Practical Teaching Method Based on MATLAB in AC Speed Regulating System Course

Because an AC speed regulating system is abstract and complex, the study on practical teaching method based on MATLAB software is quite necessary in the AC speed regulating system course at our university. The permanent magnet synchronous motor (PMSM) vector control system is taken as an example to explain in details the practical teaching method based on MATLAB. The course content is divided into several knowledge modules based on speed regulation methods. The concept of subsystem in Simulink is introduced. Each type of speed regulating systems can be divided into several subsystems according to its functions. The control principle, system constitution and design method of each AC speed regulation system is explained by different function subsystems. The instructor vividly demonstrates the control system simulation model of AC speed regulation systems in class, and the students establish and modify the existing simulation model by themselves on the computers under the guidance of the instructor. In this way, the students\u27 practical ability and teaching quality of specialized courses can be improved greatly

Variant rs2200733 and rs10033464 on chromosome 4q25 are associated with increased risk of atrial fibrillation after catheter ablation: Evidence from a meta-analysis

Background: Common genetic polymorphisms at chromosome 4q25 were associated with increased susceptibility to atrial fibrillation (AF). However, it remained controversial whether these variants could be used as risk predictors for AF recurrence after catheter ablation. We therefore performed a metaanalysis to quantify the association between rs2200733 C>T/rs10033464 G>T and AF recurrence. Methods: Relevant studies were systematically retrieved from PubMed, Web of Science, Elsevier database and Cochrane library through November 2016. Data were abstracted and pooled using Stata 12.0 software. Results: A total of 2,145 patients undergoing catheter ablation were included. Patients with rs2200733 TT or TT+CT showed an overall increased susceptibility to AF recurrence (homozygous model [TT vs. CC]: odds ratio [OR] = 2.03, 95% confidence interval [CI] 1.49–2.76, p = 0.000; dominant model [TT+TC vs. CC]: OR = 1.48, 95% CI 1.17–1.87, p = 0.001; recessive model [TT vs. TC+CC]: OR = 1.88, 95% CI 1.12–3.15, p = 0.017). Subgroup analysis also identified a positive relation in Caucasians and late recurrence of AF in allelic, homozygous and dominant comparison. Moreover, a significant increased risk of AF recurrence was observed in patients with rs10033464 TG or TT+TG (heterozygous model [TG vs. GG]: OR = 1.46, 95% CI 1.01–2.12, p = 0.047; dominant model [TT+TG vs. GG]: OR = 1.51, 95% CI 1.04–2.17, p = 0.029). Conclusions: After catheter ablation, rs2200733 (TT or TT+TC) and rs10033464 (TT+TG or TG) were associated with increased risk of AF recurrence

Co-training with High-Confidence Pseudo Labels for Semi-supervised Medical Image Segmentation

Consistency regularization and pseudo labeling-based semi-supervised methods perform co-training using the pseudo labels from multi-view inputs. However, such co-training models tend to converge early to a consensus, degenerating to the self-training ones, and produce low-confidence pseudo labels from the perturbed inputs during training. To address these issues, we propose an Uncertainty-guided Collaborative Mean-Teacher (UCMT) for semi-supervised semantic segmentation with the high-confidence pseudo labels. Concretely, UCMT consists of two main components: 1) collaborative mean-teacher (CMT) for encouraging model disagreement and performing co-training between the sub-networks, and 2) uncertainty-guided region mix (UMIX) for manipulating the input images according to the uncertainty maps of CMT and facilitating CMT to produce high-confidence pseudo labels. Combining the strengths of UMIX with CMT, UCMT can retain model disagreement and enhance the quality of pseudo labels for the co-training segmentation. Extensive experiments on four public medical image datasets including 2D and 3D modalities demonstrate the superiority of UCMT over the state-of-the-art. Code is available at: https://github.com/Senyh/UCMT

UBXN3B Positively Regulates STING-Mediated Antiviral Immune Responses

The ubiquitin regulatory X domain-containing proteins (UBXNs) are likely involved in diverse biological processes. Their physiological functions, however, remain largely unknown. Here we present physiological evidence that UBXN3B positively regulates stimulator-of-interferon genes (STING) signaling. We employ a tamoxifen-inducible Cre-LoxP approach to generate systemic Ubxn3b knockout in adult mice as the Ubxn3b-null mutation is embryonically lethal. Ubxn3b(-/-), like Sting(-/-) mice, are highly susceptible to lethal herpes simplex virus 1 (HSV-1) and vesicular stomatitis virus (VSV) infection, which is correlated with deficient immune responses when compared to Ubxn3b(+/+) littermates. HSV-1 and STING agonist-induced immune responses are also reduced in several mouse and human Ubxn3b(-/-) primary cells. Mechanistic studies demonstrate that UBXN3B interacts with both STING and its E3 ligase TRIM56, and facilitates STING ubiquitination, dimerization, trafficking, and consequent recruitment and phosphorylation of TBK1. These results provide physiological evidence that links the UBXN family with antiviral immune responses

