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  • Author: Z. Yang x
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Open access

D. Zhang, Z. Zhang and K. Yang

Abstract

Embryonic root (radicle) development in the mature embryo following germination is essential for the formation of the root organ in plants. In this study a phenotype described by a lack of proper radicle development was identified in an intraspecific hybrid of Populus tomentosa Carr.. Association of this trait with Amplified Fragment Length Polymorphisms (AFLPs) markers was investigated in a segregating F1 population generated by intraspecific-controlled crossing between a highly fertile female P. tomentosa clone “5082” and a male P. tomentosa clone “JY”. A total of 3193 seeds were obtained, and the rate of germination found to be 48.74% at 15 to 20 days. 376 (24%) of seedlings were shown to lack a root organ following visual assessment of the developing radicle. Genetic regulation of this trait appeared to be via a single dominant gene or a set of tightly linked genes, based on the 3:1 ratio of the rooting versus nonrooting seed embryos. A Bulked Segregant Analysis approach using 5600 AFLP markers was applied to this population and revealed 2 AFLP markers, EcoRI + GAG/ Mse I + AAT-492 and EcoRI + GAG/Mse I + CCA-502, that were associated with the radicle development-controlling locus in P. tomentosa. The AFLP markers identified have potential for application in hybrid breeding via marker assisted selection, and provide a starting point for map based cloning of the radical development-controlling gene.

Open access

Joe-Ming Yang, Zen-Wei Yang and Chien-Ming Tseng

ABSTRACT

In this study, numerical analysis was carried out by using the finite element method to construct the first mode shape of damaged stiffened plates, and the damage locations were detected with two-dimensional discrete wavelet analysis. In the experimental analysis, four different damaged stiffened structures were observed. Firstly, each damaged structure was hit with a shaker, and then accelerometers were used to measure the vibration responses. Secondly, the first mode shape of each structure was obtained by using the wavelet packet, and the location of cracks were also determined by two-dimensional discrete wavelet analysis. The results of the numerical analysis and experimental investigation reveal that the proposed method is applicable to detect single crack or multi-cracks of a stiffened structure. The experimental results also show that fewer measurement points are required with the proposed technique in comparison to those presented in previous studies.

Open access

X. Sun, Z. Xue, S. Han, L. Chen, X. Xu and Z. Yang

Abstract

Due to the separation of magnetic field, electrical isolation and thermal isolation, motor drives possess a high fault-tolerance characteristic. In this paper, comparative study of mutual inductance between the proposed segmented rotor switched reluctance motor (SSRM) and the conventional switched reluctance motor (SRM) is carried out first, illustrating that the proposed SSRM has less mutual inductance between phases than the conventional SRM. In addition, if winding faults or power converter faults lead to phase failure, a comparative analysis on fault-tolerant performance under phase failure condition between the proposed SSRM and the conventional SRM is simulated in detail using the finite element method (FEM). Simulation results reveal that dynamic performance of the proposed SSRM, including output torque and phase current, is better than that of the conventional SRM. That is, the capacity of operating with the fault under phase failure condition in the proposed SSRM is superior to that in the conventional SRM.

Open access

Liu Bin, Meng Zhang, Liu Lixia, Zang Aimin, Yang Hua, Shang Yanhong, Yang Yang, Gao Feng, Liu Bo, Zhang Yonggang and Tian Huiping

Abstract

Background: MiRNA-30c was a tumor suppressor in several human cancers, however, its association with clinicopathological features and prognosis in colorectal cancer (CRC) is unclear.

Materials and Methods: The expression level of miRNA-30c in 192 pairs of colorectal cancer and adjacent normal tissues was detected by Quantitative RT-PCR, the association between miRNA-30c expression and clinical characteristics and prognosis were statistically analyzed.

