Just my 2 cents here, but the "swell" you speak of in the strings is a minor 2nd trill (fast alternating notes a semitone apart), and in terms of notes, what I'm hearing is an ascending scale in a minor key (seems like E relative minor, meaning you start on E and end on E, but use notes in G major, having only F#).
Among the textures, what I perceive is a harp glissando on the left, a flute (or perhaps piccolo) playing the scale legato in the middle, and probably some violas playing legato on the right (ending on a perfect fifth below the flute)