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Open access

Jian-Bin Hu, Qiong Li and Jing Li

ISSR Analysis of Somaclonal Variation in Callus-Derived Plants of Amorphophallus Rivieri Durieu

This communication reports detection of somaclonal variation among tissue culture-raised plants of Amorphophallus rivieri Durieu, an economically important crop in China, with high content of glucomannan in its corms. A population of regenerated plants was obtained from a single donor plant of A. rivieri via corm organogenesis, and 28 plants were randomly selected as a representative sample and subjected to analysis of somaclonal variation using inter-simple sequence repeat (ISSR) markers. Of the 26 ISSR primers screened, 13 gave distinct and reproducible band patterns, yielding 131 bands with an average of 10.1 bands per primer. Ten primers were polymorphic and generated 16 polymorphic bands with 12.2% mean polymorphism. Based on the ISSR data from the regenerated plants and the donor plant, Jaccard's similarity coefficients were calculated; they ranged from 0.961 to 1.000 with a mean of 0.982. A dendrogram was constructed using the unweighted pair group method with arithmetic mean (Upgma); it showed that a majority of regenerated plants (including the donor plant) clustered closely, with a mean similarity coefficient of 0.987. Low somaclonal variation observed in the regenerated plants indicates that rapid propagation of A. rivieri via corm organogenesis is a practicable method with a low risk of genetic instability.

Open access

Wei-Han Chang, Jing-Jing Yan, Xin Li, Hai-Yan Guo and Yu Liu

Abstract

Background: Cardiomyocyte hypertrophy is a common complication of hypertension, and is recognized as an important risk factor for cardiovascular diseases. Up to now, no study has been made on the effects of telmisartan on Ang II-induced cardiomyocyte hypertrophy.

Objective: Investigate the effects of telmisartan on angiotensin II-induced cardiomyocyte hypertrophy and the phosphorylation of extracellular signal-regulated kinase (p-ERK1/2) in rat-cultured cardiomyocytes.

Methods: Rat myocardial cells were cultured. Beating rates of the cardiomyocytes, cell volumes, total protein contents, protein synthesis rates, and ERK activity were measured. The phosphorylation of p-ERK1/2 was analyzed by Western blot.

Results: Treatment of cultured cardiomyocytes with telmisartan inhibited angiotensin II-induced increases in cell volume, beating rate, total protein content and protein synthesis rate. Telmisartan markedly inhibited p-ERK1/2 phosphorylation in a dose- and time-dependent manner.

Conclusion: Telmisartan could suppress cardiomyocyte hypertrophy induced by angiotensin II. The mechanism might be related to the inhibition of p-ERK1/2 phosphorylation.

Open access

Jianshe Yang, Wenjian Li, Xigang Jing, Zhuanzi Wang and Qingxiang Gao

A method on theoretical simulation of chromosome breaks in cells exposed to heavy ions

Background. The aim of this study is to assess an easy and quick method on simulating chromosome breaks in cells exposed to heavy charged particles.

Methods. The theoretical value of chromosome break was calculated, and the validated comparison with the experimental value by using a premature chromosome condensation technique was done.

Results. A good consistence was found to be appeared between the theoretical and experimental value.

Conclusions. This suggested that a higher relative biological effectiveness of heavy ions was closely correlated with its physical characteristics and besides, a safe approach on predicting chromosome breaks in cells exposed to heavy ions at off-line environment come to be considered. Furthermore, three key factors influencing the theoretical simulation was investigated and discussed.

Open access

Jun-Bao Li, Jing Liu, Jeng-Shyang Pan and Hongxun Yao

Abstract

Magnetic Resonance Super-resolution Imaging Measurement (MRIM) is an effective way of measuring materials. MRIM has wide applications in physics, chemistry, biology, geology, medical and material science, especially in medical diagnosis. It is feasible to improve the resolution of MR imaging through increasing radiation intensity, but the high radiation intensity and the longtime of magnetic field harm the human body. Thus, in the practical applications the resolution of hardware imaging reaches the limitation of resolution. Software-based super-resolution technology is effective to improve the resolution of image. This work proposes a framework of dictionary-optimized sparse learning based MR super-resolution method. The framework is to solve the problem of sample selection for dictionary learning of sparse reconstruction. The textural complexity-based image quality representation is proposed to choose the optimal samples for dictionary learning. Comprehensive experiments show that the dictionary-optimized sparse learning improves the performance of sparse representation.

