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Katherine McDermott,1,2 Alexander Mattia Presciutti,1,2 Nadine Levey,1 Julie Brewer,1 Christina L Rush,1,2 Natalia Giraldo-Santiago,1,3 Tony V Pham,1,2 Roger Pasinski,4 Neda Yousif,4 Milton Gholston,4 Vidya Raju,4 Jonathan Greenberg,1,3 Christine S Ritchie,2,3 Ana-Maria Vranceanu1,2 1Center for Health Outcomes and Interdisciplinary Research, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA; 2Harvard Medical School, Boston, MA, USA; 3Center for Aging and Serious Illness, Massachusetts General Hospital, Boston, MA, USA; 4MGH Revere HealthCare Center, Revere, MA, USACorrespondence: Ana-Maria Vranceanu, Center for Health Outcomes and Interdisciplinary Research, Department of Psychiatry, Massachusetts General Hospital/Harvard Medical School, One Bowdoin Square, 1st Floor, Suite 100, Boston, MA, 02114, USA, Email avranceanu@mgh.harvard.eduPurpose: Chronic pain is highly prevalent and disabling for older adults, particularly those from underserved communities. However, there is an absence of research on how contextual (eg, community/societal) factors interact with pain for these patients. Informed by the socio-ecological model, this study aimed to elucidate the individual, interpersonal, community, and societal factors associated with chronic pain from the perceptions of older adult patients and medical staff in a community clinic.Patients and Methods: In this qualitative study, we conducted four focus groups and two interviews with medical staff (n=25) and three focus groups and seven individual interviews with older adult patients with chronic pain (n=18). Participants were recruited using purposive sampling from an ethnically and economically diverse primary care clinic in the greater Boston community. We transcribed assessments and thematically analyzed data using a hybrid deductive-inductive approach.Results: At the individual level, we identified three themes: (1) older adults with complex care needs, (2) impact of pain (including on physical, emotional, work, and identity functioning), and (3) coping with pain. At the interpersonal level, complex relationships with (1) social supports and (2) medical staff emerged as themes. The need for (1) resources and (2) culturally informed care was identified at the community level, and socioeconomic status impacting the availability of resources for managing chronic pain emerged for the societal domain.Conclusion: Findings underscore the intersection of factors contributing to the experience of pain among older adults from underserved communities. Our findings highlight the need to develop and implement treatments that fully address the experience of older adults with chronic pain at the individual, interpersonal, community, and societal levels.Keywords: community clinic, pain, health disparities

Lisa R LaRowe,1,2 Jafar Bakhshaie,3,4 Ana-Maria Vranceanu,3,4 Jonathan Greenberg3,4 1Mongan Institute Center for Aging and Serious Illness, Division of Palliative Care and Geriatric Medicine, Massachusetts General Hospital, Boston, MA, USA; 2Department of Medicine, Harvard Medical School, Boston, MA, USA; 3Center for Health Outcomes and Interdisciplinary Research, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA; 4Department of Psychiatry, Harvard Medical School, Boston, MA, USACorrespondence: Ana-Maria Vranceanu, Center for Health Outcomes and Interdisciplinary Research, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA, Email avranceanu@mgh.harvard.eduPurpose: Improving physical function is key to decreasing the burden of chronic pain across the lifespan. Although mind-body interventions show promise in increasing physical function in chronic pain, very little is known about whether older and younger adults derive similar benefit. Indeed, older adults experience higher rates of chronic pain and greater impacts of pain on physical function compared to younger adults. Therefore, additional work is needed to determine the extent of benefit older versus younger adults receive from a mind-body intervention. Here, we examined age differences in the effects of two mind-body and walking programs on pain and multimodal physical function.Participants and Methods: Participants were 82 individuals with heterogenous chronic musculoskeletal pain (66% female, 57% aged ≥ 50 years) who participated in a feasibility randomized controlled trial of two mind-body interventions. They completed self-reported (WHODAS 2.0), performance-based (6-minute walk test), and objective (accelerometer-measured step count) measures of physical function, as well as self-report measures of pain intensity, before and after the intervention.Results: Results indicated that adults aged ≥ 50 (vs adults aged < 50) demonstrated greater improvements in performance-based physical function (6-minute walk test) and reductions in pain during activity. No age differences in the effects of the intervention on self-reported or objectively measured physical function were observed.Conclusion: Collectively, these findings suggest that older adults can achieve equivalent or greater benefits from mind-body programs for chronic pain, despite facing unique challenges to chronic pain management (eg, multimorbidity, greater sedentary behavior).Keywords: older adults, physical function, pain, disability, mindfulness

