Pleated electret HVAC filters are often used in residence to mitigate the particles that originate both indoors and outdoors. These filters are usually tested with particles larger than 300 nm. However, residential particles can contain a significant amount of nanoparticles with size below 50 nm due to cooking, smoking, cleaning, wood burning, and outdoor infiltration. In order to characterize the nanoparticle removal by electret HVAC filters, penetrations of 3-50 nm silver nanoparticles through five different flat sheet electret media used in commercial residential HVAC filters were tested with face velocities of 0.05, 0.5, and 1.0 m s ¡1. Experimental results showed that all media had significantly high penetrations with 0.35-0.8 at the most penetrating particle sizes (MPPSs) for all three velocities, which were in the sizes of 10-30 nm. A model based on single fiber theory for particle penetration predictions was used and compared with the experimental data. Results showed that the model predicted the nanoparticle penetrations very well for all media and all face velocities tested. According to the model, for enhancing the nanoparticle efficiency of the current commercial HVAC filters, the fiber diameter should be reduced or the number of pleats should be increased. However, by doing these, pressure drop and cost may be largely increased. On the other hand, this study found the existing commercial mechanical HVAC filters were much capable for sub-50 nm nanoparticle removal when their minimum efficiency reporting values (MERVs) were larger than 13 and it is concluded mechanical HVAC filters can do a better job than electret ones. However, the quality factor analysis showed electret filters could be regarded as the best filter media for removing particles smaller than 300 nm.

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Adolescence is a critical period for the development of physiological emotion regulatory systems. While stressful life experiences are known to inhibit adaptive regulation, less is known about how parental socialization of emotion regulation may affect this relation. We examined the effect of stressful life experiences on changes in the resting respiratory sinus arrhythmia (RSA) levels of 107 (Mage = 12.84, SD = 0.85) young adolescents over a year, moderated by supportive parental responses to negative emotions. The significant interaction (B = 0.02, p = 0.04) indicated that young adolescents who experienced low levels of supportive parenting in the context of high levels of stressful life experiences showed significant decreases in resting RSA over the year, while adolescents who experienced high levels of supportive parenting showed minimal decreases in RSA. Thus, more supportive parenting significantly compensated for the effect of greater stressful life experiences on changes in resting RSA over time.

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Non-cognitive assessment is used to identify at-risk college students and leverage limited resources to promote academic performance and persistence. Instruments that measure these psychosocial attitudes and skills require self-reported responses and, thus, may be subject to distortion. This study examined the social desirability response bias in a specific non-cognitive assessment tool, the Student Strengths Inventory (SSI), including gender and ethnic differences. Results show that college students did not respond to the SSI in a socially desirable way. Additionally, the SSI subscales contributed to significant variance in the prediction of academic performance and persistence. This study empirically supports the use of non-cognitive assessment in higher education and suggests interventions for using non-cognitive assessment data at the individual, group, and aggregate level.

Marijuana use is pervasive among young adults, and potential marijuana-related impairment may increase as marijuana gains increasing legal status in the United States. However, little is known about the causes and consequences of marijuana use among college students. This study examined the relations between marijuana use frequency and marijuana-related impairment as moderated by religious strength of faith in college students at a Christian university. Results supported study hypotheses—religious strength of faith moderated the relation between marijuana use frequency and marijuana-related impairment, such that individuals with greater religious strength of faith experienced greater marijuana-related impairment. These findings help clarify the nature of the relations between strength of faith and marijuana use and impairment and may inform interventions for problematic marijuana use.

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