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Aerosol volume size distributions (VSD) retrievals from the Aerosol Robotic Network (AERONET) aerosol monitoring network were obtained during multiple DRAGON (Distributed Regional Aerosol Gridded Observational Network) conducted in Maryland, California, Texas and Colorado from 2011 to 2014. These VSD products were used during field campaigns to make comparisons with near simultaneous in situ sampling from aircraft profiles carried out by the NASA Langley Aerosol Group Experiment (LARGE) team as part of four campaigns comprising the DISCOVER-AQ (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality) experiments. For coincident (±1 hour) measurements there were a total of 91 profile-averaged fine mode size distributions acquired with the LARGE Ultra-High Sensitivity Aerosol Spectrometer (UHSAS) instrument matched to 153 AERONET size distributions retrieved from almucantars at 22 different ground sites. These volume size distributions were characterized by two fine mode parameters, radius of peak concentration (rpeak_conc) and VSD fine mode width (widthfine_mode). The AERONET retrievals of these VSD fine mode parameters, derived from ground-based almucantar sun photometer data, represent ambient humidity values while the LARGE aircraft spiral profile retrievals provide dried aerosol (RH<20%) values. For the combined multiple campaign data set, the average difference in rpeak_conc was 0.033±0.035μm (ambient AERONET values were 15.8% larger than dried LARGE values) and the average difference in width_fine_mode was 0.042±0.039μm (AERONET values were 25.7% larger). When the LARGE retrieved values were adjusted to account for ambient humidification, the agreement notably improved with AERONET-LARGE average differences for rpeak_conc decreasing to 0.011±0.019μm (AERONET values 5.2% larger) and widthfine_mode average differences decreasing to 0.030±0.037μm (AERONET values 15.8% larger). [ABSTRACT FROM AUTHOR]

Abstract: Nitrous acid (HONO), nitric acid (HNO3), and organic aerosol were measured simultaneously atop an 18-story tower in Houston, TX during August and September of 2006. HONO and HNO3 were measured using a mist chamber/ion chromatographic technique, and aerosol size and chemical composition were determined using an Aerodyne quadrupole aerosol mass spectrometer. Observations indicate the potential for a new HONO formation pathway: heterogeneous conversion of HNO3 on the surface of primary organic aerosol (POA). Significant HONO production was observed, with an average of 0.97ppbvevent−1 and a maximum increase of 2.2ppb in 4h. Nine identified events showed clear HNO3 depletion and well-correlated increases in both HONO concentration and POA-dominated aerosol surface area (SA). Linear regression analysis results in correlation coefficients (r 2) of 0.82 for HONO/SA and 0.92 for HONO/HNO3. After correction for established HONO formation pathways, molar increases in excess HONO (HONOexcess) and decreases in HNO3 were nearly balanced, with an average HONOexcess/HNO3 value of 0.97. Deviations from this mole balance indicate that the residual HNO3 formed aerosol-phase nitrate. Aerosol mass spectral analysis suggests that the composition of POA could influence HONO production. Several previously identified aerosol-phase PAH compounds were enriched during events, suggesting their potential importance for heterogeneous HONO formation. [Copyright &y& Elsevier]

The Long-Term Inflow and Structural Test (LIST) program is gathering inflow and structural response data on a modified version of the Micon 65/13 wind turbine at a test site near Bushland, Texas. Data from 491 ten-minute time data records are analyzed here to determine the dependency of fatigue and extreme loads on inflow parameters. Flap and edge bending moment ranges at a blade root are chosen as the structural response variable, z. Various parameters related to the inflow (including, for example, primary parameters such as the mean and standard deviation of the hub-height horizontal wind speed, and secondary parameters such as Reynolds stresses, vertical shear exponent, etc.) are each considered in an inflow parameter vector, x. Time series for the structural response, z, are processed in order to obtain a structural response parameter, y, where in separate statistical studies, y is taken to be either an equivalent fatigue load or an extreme load. This study describes a procedure by which the important "dependencies" of y on the various variables contained in the inflow parameter vector, x, may be determined considering all the available data. These dependencies of y on x are then recomputed using only the data with above-rated mean wind speeds (taken to be approximately 13 m/s). The procedure employed is similar to other studies, but we do not bin the data sets by wind speed since dependencies in one wind speed bin may, be different from those in other bins. Also, our procedure, in sharp contrast to previous studies, examines each inflow parameter in the vector, x, in a sequential analysis, rather than by using multivariate regression. Results from the present study suggest that the primary inflow parameters have a small amount of predictive power in establishing fatigue and extreme loads. In addition, large correlations that exist between several of the secondary parameters individually and each of the primary parameters make it difficult for the secondary parameters to provide any additional explanation of turbine response once the primary parameters have been accounted for. [ABSTRACT FROM AUTHOR]

