The Damage Criterion Affecting Life Prediction of Fiber-Reinforced Al–Li Alloy Laminates Under Spectrum Loading

Meng Weiying,Li Yupeng,Zhang Xiaochen,Shi Huaitao,Zhang Yu,Lv Xiao 한국항공우주학회 2020 International Journal of Aeronautical and Space Sc Vol.21 No.4

Fiber metal laminates, as the new generation of aircraft structural materials, are widely concerned by material researcher. This paper presents a study on the life prediction problems of fiber-reinforced Al–Li alloy laminates under spectrum loading by applying the cumulative damage and residual strength models. Firstly, fatigue life performance of the laminate materials is tested under different loading cases. Then, the most advanced damage accumulation and residual strength models are summarized, which is applied to composite laminates. Some models are directly abandoned because the data needed for fitting model cannot be obtained by this experiment or the model formulation is prevented directly to the application for the spectrum blocks with free loading. Meanwhile, a cumulative damage model considering residual strength is modified accordingly based on the characteristics of life prediction under spectrum loading. To study the impacts of these models on the fatigue life prediction for fiber reinforced Al–Li alloy laminate under spectrum loading, the predicted accuracy of these models will be compared by applying them to life prediction problems of 2/1 laminate and 3/2 laminate. Results show that compared with other models, modified model improves the prediction accuracy especially for 3/2 laminate.

Tumor-Derived Transforming Growth Factor-β is Critical for Tumor Progression and Evasion from Immune Surveillance

Li, Zheng,Zhang, Li-Juan,Zhang, Hong-Ru,Tian, Gao-Fei,Tian, Jun,Mao, Xiao-Li,Jia, Zheng-Hu,Meng, Zi-Yu,Zhao, Li-Qing,Yin, Zhi-Nan,Wu, Zhen-Zhou Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Tumors have evolved numerous mechanisms by which they can escape from immune surveillance. One of these is to produce immunosuppressive cytokines. Transforming growth factor-${\beta}$(TGF-${\beta}$) is a pleiotropic cytokine with a crucial function in mediating immune suppression, especially in the tumor microenvironment. TGF-${\beta}$ produced by T cells has been demonstrated as an important factor for suppressing antitumor immune responses, but the role of tumor-derived TGF-${\beta}$ in this process is poorly understood. In this study, we demonstrated that knockdown of tumor-derived TGF-${\beta}$ using shRNA resulted in dramatically reduced tumor size, slowing tumor formation, prolonging survival rate of tumor-bearing mice and inhibiting metastasis. We revealed possible underlying mechanisms as reducing the number of myeloid-derived suppressor cells (MDSC) and $CD4^+Foxp3^+$ Treg cells, and consequently enhanced IFN-${\gamma}$ production by CTLs. Knockdown of tumor-derived TGF-${\beta}$ also significantly reduced the conversion of na$\ddot{i}$ve $CD4^+$ T cells into Treg cells in vitro. Finally, we found that knockdown of TGF-${\beta}$ suppressed cell migration, but did not change the proliferation and apoptosis of tumor cells in vitro. In summary, our study provided evidence that tumor-derived TGF-${\beta}$ is a critical factor for tumor progression and evasion of immune surveillance, and blocking tumor-derived TGF-${\beta}$ may serve as a potential therapeutic approach for cancer.

DEVELOPMENT OF CHINA LIGHT-DUTY VEHICLE TEST CYCLE

Yu Liu,Zhi Xin Wu,Hua Zhou,Han Zheng Nan Yu,Xiao Pan An,Jing Yuan Li,Meng Liang Li 한국자동차공학회 2020 International journal of automotive technology Vol.21 No.5

Driving cycles provide a basis for vehicle development and calibration and also serves as the foundation for energy consumption and emissions certification of vehicles. This paper presents the China Light-Duty Vehicle Test Cycle (CLTC) developed by the China Automotive Technology & Research Center (CATARC). First, the important steps and technical routes toward the CLTC development process are summarized. Second, the specific CLTC development process is presented in detail, including the data acquisition and data analysis procedures, weighting factor development and driving cycle construction. Then, the main driving characteristics of the New European Driving Cycle (NEDC), the Worldwide Harmonized Light-Duty Vehicles Test Cycle (WLTC), the Federal Test Procedure (FTP-75), the CLTC and the actual collected data are compared. The CLTC has low average speed, a high idle speed ratio and more frequent acceleration and deceleration characteristics. Finally, 70 vehicles are t ested based on the NEDC, WLTC, and CLTC according to their legislative procedures in the vehicle emission laboratories of the CATARC and the manufacturers. The results show that the CLTC’s fuel consumption is much higher than that of the NEDC and WLTC, and CLTC can effectively reflect the actual fuel consumption of users.

