Study on the space frame structures incorporated with magnetorheological dampers

Fei-Hong Xu,Zhao-Dong Xu,Xiang-Cheng Zhang 국제구조공학회 2017 Smart Structures and Systems, An International Jou Vol.19 No.3

Magnetorheological damper has received significant attention in recent years due to the reason that it can offer adaptability of active control devices without requiring the associated large power sources. In this paper, performance tests on a MR damper are carried out under different currents, excitation amplitudes and frequencies, the damping characteristics and energy dissipation capacity of the MR damper are analyzed. Elasto-plastic dynamic analysis on a space frame structure incorporated with MR dampers is conducted, and numerical analysis results show that MR dampers can significantly mitigate the structural vibration responses. Finally, the genetic algorithm with the improved binary crossover and mutation technique is adopted to optimize the arrangement of MR dampers. Numerical results show that dynamic responses of the optimal controlled structure are mitigated more effectively.

Preparation and Characterization of Tributyrin Sub-micron Emulsion as Carrier for Paclitaxel

( Xiang Fei ),( Wen Ting Xu ),( Yuan Yue ),( Mi Kyung Lee ) 한국약제학회 2011 Journal of Pharmaceutical Investigation Vol.41 No.5

Paclitaxel is a well known anticancer agent and has been a pharmaceutical challenge because of its extremely poor water-solubility and susceptibility to the p-glycoprotein (p-gp)-mediated efflux in multi-drug resistant (MDR) cancer cells. Tributyrin (TB), a triglyceride with relatively short fatty acid chains, was chosen as solubilizing vehicle for paclitaxel based on the solubility study (26.6 mg/mL). Tributyrin (10%) o/w emulsion containing paclitaxel (5%), egg phosphatidylcholine (5%) and pegylated phospholipid (0.5%) was prepared by high pressure homogenization to obtain submicron- sized emulsion. The mean particle size of the resultant TB emulsion was 395.5 nm. Paclitaxel in TB emulsion showed higher anticancer activity against human breast cancer cell line, MCF-7, than free form delivered in DMSO solution. On the other hand, its anticancer activity was significantly reduced in MCF-7/ADR, a MDR variant cancer cell line of MCF- 7, and recovered by the presence of verapamil, suggesting of the susceptibility to the p-gp mediated efflux even though paclitaxel was encapsulated into emulsion. The TB emulsion showed great potential as a promising vehicle for water-insoluble anticancer agent, paclitaxel.

Cloning and Sequence Analysis of a Glyceraldehyde-3-phosphate Dehydrogenase Gene from Ganoderma lucidum

Xu Fei,Ming Wen Zhao,Yu Xiang Li 한국미생물학회 2006 The journal of microbiology Vol.44 No.5

A cDNA library of Ganoderma lucidum has been constructed using a Zap Express cloning vector. A glyceraldehyde-3-phosphate dehydrogenase gene (gpd) was isolated from this library by hybridization of the recombinant phage clones with a gpd-specific gene probe generated by PCR. By comparison of the cDNA and the genomic DNA sequences, it was found that the complete nucleotide sequence encodes a putative polypeptide chain of 338 amino acids interrupted by 6 introns. The predicted amino acid sequence of this gene shows a high degree of sequence similarity to the GPD proteins from yeast and filamentous fungi. The promoter region contains a CT-rich stretch, two CAAT boxes, and a consensus TATA box. The possibility of using the gpd promoter in the construction of new transformation vectors is discussed.

Cloning and Sequence Analysis of a Glyceraldehyde-3-phosphate Dehydrogenase Gene from Ganoderma lucidum

Fei Xu,Zhao Ming Wen,Li Yu Xiang The Microbiological Society of Korea 2006 The journal of microbiology Vol.44 No.5

A cDNA library of Ganoderma lucidum has been constructed using a Zap Express cloning vector. A glyceraldehyde-3-phosphate dehydrogenase gene (gpd) was isolated from this library by hybridization of the recombinant phage clones with a gpd-specific gene probe generated by PCR. By comparison of the cDNA and the genomic DNA sequences, it was found that the complete nucleotide sequence encodes a putative polypeptide chain of 338 amino acids interrupted by 6 introns. The predicted amino acid sequence of this gene shows a high degree of sequence similarity to the GPD proteins from yeast and filamentous fungi. The promoter region contains a CT-rich stretch, two CAAT boxes, and a consensus TATA box. The possibility of using the gpd promoter in the construction of new transformation vectors is discussed.

