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This study uses mobile monitoring to gain a better understanding of particulate matter (PM) sources in two areas of Central and Outer London, UK. We find that, unlike emissions of nitrogen oxides (NO + NO2 = NOx), which are elevated in Central London due to the high number of diesel vehicles and congestion, fine particulate matter (PM2.5) emissions are well-controlled. This finding provides evidence for the effectiveness of vehicle particulate filters, supporting the view that their widespread adoption has mitigated PM2.5 emissions, even in the highly dieselized area of Central London. However, mobile monitoring also reveals infrequent elevated PM2.5 concentrations caused by malfunctioning vehicles. These events were confirmed through simultaneous measurements of PM2.5 and sulfur dioxide (SO2), the latter being a strong tracer of engine lubricant combustion. A single event from a gasoline car, representing just 0.15% of the driving distance in Outer London, was responsible for 7.4% of the ΔPM2.5 concentration above background levels, highlighting the ongoing importance of addressing high-emission vehicles. In a novel application of mobile monitoring, we demonstrate the ability to identify and quantify non-vehicular sources of PM. Among the sources unambiguously identified are construction activities, which result in elevated concentrations of coarse particulate matter (PMcoarse = PM10 − PM2.5). The mobile measurements clearly highlight the spatial extent of the influence of such sources, which would otherwise be difficult to determine. Furthermore, these sources are shown to be weather-dependent, with PMcoarse concentrations reduced by 62.1% during wet conditions compared to dry ones. [ABSTRACT FROM AUTHOR]

Racial/ethnic minoritized youth are underrepresented in autism research. Documented inequities in accessibility to and utilization of autism-specific services highlight the importance of better understanding for whom and under what conditions autism evidence-based practices (EBPs) work. This report examines the race, ethnicity, sex, and gender of school-based autism research participants (e.g. educators, students), given schools are the most common setting in which autistic youth receive services in the United States (US). Data across 14 years of research, for eight school-based studies in the US, showed that while most teachers identified as non-Hispanic White, over half of the youth sampled identified as being of a racial/ethnic minoritized background. Findings provide insights into who is being served in school-based autism research and how school partnerships may increase diversity among autism research participants and offer a means of reducing existing barriers. Researchers should continue to utilize schools to reach diverse populations and consider how demographic characteristics of school staff affect EBP effectiveness. Researchers should continue to better understand the impact of the EBP, provider, and setting on outcomes. Schools are the main provider of behavioral health services in the United States (US). Conducting research in schools may help increase access for autistic youth, but there is limited research about who participates in school-based autism research. The researchers examined data spanning 14 years of participation in school-based autism research. All data were collected in the US. Researchers found that in this sample, more than half of the youth identified as racial/ethnic minoritized (REM) youth. However, demographics of sampled youth were significantly different than expected, based on publicly available school-based population demographics. More youth identified as White non-Hispanic than would be expected in those schools. Majority of the sampled educators also identified as White non-Hispanic. High percentages of autistic REM youth suggest school-based autism research may be an effective way of providing services to more diverse populations. However, sampled schools were also not representative of a US national sample, with sampled schools having fewer White non-Hispanic youth than would be expected from US national statistics. Complexity around representation of schools sampled and demographics of service environments suggests a need for more research. [ABSTRACT FROM AUTHOR]

In recent years, clean air policies have led to reductions in air pollution across China. Alongside this, emerging carbon neutrality (CN) policies that aim to address the impacts of climate change may also deliver air quality (AQ) co-benefits or climate penalties. Different CN policies will lead to different changes in volatile organic compound (VOC), NO x and particulate matter (PM) emissions, which will in turn impact the photochemical production of secondary pollutants such as ozone (O 3). It is currently unclear how different combinations of AQ and CN policies may impact in situ O 3 production across China in the future. A detailed chemical box model incorporating the Master Chemical Mechanism was developed to investigate the impact of combined AQ and CN policies on O 3 formation in Beijing. The Multi-resolution Emission Inventory model for Climate and air pollution research (MEIC) and the Dynamic Projection model for Emissions in China (DPEC) were used to estimate future pollutant mixing ratios, relative to ambient observations of 35 VOCs, NO x , CO and aerosol surface area (ASA) during the APHH-Beijing 2017 summer campaign. The most ambitious policy scenario, "Ambitious Pollution 1.5D Goals", led to the largest reduction in O 3 production by 2060 but was not the most impactful scenario for reducing O 3 production between 2030–2045. Larger reductions were observed under the "Ambitious Pollution Neutral Goals" policy, which focuses on achieving net zero by 2060. O 3 production was found to be most sensitive to changes in the OLE2 group of VOCs (alkenes where kOH>7×104 ppm -1 min -1 ; a 5 % increase in OLE2 increased simulated O 3 production by 1.12 %). However, reducing less reactive but higher concentration species in Beijing (such as short-chain alkanes) led to larger reductions in O 3 production under all scenarios. O 3 production was not sensitive to changes in ASA, with a 69 % decrease in ASA leading to a change of <1 % in O 3. However, doubling biogenic VOCs in the model further increased O 3 production in 2060 under all future scenarios by up to 18 %, indicating that the influence of future climate-induced changes in biogenic emissions may have a significant impact on in situ O 3 formation in Beijing. This study highlights that the emission trajectories of certain specific VOCs are highly influential in determining possible future O 3 air quality effects that may arise from increasing ambient temperatures and decarbonisation in Beijing. [ABSTRACT FROM AUTHOR]

Parents of autistic children have historically reported hardships related to raising their children. However, the access to resources related to the childrearing of an autistic child is not equitable, therefore resulting in exacerbated difficulties for parents in low-resource settings. In these situations, peer support may be a protective factor for parental resilience in which they receive various supports from other parents of an autistic child with similar experiences. Despite its potential utility, little is known about such parent-to-parent support as evidenced by no synthesis of relevant literature. To address this gap, we present a scoping review of 25 studies that included parent-to-parent support among parents of autistic children. Across these studies, a total of 141 and 747 parents participated as parent mentors and mentees with some heterogeneity in their demographic characteristics. We also identified how parent mentors were trained to provide support to their peers and social validity data related to parent-to-parent support and provided implications for future intervention research. Parents of autistic children have long reported feelings of isolation and increased stress during and after receiving their child's diagnosis. Increasing global prevalence of autism also calls for increased services and supports to meet the needs of these families, but most parents who live in low-resource settings still report exacerbated barriers. This may indicate the need for diversifying intervention delivery models to increase contextual fit and enhance implementation effects for different populations. For example, many parents have reported parent-to-parent (P2P) model to be a source of emotional support, advocacy, and knowledge related to their child's diagnosis, and practical advice. However, little is known about this topic due to the lack of synthesis of relevant autism literature. To address this gap, we conducted a literature review to gain a deeper understanding of how P2P support is used. We identified 25 studies based on our inclusion and exclusion criteria, which we coded to extract variables such as demographic information of participants, types of P2P, dosage, target outcomes, and social validity. About half of studies focused on providing support groups for parents, and the other half focused on individual matching and mentoring for skill acquisition of parents. Across the included 25 studies, a total of 141 parents participated as parent mentors and 747 parents as parent mentees. We also present implications for future research. [ABSTRACT FROM AUTHOR]

This work investigates temperature's effect on the critical energy release rate using damage mechanics material models and the element deletion method. The energy release rate describes the decrease in total potential energy per increase in crack surface area. The critical energy release rate is widely used as the failure criterion for various elastic and plastic materials. In real-life scenarios, fractures may occur at different temperatures. The temperature dependency of the critical energy release rate for aluminum 2024-T351 and titanium Ti-6Al-4V is studied in this work. We utilized test-data-based advanced material models of these two alloys, considering the strain rate, temperature, and state of stress for plasticity and failure. These material models are used to simulate a three-dimensional fracture specimen to find the critical energy release rate at different temperatures. A new method to calculate the critical energy release rate with the element deletion method is introduced and verified with the virtual crack opening method. This method enables the calculation of the energy release rate in a classical damage mechanics simulation for dynamic cack propagation. The simulation result indicates that the critical energy release rate increases with rising temperatures for these alloys. [ABSTRACT FROM AUTHOR]

There is minimal research on the quality of community partnerships in studies of interventions for autistic children. However, building high quality community engagement in autism intervention research may improve implementation outcomes. This systematic review examined studies that report community partnership in autism intervention research. A total of 135 articles were identified and 11 of these articles were included in the final review. Community partnership data were extracted using indicators from the conceptual framework for assessing research‐practice partnerships (RPP; Henrick et al., Henrick et al., Assessing research‐practice partnerships: Five dimensions of effectiveness, William T. Grant Foundation, 2017) and implementation outcomes data were extracted using the taxonomy of distinct implementation outcomes (Proctor et al., Administration and Policy in Mental Health and Mental Health Services Research, 38:65–76, 2011). Quality of studies were appraised using JBIs critical appraisal tools (Munn et al., JBI Evidence Synthesis, 18:2127–2133, 2020). RPP indicators and implementation outcomes were variably reported across studies. RPP indicators and implementation outcomes more likely to be reported were related to building trust, cultivating partnership relationships, conducting rigorous research to inform action, acceptability, and feasibility. RPP indicators and implementation outcomes less likely to be reported were related to building capacity to engage in partnership work, sustainability, cost, and penetration. Together, these results may suggest the need for increased sustainability and capacity building efforts in partnerships and increased guidelines for reporting outcomes. Lay Summary: This paper reviewed autism intervention studies that report partnerships between researchers and community members. The quality of the partnerships and outcomes of implementing the interventions were found to be variably reported. There may be a need for clearer guidelines on reporting outcomes of partnerships between researchers and community members and partnerships may benefit from increased focus on building capacity and sustainability. [ABSTRACT FROM AUTHOR]

