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Abstract Background Neuronal hyperexcitability and inhibitory interneuron dysfunction are frequently observed in preclinical animal models of Alzheimer’s disease (AD). This study investigates whether these microscale abnormalities explain characteristic large-scale magnetoencephalography (MEG) activity in human early-stage AD patients. Methods To simulate spontaneous electrophysiological activity, we used a whole-brain computational network model comprised of 78 neural masses coupled according to human structural brain topology. We modified relevant model parameters to simulate six literature-based cellular scenarios of AD and compare them to one healthy and six contrast (non-AD-like) scenarios. The parameters include excitability, postsynaptic potentials, and coupling strength of excitatory and inhibitory neuronal populations. Whole-brain spike density and spectral power analyses of the simulated data reveal mechanisms of neuronal hyperactivity that lead to oscillatory changes similar to those observed in MEG data of 18 human prodromal AD patients compared to 18 age-matched subjects with subjective cognitive decline. Results All but one of the AD-like scenarios showed higher spike density levels, and all but one of these scenarios had a lower peak frequency, higher spectral power in slower (theta, 4–8Hz) frequencies, and greater total power. Non-AD-like scenarios showed opposite patterns mainly, including reduced spike density and faster oscillatory activity. Human AD patients showed oscillatory slowing (i.e., higher relative power in the theta band mainly), a trend for lower peak frequency and higher total power compared to controls. Combining model and human data, the findings indicate that neuronal hyperactivity can lead to oscillatory slowing, likely due to hyperexcitation (by hyperexcitability of pyramidal neurons or greater long-range excitatory coupling) and/or disinhibition (by reduced excitability of inhibitory interneurons or weaker local inhibitory coupling strength) in early AD. Conclusions Using a computational brain network model, we link findings from different scales and models and support the hypothesis of early-stage neuronal hyperactivity underlying E/I imbalance and whole-brain network dysfunction in prodromal AD.

We previously observed a range of whole muscle and individual slow and fast myofiber size responses (mean: +4 to −24%) in quadriceps (vastus lateralis) and triceps surae (soleus) muscles of individuals undergoing 70 days of simulated microgravity with or without the NASA SPRINT exercise countermeasures program. The purpose of the current investigation was to further explore, in these same individuals, the content of myonuclei and satellite cells, both of which are key regulators of skeletal muscle mass. Individuals completed 6° head-down-tilt bedrest (BR, n = 9), bedrest with resistance and aerobic exercise (BRE, n = 9), or bedrest with resistance and aerobic exercise and low-dose testosterone (BRE + T, n = 8). The number of myonuclei and satellite cells associated with each slow [myosin heavy chain (MHC) I] and fast (MHC IIa) myofiber in the vastus lateralis was not changed (P > 0.05) pre- to postbedrest within the BR, BRE, or BRE + T groups. Similarly, in the soleus, the number of myonuclei associated with each slow and fast myofiber, and the number of satellite cells associated with each slow myofiber were not changed (P > 0.05) pre- to postbedrest within the BR, BRE, or BRE + T groups. It appears that even with relatively large perturbations in muscle mass over a few months of simulated microgravity, or with partially or completely effective exercise countermeasures, human skeletal muscle tightly regulates the abundance of myonuclei and satellite cells. Thus, exercise countermeasures efficacy for skeletal muscle atrophy appears to be independent of myonuclei and satellite cell abundance. NEW & NOTEWORTHY: This study showed that after 70 days of simulated microgravity, human skeletal muscle does not alter the number of nuclei or satellite cells associated with slow or fast myofibers in the two muscle groups most negatively influenced by microgravity exposure [i.e., quadriceps (vastus lateralis) and triceps surae (soleus)]. Furthermore, the efficacy of exercise countermeasures for maintaining the mass of these muscles does not appear to be related to the myocellular content of nuclei or satellite cells. [ABSTRACT FROM AUTHOR]