Brenda C Lovette,1,2 Sarah M Bannon,2,3 Daphne Catherine Spyropoulos,4 Ana-Maria Vranceanu,2,3 Jonathan Greenberg2,3 1Department of Rehabilitation Sciences, MGH Institute of Health Professions, Boston, MA, USA; 2Center for Health Outcomes and Interdisciplinary Research, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA; 3Department of Psychiatry, Harvard Medical School, Boston, MA, USA; 4Graduate School of Education, Fordham University, New York, NY, USACorrespondence: Jonathan Greenberg, Center for Health Outcomes and Interdisciplinary Research, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA, Email jgreenberg5@mgh.harvard.eduObjective: Chronic orofacial pain is prevalent and debilitating. Psychological and social factors place a heavy burden on this population but are often overlooked. Here, we offer the first comprehensive qualitative conceptualization of the challenges of living with chronic orofacial pain through a biopsychosocial perspective to inform multifaceted care for this population.Design: We employed a qualitative thematic analysis of open text responses using a hybrid inductive-deductive approach and a biopsychosocial framework.Methods: Two hundred and sixty participants with chronic orofacial pain responded to an open-ended question: “What is the biggest challenge you face in managing your condition?” by typing their responses into a text box as part of an online survey. We mapped responses onto biomedical, psychological, and social themes (deductive) and concurrently identified findings within each theme that emerged directly from the data (inductive).Results: Subthemes within the biomedical theme included challenges with biomedical pain management, medication side effects, sensory triggers, physical symptoms of stress/tension, and biological functions and related activities of daily living. Subthemes within the psychological theme included anxiety, depression, emotional symptoms of stress, unpredictability/uncertainty of pain, and psychological and cognitive aspects of medication management. Subthemes within the social theme included social relational, experience with providers, socioeconomics and access to care, and roles and responsibilities.Conclusion: Chronic orofacial pain is associated with multifaceted challenges. Consideration of individuals’ experiences of biomedical, psychological, and social challenges in the assessment, referral, and treatment of chronic orofacial pain holds the potential to promote more comprehensive, patient-centered care for this population.Keywords: chronic orofacial pain, biopsychosocial model, qualitative research, thematic analysis

Jonathan Greenberg,1– 3 Jafar Bakhshaie,1– 3 Brenda C Lovette,3,4 Ana-Maria Vranceanu1– 3 1Integrated Brain Health Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA; 2Harvard Medical School, Boston, MA, USA; 3Center for Health Outcomes and Interdisciplinary Research (CHOIR), Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA; 4MGH Institute of Health Professions, Boston, MA, USACorrespondence: Jonathan Greenberg, Integrated Brain Health Clinical and Research Program & Center for Health Outcomes and Interdisciplinary Research (CHOIR), Department of Psychiatry, Massachusetts General Hospital / Harvard Medical School, One Bowdoin Square, 1st Floor, Suite 106, Boston, MA, 02114, USA, Email jgreenberg5@mgh.harvard.eduBackground: Chronic orofacial pain is associated with substantial pain-related disability and emotional distress. Understanding the relationship between individuals’ coping strategies and pain-related outcomes is important yet understudied in this population.Purpose: To test the cross-sectional association of three coping strategies (pain catastrophizing, kinesiophobia and mindfulness) to four pain-related outcomes (depression, anxiety, pain intensity, and pain-related disability) among individuals with chronic orofacial pain, after accounting for relevant demographic and clinical variables.Methods: Individuals (N=303) with heterogeneous chronic orofacial pain (eg, trigeminal neuralgia, other trigeminal neuropathic pain, persistent idiopathic facial pain and other types) completed self-report measures of coping (Pain Catastrophizing Scale, Tampa Scale of Kinesiophobia, and the 15-item Five Facet Mindfulness Questionnaire), pain intensity and pain-related disability (Graded Chronic Pain Scale), and PROMIS measure of anxiety and depression. We conducted 4 two-step hierarchical regressions for each of the four pain-related and emotional outcomes, with the first step including demographic and clinical covariates, and the second step including the three coping variables together.Results: Pain catastrophizing was the only coping variable significantly associated with pain intensity (B=0.362, SE=0.115, p=0.002, 3% variance explained) and pain-related disability (B =0.813, SE=0.162, p< 0.001, 7% variance explained). Pain catastrophizing (B=0.231-0.267, SE=0.046-0.051-0.050, p< 0.001), kinesiophobia (B=0.201-0.316, SE=0.081-0.084, p< 0.001-0.018), and mindfulness (B=0.231– 0.306, SE=0.046-0.067, p< 0.001) were each independently associated with symptoms of anxiety and depression, with the largest incremental variance added by catastrophizing (5– 8%) and mindfulness (5%).Conclusion: Pain catastrophizing appears to be an important intervention target to improve pain intensity, pain-related disability, anxiety and depression among individuals with chronic orofacial pain. Kinesiophobia and mindfulness may be additional treatment targets for interventions to improve anxiety and depression.Keywords: chronic orofacial pain, coping, pain-related disability, anxiety, depression

