Study and Optimization of Structural Parametrics of Oil Seal by Response Surface Method

Fu-Ying Zhang,Jian-Lei Chen,Tian-Tian Li,Yu-Fei Zhang 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.2

The effect of structural parameters such as contact width, low-angle, high-angle, interference and waist depth on the sealing performance of rotary lip seal was analyzed by finite element method. Based on the macroscopic pumping effect model of the rotary shaft lip seal and the pumping rate equation, the influence of structural parameters on pumping rate was calculated and analyzed. The structural and operational parameters of lip seal were optimized by the response surface method. 32 kinds of the model were made by compounding levels on each factor, and the response surface regression characteristics of each model are analyzed. The results show that low-angle, high-angle and interference are the main factors that influence significantly the seal performance of rotary shaft lip seal, and contact width, low-angle and high-angle are major influential factors for pumping effect. Therefore, these factors are considered as the most important factors for an optimum design of the rotary shaft lip seal. The optimal conditions are obtained, and the results are also verified by analytical methods.

irrE, an Exogenous Gene from Deinococcus radiodurans, Improves the Growth of and Ethanol Production by a Zymomonas mobilis Strain Under Ethanol and Acid Stresses

( Ying Zhang ),( Rui Qiang Ma ),( Zhong Lin Zhao ),( Zheng Fu Zhou ),( Wei Lu ),( Wei Zhang ),( Ming Chen ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.7

Induction of Apoptosis by Chelerythrine Chloride through Mitochondrial Pathway and Bcl-2 Family Proteins in Human Hepatoma SMMC-7721 Cell

Zheng-fu Zhang,Ying Guo,Jian-bin Zhang,Xiong-hui Wei 대한약학회 2011 Archives of Pharmacal Research Vol.34 No.5

The objective of this study was to evaluate the antitumor activity of chelerythrine chloride (CHE) and investigate its potential apoptotic induction mechanism in SMMC-7721 cells. Our results suggested that the proliferation of SMMC-7721 cells was inhibited by CHE in a time and dose dependent manner, with a significant accumulation in S phase, and the cells exhibited typical apoptotic features. Moreover, CHE remarkably induced apoptosis by disruption of the mitochondrial membrane potential, release of Cyt-c, activation of caspase-3, and cleavage of poly-ADP-ribose polymerase in a dose dependent manner. Furthermore, the expression of Bcl-xl was downregulated while Bax and Bid expression was upregulated, and no variation was found for Bcl-2. These results indicated that CHE may play an important role in suppression of tumor growth by inducing apoptosis in human hepatoma cells via the activation of a mitochondrial pathway and regulating the expression of Bcl-2 family proteins.

rs10505474 and rs7837328 at 8q24 Cumulatively Confer Risk of Prostate Cancer in Northern Han Chinese

Zhang, Lin-Lin,Sun, Liang,Zhu, Xiao-Quan,Xu, Yong,Yang, Kuo,Yang, Fan,Yang, Yi-Ge,Chen, Guo-Qiang,Fu, Ji-Cheng,Zheng, Chen-Guang,Li, Ying,Mu, Xiao-Qiu,Shi, Xiao-Hong,Zhao, Fan,Wang, Fei,Yang, Ze,Wang, Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

Aims: Genome-wide association studies (GWAS) have identified several risk variants for prostate cancer (pCa) mainly in Europeans, which need to be further verified in other racial groups. We selected six previously identified variants as candidates and to define the association with PCa in Northern Han Chinese. Methods: 749 subjects from Beijing and Tianjin in Northern China were included. Six variants (rs10505474, rs7837328, rs4242384, rs7813, rs486907 and rs1058205) were genotyped by high resolution melting (HRM) assays. The individual and cumulative contribution for of the risk of PCa and clinical covariates were analyzed. Results: Among the six candidate variants, onlyrs10505474, and rs7837328, both locating at 8q24 region, were associated with PCa in our population.rs10505474 (A) was associated with PCa ($OR_{recessive}=1.56$, p=0.006); and rs7837328 (A) was associated with PCa ($OR_{dominant}=1.38$, p=0.042/$OR_{recessive}=1.99$, p=0.003). Moreover, we observed a cumulative effects between them ($p_{trend}=2.58{\times}10^{-5}$). The joint population attributable risk showed the two variants might account for 71.85% of PCa risk. In addition, we found the homozygotes of rs10505474 (A) and rs7837328 (A) were associated with PCa clinical covariants (age at onset, tumor stage, respectively) ($p_{age}=0.046$, $P_{tumorstage}=0.048$). Conclusion: rs10505474 (A) and rs7387328 (A) at 8q24 are associated with PCa and cumulatively confer risk, suggesting the two variations could determine susceptibility to PCa in the Northern Chinese Han population.