Open access

Ma Ying, Li Jing, Yu Guansheng and Yuan Dongyang

Abstract

In this paper, we use China’s 1986-2008 data to make an empirical analysis on the interrelationship between trade openness, economic growth and the structural change of labor-intensive industries by using simultaneous equation models and a VAR model. Our empirical study leads to the three conclusions. First, trade openness has accelerated economic growth, though with some negative impact on the development of labor-intensive industries; Second, economic growth has had a positive effect on trade openness, but again negatively impacted the development of labor-intensive industries. Third, the expansion of labor-intensive industries has had negative effects on both trade openness and economic growth.

Methodologically we rely on the transformation theory of industrial structure as an analytical framework to empirically study these three paradoxical outcomes. We introduce the three variables: trade openness, economic growth and the change of labor-intensive industries, as dependent as well as independent variables into our empirical models. And then we use technological progress, the share of secondary industries to GDP, total employment and investment ratio as control variables in order to test the robustness of the empirical results. In addition to explaining the factors responsible for changes in labor-intensive export industries we also provide two policy implications: First, labor-intensive industries should be scaled down to improve the efficiency of resources allocation. Second, China should timely transform its industrial structure of the export sectors from the one that is dominated by labor-intensive industries to the one that is dominated by capital (technology)-intensive industries so as to induce the export sectors to move in the direction favorable to the transformation of China’s present outward pattern of economic development.

Open access

Wu Yan and Fu Jing-Li

Abstract

This paper deals with the Noether’s theory for variable mass system on time scales. The calculus on time scales unifies and extends variable mass system continuous model and discrete model into a single theory. Firstly, Hamilton’s principle of the variable mass system on time scales is given. Secondly, based on the quasi-invariance of the Hamilton’s action under a group of infinitesimal transformations, Noether’s theorem and its inverse theorem of the variable mass system on time scales are presented. Finally, two examples are given to illustrate the applications of the results.

Open access

Sheng-nan Gong and Jing-li Fu

Abstract

This paper propose Noether symmetries and the conserved quantities of the relative motion systems on time scales. The Lagrange equations with delta derivatives on time scales are presented for the system. Based upon the invariance of Hamilton action on time scales, under the infinitesimal transformations with respect to the time and generalized coordinates, the Hamilton’s principle, the Noether theorems and conservation quantities are given for the systems on time scales. Lastly, an example is given to show the application the conclusion.

Open access

Zhenghua Li, Yi Hong, Jing Zhang and Xiang Li

Abstract

In this work, a signal transformation method to quantitatively analyze fine magnetic structures in nanometer length scales measured by magnetic force microscopy has been developed. Nanosized magnetic domains, magnetic charges with reconstructed polarity as well as quantified magnetic field contours of samples (such as ordered FePt dot arrays, hard magnetic thin films and polycrystalline La0.7Sr0.3 MnO3 (LSMO) films ) were investigated based on the basic principles of deconvolution and micromagnetics. The present technique is crucial for the analysis of fine magnetic structures, and is important for the development of next generation magnetic recording industry.

Open access

Hao Luo, Tingting Liu, Jun Ma, Wei Wang, Heng Li, Pengwei Wang, Jintao Bai and Guangyin Jing

Abstract

The morphology of nanospheres is crucial for designing the nanofabrication in the nanosphere lithography. Here, by plasma etching, the controllable tailoring of the nanosphere is realized and its morphology dependence on the initial shape, microscopic roughness, and the etching conditions is investigated quantitatively. The results show that the shape evolution strongly depends on the etching gas, power, and process duration. Particularly, the aspect ratio (diameter/height) significantly increases with violent etching, turning the spherical shape into tiny ellipsoidal nanoparticles. The findings are practical to the protocol of non-uniform etching of nanoobjects and provide the useful design tool for the device fabrication at nanoscale.