A new algorithm to solve meshing-in impact considering the measured pitch error and to investigate its influence on the dynamic characteristics of a gear system

Fang Guo,Zong-De Fang 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.3

To study the actual changing rule of the meshing-in impact considering the measured pitch error and the effect on the dynamic characteristics of a gear system, this paper presents a new algorithm to calculate the meshing-in impact considering the measured pitch error. Based on the tooth contact analysis and loaded tooth contact analysis considering the measured pitch error, the algorithm can determine the exact original position where each mating tooth pair comes into contact in the process of gear transmission. Furthermore, we consider the meshing-in impact as dynamic excitation and simulate the dynamic response of the gear system with or without this excitation. The simulation result is expressed in time and frequency domains, phase plane plots and Poincaré maps. By using the wavelet packet transformation, the impact feature is extracted from the vibration response of the gear system.

Dichloromethane fraction of <i>Asiasarum heterotropoides</i> induces S phase arrest and apoptosis in KB oral epithelial carcinoma cells

Guo, Hui-Fang,Wang, Myeong-Hyeon EDITIONS SCIENTIFIQUES ELSEVIER 2017 BIOMEDICINE AND PHARMACOTHERAPY Vol.89 No.-

<P><B>Abstract</B></P> <P>We investigated the anti-cancer activity and molecular mechanism of dichloromethane fraction (DCM-AH) of ethanolic extract from <I>Asiasarum heterotropoides</I> radix. The KB cancer cells and HEK293 cells were exposed to DCM-AH in the same condition and found the cell viability of KB cell decreased significantly while the HEK293 cell showed a slight reduction. This finding suggested DCM-AH performed an anti-cancer activity in a dose and time dependent manner. As evidence for the DCM-AH inhibited the proliferation via modulating the cell cycle, flow cytometry and Western blot were conducted, it induced cell S phase arrest by upregulation of p21, p53, and cyclin E1 along with the downregulation of cyclin A2 and D1. Besides, it inhibited the proliferation of KB cells by triggering apoptosis, the stimulation of 4μg/mL DCM-AH obviously induced DNA condensation with an apoptotic rate of 31.2%. Undergoing mechanism was detected by Western blot, the upregulated expression of Bax, cleaved caspase-3, and -9 meantime downregulation of Bcl-2 explained it induced apoptosis by the intrinsic pathway.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A REVIEW OF STUDIES ON OCEAN TIDES AND MEAN SEA LEVEL IN CHINA

Guo Hong Fang,Wen Zhen Zheng 한국해안해양공학회 1999 학술강연회 발표논문초록집 Vol.1 No.1

The observation, analysis, prediction and dynamical studies on ocean tides and tidal currents in China in the recent 50 years are reviewed in the present paper. The major achievements and problems are reported. During recent 50 years, many tidal stations have been established and many short-period current observations have been carried out. The confusion in gauge zero existing in historical tidal data is considered as a most serious problem, and long-period current observations are still limited. Methods for analyzing and predicting tides and tidal currents have been developed. Tide and tidal current tables and charts published are sufficient for practical applications. Progresses in theoretical studies have also been achieved, in particular, on the effects of the friction on tides and tidal currents. Numerical modeling has become a popular measure in tidal prediction. Many studies on relative sea level rise have been carried out. Most of investigations indicate that the rising rates are around zero for the northern China coast and in the range of 1-2 ㎜/a for the southern China coast. However, acquisition of more reliable long-term sea level data is still required.

The effect of cyfluthrin on testis inhibin B in rats and the intervention of Lycium barbarum polysaccharide

Guo Xin,Xie Yong-Xin,Guo Chen,Wei Jing-Lin,Yang Hui-Fang 대한독성 유전단백체 학회 2021 Molecular & cellular toxicology Vol.17 No.2

