She spent time in Cuba writing her dissertation on prostitution in the country, which became the topic of her first book, “Prostitution, Modernity, and the Making of the Cuban Republic, 1840-1920.” Sippial had wanted to take a group of students to Cuba for over a decade, but U.S.-Cuban relations were too tense. Since relations between the countries have been improving lately, she was given the green light to plan a study abroad trip.