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For the design of superconducting magnets, the magnetic field and critical current distributions are usually calculated based on finite element software such as COMSOL, ANSYS, etc. These software are necessary for accurate structure modeling and field calculation, but they occupy large memory space and comsume long simulation time. Furthermore, they are not easy to use. To achieve an easy-to-implement solution for rapid magnet field and critical current calculations, this paper investigates three types of analytical calculating methods, and builds an autonomously-operated calculating application program (APP) for the uses in various superconducting magnets.

The shortage of dc protection device limits the development of dc grids. This letter proposes a novel superconducting magnetic energy storage (SMES)-based transformerless series voltage restorer (TLSVR) for dc-load protections. The proposed SMES-TLSVR is made up mainly of a bidirectional-switch-based converter and a superconducting coil, and is interfaced in the series with the dc transmission line. It has the advantages of duplex voltage compensation ability, transformerless structure, and swift compensation response, and has a wider compensation range than traditional voltage-fed transformerless dynamic voltage restorer. The topology, circuit principle, and control strategy are elaborated in this letter. Finally, a kW-class SMES prototype is carried out to verify the feasibility of the proposed SMES-TLSVR.

This article analyzed the losses from the saturated iron-core superconducting fault current limiter (SISFCL) which could be potentially applied into a Voltage Source Converter based High Voltage Direct Current (VSC-HVDC) network. The mathematical model of SISFCL and the loss computation on High Temperature Superconducting (HTS) parts have been performed based on the FEM (finite-element method) combined with H-formulation solved by the COMSOL. Before the FEM modelling of SISFCL, the fault current statues were modeled using PSCAD. The operation performance of SISFCL was simulated as well based on the electromagnetic characteristics analysis, and the power dissipations in the HTS coils of SISFCL were calculated. Results demonstrate even with a DC system, there were certain amounts of loss happened in the HTS coils of SISFCL, if the SISFCL encountered a considerably high fault current.

This paper shows a new model of the anisotropic field dependence for modeling the High Temperature Superconductor (HTS) based Conductor on Round Core (CORC) transmission Cables. The modeling of CORC Cable was carried out using the finite-element method (FEM) and H-formulation model which put into the software COMSOL. This new model with the field dependence model was tested for both the 2D and 3D models of CORC cables. The simulations were performed with different conditions, e.g. different transport current and the gap angle between each HTS wires. This new field dependence model can contribute a good approximation of the real operating performance of CORC cables, and also build an upper limit of the AC loss. This model could be really beneficial for the design of CORC cables.

This paper presents the preliminary experiments of a cryogenic boost chopper based on low-resistance MOSFETs and zero-resistance ReBCO inductor under 77K. Three cryogenic operating behaviors of on-state resistances and breakdown voltages of commercial MOSFETs and on-state voltage across their built-in reverse diodes are experimentally investigated to demonstrate the technical feasibility of cryogenic power conversion. Being verified by extremely low conducting resistances under 77 K, two cryogenic power MOSFETs and one ReBCO inductor are subsequently used to develop a cryogenic boost chopper circuit. The experimental results obtained by different circuit schemes and testing conditions show that the overall power conversion efficiency in the cryogenic boost chopper is improved by about 7% than that in conventional boost chopper. These preliminary experiments lay some technical bases for maximizing the operating efficiencies in superconductor-semiconductor-coupled cryogenic power electronic interface towards smart DC microgrids.

This paper studied the Na2O-B2O3-SiO2-CaO-P2O5-F glass-ceramics and obtained the complex biological glass-ceramics with low sintering temperature, high mechanical properties and good biological activity. In this paper, the better basic point was selected in phase region of Na2O-B2O3-SiO2 glass system. It was studied that the effect of different percent of CaO, P2O5 and F addition on the mechanical properties and biological activity of the glass-ceramics. The glass powder was prepared by melting and quenching in water, and then by molding and sintering, composite glass-ceramics materials was obtained. With the help of DSC, XRD and SEM analysis methods and testing means, the phases and heat treatment systems of the material were determined, and the microstructure of materials in the different heat treatment conditions was observed. The biological activity was tested in SBF simulated body fluid . Research shows that: the introduction of F can effectively reduce the melting temperature of the material and is helpful to crystallization. The introduction amount of CaO, P2O5 and F can affect the biological activity of glass-ceramics. In the range of introducing CaO, P2O5 and F in this paper, the mechanical properties and biological activity of glass-ceramics increase with the amount of the introduction of CaO, P2O5 and F.

mproving energy efficiency is an important way of energy saving and emission reduction. Great achievements have been obtained by the First Long-term Agreements on Energy Efficiency (short for LTA1) of Netherlands in this regard. Whats more, it deserves to learn. The history, structure, operation process, achievements and deficiencies of LTA1 are analyzed systematically, and the enlightenments about how to improve energy efficiency in China will also be provided in this paper.

