Control-Oriented Modeling of a Three-Dimensional Hypersonic Vehicle with Rigid/Flexible Coupling

Xi-bin Zhang,Yu-mei Ding,Zhen-xing Zhang 한국항공우주학회 2022 International Journal of Aeronautical and Space Sc Vol.23 No.2

Modeling for a hypersonic vehicle is a great challenging task due to its tightly integrated airframe/propulsion system and flexible structure. A three-dimensional, six-degree-of-freedom, physics-based hypersonic vehicle model is being established that can capture the real physical characteristics for control studies. Flexible effects, aerodynamic loads and viscous effects are calculated using or combining variation method, shock/expansion theory and Eckert’s reference temperature method. Based on curve fit approximation of the forces and moments of the vehicle, a control-oriented six-degree-of-freedom model is then developed. The simulations illustrate that the surrogate model contain aerodynamic/structure/propulsion interactions of the vehicle, and can support designing of the model-based control.

Abnormalities in Inflammatory Cytokines Confer Susceptible to Chronic Neuropathic Pain-related Anhedonia in a Rat Model of Spared Nerve Injury

Xi Fang,Gaofeng Zhan,Jie Zhang,Hui Xu,Bin Zhu,Yimin Hu,Chun Yang,Ailin Luo 대한정신약물학회 2019 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.17 No.2

Objective: Patients with chronic neuropathic pain (CNP) have a higher incidence to develop depression. However, its pathogenesis has not yet been fully elucidated. Here we aimed to investigate the role of inflammatory cytokines in CNP-related anhedonia, which is a core symptom of depression, and to explore the effects of ketamine and parecoxib on pain and anhedonia. Methods: A rat model of spared nerve injury (SNI) was constructed to mimic CNP. Hierarchical cluster analysis of sucrose preference test (SPT) was applied to classify the SNI rats into anhedonia susceptible and unsusceptible. Inflammatory cytokines in medial prefrontal cortex (mPFC) of brain, serum and L2-5 spinal cord were measured. Moreover, effects of ketamine or parecoxib on mechanical withdrawal test (MWT) and SPT in anhedonia susceptible rats were detected. Results: Tumor necrosis factor (TNF)- was increased in mPFC, serum and and spinal cord of anhedonia susceptible rats. Furthermore, anhedonia susceptible and unsusceptible rats both increased the interleukin (IL)-1 level in mPFC, serum and spinal cord. IL-6 was altered in serum and spinal cord, but not in mPFC. IL-10 was significantly altered in mPFC and serum, but not in spinal cord. Additionally, ketamine treatment significantly attenuated the decreased results of MWT and SPT in anhedonia susceptible rats, and that parecoxib significantly improved the MWT score, but failed to alter the result of SPT. Conclusion: These findings suggest that abnormalities in inflammatory cytokines confer susceptible to anhedonia in a rat model of SNI. Ketamine, a fast-acting antidepressant, has pharmacological benefits to alleviate pain and anhedonia symptoms.

Comparative study of tip leakage vortex trajectory and cavitation in an axial flow pump with various tip clearances

Xi Shen,Desheng Zhang,Bin Xu,Haoran Wu,Peng Wang,Weidong Shi 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.3

In order to analyze the effect of blade tip-gap size on the tip leakage vortex (TLV) dynamics and TLV-induced cavitation, a scaled axial flow pump model was created and numerically studied by the combination of an improved SST k-ω turbulence model and a homogeneous cavitation model. The trajectories of TLV core was obtained by using the swirling strength method at different tip-gap sizes vary significantly. The scale of TLV increases as the tip-gap size increases, and the starting point of TLV is sliding further downstream along the blade chord. The angle between the blade suction surface and the TLV also presented an increasing trend with the tip-gap size. The statistics of the velocity normal to the tip chord, as well as the turbulent kinetic energy (KTE) distributions were employed to illustrate a more disordered flow field, which was generated in the tip clearance in a larger amount of leaking flow due to the increased tip-gap size. The in-plain static pressure and vapor volume fraction distributions at different blade chord sections, coupled with three-dimensional cavitation patterns among three tip gaps, are further analyzed to verify the wandering motion of TLV, which shows good agreement with the visualization experiment. Considering the adverse effect of the TLV cavitation, a small tip gap is recommended for improving the axial flow pump performance.

