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A step-up control method is proposed to solve the problem of the normalized voltage gain less than 1 when the bi-directional LLC resonant converter works in backward mode. This step-up control method turns on rectifier switches to help resonant components recover their energy and improves the normalized voltage gain to 2. Working principle of the bidirectional LLC resonant converter is introduced firstly. The working procedures under continuous mode and discontinuous mode are analyzed and deduced in detail too. In the end, a 3kW prototype is built up for UPS battery charger application. The MATLAB simulation and experiment results show that this proposed bidirectional LLC resonant circuit works with a high efficiency and the normalized voltage gain can be greater than 1 in the backward operation. Certainly, most of the switching devices can still achieve soft switching at the same time.

This paper proposes a three-phase six-inductor double-switch PFC circuit which is suitable for high frequency UPS application. This PFC circuit not only achieves high power factor correction in grid-connected mode of UPS, but also improves bus voltage in battery mode of UPS. This new PFC removes the independent boost design in common UPS and the whole cost can be reduced. The topology structure and working procedures of this PFC circuit are introduced and analyzed in detail. The main circuit parameters and LCL filter are designed for a 5kW PFC prototype. The MATLAB simulation and experiment results show that this PFC circuit is easy to control with less switches, and woks in good input power factor and low current harmonic distortion.

LLC series resonant topology has been widely adopted in many kinds of power converters for its high frequency, high efficiency and high power density advantages. However, the ordinary topology of a single-phase LLC is not fit to be used in low-voltage high-current output field for its relative larger output voltage ripple. In order to provide a low voltage and high current output using a LLC topology, a novel interleaving LLC switched-mode power supply design was proposed to reduce output voltage ripples ripple in this paper. This design used two hardware measures to automatically ensure a good load current sharing effect between two-branch LLC circuits and avoid the PFM difficulties of the active current sharing methods. The principles and design procedures of this novel LLC converter were introduced in detail and verified by Saber simulation results. A 1.5kW DC/DC prototype was built up in the end and the experiment results showed that a good current sharing performance was achieved.

The transforming growth factor beta (TGF-β) superfamily exerts a wide range of effects on biological events, including spermatogenesis. Smad proteins are downstream signal mediators, which transduce TGF-β signals from the cell surface to the nucleus. Smad4 protein is the common transducer of the TGF-β superfamily that participates in the signaling of all the members of TGF-β superfamily. Smad4 is expressed in the mammalian testis and is believed to play an important role during testicular development and spermatogenesis. Information about Smad4 distribution and function in the testis of birds, including the domestic fowl, is still unclear. In the current study, our objective was to clarify the signal transduction pathway of the TGF-β superfamily in the regulation of testicular development and spermatogenesis by investigating the expression of Smad4 protein in the testis of newborn, prepuberty, puberty and adult domestic fowl. Cellular localization of Smad4 was determined by immunohistochemistry. Our study revealed that the Smad4 was widely expressed in the fowl testis, mainly immunolocalized in the cytoplasm of Sertoli cells, Leydig cells and germ cells. The presence of Smad4 protein in these testicular cells provides molecular and morphological evidence for TGF-β signal transduction during testicular development and spermatogenesis.

Ovarian follicular development, follicle selection, and the process of ovulation remain poorly understood in most species. Numerous endocrine, paracrine, and autocrine factors, including the ligands represented by the transforming growth factor β (TGFβ) superfamily, TGFβ, activin, inhibin, bone morphometric protein (BMP), and growth differentiation factor (GDF) are present in the ovaries of many animals. In the present study, we investigated the immunolocalization of Smad4, a signaling molecule of the TGFβ superfamily, during folliculogenesis in the ovary of the European hedgehog (Erinaceus europaeus L., 1758). Immunolocalization studies revealed that Smad4 was widely seen in the ovary, mainly in the follicle, though its location and staining intensity varied with the different stages of the developing follicle. In the primordial follicles and early growing follicles, Smad4 protein was mainly localized in the cytoplasm of the oocyte with a half-moon staining pattern. In the pre-antral follicles, Smad4 protein was mainly located in the granulosa cells, theca cells and diffusely distributed in the interstitial cells surrounding the follicle. In the corpora lutea, the immunostaining for Smad4 was very intense. These results suggested that Smad signal transduction may play an important role in folliculogenesis and conceivably may participate in subsequent pregnancy.

