of liver cancer in humans and estimated summary odds ratio (OR) with 95% confidence intervals (95% CI) to assess the possible association in a meta-analysis. Results: The main analysis revealed no significant heterogeneity, and the pooled ORs of fixed-effects were all significant (for G versus T, OR = 1.59, 95% CI 1.42-1.78; for GG versus TT, OR = 2.45, 95% CI 1.93-3.12; for GT versus TT, OR = 1.70, 95% CI 1.38-2.09; for GG versus GT, OR = 1.49, 95% CI 1.24-1.79; for GG and GT versus TT, OR = 1.95, 95% CI 1.61-2.38; for GG versus TT and GT, OR = 1.73, 95% CI 1.46-2.07). Subgroup analyses by ethnicity and sensitivity analyses both showed associations to remain significant. Conclusion: The present meta-analysis of available data showed a significant association between the MDM2 SNP309 T/G polymorphism and liver cancer risk, the MDM2 SNP309 G allele contributing to increased risk in both Asians and Caucasians in a graded, dose-dependent fashion.

      • KCI등재

        Radiological gastrostomy: A comparative analysis of different image-guided methods

        Hong-Tao Hu,Hang Yuan,Chen-Yang Guo,Quan-Jun Yao,Xiang Geng,Hong-Tao Cheng,Jun-Li Ma,Yan Zhao,Li Jiang,Yu-Qing Zhao,Hai-Liang Li 소화기인터벤션의학회 2021 International journal of gastrointestinal interven Vol.10 No.2

        Background: Radiographic guided percutaneous gastrostomy has become a safe and effective enteral nutrition method for patients who can not eat by mouth. Fluoroscopy, computed tomography (CT) and cone-beam CT have been routinely used clinically. The aim of this study was to compare the advantages and disadvantages of percutaneous gastrostomy using different radiographic guided methods. Methods: We retrospectively analyzed the clinical data of 538 patients undergoing percutaneous gastrostomy in our department. According to the image guidance method used in gastrostomy, the patients were divided into groups A by fluoroscopy guidance, group B by fluoroscopy combined with C-arm CT guidance, and group C with the whole process CT guidance. The gastrostomy success rate, complication rate, procedure time, and patient radiation dose were analyzed in the three groups. Results: Among 538 patients, 534 were successful and the success rates are 94.3%, 99.3%, and 100% in group A, B, and C, respectively (P > 0.05). There were 3 cases occurred postoperative bleeding as serious adverse events and transferred to surgical gastrostomy. The minor complications include local infection, hyperplasia of granulation tissue, tube obstruction or prolapse, and local pain of the ostomy. The minor complication rates were 10.5%, 10.4%, and 7.7% in group A, B, and C, respectively (P > 0.05). The average procedure time was 25.57 ± 5.99 minutes, 29.01 ± 6.63 minutes, and 45.47 ± 8.98 minutes, respectively (χ2 = 87.98, P < 0.001). The average radiation dosage was 27.30 ± 19.27 mGy, 145.07 ± 106.08 mGy, and 2,590.26 ± 1,088.22 mGy, respectively (χ2 = 204.44, P < 0.001). Conclusion: There were no significant differences in the success rates and complication rates of gastrostomy under the three guiding methods. For difficult cases, CT-guided gastrostomy may be a very useful supplemental method.

      • KCI등재

        Optimization of Nobiletin Extraction Assisted by Microwave from Orange Byproduct Using Response Surface Methodology

        Yu Zhang,Hong-Jun Li,Huating Dou,Zhi-Fei He,Houjiu Wu,Zhigao Sun,Hua Wang,Xuegen Huang,Yaqin Ma 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.suppl1

        Nobiletin (NOB) is a well-known polymethoxylated flavone that has only been found in citrus. The objective of this study is to obtain the optimal conditions for extracting nobiletin from sweet orange residues by microwave-assisted extraction (MAE) using response surface method. By using the Box-Behnken experimental design and SAS software 3 independent variables including solid/solvent ratio, microwave power, and treatment time were examined for the response variable nobiletin extraction yield. The regression Eq. 7 statistically significant (p<0.001) and R2 was 0.9189. Based on our regression result and considering the feasibility of experiment conduction, we chose the following independent variable values as the optimized conditions for the extraction of NOB: 1:21.91(g/mL) for the solid/solvent ratio, 14.16 min for the treatment time, and 693.72 W for the microwave power. Under these conditions, the nobiletin yield of 267.8 μg/g of byproduct was achieved.

      • KCI등재

        Radiological gastrostomy: A comparative analysis of different image-guided methods

        Hong-Tao Hu,Hang Yuan,Chen-Yang Guo,Quan-Jun Yao,Xiang Geng,Hong-Tao Cheng,Jun-Li Ma,Yan Zhao,Li Jiang,Yu-Qing Zhao,Hai-Liang Li 소화기인터벤션의학회 2021 Gastrointestinal Intervention Vol.10 No.2

        Background: Radiographic guided percutaneous gastrostomy has become a safe and effective enteral nutrition method for patients who can not eat by mouth. Fluoroscopy, computed tomography (CT) and cone-beam CT have been routinely used clinically. The aim of this study was to compare the advantages and disadvantages of percutaneous gastrostomy using different radiographic guided methods. Methods: We retrospectively analyzed the clinical data of 538 patients undergoing percutaneous gastrostomy in our department. According to the image guidance method used in gastrostomy, the patients were divided into groups A by fluoroscopy guidance, group B by fluoroscopy combined with C-arm CT guidance, and group C with the whole process CT guidance. The gastrostomy success rate, complication rate, procedure time, and patient radiation dose were analyzed in the three groups. Results: Among 538 patients, 534 were successful and the success rates are 94.3%, 99.3%, and 100% in group A, B, and C, respectively (P > 0.05). There were 3 cases occurred postoperative bleeding as serious adverse events and transferred to surgical gastrostomy. The minor complications include local infection, hyperplasia of granulation tissue, tube obstruction or prolapse, and local pain of the ostomy. The minor complication rates were 10.5%, 10.4%, and 7.7% in group A, B, and C, respectively (P > 0.05). The average procedure time was 25.57 ± 5.99 minutes, 29.01 ± 6.63 minutes, and 45.47 ± 8.98 minutes, respectively (χ2 = 87.98, P < 0.001). The average radiation dosage was 27.30 ± 19.27 mGy, 145.07 ± 106.08 mGy, and 2,590.26 ± 1,088.22 mGy, respectively (χ2 = 204.44, P < 0.001). Conclusion: There were no significant differences in the success rates and complication rates of gastrostomy under the three guiding methods. For difficult cases, CT-guided gastrostomy may be a very useful supplemental method.

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