Robust Finite-time Attitude Tracking Control of Rigid Spacecraft Under Actuator Saturation

Hai-Tao Chen,Shen-Min Song,Zhi-Bin Zhu 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.1

This paper investigates the robust finite-time attitude tracking control problem for rigid spacecraft considering the modeling uncertainty, external disturbance and actuator saturation. An auxiliary system is proposed to directly compensate for the saturated control input. First, the basic controller is formulated based on the fast nonsingular terminal sliding mode surface (FNTSMS), the fast-TSM-type reaching law and the auxiliary system in the presence of upper bounded external disturbance. Then, when facing system uncertainty which consists of both modeling uncertainty and external disturbance and has upper bounded first derivative, the extended state observer (ESO) is associated with the first controller to improve the robustness of control system. Furthermore, to handle more general system uncertainty which is upper bounded by a polynomial function of the closed-loop system states, a continuous adaptive controller is designed to compensate for the total system uncertainty on line. The proposed controllers are able to deal with system uncertainty, input singularity and actuator saturation, while simultaneously providing fast finite-time convergence speed for the control system. And the problems of complex parameters selection process and repeated differentiations of nonlinear functions can be avoided. Rigorous stability analyses are given via the Lyapunov stability theory and digital simulations are conducted to illustrate the effectiveness of the proposed controllers.

Characterization of proteolysis in muscle tissues of sea cucumber Stichopus japonicus

Chen-Chen Zhao,Yang Yang,Hai-tao Wu,Zhi-Mo Zhu,Yue Tang,Cui-Ping Yu,Na Sun,Qiang Lv,Jia-Run Han,Ao-Ting Li,Jia-Nan Yan,Yue Cha 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.6

The proteolysis in muscle tissues of sea cucumber Stichopus japonicus (sjMTs) was characterized. The proteins from sjMTs were primarily myosin heavy chains (MHCs), paramyosin (Pm), and actin (Ac) having a molecular mass of approximately 200, 98, and 42 kDa, respectively. Based on SDS-PAGE analysis and quantification of trichloroacetic acid (TCA)-soluble peptides released, degradation of muscle proteins from sjMTs was favorable at pH 5 and 50°C. Proteolysis of MHCs was mostly inhibited by cysteine protease inhibitors, including trans-epoxysuccinyl-L-leucyl-amido (4- guanidino) butane (E-64) and antipain (AP). E-64 and AP completely inhibited the degradation of Pm and Ac, while iodoacetic acid showed a partially inhibitory effect. These results indicated that the proteolysis of sjMTs was mainly attributed to cysteine proteases. Avoidance of setting the tissues at 40–50oC and slightly acidic condition and inhibition of cysteine proteases are helpful for decreasing sea cucumber autolysis.

Synthesis of g-C3N4/diatomite/MnO2 composites and their enhanced photo-catalytic activity driven by visible light

Chen Ran-Ran,Ren Qi-Fang,Liu Yu-Xin,Ding Yi,Zhu Hai-Tao,Xiong Chun-Yu,Jin Zhen,오원춘 한국세라믹학회 2021 한국세라믹학회지 Vol.58 No.5

Herein, a novel visible-light-responsive g-C 3 N 4 /diatomite/MnO 2 composite was successfully fabricated through a simple redox reaction method. The structure and morphology of the sample are mainly characterized by X-ray diff raction (XRD), photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), transmis- sion electron microscopy (TEM), and ultraviolet–visible spectroscopy (UV–Vis). In this paper, the photo-catalytic activity of the sample was evaluated by degradation RhB under visible-light irradiation. The results shown that, compared with g-C 3 N 4 /diatomite composite, MnO 2 , g-C 3 N 4 , diatomite, the prepared g-C 3 N 4 /diatomite/2.5%MnO 2 composite exhibits bet- ter photo-catalytic activity and stability. At the same time, the eff ect of diff erent MnO 2 additions on the photo-catalytic activity of the composite material was further analyzed. The results indicated that the g-C 3 N 4 /MnO 2 /diatomite composites exhibit highest photo-catalytic activity when the adding amount of MnO 2 reached 2.5%. The degradation rate of the g-C 3 N 4 / diatomite/2.5%MnO 2 is 93% after recycling for three times, showing good stability and reusability. Moreover, the mechanism of catalytic performance enhancement also has been discussed.

