Reliability of the Omron HBF-500 Body Composition Monitor

The Omron HBF-500 incorporates both hand-to-hand and foot-to-foot electrical impedance technology. At this time, the authors are not aware of any studies examining the consistency of this monitor. PURPOSE: To assess the reliability of the Omron HBF-500 body composition monitor. METHODS: Twelve men and six women signed an informed consent and participated in the study (32.4±8.7 years, 169.9±7.5 cm, 81.4±15.9 kg, 28.2±5.5 kg.m-2). Participants reported to the laboratory on three separate occasions separated by at least one day and within one week. Participants were asked to refrain from exercise and caffeine on the days of testing and, were asked to not eat a heavy meal three hours prior and to remain normally hydrated. For each trial, height was measured on a Seca 214 portable height rod (Hamburg, Germany) and weight on a Detecto DR 400 digital platform scale (Webb City, MO) without shoes or socks and with one layer of light clothing. Participants then had their body weight and body fat percent (BF%) assessed on the Omron HBF-500 body composition monitor. On the second day of testing, body BF% was also assessed using a Biodynamics 450 bioimpedance analyzer (Seattle, WA). RESULTS: There were no significant differences between the trials for weight assessed on the digital platform scale, F(2,17) = 1.2, p = 0.308, and on the Omron HBF-500, F(2,17) = 2.6, p = 0.086 (Table 1). There were also no significant differences between the trials for body fat assessed on the Omron F(2,17) = 1.0, p = 0.351. Reliability assessed with Cronbach’s alpha was high between the trials of each of the measures (Digital scale (kg), α = 0.999, Omron (kg), α = 0.999, Omron (BF%), α = 0.998). A dependent t-test indicated a significant difference in BF% between the Omron and Biodynamics analyzer (34.2±9.6 and 38.8±12.8, respectively), t(15) = -2.9, p = 0.011. Finally, dependent t-tests revealed body weight measured by the Omron was significantly greater than the Detecto scale in trial 2, t(17) = -6.9, p = 0.001, and in trial 3, t(17) = -7.9, p = 0.001. CONCLUSIONS: The Omron HBF-500 seems to consistently measure body weight and body composition. Although the HBF-500 can be questioned as an accurate measure of body composition, it seems to be a useful tool if one is interested in tracking changes in body weight and BF%

Keck spectroscopy of z=1-3 ULIRGs from the Spitzer SWIRE survey

(Abridged) High-redshift ultra luminous infrared galaxies contribute the bulk of the cosmic IR background and are the best candidates for very massive galaxies in formation at z>1.5. We present Keck/LRIS optical spectroscopy of 35 z>1.4 luminous IR galaxies in the Spitzer Wide-area Infra-Red Extragalactic survey (SWIRE) northern fields (Lockman Hole, ELAIS-N1, ELAIS-N2). The primary targets belong to the ``IR-peak'' class of galaxies, having the 1.6 micron (restframe) stellar feature detected in the IRAC Spitzer channels.The spectral energy distributions of the main targets are thoroughly analyzed, by means of spectro-photometric synthesis and multi-component fits (stars + starburst dust + AGN torus). The IR-peak selection technique is confirmed to successfully select objects above z=1.4, though some of the observed sources lie at lower redshift than expected. Among the 16 galaxies with spectroscopic redshift, 62% host an AGN component, two thirds being type-1 and one third type-2 objects. The selection, limited to r'<24.5, is likely biased to optically-bright AGNs. The SEDs of non-AGN IR-peakers resemble those of starbursts (SFR=20-500 Msun/yr) hosted in massive (M>1e11 Msun) galaxies. The presence of an AGN component provides a plausible explanation for the spectroscopic/photometric redshift discrepancies, as the torus produces an apparent shift of the peak to longer wavelengths. These sources are analyzed in IRAC and optical-IR color spaces. In addition to the IR-peak galaxies, we present redshifts and spectral properties for 150 objects, out of a total of 301 sources on slits.Comment: Accepted for publications on Astronomy and Astrophysics (acceprance date March 8th, 2007). 33 pages. The quality of some figures have been degrade

Chemical Abundances in Field Red Giants from High-Resolution H-Band Spectra using the APOGEE Spectral Linelist

High-resolution H-band spectra of five bright field K, M, and MS giants, obtained from the archives of the Kitt Peak National Observatory (KPNO) Fourier Transform Spectrometer (FTS), are analyzed to determine chemical abundances of 16 elements. The abundances were derived via spectrum synthesis using the detailed linelist prepared for the SDSS III Apache Point Galactic Evolution Experiment (APOGEE), which is a high-resolution near-infrared spectroscopic survey to derive detailed chemical abundance distributions and precise radial velocities for 100,000 red giants sampling all Galactic stellar populations. Measured chemical abundances include the cosmochemically important isotopes 12C, 13C, 14N, and 16O, along with Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu. A comparison of the abundances derived here with published values for these stars reveals consistent results to ~0.1 dex. The APOGEE spectral region and linelist is, thus, well-suited for probing both Galactic chemical evolution, as well as internal nucleosynthesis and mixing in populations of red giants using high-resolution spectroscopy.Comment: Accepted for publication in The Astrophysical Journal. 42 pages, 12 figure

The FAOSTAT database of greenhouse gas emissions from agriculture

Peer reviewedPublisher PD

Baryon Number in Warped GUTs : Model Building and (Dark Matter Related) Phenomenology

