Simple processors of star tracker commands for stabilizing an inertially oriented satellite

Simple processors of star tracker commands for stabilizing inertially oriented satellit

Aerothermal modeling program, phase 2

The main objectives of the Aerothermal Modeling Program, Phase 2 are: to develop an improved numerical scheme for incorporation in a 3-D combustor flow model; to conduct a benchmark quality experiment to study the interaction of a primary jet with a confined swirling crossflow and to assess current and advanced turbulence and scalar transport models; and to conduct experimental evaluation of the air swirler interaction with fuel injectors, assessments of current two-phase models, and verification the improved spray evaporation/dispersion models

Understanding single-top-quark production and jets at hadron colliders

I present an analysis of fully differential single-top-quark production plus jets at next-to-leading order. I describe the effects of jet definitions, top-quark mass, and higher orders on the shapes and normalizations of the kinematic distributions, and quantify all theoretical uncertainties. I explain how to interpret next-to-leading-order jet calculations, and compare them to showering event generators. Using the program ZTOP, I show that HERWIG and PYTHIA significantly underestimate both s-channel and t-channel single-top-quark production, and propose a scheme to match the relevant samples to the next-to-leading-order predictions.Comment: 40 pgs., revtex4, 35 ps figs; added Fig. 4, 1 Ref., minor clarifications, to appear in Phys. Rev.

Water Quality Evaluation Yatesville Lake Project: Volume 1

Point sources of pollution identified in the Blaine Creek watershed area consisted of oil and gas facility sources and mine related sources. A total of 493 point sources of pollution were inventoried which included 167 oil and gas related sources, 321 mine sediment structures, and 5 hollow fill groundwater seeps. The highest concentration of these point sources of pollution occurred in the south to southwest portion of the watershed in the area proximate to the Martha Field. Adverse impacts to surface and groundwaters resulting from the 326 mine and groundwater point sources of pollution identified did not appear significant as compared with oil and brine related impacts when referenced by specific conductance, total organic carbon, and ph

Ramsey interferometry with oppositely detuned fields

We report a narrowing of the interference pattern obtained in an atomic Ramsey interferometer if the two separated fields have different frequency and their phase difference is controlled. The width of the Ramsey fringes depends inversely on the free flight time of ground state atoms before entering the first field region in addition to the time between the fields. The effect is stable also for atomic wavepackets with initial position and momentum distributions and for realistic mode functions.Comment: 6 pages, 6 figure

Positron emission tomography PET/CT harmonisation study of different clinical PET/CT scanners using commercially available software

Objectives: Harmonisation is the process whereby standardised uptake values from different scanners can be made comparable. This PET/CT pilot study aimed to evaluate the effectiveness of harmonisation of a modern scanner with image reconstruction incorporating resolution recovery (RR) with another vendor older scanner operated in two-dimensional (2D) mode, and for both against a European standard (EARL). The vendor-proprietary software EQ•PET was used, which achieves harmonisation with a Gaussian smoothing. A substudy investigated effect of RR on harmonisation. Methods: Phantom studies on each scanner were performed to optimise the smoothing parameters required to achieve successful harmonisation. 80 patients were retrospectively selected; half were imaged on each scanner. As proof of principle, a cohort of 10 patients was selected from the modern scanner subjects to study the effects of RR on harmonisation. Results: Before harmonisation, the modern scanner without RR adhered to EARL specification. Using the phantom data, filters were derived for optimal harmonisation between scanners and with and without RR as applicable, to the EARL standard. The 80-patient cohort did not reveal any statistically significant differences. In the 10-patient cohort SUVmax for RR > no RR irrespective of harmonisation but differences lacked statistical significance (one-way ANOVA F(3.36) = 0.37, p = 0.78). Bland-Altman analysis showed that harmonisation reduced the SUVmax ratio between RR and no RR to 1.07 (95% CI 0.96–1.18) with no outliers. Conclusions: EQ•PET successfully enabled harmonisation between modern and older scanners and against the EARL standard. Harmonisation reduces SUVmax and dependence on the use of RR in the modern scanner. Advances in knowledge: EQ•PET is feasible to harmonise different PET/CT scanners and reduces the effect of RR on SUVmax

Corrigendum "Portal protein diversity and phage ecology"

Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Environmental Microbiology 13 (2011): 2832, doi:10.1111/j.1462-2920.2011.02616.x