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Insulation is considered the weakest link in electrical equipment. The combined effects of special working conditions in coal mines and aging factors such as electrical, thermal, and mechanical stresses make it difficult to determine the aging mechanism and evaluate the condition of EPDM insulation for high-voltage cables used in mines. This paper introduces the basic performance and aging factor types of EPDM insulation for high-voltage mobile flexible cables used in coal mines. Based on the physical, chemical, mechanical, and electrical properties of EPDM under the influence of multiple aging factors, the aging mechanism of EPDM is proposed. This paper summarizes the basic principles and existing problems of online monitoring methods for insulation resistance, partial discharge, dielectric loss factor, and temperature of mining high-voltage cables. The paper summarizes the current research status of insulation status evaluation methods for mining high-voltage cables. The paper introduces the evaluation methods for insulation status of multi parameter based on improved radar map and single parameter based on dielectric loss mining high-voltage cables. To cope with the development of coal mine intelligence, on the one hand, it is suggested to do research on intelligent perception and control of mining electrical equipment to compensate for the lack of state perception and state evaluation feature quantities. On the other hand, it is necessary to study lightweight models or algorithms to reduce the computational complexity, parameter quantity, and analysis time of intelligent terminals near devices. It improves the feasibility of state evaluation technology, and lays the foundation for achieving intelligent analysis and decision-making.

This article meticulously examines the interplay of myth and memory in Kenzaburō Ōe's novel Death by Water, with a central focus on the protagonist's relentless investigation into his father's death by drowning. Ōe skillfully intertwines personal tragedy with the collective consciousness of Japan, invoking the 'Meiji Spirit' and the 'Spirit of Postwar Democracy' to frame the narrative. The study identifies the 'drowning death' as a mythological archetype, analyzing its symbolic representation of life, death, and rebirth cycles within the novel's context. Through a close reading of the characters' experiences, particularly the deaths of the father and Daio, the paper explores the multifaceted nature of mythical thinking shaped by historical zeitgeists. The findings suggest that national spirit, or Zeitgeist, exerts a profound influence on societal values and actions, leading to a discourse on the nation's relationship with the concepts of sacrifice and offering. Employing political mythology, the study delves into the nuanced connection between national identity and the sacrificial ethos, proposing that such narratives reflect deeper cultural and political undercurrents. [ABSTRACT FROM AUTHOR]

Acne is a common chronic inflammatory disorder of the sebaceous gland in the hair follicle. Commonly used external medications cause skin irritation, and the transdermal capacity is weak, making it difficult to penetrate the cuticle skin barrier. Hair follicles can aid in the breakdown of this barrier. As nanomaterials progress, polymer-based nanocarriers are routinely used for hair follicle drug delivery to treat acne and other skin issues. Based on the physiological and anatomical characteristics of hair follicles, this paper discusses factors affecting hair follicle delivery by polymer nanocarriers, summarizes the common combination technology to improve the targeting of hair follicles by carriers, and finally reviews the most recent research progress of different polymer nanodrug-delivery systems for the treatment of acne by targeting hair follicles.

Air mass concentration data from 8 environmental quality monitoring sites and meteorological data of Chengdu from 1 December 2013 to 28 February 2014 were used in this study. Chengdu suffered five continuous heavy pollutions during this winter due to the basin terrain and the meteorological conditions of low wind speed, low precipitation and high relative humidity. Analysing the hourly resolution time series of pollutants' concentrations, variation of PM 2.5 in the urban area followed a growing "saw-tooth cycle" pattern during the heavy pollution, with a daily cycle of bimodal distribution. The massive letting-off of fireworks within a short period of time on the Eve of the Lunar New Year under the unfavourable diffusion conditions resulted in an extreme pollution event. The sharply rising Longmen-Qionglai Mountains to the west of the Sichuan Basin not only acted as a huge barrier to block the air mass from the east but also favoured the formation of a local circulation. The cluster analysis of back trajectories revealed that up to 77% of them came from the inner part of the Basin. Combining the concentration data of PM 2.5 with air mass back trajectories, a potential source contribution function (PSCF) model and a concentration-weighted trajectory (CWT) method were used to evaluate the transport pathways and sources over PM 2.5 of Chengdu, revealing that the main potential sources of PM 2.5 were located in southeast cities and the western margin of the Sichuan Basin. The result provided advice for the government to take measures in improving air quality., (Copyright © 2017 Elsevier B.V. All rights reserved.)