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Participatory action research in the development and delivery of self-harm awareness sessions in prison: involving service users in staff development
Vertical occupational mobility and its measurement
This paper describes a number of alternative approaches to devising a vertical occupational scale and compares the outcomes of different scales on calculations of occupational mobility. The paper describes the conceptual issues relevant to calculating occupational mobility and documents the measurement error embedded in the choice of measure, as applied to different data sets. The ranking schemes used include SOC (9) major codes ranked by mean occupational hourly earnings, Hope-Goldthorpe collapsed 36-point scores, a 15-category SOC ranking based on educational qualifications, and a 77 category ranking based on 2-digit SOC90 occupations, wage rates, educational qualifications, training and job tenure. These ranking schemes are applied to data from the 1958 NCDS cohort between the ages of 23 to 33 and 33 to 42, and to 1.25 year transitions in the Quarterly Labour Force Survey panel data. The calculations carried out show that variations in the extent of vertical occupational mobility, both upward and downward, had systematic elements. The extent of mobility was found to vary by the composition of the individuals´ data particularly in terms of lifecourse stages and gender, the number of categories in the ranking scheme, attrition in the data and flows out of employment over the mobility period, and changes in labour market conditions over time. However, the sizes of these effects were very variable
Locally linear embedding: dimension reduction of massive protostellar spectra
We present the results of the application of locally linear embedding (LLE)
to reduce the dimensionality of dereddened and continuum subtracted
near-infrared spectra using a combination of models and real spectra of massive
protostars selected from the Red MSX Source survey database. A brief comparison
is also made with two other dimension reduction techniques; Principal Component
Analysis (PCA) and Isomap using the same set of spectra as well as a more
advanced form of LLE, Hessian locally linear embedding. We find that whilst LLE
certainly has its limitations, it significantly outperforms both PCA and Isomap
in classification of spectra based on the presence/absence of emission lines
and provides a valuable tool for classification and analysis of large spectral
data sets.Comment: 8 pages, 7 figures. Accepted for publication in MNRAS 2016 June 2
-SDYM fields and heavenly spaces: II. Reductions of the -SDYM system
Reductions of self-dual Yang-Mills (SDYM) system for -bracket Lie
algebra to the Husain-Park (HP) heavenly equation and to
sl(N,{\boldmath{C}) SDYM equation are given. An example of a sequence of
chiral fields () tending for to a curved heavenly
space is found.Comment: 18 page
From 2D Integrable Systems to Self-Dual Gravity
We explain how to construct solutions to the self-dual Einstein vacuum
equations from solutions of various two-dimensional integrable systems by
exploiting the fact that the Lax formulations of both systems can be embedded
in that of the self-dual Yang--Mills equations. We illustrate this by
constructing explicit self-dual vacuum metrics on , where
is a homogeneous space for a real subgroup of SL(2, \C) associated
with the two-dimensional system.Comment: 9 pages, LaTex, no figure
A review and meta analysis of health state utility values in breast cancer
Background and purpose:
Health-related quality of life is an important issue in the treatment of breast cancer, and health-state utilities are essential for cost-utility analysis. This paper identifies and summarises published utilities for common health-related quality of life outcomes for breast cancer, considers the impact of variation in study designs used, and pools utilities for some breast cancer health states.
Data sources and study selection:
13 databases were searched using key words relating to breast cancer and utility measurement. Articles were included if specified empirical methods for deriving utility values were used and details of the method, including number of respondents, were given. Articles were excluded if values were based on expert opinion or were not unique.
Data extraction and synthesis:
The authors identified 49 articles which met their inclusion criteria, providing 476 unique utilities for breast cancer health states. Where possible, mean utility estimates were pooled using ordinary least squares with utilities clustered within study group and weighted by both number of respondents and inverse of the variance of each utility. Regressions included controls for disease state, utility assessment method and other features of study design.
Results:
Utility values found in the review are summarised for six categories: 1) screening related states, 2) preventative states, 3) adverse events in breast cancer and its treatment, 4) non-specific breast cancer, 5) metastatic breast cancer states and 6) early breast cancer states. Pooled utility values for the latter two categories are estimated, showing base state utility values of between 0.668 and 0.782 for early breast cancer and 0.721 and 0.806 metastatic breast cancer depending upon which model is used. Utilities were found to vary significantly by valuation method, and who conducted the valuation.
Conclusions:
A large number of utility values for breast cancer are available in the literature; the states that these refer to are often complex, making pooling of values problematic
On the horseshoe drag of a low-mass planet. I - Migration in isothermal disks
We investigate the unsaturated horseshoe drag exerted on a low-mass planet by
an isothermal gaseous disk. In the globally isothermal case, we use a formal-
ism, based on the use of a Bernoulli invariant, that takes into account
pressure effects, and that extends the torque estimate to a region wider than
the horse- shoe region. We find a result that is strictly identical to the
standard horseshoe drag. This shows that the horseshoe drag accounts for the
torque of the whole corotation region, and not only of the horseshoe region,
thereby deserving to be called corotation torque. We find that evanescent waves
launched downstream of the horseshoe U-turns by the perturbations of vortensity
exert a feed-back on the upstream region, that render the horseshoe region
asymmetric. This asymmetry scales with the vortensity gradient and with the
disk's aspect ratio. It does not depend on the planetary mass, and it does not
have any impact on the horseshoe drag. Since the horseshoe drag has a steep
dependence on the width of the horseshoe region, we provide an adequate
definition of the width that needs to be used in horseshoe drag estimates. We
then consider the case of locally isothermal disks, in which the tempera- ture
is constant in time but depends on the distance to the star. The horseshoe drag
appears to be different from the case of a globally isothermal disk. The
difference, which is due to the driving of vortensity in the vicinity of the
planet, is intimately linked to the topology of the flow. We provide a
descriptive inter- pretation of these effects, as well as a crude estimate of
the dependency of the excess on the temperature gradient.Comment: Accepted for publication in Ap
Dual-spin attitude control for outer planet missions
The applicability of dual-spin technology to a Jupiter orbiter with probe mission was investigated. Basic mission and system level attitude control requirements were established and preliminary mechanization and control concepts developed. A comprehensive 18-degree-of-freedom digital simulation was utilized extensively to establish control laws, study dynamic interactions, and determined key sensitivities. Fundamental system/subsystem constraints were identified, and the applicability of dual-spin technology to a Jupiter orbiter with probe mission was validated
Near-IR Spectropolarimetry of NGC 1088
Original paper can be found at: http://www.astrosociety.org/pubs/cs/035-069.html--Copyright Astronomical Society of the PacificThe current unified model of Seyfert galaxies, as proposed by Antonucci and Miller (1985), has most, if not all, Seyfert 2 galaxies hosting a Seyfert 1 type nucleus in their cores. The broad lines from the type 1 nucleus can be scattered and be seen in the polarized flux spectrum, provided the geometry is correct. Whether the mechanism is electron or dust scattering has been a question of some debate. Since dust would normally have a low scattering efficiency in the infrared, near-IR spectropolarimetry should help in determing the nature of the scatterers. To this end we present the first near-IR spectropolarimetry of NGC 1068 a "Seyfert 2" galaxy in which polarized broad lines have been observed at optical wavelengths
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