Slide Session : OS-GAS-05 ; Gastroenterology : 3-Mercaptopyruvate Sulfurtransferase Downregulation Ameliorates Hepatic Steatosis and Oxidative Stress Via Hydrogen Sulfi de Metabolism in Nonalcoholic Fatty Liver Disease

( Meng Li ),( Jiexia Ding ),( Xingyong Wan ),( Xi Jin ),( Shaohua Chen ),( Chaohui Yu ),( Youming Li ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: The mitochondrial enzyme 3-mercaptopyruvate sulfurtransferase (MPST) is a source of endogenous hydrogen sul.de (H2S), a gaseous signaling molecule implicated in a wide range of physiological processes. The mechanisms of pathogenesis underlying nonalcoholic fatty liver disease (NAFLD) remain unclear. The possible role of MPST in the development of NAFLD has never been investigated. Methods: The NAFLD cell model was established by treating L02 cells with free fatty acid (FFA) overload. A variety of cellular and molecular approaches were used to study the effects of MPST on hepatic steatosis, oxidative stress and inflammation involved in NAFLD. Results: After culturing L02 cells by FFA for 24h, we detected the increased protein level of MPST. MPST knockdown in L02 cells resulted in a marked decrease of lipid accumulation and downregulation of SREBP-1 pathway and melioration of oxdiative stress, embodied in decreased level of H2O2, MDA and IL-6, meanwhile, increased levels of ATP and MMP. Unexpectedly, we observed a significantly increased level of H2S after knockdown of MPST. And the expression of CSE was enhanced when the MPST was decreased. When the level of H2S was decreased, the TG and H2O2 content within FFA-induced hepatocytes were greatly raised. Meanwhile, we demonstrated the reversed expression of SREBP-1/ ACC pathway with the reduced level of H2S. Conclusions: We showed that MPST knockdown could stimulate the compensatory process of CSE, causing the increasing of H2S which is recently considered as a novel antioxidant gas. The increased endogenous H2S could improve hepatocyte steatosis and partly improve the process of oxidative stress and in. ammatory state of steatosis hepatocytes. MPST is implicated in NAFLD via its important H2S metabolism. It provided new insight into the pathogenic mechanisms of NAFLD, pointing to potential target for therapeutic strategy.

PM2.5 in poultry houses synergizes with Pseudomonas aeruginosa to aggravate lung inflammation in mice through the NF-κB pathway

Meng Li,Xiuli Wei,Youzhi Li,Tao Feng,Linlin Jiang,Hongwei Zhu,Xin Yu,Jinxiu Tang,Guozhong Chen,Jianlong Zhang,Xingxiao Zhang 대한수의학회 2020 Journal of Veterinary Science Vol.21 No.3

Background: High concentrations of particulate matter less than 2.5 µm in diameter (PM2.5) in poultry houses is an important cause of respiratory disease in animals and humans. Pseudomonas aeruginosa is an opportunistic pathogen that can induce severe respiratory disease in animals under stress or with abnormal immune functions. When excessively high concentrations of PM2.5 in poultry houses damage the respiratory system and impair host immunity, secondary infections with P. aeruginosa can occur and produce a more intense inflammatory response, resulting in more severe lung injury. Objectives: In this study, we focused on the synergistic induction of inflammatory injury in the respiratory system and the related molecular mechanisms induced by PM2.5 and P. aeruginosa in poultry houses. Methods: High-throughput 16S rDNA sequence analysis was used for characterizing the bacterial diversity and relative abundance of the PM2.5 samples, and the effects of PM2.5 and P. aeruginosa stimulation on inflammation were detected by in vitro and in vivo. Results: Sequencing results indicated that the PM2.5 in poultry houses contained a high abundance of potentially pathogenic genera, such as Pseudomonas (2.94%). The lung tissues of mice had more significant pathological damage when co-stimulated by PM2.5 and P. aeruginosa, and it can increase the expression levels of interleukin (IL)-6, IL-8, and tumor necrosis factor-α through nuclear factor (NF)-κB pathway in vivo and in vitro. Conclusions: The results confirmed that poultry house PM2.5 in combination with P. aeruginosa could aggravate the inflammatory response and cause more severe respiratory system injuries through a process closely related to the activation of the NF-κB pathway.

