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Abstract The present study considers the role of adjectives and adverbs in stylometric analysis and authorship attribution. Adjectives and adverbs allow both for variations in placement and order (adverbs) and variations in type (adjectives). This preliminary study examines a collection of 25 English-language blogs taken from the Schler Blog corpus, and the Project Gutenberg corpus with specific emphasis on 3 works. Within the blog corpora, the first and last 100 lines were extracted for the purpose of analysis. Project Gutenberg corpora were used in full. All texts were processed and part-of-speech tagged using the Python NLTK package. All adverbs were classified as sentence-initial, preverbal, interverbal, postverbal, sentence-final, or none-of-the-above. The adjectives were classified into types according to the universal English type hierarchy (Cambridge Dictionary Online, 2021; Annear, 1964) manually by one of the authors. Ambiguous adjectives were classified according to their context. For the adverbs, the initial samples were paired and used as training data to attribute the final samples. This resulted in 600 trials under each of five experimental conditions. We were able to attribute authorship with an average accuracy of 9.7% greater than chance across all five conditions. Confirmatory experiments are ongoing with a larger sample of English-language blogs. This strongly suggests that adverbial placement is a useful and novel idiolectal variable for authorship attribution (Juola et al., 2021). For the adjective, differences were found in the type of adjective used by each author. Percent use of each type varied based upon individual preference and subject-matter (e.g. Moby Dick had a large number of adjectives related to size and color). While adverbial order and placement are highly variable, adjectives are subject to rigid restrictions that are not violated across texts and authors. Stylometric differences in adjective use generally involve the type and category of adjectives preferred by the author. Future investigation will focus, likewise, on whether adverbial variation is similarly analyzable by type and category of adverb. 

Abstract Many industries have become increasingly concentrated through mergers and acquisitions, which in health care may have important consequences for spending and outcomes. Using a rich panel of Medicare claims data for nearly one million dialysis patients, we advance the literature on the effects of mergers and acquisitions by studying the precise ways providers change their behavior following an acquisition. We base our empirical analysis on more than 1,200 acquisitions of independent dialysis facilities by large chains over a 12-year period and find that chains transfer several prominent strategies to the facilities they acquire. Most notably, acquired facilities converge to the behavior of their new parent companies by increasing patients’ doses of highly reimbursed drugs, replacing high-skill nurses with less-skilled technicians, and waitlisting fewer patients for kidney transplants. We then show that patients fare worse as a result of these changes: outcomes such as hospitalizations and mortality deteriorate, with our long panel allowing us to identify these effects from within-facility or within-patient variation around the acquisitions. Because overall Medicare spending increases at acquired facilities, mostly as a result of higher drug reimbursements, this decline in quality corresponds to a decline in value for payers. We conclude the article by considering the channels through which acquisitions produce such large changes in provider behavior and outcomes, finding that increased market power cannot explain the decline in quality. Rather, the adoption of the acquiring firm’s strategies and practices drives our main results, with greater economies of scale for drug purchasing responsible for more than half of the change in profits following an acquisition. 