In recent years, clean air policies have led to reductions in air pollution across China. Alongside this, emerging carbon neutrality (CN) policies that aim to address the impacts of climate change may also deliver air quality (AQ) co-benefits or climate penalties. Different CN policies will lead to different changes in volatile organic compound (VOC), NOx, and particulate matter (PM) emissions, which will in-turn impact the photochemical production of secondary pollutants such as ozone (O3). It is currently unclear how different combinations of AQ and CN policies may impact in situ O3 production across China in the future. A detailed chemical box model incorporating the Master Chemical Mechanism was developed to investigate the impact of combined AQ and CN policies on O3 formation in Beijing. The Multi-resolution Emission Inventory model for Climate and air pollution research (MEIC) and the Dynamic Projection model for Emissions in China (DPEC) were used to estimate future pollutant mixing ratios, relative to ambient observations of 35 VOCs, NOx, CO and aerosol surface area (ASA) during the APHH-Beijing 2017 summer campaign. The most ambitious policy scenario, " Ambitious Pollution 1.5D goals ', led to the largest reduction in O3 production by 2060, but was not the most impactful scenario for reducing O3 production between 2030–2045. Larger reductions were observed under the " Ambitious Pollution Neutral goals " policy which focuses on achieving net zero by 2060. O3 production was found to be most sensitive to changes in the OLE2 group of VOCs (alkenes where k OH > 7 x 104 ppm-1 min-1; a 5 % increase in OLE2 increased simulated O3 production by 1.12 %). However, reducing less reactive but higher concentration species in Beijing (including methanol and short-chain alkanes) led to larger reductions in O3 production under all scenarios. O3 production was not sensitive to changes in ASA, with a 69 % decrease in ASA leading to a change of < 1 % in O3. However, doubling biogenic VOCs in the model further increased O3 production in 2060 under all future scenarios by up to 18 %, indicating that the influence of future climate-induced changes in biogenic emissions may have a significant impact on in situ O3 formation in Beijing. This study highlights that the emission trajectories of certain specific VOCs are highly influential in determining possible future O3 air quality effects that may arise from increasing ambient temperatures and decarbonisation in Beijing. [ABSTRACT FROM AUTHOR]

In recent years, clean air policies have led to reductions in air pollution across China. Alongside this, emerging carbon neutrality (CN) policies that aim to address the impacts of climate change may also deliver air quality (AQ) co-benefits or climate penalties. Different CN policies will lead to different changes in volatile organic compound (VOC), NOx, and particulate matter (PM) emissions, which will in-turn impact the photochemical production of secondary pollutants such as ozone (O3). It is currently unclear how different combinations of AQ and CN policies may impact in situ O3 production across China in the future. A detailed chemical box model incorporating the Master Chemical Mechanism was developed to investigate the impact of combined AQ and CN policies on O3 formation in Beijing. The Multi-resolution Emission Inventory model for Climate and air pollution research (MEIC) and the Dynamic Projection model for Emissions in China (DPEC) were used to estimate future pollutant mixing ratios, relative to ambient observations of 35 VOCs, NOx, CO and aerosol surface area (ASA) during the APHH-Beijing 2017 summer campaign. The most ambitious policy scenario, "Ambitious Pollution 1.5D goals", led to the largest reduction in O3 production by 2060, but was not the most impactful scenario for reducing O3 production between 2030-2045. Larger reductions were observed under the "Ambitious Pollution Neutral goals" policy which focuses on achieving net zero by 2060. O3 production was found to be most sensitive to changes in the OLE2 group of VOCs (alkenes where kOH > 7 x 104 ppm-1 min-1; a 5% increase in OLE2 increased simulated O3 production by 1.12%). However, reducing less reactive but higher concentration species in Beijing (including methanol and short-chain alkanes) led to larger reductions in O3 production under all scenarios. O3 production was not sensitive to changes in ASA, with a 69% decrease in ASA leading to a change of < 1% in O3. However, doubling biogenic VOCs in the model further increased O3 production in 2060 under all future scenarios by up to 18%, indicating that the influence of future climate-induced changes in biogenic emissions may have a significant impact on in situ O3 formation in Beijing. This study highlights that the emission trajectories of certain specific VOCs are highly influential in determining possible future O3 air quality effects that may arise from increasing ambient temperatures and decarbonisation in Beijing. [ABSTRACT FROM AUTHOR]

Although global prevalence of autism has grown substantially, researchers still report inequity in access to evidence-based interventions in many low-resource settings where majority of world's children live. Capacity building of diverse stakeholders in low-resource settings has been suggested to be a potential way to mitigate low levels of access to resources; however, little is known about what these stakeholders consider as helpful strategies in capacity building. In this qualitative research, we conducted five focus groups with 30 Mongolian caregivers of children with autism and 15 individual interviews with professionals in Mongolia. Three themes emerged from this study, including (a) partnership, (b) advocacy, and (c) empowerment. Each theme also contained several categories. For example, partnerships included enhancing collaboration among stakeholders and collaboration with international development agencies; advocacy included parental and legislative advocacy; and empowerment included training for diverse stakeholders, including caregivers and professionals. Implications and directions for future research are also suggested. Prevalence of autism is increasing all around the globe, but there is still great inequity in accessing evidence-based interventions. Although the field of autism research has made great strides in identifying and establishing evidence-based interventions, dissemination and implementation of these interventions have been reported as inequitable. This inequity is especially highlighted in many low-resource settings, such as Mongolia. As a field, there is still much to be learned about what strategies are used by stakeholders in low-resource settings to build capacity and to mitigate the hardships. To gain a deeper understanding of strategies for capacity building within a low-resource setting, we conducted five focus groups with 30 Mongolian caregivers of children with autism and 15 individual interviews with various professionals who work in Mongolia. These stakeholders reported three main strategies, including (a) partnership, (b) advocacy, and (c) empowerment, which included several strategies and implications on capacity-building practices. Furthermore, the findings from this study may suggest important implications for future intervention research. [ABSTRACT FROM AUTHOR]

OH, HO 2 , total and partially speciated RO 2 , and OH reactivity (kOH′) were measured during the July 2015 ICOZA (Integrated Chemistry of OZone in the Atmosphere) project that took place at a coastal site in north Norfolk, UK. Maximum measured daily OH, HO 2 and total RO 2 radical concentrations were in the range 2.6–17 × 10 6 , 0.75–4.2 × 10 8 and 2.3–8.0 × 10 8 molec. cm -3 , respectively. kOH′ ranged from 1.7 to 17.6 s -1 , with a median value of 4.7 s -1. ICOZA data were split by wind direction to assess differences in the radical chemistry between air that had passed over the North Sea (NW–SE sectors) and that over major urban conurbations such as London (SW sector). A box model using the Master Chemical Mechanism (MCMv3.3.1) was in reasonable agreement with the OH measurements, but it overpredicted HO 2 observations in NW–SE air in the afternoon by a factor of ∼ 2–3, although slightly better agreement was found for HO 2 in SW air (factor of ∼ 1.4–2.0 underprediction). The box model severely underpredicted total RO 2 observations in both NW–SE and SW air by factors of ∼ 8–9 on average. Measured radical and kOH′ levels and measurement–model ratios displayed strong dependences on NO mixing ratios, with the results suggesting that peroxy radical chemistry is not well understood under high-NO x conditions. The simultaneous measurement of OH, HO 2 , total RO 2 and kOH′ was used to derive experimental (i.e. observationally determined) budgets for all radical species as well as total RO x (i.e. OH + HO 2 + RO 2). In NW–SE air, the RO x budget could be closed during the daytime within experimental uncertainty, but the rate of OH destruction exceeded the rate of OH production, and the rate of HO 2 production greatly exceeded the rate of HO 2 destruction, while the opposite was true for RO 2. In SW air, the RO x budget analysis indicated missing daytime RO x sources, but the OH budget was balanced, and the same imbalances were found with the HO 2 and RO 2 budgets as in NW–SE air. For HO 2 and RO 2 , the budget imbalances were most severe at high-NO mixing ratios, and the best agreement between HO 2 and RO 2 rates of production and destruction rates was found when the RO 2 + NO rate coefficient was reduced by a factor of 5. A photostationary-steady-state (PSS) calculation underpredicted daytime OH in NW–SE air by ∼ 35 %, whereas agreement (∼ 15 %) was found within instrumental uncertainty (∼ 26 % at 2 σ) in SW air. The rate of in situ ozone production (P (O x)) was calculated from observations of RO x , NO and NO 2 and compared to that calculated from MCM-modelled radical concentrations. The MCM-calculated P (O x) significantly underpredicted the measurement-calculated P (O x) in the morning, and the degree of underprediction was found to scale with NO. [ABSTRACT FROM AUTHOR]