Preliminary Results of a Phase I/II Study of Simultaneous Boost Irradiation Radiotherapy for Locally Advanced Nasopharyngeal Carcinoma

Xiang, Li,Wang, Yan,Xu, Bing-Qing,Wu, Jing-Bo,Xia, Yun-Fei Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Background: The purpose of this article is to present preliminary results of simultaneous boost irradiation radiotherapy for locally advanced nasopharyngeal carcinoma (NPC). Methods: Fifty-eight patients who underwent simultaneous boost irradiation radiotherapy for NPC in Cancer Center of Sun Yat-sen University between September 2004 and December 2009 were eligible. Acute and late toxicities were scored weekly according to the Radiation Therapy Oncology Group (RTOG) acute and late radiation morbidity scoring schemes. An especial focus was on evidence of post-radiation brain injury. Also quality of life was analysed according to the EORTC (European Organisation for Research and Treatment of Cancer) recommendations. Discrete variables were compared by ${\chi}^2$ test. The Kaplan-Meier method was used to calculate the survival rates and generate survival curves. Results: A total of 58 patients with a mean follow-up time of 36 months completed clinical trials.Fifty-seven patients (98.3) achieved complete remission in the primary sites and cervical lymph nodes, with only one patient (1.7%) showing partial remission.The most frequently observed acute toxicities during the concurrent chemoradiotherapy were mucositis and leucopenia. Four patients (6.9%) had RTOG grade 3 mucositis, whereas four patients (6.9%) had grade 3 leucopenia. No patient had grade 4 acute toxicity. Three (5.17%) of the patients exhibited injury to the brain on routine MRI examination, with a median observation of 32 months (range, 25-42months). All of them were RTOG grade 0. The 3-year overall, regional-free and distant metastasis-free survival rates were 85%, 94% and 91%, respectively. Conclusion: Simultaneous boost irradiation radiotherapy is feasible in patients with locally advanced nasopharyngeal carcinoma. The results showed excellent local control and overall survival, with no significant increase the incidence of radiation brain injury or the extent of damage. A larger population of patients and a longer follow-up period are needed to evaluate ultimate tumor control and late toxicity.

Dual Effect of Hepatic Macrophages on Liver Ischemia and Reperfusion Injury during Liver Transplantation

Tian-Fei Lu,Tai-Hua Yang,Cheng-Peng Zhong,Chuan Shen,Wei-Wei Lin,Guang-Xiang Gu,Qiang Xia,Ning Xu 대한면역학회 2018 Immune Network Vol.18 No.3

Ischemia-reperfusion injury (IRI) is a major complication in liver transplantation (LT) and it is closely related to the recovery of grafts' function. Researches has verified that both innate and adaptive immune system are involved in the development of IRI and Kupffer cell (KC), the resident macrophages in the liver, play a pivotal role both in triggering and sustaining the sterile inflammation. Damage-associated molecular patterns (DAMPs), released by the initial dead cell because of the ischemia insult, firstly activate the KC through pattern recognition receptors (PRRs) such as toll-like receptors. Activated KCs is the dominant players in the IRI as it can secret various pro-inflammatory cytokines to exacerbate the injury and recruit other types of immune cells from the circulation. On the other hand, KCs can also serve in a contrary way to ameliorate IRI by upregulating the anti-inflammatory factors. Moreover, new standpoint has been put forward that KCs and macrophages from the circulation may function in different way to influence the inflammation. Managements towards KCs are expected to be the effective way to improve the IRI.

Influence of loading and unloading of hydraulic support on the caving property of top coal

Huayong Lv,Fei Liu,Xu Gao,Tao Zhou,Xiang Yuan 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.48 No.1

The caving property of top coal is a key factor to the success of top coal caving mining. The influence law of cyclic loading and unloading of hydraulic support on top coal caving is of great significance to improve the recovery rate of top coal. The similar simulation methods were used to study the dynamic evolution of the top coal cracks under the multi-cycle action of the support, and the parameters of top coal cracks were analyzed quantitatively in this paper. The results show that the top coal cracks can be divided into horizontal cracks and vertical cracks under the cyclic loading and unloading of the support. With the increase of the times of the support cycles loading and unloading, the load on the support decreases, the fractal dimension of the cracks increases, the number and total length of the top coal cracks increases, and the top coal caving is getting better. With the increase of the times of multi-cycle loading and unloading, the fractal dimension, total crack length and crack rate of top coal show a trend of rapid increase first and then increase slowly. Both the total length of the top coal cracks and the crack rate basically show linear growth with the change of the fractal dimension. The top coal caving can be well improved and the coal resource recovery rate increased through the multi-cycle loading and unloading.