Background In recent years, studies have shown that cyfluthrin is harmful to the reproductive system. Lycium barbarum polysaccharide may be a protective agent. Objective To investigate the effect of cyfluthrin (Cy) on testosterone B (inhibin B, INHB) in male rats and the intervention of Lycium barbarum polysaccharide (LBP). Results Compared with the control group, the mRNA and protein expression levels of INH α and INH βB in the testis tissue decreased, and the difference was statistically significant (P < 0.05). The LBP intervention group can significantly increase the expression level, and the difference is statistically significant (P < 0.05). Conclusion The decrease of INHα and INHβB expression caused by Cy exposure indicates that Cy has a toxic effect on the testis of rats, and the addition of LBP has a certain protective effect on the testis of rats. Background In recent years, studies have shown that cyfluthrin is harmful to the reproductive system. Lycium barbarum polysaccharide may be a protective agent. Objective To investigate the effect of cyfluthrin (Cy) on testosterone B (inhibin B, INHB) in male rats and the intervention of Lycium barbarum polysaccharide (LBP). Results Compared with the control group, the mRNA and protein expression levels of INH α and INH βB in the testis tissue decreased, and the difference was statistically significant (P < 0.05). The LBP intervention group can significantly increase the expression level, and the difference is statistically significant (P < 0.05). Conclusion The decrease of INHα and INHβB expression caused by Cy exposure indicates that Cy has a toxic effect on the testis of rats, and the addition of LBP has a certain protective effect on the testis of rats.

A Nested OGCM Simulations with Restart Dataset : Strategy for Simulating Fine Structures of Circulation for NW Pacific

Guo Hong Fang,최병호,Ze Xun Wei,Young Jin Choi 한국해안해양공학회 2000 한국해안·해양공학발표논문집 Vol.11 No.1

Prognostic Evaluation of Categorical Platelet-based Indices Using Clustering Methods Based on the Monte Carlo Comparison for Hepatocellular Carcinoma

Guo, Pi,Shen, Shun-Li,Zhang, Qin,Zeng, Fang-Fang,Zhang, Wang-Jian,Hu, Xiao-Min,Zhang, Ding-Mei,Peng, Bao-Gang,Hao, Yuan-Tao Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

Objectives: To evaluate the performance of clustering methods used in the prognostic assessment of categorical clinical data for hepatocellular carcinoma (HCC) patients in China, and establish a predictable prognostic nomogram for clinical decisions. Materials and Methods: A total of 332 newly diagnosed HCC patients treated with hepatic resection during 2006-2009 were enrolled. Patients were regularly followed up at outpatient clinics. Clustering methods including the Average linkage, k-modes, fuzzy k-modes, PAM, CLARA, protocluster, and ROCK were compared by Monte Carlo simulation, and the optimal method was applied to investigate the clustering pattern of the indices including platelet count, platelet/lymphocyte ratio (PLR) and serum aspartate aminotransferase activity/platelet count ratio index (APRI). Then the clustering variable, age group, tumor size, number of tumor and vascular invasion were studied in a multivariable Cox regression model. A prognostic nomogram was constructed for clinical decisions. Results: The ROCK was best in both the overlapping and non-overlapping cases performed to assess the prognostic value of platelet-based indices. Patients with categorical platelet-based indices significantly split across two clusters, and those with high values, had a high risk of HCC recurrence (hazard ratio [HR] 1.42, 95% CI 1.09-1.86; p<0.01). Tumor size, number of tumor and blood vessel invasion were also associated with high risk of HCC recurrence (all p< 0.01). The nomogram well predicted HCC patient survival at 3 and 5 years. Conclusions: A cluster of platelet-based indices combined with other clinical covariates could be used for prognosis evaluation in HCC.

The effects of MCM-41’s calcination temperature on the structure and hydrodenitrogenation over NiW catalysts

Fang Guo,Zegang Qiu,Liangfu Zhao,Shaoqing Guo,Xian-Xian Wei,Xiaoxiao Wang,Hongwei Xiang 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.11

MCM-41 was calcined at 500, 560, 600 or 650 oC. It was used as support for NiW catalysts of hydrodenitro-genation (HDN) for quinoline in order to investigate the influences of the MCM-41’s calcination temperature on thestructure and the HDN performance of NiW catalysts. The NiW catalysts were characterized by XRD, N2 adsorption-desorption, XPS, Raman, HRTEM and Py-IR techniques. The results showed that the surface area (SBET), the averagepore diameter (Dp) and the pore volume (Vp) of the MCM-41 increased with increase of the MCM-41’s calcinationtemperature. The high SBET , Dp and Vp were beneficial for the high dispersion of W species, the formation of appropriatenature of W species and acid sites on the catalysts. The HDN activity followed the order of NiW-650≈NiW-600>NiW-560>NiW-500, while the relative selectivity of HDN pathways was similar for all the catalysts.