The ozone air quality standard is regularly surpassed in the Los Angeles air basin, and efforts to mitigate ozone production have targeted emissions of precursor volatile organic compounds (VOCs), especially from mobile sources. In order to assess how VOC concentrations, emissions, and chemistry have changed over the past decade, VOCs were measured in this study using a Vocus‐2R proton‐transfer reaction time‐of‐flight mass spectrometer in Pasadena, California, downwind of Los Angeles, in summer 2022. Relative to 2010, ambient concentrations of aromatic hydrocarbons have declined at a similar rate as carbon monoxide, suggesting reduced overall emissions from mobile sources. However, the ambient concentrations of oxygenated VOCs have remained similar or increased, suggesting a greater relative importance of oxidation products and other emission sources, such as volatile chemical products whose emissions are largely unregulated. Relative to 2010, the range of measured VOCs was expanded, including higher aromatics and additional volatile chemical products, allowing a better understanding of a wider range of emission sources. Emission ratios relative to carbon monoxide were estimated and compared with 2010 emission ratios. Average measured ozone concentrations were generally comparable between 2022 and 2010; however, at the same temperature, daytime ozone concentrations were lower in 2022 than 2010. Faster photochemistry was observed in 2022, with average hydroxyl radical exposure being ∼68% higher during midday (statistically significant at 95% confidence), although this difference reduces to ∼35% when comparing observations at ambient temperatures of 25–30°C only. Future trends in temperature are important in predicting ozone production. Plain Language Summary: Gas‐phase organic molecules are emitted from many sources including vegetation, cars, cooking, industries, and chemical products (paints, inks, pesticides, deodorant, shampoo, etc.), among others. These emissions oxidize in the atmosphere and contribute to the formation of particles and ozone, which are harmful to human health. To improve air quality, the behavior of these molecules in the atmosphere must be understood, and their sources must be identified, before effective emission reduction policies can be established. In summer 2022, we measured atmospheric concentrations of such molecules in Pasadena, California, downwind of Los Angeles, California, to investigate fresh, unreacted emissions as well as aged, oxidized emissions. Compared to similar measurements made in 2010, emissions from vehicle sources appear to have declined while chemical products have become relatively more important. Atmospheric oxidation of these emissions also appears to have increased relative to 2010, in part due to higher average temperatures and related meteorology. Despite reduced emissions from vehicles, unregulated emissions from chemical products and faster oxidation yielded similar concentrations of secondary products such as ozone. Future air quality improvements will likely require further emission reductions, particularly for chemical products, and such improvements may be offset by rising temperatures due to climate change. Key Points: Concentrations of aromatic hydrocarbons in Los Angeles have declined since 2010 while those of oxygenated volatile organic compounds (VOCs) are similar or higherMidday photochemistry was ∼68% faster in 2022 than 2010 possibly due to higher average temperatures and changes in the NOx‐VOC regimeOzone concentrations were similar between 2010 and 2022 due to the combination of changes in emissions, photochemistry, and meteorology [ABSTRACT FROM AUTHOR]

Seagrass meadows provide many important ecosystem services. They are now recognized as blue carbon ecosystems that are crucial in the mitigation of global climate change. This study was conducted at Mengiat Beach in Bali, Indonesia, where there are extensive seagrass meadows along the shorelines, but also considerable anthropogenic activity that pose threats to the ecosystem. The objectives of this study were to: (1) describe the seagrass community at Mengiat Beach; (2) assess the health status of the seagrass ecosystem; and (3) estimate carbon stocks stored within the ecosystem. Vegetation analysis was conducted to describe the seagrass community in terms of density, cover, biomass and species importance. Spatial Sentinel-2 satellite data with unsupervised classification was used to determine the extent of seagrass meadows. Carbon stocks in sediment and biomass were estimated using the loss on ignition method. The seagrass community at Mengiat Beach consists of at least five different species, dominated by Cymodocea rotundata. The meadows are characterized by high density (588 ind.m-2) and good cover (60.7%). They are considered healthy, with good ecological quality, as indicated by a SEQI (Seagrass Ecological Quality Index) of 0.69. The seagrass ecosystem stores a significant amount of carbon, with 99.23% of it stored in sediment. Total carbon stock in sediment and seagrass biomass is estimated at 133.39 MgC.ha-1. When extrapolated to the total seagrass area of 43.21 ha, the meadows at Mengiat Beach store a total carbon stock of 5.76 GgC, highlighting their potential as high-carbon reservoirs and importance in climate change mitigation efforts. [ABSTRACT FROM AUTHOR]

