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The Southern Oxidant and Aerosol Study (SOAS) was a large field campaign during June-July 2013 in the southeast USA (Hidy et al., 2014; Hu et al., 2015; Carlton et al., 2018). Vast forested areas emitting large amounts of organic compounds and proximity to metropolitan areas present an ideal environment to investigate the influence of anthropogenic emissions on the biogenic secondary organic aerosol (SOA) formation. The main site of this study, located in rural Centreville, AL, was equipped with a wide variety of state-of-the-art analytical instruments. This project focuses on the source apportionment of the organic carbon (OC) fraction of ambient aerosol samples, through combination of radiocarbon (14C) data with positive matrix factorization information from online aerosol mass spectrometry measurements (AMS-PMF). Analysis of the long-lived radioactive isotope 14C is a unique source apportionment tool: it unambiguously separates fossil from non-fossil sources, as 14C has completely decayed in fossil fuels, whereas modern materials have the contemporary radiocarbon level (Szidat, 2009). 14C was measured for total carbon (TC) and elemental carbon (EC) (Zhang et al., 2012) from quartz filters that were collected at Centreville with daily resolution. This allowed the apportionment of fossil vs. non-fossil sources for EC and OC. Although OC mainly originated from non-fossil sources, a certain fraction was attributed to emissions from fossil sources. These results were compared with AMS-PMF data from a high-resolution time-of-flight AMS (Hu et al., 2015), which identified six different factors, i.e. biomass burning organic aerosol (BBOA), SOA formed through direct condensation of low-volatility oxidation products from isoprene (ISOPOOH-SOA), isoprene epoxydiols-derived SOA (IEPOX-SOA), low-oxidized oxygenated organic aerosol I, attributed to mostly biogenic sources (LO OOAI), low-oxidized OOA II, attributed mostly to anthropogenic sources (LO-OOAII) and more-oxidized OOA (MO-OOA). On average, the less well-understood fractions LO-OOAI, LO-OOAII and MO-OOA comprise ~3/4 of the total organic aerosol mass. 14C analysis of EC enables the distinction of sources of this carbonaceous aerosol fraction between fossil-fuel combustion (mainly from traffic) and biomass burning. It indicated a larger contribution from biomass burning compared to other source apportionment techniques or results from bottom-up emission inventories. The combination of 14C and AMS-PMF analysis provides the potential to apportion fossil vs. non-fossil sources for components for which the non-fossil fraction cannot by analyzed directly, such as SOA (Zotter et al., 2014). In this work, we present such results for the SOAS campaign based on Markov chain Monte Carlo calculations to gain more insight into the sources of SOA precursors. LO-OOAI, LO-OOAII and MO-OOA reveal different contributions of fossil and non-fossil sources, which allows a better understanding of these AMS-PMF factors. Carlton, A. M., et al. (2018), Bull. Am. Met. Soc., in press. Hidy, G. M., et al. (2014), Atmos. Chem. Phys., 14, 11893-11914. Hu, W. W., et al. (2015), Atmos. Chem. Phys., 15, 11807-11833. Szidat, S. (2009), Chimia, 63, 157-161. Zhang, Y. L., et al., (2012) Atmos. Chem. Phys., 12 (22), 10841-10856. Zotter, P., et al. (2014), J. Geophys. Res. Atmos., 119, 6818–6835.

© Copyright 2016 by the American Academy of Pediatrics. This document is copyrighted and is property of the American Academy of Pediatrics and its Board of Directors. All authors have fi led confl ict of interest statements with the American Academy of Pediatrics. Any confl icts have been resolved through a process approved by the Board of Directors. The American Academy of Pediatrics has neither solicited nor accepted any commercial involvement in the development of the content of this publication. Clinical reports from the American Academy of Pediatrics benefi t from expertise and resources of liaisons and internal (AAP) and external reviewers. However, clinical reports from the American Academy of Pediatrics may not refl ect the views of the liaisons or the organizations or government agencies that they represent. The guidance in this report does not indicate an exclusive course of treatment or serve as a standard of medical care. Variations, taking into account individual circumstances, may be appropriate. All clinical reports from the American Academy of Pediatrics automatically expire 5 years after publication unless reaffi rmed, revised, or retired at or before that time.

