Effectiveness of nurse home-visiting for disadvantaged families: results of a natural experiment

Extent: 9p.Objective: To evaluate the effects of a postnatal home-visiting programme delivered by community health nurses to socially disadvantaged mothers in South Australia. Design: The intervention group of 428 mothers lived in metropolitan Adelaide and the comparison group of 239 mothers lived in regional towns where the programme was not yet available. All participating mothers met health service eligibility criteria for enrolment in the home-visiting programme. Participants in both groups were assessed at baseline (mean child age=14.4 weeks SD=2.3), prior to programme enrolment, and again when the children were aged 9, 18 and 24 months. Setting: State-wide community child health service. Participants: 667 socially disadvantaged mothers enrolled consecutively. 487 mothers (73%) completed the 24-month assessment. Intervention: Two-year postnatal home-visiting programme based on the Family Partnership Model. Primary outcome measures: Parent Stress Index (PSI), Kessler Psychological Distress Scale and the Ages and Stages Questionnaire. Results: Mixed models adjusting for baseline differences were used to compare outcomes in the two groups. The mothers in the home-visiting group reported greater improvement on the PSI subscales assessing a mother's perceptions on the quality of their relationship with their child (1.10, 95% CI 0.06 to 2.14) and satisfaction with their role as parents (0.46, 95% CI −0.15 to 1.07) than mothers in the comparison group. With the exception of childhood sleeping problems, there were no other significant differences in the outcomes across the two groups. Conclusions: The findings suggest that home-visiting programmes delivered by community health nurses as part of routine clinical practice have the potential to improve maternal–child relationships and help mothers adjust to their role as parents.Michael Gifford Sawyer, Linda Frost, Kerrie Bowering, John Lync

SRB ascent aerodynamic heating design criteria reduction study, volume 1

An independent set of solid rocket booster (SRB) convective ascent design environments were produced which would serve as a check on the Rockwell IVBC-3 environments used to design the ascent phase of flight. In addition, support was provided for lowering the design environments such that Thermal Protection System (TPS), based on conservative estimates, could be removed leading to a reduction in SRB refurbishment time and cost. Ascent convective heating rates and loads were generated at locations in the SRB where lowering the thermal environment would impact the TPS design. The ascent thermal environments are documented along with the wind tunnel/flight test data base used as well as the trajectory and environment generation methodology. Methodology, as well as, environment summaries compared to the 1980 Design and Rockwell IVBC-3 Design Environment are presented in this volume, 1

Temporal and spectral characteristics of solar flare hard X-ray emission

Solar Maximum Mission observations of three flares that impose stringent constraints on physical models of the hard X-ray production during the impulsive phase are presented. Hard X-ray imaging observations of the flares on 1980 November 5 at 22:33 UT show two patches in the 16 to 30 keV images that are separated by 70,000 km and that brighten simultaneously to within 5 s. Observations to O V from one of the footprints show simultaneity of the brightening in this transition zone line and in the total hard X-ray flux to within a second or two. These results suggest but do not require the existence of electron beams in this flare. The rapid fluctuations of the hard X-ray flux within some flares on the time scales of 1 s also provide evidence for electron beams and limits on the time scale of the energy release mechanism. Observations of a flare on 1980 June 6 at 22:34 UT show variations in the 28 keV X-ray counting rate from one 20 ms interval to the next over a period of 10 s. The hard X-ray spectral variations measured with 128 ms time resolution for one 0.5 s spike during this flare are consistent with the predictions of thick-target non-thermal beam model

High resolution astronomical imaging through the turbulent atmosphere

technical reportThis research is principally concerned with the digital reconstruction of star images observed with large ground-based telescopes, although the techniques developed here will have application to a broad class of reconstruction problems. Since the work of Labeyrie, the difficulty in producing accurate and detailed reconstructions of stars has stemmed primarily from the extreme degradation of the phase spectrum caused by the atmospheric turbulence, and secondarily from the low-pass filter characteristic of the telescope itself. In this research, we describe solutions to both problems. Our phase estimator is based on the Knox-Thompson phase difference estimator, which we have extended and modified to produce more accurate estimates. The performance of this estimator is evaluated by simulation at various signal-to-noise ratios. We also describe a new non-linear super-resolution algorithm which appears to exhibit the best accuracy and convergence characteristics of any such algorithm proposed to date. It is also evaluated empirically. These two techniques were then used to restore images of the stars Betelgeuse and Capella. In the latter restoration resolution is realized well beyond the diffraction-limit of the telescope. Both reconstructions are consistent with known astrophysical facts, and both appear to be of high quality

From Instantons to Sphalerons: Time-Dependent Periodic Solutions of SU(2)-Higgs Theory

We solve numerically for periodic, spherically symmetric, classical solutions of SU(2)-Higgs theory in four-dimensional Euclidean space. In the limit of short periods the solutions approach tiny instanton-anti-instanton superpositions while, for longer periods, the solutions merge with the static sphaleron. A previously predicted bifurcation point, where two branches of periodic solutions meet, appears for Higgs boson masses larger than $3.091 M_W$.Comment: 14 pages, RevTeX with eps figure

High energy X-ray spectra of cygnus XR-1 observed from OSO-8

X-ray spectra of Cygnus XR-1 were measured with the scintillation spectrometer on board the OSO-8 satellite during a period of one and one-half to three weeks in each of the years from 1975 to 1977. Observations were made when the source was both in a high state and in a low state. Typical spectra of the source between 15 and 250 keV are presented. The observed pivoting effect is consistent with two temperature accretion disk models of the X-ray emitting region. No significant break in the spectrum occurred at energies up to 150 keV. The high state as defined in the 3 to 6 keV bandwidth was found to be the higher luminosity state of the X-ray source. One transition from a low to a high state occurred during observations. The time of occurrence of this and other transitions is consistent with the hypothesis that all intensity transitions occur near periastron of the binary system, and that such transitions are caused by changes in the mass transfer rate between the primary and the accretion disk around the secondary

Large-angle Electron-photon Coincidence Experiment In Atomic Hydrogen

1s-2p excitation in hydrogen has been studied by observing the angular correlation of Lyman photons detected in coincidence with inelastically scattered electrons at 54.4 eV incident energy. The electron scattering angles ranged from 10°to 133°; the results at scattering angles larger than 20°cannot be explained by currently available theories. © 1980 The American Physical Society

Information extraction and transmission techniques for spaceborne synthetic aperture radar images

Information extraction and transmission techniques for synthetic aperture radar (SAR) imagery were investigated. Four interrelated problems were addressed. An optimal tonal SAR image classification algorithm was developed and evaluated. A data compression technique was developed for SAR imagery which is simple and provides a 5:1 compression with acceptable image quality. An optimal textural edge detector was developed. Several SAR image enhancement algorithms have been proposed. The effectiveness of each algorithm was compared quantitatively

X-ray observations of AM Herculis from OSO-8

The white dwarf binary system AM Herculis (2A1815+500) was observed in X-rays at both low energies (E less 10 keV) and higher energies. The exact shape of the spectrum, particularly at the higher energies, has yet to be determined. Results from the high energy scintillation spectrometer on OSO-8 are presented. These are combined with results published elsewhere obtained concurrently with the proportional counter on the same satellite, thereby giving for the first time coincident observations of AM Her over the range 2 to 250 keV