Prevalence of Human Papillomavirus 16 in Esophageal Cancer Among the Chinese Population: a Systematic Review and Meta-analysis

Zhang, Shao-Kai,Guo, Lan-Wei,Chen, Qiong,Zhang, Meng,Liu, Shu-Zheng,Quan, Pei-Liang,Lu, Jian-Bang,Sun, Xi-Bin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Background and Aim: No firm evidence of HPV infection in esophageal cancer has been established to date. The aim of this meta-analysis was to investigate the prevalence of HPV 16 in esophageal cancer in China, which had a high burden of the disease. Materials and Methods: Studies on HPV infection and esophageal cancer were identified and a random-effects model was used to pool the summary prevalence and corresponding 95% confidence intervals (CIs). Results: A total of 3,429 esophageal cancer cases were evaluated from 26 eligible studies in this meta-analysis. The summary estimate for HPV16 prevalence was 0.381 (95% CI: 0.283, 0.479). The prevalence varied by geographical areas of the study, publication year, HPV detection method and types of specimen. In sensitivity analysis, HPV 16 prevalence ranged from 0.368 (95% CI: 0.276, 0.460) to 0.397 (95% CI: 0.286, 0.508). Conclusions: The results indicate a relatively high level of HPV 16 prevalence in esophageal cancer among Chinese population, although there was variation between different variables. Further studies are needed to elucidate the role of HPV in esophageal carcinogenesis with careful consideration of study design and laboratory detection method, providing more accurate assessment of the HPV status in esophageal cancer.

A Small Bipedal Trans-Scale Precision Positioning Stage Based on Inertial Stick-Slip Driving

Xi Zhang,Bowen Zhong,Bin Liu,Ziqi Jin,Zhenhua Wang,Lining Sun 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.3

The small size and high flexibility of the mobile platform is widely used in many fields such as electron scanning microscope (SEM), but the mobile platform still adopts the structure of guide rail at present and has the problem of large volume and poor flexibility, which cannot meet the requirements of SEM for small cavity. Therefore, this paper proposes a small bipedal trans-scale precision positioning stage based on the inertial stick-slip driving to achieve small size and high flexibility. The mobile platform consists of two piezoelectric actuators, a frame structure, two bottom plates, two pre-tightening screws, and magnets, and the volume is 15 mm × 10 mm × 9.5 mm. To investigate the locomotion characteristics of the mobile platform, a prototype is manufactured, and a series of experiments are carried out. The experimental results show that its linear motion velocity can reach 3.553 mm/s and its angular velocity can reach 462.72mrad/s, which means that the mobile platform has good motion performance.

Accurate Measurement of Agatston Score Using kVp-Independent Reconstruction Algorithm for Ultra-High-Pitch Sn150 kVp CT

Hu Xi,Tao Xinwei,Zhang Yueqiao,Niu Zhongfeng,Zhang Yong,Allmendinger Thomas,Kuang Yu,Chen Bin 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.11

Objective: To investigate the accuracy of the Agatston score obtained with the ultra-high-pitch (UHP) acquisition mode using tin-filter spectral shaping (Sn150 kVp) and a kVp-independent reconstruction algorithm to reduce the radiation dose. Materials and Methods: This prospective study included 114 patients (mean ± standard deviation, 60.3 ± 9.8 years; 74 male) who underwent a standard 120 kVp scan and an additional UHP Sn150 kVp scan for coronary artery calcification scoring (CACS). These two datasets were reconstructed using a standard reconstruction algorithm (120 kVp + Qr36d, protocol A; Sn150 kVp + Qr36d, protocol B). In addition, the Sn150 kVp dataset was reconstructed using a kVp-independent reconstruction algorithm (Sn150 kVp + Sa36d, protocol C). The Agatston scores for protocols A and B, as well as protocols A and C, were compared. The agreement between the scores was assessed using the intraclass correlation coefficient (ICC) and the Bland–Altman plot. The radiation doses for the 120 kVp and UHP Sn150 kVp acquisition modes were also compared. Results: No significant difference was observed in the Agatston score for protocols A (median, 63.05; interquartile range [IQR], 0–232.28) and C (median, 60.25; IQR, 0–195.20) (p = 0.060). The mean difference in the Agatston score for protocols A and C was relatively small (-7.82) and with the limits of agreement from -65.20 to 49.56 (ICC = 0.997). The Agatston score for protocol B (median, 34.85; IQR, 0–120.73) was significantly underestimated compared with that for protocol A (p < 0.001). The UHP Sn150 kVp mode facilitated an effective radiation dose reduction by approximately 30% (0.58 vs. 0.82 mSv, p < 0.001) from that associated with the standard 120 kVp mode. Conclusion: The Agatston scores for CACS with the UHP Sn150 kVp mode with a kVp-independent reconstruction algorithm and the standard 120 kVp demonstrated excellent agreement with a small mean difference and narrow agreement limits. The UHP Sn150 kVp mode allowed a significant reduction in the radiation dose.

Effects of the Hippo Signaling Pathway in Human Gastric Cancer

Zhou, Guang-Xi,Li, Xiao-Yu,Zhang, Qi,Zhao, Kun,Zhang, Cui-Ping,Xue, Chang-Hu,Yang, Kun,Tian, Zi-Bin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

