Temporary trade barriers and enterprise export market changes: evidence from China

In theory, previous studies believed that the export market of enterprises was homogeneous. There is no difference in each export market, which is obviously inconsistent with the actual trade situation. This paper divides the export market of enterprises into main export market and secondary export market according to the export status, explores the export changes of enterprises to the main export market and secondary export market respectively when the temporary trade barriers of the main export market to the trade exporting country are raised. This paper focuses on the impact of the main export market on the anti-dumping degree, countervailing level and the improvement of trade safeguard measures on the export conversion of enterprises between the main and secondary markets. The research shows that the increase of the anti-dumping degree of the main market against the trade exporting countries will lead to the higher probability of role exchange between the main and secondary markets; The countervailing level of the main market against the trade exporting countries rises, and the export of enterprises is more likely to turn to the secondary market; The greater the trade safeguard measures in the main market, the more likely the secondary market will become the main marke

The JAK/STAT3 signaling pathway in vaccinia virus infection

Master of ScienceBiochemistry and Molecular BiophysicsZhilong YangPoxvirus infections continue to threaten human health despite the eradication of smallpox, which was one of the most lethal infectious diseases in human history. Our objectives were to identify the host cell components/functions that are important for poxvirus infection and to gain insights into the molecular mechanism of poxvirus replication, ultimately guiding novel anti-viral development. Using vaccinia virus, the prototype poxvirus, we screened inhibitors of viral replication from over 3,000 chemical compounds, most of which have known cellular targets. This screening revealed numerous JAK/STAT3 inhibitors that could inhibit the replication of vaccinia virus. We further used multiple inhibitors of the JAK/STAT3 pathway and tested their effects on the replication of vaccinia virus in multiple primary and transformed cells through reporter assay and viral infectious particles measurement. The JAK/STAT3 inhibitors being tested were: SC144, an inhibitor of the interleukin 6(IL-6), a receptor of the JAK/STAT3 signaling pathway, AZ960 (a JAK2 inhibitor), Stattic and niclosamide (inhibitors of STAT3). Overall, our data indicate the JAK/STAT3 inhibitors could repressed vaccinia virus replication in multiple cell types, suggesting that the JAK/STAT3 signaling pathway is required for the efficient replication of vaccinia virus. Moreover, we observed that STAT3 was enriched in the cell nucleus, although the phosphorylation level of STAT3 was downregulated in vaccinia virus-infected cells during the early stages of infection. This study demonstrates an important role of the JAK/STAT3 signaling pathway in the replication of vaccinia virus, providing a possible novel direction by which to intervene in poxvirus infection and related diseases

High yield expression of an AHL-lactonase from Bacillus sp. B546 in Pichia pastoris and its application to reduce Aeromonas hydrophila mortality in aquaculture

<p>Abstract</p> <p>Background</p> <p><it>Aeromonas hydrophila </it>is a serious pathogen and can cause hemorrhagic septicemia in fish. To control this disease, antibiotics and chemicals are widely used which can consequently result in "superbugs" and chemical accumulation in the food chain. Though vaccine against <it>A. hydrophila </it>is available, its use is limited due to multiple serotypes of this pathogen and problems of safety and efficacy. Another problem with vaccination is the ability to apply it to small fish especially in high numbers. In this study, we tried a new way to attenuate the <it>A. hydrophila </it>infection by using a quorum quenching strategy with a recombinant AHL-lactonase expressed in <it>Pichia pastoris</it>.</p> <p>Results</p> <p>The AHL-lactonase (AiiA_B546) from <it>Bacillus </it>sp. B546 was produced extracellularly in <it>P. pastoris </it>with a yield of 3,558.4 ± 81.3 U/mL in a 3.7-L fermenter when using 3-oxo-C8-HSL as the substrate. After purification with a HiTrap Q Sepharose column, the recombinant homogenous protein showed a band of 33.6 kDa on SDS-PAGE, higher than the calculated molecular mass (28.14 kDa). Deglycosylation of AiiA_B546with Endo H confirmed the occurrence of <it>N</it>-glycosylation. The purified recombinant AiiA_B546showed optimal activity at pH 8.0 and 20°C, exhibited excellent stability at pH 8.0-12.0 and thermal stability at 70°C, was firstly confirmed to be significantly protease-resistant, and had wide substrate specificity. In application test, when co-injected with A. <it>hydrophila </it>in common carp, recombinant AiiA_B546decreased the mortality rate and delayed the mortality time of fish.</p> <p>Conclusions</p> <p>Our results not only indicate the possibility of mass-production of AHL-lactonase at low cost, but also open up a promising foreground of application of AHL-lactonase in fish to control <it>A. hydrophila </it>disease by regulating its virulence. To our knowledge, this is the first report on heterologous expression of AHL-lactonase in <it>P. pastoris </it>and attenuating <it>A. hydrophila </it>virulence by co-injection with AHL-lactonase.</p

Assessment of English Teaching From Social - Anthropological Perspective: A Case Study of Microteaching in Warwick SJTU ETD Programme

Microteaching has gained considerable attention for its effectiveness in training teachers. Based on social-anthropological theory, a microteaching workshop in Warwick SJTU ETD Programme for 22 English teachers was investigated. Observation and interview, as the main basic methods, were applied to collect data. The results showed that microteaching offered participants an opportunity to practice teaching and receive useful feedback from peers and professional supervisors. Moreover, it was indicated that the improvement of teaching largely depends on self-reflection. The participants who were aware of teaching objectives and teaching aids, and opened to alternative teaching materials could easily manage the classroom teaching, and activate students’ learning

DBS: Dynamic Batch Size For Distributed Deep Neural Network Training

Synchronous strategies with data parallelism, such as the Synchronous StochasticGradient Descent (S-SGD) and the model averaging methods, are widely utilizedin distributed training of Deep Neural Networks (DNNs), largely owing to itseasy implementation yet promising performance. Particularly, each worker ofthe cluster hosts a copy of the DNN and an evenly divided share of the datasetwith the fixed mini-batch size, to keep the training of DNNs convergence. In thestrategies, the workers with different computational capability, need to wait foreach other because of the synchronization and delays in network transmission,which will inevitably result in the high-performance workers wasting computation.Consequently, the utilization of the cluster is relatively low. To alleviate thisissue, we propose the Dynamic Batch Size (DBS) strategy for the distributedtraining of DNNs. Specifically, the performance of each worker is evaluatedfirst based on the fact in the previous epoch, and then the batch size and datasetpartition are dynamically adjusted in consideration of the current performanceof the worker, thereby improving the utilization of the cluster. To verify theeffectiveness of the proposed strategy, extensive experiments have been conducted,and the experimental results indicate that the proposed strategy can fully utilizethe performance of the cluster, reduce the training time, and have good robustnesswith disturbance by irrelevant tasks. Furthermore, rigorous theoretical analysis hasalso been provided to prove the convergence of the proposed strategy.Comment: The latest version of this article has been accepted by IEEE TETC