The inclusion of students with autism and other special needs into the general education curriculum continues to be a challenging process for school communities in the United States of America (US) and, increasingly, abroad. Although inclusion continues to be a challenging process for those involved, the global demand is growing. Traditionally, this initiative has originated from advocates such as parents and communities who represent the students. With enough pressure from constituents of the system, those efforts may be converted into policy through the local education department. The US has led the inclusion movement and many other developed nations have followed suit in recent decades. Consequently, more and more schools are focused on building inclusive school communities. These programs see the value of a balanced approach that emphasizes curriculum coupled with pedagogy. This paper provides an overview of the history of the inclusion movement in the Hong Kong Special Administrative Region of China. Three main types of school systems in the region are explained, and one successful inclusive school model will be described with outcome data included. Multiple factors that affect the development of the inclusion movement will also be discussed.

Jonathan Greenberg,1,2 Ryan A Mace,1,2 Sarah M Bannon,1,2 Ronald J Kulich,2,3 Ana-Maria Vranceanu2 1Integrated Brain Health Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA; 2Harvard Medical School, Boston, MA, USA; 3Center for Pain Medicine, Massachusetts General Hospital, Boston, MA, USACorrespondence: Ana-Maria VranceanuIntegrated Brain Health Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital/Harvard Medical School, One Bowdoin Square, 1st Floor, Suite 100, Boston, MA, 02114, USATel +1 617 724 4977Email avranceanu@mgh.harvard.eduBackground: Improving physical function among patients with chronic pain is critical for reducing disability and healthcare costs. However, mechanisms underlying improvement in patient-reported, performance-based, and ambulatory physical function in chronic pain remain poorly understood.Purpose: To explore psychosocial mediators of improvement in patient-reported, performance-based, and objective/accelerometer-measured physical function among participants in a mind-body activity program.Methods: Individuals with chronic pain were randomized to one of two identical 10-week mind-body activity interventions aimed at improving physical function with (GetActive-Fitbit; N=41) or without (GetActive; N=41) a Fitbit device. They completed self-reported (WHODAS 2.0), performance-based (6-minute walk test), and objective (accelerometer-measured step-count) measures of physical function, as well as measures of kinesiophobia (Tampa Kinesiophobia Scale), mindfulness (CAMS-R), and pain resilience (Pain Resilience Scale) before and after the intervention. We conducted secondary data analyses to test mediation via mixed-effects modeline.Results: Improvements in patient-reported physical function were fully and uniquely mediated by kinesiophobia (Completely Standardized Indirect Effect (CSIE)=.18; CI=0.08, 0.30; medium-large effect size), mindfulness (CSIE=− .14; CI=− 25, − .05; medium effect size) and pain resilience (CSIE=− .07; CI=− .16, − .005; small-medium effect size). Improvements in performance-based physical function were mediated only by kinesiophobia (CSIE=− .11; CI=− 23, − .008; medium effect size). No measures mediated improvements in objective (accelerometer measured) physical function.Conclusion: Interventions aiming to improve patient-reported physical function in patients with chronic pain may benefit from skills that target kinesiophobia, mindfulness, and pain resilience, while those focused on improving performance-based physical function should target primarily kinesiophobia. More research is needed to understand mechanisms of improvement in objective, accelerometer-measured physical function.Trial Registration: ClinicalTrials.gov NCT03412916.Keywords: chronic pain, disability, mind-body, physical function, mediation, psychosocial variables

