HDAC3 ensures stepwise epidermal stratification via NCoR/SMRT-reliant mechanisms independent of its histone deacetylase activity.

Chromatin modifiers play critical roles in epidermal development, but the functions of histone deacetylases in this context are poorly understood. The class I HDAC, HDAC3, is of particular interest because it plays divergent roles in different tissues by partnering with tissue-specific transcription factors. We found that HDAC3 is expressed broadly in embryonic epidermis and is required for its orderly stepwise stratification. HDAC3 protein stability in vivo relies on NCoR and SMRT, which function redundantly in epidermal development. However, point mutations in the NCoR and SMRT deacetylase-activating domains, which are required for HDAC3's enzymatic function, permit normal stratification, indicating that HDAC3's roles in this context are largely independent of its histone deacetylase activity. HDAC3-bound sites are significantly enriched for predicted binding motifs for critical epidermal transcription factors including AP1, GRHL, and KLF family members. Our results suggest that among these, HDAC3 operates in conjunction with KLF4 to repress inappropriate expression of Tgm1, Krt16, and Aqp3 In parallel, HDAC3 suppresses expression of inflammatory cytokines through a Rela-dependent mechanism. These data identify HDAC3 as a hub coordinating multiple aspects of epidermal barrier acquisition.

Estimate of OH trends over one decade in North American cities.

The hydroxyl radical (OH) is the most important oxidant on global and local scales in the troposphere. Urban OH controls the removal rate of primary pollutants and triggers the production of ozone. Interannual trends of OH in urban areas are not well documented or understood due to the short lifetime and high spatial heterogeneity of OH. We utilize machine learning with observational inputs emphasizing satellite remote sensing observations to predict surface OH in 49 North American cities from 2005 to 2014. We observe changes in the summertime OH over one decade, with wide variation among different cities. In 2014, compared to the summertime OH in 2005, 3 cities show a significant increase of OH, whereas, in 27 cities, OH decreases in 2014. The year-to-year variation of OH is mapped to the decline of the NO2 column. We conclude that these cities in this analysis are either in the NOx-limited regime or at the transition from a NOx suppressed regime to a NOx-limited regime. The result emphasizes that, in the future, controlling NOx emissions will be most effective in regulating the ozone pollution in these cities.

Balanced control of thermogenesis by nuclear receptor corepressors in brown adipose tissue.

Brown adipose tissue (BAT) is a key thermogenic organ whose expression of uncoupling protein 1 (UCP1) and ability to maintain body temperature in response to acute cold exposure require histone deacetylase 3 (HDAC3). HDAC3 exists in tight association with nuclear receptor corepressors (NCoRs) NCoR1 and NCoR2 (also known as silencing mediator of retinoid and thyroid receptors [SMRT]), but the functions of NCoR1/2 in BAT have not been established. Here we report that as expected, genetic loss of NCoR1/2 in BAT (NCoR1/2 BAT-dKO) leads to loss of HDAC3 activity. In addition, HDAC3 is no longer bound at its physiological genomic sites in the absence of NCoR1/2, leading to a shared deregulation of BAT lipid metabolism between NCoR1/2 BAT-dKO and HDAC3 BAT-KO mice. Despite these commonalities, loss of NCoR1/2 in BAT does not phenocopy the cold sensitivity observed in HDAC3 BAT-KO, nor does loss of either corepressor alone. Instead, BAT lacking NCoR1/2 is inflamed, particularly with respect to the interleukin-17 axis that increases thermogenic capacity by enhancing innervation. Integration of BAT RNA sequencing and chromatin immunoprecipitation sequencing data revealed that NCoR1/2 directly regulate Mmp9, which integrates extracellular matrix remodeling and inflammation. These findings reveal pleiotropic functions of the NCoR/HDAC3 corepressor complex in BAT, such that HDAC3-independent suppression of BAT inflammation counterbalances stimulation of HDAC3 activity in the control of thermogenesis.

Measurements of Atmosphere-Biosphere Exchange of Oxidized Nitrogen and Implications for the Chemistry of Atmospheric NOx.

