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Strong magnetic fields in the cores of stars are expected to significantly modify the behavior of gravity waves: this is likely the origin of suppressed dipole modes observed in many red giants. However, a detailed understanding of how such fields alter the spectrum and spatial structure of magnetogravity waves has been elusive. For a dipole field, we analytically characterize the horizontal eigenfunctions of magnetogravity modes, assuming that the wavevector is primarily radial. For axisymmetric modes ($m=0$), the magnetogravity wave eigenfunctions become Hough functions, and they have a radial turning point for sufficiently strong magnetic fields. For non-axisymmetric modes ($m\neq0$), the interaction between the discrete $g$ mode spectrum and a continuum of Alfv\'en waves produces nearly discontinuous features in the fluid displacements at critical latitudes associated with a singularity in the fluid equations. effects. We find that magnetogravity modes cannot propagate in regions with sufficiently strong magnetic fields, instead becoming evanescent. When encountering strong magnetic fields, ingoing gravity waves are likely refracted into outgoing slow magnetic waves. These outgoing waves approach infinite radial wavenumbers, which are likely to be damped efficiently. However, it may be possible for a small fraction of the wave power to escape the stellar core as pure Alfv\'en waves or magnetogravity waves confined to a very narrow equatorial band. The artificially sharp features in the WKB-separated solutions suggest the need for global mode solutions which include small terms neglected in our analysis., Comment: 22 pages, 10 figures, 1 table, comments welcome! (submitted to MNRAS)

DNA methyltransferase 3A (DNMT3A) is ade novocytosine methyltransferase responsible for establishing proper DNA methylation during mammalian development. Loss-of-function (LOF) mutations to DNMT3A, including the hotspot mutation R882H, frequently occur in developmental growth disorders and hematological diseases, including clonal hematopoiesis (CH) and acute myeloid leukemia (AML). Accordingly, identifying mechanisms that activate DNMT3A is of both fundamental and therapeutic interest. Here, we applied a base editor mutational scanning strategy with an improved DNA methylation reporter to systematically identify DNMT3A activating mutations in cells. By integrating an optimized cellular recruitment strategy with paired isogenic cell lines with or without the LOF hotspot R882H mutation, we identify and validate three distinct hyperactivating mutations within or interacting with the regulatory ADD domain of DNMT3A, nominating these regions as potential functional target sites for pharmacological intervention. Notably, these mutations are still activating in the context of a heterozygous R882H mutation. Altogether, we showcase the utility of base editor scanning for discovering functional regions of target proteins.SynopsisUsing base editor mutagenesis and a DNA methylation reporter optimized to find activating mutations, we identify novel hyperactivating mutations in DNMT3A that suggest new mechanisms of allosteric control.

Allostery enables dynamic control of protein function. A paradigmatic example is the tightly orchestrated process of DNA methylation maintenance. Despite the fundamental importance of allosteric sites, their identification remains highly challenging. Here, we perform CRISPR scanning on the essential maintenance methylation machinery—DNMT1 and its partner UHRF1—with the activity-based inhibitor decitabine to uncover allosteric mechanisms regulating DNMT1. In contrast to non-covalent DNMT1 inhibition, activity-based selection implicates numerous regions outside the catalytic domain in DNMT1 function. Through computational analyses, we identify putative mutational hotspots in DNMT1 distal from the active site that encompass mutations spanning a multi-domain autoinhibitory interface and the uncharacterized BAH2 domain. We biochemically characterize these mutations as gain-of-function, exhibiting increased DNMT1 activity. Extrapolating our analysis to UHRF1, we discern putative gain-of-function mutations in multiple domains, including key residues across the autoinhibitory TTD–PBR interface. Collectively, our study highlights the utility of activity-based CRISPR scanning for nominating candidate allosteric sites, and more broadly, introduces new analytical tools that further refine the CRISPR scanning framework.

