A better representation of VOC chemistry in WRF-Chem and its impact on ozone over Los Angeles.

The declining trend in vehicle emissions has underscored the growing significance of Volatile Organic Compound (VOC) emissions from Volatile Chemical Products (VCP). However, accurately representing VOC chemistry in simplified chemical mechanisms remains challenging due to its chemical complexity including speciation and reactivity. Previous studies have predominantly focused on VOCs from fossil fuel sources, leading to an underrepresentation of VOC chemistry from VCP sources. We developed an integrated chemical mechanism, RACM2B-VCP, that is compatible with WRF-Chem and is aimed to enhance the representation of VOC chemistry, particularly from VCP sources, within the present urban environment. Evaluation against the Air Quality System (AQS) network data demonstrates that our model configured with RACM2B-VCP reproduces both the magnitude and spatial variability of O3 as well as PM2.5 in Los Angeles. Furthermore, evaluation against comprehensive measurements of O3 and PM2.5 precursors from the Reevaluating the Chemistry of Air Pollutants in California (RECAP-CA) airborne campaign and the Southwest Urban NO x and VOC Experiment (SUNVEx) ground site and mobile laboratory campaign, confirm the model's accuracy in representing NOx and many VOCs and highlight remaining biases. Although there exists an underprediction in the total VOC reactivity of observed VOC species, our model with RACM2B-VCP exhibits good agreement for VOC markers emitted from different sectors, including biogenic, fossil fuel, and VCP sources. Through sensitivity analyses, we probe the contributions of VCP and fossil fuel emissions to total VOC reactivity and O3. Our results reveal that 52% of the VOC reactivity and 35% of the local enhancement of MDA8 O3 arise from anthropogenic VOC emissions in Los Angeles. Significantly, over 50% of this anthropogenic fraction of either VOC reactivity or O3 is attributed to VCP emissions. The RACM2B-VCP mechanism created, described, and evaluated in this work is ideally suited for accurately representing ozone for the right reasons in the present urban environment where mobile, biogenic, and VCP VOCs are all important contributors to ozone formation.

Influence of Wildfire on Urban Ozone: An Observationally Constrained Box Modeling Study at a Site in the Colorado Front Range.

Increasing trends in biomass burning emissions significantly impact air quality in North America. Enhanced mixing ratios of ozone (O3) in urban areas during smoke-impacted periods occur through transport of O3 produced within the smoke or through mixing of pyrogenic volatile organic compounds (PVOCs) with urban nitrogen oxides (NOx = NO + NO2) to enhance local O3 production. Here, we analyze a set of detailed chemical measurements, including carbon monoxide (CO), NOx, and speciated volatile organic compounds (VOCs), to evaluate the effects of smoke transported from relatively local and long-range fires on O3 measured at a site in Boulder, Colorado, during summer 2020. Relative to the smoke-free period, CO, background O3, OH reactivity, and total VOCs increased during both the local and long-range smoke periods, but NOx mixing ratios remained approximately constant. These observations are consistent with transport of PVOCs (comprised primarily of oxygenates) but not NOx with the smoke and with the influence of O3 produced within the smoke upwind of the urban area. Box-model calculations show that local O3 production during all three periods was in the NOx-sensitive regime. Consequently, this locally produced O3 was similar in all three periods and was relatively insensitive to the increase in PVOCs. However, calculated NOx sensitivities show that PVOCs substantially increase O3 production in the transition and NOx-saturated (VOC-sensitive) regimes. These results suggest that (1) O3 produced during smoke transport is the main driver for O3 increases in NOx-sensitive urban areas and (2) smoke may cause an additional increase in local O3 production in NOx-saturated (VOC-sensitive) urban areas. Additional detailed VOC and NOx measurements in smoke impacted urban areas are necessary to broadly quantify the effects of wildfire smoke on urban O3 and develop effective mitigation strategies.

An Assessment of Program Eligibility Among Participants in Day Reporting Centers.