Establishment of Paclitaxel-resistant Breast Cancer Cell Line and Nude Mice Models, and Underlying Multidrug Resistance Mechanisms in Vitro and in Vivo

Chen, Si-Ying,Hu, Sa-Sa,Dong, Qian,Cai, Jiang-Xia,Zhang, Wei-Peng,Sun, Jin-Yao,Wang, Tao-Tao,Xie, Jiao,He, Hai-Rong,Xing, Jian-Feng,Lu, Jun,Dong, Ya-Lin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Background: Breast cancer is a common malignant tumor which affects health of women and multidrug resistance (MDR) is one of the main factors leading to failure of chemotherapy. This study was conducted to establish paclitaxel-resistant breast cancer cell line and nude mice models to explore underlying mechanisms of MDR. Methods: The breast cancer drug-sensitive cell line MCF-7 (MCF-7/S) was exposed in stepwise escalating paclitaxel (TAX) to induce a resistant cell line MCF-7/TAX. Cell sensitivity to drugs and growth curves were measured by MTT assay. Changes of cell morphology and ultrastructure were examined by optical and electron microscopy. The cell cycle distribution was determined by flow cytometry. Furthermore, expression of proteins related to breast cancer occurrence and MDR was tested by immunocytochemistry. In Vivo, nude mice were injected with MCF-7/S and MCF-7/TAX cells and weights and tumor sizes were observed after paclitaxel treatment. In addition, proteins involved breast cancer and MDR were detected by immunohistochemistry. Results: Compared to MCF-7/S, MCF-7/TAX cells had a higher resistance to paclitaxel, cross-resistance and prolonged doubling time. Moreover, MCF-7/TAX showed obvious alterations of ultrastructure. Estrogen receptor (ER) expression was low in drug resistant cells and tumors while expression of human epidermal growth factor receptor 2 (HER2) and Ki-67 was up-regulated. P-glycoprotein (P-gp), lung resistance-related protein (LRP) and glutathione-S-transferase-${\pi}$ (GST-${\pi}$) involved in the MDR phenotype of resistant cells and tumors were all overexpressed. Conclusion: The underlying MDR mechanism of breast cancer may involve increased expression of P-gp, LRP and GST-${\pi}$.

β-elemene Induces Caspase-dependent Apoptosis in Human Glioma Cells in vitro through the Upregulation of Bax and Fas/FasL and Downregulation of Bcl-2

Li, Chen-Long,Chang, Liang,Guo, Lin,Zhao, Dan,Liu, Hui-Bin,Wang, Qiu-Shi,Zhang, Ping,Du, Wen-Zhong,Liu, Xing,Zhang, Hai-Tao,Liu, Yang,Zhang, Yao,Xie, Jing-Hong,Ming, Jian-Guang,Cui, Yu-Qiong,Sun, Ying Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Background: ${\beta}$-elemene, extracted from herb medicine Curcuma wenyujin has potent anti-tumor effects in various cancer cell lines. However, the activity of ${\beta}$-elemene against glioma cells remains unclear. In the present study, we assessed effects of ${\beta}$-elemene on human glioma cells and explored the underlying mechanism. Materials and Methods: Human glioma U87 cells were used. Cell proliferation was determined with MTT assay and colony formation assay to detect the effect of ${\beta}$-elemene at different doses and times. Fluorescence microscopy was used to observe cell apoptosis with Hoechst 33258 staining and change of glioma apoptosis and cell cycling were analyzed by flow cytometry. Real-time quantitative PCR and Western-blotting assay were performed to investigated the influence of ${\beta}$-elemene on expression levels of Fas/FasL, caspase-3, Bcl-2 and Bax. The experiment was divided into two groups: the blank control group and ${\beta}$-elemne treatment group. Results: With increase in the concentration of ${\beta}$-elemene, cytotoxic effects were enhanced in the glioma cell line and the concentration of inhibited cell viability ($IC_{50}$) was $48.5{\mu}g/mL$ for 24h. ${\beta}$-elemene could induce cell cycle arrest in the G0/G1 phase. With Hoechst 33258 staining, apoptotic nuclear morphological changes were observed. Activation of caspase-3,-8 and -9 was increased and the pro-apoptotic factors Fas/FasL and Bax were upregulated, while the anti-apoptotic Bcl-2 was downregulated after treatment with ${\beta}$-elemene at both mRNA and protein levels. Furthermore, proliferation and colony formation by U87 cells were inhibited by ${\beta}$-elemene in a time and does-dependent manner. Conclusions: Our results indicate that ${\beta}$-elemene inhibits growth and induces apoptosis of human glioma cells in vitro. The induction of apoptosis appears to be related with the upregulation of Fas/FasL and Bax, activation of caspase-3,-8 and -9 and downregulation of Bcl-2, which then trigger major apoptotic cascades.

Gingerol Inhibits Cisplatin-induced Vomiting by Down Regulating 5-Hydroxytryptamine, Dopamine and Substance P Expression in Minks

Qiu-hai Qian,Wen-hui Chen,Wang Yue,Yao-xia Wang,Zhi-hong Yang,Zhan-tao Liu 대한약학회 2009 Archives of Pharmacal Research Vol.32 No.4