Abstract. To better understand the effects of wildfires on air quality andclimate, it is important to assess the occurrence of chromophoric compoundsin smoke and characterize their optical properties. This study explores themolecular composition of light-absorbing organic aerosol, or brown carbon(BrC), sampled at the Missoula Fire Sciences laboratory as a part of theFIREX Fall 2016 lab intensive. A total of 12 biomass fuels from different planttypes were tested, including gymnosperm (coniferous) and angiosperm(flowering) plants and different ecosystem components such as duff, litter,and canopy. Emitted biomass burning organic aerosol (BBOA) particles werecollected onto Teflon filters and analyzed offline using high-performanceliquid chromatography coupled to a photodiode array spectrophotometer and a high-resolution mass spectrometer(HPLC–PDA–HRMS). Separated BrC chromophores were classified by theirretention times, absorption spectra, integrated absorbance in the near-UVand visible spectral range (300–700 nm), and chemical formulas from theaccurate m∕z measurements. BrC chromophores were grouped into the followingclasses and subclasses: lignin-derived products, which include lignin pyrolysisproducts; distillation products, which include coumarins and flavonoids;nitroaromatics; and polycyclic aromatic hydrocarbons (PAHs). The observedclasses and subclasses were common across most fuel types, although specific BrCchromophores varied based on plant type (gymnosperm or angiosperm) andecosystem component(s) burned. To study the stability of the observed BrCcompounds with respect to photodegradation, BBOA particle samples wereirradiated directly on filters with near UV (300–400 nm) radiation, followedby extraction and HPLC–PDA–HRMS analysis. Lifetimes of individual BrCchromophores depended on the fuel type and the corresponding combustioncondition. Lignin-derived and flavonoid classes of BrC generally hadthe longest lifetimes with respect to UV photodegradation. Moreover,lifetimes for the same type of BrC chromophores varied depending on biomassfuel and combustion conditions. While individual BrC chromophoresdisappeared on a timescale of several days, the overall light absorption bythe sample persisted longer, presumably because the condensed-phasephotochemical processes converted one set of chromophores into anotherwithout complete photobleaching or from undetected BrC chromophores thatphotobleached more slowly. To model the effect of BrC on climate, it isimportant to understand the change in the overall absorption coefficientwith time. We measured the equivalent atmospheric lifetimes of the overallBrC absorption coefficient, which ranged from 10 to 41 d, with subalpinefir having the shortest lifetime and conifer canopies, i.e., juniper, havingthe longest lifetime. BrC emitted from biomass fuel loads encompassingmultiple ecosystem components (litter, shrub, canopy) had absorptionlifetimes on the lower end of the range. These results indicate thatphotobleaching of BBOA by condensed-phase photochemistry isrelatively slow. Competing chemical aging mechanisms, such as heterogeneousoxidation by OH, may be more important for controlling the rate of BrCphotobleaching in BBOA. 

Abstract The NOAA/NASA Fire Influence on Regional to Global Environments and Air Quality (FIREX‐AQ) experiment was a multi‐agency, inter‐disciplinary research effort to: (a) obtain detailed measurements of trace gas and aerosol emissions from wildfires and prescribed fires using aircraft, satellites and ground‐based instruments, (b) make extensive suborbital remote sensing measurements of fire dynamics, (c) assess local, regional, and global modeling of fires, and (d) strengthen connections to observables on the ground such as fuels and fuel consumption and satellite products such as burned area and fire radiative power. From Boise, ID western wildfires were studied with the NASA DC‐8 and two NOAA Twin Otter aircraft. The high‐altitude NASA ER‐2 was deployed from Palmdale, CA to observe some of these fires in conjunction with satellite overpasses and the other aircraft. Further research was conducted on three mobile laboratories and ground sites, and 17 different modeling forecast and analyses products for fire, fuels and air quality and climate implications. From Salina, KS the DC‐8 investigated 87 smaller fires in the Southeast with remote and in‐situ data collection. Sampling by all platforms was designed to measure emissions of trace gases and aerosols with multiple transects to capture the chemical transformation of these emissions and perform remote sensing observations of fire and smoke plumes under day and night conditions. The emissions were linked to fuels consumed and fire radiative power using orbital and suborbital remote sensing observations collected during overflights of the fires and smoke plumes and ground sampling of fuels. 

Abstract. Chamber oxidation experiments conducted at the Fire Sciences Laboratory in 2016 are evaluated to identify important chemical processes contributing to the hydroxy radical (OH) chemistry of biomass burning non-methane organic gases (NMOGs). Based on the decay of primary carbon measured by proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS), it is confirmed that furans and oxygenated aromatics are among the NMOGs emitted from western United States fuel types with the highest reactivities towards OH. The oxidation processes and formation of secondary NMOG masses measured by PTR-ToF-MS and iodide-clustering time-of-flight chemical ionization mass spectrometry (I-CIMS) is interpreted using a box model employing a modified version of the Master Chemical Mechanism (v. 3.3.1) that includes the OH oxidation of furan, 2-methylfuran, 2,5-dimethylfuran, furfural, 5-methylfurfural, and guaiacol. The model supports the assignment of major PTR-ToF-MS and I-CIMS signals to a series of anhydrides and hydroxy furanones formed primarily through furan chemistry. This mechanism is applied to a Lagrangian box model used previously to model a real biomass burning plume. The customized mechanism reproduces the decay of furans and oxygenated aromatics and the formation of secondary NMOGs, such as maleic anhydride. Based on model simulations conducted with and without furans, it is estimated that furans contributed up to 10 % of ozone and over 90 % of maleic anhydride formed within the first 4 h of oxidation. It is shown that maleic anhydride is present in a biomass burning plume transported over several days, which demonstrates the utility of anhydrides as markers for aged biomass burning plumes. 