Day reporting centers (DRCs) vary considerably in how participant eligibility is determined and to date, there is little to no knowledge whether criteria for DRC eligibly are appropriately applied in program entrance. This study examines a statewide sample of individuals in community supervision settings and compares DRC eligibility criteria between DRC and non-DRC participants to examine differences between DRC participants and non-participants. Using a propensity score matched sample of 1,554 participants, study findings suggest that DRC participants show higher risk, need, and responsivity factors, consistent with the DRC programing model. These results suggest many individuals appear to be appropriately matched to DRCs, which may in turn, may influence their likelihood of program success, among other factors.

African Americans, Caribbean Blacks and Depression: Which Biopsychosocial Factors Should Social Workers Focus On? Results from the National Survey of American Life (NSAL).

Research suggests that African Americans may be more likely to experience depression, especially severe depression, than other racial or ethnic groups in the United States. Overall there is scant research comparing the relationship between ethnicity and depression among the U.S. Black population. The purpose of this study is to identify the most significant biopsychosocial factors social workers can address in the prevention and treatment of depression in African American and first generations Caribbean Black clients. Data was from the National Survey of American Life (NSAL). Bivariate associations showed that respondents who reported higher self-esteem, lower hopelessness, higher sense of mastery, and lower discrimination showed lower likelihood of having Major Depressive Disorder (MDD). The logistic regression model suggested that respondents who have ever had a chronic disease were more likely to report depression than those who have not ever had a chronic disease. Caribbean Blacks were more likely to report depression compared to African Americans. Additionally, respondents who reported higher discrimination scores were more likely to report depression. This study suggests that social workers should embrace the interconnectedness and holistic approach of the biopsychosocial model in their case conceptualizations, prevention strategies, and treatment modalities.

Ozone chemistry in western U.S. wildfire plumes.

Wildfires are a substantial but poorly quantified source of tropospheric ozone (O3). Here, to investigate the highly variable O3 chemistry in wildfire plumes, we exploit the in situ chemical characterization of western wildfires during the FIREX-AQ flight campaign and show that O3 production can be predicted as a function of experimentally constrained OH exposure, volatile organic compound (VOC) reactivity, and the fate of peroxy radicals. The O3 chemistry exhibits rapid transition in chemical regimes. Within a few daylight hours, the O3 formation substantially slows and is largely limited by the abundance of nitrogen oxides (NOx). This finding supports previous observations that O3 formation is enhanced when VOC-rich wildfire smoke mixes into NOx-rich urban plumes, thereby deteriorating urban air quality. Last, we relate O3 chemistry to the underlying fire characteristics, enabling a more accurate representation of wildfire chemistry in atmospheric models that are used to study air quality and predict climate.

Novel Analysis to Quantify Plume Crosswind Heterogeneity Applied to Biomass Burning Smoke.

We present a novel method, the Gaussian observational model for edge to center heterogeneity (GOMECH), to quantify the horizontal chemical structure of plumes. GOMECH fits observations of short-lived emissions or products against a long-lived tracer (e.g., CO) to provide relative metrics for the plume width (wi/wCO) and center (bi/wCO). To validate GOMECH, we investigate OH and NO3 oxidation processes in smoke plumes sampled during FIREX-AQ (Fire Influence on Regional to Global Environments and Air Quality, a 2019 wildfire smoke study). An analysis of 430 crosswind transects demonstrates that nitrous acid (HONO), a primary source of OH, is narrower than CO (wHONO/wCO = 0.73-0.84 ± 0.01) and maleic anhydride (an OH oxidation product) is enhanced on plume edges (wmaleicanhydride/wCO = 1.06-1.12 ± 0.01). By contrast, NO3 production [P(NO3)] occurs mainly at the plume center (wP(NO3)/wCO = 0.91-1.00 ± 0.01). Phenolic emissions, highly reactive to OH and NO3, are narrower than CO (wphenol/wCO = 0.96 ± 0.03, wcatechol/wCO = 0.91 ± 0.01, and wmethylcatechol/wCO = 0.84 ± 0.01), suggesting that plume edge phenolic losses are the greatest. Yet, nitrophenolic aerosol, their oxidation product, is the greatest at the plume center (wnitrophenolicaerosol/wCO = 0.95 ± 0.02). In a large plume case study, GOMECH suggests that nitrocatechol aerosol is most associated with P(NO3). Last, we corroborate GOMECH with a large eddy simulation model which suggests most (55%) of nitrocatechol is produced through NO3 in our case study.