The impact of heterogeneous uptake of HO 2 on aerosol surfaces on radical concentrations and the O 3 production regime in Beijing in summertime was investigated. The uptake coefficient of HO 2 onto aerosol surfaces, γHO2 , was calculated for the AIRPRO campaign in Beijing, in summer 2017, as a function of measured aerosol soluble copper concentration, [Cu 2+ ] eff , aerosol liquid water content, [ALWC], and particulate matter concentration, [PM]. An average γHO2 across the entire campaign of 0.070±0.035 was calculated, with values ranging from 0.002 to 0.15, and found to be significantly lower than the value of γHO2=0.2 , commonly used in modelling studies. Using the calculated γHO2 values for the summer AIRPRO campaign, OH, HO 2 and RO 2 radical concentrations were modelled using a box model incorporating the Master Chemical Mechanism (v3.3.1), with and without the addition of γHO2 , and compared to the measured radical concentrations. The rate of destruction analysis showed the dominant HO 2 loss pathway to be HO 2 + NO for all NO concentrations across the summer Beijing campaign, with HO 2 uptake contributing <0.3 % to the total loss of HO 2 on average. This result for Beijing summertime would suggest that under most conditions encountered, HO 2 uptake onto aerosol surfaces is not important to consider when investigating increasing O 3 production with decreasing [PM] across the North China Plain. At low [NO], however, i.e. <0.1 ppb, which was often encountered in the afternoons, up to 29 % of modelled HO 2 loss was due to HO 2 uptake on aerosols when calculated γHO2 was included, even with the much lower γHO2 values compared to γHO2= 0.2, a result which agrees with the aerosol-inhibited O 3 regime recently proposed by Ivatt et al. (2022). As such it can be concluded that in cleaner environments, away from polluted urban centres where HO 2 loss chemistry is not dominated by NO but where aerosol surface area is high still, changes in PM concentration and hence aerosol surface area could still have a significant effect on both overall HO 2 concentration and the O 3 production regime. Using modelled radical concentrations, the absolute O 3 sensitivity to NO x and volatile organic compounds (VOCs) showed that, on average across the summer AIRPRO campaign, the O 3 production regime remained VOC-limited, with the exception of a few days in the afternoon when the NO mixing ratio dropped low enough for the O 3 regime to shift towards being NO x -limited. The O 3 sensitivity to VOCs, the dominant regime during the summer AIRPRO campaign, was observed to decrease and shift towards a NO x -sensitive regime both when NO mixing ratio decreased and with the addition of aerosol uptake. This suggests that if [NO x ] continues to decrease in the future, ozone reduction policies focussing solely on NO x reductions may not be as efficient as expected if [PM] and, hence, HO 2 uptake to aerosol surfaces continue to decrease. The addition of aerosol uptake into the model, for both the γHO2 calculated from measured data and when using a fixed value of γHO2=0.2 , did not have a significant effect on the overall O 3 production regime across the campaign. While not important for this campaign, aerosol uptake could be important for areas of lower NO concentration that are already in a NO x -sensitive regime. [ABSTRACT FROM AUTHOR]

Challenging behaviors interfere with children's learning, prosocial interactions, and family dynamics. Parents may benefit from receiving training in behavioral principles to prevent and reduce challenging behaviors, especially in low‐resourced communities where services are scarce and scattered. This study implemented an adapted online training on behavioral principles with 15 parents of children with developmental disabilities in Paraguay. Analysis of the pretest and posttest assessment data indicated that parents' knowledge of behavioral principles overall increased, and some changes were found in the reported usage of positive parenting practices. Moreover, qualitative interviews with participants revealed that the intervention delivery in Paraguay was considered acceptable. Therefore, providing access to online training in low‐resourced communities may be a feasible and accessible intervention for parents of children with developmental disabilities. [ABSTRACT FROM AUTHOR]

Fluxes of nitrogen oxides (NOx=NO+NO2) and carbon dioxide (CO2) were measured using eddy covariance at the British Telecommunications (BT) Tower in central London during the coronavirus pandemic. Comparing fluxes to those measured in 2017 prior to the pandemic restrictions and the introduction of the Ultra-Low Emissions Zone (ULEZ) highlighted a 73 % reduction in NOx emissions between the two periods but only a 20 % reduction in CO2 emissions and a 32 % reduction in traffic load. Use of a footprint model and the London Atmospheric Emissions Inventory (LAEI) identified transport and heat and power generation to be the two dominant sources of NOx and CO2 but with significantly different relative contributions for each species. Application of external constraints on NOx and CO2 emissions allowed the reductions in the different sources to be untangled, identifying that transport NOx emissions had reduced by >73 % since 2017. This was attributed in part to the success of air quality policy in central London but crucially due to the substantial reduction in congestion that resulted from pandemic-reduced mobility. Spatial mapping of the fluxes suggests that central London was dominated by point source heat and power generation emissions during the period of reduced mobility. This will have important implications on future air quality policy for NO2 which, until now, has been primarily focused on the emissions from diesel exhausts. [ABSTRACT FROM AUTHOR]

Isoprene and monoterpene emissions to the atmosphere are generally dominated by biogenic sources. The oxidation of these compounds can lead to the production of secondary organic aerosol; however the impact of this chemistry in polluted urban settings has been poorly studied. Isoprene and monoterpenes can form secondary organic aerosol (SOA) heterogeneously via anthropogenic–biogenic interactions, resulting in the formation of organosulfate (OS) and nitrooxy-organosulfate (NOS) species. Delhi, India, is one of the most polluted cities in the world, but little is known about the emissions of biogenic volatile organic compounds (VOCs) or the sources of SOA. As part of the DELHI-FLUX project, gas-phase mixing ratios of isoprene and speciated monoterpenes were measured during pre- and post-monsoon measurement campaigns in central Delhi. Nocturnal mixing ratios of the VOCs were substantially higher during the post-monsoon (isoprene: (0.65±0.43) ppbv; limonene: (0.59±0.11) ppbv; α -pinene: (0.13±0.12) ppbv) than the pre-monsoon (isoprene: (0.13±0.18) ppbv; limonene: 0.011±0.025 (ppbv); α -pinene: 0.033±0.009) period. At night, isoprene and monoterpene concentrations correlated strongly with CO during the post-monsoon period. Filter samples of particulate matter less than 2.5 µm in diameter (PM 2.5) were collected and the OS and NOS content analysed using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS 2). Inorganic sulfate was shown to facilitate the formation of isoprene OS species across both campaigns. Sulfate contained within OS and NOS species was shown to contribute significantly to the sulfate signal measured via AMS. Strong nocturnal enhancements of NOS species were observed across both campaigns. The total concentration of OS and NOS species contributed an average of (2.0±0.9) % and (1.8±1.4) % to the total oxidized organic aerosol and up to a maximum of 4.2 % and 6.6 % across the pre- and post-monsoon periods, respectively. Overall, this study provides the first molecular-level measurements of SOA derived from isoprene and monoterpene in Delhi and demonstrates that both biogenic and anthropogenic sources of these compounds can be important in urban areas. [ABSTRACT FROM AUTHOR]

The photostationary state (PSS) equilibrium between NO and NO 2 is reached within minutes in the atmosphere and can be described by the PSS parameter, φ. Deviations from expected values of φ have previously been used to infer missing oxidants in diverse locations, from highly polluted regions to the extremely clean conditions observed in the remote marine boundary layer (MBL), and have been interpreted as missing understanding of fundamental photochemistry. Here, contrary to these previous observations, we observe good agreement between PSS-derived NO 2 ([NO 2 ] PSSext.), calculated from measured NO, O 3 , and j NO 2 and photochemical box model predictions of peroxy radicals (RO 2 and HO 2), and observed NO 2 ([NO 2 ] Obs.) in extremely clean air containing low levels of CO (<90 ppbV) and VOCs (volatile organic compounds). However, in clean air containing small amounts of aged pollution (CO > 100 ppbV), we observed higher levels of NO 2 than inferred from the PSS, with [NO 2 ] Obs. / [NO 2 ] PSSext. of 1.12–1.68 (25th–75th percentile), implying underestimation of RO 2 radicals by 18.5–104 pptV. Potential NO 2 measurement artefacts have to be carefully considered when comparing PSS-derived NO 2 to observed NO 2 , but we show that the NO 2 artefact required to explain the deviation would have to be ∼ 4 times greater than the maximum calculated from known interferences. If the additional RO 2 radicals inferred from the PSS convert NO to NO 2 with a reaction rate equivalent to that of methyl peroxy radicals (CH 3 O 2), then the calculated net ozone production rate (NOPR, ppbV h -1) including these additional oxidants is similar to the average change in O 3 observed, within estimated uncertainties, once halogen oxide chemistry is accounted for. This implies that such additional peroxy radicals cannot be excluded as a missing oxidant in clean marine air containing aged pollution and that modelled RO 2 concentrations are significantly underestimated under these conditions. [ABSTRACT FROM AUTHOR]