Ellipsometric Study of the Optical Properties of Silicon-Based Si:SiO2 Composite Thin Films under Different Annealing Temperatures

Bin Sun,Yu-Xiang Zheng,Cong-Hui Xu,Liang-Yao Chen,Peng Zhou,Yue-Rui Chen,Yu-Fei Kong 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.5I

In our work, silicon and silica composite .lms were prepared by using a magnetron sputtering method, and the samples were annealed in the temperature range between 200 ±C and 600 ±C. After annealing, the samples were investigated by spectroscopic ellipsometry (SE), and the SE spectra were measured in the range of 1.5 eV ≫ 4.5 eV with a dual-rotating-element ellipsometer. In order to investigate the microstructure information of the .lm by .tting the SE spectra using the eective- medium approximation (EMA), we modeled the whole .lm by using a multilayer optical model including a surface oxide layer, a composite layer, and substrate layer. We used dierent mixtures to describe the composite layer, and .nally we found that a mixture of amorphous silicon (a-Si), polycrystalline silicon (p-Si), and silicon dioxide had the best .t to the SE spectra. Whereafter, we studied the dependences of the surface roughness, the layer structure, and the composition on the dierent annealing temperatures and found that with increasing annealing temperature, the surface oxide layer grew in thickness, the silicon dioxide maintained its volume fraction, and a-Si transferred to p-Si.

Modeling, Preparation, and Elemental Doping of Li₇La₃Zr₂O₁₂ Garnet-Type Solid Electrolytes: A Review

Cao, Shiyu,Song, Shangbin,Xiang, Xing,Hu, Qing,Zhang, Chi,Xia, Ziwen,Xu, Yinghui,Zha, Wenping,Li, Junyang,Gonzale, Paulina Mercedes,Han, Young-Hwan,Chen, Fei The Korean Ceramic Society 2019 한국세라믹학회지 Vol.56 No.2

Recently, all-solid-state batteries (ASSBs) have attracted increasing interest owing to their higher energy density and safety. As the core material of ASSBs, the characteristics of the solid electrolyte largely determine the performance of the battery. Thus far, a variety of inorganic solid electrolytes have been studied, including the NASICON-type, LISICON-type, perovskite-type, garnet-type, glassy solid electrolyte, and so on. The garnet Li₇La₃Zr₂O₁₂ (LLZO) solid electrolyte is one of the most promising candidates because of its excellent comprehensively electrochemical performance. Both, experiments and theoretical calculations, show that cubic LLZO has high room-temperature ionic conductivity and good chemical stability while contacting with the lithium anode and most of the cathode materials. In this paper, the crystal structure, Li-ion transport mechanism, preparation method, and element doping of LLZO are introduced in detail based on the research progress in recent years. Then, the development prospects and challenges of LLZO as applied to ASSBs are discussed.

Effects of Age, Breast Density and Volume on Breast Cancer Diagnosis: A Retrospective Comparison of Sensitivity of Mammography and Ultrasonography in China's Rural Areas

Wang, Feng-Liang,Chen, Fei,Yin, Hong,Xu, Nan,Wu, Xiao-Xiang,Ma, Jing-Jing,Gao, Shen,Tang, Jin-Hai,Lu, Cheng Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

Purpose: Mammography has been confirmed as the only effective mode to improve the prognosis of patients with breast cancer in Western developed countries, but might not be a good choice in other areas of the world. One of the major challenges in China is to determine an optimal imaging modality for breast cancer screening. This study was designed to clarify the sensitivity of ultrasonography compared with that of mammography in rural China. Methods: We retrospectively studied the sensitivity of mammography and ultrasonography based on 306 breast cancer patients detected by the program of "screening for cervical cancer and breast cancer" performed in Chinese rural areas between January 2009 and December 2011, and analyzed the effects of age, breast density and volume on the sensitivity. Results: Stratified analysis showed that the sensitivity of breast ultrasonography was significantly higher than that of mammography in premenopausal patients (81.4% vs. 61.1%, p=0.02), in women ${\leq}$ 55 years of age (82.2% vs. 63.4%, p<0.01), in the high breast density group (American College of Radiology [ACR] levels 3-4) (85.9% vs. 60.6%, p<0.01) and in the small breast volume group (${\leq}$ 400 ml) (87.1% vs. 66.7%, p<0.01). Age had a significant effect on sensitivity of mammography (breast density and volume-adjusted odds ratio, 6.39; 95% confidence interval, 2.8-14.4 in age group > 55 compared to age group ${\leq}$ 45), but not that of ultrasonography. Neither breast density nor volume had significant effect on sensitivity of mammography or ultrasonography. Conclusions: Ultrasonography is more sensitive than mammography in detecting breast cancer in women under 55 year-old Chinese, especially in those with high-density and relatively small breasts.