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Metastability and Eye Movements: A Dynamical‑Systems Interpretation

  1. Why metastability is a natural language for gaze behavior The idea that perception, attention, and neural activity evolve through transiently stable states has deep roots in cognitive science and neuroscience. Concepts such as attractors , basins , noise‑induced transitions , and escape times appear in work on perceptual switching, decision‑making, and neural population dynamics (Kelso, 1995; Rabinovich et al., 2008; Deco & Jirsa, 2012). Eye movements, especially the alternation between fixations and saccades ,   fit remarkably well into this metastable picture. The Freidlin–Wentzell theory of rare events (Freidlin & Wentzell, 2012) provides a rigorous mathematical language for these intuitions. 2. Fixations as metastable states  Consider the gaze position X t as the state of a stochastic dynamical system. During a fixation the  gaze remains confined to a small region, microsaccades and noise generate small fluctuations, and the gaze tends to return...

Trend Extraction Across Long Timelines in Noisy Cell‑Culture Experiments

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  A follow‑up to “Cell Count Analysis with cycleTrendR” — focused on neurodegenerative drift In our previous post , we explored how cycleTrendR can be applied to cell‑count trajectories in longitudinal culture experiments. That example sparked an insightful question on LinkedIn : How does cycleTrendR perform when the signal is slow, noisy, and stretched across long timelines — as in neurodegenerative disease models? This post is a direct response. Neurodegenerative phenotypes often evolve gradually, with subtle changes accumulating over weeks or months. Meanwhile, experimental noise — imaging variability, segmentation artefacts, media‑change cycles — fluctuates rapidly and can dominate the signal. cycleTrendR was designed precisely for this challenge: to extract slow biological drift from noisy, irregular, and cyclic time series. How cycleTrendR isolates slow biological drift from fast experimental noise Longitudinal cell‑culture experiments — especially those modelling neurodege...

Cell Count Analysis with cycleTrendR

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  1. Introduction Long‑term monitoring of adherent cell cultures (e.g., Vero, MDCK) is central to vaccine development, viral propagation, and QC workflows in CRO environments. Standard analyses typically focus on short‑term growth metrics such as doubling time, confluence progression, and endpoint viability. While informative, these metrics overlook slow drifts, cyclic environmental influences, and structural transitions that emerge over multi‑day or multi‑week monitoring. Operational routines (e.g., weekly medium changes), environmental oscillations (e.g., daily temperature cycles), and metabolic rhythms can introduce periodic components into cell‑density trajectories. These patterns are rarely analyzed explicitly, despite their potential impact on viral yield, infection kinetics, and batch‑to‑batch reproducibility. This post demonstrates how cycleTrendR can extract long‑term trends, dominant cycles, and structural transitions from a realistically simulated adherent cell‑co...

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