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Kim T.J.,Centers for Disease Control and Prevention | Fedan K.B.,Centers for Disease Control and Prevention | Enright P.L.,University izona | Sahakian N.M.,Centers for Disease Control and Prevention | Kreiss K.,Centers for Disease Control and Prevention
American Journal of Industrial Medicine | Year: 2010

Background: Two cases of bronchiolitis obliterans in flavor manufacturing workers prompted California health and labor agencies to initiate industry-wide surveillance. Methods: Companies' physicians submitted cross-sectional questionnaire and spirometry data for 467 workers in 16 workplaces. We compared prevalence ratios of respiratory symptoms, diagnoses, and abnormal spirometry to a general population sample. We calculated odds ratios for risk factors for spirometric obstructive abnormality. Results: Flavoring workers were 2.7 times more likely than the general population to have severe airways obstruction. Risk factors identified for 18 cases with obstruction from six companies included younger age, Hispanic ethnicity, liquid and powder production work, greater company diacetyl usage, and having a coworker with obstruction. Severity of obstruction was related to tenure. At least 12 workers had probable occupational fixed airways obstruction. Conclusions: The flavoring industry risk of severe lung disease justifies lowering flavoring exposures and medical screening for secondary prevention until worker safety is demonstrated. © 2010 Wiley-Liss, Inc. Source

Zhang X.,California Institute of Technology | Nixon C.A.,NASA | Shia R.L.,California Institute of Technology | West R.A.,Jet Propulsion Laboratory | And 5 more authors.
Planetary and Space Science | Year: 2013

We developed a line-by-line heating and cooling rate model for the stratosphere of Jupiter, based on two complete sets of global maps of temperature, C2H2 and C2H6, retrieved from the Cassini and Voyager observations in the latitude and vertical plane, with a careful error analysis. The non-LTE effect is found unimportant on the thermal cooling rate below the 0.01 mbar pressure level. The most important coolants are molecular hydrogen between 10 and 100 mbar, and hydrocarbons, including ethane (C2H6), acetylene (C2H2)and methane(CH4), in the region above. The two-dimensional cooling rate maps are influenced primarily by the temperature structure, and also by the meridional distributions of C2H2 and C2H6.The temperature anomalies at the 1 mbar pressure level in the Cassini data and the strong C2H6 latitudinal contrast in the Voyager epoch are the two most prominent features influencing the cooling rate patterns, with the effect from the 'quasi-quadrennial oscillation (QQO)' thermal structures at ~20 mbar. The globally averaged CH4 heating and cooling rates are not balanced, clearly in the lower stratosphere under 10 mbar, and possibly in the upper stratosphere above the 1 mbar pressure level. Possible heating sources from the gravity wave breaking and aerosols are discussed. The radiative relaxation timescale in the lower stratosphere implies that the temperature profile might not be purely radiatively controlled. © 2013 Elsevier Ltd. Source

Campbell S.D.,University izona | Ziolkowski R.W.,University of Arizona
IEEE Transactions on Antennas and Propagation | Year: 2013

An absorbing metafilm is proposed that is based on a dual-concentric-ring resonator design on a flexible substrate. Detailed simulations and parameter studies demonstrate that it has no polarization dependence and has strong absorption performance even at highly oblique angles of incidence. To explain its behavior, the design and its properties are related to the origin of the physical processes of absorption that occur in naturally occurring materials. Variations of this metafilm absorber design are presented that enhance its performance characteristics and its potential for use in several practical applications. © 2012 IEEE. Source

Engelbracht C.W.,University izona | Hunt L.K.,National institute for astrophysics | Skibba R.A.,University izona | Hinz J.L.,University izona | And 36 more authors.
Astronomy and Astrophysics | Year: 2010

Stellar density and bar strength should affect the temperatures of the cool (T ~ 20-30 K) dust component in the inner regions of galaxies, which implies that the ratio of temperatures in the circumnuclear regions to the disk should depend on Hubble type. We investigate the differences between cool dust temperatures in the central 3 kpc and disk of 13 nearby galaxies by fitting models to measurements between 70 and 500 μm. We attempt to quantify temperature trends in nearby disk galaxies, with archival data from Spitzer/MIPS and new observations with Herschel/SPIRE, which were acquired during the first phases of the Herschel observations for the KINGFISH (Key Insights on Nearby Galaxies: a Far-Infrared Survey with Herschel) sample. We fit single-temperature modified blackbodies to far-infrared and submillimeter measurements of the central and disk regions of galaxies to determine the temperature of the component(s) emitting at those wavelengths. We present the ratio of central-region-to-disk-temperatures of the cool dust component of 13 nearby galaxies as a function of morphological type. We find a significant temperature gradient in the cool dust component in all galaxies, with a mean center-to-disk temperature ratio of 1.15 ± 0.03. The cool dust temperatures in the central ~3 kpc of nearby galaxies are 23 (±3)% hotter for morphological types earlier than Sc, and only 9 (±3)% hotter for later types. The temperature ratio is also correlated with bar strength, with only strongly barred galaxies having a ratio over 1.2. The strong radiation field in the high stellar density of a galactic bulge tends to heat the cool dust component to higher temperatures, at least in early-type spirals with relatively large bulges, especially when paired with a strong bar. © 2010 ESO. Source

Milillo A.,National institute for astrophysics | Orsini S.,National institute for astrophysics | Plainaki C.,National institute for astrophysics | Fierro D.,National institute for astrophysics | And 40 more authors.
Planetary and Space Science | Year: 2013

The detection of Energetic Neutral Particles (ENP) above 10 eV can unequivocally relate a surface-bound exosphere to surface features and can monitor instantaneously the effect of plasma precipitation onto the surface. In the framework of a mission to Jupiter's moons, 2D imaging of plasma precipitation will provide important information on the plasma circulation at the orbits of the moons. Furthermore, a joint measurement of precipitating ions will permit an estimation of the efficiency of the release process. Coupled measurements of ENP and gas composition will improve our knowledge of surface release mechanisms. Ganymede's and Europa's Neutral Imaging Experiment (GENIE) is a high-angular-resolution detector, based on the ToF (Time of Flight) technique, that can detect ENP (energy range > 10 eV-few keV) in the Jupiter environment thanks to an innovative design and technology. Its objective is to map the sites of origin of the ENP of the icy moons' exospheres to investigate the interaction between the surface and the environment. Finally, coupling GENIE with an ion sensor and a mass spectrometer will be an outstanding opportunity to better understand the magnetosphere-moon coupling within the Jupiter system and compare the surface interaction with plasma in the diverse moons. In this paper, the scientific objectives and requirements of ENP detection are summarized and the description of the innovative design concept of GENIE is given, together with the signal and background noise simulation. © 2013 Elsevier Ltd. Source

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