Impulsivity and self-control in elementary school children and adult females: Using identical task and procedural parameters

Results of studies examining the relationship between impulsivity and age are limited because different tasks, procedural parameters, and different reinforcers have been used with different aged participants. Thus, the current study sought to rectify these differences in two experiments with children (42, ages 5-12) and adults (69 college-aged females) using the same task with identical procedural parameters. In the Self-Control Video Software Task (SCVST; Forzano and Schunk, 2008; Forzano et al., 2014) participants repeatedly choose between larger, more delayed and smaller, less delayed access to viewing video cartoons. No differences in impulsivity were found between adults and children. No age or gender differences were found among children. Differences in task and procedural parameters are identified as important in their implications for research on impulsivity.

First Report of an Elm Yellows Subgroup 16SrV-C Phytoplasma Infecting Grapevine in Serbia

During a 2002 survey in Serbia, samples of grapevine (Vitis vinifera) were collected from plants showing typical phytoplasma-like symptoms: leaf roll, leaf redness, vein chlorosis and necrosis, and absence of lignification. The material was collected from one viticultural region (Zupa Aleksandrovac), where the disease was recorded in 2000 and showed an increasing percentage of symptomatic plants every year. Total nucleic acid was extracted separately from leaf midveins and stem bark collected from 10 symptomatic and 2 asymptomatic plants. Phytoplasma infection was detected using polymerase chain reaction (PCR) assays with universal primer pair P1/P7 for the amplification of phytoplasma 16S rRNA gene, and primer pair FD9f2/FD9r followed by FD9f3/FD9r2 in nested PCR for specific amplification of the FD9 nonribosomal DNA fragment of the EY-group (1). Phytoplasmas were detected in 9 of 10 midvein extracts from symptomatic grapevines (three of cv. Plovdina, two of cv. Smederevka, and four of cv. Gamé). Also, 6 of 10 bark preparations representing stem collections from the same plants were positive (two samples of cv. Plovdina, both samples of cv. Smederevka, and two samples of cv. Gamé). Both collections of midveins and bark tissues from asymptomatic plants were negative. Fragments amplified with universal P1/P7 primers (16S-23S rDNA) were analyzed by restriction fragment length polymorphism with TruI and TaqI restriction enzymes. The phytoplasmas produced identical restriction profiles to those of 16SrV Elm Yellows group and 16SrV-C Flavescence doreé subgroup (2). To our knowledge, this is the first report of phytoplasma infecting grapevines in Serbia, and the first survey in progress to verify the presence of Scaphoideus titanus to determine if this grapevine yellows could be defined as Flavescence dorée. References: (1) E. Angelini et al. Vitis 40:79, 2001. (2) M. Martini et al. Mol. Cell. Probes 16:197, 2002.