In the past year, a new non-supersymmetric framework for electroweak symmetry breaking (with or without Higgs) involving SU(2)_L * SU(2)_R * U(1)_{B-L} in higher dimensional warped geometry has been suggested. In this work, we embed this gauge structure into a GUT such as SO(10) or Pati-Salam. We showed recently (in hep-ph/0403143) that in a warped GUT, a stable Kaluza-Klein fermion can arise as a consequence of imposing proton stability. Here, we specify a complete realistic model where this particle is a weakly interacting right-handed neutrino, and present a detailed study of this new dark matter candidate, providing relic density and detection predictions. We discuss phenomenological aspects associated with the existence of other light (<~ TeV) KK fermions (related to the neutrino), whose lightness is a direct consequence of the top quark's heaviness. The AdS/CFT interpretation of this construction is also presented. Most of our qualitative results do not depend on the nature of the breaking of the electroweak symmetry provided that it happens near the TeV brane.Comment: 61 pages, 12 figures; v2: minor changes; v3: Two additional diagrams in Fig. 10; a numerical factor corrected in section 16.1 (baryogenesis section), corresponding discussion slightly modified but qualitative results unchange

Freshly Formed Dust in the Cassiopeia A Supernova Remnant as Revealed by the Spitzer Space Telescope

We performed Spitzer Infrared Spectrograph mapping observations covering nearly the entire extent of the Cassiopeia A supernova remnant (SNR), producing mid-infrared (5.5-35 micron) spectra every 5-10". Gas lines of Ar, Ne, O, Si, S and Fe, and dust continua were strong for most positions. We identify three distinct ejecta dust populations based on their continuum shapes. The dominant dust continuum shape exhibits a strong peak at 21 micron. A line-free map of 21 micron-peak dust made from the 19-23 micron range closely resembles the [Ar II], [O IV], and [Ne II] ejecta-line maps implying that dust is freshly formed in the ejecta. Spectral fitting implies the presence of SiO2, Mg protosilicates, and FeO grains in these regions. The second dust type exhibits a rising continuum up to 21 micron and then flattens thereafter. This ``weak 21 micron'' dust is likely composed of Al2O3 and C grains. The third dust continuum shape is featureless with a gently rising spectrum and is likely composed of MgSiO3 and either Al2O3 or Fe grains. Using the least massive composition for each of the three dust classes yields a total mass of 0.02 Msun. Using the most-massive composition yields a total mass of 0.054 Msun. The primary uncertainty in the total dust mass stems from the selection of the dust composition necessary for fitting the featureless dust as well as 70 micron flux. The freshly formed dust mass derived from Cas A is sufficient from SNe to explain the lower limit on the dust masses in high redshift galaxies.Comment: 8 figures: Accepted for the publication in Ap

Infrared Constraints on AGN Tori Models

This work focuses on the properties of dusty tori in active galactic nuclei (AGN) derived from the comparison of SDSS type 1 quasars with mid-Infrared (MIR) counterparts and a new, detailed torus model. The infrared data were taken by the Spitzer Wide-area InfraRed Extragalactic (SWIRE) Survey. Basic model parameters are constraint, such as the density law of the graphite and silicate grains, the torus size and its opening angle. A whole variety of optical depths is supported. The favoured models are those with decreasing density with distance from the centre, while there is no clear tendency as to the covering factor, ie small, medium and large covering factors are almost equally distributed. Based on the models that better describe the observed SEDs, properties such as the accretion luminosity, the mass of dust, the inner to outer radius ratio and the hydrogen column density are computed.Comment: 4 pages, 4 figures, to appear in "Infrared Diagnostics of Galaxy Evolution", ASP Conference Series, Pasadena, 14-16 November 200

Accuracy of the Omron HBF-500 Body Composition Monitor

The Omron HBF-500 is a relatively new and inexpensive body composition monitor that incorporates both hand-to-hand and foot-to-foot electrical impedance technology. At this time, the authors are not aware of any studies examining the accuracy of this monitor. PURPOSE: To assess the accuracy of the Omron HBF-500 body composition monitor using the BOD POD as a criterion. METHODS: Sixteen men and 23 women signed an informed consent and participated in the study (22.7±3.7 years, 168.8±9.1 cm, 73.8±17.8 kg, 25.7±5.6 kg.m-2). Participants were asked to refrain from exercise and caffeine on the day of testing, and were asked not eat a heavy meal three hours prior and to remain normally hydrated. Participants removed all jewelry and garments down to tight fitting clothing (swim suits or running tights) and were assessed on the BOD POD and Omron according to manufacturer’s guidelines. RESULTS: The Omron HBF-500 significantly overestimated percent body fat (%BF) by 3.5% compared to the BOD POD (31.7±9.6% and 28.6±9.6%, respectively), t(38) = -6.05, p = 0.001. The Omron HBF-500 also measured weight significantly higher than the BODPOD (74.4±17.7kg and 73.8±17.8kg, respectively), t(38) = -11.2, p = 0.001. Finally, the Omron HBF-500 was significantly correlated with the BOD POD when assessing body fat, r = .93. CONCLUSIONS: Caution should be taken when using the Omron HBF-500 as a measure of body fat. Those who choose to use this instrument should be aware the 3.5% higher reading compared to the BOD POD