A (n, t, n) Verifiable Multi-secret Sharing Scheme with Secure Secret Reconstruction

Li Meng,Qu Shaoyun,Xun Tiantian,Yu Jia 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.1

Increased Progastrin-Releasing Peptide Expression is Associated with Progression in Gastric Cancer Patients

Li Li,Xiaodong Yin,Hai Meng,Juanyu Hu,Zhengqing Yu,Jianyong Xu 연세대학교의과대학 2020 Yonsei medical journal Vol.61 No.1

Purpose: The purpose of this study was to assess the diagnostic and prognostic value of serum progastrin-releasing peptide(ProGRP) in patients with gastric cancer (GC). Materials and Methods: A total of 150 patients with GC (89 males and 61 females) were recruited, including those with stage I(n=28), stage II (n=33), stage III (n=50), and stage IV (n=39) disease; 50 healthy controls and 66 patients with benign gastric diseaseswere also enrolled. Levels of serum ProGRP, carcinoembryonic antigen (CEA), and carbohydrate antigen 72-4 (CA72-4)were measured in all subjects. Results: Serum ProGRP levels were significantly higher in GC patients than in controls (p<0.001), and ProGRP was significantlycorrelated with tumor size, tumor node metastasis stage, differentiation, invasion depth, and lymph node metastasis (p< 0.005). ProGRP levels were significantly decreased after chemotherapy (p<0.001). Receiver operating characteristic curves revealed a sensitivityand specificity for serum ProGRP in GC of 85.9% and 81.2%, respectively. ProGRP levels were positively correlated withCA72-4 and CEA (r=0.792 and 0.688, p<0.05, respectively). Combined detection of ProGRP, CEA, and CA72-4 showed the best diagnosticpower for GC. Conclusion: ProGRP may be useful as a potential biomarker for GC diagnosis and therapy.

Potential of electroblown bioactive fibrous scaffoldsfor bone tissue engineering

Yu-Meng Li,Nandin Mandakhbayar,Ahmed El-Fiqi,Khandmaa Dashnyam,Jung-Hwan Lee,Hae-Won Kim 대한치과재료학회 2019 대한치과기재학회 학술대회 Vol.2019 No.11

ZmFKBP20-1 improves the drought and salt tolerance of transformed Arabidopsis

Yanli Yu,Yanjiao Li,Fengjuan Jia,Meng Zhao,Wencai Li,Qi Sun,Nana Li,Wenlan Li,Zhaodong Meng 한국식물학회 2017 Journal of Plant Biology Vol.60 No.6

FK506-binding proteins (FKBPs), which belongto the peptidyl-prolyl cis/trans isomerase superfamily, areinvolved in plant response to abiotic stresses. A number ofFKBP family genes have been isolated in plants, but littlehas been reported of FKBP genes in maize. In this study, adrought-induced FKBP gene, ZmFKBP20-1, was isolated frommaize and was characterized for its role in stress responsesusing gene expression, protein subcellular localization,transformation in Arabidopsis, expression patterns of thestress-responsive genes, and physiological parameter analysis. During drought and salt stresses, ZmFKBP20-1 transgenicArabidopsis plants exhibited enhanced tolerance, which wasconcomitant with the altered expression of stress/ABAresponsivegenes, such as COR15a, COR47, ERD10, RD22,KIN1, ABI1, and ABI2. The resistance characteristics ofZmFKBP20-1 overexpression were associated with a significantincrease in survival rate. These results suggested thatZmFKBP20-1 plays a positive role in drought and salt stressresponses in Arabidopsis and provided new insights into themechanisms of FKBP in response to abiotic stresses inplants.

Preparation of 5-fluorouracil-loaded Nanoparticles and Study of Interaction with Gastric Cancer Cells

Fan, Yu-Ling,Fan, Bing-Yu,Li, Qiang,Di, Hai-Xiao,Meng, Xiang-Yu,Ling, Na Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

Aims: To prepare 5-fluorouracil (5-Fu) nanoparticles with higher encapsulation efficiency and drug loading, and then investigate interaction with the SGC-7901 gastric cancer cell line. Materials and Methods: Prescription was optimized by orthogonal experiments, the encapsulation efficiency and loading capacity were tested by high-performance liquid chromatography, and inhibition of proliferation by 5-Fu nanoparticles and 5-Fu given to cells for 24, 48 and 72 hours was investigated by methyl thiazolyl tetrazolium assay (MTT). In addition, 5-Fu nanoparticles were labeled by fluorescein isothiocyanate (FITC), and absorption into cells was tested by flow cytometry. Results: The optimal conditions for preparation were concentrations of 5-Fu of 5mg/ml, of $CaCl_2$ of 60 mg/ml and of chitosan of 2 mg/ml. With a stirring speed of 1200rpm, encapsulation efficiency of 5-Fu nanoparticles was $55.4{\pm}1.10%$ and loading capacity was $4.22{\pm}0.14%$; gastric cancer cells were significantly inhibited by 5-Fu nanoparticles in a time and concentration dependent manner, and compared to 5-Fu with slower drug release, in a certain concentration range, inhibition with 5-Fu nanoparticles was stronger. 5-Fu nanoparticles were absorbed by the cells in line with the concentration. Conclusions: 5-Fu nanoparticles can inhibit growth of gastric cancer cells in vitro to a greater extent than with 5-Fu with good adsorption characteristics, supporting feasibility as a carrier.