Abstract. Anthropogenic secondary organic aerosol (ASOA), formed from anthropogenicemissions of organic compounds, constitutes a substantial fraction of themass of submicron aerosol in populated areas around the world andcontributes to poor air quality and premature mortality. However, theprecursor sources of ASOA are poorly understood, and there are largeuncertainties in the health benefits that might accrue from reducinganthropogenic organic emissions. We show that the production of ASOA in 11urban areas on three continents is strongly correlated with the reactivityof specific anthropogenic volatile organic compounds. The differences inASOA production across different cities can be explained by differences inthe emissions of aromatics and intermediate- and semi-volatile organiccompounds, 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 isover an order of magnitude higher than prior studies. A sensitivity casewith a more recently proposed model for attributing mortality to PM2.5(the Global Exposure Mortality Model) results in up to 900 000 deaths. Alimitation of this study is the extrapolation from cities with detailedstudies and regions where detailed emission inventories are available toother regions where uncertainties in emissions are larger. In addition tofurther development of institutional air quality management infrastructure,comprehensive air quality campaigns in the countries in South and CentralAmerica, Africa, South Asia, and the Middle East are needed for furtherprogress in this area. 

Abstract The Neptune Odyssey mission concept is a Flagship-class orbiter and atmospheric probe to the Neptune–Triton system. This bold mission of exploration would orbit an ice-giant planet to study the planet, its rings, small satellites, space environment, and the planet-sized moon Triton. Triton is a captured dwarf planet from the Kuiper Belt, twin of Pluto, and likely ocean world. Odyssey addresses Neptune system-level science, with equal priorities placed on Neptune, its rings, moons, space environment, and Triton. Between Uranus and Neptune, the latter is unique in providing simultaneous access to both an ice giant and a Kuiper Belt dwarf planet. The spacecraft—in a class equivalent to the NASA/ESA/ASI Cassini spacecraft—would launch by 2031 on a Space Launch System or equivalent launch vehicle and utilize a Jupiter gravity assist for a 12 yr cruise to Neptune and a 4 yr prime orbital mission; alternatively a launch after 2031 would have a 16 yr direct-to-Neptune cruise phase. Our solution provides annual launch opportunities and allows for an easy upgrade to the shorter (12 yr) cruise. Odyssey would orbit Neptune retrograde (prograde with respect to Triton), using the moon's gravity to shape the orbital tour and allow coverage of Triton, Neptune, and the space environment. The atmospheric entry probe would descend in ∼37 minutes to the 10 bar pressure level in Neptune's atmosphere just before Odyssey's orbit-insertion engine burn. Odyssey's mission would end by conducting a Cassini-like “Grand Finale,” passing inside the rings and ultimately taking a final great plunge into Neptune's atmosphere. 

Dimethyl sulfide (DMS), emitted from the oceans, is the most abundant biological source of sulfur to the marine atmosphere. Atmospheric DMS is oxidized to condensable products that form secondary aerosols that affect Earth’s radiative balance by scattering solar radiation and serving as cloud condensation nuclei. We report the atmospheric discovery of a previously unquantified DMS oxidation product, hydroperoxymethyl thioformate (HPMTF, HOOCH 2 SCHO), identified through global-scale airborne observations that demonstrate it to be a major reservoir of marine sulfur. Observationally constrained model results show that more than 30% of oceanic DMS emitted to the atmosphere forms HPMTF. Coincident particle measurements suggest a strong link between HPMTF concentration and new particle formation and growth. Analyses of these observations show that HPMTF chemistry must be included in atmospheric models to improve representation of key linkages between the biogeochemistry of the ocean, marine aerosol formation and growth, and their combined effects on climate.