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  • Author: Jing Li x
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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.

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.

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.

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.

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.

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.

Abstract

In order to meet the diverse and multilevel health service needs of the people, following the implementation of the “multi-point practice” of registered physicians by the government in 2009, many pilot projects on the legality of “shared nurses” have been carried out, but there are many difficulties in the process. Through reviewing and researching the relevant literature inland and abroad, this study explores the application of family-community-hospital integrated medical and nursing management model in order to provide a reference for the development and management of “shared nurses” in China.

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.

Abstract

Glasses composed of ternary components (35 – x)Sb2O3–xBi2O3–65P2O5 (0 ⩽ x ⩽ 20 mol%) have been prepared and investigated as a potential alternative to lead-free glass for low temperature applications. Their structural properties were studied by Infrared Spectroscopy IR and Differential Thermal Analysis DTA. Results from the IR showed that Sb3+ and Bi3+ were responsible for glass network structure, which was supported by the diversification of density ρ and molar volume Vm with an increasing amount of Bi2O3. Glass transition temperature Tg, thermal stability, and coefficient of thermal expansion increased after substitution of Bi2O3 for Sb2O3 within the range of 0 mol% to 20 mol%. The water durability decreased and then increased; it could be attributed to the corrosion resistant P–O–Sb bonds. A typical sample of 25Sb2O3–10Bi2O3–65P2O5 possesses excellent properties and can be a promising candidate for further applications.

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.