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The pathogenesis of alopecia areata, a common autoimmune non-scarring alopecia, remains unclear・ Current studies have shown that the loss of immune privilege of hair follicles due to the up-regulation of MHC molecules and the decrease in immunosuppressive molecules leads to the exposure of self-antigens in the affected area・ This triggers the infiltration of immune cells (such as CD8 + T cells, NK cells, plasmacytoma dendritic cells, and mast cells) around the hair bulb ・ Various immune cells and related cytokines participate in the pathogenesis and development of this disease through diverse signaling pathways・ Due to its complex pathogenesis and diverse clinical manifestations, there are challenges in the diagnosis and treatment in clinic・ This paper aims to provide a comprehensive review on recent advances in understanding the immunological pathogenesis of alopecia areata by focusing on mechanisms underlying immune privilege loss around hair follicles and the interaction between various immune cells in the microenvironment for a deeper understanding of its pathogenesis・ It also seeks to explore new research directions and potential treatment strategies. [ABSTRACT FROM AUTHOR]

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Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Emergency water supply is one of the most important lifeline projects for post-disaster survival support. Multi-stage pump can be the core power source for fluid transportation. A stable and reliable operation is crucial to rescue and support at disaster sites. In actual operation, the unexpected shutdown of emergency water supply multi-stage pumps can cause drastic changes in the performance parameters, such as the impeller rotating speed, flow rate, and pressure. The internal flow field in multi-stage pumps can pose a serious threat to the water supply safety. This study aims to investigate the transient response to the internal flow field during the hydraulic transition of multi-stage pump shutdown. A speed prediction was established to numerically calculate the internal flow field of the stage pump, according to the rotation balance equation of the impeller. The transient effects were analyzed from the dynamic characteristics of the impeller rotating speed, outlet flow rate, torque and the flow structures inside each stage of the impeller during the unexpected shutdown. The results indicate that the multi-stage pump shared four conditions during unplanned shutdown, pumping, braking, reversing and runaway. The rotational speed of the impeller showed a trend of first decreasing in the positive direction, and then increasing in the reverse direction, while finally stabilizing around the runaway speed of -4 210 r/min. The flow rate of the pump showed a trend of first positive decrease followed by a reverse increase, then stable reverse decrease and finally stayed around the runaway flow rate of -14.32 kg/s. The torque showed a trend of positive decrease followed by a positive increase, then stable positive decrease and finally stayed near zero. The continuous changes in the magnitude and direction of flow and speed inside the pump were attributed to the flow separation and backflow inside the impeller channel, accompanied by spatiotemporal evolution, such as the formation, development and fragmentation of vortices. The entropy output value was closely related to the unstable flow structure inside the multi-stage pump, while the loss caused by turbulent dissipation played a dominant role. The turbulent dissipation entropy production accounted for about 65.2% after reaching the runaway condition. Energy loss mainly occurred inside the impeller flow channel. There was a significant loss of the internal flow field in the braking condition. There was the most variation in the pressure fluctuation at the monitoring points in the first stage flow channel of the multi-stage pump. The amplitude of the pressure fluctuation coefficient showed a decreasing trend with the increase of the stage number. The dominant frequency of the pressure pulsation amplitude was positively correlated to the rotating speed of the multi-stage pump, corresponding to the blade passage frequency. The amplitude of dominant pressure pulsation frequencies gradually increased along the direction of fluid flow. There was the most significant change in the first stage flow channel during the unexpected shutdown of the multistage pump, which was accompanied by the most complex flow structure. The frequency characteristics of pressure pulsation can reflect the differential changes in flow instability during unexpected shutdowns. The research results can provide theoretical guidance for the safe and stable operation of emergency water supply systems. [ABSTRACT FROM AUTHOR]

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Hydrobiology is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Zhengzhou University: Engineering Science is the property of Editorial Office of Journal of Zhengzhou University: Engineering Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)