G-LiHT: Goddard's LiDAR, Hyperspectral and Thermal Airborne Imager

Scientists at NASA's Goddard Space Flight Center have developed an ultra-portable, low-cost, multi-sensor remote sensing system for studying the form and function of terrestrial ecosystems. G-LiHT integrates two LIDARs, a 905 nanometer single beam profiler and 1550 nm scanner, with a narrowband (1.5 nanometers) VNIR imaging spectrometer and a broadband (8-14 micrometers) thermal imager. The small footprint (approximately 12 centimeters) LIDAR data and approximately 1 meter ground resolution imagery are advantageous for high resolution applications such as the delineation of canopy crowns, characterization of canopy gaps, and the identification of sparse, low-stature vegetation, which is difficult to detect from space-based instruments and large-footprint LiDAR. The hyperspectral and thermal imagery can be used to characterize species composition, variations in biophysical variables (e.g., photosynthetic pigments), surface temperature, and responses to environmental stressors (e.g., heat, moisture loss). Additionally, the combination of LIDAR optical, and thermal data from G-LiHT is being used to assess forest health by sensing differences in foliage density, photosynthetic pigments, and transpiration. Low operating costs (approximately $1 ha) have allowed us to evaluate seasonal differences in LiDAR, passive optical and thermal data, which provides insight into year-round observations from space. Canopy characteristics and tree allometry (e.g., crown height:width, canopy:ground reflectance) derived from G-LiHT data are being used to generate realistic scenes for radiative transfer models, which in turn are being used to improve instrument design and ensure continuity between LiDAR instruments. G-LiHT has been installed and tested in aircraft with fuselage viewports and in a custom wing-mounted pod that allows G-LiHT to be flown on any Cessna 206, a common aircraft in use throughout the world. G-LiHT is currently being used for forest biomass and growth estimation in the CONUS and Mexico in support of NASA's Carbon Monitoring System (CMS) and AMIGA-Carb (AMerican Icesat Glas Assessment of Carbon). For NASA's CMS, wall-to-wall G-LiHT data have been acquired over intensive study sites with historic LiDAR datasets, dense inventory data, stem maps and flux tower observations. For AMIGA-Carb, G-LiHT transects have been acquired over ICESat tracks and USDA-FS inventory plots throughout the CONUS, and similar data will be acquired in Mexico during 2013. This talk will highlight recent science results from continental-scale transects landscape-scale deployments of G-LiHT, as well as seasonal forest dynamics from repeat pass G-LiHT acquisitions

Piping Vibration Analysis.

Tutorialpg. 119-134Excessive piping vibrations are a major cause of machinery downtime, leaks, fatigue failures, high noise, fires, and explosions in refineries and petrochemical plants. Excessive vibration levels usually occur when a mechanical natural frequency of the piping system is excited by some pulsation or mechanical source. The vibration mode shapes usually involve lateral vibrations and/or shell wall radial vibrations. Simplified methods are presented for analyzing lateral and shell wall piping vibrations and judging their severity. The methods are thought to be conservative and are intended to be used as screening criteria to determine if more sophisticated analyses, such as computer stress modelling or strain gage testing are necessary. Frequency factors for calculating the mechanical natural frequencies for the classical piping configurations (uniform straight beams) and various piping bend configurations are presented. Factors are presented to compensate the natural frequency calculations for concentrated and distributed weight effects. The relationships between piping vibration displacement, velocity and stress are presented and criteria for judging the severity of piping vibration in terms of the endurance stress limit are shown. The mechanisms that can excite piping vibrations will be discussed, as well as methods for controlling their severity

Epinecrophylla, a new genus of antwrens (Aves: Passeriformes: Thamnophilidae)

We offer a new generic name for the stipple-throated assemblage of antwrens (Thamnophilidae) currently placed in the genus Myrmotherula. Molecular studies demonstrated that Myrmotherula is polyphyletic, with the stippled-throated group forming a clade that is not sister to any other currently recognized Myrmotherula species. The stipple-throated assemblage is distinguished morphologically by at least one sex having a black throat stippled white or buffy white combined with a comparatively long, unmarked tail, although three populations considered subspecies have lost one of these characters. The distinct evolution of this assemblage is supported by diagnostic behavioral characters derived from foraging behaviors, vocal repertoires, and nest architecture

Discussions and Reviews : Theorizing about theory in international politics

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66906/2/10.1177_002200276000400405.pd

Exploring the Origin and Fate of the Magellanic Stream with Ultraviolet and Optical Absorption

(Abridged) We present an analysis of ionization and metal enrichment in the Magellanic Stream (MS), the nearest gaseous tidal stream, using HST/STIS and FUSE ultraviolet spectroscopy of two background AGN, NGC 7469 and Mrk 335. For NGC 7469, we include optical spectroscopy from VLT/UVES. In both sightlines the MS is detected in low-ion and high-ion absorption. Toward NGC 7469, we measure a MS oxygen abundance [O/H]_MS=[OI/HI]=-1.00+/-0.05(stat)+/-0.08(syst), supporting the view that the Stream originates in the SMC rather than the LMC. We use CLOUDY to model the low-ion phase of the Stream as a photoionized plasma using the observed Si III/Si II and C III/C II ratios. Toward Mrk 335 this yields an ionization parameter log U between -3.45 and -3.15 and a gas density log (n_H/cm^-3) between -2.51 and -2.21. Toward NGC 7469 we derive sub-solar abundance ratios for [Si/O], [Fe/O], and [Al/O], indicating the presence of dust in the MS. The high-ion column densities are too large to be explained by photoionization, but also cannot be explained by a single-temperature collisional-ionization model (equilibrium or non-equilibrium). This suggests the high-ion plasma is multi-phase. Summing over the low-ion and high-ion phases, we derive conservative lower limits on the ratio N(total H II)/N(H I) of >19 toward NGC 7469 and >330 toward Mrk 335, showing that along these two directions the vast majority of the Stream has been ionized. The presence of warm-hot plasma together with the small-scale structure observed at 21 cm provides evidence for an evaporative interaction with the hot Galactic corona. This scenario, predicted by hydrodynamical simulations, suggests that the fate of the MS will be to replenish the Galactic corona with new plasma, rather than to bring neutral fuel to the disk.Comment: Accepted for publication in ApJ. 18 pages, 7 figures, all in colo

Role of intestinal P‐glycoprotein ( mdr1 ) in interpatient variation in the oral bioavailability of cyclosporine

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110064/1/cptclpt1997116.pd

Measuring Five Dimensions of Religiosity Across Adolescence

This paper theorizes and tests a latent variable model of adolescent religiosity in which five dimensions of religiosity are interrelated: religious beliefs, religious exclusivity, external religiosity, private practice, and religious salience. Research often theorizes overlapping and independent influences of single items or dimensions of religiosity on outcomes such as adolescent sexual behavior, but rarely operationalizes the dimensions in a measurement model accounting for their associations with each other and across time. We use longitudinal structural equation modeling (SEM) with latent variables to analyze data from two waves of the National Study of Youth and Religion. We test our hypothesized measurement model as compared to four alternate measurement models and find that our proposed model maintains superior fit. We then discuss the associations between the five dimensions of religiosity we measure and how these change over time. Our findings suggest how future research might better operationalize multiple dimensions of religiosity in studies of the influence of religion in adolescence

Content analysis of elite articulations

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67140/2/10.1177_002200276400800406.pd