Five science fiction stories about Mexicans and AmericansLA RUBIA How far will Francisca go to protect her colony of Mexican refugees from pirates roving the asteroid belt? PASE DE UN DÍAChalo could teleport to the U.S. every day and work for a better life for his family-if he kept his day pass. MIKE FINK GOES TO BIG BENDCharacters from American, Mexican, and Native folklore meet in west Texas in the 21st century. THE THIRTIETH AMENDMENTGonzalo had to pass the test of English fluency to prove himself a U.S. citizen. So did others willing to cheat. AFFECTIVE DISORDERTexas PI Albert Jimenez found more than the usual when he investigated an heiress' "suicide.