Sorafenib Continuation after First Disease Progression Could Reduce Disease Flares and Provide Survival Benefits in Patients with Hepatocellular Carcinoma: a Pilot Retrospective Study

Fu, Si-Rui,Zhang, Ying-Qiang,Li, Yong,Hu, Bao-Shan,He, Xu,Huang, Jian-Wen,Zhan, Mei-Xiao,Lu, Li-Gong,Li, Jia-Ping Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

Background: Sorafenib is a promising drug for advanced hepatocellular carcinoma (HCC); however, treatment may be discontinued for multiple reasons, such as progressive disease, adverse events, or the cost of treatment. The consequences of sorafenib discontinuation and continuation are uncertain. Materials and Methods: We retrospectively analyzed 88 HCC patients treated with sorafenib from July 2007 to January 2013. Overall survival (OS), post-disease progression overall survival (pOS), and time to disease progression (TTP) were compared for survival analysis. Cox proportional hazard regression was performed to assess the effect of important factors on OS in the overall patient population and on pOS in patients who continued sorafenib treatment. Results: Sorafenib was discontinued and continued in 24 and 64 patients, respectively. The median OS (355 vs 517 days respectively; p=0.015) and median post-PD OS (260 vs 317 days, respectively; p=0.020) were statistically different between the discontinuation and continuation groups. Neither the median time to first PD nor the time to second PD were significantly different between the 2 groups. In the discontinuation group, 3 of the 24 patients (12.5%) suffered disease outbreaks. In Cox proportional hazard regression analysis after correction for confounding factors, BCLC stage (p=0.002) and PD site (p=0.024) were significantly correlated with pOS in patients who continued sorafenib treatment. Conclusions: Sorafenib discontinuation may cause HCC flares or outbreaks. It is advisable to continue sorafenib treatment after first PD, particularly in patients with Barcelona Clinic Liver Cancer stage B disease or only intrahepatic PD.

NANOTOXICITY OF MULTIWALL CARBON NANOTUBES TO A549 CELLS IN VITRO

FU-DE WANG,Ying Tang,Yong Ji Yang,CHAN JIN,HUA ZHANG,HAO LIANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.2

Multiwall carbon nanotubes (MWCNTs) have been widely applied in many ¯elds due to theexcellent physical and chemical properties. As the production and applications of nanotubesexpand, public concern about their potential risks to human health has also raised. Cytotoxicityof MWCNTs was evaluated in this study using a cultured human epithelial cell line A549. Uptakeof MWCNTs by cultured A549 cells was observed by TEM imaging. Dose-dependent decrease ofcell viability showed the cytotoxicity of MWCNTs. Signi¯cant reactive oxygen species (ROS)generation and GSH depletion which reduced the cellular antioxidant level could be the majorfactor of cytotoxicity induced by MWCNTs. MWCNTs seemed to trigger the activation of cellautophagy with the intracellular ATG16L1 level increase as a defense mechanism.

Study of the flow around a cylinder from the subcritical to supercritical regimes

Zhang, Xian-Tao,Li, Zhi-Yu,Fu, Shi-Xiao,Ong, Muk Chen,Chen, Ying Techno-Press 2014 Ocean systems engineering Vol.4 No.3

The objective of the present simulations is to evaluate the applicability of the standard $k-{\varepsilon}$ turbulence model in engineering practice in the subcritical to supercritical flow regimes. Two-dimensional numerical simulations of flow around a circular cylinder at $Re=1{\times}10^5$, $5{\times}10^5$ and $1{\times}10^6$, had been performed using Unsteady Reynolds-Averaged Navier Stokes (URANS) equations with the standard $k-{\varepsilon}$ turbulence model. Solution verification had been studied by evaluating grid and time step size convergence. For each Reynolds number, several meshes with different grid and time step size resolutions were chosen to calculate the hydrodynamic quantities such as the time-averaged drag coefficient, root-mean square value of lift coefficient, Strouhal number, the coefficient of pressure on the downstream point of the cylinder, the separation angle. By comparing the values of these quantities of adjacent grid or time step size resolutions, convergence study has been performed. Solution validation is obtained by comparing the converged results with published numerical and experimental data. The deviations of the values of present simulated quantities from those corresponding experimental data become smaller as Reynolds numbers increases from $1{\times}10^5$ to $1{\times}10^6$. This may show that the standard $k-{\varepsilon}$ model with enhanced wall treatment appears to be applicable for higher Reynolds number turbulence flow.