Contemporary science and religion discourse (SRD) is a large field encompassing various topics, from creationism against evolution to theological anthropology and artificial intelligence, though historically, what is meant by "science" is Western science, and what is meant by "religion" is usually Christianity. Moreover, SRD has been driven mainly from the North American context. The scope of this paper will thus be more focused on Western science and North American Protestant Evangelical Christianity, which hereafter will be referred to as simply Christianity or religion. In this article, I argue that SRD often arises from conflict or intersections where such interdisciplinary dialogue is needed to better understand the topic. However, this also means that topics that seem to agree between religion and science are not discussed in SRD. It is as if the goal of SRD, consciously or unconsciously, is to attain some consensus. Topics that have achieved consensus are not worth interrogating using the interdisciplinary approach of SRD. In this article, I will raise the topic of the holy war on obesity as a case example. From the medical and scientific perspective, obesity is a significant epidemic and problem. Similarly, Christians also see obesity as a problem that their churches can help by reinforcing the need for self-control as a virtue. The alignment of the two fields leaves this subject primarily out of the radar of the academic SRD. Yet I argue here that this unholy alliance needs to be questioned because locating the solution to obesity simply on willpower to lose weight and battle gluttony is short-sighted at best, misleading perhaps, and harmful at worst. This paper calls for a transdisciplinary approach to the SRD on obesity, emphasizing the need to address the multifaceted nature of the problem, which spans physiology, psychology, sociology, economics, culture, and theology. In overlooking the complexity of the problem with its various intersectionalities, both science and religion in SRD have colonized bodies and health. Inherent within this transdisciplinary approach is the exercise of undisciplining SRD and decolonizing bodies. The concept of "undisciplining" involves re-evaluating the problem beyond mere weight loss, addressing interconnected issues such as food supply, government regulations, capitalism, discrimination, and mental health care. The narrative of gluttony as sin, the war metaphor, and the methodologies employed by both religious and scientific communities need to be deconstructed. In conclusion, recognizing the entangled system in which all are complicit, the paper advocates for a more nuanced and comprehensive approach, free from the constraints of traditional disciplinary boundaries and influenced narratives. [ABSTRACT FROM AUTHOR]

Although research on the home literacy environment and its impact on early literacy has long focused on mothers, the past decade has seen a shift in scholarly attention to the role of fathers. Building on this shift, we examined whether the nature of parent–child interactions during shared storybook reading varies with parent gender, child gender and the interaction between the two, and we analysed whether possible differences in the nature of mother– and father–child interactions are related to story comprehension. We made video observations of mothers and fathers within 36 relatively highly educated families reading a storybook with their kindergartener (age 4 – 5) and registered the use of cognitively challenging (i.e. decontextualized) talk during these activities. After each shared reading session, we additionally administered a test assessing children's understanding of the story being read. Two-way mixed ANOVA's revealed no effects of parent gender or child gender on either the use of cognitively challenging talk or children's story comprehension, nor did we find interaction effects of parent and child gender. The extent of cognitively challenging talk was significantly correlated to children's comprehension scores for fathers, but not for mothers. This correlation seems to have masked another association, however: when correlations were computed separately for girls and boys, we found that the proportion of cognitively challenging utterances of both parents was correlated to comprehension scores for boys, but not for girls. The absence of parent gender effects provides further insights into the way mothers and fathers shape interactions during shared reading, but also stresses the need for studies with larger, more diverse samples. The observation that more frequent use of cognitively challenging talk was paralleled by better story comprehension for boys invites further research on the specific effects of shared reading for boys. [ABSTRACT FROM AUTHOR]