Summary The expression and localisation of downstream signalling molecules of transforming growth factor beta superfamily, Smad2 and Smad4 proteins, was investigated in immature and mature dog testis. Cellular localisation of Smad2 and Smad4 proteins was examined using immunohistochemistry. Quantitative analysis of immunostaining was determined by the image analysis system. The specificity of the antibodies was examined using Western blotting assay. Smad2 and Smad4 were widely expressed in the testes, mainly immunolocalised in the cytoplasm of gonocytes, Leydig cells and Sertoli cells of immature testes, and Leydig cells and Sertoli cells of mature testes. At the same time, the expression levels for both proteins were different between immature and mature age groups: the expression of Smad2 and Smad4 proteins in the Sertoli cells of mature testis was higher than in the immature group (P

Background: Rheumatoid arthritis (RA), an autoimmune disease, is characterized by pronounced inflammation and cell accumulation within affected joints. Beneficial effects of active ingredients of the astragalus root (Radix astrogali) in treatment of immunological diseases have been previously observed, but the mechanisms are not well understood. This study aims to evaluate therapeutic effects and the mechanisms of astragalus polysaccharides (APS) on adjuvant-induced arthritis (AA) in rats. Methods: Effects of treatment of AA rats with increasing doses of APS, Tripterygium glycosides (positive control) and saline (negative control) on swelling, arthritic index, synovial cell accumulation, serum concentrations of tumor necrosis factor α (TNF-α) and interleukin-1β (IL-1β), synovial apoptosis and immunostaining for Bcl-2 and Bax were determined. Results: APS treatment reduced cell accumulation, swelling and arthritic index of the joints and serum concentrations of TNF-α and IL1-β in a dose-dependent manner in AA rats. Synovial cell apoptosis was elevated in response to APS treatment and accompanied by increased staining for pro-apoptotic Bax protein and decreased staining for anti-apoptotic Bcl-2 protein. Conclusions: APS treatment reduced multiple indices of arthritis in rats with AA. Results support further investigation of therapeutic effects of APS in treatment of RA and other autoimmune diseases.

Amplified consensus genetic markers (ACGM) is a novel PCR-based DNA molecular marker technique, which is based on the conservation of coding sequences and the potential polymorphism within non-coding sequences in homologous genes among closely related species. Along with the rapid development of comparative genomics and bioinformatics, the ACGM technique has already become a powerful tool for comparing homologous genes, analyzing phylogenetic relationships among species, and mapping of genes of interest. Here, an introduction to ACGM technique, especially its application in Brassica genera and Gramineae, was presented in detail. The prospects of ACGM were also discussed.

Seventeen compounds derived from traditional Chinese medicines (TCMs) were tested for their antiviral activity against porcine reproductive and respiratory syndrome virus (PRRSV) in vitro. Visualization with the cytopathologic effect (CPE) assay and the 3-(4, 5-dimethyithiazol- 2-yl)-2,5-diphenyltetrazolium bromide test were used to determine the 50% cytotoxic concentration (CC50) and 50% effective concentration (EC50) in cultured Marc-145 cells. Among the tested compounds, chlorogenic acid and scutellarin showed potential anti-PRRSV activity. The EC50 values were 270.8 ± 14.6 μg/ml and 28.21 ± 26.0 μg/ml and the selectivity indexes were >5.54 and 35.5, respectively. The time-of-addition and virucidal assay indicated that the anti-PRRSV activity of the two compounds could be due to their inhibiting the early stage of virus replication and/or inactivating the virus directly. The inhibition of the virus attachment was not observed in the adsorption inhibition assay. The inhibition ratios of chlorogenic acid and scutellarin were, respectively, 90.8% and 61.1% at the maximum non-cytotoxic concentrations. The results have provided a basis for further exploration of their antiviral properties and mechanisms in vivo. We believe that the chlorogenic acid and scutellarin have a great potential to be developed as new anti-PRRSV drugs for clinical application.

DC micro-grid, as a self-management grid form of integrating distributed energy systems with utility power systems, will efficiently realize the value and benefit of the distributed energy resources. In this paper,the DC micro-grid mainly consists of five parts: a PV source, a DC/DC converter, a battery energy storage unit, a bi-directional DC/DC, and a bi-directional DC/AC which is connected to the main grid. This DC micro-grid has different control strategies according to different operating modes (grid connected, islanded). Then its control mode is designed and investigated by MATLAB/Simulink models. The simulation results verify the validity of the mathematical model and the feasibility of the proposed control strategies. In the grid connected mode, the transfer energy can flow in bi-directional modes, and DC bus voltage level can be stabilized by DC/AC converter. In the islanded mode, the battery converter serves as a voltage source to ensure a stable DC voltage. At last, DC micro-grid experimental system is used to examine its switching functions among different control modes. The experimental results demonstrate that high quality power can be supplied.

