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Using data on the geographic location of fracking wells in four U.S. states with mandatory disclosure between 2011 and 2013 — Colorado, Oklahoma, Pennsylvania, and Texas — this paper analyzes the socio-demographic characteristics of people living close to fracking activity. Geo-coded well data from the FracFocus registry are merged to blockgroup-level socio-demographic data from the 2006–2010 American Community Survey and population density and land use data from EPA's Smart Location Database 2010. Different buffer zones around fracking wells are applied to capture effects at different spatial scales and to compare only areas with similar geological properties. We explain the distance to the nearest well within a county with fracking activity or within a buffer zone by race/ethnicity, income, educational attainment, various land-use control variables, and county fixed-effects. We find robust evidence that minorities, especially African Americans, disproportionately live near fracking wells, but less consistent evidence for environmental injustice by income or educational attainment. Strong heterogeneity across states can be observed, suggesting that an improvement in disclosure laws in other states, that would make similar analyses possible, is of great importance. [ABSTRACT FROM AUTHOR]

To predict atmospheric conditions in an urban environment, the land surface processes must be accurately described through the use of detailed land use (LU) and land cover (LC) data. Use of the U.S. Geological Survey (USGS) 25-category data, currently in the Fifth-generation Mesoscale Model (MM5), with the Noah land surface model (LSM) and MRF (medium-range forecast) planetary boundary layer (PBL) schemes resulted in the over-prediction of daytime temperatures in the Houston downtown area due to the inaccurate representation as a completely impervious surface. This bias could be corrected with the addition of canopy water in the urban areas from the evapotranspiration effects of urban vegetation. A more fundamental approach would be to utilize an LULC dataset that represents land surface features accurately. The Texas Forest Service (TFS) LULC dataset established with the LANDSAT satellite imagery correctly represents the Houston–Galveston–Brazoria (HGB) area as mixtures of urban, residential, grass, and forest LULC types. This paper describes how the Noah LSM and PBL schemes in the MM5 were modified to accommodate the TFS-LULC data. Comparisons with various meteorological measurements show that the MM5 simulation made with the high resolution LULC data improves the boundary layer mixing conditions and local wind patterns in the Houston Ship Channel, which is a critically important anthropogenic emission area affecting the HGB air pollution problems. In particular, when the synoptic flows are weak, the improved LULC data simulates the asymmetrically elongated Houston heat island convergence zone influencing the location of the afternoon Gulf of Mexico sea-breeze front and the Galveston Bay breeze flows. This paper is part I of a two-part study and focuses on the meteorological simulation. In part II, effects of using the different meteorological inputs on air quality simulations are discussed. [Copyright &y& Elsevier]

Abstract: Saccharide compositions were measured in ambient particulate matter (PM) samples collected at four sites in Eastern Texas and Central Arizona in an effort to assess the contribution from biomass burning, atmospheric entrainment of soil, and primary biological aerosol particles (PBAPs) in regions with different climate patterns and ecosystems. In spite of the concentration difference, samples from the four study sites showed similar saccharide composition and seasonal variation, with the only exception being trehalose, likely resulting from the influence of local climatic conditions. Comparison of samples at the Arizona site showed different saccharide enrichment patterns between PM2.5 and PM10, which is consistent with their proposed sources as determined by a correlation analysis between observations. A positive matrix factorization (PMF) model was used to resolve three saccharide-related source factors and their relative source contributions to ambient PM using saccharides as tracers. Both the correlation and PMF model results indicate a stronger influence from local biogenic sources on aerosol saccharides at the rural sites than the urban site in Texas, and a greater impact from the PBAP and other biologically derived sources for PM collected in the Arizona location. This paper will provide the first analysis of saccharides in both fine and coarse PM in two US regions with dramatically different climates and ecosystem and provide a characterization of the ambient aerosol sources. [Copyright &y& Elsevier]

Abstract: In this paper, I analyze immigration''s effect on the SAT-scores and college application patterns of high school students in California and Texas. The student-level dataset used is longitudinal in nature and is matched via a unique algorithm to the Census 2000 summary tabulation files to determine immigration at the local census-place level. The Census measure of immigration developed here is extremely specific and improves upon existing immigration measures. Using empirical strategies to account for issues of selection, this essay''s main finding is that the 1990s immigration did not harm, and possibly benefited the student outcomes of U.S. citizens. [Copyright &y& Elsevier]

Public education campaigns, to be successful, must repeat simple, consistent messages over time, using various sources and media. During the 2000, 2001, and 2002 ozone seasons, the North Central Texas Council of Governments (NCTCOG) employed a four-pronged, multimedia approach to educate the public about air quality in the Dallas/Fort Worth (DFW) region. The four-pronged approach included several varied information sources:

The mission operations directorate (MOD) at the Johnson Space Center (JSC) is responsible for the planning and operation of human space flight missions. MOD is being challenged with sustaining and developing new operations capabilities to support increasingly demanding requirements and to improve its processes to accomplish these missions at higher levels of safety, mission success, and effectiveness. Automation is being considered as an enabling technology to meet the aforementioned challenges. The synergistic combination of flight controllers and intelligent software providing the function of ‘operations assistants’ (OA) is being pursued as the key implementation of this technology in the Mission Control Center (MCC).The flight control team (FCT) assesses the condition and operability of the major systems such as electrical power, thermal control, life support, communications, altitude control, and data handling at MCC. OA assist the flight controllers with their tasks of monitoring the status and health of the flight systems. They also help maintain the flight controller''s awareness of the operations being performed during the mission and help assure that operational objectives are being met. The station duty officer (SDO) performs the lead operations role for the International Space Station (ISS) during quiescent times when FCT and the flight director are off-duty. SDOs assess the condition and operability of the major ISS systems. This assessment involves monitoring and controlling several periodic processes on systems such as the electrical power, thermal control, life support, communications, altitude control, and data handling systems. The SDO is also responsible for coordinating operations with the Russian FCT. The OA will help the SDO maintain an awareness of all the processes performed on board and will assist with the responses to anomalous conditions. The OA for this position will support the concept of reduced control center staffing during quiescent times. The purpose of this paper is twofold: (1) to present a unique two-stage specification methodology that combines data flow diagrams and petri nets and (2) to apply the proposed methodology in a complex space station system. [Copyright &y& Elsevier]

This paper presents the synthesized and characterized properties of Eagle Ford Shale (EFS) based on the collected data and laboratory testing results from the canceled Superconducting Super Collider (SSC) site in Texas, USA. Index and mechanical properties of the clay shale were summarized and analyzed statistically. Correlations between index and mechanical properties were established. The estimated shear strength of the intact shale was based on the results of drained triaxial compression and extension tests. The results from uniaxial compression test on vertical and inclined cores and from the triaxial compression and extension tests show that the shale has strength anisotropy. Shear strength along the discontinuities was estimated based on the results from direct shear and triaxial tests on samples with preexisting joints. Constitutive models and bounds of drained shear strengths were evaluated and proposed for intact clay shale, bedding planes, and discontinuities. The information on strength parameters and discontinuities can be used as the basis of future design and numerical studies. [Copyright &y& Elsevier]