When main-sequence stars expand into red giants, they are expected to engulf close-in planets. Until now, the absence of planets with short orbital periods around post-expansion, core-helium-burning red giants has been interpreted as evidence that short-period planets around Sun-like stars do not survive the giant expansion phase of their host stars. Here we present the discovery that the giant planet 8 Ursae Minoris b orbits a core-helium-burning red giant. At a distance of only 0.5 au from its host star, the planet would have been engulfed by its host star, which is predicted by standard single-star evolution to have previously expanded to a radius of 0.7 au. Given the brief lifetime of helium-burning giants, the nearly circular orbit of the planet is challenging to reconcile with scenarios in which the planet survives by having a distant orbit initially. Instead, the planet may have avoided engulfment through a stellar merger that either altered the evolution of the host star or produced 8 Ursae Minoris b as a second-generation planet. This system shows that core-helium-burning red giants can harbour close planets and provides evidence for the role of non-canonical stellar evolution in the extended survival of late-stage exoplanetary systems., Comment: Published in Nature on 28 June 2023. In press

This paper estimates that pollution damages avoidable by solar capacity vary considerably across zip codes in the United States and that they are uncorrelated with solar subsidy levels in e...

The genome can be divided into two spatially segregated compartments, A and B,1,2 which broadly partition active and inactive chromatin states, respectively. Constitutive heterochromatin is predominantly located within the B compartment and comprises chromatin that is in close contact with the nuclear lamina.3–5 By contrast, facultative heterochromatin marked by H3K27me3 can span both compartments.2–5 How epigenetic modifications, A/B compartmentalization, and lamina association collectively maintain heterochromatin architecture and function remains unclear.6,7 Here we developed an approach termed Lamina-Inducible Methylation and Hi-C (LIMe-Hi-C) that jointly measures chromosome conformation, DNA methylation, and nuclear lamina positioning. Through this approach, we identified topologically distinct A/B sub-compartments characterized by high levels of H3K27me3 and differing degrees of lamina association. To study the regulation of these sub-compartments, we inhibited Polycomb repressive complex 2 (PRC2), revealing that H3K27me3 is an essential factor in sub-compartment segregation. Unexpectedly, PRC2 inhibition also elicited broad gains in lamina association and constitutive heterochromatin spreading into H3K27me3-marked B sub-compartment regions. Consistent with repositioning to the lamina, genes originally marked with H3K27me3 in the B compartment, but not in the A compartment, remained largely repressed, suggesting that constitutive heterochromatin spreading can compensate for loss of H3K27me3 at a transcriptional level. These findings demonstrate that Polycomb sub-compartments and their antagonism with nuclear lamina association are fundamental organizational features of genome structure. More broadly, by jointly measuring nuclear position and Hi-C contacts, our study demonstrates how dynamic changes in compartmentalization and nuclear lamina association represent distinct but interdependent modes of heterochromatin regulation.

DNA methylation is critical for regulating gene expression, necessitating its accurate placement by enzymes such as the DNA methyltransferase DNMT3A. Dysregulation of this process is known to cause aberrant development and oncogenesis, yet how DNMT3A is regulated holistically by its three domains remains challenging to study. Here, we integrate base editing with a DNA methylation reporter to perform in situ mutational scanning of DNMT3A in cells. We identify mutations throughout the protein that perturb function, including ones at an interdomain interface that block allosteric activation. Unexpectedly, we also find mutations in the PWWP domain, a histone reader, that modulate enzyme activity despite preserving histone recognition and protein stability. These effects arise from altered PWWP domain DNA affinity, which we show is a noncanonical function required for full activity in cells. Our findings highlight mechanisms of interdomain crosstalk and demonstrate a generalizable strategy to probe sequence-activity relationships of nonessential chromatin regulators.

We determine the change in air pollution damages from U.S. power plant emissions over 2010 to 2017. Annual damages fell from $245 billion to $133 billion over this period, with most of the decline occurring in the East. Decomposition shows that changes in emissions rates reduced damages by $63 billion, changes in generation shares reduced damages by $60 billion, and a reduction in fossil generation reduced damages by $25 billion. However, changes in damage valuations per ton of emissions increased damages by $35 billion. We estimate that marginal damages declined in the East from about 9¢ per kWh in 2010 to 6¢ in 2017. This decrease is slower than the decrease in total damages. Despite little or no change in total damages in the West and Texas, marginal damages increased. The environmental benefit of electric vehicles increased so that they are now cleaner than gasoline vehicles on average, though substantial heterogeneity remains. The environmental benefit of solar panels decreased in the East but increased elsewhere.

