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Aerosol absorption of visible light has an important impact on global radiative forcing. Wildfires are one of the major sources of light-absorbing aerosol, but there remains significant uncertainty about the magnitude, wavelength dependence, and bleaching of absorption from biomass burning aerosol. We collected and analyzed data from 21 western US wildfire smoke plumes during the 2018 Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption and Nitrogen (WE-CAN) airborne measurement campaign to determine the contribution of black carbon (BC), brown carbon (BrC), and lensing to the aerosol mass absorption cross section (MAC). Comparison to commonly used parameterizations and modeling studies suggests that model overestimation of absorption is likely due to incorrect BrC refractive indices. Modelers (Wang et al., 2018; Carter et al., 2021) invoke a bleaching process that decreases the MAC of organic aerosol (OA) to offset the overestimation of absorption in models. However, no evidence of a decreasing MAC is observed in individual WE-CAN fire plumes or in aged plumes from multiple fires. A decrease in OA mass and water-soluble organic carbon (WSOC), both normalized by carbon monoxide (CO) to correct for dilution, is observed with an increasing oxygen-to-carbon (O : C) ratio and a decreasing gas-phase toluene : benzene ratio, when data from all fires are combined in half of the individual fire plumes. This results in a strong decrease in total absorption at 405 nm and a slight decrease at 660 nm with these chemical markers. These results demonstrate that changes in absorption with chemical markers of plume age are the result of decreasing OA rather than changes in the MAC of the organic material itself. While decreasing MAC or OA mass with aging could both be called bleaching and can both correct overestimation of absorption in models, it is important to distinguish between these two effects because decreasing OA mass will also decrease scattering, which will cause a significantly different net radiative effect. We also find that an average of 54 % of non-BC absorption (23 % total absorption) at 660 nm is from water-soluble BrC, confirming that BrC absorption is important across the visible spectrum. Quantification of significant BrC at red wavelengths and observation of bleaching being caused by changes in OA with O : C and toluene : benzene markers of plume age provide important improvements to our understanding of BrC and critical constraints on aerosol absorption in regional and global climate models.

The impact of biomass burning (BB) on the atmospheric burden of volatile organic compounds (VOCs) is highly uncertain. Here we apply the GEOS-Chem chemical transport model (CTM) to constrain BB emissions in the western USA at ∼ 25 km resolution. Across three BB emission inventories widely used in CTMs, the inventory–inventory comparison suggests that the totals of 14 modeled BB VOC emissions in the western USA agree with each other within 30 %–40 %. However, emissions for individual VOCs can differ by a factor of 1–5, driven by the regionally averaged emission ratios (ERs, reflecting both assigned ERs for specific biome and vegetation classifications) across the three inventories. We further evaluate GEOS-Chem simulations with aircraft observations made during WE-CAN (Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption and Nitrogen) and FIREX-AQ (Fire Influence on Regional to Global Environments and Air Quality) field campaigns. Despite being driven by different global BB inventories or applying various injection height assumptions, the model–observation comparison suggests that GEOS-Chem simulations underpredict observed vertical profiles by a factor of 3–7. The model shows small to no bias for most species in low-/no-smoke conditions. We thus attribute the negative model biases mostly to underestimated BB emissions in these inventories. Tripling BB emissions in the model reproduces observed vertical profiles for primary compounds, i.e., CO, propane, benzene, and toluene. However, it shows no to less significant improvements for oxygenated VOCs, particularly for formaldehyde, formic acid, acetic acid, and lumped ≥ C3 aldehydes, suggesting the model is missing secondary sources of these compounds in BB-impacted environments. The underestimation of primary BB emissions in inventories is likely attributable to underpredicted amounts of effective dry matter burned, rather than errors in fire detection, injection height, or ERs, as constrained by aircraft and ground measurements. We cannot rule out potential sub-grid uncertainties (i.e., not being able to fully resolve fire plumes) in the nested GEOS-Chem which could explain the negative model bias partially, though back-of-the-envelope calculation and evaluation using longer-term ground measurements help support the argument of the dry matter burned underestimation. The total ERs of the 14 BB VOCs implemented in GEOS-Chem only account for half of the total 161 measured VOCs (∼ 75 versus 150 ppb ppm−1). This reveals a significant amount of missing reactive organic carbon in widely used BB emission inventories. Considering both uncertainties in effective dry matter burned (× 3) and unmodeled VOCs (× 2), we infer that BB contributed to 10 % in 2019 and 45 % in 2018 (240 and 2040 Gg C) of the total VOC primary emission flux in the western USA during these two fire seasons, compared to only 1 %–10 % in the standard GEOS-Chem.