Variability and Time of Day Dependence of Ozone Photochemistry in Western Wildfire Plumes.

Understanding the efficiency and variability of photochemical ozone (O3) production from western wildfire plumes is important to accurately estimate their influence on North American air quality. A set of photochemical measurements were made from the NOAA Twin Otter research aircraft as a part of the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) experiment. We use a zero-dimensional (0-D) box model to investigate the chemistry driving O3 production in modeled plumes. Modeled afternoon plumes reached a maximum O3 mixing ratio of 140 ± 50 ppbv (average ± standard deviation) within 20 ± 10 min of emission compared to 76 ± 12 ppbv in 60 ± 30 min in evening plumes. Afternoon and evening maximum O3 isopleths indicate that plumes were near their peak in NOx efficiency. A radical budget describes the NOx volatile - organic compound (VOC) sensitivities of these plumes. Afternoon plumes displayed a rapid transition from VOC-sensitive to NOx-sensitive chemistry, driven by HOx (=OH + HO2) production from photolysis of nitrous acid (HONO) (48 ± 20% of primary HOx) and formaldehyde (HCHO) (26 ± 9%) emitted directly from the fire. Evening plumes exhibit a slower transition from peak NOx efficiency to VOC-sensitive O3 production caused by a reduction in photolysis rates and fire emissions. HOx production in evening plumes is controlled by HONO photolysis (53 ± 7%), HCHO photolysis (18 ± 9%), and alkene ozonolysis (17 ± 9%).

Observations Confirm that Volatile Chemical Products Are a Major Source of Petrochemical Emissions in U.S. Cities.

Despite decades of declining air pollution, urban U.S. areas are still affected by summertime ozone and wintertime particulate matter exceedance events. Volatile organic compounds (VOCs) are known precursors of secondary organic aerosol (SOA) and photochemically produced ozone. Urban VOC emission sources, including on-road transportation emissions, have decreased significantly over the past few decades through successful regulatory measures. These drastic reductions in VOC emissions have led to a change in the distribution of urban emissions and noncombustion sources of VOCs such as those from volatile chemical products (VCPs), which now account for a higher fraction of the urban VOC burden. Given this shift in emission sources, it is essential to quantify the relative contribution of VCP and mobile source emissions to urban pollution. Herein, ground site and mobile laboratory measurements of VOCs were performed. Two ground site locations with different population densities, Boulder, CO, and New York City (NYC), NY, were chosen in order to evaluate the influence of VCPs in cities with varying mixtures of VCPs and mobile source emissions. Positive matrix factorization was used to attribute hundreds of compounds to mobile- and VCP-dominated sources. VCP-dominated emissions contributed to 42 and 78% of anthropogenic VOC emissions for Boulder and NYC, respectively, while mobile source emissions contributed 58 and 22%. Apportioned VOC emissions were compared to those estimated from the Fuel-based Inventory of Vehicle Emissions and VCPs and agreed to within 25% for the bulk comparison and within 30% for more than half of individual compounds. The evaluated inventory was extended to other U.S. cities and it suggests that 50 to 80% of emissions, reactivity, and the SOA-forming potential of urban anthropogenic VOCs are associated with VCP-dominated sources, demonstrating their important role in urban U.S. air quality.

The Effects of Hopelessness on Chronic Disease Among African Americans and Caribbean Blacks: Findings from the National Survey of American Life (NSAL).

