Estimation of main cable tension force of suspension bridges based on ambient vibration frequency measurements

Jun Wang,Weiqing Liu,Lu Wang,Xiaojian Han 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.56 No.6

In this paper, a new approach based on the continuum model is proposed to estimate the main cable tension force of suspension bridges from measured natural frequencies. This approach considered the vertical vibration of a main cable hinged at both towers and supported by an elastic girder and hangers along its entire length. The equation reflected the relationship between vibration frequency and horizontal tension force of a main cable was derived. To avoid to generate the additional cable tension force by sagextensibility, the analytical solution of characteristic equation for anti-symmetrical vibration mode of the main cable was calculated. Then, the estimation of main cable tension force was carried out by antisymmetric characteristic frequency vector. The errors of estimation due to characteristic frequency deviations were investigated through numerical analysis of the main cable of Taizhou Bridge. A field experiment was conducted to verify the proposed approach. Through measuring and analyzing the responses of a main cable of Taizhou Bridge under ambient excitation, the horizontal tension force of the main cable was identified from the first three odd frequencies. It is shown that the estimated results agree well with the designed values. The proposed approach can be used to conduct the long-term health monitoring of suspension bridges.

Morphological, Physiological and Biochemical Responses of Gerbera Cultivars to Heat Stress

Chen, Wen,Zhu, Xiaoyun,Han, Weiqing,Wu, Zheng,Lai, Qixian Korean Society of Horticultural Science 2016 원예과학기술지 Vol.34 No.1

Heat stress is an agricultural problem for Gerbera jamesonii, and it often causes poor seedling growth, reduced flower yield and undesirable ornamental characteristics of flowers. However, little is known about the effect of heat stress on the morphological, physiological and biochemical characteristics of gerbera plants. Here, the responses of six cultivars of Gerbera jamesonii to heat stress were investigated. Under a 1-d heat treatment at $45^{\circ}C$, the leaves of gerbera cultivars showed yellowing, wilting, drying and death to varying degrees. The heat treatment also resulted in increased electrical conductivity, decreased soluble protein and chlorophyll contents, and the accumulation of malondialdehyde (MDA) and proline in leaves. Moreover, heat tolerance differed among the six tested gerbera cultivars. Our results demonstrated that among the six gerbera cultivars, 'Meihongheixin' is a heat-resistant cultivar, whereas 'Beijixing' is a heat-sensitive one. 'Shijihong' and 'Linglong' are relatively heat-resistant cultivars, and 'Dadifen' and 'Taiyangfengbao' are relatively heat sensitive.

Morphological, Physiological and Biochemical Responses of Gerbera Cultivars to Heat Stress

Wen Chen,Xiaoyun Zhu,Weiqing Han,Zheng Wu,Qixian Lai 한국원예학회 2016 원예과학기술지 Vol.34 No.1

Heat stress is an agricultural problem for Gerbera jamesonii, and it often causes poor seedling growth, reduced flower yield and undesirable ornamental characteristics of flowers. However, little is known about the effect of heat stress on the morphological, physiological and biochemical characteristics of gerbera plants. Here, the responses of six cultivars of Gerbera jamesonii to heat stress were investigated. Under a 1-d heat treatment at 45°C, the leaves of gerbera cultivars showed yellowing, wilting, drying and death to varying degrees. The heat treatment also resulted in increased electrical conductivity, decreased soluble protein and chlorophyll contents, and the accumulation of malondialdehyde (MDA) and proline in leaves. Moreover, heat tolerance differed among the six tested gerbera cultivars. Our results demonstrated that among the six gerbera cultivars, ‘Meihongheixin’ is a heat-resistant cultivar, whereas ‘Beijixing’ is a heatsensitive one. ‘Shijihong’ and ‘Linglong’ are relatively heat-resistant cultivars, and ‘Dadifen’ and ‘Taiyangfengbao’ are relatively heat sensitive.