ConspectusThe atmosphere-biosphere exchange of nitrogen oxides plays a key role in determining the composition of reactive nitrogen in terrestrial vegetated environments. The emission of nitric oxide (NO) from soils is an important atmospheric source of reactive nitrogen. NO is rapidly interconverted with NO2, making up the chemical family NOx (NOx ≡ NO2 + NO). NOx further reacts with the oxidation products of volatile organic compounds (VOCs) to form the functionalized nitrogen oxide groups acyl peroxynitrates (APNs = R(O)O2NO2) and alkyl nitrates (ANs = RONO2). Both canopy-level field measurements and laboratory studies suggest that the absorption of nitrogen dioxide NO2 and APNs by vegetation is a significant sink of atmospheric NOx, removing a large fraction of global soil-emitted NOx and providing key control on the amounts and lifetimes of NOx and reactive nitrogen in the atmosphere. Nitrogen oxides influence the production of surface O3 and secondary aerosols. The balance of the emission and uptake of nitrogen oxides thus provides a mechanism for the regulation of regional air quality. The biosphere, via this biogeochemical cycling of nitrogen oxides, is becoming an increasingly important determining factor for airborne pollutants as much of the world continues to reduce the amount of combustion-related nitrogen oxide emissions. Understanding the function of the biosphere as a source and sink of reactive nitrogen is therefore ever more critical in evaluating the effects of future and current emissions of nitrogen oxides on human and ecosystem health.Laboratory measurements of the foliar deposition of NO2 and other reactive nitrogen species suggest that there is a substantial diversity of uptake rates under varying environmental conditions and for different species of vegetation that is not currently reflected in the widely utilized chemical transport models. Our branch chamber measurements on a wide variety of North American tree species highlight the variability in the rates of both photosynthesis and nitrogen oxide deposition among several different nitrogen oxide compounds. Box-modeling and satellite measurement approaches demonstrate how disparities between our understanding of nitrogen oxide foliar exchange in the laboratory and what is represented in models can lead to misrepresentations of the net ecosystem exchange of nitrogen. This has important implications for assumptions of in-canopy chemistry, soil emissions of NO, canopy reductions of NOx, lifetimes of trace gases, and the impact of the biosphere on air quality.

The association of depression and anxiety symptoms to three different types of activities of daily living in persons with and without HIV.

Mood disorders are highly prevalent in people living with HIV (PLWH) and represent a potential contributor to functional impairment in activities of daily living. We aimed to determine if (1) Anxiety and depression symptoms were independently associated with impairments in basic self-care, role functioning, and social functioning and (2) PLWH differentially experienced impairments due to mood symptoms compared to those without HIV. Data for this study were obtained from 150 individuals (87 PLWH, 61% male, mean age = 44) via a cross-sectional study on alcohol and HIV-associated brain dysfunction. The Beck Anxiety Inventory (BAI) and the Center for Epidemiologic Studies Depression Scale (CES-D) were used to assess anxiety and depressive symptoms. Higher anxiety symptoms were associated with role functioning impairment, while higher depressive and anxiety symptoms were each associated with social functioning impairment. As depressive symptoms increased, PLWH were 3x more likely to have impairments in role functioning compared to those without HIV. HIV status did not interact with mood symptoms to affect basic self-care or social functioning. Overall, mood symptoms are associated with different types of functional impairment, and improved management of mood symptoms could lead to improved role and social functioning.

Sustained Reductions of Bay Area CO2 Emissions 2018-2022.

Cities represent a significant and growing portion of global carbon dioxide (CO2) emissions. Quantifying urban emissions and trends over time is needed to evaluate the efficacy of policy targeting emission reductions as well as to understand more fundamental questions about the urban biosphere. A number of approaches have been proposed to measure, report, and verify (MRV) changes in urban CO2 emissions. Here we show that a modest capital cost, spatially dense network of sensors, the Berkeley Environmental Air Quality and CO2 Network (BEACO2N), in combination with Bayesian inversions, result in a synthesis of measured CO2 concentrations and meteorology to yield an improved estimate of CO2 emissions and provide a cost-effective and accurate assessment of CO2 emissions trends over time. We describe nearly 5 years of continuous CO2 observations (2018-2022) in a midsized urban region (the San Francisco Bay Area). These observed concentrations constrain a Bayesian inversion that indicates the interannual trend in urban CO2 emissions in the region has been a modest decrease at a rate of 1.8 ± 0.3%/year. We interpret this decrease as primarily due to passenger vehicle electrification, reducing on-road emissions at a rate of 2.6 ± 0.7%/year.

