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The impact of shield construction on the close lateral passing of high-speed railways can threaten the safety of operating high-speed railways. To study the deformation characteristics of the shield structure after the application of isolation piles from the ground surface and the deformation characteristics of the bridge piers of an overpassing high-speed railway, we analyze the mechanism of isolation pile restraint control and establish a three-dimensional numerical model of a shield structure to study the situation of a high-speed railway with a metro interval under passing a high-speed railway passenger line project. Combined with the measured data and numerical simulation data of the same construction stage, we study the impact of shield structure lateral passing on high-speed railway piers and surrounding ground surface in terms of the disturbance changes and the effect of isolation, as well as the effect of the lateral passing of the shield tunnel on the surface of the bridge piers and the surrounding area and the control effect of the isolation piles on the deformation. The results show that the isolation pile can block the development of the soil layer rupture surface and the stress path. The isolation pile has a good control effect on the vertical displacement of the bridge pier. The vertical displacement of the bridge pier decreases from 0.6 mm to 1.1 mm after the single- and double-track tunneling, and the displacement changes along the depth direction from non-uniform to relatively uniform. The vertical displacement of the ground surface includes both uplift and settlement, which occur at the same time. When the shield tunneling advances, the form of the ground settlement trough is changed from a “V” shape formed by the right single-track tunneling to a “W” shape after the double-track tunneling. The isolation pile can effectively control the influence range of tunnel excavation; its lateral displacement form changes regularly, and the lateral uplift is always in a “double-C outward expansion” shape. The initial excavation greatly disturbs the initial stress field, so it is necessary to pay attention to the control and management of measures to destroy the initial stress field.

Hypertension is among the most harmful factors of cardiovascular and cerebrovascular diseases and poses an urgent problem for the development of human society. In addition to previous studies on its pathogenesis focusing on the peripheral sympathetic nervous system, investigating the central causes of high blood pressure involving the neuroendocrine and neuroinflammatory mechanisms of the hypothalamic paraventricular nucleus (PVN) is paramount. This nucleus is considered to regulate the output of neurohormones and sympathetic nerve activity. In this article, we focussed on the neuroendocrine mechanism, primarily exploring the specific contributions and interactions of various neurons and neuroendocrine hormones, including GABAergic and glutamatergic neurons, nitric oxide, arginine vasopressin, oxytocin, and the renin-angiotensin system. Additionally, the neuroinflammatory mechanism in the PVN was discussed, encompassing microglia, reactive oxygen species, inflammatory factors, and pathways, as well as immune connections between the brain and extracerebral organs. Notably, the two central mechanisms involved in the PVN not only exist independently but also communicate with each other, jointly maintaining the hypertensive state of the body. Furthermore, we introduce well-known molecules and signal transduction pathways within the PVN that can play a regulatory role in the two mechanisms to provide a basis and inspire ideas for further research. [ABSTRACT FROM AUTHOR]

In order to understand the pollution characteristics and health risks of heavy metals in PM2.5 in the atmospheric environment of Yuncheng City, PM2.5 samples were collected in urban, industrial and agricultural areas of Yuncheng City in the autumn and winter of 2018. Mass concentrations of 10 heavy metal elements such as V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd and Pb in samples were analyzed by wet microwave digestion and inductively coupled plasma mass spectrometry, and the distribution characteristics of PM2.5 and pollution characteristics of heavy metal elements were analyzed. Health risk assessments were also made for different populations (adult males, adult females and children). The results showed that the mean values of PM2.5 in urban, industrial and agricultural areas were 116.59, 124.00 and 86.05 µg/m³, respectively. The mass concentrations of PM2.5 in the three areas are 74.29, 78.75 and 46.83 µg/m³ in the non-heating season, and 134.52, 140.54 and 104.21 µg/m³ in the heating season. In the non-heating season, the mass concentrations of 10 kinds heavy metals in urban, industrial and agricultural areas were 0.36 to 132.41, 0.40 to 119.42 and 0.81 to 66.59 ng/m³, respectively. During the heating season, the mass concentrations of 10 kinds heavy metals in urban, industrial and agricultural areas were 0.45 to 278.19, 0.57 to 336.85 and 0.43 to 144.18 ng/m³, respectively. The mass concentration of PM2.5 in heating season is higher than that in non-heating season, and it is the highest in urban area, followed by industrial area and agricultural area. The mass concentration of most heavy metals was higher in the heating season than in the non-heating season. The results of health risk assessment showed that the non-carcinogenic risk of heavy metal pollution in atmospheric PM2.5 in Yuncheng City was small, and the carcinogenic risk was mainly As, Cr, Cd and Co. The ranking of carcinogenic risk for different populations was the highest for adult males, followed by adult females and children were the last. [ABSTRACT FROM AUTHOR]