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Treatment Options for Chemical Sensitivity
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 5, 2017
William J. Rea, Kalpana D. Patel
The prevailing model of the circadian clock involves the transcription–translation feedback loop, but less is known concerning nontranscriptional mechanisms that may generate circadian oscillations. In cyanobacteria, cycles of protein phosphorylation are sufficient to generate biological rhythms in the absence of transcription.73 In the mammalian SCN, changes in cyclic AMP levels alter period length, an additional example of posttranslational signaling as a mechanism controlling circadian cycles,74 and recent work has shown that the SCN neuronal coupling network itself has intrinsic oscillatory function that can emerge in the absence of cell autonomous oscillators.75 RNAi screening of mammalian cells also indicates coupling of the peripheral clock to PI-3 kinase signaling.76
Stochastic synchronisation of nonlinear networks with additive measurement noise
Published in International Journal of Systems Science, 2023
Junwei Wang, Qijun Ren, Chuance Yan, Kairui Chen
The model of each node is described by a biologically meaningful mathematical model for mammalian circadian oscillations (Soest et al., 2020) with where , , , and . The state variables , , and represent the concentration of clock proteins BMAL1, REV, DBP and PER-CRY, respectively. This model consists of two negative feedback loops (the BMAL1-PER:CRY loop and the BMAL1-REVERB loop), which can help us identify key interlocked transcription/translation feedback loops for generating nonlinear phenomena in the cellular circadian clock without external forcing. With parameters , , , , , , and , , such a model can display circadian oscillations. Moreover, it can be verified that Assumption 2.1 for the nonlinear function holds with the Lipschitz constant .