The impact of heterogeneous uptake of HO2 onto aerosol surfaces on radical concentrations and the O3 production regime in Beijing summertime was investigated. The uptake coefficient of HO2 onto aerosol surfaces, γHO2, was calculated for the AIRPRO campaign in Beijing, Summer 2017, as a function of measured aerosol soluble copper concentration, [Cu2+]eff, aerosol liquid water content, [ALWC], and particulate matter concentration, [PM]. An average γHO2 across the entire campaign of 0.070 ± 0.035 was calculated, with values ranging from 0.002 to 0.15, and found to be significantly lower than the value of γHO2=0.2, commonly used in modelling studies. Using the calculated γHO2 values for the Summer AIRPRO campaign, OH, HO2 and RO2 radical concentrations were modelled using a box-model incorporating the Master Chemical Mechanism (v3.3.1), with and without the addition of γHO2, and compared to the measured radical concentrations. Rate of destruction analysis showed the dominant HO2 loss pathway to be HO2 + NO for all NO concentrations across the Summer Beijing campaign with HO2 uptake contributing < 0.3 % to the total loss of HO2 on average. This result for Beijing summertime would suggest that under most conditions encountered, HO2 uptake onto aerosol surfaces is not important to consider when investigating increasing O3 production with decreasing [PM] across the North China Plain. At low [NO], however, i.e. < 0.1 ppb, which was often encountered in the afternoons, up to 29% of modelled HO2 loss was due to HO2 uptake on aerosols when calculated γHO2 was included, even with the much lower γHO2 values compared to γHO2=0.2, a results which agrees with the aerosol-inhibited O3 regime recently proposed by Ivatt et al., 2022. As such it can be concluded that in cleaner environments, away from polluted urban centres where HO2 loss chemistry is not dominated by NO but where aerosol surface area is high still, changes in PM concentration and hence aerosol surface area could still have a significant effect on both overall HO2 concentration and the O3 production regime. Using modelled radical concentrations, the absolute O3 sensitivity to NOx and VOC showed that, on average across the summer AIRPRO campaign, the O3 production regime remained VOC-limited, with the exception of a few days in the afternoon when the NO mixing ratio dropped low enough for the O3 regime to shift towards NOx-limited. The O3 sensitivity to VOC, the dominant regime during the summer AIRPRO campaign, was observed to decrease and shift towards a NOx sensitive regime both when NO mixing ratio decreased and with the addition of aerosol uptake. This suggests that if [NOx] continues to decrease in the future, ozone reduction policies focussing solely on NOx reductions may not be as efficient as expected if [PM] and, hence, HO2 uptake to aerosol surfaces, continues to decrease. The addition of aerosol uptake into the model, for both the γHO2 calculated from measured data and when using a fixed value of γHO2=0.2, did not have a significant effect on the overall O3 production regime across the campaign. While not important for this campaign, aerosol uptake could be important for areas of lower NO concentration that are already in a NOx-sensitive regime. [ABSTRACT FROM AUTHOR]

The ways caregivers perceive and respond to challenging behavior (CB) could depend, in part, on their cultural and ethnic backgrounds. Yet, limited research is available on the definitions, perceptions, and response strategies of CB across cultural groups, particularly among caregivers of young children with disabilities. In this exploratory multimethod study, data were collected from four diverse caregiver groups (i.e., Black, Korean American, Mexican American, and White) with young children with disabilities to understand (a) what behaviors they considered challenging and (b) how they responded to those behaviors. Data revealed similarities and differences in the types of behaviors reported and indicated caregivers rely on preplanned consequence strategies and unplanned responses. [ABSTRACT FROM AUTHOR]

Isoprene nitrates are important chemical species in the atmosphere which contribute to the chemical cycles that form ozone and secondary organic aerosol (SOA) with implications for climate and air quality. Accurate chemical mechanisms are important for the prediction of the atmospheric chemistry of species such as isoprene nitrates in chemical models. In recent years, studies into the chemistry of isoprene nitrates have resulted in the development of a range of mechanisms available for use in the simulation of atmospheric isoprene oxidation. This work uses a 0-D chemical box model to assess the ability of three chemically detailed mechanisms to predict the observed diurnal profiles of four groups of isoprene-derived nitrates in the summertime in the Chinese megacity of Beijing. An analysis of modelled C 5 H 9 NO 5 isomers, including isoprene hydroperoxy nitrate (IPN) species, highlights the significant contribution of non-IPN species to the C 5 H 9 NO 5 measurement, including the potentially large contribution of nitrooxy hydroxyepoxide (INHE). The changing isomer distribution of isoprene hydroxy nitrates (IHNs) derived from OH-initiated and NO 3 -initiated chemistry is discussed, as is the importance of up-to-date alkoxy radical chemistry for the accurate prediction of isoprene carbonyl nitrate (ICN) formation. All mechanisms under-predicted C 4 H 7 NO 5 as predominately formed from the major isoprene oxidation products, methyl vinyl ketone (MVK) and methacrolein (MACR). This work explores the current capability of existing chemical mechanisms to accurately represent isoprene nitrate chemistry in urban areas significantly impacted by anthropogenic and biogenic chemical interactions. It suggests considerations to be taken when investigating isoprene nitrates in ambient scenarios, investigates the potential impact of varying isomer distributions on iodide chemical ionisation mass spectrometry (I - -CIMS) calibrations, and makes some proposals for the future development of isoprene mechanisms. [ABSTRACT FROM AUTHOR]

Fluxes of nitrogen oxides (NOx = NO + NO2) and carbon dioxide (CO2) were measured using eddy covariance at the BT Tower in central London during the coronavirus pandemic. Comparing fluxes to those measured in 2017 prior to the pandemic restrictions and the introduction of the Ultra-Low Emissions Zone (ULEZ) highlighted a 75 % reduction in NOx emissions between the two periods but only a 20 % reduction in CO2 emissions and a 32 % reduction in traffic load. Use of a footprint model and the London Atmospheric Emissions Inventory (LAEI) identified transport and heat and power generation to be the two dominant sources of NOx and CO2 but with significantly different relative contributions for each species. Application of external constraints on NOx and CO2 emissions allowed the reductions in the different sources to be untangled identifying that transport NOx emissions had reduced by > 75 % since 2017. This was attributed in part to the success of air quality policy in central London, but crucially due to the substantial reduction in congestion that resulted from pandemic reduced mobility. Spatial mapping of the fluxes suggests that central London was dominated by point source heat and power generation emissions during the period of reduced mobility. This will have important implications on future air quality policy for NO2 which until now, has been primarily focused on the emissions from diesel exhausts. [ABSTRACT FROM AUTHOR]

Parents of children with autism in low-resource settings have reported exacerbated difficulties related to raising their children. In this single-case research using multiple probe design, four parent mentors and five parent peers and their children with autism in Mongolia participated in the parent peer coaching program. The intervention package, including training and coaching in evidence-based practices, was delivered via telepractice. Parent mentors completed online training and were coached by a bilingual and bicultural research assistant in a staggered fashion. Visual analysis revealed a functional relation between the intervention package and the coaching fidelity of parent mentors. Social validity data indicated that all participants were satisfied with the program and reported it was acceptable, feasible, and effective. Implications for conducting intervention research in a low-resource setting are described. Parents of children with autism are known to experience severe hardships related to raising their children. These hardships are exacerbated in low-resource settings internationally where there is very little resource for children and their families, including professionals who provide evidence-based treatment. Mongolia was chosen as an example of such low-resource settings in this single-case research, and four parent mentors and five parent peers and their children with autism participated and completed the study. A local parent group, the Autism Association of Mongolia, was actively involved in this study and helped with recruitment, development, adaptation, and implementation of the intervention to increase acceptability and feasibility. In addition, a local bilingual research assistant was also utilized as the purpose of this study was to build capacity of diverse stakeholders of children with autism in Mongolia. The research assistant was trained and coached by the research team on both content (communication teaching strategies and behavior management) and delivery (coaching adults), who then provided coaching to parent mentors via live videoconferencing in Mongolian. Parent mentors then similarly provided coaching to parent peers after observing the interactions with their children with autism. The findings suggest that parents can effectively deliver high-fidelity coaching to disseminate evidence-based treatment in low-resource settings when given proper training and coaching. Further examination on scalability and sustainment of effects is suggested. [ABSTRACT FROM AUTHOR]

The importance of family engagement in their children's education and treatment is emphasized by researchers, professional organizations, and legislatures. Providing services with caregivers via telepractice has gained more support and is becoming especially timely due to the current pandemic and social distancing requirements. Professionals, such as board-certified behavior analysts (BCBAs), who work with caregivers with children with disabilities may benefit from receiving professional development on strategies for building better rapport with caregivers and coaching them to bring about maximum clinical efficacy. The current pilot study replicated an earlier study by Meadan et al. to examine the effects of the Coaching Caregiver Professional Development (CoCarePD) intervention package, in which BCBAs received training and coaching from researchers via telepractice, on their caregiver coaching practices. A single-case, multiple-probe design study across three BCBAs was conducted, and findings support a functional relationship between the CoCarePD and BCBAs' use of coaching practices. [ABSTRACT FROM AUTHOR]