Background/Aim: The Hippo signaling pathway is a newly discovered and conserved signaling cascade, which regulates organ size control by governing cell proliferation and apoptosis. This study aimed to investigate its effects in human gastric cancer. Methods: Tumor tissues (n=60), adjacent non-tumor tissues (n=60) and normal tissues (n=60) were obtained from the same patients with primary gastric cancer (GC). In addition, 70 samples of chronic atrophic gastritis (CAG) tissues were obtained from patients with intestinal metaplasia (IM) by endoscopic biopsy. Hippo signaling molecules, including Mst1, Lats1, YAP1, TAZ, TEAD1, Oct4 and CDX2, were determined by quantitative polymerase chain reaction (qPCR). Protein expression of Mst1, Lats1, YAP1, TEAD1 and CDX2 was assessed by immunohistochemistry and Western blotting. Results: Mst1, Lats1 and Oct4 mRNA expression showed an increasing tendency from GC tissues to normal gastric tissues, while the mRNA expression of YAP1, TAZ and TEAD1 was up-regulated (all P<0.01). Mst1 and Lats1 protein expression presented a similar trend with their mRNA expression. In addition, YAP1 and TEAD1 protein expression in GC was significantly higher than in the other groups (all P<0.01). CDX2 mRNA and protein expression in the CAG group were higher than in the other groups (all P<0.01). In GC, mRNA expression of Mst1, Lats1, Oct4, YAP1, TAZ, TEAD1 and CDX2 had a close correlation with lymphatic metastasis and tumor TNM stage (all P<0.01). Furthermore, protein expression of Mst1, Lats1, YAP1, TAZ, TEAD1 and CDX2 had a close correlation between each other (P<0.05). Conclusion: The Hippo signaling pathway is involved in the development, progression and metastasis of human gastric cancer. Therefore, manipulation of Hippo signaling molecules may be a potential therapeutic strategy for gastric cancer.

Prognostic Impact of Cyclin D1, Cyclin E and P53 on Gastroenteropancreatic Neuroendocrine Tumours

Liu, Shu-Zheng,Zhang, Fang,Chang, Yu-Xi,Ma, Jie,Li, Xu,Li, Xiao-Hong,Fan, Jin-Hu,Duan, Guang-Cai,Sun, Xi-Bin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Conventional classifications of gastroenteropancreatic neuroendocrine tumours (GEP-NETs) are rather unsatisfactory because of the variation in survival within each subgroup. Molecular markers are being found able to predict patient outcome in more and more tumours. The aim of this study was to characterize the expression of the proteins cyclin D1, cyclin E and P53 in GEP-NETs and assess any prognostic impact. Tumor specimens from 68 patients with a complete follow-up were studied immunohistochemically for cyclin D1, cyclin E and P53 expression. High cyclin D1 and cyclin E immunostaining (${\geq}$ 5% positive nuclei) was found in 48 (71%) and 24 (35%) cases, and high P53 staining (${\geq}$ 10% positive nuclei) in 33 (49%). High expression of P53 was more common in gastric neuroendocrine tumors and related to malignant behavior, being associate with a worse prognosis on univariate analysis (RR=1.9, 95%CI=1.1-3.2). High expression of cyclin E was significantly associated with shorter survival in the univariate analysis (RR=2.0, 95%CI=1.2-3.6) and multivariate analysis (RR=2.1, 95%CI=1.1-4.0). We found no significant correlation between the expression of cyclin D1 and any clinicopathological variables. Our study indicated a prognostic relevance for cyclin E and P53 immunoreactivity. Cyclin E may be an independent prognostic factor from the 2010 WHO Classification which should be evaluated in further studies.

Prevalence and Molecular Characterization of Echinococcus granulosus sensu stricto in Northern Xinjiang, China

Baoping Guo,Zhuangzhi Zhang,Xueting Zheng,Yongzhong Guo,Li Zhao,Ren Cai,Bingjie Wang,Mei Yang,Xi Shou,Wenbao Zhang,Bin Jia 대한기생충학ㆍ열대의학회 2019 The Korean Journal of Parasitology Vol.57 No.2

Echinococcus granulosus is an important zoonotic parasite globally causing cystic echinococcosis (CE) in hu- mans and animals. In this study, prevalence of CE and variation of cox1 gene sequence were analyzed with isolates E. granulosus collected from different areas in northern Xinjiang, China. The survey showed that 3.5% of sheep and 4.1% of cattle were infected with CE. Fragment of cox1 was amplified from all the positive sheep and cattle samples by PCR. In addition, 26 positive samples across the 4 areas were included. The isolates were all E. granulosus sensu stricto (s.s.) containing 15 haplotypes (Hap1-15), and clustered into 2 genotypes, G1 (90.1%, 91/101) and G3 (9.9%, 10/101). Hap1 was the most common haplotype (48.5%, 49/101). Hap9 were found in humans samples, indicating that sheep and cattle reservoir human CE. It is indicate that E. granulosus may impact on control of CE in livestock and humans in the region.

유청단백 함유 체중조절용 식사대체제를 이용한 4주 다이어트 프로그램이 과체중 및 비만 여성의 체중, 체지방 및 체성분에 미치는 영향

석매주(Mei-Zhu Xi),장이림(Yi-Lin Zhang),최영빈(Young-Bin Choi),정기희(Gi-Hee Jeong),김건우(Gun-Woo Kim),박용우(Yong-Woo Park),이복희(Bog-Hieu Lee) 동아시아식생활학회 2016 동아시아식생활학회지 Vol.26 No.1