17,006 research outputs found
The B-ring's surface mass density from hidden density waves: Less than meets the eye?
Saturn's B ring is the most opaque ring in our solar system, but many of its
fundamental parameters, including its total mass, are not well constrained.
Spiral density waves generated by mean-motion resonances with Saturn's moons
provide some of the best constraints on the rings' mass density, but detecting
and quantifying such waves in the B ring has been challenging because of this
ring's high opacity and abundant fine-scale structure. Using a wavelet-based
analyses of 17 occultations of the star gamma Crucis observed by the Visual and
Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft, we are
able to examine five density waves in the B ring. Two of these waves are
generated by the Janus 2:1 and Mimas 5:2 Inner Lindblad Resonances at 96,427 km
and 101,311 km from Saturn's center, respectively. Both of these waves can be
detected in individual occultation profiles, but the multi-profile wavelet
analysis reveals unexpected variations in the pattern speed of the Janus 2:1
wave that might arise from the periodic changes in Janus' orbit. The other
three wave signatures are associated with the Janus 3:2, Enceladus 3:1 and
Pandora 3:2 Inner Lindblad Resonances at 115,959 km, 115,207 km and 108,546 km.
These waves are not visible in individual profiles, but structures with the
correct pattern speeds can be detected in appropriately phase-corrected average
wavelets. Estimates of the ring's surface mass density derived from these five
waves fall between 40 and 140 g/cm^2, even though the ring's optical depth in
these regions ranges from 1.5 to almost 5. This suggests that the total mass of
the B ring is most likely between one-third and two-thirds the mass of Saturn's
moon Mimas.Comment: 40 Pages, 21 Figures, Accepted for publication in Icarus, a few typos
fixe
Shaping the future for primary care education and training project. Integrated health and social care: the perspectives of people using services: a mixed methods analysis
The aim of this study was to explore service users' perspectives concerning integrated health & social care, and
to identify the perceived strengths and weaknesses associated with the current workforce and services provided. The findings will be used to inform the education and training of
the health and social care workforce in the North West of Englan
Validation of the performance of the Aquantic 2100A fish counter
This report looks at the validation of the performance of the Logie 2100A fish counter which was carried out at Forge Weir (River Lune) and Gunnislake Fish Pass (River Tamar), using a video recording system
IMPACTS OF THE NORTHEAST INTERSTATE DAIRY COMPACT ON NEW ENGLAND MILK SUPPLY
A two-equation random coefficients model and two estimates of milk prices in the absence of the Northeast Interstate Dairy Compact (Compact) are used to estimate the impact of minimum price regulation for fluid milk products on milk production in the New England states. Estimated responses to price enhancement differed by state for cow numbers, but parameters for milk per cow were not significantly different among states. The amount of increase in milk production attributed to the Compact is estimated at 45 million pounds (about 1% of production) during the first year of minimum price regulation, primarily due to increased milk per cow.Demand and Price Analysis,
Play-based pedagogy under threat? A small-scale study of teachers’ and pupils’ perceptions of pedagogical discontinuity in the transition to primary school
This study explored teachers’ and pupils’ perceptions of pedagogical discontinuity in the transition from Reception to Year 1. Data were collected through interviews with one Early Years Foundation Stage (EYFS) and one Year 1 teacher in the same setting. A questionnaire distributed to Year 1 children (n = 23) provided supplementary data. Findings revealed that teachers and pupils were aware of pedagogical discontinuity in the transition from EYFS to Year 1. Teachers attributed pedagogical discontinuity to the constraints of the National Curriculum. Pressures to ensure children are ‘school ready’ also have implications for bridging pedagogical discontinuity through play
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