Objective: To investigate the antiemetic effect of gingerol and its multi-targets effective mechanism on 5-hydroxytryptamine (5-HT), dopamine (DA) and substance P (SP). The antiemetic effect of gingerol was investigated on a vomiting model of mink induced by cisplatin (7.5 mg· kg−1, i.p.) in 6 h observation. The levels of 5-HT, DA and distribution of substance P in the area postrema and ileum were measured by high performance liquid chromatography (HPLC) and immunohistochemistry respectively. The frequency of cisplatin induced retching and vomiting was significantly reduced by pretreatment with gingerol in a dose-dependent manner (P<0.05). Cisplatin produced a significant increase in 5-HT and DA levels in the area postrema and ileum of minks (P<0.05), and this increase was significantly inhibited by gingerol in a dose-dependent manner (P<0.05). Substance P-immunoreactive was mainly situated in the mucosa and submucosa of ileum as well as in the neurons of area postrema, and gingerol markedly suppressed the increase immunoreactivity of substance P induced by cisplatin in a dose-dependent manner (P<0.05). Gingerol has good activity against cisplatin-induced emesis in minks possibly by inhibiting central or peripheral increase of 5-HT, DA and substance P.

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.

In Vivo Evaluation of Curcumin-loaded Nanoparticles in a A549 Xenograft Mice Model

Yin, Hai-Tao,Zhang, De-Geng,Wu, Xiao-Li,Huang, Xin-En,Chen, Gang Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Curcumin (Cum) has been reported to have potential chemo-preventive and chemotherapeutic activity through influencing various processes, inducing cell cycle arrest, differentiation and apoptosis in a series of cancers. However, the poor solubility of Cum limits its further applications in the treatment of cancer. We have previously reported Cum-loaded nanoparticles (Cum-NPs) prepared with amphilic methoxy poly(ethylene glycol)-polycaprolactone (mPEG-PCL) block copolymers. The current study demonstrated superior antitumor efficacy of Cum-NPs over free Cum in the treatment of lung cancer. In vivo evaluation further demonstrated superior anticancer effects of Cum-NPs by delaying tumor growth compared to free Cum in an established A549 transplanted mice model. Moreover, Cum-NPs showed little toxicity to normal tissues including bone marrow, liver and kidney at a therapeutic dose. These results suggest that Cum-NPs are effective to inhibit the growth of human lung cancer with little toxicity to normal tissues, and could provide a clinically useful therapeutic regimen. They thus merit more research to evaluate the feasibility of clinical application.

Enhancing mucosal immunity in mice by recombinant adenovirus expressing major epitopes of porcine circovirus-2 capsid protein delivered with cytosine-phosphate-guanosine oligodeoxynucleotides

Hong-tao Chang,Xiu-yuan He,Yu-Feng Liu,Lu Chen,Quan-hai Guo,Qiu-ying Yu,Jun Zhao,Xin-wei Wang,Xia Yang,Chuan-qing Wang 대한수의학회 2014 Journal of Veterinary Science Vol.15 No.3

A recombinant replication-defective adenovirus expressingthe major epitopes of porcine circovirus-2 (PCV-2) capsidprotein (rAd/Cap/518) was previously constructed and shownto induce mucosal immunity in mice following intranasaldelivery. In the present study, immune responses induced byintranasal immunization with a combination of rAd/Cap/518and cytosine-phosphate-guanosine oligodeoxynucleotides(CpG ODN) were evaluated in mice. The levels ofPCV-2-specific IgG in serum and IgA in saliva, lung, andintestinal fluids were significantly higher in the groupimmunized with rAd/Cap/518 and CpG ODN than animalsimmunized with rAd/Cap/518 alone. The frequencies ofIL-2-secreting CD4+ T cells and IFN-γ-producing CD8+ T cellswere significantly higher in the combined immunizationgroup than mice immunized with rAd/Cap/518 alone. Thefrequencies of CD3+, CD3+CD4+CD8−, and CD3+CD4−CD8+T cells in the combined immunization group were similar tothat treated with CpG ODN alone, but significantly higherthan mice that did not receive CpG ODN. PCV-2 load afterchallenge in the combined immunization group wassignificantly lower than that in the phosphate-buffered salineplacebo group and approximately 7-fold lower in the grouptreated with CpG ODN alone. These results indicate thatrAd/Cap/518 combined with CpG ODN can enhance systemicand local mucosal immunity in mice, and represent apromising synergetic mucosal vaccine against PCV-2.

Temporal coherent image segmentation and its applications

Song-Hai Zhang,Xian-Ying Li,Tao Chen,Yi-Fei Zhang,Shi-Min Hu,Ralph Martin (사)한국CDE학회 2010 한국CAD/CAM학회 국제학술발표 논문집 Vol.2010 No.8

We propose a trapped-ball method for image segmentation, which is fast, supports non-uniformly colored regions, and allows robust region segmentation even in the presence of imperfectly linked region edges. We also introduce two applications by using the trapped-ball image segmentation, for temporal coherent animations generation and editing. First, we present a system for vectorizing 2D raster format cartoon animations by the segmentation method and background construction. The output animations are visually flicker free, smaller in file size, and easy to edit. And then we present an automatic method for online video stream stylization, producing a temporally coherent output video stream, based on the trapped-ball segmentation and optical flow. Our system transforms video into an abstract style with large regions of constant color and highlighted bold edges.