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Zoning patterns of Fe and V in spinel from a type B Ca-Al-rich inclusion: Constraints on subsolidus thermal history
We obtained two-dimensional concentration maps for the minor elements Fe and V in 21 spinel crystals in the Allende type B1 inclusion TS-34 with a 4â5 ÎŒm resolution. Locally high concentrations of Fe occur along at least one edge of the spinels and decrease toward the center of the grains. Enrichment in V can also occur along edges or at corners. In general, there is no overall correlation of the Fe and V distributions, but in local regions of two grains, the V and Fe distributions are correlated, strongly suggesting a local source for both elements. In these two grains, opaque assemblages are present that appear to locally control the V distributions. This, coupled with previous work, suggests that prior to alteration, TS-34 contained V-rich metal. Oxidation of this metal during alteration can account for the edge/corner V enrichments, but provide only minor FeO contributions, explaining the overall lack of correlation between Fe and V. Most of the FeO appears to have been externally introduced along spinel boundaries during alteration. These alteration phases served as sources for diffusion of FeO into spinel. FeO distributions in spinel lead to a mean attenuation length of ~8 ÎŒm and, using literature diffusion coefficients in isothermal and exponential cooling approximations for peak temperatures in the range 600â700°C, this leads to a time scale for calcium-aluminum-rich inclusion (CAI) alteration in the range of decades to centuries
Materials Older Than Ca-Al-Rich Inclusions
Concentrations of refractory lithophile elements (RLEs) in Type B1 Ca-Al-rich inclusions (CAIs) are dominated by submicron inclusions, which are potentially relict grains older than the host CAI. These objects are so common, albeit tiny, that it is often very difficult to find a âpureâ melilite
Confidentiality and public protection: ethical dilemmas in qualitative research with adult male sex offenders
This paper considers the ethical tensions present when engaging in in-depth interviews with convicted sex offenders. Many of the issues described below are similar to those found in other sensitive areas of research. However, confidentiality and public protection are matters that require detailed consideration when the desire to know more about men who have committed serious and harmful offences is set against the possibility of a researcher not disclosing previously unknown sensitive information that relates to the risk of someone being harmed.</p
Which patients are assessed by lung cancer nurse specialists? A national lung cancer audit study of over 128,000 patients across England
Background: Lung cancer nurse specialists (LCNS) are integral to the multidisciplinary clinical team, providing personalised physical and psycho-social interventions, and care management for people with lung cancer. The National Institute of Health and Care Excellence (NICE) recommend that all patients have access to a LCNS. We conducted a national study assessing whether there is variation in access to and timing of LCNS assessment.
Methods: The National Cancer Action Teamâs LCNS workforce census in England was linked with patient and hospital Trust data from the English National Lung Cancer Audit. Multivariate logistic regression was used to assess features associated with LCNS assessment.
Results: 128,124 lung cancer patients were seen from 2007 to 2011. LCNS assessment confirmation was âyesâ in 62%, ânoâ in 6% and âmissingâ in 32%. Where (in clinic versus ward) and when (before versus after diagnosis) patients were assessed by a LCNS also varied. Older patients with poor performance status, early cancer stage, and comorbidities were less likely to be assessed; there was no difference with sex or socioeconomic group. Patients receiving any anti-cancer treatment were more likely to be assessed. Assessment was lower in Trusts with high annual patient numbers (odds ratio = 0.58, 95% confidence interval 0.37â0.91) and where LCNS caseload > 250 (0.69, 0.41â1.16, although not statistically significant), but increased where workload was conducted mostly by band 8 nurses (2.22, 1.22â4.02).