Jonathan Greenberg,1,2 Ryan A Mace,1,2 Paula J Popok,1 Ronald J Kulich,2,3 Kushang V Patel,4 John W Burns,5 Tamara J Somers,6 Francis J Keefe,7 Michael E Schatman,8,9 Ana-Maria Vrancenanu1,2 1Integrated Brain Health Clinical and Research Program, Massachusetts General Hospital, Boston, MA, USA; 2Harvard Medical School, Boston, MA, USA; 3Center for Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; 4Department of Anesthesiology & Pain Medicine, University of Washington, Seattle, WA, USA; 5Division of Behavioral Sciences, Rush Medical College, Chicago, IL, USA; 6Psychiatry & Behavioral Sciences, Duke University School of Medicine, Durham, NC, USA; 7Department of Medicine, Duke University School of Medicine, Durham, NC, US; 8Department of Diagnostic Sciences, Tufts University School of Dental Medicine, Boston, MA, USA; 9Department of Public Health and Community Medicine, Tufts University School of Medicine, Boston, MA, USACorrespondence: Ana-Maria Vrancenanu Email avranceanu@mgh.harvard.eduBackground: Improving all aspects of physical function is an important goal of chronic pain management. Few studies follow recent guidelines to comprehensively assess physical function via patient-reported, performance-based, and objective/ambulatory measures.Purpose: To test 1) the interrelation between the 3 types of physical function measurement and 2) the association between psychosocial factors and each type of physical function measurement.Methods: Patients with chronic pain (N=79) completed measures of: 1) physical function (patient-reported disability; performance-based 6-minute walk-test; objective accelerometer step count); 2) pain and non-adaptive coping (pain during rest and activity, pain-catastrophizing, kinesiophobia); 3) adaptive coping (mindfulness, general coping, pain-resilience); and 4) social-emotional dysfunction (anxiety, depression, social isolation and emotional support). First, we tested the interrelation among the 3 aspects of physical function. Second, we used structural equation modeling to test associations between psychosocial factors (pain and non-adaptive coping, adaptive coping, and social-emotional dysfunction) and each measurement of physical function.Results: Performance-based and objective physical function were significantly interrelated (r=0.48, p< 0.001) but did not correlate with patient-reported disability. Pain and non-adaptive coping (β=0.68, p< 0.001), adaptive coping (β=− 0.65, p< 0.001) and social-emotional dysfunction (β=0.65, p< 0.001) were associated with patient-reported disability but not to performance-based or objective physical function (ps> 0.1).Conclusion: Results suggest that patient-reported physical function may provide limited information about patients’ physical capacity or ambulatory activity. While pain and non-adaptive reactions to it, adaptive coping, and social-emotional dysfunction may potentially improve patient-reported physical function, additional targets may be needed to improve functional capacity and ambulatory activity.Trial Registration: ClinicalTrials.gov NCT03412916.Keywords: physical function, chronic pain, six-minute walk test, accelerometer, psychosocial factors

Despite the known biochemical production of a range of aromatic compounds by plants and the presence of benzenoids in floral scents, the emissions of only a few benzenoid compounds have been reported from the biosphere to the atmosphere. Here, using evidence from measurements at aircraft, ecosystem, tree, branch and leaf scales, with complementary isotopic labeling experiments, we show that vegetation (leaves, flowers, and phytoplankton) emits a wide variety of benzenoid compounds to the atmosphere at substantial rates. Controlled environment experiments show that plants are able to alter their metabolism to produce and release many benzenoids under stress conditions. The functions of these compounds remain unclear but may be related to chemical communication and protection against stress. We estimate the total global secondary organic aerosol potential from biogenic benzenoids to be similar to that from anthropogenic benzenoids (~10 Tg y(-1)), pointing to the importance of these natural emissions in atmospheric physics and chemistry.