Isoprene and monoterpenes emissions to the atmosphere are generally dominated by biogenic sources. The oxidation of these compounds can lead to the production of secondary organic aerosol, however the impact of this chemistry in polluted urban settings has been poorly studied. Isoprene and monoterpenes can form SOA heterogeneously via anthropogenic-biogenic interactions resulting in the formation of organosulfates (OS) and nitrooxy-organosulfates (NOS). Delhi, India is one of the most polluted cities in the world, but little is known about the emissions of biogenic VOCs or the sources of SOA. As part of the DELHI-FLUX project, gas phase mixing ratios of isoprene and speciated monoterpenes were measured during pre- and post-monsoon measurement campaigns in central Delhi. Nocturnal mixing ratios of the VOCs were substantially higher during the post-monsoon (isoprene: (0.65 ± 0.43) ppbv, limonene: (0.59 ± 0.11) ppbv, a-pinene: (0.13 ± 0.12) ppbv) than the pre-monsoon (isoprene: (0.13 ± 0.18) ppbv, limonene: 0.011 ± 0.025 (ppbv), a-pinene: 0.033 ± 0.009) period. At night, isoprene and monoterpene concentrations correlated strongly with CO across during the post-monsoon period. This is one of the first observations in Asia, suggesting monoterpene emissions are dominated by anthropogenic sources. Filter samples of particulate matter less than 2.5 microns in diameter (PM2.5) were collected and the OS and NOS content analysed using ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS2). Inorganic sulfate was shown to facilitate the formation of isoprene OS species across both campaigns. Sulfate contained within OS and NOS species were shown to contribute significantly to the sulfate signal measured via AMS. Strong nocturnal enhancements of NOS species were observed across both campaigns. The total concentration of OS/NOS species contributed an average of (2.0 ± 0.9) % and (1.8 ± 1.4) % to the total oxidised organic aerosol, and up to a maximum of 4.2 % and 6.6 % across the pre- and post-monsoon periods, respectively. Overall, this study provides the first molecular level measurements of SOA derived from isoprene and monoterpene in Delhi and demonstrates that both biogenic and anthropogenic sources of these compounds can be important in urban areas. [ABSTRACT FROM AUTHOR]

During March–June 2017 emissions of nitrogen oxides were measured via eddy covariance at the British Telecom Tower in central London, UK. Through the use of a footprint model the expected emissions were simulated from the spatially resolved National Atmospheric Emissions Inventory for 2017 and compared with the measured emissions. These simulated emissions were shown to underestimate measured emissions during the daytime by a factor of 1.48, but they agreed well overnight. Furthermore, underestimations were spatially mapped, and the areas around the measurement site responsible for differences in measured and simulated emissions were inferred. It was observed that areas of higher traffic, such as major roads near national rail stations, showed the greatest underestimation by the simulated emissions. These discrepancies are partially attributed to a combination of the inventory not fully capturing traffic conditions in central London and both the spatial and temporal resolution of the inventory not fully describing the high heterogeneity of the urban centre. Understanding of this underestimation may be further improved with longer measurement time series to better understand temporal variation and improved temporal scaling factors to better simulate sub-annual emissions. [ABSTRACT FROM AUTHOR]

Challenging behavior exhibited by young children with neurodevelopmental disabilities is known to negatively affect their optimal development and families' quality of life. Although some support exists for English-speaking parents of children with autism who live in high-resource countries, it is scarce for others. Such disparity may also be heightened during the coronavirus disease 2019 (COVID-19) pandemic with its various societal restrictions. To mitigate the treatment gap, we developed and adapted a series of online training modules on behavioral principles and examined its effectiveness with 88 South Korean parents using a randomized controlled trial. We found significant interaction effects on increasing parents' knowledge of behavioral principles, increasing positive parenting practices, and decreasing parental stress. Qualitative social validity data also indicated that parents were highly satisfied with the goals, procedures, and outcomes and that the program positively affected their parenting styles. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are important precursors to the formation of ozone (O3) and secondary organic aerosols (SOA) and can also have direct human health impacts. Generally, given the range and number of VOC species, their emissions are poorly characterised. The VOC levels in Beijing during two campaigns (APHH) were investigated using a dispersion model (NAME), and a chemical box model (AtChem2) in order to understand how chemistry and transport affect the VOC concentrations in Beijing. Emissions of VOCs in Beijing and contributions from outside Beijing were modelled using the NAME dispersion model combined with the emission inventories and were used to initialize the AtChem2 box model. The modelled concentrations of VOCs from the NAME-AtChem2 combination were then compared to the output of a chemical transport model (GEOS-Chem). The results from the emission inventories and the NAME air mass pathways suggest that industrial sources to the south of Beijing and within Beijing both in summer and winter are very important in controlling the VOC levels in Beijing. A number of scenarios with different nitrogen oxides to ozone ratios (NOx/O3) and hydroxyl (OH) levels were simulated to determine the changes in VOC levels. In Beijing over 80% of VOC are emitted locally during winter, while during summer about 35% of VOC concentrations (greater for some individual species) are transported into Beijing from the surrounding regions. Most winter scenarios are in good agreement with daily GEOS-Chem simulations, with the best agreements seen for the modelled concentrations of ethanol, benzene and propane with correlation coefficients of 0.67, 0.63 and 0.64 respectively. Furthermore, the production of formaldehyde within 24 hours air travel from Beijing was investigated, and it was determined that 90% of formaldehyde in the winter and 83% in the summer in Beijing is secondary, produced from oxidation of non-methane volatile organic compounds (NMVOCs). The benzene/CO and toluene/CO ratios during the campaign is very similar to the ratio derived from literature for 2014 in Beijing, however more data are needed to enable investigation of more species over longer timeframes to determine whether this ratio can be applied to predicting VOCs in Beijing. The results suggest that VOC concentrations in Beijing are driven predominantly by sources within Beijing and by local atmospheric chemistry during the winter, and by a combination of transport and chemistry during the summer. Moreover, the relationship of the NOx/VOC and O3 during winter and summer shows the need for season-specific policy measures. [ABSTRACT FROM AUTHOR]

The photostationary state (PSS) equilibrium between NO and NO2 is reached within minutes in the atmosphere and can be described by the PSS parameter, φ. Deviations from expected values of φ have previously been used to infer missing oxidants in diverse locations, from highly polluted regions to the extremely clean conditions observed in the remote marine boundary layer (MBL), and have been interpreted as missing understanding of fundamental photochemistry. Here, contrary to these previous observations, we observe good agreement between PSS-derived NO2 ([NO2]PSS ext.) calculated from photochemical model predictions of peroxy radicals (RO2 and HO2) and measured NO, O3, and jNO2, and observed NO2 in extremely clean air containing low levels of CO (< 90 ppbV) and VOCs. However, in clean air containing small amounts of aged pollution (CO > 100 ppbV), we observed higher levels of NO2 than inferred from the PSS, with [NO2]Obs./[NO2]PSS ext. of 1.12–1.68 (25th–75th percentile) implying 18.5–104 pptV (25th–75th percentile) of missing RO2 radicals. Potential NO2 measurement artefacts have to be carefully considered when comparing PSS-derived NO2 to observed NO2, but we show that the NO2 artefact required to explain the deviation would have to be ~ 4 times greater than the maximum calculated from known interferences. If the missing RO2 radicals have an ozone production efficiency equivalent to that of methyl peroxy radicals (CH3O2), then the calculated net ozone production including these additional oxidants is similar to that observed, within estimated uncertainties, once halogen oxide chemistry is accounted for. This implies that peroxy radicals cannot be excluded as the missing oxidant in clean marine air containing aged pollution, and that measured and modelled RO2 are both significantly underestimated under these conditions. [ABSTRACT FROM AUTHOR]

Isoprene nitrates are important chemical species in the atmosphere which contribute to the chemical cycles that form ozone and secondary organic aerosol (SOA) with implications for climate and air quality. Accurate chemical mechanisms are important for the prediction of the atmospheric chemistry of species such as isoprene nitrates in chemical models. In recent years, studies into the chemistry of isoprene nitrates have resulted in the development of a range of mechanisms available for use in the simulation of atmospheric isoprene oxidation. This work uses a 0-D chemical box-model to assess the ability of three chemically detailed mechanisms to predict the observed diurnal profiles of four groups of isoprene-derived nitrates in the summertime in the Chinese Megacity of Beijing. An analysis of modelled C5H9NO5 isomers, including isoprene hydroperoxy nitrate (IPN) species, highlights the significant contribution of non-IPN species to the C5H9NO5 measurement, including the potentially large contribution of nitrooxy hydroxyepoxide (INHE). The changing isomer distribution of isoprene hydroxy nitrates (IHN) derived from OH-initiated and NO3-initiated chemistry is discussed, as is the importance of up-to-date alkoxy radical chemistry for the accurate prediction of isoprene carbonyl nitrate (ICN) formation. All mechanisms reasonably reproduced C4H7NO5 as predominately formed from the major isoprene oxidation products, methyl vinyl ketone (MVK) and methacrolein (MACR). This work explores the current capability of existing chemical mechanisms to accurately represent isoprene nitrate chemistry in urban areas significantly impacted by anthropogenic and biogenic chemical interactions, suggests considerations to be taken when applying these mechanisms to ambient scenarios, and makes some proposals for the future development of isoprene mechanisms. [ABSTRACT FROM AUTHOR]