Change in medial frontal cerebral metabolite concentrations following bariatric surgery.

Obesity is associated with adverse effects on brain health, including an increased risk of neurodegenerative diseases. Changes in cerebral metabolism may underlie or precede structural and functional brain changes. While bariatric surgery is known to be effective in inducing weight loss and improving obesity-related medical comorbidities, few studies have examined whether it may be able to improve brain metabolism. In the present study, we examined changes in cerebral metabolite concentrations in participants with obesity who underwent bariatric surgery. Thirty-five patients with obesity (body mass index ≥ 35 kg/m2 ) were recruited from a bariatric surgery candidate nutrition class. They completed single voxel proton magnetic resonance spectroscopy at baseline (presurgery) and within 1 year postsurgery. Spectra were obtained from a large medial frontal brain region using a PRESS sequence on a 3-T Siemens Verio scanner. The acquisition parameters were TR = 3000 ms and TE = 37 ms. Tissue-corrected metabolite concentrations were determined using Osprey. Paired t-tests were used to examine within-subject change in metabolite concentrations, and correlations were used to relate these changes to other health-related outcomes, including weight loss and glycated hemoglobin (HbA1c ), a measure of blood sugar levels. Bariatric surgery was associated with a reduction in cerebral choline-containing compounds (Cho; t [34] = - 3.79, p < 0.001, d = -0.64) and myo-inositol (mI; t [34] = - 2.81, p < 0.01, d = -0.47) concentrations. There were no significant changes in N-acetyl-aspartate, creatine, or glutamate and glutamine concentrations. Reductions in Cho were associated with greater weight loss (r = 0.40, p < 0.05), and reductions in mI were associated with greater reductions in HbA1c (r = 0.44, p < 0.05). In conclusion, participants who underwent bariatric surgery exhibited reductions in cerebral Cho and mI concentrations, which were associated with improvements in weight loss and glycemic control. Given that elevated levels of Cho and mI have been implicated in neuroinflammation, reduction in these metabolites after bariatric surgery may reflect amelioration of obesity-related neuroinflammatory processes. As such, our results provide evidence that bariatric surgery may improve brain health and metabolism in individuals with obesity.

Space-Based Observations of Ozone Precursors within California Wildfire Plumes and the Impacts on Ozone-NOx-VOC Chemistry.

The frequency of wildfires in the western United States has escalated in recent decades. Here we examine the impacts of wildfires on ground-level ozone (O3) precursors and the O3-NOx-VOC chemistry from the source to downwind urban areas. We use satellite retrievals of nitrogen dioxide (NO2) and formaldehyde (HCHO, an indicator of VOC) from the Tropospheric Monitoring Instrument (TROPOMI) to track the evolution of O3 precursors from wildfires over California from 2018 to 2020. We improved these satellite retrievals by updating the a priori profiles and explicitly accounting for the effects of smoke aerosols. TROPOMI observations reveal that the extensive and intense fire smoke in 2020 led to an overall increase in statewide annual average HCHO and NO2 columns by 16% and 9%. The increase in the level of NO2 offsets the anthropogenic NOx emission reduction from the COVID-19 lockdown. The enhancement of NO2 within fire plumes is concentrated near the regions actively burning, whereas the enhancement of HCHO is far-reaching, extending from the source regions to urban areas downwind due to the secondary production of HCHO from longer-lived VOCs such as ethene. Consequently, a larger increase in NOx occurs in NOx-limited source regions, while a greater increase in HCHO occurs in VOC-limited urban areas, both contributing to more efficient O3 production.

Comparison between Spatially Resolved Airborne Flux Measurements and Emission Inventories of Volatile Organic Compounds in Los Angeles.