Molecular phylogenetic analysis of key Jatropha species inferred from nrDNA ITS and chloroplast (trnL-F and rbcL) sequences

Fang Chen,Guo-ye Guo,Sheng-hua Wang,Ying Xu,Lin Tang,Mao-qun Yu 한국유전학회 2016 Genes & Genomics Vol.38 No.6

The genus Jatropha (Euphorbiaceae) contains species that are of significant economic and ornamental value. However, Jatropha breeding material is rather limited due to incomplete information regarding phylogenetic relationships among germplasm resources. Phylogenetic analyses were performed based on the internal transcribed spacer of nuclear ribosomal DNA (nrDNA ITS), two chloroplast regions (trnL-F and rbcL), and the combined (ITS?trnL-F?rbcL) dataset among twenty-five specimens representing six key Jatropha species. Phylogenetic relationships of Jatropha were well resolved between subgenus Curcas and subgenus Jatropha, and demonstrated the intermediate position of section Polymorphae among sections of both subgenera. Jatropha curcas and J. integerrima demonstrated a close phylogenetic relationship. The molecular data agreed with the morphological classification that recognized J. multifida and J. podagrica in sec. Peltatae. The distinct intraspecific divergence that occurred in J. curcas could be attributed to restricted gene flow caused by geographical isolation and different ecological conditions. Phylograms produced with trnL-F and rbcL sequence data suggested slow rates of sequence divergence among Jatropha spp., while the ITS gene tree had good resolution suggesting high genetic variation of ITS among Jatropha species.

Comparative Studies on Two Fluoro-Substituted 2-Pyrazoline Derivatives with Experimental and Theoretical Methods

Guo, Huan-Mei,Wang, Xian,Jian, Fang Fang,Xiao, Hai Lian,Zhao, Pu Su Korean Chemical Society 2009 Bulletin of the Korean Chemical Society Vol.30 No.5

Two fluoro-substituted 2-pyrazoline derivatives, 1-phenyl-3-(4-methoxyphenyl)-5-(4-fluorophenyl)-2-pyrazoline (1) and 1-phenyl-3-(4-methoxyphenyl)-5-(2-fluoro-phenyl)-2-pyrazoline (2) have been synthesized and characterized by elemental analysis, IR, UV-Vis and fluorescence spectra. The crystal structure of 1 has been determined by X-ray single crystal diffraction. For the two compounds, density functional theory (DFT) calculations of the structures and natural population atomic charge analysis (NPA) have been performed at B3LYP/6-311G** level of theory. By using TD-DFT method, electron spectra of 1 and 2 have been predicted, which are very approximate with the experimental ones. Comparative studies on 1 and 2 indicate that the location change of fluorine atom in 5-position phenyl ring of 2-pyrazoline does not make significant change of geometries and electronic transition bands, but it leads to evident change of atomic charge distributions and peak intensities of UV and fluorescence spectra.

Isochaetomium A2, a new bis(naphthodihydropyran-4-one) with antimicrobial and immunological activities from fungus Chaetomium microcephalum

Guo-Bo Xu,Tao Yang,Jin-ku Bao,Dong-Mei Fang,Guo-You Li 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.5

Isochaetomium A2 (1), a new bis(naphthodihydropyran-4-one), along with chaetochromins A (2) and B(3), was isolated from the solid-state fermented rice cultureof Chaetomium microcephalum. The structure of compound1 was elucidated on the basis of 1D and 2D NMRspectral data, and the relative configuration was confirmedby CD spectrum. Compounds 1–3 possessed significantantimicrobial activity against Escherichia coli 1.044,Staphylococcus aureus 1.252, and Bacillus subtilis 1.079. Moreover, compounds 1–3 showed obvious inhibitoryeffects on mouse spleen cell proliferation with successiveIC50 values of 0.52, 0.19, and 0.24 lM.