OH, HO2, total and partially-speciated RO2, and OH reactivity (k'OH) were measured during the July 2015 ICOZA (Integrated Chemistry of OZone in the Atmosphere) project that took place at a coastal site in North Norfolk, UK. Maximum measured daily OH, HO2, and total RO2 radical concentrations were in the range 2.6-17 × 106, 0.75-4.2 × 108, and 2.3-8.0 × 108 molecule cm-3, respectively. k'OH ranged from 1.7 to 17.6 s-1 with a median value of 4.7 s-1. ICOZA data were split by wind direction to assess differences in the radical chemistry between air that had passed over the North Sea (NW-SE sectors) or major urban conurbations such as London (SW sector). A photostationary steady-state (PSS) calculation underpredicted daytime OH in NW-SE air by ~35%, whereas agreement (~15%) was found within instrumental uncertainty (~26% at 2σ) in SW air. A box model using MCMv3.3.1 chemistry was in better agreement with the OH measurements, but it overpredicted HO2 observations in NW-SE air in the afternoon by a factor of ~2-3, although slightly better agreement was found for HO2 in SW air (factor of ~1.4-2.0 underprediction). The box model severely underpredicted total RO2 observations in both NW-SE and SW air by factors of ~8-9 on average. Measured radical and k'OH levels and measurement-to-model ratios displayed strong dependences on NO mixing ratios. The PSS calculation could capture OH observations at high NO but underpredicted the observations at low NO. The box model overpredicted HO2 concentrations at low NO in NW-SE air, whereas in SW air, the measurements and model results were in agreement across the full NO range. The box model underpredicted total RO2 at all NO levels, where the measurement-to-model ratio scaled with NO. This trend has been found in all previous field campaigns in which total RO2 was measured using the ROxLIF technique and suggests that peroxy radical chemistry is not well understood under high NOx conditions. [ABSTRACT FROM AUTHOR]

In our companion paper (Woodward-Massey et al., 2022), we presented measurements of radical species and OH reactivity (k'OH) made in summer 2015 during the ICOZA (Integrated Chemistry of OZone in the Atmosphere) field campaign at the Weybourne Atmospheric Observatory, a site on the east coast of the UK. In the present work, we used the simultaneous measurement of OH, HO2, total RO2, and k'OH to derive experimental (i.e., observationally determined) budgets for all radical species as well as total ROx (= OH + HO2 + RO2). Data were separated according to wind direction: prevailing SW winds (with influence from London and other major conurbations), and all other winds (NW-SE; predominantly marine in origin). In NW-SE air, the ROx budget could be closed during the daytime within experimental uncertainty but OH destruction exceeded OH production, and HO2 production greatly exceeded HO2 destruction while the opposite was true for RO2. In SW air, the ROx budget analysis indicated missing daytime ROx sources but the OH budget was balanced, and the same imbalances were found with the HO2 and RO2 budgets as in NW-SE air. For HO2 and RO2, the budget imbalances were most severe at high NO mixing ratios. We explored several mechanistic modifications to the experimental budgets to try to reconcile the HO2 and RO2 budget imbalances: (1) the addition of generic radical recycling processes, (2) reduction of the rate of RO2 x HO2 conversion, (3) inclusion of heterogeneous HO2 uptake, and (4) addition of chlorine chemistry. The best agreement between HO2 and RO2 production and destruction rates was found for option (2), in which we reduced the RO2 + NO rate constant by a factor of 5. The rate of in situ ozone production (P(Ox)) was calculated from observations of ROx, NO, and NO2 and compared to that calculated from MCM-modelled radical concentrations. The MCM-calculated P(Ox) significantly 35 underpredicted the measurement-calculated P(Ox) in the morning, and the degree of underprediction was found to scale with NO. [ABSTRACT FROM AUTHOR]

The oil and gas (O&G) sector is a significant source of methane (CH4) emissions. Quantifying these emissions remains challenging, with many studies highlighting discrepancies between measurements and inventory-based estimates. In this study, we present CH4 emission fluxes from 21 offshore O&G facilities collected in 10 O&G fields over two regions of the Norwegian continental shelf in 2019. Emissions of CH4 derived from measurements during 13 aircraft surveys were found to range from 2.6 to 1200 tyr-1 (with a mean of 211 tyr-1 across all 21 facilities). Comparing this with aggregated operator-reported facility emissions for 2019, we found excellent agreement (within 1 σ uncertainty), with mean aircraft-measured fluxes only 16 % lower than those reported by operators. We also compared aircraft-derived fluxes with facility fluxes extracted from a global gridded fossil fuel CH4 emission inventory compiled for 2016. We found that the measured emissions were 42 % larger than the inventory for the area covered by this study, for the 21 facilities surveyed (in aggregate). We interpret this large discrepancy not to reflect a systematic error in the operator-reported emissions, which agree with measurements, but rather the representativity of the global inventory due to the methodology used to construct it and the fact that the inventory was compiled for 2016 (and thus not representative of emissions in 2019). This highlights the need for timely and up-to-date inventories for use in research and policy. The variable nature of CH4 emissions from individual facilities requires knowledge of facility operational status during measurements for data to be useful in prioritising targeted emission mitigation solutions. Future surveys of individual facilities would benefit from knowledge of facility operational status over time. Field-specific aggregated emissions (and uncertainty statistics), as presented here for the Norwegian Sea, can be meaningfully estimated from intensive aircraft surveys. However, field-specific estimates cannot be reliably extrapolated to other production fields without their own tailored surveys, which would need to capture a range of facility designs, oil and gas production volumes, and facility ages. For year-on-year comparison to annually updated inventories and regulatory emission reporting, analogous annual surveys would be needed for meaningful top-down validation. In summary, this study demonstrates the importance and accuracy of detailed, facility-level emission accounting and reporting by operators and the use of airborne measurement approaches to validate bottom-up accounting. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this review article was to (a) scope the literature related to coaching caregivers of children with autism to provide an overview of current practices for assessment and intervention conducted via telepractice in collaboration with caregivers and (b) examine commonly reported challenges related to telepractice and potential solutions. Method: We conducted a search of relevant literature and identified seven articles that are related to the topic of caregiver involvement in remote assessments and interventions for children with autism. Results: Seven studies that include 10 caregiver-implemented interventions were identified. Researchers have used telepractice to conduct both assessments and interventions, and they generally reported having successful interactions with caregivers using different telepractice platforms. The most common telepractice modality was conducting live videoconferencing to provide services. These articles also contained rich information related to the commonly reported barriers and needs of caregivers to conduct telepractice, such as challenges in using telepractice technology and providing adequate training to caregivers. The studies also address different strategies researchers and professionals may utilize to alleviate these practical challenges to provide more streamlined tele-practice services. Conclusions: Although there are challenges related to conducting assessments and interventions via telepractice, it was suggested that telepractice can be a supplement in delivering evidence-based interventions. As there are implications for future research and practice, we call for more research and practice to examine how professionals may optimize service delivery to caregivers. [ABSTRACT FROM AUTHOR]

Arctic wetlands and surrounding ecosystems are both a significant source of methane (CH4) and a sink of carbon dioxide (CO2) during summer months. However, precise quantification of this regional CH4 source and CO2 sink remains poorly characterized. A research flight using the UK Facility for Airborne Atmospheric Measurement was conducted in July 2019 over an area (approx. 78 000km2) of mixed peatland and forest in northern Sweden and Finland. Area-averaged fluxes of CH4 and carbon dioxide were calculated using an aircraft mass balance approach. Net CH4 fluxes normalized to wetland area ranged between 5.93±1.87mgm-2 h-1 and 4.44±0.64mgm-2 h-1 (largest to smallest) over the region with a meridional gradient across three discrete areas enclosed by the flight survey. From largest to smallest, net CO2 sinks ranged between -513±74mgm-2 h-1 and -284±89mgm-2 h-1 and result from net uptake of CO2 by vegetation and soils in the biosphere. A clear gradient of decreasing bulk and area-averaged CH4 flux was identified from north to south across the study region, correlated with decreasing peat bog land area from north to south identified from CORINE land cover classifications. While N2O mole fraction was measured, no discernible gradient was measured over the flight track, but a minimum flux threshold using this mass balance method was calculated. Bulk (total area) CH4 fluxes determined via mass balance were compared with area-weighted upscaled chamber fluxes from the same study area and were found to agree well within measurement uncertainty. The mass balance CH4 fluxes were found to be significantly higher than the CH4 fluxes reported by many land-surface process models compiled as part of the Global Carbon Project. There was high variability in both flux distribution and magnitude between the individualmodels. This further supports previous studies that suggest that land-surface models are currently ill-equipped to accurately capture carbon fluxes in the region. [ABSTRACT FROM AUTHOR]