To explore the effect of asthmatic and healthy serum on differentiation and function of monocyte-derived dendritic cells (MDDC) in a transendothelial trafficking model.The sera and peripheral blood mononuclear cells (PBMC) were separated from 12 asthmatic patients and 12 healthy volunteers, and monocytes were selected from PBMC using magnetic beads. The trypsin-digested human umbilical vein endothelial cells (HUVEC) at passage 2 from 5 healthy lying-in women were used to construct the transendothelial trafficking model under asthmatic or healthy serum, wherein MDDC were identified by silver nitrate staining and scanning electron microscopy. Nuclear factor κB (NF-κB) activity was determined by electrophoretic mobility shift assay. Flow cytometry, ELISA and mixed leukocyte reaction were relevantly utilized to detect the phenotype, cytokine and T cell proliferation.(1) Monocytes traversed through HUVEC monolayer after 2 h, and reverse-transmigrated to develop into DC 48 h later. (2) The healthy serum stimulated monocytes into immature MDDC with lower CD(14) [(20 ± 5)%] (F = 49.01, P0.05), and higher HLA-DR, CD(80), CD(86) and CD(83) [(43 ± 4)%, (17.9 ± 3.5)%, (43 ± 11)% and (6.7 ± 1.8)%, respectively] (F = 10.35 - 40.17, all P0.05) than monocytes did before transmigration at 0 h [CD(14) (81 ± 6)%, HLA-DR (24 ± 5)%, CD(80) (2.8 ± 2.0)%, CD(86) (14 ± 4)% and CD(83) (0.9 ± 0.8)%, respectively]. (3) The asthmatic serum stimulated monocytes into mature MDDC, characteristic of dendrites, with similar HLA-DR and CD(86) [(55 ± 6)% and (59 ± 12)%] (F = 15.29 and 35.97, all P0.05), higher CD(80) and CD(83) [(49.7 ± 10.2)% and (30.2 ± 6.8)%] (F = 4.01 and 20.68, all P0.05), accompanied by increased levels of NF-κB activity, IL-12 p70 and T cell proliferation [(100 ± 11)%, (568 ± 43) ng/L and (2033 ± 198) cpm, respectively] (F = 49.23 - 350.84, all P0.05) relative to the healthy serum-stimulated immature MDDC [(12 ± 3)%, (220 ± 35) ng/L and (952 ± 64) cpm, respectively].The asthmatic serum induces mature MDDC in association with NF-κB overactivation in the transendothelial trafficking model, which provides a promising experimental platform for both investigation of immunological mechanisms in asthma and screening of novel anti-asthma drugs in vitro.

To evaluate the differentially expressed genes between the Stress fracture (SF) cases and controls.Total RNA was extracted and purified from peripheral blood sample of 3 SF cases and 3 controls who conducted a 1:1 matched case-control study, then used for Human Genome Array analysis. The hybridization data were analyzed using SAM software. Parts of these genes were analyzed and identified by real-time PCR.Upregulated and downregulated genes were 22 and 1, respectively. Thus the highest ratio and most significant cytokine was tumor necrosis factor receptor superfamily, member 10c (TNFRSF10C). The result of real-time PCR shows that TNFRSF10C was over-expressed in 3 cases and low-expressed in 1 case.Obvious difference exists in gene expression between SF cases and controls, showing there may be a lot of genes involving in the occurrence and development of SF. Meanwhile, the identification of the specific genes is helpful for biomechanics study, early diagnosis and screening of SF.

To investigate the effects of adenoviral gene transfer of IkappaBalpha mutant (IkappaBalphaM), a novel inhibitor of nuclear factor kappaB (NF-kappaB), on apoptosis, phenotype and function of human monocyte-derived dendritic cells (DC).Monocytes, cocultured with granulocyte/macrophage colony-stimulating factor (GM-CSF; 900 ng/mL) and interleukin (IL)-4 (300 ng/mL) for 5 d, followed by stimulation with lipopolysaccharide (LPS; 100 ng/mL) for 2 d differentiated into mature DC. Monocytes were either left untransfected or were transfected with AdIkappaBalphaM or AdLacZ. The transcription and expression of the IkappaBalphaM gene, and the inhibitory effect of IkappaBalphaM on tumor necrosis factor (TNF)-alpha-induced NF-kappaB activation in mature DC were detected by polymerase chain reaction (PCR), reverse transcription-polymerase chain reaction (RT-PCR), Western blot analysis, and electrophoretic mobility shift assays, respectively. The phenotype, apoptosis, IL-12 secretion level of DC, and ability to stimulate the proliferation of T cells were determined by flow cytometry, enzyme-linked immunosorbent assay and mixed leukocyte reaction.PCR and RT-PCR were used to detect a unique 801 bp band in AdIkappaBalphaM-transfected mature DC, and also a dose- and time-dependent expression of the IkappaBalphaM gene, which peaked at a multiplicity of infection of 100 pfu/cell and at 48 h. Furthermore, AdIkappaBalphaM significantly suppressed the TNF-alpha-induced NF-kappaB activation, augmented apoptosis, downregulated CD80, CD83, and CD86 surface molecules, IL-12 secretion levels and the ability to stimulate the proliferation of T cells in mature DC.AdIkappaBalphaM effectively transfected and potently inhibited NF-kappaB activation in monocyte-derived mature DC. Overexpression of the IkappaBalphaM gene in mature DC may contribute to T-cell immunosuppression through induction of DC apoptosis and downregulation of B7 molecules, providing a potential strategy for future DC-based immunotherapy of asthma.

The role played by cytokines, other than interferon (IFN)-α, in the differentiation and function of dendritic cells (DCs) in systemic lupus erythematosus (SLE), remains unclear. Serum interleukin-10 (IL-10) levels are generally elevated in SLE patients, which might modulate the differentiation of DCs. In this study, DCs were induced from monocytes either by transendothelial trafficking or by culture with granulocyte-macrophage colony-stimulating factor (GM-CSF) + IL-4 + tumor necrosis factor (TNF)-α. Both systems were used to investigate the effects of elevated serum IL-10 level on DC differentiation in SLE patients. The results showed that monocyte-derived DCs induced by either SLE serum or exogenous IL-10 reduced the expression of human leukocyte antigen (HLA)-DR and CD80, decreased IL-12p40 level, and increased IL-10 level, and exhibited an impaired capacity to stimulate allogenic T-cell proliferation. These results indicate that serum IL-10 may be involved in the pathogenesis of SLE by modulating the differentiation and function of DCs.