Use of portable air purifiers as local exhaust ventilation during COVID-19.

The purpose of this study was to determine if strategic placement of portable air purifiers would improve effectiveness of aerosol reduction in a space as compared to use as a general room air purifier. Two sizes of portable air purifiers were placed in two different positions intended to function similar to either a local exhaust ventilation hood or an air curtain to determine if strategic placement would lead to a reduction of particles in a worker's position at a desk in an office environment. Particle generators were used to introduce particulate into the air and personal aerosol monitors measured particles during each test condition. Results showed that when the medium room portable air purifiers used in this study were set to high, corresponding to 98 CFM, and placed near the breathing zone of each office worker with the unit's filter cover removed, the particle concentration was reduced 35% beyond the reduction that would be expected if the same units were placed on the floor behind the occupant's workstation. Results also indicated that the larger portable air purifier tested, positioned as close as reasonable to each occupant's breathing zone with the largest capture area possible (i.e., removing the unit's filter cover), delivers the best aerosol reduction performance. The authors concluded that as a layer of protection against transmission of airborne infectious organisms for office occupants, installing a portable air purifier, sized and operated similar to the units tested in this study on the desk 12 inches from the breathing zone of the worker, has the potential to reduce airborne particulate to a greater degree than if the same units were placed outside of the breathing zone, in the general cubicle area.

Stress and parenting predict changes in adolescent respiratory sinus arrhythmia.

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.

Respiratory sinus arrhythmia and adaptive emotion regulation as predictors of nonsuicidal self-injury in young adults.

Research suggests that both respiratory sinus arrhythmia (RSA) and emotion regulation are related to maladaptive outcomes. However, little is known about how these factors jointly contribute to nonsuicidal self-injury (NSSI). We examined how resting RSA and RSA withdrawal to stress predicted NSSI among young adults, and whether adaptive emotion regulation strategies moderated this effect. We examined this relation in a sample of 70 young adults (Mage = 19.25, SDage = 0.92, 94% female), 35 with a recent history of NSSI and 35 who had never engaged in NSSI. Participants completed a baseline questionnaire and lab visit where physiological responses to a social stressor were collected. Results indicated that resting RSA did not predict recent NSSI engagement. However, greater RSA withdrawal to social stress significantly predicted recent NSSI (ß = 1.35 [0.57], Wald χ2 = 5.52 p = 0.02). Further, problem-solving moderated the relation between RSA withdrawal and recent NSSI such that individuals with greater levels of RSA withdrawal were significantly more likely to engage in NSSI if they also reported low problem-solving (ß = -1.44 [0.64], Wald χ2 = 5.16, p = 0.02). In contrast, the effect of greater RSA withdrawal on NSSI was buffered by high problem-solving. Cognitive reappraisal did not moderate the relation between RSA withdrawal and NSSI. These findings suggest that problem-solving may be an important moderator in the relation between physiological reactivity and NSSI. Interventions should help clients with poor self-regulation develop adaptive problem-solving strategies.