Light absorbing organic carbon, or brown carbon (BrC), can be a significant contributor to the visible light absorption budget. However, the sources of BrC and the contributions of BrC to light absorption are not well understood. Biomass burning is thought to be a major source of BrC. Therefore, as part of the WE-CAN (Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption and Nitrogen) study, BrC absorption data were collected on board the National Science Foundation/National Center for Atmospheric Research (NSF/NCAR) C-130 aircraft as it intercepted smoke from wildfires in the western US in July–August 2018. BrC absorption measurements were obtained in near real-time using two techniques. The first coupled a particle-into-liquid sampler (PILS) with a liquid waveguide capillary cell and a total organic carbon analyzer for measurements of water-soluble BrC absorption and WSOC (water-soluble organic carbon). The second employed a custom-built photoacoustic aerosol absorption spectrometer (PAS) to measure total absorption at 405 and 660 nm. The PAS BrC absorption at 405 nm (PAS total Abs 405 BrC) was calculated by assuming the absorption determined by the PAS at 660 nm was equivalent to the black carbon (BC) absorption and the BC aerosol absorption Ångström exponent was 1. Data from the PILS and PAS were combined to investigate the water-soluble vs. total BrC absorption at 405 nm in the various wildfire plumes sampled during WE-CAN. WSOC, PILS water-soluble Abs 405, and PAS total Abs 405 tracked each other in and out of the smoke plumes. BrC absorption was correlated with WSOC (R2 value for PAS =0.42 and PILS =0.60) and CO (carbon monoxide) (R2 value for PAS =0.76 and PILS =0.55) for all wildfires sampled. The PILS water-soluble Abs 405 was corrected for the non-water-soluble fraction of the aerosol using the calculated UHSAS (ultra-high-sensitivity aerosol spectrometer) aerosol mass. The corrected PILS water-soluble Abs 405 showed good closure with the PAS total Abs 405 BrC with a factor of ∼1.5 to 2 difference. This difference was explained by particle vs. bulk solution absorption measured by the PAS vs. PILS, respectively, and confirmed by Mie theory calculations. During WE-CAN, ∼ 45 % (ranging from 31 % to 65 %) of the BrC absorption was observed to be due to water-soluble species. The ratio of BrC absorption to WSOC or ΔCO showed no clear dependence on fire dynamics or the time since emission over 9 h.

Brown carbon (BrC) consists of particulate organic species that preferentially absorb light at visible and ultraviolet wavelengths. Ambient studies show that as a component of aerosol particles, BrC affects photochemical reaction rates and regional to global climate. Some organic chromophores are especially toxic, linking BrC to adverse health effects. The lack of direct measurements of BrC has limited our understanding of its prevalence, sources, evolution, and impacts. We describe the first direct, online measurements of water-soluble BrC on research aircraft by three separate instruments. Each instrument measured light absorption over a broad wavelength range using a liquid waveguide capillary cell (LWCC) and grating spectrometer, with particles collected into water by a particle-into-liquid sampler (CSU PILS-LWCC and NOAA PILS-LWCC) or a mist chamber (MC-LWCC). The instruments were deployed on the NSF C-130 aircraft during WE-CAN 2018 as well as the NASA DC-8 and the NOAA Twin Otter aircraft during FIREX-AQ 2019, where they sampled fresh and moderately aged wildfire plumes. Here, we describe the instruments, calibrations, data analysis and corrections for baseline drift and hysteresis. Detection limits (3σ) at 365 nm were 1.53 Mm−1 (MC-LWCC; 2.5 min sampling time), 0.89 Mm−1 (CSU PILS-LWCC; 30 s sampling time), and 0.03 Mm−1 (NOAA PILS-LWCC; 30 s sampling time). Measurement uncertainties were 28 % (MC-LWCC), 12 % (CSU PILS-LWCC), and 11 % (NOAA PILS-LWCC). The MC-LWCC system agreed well with offline measurements from filter samples, with a slope of 0.91 and R2=0.89. Overall, these instruments provide soluble BrC measurements with specificity and geographical coverage that is unavailable by other methods, but their sensitivity and time resolution can be challenging for aircraft studies where large and rapid changes in BrC concentrations may be encountered.

