What is the fine-grained topic of the following text: Pappano both conducts and plays the piano at the head of the Orchestra and Chorus of the Accademia, while superstar mezzo-soprano Bartoli brings her own special brand of vocal fireworks to add to the festivities. Only return the topic.
Pappano's dual role as conductor and pianist, and Bartoli's vocal performance with the Orchestra and Chorus of the Accademia