Results: miRNA-30c was significantly lower in CRC tissues specimens compared with matched normal adjacent tissue (P<0.001). MiRNA-30c was positively correlated with tumor size (P=0.012), TMN stage (P=0.002) and lymph node metastasis (P=0.004). The univariate analysis showed CRC patients with low miRNA-30c had distinctly shorter overall survival (P<0.001) than patients with high miRNA-30c expression level. The multivariate analysis was performed and informed that low miRNA-30c expression (P<0.001) might be an independent prognostic predictor for poor prognosis.

Conclusion: miRNA-30c could predict the prognosis of colorectal cancer which is helpful to choose reasonable treatment measures.

Open access

J. H. Gu, Z. Lu, L. Long, Z. Y. Zhong, C. Y. Yang and J. Hou

Abstract

Highly conductive gallium-doped zinc oxide (GZO) transparent thin films were deposited on glass substrates by RF mag­netron sputtering. The deposited films were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), four-point probe and UV-Vis spectrophotometer, respectively. The effect of growth temperature on the structure and optoelectrical properties of the films was investigated. The results demonstrate that high quality GZO films oriented with their crystal­lographic c-axis perpendicular to the substrates are obtained. The structure and optoelectrical properties of the films are highly dependent on the growth temperature. It is found that with increasing growth temperature, the average visible transmittance of the deposited films is enhanced and the residual stress in the thin films is obviously relaxed. The GZO films deposited at the growth temperature of 400°C, which have the largest grain size (74.3 nm), the lowest electrical resistivity (1.31×10-3 Ω·cm) and the maximum figure of merit (1.46×1O-2Ω-1), exhibit the best optoelectrical properties. Furthermore, the optical proper­ties of the deposited films were determined by the optical characterization methods and the optical energy-gaps were evaluated by extrapolation method. A blue shift of the optical energy gap is observed with an increase in the growth temperature.

Open access

X. Sun, B. Su, L. Chen, Z. Yang and K. Li

Abstract

In this paper, a new type of interior composite-rotor bearingless permanent magnet synchronous motors (BPMSMs) with two layer permanent magnets (PMs) is proposed. In order to reduce the torque ripple of this kind of motors, the sizes of PMs are optimized. Moreover, the magnetic field analysis of the interior composite-rotor BPMSM with two layer PMs is carried out by the finite element method (FEM). The corresponding static electronic magnetic characteristics at no load, including magnetic field, PM flux linkage and inductance, are studied in detail. In addition, electromagnetic torque characteristics and suspension force characteristics are also investigated thoroughly. The results of the analysis and simulation lay a significant foundation for further research on the interior composite-rotor BPMSMs with two layer PMs.

Open access

L. Hu, X.Y. Lin, Z.X. Yang, X.P. Yao, G.L. Li, S.Z. Peng and Y. Wang

Abstract

In this assay, we developed and evaluated a multiplex PCR (mPCR) for its ability in detecting multiple infections of swine simultaneously. Four pairs of primers were used to detect five viruses. Specific primers were designed for classical swine fever virus (CSFV), African swine fever virus (ASFV) and pseudorabies (PRV). A pair of primers was designed prudently for two different types of porcine reproductive and respiratory syndrome virus that respectively were porcine reproductive and respiratory syndrome virus (PRRSV), highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV). The detection limits of the mPCR were 1.09×104, 1.50×103, 2.10×103, 1.30×103 and 8.97×102 copies/reaction for CSFV, ASFV, HP-PRRSV, PRRSV and PRV, respectively. A total of 49 clinical specimens were tested by the mPCR, and the result showed that co-infection by two or three viruses was 51%. In conclusion, the PCR is a useful tool for clinical diagnosis of not only single infections but also mixed infections in swines.