Zika Virus Non-structural Protein 4A Blocks the RLR-MAVS Signaling

Flaviviruses have evolved complex mechanisms to evade the mammalian host immune systems including the RIG-I (retinoic acid-inducible gene I) like receptor (RLR) signaling. Zika virus (ZIKV) is a re-emerging flavivirus that is associated with severe neonatal microcephaly and adult Guillain-Barre syndrome. However, the molecular mechanisms underlying ZIKV pathogenesis remain poorly defined. Here we report that ZIKV non-structural protein 4A (NS4A) impairs the RLR-mitochondrial antiviral-signaling protein (MAVS) interaction and subsequent induction of antiviral immune responses. In human trophoblasts, both RIG-I and melanoma differentiation-associated protein 5 (MDA5) contribute to type I interferon (IFN) induction and control ZIKV replication. Type I IFN induction by ZIKV is almost completely abolished in MAVS(-/-) cells. NS4A represses RLR-, but not Toll-like receptor-mediated immune responses. NS4A specifically binds the N-terminal caspase activation and recruitment domain (CARD) of MAVS and thus blocks its accessibility by RLRs. Our study provides in-depth understanding of the molecular mechanisms of immune evasion by ZIKV and its pathogenesis

Zika Virus Non-structural Protein 4A Blocks the RLR-MAVS Signaling

Flaviviruses have evolved complex mechanisms to evade the mammalian host immune systems including the RIG-I (retinoic acid-inducible gene I) like receptor (RLR) signaling. Zika virus (ZIKV) is a re-emerging flavivirus that is associated with severe neonatal microcephaly and adult Guillain-Barre syndrome. However, the molecular mechanisms underlying ZIKV pathogenesis remain poorly defined. Here we report that ZIKV non-structural protein 4A (NS4A) impairs the RLR-mitochondrial antiviral-signaling protein (MAVS) interaction and subsequent induction of antiviral immune responses. In human trophoblasts, both RIG-I and melanoma differentiation-associated protein 5 (MDA5) contribute to type I interferon (IFN) induction and control ZIKV replication. Type I IFN induction by ZIKV is almost completely abolished in MAVS-/- cells. NS4A represses RLR-, but not Toll-like receptor-mediated immune responses. NS4A specifically binds the N-terminal caspase activation and recruitment domain (CARD) of MAVS and thus blocks its accessibility by RLRs. Our study provides in-depth understanding of the molecular mechanisms of immune evasion by ZIKV and its pathogenesis

Effects of treatment with Astragalus Membranaceus on function of rat leydig cells

Background Astragalus membranaceus (AM) is a Chinese traditional herb which has been reported to have broad positive effects on many diseases, including hepatitis, heart disease, diabetes and skin disease. AM can promote cell proliferation, increase the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx), and inhibit apoptosis by regulating the transcription of proto-oncogenes controlling cell death. While AM is included in some commercially available “testosterone boosting supplements”, studies directly testing ability of AM to modulate testosterone production are lacking. In the present study, we examined the effects of AM on Leydig cell function in vitro. Methods Rat Leydig cells were purified and treated with AM at different concentrations (0 μg/mL, 10 μg/mL, 20 μg/mL, 50 μg/mL, 100 μg/mL and 150 μg/mL) and cell counting-8 (CCK-8) assay, Enzyme-linked immunosorbent assay, quantitative real time PCR and analysis of activities of SOD and GPx were done respectively. Results Treatment with 100 μg/mL (P \u3c 0.05) and 150 μg/mL AM (P \u3c 0.01) significantly increased Leydig cell numbers. Treatment with AM (20 μg/mL, 50 μg/mL and 100 μg/mL) significantly increased testosterone production (P \u3c 0.01). In addition, increased Leydig cell SOD and GPx activities were observed in response to 20 μg/mL and 50 μg/mL AM treatment (P \u3c 0.01). Furthermore, expression of Bax mRNA was significantly decreased (P \u3c 0.01), and the ratio of Bcl-2/Bax mRNA was significantly increased in response to 20 μg/mL AM in the culture medium (P \u3c 0.05). Conclusions Results supported a beneficial effect of AM on multiple aspects of rat Leydig cell function in vitro including testosterone production

Crystal plane engineering of MAPbI3 in epoxy-based materials for superior gamma-ray shielding performance

The rapid development of the aerospace and nuclear industries is accompanied by increased exposure to high-energy ionising radiation. Thus, the performance of radiation shielding materials needs to be improved to extend the service life of detectors and ensure the safety of personnel. The development of novel lightweight materials with high electron density has therefore become urgent to alleviate radiation risks. In this work, new MAPbI3/epoxy (CH3NH3PbI3/epoxy) composites were prepared via a crystal plane engineering strategy. These composites delivered excellent radiation shielding performance against 59.5 keV gamma rays. A high linear attenuation coefficient (1.887 cm−1) and mass attenuation coefficient (1.352 cm2 g−1) were achieved for a representative MAPbI3/epoxy composite, which was 10 times higher than that of the epoxy. Theoretical calculations indicate that the electron density of MAPbI3/epoxy composites significantly increases when the content ratio of the (110) plane in MAPbI3 increases. As a result, the chances of collision between the incident gamma rays and electrons in the MAPbI3/epoxy composites were enhanced. The present work provides a novel strategy for designing and developing high-efficiency radiation shielding materials