192 research outputs found
The edge-on spiral gravitational lens B1600+434
We present new observations of the gravitational lens (GL) system B1600+434,
strongly suggesting that the lens is an edge-on spiral galaxy. These
observations are used to constrain the mass model of the system, in particular
the oblateness and velocity dispersion of the dark matter halo around the
lensing galaxy. From an analytical model we find a lower limit on the halo
oblateness q_\rmn{halo}=(c/a)_{\rho}\ga0.4; more detailed numerical models
give a lower limit q_\rmn{h}\ga0.5. We determine an average halo velocity
dispersion of km/s over all non-singular isothermal
elliptical (NIE) halo models. Constraining the models to larger and more
massive disks, decreases this average by only 10 km/s. A lower limit of
\sigma_{halo}\ga 150 km/s is found, even for disk masses larger then the mass
inside the Einstein radius. This lower limit indicates the need for a massive
dark matter halo, contributing at least half of the mass inside the Einstein
radius. Time delay calculations give days for the NIE halo
model and days for the modified Hubble profile (MHP) halo
model. Although the time delay for both NIE and MHP halo models is well
constrained on our parameter grid, it strongly depends on the halo surface
density profile. We furthermore find that the presence of a flat luminous mass
distribution can severely alter the statistical properties of the lens.Comment: 35 pages including 10 PS-figures, and 4 tables. Accepted for
publication by MNRA
Validation of epidermal AMBRA1 and loricrin (AMBLor) as a prognostic biomarker for nonulcerated American Joint Committee on Cancer stage I/II cutaneous melanoma
\ua9 2023 The Author(s). Published by Oxford University Press on behalf of British Association of Dermatologists.Background: Combined expression of the autophagy-regulatory protein AMBRA1 (activating molecule in Beclin1-regulated autophagy) and the terminal differentiation marker loricrin in the peritumoral epidermis of stage I melanomas can identify tumour subsets at low risk of -metastasis. Objectives: To validate the combined expression of peritumoral AMBRA1 and loricrin (AMBLor) as a prognostic biomarker able to identify both stage I and II melanomas at low risk of tumour recurrence. Methods: Automated immunohistochemistry was used to analyse peritumoral AMBRA1 and loricrin expression in geographically distinct discovery (n = 540) and validation (n = 300) cohorts of nonulcerated American Joint Committee on Cancer (AJCC) stage I and II melanomas. AMBLor status was correlated with clinical outcomes in the discovery and validation cohorts separately and combined. Results: Analysis of AMBLor in the discovery cohort revealed a recurrence-free survival (RFS) rate of 95.5% in the AMBLor low-risk group vs. 81.7% in the AMBLor at-risk group (multivariate log-rank, P < 0.001) and a negative predictive value (NPV) of 96.0%. In the validation cohort, AMBLor analysis revealed a RFS rate of 97.6% in the AMBLor low-risk group vs. 78.3% in the at-risk group (multivariate log-rank, P < 0.001) and a NPV of 97.6%. In a multivariate model considering AMBLor, Breslow thickness, age and sex, analysis of the combined discovery and validation cohorts showed that the estimated effect of AMBLor was statistically significant, with a hazard ratio of 3.469 (95% confidence interval 1.403-8.580, P = 0.007) and an overall NPV of 96.5%. Conclusions: These data provide further evidence validating AMBLor as a prognostic biomarker to identify nonulcerated AJCC stage I and II melanoma tumours at low risk of disease recurrence
More than just a bracelet: the use of material symbolism to communicate love
There is growing recognition of the place of love in residential care for children (Smith, 2009). This paper is a critical analysis of a range of existing research on residential child care as well as studies of material culture and of care relationships more broadly. It argues that, despite increasing regulation and surveillance, adults and children find ways to show and feel love in the context of residential care. Whilst love may be regarded as something to be avoided or indeed prohibited in an adult/child care setting these deep bonds find expression in the everyday life of the children's home. By looking at love in this embodied way, the 'realness' of material things to assert connection and recognition of love (Layne, 2000) is examined. As Gorenstein (1996, p.8) suggests 'objects...[are] the perfect vehicles for conveying themes that are not commonly accepted in a community'. The paper emphasises the recognition of these symbolic and metaphorical forms of communication in practice
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