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Geomagnetically induced currents (GICs) are one of the main manifestations through which space weather affects human technical facilities, and GICs constitute the final link in the solar wind‐magnetosphere‐ionosphere‐ground interaction chain. Therefore, understanding the responses of power grids to solar superstorms is crucial for space weather research and emergency preparedness purposes. In this work, we combine the Space Weather Modeling Framework with a ground conductivity model and a model of the Chinese Guangdong 500 kV power grid to investigate the response of the whole power grid if the 23 July 2012 solar superstorm had struck the Earth. The maximum |GICs| produced in the power grid by this event reach approximately 400 A, which is more than thrice those measured during a strong magnetic storm with Kp = 8. Based on statistical analyses of the strength and duration of large GICs at 54 substations and a comparison with the GICs responsible for the Hydro‐Québec power outage on 13 March 1989, we stipulate that the risk of GICs in the Guangdong 500 kV power grid is very high. The simulation results also reveal that field‐aligned currents can play an important role in producing GICs in middle‐ and low‐latitude power grids during solar superstorms. This finding provides crucial insight for understanding the factors that generate strong GICs at middle and low latitudes. Plain Language Summary: The Sun is not a particularly peaceful entity, it can abruptly launch powerful radiation and plasma into space. If such a coronal mass ejection (also called a solar storm) struck the Earth, there would be serious consequences for humanity. Specifically, solar storms can generate geomagnetically induced currents (GICs) in high‐voltage power transmission systems, which can damage transformers and even cause the whole system to collapse. How would a power grid respond to an extreme solar storm? Furthermore, how strong can the associated GICs be, and how serious are the consequences? To address these uncertainties, we built a model of the corresponding interaction chain based on physical principles. The model was driven by the solar wind conditions of a solar superstorm that occurred on 23 July 2012 and was observed by a satellite. We showed that even a low‐latitude power grid may collapse under the impact of a solar superstorm. Consequently, without sufficient preparation, the consequences of a solar superstorm for power grids worldwide could be devastating. Key Points: We built a model to simulate geomagnetically induced currents (GICs) in a power grid in China during a solar superstormGICs can reach hundreds of amperes in a low‐latitude power network during a solar superstormField‐aligned currents play an important role in producing GICs within low‐latitude power networks during solar superstorms [ABSTRACT FROM AUTHOR]

Human tumour necrosis factor α ( hTNF α) has been proved to be a validated therapeutic target in a number of immune-mediated inflammatory diseases ( IMIDs). Fully human monoclonal antibodies ( mAbs) that can neutralize soluble hTNF α ( sTNF α) as well as transmembrane hTNF α (tm TNF α) are more desirable hTNF α antagonists. Here, we report that novel anti- hTNF α human low-molecular-weight MAbs have been selected and identified using both sTNF α and tm TNF α as target antigens by the combination of ribosome display and E. coli expression system for the first time. As a newly born engineering small molecular antibody, three-domain antibody fragment ( VH/ κ) provides an alternative promising molecular principle to generate biological agents for TNF α-dependent IMIDs. In this study, a panel of novel human VH/κs (F09, F21, F49 and F409) with high affinity (10−10-10−9 mol/l) to neutralize sTNF α as well as tm TNF α was generated by the combination of ribosome display and E. coli expression system. Among the four clones, F21 and F409 could reduce cytotoxicity on L929 cells induced by sTNF α as well as tm TNF α effectively, and both of them had great potential to inhibit hTNF α-mediated NF- κB activation. Soluble F21 and F409 were also able to inhibit the binding of hTNF α to TNFR1 and TNFR2. The new human antibodies described here have desirable capability to neutralize sTNF α as well as tm TNF α effectively with high affinity and reasonable stability; this may provide an alternative approach for patients who are not responding adequately to currently available anti-TNF α agents. [ABSTRACT FROM AUTHOR]