The outbreak of COVID-19 promoted strict restrictions to human activities in China, which led to a dramatic decrease in most air pollutant concentrations (e.g., PM2.5, PM10, NOx, SO2 and CO). However, an obvious increase in ozone (O3) concentrations was found during the lockdown period in most urban areas of China. In this study, we conducted field measurements targeting ozone and its key precursors by utilizing a novel proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) in Changzhou, which is representative of the Yangtze River Delta (YRD) city cluster of China. We further applied the integrated methodology including machine learning, an observation-based model (OBM) and sensitivity analysis to obtain insights into the reasons causing the obvious increase in ozone. Major findings include the following: (1) by deweathered calculation, we found changes in precursor emissions contributed 1.46 ppbv to the increase in the observed O3 during the full-lockdown period in 2020, while meteorology constrained 3.0 ppbv of O3 in the full-lockdown period of 2019. (2) By using an OBM, we found that although a significant reduction in O3 precursors was observed during the full-lockdown period, the photochemical formation of O3 was stronger than that during the pre-lockdown period. (3) The NOx/VOC ratio dropped dramatically from 1.84 during the pre-lockdown to 0.79 in the full-lockdown period, which switched O3 formation from a VOC-limited regime to the boundary of a NOx- and VOC-limited regime. Additionally, box model results suggested that the decrease in the NOx/VOC ratio during the full-lockdown period could increase the mean O3 by 2.4 ppbv. Results of this study give insights into the relationship between O3 and its precursors in urban area and demonstrate reasons for the obvious increase in O3 in most urban areas of China during the COVID-19 lockdown period. This study also underlines the necessity of controlling anthropogenic oxygenated volatile organic compounds (OVOCs), alkenes and aromatics in the sustained campaign of reducing O3 pollution in China.

Abstract Background Screening methods for detecting Ultra High Risk status (UHR) or psychosis should be improved, especially in adolescent samples. We therefore tested whether the Child Behavior Checklist (CBCL) and the Youth Self Report (YSR) add value to the Prodromal Questionnaire-16 items version (PQ-16) for detecting UHR status or psychosis. Methods We included help-seeking adolescents who had completed the PQ-16, YSR, CBCL, and a Comprehensive Assessment of an At Risk Mental States (CAARMS) interview, and used independent samples t-tests and binary logistic regression analyses to determine the scales contributing to the prediction of UHR status or of having reached the psychosis threshold (PT). Cutoff scores were determined using ROC analyses. Results Our sample comprised 270 help-seeking adolescents (mean age 14.67; SD 1.56, range 12–17); 67.8% were girls and 66.3% were of Dutch origin. The Thought Problems syndrome scales of both the YSR and the CBCL best predicted UHR or PT, and had screening values comparable to the PQ-16. Other syndrome scales did not improve screening values. Although combining measures reduced the number of false negatives, it also increased the number of adolescents to be interviewed. The best choice was to combine the YSR Thought Problems scale and the PQ-16 as a first-step screener. Conclusions Combining measures improves the detection of UHR or PT in help-seeking adolescents. The Thought Problems subscales of the YSR and CBCL can both be used as a first-step screener in the detection of UHR and/or psychosis. Trial registration Permission was asked according to the rules of the Ethics Committee at Leiden. This study is registered as NL.44180.058.13