We report methane isotopologue data from aircraft and ground measurements in Africa and South America. Aircraft campaigns sampled strong methane fluxes over tropical papyrus wetlands in the Nile, Congo and Zambezi basins, herbaceous wetlands in Bolivian southern Amazonia, and over fires in African woodland, cropland and savannah grassland. Measured methane δ13CCH4 isotopic signatures were in the range -55 to -49‰ for emissions from equatorial Nile wetlands and agricultural areas, but widely -60±1‰ from Upper Congo and Zambezi wetlands. Very similar δ13CCH4 signatures were measured over the Amazonian wetlands of NE Bolivia (around -59‰) and the overall δ13CCH4 signature from outer tropical wetlands in the southern Upper Congo and Upper Amazon drainage plotted together was -59±2‰. These results were more negative than expected. For African cattle, δ13CCH4 values were around -60 to -50‰. Isotopic ratios in methane emitted by tropical fires depended on the C3:C4 ratio of the biomass fuel. In smoke from tropical C3 dry forest fires in Senegal, δ13CCH4 values were around -28‰. By contrast, African C4 tropical grass fire δ13CCH4 values were -16 to -12‰. Methane from urban landfills in Zambia and Zimbabwe, which have frequent waste fires, had δ13CCH4 around -37 to -36‰. These new isotopic values help improve isotopic constraints on global methane budget models because atmospheric δ13CCH4 values predicted by global atmospheric models are highly sensitive to the δ13CCH4 isotopic signatures applied to tropical wetland emissions. Field and aircraft campaigns also observed widespread regional smoke pollution over Africa, in both the wet and dry seasons, and large urban pollution plumes. The work highlights the need to understand tropical greenhouse gas emissions in order to meet the goals of the UNFCCC Paris Agreement, and to help reduce air pollution over wide regions of Africa. [ABSTRACT FROM AUTHOR]

During March - June 2017 emissions of nitrogen oxides were measured via eddy covariance at the British Telecom Tower in central London, UK. Through the use of a footprint model the expected emissions were simulated from the spatially resolved National Atmospheric Emissions Inventory for 2017, and compared with the measured emissions. These simulated emissions were shown to underestimate measured emissions during the day time by a factor of 1.48, but they agreed well overnight. Furthermore, underestimations were spatially mapped and the areas around the measurement site responsible for differences in measured and simulated emissions inferred. It was observed that areas of higher traffic, such as major roads near national rail stations, showed the greatest underestimation by the simulated emissions. These discrepancies are partially attributed to a combination of the inventory not fully capturing traffic conditions in central London, and both spatial and temporal resolution of the inventory not fully describing the high heterogeneity of the urban centre. Understanding of this underestimation may further improved with longer measurement time series,to better understand temporal variation, and improved temporal scaling factors, to better simulate sub-annual emissions. [ABSTRACT FROM AUTHOR]

Nitrous acid, HONO , is a key net photolytic precursor to OH radicals in the atmospheric boundary layer. As OH is the dominant atmospheric oxidant, driving the removal of many primary pollutants and the formation of secondary species, a quantitative understanding of HONO sources is important to predict atmospheric oxidising capacity. While a number of HONO formation mechanisms have been identified, recent work has ascribed significant importance to the dark, ocean-surface-mediated conversion of NO2 to HONO in the coastal marine boundary layer. In order to evaluate the role of this mechanism, here we analyse measurements of HONO and related species obtained at two contrasting coastal locations – Cabo Verde (Atlantic Ocean, denoted Cape Verde herein), representative of the clean remote tropical marine boundary layer, and Weybourne (United Kingdom), representative of semi-polluted northern European coastal waters. As expected, higher average concentrations of HONO (70 ppt) were observed in marine air for the more anthropogenically influenced Weybourne location compared to Cape Verde (HONO < 5 ppt). At both sites, the approximately constant HONO/NO2 ratio at night pointed to a low importance for the dark, ocean-surface-mediated conversion of NO2 into HONO , whereas the midday maximum in the HONO/NO2 ratios indicated significant contributions from photo-enhanced HONO formation mechanisms (or other sources). We obtained an upper limit to the rate coefficient of dark, ocean-surface HONO -to- NO2 conversion of CHONO = 0.0011 ppb h -1 from the Cape Verde observations; this is a factor of 5 lower than the slowest rate reported previously. These results point to significant geographical variation in the predominant HONO formation mechanisms in marine environments and indicate that caution is required when extrapolating the importance of such mechanisms from individual study locations to assess regional and/or global impacts on oxidising capacity. As a significant fraction of atmospheric processing occurs in the marine boundary layer, particularly in the tropics, better constraint of the possible ocean surface source of HONO is important for a quantitative understanding of chemical processing of primary trace gases in the global atmospheric boundary layer and associated impacts upon air pollution and climate. [ABSTRACT FROM AUTHOR]

The oil and gas (O&G) sector is a significant source of methane (CH4) emissions. Quantifying these emissions remains challenging, with many studies highlighting discrepancies between measurements and inventory-based estimates. In this study, we present CH[sub 4] emission fluxes from 21 offshore O&G facilities collected in 10 O&G fields over two regions of the Norwegian Continental Shelf in 2019. Emissions of CH4 derived from measurements during 13 aircraft surveys were found to range from 2.6 to 1200 t year-1 (with a mean of 211 t year-1 across all 21 facilities). Comparing this with aggregated operator-reported facility emissions for 2019, we found excellent agreement (within 1σ uncertainty), with mean aircraft-measured fluxes 16% lower than those reported by operators. We also compared aircraft-derived fluxes with facility fluxes extracted from a global gridded fossil fuel CH4 emission inventory compiled for 2016. We found that the measured emissions were 42% larger than the inventory for the area covered by this study, for the 21 facilities surveyed (in aggregate). We interpret this large discrepancy not to reflect a systematic error in the operator-reported emissions, which agree with measurements, but rather the representivity of the global inventory due to the methodology used to construct it and the fact that the inventory was compiled for 2016 (and thus not representative of emissions in 2019). This highlights the need for timely and up-to-date inventories for use in research and policy. The variable nature of CH4 emissions from individual facilities requires knowledge of facility operational status during measurements for data to be useful in prioritizing targeted emission mitigation solutions. Surveys of individual facilities may always require this. However, for field-aggregated emissions, our results show that an accurate estimate of total field-level emissions simply requires a sufficiently large and representative sample of facilities, to yield meaningful comparisons and flux statistics, irrespective of operational status information. In summary, this study demonstrates the importance and accuracy of detailed, facility-level emission accounting and reporting by operators and the use of measurement approaches to validate bottom-up accounting. [ABSTRACT FROM AUTHOR]

Flux measurements of nitrogen oxides (NO x) were made over London using airborne eddy covariance from a low-flying aircraft. Seven low-altitude flights were conducted over Greater London, performing multiple overpasses across the city during eight days in July 2014. NO x fluxes across the Greater London region (GLR) exhibited high heterogeneity and strong diurnal variability, with central areas responsible for the highest emission rates (20–30 mg m -2 h -1). Other high-emission areas included the M25 orbital motorway. The complexity of London's emission characteristics makes it challenging to pinpoint single emissions sources definitively using airborne measurements. Multiple sources, including road transport and residential, commercial and industrial combustion sources, are all likely to contribute to measured fluxes. Measured flux estimates were compared to scaled National Atmospheric Emissions Inventory (NAEI) estimates, accounting for monthly, daily and hourly variability. Significant differences were found between the flux-driven emissions and the NAEI estimates across Greater London, with measured values up to 2 times higher in Central London than those predicted by the inventory. To overcome the limitations of using the national inventory to contextualise measured fluxes, we used physics-guided flux data fusion to train environmental response functions (ERFs) between measured flux and environmental drivers (meteorological and surface). The aim was to generate time-of-day emission surfaces using calculated ERF relationships for the entire GLR; 98 % spatial coverage was achieved across the GLR at 400 m 2 spatial resolution. All flight leg projections showed substantial heterogeneity across the domain, with high emissions emanating from Central London and major road infrastructure. The diurnal emission structure of the GLR was also investigated, through ERF, with the morning rush hour distinguished from lower emissions during the early afternoon. Overall, the integration of airborne fluxes with an ERF-driven strategy enabled the first independent generation of surface NO x emissions, at high resolution using an eddy-covariance approach, for an entire city region. [ABSTRACT FROM AUTHOR]

Although it is well-documented that families of children with autism in developed nations report hardships, few researchers have focused on families who live in less-developed, low-resource settings. Using five focus groups with 30 parents of children with autism in Mongolia, a low- resource setting, the purpose of this study was to provide detailed accounts of their experiences, challenges, and needs. Participants reported severe challenges related to raising their children with autism in their country. Parents shared barriers related to the limited availability of services and support, exacerbated financial burdens, and a lack of enforcement of relevant laws. Parents also shared their perceived needs including more services for their children, more sustainable training and coaching programs for parents, and parents' collective advocacy. [ABSTRACT FROM AUTHOR]

Family systems are dynamic and interconnected, yet very limited research has considered both fathers' and mothers' perceptions of family support, stress and Family Quality of Life (FQOL) in a dynamic manner, especially in the Chinese context. The current study examines the association between parenting stress, FQOL and family support using a dyadic approach. We employed the actor-partner interdependence mediation model (APIMeM) to analyze a sample (N = 219 dyads) of Chinese fathers' and mothers' of children with autism spectrum disorder. Results suggested a strong actor effect of family support on decreasing stress and improving FQOL for mother and father respectively. However, the partner effect was largely contrasted with mothers' perceived family support and positively associated with fathers' FQOL, and fathers' perceived family support negatively associated with mothers' FQOL. There were no mediating effects of stress on partners' perceived support on FQOL. Despite being in a family system, the contrast pattern (opposite direction of the effects) between mothers and fathers suggest large discrepancies and perceptions, which may be due to different family roles and parenting involvement. Policy and practical implications are provided. [ABSTRACT FROM AUTHOR]