Conclusion: LCNS assessment varied by patient and Trust features, which may indicate unmet need for some patients. The current workforce needs to expand as well as retain experienced LCNSs
The Las Campanas IR Survey: Early Type Galaxy Progenitors Beyond Redshift One
(Abridged) We have identified a population of faint red galaxies from a 0.62
square degree region of the Las Campanas Infrared Survey whose properties are
consistent with their being the progenitors of early-type galaxies. The optical
and IR colors, number-magnitude relation and angular clustering together
indicate modest evolution and increased star formation rates among the
early-type field population at redshifts between one and two. The counts of red
galaxies with magnitudes between 17 and 20 rise with a slope that is much
steeper than that of the total H sample. The surface density of red galaxies
drops from roughly 3000 per square degree at H = 20.5, I-H > 3 to ~ 20 per
square degree at H = 20, I-H > 5. The V-I colors are approximately 1.5
magnitudes bluer on average than a pure old population and span a range of more
than three magnitudes. The colors, and photometric redshifts derived from them,
indicate that the red galaxies have redshift distributions adequately described
by Gaussians with sigma_z ~ 0.2V-I3$ are primarily in the 1.5 < z < 2
range. We find co-moving correlation lengths of 9-10 Mpc at z ~ 1, comparable
to, or larger than, those found for early-type galaxies at lower redshifts. A
simple photometric evolution model reproduces the counts of the red galaxies,
with only a ~ 30% decline in the underlying space density of early-type
galaxies at z ~ 1.2. We suggest on the basis of the colors, counts, and
clustering that these red galaxies are the bulk of the progenitors of present
day early-type galaxies.Comment: 5 pages, 3 figures, accepted for publication in the ApJ Letter
Feasibility of Iodine and Bromine Analysis in Genesis Solar Wind Collectors
Comparison of elemental abundances in sun, meteorites and earth
provides understanding of the formation and evolution of the solar
system. Yet, the majority of the solar system abundances are based on
meteoritic values [1â6]. Here we report an attempt to estimate a feasibility
of direct measurements of iodine and bromine in the GENESIS solar
wind Aluminum on Sapphire collector (AloS) using neutron induced
conversions: ^(127)I(n,ÎłÎČ)^(128)Xe, ^(79)Br(n,ÎłÎČ)^(80)Kr and ^(81)Br(n,ÎłÎČ)^(82)Kr
Do working practices of cancer nurse specialists improve clinical outcomes? Retrospective cohort analysis from the English National Lung Cancer Audit
Background
Cancer nurse specialists are advanced practitioners who offer continuity of care and expert support for people diagnosed with specific cancers. Health Education England's Cancer Workforce Plan prioritises expansion of cancer nurse specialist numbers by 2021 as part of the Cancer Taskforce Strategy for England.
Objective
To assess whether working practices of advanced practice specialist nurses are associated with clinical outcomes for people with lung cancer.
Methods
Adults with non-small cell lung cancer followed from 30 days post-diagnosis in English secondary care were obtained from the English National Lung Cancer Audit, 2007 to 2011. A national survey of lung cancer nurse specialists provided information on self-reported working practices. Mortality and unplanned admissions from 30 days to 12 months post diagnosis were respectively analysed using Cox and Poisson regression. Outcomes were assessed according to patientsâ receipt of initial assessments by a lung cancer nurse specialist and according to trust-level reported working practices. Regression models were adjusted for individual sociodemographic and clinical characteristics, error adjusted for intracorrelations within regional cancer networks, and presented separately according to patientsâ treatment pathways (surgery, chemotherapy, radiotherapy, or no anti-cancer therapy).
Results
Data for 108,115 people with lung cancer were analysed and associations with mortality and unplanned admissions were infrequent. Among people receiving only radiotherapy, however, the hazard for death was 17% lower among those who received an assessment by a lung cancer nurse specialist, compared with no assessment (hazard ratio = 0.83, 95% confidence interval 0.73â0.94; p = 0.003). The hazard was also lower among those receiving surgery (hazard ratio = 0.91, 0.84â0.99; p = 0.028). Among those receiving radiotherapy, nurse specialistsâ reported confidence within multidisciplinary team settings was associated with a lower risk of death (hazard ratio = 0.88, 0.78â1.00; p = 0.049) and a lower rate of unplanned cancer-related admissions (incidence rate ratio = 0.83, 0.73â0.95; p = 0.007). Lung cancer nurse specialist assessments before/at diagnosis, were associated with a 5% lower rate of unplanned admissions, compared to when assessments occurred after diagnosis.
Conclusion
The contribution of nurse specialist working practices was occasionally associated with better outcomes for people with lung cancer. These were not limited to a single treatment pathway, but do indicate discrete relationships within pathways. Our study provides initial measures of overall lung cancer nurse specialist working practices at trusts, however, more detailed studies with longitudinal measurement of lung cancer nurse specialist-patient interaction are needed to better ascertain impacts on long-term patient outcomes. The findings highlight opportunities for potential improvement in effectiveness of service and care management
The Las Campanas Infrared Survey. III. The H-band Imaging Survey and the Near-Infrared and Optical Photometric Catalogs
(Abridged) The Las Campanas Infrared Survey, based on broad-band optical and
near-infrared photometry, is designed to robustly identify a statistically
significant and representative sample of evolved galaxies at redshifts z>1. We
have completed an H-band imaging survey over 1.1 square degrees of sky in six
separate fields. The average 5 sigma detection limit in a four arcsecond
diameter aperture is H ~ 20. Here we describe the design of the survey, the
observation strategies, data reduction techniques, and object identification
procedures. We present sample near-infrared and optical photometric catalogs
for objects identified in two survey fields. We perform object detection in all
bandpasses and identify ~ 54,000 galaxies over 1,408 square arcminutes of sky
in the two fields. Of these galaxies, ~ 14,000 are detected in the H-band and ~
2,000 have the colors of evolved galaxies, I - H >3, at z > 1. We find that (1)
the differential number counts N(m) for the H-band detected objects has a slope
of 0.44 at H 19. In addition, we find that (2) the
differential number counts for the H detected red objects has a slope of 0.85
at H 20, with a mean surface density ~ 3,000 degree^{-2}
mag^{-1} at H=20. Finally, we find that (3) galaxies with red optical to
near-IR colors (I-H > 3) constitute ~ 20% of the H detected galaxies at H ~ 21,
but only 2% at H = 19. We show that red galaxies are strongly clustered, which
results in a strong field to field variation in their surface density.
