Tropospheric ozone (O) is a strong greenhouse gas, particularly in the upper troposphere (UT). Limited observations point to a continuous increase in UT O in recent decades, but the attribution of UT O changes is complicated by large internal climate variability. We show that the anthropogenic signal ("fingerprint") in the patterns of UT O increases is distinguishable from the background noise of internal variability.
View Article and Find Full Text PDFInborn errors of T cell development present a pediatric emergency in which timely curative therapy is informed by molecular diagnosis. In 11 affected patients across four consanguineous kindreds, we detected homozygosity for a single deleterious missense variant in the gene NudC domain-containing 3 () Two infants had severe combined immunodeficiency with the complete absence of T and B cells (TB SCID), whereas nine showed classical features of Omenn syndrome (OS). Restricted antigen receptor gene usage by residual T lymphocytes suggested impaired V(D)J recombination.
View Article and Find Full Text PDFClimate policies that target greenhouse gas emissions can improve air quality by reducing co-emitted air pollutant emissions. However, the extent to which climate policy could contribute to the targets of reducing existing pollution disparities across different populations remains largely unknown. We quantify potential air pollution exposure reductions under U.
View Article and Find Full Text PDFImmune-mediated inflammatory diseases (IMIDs) are commonly associated with complex coexisting conditions, and cardiovascular comorbidities are a common cause of mortality in systemic inflammation. Experimental models of disease provide an opportunity to dissect inflammatory mechanisms that promote damage to vascular tissues affected by comorbidity. Here, we describe methods to recover the thoracic aorta from mice during experimental inflammatory arthritis and assess vascular constriction responses by isometric tension myography.
View Article and Find Full Text PDFAugmented T cell function leading to host damage in autoimmunity is supported by metabolic dysregulation, making targeting immunometabolism an attractive therapeutic avenue. Canagliflozin, a type 2 diabetes drug, is a sodium glucose co-transporter 2 (SGLT2) inhibitor with known off-target effects on glutamate dehydrogenase and complex I. However, the effects of SGLT2 inhibitors on human T cell function have not been extensively explored.
View Article and Find Full Text PDFAir quality and climate change are substantial and linked sustainability challenges, and there is a need for improved tools to assess the implications of addressing these challenges together. Due to the high computational cost of accurately assessing these challenges, integrated assessment models (IAMs) used in policy development often use global- or regional-scale marginal response factors to calculate air quality impacts of climate scenarios. We bridge the gap between IAMs and high-fidelity simulation by developing a computationally efficient approach to quantify how combined climate and air quality interventions affect air quality outcomes, including capturing spatial heterogeneity and complex atmospheric chemistry.
View Article and Find Full Text PDFWe explore how nuclear shut-downs in the United States could affect air pollution, climate and health with existing and alternative grid infrastructure. We develop a dispatch model to estimate emissions of CO, NO and SO from each electricity-generating unit, feeding these emissions into a chemical transport model to calculate effects on ground-level ozone and fine particulate matter (PM). Our scenario of removing nuclear power results in compensation by coal, gas and oil, resulting in increases in PM and ozone that lead to an extra 5,200 annual mortalities.
View Article and Find Full Text PDFHigh-resolution simulations are essential to resolve fine-scale air pollution patterns due to localized emissions, nonlinear chemical feedbacks, and complex meteorology. However, high-resolution global simulations of air quality remain rare, especially of the Global South. Here, we exploit recent developments to the GEOS-Chem model in its high-performance implementation to conduct 1-year simulations in 2015 at cubed-sphere C360 (∼25 km) and C48 (∼200 km) resolutions.
View Article and Find Full Text PDFCrop residue burning contributes to poor air quality and imposes a health burden on India. Despite government bans and other interventions, this practice remains widespread. Here we estimate the impact of changes in agricultural emissions on air quality across India and quantify the potential benefit of district-level actions using an adjoint modeling approach.
View Article and Find Full Text PDFDetailed examination of the impact of modern space launches on the Earth's atmosphere is crucial, given booming investment in the space industry and an anticipated space tourism era. We develop air pollutant emissions inventories for rocket launches and re-entry of reusable components and debris in 2019 and for a speculative space tourism scenario based on the recent billionaire space race. This we include in the global GEOS-Chem model coupled to a radiative transfer model to determine the influence on stratospheric ozone (O) and climate.
View Article and Find Full Text PDFJ Adv Model Earth Syst
June 2022
The NASA Goddard Earth Observing System (GEOS) Composition Forecast (GEOS-CF) provides recent estimates and 5-day forecasts of atmospheric composition to the public in near-real time. To do this, the GEOS Earth system model is coupled with the GEOS-Chem tropospheric-stratospheric unified chemistry extension (UCX) to represent composition from the surface to the top of the GEOS atmosphere (0.01 hPa).
View Article and Find Full Text PDFBackground: Recent antibiotic exposure has previously been associated with poor outcomes following elective surgery. The purpose of this study is to evaluate the impact of prior recent antibiotic exposure in a multicenter cohort of Veterans Affairs patients undergoing elective non-colorectal surgery.
