Activity-driven swelling and dynamics in segmentally active Rouse chains

We study a segmentally active Rouse chain in which activity is confined to a single contiguous segment of tunable length and position along the contour. Employing analytical normal-mode theory together with Brownian-dynamics simulations, we quantify how localized activity governs conformation and dynamics. Using global conformational measures such as the mean square radius of gyration and end-to-end distance, we observe an unusual swelling pattern: for a fixed length of the active segment, placi