35 research outputs found
A New Spin on Galactic Dust
We present a new puzzle involving Galactic microwave emission and attempt to
resolve it. On one hand, a cross-correlation analysis of the WHAM H-alpha map
with the Tenerife 10 and 15 GHz maps shows that the well-known DIRBE correlated
microwave emission cannot be dominated by free-free emission. On the other
hand, recent high resolution observations in the 8-10 GHz range with the Green
Bank 140 ft telescope by Finkbeiner et al. failed to find the corresponding 8
sigma signal that would be expected in the simplest spinning dust models. So
what physical mechanism is causing this ubiquitous dust-correlated emission? We
argue for a model predicting that spinning dust is the culprit after all, but
that the corresponding small grains are well correlated with the larger grains
seen at 100 micron only on large angular scales. In support of this grain
segregation model, we find the best spinning dust template to involve higher
frequency maps in the range 12-60 micron, where emission from transiently
heated small grains is important. Upcoming CMB experiments such as ground-based
interferometers, MAP and Planck LFI with high resolution at low frequencies
should allow a definitive test of this model.Comment: Minor revisions to match accepted ApJ version. 6 pages, 4 figs. Color
figures and more foreground information at
http://www.hep.upenn.edu/~angelica/foreground.html#spin or from
[email protected]
Shall I tell my mentor? Exploring the mentor-student relationship and its impact on students’ raising concerns on clinical placement
Aims
To explore student nurses' and nurse mentors' perceptions and experiences of raising concerns on clinical placement and the influence (if any) of their relationship on this process. A secondary aim is to consider the above, from a regulatory perspective in light of current literature and policy developments.
Background
Raising concerns whilst on clinical placement has been shown to be challenging for student nurses internationally. Registered nurses in the UK (in this case called “nurse mentors”) facilitate learning and assessment in practice. However, limited research exists on the influence of the relationship between the nurse mentor and student nurse on the raising concerns process.
Design
A qualitative approach was used to undertake secondary thematic analysis of interview data. The primary data set was generated during a PhD study, focusing on the mentor–student dynamic and the possible influence of this relationship on students' raising concerns.
Methods
30 individual semi‐structured interviews were subjected to concurrent and thematic analysis. Interviews were undertaken with student nurses (n = 16) and nurse mentors (n = 14) between April 2016–January 2018. The COREQ 32‐item checklist was used during the preparation of this article.
Findings
The following three interrelated analytical themes were generated from the data, “developing a mentor‐student relationship," “keeping your mentor sweet” and “the mentor role in the raising concerns process.”
Conclusion
Our analysis of participants' experiences and perceptions offers an original contribution to understanding the factors associated with student nurses raising concerns in practice. Student nurses and most mentors believed that students should be encouraged and supported to raise concerns, but students' decisions were strongly influenced by their perceptions of the immediate interpersonal and educational context. Similar barriers to raising concerns have been shown to exist regardless of geographical boundaries, therefore the findings of this study are nationally and internationally relevant
Significant benefits of AIP testing and clinical screening in familial isolated and young-onset pituitary tumors
Context
Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are responsible for a subset of familial isolated pituitary adenoma (FIPA) cases and sporadic pituitary neuroendocrine tumors (PitNETs).
Objective
To compare prospectively diagnosed AIP mutation-positive (AIPmut) PitNET patients with clinically presenting patients and to compare the clinical characteristics of AIPmut and AIPneg PitNET patients.
Design
12-year prospective, observational study.
Participants & Setting
We studied probands and family members of FIPA kindreds and sporadic patients with disease onset ≤18 years or macroadenomas with onset ≤30 years (n = 1477). This was a collaborative study conducted at referral centers for pituitary diseases.
Interventions & Outcome
AIP testing and clinical screening for pituitary disease. Comparison of characteristics of prospectively diagnosed (n = 22) vs clinically presenting AIPmut PitNET patients (n = 145), and AIPmut (n = 167) vs AIPneg PitNET patients (n = 1310).
Results
Prospectively diagnosed AIPmut PitNET patients had smaller lesions with less suprasellar extension or cavernous sinus invasion and required fewer treatments with fewer operations and no radiotherapy compared with clinically presenting cases; there were fewer cases with active disease and hypopituitarism at last follow-up. When comparing AIPmut and AIPneg cases, AIPmut patients were more often males, younger, more often had GH excess, pituitary apoplexy, suprasellar extension, and more patients required multimodal therapy, including radiotherapy. AIPmut patients (n = 136) with GH excess were taller than AIPneg counterparts (n = 650).
Conclusions
Prospectively diagnosed AIPmut patients show better outcomes than clinically presenting cases, demonstrating the benefits of genetic and clinical screening. AIP-related pituitary disease has a wide spectrum ranging from aggressively growing lesions to stable or indolent disease course
Shaping the growth behaviour of biofilms initiated from bacterial aggregates
Bacterial biofilms are usually assumed to originate from individual cells
deposited on a surface. However, many biofilm-forming bacteria tend to
aggregate in the planktonic phase so that it is possible that many natural and
infectious biofilms originate wholly or partially from pre-formed cell
aggregates. Here, we use agent-based computer simulations to investigate the
role of pre-formed aggregates in biofilm development. Focusing on the initial
shape the aggregate forms on the surface, we find that the degree of spreading
of an aggregate on a surface can play an important role in determining its
eventual fate during biofilm development. Specifically, initially spread
aggregates perform better when competition with surrounding unaggregated
bacterial cells is low, while initially rounded aggregates perform better when
competition with surrounding unaggregated cells is high. These contrasting
outcomes are governed by a trade-off between aggregate surface area and height.
Our results provide new insight into biofilm formation and development, and
reveal new factors that may be at play in the social evolution of biofilm
communities
The Evolution of British Monetarism, 1968 - 1979
How far were monetary targets imposed on the post-1974 Labour Government by international and domestic financial markets enthused with the doctrines of ‘monetarism’? The following paper attempts to answer this question by demonstrating the complex and contingent nature of the ascent of British ‘monetarism’ after 1968. It describes the post-devaluation valorisation of the ‘money supply’ which led investors to realign their expectations with the behaviour of the monetary aggregates. The collapse of the global fixed-exchange rate regime, coupled with vast domestic inflationary pressures after 1973, determined that investors came to employ the ‘money supply’ as a convenient new measure with which to assess the ‘soundness’ of British economic management. The critical juncture of the 1976 Sterling crisis forced the Labour Government into a reluctant adoption of monetary targets as part of a desperate attempt to regain market confidence. The result was to impose significant constraints on the Government’s economic policymaking freedom, as attempts were made to retain favourable money supply figures exposed to the short-term volatility of increasingly-globalised and highly-capitalized financial market