Sky-projected filament spine. The background is the ¹³CO velocity-integrated intensity map. The orange corresponds to the sky-projected spine extracted by CRISPY. The lime ellipses represent dust cores from the ATLASGAL survey. The star markers in different colors represent YSOs at different stages: Class I (red), flat spectrum (yellow), Class II (green), and Class III (blue). The region marked with a red circle is the area of interest to us, where regions 1, 2, and 6 are labeled the same as in the top panel of Fig. 2, and region 7 is an additional region based on the top panel of Fig. 2. Region 7 shows a signal in CO and the Herschel H₂ column density map, but no signal in NH₃. White arrows indicate the positions of the end clumps in G53W and G53E. In G53W, the end clumps are located in regions 1 and 2, while in G53E, the end clumps are found in regions 6 and 7, as clearly depicted in the Herschel H₂ column density map (shown in Figs. 7 and D.1).