This paper examines the relationship between hopelessness on chronic disease in a national sample of African Americans (3570) and Caribbean Blacks (1438) Using the National Survey of American Life. A multivariate negative binomial regression examined whether chronic disease is associated with hopelessness, controlling for sociodemographic characteristics. Overall, 13.14% of the sample reported they were highly hopeless, and 31.5% indicated they were moderately hopeless. About 19% of respondents experienced chronic disease. Bivariate associations showed that those who have ever had chronic disease significantly differed from those who did not in regard to age, gender and spirituality. Multivariate results showed that respondents who ever have had chronic disease reported significantly higher hopelessness scores than those with no chronic disease. The study findings contribute to the current body of literature by supporting findings from smaller studies on the relationship between depression and hopelessness in African Americans and Caribbean Blacks.

Black Male Mental Health and the Black Church: Advancing a Collaborative Partnership and Research Agenda.

This article explores the role the Black Church could play in facilitating spiritually sensitive, culturally relevant and gender-specific services to address the mental health and well-being of Black males. The help-seeking behaviors of Black men are examined as the authors offer two theories: the body, mind, spirit, environment, social, transcendent, and health, illness, men, and masculinities that may assist the Black Church in functioning as an effective support networks for healthy Black male mental health. Next, the authors discuss implications for practice, research, and education, and lastly, eight recommendations for Black Church leadership, social workers, and mental health professionals are also discussed.

Correction to: The Impact of Religiosity on Substance Abuse and Obesity in African Americans.

The original version of this article unfortunately contained a mistake in the author names. The co-author names should be David Meetze and Ronald Whicker Jr. instead of David Meetz and Ronald Wicker. The original article has been corrected.

The Impact of Religiosity on Substance Abuse and Obesity in African Americans.

Among the African American community, there exist many health disparities which warrant greater examination through the practice of social work. The aim of the present research was to explore the impact of religiosity on substance abuse and obesity among African American populations by employing a systematic review of the current body of literature on this subject. While many of the studies reviewed found at least a weak relationship between religiosity and obesity, such results were not consistent across all materials examined. Among those studies that found a correlation between these factors, many demonstrated that religiosity had a positive impact on substance abuse and obesity. A discussion of the implications of these findings is submitted as a means of illuminating the significance of all research findings that were examined. Limitations such as more standardized criteria for inclusion of research material are identified and discussed. Implications for future research are presented to promote the advancement of future efforts in this area research.

"Moving Toward Healthy": Insights Into Food Choices of Mothers in Residential Recovery.

This study utilized participatory and potentially empowering qualitative research methods of photo-elicitation and face-to-face interviews to investigate food choices of mothers living with their children in a residential substance use disorder recovery program. Face-to-face interviews were conducted with nine women (25-40 years) living in a residential substance use disorder recovery program in the Southeastern United States. Each audio recorded and transcribed interview was coded individually before collectively developing a consensual version of the codebook and identifying themes. The recovering women in this study expressed a new or renewed desire to "eat healthy" and voiced concerns about the nutritional value of foods. Food choices were influenced by their children's nutritional needs and food preferences, their own food preferences and habits, the financial resources available to them, their personal food preparation self-efficacy and skills, and the limitations inherent in residential recovery. Understanding food choices benefits both recovering parents and their children.

Lipid analysis of eight human breast cancer cell lines with ToF-SIMS.

In this work, four triple negative (TN) cell lines, three ER+ and PR+ receptor positive (RP) cell lines, and one ER+, PR+, and HER2+ cell line were chemically distinguished from one another using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and principal component analysis (PCA). PCA scores separation was observed between the individual cell lines within a given classification (TN and RP) and there were distinctly different trends found in the fatty acid and lipid compositions of the two different classifications. These trends indicated that the RP cell lines separated out based on the carbon chain length of the lipids while the TN cell lines showed separation based on cholesterol-related peaks (in the positive ion data). Both cell types separated out by trends in fatty acid chain length and saturation in the negative ions. These chemical differences may be manifestations of unique metabolic processes within each of the different cell lines. Additionally, the HER2+ cell line was distinguished from three other RP cell types as having a unique distribution of fatty acids including anticorrelation to 18-carbon chain fatty acids. As these cell lines could not be grown in the same growth media, a combination of chemical fixation, rinsing, C60 (+) presputtering, and selection of cellular regions-of-interest is also presented as a successful method to acquire ToF-SIMS data from cell lines grown in different media.

