Search

In view of problem that traditional PID control for synchronous generator cannot meet with requirements of oscillation suppression and improvement of dynamic stability limit of power system, the paper proposed the optimal excitation control method for synchronous generator based on AC tracking. It gave deviation and linearization model of excitation system of synchronous generator based on Lagrange method, analyzed definition method of the optimal excitation control quantity and built simulation model of synchronous generator system based on the control method. The simulation result showed that the control method can real-timely control excitation system of synchronous generator to ensure output stability of synchronous generator comparing with traditional PID control method.

In view of shortcomings of traditional testing methods of automatic voltage regulator such as few test items, poor security, high construction cost, big difference in equipment parameters, a design scheme of new general testing system of automatic voltage regulator based on LabWindows/CVI was put forward. Structure and principle of the testing system were introduced. The testing system realizes AVR dynamic test and has many advantages such as complete testing project, short testing circle, preferable universality and so on compared with traditional testing systems.

The winged pearl oyster, Pteria penguin, is a widely distributed large pearl oyster species, which can produce large-sized mabé (half-pearl), and exhibit strong tolerance to severe environment. However, genetic improvement of P. penguin was still in its infancy. In this study, the correlation between five microsatellite loci and four growth traits (shell height, shell length, shell width and total weight) of 500 winged pearl oysters were analyzed by One-way ANOVA. Multiple comparisons between different genotypes of microsatellite markers and growth traits were performed. It was shown that the 5 loci in this study are all highly polymorphic loci, among which, QEB-D15 and CL-232 were extremely significantly associated with the shell width of the winged pearl oyster (P<0.01). The individuals with genotype 239/263 and 239/273 at QEB-D15 had the maximum and the minimum shell width, respectively. The 263 bp allele might positively correlate with the shell width, while the 273 bp allele might negatively correlate with the shell width. The average values of shell length, shell width and total weight of individuals with genotype 157/174 at locus CL-232 were larger than that of other genotypes, suggested that this genotype was the dominant genotype. Individuals with genotype of 177/192 at locus CL-232 had the smallest shell length, shell width, shell height and total weight, indicated that the 177/192 may be an inferior genotype. In addition, the shell width is correlated with two SSR loci, which indicates that the shell width is a phenotypic trait that may not be controlled by a single gene. This study could provide valuable information for molecular marker-assisted selection of P. penguin. [ABSTRACT FROM AUTHOR]

Autoimmune diseases are characterized by damage and dysfunction of multiple organs and various complications. Recently, new therapies for autoimmune diseases have been proposed extensively, and there are growing researches focusing on the immunomodulatory abilities of mesenchymal stem cells (MSCs). As a kind of small vesicles secreted by cells, exosomes can be released by MSCs and other cells. Being enriched with protein, mRNA, microRNA, lipids and other cell contents, exosomes participate in the transfer of substances and information between cells, and regulate the biological functions of recipient cells, which may be a potential mechanism of the immunomodulation abilities of MSCs. A growing number of studies have shown that the exosomes secreted by MSCs have similar or even better immunomodulation abilities than MSCs, and their roles in the treatment of several autoimmune diseases have been confirmed in animal models. In this review, we briefly summarize the effects of MSCs and the MSCs-derived exosomes on the immune system and immune cells, especially focusing on the research progress of MSCs-derived exosomes in autoimmune diseases in recent years.

Exosomes are nanometer-sized membranous extracellular vesicles that can be secreted by almost all types of cells in the body. Exosomes are involved in cell-to-cell communication through autocrine and paracrine forms. Exosomal microRNAs (miRNAs) are stable in plasma, urine and other body fluids, and have various biological functions. They play an irreplaceable role in the occurrence, development, immune regulation of systemic lupus erythematosus (SLE). Recent studies have proposed that exosomal miRNAs have promising application prospects in the pathogenesis, early diagnosis, and treatment of SLE. Therefore, this review aims to introduce the current research progress on exosomal miRNAs in SLE and analyze their potential application value.

Objective: To investigate the effects of umbilical cord mesenchymal stem cell (UC-MSCs) transplantation on interstitial pneumonitis in MRL/lpr mice., Methods: Twenty four 18-week-old MRL/lpr female mice were randomly divided into 3 groups: the single dose group received a single dose of UC-MSCs (1 x 10(6)) transfusion intravenously, the 3 dose group received 3 injections of UC-MSCs (1 x 10(6)) weekly for 3 weeks, and the control mice were treated with saline. Both the control and the treated mice were sacrificed at 29 weeks. The histopathology of the lungs were assessed by HE staining., Results: In comparison to the control mice, UC-MSCs transplantation significantly attenuated interstitial pneumonitis in the MRL/lpr mice. The peribronchiolar lesion indices of the single dose treatment group (1.40 +/- 0.24) and the 3 dose treatment group (1.02 +/- 0.29) were significantly decreased as compared to the control group (1.95 +/- 0.35), q = 0.551, 0.937, all P < 0.01. The perivascular lesion index of the single dose treatment group (1.20 +/- 0.18) and the 3 dose treatment group (1.08 +/- 0.16) were also significantly reduced as compared to the control group (1.56 +/- 0.32), q = 0.360, 0.479, P < 0.05, P < 0.01. The inflammatory cell infiltration index of the control group (1.72 +/- 0.34) was significantly increased compared to the single dose treatment group (1.30 +/- 0.21) and the 3 dose treatment group (1.05 +/- 0.15), q = 0.417, 0.673, P < 0.05, P < 0.01., Conclusions: These findings indicate that UC-MSCs have a pleiotropic therapeutic effect on pneumonitis in MRL/lpr mice.