In this report, we describe the gross, histopathology, and immunohistochemical findings of a thyroblastoma that arose in the right lobe of the thyroid gland in a 2‐month‐old rhesus macaque (Macaca mulatta). [ABSTRACT FROM AUTHOR]

Jonathan Greenberg,1,2 Ann Lin,1 Emily L Zale,1 Ronald J Kulich,2,3 Peter James,2,4 Rachel A Millstein,1,2 Hannah Shapiro,5 Michael E Schatman,6,7 Robert R Edwards,2,8 Ana-Maria Vranceanu1,2 1Integrated Brain Health Clinical and Research Program, Massachusetts General Hospital, Boston, MA, USA; 2Harvard Medical School, Boston, MA, USA; 3Center For Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; 4Department of Population Medicine, Harvard T. H. Chan School of Public Health, Boston, MA, USA; 5Department of Biology, Tufts University, Medford, MA, USA; 6Research and Network Development, Boston Pain Care, Waltham, MA, USA; 7Department of Public Health and Community Medicine, Tufts University School of Medicine, Boston, MA, USA; 8Pain Management Center, Brigham and Women’s Hospital, Boston, MA, USACorrespondence: Ana-Maria VranceanuIntegrated Brain Health Clinical and Research Program, Department of Psychiatry, Massachusetts General Hospital/Harvard Medical School, One Bowdoin Square, 1 st Floor, Suite 100, Boston, MA, USATel +1 6177244977Fax +1 617-643-8777Email avranceanu@mgh.harvard.eduBackground: Increasing physical function is a challenging, yet imperative goal of pain management programs. Physical activity can improve physical function, but uptake is low due to chronic pain misconceptions, poor pain management skills, and doing too much too soon.Purpose: To increase physical function by 1) adapting an evidence-based, group, mind-body program to address the needs of patients with heterogeneous chronic pain and to facilitate individually tailored quota-based pacing with a Fitbit (GetActive with Fitbit) or without it (GetActive) (phase 1), and 2) assessing preliminary feasibility benchmarks (phase 2).Methods: We followed evidence based frameworks for developing interventions and for early feasibility testing. In phase 1 we conducted 4 focus groups with 22 patients with heterogeneous chronic pain and adapted the mind-body program. In phase 2 we conducted a nonrandomized pilot trial of the 2 programs (N=7 and 6) with qualitative exit interviews.Results: Focus groups showed high interest in increasing activity, a preference for walking linked to pleasurable activities, using a Fitbit to track number of steps, and learning skills to manage pain and aid with increased activity. Both programs had good to excellent feasibility markers. Participation in both programs was associated with signal of improvements in physical and emotional function, as well as intervention targets. Exit interviews confirmed high satisfaction and suggested modification.Conclusion: Results informed subsequent adaptations of the 2 programs and methodology for an ongoing pilot randomized controlled trial (RCT) of the 2 programs, necessary before an efficacy RCT of the 2 programs against an education control.Keywords: mind-body, chronic pain, fitbit, physical activity, focus groups, feasibility, physical function

Total OH reactivity was measured during the Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen-Southern Rocky Mountain 2008 field campaign (BEACHON-SRM08) held at Manitou Experimental Forest (MEF) in Colorado USA in August, 2008. The averaged total OH reactivity was 6.7s-1, smaller than that measured in urban (33.4s-1, Yoshino etal., 2012) and suburban (27.7s-1, Yoshino etal., 2006) areas in Tokyo in the same season, while sporadically high OH reactivity was also observed during some evenings. The total OH reactivity measurements were accompanied by observations of traces species such as CO, NO, NOy, O3 and SO2 and Volatile Organic Compounds (VOCs). From the calculation of OH reactivity based on the analysis of these trace species, 46.3% of OH reactivity for VOCs came from biogenic species that are dominated by 2-methyl-3-buten-2-ol (MBO), and monoterpenes. MBO was the most prominent contribution to OH reactivity of all trace species. A comparison of observed and calculated OH reactivity shows that the calculated OH reactivity is 29.5% less than the observed value, implying the existence of missing OH sinks. One of the candidates of missing OH is thought to be the oxidation products of biogenic species. © 2013 Elsevier Ltd.