The effects of emission control strategies on light-absorbing carbon emissions from a modern heavy-duty diesel engine.

UNLABELLED: Control of atmospheric black carbon (BC) and brown carbon (BrC) has been proposed as an important pathway to climate change mitigation, but sources of BC and BrC are still not well understood. In order to better identify the role of modern heavy-duty diesel engines on the production of BC and BrC, emissions from a heavy-duty diesel engine operating with different emission control strategies were examined using a source dilution sampling system. The effect of a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) on light-absorbing carbon (LAC) was evaluated at three steady-state engine operation modes: idle, 50% speed and load, and 100% speed and load. LAC was measured with four different engine configurations: engine out, DOC out, DPF out, and engine out with an altered combustion calibration. BC and BrC emission rates were measured with the Aethalometer (AE-31). EC and BC emission rates normalized to the mass of CO2emitted increased with increasing engine speed and load. Emission rates normalized to brake-specific work did not exhibit similar trends with speed and load, but rather the highest emission rate was measured at idle. EC and OC emissions were reduced by 99% when the DOC and DPF architecture was applied. The application of a DPF was equally effective at removing 99% of the BC fraction of PM, proving to be an important control strategy for both LAC and PM. BC emissions were unexpectedly increased across the DOC, seemingly due to a change aerosol optical properties. Removal of exhaust gas recirculation (EGR) flow due to simulated EGR cooler failure caused a large increase in OC and BrC emission rates at idle, but had limited influence during high load operation. LAC emissions proved to be sensitive to the same control strategies effective at controlling the total mass of diesel PM. IMPLICATIONS: In the context of black carbon emissions, very small emission rates of brown carbon were measured over a range of control technologies and engine operating conditions. During specific idle engine operation without EGR and adjusted fueling conditions, brown carbon can be formed in significant amounts, requiring careful management tactics. Control technologies for particulate matter are very effective for light-absorbing carbon, reducing black carbon emissions to near zero for modern engines equipped with a DPF. Efforts to control atmospheric brown carbon need to focus on other sources other than modern diesel engines, such as biomass burning.

TOF-SIMS 3D imaging of native and non-native species within HeLa cells.

In this study, a non-native chemical species, bromodeoxyuridine (BrdU), was imaged within single HeLa cells using time-of-flight secondary ion mass spectrometry (TOF-SIMS). z-corrected 3D images were reconstructed that accurately portray the distribution of intracellular BrdU as well as other intracellular structures. The BrdU was localized to the nucleus of cells, whereas structures composed of CxHyOz(-) species were located in bundles on the periphery of cells. The CxHyOz(-) subcellular features had a spatial resolution at or slightly below a micrometer (900 nm), as defined by the distance between the 16% and 84% intensities in a line scan across the edge of the features. Additionally, important parameters influencing the quality of the HeLa cell 3D images were investigated. Atomic force microscopy measurements revealed that the HeLa cells were sputtered at a rate of approximately 4 nm per 10(13) C60(+) ions/cm(2) at 10 keV and a 45° incident angle. Optimal 3D images were acquired using a Bi3(+) liquid metal ion gun operating in the simultaneous high mass and spatial resolution mode.

Factors leading African Americans and black Caribbeans to use social work services for treating mental and substance use disorders.

This secondary analysis of 5,000 African Americans and black Caribbeans explored how their use of social work services to address mental and substance use disorders was associated with the disorder involved as well as their perceived need for services, belief system, family resources, proximity to services, social-structural factors, and demographic characteristics. The sample was extracted from a national data set. Results of multinomial logistic regression showed that use of social work services was increased by dual diagnosis, substance use disorder alone, and mental disorder alone; by deteriorating mental health; by perceived stigma in treatment use; by welfare receipt and insurance coverage for mental health services; and by college graduation. Results also showed that use of services outside social work was promoted by dual diagnosis, substance use disorder alone, and mental disorder alone; by deteriorating mental health; by experience of racial discrimination; by insurance coverage for mental health services; by college education or graduation; and by female gender and increasing age. The findings' implications for social work intervention and education are discussed.