Formative assessment has become a focus of classroom teachers as a quick method to assess students' progress in their classrooms. For students to be prepared for summative assessments, it is important to separate the traditional forms of summative assessment from the everyday practice and feedback that is formative assessment. Mathematics teachers can modify current classroom processes to meet the qualities of true formative assessment and, in the process, improve student learning through engagement.

Background: Evidence-based practice (EBP) is supported by the appropriate use of standardized outcome measures (OMs). Continuing education (CE) is a common method for translation of OMs knowledge to practice. However, little is known about the attitudes and behaviors of physical therapists regarding CE and knowledge translation (KT) of OMs. Purpose: To determine physical therapists' practice style traits (PSTs) and compare these to attitudes, knowledge, behaviors, and barriers for KT. Subjects and Methods: Seventy-nine physical therapists who attended a CE course on OMs completed two standardized surveys. The Practice Style Questionnaire (PSQ) categorizes responses on three theoretical constructs: 1. how clinician weighs research evidence versus experience, 2. their degree of comfort in clinical practice, and 3. how evidence impacts their workload. The EBP Questionnaire (EBPQ) items are grouped into four domains: attitude, knowledge, behavior, and barriers. Results: On the PSQ, 28% of subjects were categorized as "seekers" of evidence, 49% were "pragmatists," and 23% were "receptives." PSTs scores were compared to the four domains of the EBPQ. Behavior was the only domain found to be significant between traits (p = 0.00). Seekers were significantly different from both the pragmatists and receptives in their behaviors, however pragmatists and receptives did not differ. Discussion and Conclusion: Assessing PSTs may help tailor KT interventions. Since nearly half of clinicians are pragmatists, it may be helpful to target KT interventions to this group, while considering the needs of other styles.

Background: Caregiver relationships are associated with adolescent subjective well-being. Yet, little is known about the contributions of father-adolescent relationship quality to well-being including perseverance, connectedness, and happiness or the specific contributions of father-adolescent relationship quality to these outcomes after accounting for covariates. Objective: This study aimed to understand how father-adolescent relationships and school connectedness interact with one another when positive adolescent functioning are the outcomes. Methods: Adolescents (N = 2,509; M[subscript age] = 15.5; 51.8% male; Black and African American (47.9%), Hispanic (24.8%), and white (17.7%) participating in the FFCWBS provided cross-sectional data. A series of hierarchical regression analyses were conducted to examine direct associations between father-adolescent relationship quality and each of the three adolescent subjective well-being outcomes (perseverance, connectedness, and happiness), and to evaluate the moderating role of adolescent biological sex in these associations. Covariates included race, household income, father's residential status, the adolescent's relationship with the mother and school connectedness. Results: Regressions showed that father-adolescent relationship quality was significantly associated with each well-being outcome beyond the contributions of demographics, mother-adolescent relationships, and school connectedness, and had similar associations with the outcomes by sex. Conclusions: Our conclusions highlight the priority of including and retaining fathers in research and interventions.