Methods: This is a retrospective cohort study of the Veterans Affairs Surgical Quality Improvement Program, including elective, non-cardiovascular, non-colorectal surgery from 2013 to 2017.
Background: Trauma surgeons face a challenge when deciding whether to resuscitate lethally injured patients whose organ donor status is unknown. Data suggests practice pattern variability in this setting, but little is known about why.
Materials And Methods: We conducted semi-structured interviews with trauma surgeons practicing in Level 1 or 2 trauma centers in Tennessee.
Responses to the COVID-19 outbreak resulted in one of the largest short-term decreases in anthropogenic emissions in modern history. To date, there has been no comprehensive assessment of the impact of lockdowns on air quality and human health. Using global satellite observations and ground measurements from 36 countries in Europe, North America, and East Asia, we find that lockdowns led to reductions in NO concentrations globally, resulting in ~32,000 avoided premature mortalities, including ~21,000 in China.
View Article and Find Full Text PDFBackground: Defining the work performed by emergency general surgery (EGS) surgeons has relied on quantifying surgical interventions, failing to include nonsurgical management performed. The purpose of this study was to identify the extent of operative and nonoperative patient management provided by an EGS service line in response to consults from other hospital providers.
Methods: This is a retrospective descriptive study of all adult patients with an EGS consult request placed from July 1, 2014 to June 30, 2016 at a 1000-bed tertiary referral center.
The radiative forcing resulting from condensation clouds behind aircraft ("contrails") has been estimated to have an effect on the same order of magnitude as all accumulated aviation-attributable CO. However, contrail impacts are highly uncertain, with estimates of total contrail-driven forcing made in the past five years varying by a factor of 4. Two of the key driving uncertainties are the crystal shape and size, which describe the cloud optical properties.
View Article and Find Full Text PDFOutdoor air pollution adversely affects human health and is estimated to be responsible for five to ten per cent of the total annual premature mortality in the contiguous United States. Combustion emissions from a variety of sources, such as power generation or road traffic, make a large contribution to harmful air pollutants such as ozone and fine particulate matter (PM). Efforts to mitigate air pollution have focused mainly on the relationship between local emission sources and local air quality.
View Article and Find Full Text PDFObjective: We present a systematic, sustainable, student-led model for supporting the Surgical Clerkship experience.
Design: Our model includes student-led suturing and knot-tying classes, operating room tours, skills sessions, and shelf review sessions provided systematically for each of 5 Surgical Clerkship blocks in the 2017 to 2018 academic year.
Setting: Vanderbilt University School of Medicine.
Global simulations of atmospheric chemistry are commonly conducted with off-line chemical transport models (CTMs) driven by archived meteorological data from general circulation models (GCMs). The off-line approach has advantages of simplicity and expediency, but incurs errors due to temporal averaging in the meteorological archive and the inability to reproduce the GCM transport algorithms exactly. The CTM simulation is also often conducted at coarser grid resolution than the parent GCM.
View Article and Find Full Text PDFCivil airliner passengers and crew are exposed to elevated levels of radiation relative to being at sea level. Previous studies have assessed the radiation dose received in particular cases or for cohort studies. Here we present the first estimate of the total radiation dose received by the worldwide civilian flying population.
View Article and Find Full Text PDFBlunt cerebrovascular injury (BCVI) includes trauma to the carotid or vertebral vessels and is noted in 0.1% of hospitalized trauma patients without an initial screening system in place. Several important topics must be addressed including determination of the appropriate screening population, the best modality of screening for diagnosis, treatment types, and required follow-up of blunt cerebrovascular injuries.
View Article and Find Full Text PDFTo further pursue the antineoplastic leads offered by our isolation of trans-dihydronarciclasine (1a) and 7-deoxy-trans-dihydronarciclasine (1c) from two medicinal plant species of the Amaryllidaceae family, a practical palladium-catalyzed hydrogenation procedure was developed for the synthesis of these isocarbostyrils from narciclasine (2a) and 7-deoxynarciclasine (2c).
View Article and Find Full Text PDFObjective: The objective of this study was to implement a brief intervention in asthma within a UK national pharmacy chain, and through the use of mystery customers, measure the extent of delivery of the intervention over a 4-month period.
Methods: Mystery customers gathered information on which of the asthma intervention questions were asked, and any lifestyle advice that was given. Additional information was collected on the type of store they visited and the personnel who served them.
As an extension of structure-activity relationship studies of pancratistatin (1), various techniques were first evaluated for separating the mixtures of 7-deoxynarciclasine (2b) and 7-deoxy-trans-dihydronarciclasine (3a) isolated from Hymenocallis littoralis. An efficient solution for that otherwise difficult separation then allowed the lactam carbonyl group of protected (4c and 5c) alcohols 2b and 3a to be reduced employing lithium aluminum hydride. Cleavage (TBAF followed by H2SO4) of the silyl ester/acetonide protected 6a gave amine 8.
View Article and Find Full Text PDFPurpose: To assess changes in serum cytokine levels in patients treated concomitantly with or without systemic low-dose IL-2. Vaccination targeted CTL responses to peptide antigens, and IL-2 was coadministered to expand activated CTL. Paradoxically, CTL responses were diminished in patients after 2 weeks of IL-2.
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