Behavior of improved through-diaphragm connection to square tubular column under tensile loading

Ying Qin,Jing-Chen Zhang,Peng Shi,Yi-Fu Chen,Yao-Han Xu,Zuo-Zheng Shi 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.68 No.4

Square tubular columns are commonly used in moment resisting frames, while through-diaphragm connection is the most typical configuration detail to connect the H-shaped beam to the column. However, brittle fracture normally occurs at the complete joint penetration weld between the beam flange and the through-diaphragm due to the stress concentration caused by the geometrical discontinuity. Accordingly, three improved types of through-diaphragm are presented in this paper to provide smooth force flow path comparing to that of conventional connections. Tensile tests were conducted on four specimens and the results were analyzed in terms of failure modes, load-displacement response, yield and ultimate capacity, and initial stiffness. Furthermore, strain distributions on the through-diaphragm, the beam flange plate, and the column face were comprehensively evaluated and discussed. It was found that all the proposed three types of improved through-diaphragm connections were able to reduce the stress concentration in the welds between the beam flange and the through-diaphragm. Furthermore, the stress distribution in connection with longer tapered through-diaphragm was more uniform.

Impact of wilting and additives on fermentation quality and carbohydrate composition of mulberry silage

Zhang, Ying Chao,Wang, Xue Kai,Li, Dong Xia,Lin, Yan Li,Yang, Fu Yu,Ni, Kui Kui Asian Australasian Association of Animal Productio 2020 Animal Bioscience Vol.33 No.2

Objective: The objective of this study was to investigate the effects of wilting and additives on the fermentation quality, structural and non-structural carbohydrate composition of mulberry silages. Methods: The selected lactic acid bacteria strains Lactobacillus plantarum 'LC279063' (L1), commercial inoculant Gaofuji (GF), and Trichoderma viride cellulase (CE) were used as additives for silage preparation. Silage treatments were designed as control (CK), L1, GF, or CE under three wilting rates, that is wilting for 0, 2, or 4 hours (h). After ensiling for 30 days, the silages were analyzed for the chemical and fermentation characteristics. Results: The results showed that wilting had superior effects on increasing the non-structural carbohydrate concentration and degrading the structural carbohydrate. After ensiling for 30 days, L1 generally had a higher fermentation quality than other treatments, indicated by the lower pH value, acetic acid, propionic acid and ammonia nitrogen (NH₃-N) content, and the higher lactic acid, water soluble carbohydrate, glucose, galactose, sucrose, and cellobiose concentration (p<0.05) at any wilting rate. Wilting could increase the ratio of lactic acid/acetic acid and decrease the content of NH₃-N. Conclusion: The results confirmed that wilting degraded the structural carbohydrate and increased the non-structural carbohydrate; and L1 exhibited better properties in improving fermentation quality and maintaining a high non-structural carbohydrates composition compared with the other treatments.

Impact of Global and Gene-Specific DNA Methylation in de Novo or Relapsed Acute Myeloid Leukemia Patients Treated with Decitabine

Zhang, Li-Ying,Yuan, You-Qing,Zhou, Dong-Ming,Wang, Zi-Yan,Ju, Song-Guang,Sun, Yu,Li, Jun,Fu, Jin-Xiang Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.1

In this investigation, global DNA methylation patterns and the specific methylation status of 5 genes were studied in DNA from peripheral blood (PB) and impact on progression free survival (PFS) and overall-survival (OS) in patients with de novo or relapsed acute myeloid leukemia (AML) treated with decitabine-based regimens waas assessed. DNA was isolated from PB samples at the time of -1, 1, and 7 days of chemotherapy. Global methylation was determined by ELISA, and the CpG island DNA methylation profile of 5 genes using a DNA methylation PCR system. Our data demonstrated that patients with a high level of 5-mC had a poor prognosis after demethylation therapy and those who have low levels of 5-mC in PB achieved higher CR and better SO, but there was no significant correlation found between the 5-mC levels and other clinical features before treatment except the disease status. Higher methylation status of Sox2 and Oct4 genes was associated with differential response to demethylation therapy. A relatively low methylation percentage in one or both of these two genes was also associated with longer OS after decitabine based chemotherapy. We also suggest that global DNA and Oct-4/Sox2 methylation might impact on the pathogenesis of leukemia and play an important role in the initiation and progression. Moreover, dynamic analysis of 5-mC and Oct-4/Sox2 in peripheral blood nucleated cells of leukemia patients may provide clues to important molecular diagnostic and prognostic targets.