Porcellini et al. (A-8) studied 13 HIV-positive patients who were treated with highly active antiretroviral therapy (HAART) for at least 6 months. The CD4 T cell counts (x 10"/1) at baseline for the 13 subjects are listed below. 230 205 313 207 227 245 173 58 103 181 105 301 169 SOURCE: Simona Porcellini, Guiliana Vallanti, Silvia Nozza, Guido Poli, Adriano Lazzarin, Guiseppe Tambussi, Antonio Grassia, "Improved Thymopoietic Potential in Aviremir HIV Infected Individuals with HAART by Intermit tent IL-2 Administration," AIDS, 17 (2008). 16217-1630. Shair and Jasper (A-9) investigated whether decreasing the venous return in young rats would affect ultrasonic vocalizations (USVs). Their research showed no significant change in the number of ultrasonic vocalizations when blood was removed from either the supe- rior vena cava or the carotid artery. Another important variable measured was the heart rate (bmp) during the withdrawal of blood. The table below presents the heart rate of seven rat pups from the experiment involving the carotid artery. 500 570 560 570 450 560 570 SOURCE: Harry N.