Open access

X. F. Yang, Z. Y. Jiang, Z. M. Tian, Y. Q. Qiu, L. Wang, K. G. Gao, Y. J. Hu and X. Y. Ma

Abstract

The uneven development of adipose tissues reflects a differential occurrence of biological events in vivo while the underlying molecular mechanism remains largely unknown. In the present study, the in vivo inflammatory status of an inbred obese porcine model, Lantang pig, was assessed, aiming to provide evidence for obesity biology. Compared with genetically lean pigs (crossbred, Duroc × Landrace × Large White), Lantang pigs exhibited a larger amount of ultra large adipocytes in subcutaneous adipose tissue accompanied with higher expression of macrophage/monocytes markers and pro-inflammatory genes (TLR4, CD14, CD11β, MCP1, TNFα, IL1β and IL6) and lower expression of cellular antioxidant enzymes (SOD1, 2 and 3). Plasma concentrations of LPS and TNF-α were also higher in Lantang pigs than in lean pigs. Among adipose tissues of Lantang pigs, the subcutaneous tissue had the most abundant expression of inflammation related genes (TLR4, CD14, TNFα and IL6) and the lowest level of cellular antioxidant genes (SOD 1 and 2), while the perirenal adipose tissue had opposite profile. Significant activation of p38 MAPK pathway was indicated by increased phosphorylation of p38 in the subcutaneous adipose tissue of Lantang pigs. Collectively, the bacteria-derived LPS induced inflammation-associated oxidative stress indeed exists in adipose tissues of Lantang pig, and the differential expressions of inflammatory and antioxidant genes, to some extent, account for the uneven development of the adipose tissue within bodies.

Open access

W. Yang, H. Xiu, Y. Xiong, J. Wang, C. Yuan, J. Wei and Z. Zhou

Abstract

(Na0.52K0.44Li0.04)0.97La0.01Ta0.20Nb0.80O3 (KNLTN-La0.01) lead-free subtransparent ceramics was prepared by a conventional sintering technique. The structure and the optical properties of the ceramics were investigated. The room temperature crystallographic indexing revealed the ABO3 perovskite type, tetragonal phase and P4mm point group in the ceramics. The surface and fractured surface SEM micrographs showed a dense microstructure with few micropores in KNLTN-La0.01 ceramics, which was obviously better than for the pure KNLTN ceramics. The refractive indexes of the films were investigated by an ellipsometer and the results show that the KNLTN-La0.01 subtransparent ceramics reveals significant wavelength dependent dispersion. The refractive index ranges from 2.14 to 2.06 with the wavelength increase from 380 nm to 900 nm. The dispersive behavior was analyzed by three parameters of Cauchy dispersion model and the values of the parameters A, B and C are 2.0610±0.0005, 0.0054±0.0003 and 0.00069±0.00004, respectively.

Open access

Z. S. Kim, J. W. Hwang, S. W. Lee, C. Yang and P. G. Gorovoy

Abstract

We studied and compared genetic variation of Korean pine (Pinus koraiensis Sieb. et Zucc.) from 12 natural populations in Korea, China, and Russian Far East using allozymes and random amplified polymorphic DNAs (RAPDs). Eighteen polymorphic allozyme loci and 38 polymorphic RAPD fragments were analyzed. The level of allozyme diversity (A = 1.95, P95 = 46.8%, Ho = 0.158, He = 0.169) and the degree of genetic differentiation (FST = 0.069) were comparable to those of other pines with similar life histories and ecological traits. Allozyme (He) as well as RAPD (Shannon’s index) variation decreased from south (Korea) to north (Russia), providing an evidence for the hypothesis of Korean pine’s northward migration. Differentiations among three different regions (Korea, China, and Russia) as well as among populations within regions were small. Substantial gene flow (Nm = 3.4) may be a partial explanation to this result. Clustering algorithms using various genetic distance measures showed some decisive geographic patterns at allozyme and RAPD level: the geographically close populations tended to be clustered together. On the other hand, two Chinese populations, Xobukho and Wangging, were grouped with the Russian populations rather than with the other Chinese populations. The Xiaoxing’anling and other mountains extended from north to south seemed to function as a barrier against gene flow between the Xobukho and Wangging (located east of the mountains) and the other Chinese P. koraiensis populations (located west of the mountains). The genetic diversities and differentiation estimated from RAPD data in Korean pine were congruent with those of allozymes.