The MIRAGE-Shanghai experiment was designed to characterize the factors controlling regional air pollution near a Chinese megacity (Shanghai) and was conducted during September 2009. This paper provides information on the measurements conducted for this study. In order to have some deep analysis of the measurements, a regional chemical/ dynamical model (version 3 of Weather Research and Forecasting Chemical model - WRF-Chemv3) is applied for this study. The model results are intensively compared with the measurements to evaluate the model capability for calculating air pollutants in the Shanghai region, especially the chemical species related to ozone formation. The results show that the model is able to calculate the general distributions (the level and the variability) of air pollutants in the Shanghai region, and the differences between the model calculation and the measurement are mostly smaller than 30 %, except the calculations of HONO (nitrous acid) at PD (Pudong) and CO (carbon monoxide) at DT (Dongtan). The main scientific focus is the study of ozone chemical formation not only in the urban area, but also on a regional scale of the surrounding area of Shanghai. The results show that during the experiment period, the ozone photochemical formation was strongly under the VOC (volatile organic compound)-limited condition in the urban area of Shanghai. Moreover, the VOC-limited condition occurred not only in the city, but also in the larger regional area. There was a continuous enhancement of ozone concentrations in the downwind of the megacity of Shanghai, resulting in a significant enhancement of ozone concentrations in a very large regional area in the surrounding region of Shanghai. The sensitivity study of the model suggests that there is a threshold value for switching from VOC-limited condition to NOx (nitric oxide and nitrogen dioxide)-limited condition. The threshold value is strongly dependent on the emission ratio of NOx /VOCs. When the ratio is about 0.4, the Shanghai region is under a strong VOC-limited condition over the regional scale. In contrast, when the ratio is reduced to about 0.1, the Shanghai region is under a strong NOx-limited condition. The estimated threshold value (on the regional scale) for switching from VOC-limited to NOx-limited condition ranges from 0.1 to 0.2. This result has important implications for ozone production in this region and will facilitate the development of effective O3 control strategies in the Shanghai region. © Author(s) 2013. CC Attribution 3.0 License.

We present a detailed analysis of OH observations from the BEACHON (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen)-ROCS (Rocky Mountain Organic Carbon Study) 2010 field campaign at the Manitou Forest Observatory (MFO), which is a 2-methyl-3-butene-2-ol (MBO) and monoterpene (MT) dominated forest environment. A comprehensive suite of measurements was used to constrain primary production of OH via ozone photolysis, OH recycling from HO2, and OH chemical loss rates, in order to estimate the steady-state concentration of OH. In addition, the University of Washington Chemical Model (UWCM) was used to evaluate the performance of a near-explicit chemical mechanism. The diurnal cycle in OH from the steady-state calculations is in good agreement with measurement. A comparison between the photolytic production rates and the recycling rates from the HO2 + NO reaction shows that recycling rates are ~20 times faster than the photolytic OH production rates from ozone. Thus, we find that direct measurement of the recycling rates and the OH loss rates can provide accurate predictions of OH concentrations. More importantly, we also conclude that a conventional OH recycling pathway (HO2 + NO) can explain the observed OH levels in this non-isoprene environment. This is in contrast to observations in isoprene-dominated regions, where investigators have observed significant underestimation of OH and have speculated that unknown sources of OH are responsible. The highly-constrained UWCM calculation under-predicts observed HO2 by as much as a factor of 8. As HO2 maintains oxidation capacity by recycling to OH, UWCM underestimates observed OH by as much as a factor of 4. When the UWCM calculation is constrained by measured HO2, model calculated OH is in better agreement with the observed OH levels. Conversely, constraining the model to observed OH only slightly reduces the model-measurement HO2 discrepancy, implying unknown HO2 sources. These findings demonstrate the importance of constraining the inputs to, and recycling within, the ROx radical pool (OH + HO2 + RO2).

We have conducted a comprehensive observational study to determine the mixing ratios of atmospheric chemical species and total OH reactivity in central Tokyo, in order to diagnose the air quality during summer and winter 2007 and autumn 2009. Concentrations of over 70 reactive trace species were continuously measured throughout each season. The total OH reactivity was measured directly using a laser-induced pump and probe technique. The observed chemical species exhibited seasonal variations. There was a good correlation between NO and CO in winter, but not in summer. This indicates that during winter, vehicle exhaust provided a significant source of NO in central Tokyo, while photolysis of NO 2 was dominant in summer. Similar values (approximately 30s -1) for the averaged total OH reactivity were observed in both summer and autumn during the daytime. However, VOCs accounted for a larger percentage of the OH reactivity in summer, while NO x was more dominant in autumn. We find that photochemical processes leading to oxidant production via VOCs dominated OH removal in summer, while the production of nitric acid from the reaction between OH and NO 2 was dominant in autumn, by-passing the oxidant production pathways and resulting in reduced oxidant formation. © 2011 Elsevier Ltd.