Abstract. Organic aerosol (OA) is an important fraction of submicron aerosols. However,it is challenging to predict and attribute the specific organic compounds andsources that lead to observed OA loadings, largely due to contributions fromsecondary production. This is especially true for megacities surrounded bynumerous regional sources that create an OA background. Here, we utilizein situ gas and aerosol observations collected on board the NASA DC-8 duringthe NASA–NIER KORUS-AQ (Korea–United States Air Quality) campaign toinvestigate the sources and hydrocarbon precursors that led to the secondaryOA (SOA) production observed over Seoul. First, we investigate thecontribution of transported OA to total loadings observed over Seoul byusing observations over the Yellow Sea coupled to FLEXPART Lagrangiansimulations. During KORUS-AQ, the average OA loading advected into Seoul was∼1–3 µg sm−3. Second, taking this background intoaccount, the dilution-corrected SOA concentration observed over Seoul was∼140 µgsm-3ppmv-1 at 0.5 equivalent photochemicaldays. This value is at the high end of what has been observed in othermegacities around the world (20–70 µgsm-3ppmv-1 at 0.5equivalent days). For the average OA concentration observed over Seoul(13 µg sm−3), it is clear that production of SOA from locallyemitted precursors is the major source in the region. The importanceof local SOA production was supported by the following observations.(1) FLEXPART source contribution calculations indicate anyhydrocarbons with a lifetime of less than 1 day, which are shown to dominate theobserved SOA production, mainly originate from South Korea. (2) SOAcorrelated strongly with other secondary photochemical species, includingshort-lived species (formaldehyde, peroxy acetyl nitrate, sum of acyl peroxynitrates, dihydroxytoluene, and nitrate aerosol). (3) Results froman airborne oxidation flow reactor (OFR), flown for the first time, show afactor of 4.5 increase in potential SOA concentrations over Seoul versus overthe Yellow Sea, a region where background air masses that are advected intoSeoul can be measured. (4) Box model simulations reproduce SOAobserved over Seoul within 11 % on average and suggest that short-livedhydrocarbons (i.e., xylenes, trimethylbenzenes, and semi-volatile and intermediate-volatility compounds) were the main SOA precursors over Seoul. Toluenealone contributes 9 % of the modeled SOA over Seoul. Finally, along withthese results, we use the metric ΔOA/ΔCO2 toexamine the amount of OA produced per fuel consumed in a megacity, whichshows less variability across the world than ΔOA∕ΔCO.

Primary liver carcinomas with both hepatocytic and cholangiocytic differentiation have been referred to as "combined (or mixed) hepatocellular-cholangiocarcinoma." These tumors, although described over 100 years ago, have attracted greater attention recently because of interest in possible stem cell origin and perhaps because of greater frequency and clinical recognition. Currently, because of a lack of common terminology in the literature, effective treatment and predictable outcome data have been challenging to accrue. This article represents a consensus document from an international community of pathologists, radiologists, and clinicians who have studied and reported on these tumors and recommends a working terminology for diagnostic and research approaches for further study and evaluation.ConclusionIt is recommended that diagnosis is based on routine histopathology with hematoxylin and eosin (H&E); immunostains are supportive, but not essential for diagnosis. (Hepatology 2018;68:113-126).

Despite extensive research on alluvial architecture, there is still a pressing need for data from modern fluvio-deltaic environments. Previous research in the fluvial-dominated proximal and central Rhine–Meuse delta (the Netherlands) has yielded clear spatial trends in alluvial architecture. In this paper, we include the backwater length to establish architectural trends from apex to shoreline. Channel-belt sand body width / thickness ratios and interconnectedness were determined, and the proportions of fluvial channel-belt deposits, fluvial overbank deposits, organics and intertidal deposits were calculated for the complete fluvio-deltaic wedge based on high-resolution geological cross sections. It was found that the average width / thickness ratio of channel-belt sand bodies in the proximal delta is 5 times higher than in the distal delta. Other down-valley trends include an 80 % decrease in the channel deposit proportion (CDP) and a near-constant proportion of overbank deposits. Additionally, interconnectedness in the proximal delta is 3 times higher than in the distal delta. Based on the Rhine–Meuse dataset, we propose a linear empirical function to model the spatial variability of CDP. It is argued that this relationship is driven by four key factors: channel lateral-migration rate, channel-belt longevity, creation of accommodation space and inherited floodplain width. Additionally, it is established that the sensitivity of CDP to changes in the ratio between channel-belt sand body width and floodplain width (normalized channel-belt sand body width) varies spatially and is greatest in the central and distal delta. Furthermore, the proportion of fluvial channel-belt sands is generally an appropriate proxy for the total sand content of fluvio-deltaic successions, although its suitability as a total sand indicator rapidly fades in the distal delta. Characteristics of the backwater zone of the Rhine–Meuse delta are (1) sand body width / thickness ratios that are lower as a consequence of channel narrowing (not deepening), (2) a rapid increase and then a drop in the organic proportion, (3) an increase in the total sand proportion towards the shoreline, and (4) a drop in the connectedness ratio. For this paper, unique high-resolution quantitative data and spatial trends of the alluvial architecture are presented for an entire delta, providing data that can be used to further improve existing fluvial stratigraphy models.