© Copyright 2016 by the American Academy of Pediatrics. The number of children and adolescents seen in emergency departments (EDs) and primary care settings for mental health problems has skyrocketed in recent years, with up to 23% of patients in both settings having diagnosable mental health conditions. 1 -4 Even when a mental health problem is not the focus of an ED or primary care visit, mental health conditions, both known and occult, may challenge the treating clinician and complicate the patient's care.4 Although the American Academy of Pediatrics (AAP) has published a policy statement on mental health competencies and a Mental Health Toolkit for pediatric primary care providers, no such guidelines or resources exist for clinicians who care for pediatric mental health emergencies. 5, 6 Many ED and primary care physicians report paucity of training and lack of confidence in caring for pediatric psychiatry patients. The 2 clinical reports support the 2006 joint policy statement of the AAP and the American College of Emergency Physicians on pediatric mental health emergencies, 7 with the goal of addressing the knowledge gaps in this area. Although written primarily from the perspective of ED clinicians, it is intended for all clinicians who care for children and adolescents with acute mental health and behavioral problems. They are organized around the common clinical challenges pediatric caregivers face, both when a child or adolescent presents with a psychiatric chief complaint or emergency (part I) and when a mental health condition may be an unclear or complicating factor in a non-mental health ED presentation (part II). Part I of the clinical reports includes discussions of Medical Clearance of Pediatric Psychiatric Patients, Suicide and Suicidal Ideation, Restraint of the Agitated Patient Including Verbal, Chemical, and Physical Restraint, and Coordination of Care With the Medical Home, and it can be accessed online at www.pediatrics.org/cgi/doi/10.1542/peds. 2016-1570. This executive summary is an overview of part II of the clinical reports. Full text of the following topics can be accessed online at www.pediatrics.org/cgi/doi/10.1542/peds. 2016-1573.

© Copyright 2016 by the American Academy of Pediatrics. The number of children and adolescents seen in emergency departments (EDs) and primary care settings for mental health problems has skyrocketed in recent years, with up to 23% of patients in both settings having diagnosable mental health conditions. 1 -4 Even when a mental health problem is not the focus of an ED or primary care visit, mental health conditions, both known and occult, may challenge the treating clinician and complicate the patient's care.4 Although the American Academy of Pediatrics has published a policy statement on mental health competencies and a Mental Health Toolkit for pediatric primary care providers, no such guidelines or resources exist for clinicians who care for pediatric mental health emergencies. 5, 6 Many ED and primary care physicians report a paucity of training and lack of confidence in caring for pediatric psychiatry patients. The 2 clinical reports (www.pediatrics.org/cgi/doi/10.1542/peds. 2016-1570 and www.pediatrics.org/cgi/doi/10.1542/peds. 2016-1573) support the 2006 joint policy statement of the American Academy of Pediatrics and the American College of Emergency Physicians on pediatric mental health emergencies, 7 with the goal of addressing the knowledge gaps in this area. Although written primarily from the perspective of ED clinicians, they are intended for all clinicians who care for children and adolescents with acute mental health and behavioral problems. The clinical reports are organized around the common clinical challenges pediatric caregivers face, both when a child or adolescent presents with a psychiatric chief complaint or emergency (part I) and also when a mental health condition may be an unclear or complicating factor in a non-mental health clinical presentation (part II). Part II of the clinical reports (www.pediatrics.org/cgi/doi/10.1542/peds. 2016-1573) includes discussions of somatic symptom and related disorders, adverse effects of psychiatric medications including neuroleptic malignant syndrome and serotonin syndrome, caring for children with special needs such as autism and developmental disorders, and mental health screening. This executive summary is an overview of part I of the clinical reports. The full text of the below topics can be accessed online at (www.pediatrics.org/cgi/doi/10.1542/peds. 2016-1570). Key considerations are shown in the following sections.

Gas- and aerosol-phase measurements of oxidants, biogenic volatile organic compounds (BVOCs) and organic nitrates made during the Southern Oxidant and Aerosol Study (SOAS campaign, Summer 2013) in central Alabama show that a nitrate radical (NO₃) reaction with monoterpenes leads to significant secondary aerosol formation. Cumulative losses of NO₃ to terpenes are correlated with increase in gasand aerosol-organic nitrate concentrations made during the campaign. Correlation of NO₃ radical consumption to organic nitrate aerosol formation as measured by aerosol mass spectrometry and thermal dissociation laser-induced fluorescence suggests a molar yield of aerosol-phase monoterpene nitrates of 23–44 %. Compounds observed via chemical ionization mass spectrometry (CIMS) are correlated to predicted nitrate loss to BVOCs and show C₁₀H₁₇NO₅, likely a hydroperoxy nitrate, is a major nitrate-oxidized terpene product being incorporated into aerosols. The comparable isoprene product C₅H₉NO₅ was observed to contribute less than 1% of the total organic nitrate in the aerosol phase and correlations show that it is principally a gas-phase product from nitrate oxidation of isoprene. Organic nitrates comprise between 30 and 45% of the NOy budget during SOAS. Inorganic nitrates were also monitored and showed that during incidents of increased coarse-mode mineral dust, HNO₃ uptake produced nitrate aerosol mass loading at a rate comparable to that of organic nitrate produced via NO₃ CBVOCs.

