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Sustained stress triggers series of changes in the brain and the body. At the early stage of stress, the activated hypothalamus-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) axis can upregulate the levels of glucocorticoid (GCs) and catecholamines (CAs), respectively, and then they in turn inhibit the secretion of proinflammatory cytokines directly or indirectly while promoting the secretion of anti-inflammatory cytokines. At the prolonged stage, the sustained activated HPA demonstrates cortisol-resistance. At the same time, the inflammation related transcription pathway, such as nuclear-factor kappa-B (NF-κB) signaling, may be inhibited. Additionally, the inflammatory cytokines mediate a negative feedback regulation on themselves. Collectively, these regulations may increase the proinflammatory cytokines while decreasing the anti-inflammatory cytokines. This may further activate NF-κB and increase the proinflammation cytokines, which in turn reduce the inflammatory responses, contributing to various diseases.

A palaeomagnetic pole position, derived from a precisely dated primary remanence, with minimal uncertainties due to secular variation and structural correction, has been obtained for China’s largest dyke swarm, which trends for about 1000 km in a NNW direction across the North China craton. Positive palaeomagnetic contact tests on two dykes signify that the remanent magnetization is primary and formed during initial cooling of the intrusions. The age of one of these dykes, based on U–Pb dating of primary zircon, is 1769.1 ± 2.5 Ma. The mean palaeomagnetic direction for 19 dykes, after structural correction, is D = 36°, I = − 5°, k = 63, α95 = 4°, yielding a palaeomagnetic pole at Plat=36°N, Plong=247°E, dp = 2°, dm = 4° and a palaeolatitude of 2.6°S. Comparison of this pole position with others of similar age from the Canadian Shield allows a continental reconstruction that is compatible with a more or less unchanged configuration of Laurentia, Siberia and the North China craton since about 1800 Ma

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The 1.27 Ga Mackenzie dyke swarm of the Canadian Shield is a giant radiating dyke swarm that gradually swings in orientation from N‐S in the focal area to NW‐SE trends in peripheral areas. In this paper, we propose a new model (the “Plug” model) that accounts for the paleostress contribution to the mechanism of emplacement for the Mackenzie dyke swarm in the Canadian Shield. The 1.27 Ga stress field on the Canadian Shield calculated by the “Plug” model explains the radiating nature of the Mackenzie dyke swarm around the Coppermine River lava field by local stress concentrations. The parallel nature of the dyke swarm at distance (more than 1000 km) from the focal source can be explained by the existence of a regional tectonic stress field created by ridge push acting on the southeast margin of the Canadian Shield from the Grenville Ocean. The thin elastic plate and two‐dimensional cross‐section modeling suggest that the interaction between stresses from a mantle upwelling and the Grenville Ocean spreading play an important role in the intrusion mechanism of the Mackenzie dyke swarm. The change in dyke orientation from N‐S trending to NW‐SE trending is caused by coupling between resistance from the focal area (Plug area) and a Grenville Ocean ridge push.