BackgroundeHealth tools such as patient portals and personal health records, also known as patient-centered digital health records, can engage and empower individuals with chronic health conditions. Patients who are highly engaged in their care have improved disease knowledge, self-management skills, and clinical outcomes. ObjectiveWe aimed to systematically review the effects of patient-centered digital health records on clinical and patient-reported outcomes, health care utilization, and satisfaction among patients with chronic conditions and to assess the feasibility and acceptability of their use. MethodsWe searched MEDLINE, Cochrane, CINAHL, Embase, and PsycINFO databases between January 2000 and December 2021. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. Eligible studies were those evaluating digital health records intended for nonhospitalized adult or pediatric patients with a chronic condition. Patients with a high disease burden were a subgroup of interest. Primary outcomes included clinical and patient-reported health outcomes and health care utilization. Secondary outcomes included satisfaction, feasibility, and acceptability. Joanna Briggs Institute critical appraisal tools were used for quality assessment. Two reviewers screened titles, abstracts, and full texts. Associations between health record use and outcomes were categorized as beneficial, neutral or clinically nonrelevant, or undesired. ResultsOf the 7716 unique publications examined, 81 (1%) met the eligibility criteria, with a total of 1,639,556 participants across all studies. The most commonly studied diseases included diabetes mellitus (37/81, 46%), cardiopulmonary conditions (21/81, 26%), and hematology-oncology conditions (14/81, 17%). One-third (24/81, 30%) of the studies were randomized controlled trials. Of the 81 studies that met the eligibility criteria, 16 (20%) were of high methodological quality. Reported outcomes varied across studies. The benefits of patient-centered digital health records were most frequently reported in the category health care utilization on the “use of recommended care services” (10/13, 77%), on the patient-reported outcomes “disease knowledge” (7/10, 70%), “patient engagement” (13/28, 56%), “treatment adherence” (10/18, 56%), and “self-management and self-efficacy” (10/19, 53%), and on the clinical outcome “laboratory parameters,” including HbA1c and low-density lipoprotein (LDL; 16/33, 48%). Beneficial effects on “health-related quality of life” were seen in only 27% (4/15) of studies. Patient satisfaction (28/30, 93%), feasibility (15/19, 97%), and acceptability (23/26, 88%) were positively evaluated. More beneficial effects were reported for digital health records that predominantly focus on active features. Beneficial effects were less frequently observed among patients with a high disease burden and among high-quality studies. No unfavorable effects were observed. ConclusionsThe use of patient-centered digital health records in nonhospitalized individuals with chronic health conditions is potentially associated with considerable beneficial effects on health care utilization, treatment adherence, and self-management or self-efficacy. However, for firm conclusions, more studies of high methodological quality are required. Trial RegistrationPROSPERO (International Prospective Register of Systematic Reviews) CRD42020213285; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=213285

The chemical complexity of atmospheric organic aerosol (OA) has caused substantial uncertainties in understanding its origins and environmental impacts. Here, we provide constraints on OA origins through compositional characterization with molecular-level details. Our results suggest that secondary OA (SOA) from monoterpene oxidation accounts for approximately half of summertime fine OA in Centreville, AL, a forested area in the southeastern United States influenced by anthropogenic pollution. We find that different chemical processes involving nitrogen oxides, during days and nights, play a central role in determining the mass of monoterpene SOA produced. These findings elucidate the strong anthropogenic-biogenic interaction affecting ambient aerosol in the southeastern United States and point out the importance of reducing anthropogenic emissions, especially under a changing climate, where biogenic emissions will likely keep increasing.

