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Latino Destinations and Environmental Inequality: Estimated Cancer Risk from Air Toxics in Latino Traditional and New Destinations
Since the 1990s, Latino migration patterns have shifted from traditional destinations to new destinations away from the Mexico border. Scholars note disparities between destinations in housing, crime, and health care, yet no study has examined environmental inequalities. In this article we employ theories of spatial assimilation and environmental inequality to evaluate health risks across Latino destinations by asking the question, is there a difference in estimated cancer risk from air toxics among established, new, and nondestination locations? Using county-level data with spatial lag regression analyses, we find that early new destinations (i.e., counties with significant Latino growth from 1990 to 2000) and recent new destinations (i.e., counties with significant Latino growth from 1990 to 2010) have higher estimated cancer risk from air toxics than established destinations (i.e., counties at or greater than the national average of Latinos in 1990) and nondestinations. The effect remains significant when controlling for various economic indicators
A Preliminary Study of Airplane Performance
Flight tests were carried out at the Langley Field laboratory of the NACA, on several airplanes for the purpose of determining their relative performance with the same engine and the same propeller. The method used consisted in flying each airplane on a level course and measuring the airspeed for the whole range of engine revolutions. In general the results show that a small change in the wing section or the wing area has but a slight effect upon the performance, but changes in those parts which cause the structural resistance have a very important effect
Self-recording portable soil penetrometer
A lightweight portable penetrometer for testing soil characteristics is described. The penetrometer is composed of a handle, data recording, and probe components detachably joined together. The data recording component has an easily removed recording drum which rotates according to the downward force applied on the handle, and a stylus means for marking the drum along its height according to the penetration depth of probe into the soil
Computing the Mertens and Meissel-Mertens constants for sums over arithmetic progressions
We give explicit numerical values with 100 decimal digits for the Mertens
constant involved in the asymptotic formula for and, as a by-product, for the Meissel-Mertens constant
defined as , for , ...,
and .Comment: 12 pages, 6 table
On the Orbital Period of the Intermediate Polar 1WGA J1958.2+3232
Recently, Norton et al. 2002, on the basis of multiwavelength photometry of
1WGA J1958.2+3232, argued that the -1 day alias of the strongest peak in the
power spectrum is the true orbital period of the system, casting doubts on the
period estimated by Zharikov et al. 2001. We re-analyzed this system using our
photometric and spectroscopic data along with the data kindly provided by Andy
Norton and confirm our previous finding. After refining our analysis we find
that the true orbital period of this binary system is 4.35h.Comment: 4 pages, 5 figures, Accepted for publication in A&A Letter
Comment on ``Superconducting PrBa_2Cu_3O_x''
Recently, Zou et al. (Phys. Rev. Lett. 80, 1074, 1998) reported the
observation of bulk superconductivity (SC) for a PrBa_2Cu_3O_x (Pr123) single
crystal grown by the traveling-solvent floating zone (TSFZ) method. The aim of
this Comment is to show the inconsistency of the value of effective magnetic
moment \mu_{eff} reported by Zou et al. (2.92\mu_B) with their magnetic
susceptibility data. The estimation made directly from their data points gives
a considerably smaller value of \mu_{eff}=2.09\mu_B. At the same time the
values of mu_{eff}=2.9\mu_B and 3.1\mu_B were obtained for our Pr123 single
crystals grown by flux method for H||ab-plane and H||c-axis, respectively. This
suggests that Pr occupies only about a half of the RE sites in TSFZ crystal.
The other half of the RE sites is occupied most probably by the nonmagnetic Ba.
Noteworthy, SC with T_c=43 K was observed earlier for
Pr_{0.5}Ca_{0.5}Ba_2Cu_3O_{7-y} thin films. Ba^{2+} has a larger ionic radius
than Pr^{3+} and so the substitution of Ba for Pr could give a natural
explanation not only for the SC in TSFZ Pr123 but also for the elongation of
the distance between the CuO_2 planes observed by Zou et al.Comment: Slightly extended version of Comment accepted to Phys. Rev. Lett.
(v.81, N24, 1998), tentatevely to be publ. 14Dec98. 1 page, REVTex; 1 EPS fi
Pressure Distribution over the Rudder and Fin of an Airplane in Flight
This investigation was carried out by the National Advisory Committee for Aeronautics at the Langley Memorial Aeronautical Laboratory for the purpose of determining the loads which occur on the vertical tail surfaces in flight. The method consisted in measuring the pressures simultaneously at 28 points on the rudder and fin by means of a recording multiple manometer. The results show that the maximum load encountered in stunting was 7 pounds per square foot on the rudder and fin, and it is probable that this might rise to 10 pounds per square foot in a violent barrel roll; but in steady flight the average loads do not exceed 0.6 pound per square foot. The maximum load on the rudder and fin may occur at the same instant as the maximum load on the horizontal tail surfaces and the maximum normal acceleration. The torsional moment about the axis of the fuselage due to the rudder and fin may rise as high as 250 foot-pound. The results obtained from this investigation have a direct application to the design of the rudder, fin, and fuselage
Complete Study of Longitudinal Oscillation of a VE-7 Airplane
This investigation was carried out by the National Advisory Committee for Aeronautics at Langley Field in order to study as closely as possible the behavior of an airplane when it was making a longitudinal oscillation. The airspeed, the altitude, the angle with the horizon and the angle of attack were all recorded simultaneously and the resulting curves plotted to the same time scale. The results show that all the curves are very close to damped sine curves, with the curves for height and angle of attack in phase, that for angle with the horizon leading them by 18 per cent and that for path angle leading them by 25 per cent
New observations of stratospheric N2O5
The unequivocal detection of N2O5 in the stratosphere was reported by Toon et al. based on measurements of the absorption by the N2O5 bands at 1246 and 1720/cm in solar occulation spectra recorded at sunrise near 47 S latitude by the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment during the Spacelab 3 (SL3) shuttle mission. Additional measurements and analysis of stratospheric N2O5 derived from the ATMOS/SL3 spectra are reported. The primary results are the detection and measurement of N2O5 absorption at sunset in the lower stratosphere, the inversion of a precise (approximately 10 percent) N2O5 sunrise vertical distribution between 25.5 and 37.5 km altitude, and the identification and measurement of absorption by the N2O5 743/cm band at sunrise. Assuming 4.32 x 10(sup -17) and 4.36 x 10(sup -17)/cm/molecule/sq cm respectively for the integrated intensities of the 1246 and 743/cm bands at stratospheric temperatures, retrieved volume mixing ratios in parts per billion by volume (ppbv) at sunrise (47 S latitude) are 1.32 + or - 0.34 at 37.5 km, 1.53 + or - 0.35 at 35.5 km, 1.63 + or - 0.36 at 33.5 km, 1.60 + or - 0.34 at 31.5 km, 1.43 + or - 0.30 at 29.5 km, 1.15 + or - 0.24 at 27.5 km, and 0.73 + or - 0.15 at 25.5 km. Retrieved VMRs in ppbv at sunset (30 N latitude) are 0.13 + or - 0.05 at 29.5 km, 0.14 + or - 0.05 at 27.5 km, and 0.10 + or - 0.04 at 25.5 km. Quoted error limits (1 sigma) include the error in the assumed band intensities (approximately 20 percent). Within the error limits of the measurements, the inferred mixing ratios at sunrise agree with diurnal photochemical model predictions obtained by two groups using current photochemical data. The measured mixing ratios at sunset are lower than the model predictions with differences of about a factor of 2 at 25 km altitude
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