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  • Author: Jian-jun Yang x
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Open access

Li Hua-Wu, Ma Hong-Xing, Jiang Jian-Feng, Yang Xi-Jun and Yang Xing-Hua

Abstract

With the continuous increase of output power ratings, multi-phase (multichannel) interleaved power factor corrector (IPFC) is gradually employed in domestic and commercial inverter air-conditioners. IPFC can solve several main problems, such as power rating increase, power device selection, input current ripple reduction as well as inductor on-board mounting. But for a multi-phase IPFC, the key problem is that it should show rapid dynamic responds and good current sharing capability, so in this paper the aim is to improve the dynamic performance and current sharing capability by means of passivity control theory. Considering the power circuit topology of a four-phase IPFC, an EL (Euler-Lagrange) mathematical model is established when the IPFC operates in continuous conduction mode (CCM). Then the passivity of the four-phase IPFC is proved, and the passivity-based controller using the state variables feedback and damping injection method is designed. The proposed control scheme, which is easy to control and needs no proportion integral controller, has strong robustness on disturbance from singlephase AC input voltage, the load as well as the parameters of the employed devices. Even in wide-range load condition, the mains current has a fast dynamic response and the average output voltage almost keep unchanged. As a result, the main functions of the four-phase IPFC are implemented including nearly unitary power factor and constant DC output voltage. Meanwhile, the four-phase IPFC acquires an excellent current sharing effect after using passivity-based controller. The above analysis has been proved with simulated results by means of MATLAB/SIMULINK and experimental results, showing that the passivity-based IPFC controller has superior performances and feasibility.

Open access

Xiu-lan Zou, Jun Yang, Jian-ming Yang, Yan-qun Liu, Wen Wang, Jun Zheng, Bao-hua Ma and Fang-yuan Chen

Abstract

Background: Diabetic cardiomyopathy is an important complication of type 2 diabetics. The role of immunoinflammation, immunity, and diet has not been adequately clarified.

Objective: We investigated the relationships between diabetic cardiomyopathy and immuno-inflammation, as well as immunity and diets.

Methods: Sixty Sprague-Dawley (SD) male rats were included in this study, from which 12 were randomly selected as the normal control group (group A) and of which the remaining 48 were considered as the type 2 diabetes mellitus (T2DM) model group. Group A was fed with common diets and the T2DM model group, with high-glucose diets (by adding 20% cane sugar, 10% lard, and 2.5% cholesterol into a 67.5% common diet). After 4-week feeding, the T2DM model group was randomly allocated into three groups according to the diet, highfat diet group (group B), common diet group (group C), and low-fat diet group (group D). All the three groups were then fed for another 10 weeks. At the end of the experiment, body weight, random blood glucose levels, and cardiac weight were measured. Left ventricular tissue was obtained for light microscopy and electron microscopy. Deposits of immunoglobulin G (IgG) in myocardium were identified by immunohistochemistry. Serum levels of high-sensitivity C-reactive protein (hs-CRP) were determined using the enzyme-linked immunosorbent assay (ELISA). All data were statistically analyzed.

Results: The serum level of hs-CRP was significantly higher in groups B, C, and D, than in the control group. Therefore, IgG deposits among cardiac muscle cells were observed in all the model groups, significant deviations were noted in group A (p <0.01) and IgG deposits were less in group D than in groups B and C (p <0.01).

Conclusion: Immuno-inflammation participates in the development of T2DM and diabetic cardimyopathy. Immune injury can be alleviated following dietary interference.

Open access

Yi-Xuan Hou, Chun Xie, Kang Wang, Yu-Ting Zhao, Yang-Yang Xie, Hong-Yan Shi, Jian-Fei Chen, Li Feng, Guang-Zhi Tong, Xiu-Guo Hua, Cong-Li Yuan, Yan-Jun Zhou and Zhi-Biao Yang

Abstract

Introduction: A real-time RT-PCR method for identification and quantification of porcine epidemic diarrhoea virus (PEDV) strains in China was developed.

Material and Methods: Based on the conserved sequence of the PEDV nucleocapsid (N) gene, a primer pair and probe were designed to establish a TaqMan-MGB real-time RT-PCR assay for quantitative detection of the virus. The sequence was cloned into the pMD18-T vector and a series of diluted recombinant plasmids were used to generate a standard curve with an R2 value of 0.999.

Results: The developed quantitative PCR assay detected viral titres as low as 0.1 TCID50 with high specificity and no cross-reaction with other porcine viruses (PoRV, TGEV, PRRSV, or CSFV). The intra-batch and inter-batch coefficients of variation were both less than 1%, which indicated good reproducibility. Thirty clinical diarrhoea samples obtained from pigs in Shanghai and Fujian were analysed using this quantitative PCR assay. Out of these samples, 93.3% were found to be PEDV positive.