Concentrations of atmospheric trace species in the United States have changed dramatically over the past several decades in response to pollution control strategies, shifts in domestic energy policy and economics, and economic development (and resulting emission changes) elsewhere in the world. Reliable projections of the future atmosphere require models to not only accurately describe current atmospheric concentrations, but to do so by representing chemical, physical and biological processes with conceptual and quantitative fidelity. Only through incorporation of the processes controlling emissions and chemical mechanisms that represent the key transformations among reactive molecules can models reliably project the impacts of future policy, energy and climate scenarios. Efforts to properly identify and implement the fundamental and controlling mechanisms in atmospheric models benefit from intensive observation periods, during which collocated measurements of diverse, speciated chemicals in both the gas and condensed phases are obtained. The Southeast Atmosphere Studies (SAS, including SENEX, SOAS, NOMADSS and SEAC4RS) conducted during the summer of 2013 provided an unprecedented opportunity for the atmospheric modeling community to come together to evaluate, diagnose and improve the representation of fundamental climate and air quality processes in models of varying temporal and spatial scales. This paper is aimed at discussing progress in evaluating, diagnosing and improving air quality and climate modeling using comparisons to SAS observations as a guide to thinking about improvements to mechanisms and parameterizations in models. The effort focused primarily on model representation of fundamental atmospheric processes that are essential to the formation of ozone, secondary organic aerosol (SOA) and other trace species in the troposphere, with the ultimate goal of understanding the radiative impacts of these species in the southeast and elsewhere. Here we address questions surrounding four key themes: gas-phase chemistry, aerosol chemistry, regional climate and chemistry interactions, and natural and anthropogenic emissions. We expect this review to serve as a guidance for future modeling efforts.

Dopamine- and tyrosine hydroxylase-immunopositive cells (TH cells) modulate visually driven signals as they flow through retinal photoreceptor, bipolar, and ganglion cells. Previous studies suggested that TH cells release dopamine from varicose axons arborizing in the inner and outer plexiform layers after glutamatergic synapses depolarize TH cell dendrites in the inner plexiform layer and these depolarizations propagate to the varicosities. Although it has been proposed that these excitatory synapses are formed onto appendages resembling dendritic spines, spines have not been found on TH cells of most species examined to date or on TH cell somata that release dopamine when exposed to glutamate receptor agonists. By use of protocols that preserve proximal retinal neuron morphology, we have examined the shape, distribution, and synapse-related immunoreactivity of adult rat TH cells. We report here that TH cell somata, tapering and varicose inner plexiform layer neurites, and varicose outer plexiform layer neurites all bear spines, that some of these spines are immunopositive for glutamate receptor and postsynaptic density proteins (viz., GluR1, GluR4, NR1, PSD-95, and PSD-93), that TH cell somata and tapering neurites are also immunopositive for a γ-aminobutyric acid (GABA) receptor subunit (GABAA Rα1 ), and that a synaptic ribbon-specific protein (RIBEYE) is found adjacent to some colocalizations of GluR1 and TH in the inner plexiform layer. These results identify previously undescribed sites at which glutamatergic and GABAergic inputs may stimulate and inhibit dopamine release, especially at somata and along varicose neurites that emerge from these somata and arborize in various levels of the retina. J. Comp. Neurol. 525:1707-1730, 2017. © 2016 Wiley Periodicals, Inc.

Anthropogenic secondary organic aerosol (ASOA), formed from anthropogenic emissions of organic compounds, constitutes a substantial fraction of the mass of submicron aerosol in populated areas around the world and contributes to poor air quality and premature mortality. However, the precursor sources of ASOA are poorly understood, and there are large uncertainties in the health benefits that might accrue from reducing anthropogenic organic emissions. We show that the production of ASOA in 11 urban areas on three continents is strongly correlated with the reactivity of specific anthropogenic volatile organic compounds. The differences in ASOA production across different cities can be explained by differences in the emissions of aromatics and intermediate- and semi-volatile organic compounds, indicating the importance of controlling these ASOA precursors. With an improved model representation of ASOA driven by the observations, we attribute 340 000 PM2.5-related premature deaths per year to ASOA, which is over an order of magnitude higher than prior studies. A sensitivity case with a more recently proposed model for attributing mortality to PM2.5 (the Global Exposure Mortality Model) results in up to 900 000 deaths. A limitation of this study is the extrapolation from cities with detailed studies and regions where detailed emission inventories are available to other regions where uncertainties in emissions are larger. In addition to further development of institutional air quality management infrastructure, comprehensive air quality campaigns in the countries in South and Central America, Africa, South Asia, and the Middle East are needed for further progress in this area.