We present OH reactivity measurements using the comparative reactivity method with a branch enclosure technique for four different tree species (red oak, white pine, beech and red maple) in the UMBS PROPHET tower footprint during the Community Atmosphere Biosphere INteraction EXperiment (CABINEX) field campaign in July of 2009. Proton Transfer Reaction-Mass Spectrometry (PTR-MS) was sequentially used as a detector for OH reactivity and BVOC concentrations including isoprene and monoterpenes (MT) for enclosure air. Therefore, the measurement dataset contains both measured and calculated OH reactivity from well-known BVOC. The results indicate that isoprene and MT, and in one case a sesquiterpene, can account for the measured OH reactivity. Significant discrepancy between measured OH reactivity and calculated OH reactivity from isoprene and MT is found for the red maple enclosure dataset but it can be reconciled by adding reactivity from emission of a sesquiterpene, α-farnesene, detected by GC-MS. This leads us to conclude that no significant unknown BVOC emission contributed to ambient OH reactivity from these trees at least during the study period. However, this conclusion should be followed up by more comprehensive side-by-side intercomparison between measured and calculated OH reactivity and laboratory experiments with controlled temperature and light environments to verify effects of those essential parameters towards unknown/unmeasured reactive BVOC emissions. This conclusion leads us to explore the contribution towards ambient OH reactivity (the dominant OH sink in this ecosystem) oxidation products such as hydroxyacetone, glyoxal, methylglyoxal and C4 and C5-hydroxycarbonyl using recently published isoprene oxidation mechanisms (Mainz Isoprene Mechanism II and Leuven Isoprene Mechanism). Evaluation of conventionally unmeasured first generation oxidation products of isoprene and their possible contribution to ambient missing OH reactivity indicates that the ratio of OH reactivity from unmeasured products over OH reactivity from MVK + MACR is strongly dependent on NO concentrations. The unmeasured oxidation products can contribute ~7.2 % (8.8 % from LIM and 5.6 % by MIM 2 when NO = 100 pptv) of the isoprene contribution towards total ambient OH reactivity. This amount can explain ~8.0 % (9.7 % from LIM and 6.2 % from MIM 2) of missing OH reactivity, reported by Di Carlo et al. (2004) at the same site. Further study on the contribution from further generation of unmeasured oxidation products is needed to constrain tropospheric photochemical reactivity of BVOC that have important implications for both photochemical ozone and secondary organic aerosol formation.

Aerosol physical and chemical properties were measured in a forest site in central Amazonia (Cuieiras reservation, 2.61S; 60.21W) during the dry season of 2004 (Aug-Oct). Aerosol light scattering and absorption, mass concentration, elemental composition and size distributions were measured at three tower levels (Ground: 2 m; Canopy: 28 m, and Top: 40 m). For the first time, simultaneous eddy covariance fluxes of fine mode particles and volatile organic compounds (VOC) were measured above the Amazonian forest canopy. Aerosol fluxes were measured by eddy covariance using a Condensation Particle Counter (CPC) and a sonic anemometer. VOC fluxes were measured by disjunct eddy covariance using a Proton Transfer Reaction Mass Spectrometer (PTR-MS). At nighttime, a strong vertical gradient of phosphorus and potassium in the aerosol coarse mode was observed, with higher concentrations at Ground level. This suggests a source of primary biogenic particles below the canopy. Equivalent black carbon measurements indicate the presence of light-absorbing aerosols from biogenic origin. Aerosol number size distributions typically consisted of superimposed Aitken (76 nm) and accumulation modes (144 nm), without clear events of new particle formation. Isoprene and monoterpene fluxes reached respectively 7.4 and 0.82 mg m-2 s-1 around noon. An average fine particle flux of 0.05 ± 0.10 106 m-2 s-1 was calculated, denoting an equilibrium between emission and deposition fluxes of fine mode particles at daytime. No significant correlations were found between VOC and fine mode aerosol concentrations or fluxes. © 2009 Elsevier Ltd.