Air quality in the United States has dramatically improved, yet exposure to air pollution is still associated with 100000–200000 deaths annually. Reducing the number of deaths effectively, efficien...

Improved air quality and human health are often discussed as "co-benefits" of mitigating climate change, yet they are rarely considered when designing or implementing climate policies. We analyze the implications of integrating health and climate when determining the best locations for replacing power plants with new wind, solar, or natural gas to meet a CO

Background: Regulatory analyses of air pollution policies require the use of concentration–response functions and underlying health data to estimate the mortality and morbidity effects, as well as the resulting benefits, associated with policy-related changes in fine particulate matter ≤2.5μm (PM2.5)]. Common practice by U.S. federal agencies involves using underlying health data and concentration–response functions that are not differentiated by racial/ethnic group. Objectives: We aim to explore the policy implications of using race/ethnicity-specific concentration–response functions and mortality data in comparison to standard approaches when estimating the impact of air pollution on non-White racial/ethnic subgroups. Methods: Using new estimates from the epidemiological literature on race/ethnicity-specific concentration–response functions paired with race/ethnicity-specific mortality rates, we estimated the mortality impacts of air pollution from all sources from a uniform increase in concentrations and from the regulations imposed by the Mercury Air Toxics Standards. Results: Use of race/ethnicity-specific information increased PM2.5-related premature mortality estimates in older populations by 9% and among older Black Americans by 150% for all-source pollution exposure. Under a uniform degradation of air quality and race/ethnicity-specific information, older Black Americans were found to have approximately 3 times higher mortality relative to White Americans, which is obscured under a non–race/ethnicity-specific modeling approach. Standard approaches of using non–racial/ethnic specific information underestimate the benefits of the Mercury Air Toxics Standards to older Black Americans by almost 60% and overestimate the benefits to older White Americans by 14% relative to using a race/ethnicity-specific modeling approach. Discussion: Policy analyses incorporating race/ethnicity-specific concentration–response functions and mortality data relative to nondifferentiated inputs underestimate the overall magnitude of PM2.5 mortality burden and the disparity in impacts on older Black American populations. Based on our results, we recommend that the best available race/ethnicity-specific inputs are used in regulatory assessments to understand and reduce environmental injustices. https://doi.org/10.1289/EHP9001

Investing according to environmental, social, and governance (ESG) criteria is gaining momentum. Most environmental performance indices focus only on the tonnage of carbon dioxide (CO₂) emissions. This paper proposes an index covering eight pollutants expressed in monetary damage. Inclusion of multiple pollutants reflects a broader range of reputational and regulatory risks. Monetization appropriately weights emissions. CO₂ dominates the mass of other pollutants, yet the marginal damages from other pollutants are larger than CO₂. In the U.S. utility sector from 2014 to 2017, indices which only track CO₂ mischaracterize firms’ environmental performance and underestimate its effect on financial outcomes relative to the multipollutant index. Dirtier firms exhibit lower share prices and higher forward returns. The effect is twice as large for the multipollutant index compared to CO₂. Analysts’ earnings forecasts for dirtier firms systematically undershoot actuals. Earnings errors are between three and five times more sensitive to the multipollutant index than to CO₂. The multipollutant index may suggest new management strategies to financial market participants relative to those based on carbon intensity. ESG disclosure standards based on the new index are more likely to affect financial outcomes, capital allocation decisions, and firm behavior than disclosure of carbon intensity.

We examine the real effects of the Greenhouse Gas Reporting Program (GHGRP) on electric power plants in the United States. Starting in 2010, the GHGRP requires both the reporting of greenhouse gas emissions by facilities emitting more than 25,000 metric tons of carbon dioxide per year to the Environmental Protection Agency and the public dissemination of the reported data in a comprehensive and accessible manner. Using a difference-in-difference research design, we find that power plants that are subject to the GHGRP reduced carbon dioxide emission rates by 7%. The effect is stronger for plants owned by publicly traded firms. We detect evidence of strategic behavior by firms that own both GHGRP plants and non-GHGRP plants. Such firms strategically reallocate emissions between plants to reduce GHGRP-disclosed emissions. We interpret this as evidence that the program is costly to the affected firms. Our results offer new evidence that public or shareholder pressure is a primary channel through which mandatory Corporate Social Responsibility (CSR) reporting programs affect firm behavior.