Genetic Characterization of the Escherichia coli O66 Antigen and Functional Identification of its wzy Gene

Cheng, Jiansong,Liu, Bin,Bastin David A.,Han, Weiqing,Wang, Lei,Feng Lu The Microbiological Society of Korea 2007 The journal of microbiology Vol.45 No.1

Escherichia coli is a clonal species, and occurs as both commensal and pathogenic strains, which are normally classified on the basis of their O, H, and K antigens. The O-antigen (O-specific polysaccharide), which consists of a series of oligosaccharide (O-unit) repeats, contributes major antigenic variability to the cell surface. The O-antigen gene cluster of E. coli O66 was sequenced in this study. The genes putatively responsible for the biosynthesis of dTDP-6-deoxy-L-talose and GDP-mannose, as well as those responsible for the transfer of sugars and for O-unit processing were identified based on their homology. The function of the wzy gene was confirmed by the results of a mutation test. Genes specific for E. coli O66 were identified via PCR screening against representatives of 186 E. coli and Shigella O type strains. The comparison of intergenic sequences located between galF and the O-antigen gene cluster in a range of E. coli and Shigella showed that this region may perform an important function in the homologous recombination of the O-antigen gene clusters.

Genetic Characterization of the Escherichia coli O66 Antigen and Functional Identification of its wzy Gene

Jiansong Cheng,Bin Liu,David A. Bastin,Weiqing Han,Lei Wang,Lu Feng 한국미생물학회 2007 The journal of microbiology Vol.45 No.1

Escherichia coli is a clonal species, and occurs as both commensal and pathogenic strains, which are normally classified on the basis of their O, H, and K antigens. The O-antigen (O-specific polysaccharide), which consists of a series of oligosaccharide (O-unit) repeats, contributes major antigenic variability to the cell surface. The O-antigen gene cluster of E. coli O66 was sequenced in this study. The genes putatively responsible for the biosynthesis of dTDP-6-deoxy-L-talose and GDP-mannose, as well as those responsible for the transfer of sugars and for O-unit processing were identified based on their homology. The function of the wzy gene was confirmed by the results of a mutation test. Genes specific for E. coli O66 were identified via PCR screening against representatives of 186 E. coli and Shigella O type strains. The comparison of intergenic sequences located between galF and the O-antigen gene cluster in a range of E. coli and Shigella showed that this region may perform an important function in the homologous recombination of the O-antigen gene clusters.

Endothelial-specific deletion of Ets-1 attenuates Angiotensin II-induced cardiac fibrosis via suppression of endothelial-to-mesenchymal transition

( Lian Xu ),( Mengxia Fu ),( Dongrui Chen ),( Weiqing Han ),( Michael C. Ostrowski ),( Paul Grossfeld ),( Pingjin Gao ),( Maoqing Ye ) 생화학분자생물학회 2019 BMB Reports Vol.52 No.10

Cardiac fibrosis is a common feature in chronic hypertension patients with advanced heart failure, and endothelial-tomesenchymal transition (EndMT) is known to promote Angiotensin II (Ang II)-mediated cardiac fibrosis. Previous studies have suggested a potential role for the transcription factor, ETS-1, in Ang II-mediated cardiac remodeling, however the mechanism are not well defined. In this study, we found that mice with endothelial Ets-1 deletion showed reduced cardiac fibrosis and hypertrophy following Ang II infusion. The reduced cardiac fibrosis was accompanied by decreased expression of fibrotic matrix genes, reduced EndMT with decreased Snail, Slug, Twist, and ZEB1 expression, as well as reduced cardiac hypertrophy and expression of hypertrophy-associated genes was observed. In vitro studies using cultured H5V cells further confirmed that ETS-1 knockdown inhibited TGF- β1-induced EndMT. This study revealed that deletion of endothelial Ets-1 attenuated Ang II-induced cardiac fibrosis via inhibition of EndMT, indicating an important ETS-1 function in mediating EndMT. Inhibition of ETS-1 could be a potential therapeutic strategy for treatment of heart failure secondary to chronic hypertension. [BMB Reports 2019; 52(10): 595-600]