Los Angeles is a major hotspot for ozone and particulate matter air pollution in the United States. Ozone and PM2.5 in this region have not improved substantially for the past decade, despite a reduction in vehicular emissions of their precursors, NOx and volatile organic compounds (VOCs). This reduction in "traditional" sources has made the current emission mixture of air pollutant precursors more uncertain. To map and quantify emissions of a wide range of VOCs in this urban area, we performed airborne eddy covariance measurements with wavelet analysis. VOC fluxes measured include tracers for source categories, such as traffic, vegetation, and volatile chemical products (VCPs). Mass fluxes were dominated by oxygenated VOCs, with ethanol contributing ∼29% of the total. In terms of OH reactivity and aerosol formation potential, terpenoids contributed more than half. Observed fluxes were compared with two commonly used emission inventories: the California Air Resources Board inventory and the combination of the Biogenic Emission Inventory System with the Fuel-based Inventory of Vehicle Emissions combined with Volatile Chemical Products (FIVE-VCP). The comparison shows mismatches regarding the amount, spatial distribution, and weekend effects of observed VOC emissions with the inventories. The agreement was best for typical transportation related VOCs, while discrepancies were larger for biogenic and VCP-related VOCs.

Methane Emissions from Dairy Operations in California's San Joaquin Valley Evaluated Using Airborne Flux Measurements.

State inventories indicate that dairy operations account for nearly half of California's methane budget. Recent analyses suggest, however, that these emissions may be underestimated, complicating efforts to develop emission reduction strategies. Here, we report estimates of dairy methane emissions in the southern San Joaquin Valley (SJV) of California in June 2021 using airborne flux measurements. We find average dairy methane fluxes of 512 ± 178 mg m-2 h-1 from a region of 300+ dairies near Visalia, CA using a combination of eddy covariance and mass balance-based techniques, corresponding to 118 ± 41 kg dairy-1 h-1. These values estimated during our June campaign are 39 ± 48% larger than annual average estimates from the recently developed VISTA-CA inventory. We observed notable increases in emissions with temperature. Our estimates align well with inventory predictions when parametrizations for the temperature dependence of emissions are applied. Our measurements further demonstrate that the VISTA-CA emission inventory is considerably more accurate than the EPA GHG-I inventory in this region. Source apportionment analyses confirm that dairy operations produce the majority of methane emissions in the southern SJV (∼65%). Fugitive oil and gas (O&G) sources account for the remaining ∼35%. Our results support the accuracy of the process-based models used to develop dairy emission inventories and highlight the need for additional investigation of the meteorological dependence of these emissions.

Improved Spatial Resolution in Modeling of Nitrogen Oxide Concentrations in the Los Angeles Basin.

The extent to which emission control technologies and policies have reduced anthropogenic NOx emissions from motor vehicles is large but uncertain. We evaluate a fuel-based emission inventory for southern California during the June 2021 period, coinciding with the Re-Evaluating the Chemistry of Air Pollutants in CAlifornia (RECAP-CA) field campaign. A modified version of the Fuel-based Inventory of Vehicle Emissions (FIVE) is presented, incorporating 1.3 km resolution gridding and a new light-/medium-duty diesel vehicle category. NOx concentrations and weekday-weekend differences were predicted using the WRF-Chem model and evaluated using satellite and aircraft observations. Model performance was similar on weekdays and weekends, indicating appropriate day-of-week scaling of NOx emissions and a reasonable distribution of emissions by sector. Large observed weekend decreases in NOx are mainly due to changes in on-road vehicle emissions. The inventory presented in this study suggests that on-road vehicles were responsible for 55-72% of the NOx emissions in the South Coast Air Basin, compared to the corresponding fraction (43%) in the planning inventory from the South Coast Air Quality Management District. This fuel-based inventory suggests on-road NOx emissions that are 1.5 ± 0.4, 2.8 ± 0.6, and 1.3 ± 0.7 times the reference EMFAC model estimates for on-road gasoline, light- and medium-duty diesel, and heavy-duty diesel, respectively.

Functional Neural Correlates of a Useful Field of View (UFOV)-Based fMRI Task in Older Adults.