Conclusion: This approach is suitable for clinical sample identification and pathogenesis studies.

Open access

Wen-jie Zhang, Zhao-xia Li, Deng-hai Mi, Jing Li, Jian-jun Yang, Wei-wu Mao, Yan-xuan Gong and Yan Qu

Abstract

Objective To investigate the occurrence of basal core promoter (BCP) and pre-C mutations in patients with hepatitis B virus (HBV) infection in Gansu Province, China, and to analyze the correlation of HBV mutation and HBV genotype with primary hepatocellular carcinoma (HCC).

Methods PCR-RFLP was applied to detect HBV subgenotypes, and the presence of the pre-C and BCP mutations in 62 patients with HCC, 70 patients with hepatitis B induced liver cirrhosis (LC) and 90 patients with chronic hepatitis B (CHB).

Results In HCC patients, genotype C was the major genotype (70.97%). The pre-C mutation was found in 59.68%, 31.43% and 16.67% patients with HCC, LC and CHB, respectively. The frequency of BCP mutations was significantly different between patients with HCC, LC and CHB (74.19%, 51.43% and 37.78%, respectively; X2=30.727, 19.540, respectively, P < 0.01). Patients in HCC group had a higher incidence of pre-C as well as BCP mutations compared to the other groups. The prevalence of pre-C and BCP mutations was significantly higher in patients with genotype C1 (44.32% and 69.32%, respectively) compared to patients with other subgenotypes (P < 0.05).

Conclusions The incidence of pre-C and BCP mutations increases with disease progression. Pre-C and BCP mutations frequently occur in patients with genotype C1. HBV genotype C, pre-C mutations and BCP mutations are closely related to the occurrence of HCC.

Open access

Guang-Quan Chen, Liang Yi, Xing-Yong Xu, Hong-Jun Yu, Jian-Rong Cao, Qiao Su, Lin-Hai Yang, Yong-Hang Xu, Jun-Yi Ge and Zhong-Ping Lai

Abstract

It has been suggested that the standardized growth curve (SGC) method can be used to accurately determinate equivalent dose (De) and reduce measurement time. However, different opinions regarding the applicability of the SGC method exist. In this paper, we evaluated quartz OSL SGCs of marine and coastal sediments of different grain sizes and different cores in the south Bohai Sea in China, and tested their applicability to the determination of De values. Our results suggested as follows: (1) The SGC method is applicable to both multiple- and single-aliquot regenerative-dose (MAR and SAR) protocols of OSL dating and efficiently provides reliable estimates of De. (2) Finesand quartz of different palaeodoses showed highly similar dose-response curves and an SGC was developed, but old samples using the SGC method have large uncertainties. (3) For coarse-silt quartz, two different types of dose-response curves were recorded: low-dose (≤60Gy) and high-dose (≥100Gy). The growth curves of low-dose quartz were similar to each other, facilitating the use of SGC in De estimations, but errors tended to be larger than those obtained in the SAR method. For high-dose (100–300Gy) quartz, the SGC was also found to be reliable, but there was large uncertainty in De (>300Gy) estimation. We suggest that SGC could be employed for the dating of marine and coastal sediments dating using either MAR or SAR OSL protocol and either fine-silt, coarse-silt or fine-sand quartz.

Open access

Ming-hui Li, Yao Xie, Yao Lu, Guo-hua Qiu, Lu Zhang, Ge Shen, Li-wei Zhuang, Ju-long Hu, Jian-ping Dong, Cai-qin Mu, Lei-ping Hu, Li-jun Chen, Xing-hong Li, Min Yang, Yun-zhong Wu, Hui Zhao, Shu-jing Song, Jun Cheng and Dao-zhen Xu

Abstract

Objective To investigate the effects of individualised treatment with peginterferon alpha-2a (40 kD) plus ribavirin in Chinese patients with CHC.

Methods Total of 297 consecutive Chinese patients were enrolled, including 250 naïve cases and 47 cases who were previously treated. Treatment duration was determined according to viral genotypes, prior treatment history and viral responses at week 4, 12 and 24.

Results Totally, 235 patients (79.1%) completed treatment and 186 (87.3%) achieved SVR. And 219 out of 289 (75.8%) patients achieved HCV RNA negative at week 4 (RVR) and 259 of 276 (93.8%) at week 12. Among the 164 patients with RVR who completed follow-up, 158 (96.3%) achieved SVR. Patients with RVR had lower baseline viral loads than patients without RVR (P = 0.034). The positive predictive value (PPV) of RVR for SVR was 90.7% (OR 2.10 vs. non-RVR, 95% CI: 0.50 - 8.7). Similar outcomes were observed among patients with HCV undetectable at week 12.

Conclusions Complete viral suppression by week 4 is associated with a high rate of treatment success in treatment naïve and experienced patients receiving individualized CHC therapy.