Comparisons of observations and predictions based on various formation
scenarios indicate that these red galaxies are consistent with mildly evolving
early-type galaxies at z ~ 1, although with a significant amount of on-going
star formation as indicated by the large scatter in their V-I colors.Comment: 48 pages, 13 figures, accepted for publication in the Astrophysical
Journa
Diagnosis by consensus: A case study in the importance of interdisciplinary interpretation of mummified remains.
Objective: The goal of this study is to demonstrate the need for interdisciplinary consensus and inclusion of mummy radiology specialists in analyses of mummified remains. Materials: This study uses paleoimaging data for an ancient Egyptian mummy at the Museum of Human Anatomy âFilippo Civininiâ. Methods: This study demonstrates the benefit of evaluation of mummified remains in a multi-disciplinary interpretive team. Results: The authors propose a diagnosis of DISH, additional signs of undifferentiated spondyloarthropathy, and lumbarisation of S1. Conclusions: The process of diagnosis by consensus is essential to the analysis of mummified remains, which are complexly altered through natural and anthropogenic processes in the millennia subsequent to the individualâs death. Significance: Mummy paleoimaging and paleopathology lacks a unifying set of standards. We present an example of the value to be found in the multi-disciplinary diagnosis by consensus approach. Limitations: We discuss numerous challenges to accurate and meaningful interpretation that radiography of mummified remains pose. Suggestions for Further Research: While the authors do not seek to impose any single set of standards, we do recommend a larger discussion on the topic of (culture-specific) standardisation in mummy paleoimaging and paleopathology. We further recommend the development of an international, multi-disciplinary panel of paleoimaging interpreters
Population history from the Neolithic to present on the Mediterranean island of Sardinia: an ancient DNA perspective
Recent ancient DNA studies of western Eurasia have revealed a dynamic history of admixture, with evidence for major migrations during the Neolithic and Bronze Age. The population of the Mediterranean island of Sardinia has been notable in these studies â} Neolithic individuals from mainland Europe cluster more closely with Sardinian individuals than with all other present-day Europeans. The current model to explain this result is that Sardinia received an initial influx of Neolithic ancestry and then remained relatively isolated from expansions in the later Neolithic and Bronze Age that took place in continental Europe. To test this model, we generated genome-wide capture data (approximately 1.2 million variants) for 43 ancient Sardinian individuals spanning the Neolithic through the Bronze Age, including individuals from Sardinia{â}s Nuragic culture, which is known for the construction of numerous large stone towers throughout the island. We analyze these new samples in the context of previously generated genome-wide ancient DNA data from 972 ancient individuals across western Eurasia and whole-genome sequence data from approximately 1,500 modern individuals from Sardinia. The ancient Sardinian individuals show a strong affinity to western Mediterranean Neolithic populations and we infer a high degree of genetic continuity on the island from the Neolithic (around fifth millennium BCE) through the Nuragic period (second millennium BCE). In particular, during the Bronze Age in Sardinia, we do not find significant levels of the {â}Steppe{â ancestry that was spreading in many other parts of Europe at that time. We also characterize subsequent genetic influx between the Nuragic period and the present. We detect novel, modest signals of admixture between 1,000 BCE and present-day, from ancestry sources in the eastern and northern Mediterranean. Within Sardinia, we confirm that populations from the more geographically isolated mountainous provinces have experienced elevated levels of genetic drift and that northern and southwestern regions of the island received more gene flow from outside Sardinia. Overall, our genetic analysis sheds new light on the origin of Neolithic settlement on Sardinia, reinforces models of genetic continuity on the island, and provides enhanced power to detect post-Bronze-Age gene flow. Together, these findings offer a refined demographic model for future medical genetic studies in Sardinia
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