This paper demonstrates how a central bank might operationalize an expanded role inclusive of managing risks from environmental pollution. The analysis introduces the green interest rate (rg) which depends on temporal changes in the pollution intensity of output. This policy instrument reallocates consumption from periods when output is pollution intensive to when output is cleaner. In economies on a cleaning-up path, rg exceeds r*. For those growing more polluted, rg is less than r*. In the U.S. economy from 1957 to 2016, rg exceeded r* by 50 basis points. Federal environmental policy reversed the orientation between rg and r*. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Natural gas has become the largest fuel source for electricity generation in the United States and accounts for a third of energy production and consumption. However, the environmental and socioeconomic impacts across the supply chain and over the boom-and-bust cycle have not been comprehensively characterized. To provide insight for long-term decision making for energy transitions, we estimate the cumulative impacts of the shale gas boom in the Appalachian basin from 2004 to 2016 on air quality, climate change, and employment. We find that air quality impacts (1200 to 4600 deaths; $23B +99%/−164%) and employment impacts (469,000 job-years ±30%; $21B ±30%) follow the boom-and-bust cycle, while climate impacts ($12B to $94B) persist for generations well beyond the period of natural gas activity. Employment effects concentrate in rural areas where production occurs. However, almost half of cumulative premature mortality due to air pollution is downwind of these areas, occurring in urban regions of the Northeast. The cumulative temperature impacts of methane and carbon dioxide over a 30-year time horizon are nearly equivalent, but over the long term, the cumulative climate impact is largely due to carbon dioxide. We estimate that a tax on production of $2 per thousand cubic foot (+172%/−76%) would compensate for cumulative climate and air quality externalities across the supply chain.

Most developed economies invest in public goods such as national defense, education, infrastructure, and the environment. Discount rates used to evaluate such projects should reflect the rate of return on the current mix of investment opportunities. Rates derived from the productivity of private capital neglect returns beyond the market boundary. The present paper derives discount rates using an augmented measure of national income inclusive of non-market goods. In an empirical application focusing on air pollution and climate damages in the United States economy, the paper reports that the difference between augmented and market discount rates averages 0.3 percentage points from 1999 to 2014.

This paper quantifies the impact of environmental policy on income inequality. We focus on the Clean Air act and the National Ambient Air Quality standards for fine particulate matter and ozone. Using a matched difference-in-differences estimator, we find evidence that both standards increased inequality in market income and a measure of income that deducts per-capita air pollution damage from adjusted gross income. While pollution standards can reduce pollution levels and thus result in significant environmental benefits in aggregate, our findings suggest that these standards appear to distort the distribution of economic resources in complex, and at times unfortunate, ways.

We examine distributional effects of changes in local air pollution from driving electric vehicles in the United States. An econometric model estimates power plant emissions and an integrat...

Numerical and observational evidence suggests that massive white dwarfs dominate the innermost regions of core-collapsed globular clusters by both number and total mass. Using NGC 6397 as a test case, we constrain the features of white dwarf populations in core-collapsed clusters, both at present day and throughout their lifetimes. The dynamics of these white dwarf subsystems have a number of astrophysical implications. We demonstrate that the collapse of globular cluster cores is ultimately halted by the dynamical burning of white dwarf binaries. We predict core-collapsed clusters in the local universe yield a white dwarf merger rate of $\mathcal{O}(10\rm{)\,Gpc}^{-3}\,\rm{yr}^{-1}$, roughly $0.1-1\%$ of the observed Type Ia supernova rate. We show that prior to merger, inspiraling white dwarf binaries will be observable as gravitational wave sources at milli- and decihertz frequencies. Over $90\%$ of these mergers have a total mass greater than the Chandrasekhar limit. If the merger/collision remnants are not destroyed completely in an explosive transient, we argue the remnants may be observed in core-collapsed clusters as either young neutron stars/pulsars/magnetars (in the event of accretion-induced collapse) or as young massive white dwarfs offset from the standard white dwarf cooling sequence. Finally, we show collisions between white dwarfs and main sequence stars, which may be detectable as bright transients, occur at a rate of $\mathcal{O}(100\rm{)\,Gpc}^{-3}\,\rm{yr}^{-1}$ in the local universe. We find that these collisions lead to depletion of blue straggler stars and main sequence star binaries in the centers of core-collapsed clusters., Comment: Submitted to ApJ, 26 pages, 12 figures, 3 tables. Comments welcome