Declines in processing speed performance occur in aging and are a critical marker of functional independence in older adults. Studies suggest that Useful Field of View (UFOV) training may ameliorate cognitive decline. Despite its efficacy, little is known about the neural correlates of this task. Within the current study, 233 healthy older adults completed a UFOV-based task while undergoing functional magnetic resonance imaging (fMRI). During the "stimulus" portion of this task, participants must identify a target in the center of the screen and the location of a target in the periphery, among distractors. During the "probe" portion, participants must decide if the object in the center and the location of the target in the periphery were identical to the "stimulus" screen. Widespread bilateral whole-brain activation was observed when activation patterns of the "probe" contrast were subtracted from the "stimulus" contrast. Conversely, the subtraction of "stimulus" from "probe" was associated with discrete activation patterns consisting of 13 clusters. Additionally, when evaluating the variance associated with task accuracy, specific subregions were identified that may be critical for task performance. Our data elucidate the functional neural correlates of a UFOV-based task, a task used in both cognitive training paradigms and assessment of function.

Effects of Prefrontal Transcranial Direct Current Stimulation on Retention of Performance Gains on an Obstacle Negotiation Task in Older Adults.

OBJECTIVES: Complex walking in older adults can be improved with task practice and might be further enhanced by pairing transcranial direct current stimulation (tDCS) to the dorsolateral prefrontal cortex. We tested the hypothesis that a single session of practice of a complex obstacle negotiation task paired with active tDCS in older adults would produce greater within-session improvements in walking performance and retention of gains, compared to sham tDCS and no tDCS conditions. MATERIALS AND METHODS: A total of 50 older adults (mean age = 74.46 years ± 6.49) with self-reported walking difficulty were randomized to receive either active tDCS (active-tDCS group) or sham tDCS (sham-tDCS group) bilaterally to the dorsolateral prefrontal cortex or no tDCS (no-tDCS group). Each group performed ten practice trials of an obstacle negotiation task at their fastest safe speed. Retention of gains in walking performance was assessed with three trials conducted one week later. Within-session effects of practice and between-session retention effects on obstacle negotiation speed were examined. RESULTS: At the practice session, all three groups exhibited significant within-session gains in walking speed (p ≤ 0.005). However, the gains were significantly greater in the sham-tDCS group than in the active-tDCS and no-tDCS groups (p ≤ 0.03) and were comparable between the active-tDCS and no-tDCS groups (p = 0.89). At one-week follow-up, the active-tDCS group exhibited significant between-session retention of gains and continued "offline" improvement in walking speed (p = 0.005). The active-tDCS group showed significantly greater retention of gains than the no-tDCS (p = 0.02) but not the sham-tDCS group (p = 0.24). CONCLUSIONS: Pairing prefrontal active tDCS with a single session of obstacle negotiation practice may enhance one-week retention of gains in walking performance compared to no tDCS. However, the evidence is insufficient to suggest a benefit of active tDCS over sham tDCS for enhancing the gains in walking performance. Additional studies with a multisession intervention design and larger sample size are needed to further investigate these findings. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is NCT03122236.

The Association Between Peripheral Oxytocin Levels and Depressive Symptoms in People With HIV.

OBJECTIVE: Depression is common in people with HIV (PWH), yet little is known about the mechanisms contributing to depressive symptoms in PWH. Previous research across a range of populations has suggested a relationship between the neuropeptide oxytocin and depressive symptoms, with variable directionality. This article investigated the association between peripheral oxytocin levels and depressive symptoms in PWH. METHODS: Unextracted oxytocin serum concentrations were assayed in 79 PWH (44% female, mean age = 34.35 [8.5], mean body mass index = 25.69 [5.46], mean CD4 = 516.60 [271.15]) who also completed the Center for Epidemiologic Studies Depression Scale (CES-D). CES-D items were evaluated in an exploratory factor analysis (EFA), and the relationships between oxytocin, total CES-D score, and the resulting EFA factors were analyzed with multivariate linear regressions conducted in R. Multiple regression models were used to adjust for age, sex, body mass index, CD4, and education. RESULTS: Contrary to hypothesized, higher peripheral oxytocin levels were associated with higher CES-D total scores with a small-to-moderate effect size ( ß = 0.26, p = .009). Following Bonferroni correction, oxytocin was not significantly associated with any of the five factors identified from the EFA: depressed affect, positive affect, appetite, cognitive symptoms, or perceived failure ( p values > .042). Small effect sizes were found for the depressed affect ( ß = 0.22) and perceived failure ( ß = 0.21) factors ( p values > .042). CONCLUSIONS: In a sample of predominately Black or African American individuals with HIV, higher oxytocin was associated with higher total depressive symptoms. In addition, this relationship was slightly stronger than those of specific depressive symptoms. These findings warrant further study into the role of oxytocin in mood symptoms within PWH.