Interleukin-22 ( IL-22) and IL-22-producing T helper ( Th) cells are involved in the pathogenesis of autoimmune diseases. However, the roles of IL-22 and IL-22-producing T helper cells in systemic lupus erythematosus ( SLE) remain unclear. Plasma levels of IL-22 were measured in 41 patients with SLE (19 new-onset and 22 relapsing patients) and 20 healthy controls by enzyme-linked immunosorbent assay ( ELISA). Meanwhile, the percentages of CD4+ IFN- γ+ (Th1), CD4+ IL-17+ (Th17) and CD4+ IFN- γ− IL-17− IL-22+ ( Th22) cells in peripheral lymphocytes were determined by flow cytometry, and plasma IL-22 autoantibodies were detected by ELISA in 19 new-onset SLE patients and 20 healthy controls. Plasma IL-22 levels in new-onset SLE patients were significantly decreased compared with relapsing SLE patients and healthy controls. After treatment with prednisone and hydroxychloroquine, the levels of plasma IL-22 in new-onset SLE patients were obviously increased but still lower than healthy controls. There was a positive correlation between plasma IL-22 levels and the percentages of Th22 cells, but not Th1 and Th17 cells. Moreover, plasma IL-22 levels as well as peripheral Th17 and Th22 cells correlated with SLE disease activity index ( SLEDAI) scores and erythrocyte sedimentation rate ( ESR). High frequencies of plasma IL-22 autoantibodies were detected in new-onset SLE patients. However, IL-22 levels did not correlate with IL-22 autoantibody. Decreased plasma IL-22 levels and correlation with Th22 cells may be distinct features in new-onset SLE. Moreover, IL-22 and Th22 cell correlated with SLE disease activity. [ABSTRACT FROM AUTHOR]

Aims This study aimed to assess possible interactive effects of coping styles and psychological stress on depression and anxiety symptoms in Chinese patients with Type 2 diabetes. Methods Three hundred and four patients with Type 2 diabetes underwent a face-to-face interview by trained research staff according to a standardized questionnaire including information on socio-demographic characteristics, psychological stress, coping styles and anxiety and depressive symptoms. The interactive effects of coping styles and psychological stress on depression and anxiety symptoms were assessed by hierarchical multiple regression analyses. Results There were significant associations of the four domains of psychological stress with anxiety and depressive symptoms, except for the relationship between ‘reduced economic condition’ and depressive symptoms. ‘Negative coping style’ significantly increased the level of both anxiety and depressive symptoms; whereas, ‘active coping style’ and ‘avoidant coping style’ decreased the risk of depressive symptoms. The interactions of ‘negative coping style’ with ‘worrying about decline in body/physical function’ and ‘reduced economic condition’ significantly increased the risk of anxiety and depressive symptoms, and the interaction of ‘social/family crisis caused by the disease’ with ‘avoidance coping style’ and ‘worrying about decline in body/physical function’ with ‘active coping style’ significantly decreased the risk of depressive symptoms. Conclusions The results of this study suggest that certain coping styles might moderate the association of psychological stress with anxiety and depressive symptoms in Chinese patients with Type 2 diabetes. [ABSTRACT FROM AUTHOR]

Peanut (Arachis hypogaea L.) plants (cvs Florunner and Pronto) were inoculated at the two-leaf stage with peanut mottle virus (PMV) to obtain PMV-infected plants. Shoot-tips from plants grown in the glasshouse (27 °C) or from plants maintained at 35 °C were used for tip culture. In some experiments ribavirin was added to the culture medium at 5 mg/1, 10 mg/1, 15 mg/1 or 20 mg/1. Plants regenerated from meristems or shoot-tips taken from virus-infected plants were not virus-free. After 45 days at 35 °C, foliar tissue of 93 % of Florunner and 95 % of Pronto plants tested negative for PMV by enzyme-linked immunosorbent assay (ELISA). When shoot-tips from the plants that tested negative by ELISA were used for tip culture, no virus-free plants were obtained. No virus-free plants were obtained from tips cultured on medium supplemented with ribavirin. However, when tip culture, thermotherapy and chemotherapy were combined; 80 % of Florunner and 100 % of Pronto plants were found negative for PMV. [ABSTRACT FROM AUTHOR]

The article presents an abstract of the study "Coupling of Gaba Biosynthesis and Gaba Packaging in Synaptic Vesicles." The study will be presented at a joint meeting of the International Society for Neurochemistry and the European Society for Neurochemistry which will be organized in Berlin, Germany, from August 8-14, 1999. The result suggests that the membrane associated glutamic acid decarboxylase is greatly activated by adenosine triphosphate (ATP), whereas non-hydrolyzable ATP analog has no effect.