Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
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Question: Vaginal microbicides for the prevention of HIV transmission may be an important option for protecting women from infection. Incorporation of dapivirine, a lead candidate nonnucleoside reverse transcriptase inhibitor, into intravaginal rings (IVRs) for sustained mucosal delivery may increase microbicide product adherence and efficacy compared with conventional vaginal formulations. Twenty-four healthy HIV-negative women 18-35 years of age were randomly assigned (1:1:1) to dapivirine matrix IVR, dapivirine reservoir IVR, or placebo IVR. Dapivirine concentrations were measured in plasma and vaginal fluid samples collected at sequential time points over the 33-day study period (28 days of IVR use, 5 days of follow-up). Safety was assessed by pelvic/colposcopic examinations, clinical laboratory tests, and adverse events. Both IVR types were safe and well tolerated with similar adverse events observed in the placebo and dapivirine groups. Dapivirine from both IVR types was successfully distributed throughout the lower genital tract at concentrations over 4 logs greater than the EC50 against wild-type HIV-1 (LAI) in MT4 cells. Maximum concentration (Cmax) and area under the concentration-time curve (AUC) values were significantly higher with the matrix than reservoir IVR. Mean plasma concentrations of dapivirine were <2 ng/mL. These findings suggest that IVR delivery of microbicides is a viable option meriting further study.

Answer: Which infection can be prevented with Dapivirine?


Question: Robert Edward Chambliss (January 14, 1904 -- October 29, 1985), also known as Dynamite Bob, was convicted in 1977 of murder for his role as conspirator in the 16th Street Baptist Church bombing in 1963.

Answer: Which crime led to the conviction of Robert Edward Chambliss?


Question: A star usually is someone who has become famous in sports, film, or pop music, someone like singer Michael Jackson. In the middle nineteen eighties, Michael Jackson successfully made a famous record, which quickly became the most popular recording in the history of music. This made Michael Jackson a bright star. One of the famous sports bright stars in the United States is Mohammed Ali. When he was a young man, he won a gold medal in the Olympic Games as a boxer. Then, he won first place in the world heavy weight boxing match. Before long, he was known as one of the greatest and most famous boxers in sports history. Everyone knows his name. Like the stars in the sky, a bright star will lose his brightness as time passes. He is loved by millions of people today, but will be forgotten tomorrow.

Answer:
What does this passage mainly talk about?