Combining Machine Learning and Satellite Observations to Predict Spatial and Temporal Variation of near Surface OH in North American Cities.

The hydroxyl radical (OH) is the primary cleansing agent in the atmosphere. The abundance of OH in cities initiates the removal of local pollutants; therefore, it serves as the key species describing the urban chemical environment. We propose a machine learning (ML) approach as an efficient alternative to OH simulation using a computationally expensive chemical transport model. The ML model is trained on the parameters simulated from the WRF-Chem model, and it suggests that six predictive parameters are capable of explaining 76% of the OH variability. The parameters are the tropospheric NO2 column, the tropospheric HCHO column, J(O1D), H2O, temperature, and pressure. We then use observations of the tropospheric NO2 column and HCHO column from OMI as input to the ML model to enable measurement-based prediction of daily near surface OH at 1:30 pm local time across 49 North American cities over the course of 10 years between 2005 and 2014. The result is validated by comparing the OH predictions to measurements of isoprene, which has a source that is uncorrelated with OH and is removed rapidly and almost exclusively by OH in the daytime. We demonstrate that the predicted OH is, as expected, anticorrelated with isoprene. We also show that this ML model is consistent with our understanding of OH chemistry given the solely data-driven nature.

Elucidating Contributions of Anthropogenic Volatile Organic Compounds and Particulate Matter to Ozone Trends over China.

In China, emissions of ozone (O3)-producing pollutants have been targeted for mitigation to reduce O3 pollution. However, the observed O3 decrease is slower than/opposite to expectations affecting the health of millions of people. For a better understanding of this failure and its connection with anthropogenic emissions, we quantify the summer O3 trends that would have occurred had the weather stayed constant by applying a numerical tool that "de-weathers" observations across 31 urban regions (123 cities and 392 sites) over 8 years. O3 trends are significant (p < 0.05) over 234 sites after de-weathering, contrary to the directly observed trends (only 39 significant due to high meteorology-induced variability). The de-weathered data allow categorizing cities in China into four different groups regarding O3 mitigation, with group 1 exhibiting steady O3 reductions, while group 4 showing significant (p < 0.05) O3 increases. Analysis of the relationships between de-weathered odd oxygen and nitrogen oxides illustrates how the changes in NOx, in anthropogenic volatile organic compounds (VOCs), and reductions in fine particulate matter (PM2.5) affect the O3 trends differently in these groups. While this analysis suggests that VOC reductions are the main driver of O3 decreases in group 1, groups 3 and 4 are primarily affected by decreasing PM2.5, which results in enhanced O3 formation. Our analysis demonstrates both the importance of and possibility for isolating emission-driven changes from climate and weather for interpreting short-term air quality observations.

Two Decades of Changes in Summertime Ozone Production in California's South Coast Air Basin.

Tropospheric ozone (O3) continues to be a threat to human health and agricultural productivity. While O3 control is challenging, tracking underlying formation mechanisms provides insights for regulatory directions. Here, we describe a comprehensive analysis of the effects of changing emissions on O3 formation mechanisms with observational evidence. We present a new approach that provides a quantitative metric for the ozone production rate (OPR) and its sensitivity to precursor levels by interpreting two decades of in situ observations of the six criteria air pollutants(2001-2018). Applying to the South Coast Air Basin (SoCAB), California, we show that by 2016-2018, the basin was at the transition region between nitrogen oxide (NOx)-limited and volatile organic compound (VOC)-limited chemical regimes. Assuming future weather conditions are similar to 2016-2018, we predict that NOx-focused reduction is required to reduce the number of summer days the SoCAB is in violation of the National Ambient Air Quality Standard (70 ppbv) for O3. Roughly, ∼40% (∼60%) NOx reductions are required to reduce the OPR by ∼1.8 ppb/h (∼3.3 ppb/h). This change would reduce the number of violation days from 28 to 20% (10%) in a year, mostly in summertime. Concurrent VOC reductions which reduce the production rate of HOx radicals would also be beneficial.