Growth differentiation factor 9 (GDF9) is an oocyte-derived factor critical for folliculogenesis. Recently, in vitro data showed that GDF9 inhibited the localization of tight junction (TJ) proteins, suggesting that GDF9 could potentially regulate spermatogenesis in vivo, via inhibition of Sertoli cell TJ function. The purpose of the present study was to determine the expression and localization of GDF9, its receptor, ALK5, and its latent target protein, claudin-11 (one of TJ proteins) in adult alpaca testis using Western blot and immunohistochemistry. Western blotting results demonstrated that GDF9, ALK5 and claudin-11 were expressed in the adult alpaca testis. Immunohistochemistry revealed that GDF9 was expressed stage-specifically in the cytoplasm of pachytene spermatocytes and round spermatids of the adult alpaca seminiferous epithelium. Type I receptor, ALK5 was mainly localized in the cytoplasm of round spermatids and Leydig cells, and to a lesser extent in the cytoplasm of pachytene spermatocytes and Sertoli cells. Its latent target protein, claudin-11, was perpendicular or parallel to the basal lamina in the basal part of Sertoli cells. These results indicated that GDF9, as a paracrine and autocrine growth factor derived from round spermatids and pachytene spermatocytes, is involved in regulating spermatogenesis via action on germ cells or somatic cells (i.e. Leydig cells, Sertoli cells).

Rheumatoid arthritis (RA), an autoimmune disease, is characterized by pronounced inflammation and cell accumulation within affected joints. Beneficial effects of active ingredients of the astragalus root (Radix astrogali) in treatment of immunological diseases have been previously observed, but the mechanisms are not well understood. This study aims to evaluate therapeutic effects and the mechanisms of astragalus polysaccharides (APS) on adjuvant-induced arthritis (AA) in rats.Effects of treatment of AA rats with increasing doses of APS, Tripterygium glycosides (positive control) and saline (negative control) on swelling, arthritic index, synovial cell accumulation, serum concentrations of tumor necrosis factor α (TNF-α) and interleukin-1β (IL-1β), synovial apoptosis and immunostaining for Bcl-2 and Bax were determined.APS treatment reduced cell accumulation, swelling and arthritic index of the joints and serum concentrations of TNF-α and IL1-β in a dose-dependent manner in AA rats. Synovial cell apoptosis was elevated in response to APS treatment and accompanied by increased staining for pro-apoptotic Bax protein and decreased staining for anti-apoptotic Bcl-2 protein.APS treatment reduced multiple indices of arthritis in rats with AA. Results support further investigation of therapeutic effects of APS in treatment of RA and other autoimmune diseases.

Oocyte-secreted growth differentiation factor (GDF) 9 plays an essential role during follicle maturation through actions on granulosa cells. Despite its critical role in female reproduction, GDF9 expression, signalling and function are less well characterized during spermatogenesis. The purpose of this study was to investigate temporal and spatial expression and potential cellular targets of GDF9 in the adult cat testis. Our result confirmed that GDF9 is stage-specifically localized in the cytoplasm of round spermatids and pachytene spermatocytes of the cat seminiferous epithelium. In particular, activin receptor-like kinase (ALK) 5, the type I receptor of GDF9, is principally localized in the cytoplasm of round spermatids. Smad2/3, signal transducers for GDF9 signalling pathway, is mainly immunolocalized in the cytoplasm of germ cells, Sertoli cells and Leydig cells, but the expression in germ cells are weaker than in Sertoli cells. The expression pattern of ALK5 and Smad2/3 show that GDF9-ALK5-Smad2/3 may not be the only signalling pathway for testicular cell to respond to GDF9. Overall, our results demonstrate that GDF9 is a germ cell-specific factor in the adult cat testis, and that GDF9 regulates the tight junctions of Sertoli cells by paracrine secretion, and regulates the germ cells by autocrine secretion.

As an efficient strategy for gene isolation, map-based cloning has been widely applied and well advanced in crops with small genomes. However, the application of this strategy is challenging in crops with large genomes that are rich in repetitive DNA. Because of the importance of map-based cloning, its basic contents and development are summarized. In particular, the application of this strategy is analyzed and evaluated in large genome crops, and the potential directions of its development are discussed. These help to promote genes cloning in large genome crops.