Studies from high-income populations have shown that stimulating, supportive communicative input from parents promote children's cognitive and language development. However, fewer studies have identified specific features of input supporting the healthy development of children growing up in low- or middle-income countries. The current study proposes and tests a multi-dimensional framework for understanding whether and how caregiver communicative input mediates the associations between socio-economic conditions and early development. We also examine how caregiver conceptual scaffolding and autonomy support uniquely and synergistically explain variation in child outcomes. Participants were 71 Bangladeshi families with five-year-olds who were exposed to a range of biological and psychosocial hazards from birth. Caregiver-child interactions during snack sharing and semi-structured play were coded for caregiver conceptual scaffolding, autonomy support, and child engagement. Findings indicate that the two dimensions of input were correlated, suggesting that caregivers who provided richer conceptual scaffolds were simultaneously more supportive of children's autonomy. Notably, conceptual scaffolding and autonomy support each mediated associations between maternal education and child verbal intelligence quotient (IQ) scores. Further, caregivers who supported greater autonomy in their children had children who participated in conversations more actively, and these children in turn had higher performance IQ scores. When considered simultaneously, conceptual scaffolding was associated with verbal IQ over and above autonomy support, whereas autonomy support related to child engagement, controlling for conceptual scaffolding. These findings shed new light on how environmental factors may support early development, contributing to the design of family-centered, culturally authentic interventions. A video abstract of this article can be viewed at https://youtu.be/9v_8sIv7ako

This study identified risk, promotive, and protective factors for handgun carriage among 265 primarily African American adolescents (M[subscript age] = 14.3) living in low-income urban areas. Community-based violent victimization and witnessing violence and in-person and cyber forms of peer victimization increased the probability of handgun carriage. Community collective efficacy, including caregiver-reported social connectedness and informal social control, and community developmental strengths/supports, including youth-reported community recognition for prosocial involvement and community developmental assets, moderated relations between both violent victimization and witnessing violence and handgun carriage. School developmental strengths/supports, including school developmental assets and family prosocial involvement in school, moderated relations between in-person and cyber victimization and handgun carriage. Family developmental strengths/supports, including family developmental assets and family recognition and opportunities for prosocial involvement, were associated with lower odds of handgun carriage. Study findings revealed distinct protective factors related to community violence exposure or peer victimization that can inform youth violence prevention efforts.

Youth violence is a national public health concern in USA, especially in resource-constrained urban communities. Between 2018 and 2021, the Healthy Communities for Youth (HCFY) program addressed youth violence prevention in select economically marginalized urban communities, with the HCFY program reducing the likelihood of youth-involved violent crime. Leveraging costs from program expense reports, this study analyzes the costs of the HCFY program in order to inform policymaking and the program's future ongoing implementation. Total HCFY program costs were $821,000 ($290,100 annually including program start-up costs) over the 34-month project period. Operationalization costs contributed the largest share (64.8%), with 45% attributable to intervention coordinators. In the intervention community, the program costs $100 per capita, $1100 per youth-involved crime case, and $8100 per youth-involved violent crime case. Findings were sensitive to the number of youth-involved crime or violent crime cases and costs of high-level program leadership and self-evaluation analysts, with the per youth-involved violent crime case cost ranging between $700 and $1600 over the program period. Analysis of HCFY program costs is an important step in determining the affordability of a community-level program to prevent youth violence in resource-limited urban communities.

The purpose of this scoping review was to synthesize literature regarding audio streaming in the P-12 music classroom by identifying the varied uses, recommendations for equitable access, and gaps in the knowledge base. A total of 23 publications met the criteria for inclusion. Ensemble and general music classrooms in elementary, middle, and high school contexts were represented in the literature with exemplification of concepts, genres, styles, and techniques evident as the most common usage. YouTube, Spotify, and Pandora were frequently referenced as streaming platforms. Authors cited inexpensive or free platforms and ubiquity of access most frequently when referencing equity and streaming. Most authors made no reference to potential access impediments. I identified gaps in the literature, including the uses of streamed music in jazz classrooms, performer compensation, diversity of content, barriers to student access, potential solutions to equitable access issues, and music perception differences for those with limited access.