Abstract: Concentrations of CO, SO2, NO, NO2, and NOY were measured atop the University of Houston''s Moody Tower supersite during the 2006 TexAQS-II Radical and Aerosol Measurement Project (TRAMP). The lowest concentrations of all primary and secondary species were observed in clean marine air in southerly flow. SO2 concentrations were usually low, but increased dramatically in sporadic midday plumes advected from sources in the Houston Ship Channel (HSC), located NE of the site. Concentrations of CO and NOx displayed large diurnal variations in keeping with their co-emission by mobile sources in the Houston Metropolitan Area (HMA). CO/NOx emission ratios of 5.81 ± 0.94 were observed in the morning rush hour. Nighttime concentrations of NOx (NOx = NO + NO2) and NOY (NOY = NO + NO2 + NO3 + HNO3 + HONO + 2∗N2O5 + HO2NO2 + PANs + RONO2 + p-NO3 − + …) were highest in winds from the NNW-NE due to emission from mobile sources. Median ratios of NOx/NOY were approximately 0.9 overnight, reflecting the persistence and/or generation of NOZ (NOZ = NOY − NOx) species in the nighttime Houston boundary layer, and approached unity in the morning rush hour. Daytime concentrations of NOx and NOY were highest in winds from the HSC. NOx/NOY ratios reached their minimum values (median ca 0.63) from 1300 to 1500 CST, near local solar noon, and air masses often retained enough NOx to sustain additional O3 formation farther downwind. HNO3 and PANs comprised the dominant NOZ species in the HMA, and on a median basis represented 17–20% and 12–15% of NOY, respectively, at midday. Concentrations of HNO3, PANs, and NOZ, and fractional contributions of these species to NOY, were at a maximum in NE flow, reflecting the source strength and reactivity of precursor emissions in the HSC. As a result, daytime O3 concentrations were highest in air masses with HSC influence. Overall, our findings confirm the impact of the HSC as a dominant source region within the HMA. A comparison of total NOY measurements with the sum of measured NOY species (NOYi = NOx + HNO3 + PANs + HONO + p-NO3 −) yielded excellent overall agreement during both day ([NOY](ppb) = ([NOYi](ppb)∗1.03 ± 0.16) − 0.42; r 2 = 0.9933) and night ([NOY](ppb) = ([NOYi](ppb)∗1.01 ± 0.16) + 0.18; r 2 = 0.9975). A similar comparison between NOY–NOx concentrations and the sum of NOZi (NOZi = HNO3 + PANs + HONO + p-NO3 −) yielded good overall agreement during the day ([NOZ](ppb) = ([NOZi](ppb)∗1.01 ± 0.30) + 0.044 ppb; r 2 = 0.8527) and at night ([NOZ](ppb) = ([NOZi](ppb)∗1.12 ± 0.69) + 0.16 ppb; r 2 = 0.6899). Median ratios of NOZ/NOZi were near unity during daylight hours but increased to approximately 1.2 overnight, a difference of 0.15–0.50 ppb. Differences between NOZ and NOZi rarely exceeded combined measurement uncertainties, and variations in NOZ/NOZi ratios may have resulted solely from errors in conversion efficiencies of NOY species and changes in NOY composition. However, nighttime NOZ/NOZi ratios and the magnitude of NOZ − NOZi differences were generally consistent with recent observations of ClNO2 in the nocturnal Houston boundary layer. [Copyright &y& Elsevier]

Background: The current study describes the spectrum of community-acquired respiratory infections (CARV) during the first year after lung transplantation (LT). Additionally, we elucidate variables associated with CARV, management strategies utilized, and impact on early and late outcomes., Methods: This was a retrospective study among patients transplanted between 2012 and 2015 (n = 255, mean age 55.6 ± 13.5 years, M: F 152:103). The diagnosis of CARV was based on the multiplex PCR on nasopharyngeal swab samples. Baseline characteristics, post-transplant variables, and outcomes were compared among patients with and without CARV., Results: Eighty CARV infections developed among a quarter of the study group (n = 62, 24.3%). Rhinovirus/enterovirus was the most commonly isolated CARV (n = 24) followed by coronavirus (n = 17) and RSV (n = 9). A significant proportion of episodes (43.8%) required hospitalization. The use of nasal corticosteroids and left single LT was independently associated with an increased risk of CARV. CARV infections did not impact the lung functions during the first year or the CLAD-free survival at 3 years., Conclusions: There is a significant burden of CARV infections during the first year after LT. The use of nasal corticosteroids may increase the risk of CARV infection. CARV infections did not impact outcomes., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

This study tested the feasibility of promoting 1-800-4-CANCER through partnerships with organizations serving African American and Hispanic communities. Small-media and client reminders about human papillomavirus vaccination were made available through local agents to 28 community organizations. Organizations ordered 79 932 resources and distributed them to young women and parents of girls-;African Americans in St Louis, Missouri, and Hispanics in the Lower Rio Grande Valley of Texas. Pre- to postintervention calls to 1-800-4-CANCER increased 38% in these communities, while declining 15% in comparison communities of Kansas City, Missouri, and El Paso, Texas (F = 8.6, P = .004) and 1.4% in the United States as a whole.