Treatments of unilateral lambdoid synostosis and unilateral coronal synostosis.Approach to coronal, double frontal flaps were rotated with orbit advancement and anteversion of the frontal to enlarge the volume of ante cranial fossa., and reconstruct the contour of orbit and the frontal. The gap was between the frontal and parietal to reconstruct the coronal suture after fixation and reconstruction of the frontal os. For post plagiocephaly, double rotated occipital flap and plum-plasty flap were performed to reconstruct the occiput. The gap between the parietal and occiput was to reconstruct the lambdoid suture.Eight cases have favourable prognosis with satisfactory contour.It is optimal to use frontal flap rotation, orbit advancement and frontal anteversion to correct the unilateral coronal synostosis. Bilateral rotated occipital-parietal crossing flap and plum-plasty were performed to reconstruct the occiput. Keeping the gap between the parietal and occiput for reconstruction of the lambdoid suture is suitable to infant.

To investigate the technique of skull reconstruction for the congenital craniosynostosis.Many technique of skull plasty were adopted to correct the congenital craniosynostosis. We advanced fronto-orbital, reversal change of the frontal bone to correct the brachycephalic, hydrocephaly acrocephaly, which were supported by parietal bone. Plum-plasty of the calvaria was performed for sagittal synostosis; Fronto-orbital plasty correct the trigonocephaly; for single coronal synostosis, which result to frontal plagiocephaly,we reversed both frontal sides, advanced orbital strip and tilted the invalid side . The post plagiocephaly because of single Lambdoid synostosis, we performed of plum-plasty, reversal change of total occipital. Fronota-facial advancement cured the brachycephalic complicating with Apert or Crouzon which caused by coronal synostosis and cranial basal suture synostosis.37 cases were recovery without complication. The figures were improved.Big calvarial flap plasty is an optimal technique to correct the congenital craniosynostosis. But it is not substituted by bone lengthening and minimally invasive technique.

To study the technique of total calvaria reconstruction for sagittal synostosis.11 children with sagittal synostosis were treated. The David II procedure was used to reconstruct the calvarial gap in 6 cases; Osteotomies with reversal change was performed on 2 cases; Plum-plasty of the calvaria was performed on 3 cases.The 11 cases were cured with satisfactory head shape.The David II procedure is applicable for patient of 1 approximately 3 months. The technique of floating skull flap plasty and plum-plasty of the calvaria can be performed on patients older than 3 months.

In the present study, an assay using Polymerase Chain Reaction (PCR) was developed for the detection of Staphylococcus aureus in meat. Based on flotation and solvent extraction technology, FTA filter was used to extract S. aureus DNA from artifically contaminated meat. Primers targeting the thermostable nuclease gene (nuc) were used to amplify a 279 bp DNA fragment which was confirmed by DNA sequencing. The detection limit of PCR was 10 cfu x g(-1) meat of S. aureus. This novel FTA-PCR assay allows for detection of Staphylococcus aureus in meat in6 h, which is 12-24 h less than that of conventional PCR with enrichment method. Seventy-two samples were analyzed and the detection rate using the standard cultivation method was 70.8%, detection time was 5d. The detection rate of PCR amplification using filters was 73.6%, detection time was 6h. The detection rate of Baird-Parker R.P.F method was 69.4%, detection timewas 18 h. The detection rate of petrfilm RSA method was 61.1%, detection time was 18 h. Thus PCR amplification using filters provides a faster and more sensitive method of S. aureus detection than the standard cultivation method. At the same time,it provides an universal process for preparing DNA template.

Blood samples from 23 Huacaya alpacas, 3 males and 20 females, were used to study chromosomes and karyotypes, so as to provide some effective cytogenetic bases for the selection, improvement by crossing, disease diagnosis of alpacas, and genetic mechanisms of sex determination. Peripheral blood lymphocyte culture was used to prepare chromosome. A method of trypase-EDTA was used for G-banding. The results showed as follows: The number of diploid chromosomes was 2n=74, with the karyotype 74, XY and 74, XX for males and females respectively. Thirty-six homologous pairs of chromosomes were autosomes, in which chromosomes pairs No.1 to No.20 were acrocentric-subterminal and No.21 to No.36 metacentric-submetacentric. And X chromosome was metacentric, Y chromosome telocentric. The analysis of G-bands showed that bright and dark bands appeared by turn. It showed different bands. And every pair of chromosomes had its distinct band, and the longer the chromosomes, the more the number of bands, and the more clear the bands.