2,239 research outputs found
Texas Natural Resources Inventory and Monitoring System (TNRIMS). Applications Verification and ~ transfer (ASVT), Remote Sensing Information Sub system (RSIS): Unival software user's guide
There are not author-identified significant results in this report
Texas Natural Resources Inventory and Monitoring System (TNRIMS), Applications System Verification and Transfer (ASVT), Remote Sensing Information Subsystem (RSIS): Acceptance test procedures
There are no author-identified significant results in this report
Cumulant expansion for phonon contributions to the electron spectral function
We describe an approach for calculations of phonon contributions to the
electron spectral function, including both quasiparticle properties and
satellites. The method is based on a cumulant expansion for the retarded
one-electron Green's function and a many-pole model for the electron
self-energy. The electron-phonon couplings are calculated from the Eliashberg
functions, and the phonon density of states is obtained from a Lanczos
representation of the phonon Green's function. Our calculations incorporate ab
initio dynamical matrices and electron-phonon couplings from the density
functional theory code ABINIT. Illustrative results are presented for several
elemental metals and for Einstein and Debye models with a range of coupling
constants. These are compared with experiment and other theoretical models.
Estimates of corrections to Migdal's theorem are obtained by comparing with
leading order contributions to the self-energy, and are found to be significant
only for large electron-phonon couplings at low temperatures
A Measurement of the Cosmic Microwave Background Damping Tail from the 2500-Square-Degree SPT-SZ Survey
We present a measurement of the cosmic microwave background (CMB) temperature power spectrum using data from the recently completed South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey. This measurement is made from observations of 2540 deg^2 of sky with arcminute resolution at 150 GHz, and improves upon previous measurements using the SPT by tripling the sky area. We report CMB temperature anisotropy power over the multipole range 650 < ℓ < 3000. We fit the SPT bandpowers, combined with the 7 yr Wilkinson Microwave Anisotropy Probe (WMAP7) data, with a six-parameter ΛCDM cosmological model and find that the two datasets are consistent and well fit by the model. Adding SPT measurements significantly improves ΛCDM parameter constraints; in particular, the constraint on θ_s tightens by a factor of 2.7. The impact of gravitational lensing is detected at 8.1σ, the most significant detection to date. This sensitivity of the SPT+WMAP7 data to lensing by large-scale structure at low redshifts allows us to constrain the mean curvature of the observable universe with CMB data alone to be Ω_k=-0.003^(+0.014)_(-0.018). Using the SPT+WMAP7 data, we measure the spectral index of scalar fluctuations to be n_s = 0.9623 ± 0.0097 in the ΛCDM model, a 3.9σ preference for a scale-dependent spectrum with n_s < 1. The SPT measurement of the CMB damping tail helps break the degeneracy that exists between the tensor-to-scalar ratio r and n_s in large-scale CMB measurements, leading to an upper limit of r < 0.18 (95% C.L.) in the ΛCDM+r model. Adding low-redshift measurements of the Hubble constant (H_0) and the baryon acoustic oscillation (BAO) feature to the SPT+WMAP7 data leads to further improvements. The combination of SPT+WMAP7+H_0+BAO constrains n_s = 0.9538 ± 0.0081 in the ΛCDM model, a 5.7σ detection of n_s < 1, and places an upper limit of r < 0.11 (95% C.L.) in the ΛCDM+r model. These new constraints on n_s and r have significant implications for our understanding of inflation, which we discuss in the context of selected single-field inflation models
Are Differences in Exposure to a Multicomponent School-Based Intervention Associated With Varying Dietary Outcomes in Adolescents?
Multicomponent interventions are recommended for health behavior change among adolescents. However, it is difficult to disentangle the effects of multiple intervention components. This article reports outcomes associated with varying levels of exposure to a school-based nutrition intervention, Teens Eating for Energy and Nutrition at School (TEENS). Four incremental exposureswere possible: (1) control group, (2) school environment interventions only, (3) classroom plus environment interventions, and (4) peer leaders plus classroom plus environment interventions. Patterns suggesting dose response were observed, with peer leaders reporting the largest increases in fruit, vegetable, and lower fat food consumption. Students exposed to classroom plus environment interventions also improved, whereas students exposed only to school environment interventions showed trends toward choosing lower fat foods and declining fruit intake and no change in vegetable intake. Control students’ choices remained stable. Future studies may investigate mechanisms for peer leaders’ changes, maximizing curriculum effectiveness, and improving environmental interventions
Texas applications system verification and transfer remote sensing information subsystem: Functional design
There are no author-identified significant results in this report
Principles behind evaluations of national food and beverage taxes and other regulatory efforts
Non-PRIFPRI3; ISIPHN
Changes in Plasma Creatinine Concentration after Cardiac Anesthesia with Isoflurane, Propofol, or Sevoflurane A Randomized Clinical Trial
Background: Renal impairment often follows cardiac surgery. The authors investigated whether sevoflurane produces greater increases in plasma creatinine concentration than isoflurane or propofol after elective coronary artery surgery. Methods: As part of maintenance anesthesia, including during cardiopulmonary bypass, patients were randomly allocated to receive one of three agents: isoflurane (n ؍ 118), sevoflurane (n ؍ 118), or propofol (n ؍ 118). Results: The differences between the groups were small, clinically unimportant, and not statistically significant for the primary analysis and subgroups. The proportions of patients with creatinine increases greater than 44 M were 15% in the isoflurane group, 17% in the sevoflurane group, and 11% in the propofol group (P ؍ 0.45). The median increases were 8 M in the isoflurane group, 4 M in the sevoflurane group, and 6 M in the propofol group. The differences between the three median maximum increases were 1-4 M (P > 0.45). In the subgroup with preoperative renal impairment, the median increases were 10 M in the isoflurane group, 15 M in the sevoflurane group, and 5 M in the propofol group (P ؍ 0.72). Conclusions: Sevoflurane did not produce greater increases in creatinine than isoflurane or propofol after elective coronary artery surgery
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