Ultrafast Amplification of DNA on Plastic Microdevices for Forensic Short Tandem Repeat Analysis

The majority of microfluidic devices used as a platform for low‐cost, rapid DNA analysis are glass devices; however, microchip fabrication in glass is costly and laborious, enhancing the interest in polymeric substrates, such as poly (methyl methacrylate) (PMMA), as an inexpensive alternative. Here, we report amplification in PMMA polymerase chain reaction (PCR) microchips providing full short tandem repeat profiles (16 of 16 loci) in 30–40 min, with peak height ratios and stutter percentages that meet literature threshold requirements. In addition, partial profiles (15 of 16 loci) were generated using an ultrafast PCR method in 17.1 min, representing a ~10‐fold reduction in reaction time as compared to current amplification methods. Finally, a multichamber device was demonstrated to simultaneously amplify one positive, one negative, and five individual samples in 39 min. Although there were instances of loci dropout, this device represents a first step toward a microfluidic system capable of amplifying more than one sample simultaneously.     

An Investigation of Personality Traits in Relation to Adolescent School Absenteeism

We examined the Big Five personality traits of Agreeableness, Conscientiousness, Emotional Stability, Extraversion, and Openness, as well as four narrower traits of Aggression, Optimism, Tough-Mindedness, and Work Drive in relation to absences from school for middle- and high-school students. Participants were 248 seventh grade students, 321 tenth grade students, and 282 twelfth grade students. Most of the Big Five absence correlations were significant in the expected direction at all 3 grade levels. While Aggression, Optimism, Work Drive were significantly related to absences, only Work Drive added incremental variance to the prediction of absences beyond the Big Five traits. Study results were generally similar across grade levels. Findings were discussed in terms of dispositional absenteeism, the generalizability of the Big Five trait model, and the utility of more narrowband traits. Implications were drawn for early identification of absence-prone students and the precedent role of personality variables in school absence research on the effects of other variables, programs, and interventions.