Parent advocacy has led to improved educational access and outcomes for students with disabilities. Extant research indicates that parents are more likely to participate in individual advocacy than systemic advocacy. Due to the preponderance of individual advocacy, limited research has focused on systemic advocacy. Thus, the purpose of this study was to explore individual and systemic advocacy among parents of children with disabilities. Prior to attending a training on civic engagement, 127 parents from four states participated in English- or Spanish-speaking focus groups. Results indicated participants more frequently engaged in individual advocacy than systemic advocacy and utilized a greater variety of individual advocacy strategies. Additionally, parent advocacy can be developmental, moving from individual to systemic efforts. Participants also identified barriers and facilitators impacting their systemic and individual advocacy. Implications for future research and practice are discussed. [ABSTRACT FROM AUTHOR]

Strict seasonal emission controls are a popular measure in China for addressing severe air pollution, in particular fine particulate matter (PM2.5). Here we evaluate the efficacy of these measures, with a particular focus on the strict emission controls imposed on pollution sources in 28 cities in and around the Beijing-Tianjin-Hebei region (BTH) in autumn-winter 2017/2018. For this we use the GEOS-Chem chemical transport model and air pollutant measurements from the national and Beijing local monitoring networks, after evaluating the network data with independent measurements and correcting large biases in the bottom-up emissions inventory. The network measurements are temporally consistent (r > 0.9 for PM2.5 and r > 0.7 for gases) with the independent measurements, though with systematic differences of 5-17% for nitrogen dioxide (NO2) and 16-28% for carbon monoxide (CO). The average decrease in monitoring network PM2.5 in BTH in autumn-winter 2017/2018 relative to the previous year is 27%, declining from 103 to 75 μg m-3. The regional decline in PM2.5 in the model is 20%, exceeding the regional target of 15%. According to the model, pollution control measures led to decline in PM2.5 precursor emissions of 0.27 Tg NOx (as NO), 0.66 Tg sulfur dioxide (SO2), 70 Gg organic carbon (OC), and 50 Gg black carbon (BC). We find though that these alone only lead to an 8% decline in PM2.5 and that interannual variability in meteorology accounts for more than half (57%) the decline. This demonstrates that year-on-year comparisons are misleading for assessing the efficacy of air pollution measures and should be taken into consideration when extending such measures beyond BTH. [ABSTRACT FROM AUTHOR]

Nitrous acid, HONO, is a key net photolytic precursor to OH radicals in the atmospheric boundary later. As OH is the dominant atmospheric oxidant, driving the removal of many primary pollutants and the formation of secondary species, a quantitative understanding of HONO sources is important to predict atmospheric oxidising capacity. While a number of HONO formation mechanisms have been identified, recent work has ascribed significant importance to the dark, oceansurface mediated conversion of NO2 to HONO in the coastal marine boundary layer. In order to evaluate the role of this mechanism, here we analyse measurements of HONO and related species obtained at two contrasting coastal locations - Cape Verde (Atlantic Ocean), representative of the clean remote tropical marine boundary layer, and Weybourne (United Kingdom), representative of semi-polluted Northern European coastal waters. As expected, higher average concentrations of HONO (70 ppt) were observed in marine air for the more anthropogenically influenced Weybourne location compared to Cape Verde (HONO <5 ppt). At both sites, the approximately constant HONO/NO 2 ratio at night pointed to a low importance for the dark ocean-surface mediated conversion of NO2 into HONO, whereas the midday maximum in the HONO/NO2 ratios indicated significant contributions from photo-enhanced HONO formation mechanisms (or other sources). We obtained an upper limit to the rate coefficient of dark ocean-surface HONO-to-NO2 conversion of CHONO = 0.0011 ppb hr-1 from the Cape Verde observations; this is a factor of 5 lower than the slowest rate reported previously. These results point to significant geographical variation in the predominant HONO formation mechanisms in marine environments and indicate that caution is required when extrapolating the importance of such mechanisms from individual study locations to assess regional and/or global impacts on oxidising capacity. As a significant fraction of atmospheric processing occurs in the marine boundary layer, particularly in the tropics, better constraint of the possible ocean surface source of HONO is important for a quantitative understanding of chemical processing of primary trace gases in the global atmospheric boundary layer and associated impacts upon air pollution and climate. [ABSTRACT FROM AUTHOR]

Although the Individuals With Disabilities Education Improvement Act (IDEA) mandates parent participation in their children's education programs, the implementation of IDEA results in parent effort beyond participation, specifically, an expectation of advocacy. To date, research on the advocacy expectation is mixed, with some parents perceiving advocacy as an obligation to ensure appropriate services for their children, whereas others argue it is unreasonable and has cultural dissonance, disadvantaging some parents. We examined parent perspectives of the advocacy expectation in special education through 19 focus groups with 127 parents of children with disabilities across four states. Findings included a nuanced understanding of the advocacy expectation, with participants reporting the importance of advocacy and some describing that advocacy was part of their social role. However, under adversarial circumstances with school personnel, participants described feeling overwhelmed because the advocacy expectation felt more difficult than it needed to be. We discuss implications for policy and practice. [ABSTRACT FROM AUTHOR]

Isoprene is the most important biogenic volatile organic compound in the atmosphere. Its calculated impact on ozone (O 3) is critically dependent on the model isoprene oxidation chemical scheme, in particular the way the isoprene-derived organic nitrates (IN) are treated. By combining gas chromatography with mass spectrometry, we have developed a system capable of separating and unambiguously measuring individual IN isomers. In this paper we use measurements from its first field deployment, which took place in Beijing as part of the Atmospheric Pollution and Human Health in a Chinese Megacity programme, to test understanding of the isoprene chemistry as simulated in the Master Chemical Mechanism (MCM) (v.3.3.1). Seven individual isoprene nitrates were identified and quantified during the campaign: two β -hydroxy nitrates (IHN), four δ -carbonyl nitrates (ICN), and propanone nitrate. Our measurements show that in the summertime conditions experienced in Beijing the ratio of (1-OH, 2-ONO 2)-IHN to (4-OH, 3-ONO 2)-IHN (the numbers indicate the carbon atom in the isoprene chain to which the radical is added) increases at NO mixing ratios below 2 ppb. This provides observational field evidence of the redistribution of the peroxy radicals derived from OH oxidation of isoprene away from the kinetic ratio towards a new thermodynamic equilibrium consistent with box model calculations. The observed amounts of δ -ICN demonstrate the importance of daytime addition of NO 3 to isoprene in Beijing but suggest that the predominant source of the δ -ICN in the model (reaction of NO with δ -nitrooxy peroxy radicals) may be too large. Our speciated measurements of the four δ -ICN exhibit a mean C1 : C4 isomer ratio of 1.4 and a mean trans : cis isomer ratio of 7 and provide insight into the isomeric distribution of the δ -nitrooxy peroxy radicals. Together our measurements and model results indicate that propanone nitrate was formed from the OH oxidation of δ -ICN both during the day and night, as well as from NO 3 addition to propene at night. This study demonstrates the value of speciated IN measurements in testing understanding of the isoprene degradation chemistry and shows how more extensive measurements would provide greater constraints. It highlights areas of the isoprene chemistry that warrant further study, in particular the impact of NO on the formation of the IHN and the NO 3 -initiated isoprene degradation chemistry, as well as the need for further laboratory studies on the formation and the losses of IN, in particular via photolysis of δ -ICN and hydrolysis. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen oxides (NO + NO 2 = NO x) have been measured at the Cape Verde Atmospheric Observatory (CVAO) in the tropical Atlantic (16 ∘ 51 ′ N, 24 ∘ 52 ′ W) since October 2006. These measurements represent a unique time series of NO x in the background remote troposphere. Nitrogen dioxide (NO 2) is measured via photolytic conversion to nitric oxide (NO) by ultraviolet light-emitting diode arrays followed by chemiluminescence detection. Since the measurements began, a blue light converter (BLC) has been used for NO 2 photolysis, with a maximum spectral output of 395 nm from 2006 to 2015 and of 385 nm from 2015 onwards. The original BLC used was constructed with a Teflon-like material and appeared to cause an overestimation of NO 2 when illuminated. To avoid such interferences, a new additional photolytic converter (PLC) with a quartz photolysis cell (maximum spectral output also 385 nm) was implemented in March 2017. Once corrections are made for the NO 2 artefact from the original BLC, the two NO 2 converters are shown to give comparable NO 2 mixing ratios (BLC = 0.99 × PLC + 0.7 ppt, linear least-squares regression), giving confidence in the quantitative measurement of NO x at very low levels. Data analysis methods for the NO x measurements made at CVAO have been developed and applied to the entire time series to produce an internally consistent and high-quality long-term data set. NO has a clear diurnal pattern with a maximum mixing ratio of 2–10 ppt during the day depending on the season and ∼ 0 ppt during the night. NO 2 shows a fairly flat diurnal signal, although a small increase in daytime NO x is evident in some months. Monthly average mixing ratios of NO 2 vary between 5 and 30 ppt depending on the season. Clear seasonal trends in NO and NO 2 levels can be observed with a maximum in autumn and winter and a minimum in spring and summer. [ABSTRACT FROM AUTHOR]