Maricruz Manzanarez grabbed tight to weeds and scrub brush growing out from the dirt ridge on one side of the tracks, bracing herself as the train approached, afraid. She worried that the train was going so fast it would suck her in as it went by. She felt its pull on her as it sped past. Caught between the railcars and the ridge, between Mexico and the United States, Manzanarez held on tight. Just a few years ago she had…