We examine the real effects of the Greenhouse Gas Reporting Program (GHGRP) on electric power plants in the United States. Starting in 2010, the GHGRP requires both the reporting of greenhouse gas emissions by facilities emitting more than 25,000 metric tons of carbon dioxide per year to the Environmental Protection Agency and the public dissemination of the reported data in a comprehensive and accessible manner. Using a difference-in-difference research design, we find that power plants that are subject to the GHGRP reduced carbon dioxide emission rates by 7%. The effect is stronger for plants owned by publicly traded firms. We detect evidence of strategic behavior by firms that own both GHGRP plants and non-GHGRP plants. Such firms strategically reallocate emissions between plants to reduce GHGRP-disclosed emissions. We interpret this as evidence that the program is costly to the affected firms. Our results offer new evidence that public or shareholder pressure is a primary channel through which mandatory Corporate Social Responsibility (CSR) reporting programs affect firm behavior. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

We present three findings on the effects of environmental regulation on the municipal bond market. First, yields increase (decrease) after a new standard is proposed (finalized), consistent with the resolution of regulatory uncertainty. Second, around annual compliance announcements, yields fall for counties that remain in compliance but increase for newly noncompliant counties. Third, yields are substantially higher for bonds from counties just above the pollution threshold relative to counties just below the threshold. Our findings suggest that increases in regulatory stringency or uncertainty over future environmental policy increase the cost of municipal debt raised to fund critical infrastructure.

Trees provide critical contributions to human well-being. They sequester and store greenhouse gasses, filter air pollutants, provide wood, food, and other products, among other benefits. These benefits are threatened by climate change, fires, pests and pathogens. To quantify the current value of the flow of ecosystem services from U.S. trees, and the threats they face, we combine macroevolutionary and economic valuation approaches using spatially explicit data about tree species and lineages. We find that the value of five key ecosystem services with adequate data generated by US trees is $114 billion per annum (low: $85 B; high: $137 B; 2010 USD). The non-market value of trees from carbon storage and air pollution removal far exceed their commercial value from wood products and food crops. Two lineages—pines and oaks—account for 42% of the value of these services. The majority of species face threats from climate change, many face increasing fire risk, and known pests and pathogens threaten 40% of total woody biomass. The most valuable US tree species and lineages are among those most threatened by known pests and pathogens, with species most valuable for carbon storage most at risk from increasing fire threat. High turnover of tree species across the continent results in a diverse set of species distributed across the tree of life contributing to ecosystem services in the U.S. The high diversity of taxa across U.S. forests may be important in buffering ecosystem service losses if and when the most valuable lineages are compromised.

A persistent issue in environmental economics is whether growth is sustainable. Pollution is a key driver of sustainability, which we define as an economy exhibiting falling pollution damages at its balanced growth path. We deduct air pollution and carbon dioxide damages from the national accounts for 163 countries between 1998 and 2018. Global pollution intensity fell from 1998 to 2008, remaining flat thereafter. China highlights the importance of defining sustainability in terms of damages; between 2011 and 2018, physical measures of environmental quality improved, but monetary damage increased by 50 percent. Sustainability based on emissions ignores this rise in damage.

The Boltzmann equation provides a rigorous description of gas flows at all degrees of gas rarefaction. Asymptotic analyses of this equation yield valuable insight into the physical mechanisms underlying gas flows. In this article, we report an asymptotic analysis of the Boltzmann-BGK equation for a slightly rarefied gas when the acoustic wavelength is comparable to the macroscopic characteristic length scale of the flow. This is performed using a three-way matched asymptotic expansion, which accounts for the Knudsen layer, the viscous layer, and the outer Hilbert region - these are separated by asymptotically disparate length scales. Transport equations and boundary conditions for these regions are derived. The utility of this theory is demonstrated by application to three problems: (1) flow generated by uniformly heating two plates, (2) oscillatory thermal creep induced between two plates, and (3) the flow generated by an oscillating sphere. Comparisons to numerical simulations of the Boltzmann-BGK equation and previous asymptotic theories (for long wavelength) are performed. The present theory is distinct from previous asymptotic analyses that implicitly assume long or short acoustic wavelength. This theory is expected to find application in the design and characterization of nanoelectromechanical devices, which often generate acoustic oscillatory flows of a rarefied nature.

