Wyniki wyszukiwania - Biblioteka Nauki

1

Mixed Pseudo-orthogonal Frequency Coding for SAW RFID Tags

100%

Xu M. , Xiao X. , Yuan Q. , Zong Y.

Archives of Acoustics

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2018

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tom Vol. 43, No. 4

681--687

EN

A mixed pseudo-orthogonal frequency coding (Mixed-POFC) structure is proposed as a new spreadspectrum technique in this paper, which employs frequency and time diversity to enhance tag properties and balances the spectrum utilization and code diversity. The coding method of SAW RFID tags in this paper uses Mixed-POFC with multi-track chip arrangements. The cross-correlation and auto correlation of Mixed-POFC and POFC are calculated to demonstrate the reduced overlap between the adjacent center frequencies with the Mixed-POFC method. The center frequency of the IDT and Bragg reflectors is calculated by a coupling of modes (COM) module. The combination of the calculation results of the Bragg reflectors shows that compared with a 7-chip POFC, the coding number of a 7-chip Mixed-POFC is increased from 120 to 144 with the same fractional bandwidth of 12%. To demonstrate the validity of Mixed-POFC, finite element analysis (FEA) technology is used to analyze the frequency characteristics of Mixed-POFC chips. The maximum error between designed frequencies and simulation frequencies is only 1.7%, which verifies that the Mixed-POFC method is feasible.

2

The influence of landing mat composition on ankle injury risk during a gymnastic landing: a biomechanical quantification

88%

Xiao X. , Xiao W. , Li X. , Wan B. , Shan G.

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tom Vol. 19, no. 1

105--113

EN

Purpose: About 70% injury of gymnasts happened during landing – an interaction between gymnast and landing mat. The most injured joint is the ankle. The current study examined the effect of mechanical properties of landing mat on ankle loading with aims to identify means of decreasing the risk of ankle injury. Method: Gymnastic skill – salto backward stretched with 3/2 twist was captured by two high-speed camcorders and digitized by using SIMI-Motion software. A subject-specific, 14-segment rigid-body model and a mechanical landing-mat model were built using BRG.LifeMODTM. The landings were simulated with varied landing-mat mechanical properties (i.e., stiffness, dampness and friction coefficients). Result: Real landing performance could be accurately reproduced by the model. The simulations revealed that the ankle angle was relatively sensitive to stiffness and dampness of the landing mat, the ankle loading rate increased 26% when the stiffness was increased by 30%, and the changing of dampness had notable effect on horizontal ground reaction force and foot velocity. Further, the peak joint-reaction force and joint torque were more sensitive to friction than to stiffness and dampness of landing mat. Finally, ankle muscles would dissipate about twice energy (189%) when the friction was increased by 30%. Conclusion: Loads to ankles during landing would increase as the stiffness and dampness of the landing mat increase. Yet, increasing friction would cause a substantial rise of the ankle internal loads. As such, the friction should be a key factor influencing the risk of injury. Unfortunately, this key factor has rarely attracted attention in practice.

3

Systematic assessment of reference genes for RT-qPCR across plant species under salt stress and drought stress

75%

Xiao X. , Wu X. , Ma J. , Li P. , Li T. , Yao Y.

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tom 37

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nr 09

EN

Suitable reference gene (RGs) is the prerequisite for accurate normalization of real-time quantitative PCR (RT-qPCR) data. However, previous results are diverse in various researches that focused on selecting stable RGs. This study aims at systematically assessing various RGs in plants under salt stress or drought stress by collection of geNorm rankings of genes, data transformation and statistic analysis. Although none of the analyzed genes can guarantee universally stable expressions in plant species under salt stress or drought stress, we found that 18S (18S ribosomal RNA) was generally the least stable gene under salt and drought stress. This gene should not be used as the RG in RT-qPCR. On the contrary, it is least risk to use EF1 for salt stress and TIP41 for drought treatment experiments. We compared the effects of salt and drought stresses on 7 frequently used RGs through paired-samples T test. The expression of Ubiquitin gene under drought stress is much more unstable than that under salt stress. The tested genes belonging to multigene family and having different stability could be one reason of variations in the published studies, which was supported by the analysis of expression profile of Salicornia europaea transcriptome. This is the first systematic assessment quantifying global stability of Rgs across plant species under salt stress and drought stress, which will improve our understanding of RGs and facilitate the future work on RGs selection.

4

Identification of novel pathways in pathogenesis of ketosis in dairy cows via iTRAQ/MS

63%

Shu S. , Xu C. , Xia C. , Xiao X. , Wang G. , Fan Z. , Cao Y. , Wang Y. , Zhang H.

Journal of Veterinary Research

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2016

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tom 60

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nr 3

5

Large-scale de novo transcriptome analysis reveals specific gene expression and novel simple sequence repeats markers in salinized roots of the euhalophyte Salicornia europaea

51%

Ma J. , Xiao X. , Li L. , Maggio A. , Zhang D. , Mohamad O. A. A. , Oosten M. V. , Huang G. , Sun Y. , Tian C. , Yao Y.

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nr 08