Observing Annual Trends in Vehicular CO2 Emissions.

Transportation emissions are the largest individual sector of greenhouse gas (GHG) emissions. As such, reducing transportation-related emissions is a primary element of every policy plan to reduce GHG emissions. The Berkeley Environmental Air-quality and CO2 Observation Network (BEACO2N) was designed and deployed with the goal of tracking changes in urban CO2 emissions with high spatial (∼1 km) and temporal (∼1 hr) resolutions while allowing the identification of trends in individual emission sectors. Here, we describe an approach to inferring vehicular CO2 emissions with sufficient precision to constrain annual trends. Measurements from 26 individual BEACO2N sites are combined and synthesized within the framework of a Gaussian plume model. After removing signals from biogenic emissions, we are able to report normalized annual emissions for 2018-2020. A reduction of 7.6 ± 3.5% in vehicular CO2 emissions is inferred for the San Francisco Bay Area over this 2 year period. This result overlaps with, but is slightly larger than, estimates from the 2017 version of the California Air Resources Board EMFAC emissions model, which predicts a 4.7% decrease over these 2 years. This demonstrates the feasibility of independently and rapidly verifying policy-driven reductions in GHG emissions from transportation with atmospheric observations in cities.

Independent Contributions of Dorsolateral Prefrontal Structure and Function to Working Memory in Healthy Older Adults.

Age-related differences in dorsolateral prefrontal cortex (DLPFC) structure and function have each been linked to working memory. However, few studies have integrated multimodal imaging to simultaneously investigate relationships among structure, function, and cognition. We aimed to clarify how specifically DLPFC structure and function contribute to working memory in healthy older adults. In total, 138 participants aged 65-88 underwent 3 T neuroimaging and were divided into higher and lower groups based on a median split of in-scanner n-back task performance. Three a priori spherical DLPFC regions of interest (ROIs) were used to quantify blood-oxygen-level-dependent (BOLD) signal and FreeSurfer-derived surface area, cortical thickness, and white matter volume. Binary logistic regressions adjusting for age, sex, education, and scanner type revealed that greater left and right DLPFC BOLD signal predicted the probability of higher performing group membership (P values<.05). Binary logistic regressions also adjusting for total intracranial volume revealed left DLPFC surface area that significantly predicted the probability of being in the higher performing group (P = 0.017). The left DLPFC BOLD signal and surface area were not significantly associated and did not significantly interact to predict group membership (P values>.05). Importantly, this suggests BOLD signal and surface area may independently contribute to working memory performance in healthy older adults.

Mind Your Heart: Exploring Feasibility, Acceptability, and Preliminary Effects of Phone-Delivered Mindfulness Training on Medication Adherence in Outpatients With Chronic Heart Failure.

BACKGROUND: Mindfulness training (MT) may promote medication adherence in outpatients with heart failure. OBJECTIVE: The aims of this study were to determine the feasibility and acceptability of MT (primary outcomes) and explore effects on medication adherence, functional capacity, cognitive function, depression, and mindfulness skills (secondary outcomes). METHODS: In this pre/post-design study, participants received a 30-minute phone-delivered MT session weekly for 8 weeks. RESULTS: We enrolled 33 outpatients (32% women; 69.7 White; mean age, 60.3 years). Retention was 100%, and session attendance was 91%. Overall, participants (97%) rated MT as enjoyable. Objectively assessed ( P < .05) adherence decreased post intervention, whereas improvements were noted in functional capacity ( P = .05), mindfulness ( P < .05), and cognitive function (reaching significance for Flanker scores). CONCLUSIONS: Phone-delivered MT was feasible and acceptable. Whereas no improvements were noted in medication adherence and depression, cognitive function, functional capacity, and mindfulness levels increased post intervention, suggesting MT may have beneficial effects in outpatients with heart failure.