A persistent issue in environmental economics is whether growth is sustainable. Pollution is a key driver of sustainability, which we define as an economy exhibiting falling pollution damages at its balanced growth path. We deduct air pollution and carbon dioxide damages from the national accounts for 163 countries between 1998 and 2018. Global pollution intensity fell from 1998 to 2008, remaining flat thereafter. China highlights the importance of defining sustainability in terms of damages; between 2011 and 2018, physical measures of environmental quality improved, but monetary damage increased by 50 percent. Sustainability based on emissions ignores this rise in damage. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

In this study, we develop a methodology for model reduction and selection informed by global sensitivity analysis (GSA) methods. We apply these techniques to a control model that takes systolic blood pressure and thoracic tissue pressure data as inputs and predicts heart rate in response to the Valsalva maneuver (VM). The study compares four GSA methods based on Sobol' indices (SIs) quantifying the parameter influence on the difference between the model output and the heart rate data. The GSA methods include standard scalar SIs determining the average parameter influence over the time interval studied and three time-varying methods analyzing how parameter influence changes over time. The time-varying methods include a new technique, termed limited-memory SIs, predicting parameter influence using a moving window approach. Using the limited-memory SIs, we perform model reduction and selection to analyze the necessity of modeling both the aortic and carotid baroreceptor regions in response to the VM. We compare the original model to three systematically reduced models including (i) the aortic and carotid regions, (ii) the aortic region only, and (iii) the carotid region only. Model selection is done quantitatively using the Akaike and Bayesian Information Criteria and qualitatively by comparing the neurological predictions. Results show that it is necessary to incorporate both the aortic and carotid regions to model the VM.

The COVID-19 pandemic resulted in stay-at-home policies and other social distancing behaviors in the United States in spring of 2020. This paper examines the impact that these actions had on emissions and expected health effects through reduced personal vehicle travel and electricity consumption. Using daily cell phone mobility data for each U.S. county, we find that vehicle travel dropped about 40% by mid-April across the nation. States that imposed stay-at-home policies before March 28 decreased travel slightly more than other states, but travel in all states decreased significantly. Using data on hourly electricity consumption by electricity region (e.g., balancing authority), we find that electricity consumption fell about six percent on average by mid-April with substantial heterogeneity. Given these decreases in travel and electricity use, we estimate the county-level expected improvements in air quality, and therefore expected declines in mortality. Overall, we estimate that, for a month of social distancing, the expected premature deaths due to air pollution from personal vehicle travel and electricity consumption declined by approximately 360 deaths, or about 25% of the baseline 1500 deaths. In addition, we estimate that CO2 emissions from these sources fell by 46 million metric tons (a reduction of approximately 19%) over the same time frame.

Burning coal is known to have environmental costs; this paper demonstrates that the environmental costs of storing and handling coal are also sizable. We find that a 10% increase in the coal stockpiles held by U.S. power plants results in a 0.09% increase in average PM2.5 concentration levels within 25 miles of these plants. Unlike most sources of variation in local air pollution, coal storage and handling impacts PM2.5 but not other pollutants such as SO2 and NO2. Consequently, using coal stockpiles as an instrument, we show that a 10% increase in PM2.5 causes a 1.1% (3.2%) increase in average adult (infant) mortality rates. Using a value of statistical life approach, our estimates indicate that a one ton increase in coal stockpiles results in local air pollution costs of $197. Economic policies that subsidize coal stockpiles highlight the importance of implementing environmental regulations specifically directed at coal storage and handling.