Inorganic aerosol composition was measured in the southeastern United States, a region that exhibits high aerosol mass loading during the summer, as part of the 2013 Southern Oxidant and Aerosol Study (SOAS) campaign. Measurements using a Monitor for AeRosols and GAses (MARGA) revealed two periods of high aerosol nitrate (NO3−) concentrations during the campaign. These periods of high nitrate were correlated with increased concentrations of supermicron crustal and sea spray aerosol species, particularly Na+ and Ca2+, and with a shift towards aerosol with larger (1 to 2.5 μm) diameters. We suggest this nitrate aerosol forms by multiphase reactions of HNO3 and particles, reactions that are facilitated by transport of crustal dust and sea spray aerosol from a source within the United States. The observed high aerosol acidity prevents the formation of NH4NO3, the inorganic nitrogen species often dominant in fine-mode aerosol at higher pH. Calculation of the rate of the heterogeneous uptake of HNO3 on mineral aerosol supports the conclusion that aerosol NO3− is produced primarily by this process, and is likely limited by the availability of mineral cation-containing aerosol surface area. Modeling of NO3− and HNO3 by thermodynamic equilibrium models (ISORROPIA II and E-AIM) reveals the importance of including mineral cations in the southeastern United States to accurately balance ion species and predict gas–aerosol phase partitioning.

Filter-based PM2.5 samples were chemically analyzed to investigate secondary organic aerosol (SOA) formation from isoprene in a rural atmosphere of the southeastern US influenced by both anthropogenic sulfur dioxide (SO2) and ammonia (NH3) emissions. Daytime PM2.5 samples were collected during summer 2010 using conditional sampling approaches based on pre-defined high and low SO2 or NH3 thresholds. Known molecular-level tracers for isoprene SOA formation, including 2-methylglyceric acid, 3-methyltetrahydrofuran-3,4-diols, 2-methyltetrols, C5-alkene triols, dimers, and organosulfate derivatives, were identified and quantified by gas chromatography coupled to electron ionization mass spectrometry (GC/EI-MS) and ultra performance liquid chromatography coupled to electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-Q-TOFMS). Mass concentrations of six isoprene low-NOx SOA tracers contributed to 12–19% of total organic matter (OM) in PM2.5 samples collected during the sampling period, indicating the importance of the hydroxyl radical (OH)-initiated oxidation (so-called photooxidation) of isoprene under low-NOx conditions that lead to SOA formation through reactive uptake of gaseous isoprene epoxydiols (IEPOX) in this region. The contribution of the IEPOX-derived SOA tracers to total organic matter was enhanced by 1.4% (p = 0.012) under high-SO2 sampling scenarios, although only weak associations between aerosol acidity and mass of IEPOX SOA tracers were observed. This suggests that IEPOX-derived SOA formation might be modulated by other factors simultaneously, rather than only aerosol acidity. No clear associations between isoprene SOA formation and high or low NH3 conditional samples were found. Positive correlations between sulfate aerosol loadings and IEPOX-derived SOA tracers for samples collected under all conditions indicates that sulfate aerosol could be a surrogate for surface accommodation in the uptake of IEPOX onto preexisting aerosols.

Research has shown that lighting can have an influence on wellbeing, health and performance. In this study, we explore whether lighting preferences reflect these effects. Results of a longitudinal field study by Begemann and colleagues (1997) revealed that on average, office employees’ preferred a higher illuminance than prescribed by current standards for office environments, which are mainly based on ergonomic needs for visual tasks. In addition, they found that the light preferences varied with time of day – roughly following a natural daylight curve. These individual light preferences are said to also depend on a person’s level of alertness and mood, although this has not been investigated yet. In this study, we explored whether time of day, daylight contribution, alertness and mood have an influence on light preference. We hypothesized that people would prefer more intense light when they felt less alert.