It is important to study the fine structures of solar filaments with high-resolution observations since it can help us understand the magnetic and thermal structures of the filaments and their dynamics .
In this paper , we study a newly-formed filament located inside the active region NOAA 11762 , which was observed by the 1.6 m New Solar Telescope ( NST ) at Big Bear Solar Observatory ( BBSO ) from 16:40:19 UT to 17:07:58 UT on 2013 June 5 .
As revealed by the H \alpha filtergrams , cool material is seen to be injected into the filament spine with a speed of 5–10 km s ^ { -1 } .
At the source of the injection , brightenings are identified in the chromosphere , which is accompanied by magnetic cancellation in the photosphere , implying the importance of magnetic reconnection in replenishing the filament with plasmas from the lower atmosphere .
Counter-streamings are detected near one endpoint of the filament , with the plane-of-the-sky speed being 7–9 km s ^ { -1 } in the H \alpha red-wing filtergrams and 9–25 km s ^ { -1 } in the blue-wing filtergrams .
The observations are indicative of that this active region filament is supported by a sheared arcade without magnetic dips , and the counter-streamings are due to unidirectional flows with alternative directions , rather than due to the longitudinal oscillations of filament threads as in many other filaments .