Light-absorbing aerosols emitted during open biomass burning (BB) events such as wildfires and agricultural burns have a strong impact on the Earth's radiation budget through both direct and indirect effects. Additionally, BB aerosols and gas-phase emissions can substantially reduce air quality at local, regional, and global scales, negatively affecting human health. South America is one of largest contributors to BB emissions globally. After Amazonia, the BB emissions from wildfires and agricultural burns in the grassland plains of northern South America (NSA) are the most significant in the region. However, few studies have analyzed the potential impact of NSA BB emissions on regional air quality. Recent evidence suggests that seasonal variations in air quality in several major cities in NSA could be associated with open biomass burning emissions, but it is still uncertain to what extent those sources impact air quality in the region. In this work, we report on 3 years of continuous equivalent black carbon (eBC) and brown carbon (BrC) observations at a hilltop site located upwind of the city of Bogotá, and we demonstrate its association with fires detected by the MODerate-resolution Imaging Spectroradiometer (MODIS) in a 3000 km × 2000 km domain. Offline PM2.5 filter samples collected during three field campaigns were analyzed to quantify water-soluble organic carbon (WSOC), organic and elemental carbon (OC∕EC), and biomass burning tracers such as levoglucosan, galactosan, and potassium. MODIS active fire data and HYSPLIT back trajectories were used to identify potential biomass burning plumes transported to the city. We analyzed the relationship between BrC, WSOC, water-soluble potassium, and levoglucosan to identify signals of the regional transport of BB aerosols. Our results confirm that regional biomass burning transport from wildfires occurs annually during the months of January and April. The seasonality of eBC closely followed that of PM2.5 at the city air quality stations; however, the observed seasonality of BrC is distinctly different to that of eBC and strongly associated with regional fire counts. The strong correlation between BrC and regional fire counts was observed at daily, weekly, and monthly timescales. WSOC at the measurement site was observed to increase linearly with levoglucosan during high BB periods and to remain constant at ∼2.5 µgC m−3 during the low BB seasons. Our findings show, for the first time in this region, that aged BB plumes can regularly reach densely populated areas in the Central Andes of northern South America. A source footprint analysis involving BrC observations, back trajectories, and remotely sensed fire activity shows that the eastern savannas in NSA are the main BB source region for the domain analyzed.

Although the value of physical activity for physical and mental health is well accepted, benefits for learning are less clear. Research about the incorporation of physical activity in teaching practice and the benefits teachers perceive for student learning and behaviour is sparse. In the current study, Australian teachers (n = 222) completed an online survey. Over 70% of the participants reported using physical activity in their teaching practice. Activities included movement breaks, such as stretches and balancing games, or ones that were intended to stimulate the brain, described as 'crossing the midline' exercises. Some teachers integrated physical activity with academic content, such as tossing a ball while practising math facts. Among the perceived benefits of physical activity were energising students and promoting their engagement with learning. Overall, there was strong acceptance of the value of incorporating physical activity in teaching practice.

The 2014 Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ) aimed to better characterize summertime air quality in the Northern Front Range Metropolitan Area (NFRMA) and its impact on surrounding areas. As part of this study, measurements of gas- and particle-phase species were collected in Rocky Mountain National Park (ROMO), located in the mountains west of the urban northern Front Range corridor from July to October 2014. We report on measurements of ozone from two locations in the park and a suite of volatile organic compounds (VOCs) measured using a continuous real-time gas chromatography (GC) system and a quadrupole proton-transfer-reaction mass spectrometer (PRT-MS) at the ROMO Longs Peak (ROMO-LP) air quality site. We also measured VOCs using canister samples collected along transects connecting the NFRMA and ROMO. These datasets show that ROMO is impacted by NFRMA emission sources, and high observed mixing ratios of VOCs associated with oil and gas extraction (e.g. ethane) and urban sources (e.g. ethene and C2Cl4) occur during periods of upslope transport. Hourly ozone mixing ratios exceeded 70 ppb during six events. Two of the six events were largely associated with VOCs from the oil and gas sector, three high ozone events were associated with a mixture of VOCs from urban and oil and gas sources, and one high ozone event was driven by a stratospheric intrusion. For the high ozone events most associated with emissions from oil and gas activities, we estimate that VOCs and NOx from sources along the Front Range contributed ∼20 ppbv of additional ozone.