Humans typically self-administer cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) together repeatedly (as in cannabis, cannabis extract, or Sativex®) to relieve pain. It has been suggested that one benefit of the drug combination may be decreased tolerance development. The present study compared the development of tolerance to the antinociceptive effects of THC given alone versus combined with CBD, in rats. THC dose-effect curves on tail withdrawal and paw pressure tests were obtained before and after twice-daily treatment with vehicle or CBD (10 mg/kg), plus vehicle or THC (3.6 mg/kg females; 9.3 mg/kg males) for 4 days. On the first day, THC was more potent in females than males on both nociceptive tests. From pre- to post-chronic (day 1 to day 6), THC potency on the tail withdrawal test decreased more in females than males, and rats that had been treated with CBD + THC repeatedly showed greater rightward/downward shifts of the THC dose-effect curve than rats that had been treated with THC alone. Analysis of blood samples taken after day 6 testing showed that serum THC levels were higher in CBD + THC-treated females than in vehicle + THC-treated females, and THC’s active metabolite 11-OH-THC and its inactive metabolite THC-COOH were lower in CBD + THC-treated rats than in vehicle + THC-treated rats of both sexes. CBD also increased serum levels of the active metabolite cannabinol in both sexes. The decrease in THC’s antinociceptive effects after repeated CBD exposure may be due to CBD-induced inhibition of THC metabolism, and/or antagonism of THC effects that emerges with repeated CBD treatment.

To the extent that pollution and population are spatially correlated, air quality modeling with coarse-resolution horizontal grids may systematically underpredict exposures and disparities in exposure among demographic groups (i.e., environmental injustice). We use InMAP, a reduced-complexity air pollution model, to quantify how estimates of year-2014 fine particulate matter (PM2.5) exposure in the United States vary with model spatial resolution, for a variable-resolution grid. We test five grids, with population-weighted average grid cell edge lengths ranging from 5.9 to 69 km. We find that model-estimated PM2.5 exposure, and exposure disparities among racial-ethnic groups, are lower with coarse grids than with fine grids: switching from our coarsest- to finest-resolution grid increases the calculated population-weighted average exposure by 27% (from 6.6 to 8.3 μg m–3) and causes the estimated difference in average exposure between minorities and whites to increase substantially (from 0.4 to 1.6 μg m–3)...

Despite greater chronic pain prevalence in females compared with males, and the analgesic potential of cannabinoid receptor type 2 (CB2) agonists, CB2 agonists have rarely been tested in females. The aim of the present study was to compare the antinociceptive effects of a CB2-preferring agonist, (2-methyl-1-propyl-1H-indol-3-yl)-1-naphthalenylmethanone (JWH015), in female and male rats against acute pain and persistent inflammatory pain. JWH015 (5-20 mg/kg, intraperitoneally) produced dose-dependent and time-dependent increases in latency to respond on the tail withdrawal and paw pressure tests that did not differ statistically between the sexes. JWH015 dose-dependently decreased locomotor activity in both sexes, but was more potent in females than males. JWH015 produced little catalepsy in either sex. In females, the antinociceptive effects of JWH015 against acute pain were blocked by rimonabant and SR144528, whereas locomotor suppression was antagonized by rimonabant. When administered 3 days after intraplantar injection of complete Freund's adjuvant, JWH015 produced a significantly greater antiallodynic effect in females at the highest dose tested (10 mg/kg, intraperitoneally). Antiallodynic effects of JWH015 were antagonized by rimonabant and SR144528 in both sexes. These studies indicate that systemically administered JWH015 produced antinociception that was both CB1 and CB2 receptor-mediated in both sexes. Unlike [INCREMENT]-9-tetrahydrocannabinol and other nonselective cannabinoid agonists, the CB2-preferring agonist JWH015 may produce more equivalent antinociception in females and males.

This paper demonstrates a new connection between benefit-cost analysis (BCA) and the national income and product accounts. The article computes an augmented measure of output, which is defined as gross domestic product (GDP) less environmental pollution damage. Environmental policy BCA is incorporated directly into the adjusted measure of output in two ways. In a particular time period, damages from pollution emissions are deducted from market GDP in a standard with-and-without policy comparison. Second, secular changes in damages, output (GDP), and correspondingly, in the adjusted measure of output are employed to estimate augmented rates of growth. Comparison to a no-policy counterfactual then yields the effect of the policy on the augmented measure of environmentally adjusted value added (EVA) growth. The empirical results suggest that, in the 30 states that adopted flue-gas desulfurization (FGD) technology between 2005 and 2011, augmented output grew 0.12% more quickly than in a no-scrub counterfactual. Augmented output growth in four states was at least 0.20% more rapid because of the installation of scrubbers. The paper reports that benefits-per-capita from FGD were mildly progressive and that counties with relatively large African American populations incur large benefits from FGD installation.

