12,617 research outputs found
NASA-JSC antenna near-field measurement system
Work was completed on the near-field range control software. The capabilities of the data processing software were expanded with the addition of probe compensation. In addition, the user can process the measured data from the same computer terminal used for range control. The design of the laser metrology system was completed. It provides precise measruement of probe location during near-field measurements as well as position data for control of the translation beam and probe cart. A near-field range measurement system was designed, fabricated, and tested
Reduced healthcare utilisation following successful HCV treatment in HIV co-infected patients with mild liver disease
New direct-acting antivirals (DAA) for hepatitis C virus (HCV) infection have achieved high cure rates in many patient groups previously considered difficult-to-treat, including those HIV/HCV co-infected. The high price of these medications is likely to limit access to treatment, at least in the short term. Early treatment priority is likely to be given to those with advanced disease, but a more detailed understanding of the potential benefits in treating those with mild disease is needed. We hypothesized that successful HCV treatment within a co-infected population with mild liver disease would lead to a reduction in the use and costs of healthcare services in the 5 years following treatment completion. We performed a retrospective cohort study of HIV/HCV-co-infected patients without evidence of fibrosis/cirrhosis who received a course of HCV therapy between 2004 and 2013. Detailed analysis of healthcare utilization up to 5 years following treatment for each patient using clinical and electronic records was used to estimate healthcare costs. Sixty-three patients were investigated, of whom 48 of 63 (76.2%) achieved sustained virological response 12 weeks following completion of therapy (SVR12). Individuals achieving SVR12 incurred lower health utilization costs (£5000 per-patient) compared to (£10 775 per-patient) non-SVR patients in the 5 years after treatment. Healthcare utilization rates and costs in the immediate 5 years following treatment were significantly higher in co-infected patients with mild disease that failed to achieve SVR12. These data suggest additional value to achieving cure beyond the prevention of complications of disease
Kinetic Damage from Meteorites
Ballistic (kinetic energy) damage from falling meteorites has been recorded in two cases: the 1954 Sylacuga, Alabama meteorite of 4 kilogram mass which indirectly hit Ann Hodges and the 1992 Mbale meteorite fall where a 4 gram-sized meteorite struck a young boy. Neither event was fatal. Structures damaged by meteorites are much more common and include mail boxes (Figure 1) and cars (Figure2). Figure 3 shows that meteorite fragments of order 0.1 kilograms may cause serious human injury/fatality. Halliday et al (1985) estimated a human is struck once per decade by a meteorite (most likely gram-sized) while more than a dozen structures should be impacted annually by meteorite fragments
Electrostatic protection of the Solar Power Satellite and rectenna
Several features of the interactions of the solar power satellite (SPS) with its space environment were examined theoretically. The voltages produced at various surfaces due to space plasmas and the plasma leakage currents through the kapton and sapphire solar cell blankets were calculated. At geosynchronous orbit, this parasitic power loss is only 0.7%, and is easily compensated by oversizing. At low-Earth orbit, the power loss is potentially much larger (3%), and anomalous arcing is expected for the EOTV high voltage negative surfaces. Preliminary results of a three dimensional self-consistent plasma and electric field computer program are presented, confirming the validity of the predictions made from the one dimensional models. Magnetic shielding of the satellite, to reduce the power drain and to protect the solar cells from energetic electron and plasma ion bombardment is considered. It is concluded that minor modifications can allow the SPS to operate safely and efficiently in its space environment. The SPS design employed in this study is the 1978 MSFC baseline design utilizing GaAs solar cells at CR-2 and an aluminum structure
SU(3) breaking in hyperon transition vector form factors
We present a calculation of the SU(3)-breaking corrections to the hyperon
transition vector form factors to in heavy baryon chiral
perturbation theory with finite-range regularisation. Both octet and decuplet
degrees of freedom are included. We formulate a chiral expansion at the
kinematic point , which can be conveniently accessed
in lattice QCD. The two unknown low-energy constants at this point are
constrained by lattice QCD simulation results for the
and transition form factors. Hence we determine
lattice-informed values of at the physical point. This work constitutes
progress towards the precise determination of from hyperon
semileptonic decays
Palliation and life quality in lung cancer; how good are clinicians at judging treatment outcome?
A recent trial by the MRC Lung Cancer Working Party used physician assessments to compare two palliative schedules of radiotherapy in lung cancer. A prospective study has been undertaken on a subset of these trial patients to see how physician assessments of symptomatic relief and general condition correlate with patient perception of therapeutic response. In 40 patients followed up monthly from presentation until close to death, good agreement was found between doctors and patients on change in specific physical symptoms and overall physical condition. Doctors were poor judges of life quality at presentation but appeared able to identify relative improvement or deterioration in overall quality of life. In conclusion, physician assessments may constitute valid end-points for radiotherapy trials comparing palliative schedules in lung cancer
Factors Influencing Largemouth Bass Recruitment: Implications for the Illinois Management and Stocking Program
Annual Progress Report issued August 2002; NOTE: Two different reports numbered 02/06
were issued from the CAE.Report issued on: August 2002INHS Technical Report prepared for Division of Fisheries Illinois Department of Natural
Resource
Stability of radiation-pressure dominated disks. I. The dispersion relation for a delayed heating alpha-viscosity prescription
We derive and investigate the dispersion relation for accretion disks with
retarded or advanced heating. We follow the alpha-prescription but allow for a
time offset (\tau) between heating and pressure perturbations, as well as for a
diminished response of heating to pressure variations. We study in detail
solutions of the dispersion relation for disks with radiation-pressure fraction
1 - \beta . For \tau <0 (delayed heating) the number and sign of real solutions
for the growth rate depend on the values of the time lag and the ratio of
heating response to pressure perturbations, \xi . If the delay is larger than a
critical value (e.g., if \Omega \tau <-125 for \alpha =0.1, \beta =0 and \xi
=1) two real solutions exist, which are both negative. These results imply that
retarded heating may stabilize radiation-pressure dominated accretion disks.Comment: 11 pages, 10 figures, to be submitted to A&
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