The main differences between emitter and collector are doping concentration and size. The emitter is heavily doped, while the collector is lightly doped. You could try to swap them, but you'll get a very low \$H_{FE}\$, probably even less than 1.
Image Credit: Photo: Oxmoor House. SEASON: Although available year-round, eggplant is at its peak from July to October. CHOOSING: When selecting, look for eggplants with firm, glossy skin. Size and color vary widely among types, but the eggplant should feel heavy. Avoid those with wrinkled skin, soft spots, or brown patches.
In the United States, flu season occurs in the fall and winter. The peak of flu season has occurred anywhere from late November through March. The overall health impact (e.g., infections, hospitalizations, and deaths) of a flu season varies from year to year.