Global PETTS Investigators, Cegielski, J. Peter, Kurbatova, Ekaterina, van der Walt, Martie, Brand, Jeannette, Ershova, Julia, Tupasi, Thelma, Caoili, Janice Campos, Dalton, Tracy, Contreras, Carmen, Yagui, Martin, Bayona, Jaime, Kvasnovsky, Charlotte, Leimane, Vaira, Kuksa, Liga, Chen, Michael P., Via, Laura E., Hwang, Soo Hee, Wolfgang, Melanie, Volchenkov, Grigory V., Somova, Tatiana, Smith, Sarah E., Akksilp, Somsak, Wattanaamornkiet, Wanpen, Kim, Hee Jin, Kim, Chang-ki, Kazennyy, Boris Y., Khorosheva, Tatiana, Kliiman, Kai, Viiklepp, Piret, Jou, Ruwen, Huang, Angela Song-En, Vasilyeva, Irina A., and Demikhova, Olga V.