We combine a theoretical discrete-choice model of vehicle purchases, an econometric analysis of electricity emissions, and the AP2 air pollution model to estimate the geographic variation in the environmental benefits from driving electric vehicles. The second-best electric vehicle purchase subsidy ranges from $2,785 in California to −$4,964 in North Dakota, with a mean of −$1,095. Ninety percent of local environmental externalities from driving electric vehicles in one state are exported to others, implying they may be subsidized locally, even when the environmental benefits are negative overall. Geographically differentiated subsidies can reduce deadweight loss, but only modestly. (JEL D12, D62, H23, L62, Q53, Q54, R11)

After declining by 27.4 percent from 2009 to 2016, annual average fine particulate matter (PM2.5) in the United States in counties with monitors increased by 5.7 percent between 2016 and 20...

The present study gathers prices for firewood and estimates the premium paid for dry fuel, relative to green wood, on a monthly basis from 1922 to 1935. This premium conveys consumers’ willingness-to-pay for a good available for immediate consumption relative to the same good ready for use after roughly one year. Embedded in this premium are consumers’ time preferences. The paper documents time series variation in the dry fuel premium and associated time preference spanning the macroeconomic shocks before, during, and after the Great Depression. The dry fuel premium increased by a factor of four during the recession of 1923 to 1924, and fell by a factor of two following the Great Crash of October 1929. Key factors in determining the premium for dry fuel were variation in wages, inflation, stock market returns, and bond yields. This paper supports the uncertainty hypothesis as an explanation for the precipitous fall in consumption expenditures following the Great Crash of 1929.

This study uses hedonic property models to explore how coastal real estate markets subject to heterogeneous information treatments respond to flood risk. We identify reactions to flood risk, distinctly from price effects due to flood damage, by examining non-local flooding events. Utilizing a difference-in-difference methodology, we test whether the coastal real estate market in New Jersey responds to several well-publicized hurricanes and tropical storms that did not strike the Atlantic seaboard. We find that homes in high flood risk zones situated in towns that participate in public flood awareness activities incur a 7 to 16 percent decrease in price after the non-local shock.

Executive SummaryThis paper estimates an augmented measure of national output inclusive of environmental pollution damage in the US economy over a 60-year period. The paper reports two primary find...

Significance Racial–ethnic disparities in pollution exposure and in consumption of goods and services in the United States are well documented. Some may find it intuitive that, on average, black and Hispanic minorities bear a disproportionate burden from the air pollution caused mainly by non-Hispanic whites, but this effect has not previously been directly established, let alone quantified. Our “pollution inequity” metric is generalizable to other pollution types and provides a simple and intuitive way of expressing a disparity between the pollution that people cause and the pollution to which they are exposed. Our results are timely, given public debate on issues relating to race, equity, and the regulation of pollution., Fine particulate matter (PM2.5) air pollution exposure is the largest environmental health risk factor in the United States. Here, we link PM2.5 exposure to the human activities responsible for PM2.5 pollution. We use these results to explore “pollution inequity”: the difference between the environmental health damage caused by a racial–ethnic group and the damage that group experiences. We show that, in the United States, PM2.5 exposure is disproportionately caused by consumption of goods and services mainly by the non-Hispanic white majority, but disproportionately inhaled by black and Hispanic minorities. On average, non-Hispanic whites experience a “pollution advantage”: They experience ∼17% less air pollution exposure than is caused by their consumption. Blacks and Hispanics on average bear a “pollution burden” of 56% and 63% excess exposure, respectively, relative to the exposure caused by their consumption. The total disparity is caused as much by how much people consume as by how much pollution they breathe. Differences in the types of goods and services consumed by each group are less important. PM2.5 exposures declined ∼50% during 2002–2015 for all three racial–ethnic groups, but pollution inequity has remained high.